Commit | Line | Data |
---|---|---|
bc0c38d1 SR |
1 | /* |
2 | * ring buffer based function tracer | |
3 | * | |
2b6080f2 | 4 | * Copyright (C) 2007-2012 Steven Rostedt <srostedt@redhat.com> |
bc0c38d1 SR |
5 | * Copyright (C) 2008 Ingo Molnar <mingo@redhat.com> |
6 | * | |
7 | * Originally taken from the RT patch by: | |
8 | * Arnaldo Carvalho de Melo <acme@redhat.com> | |
9 | * | |
10 | * Based on code from the latency_tracer, that is: | |
11 | * Copyright (C) 2004-2006 Ingo Molnar | |
6d49e352 | 12 | * Copyright (C) 2004 Nadia Yvette Chambers |
bc0c38d1 | 13 | */ |
2cadf913 | 14 | #include <linux/ring_buffer.h> |
273b281f | 15 | #include <generated/utsrelease.h> |
2cadf913 SR |
16 | #include <linux/stacktrace.h> |
17 | #include <linux/writeback.h> | |
bc0c38d1 SR |
18 | #include <linux/kallsyms.h> |
19 | #include <linux/seq_file.h> | |
3f5a54e3 | 20 | #include <linux/notifier.h> |
2cadf913 | 21 | #include <linux/irqflags.h> |
bc0c38d1 | 22 | #include <linux/debugfs.h> |
8434dc93 | 23 | #include <linux/tracefs.h> |
4c11d7ae | 24 | #include <linux/pagemap.h> |
bc0c38d1 SR |
25 | #include <linux/hardirq.h> |
26 | #include <linux/linkage.h> | |
27 | #include <linux/uaccess.h> | |
2cadf913 | 28 | #include <linux/kprobes.h> |
bc0c38d1 SR |
29 | #include <linux/ftrace.h> |
30 | #include <linux/module.h> | |
31 | #include <linux/percpu.h> | |
2cadf913 | 32 | #include <linux/splice.h> |
3f5a54e3 | 33 | #include <linux/kdebug.h> |
5f0c6c03 | 34 | #include <linux/string.h> |
f76180bc | 35 | #include <linux/mount.h> |
7e53bd42 | 36 | #include <linux/rwsem.h> |
5a0e3ad6 | 37 | #include <linux/slab.h> |
bc0c38d1 SR |
38 | #include <linux/ctype.h> |
39 | #include <linux/init.h> | |
2a2cc8f7 | 40 | #include <linux/poll.h> |
b892e5c8 | 41 | #include <linux/nmi.h> |
bc0c38d1 | 42 | #include <linux/fs.h> |
8bd75c77 | 43 | #include <linux/sched/rt.h> |
86387f7e | 44 | |
bc0c38d1 | 45 | #include "trace.h" |
f0868d1e | 46 | #include "trace_output.h" |
bc0c38d1 | 47 | |
73c5162a SR |
48 | /* |
49 | * On boot up, the ring buffer is set to the minimum size, so that | |
50 | * we do not waste memory on systems that are not using tracing. | |
51 | */ | |
55034cd6 | 52 | bool ring_buffer_expanded; |
73c5162a | 53 | |
8e1b82e0 FW |
54 | /* |
55 | * We need to change this state when a selftest is running. | |
ff32504f FW |
56 | * A selftest will lurk into the ring-buffer to count the |
57 | * entries inserted during the selftest although some concurrent | |
5e1607a0 | 58 | * insertions into the ring-buffer such as trace_printk could occurred |
ff32504f FW |
59 | * at the same time, giving false positive or negative results. |
60 | */ | |
8e1b82e0 | 61 | static bool __read_mostly tracing_selftest_running; |
ff32504f | 62 | |
b2821ae6 SR |
63 | /* |
64 | * If a tracer is running, we do not want to run SELFTEST. | |
65 | */ | |
020e5f85 | 66 | bool __read_mostly tracing_selftest_disabled; |
b2821ae6 | 67 | |
0daa2302 SRRH |
68 | /* Pipe tracepoints to printk */ |
69 | struct trace_iterator *tracepoint_print_iter; | |
70 | int tracepoint_printk; | |
71 | ||
adf9f195 FW |
72 | /* For tracers that don't implement custom flags */ |
73 | static struct tracer_opt dummy_tracer_opt[] = { | |
74 | { } | |
75 | }; | |
76 | ||
77 | static struct tracer_flags dummy_tracer_flags = { | |
78 | .val = 0, | |
79 | .opts = dummy_tracer_opt | |
80 | }; | |
81 | ||
8c1a49ae SRRH |
82 | static int |
83 | dummy_set_flag(struct trace_array *tr, u32 old_flags, u32 bit, int set) | |
adf9f195 FW |
84 | { |
85 | return 0; | |
86 | } | |
0f048701 | 87 | |
7ffbd48d SR |
88 | /* |
89 | * To prevent the comm cache from being overwritten when no | |
90 | * tracing is active, only save the comm when a trace event | |
91 | * occurred. | |
92 | */ | |
93 | static DEFINE_PER_CPU(bool, trace_cmdline_save); | |
94 | ||
0f048701 SR |
95 | /* |
96 | * Kill all tracing for good (never come back). | |
97 | * It is initialized to 1 but will turn to zero if the initialization | |
98 | * of the tracer is successful. But that is the only place that sets | |
99 | * this back to zero. | |
100 | */ | |
4fd27358 | 101 | static int tracing_disabled = 1; |
0f048701 | 102 | |
9288f99a | 103 | DEFINE_PER_CPU(int, ftrace_cpu_disabled); |
d769041f | 104 | |
955b61e5 | 105 | cpumask_var_t __read_mostly tracing_buffer_mask; |
ab46428c | 106 | |
944ac425 SR |
107 | /* |
108 | * ftrace_dump_on_oops - variable to dump ftrace buffer on oops | |
109 | * | |
110 | * If there is an oops (or kernel panic) and the ftrace_dump_on_oops | |
111 | * is set, then ftrace_dump is called. This will output the contents | |
112 | * of the ftrace buffers to the console. This is very useful for | |
113 | * capturing traces that lead to crashes and outputing it to a | |
114 | * serial console. | |
115 | * | |
116 | * It is default off, but you can enable it with either specifying | |
117 | * "ftrace_dump_on_oops" in the kernel command line, or setting | |
cecbca96 FW |
118 | * /proc/sys/kernel/ftrace_dump_on_oops |
119 | * Set 1 if you want to dump buffers of all CPUs | |
120 | * Set 2 if you want to dump the buffer of the CPU that triggered oops | |
944ac425 | 121 | */ |
cecbca96 FW |
122 | |
123 | enum ftrace_dump_mode ftrace_dump_on_oops; | |
944ac425 | 124 | |
de7edd31 SRRH |
125 | /* When set, tracing will stop when a WARN*() is hit */ |
126 | int __disable_trace_on_warning; | |
127 | ||
9828413d SRRH |
128 | #ifdef CONFIG_TRACE_ENUM_MAP_FILE |
129 | /* Map of enums to their values, for "enum_map" file */ | |
130 | struct trace_enum_map_head { | |
131 | struct module *mod; | |
132 | unsigned long length; | |
133 | }; | |
134 | ||
135 | union trace_enum_map_item; | |
136 | ||
137 | struct trace_enum_map_tail { | |
138 | /* | |
139 | * "end" is first and points to NULL as it must be different | |
140 | * than "mod" or "enum_string" | |
141 | */ | |
142 | union trace_enum_map_item *next; | |
143 | const char *end; /* points to NULL */ | |
144 | }; | |
145 | ||
146 | static DEFINE_MUTEX(trace_enum_mutex); | |
147 | ||
148 | /* | |
149 | * The trace_enum_maps are saved in an array with two extra elements, | |
150 | * one at the beginning, and one at the end. The beginning item contains | |
151 | * the count of the saved maps (head.length), and the module they | |
152 | * belong to if not built in (head.mod). The ending item contains a | |
153 | * pointer to the next array of saved enum_map items. | |
154 | */ | |
155 | union trace_enum_map_item { | |
156 | struct trace_enum_map map; | |
157 | struct trace_enum_map_head head; | |
158 | struct trace_enum_map_tail tail; | |
159 | }; | |
160 | ||
161 | static union trace_enum_map_item *trace_enum_maps; | |
162 | #endif /* CONFIG_TRACE_ENUM_MAP_FILE */ | |
163 | ||
607e2ea1 | 164 | static int tracing_set_tracer(struct trace_array *tr, const char *buf); |
b2821ae6 | 165 | |
ee6c2c1b LZ |
166 | #define MAX_TRACER_SIZE 100 |
167 | static char bootup_tracer_buf[MAX_TRACER_SIZE] __initdata; | |
b2821ae6 | 168 | static char *default_bootup_tracer; |
d9e54076 | 169 | |
55034cd6 SRRH |
170 | static bool allocate_snapshot; |
171 | ||
1beee96b | 172 | static int __init set_cmdline_ftrace(char *str) |
d9e54076 | 173 | { |
67012ab1 | 174 | strlcpy(bootup_tracer_buf, str, MAX_TRACER_SIZE); |
b2821ae6 | 175 | default_bootup_tracer = bootup_tracer_buf; |
73c5162a | 176 | /* We are using ftrace early, expand it */ |
55034cd6 | 177 | ring_buffer_expanded = true; |
d9e54076 PZ |
178 | return 1; |
179 | } | |
1beee96b | 180 | __setup("ftrace=", set_cmdline_ftrace); |
d9e54076 | 181 | |
944ac425 SR |
182 | static int __init set_ftrace_dump_on_oops(char *str) |
183 | { | |
cecbca96 FW |
184 | if (*str++ != '=' || !*str) { |
185 | ftrace_dump_on_oops = DUMP_ALL; | |
186 | return 1; | |
187 | } | |
188 | ||
189 | if (!strcmp("orig_cpu", str)) { | |
190 | ftrace_dump_on_oops = DUMP_ORIG; | |
191 | return 1; | |
192 | } | |
193 | ||
194 | return 0; | |
944ac425 SR |
195 | } |
196 | __setup("ftrace_dump_on_oops", set_ftrace_dump_on_oops); | |
60a11774 | 197 | |
de7edd31 SRRH |
198 | static int __init stop_trace_on_warning(char *str) |
199 | { | |
933ff9f2 LCG |
200 | if ((strcmp(str, "=0") != 0 && strcmp(str, "=off") != 0)) |
201 | __disable_trace_on_warning = 1; | |
de7edd31 SRRH |
202 | return 1; |
203 | } | |
933ff9f2 | 204 | __setup("traceoff_on_warning", stop_trace_on_warning); |
de7edd31 | 205 | |
3209cff4 | 206 | static int __init boot_alloc_snapshot(char *str) |
55034cd6 SRRH |
207 | { |
208 | allocate_snapshot = true; | |
209 | /* We also need the main ring buffer expanded */ | |
210 | ring_buffer_expanded = true; | |
211 | return 1; | |
212 | } | |
3209cff4 | 213 | __setup("alloc_snapshot", boot_alloc_snapshot); |
55034cd6 | 214 | |
7bcfaf54 SR |
215 | |
216 | static char trace_boot_options_buf[MAX_TRACER_SIZE] __initdata; | |
7bcfaf54 SR |
217 | |
218 | static int __init set_trace_boot_options(char *str) | |
219 | { | |
67012ab1 | 220 | strlcpy(trace_boot_options_buf, str, MAX_TRACER_SIZE); |
7bcfaf54 SR |
221 | return 0; |
222 | } | |
223 | __setup("trace_options=", set_trace_boot_options); | |
224 | ||
e1e232ca SR |
225 | static char trace_boot_clock_buf[MAX_TRACER_SIZE] __initdata; |
226 | static char *trace_boot_clock __initdata; | |
227 | ||
228 | static int __init set_trace_boot_clock(char *str) | |
229 | { | |
230 | strlcpy(trace_boot_clock_buf, str, MAX_TRACER_SIZE); | |
231 | trace_boot_clock = trace_boot_clock_buf; | |
232 | return 0; | |
233 | } | |
234 | __setup("trace_clock=", set_trace_boot_clock); | |
235 | ||
0daa2302 SRRH |
236 | static int __init set_tracepoint_printk(char *str) |
237 | { | |
238 | if ((strcmp(str, "=0") != 0 && strcmp(str, "=off") != 0)) | |
239 | tracepoint_printk = 1; | |
240 | return 1; | |
241 | } | |
242 | __setup("tp_printk", set_tracepoint_printk); | |
de7edd31 | 243 | |
cf8e3474 | 244 | unsigned long long ns2usecs(cycle_t nsec) |
bc0c38d1 SR |
245 | { |
246 | nsec += 500; | |
247 | do_div(nsec, 1000); | |
248 | return nsec; | |
249 | } | |
250 | ||
983f938a SRRH |
251 | /* trace_flags holds trace_options default values */ |
252 | #define TRACE_DEFAULT_FLAGS \ | |
253 | (FUNCTION_DEFAULT_FLAGS | \ | |
254 | TRACE_ITER_PRINT_PARENT | TRACE_ITER_PRINTK | \ | |
255 | TRACE_ITER_ANNOTATE | TRACE_ITER_CONTEXT_INFO | \ | |
256 | TRACE_ITER_RECORD_CMD | TRACE_ITER_OVERWRITE | \ | |
257 | TRACE_ITER_IRQ_INFO | TRACE_ITER_MARKERS) | |
258 | ||
16270145 SRRH |
259 | /* trace_options that are only supported by global_trace */ |
260 | #define TOP_LEVEL_TRACE_FLAGS (TRACE_ITER_PRINTK | \ | |
261 | TRACE_ITER_PRINTK_MSGONLY | TRACE_ITER_RECORD_CMD) | |
262 | ||
263 | ||
4fcdae83 SR |
264 | /* |
265 | * The global_trace is the descriptor that holds the tracing | |
266 | * buffers for the live tracing. For each CPU, it contains | |
267 | * a link list of pages that will store trace entries. The | |
268 | * page descriptor of the pages in the memory is used to hold | |
269 | * the link list by linking the lru item in the page descriptor | |
270 | * to each of the pages in the buffer per CPU. | |
271 | * | |
272 | * For each active CPU there is a data field that holds the | |
273 | * pages for the buffer for that CPU. Each CPU has the same number | |
274 | * of pages allocated for its buffer. | |
275 | */ | |
983f938a SRRH |
276 | static struct trace_array global_trace = { |
277 | .trace_flags = TRACE_DEFAULT_FLAGS, | |
278 | }; | |
bc0c38d1 | 279 | |
ae63b31e | 280 | LIST_HEAD(ftrace_trace_arrays); |
bc0c38d1 | 281 | |
ff451961 SRRH |
282 | int trace_array_get(struct trace_array *this_tr) |
283 | { | |
284 | struct trace_array *tr; | |
285 | int ret = -ENODEV; | |
286 | ||
287 | mutex_lock(&trace_types_lock); | |
288 | list_for_each_entry(tr, &ftrace_trace_arrays, list) { | |
289 | if (tr == this_tr) { | |
290 | tr->ref++; | |
291 | ret = 0; | |
292 | break; | |
293 | } | |
294 | } | |
295 | mutex_unlock(&trace_types_lock); | |
296 | ||
297 | return ret; | |
298 | } | |
299 | ||
300 | static void __trace_array_put(struct trace_array *this_tr) | |
301 | { | |
302 | WARN_ON(!this_tr->ref); | |
303 | this_tr->ref--; | |
304 | } | |
305 | ||
306 | void trace_array_put(struct trace_array *this_tr) | |
307 | { | |
308 | mutex_lock(&trace_types_lock); | |
309 | __trace_array_put(this_tr); | |
310 | mutex_unlock(&trace_types_lock); | |
311 | } | |
312 | ||
7f1d2f82 | 313 | int filter_check_discard(struct trace_event_file *file, void *rec, |
f306cc82 TZ |
314 | struct ring_buffer *buffer, |
315 | struct ring_buffer_event *event) | |
eb02ce01 | 316 | { |
5d6ad960 | 317 | if (unlikely(file->flags & EVENT_FILE_FL_FILTERED) && |
f306cc82 TZ |
318 | !filter_match_preds(file->filter, rec)) { |
319 | ring_buffer_discard_commit(buffer, event); | |
320 | return 1; | |
321 | } | |
322 | ||
323 | return 0; | |
324 | } | |
325 | EXPORT_SYMBOL_GPL(filter_check_discard); | |
326 | ||
2425bcb9 | 327 | int call_filter_check_discard(struct trace_event_call *call, void *rec, |
f306cc82 TZ |
328 | struct ring_buffer *buffer, |
329 | struct ring_buffer_event *event) | |
330 | { | |
331 | if (unlikely(call->flags & TRACE_EVENT_FL_FILTERED) && | |
332 | !filter_match_preds(call->filter, rec)) { | |
333 | ring_buffer_discard_commit(buffer, event); | |
334 | return 1; | |
335 | } | |
336 | ||
337 | return 0; | |
eb02ce01 | 338 | } |
f306cc82 | 339 | EXPORT_SYMBOL_GPL(call_filter_check_discard); |
eb02ce01 | 340 | |
ad1438a0 | 341 | static cycle_t buffer_ftrace_now(struct trace_buffer *buf, int cpu) |
37886f6a SR |
342 | { |
343 | u64 ts; | |
344 | ||
345 | /* Early boot up does not have a buffer yet */ | |
9457158b | 346 | if (!buf->buffer) |
37886f6a SR |
347 | return trace_clock_local(); |
348 | ||
9457158b AL |
349 | ts = ring_buffer_time_stamp(buf->buffer, cpu); |
350 | ring_buffer_normalize_time_stamp(buf->buffer, cpu, &ts); | |
37886f6a SR |
351 | |
352 | return ts; | |
353 | } | |
bc0c38d1 | 354 | |
9457158b AL |
355 | cycle_t ftrace_now(int cpu) |
356 | { | |
357 | return buffer_ftrace_now(&global_trace.trace_buffer, cpu); | |
358 | } | |
359 | ||
10246fa3 SRRH |
360 | /** |
361 | * tracing_is_enabled - Show if global_trace has been disabled | |
362 | * | |
363 | * Shows if the global trace has been enabled or not. It uses the | |
364 | * mirror flag "buffer_disabled" to be used in fast paths such as for | |
365 | * the irqsoff tracer. But it may be inaccurate due to races. If you | |
366 | * need to know the accurate state, use tracing_is_on() which is a little | |
367 | * slower, but accurate. | |
368 | */ | |
9036990d SR |
369 | int tracing_is_enabled(void) |
370 | { | |
10246fa3 SRRH |
371 | /* |
372 | * For quick access (irqsoff uses this in fast path), just | |
373 | * return the mirror variable of the state of the ring buffer. | |
374 | * It's a little racy, but we don't really care. | |
375 | */ | |
376 | smp_rmb(); | |
377 | return !global_trace.buffer_disabled; | |
9036990d SR |
378 | } |
379 | ||
4fcdae83 | 380 | /* |
3928a8a2 SR |
381 | * trace_buf_size is the size in bytes that is allocated |
382 | * for a buffer. Note, the number of bytes is always rounded | |
383 | * to page size. | |
3f5a54e3 SR |
384 | * |
385 | * This number is purposely set to a low number of 16384. | |
386 | * If the dump on oops happens, it will be much appreciated | |
387 | * to not have to wait for all that output. Anyway this can be | |
388 | * boot time and run time configurable. | |
4fcdae83 | 389 | */ |
3928a8a2 | 390 | #define TRACE_BUF_SIZE_DEFAULT 1441792UL /* 16384 * 88 (sizeof(entry)) */ |
3f5a54e3 | 391 | |
3928a8a2 | 392 | static unsigned long trace_buf_size = TRACE_BUF_SIZE_DEFAULT; |
bc0c38d1 | 393 | |
4fcdae83 | 394 | /* trace_types holds a link list of available tracers. */ |
bc0c38d1 | 395 | static struct tracer *trace_types __read_mostly; |
4fcdae83 | 396 | |
4fcdae83 SR |
397 | /* |
398 | * trace_types_lock is used to protect the trace_types list. | |
4fcdae83 | 399 | */ |
a8227415 | 400 | DEFINE_MUTEX(trace_types_lock); |
4fcdae83 | 401 | |
7e53bd42 LJ |
402 | /* |
403 | * serialize the access of the ring buffer | |
404 | * | |
405 | * ring buffer serializes readers, but it is low level protection. | |
406 | * The validity of the events (which returns by ring_buffer_peek() ..etc) | |
407 | * are not protected by ring buffer. | |
408 | * | |
409 | * The content of events may become garbage if we allow other process consumes | |
410 | * these events concurrently: | |
411 | * A) the page of the consumed events may become a normal page | |
412 | * (not reader page) in ring buffer, and this page will be rewrited | |
413 | * by events producer. | |
414 | * B) The page of the consumed events may become a page for splice_read, | |
415 | * and this page will be returned to system. | |
416 | * | |
417 | * These primitives allow multi process access to different cpu ring buffer | |
418 | * concurrently. | |
419 | * | |
420 | * These primitives don't distinguish read-only and read-consume access. | |
421 | * Multi read-only access are also serialized. | |
422 | */ | |
423 | ||
424 | #ifdef CONFIG_SMP | |
425 | static DECLARE_RWSEM(all_cpu_access_lock); | |
426 | static DEFINE_PER_CPU(struct mutex, cpu_access_lock); | |
427 | ||
428 | static inline void trace_access_lock(int cpu) | |
429 | { | |
ae3b5093 | 430 | if (cpu == RING_BUFFER_ALL_CPUS) { |
7e53bd42 LJ |
431 | /* gain it for accessing the whole ring buffer. */ |
432 | down_write(&all_cpu_access_lock); | |
433 | } else { | |
434 | /* gain it for accessing a cpu ring buffer. */ | |
435 | ||
ae3b5093 | 436 | /* Firstly block other trace_access_lock(RING_BUFFER_ALL_CPUS). */ |
7e53bd42 LJ |
437 | down_read(&all_cpu_access_lock); |
438 | ||
439 | /* Secondly block other access to this @cpu ring buffer. */ | |
440 | mutex_lock(&per_cpu(cpu_access_lock, cpu)); | |
441 | } | |
442 | } | |
443 | ||
444 | static inline void trace_access_unlock(int cpu) | |
445 | { | |
ae3b5093 | 446 | if (cpu == RING_BUFFER_ALL_CPUS) { |
7e53bd42 LJ |
447 | up_write(&all_cpu_access_lock); |
448 | } else { | |
449 | mutex_unlock(&per_cpu(cpu_access_lock, cpu)); | |
450 | up_read(&all_cpu_access_lock); | |
451 | } | |
452 | } | |
453 | ||
454 | static inline void trace_access_lock_init(void) | |
455 | { | |
456 | int cpu; | |
457 | ||
458 | for_each_possible_cpu(cpu) | |
459 | mutex_init(&per_cpu(cpu_access_lock, cpu)); | |
460 | } | |
461 | ||
462 | #else | |
463 | ||
464 | static DEFINE_MUTEX(access_lock); | |
465 | ||
466 | static inline void trace_access_lock(int cpu) | |
467 | { | |
468 | (void)cpu; | |
469 | mutex_lock(&access_lock); | |
470 | } | |
471 | ||
472 | static inline void trace_access_unlock(int cpu) | |
473 | { | |
474 | (void)cpu; | |
475 | mutex_unlock(&access_lock); | |
476 | } | |
477 | ||
478 | static inline void trace_access_lock_init(void) | |
479 | { | |
480 | } | |
481 | ||
482 | #endif | |
483 | ||
d78a4614 SRRH |
484 | #ifdef CONFIG_STACKTRACE |
485 | static void __ftrace_trace_stack(struct ring_buffer *buffer, | |
486 | unsigned long flags, | |
487 | int skip, int pc, struct pt_regs *regs); | |
2d34f489 SRRH |
488 | static inline void ftrace_trace_stack(struct trace_array *tr, |
489 | struct ring_buffer *buffer, | |
73dddbb5 SRRH |
490 | unsigned long flags, |
491 | int skip, int pc, struct pt_regs *regs); | |
ca475e83 | 492 | |
d78a4614 SRRH |
493 | #else |
494 | static inline void __ftrace_trace_stack(struct ring_buffer *buffer, | |
495 | unsigned long flags, | |
496 | int skip, int pc, struct pt_regs *regs) | |
497 | { | |
498 | } | |
2d34f489 SRRH |
499 | static inline void ftrace_trace_stack(struct trace_array *tr, |
500 | struct ring_buffer *buffer, | |
73dddbb5 SRRH |
501 | unsigned long flags, |
502 | int skip, int pc, struct pt_regs *regs) | |
ca475e83 SRRH |
503 | { |
504 | } | |
505 | ||
d78a4614 SRRH |
506 | #endif |
507 | ||
5280bcef | 508 | static void tracer_tracing_on(struct trace_array *tr) |
10246fa3 SRRH |
509 | { |
510 | if (tr->trace_buffer.buffer) | |
511 | ring_buffer_record_on(tr->trace_buffer.buffer); | |
512 | /* | |
513 | * This flag is looked at when buffers haven't been allocated | |
514 | * yet, or by some tracers (like irqsoff), that just want to | |
515 | * know if the ring buffer has been disabled, but it can handle | |
516 | * races of where it gets disabled but we still do a record. | |
517 | * As the check is in the fast path of the tracers, it is more | |
518 | * important to be fast than accurate. | |
519 | */ | |
520 | tr->buffer_disabled = 0; | |
521 | /* Make the flag seen by readers */ | |
522 | smp_wmb(); | |
523 | } | |
524 | ||
499e5470 SR |
525 | /** |
526 | * tracing_on - enable tracing buffers | |
527 | * | |
528 | * This function enables tracing buffers that may have been | |
529 | * disabled with tracing_off. | |
530 | */ | |
531 | void tracing_on(void) | |
532 | { | |
10246fa3 | 533 | tracer_tracing_on(&global_trace); |
499e5470 SR |
534 | } |
535 | EXPORT_SYMBOL_GPL(tracing_on); | |
536 | ||
09ae7234 SRRH |
537 | /** |
538 | * __trace_puts - write a constant string into the trace buffer. | |
539 | * @ip: The address of the caller | |
540 | * @str: The constant string to write | |
541 | * @size: The size of the string. | |
542 | */ | |
543 | int __trace_puts(unsigned long ip, const char *str, int size) | |
544 | { | |
545 | struct ring_buffer_event *event; | |
546 | struct ring_buffer *buffer; | |
547 | struct print_entry *entry; | |
548 | unsigned long irq_flags; | |
549 | int alloc; | |
8abfb872 J |
550 | int pc; |
551 | ||
983f938a | 552 | if (!(global_trace.trace_flags & TRACE_ITER_PRINTK)) |
f0160a5a J |
553 | return 0; |
554 | ||
8abfb872 | 555 | pc = preempt_count(); |
09ae7234 | 556 | |
3132e107 SRRH |
557 | if (unlikely(tracing_selftest_running || tracing_disabled)) |
558 | return 0; | |
559 | ||
09ae7234 SRRH |
560 | alloc = sizeof(*entry) + size + 2; /* possible \n added */ |
561 | ||
562 | local_save_flags(irq_flags); | |
563 | buffer = global_trace.trace_buffer.buffer; | |
564 | event = trace_buffer_lock_reserve(buffer, TRACE_PRINT, alloc, | |
8abfb872 | 565 | irq_flags, pc); |
09ae7234 SRRH |
566 | if (!event) |
567 | return 0; | |
568 | ||
569 | entry = ring_buffer_event_data(event); | |
570 | entry->ip = ip; | |
571 | ||
572 | memcpy(&entry->buf, str, size); | |
573 | ||
574 | /* Add a newline if necessary */ | |
575 | if (entry->buf[size - 1] != '\n') { | |
576 | entry->buf[size] = '\n'; | |
577 | entry->buf[size + 1] = '\0'; | |
578 | } else | |
579 | entry->buf[size] = '\0'; | |
580 | ||
581 | __buffer_unlock_commit(buffer, event); | |
2d34f489 | 582 | ftrace_trace_stack(&global_trace, buffer, irq_flags, 4, pc, NULL); |
09ae7234 SRRH |
583 | |
584 | return size; | |
585 | } | |
586 | EXPORT_SYMBOL_GPL(__trace_puts); | |
587 | ||
588 | /** | |
589 | * __trace_bputs - write the pointer to a constant string into trace buffer | |
590 | * @ip: The address of the caller | |
591 | * @str: The constant string to write to the buffer to | |
592 | */ | |
593 | int __trace_bputs(unsigned long ip, const char *str) | |
594 | { | |
595 | struct ring_buffer_event *event; | |
596 | struct ring_buffer *buffer; | |
597 | struct bputs_entry *entry; | |
598 | unsigned long irq_flags; | |
599 | int size = sizeof(struct bputs_entry); | |
8abfb872 J |
600 | int pc; |
601 | ||
983f938a | 602 | if (!(global_trace.trace_flags & TRACE_ITER_PRINTK)) |
f0160a5a J |
603 | return 0; |
604 | ||
8abfb872 | 605 | pc = preempt_count(); |
09ae7234 | 606 | |
3132e107 SRRH |
607 | if (unlikely(tracing_selftest_running || tracing_disabled)) |
608 | return 0; | |
609 | ||
09ae7234 SRRH |
610 | local_save_flags(irq_flags); |
611 | buffer = global_trace.trace_buffer.buffer; | |
612 | event = trace_buffer_lock_reserve(buffer, TRACE_BPUTS, size, | |
8abfb872 | 613 | irq_flags, pc); |
09ae7234 SRRH |
614 | if (!event) |
615 | return 0; | |
616 | ||
617 | entry = ring_buffer_event_data(event); | |
618 | entry->ip = ip; | |
619 | entry->str = str; | |
620 | ||
621 | __buffer_unlock_commit(buffer, event); | |
2d34f489 | 622 | ftrace_trace_stack(&global_trace, buffer, irq_flags, 4, pc, NULL); |
09ae7234 SRRH |
623 | |
624 | return 1; | |
625 | } | |
626 | EXPORT_SYMBOL_GPL(__trace_bputs); | |
627 | ||
ad909e21 SRRH |
628 | #ifdef CONFIG_TRACER_SNAPSHOT |
629 | /** | |
630 | * trace_snapshot - take a snapshot of the current buffer. | |
631 | * | |
632 | * This causes a swap between the snapshot buffer and the current live | |
633 | * tracing buffer. You can use this to take snapshots of the live | |
634 | * trace when some condition is triggered, but continue to trace. | |
635 | * | |
636 | * Note, make sure to allocate the snapshot with either | |
637 | * a tracing_snapshot_alloc(), or by doing it manually | |
638 | * with: echo 1 > /sys/kernel/debug/tracing/snapshot | |
639 | * | |
640 | * If the snapshot buffer is not allocated, it will stop tracing. | |
641 | * Basically making a permanent snapshot. | |
642 | */ | |
643 | void tracing_snapshot(void) | |
644 | { | |
645 | struct trace_array *tr = &global_trace; | |
646 | struct tracer *tracer = tr->current_trace; | |
647 | unsigned long flags; | |
648 | ||
1b22e382 SRRH |
649 | if (in_nmi()) { |
650 | internal_trace_puts("*** SNAPSHOT CALLED FROM NMI CONTEXT ***\n"); | |
651 | internal_trace_puts("*** snapshot is being ignored ***\n"); | |
652 | return; | |
653 | } | |
654 | ||
ad909e21 | 655 | if (!tr->allocated_snapshot) { |
ca268da6 SRRH |
656 | internal_trace_puts("*** SNAPSHOT NOT ALLOCATED ***\n"); |
657 | internal_trace_puts("*** stopping trace here! ***\n"); | |
ad909e21 SRRH |
658 | tracing_off(); |
659 | return; | |
660 | } | |
661 | ||
662 | /* Note, snapshot can not be used when the tracer uses it */ | |
663 | if (tracer->use_max_tr) { | |
ca268da6 SRRH |
664 | internal_trace_puts("*** LATENCY TRACER ACTIVE ***\n"); |
665 | internal_trace_puts("*** Can not use snapshot (sorry) ***\n"); | |
ad909e21 SRRH |
666 | return; |
667 | } | |
668 | ||
669 | local_irq_save(flags); | |
670 | update_max_tr(tr, current, smp_processor_id()); | |
671 | local_irq_restore(flags); | |
672 | } | |
1b22e382 | 673 | EXPORT_SYMBOL_GPL(tracing_snapshot); |
ad909e21 SRRH |
674 | |
675 | static int resize_buffer_duplicate_size(struct trace_buffer *trace_buf, | |
676 | struct trace_buffer *size_buf, int cpu_id); | |
3209cff4 SRRH |
677 | static void set_buffer_entries(struct trace_buffer *buf, unsigned long val); |
678 | ||
679 | static int alloc_snapshot(struct trace_array *tr) | |
680 | { | |
681 | int ret; | |
682 | ||
683 | if (!tr->allocated_snapshot) { | |
684 | ||
685 | /* allocate spare buffer */ | |
686 | ret = resize_buffer_duplicate_size(&tr->max_buffer, | |
687 | &tr->trace_buffer, RING_BUFFER_ALL_CPUS); | |
688 | if (ret < 0) | |
689 | return ret; | |
690 | ||
691 | tr->allocated_snapshot = true; | |
692 | } | |
693 | ||
694 | return 0; | |
695 | } | |
696 | ||
ad1438a0 | 697 | static void free_snapshot(struct trace_array *tr) |
3209cff4 SRRH |
698 | { |
699 | /* | |
700 | * We don't free the ring buffer. instead, resize it because | |
701 | * The max_tr ring buffer has some state (e.g. ring->clock) and | |
702 | * we want preserve it. | |
703 | */ | |
704 | ring_buffer_resize(tr->max_buffer.buffer, 1, RING_BUFFER_ALL_CPUS); | |
705 | set_buffer_entries(&tr->max_buffer, 1); | |
706 | tracing_reset_online_cpus(&tr->max_buffer); | |
707 | tr->allocated_snapshot = false; | |
708 | } | |
ad909e21 | 709 | |
93e31ffb TZ |
710 | /** |
711 | * tracing_alloc_snapshot - allocate snapshot buffer. | |
712 | * | |
713 | * This only allocates the snapshot buffer if it isn't already | |
714 | * allocated - it doesn't also take a snapshot. | |
715 | * | |
716 | * This is meant to be used in cases where the snapshot buffer needs | |
717 | * to be set up for events that can't sleep but need to be able to | |
718 | * trigger a snapshot. | |
719 | */ | |
720 | int tracing_alloc_snapshot(void) | |
721 | { | |
722 | struct trace_array *tr = &global_trace; | |
723 | int ret; | |
724 | ||
725 | ret = alloc_snapshot(tr); | |
726 | WARN_ON(ret < 0); | |
727 | ||
728 | return ret; | |
729 | } | |
730 | EXPORT_SYMBOL_GPL(tracing_alloc_snapshot); | |
731 | ||
ad909e21 SRRH |
732 | /** |
733 | * trace_snapshot_alloc - allocate and take a snapshot of the current buffer. | |
734 | * | |
735 | * This is similar to trace_snapshot(), but it will allocate the | |
736 | * snapshot buffer if it isn't already allocated. Use this only | |
737 | * where it is safe to sleep, as the allocation may sleep. | |
738 | * | |
739 | * This causes a swap between the snapshot buffer and the current live | |
740 | * tracing buffer. You can use this to take snapshots of the live | |
741 | * trace when some condition is triggered, but continue to trace. | |
742 | */ | |
743 | void tracing_snapshot_alloc(void) | |
744 | { | |
ad909e21 SRRH |
745 | int ret; |
746 | ||
93e31ffb TZ |
747 | ret = tracing_alloc_snapshot(); |
748 | if (ret < 0) | |
3209cff4 | 749 | return; |
ad909e21 SRRH |
750 | |
751 | tracing_snapshot(); | |
752 | } | |
1b22e382 | 753 | EXPORT_SYMBOL_GPL(tracing_snapshot_alloc); |
ad909e21 SRRH |
754 | #else |
755 | void tracing_snapshot(void) | |
756 | { | |
757 | WARN_ONCE(1, "Snapshot feature not enabled, but internal snapshot used"); | |
758 | } | |
1b22e382 | 759 | EXPORT_SYMBOL_GPL(tracing_snapshot); |
93e31ffb TZ |
760 | int tracing_alloc_snapshot(void) |
761 | { | |
762 | WARN_ONCE(1, "Snapshot feature not enabled, but snapshot allocation used"); | |
763 | return -ENODEV; | |
764 | } | |
765 | EXPORT_SYMBOL_GPL(tracing_alloc_snapshot); | |
ad909e21 SRRH |
766 | void tracing_snapshot_alloc(void) |
767 | { | |
768 | /* Give warning */ | |
769 | tracing_snapshot(); | |
770 | } | |
1b22e382 | 771 | EXPORT_SYMBOL_GPL(tracing_snapshot_alloc); |
ad909e21 SRRH |
772 | #endif /* CONFIG_TRACER_SNAPSHOT */ |
773 | ||
5280bcef | 774 | static void tracer_tracing_off(struct trace_array *tr) |
10246fa3 SRRH |
775 | { |
776 | if (tr->trace_buffer.buffer) | |
777 | ring_buffer_record_off(tr->trace_buffer.buffer); | |
778 | /* | |
779 | * This flag is looked at when buffers haven't been allocated | |
780 | * yet, or by some tracers (like irqsoff), that just want to | |
781 | * know if the ring buffer has been disabled, but it can handle | |
782 | * races of where it gets disabled but we still do a record. | |
783 | * As the check is in the fast path of the tracers, it is more | |
784 | * important to be fast than accurate. | |
785 | */ | |
786 | tr->buffer_disabled = 1; | |
787 | /* Make the flag seen by readers */ | |
788 | smp_wmb(); | |
789 | } | |
790 | ||
499e5470 SR |
791 | /** |
792 | * tracing_off - turn off tracing buffers | |
793 | * | |
794 | * This function stops the tracing buffers from recording data. | |
795 | * It does not disable any overhead the tracers themselves may | |
796 | * be causing. This function simply causes all recording to | |
797 | * the ring buffers to fail. | |
798 | */ | |
799 | void tracing_off(void) | |
800 | { | |
10246fa3 | 801 | tracer_tracing_off(&global_trace); |
499e5470 SR |
802 | } |
803 | EXPORT_SYMBOL_GPL(tracing_off); | |
804 | ||
de7edd31 SRRH |
805 | void disable_trace_on_warning(void) |
806 | { | |
807 | if (__disable_trace_on_warning) | |
808 | tracing_off(); | |
809 | } | |
810 | ||
10246fa3 SRRH |
811 | /** |
812 | * tracer_tracing_is_on - show real state of ring buffer enabled | |
813 | * @tr : the trace array to know if ring buffer is enabled | |
814 | * | |
815 | * Shows real state of the ring buffer if it is enabled or not. | |
816 | */ | |
5280bcef | 817 | static int tracer_tracing_is_on(struct trace_array *tr) |
10246fa3 SRRH |
818 | { |
819 | if (tr->trace_buffer.buffer) | |
820 | return ring_buffer_record_is_on(tr->trace_buffer.buffer); | |
821 | return !tr->buffer_disabled; | |
822 | } | |
823 | ||
499e5470 SR |
824 | /** |
825 | * tracing_is_on - show state of ring buffers enabled | |
826 | */ | |
827 | int tracing_is_on(void) | |
828 | { | |
10246fa3 | 829 | return tracer_tracing_is_on(&global_trace); |
499e5470 SR |
830 | } |
831 | EXPORT_SYMBOL_GPL(tracing_is_on); | |
832 | ||
3928a8a2 | 833 | static int __init set_buf_size(char *str) |
bc0c38d1 | 834 | { |
3928a8a2 | 835 | unsigned long buf_size; |
c6caeeb1 | 836 | |
bc0c38d1 SR |
837 | if (!str) |
838 | return 0; | |
9d612bef | 839 | buf_size = memparse(str, &str); |
c6caeeb1 | 840 | /* nr_entries can not be zero */ |
9d612bef | 841 | if (buf_size == 0) |
c6caeeb1 | 842 | return 0; |
3928a8a2 | 843 | trace_buf_size = buf_size; |
bc0c38d1 SR |
844 | return 1; |
845 | } | |
3928a8a2 | 846 | __setup("trace_buf_size=", set_buf_size); |
bc0c38d1 | 847 | |
0e950173 TB |
848 | static int __init set_tracing_thresh(char *str) |
849 | { | |
87abb3b1 | 850 | unsigned long threshold; |
0e950173 TB |
851 | int ret; |
852 | ||
853 | if (!str) | |
854 | return 0; | |
bcd83ea6 | 855 | ret = kstrtoul(str, 0, &threshold); |
0e950173 TB |
856 | if (ret < 0) |
857 | return 0; | |
87abb3b1 | 858 | tracing_thresh = threshold * 1000; |
0e950173 TB |
859 | return 1; |
860 | } | |
861 | __setup("tracing_thresh=", set_tracing_thresh); | |
862 | ||
57f50be1 SR |
863 | unsigned long nsecs_to_usecs(unsigned long nsecs) |
864 | { | |
865 | return nsecs / 1000; | |
866 | } | |
867 | ||
a3418a36 SRRH |
868 | /* |
869 | * TRACE_FLAGS is defined as a tuple matching bit masks with strings. | |
870 | * It uses C(a, b) where 'a' is the enum name and 'b' is the string that | |
871 | * matches it. By defining "C(a, b) b", TRACE_FLAGS becomes a list | |
872 | * of strings in the order that the enums were defined. | |
873 | */ | |
874 | #undef C | |
875 | #define C(a, b) b | |
876 | ||
4fcdae83 | 877 | /* These must match the bit postions in trace_iterator_flags */ |
bc0c38d1 | 878 | static const char *trace_options[] = { |
a3418a36 | 879 | TRACE_FLAGS |
bc0c38d1 SR |
880 | NULL |
881 | }; | |
882 | ||
5079f326 Z |
883 | static struct { |
884 | u64 (*func)(void); | |
885 | const char *name; | |
8be0709f | 886 | int in_ns; /* is this clock in nanoseconds? */ |
5079f326 | 887 | } trace_clocks[] = { |
1b3e5c09 TG |
888 | { trace_clock_local, "local", 1 }, |
889 | { trace_clock_global, "global", 1 }, | |
890 | { trace_clock_counter, "counter", 0 }, | |
e7fda6c4 | 891 | { trace_clock_jiffies, "uptime", 0 }, |
1b3e5c09 TG |
892 | { trace_clock, "perf", 1 }, |
893 | { ktime_get_mono_fast_ns, "mono", 1 }, | |
aabfa5f2 | 894 | { ktime_get_raw_fast_ns, "mono_raw", 1 }, |
8cbd9cc6 | 895 | ARCH_TRACE_CLOCKS |
5079f326 Z |
896 | }; |
897 | ||
b63f39ea | 898 | /* |
899 | * trace_parser_get_init - gets the buffer for trace parser | |
900 | */ | |
901 | int trace_parser_get_init(struct trace_parser *parser, int size) | |
902 | { | |
903 | memset(parser, 0, sizeof(*parser)); | |
904 | ||
905 | parser->buffer = kmalloc(size, GFP_KERNEL); | |
906 | if (!parser->buffer) | |
907 | return 1; | |
908 | ||
909 | parser->size = size; | |
910 | return 0; | |
911 | } | |
912 | ||
913 | /* | |
914 | * trace_parser_put - frees the buffer for trace parser | |
915 | */ | |
916 | void trace_parser_put(struct trace_parser *parser) | |
917 | { | |
918 | kfree(parser->buffer); | |
919 | } | |
920 | ||
921 | /* | |
922 | * trace_get_user - reads the user input string separated by space | |
923 | * (matched by isspace(ch)) | |
924 | * | |
925 | * For each string found the 'struct trace_parser' is updated, | |
926 | * and the function returns. | |
927 | * | |
928 | * Returns number of bytes read. | |
929 | * | |
930 | * See kernel/trace/trace.h for 'struct trace_parser' details. | |
931 | */ | |
932 | int trace_get_user(struct trace_parser *parser, const char __user *ubuf, | |
933 | size_t cnt, loff_t *ppos) | |
934 | { | |
935 | char ch; | |
936 | size_t read = 0; | |
937 | ssize_t ret; | |
938 | ||
939 | if (!*ppos) | |
940 | trace_parser_clear(parser); | |
941 | ||
942 | ret = get_user(ch, ubuf++); | |
943 | if (ret) | |
944 | goto out; | |
945 | ||
946 | read++; | |
947 | cnt--; | |
948 | ||
949 | /* | |
950 | * The parser is not finished with the last write, | |
951 | * continue reading the user input without skipping spaces. | |
952 | */ | |
953 | if (!parser->cont) { | |
954 | /* skip white space */ | |
955 | while (cnt && isspace(ch)) { | |
956 | ret = get_user(ch, ubuf++); | |
957 | if (ret) | |
958 | goto out; | |
959 | read++; | |
960 | cnt--; | |
961 | } | |
962 | ||
963 | /* only spaces were written */ | |
964 | if (isspace(ch)) { | |
965 | *ppos += read; | |
966 | ret = read; | |
967 | goto out; | |
968 | } | |
969 | ||
970 | parser->idx = 0; | |
971 | } | |
972 | ||
973 | /* read the non-space input */ | |
974 | while (cnt && !isspace(ch)) { | |
3c235a33 | 975 | if (parser->idx < parser->size - 1) |
b63f39ea | 976 | parser->buffer[parser->idx++] = ch; |
977 | else { | |
978 | ret = -EINVAL; | |
979 | goto out; | |
980 | } | |
981 | ret = get_user(ch, ubuf++); | |
982 | if (ret) | |
983 | goto out; | |
984 | read++; | |
985 | cnt--; | |
986 | } | |
987 | ||
988 | /* We either got finished input or we have to wait for another call. */ | |
989 | if (isspace(ch)) { | |
990 | parser->buffer[parser->idx] = 0; | |
991 | parser->cont = false; | |
057db848 | 992 | } else if (parser->idx < parser->size - 1) { |
b63f39ea | 993 | parser->cont = true; |
994 | parser->buffer[parser->idx++] = ch; | |
057db848 SR |
995 | } else { |
996 | ret = -EINVAL; | |
997 | goto out; | |
b63f39ea | 998 | } |
999 | ||
1000 | *ppos += read; | |
1001 | ret = read; | |
1002 | ||
1003 | out: | |
1004 | return ret; | |
1005 | } | |
1006 | ||
3a161d99 | 1007 | /* TODO add a seq_buf_to_buffer() */ |
b8b94265 | 1008 | static ssize_t trace_seq_to_buffer(struct trace_seq *s, void *buf, size_t cnt) |
3c56819b EGM |
1009 | { |
1010 | int len; | |
3c56819b | 1011 | |
5ac48378 | 1012 | if (trace_seq_used(s) <= s->seq.readpos) |
3c56819b EGM |
1013 | return -EBUSY; |
1014 | ||
5ac48378 | 1015 | len = trace_seq_used(s) - s->seq.readpos; |
3c56819b EGM |
1016 | if (cnt > len) |
1017 | cnt = len; | |
3a161d99 | 1018 | memcpy(buf, s->buffer + s->seq.readpos, cnt); |
3c56819b | 1019 | |
3a161d99 | 1020 | s->seq.readpos += cnt; |
3c56819b EGM |
1021 | return cnt; |
1022 | } | |
1023 | ||
0e950173 TB |
1024 | unsigned long __read_mostly tracing_thresh; |
1025 | ||
5d4a9dba | 1026 | #ifdef CONFIG_TRACER_MAX_TRACE |
5d4a9dba SR |
1027 | /* |
1028 | * Copy the new maximum trace into the separate maximum-trace | |
1029 | * structure. (this way the maximum trace is permanently saved, | |
1030 | * for later retrieval via /sys/kernel/debug/tracing/latency_trace) | |
1031 | */ | |
1032 | static void | |
1033 | __update_max_tr(struct trace_array *tr, struct task_struct *tsk, int cpu) | |
1034 | { | |
12883efb SRRH |
1035 | struct trace_buffer *trace_buf = &tr->trace_buffer; |
1036 | struct trace_buffer *max_buf = &tr->max_buffer; | |
1037 | struct trace_array_cpu *data = per_cpu_ptr(trace_buf->data, cpu); | |
1038 | struct trace_array_cpu *max_data = per_cpu_ptr(max_buf->data, cpu); | |
5d4a9dba | 1039 | |
12883efb SRRH |
1040 | max_buf->cpu = cpu; |
1041 | max_buf->time_start = data->preempt_timestamp; | |
5d4a9dba | 1042 | |
6d9b3fa5 | 1043 | max_data->saved_latency = tr->max_latency; |
8248ac05 SR |
1044 | max_data->critical_start = data->critical_start; |
1045 | max_data->critical_end = data->critical_end; | |
5d4a9dba | 1046 | |
1acaa1b2 | 1047 | memcpy(max_data->comm, tsk->comm, TASK_COMM_LEN); |
8248ac05 | 1048 | max_data->pid = tsk->pid; |
f17a5194 SRRH |
1049 | /* |
1050 | * If tsk == current, then use current_uid(), as that does not use | |
1051 | * RCU. The irq tracer can be called out of RCU scope. | |
1052 | */ | |
1053 | if (tsk == current) | |
1054 | max_data->uid = current_uid(); | |
1055 | else | |
1056 | max_data->uid = task_uid(tsk); | |
1057 | ||
8248ac05 SR |
1058 | max_data->nice = tsk->static_prio - 20 - MAX_RT_PRIO; |
1059 | max_data->policy = tsk->policy; | |
1060 | max_data->rt_priority = tsk->rt_priority; | |
5d4a9dba SR |
1061 | |
1062 | /* record this tasks comm */ | |
1063 | tracing_record_cmdline(tsk); | |
1064 | } | |
1065 | ||
4fcdae83 SR |
1066 | /** |
1067 | * update_max_tr - snapshot all trace buffers from global_trace to max_tr | |
1068 | * @tr: tracer | |
1069 | * @tsk: the task with the latency | |
1070 | * @cpu: The cpu that initiated the trace. | |
1071 | * | |
1072 | * Flip the buffers between the @tr and the max_tr and record information | |
1073 | * about which task was the cause of this latency. | |
1074 | */ | |
e309b41d | 1075 | void |
bc0c38d1 SR |
1076 | update_max_tr(struct trace_array *tr, struct task_struct *tsk, int cpu) |
1077 | { | |
2721e72d | 1078 | struct ring_buffer *buf; |
bc0c38d1 | 1079 | |
2b6080f2 | 1080 | if (tr->stop_count) |
b8de7bd1 SR |
1081 | return; |
1082 | ||
4c11d7ae | 1083 | WARN_ON_ONCE(!irqs_disabled()); |
34600f0e | 1084 | |
45ad21ca | 1085 | if (!tr->allocated_snapshot) { |
debdd57f | 1086 | /* Only the nop tracer should hit this when disabling */ |
2b6080f2 | 1087 | WARN_ON_ONCE(tr->current_trace != &nop_trace); |
34600f0e | 1088 | return; |
debdd57f | 1089 | } |
34600f0e | 1090 | |
0b9b12c1 | 1091 | arch_spin_lock(&tr->max_lock); |
3928a8a2 | 1092 | |
12883efb SRRH |
1093 | buf = tr->trace_buffer.buffer; |
1094 | tr->trace_buffer.buffer = tr->max_buffer.buffer; | |
1095 | tr->max_buffer.buffer = buf; | |
3928a8a2 | 1096 | |
bc0c38d1 | 1097 | __update_max_tr(tr, tsk, cpu); |
0b9b12c1 | 1098 | arch_spin_unlock(&tr->max_lock); |
bc0c38d1 SR |
1099 | } |
1100 | ||
1101 | /** | |
1102 | * update_max_tr_single - only copy one trace over, and reset the rest | |
1103 | * @tr - tracer | |
1104 | * @tsk - task with the latency | |
1105 | * @cpu - the cpu of the buffer to copy. | |
4fcdae83 SR |
1106 | * |
1107 | * Flip the trace of a single CPU buffer between the @tr and the max_tr. | |
bc0c38d1 | 1108 | */ |
e309b41d | 1109 | void |
bc0c38d1 SR |
1110 | update_max_tr_single(struct trace_array *tr, struct task_struct *tsk, int cpu) |
1111 | { | |
3928a8a2 | 1112 | int ret; |
bc0c38d1 | 1113 | |
2b6080f2 | 1114 | if (tr->stop_count) |
b8de7bd1 SR |
1115 | return; |
1116 | ||
4c11d7ae | 1117 | WARN_ON_ONCE(!irqs_disabled()); |
6c24499f | 1118 | if (!tr->allocated_snapshot) { |
2930e04d | 1119 | /* Only the nop tracer should hit this when disabling */ |
9e8529af | 1120 | WARN_ON_ONCE(tr->current_trace != &nop_trace); |
ef710e10 | 1121 | return; |
2930e04d | 1122 | } |
ef710e10 | 1123 | |
0b9b12c1 | 1124 | arch_spin_lock(&tr->max_lock); |
bc0c38d1 | 1125 | |
12883efb | 1126 | ret = ring_buffer_swap_cpu(tr->max_buffer.buffer, tr->trace_buffer.buffer, cpu); |
3928a8a2 | 1127 | |
e8165dbb SR |
1128 | if (ret == -EBUSY) { |
1129 | /* | |
1130 | * We failed to swap the buffer due to a commit taking | |
1131 | * place on this CPU. We fail to record, but we reset | |
1132 | * the max trace buffer (no one writes directly to it) | |
1133 | * and flag that it failed. | |
1134 | */ | |
12883efb | 1135 | trace_array_printk_buf(tr->max_buffer.buffer, _THIS_IP_, |
e8165dbb SR |
1136 | "Failed to swap buffers due to commit in progress\n"); |
1137 | } | |
1138 | ||
e8165dbb | 1139 | WARN_ON_ONCE(ret && ret != -EAGAIN && ret != -EBUSY); |
bc0c38d1 SR |
1140 | |
1141 | __update_max_tr(tr, tsk, cpu); | |
0b9b12c1 | 1142 | arch_spin_unlock(&tr->max_lock); |
bc0c38d1 | 1143 | } |
5d4a9dba | 1144 | #endif /* CONFIG_TRACER_MAX_TRACE */ |
bc0c38d1 | 1145 | |
e30f53aa | 1146 | static int wait_on_pipe(struct trace_iterator *iter, bool full) |
0d5c6e1c | 1147 | { |
15693458 SRRH |
1148 | /* Iterators are static, they should be filled or empty */ |
1149 | if (trace_buffer_iter(iter, iter->cpu_file)) | |
8b8b3683 | 1150 | return 0; |
0d5c6e1c | 1151 | |
e30f53aa RV |
1152 | return ring_buffer_wait(iter->trace_buffer->buffer, iter->cpu_file, |
1153 | full); | |
0d5c6e1c SR |
1154 | } |
1155 | ||
f4e781c0 SRRH |
1156 | #ifdef CONFIG_FTRACE_STARTUP_TEST |
1157 | static int run_tracer_selftest(struct tracer *type) | |
1158 | { | |
1159 | struct trace_array *tr = &global_trace; | |
1160 | struct tracer *saved_tracer = tr->current_trace; | |
1161 | int ret; | |
0d5c6e1c | 1162 | |
f4e781c0 SRRH |
1163 | if (!type->selftest || tracing_selftest_disabled) |
1164 | return 0; | |
0d5c6e1c SR |
1165 | |
1166 | /* | |
f4e781c0 SRRH |
1167 | * Run a selftest on this tracer. |
1168 | * Here we reset the trace buffer, and set the current | |
1169 | * tracer to be this tracer. The tracer can then run some | |
1170 | * internal tracing to verify that everything is in order. | |
1171 | * If we fail, we do not register this tracer. | |
0d5c6e1c | 1172 | */ |
f4e781c0 | 1173 | tracing_reset_online_cpus(&tr->trace_buffer); |
0d5c6e1c | 1174 | |
f4e781c0 SRRH |
1175 | tr->current_trace = type; |
1176 | ||
1177 | #ifdef CONFIG_TRACER_MAX_TRACE | |
1178 | if (type->use_max_tr) { | |
1179 | /* If we expanded the buffers, make sure the max is expanded too */ | |
1180 | if (ring_buffer_expanded) | |
1181 | ring_buffer_resize(tr->max_buffer.buffer, trace_buf_size, | |
1182 | RING_BUFFER_ALL_CPUS); | |
1183 | tr->allocated_snapshot = true; | |
1184 | } | |
1185 | #endif | |
1186 | ||
1187 | /* the test is responsible for initializing and enabling */ | |
1188 | pr_info("Testing tracer %s: ", type->name); | |
1189 | ret = type->selftest(type, tr); | |
1190 | /* the test is responsible for resetting too */ | |
1191 | tr->current_trace = saved_tracer; | |
1192 | if (ret) { | |
1193 | printk(KERN_CONT "FAILED!\n"); | |
1194 | /* Add the warning after printing 'FAILED' */ | |
1195 | WARN_ON(1); | |
1196 | return -1; | |
1197 | } | |
1198 | /* Only reset on passing, to avoid touching corrupted buffers */ | |
1199 | tracing_reset_online_cpus(&tr->trace_buffer); | |
1200 | ||
1201 | #ifdef CONFIG_TRACER_MAX_TRACE | |
1202 | if (type->use_max_tr) { | |
1203 | tr->allocated_snapshot = false; | |
0d5c6e1c | 1204 | |
f4e781c0 SRRH |
1205 | /* Shrink the max buffer again */ |
1206 | if (ring_buffer_expanded) | |
1207 | ring_buffer_resize(tr->max_buffer.buffer, 1, | |
1208 | RING_BUFFER_ALL_CPUS); | |
1209 | } | |
1210 | #endif | |
1211 | ||
1212 | printk(KERN_CONT "PASSED\n"); | |
1213 | return 0; | |
1214 | } | |
1215 | #else | |
1216 | static inline int run_tracer_selftest(struct tracer *type) | |
1217 | { | |
1218 | return 0; | |
0d5c6e1c | 1219 | } |
f4e781c0 | 1220 | #endif /* CONFIG_FTRACE_STARTUP_TEST */ |
0d5c6e1c | 1221 | |
41d9c0be SRRH |
1222 | static void add_tracer_options(struct trace_array *tr, struct tracer *t); |
1223 | ||
a4d1e688 JW |
1224 | static void __init apply_trace_boot_options(void); |
1225 | ||
4fcdae83 SR |
1226 | /** |
1227 | * register_tracer - register a tracer with the ftrace system. | |
1228 | * @type - the plugin for the tracer | |
1229 | * | |
1230 | * Register a new plugin tracer. | |
1231 | */ | |
a4d1e688 | 1232 | int __init register_tracer(struct tracer *type) |
bc0c38d1 SR |
1233 | { |
1234 | struct tracer *t; | |
bc0c38d1 SR |
1235 | int ret = 0; |
1236 | ||
1237 | if (!type->name) { | |
1238 | pr_info("Tracer must have a name\n"); | |
1239 | return -1; | |
1240 | } | |
1241 | ||
24a461d5 | 1242 | if (strlen(type->name) >= MAX_TRACER_SIZE) { |
ee6c2c1b LZ |
1243 | pr_info("Tracer has a name longer than %d\n", MAX_TRACER_SIZE); |
1244 | return -1; | |
1245 | } | |
1246 | ||
bc0c38d1 | 1247 | mutex_lock(&trace_types_lock); |
86fa2f60 | 1248 | |
8e1b82e0 FW |
1249 | tracing_selftest_running = true; |
1250 | ||
bc0c38d1 SR |
1251 | for (t = trace_types; t; t = t->next) { |
1252 | if (strcmp(type->name, t->name) == 0) { | |
1253 | /* already found */ | |
ee6c2c1b | 1254 | pr_info("Tracer %s already registered\n", |
bc0c38d1 SR |
1255 | type->name); |
1256 | ret = -1; | |
1257 | goto out; | |
1258 | } | |
1259 | } | |
1260 | ||
adf9f195 FW |
1261 | if (!type->set_flag) |
1262 | type->set_flag = &dummy_set_flag; | |
1263 | if (!type->flags) | |
1264 | type->flags = &dummy_tracer_flags; | |
1265 | else | |
1266 | if (!type->flags->opts) | |
1267 | type->flags->opts = dummy_tracer_opt; | |
6eaaa5d5 | 1268 | |
f4e781c0 SRRH |
1269 | ret = run_tracer_selftest(type); |
1270 | if (ret < 0) | |
1271 | goto out; | |
60a11774 | 1272 | |
bc0c38d1 SR |
1273 | type->next = trace_types; |
1274 | trace_types = type; | |
41d9c0be | 1275 | add_tracer_options(&global_trace, type); |
60a11774 | 1276 | |
bc0c38d1 | 1277 | out: |
8e1b82e0 | 1278 | tracing_selftest_running = false; |
bc0c38d1 SR |
1279 | mutex_unlock(&trace_types_lock); |
1280 | ||
dac74940 SR |
1281 | if (ret || !default_bootup_tracer) |
1282 | goto out_unlock; | |
1283 | ||
ee6c2c1b | 1284 | if (strncmp(default_bootup_tracer, type->name, MAX_TRACER_SIZE)) |
dac74940 SR |
1285 | goto out_unlock; |
1286 | ||
1287 | printk(KERN_INFO "Starting tracer '%s'\n", type->name); | |
1288 | /* Do we want this tracer to start on bootup? */ | |
607e2ea1 | 1289 | tracing_set_tracer(&global_trace, type->name); |
dac74940 | 1290 | default_bootup_tracer = NULL; |
a4d1e688 JW |
1291 | |
1292 | apply_trace_boot_options(); | |
1293 | ||
dac74940 | 1294 | /* disable other selftests, since this will break it. */ |
55034cd6 | 1295 | tracing_selftest_disabled = true; |
b2821ae6 | 1296 | #ifdef CONFIG_FTRACE_STARTUP_TEST |
dac74940 SR |
1297 | printk(KERN_INFO "Disabling FTRACE selftests due to running tracer '%s'\n", |
1298 | type->name); | |
b2821ae6 | 1299 | #endif |
b2821ae6 | 1300 | |
dac74940 | 1301 | out_unlock: |
bc0c38d1 SR |
1302 | return ret; |
1303 | } | |
1304 | ||
12883efb | 1305 | void tracing_reset(struct trace_buffer *buf, int cpu) |
f633903a | 1306 | { |
12883efb | 1307 | struct ring_buffer *buffer = buf->buffer; |
f633903a | 1308 | |
a5416411 HT |
1309 | if (!buffer) |
1310 | return; | |
1311 | ||
f633903a SR |
1312 | ring_buffer_record_disable(buffer); |
1313 | ||
1314 | /* Make sure all commits have finished */ | |
1315 | synchronize_sched(); | |
68179686 | 1316 | ring_buffer_reset_cpu(buffer, cpu); |
f633903a SR |
1317 | |
1318 | ring_buffer_record_enable(buffer); | |
1319 | } | |
1320 | ||
12883efb | 1321 | void tracing_reset_online_cpus(struct trace_buffer *buf) |
213cc060 | 1322 | { |
12883efb | 1323 | struct ring_buffer *buffer = buf->buffer; |
213cc060 PE |
1324 | int cpu; |
1325 | ||
a5416411 HT |
1326 | if (!buffer) |
1327 | return; | |
1328 | ||
621968cd SR |
1329 | ring_buffer_record_disable(buffer); |
1330 | ||
1331 | /* Make sure all commits have finished */ | |
1332 | synchronize_sched(); | |
1333 | ||
9457158b | 1334 | buf->time_start = buffer_ftrace_now(buf, buf->cpu); |
213cc060 PE |
1335 | |
1336 | for_each_online_cpu(cpu) | |
68179686 | 1337 | ring_buffer_reset_cpu(buffer, cpu); |
621968cd SR |
1338 | |
1339 | ring_buffer_record_enable(buffer); | |
213cc060 PE |
1340 | } |
1341 | ||
09d8091c | 1342 | /* Must have trace_types_lock held */ |
873c642f | 1343 | void tracing_reset_all_online_cpus(void) |
9456f0fa | 1344 | { |
873c642f SRRH |
1345 | struct trace_array *tr; |
1346 | ||
873c642f | 1347 | list_for_each_entry(tr, &ftrace_trace_arrays, list) { |
12883efb SRRH |
1348 | tracing_reset_online_cpus(&tr->trace_buffer); |
1349 | #ifdef CONFIG_TRACER_MAX_TRACE | |
1350 | tracing_reset_online_cpus(&tr->max_buffer); | |
1351 | #endif | |
873c642f | 1352 | } |
9456f0fa SR |
1353 | } |
1354 | ||
939c7a4f | 1355 | #define SAVED_CMDLINES_DEFAULT 128 |
2c7eea4c | 1356 | #define NO_CMDLINE_MAP UINT_MAX |
edc35bd7 | 1357 | static arch_spinlock_t trace_cmdline_lock = __ARCH_SPIN_LOCK_UNLOCKED; |
939c7a4f YY |
1358 | struct saved_cmdlines_buffer { |
1359 | unsigned map_pid_to_cmdline[PID_MAX_DEFAULT+1]; | |
1360 | unsigned *map_cmdline_to_pid; | |
1361 | unsigned cmdline_num; | |
1362 | int cmdline_idx; | |
1363 | char *saved_cmdlines; | |
1364 | }; | |
1365 | static struct saved_cmdlines_buffer *savedcmd; | |
25b0b44a | 1366 | |
25b0b44a | 1367 | /* temporary disable recording */ |
4fd27358 | 1368 | static atomic_t trace_record_cmdline_disabled __read_mostly; |
bc0c38d1 | 1369 | |
939c7a4f YY |
1370 | static inline char *get_saved_cmdlines(int idx) |
1371 | { | |
1372 | return &savedcmd->saved_cmdlines[idx * TASK_COMM_LEN]; | |
1373 | } | |
1374 | ||
1375 | static inline void set_cmdline(int idx, const char *cmdline) | |
bc0c38d1 | 1376 | { |
939c7a4f YY |
1377 | memcpy(get_saved_cmdlines(idx), cmdline, TASK_COMM_LEN); |
1378 | } | |
1379 | ||
1380 | static int allocate_cmdlines_buffer(unsigned int val, | |
1381 | struct saved_cmdlines_buffer *s) | |
1382 | { | |
1383 | s->map_cmdline_to_pid = kmalloc(val * sizeof(*s->map_cmdline_to_pid), | |
1384 | GFP_KERNEL); | |
1385 | if (!s->map_cmdline_to_pid) | |
1386 | return -ENOMEM; | |
1387 | ||
1388 | s->saved_cmdlines = kmalloc(val * TASK_COMM_LEN, GFP_KERNEL); | |
1389 | if (!s->saved_cmdlines) { | |
1390 | kfree(s->map_cmdline_to_pid); | |
1391 | return -ENOMEM; | |
1392 | } | |
1393 | ||
1394 | s->cmdline_idx = 0; | |
1395 | s->cmdline_num = val; | |
1396 | memset(&s->map_pid_to_cmdline, NO_CMDLINE_MAP, | |
1397 | sizeof(s->map_pid_to_cmdline)); | |
1398 | memset(s->map_cmdline_to_pid, NO_CMDLINE_MAP, | |
1399 | val * sizeof(*s->map_cmdline_to_pid)); | |
1400 | ||
1401 | return 0; | |
1402 | } | |
1403 | ||
1404 | static int trace_create_savedcmd(void) | |
1405 | { | |
1406 | int ret; | |
1407 | ||
a6af8fbf | 1408 | savedcmd = kmalloc(sizeof(*savedcmd), GFP_KERNEL); |
939c7a4f YY |
1409 | if (!savedcmd) |
1410 | return -ENOMEM; | |
1411 | ||
1412 | ret = allocate_cmdlines_buffer(SAVED_CMDLINES_DEFAULT, savedcmd); | |
1413 | if (ret < 0) { | |
1414 | kfree(savedcmd); | |
1415 | savedcmd = NULL; | |
1416 | return -ENOMEM; | |
1417 | } | |
1418 | ||
1419 | return 0; | |
bc0c38d1 SR |
1420 | } |
1421 | ||
b5130b1e CE |
1422 | int is_tracing_stopped(void) |
1423 | { | |
2b6080f2 | 1424 | return global_trace.stop_count; |
b5130b1e CE |
1425 | } |
1426 | ||
0f048701 SR |
1427 | /** |
1428 | * tracing_start - quick start of the tracer | |
1429 | * | |
1430 | * If tracing is enabled but was stopped by tracing_stop, | |
1431 | * this will start the tracer back up. | |
1432 | */ | |
1433 | void tracing_start(void) | |
1434 | { | |
1435 | struct ring_buffer *buffer; | |
1436 | unsigned long flags; | |
1437 | ||
1438 | if (tracing_disabled) | |
1439 | return; | |
1440 | ||
2b6080f2 SR |
1441 | raw_spin_lock_irqsave(&global_trace.start_lock, flags); |
1442 | if (--global_trace.stop_count) { | |
1443 | if (global_trace.stop_count < 0) { | |
b06a8301 SR |
1444 | /* Someone screwed up their debugging */ |
1445 | WARN_ON_ONCE(1); | |
2b6080f2 | 1446 | global_trace.stop_count = 0; |
b06a8301 | 1447 | } |
0f048701 SR |
1448 | goto out; |
1449 | } | |
1450 | ||
a2f80714 | 1451 | /* Prevent the buffers from switching */ |
0b9b12c1 | 1452 | arch_spin_lock(&global_trace.max_lock); |
0f048701 | 1453 | |
12883efb | 1454 | buffer = global_trace.trace_buffer.buffer; |
0f048701 SR |
1455 | if (buffer) |
1456 | ring_buffer_record_enable(buffer); | |
1457 | ||
12883efb SRRH |
1458 | #ifdef CONFIG_TRACER_MAX_TRACE |
1459 | buffer = global_trace.max_buffer.buffer; | |
0f048701 SR |
1460 | if (buffer) |
1461 | ring_buffer_record_enable(buffer); | |
12883efb | 1462 | #endif |
0f048701 | 1463 | |
0b9b12c1 | 1464 | arch_spin_unlock(&global_trace.max_lock); |
a2f80714 | 1465 | |
0f048701 | 1466 | out: |
2b6080f2 SR |
1467 | raw_spin_unlock_irqrestore(&global_trace.start_lock, flags); |
1468 | } | |
1469 | ||
1470 | static void tracing_start_tr(struct trace_array *tr) | |
1471 | { | |
1472 | struct ring_buffer *buffer; | |
1473 | unsigned long flags; | |
1474 | ||
1475 | if (tracing_disabled) | |
1476 | return; | |
1477 | ||
1478 | /* If global, we need to also start the max tracer */ | |
1479 | if (tr->flags & TRACE_ARRAY_FL_GLOBAL) | |
1480 | return tracing_start(); | |
1481 | ||
1482 | raw_spin_lock_irqsave(&tr->start_lock, flags); | |
1483 | ||
1484 | if (--tr->stop_count) { | |
1485 | if (tr->stop_count < 0) { | |
1486 | /* Someone screwed up their debugging */ | |
1487 | WARN_ON_ONCE(1); | |
1488 | tr->stop_count = 0; | |
1489 | } | |
1490 | goto out; | |
1491 | } | |
1492 | ||
12883efb | 1493 | buffer = tr->trace_buffer.buffer; |
2b6080f2 SR |
1494 | if (buffer) |
1495 | ring_buffer_record_enable(buffer); | |
1496 | ||
1497 | out: | |
1498 | raw_spin_unlock_irqrestore(&tr->start_lock, flags); | |
0f048701 SR |
1499 | } |
1500 | ||
1501 | /** | |
1502 | * tracing_stop - quick stop of the tracer | |
1503 | * | |
1504 | * Light weight way to stop tracing. Use in conjunction with | |
1505 | * tracing_start. | |
1506 | */ | |
1507 | void tracing_stop(void) | |
1508 | { | |
1509 | struct ring_buffer *buffer; | |
1510 | unsigned long flags; | |
1511 | ||
2b6080f2 SR |
1512 | raw_spin_lock_irqsave(&global_trace.start_lock, flags); |
1513 | if (global_trace.stop_count++) | |
0f048701 SR |
1514 | goto out; |
1515 | ||
a2f80714 | 1516 | /* Prevent the buffers from switching */ |
0b9b12c1 | 1517 | arch_spin_lock(&global_trace.max_lock); |
a2f80714 | 1518 | |
12883efb | 1519 | buffer = global_trace.trace_buffer.buffer; |
0f048701 SR |
1520 | if (buffer) |
1521 | ring_buffer_record_disable(buffer); | |
1522 | ||
12883efb SRRH |
1523 | #ifdef CONFIG_TRACER_MAX_TRACE |
1524 | buffer = global_trace.max_buffer.buffer; | |
0f048701 SR |
1525 | if (buffer) |
1526 | ring_buffer_record_disable(buffer); | |
12883efb | 1527 | #endif |
0f048701 | 1528 | |
0b9b12c1 | 1529 | arch_spin_unlock(&global_trace.max_lock); |
a2f80714 | 1530 | |
0f048701 | 1531 | out: |
2b6080f2 SR |
1532 | raw_spin_unlock_irqrestore(&global_trace.start_lock, flags); |
1533 | } | |
1534 | ||
1535 | static void tracing_stop_tr(struct trace_array *tr) | |
1536 | { | |
1537 | struct ring_buffer *buffer; | |
1538 | unsigned long flags; | |
1539 | ||
1540 | /* If global, we need to also stop the max tracer */ | |
1541 | if (tr->flags & TRACE_ARRAY_FL_GLOBAL) | |
1542 | return tracing_stop(); | |
1543 | ||
1544 | raw_spin_lock_irqsave(&tr->start_lock, flags); | |
1545 | if (tr->stop_count++) | |
1546 | goto out; | |
1547 | ||
12883efb | 1548 | buffer = tr->trace_buffer.buffer; |
2b6080f2 SR |
1549 | if (buffer) |
1550 | ring_buffer_record_disable(buffer); | |
1551 | ||
1552 | out: | |
1553 | raw_spin_unlock_irqrestore(&tr->start_lock, flags); | |
0f048701 SR |
1554 | } |
1555 | ||
e309b41d | 1556 | void trace_stop_cmdline_recording(void); |
bc0c38d1 | 1557 | |
379cfdac | 1558 | static int trace_save_cmdline(struct task_struct *tsk) |
bc0c38d1 | 1559 | { |
a635cf04 | 1560 | unsigned pid, idx; |
bc0c38d1 SR |
1561 | |
1562 | if (!tsk->pid || unlikely(tsk->pid > PID_MAX_DEFAULT)) | |
379cfdac | 1563 | return 0; |
bc0c38d1 SR |
1564 | |
1565 | /* | |
1566 | * It's not the end of the world if we don't get | |
1567 | * the lock, but we also don't want to spin | |
1568 | * nor do we want to disable interrupts, | |
1569 | * so if we miss here, then better luck next time. | |
1570 | */ | |
0199c4e6 | 1571 | if (!arch_spin_trylock(&trace_cmdline_lock)) |
379cfdac | 1572 | return 0; |
bc0c38d1 | 1573 | |
939c7a4f | 1574 | idx = savedcmd->map_pid_to_cmdline[tsk->pid]; |
2c7eea4c | 1575 | if (idx == NO_CMDLINE_MAP) { |
939c7a4f | 1576 | idx = (savedcmd->cmdline_idx + 1) % savedcmd->cmdline_num; |
bc0c38d1 | 1577 | |
a635cf04 CE |
1578 | /* |
1579 | * Check whether the cmdline buffer at idx has a pid | |
1580 | * mapped. We are going to overwrite that entry so we | |
1581 | * need to clear the map_pid_to_cmdline. Otherwise we | |
1582 | * would read the new comm for the old pid. | |
1583 | */ | |
939c7a4f | 1584 | pid = savedcmd->map_cmdline_to_pid[idx]; |
a635cf04 | 1585 | if (pid != NO_CMDLINE_MAP) |
939c7a4f | 1586 | savedcmd->map_pid_to_cmdline[pid] = NO_CMDLINE_MAP; |
bc0c38d1 | 1587 | |
939c7a4f YY |
1588 | savedcmd->map_cmdline_to_pid[idx] = tsk->pid; |
1589 | savedcmd->map_pid_to_cmdline[tsk->pid] = idx; | |
bc0c38d1 | 1590 | |
939c7a4f | 1591 | savedcmd->cmdline_idx = idx; |
bc0c38d1 SR |
1592 | } |
1593 | ||
939c7a4f | 1594 | set_cmdline(idx, tsk->comm); |
bc0c38d1 | 1595 | |
0199c4e6 | 1596 | arch_spin_unlock(&trace_cmdline_lock); |
379cfdac SRRH |
1597 | |
1598 | return 1; | |
bc0c38d1 SR |
1599 | } |
1600 | ||
4c27e756 | 1601 | static void __trace_find_cmdline(int pid, char comm[]) |
bc0c38d1 | 1602 | { |
bc0c38d1 SR |
1603 | unsigned map; |
1604 | ||
4ca53085 SR |
1605 | if (!pid) { |
1606 | strcpy(comm, "<idle>"); | |
1607 | return; | |
1608 | } | |
bc0c38d1 | 1609 | |
74bf4076 SR |
1610 | if (WARN_ON_ONCE(pid < 0)) { |
1611 | strcpy(comm, "<XXX>"); | |
1612 | return; | |
1613 | } | |
1614 | ||
4ca53085 SR |
1615 | if (pid > PID_MAX_DEFAULT) { |
1616 | strcpy(comm, "<...>"); | |
1617 | return; | |
1618 | } | |
bc0c38d1 | 1619 | |
939c7a4f | 1620 | map = savedcmd->map_pid_to_cmdline[pid]; |
50d88758 | 1621 | if (map != NO_CMDLINE_MAP) |
939c7a4f | 1622 | strcpy(comm, get_saved_cmdlines(map)); |
50d88758 TG |
1623 | else |
1624 | strcpy(comm, "<...>"); | |
4c27e756 SRRH |
1625 | } |
1626 | ||
1627 | void trace_find_cmdline(int pid, char comm[]) | |
1628 | { | |
1629 | preempt_disable(); | |
1630 | arch_spin_lock(&trace_cmdline_lock); | |
1631 | ||
1632 | __trace_find_cmdline(pid, comm); | |
bc0c38d1 | 1633 | |
0199c4e6 | 1634 | arch_spin_unlock(&trace_cmdline_lock); |
5b6045a9 | 1635 | preempt_enable(); |
bc0c38d1 SR |
1636 | } |
1637 | ||
e309b41d | 1638 | void tracing_record_cmdline(struct task_struct *tsk) |
bc0c38d1 | 1639 | { |
0fb9656d | 1640 | if (atomic_read(&trace_record_cmdline_disabled) || !tracing_is_on()) |
bc0c38d1 SR |
1641 | return; |
1642 | ||
7ffbd48d SR |
1643 | if (!__this_cpu_read(trace_cmdline_save)) |
1644 | return; | |
1645 | ||
379cfdac SRRH |
1646 | if (trace_save_cmdline(tsk)) |
1647 | __this_cpu_write(trace_cmdline_save, false); | |
bc0c38d1 SR |
1648 | } |
1649 | ||
45dcd8b8 | 1650 | void |
38697053 SR |
1651 | tracing_generic_entry_update(struct trace_entry *entry, unsigned long flags, |
1652 | int pc) | |
bc0c38d1 SR |
1653 | { |
1654 | struct task_struct *tsk = current; | |
bc0c38d1 | 1655 | |
777e208d SR |
1656 | entry->preempt_count = pc & 0xff; |
1657 | entry->pid = (tsk) ? tsk->pid : 0; | |
1658 | entry->flags = | |
9244489a | 1659 | #ifdef CONFIG_TRACE_IRQFLAGS_SUPPORT |
2e2ca155 | 1660 | (irqs_disabled_flags(flags) ? TRACE_FLAG_IRQS_OFF : 0) | |
9244489a SR |
1661 | #else |
1662 | TRACE_FLAG_IRQS_NOSUPPORT | | |
1663 | #endif | |
bc0c38d1 SR |
1664 | ((pc & HARDIRQ_MASK) ? TRACE_FLAG_HARDIRQ : 0) | |
1665 | ((pc & SOFTIRQ_MASK) ? TRACE_FLAG_SOFTIRQ : 0) | | |
e5137b50 PZ |
1666 | (tif_need_resched() ? TRACE_FLAG_NEED_RESCHED : 0) | |
1667 | (test_preempt_need_resched() ? TRACE_FLAG_PREEMPT_RESCHED : 0); | |
bc0c38d1 | 1668 | } |
f413cdb8 | 1669 | EXPORT_SYMBOL_GPL(tracing_generic_entry_update); |
bc0c38d1 | 1670 | |
e77405ad SR |
1671 | struct ring_buffer_event * |
1672 | trace_buffer_lock_reserve(struct ring_buffer *buffer, | |
1673 | int type, | |
1674 | unsigned long len, | |
1675 | unsigned long flags, int pc) | |
51a763dd ACM |
1676 | { |
1677 | struct ring_buffer_event *event; | |
1678 | ||
e77405ad | 1679 | event = ring_buffer_lock_reserve(buffer, len); |
51a763dd ACM |
1680 | if (event != NULL) { |
1681 | struct trace_entry *ent = ring_buffer_event_data(event); | |
1682 | ||
1683 | tracing_generic_entry_update(ent, flags, pc); | |
1684 | ent->type = type; | |
1685 | } | |
1686 | ||
1687 | return event; | |
1688 | } | |
51a763dd | 1689 | |
7ffbd48d SR |
1690 | void |
1691 | __buffer_unlock_commit(struct ring_buffer *buffer, struct ring_buffer_event *event) | |
1692 | { | |
1693 | __this_cpu_write(trace_cmdline_save, true); | |
1694 | ring_buffer_unlock_commit(buffer, event); | |
1695 | } | |
1696 | ||
b7f0c959 SRRH |
1697 | void trace_buffer_unlock_commit(struct trace_array *tr, |
1698 | struct ring_buffer *buffer, | |
1699 | struct ring_buffer_event *event, | |
1700 | unsigned long flags, int pc) | |
51a763dd | 1701 | { |
7ffbd48d | 1702 | __buffer_unlock_commit(buffer, event); |
51a763dd | 1703 | |
2d34f489 | 1704 | ftrace_trace_stack(tr, buffer, flags, 6, pc, NULL); |
e77405ad | 1705 | ftrace_trace_userstack(buffer, flags, pc); |
07edf712 | 1706 | } |
0d5c6e1c | 1707 | EXPORT_SYMBOL_GPL(trace_buffer_unlock_commit); |
51a763dd | 1708 | |
2c4a33ab SRRH |
1709 | static struct ring_buffer *temp_buffer; |
1710 | ||
ccb469a1 SR |
1711 | struct ring_buffer_event * |
1712 | trace_event_buffer_lock_reserve(struct ring_buffer **current_rb, | |
7f1d2f82 | 1713 | struct trace_event_file *trace_file, |
ccb469a1 SR |
1714 | int type, unsigned long len, |
1715 | unsigned long flags, int pc) | |
1716 | { | |
2c4a33ab SRRH |
1717 | struct ring_buffer_event *entry; |
1718 | ||
7f1d2f82 | 1719 | *current_rb = trace_file->tr->trace_buffer.buffer; |
2c4a33ab | 1720 | entry = trace_buffer_lock_reserve(*current_rb, |
ccb469a1 | 1721 | type, len, flags, pc); |
2c4a33ab SRRH |
1722 | /* |
1723 | * If tracing is off, but we have triggers enabled | |
1724 | * we still need to look at the event data. Use the temp_buffer | |
1725 | * to store the trace event for the tigger to use. It's recusive | |
1726 | * safe and will not be recorded anywhere. | |
1727 | */ | |
5d6ad960 | 1728 | if (!entry && trace_file->flags & EVENT_FILE_FL_TRIGGER_COND) { |
2c4a33ab SRRH |
1729 | *current_rb = temp_buffer; |
1730 | entry = trace_buffer_lock_reserve(*current_rb, | |
1731 | type, len, flags, pc); | |
1732 | } | |
1733 | return entry; | |
ccb469a1 SR |
1734 | } |
1735 | EXPORT_SYMBOL_GPL(trace_event_buffer_lock_reserve); | |
1736 | ||
ef5580d0 | 1737 | struct ring_buffer_event * |
e77405ad SR |
1738 | trace_current_buffer_lock_reserve(struct ring_buffer **current_rb, |
1739 | int type, unsigned long len, | |
ef5580d0 SR |
1740 | unsigned long flags, int pc) |
1741 | { | |
12883efb | 1742 | *current_rb = global_trace.trace_buffer.buffer; |
e77405ad | 1743 | return trace_buffer_lock_reserve(*current_rb, |
ef5580d0 SR |
1744 | type, len, flags, pc); |
1745 | } | |
94487d6d | 1746 | EXPORT_SYMBOL_GPL(trace_current_buffer_lock_reserve); |
ef5580d0 | 1747 | |
b7f0c959 SRRH |
1748 | void trace_buffer_unlock_commit_regs(struct trace_array *tr, |
1749 | struct ring_buffer *buffer, | |
0d5c6e1c SR |
1750 | struct ring_buffer_event *event, |
1751 | unsigned long flags, int pc, | |
1752 | struct pt_regs *regs) | |
1fd8df2c | 1753 | { |
7ffbd48d | 1754 | __buffer_unlock_commit(buffer, event); |
1fd8df2c | 1755 | |
2d34f489 | 1756 | ftrace_trace_stack(tr, buffer, flags, 6, pc, regs); |
1fd8df2c MH |
1757 | ftrace_trace_userstack(buffer, flags, pc); |
1758 | } | |
0d5c6e1c | 1759 | EXPORT_SYMBOL_GPL(trace_buffer_unlock_commit_regs); |
1fd8df2c | 1760 | |
e77405ad SR |
1761 | void trace_current_buffer_discard_commit(struct ring_buffer *buffer, |
1762 | struct ring_buffer_event *event) | |
77d9f465 | 1763 | { |
e77405ad | 1764 | ring_buffer_discard_commit(buffer, event); |
ef5580d0 | 1765 | } |
12acd473 | 1766 | EXPORT_SYMBOL_GPL(trace_current_buffer_discard_commit); |
ef5580d0 | 1767 | |
e309b41d | 1768 | void |
7be42151 | 1769 | trace_function(struct trace_array *tr, |
38697053 SR |
1770 | unsigned long ip, unsigned long parent_ip, unsigned long flags, |
1771 | int pc) | |
bc0c38d1 | 1772 | { |
2425bcb9 | 1773 | struct trace_event_call *call = &event_function; |
12883efb | 1774 | struct ring_buffer *buffer = tr->trace_buffer.buffer; |
3928a8a2 | 1775 | struct ring_buffer_event *event; |
777e208d | 1776 | struct ftrace_entry *entry; |
bc0c38d1 | 1777 | |
d769041f | 1778 | /* If we are reading the ring buffer, don't trace */ |
dd17c8f7 | 1779 | if (unlikely(__this_cpu_read(ftrace_cpu_disabled))) |
d769041f SR |
1780 | return; |
1781 | ||
e77405ad | 1782 | event = trace_buffer_lock_reserve(buffer, TRACE_FN, sizeof(*entry), |
51a763dd | 1783 | flags, pc); |
3928a8a2 SR |
1784 | if (!event) |
1785 | return; | |
1786 | entry = ring_buffer_event_data(event); | |
777e208d SR |
1787 | entry->ip = ip; |
1788 | entry->parent_ip = parent_ip; | |
e1112b4d | 1789 | |
f306cc82 | 1790 | if (!call_filter_check_discard(call, entry, buffer, event)) |
7ffbd48d | 1791 | __buffer_unlock_commit(buffer, event); |
bc0c38d1 SR |
1792 | } |
1793 | ||
c0a0d0d3 | 1794 | #ifdef CONFIG_STACKTRACE |
4a9bd3f1 SR |
1795 | |
1796 | #define FTRACE_STACK_MAX_ENTRIES (PAGE_SIZE / sizeof(unsigned long)) | |
1797 | struct ftrace_stack { | |
1798 | unsigned long calls[FTRACE_STACK_MAX_ENTRIES]; | |
1799 | }; | |
1800 | ||
1801 | static DEFINE_PER_CPU(struct ftrace_stack, ftrace_stack); | |
1802 | static DEFINE_PER_CPU(int, ftrace_stack_reserve); | |
1803 | ||
e77405ad | 1804 | static void __ftrace_trace_stack(struct ring_buffer *buffer, |
53614991 | 1805 | unsigned long flags, |
1fd8df2c | 1806 | int skip, int pc, struct pt_regs *regs) |
86387f7e | 1807 | { |
2425bcb9 | 1808 | struct trace_event_call *call = &event_kernel_stack; |
3928a8a2 | 1809 | struct ring_buffer_event *event; |
777e208d | 1810 | struct stack_entry *entry; |
86387f7e | 1811 | struct stack_trace trace; |
4a9bd3f1 SR |
1812 | int use_stack; |
1813 | int size = FTRACE_STACK_ENTRIES; | |
1814 | ||
1815 | trace.nr_entries = 0; | |
1816 | trace.skip = skip; | |
1817 | ||
1818 | /* | |
1819 | * Since events can happen in NMIs there's no safe way to | |
1820 | * use the per cpu ftrace_stacks. We reserve it and if an interrupt | |
1821 | * or NMI comes in, it will just have to use the default | |
1822 | * FTRACE_STACK_SIZE. | |
1823 | */ | |
1824 | preempt_disable_notrace(); | |
1825 | ||
82146529 | 1826 | use_stack = __this_cpu_inc_return(ftrace_stack_reserve); |
4a9bd3f1 SR |
1827 | /* |
1828 | * We don't need any atomic variables, just a barrier. | |
1829 | * If an interrupt comes in, we don't care, because it would | |
1830 | * have exited and put the counter back to what we want. | |
1831 | * We just need a barrier to keep gcc from moving things | |
1832 | * around. | |
1833 | */ | |
1834 | barrier(); | |
1835 | if (use_stack == 1) { | |
bdffd893 | 1836 | trace.entries = this_cpu_ptr(ftrace_stack.calls); |
4a9bd3f1 SR |
1837 | trace.max_entries = FTRACE_STACK_MAX_ENTRIES; |
1838 | ||
1839 | if (regs) | |
1840 | save_stack_trace_regs(regs, &trace); | |
1841 | else | |
1842 | save_stack_trace(&trace); | |
1843 | ||
1844 | if (trace.nr_entries > size) | |
1845 | size = trace.nr_entries; | |
1846 | } else | |
1847 | /* From now on, use_stack is a boolean */ | |
1848 | use_stack = 0; | |
1849 | ||
1850 | size *= sizeof(unsigned long); | |
86387f7e | 1851 | |
e77405ad | 1852 | event = trace_buffer_lock_reserve(buffer, TRACE_STACK, |
4a9bd3f1 | 1853 | sizeof(*entry) + size, flags, pc); |
3928a8a2 | 1854 | if (!event) |
4a9bd3f1 SR |
1855 | goto out; |
1856 | entry = ring_buffer_event_data(event); | |
86387f7e | 1857 | |
4a9bd3f1 SR |
1858 | memset(&entry->caller, 0, size); |
1859 | ||
1860 | if (use_stack) | |
1861 | memcpy(&entry->caller, trace.entries, | |
1862 | trace.nr_entries * sizeof(unsigned long)); | |
1863 | else { | |
1864 | trace.max_entries = FTRACE_STACK_ENTRIES; | |
1865 | trace.entries = entry->caller; | |
1866 | if (regs) | |
1867 | save_stack_trace_regs(regs, &trace); | |
1868 | else | |
1869 | save_stack_trace(&trace); | |
1870 | } | |
1871 | ||
1872 | entry->size = trace.nr_entries; | |
86387f7e | 1873 | |
f306cc82 | 1874 | if (!call_filter_check_discard(call, entry, buffer, event)) |
7ffbd48d | 1875 | __buffer_unlock_commit(buffer, event); |
4a9bd3f1 SR |
1876 | |
1877 | out: | |
1878 | /* Again, don't let gcc optimize things here */ | |
1879 | barrier(); | |
82146529 | 1880 | __this_cpu_dec(ftrace_stack_reserve); |
4a9bd3f1 SR |
1881 | preempt_enable_notrace(); |
1882 | ||
f0a920d5 IM |
1883 | } |
1884 | ||
2d34f489 SRRH |
1885 | static inline void ftrace_trace_stack(struct trace_array *tr, |
1886 | struct ring_buffer *buffer, | |
73dddbb5 SRRH |
1887 | unsigned long flags, |
1888 | int skip, int pc, struct pt_regs *regs) | |
53614991 | 1889 | { |
2d34f489 | 1890 | if (!(tr->trace_flags & TRACE_ITER_STACKTRACE)) |
53614991 SR |
1891 | return; |
1892 | ||
73dddbb5 | 1893 | __ftrace_trace_stack(buffer, flags, skip, pc, regs); |
53614991 SR |
1894 | } |
1895 | ||
c0a0d0d3 FW |
1896 | void __trace_stack(struct trace_array *tr, unsigned long flags, int skip, |
1897 | int pc) | |
38697053 | 1898 | { |
12883efb | 1899 | __ftrace_trace_stack(tr->trace_buffer.buffer, flags, skip, pc, NULL); |
38697053 SR |
1900 | } |
1901 | ||
03889384 SR |
1902 | /** |
1903 | * trace_dump_stack - record a stack back trace in the trace buffer | |
c142be8e | 1904 | * @skip: Number of functions to skip (helper handlers) |
03889384 | 1905 | */ |
c142be8e | 1906 | void trace_dump_stack(int skip) |
03889384 SR |
1907 | { |
1908 | unsigned long flags; | |
1909 | ||
1910 | if (tracing_disabled || tracing_selftest_running) | |
e36c5458 | 1911 | return; |
03889384 SR |
1912 | |
1913 | local_save_flags(flags); | |
1914 | ||
c142be8e SRRH |
1915 | /* |
1916 | * Skip 3 more, seems to get us at the caller of | |
1917 | * this function. | |
1918 | */ | |
1919 | skip += 3; | |
1920 | __ftrace_trace_stack(global_trace.trace_buffer.buffer, | |
1921 | flags, skip, preempt_count(), NULL); | |
03889384 SR |
1922 | } |
1923 | ||
91e86e56 SR |
1924 | static DEFINE_PER_CPU(int, user_stack_count); |
1925 | ||
e77405ad SR |
1926 | void |
1927 | ftrace_trace_userstack(struct ring_buffer *buffer, unsigned long flags, int pc) | |
02b67518 | 1928 | { |
2425bcb9 | 1929 | struct trace_event_call *call = &event_user_stack; |
8d7c6a96 | 1930 | struct ring_buffer_event *event; |
02b67518 TE |
1931 | struct userstack_entry *entry; |
1932 | struct stack_trace trace; | |
02b67518 | 1933 | |
983f938a | 1934 | if (!(global_trace.trace_flags & TRACE_ITER_USERSTACKTRACE)) |
02b67518 TE |
1935 | return; |
1936 | ||
b6345879 SR |
1937 | /* |
1938 | * NMIs can not handle page faults, even with fix ups. | |
1939 | * The save user stack can (and often does) fault. | |
1940 | */ | |
1941 | if (unlikely(in_nmi())) | |
1942 | return; | |
02b67518 | 1943 | |
91e86e56 SR |
1944 | /* |
1945 | * prevent recursion, since the user stack tracing may | |
1946 | * trigger other kernel events. | |
1947 | */ | |
1948 | preempt_disable(); | |
1949 | if (__this_cpu_read(user_stack_count)) | |
1950 | goto out; | |
1951 | ||
1952 | __this_cpu_inc(user_stack_count); | |
1953 | ||
e77405ad | 1954 | event = trace_buffer_lock_reserve(buffer, TRACE_USER_STACK, |
51a763dd | 1955 | sizeof(*entry), flags, pc); |
02b67518 | 1956 | if (!event) |
1dbd1951 | 1957 | goto out_drop_count; |
02b67518 | 1958 | entry = ring_buffer_event_data(event); |
02b67518 | 1959 | |
48659d31 | 1960 | entry->tgid = current->tgid; |
02b67518 TE |
1961 | memset(&entry->caller, 0, sizeof(entry->caller)); |
1962 | ||
1963 | trace.nr_entries = 0; | |
1964 | trace.max_entries = FTRACE_STACK_ENTRIES; | |
1965 | trace.skip = 0; | |
1966 | trace.entries = entry->caller; | |
1967 | ||
1968 | save_stack_trace_user(&trace); | |
f306cc82 | 1969 | if (!call_filter_check_discard(call, entry, buffer, event)) |
7ffbd48d | 1970 | __buffer_unlock_commit(buffer, event); |
91e86e56 | 1971 | |
1dbd1951 | 1972 | out_drop_count: |
91e86e56 | 1973 | __this_cpu_dec(user_stack_count); |
91e86e56 SR |
1974 | out: |
1975 | preempt_enable(); | |
02b67518 TE |
1976 | } |
1977 | ||
4fd27358 HE |
1978 | #ifdef UNUSED |
1979 | static void __trace_userstack(struct trace_array *tr, unsigned long flags) | |
02b67518 | 1980 | { |
7be42151 | 1981 | ftrace_trace_userstack(tr, flags, preempt_count()); |
02b67518 | 1982 | } |
4fd27358 | 1983 | #endif /* UNUSED */ |
02b67518 | 1984 | |
c0a0d0d3 FW |
1985 | #endif /* CONFIG_STACKTRACE */ |
1986 | ||
07d777fe SR |
1987 | /* created for use with alloc_percpu */ |
1988 | struct trace_buffer_struct { | |
1989 | char buffer[TRACE_BUF_SIZE]; | |
1990 | }; | |
1991 | ||
1992 | static struct trace_buffer_struct *trace_percpu_buffer; | |
1993 | static struct trace_buffer_struct *trace_percpu_sirq_buffer; | |
1994 | static struct trace_buffer_struct *trace_percpu_irq_buffer; | |
1995 | static struct trace_buffer_struct *trace_percpu_nmi_buffer; | |
1996 | ||
1997 | /* | |
1998 | * The buffer used is dependent on the context. There is a per cpu | |
1999 | * buffer for normal context, softirq contex, hard irq context and | |
2000 | * for NMI context. Thise allows for lockless recording. | |
2001 | * | |
2002 | * Note, if the buffers failed to be allocated, then this returns NULL | |
2003 | */ | |
2004 | static char *get_trace_buf(void) | |
2005 | { | |
2006 | struct trace_buffer_struct *percpu_buffer; | |
07d777fe SR |
2007 | |
2008 | /* | |
2009 | * If we have allocated per cpu buffers, then we do not | |
2010 | * need to do any locking. | |
2011 | */ | |
2012 | if (in_nmi()) | |
2013 | percpu_buffer = trace_percpu_nmi_buffer; | |
2014 | else if (in_irq()) | |
2015 | percpu_buffer = trace_percpu_irq_buffer; | |
2016 | else if (in_softirq()) | |
2017 | percpu_buffer = trace_percpu_sirq_buffer; | |
2018 | else | |
2019 | percpu_buffer = trace_percpu_buffer; | |
2020 | ||
2021 | if (!percpu_buffer) | |
2022 | return NULL; | |
2023 | ||
d8a0349c | 2024 | return this_cpu_ptr(&percpu_buffer->buffer[0]); |
07d777fe SR |
2025 | } |
2026 | ||
2027 | static int alloc_percpu_trace_buffer(void) | |
2028 | { | |
2029 | struct trace_buffer_struct *buffers; | |
2030 | struct trace_buffer_struct *sirq_buffers; | |
2031 | struct trace_buffer_struct *irq_buffers; | |
2032 | struct trace_buffer_struct *nmi_buffers; | |
2033 | ||
2034 | buffers = alloc_percpu(struct trace_buffer_struct); | |
2035 | if (!buffers) | |
2036 | goto err_warn; | |
2037 | ||
2038 | sirq_buffers = alloc_percpu(struct trace_buffer_struct); | |
2039 | if (!sirq_buffers) | |
2040 | goto err_sirq; | |
2041 | ||
2042 | irq_buffers = alloc_percpu(struct trace_buffer_struct); | |
2043 | if (!irq_buffers) | |
2044 | goto err_irq; | |
2045 | ||
2046 | nmi_buffers = alloc_percpu(struct trace_buffer_struct); | |
2047 | if (!nmi_buffers) | |
2048 | goto err_nmi; | |
2049 | ||
2050 | trace_percpu_buffer = buffers; | |
2051 | trace_percpu_sirq_buffer = sirq_buffers; | |
2052 | trace_percpu_irq_buffer = irq_buffers; | |
2053 | trace_percpu_nmi_buffer = nmi_buffers; | |
2054 | ||
2055 | return 0; | |
2056 | ||
2057 | err_nmi: | |
2058 | free_percpu(irq_buffers); | |
2059 | err_irq: | |
2060 | free_percpu(sirq_buffers); | |
2061 | err_sirq: | |
2062 | free_percpu(buffers); | |
2063 | err_warn: | |
2064 | WARN(1, "Could not allocate percpu trace_printk buffer"); | |
2065 | return -ENOMEM; | |
2066 | } | |
2067 | ||
81698831 SR |
2068 | static int buffers_allocated; |
2069 | ||
07d777fe SR |
2070 | void trace_printk_init_buffers(void) |
2071 | { | |
07d777fe SR |
2072 | if (buffers_allocated) |
2073 | return; | |
2074 | ||
2075 | if (alloc_percpu_trace_buffer()) | |
2076 | return; | |
2077 | ||
2184db46 SR |
2078 | /* trace_printk() is for debug use only. Don't use it in production. */ |
2079 | ||
69a1c994 BP |
2080 | pr_warning("\n"); |
2081 | pr_warning("**********************************************************\n"); | |
2184db46 SR |
2082 | pr_warning("** NOTICE NOTICE NOTICE NOTICE NOTICE NOTICE NOTICE **\n"); |
2083 | pr_warning("** **\n"); | |
2084 | pr_warning("** trace_printk() being used. Allocating extra memory. **\n"); | |
2085 | pr_warning("** **\n"); | |
2086 | pr_warning("** This means that this is a DEBUG kernel and it is **\n"); | |
eff264ef | 2087 | pr_warning("** unsafe for production use. **\n"); |
2184db46 SR |
2088 | pr_warning("** **\n"); |
2089 | pr_warning("** If you see this message and you are not debugging **\n"); | |
2090 | pr_warning("** the kernel, report this immediately to your vendor! **\n"); | |
2091 | pr_warning("** **\n"); | |
2092 | pr_warning("** NOTICE NOTICE NOTICE NOTICE NOTICE NOTICE NOTICE **\n"); | |
2093 | pr_warning("**********************************************************\n"); | |
07d777fe | 2094 | |
b382ede6 SR |
2095 | /* Expand the buffers to set size */ |
2096 | tracing_update_buffers(); | |
2097 | ||
07d777fe | 2098 | buffers_allocated = 1; |
81698831 SR |
2099 | |
2100 | /* | |
2101 | * trace_printk_init_buffers() can be called by modules. | |
2102 | * If that happens, then we need to start cmdline recording | |
2103 | * directly here. If the global_trace.buffer is already | |
2104 | * allocated here, then this was called by module code. | |
2105 | */ | |
12883efb | 2106 | if (global_trace.trace_buffer.buffer) |
81698831 SR |
2107 | tracing_start_cmdline_record(); |
2108 | } | |
2109 | ||
2110 | void trace_printk_start_comm(void) | |
2111 | { | |
2112 | /* Start tracing comms if trace printk is set */ | |
2113 | if (!buffers_allocated) | |
2114 | return; | |
2115 | tracing_start_cmdline_record(); | |
2116 | } | |
2117 | ||
2118 | static void trace_printk_start_stop_comm(int enabled) | |
2119 | { | |
2120 | if (!buffers_allocated) | |
2121 | return; | |
2122 | ||
2123 | if (enabled) | |
2124 | tracing_start_cmdline_record(); | |
2125 | else | |
2126 | tracing_stop_cmdline_record(); | |
07d777fe SR |
2127 | } |
2128 | ||
769b0441 | 2129 | /** |
48ead020 | 2130 | * trace_vbprintk - write binary msg to tracing buffer |
769b0441 FW |
2131 | * |
2132 | */ | |
40ce74f1 | 2133 | int trace_vbprintk(unsigned long ip, const char *fmt, va_list args) |
769b0441 | 2134 | { |
2425bcb9 | 2135 | struct trace_event_call *call = &event_bprint; |
769b0441 | 2136 | struct ring_buffer_event *event; |
e77405ad | 2137 | struct ring_buffer *buffer; |
769b0441 | 2138 | struct trace_array *tr = &global_trace; |
48ead020 | 2139 | struct bprint_entry *entry; |
769b0441 | 2140 | unsigned long flags; |
07d777fe SR |
2141 | char *tbuffer; |
2142 | int len = 0, size, pc; | |
769b0441 FW |
2143 | |
2144 | if (unlikely(tracing_selftest_running || tracing_disabled)) | |
2145 | return 0; | |
2146 | ||
2147 | /* Don't pollute graph traces with trace_vprintk internals */ | |
2148 | pause_graph_tracing(); | |
2149 | ||
2150 | pc = preempt_count(); | |
5168ae50 | 2151 | preempt_disable_notrace(); |
769b0441 | 2152 | |
07d777fe SR |
2153 | tbuffer = get_trace_buf(); |
2154 | if (!tbuffer) { | |
2155 | len = 0; | |
769b0441 | 2156 | goto out; |
07d777fe | 2157 | } |
769b0441 | 2158 | |
07d777fe | 2159 | len = vbin_printf((u32 *)tbuffer, TRACE_BUF_SIZE/sizeof(int), fmt, args); |
769b0441 | 2160 | |
07d777fe SR |
2161 | if (len > TRACE_BUF_SIZE/sizeof(int) || len < 0) |
2162 | goto out; | |
769b0441 | 2163 | |
07d777fe | 2164 | local_save_flags(flags); |
769b0441 | 2165 | size = sizeof(*entry) + sizeof(u32) * len; |
12883efb | 2166 | buffer = tr->trace_buffer.buffer; |
e77405ad SR |
2167 | event = trace_buffer_lock_reserve(buffer, TRACE_BPRINT, size, |
2168 | flags, pc); | |
769b0441 | 2169 | if (!event) |
07d777fe | 2170 | goto out; |
769b0441 FW |
2171 | entry = ring_buffer_event_data(event); |
2172 | entry->ip = ip; | |
769b0441 FW |
2173 | entry->fmt = fmt; |
2174 | ||
07d777fe | 2175 | memcpy(entry->buf, tbuffer, sizeof(u32) * len); |
f306cc82 | 2176 | if (!call_filter_check_discard(call, entry, buffer, event)) { |
7ffbd48d | 2177 | __buffer_unlock_commit(buffer, event); |
2d34f489 | 2178 | ftrace_trace_stack(tr, buffer, flags, 6, pc, NULL); |
d931369b | 2179 | } |
769b0441 | 2180 | |
769b0441 | 2181 | out: |
5168ae50 | 2182 | preempt_enable_notrace(); |
769b0441 FW |
2183 | unpause_graph_tracing(); |
2184 | ||
2185 | return len; | |
2186 | } | |
48ead020 FW |
2187 | EXPORT_SYMBOL_GPL(trace_vbprintk); |
2188 | ||
12883efb SRRH |
2189 | static int |
2190 | __trace_array_vprintk(struct ring_buffer *buffer, | |
2191 | unsigned long ip, const char *fmt, va_list args) | |
48ead020 | 2192 | { |
2425bcb9 | 2193 | struct trace_event_call *call = &event_print; |
48ead020 | 2194 | struct ring_buffer_event *event; |
07d777fe | 2195 | int len = 0, size, pc; |
48ead020 | 2196 | struct print_entry *entry; |
07d777fe SR |
2197 | unsigned long flags; |
2198 | char *tbuffer; | |
48ead020 FW |
2199 | |
2200 | if (tracing_disabled || tracing_selftest_running) | |
2201 | return 0; | |
2202 | ||
07d777fe SR |
2203 | /* Don't pollute graph traces with trace_vprintk internals */ |
2204 | pause_graph_tracing(); | |
2205 | ||
48ead020 FW |
2206 | pc = preempt_count(); |
2207 | preempt_disable_notrace(); | |
48ead020 | 2208 | |
07d777fe SR |
2209 | |
2210 | tbuffer = get_trace_buf(); | |
2211 | if (!tbuffer) { | |
2212 | len = 0; | |
48ead020 | 2213 | goto out; |
07d777fe | 2214 | } |
48ead020 | 2215 | |
3558a5ac | 2216 | len = vscnprintf(tbuffer, TRACE_BUF_SIZE, fmt, args); |
48ead020 | 2217 | |
07d777fe | 2218 | local_save_flags(flags); |
48ead020 | 2219 | size = sizeof(*entry) + len + 1; |
e77405ad | 2220 | event = trace_buffer_lock_reserve(buffer, TRACE_PRINT, size, |
07d777fe | 2221 | flags, pc); |
48ead020 | 2222 | if (!event) |
07d777fe | 2223 | goto out; |
48ead020 | 2224 | entry = ring_buffer_event_data(event); |
c13d2f7c | 2225 | entry->ip = ip; |
48ead020 | 2226 | |
3558a5ac | 2227 | memcpy(&entry->buf, tbuffer, len + 1); |
f306cc82 | 2228 | if (!call_filter_check_discard(call, entry, buffer, event)) { |
7ffbd48d | 2229 | __buffer_unlock_commit(buffer, event); |
2d34f489 | 2230 | ftrace_trace_stack(&global_trace, buffer, flags, 6, pc, NULL); |
d931369b | 2231 | } |
48ead020 FW |
2232 | out: |
2233 | preempt_enable_notrace(); | |
07d777fe | 2234 | unpause_graph_tracing(); |
48ead020 FW |
2235 | |
2236 | return len; | |
2237 | } | |
659372d3 | 2238 | |
12883efb SRRH |
2239 | int trace_array_vprintk(struct trace_array *tr, |
2240 | unsigned long ip, const char *fmt, va_list args) | |
2241 | { | |
2242 | return __trace_array_vprintk(tr->trace_buffer.buffer, ip, fmt, args); | |
2243 | } | |
2244 | ||
2245 | int trace_array_printk(struct trace_array *tr, | |
2246 | unsigned long ip, const char *fmt, ...) | |
2247 | { | |
2248 | int ret; | |
2249 | va_list ap; | |
2250 | ||
983f938a | 2251 | if (!(global_trace.trace_flags & TRACE_ITER_PRINTK)) |
12883efb SRRH |
2252 | return 0; |
2253 | ||
2254 | va_start(ap, fmt); | |
2255 | ret = trace_array_vprintk(tr, ip, fmt, ap); | |
2256 | va_end(ap); | |
2257 | return ret; | |
2258 | } | |
2259 | ||
2260 | int trace_array_printk_buf(struct ring_buffer *buffer, | |
2261 | unsigned long ip, const char *fmt, ...) | |
2262 | { | |
2263 | int ret; | |
2264 | va_list ap; | |
2265 | ||
983f938a | 2266 | if (!(global_trace.trace_flags & TRACE_ITER_PRINTK)) |
12883efb SRRH |
2267 | return 0; |
2268 | ||
2269 | va_start(ap, fmt); | |
2270 | ret = __trace_array_vprintk(buffer, ip, fmt, ap); | |
2271 | va_end(ap); | |
2272 | return ret; | |
2273 | } | |
2274 | ||
659372d3 SR |
2275 | int trace_vprintk(unsigned long ip, const char *fmt, va_list args) |
2276 | { | |
a813a159 | 2277 | return trace_array_vprintk(&global_trace, ip, fmt, args); |
659372d3 | 2278 | } |
769b0441 FW |
2279 | EXPORT_SYMBOL_GPL(trace_vprintk); |
2280 | ||
e2ac8ef5 | 2281 | static void trace_iterator_increment(struct trace_iterator *iter) |
5a90f577 | 2282 | { |
6d158a81 SR |
2283 | struct ring_buffer_iter *buf_iter = trace_buffer_iter(iter, iter->cpu); |
2284 | ||
5a90f577 | 2285 | iter->idx++; |
6d158a81 SR |
2286 | if (buf_iter) |
2287 | ring_buffer_read(buf_iter, NULL); | |
5a90f577 SR |
2288 | } |
2289 | ||
e309b41d | 2290 | static struct trace_entry * |
bc21b478 SR |
2291 | peek_next_entry(struct trace_iterator *iter, int cpu, u64 *ts, |
2292 | unsigned long *lost_events) | |
dd0e545f | 2293 | { |
3928a8a2 | 2294 | struct ring_buffer_event *event; |
6d158a81 | 2295 | struct ring_buffer_iter *buf_iter = trace_buffer_iter(iter, cpu); |
dd0e545f | 2296 | |
d769041f SR |
2297 | if (buf_iter) |
2298 | event = ring_buffer_iter_peek(buf_iter, ts); | |
2299 | else | |
12883efb | 2300 | event = ring_buffer_peek(iter->trace_buffer->buffer, cpu, ts, |
bc21b478 | 2301 | lost_events); |
d769041f | 2302 | |
4a9bd3f1 SR |
2303 | if (event) { |
2304 | iter->ent_size = ring_buffer_event_length(event); | |
2305 | return ring_buffer_event_data(event); | |
2306 | } | |
2307 | iter->ent_size = 0; | |
2308 | return NULL; | |
dd0e545f | 2309 | } |
d769041f | 2310 | |
dd0e545f | 2311 | static struct trace_entry * |
bc21b478 SR |
2312 | __find_next_entry(struct trace_iterator *iter, int *ent_cpu, |
2313 | unsigned long *missing_events, u64 *ent_ts) | |
bc0c38d1 | 2314 | { |
12883efb | 2315 | struct ring_buffer *buffer = iter->trace_buffer->buffer; |
bc0c38d1 | 2316 | struct trace_entry *ent, *next = NULL; |
aa27497c | 2317 | unsigned long lost_events = 0, next_lost = 0; |
b04cc6b1 | 2318 | int cpu_file = iter->cpu_file; |
3928a8a2 | 2319 | u64 next_ts = 0, ts; |
bc0c38d1 | 2320 | int next_cpu = -1; |
12b5da34 | 2321 | int next_size = 0; |
bc0c38d1 SR |
2322 | int cpu; |
2323 | ||
b04cc6b1 FW |
2324 | /* |
2325 | * If we are in a per_cpu trace file, don't bother by iterating over | |
2326 | * all cpu and peek directly. | |
2327 | */ | |
ae3b5093 | 2328 | if (cpu_file > RING_BUFFER_ALL_CPUS) { |
b04cc6b1 FW |
2329 | if (ring_buffer_empty_cpu(buffer, cpu_file)) |
2330 | return NULL; | |
bc21b478 | 2331 | ent = peek_next_entry(iter, cpu_file, ent_ts, missing_events); |
b04cc6b1 FW |
2332 | if (ent_cpu) |
2333 | *ent_cpu = cpu_file; | |
2334 | ||
2335 | return ent; | |
2336 | } | |
2337 | ||
ab46428c | 2338 | for_each_tracing_cpu(cpu) { |
dd0e545f | 2339 | |
3928a8a2 SR |
2340 | if (ring_buffer_empty_cpu(buffer, cpu)) |
2341 | continue; | |
dd0e545f | 2342 | |
bc21b478 | 2343 | ent = peek_next_entry(iter, cpu, &ts, &lost_events); |
dd0e545f | 2344 | |
cdd31cd2 IM |
2345 | /* |
2346 | * Pick the entry with the smallest timestamp: | |
2347 | */ | |
3928a8a2 | 2348 | if (ent && (!next || ts < next_ts)) { |
bc0c38d1 SR |
2349 | next = ent; |
2350 | next_cpu = cpu; | |
3928a8a2 | 2351 | next_ts = ts; |
bc21b478 | 2352 | next_lost = lost_events; |
12b5da34 | 2353 | next_size = iter->ent_size; |
bc0c38d1 SR |
2354 | } |
2355 | } | |
2356 | ||
12b5da34 SR |
2357 | iter->ent_size = next_size; |
2358 | ||
bc0c38d1 SR |
2359 | if (ent_cpu) |
2360 | *ent_cpu = next_cpu; | |
2361 | ||
3928a8a2 SR |
2362 | if (ent_ts) |
2363 | *ent_ts = next_ts; | |
2364 | ||
bc21b478 SR |
2365 | if (missing_events) |
2366 | *missing_events = next_lost; | |
2367 | ||
bc0c38d1 SR |
2368 | return next; |
2369 | } | |
2370 | ||
dd0e545f | 2371 | /* Find the next real entry, without updating the iterator itself */ |
c4a8e8be FW |
2372 | struct trace_entry *trace_find_next_entry(struct trace_iterator *iter, |
2373 | int *ent_cpu, u64 *ent_ts) | |
bc0c38d1 | 2374 | { |
bc21b478 | 2375 | return __find_next_entry(iter, ent_cpu, NULL, ent_ts); |
dd0e545f SR |
2376 | } |
2377 | ||
2378 | /* Find the next real entry, and increment the iterator to the next entry */ | |
955b61e5 | 2379 | void *trace_find_next_entry_inc(struct trace_iterator *iter) |
dd0e545f | 2380 | { |
bc21b478 SR |
2381 | iter->ent = __find_next_entry(iter, &iter->cpu, |
2382 | &iter->lost_events, &iter->ts); | |
dd0e545f | 2383 | |
3928a8a2 | 2384 | if (iter->ent) |
e2ac8ef5 | 2385 | trace_iterator_increment(iter); |
dd0e545f | 2386 | |
3928a8a2 | 2387 | return iter->ent ? iter : NULL; |
b3806b43 | 2388 | } |
bc0c38d1 | 2389 | |
e309b41d | 2390 | static void trace_consume(struct trace_iterator *iter) |
b3806b43 | 2391 | { |
12883efb | 2392 | ring_buffer_consume(iter->trace_buffer->buffer, iter->cpu, &iter->ts, |
bc21b478 | 2393 | &iter->lost_events); |
bc0c38d1 SR |
2394 | } |
2395 | ||
e309b41d | 2396 | static void *s_next(struct seq_file *m, void *v, loff_t *pos) |
bc0c38d1 SR |
2397 | { |
2398 | struct trace_iterator *iter = m->private; | |
bc0c38d1 | 2399 | int i = (int)*pos; |
4e3c3333 | 2400 | void *ent; |
bc0c38d1 | 2401 | |
a63ce5b3 SR |
2402 | WARN_ON_ONCE(iter->leftover); |
2403 | ||
bc0c38d1 SR |
2404 | (*pos)++; |
2405 | ||
2406 | /* can't go backwards */ | |
2407 | if (iter->idx > i) | |
2408 | return NULL; | |
2409 | ||
2410 | if (iter->idx < 0) | |
955b61e5 | 2411 | ent = trace_find_next_entry_inc(iter); |
bc0c38d1 SR |
2412 | else |
2413 | ent = iter; | |
2414 | ||
2415 | while (ent && iter->idx < i) | |
955b61e5 | 2416 | ent = trace_find_next_entry_inc(iter); |
bc0c38d1 SR |
2417 | |
2418 | iter->pos = *pos; | |
2419 | ||
bc0c38d1 SR |
2420 | return ent; |
2421 | } | |
2422 | ||
955b61e5 | 2423 | void tracing_iter_reset(struct trace_iterator *iter, int cpu) |
2f26ebd5 | 2424 | { |
2f26ebd5 SR |
2425 | struct ring_buffer_event *event; |
2426 | struct ring_buffer_iter *buf_iter; | |
2427 | unsigned long entries = 0; | |
2428 | u64 ts; | |
2429 | ||
12883efb | 2430 | per_cpu_ptr(iter->trace_buffer->data, cpu)->skipped_entries = 0; |
2f26ebd5 | 2431 | |
6d158a81 SR |
2432 | buf_iter = trace_buffer_iter(iter, cpu); |
2433 | if (!buf_iter) | |
2f26ebd5 SR |
2434 | return; |
2435 | ||
2f26ebd5 SR |
2436 | ring_buffer_iter_reset(buf_iter); |
2437 | ||
2438 | /* | |
2439 | * We could have the case with the max latency tracers | |
2440 | * that a reset never took place on a cpu. This is evident | |
2441 | * by the timestamp being before the start of the buffer. | |
2442 | */ | |
2443 | while ((event = ring_buffer_iter_peek(buf_iter, &ts))) { | |
12883efb | 2444 | if (ts >= iter->trace_buffer->time_start) |
2f26ebd5 SR |
2445 | break; |
2446 | entries++; | |
2447 | ring_buffer_read(buf_iter, NULL); | |
2448 | } | |
2449 | ||
12883efb | 2450 | per_cpu_ptr(iter->trace_buffer->data, cpu)->skipped_entries = entries; |
2f26ebd5 SR |
2451 | } |
2452 | ||
d7350c3f | 2453 | /* |
d7350c3f FW |
2454 | * The current tracer is copied to avoid a global locking |
2455 | * all around. | |
2456 | */ | |
bc0c38d1 SR |
2457 | static void *s_start(struct seq_file *m, loff_t *pos) |
2458 | { | |
2459 | struct trace_iterator *iter = m->private; | |
2b6080f2 | 2460 | struct trace_array *tr = iter->tr; |
b04cc6b1 | 2461 | int cpu_file = iter->cpu_file; |
bc0c38d1 SR |
2462 | void *p = NULL; |
2463 | loff_t l = 0; | |
3928a8a2 | 2464 | int cpu; |
bc0c38d1 | 2465 | |
2fd196ec HT |
2466 | /* |
2467 | * copy the tracer to avoid using a global lock all around. | |
2468 | * iter->trace is a copy of current_trace, the pointer to the | |
2469 | * name may be used instead of a strcmp(), as iter->trace->name | |
2470 | * will point to the same string as current_trace->name. | |
2471 | */ | |
bc0c38d1 | 2472 | mutex_lock(&trace_types_lock); |
2b6080f2 SR |
2473 | if (unlikely(tr->current_trace && iter->trace->name != tr->current_trace->name)) |
2474 | *iter->trace = *tr->current_trace; | |
d7350c3f | 2475 | mutex_unlock(&trace_types_lock); |
bc0c38d1 | 2476 | |
12883efb | 2477 | #ifdef CONFIG_TRACER_MAX_TRACE |
debdd57f HT |
2478 | if (iter->snapshot && iter->trace->use_max_tr) |
2479 | return ERR_PTR(-EBUSY); | |
12883efb | 2480 | #endif |
debdd57f HT |
2481 | |
2482 | if (!iter->snapshot) | |
2483 | atomic_inc(&trace_record_cmdline_disabled); | |
bc0c38d1 | 2484 | |
bc0c38d1 SR |
2485 | if (*pos != iter->pos) { |
2486 | iter->ent = NULL; | |
2487 | iter->cpu = 0; | |
2488 | iter->idx = -1; | |
2489 | ||
ae3b5093 | 2490 | if (cpu_file == RING_BUFFER_ALL_CPUS) { |
b04cc6b1 | 2491 | for_each_tracing_cpu(cpu) |
2f26ebd5 | 2492 | tracing_iter_reset(iter, cpu); |
b04cc6b1 | 2493 | } else |
2f26ebd5 | 2494 | tracing_iter_reset(iter, cpu_file); |
bc0c38d1 | 2495 | |
ac91d854 | 2496 | iter->leftover = 0; |
bc0c38d1 SR |
2497 | for (p = iter; p && l < *pos; p = s_next(m, p, &l)) |
2498 | ; | |
2499 | ||
2500 | } else { | |
a63ce5b3 SR |
2501 | /* |
2502 | * If we overflowed the seq_file before, then we want | |
2503 | * to just reuse the trace_seq buffer again. | |
2504 | */ | |
2505 | if (iter->leftover) | |
2506 | p = iter; | |
2507 | else { | |
2508 | l = *pos - 1; | |
2509 | p = s_next(m, p, &l); | |
2510 | } | |
bc0c38d1 SR |
2511 | } |
2512 | ||
4f535968 | 2513 | trace_event_read_lock(); |
7e53bd42 | 2514 | trace_access_lock(cpu_file); |
bc0c38d1 SR |
2515 | return p; |
2516 | } | |
2517 | ||
2518 | static void s_stop(struct seq_file *m, void *p) | |
2519 | { | |
7e53bd42 LJ |
2520 | struct trace_iterator *iter = m->private; |
2521 | ||
12883efb | 2522 | #ifdef CONFIG_TRACER_MAX_TRACE |
debdd57f HT |
2523 | if (iter->snapshot && iter->trace->use_max_tr) |
2524 | return; | |
12883efb | 2525 | #endif |
debdd57f HT |
2526 | |
2527 | if (!iter->snapshot) | |
2528 | atomic_dec(&trace_record_cmdline_disabled); | |
12883efb | 2529 | |
7e53bd42 | 2530 | trace_access_unlock(iter->cpu_file); |
4f535968 | 2531 | trace_event_read_unlock(); |
bc0c38d1 SR |
2532 | } |
2533 | ||
39eaf7ef | 2534 | static void |
12883efb SRRH |
2535 | get_total_entries(struct trace_buffer *buf, |
2536 | unsigned long *total, unsigned long *entries) | |
39eaf7ef SR |
2537 | { |
2538 | unsigned long count; | |
2539 | int cpu; | |
2540 | ||
2541 | *total = 0; | |
2542 | *entries = 0; | |
2543 | ||
2544 | for_each_tracing_cpu(cpu) { | |
12883efb | 2545 | count = ring_buffer_entries_cpu(buf->buffer, cpu); |
39eaf7ef SR |
2546 | /* |
2547 | * If this buffer has skipped entries, then we hold all | |
2548 | * entries for the trace and we need to ignore the | |
2549 | * ones before the time stamp. | |
2550 | */ | |
12883efb SRRH |
2551 | if (per_cpu_ptr(buf->data, cpu)->skipped_entries) { |
2552 | count -= per_cpu_ptr(buf->data, cpu)->skipped_entries; | |
39eaf7ef SR |
2553 | /* total is the same as the entries */ |
2554 | *total += count; | |
2555 | } else | |
2556 | *total += count + | |
12883efb | 2557 | ring_buffer_overrun_cpu(buf->buffer, cpu); |
39eaf7ef SR |
2558 | *entries += count; |
2559 | } | |
2560 | } | |
2561 | ||
e309b41d | 2562 | static void print_lat_help_header(struct seq_file *m) |
bc0c38d1 | 2563 | { |
d79ac28f RV |
2564 | seq_puts(m, "# _------=> CPU# \n" |
2565 | "# / _-----=> irqs-off \n" | |
2566 | "# | / _----=> need-resched \n" | |
2567 | "# || / _---=> hardirq/softirq \n" | |
2568 | "# ||| / _--=> preempt-depth \n" | |
2569 | "# |||| / delay \n" | |
2570 | "# cmd pid ||||| time | caller \n" | |
2571 | "# \\ / ||||| \\ | / \n"); | |
bc0c38d1 SR |
2572 | } |
2573 | ||
12883efb | 2574 | static void print_event_info(struct trace_buffer *buf, struct seq_file *m) |
bc0c38d1 | 2575 | { |
39eaf7ef SR |
2576 | unsigned long total; |
2577 | unsigned long entries; | |
2578 | ||
12883efb | 2579 | get_total_entries(buf, &total, &entries); |
39eaf7ef SR |
2580 | seq_printf(m, "# entries-in-buffer/entries-written: %lu/%lu #P:%d\n", |
2581 | entries, total, num_online_cpus()); | |
2582 | seq_puts(m, "#\n"); | |
2583 | } | |
2584 | ||
12883efb | 2585 | static void print_func_help_header(struct trace_buffer *buf, struct seq_file *m) |
39eaf7ef | 2586 | { |
12883efb | 2587 | print_event_info(buf, m); |
d79ac28f RV |
2588 | seq_puts(m, "# TASK-PID CPU# TIMESTAMP FUNCTION\n" |
2589 | "# | | | | |\n"); | |
bc0c38d1 SR |
2590 | } |
2591 | ||
12883efb | 2592 | static void print_func_help_header_irq(struct trace_buffer *buf, struct seq_file *m) |
77271ce4 | 2593 | { |
12883efb | 2594 | print_event_info(buf, m); |
d79ac28f RV |
2595 | seq_puts(m, "# _-----=> irqs-off\n" |
2596 | "# / _----=> need-resched\n" | |
2597 | "# | / _---=> hardirq/softirq\n" | |
2598 | "# || / _--=> preempt-depth\n" | |
2599 | "# ||| / delay\n" | |
2600 | "# TASK-PID CPU# |||| TIMESTAMP FUNCTION\n" | |
2601 | "# | | | |||| | |\n"); | |
77271ce4 | 2602 | } |
bc0c38d1 | 2603 | |
62b915f1 | 2604 | void |
bc0c38d1 SR |
2605 | print_trace_header(struct seq_file *m, struct trace_iterator *iter) |
2606 | { | |
983f938a | 2607 | unsigned long sym_flags = (global_trace.trace_flags & TRACE_ITER_SYM_MASK); |
12883efb SRRH |
2608 | struct trace_buffer *buf = iter->trace_buffer; |
2609 | struct trace_array_cpu *data = per_cpu_ptr(buf->data, buf->cpu); | |
2b6080f2 | 2610 | struct tracer *type = iter->trace; |
39eaf7ef SR |
2611 | unsigned long entries; |
2612 | unsigned long total; | |
bc0c38d1 SR |
2613 | const char *name = "preemption"; |
2614 | ||
d840f718 | 2615 | name = type->name; |
bc0c38d1 | 2616 | |
12883efb | 2617 | get_total_entries(buf, &total, &entries); |
bc0c38d1 | 2618 | |
888b55dc | 2619 | seq_printf(m, "# %s latency trace v1.1.5 on %s\n", |
bc0c38d1 | 2620 | name, UTS_RELEASE); |
888b55dc | 2621 | seq_puts(m, "# -----------------------------------" |
bc0c38d1 | 2622 | "---------------------------------\n"); |
888b55dc | 2623 | seq_printf(m, "# latency: %lu us, #%lu/%lu, CPU#%d |" |
bc0c38d1 | 2624 | " (M:%s VP:%d, KP:%d, SP:%d HP:%d", |
57f50be1 | 2625 | nsecs_to_usecs(data->saved_latency), |
bc0c38d1 | 2626 | entries, |
4c11d7ae | 2627 | total, |
12883efb | 2628 | buf->cpu, |
bc0c38d1 SR |
2629 | #if defined(CONFIG_PREEMPT_NONE) |
2630 | "server", | |
2631 | #elif defined(CONFIG_PREEMPT_VOLUNTARY) | |
2632 | "desktop", | |
b5c21b45 | 2633 | #elif defined(CONFIG_PREEMPT) |
bc0c38d1 SR |
2634 | "preempt", |
2635 | #else | |
2636 | "unknown", | |
2637 | #endif | |
2638 | /* These are reserved for later use */ | |
2639 | 0, 0, 0, 0); | |
2640 | #ifdef CONFIG_SMP | |
2641 | seq_printf(m, " #P:%d)\n", num_online_cpus()); | |
2642 | #else | |
2643 | seq_puts(m, ")\n"); | |
2644 | #endif | |
888b55dc KM |
2645 | seq_puts(m, "# -----------------\n"); |
2646 | seq_printf(m, "# | task: %.16s-%d " | |
bc0c38d1 | 2647 | "(uid:%d nice:%ld policy:%ld rt_prio:%ld)\n", |
d20b92ab EB |
2648 | data->comm, data->pid, |
2649 | from_kuid_munged(seq_user_ns(m), data->uid), data->nice, | |
bc0c38d1 | 2650 | data->policy, data->rt_priority); |
888b55dc | 2651 | seq_puts(m, "# -----------------\n"); |
bc0c38d1 SR |
2652 | |
2653 | if (data->critical_start) { | |
888b55dc | 2654 | seq_puts(m, "# => started at: "); |
214023c3 SR |
2655 | seq_print_ip_sym(&iter->seq, data->critical_start, sym_flags); |
2656 | trace_print_seq(m, &iter->seq); | |
888b55dc | 2657 | seq_puts(m, "\n# => ended at: "); |
214023c3 SR |
2658 | seq_print_ip_sym(&iter->seq, data->critical_end, sym_flags); |
2659 | trace_print_seq(m, &iter->seq); | |
8248ac05 | 2660 | seq_puts(m, "\n#\n"); |
bc0c38d1 SR |
2661 | } |
2662 | ||
888b55dc | 2663 | seq_puts(m, "#\n"); |
bc0c38d1 SR |
2664 | } |
2665 | ||
a309720c SR |
2666 | static void test_cpu_buff_start(struct trace_iterator *iter) |
2667 | { | |
2668 | struct trace_seq *s = &iter->seq; | |
983f938a | 2669 | struct trace_array *tr = iter->tr; |
a309720c | 2670 | |
983f938a | 2671 | if (!(tr->trace_flags & TRACE_ITER_ANNOTATE)) |
12ef7d44 SR |
2672 | return; |
2673 | ||
2674 | if (!(iter->iter_flags & TRACE_FILE_ANNOTATE)) | |
2675 | return; | |
2676 | ||
919cd979 | 2677 | if (iter->started && cpumask_test_cpu(iter->cpu, iter->started)) |
a309720c SR |
2678 | return; |
2679 | ||
12883efb | 2680 | if (per_cpu_ptr(iter->trace_buffer->data, iter->cpu)->skipped_entries) |
2f26ebd5 SR |
2681 | return; |
2682 | ||
919cd979 SL |
2683 | if (iter->started) |
2684 | cpumask_set_cpu(iter->cpu, iter->started); | |
b0dfa978 FW |
2685 | |
2686 | /* Don't print started cpu buffer for the first entry of the trace */ | |
2687 | if (iter->idx > 1) | |
2688 | trace_seq_printf(s, "##### CPU %u buffer started ####\n", | |
2689 | iter->cpu); | |
a309720c SR |
2690 | } |
2691 | ||
2c4f035f | 2692 | static enum print_line_t print_trace_fmt(struct trace_iterator *iter) |
bc0c38d1 | 2693 | { |
983f938a | 2694 | struct trace_array *tr = iter->tr; |
214023c3 | 2695 | struct trace_seq *s = &iter->seq; |
983f938a | 2696 | unsigned long sym_flags = (tr->trace_flags & TRACE_ITER_SYM_MASK); |
4e3c3333 | 2697 | struct trace_entry *entry; |
f633cef0 | 2698 | struct trace_event *event; |
bc0c38d1 | 2699 | |
4e3c3333 | 2700 | entry = iter->ent; |
dd0e545f | 2701 | |
a309720c SR |
2702 | test_cpu_buff_start(iter); |
2703 | ||
c4a8e8be | 2704 | event = ftrace_find_event(entry->type); |
bc0c38d1 | 2705 | |
983f938a | 2706 | if (tr->trace_flags & TRACE_ITER_CONTEXT_INFO) { |
19a7fe20 SRRH |
2707 | if (iter->iter_flags & TRACE_FILE_LAT_FMT) |
2708 | trace_print_lat_context(iter); | |
2709 | else | |
2710 | trace_print_context(iter); | |
c4a8e8be | 2711 | } |
bc0c38d1 | 2712 | |
19a7fe20 SRRH |
2713 | if (trace_seq_has_overflowed(s)) |
2714 | return TRACE_TYPE_PARTIAL_LINE; | |
2715 | ||
268ccda0 | 2716 | if (event) |
a9a57763 | 2717 | return event->funcs->trace(iter, sym_flags, event); |
d9793bd8 | 2718 | |
19a7fe20 | 2719 | trace_seq_printf(s, "Unknown type %d\n", entry->type); |
02b67518 | 2720 | |
19a7fe20 | 2721 | return trace_handle_return(s); |
bc0c38d1 SR |
2722 | } |
2723 | ||
2c4f035f | 2724 | static enum print_line_t print_raw_fmt(struct trace_iterator *iter) |
f9896bf3 | 2725 | { |
983f938a | 2726 | struct trace_array *tr = iter->tr; |
f9896bf3 IM |
2727 | struct trace_seq *s = &iter->seq; |
2728 | struct trace_entry *entry; | |
f633cef0 | 2729 | struct trace_event *event; |
f9896bf3 IM |
2730 | |
2731 | entry = iter->ent; | |
dd0e545f | 2732 | |
983f938a | 2733 | if (tr->trace_flags & TRACE_ITER_CONTEXT_INFO) |
19a7fe20 SRRH |
2734 | trace_seq_printf(s, "%d %d %llu ", |
2735 | entry->pid, iter->cpu, iter->ts); | |
2736 | ||
2737 | if (trace_seq_has_overflowed(s)) | |
2738 | return TRACE_TYPE_PARTIAL_LINE; | |
f9896bf3 | 2739 | |
f633cef0 | 2740 | event = ftrace_find_event(entry->type); |
268ccda0 | 2741 | if (event) |
a9a57763 | 2742 | return event->funcs->raw(iter, 0, event); |
d9793bd8 | 2743 | |
19a7fe20 | 2744 | trace_seq_printf(s, "%d ?\n", entry->type); |
777e208d | 2745 | |
19a7fe20 | 2746 | return trace_handle_return(s); |
f9896bf3 IM |
2747 | } |
2748 | ||
2c4f035f | 2749 | static enum print_line_t print_hex_fmt(struct trace_iterator *iter) |
5e3ca0ec | 2750 | { |
983f938a | 2751 | struct trace_array *tr = iter->tr; |
5e3ca0ec IM |
2752 | struct trace_seq *s = &iter->seq; |
2753 | unsigned char newline = '\n'; | |
2754 | struct trace_entry *entry; | |
f633cef0 | 2755 | struct trace_event *event; |
5e3ca0ec IM |
2756 | |
2757 | entry = iter->ent; | |
dd0e545f | 2758 | |
983f938a | 2759 | if (tr->trace_flags & TRACE_ITER_CONTEXT_INFO) { |
19a7fe20 SRRH |
2760 | SEQ_PUT_HEX_FIELD(s, entry->pid); |
2761 | SEQ_PUT_HEX_FIELD(s, iter->cpu); | |
2762 | SEQ_PUT_HEX_FIELD(s, iter->ts); | |
2763 | if (trace_seq_has_overflowed(s)) | |
2764 | return TRACE_TYPE_PARTIAL_LINE; | |
c4a8e8be | 2765 | } |
5e3ca0ec | 2766 | |
f633cef0 | 2767 | event = ftrace_find_event(entry->type); |
268ccda0 | 2768 | if (event) { |
a9a57763 | 2769 | enum print_line_t ret = event->funcs->hex(iter, 0, event); |
d9793bd8 ACM |
2770 | if (ret != TRACE_TYPE_HANDLED) |
2771 | return ret; | |
2772 | } | |
7104f300 | 2773 | |
19a7fe20 | 2774 | SEQ_PUT_FIELD(s, newline); |
5e3ca0ec | 2775 | |
19a7fe20 | 2776 | return trace_handle_return(s); |
5e3ca0ec IM |
2777 | } |
2778 | ||
2c4f035f | 2779 | static enum print_line_t print_bin_fmt(struct trace_iterator *iter) |
cb0f12aa | 2780 | { |
983f938a | 2781 | struct trace_array *tr = iter->tr; |
cb0f12aa IM |
2782 | struct trace_seq *s = &iter->seq; |
2783 | struct trace_entry *entry; | |
f633cef0 | 2784 | struct trace_event *event; |
cb0f12aa IM |
2785 | |
2786 | entry = iter->ent; | |
dd0e545f | 2787 | |
983f938a | 2788 | if (tr->trace_flags & TRACE_ITER_CONTEXT_INFO) { |
19a7fe20 SRRH |
2789 | SEQ_PUT_FIELD(s, entry->pid); |
2790 | SEQ_PUT_FIELD(s, iter->cpu); | |
2791 | SEQ_PUT_FIELD(s, iter->ts); | |
2792 | if (trace_seq_has_overflowed(s)) | |
2793 | return TRACE_TYPE_PARTIAL_LINE; | |
c4a8e8be | 2794 | } |
cb0f12aa | 2795 | |
f633cef0 | 2796 | event = ftrace_find_event(entry->type); |
a9a57763 SR |
2797 | return event ? event->funcs->binary(iter, 0, event) : |
2798 | TRACE_TYPE_HANDLED; | |
cb0f12aa IM |
2799 | } |
2800 | ||
62b915f1 | 2801 | int trace_empty(struct trace_iterator *iter) |
bc0c38d1 | 2802 | { |
6d158a81 | 2803 | struct ring_buffer_iter *buf_iter; |
bc0c38d1 SR |
2804 | int cpu; |
2805 | ||
9aba60fe | 2806 | /* If we are looking at one CPU buffer, only check that one */ |
ae3b5093 | 2807 | if (iter->cpu_file != RING_BUFFER_ALL_CPUS) { |
9aba60fe | 2808 | cpu = iter->cpu_file; |
6d158a81 SR |
2809 | buf_iter = trace_buffer_iter(iter, cpu); |
2810 | if (buf_iter) { | |
2811 | if (!ring_buffer_iter_empty(buf_iter)) | |
9aba60fe SR |
2812 | return 0; |
2813 | } else { | |
12883efb | 2814 | if (!ring_buffer_empty_cpu(iter->trace_buffer->buffer, cpu)) |
9aba60fe SR |
2815 | return 0; |
2816 | } | |
2817 | return 1; | |
2818 | } | |
2819 | ||
ab46428c | 2820 | for_each_tracing_cpu(cpu) { |
6d158a81 SR |
2821 | buf_iter = trace_buffer_iter(iter, cpu); |
2822 | if (buf_iter) { | |
2823 | if (!ring_buffer_iter_empty(buf_iter)) | |
d769041f SR |
2824 | return 0; |
2825 | } else { | |
12883efb | 2826 | if (!ring_buffer_empty_cpu(iter->trace_buffer->buffer, cpu)) |
d769041f SR |
2827 | return 0; |
2828 | } | |
bc0c38d1 | 2829 | } |
d769041f | 2830 | |
797d3712 | 2831 | return 1; |
bc0c38d1 SR |
2832 | } |
2833 | ||
4f535968 | 2834 | /* Called with trace_event_read_lock() held. */ |
955b61e5 | 2835 | enum print_line_t print_trace_line(struct trace_iterator *iter) |
f9896bf3 | 2836 | { |
983f938a SRRH |
2837 | struct trace_array *tr = iter->tr; |
2838 | unsigned long trace_flags = tr->trace_flags; | |
2c4f035f FW |
2839 | enum print_line_t ret; |
2840 | ||
19a7fe20 SRRH |
2841 | if (iter->lost_events) { |
2842 | trace_seq_printf(&iter->seq, "CPU:%d [LOST %lu EVENTS]\n", | |
2843 | iter->cpu, iter->lost_events); | |
2844 | if (trace_seq_has_overflowed(&iter->seq)) | |
2845 | return TRACE_TYPE_PARTIAL_LINE; | |
2846 | } | |
bc21b478 | 2847 | |
2c4f035f FW |
2848 | if (iter->trace && iter->trace->print_line) { |
2849 | ret = iter->trace->print_line(iter); | |
2850 | if (ret != TRACE_TYPE_UNHANDLED) | |
2851 | return ret; | |
2852 | } | |
72829bc3 | 2853 | |
09ae7234 SRRH |
2854 | if (iter->ent->type == TRACE_BPUTS && |
2855 | trace_flags & TRACE_ITER_PRINTK && | |
2856 | trace_flags & TRACE_ITER_PRINTK_MSGONLY) | |
2857 | return trace_print_bputs_msg_only(iter); | |
2858 | ||
48ead020 FW |
2859 | if (iter->ent->type == TRACE_BPRINT && |
2860 | trace_flags & TRACE_ITER_PRINTK && | |
2861 | trace_flags & TRACE_ITER_PRINTK_MSGONLY) | |
5ef841f6 | 2862 | return trace_print_bprintk_msg_only(iter); |
48ead020 | 2863 | |
66896a85 FW |
2864 | if (iter->ent->type == TRACE_PRINT && |
2865 | trace_flags & TRACE_ITER_PRINTK && | |
2866 | trace_flags & TRACE_ITER_PRINTK_MSGONLY) | |
5ef841f6 | 2867 | return trace_print_printk_msg_only(iter); |
66896a85 | 2868 | |
cb0f12aa IM |
2869 | if (trace_flags & TRACE_ITER_BIN) |
2870 | return print_bin_fmt(iter); | |
2871 | ||
5e3ca0ec IM |
2872 | if (trace_flags & TRACE_ITER_HEX) |
2873 | return print_hex_fmt(iter); | |
2874 | ||
f9896bf3 IM |
2875 | if (trace_flags & TRACE_ITER_RAW) |
2876 | return print_raw_fmt(iter); | |
2877 | ||
f9896bf3 IM |
2878 | return print_trace_fmt(iter); |
2879 | } | |
2880 | ||
7e9a49ef JO |
2881 | void trace_latency_header(struct seq_file *m) |
2882 | { | |
2883 | struct trace_iterator *iter = m->private; | |
983f938a | 2884 | struct trace_array *tr = iter->tr; |
7e9a49ef JO |
2885 | |
2886 | /* print nothing if the buffers are empty */ | |
2887 | if (trace_empty(iter)) | |
2888 | return; | |
2889 | ||
2890 | if (iter->iter_flags & TRACE_FILE_LAT_FMT) | |
2891 | print_trace_header(m, iter); | |
2892 | ||
983f938a | 2893 | if (!(tr->trace_flags & TRACE_ITER_VERBOSE)) |
7e9a49ef JO |
2894 | print_lat_help_header(m); |
2895 | } | |
2896 | ||
62b915f1 JO |
2897 | void trace_default_header(struct seq_file *m) |
2898 | { | |
2899 | struct trace_iterator *iter = m->private; | |
983f938a SRRH |
2900 | struct trace_array *tr = iter->tr; |
2901 | unsigned long trace_flags = tr->trace_flags; | |
62b915f1 | 2902 | |
f56e7f8e JO |
2903 | if (!(trace_flags & TRACE_ITER_CONTEXT_INFO)) |
2904 | return; | |
2905 | ||
62b915f1 JO |
2906 | if (iter->iter_flags & TRACE_FILE_LAT_FMT) { |
2907 | /* print nothing if the buffers are empty */ | |
2908 | if (trace_empty(iter)) | |
2909 | return; | |
2910 | print_trace_header(m, iter); | |
2911 | if (!(trace_flags & TRACE_ITER_VERBOSE)) | |
2912 | print_lat_help_header(m); | |
2913 | } else { | |
77271ce4 SR |
2914 | if (!(trace_flags & TRACE_ITER_VERBOSE)) { |
2915 | if (trace_flags & TRACE_ITER_IRQ_INFO) | |
12883efb | 2916 | print_func_help_header_irq(iter->trace_buffer, m); |
77271ce4 | 2917 | else |
12883efb | 2918 | print_func_help_header(iter->trace_buffer, m); |
77271ce4 | 2919 | } |
62b915f1 JO |
2920 | } |
2921 | } | |
2922 | ||
e0a413f6 SR |
2923 | static void test_ftrace_alive(struct seq_file *m) |
2924 | { | |
2925 | if (!ftrace_is_dead()) | |
2926 | return; | |
d79ac28f RV |
2927 | seq_puts(m, "# WARNING: FUNCTION TRACING IS CORRUPTED\n" |
2928 | "# MAY BE MISSING FUNCTION EVENTS\n"); | |
e0a413f6 SR |
2929 | } |
2930 | ||
d8741e2e | 2931 | #ifdef CONFIG_TRACER_MAX_TRACE |
f1affcaa | 2932 | static void show_snapshot_main_help(struct seq_file *m) |
d8741e2e | 2933 | { |
d79ac28f RV |
2934 | seq_puts(m, "# echo 0 > snapshot : Clears and frees snapshot buffer\n" |
2935 | "# echo 1 > snapshot : Allocates snapshot buffer, if not already allocated.\n" | |
2936 | "# Takes a snapshot of the main buffer.\n" | |
2937 | "# echo 2 > snapshot : Clears snapshot buffer (but does not allocate or free)\n" | |
2938 | "# (Doesn't have to be '2' works with any number that\n" | |
2939 | "# is not a '0' or '1')\n"); | |
d8741e2e | 2940 | } |
f1affcaa SRRH |
2941 | |
2942 | static void show_snapshot_percpu_help(struct seq_file *m) | |
2943 | { | |
fa6f0cc7 | 2944 | seq_puts(m, "# echo 0 > snapshot : Invalid for per_cpu snapshot file.\n"); |
f1affcaa | 2945 | #ifdef CONFIG_RING_BUFFER_ALLOW_SWAP |
d79ac28f RV |
2946 | seq_puts(m, "# echo 1 > snapshot : Allocates snapshot buffer, if not already allocated.\n" |
2947 | "# Takes a snapshot of the main buffer for this cpu.\n"); | |
f1affcaa | 2948 | #else |
d79ac28f RV |
2949 | seq_puts(m, "# echo 1 > snapshot : Not supported with this kernel.\n" |
2950 | "# Must use main snapshot file to allocate.\n"); | |
f1affcaa | 2951 | #endif |
d79ac28f RV |
2952 | seq_puts(m, "# echo 2 > snapshot : Clears this cpu's snapshot buffer (but does not allocate)\n" |
2953 | "# (Doesn't have to be '2' works with any number that\n" | |
2954 | "# is not a '0' or '1')\n"); | |
f1affcaa SRRH |
2955 | } |
2956 | ||
d8741e2e SRRH |
2957 | static void print_snapshot_help(struct seq_file *m, struct trace_iterator *iter) |
2958 | { | |
45ad21ca | 2959 | if (iter->tr->allocated_snapshot) |
fa6f0cc7 | 2960 | seq_puts(m, "#\n# * Snapshot is allocated *\n#\n"); |
d8741e2e | 2961 | else |
fa6f0cc7 | 2962 | seq_puts(m, "#\n# * Snapshot is freed *\n#\n"); |
d8741e2e | 2963 | |
fa6f0cc7 | 2964 | seq_puts(m, "# Snapshot commands:\n"); |
f1affcaa SRRH |
2965 | if (iter->cpu_file == RING_BUFFER_ALL_CPUS) |
2966 | show_snapshot_main_help(m); | |
2967 | else | |
2968 | show_snapshot_percpu_help(m); | |
d8741e2e SRRH |
2969 | } |
2970 | #else | |
2971 | /* Should never be called */ | |
2972 | static inline void print_snapshot_help(struct seq_file *m, struct trace_iterator *iter) { } | |
2973 | #endif | |
2974 | ||
bc0c38d1 SR |
2975 | static int s_show(struct seq_file *m, void *v) |
2976 | { | |
2977 | struct trace_iterator *iter = v; | |
a63ce5b3 | 2978 | int ret; |
bc0c38d1 SR |
2979 | |
2980 | if (iter->ent == NULL) { | |
2981 | if (iter->tr) { | |
2982 | seq_printf(m, "# tracer: %s\n", iter->trace->name); | |
2983 | seq_puts(m, "#\n"); | |
e0a413f6 | 2984 | test_ftrace_alive(m); |
bc0c38d1 | 2985 | } |
d8741e2e SRRH |
2986 | if (iter->snapshot && trace_empty(iter)) |
2987 | print_snapshot_help(m, iter); | |
2988 | else if (iter->trace && iter->trace->print_header) | |
8bba1bf5 | 2989 | iter->trace->print_header(m); |
62b915f1 JO |
2990 | else |
2991 | trace_default_header(m); | |
2992 | ||
a63ce5b3 SR |
2993 | } else if (iter->leftover) { |
2994 | /* | |
2995 | * If we filled the seq_file buffer earlier, we | |
2996 | * want to just show it now. | |
2997 | */ | |
2998 | ret = trace_print_seq(m, &iter->seq); | |
2999 | ||
3000 | /* ret should this time be zero, but you never know */ | |
3001 | iter->leftover = ret; | |
3002 | ||
bc0c38d1 | 3003 | } else { |
f9896bf3 | 3004 | print_trace_line(iter); |
a63ce5b3 SR |
3005 | ret = trace_print_seq(m, &iter->seq); |
3006 | /* | |
3007 | * If we overflow the seq_file buffer, then it will | |
3008 | * ask us for this data again at start up. | |
3009 | * Use that instead. | |
3010 | * ret is 0 if seq_file write succeeded. | |
3011 | * -1 otherwise. | |
3012 | */ | |
3013 | iter->leftover = ret; | |
bc0c38d1 SR |
3014 | } |
3015 | ||
3016 | return 0; | |
3017 | } | |
3018 | ||
649e9c70 ON |
3019 | /* |
3020 | * Should be used after trace_array_get(), trace_types_lock | |
3021 | * ensures that i_cdev was already initialized. | |
3022 | */ | |
3023 | static inline int tracing_get_cpu(struct inode *inode) | |
3024 | { | |
3025 | if (inode->i_cdev) /* See trace_create_cpu_file() */ | |
3026 | return (long)inode->i_cdev - 1; | |
3027 | return RING_BUFFER_ALL_CPUS; | |
3028 | } | |
3029 | ||
88e9d34c | 3030 | static const struct seq_operations tracer_seq_ops = { |
4bf39a94 IM |
3031 | .start = s_start, |
3032 | .next = s_next, | |
3033 | .stop = s_stop, | |
3034 | .show = s_show, | |
bc0c38d1 SR |
3035 | }; |
3036 | ||
e309b41d | 3037 | static struct trace_iterator * |
6484c71c | 3038 | __tracing_open(struct inode *inode, struct file *file, bool snapshot) |
bc0c38d1 | 3039 | { |
6484c71c | 3040 | struct trace_array *tr = inode->i_private; |
bc0c38d1 | 3041 | struct trace_iterator *iter; |
50e18b94 | 3042 | int cpu; |
bc0c38d1 | 3043 | |
85a2f9b4 SR |
3044 | if (tracing_disabled) |
3045 | return ERR_PTR(-ENODEV); | |
60a11774 | 3046 | |
50e18b94 | 3047 | iter = __seq_open_private(file, &tracer_seq_ops, sizeof(*iter)); |
85a2f9b4 SR |
3048 | if (!iter) |
3049 | return ERR_PTR(-ENOMEM); | |
bc0c38d1 | 3050 | |
72917235 | 3051 | iter->buffer_iter = kcalloc(nr_cpu_ids, sizeof(*iter->buffer_iter), |
6d158a81 | 3052 | GFP_KERNEL); |
93574fcc DC |
3053 | if (!iter->buffer_iter) |
3054 | goto release; | |
3055 | ||
d7350c3f FW |
3056 | /* |
3057 | * We make a copy of the current tracer to avoid concurrent | |
3058 | * changes on it while we are reading. | |
3059 | */ | |
bc0c38d1 | 3060 | mutex_lock(&trace_types_lock); |
d7350c3f | 3061 | iter->trace = kzalloc(sizeof(*iter->trace), GFP_KERNEL); |
85a2f9b4 | 3062 | if (!iter->trace) |
d7350c3f | 3063 | goto fail; |
85a2f9b4 | 3064 | |
2b6080f2 | 3065 | *iter->trace = *tr->current_trace; |
d7350c3f | 3066 | |
79f55997 | 3067 | if (!zalloc_cpumask_var(&iter->started, GFP_KERNEL)) |
b0dfa978 FW |
3068 | goto fail; |
3069 | ||
12883efb SRRH |
3070 | iter->tr = tr; |
3071 | ||
3072 | #ifdef CONFIG_TRACER_MAX_TRACE | |
2b6080f2 SR |
3073 | /* Currently only the top directory has a snapshot */ |
3074 | if (tr->current_trace->print_max || snapshot) | |
12883efb | 3075 | iter->trace_buffer = &tr->max_buffer; |
bc0c38d1 | 3076 | else |
12883efb SRRH |
3077 | #endif |
3078 | iter->trace_buffer = &tr->trace_buffer; | |
debdd57f | 3079 | iter->snapshot = snapshot; |
bc0c38d1 | 3080 | iter->pos = -1; |
6484c71c | 3081 | iter->cpu_file = tracing_get_cpu(inode); |
d7350c3f | 3082 | mutex_init(&iter->mutex); |
bc0c38d1 | 3083 | |
8bba1bf5 MM |
3084 | /* Notify the tracer early; before we stop tracing. */ |
3085 | if (iter->trace && iter->trace->open) | |
a93751ca | 3086 | iter->trace->open(iter); |
8bba1bf5 | 3087 | |
12ef7d44 | 3088 | /* Annotate start of buffers if we had overruns */ |
12883efb | 3089 | if (ring_buffer_overruns(iter->trace_buffer->buffer)) |
12ef7d44 SR |
3090 | iter->iter_flags |= TRACE_FILE_ANNOTATE; |
3091 | ||
8be0709f | 3092 | /* Output in nanoseconds only if we are using a clock in nanoseconds. */ |
58e8eedf | 3093 | if (trace_clocks[tr->clock_id].in_ns) |
8be0709f DS |
3094 | iter->iter_flags |= TRACE_FILE_TIME_IN_NS; |
3095 | ||
debdd57f HT |
3096 | /* stop the trace while dumping if we are not opening "snapshot" */ |
3097 | if (!iter->snapshot) | |
2b6080f2 | 3098 | tracing_stop_tr(tr); |
2f26ebd5 | 3099 | |
ae3b5093 | 3100 | if (iter->cpu_file == RING_BUFFER_ALL_CPUS) { |
b04cc6b1 | 3101 | for_each_tracing_cpu(cpu) { |
b04cc6b1 | 3102 | iter->buffer_iter[cpu] = |
12883efb | 3103 | ring_buffer_read_prepare(iter->trace_buffer->buffer, cpu); |
72c9ddfd DM |
3104 | } |
3105 | ring_buffer_read_prepare_sync(); | |
3106 | for_each_tracing_cpu(cpu) { | |
3107 | ring_buffer_read_start(iter->buffer_iter[cpu]); | |
2f26ebd5 | 3108 | tracing_iter_reset(iter, cpu); |
b04cc6b1 FW |
3109 | } |
3110 | } else { | |
3111 | cpu = iter->cpu_file; | |
3928a8a2 | 3112 | iter->buffer_iter[cpu] = |
12883efb | 3113 | ring_buffer_read_prepare(iter->trace_buffer->buffer, cpu); |
72c9ddfd DM |
3114 | ring_buffer_read_prepare_sync(); |
3115 | ring_buffer_read_start(iter->buffer_iter[cpu]); | |
2f26ebd5 | 3116 | tracing_iter_reset(iter, cpu); |
3928a8a2 SR |
3117 | } |
3118 | ||
bc0c38d1 SR |
3119 | mutex_unlock(&trace_types_lock); |
3120 | ||
bc0c38d1 | 3121 | return iter; |
3928a8a2 | 3122 | |
d7350c3f | 3123 | fail: |
3928a8a2 | 3124 | mutex_unlock(&trace_types_lock); |
d7350c3f | 3125 | kfree(iter->trace); |
6d158a81 | 3126 | kfree(iter->buffer_iter); |
93574fcc | 3127 | release: |
50e18b94 JO |
3128 | seq_release_private(inode, file); |
3129 | return ERR_PTR(-ENOMEM); | |
bc0c38d1 SR |
3130 | } |
3131 | ||
3132 | int tracing_open_generic(struct inode *inode, struct file *filp) | |
3133 | { | |
60a11774 SR |
3134 | if (tracing_disabled) |
3135 | return -ENODEV; | |
3136 | ||
bc0c38d1 SR |
3137 | filp->private_data = inode->i_private; |
3138 | return 0; | |
3139 | } | |
3140 | ||
2e86421d GB |
3141 | bool tracing_is_disabled(void) |
3142 | { | |
3143 | return (tracing_disabled) ? true: false; | |
3144 | } | |
3145 | ||
7b85af63 SRRH |
3146 | /* |
3147 | * Open and update trace_array ref count. | |
3148 | * Must have the current trace_array passed to it. | |
3149 | */ | |
dcc30223 | 3150 | static int tracing_open_generic_tr(struct inode *inode, struct file *filp) |
7b85af63 SRRH |
3151 | { |
3152 | struct trace_array *tr = inode->i_private; | |
3153 | ||
3154 | if (tracing_disabled) | |
3155 | return -ENODEV; | |
3156 | ||
3157 | if (trace_array_get(tr) < 0) | |
3158 | return -ENODEV; | |
3159 | ||
3160 | filp->private_data = inode->i_private; | |
3161 | ||
3162 | return 0; | |
7b85af63 SRRH |
3163 | } |
3164 | ||
4fd27358 | 3165 | static int tracing_release(struct inode *inode, struct file *file) |
bc0c38d1 | 3166 | { |
6484c71c | 3167 | struct trace_array *tr = inode->i_private; |
907f2784 | 3168 | struct seq_file *m = file->private_data; |
4acd4d00 | 3169 | struct trace_iterator *iter; |
3928a8a2 | 3170 | int cpu; |
bc0c38d1 | 3171 | |
ff451961 | 3172 | if (!(file->f_mode & FMODE_READ)) { |
6484c71c | 3173 | trace_array_put(tr); |
4acd4d00 | 3174 | return 0; |
ff451961 | 3175 | } |
4acd4d00 | 3176 | |
6484c71c | 3177 | /* Writes do not use seq_file */ |
4acd4d00 | 3178 | iter = m->private; |
bc0c38d1 | 3179 | mutex_lock(&trace_types_lock); |
a695cb58 | 3180 | |
3928a8a2 SR |
3181 | for_each_tracing_cpu(cpu) { |
3182 | if (iter->buffer_iter[cpu]) | |
3183 | ring_buffer_read_finish(iter->buffer_iter[cpu]); | |
3184 | } | |
3185 | ||
bc0c38d1 SR |
3186 | if (iter->trace && iter->trace->close) |
3187 | iter->trace->close(iter); | |
3188 | ||
debdd57f HT |
3189 | if (!iter->snapshot) |
3190 | /* reenable tracing if it was previously enabled */ | |
2b6080f2 | 3191 | tracing_start_tr(tr); |
f77d09a3 AL |
3192 | |
3193 | __trace_array_put(tr); | |
3194 | ||
bc0c38d1 SR |
3195 | mutex_unlock(&trace_types_lock); |
3196 | ||
d7350c3f | 3197 | mutex_destroy(&iter->mutex); |
b0dfa978 | 3198 | free_cpumask_var(iter->started); |
d7350c3f | 3199 | kfree(iter->trace); |
6d158a81 | 3200 | kfree(iter->buffer_iter); |
50e18b94 | 3201 | seq_release_private(inode, file); |
ff451961 | 3202 | |
bc0c38d1 SR |
3203 | return 0; |
3204 | } | |
3205 | ||
7b85af63 SRRH |
3206 | static int tracing_release_generic_tr(struct inode *inode, struct file *file) |
3207 | { | |
3208 | struct trace_array *tr = inode->i_private; | |
3209 | ||
3210 | trace_array_put(tr); | |
bc0c38d1 SR |
3211 | return 0; |
3212 | } | |
3213 | ||
7b85af63 SRRH |
3214 | static int tracing_single_release_tr(struct inode *inode, struct file *file) |
3215 | { | |
3216 | struct trace_array *tr = inode->i_private; | |
3217 | ||
3218 | trace_array_put(tr); | |
3219 | ||
3220 | return single_release(inode, file); | |
3221 | } | |
3222 | ||
bc0c38d1 SR |
3223 | static int tracing_open(struct inode *inode, struct file *file) |
3224 | { | |
6484c71c | 3225 | struct trace_array *tr = inode->i_private; |
85a2f9b4 SR |
3226 | struct trace_iterator *iter; |
3227 | int ret = 0; | |
bc0c38d1 | 3228 | |
ff451961 SRRH |
3229 | if (trace_array_get(tr) < 0) |
3230 | return -ENODEV; | |
3231 | ||
4acd4d00 | 3232 | /* If this file was open for write, then erase contents */ |
6484c71c ON |
3233 | if ((file->f_mode & FMODE_WRITE) && (file->f_flags & O_TRUNC)) { |
3234 | int cpu = tracing_get_cpu(inode); | |
3235 | ||
3236 | if (cpu == RING_BUFFER_ALL_CPUS) | |
12883efb | 3237 | tracing_reset_online_cpus(&tr->trace_buffer); |
4acd4d00 | 3238 | else |
6484c71c | 3239 | tracing_reset(&tr->trace_buffer, cpu); |
4acd4d00 | 3240 | } |
bc0c38d1 | 3241 | |
4acd4d00 | 3242 | if (file->f_mode & FMODE_READ) { |
6484c71c | 3243 | iter = __tracing_open(inode, file, false); |
4acd4d00 SR |
3244 | if (IS_ERR(iter)) |
3245 | ret = PTR_ERR(iter); | |
983f938a | 3246 | else if (tr->trace_flags & TRACE_ITER_LATENCY_FMT) |
4acd4d00 SR |
3247 | iter->iter_flags |= TRACE_FILE_LAT_FMT; |
3248 | } | |
ff451961 SRRH |
3249 | |
3250 | if (ret < 0) | |
3251 | trace_array_put(tr); | |
3252 | ||
bc0c38d1 SR |
3253 | return ret; |
3254 | } | |
3255 | ||
607e2ea1 SRRH |
3256 | /* |
3257 | * Some tracers are not suitable for instance buffers. | |
3258 | * A tracer is always available for the global array (toplevel) | |
3259 | * or if it explicitly states that it is. | |
3260 | */ | |
3261 | static bool | |
3262 | trace_ok_for_array(struct tracer *t, struct trace_array *tr) | |
3263 | { | |
3264 | return (tr->flags & TRACE_ARRAY_FL_GLOBAL) || t->allow_instances; | |
3265 | } | |
3266 | ||
3267 | /* Find the next tracer that this trace array may use */ | |
3268 | static struct tracer * | |
3269 | get_tracer_for_array(struct trace_array *tr, struct tracer *t) | |
3270 | { | |
3271 | while (t && !trace_ok_for_array(t, tr)) | |
3272 | t = t->next; | |
3273 | ||
3274 | return t; | |
3275 | } | |
3276 | ||
e309b41d | 3277 | static void * |
bc0c38d1 SR |
3278 | t_next(struct seq_file *m, void *v, loff_t *pos) |
3279 | { | |
607e2ea1 | 3280 | struct trace_array *tr = m->private; |
f129e965 | 3281 | struct tracer *t = v; |
bc0c38d1 SR |
3282 | |
3283 | (*pos)++; | |
3284 | ||
3285 | if (t) | |
607e2ea1 | 3286 | t = get_tracer_for_array(tr, t->next); |
bc0c38d1 | 3287 | |
bc0c38d1 SR |
3288 | return t; |
3289 | } | |
3290 | ||
3291 | static void *t_start(struct seq_file *m, loff_t *pos) | |
3292 | { | |
607e2ea1 | 3293 | struct trace_array *tr = m->private; |
f129e965 | 3294 | struct tracer *t; |
bc0c38d1 SR |
3295 | loff_t l = 0; |
3296 | ||
3297 | mutex_lock(&trace_types_lock); | |
607e2ea1 SRRH |
3298 | |
3299 | t = get_tracer_for_array(tr, trace_types); | |
3300 | for (; t && l < *pos; t = t_next(m, t, &l)) | |
3301 | ; | |
bc0c38d1 SR |
3302 | |
3303 | return t; | |
3304 | } | |
3305 | ||
3306 | static void t_stop(struct seq_file *m, void *p) | |
3307 | { | |
3308 | mutex_unlock(&trace_types_lock); | |
3309 | } | |
3310 | ||
3311 | static int t_show(struct seq_file *m, void *v) | |
3312 | { | |
3313 | struct tracer *t = v; | |
3314 | ||
3315 | if (!t) | |
3316 | return 0; | |
3317 | ||
fa6f0cc7 | 3318 | seq_puts(m, t->name); |
bc0c38d1 SR |
3319 | if (t->next) |
3320 | seq_putc(m, ' '); | |
3321 | else | |
3322 | seq_putc(m, '\n'); | |
3323 | ||
3324 | return 0; | |
3325 | } | |
3326 | ||
88e9d34c | 3327 | static const struct seq_operations show_traces_seq_ops = { |
4bf39a94 IM |
3328 | .start = t_start, |
3329 | .next = t_next, | |
3330 | .stop = t_stop, | |
3331 | .show = t_show, | |
bc0c38d1 SR |
3332 | }; |
3333 | ||
3334 | static int show_traces_open(struct inode *inode, struct file *file) | |
3335 | { | |
607e2ea1 SRRH |
3336 | struct trace_array *tr = inode->i_private; |
3337 | struct seq_file *m; | |
3338 | int ret; | |
3339 | ||
60a11774 SR |
3340 | if (tracing_disabled) |
3341 | return -ENODEV; | |
3342 | ||
607e2ea1 SRRH |
3343 | ret = seq_open(file, &show_traces_seq_ops); |
3344 | if (ret) | |
3345 | return ret; | |
3346 | ||
3347 | m = file->private_data; | |
3348 | m->private = tr; | |
3349 | ||
3350 | return 0; | |
bc0c38d1 SR |
3351 | } |
3352 | ||
4acd4d00 SR |
3353 | static ssize_t |
3354 | tracing_write_stub(struct file *filp, const char __user *ubuf, | |
3355 | size_t count, loff_t *ppos) | |
3356 | { | |
3357 | return count; | |
3358 | } | |
3359 | ||
098c879e | 3360 | loff_t tracing_lseek(struct file *file, loff_t offset, int whence) |
364829b1 | 3361 | { |
098c879e SRRH |
3362 | int ret; |
3363 | ||
364829b1 | 3364 | if (file->f_mode & FMODE_READ) |
098c879e | 3365 | ret = seq_lseek(file, offset, whence); |
364829b1 | 3366 | else |
098c879e SRRH |
3367 | file->f_pos = ret = 0; |
3368 | ||
3369 | return ret; | |
364829b1 SP |
3370 | } |
3371 | ||
5e2336a0 | 3372 | static const struct file_operations tracing_fops = { |
4bf39a94 IM |
3373 | .open = tracing_open, |
3374 | .read = seq_read, | |
4acd4d00 | 3375 | .write = tracing_write_stub, |
098c879e | 3376 | .llseek = tracing_lseek, |
4bf39a94 | 3377 | .release = tracing_release, |
bc0c38d1 SR |
3378 | }; |
3379 | ||
5e2336a0 | 3380 | static const struct file_operations show_traces_fops = { |
c7078de1 IM |
3381 | .open = show_traces_open, |
3382 | .read = seq_read, | |
3383 | .release = seq_release, | |
b444786f | 3384 | .llseek = seq_lseek, |
c7078de1 IM |
3385 | }; |
3386 | ||
36dfe925 IM |
3387 | /* |
3388 | * The tracer itself will not take this lock, but still we want | |
3389 | * to provide a consistent cpumask to user-space: | |
3390 | */ | |
3391 | static DEFINE_MUTEX(tracing_cpumask_update_lock); | |
3392 | ||
3393 | /* | |
3394 | * Temporary storage for the character representation of the | |
3395 | * CPU bitmask (and one more byte for the newline): | |
3396 | */ | |
3397 | static char mask_str[NR_CPUS + 1]; | |
3398 | ||
c7078de1 IM |
3399 | static ssize_t |
3400 | tracing_cpumask_read(struct file *filp, char __user *ubuf, | |
3401 | size_t count, loff_t *ppos) | |
3402 | { | |
ccfe9e42 | 3403 | struct trace_array *tr = file_inode(filp)->i_private; |
36dfe925 | 3404 | int len; |
c7078de1 IM |
3405 | |
3406 | mutex_lock(&tracing_cpumask_update_lock); | |
36dfe925 | 3407 | |
1a40243b TH |
3408 | len = snprintf(mask_str, count, "%*pb\n", |
3409 | cpumask_pr_args(tr->tracing_cpumask)); | |
3410 | if (len >= count) { | |
36dfe925 IM |
3411 | count = -EINVAL; |
3412 | goto out_err; | |
3413 | } | |
36dfe925 IM |
3414 | count = simple_read_from_buffer(ubuf, count, ppos, mask_str, NR_CPUS+1); |
3415 | ||
3416 | out_err: | |
c7078de1 IM |
3417 | mutex_unlock(&tracing_cpumask_update_lock); |
3418 | ||
3419 | return count; | |
3420 | } | |
3421 | ||
3422 | static ssize_t | |
3423 | tracing_cpumask_write(struct file *filp, const char __user *ubuf, | |
3424 | size_t count, loff_t *ppos) | |
3425 | { | |
ccfe9e42 | 3426 | struct trace_array *tr = file_inode(filp)->i_private; |
9e01c1b7 | 3427 | cpumask_var_t tracing_cpumask_new; |
2b6080f2 | 3428 | int err, cpu; |
9e01c1b7 RR |
3429 | |
3430 | if (!alloc_cpumask_var(&tracing_cpumask_new, GFP_KERNEL)) | |
3431 | return -ENOMEM; | |
c7078de1 | 3432 | |
9e01c1b7 | 3433 | err = cpumask_parse_user(ubuf, count, tracing_cpumask_new); |
c7078de1 | 3434 | if (err) |
36dfe925 IM |
3435 | goto err_unlock; |
3436 | ||
215368e8 LZ |
3437 | mutex_lock(&tracing_cpumask_update_lock); |
3438 | ||
a5e25883 | 3439 | local_irq_disable(); |
0b9b12c1 | 3440 | arch_spin_lock(&tr->max_lock); |
ab46428c | 3441 | for_each_tracing_cpu(cpu) { |
36dfe925 IM |
3442 | /* |
3443 | * Increase/decrease the disabled counter if we are | |
3444 | * about to flip a bit in the cpumask: | |
3445 | */ | |
ccfe9e42 | 3446 | if (cpumask_test_cpu(cpu, tr->tracing_cpumask) && |
9e01c1b7 | 3447 | !cpumask_test_cpu(cpu, tracing_cpumask_new)) { |
12883efb SRRH |
3448 | atomic_inc(&per_cpu_ptr(tr->trace_buffer.data, cpu)->disabled); |
3449 | ring_buffer_record_disable_cpu(tr->trace_buffer.buffer, cpu); | |
36dfe925 | 3450 | } |
ccfe9e42 | 3451 | if (!cpumask_test_cpu(cpu, tr->tracing_cpumask) && |
9e01c1b7 | 3452 | cpumask_test_cpu(cpu, tracing_cpumask_new)) { |
12883efb SRRH |
3453 | atomic_dec(&per_cpu_ptr(tr->trace_buffer.data, cpu)->disabled); |
3454 | ring_buffer_record_enable_cpu(tr->trace_buffer.buffer, cpu); | |
36dfe925 IM |
3455 | } |
3456 | } | |
0b9b12c1 | 3457 | arch_spin_unlock(&tr->max_lock); |
a5e25883 | 3458 | local_irq_enable(); |
36dfe925 | 3459 | |
ccfe9e42 | 3460 | cpumask_copy(tr->tracing_cpumask, tracing_cpumask_new); |
36dfe925 IM |
3461 | |
3462 | mutex_unlock(&tracing_cpumask_update_lock); | |
9e01c1b7 | 3463 | free_cpumask_var(tracing_cpumask_new); |
c7078de1 IM |
3464 | |
3465 | return count; | |
36dfe925 IM |
3466 | |
3467 | err_unlock: | |
215368e8 | 3468 | free_cpumask_var(tracing_cpumask_new); |
36dfe925 IM |
3469 | |
3470 | return err; | |
c7078de1 IM |
3471 | } |
3472 | ||
5e2336a0 | 3473 | static const struct file_operations tracing_cpumask_fops = { |
ccfe9e42 | 3474 | .open = tracing_open_generic_tr, |
c7078de1 IM |
3475 | .read = tracing_cpumask_read, |
3476 | .write = tracing_cpumask_write, | |
ccfe9e42 | 3477 | .release = tracing_release_generic_tr, |
b444786f | 3478 | .llseek = generic_file_llseek, |
bc0c38d1 SR |
3479 | }; |
3480 | ||
fdb372ed | 3481 | static int tracing_trace_options_show(struct seq_file *m, void *v) |
bc0c38d1 | 3482 | { |
d8e83d26 | 3483 | struct tracer_opt *trace_opts; |
2b6080f2 | 3484 | struct trace_array *tr = m->private; |
d8e83d26 | 3485 | u32 tracer_flags; |
d8e83d26 | 3486 | int i; |
adf9f195 | 3487 | |
d8e83d26 | 3488 | mutex_lock(&trace_types_lock); |
2b6080f2 SR |
3489 | tracer_flags = tr->current_trace->flags->val; |
3490 | trace_opts = tr->current_trace->flags->opts; | |
d8e83d26 | 3491 | |
bc0c38d1 | 3492 | for (i = 0; trace_options[i]; i++) { |
983f938a | 3493 | if (tr->trace_flags & (1 << i)) |
fdb372ed | 3494 | seq_printf(m, "%s\n", trace_options[i]); |
bc0c38d1 | 3495 | else |
fdb372ed | 3496 | seq_printf(m, "no%s\n", trace_options[i]); |
bc0c38d1 SR |
3497 | } |
3498 | ||
adf9f195 FW |
3499 | for (i = 0; trace_opts[i].name; i++) { |
3500 | if (tracer_flags & trace_opts[i].bit) | |
fdb372ed | 3501 | seq_printf(m, "%s\n", trace_opts[i].name); |
adf9f195 | 3502 | else |
fdb372ed | 3503 | seq_printf(m, "no%s\n", trace_opts[i].name); |
adf9f195 | 3504 | } |
d8e83d26 | 3505 | mutex_unlock(&trace_types_lock); |
adf9f195 | 3506 | |
fdb372ed | 3507 | return 0; |
bc0c38d1 | 3508 | } |
bc0c38d1 | 3509 | |
8c1a49ae | 3510 | static int __set_tracer_option(struct trace_array *tr, |
8d18eaaf LZ |
3511 | struct tracer_flags *tracer_flags, |
3512 | struct tracer_opt *opts, int neg) | |
3513 | { | |
8c1a49ae | 3514 | struct tracer *trace = tr->current_trace; |
8d18eaaf | 3515 | int ret; |
bc0c38d1 | 3516 | |
8c1a49ae | 3517 | ret = trace->set_flag(tr, tracer_flags->val, opts->bit, !neg); |
8d18eaaf LZ |
3518 | if (ret) |
3519 | return ret; | |
3520 | ||
3521 | if (neg) | |
3522 | tracer_flags->val &= ~opts->bit; | |
3523 | else | |
3524 | tracer_flags->val |= opts->bit; | |
3525 | return 0; | |
bc0c38d1 SR |
3526 | } |
3527 | ||
adf9f195 | 3528 | /* Try to assign a tracer specific option */ |
8c1a49ae | 3529 | static int set_tracer_option(struct trace_array *tr, char *cmp, int neg) |
adf9f195 | 3530 | { |
8c1a49ae | 3531 | struct tracer *trace = tr->current_trace; |
7770841e | 3532 | struct tracer_flags *tracer_flags = trace->flags; |
adf9f195 | 3533 | struct tracer_opt *opts = NULL; |
8d18eaaf | 3534 | int i; |
adf9f195 | 3535 | |
7770841e Z |
3536 | for (i = 0; tracer_flags->opts[i].name; i++) { |
3537 | opts = &tracer_flags->opts[i]; | |
adf9f195 | 3538 | |
8d18eaaf | 3539 | if (strcmp(cmp, opts->name) == 0) |
8c1a49ae | 3540 | return __set_tracer_option(tr, trace->flags, opts, neg); |
adf9f195 | 3541 | } |
adf9f195 | 3542 | |
8d18eaaf | 3543 | return -EINVAL; |
adf9f195 FW |
3544 | } |
3545 | ||
613f04a0 SRRH |
3546 | /* Some tracers require overwrite to stay enabled */ |
3547 | int trace_keep_overwrite(struct tracer *tracer, u32 mask, int set) | |
3548 | { | |
3549 | if (tracer->enabled && (mask & TRACE_ITER_OVERWRITE) && !set) | |
3550 | return -1; | |
3551 | ||
3552 | return 0; | |
3553 | } | |
3554 | ||
2b6080f2 | 3555 | int set_tracer_flag(struct trace_array *tr, unsigned int mask, int enabled) |
af4617bd SR |
3556 | { |
3557 | /* do nothing if flag is already set */ | |
983f938a | 3558 | if (!!(tr->trace_flags & mask) == !!enabled) |
613f04a0 SRRH |
3559 | return 0; |
3560 | ||
3561 | /* Give the tracer a chance to approve the change */ | |
2b6080f2 | 3562 | if (tr->current_trace->flag_changed) |
bf6065b5 | 3563 | if (tr->current_trace->flag_changed(tr, mask, !!enabled)) |
613f04a0 | 3564 | return -EINVAL; |
af4617bd SR |
3565 | |
3566 | if (enabled) | |
983f938a | 3567 | tr->trace_flags |= mask; |
af4617bd | 3568 | else |
983f938a | 3569 | tr->trace_flags &= ~mask; |
e870e9a1 LZ |
3570 | |
3571 | if (mask == TRACE_ITER_RECORD_CMD) | |
3572 | trace_event_enable_cmd_record(enabled); | |
750912fa | 3573 | |
80902822 | 3574 | if (mask == TRACE_ITER_OVERWRITE) { |
12883efb | 3575 | ring_buffer_change_overwrite(tr->trace_buffer.buffer, enabled); |
80902822 | 3576 | #ifdef CONFIG_TRACER_MAX_TRACE |
12883efb | 3577 | ring_buffer_change_overwrite(tr->max_buffer.buffer, enabled); |
80902822 SRRH |
3578 | #endif |
3579 | } | |
81698831 | 3580 | |
b9f9108c | 3581 | if (mask == TRACE_ITER_PRINTK) { |
81698831 | 3582 | trace_printk_start_stop_comm(enabled); |
b9f9108c SRRH |
3583 | trace_printk_control(enabled); |
3584 | } | |
613f04a0 SRRH |
3585 | |
3586 | return 0; | |
af4617bd SR |
3587 | } |
3588 | ||
2b6080f2 | 3589 | static int trace_set_options(struct trace_array *tr, char *option) |
bc0c38d1 | 3590 | { |
8d18eaaf | 3591 | char *cmp; |
bc0c38d1 | 3592 | int neg = 0; |
613f04a0 | 3593 | int ret = -ENODEV; |
bc0c38d1 | 3594 | int i; |
a4d1e688 | 3595 | size_t orig_len = strlen(option); |
bc0c38d1 | 3596 | |
7bcfaf54 | 3597 | cmp = strstrip(option); |
bc0c38d1 | 3598 | |
8d18eaaf | 3599 | if (strncmp(cmp, "no", 2) == 0) { |
bc0c38d1 SR |
3600 | neg = 1; |
3601 | cmp += 2; | |
3602 | } | |
3603 | ||
69d34da2 SRRH |
3604 | mutex_lock(&trace_types_lock); |
3605 | ||
bc0c38d1 | 3606 | for (i = 0; trace_options[i]; i++) { |
8d18eaaf | 3607 | if (strcmp(cmp, trace_options[i]) == 0) { |
2b6080f2 | 3608 | ret = set_tracer_flag(tr, 1 << i, !neg); |
bc0c38d1 SR |
3609 | break; |
3610 | } | |
3611 | } | |
adf9f195 FW |
3612 | |
3613 | /* If no option could be set, test the specific tracer options */ | |
69d34da2 | 3614 | if (!trace_options[i]) |
8c1a49ae | 3615 | ret = set_tracer_option(tr, cmp, neg); |
69d34da2 SRRH |
3616 | |
3617 | mutex_unlock(&trace_types_lock); | |
bc0c38d1 | 3618 | |
a4d1e688 JW |
3619 | /* |
3620 | * If the first trailing whitespace is replaced with '\0' by strstrip, | |
3621 | * turn it back into a space. | |
3622 | */ | |
3623 | if (orig_len > strlen(option)) | |
3624 | option[strlen(option)] = ' '; | |
3625 | ||
7bcfaf54 SR |
3626 | return ret; |
3627 | } | |
3628 | ||
a4d1e688 JW |
3629 | static void __init apply_trace_boot_options(void) |
3630 | { | |
3631 | char *buf = trace_boot_options_buf; | |
3632 | char *option; | |
3633 | ||
3634 | while (true) { | |
3635 | option = strsep(&buf, ","); | |
3636 | ||
3637 | if (!option) | |
3638 | break; | |
3639 | if (!*option) | |
3640 | continue; | |
3641 | ||
3642 | trace_set_options(&global_trace, option); | |
3643 | ||
3644 | /* Put back the comma to allow this to be called again */ | |
3645 | if (buf) | |
3646 | *(buf - 1) = ','; | |
3647 | } | |
3648 | } | |
3649 | ||
7bcfaf54 SR |
3650 | static ssize_t |
3651 | tracing_trace_options_write(struct file *filp, const char __user *ubuf, | |
3652 | size_t cnt, loff_t *ppos) | |
3653 | { | |
2b6080f2 SR |
3654 | struct seq_file *m = filp->private_data; |
3655 | struct trace_array *tr = m->private; | |
7bcfaf54 | 3656 | char buf[64]; |
613f04a0 | 3657 | int ret; |
7bcfaf54 SR |
3658 | |
3659 | if (cnt >= sizeof(buf)) | |
3660 | return -EINVAL; | |
3661 | ||
3662 | if (copy_from_user(&buf, ubuf, cnt)) | |
3663 | return -EFAULT; | |
3664 | ||
a8dd2176 SR |
3665 | buf[cnt] = 0; |
3666 | ||
2b6080f2 | 3667 | ret = trace_set_options(tr, buf); |
613f04a0 SRRH |
3668 | if (ret < 0) |
3669 | return ret; | |
7bcfaf54 | 3670 | |
cf8517cf | 3671 | *ppos += cnt; |
bc0c38d1 SR |
3672 | |
3673 | return cnt; | |
3674 | } | |
3675 | ||
fdb372ed LZ |
3676 | static int tracing_trace_options_open(struct inode *inode, struct file *file) |
3677 | { | |
7b85af63 | 3678 | struct trace_array *tr = inode->i_private; |
f77d09a3 | 3679 | int ret; |
7b85af63 | 3680 | |
fdb372ed LZ |
3681 | if (tracing_disabled) |
3682 | return -ENODEV; | |
2b6080f2 | 3683 | |
7b85af63 SRRH |
3684 | if (trace_array_get(tr) < 0) |
3685 | return -ENODEV; | |
3686 | ||
f77d09a3 AL |
3687 | ret = single_open(file, tracing_trace_options_show, inode->i_private); |
3688 | if (ret < 0) | |
3689 | trace_array_put(tr); | |
3690 | ||
3691 | return ret; | |
fdb372ed LZ |
3692 | } |
3693 | ||
5e2336a0 | 3694 | static const struct file_operations tracing_iter_fops = { |
fdb372ed LZ |
3695 | .open = tracing_trace_options_open, |
3696 | .read = seq_read, | |
3697 | .llseek = seq_lseek, | |
7b85af63 | 3698 | .release = tracing_single_release_tr, |
ee6bce52 | 3699 | .write = tracing_trace_options_write, |
bc0c38d1 SR |
3700 | }; |
3701 | ||
7bd2f24c IM |
3702 | static const char readme_msg[] = |
3703 | "tracing mini-HOWTO:\n\n" | |
22f45649 SRRH |
3704 | "# echo 0 > tracing_on : quick way to disable tracing\n" |
3705 | "# echo 1 > tracing_on : quick way to re-enable tracing\n\n" | |
3706 | " Important files:\n" | |
3707 | " trace\t\t\t- The static contents of the buffer\n" | |
3708 | "\t\t\t To clear the buffer write into this file: echo > trace\n" | |
3709 | " trace_pipe\t\t- A consuming read to see the contents of the buffer\n" | |
3710 | " current_tracer\t- function and latency tracers\n" | |
3711 | " available_tracers\t- list of configured tracers for current_tracer\n" | |
3712 | " buffer_size_kb\t- view and modify size of per cpu buffer\n" | |
3713 | " buffer_total_size_kb - view total size of all cpu buffers\n\n" | |
3714 | " trace_clock\t\t-change the clock used to order events\n" | |
3715 | " local: Per cpu clock but may not be synced across CPUs\n" | |
3716 | " global: Synced across CPUs but slows tracing down.\n" | |
3717 | " counter: Not a clock, but just an increment\n" | |
3718 | " uptime: Jiffy counter from time of boot\n" | |
3719 | " perf: Same clock that perf events use\n" | |
3720 | #ifdef CONFIG_X86_64 | |
3721 | " x86-tsc: TSC cycle counter\n" | |
3722 | #endif | |
3723 | "\n trace_marker\t\t- Writes into this file writes into the kernel buffer\n" | |
3724 | " tracing_cpumask\t- Limit which CPUs to trace\n" | |
3725 | " instances\t\t- Make sub-buffers with: mkdir instances/foo\n" | |
3726 | "\t\t\t Remove sub-buffer with rmdir\n" | |
3727 | " trace_options\t\t- Set format or modify how tracing happens\n" | |
71485c45 SRRH |
3728 | "\t\t\t Disable an option by adding a suffix 'no' to the\n" |
3729 | "\t\t\t option name\n" | |
939c7a4f | 3730 | " saved_cmdlines_size\t- echo command number in here to store comm-pid list\n" |
22f45649 SRRH |
3731 | #ifdef CONFIG_DYNAMIC_FTRACE |
3732 | "\n available_filter_functions - list of functions that can be filtered on\n" | |
71485c45 SRRH |
3733 | " set_ftrace_filter\t- echo function name in here to only trace these\n" |
3734 | "\t\t\t functions\n" | |
3735 | "\t accepts: func_full_name, *func_end, func_begin*, *func_middle*\n" | |
3736 | "\t modules: Can select a group via module\n" | |
3737 | "\t Format: :mod:<module-name>\n" | |
3738 | "\t example: echo :mod:ext3 > set_ftrace_filter\n" | |
3739 | "\t triggers: a command to perform when function is hit\n" | |
3740 | "\t Format: <function>:<trigger>[:count]\n" | |
3741 | "\t trigger: traceon, traceoff\n" | |
3742 | "\t\t enable_event:<system>:<event>\n" | |
3743 | "\t\t disable_event:<system>:<event>\n" | |
22f45649 | 3744 | #ifdef CONFIG_STACKTRACE |
71485c45 | 3745 | "\t\t stacktrace\n" |
22f45649 SRRH |
3746 | #endif |
3747 | #ifdef CONFIG_TRACER_SNAPSHOT | |
71485c45 | 3748 | "\t\t snapshot\n" |
22f45649 | 3749 | #endif |
17a280ea SRRH |
3750 | "\t\t dump\n" |
3751 | "\t\t cpudump\n" | |
71485c45 SRRH |
3752 | "\t example: echo do_fault:traceoff > set_ftrace_filter\n" |
3753 | "\t echo do_trap:traceoff:3 > set_ftrace_filter\n" | |
3754 | "\t The first one will disable tracing every time do_fault is hit\n" | |
3755 | "\t The second will disable tracing at most 3 times when do_trap is hit\n" | |
3756 | "\t The first time do trap is hit and it disables tracing, the\n" | |
3757 | "\t counter will decrement to 2. If tracing is already disabled,\n" | |
3758 | "\t the counter will not decrement. It only decrements when the\n" | |
3759 | "\t trigger did work\n" | |
3760 | "\t To remove trigger without count:\n" | |
3761 | "\t echo '!<function>:<trigger> > set_ftrace_filter\n" | |
3762 | "\t To remove trigger with a count:\n" | |
3763 | "\t echo '!<function>:<trigger>:0 > set_ftrace_filter\n" | |
22f45649 | 3764 | " set_ftrace_notrace\t- echo function name in here to never trace.\n" |
71485c45 SRRH |
3765 | "\t accepts: func_full_name, *func_end, func_begin*, *func_middle*\n" |
3766 | "\t modules: Can select a group via module command :mod:\n" | |
3767 | "\t Does not accept triggers\n" | |
22f45649 SRRH |
3768 | #endif /* CONFIG_DYNAMIC_FTRACE */ |
3769 | #ifdef CONFIG_FUNCTION_TRACER | |
71485c45 SRRH |
3770 | " set_ftrace_pid\t- Write pid(s) to only function trace those pids\n" |
3771 | "\t\t (function)\n" | |
22f45649 SRRH |
3772 | #endif |
3773 | #ifdef CONFIG_FUNCTION_GRAPH_TRACER | |
3774 | " set_graph_function\t- Trace the nested calls of a function (function_graph)\n" | |
d048a8c7 | 3775 | " set_graph_notrace\t- Do not trace the nested calls of a function (function_graph)\n" |
22f45649 SRRH |
3776 | " max_graph_depth\t- Trace a limited depth of nested calls (0 is unlimited)\n" |
3777 | #endif | |
3778 | #ifdef CONFIG_TRACER_SNAPSHOT | |
71485c45 SRRH |
3779 | "\n snapshot\t\t- Like 'trace' but shows the content of the static\n" |
3780 | "\t\t\t snapshot buffer. Read the contents for more\n" | |
3781 | "\t\t\t information\n" | |
22f45649 | 3782 | #endif |
991821c8 | 3783 | #ifdef CONFIG_STACK_TRACER |
22f45649 SRRH |
3784 | " stack_trace\t\t- Shows the max stack trace when active\n" |
3785 | " stack_max_size\t- Shows current max stack size that was traced\n" | |
71485c45 SRRH |
3786 | "\t\t\t Write into this file to reset the max size (trigger a\n" |
3787 | "\t\t\t new trace)\n" | |
22f45649 | 3788 | #ifdef CONFIG_DYNAMIC_FTRACE |
71485c45 SRRH |
3789 | " stack_trace_filter\t- Like set_ftrace_filter but limits what stack_trace\n" |
3790 | "\t\t\t traces\n" | |
22f45649 | 3791 | #endif |
991821c8 | 3792 | #endif /* CONFIG_STACK_TRACER */ |
26f25564 TZ |
3793 | " events/\t\t- Directory containing all trace event subsystems:\n" |
3794 | " enable\t\t- Write 0/1 to enable/disable tracing of all events\n" | |
3795 | " events/<system>/\t- Directory containing all trace events for <system>:\n" | |
71485c45 SRRH |
3796 | " enable\t\t- Write 0/1 to enable/disable tracing of all <system>\n" |
3797 | "\t\t\t events\n" | |
26f25564 | 3798 | " filter\t\t- If set, only events passing filter are traced\n" |
71485c45 SRRH |
3799 | " events/<system>/<event>/\t- Directory containing control files for\n" |
3800 | "\t\t\t <event>:\n" | |
26f25564 TZ |
3801 | " enable\t\t- Write 0/1 to enable/disable tracing of <event>\n" |
3802 | " filter\t\t- If set, only events passing filter are traced\n" | |
3803 | " trigger\t\t- If set, a command to perform when event is hit\n" | |
71485c45 SRRH |
3804 | "\t Format: <trigger>[:count][if <filter>]\n" |
3805 | "\t trigger: traceon, traceoff\n" | |
3806 | "\t enable_event:<system>:<event>\n" | |
3807 | "\t disable_event:<system>:<event>\n" | |
26f25564 | 3808 | #ifdef CONFIG_STACKTRACE |
71485c45 | 3809 | "\t\t stacktrace\n" |
26f25564 TZ |
3810 | #endif |
3811 | #ifdef CONFIG_TRACER_SNAPSHOT | |
71485c45 | 3812 | "\t\t snapshot\n" |
26f25564 | 3813 | #endif |
71485c45 SRRH |
3814 | "\t example: echo traceoff > events/block/block_unplug/trigger\n" |
3815 | "\t echo traceoff:3 > events/block/block_unplug/trigger\n" | |
3816 | "\t echo 'enable_event:kmem:kmalloc:3 if nr_rq > 1' > \\\n" | |
3817 | "\t events/block/block_unplug/trigger\n" | |
3818 | "\t The first disables tracing every time block_unplug is hit.\n" | |
3819 | "\t The second disables tracing the first 3 times block_unplug is hit.\n" | |
3820 | "\t The third enables the kmalloc event the first 3 times block_unplug\n" | |
3821 | "\t is hit and has value of greater than 1 for the 'nr_rq' event field.\n" | |
3822 | "\t Like function triggers, the counter is only decremented if it\n" | |
3823 | "\t enabled or disabled tracing.\n" | |
3824 | "\t To remove a trigger without a count:\n" | |
3825 | "\t echo '!<trigger> > <system>/<event>/trigger\n" | |
3826 | "\t To remove a trigger with a count:\n" | |
3827 | "\t echo '!<trigger>:0 > <system>/<event>/trigger\n" | |
3828 | "\t Filters can be ignored when removing a trigger.\n" | |
7bd2f24c IM |
3829 | ; |
3830 | ||
3831 | static ssize_t | |
3832 | tracing_readme_read(struct file *filp, char __user *ubuf, | |
3833 | size_t cnt, loff_t *ppos) | |
3834 | { | |
3835 | return simple_read_from_buffer(ubuf, cnt, ppos, | |
3836 | readme_msg, strlen(readme_msg)); | |
3837 | } | |
3838 | ||
5e2336a0 | 3839 | static const struct file_operations tracing_readme_fops = { |
c7078de1 IM |
3840 | .open = tracing_open_generic, |
3841 | .read = tracing_readme_read, | |
b444786f | 3842 | .llseek = generic_file_llseek, |
7bd2f24c IM |
3843 | }; |
3844 | ||
42584c81 YY |
3845 | static void *saved_cmdlines_next(struct seq_file *m, void *v, loff_t *pos) |
3846 | { | |
3847 | unsigned int *ptr = v; | |
69abe6a5 | 3848 | |
42584c81 YY |
3849 | if (*pos || m->count) |
3850 | ptr++; | |
69abe6a5 | 3851 | |
42584c81 | 3852 | (*pos)++; |
69abe6a5 | 3853 | |
939c7a4f YY |
3854 | for (; ptr < &savedcmd->map_cmdline_to_pid[savedcmd->cmdline_num]; |
3855 | ptr++) { | |
42584c81 YY |
3856 | if (*ptr == -1 || *ptr == NO_CMDLINE_MAP) |
3857 | continue; | |
69abe6a5 | 3858 | |
42584c81 YY |
3859 | return ptr; |
3860 | } | |
69abe6a5 | 3861 | |
42584c81 YY |
3862 | return NULL; |
3863 | } | |
3864 | ||
3865 | static void *saved_cmdlines_start(struct seq_file *m, loff_t *pos) | |
3866 | { | |
3867 | void *v; | |
3868 | loff_t l = 0; | |
69abe6a5 | 3869 | |
4c27e756 SRRH |
3870 | preempt_disable(); |
3871 | arch_spin_lock(&trace_cmdline_lock); | |
3872 | ||
939c7a4f | 3873 | v = &savedcmd->map_cmdline_to_pid[0]; |
42584c81 YY |
3874 | while (l <= *pos) { |
3875 | v = saved_cmdlines_next(m, v, &l); | |
3876 | if (!v) | |
3877 | return NULL; | |
69abe6a5 AP |
3878 | } |
3879 | ||
42584c81 YY |
3880 | return v; |
3881 | } | |
3882 | ||
3883 | static void saved_cmdlines_stop(struct seq_file *m, void *v) | |
3884 | { | |
4c27e756 SRRH |
3885 | arch_spin_unlock(&trace_cmdline_lock); |
3886 | preempt_enable(); | |
42584c81 | 3887 | } |
69abe6a5 | 3888 | |
42584c81 YY |
3889 | static int saved_cmdlines_show(struct seq_file *m, void *v) |
3890 | { | |
3891 | char buf[TASK_COMM_LEN]; | |
3892 | unsigned int *pid = v; | |
69abe6a5 | 3893 | |
4c27e756 | 3894 | __trace_find_cmdline(*pid, buf); |
42584c81 YY |
3895 | seq_printf(m, "%d %s\n", *pid, buf); |
3896 | return 0; | |
3897 | } | |
3898 | ||
3899 | static const struct seq_operations tracing_saved_cmdlines_seq_ops = { | |
3900 | .start = saved_cmdlines_start, | |
3901 | .next = saved_cmdlines_next, | |
3902 | .stop = saved_cmdlines_stop, | |
3903 | .show = saved_cmdlines_show, | |
3904 | }; | |
3905 | ||
3906 | static int tracing_saved_cmdlines_open(struct inode *inode, struct file *filp) | |
3907 | { | |
3908 | if (tracing_disabled) | |
3909 | return -ENODEV; | |
3910 | ||
3911 | return seq_open(filp, &tracing_saved_cmdlines_seq_ops); | |
69abe6a5 AP |
3912 | } |
3913 | ||
3914 | static const struct file_operations tracing_saved_cmdlines_fops = { | |
42584c81 YY |
3915 | .open = tracing_saved_cmdlines_open, |
3916 | .read = seq_read, | |
3917 | .llseek = seq_lseek, | |
3918 | .release = seq_release, | |
69abe6a5 AP |
3919 | }; |
3920 | ||
939c7a4f YY |
3921 | static ssize_t |
3922 | tracing_saved_cmdlines_size_read(struct file *filp, char __user *ubuf, | |
3923 | size_t cnt, loff_t *ppos) | |
3924 | { | |
3925 | char buf[64]; | |
3926 | int r; | |
3927 | ||
3928 | arch_spin_lock(&trace_cmdline_lock); | |
a6af8fbf | 3929 | r = scnprintf(buf, sizeof(buf), "%u\n", savedcmd->cmdline_num); |
939c7a4f YY |
3930 | arch_spin_unlock(&trace_cmdline_lock); |
3931 | ||
3932 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, r); | |
3933 | } | |
3934 | ||
3935 | static void free_saved_cmdlines_buffer(struct saved_cmdlines_buffer *s) | |
3936 | { | |
3937 | kfree(s->saved_cmdlines); | |
3938 | kfree(s->map_cmdline_to_pid); | |
3939 | kfree(s); | |
3940 | } | |
3941 | ||
3942 | static int tracing_resize_saved_cmdlines(unsigned int val) | |
3943 | { | |
3944 | struct saved_cmdlines_buffer *s, *savedcmd_temp; | |
3945 | ||
a6af8fbf | 3946 | s = kmalloc(sizeof(*s), GFP_KERNEL); |
939c7a4f YY |
3947 | if (!s) |
3948 | return -ENOMEM; | |
3949 | ||
3950 | if (allocate_cmdlines_buffer(val, s) < 0) { | |
3951 | kfree(s); | |
3952 | return -ENOMEM; | |
3953 | } | |
3954 | ||
3955 | arch_spin_lock(&trace_cmdline_lock); | |
3956 | savedcmd_temp = savedcmd; | |
3957 | savedcmd = s; | |
3958 | arch_spin_unlock(&trace_cmdline_lock); | |
3959 | free_saved_cmdlines_buffer(savedcmd_temp); | |
3960 | ||
3961 | return 0; | |
3962 | } | |
3963 | ||
3964 | static ssize_t | |
3965 | tracing_saved_cmdlines_size_write(struct file *filp, const char __user *ubuf, | |
3966 | size_t cnt, loff_t *ppos) | |
3967 | { | |
3968 | unsigned long val; | |
3969 | int ret; | |
3970 | ||
3971 | ret = kstrtoul_from_user(ubuf, cnt, 10, &val); | |
3972 | if (ret) | |
3973 | return ret; | |
3974 | ||
3975 | /* must have at least 1 entry or less than PID_MAX_DEFAULT */ | |
3976 | if (!val || val > PID_MAX_DEFAULT) | |
3977 | return -EINVAL; | |
3978 | ||
3979 | ret = tracing_resize_saved_cmdlines((unsigned int)val); | |
3980 | if (ret < 0) | |
3981 | return ret; | |
3982 | ||
3983 | *ppos += cnt; | |
3984 | ||
3985 | return cnt; | |
3986 | } | |
3987 | ||
3988 | static const struct file_operations tracing_saved_cmdlines_size_fops = { | |
3989 | .open = tracing_open_generic, | |
3990 | .read = tracing_saved_cmdlines_size_read, | |
3991 | .write = tracing_saved_cmdlines_size_write, | |
3992 | }; | |
3993 | ||
9828413d SRRH |
3994 | #ifdef CONFIG_TRACE_ENUM_MAP_FILE |
3995 | static union trace_enum_map_item * | |
3996 | update_enum_map(union trace_enum_map_item *ptr) | |
3997 | { | |
3998 | if (!ptr->map.enum_string) { | |
3999 | if (ptr->tail.next) { | |
4000 | ptr = ptr->tail.next; | |
4001 | /* Set ptr to the next real item (skip head) */ | |
4002 | ptr++; | |
4003 | } else | |
4004 | return NULL; | |
4005 | } | |
4006 | return ptr; | |
4007 | } | |
4008 | ||
4009 | static void *enum_map_next(struct seq_file *m, void *v, loff_t *pos) | |
4010 | { | |
4011 | union trace_enum_map_item *ptr = v; | |
4012 | ||
4013 | /* | |
4014 | * Paranoid! If ptr points to end, we don't want to increment past it. | |
4015 | * This really should never happen. | |
4016 | */ | |
4017 | ptr = update_enum_map(ptr); | |
4018 | if (WARN_ON_ONCE(!ptr)) | |
4019 | return NULL; | |
4020 | ||
4021 | ptr++; | |
4022 | ||
4023 | (*pos)++; | |
4024 | ||
4025 | ptr = update_enum_map(ptr); | |
4026 | ||
4027 | return ptr; | |
4028 | } | |
4029 | ||
4030 | static void *enum_map_start(struct seq_file *m, loff_t *pos) | |
4031 | { | |
4032 | union trace_enum_map_item *v; | |
4033 | loff_t l = 0; | |
4034 | ||
4035 | mutex_lock(&trace_enum_mutex); | |
4036 | ||
4037 | v = trace_enum_maps; | |
4038 | if (v) | |
4039 | v++; | |
4040 | ||
4041 | while (v && l < *pos) { | |
4042 | v = enum_map_next(m, v, &l); | |
4043 | } | |
4044 | ||
4045 | return v; | |
4046 | } | |
4047 | ||
4048 | static void enum_map_stop(struct seq_file *m, void *v) | |
4049 | { | |
4050 | mutex_unlock(&trace_enum_mutex); | |
4051 | } | |
4052 | ||
4053 | static int enum_map_show(struct seq_file *m, void *v) | |
4054 | { | |
4055 | union trace_enum_map_item *ptr = v; | |
4056 | ||
4057 | seq_printf(m, "%s %ld (%s)\n", | |
4058 | ptr->map.enum_string, ptr->map.enum_value, | |
4059 | ptr->map.system); | |
4060 | ||
4061 | return 0; | |
4062 | } | |
4063 | ||
4064 | static const struct seq_operations tracing_enum_map_seq_ops = { | |
4065 | .start = enum_map_start, | |
4066 | .next = enum_map_next, | |
4067 | .stop = enum_map_stop, | |
4068 | .show = enum_map_show, | |
4069 | }; | |
4070 | ||
4071 | static int tracing_enum_map_open(struct inode *inode, struct file *filp) | |
4072 | { | |
4073 | if (tracing_disabled) | |
4074 | return -ENODEV; | |
4075 | ||
4076 | return seq_open(filp, &tracing_enum_map_seq_ops); | |
4077 | } | |
4078 | ||
4079 | static const struct file_operations tracing_enum_map_fops = { | |
4080 | .open = tracing_enum_map_open, | |
4081 | .read = seq_read, | |
4082 | .llseek = seq_lseek, | |
4083 | .release = seq_release, | |
4084 | }; | |
4085 | ||
4086 | static inline union trace_enum_map_item * | |
4087 | trace_enum_jmp_to_tail(union trace_enum_map_item *ptr) | |
4088 | { | |
4089 | /* Return tail of array given the head */ | |
4090 | return ptr + ptr->head.length + 1; | |
4091 | } | |
4092 | ||
4093 | static void | |
4094 | trace_insert_enum_map_file(struct module *mod, struct trace_enum_map **start, | |
4095 | int len) | |
4096 | { | |
4097 | struct trace_enum_map **stop; | |
4098 | struct trace_enum_map **map; | |
4099 | union trace_enum_map_item *map_array; | |
4100 | union trace_enum_map_item *ptr; | |
4101 | ||
4102 | stop = start + len; | |
4103 | ||
4104 | /* | |
4105 | * The trace_enum_maps contains the map plus a head and tail item, | |
4106 | * where the head holds the module and length of array, and the | |
4107 | * tail holds a pointer to the next list. | |
4108 | */ | |
4109 | map_array = kmalloc(sizeof(*map_array) * (len + 2), GFP_KERNEL); | |
4110 | if (!map_array) { | |
4111 | pr_warning("Unable to allocate trace enum mapping\n"); | |
4112 | return; | |
4113 | } | |
4114 | ||
4115 | mutex_lock(&trace_enum_mutex); | |
4116 | ||
4117 | if (!trace_enum_maps) | |
4118 | trace_enum_maps = map_array; | |
4119 | else { | |
4120 | ptr = trace_enum_maps; | |
4121 | for (;;) { | |
4122 | ptr = trace_enum_jmp_to_tail(ptr); | |
4123 | if (!ptr->tail.next) | |
4124 | break; | |
4125 | ptr = ptr->tail.next; | |
4126 | ||
4127 | } | |
4128 | ptr->tail.next = map_array; | |
4129 | } | |
4130 | map_array->head.mod = mod; | |
4131 | map_array->head.length = len; | |
4132 | map_array++; | |
4133 | ||
4134 | for (map = start; (unsigned long)map < (unsigned long)stop; map++) { | |
4135 | map_array->map = **map; | |
4136 | map_array++; | |
4137 | } | |
4138 | memset(map_array, 0, sizeof(*map_array)); | |
4139 | ||
4140 | mutex_unlock(&trace_enum_mutex); | |
4141 | } | |
4142 | ||
4143 | static void trace_create_enum_file(struct dentry *d_tracer) | |
4144 | { | |
4145 | trace_create_file("enum_map", 0444, d_tracer, | |
4146 | NULL, &tracing_enum_map_fops); | |
4147 | } | |
4148 | ||
4149 | #else /* CONFIG_TRACE_ENUM_MAP_FILE */ | |
4150 | static inline void trace_create_enum_file(struct dentry *d_tracer) { } | |
4151 | static inline void trace_insert_enum_map_file(struct module *mod, | |
4152 | struct trace_enum_map **start, int len) { } | |
4153 | #endif /* !CONFIG_TRACE_ENUM_MAP_FILE */ | |
4154 | ||
4155 | static void trace_insert_enum_map(struct module *mod, | |
4156 | struct trace_enum_map **start, int len) | |
0c564a53 SRRH |
4157 | { |
4158 | struct trace_enum_map **map; | |
0c564a53 SRRH |
4159 | |
4160 | if (len <= 0) | |
4161 | return; | |
4162 | ||
4163 | map = start; | |
4164 | ||
4165 | trace_event_enum_update(map, len); | |
9828413d SRRH |
4166 | |
4167 | trace_insert_enum_map_file(mod, start, len); | |
0c564a53 SRRH |
4168 | } |
4169 | ||
bc0c38d1 SR |
4170 | static ssize_t |
4171 | tracing_set_trace_read(struct file *filp, char __user *ubuf, | |
4172 | size_t cnt, loff_t *ppos) | |
4173 | { | |
2b6080f2 | 4174 | struct trace_array *tr = filp->private_data; |
ee6c2c1b | 4175 | char buf[MAX_TRACER_SIZE+2]; |
bc0c38d1 SR |
4176 | int r; |
4177 | ||
4178 | mutex_lock(&trace_types_lock); | |
2b6080f2 | 4179 | r = sprintf(buf, "%s\n", tr->current_trace->name); |
bc0c38d1 SR |
4180 | mutex_unlock(&trace_types_lock); |
4181 | ||
4bf39a94 | 4182 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, r); |
bc0c38d1 SR |
4183 | } |
4184 | ||
b6f11df2 ACM |
4185 | int tracer_init(struct tracer *t, struct trace_array *tr) |
4186 | { | |
12883efb | 4187 | tracing_reset_online_cpus(&tr->trace_buffer); |
b6f11df2 ACM |
4188 | return t->init(tr); |
4189 | } | |
4190 | ||
12883efb | 4191 | static void set_buffer_entries(struct trace_buffer *buf, unsigned long val) |
438ced17 VN |
4192 | { |
4193 | int cpu; | |
737223fb | 4194 | |
438ced17 | 4195 | for_each_tracing_cpu(cpu) |
12883efb | 4196 | per_cpu_ptr(buf->data, cpu)->entries = val; |
438ced17 VN |
4197 | } |
4198 | ||
12883efb | 4199 | #ifdef CONFIG_TRACER_MAX_TRACE |
d60da506 | 4200 | /* resize @tr's buffer to the size of @size_tr's entries */ |
12883efb SRRH |
4201 | static int resize_buffer_duplicate_size(struct trace_buffer *trace_buf, |
4202 | struct trace_buffer *size_buf, int cpu_id) | |
d60da506 HT |
4203 | { |
4204 | int cpu, ret = 0; | |
4205 | ||
4206 | if (cpu_id == RING_BUFFER_ALL_CPUS) { | |
4207 | for_each_tracing_cpu(cpu) { | |
12883efb SRRH |
4208 | ret = ring_buffer_resize(trace_buf->buffer, |
4209 | per_cpu_ptr(size_buf->data, cpu)->entries, cpu); | |
d60da506 HT |
4210 | if (ret < 0) |
4211 | break; | |
12883efb SRRH |
4212 | per_cpu_ptr(trace_buf->data, cpu)->entries = |
4213 | per_cpu_ptr(size_buf->data, cpu)->entries; | |
d60da506 HT |
4214 | } |
4215 | } else { | |
12883efb SRRH |
4216 | ret = ring_buffer_resize(trace_buf->buffer, |
4217 | per_cpu_ptr(size_buf->data, cpu_id)->entries, cpu_id); | |
d60da506 | 4218 | if (ret == 0) |
12883efb SRRH |
4219 | per_cpu_ptr(trace_buf->data, cpu_id)->entries = |
4220 | per_cpu_ptr(size_buf->data, cpu_id)->entries; | |
d60da506 HT |
4221 | } |
4222 | ||
4223 | return ret; | |
4224 | } | |
12883efb | 4225 | #endif /* CONFIG_TRACER_MAX_TRACE */ |
d60da506 | 4226 | |
2b6080f2 SR |
4227 | static int __tracing_resize_ring_buffer(struct trace_array *tr, |
4228 | unsigned long size, int cpu) | |
73c5162a SR |
4229 | { |
4230 | int ret; | |
4231 | ||
4232 | /* | |
4233 | * If kernel or user changes the size of the ring buffer | |
a123c52b SR |
4234 | * we use the size that was given, and we can forget about |
4235 | * expanding it later. | |
73c5162a | 4236 | */ |
55034cd6 | 4237 | ring_buffer_expanded = true; |
73c5162a | 4238 | |
b382ede6 | 4239 | /* May be called before buffers are initialized */ |
12883efb | 4240 | if (!tr->trace_buffer.buffer) |
b382ede6 SR |
4241 | return 0; |
4242 | ||
12883efb | 4243 | ret = ring_buffer_resize(tr->trace_buffer.buffer, size, cpu); |
73c5162a SR |
4244 | if (ret < 0) |
4245 | return ret; | |
4246 | ||
12883efb | 4247 | #ifdef CONFIG_TRACER_MAX_TRACE |
2b6080f2 SR |
4248 | if (!(tr->flags & TRACE_ARRAY_FL_GLOBAL) || |
4249 | !tr->current_trace->use_max_tr) | |
ef710e10 KM |
4250 | goto out; |
4251 | ||
12883efb | 4252 | ret = ring_buffer_resize(tr->max_buffer.buffer, size, cpu); |
73c5162a | 4253 | if (ret < 0) { |
12883efb SRRH |
4254 | int r = resize_buffer_duplicate_size(&tr->trace_buffer, |
4255 | &tr->trace_buffer, cpu); | |
73c5162a | 4256 | if (r < 0) { |
a123c52b SR |
4257 | /* |
4258 | * AARGH! We are left with different | |
4259 | * size max buffer!!!! | |
4260 | * The max buffer is our "snapshot" buffer. | |
4261 | * When a tracer needs a snapshot (one of the | |
4262 | * latency tracers), it swaps the max buffer | |
4263 | * with the saved snap shot. We succeeded to | |
4264 | * update the size of the main buffer, but failed to | |
4265 | * update the size of the max buffer. But when we tried | |
4266 | * to reset the main buffer to the original size, we | |
4267 | * failed there too. This is very unlikely to | |
4268 | * happen, but if it does, warn and kill all | |
4269 | * tracing. | |
4270 | */ | |
73c5162a SR |
4271 | WARN_ON(1); |
4272 | tracing_disabled = 1; | |
4273 | } | |
4274 | return ret; | |
4275 | } | |
4276 | ||
438ced17 | 4277 | if (cpu == RING_BUFFER_ALL_CPUS) |
12883efb | 4278 | set_buffer_entries(&tr->max_buffer, size); |
438ced17 | 4279 | else |
12883efb | 4280 | per_cpu_ptr(tr->max_buffer.data, cpu)->entries = size; |
438ced17 | 4281 | |
ef710e10 | 4282 | out: |
12883efb SRRH |
4283 | #endif /* CONFIG_TRACER_MAX_TRACE */ |
4284 | ||
438ced17 | 4285 | if (cpu == RING_BUFFER_ALL_CPUS) |
12883efb | 4286 | set_buffer_entries(&tr->trace_buffer, size); |
438ced17 | 4287 | else |
12883efb | 4288 | per_cpu_ptr(tr->trace_buffer.data, cpu)->entries = size; |
73c5162a SR |
4289 | |
4290 | return ret; | |
4291 | } | |
4292 | ||
2b6080f2 SR |
4293 | static ssize_t tracing_resize_ring_buffer(struct trace_array *tr, |
4294 | unsigned long size, int cpu_id) | |
4f271a2a | 4295 | { |
83f40318 | 4296 | int ret = size; |
4f271a2a VN |
4297 | |
4298 | mutex_lock(&trace_types_lock); | |
4299 | ||
438ced17 VN |
4300 | if (cpu_id != RING_BUFFER_ALL_CPUS) { |
4301 | /* make sure, this cpu is enabled in the mask */ | |
4302 | if (!cpumask_test_cpu(cpu_id, tracing_buffer_mask)) { | |
4303 | ret = -EINVAL; | |
4304 | goto out; | |
4305 | } | |
4306 | } | |
4f271a2a | 4307 | |
2b6080f2 | 4308 | ret = __tracing_resize_ring_buffer(tr, size, cpu_id); |
4f271a2a VN |
4309 | if (ret < 0) |
4310 | ret = -ENOMEM; | |
4311 | ||
438ced17 | 4312 | out: |
4f271a2a VN |
4313 | mutex_unlock(&trace_types_lock); |
4314 | ||
4315 | return ret; | |
4316 | } | |
4317 | ||
ef710e10 | 4318 | |
1852fcce SR |
4319 | /** |
4320 | * tracing_update_buffers - used by tracing facility to expand ring buffers | |
4321 | * | |
4322 | * To save on memory when the tracing is never used on a system with it | |
4323 | * configured in. The ring buffers are set to a minimum size. But once | |
4324 | * a user starts to use the tracing facility, then they need to grow | |
4325 | * to their default size. | |
4326 | * | |
4327 | * This function is to be called when a tracer is about to be used. | |
4328 | */ | |
4329 | int tracing_update_buffers(void) | |
4330 | { | |
4331 | int ret = 0; | |
4332 | ||
1027fcb2 | 4333 | mutex_lock(&trace_types_lock); |
1852fcce | 4334 | if (!ring_buffer_expanded) |
2b6080f2 | 4335 | ret = __tracing_resize_ring_buffer(&global_trace, trace_buf_size, |
438ced17 | 4336 | RING_BUFFER_ALL_CPUS); |
1027fcb2 | 4337 | mutex_unlock(&trace_types_lock); |
1852fcce SR |
4338 | |
4339 | return ret; | |
4340 | } | |
4341 | ||
577b785f SR |
4342 | struct trace_option_dentry; |
4343 | ||
37aea98b | 4344 | static void |
2b6080f2 | 4345 | create_trace_option_files(struct trace_array *tr, struct tracer *tracer); |
577b785f | 4346 | |
6b450d25 SRRH |
4347 | /* |
4348 | * Used to clear out the tracer before deletion of an instance. | |
4349 | * Must have trace_types_lock held. | |
4350 | */ | |
4351 | static void tracing_set_nop(struct trace_array *tr) | |
4352 | { | |
4353 | if (tr->current_trace == &nop_trace) | |
4354 | return; | |
4355 | ||
50512ab5 | 4356 | tr->current_trace->enabled--; |
6b450d25 SRRH |
4357 | |
4358 | if (tr->current_trace->reset) | |
4359 | tr->current_trace->reset(tr); | |
4360 | ||
4361 | tr->current_trace = &nop_trace; | |
4362 | } | |
4363 | ||
41d9c0be | 4364 | static void add_tracer_options(struct trace_array *tr, struct tracer *t) |
bc0c38d1 | 4365 | { |
09d23a1d SRRH |
4366 | /* Only enable if the directory has been created already. */ |
4367 | if (!tr->dir) | |
4368 | return; | |
4369 | ||
37aea98b | 4370 | create_trace_option_files(tr, t); |
09d23a1d SRRH |
4371 | } |
4372 | ||
4373 | static int tracing_set_tracer(struct trace_array *tr, const char *buf) | |
4374 | { | |
bc0c38d1 | 4375 | struct tracer *t; |
12883efb | 4376 | #ifdef CONFIG_TRACER_MAX_TRACE |
34600f0e | 4377 | bool had_max_tr; |
12883efb | 4378 | #endif |
d9e54076 | 4379 | int ret = 0; |
bc0c38d1 | 4380 | |
1027fcb2 SR |
4381 | mutex_lock(&trace_types_lock); |
4382 | ||
73c5162a | 4383 | if (!ring_buffer_expanded) { |
2b6080f2 | 4384 | ret = __tracing_resize_ring_buffer(tr, trace_buf_size, |
438ced17 | 4385 | RING_BUFFER_ALL_CPUS); |
73c5162a | 4386 | if (ret < 0) |
59f586db | 4387 | goto out; |
73c5162a SR |
4388 | ret = 0; |
4389 | } | |
4390 | ||
bc0c38d1 SR |
4391 | for (t = trace_types; t; t = t->next) { |
4392 | if (strcmp(t->name, buf) == 0) | |
4393 | break; | |
4394 | } | |
c2931e05 FW |
4395 | if (!t) { |
4396 | ret = -EINVAL; | |
4397 | goto out; | |
4398 | } | |
2b6080f2 | 4399 | if (t == tr->current_trace) |
bc0c38d1 SR |
4400 | goto out; |
4401 | ||
607e2ea1 SRRH |
4402 | /* Some tracers are only allowed for the top level buffer */ |
4403 | if (!trace_ok_for_array(t, tr)) { | |
4404 | ret = -EINVAL; | |
4405 | goto out; | |
4406 | } | |
4407 | ||
cf6ab6d9 SRRH |
4408 | /* If trace pipe files are being read, we can't change the tracer */ |
4409 | if (tr->current_trace->ref) { | |
4410 | ret = -EBUSY; | |
4411 | goto out; | |
4412 | } | |
4413 | ||
9f029e83 | 4414 | trace_branch_disable(); |
613f04a0 | 4415 | |
50512ab5 | 4416 | tr->current_trace->enabled--; |
613f04a0 | 4417 | |
2b6080f2 SR |
4418 | if (tr->current_trace->reset) |
4419 | tr->current_trace->reset(tr); | |
34600f0e | 4420 | |
12883efb | 4421 | /* Current trace needs to be nop_trace before synchronize_sched */ |
2b6080f2 | 4422 | tr->current_trace = &nop_trace; |
34600f0e | 4423 | |
45ad21ca SRRH |
4424 | #ifdef CONFIG_TRACER_MAX_TRACE |
4425 | had_max_tr = tr->allocated_snapshot; | |
34600f0e SR |
4426 | |
4427 | if (had_max_tr && !t->use_max_tr) { | |
4428 | /* | |
4429 | * We need to make sure that the update_max_tr sees that | |
4430 | * current_trace changed to nop_trace to keep it from | |
4431 | * swapping the buffers after we resize it. | |
4432 | * The update_max_tr is called from interrupts disabled | |
4433 | * so a synchronized_sched() is sufficient. | |
4434 | */ | |
4435 | synchronize_sched(); | |
3209cff4 | 4436 | free_snapshot(tr); |
ef710e10 | 4437 | } |
12883efb | 4438 | #endif |
12883efb SRRH |
4439 | |
4440 | #ifdef CONFIG_TRACER_MAX_TRACE | |
34600f0e | 4441 | if (t->use_max_tr && !had_max_tr) { |
3209cff4 | 4442 | ret = alloc_snapshot(tr); |
d60da506 HT |
4443 | if (ret < 0) |
4444 | goto out; | |
ef710e10 | 4445 | } |
12883efb | 4446 | #endif |
577b785f | 4447 | |
1c80025a | 4448 | if (t->init) { |
b6f11df2 | 4449 | ret = tracer_init(t, tr); |
1c80025a FW |
4450 | if (ret) |
4451 | goto out; | |
4452 | } | |
bc0c38d1 | 4453 | |
2b6080f2 | 4454 | tr->current_trace = t; |
50512ab5 | 4455 | tr->current_trace->enabled++; |
9f029e83 | 4456 | trace_branch_enable(tr); |
bc0c38d1 SR |
4457 | out: |
4458 | mutex_unlock(&trace_types_lock); | |
4459 | ||
d9e54076 PZ |
4460 | return ret; |
4461 | } | |
4462 | ||
4463 | static ssize_t | |
4464 | tracing_set_trace_write(struct file *filp, const char __user *ubuf, | |
4465 | size_t cnt, loff_t *ppos) | |
4466 | { | |
607e2ea1 | 4467 | struct trace_array *tr = filp->private_data; |
ee6c2c1b | 4468 | char buf[MAX_TRACER_SIZE+1]; |
d9e54076 PZ |
4469 | int i; |
4470 | size_t ret; | |
e6e7a65a FW |
4471 | int err; |
4472 | ||
4473 | ret = cnt; | |
d9e54076 | 4474 | |
ee6c2c1b LZ |
4475 | if (cnt > MAX_TRACER_SIZE) |
4476 | cnt = MAX_TRACER_SIZE; | |
d9e54076 PZ |
4477 | |
4478 | if (copy_from_user(&buf, ubuf, cnt)) | |
4479 | return -EFAULT; | |
4480 | ||
4481 | buf[cnt] = 0; | |
4482 | ||
4483 | /* strip ending whitespace. */ | |
4484 | for (i = cnt - 1; i > 0 && isspace(buf[i]); i--) | |
4485 | buf[i] = 0; | |
4486 | ||
607e2ea1 | 4487 | err = tracing_set_tracer(tr, buf); |
e6e7a65a FW |
4488 | if (err) |
4489 | return err; | |
d9e54076 | 4490 | |
cf8517cf | 4491 | *ppos += ret; |
bc0c38d1 | 4492 | |
c2931e05 | 4493 | return ret; |
bc0c38d1 SR |
4494 | } |
4495 | ||
4496 | static ssize_t | |
6508fa76 SF |
4497 | tracing_nsecs_read(unsigned long *ptr, char __user *ubuf, |
4498 | size_t cnt, loff_t *ppos) | |
bc0c38d1 | 4499 | { |
bc0c38d1 SR |
4500 | char buf[64]; |
4501 | int r; | |
4502 | ||
cffae437 | 4503 | r = snprintf(buf, sizeof(buf), "%ld\n", |
bc0c38d1 | 4504 | *ptr == (unsigned long)-1 ? -1 : nsecs_to_usecs(*ptr)); |
cffae437 SR |
4505 | if (r > sizeof(buf)) |
4506 | r = sizeof(buf); | |
4bf39a94 | 4507 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, r); |
bc0c38d1 SR |
4508 | } |
4509 | ||
4510 | static ssize_t | |
6508fa76 SF |
4511 | tracing_nsecs_write(unsigned long *ptr, const char __user *ubuf, |
4512 | size_t cnt, loff_t *ppos) | |
bc0c38d1 | 4513 | { |
5e39841c | 4514 | unsigned long val; |
c6caeeb1 | 4515 | int ret; |
bc0c38d1 | 4516 | |
22fe9b54 PH |
4517 | ret = kstrtoul_from_user(ubuf, cnt, 10, &val); |
4518 | if (ret) | |
c6caeeb1 | 4519 | return ret; |
bc0c38d1 SR |
4520 | |
4521 | *ptr = val * 1000; | |
4522 | ||
4523 | return cnt; | |
4524 | } | |
4525 | ||
6508fa76 SF |
4526 | static ssize_t |
4527 | tracing_thresh_read(struct file *filp, char __user *ubuf, | |
4528 | size_t cnt, loff_t *ppos) | |
4529 | { | |
4530 | return tracing_nsecs_read(&tracing_thresh, ubuf, cnt, ppos); | |
4531 | } | |
4532 | ||
4533 | static ssize_t | |
4534 | tracing_thresh_write(struct file *filp, const char __user *ubuf, | |
4535 | size_t cnt, loff_t *ppos) | |
4536 | { | |
4537 | struct trace_array *tr = filp->private_data; | |
4538 | int ret; | |
4539 | ||
4540 | mutex_lock(&trace_types_lock); | |
4541 | ret = tracing_nsecs_write(&tracing_thresh, ubuf, cnt, ppos); | |
4542 | if (ret < 0) | |
4543 | goto out; | |
4544 | ||
4545 | if (tr->current_trace->update_thresh) { | |
4546 | ret = tr->current_trace->update_thresh(tr); | |
4547 | if (ret < 0) | |
4548 | goto out; | |
4549 | } | |
4550 | ||
4551 | ret = cnt; | |
4552 | out: | |
4553 | mutex_unlock(&trace_types_lock); | |
4554 | ||
4555 | return ret; | |
4556 | } | |
4557 | ||
4558 | static ssize_t | |
4559 | tracing_max_lat_read(struct file *filp, char __user *ubuf, | |
4560 | size_t cnt, loff_t *ppos) | |
4561 | { | |
4562 | return tracing_nsecs_read(filp->private_data, ubuf, cnt, ppos); | |
4563 | } | |
4564 | ||
4565 | static ssize_t | |
4566 | tracing_max_lat_write(struct file *filp, const char __user *ubuf, | |
4567 | size_t cnt, loff_t *ppos) | |
4568 | { | |
4569 | return tracing_nsecs_write(filp->private_data, ubuf, cnt, ppos); | |
4570 | } | |
4571 | ||
b3806b43 SR |
4572 | static int tracing_open_pipe(struct inode *inode, struct file *filp) |
4573 | { | |
15544209 | 4574 | struct trace_array *tr = inode->i_private; |
b3806b43 | 4575 | struct trace_iterator *iter; |
b04cc6b1 | 4576 | int ret = 0; |
b3806b43 SR |
4577 | |
4578 | if (tracing_disabled) | |
4579 | return -ENODEV; | |
4580 | ||
7b85af63 SRRH |
4581 | if (trace_array_get(tr) < 0) |
4582 | return -ENODEV; | |
4583 | ||
b04cc6b1 FW |
4584 | mutex_lock(&trace_types_lock); |
4585 | ||
b3806b43 SR |
4586 | /* create a buffer to store the information to pass to userspace */ |
4587 | iter = kzalloc(sizeof(*iter), GFP_KERNEL); | |
b04cc6b1 FW |
4588 | if (!iter) { |
4589 | ret = -ENOMEM; | |
f77d09a3 | 4590 | __trace_array_put(tr); |
b04cc6b1 FW |
4591 | goto out; |
4592 | } | |
b3806b43 | 4593 | |
3a161d99 | 4594 | trace_seq_init(&iter->seq); |
d716ff71 | 4595 | iter->trace = tr->current_trace; |
d7350c3f | 4596 | |
4462344e | 4597 | if (!alloc_cpumask_var(&iter->started, GFP_KERNEL)) { |
b04cc6b1 | 4598 | ret = -ENOMEM; |
d7350c3f | 4599 | goto fail; |
4462344e RR |
4600 | } |
4601 | ||
a309720c | 4602 | /* trace pipe does not show start of buffer */ |
4462344e | 4603 | cpumask_setall(iter->started); |
a309720c | 4604 | |
983f938a | 4605 | if (tr->trace_flags & TRACE_ITER_LATENCY_FMT) |
112f38a7 SR |
4606 | iter->iter_flags |= TRACE_FILE_LAT_FMT; |
4607 | ||
8be0709f | 4608 | /* Output in nanoseconds only if we are using a clock in nanoseconds. */ |
58e8eedf | 4609 | if (trace_clocks[tr->clock_id].in_ns) |
8be0709f DS |
4610 | iter->iter_flags |= TRACE_FILE_TIME_IN_NS; |
4611 | ||
15544209 ON |
4612 | iter->tr = tr; |
4613 | iter->trace_buffer = &tr->trace_buffer; | |
4614 | iter->cpu_file = tracing_get_cpu(inode); | |
d7350c3f | 4615 | mutex_init(&iter->mutex); |
b3806b43 SR |
4616 | filp->private_data = iter; |
4617 | ||
107bad8b SR |
4618 | if (iter->trace->pipe_open) |
4619 | iter->trace->pipe_open(iter); | |
107bad8b | 4620 | |
b444786f | 4621 | nonseekable_open(inode, filp); |
cf6ab6d9 SRRH |
4622 | |
4623 | tr->current_trace->ref++; | |
b04cc6b1 FW |
4624 | out: |
4625 | mutex_unlock(&trace_types_lock); | |
4626 | return ret; | |
d7350c3f FW |
4627 | |
4628 | fail: | |
4629 | kfree(iter->trace); | |
4630 | kfree(iter); | |
7b85af63 | 4631 | __trace_array_put(tr); |
d7350c3f FW |
4632 | mutex_unlock(&trace_types_lock); |
4633 | return ret; | |
b3806b43 SR |
4634 | } |
4635 | ||
4636 | static int tracing_release_pipe(struct inode *inode, struct file *file) | |
4637 | { | |
4638 | struct trace_iterator *iter = file->private_data; | |
15544209 | 4639 | struct trace_array *tr = inode->i_private; |
b3806b43 | 4640 | |
b04cc6b1 FW |
4641 | mutex_lock(&trace_types_lock); |
4642 | ||
cf6ab6d9 SRRH |
4643 | tr->current_trace->ref--; |
4644 | ||
29bf4a5e | 4645 | if (iter->trace->pipe_close) |
c521efd1 SR |
4646 | iter->trace->pipe_close(iter); |
4647 | ||
b04cc6b1 FW |
4648 | mutex_unlock(&trace_types_lock); |
4649 | ||
4462344e | 4650 | free_cpumask_var(iter->started); |
d7350c3f | 4651 | mutex_destroy(&iter->mutex); |
b3806b43 | 4652 | kfree(iter); |
b3806b43 | 4653 | |
7b85af63 SRRH |
4654 | trace_array_put(tr); |
4655 | ||
b3806b43 SR |
4656 | return 0; |
4657 | } | |
4658 | ||
2a2cc8f7 | 4659 | static unsigned int |
cc60cdc9 | 4660 | trace_poll(struct trace_iterator *iter, struct file *filp, poll_table *poll_table) |
2a2cc8f7 | 4661 | { |
983f938a SRRH |
4662 | struct trace_array *tr = iter->tr; |
4663 | ||
15693458 SRRH |
4664 | /* Iterators are static, they should be filled or empty */ |
4665 | if (trace_buffer_iter(iter, iter->cpu_file)) | |
4666 | return POLLIN | POLLRDNORM; | |
2a2cc8f7 | 4667 | |
983f938a | 4668 | if (tr->trace_flags & TRACE_ITER_BLOCK) |
2a2cc8f7 SSP |
4669 | /* |
4670 | * Always select as readable when in blocking mode | |
4671 | */ | |
4672 | return POLLIN | POLLRDNORM; | |
15693458 | 4673 | else |
12883efb | 4674 | return ring_buffer_poll_wait(iter->trace_buffer->buffer, iter->cpu_file, |
15693458 | 4675 | filp, poll_table); |
2a2cc8f7 | 4676 | } |
2a2cc8f7 | 4677 | |
cc60cdc9 SR |
4678 | static unsigned int |
4679 | tracing_poll_pipe(struct file *filp, poll_table *poll_table) | |
4680 | { | |
4681 | struct trace_iterator *iter = filp->private_data; | |
4682 | ||
4683 | return trace_poll(iter, filp, poll_table); | |
2a2cc8f7 SSP |
4684 | } |
4685 | ||
d716ff71 | 4686 | /* Must be called with iter->mutex held. */ |
ff98781b | 4687 | static int tracing_wait_pipe(struct file *filp) |
b3806b43 SR |
4688 | { |
4689 | struct trace_iterator *iter = filp->private_data; | |
8b8b3683 | 4690 | int ret; |
b3806b43 | 4691 | |
b3806b43 | 4692 | while (trace_empty(iter)) { |
2dc8f095 | 4693 | |
107bad8b | 4694 | if ((filp->f_flags & O_NONBLOCK)) { |
ff98781b | 4695 | return -EAGAIN; |
107bad8b | 4696 | } |
2dc8f095 | 4697 | |
b3806b43 | 4698 | /* |
250bfd3d | 4699 | * We block until we read something and tracing is disabled. |
b3806b43 SR |
4700 | * We still block if tracing is disabled, but we have never |
4701 | * read anything. This allows a user to cat this file, and | |
4702 | * then enable tracing. But after we have read something, | |
4703 | * we give an EOF when tracing is again disabled. | |
4704 | * | |
4705 | * iter->pos will be 0 if we haven't read anything. | |
4706 | */ | |
10246fa3 | 4707 | if (!tracing_is_on() && iter->pos) |
b3806b43 | 4708 | break; |
f4874261 SRRH |
4709 | |
4710 | mutex_unlock(&iter->mutex); | |
4711 | ||
e30f53aa | 4712 | ret = wait_on_pipe(iter, false); |
f4874261 SRRH |
4713 | |
4714 | mutex_lock(&iter->mutex); | |
4715 | ||
8b8b3683 SRRH |
4716 | if (ret) |
4717 | return ret; | |
b3806b43 SR |
4718 | } |
4719 | ||
ff98781b EGM |
4720 | return 1; |
4721 | } | |
4722 | ||
4723 | /* | |
4724 | * Consumer reader. | |
4725 | */ | |
4726 | static ssize_t | |
4727 | tracing_read_pipe(struct file *filp, char __user *ubuf, | |
4728 | size_t cnt, loff_t *ppos) | |
4729 | { | |
4730 | struct trace_iterator *iter = filp->private_data; | |
4731 | ssize_t sret; | |
4732 | ||
4733 | /* return any leftover data */ | |
4734 | sret = trace_seq_to_user(&iter->seq, ubuf, cnt); | |
4735 | if (sret != -EBUSY) | |
4736 | return sret; | |
4737 | ||
f9520750 | 4738 | trace_seq_init(&iter->seq); |
ff98781b | 4739 | |
d7350c3f FW |
4740 | /* |
4741 | * Avoid more than one consumer on a single file descriptor | |
4742 | * This is just a matter of traces coherency, the ring buffer itself | |
4743 | * is protected. | |
4744 | */ | |
4745 | mutex_lock(&iter->mutex); | |
ff98781b EGM |
4746 | if (iter->trace->read) { |
4747 | sret = iter->trace->read(iter, filp, ubuf, cnt, ppos); | |
4748 | if (sret) | |
4749 | goto out; | |
4750 | } | |
4751 | ||
4752 | waitagain: | |
4753 | sret = tracing_wait_pipe(filp); | |
4754 | if (sret <= 0) | |
4755 | goto out; | |
4756 | ||
b3806b43 | 4757 | /* stop when tracing is finished */ |
ff98781b EGM |
4758 | if (trace_empty(iter)) { |
4759 | sret = 0; | |
107bad8b | 4760 | goto out; |
ff98781b | 4761 | } |
b3806b43 SR |
4762 | |
4763 | if (cnt >= PAGE_SIZE) | |
4764 | cnt = PAGE_SIZE - 1; | |
4765 | ||
53d0aa77 | 4766 | /* reset all but tr, trace, and overruns */ |
53d0aa77 SR |
4767 | memset(&iter->seq, 0, |
4768 | sizeof(struct trace_iterator) - | |
4769 | offsetof(struct trace_iterator, seq)); | |
ed5467da | 4770 | cpumask_clear(iter->started); |
4823ed7e | 4771 | iter->pos = -1; |
b3806b43 | 4772 | |
4f535968 | 4773 | trace_event_read_lock(); |
7e53bd42 | 4774 | trace_access_lock(iter->cpu_file); |
955b61e5 | 4775 | while (trace_find_next_entry_inc(iter) != NULL) { |
2c4f035f | 4776 | enum print_line_t ret; |
5ac48378 | 4777 | int save_len = iter->seq.seq.len; |
088b1e42 | 4778 | |
f9896bf3 | 4779 | ret = print_trace_line(iter); |
2c4f035f | 4780 | if (ret == TRACE_TYPE_PARTIAL_LINE) { |
088b1e42 | 4781 | /* don't print partial lines */ |
5ac48378 | 4782 | iter->seq.seq.len = save_len; |
b3806b43 | 4783 | break; |
088b1e42 | 4784 | } |
b91facc3 FW |
4785 | if (ret != TRACE_TYPE_NO_CONSUME) |
4786 | trace_consume(iter); | |
b3806b43 | 4787 | |
5ac48378 | 4788 | if (trace_seq_used(&iter->seq) >= cnt) |
b3806b43 | 4789 | break; |
ee5e51f5 JO |
4790 | |
4791 | /* | |
4792 | * Setting the full flag means we reached the trace_seq buffer | |
4793 | * size and we should leave by partial output condition above. | |
4794 | * One of the trace_seq_* functions is not used properly. | |
4795 | */ | |
4796 | WARN_ONCE(iter->seq.full, "full flag set for trace type %d", | |
4797 | iter->ent->type); | |
b3806b43 | 4798 | } |
7e53bd42 | 4799 | trace_access_unlock(iter->cpu_file); |
4f535968 | 4800 | trace_event_read_unlock(); |
b3806b43 | 4801 | |
b3806b43 | 4802 | /* Now copy what we have to the user */ |
6c6c2796 | 4803 | sret = trace_seq_to_user(&iter->seq, ubuf, cnt); |
5ac48378 | 4804 | if (iter->seq.seq.readpos >= trace_seq_used(&iter->seq)) |
f9520750 | 4805 | trace_seq_init(&iter->seq); |
9ff4b974 PP |
4806 | |
4807 | /* | |
25985edc | 4808 | * If there was nothing to send to user, in spite of consuming trace |
9ff4b974 PP |
4809 | * entries, go back to wait for more entries. |
4810 | */ | |
6c6c2796 | 4811 | if (sret == -EBUSY) |
9ff4b974 | 4812 | goto waitagain; |
b3806b43 | 4813 | |
107bad8b | 4814 | out: |
d7350c3f | 4815 | mutex_unlock(&iter->mutex); |
107bad8b | 4816 | |
6c6c2796 | 4817 | return sret; |
b3806b43 SR |
4818 | } |
4819 | ||
3c56819b EGM |
4820 | static void tracing_spd_release_pipe(struct splice_pipe_desc *spd, |
4821 | unsigned int idx) | |
4822 | { | |
4823 | __free_page(spd->pages[idx]); | |
4824 | } | |
4825 | ||
28dfef8f | 4826 | static const struct pipe_buf_operations tracing_pipe_buf_ops = { |
34cd4998 | 4827 | .can_merge = 0, |
34cd4998 | 4828 | .confirm = generic_pipe_buf_confirm, |
92fdd98c | 4829 | .release = generic_pipe_buf_release, |
34cd4998 SR |
4830 | .steal = generic_pipe_buf_steal, |
4831 | .get = generic_pipe_buf_get, | |
3c56819b EGM |
4832 | }; |
4833 | ||
34cd4998 | 4834 | static size_t |
fa7c7f6e | 4835 | tracing_fill_pipe_page(size_t rem, struct trace_iterator *iter) |
34cd4998 SR |
4836 | { |
4837 | size_t count; | |
74f06bb7 | 4838 | int save_len; |
34cd4998 SR |
4839 | int ret; |
4840 | ||
4841 | /* Seq buffer is page-sized, exactly what we need. */ | |
4842 | for (;;) { | |
74f06bb7 | 4843 | save_len = iter->seq.seq.len; |
34cd4998 | 4844 | ret = print_trace_line(iter); |
74f06bb7 SRRH |
4845 | |
4846 | if (trace_seq_has_overflowed(&iter->seq)) { | |
4847 | iter->seq.seq.len = save_len; | |
34cd4998 SR |
4848 | break; |
4849 | } | |
74f06bb7 SRRH |
4850 | |
4851 | /* | |
4852 | * This should not be hit, because it should only | |
4853 | * be set if the iter->seq overflowed. But check it | |
4854 | * anyway to be safe. | |
4855 | */ | |
34cd4998 | 4856 | if (ret == TRACE_TYPE_PARTIAL_LINE) { |
74f06bb7 SRRH |
4857 | iter->seq.seq.len = save_len; |
4858 | break; | |
4859 | } | |
4860 | ||
5ac48378 | 4861 | count = trace_seq_used(&iter->seq) - save_len; |
74f06bb7 SRRH |
4862 | if (rem < count) { |
4863 | rem = 0; | |
4864 | iter->seq.seq.len = save_len; | |
34cd4998 SR |
4865 | break; |
4866 | } | |
4867 | ||
74e7ff8c LJ |
4868 | if (ret != TRACE_TYPE_NO_CONSUME) |
4869 | trace_consume(iter); | |
34cd4998 | 4870 | rem -= count; |
955b61e5 | 4871 | if (!trace_find_next_entry_inc(iter)) { |
34cd4998 SR |
4872 | rem = 0; |
4873 | iter->ent = NULL; | |
4874 | break; | |
4875 | } | |
4876 | } | |
4877 | ||
4878 | return rem; | |
4879 | } | |
4880 | ||
3c56819b EGM |
4881 | static ssize_t tracing_splice_read_pipe(struct file *filp, |
4882 | loff_t *ppos, | |
4883 | struct pipe_inode_info *pipe, | |
4884 | size_t len, | |
4885 | unsigned int flags) | |
4886 | { | |
35f3d14d JA |
4887 | struct page *pages_def[PIPE_DEF_BUFFERS]; |
4888 | struct partial_page partial_def[PIPE_DEF_BUFFERS]; | |
3c56819b EGM |
4889 | struct trace_iterator *iter = filp->private_data; |
4890 | struct splice_pipe_desc spd = { | |
35f3d14d JA |
4891 | .pages = pages_def, |
4892 | .partial = partial_def, | |
34cd4998 | 4893 | .nr_pages = 0, /* This gets updated below. */ |
047fe360 | 4894 | .nr_pages_max = PIPE_DEF_BUFFERS, |
34cd4998 SR |
4895 | .flags = flags, |
4896 | .ops = &tracing_pipe_buf_ops, | |
4897 | .spd_release = tracing_spd_release_pipe, | |
3c56819b EGM |
4898 | }; |
4899 | ssize_t ret; | |
34cd4998 | 4900 | size_t rem; |
3c56819b EGM |
4901 | unsigned int i; |
4902 | ||
35f3d14d JA |
4903 | if (splice_grow_spd(pipe, &spd)) |
4904 | return -ENOMEM; | |
4905 | ||
d7350c3f | 4906 | mutex_lock(&iter->mutex); |
3c56819b EGM |
4907 | |
4908 | if (iter->trace->splice_read) { | |
4909 | ret = iter->trace->splice_read(iter, filp, | |
4910 | ppos, pipe, len, flags); | |
4911 | if (ret) | |
34cd4998 | 4912 | goto out_err; |
3c56819b EGM |
4913 | } |
4914 | ||
4915 | ret = tracing_wait_pipe(filp); | |
4916 | if (ret <= 0) | |
34cd4998 | 4917 | goto out_err; |
3c56819b | 4918 | |
955b61e5 | 4919 | if (!iter->ent && !trace_find_next_entry_inc(iter)) { |
3c56819b | 4920 | ret = -EFAULT; |
34cd4998 | 4921 | goto out_err; |
3c56819b EGM |
4922 | } |
4923 | ||
4f535968 | 4924 | trace_event_read_lock(); |
7e53bd42 | 4925 | trace_access_lock(iter->cpu_file); |
4f535968 | 4926 | |
3c56819b | 4927 | /* Fill as many pages as possible. */ |
a786c06d | 4928 | for (i = 0, rem = len; i < spd.nr_pages_max && rem; i++) { |
35f3d14d JA |
4929 | spd.pages[i] = alloc_page(GFP_KERNEL); |
4930 | if (!spd.pages[i]) | |
34cd4998 | 4931 | break; |
3c56819b | 4932 | |
fa7c7f6e | 4933 | rem = tracing_fill_pipe_page(rem, iter); |
3c56819b EGM |
4934 | |
4935 | /* Copy the data into the page, so we can start over. */ | |
4936 | ret = trace_seq_to_buffer(&iter->seq, | |
35f3d14d | 4937 | page_address(spd.pages[i]), |
5ac48378 | 4938 | trace_seq_used(&iter->seq)); |
3c56819b | 4939 | if (ret < 0) { |
35f3d14d | 4940 | __free_page(spd.pages[i]); |
3c56819b EGM |
4941 | break; |
4942 | } | |
35f3d14d | 4943 | spd.partial[i].offset = 0; |
5ac48378 | 4944 | spd.partial[i].len = trace_seq_used(&iter->seq); |
3c56819b | 4945 | |
f9520750 | 4946 | trace_seq_init(&iter->seq); |
3c56819b EGM |
4947 | } |
4948 | ||
7e53bd42 | 4949 | trace_access_unlock(iter->cpu_file); |
4f535968 | 4950 | trace_event_read_unlock(); |
d7350c3f | 4951 | mutex_unlock(&iter->mutex); |
3c56819b EGM |
4952 | |
4953 | spd.nr_pages = i; | |
4954 | ||
35f3d14d JA |
4955 | ret = splice_to_pipe(pipe, &spd); |
4956 | out: | |
047fe360 | 4957 | splice_shrink_spd(&spd); |
35f3d14d | 4958 | return ret; |
3c56819b | 4959 | |
34cd4998 | 4960 | out_err: |
d7350c3f | 4961 | mutex_unlock(&iter->mutex); |
35f3d14d | 4962 | goto out; |
3c56819b EGM |
4963 | } |
4964 | ||
a98a3c3f SR |
4965 | static ssize_t |
4966 | tracing_entries_read(struct file *filp, char __user *ubuf, | |
4967 | size_t cnt, loff_t *ppos) | |
4968 | { | |
0bc392ee ON |
4969 | struct inode *inode = file_inode(filp); |
4970 | struct trace_array *tr = inode->i_private; | |
4971 | int cpu = tracing_get_cpu(inode); | |
438ced17 VN |
4972 | char buf[64]; |
4973 | int r = 0; | |
4974 | ssize_t ret; | |
a98a3c3f | 4975 | |
db526ca3 | 4976 | mutex_lock(&trace_types_lock); |
438ced17 | 4977 | |
0bc392ee | 4978 | if (cpu == RING_BUFFER_ALL_CPUS) { |
438ced17 VN |
4979 | int cpu, buf_size_same; |
4980 | unsigned long size; | |
4981 | ||
4982 | size = 0; | |
4983 | buf_size_same = 1; | |
4984 | /* check if all cpu sizes are same */ | |
4985 | for_each_tracing_cpu(cpu) { | |
4986 | /* fill in the size from first enabled cpu */ | |
4987 | if (size == 0) | |
12883efb SRRH |
4988 | size = per_cpu_ptr(tr->trace_buffer.data, cpu)->entries; |
4989 | if (size != per_cpu_ptr(tr->trace_buffer.data, cpu)->entries) { | |
438ced17 VN |
4990 | buf_size_same = 0; |
4991 | break; | |
4992 | } | |
4993 | } | |
4994 | ||
4995 | if (buf_size_same) { | |
4996 | if (!ring_buffer_expanded) | |
4997 | r = sprintf(buf, "%lu (expanded: %lu)\n", | |
4998 | size >> 10, | |
4999 | trace_buf_size >> 10); | |
5000 | else | |
5001 | r = sprintf(buf, "%lu\n", size >> 10); | |
5002 | } else | |
5003 | r = sprintf(buf, "X\n"); | |
5004 | } else | |
0bc392ee | 5005 | r = sprintf(buf, "%lu\n", per_cpu_ptr(tr->trace_buffer.data, cpu)->entries >> 10); |
438ced17 | 5006 | |
db526ca3 SR |
5007 | mutex_unlock(&trace_types_lock); |
5008 | ||
438ced17 VN |
5009 | ret = simple_read_from_buffer(ubuf, cnt, ppos, buf, r); |
5010 | return ret; | |
a98a3c3f SR |
5011 | } |
5012 | ||
5013 | static ssize_t | |
5014 | tracing_entries_write(struct file *filp, const char __user *ubuf, | |
5015 | size_t cnt, loff_t *ppos) | |
5016 | { | |
0bc392ee ON |
5017 | struct inode *inode = file_inode(filp); |
5018 | struct trace_array *tr = inode->i_private; | |
a98a3c3f | 5019 | unsigned long val; |
4f271a2a | 5020 | int ret; |
a98a3c3f | 5021 | |
22fe9b54 PH |
5022 | ret = kstrtoul_from_user(ubuf, cnt, 10, &val); |
5023 | if (ret) | |
c6caeeb1 | 5024 | return ret; |
a98a3c3f SR |
5025 | |
5026 | /* must have at least 1 entry */ | |
5027 | if (!val) | |
5028 | return -EINVAL; | |
5029 | ||
1696b2b0 SR |
5030 | /* value is in KB */ |
5031 | val <<= 10; | |
0bc392ee | 5032 | ret = tracing_resize_ring_buffer(tr, val, tracing_get_cpu(inode)); |
4f271a2a VN |
5033 | if (ret < 0) |
5034 | return ret; | |
a98a3c3f | 5035 | |
cf8517cf | 5036 | *ppos += cnt; |
a98a3c3f | 5037 | |
4f271a2a VN |
5038 | return cnt; |
5039 | } | |
bf5e6519 | 5040 | |
f81ab074 VN |
5041 | static ssize_t |
5042 | tracing_total_entries_read(struct file *filp, char __user *ubuf, | |
5043 | size_t cnt, loff_t *ppos) | |
5044 | { | |
5045 | struct trace_array *tr = filp->private_data; | |
5046 | char buf[64]; | |
5047 | int r, cpu; | |
5048 | unsigned long size = 0, expanded_size = 0; | |
5049 | ||
5050 | mutex_lock(&trace_types_lock); | |
5051 | for_each_tracing_cpu(cpu) { | |
12883efb | 5052 | size += per_cpu_ptr(tr->trace_buffer.data, cpu)->entries >> 10; |
f81ab074 VN |
5053 | if (!ring_buffer_expanded) |
5054 | expanded_size += trace_buf_size >> 10; | |
5055 | } | |
5056 | if (ring_buffer_expanded) | |
5057 | r = sprintf(buf, "%lu\n", size); | |
5058 | else | |
5059 | r = sprintf(buf, "%lu (expanded: %lu)\n", size, expanded_size); | |
5060 | mutex_unlock(&trace_types_lock); | |
5061 | ||
5062 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, r); | |
5063 | } | |
5064 | ||
4f271a2a VN |
5065 | static ssize_t |
5066 | tracing_free_buffer_write(struct file *filp, const char __user *ubuf, | |
5067 | size_t cnt, loff_t *ppos) | |
5068 | { | |
5069 | /* | |
5070 | * There is no need to read what the user has written, this function | |
5071 | * is just to make sure that there is no error when "echo" is used | |
5072 | */ | |
5073 | ||
5074 | *ppos += cnt; | |
a98a3c3f SR |
5075 | |
5076 | return cnt; | |
5077 | } | |
5078 | ||
4f271a2a VN |
5079 | static int |
5080 | tracing_free_buffer_release(struct inode *inode, struct file *filp) | |
5081 | { | |
2b6080f2 SR |
5082 | struct trace_array *tr = inode->i_private; |
5083 | ||
cf30cf67 | 5084 | /* disable tracing ? */ |
983f938a | 5085 | if (tr->trace_flags & TRACE_ITER_STOP_ON_FREE) |
711e1243 | 5086 | tracer_tracing_off(tr); |
4f271a2a | 5087 | /* resize the ring buffer to 0 */ |
2b6080f2 | 5088 | tracing_resize_ring_buffer(tr, 0, RING_BUFFER_ALL_CPUS); |
4f271a2a | 5089 | |
7b85af63 SRRH |
5090 | trace_array_put(tr); |
5091 | ||
4f271a2a VN |
5092 | return 0; |
5093 | } | |
5094 | ||
5bf9a1ee PP |
5095 | static ssize_t |
5096 | tracing_mark_write(struct file *filp, const char __user *ubuf, | |
5097 | size_t cnt, loff_t *fpos) | |
5098 | { | |
d696b58c | 5099 | unsigned long addr = (unsigned long)ubuf; |
2d71619c | 5100 | struct trace_array *tr = filp->private_data; |
d696b58c SR |
5101 | struct ring_buffer_event *event; |
5102 | struct ring_buffer *buffer; | |
5103 | struct print_entry *entry; | |
5104 | unsigned long irq_flags; | |
5105 | struct page *pages[2]; | |
6edb2a8a | 5106 | void *map_page[2]; |
d696b58c SR |
5107 | int nr_pages = 1; |
5108 | ssize_t written; | |
d696b58c SR |
5109 | int offset; |
5110 | int size; | |
5111 | int len; | |
5112 | int ret; | |
6edb2a8a | 5113 | int i; |
5bf9a1ee | 5114 | |
c76f0694 | 5115 | if (tracing_disabled) |
5bf9a1ee PP |
5116 | return -EINVAL; |
5117 | ||
983f938a | 5118 | if (!(tr->trace_flags & TRACE_ITER_MARKERS)) |
5224c3a3 MSB |
5119 | return -EINVAL; |
5120 | ||
5bf9a1ee PP |
5121 | if (cnt > TRACE_BUF_SIZE) |
5122 | cnt = TRACE_BUF_SIZE; | |
5123 | ||
d696b58c SR |
5124 | /* |
5125 | * Userspace is injecting traces into the kernel trace buffer. | |
5126 | * We want to be as non intrusive as possible. | |
5127 | * To do so, we do not want to allocate any special buffers | |
5128 | * or take any locks, but instead write the userspace data | |
5129 | * straight into the ring buffer. | |
5130 | * | |
5131 | * First we need to pin the userspace buffer into memory, | |
5132 | * which, most likely it is, because it just referenced it. | |
5133 | * But there's no guarantee that it is. By using get_user_pages_fast() | |
5134 | * and kmap_atomic/kunmap_atomic() we can get access to the | |
5135 | * pages directly. We then write the data directly into the | |
5136 | * ring buffer. | |
5137 | */ | |
5138 | BUILD_BUG_ON(TRACE_BUF_SIZE >= PAGE_SIZE); | |
5bf9a1ee | 5139 | |
d696b58c SR |
5140 | /* check if we cross pages */ |
5141 | if ((addr & PAGE_MASK) != ((addr + cnt) & PAGE_MASK)) | |
5142 | nr_pages = 2; | |
5143 | ||
5144 | offset = addr & (PAGE_SIZE - 1); | |
5145 | addr &= PAGE_MASK; | |
5146 | ||
5147 | ret = get_user_pages_fast(addr, nr_pages, 0, pages); | |
5148 | if (ret < nr_pages) { | |
5149 | while (--ret >= 0) | |
5150 | put_page(pages[ret]); | |
5151 | written = -EFAULT; | |
5152 | goto out; | |
5bf9a1ee | 5153 | } |
d696b58c | 5154 | |
6edb2a8a SR |
5155 | for (i = 0; i < nr_pages; i++) |
5156 | map_page[i] = kmap_atomic(pages[i]); | |
d696b58c SR |
5157 | |
5158 | local_save_flags(irq_flags); | |
5159 | size = sizeof(*entry) + cnt + 2; /* possible \n added */ | |
2d71619c | 5160 | buffer = tr->trace_buffer.buffer; |
d696b58c SR |
5161 | event = trace_buffer_lock_reserve(buffer, TRACE_PRINT, size, |
5162 | irq_flags, preempt_count()); | |
5163 | if (!event) { | |
5164 | /* Ring buffer disabled, return as if not open for write */ | |
5165 | written = -EBADF; | |
5166 | goto out_unlock; | |
5bf9a1ee | 5167 | } |
d696b58c SR |
5168 | |
5169 | entry = ring_buffer_event_data(event); | |
5170 | entry->ip = _THIS_IP_; | |
5171 | ||
5172 | if (nr_pages == 2) { | |
5173 | len = PAGE_SIZE - offset; | |
6edb2a8a SR |
5174 | memcpy(&entry->buf, map_page[0] + offset, len); |
5175 | memcpy(&entry->buf[len], map_page[1], cnt - len); | |
c13d2f7c | 5176 | } else |
6edb2a8a | 5177 | memcpy(&entry->buf, map_page[0] + offset, cnt); |
5bf9a1ee | 5178 | |
d696b58c SR |
5179 | if (entry->buf[cnt - 1] != '\n') { |
5180 | entry->buf[cnt] = '\n'; | |
5181 | entry->buf[cnt + 1] = '\0'; | |
5182 | } else | |
5183 | entry->buf[cnt] = '\0'; | |
5184 | ||
7ffbd48d | 5185 | __buffer_unlock_commit(buffer, event); |
5bf9a1ee | 5186 | |
d696b58c | 5187 | written = cnt; |
5bf9a1ee | 5188 | |
d696b58c | 5189 | *fpos += written; |
1aa54bca | 5190 | |
d696b58c | 5191 | out_unlock: |
7215853e | 5192 | for (i = nr_pages - 1; i >= 0; i--) { |
6edb2a8a SR |
5193 | kunmap_atomic(map_page[i]); |
5194 | put_page(pages[i]); | |
5195 | } | |
d696b58c | 5196 | out: |
1aa54bca | 5197 | return written; |
5bf9a1ee PP |
5198 | } |
5199 | ||
13f16d20 | 5200 | static int tracing_clock_show(struct seq_file *m, void *v) |
5079f326 | 5201 | { |
2b6080f2 | 5202 | struct trace_array *tr = m->private; |
5079f326 Z |
5203 | int i; |
5204 | ||
5205 | for (i = 0; i < ARRAY_SIZE(trace_clocks); i++) | |
13f16d20 | 5206 | seq_printf(m, |
5079f326 | 5207 | "%s%s%s%s", i ? " " : "", |
2b6080f2 SR |
5208 | i == tr->clock_id ? "[" : "", trace_clocks[i].name, |
5209 | i == tr->clock_id ? "]" : ""); | |
13f16d20 | 5210 | seq_putc(m, '\n'); |
5079f326 | 5211 | |
13f16d20 | 5212 | return 0; |
5079f326 Z |
5213 | } |
5214 | ||
e1e232ca | 5215 | static int tracing_set_clock(struct trace_array *tr, const char *clockstr) |
5079f326 | 5216 | { |
5079f326 Z |
5217 | int i; |
5218 | ||
5079f326 Z |
5219 | for (i = 0; i < ARRAY_SIZE(trace_clocks); i++) { |
5220 | if (strcmp(trace_clocks[i].name, clockstr) == 0) | |
5221 | break; | |
5222 | } | |
5223 | if (i == ARRAY_SIZE(trace_clocks)) | |
5224 | return -EINVAL; | |
5225 | ||
5079f326 Z |
5226 | mutex_lock(&trace_types_lock); |
5227 | ||
2b6080f2 SR |
5228 | tr->clock_id = i; |
5229 | ||
12883efb | 5230 | ring_buffer_set_clock(tr->trace_buffer.buffer, trace_clocks[i].func); |
5079f326 | 5231 | |
60303ed3 DS |
5232 | /* |
5233 | * New clock may not be consistent with the previous clock. | |
5234 | * Reset the buffer so that it doesn't have incomparable timestamps. | |
5235 | */ | |
9457158b | 5236 | tracing_reset_online_cpus(&tr->trace_buffer); |
12883efb SRRH |
5237 | |
5238 | #ifdef CONFIG_TRACER_MAX_TRACE | |
5239 | if (tr->flags & TRACE_ARRAY_FL_GLOBAL && tr->max_buffer.buffer) | |
5240 | ring_buffer_set_clock(tr->max_buffer.buffer, trace_clocks[i].func); | |
9457158b | 5241 | tracing_reset_online_cpus(&tr->max_buffer); |
12883efb | 5242 | #endif |
60303ed3 | 5243 | |
5079f326 Z |
5244 | mutex_unlock(&trace_types_lock); |
5245 | ||
e1e232ca SR |
5246 | return 0; |
5247 | } | |
5248 | ||
5249 | static ssize_t tracing_clock_write(struct file *filp, const char __user *ubuf, | |
5250 | size_t cnt, loff_t *fpos) | |
5251 | { | |
5252 | struct seq_file *m = filp->private_data; | |
5253 | struct trace_array *tr = m->private; | |
5254 | char buf[64]; | |
5255 | const char *clockstr; | |
5256 | int ret; | |
5257 | ||
5258 | if (cnt >= sizeof(buf)) | |
5259 | return -EINVAL; | |
5260 | ||
5261 | if (copy_from_user(&buf, ubuf, cnt)) | |
5262 | return -EFAULT; | |
5263 | ||
5264 | buf[cnt] = 0; | |
5265 | ||
5266 | clockstr = strstrip(buf); | |
5267 | ||
5268 | ret = tracing_set_clock(tr, clockstr); | |
5269 | if (ret) | |
5270 | return ret; | |
5271 | ||
5079f326 Z |
5272 | *fpos += cnt; |
5273 | ||
5274 | return cnt; | |
5275 | } | |
5276 | ||
13f16d20 LZ |
5277 | static int tracing_clock_open(struct inode *inode, struct file *file) |
5278 | { | |
7b85af63 SRRH |
5279 | struct trace_array *tr = inode->i_private; |
5280 | int ret; | |
5281 | ||
13f16d20 LZ |
5282 | if (tracing_disabled) |
5283 | return -ENODEV; | |
2b6080f2 | 5284 | |
7b85af63 SRRH |
5285 | if (trace_array_get(tr)) |
5286 | return -ENODEV; | |
5287 | ||
5288 | ret = single_open(file, tracing_clock_show, inode->i_private); | |
5289 | if (ret < 0) | |
5290 | trace_array_put(tr); | |
5291 | ||
5292 | return ret; | |
13f16d20 LZ |
5293 | } |
5294 | ||
6de58e62 SRRH |
5295 | struct ftrace_buffer_info { |
5296 | struct trace_iterator iter; | |
5297 | void *spare; | |
5298 | unsigned int read; | |
5299 | }; | |
5300 | ||
debdd57f HT |
5301 | #ifdef CONFIG_TRACER_SNAPSHOT |
5302 | static int tracing_snapshot_open(struct inode *inode, struct file *file) | |
5303 | { | |
6484c71c | 5304 | struct trace_array *tr = inode->i_private; |
debdd57f | 5305 | struct trace_iterator *iter; |
2b6080f2 | 5306 | struct seq_file *m; |
debdd57f HT |
5307 | int ret = 0; |
5308 | ||
ff451961 SRRH |
5309 | if (trace_array_get(tr) < 0) |
5310 | return -ENODEV; | |
5311 | ||
debdd57f | 5312 | if (file->f_mode & FMODE_READ) { |
6484c71c | 5313 | iter = __tracing_open(inode, file, true); |
debdd57f HT |
5314 | if (IS_ERR(iter)) |
5315 | ret = PTR_ERR(iter); | |
2b6080f2 SR |
5316 | } else { |
5317 | /* Writes still need the seq_file to hold the private data */ | |
f77d09a3 | 5318 | ret = -ENOMEM; |
2b6080f2 SR |
5319 | m = kzalloc(sizeof(*m), GFP_KERNEL); |
5320 | if (!m) | |
f77d09a3 | 5321 | goto out; |
2b6080f2 SR |
5322 | iter = kzalloc(sizeof(*iter), GFP_KERNEL); |
5323 | if (!iter) { | |
5324 | kfree(m); | |
f77d09a3 | 5325 | goto out; |
2b6080f2 | 5326 | } |
f77d09a3 AL |
5327 | ret = 0; |
5328 | ||
ff451961 | 5329 | iter->tr = tr; |
6484c71c ON |
5330 | iter->trace_buffer = &tr->max_buffer; |
5331 | iter->cpu_file = tracing_get_cpu(inode); | |
2b6080f2 SR |
5332 | m->private = iter; |
5333 | file->private_data = m; | |
debdd57f | 5334 | } |
f77d09a3 | 5335 | out: |
ff451961 SRRH |
5336 | if (ret < 0) |
5337 | trace_array_put(tr); | |
5338 | ||
debdd57f HT |
5339 | return ret; |
5340 | } | |
5341 | ||
5342 | static ssize_t | |
5343 | tracing_snapshot_write(struct file *filp, const char __user *ubuf, size_t cnt, | |
5344 | loff_t *ppos) | |
5345 | { | |
2b6080f2 SR |
5346 | struct seq_file *m = filp->private_data; |
5347 | struct trace_iterator *iter = m->private; | |
5348 | struct trace_array *tr = iter->tr; | |
debdd57f HT |
5349 | unsigned long val; |
5350 | int ret; | |
5351 | ||
5352 | ret = tracing_update_buffers(); | |
5353 | if (ret < 0) | |
5354 | return ret; | |
5355 | ||
5356 | ret = kstrtoul_from_user(ubuf, cnt, 10, &val); | |
5357 | if (ret) | |
5358 | return ret; | |
5359 | ||
5360 | mutex_lock(&trace_types_lock); | |
5361 | ||
2b6080f2 | 5362 | if (tr->current_trace->use_max_tr) { |
debdd57f HT |
5363 | ret = -EBUSY; |
5364 | goto out; | |
5365 | } | |
5366 | ||
5367 | switch (val) { | |
5368 | case 0: | |
f1affcaa SRRH |
5369 | if (iter->cpu_file != RING_BUFFER_ALL_CPUS) { |
5370 | ret = -EINVAL; | |
5371 | break; | |
debdd57f | 5372 | } |
3209cff4 SRRH |
5373 | if (tr->allocated_snapshot) |
5374 | free_snapshot(tr); | |
debdd57f HT |
5375 | break; |
5376 | case 1: | |
f1affcaa SRRH |
5377 | /* Only allow per-cpu swap if the ring buffer supports it */ |
5378 | #ifndef CONFIG_RING_BUFFER_ALLOW_SWAP | |
5379 | if (iter->cpu_file != RING_BUFFER_ALL_CPUS) { | |
5380 | ret = -EINVAL; | |
5381 | break; | |
5382 | } | |
5383 | #endif | |
45ad21ca | 5384 | if (!tr->allocated_snapshot) { |
3209cff4 | 5385 | ret = alloc_snapshot(tr); |
debdd57f HT |
5386 | if (ret < 0) |
5387 | break; | |
debdd57f | 5388 | } |
debdd57f HT |
5389 | local_irq_disable(); |
5390 | /* Now, we're going to swap */ | |
f1affcaa | 5391 | if (iter->cpu_file == RING_BUFFER_ALL_CPUS) |
ce9bae55 | 5392 | update_max_tr(tr, current, smp_processor_id()); |
f1affcaa | 5393 | else |
ce9bae55 | 5394 | update_max_tr_single(tr, current, iter->cpu_file); |
debdd57f HT |
5395 | local_irq_enable(); |
5396 | break; | |
5397 | default: | |
45ad21ca | 5398 | if (tr->allocated_snapshot) { |
f1affcaa SRRH |
5399 | if (iter->cpu_file == RING_BUFFER_ALL_CPUS) |
5400 | tracing_reset_online_cpus(&tr->max_buffer); | |
5401 | else | |
5402 | tracing_reset(&tr->max_buffer, iter->cpu_file); | |
5403 | } | |
debdd57f HT |
5404 | break; |
5405 | } | |
5406 | ||
5407 | if (ret >= 0) { | |
5408 | *ppos += cnt; | |
5409 | ret = cnt; | |
5410 | } | |
5411 | out: | |
5412 | mutex_unlock(&trace_types_lock); | |
5413 | return ret; | |
5414 | } | |
2b6080f2 SR |
5415 | |
5416 | static int tracing_snapshot_release(struct inode *inode, struct file *file) | |
5417 | { | |
5418 | struct seq_file *m = file->private_data; | |
ff451961 SRRH |
5419 | int ret; |
5420 | ||
5421 | ret = tracing_release(inode, file); | |
2b6080f2 SR |
5422 | |
5423 | if (file->f_mode & FMODE_READ) | |
ff451961 | 5424 | return ret; |
2b6080f2 SR |
5425 | |
5426 | /* If write only, the seq_file is just a stub */ | |
5427 | if (m) | |
5428 | kfree(m->private); | |
5429 | kfree(m); | |
5430 | ||
5431 | return 0; | |
5432 | } | |
5433 | ||
6de58e62 SRRH |
5434 | static int tracing_buffers_open(struct inode *inode, struct file *filp); |
5435 | static ssize_t tracing_buffers_read(struct file *filp, char __user *ubuf, | |
5436 | size_t count, loff_t *ppos); | |
5437 | static int tracing_buffers_release(struct inode *inode, struct file *file); | |
5438 | static ssize_t tracing_buffers_splice_read(struct file *file, loff_t *ppos, | |
5439 | struct pipe_inode_info *pipe, size_t len, unsigned int flags); | |
5440 | ||
5441 | static int snapshot_raw_open(struct inode *inode, struct file *filp) | |
5442 | { | |
5443 | struct ftrace_buffer_info *info; | |
5444 | int ret; | |
5445 | ||
5446 | ret = tracing_buffers_open(inode, filp); | |
5447 | if (ret < 0) | |
5448 | return ret; | |
5449 | ||
5450 | info = filp->private_data; | |
5451 | ||
5452 | if (info->iter.trace->use_max_tr) { | |
5453 | tracing_buffers_release(inode, filp); | |
5454 | return -EBUSY; | |
5455 | } | |
5456 | ||
5457 | info->iter.snapshot = true; | |
5458 | info->iter.trace_buffer = &info->iter.tr->max_buffer; | |
5459 | ||
5460 | return ret; | |
5461 | } | |
5462 | ||
debdd57f HT |
5463 | #endif /* CONFIG_TRACER_SNAPSHOT */ |
5464 | ||
5465 | ||
6508fa76 SF |
5466 | static const struct file_operations tracing_thresh_fops = { |
5467 | .open = tracing_open_generic, | |
5468 | .read = tracing_thresh_read, | |
5469 | .write = tracing_thresh_write, | |
5470 | .llseek = generic_file_llseek, | |
5471 | }; | |
5472 | ||
5e2336a0 | 5473 | static const struct file_operations tracing_max_lat_fops = { |
4bf39a94 IM |
5474 | .open = tracing_open_generic, |
5475 | .read = tracing_max_lat_read, | |
5476 | .write = tracing_max_lat_write, | |
b444786f | 5477 | .llseek = generic_file_llseek, |
bc0c38d1 SR |
5478 | }; |
5479 | ||
5e2336a0 | 5480 | static const struct file_operations set_tracer_fops = { |
4bf39a94 IM |
5481 | .open = tracing_open_generic, |
5482 | .read = tracing_set_trace_read, | |
5483 | .write = tracing_set_trace_write, | |
b444786f | 5484 | .llseek = generic_file_llseek, |
bc0c38d1 SR |
5485 | }; |
5486 | ||
5e2336a0 | 5487 | static const struct file_operations tracing_pipe_fops = { |
4bf39a94 | 5488 | .open = tracing_open_pipe, |
2a2cc8f7 | 5489 | .poll = tracing_poll_pipe, |
4bf39a94 | 5490 | .read = tracing_read_pipe, |
3c56819b | 5491 | .splice_read = tracing_splice_read_pipe, |
4bf39a94 | 5492 | .release = tracing_release_pipe, |
b444786f | 5493 | .llseek = no_llseek, |
b3806b43 SR |
5494 | }; |
5495 | ||
5e2336a0 | 5496 | static const struct file_operations tracing_entries_fops = { |
0bc392ee | 5497 | .open = tracing_open_generic_tr, |
a98a3c3f SR |
5498 | .read = tracing_entries_read, |
5499 | .write = tracing_entries_write, | |
b444786f | 5500 | .llseek = generic_file_llseek, |
0bc392ee | 5501 | .release = tracing_release_generic_tr, |
a98a3c3f SR |
5502 | }; |
5503 | ||
f81ab074 | 5504 | static const struct file_operations tracing_total_entries_fops = { |
7b85af63 | 5505 | .open = tracing_open_generic_tr, |
f81ab074 VN |
5506 | .read = tracing_total_entries_read, |
5507 | .llseek = generic_file_llseek, | |
7b85af63 | 5508 | .release = tracing_release_generic_tr, |
f81ab074 VN |
5509 | }; |
5510 | ||
4f271a2a | 5511 | static const struct file_operations tracing_free_buffer_fops = { |
7b85af63 | 5512 | .open = tracing_open_generic_tr, |
4f271a2a VN |
5513 | .write = tracing_free_buffer_write, |
5514 | .release = tracing_free_buffer_release, | |
5515 | }; | |
5516 | ||
5e2336a0 | 5517 | static const struct file_operations tracing_mark_fops = { |
7b85af63 | 5518 | .open = tracing_open_generic_tr, |
5bf9a1ee | 5519 | .write = tracing_mark_write, |
b444786f | 5520 | .llseek = generic_file_llseek, |
7b85af63 | 5521 | .release = tracing_release_generic_tr, |
5bf9a1ee PP |
5522 | }; |
5523 | ||
5079f326 | 5524 | static const struct file_operations trace_clock_fops = { |
13f16d20 LZ |
5525 | .open = tracing_clock_open, |
5526 | .read = seq_read, | |
5527 | .llseek = seq_lseek, | |
7b85af63 | 5528 | .release = tracing_single_release_tr, |
5079f326 Z |
5529 | .write = tracing_clock_write, |
5530 | }; | |
5531 | ||
debdd57f HT |
5532 | #ifdef CONFIG_TRACER_SNAPSHOT |
5533 | static const struct file_operations snapshot_fops = { | |
5534 | .open = tracing_snapshot_open, | |
5535 | .read = seq_read, | |
5536 | .write = tracing_snapshot_write, | |
098c879e | 5537 | .llseek = tracing_lseek, |
2b6080f2 | 5538 | .release = tracing_snapshot_release, |
debdd57f | 5539 | }; |
debdd57f | 5540 | |
6de58e62 SRRH |
5541 | static const struct file_operations snapshot_raw_fops = { |
5542 | .open = snapshot_raw_open, | |
5543 | .read = tracing_buffers_read, | |
5544 | .release = tracing_buffers_release, | |
5545 | .splice_read = tracing_buffers_splice_read, | |
5546 | .llseek = no_llseek, | |
2cadf913 SR |
5547 | }; |
5548 | ||
6de58e62 SRRH |
5549 | #endif /* CONFIG_TRACER_SNAPSHOT */ |
5550 | ||
2cadf913 SR |
5551 | static int tracing_buffers_open(struct inode *inode, struct file *filp) |
5552 | { | |
46ef2be0 | 5553 | struct trace_array *tr = inode->i_private; |
2cadf913 | 5554 | struct ftrace_buffer_info *info; |
7b85af63 | 5555 | int ret; |
2cadf913 SR |
5556 | |
5557 | if (tracing_disabled) | |
5558 | return -ENODEV; | |
5559 | ||
7b85af63 SRRH |
5560 | if (trace_array_get(tr) < 0) |
5561 | return -ENODEV; | |
5562 | ||
2cadf913 | 5563 | info = kzalloc(sizeof(*info), GFP_KERNEL); |
7b85af63 SRRH |
5564 | if (!info) { |
5565 | trace_array_put(tr); | |
2cadf913 | 5566 | return -ENOMEM; |
7b85af63 | 5567 | } |
2cadf913 | 5568 | |
a695cb58 SRRH |
5569 | mutex_lock(&trace_types_lock); |
5570 | ||
cc60cdc9 | 5571 | info->iter.tr = tr; |
46ef2be0 | 5572 | info->iter.cpu_file = tracing_get_cpu(inode); |
b627344f | 5573 | info->iter.trace = tr->current_trace; |
12883efb | 5574 | info->iter.trace_buffer = &tr->trace_buffer; |
cc60cdc9 | 5575 | info->spare = NULL; |
2cadf913 | 5576 | /* Force reading ring buffer for first read */ |
cc60cdc9 | 5577 | info->read = (unsigned int)-1; |
2cadf913 SR |
5578 | |
5579 | filp->private_data = info; | |
5580 | ||
cf6ab6d9 SRRH |
5581 | tr->current_trace->ref++; |
5582 | ||
a695cb58 SRRH |
5583 | mutex_unlock(&trace_types_lock); |
5584 | ||
7b85af63 SRRH |
5585 | ret = nonseekable_open(inode, filp); |
5586 | if (ret < 0) | |
5587 | trace_array_put(tr); | |
5588 | ||
5589 | return ret; | |
2cadf913 SR |
5590 | } |
5591 | ||
cc60cdc9 SR |
5592 | static unsigned int |
5593 | tracing_buffers_poll(struct file *filp, poll_table *poll_table) | |
5594 | { | |
5595 | struct ftrace_buffer_info *info = filp->private_data; | |
5596 | struct trace_iterator *iter = &info->iter; | |
5597 | ||
5598 | return trace_poll(iter, filp, poll_table); | |
5599 | } | |
5600 | ||
2cadf913 SR |
5601 | static ssize_t |
5602 | tracing_buffers_read(struct file *filp, char __user *ubuf, | |
5603 | size_t count, loff_t *ppos) | |
5604 | { | |
5605 | struct ftrace_buffer_info *info = filp->private_data; | |
cc60cdc9 | 5606 | struct trace_iterator *iter = &info->iter; |
2cadf913 | 5607 | ssize_t ret; |
6de58e62 | 5608 | ssize_t size; |
2cadf913 | 5609 | |
2dc5d12b SR |
5610 | if (!count) |
5611 | return 0; | |
5612 | ||
6de58e62 | 5613 | #ifdef CONFIG_TRACER_MAX_TRACE |
d716ff71 SRRH |
5614 | if (iter->snapshot && iter->tr->current_trace->use_max_tr) |
5615 | return -EBUSY; | |
6de58e62 SRRH |
5616 | #endif |
5617 | ||
ddd538f3 | 5618 | if (!info->spare) |
12883efb SRRH |
5619 | info->spare = ring_buffer_alloc_read_page(iter->trace_buffer->buffer, |
5620 | iter->cpu_file); | |
ddd538f3 | 5621 | if (!info->spare) |
d716ff71 | 5622 | return -ENOMEM; |
ddd538f3 | 5623 | |
2cadf913 SR |
5624 | /* Do we have previous read data to read? */ |
5625 | if (info->read < PAGE_SIZE) | |
5626 | goto read; | |
5627 | ||
b627344f | 5628 | again: |
cc60cdc9 | 5629 | trace_access_lock(iter->cpu_file); |
12883efb | 5630 | ret = ring_buffer_read_page(iter->trace_buffer->buffer, |
2cadf913 SR |
5631 | &info->spare, |
5632 | count, | |
cc60cdc9 SR |
5633 | iter->cpu_file, 0); |
5634 | trace_access_unlock(iter->cpu_file); | |
2cadf913 | 5635 | |
b627344f SR |
5636 | if (ret < 0) { |
5637 | if (trace_empty(iter)) { | |
d716ff71 SRRH |
5638 | if ((filp->f_flags & O_NONBLOCK)) |
5639 | return -EAGAIN; | |
5640 | ||
e30f53aa | 5641 | ret = wait_on_pipe(iter, false); |
d716ff71 SRRH |
5642 | if (ret) |
5643 | return ret; | |
5644 | ||
b627344f SR |
5645 | goto again; |
5646 | } | |
d716ff71 | 5647 | return 0; |
b627344f | 5648 | } |
436fc280 | 5649 | |
436fc280 | 5650 | info->read = 0; |
b627344f | 5651 | read: |
2cadf913 SR |
5652 | size = PAGE_SIZE - info->read; |
5653 | if (size > count) | |
5654 | size = count; | |
5655 | ||
5656 | ret = copy_to_user(ubuf, info->spare + info->read, size); | |
d716ff71 SRRH |
5657 | if (ret == size) |
5658 | return -EFAULT; | |
5659 | ||
2dc5d12b SR |
5660 | size -= ret; |
5661 | ||
2cadf913 SR |
5662 | *ppos += size; |
5663 | info->read += size; | |
5664 | ||
5665 | return size; | |
5666 | } | |
5667 | ||
5668 | static int tracing_buffers_release(struct inode *inode, struct file *file) | |
5669 | { | |
5670 | struct ftrace_buffer_info *info = file->private_data; | |
cc60cdc9 | 5671 | struct trace_iterator *iter = &info->iter; |
2cadf913 | 5672 | |
a695cb58 SRRH |
5673 | mutex_lock(&trace_types_lock); |
5674 | ||
cf6ab6d9 SRRH |
5675 | iter->tr->current_trace->ref--; |
5676 | ||
ff451961 | 5677 | __trace_array_put(iter->tr); |
2cadf913 | 5678 | |
ddd538f3 | 5679 | if (info->spare) |
12883efb | 5680 | ring_buffer_free_read_page(iter->trace_buffer->buffer, info->spare); |
2cadf913 SR |
5681 | kfree(info); |
5682 | ||
a695cb58 SRRH |
5683 | mutex_unlock(&trace_types_lock); |
5684 | ||
2cadf913 SR |
5685 | return 0; |
5686 | } | |
5687 | ||
5688 | struct buffer_ref { | |
5689 | struct ring_buffer *buffer; | |
5690 | void *page; | |
5691 | int ref; | |
5692 | }; | |
5693 | ||
5694 | static void buffer_pipe_buf_release(struct pipe_inode_info *pipe, | |
5695 | struct pipe_buffer *buf) | |
5696 | { | |
5697 | struct buffer_ref *ref = (struct buffer_ref *)buf->private; | |
5698 | ||
5699 | if (--ref->ref) | |
5700 | return; | |
5701 | ||
5702 | ring_buffer_free_read_page(ref->buffer, ref->page); | |
5703 | kfree(ref); | |
5704 | buf->private = 0; | |
5705 | } | |
5706 | ||
2cadf913 SR |
5707 | static void buffer_pipe_buf_get(struct pipe_inode_info *pipe, |
5708 | struct pipe_buffer *buf) | |
5709 | { | |
5710 | struct buffer_ref *ref = (struct buffer_ref *)buf->private; | |
5711 | ||
5712 | ref->ref++; | |
5713 | } | |
5714 | ||
5715 | /* Pipe buffer operations for a buffer. */ | |
28dfef8f | 5716 | static const struct pipe_buf_operations buffer_pipe_buf_ops = { |
2cadf913 | 5717 | .can_merge = 0, |
2cadf913 SR |
5718 | .confirm = generic_pipe_buf_confirm, |
5719 | .release = buffer_pipe_buf_release, | |
d55cb6cf | 5720 | .steal = generic_pipe_buf_steal, |
2cadf913 SR |
5721 | .get = buffer_pipe_buf_get, |
5722 | }; | |
5723 | ||
5724 | /* | |
5725 | * Callback from splice_to_pipe(), if we need to release some pages | |
5726 | * at the end of the spd in case we error'ed out in filling the pipe. | |
5727 | */ | |
5728 | static void buffer_spd_release(struct splice_pipe_desc *spd, unsigned int i) | |
5729 | { | |
5730 | struct buffer_ref *ref = | |
5731 | (struct buffer_ref *)spd->partial[i].private; | |
5732 | ||
5733 | if (--ref->ref) | |
5734 | return; | |
5735 | ||
5736 | ring_buffer_free_read_page(ref->buffer, ref->page); | |
5737 | kfree(ref); | |
5738 | spd->partial[i].private = 0; | |
5739 | } | |
5740 | ||
5741 | static ssize_t | |
5742 | tracing_buffers_splice_read(struct file *file, loff_t *ppos, | |
5743 | struct pipe_inode_info *pipe, size_t len, | |
5744 | unsigned int flags) | |
5745 | { | |
5746 | struct ftrace_buffer_info *info = file->private_data; | |
cc60cdc9 | 5747 | struct trace_iterator *iter = &info->iter; |
35f3d14d JA |
5748 | struct partial_page partial_def[PIPE_DEF_BUFFERS]; |
5749 | struct page *pages_def[PIPE_DEF_BUFFERS]; | |
2cadf913 | 5750 | struct splice_pipe_desc spd = { |
35f3d14d JA |
5751 | .pages = pages_def, |
5752 | .partial = partial_def, | |
047fe360 | 5753 | .nr_pages_max = PIPE_DEF_BUFFERS, |
2cadf913 SR |
5754 | .flags = flags, |
5755 | .ops = &buffer_pipe_buf_ops, | |
5756 | .spd_release = buffer_spd_release, | |
5757 | }; | |
5758 | struct buffer_ref *ref; | |
93459c6c | 5759 | int entries, size, i; |
07906da7 | 5760 | ssize_t ret = 0; |
2cadf913 | 5761 | |
6de58e62 | 5762 | #ifdef CONFIG_TRACER_MAX_TRACE |
d716ff71 SRRH |
5763 | if (iter->snapshot && iter->tr->current_trace->use_max_tr) |
5764 | return -EBUSY; | |
6de58e62 SRRH |
5765 | #endif |
5766 | ||
d716ff71 SRRH |
5767 | if (splice_grow_spd(pipe, &spd)) |
5768 | return -ENOMEM; | |
35f3d14d | 5769 | |
d716ff71 SRRH |
5770 | if (*ppos & (PAGE_SIZE - 1)) |
5771 | return -EINVAL; | |
93cfb3c9 LJ |
5772 | |
5773 | if (len & (PAGE_SIZE - 1)) { | |
d716ff71 SRRH |
5774 | if (len < PAGE_SIZE) |
5775 | return -EINVAL; | |
93cfb3c9 LJ |
5776 | len &= PAGE_MASK; |
5777 | } | |
5778 | ||
cc60cdc9 SR |
5779 | again: |
5780 | trace_access_lock(iter->cpu_file); | |
12883efb | 5781 | entries = ring_buffer_entries_cpu(iter->trace_buffer->buffer, iter->cpu_file); |
93459c6c | 5782 | |
a786c06d | 5783 | for (i = 0; i < spd.nr_pages_max && len && entries; i++, len -= PAGE_SIZE) { |
2cadf913 SR |
5784 | struct page *page; |
5785 | int r; | |
5786 | ||
5787 | ref = kzalloc(sizeof(*ref), GFP_KERNEL); | |
07906da7 RV |
5788 | if (!ref) { |
5789 | ret = -ENOMEM; | |
2cadf913 | 5790 | break; |
07906da7 | 5791 | } |
2cadf913 | 5792 | |
7267fa68 | 5793 | ref->ref = 1; |
12883efb | 5794 | ref->buffer = iter->trace_buffer->buffer; |
cc60cdc9 | 5795 | ref->page = ring_buffer_alloc_read_page(ref->buffer, iter->cpu_file); |
2cadf913 | 5796 | if (!ref->page) { |
07906da7 | 5797 | ret = -ENOMEM; |
2cadf913 SR |
5798 | kfree(ref); |
5799 | break; | |
5800 | } | |
5801 | ||
5802 | r = ring_buffer_read_page(ref->buffer, &ref->page, | |
cc60cdc9 | 5803 | len, iter->cpu_file, 1); |
2cadf913 | 5804 | if (r < 0) { |
7ea59064 | 5805 | ring_buffer_free_read_page(ref->buffer, ref->page); |
2cadf913 SR |
5806 | kfree(ref); |
5807 | break; | |
5808 | } | |
5809 | ||
5810 | /* | |
5811 | * zero out any left over data, this is going to | |
5812 | * user land. | |
5813 | */ | |
5814 | size = ring_buffer_page_len(ref->page); | |
5815 | if (size < PAGE_SIZE) | |
5816 | memset(ref->page + size, 0, PAGE_SIZE - size); | |
5817 | ||
5818 | page = virt_to_page(ref->page); | |
5819 | ||
5820 | spd.pages[i] = page; | |
5821 | spd.partial[i].len = PAGE_SIZE; | |
5822 | spd.partial[i].offset = 0; | |
5823 | spd.partial[i].private = (unsigned long)ref; | |
5824 | spd.nr_pages++; | |
93cfb3c9 | 5825 | *ppos += PAGE_SIZE; |
93459c6c | 5826 | |
12883efb | 5827 | entries = ring_buffer_entries_cpu(iter->trace_buffer->buffer, iter->cpu_file); |
2cadf913 SR |
5828 | } |
5829 | ||
cc60cdc9 | 5830 | trace_access_unlock(iter->cpu_file); |
2cadf913 SR |
5831 | spd.nr_pages = i; |
5832 | ||
5833 | /* did we read anything? */ | |
5834 | if (!spd.nr_pages) { | |
07906da7 | 5835 | if (ret) |
d716ff71 SRRH |
5836 | return ret; |
5837 | ||
5838 | if ((file->f_flags & O_NONBLOCK) || (flags & SPLICE_F_NONBLOCK)) | |
5839 | return -EAGAIN; | |
07906da7 | 5840 | |
e30f53aa | 5841 | ret = wait_on_pipe(iter, true); |
8b8b3683 | 5842 | if (ret) |
d716ff71 | 5843 | return ret; |
e30f53aa | 5844 | |
cc60cdc9 | 5845 | goto again; |
2cadf913 SR |
5846 | } |
5847 | ||
5848 | ret = splice_to_pipe(pipe, &spd); | |
047fe360 | 5849 | splice_shrink_spd(&spd); |
6de58e62 | 5850 | |
2cadf913 SR |
5851 | return ret; |
5852 | } | |
5853 | ||
5854 | static const struct file_operations tracing_buffers_fops = { | |
5855 | .open = tracing_buffers_open, | |
5856 | .read = tracing_buffers_read, | |
cc60cdc9 | 5857 | .poll = tracing_buffers_poll, |
2cadf913 SR |
5858 | .release = tracing_buffers_release, |
5859 | .splice_read = tracing_buffers_splice_read, | |
5860 | .llseek = no_llseek, | |
5861 | }; | |
5862 | ||
c8d77183 SR |
5863 | static ssize_t |
5864 | tracing_stats_read(struct file *filp, char __user *ubuf, | |
5865 | size_t count, loff_t *ppos) | |
5866 | { | |
4d3435b8 ON |
5867 | struct inode *inode = file_inode(filp); |
5868 | struct trace_array *tr = inode->i_private; | |
12883efb | 5869 | struct trace_buffer *trace_buf = &tr->trace_buffer; |
4d3435b8 | 5870 | int cpu = tracing_get_cpu(inode); |
c8d77183 SR |
5871 | struct trace_seq *s; |
5872 | unsigned long cnt; | |
c64e148a VN |
5873 | unsigned long long t; |
5874 | unsigned long usec_rem; | |
c8d77183 | 5875 | |
e4f2d10f | 5876 | s = kmalloc(sizeof(*s), GFP_KERNEL); |
c8d77183 | 5877 | if (!s) |
a646365c | 5878 | return -ENOMEM; |
c8d77183 SR |
5879 | |
5880 | trace_seq_init(s); | |
5881 | ||
12883efb | 5882 | cnt = ring_buffer_entries_cpu(trace_buf->buffer, cpu); |
c8d77183 SR |
5883 | trace_seq_printf(s, "entries: %ld\n", cnt); |
5884 | ||
12883efb | 5885 | cnt = ring_buffer_overrun_cpu(trace_buf->buffer, cpu); |
c8d77183 SR |
5886 | trace_seq_printf(s, "overrun: %ld\n", cnt); |
5887 | ||
12883efb | 5888 | cnt = ring_buffer_commit_overrun_cpu(trace_buf->buffer, cpu); |
c8d77183 SR |
5889 | trace_seq_printf(s, "commit overrun: %ld\n", cnt); |
5890 | ||
12883efb | 5891 | cnt = ring_buffer_bytes_cpu(trace_buf->buffer, cpu); |
c64e148a VN |
5892 | trace_seq_printf(s, "bytes: %ld\n", cnt); |
5893 | ||
58e8eedf | 5894 | if (trace_clocks[tr->clock_id].in_ns) { |
11043d8b | 5895 | /* local or global for trace_clock */ |
12883efb | 5896 | t = ns2usecs(ring_buffer_oldest_event_ts(trace_buf->buffer, cpu)); |
11043d8b YY |
5897 | usec_rem = do_div(t, USEC_PER_SEC); |
5898 | trace_seq_printf(s, "oldest event ts: %5llu.%06lu\n", | |
5899 | t, usec_rem); | |
5900 | ||
12883efb | 5901 | t = ns2usecs(ring_buffer_time_stamp(trace_buf->buffer, cpu)); |
11043d8b YY |
5902 | usec_rem = do_div(t, USEC_PER_SEC); |
5903 | trace_seq_printf(s, "now ts: %5llu.%06lu\n", t, usec_rem); | |
5904 | } else { | |
5905 | /* counter or tsc mode for trace_clock */ | |
5906 | trace_seq_printf(s, "oldest event ts: %llu\n", | |
12883efb | 5907 | ring_buffer_oldest_event_ts(trace_buf->buffer, cpu)); |
c64e148a | 5908 | |
11043d8b | 5909 | trace_seq_printf(s, "now ts: %llu\n", |
12883efb | 5910 | ring_buffer_time_stamp(trace_buf->buffer, cpu)); |
11043d8b | 5911 | } |
c64e148a | 5912 | |
12883efb | 5913 | cnt = ring_buffer_dropped_events_cpu(trace_buf->buffer, cpu); |
884bfe89 SP |
5914 | trace_seq_printf(s, "dropped events: %ld\n", cnt); |
5915 | ||
12883efb | 5916 | cnt = ring_buffer_read_events_cpu(trace_buf->buffer, cpu); |
ad964704 SRRH |
5917 | trace_seq_printf(s, "read events: %ld\n", cnt); |
5918 | ||
5ac48378 SRRH |
5919 | count = simple_read_from_buffer(ubuf, count, ppos, |
5920 | s->buffer, trace_seq_used(s)); | |
c8d77183 SR |
5921 | |
5922 | kfree(s); | |
5923 | ||
5924 | return count; | |
5925 | } | |
5926 | ||
5927 | static const struct file_operations tracing_stats_fops = { | |
4d3435b8 | 5928 | .open = tracing_open_generic_tr, |
c8d77183 | 5929 | .read = tracing_stats_read, |
b444786f | 5930 | .llseek = generic_file_llseek, |
4d3435b8 | 5931 | .release = tracing_release_generic_tr, |
c8d77183 SR |
5932 | }; |
5933 | ||
bc0c38d1 SR |
5934 | #ifdef CONFIG_DYNAMIC_FTRACE |
5935 | ||
b807c3d0 SR |
5936 | int __weak ftrace_arch_read_dyn_info(char *buf, int size) |
5937 | { | |
5938 | return 0; | |
5939 | } | |
5940 | ||
bc0c38d1 | 5941 | static ssize_t |
b807c3d0 | 5942 | tracing_read_dyn_info(struct file *filp, char __user *ubuf, |
bc0c38d1 SR |
5943 | size_t cnt, loff_t *ppos) |
5944 | { | |
a26a2a27 SR |
5945 | static char ftrace_dyn_info_buffer[1024]; |
5946 | static DEFINE_MUTEX(dyn_info_mutex); | |
bc0c38d1 | 5947 | unsigned long *p = filp->private_data; |
b807c3d0 | 5948 | char *buf = ftrace_dyn_info_buffer; |
a26a2a27 | 5949 | int size = ARRAY_SIZE(ftrace_dyn_info_buffer); |
bc0c38d1 SR |
5950 | int r; |
5951 | ||
b807c3d0 SR |
5952 | mutex_lock(&dyn_info_mutex); |
5953 | r = sprintf(buf, "%ld ", *p); | |
4bf39a94 | 5954 | |
a26a2a27 | 5955 | r += ftrace_arch_read_dyn_info(buf+r, (size-1)-r); |
b807c3d0 SR |
5956 | buf[r++] = '\n'; |
5957 | ||
5958 | r = simple_read_from_buffer(ubuf, cnt, ppos, buf, r); | |
5959 | ||
5960 | mutex_unlock(&dyn_info_mutex); | |
5961 | ||
5962 | return r; | |
bc0c38d1 SR |
5963 | } |
5964 | ||
5e2336a0 | 5965 | static const struct file_operations tracing_dyn_info_fops = { |
4bf39a94 | 5966 | .open = tracing_open_generic, |
b807c3d0 | 5967 | .read = tracing_read_dyn_info, |
b444786f | 5968 | .llseek = generic_file_llseek, |
bc0c38d1 | 5969 | }; |
77fd5c15 | 5970 | #endif /* CONFIG_DYNAMIC_FTRACE */ |
bc0c38d1 | 5971 | |
77fd5c15 SRRH |
5972 | #if defined(CONFIG_TRACER_SNAPSHOT) && defined(CONFIG_DYNAMIC_FTRACE) |
5973 | static void | |
5974 | ftrace_snapshot(unsigned long ip, unsigned long parent_ip, void **data) | |
5975 | { | |
5976 | tracing_snapshot(); | |
5977 | } | |
bc0c38d1 | 5978 | |
77fd5c15 SRRH |
5979 | static void |
5980 | ftrace_count_snapshot(unsigned long ip, unsigned long parent_ip, void **data) | |
bc0c38d1 | 5981 | { |
77fd5c15 SRRH |
5982 | unsigned long *count = (long *)data; |
5983 | ||
5984 | if (!*count) | |
5985 | return; | |
bc0c38d1 | 5986 | |
77fd5c15 SRRH |
5987 | if (*count != -1) |
5988 | (*count)--; | |
5989 | ||
5990 | tracing_snapshot(); | |
5991 | } | |
5992 | ||
5993 | static int | |
5994 | ftrace_snapshot_print(struct seq_file *m, unsigned long ip, | |
5995 | struct ftrace_probe_ops *ops, void *data) | |
5996 | { | |
5997 | long count = (long)data; | |
5998 | ||
5999 | seq_printf(m, "%ps:", (void *)ip); | |
6000 | ||
fa6f0cc7 | 6001 | seq_puts(m, "snapshot"); |
77fd5c15 SRRH |
6002 | |
6003 | if (count == -1) | |
fa6f0cc7 | 6004 | seq_puts(m, ":unlimited\n"); |
77fd5c15 SRRH |
6005 | else |
6006 | seq_printf(m, ":count=%ld\n", count); | |
6007 | ||
6008 | return 0; | |
6009 | } | |
6010 | ||
6011 | static struct ftrace_probe_ops snapshot_probe_ops = { | |
6012 | .func = ftrace_snapshot, | |
6013 | .print = ftrace_snapshot_print, | |
6014 | }; | |
6015 | ||
6016 | static struct ftrace_probe_ops snapshot_count_probe_ops = { | |
6017 | .func = ftrace_count_snapshot, | |
6018 | .print = ftrace_snapshot_print, | |
6019 | }; | |
6020 | ||
6021 | static int | |
6022 | ftrace_trace_snapshot_callback(struct ftrace_hash *hash, | |
6023 | char *glob, char *cmd, char *param, int enable) | |
6024 | { | |
6025 | struct ftrace_probe_ops *ops; | |
6026 | void *count = (void *)-1; | |
6027 | char *number; | |
6028 | int ret; | |
6029 | ||
6030 | /* hash funcs only work with set_ftrace_filter */ | |
6031 | if (!enable) | |
6032 | return -EINVAL; | |
6033 | ||
6034 | ops = param ? &snapshot_count_probe_ops : &snapshot_probe_ops; | |
6035 | ||
6036 | if (glob[0] == '!') { | |
6037 | unregister_ftrace_function_probe_func(glob+1, ops); | |
6038 | return 0; | |
6039 | } | |
6040 | ||
6041 | if (!param) | |
6042 | goto out_reg; | |
6043 | ||
6044 | number = strsep(¶m, ":"); | |
6045 | ||
6046 | if (!strlen(number)) | |
6047 | goto out_reg; | |
6048 | ||
6049 | /* | |
6050 | * We use the callback data field (which is a pointer) | |
6051 | * as our counter. | |
6052 | */ | |
6053 | ret = kstrtoul(number, 0, (unsigned long *)&count); | |
6054 | if (ret) | |
6055 | return ret; | |
6056 | ||
6057 | out_reg: | |
6058 | ret = register_ftrace_function_probe(glob, ops, count); | |
6059 | ||
6060 | if (ret >= 0) | |
6061 | alloc_snapshot(&global_trace); | |
6062 | ||
6063 | return ret < 0 ? ret : 0; | |
6064 | } | |
6065 | ||
6066 | static struct ftrace_func_command ftrace_snapshot_cmd = { | |
6067 | .name = "snapshot", | |
6068 | .func = ftrace_trace_snapshot_callback, | |
6069 | }; | |
6070 | ||
38de93ab | 6071 | static __init int register_snapshot_cmd(void) |
77fd5c15 SRRH |
6072 | { |
6073 | return register_ftrace_command(&ftrace_snapshot_cmd); | |
6074 | } | |
6075 | #else | |
38de93ab | 6076 | static inline __init int register_snapshot_cmd(void) { return 0; } |
77fd5c15 | 6077 | #endif /* defined(CONFIG_TRACER_SNAPSHOT) && defined(CONFIG_DYNAMIC_FTRACE) */ |
bc0c38d1 | 6078 | |
7eeafbca | 6079 | static struct dentry *tracing_get_dentry(struct trace_array *tr) |
bc0c38d1 | 6080 | { |
8434dc93 SRRH |
6081 | if (WARN_ON(!tr->dir)) |
6082 | return ERR_PTR(-ENODEV); | |
6083 | ||
6084 | /* Top directory uses NULL as the parent */ | |
6085 | if (tr->flags & TRACE_ARRAY_FL_GLOBAL) | |
6086 | return NULL; | |
6087 | ||
6088 | /* All sub buffers have a descriptor */ | |
2b6080f2 | 6089 | return tr->dir; |
bc0c38d1 SR |
6090 | } |
6091 | ||
2b6080f2 | 6092 | static struct dentry *tracing_dentry_percpu(struct trace_array *tr, int cpu) |
b04cc6b1 | 6093 | { |
b04cc6b1 FW |
6094 | struct dentry *d_tracer; |
6095 | ||
2b6080f2 SR |
6096 | if (tr->percpu_dir) |
6097 | return tr->percpu_dir; | |
b04cc6b1 | 6098 | |
7eeafbca | 6099 | d_tracer = tracing_get_dentry(tr); |
14a5ae40 | 6100 | if (IS_ERR(d_tracer)) |
b04cc6b1 FW |
6101 | return NULL; |
6102 | ||
8434dc93 | 6103 | tr->percpu_dir = tracefs_create_dir("per_cpu", d_tracer); |
b04cc6b1 | 6104 | |
2b6080f2 | 6105 | WARN_ONCE(!tr->percpu_dir, |
8434dc93 | 6106 | "Could not create tracefs directory 'per_cpu/%d'\n", cpu); |
b04cc6b1 | 6107 | |
2b6080f2 | 6108 | return tr->percpu_dir; |
b04cc6b1 FW |
6109 | } |
6110 | ||
649e9c70 ON |
6111 | static struct dentry * |
6112 | trace_create_cpu_file(const char *name, umode_t mode, struct dentry *parent, | |
6113 | void *data, long cpu, const struct file_operations *fops) | |
6114 | { | |
6115 | struct dentry *ret = trace_create_file(name, mode, parent, data, fops); | |
6116 | ||
6117 | if (ret) /* See tracing_get_cpu() */ | |
7682c918 | 6118 | d_inode(ret)->i_cdev = (void *)(cpu + 1); |
649e9c70 ON |
6119 | return ret; |
6120 | } | |
6121 | ||
2b6080f2 | 6122 | static void |
8434dc93 | 6123 | tracing_init_tracefs_percpu(struct trace_array *tr, long cpu) |
b04cc6b1 | 6124 | { |
2b6080f2 | 6125 | struct dentry *d_percpu = tracing_dentry_percpu(tr, cpu); |
5452af66 | 6126 | struct dentry *d_cpu; |
dd49a38c | 6127 | char cpu_dir[30]; /* 30 characters should be more than enough */ |
b04cc6b1 | 6128 | |
0a3d7ce7 NK |
6129 | if (!d_percpu) |
6130 | return; | |
6131 | ||
dd49a38c | 6132 | snprintf(cpu_dir, 30, "cpu%ld", cpu); |
8434dc93 | 6133 | d_cpu = tracefs_create_dir(cpu_dir, d_percpu); |
8656e7a2 | 6134 | if (!d_cpu) { |
8434dc93 | 6135 | pr_warning("Could not create tracefs '%s' entry\n", cpu_dir); |
8656e7a2 FW |
6136 | return; |
6137 | } | |
b04cc6b1 | 6138 | |
8656e7a2 | 6139 | /* per cpu trace_pipe */ |
649e9c70 | 6140 | trace_create_cpu_file("trace_pipe", 0444, d_cpu, |
15544209 | 6141 | tr, cpu, &tracing_pipe_fops); |
b04cc6b1 FW |
6142 | |
6143 | /* per cpu trace */ | |
649e9c70 | 6144 | trace_create_cpu_file("trace", 0644, d_cpu, |
6484c71c | 6145 | tr, cpu, &tracing_fops); |
7f96f93f | 6146 | |
649e9c70 | 6147 | trace_create_cpu_file("trace_pipe_raw", 0444, d_cpu, |
46ef2be0 | 6148 | tr, cpu, &tracing_buffers_fops); |
7f96f93f | 6149 | |
649e9c70 | 6150 | trace_create_cpu_file("stats", 0444, d_cpu, |
4d3435b8 | 6151 | tr, cpu, &tracing_stats_fops); |
438ced17 | 6152 | |
649e9c70 | 6153 | trace_create_cpu_file("buffer_size_kb", 0444, d_cpu, |
0bc392ee | 6154 | tr, cpu, &tracing_entries_fops); |
f1affcaa SRRH |
6155 | |
6156 | #ifdef CONFIG_TRACER_SNAPSHOT | |
649e9c70 | 6157 | trace_create_cpu_file("snapshot", 0644, d_cpu, |
6484c71c | 6158 | tr, cpu, &snapshot_fops); |
6de58e62 | 6159 | |
649e9c70 | 6160 | trace_create_cpu_file("snapshot_raw", 0444, d_cpu, |
46ef2be0 | 6161 | tr, cpu, &snapshot_raw_fops); |
f1affcaa | 6162 | #endif |
b04cc6b1 FW |
6163 | } |
6164 | ||
60a11774 SR |
6165 | #ifdef CONFIG_FTRACE_SELFTEST |
6166 | /* Let selftest have access to static functions in this file */ | |
6167 | #include "trace_selftest.c" | |
6168 | #endif | |
6169 | ||
577b785f SR |
6170 | static ssize_t |
6171 | trace_options_read(struct file *filp, char __user *ubuf, size_t cnt, | |
6172 | loff_t *ppos) | |
6173 | { | |
6174 | struct trace_option_dentry *topt = filp->private_data; | |
6175 | char *buf; | |
6176 | ||
6177 | if (topt->flags->val & topt->opt->bit) | |
6178 | buf = "1\n"; | |
6179 | else | |
6180 | buf = "0\n"; | |
6181 | ||
6182 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, 2); | |
6183 | } | |
6184 | ||
6185 | static ssize_t | |
6186 | trace_options_write(struct file *filp, const char __user *ubuf, size_t cnt, | |
6187 | loff_t *ppos) | |
6188 | { | |
6189 | struct trace_option_dentry *topt = filp->private_data; | |
6190 | unsigned long val; | |
577b785f SR |
6191 | int ret; |
6192 | ||
22fe9b54 PH |
6193 | ret = kstrtoul_from_user(ubuf, cnt, 10, &val); |
6194 | if (ret) | |
577b785f SR |
6195 | return ret; |
6196 | ||
8d18eaaf LZ |
6197 | if (val != 0 && val != 1) |
6198 | return -EINVAL; | |
577b785f | 6199 | |
8d18eaaf | 6200 | if (!!(topt->flags->val & topt->opt->bit) != val) { |
577b785f | 6201 | mutex_lock(&trace_types_lock); |
8c1a49ae | 6202 | ret = __set_tracer_option(topt->tr, topt->flags, |
c757bea9 | 6203 | topt->opt, !val); |
577b785f SR |
6204 | mutex_unlock(&trace_types_lock); |
6205 | if (ret) | |
6206 | return ret; | |
577b785f SR |
6207 | } |
6208 | ||
6209 | *ppos += cnt; | |
6210 | ||
6211 | return cnt; | |
6212 | } | |
6213 | ||
6214 | ||
6215 | static const struct file_operations trace_options_fops = { | |
6216 | .open = tracing_open_generic, | |
6217 | .read = trace_options_read, | |
6218 | .write = trace_options_write, | |
b444786f | 6219 | .llseek = generic_file_llseek, |
577b785f SR |
6220 | }; |
6221 | ||
9a38a885 SRRH |
6222 | /* |
6223 | * In order to pass in both the trace_array descriptor as well as the index | |
6224 | * to the flag that the trace option file represents, the trace_array | |
6225 | * has a character array of trace_flags_index[], which holds the index | |
6226 | * of the bit for the flag it represents. index[0] == 0, index[1] == 1, etc. | |
6227 | * The address of this character array is passed to the flag option file | |
6228 | * read/write callbacks. | |
6229 | * | |
6230 | * In order to extract both the index and the trace_array descriptor, | |
6231 | * get_tr_index() uses the following algorithm. | |
6232 | * | |
6233 | * idx = *ptr; | |
6234 | * | |
6235 | * As the pointer itself contains the address of the index (remember | |
6236 | * index[1] == 1). | |
6237 | * | |
6238 | * Then to get the trace_array descriptor, by subtracting that index | |
6239 | * from the ptr, we get to the start of the index itself. | |
6240 | * | |
6241 | * ptr - idx == &index[0] | |
6242 | * | |
6243 | * Then a simple container_of() from that pointer gets us to the | |
6244 | * trace_array descriptor. | |
6245 | */ | |
6246 | static void get_tr_index(void *data, struct trace_array **ptr, | |
6247 | unsigned int *pindex) | |
6248 | { | |
6249 | *pindex = *(unsigned char *)data; | |
6250 | ||
6251 | *ptr = container_of(data - *pindex, struct trace_array, | |
6252 | trace_flags_index); | |
6253 | } | |
6254 | ||
a8259075 SR |
6255 | static ssize_t |
6256 | trace_options_core_read(struct file *filp, char __user *ubuf, size_t cnt, | |
6257 | loff_t *ppos) | |
6258 | { | |
9a38a885 SRRH |
6259 | void *tr_index = filp->private_data; |
6260 | struct trace_array *tr; | |
6261 | unsigned int index; | |
a8259075 SR |
6262 | char *buf; |
6263 | ||
9a38a885 SRRH |
6264 | get_tr_index(tr_index, &tr, &index); |
6265 | ||
6266 | if (tr->trace_flags & (1 << index)) | |
a8259075 SR |
6267 | buf = "1\n"; |
6268 | else | |
6269 | buf = "0\n"; | |
6270 | ||
6271 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, 2); | |
6272 | } | |
6273 | ||
6274 | static ssize_t | |
6275 | trace_options_core_write(struct file *filp, const char __user *ubuf, size_t cnt, | |
6276 | loff_t *ppos) | |
6277 | { | |
9a38a885 SRRH |
6278 | void *tr_index = filp->private_data; |
6279 | struct trace_array *tr; | |
6280 | unsigned int index; | |
a8259075 SR |
6281 | unsigned long val; |
6282 | int ret; | |
6283 | ||
9a38a885 SRRH |
6284 | get_tr_index(tr_index, &tr, &index); |
6285 | ||
22fe9b54 PH |
6286 | ret = kstrtoul_from_user(ubuf, cnt, 10, &val); |
6287 | if (ret) | |
a8259075 SR |
6288 | return ret; |
6289 | ||
f2d84b65 | 6290 | if (val != 0 && val != 1) |
a8259075 | 6291 | return -EINVAL; |
69d34da2 SRRH |
6292 | |
6293 | mutex_lock(&trace_types_lock); | |
2b6080f2 | 6294 | ret = set_tracer_flag(tr, 1 << index, val); |
69d34da2 | 6295 | mutex_unlock(&trace_types_lock); |
a8259075 | 6296 | |
613f04a0 SRRH |
6297 | if (ret < 0) |
6298 | return ret; | |
6299 | ||
a8259075 SR |
6300 | *ppos += cnt; |
6301 | ||
6302 | return cnt; | |
6303 | } | |
6304 | ||
a8259075 SR |
6305 | static const struct file_operations trace_options_core_fops = { |
6306 | .open = tracing_open_generic, | |
6307 | .read = trace_options_core_read, | |
6308 | .write = trace_options_core_write, | |
b444786f | 6309 | .llseek = generic_file_llseek, |
a8259075 SR |
6310 | }; |
6311 | ||
5452af66 | 6312 | struct dentry *trace_create_file(const char *name, |
f4ae40a6 | 6313 | umode_t mode, |
5452af66 FW |
6314 | struct dentry *parent, |
6315 | void *data, | |
6316 | const struct file_operations *fops) | |
6317 | { | |
6318 | struct dentry *ret; | |
6319 | ||
8434dc93 | 6320 | ret = tracefs_create_file(name, mode, parent, data, fops); |
5452af66 | 6321 | if (!ret) |
8434dc93 | 6322 | pr_warning("Could not create tracefs '%s' entry\n", name); |
5452af66 FW |
6323 | |
6324 | return ret; | |
6325 | } | |
6326 | ||
6327 | ||
2b6080f2 | 6328 | static struct dentry *trace_options_init_dentry(struct trace_array *tr) |
a8259075 SR |
6329 | { |
6330 | struct dentry *d_tracer; | |
a8259075 | 6331 | |
2b6080f2 SR |
6332 | if (tr->options) |
6333 | return tr->options; | |
a8259075 | 6334 | |
7eeafbca | 6335 | d_tracer = tracing_get_dentry(tr); |
14a5ae40 | 6336 | if (IS_ERR(d_tracer)) |
a8259075 SR |
6337 | return NULL; |
6338 | ||
8434dc93 | 6339 | tr->options = tracefs_create_dir("options", d_tracer); |
2b6080f2 | 6340 | if (!tr->options) { |
8434dc93 | 6341 | pr_warning("Could not create tracefs directory 'options'\n"); |
a8259075 SR |
6342 | return NULL; |
6343 | } | |
6344 | ||
2b6080f2 | 6345 | return tr->options; |
a8259075 SR |
6346 | } |
6347 | ||
577b785f | 6348 | static void |
2b6080f2 SR |
6349 | create_trace_option_file(struct trace_array *tr, |
6350 | struct trace_option_dentry *topt, | |
577b785f SR |
6351 | struct tracer_flags *flags, |
6352 | struct tracer_opt *opt) | |
6353 | { | |
6354 | struct dentry *t_options; | |
577b785f | 6355 | |
2b6080f2 | 6356 | t_options = trace_options_init_dentry(tr); |
577b785f SR |
6357 | if (!t_options) |
6358 | return; | |
6359 | ||
6360 | topt->flags = flags; | |
6361 | topt->opt = opt; | |
2b6080f2 | 6362 | topt->tr = tr; |
577b785f | 6363 | |
5452af66 | 6364 | topt->entry = trace_create_file(opt->name, 0644, t_options, topt, |
577b785f SR |
6365 | &trace_options_fops); |
6366 | ||
577b785f SR |
6367 | } |
6368 | ||
37aea98b | 6369 | static void |
2b6080f2 | 6370 | create_trace_option_files(struct trace_array *tr, struct tracer *tracer) |
577b785f SR |
6371 | { |
6372 | struct trace_option_dentry *topts; | |
37aea98b | 6373 | struct trace_options *tr_topts; |
577b785f SR |
6374 | struct tracer_flags *flags; |
6375 | struct tracer_opt *opts; | |
6376 | int cnt; | |
37aea98b | 6377 | int i; |
577b785f SR |
6378 | |
6379 | if (!tracer) | |
37aea98b | 6380 | return; |
577b785f SR |
6381 | |
6382 | flags = tracer->flags; | |
6383 | ||
6384 | if (!flags || !flags->opts) | |
37aea98b SRRH |
6385 | return; |
6386 | ||
6387 | /* | |
6388 | * If this is an instance, only create flags for tracers | |
6389 | * the instance may have. | |
6390 | */ | |
6391 | if (!trace_ok_for_array(tracer, tr)) | |
6392 | return; | |
6393 | ||
6394 | for (i = 0; i < tr->nr_topts; i++) { | |
6395 | /* | |
6396 | * Check if these flags have already been added. | |
6397 | * Some tracers share flags. | |
6398 | */ | |
6399 | if (tr->topts[i].tracer->flags == tracer->flags) | |
6400 | return; | |
6401 | } | |
577b785f SR |
6402 | |
6403 | opts = flags->opts; | |
6404 | ||
6405 | for (cnt = 0; opts[cnt].name; cnt++) | |
6406 | ; | |
6407 | ||
0cfe8245 | 6408 | topts = kcalloc(cnt + 1, sizeof(*topts), GFP_KERNEL); |
577b785f | 6409 | if (!topts) |
37aea98b SRRH |
6410 | return; |
6411 | ||
6412 | tr_topts = krealloc(tr->topts, sizeof(*tr->topts) * (tr->nr_topts + 1), | |
6413 | GFP_KERNEL); | |
6414 | if (!tr_topts) { | |
6415 | kfree(topts); | |
6416 | return; | |
6417 | } | |
6418 | ||
6419 | tr->topts = tr_topts; | |
6420 | tr->topts[tr->nr_topts].tracer = tracer; | |
6421 | tr->topts[tr->nr_topts].topts = topts; | |
6422 | tr->nr_topts++; | |
577b785f | 6423 | |
41d9c0be | 6424 | for (cnt = 0; opts[cnt].name; cnt++) { |
2b6080f2 | 6425 | create_trace_option_file(tr, &topts[cnt], flags, |
577b785f | 6426 | &opts[cnt]); |
41d9c0be SRRH |
6427 | WARN_ONCE(topts[cnt].entry == NULL, |
6428 | "Failed to create trace option: %s", | |
6429 | opts[cnt].name); | |
6430 | } | |
577b785f SR |
6431 | } |
6432 | ||
a8259075 | 6433 | static struct dentry * |
2b6080f2 SR |
6434 | create_trace_option_core_file(struct trace_array *tr, |
6435 | const char *option, long index) | |
a8259075 SR |
6436 | { |
6437 | struct dentry *t_options; | |
a8259075 | 6438 | |
2b6080f2 | 6439 | t_options = trace_options_init_dentry(tr); |
a8259075 SR |
6440 | if (!t_options) |
6441 | return NULL; | |
6442 | ||
9a38a885 SRRH |
6443 | return trace_create_file(option, 0644, t_options, |
6444 | (void *)&tr->trace_flags_index[index], | |
6445 | &trace_options_core_fops); | |
a8259075 SR |
6446 | } |
6447 | ||
16270145 | 6448 | static void create_trace_options_dir(struct trace_array *tr) |
a8259075 SR |
6449 | { |
6450 | struct dentry *t_options; | |
16270145 | 6451 | bool top_level = tr == &global_trace; |
a8259075 SR |
6452 | int i; |
6453 | ||
2b6080f2 | 6454 | t_options = trace_options_init_dentry(tr); |
a8259075 SR |
6455 | if (!t_options) |
6456 | return; | |
6457 | ||
16270145 SRRH |
6458 | for (i = 0; trace_options[i]; i++) { |
6459 | if (top_level || | |
6460 | !((1 << i) & TOP_LEVEL_TRACE_FLAGS)) | |
6461 | create_trace_option_core_file(tr, trace_options[i], i); | |
6462 | } | |
a8259075 SR |
6463 | } |
6464 | ||
499e5470 SR |
6465 | static ssize_t |
6466 | rb_simple_read(struct file *filp, char __user *ubuf, | |
6467 | size_t cnt, loff_t *ppos) | |
6468 | { | |
348f0fc2 | 6469 | struct trace_array *tr = filp->private_data; |
499e5470 SR |
6470 | char buf[64]; |
6471 | int r; | |
6472 | ||
10246fa3 | 6473 | r = tracer_tracing_is_on(tr); |
499e5470 SR |
6474 | r = sprintf(buf, "%d\n", r); |
6475 | ||
6476 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, r); | |
6477 | } | |
6478 | ||
6479 | static ssize_t | |
6480 | rb_simple_write(struct file *filp, const char __user *ubuf, | |
6481 | size_t cnt, loff_t *ppos) | |
6482 | { | |
348f0fc2 | 6483 | struct trace_array *tr = filp->private_data; |
12883efb | 6484 | struct ring_buffer *buffer = tr->trace_buffer.buffer; |
499e5470 SR |
6485 | unsigned long val; |
6486 | int ret; | |
6487 | ||
6488 | ret = kstrtoul_from_user(ubuf, cnt, 10, &val); | |
6489 | if (ret) | |
6490 | return ret; | |
6491 | ||
6492 | if (buffer) { | |
2df8f8a6 SR |
6493 | mutex_lock(&trace_types_lock); |
6494 | if (val) { | |
10246fa3 | 6495 | tracer_tracing_on(tr); |
2b6080f2 SR |
6496 | if (tr->current_trace->start) |
6497 | tr->current_trace->start(tr); | |
2df8f8a6 | 6498 | } else { |
10246fa3 | 6499 | tracer_tracing_off(tr); |
2b6080f2 SR |
6500 | if (tr->current_trace->stop) |
6501 | tr->current_trace->stop(tr); | |
2df8f8a6 SR |
6502 | } |
6503 | mutex_unlock(&trace_types_lock); | |
499e5470 SR |
6504 | } |
6505 | ||
6506 | (*ppos)++; | |
6507 | ||
6508 | return cnt; | |
6509 | } | |
6510 | ||
6511 | static const struct file_operations rb_simple_fops = { | |
7b85af63 | 6512 | .open = tracing_open_generic_tr, |
499e5470 SR |
6513 | .read = rb_simple_read, |
6514 | .write = rb_simple_write, | |
7b85af63 | 6515 | .release = tracing_release_generic_tr, |
499e5470 SR |
6516 | .llseek = default_llseek, |
6517 | }; | |
6518 | ||
277ba044 SR |
6519 | struct dentry *trace_instance_dir; |
6520 | ||
6521 | static void | |
8434dc93 | 6522 | init_tracer_tracefs(struct trace_array *tr, struct dentry *d_tracer); |
277ba044 | 6523 | |
55034cd6 SRRH |
6524 | static int |
6525 | allocate_trace_buffer(struct trace_array *tr, struct trace_buffer *buf, int size) | |
277ba044 SR |
6526 | { |
6527 | enum ring_buffer_flags rb_flags; | |
737223fb | 6528 | |
983f938a | 6529 | rb_flags = tr->trace_flags & TRACE_ITER_OVERWRITE ? RB_FL_OVERWRITE : 0; |
737223fb | 6530 | |
dced341b SRRH |
6531 | buf->tr = tr; |
6532 | ||
55034cd6 SRRH |
6533 | buf->buffer = ring_buffer_alloc(size, rb_flags); |
6534 | if (!buf->buffer) | |
6535 | return -ENOMEM; | |
737223fb | 6536 | |
55034cd6 SRRH |
6537 | buf->data = alloc_percpu(struct trace_array_cpu); |
6538 | if (!buf->data) { | |
6539 | ring_buffer_free(buf->buffer); | |
6540 | return -ENOMEM; | |
6541 | } | |
737223fb | 6542 | |
737223fb SRRH |
6543 | /* Allocate the first page for all buffers */ |
6544 | set_buffer_entries(&tr->trace_buffer, | |
6545 | ring_buffer_size(tr->trace_buffer.buffer, 0)); | |
6546 | ||
55034cd6 SRRH |
6547 | return 0; |
6548 | } | |
737223fb | 6549 | |
55034cd6 SRRH |
6550 | static int allocate_trace_buffers(struct trace_array *tr, int size) |
6551 | { | |
6552 | int ret; | |
737223fb | 6553 | |
55034cd6 SRRH |
6554 | ret = allocate_trace_buffer(tr, &tr->trace_buffer, size); |
6555 | if (ret) | |
6556 | return ret; | |
737223fb | 6557 | |
55034cd6 SRRH |
6558 | #ifdef CONFIG_TRACER_MAX_TRACE |
6559 | ret = allocate_trace_buffer(tr, &tr->max_buffer, | |
6560 | allocate_snapshot ? size : 1); | |
6561 | if (WARN_ON(ret)) { | |
737223fb | 6562 | ring_buffer_free(tr->trace_buffer.buffer); |
55034cd6 SRRH |
6563 | free_percpu(tr->trace_buffer.data); |
6564 | return -ENOMEM; | |
6565 | } | |
6566 | tr->allocated_snapshot = allocate_snapshot; | |
737223fb | 6567 | |
55034cd6 SRRH |
6568 | /* |
6569 | * Only the top level trace array gets its snapshot allocated | |
6570 | * from the kernel command line. | |
6571 | */ | |
6572 | allocate_snapshot = false; | |
737223fb | 6573 | #endif |
55034cd6 | 6574 | return 0; |
737223fb SRRH |
6575 | } |
6576 | ||
f0b70cc4 SRRH |
6577 | static void free_trace_buffer(struct trace_buffer *buf) |
6578 | { | |
6579 | if (buf->buffer) { | |
6580 | ring_buffer_free(buf->buffer); | |
6581 | buf->buffer = NULL; | |
6582 | free_percpu(buf->data); | |
6583 | buf->data = NULL; | |
6584 | } | |
6585 | } | |
6586 | ||
23aaa3c1 SRRH |
6587 | static void free_trace_buffers(struct trace_array *tr) |
6588 | { | |
6589 | if (!tr) | |
6590 | return; | |
6591 | ||
f0b70cc4 | 6592 | free_trace_buffer(&tr->trace_buffer); |
23aaa3c1 SRRH |
6593 | |
6594 | #ifdef CONFIG_TRACER_MAX_TRACE | |
f0b70cc4 | 6595 | free_trace_buffer(&tr->max_buffer); |
23aaa3c1 SRRH |
6596 | #endif |
6597 | } | |
6598 | ||
9a38a885 SRRH |
6599 | static void init_trace_flags_index(struct trace_array *tr) |
6600 | { | |
6601 | int i; | |
6602 | ||
6603 | /* Used by the trace options files */ | |
6604 | for (i = 0; i < TRACE_FLAGS_MAX_SIZE; i++) | |
6605 | tr->trace_flags_index[i] = i; | |
6606 | } | |
6607 | ||
37aea98b SRRH |
6608 | static void __update_tracer_options(struct trace_array *tr) |
6609 | { | |
6610 | struct tracer *t; | |
6611 | ||
6612 | for (t = trace_types; t; t = t->next) | |
6613 | add_tracer_options(tr, t); | |
6614 | } | |
6615 | ||
6616 | static void update_tracer_options(struct trace_array *tr) | |
6617 | { | |
6618 | mutex_lock(&trace_types_lock); | |
6619 | __update_tracer_options(tr); | |
6620 | mutex_unlock(&trace_types_lock); | |
6621 | } | |
6622 | ||
eae47358 | 6623 | static int instance_mkdir(const char *name) |
737223fb | 6624 | { |
277ba044 SR |
6625 | struct trace_array *tr; |
6626 | int ret; | |
277ba044 SR |
6627 | |
6628 | mutex_lock(&trace_types_lock); | |
6629 | ||
6630 | ret = -EEXIST; | |
6631 | list_for_each_entry(tr, &ftrace_trace_arrays, list) { | |
6632 | if (tr->name && strcmp(tr->name, name) == 0) | |
6633 | goto out_unlock; | |
6634 | } | |
6635 | ||
6636 | ret = -ENOMEM; | |
6637 | tr = kzalloc(sizeof(*tr), GFP_KERNEL); | |
6638 | if (!tr) | |
6639 | goto out_unlock; | |
6640 | ||
6641 | tr->name = kstrdup(name, GFP_KERNEL); | |
6642 | if (!tr->name) | |
6643 | goto out_free_tr; | |
6644 | ||
ccfe9e42 AL |
6645 | if (!alloc_cpumask_var(&tr->tracing_cpumask, GFP_KERNEL)) |
6646 | goto out_free_tr; | |
6647 | ||
983f938a SRRH |
6648 | tr->trace_flags = global_trace.trace_flags; |
6649 | ||
ccfe9e42 AL |
6650 | cpumask_copy(tr->tracing_cpumask, cpu_all_mask); |
6651 | ||
277ba044 SR |
6652 | raw_spin_lock_init(&tr->start_lock); |
6653 | ||
0b9b12c1 SRRH |
6654 | tr->max_lock = (arch_spinlock_t)__ARCH_SPIN_LOCK_UNLOCKED; |
6655 | ||
277ba044 SR |
6656 | tr->current_trace = &nop_trace; |
6657 | ||
6658 | INIT_LIST_HEAD(&tr->systems); | |
6659 | INIT_LIST_HEAD(&tr->events); | |
6660 | ||
737223fb | 6661 | if (allocate_trace_buffers(tr, trace_buf_size) < 0) |
277ba044 SR |
6662 | goto out_free_tr; |
6663 | ||
8434dc93 | 6664 | tr->dir = tracefs_create_dir(name, trace_instance_dir); |
277ba044 SR |
6665 | if (!tr->dir) |
6666 | goto out_free_tr; | |
6667 | ||
6668 | ret = event_trace_add_tracer(tr->dir, tr); | |
609e85a7 | 6669 | if (ret) { |
8434dc93 | 6670 | tracefs_remove_recursive(tr->dir); |
277ba044 | 6671 | goto out_free_tr; |
609e85a7 | 6672 | } |
277ba044 | 6673 | |
8434dc93 | 6674 | init_tracer_tracefs(tr, tr->dir); |
9a38a885 | 6675 | init_trace_flags_index(tr); |
37aea98b | 6676 | __update_tracer_options(tr); |
277ba044 SR |
6677 | |
6678 | list_add(&tr->list, &ftrace_trace_arrays); | |
6679 | ||
6680 | mutex_unlock(&trace_types_lock); | |
6681 | ||
6682 | return 0; | |
6683 | ||
6684 | out_free_tr: | |
23aaa3c1 | 6685 | free_trace_buffers(tr); |
ccfe9e42 | 6686 | free_cpumask_var(tr->tracing_cpumask); |
277ba044 SR |
6687 | kfree(tr->name); |
6688 | kfree(tr); | |
6689 | ||
6690 | out_unlock: | |
6691 | mutex_unlock(&trace_types_lock); | |
6692 | ||
6693 | return ret; | |
6694 | ||
6695 | } | |
6696 | ||
eae47358 | 6697 | static int instance_rmdir(const char *name) |
0c8916c3 SR |
6698 | { |
6699 | struct trace_array *tr; | |
6700 | int found = 0; | |
6701 | int ret; | |
37aea98b | 6702 | int i; |
0c8916c3 SR |
6703 | |
6704 | mutex_lock(&trace_types_lock); | |
6705 | ||
6706 | ret = -ENODEV; | |
6707 | list_for_each_entry(tr, &ftrace_trace_arrays, list) { | |
6708 | if (tr->name && strcmp(tr->name, name) == 0) { | |
6709 | found = 1; | |
6710 | break; | |
6711 | } | |
6712 | } | |
6713 | if (!found) | |
6714 | goto out_unlock; | |
6715 | ||
a695cb58 | 6716 | ret = -EBUSY; |
cf6ab6d9 | 6717 | if (tr->ref || (tr->current_trace && tr->current_trace->ref)) |
a695cb58 SRRH |
6718 | goto out_unlock; |
6719 | ||
0c8916c3 SR |
6720 | list_del(&tr->list); |
6721 | ||
6b450d25 | 6722 | tracing_set_nop(tr); |
0c8916c3 | 6723 | event_trace_del_tracer(tr); |
591dffda | 6724 | ftrace_destroy_function_files(tr); |
681a4a2f | 6725 | tracefs_remove_recursive(tr->dir); |
a9fcaaac | 6726 | free_trace_buffers(tr); |
0c8916c3 | 6727 | |
37aea98b SRRH |
6728 | for (i = 0; i < tr->nr_topts; i++) { |
6729 | kfree(tr->topts[i].topts); | |
6730 | } | |
6731 | kfree(tr->topts); | |
6732 | ||
0c8916c3 SR |
6733 | kfree(tr->name); |
6734 | kfree(tr); | |
6735 | ||
6736 | ret = 0; | |
6737 | ||
6738 | out_unlock: | |
6739 | mutex_unlock(&trace_types_lock); | |
6740 | ||
6741 | return ret; | |
6742 | } | |
6743 | ||
277ba044 SR |
6744 | static __init void create_trace_instances(struct dentry *d_tracer) |
6745 | { | |
eae47358 SRRH |
6746 | trace_instance_dir = tracefs_create_instance_dir("instances", d_tracer, |
6747 | instance_mkdir, | |
6748 | instance_rmdir); | |
277ba044 SR |
6749 | if (WARN_ON(!trace_instance_dir)) |
6750 | return; | |
277ba044 SR |
6751 | } |
6752 | ||
2b6080f2 | 6753 | static void |
8434dc93 | 6754 | init_tracer_tracefs(struct trace_array *tr, struct dentry *d_tracer) |
2b6080f2 | 6755 | { |
121aaee7 | 6756 | int cpu; |
2b6080f2 | 6757 | |
607e2ea1 SRRH |
6758 | trace_create_file("available_tracers", 0444, d_tracer, |
6759 | tr, &show_traces_fops); | |
6760 | ||
6761 | trace_create_file("current_tracer", 0644, d_tracer, | |
6762 | tr, &set_tracer_fops); | |
6763 | ||
ccfe9e42 AL |
6764 | trace_create_file("tracing_cpumask", 0644, d_tracer, |
6765 | tr, &tracing_cpumask_fops); | |
6766 | ||
2b6080f2 SR |
6767 | trace_create_file("trace_options", 0644, d_tracer, |
6768 | tr, &tracing_iter_fops); | |
6769 | ||
6770 | trace_create_file("trace", 0644, d_tracer, | |
6484c71c | 6771 | tr, &tracing_fops); |
2b6080f2 SR |
6772 | |
6773 | trace_create_file("trace_pipe", 0444, d_tracer, | |
15544209 | 6774 | tr, &tracing_pipe_fops); |
2b6080f2 SR |
6775 | |
6776 | trace_create_file("buffer_size_kb", 0644, d_tracer, | |
0bc392ee | 6777 | tr, &tracing_entries_fops); |
2b6080f2 SR |
6778 | |
6779 | trace_create_file("buffer_total_size_kb", 0444, d_tracer, | |
6780 | tr, &tracing_total_entries_fops); | |
6781 | ||
238ae93d | 6782 | trace_create_file("free_buffer", 0200, d_tracer, |
2b6080f2 SR |
6783 | tr, &tracing_free_buffer_fops); |
6784 | ||
6785 | trace_create_file("trace_marker", 0220, d_tracer, | |
6786 | tr, &tracing_mark_fops); | |
6787 | ||
6788 | trace_create_file("trace_clock", 0644, d_tracer, tr, | |
6789 | &trace_clock_fops); | |
6790 | ||
6791 | trace_create_file("tracing_on", 0644, d_tracer, | |
6484c71c | 6792 | tr, &rb_simple_fops); |
ce9bae55 | 6793 | |
16270145 SRRH |
6794 | create_trace_options_dir(tr); |
6795 | ||
6d9b3fa5 SRRH |
6796 | #ifdef CONFIG_TRACER_MAX_TRACE |
6797 | trace_create_file("tracing_max_latency", 0644, d_tracer, | |
6798 | &tr->max_latency, &tracing_max_lat_fops); | |
6799 | #endif | |
6800 | ||
591dffda SRRH |
6801 | if (ftrace_create_function_files(tr, d_tracer)) |
6802 | WARN(1, "Could not allocate function filter files"); | |
6803 | ||
ce9bae55 SRRH |
6804 | #ifdef CONFIG_TRACER_SNAPSHOT |
6805 | trace_create_file("snapshot", 0644, d_tracer, | |
6484c71c | 6806 | tr, &snapshot_fops); |
ce9bae55 | 6807 | #endif |
121aaee7 SRRH |
6808 | |
6809 | for_each_tracing_cpu(cpu) | |
8434dc93 | 6810 | tracing_init_tracefs_percpu(tr, cpu); |
121aaee7 | 6811 | |
2b6080f2 SR |
6812 | } |
6813 | ||
f76180bc SRRH |
6814 | static struct vfsmount *trace_automount(void *ingore) |
6815 | { | |
6816 | struct vfsmount *mnt; | |
6817 | struct file_system_type *type; | |
6818 | ||
6819 | /* | |
6820 | * To maintain backward compatibility for tools that mount | |
6821 | * debugfs to get to the tracing facility, tracefs is automatically | |
6822 | * mounted to the debugfs/tracing directory. | |
6823 | */ | |
6824 | type = get_fs_type("tracefs"); | |
6825 | if (!type) | |
6826 | return NULL; | |
6827 | mnt = vfs_kern_mount(type, 0, "tracefs", NULL); | |
6828 | put_filesystem(type); | |
6829 | if (IS_ERR(mnt)) | |
6830 | return NULL; | |
6831 | mntget(mnt); | |
6832 | ||
6833 | return mnt; | |
6834 | } | |
6835 | ||
7eeafbca SRRH |
6836 | /** |
6837 | * tracing_init_dentry - initialize top level trace array | |
6838 | * | |
6839 | * This is called when creating files or directories in the tracing | |
6840 | * directory. It is called via fs_initcall() by any of the boot up code | |
6841 | * and expects to return the dentry of the top level tracing directory. | |
6842 | */ | |
6843 | struct dentry *tracing_init_dentry(void) | |
6844 | { | |
6845 | struct trace_array *tr = &global_trace; | |
6846 | ||
f76180bc | 6847 | /* The top level trace array uses NULL as parent */ |
7eeafbca | 6848 | if (tr->dir) |
f76180bc | 6849 | return NULL; |
7eeafbca SRRH |
6850 | |
6851 | if (WARN_ON(!debugfs_initialized())) | |
6852 | return ERR_PTR(-ENODEV); | |
6853 | ||
f76180bc SRRH |
6854 | /* |
6855 | * As there may still be users that expect the tracing | |
6856 | * files to exist in debugfs/tracing, we must automount | |
6857 | * the tracefs file system there, so older tools still | |
6858 | * work with the newer kerenl. | |
6859 | */ | |
6860 | tr->dir = debugfs_create_automount("tracing", NULL, | |
6861 | trace_automount, NULL); | |
7eeafbca SRRH |
6862 | if (!tr->dir) { |
6863 | pr_warn_once("Could not create debugfs directory 'tracing'\n"); | |
6864 | return ERR_PTR(-ENOMEM); | |
6865 | } | |
6866 | ||
8434dc93 | 6867 | return NULL; |
7eeafbca SRRH |
6868 | } |
6869 | ||
0c564a53 SRRH |
6870 | extern struct trace_enum_map *__start_ftrace_enum_maps[]; |
6871 | extern struct trace_enum_map *__stop_ftrace_enum_maps[]; | |
6872 | ||
6873 | static void __init trace_enum_init(void) | |
6874 | { | |
3673b8e4 SRRH |
6875 | int len; |
6876 | ||
6877 | len = __stop_ftrace_enum_maps - __start_ftrace_enum_maps; | |
9828413d | 6878 | trace_insert_enum_map(NULL, __start_ftrace_enum_maps, len); |
3673b8e4 SRRH |
6879 | } |
6880 | ||
6881 | #ifdef CONFIG_MODULES | |
6882 | static void trace_module_add_enums(struct module *mod) | |
6883 | { | |
6884 | if (!mod->num_trace_enums) | |
6885 | return; | |
6886 | ||
6887 | /* | |
6888 | * Modules with bad taint do not have events created, do | |
6889 | * not bother with enums either. | |
6890 | */ | |
6891 | if (trace_module_has_bad_taint(mod)) | |
6892 | return; | |
6893 | ||
9828413d | 6894 | trace_insert_enum_map(mod, mod->trace_enums, mod->num_trace_enums); |
3673b8e4 SRRH |
6895 | } |
6896 | ||
9828413d SRRH |
6897 | #ifdef CONFIG_TRACE_ENUM_MAP_FILE |
6898 | static void trace_module_remove_enums(struct module *mod) | |
6899 | { | |
6900 | union trace_enum_map_item *map; | |
6901 | union trace_enum_map_item **last = &trace_enum_maps; | |
6902 | ||
6903 | if (!mod->num_trace_enums) | |
6904 | return; | |
6905 | ||
6906 | mutex_lock(&trace_enum_mutex); | |
6907 | ||
6908 | map = trace_enum_maps; | |
6909 | ||
6910 | while (map) { | |
6911 | if (map->head.mod == mod) | |
6912 | break; | |
6913 | map = trace_enum_jmp_to_tail(map); | |
6914 | last = &map->tail.next; | |
6915 | map = map->tail.next; | |
6916 | } | |
6917 | if (!map) | |
6918 | goto out; | |
6919 | ||
6920 | *last = trace_enum_jmp_to_tail(map)->tail.next; | |
6921 | kfree(map); | |
6922 | out: | |
6923 | mutex_unlock(&trace_enum_mutex); | |
6924 | } | |
6925 | #else | |
6926 | static inline void trace_module_remove_enums(struct module *mod) { } | |
6927 | #endif /* CONFIG_TRACE_ENUM_MAP_FILE */ | |
6928 | ||
3673b8e4 SRRH |
6929 | static int trace_module_notify(struct notifier_block *self, |
6930 | unsigned long val, void *data) | |
6931 | { | |
6932 | struct module *mod = data; | |
6933 | ||
6934 | switch (val) { | |
6935 | case MODULE_STATE_COMING: | |
6936 | trace_module_add_enums(mod); | |
6937 | break; | |
9828413d SRRH |
6938 | case MODULE_STATE_GOING: |
6939 | trace_module_remove_enums(mod); | |
6940 | break; | |
3673b8e4 SRRH |
6941 | } |
6942 | ||
6943 | return 0; | |
0c564a53 SRRH |
6944 | } |
6945 | ||
3673b8e4 SRRH |
6946 | static struct notifier_block trace_module_nb = { |
6947 | .notifier_call = trace_module_notify, | |
6948 | .priority = 0, | |
6949 | }; | |
9828413d | 6950 | #endif /* CONFIG_MODULES */ |
3673b8e4 | 6951 | |
8434dc93 | 6952 | static __init int tracer_init_tracefs(void) |
bc0c38d1 SR |
6953 | { |
6954 | struct dentry *d_tracer; | |
bc0c38d1 | 6955 | |
7e53bd42 LJ |
6956 | trace_access_lock_init(); |
6957 | ||
bc0c38d1 | 6958 | d_tracer = tracing_init_dentry(); |
14a5ae40 | 6959 | if (IS_ERR(d_tracer)) |
ed6f1c99 | 6960 | return 0; |
bc0c38d1 | 6961 | |
8434dc93 | 6962 | init_tracer_tracefs(&global_trace, d_tracer); |
bc0c38d1 | 6963 | |
5452af66 | 6964 | trace_create_file("tracing_thresh", 0644, d_tracer, |
6508fa76 | 6965 | &global_trace, &tracing_thresh_fops); |
a8259075 | 6966 | |
339ae5d3 | 6967 | trace_create_file("README", 0444, d_tracer, |
5452af66 FW |
6968 | NULL, &tracing_readme_fops); |
6969 | ||
69abe6a5 AP |
6970 | trace_create_file("saved_cmdlines", 0444, d_tracer, |
6971 | NULL, &tracing_saved_cmdlines_fops); | |
5bf9a1ee | 6972 | |
939c7a4f YY |
6973 | trace_create_file("saved_cmdlines_size", 0644, d_tracer, |
6974 | NULL, &tracing_saved_cmdlines_size_fops); | |
6975 | ||
0c564a53 SRRH |
6976 | trace_enum_init(); |
6977 | ||
9828413d SRRH |
6978 | trace_create_enum_file(d_tracer); |
6979 | ||
3673b8e4 SRRH |
6980 | #ifdef CONFIG_MODULES |
6981 | register_module_notifier(&trace_module_nb); | |
6982 | #endif | |
6983 | ||
bc0c38d1 | 6984 | #ifdef CONFIG_DYNAMIC_FTRACE |
5452af66 FW |
6985 | trace_create_file("dyn_ftrace_total_info", 0444, d_tracer, |
6986 | &ftrace_update_tot_cnt, &tracing_dyn_info_fops); | |
bc0c38d1 | 6987 | #endif |
b04cc6b1 | 6988 | |
277ba044 | 6989 | create_trace_instances(d_tracer); |
5452af66 | 6990 | |
37aea98b | 6991 | update_tracer_options(&global_trace); |
09d23a1d | 6992 | |
b5ad384e | 6993 | return 0; |
bc0c38d1 SR |
6994 | } |
6995 | ||
3f5a54e3 SR |
6996 | static int trace_panic_handler(struct notifier_block *this, |
6997 | unsigned long event, void *unused) | |
6998 | { | |
944ac425 | 6999 | if (ftrace_dump_on_oops) |
cecbca96 | 7000 | ftrace_dump(ftrace_dump_on_oops); |
3f5a54e3 SR |
7001 | return NOTIFY_OK; |
7002 | } | |
7003 | ||
7004 | static struct notifier_block trace_panic_notifier = { | |
7005 | .notifier_call = trace_panic_handler, | |
7006 | .next = NULL, | |
7007 | .priority = 150 /* priority: INT_MAX >= x >= 0 */ | |
7008 | }; | |
7009 | ||
7010 | static int trace_die_handler(struct notifier_block *self, | |
7011 | unsigned long val, | |
7012 | void *data) | |
7013 | { | |
7014 | switch (val) { | |
7015 | case DIE_OOPS: | |
944ac425 | 7016 | if (ftrace_dump_on_oops) |
cecbca96 | 7017 | ftrace_dump(ftrace_dump_on_oops); |
3f5a54e3 SR |
7018 | break; |
7019 | default: | |
7020 | break; | |
7021 | } | |
7022 | return NOTIFY_OK; | |
7023 | } | |
7024 | ||
7025 | static struct notifier_block trace_die_notifier = { | |
7026 | .notifier_call = trace_die_handler, | |
7027 | .priority = 200 | |
7028 | }; | |
7029 | ||
7030 | /* | |
7031 | * printk is set to max of 1024, we really don't need it that big. | |
7032 | * Nothing should be printing 1000 characters anyway. | |
7033 | */ | |
7034 | #define TRACE_MAX_PRINT 1000 | |
7035 | ||
7036 | /* | |
7037 | * Define here KERN_TRACE so that we have one place to modify | |
7038 | * it if we decide to change what log level the ftrace dump | |
7039 | * should be at. | |
7040 | */ | |
428aee14 | 7041 | #define KERN_TRACE KERN_EMERG |
3f5a54e3 | 7042 | |
955b61e5 | 7043 | void |
3f5a54e3 SR |
7044 | trace_printk_seq(struct trace_seq *s) |
7045 | { | |
7046 | /* Probably should print a warning here. */ | |
3a161d99 SRRH |
7047 | if (s->seq.len >= TRACE_MAX_PRINT) |
7048 | s->seq.len = TRACE_MAX_PRINT; | |
3f5a54e3 | 7049 | |
820b75f6 SRRH |
7050 | /* |
7051 | * More paranoid code. Although the buffer size is set to | |
7052 | * PAGE_SIZE, and TRACE_MAX_PRINT is 1000, this is just | |
7053 | * an extra layer of protection. | |
7054 | */ | |
7055 | if (WARN_ON_ONCE(s->seq.len >= s->seq.size)) | |
7056 | s->seq.len = s->seq.size - 1; | |
3f5a54e3 SR |
7057 | |
7058 | /* should be zero ended, but we are paranoid. */ | |
3a161d99 | 7059 | s->buffer[s->seq.len] = 0; |
3f5a54e3 SR |
7060 | |
7061 | printk(KERN_TRACE "%s", s->buffer); | |
7062 | ||
f9520750 | 7063 | trace_seq_init(s); |
3f5a54e3 SR |
7064 | } |
7065 | ||
955b61e5 JW |
7066 | void trace_init_global_iter(struct trace_iterator *iter) |
7067 | { | |
7068 | iter->tr = &global_trace; | |
2b6080f2 | 7069 | iter->trace = iter->tr->current_trace; |
ae3b5093 | 7070 | iter->cpu_file = RING_BUFFER_ALL_CPUS; |
12883efb | 7071 | iter->trace_buffer = &global_trace.trace_buffer; |
b2f974d6 CS |
7072 | |
7073 | if (iter->trace && iter->trace->open) | |
7074 | iter->trace->open(iter); | |
7075 | ||
7076 | /* Annotate start of buffers if we had overruns */ | |
7077 | if (ring_buffer_overruns(iter->trace_buffer->buffer)) | |
7078 | iter->iter_flags |= TRACE_FILE_ANNOTATE; | |
7079 | ||
7080 | /* Output in nanoseconds only if we are using a clock in nanoseconds. */ | |
7081 | if (trace_clocks[iter->tr->clock_id].in_ns) | |
7082 | iter->iter_flags |= TRACE_FILE_TIME_IN_NS; | |
955b61e5 JW |
7083 | } |
7084 | ||
7fe70b57 | 7085 | void ftrace_dump(enum ftrace_dump_mode oops_dump_mode) |
3f5a54e3 | 7086 | { |
3f5a54e3 SR |
7087 | /* use static because iter can be a bit big for the stack */ |
7088 | static struct trace_iterator iter; | |
7fe70b57 | 7089 | static atomic_t dump_running; |
983f938a | 7090 | struct trace_array *tr = &global_trace; |
cf586b61 | 7091 | unsigned int old_userobj; |
d769041f SR |
7092 | unsigned long flags; |
7093 | int cnt = 0, cpu; | |
3f5a54e3 | 7094 | |
7fe70b57 SRRH |
7095 | /* Only allow one dump user at a time. */ |
7096 | if (atomic_inc_return(&dump_running) != 1) { | |
7097 | atomic_dec(&dump_running); | |
7098 | return; | |
7099 | } | |
3f5a54e3 | 7100 | |
7fe70b57 SRRH |
7101 | /* |
7102 | * Always turn off tracing when we dump. | |
7103 | * We don't need to show trace output of what happens | |
7104 | * between multiple crashes. | |
7105 | * | |
7106 | * If the user does a sysrq-z, then they can re-enable | |
7107 | * tracing with echo 1 > tracing_on. | |
7108 | */ | |
0ee6b6cf | 7109 | tracing_off(); |
cf586b61 | 7110 | |
7fe70b57 | 7111 | local_irq_save(flags); |
3f5a54e3 | 7112 | |
38dbe0b1 | 7113 | /* Simulate the iterator */ |
955b61e5 JW |
7114 | trace_init_global_iter(&iter); |
7115 | ||
d769041f | 7116 | for_each_tracing_cpu(cpu) { |
5e2d5ef8 | 7117 | atomic_inc(&per_cpu_ptr(iter.trace_buffer->data, cpu)->disabled); |
d769041f SR |
7118 | } |
7119 | ||
983f938a | 7120 | old_userobj = tr->trace_flags & TRACE_ITER_SYM_USEROBJ; |
cf586b61 | 7121 | |
b54d3de9 | 7122 | /* don't look at user memory in panic mode */ |
983f938a | 7123 | tr->trace_flags &= ~TRACE_ITER_SYM_USEROBJ; |
b54d3de9 | 7124 | |
cecbca96 FW |
7125 | switch (oops_dump_mode) { |
7126 | case DUMP_ALL: | |
ae3b5093 | 7127 | iter.cpu_file = RING_BUFFER_ALL_CPUS; |
cecbca96 FW |
7128 | break; |
7129 | case DUMP_ORIG: | |
7130 | iter.cpu_file = raw_smp_processor_id(); | |
7131 | break; | |
7132 | case DUMP_NONE: | |
7133 | goto out_enable; | |
7134 | default: | |
7135 | printk(KERN_TRACE "Bad dumping mode, switching to all CPUs dump\n"); | |
ae3b5093 | 7136 | iter.cpu_file = RING_BUFFER_ALL_CPUS; |
cecbca96 FW |
7137 | } |
7138 | ||
7139 | printk(KERN_TRACE "Dumping ftrace buffer:\n"); | |
3f5a54e3 | 7140 | |
7fe70b57 SRRH |
7141 | /* Did function tracer already get disabled? */ |
7142 | if (ftrace_is_dead()) { | |
7143 | printk("# WARNING: FUNCTION TRACING IS CORRUPTED\n"); | |
7144 | printk("# MAY BE MISSING FUNCTION EVENTS\n"); | |
7145 | } | |
7146 | ||
3f5a54e3 SR |
7147 | /* |
7148 | * We need to stop all tracing on all CPUS to read the | |
7149 | * the next buffer. This is a bit expensive, but is | |
7150 | * not done often. We fill all what we can read, | |
7151 | * and then release the locks again. | |
7152 | */ | |
7153 | ||
3f5a54e3 SR |
7154 | while (!trace_empty(&iter)) { |
7155 | ||
7156 | if (!cnt) | |
7157 | printk(KERN_TRACE "---------------------------------\n"); | |
7158 | ||
7159 | cnt++; | |
7160 | ||
7161 | /* reset all but tr, trace, and overruns */ | |
7162 | memset(&iter.seq, 0, | |
7163 | sizeof(struct trace_iterator) - | |
7164 | offsetof(struct trace_iterator, seq)); | |
7165 | iter.iter_flags |= TRACE_FILE_LAT_FMT; | |
7166 | iter.pos = -1; | |
7167 | ||
955b61e5 | 7168 | if (trace_find_next_entry_inc(&iter) != NULL) { |
74e7ff8c LJ |
7169 | int ret; |
7170 | ||
7171 | ret = print_trace_line(&iter); | |
7172 | if (ret != TRACE_TYPE_NO_CONSUME) | |
7173 | trace_consume(&iter); | |
3f5a54e3 | 7174 | } |
b892e5c8 | 7175 | touch_nmi_watchdog(); |
3f5a54e3 SR |
7176 | |
7177 | trace_printk_seq(&iter.seq); | |
7178 | } | |
7179 | ||
7180 | if (!cnt) | |
7181 | printk(KERN_TRACE " (ftrace buffer empty)\n"); | |
7182 | else | |
7183 | printk(KERN_TRACE "---------------------------------\n"); | |
7184 | ||
cecbca96 | 7185 | out_enable: |
983f938a | 7186 | tr->trace_flags |= old_userobj; |
cf586b61 | 7187 | |
7fe70b57 SRRH |
7188 | for_each_tracing_cpu(cpu) { |
7189 | atomic_dec(&per_cpu_ptr(iter.trace_buffer->data, cpu)->disabled); | |
cf586b61 | 7190 | } |
7fe70b57 | 7191 | atomic_dec(&dump_running); |
cd891ae0 | 7192 | local_irq_restore(flags); |
3f5a54e3 | 7193 | } |
a8eecf22 | 7194 | EXPORT_SYMBOL_GPL(ftrace_dump); |
cf586b61 | 7195 | |
3928a8a2 | 7196 | __init static int tracer_alloc_buffers(void) |
bc0c38d1 | 7197 | { |
73c5162a | 7198 | int ring_buf_size; |
9e01c1b7 | 7199 | int ret = -ENOMEM; |
4c11d7ae | 7200 | |
b5e87c05 SRRH |
7201 | /* |
7202 | * Make sure we don't accidently add more trace options | |
7203 | * than we have bits for. | |
7204 | */ | |
9a38a885 | 7205 | BUILD_BUG_ON(TRACE_ITER_LAST_BIT > TRACE_FLAGS_MAX_SIZE); |
b5e87c05 | 7206 | |
9e01c1b7 RR |
7207 | if (!alloc_cpumask_var(&tracing_buffer_mask, GFP_KERNEL)) |
7208 | goto out; | |
7209 | ||
ccfe9e42 | 7210 | if (!alloc_cpumask_var(&global_trace.tracing_cpumask, GFP_KERNEL)) |
9e01c1b7 | 7211 | goto out_free_buffer_mask; |
4c11d7ae | 7212 | |
07d777fe SR |
7213 | /* Only allocate trace_printk buffers if a trace_printk exists */ |
7214 | if (__stop___trace_bprintk_fmt != __start___trace_bprintk_fmt) | |
81698831 | 7215 | /* Must be called before global_trace.buffer is allocated */ |
07d777fe SR |
7216 | trace_printk_init_buffers(); |
7217 | ||
73c5162a SR |
7218 | /* To save memory, keep the ring buffer size to its minimum */ |
7219 | if (ring_buffer_expanded) | |
7220 | ring_buf_size = trace_buf_size; | |
7221 | else | |
7222 | ring_buf_size = 1; | |
7223 | ||
9e01c1b7 | 7224 | cpumask_copy(tracing_buffer_mask, cpu_possible_mask); |
ccfe9e42 | 7225 | cpumask_copy(global_trace.tracing_cpumask, cpu_all_mask); |
9e01c1b7 | 7226 | |
2b6080f2 SR |
7227 | raw_spin_lock_init(&global_trace.start_lock); |
7228 | ||
2c4a33ab SRRH |
7229 | /* Used for event triggers */ |
7230 | temp_buffer = ring_buffer_alloc(PAGE_SIZE, RB_FL_OVERWRITE); | |
7231 | if (!temp_buffer) | |
7232 | goto out_free_cpumask; | |
7233 | ||
939c7a4f YY |
7234 | if (trace_create_savedcmd() < 0) |
7235 | goto out_free_temp_buffer; | |
7236 | ||
9e01c1b7 | 7237 | /* TODO: make the number of buffers hot pluggable with CPUS */ |
737223fb | 7238 | if (allocate_trace_buffers(&global_trace, ring_buf_size) < 0) { |
3928a8a2 SR |
7239 | printk(KERN_ERR "tracer: failed to allocate ring buffer!\n"); |
7240 | WARN_ON(1); | |
939c7a4f | 7241 | goto out_free_savedcmd; |
4c11d7ae | 7242 | } |
a7603ff4 | 7243 | |
499e5470 SR |
7244 | if (global_trace.buffer_disabled) |
7245 | tracing_off(); | |
4c11d7ae | 7246 | |
e1e232ca SR |
7247 | if (trace_boot_clock) { |
7248 | ret = tracing_set_clock(&global_trace, trace_boot_clock); | |
7249 | if (ret < 0) | |
7250 | pr_warning("Trace clock %s not defined, going back to default\n", | |
7251 | trace_boot_clock); | |
7252 | } | |
7253 | ||
ca164318 SRRH |
7254 | /* |
7255 | * register_tracer() might reference current_trace, so it | |
7256 | * needs to be set before we register anything. This is | |
7257 | * just a bootstrap of current_trace anyway. | |
7258 | */ | |
2b6080f2 SR |
7259 | global_trace.current_trace = &nop_trace; |
7260 | ||
0b9b12c1 SRRH |
7261 | global_trace.max_lock = (arch_spinlock_t)__ARCH_SPIN_LOCK_UNLOCKED; |
7262 | ||
4104d326 SRRH |
7263 | ftrace_init_global_array_ops(&global_trace); |
7264 | ||
9a38a885 SRRH |
7265 | init_trace_flags_index(&global_trace); |
7266 | ||
ca164318 SRRH |
7267 | register_tracer(&nop_trace); |
7268 | ||
60a11774 SR |
7269 | /* All seems OK, enable tracing */ |
7270 | tracing_disabled = 0; | |
3928a8a2 | 7271 | |
3f5a54e3 SR |
7272 | atomic_notifier_chain_register(&panic_notifier_list, |
7273 | &trace_panic_notifier); | |
7274 | ||
7275 | register_die_notifier(&trace_die_notifier); | |
2fc1dfbe | 7276 | |
ae63b31e SR |
7277 | global_trace.flags = TRACE_ARRAY_FL_GLOBAL; |
7278 | ||
7279 | INIT_LIST_HEAD(&global_trace.systems); | |
7280 | INIT_LIST_HEAD(&global_trace.events); | |
7281 | list_add(&global_trace.list, &ftrace_trace_arrays); | |
7282 | ||
a4d1e688 | 7283 | apply_trace_boot_options(); |
7bcfaf54 | 7284 | |
77fd5c15 SRRH |
7285 | register_snapshot_cmd(); |
7286 | ||
2fc1dfbe | 7287 | return 0; |
3f5a54e3 | 7288 | |
939c7a4f YY |
7289 | out_free_savedcmd: |
7290 | free_saved_cmdlines_buffer(savedcmd); | |
2c4a33ab SRRH |
7291 | out_free_temp_buffer: |
7292 | ring_buffer_free(temp_buffer); | |
9e01c1b7 | 7293 | out_free_cpumask: |
ccfe9e42 | 7294 | free_cpumask_var(global_trace.tracing_cpumask); |
9e01c1b7 RR |
7295 | out_free_buffer_mask: |
7296 | free_cpumask_var(tracing_buffer_mask); | |
7297 | out: | |
7298 | return ret; | |
bc0c38d1 | 7299 | } |
b2821ae6 | 7300 | |
5f893b26 SRRH |
7301 | void __init trace_init(void) |
7302 | { | |
0daa2302 SRRH |
7303 | if (tracepoint_printk) { |
7304 | tracepoint_print_iter = | |
7305 | kmalloc(sizeof(*tracepoint_print_iter), GFP_KERNEL); | |
7306 | if (WARN_ON(!tracepoint_print_iter)) | |
7307 | tracepoint_printk = 0; | |
7308 | } | |
5f893b26 | 7309 | tracer_alloc_buffers(); |
0c564a53 | 7310 | trace_event_init(); |
5f893b26 SRRH |
7311 | } |
7312 | ||
b2821ae6 SR |
7313 | __init static int clear_boot_tracer(void) |
7314 | { | |
7315 | /* | |
7316 | * The default tracer at boot buffer is an init section. | |
7317 | * This function is called in lateinit. If we did not | |
7318 | * find the boot tracer, then clear it out, to prevent | |
7319 | * later registration from accessing the buffer that is | |
7320 | * about to be freed. | |
7321 | */ | |
7322 | if (!default_bootup_tracer) | |
7323 | return 0; | |
7324 | ||
7325 | printk(KERN_INFO "ftrace bootup tracer '%s' not registered.\n", | |
7326 | default_bootup_tracer); | |
7327 | default_bootup_tracer = NULL; | |
7328 | ||
7329 | return 0; | |
7330 | } | |
7331 | ||
8434dc93 | 7332 | fs_initcall(tracer_init_tracefs); |
b2821ae6 | 7333 | late_initcall(clear_boot_tracer); |