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 | |
b2821ae6 SR |
118 | static int tracing_set_tracer(const char *buf); |
119 | ||
ee6c2c1b LZ |
120 | #define MAX_TRACER_SIZE 100 |
121 | static char bootup_tracer_buf[MAX_TRACER_SIZE] __initdata; | |
b2821ae6 | 122 | static char *default_bootup_tracer; |
d9e54076 | 123 | |
55034cd6 SRRH |
124 | static bool allocate_snapshot; |
125 | ||
1beee96b | 126 | static int __init set_cmdline_ftrace(char *str) |
d9e54076 | 127 | { |
67012ab1 | 128 | strlcpy(bootup_tracer_buf, str, MAX_TRACER_SIZE); |
b2821ae6 | 129 | default_bootup_tracer = bootup_tracer_buf; |
73c5162a | 130 | /* We are using ftrace early, expand it */ |
55034cd6 | 131 | ring_buffer_expanded = true; |
d9e54076 PZ |
132 | return 1; |
133 | } | |
1beee96b | 134 | __setup("ftrace=", set_cmdline_ftrace); |
d9e54076 | 135 | |
944ac425 SR |
136 | static int __init set_ftrace_dump_on_oops(char *str) |
137 | { | |
cecbca96 FW |
138 | if (*str++ != '=' || !*str) { |
139 | ftrace_dump_on_oops = DUMP_ALL; | |
140 | return 1; | |
141 | } | |
142 | ||
143 | if (!strcmp("orig_cpu", str)) { | |
144 | ftrace_dump_on_oops = DUMP_ORIG; | |
145 | return 1; | |
146 | } | |
147 | ||
148 | return 0; | |
944ac425 SR |
149 | } |
150 | __setup("ftrace_dump_on_oops", set_ftrace_dump_on_oops); | |
60a11774 | 151 | |
3209cff4 | 152 | static int __init boot_alloc_snapshot(char *str) |
55034cd6 SRRH |
153 | { |
154 | allocate_snapshot = true; | |
155 | /* We also need the main ring buffer expanded */ | |
156 | ring_buffer_expanded = true; | |
157 | return 1; | |
158 | } | |
3209cff4 | 159 | __setup("alloc_snapshot", boot_alloc_snapshot); |
55034cd6 | 160 | |
7bcfaf54 SR |
161 | |
162 | static char trace_boot_options_buf[MAX_TRACER_SIZE] __initdata; | |
163 | static char *trace_boot_options __initdata; | |
164 | ||
165 | static int __init set_trace_boot_options(char *str) | |
166 | { | |
67012ab1 | 167 | strlcpy(trace_boot_options_buf, str, MAX_TRACER_SIZE); |
7bcfaf54 SR |
168 | trace_boot_options = trace_boot_options_buf; |
169 | return 0; | |
170 | } | |
171 | __setup("trace_options=", set_trace_boot_options); | |
172 | ||
cf8e3474 | 173 | unsigned long long ns2usecs(cycle_t nsec) |
bc0c38d1 SR |
174 | { |
175 | nsec += 500; | |
176 | do_div(nsec, 1000); | |
177 | return nsec; | |
178 | } | |
179 | ||
4fcdae83 SR |
180 | /* |
181 | * The global_trace is the descriptor that holds the tracing | |
182 | * buffers for the live tracing. For each CPU, it contains | |
183 | * a link list of pages that will store trace entries. The | |
184 | * page descriptor of the pages in the memory is used to hold | |
185 | * the link list by linking the lru item in the page descriptor | |
186 | * to each of the pages in the buffer per CPU. | |
187 | * | |
188 | * For each active CPU there is a data field that holds the | |
189 | * pages for the buffer for that CPU. Each CPU has the same number | |
190 | * of pages allocated for its buffer. | |
191 | */ | |
bc0c38d1 SR |
192 | static struct trace_array global_trace; |
193 | ||
ae63b31e | 194 | LIST_HEAD(ftrace_trace_arrays); |
bc0c38d1 | 195 | |
59d8f488 SRRH |
196 | int trace_array_get(struct trace_array *this_tr) |
197 | { | |
198 | struct trace_array *tr; | |
199 | int ret = -ENODEV; | |
200 | ||
201 | mutex_lock(&trace_types_lock); | |
202 | list_for_each_entry(tr, &ftrace_trace_arrays, list) { | |
203 | if (tr == this_tr) { | |
204 | tr->ref++; | |
205 | ret = 0; | |
206 | break; | |
207 | } | |
208 | } | |
209 | mutex_unlock(&trace_types_lock); | |
210 | ||
211 | return ret; | |
212 | } | |
213 | ||
214 | static void __trace_array_put(struct trace_array *this_tr) | |
215 | { | |
216 | WARN_ON(!this_tr->ref); | |
217 | this_tr->ref--; | |
218 | } | |
219 | ||
220 | void trace_array_put(struct trace_array *this_tr) | |
221 | { | |
222 | mutex_lock(&trace_types_lock); | |
223 | __trace_array_put(this_tr); | |
224 | mutex_unlock(&trace_types_lock); | |
225 | } | |
226 | ||
e77405ad SR |
227 | int filter_current_check_discard(struct ring_buffer *buffer, |
228 | struct ftrace_event_call *call, void *rec, | |
eb02ce01 TZ |
229 | struct ring_buffer_event *event) |
230 | { | |
e77405ad | 231 | return filter_check_discard(call, rec, buffer, event); |
eb02ce01 | 232 | } |
17c873ec | 233 | EXPORT_SYMBOL_GPL(filter_current_check_discard); |
eb02ce01 | 234 | |
e88512e7 | 235 | cycle_t buffer_ftrace_now(struct trace_buffer *buf, int cpu) |
37886f6a SR |
236 | { |
237 | u64 ts; | |
238 | ||
239 | /* Early boot up does not have a buffer yet */ | |
e88512e7 | 240 | if (!buf->buffer) |
37886f6a SR |
241 | return trace_clock_local(); |
242 | ||
e88512e7 AL |
243 | ts = ring_buffer_time_stamp(buf->buffer, cpu); |
244 | ring_buffer_normalize_time_stamp(buf->buffer, cpu, &ts); | |
37886f6a SR |
245 | |
246 | return ts; | |
247 | } | |
bc0c38d1 | 248 | |
e88512e7 AL |
249 | cycle_t ftrace_now(int cpu) |
250 | { | |
251 | return buffer_ftrace_now(&global_trace.trace_buffer, cpu); | |
252 | } | |
253 | ||
2fd821ee SRRH |
254 | /** |
255 | * tracing_is_enabled - Show if global_trace has been disabled | |
256 | * | |
257 | * Shows if the global trace has been enabled or not. It uses the | |
258 | * mirror flag "buffer_disabled" to be used in fast paths such as for | |
259 | * the irqsoff tracer. But it may be inaccurate due to races. If you | |
260 | * need to know the accurate state, use tracing_is_on() which is a little | |
261 | * slower, but accurate. | |
262 | */ | |
9036990d SR |
263 | int tracing_is_enabled(void) |
264 | { | |
2fd821ee SRRH |
265 | /* |
266 | * For quick access (irqsoff uses this in fast path), just | |
267 | * return the mirror variable of the state of the ring buffer. | |
268 | * It's a little racy, but we don't really care. | |
269 | */ | |
270 | smp_rmb(); | |
271 | return !global_trace.buffer_disabled; | |
9036990d SR |
272 | } |
273 | ||
4fcdae83 | 274 | /* |
3928a8a2 SR |
275 | * trace_buf_size is the size in bytes that is allocated |
276 | * for a buffer. Note, the number of bytes is always rounded | |
277 | * to page size. | |
3f5a54e3 SR |
278 | * |
279 | * This number is purposely set to a low number of 16384. | |
280 | * If the dump on oops happens, it will be much appreciated | |
281 | * to not have to wait for all that output. Anyway this can be | |
282 | * boot time and run time configurable. | |
4fcdae83 | 283 | */ |
3928a8a2 | 284 | #define TRACE_BUF_SIZE_DEFAULT 1441792UL /* 16384 * 88 (sizeof(entry)) */ |
3f5a54e3 | 285 | |
3928a8a2 | 286 | static unsigned long trace_buf_size = TRACE_BUF_SIZE_DEFAULT; |
bc0c38d1 | 287 | |
4fcdae83 | 288 | /* trace_types holds a link list of available tracers. */ |
bc0c38d1 | 289 | static struct tracer *trace_types __read_mostly; |
4fcdae83 | 290 | |
4fcdae83 SR |
291 | /* |
292 | * trace_types_lock is used to protect the trace_types list. | |
4fcdae83 | 293 | */ |
9713f785 | 294 | DEFINE_MUTEX(trace_types_lock); |
4fcdae83 | 295 | |
7e53bd42 LJ |
296 | /* |
297 | * serialize the access of the ring buffer | |
298 | * | |
299 | * ring buffer serializes readers, but it is low level protection. | |
300 | * The validity of the events (which returns by ring_buffer_peek() ..etc) | |
301 | * are not protected by ring buffer. | |
302 | * | |
303 | * The content of events may become garbage if we allow other process consumes | |
304 | * these events concurrently: | |
305 | * A) the page of the consumed events may become a normal page | |
306 | * (not reader page) in ring buffer, and this page will be rewrited | |
307 | * by events producer. | |
308 | * B) The page of the consumed events may become a page for splice_read, | |
309 | * and this page will be returned to system. | |
310 | * | |
311 | * These primitives allow multi process access to different cpu ring buffer | |
312 | * concurrently. | |
313 | * | |
314 | * These primitives don't distinguish read-only and read-consume access. | |
315 | * Multi read-only access are also serialized. | |
316 | */ | |
317 | ||
318 | #ifdef CONFIG_SMP | |
319 | static DECLARE_RWSEM(all_cpu_access_lock); | |
320 | static DEFINE_PER_CPU(struct mutex, cpu_access_lock); | |
321 | ||
322 | static inline void trace_access_lock(int cpu) | |
323 | { | |
ae3b5093 | 324 | if (cpu == RING_BUFFER_ALL_CPUS) { |
7e53bd42 LJ |
325 | /* gain it for accessing the whole ring buffer. */ |
326 | down_write(&all_cpu_access_lock); | |
327 | } else { | |
328 | /* gain it for accessing a cpu ring buffer. */ | |
329 | ||
ae3b5093 | 330 | /* Firstly block other trace_access_lock(RING_BUFFER_ALL_CPUS). */ |
7e53bd42 LJ |
331 | down_read(&all_cpu_access_lock); |
332 | ||
333 | /* Secondly block other access to this @cpu ring buffer. */ | |
334 | mutex_lock(&per_cpu(cpu_access_lock, cpu)); | |
335 | } | |
336 | } | |
337 | ||
338 | static inline void trace_access_unlock(int cpu) | |
339 | { | |
ae3b5093 | 340 | if (cpu == RING_BUFFER_ALL_CPUS) { |
7e53bd42 LJ |
341 | up_write(&all_cpu_access_lock); |
342 | } else { | |
343 | mutex_unlock(&per_cpu(cpu_access_lock, cpu)); | |
344 | up_read(&all_cpu_access_lock); | |
345 | } | |
346 | } | |
347 | ||
348 | static inline void trace_access_lock_init(void) | |
349 | { | |
350 | int cpu; | |
351 | ||
352 | for_each_possible_cpu(cpu) | |
353 | mutex_init(&per_cpu(cpu_access_lock, cpu)); | |
354 | } | |
355 | ||
356 | #else | |
357 | ||
358 | static DEFINE_MUTEX(access_lock); | |
359 | ||
360 | static inline void trace_access_lock(int cpu) | |
361 | { | |
362 | (void)cpu; | |
363 | mutex_lock(&access_lock); | |
364 | } | |
365 | ||
366 | static inline void trace_access_unlock(int cpu) | |
367 | { | |
368 | (void)cpu; | |
369 | mutex_unlock(&access_lock); | |
370 | } | |
371 | ||
372 | static inline void trace_access_lock_init(void) | |
373 | { | |
374 | } | |
375 | ||
376 | #endif | |
377 | ||
ee6bce52 | 378 | /* trace_flags holds trace_options default values */ |
12ef7d44 | 379 | unsigned long trace_flags = TRACE_ITER_PRINT_PARENT | TRACE_ITER_PRINTK | |
a2a16d6a | 380 | TRACE_ITER_ANNOTATE | TRACE_ITER_CONTEXT_INFO | TRACE_ITER_SLEEP_TIME | |
77271ce4 | 381 | TRACE_ITER_GRAPH_TIME | TRACE_ITER_RECORD_CMD | TRACE_ITER_OVERWRITE | |
328df475 | 382 | TRACE_ITER_IRQ_INFO | TRACE_ITER_MARKERS | TRACE_ITER_FUNCTION; |
e7e2ee89 | 383 | |
2fd821ee SRRH |
384 | void tracer_tracing_on(struct trace_array *tr) |
385 | { | |
386 | if (tr->trace_buffer.buffer) | |
387 | ring_buffer_record_on(tr->trace_buffer.buffer); | |
388 | /* | |
389 | * This flag is looked at when buffers haven't been allocated | |
390 | * yet, or by some tracers (like irqsoff), that just want to | |
391 | * know if the ring buffer has been disabled, but it can handle | |
392 | * races of where it gets disabled but we still do a record. | |
393 | * As the check is in the fast path of the tracers, it is more | |
394 | * important to be fast than accurate. | |
395 | */ | |
396 | tr->buffer_disabled = 0; | |
397 | /* Make the flag seen by readers */ | |
398 | smp_wmb(); | |
399 | } | |
400 | ||
499e5470 SR |
401 | /** |
402 | * tracing_on - enable tracing buffers | |
403 | * | |
404 | * This function enables tracing buffers that may have been | |
405 | * disabled with tracing_off. | |
406 | */ | |
407 | void tracing_on(void) | |
408 | { | |
2fd821ee | 409 | tracer_tracing_on(&global_trace); |
499e5470 SR |
410 | } |
411 | EXPORT_SYMBOL_GPL(tracing_on); | |
412 | ||
09ae7234 SRRH |
413 | /** |
414 | * __trace_puts - write a constant string into the trace buffer. | |
415 | * @ip: The address of the caller | |
416 | * @str: The constant string to write | |
417 | * @size: The size of the string. | |
418 | */ | |
419 | int __trace_puts(unsigned long ip, const char *str, int size) | |
420 | { | |
421 | struct ring_buffer_event *event; | |
422 | struct ring_buffer *buffer; | |
423 | struct print_entry *entry; | |
424 | unsigned long irq_flags; | |
425 | int alloc; | |
e250100b J |
426 | int pc; |
427 | ||
428 | pc = preempt_count(); | |
09ae7234 | 429 | |
f74bb740 SRRH |
430 | if (unlikely(tracing_selftest_running || tracing_disabled)) |
431 | return 0; | |
432 | ||
09ae7234 SRRH |
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, | |
e250100b | 438 | irq_flags, pc); |
09ae7234 SRRH |
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); | |
e250100b | 455 | ftrace_trace_stack(buffer, irq_flags, 4, pc); |
09ae7234 SRRH |
456 | |
457 | return size; | |
458 | } | |
459 | EXPORT_SYMBOL_GPL(__trace_puts); | |
460 | ||
461 | /** | |
462 | * __trace_bputs - write the pointer to a constant string into trace buffer | |
463 | * @ip: The address of the caller | |
464 | * @str: The constant string to write to the buffer to | |
465 | */ | |
466 | int __trace_bputs(unsigned long ip, const char *str) | |
467 | { | |
468 | struct ring_buffer_event *event; | |
469 | struct ring_buffer *buffer; | |
470 | struct bputs_entry *entry; | |
471 | unsigned long irq_flags; | |
472 | int size = sizeof(struct bputs_entry); | |
e250100b J |
473 | int pc; |
474 | ||
475 | pc = preempt_count(); | |
09ae7234 | 476 | |
f74bb740 SRRH |
477 | if (unlikely(tracing_selftest_running || tracing_disabled)) |
478 | return 0; | |
479 | ||
09ae7234 SRRH |
480 | local_save_flags(irq_flags); |
481 | buffer = global_trace.trace_buffer.buffer; | |
482 | event = trace_buffer_lock_reserve(buffer, TRACE_BPUTS, size, | |
e250100b | 483 | irq_flags, pc); |
09ae7234 SRRH |
484 | if (!event) |
485 | return 0; | |
486 | ||
487 | entry = ring_buffer_event_data(event); | |
488 | entry->ip = ip; | |
489 | entry->str = str; | |
490 | ||
491 | __buffer_unlock_commit(buffer, event); | |
e250100b | 492 | ftrace_trace_stack(buffer, irq_flags, 4, pc); |
09ae7234 SRRH |
493 | |
494 | return 1; | |
495 | } | |
496 | EXPORT_SYMBOL_GPL(__trace_bputs); | |
497 | ||
ad909e21 SRRH |
498 | #ifdef CONFIG_TRACER_SNAPSHOT |
499 | /** | |
500 | * trace_snapshot - take a snapshot of the current buffer. | |
501 | * | |
502 | * This causes a swap between the snapshot buffer and the current live | |
503 | * tracing buffer. You can use this to take snapshots of the live | |
504 | * trace when some condition is triggered, but continue to trace. | |
505 | * | |
506 | * Note, make sure to allocate the snapshot with either | |
507 | * a tracing_snapshot_alloc(), or by doing it manually | |
508 | * with: echo 1 > /sys/kernel/debug/tracing/snapshot | |
509 | * | |
510 | * If the snapshot buffer is not allocated, it will stop tracing. | |
511 | * Basically making a permanent snapshot. | |
512 | */ | |
513 | void tracing_snapshot(void) | |
514 | { | |
515 | struct trace_array *tr = &global_trace; | |
516 | struct tracer *tracer = tr->current_trace; | |
517 | unsigned long flags; | |
518 | ||
1b22e382 SRRH |
519 | if (in_nmi()) { |
520 | internal_trace_puts("*** SNAPSHOT CALLED FROM NMI CONTEXT ***\n"); | |
521 | internal_trace_puts("*** snapshot is being ignored ***\n"); | |
522 | return; | |
523 | } | |
524 | ||
ad909e21 | 525 | if (!tr->allocated_snapshot) { |
ca268da6 SRRH |
526 | internal_trace_puts("*** SNAPSHOT NOT ALLOCATED ***\n"); |
527 | internal_trace_puts("*** stopping trace here! ***\n"); | |
ad909e21 SRRH |
528 | tracing_off(); |
529 | return; | |
530 | } | |
531 | ||
532 | /* Note, snapshot can not be used when the tracer uses it */ | |
533 | if (tracer->use_max_tr) { | |
ca268da6 SRRH |
534 | internal_trace_puts("*** LATENCY TRACER ACTIVE ***\n"); |
535 | internal_trace_puts("*** Can not use snapshot (sorry) ***\n"); | |
ad909e21 SRRH |
536 | return; |
537 | } | |
538 | ||
539 | local_irq_save(flags); | |
540 | update_max_tr(tr, current, smp_processor_id()); | |
541 | local_irq_restore(flags); | |
542 | } | |
1b22e382 | 543 | EXPORT_SYMBOL_GPL(tracing_snapshot); |
ad909e21 SRRH |
544 | |
545 | static int resize_buffer_duplicate_size(struct trace_buffer *trace_buf, | |
546 | struct trace_buffer *size_buf, int cpu_id); | |
3209cff4 SRRH |
547 | static void set_buffer_entries(struct trace_buffer *buf, unsigned long val); |
548 | ||
549 | static int alloc_snapshot(struct trace_array *tr) | |
550 | { | |
551 | int ret; | |
552 | ||
553 | if (!tr->allocated_snapshot) { | |
554 | ||
555 | /* allocate spare buffer */ | |
556 | ret = resize_buffer_duplicate_size(&tr->max_buffer, | |
557 | &tr->trace_buffer, RING_BUFFER_ALL_CPUS); | |
558 | if (ret < 0) | |
559 | return ret; | |
560 | ||
561 | tr->allocated_snapshot = true; | |
562 | } | |
563 | ||
564 | return 0; | |
565 | } | |
566 | ||
567 | void free_snapshot(struct trace_array *tr) | |
568 | { | |
569 | /* | |
570 | * We don't free the ring buffer. instead, resize it because | |
571 | * The max_tr ring buffer has some state (e.g. ring->clock) and | |
572 | * we want preserve it. | |
573 | */ | |
574 | ring_buffer_resize(tr->max_buffer.buffer, 1, RING_BUFFER_ALL_CPUS); | |
575 | set_buffer_entries(&tr->max_buffer, 1); | |
576 | tracing_reset_online_cpus(&tr->max_buffer); | |
577 | tr->allocated_snapshot = false; | |
578 | } | |
ad909e21 SRRH |
579 | |
580 | /** | |
581 | * trace_snapshot_alloc - allocate and take a snapshot of the current buffer. | |
582 | * | |
583 | * This is similar to trace_snapshot(), but it will allocate the | |
584 | * snapshot buffer if it isn't already allocated. Use this only | |
585 | * where it is safe to sleep, as the allocation may sleep. | |
586 | * | |
587 | * This causes a swap between the snapshot buffer and the current live | |
588 | * tracing buffer. You can use this to take snapshots of the live | |
589 | * trace when some condition is triggered, but continue to trace. | |
590 | */ | |
591 | void tracing_snapshot_alloc(void) | |
592 | { | |
593 | struct trace_array *tr = &global_trace; | |
594 | int ret; | |
595 | ||
3209cff4 SRRH |
596 | ret = alloc_snapshot(tr); |
597 | if (WARN_ON(ret < 0)) | |
598 | return; | |
ad909e21 SRRH |
599 | |
600 | tracing_snapshot(); | |
601 | } | |
1b22e382 | 602 | EXPORT_SYMBOL_GPL(tracing_snapshot_alloc); |
ad909e21 SRRH |
603 | #else |
604 | void tracing_snapshot(void) | |
605 | { | |
606 | WARN_ONCE(1, "Snapshot feature not enabled, but internal snapshot used"); | |
607 | } | |
1b22e382 | 608 | EXPORT_SYMBOL_GPL(tracing_snapshot); |
ad909e21 SRRH |
609 | void tracing_snapshot_alloc(void) |
610 | { | |
611 | /* Give warning */ | |
612 | tracing_snapshot(); | |
613 | } | |
1b22e382 | 614 | EXPORT_SYMBOL_GPL(tracing_snapshot_alloc); |
ad909e21 SRRH |
615 | #endif /* CONFIG_TRACER_SNAPSHOT */ |
616 | ||
2fd821ee SRRH |
617 | void tracer_tracing_off(struct trace_array *tr) |
618 | { | |
619 | if (tr->trace_buffer.buffer) | |
620 | ring_buffer_record_off(tr->trace_buffer.buffer); | |
621 | /* | |
622 | * This flag is looked at when buffers haven't been allocated | |
623 | * yet, or by some tracers (like irqsoff), that just want to | |
624 | * know if the ring buffer has been disabled, but it can handle | |
625 | * races of where it gets disabled but we still do a record. | |
626 | * As the check is in the fast path of the tracers, it is more | |
627 | * important to be fast than accurate. | |
628 | */ | |
629 | tr->buffer_disabled = 1; | |
630 | /* Make the flag seen by readers */ | |
631 | smp_wmb(); | |
632 | } | |
633 | ||
499e5470 SR |
634 | /** |
635 | * tracing_off - turn off tracing buffers | |
636 | * | |
637 | * This function stops the tracing buffers from recording data. | |
638 | * It does not disable any overhead the tracers themselves may | |
639 | * be causing. This function simply causes all recording to | |
640 | * the ring buffers to fail. | |
641 | */ | |
642 | void tracing_off(void) | |
643 | { | |
2fd821ee | 644 | tracer_tracing_off(&global_trace); |
499e5470 SR |
645 | } |
646 | EXPORT_SYMBOL_GPL(tracing_off); | |
647 | ||
2fd821ee SRRH |
648 | /** |
649 | * tracer_tracing_is_on - show real state of ring buffer enabled | |
650 | * @tr : the trace array to know if ring buffer is enabled | |
651 | * | |
652 | * Shows real state of the ring buffer if it is enabled or not. | |
653 | */ | |
654 | int tracer_tracing_is_on(struct trace_array *tr) | |
655 | { | |
656 | if (tr->trace_buffer.buffer) | |
657 | return ring_buffer_record_is_on(tr->trace_buffer.buffer); | |
658 | return !tr->buffer_disabled; | |
659 | } | |
660 | ||
499e5470 SR |
661 | /** |
662 | * tracing_is_on - show state of ring buffers enabled | |
663 | */ | |
664 | int tracing_is_on(void) | |
665 | { | |
2fd821ee | 666 | return tracer_tracing_is_on(&global_trace); |
499e5470 SR |
667 | } |
668 | EXPORT_SYMBOL_GPL(tracing_is_on); | |
669 | ||
3928a8a2 | 670 | static int __init set_buf_size(char *str) |
bc0c38d1 | 671 | { |
3928a8a2 | 672 | unsigned long buf_size; |
c6caeeb1 | 673 | |
bc0c38d1 SR |
674 | if (!str) |
675 | return 0; | |
9d612bef | 676 | buf_size = memparse(str, &str); |
c6caeeb1 | 677 | /* nr_entries can not be zero */ |
9d612bef | 678 | if (buf_size == 0) |
c6caeeb1 | 679 | return 0; |
3928a8a2 | 680 | trace_buf_size = buf_size; |
bc0c38d1 SR |
681 | return 1; |
682 | } | |
3928a8a2 | 683 | __setup("trace_buf_size=", set_buf_size); |
bc0c38d1 | 684 | |
0e950173 TB |
685 | static int __init set_tracing_thresh(char *str) |
686 | { | |
87abb3b1 | 687 | unsigned long threshold; |
0e950173 TB |
688 | int ret; |
689 | ||
690 | if (!str) | |
691 | return 0; | |
bcd83ea6 | 692 | ret = kstrtoul(str, 0, &threshold); |
0e950173 TB |
693 | if (ret < 0) |
694 | return 0; | |
87abb3b1 | 695 | tracing_thresh = threshold * 1000; |
0e950173 TB |
696 | return 1; |
697 | } | |
698 | __setup("tracing_thresh=", set_tracing_thresh); | |
699 | ||
57f50be1 SR |
700 | unsigned long nsecs_to_usecs(unsigned long nsecs) |
701 | { | |
702 | return nsecs / 1000; | |
703 | } | |
704 | ||
4fcdae83 | 705 | /* These must match the bit postions in trace_iterator_flags */ |
bc0c38d1 SR |
706 | static const char *trace_options[] = { |
707 | "print-parent", | |
708 | "sym-offset", | |
709 | "sym-addr", | |
710 | "verbose", | |
f9896bf3 | 711 | "raw", |
5e3ca0ec | 712 | "hex", |
cb0f12aa | 713 | "bin", |
2a2cc8f7 | 714 | "block", |
86387f7e | 715 | "stacktrace", |
5e1607a0 | 716 | "trace_printk", |
b2a866f9 | 717 | "ftrace_preempt", |
9f029e83 | 718 | "branch", |
12ef7d44 | 719 | "annotate", |
02b67518 | 720 | "userstacktrace", |
b54d3de9 | 721 | "sym-userobj", |
66896a85 | 722 | "printk-msg-only", |
c4a8e8be | 723 | "context-info", |
c032ef64 | 724 | "latency-format", |
be6f164a | 725 | "sleep-time", |
a2a16d6a | 726 | "graph-time", |
e870e9a1 | 727 | "record-cmd", |
750912fa | 728 | "overwrite", |
cf30cf67 | 729 | "disable_on_free", |
77271ce4 | 730 | "irq-info", |
5224c3a3 | 731 | "markers", |
328df475 | 732 | "function-trace", |
bc0c38d1 SR |
733 | NULL |
734 | }; | |
735 | ||
5079f326 Z |
736 | static struct { |
737 | u64 (*func)(void); | |
738 | const char *name; | |
8be0709f | 739 | int in_ns; /* is this clock in nanoseconds? */ |
5079f326 | 740 | } trace_clocks[] = { |
8be0709f DS |
741 | { trace_clock_local, "local", 1 }, |
742 | { trace_clock_global, "global", 1 }, | |
743 | { trace_clock_counter, "counter", 0 }, | |
efd39f77 | 744 | { trace_clock_jiffies, "uptime", 0 }, |
76f11917 | 745 | { trace_clock, "perf", 1 }, |
8cbd9cc6 | 746 | ARCH_TRACE_CLOCKS |
5079f326 Z |
747 | }; |
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; | |
84300636 | 843 | } else if (parser->idx < parser->size - 1) { |
b63f39ea | 844 | parser->cont = true; |
845 | parser->buffer[parser->idx++] = ch; | |
84300636 SR |
846 | } else { |
847 | ret = -EINVAL; | |
848 | goto out; | |
b63f39ea | 849 | } |
850 | ||
851 | *ppos += read; | |
852 | ret = read; | |
853 | ||
854 | out: | |
855 | return ret; | |
856 | } | |
857 | ||
6c6c2796 PP |
858 | ssize_t trace_seq_to_user(struct trace_seq *s, char __user *ubuf, size_t cnt) |
859 | { | |
860 | int len; | |
861 | int ret; | |
862 | ||
2dc5d12b SR |
863 | if (!cnt) |
864 | return 0; | |
865 | ||
6c6c2796 PP |
866 | if (s->len <= s->readpos) |
867 | return -EBUSY; | |
868 | ||
869 | len = s->len - s->readpos; | |
870 | if (cnt > len) | |
871 | cnt = len; | |
872 | ret = copy_to_user(ubuf, s->buffer + s->readpos, cnt); | |
2dc5d12b | 873 | if (ret == cnt) |
6c6c2796 PP |
874 | return -EFAULT; |
875 | ||
2dc5d12b SR |
876 | cnt -= ret; |
877 | ||
e74da523 | 878 | s->readpos += cnt; |
6c6c2796 | 879 | return cnt; |
214023c3 SR |
880 | } |
881 | ||
b8b94265 | 882 | static ssize_t trace_seq_to_buffer(struct trace_seq *s, void *buf, size_t cnt) |
3c56819b EGM |
883 | { |
884 | int len; | |
3c56819b EGM |
885 | |
886 | if (s->len <= s->readpos) | |
887 | return -EBUSY; | |
888 | ||
889 | len = s->len - s->readpos; | |
890 | if (cnt > len) | |
891 | cnt = len; | |
5a26c8f0 | 892 | memcpy(buf, s->buffer + s->readpos, cnt); |
3c56819b | 893 | |
e74da523 | 894 | s->readpos += cnt; |
3c56819b EGM |
895 | return cnt; |
896 | } | |
897 | ||
5d4a9dba SR |
898 | /* |
899 | * ftrace_max_lock is used to protect the swapping of buffers | |
900 | * when taking a max snapshot. The buffers themselves are | |
901 | * protected by per_cpu spinlocks. But the action of the swap | |
902 | * needs its own lock. | |
903 | * | |
445c8951 | 904 | * This is defined as a arch_spinlock_t in order to help |
5d4a9dba SR |
905 | * with performance when lockdep debugging is enabled. |
906 | * | |
907 | * It is also used in other places outside the update_max_tr | |
908 | * so it needs to be defined outside of the | |
909 | * CONFIG_TRACER_MAX_TRACE. | |
910 | */ | |
445c8951 | 911 | static arch_spinlock_t ftrace_max_lock = |
edc35bd7 | 912 | (arch_spinlock_t)__ARCH_SPIN_LOCK_UNLOCKED; |
5d4a9dba | 913 | |
0e950173 TB |
914 | unsigned long __read_mostly tracing_thresh; |
915 | ||
5d4a9dba SR |
916 | #ifdef CONFIG_TRACER_MAX_TRACE |
917 | unsigned long __read_mostly tracing_max_latency; | |
5d4a9dba SR |
918 | |
919 | /* | |
920 | * Copy the new maximum trace into the separate maximum-trace | |
921 | * structure. (this way the maximum trace is permanently saved, | |
922 | * for later retrieval via /sys/kernel/debug/tracing/latency_trace) | |
923 | */ | |
924 | static void | |
925 | __update_max_tr(struct trace_array *tr, struct task_struct *tsk, int cpu) | |
926 | { | |
12883efb SRRH |
927 | struct trace_buffer *trace_buf = &tr->trace_buffer; |
928 | struct trace_buffer *max_buf = &tr->max_buffer; | |
929 | struct trace_array_cpu *data = per_cpu_ptr(trace_buf->data, cpu); | |
930 | struct trace_array_cpu *max_data = per_cpu_ptr(max_buf->data, cpu); | |
5d4a9dba | 931 | |
12883efb SRRH |
932 | max_buf->cpu = cpu; |
933 | max_buf->time_start = data->preempt_timestamp; | |
5d4a9dba | 934 | |
8248ac05 SR |
935 | max_data->saved_latency = tracing_max_latency; |
936 | max_data->critical_start = data->critical_start; | |
937 | max_data->critical_end = data->critical_end; | |
5d4a9dba | 938 | |
1acaa1b2 | 939 | memcpy(max_data->comm, tsk->comm, TASK_COMM_LEN); |
8248ac05 | 940 | max_data->pid = tsk->pid; |
f17a5194 SRRH |
941 | /* |
942 | * If tsk == current, then use current_uid(), as that does not use | |
943 | * RCU. The irq tracer can be called out of RCU scope. | |
944 | */ | |
945 | if (tsk == current) | |
946 | max_data->uid = current_uid(); | |
947 | else | |
948 | max_data->uid = task_uid(tsk); | |
949 | ||
8248ac05 SR |
950 | max_data->nice = tsk->static_prio - 20 - MAX_RT_PRIO; |
951 | max_data->policy = tsk->policy; | |
952 | max_data->rt_priority = tsk->rt_priority; | |
5d4a9dba SR |
953 | |
954 | /* record this tasks comm */ | |
955 | tracing_record_cmdline(tsk); | |
956 | } | |
957 | ||
4fcdae83 SR |
958 | /** |
959 | * update_max_tr - snapshot all trace buffers from global_trace to max_tr | |
960 | * @tr: tracer | |
961 | * @tsk: the task with the latency | |
962 | * @cpu: The cpu that initiated the trace. | |
963 | * | |
964 | * Flip the buffers between the @tr and the max_tr and record information | |
965 | * about which task was the cause of this latency. | |
966 | */ | |
e309b41d | 967 | void |
bc0c38d1 SR |
968 | update_max_tr(struct trace_array *tr, struct task_struct *tsk, int cpu) |
969 | { | |
2721e72d | 970 | struct ring_buffer *buf; |
bc0c38d1 | 971 | |
2b6080f2 | 972 | if (tr->stop_count) |
b8de7bd1 SR |
973 | return; |
974 | ||
4c11d7ae | 975 | WARN_ON_ONCE(!irqs_disabled()); |
34600f0e | 976 | |
45ad21ca | 977 | if (!tr->allocated_snapshot) { |
debdd57f | 978 | /* Only the nop tracer should hit this when disabling */ |
2b6080f2 | 979 | WARN_ON_ONCE(tr->current_trace != &nop_trace); |
34600f0e | 980 | return; |
debdd57f | 981 | } |
34600f0e | 982 | |
0199c4e6 | 983 | arch_spin_lock(&ftrace_max_lock); |
3928a8a2 | 984 | |
12883efb SRRH |
985 | buf = tr->trace_buffer.buffer; |
986 | tr->trace_buffer.buffer = tr->max_buffer.buffer; | |
987 | tr->max_buffer.buffer = buf; | |
3928a8a2 | 988 | |
bc0c38d1 | 989 | __update_max_tr(tr, tsk, cpu); |
0199c4e6 | 990 | arch_spin_unlock(&ftrace_max_lock); |
bc0c38d1 SR |
991 | } |
992 | ||
993 | /** | |
994 | * update_max_tr_single - only copy one trace over, and reset the rest | |
995 | * @tr - tracer | |
996 | * @tsk - task with the latency | |
997 | * @cpu - the cpu of the buffer to copy. | |
4fcdae83 SR |
998 | * |
999 | * Flip the trace of a single CPU buffer between the @tr and the max_tr. | |
bc0c38d1 | 1000 | */ |
e309b41d | 1001 | void |
bc0c38d1 SR |
1002 | update_max_tr_single(struct trace_array *tr, struct task_struct *tsk, int cpu) |
1003 | { | |
3928a8a2 | 1004 | int ret; |
bc0c38d1 | 1005 | |
2b6080f2 | 1006 | if (tr->stop_count) |
b8de7bd1 SR |
1007 | return; |
1008 | ||
4c11d7ae | 1009 | WARN_ON_ONCE(!irqs_disabled()); |
6c24499f | 1010 | if (!tr->allocated_snapshot) { |
2930e04d | 1011 | /* Only the nop tracer should hit this when disabling */ |
9e8529af | 1012 | WARN_ON_ONCE(tr->current_trace != &nop_trace); |
ef710e10 | 1013 | return; |
2930e04d | 1014 | } |
ef710e10 | 1015 | |
0199c4e6 | 1016 | arch_spin_lock(&ftrace_max_lock); |
bc0c38d1 | 1017 | |
12883efb | 1018 | ret = ring_buffer_swap_cpu(tr->max_buffer.buffer, tr->trace_buffer.buffer, cpu); |
3928a8a2 | 1019 | |
e8165dbb SR |
1020 | if (ret == -EBUSY) { |
1021 | /* | |
1022 | * We failed to swap the buffer due to a commit taking | |
1023 | * place on this CPU. We fail to record, but we reset | |
1024 | * the max trace buffer (no one writes directly to it) | |
1025 | * and flag that it failed. | |
1026 | */ | |
12883efb | 1027 | trace_array_printk_buf(tr->max_buffer.buffer, _THIS_IP_, |
e8165dbb SR |
1028 | "Failed to swap buffers due to commit in progress\n"); |
1029 | } | |
1030 | ||
e8165dbb | 1031 | WARN_ON_ONCE(ret && ret != -EAGAIN && ret != -EBUSY); |
bc0c38d1 SR |
1032 | |
1033 | __update_max_tr(tr, tsk, cpu); | |
0199c4e6 | 1034 | arch_spin_unlock(&ftrace_max_lock); |
bc0c38d1 | 1035 | } |
5d4a9dba | 1036 | #endif /* CONFIG_TRACER_MAX_TRACE */ |
bc0c38d1 | 1037 | |
561237e4 | 1038 | static int default_wait_pipe(struct trace_iterator *iter) |
0d5c6e1c | 1039 | { |
15693458 SRRH |
1040 | /* Iterators are static, they should be filled or empty */ |
1041 | if (trace_buffer_iter(iter, iter->cpu_file)) | |
561237e4 | 1042 | return 0; |
0d5c6e1c | 1043 | |
561237e4 | 1044 | return ring_buffer_wait(iter->trace_buffer->buffer, iter->cpu_file); |
0d5c6e1c SR |
1045 | } |
1046 | ||
f4e781c0 SRRH |
1047 | #ifdef CONFIG_FTRACE_STARTUP_TEST |
1048 | static int run_tracer_selftest(struct tracer *type) | |
1049 | { | |
1050 | struct trace_array *tr = &global_trace; | |
1051 | struct tracer *saved_tracer = tr->current_trace; | |
1052 | int ret; | |
0d5c6e1c | 1053 | |
f4e781c0 SRRH |
1054 | if (!type->selftest || tracing_selftest_disabled) |
1055 | return 0; | |
0d5c6e1c SR |
1056 | |
1057 | /* | |
f4e781c0 SRRH |
1058 | * Run a selftest on this tracer. |
1059 | * Here we reset the trace buffer, and set the current | |
1060 | * tracer to be this tracer. The tracer can then run some | |
1061 | * internal tracing to verify that everything is in order. | |
1062 | * If we fail, we do not register this tracer. | |
0d5c6e1c | 1063 | */ |
f4e781c0 | 1064 | tracing_reset_online_cpus(&tr->trace_buffer); |
0d5c6e1c | 1065 | |
f4e781c0 SRRH |
1066 | tr->current_trace = type; |
1067 | ||
1068 | #ifdef CONFIG_TRACER_MAX_TRACE | |
1069 | if (type->use_max_tr) { | |
1070 | /* If we expanded the buffers, make sure the max is expanded too */ | |
1071 | if (ring_buffer_expanded) | |
1072 | ring_buffer_resize(tr->max_buffer.buffer, trace_buf_size, | |
1073 | RING_BUFFER_ALL_CPUS); | |
1074 | tr->allocated_snapshot = true; | |
1075 | } | |
1076 | #endif | |
1077 | ||
1078 | /* the test is responsible for initializing and enabling */ | |
1079 | pr_info("Testing tracer %s: ", type->name); | |
1080 | ret = type->selftest(type, tr); | |
1081 | /* the test is responsible for resetting too */ | |
1082 | tr->current_trace = saved_tracer; | |
1083 | if (ret) { | |
1084 | printk(KERN_CONT "FAILED!\n"); | |
1085 | /* Add the warning after printing 'FAILED' */ | |
1086 | WARN_ON(1); | |
1087 | return -1; | |
1088 | } | |
1089 | /* Only reset on passing, to avoid touching corrupted buffers */ | |
1090 | tracing_reset_online_cpus(&tr->trace_buffer); | |
1091 | ||
1092 | #ifdef CONFIG_TRACER_MAX_TRACE | |
1093 | if (type->use_max_tr) { | |
1094 | tr->allocated_snapshot = false; | |
0d5c6e1c | 1095 | |
f4e781c0 SRRH |
1096 | /* Shrink the max buffer again */ |
1097 | if (ring_buffer_expanded) | |
1098 | ring_buffer_resize(tr->max_buffer.buffer, 1, | |
1099 | RING_BUFFER_ALL_CPUS); | |
1100 | } | |
1101 | #endif | |
1102 | ||
1103 | printk(KERN_CONT "PASSED\n"); | |
1104 | return 0; | |
1105 | } | |
1106 | #else | |
1107 | static inline int run_tracer_selftest(struct tracer *type) | |
1108 | { | |
1109 | return 0; | |
0d5c6e1c | 1110 | } |
f4e781c0 | 1111 | #endif /* CONFIG_FTRACE_STARTUP_TEST */ |
0d5c6e1c | 1112 | |
4fcdae83 SR |
1113 | /** |
1114 | * register_tracer - register a tracer with the ftrace system. | |
1115 | * @type - the plugin for the tracer | |
1116 | * | |
1117 | * Register a new plugin tracer. | |
1118 | */ | |
bc0c38d1 SR |
1119 | int register_tracer(struct tracer *type) |
1120 | { | |
1121 | struct tracer *t; | |
bc0c38d1 SR |
1122 | int ret = 0; |
1123 | ||
1124 | if (!type->name) { | |
1125 | pr_info("Tracer must have a name\n"); | |
1126 | return -1; | |
1127 | } | |
1128 | ||
24a461d5 | 1129 | if (strlen(type->name) >= MAX_TRACER_SIZE) { |
ee6c2c1b LZ |
1130 | pr_info("Tracer has a name longer than %d\n", MAX_TRACER_SIZE); |
1131 | return -1; | |
1132 | } | |
1133 | ||
bc0c38d1 | 1134 | mutex_lock(&trace_types_lock); |
86fa2f60 | 1135 | |
8e1b82e0 FW |
1136 | tracing_selftest_running = true; |
1137 | ||
bc0c38d1 SR |
1138 | for (t = trace_types; t; t = t->next) { |
1139 | if (strcmp(type->name, t->name) == 0) { | |
1140 | /* already found */ | |
ee6c2c1b | 1141 | pr_info("Tracer %s already registered\n", |
bc0c38d1 SR |
1142 | type->name); |
1143 | ret = -1; | |
1144 | goto out; | |
1145 | } | |
1146 | } | |
1147 | ||
adf9f195 FW |
1148 | if (!type->set_flag) |
1149 | type->set_flag = &dummy_set_flag; | |
1150 | if (!type->flags) | |
1151 | type->flags = &dummy_tracer_flags; | |
1152 | else | |
1153 | if (!type->flags->opts) | |
1154 | type->flags->opts = dummy_tracer_opt; | |
6eaaa5d5 FW |
1155 | if (!type->wait_pipe) |
1156 | type->wait_pipe = default_wait_pipe; | |
1157 | ||
f4e781c0 SRRH |
1158 | ret = run_tracer_selftest(type); |
1159 | if (ret < 0) | |
1160 | goto out; | |
60a11774 | 1161 | |
bc0c38d1 SR |
1162 | type->next = trace_types; |
1163 | trace_types = type; | |
60a11774 | 1164 | |
bc0c38d1 | 1165 | out: |
8e1b82e0 | 1166 | tracing_selftest_running = false; |
bc0c38d1 SR |
1167 | mutex_unlock(&trace_types_lock); |
1168 | ||
dac74940 SR |
1169 | if (ret || !default_bootup_tracer) |
1170 | goto out_unlock; | |
1171 | ||
ee6c2c1b | 1172 | if (strncmp(default_bootup_tracer, type->name, MAX_TRACER_SIZE)) |
dac74940 SR |
1173 | goto out_unlock; |
1174 | ||
1175 | printk(KERN_INFO "Starting tracer '%s'\n", type->name); | |
1176 | /* Do we want this tracer to start on bootup? */ | |
1177 | tracing_set_tracer(type->name); | |
1178 | default_bootup_tracer = NULL; | |
1179 | /* disable other selftests, since this will break it. */ | |
55034cd6 | 1180 | tracing_selftest_disabled = true; |
b2821ae6 | 1181 | #ifdef CONFIG_FTRACE_STARTUP_TEST |
dac74940 SR |
1182 | printk(KERN_INFO "Disabling FTRACE selftests due to running tracer '%s'\n", |
1183 | type->name); | |
b2821ae6 | 1184 | #endif |
b2821ae6 | 1185 | |
dac74940 | 1186 | out_unlock: |
bc0c38d1 SR |
1187 | return ret; |
1188 | } | |
1189 | ||
12883efb | 1190 | void tracing_reset(struct trace_buffer *buf, int cpu) |
f633903a | 1191 | { |
12883efb | 1192 | struct ring_buffer *buffer = buf->buffer; |
f633903a | 1193 | |
a5416411 HT |
1194 | if (!buffer) |
1195 | return; | |
1196 | ||
f633903a SR |
1197 | ring_buffer_record_disable(buffer); |
1198 | ||
1199 | /* Make sure all commits have finished */ | |
1200 | synchronize_sched(); | |
68179686 | 1201 | ring_buffer_reset_cpu(buffer, cpu); |
f633903a SR |
1202 | |
1203 | ring_buffer_record_enable(buffer); | |
1204 | } | |
1205 | ||
12883efb | 1206 | void tracing_reset_online_cpus(struct trace_buffer *buf) |
213cc060 | 1207 | { |
12883efb | 1208 | struct ring_buffer *buffer = buf->buffer; |
213cc060 PE |
1209 | int cpu; |
1210 | ||
a5416411 HT |
1211 | if (!buffer) |
1212 | return; | |
1213 | ||
621968cd SR |
1214 | ring_buffer_record_disable(buffer); |
1215 | ||
1216 | /* Make sure all commits have finished */ | |
1217 | synchronize_sched(); | |
1218 | ||
e88512e7 | 1219 | buf->time_start = buffer_ftrace_now(buf, buf->cpu); |
213cc060 PE |
1220 | |
1221 | for_each_online_cpu(cpu) | |
68179686 | 1222 | ring_buffer_reset_cpu(buffer, cpu); |
621968cd SR |
1223 | |
1224 | ring_buffer_record_enable(buffer); | |
213cc060 PE |
1225 | } |
1226 | ||
c62771c8 | 1227 | /* Must have trace_types_lock held */ |
873c642f | 1228 | void tracing_reset_all_online_cpus(void) |
9456f0fa | 1229 | { |
873c642f SRRH |
1230 | struct trace_array *tr; |
1231 | ||
873c642f | 1232 | list_for_each_entry(tr, &ftrace_trace_arrays, list) { |
12883efb SRRH |
1233 | tracing_reset_online_cpus(&tr->trace_buffer); |
1234 | #ifdef CONFIG_TRACER_MAX_TRACE | |
1235 | tracing_reset_online_cpus(&tr->max_buffer); | |
1236 | #endif | |
873c642f | 1237 | } |
9456f0fa SR |
1238 | } |
1239 | ||
bc0c38d1 | 1240 | #define SAVED_CMDLINES 128 |
2c7eea4c | 1241 | #define NO_CMDLINE_MAP UINT_MAX |
bc0c38d1 SR |
1242 | static unsigned map_pid_to_cmdline[PID_MAX_DEFAULT+1]; |
1243 | static unsigned map_cmdline_to_pid[SAVED_CMDLINES]; | |
1244 | static char saved_cmdlines[SAVED_CMDLINES][TASK_COMM_LEN]; | |
1245 | static int cmdline_idx; | |
edc35bd7 | 1246 | static arch_spinlock_t trace_cmdline_lock = __ARCH_SPIN_LOCK_UNLOCKED; |
25b0b44a | 1247 | |
25b0b44a | 1248 | /* temporary disable recording */ |
4fd27358 | 1249 | static atomic_t trace_record_cmdline_disabled __read_mostly; |
bc0c38d1 SR |
1250 | |
1251 | static void trace_init_cmdlines(void) | |
1252 | { | |
2c7eea4c TG |
1253 | memset(&map_pid_to_cmdline, NO_CMDLINE_MAP, sizeof(map_pid_to_cmdline)); |
1254 | memset(&map_cmdline_to_pid, NO_CMDLINE_MAP, sizeof(map_cmdline_to_pid)); | |
bc0c38d1 SR |
1255 | cmdline_idx = 0; |
1256 | } | |
1257 | ||
b5130b1e CE |
1258 | int is_tracing_stopped(void) |
1259 | { | |
2b6080f2 | 1260 | return global_trace.stop_count; |
b5130b1e CE |
1261 | } |
1262 | ||
69bb54ec SR |
1263 | /** |
1264 | * ftrace_off_permanent - disable all ftrace code permanently | |
1265 | * | |
1266 | * This should only be called when a serious anomally has | |
1267 | * been detected. This will turn off the function tracing, | |
1268 | * ring buffers, and other tracing utilites. It takes no | |
1269 | * locks and can be called from any context. | |
1270 | */ | |
1271 | void ftrace_off_permanent(void) | |
1272 | { | |
1273 | tracing_disabled = 1; | |
1274 | ftrace_stop(); | |
1275 | tracing_off_permanent(); | |
1276 | } | |
1277 | ||
0f048701 SR |
1278 | /** |
1279 | * tracing_start - quick start of the tracer | |
1280 | * | |
1281 | * If tracing is enabled but was stopped by tracing_stop, | |
1282 | * this will start the tracer back up. | |
1283 | */ | |
1284 | void tracing_start(void) | |
1285 | { | |
1286 | struct ring_buffer *buffer; | |
1287 | unsigned long flags; | |
1288 | ||
1289 | if (tracing_disabled) | |
1290 | return; | |
1291 | ||
2b6080f2 SR |
1292 | raw_spin_lock_irqsave(&global_trace.start_lock, flags); |
1293 | if (--global_trace.stop_count) { | |
1294 | if (global_trace.stop_count < 0) { | |
b06a8301 SR |
1295 | /* Someone screwed up their debugging */ |
1296 | WARN_ON_ONCE(1); | |
2b6080f2 | 1297 | global_trace.stop_count = 0; |
b06a8301 | 1298 | } |
0f048701 SR |
1299 | goto out; |
1300 | } | |
1301 | ||
a2f80714 SR |
1302 | /* Prevent the buffers from switching */ |
1303 | arch_spin_lock(&ftrace_max_lock); | |
0f048701 | 1304 | |
12883efb | 1305 | buffer = global_trace.trace_buffer.buffer; |
0f048701 SR |
1306 | if (buffer) |
1307 | ring_buffer_record_enable(buffer); | |
1308 | ||
12883efb SRRH |
1309 | #ifdef CONFIG_TRACER_MAX_TRACE |
1310 | buffer = global_trace.max_buffer.buffer; | |
0f048701 SR |
1311 | if (buffer) |
1312 | ring_buffer_record_enable(buffer); | |
12883efb | 1313 | #endif |
0f048701 | 1314 | |
a2f80714 SR |
1315 | arch_spin_unlock(&ftrace_max_lock); |
1316 | ||
0f048701 | 1317 | out: |
2b6080f2 SR |
1318 | raw_spin_unlock_irqrestore(&global_trace.start_lock, flags); |
1319 | } | |
1320 | ||
1321 | static void tracing_start_tr(struct trace_array *tr) | |
1322 | { | |
1323 | struct ring_buffer *buffer; | |
1324 | unsigned long flags; | |
1325 | ||
1326 | if (tracing_disabled) | |
1327 | return; | |
1328 | ||
1329 | /* If global, we need to also start the max tracer */ | |
1330 | if (tr->flags & TRACE_ARRAY_FL_GLOBAL) | |
1331 | return tracing_start(); | |
1332 | ||
1333 | raw_spin_lock_irqsave(&tr->start_lock, flags); | |
1334 | ||
1335 | if (--tr->stop_count) { | |
1336 | if (tr->stop_count < 0) { | |
1337 | /* Someone screwed up their debugging */ | |
1338 | WARN_ON_ONCE(1); | |
1339 | tr->stop_count = 0; | |
1340 | } | |
1341 | goto out; | |
1342 | } | |
1343 | ||
12883efb | 1344 | buffer = tr->trace_buffer.buffer; |
2b6080f2 SR |
1345 | if (buffer) |
1346 | ring_buffer_record_enable(buffer); | |
1347 | ||
1348 | out: | |
1349 | raw_spin_unlock_irqrestore(&tr->start_lock, flags); | |
0f048701 SR |
1350 | } |
1351 | ||
1352 | /** | |
1353 | * tracing_stop - quick stop of the tracer | |
1354 | * | |
1355 | * Light weight way to stop tracing. Use in conjunction with | |
1356 | * tracing_start. | |
1357 | */ | |
1358 | void tracing_stop(void) | |
1359 | { | |
1360 | struct ring_buffer *buffer; | |
1361 | unsigned long flags; | |
1362 | ||
2b6080f2 SR |
1363 | raw_spin_lock_irqsave(&global_trace.start_lock, flags); |
1364 | if (global_trace.stop_count++) | |
0f048701 SR |
1365 | goto out; |
1366 | ||
a2f80714 SR |
1367 | /* Prevent the buffers from switching */ |
1368 | arch_spin_lock(&ftrace_max_lock); | |
1369 | ||
12883efb | 1370 | buffer = global_trace.trace_buffer.buffer; |
0f048701 SR |
1371 | if (buffer) |
1372 | ring_buffer_record_disable(buffer); | |
1373 | ||
12883efb SRRH |
1374 | #ifdef CONFIG_TRACER_MAX_TRACE |
1375 | buffer = global_trace.max_buffer.buffer; | |
0f048701 SR |
1376 | if (buffer) |
1377 | ring_buffer_record_disable(buffer); | |
12883efb | 1378 | #endif |
0f048701 | 1379 | |
a2f80714 SR |
1380 | arch_spin_unlock(&ftrace_max_lock); |
1381 | ||
0f048701 | 1382 | out: |
2b6080f2 SR |
1383 | raw_spin_unlock_irqrestore(&global_trace.start_lock, flags); |
1384 | } | |
1385 | ||
1386 | static void tracing_stop_tr(struct trace_array *tr) | |
1387 | { | |
1388 | struct ring_buffer *buffer; | |
1389 | unsigned long flags; | |
1390 | ||
1391 | /* If global, we need to also stop the max tracer */ | |
1392 | if (tr->flags & TRACE_ARRAY_FL_GLOBAL) | |
1393 | return tracing_stop(); | |
1394 | ||
1395 | raw_spin_lock_irqsave(&tr->start_lock, flags); | |
1396 | if (tr->stop_count++) | |
1397 | goto out; | |
1398 | ||
12883efb | 1399 | buffer = tr->trace_buffer.buffer; |
2b6080f2 SR |
1400 | if (buffer) |
1401 | ring_buffer_record_disable(buffer); | |
1402 | ||
1403 | out: | |
1404 | raw_spin_unlock_irqrestore(&tr->start_lock, flags); | |
0f048701 SR |
1405 | } |
1406 | ||
e309b41d | 1407 | void trace_stop_cmdline_recording(void); |
bc0c38d1 | 1408 | |
c5bce736 | 1409 | static int trace_save_cmdline(struct task_struct *tsk) |
bc0c38d1 | 1410 | { |
a635cf04 | 1411 | unsigned pid, idx; |
bc0c38d1 SR |
1412 | |
1413 | if (!tsk->pid || unlikely(tsk->pid > PID_MAX_DEFAULT)) | |
c5bce736 | 1414 | return 0; |
bc0c38d1 SR |
1415 | |
1416 | /* | |
1417 | * It's not the end of the world if we don't get | |
1418 | * the lock, but we also don't want to spin | |
1419 | * nor do we want to disable interrupts, | |
1420 | * so if we miss here, then better luck next time. | |
1421 | */ | |
0199c4e6 | 1422 | if (!arch_spin_trylock(&trace_cmdline_lock)) |
c5bce736 | 1423 | return 0; |
bc0c38d1 SR |
1424 | |
1425 | idx = map_pid_to_cmdline[tsk->pid]; | |
2c7eea4c | 1426 | if (idx == NO_CMDLINE_MAP) { |
bc0c38d1 SR |
1427 | idx = (cmdline_idx + 1) % SAVED_CMDLINES; |
1428 | ||
a635cf04 CE |
1429 | /* |
1430 | * Check whether the cmdline buffer at idx has a pid | |
1431 | * mapped. We are going to overwrite that entry so we | |
1432 | * need to clear the map_pid_to_cmdline. Otherwise we | |
1433 | * would read the new comm for the old pid. | |
1434 | */ | |
1435 | pid = map_cmdline_to_pid[idx]; | |
1436 | if (pid != NO_CMDLINE_MAP) | |
1437 | map_pid_to_cmdline[pid] = NO_CMDLINE_MAP; | |
bc0c38d1 | 1438 | |
a635cf04 | 1439 | map_cmdline_to_pid[idx] = tsk->pid; |
bc0c38d1 SR |
1440 | map_pid_to_cmdline[tsk->pid] = idx; |
1441 | ||
1442 | cmdline_idx = idx; | |
1443 | } | |
1444 | ||
1445 | memcpy(&saved_cmdlines[idx], tsk->comm, TASK_COMM_LEN); | |
1446 | ||
0199c4e6 | 1447 | arch_spin_unlock(&trace_cmdline_lock); |
c5bce736 SRRH |
1448 | |
1449 | return 1; | |
bc0c38d1 SR |
1450 | } |
1451 | ||
4ca53085 | 1452 | void trace_find_cmdline(int pid, char comm[]) |
bc0c38d1 | 1453 | { |
bc0c38d1 SR |
1454 | unsigned map; |
1455 | ||
4ca53085 SR |
1456 | if (!pid) { |
1457 | strcpy(comm, "<idle>"); | |
1458 | return; | |
1459 | } | |
bc0c38d1 | 1460 | |
74bf4076 SR |
1461 | if (WARN_ON_ONCE(pid < 0)) { |
1462 | strcpy(comm, "<XXX>"); | |
1463 | return; | |
1464 | } | |
1465 | ||
4ca53085 SR |
1466 | if (pid > PID_MAX_DEFAULT) { |
1467 | strcpy(comm, "<...>"); | |
1468 | return; | |
1469 | } | |
bc0c38d1 | 1470 | |
5b6045a9 | 1471 | preempt_disable(); |
0199c4e6 | 1472 | arch_spin_lock(&trace_cmdline_lock); |
bc0c38d1 | 1473 | map = map_pid_to_cmdline[pid]; |
50d88758 TG |
1474 | if (map != NO_CMDLINE_MAP) |
1475 | strcpy(comm, saved_cmdlines[map]); | |
1476 | else | |
1477 | strcpy(comm, "<...>"); | |
bc0c38d1 | 1478 | |
0199c4e6 | 1479 | arch_spin_unlock(&trace_cmdline_lock); |
5b6045a9 | 1480 | preempt_enable(); |
bc0c38d1 SR |
1481 | } |
1482 | ||
e309b41d | 1483 | void tracing_record_cmdline(struct task_struct *tsk) |
bc0c38d1 | 1484 | { |
0fb9656d | 1485 | if (atomic_read(&trace_record_cmdline_disabled) || !tracing_is_on()) |
bc0c38d1 SR |
1486 | return; |
1487 | ||
7ffbd48d SR |
1488 | if (!__this_cpu_read(trace_cmdline_save)) |
1489 | return; | |
1490 | ||
c5bce736 SRRH |
1491 | if (trace_save_cmdline(tsk)) |
1492 | __this_cpu_write(trace_cmdline_save, false); | |
bc0c38d1 SR |
1493 | } |
1494 | ||
45dcd8b8 | 1495 | void |
38697053 SR |
1496 | tracing_generic_entry_update(struct trace_entry *entry, unsigned long flags, |
1497 | int pc) | |
bc0c38d1 SR |
1498 | { |
1499 | struct task_struct *tsk = current; | |
bc0c38d1 | 1500 | |
777e208d SR |
1501 | entry->preempt_count = pc & 0xff; |
1502 | entry->pid = (tsk) ? tsk->pid : 0; | |
1503 | entry->flags = | |
9244489a | 1504 | #ifdef CONFIG_TRACE_IRQFLAGS_SUPPORT |
2e2ca155 | 1505 | (irqs_disabled_flags(flags) ? TRACE_FLAG_IRQS_OFF : 0) | |
9244489a SR |
1506 | #else |
1507 | TRACE_FLAG_IRQS_NOSUPPORT | | |
1508 | #endif | |
bc0c38d1 SR |
1509 | ((pc & HARDIRQ_MASK) ? TRACE_FLAG_HARDIRQ : 0) | |
1510 | ((pc & SOFTIRQ_MASK) ? TRACE_FLAG_SOFTIRQ : 0) | | |
1511 | (need_resched() ? TRACE_FLAG_NEED_RESCHED : 0); | |
1512 | } | |
f413cdb8 | 1513 | EXPORT_SYMBOL_GPL(tracing_generic_entry_update); |
bc0c38d1 | 1514 | |
e77405ad SR |
1515 | struct ring_buffer_event * |
1516 | trace_buffer_lock_reserve(struct ring_buffer *buffer, | |
1517 | int type, | |
1518 | unsigned long len, | |
1519 | unsigned long flags, int pc) | |
51a763dd ACM |
1520 | { |
1521 | struct ring_buffer_event *event; | |
1522 | ||
e77405ad | 1523 | event = ring_buffer_lock_reserve(buffer, len); |
51a763dd ACM |
1524 | if (event != NULL) { |
1525 | struct trace_entry *ent = ring_buffer_event_data(event); | |
1526 | ||
1527 | tracing_generic_entry_update(ent, flags, pc); | |
1528 | ent->type = type; | |
1529 | } | |
1530 | ||
1531 | return event; | |
1532 | } | |
51a763dd | 1533 | |
7ffbd48d SR |
1534 | void |
1535 | __buffer_unlock_commit(struct ring_buffer *buffer, struct ring_buffer_event *event) | |
1536 | { | |
1537 | __this_cpu_write(trace_cmdline_save, true); | |
1538 | ring_buffer_unlock_commit(buffer, event); | |
1539 | } | |
1540 | ||
e77405ad SR |
1541 | static inline void |
1542 | __trace_buffer_unlock_commit(struct ring_buffer *buffer, | |
1543 | struct ring_buffer_event *event, | |
0d5c6e1c | 1544 | unsigned long flags, int pc) |
51a763dd | 1545 | { |
7ffbd48d | 1546 | __buffer_unlock_commit(buffer, event); |
51a763dd | 1547 | |
e77405ad SR |
1548 | ftrace_trace_stack(buffer, flags, 6, pc); |
1549 | ftrace_trace_userstack(buffer, flags, pc); | |
07edf712 FW |
1550 | } |
1551 | ||
e77405ad SR |
1552 | void trace_buffer_unlock_commit(struct ring_buffer *buffer, |
1553 | struct ring_buffer_event *event, | |
1554 | unsigned long flags, int pc) | |
07edf712 | 1555 | { |
0d5c6e1c | 1556 | __trace_buffer_unlock_commit(buffer, event, flags, pc); |
51a763dd | 1557 | } |
0d5c6e1c | 1558 | EXPORT_SYMBOL_GPL(trace_buffer_unlock_commit); |
51a763dd | 1559 | |
ccb469a1 SR |
1560 | struct ring_buffer_event * |
1561 | trace_event_buffer_lock_reserve(struct ring_buffer **current_rb, | |
1562 | struct ftrace_event_file *ftrace_file, | |
1563 | int type, unsigned long len, | |
1564 | unsigned long flags, int pc) | |
1565 | { | |
12883efb | 1566 | *current_rb = ftrace_file->tr->trace_buffer.buffer; |
ccb469a1 SR |
1567 | return trace_buffer_lock_reserve(*current_rb, |
1568 | type, len, flags, pc); | |
1569 | } | |
1570 | EXPORT_SYMBOL_GPL(trace_event_buffer_lock_reserve); | |
1571 | ||
ef5580d0 | 1572 | struct ring_buffer_event * |
e77405ad SR |
1573 | trace_current_buffer_lock_reserve(struct ring_buffer **current_rb, |
1574 | int type, unsigned long len, | |
ef5580d0 SR |
1575 | unsigned long flags, int pc) |
1576 | { | |
12883efb | 1577 | *current_rb = global_trace.trace_buffer.buffer; |
e77405ad | 1578 | return trace_buffer_lock_reserve(*current_rb, |
ef5580d0 SR |
1579 | type, len, flags, pc); |
1580 | } | |
94487d6d | 1581 | EXPORT_SYMBOL_GPL(trace_current_buffer_lock_reserve); |
ef5580d0 | 1582 | |
e77405ad SR |
1583 | void trace_current_buffer_unlock_commit(struct ring_buffer *buffer, |
1584 | struct ring_buffer_event *event, | |
ef5580d0 SR |
1585 | unsigned long flags, int pc) |
1586 | { | |
0d5c6e1c | 1587 | __trace_buffer_unlock_commit(buffer, event, flags, pc); |
07edf712 | 1588 | } |
94487d6d | 1589 | EXPORT_SYMBOL_GPL(trace_current_buffer_unlock_commit); |
07edf712 | 1590 | |
0d5c6e1c SR |
1591 | void trace_buffer_unlock_commit_regs(struct ring_buffer *buffer, |
1592 | struct ring_buffer_event *event, | |
1593 | unsigned long flags, int pc, | |
1594 | struct pt_regs *regs) | |
1fd8df2c | 1595 | { |
7ffbd48d | 1596 | __buffer_unlock_commit(buffer, event); |
1fd8df2c MH |
1597 | |
1598 | ftrace_trace_stack_regs(buffer, flags, 0, pc, regs); | |
1599 | ftrace_trace_userstack(buffer, flags, pc); | |
1600 | } | |
0d5c6e1c | 1601 | EXPORT_SYMBOL_GPL(trace_buffer_unlock_commit_regs); |
1fd8df2c | 1602 | |
e77405ad SR |
1603 | void trace_current_buffer_discard_commit(struct ring_buffer *buffer, |
1604 | struct ring_buffer_event *event) | |
77d9f465 | 1605 | { |
e77405ad | 1606 | ring_buffer_discard_commit(buffer, event); |
ef5580d0 | 1607 | } |
12acd473 | 1608 | EXPORT_SYMBOL_GPL(trace_current_buffer_discard_commit); |
ef5580d0 | 1609 | |
e309b41d | 1610 | void |
7be42151 | 1611 | trace_function(struct trace_array *tr, |
38697053 SR |
1612 | unsigned long ip, unsigned long parent_ip, unsigned long flags, |
1613 | int pc) | |
bc0c38d1 | 1614 | { |
e1112b4d | 1615 | struct ftrace_event_call *call = &event_function; |
12883efb | 1616 | struct ring_buffer *buffer = tr->trace_buffer.buffer; |
3928a8a2 | 1617 | struct ring_buffer_event *event; |
777e208d | 1618 | struct ftrace_entry *entry; |
bc0c38d1 | 1619 | |
d769041f | 1620 | /* If we are reading the ring buffer, don't trace */ |
dd17c8f7 | 1621 | if (unlikely(__this_cpu_read(ftrace_cpu_disabled))) |
d769041f SR |
1622 | return; |
1623 | ||
e77405ad | 1624 | event = trace_buffer_lock_reserve(buffer, TRACE_FN, sizeof(*entry), |
51a763dd | 1625 | flags, pc); |
3928a8a2 SR |
1626 | if (!event) |
1627 | return; | |
1628 | entry = ring_buffer_event_data(event); | |
777e208d SR |
1629 | entry->ip = ip; |
1630 | entry->parent_ip = parent_ip; | |
e1112b4d | 1631 | |
e77405ad | 1632 | if (!filter_check_discard(call, entry, buffer, event)) |
7ffbd48d | 1633 | __buffer_unlock_commit(buffer, event); |
bc0c38d1 SR |
1634 | } |
1635 | ||
e309b41d | 1636 | void |
2e0f5761 | 1637 | ftrace(struct trace_array *tr, struct trace_array_cpu *data, |
38697053 SR |
1638 | unsigned long ip, unsigned long parent_ip, unsigned long flags, |
1639 | int pc) | |
2e0f5761 IM |
1640 | { |
1641 | if (likely(!atomic_read(&data->disabled))) | |
7be42151 | 1642 | trace_function(tr, ip, parent_ip, flags, pc); |
2e0f5761 IM |
1643 | } |
1644 | ||
c0a0d0d3 | 1645 | #ifdef CONFIG_STACKTRACE |
4a9bd3f1 SR |
1646 | |
1647 | #define FTRACE_STACK_MAX_ENTRIES (PAGE_SIZE / sizeof(unsigned long)) | |
1648 | struct ftrace_stack { | |
1649 | unsigned long calls[FTRACE_STACK_MAX_ENTRIES]; | |
1650 | }; | |
1651 | ||
1652 | static DEFINE_PER_CPU(struct ftrace_stack, ftrace_stack); | |
1653 | static DEFINE_PER_CPU(int, ftrace_stack_reserve); | |
1654 | ||
e77405ad | 1655 | static void __ftrace_trace_stack(struct ring_buffer *buffer, |
53614991 | 1656 | unsigned long flags, |
1fd8df2c | 1657 | int skip, int pc, struct pt_regs *regs) |
86387f7e | 1658 | { |
e1112b4d | 1659 | struct ftrace_event_call *call = &event_kernel_stack; |
3928a8a2 | 1660 | struct ring_buffer_event *event; |
777e208d | 1661 | struct stack_entry *entry; |
86387f7e | 1662 | struct stack_trace trace; |
4a9bd3f1 SR |
1663 | int use_stack; |
1664 | int size = FTRACE_STACK_ENTRIES; | |
1665 | ||
1666 | trace.nr_entries = 0; | |
1667 | trace.skip = skip; | |
1668 | ||
1669 | /* | |
1670 | * Since events can happen in NMIs there's no safe way to | |
1671 | * use the per cpu ftrace_stacks. We reserve it and if an interrupt | |
1672 | * or NMI comes in, it will just have to use the default | |
1673 | * FTRACE_STACK_SIZE. | |
1674 | */ | |
1675 | preempt_disable_notrace(); | |
1676 | ||
82146529 | 1677 | use_stack = __this_cpu_inc_return(ftrace_stack_reserve); |
4a9bd3f1 SR |
1678 | /* |
1679 | * We don't need any atomic variables, just a barrier. | |
1680 | * If an interrupt comes in, we don't care, because it would | |
1681 | * have exited and put the counter back to what we want. | |
1682 | * We just need a barrier to keep gcc from moving things | |
1683 | * around. | |
1684 | */ | |
1685 | barrier(); | |
1686 | if (use_stack == 1) { | |
1687 | trace.entries = &__get_cpu_var(ftrace_stack).calls[0]; | |
1688 | trace.max_entries = FTRACE_STACK_MAX_ENTRIES; | |
1689 | ||
1690 | if (regs) | |
1691 | save_stack_trace_regs(regs, &trace); | |
1692 | else | |
1693 | save_stack_trace(&trace); | |
1694 | ||
1695 | if (trace.nr_entries > size) | |
1696 | size = trace.nr_entries; | |
1697 | } else | |
1698 | /* From now on, use_stack is a boolean */ | |
1699 | use_stack = 0; | |
1700 | ||
1701 | size *= sizeof(unsigned long); | |
86387f7e | 1702 | |
e77405ad | 1703 | event = trace_buffer_lock_reserve(buffer, TRACE_STACK, |
4a9bd3f1 | 1704 | sizeof(*entry) + size, flags, pc); |
3928a8a2 | 1705 | if (!event) |
4a9bd3f1 SR |
1706 | goto out; |
1707 | entry = ring_buffer_event_data(event); | |
86387f7e | 1708 | |
4a9bd3f1 SR |
1709 | memset(&entry->caller, 0, size); |
1710 | ||
1711 | if (use_stack) | |
1712 | memcpy(&entry->caller, trace.entries, | |
1713 | trace.nr_entries * sizeof(unsigned long)); | |
1714 | else { | |
1715 | trace.max_entries = FTRACE_STACK_ENTRIES; | |
1716 | trace.entries = entry->caller; | |
1717 | if (regs) | |
1718 | save_stack_trace_regs(regs, &trace); | |
1719 | else | |
1720 | save_stack_trace(&trace); | |
1721 | } | |
1722 | ||
1723 | entry->size = trace.nr_entries; | |
86387f7e | 1724 | |
e77405ad | 1725 | if (!filter_check_discard(call, entry, buffer, event)) |
7ffbd48d | 1726 | __buffer_unlock_commit(buffer, event); |
4a9bd3f1 SR |
1727 | |
1728 | out: | |
1729 | /* Again, don't let gcc optimize things here */ | |
1730 | barrier(); | |
82146529 | 1731 | __this_cpu_dec(ftrace_stack_reserve); |
4a9bd3f1 SR |
1732 | preempt_enable_notrace(); |
1733 | ||
f0a920d5 IM |
1734 | } |
1735 | ||
1fd8df2c MH |
1736 | void ftrace_trace_stack_regs(struct ring_buffer *buffer, unsigned long flags, |
1737 | int skip, int pc, struct pt_regs *regs) | |
1738 | { | |
1739 | if (!(trace_flags & TRACE_ITER_STACKTRACE)) | |
1740 | return; | |
1741 | ||
1742 | __ftrace_trace_stack(buffer, flags, skip, pc, regs); | |
1743 | } | |
1744 | ||
e77405ad SR |
1745 | void ftrace_trace_stack(struct ring_buffer *buffer, unsigned long flags, |
1746 | int skip, int pc) | |
53614991 SR |
1747 | { |
1748 | if (!(trace_flags & TRACE_ITER_STACKTRACE)) | |
1749 | return; | |
1750 | ||
1fd8df2c | 1751 | __ftrace_trace_stack(buffer, flags, skip, pc, NULL); |
53614991 SR |
1752 | } |
1753 | ||
c0a0d0d3 FW |
1754 | void __trace_stack(struct trace_array *tr, unsigned long flags, int skip, |
1755 | int pc) | |
38697053 | 1756 | { |
12883efb | 1757 | __ftrace_trace_stack(tr->trace_buffer.buffer, flags, skip, pc, NULL); |
38697053 SR |
1758 | } |
1759 | ||
03889384 SR |
1760 | /** |
1761 | * trace_dump_stack - record a stack back trace in the trace buffer | |
c142be8e | 1762 | * @skip: Number of functions to skip (helper handlers) |
03889384 | 1763 | */ |
c142be8e | 1764 | void trace_dump_stack(int skip) |
03889384 SR |
1765 | { |
1766 | unsigned long flags; | |
1767 | ||
1768 | if (tracing_disabled || tracing_selftest_running) | |
e36c5458 | 1769 | return; |
03889384 SR |
1770 | |
1771 | local_save_flags(flags); | |
1772 | ||
c142be8e SRRH |
1773 | /* |
1774 | * Skip 3 more, seems to get us at the caller of | |
1775 | * this function. | |
1776 | */ | |
1777 | skip += 3; | |
1778 | __ftrace_trace_stack(global_trace.trace_buffer.buffer, | |
1779 | flags, skip, preempt_count(), NULL); | |
03889384 SR |
1780 | } |
1781 | ||
91e86e56 SR |
1782 | static DEFINE_PER_CPU(int, user_stack_count); |
1783 | ||
e77405ad SR |
1784 | void |
1785 | ftrace_trace_userstack(struct ring_buffer *buffer, unsigned long flags, int pc) | |
02b67518 | 1786 | { |
e1112b4d | 1787 | struct ftrace_event_call *call = &event_user_stack; |
8d7c6a96 | 1788 | struct ring_buffer_event *event; |
02b67518 TE |
1789 | struct userstack_entry *entry; |
1790 | struct stack_trace trace; | |
02b67518 TE |
1791 | |
1792 | if (!(trace_flags & TRACE_ITER_USERSTACKTRACE)) | |
1793 | return; | |
1794 | ||
b6345879 SR |
1795 | /* |
1796 | * NMIs can not handle page faults, even with fix ups. | |
1797 | * The save user stack can (and often does) fault. | |
1798 | */ | |
1799 | if (unlikely(in_nmi())) | |
1800 | return; | |
02b67518 | 1801 | |
91e86e56 SR |
1802 | /* |
1803 | * prevent recursion, since the user stack tracing may | |
1804 | * trigger other kernel events. | |
1805 | */ | |
1806 | preempt_disable(); | |
1807 | if (__this_cpu_read(user_stack_count)) | |
1808 | goto out; | |
1809 | ||
1810 | __this_cpu_inc(user_stack_count); | |
1811 | ||
e77405ad | 1812 | event = trace_buffer_lock_reserve(buffer, TRACE_USER_STACK, |
51a763dd | 1813 | sizeof(*entry), flags, pc); |
02b67518 | 1814 | if (!event) |
1dbd1951 | 1815 | goto out_drop_count; |
02b67518 | 1816 | entry = ring_buffer_event_data(event); |
02b67518 | 1817 | |
48659d31 | 1818 | entry->tgid = current->tgid; |
02b67518 TE |
1819 | memset(&entry->caller, 0, sizeof(entry->caller)); |
1820 | ||
1821 | trace.nr_entries = 0; | |
1822 | trace.max_entries = FTRACE_STACK_ENTRIES; | |
1823 | trace.skip = 0; | |
1824 | trace.entries = entry->caller; | |
1825 | ||
1826 | save_stack_trace_user(&trace); | |
e77405ad | 1827 | if (!filter_check_discard(call, entry, buffer, event)) |
7ffbd48d | 1828 | __buffer_unlock_commit(buffer, event); |
91e86e56 | 1829 | |
1dbd1951 | 1830 | out_drop_count: |
91e86e56 | 1831 | __this_cpu_dec(user_stack_count); |
91e86e56 SR |
1832 | out: |
1833 | preempt_enable(); | |
02b67518 TE |
1834 | } |
1835 | ||
4fd27358 HE |
1836 | #ifdef UNUSED |
1837 | static void __trace_userstack(struct trace_array *tr, unsigned long flags) | |
02b67518 | 1838 | { |
7be42151 | 1839 | ftrace_trace_userstack(tr, flags, preempt_count()); |
02b67518 | 1840 | } |
4fd27358 | 1841 | #endif /* UNUSED */ |
02b67518 | 1842 | |
c0a0d0d3 FW |
1843 | #endif /* CONFIG_STACKTRACE */ |
1844 | ||
07d777fe SR |
1845 | /* created for use with alloc_percpu */ |
1846 | struct trace_buffer_struct { | |
1847 | char buffer[TRACE_BUF_SIZE]; | |
1848 | }; | |
1849 | ||
1850 | static struct trace_buffer_struct *trace_percpu_buffer; | |
1851 | static struct trace_buffer_struct *trace_percpu_sirq_buffer; | |
1852 | static struct trace_buffer_struct *trace_percpu_irq_buffer; | |
1853 | static struct trace_buffer_struct *trace_percpu_nmi_buffer; | |
1854 | ||
1855 | /* | |
1856 | * The buffer used is dependent on the context. There is a per cpu | |
1857 | * buffer for normal context, softirq contex, hard irq context and | |
1858 | * for NMI context. Thise allows for lockless recording. | |
1859 | * | |
1860 | * Note, if the buffers failed to be allocated, then this returns NULL | |
1861 | */ | |
1862 | static char *get_trace_buf(void) | |
1863 | { | |
1864 | struct trace_buffer_struct *percpu_buffer; | |
07d777fe SR |
1865 | |
1866 | /* | |
1867 | * If we have allocated per cpu buffers, then we do not | |
1868 | * need to do any locking. | |
1869 | */ | |
1870 | if (in_nmi()) | |
1871 | percpu_buffer = trace_percpu_nmi_buffer; | |
1872 | else if (in_irq()) | |
1873 | percpu_buffer = trace_percpu_irq_buffer; | |
1874 | else if (in_softirq()) | |
1875 | percpu_buffer = trace_percpu_sirq_buffer; | |
1876 | else | |
1877 | percpu_buffer = trace_percpu_buffer; | |
1878 | ||
1879 | if (!percpu_buffer) | |
1880 | return NULL; | |
1881 | ||
d8a0349c | 1882 | return this_cpu_ptr(&percpu_buffer->buffer[0]); |
07d777fe SR |
1883 | } |
1884 | ||
1885 | static int alloc_percpu_trace_buffer(void) | |
1886 | { | |
1887 | struct trace_buffer_struct *buffers; | |
1888 | struct trace_buffer_struct *sirq_buffers; | |
1889 | struct trace_buffer_struct *irq_buffers; | |
1890 | struct trace_buffer_struct *nmi_buffers; | |
1891 | ||
1892 | buffers = alloc_percpu(struct trace_buffer_struct); | |
1893 | if (!buffers) | |
1894 | goto err_warn; | |
1895 | ||
1896 | sirq_buffers = alloc_percpu(struct trace_buffer_struct); | |
1897 | if (!sirq_buffers) | |
1898 | goto err_sirq; | |
1899 | ||
1900 | irq_buffers = alloc_percpu(struct trace_buffer_struct); | |
1901 | if (!irq_buffers) | |
1902 | goto err_irq; | |
1903 | ||
1904 | nmi_buffers = alloc_percpu(struct trace_buffer_struct); | |
1905 | if (!nmi_buffers) | |
1906 | goto err_nmi; | |
1907 | ||
1908 | trace_percpu_buffer = buffers; | |
1909 | trace_percpu_sirq_buffer = sirq_buffers; | |
1910 | trace_percpu_irq_buffer = irq_buffers; | |
1911 | trace_percpu_nmi_buffer = nmi_buffers; | |
1912 | ||
1913 | return 0; | |
1914 | ||
1915 | err_nmi: | |
1916 | free_percpu(irq_buffers); | |
1917 | err_irq: | |
1918 | free_percpu(sirq_buffers); | |
1919 | err_sirq: | |
1920 | free_percpu(buffers); | |
1921 | err_warn: | |
1922 | WARN(1, "Could not allocate percpu trace_printk buffer"); | |
1923 | return -ENOMEM; | |
1924 | } | |
1925 | ||
81698831 SR |
1926 | static int buffers_allocated; |
1927 | ||
07d777fe SR |
1928 | void trace_printk_init_buffers(void) |
1929 | { | |
07d777fe SR |
1930 | if (buffers_allocated) |
1931 | return; | |
1932 | ||
1933 | if (alloc_percpu_trace_buffer()) | |
1934 | return; | |
1935 | ||
1936 | pr_info("ftrace: Allocated trace_printk buffers\n"); | |
1937 | ||
b382ede6 SR |
1938 | /* Expand the buffers to set size */ |
1939 | tracing_update_buffers(); | |
1940 | ||
07d777fe | 1941 | buffers_allocated = 1; |
81698831 SR |
1942 | |
1943 | /* | |
1944 | * trace_printk_init_buffers() can be called by modules. | |
1945 | * If that happens, then we need to start cmdline recording | |
1946 | * directly here. If the global_trace.buffer is already | |
1947 | * allocated here, then this was called by module code. | |
1948 | */ | |
12883efb | 1949 | if (global_trace.trace_buffer.buffer) |
81698831 SR |
1950 | tracing_start_cmdline_record(); |
1951 | } | |
1952 | ||
1953 | void trace_printk_start_comm(void) | |
1954 | { | |
1955 | /* Start tracing comms if trace printk is set */ | |
1956 | if (!buffers_allocated) | |
1957 | return; | |
1958 | tracing_start_cmdline_record(); | |
1959 | } | |
1960 | ||
1961 | static void trace_printk_start_stop_comm(int enabled) | |
1962 | { | |
1963 | if (!buffers_allocated) | |
1964 | return; | |
1965 | ||
1966 | if (enabled) | |
1967 | tracing_start_cmdline_record(); | |
1968 | else | |
1969 | tracing_stop_cmdline_record(); | |
07d777fe SR |
1970 | } |
1971 | ||
769b0441 | 1972 | /** |
48ead020 | 1973 | * trace_vbprintk - write binary msg to tracing buffer |
769b0441 FW |
1974 | * |
1975 | */ | |
40ce74f1 | 1976 | int trace_vbprintk(unsigned long ip, const char *fmt, va_list args) |
769b0441 | 1977 | { |
e1112b4d | 1978 | struct ftrace_event_call *call = &event_bprint; |
769b0441 | 1979 | struct ring_buffer_event *event; |
e77405ad | 1980 | struct ring_buffer *buffer; |
769b0441 | 1981 | struct trace_array *tr = &global_trace; |
48ead020 | 1982 | struct bprint_entry *entry; |
769b0441 | 1983 | unsigned long flags; |
07d777fe SR |
1984 | char *tbuffer; |
1985 | int len = 0, size, pc; | |
769b0441 FW |
1986 | |
1987 | if (unlikely(tracing_selftest_running || tracing_disabled)) | |
1988 | return 0; | |
1989 | ||
1990 | /* Don't pollute graph traces with trace_vprintk internals */ | |
1991 | pause_graph_tracing(); | |
1992 | ||
1993 | pc = preempt_count(); | |
5168ae50 | 1994 | preempt_disable_notrace(); |
769b0441 | 1995 | |
07d777fe SR |
1996 | tbuffer = get_trace_buf(); |
1997 | if (!tbuffer) { | |
1998 | len = 0; | |
769b0441 | 1999 | goto out; |
07d777fe | 2000 | } |
769b0441 | 2001 | |
07d777fe | 2002 | len = vbin_printf((u32 *)tbuffer, TRACE_BUF_SIZE/sizeof(int), fmt, args); |
769b0441 | 2003 | |
07d777fe SR |
2004 | if (len > TRACE_BUF_SIZE/sizeof(int) || len < 0) |
2005 | goto out; | |
769b0441 | 2006 | |
07d777fe | 2007 | local_save_flags(flags); |
769b0441 | 2008 | size = sizeof(*entry) + sizeof(u32) * len; |
12883efb | 2009 | buffer = tr->trace_buffer.buffer; |
e77405ad SR |
2010 | event = trace_buffer_lock_reserve(buffer, TRACE_BPRINT, size, |
2011 | flags, pc); | |
769b0441 | 2012 | if (!event) |
07d777fe | 2013 | goto out; |
769b0441 FW |
2014 | entry = ring_buffer_event_data(event); |
2015 | entry->ip = ip; | |
769b0441 FW |
2016 | entry->fmt = fmt; |
2017 | ||
07d777fe | 2018 | memcpy(entry->buf, tbuffer, sizeof(u32) * len); |
d931369b | 2019 | if (!filter_check_discard(call, entry, buffer, event)) { |
7ffbd48d | 2020 | __buffer_unlock_commit(buffer, event); |
d931369b SR |
2021 | ftrace_trace_stack(buffer, flags, 6, pc); |
2022 | } | |
769b0441 | 2023 | |
769b0441 | 2024 | out: |
5168ae50 | 2025 | preempt_enable_notrace(); |
769b0441 FW |
2026 | unpause_graph_tracing(); |
2027 | ||
2028 | return len; | |
2029 | } | |
48ead020 FW |
2030 | EXPORT_SYMBOL_GPL(trace_vbprintk); |
2031 | ||
12883efb SRRH |
2032 | static int |
2033 | __trace_array_vprintk(struct ring_buffer *buffer, | |
2034 | unsigned long ip, const char *fmt, va_list args) | |
48ead020 | 2035 | { |
e1112b4d | 2036 | struct ftrace_event_call *call = &event_print; |
48ead020 | 2037 | struct ring_buffer_event *event; |
07d777fe | 2038 | int len = 0, size, pc; |
48ead020 | 2039 | struct print_entry *entry; |
07d777fe SR |
2040 | unsigned long flags; |
2041 | char *tbuffer; | |
48ead020 FW |
2042 | |
2043 | if (tracing_disabled || tracing_selftest_running) | |
2044 | return 0; | |
2045 | ||
07d777fe SR |
2046 | /* Don't pollute graph traces with trace_vprintk internals */ |
2047 | pause_graph_tracing(); | |
2048 | ||
48ead020 FW |
2049 | pc = preempt_count(); |
2050 | preempt_disable_notrace(); | |
48ead020 | 2051 | |
07d777fe SR |
2052 | |
2053 | tbuffer = get_trace_buf(); | |
2054 | if (!tbuffer) { | |
2055 | len = 0; | |
48ead020 | 2056 | goto out; |
07d777fe | 2057 | } |
48ead020 | 2058 | |
07d777fe SR |
2059 | len = vsnprintf(tbuffer, TRACE_BUF_SIZE, fmt, args); |
2060 | if (len > TRACE_BUF_SIZE) | |
2061 | goto out; | |
48ead020 | 2062 | |
07d777fe | 2063 | local_save_flags(flags); |
48ead020 | 2064 | size = sizeof(*entry) + len + 1; |
e77405ad | 2065 | event = trace_buffer_lock_reserve(buffer, TRACE_PRINT, size, |
07d777fe | 2066 | flags, pc); |
48ead020 | 2067 | if (!event) |
07d777fe | 2068 | goto out; |
48ead020 | 2069 | entry = ring_buffer_event_data(event); |
c13d2f7c | 2070 | entry->ip = ip; |
48ead020 | 2071 | |
07d777fe | 2072 | memcpy(&entry->buf, tbuffer, len); |
c13d2f7c | 2073 | entry->buf[len] = '\0'; |
d931369b | 2074 | if (!filter_check_discard(call, entry, buffer, event)) { |
7ffbd48d | 2075 | __buffer_unlock_commit(buffer, event); |
07d777fe | 2076 | ftrace_trace_stack(buffer, flags, 6, pc); |
d931369b | 2077 | } |
48ead020 FW |
2078 | out: |
2079 | preempt_enable_notrace(); | |
07d777fe | 2080 | unpause_graph_tracing(); |
48ead020 FW |
2081 | |
2082 | return len; | |
2083 | } | |
659372d3 | 2084 | |
12883efb SRRH |
2085 | int trace_array_vprintk(struct trace_array *tr, |
2086 | unsigned long ip, const char *fmt, va_list args) | |
2087 | { | |
2088 | return __trace_array_vprintk(tr->trace_buffer.buffer, ip, fmt, args); | |
2089 | } | |
2090 | ||
2091 | int trace_array_printk(struct trace_array *tr, | |
2092 | unsigned long ip, const char *fmt, ...) | |
2093 | { | |
2094 | int ret; | |
2095 | va_list ap; | |
2096 | ||
2097 | if (!(trace_flags & TRACE_ITER_PRINTK)) | |
2098 | return 0; | |
2099 | ||
2100 | va_start(ap, fmt); | |
2101 | ret = trace_array_vprintk(tr, ip, fmt, ap); | |
2102 | va_end(ap); | |
2103 | return ret; | |
2104 | } | |
2105 | ||
2106 | int trace_array_printk_buf(struct ring_buffer *buffer, | |
2107 | unsigned long ip, const char *fmt, ...) | |
2108 | { | |
2109 | int ret; | |
2110 | va_list ap; | |
2111 | ||
2112 | if (!(trace_flags & TRACE_ITER_PRINTK)) | |
2113 | return 0; | |
2114 | ||
2115 | va_start(ap, fmt); | |
2116 | ret = __trace_array_vprintk(buffer, ip, fmt, ap); | |
2117 | va_end(ap); | |
2118 | return ret; | |
2119 | } | |
2120 | ||
659372d3 SR |
2121 | int trace_vprintk(unsigned long ip, const char *fmt, va_list args) |
2122 | { | |
a813a159 | 2123 | return trace_array_vprintk(&global_trace, ip, fmt, args); |
659372d3 | 2124 | } |
769b0441 FW |
2125 | EXPORT_SYMBOL_GPL(trace_vprintk); |
2126 | ||
e2ac8ef5 | 2127 | static void trace_iterator_increment(struct trace_iterator *iter) |
5a90f577 | 2128 | { |
6d158a81 SR |
2129 | struct ring_buffer_iter *buf_iter = trace_buffer_iter(iter, iter->cpu); |
2130 | ||
5a90f577 | 2131 | iter->idx++; |
6d158a81 SR |
2132 | if (buf_iter) |
2133 | ring_buffer_read(buf_iter, NULL); | |
5a90f577 SR |
2134 | } |
2135 | ||
e309b41d | 2136 | static struct trace_entry * |
bc21b478 SR |
2137 | peek_next_entry(struct trace_iterator *iter, int cpu, u64 *ts, |
2138 | unsigned long *lost_events) | |
dd0e545f | 2139 | { |
3928a8a2 | 2140 | struct ring_buffer_event *event; |
6d158a81 | 2141 | struct ring_buffer_iter *buf_iter = trace_buffer_iter(iter, cpu); |
dd0e545f | 2142 | |
d769041f SR |
2143 | if (buf_iter) |
2144 | event = ring_buffer_iter_peek(buf_iter, ts); | |
2145 | else | |
12883efb | 2146 | event = ring_buffer_peek(iter->trace_buffer->buffer, cpu, ts, |
bc21b478 | 2147 | lost_events); |
d769041f | 2148 | |
4a9bd3f1 SR |
2149 | if (event) { |
2150 | iter->ent_size = ring_buffer_event_length(event); | |
2151 | return ring_buffer_event_data(event); | |
2152 | } | |
2153 | iter->ent_size = 0; | |
2154 | return NULL; | |
dd0e545f | 2155 | } |
d769041f | 2156 | |
dd0e545f | 2157 | static struct trace_entry * |
bc21b478 SR |
2158 | __find_next_entry(struct trace_iterator *iter, int *ent_cpu, |
2159 | unsigned long *missing_events, u64 *ent_ts) | |
bc0c38d1 | 2160 | { |
12883efb | 2161 | struct ring_buffer *buffer = iter->trace_buffer->buffer; |
bc0c38d1 | 2162 | struct trace_entry *ent, *next = NULL; |
aa27497c | 2163 | unsigned long lost_events = 0, next_lost = 0; |
b04cc6b1 | 2164 | int cpu_file = iter->cpu_file; |
3928a8a2 | 2165 | u64 next_ts = 0, ts; |
bc0c38d1 | 2166 | int next_cpu = -1; |
12b5da34 | 2167 | int next_size = 0; |
bc0c38d1 SR |
2168 | int cpu; |
2169 | ||
b04cc6b1 FW |
2170 | /* |
2171 | * If we are in a per_cpu trace file, don't bother by iterating over | |
2172 | * all cpu and peek directly. | |
2173 | */ | |
ae3b5093 | 2174 | if (cpu_file > RING_BUFFER_ALL_CPUS) { |
b04cc6b1 FW |
2175 | if (ring_buffer_empty_cpu(buffer, cpu_file)) |
2176 | return NULL; | |
bc21b478 | 2177 | ent = peek_next_entry(iter, cpu_file, ent_ts, missing_events); |
b04cc6b1 FW |
2178 | if (ent_cpu) |
2179 | *ent_cpu = cpu_file; | |
2180 | ||
2181 | return ent; | |
2182 | } | |
2183 | ||
ab46428c | 2184 | for_each_tracing_cpu(cpu) { |
dd0e545f | 2185 | |
3928a8a2 SR |
2186 | if (ring_buffer_empty_cpu(buffer, cpu)) |
2187 | continue; | |
dd0e545f | 2188 | |
bc21b478 | 2189 | ent = peek_next_entry(iter, cpu, &ts, &lost_events); |
dd0e545f | 2190 | |
cdd31cd2 IM |
2191 | /* |
2192 | * Pick the entry with the smallest timestamp: | |
2193 | */ | |
3928a8a2 | 2194 | if (ent && (!next || ts < next_ts)) { |
bc0c38d1 SR |
2195 | next = ent; |
2196 | next_cpu = cpu; | |
3928a8a2 | 2197 | next_ts = ts; |
bc21b478 | 2198 | next_lost = lost_events; |
12b5da34 | 2199 | next_size = iter->ent_size; |
bc0c38d1 SR |
2200 | } |
2201 | } | |
2202 | ||
12b5da34 SR |
2203 | iter->ent_size = next_size; |
2204 | ||
bc0c38d1 SR |
2205 | if (ent_cpu) |
2206 | *ent_cpu = next_cpu; | |
2207 | ||
3928a8a2 SR |
2208 | if (ent_ts) |
2209 | *ent_ts = next_ts; | |
2210 | ||
bc21b478 SR |
2211 | if (missing_events) |
2212 | *missing_events = next_lost; | |
2213 | ||
bc0c38d1 SR |
2214 | return next; |
2215 | } | |
2216 | ||
dd0e545f | 2217 | /* Find the next real entry, without updating the iterator itself */ |
c4a8e8be FW |
2218 | struct trace_entry *trace_find_next_entry(struct trace_iterator *iter, |
2219 | int *ent_cpu, u64 *ent_ts) | |
bc0c38d1 | 2220 | { |
bc21b478 | 2221 | return __find_next_entry(iter, ent_cpu, NULL, ent_ts); |
dd0e545f SR |
2222 | } |
2223 | ||
2224 | /* Find the next real entry, and increment the iterator to the next entry */ | |
955b61e5 | 2225 | void *trace_find_next_entry_inc(struct trace_iterator *iter) |
dd0e545f | 2226 | { |
bc21b478 SR |
2227 | iter->ent = __find_next_entry(iter, &iter->cpu, |
2228 | &iter->lost_events, &iter->ts); | |
dd0e545f | 2229 | |
3928a8a2 | 2230 | if (iter->ent) |
e2ac8ef5 | 2231 | trace_iterator_increment(iter); |
dd0e545f | 2232 | |
3928a8a2 | 2233 | return iter->ent ? iter : NULL; |
b3806b43 | 2234 | } |
bc0c38d1 | 2235 | |
e309b41d | 2236 | static void trace_consume(struct trace_iterator *iter) |
b3806b43 | 2237 | { |
12883efb | 2238 | ring_buffer_consume(iter->trace_buffer->buffer, iter->cpu, &iter->ts, |
bc21b478 | 2239 | &iter->lost_events); |
bc0c38d1 SR |
2240 | } |
2241 | ||
e309b41d | 2242 | static void *s_next(struct seq_file *m, void *v, loff_t *pos) |
bc0c38d1 SR |
2243 | { |
2244 | struct trace_iterator *iter = m->private; | |
bc0c38d1 | 2245 | int i = (int)*pos; |
4e3c3333 | 2246 | void *ent; |
bc0c38d1 | 2247 | |
a63ce5b3 SR |
2248 | WARN_ON_ONCE(iter->leftover); |
2249 | ||
bc0c38d1 SR |
2250 | (*pos)++; |
2251 | ||
2252 | /* can't go backwards */ | |
2253 | if (iter->idx > i) | |
2254 | return NULL; | |
2255 | ||
2256 | if (iter->idx < 0) | |
955b61e5 | 2257 | ent = trace_find_next_entry_inc(iter); |
bc0c38d1 SR |
2258 | else |
2259 | ent = iter; | |
2260 | ||
2261 | while (ent && iter->idx < i) | |
955b61e5 | 2262 | ent = trace_find_next_entry_inc(iter); |
bc0c38d1 SR |
2263 | |
2264 | iter->pos = *pos; | |
2265 | ||
bc0c38d1 SR |
2266 | return ent; |
2267 | } | |
2268 | ||
955b61e5 | 2269 | void tracing_iter_reset(struct trace_iterator *iter, int cpu) |
2f26ebd5 | 2270 | { |
2f26ebd5 SR |
2271 | struct ring_buffer_event *event; |
2272 | struct ring_buffer_iter *buf_iter; | |
2273 | unsigned long entries = 0; | |
2274 | u64 ts; | |
2275 | ||
12883efb | 2276 | per_cpu_ptr(iter->trace_buffer->data, cpu)->skipped_entries = 0; |
2f26ebd5 | 2277 | |
6d158a81 SR |
2278 | buf_iter = trace_buffer_iter(iter, cpu); |
2279 | if (!buf_iter) | |
2f26ebd5 SR |
2280 | return; |
2281 | ||
2f26ebd5 SR |
2282 | ring_buffer_iter_reset(buf_iter); |
2283 | ||
2284 | /* | |
2285 | * We could have the case with the max latency tracers | |
2286 | * that a reset never took place on a cpu. This is evident | |
2287 | * by the timestamp being before the start of the buffer. | |
2288 | */ | |
2289 | while ((event = ring_buffer_iter_peek(buf_iter, &ts))) { | |
12883efb | 2290 | if (ts >= iter->trace_buffer->time_start) |
2f26ebd5 SR |
2291 | break; |
2292 | entries++; | |
2293 | ring_buffer_read(buf_iter, NULL); | |
2294 | } | |
2295 | ||
12883efb | 2296 | per_cpu_ptr(iter->trace_buffer->data, cpu)->skipped_entries = entries; |
2f26ebd5 SR |
2297 | } |
2298 | ||
d7350c3f | 2299 | /* |
d7350c3f FW |
2300 | * The current tracer is copied to avoid a global locking |
2301 | * all around. | |
2302 | */ | |
bc0c38d1 SR |
2303 | static void *s_start(struct seq_file *m, loff_t *pos) |
2304 | { | |
2305 | struct trace_iterator *iter = m->private; | |
2b6080f2 | 2306 | struct trace_array *tr = iter->tr; |
b04cc6b1 | 2307 | int cpu_file = iter->cpu_file; |
bc0c38d1 SR |
2308 | void *p = NULL; |
2309 | loff_t l = 0; | |
3928a8a2 | 2310 | int cpu; |
bc0c38d1 | 2311 | |
2fd196ec HT |
2312 | /* |
2313 | * copy the tracer to avoid using a global lock all around. | |
2314 | * iter->trace is a copy of current_trace, the pointer to the | |
2315 | * name may be used instead of a strcmp(), as iter->trace->name | |
2316 | * will point to the same string as current_trace->name. | |
2317 | */ | |
bc0c38d1 | 2318 | mutex_lock(&trace_types_lock); |
2b6080f2 SR |
2319 | if (unlikely(tr->current_trace && iter->trace->name != tr->current_trace->name)) |
2320 | *iter->trace = *tr->current_trace; | |
d7350c3f | 2321 | mutex_unlock(&trace_types_lock); |
bc0c38d1 | 2322 | |
12883efb | 2323 | #ifdef CONFIG_TRACER_MAX_TRACE |
debdd57f HT |
2324 | if (iter->snapshot && iter->trace->use_max_tr) |
2325 | return ERR_PTR(-EBUSY); | |
12883efb | 2326 | #endif |
debdd57f HT |
2327 | |
2328 | if (!iter->snapshot) | |
2329 | atomic_inc(&trace_record_cmdline_disabled); | |
bc0c38d1 | 2330 | |
bc0c38d1 SR |
2331 | if (*pos != iter->pos) { |
2332 | iter->ent = NULL; | |
2333 | iter->cpu = 0; | |
2334 | iter->idx = -1; | |
2335 | ||
ae3b5093 | 2336 | if (cpu_file == RING_BUFFER_ALL_CPUS) { |
b04cc6b1 | 2337 | for_each_tracing_cpu(cpu) |
2f26ebd5 | 2338 | tracing_iter_reset(iter, cpu); |
b04cc6b1 | 2339 | } else |
2f26ebd5 | 2340 | tracing_iter_reset(iter, cpu_file); |
bc0c38d1 | 2341 | |
ac91d854 | 2342 | iter->leftover = 0; |
bc0c38d1 SR |
2343 | for (p = iter; p && l < *pos; p = s_next(m, p, &l)) |
2344 | ; | |
2345 | ||
2346 | } else { | |
a63ce5b3 SR |
2347 | /* |
2348 | * If we overflowed the seq_file before, then we want | |
2349 | * to just reuse the trace_seq buffer again. | |
2350 | */ | |
2351 | if (iter->leftover) | |
2352 | p = iter; | |
2353 | else { | |
2354 | l = *pos - 1; | |
2355 | p = s_next(m, p, &l); | |
2356 | } | |
bc0c38d1 SR |
2357 | } |
2358 | ||
4f535968 | 2359 | trace_event_read_lock(); |
7e53bd42 | 2360 | trace_access_lock(cpu_file); |
bc0c38d1 SR |
2361 | return p; |
2362 | } | |
2363 | ||
2364 | static void s_stop(struct seq_file *m, void *p) | |
2365 | { | |
7e53bd42 LJ |
2366 | struct trace_iterator *iter = m->private; |
2367 | ||
12883efb | 2368 | #ifdef CONFIG_TRACER_MAX_TRACE |
debdd57f HT |
2369 | if (iter->snapshot && iter->trace->use_max_tr) |
2370 | return; | |
12883efb | 2371 | #endif |
debdd57f HT |
2372 | |
2373 | if (!iter->snapshot) | |
2374 | atomic_dec(&trace_record_cmdline_disabled); | |
12883efb | 2375 | |
7e53bd42 | 2376 | trace_access_unlock(iter->cpu_file); |
4f535968 | 2377 | trace_event_read_unlock(); |
bc0c38d1 SR |
2378 | } |
2379 | ||
39eaf7ef | 2380 | static void |
12883efb SRRH |
2381 | get_total_entries(struct trace_buffer *buf, |
2382 | unsigned long *total, unsigned long *entries) | |
39eaf7ef SR |
2383 | { |
2384 | unsigned long count; | |
2385 | int cpu; | |
2386 | ||
2387 | *total = 0; | |
2388 | *entries = 0; | |
2389 | ||
2390 | for_each_tracing_cpu(cpu) { | |
12883efb | 2391 | count = ring_buffer_entries_cpu(buf->buffer, cpu); |
39eaf7ef SR |
2392 | /* |
2393 | * If this buffer has skipped entries, then we hold all | |
2394 | * entries for the trace and we need to ignore the | |
2395 | * ones before the time stamp. | |
2396 | */ | |
12883efb SRRH |
2397 | if (per_cpu_ptr(buf->data, cpu)->skipped_entries) { |
2398 | count -= per_cpu_ptr(buf->data, cpu)->skipped_entries; | |
39eaf7ef SR |
2399 | /* total is the same as the entries */ |
2400 | *total += count; | |
2401 | } else | |
2402 | *total += count + | |
12883efb | 2403 | ring_buffer_overrun_cpu(buf->buffer, cpu); |
39eaf7ef SR |
2404 | *entries += count; |
2405 | } | |
2406 | } | |
2407 | ||
e309b41d | 2408 | static void print_lat_help_header(struct seq_file *m) |
bc0c38d1 | 2409 | { |
a6168353 ME |
2410 | seq_puts(m, "# _------=> CPU# \n"); |
2411 | seq_puts(m, "# / _-----=> irqs-off \n"); | |
2412 | seq_puts(m, "# | / _----=> need-resched \n"); | |
2413 | seq_puts(m, "# || / _---=> hardirq/softirq \n"); | |
2414 | seq_puts(m, "# ||| / _--=> preempt-depth \n"); | |
e6e1e259 SR |
2415 | seq_puts(m, "# |||| / delay \n"); |
2416 | seq_puts(m, "# cmd pid ||||| time | caller \n"); | |
2417 | seq_puts(m, "# \\ / ||||| \\ | / \n"); | |
bc0c38d1 SR |
2418 | } |
2419 | ||
12883efb | 2420 | static void print_event_info(struct trace_buffer *buf, struct seq_file *m) |
bc0c38d1 | 2421 | { |
39eaf7ef SR |
2422 | unsigned long total; |
2423 | unsigned long entries; | |
2424 | ||
12883efb | 2425 | get_total_entries(buf, &total, &entries); |
39eaf7ef SR |
2426 | seq_printf(m, "# entries-in-buffer/entries-written: %lu/%lu #P:%d\n", |
2427 | entries, total, num_online_cpus()); | |
2428 | seq_puts(m, "#\n"); | |
2429 | } | |
2430 | ||
12883efb | 2431 | static void print_func_help_header(struct trace_buffer *buf, struct seq_file *m) |
39eaf7ef | 2432 | { |
12883efb | 2433 | print_event_info(buf, m); |
77271ce4 | 2434 | seq_puts(m, "# TASK-PID CPU# TIMESTAMP FUNCTION\n"); |
a6168353 | 2435 | seq_puts(m, "# | | | | |\n"); |
bc0c38d1 SR |
2436 | } |
2437 | ||
12883efb | 2438 | static void print_func_help_header_irq(struct trace_buffer *buf, struct seq_file *m) |
77271ce4 | 2439 | { |
12883efb | 2440 | print_event_info(buf, m); |
77271ce4 SR |
2441 | seq_puts(m, "# _-----=> irqs-off\n"); |
2442 | seq_puts(m, "# / _----=> need-resched\n"); | |
2443 | seq_puts(m, "# | / _---=> hardirq/softirq\n"); | |
2444 | seq_puts(m, "# || / _--=> preempt-depth\n"); | |
2445 | seq_puts(m, "# ||| / delay\n"); | |
2446 | seq_puts(m, "# TASK-PID CPU# |||| TIMESTAMP FUNCTION\n"); | |
2447 | seq_puts(m, "# | | | |||| | |\n"); | |
2448 | } | |
bc0c38d1 | 2449 | |
62b915f1 | 2450 | void |
bc0c38d1 SR |
2451 | print_trace_header(struct seq_file *m, struct trace_iterator *iter) |
2452 | { | |
2453 | unsigned long sym_flags = (trace_flags & TRACE_ITER_SYM_MASK); | |
12883efb SRRH |
2454 | struct trace_buffer *buf = iter->trace_buffer; |
2455 | struct trace_array_cpu *data = per_cpu_ptr(buf->data, buf->cpu); | |
2b6080f2 | 2456 | struct tracer *type = iter->trace; |
39eaf7ef SR |
2457 | unsigned long entries; |
2458 | unsigned long total; | |
bc0c38d1 SR |
2459 | const char *name = "preemption"; |
2460 | ||
d840f718 | 2461 | name = type->name; |
bc0c38d1 | 2462 | |
12883efb | 2463 | get_total_entries(buf, &total, &entries); |
bc0c38d1 | 2464 | |
888b55dc | 2465 | seq_printf(m, "# %s latency trace v1.1.5 on %s\n", |
bc0c38d1 | 2466 | name, UTS_RELEASE); |
888b55dc | 2467 | seq_puts(m, "# -----------------------------------" |
bc0c38d1 | 2468 | "---------------------------------\n"); |
888b55dc | 2469 | seq_printf(m, "# latency: %lu us, #%lu/%lu, CPU#%d |" |
bc0c38d1 | 2470 | " (M:%s VP:%d, KP:%d, SP:%d HP:%d", |
57f50be1 | 2471 | nsecs_to_usecs(data->saved_latency), |
bc0c38d1 | 2472 | entries, |
4c11d7ae | 2473 | total, |
12883efb | 2474 | buf->cpu, |
bc0c38d1 SR |
2475 | #if defined(CONFIG_PREEMPT_NONE) |
2476 | "server", | |
2477 | #elif defined(CONFIG_PREEMPT_VOLUNTARY) | |
2478 | "desktop", | |
b5c21b45 | 2479 | #elif defined(CONFIG_PREEMPT) |
bc0c38d1 SR |
2480 | "preempt", |
2481 | #else | |
2482 | "unknown", | |
2483 | #endif | |
2484 | /* These are reserved for later use */ | |
2485 | 0, 0, 0, 0); | |
2486 | #ifdef CONFIG_SMP | |
2487 | seq_printf(m, " #P:%d)\n", num_online_cpus()); | |
2488 | #else | |
2489 | seq_puts(m, ")\n"); | |
2490 | #endif | |
888b55dc KM |
2491 | seq_puts(m, "# -----------------\n"); |
2492 | seq_printf(m, "# | task: %.16s-%d " | |
bc0c38d1 | 2493 | "(uid:%d nice:%ld policy:%ld rt_prio:%ld)\n", |
d20b92ab EB |
2494 | data->comm, data->pid, |
2495 | from_kuid_munged(seq_user_ns(m), data->uid), data->nice, | |
bc0c38d1 | 2496 | data->policy, data->rt_priority); |
888b55dc | 2497 | seq_puts(m, "# -----------------\n"); |
bc0c38d1 SR |
2498 | |
2499 | if (data->critical_start) { | |
888b55dc | 2500 | seq_puts(m, "# => started at: "); |
214023c3 SR |
2501 | seq_print_ip_sym(&iter->seq, data->critical_start, sym_flags); |
2502 | trace_print_seq(m, &iter->seq); | |
888b55dc | 2503 | seq_puts(m, "\n# => ended at: "); |
214023c3 SR |
2504 | seq_print_ip_sym(&iter->seq, data->critical_end, sym_flags); |
2505 | trace_print_seq(m, &iter->seq); | |
8248ac05 | 2506 | seq_puts(m, "\n#\n"); |
bc0c38d1 SR |
2507 | } |
2508 | ||
888b55dc | 2509 | seq_puts(m, "#\n"); |
bc0c38d1 SR |
2510 | } |
2511 | ||
a309720c SR |
2512 | static void test_cpu_buff_start(struct trace_iterator *iter) |
2513 | { | |
2514 | struct trace_seq *s = &iter->seq; | |
2515 | ||
12ef7d44 SR |
2516 | if (!(trace_flags & TRACE_ITER_ANNOTATE)) |
2517 | return; | |
2518 | ||
2519 | if (!(iter->iter_flags & TRACE_FILE_ANNOTATE)) | |
2520 | return; | |
2521 | ||
4462344e | 2522 | if (cpumask_test_cpu(iter->cpu, iter->started)) |
a309720c SR |
2523 | return; |
2524 | ||
12883efb | 2525 | if (per_cpu_ptr(iter->trace_buffer->data, iter->cpu)->skipped_entries) |
2f26ebd5 SR |
2526 | return; |
2527 | ||
4462344e | 2528 | cpumask_set_cpu(iter->cpu, iter->started); |
b0dfa978 FW |
2529 | |
2530 | /* Don't print started cpu buffer for the first entry of the trace */ | |
2531 | if (iter->idx > 1) | |
2532 | trace_seq_printf(s, "##### CPU %u buffer started ####\n", | |
2533 | iter->cpu); | |
a309720c SR |
2534 | } |
2535 | ||
2c4f035f | 2536 | static enum print_line_t print_trace_fmt(struct trace_iterator *iter) |
bc0c38d1 | 2537 | { |
214023c3 | 2538 | struct trace_seq *s = &iter->seq; |
bc0c38d1 | 2539 | unsigned long sym_flags = (trace_flags & TRACE_ITER_SYM_MASK); |
4e3c3333 | 2540 | struct trace_entry *entry; |
f633cef0 | 2541 | struct trace_event *event; |
bc0c38d1 | 2542 | |
4e3c3333 | 2543 | entry = iter->ent; |
dd0e545f | 2544 | |
a309720c SR |
2545 | test_cpu_buff_start(iter); |
2546 | ||
c4a8e8be | 2547 | event = ftrace_find_event(entry->type); |
bc0c38d1 | 2548 | |
c4a8e8be | 2549 | if (trace_flags & TRACE_ITER_CONTEXT_INFO) { |
27d48be8 SR |
2550 | if (iter->iter_flags & TRACE_FILE_LAT_FMT) { |
2551 | if (!trace_print_lat_context(iter)) | |
2552 | goto partial; | |
2553 | } else { | |
2554 | if (!trace_print_context(iter)) | |
2555 | goto partial; | |
2556 | } | |
c4a8e8be | 2557 | } |
bc0c38d1 | 2558 | |
268ccda0 | 2559 | if (event) |
a9a57763 | 2560 | return event->funcs->trace(iter, sym_flags, event); |
d9793bd8 ACM |
2561 | |
2562 | if (!trace_seq_printf(s, "Unknown type %d\n", entry->type)) | |
2563 | goto partial; | |
02b67518 | 2564 | |
2c4f035f | 2565 | return TRACE_TYPE_HANDLED; |
d9793bd8 ACM |
2566 | partial: |
2567 | return TRACE_TYPE_PARTIAL_LINE; | |
bc0c38d1 SR |
2568 | } |
2569 | ||
2c4f035f | 2570 | static enum print_line_t print_raw_fmt(struct trace_iterator *iter) |
f9896bf3 IM |
2571 | { |
2572 | struct trace_seq *s = &iter->seq; | |
2573 | struct trace_entry *entry; | |
f633cef0 | 2574 | struct trace_event *event; |
f9896bf3 IM |
2575 | |
2576 | entry = iter->ent; | |
dd0e545f | 2577 | |
c4a8e8be | 2578 | if (trace_flags & TRACE_ITER_CONTEXT_INFO) { |
d9793bd8 ACM |
2579 | if (!trace_seq_printf(s, "%d %d %llu ", |
2580 | entry->pid, iter->cpu, iter->ts)) | |
2581 | goto partial; | |
c4a8e8be | 2582 | } |
f9896bf3 | 2583 | |
f633cef0 | 2584 | event = ftrace_find_event(entry->type); |
268ccda0 | 2585 | if (event) |
a9a57763 | 2586 | return event->funcs->raw(iter, 0, event); |
d9793bd8 ACM |
2587 | |
2588 | if (!trace_seq_printf(s, "%d ?\n", entry->type)) | |
2589 | goto partial; | |
777e208d | 2590 | |
2c4f035f | 2591 | return TRACE_TYPE_HANDLED; |
d9793bd8 ACM |
2592 | partial: |
2593 | return TRACE_TYPE_PARTIAL_LINE; | |
f9896bf3 IM |
2594 | } |
2595 | ||
2c4f035f | 2596 | static enum print_line_t print_hex_fmt(struct trace_iterator *iter) |
5e3ca0ec IM |
2597 | { |
2598 | struct trace_seq *s = &iter->seq; | |
2599 | unsigned char newline = '\n'; | |
2600 | struct trace_entry *entry; | |
f633cef0 | 2601 | struct trace_event *event; |
5e3ca0ec IM |
2602 | |
2603 | entry = iter->ent; | |
dd0e545f | 2604 | |
c4a8e8be FW |
2605 | if (trace_flags & TRACE_ITER_CONTEXT_INFO) { |
2606 | SEQ_PUT_HEX_FIELD_RET(s, entry->pid); | |
2607 | SEQ_PUT_HEX_FIELD_RET(s, iter->cpu); | |
2608 | SEQ_PUT_HEX_FIELD_RET(s, iter->ts); | |
2609 | } | |
5e3ca0ec | 2610 | |
f633cef0 | 2611 | event = ftrace_find_event(entry->type); |
268ccda0 | 2612 | if (event) { |
a9a57763 | 2613 | enum print_line_t ret = event->funcs->hex(iter, 0, event); |
d9793bd8 ACM |
2614 | if (ret != TRACE_TYPE_HANDLED) |
2615 | return ret; | |
2616 | } | |
7104f300 | 2617 | |
5e3ca0ec IM |
2618 | SEQ_PUT_FIELD_RET(s, newline); |
2619 | ||
2c4f035f | 2620 | return TRACE_TYPE_HANDLED; |
5e3ca0ec IM |
2621 | } |
2622 | ||
2c4f035f | 2623 | static enum print_line_t print_bin_fmt(struct trace_iterator *iter) |
cb0f12aa IM |
2624 | { |
2625 | struct trace_seq *s = &iter->seq; | |
2626 | struct trace_entry *entry; | |
f633cef0 | 2627 | struct trace_event *event; |
cb0f12aa IM |
2628 | |
2629 | entry = iter->ent; | |
dd0e545f | 2630 | |
c4a8e8be FW |
2631 | if (trace_flags & TRACE_ITER_CONTEXT_INFO) { |
2632 | SEQ_PUT_FIELD_RET(s, entry->pid); | |
1830b52d | 2633 | SEQ_PUT_FIELD_RET(s, iter->cpu); |
c4a8e8be FW |
2634 | SEQ_PUT_FIELD_RET(s, iter->ts); |
2635 | } | |
cb0f12aa | 2636 | |
f633cef0 | 2637 | event = ftrace_find_event(entry->type); |
a9a57763 SR |
2638 | return event ? event->funcs->binary(iter, 0, event) : |
2639 | TRACE_TYPE_HANDLED; | |
cb0f12aa IM |
2640 | } |
2641 | ||
62b915f1 | 2642 | int trace_empty(struct trace_iterator *iter) |
bc0c38d1 | 2643 | { |
6d158a81 | 2644 | struct ring_buffer_iter *buf_iter; |
bc0c38d1 SR |
2645 | int cpu; |
2646 | ||
9aba60fe | 2647 | /* If we are looking at one CPU buffer, only check that one */ |
ae3b5093 | 2648 | if (iter->cpu_file != RING_BUFFER_ALL_CPUS) { |
9aba60fe | 2649 | cpu = iter->cpu_file; |
6d158a81 SR |
2650 | buf_iter = trace_buffer_iter(iter, cpu); |
2651 | if (buf_iter) { | |
2652 | if (!ring_buffer_iter_empty(buf_iter)) | |
9aba60fe SR |
2653 | return 0; |
2654 | } else { | |
12883efb | 2655 | if (!ring_buffer_empty_cpu(iter->trace_buffer->buffer, cpu)) |
9aba60fe SR |
2656 | return 0; |
2657 | } | |
2658 | return 1; | |
2659 | } | |
2660 | ||
ab46428c | 2661 | for_each_tracing_cpu(cpu) { |
6d158a81 SR |
2662 | buf_iter = trace_buffer_iter(iter, cpu); |
2663 | if (buf_iter) { | |
2664 | if (!ring_buffer_iter_empty(buf_iter)) | |
d769041f SR |
2665 | return 0; |
2666 | } else { | |
12883efb | 2667 | if (!ring_buffer_empty_cpu(iter->trace_buffer->buffer, cpu)) |
d769041f SR |
2668 | return 0; |
2669 | } | |
bc0c38d1 | 2670 | } |
d769041f | 2671 | |
797d3712 | 2672 | return 1; |
bc0c38d1 SR |
2673 | } |
2674 | ||
4f535968 | 2675 | /* Called with trace_event_read_lock() held. */ |
955b61e5 | 2676 | enum print_line_t print_trace_line(struct trace_iterator *iter) |
f9896bf3 | 2677 | { |
2c4f035f FW |
2678 | enum print_line_t ret; |
2679 | ||
ee5e51f5 JO |
2680 | if (iter->lost_events && |
2681 | !trace_seq_printf(&iter->seq, "CPU:%d [LOST %lu EVENTS]\n", | |
2682 | iter->cpu, iter->lost_events)) | |
2683 | return TRACE_TYPE_PARTIAL_LINE; | |
bc21b478 | 2684 | |
2c4f035f FW |
2685 | if (iter->trace && iter->trace->print_line) { |
2686 | ret = iter->trace->print_line(iter); | |
2687 | if (ret != TRACE_TYPE_UNHANDLED) | |
2688 | return ret; | |
2689 | } | |
72829bc3 | 2690 | |
09ae7234 SRRH |
2691 | if (iter->ent->type == TRACE_BPUTS && |
2692 | trace_flags & TRACE_ITER_PRINTK && | |
2693 | trace_flags & TRACE_ITER_PRINTK_MSGONLY) | |
2694 | return trace_print_bputs_msg_only(iter); | |
2695 | ||
48ead020 FW |
2696 | if (iter->ent->type == TRACE_BPRINT && |
2697 | trace_flags & TRACE_ITER_PRINTK && | |
2698 | trace_flags & TRACE_ITER_PRINTK_MSGONLY) | |
5ef841f6 | 2699 | return trace_print_bprintk_msg_only(iter); |
48ead020 | 2700 | |
66896a85 FW |
2701 | if (iter->ent->type == TRACE_PRINT && |
2702 | trace_flags & TRACE_ITER_PRINTK && | |
2703 | trace_flags & TRACE_ITER_PRINTK_MSGONLY) | |
5ef841f6 | 2704 | return trace_print_printk_msg_only(iter); |
66896a85 | 2705 | |
cb0f12aa IM |
2706 | if (trace_flags & TRACE_ITER_BIN) |
2707 | return print_bin_fmt(iter); | |
2708 | ||
5e3ca0ec IM |
2709 | if (trace_flags & TRACE_ITER_HEX) |
2710 | return print_hex_fmt(iter); | |
2711 | ||
f9896bf3 IM |
2712 | if (trace_flags & TRACE_ITER_RAW) |
2713 | return print_raw_fmt(iter); | |
2714 | ||
f9896bf3 IM |
2715 | return print_trace_fmt(iter); |
2716 | } | |
2717 | ||
7e9a49ef JO |
2718 | void trace_latency_header(struct seq_file *m) |
2719 | { | |
2720 | struct trace_iterator *iter = m->private; | |
2721 | ||
2722 | /* print nothing if the buffers are empty */ | |
2723 | if (trace_empty(iter)) | |
2724 | return; | |
2725 | ||
2726 | if (iter->iter_flags & TRACE_FILE_LAT_FMT) | |
2727 | print_trace_header(m, iter); | |
2728 | ||
2729 | if (!(trace_flags & TRACE_ITER_VERBOSE)) | |
2730 | print_lat_help_header(m); | |
2731 | } | |
2732 | ||
62b915f1 JO |
2733 | void trace_default_header(struct seq_file *m) |
2734 | { | |
2735 | struct trace_iterator *iter = m->private; | |
2736 | ||
f56e7f8e JO |
2737 | if (!(trace_flags & TRACE_ITER_CONTEXT_INFO)) |
2738 | return; | |
2739 | ||
62b915f1 JO |
2740 | if (iter->iter_flags & TRACE_FILE_LAT_FMT) { |
2741 | /* print nothing if the buffers are empty */ | |
2742 | if (trace_empty(iter)) | |
2743 | return; | |
2744 | print_trace_header(m, iter); | |
2745 | if (!(trace_flags & TRACE_ITER_VERBOSE)) | |
2746 | print_lat_help_header(m); | |
2747 | } else { | |
77271ce4 SR |
2748 | if (!(trace_flags & TRACE_ITER_VERBOSE)) { |
2749 | if (trace_flags & TRACE_ITER_IRQ_INFO) | |
12883efb | 2750 | print_func_help_header_irq(iter->trace_buffer, m); |
77271ce4 | 2751 | else |
12883efb | 2752 | print_func_help_header(iter->trace_buffer, m); |
77271ce4 | 2753 | } |
62b915f1 JO |
2754 | } |
2755 | } | |
2756 | ||
e0a413f6 SR |
2757 | static void test_ftrace_alive(struct seq_file *m) |
2758 | { | |
2759 | if (!ftrace_is_dead()) | |
2760 | return; | |
2761 | seq_printf(m, "# WARNING: FUNCTION TRACING IS CORRUPTED\n"); | |
2762 | seq_printf(m, "# MAY BE MISSING FUNCTION EVENTS\n"); | |
2763 | } | |
2764 | ||
d8741e2e | 2765 | #ifdef CONFIG_TRACER_MAX_TRACE |
f1affcaa | 2766 | static void show_snapshot_main_help(struct seq_file *m) |
d8741e2e | 2767 | { |
d8741e2e SRRH |
2768 | seq_printf(m, "# echo 0 > snapshot : Clears and frees snapshot buffer\n"); |
2769 | seq_printf(m, "# echo 1 > snapshot : Allocates snapshot buffer, if not already allocated.\n"); | |
2770 | seq_printf(m, "# Takes a snapshot of the main buffer.\n"); | |
2771 | seq_printf(m, "# echo 2 > snapshot : Clears snapshot buffer (but does not allocate)\n"); | |
2772 | seq_printf(m, "# (Doesn't have to be '2' works with any number that\n"); | |
2773 | seq_printf(m, "# is not a '0' or '1')\n"); | |
2774 | } | |
f1affcaa SRRH |
2775 | |
2776 | static void show_snapshot_percpu_help(struct seq_file *m) | |
2777 | { | |
2778 | seq_printf(m, "# echo 0 > snapshot : Invalid for per_cpu snapshot file.\n"); | |
2779 | #ifdef CONFIG_RING_BUFFER_ALLOW_SWAP | |
2780 | seq_printf(m, "# echo 1 > snapshot : Allocates snapshot buffer, if not already allocated.\n"); | |
2781 | seq_printf(m, "# Takes a snapshot of the main buffer for this cpu.\n"); | |
2782 | #else | |
2783 | seq_printf(m, "# echo 1 > snapshot : Not supported with this kernel.\n"); | |
2784 | seq_printf(m, "# Must use main snapshot file to allocate.\n"); | |
2785 | #endif | |
2786 | seq_printf(m, "# echo 2 > snapshot : Clears this cpu's snapshot buffer (but does not allocate)\n"); | |
2787 | seq_printf(m, "# (Doesn't have to be '2' works with any number that\n"); | |
2788 | seq_printf(m, "# is not a '0' or '1')\n"); | |
2789 | } | |
2790 | ||
d8741e2e SRRH |
2791 | static void print_snapshot_help(struct seq_file *m, struct trace_iterator *iter) |
2792 | { | |
45ad21ca | 2793 | if (iter->tr->allocated_snapshot) |
d8741e2e SRRH |
2794 | seq_printf(m, "#\n# * Snapshot is allocated *\n#\n"); |
2795 | else | |
2796 | seq_printf(m, "#\n# * Snapshot is freed *\n#\n"); | |
2797 | ||
2798 | seq_printf(m, "# Snapshot commands:\n"); | |
f1affcaa SRRH |
2799 | if (iter->cpu_file == RING_BUFFER_ALL_CPUS) |
2800 | show_snapshot_main_help(m); | |
2801 | else | |
2802 | show_snapshot_percpu_help(m); | |
d8741e2e SRRH |
2803 | } |
2804 | #else | |
2805 | /* Should never be called */ | |
2806 | static inline void print_snapshot_help(struct seq_file *m, struct trace_iterator *iter) { } | |
2807 | #endif | |
2808 | ||
bc0c38d1 SR |
2809 | static int s_show(struct seq_file *m, void *v) |
2810 | { | |
2811 | struct trace_iterator *iter = v; | |
a63ce5b3 | 2812 | int ret; |
bc0c38d1 SR |
2813 | |
2814 | if (iter->ent == NULL) { | |
2815 | if (iter->tr) { | |
2816 | seq_printf(m, "# tracer: %s\n", iter->trace->name); | |
2817 | seq_puts(m, "#\n"); | |
e0a413f6 | 2818 | test_ftrace_alive(m); |
bc0c38d1 | 2819 | } |
d8741e2e SRRH |
2820 | if (iter->snapshot && trace_empty(iter)) |
2821 | print_snapshot_help(m, iter); | |
2822 | else if (iter->trace && iter->trace->print_header) | |
8bba1bf5 | 2823 | iter->trace->print_header(m); |
62b915f1 JO |
2824 | else |
2825 | trace_default_header(m); | |
2826 | ||
a63ce5b3 SR |
2827 | } else if (iter->leftover) { |
2828 | /* | |
2829 | * If we filled the seq_file buffer earlier, we | |
2830 | * want to just show it now. | |
2831 | */ | |
2832 | ret = trace_print_seq(m, &iter->seq); | |
2833 | ||
2834 | /* ret should this time be zero, but you never know */ | |
2835 | iter->leftover = ret; | |
2836 | ||
bc0c38d1 | 2837 | } else { |
f9896bf3 | 2838 | print_trace_line(iter); |
a63ce5b3 SR |
2839 | ret = trace_print_seq(m, &iter->seq); |
2840 | /* | |
2841 | * If we overflow the seq_file buffer, then it will | |
2842 | * ask us for this data again at start up. | |
2843 | * Use that instead. | |
2844 | * ret is 0 if seq_file write succeeded. | |
2845 | * -1 otherwise. | |
2846 | */ | |
2847 | iter->leftover = ret; | |
bc0c38d1 SR |
2848 | } |
2849 | ||
2850 | return 0; | |
2851 | } | |
2852 | ||
e2d4dbe0 ON |
2853 | /* |
2854 | * Should be used after trace_array_get(), trace_types_lock | |
2855 | * ensures that i_cdev was already initialized. | |
2856 | */ | |
2857 | static inline int tracing_get_cpu(struct inode *inode) | |
2858 | { | |
2859 | if (inode->i_cdev) /* See trace_create_cpu_file() */ | |
2860 | return (long)inode->i_cdev - 1; | |
2861 | return RING_BUFFER_ALL_CPUS; | |
2862 | } | |
2863 | ||
88e9d34c | 2864 | static const struct seq_operations tracer_seq_ops = { |
4bf39a94 IM |
2865 | .start = s_start, |
2866 | .next = s_next, | |
2867 | .stop = s_stop, | |
2868 | .show = s_show, | |
bc0c38d1 SR |
2869 | }; |
2870 | ||
e309b41d | 2871 | static struct trace_iterator * |
7272711a | 2872 | __tracing_open(struct inode *inode, struct file *file, bool snapshot) |
bc0c38d1 | 2873 | { |
7272711a | 2874 | struct trace_array *tr = inode->i_private; |
bc0c38d1 | 2875 | struct trace_iterator *iter; |
50e18b94 | 2876 | int cpu; |
bc0c38d1 | 2877 | |
85a2f9b4 SR |
2878 | if (tracing_disabled) |
2879 | return ERR_PTR(-ENODEV); | |
60a11774 | 2880 | |
50e18b94 | 2881 | iter = __seq_open_private(file, &tracer_seq_ops, sizeof(*iter)); |
85a2f9b4 SR |
2882 | if (!iter) |
2883 | return ERR_PTR(-ENOMEM); | |
bc0c38d1 | 2884 | |
6d158a81 SR |
2885 | iter->buffer_iter = kzalloc(sizeof(*iter->buffer_iter) * num_possible_cpus(), |
2886 | GFP_KERNEL); | |
93574fcc DC |
2887 | if (!iter->buffer_iter) |
2888 | goto release; | |
2889 | ||
d7350c3f FW |
2890 | /* |
2891 | * We make a copy of the current tracer to avoid concurrent | |
2892 | * changes on it while we are reading. | |
2893 | */ | |
bc0c38d1 | 2894 | mutex_lock(&trace_types_lock); |
d7350c3f | 2895 | iter->trace = kzalloc(sizeof(*iter->trace), GFP_KERNEL); |
85a2f9b4 | 2896 | if (!iter->trace) |
d7350c3f | 2897 | goto fail; |
85a2f9b4 | 2898 | |
2b6080f2 | 2899 | *iter->trace = *tr->current_trace; |
d7350c3f | 2900 | |
79f55997 | 2901 | if (!zalloc_cpumask_var(&iter->started, GFP_KERNEL)) |
b0dfa978 FW |
2902 | goto fail; |
2903 | ||
12883efb SRRH |
2904 | iter->tr = tr; |
2905 | ||
2906 | #ifdef CONFIG_TRACER_MAX_TRACE | |
2b6080f2 SR |
2907 | /* Currently only the top directory has a snapshot */ |
2908 | if (tr->current_trace->print_max || snapshot) | |
12883efb | 2909 | iter->trace_buffer = &tr->max_buffer; |
bc0c38d1 | 2910 | else |
12883efb SRRH |
2911 | #endif |
2912 | iter->trace_buffer = &tr->trace_buffer; | |
debdd57f | 2913 | iter->snapshot = snapshot; |
bc0c38d1 | 2914 | iter->pos = -1; |
7272711a | 2915 | iter->cpu_file = tracing_get_cpu(inode); |
d7350c3f | 2916 | mutex_init(&iter->mutex); |
bc0c38d1 | 2917 | |
8bba1bf5 MM |
2918 | /* Notify the tracer early; before we stop tracing. */ |
2919 | if (iter->trace && iter->trace->open) | |
a93751ca | 2920 | iter->trace->open(iter); |
8bba1bf5 | 2921 | |
12ef7d44 | 2922 | /* Annotate start of buffers if we had overruns */ |
12883efb | 2923 | if (ring_buffer_overruns(iter->trace_buffer->buffer)) |
12ef7d44 SR |
2924 | iter->iter_flags |= TRACE_FILE_ANNOTATE; |
2925 | ||
8be0709f | 2926 | /* Output in nanoseconds only if we are using a clock in nanoseconds. */ |
58e8eedf | 2927 | if (trace_clocks[tr->clock_id].in_ns) |
8be0709f DS |
2928 | iter->iter_flags |= TRACE_FILE_TIME_IN_NS; |
2929 | ||
debdd57f HT |
2930 | /* stop the trace while dumping if we are not opening "snapshot" */ |
2931 | if (!iter->snapshot) | |
2b6080f2 | 2932 | tracing_stop_tr(tr); |
2f26ebd5 | 2933 | |
ae3b5093 | 2934 | if (iter->cpu_file == RING_BUFFER_ALL_CPUS) { |
b04cc6b1 | 2935 | for_each_tracing_cpu(cpu) { |
b04cc6b1 | 2936 | iter->buffer_iter[cpu] = |
12883efb | 2937 | ring_buffer_read_prepare(iter->trace_buffer->buffer, cpu); |
72c9ddfd DM |
2938 | } |
2939 | ring_buffer_read_prepare_sync(); | |
2940 | for_each_tracing_cpu(cpu) { | |
2941 | ring_buffer_read_start(iter->buffer_iter[cpu]); | |
2f26ebd5 | 2942 | tracing_iter_reset(iter, cpu); |
b04cc6b1 FW |
2943 | } |
2944 | } else { | |
2945 | cpu = iter->cpu_file; | |
3928a8a2 | 2946 | iter->buffer_iter[cpu] = |
12883efb | 2947 | ring_buffer_read_prepare(iter->trace_buffer->buffer, cpu); |
72c9ddfd DM |
2948 | ring_buffer_read_prepare_sync(); |
2949 | ring_buffer_read_start(iter->buffer_iter[cpu]); | |
2f26ebd5 | 2950 | tracing_iter_reset(iter, cpu); |
3928a8a2 SR |
2951 | } |
2952 | ||
bc0c38d1 SR |
2953 | mutex_unlock(&trace_types_lock); |
2954 | ||
bc0c38d1 | 2955 | return iter; |
3928a8a2 | 2956 | |
d7350c3f | 2957 | fail: |
3928a8a2 | 2958 | mutex_unlock(&trace_types_lock); |
d7350c3f | 2959 | kfree(iter->trace); |
6d158a81 | 2960 | kfree(iter->buffer_iter); |
93574fcc | 2961 | release: |
50e18b94 JO |
2962 | seq_release_private(inode, file); |
2963 | return ERR_PTR(-ENOMEM); | |
bc0c38d1 SR |
2964 | } |
2965 | ||
2966 | int tracing_open_generic(struct inode *inode, struct file *filp) | |
2967 | { | |
60a11774 SR |
2968 | if (tracing_disabled) |
2969 | return -ENODEV; | |
2970 | ||
bc0c38d1 SR |
2971 | filp->private_data = inode->i_private; |
2972 | return 0; | |
2973 | } | |
2974 | ||
6492334c SRRH |
2975 | /* |
2976 | * Open and update trace_array ref count. | |
2977 | * Must have the current trace_array passed to it. | |
2978 | */ | |
2979 | int tracing_open_generic_tr(struct inode *inode, struct file *filp) | |
2980 | { | |
2981 | struct trace_array *tr = inode->i_private; | |
2982 | ||
2983 | if (tracing_disabled) | |
2984 | return -ENODEV; | |
2985 | ||
2986 | if (trace_array_get(tr) < 0) | |
2987 | return -ENODEV; | |
2988 | ||
2989 | filp->private_data = inode->i_private; | |
2990 | ||
2991 | return 0; | |
6492334c SRRH |
2992 | } |
2993 | ||
4fd27358 | 2994 | static int tracing_release(struct inode *inode, struct file *file) |
bc0c38d1 | 2995 | { |
7272711a | 2996 | struct trace_array *tr = inode->i_private; |
907f2784 | 2997 | struct seq_file *m = file->private_data; |
4acd4d00 | 2998 | struct trace_iterator *iter; |
3928a8a2 | 2999 | int cpu; |
bc0c38d1 | 3000 | |
59d8f488 | 3001 | if (!(file->f_mode & FMODE_READ)) { |
7272711a | 3002 | trace_array_put(tr); |
4acd4d00 | 3003 | return 0; |
59d8f488 | 3004 | } |
4acd4d00 | 3005 | |
7272711a | 3006 | /* Writes do not use seq_file */ |
4acd4d00 | 3007 | iter = m->private; |
bc0c38d1 | 3008 | mutex_lock(&trace_types_lock); |
a695cb58 | 3009 | |
3928a8a2 SR |
3010 | for_each_tracing_cpu(cpu) { |
3011 | if (iter->buffer_iter[cpu]) | |
3012 | ring_buffer_read_finish(iter->buffer_iter[cpu]); | |
3013 | } | |
3014 | ||
bc0c38d1 SR |
3015 | if (iter->trace && iter->trace->close) |
3016 | iter->trace->close(iter); | |
3017 | ||
debdd57f HT |
3018 | if (!iter->snapshot) |
3019 | /* reenable tracing if it was previously enabled */ | |
2b6080f2 | 3020 | tracing_start_tr(tr); |
e45ccd09 AL |
3021 | |
3022 | __trace_array_put(tr); | |
3023 | ||
bc0c38d1 SR |
3024 | mutex_unlock(&trace_types_lock); |
3025 | ||
d7350c3f | 3026 | mutex_destroy(&iter->mutex); |
b0dfa978 | 3027 | free_cpumask_var(iter->started); |
d7350c3f | 3028 | kfree(iter->trace); |
6d158a81 | 3029 | kfree(iter->buffer_iter); |
50e18b94 | 3030 | seq_release_private(inode, file); |
59d8f488 | 3031 | |
bc0c38d1 SR |
3032 | return 0; |
3033 | } | |
3034 | ||
6492334c SRRH |
3035 | static int tracing_release_generic_tr(struct inode *inode, struct file *file) |
3036 | { | |
3037 | struct trace_array *tr = inode->i_private; | |
3038 | ||
3039 | trace_array_put(tr); | |
3040 | return 0; | |
3041 | } | |
3042 | ||
6492334c SRRH |
3043 | static int tracing_single_release_tr(struct inode *inode, struct file *file) |
3044 | { | |
3045 | struct trace_array *tr = inode->i_private; | |
3046 | ||
3047 | trace_array_put(tr); | |
3048 | ||
3049 | return single_release(inode, file); | |
3050 | } | |
3051 | ||
bc0c38d1 SR |
3052 | static int tracing_open(struct inode *inode, struct file *file) |
3053 | { | |
7272711a | 3054 | struct trace_array *tr = inode->i_private; |
85a2f9b4 SR |
3055 | struct trace_iterator *iter; |
3056 | int ret = 0; | |
bc0c38d1 | 3057 | |
59d8f488 SRRH |
3058 | if (trace_array_get(tr) < 0) |
3059 | return -ENODEV; | |
3060 | ||
4acd4d00 | 3061 | /* If this file was open for write, then erase contents */ |
7272711a ON |
3062 | if ((file->f_mode & FMODE_WRITE) && (file->f_flags & O_TRUNC)) { |
3063 | int cpu = tracing_get_cpu(inode); | |
3064 | ||
3065 | if (cpu == RING_BUFFER_ALL_CPUS) | |
12883efb | 3066 | tracing_reset_online_cpus(&tr->trace_buffer); |
4acd4d00 | 3067 | else |
7272711a | 3068 | tracing_reset(&tr->trace_buffer, cpu); |
4acd4d00 | 3069 | } |
bc0c38d1 | 3070 | |
4acd4d00 | 3071 | if (file->f_mode & FMODE_READ) { |
7272711a | 3072 | iter = __tracing_open(inode, file, false); |
4acd4d00 SR |
3073 | if (IS_ERR(iter)) |
3074 | ret = PTR_ERR(iter); | |
3075 | else if (trace_flags & TRACE_ITER_LATENCY_FMT) | |
3076 | iter->iter_flags |= TRACE_FILE_LAT_FMT; | |
3077 | } | |
59d8f488 SRRH |
3078 | |
3079 | if (ret < 0) | |
3080 | trace_array_put(tr); | |
3081 | ||
bc0c38d1 SR |
3082 | return ret; |
3083 | } | |
3084 | ||
e309b41d | 3085 | static void * |
bc0c38d1 SR |
3086 | t_next(struct seq_file *m, void *v, loff_t *pos) |
3087 | { | |
f129e965 | 3088 | struct tracer *t = v; |
bc0c38d1 SR |
3089 | |
3090 | (*pos)++; | |
3091 | ||
3092 | if (t) | |
3093 | t = t->next; | |
3094 | ||
bc0c38d1 SR |
3095 | return t; |
3096 | } | |
3097 | ||
3098 | static void *t_start(struct seq_file *m, loff_t *pos) | |
3099 | { | |
f129e965 | 3100 | struct tracer *t; |
bc0c38d1 SR |
3101 | loff_t l = 0; |
3102 | ||
3103 | mutex_lock(&trace_types_lock); | |
f129e965 | 3104 | for (t = trace_types; t && l < *pos; t = t_next(m, t, &l)) |
bc0c38d1 SR |
3105 | ; |
3106 | ||
3107 | return t; | |
3108 | } | |
3109 | ||
3110 | static void t_stop(struct seq_file *m, void *p) | |
3111 | { | |
3112 | mutex_unlock(&trace_types_lock); | |
3113 | } | |
3114 | ||
3115 | static int t_show(struct seq_file *m, void *v) | |
3116 | { | |
3117 | struct tracer *t = v; | |
3118 | ||
3119 | if (!t) | |
3120 | return 0; | |
3121 | ||
3122 | seq_printf(m, "%s", t->name); | |
3123 | if (t->next) | |
3124 | seq_putc(m, ' '); | |
3125 | else | |
3126 | seq_putc(m, '\n'); | |
3127 | ||
3128 | return 0; | |
3129 | } | |
3130 | ||
88e9d34c | 3131 | static const struct seq_operations show_traces_seq_ops = { |
4bf39a94 IM |
3132 | .start = t_start, |
3133 | .next = t_next, | |
3134 | .stop = t_stop, | |
3135 | .show = t_show, | |
bc0c38d1 SR |
3136 | }; |
3137 | ||
3138 | static int show_traces_open(struct inode *inode, struct file *file) | |
3139 | { | |
60a11774 SR |
3140 | if (tracing_disabled) |
3141 | return -ENODEV; | |
3142 | ||
f129e965 | 3143 | return seq_open(file, &show_traces_seq_ops); |
bc0c38d1 SR |
3144 | } |
3145 | ||
4acd4d00 SR |
3146 | static ssize_t |
3147 | tracing_write_stub(struct file *filp, const char __user *ubuf, | |
3148 | size_t count, loff_t *ppos) | |
3149 | { | |
3150 | return count; | |
3151 | } | |
3152 | ||
364829b1 SP |
3153 | static loff_t tracing_seek(struct file *file, loff_t offset, int origin) |
3154 | { | |
3155 | if (file->f_mode & FMODE_READ) | |
3156 | return seq_lseek(file, offset, origin); | |
3157 | else | |
3158 | return 0; | |
3159 | } | |
3160 | ||
5e2336a0 | 3161 | static const struct file_operations tracing_fops = { |
4bf39a94 IM |
3162 | .open = tracing_open, |
3163 | .read = seq_read, | |
4acd4d00 | 3164 | .write = tracing_write_stub, |
364829b1 | 3165 | .llseek = tracing_seek, |
4bf39a94 | 3166 | .release = tracing_release, |
bc0c38d1 SR |
3167 | }; |
3168 | ||
5e2336a0 | 3169 | static const struct file_operations show_traces_fops = { |
c7078de1 IM |
3170 | .open = show_traces_open, |
3171 | .read = seq_read, | |
3172 | .release = seq_release, | |
b444786f | 3173 | .llseek = seq_lseek, |
c7078de1 IM |
3174 | }; |
3175 | ||
36dfe925 IM |
3176 | /* |
3177 | * Only trace on a CPU if the bitmask is set: | |
3178 | */ | |
9e01c1b7 | 3179 | static cpumask_var_t tracing_cpumask; |
36dfe925 IM |
3180 | |
3181 | /* | |
3182 | * The tracer itself will not take this lock, but still we want | |
3183 | * to provide a consistent cpumask to user-space: | |
3184 | */ | |
3185 | static DEFINE_MUTEX(tracing_cpumask_update_lock); | |
3186 | ||
3187 | /* | |
3188 | * Temporary storage for the character representation of the | |
3189 | * CPU bitmask (and one more byte for the newline): | |
3190 | */ | |
3191 | static char mask_str[NR_CPUS + 1]; | |
3192 | ||
c7078de1 IM |
3193 | static ssize_t |
3194 | tracing_cpumask_read(struct file *filp, char __user *ubuf, | |
3195 | size_t count, loff_t *ppos) | |
3196 | { | |
36dfe925 | 3197 | int len; |
c7078de1 IM |
3198 | |
3199 | mutex_lock(&tracing_cpumask_update_lock); | |
36dfe925 | 3200 | |
9e01c1b7 | 3201 | len = cpumask_scnprintf(mask_str, count, tracing_cpumask); |
36dfe925 IM |
3202 | if (count - len < 2) { |
3203 | count = -EINVAL; | |
3204 | goto out_err; | |
3205 | } | |
3206 | len += sprintf(mask_str + len, "\n"); | |
3207 | count = simple_read_from_buffer(ubuf, count, ppos, mask_str, NR_CPUS+1); | |
3208 | ||
3209 | out_err: | |
c7078de1 IM |
3210 | mutex_unlock(&tracing_cpumask_update_lock); |
3211 | ||
3212 | return count; | |
3213 | } | |
3214 | ||
3215 | static ssize_t | |
3216 | tracing_cpumask_write(struct file *filp, const char __user *ubuf, | |
3217 | size_t count, loff_t *ppos) | |
3218 | { | |
2b6080f2 | 3219 | struct trace_array *tr = filp->private_data; |
9e01c1b7 | 3220 | cpumask_var_t tracing_cpumask_new; |
2b6080f2 | 3221 | int err, cpu; |
9e01c1b7 RR |
3222 | |
3223 | if (!alloc_cpumask_var(&tracing_cpumask_new, GFP_KERNEL)) | |
3224 | return -ENOMEM; | |
c7078de1 | 3225 | |
9e01c1b7 | 3226 | err = cpumask_parse_user(ubuf, count, tracing_cpumask_new); |
c7078de1 | 3227 | if (err) |
36dfe925 IM |
3228 | goto err_unlock; |
3229 | ||
215368e8 LZ |
3230 | mutex_lock(&tracing_cpumask_update_lock); |
3231 | ||
a5e25883 | 3232 | local_irq_disable(); |
0199c4e6 | 3233 | arch_spin_lock(&ftrace_max_lock); |
ab46428c | 3234 | for_each_tracing_cpu(cpu) { |
36dfe925 IM |
3235 | /* |
3236 | * Increase/decrease the disabled counter if we are | |
3237 | * about to flip a bit in the cpumask: | |
3238 | */ | |
9e01c1b7 RR |
3239 | if (cpumask_test_cpu(cpu, tracing_cpumask) && |
3240 | !cpumask_test_cpu(cpu, tracing_cpumask_new)) { | |
12883efb SRRH |
3241 | atomic_inc(&per_cpu_ptr(tr->trace_buffer.data, cpu)->disabled); |
3242 | ring_buffer_record_disable_cpu(tr->trace_buffer.buffer, cpu); | |
36dfe925 | 3243 | } |
9e01c1b7 RR |
3244 | if (!cpumask_test_cpu(cpu, tracing_cpumask) && |
3245 | cpumask_test_cpu(cpu, tracing_cpumask_new)) { | |
12883efb SRRH |
3246 | atomic_dec(&per_cpu_ptr(tr->trace_buffer.data, cpu)->disabled); |
3247 | ring_buffer_record_enable_cpu(tr->trace_buffer.buffer, cpu); | |
36dfe925 IM |
3248 | } |
3249 | } | |
0199c4e6 | 3250 | arch_spin_unlock(&ftrace_max_lock); |
a5e25883 | 3251 | local_irq_enable(); |
36dfe925 | 3252 | |
9e01c1b7 | 3253 | cpumask_copy(tracing_cpumask, tracing_cpumask_new); |
36dfe925 IM |
3254 | |
3255 | mutex_unlock(&tracing_cpumask_update_lock); | |
9e01c1b7 | 3256 | free_cpumask_var(tracing_cpumask_new); |
c7078de1 IM |
3257 | |
3258 | return count; | |
36dfe925 IM |
3259 | |
3260 | err_unlock: | |
215368e8 | 3261 | free_cpumask_var(tracing_cpumask_new); |
36dfe925 IM |
3262 | |
3263 | return err; | |
c7078de1 IM |
3264 | } |
3265 | ||
5e2336a0 | 3266 | static const struct file_operations tracing_cpumask_fops = { |
c7078de1 IM |
3267 | .open = tracing_open_generic, |
3268 | .read = tracing_cpumask_read, | |
3269 | .write = tracing_cpumask_write, | |
b444786f | 3270 | .llseek = generic_file_llseek, |
bc0c38d1 SR |
3271 | }; |
3272 | ||
fdb372ed | 3273 | static int tracing_trace_options_show(struct seq_file *m, void *v) |
bc0c38d1 | 3274 | { |
d8e83d26 | 3275 | struct tracer_opt *trace_opts; |
2b6080f2 | 3276 | struct trace_array *tr = m->private; |
d8e83d26 | 3277 | u32 tracer_flags; |
d8e83d26 | 3278 | int i; |
adf9f195 | 3279 | |
d8e83d26 | 3280 | mutex_lock(&trace_types_lock); |
2b6080f2 SR |
3281 | tracer_flags = tr->current_trace->flags->val; |
3282 | trace_opts = tr->current_trace->flags->opts; | |
d8e83d26 | 3283 | |
bc0c38d1 SR |
3284 | for (i = 0; trace_options[i]; i++) { |
3285 | if (trace_flags & (1 << i)) | |
fdb372ed | 3286 | seq_printf(m, "%s\n", trace_options[i]); |
bc0c38d1 | 3287 | else |
fdb372ed | 3288 | seq_printf(m, "no%s\n", trace_options[i]); |
bc0c38d1 SR |
3289 | } |
3290 | ||
adf9f195 FW |
3291 | for (i = 0; trace_opts[i].name; i++) { |
3292 | if (tracer_flags & trace_opts[i].bit) | |
fdb372ed | 3293 | seq_printf(m, "%s\n", trace_opts[i].name); |
adf9f195 | 3294 | else |
fdb372ed | 3295 | seq_printf(m, "no%s\n", trace_opts[i].name); |
adf9f195 | 3296 | } |
d8e83d26 | 3297 | mutex_unlock(&trace_types_lock); |
adf9f195 | 3298 | |
fdb372ed | 3299 | return 0; |
bc0c38d1 | 3300 | } |
bc0c38d1 | 3301 | |
8d18eaaf LZ |
3302 | static int __set_tracer_option(struct tracer *trace, |
3303 | struct tracer_flags *tracer_flags, | |
3304 | struct tracer_opt *opts, int neg) | |
3305 | { | |
3306 | int ret; | |
bc0c38d1 | 3307 | |
8d18eaaf LZ |
3308 | ret = trace->set_flag(tracer_flags->val, opts->bit, !neg); |
3309 | if (ret) | |
3310 | return ret; | |
3311 | ||
3312 | if (neg) | |
3313 | tracer_flags->val &= ~opts->bit; | |
3314 | else | |
3315 | tracer_flags->val |= opts->bit; | |
3316 | return 0; | |
bc0c38d1 SR |
3317 | } |
3318 | ||
adf9f195 FW |
3319 | /* Try to assign a tracer specific option */ |
3320 | static int set_tracer_option(struct tracer *trace, char *cmp, int neg) | |
3321 | { | |
7770841e | 3322 | struct tracer_flags *tracer_flags = trace->flags; |
adf9f195 | 3323 | struct tracer_opt *opts = NULL; |
8d18eaaf | 3324 | int i; |
adf9f195 | 3325 | |
7770841e Z |
3326 | for (i = 0; tracer_flags->opts[i].name; i++) { |
3327 | opts = &tracer_flags->opts[i]; | |
adf9f195 | 3328 | |
8d18eaaf LZ |
3329 | if (strcmp(cmp, opts->name) == 0) |
3330 | return __set_tracer_option(trace, trace->flags, | |
3331 | opts, neg); | |
adf9f195 | 3332 | } |
adf9f195 | 3333 | |
8d18eaaf | 3334 | return -EINVAL; |
adf9f195 FW |
3335 | } |
3336 | ||
613f04a0 SRRH |
3337 | /* Some tracers require overwrite to stay enabled */ |
3338 | int trace_keep_overwrite(struct tracer *tracer, u32 mask, int set) | |
3339 | { | |
3340 | if (tracer->enabled && (mask & TRACE_ITER_OVERWRITE) && !set) | |
3341 | return -1; | |
3342 | ||
3343 | return 0; | |
3344 | } | |
3345 | ||
2b6080f2 | 3346 | int set_tracer_flag(struct trace_array *tr, unsigned int mask, int enabled) |
af4617bd SR |
3347 | { |
3348 | /* do nothing if flag is already set */ | |
3349 | if (!!(trace_flags & mask) == !!enabled) | |
613f04a0 SRRH |
3350 | return 0; |
3351 | ||
3352 | /* Give the tracer a chance to approve the change */ | |
2b6080f2 SR |
3353 | if (tr->current_trace->flag_changed) |
3354 | if (tr->current_trace->flag_changed(tr->current_trace, mask, !!enabled)) | |
613f04a0 | 3355 | return -EINVAL; |
af4617bd SR |
3356 | |
3357 | if (enabled) | |
3358 | trace_flags |= mask; | |
3359 | else | |
3360 | trace_flags &= ~mask; | |
e870e9a1 LZ |
3361 | |
3362 | if (mask == TRACE_ITER_RECORD_CMD) | |
3363 | trace_event_enable_cmd_record(enabled); | |
750912fa | 3364 | |
80902822 | 3365 | if (mask == TRACE_ITER_OVERWRITE) { |
12883efb | 3366 | ring_buffer_change_overwrite(tr->trace_buffer.buffer, enabled); |
80902822 | 3367 | #ifdef CONFIG_TRACER_MAX_TRACE |
12883efb | 3368 | ring_buffer_change_overwrite(tr->max_buffer.buffer, enabled); |
80902822 SRRH |
3369 | #endif |
3370 | } | |
81698831 SR |
3371 | |
3372 | if (mask == TRACE_ITER_PRINTK) | |
3373 | trace_printk_start_stop_comm(enabled); | |
613f04a0 SRRH |
3374 | |
3375 | return 0; | |
af4617bd SR |
3376 | } |
3377 | ||
2b6080f2 | 3378 | static int trace_set_options(struct trace_array *tr, char *option) |
bc0c38d1 | 3379 | { |
8d18eaaf | 3380 | char *cmp; |
bc0c38d1 | 3381 | int neg = 0; |
613f04a0 | 3382 | int ret = -ENODEV; |
bc0c38d1 SR |
3383 | int i; |
3384 | ||
7bcfaf54 | 3385 | cmp = strstrip(option); |
bc0c38d1 | 3386 | |
8d18eaaf | 3387 | if (strncmp(cmp, "no", 2) == 0) { |
bc0c38d1 SR |
3388 | neg = 1; |
3389 | cmp += 2; | |
3390 | } | |
3391 | ||
69d34da2 SRRH |
3392 | mutex_lock(&trace_types_lock); |
3393 | ||
bc0c38d1 | 3394 | for (i = 0; trace_options[i]; i++) { |
8d18eaaf | 3395 | if (strcmp(cmp, trace_options[i]) == 0) { |
2b6080f2 | 3396 | ret = set_tracer_flag(tr, 1 << i, !neg); |
bc0c38d1 SR |
3397 | break; |
3398 | } | |
3399 | } | |
adf9f195 FW |
3400 | |
3401 | /* If no option could be set, test the specific tracer options */ | |
69d34da2 | 3402 | if (!trace_options[i]) |
2b6080f2 | 3403 | ret = set_tracer_option(tr->current_trace, cmp, neg); |
69d34da2 SRRH |
3404 | |
3405 | mutex_unlock(&trace_types_lock); | |
bc0c38d1 | 3406 | |
7bcfaf54 SR |
3407 | return ret; |
3408 | } | |
3409 | ||
3410 | static ssize_t | |
3411 | tracing_trace_options_write(struct file *filp, const char __user *ubuf, | |
3412 | size_t cnt, loff_t *ppos) | |
3413 | { | |
2b6080f2 SR |
3414 | struct seq_file *m = filp->private_data; |
3415 | struct trace_array *tr = m->private; | |
7bcfaf54 | 3416 | char buf[64]; |
613f04a0 | 3417 | int ret; |
7bcfaf54 SR |
3418 | |
3419 | if (cnt >= sizeof(buf)) | |
3420 | return -EINVAL; | |
3421 | ||
3422 | if (copy_from_user(&buf, ubuf, cnt)) | |
3423 | return -EFAULT; | |
3424 | ||
a8dd2176 SR |
3425 | buf[cnt] = 0; |
3426 | ||
2b6080f2 | 3427 | ret = trace_set_options(tr, buf); |
613f04a0 SRRH |
3428 | if (ret < 0) |
3429 | return ret; | |
7bcfaf54 | 3430 | |
cf8517cf | 3431 | *ppos += cnt; |
bc0c38d1 SR |
3432 | |
3433 | return cnt; | |
3434 | } | |
3435 | ||
fdb372ed LZ |
3436 | static int tracing_trace_options_open(struct inode *inode, struct file *file) |
3437 | { | |
6492334c | 3438 | struct trace_array *tr = inode->i_private; |
e45ccd09 | 3439 | int ret; |
6492334c | 3440 | |
fdb372ed LZ |
3441 | if (tracing_disabled) |
3442 | return -ENODEV; | |
2b6080f2 | 3443 | |
6492334c SRRH |
3444 | if (trace_array_get(tr) < 0) |
3445 | return -ENODEV; | |
3446 | ||
e45ccd09 AL |
3447 | ret = single_open(file, tracing_trace_options_show, inode->i_private); |
3448 | if (ret < 0) | |
3449 | trace_array_put(tr); | |
3450 | ||
3451 | return ret; | |
fdb372ed LZ |
3452 | } |
3453 | ||
5e2336a0 | 3454 | static const struct file_operations tracing_iter_fops = { |
fdb372ed LZ |
3455 | .open = tracing_trace_options_open, |
3456 | .read = seq_read, | |
3457 | .llseek = seq_lseek, | |
6492334c | 3458 | .release = tracing_single_release_tr, |
ee6bce52 | 3459 | .write = tracing_trace_options_write, |
bc0c38d1 SR |
3460 | }; |
3461 | ||
7bd2f24c IM |
3462 | static const char readme_msg[] = |
3463 | "tracing mini-HOWTO:\n\n" | |
22f45649 SRRH |
3464 | "# echo 0 > tracing_on : quick way to disable tracing\n" |
3465 | "# echo 1 > tracing_on : quick way to re-enable tracing\n\n" | |
3466 | " Important files:\n" | |
3467 | " trace\t\t\t- The static contents of the buffer\n" | |
3468 | "\t\t\t To clear the buffer write into this file: echo > trace\n" | |
3469 | " trace_pipe\t\t- A consuming read to see the contents of the buffer\n" | |
3470 | " current_tracer\t- function and latency tracers\n" | |
3471 | " available_tracers\t- list of configured tracers for current_tracer\n" | |
3472 | " buffer_size_kb\t- view and modify size of per cpu buffer\n" | |
3473 | " buffer_total_size_kb - view total size of all cpu buffers\n\n" | |
3474 | " trace_clock\t\t-change the clock used to order events\n" | |
3475 | " local: Per cpu clock but may not be synced across CPUs\n" | |
3476 | " global: Synced across CPUs but slows tracing down.\n" | |
3477 | " counter: Not a clock, but just an increment\n" | |
3478 | " uptime: Jiffy counter from time of boot\n" | |
3479 | " perf: Same clock that perf events use\n" | |
3480 | #ifdef CONFIG_X86_64 | |
3481 | " x86-tsc: TSC cycle counter\n" | |
3482 | #endif | |
3483 | "\n trace_marker\t\t- Writes into this file writes into the kernel buffer\n" | |
3484 | " tracing_cpumask\t- Limit which CPUs to trace\n" | |
3485 | " instances\t\t- Make sub-buffers with: mkdir instances/foo\n" | |
3486 | "\t\t\t Remove sub-buffer with rmdir\n" | |
3487 | " trace_options\t\t- Set format or modify how tracing happens\n" | |
3488 | "\t\t\t Disable an option by adding a suffix 'no' to the option name\n" | |
3489 | #ifdef CONFIG_DYNAMIC_FTRACE | |
3490 | "\n available_filter_functions - list of functions that can be filtered on\n" | |
3491 | " set_ftrace_filter\t- echo function name in here to only trace these functions\n" | |
3492 | " accepts: func_full_name, *func_end, func_begin*, *func_middle*\n" | |
3493 | " modules: Can select a group via module\n" | |
3494 | " Format: :mod:<module-name>\n" | |
3495 | " example: echo :mod:ext3 > set_ftrace_filter\n" | |
3496 | " triggers: a command to perform when function is hit\n" | |
3497 | " Format: <function>:<trigger>[:count]\n" | |
3498 | " trigger: traceon, traceoff\n" | |
3499 | " enable_event:<system>:<event>\n" | |
3500 | " disable_event:<system>:<event>\n" | |
3501 | #ifdef CONFIG_STACKTRACE | |
3502 | " stacktrace\n" | |
3503 | #endif | |
3504 | #ifdef CONFIG_TRACER_SNAPSHOT | |
3505 | " snapshot\n" | |
3506 | #endif | |
3507 | " example: echo do_fault:traceoff > set_ftrace_filter\n" | |
3508 | " echo do_trap:traceoff:3 > set_ftrace_filter\n" | |
3509 | " The first one will disable tracing every time do_fault is hit\n" | |
3510 | " The second will disable tracing at most 3 times when do_trap is hit\n" | |
3511 | " The first time do trap is hit and it disables tracing, the counter\n" | |
3512 | " will decrement to 2. If tracing is already disabled, the counter\n" | |
3513 | " will not decrement. It only decrements when the trigger did work\n" | |
3514 | " To remove trigger without count:\n" | |
3515 | " echo '!<function>:<trigger> > set_ftrace_filter\n" | |
3516 | " To remove trigger with a count:\n" | |
3517 | " echo '!<function>:<trigger>:0 > set_ftrace_filter\n" | |
3518 | " set_ftrace_notrace\t- echo function name in here to never trace.\n" | |
3519 | " accepts: func_full_name, *func_end, func_begin*, *func_middle*\n" | |
3520 | " modules: Can select a group via module command :mod:\n" | |
3521 | " Does not accept triggers\n" | |
3522 | #endif /* CONFIG_DYNAMIC_FTRACE */ | |
3523 | #ifdef CONFIG_FUNCTION_TRACER | |
3524 | " set_ftrace_pid\t- Write pid(s) to only function trace those pids (function)\n" | |
3525 | #endif | |
3526 | #ifdef CONFIG_FUNCTION_GRAPH_TRACER | |
3527 | " set_graph_function\t- Trace the nested calls of a function (function_graph)\n" | |
3528 | " max_graph_depth\t- Trace a limited depth of nested calls (0 is unlimited)\n" | |
3529 | #endif | |
3530 | #ifdef CONFIG_TRACER_SNAPSHOT | |
3531 | "\n snapshot\t\t- Like 'trace' but shows the content of the static snapshot buffer\n" | |
3532 | "\t\t\t Read the contents for more information\n" | |
3533 | #endif | |
3534 | #ifdef CONFIG_STACKTRACE | |
3535 | " stack_trace\t\t- Shows the max stack trace when active\n" | |
3536 | " stack_max_size\t- Shows current max stack size that was traced\n" | |
3537 | "\t\t\t Write into this file to reset the max size (trigger a new trace)\n" | |
3538 | #ifdef CONFIG_DYNAMIC_FTRACE | |
3539 | " stack_trace_filter\t- Like set_ftrace_filter but limits what stack_trace traces\n" | |
3540 | #endif | |
3541 | #endif /* CONFIG_STACKTRACE */ | |
7bd2f24c IM |
3542 | ; |
3543 | ||
3544 | static ssize_t | |
3545 | tracing_readme_read(struct file *filp, char __user *ubuf, | |
3546 | size_t cnt, loff_t *ppos) | |
3547 | { | |
3548 | return simple_read_from_buffer(ubuf, cnt, ppos, | |
3549 | readme_msg, strlen(readme_msg)); | |
3550 | } | |
3551 | ||
5e2336a0 | 3552 | static const struct file_operations tracing_readme_fops = { |
c7078de1 IM |
3553 | .open = tracing_open_generic, |
3554 | .read = tracing_readme_read, | |
b444786f | 3555 | .llseek = generic_file_llseek, |
7bd2f24c IM |
3556 | }; |
3557 | ||
69abe6a5 AP |
3558 | static ssize_t |
3559 | tracing_saved_cmdlines_read(struct file *file, char __user *ubuf, | |
3560 | size_t cnt, loff_t *ppos) | |
3561 | { | |
3562 | char *buf_comm; | |
3563 | char *file_buf; | |
3564 | char *buf; | |
3565 | int len = 0; | |
3566 | int pid; | |
3567 | int i; | |
3568 | ||
3569 | file_buf = kmalloc(SAVED_CMDLINES*(16+TASK_COMM_LEN), GFP_KERNEL); | |
3570 | if (!file_buf) | |
3571 | return -ENOMEM; | |
3572 | ||
3573 | buf_comm = kmalloc(TASK_COMM_LEN, GFP_KERNEL); | |
3574 | if (!buf_comm) { | |
3575 | kfree(file_buf); | |
3576 | return -ENOMEM; | |
3577 | } | |
3578 | ||
3579 | buf = file_buf; | |
3580 | ||
3581 | for (i = 0; i < SAVED_CMDLINES; i++) { | |
3582 | int r; | |
3583 | ||
3584 | pid = map_cmdline_to_pid[i]; | |
3585 | if (pid == -1 || pid == NO_CMDLINE_MAP) | |
3586 | continue; | |
3587 | ||
3588 | trace_find_cmdline(pid, buf_comm); | |
3589 | r = sprintf(buf, "%d %s\n", pid, buf_comm); | |
3590 | buf += r; | |
3591 | len += r; | |
3592 | } | |
3593 | ||
3594 | len = simple_read_from_buffer(ubuf, cnt, ppos, | |
3595 | file_buf, len); | |
3596 | ||
3597 | kfree(file_buf); | |
3598 | kfree(buf_comm); | |
3599 | ||
3600 | return len; | |
3601 | } | |
3602 | ||
3603 | static const struct file_operations tracing_saved_cmdlines_fops = { | |
3604 | .open = tracing_open_generic, | |
3605 | .read = tracing_saved_cmdlines_read, | |
b444786f | 3606 | .llseek = generic_file_llseek, |
69abe6a5 AP |
3607 | }; |
3608 | ||
bc0c38d1 SR |
3609 | static ssize_t |
3610 | tracing_set_trace_read(struct file *filp, char __user *ubuf, | |
3611 | size_t cnt, loff_t *ppos) | |
3612 | { | |
2b6080f2 | 3613 | struct trace_array *tr = filp->private_data; |
ee6c2c1b | 3614 | char buf[MAX_TRACER_SIZE+2]; |
bc0c38d1 SR |
3615 | int r; |
3616 | ||
3617 | mutex_lock(&trace_types_lock); | |
2b6080f2 | 3618 | r = sprintf(buf, "%s\n", tr->current_trace->name); |
bc0c38d1 SR |
3619 | mutex_unlock(&trace_types_lock); |
3620 | ||
4bf39a94 | 3621 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, r); |
bc0c38d1 SR |
3622 | } |
3623 | ||
b6f11df2 ACM |
3624 | int tracer_init(struct tracer *t, struct trace_array *tr) |
3625 | { | |
12883efb | 3626 | tracing_reset_online_cpus(&tr->trace_buffer); |
b6f11df2 ACM |
3627 | return t->init(tr); |
3628 | } | |
3629 | ||
12883efb | 3630 | static void set_buffer_entries(struct trace_buffer *buf, unsigned long val) |
438ced17 VN |
3631 | { |
3632 | int cpu; | |
737223fb | 3633 | |
438ced17 | 3634 | for_each_tracing_cpu(cpu) |
12883efb | 3635 | per_cpu_ptr(buf->data, cpu)->entries = val; |
438ced17 VN |
3636 | } |
3637 | ||
12883efb | 3638 | #ifdef CONFIG_TRACER_MAX_TRACE |
d60da506 | 3639 | /* resize @tr's buffer to the size of @size_tr's entries */ |
12883efb SRRH |
3640 | static int resize_buffer_duplicate_size(struct trace_buffer *trace_buf, |
3641 | struct trace_buffer *size_buf, int cpu_id) | |
d60da506 HT |
3642 | { |
3643 | int cpu, ret = 0; | |
3644 | ||
3645 | if (cpu_id == RING_BUFFER_ALL_CPUS) { | |
3646 | for_each_tracing_cpu(cpu) { | |
12883efb SRRH |
3647 | ret = ring_buffer_resize(trace_buf->buffer, |
3648 | per_cpu_ptr(size_buf->data, cpu)->entries, cpu); | |
d60da506 HT |
3649 | if (ret < 0) |
3650 | break; | |
12883efb SRRH |
3651 | per_cpu_ptr(trace_buf->data, cpu)->entries = |
3652 | per_cpu_ptr(size_buf->data, cpu)->entries; | |
d60da506 HT |
3653 | } |
3654 | } else { | |
12883efb SRRH |
3655 | ret = ring_buffer_resize(trace_buf->buffer, |
3656 | per_cpu_ptr(size_buf->data, cpu_id)->entries, cpu_id); | |
d60da506 | 3657 | if (ret == 0) |
12883efb SRRH |
3658 | per_cpu_ptr(trace_buf->data, cpu_id)->entries = |
3659 | per_cpu_ptr(size_buf->data, cpu_id)->entries; | |
d60da506 HT |
3660 | } |
3661 | ||
3662 | return ret; | |
3663 | } | |
12883efb | 3664 | #endif /* CONFIG_TRACER_MAX_TRACE */ |
d60da506 | 3665 | |
2b6080f2 SR |
3666 | static int __tracing_resize_ring_buffer(struct trace_array *tr, |
3667 | unsigned long size, int cpu) | |
73c5162a SR |
3668 | { |
3669 | int ret; | |
3670 | ||
3671 | /* | |
3672 | * If kernel or user changes the size of the ring buffer | |
a123c52b SR |
3673 | * we use the size that was given, and we can forget about |
3674 | * expanding it later. | |
73c5162a | 3675 | */ |
55034cd6 | 3676 | ring_buffer_expanded = true; |
73c5162a | 3677 | |
b382ede6 | 3678 | /* May be called before buffers are initialized */ |
12883efb | 3679 | if (!tr->trace_buffer.buffer) |
b382ede6 SR |
3680 | return 0; |
3681 | ||
12883efb | 3682 | ret = ring_buffer_resize(tr->trace_buffer.buffer, size, cpu); |
73c5162a SR |
3683 | if (ret < 0) |
3684 | return ret; | |
3685 | ||
12883efb | 3686 | #ifdef CONFIG_TRACER_MAX_TRACE |
2b6080f2 SR |
3687 | if (!(tr->flags & TRACE_ARRAY_FL_GLOBAL) || |
3688 | !tr->current_trace->use_max_tr) | |
ef710e10 KM |
3689 | goto out; |
3690 | ||
12883efb | 3691 | ret = ring_buffer_resize(tr->max_buffer.buffer, size, cpu); |
73c5162a | 3692 | if (ret < 0) { |
12883efb SRRH |
3693 | int r = resize_buffer_duplicate_size(&tr->trace_buffer, |
3694 | &tr->trace_buffer, cpu); | |
73c5162a | 3695 | if (r < 0) { |
a123c52b SR |
3696 | /* |
3697 | * AARGH! We are left with different | |
3698 | * size max buffer!!!! | |
3699 | * The max buffer is our "snapshot" buffer. | |
3700 | * When a tracer needs a snapshot (one of the | |
3701 | * latency tracers), it swaps the max buffer | |
3702 | * with the saved snap shot. We succeeded to | |
3703 | * update the size of the main buffer, but failed to | |
3704 | * update the size of the max buffer. But when we tried | |
3705 | * to reset the main buffer to the original size, we | |
3706 | * failed there too. This is very unlikely to | |
3707 | * happen, but if it does, warn and kill all | |
3708 | * tracing. | |
3709 | */ | |
73c5162a SR |
3710 | WARN_ON(1); |
3711 | tracing_disabled = 1; | |
3712 | } | |
3713 | return ret; | |
3714 | } | |
3715 | ||
438ced17 | 3716 | if (cpu == RING_BUFFER_ALL_CPUS) |
12883efb | 3717 | set_buffer_entries(&tr->max_buffer, size); |
438ced17 | 3718 | else |
12883efb | 3719 | per_cpu_ptr(tr->max_buffer.data, cpu)->entries = size; |
438ced17 | 3720 | |
ef710e10 | 3721 | out: |
12883efb SRRH |
3722 | #endif /* CONFIG_TRACER_MAX_TRACE */ |
3723 | ||
438ced17 | 3724 | if (cpu == RING_BUFFER_ALL_CPUS) |
12883efb | 3725 | set_buffer_entries(&tr->trace_buffer, size); |
438ced17 | 3726 | else |
12883efb | 3727 | per_cpu_ptr(tr->trace_buffer.data, cpu)->entries = size; |
73c5162a SR |
3728 | |
3729 | return ret; | |
3730 | } | |
3731 | ||
2b6080f2 SR |
3732 | static ssize_t tracing_resize_ring_buffer(struct trace_array *tr, |
3733 | unsigned long size, int cpu_id) | |
4f271a2a | 3734 | { |
83f40318 | 3735 | int ret = size; |
4f271a2a VN |
3736 | |
3737 | mutex_lock(&trace_types_lock); | |
3738 | ||
438ced17 VN |
3739 | if (cpu_id != RING_BUFFER_ALL_CPUS) { |
3740 | /* make sure, this cpu is enabled in the mask */ | |
3741 | if (!cpumask_test_cpu(cpu_id, tracing_buffer_mask)) { | |
3742 | ret = -EINVAL; | |
3743 | goto out; | |
3744 | } | |
3745 | } | |
4f271a2a | 3746 | |
2b6080f2 | 3747 | ret = __tracing_resize_ring_buffer(tr, size, cpu_id); |
4f271a2a VN |
3748 | if (ret < 0) |
3749 | ret = -ENOMEM; | |
3750 | ||
438ced17 | 3751 | out: |
4f271a2a VN |
3752 | mutex_unlock(&trace_types_lock); |
3753 | ||
3754 | return ret; | |
3755 | } | |
3756 | ||
ef710e10 | 3757 | |
1852fcce SR |
3758 | /** |
3759 | * tracing_update_buffers - used by tracing facility to expand ring buffers | |
3760 | * | |
3761 | * To save on memory when the tracing is never used on a system with it | |
3762 | * configured in. The ring buffers are set to a minimum size. But once | |
3763 | * a user starts to use the tracing facility, then they need to grow | |
3764 | * to their default size. | |
3765 | * | |
3766 | * This function is to be called when a tracer is about to be used. | |
3767 | */ | |
3768 | int tracing_update_buffers(void) | |
3769 | { | |
3770 | int ret = 0; | |
3771 | ||
1027fcb2 | 3772 | mutex_lock(&trace_types_lock); |
1852fcce | 3773 | if (!ring_buffer_expanded) |
2b6080f2 | 3774 | ret = __tracing_resize_ring_buffer(&global_trace, trace_buf_size, |
438ced17 | 3775 | RING_BUFFER_ALL_CPUS); |
1027fcb2 | 3776 | mutex_unlock(&trace_types_lock); |
1852fcce SR |
3777 | |
3778 | return ret; | |
3779 | } | |
3780 | ||
577b785f SR |
3781 | struct trace_option_dentry; |
3782 | ||
3783 | static struct trace_option_dentry * | |
2b6080f2 | 3784 | create_trace_option_files(struct trace_array *tr, struct tracer *tracer); |
577b785f SR |
3785 | |
3786 | static void | |
3787 | destroy_trace_option_files(struct trace_option_dentry *topts); | |
3788 | ||
b2821ae6 | 3789 | static int tracing_set_tracer(const char *buf) |
bc0c38d1 | 3790 | { |
577b785f | 3791 | static struct trace_option_dentry *topts; |
bc0c38d1 SR |
3792 | struct trace_array *tr = &global_trace; |
3793 | struct tracer *t; | |
12883efb | 3794 | #ifdef CONFIG_TRACER_MAX_TRACE |
34600f0e | 3795 | bool had_max_tr; |
12883efb | 3796 | #endif |
d9e54076 | 3797 | int ret = 0; |
bc0c38d1 | 3798 | |
1027fcb2 SR |
3799 | mutex_lock(&trace_types_lock); |
3800 | ||
73c5162a | 3801 | if (!ring_buffer_expanded) { |
2b6080f2 | 3802 | ret = __tracing_resize_ring_buffer(tr, trace_buf_size, |
438ced17 | 3803 | RING_BUFFER_ALL_CPUS); |
73c5162a | 3804 | if (ret < 0) |
59f586db | 3805 | goto out; |
73c5162a SR |
3806 | ret = 0; |
3807 | } | |
3808 | ||
bc0c38d1 SR |
3809 | for (t = trace_types; t; t = t->next) { |
3810 | if (strcmp(t->name, buf) == 0) | |
3811 | break; | |
3812 | } | |
c2931e05 FW |
3813 | if (!t) { |
3814 | ret = -EINVAL; | |
3815 | goto out; | |
3816 | } | |
2b6080f2 | 3817 | if (t == tr->current_trace) |
bc0c38d1 SR |
3818 | goto out; |
3819 | ||
9f029e83 | 3820 | trace_branch_disable(); |
613f04a0 | 3821 | |
2b6080f2 | 3822 | tr->current_trace->enabled = false; |
613f04a0 | 3823 | |
2b6080f2 SR |
3824 | if (tr->current_trace->reset) |
3825 | tr->current_trace->reset(tr); | |
34600f0e | 3826 | |
12883efb | 3827 | /* Current trace needs to be nop_trace before synchronize_sched */ |
2b6080f2 | 3828 | tr->current_trace = &nop_trace; |
34600f0e | 3829 | |
45ad21ca SRRH |
3830 | #ifdef CONFIG_TRACER_MAX_TRACE |
3831 | had_max_tr = tr->allocated_snapshot; | |
34600f0e SR |
3832 | |
3833 | if (had_max_tr && !t->use_max_tr) { | |
3834 | /* | |
3835 | * We need to make sure that the update_max_tr sees that | |
3836 | * current_trace changed to nop_trace to keep it from | |
3837 | * swapping the buffers after we resize it. | |
3838 | * The update_max_tr is called from interrupts disabled | |
3839 | * so a synchronized_sched() is sufficient. | |
3840 | */ | |
3841 | synchronize_sched(); | |
3209cff4 | 3842 | free_snapshot(tr); |
ef710e10 | 3843 | } |
12883efb | 3844 | #endif |
577b785f SR |
3845 | destroy_trace_option_files(topts); |
3846 | ||
2b6080f2 | 3847 | topts = create_trace_option_files(tr, t); |
12883efb SRRH |
3848 | |
3849 | #ifdef CONFIG_TRACER_MAX_TRACE | |
34600f0e | 3850 | if (t->use_max_tr && !had_max_tr) { |
3209cff4 | 3851 | ret = alloc_snapshot(tr); |
d60da506 HT |
3852 | if (ret < 0) |
3853 | goto out; | |
ef710e10 | 3854 | } |
12883efb | 3855 | #endif |
577b785f | 3856 | |
1c80025a | 3857 | if (t->init) { |
b6f11df2 | 3858 | ret = tracer_init(t, tr); |
1c80025a FW |
3859 | if (ret) |
3860 | goto out; | |
3861 | } | |
bc0c38d1 | 3862 | |
2b6080f2 SR |
3863 | tr->current_trace = t; |
3864 | tr->current_trace->enabled = true; | |
9f029e83 | 3865 | trace_branch_enable(tr); |
bc0c38d1 SR |
3866 | out: |
3867 | mutex_unlock(&trace_types_lock); | |
3868 | ||
d9e54076 PZ |
3869 | return ret; |
3870 | } | |
3871 | ||
3872 | static ssize_t | |
3873 | tracing_set_trace_write(struct file *filp, const char __user *ubuf, | |
3874 | size_t cnt, loff_t *ppos) | |
3875 | { | |
ee6c2c1b | 3876 | char buf[MAX_TRACER_SIZE+1]; |
d9e54076 PZ |
3877 | int i; |
3878 | size_t ret; | |
e6e7a65a FW |
3879 | int err; |
3880 | ||
3881 | ret = cnt; | |
d9e54076 | 3882 | |
ee6c2c1b LZ |
3883 | if (cnt > MAX_TRACER_SIZE) |
3884 | cnt = MAX_TRACER_SIZE; | |
d9e54076 PZ |
3885 | |
3886 | if (copy_from_user(&buf, ubuf, cnt)) | |
3887 | return -EFAULT; | |
3888 | ||
3889 | buf[cnt] = 0; | |
3890 | ||
3891 | /* strip ending whitespace. */ | |
3892 | for (i = cnt - 1; i > 0 && isspace(buf[i]); i--) | |
3893 | buf[i] = 0; | |
3894 | ||
e6e7a65a FW |
3895 | err = tracing_set_tracer(buf); |
3896 | if (err) | |
3897 | return err; | |
d9e54076 | 3898 | |
cf8517cf | 3899 | *ppos += ret; |
bc0c38d1 | 3900 | |
c2931e05 | 3901 | return ret; |
bc0c38d1 SR |
3902 | } |
3903 | ||
3904 | static ssize_t | |
3905 | tracing_max_lat_read(struct file *filp, char __user *ubuf, | |
3906 | size_t cnt, loff_t *ppos) | |
3907 | { | |
3908 | unsigned long *ptr = filp->private_data; | |
3909 | char buf[64]; | |
3910 | int r; | |
3911 | ||
cffae437 | 3912 | r = snprintf(buf, sizeof(buf), "%ld\n", |
bc0c38d1 | 3913 | *ptr == (unsigned long)-1 ? -1 : nsecs_to_usecs(*ptr)); |
cffae437 SR |
3914 | if (r > sizeof(buf)) |
3915 | r = sizeof(buf); | |
4bf39a94 | 3916 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, r); |
bc0c38d1 SR |
3917 | } |
3918 | ||
3919 | static ssize_t | |
3920 | tracing_max_lat_write(struct file *filp, const char __user *ubuf, | |
3921 | size_t cnt, loff_t *ppos) | |
3922 | { | |
5e39841c | 3923 | unsigned long *ptr = filp->private_data; |
5e39841c | 3924 | unsigned long val; |
c6caeeb1 | 3925 | int ret; |
bc0c38d1 | 3926 | |
22fe9b54 PH |
3927 | ret = kstrtoul_from_user(ubuf, cnt, 10, &val); |
3928 | if (ret) | |
c6caeeb1 | 3929 | return ret; |
bc0c38d1 SR |
3930 | |
3931 | *ptr = val * 1000; | |
3932 | ||
3933 | return cnt; | |
3934 | } | |
3935 | ||
b3806b43 SR |
3936 | static int tracing_open_pipe(struct inode *inode, struct file *filp) |
3937 | { | |
23b625fa | 3938 | struct trace_array *tr = inode->i_private; |
b3806b43 | 3939 | struct trace_iterator *iter; |
b04cc6b1 | 3940 | int ret = 0; |
b3806b43 SR |
3941 | |
3942 | if (tracing_disabled) | |
3943 | return -ENODEV; | |
3944 | ||
6492334c SRRH |
3945 | if (trace_array_get(tr) < 0) |
3946 | return -ENODEV; | |
3947 | ||
b04cc6b1 FW |
3948 | mutex_lock(&trace_types_lock); |
3949 | ||
b3806b43 SR |
3950 | /* create a buffer to store the information to pass to userspace */ |
3951 | iter = kzalloc(sizeof(*iter), GFP_KERNEL); | |
b04cc6b1 FW |
3952 | if (!iter) { |
3953 | ret = -ENOMEM; | |
e45ccd09 | 3954 | __trace_array_put(tr); |
b04cc6b1 FW |
3955 | goto out; |
3956 | } | |
b3806b43 | 3957 | |
d7350c3f FW |
3958 | /* |
3959 | * We make a copy of the current tracer to avoid concurrent | |
3960 | * changes on it while we are reading. | |
3961 | */ | |
3962 | iter->trace = kmalloc(sizeof(*iter->trace), GFP_KERNEL); | |
3963 | if (!iter->trace) { | |
3964 | ret = -ENOMEM; | |
3965 | goto fail; | |
3966 | } | |
2b6080f2 | 3967 | *iter->trace = *tr->current_trace; |
d7350c3f | 3968 | |
4462344e | 3969 | if (!alloc_cpumask_var(&iter->started, GFP_KERNEL)) { |
b04cc6b1 | 3970 | ret = -ENOMEM; |
d7350c3f | 3971 | goto fail; |
4462344e RR |
3972 | } |
3973 | ||
a309720c | 3974 | /* trace pipe does not show start of buffer */ |
4462344e | 3975 | cpumask_setall(iter->started); |
a309720c | 3976 | |
112f38a7 SR |
3977 | if (trace_flags & TRACE_ITER_LATENCY_FMT) |
3978 | iter->iter_flags |= TRACE_FILE_LAT_FMT; | |
3979 | ||
8be0709f | 3980 | /* Output in nanoseconds only if we are using a clock in nanoseconds. */ |
58e8eedf | 3981 | if (trace_clocks[tr->clock_id].in_ns) |
8be0709f DS |
3982 | iter->iter_flags |= TRACE_FILE_TIME_IN_NS; |
3983 | ||
23b625fa ON |
3984 | iter->tr = tr; |
3985 | iter->trace_buffer = &tr->trace_buffer; | |
3986 | iter->cpu_file = tracing_get_cpu(inode); | |
d7350c3f | 3987 | mutex_init(&iter->mutex); |
b3806b43 SR |
3988 | filp->private_data = iter; |
3989 | ||
107bad8b SR |
3990 | if (iter->trace->pipe_open) |
3991 | iter->trace->pipe_open(iter); | |
107bad8b | 3992 | |
b444786f | 3993 | nonseekable_open(inode, filp); |
b04cc6b1 FW |
3994 | out: |
3995 | mutex_unlock(&trace_types_lock); | |
3996 | return ret; | |
d7350c3f FW |
3997 | |
3998 | fail: | |
3999 | kfree(iter->trace); | |
4000 | kfree(iter); | |
6492334c | 4001 | __trace_array_put(tr); |
d7350c3f FW |
4002 | mutex_unlock(&trace_types_lock); |
4003 | return ret; | |
b3806b43 SR |
4004 | } |
4005 | ||
4006 | static int tracing_release_pipe(struct inode *inode, struct file *file) | |
4007 | { | |
4008 | struct trace_iterator *iter = file->private_data; | |
23b625fa | 4009 | struct trace_array *tr = inode->i_private; |
b3806b43 | 4010 | |
b04cc6b1 FW |
4011 | mutex_lock(&trace_types_lock); |
4012 | ||
29bf4a5e | 4013 | if (iter->trace->pipe_close) |
c521efd1 SR |
4014 | iter->trace->pipe_close(iter); |
4015 | ||
b04cc6b1 FW |
4016 | mutex_unlock(&trace_types_lock); |
4017 | ||
4462344e | 4018 | free_cpumask_var(iter->started); |
d7350c3f FW |
4019 | mutex_destroy(&iter->mutex); |
4020 | kfree(iter->trace); | |
b3806b43 | 4021 | kfree(iter); |
b3806b43 | 4022 | |
6492334c SRRH |
4023 | trace_array_put(tr); |
4024 | ||
b3806b43 SR |
4025 | return 0; |
4026 | } | |
4027 | ||
2a2cc8f7 | 4028 | static unsigned int |
cc60cdc9 | 4029 | trace_poll(struct trace_iterator *iter, struct file *filp, poll_table *poll_table) |
2a2cc8f7 | 4030 | { |
15693458 SRRH |
4031 | /* Iterators are static, they should be filled or empty */ |
4032 | if (trace_buffer_iter(iter, iter->cpu_file)) | |
4033 | return POLLIN | POLLRDNORM; | |
2a2cc8f7 | 4034 | |
15693458 | 4035 | if (trace_flags & TRACE_ITER_BLOCK) |
2a2cc8f7 SSP |
4036 | /* |
4037 | * Always select as readable when in blocking mode | |
4038 | */ | |
4039 | return POLLIN | POLLRDNORM; | |
15693458 | 4040 | else |
12883efb | 4041 | return ring_buffer_poll_wait(iter->trace_buffer->buffer, iter->cpu_file, |
15693458 | 4042 | filp, poll_table); |
2a2cc8f7 | 4043 | } |
2a2cc8f7 | 4044 | |
cc60cdc9 SR |
4045 | static unsigned int |
4046 | tracing_poll_pipe(struct file *filp, poll_table *poll_table) | |
4047 | { | |
4048 | struct trace_iterator *iter = filp->private_data; | |
4049 | ||
4050 | return trace_poll(iter, filp, poll_table); | |
2a2cc8f7 SSP |
4051 | } |
4052 | ||
6eaaa5d5 FW |
4053 | /* |
4054 | * This is a make-shift waitqueue. | |
4055 | * A tracer might use this callback on some rare cases: | |
4056 | * | |
4057 | * 1) the current tracer might hold the runqueue lock when it wakes up | |
4058 | * a reader, hence a deadlock (sched, function, and function graph tracers) | |
4059 | * 2) the function tracers, trace all functions, we don't want | |
4060 | * the overhead of calling wake_up and friends | |
4061 | * (and tracing them too) | |
4062 | * | |
4063 | * Anyway, this is really very primitive wakeup. | |
4064 | */ | |
561237e4 | 4065 | int poll_wait_pipe(struct trace_iterator *iter) |
6eaaa5d5 FW |
4066 | { |
4067 | set_current_state(TASK_INTERRUPTIBLE); | |
4068 | /* sleep for 100 msecs, and try again. */ | |
4069 | schedule_timeout(HZ / 10); | |
561237e4 | 4070 | return 0; |
6eaaa5d5 FW |
4071 | } |
4072 | ||
ff98781b EGM |
4073 | /* Must be called with trace_types_lock mutex held. */ |
4074 | static int tracing_wait_pipe(struct file *filp) | |
b3806b43 SR |
4075 | { |
4076 | struct trace_iterator *iter = filp->private_data; | |
561237e4 | 4077 | int ret; |
b3806b43 | 4078 | |
b3806b43 | 4079 | while (trace_empty(iter)) { |
2dc8f095 | 4080 | |
107bad8b | 4081 | if ((filp->f_flags & O_NONBLOCK)) { |
ff98781b | 4082 | return -EAGAIN; |
107bad8b | 4083 | } |
2dc8f095 | 4084 | |
d7350c3f | 4085 | mutex_unlock(&iter->mutex); |
107bad8b | 4086 | |
561237e4 | 4087 | ret = iter->trace->wait_pipe(iter); |
b3806b43 | 4088 | |
d7350c3f | 4089 | mutex_lock(&iter->mutex); |
107bad8b | 4090 | |
561237e4 SRRH |
4091 | if (ret) |
4092 | return ret; | |
4093 | ||
6eaaa5d5 | 4094 | if (signal_pending(current)) |
ff98781b | 4095 | return -EINTR; |
b3806b43 SR |
4096 | |
4097 | /* | |
250bfd3d | 4098 | * We block until we read something and tracing is disabled. |
b3806b43 SR |
4099 | * We still block if tracing is disabled, but we have never |
4100 | * read anything. This allows a user to cat this file, and | |
4101 | * then enable tracing. But after we have read something, | |
4102 | * we give an EOF when tracing is again disabled. | |
4103 | * | |
4104 | * iter->pos will be 0 if we haven't read anything. | |
4105 | */ | |
2fd821ee | 4106 | if (!tracing_is_on() && iter->pos) |
b3806b43 | 4107 | break; |
b3806b43 SR |
4108 | } |
4109 | ||
ff98781b EGM |
4110 | return 1; |
4111 | } | |
4112 | ||
4113 | /* | |
4114 | * Consumer reader. | |
4115 | */ | |
4116 | static ssize_t | |
4117 | tracing_read_pipe(struct file *filp, char __user *ubuf, | |
4118 | size_t cnt, loff_t *ppos) | |
4119 | { | |
4120 | struct trace_iterator *iter = filp->private_data; | |
2b6080f2 | 4121 | struct trace_array *tr = iter->tr; |
ff98781b EGM |
4122 | ssize_t sret; |
4123 | ||
4124 | /* return any leftover data */ | |
4125 | sret = trace_seq_to_user(&iter->seq, ubuf, cnt); | |
4126 | if (sret != -EBUSY) | |
4127 | return sret; | |
4128 | ||
f9520750 | 4129 | trace_seq_init(&iter->seq); |
ff98781b | 4130 | |
d7350c3f | 4131 | /* copy the tracer to avoid using a global lock all around */ |
ff98781b | 4132 | mutex_lock(&trace_types_lock); |
2b6080f2 SR |
4133 | if (unlikely(iter->trace->name != tr->current_trace->name)) |
4134 | *iter->trace = *tr->current_trace; | |
d7350c3f FW |
4135 | mutex_unlock(&trace_types_lock); |
4136 | ||
4137 | /* | |
4138 | * Avoid more than one consumer on a single file descriptor | |
4139 | * This is just a matter of traces coherency, the ring buffer itself | |
4140 | * is protected. | |
4141 | */ | |
4142 | mutex_lock(&iter->mutex); | |
ff98781b EGM |
4143 | if (iter->trace->read) { |
4144 | sret = iter->trace->read(iter, filp, ubuf, cnt, ppos); | |
4145 | if (sret) | |
4146 | goto out; | |
4147 | } | |
4148 | ||
4149 | waitagain: | |
4150 | sret = tracing_wait_pipe(filp); | |
4151 | if (sret <= 0) | |
4152 | goto out; | |
4153 | ||
b3806b43 | 4154 | /* stop when tracing is finished */ |
ff98781b EGM |
4155 | if (trace_empty(iter)) { |
4156 | sret = 0; | |
107bad8b | 4157 | goto out; |
ff98781b | 4158 | } |
b3806b43 SR |
4159 | |
4160 | if (cnt >= PAGE_SIZE) | |
4161 | cnt = PAGE_SIZE - 1; | |
4162 | ||
53d0aa77 | 4163 | /* reset all but tr, trace, and overruns */ |
53d0aa77 SR |
4164 | memset(&iter->seq, 0, |
4165 | sizeof(struct trace_iterator) - | |
4166 | offsetof(struct trace_iterator, seq)); | |
2d7ddf0a | 4167 | cpumask_clear(iter->started); |
4823ed7e | 4168 | iter->pos = -1; |
b3806b43 | 4169 | |
4f535968 | 4170 | trace_event_read_lock(); |
7e53bd42 | 4171 | trace_access_lock(iter->cpu_file); |
955b61e5 | 4172 | while (trace_find_next_entry_inc(iter) != NULL) { |
2c4f035f | 4173 | enum print_line_t ret; |
088b1e42 SR |
4174 | int len = iter->seq.len; |
4175 | ||
f9896bf3 | 4176 | ret = print_trace_line(iter); |
2c4f035f | 4177 | if (ret == TRACE_TYPE_PARTIAL_LINE) { |
088b1e42 SR |
4178 | /* don't print partial lines */ |
4179 | iter->seq.len = len; | |
b3806b43 | 4180 | break; |
088b1e42 | 4181 | } |
b91facc3 FW |
4182 | if (ret != TRACE_TYPE_NO_CONSUME) |
4183 | trace_consume(iter); | |
b3806b43 SR |
4184 | |
4185 | if (iter->seq.len >= cnt) | |
4186 | break; | |
ee5e51f5 JO |
4187 | |
4188 | /* | |
4189 | * Setting the full flag means we reached the trace_seq buffer | |
4190 | * size and we should leave by partial output condition above. | |
4191 | * One of the trace_seq_* functions is not used properly. | |
4192 | */ | |
4193 | WARN_ONCE(iter->seq.full, "full flag set for trace type %d", | |
4194 | iter->ent->type); | |
b3806b43 | 4195 | } |
7e53bd42 | 4196 | trace_access_unlock(iter->cpu_file); |
4f535968 | 4197 | trace_event_read_unlock(); |
b3806b43 | 4198 | |
b3806b43 | 4199 | /* Now copy what we have to the user */ |
6c6c2796 PP |
4200 | sret = trace_seq_to_user(&iter->seq, ubuf, cnt); |
4201 | if (iter->seq.readpos >= iter->seq.len) | |
f9520750 | 4202 | trace_seq_init(&iter->seq); |
9ff4b974 PP |
4203 | |
4204 | /* | |
25985edc | 4205 | * If there was nothing to send to user, in spite of consuming trace |
9ff4b974 PP |
4206 | * entries, go back to wait for more entries. |
4207 | */ | |
6c6c2796 | 4208 | if (sret == -EBUSY) |
9ff4b974 | 4209 | goto waitagain; |
b3806b43 | 4210 | |
107bad8b | 4211 | out: |
d7350c3f | 4212 | mutex_unlock(&iter->mutex); |
107bad8b | 4213 | |
6c6c2796 | 4214 | return sret; |
b3806b43 SR |
4215 | } |
4216 | ||
3c56819b EGM |
4217 | static void tracing_pipe_buf_release(struct pipe_inode_info *pipe, |
4218 | struct pipe_buffer *buf) | |
4219 | { | |
4220 | __free_page(buf->page); | |
4221 | } | |
4222 | ||
4223 | static void tracing_spd_release_pipe(struct splice_pipe_desc *spd, | |
4224 | unsigned int idx) | |
4225 | { | |
4226 | __free_page(spd->pages[idx]); | |
4227 | } | |
4228 | ||
28dfef8f | 4229 | static const struct pipe_buf_operations tracing_pipe_buf_ops = { |
34cd4998 SR |
4230 | .can_merge = 0, |
4231 | .map = generic_pipe_buf_map, | |
4232 | .unmap = generic_pipe_buf_unmap, | |
4233 | .confirm = generic_pipe_buf_confirm, | |
4234 | .release = tracing_pipe_buf_release, | |
4235 | .steal = generic_pipe_buf_steal, | |
4236 | .get = generic_pipe_buf_get, | |
3c56819b EGM |
4237 | }; |
4238 | ||
34cd4998 | 4239 | static size_t |
fa7c7f6e | 4240 | tracing_fill_pipe_page(size_t rem, struct trace_iterator *iter) |
34cd4998 SR |
4241 | { |
4242 | size_t count; | |
4243 | int ret; | |
4244 | ||
4245 | /* Seq buffer is page-sized, exactly what we need. */ | |
4246 | for (;;) { | |
4247 | count = iter->seq.len; | |
4248 | ret = print_trace_line(iter); | |
4249 | count = iter->seq.len - count; | |
4250 | if (rem < count) { | |
4251 | rem = 0; | |
4252 | iter->seq.len -= count; | |
4253 | break; | |
4254 | } | |
4255 | if (ret == TRACE_TYPE_PARTIAL_LINE) { | |
4256 | iter->seq.len -= count; | |
4257 | break; | |
4258 | } | |
4259 | ||
74e7ff8c LJ |
4260 | if (ret != TRACE_TYPE_NO_CONSUME) |
4261 | trace_consume(iter); | |
34cd4998 | 4262 | rem -= count; |
955b61e5 | 4263 | if (!trace_find_next_entry_inc(iter)) { |
34cd4998 SR |
4264 | rem = 0; |
4265 | iter->ent = NULL; | |
4266 | break; | |
4267 | } | |
4268 | } | |
4269 | ||
4270 | return rem; | |
4271 | } | |
4272 | ||
3c56819b EGM |
4273 | static ssize_t tracing_splice_read_pipe(struct file *filp, |
4274 | loff_t *ppos, | |
4275 | struct pipe_inode_info *pipe, | |
4276 | size_t len, | |
4277 | unsigned int flags) | |
4278 | { | |
35f3d14d JA |
4279 | struct page *pages_def[PIPE_DEF_BUFFERS]; |
4280 | struct partial_page partial_def[PIPE_DEF_BUFFERS]; | |
3c56819b EGM |
4281 | struct trace_iterator *iter = filp->private_data; |
4282 | struct splice_pipe_desc spd = { | |
35f3d14d JA |
4283 | .pages = pages_def, |
4284 | .partial = partial_def, | |
34cd4998 | 4285 | .nr_pages = 0, /* This gets updated below. */ |
047fe360 | 4286 | .nr_pages_max = PIPE_DEF_BUFFERS, |
34cd4998 SR |
4287 | .flags = flags, |
4288 | .ops = &tracing_pipe_buf_ops, | |
4289 | .spd_release = tracing_spd_release_pipe, | |
3c56819b | 4290 | }; |
2b6080f2 | 4291 | struct trace_array *tr = iter->tr; |
3c56819b | 4292 | ssize_t ret; |
34cd4998 | 4293 | size_t rem; |
3c56819b EGM |
4294 | unsigned int i; |
4295 | ||
35f3d14d JA |
4296 | if (splice_grow_spd(pipe, &spd)) |
4297 | return -ENOMEM; | |
4298 | ||
d7350c3f | 4299 | /* copy the tracer to avoid using a global lock all around */ |
3c56819b | 4300 | mutex_lock(&trace_types_lock); |
2b6080f2 SR |
4301 | if (unlikely(iter->trace->name != tr->current_trace->name)) |
4302 | *iter->trace = *tr->current_trace; | |
d7350c3f FW |
4303 | mutex_unlock(&trace_types_lock); |
4304 | ||
4305 | mutex_lock(&iter->mutex); | |
3c56819b EGM |
4306 | |
4307 | if (iter->trace->splice_read) { | |
4308 | ret = iter->trace->splice_read(iter, filp, | |
4309 | ppos, pipe, len, flags); | |
4310 | if (ret) | |
34cd4998 | 4311 | goto out_err; |
3c56819b EGM |
4312 | } |
4313 | ||
4314 | ret = tracing_wait_pipe(filp); | |
4315 | if (ret <= 0) | |
34cd4998 | 4316 | goto out_err; |
3c56819b | 4317 | |
955b61e5 | 4318 | if (!iter->ent && !trace_find_next_entry_inc(iter)) { |
3c56819b | 4319 | ret = -EFAULT; |
34cd4998 | 4320 | goto out_err; |
3c56819b EGM |
4321 | } |
4322 | ||
4f535968 | 4323 | trace_event_read_lock(); |
7e53bd42 | 4324 | trace_access_lock(iter->cpu_file); |
4f535968 | 4325 | |
3c56819b | 4326 | /* Fill as many pages as possible. */ |
35f3d14d JA |
4327 | for (i = 0, rem = len; i < pipe->buffers && rem; i++) { |
4328 | spd.pages[i] = alloc_page(GFP_KERNEL); | |
4329 | if (!spd.pages[i]) | |
34cd4998 | 4330 | break; |
3c56819b | 4331 | |
fa7c7f6e | 4332 | rem = tracing_fill_pipe_page(rem, iter); |
3c56819b EGM |
4333 | |
4334 | /* Copy the data into the page, so we can start over. */ | |
4335 | ret = trace_seq_to_buffer(&iter->seq, | |
35f3d14d | 4336 | page_address(spd.pages[i]), |
3c56819b EGM |
4337 | iter->seq.len); |
4338 | if (ret < 0) { | |
35f3d14d | 4339 | __free_page(spd.pages[i]); |
3c56819b EGM |
4340 | break; |
4341 | } | |
35f3d14d JA |
4342 | spd.partial[i].offset = 0; |
4343 | spd.partial[i].len = iter->seq.len; | |
3c56819b | 4344 | |
f9520750 | 4345 | trace_seq_init(&iter->seq); |
3c56819b EGM |
4346 | } |
4347 | ||
7e53bd42 | 4348 | trace_access_unlock(iter->cpu_file); |
4f535968 | 4349 | trace_event_read_unlock(); |
d7350c3f | 4350 | mutex_unlock(&iter->mutex); |
3c56819b EGM |
4351 | |
4352 | spd.nr_pages = i; | |
4353 | ||
3f3f1fce SRRH |
4354 | if (i) |
4355 | ret = splice_to_pipe(pipe, &spd); | |
4356 | else | |
4357 | ret = 0; | |
35f3d14d | 4358 | out: |
047fe360 | 4359 | splice_shrink_spd(&spd); |
35f3d14d | 4360 | return ret; |
3c56819b | 4361 | |
34cd4998 | 4362 | out_err: |
d7350c3f | 4363 | mutex_unlock(&iter->mutex); |
35f3d14d | 4364 | goto out; |
3c56819b EGM |
4365 | } |
4366 | ||
a98a3c3f SR |
4367 | static ssize_t |
4368 | tracing_entries_read(struct file *filp, char __user *ubuf, | |
4369 | size_t cnt, loff_t *ppos) | |
4370 | { | |
e5dd03c4 ON |
4371 | struct inode *inode = file_inode(filp); |
4372 | struct trace_array *tr = inode->i_private; | |
4373 | int cpu = tracing_get_cpu(inode); | |
438ced17 VN |
4374 | char buf[64]; |
4375 | int r = 0; | |
4376 | ssize_t ret; | |
a98a3c3f | 4377 | |
db526ca3 | 4378 | mutex_lock(&trace_types_lock); |
438ced17 | 4379 | |
e5dd03c4 | 4380 | if (cpu == RING_BUFFER_ALL_CPUS) { |
438ced17 VN |
4381 | int cpu, buf_size_same; |
4382 | unsigned long size; | |
4383 | ||
4384 | size = 0; | |
4385 | buf_size_same = 1; | |
4386 | /* check if all cpu sizes are same */ | |
4387 | for_each_tracing_cpu(cpu) { | |
4388 | /* fill in the size from first enabled cpu */ | |
4389 | if (size == 0) | |
12883efb SRRH |
4390 | size = per_cpu_ptr(tr->trace_buffer.data, cpu)->entries; |
4391 | if (size != per_cpu_ptr(tr->trace_buffer.data, cpu)->entries) { | |
438ced17 VN |
4392 | buf_size_same = 0; |
4393 | break; | |
4394 | } | |
4395 | } | |
4396 | ||
4397 | if (buf_size_same) { | |
4398 | if (!ring_buffer_expanded) | |
4399 | r = sprintf(buf, "%lu (expanded: %lu)\n", | |
4400 | size >> 10, | |
4401 | trace_buf_size >> 10); | |
4402 | else | |
4403 | r = sprintf(buf, "%lu\n", size >> 10); | |
4404 | } else | |
4405 | r = sprintf(buf, "X\n"); | |
4406 | } else | |
e5dd03c4 | 4407 | r = sprintf(buf, "%lu\n", per_cpu_ptr(tr->trace_buffer.data, cpu)->entries >> 10); |
438ced17 | 4408 | |
db526ca3 SR |
4409 | mutex_unlock(&trace_types_lock); |
4410 | ||
438ced17 VN |
4411 | ret = simple_read_from_buffer(ubuf, cnt, ppos, buf, r); |
4412 | return ret; | |
a98a3c3f SR |
4413 | } |
4414 | ||
4415 | static ssize_t | |
4416 | tracing_entries_write(struct file *filp, const char __user *ubuf, | |
4417 | size_t cnt, loff_t *ppos) | |
4418 | { | |
e5dd03c4 ON |
4419 | struct inode *inode = file_inode(filp); |
4420 | struct trace_array *tr = inode->i_private; | |
a98a3c3f | 4421 | unsigned long val; |
4f271a2a | 4422 | int ret; |
a98a3c3f | 4423 | |
22fe9b54 PH |
4424 | ret = kstrtoul_from_user(ubuf, cnt, 10, &val); |
4425 | if (ret) | |
c6caeeb1 | 4426 | return ret; |
a98a3c3f SR |
4427 | |
4428 | /* must have at least 1 entry */ | |
4429 | if (!val) | |
4430 | return -EINVAL; | |
4431 | ||
1696b2b0 SR |
4432 | /* value is in KB */ |
4433 | val <<= 10; | |
e5dd03c4 | 4434 | ret = tracing_resize_ring_buffer(tr, val, tracing_get_cpu(inode)); |
4f271a2a VN |
4435 | if (ret < 0) |
4436 | return ret; | |
a98a3c3f | 4437 | |
cf8517cf | 4438 | *ppos += cnt; |
a98a3c3f | 4439 | |
4f271a2a VN |
4440 | return cnt; |
4441 | } | |
bf5e6519 | 4442 | |
f81ab074 VN |
4443 | static ssize_t |
4444 | tracing_total_entries_read(struct file *filp, char __user *ubuf, | |
4445 | size_t cnt, loff_t *ppos) | |
4446 | { | |
4447 | struct trace_array *tr = filp->private_data; | |
4448 | char buf[64]; | |
4449 | int r, cpu; | |
4450 | unsigned long size = 0, expanded_size = 0; | |
4451 | ||
4452 | mutex_lock(&trace_types_lock); | |
4453 | for_each_tracing_cpu(cpu) { | |
12883efb | 4454 | size += per_cpu_ptr(tr->trace_buffer.data, cpu)->entries >> 10; |
f81ab074 VN |
4455 | if (!ring_buffer_expanded) |
4456 | expanded_size += trace_buf_size >> 10; | |
4457 | } | |
4458 | if (ring_buffer_expanded) | |
4459 | r = sprintf(buf, "%lu\n", size); | |
4460 | else | |
4461 | r = sprintf(buf, "%lu (expanded: %lu)\n", size, expanded_size); | |
4462 | mutex_unlock(&trace_types_lock); | |
4463 | ||
4464 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, r); | |
4465 | } | |
4466 | ||
4f271a2a VN |
4467 | static ssize_t |
4468 | tracing_free_buffer_write(struct file *filp, const char __user *ubuf, | |
4469 | size_t cnt, loff_t *ppos) | |
4470 | { | |
4471 | /* | |
4472 | * There is no need to read what the user has written, this function | |
4473 | * is just to make sure that there is no error when "echo" is used | |
4474 | */ | |
4475 | ||
4476 | *ppos += cnt; | |
a98a3c3f SR |
4477 | |
4478 | return cnt; | |
4479 | } | |
4480 | ||
4f271a2a VN |
4481 | static int |
4482 | tracing_free_buffer_release(struct inode *inode, struct file *filp) | |
4483 | { | |
2b6080f2 SR |
4484 | struct trace_array *tr = inode->i_private; |
4485 | ||
cf30cf67 SR |
4486 | /* disable tracing ? */ |
4487 | if (trace_flags & TRACE_ITER_STOP_ON_FREE) | |
e25d4586 | 4488 | tracer_tracing_off(tr); |
4f271a2a | 4489 | /* resize the ring buffer to 0 */ |
2b6080f2 | 4490 | tracing_resize_ring_buffer(tr, 0, RING_BUFFER_ALL_CPUS); |
4f271a2a | 4491 | |
6492334c SRRH |
4492 | trace_array_put(tr); |
4493 | ||
4f271a2a VN |
4494 | return 0; |
4495 | } | |
4496 | ||
5bf9a1ee PP |
4497 | static ssize_t |
4498 | tracing_mark_write(struct file *filp, const char __user *ubuf, | |
4499 | size_t cnt, loff_t *fpos) | |
4500 | { | |
d696b58c | 4501 | unsigned long addr = (unsigned long)ubuf; |
b7f15519 | 4502 | struct trace_array *tr = filp->private_data; |
d696b58c SR |
4503 | struct ring_buffer_event *event; |
4504 | struct ring_buffer *buffer; | |
4505 | struct print_entry *entry; | |
4506 | unsigned long irq_flags; | |
4507 | struct page *pages[2]; | |
6edb2a8a | 4508 | void *map_page[2]; |
d696b58c SR |
4509 | int nr_pages = 1; |
4510 | ssize_t written; | |
d696b58c SR |
4511 | int offset; |
4512 | int size; | |
4513 | int len; | |
4514 | int ret; | |
6edb2a8a | 4515 | int i; |
5bf9a1ee | 4516 | |
c76f0694 | 4517 | if (tracing_disabled) |
5bf9a1ee PP |
4518 | return -EINVAL; |
4519 | ||
5224c3a3 MSB |
4520 | if (!(trace_flags & TRACE_ITER_MARKERS)) |
4521 | return -EINVAL; | |
4522 | ||
5bf9a1ee PP |
4523 | if (cnt > TRACE_BUF_SIZE) |
4524 | cnt = TRACE_BUF_SIZE; | |
4525 | ||
d696b58c SR |
4526 | /* |
4527 | * Userspace is injecting traces into the kernel trace buffer. | |
4528 | * We want to be as non intrusive as possible. | |
4529 | * To do so, we do not want to allocate any special buffers | |
4530 | * or take any locks, but instead write the userspace data | |
4531 | * straight into the ring buffer. | |
4532 | * | |
4533 | * First we need to pin the userspace buffer into memory, | |
4534 | * which, most likely it is, because it just referenced it. | |
4535 | * But there's no guarantee that it is. By using get_user_pages_fast() | |
4536 | * and kmap_atomic/kunmap_atomic() we can get access to the | |
4537 | * pages directly. We then write the data directly into the | |
4538 | * ring buffer. | |
4539 | */ | |
4540 | BUILD_BUG_ON(TRACE_BUF_SIZE >= PAGE_SIZE); | |
5bf9a1ee | 4541 | |
d696b58c SR |
4542 | /* check if we cross pages */ |
4543 | if ((addr & PAGE_MASK) != ((addr + cnt) & PAGE_MASK)) | |
4544 | nr_pages = 2; | |
4545 | ||
4546 | offset = addr & (PAGE_SIZE - 1); | |
4547 | addr &= PAGE_MASK; | |
4548 | ||
4549 | ret = get_user_pages_fast(addr, nr_pages, 0, pages); | |
4550 | if (ret < nr_pages) { | |
4551 | while (--ret >= 0) | |
4552 | put_page(pages[ret]); | |
4553 | written = -EFAULT; | |
4554 | goto out; | |
5bf9a1ee | 4555 | } |
d696b58c | 4556 | |
6edb2a8a SR |
4557 | for (i = 0; i < nr_pages; i++) |
4558 | map_page[i] = kmap_atomic(pages[i]); | |
d696b58c SR |
4559 | |
4560 | local_save_flags(irq_flags); | |
4561 | size = sizeof(*entry) + cnt + 2; /* possible \n added */ | |
b7f15519 | 4562 | buffer = tr->trace_buffer.buffer; |
d696b58c SR |
4563 | event = trace_buffer_lock_reserve(buffer, TRACE_PRINT, size, |
4564 | irq_flags, preempt_count()); | |
4565 | if (!event) { | |
4566 | /* Ring buffer disabled, return as if not open for write */ | |
4567 | written = -EBADF; | |
4568 | goto out_unlock; | |
5bf9a1ee | 4569 | } |
d696b58c SR |
4570 | |
4571 | entry = ring_buffer_event_data(event); | |
4572 | entry->ip = _THIS_IP_; | |
4573 | ||
4574 | if (nr_pages == 2) { | |
4575 | len = PAGE_SIZE - offset; | |
6edb2a8a SR |
4576 | memcpy(&entry->buf, map_page[0] + offset, len); |
4577 | memcpy(&entry->buf[len], map_page[1], cnt - len); | |
c13d2f7c | 4578 | } else |
6edb2a8a | 4579 | memcpy(&entry->buf, map_page[0] + offset, cnt); |
5bf9a1ee | 4580 | |
d696b58c SR |
4581 | if (entry->buf[cnt - 1] != '\n') { |
4582 | entry->buf[cnt] = '\n'; | |
4583 | entry->buf[cnt + 1] = '\0'; | |
4584 | } else | |
4585 | entry->buf[cnt] = '\0'; | |
4586 | ||
7ffbd48d | 4587 | __buffer_unlock_commit(buffer, event); |
5bf9a1ee | 4588 | |
d696b58c | 4589 | written = cnt; |
5bf9a1ee | 4590 | |
d696b58c | 4591 | *fpos += written; |
1aa54bca | 4592 | |
d696b58c | 4593 | out_unlock: |
0d998434 | 4594 | for (i = nr_pages - 1; i >= 0; i--) { |
6edb2a8a SR |
4595 | kunmap_atomic(map_page[i]); |
4596 | put_page(pages[i]); | |
4597 | } | |
d696b58c | 4598 | out: |
1aa54bca | 4599 | return written; |
5bf9a1ee PP |
4600 | } |
4601 | ||
13f16d20 | 4602 | static int tracing_clock_show(struct seq_file *m, void *v) |
5079f326 | 4603 | { |
2b6080f2 | 4604 | struct trace_array *tr = m->private; |
5079f326 Z |
4605 | int i; |
4606 | ||
4607 | for (i = 0; i < ARRAY_SIZE(trace_clocks); i++) | |
13f16d20 | 4608 | seq_printf(m, |
5079f326 | 4609 | "%s%s%s%s", i ? " " : "", |
2b6080f2 SR |
4610 | i == tr->clock_id ? "[" : "", trace_clocks[i].name, |
4611 | i == tr->clock_id ? "]" : ""); | |
13f16d20 | 4612 | seq_putc(m, '\n'); |
5079f326 | 4613 | |
13f16d20 | 4614 | return 0; |
5079f326 Z |
4615 | } |
4616 | ||
4617 | static ssize_t tracing_clock_write(struct file *filp, const char __user *ubuf, | |
4618 | size_t cnt, loff_t *fpos) | |
4619 | { | |
2b6080f2 SR |
4620 | struct seq_file *m = filp->private_data; |
4621 | struct trace_array *tr = m->private; | |
5079f326 Z |
4622 | char buf[64]; |
4623 | const char *clockstr; | |
4624 | int i; | |
4625 | ||
4626 | if (cnt >= sizeof(buf)) | |
4627 | return -EINVAL; | |
4628 | ||
4629 | if (copy_from_user(&buf, ubuf, cnt)) | |
4630 | return -EFAULT; | |
4631 | ||
4632 | buf[cnt] = 0; | |
4633 | ||
4634 | clockstr = strstrip(buf); | |
4635 | ||
4636 | for (i = 0; i < ARRAY_SIZE(trace_clocks); i++) { | |
4637 | if (strcmp(trace_clocks[i].name, clockstr) == 0) | |
4638 | break; | |
4639 | } | |
4640 | if (i == ARRAY_SIZE(trace_clocks)) | |
4641 | return -EINVAL; | |
4642 | ||
5079f326 Z |
4643 | mutex_lock(&trace_types_lock); |
4644 | ||
2b6080f2 SR |
4645 | tr->clock_id = i; |
4646 | ||
12883efb | 4647 | ring_buffer_set_clock(tr->trace_buffer.buffer, trace_clocks[i].func); |
5079f326 | 4648 | |
60303ed3 DS |
4649 | /* |
4650 | * New clock may not be consistent with the previous clock. | |
4651 | * Reset the buffer so that it doesn't have incomparable timestamps. | |
4652 | */ | |
e88512e7 | 4653 | tracing_reset_online_cpus(&tr->trace_buffer); |
12883efb SRRH |
4654 | |
4655 | #ifdef CONFIG_TRACER_MAX_TRACE | |
4656 | if (tr->flags & TRACE_ARRAY_FL_GLOBAL && tr->max_buffer.buffer) | |
4657 | ring_buffer_set_clock(tr->max_buffer.buffer, trace_clocks[i].func); | |
e88512e7 | 4658 | tracing_reset_online_cpus(&tr->max_buffer); |
12883efb | 4659 | #endif |
60303ed3 | 4660 | |
5079f326 Z |
4661 | mutex_unlock(&trace_types_lock); |
4662 | ||
4663 | *fpos += cnt; | |
4664 | ||
4665 | return cnt; | |
4666 | } | |
4667 | ||
13f16d20 LZ |
4668 | static int tracing_clock_open(struct inode *inode, struct file *file) |
4669 | { | |
6492334c SRRH |
4670 | struct trace_array *tr = inode->i_private; |
4671 | int ret; | |
4672 | ||
13f16d20 LZ |
4673 | if (tracing_disabled) |
4674 | return -ENODEV; | |
2b6080f2 | 4675 | |
6492334c SRRH |
4676 | if (trace_array_get(tr)) |
4677 | return -ENODEV; | |
4678 | ||
4679 | ret = single_open(file, tracing_clock_show, inode->i_private); | |
4680 | if (ret < 0) | |
4681 | trace_array_put(tr); | |
4682 | ||
4683 | return ret; | |
13f16d20 LZ |
4684 | } |
4685 | ||
6de58e62 SRRH |
4686 | struct ftrace_buffer_info { |
4687 | struct trace_iterator iter; | |
4688 | void *spare; | |
4689 | unsigned int read; | |
4690 | }; | |
4691 | ||
debdd57f HT |
4692 | #ifdef CONFIG_TRACER_SNAPSHOT |
4693 | static int tracing_snapshot_open(struct inode *inode, struct file *file) | |
4694 | { | |
7272711a | 4695 | struct trace_array *tr = inode->i_private; |
debdd57f | 4696 | struct trace_iterator *iter; |
2b6080f2 | 4697 | struct seq_file *m; |
debdd57f HT |
4698 | int ret = 0; |
4699 | ||
59d8f488 SRRH |
4700 | if (trace_array_get(tr) < 0) |
4701 | return -ENODEV; | |
4702 | ||
debdd57f | 4703 | if (file->f_mode & FMODE_READ) { |
7272711a | 4704 | iter = __tracing_open(inode, file, true); |
debdd57f HT |
4705 | if (IS_ERR(iter)) |
4706 | ret = PTR_ERR(iter); | |
2b6080f2 SR |
4707 | } else { |
4708 | /* Writes still need the seq_file to hold the private data */ | |
e45ccd09 | 4709 | ret = -ENOMEM; |
2b6080f2 SR |
4710 | m = kzalloc(sizeof(*m), GFP_KERNEL); |
4711 | if (!m) | |
e45ccd09 | 4712 | goto out; |
2b6080f2 SR |
4713 | iter = kzalloc(sizeof(*iter), GFP_KERNEL); |
4714 | if (!iter) { | |
4715 | kfree(m); | |
e45ccd09 | 4716 | goto out; |
2b6080f2 | 4717 | } |
e45ccd09 AL |
4718 | ret = 0; |
4719 | ||
59d8f488 | 4720 | iter->tr = tr; |
7272711a ON |
4721 | iter->trace_buffer = &tr->max_buffer; |
4722 | iter->cpu_file = tracing_get_cpu(inode); | |
2b6080f2 SR |
4723 | m->private = iter; |
4724 | file->private_data = m; | |
debdd57f | 4725 | } |
e45ccd09 | 4726 | out: |
59d8f488 SRRH |
4727 | if (ret < 0) |
4728 | trace_array_put(tr); | |
4729 | ||
debdd57f HT |
4730 | return ret; |
4731 | } | |
4732 | ||
4733 | static ssize_t | |
4734 | tracing_snapshot_write(struct file *filp, const char __user *ubuf, size_t cnt, | |
4735 | loff_t *ppos) | |
4736 | { | |
2b6080f2 SR |
4737 | struct seq_file *m = filp->private_data; |
4738 | struct trace_iterator *iter = m->private; | |
4739 | struct trace_array *tr = iter->tr; | |
debdd57f HT |
4740 | unsigned long val; |
4741 | int ret; | |
4742 | ||
4743 | ret = tracing_update_buffers(); | |
4744 | if (ret < 0) | |
4745 | return ret; | |
4746 | ||
4747 | ret = kstrtoul_from_user(ubuf, cnt, 10, &val); | |
4748 | if (ret) | |
4749 | return ret; | |
4750 | ||
4751 | mutex_lock(&trace_types_lock); | |
4752 | ||
2b6080f2 | 4753 | if (tr->current_trace->use_max_tr) { |
debdd57f HT |
4754 | ret = -EBUSY; |
4755 | goto out; | |
4756 | } | |
4757 | ||
4758 | switch (val) { | |
4759 | case 0: | |
f1affcaa SRRH |
4760 | if (iter->cpu_file != RING_BUFFER_ALL_CPUS) { |
4761 | ret = -EINVAL; | |
4762 | break; | |
debdd57f | 4763 | } |
3209cff4 SRRH |
4764 | if (tr->allocated_snapshot) |
4765 | free_snapshot(tr); | |
debdd57f HT |
4766 | break; |
4767 | case 1: | |
f1affcaa SRRH |
4768 | /* Only allow per-cpu swap if the ring buffer supports it */ |
4769 | #ifndef CONFIG_RING_BUFFER_ALLOW_SWAP | |
4770 | if (iter->cpu_file != RING_BUFFER_ALL_CPUS) { | |
4771 | ret = -EINVAL; | |
4772 | break; | |
4773 | } | |
4774 | #endif | |
45ad21ca | 4775 | if (!tr->allocated_snapshot) { |
3209cff4 | 4776 | ret = alloc_snapshot(tr); |
debdd57f HT |
4777 | if (ret < 0) |
4778 | break; | |
debdd57f | 4779 | } |
debdd57f HT |
4780 | local_irq_disable(); |
4781 | /* Now, we're going to swap */ | |
f1affcaa | 4782 | if (iter->cpu_file == RING_BUFFER_ALL_CPUS) |
ce9bae55 | 4783 | update_max_tr(tr, current, smp_processor_id()); |
f1affcaa | 4784 | else |
ce9bae55 | 4785 | update_max_tr_single(tr, current, iter->cpu_file); |
debdd57f HT |
4786 | local_irq_enable(); |
4787 | break; | |
4788 | default: | |
45ad21ca | 4789 | if (tr->allocated_snapshot) { |
f1affcaa SRRH |
4790 | if (iter->cpu_file == RING_BUFFER_ALL_CPUS) |
4791 | tracing_reset_online_cpus(&tr->max_buffer); | |
4792 | else | |
4793 | tracing_reset(&tr->max_buffer, iter->cpu_file); | |
4794 | } | |
debdd57f HT |
4795 | break; |
4796 | } | |
4797 | ||
4798 | if (ret >= 0) { | |
4799 | *ppos += cnt; | |
4800 | ret = cnt; | |
4801 | } | |
4802 | out: | |
4803 | mutex_unlock(&trace_types_lock); | |
4804 | return ret; | |
4805 | } | |
2b6080f2 SR |
4806 | |
4807 | static int tracing_snapshot_release(struct inode *inode, struct file *file) | |
4808 | { | |
4809 | struct seq_file *m = file->private_data; | |
59d8f488 SRRH |
4810 | int ret; |
4811 | ||
4812 | ret = tracing_release(inode, file); | |
2b6080f2 SR |
4813 | |
4814 | if (file->f_mode & FMODE_READ) | |
59d8f488 | 4815 | return ret; |
2b6080f2 SR |
4816 | |
4817 | /* If write only, the seq_file is just a stub */ | |
4818 | if (m) | |
4819 | kfree(m->private); | |
4820 | kfree(m); | |
4821 | ||
4822 | return 0; | |
4823 | } | |
4824 | ||
6de58e62 SRRH |
4825 | static int tracing_buffers_open(struct inode *inode, struct file *filp); |
4826 | static ssize_t tracing_buffers_read(struct file *filp, char __user *ubuf, | |
4827 | size_t count, loff_t *ppos); | |
4828 | static int tracing_buffers_release(struct inode *inode, struct file *file); | |
4829 | static ssize_t tracing_buffers_splice_read(struct file *file, loff_t *ppos, | |
4830 | struct pipe_inode_info *pipe, size_t len, unsigned int flags); | |
4831 | ||
4832 | static int snapshot_raw_open(struct inode *inode, struct file *filp) | |
4833 | { | |
4834 | struct ftrace_buffer_info *info; | |
4835 | int ret; | |
4836 | ||
4837 | ret = tracing_buffers_open(inode, filp); | |
4838 | if (ret < 0) | |
4839 | return ret; | |
4840 | ||
4841 | info = filp->private_data; | |
4842 | ||
4843 | if (info->iter.trace->use_max_tr) { | |
4844 | tracing_buffers_release(inode, filp); | |
4845 | return -EBUSY; | |
4846 | } | |
4847 | ||
4848 | info->iter.snapshot = true; | |
4849 | info->iter.trace_buffer = &info->iter.tr->max_buffer; | |
4850 | ||
4851 | return ret; | |
4852 | } | |
4853 | ||
debdd57f HT |
4854 | #endif /* CONFIG_TRACER_SNAPSHOT */ |
4855 | ||
4856 | ||
5e2336a0 | 4857 | static const struct file_operations tracing_max_lat_fops = { |
4bf39a94 IM |
4858 | .open = tracing_open_generic, |
4859 | .read = tracing_max_lat_read, | |
4860 | .write = tracing_max_lat_write, | |
b444786f | 4861 | .llseek = generic_file_llseek, |
bc0c38d1 SR |
4862 | }; |
4863 | ||
5e2336a0 | 4864 | static const struct file_operations set_tracer_fops = { |
4bf39a94 IM |
4865 | .open = tracing_open_generic, |
4866 | .read = tracing_set_trace_read, | |
4867 | .write = tracing_set_trace_write, | |
b444786f | 4868 | .llseek = generic_file_llseek, |
bc0c38d1 SR |
4869 | }; |
4870 | ||
5e2336a0 | 4871 | static const struct file_operations tracing_pipe_fops = { |
4bf39a94 | 4872 | .open = tracing_open_pipe, |
2a2cc8f7 | 4873 | .poll = tracing_poll_pipe, |
4bf39a94 | 4874 | .read = tracing_read_pipe, |
3c56819b | 4875 | .splice_read = tracing_splice_read_pipe, |
4bf39a94 | 4876 | .release = tracing_release_pipe, |
b444786f | 4877 | .llseek = no_llseek, |
b3806b43 SR |
4878 | }; |
4879 | ||
5e2336a0 | 4880 | static const struct file_operations tracing_entries_fops = { |
e5dd03c4 | 4881 | .open = tracing_open_generic_tr, |
a98a3c3f SR |
4882 | .read = tracing_entries_read, |
4883 | .write = tracing_entries_write, | |
b444786f | 4884 | .llseek = generic_file_llseek, |
e5dd03c4 | 4885 | .release = tracing_release_generic_tr, |
a98a3c3f SR |
4886 | }; |
4887 | ||
f81ab074 | 4888 | static const struct file_operations tracing_total_entries_fops = { |
6492334c | 4889 | .open = tracing_open_generic_tr, |
f81ab074 VN |
4890 | .read = tracing_total_entries_read, |
4891 | .llseek = generic_file_llseek, | |
6492334c | 4892 | .release = tracing_release_generic_tr, |
f81ab074 VN |
4893 | }; |
4894 | ||
4f271a2a | 4895 | static const struct file_operations tracing_free_buffer_fops = { |
6492334c | 4896 | .open = tracing_open_generic_tr, |
4f271a2a VN |
4897 | .write = tracing_free_buffer_write, |
4898 | .release = tracing_free_buffer_release, | |
4899 | }; | |
4900 | ||
5e2336a0 | 4901 | static const struct file_operations tracing_mark_fops = { |
6492334c | 4902 | .open = tracing_open_generic_tr, |
5bf9a1ee | 4903 | .write = tracing_mark_write, |
b444786f | 4904 | .llseek = generic_file_llseek, |
6492334c | 4905 | .release = tracing_release_generic_tr, |
5bf9a1ee PP |
4906 | }; |
4907 | ||
5079f326 | 4908 | static const struct file_operations trace_clock_fops = { |
13f16d20 LZ |
4909 | .open = tracing_clock_open, |
4910 | .read = seq_read, | |
4911 | .llseek = seq_lseek, | |
6492334c | 4912 | .release = tracing_single_release_tr, |
5079f326 Z |
4913 | .write = tracing_clock_write, |
4914 | }; | |
4915 | ||
debdd57f HT |
4916 | #ifdef CONFIG_TRACER_SNAPSHOT |
4917 | static const struct file_operations snapshot_fops = { | |
4918 | .open = tracing_snapshot_open, | |
4919 | .read = seq_read, | |
4920 | .write = tracing_snapshot_write, | |
4921 | .llseek = tracing_seek, | |
2b6080f2 | 4922 | .release = tracing_snapshot_release, |
debdd57f | 4923 | }; |
debdd57f | 4924 | |
6de58e62 SRRH |
4925 | static const struct file_operations snapshot_raw_fops = { |
4926 | .open = snapshot_raw_open, | |
4927 | .read = tracing_buffers_read, | |
4928 | .release = tracing_buffers_release, | |
4929 | .splice_read = tracing_buffers_splice_read, | |
4930 | .llseek = no_llseek, | |
2cadf913 SR |
4931 | }; |
4932 | ||
6de58e62 SRRH |
4933 | #endif /* CONFIG_TRACER_SNAPSHOT */ |
4934 | ||
2cadf913 SR |
4935 | static int tracing_buffers_open(struct inode *inode, struct file *filp) |
4936 | { | |
92b6279e | 4937 | struct trace_array *tr = inode->i_private; |
2cadf913 | 4938 | struct ftrace_buffer_info *info; |
6492334c | 4939 | int ret; |
2cadf913 SR |
4940 | |
4941 | if (tracing_disabled) | |
4942 | return -ENODEV; | |
4943 | ||
6492334c SRRH |
4944 | if (trace_array_get(tr) < 0) |
4945 | return -ENODEV; | |
4946 | ||
2cadf913 | 4947 | info = kzalloc(sizeof(*info), GFP_KERNEL); |
6492334c SRRH |
4948 | if (!info) { |
4949 | trace_array_put(tr); | |
2cadf913 | 4950 | return -ENOMEM; |
6492334c | 4951 | } |
2cadf913 | 4952 | |
a695cb58 SRRH |
4953 | mutex_lock(&trace_types_lock); |
4954 | ||
cc60cdc9 | 4955 | info->iter.tr = tr; |
92b6279e | 4956 | info->iter.cpu_file = tracing_get_cpu(inode); |
b627344f | 4957 | info->iter.trace = tr->current_trace; |
12883efb | 4958 | info->iter.trace_buffer = &tr->trace_buffer; |
cc60cdc9 | 4959 | info->spare = NULL; |
2cadf913 | 4960 | /* Force reading ring buffer for first read */ |
cc60cdc9 | 4961 | info->read = (unsigned int)-1; |
2cadf913 SR |
4962 | |
4963 | filp->private_data = info; | |
4964 | ||
a695cb58 SRRH |
4965 | mutex_unlock(&trace_types_lock); |
4966 | ||
6492334c SRRH |
4967 | ret = nonseekable_open(inode, filp); |
4968 | if (ret < 0) | |
4969 | trace_array_put(tr); | |
4970 | ||
4971 | return ret; | |
2cadf913 SR |
4972 | } |
4973 | ||
cc60cdc9 SR |
4974 | static unsigned int |
4975 | tracing_buffers_poll(struct file *filp, poll_table *poll_table) | |
4976 | { | |
4977 | struct ftrace_buffer_info *info = filp->private_data; | |
4978 | struct trace_iterator *iter = &info->iter; | |
4979 | ||
4980 | return trace_poll(iter, filp, poll_table); | |
4981 | } | |
4982 | ||
2cadf913 SR |
4983 | static ssize_t |
4984 | tracing_buffers_read(struct file *filp, char __user *ubuf, | |
4985 | size_t count, loff_t *ppos) | |
4986 | { | |
4987 | struct ftrace_buffer_info *info = filp->private_data; | |
cc60cdc9 | 4988 | struct trace_iterator *iter = &info->iter; |
2cadf913 | 4989 | ssize_t ret; |
6de58e62 | 4990 | ssize_t size; |
2cadf913 | 4991 | |
2dc5d12b SR |
4992 | if (!count) |
4993 | return 0; | |
4994 | ||
6de58e62 SRRH |
4995 | mutex_lock(&trace_types_lock); |
4996 | ||
4997 | #ifdef CONFIG_TRACER_MAX_TRACE | |
4998 | if (iter->snapshot && iter->tr->current_trace->use_max_tr) { | |
4999 | size = -EBUSY; | |
5000 | goto out_unlock; | |
5001 | } | |
5002 | #endif | |
5003 | ||
ddd538f3 | 5004 | if (!info->spare) |
12883efb SRRH |
5005 | info->spare = ring_buffer_alloc_read_page(iter->trace_buffer->buffer, |
5006 | iter->cpu_file); | |
6de58e62 | 5007 | size = -ENOMEM; |
ddd538f3 | 5008 | if (!info->spare) |
6de58e62 | 5009 | goto out_unlock; |
ddd538f3 | 5010 | |
2cadf913 SR |
5011 | /* Do we have previous read data to read? */ |
5012 | if (info->read < PAGE_SIZE) | |
5013 | goto read; | |
5014 | ||
b627344f | 5015 | again: |
cc60cdc9 | 5016 | trace_access_lock(iter->cpu_file); |
12883efb | 5017 | ret = ring_buffer_read_page(iter->trace_buffer->buffer, |
2cadf913 SR |
5018 | &info->spare, |
5019 | count, | |
cc60cdc9 SR |
5020 | iter->cpu_file, 0); |
5021 | trace_access_unlock(iter->cpu_file); | |
2cadf913 | 5022 | |
b627344f SR |
5023 | if (ret < 0) { |
5024 | if (trace_empty(iter)) { | |
6de58e62 SRRH |
5025 | if ((filp->f_flags & O_NONBLOCK)) { |
5026 | size = -EAGAIN; | |
5027 | goto out_unlock; | |
5028 | } | |
5029 | mutex_unlock(&trace_types_lock); | |
561237e4 | 5030 | ret = iter->trace->wait_pipe(iter); |
6de58e62 | 5031 | mutex_lock(&trace_types_lock); |
561237e4 SRRH |
5032 | if (ret) { |
5033 | size = ret; | |
5034 | goto out_unlock; | |
5035 | } | |
6de58e62 SRRH |
5036 | if (signal_pending(current)) { |
5037 | size = -EINTR; | |
5038 | goto out_unlock; | |
5039 | } | |
b627344f SR |
5040 | goto again; |
5041 | } | |
6de58e62 SRRH |
5042 | size = 0; |
5043 | goto out_unlock; | |
b627344f | 5044 | } |
436fc280 | 5045 | |
436fc280 | 5046 | info->read = 0; |
b627344f | 5047 | read: |
2cadf913 SR |
5048 | size = PAGE_SIZE - info->read; |
5049 | if (size > count) | |
5050 | size = count; | |
5051 | ||
5052 | ret = copy_to_user(ubuf, info->spare + info->read, size); | |
6de58e62 SRRH |
5053 | if (ret == size) { |
5054 | size = -EFAULT; | |
5055 | goto out_unlock; | |
5056 | } | |
2dc5d12b SR |
5057 | size -= ret; |
5058 | ||
2cadf913 SR |
5059 | *ppos += size; |
5060 | info->read += size; | |
5061 | ||
6de58e62 SRRH |
5062 | out_unlock: |
5063 | mutex_unlock(&trace_types_lock); | |
5064 | ||
2cadf913 SR |
5065 | return size; |
5066 | } | |
5067 | ||
5068 | static int tracing_buffers_release(struct inode *inode, struct file *file) | |
5069 | { | |
5070 | struct ftrace_buffer_info *info = file->private_data; | |
cc60cdc9 | 5071 | struct trace_iterator *iter = &info->iter; |
2cadf913 | 5072 | |
a695cb58 SRRH |
5073 | mutex_lock(&trace_types_lock); |
5074 | ||
59d8f488 | 5075 | __trace_array_put(iter->tr); |
2cadf913 | 5076 | |
ddd538f3 | 5077 | if (info->spare) |
12883efb | 5078 | ring_buffer_free_read_page(iter->trace_buffer->buffer, info->spare); |
2cadf913 SR |
5079 | kfree(info); |
5080 | ||
a695cb58 SRRH |
5081 | mutex_unlock(&trace_types_lock); |
5082 | ||
2cadf913 SR |
5083 | return 0; |
5084 | } | |
5085 | ||
5086 | struct buffer_ref { | |
5087 | struct ring_buffer *buffer; | |
5088 | void *page; | |
5089 | int ref; | |
5090 | }; | |
5091 | ||
5092 | static void buffer_pipe_buf_release(struct pipe_inode_info *pipe, | |
5093 | struct pipe_buffer *buf) | |
5094 | { | |
5095 | struct buffer_ref *ref = (struct buffer_ref *)buf->private; | |
5096 | ||
5097 | if (--ref->ref) | |
5098 | return; | |
5099 | ||
5100 | ring_buffer_free_read_page(ref->buffer, ref->page); | |
5101 | kfree(ref); | |
5102 | buf->private = 0; | |
5103 | } | |
5104 | ||
2cadf913 SR |
5105 | static void buffer_pipe_buf_get(struct pipe_inode_info *pipe, |
5106 | struct pipe_buffer *buf) | |
5107 | { | |
5108 | struct buffer_ref *ref = (struct buffer_ref *)buf->private; | |
5109 | ||
5110 | ref->ref++; | |
5111 | } | |
5112 | ||
5113 | /* Pipe buffer operations for a buffer. */ | |
28dfef8f | 5114 | static const struct pipe_buf_operations buffer_pipe_buf_ops = { |
2cadf913 SR |
5115 | .can_merge = 0, |
5116 | .map = generic_pipe_buf_map, | |
5117 | .unmap = generic_pipe_buf_unmap, | |
5118 | .confirm = generic_pipe_buf_confirm, | |
5119 | .release = buffer_pipe_buf_release, | |
d55cb6cf | 5120 | .steal = generic_pipe_buf_steal, |
2cadf913 SR |
5121 | .get = buffer_pipe_buf_get, |
5122 | }; | |
5123 | ||
5124 | /* | |
5125 | * Callback from splice_to_pipe(), if we need to release some pages | |
5126 | * at the end of the spd in case we error'ed out in filling the pipe. | |
5127 | */ | |
5128 | static void buffer_spd_release(struct splice_pipe_desc *spd, unsigned int i) | |
5129 | { | |
5130 | struct buffer_ref *ref = | |
5131 | (struct buffer_ref *)spd->partial[i].private; | |
5132 | ||
5133 | if (--ref->ref) | |
5134 | return; | |
5135 | ||
5136 | ring_buffer_free_read_page(ref->buffer, ref->page); | |
5137 | kfree(ref); | |
5138 | spd->partial[i].private = 0; | |
5139 | } | |
5140 | ||
5141 | static ssize_t | |
5142 | tracing_buffers_splice_read(struct file *file, loff_t *ppos, | |
5143 | struct pipe_inode_info *pipe, size_t len, | |
5144 | unsigned int flags) | |
5145 | { | |
5146 | struct ftrace_buffer_info *info = file->private_data; | |
cc60cdc9 | 5147 | struct trace_iterator *iter = &info->iter; |
35f3d14d JA |
5148 | struct partial_page partial_def[PIPE_DEF_BUFFERS]; |
5149 | struct page *pages_def[PIPE_DEF_BUFFERS]; | |
2cadf913 | 5150 | struct splice_pipe_desc spd = { |
35f3d14d JA |
5151 | .pages = pages_def, |
5152 | .partial = partial_def, | |
047fe360 | 5153 | .nr_pages_max = PIPE_DEF_BUFFERS, |
2cadf913 SR |
5154 | .flags = flags, |
5155 | .ops = &buffer_pipe_buf_ops, | |
5156 | .spd_release = buffer_spd_release, | |
5157 | }; | |
5158 | struct buffer_ref *ref; | |
93459c6c | 5159 | int entries, size, i; |
6de58e62 | 5160 | ssize_t ret; |
2cadf913 | 5161 | |
6de58e62 SRRH |
5162 | mutex_lock(&trace_types_lock); |
5163 | ||
5164 | #ifdef CONFIG_TRACER_MAX_TRACE | |
5165 | if (iter->snapshot && iter->tr->current_trace->use_max_tr) { | |
5166 | ret = -EBUSY; | |
5167 | goto out; | |
5168 | } | |
5169 | #endif | |
5170 | ||
93cfb3c9 | 5171 | if (*ppos & (PAGE_SIZE - 1)) { |
35f3d14d JA |
5172 | ret = -EINVAL; |
5173 | goto out; | |
93cfb3c9 LJ |
5174 | } |
5175 | ||
5176 | if (len & (PAGE_SIZE - 1)) { | |
35f3d14d JA |
5177 | if (len < PAGE_SIZE) { |
5178 | ret = -EINVAL; | |
5179 | goto out; | |
5180 | } | |
93cfb3c9 LJ |
5181 | len &= PAGE_MASK; |
5182 | } | |
5183 | ||
7bb0f7e6 AV |
5184 | if (splice_grow_spd(pipe, &spd)) { |
5185 | ret = -ENOMEM; | |
5186 | goto out; | |
5187 | } | |
5188 | ||
cc60cdc9 SR |
5189 | again: |
5190 | trace_access_lock(iter->cpu_file); | |
12883efb | 5191 | entries = ring_buffer_entries_cpu(iter->trace_buffer->buffer, iter->cpu_file); |
93459c6c | 5192 | |
35f3d14d | 5193 | for (i = 0; i < pipe->buffers && len && entries; i++, len -= PAGE_SIZE) { |
2cadf913 SR |
5194 | struct page *page; |
5195 | int r; | |
5196 | ||
5197 | ref = kzalloc(sizeof(*ref), GFP_KERNEL); | |
5198 | if (!ref) | |
5199 | break; | |
5200 | ||
7267fa68 | 5201 | ref->ref = 1; |
12883efb | 5202 | ref->buffer = iter->trace_buffer->buffer; |
cc60cdc9 | 5203 | ref->page = ring_buffer_alloc_read_page(ref->buffer, iter->cpu_file); |
2cadf913 SR |
5204 | if (!ref->page) { |
5205 | kfree(ref); | |
5206 | break; | |
5207 | } | |
5208 | ||
5209 | r = ring_buffer_read_page(ref->buffer, &ref->page, | |
cc60cdc9 | 5210 | len, iter->cpu_file, 1); |
2cadf913 | 5211 | if (r < 0) { |
7ea59064 | 5212 | ring_buffer_free_read_page(ref->buffer, ref->page); |
2cadf913 SR |
5213 | kfree(ref); |
5214 | break; | |
5215 | } | |
5216 | ||
5217 | /* | |
5218 | * zero out any left over data, this is going to | |
5219 | * user land. | |
5220 | */ | |
5221 | size = ring_buffer_page_len(ref->page); | |
5222 | if (size < PAGE_SIZE) | |
5223 | memset(ref->page + size, 0, PAGE_SIZE - size); | |
5224 | ||
5225 | page = virt_to_page(ref->page); | |
5226 | ||
5227 | spd.pages[i] = page; | |
5228 | spd.partial[i].len = PAGE_SIZE; | |
5229 | spd.partial[i].offset = 0; | |
5230 | spd.partial[i].private = (unsigned long)ref; | |
5231 | spd.nr_pages++; | |
93cfb3c9 | 5232 | *ppos += PAGE_SIZE; |
93459c6c | 5233 | |
12883efb | 5234 | entries = ring_buffer_entries_cpu(iter->trace_buffer->buffer, iter->cpu_file); |
2cadf913 SR |
5235 | } |
5236 | ||
cc60cdc9 | 5237 | trace_access_unlock(iter->cpu_file); |
2cadf913 SR |
5238 | spd.nr_pages = i; |
5239 | ||
5240 | /* did we read anything? */ | |
5241 | if (!spd.nr_pages) { | |
cc60cdc9 | 5242 | if ((file->f_flags & O_NONBLOCK) || (flags & SPLICE_F_NONBLOCK)) { |
2cadf913 | 5243 | ret = -EAGAIN; |
7bb0f7e6 | 5244 | goto out_shrink; |
cc60cdc9 | 5245 | } |
6de58e62 | 5246 | mutex_unlock(&trace_types_lock); |
561237e4 | 5247 | ret = iter->trace->wait_pipe(iter); |
6de58e62 | 5248 | mutex_lock(&trace_types_lock); |
561237e4 | 5249 | if (ret) |
7bb0f7e6 | 5250 | goto out_shrink; |
cc60cdc9 SR |
5251 | if (signal_pending(current)) { |
5252 | ret = -EINTR; | |
7bb0f7e6 | 5253 | goto out_shrink; |
cc60cdc9 SR |
5254 | } |
5255 | goto again; | |
2cadf913 SR |
5256 | } |
5257 | ||
5258 | ret = splice_to_pipe(pipe, &spd); | |
7bb0f7e6 | 5259 | out_shrink: |
047fe360 | 5260 | splice_shrink_spd(&spd); |
35f3d14d | 5261 | out: |
6de58e62 SRRH |
5262 | mutex_unlock(&trace_types_lock); |
5263 | ||
2cadf913 SR |
5264 | return ret; |
5265 | } | |
5266 | ||
5267 | static const struct file_operations tracing_buffers_fops = { | |
5268 | .open = tracing_buffers_open, | |
5269 | .read = tracing_buffers_read, | |
cc60cdc9 | 5270 | .poll = tracing_buffers_poll, |
2cadf913 SR |
5271 | .release = tracing_buffers_release, |
5272 | .splice_read = tracing_buffers_splice_read, | |
5273 | .llseek = no_llseek, | |
5274 | }; | |
5275 | ||
c8d77183 SR |
5276 | static ssize_t |
5277 | tracing_stats_read(struct file *filp, char __user *ubuf, | |
5278 | size_t count, loff_t *ppos) | |
5279 | { | |
6dafb0f1 ON |
5280 | struct inode *inode = file_inode(filp); |
5281 | struct trace_array *tr = inode->i_private; | |
12883efb | 5282 | struct trace_buffer *trace_buf = &tr->trace_buffer; |
6dafb0f1 | 5283 | int cpu = tracing_get_cpu(inode); |
c8d77183 SR |
5284 | struct trace_seq *s; |
5285 | unsigned long cnt; | |
c64e148a VN |
5286 | unsigned long long t; |
5287 | unsigned long usec_rem; | |
c8d77183 | 5288 | |
e4f2d10f | 5289 | s = kmalloc(sizeof(*s), GFP_KERNEL); |
c8d77183 | 5290 | if (!s) |
a646365c | 5291 | return -ENOMEM; |
c8d77183 SR |
5292 | |
5293 | trace_seq_init(s); | |
5294 | ||
12883efb | 5295 | cnt = ring_buffer_entries_cpu(trace_buf->buffer, cpu); |
c8d77183 SR |
5296 | trace_seq_printf(s, "entries: %ld\n", cnt); |
5297 | ||
12883efb | 5298 | cnt = ring_buffer_overrun_cpu(trace_buf->buffer, cpu); |
c8d77183 SR |
5299 | trace_seq_printf(s, "overrun: %ld\n", cnt); |
5300 | ||
12883efb | 5301 | cnt = ring_buffer_commit_overrun_cpu(trace_buf->buffer, cpu); |
c8d77183 SR |
5302 | trace_seq_printf(s, "commit overrun: %ld\n", cnt); |
5303 | ||
12883efb | 5304 | cnt = ring_buffer_bytes_cpu(trace_buf->buffer, cpu); |
c64e148a VN |
5305 | trace_seq_printf(s, "bytes: %ld\n", cnt); |
5306 | ||
58e8eedf | 5307 | if (trace_clocks[tr->clock_id].in_ns) { |
11043d8b | 5308 | /* local or global for trace_clock */ |
12883efb | 5309 | t = ns2usecs(ring_buffer_oldest_event_ts(trace_buf->buffer, cpu)); |
11043d8b YY |
5310 | usec_rem = do_div(t, USEC_PER_SEC); |
5311 | trace_seq_printf(s, "oldest event ts: %5llu.%06lu\n", | |
5312 | t, usec_rem); | |
5313 | ||
12883efb | 5314 | t = ns2usecs(ring_buffer_time_stamp(trace_buf->buffer, cpu)); |
11043d8b YY |
5315 | usec_rem = do_div(t, USEC_PER_SEC); |
5316 | trace_seq_printf(s, "now ts: %5llu.%06lu\n", t, usec_rem); | |
5317 | } else { | |
5318 | /* counter or tsc mode for trace_clock */ | |
5319 | trace_seq_printf(s, "oldest event ts: %llu\n", | |
12883efb | 5320 | ring_buffer_oldest_event_ts(trace_buf->buffer, cpu)); |
c64e148a | 5321 | |
11043d8b | 5322 | trace_seq_printf(s, "now ts: %llu\n", |
12883efb | 5323 | ring_buffer_time_stamp(trace_buf->buffer, cpu)); |
11043d8b | 5324 | } |
c64e148a | 5325 | |
12883efb | 5326 | cnt = ring_buffer_dropped_events_cpu(trace_buf->buffer, cpu); |
884bfe89 SP |
5327 | trace_seq_printf(s, "dropped events: %ld\n", cnt); |
5328 | ||
12883efb | 5329 | cnt = ring_buffer_read_events_cpu(trace_buf->buffer, cpu); |
ad964704 SRRH |
5330 | trace_seq_printf(s, "read events: %ld\n", cnt); |
5331 | ||
c8d77183 SR |
5332 | count = simple_read_from_buffer(ubuf, count, ppos, s->buffer, s->len); |
5333 | ||
5334 | kfree(s); | |
5335 | ||
5336 | return count; | |
5337 | } | |
5338 | ||
5339 | static const struct file_operations tracing_stats_fops = { | |
6dafb0f1 | 5340 | .open = tracing_open_generic_tr, |
c8d77183 | 5341 | .read = tracing_stats_read, |
b444786f | 5342 | .llseek = generic_file_llseek, |
6dafb0f1 | 5343 | .release = tracing_release_generic_tr, |
c8d77183 SR |
5344 | }; |
5345 | ||
bc0c38d1 SR |
5346 | #ifdef CONFIG_DYNAMIC_FTRACE |
5347 | ||
b807c3d0 SR |
5348 | int __weak ftrace_arch_read_dyn_info(char *buf, int size) |
5349 | { | |
5350 | return 0; | |
5351 | } | |
5352 | ||
bc0c38d1 | 5353 | static ssize_t |
b807c3d0 | 5354 | tracing_read_dyn_info(struct file *filp, char __user *ubuf, |
bc0c38d1 SR |
5355 | size_t cnt, loff_t *ppos) |
5356 | { | |
a26a2a27 SR |
5357 | static char ftrace_dyn_info_buffer[1024]; |
5358 | static DEFINE_MUTEX(dyn_info_mutex); | |
bc0c38d1 | 5359 | unsigned long *p = filp->private_data; |
b807c3d0 | 5360 | char *buf = ftrace_dyn_info_buffer; |
a26a2a27 | 5361 | int size = ARRAY_SIZE(ftrace_dyn_info_buffer); |
bc0c38d1 SR |
5362 | int r; |
5363 | ||
b807c3d0 SR |
5364 | mutex_lock(&dyn_info_mutex); |
5365 | r = sprintf(buf, "%ld ", *p); | |
4bf39a94 | 5366 | |
a26a2a27 | 5367 | r += ftrace_arch_read_dyn_info(buf+r, (size-1)-r); |
b807c3d0 SR |
5368 | buf[r++] = '\n'; |
5369 | ||
5370 | r = simple_read_from_buffer(ubuf, cnt, ppos, buf, r); | |
5371 | ||
5372 | mutex_unlock(&dyn_info_mutex); | |
5373 | ||
5374 | return r; | |
bc0c38d1 SR |
5375 | } |
5376 | ||
5e2336a0 | 5377 | static const struct file_operations tracing_dyn_info_fops = { |
4bf39a94 | 5378 | .open = tracing_open_generic, |
b807c3d0 | 5379 | .read = tracing_read_dyn_info, |
b444786f | 5380 | .llseek = generic_file_llseek, |
bc0c38d1 | 5381 | }; |
77fd5c15 | 5382 | #endif /* CONFIG_DYNAMIC_FTRACE */ |
bc0c38d1 | 5383 | |
77fd5c15 SRRH |
5384 | #if defined(CONFIG_TRACER_SNAPSHOT) && defined(CONFIG_DYNAMIC_FTRACE) |
5385 | static void | |
5386 | ftrace_snapshot(unsigned long ip, unsigned long parent_ip, void **data) | |
5387 | { | |
5388 | tracing_snapshot(); | |
5389 | } | |
bc0c38d1 | 5390 | |
77fd5c15 SRRH |
5391 | static void |
5392 | ftrace_count_snapshot(unsigned long ip, unsigned long parent_ip, void **data) | |
bc0c38d1 | 5393 | { |
77fd5c15 SRRH |
5394 | unsigned long *count = (long *)data; |
5395 | ||
5396 | if (!*count) | |
5397 | return; | |
bc0c38d1 | 5398 | |
77fd5c15 SRRH |
5399 | if (*count != -1) |
5400 | (*count)--; | |
5401 | ||
5402 | tracing_snapshot(); | |
5403 | } | |
5404 | ||
5405 | static int | |
5406 | ftrace_snapshot_print(struct seq_file *m, unsigned long ip, | |
5407 | struct ftrace_probe_ops *ops, void *data) | |
5408 | { | |
5409 | long count = (long)data; | |
5410 | ||
5411 | seq_printf(m, "%ps:", (void *)ip); | |
5412 | ||
5413 | seq_printf(m, "snapshot"); | |
5414 | ||
5415 | if (count == -1) | |
5416 | seq_printf(m, ":unlimited\n"); | |
5417 | else | |
5418 | seq_printf(m, ":count=%ld\n", count); | |
5419 | ||
5420 | return 0; | |
5421 | } | |
5422 | ||
5423 | static struct ftrace_probe_ops snapshot_probe_ops = { | |
5424 | .func = ftrace_snapshot, | |
5425 | .print = ftrace_snapshot_print, | |
5426 | }; | |
5427 | ||
5428 | static struct ftrace_probe_ops snapshot_count_probe_ops = { | |
5429 | .func = ftrace_count_snapshot, | |
5430 | .print = ftrace_snapshot_print, | |
5431 | }; | |
5432 | ||
5433 | static int | |
5434 | ftrace_trace_snapshot_callback(struct ftrace_hash *hash, | |
5435 | char *glob, char *cmd, char *param, int enable) | |
5436 | { | |
5437 | struct ftrace_probe_ops *ops; | |
5438 | void *count = (void *)-1; | |
5439 | char *number; | |
5440 | int ret; | |
5441 | ||
5442 | /* hash funcs only work with set_ftrace_filter */ | |
5443 | if (!enable) | |
5444 | return -EINVAL; | |
5445 | ||
5446 | ops = param ? &snapshot_count_probe_ops : &snapshot_probe_ops; | |
5447 | ||
5448 | if (glob[0] == '!') { | |
5449 | unregister_ftrace_function_probe_func(glob+1, ops); | |
5450 | return 0; | |
5451 | } | |
5452 | ||
5453 | if (!param) | |
5454 | goto out_reg; | |
5455 | ||
5456 | number = strsep(¶m, ":"); | |
5457 | ||
5458 | if (!strlen(number)) | |
5459 | goto out_reg; | |
5460 | ||
5461 | /* | |
5462 | * We use the callback data field (which is a pointer) | |
5463 | * as our counter. | |
5464 | */ | |
5465 | ret = kstrtoul(number, 0, (unsigned long *)&count); | |
5466 | if (ret) | |
5467 | return ret; | |
5468 | ||
5469 | out_reg: | |
5470 | ret = register_ftrace_function_probe(glob, ops, count); | |
5471 | ||
5472 | if (ret >= 0) | |
5473 | alloc_snapshot(&global_trace); | |
5474 | ||
5475 | return ret < 0 ? ret : 0; | |
5476 | } | |
5477 | ||
5478 | static struct ftrace_func_command ftrace_snapshot_cmd = { | |
5479 | .name = "snapshot", | |
5480 | .func = ftrace_trace_snapshot_callback, | |
5481 | }; | |
5482 | ||
5483 | static int register_snapshot_cmd(void) | |
5484 | { | |
5485 | return register_ftrace_command(&ftrace_snapshot_cmd); | |
5486 | } | |
5487 | #else | |
5488 | static inline int register_snapshot_cmd(void) { return 0; } | |
5489 | #endif /* defined(CONFIG_TRACER_SNAPSHOT) && defined(CONFIG_DYNAMIC_FTRACE) */ | |
bc0c38d1 | 5490 | |
2b6080f2 | 5491 | struct dentry *tracing_init_dentry_tr(struct trace_array *tr) |
bc0c38d1 | 5492 | { |
2b6080f2 SR |
5493 | if (tr->dir) |
5494 | return tr->dir; | |
bc0c38d1 | 5495 | |
3e1f60b8 FW |
5496 | if (!debugfs_initialized()) |
5497 | return NULL; | |
5498 | ||
2b6080f2 SR |
5499 | if (tr->flags & TRACE_ARRAY_FL_GLOBAL) |
5500 | tr->dir = debugfs_create_dir("tracing", NULL); | |
bc0c38d1 | 5501 | |
687c878a J |
5502 | if (!tr->dir) |
5503 | pr_warn_once("Could not create debugfs directory 'tracing'\n"); | |
bc0c38d1 | 5504 | |
2b6080f2 | 5505 | return tr->dir; |
bc0c38d1 SR |
5506 | } |
5507 | ||
2b6080f2 SR |
5508 | struct dentry *tracing_init_dentry(void) |
5509 | { | |
5510 | return tracing_init_dentry_tr(&global_trace); | |
5511 | } | |
b04cc6b1 | 5512 | |
2b6080f2 | 5513 | static struct dentry *tracing_dentry_percpu(struct trace_array *tr, int cpu) |
b04cc6b1 | 5514 | { |
b04cc6b1 FW |
5515 | struct dentry *d_tracer; |
5516 | ||
2b6080f2 SR |
5517 | if (tr->percpu_dir) |
5518 | return tr->percpu_dir; | |
b04cc6b1 | 5519 | |
2b6080f2 | 5520 | d_tracer = tracing_init_dentry_tr(tr); |
b04cc6b1 FW |
5521 | if (!d_tracer) |
5522 | return NULL; | |
5523 | ||
2b6080f2 | 5524 | tr->percpu_dir = debugfs_create_dir("per_cpu", d_tracer); |
b04cc6b1 | 5525 | |
2b6080f2 SR |
5526 | WARN_ONCE(!tr->percpu_dir, |
5527 | "Could not create debugfs directory 'per_cpu/%d'\n", cpu); | |
b04cc6b1 | 5528 | |
2b6080f2 | 5529 | return tr->percpu_dir; |
b04cc6b1 FW |
5530 | } |
5531 | ||
e2d4dbe0 ON |
5532 | static struct dentry * |
5533 | trace_create_cpu_file(const char *name, umode_t mode, struct dentry *parent, | |
5534 | void *data, long cpu, const struct file_operations *fops) | |
5535 | { | |
5536 | struct dentry *ret = trace_create_file(name, mode, parent, data, fops); | |
5537 | ||
5538 | if (ret) /* See tracing_get_cpu() */ | |
5539 | ret->d_inode->i_cdev = (void *)(cpu + 1); | |
5540 | return ret; | |
5541 | } | |
5542 | ||
2b6080f2 SR |
5543 | static void |
5544 | tracing_init_debugfs_percpu(struct trace_array *tr, long cpu) | |
b04cc6b1 | 5545 | { |
2b6080f2 | 5546 | struct dentry *d_percpu = tracing_dentry_percpu(tr, cpu); |
5452af66 | 5547 | struct dentry *d_cpu; |
dd49a38c | 5548 | char cpu_dir[30]; /* 30 characters should be more than enough */ |
b04cc6b1 | 5549 | |
0a3d7ce7 NK |
5550 | if (!d_percpu) |
5551 | return; | |
5552 | ||
dd49a38c | 5553 | snprintf(cpu_dir, 30, "cpu%ld", cpu); |
8656e7a2 FW |
5554 | d_cpu = debugfs_create_dir(cpu_dir, d_percpu); |
5555 | if (!d_cpu) { | |
5556 | pr_warning("Could not create debugfs '%s' entry\n", cpu_dir); | |
5557 | return; | |
5558 | } | |
b04cc6b1 | 5559 | |
8656e7a2 | 5560 | /* per cpu trace_pipe */ |
e2d4dbe0 | 5561 | trace_create_cpu_file("trace_pipe", 0444, d_cpu, |
23b625fa | 5562 | tr, cpu, &tracing_pipe_fops); |
b04cc6b1 FW |
5563 | |
5564 | /* per cpu trace */ | |
e2d4dbe0 | 5565 | trace_create_cpu_file("trace", 0644, d_cpu, |
7272711a | 5566 | tr, cpu, &tracing_fops); |
7f96f93f | 5567 | |
e2d4dbe0 | 5568 | trace_create_cpu_file("trace_pipe_raw", 0444, d_cpu, |
92b6279e | 5569 | tr, cpu, &tracing_buffers_fops); |
7f96f93f | 5570 | |
e2d4dbe0 | 5571 | trace_create_cpu_file("stats", 0444, d_cpu, |
6dafb0f1 | 5572 | tr, cpu, &tracing_stats_fops); |
438ced17 | 5573 | |
e2d4dbe0 | 5574 | trace_create_cpu_file("buffer_size_kb", 0444, d_cpu, |
e5dd03c4 | 5575 | tr, cpu, &tracing_entries_fops); |
f1affcaa SRRH |
5576 | |
5577 | #ifdef CONFIG_TRACER_SNAPSHOT | |
e2d4dbe0 | 5578 | trace_create_cpu_file("snapshot", 0644, d_cpu, |
7272711a | 5579 | tr, cpu, &snapshot_fops); |
6de58e62 | 5580 | |
e2d4dbe0 | 5581 | trace_create_cpu_file("snapshot_raw", 0444, d_cpu, |
92b6279e | 5582 | tr, cpu, &snapshot_raw_fops); |
f1affcaa | 5583 | #endif |
b04cc6b1 FW |
5584 | } |
5585 | ||
60a11774 SR |
5586 | #ifdef CONFIG_FTRACE_SELFTEST |
5587 | /* Let selftest have access to static functions in this file */ | |
5588 | #include "trace_selftest.c" | |
5589 | #endif | |
5590 | ||
577b785f SR |
5591 | struct trace_option_dentry { |
5592 | struct tracer_opt *opt; | |
5593 | struct tracer_flags *flags; | |
2b6080f2 | 5594 | struct trace_array *tr; |
577b785f SR |
5595 | struct dentry *entry; |
5596 | }; | |
5597 | ||
5598 | static ssize_t | |
5599 | trace_options_read(struct file *filp, char __user *ubuf, size_t cnt, | |
5600 | loff_t *ppos) | |
5601 | { | |
5602 | struct trace_option_dentry *topt = filp->private_data; | |
5603 | char *buf; | |
5604 | ||
5605 | if (topt->flags->val & topt->opt->bit) | |
5606 | buf = "1\n"; | |
5607 | else | |
5608 | buf = "0\n"; | |
5609 | ||
5610 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, 2); | |
5611 | } | |
5612 | ||
5613 | static ssize_t | |
5614 | trace_options_write(struct file *filp, const char __user *ubuf, size_t cnt, | |
5615 | loff_t *ppos) | |
5616 | { | |
5617 | struct trace_option_dentry *topt = filp->private_data; | |
5618 | unsigned long val; | |
577b785f SR |
5619 | int ret; |
5620 | ||
22fe9b54 PH |
5621 | ret = kstrtoul_from_user(ubuf, cnt, 10, &val); |
5622 | if (ret) | |
577b785f SR |
5623 | return ret; |
5624 | ||
8d18eaaf LZ |
5625 | if (val != 0 && val != 1) |
5626 | return -EINVAL; | |
577b785f | 5627 | |
8d18eaaf | 5628 | if (!!(topt->flags->val & topt->opt->bit) != val) { |
577b785f | 5629 | mutex_lock(&trace_types_lock); |
2b6080f2 | 5630 | ret = __set_tracer_option(topt->tr->current_trace, topt->flags, |
c757bea9 | 5631 | topt->opt, !val); |
577b785f SR |
5632 | mutex_unlock(&trace_types_lock); |
5633 | if (ret) | |
5634 | return ret; | |
577b785f SR |
5635 | } |
5636 | ||
5637 | *ppos += cnt; | |
5638 | ||
5639 | return cnt; | |
5640 | } | |
5641 | ||
5642 | ||
5643 | static const struct file_operations trace_options_fops = { | |
5644 | .open = tracing_open_generic, | |
5645 | .read = trace_options_read, | |
5646 | .write = trace_options_write, | |
b444786f | 5647 | .llseek = generic_file_llseek, |
577b785f SR |
5648 | }; |
5649 | ||
a8259075 SR |
5650 | static ssize_t |
5651 | trace_options_core_read(struct file *filp, char __user *ubuf, size_t cnt, | |
5652 | loff_t *ppos) | |
5653 | { | |
5654 | long index = (long)filp->private_data; | |
5655 | char *buf; | |
5656 | ||
5657 | if (trace_flags & (1 << index)) | |
5658 | buf = "1\n"; | |
5659 | else | |
5660 | buf = "0\n"; | |
5661 | ||
5662 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, 2); | |
5663 | } | |
5664 | ||
5665 | static ssize_t | |
5666 | trace_options_core_write(struct file *filp, const char __user *ubuf, size_t cnt, | |
5667 | loff_t *ppos) | |
5668 | { | |
2b6080f2 | 5669 | struct trace_array *tr = &global_trace; |
a8259075 | 5670 | long index = (long)filp->private_data; |
a8259075 SR |
5671 | unsigned long val; |
5672 | int ret; | |
5673 | ||
22fe9b54 PH |
5674 | ret = kstrtoul_from_user(ubuf, cnt, 10, &val); |
5675 | if (ret) | |
a8259075 SR |
5676 | return ret; |
5677 | ||
f2d84b65 | 5678 | if (val != 0 && val != 1) |
a8259075 | 5679 | return -EINVAL; |
69d34da2 SRRH |
5680 | |
5681 | mutex_lock(&trace_types_lock); | |
2b6080f2 | 5682 | ret = set_tracer_flag(tr, 1 << index, val); |
69d34da2 | 5683 | mutex_unlock(&trace_types_lock); |
a8259075 | 5684 | |
613f04a0 SRRH |
5685 | if (ret < 0) |
5686 | return ret; | |
5687 | ||
a8259075 SR |
5688 | *ppos += cnt; |
5689 | ||
5690 | return cnt; | |
5691 | } | |
5692 | ||
a8259075 SR |
5693 | static const struct file_operations trace_options_core_fops = { |
5694 | .open = tracing_open_generic, | |
5695 | .read = trace_options_core_read, | |
5696 | .write = trace_options_core_write, | |
b444786f | 5697 | .llseek = generic_file_llseek, |
a8259075 SR |
5698 | }; |
5699 | ||
5452af66 | 5700 | struct dentry *trace_create_file(const char *name, |
f4ae40a6 | 5701 | umode_t mode, |
5452af66 FW |
5702 | struct dentry *parent, |
5703 | void *data, | |
5704 | const struct file_operations *fops) | |
5705 | { | |
5706 | struct dentry *ret; | |
5707 | ||
5708 | ret = debugfs_create_file(name, mode, parent, data, fops); | |
5709 | if (!ret) | |
5710 | pr_warning("Could not create debugfs '%s' entry\n", name); | |
5711 | ||
5712 | return ret; | |
5713 | } | |
5714 | ||
5715 | ||
2b6080f2 | 5716 | static struct dentry *trace_options_init_dentry(struct trace_array *tr) |
a8259075 SR |
5717 | { |
5718 | struct dentry *d_tracer; | |
a8259075 | 5719 | |
2b6080f2 SR |
5720 | if (tr->options) |
5721 | return tr->options; | |
a8259075 | 5722 | |
2b6080f2 | 5723 | d_tracer = tracing_init_dentry_tr(tr); |
a8259075 SR |
5724 | if (!d_tracer) |
5725 | return NULL; | |
5726 | ||
2b6080f2 SR |
5727 | tr->options = debugfs_create_dir("options", d_tracer); |
5728 | if (!tr->options) { | |
a8259075 SR |
5729 | pr_warning("Could not create debugfs directory 'options'\n"); |
5730 | return NULL; | |
5731 | } | |
5732 | ||
2b6080f2 | 5733 | return tr->options; |
a8259075 SR |
5734 | } |
5735 | ||
577b785f | 5736 | static void |
2b6080f2 SR |
5737 | create_trace_option_file(struct trace_array *tr, |
5738 | struct trace_option_dentry *topt, | |
577b785f SR |
5739 | struct tracer_flags *flags, |
5740 | struct tracer_opt *opt) | |
5741 | { | |
5742 | struct dentry *t_options; | |
577b785f | 5743 | |
2b6080f2 | 5744 | t_options = trace_options_init_dentry(tr); |
577b785f SR |
5745 | if (!t_options) |
5746 | return; | |
5747 | ||
5748 | topt->flags = flags; | |
5749 | topt->opt = opt; | |
2b6080f2 | 5750 | topt->tr = tr; |
577b785f | 5751 | |
5452af66 | 5752 | topt->entry = trace_create_file(opt->name, 0644, t_options, topt, |
577b785f SR |
5753 | &trace_options_fops); |
5754 | ||
577b785f SR |
5755 | } |
5756 | ||
5757 | static struct trace_option_dentry * | |
2b6080f2 | 5758 | create_trace_option_files(struct trace_array *tr, struct tracer *tracer) |
577b785f SR |
5759 | { |
5760 | struct trace_option_dentry *topts; | |
5761 | struct tracer_flags *flags; | |
5762 | struct tracer_opt *opts; | |
5763 | int cnt; | |
5764 | ||
5765 | if (!tracer) | |
5766 | return NULL; | |
5767 | ||
5768 | flags = tracer->flags; | |
5769 | ||
5770 | if (!flags || !flags->opts) | |
5771 | return NULL; | |
5772 | ||
5773 | opts = flags->opts; | |
5774 | ||
5775 | for (cnt = 0; opts[cnt].name; cnt++) | |
5776 | ; | |
5777 | ||
0cfe8245 | 5778 | topts = kcalloc(cnt + 1, sizeof(*topts), GFP_KERNEL); |
577b785f SR |
5779 | if (!topts) |
5780 | return NULL; | |
5781 | ||
5782 | for (cnt = 0; opts[cnt].name; cnt++) | |
2b6080f2 | 5783 | create_trace_option_file(tr, &topts[cnt], flags, |
577b785f SR |
5784 | &opts[cnt]); |
5785 | ||
5786 | return topts; | |
5787 | } | |
5788 | ||
5789 | static void | |
5790 | destroy_trace_option_files(struct trace_option_dentry *topts) | |
5791 | { | |
5792 | int cnt; | |
5793 | ||
5794 | if (!topts) | |
5795 | return; | |
5796 | ||
5797 | for (cnt = 0; topts[cnt].opt; cnt++) { | |
5798 | if (topts[cnt].entry) | |
5799 | debugfs_remove(topts[cnt].entry); | |
5800 | } | |
5801 | ||
5802 | kfree(topts); | |
5803 | } | |
5804 | ||
a8259075 | 5805 | static struct dentry * |
2b6080f2 SR |
5806 | create_trace_option_core_file(struct trace_array *tr, |
5807 | const char *option, long index) | |
a8259075 SR |
5808 | { |
5809 | struct dentry *t_options; | |
a8259075 | 5810 | |
2b6080f2 | 5811 | t_options = trace_options_init_dentry(tr); |
a8259075 SR |
5812 | if (!t_options) |
5813 | return NULL; | |
5814 | ||
5452af66 | 5815 | return trace_create_file(option, 0644, t_options, (void *)index, |
a8259075 | 5816 | &trace_options_core_fops); |
a8259075 SR |
5817 | } |
5818 | ||
2b6080f2 | 5819 | static __init void create_trace_options_dir(struct trace_array *tr) |
a8259075 SR |
5820 | { |
5821 | struct dentry *t_options; | |
a8259075 SR |
5822 | int i; |
5823 | ||
2b6080f2 | 5824 | t_options = trace_options_init_dentry(tr); |
a8259075 SR |
5825 | if (!t_options) |
5826 | return; | |
5827 | ||
5452af66 | 5828 | for (i = 0; trace_options[i]; i++) |
2b6080f2 | 5829 | create_trace_option_core_file(tr, trace_options[i], i); |
a8259075 SR |
5830 | } |
5831 | ||
499e5470 SR |
5832 | static ssize_t |
5833 | rb_simple_read(struct file *filp, char __user *ubuf, | |
5834 | size_t cnt, loff_t *ppos) | |
5835 | { | |
348f0fc2 | 5836 | struct trace_array *tr = filp->private_data; |
499e5470 SR |
5837 | char buf[64]; |
5838 | int r; | |
5839 | ||
2fd821ee | 5840 | r = tracer_tracing_is_on(tr); |
499e5470 SR |
5841 | r = sprintf(buf, "%d\n", r); |
5842 | ||
5843 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, r); | |
5844 | } | |
5845 | ||
5846 | static ssize_t | |
5847 | rb_simple_write(struct file *filp, const char __user *ubuf, | |
5848 | size_t cnt, loff_t *ppos) | |
5849 | { | |
348f0fc2 | 5850 | struct trace_array *tr = filp->private_data; |
12883efb | 5851 | struct ring_buffer *buffer = tr->trace_buffer.buffer; |
499e5470 SR |
5852 | unsigned long val; |
5853 | int ret; | |
5854 | ||
5855 | ret = kstrtoul_from_user(ubuf, cnt, 10, &val); | |
5856 | if (ret) | |
5857 | return ret; | |
5858 | ||
5859 | if (buffer) { | |
2df8f8a6 SR |
5860 | mutex_lock(&trace_types_lock); |
5861 | if (val) { | |
2fd821ee | 5862 | tracer_tracing_on(tr); |
2b6080f2 SR |
5863 | if (tr->current_trace->start) |
5864 | tr->current_trace->start(tr); | |
2df8f8a6 | 5865 | } else { |
2fd821ee | 5866 | tracer_tracing_off(tr); |
2b6080f2 SR |
5867 | if (tr->current_trace->stop) |
5868 | tr->current_trace->stop(tr); | |
2df8f8a6 SR |
5869 | } |
5870 | mutex_unlock(&trace_types_lock); | |
499e5470 SR |
5871 | } |
5872 | ||
5873 | (*ppos)++; | |
5874 | ||
5875 | return cnt; | |
5876 | } | |
5877 | ||
5878 | static const struct file_operations rb_simple_fops = { | |
6492334c | 5879 | .open = tracing_open_generic_tr, |
499e5470 SR |
5880 | .read = rb_simple_read, |
5881 | .write = rb_simple_write, | |
6492334c | 5882 | .release = tracing_release_generic_tr, |
499e5470 SR |
5883 | .llseek = default_llseek, |
5884 | }; | |
5885 | ||
277ba044 SR |
5886 | struct dentry *trace_instance_dir; |
5887 | ||
5888 | static void | |
5889 | init_tracer_debugfs(struct trace_array *tr, struct dentry *d_tracer); | |
5890 | ||
737223fb SRRH |
5891 | static void init_trace_buffers(struct trace_array *tr, struct trace_buffer *buf) |
5892 | { | |
5893 | int cpu; | |
5894 | ||
5895 | for_each_tracing_cpu(cpu) { | |
5896 | memset(per_cpu_ptr(buf->data, cpu), 0, sizeof(struct trace_array_cpu)); | |
5897 | per_cpu_ptr(buf->data, cpu)->trace_cpu.cpu = cpu; | |
5898 | per_cpu_ptr(buf->data, cpu)->trace_cpu.tr = tr; | |
5899 | } | |
5900 | } | |
5901 | ||
55034cd6 SRRH |
5902 | static int |
5903 | allocate_trace_buffer(struct trace_array *tr, struct trace_buffer *buf, int size) | |
277ba044 SR |
5904 | { |
5905 | enum ring_buffer_flags rb_flags; | |
737223fb SRRH |
5906 | |
5907 | rb_flags = trace_flags & TRACE_ITER_OVERWRITE ? RB_FL_OVERWRITE : 0; | |
5908 | ||
fb23eaf4 SRRH |
5909 | buf->tr = tr; |
5910 | ||
55034cd6 SRRH |
5911 | buf->buffer = ring_buffer_alloc(size, rb_flags); |
5912 | if (!buf->buffer) | |
5913 | return -ENOMEM; | |
737223fb | 5914 | |
55034cd6 SRRH |
5915 | buf->data = alloc_percpu(struct trace_array_cpu); |
5916 | if (!buf->data) { | |
5917 | ring_buffer_free(buf->buffer); | |
5918 | return -ENOMEM; | |
5919 | } | |
737223fb | 5920 | |
55034cd6 | 5921 | init_trace_buffers(tr, buf); |
737223fb SRRH |
5922 | |
5923 | /* Allocate the first page for all buffers */ | |
5924 | set_buffer_entries(&tr->trace_buffer, | |
5925 | ring_buffer_size(tr->trace_buffer.buffer, 0)); | |
5926 | ||
55034cd6 SRRH |
5927 | return 0; |
5928 | } | |
737223fb | 5929 | |
55034cd6 SRRH |
5930 | static int allocate_trace_buffers(struct trace_array *tr, int size) |
5931 | { | |
5932 | int ret; | |
737223fb | 5933 | |
55034cd6 SRRH |
5934 | ret = allocate_trace_buffer(tr, &tr->trace_buffer, size); |
5935 | if (ret) | |
5936 | return ret; | |
737223fb | 5937 | |
55034cd6 SRRH |
5938 | #ifdef CONFIG_TRACER_MAX_TRACE |
5939 | ret = allocate_trace_buffer(tr, &tr->max_buffer, | |
5940 | allocate_snapshot ? size : 1); | |
5941 | if (WARN_ON(ret)) { | |
737223fb | 5942 | ring_buffer_free(tr->trace_buffer.buffer); |
55034cd6 SRRH |
5943 | free_percpu(tr->trace_buffer.data); |
5944 | return -ENOMEM; | |
5945 | } | |
5946 | tr->allocated_snapshot = allocate_snapshot; | |
737223fb | 5947 | |
55034cd6 SRRH |
5948 | /* |
5949 | * Only the top level trace array gets its snapshot allocated | |
5950 | * from the kernel command line. | |
5951 | */ | |
5952 | allocate_snapshot = false; | |
737223fb | 5953 | #endif |
55034cd6 | 5954 | return 0; |
737223fb SRRH |
5955 | } |
5956 | ||
5957 | static int new_instance_create(const char *name) | |
5958 | { | |
277ba044 SR |
5959 | struct trace_array *tr; |
5960 | int ret; | |
277ba044 SR |
5961 | |
5962 | mutex_lock(&trace_types_lock); | |
5963 | ||
5964 | ret = -EEXIST; | |
5965 | list_for_each_entry(tr, &ftrace_trace_arrays, list) { | |
5966 | if (tr->name && strcmp(tr->name, name) == 0) | |
5967 | goto out_unlock; | |
5968 | } | |
5969 | ||
5970 | ret = -ENOMEM; | |
5971 | tr = kzalloc(sizeof(*tr), GFP_KERNEL); | |
5972 | if (!tr) | |
5973 | goto out_unlock; | |
5974 | ||
5975 | tr->name = kstrdup(name, GFP_KERNEL); | |
5976 | if (!tr->name) | |
5977 | goto out_free_tr; | |
5978 | ||
5979 | raw_spin_lock_init(&tr->start_lock); | |
5980 | ||
5981 | tr->current_trace = &nop_trace; | |
5982 | ||
5983 | INIT_LIST_HEAD(&tr->systems); | |
5984 | INIT_LIST_HEAD(&tr->events); | |
5985 | ||
737223fb | 5986 | if (allocate_trace_buffers(tr, trace_buf_size) < 0) |
277ba044 SR |
5987 | goto out_free_tr; |
5988 | ||
277ba044 SR |
5989 | /* Holder for file callbacks */ |
5990 | tr->trace_cpu.cpu = RING_BUFFER_ALL_CPUS; | |
5991 | tr->trace_cpu.tr = tr; | |
5992 | ||
5993 | tr->dir = debugfs_create_dir(name, trace_instance_dir); | |
5994 | if (!tr->dir) | |
5995 | goto out_free_tr; | |
5996 | ||
5997 | ret = event_trace_add_tracer(tr->dir, tr); | |
a33eb1f5 AL |
5998 | if (ret) { |
5999 | debugfs_remove_recursive(tr->dir); | |
277ba044 | 6000 | goto out_free_tr; |
a33eb1f5 | 6001 | } |
277ba044 SR |
6002 | |
6003 | init_tracer_debugfs(tr, tr->dir); | |
6004 | ||
6005 | list_add(&tr->list, &ftrace_trace_arrays); | |
6006 | ||
6007 | mutex_unlock(&trace_types_lock); | |
6008 | ||
6009 | return 0; | |
6010 | ||
6011 | out_free_tr: | |
12883efb SRRH |
6012 | if (tr->trace_buffer.buffer) |
6013 | ring_buffer_free(tr->trace_buffer.buffer); | |
277ba044 SR |
6014 | kfree(tr->name); |
6015 | kfree(tr); | |
6016 | ||
6017 | out_unlock: | |
6018 | mutex_unlock(&trace_types_lock); | |
6019 | ||
6020 | return ret; | |
6021 | ||
6022 | } | |
6023 | ||
0c8916c3 SR |
6024 | static int instance_delete(const char *name) |
6025 | { | |
6026 | struct trace_array *tr; | |
6027 | int found = 0; | |
6028 | int ret; | |
6029 | ||
6030 | mutex_lock(&trace_types_lock); | |
6031 | ||
6032 | ret = -ENODEV; | |
6033 | list_for_each_entry(tr, &ftrace_trace_arrays, list) { | |
6034 | if (tr->name && strcmp(tr->name, name) == 0) { | |
6035 | found = 1; | |
6036 | break; | |
6037 | } | |
6038 | } | |
6039 | if (!found) | |
6040 | goto out_unlock; | |
6041 | ||
a695cb58 SRRH |
6042 | ret = -EBUSY; |
6043 | if (tr->ref) | |
6044 | goto out_unlock; | |
6045 | ||
0c8916c3 SR |
6046 | list_del(&tr->list); |
6047 | ||
6048 | event_trace_del_tracer(tr); | |
6049 | debugfs_remove_recursive(tr->dir); | |
12883efb SRRH |
6050 | free_percpu(tr->trace_buffer.data); |
6051 | ring_buffer_free(tr->trace_buffer.buffer); | |
0c8916c3 SR |
6052 | |
6053 | kfree(tr->name); | |
6054 | kfree(tr); | |
6055 | ||
6056 | ret = 0; | |
6057 | ||
6058 | out_unlock: | |
6059 | mutex_unlock(&trace_types_lock); | |
6060 | ||
6061 | return ret; | |
6062 | } | |
6063 | ||
277ba044 SR |
6064 | static int instance_mkdir (struct inode *inode, struct dentry *dentry, umode_t mode) |
6065 | { | |
6066 | struct dentry *parent; | |
6067 | int ret; | |
6068 | ||
6069 | /* Paranoid: Make sure the parent is the "instances" directory */ | |
6637ecd3 | 6070 | parent = hlist_entry(inode->i_dentry.first, struct dentry, d_u.d_alias); |
277ba044 SR |
6071 | if (WARN_ON_ONCE(parent != trace_instance_dir)) |
6072 | return -ENOENT; | |
6073 | ||
6074 | /* | |
6075 | * The inode mutex is locked, but debugfs_create_dir() will also | |
6076 | * take the mutex. As the instances directory can not be destroyed | |
6077 | * or changed in any other way, it is safe to unlock it, and | |
6078 | * let the dentry try. If two users try to make the same dir at | |
6079 | * the same time, then the new_instance_create() will determine the | |
6080 | * winner. | |
6081 | */ | |
6082 | mutex_unlock(&inode->i_mutex); | |
6083 | ||
6084 | ret = new_instance_create(dentry->d_iname); | |
6085 | ||
6086 | mutex_lock(&inode->i_mutex); | |
6087 | ||
6088 | return ret; | |
6089 | } | |
6090 | ||
0c8916c3 SR |
6091 | static int instance_rmdir(struct inode *inode, struct dentry *dentry) |
6092 | { | |
6093 | struct dentry *parent; | |
6094 | int ret; | |
6095 | ||
6096 | /* Paranoid: Make sure the parent is the "instances" directory */ | |
6637ecd3 | 6097 | parent = hlist_entry(inode->i_dentry.first, struct dentry, d_u.d_alias); |
0c8916c3 SR |
6098 | if (WARN_ON_ONCE(parent != trace_instance_dir)) |
6099 | return -ENOENT; | |
6100 | ||
6101 | /* The caller did a dget() on dentry */ | |
6102 | mutex_unlock(&dentry->d_inode->i_mutex); | |
6103 | ||
6104 | /* | |
6105 | * The inode mutex is locked, but debugfs_create_dir() will also | |
6106 | * take the mutex. As the instances directory can not be destroyed | |
6107 | * or changed in any other way, it is safe to unlock it, and | |
6108 | * let the dentry try. If two users try to make the same dir at | |
6109 | * the same time, then the instance_delete() will determine the | |
6110 | * winner. | |
6111 | */ | |
6112 | mutex_unlock(&inode->i_mutex); | |
6113 | ||
6114 | ret = instance_delete(dentry->d_iname); | |
6115 | ||
6116 | mutex_lock_nested(&inode->i_mutex, I_MUTEX_PARENT); | |
6117 | mutex_lock(&dentry->d_inode->i_mutex); | |
6118 | ||
6119 | return ret; | |
6120 | } | |
6121 | ||
277ba044 SR |
6122 | static const struct inode_operations instance_dir_inode_operations = { |
6123 | .lookup = simple_lookup, | |
6124 | .mkdir = instance_mkdir, | |
0c8916c3 | 6125 | .rmdir = instance_rmdir, |
277ba044 SR |
6126 | }; |
6127 | ||
6128 | static __init void create_trace_instances(struct dentry *d_tracer) | |
6129 | { | |
6130 | trace_instance_dir = debugfs_create_dir("instances", d_tracer); | |
6131 | if (WARN_ON(!trace_instance_dir)) | |
6132 | return; | |
6133 | ||
6134 | /* Hijack the dir inode operations, to allow mkdir */ | |
6135 | trace_instance_dir->d_inode->i_op = &instance_dir_inode_operations; | |
6136 | } | |
6137 | ||
2b6080f2 SR |
6138 | static void |
6139 | init_tracer_debugfs(struct trace_array *tr, struct dentry *d_tracer) | |
6140 | { | |
121aaee7 | 6141 | int cpu; |
2b6080f2 SR |
6142 | |
6143 | trace_create_file("trace_options", 0644, d_tracer, | |
6144 | tr, &tracing_iter_fops); | |
6145 | ||
6146 | trace_create_file("trace", 0644, d_tracer, | |
7272711a | 6147 | tr, &tracing_fops); |
2b6080f2 SR |
6148 | |
6149 | trace_create_file("trace_pipe", 0444, d_tracer, | |
23b625fa | 6150 | tr, &tracing_pipe_fops); |
2b6080f2 SR |
6151 | |
6152 | trace_create_file("buffer_size_kb", 0644, d_tracer, | |
e5dd03c4 | 6153 | tr, &tracing_entries_fops); |
2b6080f2 SR |
6154 | |
6155 | trace_create_file("buffer_total_size_kb", 0444, d_tracer, | |
6156 | tr, &tracing_total_entries_fops); | |
6157 | ||
6158 | trace_create_file("free_buffer", 0644, d_tracer, | |
6159 | tr, &tracing_free_buffer_fops); | |
6160 | ||
6161 | trace_create_file("trace_marker", 0220, d_tracer, | |
6162 | tr, &tracing_mark_fops); | |
6163 | ||
6164 | trace_create_file("trace_clock", 0644, d_tracer, tr, | |
6165 | &trace_clock_fops); | |
6166 | ||
6167 | trace_create_file("tracing_on", 0644, d_tracer, | |
7272711a | 6168 | tr, &rb_simple_fops); |
ce9bae55 SRRH |
6169 | |
6170 | #ifdef CONFIG_TRACER_SNAPSHOT | |
6171 | trace_create_file("snapshot", 0644, d_tracer, | |
7272711a | 6172 | tr, &snapshot_fops); |
ce9bae55 | 6173 | #endif |
121aaee7 SRRH |
6174 | |
6175 | for_each_tracing_cpu(cpu) | |
6176 | tracing_init_debugfs_percpu(tr, cpu); | |
6177 | ||
2b6080f2 SR |
6178 | } |
6179 | ||
b5ad384e | 6180 | static __init int tracer_init_debugfs(void) |
bc0c38d1 SR |
6181 | { |
6182 | struct dentry *d_tracer; | |
bc0c38d1 | 6183 | |
7e53bd42 LJ |
6184 | trace_access_lock_init(); |
6185 | ||
bc0c38d1 | 6186 | d_tracer = tracing_init_dentry(); |
ed6f1c99 NK |
6187 | if (!d_tracer) |
6188 | return 0; | |
bc0c38d1 | 6189 | |
2b6080f2 | 6190 | init_tracer_debugfs(&global_trace, d_tracer); |
bc0c38d1 | 6191 | |
5452af66 | 6192 | trace_create_file("tracing_cpumask", 0644, d_tracer, |
2b6080f2 | 6193 | &global_trace, &tracing_cpumask_fops); |
a8259075 | 6194 | |
5452af66 FW |
6195 | trace_create_file("available_tracers", 0444, d_tracer, |
6196 | &global_trace, &show_traces_fops); | |
6197 | ||
339ae5d3 | 6198 | trace_create_file("current_tracer", 0644, d_tracer, |
5452af66 FW |
6199 | &global_trace, &set_tracer_fops); |
6200 | ||
5d4a9dba | 6201 | #ifdef CONFIG_TRACER_MAX_TRACE |
5452af66 FW |
6202 | trace_create_file("tracing_max_latency", 0644, d_tracer, |
6203 | &tracing_max_latency, &tracing_max_lat_fops); | |
0e950173 | 6204 | #endif |
5452af66 FW |
6205 | |
6206 | trace_create_file("tracing_thresh", 0644, d_tracer, | |
6207 | &tracing_thresh, &tracing_max_lat_fops); | |
a8259075 | 6208 | |
339ae5d3 | 6209 | trace_create_file("README", 0444, d_tracer, |
5452af66 FW |
6210 | NULL, &tracing_readme_fops); |
6211 | ||
69abe6a5 AP |
6212 | trace_create_file("saved_cmdlines", 0444, d_tracer, |
6213 | NULL, &tracing_saved_cmdlines_fops); | |
5bf9a1ee | 6214 | |
bc0c38d1 | 6215 | #ifdef CONFIG_DYNAMIC_FTRACE |
5452af66 FW |
6216 | trace_create_file("dyn_ftrace_total_info", 0444, d_tracer, |
6217 | &ftrace_update_tot_cnt, &tracing_dyn_info_fops); | |
bc0c38d1 | 6218 | #endif |
b04cc6b1 | 6219 | |
277ba044 | 6220 | create_trace_instances(d_tracer); |
5452af66 | 6221 | |
2b6080f2 | 6222 | create_trace_options_dir(&global_trace); |
b04cc6b1 | 6223 | |
b5ad384e | 6224 | return 0; |
bc0c38d1 SR |
6225 | } |
6226 | ||
3f5a54e3 SR |
6227 | static int trace_panic_handler(struct notifier_block *this, |
6228 | unsigned long event, void *unused) | |
6229 | { | |
944ac425 | 6230 | if (ftrace_dump_on_oops) |
cecbca96 | 6231 | ftrace_dump(ftrace_dump_on_oops); |
3f5a54e3 SR |
6232 | return NOTIFY_OK; |
6233 | } | |
6234 | ||
6235 | static struct notifier_block trace_panic_notifier = { | |
6236 | .notifier_call = trace_panic_handler, | |
6237 | .next = NULL, | |
6238 | .priority = 150 /* priority: INT_MAX >= x >= 0 */ | |
6239 | }; | |
6240 | ||
6241 | static int trace_die_handler(struct notifier_block *self, | |
6242 | unsigned long val, | |
6243 | void *data) | |
6244 | { | |
6245 | switch (val) { | |
6246 | case DIE_OOPS: | |
944ac425 | 6247 | if (ftrace_dump_on_oops) |
cecbca96 | 6248 | ftrace_dump(ftrace_dump_on_oops); |
3f5a54e3 SR |
6249 | break; |
6250 | default: | |
6251 | break; | |
6252 | } | |
6253 | return NOTIFY_OK; | |
6254 | } | |
6255 | ||
6256 | static struct notifier_block trace_die_notifier = { | |
6257 | .notifier_call = trace_die_handler, | |
6258 | .priority = 200 | |
6259 | }; | |
6260 | ||
6261 | /* | |
6262 | * printk is set to max of 1024, we really don't need it that big. | |
6263 | * Nothing should be printing 1000 characters anyway. | |
6264 | */ | |
6265 | #define TRACE_MAX_PRINT 1000 | |
6266 | ||
6267 | /* | |
6268 | * Define here KERN_TRACE so that we have one place to modify | |
6269 | * it if we decide to change what log level the ftrace dump | |
6270 | * should be at. | |
6271 | */ | |
428aee14 | 6272 | #define KERN_TRACE KERN_EMERG |
3f5a54e3 | 6273 | |
955b61e5 | 6274 | void |
3f5a54e3 SR |
6275 | trace_printk_seq(struct trace_seq *s) |
6276 | { | |
6277 | /* Probably should print a warning here. */ | |
bd6df187 J |
6278 | if (s->len >= TRACE_MAX_PRINT) |
6279 | s->len = TRACE_MAX_PRINT; | |
3f5a54e3 SR |
6280 | |
6281 | /* should be zero ended, but we are paranoid. */ | |
6282 | s->buffer[s->len] = 0; | |
6283 | ||
6284 | printk(KERN_TRACE "%s", s->buffer); | |
6285 | ||
f9520750 | 6286 | trace_seq_init(s); |
3f5a54e3 SR |
6287 | } |
6288 | ||
955b61e5 JW |
6289 | void trace_init_global_iter(struct trace_iterator *iter) |
6290 | { | |
6291 | iter->tr = &global_trace; | |
2b6080f2 | 6292 | iter->trace = iter->tr->current_trace; |
ae3b5093 | 6293 | iter->cpu_file = RING_BUFFER_ALL_CPUS; |
12883efb | 6294 | iter->trace_buffer = &global_trace.trace_buffer; |
955b61e5 JW |
6295 | } |
6296 | ||
7fe70b57 | 6297 | void ftrace_dump(enum ftrace_dump_mode oops_dump_mode) |
3f5a54e3 | 6298 | { |
3f5a54e3 SR |
6299 | /* use static because iter can be a bit big for the stack */ |
6300 | static struct trace_iterator iter; | |
7fe70b57 | 6301 | static atomic_t dump_running; |
cf586b61 | 6302 | unsigned int old_userobj; |
d769041f SR |
6303 | unsigned long flags; |
6304 | int cnt = 0, cpu; | |
3f5a54e3 | 6305 | |
7fe70b57 SRRH |
6306 | /* Only allow one dump user at a time. */ |
6307 | if (atomic_inc_return(&dump_running) != 1) { | |
6308 | atomic_dec(&dump_running); | |
6309 | return; | |
6310 | } | |
3f5a54e3 | 6311 | |
7fe70b57 SRRH |
6312 | /* |
6313 | * Always turn off tracing when we dump. | |
6314 | * We don't need to show trace output of what happens | |
6315 | * between multiple crashes. | |
6316 | * | |
6317 | * If the user does a sysrq-z, then they can re-enable | |
6318 | * tracing with echo 1 > tracing_on. | |
6319 | */ | |
0ee6b6cf | 6320 | tracing_off(); |
cf586b61 | 6321 | |
7fe70b57 | 6322 | local_irq_save(flags); |
3f5a54e3 | 6323 | |
38dbe0b1 | 6324 | /* Simulate the iterator */ |
955b61e5 JW |
6325 | trace_init_global_iter(&iter); |
6326 | ||
d769041f | 6327 | for_each_tracing_cpu(cpu) { |
12883efb | 6328 | atomic_inc(&per_cpu_ptr(iter.tr->trace_buffer.data, cpu)->disabled); |
d769041f SR |
6329 | } |
6330 | ||
cf586b61 FW |
6331 | old_userobj = trace_flags & TRACE_ITER_SYM_USEROBJ; |
6332 | ||
b54d3de9 TE |
6333 | /* don't look at user memory in panic mode */ |
6334 | trace_flags &= ~TRACE_ITER_SYM_USEROBJ; | |
6335 | ||
cecbca96 FW |
6336 | switch (oops_dump_mode) { |
6337 | case DUMP_ALL: | |
ae3b5093 | 6338 | iter.cpu_file = RING_BUFFER_ALL_CPUS; |
cecbca96 FW |
6339 | break; |
6340 | case DUMP_ORIG: | |
6341 | iter.cpu_file = raw_smp_processor_id(); | |
6342 | break; | |
6343 | case DUMP_NONE: | |
6344 | goto out_enable; | |
6345 | default: | |
6346 | printk(KERN_TRACE "Bad dumping mode, switching to all CPUs dump\n"); | |
ae3b5093 | 6347 | iter.cpu_file = RING_BUFFER_ALL_CPUS; |
cecbca96 FW |
6348 | } |
6349 | ||
6350 | printk(KERN_TRACE "Dumping ftrace buffer:\n"); | |
3f5a54e3 | 6351 | |
7fe70b57 SRRH |
6352 | /* Did function tracer already get disabled? */ |
6353 | if (ftrace_is_dead()) { | |
6354 | printk("# WARNING: FUNCTION TRACING IS CORRUPTED\n"); | |
6355 | printk("# MAY BE MISSING FUNCTION EVENTS\n"); | |
6356 | } | |
6357 | ||
3f5a54e3 SR |
6358 | /* |
6359 | * We need to stop all tracing on all CPUS to read the | |
6360 | * the next buffer. This is a bit expensive, but is | |
6361 | * not done often. We fill all what we can read, | |
6362 | * and then release the locks again. | |
6363 | */ | |
6364 | ||
3f5a54e3 SR |
6365 | while (!trace_empty(&iter)) { |
6366 | ||
6367 | if (!cnt) | |
6368 | printk(KERN_TRACE "---------------------------------\n"); | |
6369 | ||
6370 | cnt++; | |
6371 | ||
6372 | /* reset all but tr, trace, and overruns */ | |
6373 | memset(&iter.seq, 0, | |
6374 | sizeof(struct trace_iterator) - | |
6375 | offsetof(struct trace_iterator, seq)); | |
6376 | iter.iter_flags |= TRACE_FILE_LAT_FMT; | |
6377 | iter.pos = -1; | |
6378 | ||
955b61e5 | 6379 | if (trace_find_next_entry_inc(&iter) != NULL) { |
74e7ff8c LJ |
6380 | int ret; |
6381 | ||
6382 | ret = print_trace_line(&iter); | |
6383 | if (ret != TRACE_TYPE_NO_CONSUME) | |
6384 | trace_consume(&iter); | |
3f5a54e3 | 6385 | } |
b892e5c8 | 6386 | touch_nmi_watchdog(); |
3f5a54e3 SR |
6387 | |
6388 | trace_printk_seq(&iter.seq); | |
6389 | } | |
6390 | ||
6391 | if (!cnt) | |
6392 | printk(KERN_TRACE " (ftrace buffer empty)\n"); | |
6393 | else | |
6394 | printk(KERN_TRACE "---------------------------------\n"); | |
6395 | ||
cecbca96 | 6396 | out_enable: |
7fe70b57 | 6397 | trace_flags |= old_userobj; |
cf586b61 | 6398 | |
7fe70b57 SRRH |
6399 | for_each_tracing_cpu(cpu) { |
6400 | atomic_dec(&per_cpu_ptr(iter.trace_buffer->data, cpu)->disabled); | |
cf586b61 | 6401 | } |
7fe70b57 | 6402 | atomic_dec(&dump_running); |
cd891ae0 | 6403 | local_irq_restore(flags); |
3f5a54e3 | 6404 | } |
a8eecf22 | 6405 | EXPORT_SYMBOL_GPL(ftrace_dump); |
cf586b61 | 6406 | |
3928a8a2 | 6407 | __init static int tracer_alloc_buffers(void) |
bc0c38d1 | 6408 | { |
73c5162a | 6409 | int ring_buf_size; |
9e01c1b7 | 6410 | int ret = -ENOMEM; |
4c11d7ae | 6411 | |
750912fa | 6412 | |
9e01c1b7 RR |
6413 | if (!alloc_cpumask_var(&tracing_buffer_mask, GFP_KERNEL)) |
6414 | goto out; | |
6415 | ||
6416 | if (!alloc_cpumask_var(&tracing_cpumask, GFP_KERNEL)) | |
6417 | goto out_free_buffer_mask; | |
4c11d7ae | 6418 | |
07d777fe SR |
6419 | /* Only allocate trace_printk buffers if a trace_printk exists */ |
6420 | if (__stop___trace_bprintk_fmt != __start___trace_bprintk_fmt) | |
81698831 | 6421 | /* Must be called before global_trace.buffer is allocated */ |
07d777fe SR |
6422 | trace_printk_init_buffers(); |
6423 | ||
73c5162a SR |
6424 | /* To save memory, keep the ring buffer size to its minimum */ |
6425 | if (ring_buffer_expanded) | |
6426 | ring_buf_size = trace_buf_size; | |
6427 | else | |
6428 | ring_buf_size = 1; | |
6429 | ||
9e01c1b7 RR |
6430 | cpumask_copy(tracing_buffer_mask, cpu_possible_mask); |
6431 | cpumask_copy(tracing_cpumask, cpu_all_mask); | |
6432 | ||
2b6080f2 SR |
6433 | raw_spin_lock_init(&global_trace.start_lock); |
6434 | ||
9e01c1b7 | 6435 | /* TODO: make the number of buffers hot pluggable with CPUS */ |
737223fb | 6436 | if (allocate_trace_buffers(&global_trace, ring_buf_size) < 0) { |
3928a8a2 SR |
6437 | printk(KERN_ERR "tracer: failed to allocate ring buffer!\n"); |
6438 | WARN_ON(1); | |
9e01c1b7 | 6439 | goto out_free_cpumask; |
4c11d7ae | 6440 | } |
a7603ff4 | 6441 | |
499e5470 SR |
6442 | if (global_trace.buffer_disabled) |
6443 | tracing_off(); | |
4c11d7ae | 6444 | |
bc0c38d1 SR |
6445 | trace_init_cmdlines(); |
6446 | ||
ca164318 SRRH |
6447 | /* |
6448 | * register_tracer() might reference current_trace, so it | |
6449 | * needs to be set before we register anything. This is | |
6450 | * just a bootstrap of current_trace anyway. | |
6451 | */ | |
2b6080f2 SR |
6452 | global_trace.current_trace = &nop_trace; |
6453 | ||
ca164318 SRRH |
6454 | register_tracer(&nop_trace); |
6455 | ||
60a11774 SR |
6456 | /* All seems OK, enable tracing */ |
6457 | tracing_disabled = 0; | |
3928a8a2 | 6458 | |
3f5a54e3 SR |
6459 | atomic_notifier_chain_register(&panic_notifier_list, |
6460 | &trace_panic_notifier); | |
6461 | ||
6462 | register_die_notifier(&trace_die_notifier); | |
2fc1dfbe | 6463 | |
ae63b31e SR |
6464 | global_trace.flags = TRACE_ARRAY_FL_GLOBAL; |
6465 | ||
2b6080f2 SR |
6466 | /* Holder for file callbacks */ |
6467 | global_trace.trace_cpu.cpu = RING_BUFFER_ALL_CPUS; | |
6468 | global_trace.trace_cpu.tr = &global_trace; | |
6469 | ||
ae63b31e SR |
6470 | INIT_LIST_HEAD(&global_trace.systems); |
6471 | INIT_LIST_HEAD(&global_trace.events); | |
6472 | list_add(&global_trace.list, &ftrace_trace_arrays); | |
6473 | ||
7bcfaf54 SR |
6474 | while (trace_boot_options) { |
6475 | char *option; | |
6476 | ||
6477 | option = strsep(&trace_boot_options, ","); | |
2b6080f2 | 6478 | trace_set_options(&global_trace, option); |
7bcfaf54 SR |
6479 | } |
6480 | ||
77fd5c15 SRRH |
6481 | register_snapshot_cmd(); |
6482 | ||
2fc1dfbe | 6483 | return 0; |
3f5a54e3 | 6484 | |
9e01c1b7 | 6485 | out_free_cpumask: |
12883efb SRRH |
6486 | free_percpu(global_trace.trace_buffer.data); |
6487 | #ifdef CONFIG_TRACER_MAX_TRACE | |
6488 | free_percpu(global_trace.max_buffer.data); | |
6489 | #endif | |
9e01c1b7 RR |
6490 | free_cpumask_var(tracing_cpumask); |
6491 | out_free_buffer_mask: | |
6492 | free_cpumask_var(tracing_buffer_mask); | |
6493 | out: | |
6494 | return ret; | |
bc0c38d1 | 6495 | } |
b2821ae6 SR |
6496 | |
6497 | __init static int clear_boot_tracer(void) | |
6498 | { | |
6499 | /* | |
6500 | * The default tracer at boot buffer is an init section. | |
6501 | * This function is called in lateinit. If we did not | |
6502 | * find the boot tracer, then clear it out, to prevent | |
6503 | * later registration from accessing the buffer that is | |
6504 | * about to be freed. | |
6505 | */ | |
6506 | if (!default_bootup_tracer) | |
6507 | return 0; | |
6508 | ||
6509 | printk(KERN_INFO "ftrace bootup tracer '%s' not registered.\n", | |
6510 | default_bootup_tracer); | |
6511 | default_bootup_tracer = NULL; | |
6512 | ||
6513 | return 0; | |
6514 | } | |
6515 | ||
b5ad384e FW |
6516 | early_initcall(tracer_alloc_buffers); |
6517 | fs_initcall(tracer_init_debugfs); | |
b2821ae6 | 6518 | late_initcall(clear_boot_tracer); |