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> |
4c11d7ae | 23 | #include <linux/pagemap.h> |
bc0c38d1 SR |
24 | #include <linux/hardirq.h> |
25 | #include <linux/linkage.h> | |
26 | #include <linux/uaccess.h> | |
2cadf913 | 27 | #include <linux/kprobes.h> |
bc0c38d1 SR |
28 | #include <linux/ftrace.h> |
29 | #include <linux/module.h> | |
30 | #include <linux/percpu.h> | |
2cadf913 | 31 | #include <linux/splice.h> |
3f5a54e3 | 32 | #include <linux/kdebug.h> |
5f0c6c03 | 33 | #include <linux/string.h> |
7e53bd42 | 34 | #include <linux/rwsem.h> |
5a0e3ad6 | 35 | #include <linux/slab.h> |
bc0c38d1 SR |
36 | #include <linux/ctype.h> |
37 | #include <linux/init.h> | |
2a2cc8f7 | 38 | #include <linux/poll.h> |
b892e5c8 | 39 | #include <linux/nmi.h> |
bc0c38d1 | 40 | #include <linux/fs.h> |
8bd75c77 | 41 | #include <linux/sched/rt.h> |
86387f7e | 42 | |
bc0c38d1 | 43 | #include "trace.h" |
f0868d1e | 44 | #include "trace_output.h" |
bc0c38d1 | 45 | |
73c5162a SR |
46 | /* |
47 | * On boot up, the ring buffer is set to the minimum size, so that | |
48 | * we do not waste memory on systems that are not using tracing. | |
49 | */ | |
55034cd6 | 50 | bool ring_buffer_expanded; |
73c5162a | 51 | |
8e1b82e0 FW |
52 | /* |
53 | * We need to change this state when a selftest is running. | |
ff32504f FW |
54 | * A selftest will lurk into the ring-buffer to count the |
55 | * entries inserted during the selftest although some concurrent | |
5e1607a0 | 56 | * insertions into the ring-buffer such as trace_printk could occurred |
ff32504f FW |
57 | * at the same time, giving false positive or negative results. |
58 | */ | |
8e1b82e0 | 59 | static bool __read_mostly tracing_selftest_running; |
ff32504f | 60 | |
b2821ae6 SR |
61 | /* |
62 | * If a tracer is running, we do not want to run SELFTEST. | |
63 | */ | |
020e5f85 | 64 | bool __read_mostly tracing_selftest_disabled; |
b2821ae6 | 65 | |
adf9f195 FW |
66 | /* For tracers that don't implement custom flags */ |
67 | static struct tracer_opt dummy_tracer_opt[] = { | |
68 | { } | |
69 | }; | |
70 | ||
71 | static struct tracer_flags dummy_tracer_flags = { | |
72 | .val = 0, | |
73 | .opts = dummy_tracer_opt | |
74 | }; | |
75 | ||
76 | static int dummy_set_flag(u32 old_flags, u32 bit, int set) | |
77 | { | |
78 | return 0; | |
79 | } | |
0f048701 | 80 | |
7ffbd48d SR |
81 | /* |
82 | * To prevent the comm cache from being overwritten when no | |
83 | * tracing is active, only save the comm when a trace event | |
84 | * occurred. | |
85 | */ | |
86 | static DEFINE_PER_CPU(bool, trace_cmdline_save); | |
87 | ||
0f048701 SR |
88 | /* |
89 | * Kill all tracing for good (never come back). | |
90 | * It is initialized to 1 but will turn to zero if the initialization | |
91 | * of the tracer is successful. But that is the only place that sets | |
92 | * this back to zero. | |
93 | */ | |
4fd27358 | 94 | static int tracing_disabled = 1; |
0f048701 | 95 | |
9288f99a | 96 | DEFINE_PER_CPU(int, ftrace_cpu_disabled); |
d769041f | 97 | |
955b61e5 | 98 | cpumask_var_t __read_mostly tracing_buffer_mask; |
ab46428c | 99 | |
944ac425 SR |
100 | /* |
101 | * ftrace_dump_on_oops - variable to dump ftrace buffer on oops | |
102 | * | |
103 | * If there is an oops (or kernel panic) and the ftrace_dump_on_oops | |
104 | * is set, then ftrace_dump is called. This will output the contents | |
105 | * of the ftrace buffers to the console. This is very useful for | |
106 | * capturing traces that lead to crashes and outputing it to a | |
107 | * serial console. | |
108 | * | |
109 | * It is default off, but you can enable it with either specifying | |
110 | * "ftrace_dump_on_oops" in the kernel command line, or setting | |
cecbca96 FW |
111 | * /proc/sys/kernel/ftrace_dump_on_oops |
112 | * Set 1 if you want to dump buffers of all CPUs | |
113 | * Set 2 if you want to dump the buffer of the CPU that triggered oops | |
944ac425 | 114 | */ |
cecbca96 FW |
115 | |
116 | enum ftrace_dump_mode ftrace_dump_on_oops; | |
944ac425 | 117 | |
de7edd31 SRRH |
118 | /* When set, tracing will stop when a WARN*() is hit */ |
119 | int __disable_trace_on_warning; | |
120 | ||
b2821ae6 SR |
121 | static int tracing_set_tracer(const char *buf); |
122 | ||
ee6c2c1b LZ |
123 | #define MAX_TRACER_SIZE 100 |
124 | static char bootup_tracer_buf[MAX_TRACER_SIZE] __initdata; | |
b2821ae6 | 125 | static char *default_bootup_tracer; |
d9e54076 | 126 | |
55034cd6 SRRH |
127 | static bool allocate_snapshot; |
128 | ||
1beee96b | 129 | static int __init set_cmdline_ftrace(char *str) |
d9e54076 | 130 | { |
67012ab1 | 131 | strlcpy(bootup_tracer_buf, str, MAX_TRACER_SIZE); |
b2821ae6 | 132 | default_bootup_tracer = bootup_tracer_buf; |
73c5162a | 133 | /* We are using ftrace early, expand it */ |
55034cd6 | 134 | ring_buffer_expanded = true; |
d9e54076 PZ |
135 | return 1; |
136 | } | |
1beee96b | 137 | __setup("ftrace=", set_cmdline_ftrace); |
d9e54076 | 138 | |
944ac425 SR |
139 | static int __init set_ftrace_dump_on_oops(char *str) |
140 | { | |
cecbca96 FW |
141 | if (*str++ != '=' || !*str) { |
142 | ftrace_dump_on_oops = DUMP_ALL; | |
143 | return 1; | |
144 | } | |
145 | ||
146 | if (!strcmp("orig_cpu", str)) { | |
147 | ftrace_dump_on_oops = DUMP_ORIG; | |
148 | return 1; | |
149 | } | |
150 | ||
151 | return 0; | |
944ac425 SR |
152 | } |
153 | __setup("ftrace_dump_on_oops", set_ftrace_dump_on_oops); | |
60a11774 | 154 | |
de7edd31 SRRH |
155 | static int __init stop_trace_on_warning(char *str) |
156 | { | |
157 | __disable_trace_on_warning = 1; | |
158 | return 1; | |
159 | } | |
160 | __setup("traceoff_on_warning=", stop_trace_on_warning); | |
161 | ||
3209cff4 | 162 | static int __init boot_alloc_snapshot(char *str) |
55034cd6 SRRH |
163 | { |
164 | allocate_snapshot = true; | |
165 | /* We also need the main ring buffer expanded */ | |
166 | ring_buffer_expanded = true; | |
167 | return 1; | |
168 | } | |
3209cff4 | 169 | __setup("alloc_snapshot", boot_alloc_snapshot); |
55034cd6 | 170 | |
7bcfaf54 SR |
171 | |
172 | static char trace_boot_options_buf[MAX_TRACER_SIZE] __initdata; | |
173 | static char *trace_boot_options __initdata; | |
174 | ||
175 | static int __init set_trace_boot_options(char *str) | |
176 | { | |
67012ab1 | 177 | strlcpy(trace_boot_options_buf, str, MAX_TRACER_SIZE); |
7bcfaf54 SR |
178 | trace_boot_options = trace_boot_options_buf; |
179 | return 0; | |
180 | } | |
181 | __setup("trace_options=", set_trace_boot_options); | |
182 | ||
de7edd31 | 183 | |
cf8e3474 | 184 | unsigned long long ns2usecs(cycle_t nsec) |
bc0c38d1 SR |
185 | { |
186 | nsec += 500; | |
187 | do_div(nsec, 1000); | |
188 | return nsec; | |
189 | } | |
190 | ||
4fcdae83 SR |
191 | /* |
192 | * The global_trace is the descriptor that holds the tracing | |
193 | * buffers for the live tracing. For each CPU, it contains | |
194 | * a link list of pages that will store trace entries. The | |
195 | * page descriptor of the pages in the memory is used to hold | |
196 | * the link list by linking the lru item in the page descriptor | |
197 | * to each of the pages in the buffer per CPU. | |
198 | * | |
199 | * For each active CPU there is a data field that holds the | |
200 | * pages for the buffer for that CPU. Each CPU has the same number | |
201 | * of pages allocated for its buffer. | |
202 | */ | |
bc0c38d1 SR |
203 | static struct trace_array global_trace; |
204 | ||
ae63b31e | 205 | LIST_HEAD(ftrace_trace_arrays); |
bc0c38d1 | 206 | |
ff451961 SRRH |
207 | int trace_array_get(struct trace_array *this_tr) |
208 | { | |
209 | struct trace_array *tr; | |
210 | int ret = -ENODEV; | |
211 | ||
212 | mutex_lock(&trace_types_lock); | |
213 | list_for_each_entry(tr, &ftrace_trace_arrays, list) { | |
214 | if (tr == this_tr) { | |
215 | tr->ref++; | |
216 | ret = 0; | |
217 | break; | |
218 | } | |
219 | } | |
220 | mutex_unlock(&trace_types_lock); | |
221 | ||
222 | return ret; | |
223 | } | |
224 | ||
225 | static void __trace_array_put(struct trace_array *this_tr) | |
226 | { | |
227 | WARN_ON(!this_tr->ref); | |
228 | this_tr->ref--; | |
229 | } | |
230 | ||
231 | void trace_array_put(struct trace_array *this_tr) | |
232 | { | |
233 | mutex_lock(&trace_types_lock); | |
234 | __trace_array_put(this_tr); | |
235 | mutex_unlock(&trace_types_lock); | |
236 | } | |
237 | ||
e77405ad SR |
238 | int filter_current_check_discard(struct ring_buffer *buffer, |
239 | struct ftrace_event_call *call, void *rec, | |
eb02ce01 TZ |
240 | struct ring_buffer_event *event) |
241 | { | |
e77405ad | 242 | return filter_check_discard(call, rec, buffer, event); |
eb02ce01 | 243 | } |
17c873ec | 244 | EXPORT_SYMBOL_GPL(filter_current_check_discard); |
eb02ce01 | 245 | |
37886f6a SR |
246 | cycle_t ftrace_now(int cpu) |
247 | { | |
248 | u64 ts; | |
249 | ||
250 | /* Early boot up does not have a buffer yet */ | |
12883efb | 251 | if (!global_trace.trace_buffer.buffer) |
37886f6a SR |
252 | return trace_clock_local(); |
253 | ||
12883efb SRRH |
254 | ts = ring_buffer_time_stamp(global_trace.trace_buffer.buffer, cpu); |
255 | ring_buffer_normalize_time_stamp(global_trace.trace_buffer.buffer, cpu, &ts); | |
37886f6a SR |
256 | |
257 | return ts; | |
258 | } | |
bc0c38d1 | 259 | |
10246fa3 SRRH |
260 | /** |
261 | * tracing_is_enabled - Show if global_trace has been disabled | |
262 | * | |
263 | * Shows if the global trace has been enabled or not. It uses the | |
264 | * mirror flag "buffer_disabled" to be used in fast paths such as for | |
265 | * the irqsoff tracer. But it may be inaccurate due to races. If you | |
266 | * need to know the accurate state, use tracing_is_on() which is a little | |
267 | * slower, but accurate. | |
268 | */ | |
9036990d SR |
269 | int tracing_is_enabled(void) |
270 | { | |
10246fa3 SRRH |
271 | /* |
272 | * For quick access (irqsoff uses this in fast path), just | |
273 | * return the mirror variable of the state of the ring buffer. | |
274 | * It's a little racy, but we don't really care. | |
275 | */ | |
276 | smp_rmb(); | |
277 | return !global_trace.buffer_disabled; | |
9036990d SR |
278 | } |
279 | ||
4fcdae83 | 280 | /* |
3928a8a2 SR |
281 | * trace_buf_size is the size in bytes that is allocated |
282 | * for a buffer. Note, the number of bytes is always rounded | |
283 | * to page size. | |
3f5a54e3 SR |
284 | * |
285 | * This number is purposely set to a low number of 16384. | |
286 | * If the dump on oops happens, it will be much appreciated | |
287 | * to not have to wait for all that output. Anyway this can be | |
288 | * boot time and run time configurable. | |
4fcdae83 | 289 | */ |
3928a8a2 | 290 | #define TRACE_BUF_SIZE_DEFAULT 1441792UL /* 16384 * 88 (sizeof(entry)) */ |
3f5a54e3 | 291 | |
3928a8a2 | 292 | static unsigned long trace_buf_size = TRACE_BUF_SIZE_DEFAULT; |
bc0c38d1 | 293 | |
4fcdae83 | 294 | /* trace_types holds a link list of available tracers. */ |
bc0c38d1 | 295 | static struct tracer *trace_types __read_mostly; |
4fcdae83 | 296 | |
4fcdae83 SR |
297 | /* |
298 | * trace_types_lock is used to protect the trace_types list. | |
4fcdae83 | 299 | */ |
a8227415 | 300 | DEFINE_MUTEX(trace_types_lock); |
4fcdae83 | 301 | |
7e53bd42 LJ |
302 | /* |
303 | * serialize the access of the ring buffer | |
304 | * | |
305 | * ring buffer serializes readers, but it is low level protection. | |
306 | * The validity of the events (which returns by ring_buffer_peek() ..etc) | |
307 | * are not protected by ring buffer. | |
308 | * | |
309 | * The content of events may become garbage if we allow other process consumes | |
310 | * these events concurrently: | |
311 | * A) the page of the consumed events may become a normal page | |
312 | * (not reader page) in ring buffer, and this page will be rewrited | |
313 | * by events producer. | |
314 | * B) The page of the consumed events may become a page for splice_read, | |
315 | * and this page will be returned to system. | |
316 | * | |
317 | * These primitives allow multi process access to different cpu ring buffer | |
318 | * concurrently. | |
319 | * | |
320 | * These primitives don't distinguish read-only and read-consume access. | |
321 | * Multi read-only access are also serialized. | |
322 | */ | |
323 | ||
324 | #ifdef CONFIG_SMP | |
325 | static DECLARE_RWSEM(all_cpu_access_lock); | |
326 | static DEFINE_PER_CPU(struct mutex, cpu_access_lock); | |
327 | ||
328 | static inline void trace_access_lock(int cpu) | |
329 | { | |
ae3b5093 | 330 | if (cpu == RING_BUFFER_ALL_CPUS) { |
7e53bd42 LJ |
331 | /* gain it for accessing the whole ring buffer. */ |
332 | down_write(&all_cpu_access_lock); | |
333 | } else { | |
334 | /* gain it for accessing a cpu ring buffer. */ | |
335 | ||
ae3b5093 | 336 | /* Firstly block other trace_access_lock(RING_BUFFER_ALL_CPUS). */ |
7e53bd42 LJ |
337 | down_read(&all_cpu_access_lock); |
338 | ||
339 | /* Secondly block other access to this @cpu ring buffer. */ | |
340 | mutex_lock(&per_cpu(cpu_access_lock, cpu)); | |
341 | } | |
342 | } | |
343 | ||
344 | static inline void trace_access_unlock(int cpu) | |
345 | { | |
ae3b5093 | 346 | if (cpu == RING_BUFFER_ALL_CPUS) { |
7e53bd42 LJ |
347 | up_write(&all_cpu_access_lock); |
348 | } else { | |
349 | mutex_unlock(&per_cpu(cpu_access_lock, cpu)); | |
350 | up_read(&all_cpu_access_lock); | |
351 | } | |
352 | } | |
353 | ||
354 | static inline void trace_access_lock_init(void) | |
355 | { | |
356 | int cpu; | |
357 | ||
358 | for_each_possible_cpu(cpu) | |
359 | mutex_init(&per_cpu(cpu_access_lock, cpu)); | |
360 | } | |
361 | ||
362 | #else | |
363 | ||
364 | static DEFINE_MUTEX(access_lock); | |
365 | ||
366 | static inline void trace_access_lock(int cpu) | |
367 | { | |
368 | (void)cpu; | |
369 | mutex_lock(&access_lock); | |
370 | } | |
371 | ||
372 | static inline void trace_access_unlock(int cpu) | |
373 | { | |
374 | (void)cpu; | |
375 | mutex_unlock(&access_lock); | |
376 | } | |
377 | ||
378 | static inline void trace_access_lock_init(void) | |
379 | { | |
380 | } | |
381 | ||
382 | #endif | |
383 | ||
ee6bce52 | 384 | /* trace_flags holds trace_options default values */ |
12ef7d44 | 385 | unsigned long trace_flags = TRACE_ITER_PRINT_PARENT | TRACE_ITER_PRINTK | |
a2a16d6a | 386 | TRACE_ITER_ANNOTATE | TRACE_ITER_CONTEXT_INFO | TRACE_ITER_SLEEP_TIME | |
77271ce4 | 387 | TRACE_ITER_GRAPH_TIME | TRACE_ITER_RECORD_CMD | TRACE_ITER_OVERWRITE | |
328df475 | 388 | TRACE_ITER_IRQ_INFO | TRACE_ITER_MARKERS | TRACE_ITER_FUNCTION; |
e7e2ee89 | 389 | |
10246fa3 SRRH |
390 | void tracer_tracing_on(struct trace_array *tr) |
391 | { | |
392 | if (tr->trace_buffer.buffer) | |
393 | ring_buffer_record_on(tr->trace_buffer.buffer); | |
394 | /* | |
395 | * This flag is looked at when buffers haven't been allocated | |
396 | * yet, or by some tracers (like irqsoff), that just want to | |
397 | * know if the ring buffer has been disabled, but it can handle | |
398 | * races of where it gets disabled but we still do a record. | |
399 | * As the check is in the fast path of the tracers, it is more | |
400 | * important to be fast than accurate. | |
401 | */ | |
402 | tr->buffer_disabled = 0; | |
403 | /* Make the flag seen by readers */ | |
404 | smp_wmb(); | |
405 | } | |
406 | ||
499e5470 SR |
407 | /** |
408 | * tracing_on - enable tracing buffers | |
409 | * | |
410 | * This function enables tracing buffers that may have been | |
411 | * disabled with tracing_off. | |
412 | */ | |
413 | void tracing_on(void) | |
414 | { | |
10246fa3 | 415 | tracer_tracing_on(&global_trace); |
499e5470 SR |
416 | } |
417 | EXPORT_SYMBOL_GPL(tracing_on); | |
418 | ||
09ae7234 SRRH |
419 | /** |
420 | * __trace_puts - write a constant string into the trace buffer. | |
421 | * @ip: The address of the caller | |
422 | * @str: The constant string to write | |
423 | * @size: The size of the string. | |
424 | */ | |
425 | int __trace_puts(unsigned long ip, const char *str, int size) | |
426 | { | |
427 | struct ring_buffer_event *event; | |
428 | struct ring_buffer *buffer; | |
429 | struct print_entry *entry; | |
430 | unsigned long irq_flags; | |
431 | int alloc; | |
432 | ||
433 | alloc = sizeof(*entry) + size + 2; /* possible \n added */ | |
434 | ||
435 | local_save_flags(irq_flags); | |
436 | buffer = global_trace.trace_buffer.buffer; | |
437 | event = trace_buffer_lock_reserve(buffer, TRACE_PRINT, alloc, | |
438 | irq_flags, preempt_count()); | |
439 | if (!event) | |
440 | return 0; | |
441 | ||
442 | entry = ring_buffer_event_data(event); | |
443 | entry->ip = ip; | |
444 | ||
445 | memcpy(&entry->buf, str, size); | |
446 | ||
447 | /* Add a newline if necessary */ | |
448 | if (entry->buf[size - 1] != '\n') { | |
449 | entry->buf[size] = '\n'; | |
450 | entry->buf[size + 1] = '\0'; | |
451 | } else | |
452 | entry->buf[size] = '\0'; | |
453 | ||
454 | __buffer_unlock_commit(buffer, event); | |
455 | ||
456 | return size; | |
457 | } | |
458 | EXPORT_SYMBOL_GPL(__trace_puts); | |
459 | ||
460 | /** | |
461 | * __trace_bputs - write the pointer to a constant string into trace buffer | |
462 | * @ip: The address of the caller | |
463 | * @str: The constant string to write to the buffer to | |
464 | */ | |
465 | int __trace_bputs(unsigned long ip, const char *str) | |
466 | { | |
467 | struct ring_buffer_event *event; | |
468 | struct ring_buffer *buffer; | |
469 | struct bputs_entry *entry; | |
470 | unsigned long irq_flags; | |
471 | int size = sizeof(struct bputs_entry); | |
472 | ||
473 | local_save_flags(irq_flags); | |
474 | buffer = global_trace.trace_buffer.buffer; | |
475 | event = trace_buffer_lock_reserve(buffer, TRACE_BPUTS, size, | |
476 | irq_flags, preempt_count()); | |
477 | if (!event) | |
478 | return 0; | |
479 | ||
480 | entry = ring_buffer_event_data(event); | |
481 | entry->ip = ip; | |
482 | entry->str = str; | |
483 | ||
484 | __buffer_unlock_commit(buffer, event); | |
485 | ||
486 | return 1; | |
487 | } | |
488 | EXPORT_SYMBOL_GPL(__trace_bputs); | |
489 | ||
ad909e21 SRRH |
490 | #ifdef CONFIG_TRACER_SNAPSHOT |
491 | /** | |
492 | * trace_snapshot - take a snapshot of the current buffer. | |
493 | * | |
494 | * This causes a swap between the snapshot buffer and the current live | |
495 | * tracing buffer. You can use this to take snapshots of the live | |
496 | * trace when some condition is triggered, but continue to trace. | |
497 | * | |
498 | * Note, make sure to allocate the snapshot with either | |
499 | * a tracing_snapshot_alloc(), or by doing it manually | |
500 | * with: echo 1 > /sys/kernel/debug/tracing/snapshot | |
501 | * | |
502 | * If the snapshot buffer is not allocated, it will stop tracing. | |
503 | * Basically making a permanent snapshot. | |
504 | */ | |
505 | void tracing_snapshot(void) | |
506 | { | |
507 | struct trace_array *tr = &global_trace; | |
508 | struct tracer *tracer = tr->current_trace; | |
509 | unsigned long flags; | |
510 | ||
1b22e382 SRRH |
511 | if (in_nmi()) { |
512 | internal_trace_puts("*** SNAPSHOT CALLED FROM NMI CONTEXT ***\n"); | |
513 | internal_trace_puts("*** snapshot is being ignored ***\n"); | |
514 | return; | |
515 | } | |
516 | ||
ad909e21 | 517 | if (!tr->allocated_snapshot) { |
ca268da6 SRRH |
518 | internal_trace_puts("*** SNAPSHOT NOT ALLOCATED ***\n"); |
519 | internal_trace_puts("*** stopping trace here! ***\n"); | |
ad909e21 SRRH |
520 | tracing_off(); |
521 | return; | |
522 | } | |
523 | ||
524 | /* Note, snapshot can not be used when the tracer uses it */ | |
525 | if (tracer->use_max_tr) { | |
ca268da6 SRRH |
526 | internal_trace_puts("*** LATENCY TRACER ACTIVE ***\n"); |
527 | internal_trace_puts("*** Can not use snapshot (sorry) ***\n"); | |
ad909e21 SRRH |
528 | return; |
529 | } | |
530 | ||
531 | local_irq_save(flags); | |
532 | update_max_tr(tr, current, smp_processor_id()); | |
533 | local_irq_restore(flags); | |
534 | } | |
1b22e382 | 535 | EXPORT_SYMBOL_GPL(tracing_snapshot); |
ad909e21 SRRH |
536 | |
537 | static int resize_buffer_duplicate_size(struct trace_buffer *trace_buf, | |
538 | struct trace_buffer *size_buf, int cpu_id); | |
3209cff4 SRRH |
539 | static void set_buffer_entries(struct trace_buffer *buf, unsigned long val); |
540 | ||
541 | static int alloc_snapshot(struct trace_array *tr) | |
542 | { | |
543 | int ret; | |
544 | ||
545 | if (!tr->allocated_snapshot) { | |
546 | ||
547 | /* allocate spare buffer */ | |
548 | ret = resize_buffer_duplicate_size(&tr->max_buffer, | |
549 | &tr->trace_buffer, RING_BUFFER_ALL_CPUS); | |
550 | if (ret < 0) | |
551 | return ret; | |
552 | ||
553 | tr->allocated_snapshot = true; | |
554 | } | |
555 | ||
556 | return 0; | |
557 | } | |
558 | ||
559 | void free_snapshot(struct trace_array *tr) | |
560 | { | |
561 | /* | |
562 | * We don't free the ring buffer. instead, resize it because | |
563 | * The max_tr ring buffer has some state (e.g. ring->clock) and | |
564 | * we want preserve it. | |
565 | */ | |
566 | ring_buffer_resize(tr->max_buffer.buffer, 1, RING_BUFFER_ALL_CPUS); | |
567 | set_buffer_entries(&tr->max_buffer, 1); | |
568 | tracing_reset_online_cpus(&tr->max_buffer); | |
569 | tr->allocated_snapshot = false; | |
570 | } | |
ad909e21 SRRH |
571 | |
572 | /** | |
573 | * trace_snapshot_alloc - allocate and take a snapshot of the current buffer. | |
574 | * | |
575 | * This is similar to trace_snapshot(), but it will allocate the | |
576 | * snapshot buffer if it isn't already allocated. Use this only | |
577 | * where it is safe to sleep, as the allocation may sleep. | |
578 | * | |
579 | * This causes a swap between the snapshot buffer and the current live | |
580 | * tracing buffer. You can use this to take snapshots of the live | |
581 | * trace when some condition is triggered, but continue to trace. | |
582 | */ | |
583 | void tracing_snapshot_alloc(void) | |
584 | { | |
585 | struct trace_array *tr = &global_trace; | |
586 | int ret; | |
587 | ||
3209cff4 SRRH |
588 | ret = alloc_snapshot(tr); |
589 | if (WARN_ON(ret < 0)) | |
590 | return; | |
ad909e21 SRRH |
591 | |
592 | tracing_snapshot(); | |
593 | } | |
1b22e382 | 594 | EXPORT_SYMBOL_GPL(tracing_snapshot_alloc); |
ad909e21 SRRH |
595 | #else |
596 | void tracing_snapshot(void) | |
597 | { | |
598 | WARN_ONCE(1, "Snapshot feature not enabled, but internal snapshot used"); | |
599 | } | |
1b22e382 | 600 | EXPORT_SYMBOL_GPL(tracing_snapshot); |
ad909e21 SRRH |
601 | void tracing_snapshot_alloc(void) |
602 | { | |
603 | /* Give warning */ | |
604 | tracing_snapshot(); | |
605 | } | |
1b22e382 | 606 | EXPORT_SYMBOL_GPL(tracing_snapshot_alloc); |
ad909e21 SRRH |
607 | #endif /* CONFIG_TRACER_SNAPSHOT */ |
608 | ||
10246fa3 SRRH |
609 | void tracer_tracing_off(struct trace_array *tr) |
610 | { | |
611 | if (tr->trace_buffer.buffer) | |
612 | ring_buffer_record_off(tr->trace_buffer.buffer); | |
613 | /* | |
614 | * This flag is looked at when buffers haven't been allocated | |
615 | * yet, or by some tracers (like irqsoff), that just want to | |
616 | * know if the ring buffer has been disabled, but it can handle | |
617 | * races of where it gets disabled but we still do a record. | |
618 | * As the check is in the fast path of the tracers, it is more | |
619 | * important to be fast than accurate. | |
620 | */ | |
621 | tr->buffer_disabled = 1; | |
622 | /* Make the flag seen by readers */ | |
623 | smp_wmb(); | |
624 | } | |
625 | ||
499e5470 SR |
626 | /** |
627 | * tracing_off - turn off tracing buffers | |
628 | * | |
629 | * This function stops the tracing buffers from recording data. | |
630 | * It does not disable any overhead the tracers themselves may | |
631 | * be causing. This function simply causes all recording to | |
632 | * the ring buffers to fail. | |
633 | */ | |
634 | void tracing_off(void) | |
635 | { | |
10246fa3 | 636 | tracer_tracing_off(&global_trace); |
499e5470 SR |
637 | } |
638 | EXPORT_SYMBOL_GPL(tracing_off); | |
639 | ||
de7edd31 SRRH |
640 | void disable_trace_on_warning(void) |
641 | { | |
642 | if (__disable_trace_on_warning) | |
643 | tracing_off(); | |
644 | } | |
645 | ||
10246fa3 SRRH |
646 | /** |
647 | * tracer_tracing_is_on - show real state of ring buffer enabled | |
648 | * @tr : the trace array to know if ring buffer is enabled | |
649 | * | |
650 | * Shows real state of the ring buffer if it is enabled or not. | |
651 | */ | |
652 | int tracer_tracing_is_on(struct trace_array *tr) | |
653 | { | |
654 | if (tr->trace_buffer.buffer) | |
655 | return ring_buffer_record_is_on(tr->trace_buffer.buffer); | |
656 | return !tr->buffer_disabled; | |
657 | } | |
658 | ||
499e5470 SR |
659 | /** |
660 | * tracing_is_on - show state of ring buffers enabled | |
661 | */ | |
662 | int tracing_is_on(void) | |
663 | { | |
10246fa3 | 664 | return tracer_tracing_is_on(&global_trace); |
499e5470 SR |
665 | } |
666 | EXPORT_SYMBOL_GPL(tracing_is_on); | |
667 | ||
3928a8a2 | 668 | static int __init set_buf_size(char *str) |
bc0c38d1 | 669 | { |
3928a8a2 | 670 | unsigned long buf_size; |
c6caeeb1 | 671 | |
bc0c38d1 SR |
672 | if (!str) |
673 | return 0; | |
9d612bef | 674 | buf_size = memparse(str, &str); |
c6caeeb1 | 675 | /* nr_entries can not be zero */ |
9d612bef | 676 | if (buf_size == 0) |
c6caeeb1 | 677 | return 0; |
3928a8a2 | 678 | trace_buf_size = buf_size; |
bc0c38d1 SR |
679 | return 1; |
680 | } | |
3928a8a2 | 681 | __setup("trace_buf_size=", set_buf_size); |
bc0c38d1 | 682 | |
0e950173 TB |
683 | static int __init set_tracing_thresh(char *str) |
684 | { | |
87abb3b1 | 685 | unsigned long threshold; |
0e950173 TB |
686 | int ret; |
687 | ||
688 | if (!str) | |
689 | return 0; | |
bcd83ea6 | 690 | ret = kstrtoul(str, 0, &threshold); |
0e950173 TB |
691 | if (ret < 0) |
692 | return 0; | |
87abb3b1 | 693 | tracing_thresh = threshold * 1000; |
0e950173 TB |
694 | return 1; |
695 | } | |
696 | __setup("tracing_thresh=", set_tracing_thresh); | |
697 | ||
57f50be1 SR |
698 | unsigned long nsecs_to_usecs(unsigned long nsecs) |
699 | { | |
700 | return nsecs / 1000; | |
701 | } | |
702 | ||
4fcdae83 | 703 | /* These must match the bit postions in trace_iterator_flags */ |
bc0c38d1 SR |
704 | static const char *trace_options[] = { |
705 | "print-parent", | |
706 | "sym-offset", | |
707 | "sym-addr", | |
708 | "verbose", | |
f9896bf3 | 709 | "raw", |
5e3ca0ec | 710 | "hex", |
cb0f12aa | 711 | "bin", |
2a2cc8f7 | 712 | "block", |
86387f7e | 713 | "stacktrace", |
5e1607a0 | 714 | "trace_printk", |
b2a866f9 | 715 | "ftrace_preempt", |
9f029e83 | 716 | "branch", |
12ef7d44 | 717 | "annotate", |
02b67518 | 718 | "userstacktrace", |
b54d3de9 | 719 | "sym-userobj", |
66896a85 | 720 | "printk-msg-only", |
c4a8e8be | 721 | "context-info", |
c032ef64 | 722 | "latency-format", |
be6f164a | 723 | "sleep-time", |
a2a16d6a | 724 | "graph-time", |
e870e9a1 | 725 | "record-cmd", |
750912fa | 726 | "overwrite", |
cf30cf67 | 727 | "disable_on_free", |
77271ce4 | 728 | "irq-info", |
5224c3a3 | 729 | "markers", |
328df475 | 730 | "function-trace", |
bc0c38d1 SR |
731 | NULL |
732 | }; | |
733 | ||
5079f326 Z |
734 | static struct { |
735 | u64 (*func)(void); | |
736 | const char *name; | |
8be0709f | 737 | int in_ns; /* is this clock in nanoseconds? */ |
5079f326 | 738 | } trace_clocks[] = { |
8be0709f DS |
739 | { trace_clock_local, "local", 1 }, |
740 | { trace_clock_global, "global", 1 }, | |
741 | { trace_clock_counter, "counter", 0 }, | |
8aacf017 | 742 | { trace_clock_jiffies, "uptime", 1 }, |
76f11917 | 743 | { trace_clock, "perf", 1 }, |
8cbd9cc6 | 744 | ARCH_TRACE_CLOCKS |
5079f326 Z |
745 | }; |
746 | ||
747 | int trace_clock_id; | |
748 | ||
b63f39ea | 749 | /* |
750 | * trace_parser_get_init - gets the buffer for trace parser | |
751 | */ | |
752 | int trace_parser_get_init(struct trace_parser *parser, int size) | |
753 | { | |
754 | memset(parser, 0, sizeof(*parser)); | |
755 | ||
756 | parser->buffer = kmalloc(size, GFP_KERNEL); | |
757 | if (!parser->buffer) | |
758 | return 1; | |
759 | ||
760 | parser->size = size; | |
761 | return 0; | |
762 | } | |
763 | ||
764 | /* | |
765 | * trace_parser_put - frees the buffer for trace parser | |
766 | */ | |
767 | void trace_parser_put(struct trace_parser *parser) | |
768 | { | |
769 | kfree(parser->buffer); | |
770 | } | |
771 | ||
772 | /* | |
773 | * trace_get_user - reads the user input string separated by space | |
774 | * (matched by isspace(ch)) | |
775 | * | |
776 | * For each string found the 'struct trace_parser' is updated, | |
777 | * and the function returns. | |
778 | * | |
779 | * Returns number of bytes read. | |
780 | * | |
781 | * See kernel/trace/trace.h for 'struct trace_parser' details. | |
782 | */ | |
783 | int trace_get_user(struct trace_parser *parser, const char __user *ubuf, | |
784 | size_t cnt, loff_t *ppos) | |
785 | { | |
786 | char ch; | |
787 | size_t read = 0; | |
788 | ssize_t ret; | |
789 | ||
790 | if (!*ppos) | |
791 | trace_parser_clear(parser); | |
792 | ||
793 | ret = get_user(ch, ubuf++); | |
794 | if (ret) | |
795 | goto out; | |
796 | ||
797 | read++; | |
798 | cnt--; | |
799 | ||
800 | /* | |
801 | * The parser is not finished with the last write, | |
802 | * continue reading the user input without skipping spaces. | |
803 | */ | |
804 | if (!parser->cont) { | |
805 | /* skip white space */ | |
806 | while (cnt && isspace(ch)) { | |
807 | ret = get_user(ch, ubuf++); | |
808 | if (ret) | |
809 | goto out; | |
810 | read++; | |
811 | cnt--; | |
812 | } | |
813 | ||
814 | /* only spaces were written */ | |
815 | if (isspace(ch)) { | |
816 | *ppos += read; | |
817 | ret = read; | |
818 | goto out; | |
819 | } | |
820 | ||
821 | parser->idx = 0; | |
822 | } | |
823 | ||
824 | /* read the non-space input */ | |
825 | while (cnt && !isspace(ch)) { | |
3c235a33 | 826 | if (parser->idx < parser->size - 1) |
b63f39ea | 827 | parser->buffer[parser->idx++] = ch; |
828 | else { | |
829 | ret = -EINVAL; | |
830 | goto out; | |
831 | } | |
832 | ret = get_user(ch, ubuf++); | |
833 | if (ret) | |
834 | goto out; | |
835 | read++; | |
836 | cnt--; | |
837 | } | |
838 | ||
839 | /* We either got finished input or we have to wait for another call. */ | |
840 | if (isspace(ch)) { | |
841 | parser->buffer[parser->idx] = 0; | |
842 | parser->cont = false; | |
843 | } else { | |
844 | parser->cont = true; | |
845 | parser->buffer[parser->idx++] = ch; | |
846 | } | |
847 | ||
848 | *ppos += read; | |
849 | ret = read; | |
850 | ||
851 | out: | |
852 | return ret; | |
853 | } | |
854 | ||
6c6c2796 PP |
855 | ssize_t trace_seq_to_user(struct trace_seq *s, char __user *ubuf, size_t cnt) |
856 | { | |
857 | int len; | |
858 | int ret; | |
859 | ||
2dc5d12b SR |
860 | if (!cnt) |
861 | return 0; | |
862 | ||
6c6c2796 PP |
863 | if (s->len <= s->readpos) |
864 | return -EBUSY; | |
865 | ||
866 | len = s->len - s->readpos; | |
867 | if (cnt > len) | |
868 | cnt = len; | |
869 | ret = copy_to_user(ubuf, s->buffer + s->readpos, cnt); | |
2dc5d12b | 870 | if (ret == cnt) |
6c6c2796 PP |
871 | return -EFAULT; |
872 | ||
2dc5d12b SR |
873 | cnt -= ret; |
874 | ||
e74da523 | 875 | s->readpos += cnt; |
6c6c2796 | 876 | return cnt; |
214023c3 SR |
877 | } |
878 | ||
b8b94265 | 879 | static ssize_t trace_seq_to_buffer(struct trace_seq *s, void *buf, size_t cnt) |
3c56819b EGM |
880 | { |
881 | int len; | |
3c56819b EGM |
882 | |
883 | if (s->len <= s->readpos) | |
884 | return -EBUSY; | |
885 | ||
886 | len = s->len - s->readpos; | |
887 | if (cnt > len) | |
888 | cnt = len; | |
5a26c8f0 | 889 | memcpy(buf, s->buffer + s->readpos, cnt); |
3c56819b | 890 | |
e74da523 | 891 | s->readpos += cnt; |
3c56819b EGM |
892 | return cnt; |
893 | } | |
894 | ||
5d4a9dba SR |
895 | /* |
896 | * ftrace_max_lock is used to protect the swapping of buffers | |
897 | * when taking a max snapshot. The buffers themselves are | |
898 | * protected by per_cpu spinlocks. But the action of the swap | |
899 | * needs its own lock. | |
900 | * | |
445c8951 | 901 | * This is defined as a arch_spinlock_t in order to help |
5d4a9dba SR |
902 | * with performance when lockdep debugging is enabled. |
903 | * | |
904 | * It is also used in other places outside the update_max_tr | |
905 | * so it needs to be defined outside of the | |
906 | * CONFIG_TRACER_MAX_TRACE. | |
907 | */ | |
445c8951 | 908 | static arch_spinlock_t ftrace_max_lock = |
edc35bd7 | 909 | (arch_spinlock_t)__ARCH_SPIN_LOCK_UNLOCKED; |
5d4a9dba | 910 | |
0e950173 TB |
911 | unsigned long __read_mostly tracing_thresh; |
912 | ||
5d4a9dba SR |
913 | #ifdef CONFIG_TRACER_MAX_TRACE |
914 | unsigned long __read_mostly tracing_max_latency; | |
5d4a9dba SR |
915 | |
916 | /* | |
917 | * Copy the new maximum trace into the separate maximum-trace | |
918 | * structure. (this way the maximum trace is permanently saved, | |
919 | * for later retrieval via /sys/kernel/debug/tracing/latency_trace) | |
920 | */ | |
921 | static void | |
922 | __update_max_tr(struct trace_array *tr, struct task_struct *tsk, int cpu) | |
923 | { | |
12883efb SRRH |
924 | struct trace_buffer *trace_buf = &tr->trace_buffer; |
925 | struct trace_buffer *max_buf = &tr->max_buffer; | |
926 | struct trace_array_cpu *data = per_cpu_ptr(trace_buf->data, cpu); | |
927 | struct trace_array_cpu *max_data = per_cpu_ptr(max_buf->data, cpu); | |
5d4a9dba | 928 | |
12883efb SRRH |
929 | max_buf->cpu = cpu; |
930 | max_buf->time_start = data->preempt_timestamp; | |
5d4a9dba | 931 | |
8248ac05 SR |
932 | max_data->saved_latency = tracing_max_latency; |
933 | max_data->critical_start = data->critical_start; | |
934 | max_data->critical_end = data->critical_end; | |
5d4a9dba | 935 | |
1acaa1b2 | 936 | memcpy(max_data->comm, tsk->comm, TASK_COMM_LEN); |
8248ac05 | 937 | max_data->pid = tsk->pid; |
f17a5194 SRRH |
938 | /* |
939 | * If tsk == current, then use current_uid(), as that does not use | |
940 | * RCU. The irq tracer can be called out of RCU scope. | |
941 | */ | |
942 | if (tsk == current) | |
943 | max_data->uid = current_uid(); | |
944 | else | |
945 | max_data->uid = task_uid(tsk); | |
946 | ||
8248ac05 SR |
947 | max_data->nice = tsk->static_prio - 20 - MAX_RT_PRIO; |
948 | max_data->policy = tsk->policy; | |
949 | max_data->rt_priority = tsk->rt_priority; | |
5d4a9dba SR |
950 | |
951 | /* record this tasks comm */ | |
952 | tracing_record_cmdline(tsk); | |
953 | } | |
954 | ||
4fcdae83 SR |
955 | /** |
956 | * update_max_tr - snapshot all trace buffers from global_trace to max_tr | |
957 | * @tr: tracer | |
958 | * @tsk: the task with the latency | |
959 | * @cpu: The cpu that initiated the trace. | |
960 | * | |
961 | * Flip the buffers between the @tr and the max_tr and record information | |
962 | * about which task was the cause of this latency. | |
963 | */ | |
e309b41d | 964 | void |
bc0c38d1 SR |
965 | update_max_tr(struct trace_array *tr, struct task_struct *tsk, int cpu) |
966 | { | |
2721e72d | 967 | struct ring_buffer *buf; |
bc0c38d1 | 968 | |
2b6080f2 | 969 | if (tr->stop_count) |
b8de7bd1 SR |
970 | return; |
971 | ||
4c11d7ae | 972 | WARN_ON_ONCE(!irqs_disabled()); |
34600f0e | 973 | |
45ad21ca | 974 | if (!tr->allocated_snapshot) { |
debdd57f | 975 | /* Only the nop tracer should hit this when disabling */ |
2b6080f2 | 976 | WARN_ON_ONCE(tr->current_trace != &nop_trace); |
34600f0e | 977 | return; |
debdd57f | 978 | } |
34600f0e | 979 | |
0199c4e6 | 980 | arch_spin_lock(&ftrace_max_lock); |
3928a8a2 | 981 | |
12883efb SRRH |
982 | buf = tr->trace_buffer.buffer; |
983 | tr->trace_buffer.buffer = tr->max_buffer.buffer; | |
984 | tr->max_buffer.buffer = buf; | |
3928a8a2 | 985 | |
bc0c38d1 | 986 | __update_max_tr(tr, tsk, cpu); |
0199c4e6 | 987 | arch_spin_unlock(&ftrace_max_lock); |
bc0c38d1 SR |
988 | } |
989 | ||
990 | /** | |
991 | * update_max_tr_single - only copy one trace over, and reset the rest | |
992 | * @tr - tracer | |
993 | * @tsk - task with the latency | |
994 | * @cpu - the cpu of the buffer to copy. | |
4fcdae83 SR |
995 | * |
996 | * Flip the trace of a single CPU buffer between the @tr and the max_tr. | |
bc0c38d1 | 997 | */ |
e309b41d | 998 | void |
bc0c38d1 SR |
999 | update_max_tr_single(struct trace_array *tr, struct task_struct *tsk, int cpu) |
1000 | { | |
3928a8a2 | 1001 | int ret; |
bc0c38d1 | 1002 | |
2b6080f2 | 1003 | if (tr->stop_count) |
b8de7bd1 SR |
1004 | return; |
1005 | ||
4c11d7ae | 1006 | WARN_ON_ONCE(!irqs_disabled()); |
6c24499f | 1007 | if (!tr->allocated_snapshot) { |
2930e04d | 1008 | /* Only the nop tracer should hit this when disabling */ |
9e8529af | 1009 | WARN_ON_ONCE(tr->current_trace != &nop_trace); |
ef710e10 | 1010 | return; |
2930e04d | 1011 | } |
ef710e10 | 1012 | |
0199c4e6 | 1013 | arch_spin_lock(&ftrace_max_lock); |
bc0c38d1 | 1014 | |
12883efb | 1015 | ret = ring_buffer_swap_cpu(tr->max_buffer.buffer, tr->trace_buffer.buffer, cpu); |
3928a8a2 | 1016 | |
e8165dbb SR |
1017 | if (ret == -EBUSY) { |
1018 | /* | |
1019 | * We failed to swap the buffer due to a commit taking | |
1020 | * place on this CPU. We fail to record, but we reset | |
1021 | * the max trace buffer (no one writes directly to it) | |
1022 | * and flag that it failed. | |
1023 | */ | |
12883efb | 1024 | trace_array_printk_buf(tr->max_buffer.buffer, _THIS_IP_, |
e8165dbb SR |
1025 | "Failed to swap buffers due to commit in progress\n"); |
1026 | } | |
1027 | ||
e8165dbb | 1028 | WARN_ON_ONCE(ret && ret != -EAGAIN && ret != -EBUSY); |
bc0c38d1 SR |
1029 | |
1030 | __update_max_tr(tr, tsk, cpu); | |
0199c4e6 | 1031 | arch_spin_unlock(&ftrace_max_lock); |
bc0c38d1 | 1032 | } |
5d4a9dba | 1033 | #endif /* CONFIG_TRACER_MAX_TRACE */ |
bc0c38d1 | 1034 | |
0d5c6e1c SR |
1035 | static void default_wait_pipe(struct trace_iterator *iter) |
1036 | { | |
15693458 SRRH |
1037 | /* Iterators are static, they should be filled or empty */ |
1038 | if (trace_buffer_iter(iter, iter->cpu_file)) | |
1039 | return; | |
0d5c6e1c | 1040 | |
12883efb | 1041 | ring_buffer_wait(iter->trace_buffer->buffer, iter->cpu_file); |
0d5c6e1c SR |
1042 | } |
1043 | ||
f4e781c0 SRRH |
1044 | #ifdef CONFIG_FTRACE_STARTUP_TEST |
1045 | static int run_tracer_selftest(struct tracer *type) | |
1046 | { | |
1047 | struct trace_array *tr = &global_trace; | |
1048 | struct tracer *saved_tracer = tr->current_trace; | |
1049 | int ret; | |
0d5c6e1c | 1050 | |
f4e781c0 SRRH |
1051 | if (!type->selftest || tracing_selftest_disabled) |
1052 | return 0; | |
0d5c6e1c SR |
1053 | |
1054 | /* | |
f4e781c0 SRRH |
1055 | * Run a selftest on this tracer. |
1056 | * Here we reset the trace buffer, and set the current | |
1057 | * tracer to be this tracer. The tracer can then run some | |
1058 | * internal tracing to verify that everything is in order. | |
1059 | * If we fail, we do not register this tracer. | |
0d5c6e1c | 1060 | */ |
f4e781c0 | 1061 | tracing_reset_online_cpus(&tr->trace_buffer); |
0d5c6e1c | 1062 | |
f4e781c0 SRRH |
1063 | tr->current_trace = type; |
1064 | ||
1065 | #ifdef CONFIG_TRACER_MAX_TRACE | |
1066 | if (type->use_max_tr) { | |
1067 | /* If we expanded the buffers, make sure the max is expanded too */ | |
1068 | if (ring_buffer_expanded) | |
1069 | ring_buffer_resize(tr->max_buffer.buffer, trace_buf_size, | |
1070 | RING_BUFFER_ALL_CPUS); | |
1071 | tr->allocated_snapshot = true; | |
1072 | } | |
1073 | #endif | |
1074 | ||
1075 | /* the test is responsible for initializing and enabling */ | |
1076 | pr_info("Testing tracer %s: ", type->name); | |
1077 | ret = type->selftest(type, tr); | |
1078 | /* the test is responsible for resetting too */ | |
1079 | tr->current_trace = saved_tracer; | |
1080 | if (ret) { | |
1081 | printk(KERN_CONT "FAILED!\n"); | |
1082 | /* Add the warning after printing 'FAILED' */ | |
1083 | WARN_ON(1); | |
1084 | return -1; | |
1085 | } | |
1086 | /* Only reset on passing, to avoid touching corrupted buffers */ | |
1087 | tracing_reset_online_cpus(&tr->trace_buffer); | |
1088 | ||
1089 | #ifdef CONFIG_TRACER_MAX_TRACE | |
1090 | if (type->use_max_tr) { | |
1091 | tr->allocated_snapshot = false; | |
0d5c6e1c | 1092 | |
f4e781c0 SRRH |
1093 | /* Shrink the max buffer again */ |
1094 | if (ring_buffer_expanded) | |
1095 | ring_buffer_resize(tr->max_buffer.buffer, 1, | |
1096 | RING_BUFFER_ALL_CPUS); | |
1097 | } | |
1098 | #endif | |
1099 | ||
1100 | printk(KERN_CONT "PASSED\n"); | |
1101 | return 0; | |
1102 | } | |
1103 | #else | |
1104 | static inline int run_tracer_selftest(struct tracer *type) | |
1105 | { | |
1106 | return 0; | |
0d5c6e1c | 1107 | } |
f4e781c0 | 1108 | #endif /* CONFIG_FTRACE_STARTUP_TEST */ |
0d5c6e1c | 1109 | |
4fcdae83 SR |
1110 | /** |
1111 | * register_tracer - register a tracer with the ftrace system. | |
1112 | * @type - the plugin for the tracer | |
1113 | * | |
1114 | * Register a new plugin tracer. | |
1115 | */ | |
bc0c38d1 SR |
1116 | int register_tracer(struct tracer *type) |
1117 | { | |
1118 | struct tracer *t; | |
bc0c38d1 SR |
1119 | int ret = 0; |
1120 | ||
1121 | if (!type->name) { | |
1122 | pr_info("Tracer must have a name\n"); | |
1123 | return -1; | |
1124 | } | |
1125 | ||
24a461d5 | 1126 | if (strlen(type->name) >= MAX_TRACER_SIZE) { |
ee6c2c1b LZ |
1127 | pr_info("Tracer has a name longer than %d\n", MAX_TRACER_SIZE); |
1128 | return -1; | |
1129 | } | |
1130 | ||
bc0c38d1 | 1131 | mutex_lock(&trace_types_lock); |
86fa2f60 | 1132 | |
8e1b82e0 FW |
1133 | tracing_selftest_running = true; |
1134 | ||
bc0c38d1 SR |
1135 | for (t = trace_types; t; t = t->next) { |
1136 | if (strcmp(type->name, t->name) == 0) { | |
1137 | /* already found */ | |
ee6c2c1b | 1138 | pr_info("Tracer %s already registered\n", |
bc0c38d1 SR |
1139 | type->name); |
1140 | ret = -1; | |
1141 | goto out; | |
1142 | } | |
1143 | } | |
1144 | ||
adf9f195 FW |
1145 | if (!type->set_flag) |
1146 | type->set_flag = &dummy_set_flag; | |
1147 | if (!type->flags) | |
1148 | type->flags = &dummy_tracer_flags; | |
1149 | else | |
1150 | if (!type->flags->opts) | |
1151 | type->flags->opts = dummy_tracer_opt; | |
6eaaa5d5 FW |
1152 | if (!type->wait_pipe) |
1153 | type->wait_pipe = default_wait_pipe; | |
1154 | ||
f4e781c0 SRRH |
1155 | ret = run_tracer_selftest(type); |
1156 | if (ret < 0) | |
1157 | goto out; | |
60a11774 | 1158 | |
bc0c38d1 SR |
1159 | type->next = trace_types; |
1160 | trace_types = type; | |
60a11774 | 1161 | |
bc0c38d1 | 1162 | out: |
8e1b82e0 | 1163 | tracing_selftest_running = false; |
bc0c38d1 SR |
1164 | mutex_unlock(&trace_types_lock); |
1165 | ||
dac74940 SR |
1166 | if (ret || !default_bootup_tracer) |
1167 | goto out_unlock; | |
1168 | ||
ee6c2c1b | 1169 | if (strncmp(default_bootup_tracer, type->name, MAX_TRACER_SIZE)) |
dac74940 SR |
1170 | goto out_unlock; |
1171 | ||
1172 | printk(KERN_INFO "Starting tracer '%s'\n", type->name); | |
1173 | /* Do we want this tracer to start on bootup? */ | |
1174 | tracing_set_tracer(type->name); | |
1175 | default_bootup_tracer = NULL; | |
1176 | /* disable other selftests, since this will break it. */ | |
55034cd6 | 1177 | tracing_selftest_disabled = true; |
b2821ae6 | 1178 | #ifdef CONFIG_FTRACE_STARTUP_TEST |
dac74940 SR |
1179 | printk(KERN_INFO "Disabling FTRACE selftests due to running tracer '%s'\n", |
1180 | type->name); | |
b2821ae6 | 1181 | #endif |
b2821ae6 | 1182 | |
dac74940 | 1183 | out_unlock: |
bc0c38d1 SR |
1184 | return ret; |
1185 | } | |
1186 | ||
12883efb | 1187 | void tracing_reset(struct trace_buffer *buf, int cpu) |
f633903a | 1188 | { |
12883efb | 1189 | struct ring_buffer *buffer = buf->buffer; |
f633903a | 1190 | |
a5416411 HT |
1191 | if (!buffer) |
1192 | return; | |
1193 | ||
f633903a SR |
1194 | ring_buffer_record_disable(buffer); |
1195 | ||
1196 | /* Make sure all commits have finished */ | |
1197 | synchronize_sched(); | |
68179686 | 1198 | ring_buffer_reset_cpu(buffer, cpu); |
f633903a SR |
1199 | |
1200 | ring_buffer_record_enable(buffer); | |
1201 | } | |
1202 | ||
12883efb | 1203 | void tracing_reset_online_cpus(struct trace_buffer *buf) |
213cc060 | 1204 | { |
12883efb | 1205 | struct ring_buffer *buffer = buf->buffer; |
213cc060 PE |
1206 | int cpu; |
1207 | ||
a5416411 HT |
1208 | if (!buffer) |
1209 | return; | |
1210 | ||
621968cd SR |
1211 | ring_buffer_record_disable(buffer); |
1212 | ||
1213 | /* Make sure all commits have finished */ | |
1214 | synchronize_sched(); | |
1215 | ||
12883efb | 1216 | buf->time_start = ftrace_now(buf->cpu); |
213cc060 PE |
1217 | |
1218 | for_each_online_cpu(cpu) | |
68179686 | 1219 | ring_buffer_reset_cpu(buffer, cpu); |
621968cd SR |
1220 | |
1221 | ring_buffer_record_enable(buffer); | |
213cc060 PE |
1222 | } |
1223 | ||
9456f0fa SR |
1224 | void tracing_reset_current(int cpu) |
1225 | { | |
12883efb | 1226 | tracing_reset(&global_trace.trace_buffer, cpu); |
9456f0fa SR |
1227 | } |
1228 | ||
873c642f | 1229 | void tracing_reset_all_online_cpus(void) |
9456f0fa | 1230 | { |
873c642f SRRH |
1231 | struct trace_array *tr; |
1232 | ||
1233 | mutex_lock(&trace_types_lock); | |
1234 | list_for_each_entry(tr, &ftrace_trace_arrays, list) { | |
12883efb SRRH |
1235 | tracing_reset_online_cpus(&tr->trace_buffer); |
1236 | #ifdef CONFIG_TRACER_MAX_TRACE | |
1237 | tracing_reset_online_cpus(&tr->max_buffer); | |
1238 | #endif | |
873c642f SRRH |
1239 | } |
1240 | mutex_unlock(&trace_types_lock); | |
9456f0fa SR |
1241 | } |
1242 | ||
bc0c38d1 | 1243 | #define SAVED_CMDLINES 128 |
2c7eea4c | 1244 | #define NO_CMDLINE_MAP UINT_MAX |
bc0c38d1 SR |
1245 | static unsigned map_pid_to_cmdline[PID_MAX_DEFAULT+1]; |
1246 | static unsigned map_cmdline_to_pid[SAVED_CMDLINES]; | |
1247 | static char saved_cmdlines[SAVED_CMDLINES][TASK_COMM_LEN]; | |
1248 | static int cmdline_idx; | |
edc35bd7 | 1249 | static arch_spinlock_t trace_cmdline_lock = __ARCH_SPIN_LOCK_UNLOCKED; |
25b0b44a | 1250 | |
25b0b44a | 1251 | /* temporary disable recording */ |
4fd27358 | 1252 | static atomic_t trace_record_cmdline_disabled __read_mostly; |
bc0c38d1 SR |
1253 | |
1254 | static void trace_init_cmdlines(void) | |
1255 | { | |
2c7eea4c TG |
1256 | memset(&map_pid_to_cmdline, NO_CMDLINE_MAP, sizeof(map_pid_to_cmdline)); |
1257 | memset(&map_cmdline_to_pid, NO_CMDLINE_MAP, sizeof(map_cmdline_to_pid)); | |
bc0c38d1 SR |
1258 | cmdline_idx = 0; |
1259 | } | |
1260 | ||
b5130b1e CE |
1261 | int is_tracing_stopped(void) |
1262 | { | |
2b6080f2 | 1263 | return global_trace.stop_count; |
b5130b1e CE |
1264 | } |
1265 | ||
69bb54ec SR |
1266 | /** |
1267 | * ftrace_off_permanent - disable all ftrace code permanently | |
1268 | * | |
1269 | * This should only be called when a serious anomally has | |
1270 | * been detected. This will turn off the function tracing, | |
1271 | * ring buffers, and other tracing utilites. It takes no | |
1272 | * locks and can be called from any context. | |
1273 | */ | |
1274 | void ftrace_off_permanent(void) | |
1275 | { | |
1276 | tracing_disabled = 1; | |
1277 | ftrace_stop(); | |
1278 | tracing_off_permanent(); | |
1279 | } | |
1280 | ||
0f048701 SR |
1281 | /** |
1282 | * tracing_start - quick start of the tracer | |
1283 | * | |
1284 | * If tracing is enabled but was stopped by tracing_stop, | |
1285 | * this will start the tracer back up. | |
1286 | */ | |
1287 | void tracing_start(void) | |
1288 | { | |
1289 | struct ring_buffer *buffer; | |
1290 | unsigned long flags; | |
1291 | ||
1292 | if (tracing_disabled) | |
1293 | return; | |
1294 | ||
2b6080f2 SR |
1295 | raw_spin_lock_irqsave(&global_trace.start_lock, flags); |
1296 | if (--global_trace.stop_count) { | |
1297 | if (global_trace.stop_count < 0) { | |
b06a8301 SR |
1298 | /* Someone screwed up their debugging */ |
1299 | WARN_ON_ONCE(1); | |
2b6080f2 | 1300 | global_trace.stop_count = 0; |
b06a8301 | 1301 | } |
0f048701 SR |
1302 | goto out; |
1303 | } | |
1304 | ||
a2f80714 SR |
1305 | /* Prevent the buffers from switching */ |
1306 | arch_spin_lock(&ftrace_max_lock); | |
0f048701 | 1307 | |
12883efb | 1308 | buffer = global_trace.trace_buffer.buffer; |
0f048701 SR |
1309 | if (buffer) |
1310 | ring_buffer_record_enable(buffer); | |
1311 | ||
12883efb SRRH |
1312 | #ifdef CONFIG_TRACER_MAX_TRACE |
1313 | buffer = global_trace.max_buffer.buffer; | |
0f048701 SR |
1314 | if (buffer) |
1315 | ring_buffer_record_enable(buffer); | |
12883efb | 1316 | #endif |
0f048701 | 1317 | |
a2f80714 SR |
1318 | arch_spin_unlock(&ftrace_max_lock); |
1319 | ||
0f048701 SR |
1320 | ftrace_start(); |
1321 | out: | |
2b6080f2 SR |
1322 | raw_spin_unlock_irqrestore(&global_trace.start_lock, flags); |
1323 | } | |
1324 | ||
1325 | static void tracing_start_tr(struct trace_array *tr) | |
1326 | { | |
1327 | struct ring_buffer *buffer; | |
1328 | unsigned long flags; | |
1329 | ||
1330 | if (tracing_disabled) | |
1331 | return; | |
1332 | ||
1333 | /* If global, we need to also start the max tracer */ | |
1334 | if (tr->flags & TRACE_ARRAY_FL_GLOBAL) | |
1335 | return tracing_start(); | |
1336 | ||
1337 | raw_spin_lock_irqsave(&tr->start_lock, flags); | |
1338 | ||
1339 | if (--tr->stop_count) { | |
1340 | if (tr->stop_count < 0) { | |
1341 | /* Someone screwed up their debugging */ | |
1342 | WARN_ON_ONCE(1); | |
1343 | tr->stop_count = 0; | |
1344 | } | |
1345 | goto out; | |
1346 | } | |
1347 | ||
12883efb | 1348 | buffer = tr->trace_buffer.buffer; |
2b6080f2 SR |
1349 | if (buffer) |
1350 | ring_buffer_record_enable(buffer); | |
1351 | ||
1352 | out: | |
1353 | raw_spin_unlock_irqrestore(&tr->start_lock, flags); | |
0f048701 SR |
1354 | } |
1355 | ||
1356 | /** | |
1357 | * tracing_stop - quick stop of the tracer | |
1358 | * | |
1359 | * Light weight way to stop tracing. Use in conjunction with | |
1360 | * tracing_start. | |
1361 | */ | |
1362 | void tracing_stop(void) | |
1363 | { | |
1364 | struct ring_buffer *buffer; | |
1365 | unsigned long flags; | |
1366 | ||
1367 | ftrace_stop(); | |
2b6080f2 SR |
1368 | raw_spin_lock_irqsave(&global_trace.start_lock, flags); |
1369 | if (global_trace.stop_count++) | |
0f048701 SR |
1370 | goto out; |
1371 | ||
a2f80714 SR |
1372 | /* Prevent the buffers from switching */ |
1373 | arch_spin_lock(&ftrace_max_lock); | |
1374 | ||
12883efb | 1375 | buffer = global_trace.trace_buffer.buffer; |
0f048701 SR |
1376 | if (buffer) |
1377 | ring_buffer_record_disable(buffer); | |
1378 | ||
12883efb SRRH |
1379 | #ifdef CONFIG_TRACER_MAX_TRACE |
1380 | buffer = global_trace.max_buffer.buffer; | |
0f048701 SR |
1381 | if (buffer) |
1382 | ring_buffer_record_disable(buffer); | |
12883efb | 1383 | #endif |
0f048701 | 1384 | |
a2f80714 SR |
1385 | arch_spin_unlock(&ftrace_max_lock); |
1386 | ||
0f048701 | 1387 | out: |
2b6080f2 SR |
1388 | raw_spin_unlock_irqrestore(&global_trace.start_lock, flags); |
1389 | } | |
1390 | ||
1391 | static void tracing_stop_tr(struct trace_array *tr) | |
1392 | { | |
1393 | struct ring_buffer *buffer; | |
1394 | unsigned long flags; | |
1395 | ||
1396 | /* If global, we need to also stop the max tracer */ | |
1397 | if (tr->flags & TRACE_ARRAY_FL_GLOBAL) | |
1398 | return tracing_stop(); | |
1399 | ||
1400 | raw_spin_lock_irqsave(&tr->start_lock, flags); | |
1401 | if (tr->stop_count++) | |
1402 | goto out; | |
1403 | ||
12883efb | 1404 | buffer = tr->trace_buffer.buffer; |
2b6080f2 SR |
1405 | if (buffer) |
1406 | ring_buffer_record_disable(buffer); | |
1407 | ||
1408 | out: | |
1409 | raw_spin_unlock_irqrestore(&tr->start_lock, flags); | |
0f048701 SR |
1410 | } |
1411 | ||
e309b41d | 1412 | void trace_stop_cmdline_recording(void); |
bc0c38d1 | 1413 | |
e309b41d | 1414 | static void trace_save_cmdline(struct task_struct *tsk) |
bc0c38d1 | 1415 | { |
a635cf04 | 1416 | unsigned pid, idx; |
bc0c38d1 SR |
1417 | |
1418 | if (!tsk->pid || unlikely(tsk->pid > PID_MAX_DEFAULT)) | |
1419 | return; | |
1420 | ||
1421 | /* | |
1422 | * It's not the end of the world if we don't get | |
1423 | * the lock, but we also don't want to spin | |
1424 | * nor do we want to disable interrupts, | |
1425 | * so if we miss here, then better luck next time. | |
1426 | */ | |
0199c4e6 | 1427 | if (!arch_spin_trylock(&trace_cmdline_lock)) |
bc0c38d1 SR |
1428 | return; |
1429 | ||
1430 | idx = map_pid_to_cmdline[tsk->pid]; | |
2c7eea4c | 1431 | if (idx == NO_CMDLINE_MAP) { |
bc0c38d1 SR |
1432 | idx = (cmdline_idx + 1) % SAVED_CMDLINES; |
1433 | ||
a635cf04 CE |
1434 | /* |
1435 | * Check whether the cmdline buffer at idx has a pid | |
1436 | * mapped. We are going to overwrite that entry so we | |
1437 | * need to clear the map_pid_to_cmdline. Otherwise we | |
1438 | * would read the new comm for the old pid. | |
1439 | */ | |
1440 | pid = map_cmdline_to_pid[idx]; | |
1441 | if (pid != NO_CMDLINE_MAP) | |
1442 | map_pid_to_cmdline[pid] = NO_CMDLINE_MAP; | |
bc0c38d1 | 1443 | |
a635cf04 | 1444 | map_cmdline_to_pid[idx] = tsk->pid; |
bc0c38d1 SR |
1445 | map_pid_to_cmdline[tsk->pid] = idx; |
1446 | ||
1447 | cmdline_idx = idx; | |
1448 | } | |
1449 | ||
1450 | memcpy(&saved_cmdlines[idx], tsk->comm, TASK_COMM_LEN); | |
1451 | ||
0199c4e6 | 1452 | arch_spin_unlock(&trace_cmdline_lock); |
bc0c38d1 SR |
1453 | } |
1454 | ||
4ca53085 | 1455 | void trace_find_cmdline(int pid, char comm[]) |
bc0c38d1 | 1456 | { |
bc0c38d1 SR |
1457 | unsigned map; |
1458 | ||
4ca53085 SR |
1459 | if (!pid) { |
1460 | strcpy(comm, "<idle>"); | |
1461 | return; | |
1462 | } | |
bc0c38d1 | 1463 | |
74bf4076 SR |
1464 | if (WARN_ON_ONCE(pid < 0)) { |
1465 | strcpy(comm, "<XXX>"); | |
1466 | return; | |
1467 | } | |
1468 | ||
4ca53085 SR |
1469 | if (pid > PID_MAX_DEFAULT) { |
1470 | strcpy(comm, "<...>"); | |
1471 | return; | |
1472 | } | |
bc0c38d1 | 1473 | |
5b6045a9 | 1474 | preempt_disable(); |
0199c4e6 | 1475 | arch_spin_lock(&trace_cmdline_lock); |
bc0c38d1 | 1476 | map = map_pid_to_cmdline[pid]; |
50d88758 TG |
1477 | if (map != NO_CMDLINE_MAP) |
1478 | strcpy(comm, saved_cmdlines[map]); | |
1479 | else | |
1480 | strcpy(comm, "<...>"); | |
bc0c38d1 | 1481 | |
0199c4e6 | 1482 | arch_spin_unlock(&trace_cmdline_lock); |
5b6045a9 | 1483 | preempt_enable(); |
bc0c38d1 SR |
1484 | } |
1485 | ||
e309b41d | 1486 | void tracing_record_cmdline(struct task_struct *tsk) |
bc0c38d1 | 1487 | { |
0fb9656d | 1488 | if (atomic_read(&trace_record_cmdline_disabled) || !tracing_is_on()) |
bc0c38d1 SR |
1489 | return; |
1490 | ||
7ffbd48d SR |
1491 | if (!__this_cpu_read(trace_cmdline_save)) |
1492 | return; | |
1493 | ||
1494 | __this_cpu_write(trace_cmdline_save, false); | |
1495 | ||
bc0c38d1 SR |
1496 | trace_save_cmdline(tsk); |
1497 | } | |
1498 | ||
45dcd8b8 | 1499 | void |
38697053 SR |
1500 | tracing_generic_entry_update(struct trace_entry *entry, unsigned long flags, |
1501 | int pc) | |
bc0c38d1 SR |
1502 | { |
1503 | struct task_struct *tsk = current; | |
bc0c38d1 | 1504 | |
777e208d SR |
1505 | entry->preempt_count = pc & 0xff; |
1506 | entry->pid = (tsk) ? tsk->pid : 0; | |
1507 | entry->flags = | |
9244489a | 1508 | #ifdef CONFIG_TRACE_IRQFLAGS_SUPPORT |
2e2ca155 | 1509 | (irqs_disabled_flags(flags) ? TRACE_FLAG_IRQS_OFF : 0) | |
9244489a SR |
1510 | #else |
1511 | TRACE_FLAG_IRQS_NOSUPPORT | | |
1512 | #endif | |
bc0c38d1 SR |
1513 | ((pc & HARDIRQ_MASK) ? TRACE_FLAG_HARDIRQ : 0) | |
1514 | ((pc & SOFTIRQ_MASK) ? TRACE_FLAG_SOFTIRQ : 0) | | |
1515 | (need_resched() ? TRACE_FLAG_NEED_RESCHED : 0); | |
1516 | } | |
f413cdb8 | 1517 | EXPORT_SYMBOL_GPL(tracing_generic_entry_update); |
bc0c38d1 | 1518 | |
e77405ad SR |
1519 | struct ring_buffer_event * |
1520 | trace_buffer_lock_reserve(struct ring_buffer *buffer, | |
1521 | int type, | |
1522 | unsigned long len, | |
1523 | unsigned long flags, int pc) | |
51a763dd ACM |
1524 | { |
1525 | struct ring_buffer_event *event; | |
1526 | ||
e77405ad | 1527 | event = ring_buffer_lock_reserve(buffer, len); |
51a763dd ACM |
1528 | if (event != NULL) { |
1529 | struct trace_entry *ent = ring_buffer_event_data(event); | |
1530 | ||
1531 | tracing_generic_entry_update(ent, flags, pc); | |
1532 | ent->type = type; | |
1533 | } | |
1534 | ||
1535 | return event; | |
1536 | } | |
51a763dd | 1537 | |
7ffbd48d SR |
1538 | void |
1539 | __buffer_unlock_commit(struct ring_buffer *buffer, struct ring_buffer_event *event) | |
1540 | { | |
1541 | __this_cpu_write(trace_cmdline_save, true); | |
1542 | ring_buffer_unlock_commit(buffer, event); | |
1543 | } | |
1544 | ||
e77405ad SR |
1545 | static inline void |
1546 | __trace_buffer_unlock_commit(struct ring_buffer *buffer, | |
1547 | struct ring_buffer_event *event, | |
0d5c6e1c | 1548 | unsigned long flags, int pc) |
51a763dd | 1549 | { |
7ffbd48d | 1550 | __buffer_unlock_commit(buffer, event); |
51a763dd | 1551 | |
e77405ad SR |
1552 | ftrace_trace_stack(buffer, flags, 6, pc); |
1553 | ftrace_trace_userstack(buffer, flags, pc); | |
07edf712 FW |
1554 | } |
1555 | ||
e77405ad SR |
1556 | void trace_buffer_unlock_commit(struct ring_buffer *buffer, |
1557 | struct ring_buffer_event *event, | |
1558 | unsigned long flags, int pc) | |
07edf712 | 1559 | { |
0d5c6e1c | 1560 | __trace_buffer_unlock_commit(buffer, event, flags, pc); |
51a763dd | 1561 | } |
0d5c6e1c | 1562 | EXPORT_SYMBOL_GPL(trace_buffer_unlock_commit); |
51a763dd | 1563 | |
ccb469a1 SR |
1564 | struct ring_buffer_event * |
1565 | trace_event_buffer_lock_reserve(struct ring_buffer **current_rb, | |
1566 | struct ftrace_event_file *ftrace_file, | |
1567 | int type, unsigned long len, | |
1568 | unsigned long flags, int pc) | |
1569 | { | |
12883efb | 1570 | *current_rb = ftrace_file->tr->trace_buffer.buffer; |
ccb469a1 SR |
1571 | return trace_buffer_lock_reserve(*current_rb, |
1572 | type, len, flags, pc); | |
1573 | } | |
1574 | EXPORT_SYMBOL_GPL(trace_event_buffer_lock_reserve); | |
1575 | ||
ef5580d0 | 1576 | struct ring_buffer_event * |
e77405ad SR |
1577 | trace_current_buffer_lock_reserve(struct ring_buffer **current_rb, |
1578 | int type, unsigned long len, | |
ef5580d0 SR |
1579 | unsigned long flags, int pc) |
1580 | { | |
12883efb | 1581 | *current_rb = global_trace.trace_buffer.buffer; |
e77405ad | 1582 | return trace_buffer_lock_reserve(*current_rb, |
ef5580d0 SR |
1583 | type, len, flags, pc); |
1584 | } | |
94487d6d | 1585 | EXPORT_SYMBOL_GPL(trace_current_buffer_lock_reserve); |
ef5580d0 | 1586 | |
e77405ad SR |
1587 | void trace_current_buffer_unlock_commit(struct ring_buffer *buffer, |
1588 | struct ring_buffer_event *event, | |
ef5580d0 SR |
1589 | unsigned long flags, int pc) |
1590 | { | |
0d5c6e1c | 1591 | __trace_buffer_unlock_commit(buffer, event, flags, pc); |
07edf712 | 1592 | } |
94487d6d | 1593 | EXPORT_SYMBOL_GPL(trace_current_buffer_unlock_commit); |
07edf712 | 1594 | |
0d5c6e1c SR |
1595 | void trace_buffer_unlock_commit_regs(struct ring_buffer *buffer, |
1596 | struct ring_buffer_event *event, | |
1597 | unsigned long flags, int pc, | |
1598 | struct pt_regs *regs) | |
1fd8df2c | 1599 | { |
7ffbd48d | 1600 | __buffer_unlock_commit(buffer, event); |
1fd8df2c MH |
1601 | |
1602 | ftrace_trace_stack_regs(buffer, flags, 0, pc, regs); | |
1603 | ftrace_trace_userstack(buffer, flags, pc); | |
1604 | } | |
0d5c6e1c | 1605 | EXPORT_SYMBOL_GPL(trace_buffer_unlock_commit_regs); |
1fd8df2c | 1606 | |
e77405ad SR |
1607 | void trace_current_buffer_discard_commit(struct ring_buffer *buffer, |
1608 | struct ring_buffer_event *event) | |
77d9f465 | 1609 | { |
e77405ad | 1610 | ring_buffer_discard_commit(buffer, event); |
ef5580d0 | 1611 | } |
12acd473 | 1612 | EXPORT_SYMBOL_GPL(trace_current_buffer_discard_commit); |
ef5580d0 | 1613 | |
e309b41d | 1614 | void |
7be42151 | 1615 | trace_function(struct trace_array *tr, |
38697053 SR |
1616 | unsigned long ip, unsigned long parent_ip, unsigned long flags, |
1617 | int pc) | |
bc0c38d1 | 1618 | { |
e1112b4d | 1619 | struct ftrace_event_call *call = &event_function; |
12883efb | 1620 | struct ring_buffer *buffer = tr->trace_buffer.buffer; |
3928a8a2 | 1621 | struct ring_buffer_event *event; |
777e208d | 1622 | struct ftrace_entry *entry; |
bc0c38d1 | 1623 | |
d769041f | 1624 | /* If we are reading the ring buffer, don't trace */ |
dd17c8f7 | 1625 | if (unlikely(__this_cpu_read(ftrace_cpu_disabled))) |
d769041f SR |
1626 | return; |
1627 | ||
e77405ad | 1628 | event = trace_buffer_lock_reserve(buffer, TRACE_FN, sizeof(*entry), |
51a763dd | 1629 | flags, pc); |
3928a8a2 SR |
1630 | if (!event) |
1631 | return; | |
1632 | entry = ring_buffer_event_data(event); | |
777e208d SR |
1633 | entry->ip = ip; |
1634 | entry->parent_ip = parent_ip; | |
e1112b4d | 1635 | |
e77405ad | 1636 | if (!filter_check_discard(call, entry, buffer, event)) |
7ffbd48d | 1637 | __buffer_unlock_commit(buffer, event); |
bc0c38d1 SR |
1638 | } |
1639 | ||
e309b41d | 1640 | void |
2e0f5761 | 1641 | ftrace(struct trace_array *tr, struct trace_array_cpu *data, |
38697053 SR |
1642 | unsigned long ip, unsigned long parent_ip, unsigned long flags, |
1643 | int pc) | |
2e0f5761 IM |
1644 | { |
1645 | if (likely(!atomic_read(&data->disabled))) | |
7be42151 | 1646 | trace_function(tr, ip, parent_ip, flags, pc); |
2e0f5761 IM |
1647 | } |
1648 | ||
c0a0d0d3 | 1649 | #ifdef CONFIG_STACKTRACE |
4a9bd3f1 SR |
1650 | |
1651 | #define FTRACE_STACK_MAX_ENTRIES (PAGE_SIZE / sizeof(unsigned long)) | |
1652 | struct ftrace_stack { | |
1653 | unsigned long calls[FTRACE_STACK_MAX_ENTRIES]; | |
1654 | }; | |
1655 | ||
1656 | static DEFINE_PER_CPU(struct ftrace_stack, ftrace_stack); | |
1657 | static DEFINE_PER_CPU(int, ftrace_stack_reserve); | |
1658 | ||
e77405ad | 1659 | static void __ftrace_trace_stack(struct ring_buffer *buffer, |
53614991 | 1660 | unsigned long flags, |
1fd8df2c | 1661 | int skip, int pc, struct pt_regs *regs) |
86387f7e | 1662 | { |
e1112b4d | 1663 | struct ftrace_event_call *call = &event_kernel_stack; |
3928a8a2 | 1664 | struct ring_buffer_event *event; |
777e208d | 1665 | struct stack_entry *entry; |
86387f7e | 1666 | struct stack_trace trace; |
4a9bd3f1 SR |
1667 | int use_stack; |
1668 | int size = FTRACE_STACK_ENTRIES; | |
1669 | ||
1670 | trace.nr_entries = 0; | |
1671 | trace.skip = skip; | |
1672 | ||
1673 | /* | |
1674 | * Since events can happen in NMIs there's no safe way to | |
1675 | * use the per cpu ftrace_stacks. We reserve it and if an interrupt | |
1676 | * or NMI comes in, it will just have to use the default | |
1677 | * FTRACE_STACK_SIZE. | |
1678 | */ | |
1679 | preempt_disable_notrace(); | |
1680 | ||
82146529 | 1681 | use_stack = __this_cpu_inc_return(ftrace_stack_reserve); |
4a9bd3f1 SR |
1682 | /* |
1683 | * We don't need any atomic variables, just a barrier. | |
1684 | * If an interrupt comes in, we don't care, because it would | |
1685 | * have exited and put the counter back to what we want. | |
1686 | * We just need a barrier to keep gcc from moving things | |
1687 | * around. | |
1688 | */ | |
1689 | barrier(); | |
1690 | if (use_stack == 1) { | |
1691 | trace.entries = &__get_cpu_var(ftrace_stack).calls[0]; | |
1692 | trace.max_entries = FTRACE_STACK_MAX_ENTRIES; | |
1693 | ||
1694 | if (regs) | |
1695 | save_stack_trace_regs(regs, &trace); | |
1696 | else | |
1697 | save_stack_trace(&trace); | |
1698 | ||
1699 | if (trace.nr_entries > size) | |
1700 | size = trace.nr_entries; | |
1701 | } else | |
1702 | /* From now on, use_stack is a boolean */ | |
1703 | use_stack = 0; | |
1704 | ||
1705 | size *= sizeof(unsigned long); | |
86387f7e | 1706 | |
e77405ad | 1707 | event = trace_buffer_lock_reserve(buffer, TRACE_STACK, |
4a9bd3f1 | 1708 | sizeof(*entry) + size, flags, pc); |
3928a8a2 | 1709 | if (!event) |
4a9bd3f1 SR |
1710 | goto out; |
1711 | entry = ring_buffer_event_data(event); | |
86387f7e | 1712 | |
4a9bd3f1 SR |
1713 | memset(&entry->caller, 0, size); |
1714 | ||
1715 | if (use_stack) | |
1716 | memcpy(&entry->caller, trace.entries, | |
1717 | trace.nr_entries * sizeof(unsigned long)); | |
1718 | else { | |
1719 | trace.max_entries = FTRACE_STACK_ENTRIES; | |
1720 | trace.entries = entry->caller; | |
1721 | if (regs) | |
1722 | save_stack_trace_regs(regs, &trace); | |
1723 | else | |
1724 | save_stack_trace(&trace); | |
1725 | } | |
1726 | ||
1727 | entry->size = trace.nr_entries; | |
86387f7e | 1728 | |
e77405ad | 1729 | if (!filter_check_discard(call, entry, buffer, event)) |
7ffbd48d | 1730 | __buffer_unlock_commit(buffer, event); |
4a9bd3f1 SR |
1731 | |
1732 | out: | |
1733 | /* Again, don't let gcc optimize things here */ | |
1734 | barrier(); | |
82146529 | 1735 | __this_cpu_dec(ftrace_stack_reserve); |
4a9bd3f1 SR |
1736 | preempt_enable_notrace(); |
1737 | ||
f0a920d5 IM |
1738 | } |
1739 | ||
1fd8df2c MH |
1740 | void ftrace_trace_stack_regs(struct ring_buffer *buffer, unsigned long flags, |
1741 | int skip, int pc, struct pt_regs *regs) | |
1742 | { | |
1743 | if (!(trace_flags & TRACE_ITER_STACKTRACE)) | |
1744 | return; | |
1745 | ||
1746 | __ftrace_trace_stack(buffer, flags, skip, pc, regs); | |
1747 | } | |
1748 | ||
e77405ad SR |
1749 | void ftrace_trace_stack(struct ring_buffer *buffer, unsigned long flags, |
1750 | int skip, int pc) | |
53614991 SR |
1751 | { |
1752 | if (!(trace_flags & TRACE_ITER_STACKTRACE)) | |
1753 | return; | |
1754 | ||
1fd8df2c | 1755 | __ftrace_trace_stack(buffer, flags, skip, pc, NULL); |
53614991 SR |
1756 | } |
1757 | ||
c0a0d0d3 FW |
1758 | void __trace_stack(struct trace_array *tr, unsigned long flags, int skip, |
1759 | int pc) | |
38697053 | 1760 | { |
12883efb | 1761 | __ftrace_trace_stack(tr->trace_buffer.buffer, flags, skip, pc, NULL); |
38697053 SR |
1762 | } |
1763 | ||
03889384 SR |
1764 | /** |
1765 | * trace_dump_stack - record a stack back trace in the trace buffer | |
c142be8e | 1766 | * @skip: Number of functions to skip (helper handlers) |
03889384 | 1767 | */ |
c142be8e | 1768 | void trace_dump_stack(int skip) |
03889384 SR |
1769 | { |
1770 | unsigned long flags; | |
1771 | ||
1772 | if (tracing_disabled || tracing_selftest_running) | |
e36c5458 | 1773 | return; |
03889384 SR |
1774 | |
1775 | local_save_flags(flags); | |
1776 | ||
c142be8e SRRH |
1777 | /* |
1778 | * Skip 3 more, seems to get us at the caller of | |
1779 | * this function. | |
1780 | */ | |
1781 | skip += 3; | |
1782 | __ftrace_trace_stack(global_trace.trace_buffer.buffer, | |
1783 | flags, skip, preempt_count(), NULL); | |
03889384 SR |
1784 | } |
1785 | ||
91e86e56 SR |
1786 | static DEFINE_PER_CPU(int, user_stack_count); |
1787 | ||
e77405ad SR |
1788 | void |
1789 | ftrace_trace_userstack(struct ring_buffer *buffer, unsigned long flags, int pc) | |
02b67518 | 1790 | { |
e1112b4d | 1791 | struct ftrace_event_call *call = &event_user_stack; |
8d7c6a96 | 1792 | struct ring_buffer_event *event; |
02b67518 TE |
1793 | struct userstack_entry *entry; |
1794 | struct stack_trace trace; | |
02b67518 TE |
1795 | |
1796 | if (!(trace_flags & TRACE_ITER_USERSTACKTRACE)) | |
1797 | return; | |
1798 | ||
b6345879 SR |
1799 | /* |
1800 | * NMIs can not handle page faults, even with fix ups. | |
1801 | * The save user stack can (and often does) fault. | |
1802 | */ | |
1803 | if (unlikely(in_nmi())) | |
1804 | return; | |
02b67518 | 1805 | |
91e86e56 SR |
1806 | /* |
1807 | * prevent recursion, since the user stack tracing may | |
1808 | * trigger other kernel events. | |
1809 | */ | |
1810 | preempt_disable(); | |
1811 | if (__this_cpu_read(user_stack_count)) | |
1812 | goto out; | |
1813 | ||
1814 | __this_cpu_inc(user_stack_count); | |
1815 | ||
e77405ad | 1816 | event = trace_buffer_lock_reserve(buffer, TRACE_USER_STACK, |
51a763dd | 1817 | sizeof(*entry), flags, pc); |
02b67518 | 1818 | if (!event) |
1dbd1951 | 1819 | goto out_drop_count; |
02b67518 | 1820 | entry = ring_buffer_event_data(event); |
02b67518 | 1821 | |
48659d31 | 1822 | entry->tgid = current->tgid; |
02b67518 TE |
1823 | memset(&entry->caller, 0, sizeof(entry->caller)); |
1824 | ||
1825 | trace.nr_entries = 0; | |
1826 | trace.max_entries = FTRACE_STACK_ENTRIES; | |
1827 | trace.skip = 0; | |
1828 | trace.entries = entry->caller; | |
1829 | ||
1830 | save_stack_trace_user(&trace); | |
e77405ad | 1831 | if (!filter_check_discard(call, entry, buffer, event)) |
7ffbd48d | 1832 | __buffer_unlock_commit(buffer, event); |
91e86e56 | 1833 | |
1dbd1951 | 1834 | out_drop_count: |
91e86e56 | 1835 | __this_cpu_dec(user_stack_count); |
91e86e56 SR |
1836 | out: |
1837 | preempt_enable(); | |
02b67518 TE |
1838 | } |
1839 | ||
4fd27358 HE |
1840 | #ifdef UNUSED |
1841 | static void __trace_userstack(struct trace_array *tr, unsigned long flags) | |
02b67518 | 1842 | { |
7be42151 | 1843 | ftrace_trace_userstack(tr, flags, preempt_count()); |
02b67518 | 1844 | } |
4fd27358 | 1845 | #endif /* UNUSED */ |
02b67518 | 1846 | |
c0a0d0d3 FW |
1847 | #endif /* CONFIG_STACKTRACE */ |
1848 | ||
07d777fe SR |
1849 | /* created for use with alloc_percpu */ |
1850 | struct trace_buffer_struct { | |
1851 | char buffer[TRACE_BUF_SIZE]; | |
1852 | }; | |
1853 | ||
1854 | static struct trace_buffer_struct *trace_percpu_buffer; | |
1855 | static struct trace_buffer_struct *trace_percpu_sirq_buffer; | |
1856 | static struct trace_buffer_struct *trace_percpu_irq_buffer; | |
1857 | static struct trace_buffer_struct *trace_percpu_nmi_buffer; | |
1858 | ||
1859 | /* | |
1860 | * The buffer used is dependent on the context. There is a per cpu | |
1861 | * buffer for normal context, softirq contex, hard irq context and | |
1862 | * for NMI context. Thise allows for lockless recording. | |
1863 | * | |
1864 | * Note, if the buffers failed to be allocated, then this returns NULL | |
1865 | */ | |
1866 | static char *get_trace_buf(void) | |
1867 | { | |
1868 | struct trace_buffer_struct *percpu_buffer; | |
07d777fe SR |
1869 | |
1870 | /* | |
1871 | * If we have allocated per cpu buffers, then we do not | |
1872 | * need to do any locking. | |
1873 | */ | |
1874 | if (in_nmi()) | |
1875 | percpu_buffer = trace_percpu_nmi_buffer; | |
1876 | else if (in_irq()) | |
1877 | percpu_buffer = trace_percpu_irq_buffer; | |
1878 | else if (in_softirq()) | |
1879 | percpu_buffer = trace_percpu_sirq_buffer; | |
1880 | else | |
1881 | percpu_buffer = trace_percpu_buffer; | |
1882 | ||
1883 | if (!percpu_buffer) | |
1884 | return NULL; | |
1885 | ||
d8a0349c | 1886 | return this_cpu_ptr(&percpu_buffer->buffer[0]); |
07d777fe SR |
1887 | } |
1888 | ||
1889 | static int alloc_percpu_trace_buffer(void) | |
1890 | { | |
1891 | struct trace_buffer_struct *buffers; | |
1892 | struct trace_buffer_struct *sirq_buffers; | |
1893 | struct trace_buffer_struct *irq_buffers; | |
1894 | struct trace_buffer_struct *nmi_buffers; | |
1895 | ||
1896 | buffers = alloc_percpu(struct trace_buffer_struct); | |
1897 | if (!buffers) | |
1898 | goto err_warn; | |
1899 | ||
1900 | sirq_buffers = alloc_percpu(struct trace_buffer_struct); | |
1901 | if (!sirq_buffers) | |
1902 | goto err_sirq; | |
1903 | ||
1904 | irq_buffers = alloc_percpu(struct trace_buffer_struct); | |
1905 | if (!irq_buffers) | |
1906 | goto err_irq; | |
1907 | ||
1908 | nmi_buffers = alloc_percpu(struct trace_buffer_struct); | |
1909 | if (!nmi_buffers) | |
1910 | goto err_nmi; | |
1911 | ||
1912 | trace_percpu_buffer = buffers; | |
1913 | trace_percpu_sirq_buffer = sirq_buffers; | |
1914 | trace_percpu_irq_buffer = irq_buffers; | |
1915 | trace_percpu_nmi_buffer = nmi_buffers; | |
1916 | ||
1917 | return 0; | |
1918 | ||
1919 | err_nmi: | |
1920 | free_percpu(irq_buffers); | |
1921 | err_irq: | |
1922 | free_percpu(sirq_buffers); | |
1923 | err_sirq: | |
1924 | free_percpu(buffers); | |
1925 | err_warn: | |
1926 | WARN(1, "Could not allocate percpu trace_printk buffer"); | |
1927 | return -ENOMEM; | |
1928 | } | |
1929 | ||
81698831 SR |
1930 | static int buffers_allocated; |
1931 | ||
07d777fe SR |
1932 | void trace_printk_init_buffers(void) |
1933 | { | |
07d777fe SR |
1934 | if (buffers_allocated) |
1935 | return; | |
1936 | ||
1937 | if (alloc_percpu_trace_buffer()) | |
1938 | return; | |
1939 | ||
1940 | pr_info("ftrace: Allocated trace_printk buffers\n"); | |
1941 | ||
b382ede6 SR |
1942 | /* Expand the buffers to set size */ |
1943 | tracing_update_buffers(); | |
1944 | ||
07d777fe | 1945 | buffers_allocated = 1; |
81698831 SR |
1946 | |
1947 | /* | |
1948 | * trace_printk_init_buffers() can be called by modules. | |
1949 | * If that happens, then we need to start cmdline recording | |
1950 | * directly here. If the global_trace.buffer is already | |
1951 | * allocated here, then this was called by module code. | |
1952 | */ | |
12883efb | 1953 | if (global_trace.trace_buffer.buffer) |
81698831 SR |
1954 | tracing_start_cmdline_record(); |
1955 | } | |
1956 | ||
1957 | void trace_printk_start_comm(void) | |
1958 | { | |
1959 | /* Start tracing comms if trace printk is set */ | |
1960 | if (!buffers_allocated) | |
1961 | return; | |
1962 | tracing_start_cmdline_record(); | |
1963 | } | |
1964 | ||
1965 | static void trace_printk_start_stop_comm(int enabled) | |
1966 | { | |
1967 | if (!buffers_allocated) | |
1968 | return; | |
1969 | ||
1970 | if (enabled) | |
1971 | tracing_start_cmdline_record(); | |
1972 | else | |
1973 | tracing_stop_cmdline_record(); | |
07d777fe SR |
1974 | } |
1975 | ||
769b0441 | 1976 | /** |
48ead020 | 1977 | * trace_vbprintk - write binary msg to tracing buffer |
769b0441 FW |
1978 | * |
1979 | */ | |
40ce74f1 | 1980 | int trace_vbprintk(unsigned long ip, const char *fmt, va_list args) |
769b0441 | 1981 | { |
e1112b4d | 1982 | struct ftrace_event_call *call = &event_bprint; |
769b0441 | 1983 | struct ring_buffer_event *event; |
e77405ad | 1984 | struct ring_buffer *buffer; |
769b0441 | 1985 | struct trace_array *tr = &global_trace; |
48ead020 | 1986 | struct bprint_entry *entry; |
769b0441 | 1987 | unsigned long flags; |
07d777fe SR |
1988 | char *tbuffer; |
1989 | int len = 0, size, pc; | |
769b0441 FW |
1990 | |
1991 | if (unlikely(tracing_selftest_running || tracing_disabled)) | |
1992 | return 0; | |
1993 | ||
1994 | /* Don't pollute graph traces with trace_vprintk internals */ | |
1995 | pause_graph_tracing(); | |
1996 | ||
1997 | pc = preempt_count(); | |
5168ae50 | 1998 | preempt_disable_notrace(); |
769b0441 | 1999 | |
07d777fe SR |
2000 | tbuffer = get_trace_buf(); |
2001 | if (!tbuffer) { | |
2002 | len = 0; | |
769b0441 | 2003 | goto out; |
07d777fe | 2004 | } |
769b0441 | 2005 | |
07d777fe | 2006 | len = vbin_printf((u32 *)tbuffer, TRACE_BUF_SIZE/sizeof(int), fmt, args); |
769b0441 | 2007 | |
07d777fe SR |
2008 | if (len > TRACE_BUF_SIZE/sizeof(int) || len < 0) |
2009 | goto out; | |
769b0441 | 2010 | |
07d777fe | 2011 | local_save_flags(flags); |
769b0441 | 2012 | size = sizeof(*entry) + sizeof(u32) * len; |
12883efb | 2013 | buffer = tr->trace_buffer.buffer; |
e77405ad SR |
2014 | event = trace_buffer_lock_reserve(buffer, TRACE_BPRINT, size, |
2015 | flags, pc); | |
769b0441 | 2016 | if (!event) |
07d777fe | 2017 | goto out; |
769b0441 FW |
2018 | entry = ring_buffer_event_data(event); |
2019 | entry->ip = ip; | |
769b0441 FW |
2020 | entry->fmt = fmt; |
2021 | ||
07d777fe | 2022 | memcpy(entry->buf, tbuffer, sizeof(u32) * len); |
d931369b | 2023 | if (!filter_check_discard(call, entry, buffer, event)) { |
7ffbd48d | 2024 | __buffer_unlock_commit(buffer, event); |
d931369b SR |
2025 | ftrace_trace_stack(buffer, flags, 6, pc); |
2026 | } | |
769b0441 | 2027 | |
769b0441 | 2028 | out: |
5168ae50 | 2029 | preempt_enable_notrace(); |
769b0441 FW |
2030 | unpause_graph_tracing(); |
2031 | ||
2032 | return len; | |
2033 | } | |
48ead020 FW |
2034 | EXPORT_SYMBOL_GPL(trace_vbprintk); |
2035 | ||
12883efb SRRH |
2036 | static int |
2037 | __trace_array_vprintk(struct ring_buffer *buffer, | |
2038 | unsigned long ip, const char *fmt, va_list args) | |
48ead020 | 2039 | { |
e1112b4d | 2040 | struct ftrace_event_call *call = &event_print; |
48ead020 | 2041 | struct ring_buffer_event *event; |
07d777fe | 2042 | int len = 0, size, pc; |
48ead020 | 2043 | struct print_entry *entry; |
07d777fe SR |
2044 | unsigned long flags; |
2045 | char *tbuffer; | |
48ead020 FW |
2046 | |
2047 | if (tracing_disabled || tracing_selftest_running) | |
2048 | return 0; | |
2049 | ||
07d777fe SR |
2050 | /* Don't pollute graph traces with trace_vprintk internals */ |
2051 | pause_graph_tracing(); | |
2052 | ||
48ead020 FW |
2053 | pc = preempt_count(); |
2054 | preempt_disable_notrace(); | |
48ead020 | 2055 | |
07d777fe SR |
2056 | |
2057 | tbuffer = get_trace_buf(); | |
2058 | if (!tbuffer) { | |
2059 | len = 0; | |
48ead020 | 2060 | goto out; |
07d777fe | 2061 | } |
48ead020 | 2062 | |
07d777fe SR |
2063 | len = vsnprintf(tbuffer, TRACE_BUF_SIZE, fmt, args); |
2064 | if (len > TRACE_BUF_SIZE) | |
2065 | goto out; | |
48ead020 | 2066 | |
07d777fe | 2067 | local_save_flags(flags); |
48ead020 | 2068 | size = sizeof(*entry) + len + 1; |
e77405ad | 2069 | event = trace_buffer_lock_reserve(buffer, TRACE_PRINT, size, |
07d777fe | 2070 | flags, pc); |
48ead020 | 2071 | if (!event) |
07d777fe | 2072 | goto out; |
48ead020 | 2073 | entry = ring_buffer_event_data(event); |
c13d2f7c | 2074 | entry->ip = ip; |
48ead020 | 2075 | |
07d777fe | 2076 | memcpy(&entry->buf, tbuffer, len); |
c13d2f7c | 2077 | entry->buf[len] = '\0'; |
d931369b | 2078 | if (!filter_check_discard(call, entry, buffer, event)) { |
7ffbd48d | 2079 | __buffer_unlock_commit(buffer, event); |
07d777fe | 2080 | ftrace_trace_stack(buffer, flags, 6, pc); |
d931369b | 2081 | } |
48ead020 FW |
2082 | out: |
2083 | preempt_enable_notrace(); | |
07d777fe | 2084 | unpause_graph_tracing(); |
48ead020 FW |
2085 | |
2086 | return len; | |
2087 | } | |
659372d3 | 2088 | |
12883efb SRRH |
2089 | int trace_array_vprintk(struct trace_array *tr, |
2090 | unsigned long ip, const char *fmt, va_list args) | |
2091 | { | |
2092 | return __trace_array_vprintk(tr->trace_buffer.buffer, ip, fmt, args); | |
2093 | } | |
2094 | ||
2095 | int trace_array_printk(struct trace_array *tr, | |
2096 | unsigned long ip, const char *fmt, ...) | |
2097 | { | |
2098 | int ret; | |
2099 | va_list ap; | |
2100 | ||
2101 | if (!(trace_flags & TRACE_ITER_PRINTK)) | |
2102 | return 0; | |
2103 | ||
2104 | va_start(ap, fmt); | |
2105 | ret = trace_array_vprintk(tr, ip, fmt, ap); | |
2106 | va_end(ap); | |
2107 | return ret; | |
2108 | } | |
2109 | ||
2110 | int trace_array_printk_buf(struct ring_buffer *buffer, | |
2111 | unsigned long ip, const char *fmt, ...) | |
2112 | { | |
2113 | int ret; | |
2114 | va_list ap; | |
2115 | ||
2116 | if (!(trace_flags & TRACE_ITER_PRINTK)) | |
2117 | return 0; | |
2118 | ||
2119 | va_start(ap, fmt); | |
2120 | ret = __trace_array_vprintk(buffer, ip, fmt, ap); | |
2121 | va_end(ap); | |
2122 | return ret; | |
2123 | } | |
2124 | ||
659372d3 SR |
2125 | int trace_vprintk(unsigned long ip, const char *fmt, va_list args) |
2126 | { | |
a813a159 | 2127 | return trace_array_vprintk(&global_trace, ip, fmt, args); |
659372d3 | 2128 | } |
769b0441 FW |
2129 | EXPORT_SYMBOL_GPL(trace_vprintk); |
2130 | ||
e2ac8ef5 | 2131 | static void trace_iterator_increment(struct trace_iterator *iter) |
5a90f577 | 2132 | { |
6d158a81 SR |
2133 | struct ring_buffer_iter *buf_iter = trace_buffer_iter(iter, iter->cpu); |
2134 | ||
5a90f577 | 2135 | iter->idx++; |
6d158a81 SR |
2136 | if (buf_iter) |
2137 | ring_buffer_read(buf_iter, NULL); | |
5a90f577 SR |
2138 | } |
2139 | ||
e309b41d | 2140 | static struct trace_entry * |
bc21b478 SR |
2141 | peek_next_entry(struct trace_iterator *iter, int cpu, u64 *ts, |
2142 | unsigned long *lost_events) | |
dd0e545f | 2143 | { |
3928a8a2 | 2144 | struct ring_buffer_event *event; |
6d158a81 | 2145 | struct ring_buffer_iter *buf_iter = trace_buffer_iter(iter, cpu); |
dd0e545f | 2146 | |
d769041f SR |
2147 | if (buf_iter) |
2148 | event = ring_buffer_iter_peek(buf_iter, ts); | |
2149 | else | |
12883efb | 2150 | event = ring_buffer_peek(iter->trace_buffer->buffer, cpu, ts, |
bc21b478 | 2151 | lost_events); |
d769041f | 2152 | |
4a9bd3f1 SR |
2153 | if (event) { |
2154 | iter->ent_size = ring_buffer_event_length(event); | |
2155 | return ring_buffer_event_data(event); | |
2156 | } | |
2157 | iter->ent_size = 0; | |
2158 | return NULL; | |
dd0e545f | 2159 | } |
d769041f | 2160 | |
dd0e545f | 2161 | static struct trace_entry * |
bc21b478 SR |
2162 | __find_next_entry(struct trace_iterator *iter, int *ent_cpu, |
2163 | unsigned long *missing_events, u64 *ent_ts) | |
bc0c38d1 | 2164 | { |
12883efb | 2165 | struct ring_buffer *buffer = iter->trace_buffer->buffer; |
bc0c38d1 | 2166 | struct trace_entry *ent, *next = NULL; |
aa27497c | 2167 | unsigned long lost_events = 0, next_lost = 0; |
b04cc6b1 | 2168 | int cpu_file = iter->cpu_file; |
3928a8a2 | 2169 | u64 next_ts = 0, ts; |
bc0c38d1 | 2170 | int next_cpu = -1; |
12b5da34 | 2171 | int next_size = 0; |
bc0c38d1 SR |
2172 | int cpu; |
2173 | ||
b04cc6b1 FW |
2174 | /* |
2175 | * If we are in a per_cpu trace file, don't bother by iterating over | |
2176 | * all cpu and peek directly. | |
2177 | */ | |
ae3b5093 | 2178 | if (cpu_file > RING_BUFFER_ALL_CPUS) { |
b04cc6b1 FW |
2179 | if (ring_buffer_empty_cpu(buffer, cpu_file)) |
2180 | return NULL; | |
bc21b478 | 2181 | ent = peek_next_entry(iter, cpu_file, ent_ts, missing_events); |
b04cc6b1 FW |
2182 | if (ent_cpu) |
2183 | *ent_cpu = cpu_file; | |
2184 | ||
2185 | return ent; | |
2186 | } | |
2187 | ||
ab46428c | 2188 | for_each_tracing_cpu(cpu) { |
dd0e545f | 2189 | |
3928a8a2 SR |
2190 | if (ring_buffer_empty_cpu(buffer, cpu)) |
2191 | continue; | |
dd0e545f | 2192 | |
bc21b478 | 2193 | ent = peek_next_entry(iter, cpu, &ts, &lost_events); |
dd0e545f | 2194 | |
cdd31cd2 IM |
2195 | /* |
2196 | * Pick the entry with the smallest timestamp: | |
2197 | */ | |
3928a8a2 | 2198 | if (ent && (!next || ts < next_ts)) { |
bc0c38d1 SR |
2199 | next = ent; |
2200 | next_cpu = cpu; | |
3928a8a2 | 2201 | next_ts = ts; |
bc21b478 | 2202 | next_lost = lost_events; |
12b5da34 | 2203 | next_size = iter->ent_size; |
bc0c38d1 SR |
2204 | } |
2205 | } | |
2206 | ||
12b5da34 SR |
2207 | iter->ent_size = next_size; |
2208 | ||
bc0c38d1 SR |
2209 | if (ent_cpu) |
2210 | *ent_cpu = next_cpu; | |
2211 | ||
3928a8a2 SR |
2212 | if (ent_ts) |
2213 | *ent_ts = next_ts; | |
2214 | ||
bc21b478 SR |
2215 | if (missing_events) |
2216 | *missing_events = next_lost; | |
2217 | ||
bc0c38d1 SR |
2218 | return next; |
2219 | } | |
2220 | ||
dd0e545f | 2221 | /* Find the next real entry, without updating the iterator itself */ |
c4a8e8be FW |
2222 | struct trace_entry *trace_find_next_entry(struct trace_iterator *iter, |
2223 | int *ent_cpu, u64 *ent_ts) | |
bc0c38d1 | 2224 | { |
bc21b478 | 2225 | return __find_next_entry(iter, ent_cpu, NULL, ent_ts); |
dd0e545f SR |
2226 | } |
2227 | ||
2228 | /* Find the next real entry, and increment the iterator to the next entry */ | |
955b61e5 | 2229 | void *trace_find_next_entry_inc(struct trace_iterator *iter) |
dd0e545f | 2230 | { |
bc21b478 SR |
2231 | iter->ent = __find_next_entry(iter, &iter->cpu, |
2232 | &iter->lost_events, &iter->ts); | |
dd0e545f | 2233 | |
3928a8a2 | 2234 | if (iter->ent) |
e2ac8ef5 | 2235 | trace_iterator_increment(iter); |
dd0e545f | 2236 | |
3928a8a2 | 2237 | return iter->ent ? iter : NULL; |
b3806b43 | 2238 | } |
bc0c38d1 | 2239 | |
e309b41d | 2240 | static void trace_consume(struct trace_iterator *iter) |
b3806b43 | 2241 | { |
12883efb | 2242 | ring_buffer_consume(iter->trace_buffer->buffer, iter->cpu, &iter->ts, |
bc21b478 | 2243 | &iter->lost_events); |
bc0c38d1 SR |
2244 | } |
2245 | ||
e309b41d | 2246 | static void *s_next(struct seq_file *m, void *v, loff_t *pos) |
bc0c38d1 SR |
2247 | { |
2248 | struct trace_iterator *iter = m->private; | |
bc0c38d1 | 2249 | int i = (int)*pos; |
4e3c3333 | 2250 | void *ent; |
bc0c38d1 | 2251 | |
a63ce5b3 SR |
2252 | WARN_ON_ONCE(iter->leftover); |
2253 | ||
bc0c38d1 SR |
2254 | (*pos)++; |
2255 | ||
2256 | /* can't go backwards */ | |
2257 | if (iter->idx > i) | |
2258 | return NULL; | |
2259 | ||
2260 | if (iter->idx < 0) | |
955b61e5 | 2261 | ent = trace_find_next_entry_inc(iter); |
bc0c38d1 SR |
2262 | else |
2263 | ent = iter; | |
2264 | ||
2265 | while (ent && iter->idx < i) | |
955b61e5 | 2266 | ent = trace_find_next_entry_inc(iter); |
bc0c38d1 SR |
2267 | |
2268 | iter->pos = *pos; | |
2269 | ||
bc0c38d1 SR |
2270 | return ent; |
2271 | } | |
2272 | ||
955b61e5 | 2273 | void tracing_iter_reset(struct trace_iterator *iter, int cpu) |
2f26ebd5 | 2274 | { |
2f26ebd5 SR |
2275 | struct ring_buffer_event *event; |
2276 | struct ring_buffer_iter *buf_iter; | |
2277 | unsigned long entries = 0; | |
2278 | u64 ts; | |
2279 | ||
12883efb | 2280 | per_cpu_ptr(iter->trace_buffer->data, cpu)->skipped_entries = 0; |
2f26ebd5 | 2281 | |
6d158a81 SR |
2282 | buf_iter = trace_buffer_iter(iter, cpu); |
2283 | if (!buf_iter) | |
2f26ebd5 SR |
2284 | return; |
2285 | ||
2f26ebd5 SR |
2286 | ring_buffer_iter_reset(buf_iter); |
2287 | ||
2288 | /* | |
2289 | * We could have the case with the max latency tracers | |
2290 | * that a reset never took place on a cpu. This is evident | |
2291 | * by the timestamp being before the start of the buffer. | |
2292 | */ | |
2293 | while ((event = ring_buffer_iter_peek(buf_iter, &ts))) { | |
12883efb | 2294 | if (ts >= iter->trace_buffer->time_start) |
2f26ebd5 SR |
2295 | break; |
2296 | entries++; | |
2297 | ring_buffer_read(buf_iter, NULL); | |
2298 | } | |
2299 | ||
12883efb | 2300 | per_cpu_ptr(iter->trace_buffer->data, cpu)->skipped_entries = entries; |
2f26ebd5 SR |
2301 | } |
2302 | ||
d7350c3f | 2303 | /* |
d7350c3f FW |
2304 | * The current tracer is copied to avoid a global locking |
2305 | * all around. | |
2306 | */ | |
bc0c38d1 SR |
2307 | static void *s_start(struct seq_file *m, loff_t *pos) |
2308 | { | |
2309 | struct trace_iterator *iter = m->private; | |
2b6080f2 | 2310 | struct trace_array *tr = iter->tr; |
b04cc6b1 | 2311 | int cpu_file = iter->cpu_file; |
bc0c38d1 SR |
2312 | void *p = NULL; |
2313 | loff_t l = 0; | |
3928a8a2 | 2314 | int cpu; |
bc0c38d1 | 2315 | |
2fd196ec HT |
2316 | /* |
2317 | * copy the tracer to avoid using a global lock all around. | |
2318 | * iter->trace is a copy of current_trace, the pointer to the | |
2319 | * name may be used instead of a strcmp(), as iter->trace->name | |
2320 | * will point to the same string as current_trace->name. | |
2321 | */ | |
bc0c38d1 | 2322 | mutex_lock(&trace_types_lock); |
2b6080f2 SR |
2323 | if (unlikely(tr->current_trace && iter->trace->name != tr->current_trace->name)) |
2324 | *iter->trace = *tr->current_trace; | |
d7350c3f | 2325 | mutex_unlock(&trace_types_lock); |
bc0c38d1 | 2326 | |
12883efb | 2327 | #ifdef CONFIG_TRACER_MAX_TRACE |
debdd57f HT |
2328 | if (iter->snapshot && iter->trace->use_max_tr) |
2329 | return ERR_PTR(-EBUSY); | |
12883efb | 2330 | #endif |
debdd57f HT |
2331 | |
2332 | if (!iter->snapshot) | |
2333 | atomic_inc(&trace_record_cmdline_disabled); | |
bc0c38d1 | 2334 | |
bc0c38d1 SR |
2335 | if (*pos != iter->pos) { |
2336 | iter->ent = NULL; | |
2337 | iter->cpu = 0; | |
2338 | iter->idx = -1; | |
2339 | ||
ae3b5093 | 2340 | if (cpu_file == RING_BUFFER_ALL_CPUS) { |
b04cc6b1 | 2341 | for_each_tracing_cpu(cpu) |
2f26ebd5 | 2342 | tracing_iter_reset(iter, cpu); |
b04cc6b1 | 2343 | } else |
2f26ebd5 | 2344 | tracing_iter_reset(iter, cpu_file); |
bc0c38d1 | 2345 | |
ac91d854 | 2346 | iter->leftover = 0; |
bc0c38d1 SR |
2347 | for (p = iter; p && l < *pos; p = s_next(m, p, &l)) |
2348 | ; | |
2349 | ||
2350 | } else { | |
a63ce5b3 SR |
2351 | /* |
2352 | * If we overflowed the seq_file before, then we want | |
2353 | * to just reuse the trace_seq buffer again. | |
2354 | */ | |
2355 | if (iter->leftover) | |
2356 | p = iter; | |
2357 | else { | |
2358 | l = *pos - 1; | |
2359 | p = s_next(m, p, &l); | |
2360 | } | |
bc0c38d1 SR |
2361 | } |
2362 | ||
4f535968 | 2363 | trace_event_read_lock(); |
7e53bd42 | 2364 | trace_access_lock(cpu_file); |
bc0c38d1 SR |
2365 | return p; |
2366 | } | |
2367 | ||
2368 | static void s_stop(struct seq_file *m, void *p) | |
2369 | { | |
7e53bd42 LJ |
2370 | struct trace_iterator *iter = m->private; |
2371 | ||
12883efb | 2372 | #ifdef CONFIG_TRACER_MAX_TRACE |
debdd57f HT |
2373 | if (iter->snapshot && iter->trace->use_max_tr) |
2374 | return; | |
12883efb | 2375 | #endif |
debdd57f HT |
2376 | |
2377 | if (!iter->snapshot) | |
2378 | atomic_dec(&trace_record_cmdline_disabled); | |
12883efb | 2379 | |
7e53bd42 | 2380 | trace_access_unlock(iter->cpu_file); |
4f535968 | 2381 | trace_event_read_unlock(); |
bc0c38d1 SR |
2382 | } |
2383 | ||
39eaf7ef | 2384 | static void |
12883efb SRRH |
2385 | get_total_entries(struct trace_buffer *buf, |
2386 | unsigned long *total, unsigned long *entries) | |
39eaf7ef SR |
2387 | { |
2388 | unsigned long count; | |
2389 | int cpu; | |
2390 | ||
2391 | *total = 0; | |
2392 | *entries = 0; | |
2393 | ||
2394 | for_each_tracing_cpu(cpu) { | |
12883efb | 2395 | count = ring_buffer_entries_cpu(buf->buffer, cpu); |
39eaf7ef SR |
2396 | /* |
2397 | * If this buffer has skipped entries, then we hold all | |
2398 | * entries for the trace and we need to ignore the | |
2399 | * ones before the time stamp. | |
2400 | */ | |
12883efb SRRH |
2401 | if (per_cpu_ptr(buf->data, cpu)->skipped_entries) { |
2402 | count -= per_cpu_ptr(buf->data, cpu)->skipped_entries; | |
39eaf7ef SR |
2403 | /* total is the same as the entries */ |
2404 | *total += count; | |
2405 | } else | |
2406 | *total += count + | |
12883efb | 2407 | ring_buffer_overrun_cpu(buf->buffer, cpu); |
39eaf7ef SR |
2408 | *entries += count; |
2409 | } | |
2410 | } | |
2411 | ||
e309b41d | 2412 | static void print_lat_help_header(struct seq_file *m) |
bc0c38d1 | 2413 | { |
a6168353 ME |
2414 | seq_puts(m, "# _------=> CPU# \n"); |
2415 | seq_puts(m, "# / _-----=> irqs-off \n"); | |
2416 | seq_puts(m, "# | / _----=> need-resched \n"); | |
2417 | seq_puts(m, "# || / _---=> hardirq/softirq \n"); | |
2418 | seq_puts(m, "# ||| / _--=> preempt-depth \n"); | |
e6e1e259 SR |
2419 | seq_puts(m, "# |||| / delay \n"); |
2420 | seq_puts(m, "# cmd pid ||||| time | caller \n"); | |
2421 | seq_puts(m, "# \\ / ||||| \\ | / \n"); | |
bc0c38d1 SR |
2422 | } |
2423 | ||
12883efb | 2424 | static void print_event_info(struct trace_buffer *buf, struct seq_file *m) |
bc0c38d1 | 2425 | { |
39eaf7ef SR |
2426 | unsigned long total; |
2427 | unsigned long entries; | |
2428 | ||
12883efb | 2429 | get_total_entries(buf, &total, &entries); |
39eaf7ef SR |
2430 | seq_printf(m, "# entries-in-buffer/entries-written: %lu/%lu #P:%d\n", |
2431 | entries, total, num_online_cpus()); | |
2432 | seq_puts(m, "#\n"); | |
2433 | } | |
2434 | ||
12883efb | 2435 | static void print_func_help_header(struct trace_buffer *buf, struct seq_file *m) |
39eaf7ef | 2436 | { |
12883efb | 2437 | print_event_info(buf, m); |
77271ce4 | 2438 | seq_puts(m, "# TASK-PID CPU# TIMESTAMP FUNCTION\n"); |
a6168353 | 2439 | seq_puts(m, "# | | | | |\n"); |
bc0c38d1 SR |
2440 | } |
2441 | ||
12883efb | 2442 | static void print_func_help_header_irq(struct trace_buffer *buf, struct seq_file *m) |
77271ce4 | 2443 | { |
12883efb | 2444 | print_event_info(buf, m); |
77271ce4 SR |
2445 | seq_puts(m, "# _-----=> irqs-off\n"); |
2446 | seq_puts(m, "# / _----=> need-resched\n"); | |
2447 | seq_puts(m, "# | / _---=> hardirq/softirq\n"); | |
2448 | seq_puts(m, "# || / _--=> preempt-depth\n"); | |
2449 | seq_puts(m, "# ||| / delay\n"); | |
2450 | seq_puts(m, "# TASK-PID CPU# |||| TIMESTAMP FUNCTION\n"); | |
2451 | seq_puts(m, "# | | | |||| | |\n"); | |
2452 | } | |
bc0c38d1 | 2453 | |
62b915f1 | 2454 | void |
bc0c38d1 SR |
2455 | print_trace_header(struct seq_file *m, struct trace_iterator *iter) |
2456 | { | |
2457 | unsigned long sym_flags = (trace_flags & TRACE_ITER_SYM_MASK); | |
12883efb SRRH |
2458 | struct trace_buffer *buf = iter->trace_buffer; |
2459 | struct trace_array_cpu *data = per_cpu_ptr(buf->data, buf->cpu); | |
2b6080f2 | 2460 | struct tracer *type = iter->trace; |
39eaf7ef SR |
2461 | unsigned long entries; |
2462 | unsigned long total; | |
bc0c38d1 SR |
2463 | const char *name = "preemption"; |
2464 | ||
d840f718 | 2465 | name = type->name; |
bc0c38d1 | 2466 | |
12883efb | 2467 | get_total_entries(buf, &total, &entries); |
bc0c38d1 | 2468 | |
888b55dc | 2469 | seq_printf(m, "# %s latency trace v1.1.5 on %s\n", |
bc0c38d1 | 2470 | name, UTS_RELEASE); |
888b55dc | 2471 | seq_puts(m, "# -----------------------------------" |
bc0c38d1 | 2472 | "---------------------------------\n"); |
888b55dc | 2473 | seq_printf(m, "# latency: %lu us, #%lu/%lu, CPU#%d |" |
bc0c38d1 | 2474 | " (M:%s VP:%d, KP:%d, SP:%d HP:%d", |
57f50be1 | 2475 | nsecs_to_usecs(data->saved_latency), |
bc0c38d1 | 2476 | entries, |
4c11d7ae | 2477 | total, |
12883efb | 2478 | buf->cpu, |
bc0c38d1 SR |
2479 | #if defined(CONFIG_PREEMPT_NONE) |
2480 | "server", | |
2481 | #elif defined(CONFIG_PREEMPT_VOLUNTARY) | |
2482 | "desktop", | |
b5c21b45 | 2483 | #elif defined(CONFIG_PREEMPT) |
bc0c38d1 SR |
2484 | "preempt", |
2485 | #else | |
2486 | "unknown", | |
2487 | #endif | |
2488 | /* These are reserved for later use */ | |
2489 | 0, 0, 0, 0); | |
2490 | #ifdef CONFIG_SMP | |
2491 | seq_printf(m, " #P:%d)\n", num_online_cpus()); | |
2492 | #else | |
2493 | seq_puts(m, ")\n"); | |
2494 | #endif | |
888b55dc KM |
2495 | seq_puts(m, "# -----------------\n"); |
2496 | seq_printf(m, "# | task: %.16s-%d " | |
bc0c38d1 | 2497 | "(uid:%d nice:%ld policy:%ld rt_prio:%ld)\n", |
d20b92ab EB |
2498 | data->comm, data->pid, |
2499 | from_kuid_munged(seq_user_ns(m), data->uid), data->nice, | |
bc0c38d1 | 2500 | data->policy, data->rt_priority); |
888b55dc | 2501 | seq_puts(m, "# -----------------\n"); |
bc0c38d1 SR |
2502 | |
2503 | if (data->critical_start) { | |
888b55dc | 2504 | seq_puts(m, "# => started at: "); |
214023c3 SR |
2505 | seq_print_ip_sym(&iter->seq, data->critical_start, sym_flags); |
2506 | trace_print_seq(m, &iter->seq); | |
888b55dc | 2507 | seq_puts(m, "\n# => ended at: "); |
214023c3 SR |
2508 | seq_print_ip_sym(&iter->seq, data->critical_end, sym_flags); |
2509 | trace_print_seq(m, &iter->seq); | |
8248ac05 | 2510 | seq_puts(m, "\n#\n"); |
bc0c38d1 SR |
2511 | } |
2512 | ||
888b55dc | 2513 | seq_puts(m, "#\n"); |
bc0c38d1 SR |
2514 | } |
2515 | ||
a309720c SR |
2516 | static void test_cpu_buff_start(struct trace_iterator *iter) |
2517 | { | |
2518 | struct trace_seq *s = &iter->seq; | |
2519 | ||
12ef7d44 SR |
2520 | if (!(trace_flags & TRACE_ITER_ANNOTATE)) |
2521 | return; | |
2522 | ||
2523 | if (!(iter->iter_flags & TRACE_FILE_ANNOTATE)) | |
2524 | return; | |
2525 | ||
4462344e | 2526 | if (cpumask_test_cpu(iter->cpu, iter->started)) |
a309720c SR |
2527 | return; |
2528 | ||
12883efb | 2529 | if (per_cpu_ptr(iter->trace_buffer->data, iter->cpu)->skipped_entries) |
2f26ebd5 SR |
2530 | return; |
2531 | ||
4462344e | 2532 | cpumask_set_cpu(iter->cpu, iter->started); |
b0dfa978 FW |
2533 | |
2534 | /* Don't print started cpu buffer for the first entry of the trace */ | |
2535 | if (iter->idx > 1) | |
2536 | trace_seq_printf(s, "##### CPU %u buffer started ####\n", | |
2537 | iter->cpu); | |
a309720c SR |
2538 | } |
2539 | ||
2c4f035f | 2540 | static enum print_line_t print_trace_fmt(struct trace_iterator *iter) |
bc0c38d1 | 2541 | { |
214023c3 | 2542 | struct trace_seq *s = &iter->seq; |
bc0c38d1 | 2543 | unsigned long sym_flags = (trace_flags & TRACE_ITER_SYM_MASK); |
4e3c3333 | 2544 | struct trace_entry *entry; |
f633cef0 | 2545 | struct trace_event *event; |
bc0c38d1 | 2546 | |
4e3c3333 | 2547 | entry = iter->ent; |
dd0e545f | 2548 | |
a309720c SR |
2549 | test_cpu_buff_start(iter); |
2550 | ||
c4a8e8be | 2551 | event = ftrace_find_event(entry->type); |
bc0c38d1 | 2552 | |
c4a8e8be | 2553 | if (trace_flags & TRACE_ITER_CONTEXT_INFO) { |
27d48be8 SR |
2554 | if (iter->iter_flags & TRACE_FILE_LAT_FMT) { |
2555 | if (!trace_print_lat_context(iter)) | |
2556 | goto partial; | |
2557 | } else { | |
2558 | if (!trace_print_context(iter)) | |
2559 | goto partial; | |
2560 | } | |
c4a8e8be | 2561 | } |
bc0c38d1 | 2562 | |
268ccda0 | 2563 | if (event) |
a9a57763 | 2564 | return event->funcs->trace(iter, sym_flags, event); |
d9793bd8 ACM |
2565 | |
2566 | if (!trace_seq_printf(s, "Unknown type %d\n", entry->type)) | |
2567 | goto partial; | |
02b67518 | 2568 | |
2c4f035f | 2569 | return TRACE_TYPE_HANDLED; |
d9793bd8 ACM |
2570 | partial: |
2571 | return TRACE_TYPE_PARTIAL_LINE; | |
bc0c38d1 SR |
2572 | } |
2573 | ||
2c4f035f | 2574 | static enum print_line_t print_raw_fmt(struct trace_iterator *iter) |
f9896bf3 IM |
2575 | { |
2576 | struct trace_seq *s = &iter->seq; | |
2577 | struct trace_entry *entry; | |
f633cef0 | 2578 | struct trace_event *event; |
f9896bf3 IM |
2579 | |
2580 | entry = iter->ent; | |
dd0e545f | 2581 | |
c4a8e8be | 2582 | if (trace_flags & TRACE_ITER_CONTEXT_INFO) { |
d9793bd8 ACM |
2583 | if (!trace_seq_printf(s, "%d %d %llu ", |
2584 | entry->pid, iter->cpu, iter->ts)) | |
2585 | goto partial; | |
c4a8e8be | 2586 | } |
f9896bf3 | 2587 | |
f633cef0 | 2588 | event = ftrace_find_event(entry->type); |
268ccda0 | 2589 | if (event) |
a9a57763 | 2590 | return event->funcs->raw(iter, 0, event); |
d9793bd8 ACM |
2591 | |
2592 | if (!trace_seq_printf(s, "%d ?\n", entry->type)) | |
2593 | goto partial; | |
777e208d | 2594 | |
2c4f035f | 2595 | return TRACE_TYPE_HANDLED; |
d9793bd8 ACM |
2596 | partial: |
2597 | return TRACE_TYPE_PARTIAL_LINE; | |
f9896bf3 IM |
2598 | } |
2599 | ||
2c4f035f | 2600 | static enum print_line_t print_hex_fmt(struct trace_iterator *iter) |
5e3ca0ec IM |
2601 | { |
2602 | struct trace_seq *s = &iter->seq; | |
2603 | unsigned char newline = '\n'; | |
2604 | struct trace_entry *entry; | |
f633cef0 | 2605 | struct trace_event *event; |
5e3ca0ec IM |
2606 | |
2607 | entry = iter->ent; | |
dd0e545f | 2608 | |
c4a8e8be FW |
2609 | if (trace_flags & TRACE_ITER_CONTEXT_INFO) { |
2610 | SEQ_PUT_HEX_FIELD_RET(s, entry->pid); | |
2611 | SEQ_PUT_HEX_FIELD_RET(s, iter->cpu); | |
2612 | SEQ_PUT_HEX_FIELD_RET(s, iter->ts); | |
2613 | } | |
5e3ca0ec | 2614 | |
f633cef0 | 2615 | event = ftrace_find_event(entry->type); |
268ccda0 | 2616 | if (event) { |
a9a57763 | 2617 | enum print_line_t ret = event->funcs->hex(iter, 0, event); |
d9793bd8 ACM |
2618 | if (ret != TRACE_TYPE_HANDLED) |
2619 | return ret; | |
2620 | } | |
7104f300 | 2621 | |
5e3ca0ec IM |
2622 | SEQ_PUT_FIELD_RET(s, newline); |
2623 | ||
2c4f035f | 2624 | return TRACE_TYPE_HANDLED; |
5e3ca0ec IM |
2625 | } |
2626 | ||
2c4f035f | 2627 | static enum print_line_t print_bin_fmt(struct trace_iterator *iter) |
cb0f12aa IM |
2628 | { |
2629 | struct trace_seq *s = &iter->seq; | |
2630 | struct trace_entry *entry; | |
f633cef0 | 2631 | struct trace_event *event; |
cb0f12aa IM |
2632 | |
2633 | entry = iter->ent; | |
dd0e545f | 2634 | |
c4a8e8be FW |
2635 | if (trace_flags & TRACE_ITER_CONTEXT_INFO) { |
2636 | SEQ_PUT_FIELD_RET(s, entry->pid); | |
1830b52d | 2637 | SEQ_PUT_FIELD_RET(s, iter->cpu); |
c4a8e8be FW |
2638 | SEQ_PUT_FIELD_RET(s, iter->ts); |
2639 | } | |
cb0f12aa | 2640 | |
f633cef0 | 2641 | event = ftrace_find_event(entry->type); |
a9a57763 SR |
2642 | return event ? event->funcs->binary(iter, 0, event) : |
2643 | TRACE_TYPE_HANDLED; | |
cb0f12aa IM |
2644 | } |
2645 | ||
62b915f1 | 2646 | int trace_empty(struct trace_iterator *iter) |
bc0c38d1 | 2647 | { |
6d158a81 | 2648 | struct ring_buffer_iter *buf_iter; |
bc0c38d1 SR |
2649 | int cpu; |
2650 | ||
9aba60fe | 2651 | /* If we are looking at one CPU buffer, only check that one */ |
ae3b5093 | 2652 | if (iter->cpu_file != RING_BUFFER_ALL_CPUS) { |
9aba60fe | 2653 | cpu = iter->cpu_file; |
6d158a81 SR |
2654 | buf_iter = trace_buffer_iter(iter, cpu); |
2655 | if (buf_iter) { | |
2656 | if (!ring_buffer_iter_empty(buf_iter)) | |
9aba60fe SR |
2657 | return 0; |
2658 | } else { | |
12883efb | 2659 | if (!ring_buffer_empty_cpu(iter->trace_buffer->buffer, cpu)) |
9aba60fe SR |
2660 | return 0; |
2661 | } | |
2662 | return 1; | |
2663 | } | |
2664 | ||
ab46428c | 2665 | for_each_tracing_cpu(cpu) { |
6d158a81 SR |
2666 | buf_iter = trace_buffer_iter(iter, cpu); |
2667 | if (buf_iter) { | |
2668 | if (!ring_buffer_iter_empty(buf_iter)) | |
d769041f SR |
2669 | return 0; |
2670 | } else { | |
12883efb | 2671 | if (!ring_buffer_empty_cpu(iter->trace_buffer->buffer, cpu)) |
d769041f SR |
2672 | return 0; |
2673 | } | |
bc0c38d1 | 2674 | } |
d769041f | 2675 | |
797d3712 | 2676 | return 1; |
bc0c38d1 SR |
2677 | } |
2678 | ||
4f535968 | 2679 | /* Called with trace_event_read_lock() held. */ |
955b61e5 | 2680 | enum print_line_t print_trace_line(struct trace_iterator *iter) |
f9896bf3 | 2681 | { |
2c4f035f FW |
2682 | enum print_line_t ret; |
2683 | ||
ee5e51f5 JO |
2684 | if (iter->lost_events && |
2685 | !trace_seq_printf(&iter->seq, "CPU:%d [LOST %lu EVENTS]\n", | |
2686 | iter->cpu, iter->lost_events)) | |
2687 | return TRACE_TYPE_PARTIAL_LINE; | |
bc21b478 | 2688 | |
2c4f035f FW |
2689 | if (iter->trace && iter->trace->print_line) { |
2690 | ret = iter->trace->print_line(iter); | |
2691 | if (ret != TRACE_TYPE_UNHANDLED) | |
2692 | return ret; | |
2693 | } | |
72829bc3 | 2694 | |
09ae7234 SRRH |
2695 | if (iter->ent->type == TRACE_BPUTS && |
2696 | trace_flags & TRACE_ITER_PRINTK && | |
2697 | trace_flags & TRACE_ITER_PRINTK_MSGONLY) | |
2698 | return trace_print_bputs_msg_only(iter); | |
2699 | ||
48ead020 FW |
2700 | if (iter->ent->type == TRACE_BPRINT && |
2701 | trace_flags & TRACE_ITER_PRINTK && | |
2702 | trace_flags & TRACE_ITER_PRINTK_MSGONLY) | |
5ef841f6 | 2703 | return trace_print_bprintk_msg_only(iter); |
48ead020 | 2704 | |
66896a85 FW |
2705 | if (iter->ent->type == TRACE_PRINT && |
2706 | trace_flags & TRACE_ITER_PRINTK && | |
2707 | trace_flags & TRACE_ITER_PRINTK_MSGONLY) | |
5ef841f6 | 2708 | return trace_print_printk_msg_only(iter); |
66896a85 | 2709 | |
cb0f12aa IM |
2710 | if (trace_flags & TRACE_ITER_BIN) |
2711 | return print_bin_fmt(iter); | |
2712 | ||
5e3ca0ec IM |
2713 | if (trace_flags & TRACE_ITER_HEX) |
2714 | return print_hex_fmt(iter); | |
2715 | ||
f9896bf3 IM |
2716 | if (trace_flags & TRACE_ITER_RAW) |
2717 | return print_raw_fmt(iter); | |
2718 | ||
f9896bf3 IM |
2719 | return print_trace_fmt(iter); |
2720 | } | |
2721 | ||
7e9a49ef JO |
2722 | void trace_latency_header(struct seq_file *m) |
2723 | { | |
2724 | struct trace_iterator *iter = m->private; | |
2725 | ||
2726 | /* print nothing if the buffers are empty */ | |
2727 | if (trace_empty(iter)) | |
2728 | return; | |
2729 | ||
2730 | if (iter->iter_flags & TRACE_FILE_LAT_FMT) | |
2731 | print_trace_header(m, iter); | |
2732 | ||
2733 | if (!(trace_flags & TRACE_ITER_VERBOSE)) | |
2734 | print_lat_help_header(m); | |
2735 | } | |
2736 | ||
62b915f1 JO |
2737 | void trace_default_header(struct seq_file *m) |
2738 | { | |
2739 | struct trace_iterator *iter = m->private; | |
2740 | ||
f56e7f8e JO |
2741 | if (!(trace_flags & TRACE_ITER_CONTEXT_INFO)) |
2742 | return; | |
2743 | ||
62b915f1 JO |
2744 | if (iter->iter_flags & TRACE_FILE_LAT_FMT) { |
2745 | /* print nothing if the buffers are empty */ | |
2746 | if (trace_empty(iter)) | |
2747 | return; | |
2748 | print_trace_header(m, iter); | |
2749 | if (!(trace_flags & TRACE_ITER_VERBOSE)) | |
2750 | print_lat_help_header(m); | |
2751 | } else { | |
77271ce4 SR |
2752 | if (!(trace_flags & TRACE_ITER_VERBOSE)) { |
2753 | if (trace_flags & TRACE_ITER_IRQ_INFO) | |
12883efb | 2754 | print_func_help_header_irq(iter->trace_buffer, m); |
77271ce4 | 2755 | else |
12883efb | 2756 | print_func_help_header(iter->trace_buffer, m); |
77271ce4 | 2757 | } |
62b915f1 JO |
2758 | } |
2759 | } | |
2760 | ||
e0a413f6 SR |
2761 | static void test_ftrace_alive(struct seq_file *m) |
2762 | { | |
2763 | if (!ftrace_is_dead()) | |
2764 | return; | |
2765 | seq_printf(m, "# WARNING: FUNCTION TRACING IS CORRUPTED\n"); | |
2766 | seq_printf(m, "# MAY BE MISSING FUNCTION EVENTS\n"); | |
2767 | } | |
2768 | ||
d8741e2e | 2769 | #ifdef CONFIG_TRACER_MAX_TRACE |
f1affcaa | 2770 | static void show_snapshot_main_help(struct seq_file *m) |
d8741e2e | 2771 | { |
d8741e2e SRRH |
2772 | seq_printf(m, "# echo 0 > snapshot : Clears and frees snapshot buffer\n"); |
2773 | seq_printf(m, "# echo 1 > snapshot : Allocates snapshot buffer, if not already allocated.\n"); | |
2774 | seq_printf(m, "# Takes a snapshot of the main buffer.\n"); | |
2775 | seq_printf(m, "# echo 2 > snapshot : Clears snapshot buffer (but does not allocate)\n"); | |
2776 | seq_printf(m, "# (Doesn't have to be '2' works with any number that\n"); | |
2777 | seq_printf(m, "# is not a '0' or '1')\n"); | |
2778 | } | |
f1affcaa SRRH |
2779 | |
2780 | static void show_snapshot_percpu_help(struct seq_file *m) | |
2781 | { | |
2782 | seq_printf(m, "# echo 0 > snapshot : Invalid for per_cpu snapshot file.\n"); | |
2783 | #ifdef CONFIG_RING_BUFFER_ALLOW_SWAP | |
2784 | seq_printf(m, "# echo 1 > snapshot : Allocates snapshot buffer, if not already allocated.\n"); | |
2785 | seq_printf(m, "# Takes a snapshot of the main buffer for this cpu.\n"); | |
2786 | #else | |
2787 | seq_printf(m, "# echo 1 > snapshot : Not supported with this kernel.\n"); | |
2788 | seq_printf(m, "# Must use main snapshot file to allocate.\n"); | |
2789 | #endif | |
2790 | seq_printf(m, "# echo 2 > snapshot : Clears this cpu's snapshot buffer (but does not allocate)\n"); | |
2791 | seq_printf(m, "# (Doesn't have to be '2' works with any number that\n"); | |
2792 | seq_printf(m, "# is not a '0' or '1')\n"); | |
2793 | } | |
2794 | ||
d8741e2e SRRH |
2795 | static void print_snapshot_help(struct seq_file *m, struct trace_iterator *iter) |
2796 | { | |
45ad21ca | 2797 | if (iter->tr->allocated_snapshot) |
d8741e2e SRRH |
2798 | seq_printf(m, "#\n# * Snapshot is allocated *\n#\n"); |
2799 | else | |
2800 | seq_printf(m, "#\n# * Snapshot is freed *\n#\n"); | |
2801 | ||
2802 | seq_printf(m, "# Snapshot commands:\n"); | |
f1affcaa SRRH |
2803 | if (iter->cpu_file == RING_BUFFER_ALL_CPUS) |
2804 | show_snapshot_main_help(m); | |
2805 | else | |
2806 | show_snapshot_percpu_help(m); | |
d8741e2e SRRH |
2807 | } |
2808 | #else | |
2809 | /* Should never be called */ | |
2810 | static inline void print_snapshot_help(struct seq_file *m, struct trace_iterator *iter) { } | |
2811 | #endif | |
2812 | ||
bc0c38d1 SR |
2813 | static int s_show(struct seq_file *m, void *v) |
2814 | { | |
2815 | struct trace_iterator *iter = v; | |
a63ce5b3 | 2816 | int ret; |
bc0c38d1 SR |
2817 | |
2818 | if (iter->ent == NULL) { | |
2819 | if (iter->tr) { | |
2820 | seq_printf(m, "# tracer: %s\n", iter->trace->name); | |
2821 | seq_puts(m, "#\n"); | |
e0a413f6 | 2822 | test_ftrace_alive(m); |
bc0c38d1 | 2823 | } |
d8741e2e SRRH |
2824 | if (iter->snapshot && trace_empty(iter)) |
2825 | print_snapshot_help(m, iter); | |
2826 | else if (iter->trace && iter->trace->print_header) | |
8bba1bf5 | 2827 | iter->trace->print_header(m); |
62b915f1 JO |
2828 | else |
2829 | trace_default_header(m); | |
2830 | ||
a63ce5b3 SR |
2831 | } else if (iter->leftover) { |
2832 | /* | |
2833 | * If we filled the seq_file buffer earlier, we | |
2834 | * want to just show it now. | |
2835 | */ | |
2836 | ret = trace_print_seq(m, &iter->seq); | |
2837 | ||
2838 | /* ret should this time be zero, but you never know */ | |
2839 | iter->leftover = ret; | |
2840 | ||
bc0c38d1 | 2841 | } else { |
f9896bf3 | 2842 | print_trace_line(iter); |
a63ce5b3 SR |
2843 | ret = trace_print_seq(m, &iter->seq); |
2844 | /* | |
2845 | * If we overflow the seq_file buffer, then it will | |
2846 | * ask us for this data again at start up. | |
2847 | * Use that instead. | |
2848 | * ret is 0 if seq_file write succeeded. | |
2849 | * -1 otherwise. | |
2850 | */ | |
2851 | iter->leftover = ret; | |
bc0c38d1 SR |
2852 | } |
2853 | ||
2854 | return 0; | |
2855 | } | |
2856 | ||
88e9d34c | 2857 | static const struct seq_operations tracer_seq_ops = { |
4bf39a94 IM |
2858 | .start = s_start, |
2859 | .next = s_next, | |
2860 | .stop = s_stop, | |
2861 | .show = s_show, | |
bc0c38d1 SR |
2862 | }; |
2863 | ||
e309b41d | 2864 | static struct trace_iterator * |
ff451961 SRRH |
2865 | __tracing_open(struct trace_array *tr, struct trace_cpu *tc, |
2866 | struct inode *inode, struct file *file, bool snapshot) | |
bc0c38d1 SR |
2867 | { |
2868 | struct trace_iterator *iter; | |
50e18b94 | 2869 | int cpu; |
bc0c38d1 | 2870 | |
85a2f9b4 SR |
2871 | if (tracing_disabled) |
2872 | return ERR_PTR(-ENODEV); | |
60a11774 | 2873 | |
50e18b94 | 2874 | iter = __seq_open_private(file, &tracer_seq_ops, sizeof(*iter)); |
85a2f9b4 SR |
2875 | if (!iter) |
2876 | return ERR_PTR(-ENOMEM); | |
bc0c38d1 | 2877 | |
6d158a81 SR |
2878 | iter->buffer_iter = kzalloc(sizeof(*iter->buffer_iter) * num_possible_cpus(), |
2879 | GFP_KERNEL); | |
93574fcc DC |
2880 | if (!iter->buffer_iter) |
2881 | goto release; | |
2882 | ||
d7350c3f FW |
2883 | /* |
2884 | * We make a copy of the current tracer to avoid concurrent | |
2885 | * changes on it while we are reading. | |
2886 | */ | |
bc0c38d1 | 2887 | mutex_lock(&trace_types_lock); |
d7350c3f | 2888 | iter->trace = kzalloc(sizeof(*iter->trace), GFP_KERNEL); |
85a2f9b4 | 2889 | if (!iter->trace) |
d7350c3f | 2890 | goto fail; |
85a2f9b4 | 2891 | |
2b6080f2 | 2892 | *iter->trace = *tr->current_trace; |
d7350c3f | 2893 | |
79f55997 | 2894 | if (!zalloc_cpumask_var(&iter->started, GFP_KERNEL)) |
b0dfa978 FW |
2895 | goto fail; |
2896 | ||
12883efb SRRH |
2897 | iter->tr = tr; |
2898 | ||
2899 | #ifdef CONFIG_TRACER_MAX_TRACE | |
2b6080f2 SR |
2900 | /* Currently only the top directory has a snapshot */ |
2901 | if (tr->current_trace->print_max || snapshot) | |
12883efb | 2902 | iter->trace_buffer = &tr->max_buffer; |
bc0c38d1 | 2903 | else |
12883efb SRRH |
2904 | #endif |
2905 | iter->trace_buffer = &tr->trace_buffer; | |
debdd57f | 2906 | iter->snapshot = snapshot; |
bc0c38d1 | 2907 | iter->pos = -1; |
d7350c3f | 2908 | mutex_init(&iter->mutex); |
2b6080f2 | 2909 | iter->cpu_file = tc->cpu; |
bc0c38d1 | 2910 | |
8bba1bf5 MM |
2911 | /* Notify the tracer early; before we stop tracing. */ |
2912 | if (iter->trace && iter->trace->open) | |
a93751ca | 2913 | iter->trace->open(iter); |
8bba1bf5 | 2914 | |
12ef7d44 | 2915 | /* Annotate start of buffers if we had overruns */ |
12883efb | 2916 | if (ring_buffer_overruns(iter->trace_buffer->buffer)) |
12ef7d44 SR |
2917 | iter->iter_flags |= TRACE_FILE_ANNOTATE; |
2918 | ||
8be0709f DS |
2919 | /* Output in nanoseconds only if we are using a clock in nanoseconds. */ |
2920 | if (trace_clocks[trace_clock_id].in_ns) | |
2921 | iter->iter_flags |= TRACE_FILE_TIME_IN_NS; | |
2922 | ||
debdd57f HT |
2923 | /* stop the trace while dumping if we are not opening "snapshot" */ |
2924 | if (!iter->snapshot) | |
2b6080f2 | 2925 | tracing_stop_tr(tr); |
2f26ebd5 | 2926 | |
ae3b5093 | 2927 | if (iter->cpu_file == RING_BUFFER_ALL_CPUS) { |
b04cc6b1 | 2928 | for_each_tracing_cpu(cpu) { |
b04cc6b1 | 2929 | iter->buffer_iter[cpu] = |
12883efb | 2930 | ring_buffer_read_prepare(iter->trace_buffer->buffer, cpu); |
72c9ddfd DM |
2931 | } |
2932 | ring_buffer_read_prepare_sync(); | |
2933 | for_each_tracing_cpu(cpu) { | |
2934 | ring_buffer_read_start(iter->buffer_iter[cpu]); | |
2f26ebd5 | 2935 | tracing_iter_reset(iter, cpu); |
b04cc6b1 FW |
2936 | } |
2937 | } else { | |
2938 | cpu = iter->cpu_file; | |
3928a8a2 | 2939 | iter->buffer_iter[cpu] = |
12883efb | 2940 | ring_buffer_read_prepare(iter->trace_buffer->buffer, cpu); |
72c9ddfd DM |
2941 | ring_buffer_read_prepare_sync(); |
2942 | ring_buffer_read_start(iter->buffer_iter[cpu]); | |
2f26ebd5 | 2943 | tracing_iter_reset(iter, cpu); |
3928a8a2 SR |
2944 | } |
2945 | ||
bc0c38d1 SR |
2946 | mutex_unlock(&trace_types_lock); |
2947 | ||
bc0c38d1 | 2948 | return iter; |
3928a8a2 | 2949 | |
d7350c3f | 2950 | fail: |
3928a8a2 | 2951 | mutex_unlock(&trace_types_lock); |
d7350c3f | 2952 | kfree(iter->trace); |
6d158a81 | 2953 | kfree(iter->buffer_iter); |
93574fcc | 2954 | release: |
50e18b94 JO |
2955 | seq_release_private(inode, file); |
2956 | return ERR_PTR(-ENOMEM); | |
bc0c38d1 SR |
2957 | } |
2958 | ||
2959 | int tracing_open_generic(struct inode *inode, struct file *filp) | |
2960 | { | |
60a11774 SR |
2961 | if (tracing_disabled) |
2962 | return -ENODEV; | |
2963 | ||
bc0c38d1 SR |
2964 | filp->private_data = inode->i_private; |
2965 | return 0; | |
2966 | } | |
2967 | ||
4fd27358 | 2968 | static int tracing_release(struct inode *inode, struct file *file) |
bc0c38d1 | 2969 | { |
907f2784 | 2970 | struct seq_file *m = file->private_data; |
4acd4d00 | 2971 | struct trace_iterator *iter; |
2b6080f2 | 2972 | struct trace_array *tr; |
3928a8a2 | 2973 | int cpu; |
bc0c38d1 | 2974 | |
ff451961 SRRH |
2975 | /* Writes do not use seq_file, need to grab tr from inode */ |
2976 | if (!(file->f_mode & FMODE_READ)) { | |
2977 | struct trace_cpu *tc = inode->i_private; | |
2978 | ||
2979 | trace_array_put(tc->tr); | |
4acd4d00 | 2980 | return 0; |
ff451961 | 2981 | } |
4acd4d00 SR |
2982 | |
2983 | iter = m->private; | |
12883efb | 2984 | tr = iter->tr; |
ff451961 | 2985 | trace_array_put(tr); |
4acd4d00 | 2986 | |
bc0c38d1 | 2987 | mutex_lock(&trace_types_lock); |
a695cb58 | 2988 | |
3928a8a2 SR |
2989 | for_each_tracing_cpu(cpu) { |
2990 | if (iter->buffer_iter[cpu]) | |
2991 | ring_buffer_read_finish(iter->buffer_iter[cpu]); | |
2992 | } | |
2993 | ||
bc0c38d1 SR |
2994 | if (iter->trace && iter->trace->close) |
2995 | iter->trace->close(iter); | |
2996 | ||
debdd57f HT |
2997 | if (!iter->snapshot) |
2998 | /* reenable tracing if it was previously enabled */ | |
2b6080f2 | 2999 | tracing_start_tr(tr); |
bc0c38d1 SR |
3000 | mutex_unlock(&trace_types_lock); |
3001 | ||
d7350c3f | 3002 | mutex_destroy(&iter->mutex); |
b0dfa978 | 3003 | free_cpumask_var(iter->started); |
d7350c3f | 3004 | kfree(iter->trace); |
6d158a81 | 3005 | kfree(iter->buffer_iter); |
50e18b94 | 3006 | seq_release_private(inode, file); |
ff451961 | 3007 | |
bc0c38d1 SR |
3008 | return 0; |
3009 | } | |
3010 | ||
3011 | static int tracing_open(struct inode *inode, struct file *file) | |
3012 | { | |
ff451961 SRRH |
3013 | struct trace_cpu *tc = inode->i_private; |
3014 | struct trace_array *tr = tc->tr; | |
85a2f9b4 SR |
3015 | struct trace_iterator *iter; |
3016 | int ret = 0; | |
bc0c38d1 | 3017 | |
ff451961 SRRH |
3018 | if (trace_array_get(tr) < 0) |
3019 | return -ENODEV; | |
3020 | ||
4acd4d00 SR |
3021 | /* If this file was open for write, then erase contents */ |
3022 | if ((file->f_mode & FMODE_WRITE) && | |
8650ae32 | 3023 | (file->f_flags & O_TRUNC)) { |
2b6080f2 | 3024 | if (tc->cpu == RING_BUFFER_ALL_CPUS) |
12883efb | 3025 | tracing_reset_online_cpus(&tr->trace_buffer); |
4acd4d00 | 3026 | else |
12883efb | 3027 | tracing_reset(&tr->trace_buffer, tc->cpu); |
4acd4d00 | 3028 | } |
bc0c38d1 | 3029 | |
4acd4d00 | 3030 | if (file->f_mode & FMODE_READ) { |
ff451961 | 3031 | iter = __tracing_open(tr, tc, inode, file, false); |
4acd4d00 SR |
3032 | if (IS_ERR(iter)) |
3033 | ret = PTR_ERR(iter); | |
3034 | else if (trace_flags & TRACE_ITER_LATENCY_FMT) | |
3035 | iter->iter_flags |= TRACE_FILE_LAT_FMT; | |
3036 | } | |
ff451961 SRRH |
3037 | |
3038 | if (ret < 0) | |
3039 | trace_array_put(tr); | |
3040 | ||
bc0c38d1 SR |
3041 | return ret; |
3042 | } | |
3043 | ||
e309b41d | 3044 | static void * |
bc0c38d1 SR |
3045 | t_next(struct seq_file *m, void *v, loff_t *pos) |
3046 | { | |
f129e965 | 3047 | struct tracer *t = v; |
bc0c38d1 SR |
3048 | |
3049 | (*pos)++; | |
3050 | ||
3051 | if (t) | |
3052 | t = t->next; | |
3053 | ||
bc0c38d1 SR |
3054 | return t; |
3055 | } | |
3056 | ||
3057 | static void *t_start(struct seq_file *m, loff_t *pos) | |
3058 | { | |
f129e965 | 3059 | struct tracer *t; |
bc0c38d1 SR |
3060 | loff_t l = 0; |
3061 | ||
3062 | mutex_lock(&trace_types_lock); | |
f129e965 | 3063 | for (t = trace_types; t && l < *pos; t = t_next(m, t, &l)) |
bc0c38d1 SR |
3064 | ; |
3065 | ||
3066 | return t; | |
3067 | } | |
3068 | ||
3069 | static void t_stop(struct seq_file *m, void *p) | |
3070 | { | |
3071 | mutex_unlock(&trace_types_lock); | |
3072 | } | |
3073 | ||
3074 | static int t_show(struct seq_file *m, void *v) | |
3075 | { | |
3076 | struct tracer *t = v; | |
3077 | ||
3078 | if (!t) | |
3079 | return 0; | |
3080 | ||
3081 | seq_printf(m, "%s", t->name); | |
3082 | if (t->next) | |
3083 | seq_putc(m, ' '); | |
3084 | else | |
3085 | seq_putc(m, '\n'); | |
3086 | ||
3087 | return 0; | |
3088 | } | |
3089 | ||
88e9d34c | 3090 | static const struct seq_operations show_traces_seq_ops = { |
4bf39a94 IM |
3091 | .start = t_start, |
3092 | .next = t_next, | |
3093 | .stop = t_stop, | |
3094 | .show = t_show, | |
bc0c38d1 SR |
3095 | }; |
3096 | ||
3097 | static int show_traces_open(struct inode *inode, struct file *file) | |
3098 | { | |
60a11774 SR |
3099 | if (tracing_disabled) |
3100 | return -ENODEV; | |
3101 | ||
f129e965 | 3102 | return seq_open(file, &show_traces_seq_ops); |
bc0c38d1 SR |
3103 | } |
3104 | ||
4acd4d00 SR |
3105 | static ssize_t |
3106 | tracing_write_stub(struct file *filp, const char __user *ubuf, | |
3107 | size_t count, loff_t *ppos) | |
3108 | { | |
3109 | return count; | |
3110 | } | |
3111 | ||
364829b1 SP |
3112 | static loff_t tracing_seek(struct file *file, loff_t offset, int origin) |
3113 | { | |
3114 | if (file->f_mode & FMODE_READ) | |
3115 | return seq_lseek(file, offset, origin); | |
3116 | else | |
3117 | return 0; | |
3118 | } | |
3119 | ||
5e2336a0 | 3120 | static const struct file_operations tracing_fops = { |
4bf39a94 IM |
3121 | .open = tracing_open, |
3122 | .read = seq_read, | |
4acd4d00 | 3123 | .write = tracing_write_stub, |
364829b1 | 3124 | .llseek = tracing_seek, |
4bf39a94 | 3125 | .release = tracing_release, |
bc0c38d1 SR |
3126 | }; |
3127 | ||
5e2336a0 | 3128 | static const struct file_operations show_traces_fops = { |
c7078de1 IM |
3129 | .open = show_traces_open, |
3130 | .read = seq_read, | |
3131 | .release = seq_release, | |
b444786f | 3132 | .llseek = seq_lseek, |
c7078de1 IM |
3133 | }; |
3134 | ||
36dfe925 IM |
3135 | /* |
3136 | * Only trace on a CPU if the bitmask is set: | |
3137 | */ | |
9e01c1b7 | 3138 | static cpumask_var_t tracing_cpumask; |
36dfe925 IM |
3139 | |
3140 | /* | |
3141 | * The tracer itself will not take this lock, but still we want | |
3142 | * to provide a consistent cpumask to user-space: | |
3143 | */ | |
3144 | static DEFINE_MUTEX(tracing_cpumask_update_lock); | |
3145 | ||
3146 | /* | |
3147 | * Temporary storage for the character representation of the | |
3148 | * CPU bitmask (and one more byte for the newline): | |
3149 | */ | |
3150 | static char mask_str[NR_CPUS + 1]; | |
3151 | ||
c7078de1 IM |
3152 | static ssize_t |
3153 | tracing_cpumask_read(struct file *filp, char __user *ubuf, | |
3154 | size_t count, loff_t *ppos) | |
3155 | { | |
36dfe925 | 3156 | int len; |
c7078de1 IM |
3157 | |
3158 | mutex_lock(&tracing_cpumask_update_lock); | |
36dfe925 | 3159 | |
9e01c1b7 | 3160 | len = cpumask_scnprintf(mask_str, count, tracing_cpumask); |
36dfe925 IM |
3161 | if (count - len < 2) { |
3162 | count = -EINVAL; | |
3163 | goto out_err; | |
3164 | } | |
3165 | len += sprintf(mask_str + len, "\n"); | |
3166 | count = simple_read_from_buffer(ubuf, count, ppos, mask_str, NR_CPUS+1); | |
3167 | ||
3168 | out_err: | |
c7078de1 IM |
3169 | mutex_unlock(&tracing_cpumask_update_lock); |
3170 | ||
3171 | return count; | |
3172 | } | |
3173 | ||
3174 | static ssize_t | |
3175 | tracing_cpumask_write(struct file *filp, const char __user *ubuf, | |
3176 | size_t count, loff_t *ppos) | |
3177 | { | |
2b6080f2 | 3178 | struct trace_array *tr = filp->private_data; |
9e01c1b7 | 3179 | cpumask_var_t tracing_cpumask_new; |
2b6080f2 | 3180 | int err, cpu; |
9e01c1b7 RR |
3181 | |
3182 | if (!alloc_cpumask_var(&tracing_cpumask_new, GFP_KERNEL)) | |
3183 | return -ENOMEM; | |
c7078de1 | 3184 | |
9e01c1b7 | 3185 | err = cpumask_parse_user(ubuf, count, tracing_cpumask_new); |
c7078de1 | 3186 | if (err) |
36dfe925 IM |
3187 | goto err_unlock; |
3188 | ||
215368e8 LZ |
3189 | mutex_lock(&tracing_cpumask_update_lock); |
3190 | ||
a5e25883 | 3191 | local_irq_disable(); |
0199c4e6 | 3192 | arch_spin_lock(&ftrace_max_lock); |
ab46428c | 3193 | for_each_tracing_cpu(cpu) { |
36dfe925 IM |
3194 | /* |
3195 | * Increase/decrease the disabled counter if we are | |
3196 | * about to flip a bit in the cpumask: | |
3197 | */ | |
9e01c1b7 RR |
3198 | if (cpumask_test_cpu(cpu, tracing_cpumask) && |
3199 | !cpumask_test_cpu(cpu, tracing_cpumask_new)) { | |
12883efb SRRH |
3200 | atomic_inc(&per_cpu_ptr(tr->trace_buffer.data, cpu)->disabled); |
3201 | ring_buffer_record_disable_cpu(tr->trace_buffer.buffer, cpu); | |
36dfe925 | 3202 | } |
9e01c1b7 RR |
3203 | if (!cpumask_test_cpu(cpu, tracing_cpumask) && |
3204 | cpumask_test_cpu(cpu, tracing_cpumask_new)) { | |
12883efb SRRH |
3205 | atomic_dec(&per_cpu_ptr(tr->trace_buffer.data, cpu)->disabled); |
3206 | ring_buffer_record_enable_cpu(tr->trace_buffer.buffer, cpu); | |
36dfe925 IM |
3207 | } |
3208 | } | |
0199c4e6 | 3209 | arch_spin_unlock(&ftrace_max_lock); |
a5e25883 | 3210 | local_irq_enable(); |
36dfe925 | 3211 | |
9e01c1b7 | 3212 | cpumask_copy(tracing_cpumask, tracing_cpumask_new); |
36dfe925 IM |
3213 | |
3214 | mutex_unlock(&tracing_cpumask_update_lock); | |
9e01c1b7 | 3215 | free_cpumask_var(tracing_cpumask_new); |
c7078de1 IM |
3216 | |
3217 | return count; | |
36dfe925 IM |
3218 | |
3219 | err_unlock: | |
215368e8 | 3220 | free_cpumask_var(tracing_cpumask_new); |
36dfe925 IM |
3221 | |
3222 | return err; | |
c7078de1 IM |
3223 | } |
3224 | ||
5e2336a0 | 3225 | static const struct file_operations tracing_cpumask_fops = { |
c7078de1 IM |
3226 | .open = tracing_open_generic, |
3227 | .read = tracing_cpumask_read, | |
3228 | .write = tracing_cpumask_write, | |
b444786f | 3229 | .llseek = generic_file_llseek, |
bc0c38d1 SR |
3230 | }; |
3231 | ||
fdb372ed | 3232 | static int tracing_trace_options_show(struct seq_file *m, void *v) |
bc0c38d1 | 3233 | { |
d8e83d26 | 3234 | struct tracer_opt *trace_opts; |
2b6080f2 | 3235 | struct trace_array *tr = m->private; |
d8e83d26 | 3236 | u32 tracer_flags; |
d8e83d26 | 3237 | int i; |
adf9f195 | 3238 | |
d8e83d26 | 3239 | mutex_lock(&trace_types_lock); |
2b6080f2 SR |
3240 | tracer_flags = tr->current_trace->flags->val; |
3241 | trace_opts = tr->current_trace->flags->opts; | |
d8e83d26 | 3242 | |
bc0c38d1 SR |
3243 | for (i = 0; trace_options[i]; i++) { |
3244 | if (trace_flags & (1 << i)) | |
fdb372ed | 3245 | seq_printf(m, "%s\n", trace_options[i]); |
bc0c38d1 | 3246 | else |
fdb372ed | 3247 | seq_printf(m, "no%s\n", trace_options[i]); |
bc0c38d1 SR |
3248 | } |
3249 | ||
adf9f195 FW |
3250 | for (i = 0; trace_opts[i].name; i++) { |
3251 | if (tracer_flags & trace_opts[i].bit) | |
fdb372ed | 3252 | seq_printf(m, "%s\n", trace_opts[i].name); |
adf9f195 | 3253 | else |
fdb372ed | 3254 | seq_printf(m, "no%s\n", trace_opts[i].name); |
adf9f195 | 3255 | } |
d8e83d26 | 3256 | mutex_unlock(&trace_types_lock); |
adf9f195 | 3257 | |
fdb372ed | 3258 | return 0; |
bc0c38d1 | 3259 | } |
bc0c38d1 | 3260 | |
8d18eaaf LZ |
3261 | static int __set_tracer_option(struct tracer *trace, |
3262 | struct tracer_flags *tracer_flags, | |
3263 | struct tracer_opt *opts, int neg) | |
3264 | { | |
3265 | int ret; | |
bc0c38d1 | 3266 | |
8d18eaaf LZ |
3267 | ret = trace->set_flag(tracer_flags->val, opts->bit, !neg); |
3268 | if (ret) | |
3269 | return ret; | |
3270 | ||
3271 | if (neg) | |
3272 | tracer_flags->val &= ~opts->bit; | |
3273 | else | |
3274 | tracer_flags->val |= opts->bit; | |
3275 | return 0; | |
bc0c38d1 SR |
3276 | } |
3277 | ||
adf9f195 FW |
3278 | /* Try to assign a tracer specific option */ |
3279 | static int set_tracer_option(struct tracer *trace, char *cmp, int neg) | |
3280 | { | |
7770841e | 3281 | struct tracer_flags *tracer_flags = trace->flags; |
adf9f195 | 3282 | struct tracer_opt *opts = NULL; |
8d18eaaf | 3283 | int i; |
adf9f195 | 3284 | |
7770841e Z |
3285 | for (i = 0; tracer_flags->opts[i].name; i++) { |
3286 | opts = &tracer_flags->opts[i]; | |
adf9f195 | 3287 | |
8d18eaaf LZ |
3288 | if (strcmp(cmp, opts->name) == 0) |
3289 | return __set_tracer_option(trace, trace->flags, | |
3290 | opts, neg); | |
adf9f195 | 3291 | } |
adf9f195 | 3292 | |
8d18eaaf | 3293 | return -EINVAL; |
adf9f195 FW |
3294 | } |
3295 | ||
613f04a0 SRRH |
3296 | /* Some tracers require overwrite to stay enabled */ |
3297 | int trace_keep_overwrite(struct tracer *tracer, u32 mask, int set) | |
3298 | { | |
3299 | if (tracer->enabled && (mask & TRACE_ITER_OVERWRITE) && !set) | |
3300 | return -1; | |
3301 | ||
3302 | return 0; | |
3303 | } | |
3304 | ||
2b6080f2 | 3305 | int set_tracer_flag(struct trace_array *tr, unsigned int mask, int enabled) |
af4617bd SR |
3306 | { |
3307 | /* do nothing if flag is already set */ | |
3308 | if (!!(trace_flags & mask) == !!enabled) | |
613f04a0 SRRH |
3309 | return 0; |
3310 | ||
3311 | /* Give the tracer a chance to approve the change */ | |
2b6080f2 SR |
3312 | if (tr->current_trace->flag_changed) |
3313 | if (tr->current_trace->flag_changed(tr->current_trace, mask, !!enabled)) | |
613f04a0 | 3314 | return -EINVAL; |
af4617bd SR |
3315 | |
3316 | if (enabled) | |
3317 | trace_flags |= mask; | |
3318 | else | |
3319 | trace_flags &= ~mask; | |
e870e9a1 LZ |
3320 | |
3321 | if (mask == TRACE_ITER_RECORD_CMD) | |
3322 | trace_event_enable_cmd_record(enabled); | |
750912fa | 3323 | |
80902822 | 3324 | if (mask == TRACE_ITER_OVERWRITE) { |
12883efb | 3325 | ring_buffer_change_overwrite(tr->trace_buffer.buffer, enabled); |
80902822 | 3326 | #ifdef CONFIG_TRACER_MAX_TRACE |
12883efb | 3327 | ring_buffer_change_overwrite(tr->max_buffer.buffer, enabled); |
80902822 SRRH |
3328 | #endif |
3329 | } | |
81698831 SR |
3330 | |
3331 | if (mask == TRACE_ITER_PRINTK) | |
3332 | trace_printk_start_stop_comm(enabled); | |
613f04a0 SRRH |
3333 | |
3334 | return 0; | |
af4617bd SR |
3335 | } |
3336 | ||
2b6080f2 | 3337 | static int trace_set_options(struct trace_array *tr, char *option) |
bc0c38d1 | 3338 | { |
8d18eaaf | 3339 | char *cmp; |
bc0c38d1 | 3340 | int neg = 0; |
613f04a0 | 3341 | int ret = -ENODEV; |
bc0c38d1 SR |
3342 | int i; |
3343 | ||
7bcfaf54 | 3344 | cmp = strstrip(option); |
bc0c38d1 | 3345 | |
8d18eaaf | 3346 | if (strncmp(cmp, "no", 2) == 0) { |
bc0c38d1 SR |
3347 | neg = 1; |
3348 | cmp += 2; | |
3349 | } | |
3350 | ||
69d34da2 SRRH |
3351 | mutex_lock(&trace_types_lock); |
3352 | ||
bc0c38d1 | 3353 | for (i = 0; trace_options[i]; i++) { |
8d18eaaf | 3354 | if (strcmp(cmp, trace_options[i]) == 0) { |
2b6080f2 | 3355 | ret = set_tracer_flag(tr, 1 << i, !neg); |
bc0c38d1 SR |
3356 | break; |
3357 | } | |
3358 | } | |
adf9f195 FW |
3359 | |
3360 | /* If no option could be set, test the specific tracer options */ | |
69d34da2 | 3361 | if (!trace_options[i]) |
2b6080f2 | 3362 | ret = set_tracer_option(tr->current_trace, cmp, neg); |
69d34da2 SRRH |
3363 | |
3364 | mutex_unlock(&trace_types_lock); | |
bc0c38d1 | 3365 | |
7bcfaf54 SR |
3366 | return ret; |
3367 | } | |
3368 | ||
3369 | static ssize_t | |
3370 | tracing_trace_options_write(struct file *filp, const char __user *ubuf, | |
3371 | size_t cnt, loff_t *ppos) | |
3372 | { | |
2b6080f2 SR |
3373 | struct seq_file *m = filp->private_data; |
3374 | struct trace_array *tr = m->private; | |
7bcfaf54 | 3375 | char buf[64]; |
613f04a0 | 3376 | int ret; |
7bcfaf54 SR |
3377 | |
3378 | if (cnt >= sizeof(buf)) | |
3379 | return -EINVAL; | |
3380 | ||
3381 | if (copy_from_user(&buf, ubuf, cnt)) | |
3382 | return -EFAULT; | |
3383 | ||
a8dd2176 SR |
3384 | buf[cnt] = 0; |
3385 | ||
2b6080f2 | 3386 | ret = trace_set_options(tr, buf); |
613f04a0 SRRH |
3387 | if (ret < 0) |
3388 | return ret; | |
7bcfaf54 | 3389 | |
cf8517cf | 3390 | *ppos += cnt; |
bc0c38d1 SR |
3391 | |
3392 | return cnt; | |
3393 | } | |
3394 | ||
fdb372ed LZ |
3395 | static int tracing_trace_options_open(struct inode *inode, struct file *file) |
3396 | { | |
3397 | if (tracing_disabled) | |
3398 | return -ENODEV; | |
2b6080f2 SR |
3399 | |
3400 | return single_open(file, tracing_trace_options_show, inode->i_private); | |
fdb372ed LZ |
3401 | } |
3402 | ||
5e2336a0 | 3403 | static const struct file_operations tracing_iter_fops = { |
fdb372ed LZ |
3404 | .open = tracing_trace_options_open, |
3405 | .read = seq_read, | |
3406 | .llseek = seq_lseek, | |
3407 | .release = single_release, | |
ee6bce52 | 3408 | .write = tracing_trace_options_write, |
bc0c38d1 SR |
3409 | }; |
3410 | ||
7bd2f24c IM |
3411 | static const char readme_msg[] = |
3412 | "tracing mini-HOWTO:\n\n" | |
22f45649 SRRH |
3413 | "# echo 0 > tracing_on : quick way to disable tracing\n" |
3414 | "# echo 1 > tracing_on : quick way to re-enable tracing\n\n" | |
3415 | " Important files:\n" | |
3416 | " trace\t\t\t- The static contents of the buffer\n" | |
3417 | "\t\t\t To clear the buffer write into this file: echo > trace\n" | |
3418 | " trace_pipe\t\t- A consuming read to see the contents of the buffer\n" | |
3419 | " current_tracer\t- function and latency tracers\n" | |
3420 | " available_tracers\t- list of configured tracers for current_tracer\n" | |
3421 | " buffer_size_kb\t- view and modify size of per cpu buffer\n" | |
3422 | " buffer_total_size_kb - view total size of all cpu buffers\n\n" | |
3423 | " trace_clock\t\t-change the clock used to order events\n" | |
3424 | " local: Per cpu clock but may not be synced across CPUs\n" | |
3425 | " global: Synced across CPUs but slows tracing down.\n" | |
3426 | " counter: Not a clock, but just an increment\n" | |
3427 | " uptime: Jiffy counter from time of boot\n" | |
3428 | " perf: Same clock that perf events use\n" | |
3429 | #ifdef CONFIG_X86_64 | |
3430 | " x86-tsc: TSC cycle counter\n" | |
3431 | #endif | |
3432 | "\n trace_marker\t\t- Writes into this file writes into the kernel buffer\n" | |
3433 | " tracing_cpumask\t- Limit which CPUs to trace\n" | |
3434 | " instances\t\t- Make sub-buffers with: mkdir instances/foo\n" | |
3435 | "\t\t\t Remove sub-buffer with rmdir\n" | |
3436 | " trace_options\t\t- Set format or modify how tracing happens\n" | |
3437 | "\t\t\t Disable an option by adding a suffix 'no' to the option name\n" | |
3438 | #ifdef CONFIG_DYNAMIC_FTRACE | |
3439 | "\n available_filter_functions - list of functions that can be filtered on\n" | |
3440 | " set_ftrace_filter\t- echo function name in here to only trace these functions\n" | |
3441 | " accepts: func_full_name, *func_end, func_begin*, *func_middle*\n" | |
3442 | " modules: Can select a group via module\n" | |
3443 | " Format: :mod:<module-name>\n" | |
3444 | " example: echo :mod:ext3 > set_ftrace_filter\n" | |
3445 | " triggers: a command to perform when function is hit\n" | |
3446 | " Format: <function>:<trigger>[:count]\n" | |
3447 | " trigger: traceon, traceoff\n" | |
3448 | " enable_event:<system>:<event>\n" | |
3449 | " disable_event:<system>:<event>\n" | |
3450 | #ifdef CONFIG_STACKTRACE | |
3451 | " stacktrace\n" | |
3452 | #endif | |
3453 | #ifdef CONFIG_TRACER_SNAPSHOT | |
3454 | " snapshot\n" | |
3455 | #endif | |
3456 | " example: echo do_fault:traceoff > set_ftrace_filter\n" | |
3457 | " echo do_trap:traceoff:3 > set_ftrace_filter\n" | |
3458 | " The first one will disable tracing every time do_fault is hit\n" | |
3459 | " The second will disable tracing at most 3 times when do_trap is hit\n" | |
3460 | " The first time do trap is hit and it disables tracing, the counter\n" | |
3461 | " will decrement to 2. If tracing is already disabled, the counter\n" | |
3462 | " will not decrement. It only decrements when the trigger did work\n" | |
3463 | " To remove trigger without count:\n" | |
3464 | " echo '!<function>:<trigger> > set_ftrace_filter\n" | |
3465 | " To remove trigger with a count:\n" | |
3466 | " echo '!<function>:<trigger>:0 > set_ftrace_filter\n" | |
3467 | " set_ftrace_notrace\t- echo function name in here to never trace.\n" | |
3468 | " accepts: func_full_name, *func_end, func_begin*, *func_middle*\n" | |
3469 | " modules: Can select a group via module command :mod:\n" | |
3470 | " Does not accept triggers\n" | |
3471 | #endif /* CONFIG_DYNAMIC_FTRACE */ | |
3472 | #ifdef CONFIG_FUNCTION_TRACER | |
3473 | " set_ftrace_pid\t- Write pid(s) to only function trace those pids (function)\n" | |
3474 | #endif | |
3475 | #ifdef CONFIG_FUNCTION_GRAPH_TRACER | |
3476 | " set_graph_function\t- Trace the nested calls of a function (function_graph)\n" | |
3477 | " max_graph_depth\t- Trace a limited depth of nested calls (0 is unlimited)\n" | |
3478 | #endif | |
3479 | #ifdef CONFIG_TRACER_SNAPSHOT | |
3480 | "\n snapshot\t\t- Like 'trace' but shows the content of the static snapshot buffer\n" | |
3481 | "\t\t\t Read the contents for more information\n" | |
3482 | #endif | |
3483 | #ifdef CONFIG_STACKTRACE | |
3484 | " stack_trace\t\t- Shows the max stack trace when active\n" | |
3485 | " stack_max_size\t- Shows current max stack size that was traced\n" | |
3486 | "\t\t\t Write into this file to reset the max size (trigger a new trace)\n" | |
3487 | #ifdef CONFIG_DYNAMIC_FTRACE | |
3488 | " stack_trace_filter\t- Like set_ftrace_filter but limits what stack_trace traces\n" | |
3489 | #endif | |
3490 | #endif /* CONFIG_STACKTRACE */ | |
7bd2f24c IM |
3491 | ; |
3492 | ||
3493 | static ssize_t | |
3494 | tracing_readme_read(struct file *filp, char __user *ubuf, | |
3495 | size_t cnt, loff_t *ppos) | |
3496 | { | |
3497 | return simple_read_from_buffer(ubuf, cnt, ppos, | |
3498 | readme_msg, strlen(readme_msg)); | |
3499 | } | |
3500 | ||
5e2336a0 | 3501 | static const struct file_operations tracing_readme_fops = { |
c7078de1 IM |
3502 | .open = tracing_open_generic, |
3503 | .read = tracing_readme_read, | |
b444786f | 3504 | .llseek = generic_file_llseek, |
7bd2f24c IM |
3505 | }; |
3506 | ||
69abe6a5 AP |
3507 | static ssize_t |
3508 | tracing_saved_cmdlines_read(struct file *file, char __user *ubuf, | |
3509 | size_t cnt, loff_t *ppos) | |
3510 | { | |
3511 | char *buf_comm; | |
3512 | char *file_buf; | |
3513 | char *buf; | |
3514 | int len = 0; | |
3515 | int pid; | |
3516 | int i; | |
3517 | ||
3518 | file_buf = kmalloc(SAVED_CMDLINES*(16+TASK_COMM_LEN), GFP_KERNEL); | |
3519 | if (!file_buf) | |
3520 | return -ENOMEM; | |
3521 | ||
3522 | buf_comm = kmalloc(TASK_COMM_LEN, GFP_KERNEL); | |
3523 | if (!buf_comm) { | |
3524 | kfree(file_buf); | |
3525 | return -ENOMEM; | |
3526 | } | |
3527 | ||
3528 | buf = file_buf; | |
3529 | ||
3530 | for (i = 0; i < SAVED_CMDLINES; i++) { | |
3531 | int r; | |
3532 | ||
3533 | pid = map_cmdline_to_pid[i]; | |
3534 | if (pid == -1 || pid == NO_CMDLINE_MAP) | |
3535 | continue; | |
3536 | ||
3537 | trace_find_cmdline(pid, buf_comm); | |
3538 | r = sprintf(buf, "%d %s\n", pid, buf_comm); | |
3539 | buf += r; | |
3540 | len += r; | |
3541 | } | |
3542 | ||
3543 | len = simple_read_from_buffer(ubuf, cnt, ppos, | |
3544 | file_buf, len); | |
3545 | ||
3546 | kfree(file_buf); | |
3547 | kfree(buf_comm); | |
3548 | ||
3549 | return len; | |
3550 | } | |
3551 | ||
3552 | static const struct file_operations tracing_saved_cmdlines_fops = { | |
3553 | .open = tracing_open_generic, | |
3554 | .read = tracing_saved_cmdlines_read, | |
b444786f | 3555 | .llseek = generic_file_llseek, |
69abe6a5 AP |
3556 | }; |
3557 | ||
bc0c38d1 SR |
3558 | static ssize_t |
3559 | tracing_set_trace_read(struct file *filp, char __user *ubuf, | |
3560 | size_t cnt, loff_t *ppos) | |
3561 | { | |
2b6080f2 | 3562 | struct trace_array *tr = filp->private_data; |
ee6c2c1b | 3563 | char buf[MAX_TRACER_SIZE+2]; |
bc0c38d1 SR |
3564 | int r; |
3565 | ||
3566 | mutex_lock(&trace_types_lock); | |
2b6080f2 | 3567 | r = sprintf(buf, "%s\n", tr->current_trace->name); |
bc0c38d1 SR |
3568 | mutex_unlock(&trace_types_lock); |
3569 | ||
4bf39a94 | 3570 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, r); |
bc0c38d1 SR |
3571 | } |
3572 | ||
b6f11df2 ACM |
3573 | int tracer_init(struct tracer *t, struct trace_array *tr) |
3574 | { | |
12883efb | 3575 | tracing_reset_online_cpus(&tr->trace_buffer); |
b6f11df2 ACM |
3576 | return t->init(tr); |
3577 | } | |
3578 | ||
12883efb | 3579 | static void set_buffer_entries(struct trace_buffer *buf, unsigned long val) |
438ced17 VN |
3580 | { |
3581 | int cpu; | |
737223fb | 3582 | |
438ced17 | 3583 | for_each_tracing_cpu(cpu) |
12883efb | 3584 | per_cpu_ptr(buf->data, cpu)->entries = val; |
438ced17 VN |
3585 | } |
3586 | ||
12883efb | 3587 | #ifdef CONFIG_TRACER_MAX_TRACE |
d60da506 | 3588 | /* resize @tr's buffer to the size of @size_tr's entries */ |
12883efb SRRH |
3589 | static int resize_buffer_duplicate_size(struct trace_buffer *trace_buf, |
3590 | struct trace_buffer *size_buf, int cpu_id) | |
d60da506 HT |
3591 | { |
3592 | int cpu, ret = 0; | |
3593 | ||
3594 | if (cpu_id == RING_BUFFER_ALL_CPUS) { | |
3595 | for_each_tracing_cpu(cpu) { | |
12883efb SRRH |
3596 | ret = ring_buffer_resize(trace_buf->buffer, |
3597 | per_cpu_ptr(size_buf->data, cpu)->entries, cpu); | |
d60da506 HT |
3598 | if (ret < 0) |
3599 | break; | |
12883efb SRRH |
3600 | per_cpu_ptr(trace_buf->data, cpu)->entries = |
3601 | per_cpu_ptr(size_buf->data, cpu)->entries; | |
d60da506 HT |
3602 | } |
3603 | } else { | |
12883efb SRRH |
3604 | ret = ring_buffer_resize(trace_buf->buffer, |
3605 | per_cpu_ptr(size_buf->data, cpu_id)->entries, cpu_id); | |
d60da506 | 3606 | if (ret == 0) |
12883efb SRRH |
3607 | per_cpu_ptr(trace_buf->data, cpu_id)->entries = |
3608 | per_cpu_ptr(size_buf->data, cpu_id)->entries; | |
d60da506 HT |
3609 | } |
3610 | ||
3611 | return ret; | |
3612 | } | |
12883efb | 3613 | #endif /* CONFIG_TRACER_MAX_TRACE */ |
d60da506 | 3614 | |
2b6080f2 SR |
3615 | static int __tracing_resize_ring_buffer(struct trace_array *tr, |
3616 | unsigned long size, int cpu) | |
73c5162a SR |
3617 | { |
3618 | int ret; | |
3619 | ||
3620 | /* | |
3621 | * If kernel or user changes the size of the ring buffer | |
a123c52b SR |
3622 | * we use the size that was given, and we can forget about |
3623 | * expanding it later. | |
73c5162a | 3624 | */ |
55034cd6 | 3625 | ring_buffer_expanded = true; |
73c5162a | 3626 | |
b382ede6 | 3627 | /* May be called before buffers are initialized */ |
12883efb | 3628 | if (!tr->trace_buffer.buffer) |
b382ede6 SR |
3629 | return 0; |
3630 | ||
12883efb | 3631 | ret = ring_buffer_resize(tr->trace_buffer.buffer, size, cpu); |
73c5162a SR |
3632 | if (ret < 0) |
3633 | return ret; | |
3634 | ||
12883efb | 3635 | #ifdef CONFIG_TRACER_MAX_TRACE |
2b6080f2 SR |
3636 | if (!(tr->flags & TRACE_ARRAY_FL_GLOBAL) || |
3637 | !tr->current_trace->use_max_tr) | |
ef710e10 KM |
3638 | goto out; |
3639 | ||
12883efb | 3640 | ret = ring_buffer_resize(tr->max_buffer.buffer, size, cpu); |
73c5162a | 3641 | if (ret < 0) { |
12883efb SRRH |
3642 | int r = resize_buffer_duplicate_size(&tr->trace_buffer, |
3643 | &tr->trace_buffer, cpu); | |
73c5162a | 3644 | if (r < 0) { |
a123c52b SR |
3645 | /* |
3646 | * AARGH! We are left with different | |
3647 | * size max buffer!!!! | |
3648 | * The max buffer is our "snapshot" buffer. | |
3649 | * When a tracer needs a snapshot (one of the | |
3650 | * latency tracers), it swaps the max buffer | |
3651 | * with the saved snap shot. We succeeded to | |
3652 | * update the size of the main buffer, but failed to | |
3653 | * update the size of the max buffer. But when we tried | |
3654 | * to reset the main buffer to the original size, we | |
3655 | * failed there too. This is very unlikely to | |
3656 | * happen, but if it does, warn and kill all | |
3657 | * tracing. | |
3658 | */ | |
73c5162a SR |
3659 | WARN_ON(1); |
3660 | tracing_disabled = 1; | |
3661 | } | |
3662 | return ret; | |
3663 | } | |
3664 | ||
438ced17 | 3665 | if (cpu == RING_BUFFER_ALL_CPUS) |
12883efb | 3666 | set_buffer_entries(&tr->max_buffer, size); |
438ced17 | 3667 | else |
12883efb | 3668 | per_cpu_ptr(tr->max_buffer.data, cpu)->entries = size; |
438ced17 | 3669 | |
ef710e10 | 3670 | out: |
12883efb SRRH |
3671 | #endif /* CONFIG_TRACER_MAX_TRACE */ |
3672 | ||
438ced17 | 3673 | if (cpu == RING_BUFFER_ALL_CPUS) |
12883efb | 3674 | set_buffer_entries(&tr->trace_buffer, size); |
438ced17 | 3675 | else |
12883efb | 3676 | per_cpu_ptr(tr->trace_buffer.data, cpu)->entries = size; |
73c5162a SR |
3677 | |
3678 | return ret; | |
3679 | } | |
3680 | ||
2b6080f2 SR |
3681 | static ssize_t tracing_resize_ring_buffer(struct trace_array *tr, |
3682 | unsigned long size, int cpu_id) | |
4f271a2a | 3683 | { |
83f40318 | 3684 | int ret = size; |
4f271a2a VN |
3685 | |
3686 | mutex_lock(&trace_types_lock); | |
3687 | ||
438ced17 VN |
3688 | if (cpu_id != RING_BUFFER_ALL_CPUS) { |
3689 | /* make sure, this cpu is enabled in the mask */ | |
3690 | if (!cpumask_test_cpu(cpu_id, tracing_buffer_mask)) { | |
3691 | ret = -EINVAL; | |
3692 | goto out; | |
3693 | } | |
3694 | } | |
4f271a2a | 3695 | |
2b6080f2 | 3696 | ret = __tracing_resize_ring_buffer(tr, size, cpu_id); |
4f271a2a VN |
3697 | if (ret < 0) |
3698 | ret = -ENOMEM; | |
3699 | ||
438ced17 | 3700 | out: |
4f271a2a VN |
3701 | mutex_unlock(&trace_types_lock); |
3702 | ||
3703 | return ret; | |
3704 | } | |
3705 | ||
ef710e10 | 3706 | |
1852fcce SR |
3707 | /** |
3708 | * tracing_update_buffers - used by tracing facility to expand ring buffers | |
3709 | * | |
3710 | * To save on memory when the tracing is never used on a system with it | |
3711 | * configured in. The ring buffers are set to a minimum size. But once | |
3712 | * a user starts to use the tracing facility, then they need to grow | |
3713 | * to their default size. | |
3714 | * | |
3715 | * This function is to be called when a tracer is about to be used. | |
3716 | */ | |
3717 | int tracing_update_buffers(void) | |
3718 | { | |
3719 | int ret = 0; | |
3720 | ||
1027fcb2 | 3721 | mutex_lock(&trace_types_lock); |
1852fcce | 3722 | if (!ring_buffer_expanded) |
2b6080f2 | 3723 | ret = __tracing_resize_ring_buffer(&global_trace, trace_buf_size, |
438ced17 | 3724 | RING_BUFFER_ALL_CPUS); |
1027fcb2 | 3725 | mutex_unlock(&trace_types_lock); |
1852fcce SR |
3726 | |
3727 | return ret; | |
3728 | } | |
3729 | ||
577b785f SR |
3730 | struct trace_option_dentry; |
3731 | ||
3732 | static struct trace_option_dentry * | |
2b6080f2 | 3733 | create_trace_option_files(struct trace_array *tr, struct tracer *tracer); |
577b785f SR |
3734 | |
3735 | static void | |
3736 | destroy_trace_option_files(struct trace_option_dentry *topts); | |
3737 | ||
b2821ae6 | 3738 | static int tracing_set_tracer(const char *buf) |
bc0c38d1 | 3739 | { |
577b785f | 3740 | static struct trace_option_dentry *topts; |
bc0c38d1 SR |
3741 | struct trace_array *tr = &global_trace; |
3742 | struct tracer *t; | |
12883efb | 3743 | #ifdef CONFIG_TRACER_MAX_TRACE |
34600f0e | 3744 | bool had_max_tr; |
12883efb | 3745 | #endif |
d9e54076 | 3746 | int ret = 0; |
bc0c38d1 | 3747 | |
1027fcb2 SR |
3748 | mutex_lock(&trace_types_lock); |
3749 | ||
73c5162a | 3750 | if (!ring_buffer_expanded) { |
2b6080f2 | 3751 | ret = __tracing_resize_ring_buffer(tr, trace_buf_size, |
438ced17 | 3752 | RING_BUFFER_ALL_CPUS); |
73c5162a | 3753 | if (ret < 0) |
59f586db | 3754 | goto out; |
73c5162a SR |
3755 | ret = 0; |
3756 | } | |
3757 | ||
bc0c38d1 SR |
3758 | for (t = trace_types; t; t = t->next) { |
3759 | if (strcmp(t->name, buf) == 0) | |
3760 | break; | |
3761 | } | |
c2931e05 FW |
3762 | if (!t) { |
3763 | ret = -EINVAL; | |
3764 | goto out; | |
3765 | } | |
2b6080f2 | 3766 | if (t == tr->current_trace) |
bc0c38d1 SR |
3767 | goto out; |
3768 | ||
9f029e83 | 3769 | trace_branch_disable(); |
613f04a0 | 3770 | |
2b6080f2 | 3771 | tr->current_trace->enabled = false; |
613f04a0 | 3772 | |
2b6080f2 SR |
3773 | if (tr->current_trace->reset) |
3774 | tr->current_trace->reset(tr); | |
34600f0e | 3775 | |
12883efb | 3776 | /* Current trace needs to be nop_trace before synchronize_sched */ |
2b6080f2 | 3777 | tr->current_trace = &nop_trace; |
34600f0e | 3778 | |
45ad21ca SRRH |
3779 | #ifdef CONFIG_TRACER_MAX_TRACE |
3780 | had_max_tr = tr->allocated_snapshot; | |
34600f0e SR |
3781 | |
3782 | if (had_max_tr && !t->use_max_tr) { | |
3783 | /* | |
3784 | * We need to make sure that the update_max_tr sees that | |
3785 | * current_trace changed to nop_trace to keep it from | |
3786 | * swapping the buffers after we resize it. | |
3787 | * The update_max_tr is called from interrupts disabled | |
3788 | * so a synchronized_sched() is sufficient. | |
3789 | */ | |
3790 | synchronize_sched(); | |
3209cff4 | 3791 | free_snapshot(tr); |
ef710e10 | 3792 | } |
12883efb | 3793 | #endif |
577b785f SR |
3794 | destroy_trace_option_files(topts); |
3795 | ||
2b6080f2 | 3796 | topts = create_trace_option_files(tr, t); |
12883efb SRRH |
3797 | |
3798 | #ifdef CONFIG_TRACER_MAX_TRACE | |
34600f0e | 3799 | if (t->use_max_tr && !had_max_tr) { |
3209cff4 | 3800 | ret = alloc_snapshot(tr); |
d60da506 HT |
3801 | if (ret < 0) |
3802 | goto out; | |
ef710e10 | 3803 | } |
12883efb | 3804 | #endif |
577b785f | 3805 | |
1c80025a | 3806 | if (t->init) { |
b6f11df2 | 3807 | ret = tracer_init(t, tr); |
1c80025a FW |
3808 | if (ret) |
3809 | goto out; | |
3810 | } | |
bc0c38d1 | 3811 | |
2b6080f2 SR |
3812 | tr->current_trace = t; |
3813 | tr->current_trace->enabled = true; | |
9f029e83 | 3814 | trace_branch_enable(tr); |
bc0c38d1 SR |
3815 | out: |
3816 | mutex_unlock(&trace_types_lock); | |
3817 | ||
d9e54076 PZ |
3818 | return ret; |
3819 | } | |
3820 | ||
3821 | static ssize_t | |
3822 | tracing_set_trace_write(struct file *filp, const char __user *ubuf, | |
3823 | size_t cnt, loff_t *ppos) | |
3824 | { | |
ee6c2c1b | 3825 | char buf[MAX_TRACER_SIZE+1]; |
d9e54076 PZ |
3826 | int i; |
3827 | size_t ret; | |
e6e7a65a FW |
3828 | int err; |
3829 | ||
3830 | ret = cnt; | |
d9e54076 | 3831 | |
ee6c2c1b LZ |
3832 | if (cnt > MAX_TRACER_SIZE) |
3833 | cnt = MAX_TRACER_SIZE; | |
d9e54076 PZ |
3834 | |
3835 | if (copy_from_user(&buf, ubuf, cnt)) | |
3836 | return -EFAULT; | |
3837 | ||
3838 | buf[cnt] = 0; | |
3839 | ||
3840 | /* strip ending whitespace. */ | |
3841 | for (i = cnt - 1; i > 0 && isspace(buf[i]); i--) | |
3842 | buf[i] = 0; | |
3843 | ||
e6e7a65a FW |
3844 | err = tracing_set_tracer(buf); |
3845 | if (err) | |
3846 | return err; | |
d9e54076 | 3847 | |
cf8517cf | 3848 | *ppos += ret; |
bc0c38d1 | 3849 | |
c2931e05 | 3850 | return ret; |
bc0c38d1 SR |
3851 | } |
3852 | ||
3853 | static ssize_t | |
3854 | tracing_max_lat_read(struct file *filp, char __user *ubuf, | |
3855 | size_t cnt, loff_t *ppos) | |
3856 | { | |
3857 | unsigned long *ptr = filp->private_data; | |
3858 | char buf[64]; | |
3859 | int r; | |
3860 | ||
cffae437 | 3861 | r = snprintf(buf, sizeof(buf), "%ld\n", |
bc0c38d1 | 3862 | *ptr == (unsigned long)-1 ? -1 : nsecs_to_usecs(*ptr)); |
cffae437 SR |
3863 | if (r > sizeof(buf)) |
3864 | r = sizeof(buf); | |
4bf39a94 | 3865 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, r); |
bc0c38d1 SR |
3866 | } |
3867 | ||
3868 | static ssize_t | |
3869 | tracing_max_lat_write(struct file *filp, const char __user *ubuf, | |
3870 | size_t cnt, loff_t *ppos) | |
3871 | { | |
5e39841c | 3872 | unsigned long *ptr = filp->private_data; |
5e39841c | 3873 | unsigned long val; |
c6caeeb1 | 3874 | int ret; |
bc0c38d1 | 3875 | |
22fe9b54 PH |
3876 | ret = kstrtoul_from_user(ubuf, cnt, 10, &val); |
3877 | if (ret) | |
c6caeeb1 | 3878 | return ret; |
bc0c38d1 SR |
3879 | |
3880 | *ptr = val * 1000; | |
3881 | ||
3882 | return cnt; | |
3883 | } | |
3884 | ||
b3806b43 SR |
3885 | static int tracing_open_pipe(struct inode *inode, struct file *filp) |
3886 | { | |
2b6080f2 SR |
3887 | struct trace_cpu *tc = inode->i_private; |
3888 | struct trace_array *tr = tc->tr; | |
b3806b43 | 3889 | struct trace_iterator *iter; |
b04cc6b1 | 3890 | int ret = 0; |
b3806b43 SR |
3891 | |
3892 | if (tracing_disabled) | |
3893 | return -ENODEV; | |
3894 | ||
b04cc6b1 FW |
3895 | mutex_lock(&trace_types_lock); |
3896 | ||
b3806b43 SR |
3897 | /* create a buffer to store the information to pass to userspace */ |
3898 | iter = kzalloc(sizeof(*iter), GFP_KERNEL); | |
b04cc6b1 FW |
3899 | if (!iter) { |
3900 | ret = -ENOMEM; | |
3901 | goto out; | |
3902 | } | |
b3806b43 | 3903 | |
d7350c3f FW |
3904 | /* |
3905 | * We make a copy of the current tracer to avoid concurrent | |
3906 | * changes on it while we are reading. | |
3907 | */ | |
3908 | iter->trace = kmalloc(sizeof(*iter->trace), GFP_KERNEL); | |
3909 | if (!iter->trace) { | |
3910 | ret = -ENOMEM; | |
3911 | goto fail; | |
3912 | } | |
2b6080f2 | 3913 | *iter->trace = *tr->current_trace; |
d7350c3f | 3914 | |
4462344e | 3915 | if (!alloc_cpumask_var(&iter->started, GFP_KERNEL)) { |
b04cc6b1 | 3916 | ret = -ENOMEM; |
d7350c3f | 3917 | goto fail; |
4462344e RR |
3918 | } |
3919 | ||
a309720c | 3920 | /* trace pipe does not show start of buffer */ |
4462344e | 3921 | cpumask_setall(iter->started); |
a309720c | 3922 | |
112f38a7 SR |
3923 | if (trace_flags & TRACE_ITER_LATENCY_FMT) |
3924 | iter->iter_flags |= TRACE_FILE_LAT_FMT; | |
3925 | ||
8be0709f DS |
3926 | /* Output in nanoseconds only if we are using a clock in nanoseconds. */ |
3927 | if (trace_clocks[trace_clock_id].in_ns) | |
3928 | iter->iter_flags |= TRACE_FILE_TIME_IN_NS; | |
3929 | ||
2b6080f2 SR |
3930 | iter->cpu_file = tc->cpu; |
3931 | iter->tr = tc->tr; | |
12883efb | 3932 | iter->trace_buffer = &tc->tr->trace_buffer; |
d7350c3f | 3933 | mutex_init(&iter->mutex); |
b3806b43 SR |
3934 | filp->private_data = iter; |
3935 | ||
107bad8b SR |
3936 | if (iter->trace->pipe_open) |
3937 | iter->trace->pipe_open(iter); | |
107bad8b | 3938 | |
b444786f | 3939 | nonseekable_open(inode, filp); |
b04cc6b1 FW |
3940 | out: |
3941 | mutex_unlock(&trace_types_lock); | |
3942 | return ret; | |
d7350c3f FW |
3943 | |
3944 | fail: | |
3945 | kfree(iter->trace); | |
3946 | kfree(iter); | |
3947 | mutex_unlock(&trace_types_lock); | |
3948 | return ret; | |
b3806b43 SR |
3949 | } |
3950 | ||
3951 | static int tracing_release_pipe(struct inode *inode, struct file *file) | |
3952 | { | |
3953 | struct trace_iterator *iter = file->private_data; | |
3954 | ||
b04cc6b1 FW |
3955 | mutex_lock(&trace_types_lock); |
3956 | ||
29bf4a5e | 3957 | if (iter->trace->pipe_close) |
c521efd1 SR |
3958 | iter->trace->pipe_close(iter); |
3959 | ||
b04cc6b1 FW |
3960 | mutex_unlock(&trace_types_lock); |
3961 | ||
4462344e | 3962 | free_cpumask_var(iter->started); |
d7350c3f FW |
3963 | mutex_destroy(&iter->mutex); |
3964 | kfree(iter->trace); | |
b3806b43 | 3965 | kfree(iter); |
b3806b43 SR |
3966 | |
3967 | return 0; | |
3968 | } | |
3969 | ||
2a2cc8f7 | 3970 | static unsigned int |
cc60cdc9 | 3971 | trace_poll(struct trace_iterator *iter, struct file *filp, poll_table *poll_table) |
2a2cc8f7 | 3972 | { |
15693458 SRRH |
3973 | /* Iterators are static, they should be filled or empty */ |
3974 | if (trace_buffer_iter(iter, iter->cpu_file)) | |
3975 | return POLLIN | POLLRDNORM; | |
2a2cc8f7 | 3976 | |
15693458 | 3977 | if (trace_flags & TRACE_ITER_BLOCK) |
2a2cc8f7 SSP |
3978 | /* |
3979 | * Always select as readable when in blocking mode | |
3980 | */ | |
3981 | return POLLIN | POLLRDNORM; | |
15693458 | 3982 | else |
12883efb | 3983 | return ring_buffer_poll_wait(iter->trace_buffer->buffer, iter->cpu_file, |
15693458 | 3984 | filp, poll_table); |
2a2cc8f7 | 3985 | } |
2a2cc8f7 | 3986 | |
cc60cdc9 SR |
3987 | static unsigned int |
3988 | tracing_poll_pipe(struct file *filp, poll_table *poll_table) | |
3989 | { | |
3990 | struct trace_iterator *iter = filp->private_data; | |
3991 | ||
3992 | return trace_poll(iter, filp, poll_table); | |
2a2cc8f7 SSP |
3993 | } |
3994 | ||
6eaaa5d5 FW |
3995 | /* |
3996 | * This is a make-shift waitqueue. | |
3997 | * A tracer might use this callback on some rare cases: | |
3998 | * | |
3999 | * 1) the current tracer might hold the runqueue lock when it wakes up | |
4000 | * a reader, hence a deadlock (sched, function, and function graph tracers) | |
4001 | * 2) the function tracers, trace all functions, we don't want | |
4002 | * the overhead of calling wake_up and friends | |
4003 | * (and tracing them too) | |
4004 | * | |
4005 | * Anyway, this is really very primitive wakeup. | |
4006 | */ | |
4007 | void poll_wait_pipe(struct trace_iterator *iter) | |
4008 | { | |
4009 | set_current_state(TASK_INTERRUPTIBLE); | |
4010 | /* sleep for 100 msecs, and try again. */ | |
4011 | schedule_timeout(HZ / 10); | |
4012 | } | |
4013 | ||
ff98781b EGM |
4014 | /* Must be called with trace_types_lock mutex held. */ |
4015 | static int tracing_wait_pipe(struct file *filp) | |
b3806b43 SR |
4016 | { |
4017 | struct trace_iterator *iter = filp->private_data; | |
b3806b43 | 4018 | |
b3806b43 | 4019 | while (trace_empty(iter)) { |
2dc8f095 | 4020 | |
107bad8b | 4021 | if ((filp->f_flags & O_NONBLOCK)) { |
ff98781b | 4022 | return -EAGAIN; |
107bad8b | 4023 | } |
2dc8f095 | 4024 | |
d7350c3f | 4025 | mutex_unlock(&iter->mutex); |
107bad8b | 4026 | |
6eaaa5d5 | 4027 | iter->trace->wait_pipe(iter); |
b3806b43 | 4028 | |
d7350c3f | 4029 | mutex_lock(&iter->mutex); |
107bad8b | 4030 | |
6eaaa5d5 | 4031 | if (signal_pending(current)) |
ff98781b | 4032 | return -EINTR; |
b3806b43 SR |
4033 | |
4034 | /* | |
250bfd3d | 4035 | * We block until we read something and tracing is disabled. |
b3806b43 SR |
4036 | * We still block if tracing is disabled, but we have never |
4037 | * read anything. This allows a user to cat this file, and | |
4038 | * then enable tracing. But after we have read something, | |
4039 | * we give an EOF when tracing is again disabled. | |
4040 | * | |
4041 | * iter->pos will be 0 if we haven't read anything. | |
4042 | */ | |
10246fa3 | 4043 | if (!tracing_is_on() && iter->pos) |
b3806b43 | 4044 | break; |
b3806b43 SR |
4045 | } |
4046 | ||
ff98781b EGM |
4047 | return 1; |
4048 | } | |
4049 | ||
4050 | /* | |
4051 | * Consumer reader. | |
4052 | */ | |
4053 | static ssize_t | |
4054 | tracing_read_pipe(struct file *filp, char __user *ubuf, | |
4055 | size_t cnt, loff_t *ppos) | |
4056 | { | |
4057 | struct trace_iterator *iter = filp->private_data; | |
2b6080f2 | 4058 | struct trace_array *tr = iter->tr; |
ff98781b EGM |
4059 | ssize_t sret; |
4060 | ||
4061 | /* return any leftover data */ | |
4062 | sret = trace_seq_to_user(&iter->seq, ubuf, cnt); | |
4063 | if (sret != -EBUSY) | |
4064 | return sret; | |
4065 | ||
f9520750 | 4066 | trace_seq_init(&iter->seq); |
ff98781b | 4067 | |
d7350c3f | 4068 | /* copy the tracer to avoid using a global lock all around */ |
ff98781b | 4069 | mutex_lock(&trace_types_lock); |
2b6080f2 SR |
4070 | if (unlikely(iter->trace->name != tr->current_trace->name)) |
4071 | *iter->trace = *tr->current_trace; | |
d7350c3f FW |
4072 | mutex_unlock(&trace_types_lock); |
4073 | ||
4074 | /* | |
4075 | * Avoid more than one consumer on a single file descriptor | |
4076 | * This is just a matter of traces coherency, the ring buffer itself | |
4077 | * is protected. | |
4078 | */ | |
4079 | mutex_lock(&iter->mutex); | |
ff98781b EGM |
4080 | if (iter->trace->read) { |
4081 | sret = iter->trace->read(iter, filp, ubuf, cnt, ppos); | |
4082 | if (sret) | |
4083 | goto out; | |
4084 | } | |
4085 | ||
4086 | waitagain: | |
4087 | sret = tracing_wait_pipe(filp); | |
4088 | if (sret <= 0) | |
4089 | goto out; | |
4090 | ||
b3806b43 | 4091 | /* stop when tracing is finished */ |
ff98781b EGM |
4092 | if (trace_empty(iter)) { |
4093 | sret = 0; | |
107bad8b | 4094 | goto out; |
ff98781b | 4095 | } |
b3806b43 SR |
4096 | |
4097 | if (cnt >= PAGE_SIZE) | |
4098 | cnt = PAGE_SIZE - 1; | |
4099 | ||
53d0aa77 | 4100 | /* reset all but tr, trace, and overruns */ |
53d0aa77 SR |
4101 | memset(&iter->seq, 0, |
4102 | sizeof(struct trace_iterator) - | |
4103 | offsetof(struct trace_iterator, seq)); | |
4823ed7e | 4104 | iter->pos = -1; |
b3806b43 | 4105 | |
4f535968 | 4106 | trace_event_read_lock(); |
7e53bd42 | 4107 | trace_access_lock(iter->cpu_file); |
955b61e5 | 4108 | while (trace_find_next_entry_inc(iter) != NULL) { |
2c4f035f | 4109 | enum print_line_t ret; |
088b1e42 SR |
4110 | int len = iter->seq.len; |
4111 | ||
f9896bf3 | 4112 | ret = print_trace_line(iter); |
2c4f035f | 4113 | if (ret == TRACE_TYPE_PARTIAL_LINE) { |
088b1e42 SR |
4114 | /* don't print partial lines */ |
4115 | iter->seq.len = len; | |
b3806b43 | 4116 | break; |
088b1e42 | 4117 | } |
b91facc3 FW |
4118 | if (ret != TRACE_TYPE_NO_CONSUME) |
4119 | trace_consume(iter); | |
b3806b43 SR |
4120 | |
4121 | if (iter->seq.len >= cnt) | |
4122 | break; | |
ee5e51f5 JO |
4123 | |
4124 | /* | |
4125 | * Setting the full flag means we reached the trace_seq buffer | |
4126 | * size and we should leave by partial output condition above. | |
4127 | * One of the trace_seq_* functions is not used properly. | |
4128 | */ | |
4129 | WARN_ONCE(iter->seq.full, "full flag set for trace type %d", | |
4130 | iter->ent->type); | |
b3806b43 | 4131 | } |
7e53bd42 | 4132 | trace_access_unlock(iter->cpu_file); |
4f535968 | 4133 | trace_event_read_unlock(); |
b3806b43 | 4134 | |
b3806b43 | 4135 | /* Now copy what we have to the user */ |
6c6c2796 PP |
4136 | sret = trace_seq_to_user(&iter->seq, ubuf, cnt); |
4137 | if (iter->seq.readpos >= iter->seq.len) | |
f9520750 | 4138 | trace_seq_init(&iter->seq); |
9ff4b974 PP |
4139 | |
4140 | /* | |
25985edc | 4141 | * If there was nothing to send to user, in spite of consuming trace |
9ff4b974 PP |
4142 | * entries, go back to wait for more entries. |
4143 | */ | |
6c6c2796 | 4144 | if (sret == -EBUSY) |
9ff4b974 | 4145 | goto waitagain; |
b3806b43 | 4146 | |
107bad8b | 4147 | out: |
d7350c3f | 4148 | mutex_unlock(&iter->mutex); |
107bad8b | 4149 | |
6c6c2796 | 4150 | return sret; |
b3806b43 SR |
4151 | } |
4152 | ||
3c56819b EGM |
4153 | static void tracing_pipe_buf_release(struct pipe_inode_info *pipe, |
4154 | struct pipe_buffer *buf) | |
4155 | { | |
4156 | __free_page(buf->page); | |
4157 | } | |
4158 | ||
4159 | static void tracing_spd_release_pipe(struct splice_pipe_desc *spd, | |
4160 | unsigned int idx) | |
4161 | { | |
4162 | __free_page(spd->pages[idx]); | |
4163 | } | |
4164 | ||
28dfef8f | 4165 | static const struct pipe_buf_operations tracing_pipe_buf_ops = { |
34cd4998 SR |
4166 | .can_merge = 0, |
4167 | .map = generic_pipe_buf_map, | |
4168 | .unmap = generic_pipe_buf_unmap, | |
4169 | .confirm = generic_pipe_buf_confirm, | |
4170 | .release = tracing_pipe_buf_release, | |
4171 | .steal = generic_pipe_buf_steal, | |
4172 | .get = generic_pipe_buf_get, | |
3c56819b EGM |
4173 | }; |
4174 | ||
34cd4998 | 4175 | static size_t |
fa7c7f6e | 4176 | tracing_fill_pipe_page(size_t rem, struct trace_iterator *iter) |
34cd4998 SR |
4177 | { |
4178 | size_t count; | |
4179 | int ret; | |
4180 | ||
4181 | /* Seq buffer is page-sized, exactly what we need. */ | |
4182 | for (;;) { | |
4183 | count = iter->seq.len; | |
4184 | ret = print_trace_line(iter); | |
4185 | count = iter->seq.len - count; | |
4186 | if (rem < count) { | |
4187 | rem = 0; | |
4188 | iter->seq.len -= count; | |
4189 | break; | |
4190 | } | |
4191 | if (ret == TRACE_TYPE_PARTIAL_LINE) { | |
4192 | iter->seq.len -= count; | |
4193 | break; | |
4194 | } | |
4195 | ||
74e7ff8c LJ |
4196 | if (ret != TRACE_TYPE_NO_CONSUME) |
4197 | trace_consume(iter); | |
34cd4998 | 4198 | rem -= count; |
955b61e5 | 4199 | if (!trace_find_next_entry_inc(iter)) { |
34cd4998 SR |
4200 | rem = 0; |
4201 | iter->ent = NULL; | |
4202 | break; | |
4203 | } | |
4204 | } | |
4205 | ||
4206 | return rem; | |
4207 | } | |
4208 | ||
3c56819b EGM |
4209 | static ssize_t tracing_splice_read_pipe(struct file *filp, |
4210 | loff_t *ppos, | |
4211 | struct pipe_inode_info *pipe, | |
4212 | size_t len, | |
4213 | unsigned int flags) | |
4214 | { | |
35f3d14d JA |
4215 | struct page *pages_def[PIPE_DEF_BUFFERS]; |
4216 | struct partial_page partial_def[PIPE_DEF_BUFFERS]; | |
3c56819b EGM |
4217 | struct trace_iterator *iter = filp->private_data; |
4218 | struct splice_pipe_desc spd = { | |
35f3d14d JA |
4219 | .pages = pages_def, |
4220 | .partial = partial_def, | |
34cd4998 | 4221 | .nr_pages = 0, /* This gets updated below. */ |
047fe360 | 4222 | .nr_pages_max = PIPE_DEF_BUFFERS, |
34cd4998 SR |
4223 | .flags = flags, |
4224 | .ops = &tracing_pipe_buf_ops, | |
4225 | .spd_release = tracing_spd_release_pipe, | |
3c56819b | 4226 | }; |
2b6080f2 | 4227 | struct trace_array *tr = iter->tr; |
3c56819b | 4228 | ssize_t ret; |
34cd4998 | 4229 | size_t rem; |
3c56819b EGM |
4230 | unsigned int i; |
4231 | ||
35f3d14d JA |
4232 | if (splice_grow_spd(pipe, &spd)) |
4233 | return -ENOMEM; | |
4234 | ||
d7350c3f | 4235 | /* copy the tracer to avoid using a global lock all around */ |
3c56819b | 4236 | mutex_lock(&trace_types_lock); |
2b6080f2 SR |
4237 | if (unlikely(iter->trace->name != tr->current_trace->name)) |
4238 | *iter->trace = *tr->current_trace; | |
d7350c3f FW |
4239 | mutex_unlock(&trace_types_lock); |
4240 | ||
4241 | mutex_lock(&iter->mutex); | |
3c56819b EGM |
4242 | |
4243 | if (iter->trace->splice_read) { | |
4244 | ret = iter->trace->splice_read(iter, filp, | |
4245 | ppos, pipe, len, flags); | |
4246 | if (ret) | |
34cd4998 | 4247 | goto out_err; |
3c56819b EGM |
4248 | } |
4249 | ||
4250 | ret = tracing_wait_pipe(filp); | |
4251 | if (ret <= 0) | |
34cd4998 | 4252 | goto out_err; |
3c56819b | 4253 | |
955b61e5 | 4254 | if (!iter->ent && !trace_find_next_entry_inc(iter)) { |
3c56819b | 4255 | ret = -EFAULT; |
34cd4998 | 4256 | goto out_err; |
3c56819b EGM |
4257 | } |
4258 | ||
4f535968 | 4259 | trace_event_read_lock(); |
7e53bd42 | 4260 | trace_access_lock(iter->cpu_file); |
4f535968 | 4261 | |
3c56819b | 4262 | /* Fill as many pages as possible. */ |
35f3d14d JA |
4263 | for (i = 0, rem = len; i < pipe->buffers && rem; i++) { |
4264 | spd.pages[i] = alloc_page(GFP_KERNEL); | |
4265 | if (!spd.pages[i]) | |
34cd4998 | 4266 | break; |
3c56819b | 4267 | |
fa7c7f6e | 4268 | rem = tracing_fill_pipe_page(rem, iter); |
3c56819b EGM |
4269 | |
4270 | /* Copy the data into the page, so we can start over. */ | |
4271 | ret = trace_seq_to_buffer(&iter->seq, | |
35f3d14d | 4272 | page_address(spd.pages[i]), |
3c56819b EGM |
4273 | iter->seq.len); |
4274 | if (ret < 0) { | |
35f3d14d | 4275 | __free_page(spd.pages[i]); |
3c56819b EGM |
4276 | break; |
4277 | } | |
35f3d14d JA |
4278 | spd.partial[i].offset = 0; |
4279 | spd.partial[i].len = iter->seq.len; | |
3c56819b | 4280 | |
f9520750 | 4281 | trace_seq_init(&iter->seq); |
3c56819b EGM |
4282 | } |
4283 | ||
7e53bd42 | 4284 | trace_access_unlock(iter->cpu_file); |
4f535968 | 4285 | trace_event_read_unlock(); |
d7350c3f | 4286 | mutex_unlock(&iter->mutex); |
3c56819b EGM |
4287 | |
4288 | spd.nr_pages = i; | |
4289 | ||
35f3d14d JA |
4290 | ret = splice_to_pipe(pipe, &spd); |
4291 | out: | |
047fe360 | 4292 | splice_shrink_spd(&spd); |
35f3d14d | 4293 | return ret; |
3c56819b | 4294 | |
34cd4998 | 4295 | out_err: |
d7350c3f | 4296 | mutex_unlock(&iter->mutex); |
35f3d14d | 4297 | goto out; |
3c56819b EGM |
4298 | } |
4299 | ||
a98a3c3f SR |
4300 | static ssize_t |
4301 | tracing_entries_read(struct file *filp, char __user *ubuf, | |
4302 | size_t cnt, loff_t *ppos) | |
4303 | { | |
2b6080f2 SR |
4304 | struct trace_cpu *tc = filp->private_data; |
4305 | struct trace_array *tr = tc->tr; | |
438ced17 VN |
4306 | char buf[64]; |
4307 | int r = 0; | |
4308 | ssize_t ret; | |
a98a3c3f | 4309 | |
db526ca3 | 4310 | mutex_lock(&trace_types_lock); |
438ced17 | 4311 | |
2b6080f2 | 4312 | if (tc->cpu == RING_BUFFER_ALL_CPUS) { |
438ced17 VN |
4313 | int cpu, buf_size_same; |
4314 | unsigned long size; | |
4315 | ||
4316 | size = 0; | |
4317 | buf_size_same = 1; | |
4318 | /* check if all cpu sizes are same */ | |
4319 | for_each_tracing_cpu(cpu) { | |
4320 | /* fill in the size from first enabled cpu */ | |
4321 | if (size == 0) | |
12883efb SRRH |
4322 | size = per_cpu_ptr(tr->trace_buffer.data, cpu)->entries; |
4323 | if (size != per_cpu_ptr(tr->trace_buffer.data, cpu)->entries) { | |
438ced17 VN |
4324 | buf_size_same = 0; |
4325 | break; | |
4326 | } | |
4327 | } | |
4328 | ||
4329 | if (buf_size_same) { | |
4330 | if (!ring_buffer_expanded) | |
4331 | r = sprintf(buf, "%lu (expanded: %lu)\n", | |
4332 | size >> 10, | |
4333 | trace_buf_size >> 10); | |
4334 | else | |
4335 | r = sprintf(buf, "%lu\n", size >> 10); | |
4336 | } else | |
4337 | r = sprintf(buf, "X\n"); | |
4338 | } else | |
12883efb | 4339 | r = sprintf(buf, "%lu\n", per_cpu_ptr(tr->trace_buffer.data, tc->cpu)->entries >> 10); |
438ced17 | 4340 | |
db526ca3 SR |
4341 | mutex_unlock(&trace_types_lock); |
4342 | ||
438ced17 VN |
4343 | ret = simple_read_from_buffer(ubuf, cnt, ppos, buf, r); |
4344 | return ret; | |
a98a3c3f SR |
4345 | } |
4346 | ||
4347 | static ssize_t | |
4348 | tracing_entries_write(struct file *filp, const char __user *ubuf, | |
4349 | size_t cnt, loff_t *ppos) | |
4350 | { | |
2b6080f2 | 4351 | struct trace_cpu *tc = filp->private_data; |
a98a3c3f | 4352 | unsigned long val; |
4f271a2a | 4353 | int ret; |
a98a3c3f | 4354 | |
22fe9b54 PH |
4355 | ret = kstrtoul_from_user(ubuf, cnt, 10, &val); |
4356 | if (ret) | |
c6caeeb1 | 4357 | return ret; |
a98a3c3f SR |
4358 | |
4359 | /* must have at least 1 entry */ | |
4360 | if (!val) | |
4361 | return -EINVAL; | |
4362 | ||
1696b2b0 SR |
4363 | /* value is in KB */ |
4364 | val <<= 10; | |
4365 | ||
2b6080f2 | 4366 | ret = tracing_resize_ring_buffer(tc->tr, val, tc->cpu); |
4f271a2a VN |
4367 | if (ret < 0) |
4368 | return ret; | |
a98a3c3f | 4369 | |
cf8517cf | 4370 | *ppos += cnt; |
a98a3c3f | 4371 | |
4f271a2a VN |
4372 | return cnt; |
4373 | } | |
bf5e6519 | 4374 | |
f81ab074 VN |
4375 | static ssize_t |
4376 | tracing_total_entries_read(struct file *filp, char __user *ubuf, | |
4377 | size_t cnt, loff_t *ppos) | |
4378 | { | |
4379 | struct trace_array *tr = filp->private_data; | |
4380 | char buf[64]; | |
4381 | int r, cpu; | |
4382 | unsigned long size = 0, expanded_size = 0; | |
4383 | ||
4384 | mutex_lock(&trace_types_lock); | |
4385 | for_each_tracing_cpu(cpu) { | |
12883efb | 4386 | size += per_cpu_ptr(tr->trace_buffer.data, cpu)->entries >> 10; |
f81ab074 VN |
4387 | if (!ring_buffer_expanded) |
4388 | expanded_size += trace_buf_size >> 10; | |
4389 | } | |
4390 | if (ring_buffer_expanded) | |
4391 | r = sprintf(buf, "%lu\n", size); | |
4392 | else | |
4393 | r = sprintf(buf, "%lu (expanded: %lu)\n", size, expanded_size); | |
4394 | mutex_unlock(&trace_types_lock); | |
4395 | ||
4396 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, r); | |
4397 | } | |
4398 | ||
4f271a2a VN |
4399 | static ssize_t |
4400 | tracing_free_buffer_write(struct file *filp, const char __user *ubuf, | |
4401 | size_t cnt, loff_t *ppos) | |
4402 | { | |
4403 | /* | |
4404 | * There is no need to read what the user has written, this function | |
4405 | * is just to make sure that there is no error when "echo" is used | |
4406 | */ | |
4407 | ||
4408 | *ppos += cnt; | |
a98a3c3f SR |
4409 | |
4410 | return cnt; | |
4411 | } | |
4412 | ||
4f271a2a VN |
4413 | static int |
4414 | tracing_free_buffer_release(struct inode *inode, struct file *filp) | |
4415 | { | |
2b6080f2 SR |
4416 | struct trace_array *tr = inode->i_private; |
4417 | ||
cf30cf67 SR |
4418 | /* disable tracing ? */ |
4419 | if (trace_flags & TRACE_ITER_STOP_ON_FREE) | |
4420 | tracing_off(); | |
4f271a2a | 4421 | /* resize the ring buffer to 0 */ |
2b6080f2 | 4422 | tracing_resize_ring_buffer(tr, 0, RING_BUFFER_ALL_CPUS); |
4f271a2a VN |
4423 | |
4424 | return 0; | |
4425 | } | |
4426 | ||
5bf9a1ee PP |
4427 | static ssize_t |
4428 | tracing_mark_write(struct file *filp, const char __user *ubuf, | |
4429 | size_t cnt, loff_t *fpos) | |
4430 | { | |
d696b58c | 4431 | unsigned long addr = (unsigned long)ubuf; |
2d71619c | 4432 | struct trace_array *tr = filp->private_data; |
d696b58c SR |
4433 | struct ring_buffer_event *event; |
4434 | struct ring_buffer *buffer; | |
4435 | struct print_entry *entry; | |
4436 | unsigned long irq_flags; | |
4437 | struct page *pages[2]; | |
6edb2a8a | 4438 | void *map_page[2]; |
d696b58c SR |
4439 | int nr_pages = 1; |
4440 | ssize_t written; | |
d696b58c SR |
4441 | int offset; |
4442 | int size; | |
4443 | int len; | |
4444 | int ret; | |
6edb2a8a | 4445 | int i; |
5bf9a1ee | 4446 | |
c76f0694 | 4447 | if (tracing_disabled) |
5bf9a1ee PP |
4448 | return -EINVAL; |
4449 | ||
5224c3a3 MSB |
4450 | if (!(trace_flags & TRACE_ITER_MARKERS)) |
4451 | return -EINVAL; | |
4452 | ||
5bf9a1ee PP |
4453 | if (cnt > TRACE_BUF_SIZE) |
4454 | cnt = TRACE_BUF_SIZE; | |
4455 | ||
d696b58c SR |
4456 | /* |
4457 | * Userspace is injecting traces into the kernel trace buffer. | |
4458 | * We want to be as non intrusive as possible. | |
4459 | * To do so, we do not want to allocate any special buffers | |
4460 | * or take any locks, but instead write the userspace data | |
4461 | * straight into the ring buffer. | |
4462 | * | |
4463 | * First we need to pin the userspace buffer into memory, | |
4464 | * which, most likely it is, because it just referenced it. | |
4465 | * But there's no guarantee that it is. By using get_user_pages_fast() | |
4466 | * and kmap_atomic/kunmap_atomic() we can get access to the | |
4467 | * pages directly. We then write the data directly into the | |
4468 | * ring buffer. | |
4469 | */ | |
4470 | BUILD_BUG_ON(TRACE_BUF_SIZE >= PAGE_SIZE); | |
5bf9a1ee | 4471 | |
d696b58c SR |
4472 | /* check if we cross pages */ |
4473 | if ((addr & PAGE_MASK) != ((addr + cnt) & PAGE_MASK)) | |
4474 | nr_pages = 2; | |
4475 | ||
4476 | offset = addr & (PAGE_SIZE - 1); | |
4477 | addr &= PAGE_MASK; | |
4478 | ||
4479 | ret = get_user_pages_fast(addr, nr_pages, 0, pages); | |
4480 | if (ret < nr_pages) { | |
4481 | while (--ret >= 0) | |
4482 | put_page(pages[ret]); | |
4483 | written = -EFAULT; | |
4484 | goto out; | |
5bf9a1ee | 4485 | } |
d696b58c | 4486 | |
6edb2a8a SR |
4487 | for (i = 0; i < nr_pages; i++) |
4488 | map_page[i] = kmap_atomic(pages[i]); | |
d696b58c SR |
4489 | |
4490 | local_save_flags(irq_flags); | |
4491 | size = sizeof(*entry) + cnt + 2; /* possible \n added */ | |
2d71619c | 4492 | buffer = tr->trace_buffer.buffer; |
d696b58c SR |
4493 | event = trace_buffer_lock_reserve(buffer, TRACE_PRINT, size, |
4494 | irq_flags, preempt_count()); | |
4495 | if (!event) { | |
4496 | /* Ring buffer disabled, return as if not open for write */ | |
4497 | written = -EBADF; | |
4498 | goto out_unlock; | |
5bf9a1ee | 4499 | } |
d696b58c SR |
4500 | |
4501 | entry = ring_buffer_event_data(event); | |
4502 | entry->ip = _THIS_IP_; | |
4503 | ||
4504 | if (nr_pages == 2) { | |
4505 | len = PAGE_SIZE - offset; | |
6edb2a8a SR |
4506 | memcpy(&entry->buf, map_page[0] + offset, len); |
4507 | memcpy(&entry->buf[len], map_page[1], cnt - len); | |
c13d2f7c | 4508 | } else |
6edb2a8a | 4509 | memcpy(&entry->buf, map_page[0] + offset, cnt); |
5bf9a1ee | 4510 | |
d696b58c SR |
4511 | if (entry->buf[cnt - 1] != '\n') { |
4512 | entry->buf[cnt] = '\n'; | |
4513 | entry->buf[cnt + 1] = '\0'; | |
4514 | } else | |
4515 | entry->buf[cnt] = '\0'; | |
4516 | ||
7ffbd48d | 4517 | __buffer_unlock_commit(buffer, event); |
5bf9a1ee | 4518 | |
d696b58c | 4519 | written = cnt; |
5bf9a1ee | 4520 | |
d696b58c | 4521 | *fpos += written; |
1aa54bca | 4522 | |
d696b58c | 4523 | out_unlock: |
6edb2a8a SR |
4524 | for (i = 0; i < nr_pages; i++){ |
4525 | kunmap_atomic(map_page[i]); | |
4526 | put_page(pages[i]); | |
4527 | } | |
d696b58c | 4528 | out: |
1aa54bca | 4529 | return written; |
5bf9a1ee PP |
4530 | } |
4531 | ||
13f16d20 | 4532 | static int tracing_clock_show(struct seq_file *m, void *v) |
5079f326 | 4533 | { |
2b6080f2 | 4534 | struct trace_array *tr = m->private; |
5079f326 Z |
4535 | int i; |
4536 | ||
4537 | for (i = 0; i < ARRAY_SIZE(trace_clocks); i++) | |
13f16d20 | 4538 | seq_printf(m, |
5079f326 | 4539 | "%s%s%s%s", i ? " " : "", |
2b6080f2 SR |
4540 | i == tr->clock_id ? "[" : "", trace_clocks[i].name, |
4541 | i == tr->clock_id ? "]" : ""); | |
13f16d20 | 4542 | seq_putc(m, '\n'); |
5079f326 | 4543 | |
13f16d20 | 4544 | return 0; |
5079f326 Z |
4545 | } |
4546 | ||
4547 | static ssize_t tracing_clock_write(struct file *filp, const char __user *ubuf, | |
4548 | size_t cnt, loff_t *fpos) | |
4549 | { | |
2b6080f2 SR |
4550 | struct seq_file *m = filp->private_data; |
4551 | struct trace_array *tr = m->private; | |
5079f326 Z |
4552 | char buf[64]; |
4553 | const char *clockstr; | |
4554 | int i; | |
4555 | ||
4556 | if (cnt >= sizeof(buf)) | |
4557 | return -EINVAL; | |
4558 | ||
4559 | if (copy_from_user(&buf, ubuf, cnt)) | |
4560 | return -EFAULT; | |
4561 | ||
4562 | buf[cnt] = 0; | |
4563 | ||
4564 | clockstr = strstrip(buf); | |
4565 | ||
4566 | for (i = 0; i < ARRAY_SIZE(trace_clocks); i++) { | |
4567 | if (strcmp(trace_clocks[i].name, clockstr) == 0) | |
4568 | break; | |
4569 | } | |
4570 | if (i == ARRAY_SIZE(trace_clocks)) | |
4571 | return -EINVAL; | |
4572 | ||
5079f326 Z |
4573 | mutex_lock(&trace_types_lock); |
4574 | ||
2b6080f2 SR |
4575 | tr->clock_id = i; |
4576 | ||
12883efb | 4577 | ring_buffer_set_clock(tr->trace_buffer.buffer, trace_clocks[i].func); |
5079f326 | 4578 | |
60303ed3 DS |
4579 | /* |
4580 | * New clock may not be consistent with the previous clock. | |
4581 | * Reset the buffer so that it doesn't have incomparable timestamps. | |
4582 | */ | |
12883efb SRRH |
4583 | tracing_reset_online_cpus(&global_trace.trace_buffer); |
4584 | ||
4585 | #ifdef CONFIG_TRACER_MAX_TRACE | |
4586 | if (tr->flags & TRACE_ARRAY_FL_GLOBAL && tr->max_buffer.buffer) | |
4587 | ring_buffer_set_clock(tr->max_buffer.buffer, trace_clocks[i].func); | |
4588 | tracing_reset_online_cpus(&global_trace.max_buffer); | |
4589 | #endif | |
60303ed3 | 4590 | |
5079f326 Z |
4591 | mutex_unlock(&trace_types_lock); |
4592 | ||
4593 | *fpos += cnt; | |
4594 | ||
4595 | return cnt; | |
4596 | } | |
4597 | ||
13f16d20 LZ |
4598 | static int tracing_clock_open(struct inode *inode, struct file *file) |
4599 | { | |
4600 | if (tracing_disabled) | |
4601 | return -ENODEV; | |
2b6080f2 SR |
4602 | |
4603 | return single_open(file, tracing_clock_show, inode->i_private); | |
13f16d20 LZ |
4604 | } |
4605 | ||
6de58e62 SRRH |
4606 | struct ftrace_buffer_info { |
4607 | struct trace_iterator iter; | |
4608 | void *spare; | |
4609 | unsigned int read; | |
4610 | }; | |
4611 | ||
debdd57f HT |
4612 | #ifdef CONFIG_TRACER_SNAPSHOT |
4613 | static int tracing_snapshot_open(struct inode *inode, struct file *file) | |
4614 | { | |
2b6080f2 | 4615 | struct trace_cpu *tc = inode->i_private; |
ff451961 | 4616 | struct trace_array *tr = tc->tr; |
debdd57f | 4617 | struct trace_iterator *iter; |
2b6080f2 | 4618 | struct seq_file *m; |
debdd57f HT |
4619 | int ret = 0; |
4620 | ||
ff451961 SRRH |
4621 | if (trace_array_get(tr) < 0) |
4622 | return -ENODEV; | |
4623 | ||
debdd57f | 4624 | if (file->f_mode & FMODE_READ) { |
ff451961 | 4625 | iter = __tracing_open(tr, tc, inode, file, true); |
debdd57f HT |
4626 | if (IS_ERR(iter)) |
4627 | ret = PTR_ERR(iter); | |
2b6080f2 SR |
4628 | } else { |
4629 | /* Writes still need the seq_file to hold the private data */ | |
4630 | m = kzalloc(sizeof(*m), GFP_KERNEL); | |
4631 | if (!m) | |
4632 | return -ENOMEM; | |
4633 | iter = kzalloc(sizeof(*iter), GFP_KERNEL); | |
4634 | if (!iter) { | |
4635 | kfree(m); | |
4636 | return -ENOMEM; | |
4637 | } | |
ff451961 | 4638 | iter->tr = tr; |
12883efb | 4639 | iter->trace_buffer = &tc->tr->max_buffer; |
f1affcaa | 4640 | iter->cpu_file = tc->cpu; |
2b6080f2 SR |
4641 | m->private = iter; |
4642 | file->private_data = m; | |
debdd57f | 4643 | } |
2b6080f2 | 4644 | |
ff451961 SRRH |
4645 | if (ret < 0) |
4646 | trace_array_put(tr); | |
4647 | ||
debdd57f HT |
4648 | return ret; |
4649 | } | |
4650 | ||
4651 | static ssize_t | |
4652 | tracing_snapshot_write(struct file *filp, const char __user *ubuf, size_t cnt, | |
4653 | loff_t *ppos) | |
4654 | { | |
2b6080f2 SR |
4655 | struct seq_file *m = filp->private_data; |
4656 | struct trace_iterator *iter = m->private; | |
4657 | struct trace_array *tr = iter->tr; | |
debdd57f HT |
4658 | unsigned long val; |
4659 | int ret; | |
4660 | ||
4661 | ret = tracing_update_buffers(); | |
4662 | if (ret < 0) | |
4663 | return ret; | |
4664 | ||
4665 | ret = kstrtoul_from_user(ubuf, cnt, 10, &val); | |
4666 | if (ret) | |
4667 | return ret; | |
4668 | ||
4669 | mutex_lock(&trace_types_lock); | |
4670 | ||
2b6080f2 | 4671 | if (tr->current_trace->use_max_tr) { |
debdd57f HT |
4672 | ret = -EBUSY; |
4673 | goto out; | |
4674 | } | |
4675 | ||
4676 | switch (val) { | |
4677 | case 0: | |
f1affcaa SRRH |
4678 | if (iter->cpu_file != RING_BUFFER_ALL_CPUS) { |
4679 | ret = -EINVAL; | |
4680 | break; | |
debdd57f | 4681 | } |
3209cff4 SRRH |
4682 | if (tr->allocated_snapshot) |
4683 | free_snapshot(tr); | |
debdd57f HT |
4684 | break; |
4685 | case 1: | |
f1affcaa SRRH |
4686 | /* Only allow per-cpu swap if the ring buffer supports it */ |
4687 | #ifndef CONFIG_RING_BUFFER_ALLOW_SWAP | |
4688 | if (iter->cpu_file != RING_BUFFER_ALL_CPUS) { | |
4689 | ret = -EINVAL; | |
4690 | break; | |
4691 | } | |
4692 | #endif | |
45ad21ca | 4693 | if (!tr->allocated_snapshot) { |
3209cff4 | 4694 | ret = alloc_snapshot(tr); |
debdd57f HT |
4695 | if (ret < 0) |
4696 | break; | |
debdd57f | 4697 | } |
debdd57f HT |
4698 | local_irq_disable(); |
4699 | /* Now, we're going to swap */ | |
f1affcaa | 4700 | if (iter->cpu_file == RING_BUFFER_ALL_CPUS) |
ce9bae55 | 4701 | update_max_tr(tr, current, smp_processor_id()); |
f1affcaa | 4702 | else |
ce9bae55 | 4703 | update_max_tr_single(tr, current, iter->cpu_file); |
debdd57f HT |
4704 | local_irq_enable(); |
4705 | break; | |
4706 | default: | |
45ad21ca | 4707 | if (tr->allocated_snapshot) { |
f1affcaa SRRH |
4708 | if (iter->cpu_file == RING_BUFFER_ALL_CPUS) |
4709 | tracing_reset_online_cpus(&tr->max_buffer); | |
4710 | else | |
4711 | tracing_reset(&tr->max_buffer, iter->cpu_file); | |
4712 | } | |
debdd57f HT |
4713 | break; |
4714 | } | |
4715 | ||
4716 | if (ret >= 0) { | |
4717 | *ppos += cnt; | |
4718 | ret = cnt; | |
4719 | } | |
4720 | out: | |
4721 | mutex_unlock(&trace_types_lock); | |
4722 | return ret; | |
4723 | } | |
2b6080f2 SR |
4724 | |
4725 | static int tracing_snapshot_release(struct inode *inode, struct file *file) | |
4726 | { | |
4727 | struct seq_file *m = file->private_data; | |
ff451961 SRRH |
4728 | int ret; |
4729 | ||
4730 | ret = tracing_release(inode, file); | |
2b6080f2 SR |
4731 | |
4732 | if (file->f_mode & FMODE_READ) | |
ff451961 | 4733 | return ret; |
2b6080f2 SR |
4734 | |
4735 | /* If write only, the seq_file is just a stub */ | |
4736 | if (m) | |
4737 | kfree(m->private); | |
4738 | kfree(m); | |
4739 | ||
4740 | return 0; | |
4741 | } | |
4742 | ||
6de58e62 SRRH |
4743 | static int tracing_buffers_open(struct inode *inode, struct file *filp); |
4744 | static ssize_t tracing_buffers_read(struct file *filp, char __user *ubuf, | |
4745 | size_t count, loff_t *ppos); | |
4746 | static int tracing_buffers_release(struct inode *inode, struct file *file); | |
4747 | static ssize_t tracing_buffers_splice_read(struct file *file, loff_t *ppos, | |
4748 | struct pipe_inode_info *pipe, size_t len, unsigned int flags); | |
4749 | ||
4750 | static int snapshot_raw_open(struct inode *inode, struct file *filp) | |
4751 | { | |
4752 | struct ftrace_buffer_info *info; | |
4753 | int ret; | |
4754 | ||
4755 | ret = tracing_buffers_open(inode, filp); | |
4756 | if (ret < 0) | |
4757 | return ret; | |
4758 | ||
4759 | info = filp->private_data; | |
4760 | ||
4761 | if (info->iter.trace->use_max_tr) { | |
4762 | tracing_buffers_release(inode, filp); | |
4763 | return -EBUSY; | |
4764 | } | |
4765 | ||
4766 | info->iter.snapshot = true; | |
4767 | info->iter.trace_buffer = &info->iter.tr->max_buffer; | |
4768 | ||
4769 | return ret; | |
4770 | } | |
4771 | ||
debdd57f HT |
4772 | #endif /* CONFIG_TRACER_SNAPSHOT */ |
4773 | ||
4774 | ||
5e2336a0 | 4775 | static const struct file_operations tracing_max_lat_fops = { |
4bf39a94 IM |
4776 | .open = tracing_open_generic, |
4777 | .read = tracing_max_lat_read, | |
4778 | .write = tracing_max_lat_write, | |
b444786f | 4779 | .llseek = generic_file_llseek, |
bc0c38d1 SR |
4780 | }; |
4781 | ||
5e2336a0 | 4782 | static const struct file_operations set_tracer_fops = { |
4bf39a94 IM |
4783 | .open = tracing_open_generic, |
4784 | .read = tracing_set_trace_read, | |
4785 | .write = tracing_set_trace_write, | |
b444786f | 4786 | .llseek = generic_file_llseek, |
bc0c38d1 SR |
4787 | }; |
4788 | ||
5e2336a0 | 4789 | static const struct file_operations tracing_pipe_fops = { |
4bf39a94 | 4790 | .open = tracing_open_pipe, |
2a2cc8f7 | 4791 | .poll = tracing_poll_pipe, |
4bf39a94 | 4792 | .read = tracing_read_pipe, |
3c56819b | 4793 | .splice_read = tracing_splice_read_pipe, |
4bf39a94 | 4794 | .release = tracing_release_pipe, |
b444786f | 4795 | .llseek = no_llseek, |
b3806b43 SR |
4796 | }; |
4797 | ||
5e2336a0 | 4798 | static const struct file_operations tracing_entries_fops = { |
2b6080f2 | 4799 | .open = tracing_open_generic, |
a98a3c3f SR |
4800 | .read = tracing_entries_read, |
4801 | .write = tracing_entries_write, | |
b444786f | 4802 | .llseek = generic_file_llseek, |
a98a3c3f SR |
4803 | }; |
4804 | ||
f81ab074 VN |
4805 | static const struct file_operations tracing_total_entries_fops = { |
4806 | .open = tracing_open_generic, | |
4807 | .read = tracing_total_entries_read, | |
4808 | .llseek = generic_file_llseek, | |
4809 | }; | |
4810 | ||
4f271a2a VN |
4811 | static const struct file_operations tracing_free_buffer_fops = { |
4812 | .write = tracing_free_buffer_write, | |
4813 | .release = tracing_free_buffer_release, | |
4814 | }; | |
4815 | ||
5e2336a0 | 4816 | static const struct file_operations tracing_mark_fops = { |
43a15386 | 4817 | .open = tracing_open_generic, |
5bf9a1ee | 4818 | .write = tracing_mark_write, |
b444786f | 4819 | .llseek = generic_file_llseek, |
5bf9a1ee PP |
4820 | }; |
4821 | ||
5079f326 | 4822 | static const struct file_operations trace_clock_fops = { |
13f16d20 LZ |
4823 | .open = tracing_clock_open, |
4824 | .read = seq_read, | |
4825 | .llseek = seq_lseek, | |
4826 | .release = single_release, | |
5079f326 Z |
4827 | .write = tracing_clock_write, |
4828 | }; | |
4829 | ||
debdd57f HT |
4830 | #ifdef CONFIG_TRACER_SNAPSHOT |
4831 | static const struct file_operations snapshot_fops = { | |
4832 | .open = tracing_snapshot_open, | |
4833 | .read = seq_read, | |
4834 | .write = tracing_snapshot_write, | |
4835 | .llseek = tracing_seek, | |
2b6080f2 | 4836 | .release = tracing_snapshot_release, |
debdd57f | 4837 | }; |
debdd57f | 4838 | |
6de58e62 SRRH |
4839 | static const struct file_operations snapshot_raw_fops = { |
4840 | .open = snapshot_raw_open, | |
4841 | .read = tracing_buffers_read, | |
4842 | .release = tracing_buffers_release, | |
4843 | .splice_read = tracing_buffers_splice_read, | |
4844 | .llseek = no_llseek, | |
2cadf913 SR |
4845 | }; |
4846 | ||
6de58e62 SRRH |
4847 | #endif /* CONFIG_TRACER_SNAPSHOT */ |
4848 | ||
2cadf913 SR |
4849 | static int tracing_buffers_open(struct inode *inode, struct file *filp) |
4850 | { | |
2b6080f2 SR |
4851 | struct trace_cpu *tc = inode->i_private; |
4852 | struct trace_array *tr = tc->tr; | |
2cadf913 SR |
4853 | struct ftrace_buffer_info *info; |
4854 | ||
4855 | if (tracing_disabled) | |
4856 | return -ENODEV; | |
4857 | ||
4858 | info = kzalloc(sizeof(*info), GFP_KERNEL); | |
4859 | if (!info) | |
4860 | return -ENOMEM; | |
4861 | ||
a695cb58 SRRH |
4862 | mutex_lock(&trace_types_lock); |
4863 | ||
4864 | tr->ref++; | |
4865 | ||
cc60cdc9 SR |
4866 | info->iter.tr = tr; |
4867 | info->iter.cpu_file = tc->cpu; | |
b627344f | 4868 | info->iter.trace = tr->current_trace; |
12883efb | 4869 | info->iter.trace_buffer = &tr->trace_buffer; |
cc60cdc9 | 4870 | info->spare = NULL; |
2cadf913 | 4871 | /* Force reading ring buffer for first read */ |
cc60cdc9 | 4872 | info->read = (unsigned int)-1; |
2cadf913 SR |
4873 | |
4874 | filp->private_data = info; | |
4875 | ||
a695cb58 SRRH |
4876 | mutex_unlock(&trace_types_lock); |
4877 | ||
d1e7e02f | 4878 | return nonseekable_open(inode, filp); |
2cadf913 SR |
4879 | } |
4880 | ||
cc60cdc9 SR |
4881 | static unsigned int |
4882 | tracing_buffers_poll(struct file *filp, poll_table *poll_table) | |
4883 | { | |
4884 | struct ftrace_buffer_info *info = filp->private_data; | |
4885 | struct trace_iterator *iter = &info->iter; | |
4886 | ||
4887 | return trace_poll(iter, filp, poll_table); | |
4888 | } | |
4889 | ||
2cadf913 SR |
4890 | static ssize_t |
4891 | tracing_buffers_read(struct file *filp, char __user *ubuf, | |
4892 | size_t count, loff_t *ppos) | |
4893 | { | |
4894 | struct ftrace_buffer_info *info = filp->private_data; | |
cc60cdc9 | 4895 | struct trace_iterator *iter = &info->iter; |
2cadf913 | 4896 | ssize_t ret; |
6de58e62 | 4897 | ssize_t size; |
2cadf913 | 4898 | |
2dc5d12b SR |
4899 | if (!count) |
4900 | return 0; | |
4901 | ||
6de58e62 SRRH |
4902 | mutex_lock(&trace_types_lock); |
4903 | ||
4904 | #ifdef CONFIG_TRACER_MAX_TRACE | |
4905 | if (iter->snapshot && iter->tr->current_trace->use_max_tr) { | |
4906 | size = -EBUSY; | |
4907 | goto out_unlock; | |
4908 | } | |
4909 | #endif | |
4910 | ||
ddd538f3 | 4911 | if (!info->spare) |
12883efb SRRH |
4912 | info->spare = ring_buffer_alloc_read_page(iter->trace_buffer->buffer, |
4913 | iter->cpu_file); | |
6de58e62 | 4914 | size = -ENOMEM; |
ddd538f3 | 4915 | if (!info->spare) |
6de58e62 | 4916 | goto out_unlock; |
ddd538f3 | 4917 | |
2cadf913 SR |
4918 | /* Do we have previous read data to read? */ |
4919 | if (info->read < PAGE_SIZE) | |
4920 | goto read; | |
4921 | ||
b627344f | 4922 | again: |
cc60cdc9 | 4923 | trace_access_lock(iter->cpu_file); |
12883efb | 4924 | ret = ring_buffer_read_page(iter->trace_buffer->buffer, |
2cadf913 SR |
4925 | &info->spare, |
4926 | count, | |
cc60cdc9 SR |
4927 | iter->cpu_file, 0); |
4928 | trace_access_unlock(iter->cpu_file); | |
2cadf913 | 4929 | |
b627344f SR |
4930 | if (ret < 0) { |
4931 | if (trace_empty(iter)) { | |
6de58e62 SRRH |
4932 | if ((filp->f_flags & O_NONBLOCK)) { |
4933 | size = -EAGAIN; | |
4934 | goto out_unlock; | |
4935 | } | |
4936 | mutex_unlock(&trace_types_lock); | |
b627344f | 4937 | iter->trace->wait_pipe(iter); |
6de58e62 SRRH |
4938 | mutex_lock(&trace_types_lock); |
4939 | if (signal_pending(current)) { | |
4940 | size = -EINTR; | |
4941 | goto out_unlock; | |
4942 | } | |
b627344f SR |
4943 | goto again; |
4944 | } | |
6de58e62 SRRH |
4945 | size = 0; |
4946 | goto out_unlock; | |
b627344f | 4947 | } |
436fc280 | 4948 | |
436fc280 | 4949 | info->read = 0; |
b627344f | 4950 | read: |
2cadf913 SR |
4951 | size = PAGE_SIZE - info->read; |
4952 | if (size > count) | |
4953 | size = count; | |
4954 | ||
4955 | ret = copy_to_user(ubuf, info->spare + info->read, size); | |
6de58e62 SRRH |
4956 | if (ret == size) { |
4957 | size = -EFAULT; | |
4958 | goto out_unlock; | |
4959 | } | |
2dc5d12b SR |
4960 | size -= ret; |
4961 | ||
2cadf913 SR |
4962 | *ppos += size; |
4963 | info->read += size; | |
4964 | ||
6de58e62 SRRH |
4965 | out_unlock: |
4966 | mutex_unlock(&trace_types_lock); | |
4967 | ||
2cadf913 SR |
4968 | return size; |
4969 | } | |
4970 | ||
4971 | static int tracing_buffers_release(struct inode *inode, struct file *file) | |
4972 | { | |
4973 | struct ftrace_buffer_info *info = file->private_data; | |
cc60cdc9 | 4974 | struct trace_iterator *iter = &info->iter; |
2cadf913 | 4975 | |
a695cb58 SRRH |
4976 | mutex_lock(&trace_types_lock); |
4977 | ||
ff451961 | 4978 | __trace_array_put(iter->tr); |
2cadf913 | 4979 | |
ddd538f3 | 4980 | if (info->spare) |
12883efb | 4981 | ring_buffer_free_read_page(iter->trace_buffer->buffer, info->spare); |
2cadf913 SR |
4982 | kfree(info); |
4983 | ||
a695cb58 SRRH |
4984 | mutex_unlock(&trace_types_lock); |
4985 | ||
2cadf913 SR |
4986 | return 0; |
4987 | } | |
4988 | ||
4989 | struct buffer_ref { | |
4990 | struct ring_buffer *buffer; | |
4991 | void *page; | |
4992 | int ref; | |
4993 | }; | |
4994 | ||
4995 | static void buffer_pipe_buf_release(struct pipe_inode_info *pipe, | |
4996 | struct pipe_buffer *buf) | |
4997 | { | |
4998 | struct buffer_ref *ref = (struct buffer_ref *)buf->private; | |
4999 | ||
5000 | if (--ref->ref) | |
5001 | return; | |
5002 | ||
5003 | ring_buffer_free_read_page(ref->buffer, ref->page); | |
5004 | kfree(ref); | |
5005 | buf->private = 0; | |
5006 | } | |
5007 | ||
2cadf913 SR |
5008 | static void buffer_pipe_buf_get(struct pipe_inode_info *pipe, |
5009 | struct pipe_buffer *buf) | |
5010 | { | |
5011 | struct buffer_ref *ref = (struct buffer_ref *)buf->private; | |
5012 | ||
5013 | ref->ref++; | |
5014 | } | |
5015 | ||
5016 | /* Pipe buffer operations for a buffer. */ | |
28dfef8f | 5017 | static const struct pipe_buf_operations buffer_pipe_buf_ops = { |
2cadf913 SR |
5018 | .can_merge = 0, |
5019 | .map = generic_pipe_buf_map, | |
5020 | .unmap = generic_pipe_buf_unmap, | |
5021 | .confirm = generic_pipe_buf_confirm, | |
5022 | .release = buffer_pipe_buf_release, | |
d55cb6cf | 5023 | .steal = generic_pipe_buf_steal, |
2cadf913 SR |
5024 | .get = buffer_pipe_buf_get, |
5025 | }; | |
5026 | ||
5027 | /* | |
5028 | * Callback from splice_to_pipe(), if we need to release some pages | |
5029 | * at the end of the spd in case we error'ed out in filling the pipe. | |
5030 | */ | |
5031 | static void buffer_spd_release(struct splice_pipe_desc *spd, unsigned int i) | |
5032 | { | |
5033 | struct buffer_ref *ref = | |
5034 | (struct buffer_ref *)spd->partial[i].private; | |
5035 | ||
5036 | if (--ref->ref) | |
5037 | return; | |
5038 | ||
5039 | ring_buffer_free_read_page(ref->buffer, ref->page); | |
5040 | kfree(ref); | |
5041 | spd->partial[i].private = 0; | |
5042 | } | |
5043 | ||
5044 | static ssize_t | |
5045 | tracing_buffers_splice_read(struct file *file, loff_t *ppos, | |
5046 | struct pipe_inode_info *pipe, size_t len, | |
5047 | unsigned int flags) | |
5048 | { | |
5049 | struct ftrace_buffer_info *info = file->private_data; | |
cc60cdc9 | 5050 | struct trace_iterator *iter = &info->iter; |
35f3d14d JA |
5051 | struct partial_page partial_def[PIPE_DEF_BUFFERS]; |
5052 | struct page *pages_def[PIPE_DEF_BUFFERS]; | |
2cadf913 | 5053 | struct splice_pipe_desc spd = { |
35f3d14d JA |
5054 | .pages = pages_def, |
5055 | .partial = partial_def, | |
047fe360 | 5056 | .nr_pages_max = PIPE_DEF_BUFFERS, |
2cadf913 SR |
5057 | .flags = flags, |
5058 | .ops = &buffer_pipe_buf_ops, | |
5059 | .spd_release = buffer_spd_release, | |
5060 | }; | |
5061 | struct buffer_ref *ref; | |
93459c6c | 5062 | int entries, size, i; |
6de58e62 | 5063 | ssize_t ret; |
2cadf913 | 5064 | |
6de58e62 SRRH |
5065 | mutex_lock(&trace_types_lock); |
5066 | ||
5067 | #ifdef CONFIG_TRACER_MAX_TRACE | |
5068 | if (iter->snapshot && iter->tr->current_trace->use_max_tr) { | |
5069 | ret = -EBUSY; | |
5070 | goto out; | |
5071 | } | |
5072 | #endif | |
5073 | ||
5074 | if (splice_grow_spd(pipe, &spd)) { | |
5075 | ret = -ENOMEM; | |
5076 | goto out; | |
5077 | } | |
35f3d14d | 5078 | |
93cfb3c9 | 5079 | if (*ppos & (PAGE_SIZE - 1)) { |
35f3d14d JA |
5080 | ret = -EINVAL; |
5081 | goto out; | |
93cfb3c9 LJ |
5082 | } |
5083 | ||
5084 | if (len & (PAGE_SIZE - 1)) { | |
35f3d14d JA |
5085 | if (len < PAGE_SIZE) { |
5086 | ret = -EINVAL; | |
5087 | goto out; | |
5088 | } | |
93cfb3c9 LJ |
5089 | len &= PAGE_MASK; |
5090 | } | |
5091 | ||
cc60cdc9 SR |
5092 | again: |
5093 | trace_access_lock(iter->cpu_file); | |
12883efb | 5094 | entries = ring_buffer_entries_cpu(iter->trace_buffer->buffer, iter->cpu_file); |
93459c6c | 5095 | |
35f3d14d | 5096 | for (i = 0; i < pipe->buffers && len && entries; i++, len -= PAGE_SIZE) { |
2cadf913 SR |
5097 | struct page *page; |
5098 | int r; | |
5099 | ||
5100 | ref = kzalloc(sizeof(*ref), GFP_KERNEL); | |
5101 | if (!ref) | |
5102 | break; | |
5103 | ||
7267fa68 | 5104 | ref->ref = 1; |
12883efb | 5105 | ref->buffer = iter->trace_buffer->buffer; |
cc60cdc9 | 5106 | ref->page = ring_buffer_alloc_read_page(ref->buffer, iter->cpu_file); |
2cadf913 SR |
5107 | if (!ref->page) { |
5108 | kfree(ref); | |
5109 | break; | |
5110 | } | |
5111 | ||
5112 | r = ring_buffer_read_page(ref->buffer, &ref->page, | |
cc60cdc9 | 5113 | len, iter->cpu_file, 1); |
2cadf913 | 5114 | if (r < 0) { |
7ea59064 | 5115 | ring_buffer_free_read_page(ref->buffer, ref->page); |
2cadf913 SR |
5116 | kfree(ref); |
5117 | break; | |
5118 | } | |
5119 | ||
5120 | /* | |
5121 | * zero out any left over data, this is going to | |
5122 | * user land. | |
5123 | */ | |
5124 | size = ring_buffer_page_len(ref->page); | |
5125 | if (size < PAGE_SIZE) | |
5126 | memset(ref->page + size, 0, PAGE_SIZE - size); | |
5127 | ||
5128 | page = virt_to_page(ref->page); | |
5129 | ||
5130 | spd.pages[i] = page; | |
5131 | spd.partial[i].len = PAGE_SIZE; | |
5132 | spd.partial[i].offset = 0; | |
5133 | spd.partial[i].private = (unsigned long)ref; | |
5134 | spd.nr_pages++; | |
93cfb3c9 | 5135 | *ppos += PAGE_SIZE; |
93459c6c | 5136 | |
12883efb | 5137 | entries = ring_buffer_entries_cpu(iter->trace_buffer->buffer, iter->cpu_file); |
2cadf913 SR |
5138 | } |
5139 | ||
cc60cdc9 | 5140 | trace_access_unlock(iter->cpu_file); |
2cadf913 SR |
5141 | spd.nr_pages = i; |
5142 | ||
5143 | /* did we read anything? */ | |
5144 | if (!spd.nr_pages) { | |
cc60cdc9 | 5145 | if ((file->f_flags & O_NONBLOCK) || (flags & SPLICE_F_NONBLOCK)) { |
2cadf913 | 5146 | ret = -EAGAIN; |
cc60cdc9 SR |
5147 | goto out; |
5148 | } | |
6de58e62 | 5149 | mutex_unlock(&trace_types_lock); |
b627344f | 5150 | iter->trace->wait_pipe(iter); |
6de58e62 | 5151 | mutex_lock(&trace_types_lock); |
cc60cdc9 SR |
5152 | if (signal_pending(current)) { |
5153 | ret = -EINTR; | |
5154 | goto out; | |
5155 | } | |
5156 | goto again; | |
2cadf913 SR |
5157 | } |
5158 | ||
5159 | ret = splice_to_pipe(pipe, &spd); | |
047fe360 | 5160 | splice_shrink_spd(&spd); |
35f3d14d | 5161 | out: |
6de58e62 SRRH |
5162 | mutex_unlock(&trace_types_lock); |
5163 | ||
2cadf913 SR |
5164 | return ret; |
5165 | } | |
5166 | ||
5167 | static const struct file_operations tracing_buffers_fops = { | |
5168 | .open = tracing_buffers_open, | |
5169 | .read = tracing_buffers_read, | |
cc60cdc9 | 5170 | .poll = tracing_buffers_poll, |
2cadf913 SR |
5171 | .release = tracing_buffers_release, |
5172 | .splice_read = tracing_buffers_splice_read, | |
5173 | .llseek = no_llseek, | |
5174 | }; | |
5175 | ||
c8d77183 SR |
5176 | static ssize_t |
5177 | tracing_stats_read(struct file *filp, char __user *ubuf, | |
5178 | size_t count, loff_t *ppos) | |
5179 | { | |
2b6080f2 SR |
5180 | struct trace_cpu *tc = filp->private_data; |
5181 | struct trace_array *tr = tc->tr; | |
12883efb | 5182 | struct trace_buffer *trace_buf = &tr->trace_buffer; |
c8d77183 SR |
5183 | struct trace_seq *s; |
5184 | unsigned long cnt; | |
c64e148a VN |
5185 | unsigned long long t; |
5186 | unsigned long usec_rem; | |
2b6080f2 | 5187 | int cpu = tc->cpu; |
c8d77183 | 5188 | |
e4f2d10f | 5189 | s = kmalloc(sizeof(*s), GFP_KERNEL); |
c8d77183 | 5190 | if (!s) |
a646365c | 5191 | return -ENOMEM; |
c8d77183 SR |
5192 | |
5193 | trace_seq_init(s); | |
5194 | ||
12883efb | 5195 | cnt = ring_buffer_entries_cpu(trace_buf->buffer, cpu); |
c8d77183 SR |
5196 | trace_seq_printf(s, "entries: %ld\n", cnt); |
5197 | ||
12883efb | 5198 | cnt = ring_buffer_overrun_cpu(trace_buf->buffer, cpu); |
c8d77183 SR |
5199 | trace_seq_printf(s, "overrun: %ld\n", cnt); |
5200 | ||
12883efb | 5201 | cnt = ring_buffer_commit_overrun_cpu(trace_buf->buffer, cpu); |
c8d77183 SR |
5202 | trace_seq_printf(s, "commit overrun: %ld\n", cnt); |
5203 | ||
12883efb | 5204 | cnt = ring_buffer_bytes_cpu(trace_buf->buffer, cpu); |
c64e148a VN |
5205 | trace_seq_printf(s, "bytes: %ld\n", cnt); |
5206 | ||
11043d8b YY |
5207 | if (trace_clocks[trace_clock_id].in_ns) { |
5208 | /* local or global for trace_clock */ | |
12883efb | 5209 | t = ns2usecs(ring_buffer_oldest_event_ts(trace_buf->buffer, cpu)); |
11043d8b YY |
5210 | usec_rem = do_div(t, USEC_PER_SEC); |
5211 | trace_seq_printf(s, "oldest event ts: %5llu.%06lu\n", | |
5212 | t, usec_rem); | |
5213 | ||
12883efb | 5214 | t = ns2usecs(ring_buffer_time_stamp(trace_buf->buffer, cpu)); |
11043d8b YY |
5215 | usec_rem = do_div(t, USEC_PER_SEC); |
5216 | trace_seq_printf(s, "now ts: %5llu.%06lu\n", t, usec_rem); | |
5217 | } else { | |
5218 | /* counter or tsc mode for trace_clock */ | |
5219 | trace_seq_printf(s, "oldest event ts: %llu\n", | |
12883efb | 5220 | ring_buffer_oldest_event_ts(trace_buf->buffer, cpu)); |
c64e148a | 5221 | |
11043d8b | 5222 | trace_seq_printf(s, "now ts: %llu\n", |
12883efb | 5223 | ring_buffer_time_stamp(trace_buf->buffer, cpu)); |
11043d8b | 5224 | } |
c64e148a | 5225 | |
12883efb | 5226 | cnt = ring_buffer_dropped_events_cpu(trace_buf->buffer, cpu); |
884bfe89 SP |
5227 | trace_seq_printf(s, "dropped events: %ld\n", cnt); |
5228 | ||
12883efb | 5229 | cnt = ring_buffer_read_events_cpu(trace_buf->buffer, cpu); |
ad964704 SRRH |
5230 | trace_seq_printf(s, "read events: %ld\n", cnt); |
5231 | ||
c8d77183 SR |
5232 | count = simple_read_from_buffer(ubuf, count, ppos, s->buffer, s->len); |
5233 | ||
5234 | kfree(s); | |
5235 | ||
5236 | return count; | |
5237 | } | |
5238 | ||
5239 | static const struct file_operations tracing_stats_fops = { | |
5240 | .open = tracing_open_generic, | |
5241 | .read = tracing_stats_read, | |
b444786f | 5242 | .llseek = generic_file_llseek, |
c8d77183 SR |
5243 | }; |
5244 | ||
bc0c38d1 SR |
5245 | #ifdef CONFIG_DYNAMIC_FTRACE |
5246 | ||
b807c3d0 SR |
5247 | int __weak ftrace_arch_read_dyn_info(char *buf, int size) |
5248 | { | |
5249 | return 0; | |
5250 | } | |
5251 | ||
bc0c38d1 | 5252 | static ssize_t |
b807c3d0 | 5253 | tracing_read_dyn_info(struct file *filp, char __user *ubuf, |
bc0c38d1 SR |
5254 | size_t cnt, loff_t *ppos) |
5255 | { | |
a26a2a27 SR |
5256 | static char ftrace_dyn_info_buffer[1024]; |
5257 | static DEFINE_MUTEX(dyn_info_mutex); | |
bc0c38d1 | 5258 | unsigned long *p = filp->private_data; |
b807c3d0 | 5259 | char *buf = ftrace_dyn_info_buffer; |
a26a2a27 | 5260 | int size = ARRAY_SIZE(ftrace_dyn_info_buffer); |
bc0c38d1 SR |
5261 | int r; |
5262 | ||
b807c3d0 SR |
5263 | mutex_lock(&dyn_info_mutex); |
5264 | r = sprintf(buf, "%ld ", *p); | |
4bf39a94 | 5265 | |
a26a2a27 | 5266 | r += ftrace_arch_read_dyn_info(buf+r, (size-1)-r); |
b807c3d0 SR |
5267 | buf[r++] = '\n'; |
5268 | ||
5269 | r = simple_read_from_buffer(ubuf, cnt, ppos, buf, r); | |
5270 | ||
5271 | mutex_unlock(&dyn_info_mutex); | |
5272 | ||
5273 | return r; | |
bc0c38d1 SR |
5274 | } |
5275 | ||
5e2336a0 | 5276 | static const struct file_operations tracing_dyn_info_fops = { |
4bf39a94 | 5277 | .open = tracing_open_generic, |
b807c3d0 | 5278 | .read = tracing_read_dyn_info, |
b444786f | 5279 | .llseek = generic_file_llseek, |
bc0c38d1 | 5280 | }; |
77fd5c15 | 5281 | #endif /* CONFIG_DYNAMIC_FTRACE */ |
bc0c38d1 | 5282 | |
77fd5c15 SRRH |
5283 | #if defined(CONFIG_TRACER_SNAPSHOT) && defined(CONFIG_DYNAMIC_FTRACE) |
5284 | static void | |
5285 | ftrace_snapshot(unsigned long ip, unsigned long parent_ip, void **data) | |
5286 | { | |
5287 | tracing_snapshot(); | |
5288 | } | |
bc0c38d1 | 5289 | |
77fd5c15 SRRH |
5290 | static void |
5291 | ftrace_count_snapshot(unsigned long ip, unsigned long parent_ip, void **data) | |
bc0c38d1 | 5292 | { |
77fd5c15 SRRH |
5293 | unsigned long *count = (long *)data; |
5294 | ||
5295 | if (!*count) | |
5296 | return; | |
bc0c38d1 | 5297 | |
77fd5c15 SRRH |
5298 | if (*count != -1) |
5299 | (*count)--; | |
5300 | ||
5301 | tracing_snapshot(); | |
5302 | } | |
5303 | ||
5304 | static int | |
5305 | ftrace_snapshot_print(struct seq_file *m, unsigned long ip, | |
5306 | struct ftrace_probe_ops *ops, void *data) | |
5307 | { | |
5308 | long count = (long)data; | |
5309 | ||
5310 | seq_printf(m, "%ps:", (void *)ip); | |
5311 | ||
5312 | seq_printf(m, "snapshot"); | |
5313 | ||
5314 | if (count == -1) | |
5315 | seq_printf(m, ":unlimited\n"); | |
5316 | else | |
5317 | seq_printf(m, ":count=%ld\n", count); | |
5318 | ||
5319 | return 0; | |
5320 | } | |
5321 | ||
5322 | static struct ftrace_probe_ops snapshot_probe_ops = { | |
5323 | .func = ftrace_snapshot, | |
5324 | .print = ftrace_snapshot_print, | |
5325 | }; | |
5326 | ||
5327 | static struct ftrace_probe_ops snapshot_count_probe_ops = { | |
5328 | .func = ftrace_count_snapshot, | |
5329 | .print = ftrace_snapshot_print, | |
5330 | }; | |
5331 | ||
5332 | static int | |
5333 | ftrace_trace_snapshot_callback(struct ftrace_hash *hash, | |
5334 | char *glob, char *cmd, char *param, int enable) | |
5335 | { | |
5336 | struct ftrace_probe_ops *ops; | |
5337 | void *count = (void *)-1; | |
5338 | char *number; | |
5339 | int ret; | |
5340 | ||
5341 | /* hash funcs only work with set_ftrace_filter */ | |
5342 | if (!enable) | |
5343 | return -EINVAL; | |
5344 | ||
5345 | ops = param ? &snapshot_count_probe_ops : &snapshot_probe_ops; | |
5346 | ||
5347 | if (glob[0] == '!') { | |
5348 | unregister_ftrace_function_probe_func(glob+1, ops); | |
5349 | return 0; | |
5350 | } | |
5351 | ||
5352 | if (!param) | |
5353 | goto out_reg; | |
5354 | ||
5355 | number = strsep(¶m, ":"); | |
5356 | ||
5357 | if (!strlen(number)) | |
5358 | goto out_reg; | |
5359 | ||
5360 | /* | |
5361 | * We use the callback data field (which is a pointer) | |
5362 | * as our counter. | |
5363 | */ | |
5364 | ret = kstrtoul(number, 0, (unsigned long *)&count); | |
5365 | if (ret) | |
5366 | return ret; | |
5367 | ||
5368 | out_reg: | |
5369 | ret = register_ftrace_function_probe(glob, ops, count); | |
5370 | ||
5371 | if (ret >= 0) | |
5372 | alloc_snapshot(&global_trace); | |
5373 | ||
5374 | return ret < 0 ? ret : 0; | |
5375 | } | |
5376 | ||
5377 | static struct ftrace_func_command ftrace_snapshot_cmd = { | |
5378 | .name = "snapshot", | |
5379 | .func = ftrace_trace_snapshot_callback, | |
5380 | }; | |
5381 | ||
5382 | static int register_snapshot_cmd(void) | |
5383 | { | |
5384 | return register_ftrace_command(&ftrace_snapshot_cmd); | |
5385 | } | |
5386 | #else | |
5387 | static inline int register_snapshot_cmd(void) { return 0; } | |
5388 | #endif /* defined(CONFIG_TRACER_SNAPSHOT) && defined(CONFIG_DYNAMIC_FTRACE) */ | |
bc0c38d1 | 5389 | |
2b6080f2 | 5390 | struct dentry *tracing_init_dentry_tr(struct trace_array *tr) |
bc0c38d1 | 5391 | { |
2b6080f2 SR |
5392 | if (tr->dir) |
5393 | return tr->dir; | |
bc0c38d1 | 5394 | |
3e1f60b8 FW |
5395 | if (!debugfs_initialized()) |
5396 | return NULL; | |
5397 | ||
2b6080f2 SR |
5398 | if (tr->flags & TRACE_ARRAY_FL_GLOBAL) |
5399 | tr->dir = debugfs_create_dir("tracing", NULL); | |
bc0c38d1 | 5400 | |
687c878a J |
5401 | if (!tr->dir) |
5402 | pr_warn_once("Could not create debugfs directory 'tracing'\n"); | |
bc0c38d1 | 5403 | |
2b6080f2 | 5404 | return tr->dir; |
bc0c38d1 SR |
5405 | } |
5406 | ||
2b6080f2 SR |
5407 | struct dentry *tracing_init_dentry(void) |
5408 | { | |
5409 | return tracing_init_dentry_tr(&global_trace); | |
5410 | } | |
b04cc6b1 | 5411 | |
2b6080f2 | 5412 | static struct dentry *tracing_dentry_percpu(struct trace_array *tr, int cpu) |
b04cc6b1 | 5413 | { |
b04cc6b1 FW |
5414 | struct dentry *d_tracer; |
5415 | ||
2b6080f2 SR |
5416 | if (tr->percpu_dir) |
5417 | return tr->percpu_dir; | |
b04cc6b1 | 5418 | |
2b6080f2 | 5419 | d_tracer = tracing_init_dentry_tr(tr); |
b04cc6b1 FW |
5420 | if (!d_tracer) |
5421 | return NULL; | |
5422 | ||
2b6080f2 | 5423 | tr->percpu_dir = debugfs_create_dir("per_cpu", d_tracer); |
b04cc6b1 | 5424 | |
2b6080f2 SR |
5425 | WARN_ONCE(!tr->percpu_dir, |
5426 | "Could not create debugfs directory 'per_cpu/%d'\n", cpu); | |
b04cc6b1 | 5427 | |
2b6080f2 | 5428 | return tr->percpu_dir; |
b04cc6b1 FW |
5429 | } |
5430 | ||
2b6080f2 SR |
5431 | static void |
5432 | tracing_init_debugfs_percpu(struct trace_array *tr, long cpu) | |
b04cc6b1 | 5433 | { |
12883efb | 5434 | struct trace_array_cpu *data = per_cpu_ptr(tr->trace_buffer.data, cpu); |
2b6080f2 | 5435 | struct dentry *d_percpu = tracing_dentry_percpu(tr, cpu); |
5452af66 | 5436 | struct dentry *d_cpu; |
dd49a38c | 5437 | char cpu_dir[30]; /* 30 characters should be more than enough */ |
b04cc6b1 | 5438 | |
0a3d7ce7 NK |
5439 | if (!d_percpu) |
5440 | return; | |
5441 | ||
dd49a38c | 5442 | snprintf(cpu_dir, 30, "cpu%ld", cpu); |
8656e7a2 FW |
5443 | d_cpu = debugfs_create_dir(cpu_dir, d_percpu); |
5444 | if (!d_cpu) { | |
5445 | pr_warning("Could not create debugfs '%s' entry\n", cpu_dir); | |
5446 | return; | |
5447 | } | |
b04cc6b1 | 5448 | |
8656e7a2 | 5449 | /* per cpu trace_pipe */ |
5452af66 | 5450 | trace_create_file("trace_pipe", 0444, d_cpu, |
2b6080f2 | 5451 | (void *)&data->trace_cpu, &tracing_pipe_fops); |
b04cc6b1 FW |
5452 | |
5453 | /* per cpu trace */ | |
5452af66 | 5454 | trace_create_file("trace", 0644, d_cpu, |
2b6080f2 | 5455 | (void *)&data->trace_cpu, &tracing_fops); |
7f96f93f | 5456 | |
5452af66 | 5457 | trace_create_file("trace_pipe_raw", 0444, d_cpu, |
2b6080f2 | 5458 | (void *)&data->trace_cpu, &tracing_buffers_fops); |
7f96f93f | 5459 | |
c8d77183 | 5460 | trace_create_file("stats", 0444, d_cpu, |
2b6080f2 | 5461 | (void *)&data->trace_cpu, &tracing_stats_fops); |
438ced17 VN |
5462 | |
5463 | trace_create_file("buffer_size_kb", 0444, d_cpu, | |
2b6080f2 | 5464 | (void *)&data->trace_cpu, &tracing_entries_fops); |
f1affcaa SRRH |
5465 | |
5466 | #ifdef CONFIG_TRACER_SNAPSHOT | |
5467 | trace_create_file("snapshot", 0644, d_cpu, | |
5468 | (void *)&data->trace_cpu, &snapshot_fops); | |
6de58e62 SRRH |
5469 | |
5470 | trace_create_file("snapshot_raw", 0444, d_cpu, | |
5471 | (void *)&data->trace_cpu, &snapshot_raw_fops); | |
f1affcaa | 5472 | #endif |
b04cc6b1 FW |
5473 | } |
5474 | ||
60a11774 SR |
5475 | #ifdef CONFIG_FTRACE_SELFTEST |
5476 | /* Let selftest have access to static functions in this file */ | |
5477 | #include "trace_selftest.c" | |
5478 | #endif | |
5479 | ||
577b785f SR |
5480 | struct trace_option_dentry { |
5481 | struct tracer_opt *opt; | |
5482 | struct tracer_flags *flags; | |
2b6080f2 | 5483 | struct trace_array *tr; |
577b785f SR |
5484 | struct dentry *entry; |
5485 | }; | |
5486 | ||
5487 | static ssize_t | |
5488 | trace_options_read(struct file *filp, char __user *ubuf, size_t cnt, | |
5489 | loff_t *ppos) | |
5490 | { | |
5491 | struct trace_option_dentry *topt = filp->private_data; | |
5492 | char *buf; | |
5493 | ||
5494 | if (topt->flags->val & topt->opt->bit) | |
5495 | buf = "1\n"; | |
5496 | else | |
5497 | buf = "0\n"; | |
5498 | ||
5499 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, 2); | |
5500 | } | |
5501 | ||
5502 | static ssize_t | |
5503 | trace_options_write(struct file *filp, const char __user *ubuf, size_t cnt, | |
5504 | loff_t *ppos) | |
5505 | { | |
5506 | struct trace_option_dentry *topt = filp->private_data; | |
5507 | unsigned long val; | |
577b785f SR |
5508 | int ret; |
5509 | ||
22fe9b54 PH |
5510 | ret = kstrtoul_from_user(ubuf, cnt, 10, &val); |
5511 | if (ret) | |
577b785f SR |
5512 | return ret; |
5513 | ||
8d18eaaf LZ |
5514 | if (val != 0 && val != 1) |
5515 | return -EINVAL; | |
577b785f | 5516 | |
8d18eaaf | 5517 | if (!!(topt->flags->val & topt->opt->bit) != val) { |
577b785f | 5518 | mutex_lock(&trace_types_lock); |
2b6080f2 | 5519 | ret = __set_tracer_option(topt->tr->current_trace, topt->flags, |
c757bea9 | 5520 | topt->opt, !val); |
577b785f SR |
5521 | mutex_unlock(&trace_types_lock); |
5522 | if (ret) | |
5523 | return ret; | |
577b785f SR |
5524 | } |
5525 | ||
5526 | *ppos += cnt; | |
5527 | ||
5528 | return cnt; | |
5529 | } | |
5530 | ||
5531 | ||
5532 | static const struct file_operations trace_options_fops = { | |
5533 | .open = tracing_open_generic, | |
5534 | .read = trace_options_read, | |
5535 | .write = trace_options_write, | |
b444786f | 5536 | .llseek = generic_file_llseek, |
577b785f SR |
5537 | }; |
5538 | ||
a8259075 SR |
5539 | static ssize_t |
5540 | trace_options_core_read(struct file *filp, char __user *ubuf, size_t cnt, | |
5541 | loff_t *ppos) | |
5542 | { | |
5543 | long index = (long)filp->private_data; | |
5544 | char *buf; | |
5545 | ||
5546 | if (trace_flags & (1 << index)) | |
5547 | buf = "1\n"; | |
5548 | else | |
5549 | buf = "0\n"; | |
5550 | ||
5551 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, 2); | |
5552 | } | |
5553 | ||
5554 | static ssize_t | |
5555 | trace_options_core_write(struct file *filp, const char __user *ubuf, size_t cnt, | |
5556 | loff_t *ppos) | |
5557 | { | |
2b6080f2 | 5558 | struct trace_array *tr = &global_trace; |
a8259075 | 5559 | long index = (long)filp->private_data; |
a8259075 SR |
5560 | unsigned long val; |
5561 | int ret; | |
5562 | ||
22fe9b54 PH |
5563 | ret = kstrtoul_from_user(ubuf, cnt, 10, &val); |
5564 | if (ret) | |
a8259075 SR |
5565 | return ret; |
5566 | ||
f2d84b65 | 5567 | if (val != 0 && val != 1) |
a8259075 | 5568 | return -EINVAL; |
69d34da2 SRRH |
5569 | |
5570 | mutex_lock(&trace_types_lock); | |
2b6080f2 | 5571 | ret = set_tracer_flag(tr, 1 << index, val); |
69d34da2 | 5572 | mutex_unlock(&trace_types_lock); |
a8259075 | 5573 | |
613f04a0 SRRH |
5574 | if (ret < 0) |
5575 | return ret; | |
5576 | ||
a8259075 SR |
5577 | *ppos += cnt; |
5578 | ||
5579 | return cnt; | |
5580 | } | |
5581 | ||
a8259075 SR |
5582 | static const struct file_operations trace_options_core_fops = { |
5583 | .open = tracing_open_generic, | |
5584 | .read = trace_options_core_read, | |
5585 | .write = trace_options_core_write, | |
b444786f | 5586 | .llseek = generic_file_llseek, |
a8259075 SR |
5587 | }; |
5588 | ||
5452af66 | 5589 | struct dentry *trace_create_file(const char *name, |
f4ae40a6 | 5590 | umode_t mode, |
5452af66 FW |
5591 | struct dentry *parent, |
5592 | void *data, | |
5593 | const struct file_operations *fops) | |
5594 | { | |
5595 | struct dentry *ret; | |
5596 | ||
5597 | ret = debugfs_create_file(name, mode, parent, data, fops); | |
5598 | if (!ret) | |
5599 | pr_warning("Could not create debugfs '%s' entry\n", name); | |
5600 | ||
5601 | return ret; | |
5602 | } | |
5603 | ||
5604 | ||
2b6080f2 | 5605 | static struct dentry *trace_options_init_dentry(struct trace_array *tr) |
a8259075 SR |
5606 | { |
5607 | struct dentry *d_tracer; | |
a8259075 | 5608 | |
2b6080f2 SR |
5609 | if (tr->options) |
5610 | return tr->options; | |
a8259075 | 5611 | |
2b6080f2 | 5612 | d_tracer = tracing_init_dentry_tr(tr); |
a8259075 SR |
5613 | if (!d_tracer) |
5614 | return NULL; | |
5615 | ||
2b6080f2 SR |
5616 | tr->options = debugfs_create_dir("options", d_tracer); |
5617 | if (!tr->options) { | |
a8259075 SR |
5618 | pr_warning("Could not create debugfs directory 'options'\n"); |
5619 | return NULL; | |
5620 | } | |
5621 | ||
2b6080f2 | 5622 | return tr->options; |
a8259075 SR |
5623 | } |
5624 | ||
577b785f | 5625 | static void |
2b6080f2 SR |
5626 | create_trace_option_file(struct trace_array *tr, |
5627 | struct trace_option_dentry *topt, | |
577b785f SR |
5628 | struct tracer_flags *flags, |
5629 | struct tracer_opt *opt) | |
5630 | { | |
5631 | struct dentry *t_options; | |
577b785f | 5632 | |
2b6080f2 | 5633 | t_options = trace_options_init_dentry(tr); |
577b785f SR |
5634 | if (!t_options) |
5635 | return; | |
5636 | ||
5637 | topt->flags = flags; | |
5638 | topt->opt = opt; | |
2b6080f2 | 5639 | topt->tr = tr; |
577b785f | 5640 | |
5452af66 | 5641 | topt->entry = trace_create_file(opt->name, 0644, t_options, topt, |
577b785f SR |
5642 | &trace_options_fops); |
5643 | ||
577b785f SR |
5644 | } |
5645 | ||
5646 | static struct trace_option_dentry * | |
2b6080f2 | 5647 | create_trace_option_files(struct trace_array *tr, struct tracer *tracer) |
577b785f SR |
5648 | { |
5649 | struct trace_option_dentry *topts; | |
5650 | struct tracer_flags *flags; | |
5651 | struct tracer_opt *opts; | |
5652 | int cnt; | |
5653 | ||
5654 | if (!tracer) | |
5655 | return NULL; | |
5656 | ||
5657 | flags = tracer->flags; | |
5658 | ||
5659 | if (!flags || !flags->opts) | |
5660 | return NULL; | |
5661 | ||
5662 | opts = flags->opts; | |
5663 | ||
5664 | for (cnt = 0; opts[cnt].name; cnt++) | |
5665 | ; | |
5666 | ||
0cfe8245 | 5667 | topts = kcalloc(cnt + 1, sizeof(*topts), GFP_KERNEL); |
577b785f SR |
5668 | if (!topts) |
5669 | return NULL; | |
5670 | ||
5671 | for (cnt = 0; opts[cnt].name; cnt++) | |
2b6080f2 | 5672 | create_trace_option_file(tr, &topts[cnt], flags, |
577b785f SR |
5673 | &opts[cnt]); |
5674 | ||
5675 | return topts; | |
5676 | } | |
5677 | ||
5678 | static void | |
5679 | destroy_trace_option_files(struct trace_option_dentry *topts) | |
5680 | { | |
5681 | int cnt; | |
5682 | ||
5683 | if (!topts) | |
5684 | return; | |
5685 | ||
5686 | for (cnt = 0; topts[cnt].opt; cnt++) { | |
5687 | if (topts[cnt].entry) | |
5688 | debugfs_remove(topts[cnt].entry); | |
5689 | } | |
5690 | ||
5691 | kfree(topts); | |
5692 | } | |
5693 | ||
a8259075 | 5694 | static struct dentry * |
2b6080f2 SR |
5695 | create_trace_option_core_file(struct trace_array *tr, |
5696 | const char *option, long index) | |
a8259075 SR |
5697 | { |
5698 | struct dentry *t_options; | |
a8259075 | 5699 | |
2b6080f2 | 5700 | t_options = trace_options_init_dentry(tr); |
a8259075 SR |
5701 | if (!t_options) |
5702 | return NULL; | |
5703 | ||
5452af66 | 5704 | return trace_create_file(option, 0644, t_options, (void *)index, |
a8259075 | 5705 | &trace_options_core_fops); |
a8259075 SR |
5706 | } |
5707 | ||
2b6080f2 | 5708 | static __init void create_trace_options_dir(struct trace_array *tr) |
a8259075 SR |
5709 | { |
5710 | struct dentry *t_options; | |
a8259075 SR |
5711 | int i; |
5712 | ||
2b6080f2 | 5713 | t_options = trace_options_init_dentry(tr); |
a8259075 SR |
5714 | if (!t_options) |
5715 | return; | |
5716 | ||
5452af66 | 5717 | for (i = 0; trace_options[i]; i++) |
2b6080f2 | 5718 | create_trace_option_core_file(tr, trace_options[i], i); |
a8259075 SR |
5719 | } |
5720 | ||
499e5470 SR |
5721 | static ssize_t |
5722 | rb_simple_read(struct file *filp, char __user *ubuf, | |
5723 | size_t cnt, loff_t *ppos) | |
5724 | { | |
348f0fc2 | 5725 | struct trace_array *tr = filp->private_data; |
499e5470 SR |
5726 | char buf[64]; |
5727 | int r; | |
5728 | ||
10246fa3 | 5729 | r = tracer_tracing_is_on(tr); |
499e5470 SR |
5730 | r = sprintf(buf, "%d\n", r); |
5731 | ||
5732 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, r); | |
5733 | } | |
5734 | ||
5735 | static ssize_t | |
5736 | rb_simple_write(struct file *filp, const char __user *ubuf, | |
5737 | size_t cnt, loff_t *ppos) | |
5738 | { | |
348f0fc2 | 5739 | struct trace_array *tr = filp->private_data; |
12883efb | 5740 | struct ring_buffer *buffer = tr->trace_buffer.buffer; |
499e5470 SR |
5741 | unsigned long val; |
5742 | int ret; | |
5743 | ||
5744 | ret = kstrtoul_from_user(ubuf, cnt, 10, &val); | |
5745 | if (ret) | |
5746 | return ret; | |
5747 | ||
5748 | if (buffer) { | |
2df8f8a6 SR |
5749 | mutex_lock(&trace_types_lock); |
5750 | if (val) { | |
10246fa3 | 5751 | tracer_tracing_on(tr); |
2b6080f2 SR |
5752 | if (tr->current_trace->start) |
5753 | tr->current_trace->start(tr); | |
2df8f8a6 | 5754 | } else { |
10246fa3 | 5755 | tracer_tracing_off(tr); |
2b6080f2 SR |
5756 | if (tr->current_trace->stop) |
5757 | tr->current_trace->stop(tr); | |
2df8f8a6 SR |
5758 | } |
5759 | mutex_unlock(&trace_types_lock); | |
499e5470 SR |
5760 | } |
5761 | ||
5762 | (*ppos)++; | |
5763 | ||
5764 | return cnt; | |
5765 | } | |
5766 | ||
5767 | static const struct file_operations rb_simple_fops = { | |
5768 | .open = tracing_open_generic, | |
5769 | .read = rb_simple_read, | |
5770 | .write = rb_simple_write, | |
5771 | .llseek = default_llseek, | |
5772 | }; | |
5773 | ||
277ba044 SR |
5774 | struct dentry *trace_instance_dir; |
5775 | ||
5776 | static void | |
5777 | init_tracer_debugfs(struct trace_array *tr, struct dentry *d_tracer); | |
5778 | ||
737223fb SRRH |
5779 | static void init_trace_buffers(struct trace_array *tr, struct trace_buffer *buf) |
5780 | { | |
5781 | int cpu; | |
5782 | ||
5783 | for_each_tracing_cpu(cpu) { | |
5784 | memset(per_cpu_ptr(buf->data, cpu), 0, sizeof(struct trace_array_cpu)); | |
5785 | per_cpu_ptr(buf->data, cpu)->trace_cpu.cpu = cpu; | |
5786 | per_cpu_ptr(buf->data, cpu)->trace_cpu.tr = tr; | |
5787 | } | |
5788 | } | |
5789 | ||
55034cd6 SRRH |
5790 | static int |
5791 | allocate_trace_buffer(struct trace_array *tr, struct trace_buffer *buf, int size) | |
277ba044 SR |
5792 | { |
5793 | enum ring_buffer_flags rb_flags; | |
737223fb SRRH |
5794 | |
5795 | rb_flags = trace_flags & TRACE_ITER_OVERWRITE ? RB_FL_OVERWRITE : 0; | |
5796 | ||
55034cd6 SRRH |
5797 | buf->buffer = ring_buffer_alloc(size, rb_flags); |
5798 | if (!buf->buffer) | |
5799 | return -ENOMEM; | |
737223fb | 5800 | |
55034cd6 SRRH |
5801 | buf->data = alloc_percpu(struct trace_array_cpu); |
5802 | if (!buf->data) { | |
5803 | ring_buffer_free(buf->buffer); | |
5804 | return -ENOMEM; | |
5805 | } | |
737223fb | 5806 | |
55034cd6 | 5807 | init_trace_buffers(tr, buf); |
737223fb SRRH |
5808 | |
5809 | /* Allocate the first page for all buffers */ | |
5810 | set_buffer_entries(&tr->trace_buffer, | |
5811 | ring_buffer_size(tr->trace_buffer.buffer, 0)); | |
5812 | ||
55034cd6 SRRH |
5813 | return 0; |
5814 | } | |
737223fb | 5815 | |
55034cd6 SRRH |
5816 | static int allocate_trace_buffers(struct trace_array *tr, int size) |
5817 | { | |
5818 | int ret; | |
737223fb | 5819 | |
55034cd6 SRRH |
5820 | ret = allocate_trace_buffer(tr, &tr->trace_buffer, size); |
5821 | if (ret) | |
5822 | return ret; | |
737223fb | 5823 | |
55034cd6 SRRH |
5824 | #ifdef CONFIG_TRACER_MAX_TRACE |
5825 | ret = allocate_trace_buffer(tr, &tr->max_buffer, | |
5826 | allocate_snapshot ? size : 1); | |
5827 | if (WARN_ON(ret)) { | |
737223fb | 5828 | ring_buffer_free(tr->trace_buffer.buffer); |
55034cd6 SRRH |
5829 | free_percpu(tr->trace_buffer.data); |
5830 | return -ENOMEM; | |
5831 | } | |
5832 | tr->allocated_snapshot = allocate_snapshot; | |
737223fb | 5833 | |
55034cd6 SRRH |
5834 | /* |
5835 | * Only the top level trace array gets its snapshot allocated | |
5836 | * from the kernel command line. | |
5837 | */ | |
5838 | allocate_snapshot = false; | |
737223fb | 5839 | #endif |
55034cd6 | 5840 | return 0; |
737223fb SRRH |
5841 | } |
5842 | ||
5843 | static int new_instance_create(const char *name) | |
5844 | { | |
277ba044 SR |
5845 | struct trace_array *tr; |
5846 | int ret; | |
277ba044 SR |
5847 | |
5848 | mutex_lock(&trace_types_lock); | |
5849 | ||
5850 | ret = -EEXIST; | |
5851 | list_for_each_entry(tr, &ftrace_trace_arrays, list) { | |
5852 | if (tr->name && strcmp(tr->name, name) == 0) | |
5853 | goto out_unlock; | |
5854 | } | |
5855 | ||
5856 | ret = -ENOMEM; | |
5857 | tr = kzalloc(sizeof(*tr), GFP_KERNEL); | |
5858 | if (!tr) | |
5859 | goto out_unlock; | |
5860 | ||
5861 | tr->name = kstrdup(name, GFP_KERNEL); | |
5862 | if (!tr->name) | |
5863 | goto out_free_tr; | |
5864 | ||
5865 | raw_spin_lock_init(&tr->start_lock); | |
5866 | ||
5867 | tr->current_trace = &nop_trace; | |
5868 | ||
5869 | INIT_LIST_HEAD(&tr->systems); | |
5870 | INIT_LIST_HEAD(&tr->events); | |
5871 | ||
737223fb | 5872 | if (allocate_trace_buffers(tr, trace_buf_size) < 0) |
277ba044 SR |
5873 | goto out_free_tr; |
5874 | ||
277ba044 SR |
5875 | /* Holder for file callbacks */ |
5876 | tr->trace_cpu.cpu = RING_BUFFER_ALL_CPUS; | |
5877 | tr->trace_cpu.tr = tr; | |
5878 | ||
5879 | tr->dir = debugfs_create_dir(name, trace_instance_dir); | |
5880 | if (!tr->dir) | |
5881 | goto out_free_tr; | |
5882 | ||
5883 | ret = event_trace_add_tracer(tr->dir, tr); | |
5884 | if (ret) | |
5885 | goto out_free_tr; | |
5886 | ||
5887 | init_tracer_debugfs(tr, tr->dir); | |
5888 | ||
5889 | list_add(&tr->list, &ftrace_trace_arrays); | |
5890 | ||
5891 | mutex_unlock(&trace_types_lock); | |
5892 | ||
5893 | return 0; | |
5894 | ||
5895 | out_free_tr: | |
12883efb SRRH |
5896 | if (tr->trace_buffer.buffer) |
5897 | ring_buffer_free(tr->trace_buffer.buffer); | |
277ba044 SR |
5898 | kfree(tr->name); |
5899 | kfree(tr); | |
5900 | ||
5901 | out_unlock: | |
5902 | mutex_unlock(&trace_types_lock); | |
5903 | ||
5904 | return ret; | |
5905 | ||
5906 | } | |
5907 | ||
0c8916c3 SR |
5908 | static int instance_delete(const char *name) |
5909 | { | |
5910 | struct trace_array *tr; | |
5911 | int found = 0; | |
5912 | int ret; | |
5913 | ||
5914 | mutex_lock(&trace_types_lock); | |
5915 | ||
5916 | ret = -ENODEV; | |
5917 | list_for_each_entry(tr, &ftrace_trace_arrays, list) { | |
5918 | if (tr->name && strcmp(tr->name, name) == 0) { | |
5919 | found = 1; | |
5920 | break; | |
5921 | } | |
5922 | } | |
5923 | if (!found) | |
5924 | goto out_unlock; | |
5925 | ||
a695cb58 SRRH |
5926 | ret = -EBUSY; |
5927 | if (tr->ref) | |
5928 | goto out_unlock; | |
5929 | ||
0c8916c3 SR |
5930 | list_del(&tr->list); |
5931 | ||
5932 | event_trace_del_tracer(tr); | |
5933 | debugfs_remove_recursive(tr->dir); | |
12883efb SRRH |
5934 | free_percpu(tr->trace_buffer.data); |
5935 | ring_buffer_free(tr->trace_buffer.buffer); | |
0c8916c3 SR |
5936 | |
5937 | kfree(tr->name); | |
5938 | kfree(tr); | |
5939 | ||
5940 | ret = 0; | |
5941 | ||
5942 | out_unlock: | |
5943 | mutex_unlock(&trace_types_lock); | |
5944 | ||
5945 | return ret; | |
5946 | } | |
5947 | ||
277ba044 SR |
5948 | static int instance_mkdir (struct inode *inode, struct dentry *dentry, umode_t mode) |
5949 | { | |
5950 | struct dentry *parent; | |
5951 | int ret; | |
5952 | ||
5953 | /* Paranoid: Make sure the parent is the "instances" directory */ | |
5954 | parent = hlist_entry(inode->i_dentry.first, struct dentry, d_alias); | |
5955 | if (WARN_ON_ONCE(parent != trace_instance_dir)) | |
5956 | return -ENOENT; | |
5957 | ||
5958 | /* | |
5959 | * The inode mutex is locked, but debugfs_create_dir() will also | |
5960 | * take the mutex. As the instances directory can not be destroyed | |
5961 | * or changed in any other way, it is safe to unlock it, and | |
5962 | * let the dentry try. If two users try to make the same dir at | |
5963 | * the same time, then the new_instance_create() will determine the | |
5964 | * winner. | |
5965 | */ | |
5966 | mutex_unlock(&inode->i_mutex); | |
5967 | ||
5968 | ret = new_instance_create(dentry->d_iname); | |
5969 | ||
5970 | mutex_lock(&inode->i_mutex); | |
5971 | ||
5972 | return ret; | |
5973 | } | |
5974 | ||
0c8916c3 SR |
5975 | static int instance_rmdir(struct inode *inode, struct dentry *dentry) |
5976 | { | |
5977 | struct dentry *parent; | |
5978 | int ret; | |
5979 | ||
5980 | /* Paranoid: Make sure the parent is the "instances" directory */ | |
5981 | parent = hlist_entry(inode->i_dentry.first, struct dentry, d_alias); | |
5982 | if (WARN_ON_ONCE(parent != trace_instance_dir)) | |
5983 | return -ENOENT; | |
5984 | ||
5985 | /* The caller did a dget() on dentry */ | |
5986 | mutex_unlock(&dentry->d_inode->i_mutex); | |
5987 | ||
5988 | /* | |
5989 | * The inode mutex is locked, but debugfs_create_dir() will also | |
5990 | * take the mutex. As the instances directory can not be destroyed | |
5991 | * or changed in any other way, it is safe to unlock it, and | |
5992 | * let the dentry try. If two users try to make the same dir at | |
5993 | * the same time, then the instance_delete() will determine the | |
5994 | * winner. | |
5995 | */ | |
5996 | mutex_unlock(&inode->i_mutex); | |
5997 | ||
5998 | ret = instance_delete(dentry->d_iname); | |
5999 | ||
6000 | mutex_lock_nested(&inode->i_mutex, I_MUTEX_PARENT); | |
6001 | mutex_lock(&dentry->d_inode->i_mutex); | |
6002 | ||
6003 | return ret; | |
6004 | } | |
6005 | ||
277ba044 SR |
6006 | static const struct inode_operations instance_dir_inode_operations = { |
6007 | .lookup = simple_lookup, | |
6008 | .mkdir = instance_mkdir, | |
0c8916c3 | 6009 | .rmdir = instance_rmdir, |
277ba044 SR |
6010 | }; |
6011 | ||
6012 | static __init void create_trace_instances(struct dentry *d_tracer) | |
6013 | { | |
6014 | trace_instance_dir = debugfs_create_dir("instances", d_tracer); | |
6015 | if (WARN_ON(!trace_instance_dir)) | |
6016 | return; | |
6017 | ||
6018 | /* Hijack the dir inode operations, to allow mkdir */ | |
6019 | trace_instance_dir->d_inode->i_op = &instance_dir_inode_operations; | |
6020 | } | |
6021 | ||
2b6080f2 SR |
6022 | static void |
6023 | init_tracer_debugfs(struct trace_array *tr, struct dentry *d_tracer) | |
6024 | { | |
121aaee7 | 6025 | int cpu; |
2b6080f2 SR |
6026 | |
6027 | trace_create_file("trace_options", 0644, d_tracer, | |
6028 | tr, &tracing_iter_fops); | |
6029 | ||
6030 | trace_create_file("trace", 0644, d_tracer, | |
6031 | (void *)&tr->trace_cpu, &tracing_fops); | |
6032 | ||
6033 | trace_create_file("trace_pipe", 0444, d_tracer, | |
6034 | (void *)&tr->trace_cpu, &tracing_pipe_fops); | |
6035 | ||
6036 | trace_create_file("buffer_size_kb", 0644, d_tracer, | |
6037 | (void *)&tr->trace_cpu, &tracing_entries_fops); | |
6038 | ||
6039 | trace_create_file("buffer_total_size_kb", 0444, d_tracer, | |
6040 | tr, &tracing_total_entries_fops); | |
6041 | ||
238ae93d | 6042 | trace_create_file("free_buffer", 0200, d_tracer, |
2b6080f2 SR |
6043 | tr, &tracing_free_buffer_fops); |
6044 | ||
6045 | trace_create_file("trace_marker", 0220, d_tracer, | |
6046 | tr, &tracing_mark_fops); | |
6047 | ||
6048 | trace_create_file("trace_clock", 0644, d_tracer, tr, | |
6049 | &trace_clock_fops); | |
6050 | ||
6051 | trace_create_file("tracing_on", 0644, d_tracer, | |
6052 | tr, &rb_simple_fops); | |
ce9bae55 SRRH |
6053 | |
6054 | #ifdef CONFIG_TRACER_SNAPSHOT | |
6055 | trace_create_file("snapshot", 0644, d_tracer, | |
6056 | (void *)&tr->trace_cpu, &snapshot_fops); | |
6057 | #endif | |
121aaee7 SRRH |
6058 | |
6059 | for_each_tracing_cpu(cpu) | |
6060 | tracing_init_debugfs_percpu(tr, cpu); | |
6061 | ||
2b6080f2 SR |
6062 | } |
6063 | ||
b5ad384e | 6064 | static __init int tracer_init_debugfs(void) |
bc0c38d1 SR |
6065 | { |
6066 | struct dentry *d_tracer; | |
bc0c38d1 | 6067 | |
7e53bd42 LJ |
6068 | trace_access_lock_init(); |
6069 | ||
bc0c38d1 | 6070 | d_tracer = tracing_init_dentry(); |
ed6f1c99 NK |
6071 | if (!d_tracer) |
6072 | return 0; | |
bc0c38d1 | 6073 | |
2b6080f2 | 6074 | init_tracer_debugfs(&global_trace, d_tracer); |
bc0c38d1 | 6075 | |
5452af66 | 6076 | trace_create_file("tracing_cpumask", 0644, d_tracer, |
2b6080f2 | 6077 | &global_trace, &tracing_cpumask_fops); |
a8259075 | 6078 | |
5452af66 FW |
6079 | trace_create_file("available_tracers", 0444, d_tracer, |
6080 | &global_trace, &show_traces_fops); | |
6081 | ||
339ae5d3 | 6082 | trace_create_file("current_tracer", 0644, d_tracer, |
5452af66 FW |
6083 | &global_trace, &set_tracer_fops); |
6084 | ||
5d4a9dba | 6085 | #ifdef CONFIG_TRACER_MAX_TRACE |
5452af66 FW |
6086 | trace_create_file("tracing_max_latency", 0644, d_tracer, |
6087 | &tracing_max_latency, &tracing_max_lat_fops); | |
0e950173 | 6088 | #endif |
5452af66 FW |
6089 | |
6090 | trace_create_file("tracing_thresh", 0644, d_tracer, | |
6091 | &tracing_thresh, &tracing_max_lat_fops); | |
a8259075 | 6092 | |
339ae5d3 | 6093 | trace_create_file("README", 0444, d_tracer, |
5452af66 FW |
6094 | NULL, &tracing_readme_fops); |
6095 | ||
69abe6a5 AP |
6096 | trace_create_file("saved_cmdlines", 0444, d_tracer, |
6097 | NULL, &tracing_saved_cmdlines_fops); | |
5bf9a1ee | 6098 | |
bc0c38d1 | 6099 | #ifdef CONFIG_DYNAMIC_FTRACE |
5452af66 FW |
6100 | trace_create_file("dyn_ftrace_total_info", 0444, d_tracer, |
6101 | &ftrace_update_tot_cnt, &tracing_dyn_info_fops); | |
bc0c38d1 | 6102 | #endif |
b04cc6b1 | 6103 | |
277ba044 | 6104 | create_trace_instances(d_tracer); |
5452af66 | 6105 | |
2b6080f2 | 6106 | create_trace_options_dir(&global_trace); |
b04cc6b1 | 6107 | |
b5ad384e | 6108 | return 0; |
bc0c38d1 SR |
6109 | } |
6110 | ||
3f5a54e3 SR |
6111 | static int trace_panic_handler(struct notifier_block *this, |
6112 | unsigned long event, void *unused) | |
6113 | { | |
944ac425 | 6114 | if (ftrace_dump_on_oops) |
cecbca96 | 6115 | ftrace_dump(ftrace_dump_on_oops); |
3f5a54e3 SR |
6116 | return NOTIFY_OK; |
6117 | } | |
6118 | ||
6119 | static struct notifier_block trace_panic_notifier = { | |
6120 | .notifier_call = trace_panic_handler, | |
6121 | .next = NULL, | |
6122 | .priority = 150 /* priority: INT_MAX >= x >= 0 */ | |
6123 | }; | |
6124 | ||
6125 | static int trace_die_handler(struct notifier_block *self, | |
6126 | unsigned long val, | |
6127 | void *data) | |
6128 | { | |
6129 | switch (val) { | |
6130 | case DIE_OOPS: | |
944ac425 | 6131 | if (ftrace_dump_on_oops) |
cecbca96 | 6132 | ftrace_dump(ftrace_dump_on_oops); |
3f5a54e3 SR |
6133 | break; |
6134 | default: | |
6135 | break; | |
6136 | } | |
6137 | return NOTIFY_OK; | |
6138 | } | |
6139 | ||
6140 | static struct notifier_block trace_die_notifier = { | |
6141 | .notifier_call = trace_die_handler, | |
6142 | .priority = 200 | |
6143 | }; | |
6144 | ||
6145 | /* | |
6146 | * printk is set to max of 1024, we really don't need it that big. | |
6147 | * Nothing should be printing 1000 characters anyway. | |
6148 | */ | |
6149 | #define TRACE_MAX_PRINT 1000 | |
6150 | ||
6151 | /* | |
6152 | * Define here KERN_TRACE so that we have one place to modify | |
6153 | * it if we decide to change what log level the ftrace dump | |
6154 | * should be at. | |
6155 | */ | |
428aee14 | 6156 | #define KERN_TRACE KERN_EMERG |
3f5a54e3 | 6157 | |
955b61e5 | 6158 | void |
3f5a54e3 SR |
6159 | trace_printk_seq(struct trace_seq *s) |
6160 | { | |
6161 | /* Probably should print a warning here. */ | |
bd6df187 J |
6162 | if (s->len >= TRACE_MAX_PRINT) |
6163 | s->len = TRACE_MAX_PRINT; | |
3f5a54e3 SR |
6164 | |
6165 | /* should be zero ended, but we are paranoid. */ | |
6166 | s->buffer[s->len] = 0; | |
6167 | ||
6168 | printk(KERN_TRACE "%s", s->buffer); | |
6169 | ||
f9520750 | 6170 | trace_seq_init(s); |
3f5a54e3 SR |
6171 | } |
6172 | ||
955b61e5 JW |
6173 | void trace_init_global_iter(struct trace_iterator *iter) |
6174 | { | |
6175 | iter->tr = &global_trace; | |
2b6080f2 | 6176 | iter->trace = iter->tr->current_trace; |
ae3b5093 | 6177 | iter->cpu_file = RING_BUFFER_ALL_CPUS; |
12883efb | 6178 | iter->trace_buffer = &global_trace.trace_buffer; |
955b61e5 JW |
6179 | } |
6180 | ||
7fe70b57 | 6181 | void ftrace_dump(enum ftrace_dump_mode oops_dump_mode) |
3f5a54e3 | 6182 | { |
3f5a54e3 SR |
6183 | /* use static because iter can be a bit big for the stack */ |
6184 | static struct trace_iterator iter; | |
7fe70b57 | 6185 | static atomic_t dump_running; |
cf586b61 | 6186 | unsigned int old_userobj; |
d769041f SR |
6187 | unsigned long flags; |
6188 | int cnt = 0, cpu; | |
3f5a54e3 | 6189 | |
7fe70b57 SRRH |
6190 | /* Only allow one dump user at a time. */ |
6191 | if (atomic_inc_return(&dump_running) != 1) { | |
6192 | atomic_dec(&dump_running); | |
6193 | return; | |
6194 | } | |
3f5a54e3 | 6195 | |
7fe70b57 SRRH |
6196 | /* |
6197 | * Always turn off tracing when we dump. | |
6198 | * We don't need to show trace output of what happens | |
6199 | * between multiple crashes. | |
6200 | * | |
6201 | * If the user does a sysrq-z, then they can re-enable | |
6202 | * tracing with echo 1 > tracing_on. | |
6203 | */ | |
0ee6b6cf | 6204 | tracing_off(); |
cf586b61 | 6205 | |
7fe70b57 | 6206 | local_irq_save(flags); |
3f5a54e3 | 6207 | |
38dbe0b1 | 6208 | /* Simulate the iterator */ |
955b61e5 JW |
6209 | trace_init_global_iter(&iter); |
6210 | ||
d769041f | 6211 | for_each_tracing_cpu(cpu) { |
12883efb | 6212 | atomic_inc(&per_cpu_ptr(iter.tr->trace_buffer.data, cpu)->disabled); |
d769041f SR |
6213 | } |
6214 | ||
cf586b61 FW |
6215 | old_userobj = trace_flags & TRACE_ITER_SYM_USEROBJ; |
6216 | ||
b54d3de9 TE |
6217 | /* don't look at user memory in panic mode */ |
6218 | trace_flags &= ~TRACE_ITER_SYM_USEROBJ; | |
6219 | ||
cecbca96 FW |
6220 | switch (oops_dump_mode) { |
6221 | case DUMP_ALL: | |
ae3b5093 | 6222 | iter.cpu_file = RING_BUFFER_ALL_CPUS; |
cecbca96 FW |
6223 | break; |
6224 | case DUMP_ORIG: | |
6225 | iter.cpu_file = raw_smp_processor_id(); | |
6226 | break; | |
6227 | case DUMP_NONE: | |
6228 | goto out_enable; | |
6229 | default: | |
6230 | printk(KERN_TRACE "Bad dumping mode, switching to all CPUs dump\n"); | |
ae3b5093 | 6231 | iter.cpu_file = RING_BUFFER_ALL_CPUS; |
cecbca96 FW |
6232 | } |
6233 | ||
6234 | printk(KERN_TRACE "Dumping ftrace buffer:\n"); | |
3f5a54e3 | 6235 | |
7fe70b57 SRRH |
6236 | /* Did function tracer already get disabled? */ |
6237 | if (ftrace_is_dead()) { | |
6238 | printk("# WARNING: FUNCTION TRACING IS CORRUPTED\n"); | |
6239 | printk("# MAY BE MISSING FUNCTION EVENTS\n"); | |
6240 | } | |
6241 | ||
3f5a54e3 SR |
6242 | /* |
6243 | * We need to stop all tracing on all CPUS to read the | |
6244 | * the next buffer. This is a bit expensive, but is | |
6245 | * not done often. We fill all what we can read, | |
6246 | * and then release the locks again. | |
6247 | */ | |
6248 | ||
3f5a54e3 SR |
6249 | while (!trace_empty(&iter)) { |
6250 | ||
6251 | if (!cnt) | |
6252 | printk(KERN_TRACE "---------------------------------\n"); | |
6253 | ||
6254 | cnt++; | |
6255 | ||
6256 | /* reset all but tr, trace, and overruns */ | |
6257 | memset(&iter.seq, 0, | |
6258 | sizeof(struct trace_iterator) - | |
6259 | offsetof(struct trace_iterator, seq)); | |
6260 | iter.iter_flags |= TRACE_FILE_LAT_FMT; | |
6261 | iter.pos = -1; | |
6262 | ||
955b61e5 | 6263 | if (trace_find_next_entry_inc(&iter) != NULL) { |
74e7ff8c LJ |
6264 | int ret; |
6265 | ||
6266 | ret = print_trace_line(&iter); | |
6267 | if (ret != TRACE_TYPE_NO_CONSUME) | |
6268 | trace_consume(&iter); | |
3f5a54e3 | 6269 | } |
b892e5c8 | 6270 | touch_nmi_watchdog(); |
3f5a54e3 SR |
6271 | |
6272 | trace_printk_seq(&iter.seq); | |
6273 | } | |
6274 | ||
6275 | if (!cnt) | |
6276 | printk(KERN_TRACE " (ftrace buffer empty)\n"); | |
6277 | else | |
6278 | printk(KERN_TRACE "---------------------------------\n"); | |
6279 | ||
cecbca96 | 6280 | out_enable: |
7fe70b57 | 6281 | trace_flags |= old_userobj; |
cf586b61 | 6282 | |
7fe70b57 SRRH |
6283 | for_each_tracing_cpu(cpu) { |
6284 | atomic_dec(&per_cpu_ptr(iter.trace_buffer->data, cpu)->disabled); | |
cf586b61 | 6285 | } |
7fe70b57 | 6286 | atomic_dec(&dump_running); |
cd891ae0 | 6287 | local_irq_restore(flags); |
3f5a54e3 | 6288 | } |
a8eecf22 | 6289 | EXPORT_SYMBOL_GPL(ftrace_dump); |
cf586b61 | 6290 | |
3928a8a2 | 6291 | __init static int tracer_alloc_buffers(void) |
bc0c38d1 | 6292 | { |
73c5162a | 6293 | int ring_buf_size; |
9e01c1b7 | 6294 | int ret = -ENOMEM; |
4c11d7ae | 6295 | |
750912fa | 6296 | |
9e01c1b7 RR |
6297 | if (!alloc_cpumask_var(&tracing_buffer_mask, GFP_KERNEL)) |
6298 | goto out; | |
6299 | ||
6300 | if (!alloc_cpumask_var(&tracing_cpumask, GFP_KERNEL)) | |
6301 | goto out_free_buffer_mask; | |
4c11d7ae | 6302 | |
07d777fe SR |
6303 | /* Only allocate trace_printk buffers if a trace_printk exists */ |
6304 | if (__stop___trace_bprintk_fmt != __start___trace_bprintk_fmt) | |
81698831 | 6305 | /* Must be called before global_trace.buffer is allocated */ |
07d777fe SR |
6306 | trace_printk_init_buffers(); |
6307 | ||
73c5162a SR |
6308 | /* To save memory, keep the ring buffer size to its minimum */ |
6309 | if (ring_buffer_expanded) | |
6310 | ring_buf_size = trace_buf_size; | |
6311 | else | |
6312 | ring_buf_size = 1; | |
6313 | ||
9e01c1b7 RR |
6314 | cpumask_copy(tracing_buffer_mask, cpu_possible_mask); |
6315 | cpumask_copy(tracing_cpumask, cpu_all_mask); | |
6316 | ||
2b6080f2 SR |
6317 | raw_spin_lock_init(&global_trace.start_lock); |
6318 | ||
9e01c1b7 | 6319 | /* TODO: make the number of buffers hot pluggable with CPUS */ |
737223fb | 6320 | if (allocate_trace_buffers(&global_trace, ring_buf_size) < 0) { |
3928a8a2 SR |
6321 | printk(KERN_ERR "tracer: failed to allocate ring buffer!\n"); |
6322 | WARN_ON(1); | |
9e01c1b7 | 6323 | goto out_free_cpumask; |
4c11d7ae | 6324 | } |
a7603ff4 | 6325 | |
499e5470 SR |
6326 | if (global_trace.buffer_disabled) |
6327 | tracing_off(); | |
4c11d7ae | 6328 | |
bc0c38d1 SR |
6329 | trace_init_cmdlines(); |
6330 | ||
ca164318 SRRH |
6331 | /* |
6332 | * register_tracer() might reference current_trace, so it | |
6333 | * needs to be set before we register anything. This is | |
6334 | * just a bootstrap of current_trace anyway. | |
6335 | */ | |
2b6080f2 SR |
6336 | global_trace.current_trace = &nop_trace; |
6337 | ||
ca164318 SRRH |
6338 | register_tracer(&nop_trace); |
6339 | ||
60a11774 SR |
6340 | /* All seems OK, enable tracing */ |
6341 | tracing_disabled = 0; | |
3928a8a2 | 6342 | |
3f5a54e3 SR |
6343 | atomic_notifier_chain_register(&panic_notifier_list, |
6344 | &trace_panic_notifier); | |
6345 | ||
6346 | register_die_notifier(&trace_die_notifier); | |
2fc1dfbe | 6347 | |
ae63b31e SR |
6348 | global_trace.flags = TRACE_ARRAY_FL_GLOBAL; |
6349 | ||
2b6080f2 SR |
6350 | /* Holder for file callbacks */ |
6351 | global_trace.trace_cpu.cpu = RING_BUFFER_ALL_CPUS; | |
6352 | global_trace.trace_cpu.tr = &global_trace; | |
6353 | ||
ae63b31e SR |
6354 | INIT_LIST_HEAD(&global_trace.systems); |
6355 | INIT_LIST_HEAD(&global_trace.events); | |
6356 | list_add(&global_trace.list, &ftrace_trace_arrays); | |
6357 | ||
7bcfaf54 SR |
6358 | while (trace_boot_options) { |
6359 | char *option; | |
6360 | ||
6361 | option = strsep(&trace_boot_options, ","); | |
2b6080f2 | 6362 | trace_set_options(&global_trace, option); |
7bcfaf54 SR |
6363 | } |
6364 | ||
77fd5c15 SRRH |
6365 | register_snapshot_cmd(); |
6366 | ||
2fc1dfbe | 6367 | return 0; |
3f5a54e3 | 6368 | |
9e01c1b7 | 6369 | out_free_cpumask: |
12883efb SRRH |
6370 | free_percpu(global_trace.trace_buffer.data); |
6371 | #ifdef CONFIG_TRACER_MAX_TRACE | |
6372 | free_percpu(global_trace.max_buffer.data); | |
6373 | #endif | |
9e01c1b7 RR |
6374 | free_cpumask_var(tracing_cpumask); |
6375 | out_free_buffer_mask: | |
6376 | free_cpumask_var(tracing_buffer_mask); | |
6377 | out: | |
6378 | return ret; | |
bc0c38d1 | 6379 | } |
b2821ae6 SR |
6380 | |
6381 | __init static int clear_boot_tracer(void) | |
6382 | { | |
6383 | /* | |
6384 | * The default tracer at boot buffer is an init section. | |
6385 | * This function is called in lateinit. If we did not | |
6386 | * find the boot tracer, then clear it out, to prevent | |
6387 | * later registration from accessing the buffer that is | |
6388 | * about to be freed. | |
6389 | */ | |
6390 | if (!default_bootup_tracer) | |
6391 | return 0; | |
6392 | ||
6393 | printk(KERN_INFO "ftrace bootup tracer '%s' not registered.\n", | |
6394 | default_bootup_tracer); | |
6395 | default_bootup_tracer = NULL; | |
6396 | ||
6397 | return 0; | |
6398 | } | |
6399 | ||
b5ad384e FW |
6400 | early_initcall(tracer_alloc_buffers); |
6401 | fs_initcall(tracer_init_debugfs); | |
b2821ae6 | 6402 | late_initcall(clear_boot_tracer); |