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