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Commit | Line | Data |
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bc0c38d1 SR |
1 | /* |
2 | * ring buffer based function tracer | |
3 | * | |
2b6080f2 | 4 | * Copyright (C) 2007-2012 Steven Rostedt <srostedt@redhat.com> |
bc0c38d1 SR |
5 | * Copyright (C) 2008 Ingo Molnar <mingo@redhat.com> |
6 | * | |
7 | * Originally taken from the RT patch by: | |
8 | * Arnaldo Carvalho de Melo <acme@redhat.com> | |
9 | * | |
10 | * Based on code from the latency_tracer, that is: | |
11 | * Copyright (C) 2004-2006 Ingo Molnar | |
6d49e352 | 12 | * Copyright (C) 2004 Nadia Yvette Chambers |
bc0c38d1 | 13 | */ |
2cadf913 | 14 | #include <linux/ring_buffer.h> |
273b281f | 15 | #include <generated/utsrelease.h> |
2cadf913 SR |
16 | #include <linux/stacktrace.h> |
17 | #include <linux/writeback.h> | |
bc0c38d1 SR |
18 | #include <linux/kallsyms.h> |
19 | #include <linux/seq_file.h> | |
3f5a54e3 | 20 | #include <linux/notifier.h> |
2cadf913 | 21 | #include <linux/irqflags.h> |
bc0c38d1 | 22 | #include <linux/debugfs.h> |
4c11d7ae | 23 | #include <linux/pagemap.h> |
bc0c38d1 SR |
24 | #include <linux/hardirq.h> |
25 | #include <linux/linkage.h> | |
26 | #include <linux/uaccess.h> | |
2cadf913 | 27 | #include <linux/kprobes.h> |
bc0c38d1 SR |
28 | #include <linux/ftrace.h> |
29 | #include <linux/module.h> | |
30 | #include <linux/percpu.h> | |
2cadf913 | 31 | #include <linux/splice.h> |
3f5a54e3 | 32 | #include <linux/kdebug.h> |
5f0c6c03 | 33 | #include <linux/string.h> |
7e53bd42 | 34 | #include <linux/rwsem.h> |
5a0e3ad6 | 35 | #include <linux/slab.h> |
bc0c38d1 SR |
36 | #include <linux/ctype.h> |
37 | #include <linux/init.h> | |
2a2cc8f7 | 38 | #include <linux/poll.h> |
b892e5c8 | 39 | #include <linux/nmi.h> |
bc0c38d1 | 40 | #include <linux/fs.h> |
8bd75c77 | 41 | #include <linux/sched/rt.h> |
86387f7e | 42 | |
bc0c38d1 | 43 | #include "trace.h" |
f0868d1e | 44 | #include "trace_output.h" |
bc0c38d1 | 45 | |
73c5162a SR |
46 | /* |
47 | * On boot up, the ring buffer is set to the minimum size, so that | |
48 | * we do not waste memory on systems that are not using tracing. | |
49 | */ | |
55034cd6 | 50 | bool ring_buffer_expanded; |
73c5162a | 51 | |
8e1b82e0 FW |
52 | /* |
53 | * We need to change this state when a selftest is running. | |
ff32504f FW |
54 | * A selftest will lurk into the ring-buffer to count the |
55 | * entries inserted during the selftest although some concurrent | |
5e1607a0 | 56 | * insertions into the ring-buffer such as trace_printk could occurred |
ff32504f FW |
57 | * at the same time, giving false positive or negative results. |
58 | */ | |
8e1b82e0 | 59 | static bool __read_mostly tracing_selftest_running; |
ff32504f | 60 | |
b2821ae6 SR |
61 | /* |
62 | * If a tracer is running, we do not want to run SELFTEST. | |
63 | */ | |
020e5f85 | 64 | bool __read_mostly tracing_selftest_disabled; |
b2821ae6 | 65 | |
adf9f195 FW |
66 | /* For tracers that don't implement custom flags */ |
67 | static struct tracer_opt dummy_tracer_opt[] = { | |
68 | { } | |
69 | }; | |
70 | ||
71 | static struct tracer_flags dummy_tracer_flags = { | |
72 | .val = 0, | |
73 | .opts = dummy_tracer_opt | |
74 | }; | |
75 | ||
76 | static int dummy_set_flag(u32 old_flags, u32 bit, int set) | |
77 | { | |
78 | return 0; | |
79 | } | |
0f048701 | 80 | |
7ffbd48d SR |
81 | /* |
82 | * To prevent the comm cache from being overwritten when no | |
83 | * tracing is active, only save the comm when a trace event | |
84 | * occurred. | |
85 | */ | |
86 | static DEFINE_PER_CPU(bool, trace_cmdline_save); | |
87 | ||
0f048701 SR |
88 | /* |
89 | * Kill all tracing for good (never come back). | |
90 | * It is initialized to 1 but will turn to zero if the initialization | |
91 | * of the tracer is successful. But that is the only place that sets | |
92 | * this back to zero. | |
93 | */ | |
4fd27358 | 94 | static int tracing_disabled = 1; |
0f048701 | 95 | |
9288f99a | 96 | DEFINE_PER_CPU(int, ftrace_cpu_disabled); |
d769041f | 97 | |
955b61e5 | 98 | cpumask_var_t __read_mostly tracing_buffer_mask; |
ab46428c | 99 | |
944ac425 SR |
100 | /* |
101 | * ftrace_dump_on_oops - variable to dump ftrace buffer on oops | |
102 | * | |
103 | * If there is an oops (or kernel panic) and the ftrace_dump_on_oops | |
104 | * is set, then ftrace_dump is called. This will output the contents | |
105 | * of the ftrace buffers to the console. This is very useful for | |
106 | * capturing traces that lead to crashes and outputing it to a | |
107 | * serial console. | |
108 | * | |
109 | * It is default off, but you can enable it with either specifying | |
110 | * "ftrace_dump_on_oops" in the kernel command line, or setting | |
cecbca96 FW |
111 | * /proc/sys/kernel/ftrace_dump_on_oops |
112 | * Set 1 if you want to dump buffers of all CPUs | |
113 | * Set 2 if you want to dump the buffer of the CPU that triggered oops | |
944ac425 | 114 | */ |
cecbca96 FW |
115 | |
116 | enum ftrace_dump_mode ftrace_dump_on_oops; | |
944ac425 | 117 | |
b2821ae6 SR |
118 | static int tracing_set_tracer(const char *buf); |
119 | ||
ee6c2c1b LZ |
120 | #define MAX_TRACER_SIZE 100 |
121 | static char bootup_tracer_buf[MAX_TRACER_SIZE] __initdata; | |
b2821ae6 | 122 | static char *default_bootup_tracer; |
d9e54076 | 123 | |
55034cd6 SRRH |
124 | static bool allocate_snapshot; |
125 | ||
1beee96b | 126 | static int __init set_cmdline_ftrace(char *str) |
d9e54076 | 127 | { |
67012ab1 | 128 | strlcpy(bootup_tracer_buf, str, MAX_TRACER_SIZE); |
b2821ae6 | 129 | default_bootup_tracer = bootup_tracer_buf; |
73c5162a | 130 | /* We are using ftrace early, expand it */ |
55034cd6 | 131 | ring_buffer_expanded = true; |
d9e54076 PZ |
132 | return 1; |
133 | } | |
1beee96b | 134 | __setup("ftrace=", set_cmdline_ftrace); |
d9e54076 | 135 | |
944ac425 SR |
136 | static int __init set_ftrace_dump_on_oops(char *str) |
137 | { | |
cecbca96 FW |
138 | if (*str++ != '=' || !*str) { |
139 | ftrace_dump_on_oops = DUMP_ALL; | |
140 | return 1; | |
141 | } | |
142 | ||
143 | if (!strcmp("orig_cpu", str)) { | |
144 | ftrace_dump_on_oops = DUMP_ORIG; | |
145 | return 1; | |
146 | } | |
147 | ||
148 | return 0; | |
944ac425 SR |
149 | } |
150 | __setup("ftrace_dump_on_oops", set_ftrace_dump_on_oops); | |
60a11774 | 151 | |
3209cff4 | 152 | static int __init boot_alloc_snapshot(char *str) |
55034cd6 SRRH |
153 | { |
154 | allocate_snapshot = true; | |
155 | /* We also need the main ring buffer expanded */ | |
156 | ring_buffer_expanded = true; | |
157 | return 1; | |
158 | } | |
3209cff4 | 159 | __setup("alloc_snapshot", boot_alloc_snapshot); |
55034cd6 | 160 | |
7bcfaf54 SR |
161 | |
162 | static char trace_boot_options_buf[MAX_TRACER_SIZE] __initdata; | |
163 | static char *trace_boot_options __initdata; | |
164 | ||
165 | static int __init set_trace_boot_options(char *str) | |
166 | { | |
67012ab1 | 167 | strlcpy(trace_boot_options_buf, str, MAX_TRACER_SIZE); |
7bcfaf54 SR |
168 | trace_boot_options = trace_boot_options_buf; |
169 | return 0; | |
170 | } | |
171 | __setup("trace_options=", set_trace_boot_options); | |
172 | ||
cf8e3474 | 173 | unsigned long long ns2usecs(cycle_t nsec) |
bc0c38d1 SR |
174 | { |
175 | nsec += 500; | |
176 | do_div(nsec, 1000); | |
177 | return nsec; | |
178 | } | |
179 | ||
4fcdae83 SR |
180 | /* |
181 | * The global_trace is the descriptor that holds the tracing | |
182 | * buffers for the live tracing. For each CPU, it contains | |
183 | * a link list of pages that will store trace entries. The | |
184 | * page descriptor of the pages in the memory is used to hold | |
185 | * the link list by linking the lru item in the page descriptor | |
186 | * to each of the pages in the buffer per CPU. | |
187 | * | |
188 | * For each active CPU there is a data field that holds the | |
189 | * pages for the buffer for that CPU. Each CPU has the same number | |
190 | * of pages allocated for its buffer. | |
191 | */ | |
bc0c38d1 SR |
192 | static struct trace_array global_trace; |
193 | ||
ae63b31e | 194 | LIST_HEAD(ftrace_trace_arrays); |
bc0c38d1 | 195 | |
e77405ad SR |
196 | int filter_current_check_discard(struct ring_buffer *buffer, |
197 | struct ftrace_event_call *call, void *rec, | |
eb02ce01 TZ |
198 | struct ring_buffer_event *event) |
199 | { | |
e77405ad | 200 | return filter_check_discard(call, rec, buffer, event); |
eb02ce01 | 201 | } |
17c873ec | 202 | EXPORT_SYMBOL_GPL(filter_current_check_discard); |
eb02ce01 | 203 | |
37886f6a SR |
204 | cycle_t ftrace_now(int cpu) |
205 | { | |
206 | u64 ts; | |
207 | ||
208 | /* Early boot up does not have a buffer yet */ | |
12883efb | 209 | if (!global_trace.trace_buffer.buffer) |
37886f6a SR |
210 | return trace_clock_local(); |
211 | ||
12883efb SRRH |
212 | ts = ring_buffer_time_stamp(global_trace.trace_buffer.buffer, cpu); |
213 | ring_buffer_normalize_time_stamp(global_trace.trace_buffer.buffer, cpu, &ts); | |
37886f6a SR |
214 | |
215 | return ts; | |
216 | } | |
bc0c38d1 | 217 | |
9036990d SR |
218 | int tracing_is_enabled(void) |
219 | { | |
0fb9656d | 220 | return tracing_is_on(); |
9036990d SR |
221 | } |
222 | ||
4fcdae83 | 223 | /* |
3928a8a2 SR |
224 | * trace_buf_size is the size in bytes that is allocated |
225 | * for a buffer. Note, the number of bytes is always rounded | |
226 | * to page size. | |
3f5a54e3 SR |
227 | * |
228 | * This number is purposely set to a low number of 16384. | |
229 | * If the dump on oops happens, it will be much appreciated | |
230 | * to not have to wait for all that output. Anyway this can be | |
231 | * boot time and run time configurable. | |
4fcdae83 | 232 | */ |
3928a8a2 | 233 | #define TRACE_BUF_SIZE_DEFAULT 1441792UL /* 16384 * 88 (sizeof(entry)) */ |
3f5a54e3 | 234 | |
3928a8a2 | 235 | static unsigned long trace_buf_size = TRACE_BUF_SIZE_DEFAULT; |
bc0c38d1 | 236 | |
4fcdae83 | 237 | /* trace_types holds a link list of available tracers. */ |
bc0c38d1 | 238 | static struct tracer *trace_types __read_mostly; |
4fcdae83 | 239 | |
4fcdae83 SR |
240 | /* |
241 | * trace_types_lock is used to protect the trace_types list. | |
4fcdae83 | 242 | */ |
bc0c38d1 | 243 | static DEFINE_MUTEX(trace_types_lock); |
4fcdae83 | 244 | |
7e53bd42 LJ |
245 | /* |
246 | * serialize the access of the ring buffer | |
247 | * | |
248 | * ring buffer serializes readers, but it is low level protection. | |
249 | * The validity of the events (which returns by ring_buffer_peek() ..etc) | |
250 | * are not protected by ring buffer. | |
251 | * | |
252 | * The content of events may become garbage if we allow other process consumes | |
253 | * these events concurrently: | |
254 | * A) the page of the consumed events may become a normal page | |
255 | * (not reader page) in ring buffer, and this page will be rewrited | |
256 | * by events producer. | |
257 | * B) The page of the consumed events may become a page for splice_read, | |
258 | * and this page will be returned to system. | |
259 | * | |
260 | * These primitives allow multi process access to different cpu ring buffer | |
261 | * concurrently. | |
262 | * | |
263 | * These primitives don't distinguish read-only and read-consume access. | |
264 | * Multi read-only access are also serialized. | |
265 | */ | |
266 | ||
267 | #ifdef CONFIG_SMP | |
268 | static DECLARE_RWSEM(all_cpu_access_lock); | |
269 | static DEFINE_PER_CPU(struct mutex, cpu_access_lock); | |
270 | ||
271 | static inline void trace_access_lock(int cpu) | |
272 | { | |
ae3b5093 | 273 | if (cpu == RING_BUFFER_ALL_CPUS) { |
7e53bd42 LJ |
274 | /* gain it for accessing the whole ring buffer. */ |
275 | down_write(&all_cpu_access_lock); | |
276 | } else { | |
277 | /* gain it for accessing a cpu ring buffer. */ | |
278 | ||
ae3b5093 | 279 | /* Firstly block other trace_access_lock(RING_BUFFER_ALL_CPUS). */ |
7e53bd42 LJ |
280 | down_read(&all_cpu_access_lock); |
281 | ||
282 | /* Secondly block other access to this @cpu ring buffer. */ | |
283 | mutex_lock(&per_cpu(cpu_access_lock, cpu)); | |
284 | } | |
285 | } | |
286 | ||
287 | static inline void trace_access_unlock(int cpu) | |
288 | { | |
ae3b5093 | 289 | if (cpu == RING_BUFFER_ALL_CPUS) { |
7e53bd42 LJ |
290 | up_write(&all_cpu_access_lock); |
291 | } else { | |
292 | mutex_unlock(&per_cpu(cpu_access_lock, cpu)); | |
293 | up_read(&all_cpu_access_lock); | |
294 | } | |
295 | } | |
296 | ||
297 | static inline void trace_access_lock_init(void) | |
298 | { | |
299 | int cpu; | |
300 | ||
301 | for_each_possible_cpu(cpu) | |
302 | mutex_init(&per_cpu(cpu_access_lock, cpu)); | |
303 | } | |
304 | ||
305 | #else | |
306 | ||
307 | static DEFINE_MUTEX(access_lock); | |
308 | ||
309 | static inline void trace_access_lock(int cpu) | |
310 | { | |
311 | (void)cpu; | |
312 | mutex_lock(&access_lock); | |
313 | } | |
314 | ||
315 | static inline void trace_access_unlock(int cpu) | |
316 | { | |
317 | (void)cpu; | |
318 | mutex_unlock(&access_lock); | |
319 | } | |
320 | ||
321 | static inline void trace_access_lock_init(void) | |
322 | { | |
323 | } | |
324 | ||
325 | #endif | |
326 | ||
ee6bce52 | 327 | /* trace_flags holds trace_options default values */ |
12ef7d44 | 328 | unsigned long trace_flags = TRACE_ITER_PRINT_PARENT | TRACE_ITER_PRINTK | |
a2a16d6a | 329 | TRACE_ITER_ANNOTATE | TRACE_ITER_CONTEXT_INFO | TRACE_ITER_SLEEP_TIME | |
77271ce4 | 330 | TRACE_ITER_GRAPH_TIME | TRACE_ITER_RECORD_CMD | TRACE_ITER_OVERWRITE | |
328df475 | 331 | TRACE_ITER_IRQ_INFO | TRACE_ITER_MARKERS | TRACE_ITER_FUNCTION; |
e7e2ee89 | 332 | |
499e5470 SR |
333 | /** |
334 | * tracing_on - enable tracing buffers | |
335 | * | |
336 | * This function enables tracing buffers that may have been | |
337 | * disabled with tracing_off. | |
338 | */ | |
339 | void tracing_on(void) | |
340 | { | |
12883efb SRRH |
341 | if (global_trace.trace_buffer.buffer) |
342 | ring_buffer_record_on(global_trace.trace_buffer.buffer); | |
499e5470 SR |
343 | /* |
344 | * This flag is only looked at when buffers haven't been | |
345 | * allocated yet. We don't really care about the race | |
346 | * between setting this flag and actually turning | |
347 | * on the buffer. | |
348 | */ | |
349 | global_trace.buffer_disabled = 0; | |
350 | } | |
351 | EXPORT_SYMBOL_GPL(tracing_on); | |
352 | ||
09ae7234 SRRH |
353 | /** |
354 | * __trace_puts - write a constant string into the trace buffer. | |
355 | * @ip: The address of the caller | |
356 | * @str: The constant string to write | |
357 | * @size: The size of the string. | |
358 | */ | |
359 | int __trace_puts(unsigned long ip, const char *str, int size) | |
360 | { | |
361 | struct ring_buffer_event *event; | |
362 | struct ring_buffer *buffer; | |
363 | struct print_entry *entry; | |
364 | unsigned long irq_flags; | |
365 | int alloc; | |
366 | ||
367 | alloc = sizeof(*entry) + size + 2; /* possible \n added */ | |
368 | ||
369 | local_save_flags(irq_flags); | |
370 | buffer = global_trace.trace_buffer.buffer; | |
371 | event = trace_buffer_lock_reserve(buffer, TRACE_PRINT, alloc, | |
372 | irq_flags, preempt_count()); | |
373 | if (!event) | |
374 | return 0; | |
375 | ||
376 | entry = ring_buffer_event_data(event); | |
377 | entry->ip = ip; | |
378 | ||
379 | memcpy(&entry->buf, str, size); | |
380 | ||
381 | /* Add a newline if necessary */ | |
382 | if (entry->buf[size - 1] != '\n') { | |
383 | entry->buf[size] = '\n'; | |
384 | entry->buf[size + 1] = '\0'; | |
385 | } else | |
386 | entry->buf[size] = '\0'; | |
387 | ||
388 | __buffer_unlock_commit(buffer, event); | |
389 | ||
390 | return size; | |
391 | } | |
392 | EXPORT_SYMBOL_GPL(__trace_puts); | |
393 | ||
394 | /** | |
395 | * __trace_bputs - write the pointer to a constant string into trace buffer | |
396 | * @ip: The address of the caller | |
397 | * @str: The constant string to write to the buffer to | |
398 | */ | |
399 | int __trace_bputs(unsigned long ip, const char *str) | |
400 | { | |
401 | struct ring_buffer_event *event; | |
402 | struct ring_buffer *buffer; | |
403 | struct bputs_entry *entry; | |
404 | unsigned long irq_flags; | |
405 | int size = sizeof(struct bputs_entry); | |
406 | ||
407 | local_save_flags(irq_flags); | |
408 | buffer = global_trace.trace_buffer.buffer; | |
409 | event = trace_buffer_lock_reserve(buffer, TRACE_BPUTS, size, | |
410 | irq_flags, preempt_count()); | |
411 | if (!event) | |
412 | return 0; | |
413 | ||
414 | entry = ring_buffer_event_data(event); | |
415 | entry->ip = ip; | |
416 | entry->str = str; | |
417 | ||
418 | __buffer_unlock_commit(buffer, event); | |
419 | ||
420 | return 1; | |
421 | } | |
422 | EXPORT_SYMBOL_GPL(__trace_bputs); | |
423 | ||
ad909e21 SRRH |
424 | #ifdef CONFIG_TRACER_SNAPSHOT |
425 | /** | |
426 | * trace_snapshot - take a snapshot of the current buffer. | |
427 | * | |
428 | * This causes a swap between the snapshot buffer and the current live | |
429 | * tracing buffer. You can use this to take snapshots of the live | |
430 | * trace when some condition is triggered, but continue to trace. | |
431 | * | |
432 | * Note, make sure to allocate the snapshot with either | |
433 | * a tracing_snapshot_alloc(), or by doing it manually | |
434 | * with: echo 1 > /sys/kernel/debug/tracing/snapshot | |
435 | * | |
436 | * If the snapshot buffer is not allocated, it will stop tracing. | |
437 | * Basically making a permanent snapshot. | |
438 | */ | |
439 | void tracing_snapshot(void) | |
440 | { | |
441 | struct trace_array *tr = &global_trace; | |
442 | struct tracer *tracer = tr->current_trace; | |
443 | unsigned long flags; | |
444 | ||
1b22e382 SRRH |
445 | if (in_nmi()) { |
446 | internal_trace_puts("*** SNAPSHOT CALLED FROM NMI CONTEXT ***\n"); | |
447 | internal_trace_puts("*** snapshot is being ignored ***\n"); | |
448 | return; | |
449 | } | |
450 | ||
ad909e21 | 451 | if (!tr->allocated_snapshot) { |
ca268da6 SRRH |
452 | internal_trace_puts("*** SNAPSHOT NOT ALLOCATED ***\n"); |
453 | internal_trace_puts("*** stopping trace here! ***\n"); | |
ad909e21 SRRH |
454 | tracing_off(); |
455 | return; | |
456 | } | |
457 | ||
458 | /* Note, snapshot can not be used when the tracer uses it */ | |
459 | if (tracer->use_max_tr) { | |
ca268da6 SRRH |
460 | internal_trace_puts("*** LATENCY TRACER ACTIVE ***\n"); |
461 | internal_trace_puts("*** Can not use snapshot (sorry) ***\n"); | |
ad909e21 SRRH |
462 | return; |
463 | } | |
464 | ||
465 | local_irq_save(flags); | |
466 | update_max_tr(tr, current, smp_processor_id()); | |
467 | local_irq_restore(flags); | |
468 | } | |
1b22e382 | 469 | EXPORT_SYMBOL_GPL(tracing_snapshot); |
ad909e21 SRRH |
470 | |
471 | static int resize_buffer_duplicate_size(struct trace_buffer *trace_buf, | |
472 | struct trace_buffer *size_buf, int cpu_id); | |
3209cff4 SRRH |
473 | static void set_buffer_entries(struct trace_buffer *buf, unsigned long val); |
474 | ||
475 | static int alloc_snapshot(struct trace_array *tr) | |
476 | { | |
477 | int ret; | |
478 | ||
479 | if (!tr->allocated_snapshot) { | |
480 | ||
481 | /* allocate spare buffer */ | |
482 | ret = resize_buffer_duplicate_size(&tr->max_buffer, | |
483 | &tr->trace_buffer, RING_BUFFER_ALL_CPUS); | |
484 | if (ret < 0) | |
485 | return ret; | |
486 | ||
487 | tr->allocated_snapshot = true; | |
488 | } | |
489 | ||
490 | return 0; | |
491 | } | |
492 | ||
493 | void free_snapshot(struct trace_array *tr) | |
494 | { | |
495 | /* | |
496 | * We don't free the ring buffer. instead, resize it because | |
497 | * The max_tr ring buffer has some state (e.g. ring->clock) and | |
498 | * we want preserve it. | |
499 | */ | |
500 | ring_buffer_resize(tr->max_buffer.buffer, 1, RING_BUFFER_ALL_CPUS); | |
501 | set_buffer_entries(&tr->max_buffer, 1); | |
502 | tracing_reset_online_cpus(&tr->max_buffer); | |
503 | tr->allocated_snapshot = false; | |
504 | } | |
ad909e21 SRRH |
505 | |
506 | /** | |
507 | * trace_snapshot_alloc - allocate and take a snapshot of the current buffer. | |
508 | * | |
509 | * This is similar to trace_snapshot(), but it will allocate the | |
510 | * snapshot buffer if it isn't already allocated. Use this only | |
511 | * where it is safe to sleep, as the allocation may sleep. | |
512 | * | |
513 | * This causes a swap between the snapshot buffer and the current live | |
514 | * tracing buffer. You can use this to take snapshots of the live | |
515 | * trace when some condition is triggered, but continue to trace. | |
516 | */ | |
517 | void tracing_snapshot_alloc(void) | |
518 | { | |
519 | struct trace_array *tr = &global_trace; | |
520 | int ret; | |
521 | ||
3209cff4 SRRH |
522 | ret = alloc_snapshot(tr); |
523 | if (WARN_ON(ret < 0)) | |
524 | return; | |
ad909e21 SRRH |
525 | |
526 | tracing_snapshot(); | |
527 | } | |
1b22e382 | 528 | EXPORT_SYMBOL_GPL(tracing_snapshot_alloc); |
ad909e21 SRRH |
529 | #else |
530 | void tracing_snapshot(void) | |
531 | { | |
532 | WARN_ONCE(1, "Snapshot feature not enabled, but internal snapshot used"); | |
533 | } | |
1b22e382 | 534 | EXPORT_SYMBOL_GPL(tracing_snapshot); |
ad909e21 SRRH |
535 | void tracing_snapshot_alloc(void) |
536 | { | |
537 | /* Give warning */ | |
538 | tracing_snapshot(); | |
539 | } | |
1b22e382 | 540 | EXPORT_SYMBOL_GPL(tracing_snapshot_alloc); |
ad909e21 SRRH |
541 | #endif /* CONFIG_TRACER_SNAPSHOT */ |
542 | ||
499e5470 SR |
543 | /** |
544 | * tracing_off - turn off tracing buffers | |
545 | * | |
546 | * This function stops the tracing buffers from recording data. | |
547 | * It does not disable any overhead the tracers themselves may | |
548 | * be causing. This function simply causes all recording to | |
549 | * the ring buffers to fail. | |
550 | */ | |
551 | void tracing_off(void) | |
552 | { | |
12883efb SRRH |
553 | if (global_trace.trace_buffer.buffer) |
554 | ring_buffer_record_off(global_trace.trace_buffer.buffer); | |
499e5470 SR |
555 | /* |
556 | * This flag is only looked at when buffers haven't been | |
557 | * allocated yet. We don't really care about the race | |
558 | * between setting this flag and actually turning | |
559 | * on the buffer. | |
560 | */ | |
561 | global_trace.buffer_disabled = 1; | |
562 | } | |
563 | EXPORT_SYMBOL_GPL(tracing_off); | |
564 | ||
565 | /** | |
566 | * tracing_is_on - show state of ring buffers enabled | |
567 | */ | |
568 | int tracing_is_on(void) | |
569 | { | |
12883efb SRRH |
570 | if (global_trace.trace_buffer.buffer) |
571 | return ring_buffer_record_is_on(global_trace.trace_buffer.buffer); | |
499e5470 SR |
572 | return !global_trace.buffer_disabled; |
573 | } | |
574 | EXPORT_SYMBOL_GPL(tracing_is_on); | |
575 | ||
3928a8a2 | 576 | static int __init set_buf_size(char *str) |
bc0c38d1 | 577 | { |
3928a8a2 | 578 | unsigned long buf_size; |
c6caeeb1 | 579 | |
bc0c38d1 SR |
580 | if (!str) |
581 | return 0; | |
9d612bef | 582 | buf_size = memparse(str, &str); |
c6caeeb1 | 583 | /* nr_entries can not be zero */ |
9d612bef | 584 | if (buf_size == 0) |
c6caeeb1 | 585 | return 0; |
3928a8a2 | 586 | trace_buf_size = buf_size; |
bc0c38d1 SR |
587 | return 1; |
588 | } | |
3928a8a2 | 589 | __setup("trace_buf_size=", set_buf_size); |
bc0c38d1 | 590 | |
0e950173 TB |
591 | static int __init set_tracing_thresh(char *str) |
592 | { | |
87abb3b1 | 593 | unsigned long threshold; |
0e950173 TB |
594 | int ret; |
595 | ||
596 | if (!str) | |
597 | return 0; | |
bcd83ea6 | 598 | ret = kstrtoul(str, 0, &threshold); |
0e950173 TB |
599 | if (ret < 0) |
600 | return 0; | |
87abb3b1 | 601 | tracing_thresh = threshold * 1000; |
0e950173 TB |
602 | return 1; |
603 | } | |
604 | __setup("tracing_thresh=", set_tracing_thresh); | |
605 | ||
57f50be1 SR |
606 | unsigned long nsecs_to_usecs(unsigned long nsecs) |
607 | { | |
608 | return nsecs / 1000; | |
609 | } | |
610 | ||
4fcdae83 | 611 | /* These must match the bit postions in trace_iterator_flags */ |
bc0c38d1 SR |
612 | static const char *trace_options[] = { |
613 | "print-parent", | |
614 | "sym-offset", | |
615 | "sym-addr", | |
616 | "verbose", | |
f9896bf3 | 617 | "raw", |
5e3ca0ec | 618 | "hex", |
cb0f12aa | 619 | "bin", |
2a2cc8f7 | 620 | "block", |
86387f7e | 621 | "stacktrace", |
5e1607a0 | 622 | "trace_printk", |
b2a866f9 | 623 | "ftrace_preempt", |
9f029e83 | 624 | "branch", |
12ef7d44 | 625 | "annotate", |
02b67518 | 626 | "userstacktrace", |
b54d3de9 | 627 | "sym-userobj", |
66896a85 | 628 | "printk-msg-only", |
c4a8e8be | 629 | "context-info", |
c032ef64 | 630 | "latency-format", |
be6f164a | 631 | "sleep-time", |
a2a16d6a | 632 | "graph-time", |
e870e9a1 | 633 | "record-cmd", |
750912fa | 634 | "overwrite", |
cf30cf67 | 635 | "disable_on_free", |
77271ce4 | 636 | "irq-info", |
5224c3a3 | 637 | "markers", |
328df475 | 638 | "function-trace", |
bc0c38d1 SR |
639 | NULL |
640 | }; | |
641 | ||
5079f326 Z |
642 | static struct { |
643 | u64 (*func)(void); | |
644 | const char *name; | |
8be0709f | 645 | int in_ns; /* is this clock in nanoseconds? */ |
5079f326 | 646 | } trace_clocks[] = { |
8be0709f DS |
647 | { trace_clock_local, "local", 1 }, |
648 | { trace_clock_global, "global", 1 }, | |
649 | { trace_clock_counter, "counter", 0 }, | |
8aacf017 | 650 | { trace_clock_jiffies, "uptime", 1 }, |
76f11917 | 651 | { trace_clock, "perf", 1 }, |
8cbd9cc6 | 652 | ARCH_TRACE_CLOCKS |
5079f326 Z |
653 | }; |
654 | ||
655 | int trace_clock_id; | |
656 | ||
b63f39ea | 657 | /* |
658 | * trace_parser_get_init - gets the buffer for trace parser | |
659 | */ | |
660 | int trace_parser_get_init(struct trace_parser *parser, int size) | |
661 | { | |
662 | memset(parser, 0, sizeof(*parser)); | |
663 | ||
664 | parser->buffer = kmalloc(size, GFP_KERNEL); | |
665 | if (!parser->buffer) | |
666 | return 1; | |
667 | ||
668 | parser->size = size; | |
669 | return 0; | |
670 | } | |
671 | ||
672 | /* | |
673 | * trace_parser_put - frees the buffer for trace parser | |
674 | */ | |
675 | void trace_parser_put(struct trace_parser *parser) | |
676 | { | |
677 | kfree(parser->buffer); | |
678 | } | |
679 | ||
680 | /* | |
681 | * trace_get_user - reads the user input string separated by space | |
682 | * (matched by isspace(ch)) | |
683 | * | |
684 | * For each string found the 'struct trace_parser' is updated, | |
685 | * and the function returns. | |
686 | * | |
687 | * Returns number of bytes read. | |
688 | * | |
689 | * See kernel/trace/trace.h for 'struct trace_parser' details. | |
690 | */ | |
691 | int trace_get_user(struct trace_parser *parser, const char __user *ubuf, | |
692 | size_t cnt, loff_t *ppos) | |
693 | { | |
694 | char ch; | |
695 | size_t read = 0; | |
696 | ssize_t ret; | |
697 | ||
698 | if (!*ppos) | |
699 | trace_parser_clear(parser); | |
700 | ||
701 | ret = get_user(ch, ubuf++); | |
702 | if (ret) | |
703 | goto out; | |
704 | ||
705 | read++; | |
706 | cnt--; | |
707 | ||
708 | /* | |
709 | * The parser is not finished with the last write, | |
710 | * continue reading the user input without skipping spaces. | |
711 | */ | |
712 | if (!parser->cont) { | |
713 | /* skip white space */ | |
714 | while (cnt && isspace(ch)) { | |
715 | ret = get_user(ch, ubuf++); | |
716 | if (ret) | |
717 | goto out; | |
718 | read++; | |
719 | cnt--; | |
720 | } | |
721 | ||
722 | /* only spaces were written */ | |
723 | if (isspace(ch)) { | |
724 | *ppos += read; | |
725 | ret = read; | |
726 | goto out; | |
727 | } | |
728 | ||
729 | parser->idx = 0; | |
730 | } | |
731 | ||
732 | /* read the non-space input */ | |
733 | while (cnt && !isspace(ch)) { | |
3c235a33 | 734 | if (parser->idx < parser->size - 1) |
b63f39ea | 735 | parser->buffer[parser->idx++] = ch; |
736 | else { | |
737 | ret = -EINVAL; | |
738 | goto out; | |
739 | } | |
740 | ret = get_user(ch, ubuf++); | |
741 | if (ret) | |
742 | goto out; | |
743 | read++; | |
744 | cnt--; | |
745 | } | |
746 | ||
747 | /* We either got finished input or we have to wait for another call. */ | |
748 | if (isspace(ch)) { | |
749 | parser->buffer[parser->idx] = 0; | |
750 | parser->cont = false; | |
751 | } else { | |
752 | parser->cont = true; | |
753 | parser->buffer[parser->idx++] = ch; | |
754 | } | |
755 | ||
756 | *ppos += read; | |
757 | ret = read; | |
758 | ||
759 | out: | |
760 | return ret; | |
761 | } | |
762 | ||
6c6c2796 PP |
763 | ssize_t trace_seq_to_user(struct trace_seq *s, char __user *ubuf, size_t cnt) |
764 | { | |
765 | int len; | |
766 | int ret; | |
767 | ||
2dc5d12b SR |
768 | if (!cnt) |
769 | return 0; | |
770 | ||
6c6c2796 PP |
771 | if (s->len <= s->readpos) |
772 | return -EBUSY; | |
773 | ||
774 | len = s->len - s->readpos; | |
775 | if (cnt > len) | |
776 | cnt = len; | |
777 | ret = copy_to_user(ubuf, s->buffer + s->readpos, cnt); | |
2dc5d12b | 778 | if (ret == cnt) |
6c6c2796 PP |
779 | return -EFAULT; |
780 | ||
2dc5d12b SR |
781 | cnt -= ret; |
782 | ||
e74da523 | 783 | s->readpos += cnt; |
6c6c2796 | 784 | return cnt; |
214023c3 SR |
785 | } |
786 | ||
b8b94265 | 787 | static ssize_t trace_seq_to_buffer(struct trace_seq *s, void *buf, size_t cnt) |
3c56819b EGM |
788 | { |
789 | int len; | |
3c56819b EGM |
790 | |
791 | if (s->len <= s->readpos) | |
792 | return -EBUSY; | |
793 | ||
794 | len = s->len - s->readpos; | |
795 | if (cnt > len) | |
796 | cnt = len; | |
5a26c8f0 | 797 | memcpy(buf, s->buffer + s->readpos, cnt); |
3c56819b | 798 | |
e74da523 | 799 | s->readpos += cnt; |
3c56819b EGM |
800 | return cnt; |
801 | } | |
802 | ||
5d4a9dba SR |
803 | /* |
804 | * ftrace_max_lock is used to protect the swapping of buffers | |
805 | * when taking a max snapshot. The buffers themselves are | |
806 | * protected by per_cpu spinlocks. But the action of the swap | |
807 | * needs its own lock. | |
808 | * | |
445c8951 | 809 | * This is defined as a arch_spinlock_t in order to help |
5d4a9dba SR |
810 | * with performance when lockdep debugging is enabled. |
811 | * | |
812 | * It is also used in other places outside the update_max_tr | |
813 | * so it needs to be defined outside of the | |
814 | * CONFIG_TRACER_MAX_TRACE. | |
815 | */ | |
445c8951 | 816 | static arch_spinlock_t ftrace_max_lock = |
edc35bd7 | 817 | (arch_spinlock_t)__ARCH_SPIN_LOCK_UNLOCKED; |
5d4a9dba | 818 | |
0e950173 TB |
819 | unsigned long __read_mostly tracing_thresh; |
820 | ||
5d4a9dba SR |
821 | #ifdef CONFIG_TRACER_MAX_TRACE |
822 | unsigned long __read_mostly tracing_max_latency; | |
5d4a9dba SR |
823 | |
824 | /* | |
825 | * Copy the new maximum trace into the separate maximum-trace | |
826 | * structure. (this way the maximum trace is permanently saved, | |
827 | * for later retrieval via /sys/kernel/debug/tracing/latency_trace) | |
828 | */ | |
829 | static void | |
830 | __update_max_tr(struct trace_array *tr, struct task_struct *tsk, int cpu) | |
831 | { | |
12883efb SRRH |
832 | struct trace_buffer *trace_buf = &tr->trace_buffer; |
833 | struct trace_buffer *max_buf = &tr->max_buffer; | |
834 | struct trace_array_cpu *data = per_cpu_ptr(trace_buf->data, cpu); | |
835 | struct trace_array_cpu *max_data = per_cpu_ptr(max_buf->data, cpu); | |
5d4a9dba | 836 | |
12883efb SRRH |
837 | max_buf->cpu = cpu; |
838 | max_buf->time_start = data->preempt_timestamp; | |
5d4a9dba | 839 | |
8248ac05 SR |
840 | max_data->saved_latency = tracing_max_latency; |
841 | max_data->critical_start = data->critical_start; | |
842 | max_data->critical_end = data->critical_end; | |
5d4a9dba | 843 | |
1acaa1b2 | 844 | memcpy(max_data->comm, tsk->comm, TASK_COMM_LEN); |
8248ac05 | 845 | max_data->pid = tsk->pid; |
f17a5194 SRRH |
846 | /* |
847 | * If tsk == current, then use current_uid(), as that does not use | |
848 | * RCU. The irq tracer can be called out of RCU scope. | |
849 | */ | |
850 | if (tsk == current) | |
851 | max_data->uid = current_uid(); | |
852 | else | |
853 | max_data->uid = task_uid(tsk); | |
854 | ||
8248ac05 SR |
855 | max_data->nice = tsk->static_prio - 20 - MAX_RT_PRIO; |
856 | max_data->policy = tsk->policy; | |
857 | max_data->rt_priority = tsk->rt_priority; | |
5d4a9dba SR |
858 | |
859 | /* record this tasks comm */ | |
860 | tracing_record_cmdline(tsk); | |
861 | } | |
862 | ||
4fcdae83 SR |
863 | /** |
864 | * update_max_tr - snapshot all trace buffers from global_trace to max_tr | |
865 | * @tr: tracer | |
866 | * @tsk: the task with the latency | |
867 | * @cpu: The cpu that initiated the trace. | |
868 | * | |
869 | * Flip the buffers between the @tr and the max_tr and record information | |
870 | * about which task was the cause of this latency. | |
871 | */ | |
e309b41d | 872 | void |
bc0c38d1 SR |
873 | update_max_tr(struct trace_array *tr, struct task_struct *tsk, int cpu) |
874 | { | |
2721e72d | 875 | struct ring_buffer *buf; |
bc0c38d1 | 876 | |
2b6080f2 | 877 | if (tr->stop_count) |
b8de7bd1 SR |
878 | return; |
879 | ||
4c11d7ae | 880 | WARN_ON_ONCE(!irqs_disabled()); |
34600f0e | 881 | |
45ad21ca | 882 | if (!tr->allocated_snapshot) { |
debdd57f | 883 | /* Only the nop tracer should hit this when disabling */ |
2b6080f2 | 884 | WARN_ON_ONCE(tr->current_trace != &nop_trace); |
34600f0e | 885 | return; |
debdd57f | 886 | } |
34600f0e | 887 | |
0199c4e6 | 888 | arch_spin_lock(&ftrace_max_lock); |
3928a8a2 | 889 | |
12883efb SRRH |
890 | buf = tr->trace_buffer.buffer; |
891 | tr->trace_buffer.buffer = tr->max_buffer.buffer; | |
892 | tr->max_buffer.buffer = buf; | |
3928a8a2 | 893 | |
bc0c38d1 | 894 | __update_max_tr(tr, tsk, cpu); |
0199c4e6 | 895 | arch_spin_unlock(&ftrace_max_lock); |
bc0c38d1 SR |
896 | } |
897 | ||
898 | /** | |
899 | * update_max_tr_single - only copy one trace over, and reset the rest | |
900 | * @tr - tracer | |
901 | * @tsk - task with the latency | |
902 | * @cpu - the cpu of the buffer to copy. | |
4fcdae83 SR |
903 | * |
904 | * Flip the trace of a single CPU buffer between the @tr and the max_tr. | |
bc0c38d1 | 905 | */ |
e309b41d | 906 | void |
bc0c38d1 SR |
907 | update_max_tr_single(struct trace_array *tr, struct task_struct *tsk, int cpu) |
908 | { | |
3928a8a2 | 909 | int ret; |
bc0c38d1 | 910 | |
2b6080f2 | 911 | if (tr->stop_count) |
b8de7bd1 SR |
912 | return; |
913 | ||
4c11d7ae | 914 | WARN_ON_ONCE(!irqs_disabled()); |
6c24499f | 915 | if (!tr->allocated_snapshot) { |
2930e04d | 916 | /* Only the nop tracer should hit this when disabling */ |
9e8529af | 917 | WARN_ON_ONCE(tr->current_trace != &nop_trace); |
ef710e10 | 918 | return; |
2930e04d | 919 | } |
ef710e10 | 920 | |
0199c4e6 | 921 | arch_spin_lock(&ftrace_max_lock); |
bc0c38d1 | 922 | |
12883efb | 923 | ret = ring_buffer_swap_cpu(tr->max_buffer.buffer, tr->trace_buffer.buffer, cpu); |
3928a8a2 | 924 | |
e8165dbb SR |
925 | if (ret == -EBUSY) { |
926 | /* | |
927 | * We failed to swap the buffer due to a commit taking | |
928 | * place on this CPU. We fail to record, but we reset | |
929 | * the max trace buffer (no one writes directly to it) | |
930 | * and flag that it failed. | |
931 | */ | |
12883efb | 932 | trace_array_printk_buf(tr->max_buffer.buffer, _THIS_IP_, |
e8165dbb SR |
933 | "Failed to swap buffers due to commit in progress\n"); |
934 | } | |
935 | ||
e8165dbb | 936 | WARN_ON_ONCE(ret && ret != -EAGAIN && ret != -EBUSY); |
bc0c38d1 SR |
937 | |
938 | __update_max_tr(tr, tsk, cpu); | |
0199c4e6 | 939 | arch_spin_unlock(&ftrace_max_lock); |
bc0c38d1 | 940 | } |
5d4a9dba | 941 | #endif /* CONFIG_TRACER_MAX_TRACE */ |
bc0c38d1 | 942 | |
0d5c6e1c SR |
943 | static void default_wait_pipe(struct trace_iterator *iter) |
944 | { | |
15693458 SRRH |
945 | /* Iterators are static, they should be filled or empty */ |
946 | if (trace_buffer_iter(iter, iter->cpu_file)) | |
947 | return; | |
0d5c6e1c | 948 | |
12883efb | 949 | ring_buffer_wait(iter->trace_buffer->buffer, iter->cpu_file); |
0d5c6e1c SR |
950 | } |
951 | ||
f4e781c0 SRRH |
952 | #ifdef CONFIG_FTRACE_STARTUP_TEST |
953 | static int run_tracer_selftest(struct tracer *type) | |
954 | { | |
955 | struct trace_array *tr = &global_trace; | |
956 | struct tracer *saved_tracer = tr->current_trace; | |
957 | int ret; | |
0d5c6e1c | 958 | |
f4e781c0 SRRH |
959 | if (!type->selftest || tracing_selftest_disabled) |
960 | return 0; | |
0d5c6e1c SR |
961 | |
962 | /* | |
f4e781c0 SRRH |
963 | * Run a selftest on this tracer. |
964 | * Here we reset the trace buffer, and set the current | |
965 | * tracer to be this tracer. The tracer can then run some | |
966 | * internal tracing to verify that everything is in order. | |
967 | * If we fail, we do not register this tracer. | |
0d5c6e1c | 968 | */ |
f4e781c0 | 969 | tracing_reset_online_cpus(&tr->trace_buffer); |
0d5c6e1c | 970 | |
f4e781c0 SRRH |
971 | tr->current_trace = type; |
972 | ||
973 | #ifdef CONFIG_TRACER_MAX_TRACE | |
974 | if (type->use_max_tr) { | |
975 | /* If we expanded the buffers, make sure the max is expanded too */ | |
976 | if (ring_buffer_expanded) | |
977 | ring_buffer_resize(tr->max_buffer.buffer, trace_buf_size, | |
978 | RING_BUFFER_ALL_CPUS); | |
979 | tr->allocated_snapshot = true; | |
980 | } | |
981 | #endif | |
982 | ||
983 | /* the test is responsible for initializing and enabling */ | |
984 | pr_info("Testing tracer %s: ", type->name); | |
985 | ret = type->selftest(type, tr); | |
986 | /* the test is responsible for resetting too */ | |
987 | tr->current_trace = saved_tracer; | |
988 | if (ret) { | |
989 | printk(KERN_CONT "FAILED!\n"); | |
990 | /* Add the warning after printing 'FAILED' */ | |
991 | WARN_ON(1); | |
992 | return -1; | |
993 | } | |
994 | /* Only reset on passing, to avoid touching corrupted buffers */ | |
995 | tracing_reset_online_cpus(&tr->trace_buffer); | |
996 | ||
997 | #ifdef CONFIG_TRACER_MAX_TRACE | |
998 | if (type->use_max_tr) { | |
999 | tr->allocated_snapshot = false; | |
0d5c6e1c | 1000 | |
f4e781c0 SRRH |
1001 | /* Shrink the max buffer again */ |
1002 | if (ring_buffer_expanded) | |
1003 | ring_buffer_resize(tr->max_buffer.buffer, 1, | |
1004 | RING_BUFFER_ALL_CPUS); | |
1005 | } | |
1006 | #endif | |
1007 | ||
1008 | printk(KERN_CONT "PASSED\n"); | |
1009 | return 0; | |
1010 | } | |
1011 | #else | |
1012 | static inline int run_tracer_selftest(struct tracer *type) | |
1013 | { | |
1014 | return 0; | |
0d5c6e1c | 1015 | } |
f4e781c0 | 1016 | #endif /* CONFIG_FTRACE_STARTUP_TEST */ |
0d5c6e1c | 1017 | |
4fcdae83 SR |
1018 | /** |
1019 | * register_tracer - register a tracer with the ftrace system. | |
1020 | * @type - the plugin for the tracer | |
1021 | * | |
1022 | * Register a new plugin tracer. | |
1023 | */ | |
bc0c38d1 SR |
1024 | int register_tracer(struct tracer *type) |
1025 | { | |
1026 | struct tracer *t; | |
bc0c38d1 SR |
1027 | int ret = 0; |
1028 | ||
1029 | if (!type->name) { | |
1030 | pr_info("Tracer must have a name\n"); | |
1031 | return -1; | |
1032 | } | |
1033 | ||
24a461d5 | 1034 | if (strlen(type->name) >= MAX_TRACER_SIZE) { |
ee6c2c1b LZ |
1035 | pr_info("Tracer has a name longer than %d\n", MAX_TRACER_SIZE); |
1036 | return -1; | |
1037 | } | |
1038 | ||
bc0c38d1 | 1039 | mutex_lock(&trace_types_lock); |
86fa2f60 | 1040 | |
8e1b82e0 FW |
1041 | tracing_selftest_running = true; |
1042 | ||
bc0c38d1 SR |
1043 | for (t = trace_types; t; t = t->next) { |
1044 | if (strcmp(type->name, t->name) == 0) { | |
1045 | /* already found */ | |
ee6c2c1b | 1046 | pr_info("Tracer %s already registered\n", |
bc0c38d1 SR |
1047 | type->name); |
1048 | ret = -1; | |
1049 | goto out; | |
1050 | } | |
1051 | } | |
1052 | ||
adf9f195 FW |
1053 | if (!type->set_flag) |
1054 | type->set_flag = &dummy_set_flag; | |
1055 | if (!type->flags) | |
1056 | type->flags = &dummy_tracer_flags; | |
1057 | else | |
1058 | if (!type->flags->opts) | |
1059 | type->flags->opts = dummy_tracer_opt; | |
6eaaa5d5 FW |
1060 | if (!type->wait_pipe) |
1061 | type->wait_pipe = default_wait_pipe; | |
1062 | ||
f4e781c0 SRRH |
1063 | ret = run_tracer_selftest(type); |
1064 | if (ret < 0) | |
1065 | goto out; | |
60a11774 | 1066 | |
bc0c38d1 SR |
1067 | type->next = trace_types; |
1068 | trace_types = type; | |
60a11774 | 1069 | |
bc0c38d1 | 1070 | out: |
8e1b82e0 | 1071 | tracing_selftest_running = false; |
bc0c38d1 SR |
1072 | mutex_unlock(&trace_types_lock); |
1073 | ||
dac74940 SR |
1074 | if (ret || !default_bootup_tracer) |
1075 | goto out_unlock; | |
1076 | ||
ee6c2c1b | 1077 | if (strncmp(default_bootup_tracer, type->name, MAX_TRACER_SIZE)) |
dac74940 SR |
1078 | goto out_unlock; |
1079 | ||
1080 | printk(KERN_INFO "Starting tracer '%s'\n", type->name); | |
1081 | /* Do we want this tracer to start on bootup? */ | |
1082 | tracing_set_tracer(type->name); | |
1083 | default_bootup_tracer = NULL; | |
1084 | /* disable other selftests, since this will break it. */ | |
55034cd6 | 1085 | tracing_selftest_disabled = true; |
b2821ae6 | 1086 | #ifdef CONFIG_FTRACE_STARTUP_TEST |
dac74940 SR |
1087 | printk(KERN_INFO "Disabling FTRACE selftests due to running tracer '%s'\n", |
1088 | type->name); | |
b2821ae6 | 1089 | #endif |
b2821ae6 | 1090 | |
dac74940 | 1091 | out_unlock: |
bc0c38d1 SR |
1092 | return ret; |
1093 | } | |
1094 | ||
12883efb | 1095 | void tracing_reset(struct trace_buffer *buf, int cpu) |
f633903a | 1096 | { |
12883efb | 1097 | struct ring_buffer *buffer = buf->buffer; |
f633903a | 1098 | |
a5416411 HT |
1099 | if (!buffer) |
1100 | return; | |
1101 | ||
f633903a SR |
1102 | ring_buffer_record_disable(buffer); |
1103 | ||
1104 | /* Make sure all commits have finished */ | |
1105 | synchronize_sched(); | |
68179686 | 1106 | ring_buffer_reset_cpu(buffer, cpu); |
f633903a SR |
1107 | |
1108 | ring_buffer_record_enable(buffer); | |
1109 | } | |
1110 | ||
12883efb | 1111 | void tracing_reset_online_cpus(struct trace_buffer *buf) |
213cc060 | 1112 | { |
12883efb | 1113 | struct ring_buffer *buffer = buf->buffer; |
213cc060 PE |
1114 | int cpu; |
1115 | ||
a5416411 HT |
1116 | if (!buffer) |
1117 | return; | |
1118 | ||
621968cd SR |
1119 | ring_buffer_record_disable(buffer); |
1120 | ||
1121 | /* Make sure all commits have finished */ | |
1122 | synchronize_sched(); | |
1123 | ||
12883efb | 1124 | buf->time_start = ftrace_now(buf->cpu); |
213cc060 PE |
1125 | |
1126 | for_each_online_cpu(cpu) | |
68179686 | 1127 | ring_buffer_reset_cpu(buffer, cpu); |
621968cd SR |
1128 | |
1129 | ring_buffer_record_enable(buffer); | |
213cc060 PE |
1130 | } |
1131 | ||
9456f0fa SR |
1132 | void tracing_reset_current(int cpu) |
1133 | { | |
12883efb | 1134 | tracing_reset(&global_trace.trace_buffer, cpu); |
9456f0fa SR |
1135 | } |
1136 | ||
873c642f | 1137 | void tracing_reset_all_online_cpus(void) |
9456f0fa | 1138 | { |
873c642f SRRH |
1139 | struct trace_array *tr; |
1140 | ||
1141 | mutex_lock(&trace_types_lock); | |
1142 | list_for_each_entry(tr, &ftrace_trace_arrays, list) { | |
12883efb SRRH |
1143 | tracing_reset_online_cpus(&tr->trace_buffer); |
1144 | #ifdef CONFIG_TRACER_MAX_TRACE | |
1145 | tracing_reset_online_cpus(&tr->max_buffer); | |
1146 | #endif | |
873c642f SRRH |
1147 | } |
1148 | mutex_unlock(&trace_types_lock); | |
9456f0fa SR |
1149 | } |
1150 | ||
bc0c38d1 | 1151 | #define SAVED_CMDLINES 128 |
2c7eea4c | 1152 | #define NO_CMDLINE_MAP UINT_MAX |
bc0c38d1 SR |
1153 | static unsigned map_pid_to_cmdline[PID_MAX_DEFAULT+1]; |
1154 | static unsigned map_cmdline_to_pid[SAVED_CMDLINES]; | |
1155 | static char saved_cmdlines[SAVED_CMDLINES][TASK_COMM_LEN]; | |
1156 | static int cmdline_idx; | |
edc35bd7 | 1157 | static arch_spinlock_t trace_cmdline_lock = __ARCH_SPIN_LOCK_UNLOCKED; |
25b0b44a | 1158 | |
25b0b44a | 1159 | /* temporary disable recording */ |
4fd27358 | 1160 | static atomic_t trace_record_cmdline_disabled __read_mostly; |
bc0c38d1 SR |
1161 | |
1162 | static void trace_init_cmdlines(void) | |
1163 | { | |
2c7eea4c TG |
1164 | memset(&map_pid_to_cmdline, NO_CMDLINE_MAP, sizeof(map_pid_to_cmdline)); |
1165 | memset(&map_cmdline_to_pid, NO_CMDLINE_MAP, sizeof(map_cmdline_to_pid)); | |
bc0c38d1 SR |
1166 | cmdline_idx = 0; |
1167 | } | |
1168 | ||
b5130b1e CE |
1169 | int is_tracing_stopped(void) |
1170 | { | |
2b6080f2 | 1171 | return global_trace.stop_count; |
b5130b1e CE |
1172 | } |
1173 | ||
69bb54ec SR |
1174 | /** |
1175 | * ftrace_off_permanent - disable all ftrace code permanently | |
1176 | * | |
1177 | * This should only be called when a serious anomally has | |
1178 | * been detected. This will turn off the function tracing, | |
1179 | * ring buffers, and other tracing utilites. It takes no | |
1180 | * locks and can be called from any context. | |
1181 | */ | |
1182 | void ftrace_off_permanent(void) | |
1183 | { | |
1184 | tracing_disabled = 1; | |
1185 | ftrace_stop(); | |
1186 | tracing_off_permanent(); | |
1187 | } | |
1188 | ||
0f048701 SR |
1189 | /** |
1190 | * tracing_start - quick start of the tracer | |
1191 | * | |
1192 | * If tracing is enabled but was stopped by tracing_stop, | |
1193 | * this will start the tracer back up. | |
1194 | */ | |
1195 | void tracing_start(void) | |
1196 | { | |
1197 | struct ring_buffer *buffer; | |
1198 | unsigned long flags; | |
1199 | ||
1200 | if (tracing_disabled) | |
1201 | return; | |
1202 | ||
2b6080f2 SR |
1203 | raw_spin_lock_irqsave(&global_trace.start_lock, flags); |
1204 | if (--global_trace.stop_count) { | |
1205 | if (global_trace.stop_count < 0) { | |
b06a8301 SR |
1206 | /* Someone screwed up their debugging */ |
1207 | WARN_ON_ONCE(1); | |
2b6080f2 | 1208 | global_trace.stop_count = 0; |
b06a8301 | 1209 | } |
0f048701 SR |
1210 | goto out; |
1211 | } | |
1212 | ||
a2f80714 SR |
1213 | /* Prevent the buffers from switching */ |
1214 | arch_spin_lock(&ftrace_max_lock); | |
0f048701 | 1215 | |
12883efb | 1216 | buffer = global_trace.trace_buffer.buffer; |
0f048701 SR |
1217 | if (buffer) |
1218 | ring_buffer_record_enable(buffer); | |
1219 | ||
12883efb SRRH |
1220 | #ifdef CONFIG_TRACER_MAX_TRACE |
1221 | buffer = global_trace.max_buffer.buffer; | |
0f048701 SR |
1222 | if (buffer) |
1223 | ring_buffer_record_enable(buffer); | |
12883efb | 1224 | #endif |
0f048701 | 1225 | |
a2f80714 SR |
1226 | arch_spin_unlock(&ftrace_max_lock); |
1227 | ||
0f048701 SR |
1228 | ftrace_start(); |
1229 | out: | |
2b6080f2 SR |
1230 | raw_spin_unlock_irqrestore(&global_trace.start_lock, flags); |
1231 | } | |
1232 | ||
1233 | static void tracing_start_tr(struct trace_array *tr) | |
1234 | { | |
1235 | struct ring_buffer *buffer; | |
1236 | unsigned long flags; | |
1237 | ||
1238 | if (tracing_disabled) | |
1239 | return; | |
1240 | ||
1241 | /* If global, we need to also start the max tracer */ | |
1242 | if (tr->flags & TRACE_ARRAY_FL_GLOBAL) | |
1243 | return tracing_start(); | |
1244 | ||
1245 | raw_spin_lock_irqsave(&tr->start_lock, flags); | |
1246 | ||
1247 | if (--tr->stop_count) { | |
1248 | if (tr->stop_count < 0) { | |
1249 | /* Someone screwed up their debugging */ | |
1250 | WARN_ON_ONCE(1); | |
1251 | tr->stop_count = 0; | |
1252 | } | |
1253 | goto out; | |
1254 | } | |
1255 | ||
12883efb | 1256 | buffer = tr->trace_buffer.buffer; |
2b6080f2 SR |
1257 | if (buffer) |
1258 | ring_buffer_record_enable(buffer); | |
1259 | ||
1260 | out: | |
1261 | raw_spin_unlock_irqrestore(&tr->start_lock, flags); | |
0f048701 SR |
1262 | } |
1263 | ||
1264 | /** | |
1265 | * tracing_stop - quick stop of the tracer | |
1266 | * | |
1267 | * Light weight way to stop tracing. Use in conjunction with | |
1268 | * tracing_start. | |
1269 | */ | |
1270 | void tracing_stop(void) | |
1271 | { | |
1272 | struct ring_buffer *buffer; | |
1273 | unsigned long flags; | |
1274 | ||
1275 | ftrace_stop(); | |
2b6080f2 SR |
1276 | raw_spin_lock_irqsave(&global_trace.start_lock, flags); |
1277 | if (global_trace.stop_count++) | |
0f048701 SR |
1278 | goto out; |
1279 | ||
a2f80714 SR |
1280 | /* Prevent the buffers from switching */ |
1281 | arch_spin_lock(&ftrace_max_lock); | |
1282 | ||
12883efb | 1283 | buffer = global_trace.trace_buffer.buffer; |
0f048701 SR |
1284 | if (buffer) |
1285 | ring_buffer_record_disable(buffer); | |
1286 | ||
12883efb SRRH |
1287 | #ifdef CONFIG_TRACER_MAX_TRACE |
1288 | buffer = global_trace.max_buffer.buffer; | |
0f048701 SR |
1289 | if (buffer) |
1290 | ring_buffer_record_disable(buffer); | |
12883efb | 1291 | #endif |
0f048701 | 1292 | |
a2f80714 SR |
1293 | arch_spin_unlock(&ftrace_max_lock); |
1294 | ||
0f048701 | 1295 | out: |
2b6080f2 SR |
1296 | raw_spin_unlock_irqrestore(&global_trace.start_lock, flags); |
1297 | } | |
1298 | ||
1299 | static void tracing_stop_tr(struct trace_array *tr) | |
1300 | { | |
1301 | struct ring_buffer *buffer; | |
1302 | unsigned long flags; | |
1303 | ||
1304 | /* If global, we need to also stop the max tracer */ | |
1305 | if (tr->flags & TRACE_ARRAY_FL_GLOBAL) | |
1306 | return tracing_stop(); | |
1307 | ||
1308 | raw_spin_lock_irqsave(&tr->start_lock, flags); | |
1309 | if (tr->stop_count++) | |
1310 | goto out; | |
1311 | ||
12883efb | 1312 | buffer = tr->trace_buffer.buffer; |
2b6080f2 SR |
1313 | if (buffer) |
1314 | ring_buffer_record_disable(buffer); | |
1315 | ||
1316 | out: | |
1317 | raw_spin_unlock_irqrestore(&tr->start_lock, flags); | |
0f048701 SR |
1318 | } |
1319 | ||
e309b41d | 1320 | void trace_stop_cmdline_recording(void); |
bc0c38d1 | 1321 | |
e309b41d | 1322 | static void trace_save_cmdline(struct task_struct *tsk) |
bc0c38d1 | 1323 | { |
a635cf04 | 1324 | unsigned pid, idx; |
bc0c38d1 SR |
1325 | |
1326 | if (!tsk->pid || unlikely(tsk->pid > PID_MAX_DEFAULT)) | |
1327 | return; | |
1328 | ||
1329 | /* | |
1330 | * It's not the end of the world if we don't get | |
1331 | * the lock, but we also don't want to spin | |
1332 | * nor do we want to disable interrupts, | |
1333 | * so if we miss here, then better luck next time. | |
1334 | */ | |
0199c4e6 | 1335 | if (!arch_spin_trylock(&trace_cmdline_lock)) |
bc0c38d1 SR |
1336 | return; |
1337 | ||
1338 | idx = map_pid_to_cmdline[tsk->pid]; | |
2c7eea4c | 1339 | if (idx == NO_CMDLINE_MAP) { |
bc0c38d1 SR |
1340 | idx = (cmdline_idx + 1) % SAVED_CMDLINES; |
1341 | ||
a635cf04 CE |
1342 | /* |
1343 | * Check whether the cmdline buffer at idx has a pid | |
1344 | * mapped. We are going to overwrite that entry so we | |
1345 | * need to clear the map_pid_to_cmdline. Otherwise we | |
1346 | * would read the new comm for the old pid. | |
1347 | */ | |
1348 | pid = map_cmdline_to_pid[idx]; | |
1349 | if (pid != NO_CMDLINE_MAP) | |
1350 | map_pid_to_cmdline[pid] = NO_CMDLINE_MAP; | |
bc0c38d1 | 1351 | |
a635cf04 | 1352 | map_cmdline_to_pid[idx] = tsk->pid; |
bc0c38d1 SR |
1353 | map_pid_to_cmdline[tsk->pid] = idx; |
1354 | ||
1355 | cmdline_idx = idx; | |
1356 | } | |
1357 | ||
1358 | memcpy(&saved_cmdlines[idx], tsk->comm, TASK_COMM_LEN); | |
1359 | ||
0199c4e6 | 1360 | arch_spin_unlock(&trace_cmdline_lock); |
bc0c38d1 SR |
1361 | } |
1362 | ||
4ca53085 | 1363 | void trace_find_cmdline(int pid, char comm[]) |
bc0c38d1 | 1364 | { |
bc0c38d1 SR |
1365 | unsigned map; |
1366 | ||
4ca53085 SR |
1367 | if (!pid) { |
1368 | strcpy(comm, "<idle>"); | |
1369 | return; | |
1370 | } | |
bc0c38d1 | 1371 | |
74bf4076 SR |
1372 | if (WARN_ON_ONCE(pid < 0)) { |
1373 | strcpy(comm, "<XXX>"); | |
1374 | return; | |
1375 | } | |
1376 | ||
4ca53085 SR |
1377 | if (pid > PID_MAX_DEFAULT) { |
1378 | strcpy(comm, "<...>"); | |
1379 | return; | |
1380 | } | |
bc0c38d1 | 1381 | |
5b6045a9 | 1382 | preempt_disable(); |
0199c4e6 | 1383 | arch_spin_lock(&trace_cmdline_lock); |
bc0c38d1 | 1384 | map = map_pid_to_cmdline[pid]; |
50d88758 TG |
1385 | if (map != NO_CMDLINE_MAP) |
1386 | strcpy(comm, saved_cmdlines[map]); | |
1387 | else | |
1388 | strcpy(comm, "<...>"); | |
bc0c38d1 | 1389 | |
0199c4e6 | 1390 | arch_spin_unlock(&trace_cmdline_lock); |
5b6045a9 | 1391 | preempt_enable(); |
bc0c38d1 SR |
1392 | } |
1393 | ||
e309b41d | 1394 | void tracing_record_cmdline(struct task_struct *tsk) |
bc0c38d1 | 1395 | { |
0fb9656d | 1396 | if (atomic_read(&trace_record_cmdline_disabled) || !tracing_is_on()) |
bc0c38d1 SR |
1397 | return; |
1398 | ||
7ffbd48d SR |
1399 | if (!__this_cpu_read(trace_cmdline_save)) |
1400 | return; | |
1401 | ||
1402 | __this_cpu_write(trace_cmdline_save, false); | |
1403 | ||
bc0c38d1 SR |
1404 | trace_save_cmdline(tsk); |
1405 | } | |
1406 | ||
45dcd8b8 | 1407 | void |
38697053 SR |
1408 | tracing_generic_entry_update(struct trace_entry *entry, unsigned long flags, |
1409 | int pc) | |
bc0c38d1 SR |
1410 | { |
1411 | struct task_struct *tsk = current; | |
bc0c38d1 | 1412 | |
777e208d SR |
1413 | entry->preempt_count = pc & 0xff; |
1414 | entry->pid = (tsk) ? tsk->pid : 0; | |
1415 | entry->flags = | |
9244489a | 1416 | #ifdef CONFIG_TRACE_IRQFLAGS_SUPPORT |
2e2ca155 | 1417 | (irqs_disabled_flags(flags) ? TRACE_FLAG_IRQS_OFF : 0) | |
9244489a SR |
1418 | #else |
1419 | TRACE_FLAG_IRQS_NOSUPPORT | | |
1420 | #endif | |
bc0c38d1 SR |
1421 | ((pc & HARDIRQ_MASK) ? TRACE_FLAG_HARDIRQ : 0) | |
1422 | ((pc & SOFTIRQ_MASK) ? TRACE_FLAG_SOFTIRQ : 0) | | |
1423 | (need_resched() ? TRACE_FLAG_NEED_RESCHED : 0); | |
1424 | } | |
f413cdb8 | 1425 | EXPORT_SYMBOL_GPL(tracing_generic_entry_update); |
bc0c38d1 | 1426 | |
e77405ad SR |
1427 | struct ring_buffer_event * |
1428 | trace_buffer_lock_reserve(struct ring_buffer *buffer, | |
1429 | int type, | |
1430 | unsigned long len, | |
1431 | unsigned long flags, int pc) | |
51a763dd ACM |
1432 | { |
1433 | struct ring_buffer_event *event; | |
1434 | ||
e77405ad | 1435 | event = ring_buffer_lock_reserve(buffer, len); |
51a763dd ACM |
1436 | if (event != NULL) { |
1437 | struct trace_entry *ent = ring_buffer_event_data(event); | |
1438 | ||
1439 | tracing_generic_entry_update(ent, flags, pc); | |
1440 | ent->type = type; | |
1441 | } | |
1442 | ||
1443 | return event; | |
1444 | } | |
51a763dd | 1445 | |
7ffbd48d SR |
1446 | void |
1447 | __buffer_unlock_commit(struct ring_buffer *buffer, struct ring_buffer_event *event) | |
1448 | { | |
1449 | __this_cpu_write(trace_cmdline_save, true); | |
1450 | ring_buffer_unlock_commit(buffer, event); | |
1451 | } | |
1452 | ||
e77405ad SR |
1453 | static inline void |
1454 | __trace_buffer_unlock_commit(struct ring_buffer *buffer, | |
1455 | struct ring_buffer_event *event, | |
0d5c6e1c | 1456 | unsigned long flags, int pc) |
51a763dd | 1457 | { |
7ffbd48d | 1458 | __buffer_unlock_commit(buffer, event); |
51a763dd | 1459 | |
e77405ad SR |
1460 | ftrace_trace_stack(buffer, flags, 6, pc); |
1461 | ftrace_trace_userstack(buffer, flags, pc); | |
07edf712 FW |
1462 | } |
1463 | ||
e77405ad SR |
1464 | void trace_buffer_unlock_commit(struct ring_buffer *buffer, |
1465 | struct ring_buffer_event *event, | |
1466 | unsigned long flags, int pc) | |
07edf712 | 1467 | { |
0d5c6e1c | 1468 | __trace_buffer_unlock_commit(buffer, event, flags, pc); |
51a763dd | 1469 | } |
0d5c6e1c | 1470 | EXPORT_SYMBOL_GPL(trace_buffer_unlock_commit); |
51a763dd | 1471 | |
ccb469a1 SR |
1472 | struct ring_buffer_event * |
1473 | trace_event_buffer_lock_reserve(struct ring_buffer **current_rb, | |
1474 | struct ftrace_event_file *ftrace_file, | |
1475 | int type, unsigned long len, | |
1476 | unsigned long flags, int pc) | |
1477 | { | |
12883efb | 1478 | *current_rb = ftrace_file->tr->trace_buffer.buffer; |
ccb469a1 SR |
1479 | return trace_buffer_lock_reserve(*current_rb, |
1480 | type, len, flags, pc); | |
1481 | } | |
1482 | EXPORT_SYMBOL_GPL(trace_event_buffer_lock_reserve); | |
1483 | ||
ef5580d0 | 1484 | struct ring_buffer_event * |
e77405ad SR |
1485 | trace_current_buffer_lock_reserve(struct ring_buffer **current_rb, |
1486 | int type, unsigned long len, | |
ef5580d0 SR |
1487 | unsigned long flags, int pc) |
1488 | { | |
12883efb | 1489 | *current_rb = global_trace.trace_buffer.buffer; |
e77405ad | 1490 | return trace_buffer_lock_reserve(*current_rb, |
ef5580d0 SR |
1491 | type, len, flags, pc); |
1492 | } | |
94487d6d | 1493 | EXPORT_SYMBOL_GPL(trace_current_buffer_lock_reserve); |
ef5580d0 | 1494 | |
e77405ad SR |
1495 | void trace_current_buffer_unlock_commit(struct ring_buffer *buffer, |
1496 | struct ring_buffer_event *event, | |
ef5580d0 SR |
1497 | unsigned long flags, int pc) |
1498 | { | |
0d5c6e1c | 1499 | __trace_buffer_unlock_commit(buffer, event, flags, pc); |
07edf712 | 1500 | } |
94487d6d | 1501 | EXPORT_SYMBOL_GPL(trace_current_buffer_unlock_commit); |
07edf712 | 1502 | |
0d5c6e1c SR |
1503 | void trace_buffer_unlock_commit_regs(struct ring_buffer *buffer, |
1504 | struct ring_buffer_event *event, | |
1505 | unsigned long flags, int pc, | |
1506 | struct pt_regs *regs) | |
1fd8df2c | 1507 | { |
7ffbd48d | 1508 | __buffer_unlock_commit(buffer, event); |
1fd8df2c MH |
1509 | |
1510 | ftrace_trace_stack_regs(buffer, flags, 0, pc, regs); | |
1511 | ftrace_trace_userstack(buffer, flags, pc); | |
1512 | } | |
0d5c6e1c | 1513 | EXPORT_SYMBOL_GPL(trace_buffer_unlock_commit_regs); |
1fd8df2c | 1514 | |
e77405ad SR |
1515 | void trace_current_buffer_discard_commit(struct ring_buffer *buffer, |
1516 | struct ring_buffer_event *event) | |
77d9f465 | 1517 | { |
e77405ad | 1518 | ring_buffer_discard_commit(buffer, event); |
ef5580d0 | 1519 | } |
12acd473 | 1520 | EXPORT_SYMBOL_GPL(trace_current_buffer_discard_commit); |
ef5580d0 | 1521 | |
e309b41d | 1522 | void |
7be42151 | 1523 | trace_function(struct trace_array *tr, |
38697053 SR |
1524 | unsigned long ip, unsigned long parent_ip, unsigned long flags, |
1525 | int pc) | |
bc0c38d1 | 1526 | { |
e1112b4d | 1527 | struct ftrace_event_call *call = &event_function; |
12883efb | 1528 | struct ring_buffer *buffer = tr->trace_buffer.buffer; |
3928a8a2 | 1529 | struct ring_buffer_event *event; |
777e208d | 1530 | struct ftrace_entry *entry; |
bc0c38d1 | 1531 | |
d769041f | 1532 | /* If we are reading the ring buffer, don't trace */ |
dd17c8f7 | 1533 | if (unlikely(__this_cpu_read(ftrace_cpu_disabled))) |
d769041f SR |
1534 | return; |
1535 | ||
e77405ad | 1536 | event = trace_buffer_lock_reserve(buffer, TRACE_FN, sizeof(*entry), |
51a763dd | 1537 | flags, pc); |
3928a8a2 SR |
1538 | if (!event) |
1539 | return; | |
1540 | entry = ring_buffer_event_data(event); | |
777e208d SR |
1541 | entry->ip = ip; |
1542 | entry->parent_ip = parent_ip; | |
e1112b4d | 1543 | |
e77405ad | 1544 | if (!filter_check_discard(call, entry, buffer, event)) |
7ffbd48d | 1545 | __buffer_unlock_commit(buffer, event); |
bc0c38d1 SR |
1546 | } |
1547 | ||
e309b41d | 1548 | void |
2e0f5761 | 1549 | ftrace(struct trace_array *tr, struct trace_array_cpu *data, |
38697053 SR |
1550 | unsigned long ip, unsigned long parent_ip, unsigned long flags, |
1551 | int pc) | |
2e0f5761 IM |
1552 | { |
1553 | if (likely(!atomic_read(&data->disabled))) | |
7be42151 | 1554 | trace_function(tr, ip, parent_ip, flags, pc); |
2e0f5761 IM |
1555 | } |
1556 | ||
c0a0d0d3 | 1557 | #ifdef CONFIG_STACKTRACE |
4a9bd3f1 SR |
1558 | |
1559 | #define FTRACE_STACK_MAX_ENTRIES (PAGE_SIZE / sizeof(unsigned long)) | |
1560 | struct ftrace_stack { | |
1561 | unsigned long calls[FTRACE_STACK_MAX_ENTRIES]; | |
1562 | }; | |
1563 | ||
1564 | static DEFINE_PER_CPU(struct ftrace_stack, ftrace_stack); | |
1565 | static DEFINE_PER_CPU(int, ftrace_stack_reserve); | |
1566 | ||
e77405ad | 1567 | static void __ftrace_trace_stack(struct ring_buffer *buffer, |
53614991 | 1568 | unsigned long flags, |
1fd8df2c | 1569 | int skip, int pc, struct pt_regs *regs) |
86387f7e | 1570 | { |
e1112b4d | 1571 | struct ftrace_event_call *call = &event_kernel_stack; |
3928a8a2 | 1572 | struct ring_buffer_event *event; |
777e208d | 1573 | struct stack_entry *entry; |
86387f7e | 1574 | struct stack_trace trace; |
4a9bd3f1 SR |
1575 | int use_stack; |
1576 | int size = FTRACE_STACK_ENTRIES; | |
1577 | ||
1578 | trace.nr_entries = 0; | |
1579 | trace.skip = skip; | |
1580 | ||
1581 | /* | |
1582 | * Since events can happen in NMIs there's no safe way to | |
1583 | * use the per cpu ftrace_stacks. We reserve it and if an interrupt | |
1584 | * or NMI comes in, it will just have to use the default | |
1585 | * FTRACE_STACK_SIZE. | |
1586 | */ | |
1587 | preempt_disable_notrace(); | |
1588 | ||
82146529 | 1589 | use_stack = __this_cpu_inc_return(ftrace_stack_reserve); |
4a9bd3f1 SR |
1590 | /* |
1591 | * We don't need any atomic variables, just a barrier. | |
1592 | * If an interrupt comes in, we don't care, because it would | |
1593 | * have exited and put the counter back to what we want. | |
1594 | * We just need a barrier to keep gcc from moving things | |
1595 | * around. | |
1596 | */ | |
1597 | barrier(); | |
1598 | if (use_stack == 1) { | |
1599 | trace.entries = &__get_cpu_var(ftrace_stack).calls[0]; | |
1600 | trace.max_entries = FTRACE_STACK_MAX_ENTRIES; | |
1601 | ||
1602 | if (regs) | |
1603 | save_stack_trace_regs(regs, &trace); | |
1604 | else | |
1605 | save_stack_trace(&trace); | |
1606 | ||
1607 | if (trace.nr_entries > size) | |
1608 | size = trace.nr_entries; | |
1609 | } else | |
1610 | /* From now on, use_stack is a boolean */ | |
1611 | use_stack = 0; | |
1612 | ||
1613 | size *= sizeof(unsigned long); | |
86387f7e | 1614 | |
e77405ad | 1615 | event = trace_buffer_lock_reserve(buffer, TRACE_STACK, |
4a9bd3f1 | 1616 | sizeof(*entry) + size, flags, pc); |
3928a8a2 | 1617 | if (!event) |
4a9bd3f1 SR |
1618 | goto out; |
1619 | entry = ring_buffer_event_data(event); | |
86387f7e | 1620 | |
4a9bd3f1 SR |
1621 | memset(&entry->caller, 0, size); |
1622 | ||
1623 | if (use_stack) | |
1624 | memcpy(&entry->caller, trace.entries, | |
1625 | trace.nr_entries * sizeof(unsigned long)); | |
1626 | else { | |
1627 | trace.max_entries = FTRACE_STACK_ENTRIES; | |
1628 | trace.entries = entry->caller; | |
1629 | if (regs) | |
1630 | save_stack_trace_regs(regs, &trace); | |
1631 | else | |
1632 | save_stack_trace(&trace); | |
1633 | } | |
1634 | ||
1635 | entry->size = trace.nr_entries; | |
86387f7e | 1636 | |
e77405ad | 1637 | if (!filter_check_discard(call, entry, buffer, event)) |
7ffbd48d | 1638 | __buffer_unlock_commit(buffer, event); |
4a9bd3f1 SR |
1639 | |
1640 | out: | |
1641 | /* Again, don't let gcc optimize things here */ | |
1642 | barrier(); | |
82146529 | 1643 | __this_cpu_dec(ftrace_stack_reserve); |
4a9bd3f1 SR |
1644 | preempt_enable_notrace(); |
1645 | ||
f0a920d5 IM |
1646 | } |
1647 | ||
1fd8df2c MH |
1648 | void ftrace_trace_stack_regs(struct ring_buffer *buffer, unsigned long flags, |
1649 | int skip, int pc, struct pt_regs *regs) | |
1650 | { | |
1651 | if (!(trace_flags & TRACE_ITER_STACKTRACE)) | |
1652 | return; | |
1653 | ||
1654 | __ftrace_trace_stack(buffer, flags, skip, pc, regs); | |
1655 | } | |
1656 | ||
e77405ad SR |
1657 | void ftrace_trace_stack(struct ring_buffer *buffer, unsigned long flags, |
1658 | int skip, int pc) | |
53614991 SR |
1659 | { |
1660 | if (!(trace_flags & TRACE_ITER_STACKTRACE)) | |
1661 | return; | |
1662 | ||
1fd8df2c | 1663 | __ftrace_trace_stack(buffer, flags, skip, pc, NULL); |
53614991 SR |
1664 | } |
1665 | ||
c0a0d0d3 FW |
1666 | void __trace_stack(struct trace_array *tr, unsigned long flags, int skip, |
1667 | int pc) | |
38697053 | 1668 | { |
12883efb | 1669 | __ftrace_trace_stack(tr->trace_buffer.buffer, flags, skip, pc, NULL); |
38697053 SR |
1670 | } |
1671 | ||
03889384 SR |
1672 | /** |
1673 | * trace_dump_stack - record a stack back trace in the trace buffer | |
c142be8e | 1674 | * @skip: Number of functions to skip (helper handlers) |
03889384 | 1675 | */ |
c142be8e | 1676 | void trace_dump_stack(int skip) |
03889384 SR |
1677 | { |
1678 | unsigned long flags; | |
1679 | ||
1680 | if (tracing_disabled || tracing_selftest_running) | |
e36c5458 | 1681 | return; |
03889384 SR |
1682 | |
1683 | local_save_flags(flags); | |
1684 | ||
c142be8e SRRH |
1685 | /* |
1686 | * Skip 3 more, seems to get us at the caller of | |
1687 | * this function. | |
1688 | */ | |
1689 | skip += 3; | |
1690 | __ftrace_trace_stack(global_trace.trace_buffer.buffer, | |
1691 | flags, skip, preempt_count(), NULL); | |
03889384 SR |
1692 | } |
1693 | ||
91e86e56 SR |
1694 | static DEFINE_PER_CPU(int, user_stack_count); |
1695 | ||
e77405ad SR |
1696 | void |
1697 | ftrace_trace_userstack(struct ring_buffer *buffer, unsigned long flags, int pc) | |
02b67518 | 1698 | { |
e1112b4d | 1699 | struct ftrace_event_call *call = &event_user_stack; |
8d7c6a96 | 1700 | struct ring_buffer_event *event; |
02b67518 TE |
1701 | struct userstack_entry *entry; |
1702 | struct stack_trace trace; | |
02b67518 TE |
1703 | |
1704 | if (!(trace_flags & TRACE_ITER_USERSTACKTRACE)) | |
1705 | return; | |
1706 | ||
b6345879 SR |
1707 | /* |
1708 | * NMIs can not handle page faults, even with fix ups. | |
1709 | * The save user stack can (and often does) fault. | |
1710 | */ | |
1711 | if (unlikely(in_nmi())) | |
1712 | return; | |
02b67518 | 1713 | |
91e86e56 SR |
1714 | /* |
1715 | * prevent recursion, since the user stack tracing may | |
1716 | * trigger other kernel events. | |
1717 | */ | |
1718 | preempt_disable(); | |
1719 | if (__this_cpu_read(user_stack_count)) | |
1720 | goto out; | |
1721 | ||
1722 | __this_cpu_inc(user_stack_count); | |
1723 | ||
e77405ad | 1724 | event = trace_buffer_lock_reserve(buffer, TRACE_USER_STACK, |
51a763dd | 1725 | sizeof(*entry), flags, pc); |
02b67518 | 1726 | if (!event) |
1dbd1951 | 1727 | goto out_drop_count; |
02b67518 | 1728 | entry = ring_buffer_event_data(event); |
02b67518 | 1729 | |
48659d31 | 1730 | entry->tgid = current->tgid; |
02b67518 TE |
1731 | memset(&entry->caller, 0, sizeof(entry->caller)); |
1732 | ||
1733 | trace.nr_entries = 0; | |
1734 | trace.max_entries = FTRACE_STACK_ENTRIES; | |
1735 | trace.skip = 0; | |
1736 | trace.entries = entry->caller; | |
1737 | ||
1738 | save_stack_trace_user(&trace); | |
e77405ad | 1739 | if (!filter_check_discard(call, entry, buffer, event)) |
7ffbd48d | 1740 | __buffer_unlock_commit(buffer, event); |
91e86e56 | 1741 | |
1dbd1951 | 1742 | out_drop_count: |
91e86e56 | 1743 | __this_cpu_dec(user_stack_count); |
91e86e56 SR |
1744 | out: |
1745 | preempt_enable(); | |
02b67518 TE |
1746 | } |
1747 | ||
4fd27358 HE |
1748 | #ifdef UNUSED |
1749 | static void __trace_userstack(struct trace_array *tr, unsigned long flags) | |
02b67518 | 1750 | { |
7be42151 | 1751 | ftrace_trace_userstack(tr, flags, preempt_count()); |
02b67518 | 1752 | } |
4fd27358 | 1753 | #endif /* UNUSED */ |
02b67518 | 1754 | |
c0a0d0d3 FW |
1755 | #endif /* CONFIG_STACKTRACE */ |
1756 | ||
07d777fe SR |
1757 | /* created for use with alloc_percpu */ |
1758 | struct trace_buffer_struct { | |
1759 | char buffer[TRACE_BUF_SIZE]; | |
1760 | }; | |
1761 | ||
1762 | static struct trace_buffer_struct *trace_percpu_buffer; | |
1763 | static struct trace_buffer_struct *trace_percpu_sirq_buffer; | |
1764 | static struct trace_buffer_struct *trace_percpu_irq_buffer; | |
1765 | static struct trace_buffer_struct *trace_percpu_nmi_buffer; | |
1766 | ||
1767 | /* | |
1768 | * The buffer used is dependent on the context. There is a per cpu | |
1769 | * buffer for normal context, softirq contex, hard irq context and | |
1770 | * for NMI context. Thise allows for lockless recording. | |
1771 | * | |
1772 | * Note, if the buffers failed to be allocated, then this returns NULL | |
1773 | */ | |
1774 | static char *get_trace_buf(void) | |
1775 | { | |
1776 | struct trace_buffer_struct *percpu_buffer; | |
07d777fe SR |
1777 | |
1778 | /* | |
1779 | * If we have allocated per cpu buffers, then we do not | |
1780 | * need to do any locking. | |
1781 | */ | |
1782 | if (in_nmi()) | |
1783 | percpu_buffer = trace_percpu_nmi_buffer; | |
1784 | else if (in_irq()) | |
1785 | percpu_buffer = trace_percpu_irq_buffer; | |
1786 | else if (in_softirq()) | |
1787 | percpu_buffer = trace_percpu_sirq_buffer; | |
1788 | else | |
1789 | percpu_buffer = trace_percpu_buffer; | |
1790 | ||
1791 | if (!percpu_buffer) | |
1792 | return NULL; | |
1793 | ||
d8a0349c | 1794 | return this_cpu_ptr(&percpu_buffer->buffer[0]); |
07d777fe SR |
1795 | } |
1796 | ||
1797 | static int alloc_percpu_trace_buffer(void) | |
1798 | { | |
1799 | struct trace_buffer_struct *buffers; | |
1800 | struct trace_buffer_struct *sirq_buffers; | |
1801 | struct trace_buffer_struct *irq_buffers; | |
1802 | struct trace_buffer_struct *nmi_buffers; | |
1803 | ||
1804 | buffers = alloc_percpu(struct trace_buffer_struct); | |
1805 | if (!buffers) | |
1806 | goto err_warn; | |
1807 | ||
1808 | sirq_buffers = alloc_percpu(struct trace_buffer_struct); | |
1809 | if (!sirq_buffers) | |
1810 | goto err_sirq; | |
1811 | ||
1812 | irq_buffers = alloc_percpu(struct trace_buffer_struct); | |
1813 | if (!irq_buffers) | |
1814 | goto err_irq; | |
1815 | ||
1816 | nmi_buffers = alloc_percpu(struct trace_buffer_struct); | |
1817 | if (!nmi_buffers) | |
1818 | goto err_nmi; | |
1819 | ||
1820 | trace_percpu_buffer = buffers; | |
1821 | trace_percpu_sirq_buffer = sirq_buffers; | |
1822 | trace_percpu_irq_buffer = irq_buffers; | |
1823 | trace_percpu_nmi_buffer = nmi_buffers; | |
1824 | ||
1825 | return 0; | |
1826 | ||
1827 | err_nmi: | |
1828 | free_percpu(irq_buffers); | |
1829 | err_irq: | |
1830 | free_percpu(sirq_buffers); | |
1831 | err_sirq: | |
1832 | free_percpu(buffers); | |
1833 | err_warn: | |
1834 | WARN(1, "Could not allocate percpu trace_printk buffer"); | |
1835 | return -ENOMEM; | |
1836 | } | |
1837 | ||
81698831 SR |
1838 | static int buffers_allocated; |
1839 | ||
07d777fe SR |
1840 | void trace_printk_init_buffers(void) |
1841 | { | |
07d777fe SR |
1842 | if (buffers_allocated) |
1843 | return; | |
1844 | ||
1845 | if (alloc_percpu_trace_buffer()) | |
1846 | return; | |
1847 | ||
1848 | pr_info("ftrace: Allocated trace_printk buffers\n"); | |
1849 | ||
b382ede6 SR |
1850 | /* Expand the buffers to set size */ |
1851 | tracing_update_buffers(); | |
1852 | ||
07d777fe | 1853 | buffers_allocated = 1; |
81698831 SR |
1854 | |
1855 | /* | |
1856 | * trace_printk_init_buffers() can be called by modules. | |
1857 | * If that happens, then we need to start cmdline recording | |
1858 | * directly here. If the global_trace.buffer is already | |
1859 | * allocated here, then this was called by module code. | |
1860 | */ | |
12883efb | 1861 | if (global_trace.trace_buffer.buffer) |
81698831 SR |
1862 | tracing_start_cmdline_record(); |
1863 | } | |
1864 | ||
1865 | void trace_printk_start_comm(void) | |
1866 | { | |
1867 | /* Start tracing comms if trace printk is set */ | |
1868 | if (!buffers_allocated) | |
1869 | return; | |
1870 | tracing_start_cmdline_record(); | |
1871 | } | |
1872 | ||
1873 | static void trace_printk_start_stop_comm(int enabled) | |
1874 | { | |
1875 | if (!buffers_allocated) | |
1876 | return; | |
1877 | ||
1878 | if (enabled) | |
1879 | tracing_start_cmdline_record(); | |
1880 | else | |
1881 | tracing_stop_cmdline_record(); | |
07d777fe SR |
1882 | } |
1883 | ||
769b0441 | 1884 | /** |
48ead020 | 1885 | * trace_vbprintk - write binary msg to tracing buffer |
769b0441 FW |
1886 | * |
1887 | */ | |
40ce74f1 | 1888 | int trace_vbprintk(unsigned long ip, const char *fmt, va_list args) |
769b0441 | 1889 | { |
e1112b4d | 1890 | struct ftrace_event_call *call = &event_bprint; |
769b0441 | 1891 | struct ring_buffer_event *event; |
e77405ad | 1892 | struct ring_buffer *buffer; |
769b0441 | 1893 | struct trace_array *tr = &global_trace; |
48ead020 | 1894 | struct bprint_entry *entry; |
769b0441 | 1895 | unsigned long flags; |
07d777fe SR |
1896 | char *tbuffer; |
1897 | int len = 0, size, pc; | |
769b0441 FW |
1898 | |
1899 | if (unlikely(tracing_selftest_running || tracing_disabled)) | |
1900 | return 0; | |
1901 | ||
1902 | /* Don't pollute graph traces with trace_vprintk internals */ | |
1903 | pause_graph_tracing(); | |
1904 | ||
1905 | pc = preempt_count(); | |
5168ae50 | 1906 | preempt_disable_notrace(); |
769b0441 | 1907 | |
07d777fe SR |
1908 | tbuffer = get_trace_buf(); |
1909 | if (!tbuffer) { | |
1910 | len = 0; | |
769b0441 | 1911 | goto out; |
07d777fe | 1912 | } |
769b0441 | 1913 | |
07d777fe | 1914 | len = vbin_printf((u32 *)tbuffer, TRACE_BUF_SIZE/sizeof(int), fmt, args); |
769b0441 | 1915 | |
07d777fe SR |
1916 | if (len > TRACE_BUF_SIZE/sizeof(int) || len < 0) |
1917 | goto out; | |
769b0441 | 1918 | |
07d777fe | 1919 | local_save_flags(flags); |
769b0441 | 1920 | size = sizeof(*entry) + sizeof(u32) * len; |
12883efb | 1921 | buffer = tr->trace_buffer.buffer; |
e77405ad SR |
1922 | event = trace_buffer_lock_reserve(buffer, TRACE_BPRINT, size, |
1923 | flags, pc); | |
769b0441 | 1924 | if (!event) |
07d777fe | 1925 | goto out; |
769b0441 FW |
1926 | entry = ring_buffer_event_data(event); |
1927 | entry->ip = ip; | |
769b0441 FW |
1928 | entry->fmt = fmt; |
1929 | ||
07d777fe | 1930 | memcpy(entry->buf, tbuffer, sizeof(u32) * len); |
d931369b | 1931 | if (!filter_check_discard(call, entry, buffer, event)) { |
7ffbd48d | 1932 | __buffer_unlock_commit(buffer, event); |
d931369b SR |
1933 | ftrace_trace_stack(buffer, flags, 6, pc); |
1934 | } | |
769b0441 | 1935 | |
769b0441 | 1936 | out: |
5168ae50 | 1937 | preempt_enable_notrace(); |
769b0441 FW |
1938 | unpause_graph_tracing(); |
1939 | ||
1940 | return len; | |
1941 | } | |
48ead020 FW |
1942 | EXPORT_SYMBOL_GPL(trace_vbprintk); |
1943 | ||
12883efb SRRH |
1944 | static int |
1945 | __trace_array_vprintk(struct ring_buffer *buffer, | |
1946 | unsigned long ip, const char *fmt, va_list args) | |
48ead020 | 1947 | { |
e1112b4d | 1948 | struct ftrace_event_call *call = &event_print; |
48ead020 | 1949 | struct ring_buffer_event *event; |
07d777fe | 1950 | int len = 0, size, pc; |
48ead020 | 1951 | struct print_entry *entry; |
07d777fe SR |
1952 | unsigned long flags; |
1953 | char *tbuffer; | |
48ead020 FW |
1954 | |
1955 | if (tracing_disabled || tracing_selftest_running) | |
1956 | return 0; | |
1957 | ||
07d777fe SR |
1958 | /* Don't pollute graph traces with trace_vprintk internals */ |
1959 | pause_graph_tracing(); | |
1960 | ||
48ead020 FW |
1961 | pc = preempt_count(); |
1962 | preempt_disable_notrace(); | |
48ead020 | 1963 | |
07d777fe SR |
1964 | |
1965 | tbuffer = get_trace_buf(); | |
1966 | if (!tbuffer) { | |
1967 | len = 0; | |
48ead020 | 1968 | goto out; |
07d777fe | 1969 | } |
48ead020 | 1970 | |
07d777fe SR |
1971 | len = vsnprintf(tbuffer, TRACE_BUF_SIZE, fmt, args); |
1972 | if (len > TRACE_BUF_SIZE) | |
1973 | goto out; | |
48ead020 | 1974 | |
07d777fe | 1975 | local_save_flags(flags); |
48ead020 | 1976 | size = sizeof(*entry) + len + 1; |
e77405ad | 1977 | event = trace_buffer_lock_reserve(buffer, TRACE_PRINT, size, |
07d777fe | 1978 | flags, pc); |
48ead020 | 1979 | if (!event) |
07d777fe | 1980 | goto out; |
48ead020 | 1981 | entry = ring_buffer_event_data(event); |
c13d2f7c | 1982 | entry->ip = ip; |
48ead020 | 1983 | |
07d777fe | 1984 | memcpy(&entry->buf, tbuffer, len); |
c13d2f7c | 1985 | entry->buf[len] = '\0'; |
d931369b | 1986 | if (!filter_check_discard(call, entry, buffer, event)) { |
7ffbd48d | 1987 | __buffer_unlock_commit(buffer, event); |
07d777fe | 1988 | ftrace_trace_stack(buffer, flags, 6, pc); |
d931369b | 1989 | } |
48ead020 FW |
1990 | out: |
1991 | preempt_enable_notrace(); | |
07d777fe | 1992 | unpause_graph_tracing(); |
48ead020 FW |
1993 | |
1994 | return len; | |
1995 | } | |
659372d3 | 1996 | |
12883efb SRRH |
1997 | int trace_array_vprintk(struct trace_array *tr, |
1998 | unsigned long ip, const char *fmt, va_list args) | |
1999 | { | |
2000 | return __trace_array_vprintk(tr->trace_buffer.buffer, ip, fmt, args); | |
2001 | } | |
2002 | ||
2003 | int trace_array_printk(struct trace_array *tr, | |
2004 | unsigned long ip, const char *fmt, ...) | |
2005 | { | |
2006 | int ret; | |
2007 | va_list ap; | |
2008 | ||
2009 | if (!(trace_flags & TRACE_ITER_PRINTK)) | |
2010 | return 0; | |
2011 | ||
2012 | va_start(ap, fmt); | |
2013 | ret = trace_array_vprintk(tr, ip, fmt, ap); | |
2014 | va_end(ap); | |
2015 | return ret; | |
2016 | } | |
2017 | ||
2018 | int trace_array_printk_buf(struct ring_buffer *buffer, | |
2019 | unsigned long ip, const char *fmt, ...) | |
2020 | { | |
2021 | int ret; | |
2022 | va_list ap; | |
2023 | ||
2024 | if (!(trace_flags & TRACE_ITER_PRINTK)) | |
2025 | return 0; | |
2026 | ||
2027 | va_start(ap, fmt); | |
2028 | ret = __trace_array_vprintk(buffer, ip, fmt, ap); | |
2029 | va_end(ap); | |
2030 | return ret; | |
2031 | } | |
2032 | ||
659372d3 SR |
2033 | int trace_vprintk(unsigned long ip, const char *fmt, va_list args) |
2034 | { | |
a813a159 | 2035 | return trace_array_vprintk(&global_trace, ip, fmt, args); |
659372d3 | 2036 | } |
769b0441 FW |
2037 | EXPORT_SYMBOL_GPL(trace_vprintk); |
2038 | ||
e2ac8ef5 | 2039 | static void trace_iterator_increment(struct trace_iterator *iter) |
5a90f577 | 2040 | { |
6d158a81 SR |
2041 | struct ring_buffer_iter *buf_iter = trace_buffer_iter(iter, iter->cpu); |
2042 | ||
5a90f577 | 2043 | iter->idx++; |
6d158a81 SR |
2044 | if (buf_iter) |
2045 | ring_buffer_read(buf_iter, NULL); | |
5a90f577 SR |
2046 | } |
2047 | ||
e309b41d | 2048 | static struct trace_entry * |
bc21b478 SR |
2049 | peek_next_entry(struct trace_iterator *iter, int cpu, u64 *ts, |
2050 | unsigned long *lost_events) | |
dd0e545f | 2051 | { |
3928a8a2 | 2052 | struct ring_buffer_event *event; |
6d158a81 | 2053 | struct ring_buffer_iter *buf_iter = trace_buffer_iter(iter, cpu); |
dd0e545f | 2054 | |
d769041f SR |
2055 | if (buf_iter) |
2056 | event = ring_buffer_iter_peek(buf_iter, ts); | |
2057 | else | |
12883efb | 2058 | event = ring_buffer_peek(iter->trace_buffer->buffer, cpu, ts, |
bc21b478 | 2059 | lost_events); |
d769041f | 2060 | |
4a9bd3f1 SR |
2061 | if (event) { |
2062 | iter->ent_size = ring_buffer_event_length(event); | |
2063 | return ring_buffer_event_data(event); | |
2064 | } | |
2065 | iter->ent_size = 0; | |
2066 | return NULL; | |
dd0e545f | 2067 | } |
d769041f | 2068 | |
dd0e545f | 2069 | static struct trace_entry * |
bc21b478 SR |
2070 | __find_next_entry(struct trace_iterator *iter, int *ent_cpu, |
2071 | unsigned long *missing_events, u64 *ent_ts) | |
bc0c38d1 | 2072 | { |
12883efb | 2073 | struct ring_buffer *buffer = iter->trace_buffer->buffer; |
bc0c38d1 | 2074 | struct trace_entry *ent, *next = NULL; |
aa27497c | 2075 | unsigned long lost_events = 0, next_lost = 0; |
b04cc6b1 | 2076 | int cpu_file = iter->cpu_file; |
3928a8a2 | 2077 | u64 next_ts = 0, ts; |
bc0c38d1 | 2078 | int next_cpu = -1; |
12b5da34 | 2079 | int next_size = 0; |
bc0c38d1 SR |
2080 | int cpu; |
2081 | ||
b04cc6b1 FW |
2082 | /* |
2083 | * If we are in a per_cpu trace file, don't bother by iterating over | |
2084 | * all cpu and peek directly. | |
2085 | */ | |
ae3b5093 | 2086 | if (cpu_file > RING_BUFFER_ALL_CPUS) { |
b04cc6b1 FW |
2087 | if (ring_buffer_empty_cpu(buffer, cpu_file)) |
2088 | return NULL; | |
bc21b478 | 2089 | ent = peek_next_entry(iter, cpu_file, ent_ts, missing_events); |
b04cc6b1 FW |
2090 | if (ent_cpu) |
2091 | *ent_cpu = cpu_file; | |
2092 | ||
2093 | return ent; | |
2094 | } | |
2095 | ||
ab46428c | 2096 | for_each_tracing_cpu(cpu) { |
dd0e545f | 2097 | |
3928a8a2 SR |
2098 | if (ring_buffer_empty_cpu(buffer, cpu)) |
2099 | continue; | |
dd0e545f | 2100 | |
bc21b478 | 2101 | ent = peek_next_entry(iter, cpu, &ts, &lost_events); |
dd0e545f | 2102 | |
cdd31cd2 IM |
2103 | /* |
2104 | * Pick the entry with the smallest timestamp: | |
2105 | */ | |
3928a8a2 | 2106 | if (ent && (!next || ts < next_ts)) { |
bc0c38d1 SR |
2107 | next = ent; |
2108 | next_cpu = cpu; | |
3928a8a2 | 2109 | next_ts = ts; |
bc21b478 | 2110 | next_lost = lost_events; |
12b5da34 | 2111 | next_size = iter->ent_size; |
bc0c38d1 SR |
2112 | } |
2113 | } | |
2114 | ||
12b5da34 SR |
2115 | iter->ent_size = next_size; |
2116 | ||
bc0c38d1 SR |
2117 | if (ent_cpu) |
2118 | *ent_cpu = next_cpu; | |
2119 | ||
3928a8a2 SR |
2120 | if (ent_ts) |
2121 | *ent_ts = next_ts; | |
2122 | ||
bc21b478 SR |
2123 | if (missing_events) |
2124 | *missing_events = next_lost; | |
2125 | ||
bc0c38d1 SR |
2126 | return next; |
2127 | } | |
2128 | ||
dd0e545f | 2129 | /* Find the next real entry, without updating the iterator itself */ |
c4a8e8be FW |
2130 | struct trace_entry *trace_find_next_entry(struct trace_iterator *iter, |
2131 | int *ent_cpu, u64 *ent_ts) | |
bc0c38d1 | 2132 | { |
bc21b478 | 2133 | return __find_next_entry(iter, ent_cpu, NULL, ent_ts); |
dd0e545f SR |
2134 | } |
2135 | ||
2136 | /* Find the next real entry, and increment the iterator to the next entry */ | |
955b61e5 | 2137 | void *trace_find_next_entry_inc(struct trace_iterator *iter) |
dd0e545f | 2138 | { |
bc21b478 SR |
2139 | iter->ent = __find_next_entry(iter, &iter->cpu, |
2140 | &iter->lost_events, &iter->ts); | |
dd0e545f | 2141 | |
3928a8a2 | 2142 | if (iter->ent) |
e2ac8ef5 | 2143 | trace_iterator_increment(iter); |
dd0e545f | 2144 | |
3928a8a2 | 2145 | return iter->ent ? iter : NULL; |
b3806b43 | 2146 | } |
bc0c38d1 | 2147 | |
e309b41d | 2148 | static void trace_consume(struct trace_iterator *iter) |
b3806b43 | 2149 | { |
12883efb | 2150 | ring_buffer_consume(iter->trace_buffer->buffer, iter->cpu, &iter->ts, |
bc21b478 | 2151 | &iter->lost_events); |
bc0c38d1 SR |
2152 | } |
2153 | ||
e309b41d | 2154 | static void *s_next(struct seq_file *m, void *v, loff_t *pos) |
bc0c38d1 SR |
2155 | { |
2156 | struct trace_iterator *iter = m->private; | |
bc0c38d1 | 2157 | int i = (int)*pos; |
4e3c3333 | 2158 | void *ent; |
bc0c38d1 | 2159 | |
a63ce5b3 SR |
2160 | WARN_ON_ONCE(iter->leftover); |
2161 | ||
bc0c38d1 SR |
2162 | (*pos)++; |
2163 | ||
2164 | /* can't go backwards */ | |
2165 | if (iter->idx > i) | |
2166 | return NULL; | |
2167 | ||
2168 | if (iter->idx < 0) | |
955b61e5 | 2169 | ent = trace_find_next_entry_inc(iter); |
bc0c38d1 SR |
2170 | else |
2171 | ent = iter; | |
2172 | ||
2173 | while (ent && iter->idx < i) | |
955b61e5 | 2174 | ent = trace_find_next_entry_inc(iter); |
bc0c38d1 SR |
2175 | |
2176 | iter->pos = *pos; | |
2177 | ||
bc0c38d1 SR |
2178 | return ent; |
2179 | } | |
2180 | ||
955b61e5 | 2181 | void tracing_iter_reset(struct trace_iterator *iter, int cpu) |
2f26ebd5 | 2182 | { |
2f26ebd5 SR |
2183 | struct ring_buffer_event *event; |
2184 | struct ring_buffer_iter *buf_iter; | |
2185 | unsigned long entries = 0; | |
2186 | u64 ts; | |
2187 | ||
12883efb | 2188 | per_cpu_ptr(iter->trace_buffer->data, cpu)->skipped_entries = 0; |
2f26ebd5 | 2189 | |
6d158a81 SR |
2190 | buf_iter = trace_buffer_iter(iter, cpu); |
2191 | if (!buf_iter) | |
2f26ebd5 SR |
2192 | return; |
2193 | ||
2f26ebd5 SR |
2194 | ring_buffer_iter_reset(buf_iter); |
2195 | ||
2196 | /* | |
2197 | * We could have the case with the max latency tracers | |
2198 | * that a reset never took place on a cpu. This is evident | |
2199 | * by the timestamp being before the start of the buffer. | |
2200 | */ | |
2201 | while ((event = ring_buffer_iter_peek(buf_iter, &ts))) { | |
12883efb | 2202 | if (ts >= iter->trace_buffer->time_start) |
2f26ebd5 SR |
2203 | break; |
2204 | entries++; | |
2205 | ring_buffer_read(buf_iter, NULL); | |
2206 | } | |
2207 | ||
12883efb | 2208 | per_cpu_ptr(iter->trace_buffer->data, cpu)->skipped_entries = entries; |
2f26ebd5 SR |
2209 | } |
2210 | ||
d7350c3f | 2211 | /* |
d7350c3f FW |
2212 | * The current tracer is copied to avoid a global locking |
2213 | * all around. | |
2214 | */ | |
bc0c38d1 SR |
2215 | static void *s_start(struct seq_file *m, loff_t *pos) |
2216 | { | |
2217 | struct trace_iterator *iter = m->private; | |
2b6080f2 | 2218 | struct trace_array *tr = iter->tr; |
b04cc6b1 | 2219 | int cpu_file = iter->cpu_file; |
bc0c38d1 SR |
2220 | void *p = NULL; |
2221 | loff_t l = 0; | |
3928a8a2 | 2222 | int cpu; |
bc0c38d1 | 2223 | |
2fd196ec HT |
2224 | /* |
2225 | * copy the tracer to avoid using a global lock all around. | |
2226 | * iter->trace is a copy of current_trace, the pointer to the | |
2227 | * name may be used instead of a strcmp(), as iter->trace->name | |
2228 | * will point to the same string as current_trace->name. | |
2229 | */ | |
bc0c38d1 | 2230 | mutex_lock(&trace_types_lock); |
2b6080f2 SR |
2231 | if (unlikely(tr->current_trace && iter->trace->name != tr->current_trace->name)) |
2232 | *iter->trace = *tr->current_trace; | |
d7350c3f | 2233 | mutex_unlock(&trace_types_lock); |
bc0c38d1 | 2234 | |
12883efb | 2235 | #ifdef CONFIG_TRACER_MAX_TRACE |
debdd57f HT |
2236 | if (iter->snapshot && iter->trace->use_max_tr) |
2237 | return ERR_PTR(-EBUSY); | |
12883efb | 2238 | #endif |
debdd57f HT |
2239 | |
2240 | if (!iter->snapshot) | |
2241 | atomic_inc(&trace_record_cmdline_disabled); | |
bc0c38d1 | 2242 | |
bc0c38d1 SR |
2243 | if (*pos != iter->pos) { |
2244 | iter->ent = NULL; | |
2245 | iter->cpu = 0; | |
2246 | iter->idx = -1; | |
2247 | ||
ae3b5093 | 2248 | if (cpu_file == RING_BUFFER_ALL_CPUS) { |
b04cc6b1 | 2249 | for_each_tracing_cpu(cpu) |
2f26ebd5 | 2250 | tracing_iter_reset(iter, cpu); |
b04cc6b1 | 2251 | } else |
2f26ebd5 | 2252 | tracing_iter_reset(iter, cpu_file); |
bc0c38d1 | 2253 | |
ac91d854 | 2254 | iter->leftover = 0; |
bc0c38d1 SR |
2255 | for (p = iter; p && l < *pos; p = s_next(m, p, &l)) |
2256 | ; | |
2257 | ||
2258 | } else { | |
a63ce5b3 SR |
2259 | /* |
2260 | * If we overflowed the seq_file before, then we want | |
2261 | * to just reuse the trace_seq buffer again. | |
2262 | */ | |
2263 | if (iter->leftover) | |
2264 | p = iter; | |
2265 | else { | |
2266 | l = *pos - 1; | |
2267 | p = s_next(m, p, &l); | |
2268 | } | |
bc0c38d1 SR |
2269 | } |
2270 | ||
4f535968 | 2271 | trace_event_read_lock(); |
7e53bd42 | 2272 | trace_access_lock(cpu_file); |
bc0c38d1 SR |
2273 | return p; |
2274 | } | |
2275 | ||
2276 | static void s_stop(struct seq_file *m, void *p) | |
2277 | { | |
7e53bd42 LJ |
2278 | struct trace_iterator *iter = m->private; |
2279 | ||
12883efb | 2280 | #ifdef CONFIG_TRACER_MAX_TRACE |
debdd57f HT |
2281 | if (iter->snapshot && iter->trace->use_max_tr) |
2282 | return; | |
12883efb | 2283 | #endif |
debdd57f HT |
2284 | |
2285 | if (!iter->snapshot) | |
2286 | atomic_dec(&trace_record_cmdline_disabled); | |
12883efb | 2287 | |
7e53bd42 | 2288 | trace_access_unlock(iter->cpu_file); |
4f535968 | 2289 | trace_event_read_unlock(); |
bc0c38d1 SR |
2290 | } |
2291 | ||
39eaf7ef | 2292 | static void |
12883efb SRRH |
2293 | get_total_entries(struct trace_buffer *buf, |
2294 | unsigned long *total, unsigned long *entries) | |
39eaf7ef SR |
2295 | { |
2296 | unsigned long count; | |
2297 | int cpu; | |
2298 | ||
2299 | *total = 0; | |
2300 | *entries = 0; | |
2301 | ||
2302 | for_each_tracing_cpu(cpu) { | |
12883efb | 2303 | count = ring_buffer_entries_cpu(buf->buffer, cpu); |
39eaf7ef SR |
2304 | /* |
2305 | * If this buffer has skipped entries, then we hold all | |
2306 | * entries for the trace and we need to ignore the | |
2307 | * ones before the time stamp. | |
2308 | */ | |
12883efb SRRH |
2309 | if (per_cpu_ptr(buf->data, cpu)->skipped_entries) { |
2310 | count -= per_cpu_ptr(buf->data, cpu)->skipped_entries; | |
39eaf7ef SR |
2311 | /* total is the same as the entries */ |
2312 | *total += count; | |
2313 | } else | |
2314 | *total += count + | |
12883efb | 2315 | ring_buffer_overrun_cpu(buf->buffer, cpu); |
39eaf7ef SR |
2316 | *entries += count; |
2317 | } | |
2318 | } | |
2319 | ||
e309b41d | 2320 | static void print_lat_help_header(struct seq_file *m) |
bc0c38d1 | 2321 | { |
a6168353 ME |
2322 | seq_puts(m, "# _------=> CPU# \n"); |
2323 | seq_puts(m, "# / _-----=> irqs-off \n"); | |
2324 | seq_puts(m, "# | / _----=> need-resched \n"); | |
2325 | seq_puts(m, "# || / _---=> hardirq/softirq \n"); | |
2326 | seq_puts(m, "# ||| / _--=> preempt-depth \n"); | |
e6e1e259 SR |
2327 | seq_puts(m, "# |||| / delay \n"); |
2328 | seq_puts(m, "# cmd pid ||||| time | caller \n"); | |
2329 | seq_puts(m, "# \\ / ||||| \\ | / \n"); | |
bc0c38d1 SR |
2330 | } |
2331 | ||
12883efb | 2332 | static void print_event_info(struct trace_buffer *buf, struct seq_file *m) |
bc0c38d1 | 2333 | { |
39eaf7ef SR |
2334 | unsigned long total; |
2335 | unsigned long entries; | |
2336 | ||
12883efb | 2337 | get_total_entries(buf, &total, &entries); |
39eaf7ef SR |
2338 | seq_printf(m, "# entries-in-buffer/entries-written: %lu/%lu #P:%d\n", |
2339 | entries, total, num_online_cpus()); | |
2340 | seq_puts(m, "#\n"); | |
2341 | } | |
2342 | ||
12883efb | 2343 | static void print_func_help_header(struct trace_buffer *buf, struct seq_file *m) |
39eaf7ef | 2344 | { |
12883efb | 2345 | print_event_info(buf, m); |
77271ce4 | 2346 | seq_puts(m, "# TASK-PID CPU# TIMESTAMP FUNCTION\n"); |
a6168353 | 2347 | seq_puts(m, "# | | | | |\n"); |
bc0c38d1 SR |
2348 | } |
2349 | ||
12883efb | 2350 | static void print_func_help_header_irq(struct trace_buffer *buf, struct seq_file *m) |
77271ce4 | 2351 | { |
12883efb | 2352 | print_event_info(buf, m); |
77271ce4 SR |
2353 | seq_puts(m, "# _-----=> irqs-off\n"); |
2354 | seq_puts(m, "# / _----=> need-resched\n"); | |
2355 | seq_puts(m, "# | / _---=> hardirq/softirq\n"); | |
2356 | seq_puts(m, "# || / _--=> preempt-depth\n"); | |
2357 | seq_puts(m, "# ||| / delay\n"); | |
2358 | seq_puts(m, "# TASK-PID CPU# |||| TIMESTAMP FUNCTION\n"); | |
2359 | seq_puts(m, "# | | | |||| | |\n"); | |
2360 | } | |
bc0c38d1 | 2361 | |
62b915f1 | 2362 | void |
bc0c38d1 SR |
2363 | print_trace_header(struct seq_file *m, struct trace_iterator *iter) |
2364 | { | |
2365 | unsigned long sym_flags = (trace_flags & TRACE_ITER_SYM_MASK); | |
12883efb SRRH |
2366 | struct trace_buffer *buf = iter->trace_buffer; |
2367 | struct trace_array_cpu *data = per_cpu_ptr(buf->data, buf->cpu); | |
2b6080f2 | 2368 | struct tracer *type = iter->trace; |
39eaf7ef SR |
2369 | unsigned long entries; |
2370 | unsigned long total; | |
bc0c38d1 SR |
2371 | const char *name = "preemption"; |
2372 | ||
d840f718 | 2373 | name = type->name; |
bc0c38d1 | 2374 | |
12883efb | 2375 | get_total_entries(buf, &total, &entries); |
bc0c38d1 | 2376 | |
888b55dc | 2377 | seq_printf(m, "# %s latency trace v1.1.5 on %s\n", |
bc0c38d1 | 2378 | name, UTS_RELEASE); |
888b55dc | 2379 | seq_puts(m, "# -----------------------------------" |
bc0c38d1 | 2380 | "---------------------------------\n"); |
888b55dc | 2381 | seq_printf(m, "# latency: %lu us, #%lu/%lu, CPU#%d |" |
bc0c38d1 | 2382 | " (M:%s VP:%d, KP:%d, SP:%d HP:%d", |
57f50be1 | 2383 | nsecs_to_usecs(data->saved_latency), |
bc0c38d1 | 2384 | entries, |
4c11d7ae | 2385 | total, |
12883efb | 2386 | buf->cpu, |
bc0c38d1 SR |
2387 | #if defined(CONFIG_PREEMPT_NONE) |
2388 | "server", | |
2389 | #elif defined(CONFIG_PREEMPT_VOLUNTARY) | |
2390 | "desktop", | |
b5c21b45 | 2391 | #elif defined(CONFIG_PREEMPT) |
bc0c38d1 SR |
2392 | "preempt", |
2393 | #else | |
2394 | "unknown", | |
2395 | #endif | |
2396 | /* These are reserved for later use */ | |
2397 | 0, 0, 0, 0); | |
2398 | #ifdef CONFIG_SMP | |
2399 | seq_printf(m, " #P:%d)\n", num_online_cpus()); | |
2400 | #else | |
2401 | seq_puts(m, ")\n"); | |
2402 | #endif | |
888b55dc KM |
2403 | seq_puts(m, "# -----------------\n"); |
2404 | seq_printf(m, "# | task: %.16s-%d " | |
bc0c38d1 | 2405 | "(uid:%d nice:%ld policy:%ld rt_prio:%ld)\n", |
d20b92ab EB |
2406 | data->comm, data->pid, |
2407 | from_kuid_munged(seq_user_ns(m), data->uid), data->nice, | |
bc0c38d1 | 2408 | data->policy, data->rt_priority); |
888b55dc | 2409 | seq_puts(m, "# -----------------\n"); |
bc0c38d1 SR |
2410 | |
2411 | if (data->critical_start) { | |
888b55dc | 2412 | seq_puts(m, "# => started at: "); |
214023c3 SR |
2413 | seq_print_ip_sym(&iter->seq, data->critical_start, sym_flags); |
2414 | trace_print_seq(m, &iter->seq); | |
888b55dc | 2415 | seq_puts(m, "\n# => ended at: "); |
214023c3 SR |
2416 | seq_print_ip_sym(&iter->seq, data->critical_end, sym_flags); |
2417 | trace_print_seq(m, &iter->seq); | |
8248ac05 | 2418 | seq_puts(m, "\n#\n"); |
bc0c38d1 SR |
2419 | } |
2420 | ||
888b55dc | 2421 | seq_puts(m, "#\n"); |
bc0c38d1 SR |
2422 | } |
2423 | ||
a309720c SR |
2424 | static void test_cpu_buff_start(struct trace_iterator *iter) |
2425 | { | |
2426 | struct trace_seq *s = &iter->seq; | |
2427 | ||
12ef7d44 SR |
2428 | if (!(trace_flags & TRACE_ITER_ANNOTATE)) |
2429 | return; | |
2430 | ||
2431 | if (!(iter->iter_flags & TRACE_FILE_ANNOTATE)) | |
2432 | return; | |
2433 | ||
4462344e | 2434 | if (cpumask_test_cpu(iter->cpu, iter->started)) |
a309720c SR |
2435 | return; |
2436 | ||
12883efb | 2437 | if (per_cpu_ptr(iter->trace_buffer->data, iter->cpu)->skipped_entries) |
2f26ebd5 SR |
2438 | return; |
2439 | ||
4462344e | 2440 | cpumask_set_cpu(iter->cpu, iter->started); |
b0dfa978 FW |
2441 | |
2442 | /* Don't print started cpu buffer for the first entry of the trace */ | |
2443 | if (iter->idx > 1) | |
2444 | trace_seq_printf(s, "##### CPU %u buffer started ####\n", | |
2445 | iter->cpu); | |
a309720c SR |
2446 | } |
2447 | ||
2c4f035f | 2448 | static enum print_line_t print_trace_fmt(struct trace_iterator *iter) |
bc0c38d1 | 2449 | { |
214023c3 | 2450 | struct trace_seq *s = &iter->seq; |
bc0c38d1 | 2451 | unsigned long sym_flags = (trace_flags & TRACE_ITER_SYM_MASK); |
4e3c3333 | 2452 | struct trace_entry *entry; |
f633cef0 | 2453 | struct trace_event *event; |
bc0c38d1 | 2454 | |
4e3c3333 | 2455 | entry = iter->ent; |
dd0e545f | 2456 | |
a309720c SR |
2457 | test_cpu_buff_start(iter); |
2458 | ||
c4a8e8be | 2459 | event = ftrace_find_event(entry->type); |
bc0c38d1 | 2460 | |
c4a8e8be | 2461 | if (trace_flags & TRACE_ITER_CONTEXT_INFO) { |
27d48be8 SR |
2462 | if (iter->iter_flags & TRACE_FILE_LAT_FMT) { |
2463 | if (!trace_print_lat_context(iter)) | |
2464 | goto partial; | |
2465 | } else { | |
2466 | if (!trace_print_context(iter)) | |
2467 | goto partial; | |
2468 | } | |
c4a8e8be | 2469 | } |
bc0c38d1 | 2470 | |
268ccda0 | 2471 | if (event) |
a9a57763 | 2472 | return event->funcs->trace(iter, sym_flags, event); |
d9793bd8 ACM |
2473 | |
2474 | if (!trace_seq_printf(s, "Unknown type %d\n", entry->type)) | |
2475 | goto partial; | |
02b67518 | 2476 | |
2c4f035f | 2477 | return TRACE_TYPE_HANDLED; |
d9793bd8 ACM |
2478 | partial: |
2479 | return TRACE_TYPE_PARTIAL_LINE; | |
bc0c38d1 SR |
2480 | } |
2481 | ||
2c4f035f | 2482 | static enum print_line_t print_raw_fmt(struct trace_iterator *iter) |
f9896bf3 IM |
2483 | { |
2484 | struct trace_seq *s = &iter->seq; | |
2485 | struct trace_entry *entry; | |
f633cef0 | 2486 | struct trace_event *event; |
f9896bf3 IM |
2487 | |
2488 | entry = iter->ent; | |
dd0e545f | 2489 | |
c4a8e8be | 2490 | if (trace_flags & TRACE_ITER_CONTEXT_INFO) { |
d9793bd8 ACM |
2491 | if (!trace_seq_printf(s, "%d %d %llu ", |
2492 | entry->pid, iter->cpu, iter->ts)) | |
2493 | goto partial; | |
c4a8e8be | 2494 | } |
f9896bf3 | 2495 | |
f633cef0 | 2496 | event = ftrace_find_event(entry->type); |
268ccda0 | 2497 | if (event) |
a9a57763 | 2498 | return event->funcs->raw(iter, 0, event); |
d9793bd8 ACM |
2499 | |
2500 | if (!trace_seq_printf(s, "%d ?\n", entry->type)) | |
2501 | goto partial; | |
777e208d | 2502 | |
2c4f035f | 2503 | return TRACE_TYPE_HANDLED; |
d9793bd8 ACM |
2504 | partial: |
2505 | return TRACE_TYPE_PARTIAL_LINE; | |
f9896bf3 IM |
2506 | } |
2507 | ||
2c4f035f | 2508 | static enum print_line_t print_hex_fmt(struct trace_iterator *iter) |
5e3ca0ec IM |
2509 | { |
2510 | struct trace_seq *s = &iter->seq; | |
2511 | unsigned char newline = '\n'; | |
2512 | struct trace_entry *entry; | |
f633cef0 | 2513 | struct trace_event *event; |
5e3ca0ec IM |
2514 | |
2515 | entry = iter->ent; | |
dd0e545f | 2516 | |
c4a8e8be FW |
2517 | if (trace_flags & TRACE_ITER_CONTEXT_INFO) { |
2518 | SEQ_PUT_HEX_FIELD_RET(s, entry->pid); | |
2519 | SEQ_PUT_HEX_FIELD_RET(s, iter->cpu); | |
2520 | SEQ_PUT_HEX_FIELD_RET(s, iter->ts); | |
2521 | } | |
5e3ca0ec | 2522 | |
f633cef0 | 2523 | event = ftrace_find_event(entry->type); |
268ccda0 | 2524 | if (event) { |
a9a57763 | 2525 | enum print_line_t ret = event->funcs->hex(iter, 0, event); |
d9793bd8 ACM |
2526 | if (ret != TRACE_TYPE_HANDLED) |
2527 | return ret; | |
2528 | } | |
7104f300 | 2529 | |
5e3ca0ec IM |
2530 | SEQ_PUT_FIELD_RET(s, newline); |
2531 | ||
2c4f035f | 2532 | return TRACE_TYPE_HANDLED; |
5e3ca0ec IM |
2533 | } |
2534 | ||
2c4f035f | 2535 | static enum print_line_t print_bin_fmt(struct trace_iterator *iter) |
cb0f12aa IM |
2536 | { |
2537 | struct trace_seq *s = &iter->seq; | |
2538 | struct trace_entry *entry; | |
f633cef0 | 2539 | struct trace_event *event; |
cb0f12aa IM |
2540 | |
2541 | entry = iter->ent; | |
dd0e545f | 2542 | |
c4a8e8be FW |
2543 | if (trace_flags & TRACE_ITER_CONTEXT_INFO) { |
2544 | SEQ_PUT_FIELD_RET(s, entry->pid); | |
1830b52d | 2545 | SEQ_PUT_FIELD_RET(s, iter->cpu); |
c4a8e8be FW |
2546 | SEQ_PUT_FIELD_RET(s, iter->ts); |
2547 | } | |
cb0f12aa | 2548 | |
f633cef0 | 2549 | event = ftrace_find_event(entry->type); |
a9a57763 SR |
2550 | return event ? event->funcs->binary(iter, 0, event) : |
2551 | TRACE_TYPE_HANDLED; | |
cb0f12aa IM |
2552 | } |
2553 | ||
62b915f1 | 2554 | int trace_empty(struct trace_iterator *iter) |
bc0c38d1 | 2555 | { |
6d158a81 | 2556 | struct ring_buffer_iter *buf_iter; |
bc0c38d1 SR |
2557 | int cpu; |
2558 | ||
9aba60fe | 2559 | /* If we are looking at one CPU buffer, only check that one */ |
ae3b5093 | 2560 | if (iter->cpu_file != RING_BUFFER_ALL_CPUS) { |
9aba60fe | 2561 | cpu = iter->cpu_file; |
6d158a81 SR |
2562 | buf_iter = trace_buffer_iter(iter, cpu); |
2563 | if (buf_iter) { | |
2564 | if (!ring_buffer_iter_empty(buf_iter)) | |
9aba60fe SR |
2565 | return 0; |
2566 | } else { | |
12883efb | 2567 | if (!ring_buffer_empty_cpu(iter->trace_buffer->buffer, cpu)) |
9aba60fe SR |
2568 | return 0; |
2569 | } | |
2570 | return 1; | |
2571 | } | |
2572 | ||
ab46428c | 2573 | for_each_tracing_cpu(cpu) { |
6d158a81 SR |
2574 | buf_iter = trace_buffer_iter(iter, cpu); |
2575 | if (buf_iter) { | |
2576 | if (!ring_buffer_iter_empty(buf_iter)) | |
d769041f SR |
2577 | return 0; |
2578 | } else { | |
12883efb | 2579 | if (!ring_buffer_empty_cpu(iter->trace_buffer->buffer, cpu)) |
d769041f SR |
2580 | return 0; |
2581 | } | |
bc0c38d1 | 2582 | } |
d769041f | 2583 | |
797d3712 | 2584 | return 1; |
bc0c38d1 SR |
2585 | } |
2586 | ||
4f535968 | 2587 | /* Called with trace_event_read_lock() held. */ |
955b61e5 | 2588 | enum print_line_t print_trace_line(struct trace_iterator *iter) |
f9896bf3 | 2589 | { |
2c4f035f FW |
2590 | enum print_line_t ret; |
2591 | ||
ee5e51f5 JO |
2592 | if (iter->lost_events && |
2593 | !trace_seq_printf(&iter->seq, "CPU:%d [LOST %lu EVENTS]\n", | |
2594 | iter->cpu, iter->lost_events)) | |
2595 | return TRACE_TYPE_PARTIAL_LINE; | |
bc21b478 | 2596 | |
2c4f035f FW |
2597 | if (iter->trace && iter->trace->print_line) { |
2598 | ret = iter->trace->print_line(iter); | |
2599 | if (ret != TRACE_TYPE_UNHANDLED) | |
2600 | return ret; | |
2601 | } | |
72829bc3 | 2602 | |
09ae7234 SRRH |
2603 | if (iter->ent->type == TRACE_BPUTS && |
2604 | trace_flags & TRACE_ITER_PRINTK && | |
2605 | trace_flags & TRACE_ITER_PRINTK_MSGONLY) | |
2606 | return trace_print_bputs_msg_only(iter); | |
2607 | ||
48ead020 FW |
2608 | if (iter->ent->type == TRACE_BPRINT && |
2609 | trace_flags & TRACE_ITER_PRINTK && | |
2610 | trace_flags & TRACE_ITER_PRINTK_MSGONLY) | |
5ef841f6 | 2611 | return trace_print_bprintk_msg_only(iter); |
48ead020 | 2612 | |
66896a85 FW |
2613 | if (iter->ent->type == TRACE_PRINT && |
2614 | trace_flags & TRACE_ITER_PRINTK && | |
2615 | trace_flags & TRACE_ITER_PRINTK_MSGONLY) | |
5ef841f6 | 2616 | return trace_print_printk_msg_only(iter); |
66896a85 | 2617 | |
cb0f12aa IM |
2618 | if (trace_flags & TRACE_ITER_BIN) |
2619 | return print_bin_fmt(iter); | |
2620 | ||
5e3ca0ec IM |
2621 | if (trace_flags & TRACE_ITER_HEX) |
2622 | return print_hex_fmt(iter); | |
2623 | ||
f9896bf3 IM |
2624 | if (trace_flags & TRACE_ITER_RAW) |
2625 | return print_raw_fmt(iter); | |
2626 | ||
f9896bf3 IM |
2627 | return print_trace_fmt(iter); |
2628 | } | |
2629 | ||
7e9a49ef JO |
2630 | void trace_latency_header(struct seq_file *m) |
2631 | { | |
2632 | struct trace_iterator *iter = m->private; | |
2633 | ||
2634 | /* print nothing if the buffers are empty */ | |
2635 | if (trace_empty(iter)) | |
2636 | return; | |
2637 | ||
2638 | if (iter->iter_flags & TRACE_FILE_LAT_FMT) | |
2639 | print_trace_header(m, iter); | |
2640 | ||
2641 | if (!(trace_flags & TRACE_ITER_VERBOSE)) | |
2642 | print_lat_help_header(m); | |
2643 | } | |
2644 | ||
62b915f1 JO |
2645 | void trace_default_header(struct seq_file *m) |
2646 | { | |
2647 | struct trace_iterator *iter = m->private; | |
2648 | ||
f56e7f8e JO |
2649 | if (!(trace_flags & TRACE_ITER_CONTEXT_INFO)) |
2650 | return; | |
2651 | ||
62b915f1 JO |
2652 | if (iter->iter_flags & TRACE_FILE_LAT_FMT) { |
2653 | /* print nothing if the buffers are empty */ | |
2654 | if (trace_empty(iter)) | |
2655 | return; | |
2656 | print_trace_header(m, iter); | |
2657 | if (!(trace_flags & TRACE_ITER_VERBOSE)) | |
2658 | print_lat_help_header(m); | |
2659 | } else { | |
77271ce4 SR |
2660 | if (!(trace_flags & TRACE_ITER_VERBOSE)) { |
2661 | if (trace_flags & TRACE_ITER_IRQ_INFO) | |
12883efb | 2662 | print_func_help_header_irq(iter->trace_buffer, m); |
77271ce4 | 2663 | else |
12883efb | 2664 | print_func_help_header(iter->trace_buffer, m); |
77271ce4 | 2665 | } |
62b915f1 JO |
2666 | } |
2667 | } | |
2668 | ||
e0a413f6 SR |
2669 | static void test_ftrace_alive(struct seq_file *m) |
2670 | { | |
2671 | if (!ftrace_is_dead()) | |
2672 | return; | |
2673 | seq_printf(m, "# WARNING: FUNCTION TRACING IS CORRUPTED\n"); | |
2674 | seq_printf(m, "# MAY BE MISSING FUNCTION EVENTS\n"); | |
2675 | } | |
2676 | ||
d8741e2e | 2677 | #ifdef CONFIG_TRACER_MAX_TRACE |
f1affcaa | 2678 | static void show_snapshot_main_help(struct seq_file *m) |
d8741e2e | 2679 | { |
d8741e2e SRRH |
2680 | seq_printf(m, "# echo 0 > snapshot : Clears and frees snapshot buffer\n"); |
2681 | seq_printf(m, "# echo 1 > snapshot : Allocates snapshot buffer, if not already allocated.\n"); | |
2682 | seq_printf(m, "# Takes a snapshot of the main buffer.\n"); | |
2683 | seq_printf(m, "# echo 2 > snapshot : Clears snapshot buffer (but does not allocate)\n"); | |
2684 | seq_printf(m, "# (Doesn't have to be '2' works with any number that\n"); | |
2685 | seq_printf(m, "# is not a '0' or '1')\n"); | |
2686 | } | |
f1affcaa SRRH |
2687 | |
2688 | static void show_snapshot_percpu_help(struct seq_file *m) | |
2689 | { | |
2690 | seq_printf(m, "# echo 0 > snapshot : Invalid for per_cpu snapshot file.\n"); | |
2691 | #ifdef CONFIG_RING_BUFFER_ALLOW_SWAP | |
2692 | seq_printf(m, "# echo 1 > snapshot : Allocates snapshot buffer, if not already allocated.\n"); | |
2693 | seq_printf(m, "# Takes a snapshot of the main buffer for this cpu.\n"); | |
2694 | #else | |
2695 | seq_printf(m, "# echo 1 > snapshot : Not supported with this kernel.\n"); | |
2696 | seq_printf(m, "# Must use main snapshot file to allocate.\n"); | |
2697 | #endif | |
2698 | seq_printf(m, "# echo 2 > snapshot : Clears this cpu's snapshot buffer (but does not allocate)\n"); | |
2699 | seq_printf(m, "# (Doesn't have to be '2' works with any number that\n"); | |
2700 | seq_printf(m, "# is not a '0' or '1')\n"); | |
2701 | } | |
2702 | ||
d8741e2e SRRH |
2703 | static void print_snapshot_help(struct seq_file *m, struct trace_iterator *iter) |
2704 | { | |
45ad21ca | 2705 | if (iter->tr->allocated_snapshot) |
d8741e2e SRRH |
2706 | seq_printf(m, "#\n# * Snapshot is allocated *\n#\n"); |
2707 | else | |
2708 | seq_printf(m, "#\n# * Snapshot is freed *\n#\n"); | |
2709 | ||
2710 | seq_printf(m, "# Snapshot commands:\n"); | |
f1affcaa SRRH |
2711 | if (iter->cpu_file == RING_BUFFER_ALL_CPUS) |
2712 | show_snapshot_main_help(m); | |
2713 | else | |
2714 | show_snapshot_percpu_help(m); | |
d8741e2e SRRH |
2715 | } |
2716 | #else | |
2717 | /* Should never be called */ | |
2718 | static inline void print_snapshot_help(struct seq_file *m, struct trace_iterator *iter) { } | |
2719 | #endif | |
2720 | ||
bc0c38d1 SR |
2721 | static int s_show(struct seq_file *m, void *v) |
2722 | { | |
2723 | struct trace_iterator *iter = v; | |
a63ce5b3 | 2724 | int ret; |
bc0c38d1 SR |
2725 | |
2726 | if (iter->ent == NULL) { | |
2727 | if (iter->tr) { | |
2728 | seq_printf(m, "# tracer: %s\n", iter->trace->name); | |
2729 | seq_puts(m, "#\n"); | |
e0a413f6 | 2730 | test_ftrace_alive(m); |
bc0c38d1 | 2731 | } |
d8741e2e SRRH |
2732 | if (iter->snapshot && trace_empty(iter)) |
2733 | print_snapshot_help(m, iter); | |
2734 | else if (iter->trace && iter->trace->print_header) | |
8bba1bf5 | 2735 | iter->trace->print_header(m); |
62b915f1 JO |
2736 | else |
2737 | trace_default_header(m); | |
2738 | ||
a63ce5b3 SR |
2739 | } else if (iter->leftover) { |
2740 | /* | |
2741 | * If we filled the seq_file buffer earlier, we | |
2742 | * want to just show it now. | |
2743 | */ | |
2744 | ret = trace_print_seq(m, &iter->seq); | |
2745 | ||
2746 | /* ret should this time be zero, but you never know */ | |
2747 | iter->leftover = ret; | |
2748 | ||
bc0c38d1 | 2749 | } else { |
f9896bf3 | 2750 | print_trace_line(iter); |
a63ce5b3 SR |
2751 | ret = trace_print_seq(m, &iter->seq); |
2752 | /* | |
2753 | * If we overflow the seq_file buffer, then it will | |
2754 | * ask us for this data again at start up. | |
2755 | * Use that instead. | |
2756 | * ret is 0 if seq_file write succeeded. | |
2757 | * -1 otherwise. | |
2758 | */ | |
2759 | iter->leftover = ret; | |
bc0c38d1 SR |
2760 | } |
2761 | ||
2762 | return 0; | |
2763 | } | |
2764 | ||
88e9d34c | 2765 | static const struct seq_operations tracer_seq_ops = { |
4bf39a94 IM |
2766 | .start = s_start, |
2767 | .next = s_next, | |
2768 | .stop = s_stop, | |
2769 | .show = s_show, | |
bc0c38d1 SR |
2770 | }; |
2771 | ||
e309b41d | 2772 | static struct trace_iterator * |
debdd57f | 2773 | __tracing_open(struct inode *inode, struct file *file, bool snapshot) |
bc0c38d1 | 2774 | { |
2b6080f2 SR |
2775 | struct trace_cpu *tc = inode->i_private; |
2776 | struct trace_array *tr = tc->tr; | |
bc0c38d1 | 2777 | struct trace_iterator *iter; |
50e18b94 | 2778 | int cpu; |
bc0c38d1 | 2779 | |
85a2f9b4 SR |
2780 | if (tracing_disabled) |
2781 | return ERR_PTR(-ENODEV); | |
60a11774 | 2782 | |
50e18b94 | 2783 | iter = __seq_open_private(file, &tracer_seq_ops, sizeof(*iter)); |
85a2f9b4 SR |
2784 | if (!iter) |
2785 | return ERR_PTR(-ENOMEM); | |
bc0c38d1 | 2786 | |
6d158a81 SR |
2787 | iter->buffer_iter = kzalloc(sizeof(*iter->buffer_iter) * num_possible_cpus(), |
2788 | GFP_KERNEL); | |
93574fcc DC |
2789 | if (!iter->buffer_iter) |
2790 | goto release; | |
2791 | ||
d7350c3f FW |
2792 | /* |
2793 | * We make a copy of the current tracer to avoid concurrent | |
2794 | * changes on it while we are reading. | |
2795 | */ | |
bc0c38d1 | 2796 | mutex_lock(&trace_types_lock); |
d7350c3f | 2797 | iter->trace = kzalloc(sizeof(*iter->trace), GFP_KERNEL); |
85a2f9b4 | 2798 | if (!iter->trace) |
d7350c3f | 2799 | goto fail; |
85a2f9b4 | 2800 | |
2b6080f2 | 2801 | *iter->trace = *tr->current_trace; |
d7350c3f | 2802 | |
79f55997 | 2803 | if (!zalloc_cpumask_var(&iter->started, GFP_KERNEL)) |
b0dfa978 FW |
2804 | goto fail; |
2805 | ||
12883efb SRRH |
2806 | iter->tr = tr; |
2807 | ||
2808 | #ifdef CONFIG_TRACER_MAX_TRACE | |
2b6080f2 SR |
2809 | /* Currently only the top directory has a snapshot */ |
2810 | if (tr->current_trace->print_max || snapshot) | |
12883efb | 2811 | iter->trace_buffer = &tr->max_buffer; |
bc0c38d1 | 2812 | else |
12883efb SRRH |
2813 | #endif |
2814 | iter->trace_buffer = &tr->trace_buffer; | |
debdd57f | 2815 | iter->snapshot = snapshot; |
bc0c38d1 | 2816 | iter->pos = -1; |
d7350c3f | 2817 | mutex_init(&iter->mutex); |
2b6080f2 | 2818 | iter->cpu_file = tc->cpu; |
bc0c38d1 | 2819 | |
8bba1bf5 MM |
2820 | /* Notify the tracer early; before we stop tracing. */ |
2821 | if (iter->trace && iter->trace->open) | |
a93751ca | 2822 | iter->trace->open(iter); |
8bba1bf5 | 2823 | |
12ef7d44 | 2824 | /* Annotate start of buffers if we had overruns */ |
12883efb | 2825 | if (ring_buffer_overruns(iter->trace_buffer->buffer)) |
12ef7d44 SR |
2826 | iter->iter_flags |= TRACE_FILE_ANNOTATE; |
2827 | ||
8be0709f DS |
2828 | /* Output in nanoseconds only if we are using a clock in nanoseconds. */ |
2829 | if (trace_clocks[trace_clock_id].in_ns) | |
2830 | iter->iter_flags |= TRACE_FILE_TIME_IN_NS; | |
2831 | ||
debdd57f HT |
2832 | /* stop the trace while dumping if we are not opening "snapshot" */ |
2833 | if (!iter->snapshot) | |
2b6080f2 | 2834 | tracing_stop_tr(tr); |
2f26ebd5 | 2835 | |
ae3b5093 | 2836 | if (iter->cpu_file == RING_BUFFER_ALL_CPUS) { |
b04cc6b1 | 2837 | for_each_tracing_cpu(cpu) { |
b04cc6b1 | 2838 | iter->buffer_iter[cpu] = |
12883efb | 2839 | ring_buffer_read_prepare(iter->trace_buffer->buffer, cpu); |
72c9ddfd DM |
2840 | } |
2841 | ring_buffer_read_prepare_sync(); | |
2842 | for_each_tracing_cpu(cpu) { | |
2843 | ring_buffer_read_start(iter->buffer_iter[cpu]); | |
2f26ebd5 | 2844 | tracing_iter_reset(iter, cpu); |
b04cc6b1 FW |
2845 | } |
2846 | } else { | |
2847 | cpu = iter->cpu_file; | |
3928a8a2 | 2848 | iter->buffer_iter[cpu] = |
12883efb | 2849 | ring_buffer_read_prepare(iter->trace_buffer->buffer, cpu); |
72c9ddfd DM |
2850 | ring_buffer_read_prepare_sync(); |
2851 | ring_buffer_read_start(iter->buffer_iter[cpu]); | |
2f26ebd5 | 2852 | tracing_iter_reset(iter, cpu); |
3928a8a2 SR |
2853 | } |
2854 | ||
a695cb58 SRRH |
2855 | tr->ref++; |
2856 | ||
bc0c38d1 SR |
2857 | mutex_unlock(&trace_types_lock); |
2858 | ||
bc0c38d1 | 2859 | return iter; |
3928a8a2 | 2860 | |
d7350c3f | 2861 | fail: |
3928a8a2 | 2862 | mutex_unlock(&trace_types_lock); |
d7350c3f | 2863 | kfree(iter->trace); |
6d158a81 | 2864 | kfree(iter->buffer_iter); |
93574fcc | 2865 | release: |
50e18b94 JO |
2866 | seq_release_private(inode, file); |
2867 | return ERR_PTR(-ENOMEM); | |
bc0c38d1 SR |
2868 | } |
2869 | ||
2870 | int tracing_open_generic(struct inode *inode, struct file *filp) | |
2871 | { | |
60a11774 SR |
2872 | if (tracing_disabled) |
2873 | return -ENODEV; | |
2874 | ||
bc0c38d1 SR |
2875 | filp->private_data = inode->i_private; |
2876 | return 0; | |
2877 | } | |
2878 | ||
4fd27358 | 2879 | static int tracing_release(struct inode *inode, struct file *file) |
bc0c38d1 | 2880 | { |
907f2784 | 2881 | struct seq_file *m = file->private_data; |
4acd4d00 | 2882 | struct trace_iterator *iter; |
2b6080f2 | 2883 | struct trace_array *tr; |
3928a8a2 | 2884 | int cpu; |
bc0c38d1 | 2885 | |
4acd4d00 SR |
2886 | if (!(file->f_mode & FMODE_READ)) |
2887 | return 0; | |
2888 | ||
2889 | iter = m->private; | |
12883efb | 2890 | tr = iter->tr; |
4acd4d00 | 2891 | |
bc0c38d1 | 2892 | mutex_lock(&trace_types_lock); |
a695cb58 SRRH |
2893 | |
2894 | WARN_ON(!tr->ref); | |
2895 | tr->ref--; | |
2896 | ||
3928a8a2 SR |
2897 | for_each_tracing_cpu(cpu) { |
2898 | if (iter->buffer_iter[cpu]) | |
2899 | ring_buffer_read_finish(iter->buffer_iter[cpu]); | |
2900 | } | |
2901 | ||
bc0c38d1 SR |
2902 | if (iter->trace && iter->trace->close) |
2903 | iter->trace->close(iter); | |
2904 | ||
debdd57f HT |
2905 | if (!iter->snapshot) |
2906 | /* reenable tracing if it was previously enabled */ | |
2b6080f2 | 2907 | tracing_start_tr(tr); |
bc0c38d1 SR |
2908 | mutex_unlock(&trace_types_lock); |
2909 | ||
d7350c3f | 2910 | mutex_destroy(&iter->mutex); |
b0dfa978 | 2911 | free_cpumask_var(iter->started); |
d7350c3f | 2912 | kfree(iter->trace); |
6d158a81 | 2913 | kfree(iter->buffer_iter); |
50e18b94 | 2914 | seq_release_private(inode, file); |
bc0c38d1 SR |
2915 | return 0; |
2916 | } | |
2917 | ||
2918 | static int tracing_open(struct inode *inode, struct file *file) | |
2919 | { | |
85a2f9b4 SR |
2920 | struct trace_iterator *iter; |
2921 | int ret = 0; | |
bc0c38d1 | 2922 | |
4acd4d00 SR |
2923 | /* If this file was open for write, then erase contents */ |
2924 | if ((file->f_mode & FMODE_WRITE) && | |
8650ae32 | 2925 | (file->f_flags & O_TRUNC)) { |
2b6080f2 SR |
2926 | struct trace_cpu *tc = inode->i_private; |
2927 | struct trace_array *tr = tc->tr; | |
bc0c38d1 | 2928 | |
2b6080f2 | 2929 | if (tc->cpu == RING_BUFFER_ALL_CPUS) |
12883efb | 2930 | tracing_reset_online_cpus(&tr->trace_buffer); |
4acd4d00 | 2931 | else |
12883efb | 2932 | tracing_reset(&tr->trace_buffer, tc->cpu); |
4acd4d00 | 2933 | } |
bc0c38d1 | 2934 | |
4acd4d00 | 2935 | if (file->f_mode & FMODE_READ) { |
debdd57f | 2936 | iter = __tracing_open(inode, file, false); |
4acd4d00 SR |
2937 | if (IS_ERR(iter)) |
2938 | ret = PTR_ERR(iter); | |
2939 | else if (trace_flags & TRACE_ITER_LATENCY_FMT) | |
2940 | iter->iter_flags |= TRACE_FILE_LAT_FMT; | |
2941 | } | |
bc0c38d1 SR |
2942 | return ret; |
2943 | } | |
2944 | ||
e309b41d | 2945 | static void * |
bc0c38d1 SR |
2946 | t_next(struct seq_file *m, void *v, loff_t *pos) |
2947 | { | |
f129e965 | 2948 | struct tracer *t = v; |
bc0c38d1 SR |
2949 | |
2950 | (*pos)++; | |
2951 | ||
2952 | if (t) | |
2953 | t = t->next; | |
2954 | ||
bc0c38d1 SR |
2955 | return t; |
2956 | } | |
2957 | ||
2958 | static void *t_start(struct seq_file *m, loff_t *pos) | |
2959 | { | |
f129e965 | 2960 | struct tracer *t; |
bc0c38d1 SR |
2961 | loff_t l = 0; |
2962 | ||
2963 | mutex_lock(&trace_types_lock); | |
f129e965 | 2964 | for (t = trace_types; t && l < *pos; t = t_next(m, t, &l)) |
bc0c38d1 SR |
2965 | ; |
2966 | ||
2967 | return t; | |
2968 | } | |
2969 | ||
2970 | static void t_stop(struct seq_file *m, void *p) | |
2971 | { | |
2972 | mutex_unlock(&trace_types_lock); | |
2973 | } | |
2974 | ||
2975 | static int t_show(struct seq_file *m, void *v) | |
2976 | { | |
2977 | struct tracer *t = v; | |
2978 | ||
2979 | if (!t) | |
2980 | return 0; | |
2981 | ||
2982 | seq_printf(m, "%s", t->name); | |
2983 | if (t->next) | |
2984 | seq_putc(m, ' '); | |
2985 | else | |
2986 | seq_putc(m, '\n'); | |
2987 | ||
2988 | return 0; | |
2989 | } | |
2990 | ||
88e9d34c | 2991 | static const struct seq_operations show_traces_seq_ops = { |
4bf39a94 IM |
2992 | .start = t_start, |
2993 | .next = t_next, | |
2994 | .stop = t_stop, | |
2995 | .show = t_show, | |
bc0c38d1 SR |
2996 | }; |
2997 | ||
2998 | static int show_traces_open(struct inode *inode, struct file *file) | |
2999 | { | |
60a11774 SR |
3000 | if (tracing_disabled) |
3001 | return -ENODEV; | |
3002 | ||
f129e965 | 3003 | return seq_open(file, &show_traces_seq_ops); |
bc0c38d1 SR |
3004 | } |
3005 | ||
4acd4d00 SR |
3006 | static ssize_t |
3007 | tracing_write_stub(struct file *filp, const char __user *ubuf, | |
3008 | size_t count, loff_t *ppos) | |
3009 | { | |
3010 | return count; | |
3011 | } | |
3012 | ||
364829b1 SP |
3013 | static loff_t tracing_seek(struct file *file, loff_t offset, int origin) |
3014 | { | |
3015 | if (file->f_mode & FMODE_READ) | |
3016 | return seq_lseek(file, offset, origin); | |
3017 | else | |
3018 | return 0; | |
3019 | } | |
3020 | ||
5e2336a0 | 3021 | static const struct file_operations tracing_fops = { |
4bf39a94 IM |
3022 | .open = tracing_open, |
3023 | .read = seq_read, | |
4acd4d00 | 3024 | .write = tracing_write_stub, |
364829b1 | 3025 | .llseek = tracing_seek, |
4bf39a94 | 3026 | .release = tracing_release, |
bc0c38d1 SR |
3027 | }; |
3028 | ||
5e2336a0 | 3029 | static const struct file_operations show_traces_fops = { |
c7078de1 IM |
3030 | .open = show_traces_open, |
3031 | .read = seq_read, | |
3032 | .release = seq_release, | |
b444786f | 3033 | .llseek = seq_lseek, |
c7078de1 IM |
3034 | }; |
3035 | ||
36dfe925 IM |
3036 | /* |
3037 | * Only trace on a CPU if the bitmask is set: | |
3038 | */ | |
9e01c1b7 | 3039 | static cpumask_var_t tracing_cpumask; |
36dfe925 IM |
3040 | |
3041 | /* | |
3042 | * The tracer itself will not take this lock, but still we want | |
3043 | * to provide a consistent cpumask to user-space: | |
3044 | */ | |
3045 | static DEFINE_MUTEX(tracing_cpumask_update_lock); | |
3046 | ||
3047 | /* | |
3048 | * Temporary storage for the character representation of the | |
3049 | * CPU bitmask (and one more byte for the newline): | |
3050 | */ | |
3051 | static char mask_str[NR_CPUS + 1]; | |
3052 | ||
c7078de1 IM |
3053 | static ssize_t |
3054 | tracing_cpumask_read(struct file *filp, char __user *ubuf, | |
3055 | size_t count, loff_t *ppos) | |
3056 | { | |
36dfe925 | 3057 | int len; |
c7078de1 IM |
3058 | |
3059 | mutex_lock(&tracing_cpumask_update_lock); | |
36dfe925 | 3060 | |
9e01c1b7 | 3061 | len = cpumask_scnprintf(mask_str, count, tracing_cpumask); |
36dfe925 IM |
3062 | if (count - len < 2) { |
3063 | count = -EINVAL; | |
3064 | goto out_err; | |
3065 | } | |
3066 | len += sprintf(mask_str + len, "\n"); | |
3067 | count = simple_read_from_buffer(ubuf, count, ppos, mask_str, NR_CPUS+1); | |
3068 | ||
3069 | out_err: | |
c7078de1 IM |
3070 | mutex_unlock(&tracing_cpumask_update_lock); |
3071 | ||
3072 | return count; | |
3073 | } | |
3074 | ||
3075 | static ssize_t | |
3076 | tracing_cpumask_write(struct file *filp, const char __user *ubuf, | |
3077 | size_t count, loff_t *ppos) | |
3078 | { | |
2b6080f2 | 3079 | struct trace_array *tr = filp->private_data; |
9e01c1b7 | 3080 | cpumask_var_t tracing_cpumask_new; |
2b6080f2 | 3081 | int err, cpu; |
9e01c1b7 RR |
3082 | |
3083 | if (!alloc_cpumask_var(&tracing_cpumask_new, GFP_KERNEL)) | |
3084 | return -ENOMEM; | |
c7078de1 | 3085 | |
9e01c1b7 | 3086 | err = cpumask_parse_user(ubuf, count, tracing_cpumask_new); |
c7078de1 | 3087 | if (err) |
36dfe925 IM |
3088 | goto err_unlock; |
3089 | ||
215368e8 LZ |
3090 | mutex_lock(&tracing_cpumask_update_lock); |
3091 | ||
a5e25883 | 3092 | local_irq_disable(); |
0199c4e6 | 3093 | arch_spin_lock(&ftrace_max_lock); |
ab46428c | 3094 | for_each_tracing_cpu(cpu) { |
36dfe925 IM |
3095 | /* |
3096 | * Increase/decrease the disabled counter if we are | |
3097 | * about to flip a bit in the cpumask: | |
3098 | */ | |
9e01c1b7 RR |
3099 | if (cpumask_test_cpu(cpu, tracing_cpumask) && |
3100 | !cpumask_test_cpu(cpu, tracing_cpumask_new)) { | |
12883efb SRRH |
3101 | atomic_inc(&per_cpu_ptr(tr->trace_buffer.data, cpu)->disabled); |
3102 | ring_buffer_record_disable_cpu(tr->trace_buffer.buffer, cpu); | |
36dfe925 | 3103 | } |
9e01c1b7 RR |
3104 | if (!cpumask_test_cpu(cpu, tracing_cpumask) && |
3105 | cpumask_test_cpu(cpu, tracing_cpumask_new)) { | |
12883efb SRRH |
3106 | atomic_dec(&per_cpu_ptr(tr->trace_buffer.data, cpu)->disabled); |
3107 | ring_buffer_record_enable_cpu(tr->trace_buffer.buffer, cpu); | |
36dfe925 IM |
3108 | } |
3109 | } | |
0199c4e6 | 3110 | arch_spin_unlock(&ftrace_max_lock); |
a5e25883 | 3111 | local_irq_enable(); |
36dfe925 | 3112 | |
9e01c1b7 | 3113 | cpumask_copy(tracing_cpumask, tracing_cpumask_new); |
36dfe925 IM |
3114 | |
3115 | mutex_unlock(&tracing_cpumask_update_lock); | |
9e01c1b7 | 3116 | free_cpumask_var(tracing_cpumask_new); |
c7078de1 IM |
3117 | |
3118 | return count; | |
36dfe925 IM |
3119 | |
3120 | err_unlock: | |
215368e8 | 3121 | free_cpumask_var(tracing_cpumask_new); |
36dfe925 IM |
3122 | |
3123 | return err; | |
c7078de1 IM |
3124 | } |
3125 | ||
5e2336a0 | 3126 | static const struct file_operations tracing_cpumask_fops = { |
c7078de1 IM |
3127 | .open = tracing_open_generic, |
3128 | .read = tracing_cpumask_read, | |
3129 | .write = tracing_cpumask_write, | |
b444786f | 3130 | .llseek = generic_file_llseek, |
bc0c38d1 SR |
3131 | }; |
3132 | ||
fdb372ed | 3133 | static int tracing_trace_options_show(struct seq_file *m, void *v) |
bc0c38d1 | 3134 | { |
d8e83d26 | 3135 | struct tracer_opt *trace_opts; |
2b6080f2 | 3136 | struct trace_array *tr = m->private; |
d8e83d26 | 3137 | u32 tracer_flags; |
d8e83d26 | 3138 | int i; |
adf9f195 | 3139 | |
d8e83d26 | 3140 | mutex_lock(&trace_types_lock); |
2b6080f2 SR |
3141 | tracer_flags = tr->current_trace->flags->val; |
3142 | trace_opts = tr->current_trace->flags->opts; | |
d8e83d26 | 3143 | |
bc0c38d1 SR |
3144 | for (i = 0; trace_options[i]; i++) { |
3145 | if (trace_flags & (1 << i)) | |
fdb372ed | 3146 | seq_printf(m, "%s\n", trace_options[i]); |
bc0c38d1 | 3147 | else |
fdb372ed | 3148 | seq_printf(m, "no%s\n", trace_options[i]); |
bc0c38d1 SR |
3149 | } |
3150 | ||
adf9f195 FW |
3151 | for (i = 0; trace_opts[i].name; i++) { |
3152 | if (tracer_flags & trace_opts[i].bit) | |
fdb372ed | 3153 | seq_printf(m, "%s\n", trace_opts[i].name); |
adf9f195 | 3154 | else |
fdb372ed | 3155 | seq_printf(m, "no%s\n", trace_opts[i].name); |
adf9f195 | 3156 | } |
d8e83d26 | 3157 | mutex_unlock(&trace_types_lock); |
adf9f195 | 3158 | |
fdb372ed | 3159 | return 0; |
bc0c38d1 | 3160 | } |
bc0c38d1 | 3161 | |
8d18eaaf LZ |
3162 | static int __set_tracer_option(struct tracer *trace, |
3163 | struct tracer_flags *tracer_flags, | |
3164 | struct tracer_opt *opts, int neg) | |
3165 | { | |
3166 | int ret; | |
bc0c38d1 | 3167 | |
8d18eaaf LZ |
3168 | ret = trace->set_flag(tracer_flags->val, opts->bit, !neg); |
3169 | if (ret) | |
3170 | return ret; | |
3171 | ||
3172 | if (neg) | |
3173 | tracer_flags->val &= ~opts->bit; | |
3174 | else | |
3175 | tracer_flags->val |= opts->bit; | |
3176 | return 0; | |
bc0c38d1 SR |
3177 | } |
3178 | ||
adf9f195 FW |
3179 | /* Try to assign a tracer specific option */ |
3180 | static int set_tracer_option(struct tracer *trace, char *cmp, int neg) | |
3181 | { | |
7770841e | 3182 | struct tracer_flags *tracer_flags = trace->flags; |
adf9f195 | 3183 | struct tracer_opt *opts = NULL; |
8d18eaaf | 3184 | int i; |
adf9f195 | 3185 | |
7770841e Z |
3186 | for (i = 0; tracer_flags->opts[i].name; i++) { |
3187 | opts = &tracer_flags->opts[i]; | |
adf9f195 | 3188 | |
8d18eaaf LZ |
3189 | if (strcmp(cmp, opts->name) == 0) |
3190 | return __set_tracer_option(trace, trace->flags, | |
3191 | opts, neg); | |
adf9f195 | 3192 | } |
adf9f195 | 3193 | |
8d18eaaf | 3194 | return -EINVAL; |
adf9f195 FW |
3195 | } |
3196 | ||
613f04a0 SRRH |
3197 | /* Some tracers require overwrite to stay enabled */ |
3198 | int trace_keep_overwrite(struct tracer *tracer, u32 mask, int set) | |
3199 | { | |
3200 | if (tracer->enabled && (mask & TRACE_ITER_OVERWRITE) && !set) | |
3201 | return -1; | |
3202 | ||
3203 | return 0; | |
3204 | } | |
3205 | ||
2b6080f2 | 3206 | int set_tracer_flag(struct trace_array *tr, unsigned int mask, int enabled) |
af4617bd SR |
3207 | { |
3208 | /* do nothing if flag is already set */ | |
3209 | if (!!(trace_flags & mask) == !!enabled) | |
613f04a0 SRRH |
3210 | return 0; |
3211 | ||
3212 | /* Give the tracer a chance to approve the change */ | |
2b6080f2 SR |
3213 | if (tr->current_trace->flag_changed) |
3214 | if (tr->current_trace->flag_changed(tr->current_trace, mask, !!enabled)) | |
613f04a0 | 3215 | return -EINVAL; |
af4617bd SR |
3216 | |
3217 | if (enabled) | |
3218 | trace_flags |= mask; | |
3219 | else | |
3220 | trace_flags &= ~mask; | |
e870e9a1 LZ |
3221 | |
3222 | if (mask == TRACE_ITER_RECORD_CMD) | |
3223 | trace_event_enable_cmd_record(enabled); | |
750912fa | 3224 | |
80902822 | 3225 | if (mask == TRACE_ITER_OVERWRITE) { |
12883efb | 3226 | ring_buffer_change_overwrite(tr->trace_buffer.buffer, enabled); |
80902822 | 3227 | #ifdef CONFIG_TRACER_MAX_TRACE |
12883efb | 3228 | ring_buffer_change_overwrite(tr->max_buffer.buffer, enabled); |
80902822 SRRH |
3229 | #endif |
3230 | } | |
81698831 SR |
3231 | |
3232 | if (mask == TRACE_ITER_PRINTK) | |
3233 | trace_printk_start_stop_comm(enabled); | |
613f04a0 SRRH |
3234 | |
3235 | return 0; | |
af4617bd SR |
3236 | } |
3237 | ||
2b6080f2 | 3238 | static int trace_set_options(struct trace_array *tr, char *option) |
bc0c38d1 | 3239 | { |
8d18eaaf | 3240 | char *cmp; |
bc0c38d1 | 3241 | int neg = 0; |
613f04a0 | 3242 | int ret = -ENODEV; |
bc0c38d1 SR |
3243 | int i; |
3244 | ||
7bcfaf54 | 3245 | cmp = strstrip(option); |
bc0c38d1 | 3246 | |
8d18eaaf | 3247 | if (strncmp(cmp, "no", 2) == 0) { |
bc0c38d1 SR |
3248 | neg = 1; |
3249 | cmp += 2; | |
3250 | } | |
3251 | ||
69d34da2 SRRH |
3252 | mutex_lock(&trace_types_lock); |
3253 | ||
bc0c38d1 | 3254 | for (i = 0; trace_options[i]; i++) { |
8d18eaaf | 3255 | if (strcmp(cmp, trace_options[i]) == 0) { |
2b6080f2 | 3256 | ret = set_tracer_flag(tr, 1 << i, !neg); |
bc0c38d1 SR |
3257 | break; |
3258 | } | |
3259 | } | |
adf9f195 FW |
3260 | |
3261 | /* If no option could be set, test the specific tracer options */ | |
69d34da2 | 3262 | if (!trace_options[i]) |
2b6080f2 | 3263 | ret = set_tracer_option(tr->current_trace, cmp, neg); |
69d34da2 SRRH |
3264 | |
3265 | mutex_unlock(&trace_types_lock); | |
bc0c38d1 | 3266 | |
7bcfaf54 SR |
3267 | return ret; |
3268 | } | |
3269 | ||
3270 | static ssize_t | |
3271 | tracing_trace_options_write(struct file *filp, const char __user *ubuf, | |
3272 | size_t cnt, loff_t *ppos) | |
3273 | { | |
2b6080f2 SR |
3274 | struct seq_file *m = filp->private_data; |
3275 | struct trace_array *tr = m->private; | |
7bcfaf54 | 3276 | char buf[64]; |
613f04a0 | 3277 | int ret; |
7bcfaf54 SR |
3278 | |
3279 | if (cnt >= sizeof(buf)) | |
3280 | return -EINVAL; | |
3281 | ||
3282 | if (copy_from_user(&buf, ubuf, cnt)) | |
3283 | return -EFAULT; | |
3284 | ||
a8dd2176 SR |
3285 | buf[cnt] = 0; |
3286 | ||
2b6080f2 | 3287 | ret = trace_set_options(tr, buf); |
613f04a0 SRRH |
3288 | if (ret < 0) |
3289 | return ret; | |
7bcfaf54 | 3290 | |
cf8517cf | 3291 | *ppos += cnt; |
bc0c38d1 SR |
3292 | |
3293 | return cnt; | |
3294 | } | |
3295 | ||
fdb372ed LZ |
3296 | static int tracing_trace_options_open(struct inode *inode, struct file *file) |
3297 | { | |
3298 | if (tracing_disabled) | |
3299 | return -ENODEV; | |
2b6080f2 SR |
3300 | |
3301 | return single_open(file, tracing_trace_options_show, inode->i_private); | |
fdb372ed LZ |
3302 | } |
3303 | ||
5e2336a0 | 3304 | static const struct file_operations tracing_iter_fops = { |
fdb372ed LZ |
3305 | .open = tracing_trace_options_open, |
3306 | .read = seq_read, | |
3307 | .llseek = seq_lseek, | |
3308 | .release = single_release, | |
ee6bce52 | 3309 | .write = tracing_trace_options_write, |
bc0c38d1 SR |
3310 | }; |
3311 | ||
7bd2f24c IM |
3312 | static const char readme_msg[] = |
3313 | "tracing mini-HOWTO:\n\n" | |
22f45649 SRRH |
3314 | "# echo 0 > tracing_on : quick way to disable tracing\n" |
3315 | "# echo 1 > tracing_on : quick way to re-enable tracing\n\n" | |
3316 | " Important files:\n" | |
3317 | " trace\t\t\t- The static contents of the buffer\n" | |
3318 | "\t\t\t To clear the buffer write into this file: echo > trace\n" | |
3319 | " trace_pipe\t\t- A consuming read to see the contents of the buffer\n" | |
3320 | " current_tracer\t- function and latency tracers\n" | |
3321 | " available_tracers\t- list of configured tracers for current_tracer\n" | |
3322 | " buffer_size_kb\t- view and modify size of per cpu buffer\n" | |
3323 | " buffer_total_size_kb - view total size of all cpu buffers\n\n" | |
3324 | " trace_clock\t\t-change the clock used to order events\n" | |
3325 | " local: Per cpu clock but may not be synced across CPUs\n" | |
3326 | " global: Synced across CPUs but slows tracing down.\n" | |
3327 | " counter: Not a clock, but just an increment\n" | |
3328 | " uptime: Jiffy counter from time of boot\n" | |
3329 | " perf: Same clock that perf events use\n" | |
3330 | #ifdef CONFIG_X86_64 | |
3331 | " x86-tsc: TSC cycle counter\n" | |
3332 | #endif | |
3333 | "\n trace_marker\t\t- Writes into this file writes into the kernel buffer\n" | |
3334 | " tracing_cpumask\t- Limit which CPUs to trace\n" | |
3335 | " instances\t\t- Make sub-buffers with: mkdir instances/foo\n" | |
3336 | "\t\t\t Remove sub-buffer with rmdir\n" | |
3337 | " trace_options\t\t- Set format or modify how tracing happens\n" | |
3338 | "\t\t\t Disable an option by adding a suffix 'no' to the option name\n" | |
3339 | #ifdef CONFIG_DYNAMIC_FTRACE | |
3340 | "\n available_filter_functions - list of functions that can be filtered on\n" | |
3341 | " set_ftrace_filter\t- echo function name in here to only trace these functions\n" | |
3342 | " accepts: func_full_name, *func_end, func_begin*, *func_middle*\n" | |
3343 | " modules: Can select a group via module\n" | |
3344 | " Format: :mod:<module-name>\n" | |
3345 | " example: echo :mod:ext3 > set_ftrace_filter\n" | |
3346 | " triggers: a command to perform when function is hit\n" | |
3347 | " Format: <function>:<trigger>[:count]\n" | |
3348 | " trigger: traceon, traceoff\n" | |
3349 | " enable_event:<system>:<event>\n" | |
3350 | " disable_event:<system>:<event>\n" | |
3351 | #ifdef CONFIG_STACKTRACE | |
3352 | " stacktrace\n" | |
3353 | #endif | |
3354 | #ifdef CONFIG_TRACER_SNAPSHOT | |
3355 | " snapshot\n" | |
3356 | #endif | |
3357 | " example: echo do_fault:traceoff > set_ftrace_filter\n" | |
3358 | " echo do_trap:traceoff:3 > set_ftrace_filter\n" | |
3359 | " The first one will disable tracing every time do_fault is hit\n" | |
3360 | " The second will disable tracing at most 3 times when do_trap is hit\n" | |
3361 | " The first time do trap is hit and it disables tracing, the counter\n" | |
3362 | " will decrement to 2. If tracing is already disabled, the counter\n" | |
3363 | " will not decrement. It only decrements when the trigger did work\n" | |
3364 | " To remove trigger without count:\n" | |
3365 | " echo '!<function>:<trigger> > set_ftrace_filter\n" | |
3366 | " To remove trigger with a count:\n" | |
3367 | " echo '!<function>:<trigger>:0 > set_ftrace_filter\n" | |
3368 | " set_ftrace_notrace\t- echo function name in here to never trace.\n" | |
3369 | " accepts: func_full_name, *func_end, func_begin*, *func_middle*\n" | |
3370 | " modules: Can select a group via module command :mod:\n" | |
3371 | " Does not accept triggers\n" | |
3372 | #endif /* CONFIG_DYNAMIC_FTRACE */ | |
3373 | #ifdef CONFIG_FUNCTION_TRACER | |
3374 | " set_ftrace_pid\t- Write pid(s) to only function trace those pids (function)\n" | |
3375 | #endif | |
3376 | #ifdef CONFIG_FUNCTION_GRAPH_TRACER | |
3377 | " set_graph_function\t- Trace the nested calls of a function (function_graph)\n" | |
3378 | " max_graph_depth\t- Trace a limited depth of nested calls (0 is unlimited)\n" | |
3379 | #endif | |
3380 | #ifdef CONFIG_TRACER_SNAPSHOT | |
3381 | "\n snapshot\t\t- Like 'trace' but shows the content of the static snapshot buffer\n" | |
3382 | "\t\t\t Read the contents for more information\n" | |
3383 | #endif | |
3384 | #ifdef CONFIG_STACKTRACE | |
3385 | " stack_trace\t\t- Shows the max stack trace when active\n" | |
3386 | " stack_max_size\t- Shows current max stack size that was traced\n" | |
3387 | "\t\t\t Write into this file to reset the max size (trigger a new trace)\n" | |
3388 | #ifdef CONFIG_DYNAMIC_FTRACE | |
3389 | " stack_trace_filter\t- Like set_ftrace_filter but limits what stack_trace traces\n" | |
3390 | #endif | |
3391 | #endif /* CONFIG_STACKTRACE */ | |
7bd2f24c IM |
3392 | ; |
3393 | ||
3394 | static ssize_t | |
3395 | tracing_readme_read(struct file *filp, char __user *ubuf, | |
3396 | size_t cnt, loff_t *ppos) | |
3397 | { | |
3398 | return simple_read_from_buffer(ubuf, cnt, ppos, | |
3399 | readme_msg, strlen(readme_msg)); | |
3400 | } | |
3401 | ||
5e2336a0 | 3402 | static const struct file_operations tracing_readme_fops = { |
c7078de1 IM |
3403 | .open = tracing_open_generic, |
3404 | .read = tracing_readme_read, | |
b444786f | 3405 | .llseek = generic_file_llseek, |
7bd2f24c IM |
3406 | }; |
3407 | ||
69abe6a5 AP |
3408 | static ssize_t |
3409 | tracing_saved_cmdlines_read(struct file *file, char __user *ubuf, | |
3410 | size_t cnt, loff_t *ppos) | |
3411 | { | |
3412 | char *buf_comm; | |
3413 | char *file_buf; | |
3414 | char *buf; | |
3415 | int len = 0; | |
3416 | int pid; | |
3417 | int i; | |
3418 | ||
3419 | file_buf = kmalloc(SAVED_CMDLINES*(16+TASK_COMM_LEN), GFP_KERNEL); | |
3420 | if (!file_buf) | |
3421 | return -ENOMEM; | |
3422 | ||
3423 | buf_comm = kmalloc(TASK_COMM_LEN, GFP_KERNEL); | |
3424 | if (!buf_comm) { | |
3425 | kfree(file_buf); | |
3426 | return -ENOMEM; | |
3427 | } | |
3428 | ||
3429 | buf = file_buf; | |
3430 | ||
3431 | for (i = 0; i < SAVED_CMDLINES; i++) { | |
3432 | int r; | |
3433 | ||
3434 | pid = map_cmdline_to_pid[i]; | |
3435 | if (pid == -1 || pid == NO_CMDLINE_MAP) | |
3436 | continue; | |
3437 | ||
3438 | trace_find_cmdline(pid, buf_comm); | |
3439 | r = sprintf(buf, "%d %s\n", pid, buf_comm); | |
3440 | buf += r; | |
3441 | len += r; | |
3442 | } | |
3443 | ||
3444 | len = simple_read_from_buffer(ubuf, cnt, ppos, | |
3445 | file_buf, len); | |
3446 | ||
3447 | kfree(file_buf); | |
3448 | kfree(buf_comm); | |
3449 | ||
3450 | return len; | |
3451 | } | |
3452 | ||
3453 | static const struct file_operations tracing_saved_cmdlines_fops = { | |
3454 | .open = tracing_open_generic, | |
3455 | .read = tracing_saved_cmdlines_read, | |
b444786f | 3456 | .llseek = generic_file_llseek, |
69abe6a5 AP |
3457 | }; |
3458 | ||
bc0c38d1 SR |
3459 | static ssize_t |
3460 | tracing_set_trace_read(struct file *filp, char __user *ubuf, | |
3461 | size_t cnt, loff_t *ppos) | |
3462 | { | |
2b6080f2 | 3463 | struct trace_array *tr = filp->private_data; |
ee6c2c1b | 3464 | char buf[MAX_TRACER_SIZE+2]; |
bc0c38d1 SR |
3465 | int r; |
3466 | ||
3467 | mutex_lock(&trace_types_lock); | |
2b6080f2 | 3468 | r = sprintf(buf, "%s\n", tr->current_trace->name); |
bc0c38d1 SR |
3469 | mutex_unlock(&trace_types_lock); |
3470 | ||
4bf39a94 | 3471 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, r); |
bc0c38d1 SR |
3472 | } |
3473 | ||
b6f11df2 ACM |
3474 | int tracer_init(struct tracer *t, struct trace_array *tr) |
3475 | { | |
12883efb | 3476 | tracing_reset_online_cpus(&tr->trace_buffer); |
b6f11df2 ACM |
3477 | return t->init(tr); |
3478 | } | |
3479 | ||
12883efb | 3480 | static void set_buffer_entries(struct trace_buffer *buf, unsigned long val) |
438ced17 VN |
3481 | { |
3482 | int cpu; | |
737223fb | 3483 | |
438ced17 | 3484 | for_each_tracing_cpu(cpu) |
12883efb | 3485 | per_cpu_ptr(buf->data, cpu)->entries = val; |
438ced17 VN |
3486 | } |
3487 | ||
12883efb | 3488 | #ifdef CONFIG_TRACER_MAX_TRACE |
d60da506 | 3489 | /* resize @tr's buffer to the size of @size_tr's entries */ |
12883efb SRRH |
3490 | static int resize_buffer_duplicate_size(struct trace_buffer *trace_buf, |
3491 | struct trace_buffer *size_buf, int cpu_id) | |
d60da506 HT |
3492 | { |
3493 | int cpu, ret = 0; | |
3494 | ||
3495 | if (cpu_id == RING_BUFFER_ALL_CPUS) { | |
3496 | for_each_tracing_cpu(cpu) { | |
12883efb SRRH |
3497 | ret = ring_buffer_resize(trace_buf->buffer, |
3498 | per_cpu_ptr(size_buf->data, cpu)->entries, cpu); | |
d60da506 HT |
3499 | if (ret < 0) |
3500 | break; | |
12883efb SRRH |
3501 | per_cpu_ptr(trace_buf->data, cpu)->entries = |
3502 | per_cpu_ptr(size_buf->data, cpu)->entries; | |
d60da506 HT |
3503 | } |
3504 | } else { | |
12883efb SRRH |
3505 | ret = ring_buffer_resize(trace_buf->buffer, |
3506 | per_cpu_ptr(size_buf->data, cpu_id)->entries, cpu_id); | |
d60da506 | 3507 | if (ret == 0) |
12883efb SRRH |
3508 | per_cpu_ptr(trace_buf->data, cpu_id)->entries = |
3509 | per_cpu_ptr(size_buf->data, cpu_id)->entries; | |
d60da506 HT |
3510 | } |
3511 | ||
3512 | return ret; | |
3513 | } | |
12883efb | 3514 | #endif /* CONFIG_TRACER_MAX_TRACE */ |
d60da506 | 3515 | |
2b6080f2 SR |
3516 | static int __tracing_resize_ring_buffer(struct trace_array *tr, |
3517 | unsigned long size, int cpu) | |
73c5162a SR |
3518 | { |
3519 | int ret; | |
3520 | ||
3521 | /* | |
3522 | * If kernel or user changes the size of the ring buffer | |
a123c52b SR |
3523 | * we use the size that was given, and we can forget about |
3524 | * expanding it later. | |
73c5162a | 3525 | */ |
55034cd6 | 3526 | ring_buffer_expanded = true; |
73c5162a | 3527 | |
b382ede6 | 3528 | /* May be called before buffers are initialized */ |
12883efb | 3529 | if (!tr->trace_buffer.buffer) |
b382ede6 SR |
3530 | return 0; |
3531 | ||
12883efb | 3532 | ret = ring_buffer_resize(tr->trace_buffer.buffer, size, cpu); |
73c5162a SR |
3533 | if (ret < 0) |
3534 | return ret; | |
3535 | ||
12883efb | 3536 | #ifdef CONFIG_TRACER_MAX_TRACE |
2b6080f2 SR |
3537 | if (!(tr->flags & TRACE_ARRAY_FL_GLOBAL) || |
3538 | !tr->current_trace->use_max_tr) | |
ef710e10 KM |
3539 | goto out; |
3540 | ||
12883efb | 3541 | ret = ring_buffer_resize(tr->max_buffer.buffer, size, cpu); |
73c5162a | 3542 | if (ret < 0) { |
12883efb SRRH |
3543 | int r = resize_buffer_duplicate_size(&tr->trace_buffer, |
3544 | &tr->trace_buffer, cpu); | |
73c5162a | 3545 | if (r < 0) { |
a123c52b SR |
3546 | /* |
3547 | * AARGH! We are left with different | |
3548 | * size max buffer!!!! | |
3549 | * The max buffer is our "snapshot" buffer. | |
3550 | * When a tracer needs a snapshot (one of the | |
3551 | * latency tracers), it swaps the max buffer | |
3552 | * with the saved snap shot. We succeeded to | |
3553 | * update the size of the main buffer, but failed to | |
3554 | * update the size of the max buffer. But when we tried | |
3555 | * to reset the main buffer to the original size, we | |
3556 | * failed there too. This is very unlikely to | |
3557 | * happen, but if it does, warn and kill all | |
3558 | * tracing. | |
3559 | */ | |
73c5162a SR |
3560 | WARN_ON(1); |
3561 | tracing_disabled = 1; | |
3562 | } | |
3563 | return ret; | |
3564 | } | |
3565 | ||
438ced17 | 3566 | if (cpu == RING_BUFFER_ALL_CPUS) |
12883efb | 3567 | set_buffer_entries(&tr->max_buffer, size); |
438ced17 | 3568 | else |
12883efb | 3569 | per_cpu_ptr(tr->max_buffer.data, cpu)->entries = size; |
438ced17 | 3570 | |
ef710e10 | 3571 | out: |
12883efb SRRH |
3572 | #endif /* CONFIG_TRACER_MAX_TRACE */ |
3573 | ||
438ced17 | 3574 | if (cpu == RING_BUFFER_ALL_CPUS) |
12883efb | 3575 | set_buffer_entries(&tr->trace_buffer, size); |
438ced17 | 3576 | else |
12883efb | 3577 | per_cpu_ptr(tr->trace_buffer.data, cpu)->entries = size; |
73c5162a SR |
3578 | |
3579 | return ret; | |
3580 | } | |
3581 | ||
2b6080f2 SR |
3582 | static ssize_t tracing_resize_ring_buffer(struct trace_array *tr, |
3583 | unsigned long size, int cpu_id) | |
4f271a2a | 3584 | { |
83f40318 | 3585 | int ret = size; |
4f271a2a VN |
3586 | |
3587 | mutex_lock(&trace_types_lock); | |
3588 | ||
438ced17 VN |
3589 | if (cpu_id != RING_BUFFER_ALL_CPUS) { |
3590 | /* make sure, this cpu is enabled in the mask */ | |
3591 | if (!cpumask_test_cpu(cpu_id, tracing_buffer_mask)) { | |
3592 | ret = -EINVAL; | |
3593 | goto out; | |
3594 | } | |
3595 | } | |
4f271a2a | 3596 | |
2b6080f2 | 3597 | ret = __tracing_resize_ring_buffer(tr, size, cpu_id); |
4f271a2a VN |
3598 | if (ret < 0) |
3599 | ret = -ENOMEM; | |
3600 | ||
438ced17 | 3601 | out: |
4f271a2a VN |
3602 | mutex_unlock(&trace_types_lock); |
3603 | ||
3604 | return ret; | |
3605 | } | |
3606 | ||
ef710e10 | 3607 | |
1852fcce SR |
3608 | /** |
3609 | * tracing_update_buffers - used by tracing facility to expand ring buffers | |
3610 | * | |
3611 | * To save on memory when the tracing is never used on a system with it | |
3612 | * configured in. The ring buffers are set to a minimum size. But once | |
3613 | * a user starts to use the tracing facility, then they need to grow | |
3614 | * to their default size. | |
3615 | * | |
3616 | * This function is to be called when a tracer is about to be used. | |
3617 | */ | |
3618 | int tracing_update_buffers(void) | |
3619 | { | |
3620 | int ret = 0; | |
3621 | ||
1027fcb2 | 3622 | mutex_lock(&trace_types_lock); |
1852fcce | 3623 | if (!ring_buffer_expanded) |
2b6080f2 | 3624 | ret = __tracing_resize_ring_buffer(&global_trace, trace_buf_size, |
438ced17 | 3625 | RING_BUFFER_ALL_CPUS); |
1027fcb2 | 3626 | mutex_unlock(&trace_types_lock); |
1852fcce SR |
3627 | |
3628 | return ret; | |
3629 | } | |
3630 | ||
577b785f SR |
3631 | struct trace_option_dentry; |
3632 | ||
3633 | static struct trace_option_dentry * | |
2b6080f2 | 3634 | create_trace_option_files(struct trace_array *tr, struct tracer *tracer); |
577b785f SR |
3635 | |
3636 | static void | |
3637 | destroy_trace_option_files(struct trace_option_dentry *topts); | |
3638 | ||
b2821ae6 | 3639 | static int tracing_set_tracer(const char *buf) |
bc0c38d1 | 3640 | { |
577b785f | 3641 | static struct trace_option_dentry *topts; |
bc0c38d1 SR |
3642 | struct trace_array *tr = &global_trace; |
3643 | struct tracer *t; | |
12883efb | 3644 | #ifdef CONFIG_TRACER_MAX_TRACE |
34600f0e | 3645 | bool had_max_tr; |
12883efb | 3646 | #endif |
d9e54076 | 3647 | int ret = 0; |
bc0c38d1 | 3648 | |
1027fcb2 SR |
3649 | mutex_lock(&trace_types_lock); |
3650 | ||
73c5162a | 3651 | if (!ring_buffer_expanded) { |
2b6080f2 | 3652 | ret = __tracing_resize_ring_buffer(tr, trace_buf_size, |
438ced17 | 3653 | RING_BUFFER_ALL_CPUS); |
73c5162a | 3654 | if (ret < 0) |
59f586db | 3655 | goto out; |
73c5162a SR |
3656 | ret = 0; |
3657 | } | |
3658 | ||
bc0c38d1 SR |
3659 | for (t = trace_types; t; t = t->next) { |
3660 | if (strcmp(t->name, buf) == 0) | |
3661 | break; | |
3662 | } | |
c2931e05 FW |
3663 | if (!t) { |
3664 | ret = -EINVAL; | |
3665 | goto out; | |
3666 | } | |
2b6080f2 | 3667 | if (t == tr->current_trace) |
bc0c38d1 SR |
3668 | goto out; |
3669 | ||
9f029e83 | 3670 | trace_branch_disable(); |
613f04a0 | 3671 | |
2b6080f2 | 3672 | tr->current_trace->enabled = false; |
613f04a0 | 3673 | |
2b6080f2 SR |
3674 | if (tr->current_trace->reset) |
3675 | tr->current_trace->reset(tr); | |
34600f0e | 3676 | |
12883efb | 3677 | /* Current trace needs to be nop_trace before synchronize_sched */ |
2b6080f2 | 3678 | tr->current_trace = &nop_trace; |
34600f0e | 3679 | |
45ad21ca SRRH |
3680 | #ifdef CONFIG_TRACER_MAX_TRACE |
3681 | had_max_tr = tr->allocated_snapshot; | |
34600f0e SR |
3682 | |
3683 | if (had_max_tr && !t->use_max_tr) { | |
3684 | /* | |
3685 | * We need to make sure that the update_max_tr sees that | |
3686 | * current_trace changed to nop_trace to keep it from | |
3687 | * swapping the buffers after we resize it. | |
3688 | * The update_max_tr is called from interrupts disabled | |
3689 | * so a synchronized_sched() is sufficient. | |
3690 | */ | |
3691 | synchronize_sched(); | |
3209cff4 | 3692 | free_snapshot(tr); |
ef710e10 | 3693 | } |
12883efb | 3694 | #endif |
577b785f SR |
3695 | destroy_trace_option_files(topts); |
3696 | ||
2b6080f2 | 3697 | topts = create_trace_option_files(tr, t); |
12883efb SRRH |
3698 | |
3699 | #ifdef CONFIG_TRACER_MAX_TRACE | |
34600f0e | 3700 | if (t->use_max_tr && !had_max_tr) { |
3209cff4 | 3701 | ret = alloc_snapshot(tr); |
d60da506 HT |
3702 | if (ret < 0) |
3703 | goto out; | |
ef710e10 | 3704 | } |
12883efb | 3705 | #endif |
577b785f | 3706 | |
1c80025a | 3707 | if (t->init) { |
b6f11df2 | 3708 | ret = tracer_init(t, tr); |
1c80025a FW |
3709 | if (ret) |
3710 | goto out; | |
3711 | } | |
bc0c38d1 | 3712 | |
2b6080f2 SR |
3713 | tr->current_trace = t; |
3714 | tr->current_trace->enabled = true; | |
9f029e83 | 3715 | trace_branch_enable(tr); |
bc0c38d1 SR |
3716 | out: |
3717 | mutex_unlock(&trace_types_lock); | |
3718 | ||
d9e54076 PZ |
3719 | return ret; |
3720 | } | |
3721 | ||
3722 | static ssize_t | |
3723 | tracing_set_trace_write(struct file *filp, const char __user *ubuf, | |
3724 | size_t cnt, loff_t *ppos) | |
3725 | { | |
ee6c2c1b | 3726 | char buf[MAX_TRACER_SIZE+1]; |
d9e54076 PZ |
3727 | int i; |
3728 | size_t ret; | |
e6e7a65a FW |
3729 | int err; |
3730 | ||
3731 | ret = cnt; | |
d9e54076 | 3732 | |
ee6c2c1b LZ |
3733 | if (cnt > MAX_TRACER_SIZE) |
3734 | cnt = MAX_TRACER_SIZE; | |
d9e54076 PZ |
3735 | |
3736 | if (copy_from_user(&buf, ubuf, cnt)) | |
3737 | return -EFAULT; | |
3738 | ||
3739 | buf[cnt] = 0; | |
3740 | ||
3741 | /* strip ending whitespace. */ | |
3742 | for (i = cnt - 1; i > 0 && isspace(buf[i]); i--) | |
3743 | buf[i] = 0; | |
3744 | ||
e6e7a65a FW |
3745 | err = tracing_set_tracer(buf); |
3746 | if (err) | |
3747 | return err; | |
d9e54076 | 3748 | |
cf8517cf | 3749 | *ppos += ret; |
bc0c38d1 | 3750 | |
c2931e05 | 3751 | return ret; |
bc0c38d1 SR |
3752 | } |
3753 | ||
3754 | static ssize_t | |
3755 | tracing_max_lat_read(struct file *filp, char __user *ubuf, | |
3756 | size_t cnt, loff_t *ppos) | |
3757 | { | |
3758 | unsigned long *ptr = filp->private_data; | |
3759 | char buf[64]; | |
3760 | int r; | |
3761 | ||
cffae437 | 3762 | r = snprintf(buf, sizeof(buf), "%ld\n", |
bc0c38d1 | 3763 | *ptr == (unsigned long)-1 ? -1 : nsecs_to_usecs(*ptr)); |
cffae437 SR |
3764 | if (r > sizeof(buf)) |
3765 | r = sizeof(buf); | |
4bf39a94 | 3766 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, r); |
bc0c38d1 SR |
3767 | } |
3768 | ||
3769 | static ssize_t | |
3770 | tracing_max_lat_write(struct file *filp, const char __user *ubuf, | |
3771 | size_t cnt, loff_t *ppos) | |
3772 | { | |
5e39841c | 3773 | unsigned long *ptr = filp->private_data; |
5e39841c | 3774 | unsigned long val; |
c6caeeb1 | 3775 | int ret; |
bc0c38d1 | 3776 | |
22fe9b54 PH |
3777 | ret = kstrtoul_from_user(ubuf, cnt, 10, &val); |
3778 | if (ret) | |
c6caeeb1 | 3779 | return ret; |
bc0c38d1 SR |
3780 | |
3781 | *ptr = val * 1000; | |
3782 | ||
3783 | return cnt; | |
3784 | } | |
3785 | ||
b3806b43 SR |
3786 | static int tracing_open_pipe(struct inode *inode, struct file *filp) |
3787 | { | |
2b6080f2 SR |
3788 | struct trace_cpu *tc = inode->i_private; |
3789 | struct trace_array *tr = tc->tr; | |
b3806b43 | 3790 | struct trace_iterator *iter; |
b04cc6b1 | 3791 | int ret = 0; |
b3806b43 SR |
3792 | |
3793 | if (tracing_disabled) | |
3794 | return -ENODEV; | |
3795 | ||
b04cc6b1 FW |
3796 | mutex_lock(&trace_types_lock); |
3797 | ||
b3806b43 SR |
3798 | /* create a buffer to store the information to pass to userspace */ |
3799 | iter = kzalloc(sizeof(*iter), GFP_KERNEL); | |
b04cc6b1 FW |
3800 | if (!iter) { |
3801 | ret = -ENOMEM; | |
3802 | goto out; | |
3803 | } | |
b3806b43 | 3804 | |
d7350c3f FW |
3805 | /* |
3806 | * We make a copy of the current tracer to avoid concurrent | |
3807 | * changes on it while we are reading. | |
3808 | */ | |
3809 | iter->trace = kmalloc(sizeof(*iter->trace), GFP_KERNEL); | |
3810 | if (!iter->trace) { | |
3811 | ret = -ENOMEM; | |
3812 | goto fail; | |
3813 | } | |
2b6080f2 | 3814 | *iter->trace = *tr->current_trace; |
d7350c3f | 3815 | |
4462344e | 3816 | if (!alloc_cpumask_var(&iter->started, GFP_KERNEL)) { |
b04cc6b1 | 3817 | ret = -ENOMEM; |
d7350c3f | 3818 | goto fail; |
4462344e RR |
3819 | } |
3820 | ||
a309720c | 3821 | /* trace pipe does not show start of buffer */ |
4462344e | 3822 | cpumask_setall(iter->started); |
a309720c | 3823 | |
112f38a7 SR |
3824 | if (trace_flags & TRACE_ITER_LATENCY_FMT) |
3825 | iter->iter_flags |= TRACE_FILE_LAT_FMT; | |
3826 | ||
8be0709f DS |
3827 | /* Output in nanoseconds only if we are using a clock in nanoseconds. */ |
3828 | if (trace_clocks[trace_clock_id].in_ns) | |
3829 | iter->iter_flags |= TRACE_FILE_TIME_IN_NS; | |
3830 | ||
2b6080f2 SR |
3831 | iter->cpu_file = tc->cpu; |
3832 | iter->tr = tc->tr; | |
12883efb | 3833 | iter->trace_buffer = &tc->tr->trace_buffer; |
d7350c3f | 3834 | mutex_init(&iter->mutex); |
b3806b43 SR |
3835 | filp->private_data = iter; |
3836 | ||
107bad8b SR |
3837 | if (iter->trace->pipe_open) |
3838 | iter->trace->pipe_open(iter); | |
107bad8b | 3839 | |
b444786f | 3840 | nonseekable_open(inode, filp); |
b04cc6b1 FW |
3841 | out: |
3842 | mutex_unlock(&trace_types_lock); | |
3843 | return ret; | |
d7350c3f FW |
3844 | |
3845 | fail: | |
3846 | kfree(iter->trace); | |
3847 | kfree(iter); | |
3848 | mutex_unlock(&trace_types_lock); | |
3849 | return ret; | |
b3806b43 SR |
3850 | } |
3851 | ||
3852 | static int tracing_release_pipe(struct inode *inode, struct file *file) | |
3853 | { | |
3854 | struct trace_iterator *iter = file->private_data; | |
3855 | ||
b04cc6b1 FW |
3856 | mutex_lock(&trace_types_lock); |
3857 | ||
29bf4a5e | 3858 | if (iter->trace->pipe_close) |
c521efd1 SR |
3859 | iter->trace->pipe_close(iter); |
3860 | ||
b04cc6b1 FW |
3861 | mutex_unlock(&trace_types_lock); |
3862 | ||
4462344e | 3863 | free_cpumask_var(iter->started); |
d7350c3f FW |
3864 | mutex_destroy(&iter->mutex); |
3865 | kfree(iter->trace); | |
b3806b43 | 3866 | kfree(iter); |
b3806b43 SR |
3867 | |
3868 | return 0; | |
3869 | } | |
3870 | ||
2a2cc8f7 | 3871 | static unsigned int |
cc60cdc9 | 3872 | trace_poll(struct trace_iterator *iter, struct file *filp, poll_table *poll_table) |
2a2cc8f7 | 3873 | { |
15693458 SRRH |
3874 | /* Iterators are static, they should be filled or empty */ |
3875 | if (trace_buffer_iter(iter, iter->cpu_file)) | |
3876 | return POLLIN | POLLRDNORM; | |
2a2cc8f7 | 3877 | |
15693458 | 3878 | if (trace_flags & TRACE_ITER_BLOCK) |
2a2cc8f7 SSP |
3879 | /* |
3880 | * Always select as readable when in blocking mode | |
3881 | */ | |
3882 | return POLLIN | POLLRDNORM; | |
15693458 | 3883 | else |
12883efb | 3884 | return ring_buffer_poll_wait(iter->trace_buffer->buffer, iter->cpu_file, |
15693458 | 3885 | filp, poll_table); |
2a2cc8f7 | 3886 | } |
2a2cc8f7 | 3887 | |
cc60cdc9 SR |
3888 | static unsigned int |
3889 | tracing_poll_pipe(struct file *filp, poll_table *poll_table) | |
3890 | { | |
3891 | struct trace_iterator *iter = filp->private_data; | |
3892 | ||
3893 | return trace_poll(iter, filp, poll_table); | |
2a2cc8f7 SSP |
3894 | } |
3895 | ||
6eaaa5d5 FW |
3896 | /* |
3897 | * This is a make-shift waitqueue. | |
3898 | * A tracer might use this callback on some rare cases: | |
3899 | * | |
3900 | * 1) the current tracer might hold the runqueue lock when it wakes up | |
3901 | * a reader, hence a deadlock (sched, function, and function graph tracers) | |
3902 | * 2) the function tracers, trace all functions, we don't want | |
3903 | * the overhead of calling wake_up and friends | |
3904 | * (and tracing them too) | |
3905 | * | |
3906 | * Anyway, this is really very primitive wakeup. | |
3907 | */ | |
3908 | void poll_wait_pipe(struct trace_iterator *iter) | |
3909 | { | |
3910 | set_current_state(TASK_INTERRUPTIBLE); | |
3911 | /* sleep for 100 msecs, and try again. */ | |
3912 | schedule_timeout(HZ / 10); | |
3913 | } | |
3914 | ||
ff98781b EGM |
3915 | /* Must be called with trace_types_lock mutex held. */ |
3916 | static int tracing_wait_pipe(struct file *filp) | |
b3806b43 SR |
3917 | { |
3918 | struct trace_iterator *iter = filp->private_data; | |
b3806b43 | 3919 | |
b3806b43 | 3920 | while (trace_empty(iter)) { |
2dc8f095 | 3921 | |
107bad8b | 3922 | if ((filp->f_flags & O_NONBLOCK)) { |
ff98781b | 3923 | return -EAGAIN; |
107bad8b | 3924 | } |
2dc8f095 | 3925 | |
d7350c3f | 3926 | mutex_unlock(&iter->mutex); |
107bad8b | 3927 | |
6eaaa5d5 | 3928 | iter->trace->wait_pipe(iter); |
b3806b43 | 3929 | |
d7350c3f | 3930 | mutex_lock(&iter->mutex); |
107bad8b | 3931 | |
6eaaa5d5 | 3932 | if (signal_pending(current)) |
ff98781b | 3933 | return -EINTR; |
b3806b43 SR |
3934 | |
3935 | /* | |
250bfd3d | 3936 | * We block until we read something and tracing is disabled. |
b3806b43 SR |
3937 | * We still block if tracing is disabled, but we have never |
3938 | * read anything. This allows a user to cat this file, and | |
3939 | * then enable tracing. But after we have read something, | |
3940 | * we give an EOF when tracing is again disabled. | |
3941 | * | |
3942 | * iter->pos will be 0 if we haven't read anything. | |
3943 | */ | |
250bfd3d | 3944 | if (!tracing_is_enabled() && iter->pos) |
b3806b43 | 3945 | break; |
b3806b43 SR |
3946 | } |
3947 | ||
ff98781b EGM |
3948 | return 1; |
3949 | } | |
3950 | ||
3951 | /* | |
3952 | * Consumer reader. | |
3953 | */ | |
3954 | static ssize_t | |
3955 | tracing_read_pipe(struct file *filp, char __user *ubuf, | |
3956 | size_t cnt, loff_t *ppos) | |
3957 | { | |
3958 | struct trace_iterator *iter = filp->private_data; | |
2b6080f2 | 3959 | struct trace_array *tr = iter->tr; |
ff98781b EGM |
3960 | ssize_t sret; |
3961 | ||
3962 | /* return any leftover data */ | |
3963 | sret = trace_seq_to_user(&iter->seq, ubuf, cnt); | |
3964 | if (sret != -EBUSY) | |
3965 | return sret; | |
3966 | ||
f9520750 | 3967 | trace_seq_init(&iter->seq); |
ff98781b | 3968 | |
d7350c3f | 3969 | /* copy the tracer to avoid using a global lock all around */ |
ff98781b | 3970 | mutex_lock(&trace_types_lock); |
2b6080f2 SR |
3971 | if (unlikely(iter->trace->name != tr->current_trace->name)) |
3972 | *iter->trace = *tr->current_trace; | |
d7350c3f FW |
3973 | mutex_unlock(&trace_types_lock); |
3974 | ||
3975 | /* | |
3976 | * Avoid more than one consumer on a single file descriptor | |
3977 | * This is just a matter of traces coherency, the ring buffer itself | |
3978 | * is protected. | |
3979 | */ | |
3980 | mutex_lock(&iter->mutex); | |
ff98781b EGM |
3981 | if (iter->trace->read) { |
3982 | sret = iter->trace->read(iter, filp, ubuf, cnt, ppos); | |
3983 | if (sret) | |
3984 | goto out; | |
3985 | } | |
3986 | ||
3987 | waitagain: | |
3988 | sret = tracing_wait_pipe(filp); | |
3989 | if (sret <= 0) | |
3990 | goto out; | |
3991 | ||
b3806b43 | 3992 | /* stop when tracing is finished */ |
ff98781b EGM |
3993 | if (trace_empty(iter)) { |
3994 | sret = 0; | |
107bad8b | 3995 | goto out; |
ff98781b | 3996 | } |
b3806b43 SR |
3997 | |
3998 | if (cnt >= PAGE_SIZE) | |
3999 | cnt = PAGE_SIZE - 1; | |
4000 | ||
53d0aa77 | 4001 | /* reset all but tr, trace, and overruns */ |
53d0aa77 SR |
4002 | memset(&iter->seq, 0, |
4003 | sizeof(struct trace_iterator) - | |
4004 | offsetof(struct trace_iterator, seq)); | |
4823ed7e | 4005 | iter->pos = -1; |
b3806b43 | 4006 | |
4f535968 | 4007 | trace_event_read_lock(); |
7e53bd42 | 4008 | trace_access_lock(iter->cpu_file); |
955b61e5 | 4009 | while (trace_find_next_entry_inc(iter) != NULL) { |
2c4f035f | 4010 | enum print_line_t ret; |
088b1e42 SR |
4011 | int len = iter->seq.len; |
4012 | ||
f9896bf3 | 4013 | ret = print_trace_line(iter); |
2c4f035f | 4014 | if (ret == TRACE_TYPE_PARTIAL_LINE) { |
088b1e42 SR |
4015 | /* don't print partial lines */ |
4016 | iter->seq.len = len; | |
b3806b43 | 4017 | break; |
088b1e42 | 4018 | } |
b91facc3 FW |
4019 | if (ret != TRACE_TYPE_NO_CONSUME) |
4020 | trace_consume(iter); | |
b3806b43 SR |
4021 | |
4022 | if (iter->seq.len >= cnt) | |
4023 | break; | |
ee5e51f5 JO |
4024 | |
4025 | /* | |
4026 | * Setting the full flag means we reached the trace_seq buffer | |
4027 | * size and we should leave by partial output condition above. | |
4028 | * One of the trace_seq_* functions is not used properly. | |
4029 | */ | |
4030 | WARN_ONCE(iter->seq.full, "full flag set for trace type %d", | |
4031 | iter->ent->type); | |
b3806b43 | 4032 | } |
7e53bd42 | 4033 | trace_access_unlock(iter->cpu_file); |
4f535968 | 4034 | trace_event_read_unlock(); |
b3806b43 | 4035 | |
b3806b43 | 4036 | /* Now copy what we have to the user */ |
6c6c2796 PP |
4037 | sret = trace_seq_to_user(&iter->seq, ubuf, cnt); |
4038 | if (iter->seq.readpos >= iter->seq.len) | |
f9520750 | 4039 | trace_seq_init(&iter->seq); |
9ff4b974 PP |
4040 | |
4041 | /* | |
25985edc | 4042 | * If there was nothing to send to user, in spite of consuming trace |
9ff4b974 PP |
4043 | * entries, go back to wait for more entries. |
4044 | */ | |
6c6c2796 | 4045 | if (sret == -EBUSY) |
9ff4b974 | 4046 | goto waitagain; |
b3806b43 | 4047 | |
107bad8b | 4048 | out: |
d7350c3f | 4049 | mutex_unlock(&iter->mutex); |
107bad8b | 4050 | |
6c6c2796 | 4051 | return sret; |
b3806b43 SR |
4052 | } |
4053 | ||
3c56819b EGM |
4054 | static void tracing_pipe_buf_release(struct pipe_inode_info *pipe, |
4055 | struct pipe_buffer *buf) | |
4056 | { | |
4057 | __free_page(buf->page); | |
4058 | } | |
4059 | ||
4060 | static void tracing_spd_release_pipe(struct splice_pipe_desc *spd, | |
4061 | unsigned int idx) | |
4062 | { | |
4063 | __free_page(spd->pages[idx]); | |
4064 | } | |
4065 | ||
28dfef8f | 4066 | static const struct pipe_buf_operations tracing_pipe_buf_ops = { |
34cd4998 SR |
4067 | .can_merge = 0, |
4068 | .map = generic_pipe_buf_map, | |
4069 | .unmap = generic_pipe_buf_unmap, | |
4070 | .confirm = generic_pipe_buf_confirm, | |
4071 | .release = tracing_pipe_buf_release, | |
4072 | .steal = generic_pipe_buf_steal, | |
4073 | .get = generic_pipe_buf_get, | |
3c56819b EGM |
4074 | }; |
4075 | ||
34cd4998 | 4076 | static size_t |
fa7c7f6e | 4077 | tracing_fill_pipe_page(size_t rem, struct trace_iterator *iter) |
34cd4998 SR |
4078 | { |
4079 | size_t count; | |
4080 | int ret; | |
4081 | ||
4082 | /* Seq buffer is page-sized, exactly what we need. */ | |
4083 | for (;;) { | |
4084 | count = iter->seq.len; | |
4085 | ret = print_trace_line(iter); | |
4086 | count = iter->seq.len - count; | |
4087 | if (rem < count) { | |
4088 | rem = 0; | |
4089 | iter->seq.len -= count; | |
4090 | break; | |
4091 | } | |
4092 | if (ret == TRACE_TYPE_PARTIAL_LINE) { | |
4093 | iter->seq.len -= count; | |
4094 | break; | |
4095 | } | |
4096 | ||
74e7ff8c LJ |
4097 | if (ret != TRACE_TYPE_NO_CONSUME) |
4098 | trace_consume(iter); | |
34cd4998 | 4099 | rem -= count; |
955b61e5 | 4100 | if (!trace_find_next_entry_inc(iter)) { |
34cd4998 SR |
4101 | rem = 0; |
4102 | iter->ent = NULL; | |
4103 | break; | |
4104 | } | |
4105 | } | |
4106 | ||
4107 | return rem; | |
4108 | } | |
4109 | ||
3c56819b EGM |
4110 | static ssize_t tracing_splice_read_pipe(struct file *filp, |
4111 | loff_t *ppos, | |
4112 | struct pipe_inode_info *pipe, | |
4113 | size_t len, | |
4114 | unsigned int flags) | |
4115 | { | |
35f3d14d JA |
4116 | struct page *pages_def[PIPE_DEF_BUFFERS]; |
4117 | struct partial_page partial_def[PIPE_DEF_BUFFERS]; | |
3c56819b EGM |
4118 | struct trace_iterator *iter = filp->private_data; |
4119 | struct splice_pipe_desc spd = { | |
35f3d14d JA |
4120 | .pages = pages_def, |
4121 | .partial = partial_def, | |
34cd4998 | 4122 | .nr_pages = 0, /* This gets updated below. */ |
047fe360 | 4123 | .nr_pages_max = PIPE_DEF_BUFFERS, |
34cd4998 SR |
4124 | .flags = flags, |
4125 | .ops = &tracing_pipe_buf_ops, | |
4126 | .spd_release = tracing_spd_release_pipe, | |
3c56819b | 4127 | }; |
2b6080f2 | 4128 | struct trace_array *tr = iter->tr; |
3c56819b | 4129 | ssize_t ret; |
34cd4998 | 4130 | size_t rem; |
3c56819b EGM |
4131 | unsigned int i; |
4132 | ||
35f3d14d JA |
4133 | if (splice_grow_spd(pipe, &spd)) |
4134 | return -ENOMEM; | |
4135 | ||
d7350c3f | 4136 | /* copy the tracer to avoid using a global lock all around */ |
3c56819b | 4137 | mutex_lock(&trace_types_lock); |
2b6080f2 SR |
4138 | if (unlikely(iter->trace->name != tr->current_trace->name)) |
4139 | *iter->trace = *tr->current_trace; | |
d7350c3f FW |
4140 | mutex_unlock(&trace_types_lock); |
4141 | ||
4142 | mutex_lock(&iter->mutex); | |
3c56819b EGM |
4143 | |
4144 | if (iter->trace->splice_read) { | |
4145 | ret = iter->trace->splice_read(iter, filp, | |
4146 | ppos, pipe, len, flags); | |
4147 | if (ret) | |
34cd4998 | 4148 | goto out_err; |
3c56819b EGM |
4149 | } |
4150 | ||
4151 | ret = tracing_wait_pipe(filp); | |
4152 | if (ret <= 0) | |
34cd4998 | 4153 | goto out_err; |
3c56819b | 4154 | |
955b61e5 | 4155 | if (!iter->ent && !trace_find_next_entry_inc(iter)) { |
3c56819b | 4156 | ret = -EFAULT; |
34cd4998 | 4157 | goto out_err; |
3c56819b EGM |
4158 | } |
4159 | ||
4f535968 | 4160 | trace_event_read_lock(); |
7e53bd42 | 4161 | trace_access_lock(iter->cpu_file); |
4f535968 | 4162 | |
3c56819b | 4163 | /* Fill as many pages as possible. */ |
35f3d14d JA |
4164 | for (i = 0, rem = len; i < pipe->buffers && rem; i++) { |
4165 | spd.pages[i] = alloc_page(GFP_KERNEL); | |
4166 | if (!spd.pages[i]) | |
34cd4998 | 4167 | break; |
3c56819b | 4168 | |
fa7c7f6e | 4169 | rem = tracing_fill_pipe_page(rem, iter); |
3c56819b EGM |
4170 | |
4171 | /* Copy the data into the page, so we can start over. */ | |
4172 | ret = trace_seq_to_buffer(&iter->seq, | |
35f3d14d | 4173 | page_address(spd.pages[i]), |
3c56819b EGM |
4174 | iter->seq.len); |
4175 | if (ret < 0) { | |
35f3d14d | 4176 | __free_page(spd.pages[i]); |
3c56819b EGM |
4177 | break; |
4178 | } | |
35f3d14d JA |
4179 | spd.partial[i].offset = 0; |
4180 | spd.partial[i].len = iter->seq.len; | |
3c56819b | 4181 | |
f9520750 | 4182 | trace_seq_init(&iter->seq); |
3c56819b EGM |
4183 | } |
4184 | ||
7e53bd42 | 4185 | trace_access_unlock(iter->cpu_file); |
4f535968 | 4186 | trace_event_read_unlock(); |
d7350c3f | 4187 | mutex_unlock(&iter->mutex); |
3c56819b EGM |
4188 | |
4189 | spd.nr_pages = i; | |
4190 | ||
35f3d14d JA |
4191 | ret = splice_to_pipe(pipe, &spd); |
4192 | out: | |
047fe360 | 4193 | splice_shrink_spd(&spd); |
35f3d14d | 4194 | return ret; |
3c56819b | 4195 | |
34cd4998 | 4196 | out_err: |
d7350c3f | 4197 | mutex_unlock(&iter->mutex); |
35f3d14d | 4198 | goto out; |
3c56819b EGM |
4199 | } |
4200 | ||
a98a3c3f SR |
4201 | static ssize_t |
4202 | tracing_entries_read(struct file *filp, char __user *ubuf, | |
4203 | size_t cnt, loff_t *ppos) | |
4204 | { | |
2b6080f2 SR |
4205 | struct trace_cpu *tc = filp->private_data; |
4206 | struct trace_array *tr = tc->tr; | |
438ced17 VN |
4207 | char buf[64]; |
4208 | int r = 0; | |
4209 | ssize_t ret; | |
a98a3c3f | 4210 | |
db526ca3 | 4211 | mutex_lock(&trace_types_lock); |
438ced17 | 4212 | |
2b6080f2 | 4213 | if (tc->cpu == RING_BUFFER_ALL_CPUS) { |
438ced17 VN |
4214 | int cpu, buf_size_same; |
4215 | unsigned long size; | |
4216 | ||
4217 | size = 0; | |
4218 | buf_size_same = 1; | |
4219 | /* check if all cpu sizes are same */ | |
4220 | for_each_tracing_cpu(cpu) { | |
4221 | /* fill in the size from first enabled cpu */ | |
4222 | if (size == 0) | |
12883efb SRRH |
4223 | size = per_cpu_ptr(tr->trace_buffer.data, cpu)->entries; |
4224 | if (size != per_cpu_ptr(tr->trace_buffer.data, cpu)->entries) { | |
438ced17 VN |
4225 | buf_size_same = 0; |
4226 | break; | |
4227 | } | |
4228 | } | |
4229 | ||
4230 | if (buf_size_same) { | |
4231 | if (!ring_buffer_expanded) | |
4232 | r = sprintf(buf, "%lu (expanded: %lu)\n", | |
4233 | size >> 10, | |
4234 | trace_buf_size >> 10); | |
4235 | else | |
4236 | r = sprintf(buf, "%lu\n", size >> 10); | |
4237 | } else | |
4238 | r = sprintf(buf, "X\n"); | |
4239 | } else | |
12883efb | 4240 | r = sprintf(buf, "%lu\n", per_cpu_ptr(tr->trace_buffer.data, tc->cpu)->entries >> 10); |
438ced17 | 4241 | |
db526ca3 SR |
4242 | mutex_unlock(&trace_types_lock); |
4243 | ||
438ced17 VN |
4244 | ret = simple_read_from_buffer(ubuf, cnt, ppos, buf, r); |
4245 | return ret; | |
a98a3c3f SR |
4246 | } |
4247 | ||
4248 | static ssize_t | |
4249 | tracing_entries_write(struct file *filp, const char __user *ubuf, | |
4250 | size_t cnt, loff_t *ppos) | |
4251 | { | |
2b6080f2 | 4252 | struct trace_cpu *tc = filp->private_data; |
a98a3c3f | 4253 | unsigned long val; |
4f271a2a | 4254 | int ret; |
a98a3c3f | 4255 | |
22fe9b54 PH |
4256 | ret = kstrtoul_from_user(ubuf, cnt, 10, &val); |
4257 | if (ret) | |
c6caeeb1 | 4258 | return ret; |
a98a3c3f SR |
4259 | |
4260 | /* must have at least 1 entry */ | |
4261 | if (!val) | |
4262 | return -EINVAL; | |
4263 | ||
1696b2b0 SR |
4264 | /* value is in KB */ |
4265 | val <<= 10; | |
4266 | ||
2b6080f2 | 4267 | ret = tracing_resize_ring_buffer(tc->tr, val, tc->cpu); |
4f271a2a VN |
4268 | if (ret < 0) |
4269 | return ret; | |
a98a3c3f | 4270 | |
cf8517cf | 4271 | *ppos += cnt; |
a98a3c3f | 4272 | |
4f271a2a VN |
4273 | return cnt; |
4274 | } | |
bf5e6519 | 4275 | |
f81ab074 VN |
4276 | static ssize_t |
4277 | tracing_total_entries_read(struct file *filp, char __user *ubuf, | |
4278 | size_t cnt, loff_t *ppos) | |
4279 | { | |
4280 | struct trace_array *tr = filp->private_data; | |
4281 | char buf[64]; | |
4282 | int r, cpu; | |
4283 | unsigned long size = 0, expanded_size = 0; | |
4284 | ||
4285 | mutex_lock(&trace_types_lock); | |
4286 | for_each_tracing_cpu(cpu) { | |
12883efb | 4287 | size += per_cpu_ptr(tr->trace_buffer.data, cpu)->entries >> 10; |
f81ab074 VN |
4288 | if (!ring_buffer_expanded) |
4289 | expanded_size += trace_buf_size >> 10; | |
4290 | } | |
4291 | if (ring_buffer_expanded) | |
4292 | r = sprintf(buf, "%lu\n", size); | |
4293 | else | |
4294 | r = sprintf(buf, "%lu (expanded: %lu)\n", size, expanded_size); | |
4295 | mutex_unlock(&trace_types_lock); | |
4296 | ||
4297 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, r); | |
4298 | } | |
4299 | ||
4f271a2a VN |
4300 | static ssize_t |
4301 | tracing_free_buffer_write(struct file *filp, const char __user *ubuf, | |
4302 | size_t cnt, loff_t *ppos) | |
4303 | { | |
4304 | /* | |
4305 | * There is no need to read what the user has written, this function | |
4306 | * is just to make sure that there is no error when "echo" is used | |
4307 | */ | |
4308 | ||
4309 | *ppos += cnt; | |
a98a3c3f SR |
4310 | |
4311 | return cnt; | |
4312 | } | |
4313 | ||
4f271a2a VN |
4314 | static int |
4315 | tracing_free_buffer_release(struct inode *inode, struct file *filp) | |
4316 | { | |
2b6080f2 SR |
4317 | struct trace_array *tr = inode->i_private; |
4318 | ||
cf30cf67 SR |
4319 | /* disable tracing ? */ |
4320 | if (trace_flags & TRACE_ITER_STOP_ON_FREE) | |
4321 | tracing_off(); | |
4f271a2a | 4322 | /* resize the ring buffer to 0 */ |
2b6080f2 | 4323 | tracing_resize_ring_buffer(tr, 0, RING_BUFFER_ALL_CPUS); |
4f271a2a VN |
4324 | |
4325 | return 0; | |
4326 | } | |
4327 | ||
5bf9a1ee PP |
4328 | static ssize_t |
4329 | tracing_mark_write(struct file *filp, const char __user *ubuf, | |
4330 | size_t cnt, loff_t *fpos) | |
4331 | { | |
d696b58c SR |
4332 | unsigned long addr = (unsigned long)ubuf; |
4333 | struct ring_buffer_event *event; | |
4334 | struct ring_buffer *buffer; | |
4335 | struct print_entry *entry; | |
4336 | unsigned long irq_flags; | |
4337 | struct page *pages[2]; | |
6edb2a8a | 4338 | void *map_page[2]; |
d696b58c SR |
4339 | int nr_pages = 1; |
4340 | ssize_t written; | |
d696b58c SR |
4341 | int offset; |
4342 | int size; | |
4343 | int len; | |
4344 | int ret; | |
6edb2a8a | 4345 | int i; |
5bf9a1ee | 4346 | |
c76f0694 | 4347 | if (tracing_disabled) |
5bf9a1ee PP |
4348 | return -EINVAL; |
4349 | ||
5224c3a3 MSB |
4350 | if (!(trace_flags & TRACE_ITER_MARKERS)) |
4351 | return -EINVAL; | |
4352 | ||
5bf9a1ee PP |
4353 | if (cnt > TRACE_BUF_SIZE) |
4354 | cnt = TRACE_BUF_SIZE; | |
4355 | ||
d696b58c SR |
4356 | /* |
4357 | * Userspace is injecting traces into the kernel trace buffer. | |
4358 | * We want to be as non intrusive as possible. | |
4359 | * To do so, we do not want to allocate any special buffers | |
4360 | * or take any locks, but instead write the userspace data | |
4361 | * straight into the ring buffer. | |
4362 | * | |
4363 | * First we need to pin the userspace buffer into memory, | |
4364 | * which, most likely it is, because it just referenced it. | |
4365 | * But there's no guarantee that it is. By using get_user_pages_fast() | |
4366 | * and kmap_atomic/kunmap_atomic() we can get access to the | |
4367 | * pages directly. We then write the data directly into the | |
4368 | * ring buffer. | |
4369 | */ | |
4370 | BUILD_BUG_ON(TRACE_BUF_SIZE >= PAGE_SIZE); | |
5bf9a1ee | 4371 | |
d696b58c SR |
4372 | /* check if we cross pages */ |
4373 | if ((addr & PAGE_MASK) != ((addr + cnt) & PAGE_MASK)) | |
4374 | nr_pages = 2; | |
4375 | ||
4376 | offset = addr & (PAGE_SIZE - 1); | |
4377 | addr &= PAGE_MASK; | |
4378 | ||
4379 | ret = get_user_pages_fast(addr, nr_pages, 0, pages); | |
4380 | if (ret < nr_pages) { | |
4381 | while (--ret >= 0) | |
4382 | put_page(pages[ret]); | |
4383 | written = -EFAULT; | |
4384 | goto out; | |
5bf9a1ee | 4385 | } |
d696b58c | 4386 | |
6edb2a8a SR |
4387 | for (i = 0; i < nr_pages; i++) |
4388 | map_page[i] = kmap_atomic(pages[i]); | |
d696b58c SR |
4389 | |
4390 | local_save_flags(irq_flags); | |
4391 | size = sizeof(*entry) + cnt + 2; /* possible \n added */ | |
12883efb | 4392 | buffer = global_trace.trace_buffer.buffer; |
d696b58c SR |
4393 | event = trace_buffer_lock_reserve(buffer, TRACE_PRINT, size, |
4394 | irq_flags, preempt_count()); | |
4395 | if (!event) { | |
4396 | /* Ring buffer disabled, return as if not open for write */ | |
4397 | written = -EBADF; | |
4398 | goto out_unlock; | |
5bf9a1ee | 4399 | } |
d696b58c SR |
4400 | |
4401 | entry = ring_buffer_event_data(event); | |
4402 | entry->ip = _THIS_IP_; | |
4403 | ||
4404 | if (nr_pages == 2) { | |
4405 | len = PAGE_SIZE - offset; | |
6edb2a8a SR |
4406 | memcpy(&entry->buf, map_page[0] + offset, len); |
4407 | memcpy(&entry->buf[len], map_page[1], cnt - len); | |
c13d2f7c | 4408 | } else |
6edb2a8a | 4409 | memcpy(&entry->buf, map_page[0] + offset, cnt); |
5bf9a1ee | 4410 | |
d696b58c SR |
4411 | if (entry->buf[cnt - 1] != '\n') { |
4412 | entry->buf[cnt] = '\n'; | |
4413 | entry->buf[cnt + 1] = '\0'; | |
4414 | } else | |
4415 | entry->buf[cnt] = '\0'; | |
4416 | ||
7ffbd48d | 4417 | __buffer_unlock_commit(buffer, event); |
5bf9a1ee | 4418 | |
d696b58c | 4419 | written = cnt; |
5bf9a1ee | 4420 | |
d696b58c | 4421 | *fpos += written; |
1aa54bca | 4422 | |
d696b58c | 4423 | out_unlock: |
6edb2a8a SR |
4424 | for (i = 0; i < nr_pages; i++){ |
4425 | kunmap_atomic(map_page[i]); | |
4426 | put_page(pages[i]); | |
4427 | } | |
d696b58c | 4428 | out: |
1aa54bca | 4429 | return written; |
5bf9a1ee PP |
4430 | } |
4431 | ||
13f16d20 | 4432 | static int tracing_clock_show(struct seq_file *m, void *v) |
5079f326 | 4433 | { |
2b6080f2 | 4434 | struct trace_array *tr = m->private; |
5079f326 Z |
4435 | int i; |
4436 | ||
4437 | for (i = 0; i < ARRAY_SIZE(trace_clocks); i++) | |
13f16d20 | 4438 | seq_printf(m, |
5079f326 | 4439 | "%s%s%s%s", i ? " " : "", |
2b6080f2 SR |
4440 | i == tr->clock_id ? "[" : "", trace_clocks[i].name, |
4441 | i == tr->clock_id ? "]" : ""); | |
13f16d20 | 4442 | seq_putc(m, '\n'); |
5079f326 | 4443 | |
13f16d20 | 4444 | return 0; |
5079f326 Z |
4445 | } |
4446 | ||
4447 | static ssize_t tracing_clock_write(struct file *filp, const char __user *ubuf, | |
4448 | size_t cnt, loff_t *fpos) | |
4449 | { | |
2b6080f2 SR |
4450 | struct seq_file *m = filp->private_data; |
4451 | struct trace_array *tr = m->private; | |
5079f326 Z |
4452 | char buf[64]; |
4453 | const char *clockstr; | |
4454 | int i; | |
4455 | ||
4456 | if (cnt >= sizeof(buf)) | |
4457 | return -EINVAL; | |
4458 | ||
4459 | if (copy_from_user(&buf, ubuf, cnt)) | |
4460 | return -EFAULT; | |
4461 | ||
4462 | buf[cnt] = 0; | |
4463 | ||
4464 | clockstr = strstrip(buf); | |
4465 | ||
4466 | for (i = 0; i < ARRAY_SIZE(trace_clocks); i++) { | |
4467 | if (strcmp(trace_clocks[i].name, clockstr) == 0) | |
4468 | break; | |
4469 | } | |
4470 | if (i == ARRAY_SIZE(trace_clocks)) | |
4471 | return -EINVAL; | |
4472 | ||
5079f326 Z |
4473 | mutex_lock(&trace_types_lock); |
4474 | ||
2b6080f2 SR |
4475 | tr->clock_id = i; |
4476 | ||
12883efb | 4477 | ring_buffer_set_clock(tr->trace_buffer.buffer, trace_clocks[i].func); |
5079f326 | 4478 | |
60303ed3 DS |
4479 | /* |
4480 | * New clock may not be consistent with the previous clock. | |
4481 | * Reset the buffer so that it doesn't have incomparable timestamps. | |
4482 | */ | |
12883efb SRRH |
4483 | tracing_reset_online_cpus(&global_trace.trace_buffer); |
4484 | ||
4485 | #ifdef CONFIG_TRACER_MAX_TRACE | |
4486 | if (tr->flags & TRACE_ARRAY_FL_GLOBAL && tr->max_buffer.buffer) | |
4487 | ring_buffer_set_clock(tr->max_buffer.buffer, trace_clocks[i].func); | |
4488 | tracing_reset_online_cpus(&global_trace.max_buffer); | |
4489 | #endif | |
60303ed3 | 4490 | |
5079f326 Z |
4491 | mutex_unlock(&trace_types_lock); |
4492 | ||
4493 | *fpos += cnt; | |
4494 | ||
4495 | return cnt; | |
4496 | } | |
4497 | ||
13f16d20 LZ |
4498 | static int tracing_clock_open(struct inode *inode, struct file *file) |
4499 | { | |
4500 | if (tracing_disabled) | |
4501 | return -ENODEV; | |
2b6080f2 SR |
4502 | |
4503 | return single_open(file, tracing_clock_show, inode->i_private); | |
13f16d20 LZ |
4504 | } |
4505 | ||
6de58e62 SRRH |
4506 | struct ftrace_buffer_info { |
4507 | struct trace_iterator iter; | |
4508 | void *spare; | |
4509 | unsigned int read; | |
4510 | }; | |
4511 | ||
debdd57f HT |
4512 | #ifdef CONFIG_TRACER_SNAPSHOT |
4513 | static int tracing_snapshot_open(struct inode *inode, struct file *file) | |
4514 | { | |
2b6080f2 | 4515 | struct trace_cpu *tc = inode->i_private; |
debdd57f | 4516 | struct trace_iterator *iter; |
2b6080f2 | 4517 | struct seq_file *m; |
debdd57f HT |
4518 | int ret = 0; |
4519 | ||
4520 | if (file->f_mode & FMODE_READ) { | |
4521 | iter = __tracing_open(inode, file, true); | |
4522 | if (IS_ERR(iter)) | |
4523 | ret = PTR_ERR(iter); | |
2b6080f2 SR |
4524 | } else { |
4525 | /* Writes still need the seq_file to hold the private data */ | |
4526 | m = kzalloc(sizeof(*m), GFP_KERNEL); | |
4527 | if (!m) | |
4528 | return -ENOMEM; | |
4529 | iter = kzalloc(sizeof(*iter), GFP_KERNEL); | |
4530 | if (!iter) { | |
4531 | kfree(m); | |
4532 | return -ENOMEM; | |
4533 | } | |
4534 | iter->tr = tc->tr; | |
12883efb | 4535 | iter->trace_buffer = &tc->tr->max_buffer; |
f1affcaa | 4536 | iter->cpu_file = tc->cpu; |
2b6080f2 SR |
4537 | m->private = iter; |
4538 | file->private_data = m; | |
debdd57f | 4539 | } |
2b6080f2 | 4540 | |
debdd57f HT |
4541 | return ret; |
4542 | } | |
4543 | ||
4544 | static ssize_t | |
4545 | tracing_snapshot_write(struct file *filp, const char __user *ubuf, size_t cnt, | |
4546 | loff_t *ppos) | |
4547 | { | |
2b6080f2 SR |
4548 | struct seq_file *m = filp->private_data; |
4549 | struct trace_iterator *iter = m->private; | |
4550 | struct trace_array *tr = iter->tr; | |
debdd57f HT |
4551 | unsigned long val; |
4552 | int ret; | |
4553 | ||
4554 | ret = tracing_update_buffers(); | |
4555 | if (ret < 0) | |
4556 | return ret; | |
4557 | ||
4558 | ret = kstrtoul_from_user(ubuf, cnt, 10, &val); | |
4559 | if (ret) | |
4560 | return ret; | |
4561 | ||
4562 | mutex_lock(&trace_types_lock); | |
4563 | ||
2b6080f2 | 4564 | if (tr->current_trace->use_max_tr) { |
debdd57f HT |
4565 | ret = -EBUSY; |
4566 | goto out; | |
4567 | } | |
4568 | ||
4569 | switch (val) { | |
4570 | case 0: | |
f1affcaa SRRH |
4571 | if (iter->cpu_file != RING_BUFFER_ALL_CPUS) { |
4572 | ret = -EINVAL; | |
4573 | break; | |
debdd57f | 4574 | } |
3209cff4 SRRH |
4575 | if (tr->allocated_snapshot) |
4576 | free_snapshot(tr); | |
debdd57f HT |
4577 | break; |
4578 | case 1: | |
f1affcaa SRRH |
4579 | /* Only allow per-cpu swap if the ring buffer supports it */ |
4580 | #ifndef CONFIG_RING_BUFFER_ALLOW_SWAP | |
4581 | if (iter->cpu_file != RING_BUFFER_ALL_CPUS) { | |
4582 | ret = -EINVAL; | |
4583 | break; | |
4584 | } | |
4585 | #endif | |
45ad21ca | 4586 | if (!tr->allocated_snapshot) { |
3209cff4 | 4587 | ret = alloc_snapshot(tr); |
debdd57f HT |
4588 | if (ret < 0) |
4589 | break; | |
debdd57f | 4590 | } |
debdd57f HT |
4591 | local_irq_disable(); |
4592 | /* Now, we're going to swap */ | |
f1affcaa | 4593 | if (iter->cpu_file == RING_BUFFER_ALL_CPUS) |
ce9bae55 | 4594 | update_max_tr(tr, current, smp_processor_id()); |
f1affcaa | 4595 | else |
ce9bae55 | 4596 | update_max_tr_single(tr, current, iter->cpu_file); |
debdd57f HT |
4597 | local_irq_enable(); |
4598 | break; | |
4599 | default: | |
45ad21ca | 4600 | if (tr->allocated_snapshot) { |
f1affcaa SRRH |
4601 | if (iter->cpu_file == RING_BUFFER_ALL_CPUS) |
4602 | tracing_reset_online_cpus(&tr->max_buffer); | |
4603 | else | |
4604 | tracing_reset(&tr->max_buffer, iter->cpu_file); | |
4605 | } | |
debdd57f HT |
4606 | break; |
4607 | } | |
4608 | ||
4609 | if (ret >= 0) { | |
4610 | *ppos += cnt; | |
4611 | ret = cnt; | |
4612 | } | |
4613 | out: | |
4614 | mutex_unlock(&trace_types_lock); | |
4615 | return ret; | |
4616 | } | |
2b6080f2 SR |
4617 | |
4618 | static int tracing_snapshot_release(struct inode *inode, struct file *file) | |
4619 | { | |
4620 | struct seq_file *m = file->private_data; | |
4621 | ||
4622 | if (file->f_mode & FMODE_READ) | |
4623 | return tracing_release(inode, file); | |
4624 | ||
4625 | /* If write only, the seq_file is just a stub */ | |
4626 | if (m) | |
4627 | kfree(m->private); | |
4628 | kfree(m); | |
4629 | ||
4630 | return 0; | |
4631 | } | |
4632 | ||
6de58e62 SRRH |
4633 | static int tracing_buffers_open(struct inode *inode, struct file *filp); |
4634 | static ssize_t tracing_buffers_read(struct file *filp, char __user *ubuf, | |
4635 | size_t count, loff_t *ppos); | |
4636 | static int tracing_buffers_release(struct inode *inode, struct file *file); | |
4637 | static ssize_t tracing_buffers_splice_read(struct file *file, loff_t *ppos, | |
4638 | struct pipe_inode_info *pipe, size_t len, unsigned int flags); | |
4639 | ||
4640 | static int snapshot_raw_open(struct inode *inode, struct file *filp) | |
4641 | { | |
4642 | struct ftrace_buffer_info *info; | |
4643 | int ret; | |
4644 | ||
4645 | ret = tracing_buffers_open(inode, filp); | |
4646 | if (ret < 0) | |
4647 | return ret; | |
4648 | ||
4649 | info = filp->private_data; | |
4650 | ||
4651 | if (info->iter.trace->use_max_tr) { | |
4652 | tracing_buffers_release(inode, filp); | |
4653 | return -EBUSY; | |
4654 | } | |
4655 | ||
4656 | info->iter.snapshot = true; | |
4657 | info->iter.trace_buffer = &info->iter.tr->max_buffer; | |
4658 | ||
4659 | return ret; | |
4660 | } | |
4661 | ||
debdd57f HT |
4662 | #endif /* CONFIG_TRACER_SNAPSHOT */ |
4663 | ||
4664 | ||
5e2336a0 | 4665 | static const struct file_operations tracing_max_lat_fops = { |
4bf39a94 IM |
4666 | .open = tracing_open_generic, |
4667 | .read = tracing_max_lat_read, | |
4668 | .write = tracing_max_lat_write, | |
b444786f | 4669 | .llseek = generic_file_llseek, |
bc0c38d1 SR |
4670 | }; |
4671 | ||
5e2336a0 | 4672 | static const struct file_operations set_tracer_fops = { |
4bf39a94 IM |
4673 | .open = tracing_open_generic, |
4674 | .read = tracing_set_trace_read, | |
4675 | .write = tracing_set_trace_write, | |
b444786f | 4676 | .llseek = generic_file_llseek, |
bc0c38d1 SR |
4677 | }; |
4678 | ||
5e2336a0 | 4679 | static const struct file_operations tracing_pipe_fops = { |
4bf39a94 | 4680 | .open = tracing_open_pipe, |
2a2cc8f7 | 4681 | .poll = tracing_poll_pipe, |
4bf39a94 | 4682 | .read = tracing_read_pipe, |
3c56819b | 4683 | .splice_read = tracing_splice_read_pipe, |
4bf39a94 | 4684 | .release = tracing_release_pipe, |
b444786f | 4685 | .llseek = no_llseek, |
b3806b43 SR |
4686 | }; |
4687 | ||
5e2336a0 | 4688 | static const struct file_operations tracing_entries_fops = { |
2b6080f2 | 4689 | .open = tracing_open_generic, |
a98a3c3f SR |
4690 | .read = tracing_entries_read, |
4691 | .write = tracing_entries_write, | |
b444786f | 4692 | .llseek = generic_file_llseek, |
a98a3c3f SR |
4693 | }; |
4694 | ||
f81ab074 VN |
4695 | static const struct file_operations tracing_total_entries_fops = { |
4696 | .open = tracing_open_generic, | |
4697 | .read = tracing_total_entries_read, | |
4698 | .llseek = generic_file_llseek, | |
4699 | }; | |
4700 | ||
4f271a2a VN |
4701 | static const struct file_operations tracing_free_buffer_fops = { |
4702 | .write = tracing_free_buffer_write, | |
4703 | .release = tracing_free_buffer_release, | |
4704 | }; | |
4705 | ||
5e2336a0 | 4706 | static const struct file_operations tracing_mark_fops = { |
43a15386 | 4707 | .open = tracing_open_generic, |
5bf9a1ee | 4708 | .write = tracing_mark_write, |
b444786f | 4709 | .llseek = generic_file_llseek, |
5bf9a1ee PP |
4710 | }; |
4711 | ||
5079f326 | 4712 | static const struct file_operations trace_clock_fops = { |
13f16d20 LZ |
4713 | .open = tracing_clock_open, |
4714 | .read = seq_read, | |
4715 | .llseek = seq_lseek, | |
4716 | .release = single_release, | |
5079f326 Z |
4717 | .write = tracing_clock_write, |
4718 | }; | |
4719 | ||
debdd57f HT |
4720 | #ifdef CONFIG_TRACER_SNAPSHOT |
4721 | static const struct file_operations snapshot_fops = { | |
4722 | .open = tracing_snapshot_open, | |
4723 | .read = seq_read, | |
4724 | .write = tracing_snapshot_write, | |
4725 | .llseek = tracing_seek, | |
2b6080f2 | 4726 | .release = tracing_snapshot_release, |
debdd57f | 4727 | }; |
debdd57f | 4728 | |
6de58e62 SRRH |
4729 | static const struct file_operations snapshot_raw_fops = { |
4730 | .open = snapshot_raw_open, | |
4731 | .read = tracing_buffers_read, | |
4732 | .release = tracing_buffers_release, | |
4733 | .splice_read = tracing_buffers_splice_read, | |
4734 | .llseek = no_llseek, | |
2cadf913 SR |
4735 | }; |
4736 | ||
6de58e62 SRRH |
4737 | #endif /* CONFIG_TRACER_SNAPSHOT */ |
4738 | ||
2cadf913 SR |
4739 | static int tracing_buffers_open(struct inode *inode, struct file *filp) |
4740 | { | |
2b6080f2 SR |
4741 | struct trace_cpu *tc = inode->i_private; |
4742 | struct trace_array *tr = tc->tr; | |
2cadf913 SR |
4743 | struct ftrace_buffer_info *info; |
4744 | ||
4745 | if (tracing_disabled) | |
4746 | return -ENODEV; | |
4747 | ||
4748 | info = kzalloc(sizeof(*info), GFP_KERNEL); | |
4749 | if (!info) | |
4750 | return -ENOMEM; | |
4751 | ||
a695cb58 SRRH |
4752 | mutex_lock(&trace_types_lock); |
4753 | ||
4754 | tr->ref++; | |
4755 | ||
cc60cdc9 SR |
4756 | info->iter.tr = tr; |
4757 | info->iter.cpu_file = tc->cpu; | |
b627344f | 4758 | info->iter.trace = tr->current_trace; |
12883efb | 4759 | info->iter.trace_buffer = &tr->trace_buffer; |
cc60cdc9 | 4760 | info->spare = NULL; |
2cadf913 | 4761 | /* Force reading ring buffer for first read */ |
cc60cdc9 | 4762 | info->read = (unsigned int)-1; |
2cadf913 SR |
4763 | |
4764 | filp->private_data = info; | |
4765 | ||
a695cb58 SRRH |
4766 | mutex_unlock(&trace_types_lock); |
4767 | ||
d1e7e02f | 4768 | return nonseekable_open(inode, filp); |
2cadf913 SR |
4769 | } |
4770 | ||
cc60cdc9 SR |
4771 | static unsigned int |
4772 | tracing_buffers_poll(struct file *filp, poll_table *poll_table) | |
4773 | { | |
4774 | struct ftrace_buffer_info *info = filp->private_data; | |
4775 | struct trace_iterator *iter = &info->iter; | |
4776 | ||
4777 | return trace_poll(iter, filp, poll_table); | |
4778 | } | |
4779 | ||
2cadf913 SR |
4780 | static ssize_t |
4781 | tracing_buffers_read(struct file *filp, char __user *ubuf, | |
4782 | size_t count, loff_t *ppos) | |
4783 | { | |
4784 | struct ftrace_buffer_info *info = filp->private_data; | |
cc60cdc9 | 4785 | struct trace_iterator *iter = &info->iter; |
2cadf913 | 4786 | ssize_t ret; |
6de58e62 | 4787 | ssize_t size; |
2cadf913 | 4788 | |
2dc5d12b SR |
4789 | if (!count) |
4790 | return 0; | |
4791 | ||
6de58e62 SRRH |
4792 | mutex_lock(&trace_types_lock); |
4793 | ||
4794 | #ifdef CONFIG_TRACER_MAX_TRACE | |
4795 | if (iter->snapshot && iter->tr->current_trace->use_max_tr) { | |
4796 | size = -EBUSY; | |
4797 | goto out_unlock; | |
4798 | } | |
4799 | #endif | |
4800 | ||
ddd538f3 | 4801 | if (!info->spare) |
12883efb SRRH |
4802 | info->spare = ring_buffer_alloc_read_page(iter->trace_buffer->buffer, |
4803 | iter->cpu_file); | |
6de58e62 | 4804 | size = -ENOMEM; |
ddd538f3 | 4805 | if (!info->spare) |
6de58e62 | 4806 | goto out_unlock; |
ddd538f3 | 4807 | |
2cadf913 SR |
4808 | /* Do we have previous read data to read? */ |
4809 | if (info->read < PAGE_SIZE) | |
4810 | goto read; | |
4811 | ||
b627344f | 4812 | again: |
cc60cdc9 | 4813 | trace_access_lock(iter->cpu_file); |
12883efb | 4814 | ret = ring_buffer_read_page(iter->trace_buffer->buffer, |
2cadf913 SR |
4815 | &info->spare, |
4816 | count, | |
cc60cdc9 SR |
4817 | iter->cpu_file, 0); |
4818 | trace_access_unlock(iter->cpu_file); | |
2cadf913 | 4819 | |
b627344f SR |
4820 | if (ret < 0) { |
4821 | if (trace_empty(iter)) { | |
6de58e62 SRRH |
4822 | if ((filp->f_flags & O_NONBLOCK)) { |
4823 | size = -EAGAIN; | |
4824 | goto out_unlock; | |
4825 | } | |
4826 | mutex_unlock(&trace_types_lock); | |
b627344f | 4827 | iter->trace->wait_pipe(iter); |
6de58e62 SRRH |
4828 | mutex_lock(&trace_types_lock); |
4829 | if (signal_pending(current)) { | |
4830 | size = -EINTR; | |
4831 | goto out_unlock; | |
4832 | } | |
b627344f SR |
4833 | goto again; |
4834 | } | |
6de58e62 SRRH |
4835 | size = 0; |
4836 | goto out_unlock; | |
b627344f | 4837 | } |
436fc280 | 4838 | |
436fc280 | 4839 | info->read = 0; |
b627344f | 4840 | read: |
2cadf913 SR |
4841 | size = PAGE_SIZE - info->read; |
4842 | if (size > count) | |
4843 | size = count; | |
4844 | ||
4845 | ret = copy_to_user(ubuf, info->spare + info->read, size); | |
6de58e62 SRRH |
4846 | if (ret == size) { |
4847 | size = -EFAULT; | |
4848 | goto out_unlock; | |
4849 | } | |
2dc5d12b SR |
4850 | size -= ret; |
4851 | ||
2cadf913 SR |
4852 | *ppos += size; |
4853 | info->read += size; | |
4854 | ||
6de58e62 SRRH |
4855 | out_unlock: |
4856 | mutex_unlock(&trace_types_lock); | |
4857 | ||
2cadf913 SR |
4858 | return size; |
4859 | } | |
4860 | ||
4861 | static int tracing_buffers_release(struct inode *inode, struct file *file) | |
4862 | { | |
4863 | struct ftrace_buffer_info *info = file->private_data; | |
cc60cdc9 | 4864 | struct trace_iterator *iter = &info->iter; |
2cadf913 | 4865 | |
a695cb58 SRRH |
4866 | mutex_lock(&trace_types_lock); |
4867 | ||
4868 | WARN_ON(!iter->tr->ref); | |
4869 | iter->tr->ref--; | |
2cadf913 | 4870 | |
ddd538f3 | 4871 | if (info->spare) |
12883efb | 4872 | ring_buffer_free_read_page(iter->trace_buffer->buffer, info->spare); |
2cadf913 SR |
4873 | kfree(info); |
4874 | ||
a695cb58 SRRH |
4875 | mutex_unlock(&trace_types_lock); |
4876 | ||
2cadf913 SR |
4877 | return 0; |
4878 | } | |
4879 | ||
4880 | struct buffer_ref { | |
4881 | struct ring_buffer *buffer; | |
4882 | void *page; | |
4883 | int ref; | |
4884 | }; | |
4885 | ||
4886 | static void buffer_pipe_buf_release(struct pipe_inode_info *pipe, | |
4887 | struct pipe_buffer *buf) | |
4888 | { | |
4889 | struct buffer_ref *ref = (struct buffer_ref *)buf->private; | |
4890 | ||
4891 | if (--ref->ref) | |
4892 | return; | |
4893 | ||
4894 | ring_buffer_free_read_page(ref->buffer, ref->page); | |
4895 | kfree(ref); | |
4896 | buf->private = 0; | |
4897 | } | |
4898 | ||
2cadf913 SR |
4899 | static void buffer_pipe_buf_get(struct pipe_inode_info *pipe, |
4900 | struct pipe_buffer *buf) | |
4901 | { | |
4902 | struct buffer_ref *ref = (struct buffer_ref *)buf->private; | |
4903 | ||
4904 | ref->ref++; | |
4905 | } | |
4906 | ||
4907 | /* Pipe buffer operations for a buffer. */ | |
28dfef8f | 4908 | static const struct pipe_buf_operations buffer_pipe_buf_ops = { |
2cadf913 SR |
4909 | .can_merge = 0, |
4910 | .map = generic_pipe_buf_map, | |
4911 | .unmap = generic_pipe_buf_unmap, | |
4912 | .confirm = generic_pipe_buf_confirm, | |
4913 | .release = buffer_pipe_buf_release, | |
d55cb6cf | 4914 | .steal = generic_pipe_buf_steal, |
2cadf913 SR |
4915 | .get = buffer_pipe_buf_get, |
4916 | }; | |
4917 | ||
4918 | /* | |
4919 | * Callback from splice_to_pipe(), if we need to release some pages | |
4920 | * at the end of the spd in case we error'ed out in filling the pipe. | |
4921 | */ | |
4922 | static void buffer_spd_release(struct splice_pipe_desc *spd, unsigned int i) | |
4923 | { | |
4924 | struct buffer_ref *ref = | |
4925 | (struct buffer_ref *)spd->partial[i].private; | |
4926 | ||
4927 | if (--ref->ref) | |
4928 | return; | |
4929 | ||
4930 | ring_buffer_free_read_page(ref->buffer, ref->page); | |
4931 | kfree(ref); | |
4932 | spd->partial[i].private = 0; | |
4933 | } | |
4934 | ||
4935 | static ssize_t | |
4936 | tracing_buffers_splice_read(struct file *file, loff_t *ppos, | |
4937 | struct pipe_inode_info *pipe, size_t len, | |
4938 | unsigned int flags) | |
4939 | { | |
4940 | struct ftrace_buffer_info *info = file->private_data; | |
cc60cdc9 | 4941 | struct trace_iterator *iter = &info->iter; |
35f3d14d JA |
4942 | struct partial_page partial_def[PIPE_DEF_BUFFERS]; |
4943 | struct page *pages_def[PIPE_DEF_BUFFERS]; | |
2cadf913 | 4944 | struct splice_pipe_desc spd = { |
35f3d14d JA |
4945 | .pages = pages_def, |
4946 | .partial = partial_def, | |
047fe360 | 4947 | .nr_pages_max = PIPE_DEF_BUFFERS, |
2cadf913 SR |
4948 | .flags = flags, |
4949 | .ops = &buffer_pipe_buf_ops, | |
4950 | .spd_release = buffer_spd_release, | |
4951 | }; | |
4952 | struct buffer_ref *ref; | |
93459c6c | 4953 | int entries, size, i; |
6de58e62 | 4954 | ssize_t ret; |
2cadf913 | 4955 | |
6de58e62 SRRH |
4956 | mutex_lock(&trace_types_lock); |
4957 | ||
4958 | #ifdef CONFIG_TRACER_MAX_TRACE | |
4959 | if (iter->snapshot && iter->tr->current_trace->use_max_tr) { | |
4960 | ret = -EBUSY; | |
4961 | goto out; | |
4962 | } | |
4963 | #endif | |
4964 | ||
4965 | if (splice_grow_spd(pipe, &spd)) { | |
4966 | ret = -ENOMEM; | |
4967 | goto out; | |
4968 | } | |
35f3d14d | 4969 | |
93cfb3c9 | 4970 | if (*ppos & (PAGE_SIZE - 1)) { |
35f3d14d JA |
4971 | ret = -EINVAL; |
4972 | goto out; | |
93cfb3c9 LJ |
4973 | } |
4974 | ||
4975 | if (len & (PAGE_SIZE - 1)) { | |
35f3d14d JA |
4976 | if (len < PAGE_SIZE) { |
4977 | ret = -EINVAL; | |
4978 | goto out; | |
4979 | } | |
93cfb3c9 LJ |
4980 | len &= PAGE_MASK; |
4981 | } | |
4982 | ||
cc60cdc9 SR |
4983 | again: |
4984 | trace_access_lock(iter->cpu_file); | |
12883efb | 4985 | entries = ring_buffer_entries_cpu(iter->trace_buffer->buffer, iter->cpu_file); |
93459c6c | 4986 | |
35f3d14d | 4987 | for (i = 0; i < pipe->buffers && len && entries; i++, len -= PAGE_SIZE) { |
2cadf913 SR |
4988 | struct page *page; |
4989 | int r; | |
4990 | ||
4991 | ref = kzalloc(sizeof(*ref), GFP_KERNEL); | |
4992 | if (!ref) | |
4993 | break; | |
4994 | ||
7267fa68 | 4995 | ref->ref = 1; |
12883efb | 4996 | ref->buffer = iter->trace_buffer->buffer; |
cc60cdc9 | 4997 | ref->page = ring_buffer_alloc_read_page(ref->buffer, iter->cpu_file); |
2cadf913 SR |
4998 | if (!ref->page) { |
4999 | kfree(ref); | |
5000 | break; | |
5001 | } | |
5002 | ||
5003 | r = ring_buffer_read_page(ref->buffer, &ref->page, | |
cc60cdc9 | 5004 | len, iter->cpu_file, 1); |
2cadf913 | 5005 | if (r < 0) { |
7ea59064 | 5006 | ring_buffer_free_read_page(ref->buffer, ref->page); |
2cadf913 SR |
5007 | kfree(ref); |
5008 | break; | |
5009 | } | |
5010 | ||
5011 | /* | |
5012 | * zero out any left over data, this is going to | |
5013 | * user land. | |
5014 | */ | |
5015 | size = ring_buffer_page_len(ref->page); | |
5016 | if (size < PAGE_SIZE) | |
5017 | memset(ref->page + size, 0, PAGE_SIZE - size); | |
5018 | ||
5019 | page = virt_to_page(ref->page); | |
5020 | ||
5021 | spd.pages[i] = page; | |
5022 | spd.partial[i].len = PAGE_SIZE; | |
5023 | spd.partial[i].offset = 0; | |
5024 | spd.partial[i].private = (unsigned long)ref; | |
5025 | spd.nr_pages++; | |
93cfb3c9 | 5026 | *ppos += PAGE_SIZE; |
93459c6c | 5027 | |
12883efb | 5028 | entries = ring_buffer_entries_cpu(iter->trace_buffer->buffer, iter->cpu_file); |
2cadf913 SR |
5029 | } |
5030 | ||
cc60cdc9 | 5031 | trace_access_unlock(iter->cpu_file); |
2cadf913 SR |
5032 | spd.nr_pages = i; |
5033 | ||
5034 | /* did we read anything? */ | |
5035 | if (!spd.nr_pages) { | |
cc60cdc9 | 5036 | if ((file->f_flags & O_NONBLOCK) || (flags & SPLICE_F_NONBLOCK)) { |
2cadf913 | 5037 | ret = -EAGAIN; |
cc60cdc9 SR |
5038 | goto out; |
5039 | } | |
6de58e62 | 5040 | mutex_unlock(&trace_types_lock); |
b627344f | 5041 | iter->trace->wait_pipe(iter); |
6de58e62 | 5042 | mutex_lock(&trace_types_lock); |
cc60cdc9 SR |
5043 | if (signal_pending(current)) { |
5044 | ret = -EINTR; | |
5045 | goto out; | |
5046 | } | |
5047 | goto again; | |
2cadf913 SR |
5048 | } |
5049 | ||
5050 | ret = splice_to_pipe(pipe, &spd); | |
047fe360 | 5051 | splice_shrink_spd(&spd); |
35f3d14d | 5052 | out: |
6de58e62 SRRH |
5053 | mutex_unlock(&trace_types_lock); |
5054 | ||
2cadf913 SR |
5055 | return ret; |
5056 | } | |
5057 | ||
5058 | static const struct file_operations tracing_buffers_fops = { | |
5059 | .open = tracing_buffers_open, | |
5060 | .read = tracing_buffers_read, | |
cc60cdc9 | 5061 | .poll = tracing_buffers_poll, |
2cadf913 SR |
5062 | .release = tracing_buffers_release, |
5063 | .splice_read = tracing_buffers_splice_read, | |
5064 | .llseek = no_llseek, | |
5065 | }; | |
5066 | ||
c8d77183 SR |
5067 | static ssize_t |
5068 | tracing_stats_read(struct file *filp, char __user *ubuf, | |
5069 | size_t count, loff_t *ppos) | |
5070 | { | |
2b6080f2 SR |
5071 | struct trace_cpu *tc = filp->private_data; |
5072 | struct trace_array *tr = tc->tr; | |
12883efb | 5073 | struct trace_buffer *trace_buf = &tr->trace_buffer; |
c8d77183 SR |
5074 | struct trace_seq *s; |
5075 | unsigned long cnt; | |
c64e148a VN |
5076 | unsigned long long t; |
5077 | unsigned long usec_rem; | |
2b6080f2 | 5078 | int cpu = tc->cpu; |
c8d77183 | 5079 | |
e4f2d10f | 5080 | s = kmalloc(sizeof(*s), GFP_KERNEL); |
c8d77183 | 5081 | if (!s) |
a646365c | 5082 | return -ENOMEM; |
c8d77183 SR |
5083 | |
5084 | trace_seq_init(s); | |
5085 | ||
12883efb | 5086 | cnt = ring_buffer_entries_cpu(trace_buf->buffer, cpu); |
c8d77183 SR |
5087 | trace_seq_printf(s, "entries: %ld\n", cnt); |
5088 | ||
12883efb | 5089 | cnt = ring_buffer_overrun_cpu(trace_buf->buffer, cpu); |
c8d77183 SR |
5090 | trace_seq_printf(s, "overrun: %ld\n", cnt); |
5091 | ||
12883efb | 5092 | cnt = ring_buffer_commit_overrun_cpu(trace_buf->buffer, cpu); |
c8d77183 SR |
5093 | trace_seq_printf(s, "commit overrun: %ld\n", cnt); |
5094 | ||
12883efb | 5095 | cnt = ring_buffer_bytes_cpu(trace_buf->buffer, cpu); |
c64e148a VN |
5096 | trace_seq_printf(s, "bytes: %ld\n", cnt); |
5097 | ||
11043d8b YY |
5098 | if (trace_clocks[trace_clock_id].in_ns) { |
5099 | /* local or global for trace_clock */ | |
12883efb | 5100 | t = ns2usecs(ring_buffer_oldest_event_ts(trace_buf->buffer, cpu)); |
11043d8b YY |
5101 | usec_rem = do_div(t, USEC_PER_SEC); |
5102 | trace_seq_printf(s, "oldest event ts: %5llu.%06lu\n", | |
5103 | t, usec_rem); | |
5104 | ||
12883efb | 5105 | t = ns2usecs(ring_buffer_time_stamp(trace_buf->buffer, cpu)); |
11043d8b YY |
5106 | usec_rem = do_div(t, USEC_PER_SEC); |
5107 | trace_seq_printf(s, "now ts: %5llu.%06lu\n", t, usec_rem); | |
5108 | } else { | |
5109 | /* counter or tsc mode for trace_clock */ | |
5110 | trace_seq_printf(s, "oldest event ts: %llu\n", | |
12883efb | 5111 | ring_buffer_oldest_event_ts(trace_buf->buffer, cpu)); |
c64e148a | 5112 | |
11043d8b | 5113 | trace_seq_printf(s, "now ts: %llu\n", |
12883efb | 5114 | ring_buffer_time_stamp(trace_buf->buffer, cpu)); |
11043d8b | 5115 | } |
c64e148a | 5116 | |
12883efb | 5117 | cnt = ring_buffer_dropped_events_cpu(trace_buf->buffer, cpu); |
884bfe89 SP |
5118 | trace_seq_printf(s, "dropped events: %ld\n", cnt); |
5119 | ||
12883efb | 5120 | cnt = ring_buffer_read_events_cpu(trace_buf->buffer, cpu); |
ad964704 SRRH |
5121 | trace_seq_printf(s, "read events: %ld\n", cnt); |
5122 | ||
c8d77183 SR |
5123 | count = simple_read_from_buffer(ubuf, count, ppos, s->buffer, s->len); |
5124 | ||
5125 | kfree(s); | |
5126 | ||
5127 | return count; | |
5128 | } | |
5129 | ||
5130 | static const struct file_operations tracing_stats_fops = { | |
5131 | .open = tracing_open_generic, | |
5132 | .read = tracing_stats_read, | |
b444786f | 5133 | .llseek = generic_file_llseek, |
c8d77183 SR |
5134 | }; |
5135 | ||
bc0c38d1 SR |
5136 | #ifdef CONFIG_DYNAMIC_FTRACE |
5137 | ||
b807c3d0 SR |
5138 | int __weak ftrace_arch_read_dyn_info(char *buf, int size) |
5139 | { | |
5140 | return 0; | |
5141 | } | |
5142 | ||
bc0c38d1 | 5143 | static ssize_t |
b807c3d0 | 5144 | tracing_read_dyn_info(struct file *filp, char __user *ubuf, |
bc0c38d1 SR |
5145 | size_t cnt, loff_t *ppos) |
5146 | { | |
a26a2a27 SR |
5147 | static char ftrace_dyn_info_buffer[1024]; |
5148 | static DEFINE_MUTEX(dyn_info_mutex); | |
bc0c38d1 | 5149 | unsigned long *p = filp->private_data; |
b807c3d0 | 5150 | char *buf = ftrace_dyn_info_buffer; |
a26a2a27 | 5151 | int size = ARRAY_SIZE(ftrace_dyn_info_buffer); |
bc0c38d1 SR |
5152 | int r; |
5153 | ||
b807c3d0 SR |
5154 | mutex_lock(&dyn_info_mutex); |
5155 | r = sprintf(buf, "%ld ", *p); | |
4bf39a94 | 5156 | |
a26a2a27 | 5157 | r += ftrace_arch_read_dyn_info(buf+r, (size-1)-r); |
b807c3d0 SR |
5158 | buf[r++] = '\n'; |
5159 | ||
5160 | r = simple_read_from_buffer(ubuf, cnt, ppos, buf, r); | |
5161 | ||
5162 | mutex_unlock(&dyn_info_mutex); | |
5163 | ||
5164 | return r; | |
bc0c38d1 SR |
5165 | } |
5166 | ||
5e2336a0 | 5167 | static const struct file_operations tracing_dyn_info_fops = { |
4bf39a94 | 5168 | .open = tracing_open_generic, |
b807c3d0 | 5169 | .read = tracing_read_dyn_info, |
b444786f | 5170 | .llseek = generic_file_llseek, |
bc0c38d1 | 5171 | }; |
77fd5c15 | 5172 | #endif /* CONFIG_DYNAMIC_FTRACE */ |
bc0c38d1 | 5173 | |
77fd5c15 SRRH |
5174 | #if defined(CONFIG_TRACER_SNAPSHOT) && defined(CONFIG_DYNAMIC_FTRACE) |
5175 | static void | |
5176 | ftrace_snapshot(unsigned long ip, unsigned long parent_ip, void **data) | |
5177 | { | |
5178 | tracing_snapshot(); | |
5179 | } | |
bc0c38d1 | 5180 | |
77fd5c15 SRRH |
5181 | static void |
5182 | ftrace_count_snapshot(unsigned long ip, unsigned long parent_ip, void **data) | |
bc0c38d1 | 5183 | { |
77fd5c15 SRRH |
5184 | unsigned long *count = (long *)data; |
5185 | ||
5186 | if (!*count) | |
5187 | return; | |
bc0c38d1 | 5188 | |
77fd5c15 SRRH |
5189 | if (*count != -1) |
5190 | (*count)--; | |
5191 | ||
5192 | tracing_snapshot(); | |
5193 | } | |
5194 | ||
5195 | static int | |
5196 | ftrace_snapshot_print(struct seq_file *m, unsigned long ip, | |
5197 | struct ftrace_probe_ops *ops, void *data) | |
5198 | { | |
5199 | long count = (long)data; | |
5200 | ||
5201 | seq_printf(m, "%ps:", (void *)ip); | |
5202 | ||
5203 | seq_printf(m, "snapshot"); | |
5204 | ||
5205 | if (count == -1) | |
5206 | seq_printf(m, ":unlimited\n"); | |
5207 | else | |
5208 | seq_printf(m, ":count=%ld\n", count); | |
5209 | ||
5210 | return 0; | |
5211 | } | |
5212 | ||
5213 | static struct ftrace_probe_ops snapshot_probe_ops = { | |
5214 | .func = ftrace_snapshot, | |
5215 | .print = ftrace_snapshot_print, | |
5216 | }; | |
5217 | ||
5218 | static struct ftrace_probe_ops snapshot_count_probe_ops = { | |
5219 | .func = ftrace_count_snapshot, | |
5220 | .print = ftrace_snapshot_print, | |
5221 | }; | |
5222 | ||
5223 | static int | |
5224 | ftrace_trace_snapshot_callback(struct ftrace_hash *hash, | |
5225 | char *glob, char *cmd, char *param, int enable) | |
5226 | { | |
5227 | struct ftrace_probe_ops *ops; | |
5228 | void *count = (void *)-1; | |
5229 | char *number; | |
5230 | int ret; | |
5231 | ||
5232 | /* hash funcs only work with set_ftrace_filter */ | |
5233 | if (!enable) | |
5234 | return -EINVAL; | |
5235 | ||
5236 | ops = param ? &snapshot_count_probe_ops : &snapshot_probe_ops; | |
5237 | ||
5238 | if (glob[0] == '!') { | |
5239 | unregister_ftrace_function_probe_func(glob+1, ops); | |
5240 | return 0; | |
5241 | } | |
5242 | ||
5243 | if (!param) | |
5244 | goto out_reg; | |
5245 | ||
5246 | number = strsep(¶m, ":"); | |
5247 | ||
5248 | if (!strlen(number)) | |
5249 | goto out_reg; | |
5250 | ||
5251 | /* | |
5252 | * We use the callback data field (which is a pointer) | |
5253 | * as our counter. | |
5254 | */ | |
5255 | ret = kstrtoul(number, 0, (unsigned long *)&count); | |
5256 | if (ret) | |
5257 | return ret; | |
5258 | ||
5259 | out_reg: | |
5260 | ret = register_ftrace_function_probe(glob, ops, count); | |
5261 | ||
5262 | if (ret >= 0) | |
5263 | alloc_snapshot(&global_trace); | |
5264 | ||
5265 | return ret < 0 ? ret : 0; | |
5266 | } | |
5267 | ||
5268 | static struct ftrace_func_command ftrace_snapshot_cmd = { | |
5269 | .name = "snapshot", | |
5270 | .func = ftrace_trace_snapshot_callback, | |
5271 | }; | |
5272 | ||
5273 | static int register_snapshot_cmd(void) | |
5274 | { | |
5275 | return register_ftrace_command(&ftrace_snapshot_cmd); | |
5276 | } | |
5277 | #else | |
5278 | static inline int register_snapshot_cmd(void) { return 0; } | |
5279 | #endif /* defined(CONFIG_TRACER_SNAPSHOT) && defined(CONFIG_DYNAMIC_FTRACE) */ | |
bc0c38d1 | 5280 | |
2b6080f2 | 5281 | struct dentry *tracing_init_dentry_tr(struct trace_array *tr) |
bc0c38d1 | 5282 | { |
2b6080f2 SR |
5283 | if (tr->dir) |
5284 | return tr->dir; | |
bc0c38d1 | 5285 | |
3e1f60b8 FW |
5286 | if (!debugfs_initialized()) |
5287 | return NULL; | |
5288 | ||
2b6080f2 SR |
5289 | if (tr->flags & TRACE_ARRAY_FL_GLOBAL) |
5290 | tr->dir = debugfs_create_dir("tracing", NULL); | |
bc0c38d1 | 5291 | |
687c878a J |
5292 | if (!tr->dir) |
5293 | pr_warn_once("Could not create debugfs directory 'tracing'\n"); | |
bc0c38d1 | 5294 | |
2b6080f2 | 5295 | return tr->dir; |
bc0c38d1 SR |
5296 | } |
5297 | ||
2b6080f2 SR |
5298 | struct dentry *tracing_init_dentry(void) |
5299 | { | |
5300 | return tracing_init_dentry_tr(&global_trace); | |
5301 | } | |
b04cc6b1 | 5302 | |
2b6080f2 | 5303 | static struct dentry *tracing_dentry_percpu(struct trace_array *tr, int cpu) |
b04cc6b1 | 5304 | { |
b04cc6b1 FW |
5305 | struct dentry *d_tracer; |
5306 | ||
2b6080f2 SR |
5307 | if (tr->percpu_dir) |
5308 | return tr->percpu_dir; | |
b04cc6b1 | 5309 | |
2b6080f2 | 5310 | d_tracer = tracing_init_dentry_tr(tr); |
b04cc6b1 FW |
5311 | if (!d_tracer) |
5312 | return NULL; | |
5313 | ||
2b6080f2 | 5314 | tr->percpu_dir = debugfs_create_dir("per_cpu", d_tracer); |
b04cc6b1 | 5315 | |
2b6080f2 SR |
5316 | WARN_ONCE(!tr->percpu_dir, |
5317 | "Could not create debugfs directory 'per_cpu/%d'\n", cpu); | |
b04cc6b1 | 5318 | |
2b6080f2 | 5319 | return tr->percpu_dir; |
b04cc6b1 FW |
5320 | } |
5321 | ||
2b6080f2 SR |
5322 | static void |
5323 | tracing_init_debugfs_percpu(struct trace_array *tr, long cpu) | |
b04cc6b1 | 5324 | { |
12883efb | 5325 | struct trace_array_cpu *data = per_cpu_ptr(tr->trace_buffer.data, cpu); |
2b6080f2 | 5326 | struct dentry *d_percpu = tracing_dentry_percpu(tr, cpu); |
5452af66 | 5327 | struct dentry *d_cpu; |
dd49a38c | 5328 | char cpu_dir[30]; /* 30 characters should be more than enough */ |
b04cc6b1 | 5329 | |
0a3d7ce7 NK |
5330 | if (!d_percpu) |
5331 | return; | |
5332 | ||
dd49a38c | 5333 | snprintf(cpu_dir, 30, "cpu%ld", cpu); |
8656e7a2 FW |
5334 | d_cpu = debugfs_create_dir(cpu_dir, d_percpu); |
5335 | if (!d_cpu) { | |
5336 | pr_warning("Could not create debugfs '%s' entry\n", cpu_dir); | |
5337 | return; | |
5338 | } | |
b04cc6b1 | 5339 | |
8656e7a2 | 5340 | /* per cpu trace_pipe */ |
5452af66 | 5341 | trace_create_file("trace_pipe", 0444, d_cpu, |
2b6080f2 | 5342 | (void *)&data->trace_cpu, &tracing_pipe_fops); |
b04cc6b1 FW |
5343 | |
5344 | /* per cpu trace */ | |
5452af66 | 5345 | trace_create_file("trace", 0644, d_cpu, |
2b6080f2 | 5346 | (void *)&data->trace_cpu, &tracing_fops); |
7f96f93f | 5347 | |
5452af66 | 5348 | trace_create_file("trace_pipe_raw", 0444, d_cpu, |
2b6080f2 | 5349 | (void *)&data->trace_cpu, &tracing_buffers_fops); |
7f96f93f | 5350 | |
c8d77183 | 5351 | trace_create_file("stats", 0444, d_cpu, |
2b6080f2 | 5352 | (void *)&data->trace_cpu, &tracing_stats_fops); |
438ced17 VN |
5353 | |
5354 | trace_create_file("buffer_size_kb", 0444, d_cpu, | |
2b6080f2 | 5355 | (void *)&data->trace_cpu, &tracing_entries_fops); |
f1affcaa SRRH |
5356 | |
5357 | #ifdef CONFIG_TRACER_SNAPSHOT | |
5358 | trace_create_file("snapshot", 0644, d_cpu, | |
5359 | (void *)&data->trace_cpu, &snapshot_fops); | |
6de58e62 SRRH |
5360 | |
5361 | trace_create_file("snapshot_raw", 0444, d_cpu, | |
5362 | (void *)&data->trace_cpu, &snapshot_raw_fops); | |
f1affcaa | 5363 | #endif |
b04cc6b1 FW |
5364 | } |
5365 | ||
60a11774 SR |
5366 | #ifdef CONFIG_FTRACE_SELFTEST |
5367 | /* Let selftest have access to static functions in this file */ | |
5368 | #include "trace_selftest.c" | |
5369 | #endif | |
5370 | ||
577b785f SR |
5371 | struct trace_option_dentry { |
5372 | struct tracer_opt *opt; | |
5373 | struct tracer_flags *flags; | |
2b6080f2 | 5374 | struct trace_array *tr; |
577b785f SR |
5375 | struct dentry *entry; |
5376 | }; | |
5377 | ||
5378 | static ssize_t | |
5379 | trace_options_read(struct file *filp, char __user *ubuf, size_t cnt, | |
5380 | loff_t *ppos) | |
5381 | { | |
5382 | struct trace_option_dentry *topt = filp->private_data; | |
5383 | char *buf; | |
5384 | ||
5385 | if (topt->flags->val & topt->opt->bit) | |
5386 | buf = "1\n"; | |
5387 | else | |
5388 | buf = "0\n"; | |
5389 | ||
5390 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, 2); | |
5391 | } | |
5392 | ||
5393 | static ssize_t | |
5394 | trace_options_write(struct file *filp, const char __user *ubuf, size_t cnt, | |
5395 | loff_t *ppos) | |
5396 | { | |
5397 | struct trace_option_dentry *topt = filp->private_data; | |
5398 | unsigned long val; | |
577b785f SR |
5399 | int ret; |
5400 | ||
22fe9b54 PH |
5401 | ret = kstrtoul_from_user(ubuf, cnt, 10, &val); |
5402 | if (ret) | |
577b785f SR |
5403 | return ret; |
5404 | ||
8d18eaaf LZ |
5405 | if (val != 0 && val != 1) |
5406 | return -EINVAL; | |
577b785f | 5407 | |
8d18eaaf | 5408 | if (!!(topt->flags->val & topt->opt->bit) != val) { |
577b785f | 5409 | mutex_lock(&trace_types_lock); |
2b6080f2 | 5410 | ret = __set_tracer_option(topt->tr->current_trace, topt->flags, |
c757bea9 | 5411 | topt->opt, !val); |
577b785f SR |
5412 | mutex_unlock(&trace_types_lock); |
5413 | if (ret) | |
5414 | return ret; | |
577b785f SR |
5415 | } |
5416 | ||
5417 | *ppos += cnt; | |
5418 | ||
5419 | return cnt; | |
5420 | } | |
5421 | ||
5422 | ||
5423 | static const struct file_operations trace_options_fops = { | |
5424 | .open = tracing_open_generic, | |
5425 | .read = trace_options_read, | |
5426 | .write = trace_options_write, | |
b444786f | 5427 | .llseek = generic_file_llseek, |
577b785f SR |
5428 | }; |
5429 | ||
a8259075 SR |
5430 | static ssize_t |
5431 | trace_options_core_read(struct file *filp, char __user *ubuf, size_t cnt, | |
5432 | loff_t *ppos) | |
5433 | { | |
5434 | long index = (long)filp->private_data; | |
5435 | char *buf; | |
5436 | ||
5437 | if (trace_flags & (1 << index)) | |
5438 | buf = "1\n"; | |
5439 | else | |
5440 | buf = "0\n"; | |
5441 | ||
5442 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, 2); | |
5443 | } | |
5444 | ||
5445 | static ssize_t | |
5446 | trace_options_core_write(struct file *filp, const char __user *ubuf, size_t cnt, | |
5447 | loff_t *ppos) | |
5448 | { | |
2b6080f2 | 5449 | struct trace_array *tr = &global_trace; |
a8259075 | 5450 | long index = (long)filp->private_data; |
a8259075 SR |
5451 | unsigned long val; |
5452 | int ret; | |
5453 | ||
22fe9b54 PH |
5454 | ret = kstrtoul_from_user(ubuf, cnt, 10, &val); |
5455 | if (ret) | |
a8259075 SR |
5456 | return ret; |
5457 | ||
f2d84b65 | 5458 | if (val != 0 && val != 1) |
a8259075 | 5459 | return -EINVAL; |
69d34da2 SRRH |
5460 | |
5461 | mutex_lock(&trace_types_lock); | |
2b6080f2 | 5462 | ret = set_tracer_flag(tr, 1 << index, val); |
69d34da2 | 5463 | mutex_unlock(&trace_types_lock); |
a8259075 | 5464 | |
613f04a0 SRRH |
5465 | if (ret < 0) |
5466 | return ret; | |
5467 | ||
a8259075 SR |
5468 | *ppos += cnt; |
5469 | ||
5470 | return cnt; | |
5471 | } | |
5472 | ||
a8259075 SR |
5473 | static const struct file_operations trace_options_core_fops = { |
5474 | .open = tracing_open_generic, | |
5475 | .read = trace_options_core_read, | |
5476 | .write = trace_options_core_write, | |
b444786f | 5477 | .llseek = generic_file_llseek, |
a8259075 SR |
5478 | }; |
5479 | ||
5452af66 | 5480 | struct dentry *trace_create_file(const char *name, |
f4ae40a6 | 5481 | umode_t mode, |
5452af66 FW |
5482 | struct dentry *parent, |
5483 | void *data, | |
5484 | const struct file_operations *fops) | |
5485 | { | |
5486 | struct dentry *ret; | |
5487 | ||
5488 | ret = debugfs_create_file(name, mode, parent, data, fops); | |
5489 | if (!ret) | |
5490 | pr_warning("Could not create debugfs '%s' entry\n", name); | |
5491 | ||
5492 | return ret; | |
5493 | } | |
5494 | ||
5495 | ||
2b6080f2 | 5496 | static struct dentry *trace_options_init_dentry(struct trace_array *tr) |
a8259075 SR |
5497 | { |
5498 | struct dentry *d_tracer; | |
a8259075 | 5499 | |
2b6080f2 SR |
5500 | if (tr->options) |
5501 | return tr->options; | |
a8259075 | 5502 | |
2b6080f2 | 5503 | d_tracer = tracing_init_dentry_tr(tr); |
a8259075 SR |
5504 | if (!d_tracer) |
5505 | return NULL; | |
5506 | ||
2b6080f2 SR |
5507 | tr->options = debugfs_create_dir("options", d_tracer); |
5508 | if (!tr->options) { | |
a8259075 SR |
5509 | pr_warning("Could not create debugfs directory 'options'\n"); |
5510 | return NULL; | |
5511 | } | |
5512 | ||
2b6080f2 | 5513 | return tr->options; |
a8259075 SR |
5514 | } |
5515 | ||
577b785f | 5516 | static void |
2b6080f2 SR |
5517 | create_trace_option_file(struct trace_array *tr, |
5518 | struct trace_option_dentry *topt, | |
577b785f SR |
5519 | struct tracer_flags *flags, |
5520 | struct tracer_opt *opt) | |
5521 | { | |
5522 | struct dentry *t_options; | |
577b785f | 5523 | |
2b6080f2 | 5524 | t_options = trace_options_init_dentry(tr); |
577b785f SR |
5525 | if (!t_options) |
5526 | return; | |
5527 | ||
5528 | topt->flags = flags; | |
5529 | topt->opt = opt; | |
2b6080f2 | 5530 | topt->tr = tr; |
577b785f | 5531 | |
5452af66 | 5532 | topt->entry = trace_create_file(opt->name, 0644, t_options, topt, |
577b785f SR |
5533 | &trace_options_fops); |
5534 | ||
577b785f SR |
5535 | } |
5536 | ||
5537 | static struct trace_option_dentry * | |
2b6080f2 | 5538 | create_trace_option_files(struct trace_array *tr, struct tracer *tracer) |
577b785f SR |
5539 | { |
5540 | struct trace_option_dentry *topts; | |
5541 | struct tracer_flags *flags; | |
5542 | struct tracer_opt *opts; | |
5543 | int cnt; | |
5544 | ||
5545 | if (!tracer) | |
5546 | return NULL; | |
5547 | ||
5548 | flags = tracer->flags; | |
5549 | ||
5550 | if (!flags || !flags->opts) | |
5551 | return NULL; | |
5552 | ||
5553 | opts = flags->opts; | |
5554 | ||
5555 | for (cnt = 0; opts[cnt].name; cnt++) | |
5556 | ; | |
5557 | ||
0cfe8245 | 5558 | topts = kcalloc(cnt + 1, sizeof(*topts), GFP_KERNEL); |
577b785f SR |
5559 | if (!topts) |
5560 | return NULL; | |
5561 | ||
5562 | for (cnt = 0; opts[cnt].name; cnt++) | |
2b6080f2 | 5563 | create_trace_option_file(tr, &topts[cnt], flags, |
577b785f SR |
5564 | &opts[cnt]); |
5565 | ||
5566 | return topts; | |
5567 | } | |
5568 | ||
5569 | static void | |
5570 | destroy_trace_option_files(struct trace_option_dentry *topts) | |
5571 | { | |
5572 | int cnt; | |
5573 | ||
5574 | if (!topts) | |
5575 | return; | |
5576 | ||
5577 | for (cnt = 0; topts[cnt].opt; cnt++) { | |
5578 | if (topts[cnt].entry) | |
5579 | debugfs_remove(topts[cnt].entry); | |
5580 | } | |
5581 | ||
5582 | kfree(topts); | |
5583 | } | |
5584 | ||
a8259075 | 5585 | static struct dentry * |
2b6080f2 SR |
5586 | create_trace_option_core_file(struct trace_array *tr, |
5587 | const char *option, long index) | |
a8259075 SR |
5588 | { |
5589 | struct dentry *t_options; | |
a8259075 | 5590 | |
2b6080f2 | 5591 | t_options = trace_options_init_dentry(tr); |
a8259075 SR |
5592 | if (!t_options) |
5593 | return NULL; | |
5594 | ||
5452af66 | 5595 | return trace_create_file(option, 0644, t_options, (void *)index, |
a8259075 | 5596 | &trace_options_core_fops); |
a8259075 SR |
5597 | } |
5598 | ||
2b6080f2 | 5599 | static __init void create_trace_options_dir(struct trace_array *tr) |
a8259075 SR |
5600 | { |
5601 | struct dentry *t_options; | |
a8259075 SR |
5602 | int i; |
5603 | ||
2b6080f2 | 5604 | t_options = trace_options_init_dentry(tr); |
a8259075 SR |
5605 | if (!t_options) |
5606 | return; | |
5607 | ||
5452af66 | 5608 | for (i = 0; trace_options[i]; i++) |
2b6080f2 | 5609 | create_trace_option_core_file(tr, trace_options[i], i); |
a8259075 SR |
5610 | } |
5611 | ||
499e5470 SR |
5612 | static ssize_t |
5613 | rb_simple_read(struct file *filp, char __user *ubuf, | |
5614 | size_t cnt, loff_t *ppos) | |
5615 | { | |
348f0fc2 | 5616 | struct trace_array *tr = filp->private_data; |
12883efb | 5617 | struct ring_buffer *buffer = tr->trace_buffer.buffer; |
499e5470 SR |
5618 | char buf[64]; |
5619 | int r; | |
5620 | ||
5621 | if (buffer) | |
5622 | r = ring_buffer_record_is_on(buffer); | |
5623 | else | |
5624 | r = 0; | |
5625 | ||
5626 | r = sprintf(buf, "%d\n", r); | |
5627 | ||
5628 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, r); | |
5629 | } | |
5630 | ||
5631 | static ssize_t | |
5632 | rb_simple_write(struct file *filp, const char __user *ubuf, | |
5633 | size_t cnt, loff_t *ppos) | |
5634 | { | |
348f0fc2 | 5635 | struct trace_array *tr = filp->private_data; |
12883efb | 5636 | struct ring_buffer *buffer = tr->trace_buffer.buffer; |
499e5470 SR |
5637 | unsigned long val; |
5638 | int ret; | |
5639 | ||
5640 | ret = kstrtoul_from_user(ubuf, cnt, 10, &val); | |
5641 | if (ret) | |
5642 | return ret; | |
5643 | ||
5644 | if (buffer) { | |
2df8f8a6 SR |
5645 | mutex_lock(&trace_types_lock); |
5646 | if (val) { | |
499e5470 | 5647 | ring_buffer_record_on(buffer); |
2b6080f2 SR |
5648 | if (tr->current_trace->start) |
5649 | tr->current_trace->start(tr); | |
2df8f8a6 | 5650 | } else { |
499e5470 | 5651 | ring_buffer_record_off(buffer); |
2b6080f2 SR |
5652 | if (tr->current_trace->stop) |
5653 | tr->current_trace->stop(tr); | |
2df8f8a6 SR |
5654 | } |
5655 | mutex_unlock(&trace_types_lock); | |
499e5470 SR |
5656 | } |
5657 | ||
5658 | (*ppos)++; | |
5659 | ||
5660 | return cnt; | |
5661 | } | |
5662 | ||
5663 | static const struct file_operations rb_simple_fops = { | |
5664 | .open = tracing_open_generic, | |
5665 | .read = rb_simple_read, | |
5666 | .write = rb_simple_write, | |
5667 | .llseek = default_llseek, | |
5668 | }; | |
5669 | ||
277ba044 SR |
5670 | struct dentry *trace_instance_dir; |
5671 | ||
5672 | static void | |
5673 | init_tracer_debugfs(struct trace_array *tr, struct dentry *d_tracer); | |
5674 | ||
737223fb SRRH |
5675 | static void init_trace_buffers(struct trace_array *tr, struct trace_buffer *buf) |
5676 | { | |
5677 | int cpu; | |
5678 | ||
5679 | for_each_tracing_cpu(cpu) { | |
5680 | memset(per_cpu_ptr(buf->data, cpu), 0, sizeof(struct trace_array_cpu)); | |
5681 | per_cpu_ptr(buf->data, cpu)->trace_cpu.cpu = cpu; | |
5682 | per_cpu_ptr(buf->data, cpu)->trace_cpu.tr = tr; | |
5683 | } | |
5684 | } | |
5685 | ||
55034cd6 SRRH |
5686 | static int |
5687 | allocate_trace_buffer(struct trace_array *tr, struct trace_buffer *buf, int size) | |
277ba044 SR |
5688 | { |
5689 | enum ring_buffer_flags rb_flags; | |
737223fb SRRH |
5690 | |
5691 | rb_flags = trace_flags & TRACE_ITER_OVERWRITE ? RB_FL_OVERWRITE : 0; | |
5692 | ||
55034cd6 SRRH |
5693 | buf->buffer = ring_buffer_alloc(size, rb_flags); |
5694 | if (!buf->buffer) | |
5695 | return -ENOMEM; | |
737223fb | 5696 | |
55034cd6 SRRH |
5697 | buf->data = alloc_percpu(struct trace_array_cpu); |
5698 | if (!buf->data) { | |
5699 | ring_buffer_free(buf->buffer); | |
5700 | return -ENOMEM; | |
5701 | } | |
737223fb | 5702 | |
55034cd6 | 5703 | init_trace_buffers(tr, buf); |
737223fb SRRH |
5704 | |
5705 | /* Allocate the first page for all buffers */ | |
5706 | set_buffer_entries(&tr->trace_buffer, | |
5707 | ring_buffer_size(tr->trace_buffer.buffer, 0)); | |
5708 | ||
55034cd6 SRRH |
5709 | return 0; |
5710 | } | |
737223fb | 5711 | |
55034cd6 SRRH |
5712 | static int allocate_trace_buffers(struct trace_array *tr, int size) |
5713 | { | |
5714 | int ret; | |
737223fb | 5715 | |
55034cd6 SRRH |
5716 | ret = allocate_trace_buffer(tr, &tr->trace_buffer, size); |
5717 | if (ret) | |
5718 | return ret; | |
737223fb | 5719 | |
55034cd6 SRRH |
5720 | #ifdef CONFIG_TRACER_MAX_TRACE |
5721 | ret = allocate_trace_buffer(tr, &tr->max_buffer, | |
5722 | allocate_snapshot ? size : 1); | |
5723 | if (WARN_ON(ret)) { | |
737223fb | 5724 | ring_buffer_free(tr->trace_buffer.buffer); |
55034cd6 SRRH |
5725 | free_percpu(tr->trace_buffer.data); |
5726 | return -ENOMEM; | |
5727 | } | |
5728 | tr->allocated_snapshot = allocate_snapshot; | |
737223fb | 5729 | |
55034cd6 SRRH |
5730 | /* |
5731 | * Only the top level trace array gets its snapshot allocated | |
5732 | * from the kernel command line. | |
5733 | */ | |
5734 | allocate_snapshot = false; | |
737223fb | 5735 | #endif |
55034cd6 | 5736 | return 0; |
737223fb SRRH |
5737 | } |
5738 | ||
5739 | static int new_instance_create(const char *name) | |
5740 | { | |
277ba044 SR |
5741 | struct trace_array *tr; |
5742 | int ret; | |
277ba044 SR |
5743 | |
5744 | mutex_lock(&trace_types_lock); | |
5745 | ||
5746 | ret = -EEXIST; | |
5747 | list_for_each_entry(tr, &ftrace_trace_arrays, list) { | |
5748 | if (tr->name && strcmp(tr->name, name) == 0) | |
5749 | goto out_unlock; | |
5750 | } | |
5751 | ||
5752 | ret = -ENOMEM; | |
5753 | tr = kzalloc(sizeof(*tr), GFP_KERNEL); | |
5754 | if (!tr) | |
5755 | goto out_unlock; | |
5756 | ||
5757 | tr->name = kstrdup(name, GFP_KERNEL); | |
5758 | if (!tr->name) | |
5759 | goto out_free_tr; | |
5760 | ||
5761 | raw_spin_lock_init(&tr->start_lock); | |
5762 | ||
5763 | tr->current_trace = &nop_trace; | |
5764 | ||
5765 | INIT_LIST_HEAD(&tr->systems); | |
5766 | INIT_LIST_HEAD(&tr->events); | |
5767 | ||
737223fb | 5768 | if (allocate_trace_buffers(tr, trace_buf_size) < 0) |
277ba044 SR |
5769 | goto out_free_tr; |
5770 | ||
277ba044 SR |
5771 | /* Holder for file callbacks */ |
5772 | tr->trace_cpu.cpu = RING_BUFFER_ALL_CPUS; | |
5773 | tr->trace_cpu.tr = tr; | |
5774 | ||
5775 | tr->dir = debugfs_create_dir(name, trace_instance_dir); | |
5776 | if (!tr->dir) | |
5777 | goto out_free_tr; | |
5778 | ||
5779 | ret = event_trace_add_tracer(tr->dir, tr); | |
5780 | if (ret) | |
5781 | goto out_free_tr; | |
5782 | ||
5783 | init_tracer_debugfs(tr, tr->dir); | |
5784 | ||
5785 | list_add(&tr->list, &ftrace_trace_arrays); | |
5786 | ||
5787 | mutex_unlock(&trace_types_lock); | |
5788 | ||
5789 | return 0; | |
5790 | ||
5791 | out_free_tr: | |
12883efb SRRH |
5792 | if (tr->trace_buffer.buffer) |
5793 | ring_buffer_free(tr->trace_buffer.buffer); | |
277ba044 SR |
5794 | kfree(tr->name); |
5795 | kfree(tr); | |
5796 | ||
5797 | out_unlock: | |
5798 | mutex_unlock(&trace_types_lock); | |
5799 | ||
5800 | return ret; | |
5801 | ||
5802 | } | |
5803 | ||
0c8916c3 SR |
5804 | static int instance_delete(const char *name) |
5805 | { | |
5806 | struct trace_array *tr; | |
5807 | int found = 0; | |
5808 | int ret; | |
5809 | ||
5810 | mutex_lock(&trace_types_lock); | |
5811 | ||
5812 | ret = -ENODEV; | |
5813 | list_for_each_entry(tr, &ftrace_trace_arrays, list) { | |
5814 | if (tr->name && strcmp(tr->name, name) == 0) { | |
5815 | found = 1; | |
5816 | break; | |
5817 | } | |
5818 | } | |
5819 | if (!found) | |
5820 | goto out_unlock; | |
5821 | ||
a695cb58 SRRH |
5822 | ret = -EBUSY; |
5823 | if (tr->ref) | |
5824 | goto out_unlock; | |
5825 | ||
0c8916c3 SR |
5826 | list_del(&tr->list); |
5827 | ||
5828 | event_trace_del_tracer(tr); | |
5829 | debugfs_remove_recursive(tr->dir); | |
12883efb SRRH |
5830 | free_percpu(tr->trace_buffer.data); |
5831 | ring_buffer_free(tr->trace_buffer.buffer); | |
0c8916c3 SR |
5832 | |
5833 | kfree(tr->name); | |
5834 | kfree(tr); | |
5835 | ||
5836 | ret = 0; | |
5837 | ||
5838 | out_unlock: | |
5839 | mutex_unlock(&trace_types_lock); | |
5840 | ||
5841 | return ret; | |
5842 | } | |
5843 | ||
277ba044 SR |
5844 | static int instance_mkdir (struct inode *inode, struct dentry *dentry, umode_t mode) |
5845 | { | |
5846 | struct dentry *parent; | |
5847 | int ret; | |
5848 | ||
5849 | /* Paranoid: Make sure the parent is the "instances" directory */ | |
5850 | parent = hlist_entry(inode->i_dentry.first, struct dentry, d_alias); | |
5851 | if (WARN_ON_ONCE(parent != trace_instance_dir)) | |
5852 | return -ENOENT; | |
5853 | ||
5854 | /* | |
5855 | * The inode mutex is locked, but debugfs_create_dir() will also | |
5856 | * take the mutex. As the instances directory can not be destroyed | |
5857 | * or changed in any other way, it is safe to unlock it, and | |
5858 | * let the dentry try. If two users try to make the same dir at | |
5859 | * the same time, then the new_instance_create() will determine the | |
5860 | * winner. | |
5861 | */ | |
5862 | mutex_unlock(&inode->i_mutex); | |
5863 | ||
5864 | ret = new_instance_create(dentry->d_iname); | |
5865 | ||
5866 | mutex_lock(&inode->i_mutex); | |
5867 | ||
5868 | return ret; | |
5869 | } | |
5870 | ||
0c8916c3 SR |
5871 | static int instance_rmdir(struct inode *inode, struct dentry *dentry) |
5872 | { | |
5873 | struct dentry *parent; | |
5874 | int ret; | |
5875 | ||
5876 | /* Paranoid: Make sure the parent is the "instances" directory */ | |
5877 | parent = hlist_entry(inode->i_dentry.first, struct dentry, d_alias); | |
5878 | if (WARN_ON_ONCE(parent != trace_instance_dir)) | |
5879 | return -ENOENT; | |
5880 | ||
5881 | /* The caller did a dget() on dentry */ | |
5882 | mutex_unlock(&dentry->d_inode->i_mutex); | |
5883 | ||
5884 | /* | |
5885 | * The inode mutex is locked, but debugfs_create_dir() will also | |
5886 | * take the mutex. As the instances directory can not be destroyed | |
5887 | * or changed in any other way, it is safe to unlock it, and | |
5888 | * let the dentry try. If two users try to make the same dir at | |
5889 | * the same time, then the instance_delete() will determine the | |
5890 | * winner. | |
5891 | */ | |
5892 | mutex_unlock(&inode->i_mutex); | |
5893 | ||
5894 | ret = instance_delete(dentry->d_iname); | |
5895 | ||
5896 | mutex_lock_nested(&inode->i_mutex, I_MUTEX_PARENT); | |
5897 | mutex_lock(&dentry->d_inode->i_mutex); | |
5898 | ||
5899 | return ret; | |
5900 | } | |
5901 | ||
277ba044 SR |
5902 | static const struct inode_operations instance_dir_inode_operations = { |
5903 | .lookup = simple_lookup, | |
5904 | .mkdir = instance_mkdir, | |
0c8916c3 | 5905 | .rmdir = instance_rmdir, |
277ba044 SR |
5906 | }; |
5907 | ||
5908 | static __init void create_trace_instances(struct dentry *d_tracer) | |
5909 | { | |
5910 | trace_instance_dir = debugfs_create_dir("instances", d_tracer); | |
5911 | if (WARN_ON(!trace_instance_dir)) | |
5912 | return; | |
5913 | ||
5914 | /* Hijack the dir inode operations, to allow mkdir */ | |
5915 | trace_instance_dir->d_inode->i_op = &instance_dir_inode_operations; | |
5916 | } | |
5917 | ||
2b6080f2 SR |
5918 | static void |
5919 | init_tracer_debugfs(struct trace_array *tr, struct dentry *d_tracer) | |
5920 | { | |
121aaee7 | 5921 | int cpu; |
2b6080f2 SR |
5922 | |
5923 | trace_create_file("trace_options", 0644, d_tracer, | |
5924 | tr, &tracing_iter_fops); | |
5925 | ||
5926 | trace_create_file("trace", 0644, d_tracer, | |
5927 | (void *)&tr->trace_cpu, &tracing_fops); | |
5928 | ||
5929 | trace_create_file("trace_pipe", 0444, d_tracer, | |
5930 | (void *)&tr->trace_cpu, &tracing_pipe_fops); | |
5931 | ||
5932 | trace_create_file("buffer_size_kb", 0644, d_tracer, | |
5933 | (void *)&tr->trace_cpu, &tracing_entries_fops); | |
5934 | ||
5935 | trace_create_file("buffer_total_size_kb", 0444, d_tracer, | |
5936 | tr, &tracing_total_entries_fops); | |
5937 | ||
5938 | trace_create_file("free_buffer", 0644, d_tracer, | |
5939 | tr, &tracing_free_buffer_fops); | |
5940 | ||
5941 | trace_create_file("trace_marker", 0220, d_tracer, | |
5942 | tr, &tracing_mark_fops); | |
5943 | ||
5944 | trace_create_file("trace_clock", 0644, d_tracer, tr, | |
5945 | &trace_clock_fops); | |
5946 | ||
5947 | trace_create_file("tracing_on", 0644, d_tracer, | |
5948 | tr, &rb_simple_fops); | |
ce9bae55 SRRH |
5949 | |
5950 | #ifdef CONFIG_TRACER_SNAPSHOT | |
5951 | trace_create_file("snapshot", 0644, d_tracer, | |
5952 | (void *)&tr->trace_cpu, &snapshot_fops); | |
5953 | #endif | |
121aaee7 SRRH |
5954 | |
5955 | for_each_tracing_cpu(cpu) | |
5956 | tracing_init_debugfs_percpu(tr, cpu); | |
5957 | ||
2b6080f2 SR |
5958 | } |
5959 | ||
b5ad384e | 5960 | static __init int tracer_init_debugfs(void) |
bc0c38d1 SR |
5961 | { |
5962 | struct dentry *d_tracer; | |
bc0c38d1 | 5963 | |
7e53bd42 LJ |
5964 | trace_access_lock_init(); |
5965 | ||
bc0c38d1 | 5966 | d_tracer = tracing_init_dentry(); |
ed6f1c99 NK |
5967 | if (!d_tracer) |
5968 | return 0; | |
bc0c38d1 | 5969 | |
2b6080f2 | 5970 | init_tracer_debugfs(&global_trace, d_tracer); |
bc0c38d1 | 5971 | |
5452af66 | 5972 | trace_create_file("tracing_cpumask", 0644, d_tracer, |
2b6080f2 | 5973 | &global_trace, &tracing_cpumask_fops); |
a8259075 | 5974 | |
5452af66 FW |
5975 | trace_create_file("available_tracers", 0444, d_tracer, |
5976 | &global_trace, &show_traces_fops); | |
5977 | ||
339ae5d3 | 5978 | trace_create_file("current_tracer", 0644, d_tracer, |
5452af66 FW |
5979 | &global_trace, &set_tracer_fops); |
5980 | ||
5d4a9dba | 5981 | #ifdef CONFIG_TRACER_MAX_TRACE |
5452af66 FW |
5982 | trace_create_file("tracing_max_latency", 0644, d_tracer, |
5983 | &tracing_max_latency, &tracing_max_lat_fops); | |
0e950173 | 5984 | #endif |
5452af66 FW |
5985 | |
5986 | trace_create_file("tracing_thresh", 0644, d_tracer, | |
5987 | &tracing_thresh, &tracing_max_lat_fops); | |
a8259075 | 5988 | |
339ae5d3 | 5989 | trace_create_file("README", 0444, d_tracer, |
5452af66 FW |
5990 | NULL, &tracing_readme_fops); |
5991 | ||
69abe6a5 AP |
5992 | trace_create_file("saved_cmdlines", 0444, d_tracer, |
5993 | NULL, &tracing_saved_cmdlines_fops); | |
5bf9a1ee | 5994 | |
bc0c38d1 | 5995 | #ifdef CONFIG_DYNAMIC_FTRACE |
5452af66 FW |
5996 | trace_create_file("dyn_ftrace_total_info", 0444, d_tracer, |
5997 | &ftrace_update_tot_cnt, &tracing_dyn_info_fops); | |
bc0c38d1 | 5998 | #endif |
b04cc6b1 | 5999 | |
277ba044 | 6000 | create_trace_instances(d_tracer); |
5452af66 | 6001 | |
2b6080f2 | 6002 | create_trace_options_dir(&global_trace); |
b04cc6b1 | 6003 | |
b5ad384e | 6004 | return 0; |
bc0c38d1 SR |
6005 | } |
6006 | ||
3f5a54e3 SR |
6007 | static int trace_panic_handler(struct notifier_block *this, |
6008 | unsigned long event, void *unused) | |
6009 | { | |
944ac425 | 6010 | if (ftrace_dump_on_oops) |
cecbca96 | 6011 | ftrace_dump(ftrace_dump_on_oops); |
3f5a54e3 SR |
6012 | return NOTIFY_OK; |
6013 | } | |
6014 | ||
6015 | static struct notifier_block trace_panic_notifier = { | |
6016 | .notifier_call = trace_panic_handler, | |
6017 | .next = NULL, | |
6018 | .priority = 150 /* priority: INT_MAX >= x >= 0 */ | |
6019 | }; | |
6020 | ||
6021 | static int trace_die_handler(struct notifier_block *self, | |
6022 | unsigned long val, | |
6023 | void *data) | |
6024 | { | |
6025 | switch (val) { | |
6026 | case DIE_OOPS: | |
944ac425 | 6027 | if (ftrace_dump_on_oops) |
cecbca96 | 6028 | ftrace_dump(ftrace_dump_on_oops); |
3f5a54e3 SR |
6029 | break; |
6030 | default: | |
6031 | break; | |
6032 | } | |
6033 | return NOTIFY_OK; | |
6034 | } | |
6035 | ||
6036 | static struct notifier_block trace_die_notifier = { | |
6037 | .notifier_call = trace_die_handler, | |
6038 | .priority = 200 | |
6039 | }; | |
6040 | ||
6041 | /* | |
6042 | * printk is set to max of 1024, we really don't need it that big. | |
6043 | * Nothing should be printing 1000 characters anyway. | |
6044 | */ | |
6045 | #define TRACE_MAX_PRINT 1000 | |
6046 | ||
6047 | /* | |
6048 | * Define here KERN_TRACE so that we have one place to modify | |
6049 | * it if we decide to change what log level the ftrace dump | |
6050 | * should be at. | |
6051 | */ | |
428aee14 | 6052 | #define KERN_TRACE KERN_EMERG |
3f5a54e3 | 6053 | |
955b61e5 | 6054 | void |
3f5a54e3 SR |
6055 | trace_printk_seq(struct trace_seq *s) |
6056 | { | |
6057 | /* Probably should print a warning here. */ | |
bd6df187 J |
6058 | if (s->len >= TRACE_MAX_PRINT) |
6059 | s->len = TRACE_MAX_PRINT; | |
3f5a54e3 SR |
6060 | |
6061 | /* should be zero ended, but we are paranoid. */ | |
6062 | s->buffer[s->len] = 0; | |
6063 | ||
6064 | printk(KERN_TRACE "%s", s->buffer); | |
6065 | ||
f9520750 | 6066 | trace_seq_init(s); |
3f5a54e3 SR |
6067 | } |
6068 | ||
955b61e5 JW |
6069 | void trace_init_global_iter(struct trace_iterator *iter) |
6070 | { | |
6071 | iter->tr = &global_trace; | |
2b6080f2 | 6072 | iter->trace = iter->tr->current_trace; |
ae3b5093 | 6073 | iter->cpu_file = RING_BUFFER_ALL_CPUS; |
12883efb | 6074 | iter->trace_buffer = &global_trace.trace_buffer; |
955b61e5 JW |
6075 | } |
6076 | ||
7fe70b57 | 6077 | void ftrace_dump(enum ftrace_dump_mode oops_dump_mode) |
3f5a54e3 | 6078 | { |
3f5a54e3 SR |
6079 | /* use static because iter can be a bit big for the stack */ |
6080 | static struct trace_iterator iter; | |
7fe70b57 | 6081 | static atomic_t dump_running; |
cf586b61 | 6082 | unsigned int old_userobj; |
d769041f SR |
6083 | unsigned long flags; |
6084 | int cnt = 0, cpu; | |
3f5a54e3 | 6085 | |
7fe70b57 SRRH |
6086 | /* Only allow one dump user at a time. */ |
6087 | if (atomic_inc_return(&dump_running) != 1) { | |
6088 | atomic_dec(&dump_running); | |
6089 | return; | |
6090 | } | |
3f5a54e3 | 6091 | |
7fe70b57 SRRH |
6092 | /* |
6093 | * Always turn off tracing when we dump. | |
6094 | * We don't need to show trace output of what happens | |
6095 | * between multiple crashes. | |
6096 | * | |
6097 | * If the user does a sysrq-z, then they can re-enable | |
6098 | * tracing with echo 1 > tracing_on. | |
6099 | */ | |
0ee6b6cf | 6100 | tracing_off(); |
cf586b61 | 6101 | |
7fe70b57 | 6102 | local_irq_save(flags); |
3f5a54e3 | 6103 | |
38dbe0b1 | 6104 | /* Simulate the iterator */ |
955b61e5 JW |
6105 | trace_init_global_iter(&iter); |
6106 | ||
d769041f | 6107 | for_each_tracing_cpu(cpu) { |
12883efb | 6108 | atomic_inc(&per_cpu_ptr(iter.tr->trace_buffer.data, cpu)->disabled); |
d769041f SR |
6109 | } |
6110 | ||
cf586b61 FW |
6111 | old_userobj = trace_flags & TRACE_ITER_SYM_USEROBJ; |
6112 | ||
b54d3de9 TE |
6113 | /* don't look at user memory in panic mode */ |
6114 | trace_flags &= ~TRACE_ITER_SYM_USEROBJ; | |
6115 | ||
cecbca96 FW |
6116 | switch (oops_dump_mode) { |
6117 | case DUMP_ALL: | |
ae3b5093 | 6118 | iter.cpu_file = RING_BUFFER_ALL_CPUS; |
cecbca96 FW |
6119 | break; |
6120 | case DUMP_ORIG: | |
6121 | iter.cpu_file = raw_smp_processor_id(); | |
6122 | break; | |
6123 | case DUMP_NONE: | |
6124 | goto out_enable; | |
6125 | default: | |
6126 | printk(KERN_TRACE "Bad dumping mode, switching to all CPUs dump\n"); | |
ae3b5093 | 6127 | iter.cpu_file = RING_BUFFER_ALL_CPUS; |
cecbca96 FW |
6128 | } |
6129 | ||
6130 | printk(KERN_TRACE "Dumping ftrace buffer:\n"); | |
3f5a54e3 | 6131 | |
7fe70b57 SRRH |
6132 | /* Did function tracer already get disabled? */ |
6133 | if (ftrace_is_dead()) { | |
6134 | printk("# WARNING: FUNCTION TRACING IS CORRUPTED\n"); | |
6135 | printk("# MAY BE MISSING FUNCTION EVENTS\n"); | |
6136 | } | |
6137 | ||
3f5a54e3 SR |
6138 | /* |
6139 | * We need to stop all tracing on all CPUS to read the | |
6140 | * the next buffer. This is a bit expensive, but is | |
6141 | * not done often. We fill all what we can read, | |
6142 | * and then release the locks again. | |
6143 | */ | |
6144 | ||
3f5a54e3 SR |
6145 | while (!trace_empty(&iter)) { |
6146 | ||
6147 | if (!cnt) | |
6148 | printk(KERN_TRACE "---------------------------------\n"); | |
6149 | ||
6150 | cnt++; | |
6151 | ||
6152 | /* reset all but tr, trace, and overruns */ | |
6153 | memset(&iter.seq, 0, | |
6154 | sizeof(struct trace_iterator) - | |
6155 | offsetof(struct trace_iterator, seq)); | |
6156 | iter.iter_flags |= TRACE_FILE_LAT_FMT; | |
6157 | iter.pos = -1; | |
6158 | ||
955b61e5 | 6159 | if (trace_find_next_entry_inc(&iter) != NULL) { |
74e7ff8c LJ |
6160 | int ret; |
6161 | ||
6162 | ret = print_trace_line(&iter); | |
6163 | if (ret != TRACE_TYPE_NO_CONSUME) | |
6164 | trace_consume(&iter); | |
3f5a54e3 | 6165 | } |
b892e5c8 | 6166 | touch_nmi_watchdog(); |
3f5a54e3 SR |
6167 | |
6168 | trace_printk_seq(&iter.seq); | |
6169 | } | |
6170 | ||
6171 | if (!cnt) | |
6172 | printk(KERN_TRACE " (ftrace buffer empty)\n"); | |
6173 | else | |
6174 | printk(KERN_TRACE "---------------------------------\n"); | |
6175 | ||
cecbca96 | 6176 | out_enable: |
7fe70b57 | 6177 | trace_flags |= old_userobj; |
cf586b61 | 6178 | |
7fe70b57 SRRH |
6179 | for_each_tracing_cpu(cpu) { |
6180 | atomic_dec(&per_cpu_ptr(iter.trace_buffer->data, cpu)->disabled); | |
cf586b61 | 6181 | } |
7fe70b57 | 6182 | atomic_dec(&dump_running); |
cd891ae0 | 6183 | local_irq_restore(flags); |
3f5a54e3 | 6184 | } |
a8eecf22 | 6185 | EXPORT_SYMBOL_GPL(ftrace_dump); |
cf586b61 | 6186 | |
3928a8a2 | 6187 | __init static int tracer_alloc_buffers(void) |
bc0c38d1 | 6188 | { |
73c5162a | 6189 | int ring_buf_size; |
9e01c1b7 | 6190 | int ret = -ENOMEM; |
4c11d7ae | 6191 | |
750912fa | 6192 | |
9e01c1b7 RR |
6193 | if (!alloc_cpumask_var(&tracing_buffer_mask, GFP_KERNEL)) |
6194 | goto out; | |
6195 | ||
6196 | if (!alloc_cpumask_var(&tracing_cpumask, GFP_KERNEL)) | |
6197 | goto out_free_buffer_mask; | |
4c11d7ae | 6198 | |
07d777fe SR |
6199 | /* Only allocate trace_printk buffers if a trace_printk exists */ |
6200 | if (__stop___trace_bprintk_fmt != __start___trace_bprintk_fmt) | |
81698831 | 6201 | /* Must be called before global_trace.buffer is allocated */ |
07d777fe SR |
6202 | trace_printk_init_buffers(); |
6203 | ||
73c5162a SR |
6204 | /* To save memory, keep the ring buffer size to its minimum */ |
6205 | if (ring_buffer_expanded) | |
6206 | ring_buf_size = trace_buf_size; | |
6207 | else | |
6208 | ring_buf_size = 1; | |
6209 | ||
9e01c1b7 RR |
6210 | cpumask_copy(tracing_buffer_mask, cpu_possible_mask); |
6211 | cpumask_copy(tracing_cpumask, cpu_all_mask); | |
6212 | ||
2b6080f2 SR |
6213 | raw_spin_lock_init(&global_trace.start_lock); |
6214 | ||
9e01c1b7 | 6215 | /* TODO: make the number of buffers hot pluggable with CPUS */ |
737223fb | 6216 | if (allocate_trace_buffers(&global_trace, ring_buf_size) < 0) { |
3928a8a2 SR |
6217 | printk(KERN_ERR "tracer: failed to allocate ring buffer!\n"); |
6218 | WARN_ON(1); | |
9e01c1b7 | 6219 | goto out_free_cpumask; |
4c11d7ae | 6220 | } |
a7603ff4 | 6221 | |
499e5470 SR |
6222 | if (global_trace.buffer_disabled) |
6223 | tracing_off(); | |
4c11d7ae | 6224 | |
bc0c38d1 SR |
6225 | trace_init_cmdlines(); |
6226 | ||
ca164318 SRRH |
6227 | /* |
6228 | * register_tracer() might reference current_trace, so it | |
6229 | * needs to be set before we register anything. This is | |
6230 | * just a bootstrap of current_trace anyway. | |
6231 | */ | |
2b6080f2 SR |
6232 | global_trace.current_trace = &nop_trace; |
6233 | ||
ca164318 SRRH |
6234 | register_tracer(&nop_trace); |
6235 | ||
60a11774 SR |
6236 | /* All seems OK, enable tracing */ |
6237 | tracing_disabled = 0; | |
3928a8a2 | 6238 | |
3f5a54e3 SR |
6239 | atomic_notifier_chain_register(&panic_notifier_list, |
6240 | &trace_panic_notifier); | |
6241 | ||
6242 | register_die_notifier(&trace_die_notifier); | |
2fc1dfbe | 6243 | |
ae63b31e SR |
6244 | global_trace.flags = TRACE_ARRAY_FL_GLOBAL; |
6245 | ||
2b6080f2 SR |
6246 | /* Holder for file callbacks */ |
6247 | global_trace.trace_cpu.cpu = RING_BUFFER_ALL_CPUS; | |
6248 | global_trace.trace_cpu.tr = &global_trace; | |
6249 | ||
ae63b31e SR |
6250 | INIT_LIST_HEAD(&global_trace.systems); |
6251 | INIT_LIST_HEAD(&global_trace.events); | |
6252 | list_add(&global_trace.list, &ftrace_trace_arrays); | |
6253 | ||
7bcfaf54 SR |
6254 | while (trace_boot_options) { |
6255 | char *option; | |
6256 | ||
6257 | option = strsep(&trace_boot_options, ","); | |
2b6080f2 | 6258 | trace_set_options(&global_trace, option); |
7bcfaf54 SR |
6259 | } |
6260 | ||
77fd5c15 SRRH |
6261 | register_snapshot_cmd(); |
6262 | ||
2fc1dfbe | 6263 | return 0; |
3f5a54e3 | 6264 | |
9e01c1b7 | 6265 | out_free_cpumask: |
12883efb SRRH |
6266 | free_percpu(global_trace.trace_buffer.data); |
6267 | #ifdef CONFIG_TRACER_MAX_TRACE | |
6268 | free_percpu(global_trace.max_buffer.data); | |
6269 | #endif | |
9e01c1b7 RR |
6270 | free_cpumask_var(tracing_cpumask); |
6271 | out_free_buffer_mask: | |
6272 | free_cpumask_var(tracing_buffer_mask); | |
6273 | out: | |
6274 | return ret; | |
bc0c38d1 | 6275 | } |
b2821ae6 SR |
6276 | |
6277 | __init static int clear_boot_tracer(void) | |
6278 | { | |
6279 | /* | |
6280 | * The default tracer at boot buffer is an init section. | |
6281 | * This function is called in lateinit. If we did not | |
6282 | * find the boot tracer, then clear it out, to prevent | |
6283 | * later registration from accessing the buffer that is | |
6284 | * about to be freed. | |
6285 | */ | |
6286 | if (!default_bootup_tracer) | |
6287 | return 0; | |
6288 | ||
6289 | printk(KERN_INFO "ftrace bootup tracer '%s' not registered.\n", | |
6290 | default_bootup_tracer); | |
6291 | default_bootup_tracer = NULL; | |
6292 | ||
6293 | return 0; | |
6294 | } | |
6295 | ||
b5ad384e FW |
6296 | early_initcall(tracer_alloc_buffers); |
6297 | fs_initcall(tracer_init_debugfs); | |
b2821ae6 | 6298 | late_initcall(clear_boot_tracer); |