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