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 | ||
8c1a49ae SRRH |
76 | static int |
77 | dummy_set_flag(struct trace_array *tr, u32 old_flags, u32 bit, int set) | |
adf9f195 FW |
78 | { |
79 | return 0; | |
80 | } | |
0f048701 | 81 | |
7ffbd48d SR |
82 | /* |
83 | * To prevent the comm cache from being overwritten when no | |
84 | * tracing is active, only save the comm when a trace event | |
85 | * occurred. | |
86 | */ | |
87 | static DEFINE_PER_CPU(bool, trace_cmdline_save); | |
88 | ||
0f048701 SR |
89 | /* |
90 | * Kill all tracing for good (never come back). | |
91 | * It is initialized to 1 but will turn to zero if the initialization | |
92 | * of the tracer is successful. But that is the only place that sets | |
93 | * this back to zero. | |
94 | */ | |
4fd27358 | 95 | static int tracing_disabled = 1; |
0f048701 | 96 | |
9288f99a | 97 | DEFINE_PER_CPU(int, ftrace_cpu_disabled); |
d769041f | 98 | |
955b61e5 | 99 | cpumask_var_t __read_mostly tracing_buffer_mask; |
ab46428c | 100 | |
944ac425 SR |
101 | /* |
102 | * ftrace_dump_on_oops - variable to dump ftrace buffer on oops | |
103 | * | |
104 | * If there is an oops (or kernel panic) and the ftrace_dump_on_oops | |
105 | * is set, then ftrace_dump is called. This will output the contents | |
106 | * of the ftrace buffers to the console. This is very useful for | |
107 | * capturing traces that lead to crashes and outputing it to a | |
108 | * serial console. | |
109 | * | |
110 | * It is default off, but you can enable it with either specifying | |
111 | * "ftrace_dump_on_oops" in the kernel command line, or setting | |
cecbca96 FW |
112 | * /proc/sys/kernel/ftrace_dump_on_oops |
113 | * Set 1 if you want to dump buffers of all CPUs | |
114 | * Set 2 if you want to dump the buffer of the CPU that triggered oops | |
944ac425 | 115 | */ |
cecbca96 FW |
116 | |
117 | enum ftrace_dump_mode ftrace_dump_on_oops; | |
944ac425 | 118 | |
de7edd31 SRRH |
119 | /* When set, tracing will stop when a WARN*() is hit */ |
120 | int __disable_trace_on_warning; | |
121 | ||
607e2ea1 | 122 | static int tracing_set_tracer(struct trace_array *tr, const char *buf); |
b2821ae6 | 123 | |
ee6c2c1b LZ |
124 | #define MAX_TRACER_SIZE 100 |
125 | static char bootup_tracer_buf[MAX_TRACER_SIZE] __initdata; | |
b2821ae6 | 126 | static char *default_bootup_tracer; |
d9e54076 | 127 | |
55034cd6 SRRH |
128 | static bool allocate_snapshot; |
129 | ||
1beee96b | 130 | static int __init set_cmdline_ftrace(char *str) |
d9e54076 | 131 | { |
67012ab1 | 132 | strlcpy(bootup_tracer_buf, str, MAX_TRACER_SIZE); |
b2821ae6 | 133 | default_bootup_tracer = bootup_tracer_buf; |
73c5162a | 134 | /* We are using ftrace early, expand it */ |
55034cd6 | 135 | ring_buffer_expanded = true; |
d9e54076 PZ |
136 | return 1; |
137 | } | |
1beee96b | 138 | __setup("ftrace=", set_cmdline_ftrace); |
d9e54076 | 139 | |
944ac425 SR |
140 | static int __init set_ftrace_dump_on_oops(char *str) |
141 | { | |
cecbca96 FW |
142 | if (*str++ != '=' || !*str) { |
143 | ftrace_dump_on_oops = DUMP_ALL; | |
144 | return 1; | |
145 | } | |
146 | ||
147 | if (!strcmp("orig_cpu", str)) { | |
148 | ftrace_dump_on_oops = DUMP_ORIG; | |
149 | return 1; | |
150 | } | |
151 | ||
152 | return 0; | |
944ac425 SR |
153 | } |
154 | __setup("ftrace_dump_on_oops", set_ftrace_dump_on_oops); | |
60a11774 | 155 | |
de7edd31 SRRH |
156 | static int __init stop_trace_on_warning(char *str) |
157 | { | |
158 | __disable_trace_on_warning = 1; | |
159 | return 1; | |
160 | } | |
161 | __setup("traceoff_on_warning=", stop_trace_on_warning); | |
162 | ||
3209cff4 | 163 | static int __init boot_alloc_snapshot(char *str) |
55034cd6 SRRH |
164 | { |
165 | allocate_snapshot = true; | |
166 | /* We also need the main ring buffer expanded */ | |
167 | ring_buffer_expanded = true; | |
168 | return 1; | |
169 | } | |
3209cff4 | 170 | __setup("alloc_snapshot", boot_alloc_snapshot); |
55034cd6 | 171 | |
7bcfaf54 SR |
172 | |
173 | static char trace_boot_options_buf[MAX_TRACER_SIZE] __initdata; | |
174 | static char *trace_boot_options __initdata; | |
175 | ||
176 | static int __init set_trace_boot_options(char *str) | |
177 | { | |
67012ab1 | 178 | strlcpy(trace_boot_options_buf, str, MAX_TRACER_SIZE); |
7bcfaf54 SR |
179 | trace_boot_options = trace_boot_options_buf; |
180 | return 0; | |
181 | } | |
182 | __setup("trace_options=", set_trace_boot_options); | |
183 | ||
e1e232ca SR |
184 | static char trace_boot_clock_buf[MAX_TRACER_SIZE] __initdata; |
185 | static char *trace_boot_clock __initdata; | |
186 | ||
187 | static int __init set_trace_boot_clock(char *str) | |
188 | { | |
189 | strlcpy(trace_boot_clock_buf, str, MAX_TRACER_SIZE); | |
190 | trace_boot_clock = trace_boot_clock_buf; | |
191 | return 0; | |
192 | } | |
193 | __setup("trace_clock=", set_trace_boot_clock); | |
194 | ||
de7edd31 | 195 | |
cf8e3474 | 196 | unsigned long long ns2usecs(cycle_t nsec) |
bc0c38d1 SR |
197 | { |
198 | nsec += 500; | |
199 | do_div(nsec, 1000); | |
200 | return nsec; | |
201 | } | |
202 | ||
4fcdae83 SR |
203 | /* |
204 | * The global_trace is the descriptor that holds the tracing | |
205 | * buffers for the live tracing. For each CPU, it contains | |
206 | * a link list of pages that will store trace entries. The | |
207 | * page descriptor of the pages in the memory is used to hold | |
208 | * the link list by linking the lru item in the page descriptor | |
209 | * to each of the pages in the buffer per CPU. | |
210 | * | |
211 | * For each active CPU there is a data field that holds the | |
212 | * pages for the buffer for that CPU. Each CPU has the same number | |
213 | * of pages allocated for its buffer. | |
214 | */ | |
bc0c38d1 SR |
215 | static struct trace_array global_trace; |
216 | ||
ae63b31e | 217 | LIST_HEAD(ftrace_trace_arrays); |
bc0c38d1 | 218 | |
ff451961 SRRH |
219 | int trace_array_get(struct trace_array *this_tr) |
220 | { | |
221 | struct trace_array *tr; | |
222 | int ret = -ENODEV; | |
223 | ||
224 | mutex_lock(&trace_types_lock); | |
225 | list_for_each_entry(tr, &ftrace_trace_arrays, list) { | |
226 | if (tr == this_tr) { | |
227 | tr->ref++; | |
228 | ret = 0; | |
229 | break; | |
230 | } | |
231 | } | |
232 | mutex_unlock(&trace_types_lock); | |
233 | ||
234 | return ret; | |
235 | } | |
236 | ||
237 | static void __trace_array_put(struct trace_array *this_tr) | |
238 | { | |
239 | WARN_ON(!this_tr->ref); | |
240 | this_tr->ref--; | |
241 | } | |
242 | ||
243 | void trace_array_put(struct trace_array *this_tr) | |
244 | { | |
245 | mutex_lock(&trace_types_lock); | |
246 | __trace_array_put(this_tr); | |
247 | mutex_unlock(&trace_types_lock); | |
248 | } | |
249 | ||
f306cc82 TZ |
250 | int filter_check_discard(struct ftrace_event_file *file, void *rec, |
251 | struct ring_buffer *buffer, | |
252 | struct ring_buffer_event *event) | |
eb02ce01 | 253 | { |
f306cc82 TZ |
254 | if (unlikely(file->flags & FTRACE_EVENT_FL_FILTERED) && |
255 | !filter_match_preds(file->filter, rec)) { | |
256 | ring_buffer_discard_commit(buffer, event); | |
257 | return 1; | |
258 | } | |
259 | ||
260 | return 0; | |
261 | } | |
262 | EXPORT_SYMBOL_GPL(filter_check_discard); | |
263 | ||
264 | int call_filter_check_discard(struct ftrace_event_call *call, void *rec, | |
265 | struct ring_buffer *buffer, | |
266 | struct ring_buffer_event *event) | |
267 | { | |
268 | if (unlikely(call->flags & TRACE_EVENT_FL_FILTERED) && | |
269 | !filter_match_preds(call->filter, rec)) { | |
270 | ring_buffer_discard_commit(buffer, event); | |
271 | return 1; | |
272 | } | |
273 | ||
274 | return 0; | |
eb02ce01 | 275 | } |
f306cc82 | 276 | EXPORT_SYMBOL_GPL(call_filter_check_discard); |
eb02ce01 | 277 | |
ad1438a0 | 278 | static cycle_t buffer_ftrace_now(struct trace_buffer *buf, int cpu) |
37886f6a SR |
279 | { |
280 | u64 ts; | |
281 | ||
282 | /* Early boot up does not have a buffer yet */ | |
9457158b | 283 | if (!buf->buffer) |
37886f6a SR |
284 | return trace_clock_local(); |
285 | ||
9457158b AL |
286 | ts = ring_buffer_time_stamp(buf->buffer, cpu); |
287 | ring_buffer_normalize_time_stamp(buf->buffer, cpu, &ts); | |
37886f6a SR |
288 | |
289 | return ts; | |
290 | } | |
bc0c38d1 | 291 | |
9457158b AL |
292 | cycle_t ftrace_now(int cpu) |
293 | { | |
294 | return buffer_ftrace_now(&global_trace.trace_buffer, cpu); | |
295 | } | |
296 | ||
10246fa3 SRRH |
297 | /** |
298 | * tracing_is_enabled - Show if global_trace has been disabled | |
299 | * | |
300 | * Shows if the global trace has been enabled or not. It uses the | |
301 | * mirror flag "buffer_disabled" to be used in fast paths such as for | |
302 | * the irqsoff tracer. But it may be inaccurate due to races. If you | |
303 | * need to know the accurate state, use tracing_is_on() which is a little | |
304 | * slower, but accurate. | |
305 | */ | |
9036990d SR |
306 | int tracing_is_enabled(void) |
307 | { | |
10246fa3 SRRH |
308 | /* |
309 | * For quick access (irqsoff uses this in fast path), just | |
310 | * return the mirror variable of the state of the ring buffer. | |
311 | * It's a little racy, but we don't really care. | |
312 | */ | |
313 | smp_rmb(); | |
314 | return !global_trace.buffer_disabled; | |
9036990d SR |
315 | } |
316 | ||
4fcdae83 | 317 | /* |
3928a8a2 SR |
318 | * trace_buf_size is the size in bytes that is allocated |
319 | * for a buffer. Note, the number of bytes is always rounded | |
320 | * to page size. | |
3f5a54e3 SR |
321 | * |
322 | * This number is purposely set to a low number of 16384. | |
323 | * If the dump on oops happens, it will be much appreciated | |
324 | * to not have to wait for all that output. Anyway this can be | |
325 | * boot time and run time configurable. | |
4fcdae83 | 326 | */ |
3928a8a2 | 327 | #define TRACE_BUF_SIZE_DEFAULT 1441792UL /* 16384 * 88 (sizeof(entry)) */ |
3f5a54e3 | 328 | |
3928a8a2 | 329 | static unsigned long trace_buf_size = TRACE_BUF_SIZE_DEFAULT; |
bc0c38d1 | 330 | |
4fcdae83 | 331 | /* trace_types holds a link list of available tracers. */ |
bc0c38d1 | 332 | static struct tracer *trace_types __read_mostly; |
4fcdae83 | 333 | |
4fcdae83 SR |
334 | /* |
335 | * trace_types_lock is used to protect the trace_types list. | |
4fcdae83 | 336 | */ |
a8227415 | 337 | DEFINE_MUTEX(trace_types_lock); |
4fcdae83 | 338 | |
7e53bd42 LJ |
339 | /* |
340 | * serialize the access of the ring buffer | |
341 | * | |
342 | * ring buffer serializes readers, but it is low level protection. | |
343 | * The validity of the events (which returns by ring_buffer_peek() ..etc) | |
344 | * are not protected by ring buffer. | |
345 | * | |
346 | * The content of events may become garbage if we allow other process consumes | |
347 | * these events concurrently: | |
348 | * A) the page of the consumed events may become a normal page | |
349 | * (not reader page) in ring buffer, and this page will be rewrited | |
350 | * by events producer. | |
351 | * B) The page of the consumed events may become a page for splice_read, | |
352 | * and this page will be returned to system. | |
353 | * | |
354 | * These primitives allow multi process access to different cpu ring buffer | |
355 | * concurrently. | |
356 | * | |
357 | * These primitives don't distinguish read-only and read-consume access. | |
358 | * Multi read-only access are also serialized. | |
359 | */ | |
360 | ||
361 | #ifdef CONFIG_SMP | |
362 | static DECLARE_RWSEM(all_cpu_access_lock); | |
363 | static DEFINE_PER_CPU(struct mutex, cpu_access_lock); | |
364 | ||
365 | static inline void trace_access_lock(int cpu) | |
366 | { | |
ae3b5093 | 367 | if (cpu == RING_BUFFER_ALL_CPUS) { |
7e53bd42 LJ |
368 | /* gain it for accessing the whole ring buffer. */ |
369 | down_write(&all_cpu_access_lock); | |
370 | } else { | |
371 | /* gain it for accessing a cpu ring buffer. */ | |
372 | ||
ae3b5093 | 373 | /* Firstly block other trace_access_lock(RING_BUFFER_ALL_CPUS). */ |
7e53bd42 LJ |
374 | down_read(&all_cpu_access_lock); |
375 | ||
376 | /* Secondly block other access to this @cpu ring buffer. */ | |
377 | mutex_lock(&per_cpu(cpu_access_lock, cpu)); | |
378 | } | |
379 | } | |
380 | ||
381 | static inline void trace_access_unlock(int cpu) | |
382 | { | |
ae3b5093 | 383 | if (cpu == RING_BUFFER_ALL_CPUS) { |
7e53bd42 LJ |
384 | up_write(&all_cpu_access_lock); |
385 | } else { | |
386 | mutex_unlock(&per_cpu(cpu_access_lock, cpu)); | |
387 | up_read(&all_cpu_access_lock); | |
388 | } | |
389 | } | |
390 | ||
391 | static inline void trace_access_lock_init(void) | |
392 | { | |
393 | int cpu; | |
394 | ||
395 | for_each_possible_cpu(cpu) | |
396 | mutex_init(&per_cpu(cpu_access_lock, cpu)); | |
397 | } | |
398 | ||
399 | #else | |
400 | ||
401 | static DEFINE_MUTEX(access_lock); | |
402 | ||
403 | static inline void trace_access_lock(int cpu) | |
404 | { | |
405 | (void)cpu; | |
406 | mutex_lock(&access_lock); | |
407 | } | |
408 | ||
409 | static inline void trace_access_unlock(int cpu) | |
410 | { | |
411 | (void)cpu; | |
412 | mutex_unlock(&access_lock); | |
413 | } | |
414 | ||
415 | static inline void trace_access_lock_init(void) | |
416 | { | |
417 | } | |
418 | ||
419 | #endif | |
420 | ||
ee6bce52 | 421 | /* trace_flags holds trace_options default values */ |
12ef7d44 | 422 | unsigned long trace_flags = TRACE_ITER_PRINT_PARENT | TRACE_ITER_PRINTK | |
a2a16d6a | 423 | TRACE_ITER_ANNOTATE | TRACE_ITER_CONTEXT_INFO | TRACE_ITER_SLEEP_TIME | |
77271ce4 | 424 | TRACE_ITER_GRAPH_TIME | TRACE_ITER_RECORD_CMD | TRACE_ITER_OVERWRITE | |
328df475 | 425 | TRACE_ITER_IRQ_INFO | TRACE_ITER_MARKERS | TRACE_ITER_FUNCTION; |
e7e2ee89 | 426 | |
5280bcef | 427 | static void tracer_tracing_on(struct trace_array *tr) |
10246fa3 SRRH |
428 | { |
429 | if (tr->trace_buffer.buffer) | |
430 | ring_buffer_record_on(tr->trace_buffer.buffer); | |
431 | /* | |
432 | * This flag is looked at when buffers haven't been allocated | |
433 | * yet, or by some tracers (like irqsoff), that just want to | |
434 | * know if the ring buffer has been disabled, but it can handle | |
435 | * races of where it gets disabled but we still do a record. | |
436 | * As the check is in the fast path of the tracers, it is more | |
437 | * important to be fast than accurate. | |
438 | */ | |
439 | tr->buffer_disabled = 0; | |
440 | /* Make the flag seen by readers */ | |
441 | smp_wmb(); | |
442 | } | |
443 | ||
499e5470 SR |
444 | /** |
445 | * tracing_on - enable tracing buffers | |
446 | * | |
447 | * This function enables tracing buffers that may have been | |
448 | * disabled with tracing_off. | |
449 | */ | |
450 | void tracing_on(void) | |
451 | { | |
10246fa3 | 452 | tracer_tracing_on(&global_trace); |
499e5470 SR |
453 | } |
454 | EXPORT_SYMBOL_GPL(tracing_on); | |
455 | ||
09ae7234 SRRH |
456 | /** |
457 | * __trace_puts - write a constant string into the trace buffer. | |
458 | * @ip: The address of the caller | |
459 | * @str: The constant string to write | |
460 | * @size: The size of the string. | |
461 | */ | |
462 | int __trace_puts(unsigned long ip, const char *str, int size) | |
463 | { | |
464 | struct ring_buffer_event *event; | |
465 | struct ring_buffer *buffer; | |
466 | struct print_entry *entry; | |
467 | unsigned long irq_flags; | |
468 | int alloc; | |
469 | ||
3132e107 SRRH |
470 | if (unlikely(tracing_selftest_running || tracing_disabled)) |
471 | return 0; | |
472 | ||
09ae7234 SRRH |
473 | alloc = sizeof(*entry) + size + 2; /* possible \n added */ |
474 | ||
475 | local_save_flags(irq_flags); | |
476 | buffer = global_trace.trace_buffer.buffer; | |
477 | event = trace_buffer_lock_reserve(buffer, TRACE_PRINT, alloc, | |
478 | irq_flags, preempt_count()); | |
479 | if (!event) | |
480 | return 0; | |
481 | ||
482 | entry = ring_buffer_event_data(event); | |
483 | entry->ip = ip; | |
484 | ||
485 | memcpy(&entry->buf, str, size); | |
486 | ||
487 | /* Add a newline if necessary */ | |
488 | if (entry->buf[size - 1] != '\n') { | |
489 | entry->buf[size] = '\n'; | |
490 | entry->buf[size + 1] = '\0'; | |
491 | } else | |
492 | entry->buf[size] = '\0'; | |
493 | ||
494 | __buffer_unlock_commit(buffer, event); | |
495 | ||
496 | return size; | |
497 | } | |
498 | EXPORT_SYMBOL_GPL(__trace_puts); | |
499 | ||
500 | /** | |
501 | * __trace_bputs - write the pointer to a constant string into trace buffer | |
502 | * @ip: The address of the caller | |
503 | * @str: The constant string to write to the buffer to | |
504 | */ | |
505 | int __trace_bputs(unsigned long ip, const char *str) | |
506 | { | |
507 | struct ring_buffer_event *event; | |
508 | struct ring_buffer *buffer; | |
509 | struct bputs_entry *entry; | |
510 | unsigned long irq_flags; | |
511 | int size = sizeof(struct bputs_entry); | |
512 | ||
3132e107 SRRH |
513 | if (unlikely(tracing_selftest_running || tracing_disabled)) |
514 | return 0; | |
515 | ||
09ae7234 SRRH |
516 | local_save_flags(irq_flags); |
517 | buffer = global_trace.trace_buffer.buffer; | |
518 | event = trace_buffer_lock_reserve(buffer, TRACE_BPUTS, size, | |
519 | irq_flags, preempt_count()); | |
520 | if (!event) | |
521 | return 0; | |
522 | ||
523 | entry = ring_buffer_event_data(event); | |
524 | entry->ip = ip; | |
525 | entry->str = str; | |
526 | ||
527 | __buffer_unlock_commit(buffer, event); | |
528 | ||
529 | return 1; | |
530 | } | |
531 | EXPORT_SYMBOL_GPL(__trace_bputs); | |
532 | ||
ad909e21 SRRH |
533 | #ifdef CONFIG_TRACER_SNAPSHOT |
534 | /** | |
535 | * trace_snapshot - take a snapshot of the current buffer. | |
536 | * | |
537 | * This causes a swap between the snapshot buffer and the current live | |
538 | * tracing buffer. You can use this to take snapshots of the live | |
539 | * trace when some condition is triggered, but continue to trace. | |
540 | * | |
541 | * Note, make sure to allocate the snapshot with either | |
542 | * a tracing_snapshot_alloc(), or by doing it manually | |
543 | * with: echo 1 > /sys/kernel/debug/tracing/snapshot | |
544 | * | |
545 | * If the snapshot buffer is not allocated, it will stop tracing. | |
546 | * Basically making a permanent snapshot. | |
547 | */ | |
548 | void tracing_snapshot(void) | |
549 | { | |
550 | struct trace_array *tr = &global_trace; | |
551 | struct tracer *tracer = tr->current_trace; | |
552 | unsigned long flags; | |
553 | ||
1b22e382 SRRH |
554 | if (in_nmi()) { |
555 | internal_trace_puts("*** SNAPSHOT CALLED FROM NMI CONTEXT ***\n"); | |
556 | internal_trace_puts("*** snapshot is being ignored ***\n"); | |
557 | return; | |
558 | } | |
559 | ||
ad909e21 | 560 | if (!tr->allocated_snapshot) { |
ca268da6 SRRH |
561 | internal_trace_puts("*** SNAPSHOT NOT ALLOCATED ***\n"); |
562 | internal_trace_puts("*** stopping trace here! ***\n"); | |
ad909e21 SRRH |
563 | tracing_off(); |
564 | return; | |
565 | } | |
566 | ||
567 | /* Note, snapshot can not be used when the tracer uses it */ | |
568 | if (tracer->use_max_tr) { | |
ca268da6 SRRH |
569 | internal_trace_puts("*** LATENCY TRACER ACTIVE ***\n"); |
570 | internal_trace_puts("*** Can not use snapshot (sorry) ***\n"); | |
ad909e21 SRRH |
571 | return; |
572 | } | |
573 | ||
574 | local_irq_save(flags); | |
575 | update_max_tr(tr, current, smp_processor_id()); | |
576 | local_irq_restore(flags); | |
577 | } | |
1b22e382 | 578 | EXPORT_SYMBOL_GPL(tracing_snapshot); |
ad909e21 SRRH |
579 | |
580 | static int resize_buffer_duplicate_size(struct trace_buffer *trace_buf, | |
581 | struct trace_buffer *size_buf, int cpu_id); | |
3209cff4 SRRH |
582 | static void set_buffer_entries(struct trace_buffer *buf, unsigned long val); |
583 | ||
584 | static int alloc_snapshot(struct trace_array *tr) | |
585 | { | |
586 | int ret; | |
587 | ||
588 | if (!tr->allocated_snapshot) { | |
589 | ||
590 | /* allocate spare buffer */ | |
591 | ret = resize_buffer_duplicate_size(&tr->max_buffer, | |
592 | &tr->trace_buffer, RING_BUFFER_ALL_CPUS); | |
593 | if (ret < 0) | |
594 | return ret; | |
595 | ||
596 | tr->allocated_snapshot = true; | |
597 | } | |
598 | ||
599 | return 0; | |
600 | } | |
601 | ||
ad1438a0 | 602 | static void free_snapshot(struct trace_array *tr) |
3209cff4 SRRH |
603 | { |
604 | /* | |
605 | * We don't free the ring buffer. instead, resize it because | |
606 | * The max_tr ring buffer has some state (e.g. ring->clock) and | |
607 | * we want preserve it. | |
608 | */ | |
609 | ring_buffer_resize(tr->max_buffer.buffer, 1, RING_BUFFER_ALL_CPUS); | |
610 | set_buffer_entries(&tr->max_buffer, 1); | |
611 | tracing_reset_online_cpus(&tr->max_buffer); | |
612 | tr->allocated_snapshot = false; | |
613 | } | |
ad909e21 | 614 | |
93e31ffb TZ |
615 | /** |
616 | * tracing_alloc_snapshot - allocate snapshot buffer. | |
617 | * | |
618 | * This only allocates the snapshot buffer if it isn't already | |
619 | * allocated - it doesn't also take a snapshot. | |
620 | * | |
621 | * This is meant to be used in cases where the snapshot buffer needs | |
622 | * to be set up for events that can't sleep but need to be able to | |
623 | * trigger a snapshot. | |
624 | */ | |
625 | int tracing_alloc_snapshot(void) | |
626 | { | |
627 | struct trace_array *tr = &global_trace; | |
628 | int ret; | |
629 | ||
630 | ret = alloc_snapshot(tr); | |
631 | WARN_ON(ret < 0); | |
632 | ||
633 | return ret; | |
634 | } | |
635 | EXPORT_SYMBOL_GPL(tracing_alloc_snapshot); | |
636 | ||
ad909e21 SRRH |
637 | /** |
638 | * trace_snapshot_alloc - allocate and take a snapshot of the current buffer. | |
639 | * | |
640 | * This is similar to trace_snapshot(), but it will allocate the | |
641 | * snapshot buffer if it isn't already allocated. Use this only | |
642 | * where it is safe to sleep, as the allocation may sleep. | |
643 | * | |
644 | * This causes a swap between the snapshot buffer and the current live | |
645 | * tracing buffer. You can use this to take snapshots of the live | |
646 | * trace when some condition is triggered, but continue to trace. | |
647 | */ | |
648 | void tracing_snapshot_alloc(void) | |
649 | { | |
ad909e21 SRRH |
650 | int ret; |
651 | ||
93e31ffb TZ |
652 | ret = tracing_alloc_snapshot(); |
653 | if (ret < 0) | |
3209cff4 | 654 | return; |
ad909e21 SRRH |
655 | |
656 | tracing_snapshot(); | |
657 | } | |
1b22e382 | 658 | EXPORT_SYMBOL_GPL(tracing_snapshot_alloc); |
ad909e21 SRRH |
659 | #else |
660 | void tracing_snapshot(void) | |
661 | { | |
662 | WARN_ONCE(1, "Snapshot feature not enabled, but internal snapshot used"); | |
663 | } | |
1b22e382 | 664 | EXPORT_SYMBOL_GPL(tracing_snapshot); |
93e31ffb TZ |
665 | int tracing_alloc_snapshot(void) |
666 | { | |
667 | WARN_ONCE(1, "Snapshot feature not enabled, but snapshot allocation used"); | |
668 | return -ENODEV; | |
669 | } | |
670 | EXPORT_SYMBOL_GPL(tracing_alloc_snapshot); | |
ad909e21 SRRH |
671 | void tracing_snapshot_alloc(void) |
672 | { | |
673 | /* Give warning */ | |
674 | tracing_snapshot(); | |
675 | } | |
1b22e382 | 676 | EXPORT_SYMBOL_GPL(tracing_snapshot_alloc); |
ad909e21 SRRH |
677 | #endif /* CONFIG_TRACER_SNAPSHOT */ |
678 | ||
5280bcef | 679 | static void tracer_tracing_off(struct trace_array *tr) |
10246fa3 SRRH |
680 | { |
681 | if (tr->trace_buffer.buffer) | |
682 | ring_buffer_record_off(tr->trace_buffer.buffer); | |
683 | /* | |
684 | * This flag is looked at when buffers haven't been allocated | |
685 | * yet, or by some tracers (like irqsoff), that just want to | |
686 | * know if the ring buffer has been disabled, but it can handle | |
687 | * races of where it gets disabled but we still do a record. | |
688 | * As the check is in the fast path of the tracers, it is more | |
689 | * important to be fast than accurate. | |
690 | */ | |
691 | tr->buffer_disabled = 1; | |
692 | /* Make the flag seen by readers */ | |
693 | smp_wmb(); | |
694 | } | |
695 | ||
499e5470 SR |
696 | /** |
697 | * tracing_off - turn off tracing buffers | |
698 | * | |
699 | * This function stops the tracing buffers from recording data. | |
700 | * It does not disable any overhead the tracers themselves may | |
701 | * be causing. This function simply causes all recording to | |
702 | * the ring buffers to fail. | |
703 | */ | |
704 | void tracing_off(void) | |
705 | { | |
10246fa3 | 706 | tracer_tracing_off(&global_trace); |
499e5470 SR |
707 | } |
708 | EXPORT_SYMBOL_GPL(tracing_off); | |
709 | ||
de7edd31 SRRH |
710 | void disable_trace_on_warning(void) |
711 | { | |
712 | if (__disable_trace_on_warning) | |
713 | tracing_off(); | |
714 | } | |
715 | ||
10246fa3 SRRH |
716 | /** |
717 | * tracer_tracing_is_on - show real state of ring buffer enabled | |
718 | * @tr : the trace array to know if ring buffer is enabled | |
719 | * | |
720 | * Shows real state of the ring buffer if it is enabled or not. | |
721 | */ | |
5280bcef | 722 | static int tracer_tracing_is_on(struct trace_array *tr) |
10246fa3 SRRH |
723 | { |
724 | if (tr->trace_buffer.buffer) | |
725 | return ring_buffer_record_is_on(tr->trace_buffer.buffer); | |
726 | return !tr->buffer_disabled; | |
727 | } | |
728 | ||
499e5470 SR |
729 | /** |
730 | * tracing_is_on - show state of ring buffers enabled | |
731 | */ | |
732 | int tracing_is_on(void) | |
733 | { | |
10246fa3 | 734 | return tracer_tracing_is_on(&global_trace); |
499e5470 SR |
735 | } |
736 | EXPORT_SYMBOL_GPL(tracing_is_on); | |
737 | ||
3928a8a2 | 738 | static int __init set_buf_size(char *str) |
bc0c38d1 | 739 | { |
3928a8a2 | 740 | unsigned long buf_size; |
c6caeeb1 | 741 | |
bc0c38d1 SR |
742 | if (!str) |
743 | return 0; | |
9d612bef | 744 | buf_size = memparse(str, &str); |
c6caeeb1 | 745 | /* nr_entries can not be zero */ |
9d612bef | 746 | if (buf_size == 0) |
c6caeeb1 | 747 | return 0; |
3928a8a2 | 748 | trace_buf_size = buf_size; |
bc0c38d1 SR |
749 | return 1; |
750 | } | |
3928a8a2 | 751 | __setup("trace_buf_size=", set_buf_size); |
bc0c38d1 | 752 | |
0e950173 TB |
753 | static int __init set_tracing_thresh(char *str) |
754 | { | |
87abb3b1 | 755 | unsigned long threshold; |
0e950173 TB |
756 | int ret; |
757 | ||
758 | if (!str) | |
759 | return 0; | |
bcd83ea6 | 760 | ret = kstrtoul(str, 0, &threshold); |
0e950173 TB |
761 | if (ret < 0) |
762 | return 0; | |
87abb3b1 | 763 | tracing_thresh = threshold * 1000; |
0e950173 TB |
764 | return 1; |
765 | } | |
766 | __setup("tracing_thresh=", set_tracing_thresh); | |
767 | ||
57f50be1 SR |
768 | unsigned long nsecs_to_usecs(unsigned long nsecs) |
769 | { | |
770 | return nsecs / 1000; | |
771 | } | |
772 | ||
4fcdae83 | 773 | /* These must match the bit postions in trace_iterator_flags */ |
bc0c38d1 SR |
774 | static const char *trace_options[] = { |
775 | "print-parent", | |
776 | "sym-offset", | |
777 | "sym-addr", | |
778 | "verbose", | |
f9896bf3 | 779 | "raw", |
5e3ca0ec | 780 | "hex", |
cb0f12aa | 781 | "bin", |
2a2cc8f7 | 782 | "block", |
86387f7e | 783 | "stacktrace", |
5e1607a0 | 784 | "trace_printk", |
b2a866f9 | 785 | "ftrace_preempt", |
9f029e83 | 786 | "branch", |
12ef7d44 | 787 | "annotate", |
02b67518 | 788 | "userstacktrace", |
b54d3de9 | 789 | "sym-userobj", |
66896a85 | 790 | "printk-msg-only", |
c4a8e8be | 791 | "context-info", |
c032ef64 | 792 | "latency-format", |
be6f164a | 793 | "sleep-time", |
a2a16d6a | 794 | "graph-time", |
e870e9a1 | 795 | "record-cmd", |
750912fa | 796 | "overwrite", |
cf30cf67 | 797 | "disable_on_free", |
77271ce4 | 798 | "irq-info", |
5224c3a3 | 799 | "markers", |
328df475 | 800 | "function-trace", |
bc0c38d1 SR |
801 | NULL |
802 | }; | |
803 | ||
5079f326 Z |
804 | static struct { |
805 | u64 (*func)(void); | |
806 | const char *name; | |
8be0709f | 807 | int in_ns; /* is this clock in nanoseconds? */ |
5079f326 | 808 | } trace_clocks[] = { |
8be0709f DS |
809 | { trace_clock_local, "local", 1 }, |
810 | { trace_clock_global, "global", 1 }, | |
811 | { trace_clock_counter, "counter", 0 }, | |
8aacf017 | 812 | { trace_clock_jiffies, "uptime", 1 }, |
76f11917 | 813 | { trace_clock, "perf", 1 }, |
8cbd9cc6 | 814 | ARCH_TRACE_CLOCKS |
5079f326 Z |
815 | }; |
816 | ||
b63f39ea | 817 | /* |
818 | * trace_parser_get_init - gets the buffer for trace parser | |
819 | */ | |
820 | int trace_parser_get_init(struct trace_parser *parser, int size) | |
821 | { | |
822 | memset(parser, 0, sizeof(*parser)); | |
823 | ||
824 | parser->buffer = kmalloc(size, GFP_KERNEL); | |
825 | if (!parser->buffer) | |
826 | return 1; | |
827 | ||
828 | parser->size = size; | |
829 | return 0; | |
830 | } | |
831 | ||
832 | /* | |
833 | * trace_parser_put - frees the buffer for trace parser | |
834 | */ | |
835 | void trace_parser_put(struct trace_parser *parser) | |
836 | { | |
837 | kfree(parser->buffer); | |
838 | } | |
839 | ||
840 | /* | |
841 | * trace_get_user - reads the user input string separated by space | |
842 | * (matched by isspace(ch)) | |
843 | * | |
844 | * For each string found the 'struct trace_parser' is updated, | |
845 | * and the function returns. | |
846 | * | |
847 | * Returns number of bytes read. | |
848 | * | |
849 | * See kernel/trace/trace.h for 'struct trace_parser' details. | |
850 | */ | |
851 | int trace_get_user(struct trace_parser *parser, const char __user *ubuf, | |
852 | size_t cnt, loff_t *ppos) | |
853 | { | |
854 | char ch; | |
855 | size_t read = 0; | |
856 | ssize_t ret; | |
857 | ||
858 | if (!*ppos) | |
859 | trace_parser_clear(parser); | |
860 | ||
861 | ret = get_user(ch, ubuf++); | |
862 | if (ret) | |
863 | goto out; | |
864 | ||
865 | read++; | |
866 | cnt--; | |
867 | ||
868 | /* | |
869 | * The parser is not finished with the last write, | |
870 | * continue reading the user input without skipping spaces. | |
871 | */ | |
872 | if (!parser->cont) { | |
873 | /* skip white space */ | |
874 | while (cnt && isspace(ch)) { | |
875 | ret = get_user(ch, ubuf++); | |
876 | if (ret) | |
877 | goto out; | |
878 | read++; | |
879 | cnt--; | |
880 | } | |
881 | ||
882 | /* only spaces were written */ | |
883 | if (isspace(ch)) { | |
884 | *ppos += read; | |
885 | ret = read; | |
886 | goto out; | |
887 | } | |
888 | ||
889 | parser->idx = 0; | |
890 | } | |
891 | ||
892 | /* read the non-space input */ | |
893 | while (cnt && !isspace(ch)) { | |
3c235a33 | 894 | if (parser->idx < parser->size - 1) |
b63f39ea | 895 | parser->buffer[parser->idx++] = ch; |
896 | else { | |
897 | ret = -EINVAL; | |
898 | goto out; | |
899 | } | |
900 | ret = get_user(ch, ubuf++); | |
901 | if (ret) | |
902 | goto out; | |
903 | read++; | |
904 | cnt--; | |
905 | } | |
906 | ||
907 | /* We either got finished input or we have to wait for another call. */ | |
908 | if (isspace(ch)) { | |
909 | parser->buffer[parser->idx] = 0; | |
910 | parser->cont = false; | |
057db848 | 911 | } else if (parser->idx < parser->size - 1) { |
b63f39ea | 912 | parser->cont = true; |
913 | parser->buffer[parser->idx++] = ch; | |
057db848 SR |
914 | } else { |
915 | ret = -EINVAL; | |
916 | goto out; | |
b63f39ea | 917 | } |
918 | ||
919 | *ppos += read; | |
920 | ret = read; | |
921 | ||
922 | out: | |
923 | return ret; | |
924 | } | |
925 | ||
6c6c2796 PP |
926 | ssize_t trace_seq_to_user(struct trace_seq *s, char __user *ubuf, size_t cnt) |
927 | { | |
928 | int len; | |
929 | int ret; | |
930 | ||
2dc5d12b SR |
931 | if (!cnt) |
932 | return 0; | |
933 | ||
6c6c2796 PP |
934 | if (s->len <= s->readpos) |
935 | return -EBUSY; | |
936 | ||
937 | len = s->len - s->readpos; | |
938 | if (cnt > len) | |
939 | cnt = len; | |
940 | ret = copy_to_user(ubuf, s->buffer + s->readpos, cnt); | |
2dc5d12b | 941 | if (ret == cnt) |
6c6c2796 PP |
942 | return -EFAULT; |
943 | ||
2dc5d12b SR |
944 | cnt -= ret; |
945 | ||
e74da523 | 946 | s->readpos += cnt; |
6c6c2796 | 947 | return cnt; |
214023c3 SR |
948 | } |
949 | ||
b8b94265 | 950 | static ssize_t trace_seq_to_buffer(struct trace_seq *s, void *buf, size_t cnt) |
3c56819b EGM |
951 | { |
952 | int len; | |
3c56819b EGM |
953 | |
954 | if (s->len <= s->readpos) | |
955 | return -EBUSY; | |
956 | ||
957 | len = s->len - s->readpos; | |
958 | if (cnt > len) | |
959 | cnt = len; | |
5a26c8f0 | 960 | memcpy(buf, s->buffer + s->readpos, cnt); |
3c56819b | 961 | |
e74da523 | 962 | s->readpos += cnt; |
3c56819b EGM |
963 | return cnt; |
964 | } | |
965 | ||
0e950173 TB |
966 | unsigned long __read_mostly tracing_thresh; |
967 | ||
5d4a9dba | 968 | #ifdef CONFIG_TRACER_MAX_TRACE |
5d4a9dba SR |
969 | /* |
970 | * Copy the new maximum trace into the separate maximum-trace | |
971 | * structure. (this way the maximum trace is permanently saved, | |
972 | * for later retrieval via /sys/kernel/debug/tracing/latency_trace) | |
973 | */ | |
974 | static void | |
975 | __update_max_tr(struct trace_array *tr, struct task_struct *tsk, int cpu) | |
976 | { | |
12883efb SRRH |
977 | struct trace_buffer *trace_buf = &tr->trace_buffer; |
978 | struct trace_buffer *max_buf = &tr->max_buffer; | |
979 | struct trace_array_cpu *data = per_cpu_ptr(trace_buf->data, cpu); | |
980 | struct trace_array_cpu *max_data = per_cpu_ptr(max_buf->data, cpu); | |
5d4a9dba | 981 | |
12883efb SRRH |
982 | max_buf->cpu = cpu; |
983 | max_buf->time_start = data->preempt_timestamp; | |
5d4a9dba | 984 | |
6d9b3fa5 | 985 | max_data->saved_latency = tr->max_latency; |
8248ac05 SR |
986 | max_data->critical_start = data->critical_start; |
987 | max_data->critical_end = data->critical_end; | |
5d4a9dba | 988 | |
1acaa1b2 | 989 | memcpy(max_data->comm, tsk->comm, TASK_COMM_LEN); |
8248ac05 | 990 | max_data->pid = tsk->pid; |
f17a5194 SRRH |
991 | /* |
992 | * If tsk == current, then use current_uid(), as that does not use | |
993 | * RCU. The irq tracer can be called out of RCU scope. | |
994 | */ | |
995 | if (tsk == current) | |
996 | max_data->uid = current_uid(); | |
997 | else | |
998 | max_data->uid = task_uid(tsk); | |
999 | ||
8248ac05 SR |
1000 | max_data->nice = tsk->static_prio - 20 - MAX_RT_PRIO; |
1001 | max_data->policy = tsk->policy; | |
1002 | max_data->rt_priority = tsk->rt_priority; | |
5d4a9dba SR |
1003 | |
1004 | /* record this tasks comm */ | |
1005 | tracing_record_cmdline(tsk); | |
1006 | } | |
1007 | ||
4fcdae83 SR |
1008 | /** |
1009 | * update_max_tr - snapshot all trace buffers from global_trace to max_tr | |
1010 | * @tr: tracer | |
1011 | * @tsk: the task with the latency | |
1012 | * @cpu: The cpu that initiated the trace. | |
1013 | * | |
1014 | * Flip the buffers between the @tr and the max_tr and record information | |
1015 | * about which task was the cause of this latency. | |
1016 | */ | |
e309b41d | 1017 | void |
bc0c38d1 SR |
1018 | update_max_tr(struct trace_array *tr, struct task_struct *tsk, int cpu) |
1019 | { | |
2721e72d | 1020 | struct ring_buffer *buf; |
bc0c38d1 | 1021 | |
2b6080f2 | 1022 | if (tr->stop_count) |
b8de7bd1 SR |
1023 | return; |
1024 | ||
4c11d7ae | 1025 | WARN_ON_ONCE(!irqs_disabled()); |
34600f0e | 1026 | |
45ad21ca | 1027 | if (!tr->allocated_snapshot) { |
debdd57f | 1028 | /* Only the nop tracer should hit this when disabling */ |
2b6080f2 | 1029 | WARN_ON_ONCE(tr->current_trace != &nop_trace); |
34600f0e | 1030 | return; |
debdd57f | 1031 | } |
34600f0e | 1032 | |
0b9b12c1 | 1033 | arch_spin_lock(&tr->max_lock); |
3928a8a2 | 1034 | |
12883efb SRRH |
1035 | buf = tr->trace_buffer.buffer; |
1036 | tr->trace_buffer.buffer = tr->max_buffer.buffer; | |
1037 | tr->max_buffer.buffer = buf; | |
3928a8a2 | 1038 | |
bc0c38d1 | 1039 | __update_max_tr(tr, tsk, cpu); |
0b9b12c1 | 1040 | arch_spin_unlock(&tr->max_lock); |
bc0c38d1 SR |
1041 | } |
1042 | ||
1043 | /** | |
1044 | * update_max_tr_single - only copy one trace over, and reset the rest | |
1045 | * @tr - tracer | |
1046 | * @tsk - task with the latency | |
1047 | * @cpu - the cpu of the buffer to copy. | |
4fcdae83 SR |
1048 | * |
1049 | * Flip the trace of a single CPU buffer between the @tr and the max_tr. | |
bc0c38d1 | 1050 | */ |
e309b41d | 1051 | void |
bc0c38d1 SR |
1052 | update_max_tr_single(struct trace_array *tr, struct task_struct *tsk, int cpu) |
1053 | { | |
3928a8a2 | 1054 | int ret; |
bc0c38d1 | 1055 | |
2b6080f2 | 1056 | if (tr->stop_count) |
b8de7bd1 SR |
1057 | return; |
1058 | ||
4c11d7ae | 1059 | WARN_ON_ONCE(!irqs_disabled()); |
6c24499f | 1060 | if (!tr->allocated_snapshot) { |
2930e04d | 1061 | /* Only the nop tracer should hit this when disabling */ |
9e8529af | 1062 | WARN_ON_ONCE(tr->current_trace != &nop_trace); |
ef710e10 | 1063 | return; |
2930e04d | 1064 | } |
ef710e10 | 1065 | |
0b9b12c1 | 1066 | arch_spin_lock(&tr->max_lock); |
bc0c38d1 | 1067 | |
12883efb | 1068 | ret = ring_buffer_swap_cpu(tr->max_buffer.buffer, tr->trace_buffer.buffer, cpu); |
3928a8a2 | 1069 | |
e8165dbb SR |
1070 | if (ret == -EBUSY) { |
1071 | /* | |
1072 | * We failed to swap the buffer due to a commit taking | |
1073 | * place on this CPU. We fail to record, but we reset | |
1074 | * the max trace buffer (no one writes directly to it) | |
1075 | * and flag that it failed. | |
1076 | */ | |
12883efb | 1077 | trace_array_printk_buf(tr->max_buffer.buffer, _THIS_IP_, |
e8165dbb SR |
1078 | "Failed to swap buffers due to commit in progress\n"); |
1079 | } | |
1080 | ||
e8165dbb | 1081 | WARN_ON_ONCE(ret && ret != -EAGAIN && ret != -EBUSY); |
bc0c38d1 SR |
1082 | |
1083 | __update_max_tr(tr, tsk, cpu); | |
0b9b12c1 | 1084 | arch_spin_unlock(&tr->max_lock); |
bc0c38d1 | 1085 | } |
5d4a9dba | 1086 | #endif /* CONFIG_TRACER_MAX_TRACE */ |
bc0c38d1 | 1087 | |
b1169cc6 | 1088 | static void wait_on_pipe(struct trace_iterator *iter) |
0d5c6e1c | 1089 | { |
15693458 SRRH |
1090 | /* Iterators are static, they should be filled or empty */ |
1091 | if (trace_buffer_iter(iter, iter->cpu_file)) | |
1092 | return; | |
0d5c6e1c | 1093 | |
12883efb | 1094 | ring_buffer_wait(iter->trace_buffer->buffer, iter->cpu_file); |
0d5c6e1c SR |
1095 | } |
1096 | ||
f4e781c0 SRRH |
1097 | #ifdef CONFIG_FTRACE_STARTUP_TEST |
1098 | static int run_tracer_selftest(struct tracer *type) | |
1099 | { | |
1100 | struct trace_array *tr = &global_trace; | |
1101 | struct tracer *saved_tracer = tr->current_trace; | |
1102 | int ret; | |
0d5c6e1c | 1103 | |
f4e781c0 SRRH |
1104 | if (!type->selftest || tracing_selftest_disabled) |
1105 | return 0; | |
0d5c6e1c SR |
1106 | |
1107 | /* | |
f4e781c0 SRRH |
1108 | * Run a selftest on this tracer. |
1109 | * Here we reset the trace buffer, and set the current | |
1110 | * tracer to be this tracer. The tracer can then run some | |
1111 | * internal tracing to verify that everything is in order. | |
1112 | * If we fail, we do not register this tracer. | |
0d5c6e1c | 1113 | */ |
f4e781c0 | 1114 | tracing_reset_online_cpus(&tr->trace_buffer); |
0d5c6e1c | 1115 | |
f4e781c0 SRRH |
1116 | tr->current_trace = type; |
1117 | ||
1118 | #ifdef CONFIG_TRACER_MAX_TRACE | |
1119 | if (type->use_max_tr) { | |
1120 | /* If we expanded the buffers, make sure the max is expanded too */ | |
1121 | if (ring_buffer_expanded) | |
1122 | ring_buffer_resize(tr->max_buffer.buffer, trace_buf_size, | |
1123 | RING_BUFFER_ALL_CPUS); | |
1124 | tr->allocated_snapshot = true; | |
1125 | } | |
1126 | #endif | |
1127 | ||
1128 | /* the test is responsible for initializing and enabling */ | |
1129 | pr_info("Testing tracer %s: ", type->name); | |
1130 | ret = type->selftest(type, tr); | |
1131 | /* the test is responsible for resetting too */ | |
1132 | tr->current_trace = saved_tracer; | |
1133 | if (ret) { | |
1134 | printk(KERN_CONT "FAILED!\n"); | |
1135 | /* Add the warning after printing 'FAILED' */ | |
1136 | WARN_ON(1); | |
1137 | return -1; | |
1138 | } | |
1139 | /* Only reset on passing, to avoid touching corrupted buffers */ | |
1140 | tracing_reset_online_cpus(&tr->trace_buffer); | |
1141 | ||
1142 | #ifdef CONFIG_TRACER_MAX_TRACE | |
1143 | if (type->use_max_tr) { | |
1144 | tr->allocated_snapshot = false; | |
0d5c6e1c | 1145 | |
f4e781c0 SRRH |
1146 | /* Shrink the max buffer again */ |
1147 | if (ring_buffer_expanded) | |
1148 | ring_buffer_resize(tr->max_buffer.buffer, 1, | |
1149 | RING_BUFFER_ALL_CPUS); | |
1150 | } | |
1151 | #endif | |
1152 | ||
1153 | printk(KERN_CONT "PASSED\n"); | |
1154 | return 0; | |
1155 | } | |
1156 | #else | |
1157 | static inline int run_tracer_selftest(struct tracer *type) | |
1158 | { | |
1159 | return 0; | |
0d5c6e1c | 1160 | } |
f4e781c0 | 1161 | #endif /* CONFIG_FTRACE_STARTUP_TEST */ |
0d5c6e1c | 1162 | |
4fcdae83 SR |
1163 | /** |
1164 | * register_tracer - register a tracer with the ftrace system. | |
1165 | * @type - the plugin for the tracer | |
1166 | * | |
1167 | * Register a new plugin tracer. | |
1168 | */ | |
bc0c38d1 SR |
1169 | int register_tracer(struct tracer *type) |
1170 | { | |
1171 | struct tracer *t; | |
bc0c38d1 SR |
1172 | int ret = 0; |
1173 | ||
1174 | if (!type->name) { | |
1175 | pr_info("Tracer must have a name\n"); | |
1176 | return -1; | |
1177 | } | |
1178 | ||
24a461d5 | 1179 | if (strlen(type->name) >= MAX_TRACER_SIZE) { |
ee6c2c1b LZ |
1180 | pr_info("Tracer has a name longer than %d\n", MAX_TRACER_SIZE); |
1181 | return -1; | |
1182 | } | |
1183 | ||
bc0c38d1 | 1184 | mutex_lock(&trace_types_lock); |
86fa2f60 | 1185 | |
8e1b82e0 FW |
1186 | tracing_selftest_running = true; |
1187 | ||
bc0c38d1 SR |
1188 | for (t = trace_types; t; t = t->next) { |
1189 | if (strcmp(type->name, t->name) == 0) { | |
1190 | /* already found */ | |
ee6c2c1b | 1191 | pr_info("Tracer %s already registered\n", |
bc0c38d1 SR |
1192 | type->name); |
1193 | ret = -1; | |
1194 | goto out; | |
1195 | } | |
1196 | } | |
1197 | ||
adf9f195 FW |
1198 | if (!type->set_flag) |
1199 | type->set_flag = &dummy_set_flag; | |
1200 | if (!type->flags) | |
1201 | type->flags = &dummy_tracer_flags; | |
1202 | else | |
1203 | if (!type->flags->opts) | |
1204 | type->flags->opts = dummy_tracer_opt; | |
6eaaa5d5 | 1205 | |
f4e781c0 SRRH |
1206 | ret = run_tracer_selftest(type); |
1207 | if (ret < 0) | |
1208 | goto out; | |
60a11774 | 1209 | |
bc0c38d1 SR |
1210 | type->next = trace_types; |
1211 | trace_types = type; | |
60a11774 | 1212 | |
bc0c38d1 | 1213 | out: |
8e1b82e0 | 1214 | tracing_selftest_running = false; |
bc0c38d1 SR |
1215 | mutex_unlock(&trace_types_lock); |
1216 | ||
dac74940 SR |
1217 | if (ret || !default_bootup_tracer) |
1218 | goto out_unlock; | |
1219 | ||
ee6c2c1b | 1220 | if (strncmp(default_bootup_tracer, type->name, MAX_TRACER_SIZE)) |
dac74940 SR |
1221 | goto out_unlock; |
1222 | ||
1223 | printk(KERN_INFO "Starting tracer '%s'\n", type->name); | |
1224 | /* Do we want this tracer to start on bootup? */ | |
607e2ea1 | 1225 | tracing_set_tracer(&global_trace, type->name); |
dac74940 SR |
1226 | default_bootup_tracer = NULL; |
1227 | /* disable other selftests, since this will break it. */ | |
55034cd6 | 1228 | tracing_selftest_disabled = true; |
b2821ae6 | 1229 | #ifdef CONFIG_FTRACE_STARTUP_TEST |
dac74940 SR |
1230 | printk(KERN_INFO "Disabling FTRACE selftests due to running tracer '%s'\n", |
1231 | type->name); | |
b2821ae6 | 1232 | #endif |
b2821ae6 | 1233 | |
dac74940 | 1234 | out_unlock: |
bc0c38d1 SR |
1235 | return ret; |
1236 | } | |
1237 | ||
12883efb | 1238 | void tracing_reset(struct trace_buffer *buf, int cpu) |
f633903a | 1239 | { |
12883efb | 1240 | struct ring_buffer *buffer = buf->buffer; |
f633903a | 1241 | |
a5416411 HT |
1242 | if (!buffer) |
1243 | return; | |
1244 | ||
f633903a SR |
1245 | ring_buffer_record_disable(buffer); |
1246 | ||
1247 | /* Make sure all commits have finished */ | |
1248 | synchronize_sched(); | |
68179686 | 1249 | ring_buffer_reset_cpu(buffer, cpu); |
f633903a SR |
1250 | |
1251 | ring_buffer_record_enable(buffer); | |
1252 | } | |
1253 | ||
12883efb | 1254 | void tracing_reset_online_cpus(struct trace_buffer *buf) |
213cc060 | 1255 | { |
12883efb | 1256 | struct ring_buffer *buffer = buf->buffer; |
213cc060 PE |
1257 | int cpu; |
1258 | ||
a5416411 HT |
1259 | if (!buffer) |
1260 | return; | |
1261 | ||
621968cd SR |
1262 | ring_buffer_record_disable(buffer); |
1263 | ||
1264 | /* Make sure all commits have finished */ | |
1265 | synchronize_sched(); | |
1266 | ||
9457158b | 1267 | buf->time_start = buffer_ftrace_now(buf, buf->cpu); |
213cc060 PE |
1268 | |
1269 | for_each_online_cpu(cpu) | |
68179686 | 1270 | ring_buffer_reset_cpu(buffer, cpu); |
621968cd SR |
1271 | |
1272 | ring_buffer_record_enable(buffer); | |
213cc060 PE |
1273 | } |
1274 | ||
09d8091c | 1275 | /* Must have trace_types_lock held */ |
873c642f | 1276 | void tracing_reset_all_online_cpus(void) |
9456f0fa | 1277 | { |
873c642f SRRH |
1278 | struct trace_array *tr; |
1279 | ||
873c642f | 1280 | list_for_each_entry(tr, &ftrace_trace_arrays, list) { |
12883efb SRRH |
1281 | tracing_reset_online_cpus(&tr->trace_buffer); |
1282 | #ifdef CONFIG_TRACER_MAX_TRACE | |
1283 | tracing_reset_online_cpus(&tr->max_buffer); | |
1284 | #endif | |
873c642f | 1285 | } |
9456f0fa SR |
1286 | } |
1287 | ||
bc0c38d1 | 1288 | #define SAVED_CMDLINES 128 |
2c7eea4c | 1289 | #define NO_CMDLINE_MAP UINT_MAX |
bc0c38d1 SR |
1290 | static unsigned map_pid_to_cmdline[PID_MAX_DEFAULT+1]; |
1291 | static unsigned map_cmdline_to_pid[SAVED_CMDLINES]; | |
1292 | static char saved_cmdlines[SAVED_CMDLINES][TASK_COMM_LEN]; | |
1293 | static int cmdline_idx; | |
edc35bd7 | 1294 | static arch_spinlock_t trace_cmdline_lock = __ARCH_SPIN_LOCK_UNLOCKED; |
25b0b44a | 1295 | |
25b0b44a | 1296 | /* temporary disable recording */ |
4fd27358 | 1297 | static atomic_t trace_record_cmdline_disabled __read_mostly; |
bc0c38d1 SR |
1298 | |
1299 | static void trace_init_cmdlines(void) | |
1300 | { | |
2c7eea4c TG |
1301 | memset(&map_pid_to_cmdline, NO_CMDLINE_MAP, sizeof(map_pid_to_cmdline)); |
1302 | memset(&map_cmdline_to_pid, NO_CMDLINE_MAP, sizeof(map_cmdline_to_pid)); | |
bc0c38d1 SR |
1303 | cmdline_idx = 0; |
1304 | } | |
1305 | ||
b5130b1e CE |
1306 | int is_tracing_stopped(void) |
1307 | { | |
2b6080f2 | 1308 | return global_trace.stop_count; |
b5130b1e CE |
1309 | } |
1310 | ||
0f048701 SR |
1311 | /** |
1312 | * tracing_start - quick start of the tracer | |
1313 | * | |
1314 | * If tracing is enabled but was stopped by tracing_stop, | |
1315 | * this will start the tracer back up. | |
1316 | */ | |
1317 | void tracing_start(void) | |
1318 | { | |
1319 | struct ring_buffer *buffer; | |
1320 | unsigned long flags; | |
1321 | ||
1322 | if (tracing_disabled) | |
1323 | return; | |
1324 | ||
2b6080f2 SR |
1325 | raw_spin_lock_irqsave(&global_trace.start_lock, flags); |
1326 | if (--global_trace.stop_count) { | |
1327 | if (global_trace.stop_count < 0) { | |
b06a8301 SR |
1328 | /* Someone screwed up their debugging */ |
1329 | WARN_ON_ONCE(1); | |
2b6080f2 | 1330 | global_trace.stop_count = 0; |
b06a8301 | 1331 | } |
0f048701 SR |
1332 | goto out; |
1333 | } | |
1334 | ||
a2f80714 | 1335 | /* Prevent the buffers from switching */ |
0b9b12c1 | 1336 | arch_spin_lock(&global_trace.max_lock); |
0f048701 | 1337 | |
12883efb | 1338 | buffer = global_trace.trace_buffer.buffer; |
0f048701 SR |
1339 | if (buffer) |
1340 | ring_buffer_record_enable(buffer); | |
1341 | ||
12883efb SRRH |
1342 | #ifdef CONFIG_TRACER_MAX_TRACE |
1343 | buffer = global_trace.max_buffer.buffer; | |
0f048701 SR |
1344 | if (buffer) |
1345 | ring_buffer_record_enable(buffer); | |
12883efb | 1346 | #endif |
0f048701 | 1347 | |
0b9b12c1 | 1348 | arch_spin_unlock(&global_trace.max_lock); |
a2f80714 | 1349 | |
0f048701 SR |
1350 | ftrace_start(); |
1351 | out: | |
2b6080f2 SR |
1352 | raw_spin_unlock_irqrestore(&global_trace.start_lock, flags); |
1353 | } | |
1354 | ||
1355 | static void tracing_start_tr(struct trace_array *tr) | |
1356 | { | |
1357 | struct ring_buffer *buffer; | |
1358 | unsigned long flags; | |
1359 | ||
1360 | if (tracing_disabled) | |
1361 | return; | |
1362 | ||
1363 | /* If global, we need to also start the max tracer */ | |
1364 | if (tr->flags & TRACE_ARRAY_FL_GLOBAL) | |
1365 | return tracing_start(); | |
1366 | ||
1367 | raw_spin_lock_irqsave(&tr->start_lock, flags); | |
1368 | ||
1369 | if (--tr->stop_count) { | |
1370 | if (tr->stop_count < 0) { | |
1371 | /* Someone screwed up their debugging */ | |
1372 | WARN_ON_ONCE(1); | |
1373 | tr->stop_count = 0; | |
1374 | } | |
1375 | goto out; | |
1376 | } | |
1377 | ||
12883efb | 1378 | buffer = tr->trace_buffer.buffer; |
2b6080f2 SR |
1379 | if (buffer) |
1380 | ring_buffer_record_enable(buffer); | |
1381 | ||
1382 | out: | |
1383 | raw_spin_unlock_irqrestore(&tr->start_lock, flags); | |
0f048701 SR |
1384 | } |
1385 | ||
1386 | /** | |
1387 | * tracing_stop - quick stop of the tracer | |
1388 | * | |
1389 | * Light weight way to stop tracing. Use in conjunction with | |
1390 | * tracing_start. | |
1391 | */ | |
1392 | void tracing_stop(void) | |
1393 | { | |
1394 | struct ring_buffer *buffer; | |
1395 | unsigned long flags; | |
1396 | ||
1397 | ftrace_stop(); | |
2b6080f2 SR |
1398 | raw_spin_lock_irqsave(&global_trace.start_lock, flags); |
1399 | if (global_trace.stop_count++) | |
0f048701 SR |
1400 | goto out; |
1401 | ||
a2f80714 | 1402 | /* Prevent the buffers from switching */ |
0b9b12c1 | 1403 | arch_spin_lock(&global_trace.max_lock); |
a2f80714 | 1404 | |
12883efb | 1405 | buffer = global_trace.trace_buffer.buffer; |
0f048701 SR |
1406 | if (buffer) |
1407 | ring_buffer_record_disable(buffer); | |
1408 | ||
12883efb SRRH |
1409 | #ifdef CONFIG_TRACER_MAX_TRACE |
1410 | buffer = global_trace.max_buffer.buffer; | |
0f048701 SR |
1411 | if (buffer) |
1412 | ring_buffer_record_disable(buffer); | |
12883efb | 1413 | #endif |
0f048701 | 1414 | |
0b9b12c1 | 1415 | arch_spin_unlock(&global_trace.max_lock); |
a2f80714 | 1416 | |
0f048701 | 1417 | out: |
2b6080f2 SR |
1418 | raw_spin_unlock_irqrestore(&global_trace.start_lock, flags); |
1419 | } | |
1420 | ||
1421 | static void tracing_stop_tr(struct trace_array *tr) | |
1422 | { | |
1423 | struct ring_buffer *buffer; | |
1424 | unsigned long flags; | |
1425 | ||
1426 | /* If global, we need to also stop the max tracer */ | |
1427 | if (tr->flags & TRACE_ARRAY_FL_GLOBAL) | |
1428 | return tracing_stop(); | |
1429 | ||
1430 | raw_spin_lock_irqsave(&tr->start_lock, flags); | |
1431 | if (tr->stop_count++) | |
1432 | goto out; | |
1433 | ||
12883efb | 1434 | buffer = tr->trace_buffer.buffer; |
2b6080f2 SR |
1435 | if (buffer) |
1436 | ring_buffer_record_disable(buffer); | |
1437 | ||
1438 | out: | |
1439 | raw_spin_unlock_irqrestore(&tr->start_lock, flags); | |
0f048701 SR |
1440 | } |
1441 | ||
e309b41d | 1442 | void trace_stop_cmdline_recording(void); |
bc0c38d1 | 1443 | |
e309b41d | 1444 | static void trace_save_cmdline(struct task_struct *tsk) |
bc0c38d1 | 1445 | { |
a635cf04 | 1446 | unsigned pid, idx; |
bc0c38d1 SR |
1447 | |
1448 | if (!tsk->pid || unlikely(tsk->pid > PID_MAX_DEFAULT)) | |
1449 | return; | |
1450 | ||
1451 | /* | |
1452 | * It's not the end of the world if we don't get | |
1453 | * the lock, but we also don't want to spin | |
1454 | * nor do we want to disable interrupts, | |
1455 | * so if we miss here, then better luck next time. | |
1456 | */ | |
0199c4e6 | 1457 | if (!arch_spin_trylock(&trace_cmdline_lock)) |
bc0c38d1 SR |
1458 | return; |
1459 | ||
1460 | idx = map_pid_to_cmdline[tsk->pid]; | |
2c7eea4c | 1461 | if (idx == NO_CMDLINE_MAP) { |
bc0c38d1 SR |
1462 | idx = (cmdline_idx + 1) % SAVED_CMDLINES; |
1463 | ||
a635cf04 CE |
1464 | /* |
1465 | * Check whether the cmdline buffer at idx has a pid | |
1466 | * mapped. We are going to overwrite that entry so we | |
1467 | * need to clear the map_pid_to_cmdline. Otherwise we | |
1468 | * would read the new comm for the old pid. | |
1469 | */ | |
1470 | pid = map_cmdline_to_pid[idx]; | |
1471 | if (pid != NO_CMDLINE_MAP) | |
1472 | map_pid_to_cmdline[pid] = NO_CMDLINE_MAP; | |
bc0c38d1 | 1473 | |
a635cf04 | 1474 | map_cmdline_to_pid[idx] = tsk->pid; |
bc0c38d1 SR |
1475 | map_pid_to_cmdline[tsk->pid] = idx; |
1476 | ||
1477 | cmdline_idx = idx; | |
1478 | } | |
1479 | ||
1480 | memcpy(&saved_cmdlines[idx], tsk->comm, TASK_COMM_LEN); | |
1481 | ||
0199c4e6 | 1482 | arch_spin_unlock(&trace_cmdline_lock); |
bc0c38d1 SR |
1483 | } |
1484 | ||
4ca53085 | 1485 | void trace_find_cmdline(int pid, char comm[]) |
bc0c38d1 | 1486 | { |
bc0c38d1 SR |
1487 | unsigned map; |
1488 | ||
4ca53085 SR |
1489 | if (!pid) { |
1490 | strcpy(comm, "<idle>"); | |
1491 | return; | |
1492 | } | |
bc0c38d1 | 1493 | |
74bf4076 SR |
1494 | if (WARN_ON_ONCE(pid < 0)) { |
1495 | strcpy(comm, "<XXX>"); | |
1496 | return; | |
1497 | } | |
1498 | ||
4ca53085 SR |
1499 | if (pid > PID_MAX_DEFAULT) { |
1500 | strcpy(comm, "<...>"); | |
1501 | return; | |
1502 | } | |
bc0c38d1 | 1503 | |
5b6045a9 | 1504 | preempt_disable(); |
0199c4e6 | 1505 | arch_spin_lock(&trace_cmdline_lock); |
bc0c38d1 | 1506 | map = map_pid_to_cmdline[pid]; |
50d88758 TG |
1507 | if (map != NO_CMDLINE_MAP) |
1508 | strcpy(comm, saved_cmdlines[map]); | |
1509 | else | |
1510 | strcpy(comm, "<...>"); | |
bc0c38d1 | 1511 | |
0199c4e6 | 1512 | arch_spin_unlock(&trace_cmdline_lock); |
5b6045a9 | 1513 | preempt_enable(); |
bc0c38d1 SR |
1514 | } |
1515 | ||
e309b41d | 1516 | void tracing_record_cmdline(struct task_struct *tsk) |
bc0c38d1 | 1517 | { |
0fb9656d | 1518 | if (atomic_read(&trace_record_cmdline_disabled) || !tracing_is_on()) |
bc0c38d1 SR |
1519 | return; |
1520 | ||
7ffbd48d SR |
1521 | if (!__this_cpu_read(trace_cmdline_save)) |
1522 | return; | |
1523 | ||
1524 | __this_cpu_write(trace_cmdline_save, false); | |
1525 | ||
bc0c38d1 SR |
1526 | trace_save_cmdline(tsk); |
1527 | } | |
1528 | ||
45dcd8b8 | 1529 | void |
38697053 SR |
1530 | tracing_generic_entry_update(struct trace_entry *entry, unsigned long flags, |
1531 | int pc) | |
bc0c38d1 SR |
1532 | { |
1533 | struct task_struct *tsk = current; | |
bc0c38d1 | 1534 | |
777e208d SR |
1535 | entry->preempt_count = pc & 0xff; |
1536 | entry->pid = (tsk) ? tsk->pid : 0; | |
1537 | entry->flags = | |
9244489a | 1538 | #ifdef CONFIG_TRACE_IRQFLAGS_SUPPORT |
2e2ca155 | 1539 | (irqs_disabled_flags(flags) ? TRACE_FLAG_IRQS_OFF : 0) | |
9244489a SR |
1540 | #else |
1541 | TRACE_FLAG_IRQS_NOSUPPORT | | |
1542 | #endif | |
bc0c38d1 SR |
1543 | ((pc & HARDIRQ_MASK) ? TRACE_FLAG_HARDIRQ : 0) | |
1544 | ((pc & SOFTIRQ_MASK) ? TRACE_FLAG_SOFTIRQ : 0) | | |
e5137b50 PZ |
1545 | (tif_need_resched() ? TRACE_FLAG_NEED_RESCHED : 0) | |
1546 | (test_preempt_need_resched() ? TRACE_FLAG_PREEMPT_RESCHED : 0); | |
bc0c38d1 | 1547 | } |
f413cdb8 | 1548 | EXPORT_SYMBOL_GPL(tracing_generic_entry_update); |
bc0c38d1 | 1549 | |
e77405ad SR |
1550 | struct ring_buffer_event * |
1551 | trace_buffer_lock_reserve(struct ring_buffer *buffer, | |
1552 | int type, | |
1553 | unsigned long len, | |
1554 | unsigned long flags, int pc) | |
51a763dd ACM |
1555 | { |
1556 | struct ring_buffer_event *event; | |
1557 | ||
e77405ad | 1558 | event = ring_buffer_lock_reserve(buffer, len); |
51a763dd ACM |
1559 | if (event != NULL) { |
1560 | struct trace_entry *ent = ring_buffer_event_data(event); | |
1561 | ||
1562 | tracing_generic_entry_update(ent, flags, pc); | |
1563 | ent->type = type; | |
1564 | } | |
1565 | ||
1566 | return event; | |
1567 | } | |
51a763dd | 1568 | |
7ffbd48d SR |
1569 | void |
1570 | __buffer_unlock_commit(struct ring_buffer *buffer, struct ring_buffer_event *event) | |
1571 | { | |
1572 | __this_cpu_write(trace_cmdline_save, true); | |
1573 | ring_buffer_unlock_commit(buffer, event); | |
1574 | } | |
1575 | ||
e77405ad SR |
1576 | static inline void |
1577 | __trace_buffer_unlock_commit(struct ring_buffer *buffer, | |
1578 | struct ring_buffer_event *event, | |
0d5c6e1c | 1579 | unsigned long flags, int pc) |
51a763dd | 1580 | { |
7ffbd48d | 1581 | __buffer_unlock_commit(buffer, event); |
51a763dd | 1582 | |
e77405ad SR |
1583 | ftrace_trace_stack(buffer, flags, 6, pc); |
1584 | ftrace_trace_userstack(buffer, flags, pc); | |
07edf712 FW |
1585 | } |
1586 | ||
e77405ad SR |
1587 | void trace_buffer_unlock_commit(struct ring_buffer *buffer, |
1588 | struct ring_buffer_event *event, | |
1589 | unsigned long flags, int pc) | |
07edf712 | 1590 | { |
0d5c6e1c | 1591 | __trace_buffer_unlock_commit(buffer, event, flags, pc); |
51a763dd | 1592 | } |
0d5c6e1c | 1593 | EXPORT_SYMBOL_GPL(trace_buffer_unlock_commit); |
51a763dd | 1594 | |
2c4a33ab SRRH |
1595 | static struct ring_buffer *temp_buffer; |
1596 | ||
ccb469a1 SR |
1597 | struct ring_buffer_event * |
1598 | trace_event_buffer_lock_reserve(struct ring_buffer **current_rb, | |
1599 | struct ftrace_event_file *ftrace_file, | |
1600 | int type, unsigned long len, | |
1601 | unsigned long flags, int pc) | |
1602 | { | |
2c4a33ab SRRH |
1603 | struct ring_buffer_event *entry; |
1604 | ||
12883efb | 1605 | *current_rb = ftrace_file->tr->trace_buffer.buffer; |
2c4a33ab | 1606 | entry = trace_buffer_lock_reserve(*current_rb, |
ccb469a1 | 1607 | type, len, flags, pc); |
2c4a33ab SRRH |
1608 | /* |
1609 | * If tracing is off, but we have triggers enabled | |
1610 | * we still need to look at the event data. Use the temp_buffer | |
1611 | * to store the trace event for the tigger to use. It's recusive | |
1612 | * safe and will not be recorded anywhere. | |
1613 | */ | |
1614 | if (!entry && ftrace_file->flags & FTRACE_EVENT_FL_TRIGGER_COND) { | |
1615 | *current_rb = temp_buffer; | |
1616 | entry = trace_buffer_lock_reserve(*current_rb, | |
1617 | type, len, flags, pc); | |
1618 | } | |
1619 | return entry; | |
ccb469a1 SR |
1620 | } |
1621 | EXPORT_SYMBOL_GPL(trace_event_buffer_lock_reserve); | |
1622 | ||
ef5580d0 | 1623 | struct ring_buffer_event * |
e77405ad SR |
1624 | trace_current_buffer_lock_reserve(struct ring_buffer **current_rb, |
1625 | int type, unsigned long len, | |
ef5580d0 SR |
1626 | unsigned long flags, int pc) |
1627 | { | |
12883efb | 1628 | *current_rb = global_trace.trace_buffer.buffer; |
e77405ad | 1629 | return trace_buffer_lock_reserve(*current_rb, |
ef5580d0 SR |
1630 | type, len, flags, pc); |
1631 | } | |
94487d6d | 1632 | EXPORT_SYMBOL_GPL(trace_current_buffer_lock_reserve); |
ef5580d0 | 1633 | |
e77405ad SR |
1634 | void trace_current_buffer_unlock_commit(struct ring_buffer *buffer, |
1635 | struct ring_buffer_event *event, | |
ef5580d0 SR |
1636 | unsigned long flags, int pc) |
1637 | { | |
0d5c6e1c | 1638 | __trace_buffer_unlock_commit(buffer, event, flags, pc); |
07edf712 | 1639 | } |
94487d6d | 1640 | EXPORT_SYMBOL_GPL(trace_current_buffer_unlock_commit); |
07edf712 | 1641 | |
0d5c6e1c SR |
1642 | void trace_buffer_unlock_commit_regs(struct ring_buffer *buffer, |
1643 | struct ring_buffer_event *event, | |
1644 | unsigned long flags, int pc, | |
1645 | struct pt_regs *regs) | |
1fd8df2c | 1646 | { |
7ffbd48d | 1647 | __buffer_unlock_commit(buffer, event); |
1fd8df2c MH |
1648 | |
1649 | ftrace_trace_stack_regs(buffer, flags, 0, pc, regs); | |
1650 | ftrace_trace_userstack(buffer, flags, pc); | |
1651 | } | |
0d5c6e1c | 1652 | EXPORT_SYMBOL_GPL(trace_buffer_unlock_commit_regs); |
1fd8df2c | 1653 | |
e77405ad SR |
1654 | void trace_current_buffer_discard_commit(struct ring_buffer *buffer, |
1655 | struct ring_buffer_event *event) | |
77d9f465 | 1656 | { |
e77405ad | 1657 | ring_buffer_discard_commit(buffer, event); |
ef5580d0 | 1658 | } |
12acd473 | 1659 | EXPORT_SYMBOL_GPL(trace_current_buffer_discard_commit); |
ef5580d0 | 1660 | |
e309b41d | 1661 | void |
7be42151 | 1662 | trace_function(struct trace_array *tr, |
38697053 SR |
1663 | unsigned long ip, unsigned long parent_ip, unsigned long flags, |
1664 | int pc) | |
bc0c38d1 | 1665 | { |
e1112b4d | 1666 | struct ftrace_event_call *call = &event_function; |
12883efb | 1667 | struct ring_buffer *buffer = tr->trace_buffer.buffer; |
3928a8a2 | 1668 | struct ring_buffer_event *event; |
777e208d | 1669 | struct ftrace_entry *entry; |
bc0c38d1 | 1670 | |
d769041f | 1671 | /* If we are reading the ring buffer, don't trace */ |
dd17c8f7 | 1672 | if (unlikely(__this_cpu_read(ftrace_cpu_disabled))) |
d769041f SR |
1673 | return; |
1674 | ||
e77405ad | 1675 | event = trace_buffer_lock_reserve(buffer, TRACE_FN, sizeof(*entry), |
51a763dd | 1676 | flags, pc); |
3928a8a2 SR |
1677 | if (!event) |
1678 | return; | |
1679 | entry = ring_buffer_event_data(event); | |
777e208d SR |
1680 | entry->ip = ip; |
1681 | entry->parent_ip = parent_ip; | |
e1112b4d | 1682 | |
f306cc82 | 1683 | if (!call_filter_check_discard(call, entry, buffer, event)) |
7ffbd48d | 1684 | __buffer_unlock_commit(buffer, event); |
bc0c38d1 SR |
1685 | } |
1686 | ||
c0a0d0d3 | 1687 | #ifdef CONFIG_STACKTRACE |
4a9bd3f1 SR |
1688 | |
1689 | #define FTRACE_STACK_MAX_ENTRIES (PAGE_SIZE / sizeof(unsigned long)) | |
1690 | struct ftrace_stack { | |
1691 | unsigned long calls[FTRACE_STACK_MAX_ENTRIES]; | |
1692 | }; | |
1693 | ||
1694 | static DEFINE_PER_CPU(struct ftrace_stack, ftrace_stack); | |
1695 | static DEFINE_PER_CPU(int, ftrace_stack_reserve); | |
1696 | ||
e77405ad | 1697 | static void __ftrace_trace_stack(struct ring_buffer *buffer, |
53614991 | 1698 | unsigned long flags, |
1fd8df2c | 1699 | int skip, int pc, struct pt_regs *regs) |
86387f7e | 1700 | { |
e1112b4d | 1701 | struct ftrace_event_call *call = &event_kernel_stack; |
3928a8a2 | 1702 | struct ring_buffer_event *event; |
777e208d | 1703 | struct stack_entry *entry; |
86387f7e | 1704 | struct stack_trace trace; |
4a9bd3f1 SR |
1705 | int use_stack; |
1706 | int size = FTRACE_STACK_ENTRIES; | |
1707 | ||
1708 | trace.nr_entries = 0; | |
1709 | trace.skip = skip; | |
1710 | ||
1711 | /* | |
1712 | * Since events can happen in NMIs there's no safe way to | |
1713 | * use the per cpu ftrace_stacks. We reserve it and if an interrupt | |
1714 | * or NMI comes in, it will just have to use the default | |
1715 | * FTRACE_STACK_SIZE. | |
1716 | */ | |
1717 | preempt_disable_notrace(); | |
1718 | ||
82146529 | 1719 | use_stack = __this_cpu_inc_return(ftrace_stack_reserve); |
4a9bd3f1 SR |
1720 | /* |
1721 | * We don't need any atomic variables, just a barrier. | |
1722 | * If an interrupt comes in, we don't care, because it would | |
1723 | * have exited and put the counter back to what we want. | |
1724 | * We just need a barrier to keep gcc from moving things | |
1725 | * around. | |
1726 | */ | |
1727 | barrier(); | |
1728 | if (use_stack == 1) { | |
bdffd893 | 1729 | trace.entries = this_cpu_ptr(ftrace_stack.calls); |
4a9bd3f1 SR |
1730 | trace.max_entries = FTRACE_STACK_MAX_ENTRIES; |
1731 | ||
1732 | if (regs) | |
1733 | save_stack_trace_regs(regs, &trace); | |
1734 | else | |
1735 | save_stack_trace(&trace); | |
1736 | ||
1737 | if (trace.nr_entries > size) | |
1738 | size = trace.nr_entries; | |
1739 | } else | |
1740 | /* From now on, use_stack is a boolean */ | |
1741 | use_stack = 0; | |
1742 | ||
1743 | size *= sizeof(unsigned long); | |
86387f7e | 1744 | |
e77405ad | 1745 | event = trace_buffer_lock_reserve(buffer, TRACE_STACK, |
4a9bd3f1 | 1746 | sizeof(*entry) + size, flags, pc); |
3928a8a2 | 1747 | if (!event) |
4a9bd3f1 SR |
1748 | goto out; |
1749 | entry = ring_buffer_event_data(event); | |
86387f7e | 1750 | |
4a9bd3f1 SR |
1751 | memset(&entry->caller, 0, size); |
1752 | ||
1753 | if (use_stack) | |
1754 | memcpy(&entry->caller, trace.entries, | |
1755 | trace.nr_entries * sizeof(unsigned long)); | |
1756 | else { | |
1757 | trace.max_entries = FTRACE_STACK_ENTRIES; | |
1758 | trace.entries = entry->caller; | |
1759 | if (regs) | |
1760 | save_stack_trace_regs(regs, &trace); | |
1761 | else | |
1762 | save_stack_trace(&trace); | |
1763 | } | |
1764 | ||
1765 | entry->size = trace.nr_entries; | |
86387f7e | 1766 | |
f306cc82 | 1767 | if (!call_filter_check_discard(call, entry, buffer, event)) |
7ffbd48d | 1768 | __buffer_unlock_commit(buffer, event); |
4a9bd3f1 SR |
1769 | |
1770 | out: | |
1771 | /* Again, don't let gcc optimize things here */ | |
1772 | barrier(); | |
82146529 | 1773 | __this_cpu_dec(ftrace_stack_reserve); |
4a9bd3f1 SR |
1774 | preempt_enable_notrace(); |
1775 | ||
f0a920d5 IM |
1776 | } |
1777 | ||
1fd8df2c MH |
1778 | void ftrace_trace_stack_regs(struct ring_buffer *buffer, unsigned long flags, |
1779 | int skip, int pc, struct pt_regs *regs) | |
1780 | { | |
1781 | if (!(trace_flags & TRACE_ITER_STACKTRACE)) | |
1782 | return; | |
1783 | ||
1784 | __ftrace_trace_stack(buffer, flags, skip, pc, regs); | |
1785 | } | |
1786 | ||
e77405ad SR |
1787 | void ftrace_trace_stack(struct ring_buffer *buffer, unsigned long flags, |
1788 | int skip, int pc) | |
53614991 SR |
1789 | { |
1790 | if (!(trace_flags & TRACE_ITER_STACKTRACE)) | |
1791 | return; | |
1792 | ||
1fd8df2c | 1793 | __ftrace_trace_stack(buffer, flags, skip, pc, NULL); |
53614991 SR |
1794 | } |
1795 | ||
c0a0d0d3 FW |
1796 | void __trace_stack(struct trace_array *tr, unsigned long flags, int skip, |
1797 | int pc) | |
38697053 | 1798 | { |
12883efb | 1799 | __ftrace_trace_stack(tr->trace_buffer.buffer, flags, skip, pc, NULL); |
38697053 SR |
1800 | } |
1801 | ||
03889384 SR |
1802 | /** |
1803 | * trace_dump_stack - record a stack back trace in the trace buffer | |
c142be8e | 1804 | * @skip: Number of functions to skip (helper handlers) |
03889384 | 1805 | */ |
c142be8e | 1806 | void trace_dump_stack(int skip) |
03889384 SR |
1807 | { |
1808 | unsigned long flags; | |
1809 | ||
1810 | if (tracing_disabled || tracing_selftest_running) | |
e36c5458 | 1811 | return; |
03889384 SR |
1812 | |
1813 | local_save_flags(flags); | |
1814 | ||
c142be8e SRRH |
1815 | /* |
1816 | * Skip 3 more, seems to get us at the caller of | |
1817 | * this function. | |
1818 | */ | |
1819 | skip += 3; | |
1820 | __ftrace_trace_stack(global_trace.trace_buffer.buffer, | |
1821 | flags, skip, preempt_count(), NULL); | |
03889384 SR |
1822 | } |
1823 | ||
91e86e56 SR |
1824 | static DEFINE_PER_CPU(int, user_stack_count); |
1825 | ||
e77405ad SR |
1826 | void |
1827 | ftrace_trace_userstack(struct ring_buffer *buffer, unsigned long flags, int pc) | |
02b67518 | 1828 | { |
e1112b4d | 1829 | struct ftrace_event_call *call = &event_user_stack; |
8d7c6a96 | 1830 | struct ring_buffer_event *event; |
02b67518 TE |
1831 | struct userstack_entry *entry; |
1832 | struct stack_trace trace; | |
02b67518 TE |
1833 | |
1834 | if (!(trace_flags & TRACE_ITER_USERSTACKTRACE)) | |
1835 | return; | |
1836 | ||
b6345879 SR |
1837 | /* |
1838 | * NMIs can not handle page faults, even with fix ups. | |
1839 | * The save user stack can (and often does) fault. | |
1840 | */ | |
1841 | if (unlikely(in_nmi())) | |
1842 | return; | |
02b67518 | 1843 | |
91e86e56 SR |
1844 | /* |
1845 | * prevent recursion, since the user stack tracing may | |
1846 | * trigger other kernel events. | |
1847 | */ | |
1848 | preempt_disable(); | |
1849 | if (__this_cpu_read(user_stack_count)) | |
1850 | goto out; | |
1851 | ||
1852 | __this_cpu_inc(user_stack_count); | |
1853 | ||
e77405ad | 1854 | event = trace_buffer_lock_reserve(buffer, TRACE_USER_STACK, |
51a763dd | 1855 | sizeof(*entry), flags, pc); |
02b67518 | 1856 | if (!event) |
1dbd1951 | 1857 | goto out_drop_count; |
02b67518 | 1858 | entry = ring_buffer_event_data(event); |
02b67518 | 1859 | |
48659d31 | 1860 | entry->tgid = current->tgid; |
02b67518 TE |
1861 | memset(&entry->caller, 0, sizeof(entry->caller)); |
1862 | ||
1863 | trace.nr_entries = 0; | |
1864 | trace.max_entries = FTRACE_STACK_ENTRIES; | |
1865 | trace.skip = 0; | |
1866 | trace.entries = entry->caller; | |
1867 | ||
1868 | save_stack_trace_user(&trace); | |
f306cc82 | 1869 | if (!call_filter_check_discard(call, entry, buffer, event)) |
7ffbd48d | 1870 | __buffer_unlock_commit(buffer, event); |
91e86e56 | 1871 | |
1dbd1951 | 1872 | out_drop_count: |
91e86e56 | 1873 | __this_cpu_dec(user_stack_count); |
91e86e56 SR |
1874 | out: |
1875 | preempt_enable(); | |
02b67518 TE |
1876 | } |
1877 | ||
4fd27358 HE |
1878 | #ifdef UNUSED |
1879 | static void __trace_userstack(struct trace_array *tr, unsigned long flags) | |
02b67518 | 1880 | { |
7be42151 | 1881 | ftrace_trace_userstack(tr, flags, preempt_count()); |
02b67518 | 1882 | } |
4fd27358 | 1883 | #endif /* UNUSED */ |
02b67518 | 1884 | |
c0a0d0d3 FW |
1885 | #endif /* CONFIG_STACKTRACE */ |
1886 | ||
07d777fe SR |
1887 | /* created for use with alloc_percpu */ |
1888 | struct trace_buffer_struct { | |
1889 | char buffer[TRACE_BUF_SIZE]; | |
1890 | }; | |
1891 | ||
1892 | static struct trace_buffer_struct *trace_percpu_buffer; | |
1893 | static struct trace_buffer_struct *trace_percpu_sirq_buffer; | |
1894 | static struct trace_buffer_struct *trace_percpu_irq_buffer; | |
1895 | static struct trace_buffer_struct *trace_percpu_nmi_buffer; | |
1896 | ||
1897 | /* | |
1898 | * The buffer used is dependent on the context. There is a per cpu | |
1899 | * buffer for normal context, softirq contex, hard irq context and | |
1900 | * for NMI context. Thise allows for lockless recording. | |
1901 | * | |
1902 | * Note, if the buffers failed to be allocated, then this returns NULL | |
1903 | */ | |
1904 | static char *get_trace_buf(void) | |
1905 | { | |
1906 | struct trace_buffer_struct *percpu_buffer; | |
07d777fe SR |
1907 | |
1908 | /* | |
1909 | * If we have allocated per cpu buffers, then we do not | |
1910 | * need to do any locking. | |
1911 | */ | |
1912 | if (in_nmi()) | |
1913 | percpu_buffer = trace_percpu_nmi_buffer; | |
1914 | else if (in_irq()) | |
1915 | percpu_buffer = trace_percpu_irq_buffer; | |
1916 | else if (in_softirq()) | |
1917 | percpu_buffer = trace_percpu_sirq_buffer; | |
1918 | else | |
1919 | percpu_buffer = trace_percpu_buffer; | |
1920 | ||
1921 | if (!percpu_buffer) | |
1922 | return NULL; | |
1923 | ||
d8a0349c | 1924 | return this_cpu_ptr(&percpu_buffer->buffer[0]); |
07d777fe SR |
1925 | } |
1926 | ||
1927 | static int alloc_percpu_trace_buffer(void) | |
1928 | { | |
1929 | struct trace_buffer_struct *buffers; | |
1930 | struct trace_buffer_struct *sirq_buffers; | |
1931 | struct trace_buffer_struct *irq_buffers; | |
1932 | struct trace_buffer_struct *nmi_buffers; | |
1933 | ||
1934 | buffers = alloc_percpu(struct trace_buffer_struct); | |
1935 | if (!buffers) | |
1936 | goto err_warn; | |
1937 | ||
1938 | sirq_buffers = alloc_percpu(struct trace_buffer_struct); | |
1939 | if (!sirq_buffers) | |
1940 | goto err_sirq; | |
1941 | ||
1942 | irq_buffers = alloc_percpu(struct trace_buffer_struct); | |
1943 | if (!irq_buffers) | |
1944 | goto err_irq; | |
1945 | ||
1946 | nmi_buffers = alloc_percpu(struct trace_buffer_struct); | |
1947 | if (!nmi_buffers) | |
1948 | goto err_nmi; | |
1949 | ||
1950 | trace_percpu_buffer = buffers; | |
1951 | trace_percpu_sirq_buffer = sirq_buffers; | |
1952 | trace_percpu_irq_buffer = irq_buffers; | |
1953 | trace_percpu_nmi_buffer = nmi_buffers; | |
1954 | ||
1955 | return 0; | |
1956 | ||
1957 | err_nmi: | |
1958 | free_percpu(irq_buffers); | |
1959 | err_irq: | |
1960 | free_percpu(sirq_buffers); | |
1961 | err_sirq: | |
1962 | free_percpu(buffers); | |
1963 | err_warn: | |
1964 | WARN(1, "Could not allocate percpu trace_printk buffer"); | |
1965 | return -ENOMEM; | |
1966 | } | |
1967 | ||
81698831 SR |
1968 | static int buffers_allocated; |
1969 | ||
07d777fe SR |
1970 | void trace_printk_init_buffers(void) |
1971 | { | |
07d777fe SR |
1972 | if (buffers_allocated) |
1973 | return; | |
1974 | ||
1975 | if (alloc_percpu_trace_buffer()) | |
1976 | return; | |
1977 | ||
2184db46 SR |
1978 | /* trace_printk() is for debug use only. Don't use it in production. */ |
1979 | ||
1980 | pr_warning("\n**********************************************************\n"); | |
1981 | pr_warning("** NOTICE NOTICE NOTICE NOTICE NOTICE NOTICE NOTICE **\n"); | |
1982 | pr_warning("** **\n"); | |
1983 | pr_warning("** trace_printk() being used. Allocating extra memory. **\n"); | |
1984 | pr_warning("** **\n"); | |
1985 | pr_warning("** This means that this is a DEBUG kernel and it is **\n"); | |
1986 | pr_warning("** unsafe for produciton use. **\n"); | |
1987 | pr_warning("** **\n"); | |
1988 | pr_warning("** If you see this message and you are not debugging **\n"); | |
1989 | pr_warning("** the kernel, report this immediately to your vendor! **\n"); | |
1990 | pr_warning("** **\n"); | |
1991 | pr_warning("** NOTICE NOTICE NOTICE NOTICE NOTICE NOTICE NOTICE **\n"); | |
1992 | pr_warning("**********************************************************\n"); | |
07d777fe | 1993 | |
b382ede6 SR |
1994 | /* Expand the buffers to set size */ |
1995 | tracing_update_buffers(); | |
1996 | ||
07d777fe | 1997 | buffers_allocated = 1; |
81698831 SR |
1998 | |
1999 | /* | |
2000 | * trace_printk_init_buffers() can be called by modules. | |
2001 | * If that happens, then we need to start cmdline recording | |
2002 | * directly here. If the global_trace.buffer is already | |
2003 | * allocated here, then this was called by module code. | |
2004 | */ | |
12883efb | 2005 | if (global_trace.trace_buffer.buffer) |
81698831 SR |
2006 | tracing_start_cmdline_record(); |
2007 | } | |
2008 | ||
2009 | void trace_printk_start_comm(void) | |
2010 | { | |
2011 | /* Start tracing comms if trace printk is set */ | |
2012 | if (!buffers_allocated) | |
2013 | return; | |
2014 | tracing_start_cmdline_record(); | |
2015 | } | |
2016 | ||
2017 | static void trace_printk_start_stop_comm(int enabled) | |
2018 | { | |
2019 | if (!buffers_allocated) | |
2020 | return; | |
2021 | ||
2022 | if (enabled) | |
2023 | tracing_start_cmdline_record(); | |
2024 | else | |
2025 | tracing_stop_cmdline_record(); | |
07d777fe SR |
2026 | } |
2027 | ||
769b0441 | 2028 | /** |
48ead020 | 2029 | * trace_vbprintk - write binary msg to tracing buffer |
769b0441 FW |
2030 | * |
2031 | */ | |
40ce74f1 | 2032 | int trace_vbprintk(unsigned long ip, const char *fmt, va_list args) |
769b0441 | 2033 | { |
e1112b4d | 2034 | struct ftrace_event_call *call = &event_bprint; |
769b0441 | 2035 | struct ring_buffer_event *event; |
e77405ad | 2036 | struct ring_buffer *buffer; |
769b0441 | 2037 | struct trace_array *tr = &global_trace; |
48ead020 | 2038 | struct bprint_entry *entry; |
769b0441 | 2039 | unsigned long flags; |
07d777fe SR |
2040 | char *tbuffer; |
2041 | int len = 0, size, pc; | |
769b0441 FW |
2042 | |
2043 | if (unlikely(tracing_selftest_running || tracing_disabled)) | |
2044 | return 0; | |
2045 | ||
2046 | /* Don't pollute graph traces with trace_vprintk internals */ | |
2047 | pause_graph_tracing(); | |
2048 | ||
2049 | pc = preempt_count(); | |
5168ae50 | 2050 | preempt_disable_notrace(); |
769b0441 | 2051 | |
07d777fe SR |
2052 | tbuffer = get_trace_buf(); |
2053 | if (!tbuffer) { | |
2054 | len = 0; | |
769b0441 | 2055 | goto out; |
07d777fe | 2056 | } |
769b0441 | 2057 | |
07d777fe | 2058 | len = vbin_printf((u32 *)tbuffer, TRACE_BUF_SIZE/sizeof(int), fmt, args); |
769b0441 | 2059 | |
07d777fe SR |
2060 | if (len > TRACE_BUF_SIZE/sizeof(int) || len < 0) |
2061 | goto out; | |
769b0441 | 2062 | |
07d777fe | 2063 | local_save_flags(flags); |
769b0441 | 2064 | size = sizeof(*entry) + sizeof(u32) * len; |
12883efb | 2065 | buffer = tr->trace_buffer.buffer; |
e77405ad SR |
2066 | event = trace_buffer_lock_reserve(buffer, TRACE_BPRINT, size, |
2067 | flags, pc); | |
769b0441 | 2068 | if (!event) |
07d777fe | 2069 | goto out; |
769b0441 FW |
2070 | entry = ring_buffer_event_data(event); |
2071 | entry->ip = ip; | |
769b0441 FW |
2072 | entry->fmt = fmt; |
2073 | ||
07d777fe | 2074 | memcpy(entry->buf, tbuffer, sizeof(u32) * len); |
f306cc82 | 2075 | if (!call_filter_check_discard(call, entry, buffer, event)) { |
7ffbd48d | 2076 | __buffer_unlock_commit(buffer, event); |
d931369b SR |
2077 | ftrace_trace_stack(buffer, flags, 6, pc); |
2078 | } | |
769b0441 | 2079 | |
769b0441 | 2080 | out: |
5168ae50 | 2081 | preempt_enable_notrace(); |
769b0441 FW |
2082 | unpause_graph_tracing(); |
2083 | ||
2084 | return len; | |
2085 | } | |
48ead020 FW |
2086 | EXPORT_SYMBOL_GPL(trace_vbprintk); |
2087 | ||
12883efb SRRH |
2088 | static int |
2089 | __trace_array_vprintk(struct ring_buffer *buffer, | |
2090 | unsigned long ip, const char *fmt, va_list args) | |
48ead020 | 2091 | { |
e1112b4d | 2092 | struct ftrace_event_call *call = &event_print; |
48ead020 | 2093 | struct ring_buffer_event *event; |
07d777fe | 2094 | int len = 0, size, pc; |
48ead020 | 2095 | struct print_entry *entry; |
07d777fe SR |
2096 | unsigned long flags; |
2097 | char *tbuffer; | |
48ead020 FW |
2098 | |
2099 | if (tracing_disabled || tracing_selftest_running) | |
2100 | return 0; | |
2101 | ||
07d777fe SR |
2102 | /* Don't pollute graph traces with trace_vprintk internals */ |
2103 | pause_graph_tracing(); | |
2104 | ||
48ead020 FW |
2105 | pc = preempt_count(); |
2106 | preempt_disable_notrace(); | |
48ead020 | 2107 | |
07d777fe SR |
2108 | |
2109 | tbuffer = get_trace_buf(); | |
2110 | if (!tbuffer) { | |
2111 | len = 0; | |
48ead020 | 2112 | goto out; |
07d777fe | 2113 | } |
48ead020 | 2114 | |
07d777fe SR |
2115 | len = vsnprintf(tbuffer, TRACE_BUF_SIZE, fmt, args); |
2116 | if (len > TRACE_BUF_SIZE) | |
2117 | goto out; | |
48ead020 | 2118 | |
07d777fe | 2119 | local_save_flags(flags); |
48ead020 | 2120 | size = sizeof(*entry) + len + 1; |
e77405ad | 2121 | event = trace_buffer_lock_reserve(buffer, TRACE_PRINT, size, |
07d777fe | 2122 | flags, pc); |
48ead020 | 2123 | if (!event) |
07d777fe | 2124 | goto out; |
48ead020 | 2125 | entry = ring_buffer_event_data(event); |
c13d2f7c | 2126 | entry->ip = ip; |
48ead020 | 2127 | |
07d777fe | 2128 | memcpy(&entry->buf, tbuffer, len); |
c13d2f7c | 2129 | entry->buf[len] = '\0'; |
f306cc82 | 2130 | if (!call_filter_check_discard(call, entry, buffer, event)) { |
7ffbd48d | 2131 | __buffer_unlock_commit(buffer, event); |
07d777fe | 2132 | ftrace_trace_stack(buffer, flags, 6, pc); |
d931369b | 2133 | } |
48ead020 FW |
2134 | out: |
2135 | preempt_enable_notrace(); | |
07d777fe | 2136 | unpause_graph_tracing(); |
48ead020 FW |
2137 | |
2138 | return len; | |
2139 | } | |
659372d3 | 2140 | |
12883efb SRRH |
2141 | int trace_array_vprintk(struct trace_array *tr, |
2142 | unsigned long ip, const char *fmt, va_list args) | |
2143 | { | |
2144 | return __trace_array_vprintk(tr->trace_buffer.buffer, ip, fmt, args); | |
2145 | } | |
2146 | ||
2147 | int trace_array_printk(struct trace_array *tr, | |
2148 | unsigned long ip, const char *fmt, ...) | |
2149 | { | |
2150 | int ret; | |
2151 | va_list ap; | |
2152 | ||
2153 | if (!(trace_flags & TRACE_ITER_PRINTK)) | |
2154 | return 0; | |
2155 | ||
2156 | va_start(ap, fmt); | |
2157 | ret = trace_array_vprintk(tr, ip, fmt, ap); | |
2158 | va_end(ap); | |
2159 | return ret; | |
2160 | } | |
2161 | ||
2162 | int trace_array_printk_buf(struct ring_buffer *buffer, | |
2163 | unsigned long ip, const char *fmt, ...) | |
2164 | { | |
2165 | int ret; | |
2166 | va_list ap; | |
2167 | ||
2168 | if (!(trace_flags & TRACE_ITER_PRINTK)) | |
2169 | return 0; | |
2170 | ||
2171 | va_start(ap, fmt); | |
2172 | ret = __trace_array_vprintk(buffer, ip, fmt, ap); | |
2173 | va_end(ap); | |
2174 | return ret; | |
2175 | } | |
2176 | ||
659372d3 SR |
2177 | int trace_vprintk(unsigned long ip, const char *fmt, va_list args) |
2178 | { | |
a813a159 | 2179 | return trace_array_vprintk(&global_trace, ip, fmt, args); |
659372d3 | 2180 | } |
769b0441 FW |
2181 | EXPORT_SYMBOL_GPL(trace_vprintk); |
2182 | ||
e2ac8ef5 | 2183 | static void trace_iterator_increment(struct trace_iterator *iter) |
5a90f577 | 2184 | { |
6d158a81 SR |
2185 | struct ring_buffer_iter *buf_iter = trace_buffer_iter(iter, iter->cpu); |
2186 | ||
5a90f577 | 2187 | iter->idx++; |
6d158a81 SR |
2188 | if (buf_iter) |
2189 | ring_buffer_read(buf_iter, NULL); | |
5a90f577 SR |
2190 | } |
2191 | ||
e309b41d | 2192 | static struct trace_entry * |
bc21b478 SR |
2193 | peek_next_entry(struct trace_iterator *iter, int cpu, u64 *ts, |
2194 | unsigned long *lost_events) | |
dd0e545f | 2195 | { |
3928a8a2 | 2196 | struct ring_buffer_event *event; |
6d158a81 | 2197 | struct ring_buffer_iter *buf_iter = trace_buffer_iter(iter, cpu); |
dd0e545f | 2198 | |
d769041f SR |
2199 | if (buf_iter) |
2200 | event = ring_buffer_iter_peek(buf_iter, ts); | |
2201 | else | |
12883efb | 2202 | event = ring_buffer_peek(iter->trace_buffer->buffer, cpu, ts, |
bc21b478 | 2203 | lost_events); |
d769041f | 2204 | |
4a9bd3f1 SR |
2205 | if (event) { |
2206 | iter->ent_size = ring_buffer_event_length(event); | |
2207 | return ring_buffer_event_data(event); | |
2208 | } | |
2209 | iter->ent_size = 0; | |
2210 | return NULL; | |
dd0e545f | 2211 | } |
d769041f | 2212 | |
dd0e545f | 2213 | static struct trace_entry * |
bc21b478 SR |
2214 | __find_next_entry(struct trace_iterator *iter, int *ent_cpu, |
2215 | unsigned long *missing_events, u64 *ent_ts) | |
bc0c38d1 | 2216 | { |
12883efb | 2217 | struct ring_buffer *buffer = iter->trace_buffer->buffer; |
bc0c38d1 | 2218 | struct trace_entry *ent, *next = NULL; |
aa27497c | 2219 | unsigned long lost_events = 0, next_lost = 0; |
b04cc6b1 | 2220 | int cpu_file = iter->cpu_file; |
3928a8a2 | 2221 | u64 next_ts = 0, ts; |
bc0c38d1 | 2222 | int next_cpu = -1; |
12b5da34 | 2223 | int next_size = 0; |
bc0c38d1 SR |
2224 | int cpu; |
2225 | ||
b04cc6b1 FW |
2226 | /* |
2227 | * If we are in a per_cpu trace file, don't bother by iterating over | |
2228 | * all cpu and peek directly. | |
2229 | */ | |
ae3b5093 | 2230 | if (cpu_file > RING_BUFFER_ALL_CPUS) { |
b04cc6b1 FW |
2231 | if (ring_buffer_empty_cpu(buffer, cpu_file)) |
2232 | return NULL; | |
bc21b478 | 2233 | ent = peek_next_entry(iter, cpu_file, ent_ts, missing_events); |
b04cc6b1 FW |
2234 | if (ent_cpu) |
2235 | *ent_cpu = cpu_file; | |
2236 | ||
2237 | return ent; | |
2238 | } | |
2239 | ||
ab46428c | 2240 | for_each_tracing_cpu(cpu) { |
dd0e545f | 2241 | |
3928a8a2 SR |
2242 | if (ring_buffer_empty_cpu(buffer, cpu)) |
2243 | continue; | |
dd0e545f | 2244 | |
bc21b478 | 2245 | ent = peek_next_entry(iter, cpu, &ts, &lost_events); |
dd0e545f | 2246 | |
cdd31cd2 IM |
2247 | /* |
2248 | * Pick the entry with the smallest timestamp: | |
2249 | */ | |
3928a8a2 | 2250 | if (ent && (!next || ts < next_ts)) { |
bc0c38d1 SR |
2251 | next = ent; |
2252 | next_cpu = cpu; | |
3928a8a2 | 2253 | next_ts = ts; |
bc21b478 | 2254 | next_lost = lost_events; |
12b5da34 | 2255 | next_size = iter->ent_size; |
bc0c38d1 SR |
2256 | } |
2257 | } | |
2258 | ||
12b5da34 SR |
2259 | iter->ent_size = next_size; |
2260 | ||
bc0c38d1 SR |
2261 | if (ent_cpu) |
2262 | *ent_cpu = next_cpu; | |
2263 | ||
3928a8a2 SR |
2264 | if (ent_ts) |
2265 | *ent_ts = next_ts; | |
2266 | ||
bc21b478 SR |
2267 | if (missing_events) |
2268 | *missing_events = next_lost; | |
2269 | ||
bc0c38d1 SR |
2270 | return next; |
2271 | } | |
2272 | ||
dd0e545f | 2273 | /* Find the next real entry, without updating the iterator itself */ |
c4a8e8be FW |
2274 | struct trace_entry *trace_find_next_entry(struct trace_iterator *iter, |
2275 | int *ent_cpu, u64 *ent_ts) | |
bc0c38d1 | 2276 | { |
bc21b478 | 2277 | return __find_next_entry(iter, ent_cpu, NULL, ent_ts); |
dd0e545f SR |
2278 | } |
2279 | ||
2280 | /* Find the next real entry, and increment the iterator to the next entry */ | |
955b61e5 | 2281 | void *trace_find_next_entry_inc(struct trace_iterator *iter) |
dd0e545f | 2282 | { |
bc21b478 SR |
2283 | iter->ent = __find_next_entry(iter, &iter->cpu, |
2284 | &iter->lost_events, &iter->ts); | |
dd0e545f | 2285 | |
3928a8a2 | 2286 | if (iter->ent) |
e2ac8ef5 | 2287 | trace_iterator_increment(iter); |
dd0e545f | 2288 | |
3928a8a2 | 2289 | return iter->ent ? iter : NULL; |
b3806b43 | 2290 | } |
bc0c38d1 | 2291 | |
e309b41d | 2292 | static void trace_consume(struct trace_iterator *iter) |
b3806b43 | 2293 | { |
12883efb | 2294 | ring_buffer_consume(iter->trace_buffer->buffer, iter->cpu, &iter->ts, |
bc21b478 | 2295 | &iter->lost_events); |
bc0c38d1 SR |
2296 | } |
2297 | ||
e309b41d | 2298 | static void *s_next(struct seq_file *m, void *v, loff_t *pos) |
bc0c38d1 SR |
2299 | { |
2300 | struct trace_iterator *iter = m->private; | |
bc0c38d1 | 2301 | int i = (int)*pos; |
4e3c3333 | 2302 | void *ent; |
bc0c38d1 | 2303 | |
a63ce5b3 SR |
2304 | WARN_ON_ONCE(iter->leftover); |
2305 | ||
bc0c38d1 SR |
2306 | (*pos)++; |
2307 | ||
2308 | /* can't go backwards */ | |
2309 | if (iter->idx > i) | |
2310 | return NULL; | |
2311 | ||
2312 | if (iter->idx < 0) | |
955b61e5 | 2313 | ent = trace_find_next_entry_inc(iter); |
bc0c38d1 SR |
2314 | else |
2315 | ent = iter; | |
2316 | ||
2317 | while (ent && iter->idx < i) | |
955b61e5 | 2318 | ent = trace_find_next_entry_inc(iter); |
bc0c38d1 SR |
2319 | |
2320 | iter->pos = *pos; | |
2321 | ||
bc0c38d1 SR |
2322 | return ent; |
2323 | } | |
2324 | ||
955b61e5 | 2325 | void tracing_iter_reset(struct trace_iterator *iter, int cpu) |
2f26ebd5 | 2326 | { |
2f26ebd5 SR |
2327 | struct ring_buffer_event *event; |
2328 | struct ring_buffer_iter *buf_iter; | |
2329 | unsigned long entries = 0; | |
2330 | u64 ts; | |
2331 | ||
12883efb | 2332 | per_cpu_ptr(iter->trace_buffer->data, cpu)->skipped_entries = 0; |
2f26ebd5 | 2333 | |
6d158a81 SR |
2334 | buf_iter = trace_buffer_iter(iter, cpu); |
2335 | if (!buf_iter) | |
2f26ebd5 SR |
2336 | return; |
2337 | ||
2f26ebd5 SR |
2338 | ring_buffer_iter_reset(buf_iter); |
2339 | ||
2340 | /* | |
2341 | * We could have the case with the max latency tracers | |
2342 | * that a reset never took place on a cpu. This is evident | |
2343 | * by the timestamp being before the start of the buffer. | |
2344 | */ | |
2345 | while ((event = ring_buffer_iter_peek(buf_iter, &ts))) { | |
12883efb | 2346 | if (ts >= iter->trace_buffer->time_start) |
2f26ebd5 SR |
2347 | break; |
2348 | entries++; | |
2349 | ring_buffer_read(buf_iter, NULL); | |
2350 | } | |
2351 | ||
12883efb | 2352 | per_cpu_ptr(iter->trace_buffer->data, cpu)->skipped_entries = entries; |
2f26ebd5 SR |
2353 | } |
2354 | ||
d7350c3f | 2355 | /* |
d7350c3f FW |
2356 | * The current tracer is copied to avoid a global locking |
2357 | * all around. | |
2358 | */ | |
bc0c38d1 SR |
2359 | static void *s_start(struct seq_file *m, loff_t *pos) |
2360 | { | |
2361 | struct trace_iterator *iter = m->private; | |
2b6080f2 | 2362 | struct trace_array *tr = iter->tr; |
b04cc6b1 | 2363 | int cpu_file = iter->cpu_file; |
bc0c38d1 SR |
2364 | void *p = NULL; |
2365 | loff_t l = 0; | |
3928a8a2 | 2366 | int cpu; |
bc0c38d1 | 2367 | |
2fd196ec HT |
2368 | /* |
2369 | * copy the tracer to avoid using a global lock all around. | |
2370 | * iter->trace is a copy of current_trace, the pointer to the | |
2371 | * name may be used instead of a strcmp(), as iter->trace->name | |
2372 | * will point to the same string as current_trace->name. | |
2373 | */ | |
bc0c38d1 | 2374 | mutex_lock(&trace_types_lock); |
2b6080f2 SR |
2375 | if (unlikely(tr->current_trace && iter->trace->name != tr->current_trace->name)) |
2376 | *iter->trace = *tr->current_trace; | |
d7350c3f | 2377 | mutex_unlock(&trace_types_lock); |
bc0c38d1 | 2378 | |
12883efb | 2379 | #ifdef CONFIG_TRACER_MAX_TRACE |
debdd57f HT |
2380 | if (iter->snapshot && iter->trace->use_max_tr) |
2381 | return ERR_PTR(-EBUSY); | |
12883efb | 2382 | #endif |
debdd57f HT |
2383 | |
2384 | if (!iter->snapshot) | |
2385 | atomic_inc(&trace_record_cmdline_disabled); | |
bc0c38d1 | 2386 | |
bc0c38d1 SR |
2387 | if (*pos != iter->pos) { |
2388 | iter->ent = NULL; | |
2389 | iter->cpu = 0; | |
2390 | iter->idx = -1; | |
2391 | ||
ae3b5093 | 2392 | if (cpu_file == RING_BUFFER_ALL_CPUS) { |
b04cc6b1 | 2393 | for_each_tracing_cpu(cpu) |
2f26ebd5 | 2394 | tracing_iter_reset(iter, cpu); |
b04cc6b1 | 2395 | } else |
2f26ebd5 | 2396 | tracing_iter_reset(iter, cpu_file); |
bc0c38d1 | 2397 | |
ac91d854 | 2398 | iter->leftover = 0; |
bc0c38d1 SR |
2399 | for (p = iter; p && l < *pos; p = s_next(m, p, &l)) |
2400 | ; | |
2401 | ||
2402 | } else { | |
a63ce5b3 SR |
2403 | /* |
2404 | * If we overflowed the seq_file before, then we want | |
2405 | * to just reuse the trace_seq buffer again. | |
2406 | */ | |
2407 | if (iter->leftover) | |
2408 | p = iter; | |
2409 | else { | |
2410 | l = *pos - 1; | |
2411 | p = s_next(m, p, &l); | |
2412 | } | |
bc0c38d1 SR |
2413 | } |
2414 | ||
4f535968 | 2415 | trace_event_read_lock(); |
7e53bd42 | 2416 | trace_access_lock(cpu_file); |
bc0c38d1 SR |
2417 | return p; |
2418 | } | |
2419 | ||
2420 | static void s_stop(struct seq_file *m, void *p) | |
2421 | { | |
7e53bd42 LJ |
2422 | struct trace_iterator *iter = m->private; |
2423 | ||
12883efb | 2424 | #ifdef CONFIG_TRACER_MAX_TRACE |
debdd57f HT |
2425 | if (iter->snapshot && iter->trace->use_max_tr) |
2426 | return; | |
12883efb | 2427 | #endif |
debdd57f HT |
2428 | |
2429 | if (!iter->snapshot) | |
2430 | atomic_dec(&trace_record_cmdline_disabled); | |
12883efb | 2431 | |
7e53bd42 | 2432 | trace_access_unlock(iter->cpu_file); |
4f535968 | 2433 | trace_event_read_unlock(); |
bc0c38d1 SR |
2434 | } |
2435 | ||
39eaf7ef | 2436 | static void |
12883efb SRRH |
2437 | get_total_entries(struct trace_buffer *buf, |
2438 | unsigned long *total, unsigned long *entries) | |
39eaf7ef SR |
2439 | { |
2440 | unsigned long count; | |
2441 | int cpu; | |
2442 | ||
2443 | *total = 0; | |
2444 | *entries = 0; | |
2445 | ||
2446 | for_each_tracing_cpu(cpu) { | |
12883efb | 2447 | count = ring_buffer_entries_cpu(buf->buffer, cpu); |
39eaf7ef SR |
2448 | /* |
2449 | * If this buffer has skipped entries, then we hold all | |
2450 | * entries for the trace and we need to ignore the | |
2451 | * ones before the time stamp. | |
2452 | */ | |
12883efb SRRH |
2453 | if (per_cpu_ptr(buf->data, cpu)->skipped_entries) { |
2454 | count -= per_cpu_ptr(buf->data, cpu)->skipped_entries; | |
39eaf7ef SR |
2455 | /* total is the same as the entries */ |
2456 | *total += count; | |
2457 | } else | |
2458 | *total += count + | |
12883efb | 2459 | ring_buffer_overrun_cpu(buf->buffer, cpu); |
39eaf7ef SR |
2460 | *entries += count; |
2461 | } | |
2462 | } | |
2463 | ||
e309b41d | 2464 | static void print_lat_help_header(struct seq_file *m) |
bc0c38d1 | 2465 | { |
a6168353 ME |
2466 | seq_puts(m, "# _------=> CPU# \n"); |
2467 | seq_puts(m, "# / _-----=> irqs-off \n"); | |
2468 | seq_puts(m, "# | / _----=> need-resched \n"); | |
2469 | seq_puts(m, "# || / _---=> hardirq/softirq \n"); | |
2470 | seq_puts(m, "# ||| / _--=> preempt-depth \n"); | |
e6e1e259 SR |
2471 | seq_puts(m, "# |||| / delay \n"); |
2472 | seq_puts(m, "# cmd pid ||||| time | caller \n"); | |
2473 | seq_puts(m, "# \\ / ||||| \\ | / \n"); | |
bc0c38d1 SR |
2474 | } |
2475 | ||
12883efb | 2476 | static void print_event_info(struct trace_buffer *buf, struct seq_file *m) |
bc0c38d1 | 2477 | { |
39eaf7ef SR |
2478 | unsigned long total; |
2479 | unsigned long entries; | |
2480 | ||
12883efb | 2481 | get_total_entries(buf, &total, &entries); |
39eaf7ef SR |
2482 | seq_printf(m, "# entries-in-buffer/entries-written: %lu/%lu #P:%d\n", |
2483 | entries, total, num_online_cpus()); | |
2484 | seq_puts(m, "#\n"); | |
2485 | } | |
2486 | ||
12883efb | 2487 | static void print_func_help_header(struct trace_buffer *buf, struct seq_file *m) |
39eaf7ef | 2488 | { |
12883efb | 2489 | print_event_info(buf, m); |
77271ce4 | 2490 | seq_puts(m, "# TASK-PID CPU# TIMESTAMP FUNCTION\n"); |
a6168353 | 2491 | seq_puts(m, "# | | | | |\n"); |
bc0c38d1 SR |
2492 | } |
2493 | ||
12883efb | 2494 | static void print_func_help_header_irq(struct trace_buffer *buf, struct seq_file *m) |
77271ce4 | 2495 | { |
12883efb | 2496 | print_event_info(buf, m); |
77271ce4 SR |
2497 | seq_puts(m, "# _-----=> irqs-off\n"); |
2498 | seq_puts(m, "# / _----=> need-resched\n"); | |
2499 | seq_puts(m, "# | / _---=> hardirq/softirq\n"); | |
2500 | seq_puts(m, "# || / _--=> preempt-depth\n"); | |
2501 | seq_puts(m, "# ||| / delay\n"); | |
2502 | seq_puts(m, "# TASK-PID CPU# |||| TIMESTAMP FUNCTION\n"); | |
2503 | seq_puts(m, "# | | | |||| | |\n"); | |
2504 | } | |
bc0c38d1 | 2505 | |
62b915f1 | 2506 | void |
bc0c38d1 SR |
2507 | print_trace_header(struct seq_file *m, struct trace_iterator *iter) |
2508 | { | |
2509 | unsigned long sym_flags = (trace_flags & TRACE_ITER_SYM_MASK); | |
12883efb SRRH |
2510 | struct trace_buffer *buf = iter->trace_buffer; |
2511 | struct trace_array_cpu *data = per_cpu_ptr(buf->data, buf->cpu); | |
2b6080f2 | 2512 | struct tracer *type = iter->trace; |
39eaf7ef SR |
2513 | unsigned long entries; |
2514 | unsigned long total; | |
bc0c38d1 SR |
2515 | const char *name = "preemption"; |
2516 | ||
d840f718 | 2517 | name = type->name; |
bc0c38d1 | 2518 | |
12883efb | 2519 | get_total_entries(buf, &total, &entries); |
bc0c38d1 | 2520 | |
888b55dc | 2521 | seq_printf(m, "# %s latency trace v1.1.5 on %s\n", |
bc0c38d1 | 2522 | name, UTS_RELEASE); |
888b55dc | 2523 | seq_puts(m, "# -----------------------------------" |
bc0c38d1 | 2524 | "---------------------------------\n"); |
888b55dc | 2525 | seq_printf(m, "# latency: %lu us, #%lu/%lu, CPU#%d |" |
bc0c38d1 | 2526 | " (M:%s VP:%d, KP:%d, SP:%d HP:%d", |
57f50be1 | 2527 | nsecs_to_usecs(data->saved_latency), |
bc0c38d1 | 2528 | entries, |
4c11d7ae | 2529 | total, |
12883efb | 2530 | buf->cpu, |
bc0c38d1 SR |
2531 | #if defined(CONFIG_PREEMPT_NONE) |
2532 | "server", | |
2533 | #elif defined(CONFIG_PREEMPT_VOLUNTARY) | |
2534 | "desktop", | |
b5c21b45 | 2535 | #elif defined(CONFIG_PREEMPT) |
bc0c38d1 SR |
2536 | "preempt", |
2537 | #else | |
2538 | "unknown", | |
2539 | #endif | |
2540 | /* These are reserved for later use */ | |
2541 | 0, 0, 0, 0); | |
2542 | #ifdef CONFIG_SMP | |
2543 | seq_printf(m, " #P:%d)\n", num_online_cpus()); | |
2544 | #else | |
2545 | seq_puts(m, ")\n"); | |
2546 | #endif | |
888b55dc KM |
2547 | seq_puts(m, "# -----------------\n"); |
2548 | seq_printf(m, "# | task: %.16s-%d " | |
bc0c38d1 | 2549 | "(uid:%d nice:%ld policy:%ld rt_prio:%ld)\n", |
d20b92ab EB |
2550 | data->comm, data->pid, |
2551 | from_kuid_munged(seq_user_ns(m), data->uid), data->nice, | |
bc0c38d1 | 2552 | data->policy, data->rt_priority); |
888b55dc | 2553 | seq_puts(m, "# -----------------\n"); |
bc0c38d1 SR |
2554 | |
2555 | if (data->critical_start) { | |
888b55dc | 2556 | seq_puts(m, "# => started at: "); |
214023c3 SR |
2557 | seq_print_ip_sym(&iter->seq, data->critical_start, sym_flags); |
2558 | trace_print_seq(m, &iter->seq); | |
888b55dc | 2559 | seq_puts(m, "\n# => ended at: "); |
214023c3 SR |
2560 | seq_print_ip_sym(&iter->seq, data->critical_end, sym_flags); |
2561 | trace_print_seq(m, &iter->seq); | |
8248ac05 | 2562 | seq_puts(m, "\n#\n"); |
bc0c38d1 SR |
2563 | } |
2564 | ||
888b55dc | 2565 | seq_puts(m, "#\n"); |
bc0c38d1 SR |
2566 | } |
2567 | ||
a309720c SR |
2568 | static void test_cpu_buff_start(struct trace_iterator *iter) |
2569 | { | |
2570 | struct trace_seq *s = &iter->seq; | |
2571 | ||
12ef7d44 SR |
2572 | if (!(trace_flags & TRACE_ITER_ANNOTATE)) |
2573 | return; | |
2574 | ||
2575 | if (!(iter->iter_flags & TRACE_FILE_ANNOTATE)) | |
2576 | return; | |
2577 | ||
4462344e | 2578 | if (cpumask_test_cpu(iter->cpu, iter->started)) |
a309720c SR |
2579 | return; |
2580 | ||
12883efb | 2581 | if (per_cpu_ptr(iter->trace_buffer->data, iter->cpu)->skipped_entries) |
2f26ebd5 SR |
2582 | return; |
2583 | ||
4462344e | 2584 | cpumask_set_cpu(iter->cpu, iter->started); |
b0dfa978 FW |
2585 | |
2586 | /* Don't print started cpu buffer for the first entry of the trace */ | |
2587 | if (iter->idx > 1) | |
2588 | trace_seq_printf(s, "##### CPU %u buffer started ####\n", | |
2589 | iter->cpu); | |
a309720c SR |
2590 | } |
2591 | ||
2c4f035f | 2592 | static enum print_line_t print_trace_fmt(struct trace_iterator *iter) |
bc0c38d1 | 2593 | { |
214023c3 | 2594 | struct trace_seq *s = &iter->seq; |
bc0c38d1 | 2595 | unsigned long sym_flags = (trace_flags & TRACE_ITER_SYM_MASK); |
4e3c3333 | 2596 | struct trace_entry *entry; |
f633cef0 | 2597 | struct trace_event *event; |
bc0c38d1 | 2598 | |
4e3c3333 | 2599 | entry = iter->ent; |
dd0e545f | 2600 | |
a309720c SR |
2601 | test_cpu_buff_start(iter); |
2602 | ||
c4a8e8be | 2603 | event = ftrace_find_event(entry->type); |
bc0c38d1 | 2604 | |
c4a8e8be | 2605 | if (trace_flags & TRACE_ITER_CONTEXT_INFO) { |
27d48be8 SR |
2606 | if (iter->iter_flags & TRACE_FILE_LAT_FMT) { |
2607 | if (!trace_print_lat_context(iter)) | |
2608 | goto partial; | |
2609 | } else { | |
2610 | if (!trace_print_context(iter)) | |
2611 | goto partial; | |
2612 | } | |
c4a8e8be | 2613 | } |
bc0c38d1 | 2614 | |
268ccda0 | 2615 | if (event) |
a9a57763 | 2616 | return event->funcs->trace(iter, sym_flags, event); |
d9793bd8 ACM |
2617 | |
2618 | if (!trace_seq_printf(s, "Unknown type %d\n", entry->type)) | |
2619 | goto partial; | |
02b67518 | 2620 | |
2c4f035f | 2621 | return TRACE_TYPE_HANDLED; |
d9793bd8 ACM |
2622 | partial: |
2623 | return TRACE_TYPE_PARTIAL_LINE; | |
bc0c38d1 SR |
2624 | } |
2625 | ||
2c4f035f | 2626 | static enum print_line_t print_raw_fmt(struct trace_iterator *iter) |
f9896bf3 IM |
2627 | { |
2628 | struct trace_seq *s = &iter->seq; | |
2629 | struct trace_entry *entry; | |
f633cef0 | 2630 | struct trace_event *event; |
f9896bf3 IM |
2631 | |
2632 | entry = iter->ent; | |
dd0e545f | 2633 | |
c4a8e8be | 2634 | if (trace_flags & TRACE_ITER_CONTEXT_INFO) { |
d9793bd8 ACM |
2635 | if (!trace_seq_printf(s, "%d %d %llu ", |
2636 | entry->pid, iter->cpu, iter->ts)) | |
2637 | goto partial; | |
c4a8e8be | 2638 | } |
f9896bf3 | 2639 | |
f633cef0 | 2640 | event = ftrace_find_event(entry->type); |
268ccda0 | 2641 | if (event) |
a9a57763 | 2642 | return event->funcs->raw(iter, 0, event); |
d9793bd8 ACM |
2643 | |
2644 | if (!trace_seq_printf(s, "%d ?\n", entry->type)) | |
2645 | goto partial; | |
777e208d | 2646 | |
2c4f035f | 2647 | return TRACE_TYPE_HANDLED; |
d9793bd8 ACM |
2648 | partial: |
2649 | return TRACE_TYPE_PARTIAL_LINE; | |
f9896bf3 IM |
2650 | } |
2651 | ||
2c4f035f | 2652 | static enum print_line_t print_hex_fmt(struct trace_iterator *iter) |
5e3ca0ec IM |
2653 | { |
2654 | struct trace_seq *s = &iter->seq; | |
2655 | unsigned char newline = '\n'; | |
2656 | struct trace_entry *entry; | |
f633cef0 | 2657 | struct trace_event *event; |
5e3ca0ec IM |
2658 | |
2659 | entry = iter->ent; | |
dd0e545f | 2660 | |
c4a8e8be FW |
2661 | if (trace_flags & TRACE_ITER_CONTEXT_INFO) { |
2662 | SEQ_PUT_HEX_FIELD_RET(s, entry->pid); | |
2663 | SEQ_PUT_HEX_FIELD_RET(s, iter->cpu); | |
2664 | SEQ_PUT_HEX_FIELD_RET(s, iter->ts); | |
2665 | } | |
5e3ca0ec | 2666 | |
f633cef0 | 2667 | event = ftrace_find_event(entry->type); |
268ccda0 | 2668 | if (event) { |
a9a57763 | 2669 | enum print_line_t ret = event->funcs->hex(iter, 0, event); |
d9793bd8 ACM |
2670 | if (ret != TRACE_TYPE_HANDLED) |
2671 | return ret; | |
2672 | } | |
7104f300 | 2673 | |
5e3ca0ec IM |
2674 | SEQ_PUT_FIELD_RET(s, newline); |
2675 | ||
2c4f035f | 2676 | return TRACE_TYPE_HANDLED; |
5e3ca0ec IM |
2677 | } |
2678 | ||
2c4f035f | 2679 | static enum print_line_t print_bin_fmt(struct trace_iterator *iter) |
cb0f12aa IM |
2680 | { |
2681 | struct trace_seq *s = &iter->seq; | |
2682 | struct trace_entry *entry; | |
f633cef0 | 2683 | struct trace_event *event; |
cb0f12aa IM |
2684 | |
2685 | entry = iter->ent; | |
dd0e545f | 2686 | |
c4a8e8be FW |
2687 | if (trace_flags & TRACE_ITER_CONTEXT_INFO) { |
2688 | SEQ_PUT_FIELD_RET(s, entry->pid); | |
1830b52d | 2689 | SEQ_PUT_FIELD_RET(s, iter->cpu); |
c4a8e8be FW |
2690 | SEQ_PUT_FIELD_RET(s, iter->ts); |
2691 | } | |
cb0f12aa | 2692 | |
f633cef0 | 2693 | event = ftrace_find_event(entry->type); |
a9a57763 SR |
2694 | return event ? event->funcs->binary(iter, 0, event) : |
2695 | TRACE_TYPE_HANDLED; | |
cb0f12aa IM |
2696 | } |
2697 | ||
62b915f1 | 2698 | int trace_empty(struct trace_iterator *iter) |
bc0c38d1 | 2699 | { |
6d158a81 | 2700 | struct ring_buffer_iter *buf_iter; |
bc0c38d1 SR |
2701 | int cpu; |
2702 | ||
9aba60fe | 2703 | /* If we are looking at one CPU buffer, only check that one */ |
ae3b5093 | 2704 | if (iter->cpu_file != RING_BUFFER_ALL_CPUS) { |
9aba60fe | 2705 | cpu = iter->cpu_file; |
6d158a81 SR |
2706 | buf_iter = trace_buffer_iter(iter, cpu); |
2707 | if (buf_iter) { | |
2708 | if (!ring_buffer_iter_empty(buf_iter)) | |
9aba60fe SR |
2709 | return 0; |
2710 | } else { | |
12883efb | 2711 | if (!ring_buffer_empty_cpu(iter->trace_buffer->buffer, cpu)) |
9aba60fe SR |
2712 | return 0; |
2713 | } | |
2714 | return 1; | |
2715 | } | |
2716 | ||
ab46428c | 2717 | for_each_tracing_cpu(cpu) { |
6d158a81 SR |
2718 | buf_iter = trace_buffer_iter(iter, cpu); |
2719 | if (buf_iter) { | |
2720 | if (!ring_buffer_iter_empty(buf_iter)) | |
d769041f SR |
2721 | return 0; |
2722 | } else { | |
12883efb | 2723 | if (!ring_buffer_empty_cpu(iter->trace_buffer->buffer, cpu)) |
d769041f SR |
2724 | return 0; |
2725 | } | |
bc0c38d1 | 2726 | } |
d769041f | 2727 | |
797d3712 | 2728 | return 1; |
bc0c38d1 SR |
2729 | } |
2730 | ||
4f535968 | 2731 | /* Called with trace_event_read_lock() held. */ |
955b61e5 | 2732 | enum print_line_t print_trace_line(struct trace_iterator *iter) |
f9896bf3 | 2733 | { |
2c4f035f FW |
2734 | enum print_line_t ret; |
2735 | ||
ee5e51f5 JO |
2736 | if (iter->lost_events && |
2737 | !trace_seq_printf(&iter->seq, "CPU:%d [LOST %lu EVENTS]\n", | |
2738 | iter->cpu, iter->lost_events)) | |
2739 | return TRACE_TYPE_PARTIAL_LINE; | |
bc21b478 | 2740 | |
2c4f035f FW |
2741 | if (iter->trace && iter->trace->print_line) { |
2742 | ret = iter->trace->print_line(iter); | |
2743 | if (ret != TRACE_TYPE_UNHANDLED) | |
2744 | return ret; | |
2745 | } | |
72829bc3 | 2746 | |
09ae7234 SRRH |
2747 | if (iter->ent->type == TRACE_BPUTS && |
2748 | trace_flags & TRACE_ITER_PRINTK && | |
2749 | trace_flags & TRACE_ITER_PRINTK_MSGONLY) | |
2750 | return trace_print_bputs_msg_only(iter); | |
2751 | ||
48ead020 FW |
2752 | if (iter->ent->type == TRACE_BPRINT && |
2753 | trace_flags & TRACE_ITER_PRINTK && | |
2754 | trace_flags & TRACE_ITER_PRINTK_MSGONLY) | |
5ef841f6 | 2755 | return trace_print_bprintk_msg_only(iter); |
48ead020 | 2756 | |
66896a85 FW |
2757 | if (iter->ent->type == TRACE_PRINT && |
2758 | trace_flags & TRACE_ITER_PRINTK && | |
2759 | trace_flags & TRACE_ITER_PRINTK_MSGONLY) | |
5ef841f6 | 2760 | return trace_print_printk_msg_only(iter); |
66896a85 | 2761 | |
cb0f12aa IM |
2762 | if (trace_flags & TRACE_ITER_BIN) |
2763 | return print_bin_fmt(iter); | |
2764 | ||
5e3ca0ec IM |
2765 | if (trace_flags & TRACE_ITER_HEX) |
2766 | return print_hex_fmt(iter); | |
2767 | ||
f9896bf3 IM |
2768 | if (trace_flags & TRACE_ITER_RAW) |
2769 | return print_raw_fmt(iter); | |
2770 | ||
f9896bf3 IM |
2771 | return print_trace_fmt(iter); |
2772 | } | |
2773 | ||
7e9a49ef JO |
2774 | void trace_latency_header(struct seq_file *m) |
2775 | { | |
2776 | struct trace_iterator *iter = m->private; | |
2777 | ||
2778 | /* print nothing if the buffers are empty */ | |
2779 | if (trace_empty(iter)) | |
2780 | return; | |
2781 | ||
2782 | if (iter->iter_flags & TRACE_FILE_LAT_FMT) | |
2783 | print_trace_header(m, iter); | |
2784 | ||
2785 | if (!(trace_flags & TRACE_ITER_VERBOSE)) | |
2786 | print_lat_help_header(m); | |
2787 | } | |
2788 | ||
62b915f1 JO |
2789 | void trace_default_header(struct seq_file *m) |
2790 | { | |
2791 | struct trace_iterator *iter = m->private; | |
2792 | ||
f56e7f8e JO |
2793 | if (!(trace_flags & TRACE_ITER_CONTEXT_INFO)) |
2794 | return; | |
2795 | ||
62b915f1 JO |
2796 | if (iter->iter_flags & TRACE_FILE_LAT_FMT) { |
2797 | /* print nothing if the buffers are empty */ | |
2798 | if (trace_empty(iter)) | |
2799 | return; | |
2800 | print_trace_header(m, iter); | |
2801 | if (!(trace_flags & TRACE_ITER_VERBOSE)) | |
2802 | print_lat_help_header(m); | |
2803 | } else { | |
77271ce4 SR |
2804 | if (!(trace_flags & TRACE_ITER_VERBOSE)) { |
2805 | if (trace_flags & TRACE_ITER_IRQ_INFO) | |
12883efb | 2806 | print_func_help_header_irq(iter->trace_buffer, m); |
77271ce4 | 2807 | else |
12883efb | 2808 | print_func_help_header(iter->trace_buffer, m); |
77271ce4 | 2809 | } |
62b915f1 JO |
2810 | } |
2811 | } | |
2812 | ||
e0a413f6 SR |
2813 | static void test_ftrace_alive(struct seq_file *m) |
2814 | { | |
2815 | if (!ftrace_is_dead()) | |
2816 | return; | |
2817 | seq_printf(m, "# WARNING: FUNCTION TRACING IS CORRUPTED\n"); | |
2818 | seq_printf(m, "# MAY BE MISSING FUNCTION EVENTS\n"); | |
2819 | } | |
2820 | ||
d8741e2e | 2821 | #ifdef CONFIG_TRACER_MAX_TRACE |
f1affcaa | 2822 | static void show_snapshot_main_help(struct seq_file *m) |
d8741e2e | 2823 | { |
d8741e2e SRRH |
2824 | seq_printf(m, "# echo 0 > snapshot : Clears and frees snapshot buffer\n"); |
2825 | seq_printf(m, "# echo 1 > snapshot : Allocates snapshot buffer, if not already allocated.\n"); | |
2826 | seq_printf(m, "# Takes a snapshot of the main buffer.\n"); | |
b9be6d02 | 2827 | seq_printf(m, "# echo 2 > snapshot : Clears snapshot buffer (but does not allocate or free)\n"); |
d8741e2e SRRH |
2828 | seq_printf(m, "# (Doesn't have to be '2' works with any number that\n"); |
2829 | seq_printf(m, "# is not a '0' or '1')\n"); | |
2830 | } | |
f1affcaa SRRH |
2831 | |
2832 | static void show_snapshot_percpu_help(struct seq_file *m) | |
2833 | { | |
2834 | seq_printf(m, "# echo 0 > snapshot : Invalid for per_cpu snapshot file.\n"); | |
2835 | #ifdef CONFIG_RING_BUFFER_ALLOW_SWAP | |
2836 | seq_printf(m, "# echo 1 > snapshot : Allocates snapshot buffer, if not already allocated.\n"); | |
2837 | seq_printf(m, "# Takes a snapshot of the main buffer for this cpu.\n"); | |
2838 | #else | |
2839 | seq_printf(m, "# echo 1 > snapshot : Not supported with this kernel.\n"); | |
2840 | seq_printf(m, "# Must use main snapshot file to allocate.\n"); | |
2841 | #endif | |
2842 | seq_printf(m, "# echo 2 > snapshot : Clears this cpu's snapshot buffer (but does not allocate)\n"); | |
2843 | seq_printf(m, "# (Doesn't have to be '2' works with any number that\n"); | |
2844 | seq_printf(m, "# is not a '0' or '1')\n"); | |
2845 | } | |
2846 | ||
d8741e2e SRRH |
2847 | static void print_snapshot_help(struct seq_file *m, struct trace_iterator *iter) |
2848 | { | |
45ad21ca | 2849 | if (iter->tr->allocated_snapshot) |
d8741e2e SRRH |
2850 | seq_printf(m, "#\n# * Snapshot is allocated *\n#\n"); |
2851 | else | |
2852 | seq_printf(m, "#\n# * Snapshot is freed *\n#\n"); | |
2853 | ||
2854 | seq_printf(m, "# Snapshot commands:\n"); | |
f1affcaa SRRH |
2855 | if (iter->cpu_file == RING_BUFFER_ALL_CPUS) |
2856 | show_snapshot_main_help(m); | |
2857 | else | |
2858 | show_snapshot_percpu_help(m); | |
d8741e2e SRRH |
2859 | } |
2860 | #else | |
2861 | /* Should never be called */ | |
2862 | static inline void print_snapshot_help(struct seq_file *m, struct trace_iterator *iter) { } | |
2863 | #endif | |
2864 | ||
bc0c38d1 SR |
2865 | static int s_show(struct seq_file *m, void *v) |
2866 | { | |
2867 | struct trace_iterator *iter = v; | |
a63ce5b3 | 2868 | int ret; |
bc0c38d1 SR |
2869 | |
2870 | if (iter->ent == NULL) { | |
2871 | if (iter->tr) { | |
2872 | seq_printf(m, "# tracer: %s\n", iter->trace->name); | |
2873 | seq_puts(m, "#\n"); | |
e0a413f6 | 2874 | test_ftrace_alive(m); |
bc0c38d1 | 2875 | } |
d8741e2e SRRH |
2876 | if (iter->snapshot && trace_empty(iter)) |
2877 | print_snapshot_help(m, iter); | |
2878 | else if (iter->trace && iter->trace->print_header) | |
8bba1bf5 | 2879 | iter->trace->print_header(m); |
62b915f1 JO |
2880 | else |
2881 | trace_default_header(m); | |
2882 | ||
a63ce5b3 SR |
2883 | } else if (iter->leftover) { |
2884 | /* | |
2885 | * If we filled the seq_file buffer earlier, we | |
2886 | * want to just show it now. | |
2887 | */ | |
2888 | ret = trace_print_seq(m, &iter->seq); | |
2889 | ||
2890 | /* ret should this time be zero, but you never know */ | |
2891 | iter->leftover = ret; | |
2892 | ||
bc0c38d1 | 2893 | } else { |
f9896bf3 | 2894 | print_trace_line(iter); |
a63ce5b3 SR |
2895 | ret = trace_print_seq(m, &iter->seq); |
2896 | /* | |
2897 | * If we overflow the seq_file buffer, then it will | |
2898 | * ask us for this data again at start up. | |
2899 | * Use that instead. | |
2900 | * ret is 0 if seq_file write succeeded. | |
2901 | * -1 otherwise. | |
2902 | */ | |
2903 | iter->leftover = ret; | |
bc0c38d1 SR |
2904 | } |
2905 | ||
2906 | return 0; | |
2907 | } | |
2908 | ||
649e9c70 ON |
2909 | /* |
2910 | * Should be used after trace_array_get(), trace_types_lock | |
2911 | * ensures that i_cdev was already initialized. | |
2912 | */ | |
2913 | static inline int tracing_get_cpu(struct inode *inode) | |
2914 | { | |
2915 | if (inode->i_cdev) /* See trace_create_cpu_file() */ | |
2916 | return (long)inode->i_cdev - 1; | |
2917 | return RING_BUFFER_ALL_CPUS; | |
2918 | } | |
2919 | ||
88e9d34c | 2920 | static const struct seq_operations tracer_seq_ops = { |
4bf39a94 IM |
2921 | .start = s_start, |
2922 | .next = s_next, | |
2923 | .stop = s_stop, | |
2924 | .show = s_show, | |
bc0c38d1 SR |
2925 | }; |
2926 | ||
e309b41d | 2927 | static struct trace_iterator * |
6484c71c | 2928 | __tracing_open(struct inode *inode, struct file *file, bool snapshot) |
bc0c38d1 | 2929 | { |
6484c71c | 2930 | struct trace_array *tr = inode->i_private; |
bc0c38d1 | 2931 | struct trace_iterator *iter; |
50e18b94 | 2932 | int cpu; |
bc0c38d1 | 2933 | |
85a2f9b4 SR |
2934 | if (tracing_disabled) |
2935 | return ERR_PTR(-ENODEV); | |
60a11774 | 2936 | |
50e18b94 | 2937 | iter = __seq_open_private(file, &tracer_seq_ops, sizeof(*iter)); |
85a2f9b4 SR |
2938 | if (!iter) |
2939 | return ERR_PTR(-ENOMEM); | |
bc0c38d1 | 2940 | |
6d158a81 SR |
2941 | iter->buffer_iter = kzalloc(sizeof(*iter->buffer_iter) * num_possible_cpus(), |
2942 | GFP_KERNEL); | |
93574fcc DC |
2943 | if (!iter->buffer_iter) |
2944 | goto release; | |
2945 | ||
d7350c3f FW |
2946 | /* |
2947 | * We make a copy of the current tracer to avoid concurrent | |
2948 | * changes on it while we are reading. | |
2949 | */ | |
bc0c38d1 | 2950 | mutex_lock(&trace_types_lock); |
d7350c3f | 2951 | iter->trace = kzalloc(sizeof(*iter->trace), GFP_KERNEL); |
85a2f9b4 | 2952 | if (!iter->trace) |
d7350c3f | 2953 | goto fail; |
85a2f9b4 | 2954 | |
2b6080f2 | 2955 | *iter->trace = *tr->current_trace; |
d7350c3f | 2956 | |
79f55997 | 2957 | if (!zalloc_cpumask_var(&iter->started, GFP_KERNEL)) |
b0dfa978 FW |
2958 | goto fail; |
2959 | ||
12883efb SRRH |
2960 | iter->tr = tr; |
2961 | ||
2962 | #ifdef CONFIG_TRACER_MAX_TRACE | |
2b6080f2 SR |
2963 | /* Currently only the top directory has a snapshot */ |
2964 | if (tr->current_trace->print_max || snapshot) | |
12883efb | 2965 | iter->trace_buffer = &tr->max_buffer; |
bc0c38d1 | 2966 | else |
12883efb SRRH |
2967 | #endif |
2968 | iter->trace_buffer = &tr->trace_buffer; | |
debdd57f | 2969 | iter->snapshot = snapshot; |
bc0c38d1 | 2970 | iter->pos = -1; |
6484c71c | 2971 | iter->cpu_file = tracing_get_cpu(inode); |
d7350c3f | 2972 | mutex_init(&iter->mutex); |
bc0c38d1 | 2973 | |
8bba1bf5 MM |
2974 | /* Notify the tracer early; before we stop tracing. */ |
2975 | if (iter->trace && iter->trace->open) | |
a93751ca | 2976 | iter->trace->open(iter); |
8bba1bf5 | 2977 | |
12ef7d44 | 2978 | /* Annotate start of buffers if we had overruns */ |
12883efb | 2979 | if (ring_buffer_overruns(iter->trace_buffer->buffer)) |
12ef7d44 SR |
2980 | iter->iter_flags |= TRACE_FILE_ANNOTATE; |
2981 | ||
8be0709f | 2982 | /* Output in nanoseconds only if we are using a clock in nanoseconds. */ |
58e8eedf | 2983 | if (trace_clocks[tr->clock_id].in_ns) |
8be0709f DS |
2984 | iter->iter_flags |= TRACE_FILE_TIME_IN_NS; |
2985 | ||
debdd57f HT |
2986 | /* stop the trace while dumping if we are not opening "snapshot" */ |
2987 | if (!iter->snapshot) | |
2b6080f2 | 2988 | tracing_stop_tr(tr); |
2f26ebd5 | 2989 | |
ae3b5093 | 2990 | if (iter->cpu_file == RING_BUFFER_ALL_CPUS) { |
b04cc6b1 | 2991 | for_each_tracing_cpu(cpu) { |
b04cc6b1 | 2992 | iter->buffer_iter[cpu] = |
12883efb | 2993 | ring_buffer_read_prepare(iter->trace_buffer->buffer, cpu); |
72c9ddfd DM |
2994 | } |
2995 | ring_buffer_read_prepare_sync(); | |
2996 | for_each_tracing_cpu(cpu) { | |
2997 | ring_buffer_read_start(iter->buffer_iter[cpu]); | |
2f26ebd5 | 2998 | tracing_iter_reset(iter, cpu); |
b04cc6b1 FW |
2999 | } |
3000 | } else { | |
3001 | cpu = iter->cpu_file; | |
3928a8a2 | 3002 | iter->buffer_iter[cpu] = |
12883efb | 3003 | ring_buffer_read_prepare(iter->trace_buffer->buffer, cpu); |
72c9ddfd DM |
3004 | ring_buffer_read_prepare_sync(); |
3005 | ring_buffer_read_start(iter->buffer_iter[cpu]); | |
2f26ebd5 | 3006 | tracing_iter_reset(iter, cpu); |
3928a8a2 SR |
3007 | } |
3008 | ||
bc0c38d1 SR |
3009 | mutex_unlock(&trace_types_lock); |
3010 | ||
bc0c38d1 | 3011 | return iter; |
3928a8a2 | 3012 | |
d7350c3f | 3013 | fail: |
3928a8a2 | 3014 | mutex_unlock(&trace_types_lock); |
d7350c3f | 3015 | kfree(iter->trace); |
6d158a81 | 3016 | kfree(iter->buffer_iter); |
93574fcc | 3017 | release: |
50e18b94 JO |
3018 | seq_release_private(inode, file); |
3019 | return ERR_PTR(-ENOMEM); | |
bc0c38d1 SR |
3020 | } |
3021 | ||
3022 | int tracing_open_generic(struct inode *inode, struct file *filp) | |
3023 | { | |
60a11774 SR |
3024 | if (tracing_disabled) |
3025 | return -ENODEV; | |
3026 | ||
bc0c38d1 SR |
3027 | filp->private_data = inode->i_private; |
3028 | return 0; | |
3029 | } | |
3030 | ||
2e86421d GB |
3031 | bool tracing_is_disabled(void) |
3032 | { | |
3033 | return (tracing_disabled) ? true: false; | |
3034 | } | |
3035 | ||
7b85af63 SRRH |
3036 | /* |
3037 | * Open and update trace_array ref count. | |
3038 | * Must have the current trace_array passed to it. | |
3039 | */ | |
dcc30223 | 3040 | static int tracing_open_generic_tr(struct inode *inode, struct file *filp) |
7b85af63 SRRH |
3041 | { |
3042 | struct trace_array *tr = inode->i_private; | |
3043 | ||
3044 | if (tracing_disabled) | |
3045 | return -ENODEV; | |
3046 | ||
3047 | if (trace_array_get(tr) < 0) | |
3048 | return -ENODEV; | |
3049 | ||
3050 | filp->private_data = inode->i_private; | |
3051 | ||
3052 | return 0; | |
7b85af63 SRRH |
3053 | } |
3054 | ||
4fd27358 | 3055 | static int tracing_release(struct inode *inode, struct file *file) |
bc0c38d1 | 3056 | { |
6484c71c | 3057 | struct trace_array *tr = inode->i_private; |
907f2784 | 3058 | struct seq_file *m = file->private_data; |
4acd4d00 | 3059 | struct trace_iterator *iter; |
3928a8a2 | 3060 | int cpu; |
bc0c38d1 | 3061 | |
ff451961 | 3062 | if (!(file->f_mode & FMODE_READ)) { |
6484c71c | 3063 | trace_array_put(tr); |
4acd4d00 | 3064 | return 0; |
ff451961 | 3065 | } |
4acd4d00 | 3066 | |
6484c71c | 3067 | /* Writes do not use seq_file */ |
4acd4d00 | 3068 | iter = m->private; |
bc0c38d1 | 3069 | mutex_lock(&trace_types_lock); |
a695cb58 | 3070 | |
3928a8a2 SR |
3071 | for_each_tracing_cpu(cpu) { |
3072 | if (iter->buffer_iter[cpu]) | |
3073 | ring_buffer_read_finish(iter->buffer_iter[cpu]); | |
3074 | } | |
3075 | ||
bc0c38d1 SR |
3076 | if (iter->trace && iter->trace->close) |
3077 | iter->trace->close(iter); | |
3078 | ||
debdd57f HT |
3079 | if (!iter->snapshot) |
3080 | /* reenable tracing if it was previously enabled */ | |
2b6080f2 | 3081 | tracing_start_tr(tr); |
f77d09a3 AL |
3082 | |
3083 | __trace_array_put(tr); | |
3084 | ||
bc0c38d1 SR |
3085 | mutex_unlock(&trace_types_lock); |
3086 | ||
d7350c3f | 3087 | mutex_destroy(&iter->mutex); |
b0dfa978 | 3088 | free_cpumask_var(iter->started); |
d7350c3f | 3089 | kfree(iter->trace); |
6d158a81 | 3090 | kfree(iter->buffer_iter); |
50e18b94 | 3091 | seq_release_private(inode, file); |
ff451961 | 3092 | |
bc0c38d1 SR |
3093 | return 0; |
3094 | } | |
3095 | ||
7b85af63 SRRH |
3096 | static int tracing_release_generic_tr(struct inode *inode, struct file *file) |
3097 | { | |
3098 | struct trace_array *tr = inode->i_private; | |
3099 | ||
3100 | trace_array_put(tr); | |
bc0c38d1 SR |
3101 | return 0; |
3102 | } | |
3103 | ||
7b85af63 SRRH |
3104 | static int tracing_single_release_tr(struct inode *inode, struct file *file) |
3105 | { | |
3106 | struct trace_array *tr = inode->i_private; | |
3107 | ||
3108 | trace_array_put(tr); | |
3109 | ||
3110 | return single_release(inode, file); | |
3111 | } | |
3112 | ||
bc0c38d1 SR |
3113 | static int tracing_open(struct inode *inode, struct file *file) |
3114 | { | |
6484c71c | 3115 | struct trace_array *tr = inode->i_private; |
85a2f9b4 SR |
3116 | struct trace_iterator *iter; |
3117 | int ret = 0; | |
bc0c38d1 | 3118 | |
ff451961 SRRH |
3119 | if (trace_array_get(tr) < 0) |
3120 | return -ENODEV; | |
3121 | ||
4acd4d00 | 3122 | /* If this file was open for write, then erase contents */ |
6484c71c ON |
3123 | if ((file->f_mode & FMODE_WRITE) && (file->f_flags & O_TRUNC)) { |
3124 | int cpu = tracing_get_cpu(inode); | |
3125 | ||
3126 | if (cpu == RING_BUFFER_ALL_CPUS) | |
12883efb | 3127 | tracing_reset_online_cpus(&tr->trace_buffer); |
4acd4d00 | 3128 | else |
6484c71c | 3129 | tracing_reset(&tr->trace_buffer, cpu); |
4acd4d00 | 3130 | } |
bc0c38d1 | 3131 | |
4acd4d00 | 3132 | if (file->f_mode & FMODE_READ) { |
6484c71c | 3133 | iter = __tracing_open(inode, file, false); |
4acd4d00 SR |
3134 | if (IS_ERR(iter)) |
3135 | ret = PTR_ERR(iter); | |
3136 | else if (trace_flags & TRACE_ITER_LATENCY_FMT) | |
3137 | iter->iter_flags |= TRACE_FILE_LAT_FMT; | |
3138 | } | |
ff451961 SRRH |
3139 | |
3140 | if (ret < 0) | |
3141 | trace_array_put(tr); | |
3142 | ||
bc0c38d1 SR |
3143 | return ret; |
3144 | } | |
3145 | ||
607e2ea1 SRRH |
3146 | /* |
3147 | * Some tracers are not suitable for instance buffers. | |
3148 | * A tracer is always available for the global array (toplevel) | |
3149 | * or if it explicitly states that it is. | |
3150 | */ | |
3151 | static bool | |
3152 | trace_ok_for_array(struct tracer *t, struct trace_array *tr) | |
3153 | { | |
3154 | return (tr->flags & TRACE_ARRAY_FL_GLOBAL) || t->allow_instances; | |
3155 | } | |
3156 | ||
3157 | /* Find the next tracer that this trace array may use */ | |
3158 | static struct tracer * | |
3159 | get_tracer_for_array(struct trace_array *tr, struct tracer *t) | |
3160 | { | |
3161 | while (t && !trace_ok_for_array(t, tr)) | |
3162 | t = t->next; | |
3163 | ||
3164 | return t; | |
3165 | } | |
3166 | ||
e309b41d | 3167 | static void * |
bc0c38d1 SR |
3168 | t_next(struct seq_file *m, void *v, loff_t *pos) |
3169 | { | |
607e2ea1 | 3170 | struct trace_array *tr = m->private; |
f129e965 | 3171 | struct tracer *t = v; |
bc0c38d1 SR |
3172 | |
3173 | (*pos)++; | |
3174 | ||
3175 | if (t) | |
607e2ea1 | 3176 | t = get_tracer_for_array(tr, t->next); |
bc0c38d1 | 3177 | |
bc0c38d1 SR |
3178 | return t; |
3179 | } | |
3180 | ||
3181 | static void *t_start(struct seq_file *m, loff_t *pos) | |
3182 | { | |
607e2ea1 | 3183 | struct trace_array *tr = m->private; |
f129e965 | 3184 | struct tracer *t; |
bc0c38d1 SR |
3185 | loff_t l = 0; |
3186 | ||
3187 | mutex_lock(&trace_types_lock); | |
607e2ea1 SRRH |
3188 | |
3189 | t = get_tracer_for_array(tr, trace_types); | |
3190 | for (; t && l < *pos; t = t_next(m, t, &l)) | |
3191 | ; | |
bc0c38d1 SR |
3192 | |
3193 | return t; | |
3194 | } | |
3195 | ||
3196 | static void t_stop(struct seq_file *m, void *p) | |
3197 | { | |
3198 | mutex_unlock(&trace_types_lock); | |
3199 | } | |
3200 | ||
3201 | static int t_show(struct seq_file *m, void *v) | |
3202 | { | |
3203 | struct tracer *t = v; | |
3204 | ||
3205 | if (!t) | |
3206 | return 0; | |
3207 | ||
3208 | seq_printf(m, "%s", t->name); | |
3209 | if (t->next) | |
3210 | seq_putc(m, ' '); | |
3211 | else | |
3212 | seq_putc(m, '\n'); | |
3213 | ||
3214 | return 0; | |
3215 | } | |
3216 | ||
88e9d34c | 3217 | static const struct seq_operations show_traces_seq_ops = { |
4bf39a94 IM |
3218 | .start = t_start, |
3219 | .next = t_next, | |
3220 | .stop = t_stop, | |
3221 | .show = t_show, | |
bc0c38d1 SR |
3222 | }; |
3223 | ||
3224 | static int show_traces_open(struct inode *inode, struct file *file) | |
3225 | { | |
607e2ea1 SRRH |
3226 | struct trace_array *tr = inode->i_private; |
3227 | struct seq_file *m; | |
3228 | int ret; | |
3229 | ||
60a11774 SR |
3230 | if (tracing_disabled) |
3231 | return -ENODEV; | |
3232 | ||
607e2ea1 SRRH |
3233 | ret = seq_open(file, &show_traces_seq_ops); |
3234 | if (ret) | |
3235 | return ret; | |
3236 | ||
3237 | m = file->private_data; | |
3238 | m->private = tr; | |
3239 | ||
3240 | return 0; | |
bc0c38d1 SR |
3241 | } |
3242 | ||
4acd4d00 SR |
3243 | static ssize_t |
3244 | tracing_write_stub(struct file *filp, const char __user *ubuf, | |
3245 | size_t count, loff_t *ppos) | |
3246 | { | |
3247 | return count; | |
3248 | } | |
3249 | ||
098c879e | 3250 | loff_t tracing_lseek(struct file *file, loff_t offset, int whence) |
364829b1 | 3251 | { |
098c879e SRRH |
3252 | int ret; |
3253 | ||
364829b1 | 3254 | if (file->f_mode & FMODE_READ) |
098c879e | 3255 | ret = seq_lseek(file, offset, whence); |
364829b1 | 3256 | else |
098c879e SRRH |
3257 | file->f_pos = ret = 0; |
3258 | ||
3259 | return ret; | |
364829b1 SP |
3260 | } |
3261 | ||
5e2336a0 | 3262 | static const struct file_operations tracing_fops = { |
4bf39a94 IM |
3263 | .open = tracing_open, |
3264 | .read = seq_read, | |
4acd4d00 | 3265 | .write = tracing_write_stub, |
098c879e | 3266 | .llseek = tracing_lseek, |
4bf39a94 | 3267 | .release = tracing_release, |
bc0c38d1 SR |
3268 | }; |
3269 | ||
5e2336a0 | 3270 | static const struct file_operations show_traces_fops = { |
c7078de1 IM |
3271 | .open = show_traces_open, |
3272 | .read = seq_read, | |
3273 | .release = seq_release, | |
b444786f | 3274 | .llseek = seq_lseek, |
c7078de1 IM |
3275 | }; |
3276 | ||
36dfe925 IM |
3277 | /* |
3278 | * The tracer itself will not take this lock, but still we want | |
3279 | * to provide a consistent cpumask to user-space: | |
3280 | */ | |
3281 | static DEFINE_MUTEX(tracing_cpumask_update_lock); | |
3282 | ||
3283 | /* | |
3284 | * Temporary storage for the character representation of the | |
3285 | * CPU bitmask (and one more byte for the newline): | |
3286 | */ | |
3287 | static char mask_str[NR_CPUS + 1]; | |
3288 | ||
c7078de1 IM |
3289 | static ssize_t |
3290 | tracing_cpumask_read(struct file *filp, char __user *ubuf, | |
3291 | size_t count, loff_t *ppos) | |
3292 | { | |
ccfe9e42 | 3293 | struct trace_array *tr = file_inode(filp)->i_private; |
36dfe925 | 3294 | int len; |
c7078de1 IM |
3295 | |
3296 | mutex_lock(&tracing_cpumask_update_lock); | |
36dfe925 | 3297 | |
ccfe9e42 | 3298 | len = cpumask_scnprintf(mask_str, count, tr->tracing_cpumask); |
36dfe925 IM |
3299 | if (count - len < 2) { |
3300 | count = -EINVAL; | |
3301 | goto out_err; | |
3302 | } | |
3303 | len += sprintf(mask_str + len, "\n"); | |
3304 | count = simple_read_from_buffer(ubuf, count, ppos, mask_str, NR_CPUS+1); | |
3305 | ||
3306 | out_err: | |
c7078de1 IM |
3307 | mutex_unlock(&tracing_cpumask_update_lock); |
3308 | ||
3309 | return count; | |
3310 | } | |
3311 | ||
3312 | static ssize_t | |
3313 | tracing_cpumask_write(struct file *filp, const char __user *ubuf, | |
3314 | size_t count, loff_t *ppos) | |
3315 | { | |
ccfe9e42 | 3316 | struct trace_array *tr = file_inode(filp)->i_private; |
9e01c1b7 | 3317 | cpumask_var_t tracing_cpumask_new; |
2b6080f2 | 3318 | int err, cpu; |
9e01c1b7 RR |
3319 | |
3320 | if (!alloc_cpumask_var(&tracing_cpumask_new, GFP_KERNEL)) | |
3321 | return -ENOMEM; | |
c7078de1 | 3322 | |
9e01c1b7 | 3323 | err = cpumask_parse_user(ubuf, count, tracing_cpumask_new); |
c7078de1 | 3324 | if (err) |
36dfe925 IM |
3325 | goto err_unlock; |
3326 | ||
215368e8 LZ |
3327 | mutex_lock(&tracing_cpumask_update_lock); |
3328 | ||
a5e25883 | 3329 | local_irq_disable(); |
0b9b12c1 | 3330 | arch_spin_lock(&tr->max_lock); |
ab46428c | 3331 | for_each_tracing_cpu(cpu) { |
36dfe925 IM |
3332 | /* |
3333 | * Increase/decrease the disabled counter if we are | |
3334 | * about to flip a bit in the cpumask: | |
3335 | */ | |
ccfe9e42 | 3336 | if (cpumask_test_cpu(cpu, tr->tracing_cpumask) && |
9e01c1b7 | 3337 | !cpumask_test_cpu(cpu, tracing_cpumask_new)) { |
12883efb SRRH |
3338 | atomic_inc(&per_cpu_ptr(tr->trace_buffer.data, cpu)->disabled); |
3339 | ring_buffer_record_disable_cpu(tr->trace_buffer.buffer, cpu); | |
36dfe925 | 3340 | } |
ccfe9e42 | 3341 | if (!cpumask_test_cpu(cpu, tr->tracing_cpumask) && |
9e01c1b7 | 3342 | cpumask_test_cpu(cpu, tracing_cpumask_new)) { |
12883efb SRRH |
3343 | atomic_dec(&per_cpu_ptr(tr->trace_buffer.data, cpu)->disabled); |
3344 | ring_buffer_record_enable_cpu(tr->trace_buffer.buffer, cpu); | |
36dfe925 IM |
3345 | } |
3346 | } | |
0b9b12c1 | 3347 | arch_spin_unlock(&tr->max_lock); |
a5e25883 | 3348 | local_irq_enable(); |
36dfe925 | 3349 | |
ccfe9e42 | 3350 | cpumask_copy(tr->tracing_cpumask, tracing_cpumask_new); |
36dfe925 IM |
3351 | |
3352 | mutex_unlock(&tracing_cpumask_update_lock); | |
9e01c1b7 | 3353 | free_cpumask_var(tracing_cpumask_new); |
c7078de1 IM |
3354 | |
3355 | return count; | |
36dfe925 IM |
3356 | |
3357 | err_unlock: | |
215368e8 | 3358 | free_cpumask_var(tracing_cpumask_new); |
36dfe925 IM |
3359 | |
3360 | return err; | |
c7078de1 IM |
3361 | } |
3362 | ||
5e2336a0 | 3363 | static const struct file_operations tracing_cpumask_fops = { |
ccfe9e42 | 3364 | .open = tracing_open_generic_tr, |
c7078de1 IM |
3365 | .read = tracing_cpumask_read, |
3366 | .write = tracing_cpumask_write, | |
ccfe9e42 | 3367 | .release = tracing_release_generic_tr, |
b444786f | 3368 | .llseek = generic_file_llseek, |
bc0c38d1 SR |
3369 | }; |
3370 | ||
fdb372ed | 3371 | static int tracing_trace_options_show(struct seq_file *m, void *v) |
bc0c38d1 | 3372 | { |
d8e83d26 | 3373 | struct tracer_opt *trace_opts; |
2b6080f2 | 3374 | struct trace_array *tr = m->private; |
d8e83d26 | 3375 | u32 tracer_flags; |
d8e83d26 | 3376 | int i; |
adf9f195 | 3377 | |
d8e83d26 | 3378 | mutex_lock(&trace_types_lock); |
2b6080f2 SR |
3379 | tracer_flags = tr->current_trace->flags->val; |
3380 | trace_opts = tr->current_trace->flags->opts; | |
d8e83d26 | 3381 | |
bc0c38d1 SR |
3382 | for (i = 0; trace_options[i]; i++) { |
3383 | if (trace_flags & (1 << i)) | |
fdb372ed | 3384 | seq_printf(m, "%s\n", trace_options[i]); |
bc0c38d1 | 3385 | else |
fdb372ed | 3386 | seq_printf(m, "no%s\n", trace_options[i]); |
bc0c38d1 SR |
3387 | } |
3388 | ||
adf9f195 FW |
3389 | for (i = 0; trace_opts[i].name; i++) { |
3390 | if (tracer_flags & trace_opts[i].bit) | |
fdb372ed | 3391 | seq_printf(m, "%s\n", trace_opts[i].name); |
adf9f195 | 3392 | else |
fdb372ed | 3393 | seq_printf(m, "no%s\n", trace_opts[i].name); |
adf9f195 | 3394 | } |
d8e83d26 | 3395 | mutex_unlock(&trace_types_lock); |
adf9f195 | 3396 | |
fdb372ed | 3397 | return 0; |
bc0c38d1 | 3398 | } |
bc0c38d1 | 3399 | |
8c1a49ae | 3400 | static int __set_tracer_option(struct trace_array *tr, |
8d18eaaf LZ |
3401 | struct tracer_flags *tracer_flags, |
3402 | struct tracer_opt *opts, int neg) | |
3403 | { | |
8c1a49ae | 3404 | struct tracer *trace = tr->current_trace; |
8d18eaaf | 3405 | int ret; |
bc0c38d1 | 3406 | |
8c1a49ae | 3407 | ret = trace->set_flag(tr, tracer_flags->val, opts->bit, !neg); |
8d18eaaf LZ |
3408 | if (ret) |
3409 | return ret; | |
3410 | ||
3411 | if (neg) | |
3412 | tracer_flags->val &= ~opts->bit; | |
3413 | else | |
3414 | tracer_flags->val |= opts->bit; | |
3415 | return 0; | |
bc0c38d1 SR |
3416 | } |
3417 | ||
adf9f195 | 3418 | /* Try to assign a tracer specific option */ |
8c1a49ae | 3419 | static int set_tracer_option(struct trace_array *tr, char *cmp, int neg) |
adf9f195 | 3420 | { |
8c1a49ae | 3421 | struct tracer *trace = tr->current_trace; |
7770841e | 3422 | struct tracer_flags *tracer_flags = trace->flags; |
adf9f195 | 3423 | struct tracer_opt *opts = NULL; |
8d18eaaf | 3424 | int i; |
adf9f195 | 3425 | |
7770841e Z |
3426 | for (i = 0; tracer_flags->opts[i].name; i++) { |
3427 | opts = &tracer_flags->opts[i]; | |
adf9f195 | 3428 | |
8d18eaaf | 3429 | if (strcmp(cmp, opts->name) == 0) |
8c1a49ae | 3430 | return __set_tracer_option(tr, trace->flags, opts, neg); |
adf9f195 | 3431 | } |
adf9f195 | 3432 | |
8d18eaaf | 3433 | return -EINVAL; |
adf9f195 FW |
3434 | } |
3435 | ||
613f04a0 SRRH |
3436 | /* Some tracers require overwrite to stay enabled */ |
3437 | int trace_keep_overwrite(struct tracer *tracer, u32 mask, int set) | |
3438 | { | |
3439 | if (tracer->enabled && (mask & TRACE_ITER_OVERWRITE) && !set) | |
3440 | return -1; | |
3441 | ||
3442 | return 0; | |
3443 | } | |
3444 | ||
2b6080f2 | 3445 | int set_tracer_flag(struct trace_array *tr, unsigned int mask, int enabled) |
af4617bd SR |
3446 | { |
3447 | /* do nothing if flag is already set */ | |
3448 | if (!!(trace_flags & mask) == !!enabled) | |
613f04a0 SRRH |
3449 | return 0; |
3450 | ||
3451 | /* Give the tracer a chance to approve the change */ | |
2b6080f2 | 3452 | if (tr->current_trace->flag_changed) |
bf6065b5 | 3453 | if (tr->current_trace->flag_changed(tr, mask, !!enabled)) |
613f04a0 | 3454 | return -EINVAL; |
af4617bd SR |
3455 | |
3456 | if (enabled) | |
3457 | trace_flags |= mask; | |
3458 | else | |
3459 | trace_flags &= ~mask; | |
e870e9a1 LZ |
3460 | |
3461 | if (mask == TRACE_ITER_RECORD_CMD) | |
3462 | trace_event_enable_cmd_record(enabled); | |
750912fa | 3463 | |
80902822 | 3464 | if (mask == TRACE_ITER_OVERWRITE) { |
12883efb | 3465 | ring_buffer_change_overwrite(tr->trace_buffer.buffer, enabled); |
80902822 | 3466 | #ifdef CONFIG_TRACER_MAX_TRACE |
12883efb | 3467 | ring_buffer_change_overwrite(tr->max_buffer.buffer, enabled); |
80902822 SRRH |
3468 | #endif |
3469 | } | |
81698831 SR |
3470 | |
3471 | if (mask == TRACE_ITER_PRINTK) | |
3472 | trace_printk_start_stop_comm(enabled); | |
613f04a0 SRRH |
3473 | |
3474 | return 0; | |
af4617bd SR |
3475 | } |
3476 | ||
2b6080f2 | 3477 | static int trace_set_options(struct trace_array *tr, char *option) |
bc0c38d1 | 3478 | { |
8d18eaaf | 3479 | char *cmp; |
bc0c38d1 | 3480 | int neg = 0; |
613f04a0 | 3481 | int ret = -ENODEV; |
bc0c38d1 SR |
3482 | int i; |
3483 | ||
7bcfaf54 | 3484 | cmp = strstrip(option); |
bc0c38d1 | 3485 | |
8d18eaaf | 3486 | if (strncmp(cmp, "no", 2) == 0) { |
bc0c38d1 SR |
3487 | neg = 1; |
3488 | cmp += 2; | |
3489 | } | |
3490 | ||
69d34da2 SRRH |
3491 | mutex_lock(&trace_types_lock); |
3492 | ||
bc0c38d1 | 3493 | for (i = 0; trace_options[i]; i++) { |
8d18eaaf | 3494 | if (strcmp(cmp, trace_options[i]) == 0) { |
2b6080f2 | 3495 | ret = set_tracer_flag(tr, 1 << i, !neg); |
bc0c38d1 SR |
3496 | break; |
3497 | } | |
3498 | } | |
adf9f195 FW |
3499 | |
3500 | /* If no option could be set, test the specific tracer options */ | |
69d34da2 | 3501 | if (!trace_options[i]) |
8c1a49ae | 3502 | ret = set_tracer_option(tr, cmp, neg); |
69d34da2 SRRH |
3503 | |
3504 | mutex_unlock(&trace_types_lock); | |
bc0c38d1 | 3505 | |
7bcfaf54 SR |
3506 | return ret; |
3507 | } | |
3508 | ||
3509 | static ssize_t | |
3510 | tracing_trace_options_write(struct file *filp, const char __user *ubuf, | |
3511 | size_t cnt, loff_t *ppos) | |
3512 | { | |
2b6080f2 SR |
3513 | struct seq_file *m = filp->private_data; |
3514 | struct trace_array *tr = m->private; | |
7bcfaf54 | 3515 | char buf[64]; |
613f04a0 | 3516 | int ret; |
7bcfaf54 SR |
3517 | |
3518 | if (cnt >= sizeof(buf)) | |
3519 | return -EINVAL; | |
3520 | ||
3521 | if (copy_from_user(&buf, ubuf, cnt)) | |
3522 | return -EFAULT; | |
3523 | ||
a8dd2176 SR |
3524 | buf[cnt] = 0; |
3525 | ||
2b6080f2 | 3526 | ret = trace_set_options(tr, buf); |
613f04a0 SRRH |
3527 | if (ret < 0) |
3528 | return ret; | |
7bcfaf54 | 3529 | |
cf8517cf | 3530 | *ppos += cnt; |
bc0c38d1 SR |
3531 | |
3532 | return cnt; | |
3533 | } | |
3534 | ||
fdb372ed LZ |
3535 | static int tracing_trace_options_open(struct inode *inode, struct file *file) |
3536 | { | |
7b85af63 | 3537 | struct trace_array *tr = inode->i_private; |
f77d09a3 | 3538 | int ret; |
7b85af63 | 3539 | |
fdb372ed LZ |
3540 | if (tracing_disabled) |
3541 | return -ENODEV; | |
2b6080f2 | 3542 | |
7b85af63 SRRH |
3543 | if (trace_array_get(tr) < 0) |
3544 | return -ENODEV; | |
3545 | ||
f77d09a3 AL |
3546 | ret = single_open(file, tracing_trace_options_show, inode->i_private); |
3547 | if (ret < 0) | |
3548 | trace_array_put(tr); | |
3549 | ||
3550 | return ret; | |
fdb372ed LZ |
3551 | } |
3552 | ||
5e2336a0 | 3553 | static const struct file_operations tracing_iter_fops = { |
fdb372ed LZ |
3554 | .open = tracing_trace_options_open, |
3555 | .read = seq_read, | |
3556 | .llseek = seq_lseek, | |
7b85af63 | 3557 | .release = tracing_single_release_tr, |
ee6bce52 | 3558 | .write = tracing_trace_options_write, |
bc0c38d1 SR |
3559 | }; |
3560 | ||
7bd2f24c IM |
3561 | static const char readme_msg[] = |
3562 | "tracing mini-HOWTO:\n\n" | |
22f45649 SRRH |
3563 | "# echo 0 > tracing_on : quick way to disable tracing\n" |
3564 | "# echo 1 > tracing_on : quick way to re-enable tracing\n\n" | |
3565 | " Important files:\n" | |
3566 | " trace\t\t\t- The static contents of the buffer\n" | |
3567 | "\t\t\t To clear the buffer write into this file: echo > trace\n" | |
3568 | " trace_pipe\t\t- A consuming read to see the contents of the buffer\n" | |
3569 | " current_tracer\t- function and latency tracers\n" | |
3570 | " available_tracers\t- list of configured tracers for current_tracer\n" | |
3571 | " buffer_size_kb\t- view and modify size of per cpu buffer\n" | |
3572 | " buffer_total_size_kb - view total size of all cpu buffers\n\n" | |
3573 | " trace_clock\t\t-change the clock used to order events\n" | |
3574 | " local: Per cpu clock but may not be synced across CPUs\n" | |
3575 | " global: Synced across CPUs but slows tracing down.\n" | |
3576 | " counter: Not a clock, but just an increment\n" | |
3577 | " uptime: Jiffy counter from time of boot\n" | |
3578 | " perf: Same clock that perf events use\n" | |
3579 | #ifdef CONFIG_X86_64 | |
3580 | " x86-tsc: TSC cycle counter\n" | |
3581 | #endif | |
3582 | "\n trace_marker\t\t- Writes into this file writes into the kernel buffer\n" | |
3583 | " tracing_cpumask\t- Limit which CPUs to trace\n" | |
3584 | " instances\t\t- Make sub-buffers with: mkdir instances/foo\n" | |
3585 | "\t\t\t Remove sub-buffer with rmdir\n" | |
3586 | " trace_options\t\t- Set format or modify how tracing happens\n" | |
71485c45 SRRH |
3587 | "\t\t\t Disable an option by adding a suffix 'no' to the\n" |
3588 | "\t\t\t option name\n" | |
22f45649 SRRH |
3589 | #ifdef CONFIG_DYNAMIC_FTRACE |
3590 | "\n available_filter_functions - list of functions that can be filtered on\n" | |
71485c45 SRRH |
3591 | " set_ftrace_filter\t- echo function name in here to only trace these\n" |
3592 | "\t\t\t functions\n" | |
3593 | "\t accepts: func_full_name, *func_end, func_begin*, *func_middle*\n" | |
3594 | "\t modules: Can select a group via module\n" | |
3595 | "\t Format: :mod:<module-name>\n" | |
3596 | "\t example: echo :mod:ext3 > set_ftrace_filter\n" | |
3597 | "\t triggers: a command to perform when function is hit\n" | |
3598 | "\t Format: <function>:<trigger>[:count]\n" | |
3599 | "\t trigger: traceon, traceoff\n" | |
3600 | "\t\t enable_event:<system>:<event>\n" | |
3601 | "\t\t disable_event:<system>:<event>\n" | |
22f45649 | 3602 | #ifdef CONFIG_STACKTRACE |
71485c45 | 3603 | "\t\t stacktrace\n" |
22f45649 SRRH |
3604 | #endif |
3605 | #ifdef CONFIG_TRACER_SNAPSHOT | |
71485c45 | 3606 | "\t\t snapshot\n" |
22f45649 | 3607 | #endif |
17a280ea SRRH |
3608 | "\t\t dump\n" |
3609 | "\t\t cpudump\n" | |
71485c45 SRRH |
3610 | "\t example: echo do_fault:traceoff > set_ftrace_filter\n" |
3611 | "\t echo do_trap:traceoff:3 > set_ftrace_filter\n" | |
3612 | "\t The first one will disable tracing every time do_fault is hit\n" | |
3613 | "\t The second will disable tracing at most 3 times when do_trap is hit\n" | |
3614 | "\t The first time do trap is hit and it disables tracing, the\n" | |
3615 | "\t counter will decrement to 2. If tracing is already disabled,\n" | |
3616 | "\t the counter will not decrement. It only decrements when the\n" | |
3617 | "\t trigger did work\n" | |
3618 | "\t To remove trigger without count:\n" | |
3619 | "\t echo '!<function>:<trigger> > set_ftrace_filter\n" | |
3620 | "\t To remove trigger with a count:\n" | |
3621 | "\t echo '!<function>:<trigger>:0 > set_ftrace_filter\n" | |
22f45649 | 3622 | " set_ftrace_notrace\t- echo function name in here to never trace.\n" |
71485c45 SRRH |
3623 | "\t accepts: func_full_name, *func_end, func_begin*, *func_middle*\n" |
3624 | "\t modules: Can select a group via module command :mod:\n" | |
3625 | "\t Does not accept triggers\n" | |
22f45649 SRRH |
3626 | #endif /* CONFIG_DYNAMIC_FTRACE */ |
3627 | #ifdef CONFIG_FUNCTION_TRACER | |
71485c45 SRRH |
3628 | " set_ftrace_pid\t- Write pid(s) to only function trace those pids\n" |
3629 | "\t\t (function)\n" | |
22f45649 SRRH |
3630 | #endif |
3631 | #ifdef CONFIG_FUNCTION_GRAPH_TRACER | |
3632 | " set_graph_function\t- Trace the nested calls of a function (function_graph)\n" | |
3633 | " max_graph_depth\t- Trace a limited depth of nested calls (0 is unlimited)\n" | |
3634 | #endif | |
3635 | #ifdef CONFIG_TRACER_SNAPSHOT | |
71485c45 SRRH |
3636 | "\n snapshot\t\t- Like 'trace' but shows the content of the static\n" |
3637 | "\t\t\t snapshot buffer. Read the contents for more\n" | |
3638 | "\t\t\t information\n" | |
22f45649 | 3639 | #endif |
991821c8 | 3640 | #ifdef CONFIG_STACK_TRACER |
22f45649 SRRH |
3641 | " stack_trace\t\t- Shows the max stack trace when active\n" |
3642 | " stack_max_size\t- Shows current max stack size that was traced\n" | |
71485c45 SRRH |
3643 | "\t\t\t Write into this file to reset the max size (trigger a\n" |
3644 | "\t\t\t new trace)\n" | |
22f45649 | 3645 | #ifdef CONFIG_DYNAMIC_FTRACE |
71485c45 SRRH |
3646 | " stack_trace_filter\t- Like set_ftrace_filter but limits what stack_trace\n" |
3647 | "\t\t\t traces\n" | |
22f45649 | 3648 | #endif |
991821c8 | 3649 | #endif /* CONFIG_STACK_TRACER */ |
26f25564 TZ |
3650 | " events/\t\t- Directory containing all trace event subsystems:\n" |
3651 | " enable\t\t- Write 0/1 to enable/disable tracing of all events\n" | |
3652 | " events/<system>/\t- Directory containing all trace events for <system>:\n" | |
71485c45 SRRH |
3653 | " enable\t\t- Write 0/1 to enable/disable tracing of all <system>\n" |
3654 | "\t\t\t events\n" | |
26f25564 | 3655 | " filter\t\t- If set, only events passing filter are traced\n" |
71485c45 SRRH |
3656 | " events/<system>/<event>/\t- Directory containing control files for\n" |
3657 | "\t\t\t <event>:\n" | |
26f25564 TZ |
3658 | " enable\t\t- Write 0/1 to enable/disable tracing of <event>\n" |
3659 | " filter\t\t- If set, only events passing filter are traced\n" | |
3660 | " trigger\t\t- If set, a command to perform when event is hit\n" | |
71485c45 SRRH |
3661 | "\t Format: <trigger>[:count][if <filter>]\n" |
3662 | "\t trigger: traceon, traceoff\n" | |
3663 | "\t enable_event:<system>:<event>\n" | |
3664 | "\t disable_event:<system>:<event>\n" | |
26f25564 | 3665 | #ifdef CONFIG_STACKTRACE |
71485c45 | 3666 | "\t\t stacktrace\n" |
26f25564 TZ |
3667 | #endif |
3668 | #ifdef CONFIG_TRACER_SNAPSHOT | |
71485c45 | 3669 | "\t\t snapshot\n" |
26f25564 | 3670 | #endif |
71485c45 SRRH |
3671 | "\t example: echo traceoff > events/block/block_unplug/trigger\n" |
3672 | "\t echo traceoff:3 > events/block/block_unplug/trigger\n" | |
3673 | "\t echo 'enable_event:kmem:kmalloc:3 if nr_rq > 1' > \\\n" | |
3674 | "\t events/block/block_unplug/trigger\n" | |
3675 | "\t The first disables tracing every time block_unplug is hit.\n" | |
3676 | "\t The second disables tracing the first 3 times block_unplug is hit.\n" | |
3677 | "\t The third enables the kmalloc event the first 3 times block_unplug\n" | |
3678 | "\t is hit and has value of greater than 1 for the 'nr_rq' event field.\n" | |
3679 | "\t Like function triggers, the counter is only decremented if it\n" | |
3680 | "\t enabled or disabled tracing.\n" | |
3681 | "\t To remove a trigger without a count:\n" | |
3682 | "\t echo '!<trigger> > <system>/<event>/trigger\n" | |
3683 | "\t To remove a trigger with a count:\n" | |
3684 | "\t echo '!<trigger>:0 > <system>/<event>/trigger\n" | |
3685 | "\t Filters can be ignored when removing a trigger.\n" | |
7bd2f24c IM |
3686 | ; |
3687 | ||
3688 | static ssize_t | |
3689 | tracing_readme_read(struct file *filp, char __user *ubuf, | |
3690 | size_t cnt, loff_t *ppos) | |
3691 | { | |
3692 | return simple_read_from_buffer(ubuf, cnt, ppos, | |
3693 | readme_msg, strlen(readme_msg)); | |
3694 | } | |
3695 | ||
5e2336a0 | 3696 | static const struct file_operations tracing_readme_fops = { |
c7078de1 IM |
3697 | .open = tracing_open_generic, |
3698 | .read = tracing_readme_read, | |
b444786f | 3699 | .llseek = generic_file_llseek, |
7bd2f24c IM |
3700 | }; |
3701 | ||
42584c81 YY |
3702 | static void *saved_cmdlines_next(struct seq_file *m, void *v, loff_t *pos) |
3703 | { | |
3704 | unsigned int *ptr = v; | |
69abe6a5 | 3705 | |
42584c81 YY |
3706 | if (*pos || m->count) |
3707 | ptr++; | |
69abe6a5 | 3708 | |
42584c81 | 3709 | (*pos)++; |
69abe6a5 | 3710 | |
42584c81 YY |
3711 | for (; ptr < &map_cmdline_to_pid[SAVED_CMDLINES]; ptr++) { |
3712 | if (*ptr == -1 || *ptr == NO_CMDLINE_MAP) | |
3713 | continue; | |
69abe6a5 | 3714 | |
42584c81 YY |
3715 | return ptr; |
3716 | } | |
69abe6a5 | 3717 | |
42584c81 YY |
3718 | return NULL; |
3719 | } | |
3720 | ||
3721 | static void *saved_cmdlines_start(struct seq_file *m, loff_t *pos) | |
3722 | { | |
3723 | void *v; | |
3724 | loff_t l = 0; | |
69abe6a5 | 3725 | |
42584c81 YY |
3726 | v = &map_cmdline_to_pid[0]; |
3727 | while (l <= *pos) { | |
3728 | v = saved_cmdlines_next(m, v, &l); | |
3729 | if (!v) | |
3730 | return NULL; | |
69abe6a5 AP |
3731 | } |
3732 | ||
42584c81 YY |
3733 | return v; |
3734 | } | |
3735 | ||
3736 | static void saved_cmdlines_stop(struct seq_file *m, void *v) | |
3737 | { | |
3738 | } | |
69abe6a5 | 3739 | |
42584c81 YY |
3740 | static int saved_cmdlines_show(struct seq_file *m, void *v) |
3741 | { | |
3742 | char buf[TASK_COMM_LEN]; | |
3743 | unsigned int *pid = v; | |
69abe6a5 | 3744 | |
42584c81 YY |
3745 | trace_find_cmdline(*pid, buf); |
3746 | seq_printf(m, "%d %s\n", *pid, buf); | |
3747 | return 0; | |
3748 | } | |
3749 | ||
3750 | static const struct seq_operations tracing_saved_cmdlines_seq_ops = { | |
3751 | .start = saved_cmdlines_start, | |
3752 | .next = saved_cmdlines_next, | |
3753 | .stop = saved_cmdlines_stop, | |
3754 | .show = saved_cmdlines_show, | |
3755 | }; | |
3756 | ||
3757 | static int tracing_saved_cmdlines_open(struct inode *inode, struct file *filp) | |
3758 | { | |
3759 | if (tracing_disabled) | |
3760 | return -ENODEV; | |
3761 | ||
3762 | return seq_open(filp, &tracing_saved_cmdlines_seq_ops); | |
69abe6a5 AP |
3763 | } |
3764 | ||
3765 | static const struct file_operations tracing_saved_cmdlines_fops = { | |
42584c81 YY |
3766 | .open = tracing_saved_cmdlines_open, |
3767 | .read = seq_read, | |
3768 | .llseek = seq_lseek, | |
3769 | .release = seq_release, | |
69abe6a5 AP |
3770 | }; |
3771 | ||
bc0c38d1 SR |
3772 | static ssize_t |
3773 | tracing_set_trace_read(struct file *filp, char __user *ubuf, | |
3774 | size_t cnt, loff_t *ppos) | |
3775 | { | |
2b6080f2 | 3776 | struct trace_array *tr = filp->private_data; |
ee6c2c1b | 3777 | char buf[MAX_TRACER_SIZE+2]; |
bc0c38d1 SR |
3778 | int r; |
3779 | ||
3780 | mutex_lock(&trace_types_lock); | |
2b6080f2 | 3781 | r = sprintf(buf, "%s\n", tr->current_trace->name); |
bc0c38d1 SR |
3782 | mutex_unlock(&trace_types_lock); |
3783 | ||
4bf39a94 | 3784 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, r); |
bc0c38d1 SR |
3785 | } |
3786 | ||
b6f11df2 ACM |
3787 | int tracer_init(struct tracer *t, struct trace_array *tr) |
3788 | { | |
12883efb | 3789 | tracing_reset_online_cpus(&tr->trace_buffer); |
b6f11df2 ACM |
3790 | return t->init(tr); |
3791 | } | |
3792 | ||
12883efb | 3793 | static void set_buffer_entries(struct trace_buffer *buf, unsigned long val) |
438ced17 VN |
3794 | { |
3795 | int cpu; | |
737223fb | 3796 | |
438ced17 | 3797 | for_each_tracing_cpu(cpu) |
12883efb | 3798 | per_cpu_ptr(buf->data, cpu)->entries = val; |
438ced17 VN |
3799 | } |
3800 | ||
12883efb | 3801 | #ifdef CONFIG_TRACER_MAX_TRACE |
d60da506 | 3802 | /* resize @tr's buffer to the size of @size_tr's entries */ |
12883efb SRRH |
3803 | static int resize_buffer_duplicate_size(struct trace_buffer *trace_buf, |
3804 | struct trace_buffer *size_buf, int cpu_id) | |
d60da506 HT |
3805 | { |
3806 | int cpu, ret = 0; | |
3807 | ||
3808 | if (cpu_id == RING_BUFFER_ALL_CPUS) { | |
3809 | for_each_tracing_cpu(cpu) { | |
12883efb SRRH |
3810 | ret = ring_buffer_resize(trace_buf->buffer, |
3811 | per_cpu_ptr(size_buf->data, cpu)->entries, cpu); | |
d60da506 HT |
3812 | if (ret < 0) |
3813 | break; | |
12883efb SRRH |
3814 | per_cpu_ptr(trace_buf->data, cpu)->entries = |
3815 | per_cpu_ptr(size_buf->data, cpu)->entries; | |
d60da506 HT |
3816 | } |
3817 | } else { | |
12883efb SRRH |
3818 | ret = ring_buffer_resize(trace_buf->buffer, |
3819 | per_cpu_ptr(size_buf->data, cpu_id)->entries, cpu_id); | |
d60da506 | 3820 | if (ret == 0) |
12883efb SRRH |
3821 | per_cpu_ptr(trace_buf->data, cpu_id)->entries = |
3822 | per_cpu_ptr(size_buf->data, cpu_id)->entries; | |
d60da506 HT |
3823 | } |
3824 | ||
3825 | return ret; | |
3826 | } | |
12883efb | 3827 | #endif /* CONFIG_TRACER_MAX_TRACE */ |
d60da506 | 3828 | |
2b6080f2 SR |
3829 | static int __tracing_resize_ring_buffer(struct trace_array *tr, |
3830 | unsigned long size, int cpu) | |
73c5162a SR |
3831 | { |
3832 | int ret; | |
3833 | ||
3834 | /* | |
3835 | * If kernel or user changes the size of the ring buffer | |
a123c52b SR |
3836 | * we use the size that was given, and we can forget about |
3837 | * expanding it later. | |
73c5162a | 3838 | */ |
55034cd6 | 3839 | ring_buffer_expanded = true; |
73c5162a | 3840 | |
b382ede6 | 3841 | /* May be called before buffers are initialized */ |
12883efb | 3842 | if (!tr->trace_buffer.buffer) |
b382ede6 SR |
3843 | return 0; |
3844 | ||
12883efb | 3845 | ret = ring_buffer_resize(tr->trace_buffer.buffer, size, cpu); |
73c5162a SR |
3846 | if (ret < 0) |
3847 | return ret; | |
3848 | ||
12883efb | 3849 | #ifdef CONFIG_TRACER_MAX_TRACE |
2b6080f2 SR |
3850 | if (!(tr->flags & TRACE_ARRAY_FL_GLOBAL) || |
3851 | !tr->current_trace->use_max_tr) | |
ef710e10 KM |
3852 | goto out; |
3853 | ||
12883efb | 3854 | ret = ring_buffer_resize(tr->max_buffer.buffer, size, cpu); |
73c5162a | 3855 | if (ret < 0) { |
12883efb SRRH |
3856 | int r = resize_buffer_duplicate_size(&tr->trace_buffer, |
3857 | &tr->trace_buffer, cpu); | |
73c5162a | 3858 | if (r < 0) { |
a123c52b SR |
3859 | /* |
3860 | * AARGH! We are left with different | |
3861 | * size max buffer!!!! | |
3862 | * The max buffer is our "snapshot" buffer. | |
3863 | * When a tracer needs a snapshot (one of the | |
3864 | * latency tracers), it swaps the max buffer | |
3865 | * with the saved snap shot. We succeeded to | |
3866 | * update the size of the main buffer, but failed to | |
3867 | * update the size of the max buffer. But when we tried | |
3868 | * to reset the main buffer to the original size, we | |
3869 | * failed there too. This is very unlikely to | |
3870 | * happen, but if it does, warn and kill all | |
3871 | * tracing. | |
3872 | */ | |
73c5162a SR |
3873 | WARN_ON(1); |
3874 | tracing_disabled = 1; | |
3875 | } | |
3876 | return ret; | |
3877 | } | |
3878 | ||
438ced17 | 3879 | if (cpu == RING_BUFFER_ALL_CPUS) |
12883efb | 3880 | set_buffer_entries(&tr->max_buffer, size); |
438ced17 | 3881 | else |
12883efb | 3882 | per_cpu_ptr(tr->max_buffer.data, cpu)->entries = size; |
438ced17 | 3883 | |
ef710e10 | 3884 | out: |
12883efb SRRH |
3885 | #endif /* CONFIG_TRACER_MAX_TRACE */ |
3886 | ||
438ced17 | 3887 | if (cpu == RING_BUFFER_ALL_CPUS) |
12883efb | 3888 | set_buffer_entries(&tr->trace_buffer, size); |
438ced17 | 3889 | else |
12883efb | 3890 | per_cpu_ptr(tr->trace_buffer.data, cpu)->entries = size; |
73c5162a SR |
3891 | |
3892 | return ret; | |
3893 | } | |
3894 | ||
2b6080f2 SR |
3895 | static ssize_t tracing_resize_ring_buffer(struct trace_array *tr, |
3896 | unsigned long size, int cpu_id) | |
4f271a2a | 3897 | { |
83f40318 | 3898 | int ret = size; |
4f271a2a VN |
3899 | |
3900 | mutex_lock(&trace_types_lock); | |
3901 | ||
438ced17 VN |
3902 | if (cpu_id != RING_BUFFER_ALL_CPUS) { |
3903 | /* make sure, this cpu is enabled in the mask */ | |
3904 | if (!cpumask_test_cpu(cpu_id, tracing_buffer_mask)) { | |
3905 | ret = -EINVAL; | |
3906 | goto out; | |
3907 | } | |
3908 | } | |
4f271a2a | 3909 | |
2b6080f2 | 3910 | ret = __tracing_resize_ring_buffer(tr, size, cpu_id); |
4f271a2a VN |
3911 | if (ret < 0) |
3912 | ret = -ENOMEM; | |
3913 | ||
438ced17 | 3914 | out: |
4f271a2a VN |
3915 | mutex_unlock(&trace_types_lock); |
3916 | ||
3917 | return ret; | |
3918 | } | |
3919 | ||
ef710e10 | 3920 | |
1852fcce SR |
3921 | /** |
3922 | * tracing_update_buffers - used by tracing facility to expand ring buffers | |
3923 | * | |
3924 | * To save on memory when the tracing is never used on a system with it | |
3925 | * configured in. The ring buffers are set to a minimum size. But once | |
3926 | * a user starts to use the tracing facility, then they need to grow | |
3927 | * to their default size. | |
3928 | * | |
3929 | * This function is to be called when a tracer is about to be used. | |
3930 | */ | |
3931 | int tracing_update_buffers(void) | |
3932 | { | |
3933 | int ret = 0; | |
3934 | ||
1027fcb2 | 3935 | mutex_lock(&trace_types_lock); |
1852fcce | 3936 | if (!ring_buffer_expanded) |
2b6080f2 | 3937 | ret = __tracing_resize_ring_buffer(&global_trace, trace_buf_size, |
438ced17 | 3938 | RING_BUFFER_ALL_CPUS); |
1027fcb2 | 3939 | mutex_unlock(&trace_types_lock); |
1852fcce SR |
3940 | |
3941 | return ret; | |
3942 | } | |
3943 | ||
577b785f SR |
3944 | struct trace_option_dentry; |
3945 | ||
3946 | static struct trace_option_dentry * | |
2b6080f2 | 3947 | create_trace_option_files(struct trace_array *tr, struct tracer *tracer); |
577b785f SR |
3948 | |
3949 | static void | |
3950 | destroy_trace_option_files(struct trace_option_dentry *topts); | |
3951 | ||
6b450d25 SRRH |
3952 | /* |
3953 | * Used to clear out the tracer before deletion of an instance. | |
3954 | * Must have trace_types_lock held. | |
3955 | */ | |
3956 | static void tracing_set_nop(struct trace_array *tr) | |
3957 | { | |
3958 | if (tr->current_trace == &nop_trace) | |
3959 | return; | |
3960 | ||
50512ab5 | 3961 | tr->current_trace->enabled--; |
6b450d25 SRRH |
3962 | |
3963 | if (tr->current_trace->reset) | |
3964 | tr->current_trace->reset(tr); | |
3965 | ||
3966 | tr->current_trace = &nop_trace; | |
3967 | } | |
3968 | ||
607e2ea1 | 3969 | static int tracing_set_tracer(struct trace_array *tr, const char *buf) |
bc0c38d1 | 3970 | { |
577b785f | 3971 | static struct trace_option_dentry *topts; |
bc0c38d1 | 3972 | struct tracer *t; |
12883efb | 3973 | #ifdef CONFIG_TRACER_MAX_TRACE |
34600f0e | 3974 | bool had_max_tr; |
12883efb | 3975 | #endif |
d9e54076 | 3976 | int ret = 0; |
bc0c38d1 | 3977 | |
1027fcb2 SR |
3978 | mutex_lock(&trace_types_lock); |
3979 | ||
73c5162a | 3980 | if (!ring_buffer_expanded) { |
2b6080f2 | 3981 | ret = __tracing_resize_ring_buffer(tr, trace_buf_size, |
438ced17 | 3982 | RING_BUFFER_ALL_CPUS); |
73c5162a | 3983 | if (ret < 0) |
59f586db | 3984 | goto out; |
73c5162a SR |
3985 | ret = 0; |
3986 | } | |
3987 | ||
bc0c38d1 SR |
3988 | for (t = trace_types; t; t = t->next) { |
3989 | if (strcmp(t->name, buf) == 0) | |
3990 | break; | |
3991 | } | |
c2931e05 FW |
3992 | if (!t) { |
3993 | ret = -EINVAL; | |
3994 | goto out; | |
3995 | } | |
2b6080f2 | 3996 | if (t == tr->current_trace) |
bc0c38d1 SR |
3997 | goto out; |
3998 | ||
607e2ea1 SRRH |
3999 | /* Some tracers are only allowed for the top level buffer */ |
4000 | if (!trace_ok_for_array(t, tr)) { | |
4001 | ret = -EINVAL; | |
4002 | goto out; | |
4003 | } | |
4004 | ||
9f029e83 | 4005 | trace_branch_disable(); |
613f04a0 | 4006 | |
50512ab5 | 4007 | tr->current_trace->enabled--; |
613f04a0 | 4008 | |
2b6080f2 SR |
4009 | if (tr->current_trace->reset) |
4010 | tr->current_trace->reset(tr); | |
34600f0e | 4011 | |
12883efb | 4012 | /* Current trace needs to be nop_trace before synchronize_sched */ |
2b6080f2 | 4013 | tr->current_trace = &nop_trace; |
34600f0e | 4014 | |
45ad21ca SRRH |
4015 | #ifdef CONFIG_TRACER_MAX_TRACE |
4016 | had_max_tr = tr->allocated_snapshot; | |
34600f0e SR |
4017 | |
4018 | if (had_max_tr && !t->use_max_tr) { | |
4019 | /* | |
4020 | * We need to make sure that the update_max_tr sees that | |
4021 | * current_trace changed to nop_trace to keep it from | |
4022 | * swapping the buffers after we resize it. | |
4023 | * The update_max_tr is called from interrupts disabled | |
4024 | * so a synchronized_sched() is sufficient. | |
4025 | */ | |
4026 | synchronize_sched(); | |
3209cff4 | 4027 | free_snapshot(tr); |
ef710e10 | 4028 | } |
12883efb | 4029 | #endif |
f1b21c9a SRRH |
4030 | /* Currently, only the top instance has options */ |
4031 | if (tr->flags & TRACE_ARRAY_FL_GLOBAL) { | |
4032 | destroy_trace_option_files(topts); | |
4033 | topts = create_trace_option_files(tr, t); | |
4034 | } | |
12883efb SRRH |
4035 | |
4036 | #ifdef CONFIG_TRACER_MAX_TRACE | |
34600f0e | 4037 | if (t->use_max_tr && !had_max_tr) { |
3209cff4 | 4038 | ret = alloc_snapshot(tr); |
d60da506 HT |
4039 | if (ret < 0) |
4040 | goto out; | |
ef710e10 | 4041 | } |
12883efb | 4042 | #endif |
577b785f | 4043 | |
1c80025a | 4044 | if (t->init) { |
b6f11df2 | 4045 | ret = tracer_init(t, tr); |
1c80025a FW |
4046 | if (ret) |
4047 | goto out; | |
4048 | } | |
bc0c38d1 | 4049 | |
2b6080f2 | 4050 | tr->current_trace = t; |
50512ab5 | 4051 | tr->current_trace->enabled++; |
9f029e83 | 4052 | trace_branch_enable(tr); |
bc0c38d1 SR |
4053 | out: |
4054 | mutex_unlock(&trace_types_lock); | |
4055 | ||
d9e54076 PZ |
4056 | return ret; |
4057 | } | |
4058 | ||
4059 | static ssize_t | |
4060 | tracing_set_trace_write(struct file *filp, const char __user *ubuf, | |
4061 | size_t cnt, loff_t *ppos) | |
4062 | { | |
607e2ea1 | 4063 | struct trace_array *tr = filp->private_data; |
ee6c2c1b | 4064 | char buf[MAX_TRACER_SIZE+1]; |
d9e54076 PZ |
4065 | int i; |
4066 | size_t ret; | |
e6e7a65a FW |
4067 | int err; |
4068 | ||
4069 | ret = cnt; | |
d9e54076 | 4070 | |
ee6c2c1b LZ |
4071 | if (cnt > MAX_TRACER_SIZE) |
4072 | cnt = MAX_TRACER_SIZE; | |
d9e54076 PZ |
4073 | |
4074 | if (copy_from_user(&buf, ubuf, cnt)) | |
4075 | return -EFAULT; | |
4076 | ||
4077 | buf[cnt] = 0; | |
4078 | ||
4079 | /* strip ending whitespace. */ | |
4080 | for (i = cnt - 1; i > 0 && isspace(buf[i]); i--) | |
4081 | buf[i] = 0; | |
4082 | ||
607e2ea1 | 4083 | err = tracing_set_tracer(tr, buf); |
e6e7a65a FW |
4084 | if (err) |
4085 | return err; | |
d9e54076 | 4086 | |
cf8517cf | 4087 | *ppos += ret; |
bc0c38d1 | 4088 | |
c2931e05 | 4089 | return ret; |
bc0c38d1 SR |
4090 | } |
4091 | ||
4092 | static ssize_t | |
4093 | tracing_max_lat_read(struct file *filp, char __user *ubuf, | |
4094 | size_t cnt, loff_t *ppos) | |
4095 | { | |
4096 | unsigned long *ptr = filp->private_data; | |
4097 | char buf[64]; | |
4098 | int r; | |
4099 | ||
cffae437 | 4100 | r = snprintf(buf, sizeof(buf), "%ld\n", |
bc0c38d1 | 4101 | *ptr == (unsigned long)-1 ? -1 : nsecs_to_usecs(*ptr)); |
cffae437 SR |
4102 | if (r > sizeof(buf)) |
4103 | r = sizeof(buf); | |
4bf39a94 | 4104 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, r); |
bc0c38d1 SR |
4105 | } |
4106 | ||
4107 | static ssize_t | |
4108 | tracing_max_lat_write(struct file *filp, const char __user *ubuf, | |
4109 | size_t cnt, loff_t *ppos) | |
4110 | { | |
5e39841c | 4111 | unsigned long *ptr = filp->private_data; |
5e39841c | 4112 | unsigned long val; |
c6caeeb1 | 4113 | int ret; |
bc0c38d1 | 4114 | |
22fe9b54 PH |
4115 | ret = kstrtoul_from_user(ubuf, cnt, 10, &val); |
4116 | if (ret) | |
c6caeeb1 | 4117 | return ret; |
bc0c38d1 SR |
4118 | |
4119 | *ptr = val * 1000; | |
4120 | ||
4121 | return cnt; | |
4122 | } | |
4123 | ||
b3806b43 SR |
4124 | static int tracing_open_pipe(struct inode *inode, struct file *filp) |
4125 | { | |
15544209 | 4126 | struct trace_array *tr = inode->i_private; |
b3806b43 | 4127 | struct trace_iterator *iter; |
b04cc6b1 | 4128 | int ret = 0; |
b3806b43 SR |
4129 | |
4130 | if (tracing_disabled) | |
4131 | return -ENODEV; | |
4132 | ||
7b85af63 SRRH |
4133 | if (trace_array_get(tr) < 0) |
4134 | return -ENODEV; | |
4135 | ||
b04cc6b1 FW |
4136 | mutex_lock(&trace_types_lock); |
4137 | ||
b3806b43 SR |
4138 | /* create a buffer to store the information to pass to userspace */ |
4139 | iter = kzalloc(sizeof(*iter), GFP_KERNEL); | |
b04cc6b1 FW |
4140 | if (!iter) { |
4141 | ret = -ENOMEM; | |
f77d09a3 | 4142 | __trace_array_put(tr); |
b04cc6b1 FW |
4143 | goto out; |
4144 | } | |
b3806b43 | 4145 | |
d7350c3f FW |
4146 | /* |
4147 | * We make a copy of the current tracer to avoid concurrent | |
4148 | * changes on it while we are reading. | |
4149 | */ | |
4150 | iter->trace = kmalloc(sizeof(*iter->trace), GFP_KERNEL); | |
4151 | if (!iter->trace) { | |
4152 | ret = -ENOMEM; | |
4153 | goto fail; | |
4154 | } | |
2b6080f2 | 4155 | *iter->trace = *tr->current_trace; |
d7350c3f | 4156 | |
4462344e | 4157 | if (!alloc_cpumask_var(&iter->started, GFP_KERNEL)) { |
b04cc6b1 | 4158 | ret = -ENOMEM; |
d7350c3f | 4159 | goto fail; |
4462344e RR |
4160 | } |
4161 | ||
a309720c | 4162 | /* trace pipe does not show start of buffer */ |
4462344e | 4163 | cpumask_setall(iter->started); |
a309720c | 4164 | |
112f38a7 SR |
4165 | if (trace_flags & TRACE_ITER_LATENCY_FMT) |
4166 | iter->iter_flags |= TRACE_FILE_LAT_FMT; | |
4167 | ||
8be0709f | 4168 | /* Output in nanoseconds only if we are using a clock in nanoseconds. */ |
58e8eedf | 4169 | if (trace_clocks[tr->clock_id].in_ns) |
8be0709f DS |
4170 | iter->iter_flags |= TRACE_FILE_TIME_IN_NS; |
4171 | ||
15544209 ON |
4172 | iter->tr = tr; |
4173 | iter->trace_buffer = &tr->trace_buffer; | |
4174 | iter->cpu_file = tracing_get_cpu(inode); | |
d7350c3f | 4175 | mutex_init(&iter->mutex); |
b3806b43 SR |
4176 | filp->private_data = iter; |
4177 | ||
107bad8b SR |
4178 | if (iter->trace->pipe_open) |
4179 | iter->trace->pipe_open(iter); | |
107bad8b | 4180 | |
b444786f | 4181 | nonseekable_open(inode, filp); |
b04cc6b1 FW |
4182 | out: |
4183 | mutex_unlock(&trace_types_lock); | |
4184 | return ret; | |
d7350c3f FW |
4185 | |
4186 | fail: | |
4187 | kfree(iter->trace); | |
4188 | kfree(iter); | |
7b85af63 | 4189 | __trace_array_put(tr); |
d7350c3f FW |
4190 | mutex_unlock(&trace_types_lock); |
4191 | return ret; | |
b3806b43 SR |
4192 | } |
4193 | ||
4194 | static int tracing_release_pipe(struct inode *inode, struct file *file) | |
4195 | { | |
4196 | struct trace_iterator *iter = file->private_data; | |
15544209 | 4197 | struct trace_array *tr = inode->i_private; |
b3806b43 | 4198 | |
b04cc6b1 FW |
4199 | mutex_lock(&trace_types_lock); |
4200 | ||
29bf4a5e | 4201 | if (iter->trace->pipe_close) |
c521efd1 SR |
4202 | iter->trace->pipe_close(iter); |
4203 | ||
b04cc6b1 FW |
4204 | mutex_unlock(&trace_types_lock); |
4205 | ||
4462344e | 4206 | free_cpumask_var(iter->started); |
d7350c3f FW |
4207 | mutex_destroy(&iter->mutex); |
4208 | kfree(iter->trace); | |
b3806b43 | 4209 | kfree(iter); |
b3806b43 | 4210 | |
7b85af63 SRRH |
4211 | trace_array_put(tr); |
4212 | ||
b3806b43 SR |
4213 | return 0; |
4214 | } | |
4215 | ||
2a2cc8f7 | 4216 | static unsigned int |
cc60cdc9 | 4217 | trace_poll(struct trace_iterator *iter, struct file *filp, poll_table *poll_table) |
2a2cc8f7 | 4218 | { |
15693458 SRRH |
4219 | /* Iterators are static, they should be filled or empty */ |
4220 | if (trace_buffer_iter(iter, iter->cpu_file)) | |
4221 | return POLLIN | POLLRDNORM; | |
2a2cc8f7 | 4222 | |
15693458 | 4223 | if (trace_flags & TRACE_ITER_BLOCK) |
2a2cc8f7 SSP |
4224 | /* |
4225 | * Always select as readable when in blocking mode | |
4226 | */ | |
4227 | return POLLIN | POLLRDNORM; | |
15693458 | 4228 | else |
12883efb | 4229 | return ring_buffer_poll_wait(iter->trace_buffer->buffer, iter->cpu_file, |
15693458 | 4230 | filp, poll_table); |
2a2cc8f7 | 4231 | } |
2a2cc8f7 | 4232 | |
cc60cdc9 SR |
4233 | static unsigned int |
4234 | tracing_poll_pipe(struct file *filp, poll_table *poll_table) | |
4235 | { | |
4236 | struct trace_iterator *iter = filp->private_data; | |
4237 | ||
4238 | return trace_poll(iter, filp, poll_table); | |
2a2cc8f7 SSP |
4239 | } |
4240 | ||
ff98781b EGM |
4241 | /* Must be called with trace_types_lock mutex held. */ |
4242 | static int tracing_wait_pipe(struct file *filp) | |
b3806b43 SR |
4243 | { |
4244 | struct trace_iterator *iter = filp->private_data; | |
b3806b43 | 4245 | |
b3806b43 | 4246 | while (trace_empty(iter)) { |
2dc8f095 | 4247 | |
107bad8b | 4248 | if ((filp->f_flags & O_NONBLOCK)) { |
ff98781b | 4249 | return -EAGAIN; |
107bad8b | 4250 | } |
2dc8f095 | 4251 | |
b3806b43 | 4252 | /* |
250bfd3d | 4253 | * We block until we read something and tracing is disabled. |
b3806b43 SR |
4254 | * We still block if tracing is disabled, but we have never |
4255 | * read anything. This allows a user to cat this file, and | |
4256 | * then enable tracing. But after we have read something, | |
4257 | * we give an EOF when tracing is again disabled. | |
4258 | * | |
4259 | * iter->pos will be 0 if we haven't read anything. | |
4260 | */ | |
10246fa3 | 4261 | if (!tracing_is_on() && iter->pos) |
b3806b43 | 4262 | break; |
f4874261 SRRH |
4263 | |
4264 | mutex_unlock(&iter->mutex); | |
4265 | ||
b1169cc6 | 4266 | wait_on_pipe(iter); |
f4874261 SRRH |
4267 | |
4268 | mutex_lock(&iter->mutex); | |
4269 | ||
4270 | if (signal_pending(current)) | |
4271 | return -EINTR; | |
b3806b43 SR |
4272 | } |
4273 | ||
ff98781b EGM |
4274 | return 1; |
4275 | } | |
4276 | ||
4277 | /* | |
4278 | * Consumer reader. | |
4279 | */ | |
4280 | static ssize_t | |
4281 | tracing_read_pipe(struct file *filp, char __user *ubuf, | |
4282 | size_t cnt, loff_t *ppos) | |
4283 | { | |
4284 | struct trace_iterator *iter = filp->private_data; | |
2b6080f2 | 4285 | struct trace_array *tr = iter->tr; |
ff98781b EGM |
4286 | ssize_t sret; |
4287 | ||
4288 | /* return any leftover data */ | |
4289 | sret = trace_seq_to_user(&iter->seq, ubuf, cnt); | |
4290 | if (sret != -EBUSY) | |
4291 | return sret; | |
4292 | ||
f9520750 | 4293 | trace_seq_init(&iter->seq); |
ff98781b | 4294 | |
d7350c3f | 4295 | /* copy the tracer to avoid using a global lock all around */ |
ff98781b | 4296 | mutex_lock(&trace_types_lock); |
2b6080f2 SR |
4297 | if (unlikely(iter->trace->name != tr->current_trace->name)) |
4298 | *iter->trace = *tr->current_trace; | |
d7350c3f FW |
4299 | mutex_unlock(&trace_types_lock); |
4300 | ||
4301 | /* | |
4302 | * Avoid more than one consumer on a single file descriptor | |
4303 | * This is just a matter of traces coherency, the ring buffer itself | |
4304 | * is protected. | |
4305 | */ | |
4306 | mutex_lock(&iter->mutex); | |
ff98781b EGM |
4307 | if (iter->trace->read) { |
4308 | sret = iter->trace->read(iter, filp, ubuf, cnt, ppos); | |
4309 | if (sret) | |
4310 | goto out; | |
4311 | } | |
4312 | ||
4313 | waitagain: | |
4314 | sret = tracing_wait_pipe(filp); | |
4315 | if (sret <= 0) | |
4316 | goto out; | |
4317 | ||
b3806b43 | 4318 | /* stop when tracing is finished */ |
ff98781b EGM |
4319 | if (trace_empty(iter)) { |
4320 | sret = 0; | |
107bad8b | 4321 | goto out; |
ff98781b | 4322 | } |
b3806b43 SR |
4323 | |
4324 | if (cnt >= PAGE_SIZE) | |
4325 | cnt = PAGE_SIZE - 1; | |
4326 | ||
53d0aa77 | 4327 | /* reset all but tr, trace, and overruns */ |
53d0aa77 SR |
4328 | memset(&iter->seq, 0, |
4329 | sizeof(struct trace_iterator) - | |
4330 | offsetof(struct trace_iterator, seq)); | |
ed5467da | 4331 | cpumask_clear(iter->started); |
4823ed7e | 4332 | iter->pos = -1; |
b3806b43 | 4333 | |
4f535968 | 4334 | trace_event_read_lock(); |
7e53bd42 | 4335 | trace_access_lock(iter->cpu_file); |
955b61e5 | 4336 | while (trace_find_next_entry_inc(iter) != NULL) { |
2c4f035f | 4337 | enum print_line_t ret; |
088b1e42 SR |
4338 | int len = iter->seq.len; |
4339 | ||
f9896bf3 | 4340 | ret = print_trace_line(iter); |
2c4f035f | 4341 | if (ret == TRACE_TYPE_PARTIAL_LINE) { |
088b1e42 SR |
4342 | /* don't print partial lines */ |
4343 | iter->seq.len = len; | |
b3806b43 | 4344 | break; |
088b1e42 | 4345 | } |
b91facc3 FW |
4346 | if (ret != TRACE_TYPE_NO_CONSUME) |
4347 | trace_consume(iter); | |
b3806b43 SR |
4348 | |
4349 | if (iter->seq.len >= cnt) | |
4350 | break; | |
ee5e51f5 JO |
4351 | |
4352 | /* | |
4353 | * Setting the full flag means we reached the trace_seq buffer | |
4354 | * size and we should leave by partial output condition above. | |
4355 | * One of the trace_seq_* functions is not used properly. | |
4356 | */ | |
4357 | WARN_ONCE(iter->seq.full, "full flag set for trace type %d", | |
4358 | iter->ent->type); | |
b3806b43 | 4359 | } |
7e53bd42 | 4360 | trace_access_unlock(iter->cpu_file); |
4f535968 | 4361 | trace_event_read_unlock(); |
b3806b43 | 4362 | |
b3806b43 | 4363 | /* Now copy what we have to the user */ |
6c6c2796 PP |
4364 | sret = trace_seq_to_user(&iter->seq, ubuf, cnt); |
4365 | if (iter->seq.readpos >= iter->seq.len) | |
f9520750 | 4366 | trace_seq_init(&iter->seq); |
9ff4b974 PP |
4367 | |
4368 | /* | |
25985edc | 4369 | * If there was nothing to send to user, in spite of consuming trace |
9ff4b974 PP |
4370 | * entries, go back to wait for more entries. |
4371 | */ | |
6c6c2796 | 4372 | if (sret == -EBUSY) |
9ff4b974 | 4373 | goto waitagain; |
b3806b43 | 4374 | |
107bad8b | 4375 | out: |
d7350c3f | 4376 | mutex_unlock(&iter->mutex); |
107bad8b | 4377 | |
6c6c2796 | 4378 | return sret; |
b3806b43 SR |
4379 | } |
4380 | ||
3c56819b EGM |
4381 | static void tracing_spd_release_pipe(struct splice_pipe_desc *spd, |
4382 | unsigned int idx) | |
4383 | { | |
4384 | __free_page(spd->pages[idx]); | |
4385 | } | |
4386 | ||
28dfef8f | 4387 | static const struct pipe_buf_operations tracing_pipe_buf_ops = { |
34cd4998 | 4388 | .can_merge = 0, |
34cd4998 | 4389 | .confirm = generic_pipe_buf_confirm, |
92fdd98c | 4390 | .release = generic_pipe_buf_release, |
34cd4998 SR |
4391 | .steal = generic_pipe_buf_steal, |
4392 | .get = generic_pipe_buf_get, | |
3c56819b EGM |
4393 | }; |
4394 | ||
34cd4998 | 4395 | static size_t |
fa7c7f6e | 4396 | tracing_fill_pipe_page(size_t rem, struct trace_iterator *iter) |
34cd4998 SR |
4397 | { |
4398 | size_t count; | |
4399 | int ret; | |
4400 | ||
4401 | /* Seq buffer is page-sized, exactly what we need. */ | |
4402 | for (;;) { | |
4403 | count = iter->seq.len; | |
4404 | ret = print_trace_line(iter); | |
4405 | count = iter->seq.len - count; | |
4406 | if (rem < count) { | |
4407 | rem = 0; | |
4408 | iter->seq.len -= count; | |
4409 | break; | |
4410 | } | |
4411 | if (ret == TRACE_TYPE_PARTIAL_LINE) { | |
4412 | iter->seq.len -= count; | |
4413 | break; | |
4414 | } | |
4415 | ||
74e7ff8c LJ |
4416 | if (ret != TRACE_TYPE_NO_CONSUME) |
4417 | trace_consume(iter); | |
34cd4998 | 4418 | rem -= count; |
955b61e5 | 4419 | if (!trace_find_next_entry_inc(iter)) { |
34cd4998 SR |
4420 | rem = 0; |
4421 | iter->ent = NULL; | |
4422 | break; | |
4423 | } | |
4424 | } | |
4425 | ||
4426 | return rem; | |
4427 | } | |
4428 | ||
3c56819b EGM |
4429 | static ssize_t tracing_splice_read_pipe(struct file *filp, |
4430 | loff_t *ppos, | |
4431 | struct pipe_inode_info *pipe, | |
4432 | size_t len, | |
4433 | unsigned int flags) | |
4434 | { | |
35f3d14d JA |
4435 | struct page *pages_def[PIPE_DEF_BUFFERS]; |
4436 | struct partial_page partial_def[PIPE_DEF_BUFFERS]; | |
3c56819b EGM |
4437 | struct trace_iterator *iter = filp->private_data; |
4438 | struct splice_pipe_desc spd = { | |
35f3d14d JA |
4439 | .pages = pages_def, |
4440 | .partial = partial_def, | |
34cd4998 | 4441 | .nr_pages = 0, /* This gets updated below. */ |
047fe360 | 4442 | .nr_pages_max = PIPE_DEF_BUFFERS, |
34cd4998 SR |
4443 | .flags = flags, |
4444 | .ops = &tracing_pipe_buf_ops, | |
4445 | .spd_release = tracing_spd_release_pipe, | |
3c56819b | 4446 | }; |
2b6080f2 | 4447 | struct trace_array *tr = iter->tr; |
3c56819b | 4448 | ssize_t ret; |
34cd4998 | 4449 | size_t rem; |
3c56819b EGM |
4450 | unsigned int i; |
4451 | ||
35f3d14d JA |
4452 | if (splice_grow_spd(pipe, &spd)) |
4453 | return -ENOMEM; | |
4454 | ||
d7350c3f | 4455 | /* copy the tracer to avoid using a global lock all around */ |
3c56819b | 4456 | mutex_lock(&trace_types_lock); |
2b6080f2 SR |
4457 | if (unlikely(iter->trace->name != tr->current_trace->name)) |
4458 | *iter->trace = *tr->current_trace; | |
d7350c3f FW |
4459 | mutex_unlock(&trace_types_lock); |
4460 | ||
4461 | mutex_lock(&iter->mutex); | |
3c56819b EGM |
4462 | |
4463 | if (iter->trace->splice_read) { | |
4464 | ret = iter->trace->splice_read(iter, filp, | |
4465 | ppos, pipe, len, flags); | |
4466 | if (ret) | |
34cd4998 | 4467 | goto out_err; |
3c56819b EGM |
4468 | } |
4469 | ||
4470 | ret = tracing_wait_pipe(filp); | |
4471 | if (ret <= 0) | |
34cd4998 | 4472 | goto out_err; |
3c56819b | 4473 | |
955b61e5 | 4474 | if (!iter->ent && !trace_find_next_entry_inc(iter)) { |
3c56819b | 4475 | ret = -EFAULT; |
34cd4998 | 4476 | goto out_err; |
3c56819b EGM |
4477 | } |
4478 | ||
4f535968 | 4479 | trace_event_read_lock(); |
7e53bd42 | 4480 | trace_access_lock(iter->cpu_file); |
4f535968 | 4481 | |
3c56819b | 4482 | /* Fill as many pages as possible. */ |
a786c06d | 4483 | for (i = 0, rem = len; i < spd.nr_pages_max && rem; i++) { |
35f3d14d JA |
4484 | spd.pages[i] = alloc_page(GFP_KERNEL); |
4485 | if (!spd.pages[i]) | |
34cd4998 | 4486 | break; |
3c56819b | 4487 | |
fa7c7f6e | 4488 | rem = tracing_fill_pipe_page(rem, iter); |
3c56819b EGM |
4489 | |
4490 | /* Copy the data into the page, so we can start over. */ | |
4491 | ret = trace_seq_to_buffer(&iter->seq, | |
35f3d14d | 4492 | page_address(spd.pages[i]), |
3c56819b EGM |
4493 | iter->seq.len); |
4494 | if (ret < 0) { | |
35f3d14d | 4495 | __free_page(spd.pages[i]); |
3c56819b EGM |
4496 | break; |
4497 | } | |
35f3d14d JA |
4498 | spd.partial[i].offset = 0; |
4499 | spd.partial[i].len = iter->seq.len; | |
3c56819b | 4500 | |
f9520750 | 4501 | trace_seq_init(&iter->seq); |
3c56819b EGM |
4502 | } |
4503 | ||
7e53bd42 | 4504 | trace_access_unlock(iter->cpu_file); |
4f535968 | 4505 | trace_event_read_unlock(); |
d7350c3f | 4506 | mutex_unlock(&iter->mutex); |
3c56819b EGM |
4507 | |
4508 | spd.nr_pages = i; | |
4509 | ||
35f3d14d JA |
4510 | ret = splice_to_pipe(pipe, &spd); |
4511 | out: | |
047fe360 | 4512 | splice_shrink_spd(&spd); |
35f3d14d | 4513 | return ret; |
3c56819b | 4514 | |
34cd4998 | 4515 | out_err: |
d7350c3f | 4516 | mutex_unlock(&iter->mutex); |
35f3d14d | 4517 | goto out; |
3c56819b EGM |
4518 | } |
4519 | ||
a98a3c3f SR |
4520 | static ssize_t |
4521 | tracing_entries_read(struct file *filp, char __user *ubuf, | |
4522 | size_t cnt, loff_t *ppos) | |
4523 | { | |
0bc392ee ON |
4524 | struct inode *inode = file_inode(filp); |
4525 | struct trace_array *tr = inode->i_private; | |
4526 | int cpu = tracing_get_cpu(inode); | |
438ced17 VN |
4527 | char buf[64]; |
4528 | int r = 0; | |
4529 | ssize_t ret; | |
a98a3c3f | 4530 | |
db526ca3 | 4531 | mutex_lock(&trace_types_lock); |
438ced17 | 4532 | |
0bc392ee | 4533 | if (cpu == RING_BUFFER_ALL_CPUS) { |
438ced17 VN |
4534 | int cpu, buf_size_same; |
4535 | unsigned long size; | |
4536 | ||
4537 | size = 0; | |
4538 | buf_size_same = 1; | |
4539 | /* check if all cpu sizes are same */ | |
4540 | for_each_tracing_cpu(cpu) { | |
4541 | /* fill in the size from first enabled cpu */ | |
4542 | if (size == 0) | |
12883efb SRRH |
4543 | size = per_cpu_ptr(tr->trace_buffer.data, cpu)->entries; |
4544 | if (size != per_cpu_ptr(tr->trace_buffer.data, cpu)->entries) { | |
438ced17 VN |
4545 | buf_size_same = 0; |
4546 | break; | |
4547 | } | |
4548 | } | |
4549 | ||
4550 | if (buf_size_same) { | |
4551 | if (!ring_buffer_expanded) | |
4552 | r = sprintf(buf, "%lu (expanded: %lu)\n", | |
4553 | size >> 10, | |
4554 | trace_buf_size >> 10); | |
4555 | else | |
4556 | r = sprintf(buf, "%lu\n", size >> 10); | |
4557 | } else | |
4558 | r = sprintf(buf, "X\n"); | |
4559 | } else | |
0bc392ee | 4560 | r = sprintf(buf, "%lu\n", per_cpu_ptr(tr->trace_buffer.data, cpu)->entries >> 10); |
438ced17 | 4561 | |
db526ca3 SR |
4562 | mutex_unlock(&trace_types_lock); |
4563 | ||
438ced17 VN |
4564 | ret = simple_read_from_buffer(ubuf, cnt, ppos, buf, r); |
4565 | return ret; | |
a98a3c3f SR |
4566 | } |
4567 | ||
4568 | static ssize_t | |
4569 | tracing_entries_write(struct file *filp, const char __user *ubuf, | |
4570 | size_t cnt, loff_t *ppos) | |
4571 | { | |
0bc392ee ON |
4572 | struct inode *inode = file_inode(filp); |
4573 | struct trace_array *tr = inode->i_private; | |
a98a3c3f | 4574 | unsigned long val; |
4f271a2a | 4575 | int ret; |
a98a3c3f | 4576 | |
22fe9b54 PH |
4577 | ret = kstrtoul_from_user(ubuf, cnt, 10, &val); |
4578 | if (ret) | |
c6caeeb1 | 4579 | return ret; |
a98a3c3f SR |
4580 | |
4581 | /* must have at least 1 entry */ | |
4582 | if (!val) | |
4583 | return -EINVAL; | |
4584 | ||
1696b2b0 SR |
4585 | /* value is in KB */ |
4586 | val <<= 10; | |
0bc392ee | 4587 | ret = tracing_resize_ring_buffer(tr, val, tracing_get_cpu(inode)); |
4f271a2a VN |
4588 | if (ret < 0) |
4589 | return ret; | |
a98a3c3f | 4590 | |
cf8517cf | 4591 | *ppos += cnt; |
a98a3c3f | 4592 | |
4f271a2a VN |
4593 | return cnt; |
4594 | } | |
bf5e6519 | 4595 | |
f81ab074 VN |
4596 | static ssize_t |
4597 | tracing_total_entries_read(struct file *filp, char __user *ubuf, | |
4598 | size_t cnt, loff_t *ppos) | |
4599 | { | |
4600 | struct trace_array *tr = filp->private_data; | |
4601 | char buf[64]; | |
4602 | int r, cpu; | |
4603 | unsigned long size = 0, expanded_size = 0; | |
4604 | ||
4605 | mutex_lock(&trace_types_lock); | |
4606 | for_each_tracing_cpu(cpu) { | |
12883efb | 4607 | size += per_cpu_ptr(tr->trace_buffer.data, cpu)->entries >> 10; |
f81ab074 VN |
4608 | if (!ring_buffer_expanded) |
4609 | expanded_size += trace_buf_size >> 10; | |
4610 | } | |
4611 | if (ring_buffer_expanded) | |
4612 | r = sprintf(buf, "%lu\n", size); | |
4613 | else | |
4614 | r = sprintf(buf, "%lu (expanded: %lu)\n", size, expanded_size); | |
4615 | mutex_unlock(&trace_types_lock); | |
4616 | ||
4617 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, r); | |
4618 | } | |
4619 | ||
4f271a2a VN |
4620 | static ssize_t |
4621 | tracing_free_buffer_write(struct file *filp, const char __user *ubuf, | |
4622 | size_t cnt, loff_t *ppos) | |
4623 | { | |
4624 | /* | |
4625 | * There is no need to read what the user has written, this function | |
4626 | * is just to make sure that there is no error when "echo" is used | |
4627 | */ | |
4628 | ||
4629 | *ppos += cnt; | |
a98a3c3f SR |
4630 | |
4631 | return cnt; | |
4632 | } | |
4633 | ||
4f271a2a VN |
4634 | static int |
4635 | tracing_free_buffer_release(struct inode *inode, struct file *filp) | |
4636 | { | |
2b6080f2 SR |
4637 | struct trace_array *tr = inode->i_private; |
4638 | ||
cf30cf67 SR |
4639 | /* disable tracing ? */ |
4640 | if (trace_flags & TRACE_ITER_STOP_ON_FREE) | |
711e1243 | 4641 | tracer_tracing_off(tr); |
4f271a2a | 4642 | /* resize the ring buffer to 0 */ |
2b6080f2 | 4643 | tracing_resize_ring_buffer(tr, 0, RING_BUFFER_ALL_CPUS); |
4f271a2a | 4644 | |
7b85af63 SRRH |
4645 | trace_array_put(tr); |
4646 | ||
4f271a2a VN |
4647 | return 0; |
4648 | } | |
4649 | ||
5bf9a1ee PP |
4650 | static ssize_t |
4651 | tracing_mark_write(struct file *filp, const char __user *ubuf, | |
4652 | size_t cnt, loff_t *fpos) | |
4653 | { | |
d696b58c | 4654 | unsigned long addr = (unsigned long)ubuf; |
2d71619c | 4655 | struct trace_array *tr = filp->private_data; |
d696b58c SR |
4656 | struct ring_buffer_event *event; |
4657 | struct ring_buffer *buffer; | |
4658 | struct print_entry *entry; | |
4659 | unsigned long irq_flags; | |
4660 | struct page *pages[2]; | |
6edb2a8a | 4661 | void *map_page[2]; |
d696b58c SR |
4662 | int nr_pages = 1; |
4663 | ssize_t written; | |
d696b58c SR |
4664 | int offset; |
4665 | int size; | |
4666 | int len; | |
4667 | int ret; | |
6edb2a8a | 4668 | int i; |
5bf9a1ee | 4669 | |
c76f0694 | 4670 | if (tracing_disabled) |
5bf9a1ee PP |
4671 | return -EINVAL; |
4672 | ||
5224c3a3 MSB |
4673 | if (!(trace_flags & TRACE_ITER_MARKERS)) |
4674 | return -EINVAL; | |
4675 | ||
5bf9a1ee PP |
4676 | if (cnt > TRACE_BUF_SIZE) |
4677 | cnt = TRACE_BUF_SIZE; | |
4678 | ||
d696b58c SR |
4679 | /* |
4680 | * Userspace is injecting traces into the kernel trace buffer. | |
4681 | * We want to be as non intrusive as possible. | |
4682 | * To do so, we do not want to allocate any special buffers | |
4683 | * or take any locks, but instead write the userspace data | |
4684 | * straight into the ring buffer. | |
4685 | * | |
4686 | * First we need to pin the userspace buffer into memory, | |
4687 | * which, most likely it is, because it just referenced it. | |
4688 | * But there's no guarantee that it is. By using get_user_pages_fast() | |
4689 | * and kmap_atomic/kunmap_atomic() we can get access to the | |
4690 | * pages directly. We then write the data directly into the | |
4691 | * ring buffer. | |
4692 | */ | |
4693 | BUILD_BUG_ON(TRACE_BUF_SIZE >= PAGE_SIZE); | |
5bf9a1ee | 4694 | |
d696b58c SR |
4695 | /* check if we cross pages */ |
4696 | if ((addr & PAGE_MASK) != ((addr + cnt) & PAGE_MASK)) | |
4697 | nr_pages = 2; | |
4698 | ||
4699 | offset = addr & (PAGE_SIZE - 1); | |
4700 | addr &= PAGE_MASK; | |
4701 | ||
4702 | ret = get_user_pages_fast(addr, nr_pages, 0, pages); | |
4703 | if (ret < nr_pages) { | |
4704 | while (--ret >= 0) | |
4705 | put_page(pages[ret]); | |
4706 | written = -EFAULT; | |
4707 | goto out; | |
5bf9a1ee | 4708 | } |
d696b58c | 4709 | |
6edb2a8a SR |
4710 | for (i = 0; i < nr_pages; i++) |
4711 | map_page[i] = kmap_atomic(pages[i]); | |
d696b58c SR |
4712 | |
4713 | local_save_flags(irq_flags); | |
4714 | size = sizeof(*entry) + cnt + 2; /* possible \n added */ | |
2d71619c | 4715 | buffer = tr->trace_buffer.buffer; |
d696b58c SR |
4716 | event = trace_buffer_lock_reserve(buffer, TRACE_PRINT, size, |
4717 | irq_flags, preempt_count()); | |
4718 | if (!event) { | |
4719 | /* Ring buffer disabled, return as if not open for write */ | |
4720 | written = -EBADF; | |
4721 | goto out_unlock; | |
5bf9a1ee | 4722 | } |
d696b58c SR |
4723 | |
4724 | entry = ring_buffer_event_data(event); | |
4725 | entry->ip = _THIS_IP_; | |
4726 | ||
4727 | if (nr_pages == 2) { | |
4728 | len = PAGE_SIZE - offset; | |
6edb2a8a SR |
4729 | memcpy(&entry->buf, map_page[0] + offset, len); |
4730 | memcpy(&entry->buf[len], map_page[1], cnt - len); | |
c13d2f7c | 4731 | } else |
6edb2a8a | 4732 | memcpy(&entry->buf, map_page[0] + offset, cnt); |
5bf9a1ee | 4733 | |
d696b58c SR |
4734 | if (entry->buf[cnt - 1] != '\n') { |
4735 | entry->buf[cnt] = '\n'; | |
4736 | entry->buf[cnt + 1] = '\0'; | |
4737 | } else | |
4738 | entry->buf[cnt] = '\0'; | |
4739 | ||
7ffbd48d | 4740 | __buffer_unlock_commit(buffer, event); |
5bf9a1ee | 4741 | |
d696b58c | 4742 | written = cnt; |
5bf9a1ee | 4743 | |
d696b58c | 4744 | *fpos += written; |
1aa54bca | 4745 | |
d696b58c | 4746 | out_unlock: |
6edb2a8a SR |
4747 | for (i = 0; i < nr_pages; i++){ |
4748 | kunmap_atomic(map_page[i]); | |
4749 | put_page(pages[i]); | |
4750 | } | |
d696b58c | 4751 | out: |
1aa54bca | 4752 | return written; |
5bf9a1ee PP |
4753 | } |
4754 | ||
13f16d20 | 4755 | static int tracing_clock_show(struct seq_file *m, void *v) |
5079f326 | 4756 | { |
2b6080f2 | 4757 | struct trace_array *tr = m->private; |
5079f326 Z |
4758 | int i; |
4759 | ||
4760 | for (i = 0; i < ARRAY_SIZE(trace_clocks); i++) | |
13f16d20 | 4761 | seq_printf(m, |
5079f326 | 4762 | "%s%s%s%s", i ? " " : "", |
2b6080f2 SR |
4763 | i == tr->clock_id ? "[" : "", trace_clocks[i].name, |
4764 | i == tr->clock_id ? "]" : ""); | |
13f16d20 | 4765 | seq_putc(m, '\n'); |
5079f326 | 4766 | |
13f16d20 | 4767 | return 0; |
5079f326 Z |
4768 | } |
4769 | ||
e1e232ca | 4770 | static int tracing_set_clock(struct trace_array *tr, const char *clockstr) |
5079f326 | 4771 | { |
5079f326 Z |
4772 | int i; |
4773 | ||
5079f326 Z |
4774 | for (i = 0; i < ARRAY_SIZE(trace_clocks); i++) { |
4775 | if (strcmp(trace_clocks[i].name, clockstr) == 0) | |
4776 | break; | |
4777 | } | |
4778 | if (i == ARRAY_SIZE(trace_clocks)) | |
4779 | return -EINVAL; | |
4780 | ||
5079f326 Z |
4781 | mutex_lock(&trace_types_lock); |
4782 | ||
2b6080f2 SR |
4783 | tr->clock_id = i; |
4784 | ||
12883efb | 4785 | ring_buffer_set_clock(tr->trace_buffer.buffer, trace_clocks[i].func); |
5079f326 | 4786 | |
60303ed3 DS |
4787 | /* |
4788 | * New clock may not be consistent with the previous clock. | |
4789 | * Reset the buffer so that it doesn't have incomparable timestamps. | |
4790 | */ | |
9457158b | 4791 | tracing_reset_online_cpus(&tr->trace_buffer); |
12883efb SRRH |
4792 | |
4793 | #ifdef CONFIG_TRACER_MAX_TRACE | |
4794 | if (tr->flags & TRACE_ARRAY_FL_GLOBAL && tr->max_buffer.buffer) | |
4795 | ring_buffer_set_clock(tr->max_buffer.buffer, trace_clocks[i].func); | |
9457158b | 4796 | tracing_reset_online_cpus(&tr->max_buffer); |
12883efb | 4797 | #endif |
60303ed3 | 4798 | |
5079f326 Z |
4799 | mutex_unlock(&trace_types_lock); |
4800 | ||
e1e232ca SR |
4801 | return 0; |
4802 | } | |
4803 | ||
4804 | static ssize_t tracing_clock_write(struct file *filp, const char __user *ubuf, | |
4805 | size_t cnt, loff_t *fpos) | |
4806 | { | |
4807 | struct seq_file *m = filp->private_data; | |
4808 | struct trace_array *tr = m->private; | |
4809 | char buf[64]; | |
4810 | const char *clockstr; | |
4811 | int ret; | |
4812 | ||
4813 | if (cnt >= sizeof(buf)) | |
4814 | return -EINVAL; | |
4815 | ||
4816 | if (copy_from_user(&buf, ubuf, cnt)) | |
4817 | return -EFAULT; | |
4818 | ||
4819 | buf[cnt] = 0; | |
4820 | ||
4821 | clockstr = strstrip(buf); | |
4822 | ||
4823 | ret = tracing_set_clock(tr, clockstr); | |
4824 | if (ret) | |
4825 | return ret; | |
4826 | ||
5079f326 Z |
4827 | *fpos += cnt; |
4828 | ||
4829 | return cnt; | |
4830 | } | |
4831 | ||
13f16d20 LZ |
4832 | static int tracing_clock_open(struct inode *inode, struct file *file) |
4833 | { | |
7b85af63 SRRH |
4834 | struct trace_array *tr = inode->i_private; |
4835 | int ret; | |
4836 | ||
13f16d20 LZ |
4837 | if (tracing_disabled) |
4838 | return -ENODEV; | |
2b6080f2 | 4839 | |
7b85af63 SRRH |
4840 | if (trace_array_get(tr)) |
4841 | return -ENODEV; | |
4842 | ||
4843 | ret = single_open(file, tracing_clock_show, inode->i_private); | |
4844 | if (ret < 0) | |
4845 | trace_array_put(tr); | |
4846 | ||
4847 | return ret; | |
13f16d20 LZ |
4848 | } |
4849 | ||
6de58e62 SRRH |
4850 | struct ftrace_buffer_info { |
4851 | struct trace_iterator iter; | |
4852 | void *spare; | |
4853 | unsigned int read; | |
4854 | }; | |
4855 | ||
debdd57f HT |
4856 | #ifdef CONFIG_TRACER_SNAPSHOT |
4857 | static int tracing_snapshot_open(struct inode *inode, struct file *file) | |
4858 | { | |
6484c71c | 4859 | struct trace_array *tr = inode->i_private; |
debdd57f | 4860 | struct trace_iterator *iter; |
2b6080f2 | 4861 | struct seq_file *m; |
debdd57f HT |
4862 | int ret = 0; |
4863 | ||
ff451961 SRRH |
4864 | if (trace_array_get(tr) < 0) |
4865 | return -ENODEV; | |
4866 | ||
debdd57f | 4867 | if (file->f_mode & FMODE_READ) { |
6484c71c | 4868 | iter = __tracing_open(inode, file, true); |
debdd57f HT |
4869 | if (IS_ERR(iter)) |
4870 | ret = PTR_ERR(iter); | |
2b6080f2 SR |
4871 | } else { |
4872 | /* Writes still need the seq_file to hold the private data */ | |
f77d09a3 | 4873 | ret = -ENOMEM; |
2b6080f2 SR |
4874 | m = kzalloc(sizeof(*m), GFP_KERNEL); |
4875 | if (!m) | |
f77d09a3 | 4876 | goto out; |
2b6080f2 SR |
4877 | iter = kzalloc(sizeof(*iter), GFP_KERNEL); |
4878 | if (!iter) { | |
4879 | kfree(m); | |
f77d09a3 | 4880 | goto out; |
2b6080f2 | 4881 | } |
f77d09a3 AL |
4882 | ret = 0; |
4883 | ||
ff451961 | 4884 | iter->tr = tr; |
6484c71c ON |
4885 | iter->trace_buffer = &tr->max_buffer; |
4886 | iter->cpu_file = tracing_get_cpu(inode); | |
2b6080f2 SR |
4887 | m->private = iter; |
4888 | file->private_data = m; | |
debdd57f | 4889 | } |
f77d09a3 | 4890 | out: |
ff451961 SRRH |
4891 | if (ret < 0) |
4892 | trace_array_put(tr); | |
4893 | ||
debdd57f HT |
4894 | return ret; |
4895 | } | |
4896 | ||
4897 | static ssize_t | |
4898 | tracing_snapshot_write(struct file *filp, const char __user *ubuf, size_t cnt, | |
4899 | loff_t *ppos) | |
4900 | { | |
2b6080f2 SR |
4901 | struct seq_file *m = filp->private_data; |
4902 | struct trace_iterator *iter = m->private; | |
4903 | struct trace_array *tr = iter->tr; | |
debdd57f HT |
4904 | unsigned long val; |
4905 | int ret; | |
4906 | ||
4907 | ret = tracing_update_buffers(); | |
4908 | if (ret < 0) | |
4909 | return ret; | |
4910 | ||
4911 | ret = kstrtoul_from_user(ubuf, cnt, 10, &val); | |
4912 | if (ret) | |
4913 | return ret; | |
4914 | ||
4915 | mutex_lock(&trace_types_lock); | |
4916 | ||
2b6080f2 | 4917 | if (tr->current_trace->use_max_tr) { |
debdd57f HT |
4918 | ret = -EBUSY; |
4919 | goto out; | |
4920 | } | |
4921 | ||
4922 | switch (val) { | |
4923 | case 0: | |
f1affcaa SRRH |
4924 | if (iter->cpu_file != RING_BUFFER_ALL_CPUS) { |
4925 | ret = -EINVAL; | |
4926 | break; | |
debdd57f | 4927 | } |
3209cff4 SRRH |
4928 | if (tr->allocated_snapshot) |
4929 | free_snapshot(tr); | |
debdd57f HT |
4930 | break; |
4931 | case 1: | |
f1affcaa SRRH |
4932 | /* Only allow per-cpu swap if the ring buffer supports it */ |
4933 | #ifndef CONFIG_RING_BUFFER_ALLOW_SWAP | |
4934 | if (iter->cpu_file != RING_BUFFER_ALL_CPUS) { | |
4935 | ret = -EINVAL; | |
4936 | break; | |
4937 | } | |
4938 | #endif | |
45ad21ca | 4939 | if (!tr->allocated_snapshot) { |
3209cff4 | 4940 | ret = alloc_snapshot(tr); |
debdd57f HT |
4941 | if (ret < 0) |
4942 | break; | |
debdd57f | 4943 | } |
debdd57f HT |
4944 | local_irq_disable(); |
4945 | /* Now, we're going to swap */ | |
f1affcaa | 4946 | if (iter->cpu_file == RING_BUFFER_ALL_CPUS) |
ce9bae55 | 4947 | update_max_tr(tr, current, smp_processor_id()); |
f1affcaa | 4948 | else |
ce9bae55 | 4949 | update_max_tr_single(tr, current, iter->cpu_file); |
debdd57f HT |
4950 | local_irq_enable(); |
4951 | break; | |
4952 | default: | |
45ad21ca | 4953 | if (tr->allocated_snapshot) { |
f1affcaa SRRH |
4954 | if (iter->cpu_file == RING_BUFFER_ALL_CPUS) |
4955 | tracing_reset_online_cpus(&tr->max_buffer); | |
4956 | else | |
4957 | tracing_reset(&tr->max_buffer, iter->cpu_file); | |
4958 | } | |
debdd57f HT |
4959 | break; |
4960 | } | |
4961 | ||
4962 | if (ret >= 0) { | |
4963 | *ppos += cnt; | |
4964 | ret = cnt; | |
4965 | } | |
4966 | out: | |
4967 | mutex_unlock(&trace_types_lock); | |
4968 | return ret; | |
4969 | } | |
2b6080f2 SR |
4970 | |
4971 | static int tracing_snapshot_release(struct inode *inode, struct file *file) | |
4972 | { | |
4973 | struct seq_file *m = file->private_data; | |
ff451961 SRRH |
4974 | int ret; |
4975 | ||
4976 | ret = tracing_release(inode, file); | |
2b6080f2 SR |
4977 | |
4978 | if (file->f_mode & FMODE_READ) | |
ff451961 | 4979 | return ret; |
2b6080f2 SR |
4980 | |
4981 | /* If write only, the seq_file is just a stub */ | |
4982 | if (m) | |
4983 | kfree(m->private); | |
4984 | kfree(m); | |
4985 | ||
4986 | return 0; | |
4987 | } | |
4988 | ||
6de58e62 SRRH |
4989 | static int tracing_buffers_open(struct inode *inode, struct file *filp); |
4990 | static ssize_t tracing_buffers_read(struct file *filp, char __user *ubuf, | |
4991 | size_t count, loff_t *ppos); | |
4992 | static int tracing_buffers_release(struct inode *inode, struct file *file); | |
4993 | static ssize_t tracing_buffers_splice_read(struct file *file, loff_t *ppos, | |
4994 | struct pipe_inode_info *pipe, size_t len, unsigned int flags); | |
4995 | ||
4996 | static int snapshot_raw_open(struct inode *inode, struct file *filp) | |
4997 | { | |
4998 | struct ftrace_buffer_info *info; | |
4999 | int ret; | |
5000 | ||
5001 | ret = tracing_buffers_open(inode, filp); | |
5002 | if (ret < 0) | |
5003 | return ret; | |
5004 | ||
5005 | info = filp->private_data; | |
5006 | ||
5007 | if (info->iter.trace->use_max_tr) { | |
5008 | tracing_buffers_release(inode, filp); | |
5009 | return -EBUSY; | |
5010 | } | |
5011 | ||
5012 | info->iter.snapshot = true; | |
5013 | info->iter.trace_buffer = &info->iter.tr->max_buffer; | |
5014 | ||
5015 | return ret; | |
5016 | } | |
5017 | ||
debdd57f HT |
5018 | #endif /* CONFIG_TRACER_SNAPSHOT */ |
5019 | ||
5020 | ||
5e2336a0 | 5021 | static const struct file_operations tracing_max_lat_fops = { |
4bf39a94 IM |
5022 | .open = tracing_open_generic, |
5023 | .read = tracing_max_lat_read, | |
5024 | .write = tracing_max_lat_write, | |
b444786f | 5025 | .llseek = generic_file_llseek, |
bc0c38d1 SR |
5026 | }; |
5027 | ||
5e2336a0 | 5028 | static const struct file_operations set_tracer_fops = { |
4bf39a94 IM |
5029 | .open = tracing_open_generic, |
5030 | .read = tracing_set_trace_read, | |
5031 | .write = tracing_set_trace_write, | |
b444786f | 5032 | .llseek = generic_file_llseek, |
bc0c38d1 SR |
5033 | }; |
5034 | ||
5e2336a0 | 5035 | static const struct file_operations tracing_pipe_fops = { |
4bf39a94 | 5036 | .open = tracing_open_pipe, |
2a2cc8f7 | 5037 | .poll = tracing_poll_pipe, |
4bf39a94 | 5038 | .read = tracing_read_pipe, |
3c56819b | 5039 | .splice_read = tracing_splice_read_pipe, |
4bf39a94 | 5040 | .release = tracing_release_pipe, |
b444786f | 5041 | .llseek = no_llseek, |
b3806b43 SR |
5042 | }; |
5043 | ||
5e2336a0 | 5044 | static const struct file_operations tracing_entries_fops = { |
0bc392ee | 5045 | .open = tracing_open_generic_tr, |
a98a3c3f SR |
5046 | .read = tracing_entries_read, |
5047 | .write = tracing_entries_write, | |
b444786f | 5048 | .llseek = generic_file_llseek, |
0bc392ee | 5049 | .release = tracing_release_generic_tr, |
a98a3c3f SR |
5050 | }; |
5051 | ||
f81ab074 | 5052 | static const struct file_operations tracing_total_entries_fops = { |
7b85af63 | 5053 | .open = tracing_open_generic_tr, |
f81ab074 VN |
5054 | .read = tracing_total_entries_read, |
5055 | .llseek = generic_file_llseek, | |
7b85af63 | 5056 | .release = tracing_release_generic_tr, |
f81ab074 VN |
5057 | }; |
5058 | ||
4f271a2a | 5059 | static const struct file_operations tracing_free_buffer_fops = { |
7b85af63 | 5060 | .open = tracing_open_generic_tr, |
4f271a2a VN |
5061 | .write = tracing_free_buffer_write, |
5062 | .release = tracing_free_buffer_release, | |
5063 | }; | |
5064 | ||
5e2336a0 | 5065 | static const struct file_operations tracing_mark_fops = { |
7b85af63 | 5066 | .open = tracing_open_generic_tr, |
5bf9a1ee | 5067 | .write = tracing_mark_write, |
b444786f | 5068 | .llseek = generic_file_llseek, |
7b85af63 | 5069 | .release = tracing_release_generic_tr, |
5bf9a1ee PP |
5070 | }; |
5071 | ||
5079f326 | 5072 | static const struct file_operations trace_clock_fops = { |
13f16d20 LZ |
5073 | .open = tracing_clock_open, |
5074 | .read = seq_read, | |
5075 | .llseek = seq_lseek, | |
7b85af63 | 5076 | .release = tracing_single_release_tr, |
5079f326 Z |
5077 | .write = tracing_clock_write, |
5078 | }; | |
5079 | ||
debdd57f HT |
5080 | #ifdef CONFIG_TRACER_SNAPSHOT |
5081 | static const struct file_operations snapshot_fops = { | |
5082 | .open = tracing_snapshot_open, | |
5083 | .read = seq_read, | |
5084 | .write = tracing_snapshot_write, | |
098c879e | 5085 | .llseek = tracing_lseek, |
2b6080f2 | 5086 | .release = tracing_snapshot_release, |
debdd57f | 5087 | }; |
debdd57f | 5088 | |
6de58e62 SRRH |
5089 | static const struct file_operations snapshot_raw_fops = { |
5090 | .open = snapshot_raw_open, | |
5091 | .read = tracing_buffers_read, | |
5092 | .release = tracing_buffers_release, | |
5093 | .splice_read = tracing_buffers_splice_read, | |
5094 | .llseek = no_llseek, | |
2cadf913 SR |
5095 | }; |
5096 | ||
6de58e62 SRRH |
5097 | #endif /* CONFIG_TRACER_SNAPSHOT */ |
5098 | ||
2cadf913 SR |
5099 | static int tracing_buffers_open(struct inode *inode, struct file *filp) |
5100 | { | |
46ef2be0 | 5101 | struct trace_array *tr = inode->i_private; |
2cadf913 | 5102 | struct ftrace_buffer_info *info; |
7b85af63 | 5103 | int ret; |
2cadf913 SR |
5104 | |
5105 | if (tracing_disabled) | |
5106 | return -ENODEV; | |
5107 | ||
7b85af63 SRRH |
5108 | if (trace_array_get(tr) < 0) |
5109 | return -ENODEV; | |
5110 | ||
2cadf913 | 5111 | info = kzalloc(sizeof(*info), GFP_KERNEL); |
7b85af63 SRRH |
5112 | if (!info) { |
5113 | trace_array_put(tr); | |
2cadf913 | 5114 | return -ENOMEM; |
7b85af63 | 5115 | } |
2cadf913 | 5116 | |
a695cb58 SRRH |
5117 | mutex_lock(&trace_types_lock); |
5118 | ||
cc60cdc9 | 5119 | info->iter.tr = tr; |
46ef2be0 | 5120 | info->iter.cpu_file = tracing_get_cpu(inode); |
b627344f | 5121 | info->iter.trace = tr->current_trace; |
12883efb | 5122 | info->iter.trace_buffer = &tr->trace_buffer; |
cc60cdc9 | 5123 | info->spare = NULL; |
2cadf913 | 5124 | /* Force reading ring buffer for first read */ |
cc60cdc9 | 5125 | info->read = (unsigned int)-1; |
2cadf913 SR |
5126 | |
5127 | filp->private_data = info; | |
5128 | ||
a695cb58 SRRH |
5129 | mutex_unlock(&trace_types_lock); |
5130 | ||
7b85af63 SRRH |
5131 | ret = nonseekable_open(inode, filp); |
5132 | if (ret < 0) | |
5133 | trace_array_put(tr); | |
5134 | ||
5135 | return ret; | |
2cadf913 SR |
5136 | } |
5137 | ||
cc60cdc9 SR |
5138 | static unsigned int |
5139 | tracing_buffers_poll(struct file *filp, poll_table *poll_table) | |
5140 | { | |
5141 | struct ftrace_buffer_info *info = filp->private_data; | |
5142 | struct trace_iterator *iter = &info->iter; | |
5143 | ||
5144 | return trace_poll(iter, filp, poll_table); | |
5145 | } | |
5146 | ||
2cadf913 SR |
5147 | static ssize_t |
5148 | tracing_buffers_read(struct file *filp, char __user *ubuf, | |
5149 | size_t count, loff_t *ppos) | |
5150 | { | |
5151 | struct ftrace_buffer_info *info = filp->private_data; | |
cc60cdc9 | 5152 | struct trace_iterator *iter = &info->iter; |
2cadf913 | 5153 | ssize_t ret; |
6de58e62 | 5154 | ssize_t size; |
2cadf913 | 5155 | |
2dc5d12b SR |
5156 | if (!count) |
5157 | return 0; | |
5158 | ||
6de58e62 SRRH |
5159 | mutex_lock(&trace_types_lock); |
5160 | ||
5161 | #ifdef CONFIG_TRACER_MAX_TRACE | |
5162 | if (iter->snapshot && iter->tr->current_trace->use_max_tr) { | |
5163 | size = -EBUSY; | |
5164 | goto out_unlock; | |
5165 | } | |
5166 | #endif | |
5167 | ||
ddd538f3 | 5168 | if (!info->spare) |
12883efb SRRH |
5169 | info->spare = ring_buffer_alloc_read_page(iter->trace_buffer->buffer, |
5170 | iter->cpu_file); | |
6de58e62 | 5171 | size = -ENOMEM; |
ddd538f3 | 5172 | if (!info->spare) |
6de58e62 | 5173 | goto out_unlock; |
ddd538f3 | 5174 | |
2cadf913 SR |
5175 | /* Do we have previous read data to read? */ |
5176 | if (info->read < PAGE_SIZE) | |
5177 | goto read; | |
5178 | ||
b627344f | 5179 | again: |
cc60cdc9 | 5180 | trace_access_lock(iter->cpu_file); |
12883efb | 5181 | ret = ring_buffer_read_page(iter->trace_buffer->buffer, |
2cadf913 SR |
5182 | &info->spare, |
5183 | count, | |
cc60cdc9 SR |
5184 | iter->cpu_file, 0); |
5185 | trace_access_unlock(iter->cpu_file); | |
2cadf913 | 5186 | |
b627344f SR |
5187 | if (ret < 0) { |
5188 | if (trace_empty(iter)) { | |
6de58e62 SRRH |
5189 | if ((filp->f_flags & O_NONBLOCK)) { |
5190 | size = -EAGAIN; | |
5191 | goto out_unlock; | |
5192 | } | |
5193 | mutex_unlock(&trace_types_lock); | |
b1169cc6 | 5194 | wait_on_pipe(iter); |
6de58e62 SRRH |
5195 | mutex_lock(&trace_types_lock); |
5196 | if (signal_pending(current)) { | |
5197 | size = -EINTR; | |
5198 | goto out_unlock; | |
5199 | } | |
b627344f SR |
5200 | goto again; |
5201 | } | |
6de58e62 SRRH |
5202 | size = 0; |
5203 | goto out_unlock; | |
b627344f | 5204 | } |
436fc280 | 5205 | |
436fc280 | 5206 | info->read = 0; |
b627344f | 5207 | read: |
2cadf913 SR |
5208 | size = PAGE_SIZE - info->read; |
5209 | if (size > count) | |
5210 | size = count; | |
5211 | ||
5212 | ret = copy_to_user(ubuf, info->spare + info->read, size); | |
6de58e62 SRRH |
5213 | if (ret == size) { |
5214 | size = -EFAULT; | |
5215 | goto out_unlock; | |
5216 | } | |
2dc5d12b SR |
5217 | size -= ret; |
5218 | ||
2cadf913 SR |
5219 | *ppos += size; |
5220 | info->read += size; | |
5221 | ||
6de58e62 SRRH |
5222 | out_unlock: |
5223 | mutex_unlock(&trace_types_lock); | |
5224 | ||
2cadf913 SR |
5225 | return size; |
5226 | } | |
5227 | ||
5228 | static int tracing_buffers_release(struct inode *inode, struct file *file) | |
5229 | { | |
5230 | struct ftrace_buffer_info *info = file->private_data; | |
cc60cdc9 | 5231 | struct trace_iterator *iter = &info->iter; |
2cadf913 | 5232 | |
a695cb58 SRRH |
5233 | mutex_lock(&trace_types_lock); |
5234 | ||
ff451961 | 5235 | __trace_array_put(iter->tr); |
2cadf913 | 5236 | |
ddd538f3 | 5237 | if (info->spare) |
12883efb | 5238 | ring_buffer_free_read_page(iter->trace_buffer->buffer, info->spare); |
2cadf913 SR |
5239 | kfree(info); |
5240 | ||
a695cb58 SRRH |
5241 | mutex_unlock(&trace_types_lock); |
5242 | ||
2cadf913 SR |
5243 | return 0; |
5244 | } | |
5245 | ||
5246 | struct buffer_ref { | |
5247 | struct ring_buffer *buffer; | |
5248 | void *page; | |
5249 | int ref; | |
5250 | }; | |
5251 | ||
5252 | static void buffer_pipe_buf_release(struct pipe_inode_info *pipe, | |
5253 | struct pipe_buffer *buf) | |
5254 | { | |
5255 | struct buffer_ref *ref = (struct buffer_ref *)buf->private; | |
5256 | ||
5257 | if (--ref->ref) | |
5258 | return; | |
5259 | ||
5260 | ring_buffer_free_read_page(ref->buffer, ref->page); | |
5261 | kfree(ref); | |
5262 | buf->private = 0; | |
5263 | } | |
5264 | ||
2cadf913 SR |
5265 | static void buffer_pipe_buf_get(struct pipe_inode_info *pipe, |
5266 | struct pipe_buffer *buf) | |
5267 | { | |
5268 | struct buffer_ref *ref = (struct buffer_ref *)buf->private; | |
5269 | ||
5270 | ref->ref++; | |
5271 | } | |
5272 | ||
5273 | /* Pipe buffer operations for a buffer. */ | |
28dfef8f | 5274 | static const struct pipe_buf_operations buffer_pipe_buf_ops = { |
2cadf913 | 5275 | .can_merge = 0, |
2cadf913 SR |
5276 | .confirm = generic_pipe_buf_confirm, |
5277 | .release = buffer_pipe_buf_release, | |
d55cb6cf | 5278 | .steal = generic_pipe_buf_steal, |
2cadf913 SR |
5279 | .get = buffer_pipe_buf_get, |
5280 | }; | |
5281 | ||
5282 | /* | |
5283 | * Callback from splice_to_pipe(), if we need to release some pages | |
5284 | * at the end of the spd in case we error'ed out in filling the pipe. | |
5285 | */ | |
5286 | static void buffer_spd_release(struct splice_pipe_desc *spd, unsigned int i) | |
5287 | { | |
5288 | struct buffer_ref *ref = | |
5289 | (struct buffer_ref *)spd->partial[i].private; | |
5290 | ||
5291 | if (--ref->ref) | |
5292 | return; | |
5293 | ||
5294 | ring_buffer_free_read_page(ref->buffer, ref->page); | |
5295 | kfree(ref); | |
5296 | spd->partial[i].private = 0; | |
5297 | } | |
5298 | ||
5299 | static ssize_t | |
5300 | tracing_buffers_splice_read(struct file *file, loff_t *ppos, | |
5301 | struct pipe_inode_info *pipe, size_t len, | |
5302 | unsigned int flags) | |
5303 | { | |
5304 | struct ftrace_buffer_info *info = file->private_data; | |
cc60cdc9 | 5305 | struct trace_iterator *iter = &info->iter; |
35f3d14d JA |
5306 | struct partial_page partial_def[PIPE_DEF_BUFFERS]; |
5307 | struct page *pages_def[PIPE_DEF_BUFFERS]; | |
2cadf913 | 5308 | struct splice_pipe_desc spd = { |
35f3d14d JA |
5309 | .pages = pages_def, |
5310 | .partial = partial_def, | |
047fe360 | 5311 | .nr_pages_max = PIPE_DEF_BUFFERS, |
2cadf913 SR |
5312 | .flags = flags, |
5313 | .ops = &buffer_pipe_buf_ops, | |
5314 | .spd_release = buffer_spd_release, | |
5315 | }; | |
5316 | struct buffer_ref *ref; | |
93459c6c | 5317 | int entries, size, i; |
6de58e62 | 5318 | ssize_t ret; |
2cadf913 | 5319 | |
6de58e62 SRRH |
5320 | mutex_lock(&trace_types_lock); |
5321 | ||
5322 | #ifdef CONFIG_TRACER_MAX_TRACE | |
5323 | if (iter->snapshot && iter->tr->current_trace->use_max_tr) { | |
5324 | ret = -EBUSY; | |
5325 | goto out; | |
5326 | } | |
5327 | #endif | |
5328 | ||
5329 | if (splice_grow_spd(pipe, &spd)) { | |
5330 | ret = -ENOMEM; | |
5331 | goto out; | |
5332 | } | |
35f3d14d | 5333 | |
93cfb3c9 | 5334 | if (*ppos & (PAGE_SIZE - 1)) { |
35f3d14d JA |
5335 | ret = -EINVAL; |
5336 | goto out; | |
93cfb3c9 LJ |
5337 | } |
5338 | ||
5339 | if (len & (PAGE_SIZE - 1)) { | |
35f3d14d JA |
5340 | if (len < PAGE_SIZE) { |
5341 | ret = -EINVAL; | |
5342 | goto out; | |
5343 | } | |
93cfb3c9 LJ |
5344 | len &= PAGE_MASK; |
5345 | } | |
5346 | ||
cc60cdc9 SR |
5347 | again: |
5348 | trace_access_lock(iter->cpu_file); | |
12883efb | 5349 | entries = ring_buffer_entries_cpu(iter->trace_buffer->buffer, iter->cpu_file); |
93459c6c | 5350 | |
a786c06d | 5351 | for (i = 0; i < spd.nr_pages_max && len && entries; i++, len -= PAGE_SIZE) { |
2cadf913 SR |
5352 | struct page *page; |
5353 | int r; | |
5354 | ||
5355 | ref = kzalloc(sizeof(*ref), GFP_KERNEL); | |
5356 | if (!ref) | |
5357 | break; | |
5358 | ||
7267fa68 | 5359 | ref->ref = 1; |
12883efb | 5360 | ref->buffer = iter->trace_buffer->buffer; |
cc60cdc9 | 5361 | ref->page = ring_buffer_alloc_read_page(ref->buffer, iter->cpu_file); |
2cadf913 SR |
5362 | if (!ref->page) { |
5363 | kfree(ref); | |
5364 | break; | |
5365 | } | |
5366 | ||
5367 | r = ring_buffer_read_page(ref->buffer, &ref->page, | |
cc60cdc9 | 5368 | len, iter->cpu_file, 1); |
2cadf913 | 5369 | if (r < 0) { |
7ea59064 | 5370 | ring_buffer_free_read_page(ref->buffer, ref->page); |
2cadf913 SR |
5371 | kfree(ref); |
5372 | break; | |
5373 | } | |
5374 | ||
5375 | /* | |
5376 | * zero out any left over data, this is going to | |
5377 | * user land. | |
5378 | */ | |
5379 | size = ring_buffer_page_len(ref->page); | |
5380 | if (size < PAGE_SIZE) | |
5381 | memset(ref->page + size, 0, PAGE_SIZE - size); | |
5382 | ||
5383 | page = virt_to_page(ref->page); | |
5384 | ||
5385 | spd.pages[i] = page; | |
5386 | spd.partial[i].len = PAGE_SIZE; | |
5387 | spd.partial[i].offset = 0; | |
5388 | spd.partial[i].private = (unsigned long)ref; | |
5389 | spd.nr_pages++; | |
93cfb3c9 | 5390 | *ppos += PAGE_SIZE; |
93459c6c | 5391 | |
12883efb | 5392 | entries = ring_buffer_entries_cpu(iter->trace_buffer->buffer, iter->cpu_file); |
2cadf913 SR |
5393 | } |
5394 | ||
cc60cdc9 | 5395 | trace_access_unlock(iter->cpu_file); |
2cadf913 SR |
5396 | spd.nr_pages = i; |
5397 | ||
5398 | /* did we read anything? */ | |
5399 | if (!spd.nr_pages) { | |
cc60cdc9 | 5400 | if ((file->f_flags & O_NONBLOCK) || (flags & SPLICE_F_NONBLOCK)) { |
2cadf913 | 5401 | ret = -EAGAIN; |
cc60cdc9 SR |
5402 | goto out; |
5403 | } | |
6de58e62 | 5404 | mutex_unlock(&trace_types_lock); |
b1169cc6 | 5405 | wait_on_pipe(iter); |
6de58e62 | 5406 | mutex_lock(&trace_types_lock); |
cc60cdc9 SR |
5407 | if (signal_pending(current)) { |
5408 | ret = -EINTR; | |
5409 | goto out; | |
5410 | } | |
5411 | goto again; | |
2cadf913 SR |
5412 | } |
5413 | ||
5414 | ret = splice_to_pipe(pipe, &spd); | |
047fe360 | 5415 | splice_shrink_spd(&spd); |
35f3d14d | 5416 | out: |
6de58e62 SRRH |
5417 | mutex_unlock(&trace_types_lock); |
5418 | ||
2cadf913 SR |
5419 | return ret; |
5420 | } | |
5421 | ||
5422 | static const struct file_operations tracing_buffers_fops = { | |
5423 | .open = tracing_buffers_open, | |
5424 | .read = tracing_buffers_read, | |
cc60cdc9 | 5425 | .poll = tracing_buffers_poll, |
2cadf913 SR |
5426 | .release = tracing_buffers_release, |
5427 | .splice_read = tracing_buffers_splice_read, | |
5428 | .llseek = no_llseek, | |
5429 | }; | |
5430 | ||
c8d77183 SR |
5431 | static ssize_t |
5432 | tracing_stats_read(struct file *filp, char __user *ubuf, | |
5433 | size_t count, loff_t *ppos) | |
5434 | { | |
4d3435b8 ON |
5435 | struct inode *inode = file_inode(filp); |
5436 | struct trace_array *tr = inode->i_private; | |
12883efb | 5437 | struct trace_buffer *trace_buf = &tr->trace_buffer; |
4d3435b8 | 5438 | int cpu = tracing_get_cpu(inode); |
c8d77183 SR |
5439 | struct trace_seq *s; |
5440 | unsigned long cnt; | |
c64e148a VN |
5441 | unsigned long long t; |
5442 | unsigned long usec_rem; | |
c8d77183 | 5443 | |
e4f2d10f | 5444 | s = kmalloc(sizeof(*s), GFP_KERNEL); |
c8d77183 | 5445 | if (!s) |
a646365c | 5446 | return -ENOMEM; |
c8d77183 SR |
5447 | |
5448 | trace_seq_init(s); | |
5449 | ||
12883efb | 5450 | cnt = ring_buffer_entries_cpu(trace_buf->buffer, cpu); |
c8d77183 SR |
5451 | trace_seq_printf(s, "entries: %ld\n", cnt); |
5452 | ||
12883efb | 5453 | cnt = ring_buffer_overrun_cpu(trace_buf->buffer, cpu); |
c8d77183 SR |
5454 | trace_seq_printf(s, "overrun: %ld\n", cnt); |
5455 | ||
12883efb | 5456 | cnt = ring_buffer_commit_overrun_cpu(trace_buf->buffer, cpu); |
c8d77183 SR |
5457 | trace_seq_printf(s, "commit overrun: %ld\n", cnt); |
5458 | ||
12883efb | 5459 | cnt = ring_buffer_bytes_cpu(trace_buf->buffer, cpu); |
c64e148a VN |
5460 | trace_seq_printf(s, "bytes: %ld\n", cnt); |
5461 | ||
58e8eedf | 5462 | if (trace_clocks[tr->clock_id].in_ns) { |
11043d8b | 5463 | /* local or global for trace_clock */ |
12883efb | 5464 | t = ns2usecs(ring_buffer_oldest_event_ts(trace_buf->buffer, cpu)); |
11043d8b YY |
5465 | usec_rem = do_div(t, USEC_PER_SEC); |
5466 | trace_seq_printf(s, "oldest event ts: %5llu.%06lu\n", | |
5467 | t, usec_rem); | |
5468 | ||
12883efb | 5469 | t = ns2usecs(ring_buffer_time_stamp(trace_buf->buffer, cpu)); |
11043d8b YY |
5470 | usec_rem = do_div(t, USEC_PER_SEC); |
5471 | trace_seq_printf(s, "now ts: %5llu.%06lu\n", t, usec_rem); | |
5472 | } else { | |
5473 | /* counter or tsc mode for trace_clock */ | |
5474 | trace_seq_printf(s, "oldest event ts: %llu\n", | |
12883efb | 5475 | ring_buffer_oldest_event_ts(trace_buf->buffer, cpu)); |
c64e148a | 5476 | |
11043d8b | 5477 | trace_seq_printf(s, "now ts: %llu\n", |
12883efb | 5478 | ring_buffer_time_stamp(trace_buf->buffer, cpu)); |
11043d8b | 5479 | } |
c64e148a | 5480 | |
12883efb | 5481 | cnt = ring_buffer_dropped_events_cpu(trace_buf->buffer, cpu); |
884bfe89 SP |
5482 | trace_seq_printf(s, "dropped events: %ld\n", cnt); |
5483 | ||
12883efb | 5484 | cnt = ring_buffer_read_events_cpu(trace_buf->buffer, cpu); |
ad964704 SRRH |
5485 | trace_seq_printf(s, "read events: %ld\n", cnt); |
5486 | ||
c8d77183 SR |
5487 | count = simple_read_from_buffer(ubuf, count, ppos, s->buffer, s->len); |
5488 | ||
5489 | kfree(s); | |
5490 | ||
5491 | return count; | |
5492 | } | |
5493 | ||
5494 | static const struct file_operations tracing_stats_fops = { | |
4d3435b8 | 5495 | .open = tracing_open_generic_tr, |
c8d77183 | 5496 | .read = tracing_stats_read, |
b444786f | 5497 | .llseek = generic_file_llseek, |
4d3435b8 | 5498 | .release = tracing_release_generic_tr, |
c8d77183 SR |
5499 | }; |
5500 | ||
bc0c38d1 SR |
5501 | #ifdef CONFIG_DYNAMIC_FTRACE |
5502 | ||
b807c3d0 SR |
5503 | int __weak ftrace_arch_read_dyn_info(char *buf, int size) |
5504 | { | |
5505 | return 0; | |
5506 | } | |
5507 | ||
bc0c38d1 | 5508 | static ssize_t |
b807c3d0 | 5509 | tracing_read_dyn_info(struct file *filp, char __user *ubuf, |
bc0c38d1 SR |
5510 | size_t cnt, loff_t *ppos) |
5511 | { | |
a26a2a27 SR |
5512 | static char ftrace_dyn_info_buffer[1024]; |
5513 | static DEFINE_MUTEX(dyn_info_mutex); | |
bc0c38d1 | 5514 | unsigned long *p = filp->private_data; |
b807c3d0 | 5515 | char *buf = ftrace_dyn_info_buffer; |
a26a2a27 | 5516 | int size = ARRAY_SIZE(ftrace_dyn_info_buffer); |
bc0c38d1 SR |
5517 | int r; |
5518 | ||
b807c3d0 SR |
5519 | mutex_lock(&dyn_info_mutex); |
5520 | r = sprintf(buf, "%ld ", *p); | |
4bf39a94 | 5521 | |
a26a2a27 | 5522 | r += ftrace_arch_read_dyn_info(buf+r, (size-1)-r); |
b807c3d0 SR |
5523 | buf[r++] = '\n'; |
5524 | ||
5525 | r = simple_read_from_buffer(ubuf, cnt, ppos, buf, r); | |
5526 | ||
5527 | mutex_unlock(&dyn_info_mutex); | |
5528 | ||
5529 | return r; | |
bc0c38d1 SR |
5530 | } |
5531 | ||
5e2336a0 | 5532 | static const struct file_operations tracing_dyn_info_fops = { |
4bf39a94 | 5533 | .open = tracing_open_generic, |
b807c3d0 | 5534 | .read = tracing_read_dyn_info, |
b444786f | 5535 | .llseek = generic_file_llseek, |
bc0c38d1 | 5536 | }; |
77fd5c15 | 5537 | #endif /* CONFIG_DYNAMIC_FTRACE */ |
bc0c38d1 | 5538 | |
77fd5c15 SRRH |
5539 | #if defined(CONFIG_TRACER_SNAPSHOT) && defined(CONFIG_DYNAMIC_FTRACE) |
5540 | static void | |
5541 | ftrace_snapshot(unsigned long ip, unsigned long parent_ip, void **data) | |
5542 | { | |
5543 | tracing_snapshot(); | |
5544 | } | |
bc0c38d1 | 5545 | |
77fd5c15 SRRH |
5546 | static void |
5547 | ftrace_count_snapshot(unsigned long ip, unsigned long parent_ip, void **data) | |
bc0c38d1 | 5548 | { |
77fd5c15 SRRH |
5549 | unsigned long *count = (long *)data; |
5550 | ||
5551 | if (!*count) | |
5552 | return; | |
bc0c38d1 | 5553 | |
77fd5c15 SRRH |
5554 | if (*count != -1) |
5555 | (*count)--; | |
5556 | ||
5557 | tracing_snapshot(); | |
5558 | } | |
5559 | ||
5560 | static int | |
5561 | ftrace_snapshot_print(struct seq_file *m, unsigned long ip, | |
5562 | struct ftrace_probe_ops *ops, void *data) | |
5563 | { | |
5564 | long count = (long)data; | |
5565 | ||
5566 | seq_printf(m, "%ps:", (void *)ip); | |
5567 | ||
5568 | seq_printf(m, "snapshot"); | |
5569 | ||
5570 | if (count == -1) | |
5571 | seq_printf(m, ":unlimited\n"); | |
5572 | else | |
5573 | seq_printf(m, ":count=%ld\n", count); | |
5574 | ||
5575 | return 0; | |
5576 | } | |
5577 | ||
5578 | static struct ftrace_probe_ops snapshot_probe_ops = { | |
5579 | .func = ftrace_snapshot, | |
5580 | .print = ftrace_snapshot_print, | |
5581 | }; | |
5582 | ||
5583 | static struct ftrace_probe_ops snapshot_count_probe_ops = { | |
5584 | .func = ftrace_count_snapshot, | |
5585 | .print = ftrace_snapshot_print, | |
5586 | }; | |
5587 | ||
5588 | static int | |
5589 | ftrace_trace_snapshot_callback(struct ftrace_hash *hash, | |
5590 | char *glob, char *cmd, char *param, int enable) | |
5591 | { | |
5592 | struct ftrace_probe_ops *ops; | |
5593 | void *count = (void *)-1; | |
5594 | char *number; | |
5595 | int ret; | |
5596 | ||
5597 | /* hash funcs only work with set_ftrace_filter */ | |
5598 | if (!enable) | |
5599 | return -EINVAL; | |
5600 | ||
5601 | ops = param ? &snapshot_count_probe_ops : &snapshot_probe_ops; | |
5602 | ||
5603 | if (glob[0] == '!') { | |
5604 | unregister_ftrace_function_probe_func(glob+1, ops); | |
5605 | return 0; | |
5606 | } | |
5607 | ||
5608 | if (!param) | |
5609 | goto out_reg; | |
5610 | ||
5611 | number = strsep(¶m, ":"); | |
5612 | ||
5613 | if (!strlen(number)) | |
5614 | goto out_reg; | |
5615 | ||
5616 | /* | |
5617 | * We use the callback data field (which is a pointer) | |
5618 | * as our counter. | |
5619 | */ | |
5620 | ret = kstrtoul(number, 0, (unsigned long *)&count); | |
5621 | if (ret) | |
5622 | return ret; | |
5623 | ||
5624 | out_reg: | |
5625 | ret = register_ftrace_function_probe(glob, ops, count); | |
5626 | ||
5627 | if (ret >= 0) | |
5628 | alloc_snapshot(&global_trace); | |
5629 | ||
5630 | return ret < 0 ? ret : 0; | |
5631 | } | |
5632 | ||
5633 | static struct ftrace_func_command ftrace_snapshot_cmd = { | |
5634 | .name = "snapshot", | |
5635 | .func = ftrace_trace_snapshot_callback, | |
5636 | }; | |
5637 | ||
38de93ab | 5638 | static __init int register_snapshot_cmd(void) |
77fd5c15 SRRH |
5639 | { |
5640 | return register_ftrace_command(&ftrace_snapshot_cmd); | |
5641 | } | |
5642 | #else | |
38de93ab | 5643 | static inline __init int register_snapshot_cmd(void) { return 0; } |
77fd5c15 | 5644 | #endif /* defined(CONFIG_TRACER_SNAPSHOT) && defined(CONFIG_DYNAMIC_FTRACE) */ |
bc0c38d1 | 5645 | |
2b6080f2 | 5646 | struct dentry *tracing_init_dentry_tr(struct trace_array *tr) |
bc0c38d1 | 5647 | { |
2b6080f2 SR |
5648 | if (tr->dir) |
5649 | return tr->dir; | |
bc0c38d1 | 5650 | |
3e1f60b8 FW |
5651 | if (!debugfs_initialized()) |
5652 | return NULL; | |
5653 | ||
2b6080f2 SR |
5654 | if (tr->flags & TRACE_ARRAY_FL_GLOBAL) |
5655 | tr->dir = debugfs_create_dir("tracing", NULL); | |
bc0c38d1 | 5656 | |
687c878a J |
5657 | if (!tr->dir) |
5658 | pr_warn_once("Could not create debugfs directory 'tracing'\n"); | |
bc0c38d1 | 5659 | |
2b6080f2 | 5660 | return tr->dir; |
bc0c38d1 SR |
5661 | } |
5662 | ||
2b6080f2 SR |
5663 | struct dentry *tracing_init_dentry(void) |
5664 | { | |
5665 | return tracing_init_dentry_tr(&global_trace); | |
5666 | } | |
b04cc6b1 | 5667 | |
2b6080f2 | 5668 | static struct dentry *tracing_dentry_percpu(struct trace_array *tr, int cpu) |
b04cc6b1 | 5669 | { |
b04cc6b1 FW |
5670 | struct dentry *d_tracer; |
5671 | ||
2b6080f2 SR |
5672 | if (tr->percpu_dir) |
5673 | return tr->percpu_dir; | |
b04cc6b1 | 5674 | |
2b6080f2 | 5675 | d_tracer = tracing_init_dentry_tr(tr); |
b04cc6b1 FW |
5676 | if (!d_tracer) |
5677 | return NULL; | |
5678 | ||
2b6080f2 | 5679 | tr->percpu_dir = debugfs_create_dir("per_cpu", d_tracer); |
b04cc6b1 | 5680 | |
2b6080f2 SR |
5681 | WARN_ONCE(!tr->percpu_dir, |
5682 | "Could not create debugfs directory 'per_cpu/%d'\n", cpu); | |
b04cc6b1 | 5683 | |
2b6080f2 | 5684 | return tr->percpu_dir; |
b04cc6b1 FW |
5685 | } |
5686 | ||
649e9c70 ON |
5687 | static struct dentry * |
5688 | trace_create_cpu_file(const char *name, umode_t mode, struct dentry *parent, | |
5689 | void *data, long cpu, const struct file_operations *fops) | |
5690 | { | |
5691 | struct dentry *ret = trace_create_file(name, mode, parent, data, fops); | |
5692 | ||
5693 | if (ret) /* See tracing_get_cpu() */ | |
5694 | ret->d_inode->i_cdev = (void *)(cpu + 1); | |
5695 | return ret; | |
5696 | } | |
5697 | ||
2b6080f2 SR |
5698 | static void |
5699 | tracing_init_debugfs_percpu(struct trace_array *tr, long cpu) | |
b04cc6b1 | 5700 | { |
2b6080f2 | 5701 | struct dentry *d_percpu = tracing_dentry_percpu(tr, cpu); |
5452af66 | 5702 | struct dentry *d_cpu; |
dd49a38c | 5703 | char cpu_dir[30]; /* 30 characters should be more than enough */ |
b04cc6b1 | 5704 | |
0a3d7ce7 NK |
5705 | if (!d_percpu) |
5706 | return; | |
5707 | ||
dd49a38c | 5708 | snprintf(cpu_dir, 30, "cpu%ld", cpu); |
8656e7a2 FW |
5709 | d_cpu = debugfs_create_dir(cpu_dir, d_percpu); |
5710 | if (!d_cpu) { | |
5711 | pr_warning("Could not create debugfs '%s' entry\n", cpu_dir); | |
5712 | return; | |
5713 | } | |
b04cc6b1 | 5714 | |
8656e7a2 | 5715 | /* per cpu trace_pipe */ |
649e9c70 | 5716 | trace_create_cpu_file("trace_pipe", 0444, d_cpu, |
15544209 | 5717 | tr, cpu, &tracing_pipe_fops); |
b04cc6b1 FW |
5718 | |
5719 | /* per cpu trace */ | |
649e9c70 | 5720 | trace_create_cpu_file("trace", 0644, d_cpu, |
6484c71c | 5721 | tr, cpu, &tracing_fops); |
7f96f93f | 5722 | |
649e9c70 | 5723 | trace_create_cpu_file("trace_pipe_raw", 0444, d_cpu, |
46ef2be0 | 5724 | tr, cpu, &tracing_buffers_fops); |
7f96f93f | 5725 | |
649e9c70 | 5726 | trace_create_cpu_file("stats", 0444, d_cpu, |
4d3435b8 | 5727 | tr, cpu, &tracing_stats_fops); |
438ced17 | 5728 | |
649e9c70 | 5729 | trace_create_cpu_file("buffer_size_kb", 0444, d_cpu, |
0bc392ee | 5730 | tr, cpu, &tracing_entries_fops); |
f1affcaa SRRH |
5731 | |
5732 | #ifdef CONFIG_TRACER_SNAPSHOT | |
649e9c70 | 5733 | trace_create_cpu_file("snapshot", 0644, d_cpu, |
6484c71c | 5734 | tr, cpu, &snapshot_fops); |
6de58e62 | 5735 | |
649e9c70 | 5736 | trace_create_cpu_file("snapshot_raw", 0444, d_cpu, |
46ef2be0 | 5737 | tr, cpu, &snapshot_raw_fops); |
f1affcaa | 5738 | #endif |
b04cc6b1 FW |
5739 | } |
5740 | ||
60a11774 SR |
5741 | #ifdef CONFIG_FTRACE_SELFTEST |
5742 | /* Let selftest have access to static functions in this file */ | |
5743 | #include "trace_selftest.c" | |
5744 | #endif | |
5745 | ||
577b785f SR |
5746 | struct trace_option_dentry { |
5747 | struct tracer_opt *opt; | |
5748 | struct tracer_flags *flags; | |
2b6080f2 | 5749 | struct trace_array *tr; |
577b785f SR |
5750 | struct dentry *entry; |
5751 | }; | |
5752 | ||
5753 | static ssize_t | |
5754 | trace_options_read(struct file *filp, char __user *ubuf, size_t cnt, | |
5755 | loff_t *ppos) | |
5756 | { | |
5757 | struct trace_option_dentry *topt = filp->private_data; | |
5758 | char *buf; | |
5759 | ||
5760 | if (topt->flags->val & topt->opt->bit) | |
5761 | buf = "1\n"; | |
5762 | else | |
5763 | buf = "0\n"; | |
5764 | ||
5765 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, 2); | |
5766 | } | |
5767 | ||
5768 | static ssize_t | |
5769 | trace_options_write(struct file *filp, const char __user *ubuf, size_t cnt, | |
5770 | loff_t *ppos) | |
5771 | { | |
5772 | struct trace_option_dentry *topt = filp->private_data; | |
5773 | unsigned long val; | |
577b785f SR |
5774 | int ret; |
5775 | ||
22fe9b54 PH |
5776 | ret = kstrtoul_from_user(ubuf, cnt, 10, &val); |
5777 | if (ret) | |
577b785f SR |
5778 | return ret; |
5779 | ||
8d18eaaf LZ |
5780 | if (val != 0 && val != 1) |
5781 | return -EINVAL; | |
577b785f | 5782 | |
8d18eaaf | 5783 | if (!!(topt->flags->val & topt->opt->bit) != val) { |
577b785f | 5784 | mutex_lock(&trace_types_lock); |
8c1a49ae | 5785 | ret = __set_tracer_option(topt->tr, topt->flags, |
c757bea9 | 5786 | topt->opt, !val); |
577b785f SR |
5787 | mutex_unlock(&trace_types_lock); |
5788 | if (ret) | |
5789 | return ret; | |
577b785f SR |
5790 | } |
5791 | ||
5792 | *ppos += cnt; | |
5793 | ||
5794 | return cnt; | |
5795 | } | |
5796 | ||
5797 | ||
5798 | static const struct file_operations trace_options_fops = { | |
5799 | .open = tracing_open_generic, | |
5800 | .read = trace_options_read, | |
5801 | .write = trace_options_write, | |
b444786f | 5802 | .llseek = generic_file_llseek, |
577b785f SR |
5803 | }; |
5804 | ||
a8259075 SR |
5805 | static ssize_t |
5806 | trace_options_core_read(struct file *filp, char __user *ubuf, size_t cnt, | |
5807 | loff_t *ppos) | |
5808 | { | |
5809 | long index = (long)filp->private_data; | |
5810 | char *buf; | |
5811 | ||
5812 | if (trace_flags & (1 << index)) | |
5813 | buf = "1\n"; | |
5814 | else | |
5815 | buf = "0\n"; | |
5816 | ||
5817 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, 2); | |
5818 | } | |
5819 | ||
5820 | static ssize_t | |
5821 | trace_options_core_write(struct file *filp, const char __user *ubuf, size_t cnt, | |
5822 | loff_t *ppos) | |
5823 | { | |
2b6080f2 | 5824 | struct trace_array *tr = &global_trace; |
a8259075 | 5825 | long index = (long)filp->private_data; |
a8259075 SR |
5826 | unsigned long val; |
5827 | int ret; | |
5828 | ||
22fe9b54 PH |
5829 | ret = kstrtoul_from_user(ubuf, cnt, 10, &val); |
5830 | if (ret) | |
a8259075 SR |
5831 | return ret; |
5832 | ||
f2d84b65 | 5833 | if (val != 0 && val != 1) |
a8259075 | 5834 | return -EINVAL; |
69d34da2 SRRH |
5835 | |
5836 | mutex_lock(&trace_types_lock); | |
2b6080f2 | 5837 | ret = set_tracer_flag(tr, 1 << index, val); |
69d34da2 | 5838 | mutex_unlock(&trace_types_lock); |
a8259075 | 5839 | |
613f04a0 SRRH |
5840 | if (ret < 0) |
5841 | return ret; | |
5842 | ||
a8259075 SR |
5843 | *ppos += cnt; |
5844 | ||
5845 | return cnt; | |
5846 | } | |
5847 | ||
a8259075 SR |
5848 | static const struct file_operations trace_options_core_fops = { |
5849 | .open = tracing_open_generic, | |
5850 | .read = trace_options_core_read, | |
5851 | .write = trace_options_core_write, | |
b444786f | 5852 | .llseek = generic_file_llseek, |
a8259075 SR |
5853 | }; |
5854 | ||
5452af66 | 5855 | struct dentry *trace_create_file(const char *name, |
f4ae40a6 | 5856 | umode_t mode, |
5452af66 FW |
5857 | struct dentry *parent, |
5858 | void *data, | |
5859 | const struct file_operations *fops) | |
5860 | { | |
5861 | struct dentry *ret; | |
5862 | ||
5863 | ret = debugfs_create_file(name, mode, parent, data, fops); | |
5864 | if (!ret) | |
5865 | pr_warning("Could not create debugfs '%s' entry\n", name); | |
5866 | ||
5867 | return ret; | |
5868 | } | |
5869 | ||
5870 | ||
2b6080f2 | 5871 | static struct dentry *trace_options_init_dentry(struct trace_array *tr) |
a8259075 SR |
5872 | { |
5873 | struct dentry *d_tracer; | |
a8259075 | 5874 | |
2b6080f2 SR |
5875 | if (tr->options) |
5876 | return tr->options; | |
a8259075 | 5877 | |
2b6080f2 | 5878 | d_tracer = tracing_init_dentry_tr(tr); |
a8259075 SR |
5879 | if (!d_tracer) |
5880 | return NULL; | |
5881 | ||
2b6080f2 SR |
5882 | tr->options = debugfs_create_dir("options", d_tracer); |
5883 | if (!tr->options) { | |
a8259075 SR |
5884 | pr_warning("Could not create debugfs directory 'options'\n"); |
5885 | return NULL; | |
5886 | } | |
5887 | ||
2b6080f2 | 5888 | return tr->options; |
a8259075 SR |
5889 | } |
5890 | ||
577b785f | 5891 | static void |
2b6080f2 SR |
5892 | create_trace_option_file(struct trace_array *tr, |
5893 | struct trace_option_dentry *topt, | |
577b785f SR |
5894 | struct tracer_flags *flags, |
5895 | struct tracer_opt *opt) | |
5896 | { | |
5897 | struct dentry *t_options; | |
577b785f | 5898 | |
2b6080f2 | 5899 | t_options = trace_options_init_dentry(tr); |
577b785f SR |
5900 | if (!t_options) |
5901 | return; | |
5902 | ||
5903 | topt->flags = flags; | |
5904 | topt->opt = opt; | |
2b6080f2 | 5905 | topt->tr = tr; |
577b785f | 5906 | |
5452af66 | 5907 | topt->entry = trace_create_file(opt->name, 0644, t_options, topt, |
577b785f SR |
5908 | &trace_options_fops); |
5909 | ||
577b785f SR |
5910 | } |
5911 | ||
5912 | static struct trace_option_dentry * | |
2b6080f2 | 5913 | create_trace_option_files(struct trace_array *tr, struct tracer *tracer) |
577b785f SR |
5914 | { |
5915 | struct trace_option_dentry *topts; | |
5916 | struct tracer_flags *flags; | |
5917 | struct tracer_opt *opts; | |
5918 | int cnt; | |
5919 | ||
5920 | if (!tracer) | |
5921 | return NULL; | |
5922 | ||
5923 | flags = tracer->flags; | |
5924 | ||
5925 | if (!flags || !flags->opts) | |
5926 | return NULL; | |
5927 | ||
5928 | opts = flags->opts; | |
5929 | ||
5930 | for (cnt = 0; opts[cnt].name; cnt++) | |
5931 | ; | |
5932 | ||
0cfe8245 | 5933 | topts = kcalloc(cnt + 1, sizeof(*topts), GFP_KERNEL); |
577b785f SR |
5934 | if (!topts) |
5935 | return NULL; | |
5936 | ||
5937 | for (cnt = 0; opts[cnt].name; cnt++) | |
2b6080f2 | 5938 | create_trace_option_file(tr, &topts[cnt], flags, |
577b785f SR |
5939 | &opts[cnt]); |
5940 | ||
5941 | return topts; | |
5942 | } | |
5943 | ||
5944 | static void | |
5945 | destroy_trace_option_files(struct trace_option_dentry *topts) | |
5946 | { | |
5947 | int cnt; | |
5948 | ||
5949 | if (!topts) | |
5950 | return; | |
5951 | ||
5952 | for (cnt = 0; topts[cnt].opt; cnt++) { | |
5953 | if (topts[cnt].entry) | |
5954 | debugfs_remove(topts[cnt].entry); | |
5955 | } | |
5956 | ||
5957 | kfree(topts); | |
5958 | } | |
5959 | ||
a8259075 | 5960 | static struct dentry * |
2b6080f2 SR |
5961 | create_trace_option_core_file(struct trace_array *tr, |
5962 | const char *option, long index) | |
a8259075 SR |
5963 | { |
5964 | struct dentry *t_options; | |
a8259075 | 5965 | |
2b6080f2 | 5966 | t_options = trace_options_init_dentry(tr); |
a8259075 SR |
5967 | if (!t_options) |
5968 | return NULL; | |
5969 | ||
5452af66 | 5970 | return trace_create_file(option, 0644, t_options, (void *)index, |
a8259075 | 5971 | &trace_options_core_fops); |
a8259075 SR |
5972 | } |
5973 | ||
2b6080f2 | 5974 | static __init void create_trace_options_dir(struct trace_array *tr) |
a8259075 SR |
5975 | { |
5976 | struct dentry *t_options; | |
a8259075 SR |
5977 | int i; |
5978 | ||
2b6080f2 | 5979 | t_options = trace_options_init_dentry(tr); |
a8259075 SR |
5980 | if (!t_options) |
5981 | return; | |
5982 | ||
5452af66 | 5983 | for (i = 0; trace_options[i]; i++) |
2b6080f2 | 5984 | create_trace_option_core_file(tr, trace_options[i], i); |
a8259075 SR |
5985 | } |
5986 | ||
499e5470 SR |
5987 | static ssize_t |
5988 | rb_simple_read(struct file *filp, char __user *ubuf, | |
5989 | size_t cnt, loff_t *ppos) | |
5990 | { | |
348f0fc2 | 5991 | struct trace_array *tr = filp->private_data; |
499e5470 SR |
5992 | char buf[64]; |
5993 | int r; | |
5994 | ||
10246fa3 | 5995 | r = tracer_tracing_is_on(tr); |
499e5470 SR |
5996 | r = sprintf(buf, "%d\n", r); |
5997 | ||
5998 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, r); | |
5999 | } | |
6000 | ||
6001 | static ssize_t | |
6002 | rb_simple_write(struct file *filp, const char __user *ubuf, | |
6003 | size_t cnt, loff_t *ppos) | |
6004 | { | |
348f0fc2 | 6005 | struct trace_array *tr = filp->private_data; |
12883efb | 6006 | struct ring_buffer *buffer = tr->trace_buffer.buffer; |
499e5470 SR |
6007 | unsigned long val; |
6008 | int ret; | |
6009 | ||
6010 | ret = kstrtoul_from_user(ubuf, cnt, 10, &val); | |
6011 | if (ret) | |
6012 | return ret; | |
6013 | ||
6014 | if (buffer) { | |
2df8f8a6 SR |
6015 | mutex_lock(&trace_types_lock); |
6016 | if (val) { | |
10246fa3 | 6017 | tracer_tracing_on(tr); |
2b6080f2 SR |
6018 | if (tr->current_trace->start) |
6019 | tr->current_trace->start(tr); | |
2df8f8a6 | 6020 | } else { |
10246fa3 | 6021 | tracer_tracing_off(tr); |
2b6080f2 SR |
6022 | if (tr->current_trace->stop) |
6023 | tr->current_trace->stop(tr); | |
2df8f8a6 SR |
6024 | } |
6025 | mutex_unlock(&trace_types_lock); | |
499e5470 SR |
6026 | } |
6027 | ||
6028 | (*ppos)++; | |
6029 | ||
6030 | return cnt; | |
6031 | } | |
6032 | ||
6033 | static const struct file_operations rb_simple_fops = { | |
7b85af63 | 6034 | .open = tracing_open_generic_tr, |
499e5470 SR |
6035 | .read = rb_simple_read, |
6036 | .write = rb_simple_write, | |
7b85af63 | 6037 | .release = tracing_release_generic_tr, |
499e5470 SR |
6038 | .llseek = default_llseek, |
6039 | }; | |
6040 | ||
277ba044 SR |
6041 | struct dentry *trace_instance_dir; |
6042 | ||
6043 | static void | |
6044 | init_tracer_debugfs(struct trace_array *tr, struct dentry *d_tracer); | |
6045 | ||
55034cd6 SRRH |
6046 | static int |
6047 | allocate_trace_buffer(struct trace_array *tr, struct trace_buffer *buf, int size) | |
277ba044 SR |
6048 | { |
6049 | enum ring_buffer_flags rb_flags; | |
737223fb SRRH |
6050 | |
6051 | rb_flags = trace_flags & TRACE_ITER_OVERWRITE ? RB_FL_OVERWRITE : 0; | |
6052 | ||
dced341b SRRH |
6053 | buf->tr = tr; |
6054 | ||
55034cd6 SRRH |
6055 | buf->buffer = ring_buffer_alloc(size, rb_flags); |
6056 | if (!buf->buffer) | |
6057 | return -ENOMEM; | |
737223fb | 6058 | |
55034cd6 SRRH |
6059 | buf->data = alloc_percpu(struct trace_array_cpu); |
6060 | if (!buf->data) { | |
6061 | ring_buffer_free(buf->buffer); | |
6062 | return -ENOMEM; | |
6063 | } | |
737223fb | 6064 | |
737223fb SRRH |
6065 | /* Allocate the first page for all buffers */ |
6066 | set_buffer_entries(&tr->trace_buffer, | |
6067 | ring_buffer_size(tr->trace_buffer.buffer, 0)); | |
6068 | ||
55034cd6 SRRH |
6069 | return 0; |
6070 | } | |
737223fb | 6071 | |
55034cd6 SRRH |
6072 | static int allocate_trace_buffers(struct trace_array *tr, int size) |
6073 | { | |
6074 | int ret; | |
737223fb | 6075 | |
55034cd6 SRRH |
6076 | ret = allocate_trace_buffer(tr, &tr->trace_buffer, size); |
6077 | if (ret) | |
6078 | return ret; | |
737223fb | 6079 | |
55034cd6 SRRH |
6080 | #ifdef CONFIG_TRACER_MAX_TRACE |
6081 | ret = allocate_trace_buffer(tr, &tr->max_buffer, | |
6082 | allocate_snapshot ? size : 1); | |
6083 | if (WARN_ON(ret)) { | |
737223fb | 6084 | ring_buffer_free(tr->trace_buffer.buffer); |
55034cd6 SRRH |
6085 | free_percpu(tr->trace_buffer.data); |
6086 | return -ENOMEM; | |
6087 | } | |
6088 | tr->allocated_snapshot = allocate_snapshot; | |
737223fb | 6089 | |
55034cd6 SRRH |
6090 | /* |
6091 | * Only the top level trace array gets its snapshot allocated | |
6092 | * from the kernel command line. | |
6093 | */ | |
6094 | allocate_snapshot = false; | |
737223fb | 6095 | #endif |
55034cd6 | 6096 | return 0; |
737223fb SRRH |
6097 | } |
6098 | ||
6099 | static int new_instance_create(const char *name) | |
6100 | { | |
277ba044 SR |
6101 | struct trace_array *tr; |
6102 | int ret; | |
277ba044 SR |
6103 | |
6104 | mutex_lock(&trace_types_lock); | |
6105 | ||
6106 | ret = -EEXIST; | |
6107 | list_for_each_entry(tr, &ftrace_trace_arrays, list) { | |
6108 | if (tr->name && strcmp(tr->name, name) == 0) | |
6109 | goto out_unlock; | |
6110 | } | |
6111 | ||
6112 | ret = -ENOMEM; | |
6113 | tr = kzalloc(sizeof(*tr), GFP_KERNEL); | |
6114 | if (!tr) | |
6115 | goto out_unlock; | |
6116 | ||
6117 | tr->name = kstrdup(name, GFP_KERNEL); | |
6118 | if (!tr->name) | |
6119 | goto out_free_tr; | |
6120 | ||
ccfe9e42 AL |
6121 | if (!alloc_cpumask_var(&tr->tracing_cpumask, GFP_KERNEL)) |
6122 | goto out_free_tr; | |
6123 | ||
6124 | cpumask_copy(tr->tracing_cpumask, cpu_all_mask); | |
6125 | ||
277ba044 SR |
6126 | raw_spin_lock_init(&tr->start_lock); |
6127 | ||
0b9b12c1 SRRH |
6128 | tr->max_lock = (arch_spinlock_t)__ARCH_SPIN_LOCK_UNLOCKED; |
6129 | ||
277ba044 SR |
6130 | tr->current_trace = &nop_trace; |
6131 | ||
6132 | INIT_LIST_HEAD(&tr->systems); | |
6133 | INIT_LIST_HEAD(&tr->events); | |
6134 | ||
737223fb | 6135 | if (allocate_trace_buffers(tr, trace_buf_size) < 0) |
277ba044 SR |
6136 | goto out_free_tr; |
6137 | ||
277ba044 SR |
6138 | tr->dir = debugfs_create_dir(name, trace_instance_dir); |
6139 | if (!tr->dir) | |
6140 | goto out_free_tr; | |
6141 | ||
6142 | ret = event_trace_add_tracer(tr->dir, tr); | |
609e85a7 AL |
6143 | if (ret) { |
6144 | debugfs_remove_recursive(tr->dir); | |
277ba044 | 6145 | goto out_free_tr; |
609e85a7 | 6146 | } |
277ba044 SR |
6147 | |
6148 | init_tracer_debugfs(tr, tr->dir); | |
6149 | ||
6150 | list_add(&tr->list, &ftrace_trace_arrays); | |
6151 | ||
6152 | mutex_unlock(&trace_types_lock); | |
6153 | ||
6154 | return 0; | |
6155 | ||
6156 | out_free_tr: | |
12883efb SRRH |
6157 | if (tr->trace_buffer.buffer) |
6158 | ring_buffer_free(tr->trace_buffer.buffer); | |
ccfe9e42 | 6159 | free_cpumask_var(tr->tracing_cpumask); |
277ba044 SR |
6160 | kfree(tr->name); |
6161 | kfree(tr); | |
6162 | ||
6163 | out_unlock: | |
6164 | mutex_unlock(&trace_types_lock); | |
6165 | ||
6166 | return ret; | |
6167 | ||
6168 | } | |
6169 | ||
0c8916c3 SR |
6170 | static int instance_delete(const char *name) |
6171 | { | |
6172 | struct trace_array *tr; | |
6173 | int found = 0; | |
6174 | int ret; | |
6175 | ||
6176 | mutex_lock(&trace_types_lock); | |
6177 | ||
6178 | ret = -ENODEV; | |
6179 | list_for_each_entry(tr, &ftrace_trace_arrays, list) { | |
6180 | if (tr->name && strcmp(tr->name, name) == 0) { | |
6181 | found = 1; | |
6182 | break; | |
6183 | } | |
6184 | } | |
6185 | if (!found) | |
6186 | goto out_unlock; | |
6187 | ||
a695cb58 SRRH |
6188 | ret = -EBUSY; |
6189 | if (tr->ref) | |
6190 | goto out_unlock; | |
6191 | ||
0c8916c3 SR |
6192 | list_del(&tr->list); |
6193 | ||
6b450d25 | 6194 | tracing_set_nop(tr); |
0c8916c3 | 6195 | event_trace_del_tracer(tr); |
591dffda | 6196 | ftrace_destroy_function_files(tr); |
0c8916c3 | 6197 | debugfs_remove_recursive(tr->dir); |
12883efb SRRH |
6198 | free_percpu(tr->trace_buffer.data); |
6199 | ring_buffer_free(tr->trace_buffer.buffer); | |
0c8916c3 SR |
6200 | |
6201 | kfree(tr->name); | |
6202 | kfree(tr); | |
6203 | ||
6204 | ret = 0; | |
6205 | ||
6206 | out_unlock: | |
6207 | mutex_unlock(&trace_types_lock); | |
6208 | ||
6209 | return ret; | |
6210 | } | |
6211 | ||
277ba044 SR |
6212 | static int instance_mkdir (struct inode *inode, struct dentry *dentry, umode_t mode) |
6213 | { | |
6214 | struct dentry *parent; | |
6215 | int ret; | |
6216 | ||
6217 | /* Paranoid: Make sure the parent is the "instances" directory */ | |
6218 | parent = hlist_entry(inode->i_dentry.first, struct dentry, d_alias); | |
6219 | if (WARN_ON_ONCE(parent != trace_instance_dir)) | |
6220 | return -ENOENT; | |
6221 | ||
6222 | /* | |
6223 | * The inode mutex is locked, but debugfs_create_dir() will also | |
6224 | * take the mutex. As the instances directory can not be destroyed | |
6225 | * or changed in any other way, it is safe to unlock it, and | |
6226 | * let the dentry try. If two users try to make the same dir at | |
6227 | * the same time, then the new_instance_create() will determine the | |
6228 | * winner. | |
6229 | */ | |
6230 | mutex_unlock(&inode->i_mutex); | |
6231 | ||
6232 | ret = new_instance_create(dentry->d_iname); | |
6233 | ||
6234 | mutex_lock(&inode->i_mutex); | |
6235 | ||
6236 | return ret; | |
6237 | } | |
6238 | ||
0c8916c3 SR |
6239 | static int instance_rmdir(struct inode *inode, struct dentry *dentry) |
6240 | { | |
6241 | struct dentry *parent; | |
6242 | int ret; | |
6243 | ||
6244 | /* Paranoid: Make sure the parent is the "instances" directory */ | |
6245 | parent = hlist_entry(inode->i_dentry.first, struct dentry, d_alias); | |
6246 | if (WARN_ON_ONCE(parent != trace_instance_dir)) | |
6247 | return -ENOENT; | |
6248 | ||
6249 | /* The caller did a dget() on dentry */ | |
6250 | mutex_unlock(&dentry->d_inode->i_mutex); | |
6251 | ||
6252 | /* | |
6253 | * The inode mutex is locked, but debugfs_create_dir() will also | |
6254 | * take the mutex. As the instances directory can not be destroyed | |
6255 | * or changed in any other way, it is safe to unlock it, and | |
6256 | * let the dentry try. If two users try to make the same dir at | |
6257 | * the same time, then the instance_delete() will determine the | |
6258 | * winner. | |
6259 | */ | |
6260 | mutex_unlock(&inode->i_mutex); | |
6261 | ||
6262 | ret = instance_delete(dentry->d_iname); | |
6263 | ||
6264 | mutex_lock_nested(&inode->i_mutex, I_MUTEX_PARENT); | |
6265 | mutex_lock(&dentry->d_inode->i_mutex); | |
6266 | ||
6267 | return ret; | |
6268 | } | |
6269 | ||
277ba044 SR |
6270 | static const struct inode_operations instance_dir_inode_operations = { |
6271 | .lookup = simple_lookup, | |
6272 | .mkdir = instance_mkdir, | |
0c8916c3 | 6273 | .rmdir = instance_rmdir, |
277ba044 SR |
6274 | }; |
6275 | ||
6276 | static __init void create_trace_instances(struct dentry *d_tracer) | |
6277 | { | |
6278 | trace_instance_dir = debugfs_create_dir("instances", d_tracer); | |
6279 | if (WARN_ON(!trace_instance_dir)) | |
6280 | return; | |
6281 | ||
6282 | /* Hijack the dir inode operations, to allow mkdir */ | |
6283 | trace_instance_dir->d_inode->i_op = &instance_dir_inode_operations; | |
6284 | } | |
6285 | ||
2b6080f2 SR |
6286 | static void |
6287 | init_tracer_debugfs(struct trace_array *tr, struct dentry *d_tracer) | |
6288 | { | |
121aaee7 | 6289 | int cpu; |
2b6080f2 | 6290 | |
607e2ea1 SRRH |
6291 | trace_create_file("available_tracers", 0444, d_tracer, |
6292 | tr, &show_traces_fops); | |
6293 | ||
6294 | trace_create_file("current_tracer", 0644, d_tracer, | |
6295 | tr, &set_tracer_fops); | |
6296 | ||
ccfe9e42 AL |
6297 | trace_create_file("tracing_cpumask", 0644, d_tracer, |
6298 | tr, &tracing_cpumask_fops); | |
6299 | ||
2b6080f2 SR |
6300 | trace_create_file("trace_options", 0644, d_tracer, |
6301 | tr, &tracing_iter_fops); | |
6302 | ||
6303 | trace_create_file("trace", 0644, d_tracer, | |
6484c71c | 6304 | tr, &tracing_fops); |
2b6080f2 SR |
6305 | |
6306 | trace_create_file("trace_pipe", 0444, d_tracer, | |
15544209 | 6307 | tr, &tracing_pipe_fops); |
2b6080f2 SR |
6308 | |
6309 | trace_create_file("buffer_size_kb", 0644, d_tracer, | |
0bc392ee | 6310 | tr, &tracing_entries_fops); |
2b6080f2 SR |
6311 | |
6312 | trace_create_file("buffer_total_size_kb", 0444, d_tracer, | |
6313 | tr, &tracing_total_entries_fops); | |
6314 | ||
238ae93d | 6315 | trace_create_file("free_buffer", 0200, d_tracer, |
2b6080f2 SR |
6316 | tr, &tracing_free_buffer_fops); |
6317 | ||
6318 | trace_create_file("trace_marker", 0220, d_tracer, | |
6319 | tr, &tracing_mark_fops); | |
6320 | ||
6321 | trace_create_file("trace_clock", 0644, d_tracer, tr, | |
6322 | &trace_clock_fops); | |
6323 | ||
6324 | trace_create_file("tracing_on", 0644, d_tracer, | |
6484c71c | 6325 | tr, &rb_simple_fops); |
ce9bae55 | 6326 | |
6d9b3fa5 SRRH |
6327 | #ifdef CONFIG_TRACER_MAX_TRACE |
6328 | trace_create_file("tracing_max_latency", 0644, d_tracer, | |
6329 | &tr->max_latency, &tracing_max_lat_fops); | |
6330 | #endif | |
6331 | ||
591dffda SRRH |
6332 | if (ftrace_create_function_files(tr, d_tracer)) |
6333 | WARN(1, "Could not allocate function filter files"); | |
6334 | ||
ce9bae55 SRRH |
6335 | #ifdef CONFIG_TRACER_SNAPSHOT |
6336 | trace_create_file("snapshot", 0644, d_tracer, | |
6484c71c | 6337 | tr, &snapshot_fops); |
ce9bae55 | 6338 | #endif |
121aaee7 SRRH |
6339 | |
6340 | for_each_tracing_cpu(cpu) | |
6341 | tracing_init_debugfs_percpu(tr, cpu); | |
6342 | ||
2b6080f2 SR |
6343 | } |
6344 | ||
b5ad384e | 6345 | static __init int tracer_init_debugfs(void) |
bc0c38d1 SR |
6346 | { |
6347 | struct dentry *d_tracer; | |
bc0c38d1 | 6348 | |
7e53bd42 LJ |
6349 | trace_access_lock_init(); |
6350 | ||
bc0c38d1 | 6351 | d_tracer = tracing_init_dentry(); |
ed6f1c99 NK |
6352 | if (!d_tracer) |
6353 | return 0; | |
bc0c38d1 | 6354 | |
2b6080f2 | 6355 | init_tracer_debugfs(&global_trace, d_tracer); |
bc0c38d1 | 6356 | |
5452af66 FW |
6357 | trace_create_file("tracing_thresh", 0644, d_tracer, |
6358 | &tracing_thresh, &tracing_max_lat_fops); | |
a8259075 | 6359 | |
339ae5d3 | 6360 | trace_create_file("README", 0444, d_tracer, |
5452af66 FW |
6361 | NULL, &tracing_readme_fops); |
6362 | ||
69abe6a5 AP |
6363 | trace_create_file("saved_cmdlines", 0444, d_tracer, |
6364 | NULL, &tracing_saved_cmdlines_fops); | |
5bf9a1ee | 6365 | |
bc0c38d1 | 6366 | #ifdef CONFIG_DYNAMIC_FTRACE |
5452af66 FW |
6367 | trace_create_file("dyn_ftrace_total_info", 0444, d_tracer, |
6368 | &ftrace_update_tot_cnt, &tracing_dyn_info_fops); | |
bc0c38d1 | 6369 | #endif |
b04cc6b1 | 6370 | |
277ba044 | 6371 | create_trace_instances(d_tracer); |
5452af66 | 6372 | |
2b6080f2 | 6373 | create_trace_options_dir(&global_trace); |
b04cc6b1 | 6374 | |
b5ad384e | 6375 | return 0; |
bc0c38d1 SR |
6376 | } |
6377 | ||
3f5a54e3 SR |
6378 | static int trace_panic_handler(struct notifier_block *this, |
6379 | unsigned long event, void *unused) | |
6380 | { | |
944ac425 | 6381 | if (ftrace_dump_on_oops) |
cecbca96 | 6382 | ftrace_dump(ftrace_dump_on_oops); |
3f5a54e3 SR |
6383 | return NOTIFY_OK; |
6384 | } | |
6385 | ||
6386 | static struct notifier_block trace_panic_notifier = { | |
6387 | .notifier_call = trace_panic_handler, | |
6388 | .next = NULL, | |
6389 | .priority = 150 /* priority: INT_MAX >= x >= 0 */ | |
6390 | }; | |
6391 | ||
6392 | static int trace_die_handler(struct notifier_block *self, | |
6393 | unsigned long val, | |
6394 | void *data) | |
6395 | { | |
6396 | switch (val) { | |
6397 | case DIE_OOPS: | |
944ac425 | 6398 | if (ftrace_dump_on_oops) |
cecbca96 | 6399 | ftrace_dump(ftrace_dump_on_oops); |
3f5a54e3 SR |
6400 | break; |
6401 | default: | |
6402 | break; | |
6403 | } | |
6404 | return NOTIFY_OK; | |
6405 | } | |
6406 | ||
6407 | static struct notifier_block trace_die_notifier = { | |
6408 | .notifier_call = trace_die_handler, | |
6409 | .priority = 200 | |
6410 | }; | |
6411 | ||
6412 | /* | |
6413 | * printk is set to max of 1024, we really don't need it that big. | |
6414 | * Nothing should be printing 1000 characters anyway. | |
6415 | */ | |
6416 | #define TRACE_MAX_PRINT 1000 | |
6417 | ||
6418 | /* | |
6419 | * Define here KERN_TRACE so that we have one place to modify | |
6420 | * it if we decide to change what log level the ftrace dump | |
6421 | * should be at. | |
6422 | */ | |
428aee14 | 6423 | #define KERN_TRACE KERN_EMERG |
3f5a54e3 | 6424 | |
955b61e5 | 6425 | void |
3f5a54e3 SR |
6426 | trace_printk_seq(struct trace_seq *s) |
6427 | { | |
6428 | /* Probably should print a warning here. */ | |
bd6df187 J |
6429 | if (s->len >= TRACE_MAX_PRINT) |
6430 | s->len = TRACE_MAX_PRINT; | |
3f5a54e3 SR |
6431 | |
6432 | /* should be zero ended, but we are paranoid. */ | |
6433 | s->buffer[s->len] = 0; | |
6434 | ||
6435 | printk(KERN_TRACE "%s", s->buffer); | |
6436 | ||
f9520750 | 6437 | trace_seq_init(s); |
3f5a54e3 SR |
6438 | } |
6439 | ||
955b61e5 JW |
6440 | void trace_init_global_iter(struct trace_iterator *iter) |
6441 | { | |
6442 | iter->tr = &global_trace; | |
2b6080f2 | 6443 | iter->trace = iter->tr->current_trace; |
ae3b5093 | 6444 | iter->cpu_file = RING_BUFFER_ALL_CPUS; |
12883efb | 6445 | iter->trace_buffer = &global_trace.trace_buffer; |
b2f974d6 CS |
6446 | |
6447 | if (iter->trace && iter->trace->open) | |
6448 | iter->trace->open(iter); | |
6449 | ||
6450 | /* Annotate start of buffers if we had overruns */ | |
6451 | if (ring_buffer_overruns(iter->trace_buffer->buffer)) | |
6452 | iter->iter_flags |= TRACE_FILE_ANNOTATE; | |
6453 | ||
6454 | /* Output in nanoseconds only if we are using a clock in nanoseconds. */ | |
6455 | if (trace_clocks[iter->tr->clock_id].in_ns) | |
6456 | iter->iter_flags |= TRACE_FILE_TIME_IN_NS; | |
955b61e5 JW |
6457 | } |
6458 | ||
7fe70b57 | 6459 | void ftrace_dump(enum ftrace_dump_mode oops_dump_mode) |
3f5a54e3 | 6460 | { |
3f5a54e3 SR |
6461 | /* use static because iter can be a bit big for the stack */ |
6462 | static struct trace_iterator iter; | |
7fe70b57 | 6463 | static atomic_t dump_running; |
cf586b61 | 6464 | unsigned int old_userobj; |
d769041f SR |
6465 | unsigned long flags; |
6466 | int cnt = 0, cpu; | |
3f5a54e3 | 6467 | |
7fe70b57 SRRH |
6468 | /* Only allow one dump user at a time. */ |
6469 | if (atomic_inc_return(&dump_running) != 1) { | |
6470 | atomic_dec(&dump_running); | |
6471 | return; | |
6472 | } | |
3f5a54e3 | 6473 | |
7fe70b57 SRRH |
6474 | /* |
6475 | * Always turn off tracing when we dump. | |
6476 | * We don't need to show trace output of what happens | |
6477 | * between multiple crashes. | |
6478 | * | |
6479 | * If the user does a sysrq-z, then they can re-enable | |
6480 | * tracing with echo 1 > tracing_on. | |
6481 | */ | |
0ee6b6cf | 6482 | tracing_off(); |
cf586b61 | 6483 | |
7fe70b57 | 6484 | local_irq_save(flags); |
3f5a54e3 | 6485 | |
38dbe0b1 | 6486 | /* Simulate the iterator */ |
955b61e5 JW |
6487 | trace_init_global_iter(&iter); |
6488 | ||
d769041f | 6489 | for_each_tracing_cpu(cpu) { |
12883efb | 6490 | atomic_inc(&per_cpu_ptr(iter.tr->trace_buffer.data, cpu)->disabled); |
d769041f SR |
6491 | } |
6492 | ||
cf586b61 FW |
6493 | old_userobj = trace_flags & TRACE_ITER_SYM_USEROBJ; |
6494 | ||
b54d3de9 TE |
6495 | /* don't look at user memory in panic mode */ |
6496 | trace_flags &= ~TRACE_ITER_SYM_USEROBJ; | |
6497 | ||
cecbca96 FW |
6498 | switch (oops_dump_mode) { |
6499 | case DUMP_ALL: | |
ae3b5093 | 6500 | iter.cpu_file = RING_BUFFER_ALL_CPUS; |
cecbca96 FW |
6501 | break; |
6502 | case DUMP_ORIG: | |
6503 | iter.cpu_file = raw_smp_processor_id(); | |
6504 | break; | |
6505 | case DUMP_NONE: | |
6506 | goto out_enable; | |
6507 | default: | |
6508 | printk(KERN_TRACE "Bad dumping mode, switching to all CPUs dump\n"); | |
ae3b5093 | 6509 | iter.cpu_file = RING_BUFFER_ALL_CPUS; |
cecbca96 FW |
6510 | } |
6511 | ||
6512 | printk(KERN_TRACE "Dumping ftrace buffer:\n"); | |
3f5a54e3 | 6513 | |
7fe70b57 SRRH |
6514 | /* Did function tracer already get disabled? */ |
6515 | if (ftrace_is_dead()) { | |
6516 | printk("# WARNING: FUNCTION TRACING IS CORRUPTED\n"); | |
6517 | printk("# MAY BE MISSING FUNCTION EVENTS\n"); | |
6518 | } | |
6519 | ||
3f5a54e3 SR |
6520 | /* |
6521 | * We need to stop all tracing on all CPUS to read the | |
6522 | * the next buffer. This is a bit expensive, but is | |
6523 | * not done often. We fill all what we can read, | |
6524 | * and then release the locks again. | |
6525 | */ | |
6526 | ||
3f5a54e3 SR |
6527 | while (!trace_empty(&iter)) { |
6528 | ||
6529 | if (!cnt) | |
6530 | printk(KERN_TRACE "---------------------------------\n"); | |
6531 | ||
6532 | cnt++; | |
6533 | ||
6534 | /* reset all but tr, trace, and overruns */ | |
6535 | memset(&iter.seq, 0, | |
6536 | sizeof(struct trace_iterator) - | |
6537 | offsetof(struct trace_iterator, seq)); | |
6538 | iter.iter_flags |= TRACE_FILE_LAT_FMT; | |
6539 | iter.pos = -1; | |
6540 | ||
955b61e5 | 6541 | if (trace_find_next_entry_inc(&iter) != NULL) { |
74e7ff8c LJ |
6542 | int ret; |
6543 | ||
6544 | ret = print_trace_line(&iter); | |
6545 | if (ret != TRACE_TYPE_NO_CONSUME) | |
6546 | trace_consume(&iter); | |
3f5a54e3 | 6547 | } |
b892e5c8 | 6548 | touch_nmi_watchdog(); |
3f5a54e3 SR |
6549 | |
6550 | trace_printk_seq(&iter.seq); | |
6551 | } | |
6552 | ||
6553 | if (!cnt) | |
6554 | printk(KERN_TRACE " (ftrace buffer empty)\n"); | |
6555 | else | |
6556 | printk(KERN_TRACE "---------------------------------\n"); | |
6557 | ||
cecbca96 | 6558 | out_enable: |
7fe70b57 | 6559 | trace_flags |= old_userobj; |
cf586b61 | 6560 | |
7fe70b57 SRRH |
6561 | for_each_tracing_cpu(cpu) { |
6562 | atomic_dec(&per_cpu_ptr(iter.trace_buffer->data, cpu)->disabled); | |
cf586b61 | 6563 | } |
7fe70b57 | 6564 | atomic_dec(&dump_running); |
cd891ae0 | 6565 | local_irq_restore(flags); |
3f5a54e3 | 6566 | } |
a8eecf22 | 6567 | EXPORT_SYMBOL_GPL(ftrace_dump); |
cf586b61 | 6568 | |
3928a8a2 | 6569 | __init static int tracer_alloc_buffers(void) |
bc0c38d1 | 6570 | { |
73c5162a | 6571 | int ring_buf_size; |
9e01c1b7 | 6572 | int ret = -ENOMEM; |
4c11d7ae | 6573 | |
750912fa | 6574 | |
9e01c1b7 RR |
6575 | if (!alloc_cpumask_var(&tracing_buffer_mask, GFP_KERNEL)) |
6576 | goto out; | |
6577 | ||
ccfe9e42 | 6578 | if (!alloc_cpumask_var(&global_trace.tracing_cpumask, GFP_KERNEL)) |
9e01c1b7 | 6579 | goto out_free_buffer_mask; |
4c11d7ae | 6580 | |
07d777fe SR |
6581 | /* Only allocate trace_printk buffers if a trace_printk exists */ |
6582 | if (__stop___trace_bprintk_fmt != __start___trace_bprintk_fmt) | |
81698831 | 6583 | /* Must be called before global_trace.buffer is allocated */ |
07d777fe SR |
6584 | trace_printk_init_buffers(); |
6585 | ||
73c5162a SR |
6586 | /* To save memory, keep the ring buffer size to its minimum */ |
6587 | if (ring_buffer_expanded) | |
6588 | ring_buf_size = trace_buf_size; | |
6589 | else | |
6590 | ring_buf_size = 1; | |
6591 | ||
9e01c1b7 | 6592 | cpumask_copy(tracing_buffer_mask, cpu_possible_mask); |
ccfe9e42 | 6593 | cpumask_copy(global_trace.tracing_cpumask, cpu_all_mask); |
9e01c1b7 | 6594 | |
2b6080f2 SR |
6595 | raw_spin_lock_init(&global_trace.start_lock); |
6596 | ||
2c4a33ab SRRH |
6597 | /* Used for event triggers */ |
6598 | temp_buffer = ring_buffer_alloc(PAGE_SIZE, RB_FL_OVERWRITE); | |
6599 | if (!temp_buffer) | |
6600 | goto out_free_cpumask; | |
6601 | ||
9e01c1b7 | 6602 | /* TODO: make the number of buffers hot pluggable with CPUS */ |
737223fb | 6603 | if (allocate_trace_buffers(&global_trace, ring_buf_size) < 0) { |
3928a8a2 SR |
6604 | printk(KERN_ERR "tracer: failed to allocate ring buffer!\n"); |
6605 | WARN_ON(1); | |
2c4a33ab | 6606 | goto out_free_temp_buffer; |
4c11d7ae | 6607 | } |
a7603ff4 | 6608 | |
499e5470 SR |
6609 | if (global_trace.buffer_disabled) |
6610 | tracing_off(); | |
4c11d7ae | 6611 | |
bc0c38d1 SR |
6612 | trace_init_cmdlines(); |
6613 | ||
e1e232ca SR |
6614 | if (trace_boot_clock) { |
6615 | ret = tracing_set_clock(&global_trace, trace_boot_clock); | |
6616 | if (ret < 0) | |
6617 | pr_warning("Trace clock %s not defined, going back to default\n", | |
6618 | trace_boot_clock); | |
6619 | } | |
6620 | ||
ca164318 SRRH |
6621 | /* |
6622 | * register_tracer() might reference current_trace, so it | |
6623 | * needs to be set before we register anything. This is | |
6624 | * just a bootstrap of current_trace anyway. | |
6625 | */ | |
2b6080f2 SR |
6626 | global_trace.current_trace = &nop_trace; |
6627 | ||
0b9b12c1 SRRH |
6628 | global_trace.max_lock = (arch_spinlock_t)__ARCH_SPIN_LOCK_UNLOCKED; |
6629 | ||
4104d326 SRRH |
6630 | ftrace_init_global_array_ops(&global_trace); |
6631 | ||
ca164318 SRRH |
6632 | register_tracer(&nop_trace); |
6633 | ||
60a11774 SR |
6634 | /* All seems OK, enable tracing */ |
6635 | tracing_disabled = 0; | |
3928a8a2 | 6636 | |
3f5a54e3 SR |
6637 | atomic_notifier_chain_register(&panic_notifier_list, |
6638 | &trace_panic_notifier); | |
6639 | ||
6640 | register_die_notifier(&trace_die_notifier); | |
2fc1dfbe | 6641 | |
ae63b31e SR |
6642 | global_trace.flags = TRACE_ARRAY_FL_GLOBAL; |
6643 | ||
6644 | INIT_LIST_HEAD(&global_trace.systems); | |
6645 | INIT_LIST_HEAD(&global_trace.events); | |
6646 | list_add(&global_trace.list, &ftrace_trace_arrays); | |
6647 | ||
7bcfaf54 SR |
6648 | while (trace_boot_options) { |
6649 | char *option; | |
6650 | ||
6651 | option = strsep(&trace_boot_options, ","); | |
2b6080f2 | 6652 | trace_set_options(&global_trace, option); |
7bcfaf54 SR |
6653 | } |
6654 | ||
77fd5c15 SRRH |
6655 | register_snapshot_cmd(); |
6656 | ||
2fc1dfbe | 6657 | return 0; |
3f5a54e3 | 6658 | |
2c4a33ab SRRH |
6659 | out_free_temp_buffer: |
6660 | ring_buffer_free(temp_buffer); | |
9e01c1b7 | 6661 | out_free_cpumask: |
12883efb SRRH |
6662 | free_percpu(global_trace.trace_buffer.data); |
6663 | #ifdef CONFIG_TRACER_MAX_TRACE | |
6664 | free_percpu(global_trace.max_buffer.data); | |
6665 | #endif | |
ccfe9e42 | 6666 | free_cpumask_var(global_trace.tracing_cpumask); |
9e01c1b7 RR |
6667 | out_free_buffer_mask: |
6668 | free_cpumask_var(tracing_buffer_mask); | |
6669 | out: | |
6670 | return ret; | |
bc0c38d1 | 6671 | } |
b2821ae6 SR |
6672 | |
6673 | __init static int clear_boot_tracer(void) | |
6674 | { | |
6675 | /* | |
6676 | * The default tracer at boot buffer is an init section. | |
6677 | * This function is called in lateinit. If we did not | |
6678 | * find the boot tracer, then clear it out, to prevent | |
6679 | * later registration from accessing the buffer that is | |
6680 | * about to be freed. | |
6681 | */ | |
6682 | if (!default_bootup_tracer) | |
6683 | return 0; | |
6684 | ||
6685 | printk(KERN_INFO "ftrace bootup tracer '%s' not registered.\n", | |
6686 | default_bootup_tracer); | |
6687 | default_bootup_tracer = NULL; | |
6688 | ||
6689 | return 0; | |
6690 | } | |
6691 | ||
b5ad384e FW |
6692 | early_initcall(tracer_alloc_buffers); |
6693 | fs_initcall(tracer_init_debugfs); | |
b2821ae6 | 6694 | late_initcall(clear_boot_tracer); |