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Commit | Line | Data |
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bc0c38d1 SR |
1 | /* |
2 | * ring buffer based function tracer | |
3 | * | |
4 | * Copyright (C) 2007-2008 Steven Rostedt <srostedt@redhat.com> | |
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 | |
12 | * Copyright (C) 2004 William Lee Irwin III | |
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> | |
405f5571 | 20 | #include <linux/smp_lock.h> |
3f5a54e3 | 21 | #include <linux/notifier.h> |
2cadf913 | 22 | #include <linux/irqflags.h> |
bc0c38d1 | 23 | #include <linux/debugfs.h> |
4c11d7ae | 24 | #include <linux/pagemap.h> |
bc0c38d1 SR |
25 | #include <linux/hardirq.h> |
26 | #include <linux/linkage.h> | |
27 | #include <linux/uaccess.h> | |
2cadf913 | 28 | #include <linux/kprobes.h> |
bc0c38d1 SR |
29 | #include <linux/ftrace.h> |
30 | #include <linux/module.h> | |
31 | #include <linux/percpu.h> | |
2cadf913 | 32 | #include <linux/splice.h> |
3f5a54e3 | 33 | #include <linux/kdebug.h> |
5f0c6c03 | 34 | #include <linux/string.h> |
7e53bd42 | 35 | #include <linux/rwsem.h> |
5a0e3ad6 | 36 | #include <linux/slab.h> |
bc0c38d1 SR |
37 | #include <linux/ctype.h> |
38 | #include <linux/init.h> | |
2a2cc8f7 | 39 | #include <linux/poll.h> |
bc0c38d1 | 40 | #include <linux/fs.h> |
86387f7e | 41 | |
bc0c38d1 | 42 | #include "trace.h" |
f0868d1e | 43 | #include "trace_output.h" |
bc0c38d1 | 44 | |
3928a8a2 SR |
45 | #define TRACE_BUFFER_FLAGS (RB_FL_OVERWRITE) |
46 | ||
73c5162a SR |
47 | /* |
48 | * On boot up, the ring buffer is set to the minimum size, so that | |
49 | * we do not waste memory on systems that are not using tracing. | |
50 | */ | |
020e5f85 | 51 | int ring_buffer_expanded; |
73c5162a | 52 | |
8e1b82e0 FW |
53 | /* |
54 | * We need to change this state when a selftest is running. | |
ff32504f FW |
55 | * A selftest will lurk into the ring-buffer to count the |
56 | * entries inserted during the selftest although some concurrent | |
5e1607a0 | 57 | * insertions into the ring-buffer such as trace_printk could occurred |
ff32504f FW |
58 | * at the same time, giving false positive or negative results. |
59 | */ | |
8e1b82e0 | 60 | static bool __read_mostly tracing_selftest_running; |
ff32504f | 61 | |
b2821ae6 SR |
62 | /* |
63 | * If a tracer is running, we do not want to run SELFTEST. | |
64 | */ | |
020e5f85 | 65 | bool __read_mostly tracing_selftest_disabled; |
b2821ae6 | 66 | |
adf9f195 FW |
67 | /* For tracers that don't implement custom flags */ |
68 | static struct tracer_opt dummy_tracer_opt[] = { | |
69 | { } | |
70 | }; | |
71 | ||
72 | static struct tracer_flags dummy_tracer_flags = { | |
73 | .val = 0, | |
74 | .opts = dummy_tracer_opt | |
75 | }; | |
76 | ||
77 | static int dummy_set_flag(u32 old_flags, u32 bit, int set) | |
78 | { | |
79 | return 0; | |
80 | } | |
0f048701 SR |
81 | |
82 | /* | |
83 | * Kill all tracing for good (never come back). | |
84 | * It is initialized to 1 but will turn to zero if the initialization | |
85 | * of the tracer is successful. But that is the only place that sets | |
86 | * this back to zero. | |
87 | */ | |
4fd27358 | 88 | static int tracing_disabled = 1; |
0f048701 | 89 | |
9288f99a | 90 | DEFINE_PER_CPU(int, ftrace_cpu_disabled); |
d769041f SR |
91 | |
92 | static inline void ftrace_disable_cpu(void) | |
93 | { | |
94 | preempt_disable(); | |
dd17c8f7 | 95 | __this_cpu_inc(ftrace_cpu_disabled); |
d769041f SR |
96 | } |
97 | ||
98 | static inline void ftrace_enable_cpu(void) | |
99 | { | |
dd17c8f7 | 100 | __this_cpu_dec(ftrace_cpu_disabled); |
d769041f SR |
101 | preempt_enable(); |
102 | } | |
103 | ||
9e01c1b7 | 104 | static cpumask_var_t __read_mostly tracing_buffer_mask; |
ab46428c SR |
105 | |
106 | #define for_each_tracing_cpu(cpu) \ | |
9e01c1b7 | 107 | for_each_cpu(cpu, tracing_buffer_mask) |
ab46428c | 108 | |
944ac425 SR |
109 | /* |
110 | * ftrace_dump_on_oops - variable to dump ftrace buffer on oops | |
111 | * | |
112 | * If there is an oops (or kernel panic) and the ftrace_dump_on_oops | |
113 | * is set, then ftrace_dump is called. This will output the contents | |
114 | * of the ftrace buffers to the console. This is very useful for | |
115 | * capturing traces that lead to crashes and outputing it to a | |
116 | * serial console. | |
117 | * | |
118 | * It is default off, but you can enable it with either specifying | |
119 | * "ftrace_dump_on_oops" in the kernel command line, or setting | |
cecbca96 FW |
120 | * /proc/sys/kernel/ftrace_dump_on_oops |
121 | * Set 1 if you want to dump buffers of all CPUs | |
122 | * Set 2 if you want to dump the buffer of the CPU that triggered oops | |
944ac425 | 123 | */ |
cecbca96 FW |
124 | |
125 | enum ftrace_dump_mode ftrace_dump_on_oops; | |
944ac425 | 126 | |
b2821ae6 SR |
127 | static int tracing_set_tracer(const char *buf); |
128 | ||
ee6c2c1b LZ |
129 | #define MAX_TRACER_SIZE 100 |
130 | static char bootup_tracer_buf[MAX_TRACER_SIZE] __initdata; | |
b2821ae6 | 131 | static char *default_bootup_tracer; |
d9e54076 | 132 | |
1beee96b | 133 | static int __init set_cmdline_ftrace(char *str) |
d9e54076 | 134 | { |
ee6c2c1b | 135 | strncpy(bootup_tracer_buf, str, MAX_TRACER_SIZE); |
b2821ae6 | 136 | default_bootup_tracer = bootup_tracer_buf; |
73c5162a SR |
137 | /* We are using ftrace early, expand it */ |
138 | ring_buffer_expanded = 1; | |
d9e54076 PZ |
139 | return 1; |
140 | } | |
1beee96b | 141 | __setup("ftrace=", set_cmdline_ftrace); |
d9e54076 | 142 | |
944ac425 SR |
143 | static int __init set_ftrace_dump_on_oops(char *str) |
144 | { | |
cecbca96 FW |
145 | if (*str++ != '=' || !*str) { |
146 | ftrace_dump_on_oops = DUMP_ALL; | |
147 | return 1; | |
148 | } | |
149 | ||
150 | if (!strcmp("orig_cpu", str)) { | |
151 | ftrace_dump_on_oops = DUMP_ORIG; | |
152 | return 1; | |
153 | } | |
154 | ||
155 | return 0; | |
944ac425 SR |
156 | } |
157 | __setup("ftrace_dump_on_oops", set_ftrace_dump_on_oops); | |
60a11774 | 158 | |
cf8e3474 | 159 | unsigned long long ns2usecs(cycle_t nsec) |
bc0c38d1 SR |
160 | { |
161 | nsec += 500; | |
162 | do_div(nsec, 1000); | |
163 | return nsec; | |
164 | } | |
165 | ||
4fcdae83 SR |
166 | /* |
167 | * The global_trace is the descriptor that holds the tracing | |
168 | * buffers for the live tracing. For each CPU, it contains | |
169 | * a link list of pages that will store trace entries. The | |
170 | * page descriptor of the pages in the memory is used to hold | |
171 | * the link list by linking the lru item in the page descriptor | |
172 | * to each of the pages in the buffer per CPU. | |
173 | * | |
174 | * For each active CPU there is a data field that holds the | |
175 | * pages for the buffer for that CPU. Each CPU has the same number | |
176 | * of pages allocated for its buffer. | |
177 | */ | |
bc0c38d1 SR |
178 | static struct trace_array global_trace; |
179 | ||
180 | static DEFINE_PER_CPU(struct trace_array_cpu, global_trace_cpu); | |
181 | ||
e77405ad SR |
182 | int filter_current_check_discard(struct ring_buffer *buffer, |
183 | struct ftrace_event_call *call, void *rec, | |
eb02ce01 TZ |
184 | struct ring_buffer_event *event) |
185 | { | |
e77405ad | 186 | return filter_check_discard(call, rec, buffer, event); |
eb02ce01 | 187 | } |
17c873ec | 188 | EXPORT_SYMBOL_GPL(filter_current_check_discard); |
eb02ce01 | 189 | |
37886f6a SR |
190 | cycle_t ftrace_now(int cpu) |
191 | { | |
192 | u64 ts; | |
193 | ||
194 | /* Early boot up does not have a buffer yet */ | |
195 | if (!global_trace.buffer) | |
196 | return trace_clock_local(); | |
197 | ||
198 | ts = ring_buffer_time_stamp(global_trace.buffer, cpu); | |
199 | ring_buffer_normalize_time_stamp(global_trace.buffer, cpu, &ts); | |
200 | ||
201 | return ts; | |
202 | } | |
bc0c38d1 | 203 | |
4fcdae83 SR |
204 | /* |
205 | * The max_tr is used to snapshot the global_trace when a maximum | |
206 | * latency is reached. Some tracers will use this to store a maximum | |
207 | * trace while it continues examining live traces. | |
208 | * | |
209 | * The buffers for the max_tr are set up the same as the global_trace. | |
210 | * When a snapshot is taken, the link list of the max_tr is swapped | |
211 | * with the link list of the global_trace and the buffers are reset for | |
212 | * the global_trace so the tracing can continue. | |
213 | */ | |
bc0c38d1 SR |
214 | static struct trace_array max_tr; |
215 | ||
9705f69e | 216 | static DEFINE_PER_CPU(struct trace_array_cpu, max_tr_data); |
bc0c38d1 | 217 | |
4fcdae83 | 218 | /* tracer_enabled is used to toggle activation of a tracer */ |
26994ead | 219 | static int tracer_enabled = 1; |
4fcdae83 | 220 | |
9036990d SR |
221 | /** |
222 | * tracing_is_enabled - return tracer_enabled status | |
223 | * | |
224 | * This function is used by other tracers to know the status | |
225 | * of the tracer_enabled flag. Tracers may use this function | |
226 | * to know if it should enable their features when starting | |
227 | * up. See irqsoff tracer for an example (start_irqsoff_tracer). | |
228 | */ | |
229 | int tracing_is_enabled(void) | |
230 | { | |
231 | return tracer_enabled; | |
232 | } | |
233 | ||
4fcdae83 | 234 | /* |
3928a8a2 SR |
235 | * trace_buf_size is the size in bytes that is allocated |
236 | * for a buffer. Note, the number of bytes is always rounded | |
237 | * to page size. | |
3f5a54e3 SR |
238 | * |
239 | * This number is purposely set to a low number of 16384. | |
240 | * If the dump on oops happens, it will be much appreciated | |
241 | * to not have to wait for all that output. Anyway this can be | |
242 | * boot time and run time configurable. | |
4fcdae83 | 243 | */ |
3928a8a2 | 244 | #define TRACE_BUF_SIZE_DEFAULT 1441792UL /* 16384 * 88 (sizeof(entry)) */ |
3f5a54e3 | 245 | |
3928a8a2 | 246 | static unsigned long trace_buf_size = TRACE_BUF_SIZE_DEFAULT; |
bc0c38d1 | 247 | |
4fcdae83 | 248 | /* trace_types holds a link list of available tracers. */ |
bc0c38d1 | 249 | static struct tracer *trace_types __read_mostly; |
4fcdae83 SR |
250 | |
251 | /* current_trace points to the tracer that is currently active */ | |
bc0c38d1 | 252 | static struct tracer *current_trace __read_mostly; |
4fcdae83 | 253 | |
4fcdae83 SR |
254 | /* |
255 | * trace_types_lock is used to protect the trace_types list. | |
4fcdae83 | 256 | */ |
bc0c38d1 | 257 | static DEFINE_MUTEX(trace_types_lock); |
4fcdae83 | 258 | |
7e53bd42 LJ |
259 | /* |
260 | * serialize the access of the ring buffer | |
261 | * | |
262 | * ring buffer serializes readers, but it is low level protection. | |
263 | * The validity of the events (which returns by ring_buffer_peek() ..etc) | |
264 | * are not protected by ring buffer. | |
265 | * | |
266 | * The content of events may become garbage if we allow other process consumes | |
267 | * these events concurrently: | |
268 | * A) the page of the consumed events may become a normal page | |
269 | * (not reader page) in ring buffer, and this page will be rewrited | |
270 | * by events producer. | |
271 | * B) The page of the consumed events may become a page for splice_read, | |
272 | * and this page will be returned to system. | |
273 | * | |
274 | * These primitives allow multi process access to different cpu ring buffer | |
275 | * concurrently. | |
276 | * | |
277 | * These primitives don't distinguish read-only and read-consume access. | |
278 | * Multi read-only access are also serialized. | |
279 | */ | |
280 | ||
281 | #ifdef CONFIG_SMP | |
282 | static DECLARE_RWSEM(all_cpu_access_lock); | |
283 | static DEFINE_PER_CPU(struct mutex, cpu_access_lock); | |
284 | ||
285 | static inline void trace_access_lock(int cpu) | |
286 | { | |
287 | if (cpu == TRACE_PIPE_ALL_CPU) { | |
288 | /* gain it for accessing the whole ring buffer. */ | |
289 | down_write(&all_cpu_access_lock); | |
290 | } else { | |
291 | /* gain it for accessing a cpu ring buffer. */ | |
292 | ||
293 | /* Firstly block other trace_access_lock(TRACE_PIPE_ALL_CPU). */ | |
294 | down_read(&all_cpu_access_lock); | |
295 | ||
296 | /* Secondly block other access to this @cpu ring buffer. */ | |
297 | mutex_lock(&per_cpu(cpu_access_lock, cpu)); | |
298 | } | |
299 | } | |
300 | ||
301 | static inline void trace_access_unlock(int cpu) | |
302 | { | |
303 | if (cpu == TRACE_PIPE_ALL_CPU) { | |
304 | up_write(&all_cpu_access_lock); | |
305 | } else { | |
306 | mutex_unlock(&per_cpu(cpu_access_lock, cpu)); | |
307 | up_read(&all_cpu_access_lock); | |
308 | } | |
309 | } | |
310 | ||
311 | static inline void trace_access_lock_init(void) | |
312 | { | |
313 | int cpu; | |
314 | ||
315 | for_each_possible_cpu(cpu) | |
316 | mutex_init(&per_cpu(cpu_access_lock, cpu)); | |
317 | } | |
318 | ||
319 | #else | |
320 | ||
321 | static DEFINE_MUTEX(access_lock); | |
322 | ||
323 | static inline void trace_access_lock(int cpu) | |
324 | { | |
325 | (void)cpu; | |
326 | mutex_lock(&access_lock); | |
327 | } | |
328 | ||
329 | static inline void trace_access_unlock(int cpu) | |
330 | { | |
331 | (void)cpu; | |
332 | mutex_unlock(&access_lock); | |
333 | } | |
334 | ||
335 | static inline void trace_access_lock_init(void) | |
336 | { | |
337 | } | |
338 | ||
339 | #endif | |
340 | ||
4fcdae83 | 341 | /* trace_wait is a waitqueue for tasks blocked on trace_poll */ |
4e655519 IM |
342 | static DECLARE_WAIT_QUEUE_HEAD(trace_wait); |
343 | ||
ee6bce52 | 344 | /* trace_flags holds trace_options default values */ |
12ef7d44 | 345 | unsigned long trace_flags = TRACE_ITER_PRINT_PARENT | TRACE_ITER_PRINTK | |
a2a16d6a SR |
346 | TRACE_ITER_ANNOTATE | TRACE_ITER_CONTEXT_INFO | TRACE_ITER_SLEEP_TIME | |
347 | TRACE_ITER_GRAPH_TIME; | |
4e655519 | 348 | |
b8de7bd1 SR |
349 | static int trace_stop_count; |
350 | static DEFINE_SPINLOCK(tracing_start_lock); | |
351 | ||
4fcdae83 SR |
352 | /** |
353 | * trace_wake_up - wake up tasks waiting for trace input | |
354 | * | |
355 | * Simply wakes up any task that is blocked on the trace_wait | |
356 | * queue. These is used with trace_poll for tasks polling the trace. | |
357 | */ | |
4e655519 IM |
358 | void trace_wake_up(void) |
359 | { | |
89f19f04 AM |
360 | int cpu; |
361 | ||
362 | if (trace_flags & TRACE_ITER_BLOCK) | |
363 | return; | |
017730c1 IM |
364 | /* |
365 | * The runqueue_is_locked() can fail, but this is the best we | |
366 | * have for now: | |
367 | */ | |
89f19f04 AM |
368 | cpu = get_cpu(); |
369 | if (!runqueue_is_locked(cpu)) | |
4e655519 | 370 | wake_up(&trace_wait); |
89f19f04 | 371 | put_cpu(); |
4e655519 | 372 | } |
bc0c38d1 | 373 | |
3928a8a2 | 374 | static int __init set_buf_size(char *str) |
bc0c38d1 | 375 | { |
3928a8a2 | 376 | unsigned long buf_size; |
c6caeeb1 | 377 | |
bc0c38d1 SR |
378 | if (!str) |
379 | return 0; | |
9d612bef | 380 | buf_size = memparse(str, &str); |
c6caeeb1 | 381 | /* nr_entries can not be zero */ |
9d612bef | 382 | if (buf_size == 0) |
c6caeeb1 | 383 | return 0; |
3928a8a2 | 384 | trace_buf_size = buf_size; |
bc0c38d1 SR |
385 | return 1; |
386 | } | |
3928a8a2 | 387 | __setup("trace_buf_size=", set_buf_size); |
bc0c38d1 | 388 | |
0e950173 TB |
389 | static int __init set_tracing_thresh(char *str) |
390 | { | |
391 | unsigned long threshhold; | |
392 | int ret; | |
393 | ||
394 | if (!str) | |
395 | return 0; | |
396 | ret = strict_strtoul(str, 0, &threshhold); | |
397 | if (ret < 0) | |
398 | return 0; | |
399 | tracing_thresh = threshhold * 1000; | |
400 | return 1; | |
401 | } | |
402 | __setup("tracing_thresh=", set_tracing_thresh); | |
403 | ||
57f50be1 SR |
404 | unsigned long nsecs_to_usecs(unsigned long nsecs) |
405 | { | |
406 | return nsecs / 1000; | |
407 | } | |
408 | ||
4fcdae83 | 409 | /* These must match the bit postions in trace_iterator_flags */ |
bc0c38d1 SR |
410 | static const char *trace_options[] = { |
411 | "print-parent", | |
412 | "sym-offset", | |
413 | "sym-addr", | |
414 | "verbose", | |
f9896bf3 | 415 | "raw", |
5e3ca0ec | 416 | "hex", |
cb0f12aa | 417 | "bin", |
2a2cc8f7 | 418 | "block", |
86387f7e | 419 | "stacktrace", |
5e1607a0 | 420 | "trace_printk", |
b2a866f9 | 421 | "ftrace_preempt", |
9f029e83 | 422 | "branch", |
12ef7d44 | 423 | "annotate", |
02b67518 | 424 | "userstacktrace", |
b54d3de9 | 425 | "sym-userobj", |
66896a85 | 426 | "printk-msg-only", |
c4a8e8be | 427 | "context-info", |
c032ef64 | 428 | "latency-format", |
be6f164a | 429 | "sleep-time", |
a2a16d6a | 430 | "graph-time", |
bc0c38d1 SR |
431 | NULL |
432 | }; | |
433 | ||
5079f326 Z |
434 | static struct { |
435 | u64 (*func)(void); | |
436 | const char *name; | |
437 | } trace_clocks[] = { | |
438 | { trace_clock_local, "local" }, | |
439 | { trace_clock_global, "global" }, | |
440 | }; | |
441 | ||
442 | int trace_clock_id; | |
443 | ||
b63f39ea | 444 | /* |
445 | * trace_parser_get_init - gets the buffer for trace parser | |
446 | */ | |
447 | int trace_parser_get_init(struct trace_parser *parser, int size) | |
448 | { | |
449 | memset(parser, 0, sizeof(*parser)); | |
450 | ||
451 | parser->buffer = kmalloc(size, GFP_KERNEL); | |
452 | if (!parser->buffer) | |
453 | return 1; | |
454 | ||
455 | parser->size = size; | |
456 | return 0; | |
457 | } | |
458 | ||
459 | /* | |
460 | * trace_parser_put - frees the buffer for trace parser | |
461 | */ | |
462 | void trace_parser_put(struct trace_parser *parser) | |
463 | { | |
464 | kfree(parser->buffer); | |
465 | } | |
466 | ||
467 | /* | |
468 | * trace_get_user - reads the user input string separated by space | |
469 | * (matched by isspace(ch)) | |
470 | * | |
471 | * For each string found the 'struct trace_parser' is updated, | |
472 | * and the function returns. | |
473 | * | |
474 | * Returns number of bytes read. | |
475 | * | |
476 | * See kernel/trace/trace.h for 'struct trace_parser' details. | |
477 | */ | |
478 | int trace_get_user(struct trace_parser *parser, const char __user *ubuf, | |
479 | size_t cnt, loff_t *ppos) | |
480 | { | |
481 | char ch; | |
482 | size_t read = 0; | |
483 | ssize_t ret; | |
484 | ||
485 | if (!*ppos) | |
486 | trace_parser_clear(parser); | |
487 | ||
488 | ret = get_user(ch, ubuf++); | |
489 | if (ret) | |
490 | goto out; | |
491 | ||
492 | read++; | |
493 | cnt--; | |
494 | ||
495 | /* | |
496 | * The parser is not finished with the last write, | |
497 | * continue reading the user input without skipping spaces. | |
498 | */ | |
499 | if (!parser->cont) { | |
500 | /* skip white space */ | |
501 | while (cnt && isspace(ch)) { | |
502 | ret = get_user(ch, ubuf++); | |
503 | if (ret) | |
504 | goto out; | |
505 | read++; | |
506 | cnt--; | |
507 | } | |
508 | ||
509 | /* only spaces were written */ | |
510 | if (isspace(ch)) { | |
511 | *ppos += read; | |
512 | ret = read; | |
513 | goto out; | |
514 | } | |
515 | ||
516 | parser->idx = 0; | |
517 | } | |
518 | ||
519 | /* read the non-space input */ | |
520 | while (cnt && !isspace(ch)) { | |
3c235a33 | 521 | if (parser->idx < parser->size - 1) |
b63f39ea | 522 | parser->buffer[parser->idx++] = ch; |
523 | else { | |
524 | ret = -EINVAL; | |
525 | goto out; | |
526 | } | |
527 | ret = get_user(ch, ubuf++); | |
528 | if (ret) | |
529 | goto out; | |
530 | read++; | |
531 | cnt--; | |
532 | } | |
533 | ||
534 | /* We either got finished input or we have to wait for another call. */ | |
535 | if (isspace(ch)) { | |
536 | parser->buffer[parser->idx] = 0; | |
537 | parser->cont = false; | |
538 | } else { | |
539 | parser->cont = true; | |
540 | parser->buffer[parser->idx++] = ch; | |
541 | } | |
542 | ||
543 | *ppos += read; | |
544 | ret = read; | |
545 | ||
546 | out: | |
547 | return ret; | |
548 | } | |
549 | ||
6c6c2796 PP |
550 | ssize_t trace_seq_to_user(struct trace_seq *s, char __user *ubuf, size_t cnt) |
551 | { | |
552 | int len; | |
553 | int ret; | |
554 | ||
2dc5d12b SR |
555 | if (!cnt) |
556 | return 0; | |
557 | ||
6c6c2796 PP |
558 | if (s->len <= s->readpos) |
559 | return -EBUSY; | |
560 | ||
561 | len = s->len - s->readpos; | |
562 | if (cnt > len) | |
563 | cnt = len; | |
564 | ret = copy_to_user(ubuf, s->buffer + s->readpos, cnt); | |
2dc5d12b | 565 | if (ret == cnt) |
6c6c2796 PP |
566 | return -EFAULT; |
567 | ||
2dc5d12b SR |
568 | cnt -= ret; |
569 | ||
e74da523 | 570 | s->readpos += cnt; |
6c6c2796 | 571 | return cnt; |
214023c3 SR |
572 | } |
573 | ||
b8b94265 | 574 | static ssize_t trace_seq_to_buffer(struct trace_seq *s, void *buf, size_t cnt) |
3c56819b EGM |
575 | { |
576 | int len; | |
577 | void *ret; | |
578 | ||
579 | if (s->len <= s->readpos) | |
580 | return -EBUSY; | |
581 | ||
582 | len = s->len - s->readpos; | |
583 | if (cnt > len) | |
584 | cnt = len; | |
585 | ret = memcpy(buf, s->buffer + s->readpos, cnt); | |
586 | if (!ret) | |
587 | return -EFAULT; | |
588 | ||
e74da523 | 589 | s->readpos += cnt; |
3c56819b EGM |
590 | return cnt; |
591 | } | |
592 | ||
5d4a9dba SR |
593 | /* |
594 | * ftrace_max_lock is used to protect the swapping of buffers | |
595 | * when taking a max snapshot. The buffers themselves are | |
596 | * protected by per_cpu spinlocks. But the action of the swap | |
597 | * needs its own lock. | |
598 | * | |
445c8951 | 599 | * This is defined as a arch_spinlock_t in order to help |
5d4a9dba SR |
600 | * with performance when lockdep debugging is enabled. |
601 | * | |
602 | * It is also used in other places outside the update_max_tr | |
603 | * so it needs to be defined outside of the | |
604 | * CONFIG_TRACER_MAX_TRACE. | |
605 | */ | |
445c8951 | 606 | static arch_spinlock_t ftrace_max_lock = |
edc35bd7 | 607 | (arch_spinlock_t)__ARCH_SPIN_LOCK_UNLOCKED; |
5d4a9dba | 608 | |
0e950173 TB |
609 | unsigned long __read_mostly tracing_thresh; |
610 | ||
5d4a9dba SR |
611 | #ifdef CONFIG_TRACER_MAX_TRACE |
612 | unsigned long __read_mostly tracing_max_latency; | |
5d4a9dba SR |
613 | |
614 | /* | |
615 | * Copy the new maximum trace into the separate maximum-trace | |
616 | * structure. (this way the maximum trace is permanently saved, | |
617 | * for later retrieval via /sys/kernel/debug/tracing/latency_trace) | |
618 | */ | |
619 | static void | |
620 | __update_max_tr(struct trace_array *tr, struct task_struct *tsk, int cpu) | |
621 | { | |
622 | struct trace_array_cpu *data = tr->data[cpu]; | |
1acaa1b2 | 623 | struct trace_array_cpu *max_data; |
5d4a9dba SR |
624 | |
625 | max_tr.cpu = cpu; | |
626 | max_tr.time_start = data->preempt_timestamp; | |
627 | ||
8248ac05 SR |
628 | max_data = max_tr.data[cpu]; |
629 | max_data->saved_latency = tracing_max_latency; | |
630 | max_data->critical_start = data->critical_start; | |
631 | max_data->critical_end = data->critical_end; | |
5d4a9dba | 632 | |
1acaa1b2 | 633 | memcpy(max_data->comm, tsk->comm, TASK_COMM_LEN); |
8248ac05 SR |
634 | max_data->pid = tsk->pid; |
635 | max_data->uid = task_uid(tsk); | |
636 | max_data->nice = tsk->static_prio - 20 - MAX_RT_PRIO; | |
637 | max_data->policy = tsk->policy; | |
638 | max_data->rt_priority = tsk->rt_priority; | |
5d4a9dba SR |
639 | |
640 | /* record this tasks comm */ | |
641 | tracing_record_cmdline(tsk); | |
642 | } | |
643 | ||
4fcdae83 SR |
644 | /** |
645 | * update_max_tr - snapshot all trace buffers from global_trace to max_tr | |
646 | * @tr: tracer | |
647 | * @tsk: the task with the latency | |
648 | * @cpu: The cpu that initiated the trace. | |
649 | * | |
650 | * Flip the buffers between the @tr and the max_tr and record information | |
651 | * about which task was the cause of this latency. | |
652 | */ | |
e309b41d | 653 | void |
bc0c38d1 SR |
654 | update_max_tr(struct trace_array *tr, struct task_struct *tsk, int cpu) |
655 | { | |
3928a8a2 | 656 | struct ring_buffer *buf = tr->buffer; |
bc0c38d1 | 657 | |
b8de7bd1 SR |
658 | if (trace_stop_count) |
659 | return; | |
660 | ||
4c11d7ae | 661 | WARN_ON_ONCE(!irqs_disabled()); |
0199c4e6 | 662 | arch_spin_lock(&ftrace_max_lock); |
3928a8a2 SR |
663 | |
664 | tr->buffer = max_tr.buffer; | |
665 | max_tr.buffer = buf; | |
666 | ||
bc0c38d1 | 667 | __update_max_tr(tr, tsk, cpu); |
0199c4e6 | 668 | arch_spin_unlock(&ftrace_max_lock); |
bc0c38d1 SR |
669 | } |
670 | ||
671 | /** | |
672 | * update_max_tr_single - only copy one trace over, and reset the rest | |
673 | * @tr - tracer | |
674 | * @tsk - task with the latency | |
675 | * @cpu - the cpu of the buffer to copy. | |
4fcdae83 SR |
676 | * |
677 | * Flip the trace of a single CPU buffer between the @tr and the max_tr. | |
bc0c38d1 | 678 | */ |
e309b41d | 679 | void |
bc0c38d1 SR |
680 | update_max_tr_single(struct trace_array *tr, struct task_struct *tsk, int cpu) |
681 | { | |
3928a8a2 | 682 | int ret; |
bc0c38d1 | 683 | |
b8de7bd1 SR |
684 | if (trace_stop_count) |
685 | return; | |
686 | ||
4c11d7ae | 687 | WARN_ON_ONCE(!irqs_disabled()); |
0199c4e6 | 688 | arch_spin_lock(&ftrace_max_lock); |
bc0c38d1 | 689 | |
d769041f SR |
690 | ftrace_disable_cpu(); |
691 | ||
3928a8a2 SR |
692 | ret = ring_buffer_swap_cpu(max_tr.buffer, tr->buffer, cpu); |
693 | ||
e8165dbb SR |
694 | if (ret == -EBUSY) { |
695 | /* | |
696 | * We failed to swap the buffer due to a commit taking | |
697 | * place on this CPU. We fail to record, but we reset | |
698 | * the max trace buffer (no one writes directly to it) | |
699 | * and flag that it failed. | |
700 | */ | |
701 | trace_array_printk(&max_tr, _THIS_IP_, | |
702 | "Failed to swap buffers due to commit in progress\n"); | |
703 | } | |
704 | ||
d769041f SR |
705 | ftrace_enable_cpu(); |
706 | ||
e8165dbb | 707 | WARN_ON_ONCE(ret && ret != -EAGAIN && ret != -EBUSY); |
bc0c38d1 SR |
708 | |
709 | __update_max_tr(tr, tsk, cpu); | |
0199c4e6 | 710 | arch_spin_unlock(&ftrace_max_lock); |
bc0c38d1 | 711 | } |
5d4a9dba | 712 | #endif /* CONFIG_TRACER_MAX_TRACE */ |
bc0c38d1 | 713 | |
4fcdae83 SR |
714 | /** |
715 | * register_tracer - register a tracer with the ftrace system. | |
716 | * @type - the plugin for the tracer | |
717 | * | |
718 | * Register a new plugin tracer. | |
719 | */ | |
bc0c38d1 | 720 | int register_tracer(struct tracer *type) |
e7669b8e HE |
721 | __releases(kernel_lock) |
722 | __acquires(kernel_lock) | |
bc0c38d1 SR |
723 | { |
724 | struct tracer *t; | |
bc0c38d1 SR |
725 | int ret = 0; |
726 | ||
727 | if (!type->name) { | |
728 | pr_info("Tracer must have a name\n"); | |
729 | return -1; | |
730 | } | |
731 | ||
ee6c2c1b LZ |
732 | if (strlen(type->name) > MAX_TRACER_SIZE) { |
733 | pr_info("Tracer has a name longer than %d\n", MAX_TRACER_SIZE); | |
734 | return -1; | |
735 | } | |
736 | ||
86fa2f60 IM |
737 | /* |
738 | * When this gets called we hold the BKL which means that | |
739 | * preemption is disabled. Various trace selftests however | |
740 | * need to disable and enable preemption for successful tests. | |
741 | * So we drop the BKL here and grab it after the tests again. | |
742 | */ | |
743 | unlock_kernel(); | |
bc0c38d1 | 744 | mutex_lock(&trace_types_lock); |
86fa2f60 | 745 | |
8e1b82e0 FW |
746 | tracing_selftest_running = true; |
747 | ||
bc0c38d1 SR |
748 | for (t = trace_types; t; t = t->next) { |
749 | if (strcmp(type->name, t->name) == 0) { | |
750 | /* already found */ | |
ee6c2c1b | 751 | pr_info("Tracer %s already registered\n", |
bc0c38d1 SR |
752 | type->name); |
753 | ret = -1; | |
754 | goto out; | |
755 | } | |
756 | } | |
757 | ||
adf9f195 FW |
758 | if (!type->set_flag) |
759 | type->set_flag = &dummy_set_flag; | |
760 | if (!type->flags) | |
761 | type->flags = &dummy_tracer_flags; | |
762 | else | |
763 | if (!type->flags->opts) | |
764 | type->flags->opts = dummy_tracer_opt; | |
6eaaa5d5 FW |
765 | if (!type->wait_pipe) |
766 | type->wait_pipe = default_wait_pipe; | |
767 | ||
adf9f195 | 768 | |
60a11774 | 769 | #ifdef CONFIG_FTRACE_STARTUP_TEST |
b2821ae6 | 770 | if (type->selftest && !tracing_selftest_disabled) { |
60a11774 | 771 | struct tracer *saved_tracer = current_trace; |
60a11774 | 772 | struct trace_array *tr = &global_trace; |
ff32504f | 773 | |
60a11774 SR |
774 | /* |
775 | * Run a selftest on this tracer. | |
776 | * Here we reset the trace buffer, and set the current | |
777 | * tracer to be this tracer. The tracer can then run some | |
778 | * internal tracing to verify that everything is in order. | |
779 | * If we fail, we do not register this tracer. | |
780 | */ | |
76f0d073 | 781 | tracing_reset_online_cpus(tr); |
86fa2f60 | 782 | |
60a11774 | 783 | current_trace = type; |
60a11774 SR |
784 | /* the test is responsible for initializing and enabling */ |
785 | pr_info("Testing tracer %s: ", type->name); | |
786 | ret = type->selftest(type, tr); | |
787 | /* the test is responsible for resetting too */ | |
788 | current_trace = saved_tracer; | |
60a11774 SR |
789 | if (ret) { |
790 | printk(KERN_CONT "FAILED!\n"); | |
791 | goto out; | |
792 | } | |
1d4db00a | 793 | /* Only reset on passing, to avoid touching corrupted buffers */ |
76f0d073 | 794 | tracing_reset_online_cpus(tr); |
86fa2f60 | 795 | |
60a11774 SR |
796 | printk(KERN_CONT "PASSED\n"); |
797 | } | |
798 | #endif | |
799 | ||
bc0c38d1 SR |
800 | type->next = trace_types; |
801 | trace_types = type; | |
60a11774 | 802 | |
bc0c38d1 | 803 | out: |
8e1b82e0 | 804 | tracing_selftest_running = false; |
bc0c38d1 SR |
805 | mutex_unlock(&trace_types_lock); |
806 | ||
dac74940 SR |
807 | if (ret || !default_bootup_tracer) |
808 | goto out_unlock; | |
809 | ||
ee6c2c1b | 810 | if (strncmp(default_bootup_tracer, type->name, MAX_TRACER_SIZE)) |
dac74940 SR |
811 | goto out_unlock; |
812 | ||
813 | printk(KERN_INFO "Starting tracer '%s'\n", type->name); | |
814 | /* Do we want this tracer to start on bootup? */ | |
815 | tracing_set_tracer(type->name); | |
816 | default_bootup_tracer = NULL; | |
817 | /* disable other selftests, since this will break it. */ | |
818 | tracing_selftest_disabled = 1; | |
b2821ae6 | 819 | #ifdef CONFIG_FTRACE_STARTUP_TEST |
dac74940 SR |
820 | printk(KERN_INFO "Disabling FTRACE selftests due to running tracer '%s'\n", |
821 | type->name); | |
b2821ae6 | 822 | #endif |
b2821ae6 | 823 | |
dac74940 | 824 | out_unlock: |
b2821ae6 | 825 | lock_kernel(); |
bc0c38d1 SR |
826 | return ret; |
827 | } | |
828 | ||
829 | void unregister_tracer(struct tracer *type) | |
830 | { | |
831 | struct tracer **t; | |
bc0c38d1 SR |
832 | |
833 | mutex_lock(&trace_types_lock); | |
834 | for (t = &trace_types; *t; t = &(*t)->next) { | |
835 | if (*t == type) | |
836 | goto found; | |
837 | } | |
ee6c2c1b | 838 | pr_info("Tracer %s not registered\n", type->name); |
bc0c38d1 SR |
839 | goto out; |
840 | ||
841 | found: | |
842 | *t = (*t)->next; | |
b5db03c4 ACM |
843 | |
844 | if (type == current_trace && tracer_enabled) { | |
845 | tracer_enabled = 0; | |
846 | tracing_stop(); | |
847 | if (current_trace->stop) | |
848 | current_trace->stop(&global_trace); | |
849 | current_trace = &nop_trace; | |
850 | } | |
ee6c2c1b | 851 | out: |
bc0c38d1 SR |
852 | mutex_unlock(&trace_types_lock); |
853 | } | |
854 | ||
283740c6 | 855 | static void __tracing_reset(struct ring_buffer *buffer, int cpu) |
bc0c38d1 | 856 | { |
d769041f | 857 | ftrace_disable_cpu(); |
283740c6 | 858 | ring_buffer_reset_cpu(buffer, cpu); |
d769041f | 859 | ftrace_enable_cpu(); |
bc0c38d1 SR |
860 | } |
861 | ||
f633903a SR |
862 | void tracing_reset(struct trace_array *tr, int cpu) |
863 | { | |
864 | struct ring_buffer *buffer = tr->buffer; | |
865 | ||
866 | ring_buffer_record_disable(buffer); | |
867 | ||
868 | /* Make sure all commits have finished */ | |
869 | synchronize_sched(); | |
283740c6 | 870 | __tracing_reset(buffer, cpu); |
f633903a SR |
871 | |
872 | ring_buffer_record_enable(buffer); | |
873 | } | |
874 | ||
213cc060 PE |
875 | void tracing_reset_online_cpus(struct trace_array *tr) |
876 | { | |
621968cd | 877 | struct ring_buffer *buffer = tr->buffer; |
213cc060 PE |
878 | int cpu; |
879 | ||
621968cd SR |
880 | ring_buffer_record_disable(buffer); |
881 | ||
882 | /* Make sure all commits have finished */ | |
883 | synchronize_sched(); | |
884 | ||
213cc060 PE |
885 | tr->time_start = ftrace_now(tr->cpu); |
886 | ||
887 | for_each_online_cpu(cpu) | |
283740c6 | 888 | __tracing_reset(buffer, cpu); |
621968cd SR |
889 | |
890 | ring_buffer_record_enable(buffer); | |
213cc060 PE |
891 | } |
892 | ||
9456f0fa SR |
893 | void tracing_reset_current(int cpu) |
894 | { | |
895 | tracing_reset(&global_trace, cpu); | |
896 | } | |
897 | ||
898 | void tracing_reset_current_online_cpus(void) | |
899 | { | |
900 | tracing_reset_online_cpus(&global_trace); | |
901 | } | |
902 | ||
bc0c38d1 | 903 | #define SAVED_CMDLINES 128 |
2c7eea4c | 904 | #define NO_CMDLINE_MAP UINT_MAX |
bc0c38d1 SR |
905 | static unsigned map_pid_to_cmdline[PID_MAX_DEFAULT+1]; |
906 | static unsigned map_cmdline_to_pid[SAVED_CMDLINES]; | |
907 | static char saved_cmdlines[SAVED_CMDLINES][TASK_COMM_LEN]; | |
908 | static int cmdline_idx; | |
edc35bd7 | 909 | static arch_spinlock_t trace_cmdline_lock = __ARCH_SPIN_LOCK_UNLOCKED; |
25b0b44a | 910 | |
25b0b44a | 911 | /* temporary disable recording */ |
4fd27358 | 912 | static atomic_t trace_record_cmdline_disabled __read_mostly; |
bc0c38d1 SR |
913 | |
914 | static void trace_init_cmdlines(void) | |
915 | { | |
2c7eea4c TG |
916 | memset(&map_pid_to_cmdline, NO_CMDLINE_MAP, sizeof(map_pid_to_cmdline)); |
917 | memset(&map_cmdline_to_pid, NO_CMDLINE_MAP, sizeof(map_cmdline_to_pid)); | |
bc0c38d1 SR |
918 | cmdline_idx = 0; |
919 | } | |
920 | ||
b5130b1e CE |
921 | int is_tracing_stopped(void) |
922 | { | |
923 | return trace_stop_count; | |
924 | } | |
925 | ||
69bb54ec SR |
926 | /** |
927 | * ftrace_off_permanent - disable all ftrace code permanently | |
928 | * | |
929 | * This should only be called when a serious anomally has | |
930 | * been detected. This will turn off the function tracing, | |
931 | * ring buffers, and other tracing utilites. It takes no | |
932 | * locks and can be called from any context. | |
933 | */ | |
934 | void ftrace_off_permanent(void) | |
935 | { | |
936 | tracing_disabled = 1; | |
937 | ftrace_stop(); | |
938 | tracing_off_permanent(); | |
939 | } | |
940 | ||
0f048701 SR |
941 | /** |
942 | * tracing_start - quick start of the tracer | |
943 | * | |
944 | * If tracing is enabled but was stopped by tracing_stop, | |
945 | * this will start the tracer back up. | |
946 | */ | |
947 | void tracing_start(void) | |
948 | { | |
949 | struct ring_buffer *buffer; | |
950 | unsigned long flags; | |
951 | ||
952 | if (tracing_disabled) | |
953 | return; | |
954 | ||
955 | spin_lock_irqsave(&tracing_start_lock, flags); | |
b06a8301 SR |
956 | if (--trace_stop_count) { |
957 | if (trace_stop_count < 0) { | |
958 | /* Someone screwed up their debugging */ | |
959 | WARN_ON_ONCE(1); | |
960 | trace_stop_count = 0; | |
961 | } | |
0f048701 SR |
962 | goto out; |
963 | } | |
964 | ||
a2f80714 SR |
965 | /* Prevent the buffers from switching */ |
966 | arch_spin_lock(&ftrace_max_lock); | |
0f048701 SR |
967 | |
968 | buffer = global_trace.buffer; | |
969 | if (buffer) | |
970 | ring_buffer_record_enable(buffer); | |
971 | ||
972 | buffer = max_tr.buffer; | |
973 | if (buffer) | |
974 | ring_buffer_record_enable(buffer); | |
975 | ||
a2f80714 SR |
976 | arch_spin_unlock(&ftrace_max_lock); |
977 | ||
0f048701 SR |
978 | ftrace_start(); |
979 | out: | |
980 | spin_unlock_irqrestore(&tracing_start_lock, flags); | |
981 | } | |
982 | ||
983 | /** | |
984 | * tracing_stop - quick stop of the tracer | |
985 | * | |
986 | * Light weight way to stop tracing. Use in conjunction with | |
987 | * tracing_start. | |
988 | */ | |
989 | void tracing_stop(void) | |
990 | { | |
991 | struct ring_buffer *buffer; | |
992 | unsigned long flags; | |
993 | ||
994 | ftrace_stop(); | |
995 | spin_lock_irqsave(&tracing_start_lock, flags); | |
996 | if (trace_stop_count++) | |
997 | goto out; | |
998 | ||
a2f80714 SR |
999 | /* Prevent the buffers from switching */ |
1000 | arch_spin_lock(&ftrace_max_lock); | |
1001 | ||
0f048701 SR |
1002 | buffer = global_trace.buffer; |
1003 | if (buffer) | |
1004 | ring_buffer_record_disable(buffer); | |
1005 | ||
1006 | buffer = max_tr.buffer; | |
1007 | if (buffer) | |
1008 | ring_buffer_record_disable(buffer); | |
1009 | ||
a2f80714 SR |
1010 | arch_spin_unlock(&ftrace_max_lock); |
1011 | ||
0f048701 SR |
1012 | out: |
1013 | spin_unlock_irqrestore(&tracing_start_lock, flags); | |
1014 | } | |
1015 | ||
e309b41d | 1016 | void trace_stop_cmdline_recording(void); |
bc0c38d1 | 1017 | |
e309b41d | 1018 | static void trace_save_cmdline(struct task_struct *tsk) |
bc0c38d1 | 1019 | { |
a635cf04 | 1020 | unsigned pid, idx; |
bc0c38d1 SR |
1021 | |
1022 | if (!tsk->pid || unlikely(tsk->pid > PID_MAX_DEFAULT)) | |
1023 | return; | |
1024 | ||
1025 | /* | |
1026 | * It's not the end of the world if we don't get | |
1027 | * the lock, but we also don't want to spin | |
1028 | * nor do we want to disable interrupts, | |
1029 | * so if we miss here, then better luck next time. | |
1030 | */ | |
0199c4e6 | 1031 | if (!arch_spin_trylock(&trace_cmdline_lock)) |
bc0c38d1 SR |
1032 | return; |
1033 | ||
1034 | idx = map_pid_to_cmdline[tsk->pid]; | |
2c7eea4c | 1035 | if (idx == NO_CMDLINE_MAP) { |
bc0c38d1 SR |
1036 | idx = (cmdline_idx + 1) % SAVED_CMDLINES; |
1037 | ||
a635cf04 CE |
1038 | /* |
1039 | * Check whether the cmdline buffer at idx has a pid | |
1040 | * mapped. We are going to overwrite that entry so we | |
1041 | * need to clear the map_pid_to_cmdline. Otherwise we | |
1042 | * would read the new comm for the old pid. | |
1043 | */ | |
1044 | pid = map_cmdline_to_pid[idx]; | |
1045 | if (pid != NO_CMDLINE_MAP) | |
1046 | map_pid_to_cmdline[pid] = NO_CMDLINE_MAP; | |
bc0c38d1 | 1047 | |
a635cf04 | 1048 | map_cmdline_to_pid[idx] = tsk->pid; |
bc0c38d1 SR |
1049 | map_pid_to_cmdline[tsk->pid] = idx; |
1050 | ||
1051 | cmdline_idx = idx; | |
1052 | } | |
1053 | ||
1054 | memcpy(&saved_cmdlines[idx], tsk->comm, TASK_COMM_LEN); | |
1055 | ||
0199c4e6 | 1056 | arch_spin_unlock(&trace_cmdline_lock); |
bc0c38d1 SR |
1057 | } |
1058 | ||
4ca53085 | 1059 | void trace_find_cmdline(int pid, char comm[]) |
bc0c38d1 | 1060 | { |
bc0c38d1 SR |
1061 | unsigned map; |
1062 | ||
4ca53085 SR |
1063 | if (!pid) { |
1064 | strcpy(comm, "<idle>"); | |
1065 | return; | |
1066 | } | |
bc0c38d1 | 1067 | |
74bf4076 SR |
1068 | if (WARN_ON_ONCE(pid < 0)) { |
1069 | strcpy(comm, "<XXX>"); | |
1070 | return; | |
1071 | } | |
1072 | ||
4ca53085 SR |
1073 | if (pid > PID_MAX_DEFAULT) { |
1074 | strcpy(comm, "<...>"); | |
1075 | return; | |
1076 | } | |
bc0c38d1 | 1077 | |
5b6045a9 | 1078 | preempt_disable(); |
0199c4e6 | 1079 | arch_spin_lock(&trace_cmdline_lock); |
bc0c38d1 | 1080 | map = map_pid_to_cmdline[pid]; |
50d88758 TG |
1081 | if (map != NO_CMDLINE_MAP) |
1082 | strcpy(comm, saved_cmdlines[map]); | |
1083 | else | |
1084 | strcpy(comm, "<...>"); | |
bc0c38d1 | 1085 | |
0199c4e6 | 1086 | arch_spin_unlock(&trace_cmdline_lock); |
5b6045a9 | 1087 | preempt_enable(); |
bc0c38d1 SR |
1088 | } |
1089 | ||
e309b41d | 1090 | void tracing_record_cmdline(struct task_struct *tsk) |
bc0c38d1 | 1091 | { |
18aecd36 TG |
1092 | if (atomic_read(&trace_record_cmdline_disabled) || !tracer_enabled || |
1093 | !tracing_is_on()) | |
bc0c38d1 SR |
1094 | return; |
1095 | ||
1096 | trace_save_cmdline(tsk); | |
1097 | } | |
1098 | ||
45dcd8b8 | 1099 | void |
38697053 SR |
1100 | tracing_generic_entry_update(struct trace_entry *entry, unsigned long flags, |
1101 | int pc) | |
bc0c38d1 SR |
1102 | { |
1103 | struct task_struct *tsk = current; | |
bc0c38d1 | 1104 | |
777e208d SR |
1105 | entry->preempt_count = pc & 0xff; |
1106 | entry->pid = (tsk) ? tsk->pid : 0; | |
637e7e86 | 1107 | entry->lock_depth = (tsk) ? tsk->lock_depth : 0; |
777e208d | 1108 | entry->flags = |
9244489a | 1109 | #ifdef CONFIG_TRACE_IRQFLAGS_SUPPORT |
2e2ca155 | 1110 | (irqs_disabled_flags(flags) ? TRACE_FLAG_IRQS_OFF : 0) | |
9244489a SR |
1111 | #else |
1112 | TRACE_FLAG_IRQS_NOSUPPORT | | |
1113 | #endif | |
bc0c38d1 SR |
1114 | ((pc & HARDIRQ_MASK) ? TRACE_FLAG_HARDIRQ : 0) | |
1115 | ((pc & SOFTIRQ_MASK) ? TRACE_FLAG_SOFTIRQ : 0) | | |
1116 | (need_resched() ? TRACE_FLAG_NEED_RESCHED : 0); | |
1117 | } | |
f413cdb8 | 1118 | EXPORT_SYMBOL_GPL(tracing_generic_entry_update); |
bc0c38d1 | 1119 | |
e77405ad SR |
1120 | struct ring_buffer_event * |
1121 | trace_buffer_lock_reserve(struct ring_buffer *buffer, | |
1122 | int type, | |
1123 | unsigned long len, | |
1124 | unsigned long flags, int pc) | |
51a763dd ACM |
1125 | { |
1126 | struct ring_buffer_event *event; | |
1127 | ||
e77405ad | 1128 | event = ring_buffer_lock_reserve(buffer, len); |
51a763dd ACM |
1129 | if (event != NULL) { |
1130 | struct trace_entry *ent = ring_buffer_event_data(event); | |
1131 | ||
1132 | tracing_generic_entry_update(ent, flags, pc); | |
1133 | ent->type = type; | |
1134 | } | |
1135 | ||
1136 | return event; | |
1137 | } | |
51a763dd | 1138 | |
e77405ad SR |
1139 | static inline void |
1140 | __trace_buffer_unlock_commit(struct ring_buffer *buffer, | |
1141 | struct ring_buffer_event *event, | |
1142 | unsigned long flags, int pc, | |
1143 | int wake) | |
51a763dd | 1144 | { |
e77405ad | 1145 | ring_buffer_unlock_commit(buffer, event); |
51a763dd | 1146 | |
e77405ad SR |
1147 | ftrace_trace_stack(buffer, flags, 6, pc); |
1148 | ftrace_trace_userstack(buffer, flags, pc); | |
07edf712 FW |
1149 | |
1150 | if (wake) | |
1151 | trace_wake_up(); | |
1152 | } | |
1153 | ||
e77405ad SR |
1154 | void trace_buffer_unlock_commit(struct ring_buffer *buffer, |
1155 | struct ring_buffer_event *event, | |
1156 | unsigned long flags, int pc) | |
07edf712 | 1157 | { |
e77405ad | 1158 | __trace_buffer_unlock_commit(buffer, event, flags, pc, 1); |
51a763dd ACM |
1159 | } |
1160 | ||
ef5580d0 | 1161 | struct ring_buffer_event * |
e77405ad SR |
1162 | trace_current_buffer_lock_reserve(struct ring_buffer **current_rb, |
1163 | int type, unsigned long len, | |
ef5580d0 SR |
1164 | unsigned long flags, int pc) |
1165 | { | |
e77405ad SR |
1166 | *current_rb = global_trace.buffer; |
1167 | return trace_buffer_lock_reserve(*current_rb, | |
ef5580d0 SR |
1168 | type, len, flags, pc); |
1169 | } | |
94487d6d | 1170 | EXPORT_SYMBOL_GPL(trace_current_buffer_lock_reserve); |
ef5580d0 | 1171 | |
e77405ad SR |
1172 | void trace_current_buffer_unlock_commit(struct ring_buffer *buffer, |
1173 | struct ring_buffer_event *event, | |
ef5580d0 SR |
1174 | unsigned long flags, int pc) |
1175 | { | |
e77405ad | 1176 | __trace_buffer_unlock_commit(buffer, event, flags, pc, 1); |
07edf712 | 1177 | } |
94487d6d | 1178 | EXPORT_SYMBOL_GPL(trace_current_buffer_unlock_commit); |
07edf712 | 1179 | |
e77405ad SR |
1180 | void trace_nowake_buffer_unlock_commit(struct ring_buffer *buffer, |
1181 | struct ring_buffer_event *event, | |
1182 | unsigned long flags, int pc) | |
07edf712 | 1183 | { |
e77405ad | 1184 | __trace_buffer_unlock_commit(buffer, event, flags, pc, 0); |
77d9f465 | 1185 | } |
94487d6d | 1186 | EXPORT_SYMBOL_GPL(trace_nowake_buffer_unlock_commit); |
77d9f465 | 1187 | |
e77405ad SR |
1188 | void trace_current_buffer_discard_commit(struct ring_buffer *buffer, |
1189 | struct ring_buffer_event *event) | |
77d9f465 | 1190 | { |
e77405ad | 1191 | ring_buffer_discard_commit(buffer, event); |
ef5580d0 | 1192 | } |
12acd473 | 1193 | EXPORT_SYMBOL_GPL(trace_current_buffer_discard_commit); |
ef5580d0 | 1194 | |
e309b41d | 1195 | void |
7be42151 | 1196 | trace_function(struct trace_array *tr, |
38697053 SR |
1197 | unsigned long ip, unsigned long parent_ip, unsigned long flags, |
1198 | int pc) | |
bc0c38d1 | 1199 | { |
e1112b4d | 1200 | struct ftrace_event_call *call = &event_function; |
e77405ad | 1201 | struct ring_buffer *buffer = tr->buffer; |
3928a8a2 | 1202 | struct ring_buffer_event *event; |
777e208d | 1203 | struct ftrace_entry *entry; |
bc0c38d1 | 1204 | |
d769041f | 1205 | /* If we are reading the ring buffer, don't trace */ |
dd17c8f7 | 1206 | if (unlikely(__this_cpu_read(ftrace_cpu_disabled))) |
d769041f SR |
1207 | return; |
1208 | ||
e77405ad | 1209 | event = trace_buffer_lock_reserve(buffer, TRACE_FN, sizeof(*entry), |
51a763dd | 1210 | flags, pc); |
3928a8a2 SR |
1211 | if (!event) |
1212 | return; | |
1213 | entry = ring_buffer_event_data(event); | |
777e208d SR |
1214 | entry->ip = ip; |
1215 | entry->parent_ip = parent_ip; | |
e1112b4d | 1216 | |
e77405ad SR |
1217 | if (!filter_check_discard(call, entry, buffer, event)) |
1218 | ring_buffer_unlock_commit(buffer, event); | |
bc0c38d1 SR |
1219 | } |
1220 | ||
e309b41d | 1221 | void |
2e0f5761 | 1222 | ftrace(struct trace_array *tr, struct trace_array_cpu *data, |
38697053 SR |
1223 | unsigned long ip, unsigned long parent_ip, unsigned long flags, |
1224 | int pc) | |
2e0f5761 IM |
1225 | { |
1226 | if (likely(!atomic_read(&data->disabled))) | |
7be42151 | 1227 | trace_function(tr, ip, parent_ip, flags, pc); |
2e0f5761 IM |
1228 | } |
1229 | ||
c0a0d0d3 | 1230 | #ifdef CONFIG_STACKTRACE |
e77405ad | 1231 | static void __ftrace_trace_stack(struct ring_buffer *buffer, |
53614991 SR |
1232 | unsigned long flags, |
1233 | int skip, int pc) | |
86387f7e | 1234 | { |
e1112b4d | 1235 | struct ftrace_event_call *call = &event_kernel_stack; |
3928a8a2 | 1236 | struct ring_buffer_event *event; |
777e208d | 1237 | struct stack_entry *entry; |
86387f7e IM |
1238 | struct stack_trace trace; |
1239 | ||
e77405ad | 1240 | event = trace_buffer_lock_reserve(buffer, TRACE_STACK, |
51a763dd | 1241 | sizeof(*entry), flags, pc); |
3928a8a2 SR |
1242 | if (!event) |
1243 | return; | |
1244 | entry = ring_buffer_event_data(event); | |
777e208d | 1245 | memset(&entry->caller, 0, sizeof(entry->caller)); |
86387f7e IM |
1246 | |
1247 | trace.nr_entries = 0; | |
1248 | trace.max_entries = FTRACE_STACK_ENTRIES; | |
1249 | trace.skip = skip; | |
777e208d | 1250 | trace.entries = entry->caller; |
86387f7e IM |
1251 | |
1252 | save_stack_trace(&trace); | |
e77405ad SR |
1253 | if (!filter_check_discard(call, entry, buffer, event)) |
1254 | ring_buffer_unlock_commit(buffer, event); | |
f0a920d5 IM |
1255 | } |
1256 | ||
e77405ad SR |
1257 | void ftrace_trace_stack(struct ring_buffer *buffer, unsigned long flags, |
1258 | int skip, int pc) | |
53614991 SR |
1259 | { |
1260 | if (!(trace_flags & TRACE_ITER_STACKTRACE)) | |
1261 | return; | |
1262 | ||
e77405ad | 1263 | __ftrace_trace_stack(buffer, flags, skip, pc); |
53614991 SR |
1264 | } |
1265 | ||
c0a0d0d3 FW |
1266 | void __trace_stack(struct trace_array *tr, unsigned long flags, int skip, |
1267 | int pc) | |
38697053 | 1268 | { |
e77405ad | 1269 | __ftrace_trace_stack(tr->buffer, flags, skip, pc); |
38697053 SR |
1270 | } |
1271 | ||
03889384 SR |
1272 | /** |
1273 | * trace_dump_stack - record a stack back trace in the trace buffer | |
1274 | */ | |
1275 | void trace_dump_stack(void) | |
1276 | { | |
1277 | unsigned long flags; | |
1278 | ||
1279 | if (tracing_disabled || tracing_selftest_running) | |
e36c5458 | 1280 | return; |
03889384 SR |
1281 | |
1282 | local_save_flags(flags); | |
1283 | ||
1284 | /* skipping 3 traces, seems to get us at the caller of this function */ | |
1285 | __ftrace_trace_stack(global_trace.buffer, flags, 3, preempt_count()); | |
1286 | } | |
1287 | ||
e77405ad SR |
1288 | void |
1289 | ftrace_trace_userstack(struct ring_buffer *buffer, unsigned long flags, int pc) | |
02b67518 | 1290 | { |
e1112b4d | 1291 | struct ftrace_event_call *call = &event_user_stack; |
8d7c6a96 | 1292 | struct ring_buffer_event *event; |
02b67518 TE |
1293 | struct userstack_entry *entry; |
1294 | struct stack_trace trace; | |
02b67518 TE |
1295 | |
1296 | if (!(trace_flags & TRACE_ITER_USERSTACKTRACE)) | |
1297 | return; | |
1298 | ||
b6345879 SR |
1299 | /* |
1300 | * NMIs can not handle page faults, even with fix ups. | |
1301 | * The save user stack can (and often does) fault. | |
1302 | */ | |
1303 | if (unlikely(in_nmi())) | |
1304 | return; | |
02b67518 | 1305 | |
e77405ad | 1306 | event = trace_buffer_lock_reserve(buffer, TRACE_USER_STACK, |
51a763dd | 1307 | sizeof(*entry), flags, pc); |
02b67518 TE |
1308 | if (!event) |
1309 | return; | |
1310 | entry = ring_buffer_event_data(event); | |
02b67518 | 1311 | |
48659d31 | 1312 | entry->tgid = current->tgid; |
02b67518 TE |
1313 | memset(&entry->caller, 0, sizeof(entry->caller)); |
1314 | ||
1315 | trace.nr_entries = 0; | |
1316 | trace.max_entries = FTRACE_STACK_ENTRIES; | |
1317 | trace.skip = 0; | |
1318 | trace.entries = entry->caller; | |
1319 | ||
1320 | save_stack_trace_user(&trace); | |
e77405ad SR |
1321 | if (!filter_check_discard(call, entry, buffer, event)) |
1322 | ring_buffer_unlock_commit(buffer, event); | |
02b67518 TE |
1323 | } |
1324 | ||
4fd27358 HE |
1325 | #ifdef UNUSED |
1326 | static void __trace_userstack(struct trace_array *tr, unsigned long flags) | |
02b67518 | 1327 | { |
7be42151 | 1328 | ftrace_trace_userstack(tr, flags, preempt_count()); |
02b67518 | 1329 | } |
4fd27358 | 1330 | #endif /* UNUSED */ |
02b67518 | 1331 | |
c0a0d0d3 FW |
1332 | #endif /* CONFIG_STACKTRACE */ |
1333 | ||
38697053 | 1334 | static void |
7be42151 | 1335 | ftrace_trace_special(void *__tr, |
38697053 SR |
1336 | unsigned long arg1, unsigned long arg2, unsigned long arg3, |
1337 | int pc) | |
a4feb834 | 1338 | { |
60ba7702 | 1339 | struct ftrace_event_call *call = &event_special; |
3928a8a2 | 1340 | struct ring_buffer_event *event; |
a4feb834 | 1341 | struct trace_array *tr = __tr; |
e77405ad | 1342 | struct ring_buffer *buffer = tr->buffer; |
777e208d | 1343 | struct special_entry *entry; |
a4feb834 | 1344 | |
e77405ad | 1345 | event = trace_buffer_lock_reserve(buffer, TRACE_SPECIAL, |
51a763dd | 1346 | sizeof(*entry), 0, pc); |
3928a8a2 SR |
1347 | if (!event) |
1348 | return; | |
1349 | entry = ring_buffer_event_data(event); | |
777e208d SR |
1350 | entry->arg1 = arg1; |
1351 | entry->arg2 = arg2; | |
1352 | entry->arg3 = arg3; | |
60ba7702 SR |
1353 | |
1354 | if (!filter_check_discard(call, entry, buffer, event)) | |
1355 | trace_buffer_unlock_commit(buffer, event, 0, pc); | |
a4feb834 IM |
1356 | } |
1357 | ||
38697053 SR |
1358 | void |
1359 | __trace_special(void *__tr, void *__data, | |
1360 | unsigned long arg1, unsigned long arg2, unsigned long arg3) | |
1361 | { | |
7be42151 | 1362 | ftrace_trace_special(__tr, arg1, arg2, arg3, preempt_count()); |
38697053 SR |
1363 | } |
1364 | ||
4902f884 SR |
1365 | void |
1366 | ftrace_special(unsigned long arg1, unsigned long arg2, unsigned long arg3) | |
1367 | { | |
1368 | struct trace_array *tr = &global_trace; | |
1369 | struct trace_array_cpu *data; | |
5aa1ba6a | 1370 | unsigned long flags; |
4902f884 | 1371 | int cpu; |
38697053 | 1372 | int pc; |
4902f884 | 1373 | |
c76f0694 | 1374 | if (tracing_disabled) |
4902f884 SR |
1375 | return; |
1376 | ||
38697053 | 1377 | pc = preempt_count(); |
5aa1ba6a | 1378 | local_irq_save(flags); |
4902f884 SR |
1379 | cpu = raw_smp_processor_id(); |
1380 | data = tr->data[cpu]; | |
4902f884 | 1381 | |
5aa1ba6a | 1382 | if (likely(atomic_inc_return(&data->disabled) == 1)) |
7be42151 | 1383 | ftrace_trace_special(tr, arg1, arg2, arg3, pc); |
4902f884 | 1384 | |
5aa1ba6a SR |
1385 | atomic_dec(&data->disabled); |
1386 | local_irq_restore(flags); | |
4902f884 SR |
1387 | } |
1388 | ||
769b0441 | 1389 | /** |
48ead020 | 1390 | * trace_vbprintk - write binary msg to tracing buffer |
769b0441 FW |
1391 | * |
1392 | */ | |
40ce74f1 | 1393 | int trace_vbprintk(unsigned long ip, const char *fmt, va_list args) |
769b0441 | 1394 | { |
445c8951 | 1395 | static arch_spinlock_t trace_buf_lock = |
edc35bd7 | 1396 | (arch_spinlock_t)__ARCH_SPIN_LOCK_UNLOCKED; |
769b0441 FW |
1397 | static u32 trace_buf[TRACE_BUF_SIZE]; |
1398 | ||
e1112b4d | 1399 | struct ftrace_event_call *call = &event_bprint; |
769b0441 | 1400 | struct ring_buffer_event *event; |
e77405ad | 1401 | struct ring_buffer *buffer; |
769b0441 FW |
1402 | struct trace_array *tr = &global_trace; |
1403 | struct trace_array_cpu *data; | |
48ead020 | 1404 | struct bprint_entry *entry; |
769b0441 | 1405 | unsigned long flags; |
3189cdb3 | 1406 | int disable; |
769b0441 FW |
1407 | int resched; |
1408 | int cpu, len = 0, size, pc; | |
1409 | ||
1410 | if (unlikely(tracing_selftest_running || tracing_disabled)) | |
1411 | return 0; | |
1412 | ||
1413 | /* Don't pollute graph traces with trace_vprintk internals */ | |
1414 | pause_graph_tracing(); | |
1415 | ||
1416 | pc = preempt_count(); | |
1417 | resched = ftrace_preempt_disable(); | |
1418 | cpu = raw_smp_processor_id(); | |
1419 | data = tr->data[cpu]; | |
1420 | ||
3189cdb3 SR |
1421 | disable = atomic_inc_return(&data->disabled); |
1422 | if (unlikely(disable != 1)) | |
769b0441 FW |
1423 | goto out; |
1424 | ||
80370cb7 SR |
1425 | /* Lockdep uses trace_printk for lock tracing */ |
1426 | local_irq_save(flags); | |
0199c4e6 | 1427 | arch_spin_lock(&trace_buf_lock); |
769b0441 FW |
1428 | len = vbin_printf(trace_buf, TRACE_BUF_SIZE, fmt, args); |
1429 | ||
1430 | if (len > TRACE_BUF_SIZE || len < 0) | |
1431 | goto out_unlock; | |
1432 | ||
1433 | size = sizeof(*entry) + sizeof(u32) * len; | |
e77405ad SR |
1434 | buffer = tr->buffer; |
1435 | event = trace_buffer_lock_reserve(buffer, TRACE_BPRINT, size, | |
1436 | flags, pc); | |
769b0441 FW |
1437 | if (!event) |
1438 | goto out_unlock; | |
1439 | entry = ring_buffer_event_data(event); | |
1440 | entry->ip = ip; | |
769b0441 FW |
1441 | entry->fmt = fmt; |
1442 | ||
1443 | memcpy(entry->buf, trace_buf, sizeof(u32) * len); | |
d931369b | 1444 | if (!filter_check_discard(call, entry, buffer, event)) { |
e77405ad | 1445 | ring_buffer_unlock_commit(buffer, event); |
d931369b SR |
1446 | ftrace_trace_stack(buffer, flags, 6, pc); |
1447 | } | |
769b0441 FW |
1448 | |
1449 | out_unlock: | |
0199c4e6 | 1450 | arch_spin_unlock(&trace_buf_lock); |
80370cb7 | 1451 | local_irq_restore(flags); |
769b0441 FW |
1452 | |
1453 | out: | |
3189cdb3 | 1454 | atomic_dec_return(&data->disabled); |
769b0441 FW |
1455 | ftrace_preempt_enable(resched); |
1456 | unpause_graph_tracing(); | |
1457 | ||
1458 | return len; | |
1459 | } | |
48ead020 FW |
1460 | EXPORT_SYMBOL_GPL(trace_vbprintk); |
1461 | ||
659372d3 SR |
1462 | int trace_array_printk(struct trace_array *tr, |
1463 | unsigned long ip, const char *fmt, ...) | |
1464 | { | |
1465 | int ret; | |
1466 | va_list ap; | |
1467 | ||
1468 | if (!(trace_flags & TRACE_ITER_PRINTK)) | |
1469 | return 0; | |
1470 | ||
1471 | va_start(ap, fmt); | |
1472 | ret = trace_array_vprintk(tr, ip, fmt, ap); | |
1473 | va_end(ap); | |
1474 | return ret; | |
1475 | } | |
1476 | ||
1477 | int trace_array_vprintk(struct trace_array *tr, | |
1478 | unsigned long ip, const char *fmt, va_list args) | |
48ead020 | 1479 | { |
edc35bd7 | 1480 | static arch_spinlock_t trace_buf_lock = __ARCH_SPIN_LOCK_UNLOCKED; |
48ead020 FW |
1481 | static char trace_buf[TRACE_BUF_SIZE]; |
1482 | ||
e1112b4d | 1483 | struct ftrace_event_call *call = &event_print; |
48ead020 | 1484 | struct ring_buffer_event *event; |
e77405ad | 1485 | struct ring_buffer *buffer; |
48ead020 FW |
1486 | struct trace_array_cpu *data; |
1487 | int cpu, len = 0, size, pc; | |
1488 | struct print_entry *entry; | |
1489 | unsigned long irq_flags; | |
3189cdb3 | 1490 | int disable; |
48ead020 FW |
1491 | |
1492 | if (tracing_disabled || tracing_selftest_running) | |
1493 | return 0; | |
1494 | ||
1495 | pc = preempt_count(); | |
1496 | preempt_disable_notrace(); | |
1497 | cpu = raw_smp_processor_id(); | |
1498 | data = tr->data[cpu]; | |
1499 | ||
3189cdb3 SR |
1500 | disable = atomic_inc_return(&data->disabled); |
1501 | if (unlikely(disable != 1)) | |
48ead020 FW |
1502 | goto out; |
1503 | ||
1504 | pause_graph_tracing(); | |
1505 | raw_local_irq_save(irq_flags); | |
0199c4e6 | 1506 | arch_spin_lock(&trace_buf_lock); |
f2942487 | 1507 | len = vsnprintf(trace_buf, TRACE_BUF_SIZE, fmt, args); |
48ead020 FW |
1508 | |
1509 | size = sizeof(*entry) + len + 1; | |
e77405ad SR |
1510 | buffer = tr->buffer; |
1511 | event = trace_buffer_lock_reserve(buffer, TRACE_PRINT, size, | |
1512 | irq_flags, pc); | |
48ead020 FW |
1513 | if (!event) |
1514 | goto out_unlock; | |
1515 | entry = ring_buffer_event_data(event); | |
c13d2f7c | 1516 | entry->ip = ip; |
48ead020 FW |
1517 | |
1518 | memcpy(&entry->buf, trace_buf, len); | |
c13d2f7c | 1519 | entry->buf[len] = '\0'; |
d931369b | 1520 | if (!filter_check_discard(call, entry, buffer, event)) { |
e77405ad | 1521 | ring_buffer_unlock_commit(buffer, event); |
d931369b SR |
1522 | ftrace_trace_stack(buffer, irq_flags, 6, pc); |
1523 | } | |
48ead020 FW |
1524 | |
1525 | out_unlock: | |
0199c4e6 | 1526 | arch_spin_unlock(&trace_buf_lock); |
48ead020 FW |
1527 | raw_local_irq_restore(irq_flags); |
1528 | unpause_graph_tracing(); | |
1529 | out: | |
3189cdb3 | 1530 | atomic_dec_return(&data->disabled); |
48ead020 FW |
1531 | preempt_enable_notrace(); |
1532 | ||
1533 | return len; | |
1534 | } | |
659372d3 SR |
1535 | |
1536 | int trace_vprintk(unsigned long ip, const char *fmt, va_list args) | |
1537 | { | |
a813a159 | 1538 | return trace_array_vprintk(&global_trace, ip, fmt, args); |
659372d3 | 1539 | } |
769b0441 FW |
1540 | EXPORT_SYMBOL_GPL(trace_vprintk); |
1541 | ||
bc0c38d1 SR |
1542 | enum trace_file_type { |
1543 | TRACE_FILE_LAT_FMT = 1, | |
12ef7d44 | 1544 | TRACE_FILE_ANNOTATE = 2, |
bc0c38d1 SR |
1545 | }; |
1546 | ||
e2ac8ef5 | 1547 | static void trace_iterator_increment(struct trace_iterator *iter) |
5a90f577 | 1548 | { |
d769041f SR |
1549 | /* Don't allow ftrace to trace into the ring buffers */ |
1550 | ftrace_disable_cpu(); | |
1551 | ||
5a90f577 | 1552 | iter->idx++; |
d769041f SR |
1553 | if (iter->buffer_iter[iter->cpu]) |
1554 | ring_buffer_read(iter->buffer_iter[iter->cpu], NULL); | |
1555 | ||
1556 | ftrace_enable_cpu(); | |
5a90f577 SR |
1557 | } |
1558 | ||
e309b41d | 1559 | static struct trace_entry * |
bc21b478 SR |
1560 | peek_next_entry(struct trace_iterator *iter, int cpu, u64 *ts, |
1561 | unsigned long *lost_events) | |
dd0e545f | 1562 | { |
3928a8a2 SR |
1563 | struct ring_buffer_event *event; |
1564 | struct ring_buffer_iter *buf_iter = iter->buffer_iter[cpu]; | |
dd0e545f | 1565 | |
d769041f SR |
1566 | /* Don't allow ftrace to trace into the ring buffers */ |
1567 | ftrace_disable_cpu(); | |
1568 | ||
1569 | if (buf_iter) | |
1570 | event = ring_buffer_iter_peek(buf_iter, ts); | |
1571 | else | |
bc21b478 SR |
1572 | event = ring_buffer_peek(iter->tr->buffer, cpu, ts, |
1573 | lost_events); | |
d769041f SR |
1574 | |
1575 | ftrace_enable_cpu(); | |
1576 | ||
3928a8a2 | 1577 | return event ? ring_buffer_event_data(event) : NULL; |
dd0e545f | 1578 | } |
d769041f | 1579 | |
dd0e545f | 1580 | static struct trace_entry * |
bc21b478 SR |
1581 | __find_next_entry(struct trace_iterator *iter, int *ent_cpu, |
1582 | unsigned long *missing_events, u64 *ent_ts) | |
bc0c38d1 | 1583 | { |
3928a8a2 | 1584 | struct ring_buffer *buffer = iter->tr->buffer; |
bc0c38d1 | 1585 | struct trace_entry *ent, *next = NULL; |
aa27497c | 1586 | unsigned long lost_events = 0, next_lost = 0; |
b04cc6b1 | 1587 | int cpu_file = iter->cpu_file; |
3928a8a2 | 1588 | u64 next_ts = 0, ts; |
bc0c38d1 SR |
1589 | int next_cpu = -1; |
1590 | int cpu; | |
1591 | ||
b04cc6b1 FW |
1592 | /* |
1593 | * If we are in a per_cpu trace file, don't bother by iterating over | |
1594 | * all cpu and peek directly. | |
1595 | */ | |
1596 | if (cpu_file > TRACE_PIPE_ALL_CPU) { | |
1597 | if (ring_buffer_empty_cpu(buffer, cpu_file)) | |
1598 | return NULL; | |
bc21b478 | 1599 | ent = peek_next_entry(iter, cpu_file, ent_ts, missing_events); |
b04cc6b1 FW |
1600 | if (ent_cpu) |
1601 | *ent_cpu = cpu_file; | |
1602 | ||
1603 | return ent; | |
1604 | } | |
1605 | ||
ab46428c | 1606 | for_each_tracing_cpu(cpu) { |
dd0e545f | 1607 | |
3928a8a2 SR |
1608 | if (ring_buffer_empty_cpu(buffer, cpu)) |
1609 | continue; | |
dd0e545f | 1610 | |
bc21b478 | 1611 | ent = peek_next_entry(iter, cpu, &ts, &lost_events); |
dd0e545f | 1612 | |
cdd31cd2 IM |
1613 | /* |
1614 | * Pick the entry with the smallest timestamp: | |
1615 | */ | |
3928a8a2 | 1616 | if (ent && (!next || ts < next_ts)) { |
bc0c38d1 SR |
1617 | next = ent; |
1618 | next_cpu = cpu; | |
3928a8a2 | 1619 | next_ts = ts; |
bc21b478 | 1620 | next_lost = lost_events; |
bc0c38d1 SR |
1621 | } |
1622 | } | |
1623 | ||
1624 | if (ent_cpu) | |
1625 | *ent_cpu = next_cpu; | |
1626 | ||
3928a8a2 SR |
1627 | if (ent_ts) |
1628 | *ent_ts = next_ts; | |
1629 | ||
bc21b478 SR |
1630 | if (missing_events) |
1631 | *missing_events = next_lost; | |
1632 | ||
bc0c38d1 SR |
1633 | return next; |
1634 | } | |
1635 | ||
dd0e545f | 1636 | /* Find the next real entry, without updating the iterator itself */ |
c4a8e8be FW |
1637 | struct trace_entry *trace_find_next_entry(struct trace_iterator *iter, |
1638 | int *ent_cpu, u64 *ent_ts) | |
bc0c38d1 | 1639 | { |
bc21b478 | 1640 | return __find_next_entry(iter, ent_cpu, NULL, ent_ts); |
dd0e545f SR |
1641 | } |
1642 | ||
1643 | /* Find the next real entry, and increment the iterator to the next entry */ | |
1644 | static void *find_next_entry_inc(struct trace_iterator *iter) | |
1645 | { | |
bc21b478 SR |
1646 | iter->ent = __find_next_entry(iter, &iter->cpu, |
1647 | &iter->lost_events, &iter->ts); | |
dd0e545f | 1648 | |
3928a8a2 | 1649 | if (iter->ent) |
e2ac8ef5 | 1650 | trace_iterator_increment(iter); |
dd0e545f | 1651 | |
3928a8a2 | 1652 | return iter->ent ? iter : NULL; |
b3806b43 | 1653 | } |
bc0c38d1 | 1654 | |
e309b41d | 1655 | static void trace_consume(struct trace_iterator *iter) |
b3806b43 | 1656 | { |
d769041f SR |
1657 | /* Don't allow ftrace to trace into the ring buffers */ |
1658 | ftrace_disable_cpu(); | |
bc21b478 SR |
1659 | ring_buffer_consume(iter->tr->buffer, iter->cpu, &iter->ts, |
1660 | &iter->lost_events); | |
d769041f | 1661 | ftrace_enable_cpu(); |
bc0c38d1 SR |
1662 | } |
1663 | ||
e309b41d | 1664 | static void *s_next(struct seq_file *m, void *v, loff_t *pos) |
bc0c38d1 SR |
1665 | { |
1666 | struct trace_iterator *iter = m->private; | |
bc0c38d1 | 1667 | int i = (int)*pos; |
4e3c3333 | 1668 | void *ent; |
bc0c38d1 | 1669 | |
a63ce5b3 SR |
1670 | WARN_ON_ONCE(iter->leftover); |
1671 | ||
bc0c38d1 SR |
1672 | (*pos)++; |
1673 | ||
1674 | /* can't go backwards */ | |
1675 | if (iter->idx > i) | |
1676 | return NULL; | |
1677 | ||
1678 | if (iter->idx < 0) | |
1679 | ent = find_next_entry_inc(iter); | |
1680 | else | |
1681 | ent = iter; | |
1682 | ||
1683 | while (ent && iter->idx < i) | |
1684 | ent = find_next_entry_inc(iter); | |
1685 | ||
1686 | iter->pos = *pos; | |
1687 | ||
bc0c38d1 SR |
1688 | return ent; |
1689 | } | |
1690 | ||
2f26ebd5 SR |
1691 | static void tracing_iter_reset(struct trace_iterator *iter, int cpu) |
1692 | { | |
1693 | struct trace_array *tr = iter->tr; | |
1694 | struct ring_buffer_event *event; | |
1695 | struct ring_buffer_iter *buf_iter; | |
1696 | unsigned long entries = 0; | |
1697 | u64 ts; | |
1698 | ||
1699 | tr->data[cpu]->skipped_entries = 0; | |
1700 | ||
1701 | if (!iter->buffer_iter[cpu]) | |
1702 | return; | |
1703 | ||
1704 | buf_iter = iter->buffer_iter[cpu]; | |
1705 | ring_buffer_iter_reset(buf_iter); | |
1706 | ||
1707 | /* | |
1708 | * We could have the case with the max latency tracers | |
1709 | * that a reset never took place on a cpu. This is evident | |
1710 | * by the timestamp being before the start of the buffer. | |
1711 | */ | |
1712 | while ((event = ring_buffer_iter_peek(buf_iter, &ts))) { | |
1713 | if (ts >= iter->tr->time_start) | |
1714 | break; | |
1715 | entries++; | |
1716 | ring_buffer_read(buf_iter, NULL); | |
1717 | } | |
1718 | ||
1719 | tr->data[cpu]->skipped_entries = entries; | |
1720 | } | |
1721 | ||
d7350c3f | 1722 | /* |
d7350c3f FW |
1723 | * The current tracer is copied to avoid a global locking |
1724 | * all around. | |
1725 | */ | |
bc0c38d1 SR |
1726 | static void *s_start(struct seq_file *m, loff_t *pos) |
1727 | { | |
1728 | struct trace_iterator *iter = m->private; | |
d7350c3f | 1729 | static struct tracer *old_tracer; |
b04cc6b1 | 1730 | int cpu_file = iter->cpu_file; |
bc0c38d1 SR |
1731 | void *p = NULL; |
1732 | loff_t l = 0; | |
3928a8a2 | 1733 | int cpu; |
bc0c38d1 | 1734 | |
d7350c3f | 1735 | /* copy the tracer to avoid using a global lock all around */ |
bc0c38d1 | 1736 | mutex_lock(&trace_types_lock); |
d7350c3f FW |
1737 | if (unlikely(old_tracer != current_trace && current_trace)) { |
1738 | old_tracer = current_trace; | |
1739 | *iter->trace = *current_trace; | |
d15f57f2 | 1740 | } |
d7350c3f | 1741 | mutex_unlock(&trace_types_lock); |
bc0c38d1 SR |
1742 | |
1743 | atomic_inc(&trace_record_cmdline_disabled); | |
1744 | ||
bc0c38d1 SR |
1745 | if (*pos != iter->pos) { |
1746 | iter->ent = NULL; | |
1747 | iter->cpu = 0; | |
1748 | iter->idx = -1; | |
1749 | ||
d769041f SR |
1750 | ftrace_disable_cpu(); |
1751 | ||
b04cc6b1 FW |
1752 | if (cpu_file == TRACE_PIPE_ALL_CPU) { |
1753 | for_each_tracing_cpu(cpu) | |
2f26ebd5 | 1754 | tracing_iter_reset(iter, cpu); |
b04cc6b1 | 1755 | } else |
2f26ebd5 | 1756 | tracing_iter_reset(iter, cpu_file); |
bc0c38d1 | 1757 | |
d769041f SR |
1758 | ftrace_enable_cpu(); |
1759 | ||
ac91d854 | 1760 | iter->leftover = 0; |
bc0c38d1 SR |
1761 | for (p = iter; p && l < *pos; p = s_next(m, p, &l)) |
1762 | ; | |
1763 | ||
1764 | } else { | |
a63ce5b3 SR |
1765 | /* |
1766 | * If we overflowed the seq_file before, then we want | |
1767 | * to just reuse the trace_seq buffer again. | |
1768 | */ | |
1769 | if (iter->leftover) | |
1770 | p = iter; | |
1771 | else { | |
1772 | l = *pos - 1; | |
1773 | p = s_next(m, p, &l); | |
1774 | } | |
bc0c38d1 SR |
1775 | } |
1776 | ||
4f535968 | 1777 | trace_event_read_lock(); |
7e53bd42 | 1778 | trace_access_lock(cpu_file); |
bc0c38d1 SR |
1779 | return p; |
1780 | } | |
1781 | ||
1782 | static void s_stop(struct seq_file *m, void *p) | |
1783 | { | |
7e53bd42 LJ |
1784 | struct trace_iterator *iter = m->private; |
1785 | ||
bc0c38d1 | 1786 | atomic_dec(&trace_record_cmdline_disabled); |
7e53bd42 | 1787 | trace_access_unlock(iter->cpu_file); |
4f535968 | 1788 | trace_event_read_unlock(); |
bc0c38d1 SR |
1789 | } |
1790 | ||
e309b41d | 1791 | static void print_lat_help_header(struct seq_file *m) |
bc0c38d1 | 1792 | { |
a6168353 ME |
1793 | seq_puts(m, "# _------=> CPU# \n"); |
1794 | seq_puts(m, "# / _-----=> irqs-off \n"); | |
1795 | seq_puts(m, "# | / _----=> need-resched \n"); | |
1796 | seq_puts(m, "# || / _---=> hardirq/softirq \n"); | |
1797 | seq_puts(m, "# ||| / _--=> preempt-depth \n"); | |
637e7e86 SR |
1798 | seq_puts(m, "# |||| /_--=> lock-depth \n"); |
1799 | seq_puts(m, "# |||||/ delay \n"); | |
1800 | seq_puts(m, "# cmd pid |||||| time | caller \n"); | |
1801 | seq_puts(m, "# \\ / |||||| \\ | / \n"); | |
bc0c38d1 SR |
1802 | } |
1803 | ||
e309b41d | 1804 | static void print_func_help_header(struct seq_file *m) |
bc0c38d1 | 1805 | { |
a6168353 ME |
1806 | seq_puts(m, "# TASK-PID CPU# TIMESTAMP FUNCTION\n"); |
1807 | seq_puts(m, "# | | | | |\n"); | |
bc0c38d1 SR |
1808 | } |
1809 | ||
1810 | ||
62b915f1 | 1811 | void |
bc0c38d1 SR |
1812 | print_trace_header(struct seq_file *m, struct trace_iterator *iter) |
1813 | { | |
1814 | unsigned long sym_flags = (trace_flags & TRACE_ITER_SYM_MASK); | |
1815 | struct trace_array *tr = iter->tr; | |
1816 | struct trace_array_cpu *data = tr->data[tr->cpu]; | |
1817 | struct tracer *type = current_trace; | |
2f26ebd5 SR |
1818 | unsigned long entries = 0; |
1819 | unsigned long total = 0; | |
1820 | unsigned long count; | |
bc0c38d1 | 1821 | const char *name = "preemption"; |
2f26ebd5 | 1822 | int cpu; |
bc0c38d1 SR |
1823 | |
1824 | if (type) | |
1825 | name = type->name; | |
1826 | ||
2f26ebd5 SR |
1827 | |
1828 | for_each_tracing_cpu(cpu) { | |
1829 | count = ring_buffer_entries_cpu(tr->buffer, cpu); | |
1830 | /* | |
1831 | * If this buffer has skipped entries, then we hold all | |
1832 | * entries for the trace and we need to ignore the | |
1833 | * ones before the time stamp. | |
1834 | */ | |
1835 | if (tr->data[cpu]->skipped_entries) { | |
1836 | count -= tr->data[cpu]->skipped_entries; | |
1837 | /* total is the same as the entries */ | |
1838 | total += count; | |
1839 | } else | |
1840 | total += count + | |
1841 | ring_buffer_overrun_cpu(tr->buffer, cpu); | |
1842 | entries += count; | |
1843 | } | |
bc0c38d1 | 1844 | |
888b55dc | 1845 | seq_printf(m, "# %s latency trace v1.1.5 on %s\n", |
bc0c38d1 | 1846 | name, UTS_RELEASE); |
888b55dc | 1847 | seq_puts(m, "# -----------------------------------" |
bc0c38d1 | 1848 | "---------------------------------\n"); |
888b55dc | 1849 | seq_printf(m, "# latency: %lu us, #%lu/%lu, CPU#%d |" |
bc0c38d1 | 1850 | " (M:%s VP:%d, KP:%d, SP:%d HP:%d", |
57f50be1 | 1851 | nsecs_to_usecs(data->saved_latency), |
bc0c38d1 | 1852 | entries, |
4c11d7ae | 1853 | total, |
bc0c38d1 SR |
1854 | tr->cpu, |
1855 | #if defined(CONFIG_PREEMPT_NONE) | |
1856 | "server", | |
1857 | #elif defined(CONFIG_PREEMPT_VOLUNTARY) | |
1858 | "desktop", | |
b5c21b45 | 1859 | #elif defined(CONFIG_PREEMPT) |
bc0c38d1 SR |
1860 | "preempt", |
1861 | #else | |
1862 | "unknown", | |
1863 | #endif | |
1864 | /* These are reserved for later use */ | |
1865 | 0, 0, 0, 0); | |
1866 | #ifdef CONFIG_SMP | |
1867 | seq_printf(m, " #P:%d)\n", num_online_cpus()); | |
1868 | #else | |
1869 | seq_puts(m, ")\n"); | |
1870 | #endif | |
888b55dc KM |
1871 | seq_puts(m, "# -----------------\n"); |
1872 | seq_printf(m, "# | task: %.16s-%d " | |
bc0c38d1 SR |
1873 | "(uid:%d nice:%ld policy:%ld rt_prio:%ld)\n", |
1874 | data->comm, data->pid, data->uid, data->nice, | |
1875 | data->policy, data->rt_priority); | |
888b55dc | 1876 | seq_puts(m, "# -----------------\n"); |
bc0c38d1 SR |
1877 | |
1878 | if (data->critical_start) { | |
888b55dc | 1879 | seq_puts(m, "# => started at: "); |
214023c3 SR |
1880 | seq_print_ip_sym(&iter->seq, data->critical_start, sym_flags); |
1881 | trace_print_seq(m, &iter->seq); | |
888b55dc | 1882 | seq_puts(m, "\n# => ended at: "); |
214023c3 SR |
1883 | seq_print_ip_sym(&iter->seq, data->critical_end, sym_flags); |
1884 | trace_print_seq(m, &iter->seq); | |
8248ac05 | 1885 | seq_puts(m, "\n#\n"); |
bc0c38d1 SR |
1886 | } |
1887 | ||
888b55dc | 1888 | seq_puts(m, "#\n"); |
bc0c38d1 SR |
1889 | } |
1890 | ||
a309720c SR |
1891 | static void test_cpu_buff_start(struct trace_iterator *iter) |
1892 | { | |
1893 | struct trace_seq *s = &iter->seq; | |
1894 | ||
12ef7d44 SR |
1895 | if (!(trace_flags & TRACE_ITER_ANNOTATE)) |
1896 | return; | |
1897 | ||
1898 | if (!(iter->iter_flags & TRACE_FILE_ANNOTATE)) | |
1899 | return; | |
1900 | ||
4462344e | 1901 | if (cpumask_test_cpu(iter->cpu, iter->started)) |
a309720c SR |
1902 | return; |
1903 | ||
2f26ebd5 SR |
1904 | if (iter->tr->data[iter->cpu]->skipped_entries) |
1905 | return; | |
1906 | ||
4462344e | 1907 | cpumask_set_cpu(iter->cpu, iter->started); |
b0dfa978 FW |
1908 | |
1909 | /* Don't print started cpu buffer for the first entry of the trace */ | |
1910 | if (iter->idx > 1) | |
1911 | trace_seq_printf(s, "##### CPU %u buffer started ####\n", | |
1912 | iter->cpu); | |
a309720c SR |
1913 | } |
1914 | ||
2c4f035f | 1915 | static enum print_line_t print_trace_fmt(struct trace_iterator *iter) |
bc0c38d1 | 1916 | { |
214023c3 | 1917 | struct trace_seq *s = &iter->seq; |
bc0c38d1 | 1918 | unsigned long sym_flags = (trace_flags & TRACE_ITER_SYM_MASK); |
4e3c3333 | 1919 | struct trace_entry *entry; |
f633cef0 | 1920 | struct trace_event *event; |
bc0c38d1 | 1921 | |
4e3c3333 | 1922 | entry = iter->ent; |
dd0e545f | 1923 | |
a309720c SR |
1924 | test_cpu_buff_start(iter); |
1925 | ||
c4a8e8be | 1926 | event = ftrace_find_event(entry->type); |
bc0c38d1 | 1927 | |
c4a8e8be | 1928 | if (trace_flags & TRACE_ITER_CONTEXT_INFO) { |
27d48be8 SR |
1929 | if (iter->iter_flags & TRACE_FILE_LAT_FMT) { |
1930 | if (!trace_print_lat_context(iter)) | |
1931 | goto partial; | |
1932 | } else { | |
1933 | if (!trace_print_context(iter)) | |
1934 | goto partial; | |
1935 | } | |
c4a8e8be | 1936 | } |
bc0c38d1 | 1937 | |
268ccda0 | 1938 | if (event) |
d9793bd8 ACM |
1939 | return event->trace(iter, sym_flags); |
1940 | ||
1941 | if (!trace_seq_printf(s, "Unknown type %d\n", entry->type)) | |
1942 | goto partial; | |
02b67518 | 1943 | |
2c4f035f | 1944 | return TRACE_TYPE_HANDLED; |
d9793bd8 ACM |
1945 | partial: |
1946 | return TRACE_TYPE_PARTIAL_LINE; | |
bc0c38d1 SR |
1947 | } |
1948 | ||
2c4f035f | 1949 | static enum print_line_t print_raw_fmt(struct trace_iterator *iter) |
f9896bf3 IM |
1950 | { |
1951 | struct trace_seq *s = &iter->seq; | |
1952 | struct trace_entry *entry; | |
f633cef0 | 1953 | struct trace_event *event; |
f9896bf3 IM |
1954 | |
1955 | entry = iter->ent; | |
dd0e545f | 1956 | |
c4a8e8be | 1957 | if (trace_flags & TRACE_ITER_CONTEXT_INFO) { |
d9793bd8 ACM |
1958 | if (!trace_seq_printf(s, "%d %d %llu ", |
1959 | entry->pid, iter->cpu, iter->ts)) | |
1960 | goto partial; | |
c4a8e8be | 1961 | } |
f9896bf3 | 1962 | |
f633cef0 | 1963 | event = ftrace_find_event(entry->type); |
268ccda0 | 1964 | if (event) |
d9793bd8 ACM |
1965 | return event->raw(iter, 0); |
1966 | ||
1967 | if (!trace_seq_printf(s, "%d ?\n", entry->type)) | |
1968 | goto partial; | |
777e208d | 1969 | |
2c4f035f | 1970 | return TRACE_TYPE_HANDLED; |
d9793bd8 ACM |
1971 | partial: |
1972 | return TRACE_TYPE_PARTIAL_LINE; | |
f9896bf3 IM |
1973 | } |
1974 | ||
2c4f035f | 1975 | static enum print_line_t print_hex_fmt(struct trace_iterator *iter) |
5e3ca0ec IM |
1976 | { |
1977 | struct trace_seq *s = &iter->seq; | |
1978 | unsigned char newline = '\n'; | |
1979 | struct trace_entry *entry; | |
f633cef0 | 1980 | struct trace_event *event; |
5e3ca0ec IM |
1981 | |
1982 | entry = iter->ent; | |
dd0e545f | 1983 | |
c4a8e8be FW |
1984 | if (trace_flags & TRACE_ITER_CONTEXT_INFO) { |
1985 | SEQ_PUT_HEX_FIELD_RET(s, entry->pid); | |
1986 | SEQ_PUT_HEX_FIELD_RET(s, iter->cpu); | |
1987 | SEQ_PUT_HEX_FIELD_RET(s, iter->ts); | |
1988 | } | |
5e3ca0ec | 1989 | |
f633cef0 | 1990 | event = ftrace_find_event(entry->type); |
268ccda0 | 1991 | if (event) { |
ae7462b4 | 1992 | enum print_line_t ret = event->hex(iter, 0); |
d9793bd8 ACM |
1993 | if (ret != TRACE_TYPE_HANDLED) |
1994 | return ret; | |
1995 | } | |
7104f300 | 1996 | |
5e3ca0ec IM |
1997 | SEQ_PUT_FIELD_RET(s, newline); |
1998 | ||
2c4f035f | 1999 | return TRACE_TYPE_HANDLED; |
5e3ca0ec IM |
2000 | } |
2001 | ||
2c4f035f | 2002 | static enum print_line_t print_bin_fmt(struct trace_iterator *iter) |
cb0f12aa IM |
2003 | { |
2004 | struct trace_seq *s = &iter->seq; | |
2005 | struct trace_entry *entry; | |
f633cef0 | 2006 | struct trace_event *event; |
cb0f12aa IM |
2007 | |
2008 | entry = iter->ent; | |
dd0e545f | 2009 | |
c4a8e8be FW |
2010 | if (trace_flags & TRACE_ITER_CONTEXT_INFO) { |
2011 | SEQ_PUT_FIELD_RET(s, entry->pid); | |
1830b52d | 2012 | SEQ_PUT_FIELD_RET(s, iter->cpu); |
c4a8e8be FW |
2013 | SEQ_PUT_FIELD_RET(s, iter->ts); |
2014 | } | |
cb0f12aa | 2015 | |
f633cef0 | 2016 | event = ftrace_find_event(entry->type); |
268ccda0 | 2017 | return event ? event->binary(iter, 0) : TRACE_TYPE_HANDLED; |
cb0f12aa IM |
2018 | } |
2019 | ||
62b915f1 | 2020 | int trace_empty(struct trace_iterator *iter) |
bc0c38d1 | 2021 | { |
bc0c38d1 SR |
2022 | int cpu; |
2023 | ||
9aba60fe SR |
2024 | /* If we are looking at one CPU buffer, only check that one */ |
2025 | if (iter->cpu_file != TRACE_PIPE_ALL_CPU) { | |
2026 | cpu = iter->cpu_file; | |
2027 | if (iter->buffer_iter[cpu]) { | |
2028 | if (!ring_buffer_iter_empty(iter->buffer_iter[cpu])) | |
2029 | return 0; | |
2030 | } else { | |
2031 | if (!ring_buffer_empty_cpu(iter->tr->buffer, cpu)) | |
2032 | return 0; | |
2033 | } | |
2034 | return 1; | |
2035 | } | |
2036 | ||
ab46428c | 2037 | for_each_tracing_cpu(cpu) { |
d769041f SR |
2038 | if (iter->buffer_iter[cpu]) { |
2039 | if (!ring_buffer_iter_empty(iter->buffer_iter[cpu])) | |
2040 | return 0; | |
2041 | } else { | |
2042 | if (!ring_buffer_empty_cpu(iter->tr->buffer, cpu)) | |
2043 | return 0; | |
2044 | } | |
bc0c38d1 | 2045 | } |
d769041f | 2046 | |
797d3712 | 2047 | return 1; |
bc0c38d1 SR |
2048 | } |
2049 | ||
4f535968 | 2050 | /* Called with trace_event_read_lock() held. */ |
2c4f035f | 2051 | static enum print_line_t print_trace_line(struct trace_iterator *iter) |
f9896bf3 | 2052 | { |
2c4f035f FW |
2053 | enum print_line_t ret; |
2054 | ||
bc21b478 SR |
2055 | if (iter->lost_events) |
2056 | trace_seq_printf(&iter->seq, "CPU:%d [LOST %lu EVENTS]\n", | |
2057 | iter->cpu, iter->lost_events); | |
2058 | ||
2c4f035f FW |
2059 | if (iter->trace && iter->trace->print_line) { |
2060 | ret = iter->trace->print_line(iter); | |
2061 | if (ret != TRACE_TYPE_UNHANDLED) | |
2062 | return ret; | |
2063 | } | |
72829bc3 | 2064 | |
48ead020 FW |
2065 | if (iter->ent->type == TRACE_BPRINT && |
2066 | trace_flags & TRACE_ITER_PRINTK && | |
2067 | trace_flags & TRACE_ITER_PRINTK_MSGONLY) | |
5ef841f6 | 2068 | return trace_print_bprintk_msg_only(iter); |
48ead020 | 2069 | |
66896a85 FW |
2070 | if (iter->ent->type == TRACE_PRINT && |
2071 | trace_flags & TRACE_ITER_PRINTK && | |
2072 | trace_flags & TRACE_ITER_PRINTK_MSGONLY) | |
5ef841f6 | 2073 | return trace_print_printk_msg_only(iter); |
66896a85 | 2074 | |
cb0f12aa IM |
2075 | if (trace_flags & TRACE_ITER_BIN) |
2076 | return print_bin_fmt(iter); | |
2077 | ||
5e3ca0ec IM |
2078 | if (trace_flags & TRACE_ITER_HEX) |
2079 | return print_hex_fmt(iter); | |
2080 | ||
f9896bf3 IM |
2081 | if (trace_flags & TRACE_ITER_RAW) |
2082 | return print_raw_fmt(iter); | |
2083 | ||
f9896bf3 IM |
2084 | return print_trace_fmt(iter); |
2085 | } | |
2086 | ||
62b915f1 JO |
2087 | void trace_default_header(struct seq_file *m) |
2088 | { | |
2089 | struct trace_iterator *iter = m->private; | |
2090 | ||
2091 | if (iter->iter_flags & TRACE_FILE_LAT_FMT) { | |
2092 | /* print nothing if the buffers are empty */ | |
2093 | if (trace_empty(iter)) | |
2094 | return; | |
2095 | print_trace_header(m, iter); | |
2096 | if (!(trace_flags & TRACE_ITER_VERBOSE)) | |
2097 | print_lat_help_header(m); | |
2098 | } else { | |
2099 | if (!(trace_flags & TRACE_ITER_VERBOSE)) | |
2100 | print_func_help_header(m); | |
2101 | } | |
2102 | } | |
2103 | ||
bc0c38d1 SR |
2104 | static int s_show(struct seq_file *m, void *v) |
2105 | { | |
2106 | struct trace_iterator *iter = v; | |
a63ce5b3 | 2107 | int ret; |
bc0c38d1 SR |
2108 | |
2109 | if (iter->ent == NULL) { | |
2110 | if (iter->tr) { | |
2111 | seq_printf(m, "# tracer: %s\n", iter->trace->name); | |
2112 | seq_puts(m, "#\n"); | |
2113 | } | |
8bba1bf5 MM |
2114 | if (iter->trace && iter->trace->print_header) |
2115 | iter->trace->print_header(m); | |
62b915f1 JO |
2116 | else |
2117 | trace_default_header(m); | |
2118 | ||
a63ce5b3 SR |
2119 | } else if (iter->leftover) { |
2120 | /* | |
2121 | * If we filled the seq_file buffer earlier, we | |
2122 | * want to just show it now. | |
2123 | */ | |
2124 | ret = trace_print_seq(m, &iter->seq); | |
2125 | ||
2126 | /* ret should this time be zero, but you never know */ | |
2127 | iter->leftover = ret; | |
2128 | ||
bc0c38d1 | 2129 | } else { |
f9896bf3 | 2130 | print_trace_line(iter); |
a63ce5b3 SR |
2131 | ret = trace_print_seq(m, &iter->seq); |
2132 | /* | |
2133 | * If we overflow the seq_file buffer, then it will | |
2134 | * ask us for this data again at start up. | |
2135 | * Use that instead. | |
2136 | * ret is 0 if seq_file write succeeded. | |
2137 | * -1 otherwise. | |
2138 | */ | |
2139 | iter->leftover = ret; | |
bc0c38d1 SR |
2140 | } |
2141 | ||
2142 | return 0; | |
2143 | } | |
2144 | ||
88e9d34c | 2145 | static const struct seq_operations tracer_seq_ops = { |
4bf39a94 IM |
2146 | .start = s_start, |
2147 | .next = s_next, | |
2148 | .stop = s_stop, | |
2149 | .show = s_show, | |
bc0c38d1 SR |
2150 | }; |
2151 | ||
e309b41d | 2152 | static struct trace_iterator * |
85a2f9b4 | 2153 | __tracing_open(struct inode *inode, struct file *file) |
bc0c38d1 | 2154 | { |
b04cc6b1 | 2155 | long cpu_file = (long) inode->i_private; |
85a2f9b4 | 2156 | void *fail_ret = ERR_PTR(-ENOMEM); |
bc0c38d1 | 2157 | struct trace_iterator *iter; |
3928a8a2 | 2158 | struct seq_file *m; |
85a2f9b4 | 2159 | int cpu, ret; |
bc0c38d1 | 2160 | |
85a2f9b4 SR |
2161 | if (tracing_disabled) |
2162 | return ERR_PTR(-ENODEV); | |
60a11774 | 2163 | |
bc0c38d1 | 2164 | iter = kzalloc(sizeof(*iter), GFP_KERNEL); |
85a2f9b4 SR |
2165 | if (!iter) |
2166 | return ERR_PTR(-ENOMEM); | |
bc0c38d1 | 2167 | |
d7350c3f FW |
2168 | /* |
2169 | * We make a copy of the current tracer to avoid concurrent | |
2170 | * changes on it while we are reading. | |
2171 | */ | |
bc0c38d1 | 2172 | mutex_lock(&trace_types_lock); |
d7350c3f | 2173 | iter->trace = kzalloc(sizeof(*iter->trace), GFP_KERNEL); |
85a2f9b4 | 2174 | if (!iter->trace) |
d7350c3f | 2175 | goto fail; |
85a2f9b4 | 2176 | |
d7350c3f FW |
2177 | if (current_trace) |
2178 | *iter->trace = *current_trace; | |
2179 | ||
79f55997 | 2180 | if (!zalloc_cpumask_var(&iter->started, GFP_KERNEL)) |
b0dfa978 FW |
2181 | goto fail; |
2182 | ||
bc0c38d1 SR |
2183 | if (current_trace && current_trace->print_max) |
2184 | iter->tr = &max_tr; | |
2185 | else | |
b04cc6b1 | 2186 | iter->tr = &global_trace; |
bc0c38d1 | 2187 | iter->pos = -1; |
d7350c3f | 2188 | mutex_init(&iter->mutex); |
b04cc6b1 | 2189 | iter->cpu_file = cpu_file; |
bc0c38d1 | 2190 | |
8bba1bf5 MM |
2191 | /* Notify the tracer early; before we stop tracing. */ |
2192 | if (iter->trace && iter->trace->open) | |
a93751ca | 2193 | iter->trace->open(iter); |
8bba1bf5 | 2194 | |
12ef7d44 SR |
2195 | /* Annotate start of buffers if we had overruns */ |
2196 | if (ring_buffer_overruns(iter->tr->buffer)) | |
2197 | iter->iter_flags |= TRACE_FILE_ANNOTATE; | |
2198 | ||
2f26ebd5 SR |
2199 | /* stop the trace while dumping */ |
2200 | tracing_stop(); | |
2201 | ||
b04cc6b1 FW |
2202 | if (iter->cpu_file == TRACE_PIPE_ALL_CPU) { |
2203 | for_each_tracing_cpu(cpu) { | |
b04cc6b1 | 2204 | iter->buffer_iter[cpu] = |
72c9ddfd DM |
2205 | ring_buffer_read_prepare(iter->tr->buffer, cpu); |
2206 | } | |
2207 | ring_buffer_read_prepare_sync(); | |
2208 | for_each_tracing_cpu(cpu) { | |
2209 | ring_buffer_read_start(iter->buffer_iter[cpu]); | |
2f26ebd5 | 2210 | tracing_iter_reset(iter, cpu); |
b04cc6b1 FW |
2211 | } |
2212 | } else { | |
2213 | cpu = iter->cpu_file; | |
3928a8a2 | 2214 | iter->buffer_iter[cpu] = |
72c9ddfd DM |
2215 | ring_buffer_read_prepare(iter->tr->buffer, cpu); |
2216 | ring_buffer_read_prepare_sync(); | |
2217 | ring_buffer_read_start(iter->buffer_iter[cpu]); | |
2f26ebd5 | 2218 | tracing_iter_reset(iter, cpu); |
3928a8a2 SR |
2219 | } |
2220 | ||
85a2f9b4 SR |
2221 | ret = seq_open(file, &tracer_seq_ops); |
2222 | if (ret < 0) { | |
2223 | fail_ret = ERR_PTR(ret); | |
3928a8a2 | 2224 | goto fail_buffer; |
85a2f9b4 | 2225 | } |
bc0c38d1 | 2226 | |
3928a8a2 SR |
2227 | m = file->private_data; |
2228 | m->private = iter; | |
bc0c38d1 | 2229 | |
bc0c38d1 SR |
2230 | mutex_unlock(&trace_types_lock); |
2231 | ||
bc0c38d1 | 2232 | return iter; |
3928a8a2 SR |
2233 | |
2234 | fail_buffer: | |
2235 | for_each_tracing_cpu(cpu) { | |
2236 | if (iter->buffer_iter[cpu]) | |
2237 | ring_buffer_read_finish(iter->buffer_iter[cpu]); | |
2238 | } | |
b0dfa978 | 2239 | free_cpumask_var(iter->started); |
2f26ebd5 | 2240 | tracing_start(); |
d7350c3f | 2241 | fail: |
3928a8a2 | 2242 | mutex_unlock(&trace_types_lock); |
d7350c3f | 2243 | kfree(iter->trace); |
0bb943c7 | 2244 | kfree(iter); |
3928a8a2 | 2245 | |
85a2f9b4 | 2246 | return fail_ret; |
bc0c38d1 SR |
2247 | } |
2248 | ||
2249 | int tracing_open_generic(struct inode *inode, struct file *filp) | |
2250 | { | |
60a11774 SR |
2251 | if (tracing_disabled) |
2252 | return -ENODEV; | |
2253 | ||
bc0c38d1 SR |
2254 | filp->private_data = inode->i_private; |
2255 | return 0; | |
2256 | } | |
2257 | ||
4fd27358 | 2258 | static int tracing_release(struct inode *inode, struct file *file) |
bc0c38d1 SR |
2259 | { |
2260 | struct seq_file *m = (struct seq_file *)file->private_data; | |
4acd4d00 | 2261 | struct trace_iterator *iter; |
3928a8a2 | 2262 | int cpu; |
bc0c38d1 | 2263 | |
4acd4d00 SR |
2264 | if (!(file->f_mode & FMODE_READ)) |
2265 | return 0; | |
2266 | ||
2267 | iter = m->private; | |
2268 | ||
bc0c38d1 | 2269 | mutex_lock(&trace_types_lock); |
3928a8a2 SR |
2270 | for_each_tracing_cpu(cpu) { |
2271 | if (iter->buffer_iter[cpu]) | |
2272 | ring_buffer_read_finish(iter->buffer_iter[cpu]); | |
2273 | } | |
2274 | ||
bc0c38d1 SR |
2275 | if (iter->trace && iter->trace->close) |
2276 | iter->trace->close(iter); | |
2277 | ||
2278 | /* reenable tracing if it was previously enabled */ | |
9036990d | 2279 | tracing_start(); |
bc0c38d1 SR |
2280 | mutex_unlock(&trace_types_lock); |
2281 | ||
2282 | seq_release(inode, file); | |
d7350c3f | 2283 | mutex_destroy(&iter->mutex); |
b0dfa978 | 2284 | free_cpumask_var(iter->started); |
d7350c3f | 2285 | kfree(iter->trace); |
bc0c38d1 SR |
2286 | kfree(iter); |
2287 | return 0; | |
2288 | } | |
2289 | ||
2290 | static int tracing_open(struct inode *inode, struct file *file) | |
2291 | { | |
85a2f9b4 SR |
2292 | struct trace_iterator *iter; |
2293 | int ret = 0; | |
bc0c38d1 | 2294 | |
4acd4d00 SR |
2295 | /* If this file was open for write, then erase contents */ |
2296 | if ((file->f_mode & FMODE_WRITE) && | |
8650ae32 | 2297 | (file->f_flags & O_TRUNC)) { |
4acd4d00 | 2298 | long cpu = (long) inode->i_private; |
bc0c38d1 | 2299 | |
4acd4d00 SR |
2300 | if (cpu == TRACE_PIPE_ALL_CPU) |
2301 | tracing_reset_online_cpus(&global_trace); | |
2302 | else | |
2303 | tracing_reset(&global_trace, cpu); | |
2304 | } | |
bc0c38d1 | 2305 | |
4acd4d00 SR |
2306 | if (file->f_mode & FMODE_READ) { |
2307 | iter = __tracing_open(inode, file); | |
2308 | if (IS_ERR(iter)) | |
2309 | ret = PTR_ERR(iter); | |
2310 | else if (trace_flags & TRACE_ITER_LATENCY_FMT) | |
2311 | iter->iter_flags |= TRACE_FILE_LAT_FMT; | |
2312 | } | |
bc0c38d1 SR |
2313 | return ret; |
2314 | } | |
2315 | ||
e309b41d | 2316 | static void * |
bc0c38d1 SR |
2317 | t_next(struct seq_file *m, void *v, loff_t *pos) |
2318 | { | |
f129e965 | 2319 | struct tracer *t = v; |
bc0c38d1 SR |
2320 | |
2321 | (*pos)++; | |
2322 | ||
2323 | if (t) | |
2324 | t = t->next; | |
2325 | ||
bc0c38d1 SR |
2326 | return t; |
2327 | } | |
2328 | ||
2329 | static void *t_start(struct seq_file *m, loff_t *pos) | |
2330 | { | |
f129e965 | 2331 | struct tracer *t; |
bc0c38d1 SR |
2332 | loff_t l = 0; |
2333 | ||
2334 | mutex_lock(&trace_types_lock); | |
f129e965 | 2335 | for (t = trace_types; t && l < *pos; t = t_next(m, t, &l)) |
bc0c38d1 SR |
2336 | ; |
2337 | ||
2338 | return t; | |
2339 | } | |
2340 | ||
2341 | static void t_stop(struct seq_file *m, void *p) | |
2342 | { | |
2343 | mutex_unlock(&trace_types_lock); | |
2344 | } | |
2345 | ||
2346 | static int t_show(struct seq_file *m, void *v) | |
2347 | { | |
2348 | struct tracer *t = v; | |
2349 | ||
2350 | if (!t) | |
2351 | return 0; | |
2352 | ||
2353 | seq_printf(m, "%s", t->name); | |
2354 | if (t->next) | |
2355 | seq_putc(m, ' '); | |
2356 | else | |
2357 | seq_putc(m, '\n'); | |
2358 | ||
2359 | return 0; | |
2360 | } | |
2361 | ||
88e9d34c | 2362 | static const struct seq_operations show_traces_seq_ops = { |
4bf39a94 IM |
2363 | .start = t_start, |
2364 | .next = t_next, | |
2365 | .stop = t_stop, | |
2366 | .show = t_show, | |
bc0c38d1 SR |
2367 | }; |
2368 | ||
2369 | static int show_traces_open(struct inode *inode, struct file *file) | |
2370 | { | |
60a11774 SR |
2371 | if (tracing_disabled) |
2372 | return -ENODEV; | |
2373 | ||
f129e965 | 2374 | return seq_open(file, &show_traces_seq_ops); |
bc0c38d1 SR |
2375 | } |
2376 | ||
4acd4d00 SR |
2377 | static ssize_t |
2378 | tracing_write_stub(struct file *filp, const char __user *ubuf, | |
2379 | size_t count, loff_t *ppos) | |
2380 | { | |
2381 | return count; | |
2382 | } | |
2383 | ||
5e2336a0 | 2384 | static const struct file_operations tracing_fops = { |
4bf39a94 IM |
2385 | .open = tracing_open, |
2386 | .read = seq_read, | |
4acd4d00 | 2387 | .write = tracing_write_stub, |
4bf39a94 IM |
2388 | .llseek = seq_lseek, |
2389 | .release = tracing_release, | |
bc0c38d1 SR |
2390 | }; |
2391 | ||
5e2336a0 | 2392 | static const struct file_operations show_traces_fops = { |
c7078de1 IM |
2393 | .open = show_traces_open, |
2394 | .read = seq_read, | |
2395 | .release = seq_release, | |
2396 | }; | |
2397 | ||
36dfe925 IM |
2398 | /* |
2399 | * Only trace on a CPU if the bitmask is set: | |
2400 | */ | |
9e01c1b7 | 2401 | static cpumask_var_t tracing_cpumask; |
36dfe925 IM |
2402 | |
2403 | /* | |
2404 | * The tracer itself will not take this lock, but still we want | |
2405 | * to provide a consistent cpumask to user-space: | |
2406 | */ | |
2407 | static DEFINE_MUTEX(tracing_cpumask_update_lock); | |
2408 | ||
2409 | /* | |
2410 | * Temporary storage for the character representation of the | |
2411 | * CPU bitmask (and one more byte for the newline): | |
2412 | */ | |
2413 | static char mask_str[NR_CPUS + 1]; | |
2414 | ||
c7078de1 IM |
2415 | static ssize_t |
2416 | tracing_cpumask_read(struct file *filp, char __user *ubuf, | |
2417 | size_t count, loff_t *ppos) | |
2418 | { | |
36dfe925 | 2419 | int len; |
c7078de1 IM |
2420 | |
2421 | mutex_lock(&tracing_cpumask_update_lock); | |
36dfe925 | 2422 | |
9e01c1b7 | 2423 | len = cpumask_scnprintf(mask_str, count, tracing_cpumask); |
36dfe925 IM |
2424 | if (count - len < 2) { |
2425 | count = -EINVAL; | |
2426 | goto out_err; | |
2427 | } | |
2428 | len += sprintf(mask_str + len, "\n"); | |
2429 | count = simple_read_from_buffer(ubuf, count, ppos, mask_str, NR_CPUS+1); | |
2430 | ||
2431 | out_err: | |
c7078de1 IM |
2432 | mutex_unlock(&tracing_cpumask_update_lock); |
2433 | ||
2434 | return count; | |
2435 | } | |
2436 | ||
2437 | static ssize_t | |
2438 | tracing_cpumask_write(struct file *filp, const char __user *ubuf, | |
2439 | size_t count, loff_t *ppos) | |
2440 | { | |
36dfe925 | 2441 | int err, cpu; |
9e01c1b7 RR |
2442 | cpumask_var_t tracing_cpumask_new; |
2443 | ||
2444 | if (!alloc_cpumask_var(&tracing_cpumask_new, GFP_KERNEL)) | |
2445 | return -ENOMEM; | |
c7078de1 | 2446 | |
9e01c1b7 | 2447 | err = cpumask_parse_user(ubuf, count, tracing_cpumask_new); |
c7078de1 | 2448 | if (err) |
36dfe925 IM |
2449 | goto err_unlock; |
2450 | ||
215368e8 LZ |
2451 | mutex_lock(&tracing_cpumask_update_lock); |
2452 | ||
a5e25883 | 2453 | local_irq_disable(); |
0199c4e6 | 2454 | arch_spin_lock(&ftrace_max_lock); |
ab46428c | 2455 | for_each_tracing_cpu(cpu) { |
36dfe925 IM |
2456 | /* |
2457 | * Increase/decrease the disabled counter if we are | |
2458 | * about to flip a bit in the cpumask: | |
2459 | */ | |
9e01c1b7 RR |
2460 | if (cpumask_test_cpu(cpu, tracing_cpumask) && |
2461 | !cpumask_test_cpu(cpu, tracing_cpumask_new)) { | |
36dfe925 IM |
2462 | atomic_inc(&global_trace.data[cpu]->disabled); |
2463 | } | |
9e01c1b7 RR |
2464 | if (!cpumask_test_cpu(cpu, tracing_cpumask) && |
2465 | cpumask_test_cpu(cpu, tracing_cpumask_new)) { | |
36dfe925 IM |
2466 | atomic_dec(&global_trace.data[cpu]->disabled); |
2467 | } | |
2468 | } | |
0199c4e6 | 2469 | arch_spin_unlock(&ftrace_max_lock); |
a5e25883 | 2470 | local_irq_enable(); |
36dfe925 | 2471 | |
9e01c1b7 | 2472 | cpumask_copy(tracing_cpumask, tracing_cpumask_new); |
36dfe925 IM |
2473 | |
2474 | mutex_unlock(&tracing_cpumask_update_lock); | |
9e01c1b7 | 2475 | free_cpumask_var(tracing_cpumask_new); |
c7078de1 IM |
2476 | |
2477 | return count; | |
36dfe925 IM |
2478 | |
2479 | err_unlock: | |
215368e8 | 2480 | free_cpumask_var(tracing_cpumask_new); |
36dfe925 IM |
2481 | |
2482 | return err; | |
c7078de1 IM |
2483 | } |
2484 | ||
5e2336a0 | 2485 | static const struct file_operations tracing_cpumask_fops = { |
c7078de1 IM |
2486 | .open = tracing_open_generic, |
2487 | .read = tracing_cpumask_read, | |
2488 | .write = tracing_cpumask_write, | |
bc0c38d1 SR |
2489 | }; |
2490 | ||
fdb372ed | 2491 | static int tracing_trace_options_show(struct seq_file *m, void *v) |
bc0c38d1 | 2492 | { |
d8e83d26 SR |
2493 | struct tracer_opt *trace_opts; |
2494 | u32 tracer_flags; | |
d8e83d26 | 2495 | int i; |
adf9f195 | 2496 | |
d8e83d26 SR |
2497 | mutex_lock(&trace_types_lock); |
2498 | tracer_flags = current_trace->flags->val; | |
2499 | trace_opts = current_trace->flags->opts; | |
2500 | ||
bc0c38d1 SR |
2501 | for (i = 0; trace_options[i]; i++) { |
2502 | if (trace_flags & (1 << i)) | |
fdb372ed | 2503 | seq_printf(m, "%s\n", trace_options[i]); |
bc0c38d1 | 2504 | else |
fdb372ed | 2505 | seq_printf(m, "no%s\n", trace_options[i]); |
bc0c38d1 SR |
2506 | } |
2507 | ||
adf9f195 FW |
2508 | for (i = 0; trace_opts[i].name; i++) { |
2509 | if (tracer_flags & trace_opts[i].bit) | |
fdb372ed | 2510 | seq_printf(m, "%s\n", trace_opts[i].name); |
adf9f195 | 2511 | else |
fdb372ed | 2512 | seq_printf(m, "no%s\n", trace_opts[i].name); |
adf9f195 | 2513 | } |
d8e83d26 | 2514 | mutex_unlock(&trace_types_lock); |
adf9f195 | 2515 | |
fdb372ed | 2516 | return 0; |
bc0c38d1 | 2517 | } |
bc0c38d1 | 2518 | |
8d18eaaf LZ |
2519 | static int __set_tracer_option(struct tracer *trace, |
2520 | struct tracer_flags *tracer_flags, | |
2521 | struct tracer_opt *opts, int neg) | |
2522 | { | |
2523 | int ret; | |
bc0c38d1 | 2524 | |
8d18eaaf LZ |
2525 | ret = trace->set_flag(tracer_flags->val, opts->bit, !neg); |
2526 | if (ret) | |
2527 | return ret; | |
2528 | ||
2529 | if (neg) | |
2530 | tracer_flags->val &= ~opts->bit; | |
2531 | else | |
2532 | tracer_flags->val |= opts->bit; | |
2533 | return 0; | |
bc0c38d1 SR |
2534 | } |
2535 | ||
adf9f195 FW |
2536 | /* Try to assign a tracer specific option */ |
2537 | static int set_tracer_option(struct tracer *trace, char *cmp, int neg) | |
2538 | { | |
7770841e | 2539 | struct tracer_flags *tracer_flags = trace->flags; |
adf9f195 | 2540 | struct tracer_opt *opts = NULL; |
8d18eaaf | 2541 | int i; |
adf9f195 | 2542 | |
7770841e Z |
2543 | for (i = 0; tracer_flags->opts[i].name; i++) { |
2544 | opts = &tracer_flags->opts[i]; | |
adf9f195 | 2545 | |
8d18eaaf LZ |
2546 | if (strcmp(cmp, opts->name) == 0) |
2547 | return __set_tracer_option(trace, trace->flags, | |
2548 | opts, neg); | |
adf9f195 | 2549 | } |
adf9f195 | 2550 | |
8d18eaaf | 2551 | return -EINVAL; |
adf9f195 FW |
2552 | } |
2553 | ||
af4617bd SR |
2554 | static void set_tracer_flags(unsigned int mask, int enabled) |
2555 | { | |
2556 | /* do nothing if flag is already set */ | |
2557 | if (!!(trace_flags & mask) == !!enabled) | |
2558 | return; | |
2559 | ||
2560 | if (enabled) | |
2561 | trace_flags |= mask; | |
2562 | else | |
2563 | trace_flags &= ~mask; | |
af4617bd SR |
2564 | } |
2565 | ||
bc0c38d1 | 2566 | static ssize_t |
ee6bce52 | 2567 | tracing_trace_options_write(struct file *filp, const char __user *ubuf, |
bc0c38d1 SR |
2568 | size_t cnt, loff_t *ppos) |
2569 | { | |
2570 | char buf[64]; | |
8d18eaaf | 2571 | char *cmp; |
bc0c38d1 | 2572 | int neg = 0; |
adf9f195 | 2573 | int ret; |
bc0c38d1 SR |
2574 | int i; |
2575 | ||
cffae437 SR |
2576 | if (cnt >= sizeof(buf)) |
2577 | return -EINVAL; | |
bc0c38d1 SR |
2578 | |
2579 | if (copy_from_user(&buf, ubuf, cnt)) | |
2580 | return -EFAULT; | |
2581 | ||
2582 | buf[cnt] = 0; | |
8d18eaaf | 2583 | cmp = strstrip(buf); |
bc0c38d1 | 2584 | |
8d18eaaf | 2585 | if (strncmp(cmp, "no", 2) == 0) { |
bc0c38d1 SR |
2586 | neg = 1; |
2587 | cmp += 2; | |
2588 | } | |
2589 | ||
2590 | for (i = 0; trace_options[i]; i++) { | |
8d18eaaf | 2591 | if (strcmp(cmp, trace_options[i]) == 0) { |
af4617bd | 2592 | set_tracer_flags(1 << i, !neg); |
bc0c38d1 SR |
2593 | break; |
2594 | } | |
2595 | } | |
adf9f195 FW |
2596 | |
2597 | /* If no option could be set, test the specific tracer options */ | |
2598 | if (!trace_options[i]) { | |
d8e83d26 | 2599 | mutex_lock(&trace_types_lock); |
adf9f195 | 2600 | ret = set_tracer_option(current_trace, cmp, neg); |
d8e83d26 | 2601 | mutex_unlock(&trace_types_lock); |
adf9f195 FW |
2602 | if (ret) |
2603 | return ret; | |
2604 | } | |
bc0c38d1 | 2605 | |
cf8517cf | 2606 | *ppos += cnt; |
bc0c38d1 SR |
2607 | |
2608 | return cnt; | |
2609 | } | |
2610 | ||
fdb372ed LZ |
2611 | static int tracing_trace_options_open(struct inode *inode, struct file *file) |
2612 | { | |
2613 | if (tracing_disabled) | |
2614 | return -ENODEV; | |
2615 | return single_open(file, tracing_trace_options_show, NULL); | |
2616 | } | |
2617 | ||
5e2336a0 | 2618 | static const struct file_operations tracing_iter_fops = { |
fdb372ed LZ |
2619 | .open = tracing_trace_options_open, |
2620 | .read = seq_read, | |
2621 | .llseek = seq_lseek, | |
2622 | .release = single_release, | |
ee6bce52 | 2623 | .write = tracing_trace_options_write, |
bc0c38d1 SR |
2624 | }; |
2625 | ||
7bd2f24c IM |
2626 | static const char readme_msg[] = |
2627 | "tracing mini-HOWTO:\n\n" | |
156f5a78 GL |
2628 | "# mount -t debugfs nodev /sys/kernel/debug\n\n" |
2629 | "# cat /sys/kernel/debug/tracing/available_tracers\n" | |
bc2b6871 | 2630 | "wakeup preemptirqsoff preemptoff irqsoff function sched_switch nop\n\n" |
156f5a78 | 2631 | "# cat /sys/kernel/debug/tracing/current_tracer\n" |
bc2b6871 | 2632 | "nop\n" |
156f5a78 GL |
2633 | "# echo sched_switch > /sys/kernel/debug/tracing/current_tracer\n" |
2634 | "# cat /sys/kernel/debug/tracing/current_tracer\n" | |
7bd2f24c | 2635 | "sched_switch\n" |
156f5a78 | 2636 | "# cat /sys/kernel/debug/tracing/trace_options\n" |
7bd2f24c | 2637 | "noprint-parent nosym-offset nosym-addr noverbose\n" |
156f5a78 GL |
2638 | "# echo print-parent > /sys/kernel/debug/tracing/trace_options\n" |
2639 | "# echo 1 > /sys/kernel/debug/tracing/tracing_enabled\n" | |
2640 | "# cat /sys/kernel/debug/tracing/trace > /tmp/trace.txt\n" | |
2641 | "# echo 0 > /sys/kernel/debug/tracing/tracing_enabled\n" | |
7bd2f24c IM |
2642 | ; |
2643 | ||
2644 | static ssize_t | |
2645 | tracing_readme_read(struct file *filp, char __user *ubuf, | |
2646 | size_t cnt, loff_t *ppos) | |
2647 | { | |
2648 | return simple_read_from_buffer(ubuf, cnt, ppos, | |
2649 | readme_msg, strlen(readme_msg)); | |
2650 | } | |
2651 | ||
5e2336a0 | 2652 | static const struct file_operations tracing_readme_fops = { |
c7078de1 IM |
2653 | .open = tracing_open_generic, |
2654 | .read = tracing_readme_read, | |
7bd2f24c IM |
2655 | }; |
2656 | ||
69abe6a5 AP |
2657 | static ssize_t |
2658 | tracing_saved_cmdlines_read(struct file *file, char __user *ubuf, | |
2659 | size_t cnt, loff_t *ppos) | |
2660 | { | |
2661 | char *buf_comm; | |
2662 | char *file_buf; | |
2663 | char *buf; | |
2664 | int len = 0; | |
2665 | int pid; | |
2666 | int i; | |
2667 | ||
2668 | file_buf = kmalloc(SAVED_CMDLINES*(16+TASK_COMM_LEN), GFP_KERNEL); | |
2669 | if (!file_buf) | |
2670 | return -ENOMEM; | |
2671 | ||
2672 | buf_comm = kmalloc(TASK_COMM_LEN, GFP_KERNEL); | |
2673 | if (!buf_comm) { | |
2674 | kfree(file_buf); | |
2675 | return -ENOMEM; | |
2676 | } | |
2677 | ||
2678 | buf = file_buf; | |
2679 | ||
2680 | for (i = 0; i < SAVED_CMDLINES; i++) { | |
2681 | int r; | |
2682 | ||
2683 | pid = map_cmdline_to_pid[i]; | |
2684 | if (pid == -1 || pid == NO_CMDLINE_MAP) | |
2685 | continue; | |
2686 | ||
2687 | trace_find_cmdline(pid, buf_comm); | |
2688 | r = sprintf(buf, "%d %s\n", pid, buf_comm); | |
2689 | buf += r; | |
2690 | len += r; | |
2691 | } | |
2692 | ||
2693 | len = simple_read_from_buffer(ubuf, cnt, ppos, | |
2694 | file_buf, len); | |
2695 | ||
2696 | kfree(file_buf); | |
2697 | kfree(buf_comm); | |
2698 | ||
2699 | return len; | |
2700 | } | |
2701 | ||
2702 | static const struct file_operations tracing_saved_cmdlines_fops = { | |
2703 | .open = tracing_open_generic, | |
2704 | .read = tracing_saved_cmdlines_read, | |
2705 | }; | |
2706 | ||
bc0c38d1 SR |
2707 | static ssize_t |
2708 | tracing_ctrl_read(struct file *filp, char __user *ubuf, | |
2709 | size_t cnt, loff_t *ppos) | |
2710 | { | |
bc0c38d1 SR |
2711 | char buf[64]; |
2712 | int r; | |
2713 | ||
9036990d | 2714 | r = sprintf(buf, "%u\n", tracer_enabled); |
4e3c3333 | 2715 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, r); |
bc0c38d1 SR |
2716 | } |
2717 | ||
2718 | static ssize_t | |
2719 | tracing_ctrl_write(struct file *filp, const char __user *ubuf, | |
2720 | size_t cnt, loff_t *ppos) | |
2721 | { | |
2722 | struct trace_array *tr = filp->private_data; | |
bc0c38d1 | 2723 | char buf[64]; |
5e39841c | 2724 | unsigned long val; |
c6caeeb1 | 2725 | int ret; |
bc0c38d1 | 2726 | |
cffae437 SR |
2727 | if (cnt >= sizeof(buf)) |
2728 | return -EINVAL; | |
bc0c38d1 SR |
2729 | |
2730 | if (copy_from_user(&buf, ubuf, cnt)) | |
2731 | return -EFAULT; | |
2732 | ||
2733 | buf[cnt] = 0; | |
2734 | ||
c6caeeb1 SR |
2735 | ret = strict_strtoul(buf, 10, &val); |
2736 | if (ret < 0) | |
2737 | return ret; | |
bc0c38d1 SR |
2738 | |
2739 | val = !!val; | |
2740 | ||
2741 | mutex_lock(&trace_types_lock); | |
9036990d SR |
2742 | if (tracer_enabled ^ val) { |
2743 | if (val) { | |
bc0c38d1 | 2744 | tracer_enabled = 1; |
9036990d SR |
2745 | if (current_trace->start) |
2746 | current_trace->start(tr); | |
2747 | tracing_start(); | |
2748 | } else { | |
bc0c38d1 | 2749 | tracer_enabled = 0; |
9036990d SR |
2750 | tracing_stop(); |
2751 | if (current_trace->stop) | |
2752 | current_trace->stop(tr); | |
2753 | } | |
bc0c38d1 SR |
2754 | } |
2755 | mutex_unlock(&trace_types_lock); | |
2756 | ||
cf8517cf | 2757 | *ppos += cnt; |
bc0c38d1 SR |
2758 | |
2759 | return cnt; | |
2760 | } | |
2761 | ||
2762 | static ssize_t | |
2763 | tracing_set_trace_read(struct file *filp, char __user *ubuf, | |
2764 | size_t cnt, loff_t *ppos) | |
2765 | { | |
ee6c2c1b | 2766 | char buf[MAX_TRACER_SIZE+2]; |
bc0c38d1 SR |
2767 | int r; |
2768 | ||
2769 | mutex_lock(&trace_types_lock); | |
2770 | if (current_trace) | |
2771 | r = sprintf(buf, "%s\n", current_trace->name); | |
2772 | else | |
2773 | r = sprintf(buf, "\n"); | |
2774 | mutex_unlock(&trace_types_lock); | |
2775 | ||
4bf39a94 | 2776 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, r); |
bc0c38d1 SR |
2777 | } |
2778 | ||
b6f11df2 ACM |
2779 | int tracer_init(struct tracer *t, struct trace_array *tr) |
2780 | { | |
2781 | tracing_reset_online_cpus(tr); | |
2782 | return t->init(tr); | |
2783 | } | |
2784 | ||
73c5162a SR |
2785 | static int tracing_resize_ring_buffer(unsigned long size) |
2786 | { | |
2787 | int ret; | |
2788 | ||
2789 | /* | |
2790 | * If kernel or user changes the size of the ring buffer | |
a123c52b SR |
2791 | * we use the size that was given, and we can forget about |
2792 | * expanding it later. | |
73c5162a SR |
2793 | */ |
2794 | ring_buffer_expanded = 1; | |
2795 | ||
2796 | ret = ring_buffer_resize(global_trace.buffer, size); | |
2797 | if (ret < 0) | |
2798 | return ret; | |
2799 | ||
2800 | ret = ring_buffer_resize(max_tr.buffer, size); | |
2801 | if (ret < 0) { | |
2802 | int r; | |
2803 | ||
2804 | r = ring_buffer_resize(global_trace.buffer, | |
2805 | global_trace.entries); | |
2806 | if (r < 0) { | |
a123c52b SR |
2807 | /* |
2808 | * AARGH! We are left with different | |
2809 | * size max buffer!!!! | |
2810 | * The max buffer is our "snapshot" buffer. | |
2811 | * When a tracer needs a snapshot (one of the | |
2812 | * latency tracers), it swaps the max buffer | |
2813 | * with the saved snap shot. We succeeded to | |
2814 | * update the size of the main buffer, but failed to | |
2815 | * update the size of the max buffer. But when we tried | |
2816 | * to reset the main buffer to the original size, we | |
2817 | * failed there too. This is very unlikely to | |
2818 | * happen, but if it does, warn and kill all | |
2819 | * tracing. | |
2820 | */ | |
73c5162a SR |
2821 | WARN_ON(1); |
2822 | tracing_disabled = 1; | |
2823 | } | |
2824 | return ret; | |
2825 | } | |
2826 | ||
2827 | global_trace.entries = size; | |
2828 | ||
2829 | return ret; | |
2830 | } | |
2831 | ||
1852fcce SR |
2832 | /** |
2833 | * tracing_update_buffers - used by tracing facility to expand ring buffers | |
2834 | * | |
2835 | * To save on memory when the tracing is never used on a system with it | |
2836 | * configured in. The ring buffers are set to a minimum size. But once | |
2837 | * a user starts to use the tracing facility, then they need to grow | |
2838 | * to their default size. | |
2839 | * | |
2840 | * This function is to be called when a tracer is about to be used. | |
2841 | */ | |
2842 | int tracing_update_buffers(void) | |
2843 | { | |
2844 | int ret = 0; | |
2845 | ||
1027fcb2 | 2846 | mutex_lock(&trace_types_lock); |
1852fcce SR |
2847 | if (!ring_buffer_expanded) |
2848 | ret = tracing_resize_ring_buffer(trace_buf_size); | |
1027fcb2 | 2849 | mutex_unlock(&trace_types_lock); |
1852fcce SR |
2850 | |
2851 | return ret; | |
2852 | } | |
2853 | ||
577b785f SR |
2854 | struct trace_option_dentry; |
2855 | ||
2856 | static struct trace_option_dentry * | |
2857 | create_trace_option_files(struct tracer *tracer); | |
2858 | ||
2859 | static void | |
2860 | destroy_trace_option_files(struct trace_option_dentry *topts); | |
2861 | ||
b2821ae6 | 2862 | static int tracing_set_tracer(const char *buf) |
bc0c38d1 | 2863 | { |
577b785f | 2864 | static struct trace_option_dentry *topts; |
bc0c38d1 SR |
2865 | struct trace_array *tr = &global_trace; |
2866 | struct tracer *t; | |
d9e54076 | 2867 | int ret = 0; |
bc0c38d1 | 2868 | |
1027fcb2 SR |
2869 | mutex_lock(&trace_types_lock); |
2870 | ||
73c5162a SR |
2871 | if (!ring_buffer_expanded) { |
2872 | ret = tracing_resize_ring_buffer(trace_buf_size); | |
2873 | if (ret < 0) | |
59f586db | 2874 | goto out; |
73c5162a SR |
2875 | ret = 0; |
2876 | } | |
2877 | ||
bc0c38d1 SR |
2878 | for (t = trace_types; t; t = t->next) { |
2879 | if (strcmp(t->name, buf) == 0) | |
2880 | break; | |
2881 | } | |
c2931e05 FW |
2882 | if (!t) { |
2883 | ret = -EINVAL; | |
2884 | goto out; | |
2885 | } | |
2886 | if (t == current_trace) | |
bc0c38d1 SR |
2887 | goto out; |
2888 | ||
9f029e83 | 2889 | trace_branch_disable(); |
bc0c38d1 SR |
2890 | if (current_trace && current_trace->reset) |
2891 | current_trace->reset(tr); | |
2892 | ||
577b785f SR |
2893 | destroy_trace_option_files(topts); |
2894 | ||
bc0c38d1 | 2895 | current_trace = t; |
577b785f SR |
2896 | |
2897 | topts = create_trace_option_files(current_trace); | |
2898 | ||
1c80025a | 2899 | if (t->init) { |
b6f11df2 | 2900 | ret = tracer_init(t, tr); |
1c80025a FW |
2901 | if (ret) |
2902 | goto out; | |
2903 | } | |
bc0c38d1 | 2904 | |
9f029e83 | 2905 | trace_branch_enable(tr); |
bc0c38d1 SR |
2906 | out: |
2907 | mutex_unlock(&trace_types_lock); | |
2908 | ||
d9e54076 PZ |
2909 | return ret; |
2910 | } | |
2911 | ||
2912 | static ssize_t | |
2913 | tracing_set_trace_write(struct file *filp, const char __user *ubuf, | |
2914 | size_t cnt, loff_t *ppos) | |
2915 | { | |
ee6c2c1b | 2916 | char buf[MAX_TRACER_SIZE+1]; |
d9e54076 PZ |
2917 | int i; |
2918 | size_t ret; | |
e6e7a65a FW |
2919 | int err; |
2920 | ||
2921 | ret = cnt; | |
d9e54076 | 2922 | |
ee6c2c1b LZ |
2923 | if (cnt > MAX_TRACER_SIZE) |
2924 | cnt = MAX_TRACER_SIZE; | |
d9e54076 PZ |
2925 | |
2926 | if (copy_from_user(&buf, ubuf, cnt)) | |
2927 | return -EFAULT; | |
2928 | ||
2929 | buf[cnt] = 0; | |
2930 | ||
2931 | /* strip ending whitespace. */ | |
2932 | for (i = cnt - 1; i > 0 && isspace(buf[i]); i--) | |
2933 | buf[i] = 0; | |
2934 | ||
e6e7a65a FW |
2935 | err = tracing_set_tracer(buf); |
2936 | if (err) | |
2937 | return err; | |
d9e54076 | 2938 | |
cf8517cf | 2939 | *ppos += ret; |
bc0c38d1 | 2940 | |
c2931e05 | 2941 | return ret; |
bc0c38d1 SR |
2942 | } |
2943 | ||
2944 | static ssize_t | |
2945 | tracing_max_lat_read(struct file *filp, char __user *ubuf, | |
2946 | size_t cnt, loff_t *ppos) | |
2947 | { | |
2948 | unsigned long *ptr = filp->private_data; | |
2949 | char buf[64]; | |
2950 | int r; | |
2951 | ||
cffae437 | 2952 | r = snprintf(buf, sizeof(buf), "%ld\n", |
bc0c38d1 | 2953 | *ptr == (unsigned long)-1 ? -1 : nsecs_to_usecs(*ptr)); |
cffae437 SR |
2954 | if (r > sizeof(buf)) |
2955 | r = sizeof(buf); | |
4bf39a94 | 2956 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, r); |
bc0c38d1 SR |
2957 | } |
2958 | ||
2959 | static ssize_t | |
2960 | tracing_max_lat_write(struct file *filp, const char __user *ubuf, | |
2961 | size_t cnt, loff_t *ppos) | |
2962 | { | |
5e39841c | 2963 | unsigned long *ptr = filp->private_data; |
bc0c38d1 | 2964 | char buf[64]; |
5e39841c | 2965 | unsigned long val; |
c6caeeb1 | 2966 | int ret; |
bc0c38d1 | 2967 | |
cffae437 SR |
2968 | if (cnt >= sizeof(buf)) |
2969 | return -EINVAL; | |
bc0c38d1 SR |
2970 | |
2971 | if (copy_from_user(&buf, ubuf, cnt)) | |
2972 | return -EFAULT; | |
2973 | ||
2974 | buf[cnt] = 0; | |
2975 | ||
c6caeeb1 SR |
2976 | ret = strict_strtoul(buf, 10, &val); |
2977 | if (ret < 0) | |
2978 | return ret; | |
bc0c38d1 SR |
2979 | |
2980 | *ptr = val * 1000; | |
2981 | ||
2982 | return cnt; | |
2983 | } | |
2984 | ||
b3806b43 SR |
2985 | static int tracing_open_pipe(struct inode *inode, struct file *filp) |
2986 | { | |
b04cc6b1 | 2987 | long cpu_file = (long) inode->i_private; |
b3806b43 | 2988 | struct trace_iterator *iter; |
b04cc6b1 | 2989 | int ret = 0; |
b3806b43 SR |
2990 | |
2991 | if (tracing_disabled) | |
2992 | return -ENODEV; | |
2993 | ||
b04cc6b1 FW |
2994 | mutex_lock(&trace_types_lock); |
2995 | ||
b3806b43 SR |
2996 | /* create a buffer to store the information to pass to userspace */ |
2997 | iter = kzalloc(sizeof(*iter), GFP_KERNEL); | |
b04cc6b1 FW |
2998 | if (!iter) { |
2999 | ret = -ENOMEM; | |
3000 | goto out; | |
3001 | } | |
b3806b43 | 3002 | |
d7350c3f FW |
3003 | /* |
3004 | * We make a copy of the current tracer to avoid concurrent | |
3005 | * changes on it while we are reading. | |
3006 | */ | |
3007 | iter->trace = kmalloc(sizeof(*iter->trace), GFP_KERNEL); | |
3008 | if (!iter->trace) { | |
3009 | ret = -ENOMEM; | |
3010 | goto fail; | |
3011 | } | |
3012 | if (current_trace) | |
3013 | *iter->trace = *current_trace; | |
3014 | ||
4462344e | 3015 | if (!alloc_cpumask_var(&iter->started, GFP_KERNEL)) { |
b04cc6b1 | 3016 | ret = -ENOMEM; |
d7350c3f | 3017 | goto fail; |
4462344e RR |
3018 | } |
3019 | ||
a309720c | 3020 | /* trace pipe does not show start of buffer */ |
4462344e | 3021 | cpumask_setall(iter->started); |
a309720c | 3022 | |
112f38a7 SR |
3023 | if (trace_flags & TRACE_ITER_LATENCY_FMT) |
3024 | iter->iter_flags |= TRACE_FILE_LAT_FMT; | |
3025 | ||
b04cc6b1 | 3026 | iter->cpu_file = cpu_file; |
b3806b43 | 3027 | iter->tr = &global_trace; |
d7350c3f | 3028 | mutex_init(&iter->mutex); |
b3806b43 SR |
3029 | filp->private_data = iter; |
3030 | ||
107bad8b SR |
3031 | if (iter->trace->pipe_open) |
3032 | iter->trace->pipe_open(iter); | |
107bad8b | 3033 | |
b04cc6b1 FW |
3034 | out: |
3035 | mutex_unlock(&trace_types_lock); | |
3036 | return ret; | |
d7350c3f FW |
3037 | |
3038 | fail: | |
3039 | kfree(iter->trace); | |
3040 | kfree(iter); | |
3041 | mutex_unlock(&trace_types_lock); | |
3042 | return ret; | |
b3806b43 SR |
3043 | } |
3044 | ||
3045 | static int tracing_release_pipe(struct inode *inode, struct file *file) | |
3046 | { | |
3047 | struct trace_iterator *iter = file->private_data; | |
3048 | ||
b04cc6b1 FW |
3049 | mutex_lock(&trace_types_lock); |
3050 | ||
29bf4a5e | 3051 | if (iter->trace->pipe_close) |
c521efd1 SR |
3052 | iter->trace->pipe_close(iter); |
3053 | ||
b04cc6b1 FW |
3054 | mutex_unlock(&trace_types_lock); |
3055 | ||
4462344e | 3056 | free_cpumask_var(iter->started); |
d7350c3f FW |
3057 | mutex_destroy(&iter->mutex); |
3058 | kfree(iter->trace); | |
b3806b43 | 3059 | kfree(iter); |
b3806b43 SR |
3060 | |
3061 | return 0; | |
3062 | } | |
3063 | ||
2a2cc8f7 SSP |
3064 | static unsigned int |
3065 | tracing_poll_pipe(struct file *filp, poll_table *poll_table) | |
3066 | { | |
3067 | struct trace_iterator *iter = filp->private_data; | |
3068 | ||
3069 | if (trace_flags & TRACE_ITER_BLOCK) { | |
3070 | /* | |
3071 | * Always select as readable when in blocking mode | |
3072 | */ | |
3073 | return POLLIN | POLLRDNORM; | |
afc2abc0 | 3074 | } else { |
2a2cc8f7 SSP |
3075 | if (!trace_empty(iter)) |
3076 | return POLLIN | POLLRDNORM; | |
3077 | poll_wait(filp, &trace_wait, poll_table); | |
3078 | if (!trace_empty(iter)) | |
3079 | return POLLIN | POLLRDNORM; | |
3080 | ||
3081 | return 0; | |
3082 | } | |
3083 | } | |
3084 | ||
6eaaa5d5 FW |
3085 | |
3086 | void default_wait_pipe(struct trace_iterator *iter) | |
3087 | { | |
3088 | DEFINE_WAIT(wait); | |
3089 | ||
3090 | prepare_to_wait(&trace_wait, &wait, TASK_INTERRUPTIBLE); | |
3091 | ||
3092 | if (trace_empty(iter)) | |
3093 | schedule(); | |
3094 | ||
3095 | finish_wait(&trace_wait, &wait); | |
3096 | } | |
3097 | ||
3098 | /* | |
3099 | * This is a make-shift waitqueue. | |
3100 | * A tracer might use this callback on some rare cases: | |
3101 | * | |
3102 | * 1) the current tracer might hold the runqueue lock when it wakes up | |
3103 | * a reader, hence a deadlock (sched, function, and function graph tracers) | |
3104 | * 2) the function tracers, trace all functions, we don't want | |
3105 | * the overhead of calling wake_up and friends | |
3106 | * (and tracing them too) | |
3107 | * | |
3108 | * Anyway, this is really very primitive wakeup. | |
3109 | */ | |
3110 | void poll_wait_pipe(struct trace_iterator *iter) | |
3111 | { | |
3112 | set_current_state(TASK_INTERRUPTIBLE); | |
3113 | /* sleep for 100 msecs, and try again. */ | |
3114 | schedule_timeout(HZ / 10); | |
3115 | } | |
3116 | ||
ff98781b EGM |
3117 | /* Must be called with trace_types_lock mutex held. */ |
3118 | static int tracing_wait_pipe(struct file *filp) | |
b3806b43 SR |
3119 | { |
3120 | struct trace_iterator *iter = filp->private_data; | |
b3806b43 | 3121 | |
b3806b43 | 3122 | while (trace_empty(iter)) { |
2dc8f095 | 3123 | |
107bad8b | 3124 | if ((filp->f_flags & O_NONBLOCK)) { |
ff98781b | 3125 | return -EAGAIN; |
107bad8b | 3126 | } |
2dc8f095 | 3127 | |
d7350c3f | 3128 | mutex_unlock(&iter->mutex); |
107bad8b | 3129 | |
6eaaa5d5 | 3130 | iter->trace->wait_pipe(iter); |
b3806b43 | 3131 | |
d7350c3f | 3132 | mutex_lock(&iter->mutex); |
107bad8b | 3133 | |
6eaaa5d5 | 3134 | if (signal_pending(current)) |
ff98781b | 3135 | return -EINTR; |
b3806b43 SR |
3136 | |
3137 | /* | |
3138 | * We block until we read something and tracing is disabled. | |
3139 | * We still block if tracing is disabled, but we have never | |
3140 | * read anything. This allows a user to cat this file, and | |
3141 | * then enable tracing. But after we have read something, | |
3142 | * we give an EOF when tracing is again disabled. | |
3143 | * | |
3144 | * iter->pos will be 0 if we haven't read anything. | |
3145 | */ | |
3146 | if (!tracer_enabled && iter->pos) | |
3147 | break; | |
b3806b43 SR |
3148 | } |
3149 | ||
ff98781b EGM |
3150 | return 1; |
3151 | } | |
3152 | ||
3153 | /* | |
3154 | * Consumer reader. | |
3155 | */ | |
3156 | static ssize_t | |
3157 | tracing_read_pipe(struct file *filp, char __user *ubuf, | |
3158 | size_t cnt, loff_t *ppos) | |
3159 | { | |
3160 | struct trace_iterator *iter = filp->private_data; | |
d7350c3f | 3161 | static struct tracer *old_tracer; |
ff98781b EGM |
3162 | ssize_t sret; |
3163 | ||
3164 | /* return any leftover data */ | |
3165 | sret = trace_seq_to_user(&iter->seq, ubuf, cnt); | |
3166 | if (sret != -EBUSY) | |
3167 | return sret; | |
3168 | ||
f9520750 | 3169 | trace_seq_init(&iter->seq); |
ff98781b | 3170 | |
d7350c3f | 3171 | /* copy the tracer to avoid using a global lock all around */ |
ff98781b | 3172 | mutex_lock(&trace_types_lock); |
d7350c3f FW |
3173 | if (unlikely(old_tracer != current_trace && current_trace)) { |
3174 | old_tracer = current_trace; | |
3175 | *iter->trace = *current_trace; | |
3176 | } | |
3177 | mutex_unlock(&trace_types_lock); | |
3178 | ||
3179 | /* | |
3180 | * Avoid more than one consumer on a single file descriptor | |
3181 | * This is just a matter of traces coherency, the ring buffer itself | |
3182 | * is protected. | |
3183 | */ | |
3184 | mutex_lock(&iter->mutex); | |
ff98781b EGM |
3185 | if (iter->trace->read) { |
3186 | sret = iter->trace->read(iter, filp, ubuf, cnt, ppos); | |
3187 | if (sret) | |
3188 | goto out; | |
3189 | } | |
3190 | ||
3191 | waitagain: | |
3192 | sret = tracing_wait_pipe(filp); | |
3193 | if (sret <= 0) | |
3194 | goto out; | |
3195 | ||
b3806b43 | 3196 | /* stop when tracing is finished */ |
ff98781b EGM |
3197 | if (trace_empty(iter)) { |
3198 | sret = 0; | |
107bad8b | 3199 | goto out; |
ff98781b | 3200 | } |
b3806b43 SR |
3201 | |
3202 | if (cnt >= PAGE_SIZE) | |
3203 | cnt = PAGE_SIZE - 1; | |
3204 | ||
53d0aa77 | 3205 | /* reset all but tr, trace, and overruns */ |
53d0aa77 SR |
3206 | memset(&iter->seq, 0, |
3207 | sizeof(struct trace_iterator) - | |
3208 | offsetof(struct trace_iterator, seq)); | |
4823ed7e | 3209 | iter->pos = -1; |
b3806b43 | 3210 | |
4f535968 | 3211 | trace_event_read_lock(); |
7e53bd42 | 3212 | trace_access_lock(iter->cpu_file); |
088b1e42 | 3213 | while (find_next_entry_inc(iter) != NULL) { |
2c4f035f | 3214 | enum print_line_t ret; |
088b1e42 SR |
3215 | int len = iter->seq.len; |
3216 | ||
f9896bf3 | 3217 | ret = print_trace_line(iter); |
2c4f035f | 3218 | if (ret == TRACE_TYPE_PARTIAL_LINE) { |
088b1e42 SR |
3219 | /* don't print partial lines */ |
3220 | iter->seq.len = len; | |
b3806b43 | 3221 | break; |
088b1e42 | 3222 | } |
b91facc3 FW |
3223 | if (ret != TRACE_TYPE_NO_CONSUME) |
3224 | trace_consume(iter); | |
b3806b43 SR |
3225 | |
3226 | if (iter->seq.len >= cnt) | |
3227 | break; | |
b3806b43 | 3228 | } |
7e53bd42 | 3229 | trace_access_unlock(iter->cpu_file); |
4f535968 | 3230 | trace_event_read_unlock(); |
b3806b43 | 3231 | |
b3806b43 | 3232 | /* Now copy what we have to the user */ |
6c6c2796 PP |
3233 | sret = trace_seq_to_user(&iter->seq, ubuf, cnt); |
3234 | if (iter->seq.readpos >= iter->seq.len) | |
f9520750 | 3235 | trace_seq_init(&iter->seq); |
9ff4b974 PP |
3236 | |
3237 | /* | |
3238 | * If there was nothing to send to user, inspite of consuming trace | |
3239 | * entries, go back to wait for more entries. | |
3240 | */ | |
6c6c2796 | 3241 | if (sret == -EBUSY) |
9ff4b974 | 3242 | goto waitagain; |
b3806b43 | 3243 | |
107bad8b | 3244 | out: |
d7350c3f | 3245 | mutex_unlock(&iter->mutex); |
107bad8b | 3246 | |
6c6c2796 | 3247 | return sret; |
b3806b43 SR |
3248 | } |
3249 | ||
3c56819b EGM |
3250 | static void tracing_pipe_buf_release(struct pipe_inode_info *pipe, |
3251 | struct pipe_buffer *buf) | |
3252 | { | |
3253 | __free_page(buf->page); | |
3254 | } | |
3255 | ||
3256 | static void tracing_spd_release_pipe(struct splice_pipe_desc *spd, | |
3257 | unsigned int idx) | |
3258 | { | |
3259 | __free_page(spd->pages[idx]); | |
3260 | } | |
3261 | ||
28dfef8f | 3262 | static const struct pipe_buf_operations tracing_pipe_buf_ops = { |
34cd4998 SR |
3263 | .can_merge = 0, |
3264 | .map = generic_pipe_buf_map, | |
3265 | .unmap = generic_pipe_buf_unmap, | |
3266 | .confirm = generic_pipe_buf_confirm, | |
3267 | .release = tracing_pipe_buf_release, | |
3268 | .steal = generic_pipe_buf_steal, | |
3269 | .get = generic_pipe_buf_get, | |
3c56819b EGM |
3270 | }; |
3271 | ||
34cd4998 | 3272 | static size_t |
fa7c7f6e | 3273 | tracing_fill_pipe_page(size_t rem, struct trace_iterator *iter) |
34cd4998 SR |
3274 | { |
3275 | size_t count; | |
3276 | int ret; | |
3277 | ||
3278 | /* Seq buffer is page-sized, exactly what we need. */ | |
3279 | for (;;) { | |
3280 | count = iter->seq.len; | |
3281 | ret = print_trace_line(iter); | |
3282 | count = iter->seq.len - count; | |
3283 | if (rem < count) { | |
3284 | rem = 0; | |
3285 | iter->seq.len -= count; | |
3286 | break; | |
3287 | } | |
3288 | if (ret == TRACE_TYPE_PARTIAL_LINE) { | |
3289 | iter->seq.len -= count; | |
3290 | break; | |
3291 | } | |
3292 | ||
74e7ff8c LJ |
3293 | if (ret != TRACE_TYPE_NO_CONSUME) |
3294 | trace_consume(iter); | |
34cd4998 SR |
3295 | rem -= count; |
3296 | if (!find_next_entry_inc(iter)) { | |
3297 | rem = 0; | |
3298 | iter->ent = NULL; | |
3299 | break; | |
3300 | } | |
3301 | } | |
3302 | ||
3303 | return rem; | |
3304 | } | |
3305 | ||
3c56819b EGM |
3306 | static ssize_t tracing_splice_read_pipe(struct file *filp, |
3307 | loff_t *ppos, | |
3308 | struct pipe_inode_info *pipe, | |
3309 | size_t len, | |
3310 | unsigned int flags) | |
3311 | { | |
3312 | struct page *pages[PIPE_BUFFERS]; | |
3313 | struct partial_page partial[PIPE_BUFFERS]; | |
3314 | struct trace_iterator *iter = filp->private_data; | |
3315 | struct splice_pipe_desc spd = { | |
34cd4998 SR |
3316 | .pages = pages, |
3317 | .partial = partial, | |
3318 | .nr_pages = 0, /* This gets updated below. */ | |
3319 | .flags = flags, | |
3320 | .ops = &tracing_pipe_buf_ops, | |
3321 | .spd_release = tracing_spd_release_pipe, | |
3c56819b | 3322 | }; |
d7350c3f | 3323 | static struct tracer *old_tracer; |
3c56819b | 3324 | ssize_t ret; |
34cd4998 | 3325 | size_t rem; |
3c56819b EGM |
3326 | unsigned int i; |
3327 | ||
d7350c3f | 3328 | /* copy the tracer to avoid using a global lock all around */ |
3c56819b | 3329 | mutex_lock(&trace_types_lock); |
d7350c3f FW |
3330 | if (unlikely(old_tracer != current_trace && current_trace)) { |
3331 | old_tracer = current_trace; | |
3332 | *iter->trace = *current_trace; | |
3333 | } | |
3334 | mutex_unlock(&trace_types_lock); | |
3335 | ||
3336 | mutex_lock(&iter->mutex); | |
3c56819b EGM |
3337 | |
3338 | if (iter->trace->splice_read) { | |
3339 | ret = iter->trace->splice_read(iter, filp, | |
3340 | ppos, pipe, len, flags); | |
3341 | if (ret) | |
34cd4998 | 3342 | goto out_err; |
3c56819b EGM |
3343 | } |
3344 | ||
3345 | ret = tracing_wait_pipe(filp); | |
3346 | if (ret <= 0) | |
34cd4998 | 3347 | goto out_err; |
3c56819b EGM |
3348 | |
3349 | if (!iter->ent && !find_next_entry_inc(iter)) { | |
3350 | ret = -EFAULT; | |
34cd4998 | 3351 | goto out_err; |
3c56819b EGM |
3352 | } |
3353 | ||
4f535968 | 3354 | trace_event_read_lock(); |
7e53bd42 | 3355 | trace_access_lock(iter->cpu_file); |
4f535968 | 3356 | |
3c56819b EGM |
3357 | /* Fill as many pages as possible. */ |
3358 | for (i = 0, rem = len; i < PIPE_BUFFERS && rem; i++) { | |
3359 | pages[i] = alloc_page(GFP_KERNEL); | |
34cd4998 SR |
3360 | if (!pages[i]) |
3361 | break; | |
3c56819b | 3362 | |
fa7c7f6e | 3363 | rem = tracing_fill_pipe_page(rem, iter); |
3c56819b EGM |
3364 | |
3365 | /* Copy the data into the page, so we can start over. */ | |
3366 | ret = trace_seq_to_buffer(&iter->seq, | |
3367 | page_address(pages[i]), | |
3368 | iter->seq.len); | |
3369 | if (ret < 0) { | |
3370 | __free_page(pages[i]); | |
3371 | break; | |
3372 | } | |
3373 | partial[i].offset = 0; | |
3374 | partial[i].len = iter->seq.len; | |
3375 | ||
f9520750 | 3376 | trace_seq_init(&iter->seq); |
3c56819b EGM |
3377 | } |
3378 | ||
7e53bd42 | 3379 | trace_access_unlock(iter->cpu_file); |
4f535968 | 3380 | trace_event_read_unlock(); |
d7350c3f | 3381 | mutex_unlock(&iter->mutex); |
3c56819b EGM |
3382 | |
3383 | spd.nr_pages = i; | |
3384 | ||
3385 | return splice_to_pipe(pipe, &spd); | |
3386 | ||
34cd4998 | 3387 | out_err: |
d7350c3f | 3388 | mutex_unlock(&iter->mutex); |
3c56819b EGM |
3389 | |
3390 | return ret; | |
3391 | } | |
3392 | ||
a98a3c3f SR |
3393 | static ssize_t |
3394 | tracing_entries_read(struct file *filp, char __user *ubuf, | |
3395 | size_t cnt, loff_t *ppos) | |
3396 | { | |
3397 | struct trace_array *tr = filp->private_data; | |
db526ca3 | 3398 | char buf[96]; |
a98a3c3f SR |
3399 | int r; |
3400 | ||
db526ca3 SR |
3401 | mutex_lock(&trace_types_lock); |
3402 | if (!ring_buffer_expanded) | |
3403 | r = sprintf(buf, "%lu (expanded: %lu)\n", | |
3404 | tr->entries >> 10, | |
3405 | trace_buf_size >> 10); | |
3406 | else | |
3407 | r = sprintf(buf, "%lu\n", tr->entries >> 10); | |
3408 | mutex_unlock(&trace_types_lock); | |
3409 | ||
a98a3c3f SR |
3410 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, r); |
3411 | } | |
3412 | ||
3413 | static ssize_t | |
3414 | tracing_entries_write(struct file *filp, const char __user *ubuf, | |
3415 | size_t cnt, loff_t *ppos) | |
3416 | { | |
3417 | unsigned long val; | |
3418 | char buf[64]; | |
bf5e6519 | 3419 | int ret, cpu; |
a98a3c3f | 3420 | |
cffae437 SR |
3421 | if (cnt >= sizeof(buf)) |
3422 | return -EINVAL; | |
a98a3c3f SR |
3423 | |
3424 | if (copy_from_user(&buf, ubuf, cnt)) | |
3425 | return -EFAULT; | |
3426 | ||
3427 | buf[cnt] = 0; | |
3428 | ||
c6caeeb1 SR |
3429 | ret = strict_strtoul(buf, 10, &val); |
3430 | if (ret < 0) | |
3431 | return ret; | |
a98a3c3f SR |
3432 | |
3433 | /* must have at least 1 entry */ | |
3434 | if (!val) | |
3435 | return -EINVAL; | |
3436 | ||
3437 | mutex_lock(&trace_types_lock); | |
3438 | ||
c76f0694 | 3439 | tracing_stop(); |
a98a3c3f | 3440 | |
bf5e6519 SR |
3441 | /* disable all cpu buffers */ |
3442 | for_each_tracing_cpu(cpu) { | |
3443 | if (global_trace.data[cpu]) | |
3444 | atomic_inc(&global_trace.data[cpu]->disabled); | |
3445 | if (max_tr.data[cpu]) | |
3446 | atomic_inc(&max_tr.data[cpu]->disabled); | |
3447 | } | |
3448 | ||
1696b2b0 SR |
3449 | /* value is in KB */ |
3450 | val <<= 10; | |
3451 | ||
3928a8a2 | 3452 | if (val != global_trace.entries) { |
73c5162a | 3453 | ret = tracing_resize_ring_buffer(val); |
3928a8a2 SR |
3454 | if (ret < 0) { |
3455 | cnt = ret; | |
3eefae99 SR |
3456 | goto out; |
3457 | } | |
a98a3c3f SR |
3458 | } |
3459 | ||
cf8517cf | 3460 | *ppos += cnt; |
a98a3c3f | 3461 | |
19384c03 SR |
3462 | /* If check pages failed, return ENOMEM */ |
3463 | if (tracing_disabled) | |
3464 | cnt = -ENOMEM; | |
a98a3c3f | 3465 | out: |
bf5e6519 SR |
3466 | for_each_tracing_cpu(cpu) { |
3467 | if (global_trace.data[cpu]) | |
3468 | atomic_dec(&global_trace.data[cpu]->disabled); | |
3469 | if (max_tr.data[cpu]) | |
3470 | atomic_dec(&max_tr.data[cpu]->disabled); | |
3471 | } | |
3472 | ||
c76f0694 | 3473 | tracing_start(); |
a98a3c3f SR |
3474 | max_tr.entries = global_trace.entries; |
3475 | mutex_unlock(&trace_types_lock); | |
3476 | ||
3477 | return cnt; | |
3478 | } | |
3479 | ||
f2942487 CE |
3480 | static int mark_printk(const char *fmt, ...) |
3481 | { | |
3482 | int ret; | |
3483 | va_list args; | |
3484 | va_start(args, fmt); | |
3485 | ret = trace_vprintk(0, fmt, args); | |
3486 | va_end(args); | |
3487 | return ret; | |
3488 | } | |
3489 | ||
5bf9a1ee PP |
3490 | static ssize_t |
3491 | tracing_mark_write(struct file *filp, const char __user *ubuf, | |
3492 | size_t cnt, loff_t *fpos) | |
3493 | { | |
3494 | char *buf; | |
5bf9a1ee | 3495 | |
c76f0694 | 3496 | if (tracing_disabled) |
5bf9a1ee PP |
3497 | return -EINVAL; |
3498 | ||
3499 | if (cnt > TRACE_BUF_SIZE) | |
3500 | cnt = TRACE_BUF_SIZE; | |
3501 | ||
c13d2f7c | 3502 | buf = kmalloc(cnt + 2, GFP_KERNEL); |
5bf9a1ee PP |
3503 | if (buf == NULL) |
3504 | return -ENOMEM; | |
3505 | ||
3506 | if (copy_from_user(buf, ubuf, cnt)) { | |
3507 | kfree(buf); | |
3508 | return -EFAULT; | |
3509 | } | |
c13d2f7c CE |
3510 | if (buf[cnt-1] != '\n') { |
3511 | buf[cnt] = '\n'; | |
3512 | buf[cnt+1] = '\0'; | |
3513 | } else | |
3514 | buf[cnt] = '\0'; | |
5bf9a1ee | 3515 | |
f2942487 | 3516 | cnt = mark_printk("%s", buf); |
5bf9a1ee PP |
3517 | kfree(buf); |
3518 | *fpos += cnt; | |
3519 | ||
3520 | return cnt; | |
3521 | } | |
3522 | ||
13f16d20 | 3523 | static int tracing_clock_show(struct seq_file *m, void *v) |
5079f326 | 3524 | { |
5079f326 Z |
3525 | int i; |
3526 | ||
3527 | for (i = 0; i < ARRAY_SIZE(trace_clocks); i++) | |
13f16d20 | 3528 | seq_printf(m, |
5079f326 Z |
3529 | "%s%s%s%s", i ? " " : "", |
3530 | i == trace_clock_id ? "[" : "", trace_clocks[i].name, | |
3531 | i == trace_clock_id ? "]" : ""); | |
13f16d20 | 3532 | seq_putc(m, '\n'); |
5079f326 | 3533 | |
13f16d20 | 3534 | return 0; |
5079f326 Z |
3535 | } |
3536 | ||
3537 | static ssize_t tracing_clock_write(struct file *filp, const char __user *ubuf, | |
3538 | size_t cnt, loff_t *fpos) | |
3539 | { | |
3540 | char buf[64]; | |
3541 | const char *clockstr; | |
3542 | int i; | |
3543 | ||
3544 | if (cnt >= sizeof(buf)) | |
3545 | return -EINVAL; | |
3546 | ||
3547 | if (copy_from_user(&buf, ubuf, cnt)) | |
3548 | return -EFAULT; | |
3549 | ||
3550 | buf[cnt] = 0; | |
3551 | ||
3552 | clockstr = strstrip(buf); | |
3553 | ||
3554 | for (i = 0; i < ARRAY_SIZE(trace_clocks); i++) { | |
3555 | if (strcmp(trace_clocks[i].name, clockstr) == 0) | |
3556 | break; | |
3557 | } | |
3558 | if (i == ARRAY_SIZE(trace_clocks)) | |
3559 | return -EINVAL; | |
3560 | ||
3561 | trace_clock_id = i; | |
3562 | ||
3563 | mutex_lock(&trace_types_lock); | |
3564 | ||
3565 | ring_buffer_set_clock(global_trace.buffer, trace_clocks[i].func); | |
3566 | if (max_tr.buffer) | |
3567 | ring_buffer_set_clock(max_tr.buffer, trace_clocks[i].func); | |
3568 | ||
3569 | mutex_unlock(&trace_types_lock); | |
3570 | ||
3571 | *fpos += cnt; | |
3572 | ||
3573 | return cnt; | |
3574 | } | |
3575 | ||
13f16d20 LZ |
3576 | static int tracing_clock_open(struct inode *inode, struct file *file) |
3577 | { | |
3578 | if (tracing_disabled) | |
3579 | return -ENODEV; | |
3580 | return single_open(file, tracing_clock_show, NULL); | |
3581 | } | |
3582 | ||
5e2336a0 | 3583 | static const struct file_operations tracing_max_lat_fops = { |
4bf39a94 IM |
3584 | .open = tracing_open_generic, |
3585 | .read = tracing_max_lat_read, | |
3586 | .write = tracing_max_lat_write, | |
bc0c38d1 SR |
3587 | }; |
3588 | ||
5e2336a0 | 3589 | static const struct file_operations tracing_ctrl_fops = { |
4bf39a94 IM |
3590 | .open = tracing_open_generic, |
3591 | .read = tracing_ctrl_read, | |
3592 | .write = tracing_ctrl_write, | |
bc0c38d1 SR |
3593 | }; |
3594 | ||
5e2336a0 | 3595 | static const struct file_operations set_tracer_fops = { |
4bf39a94 IM |
3596 | .open = tracing_open_generic, |
3597 | .read = tracing_set_trace_read, | |
3598 | .write = tracing_set_trace_write, | |
bc0c38d1 SR |
3599 | }; |
3600 | ||
5e2336a0 | 3601 | static const struct file_operations tracing_pipe_fops = { |
4bf39a94 | 3602 | .open = tracing_open_pipe, |
2a2cc8f7 | 3603 | .poll = tracing_poll_pipe, |
4bf39a94 | 3604 | .read = tracing_read_pipe, |
3c56819b | 3605 | .splice_read = tracing_splice_read_pipe, |
4bf39a94 | 3606 | .release = tracing_release_pipe, |
b3806b43 SR |
3607 | }; |
3608 | ||
5e2336a0 | 3609 | static const struct file_operations tracing_entries_fops = { |
a98a3c3f SR |
3610 | .open = tracing_open_generic, |
3611 | .read = tracing_entries_read, | |
3612 | .write = tracing_entries_write, | |
3613 | }; | |
3614 | ||
5e2336a0 | 3615 | static const struct file_operations tracing_mark_fops = { |
43a15386 | 3616 | .open = tracing_open_generic, |
5bf9a1ee PP |
3617 | .write = tracing_mark_write, |
3618 | }; | |
3619 | ||
5079f326 | 3620 | static const struct file_operations trace_clock_fops = { |
13f16d20 LZ |
3621 | .open = tracing_clock_open, |
3622 | .read = seq_read, | |
3623 | .llseek = seq_lseek, | |
3624 | .release = single_release, | |
5079f326 Z |
3625 | .write = tracing_clock_write, |
3626 | }; | |
3627 | ||
2cadf913 SR |
3628 | struct ftrace_buffer_info { |
3629 | struct trace_array *tr; | |
3630 | void *spare; | |
3631 | int cpu; | |
3632 | unsigned int read; | |
3633 | }; | |
3634 | ||
3635 | static int tracing_buffers_open(struct inode *inode, struct file *filp) | |
3636 | { | |
3637 | int cpu = (int)(long)inode->i_private; | |
3638 | struct ftrace_buffer_info *info; | |
3639 | ||
3640 | if (tracing_disabled) | |
3641 | return -ENODEV; | |
3642 | ||
3643 | info = kzalloc(sizeof(*info), GFP_KERNEL); | |
3644 | if (!info) | |
3645 | return -ENOMEM; | |
3646 | ||
3647 | info->tr = &global_trace; | |
3648 | info->cpu = cpu; | |
ddd538f3 | 3649 | info->spare = NULL; |
2cadf913 SR |
3650 | /* Force reading ring buffer for first read */ |
3651 | info->read = (unsigned int)-1; | |
2cadf913 SR |
3652 | |
3653 | filp->private_data = info; | |
3654 | ||
d1e7e02f | 3655 | return nonseekable_open(inode, filp); |
2cadf913 SR |
3656 | } |
3657 | ||
3658 | static ssize_t | |
3659 | tracing_buffers_read(struct file *filp, char __user *ubuf, | |
3660 | size_t count, loff_t *ppos) | |
3661 | { | |
3662 | struct ftrace_buffer_info *info = filp->private_data; | |
3663 | unsigned int pos; | |
3664 | ssize_t ret; | |
3665 | size_t size; | |
3666 | ||
2dc5d12b SR |
3667 | if (!count) |
3668 | return 0; | |
3669 | ||
ddd538f3 LJ |
3670 | if (!info->spare) |
3671 | info->spare = ring_buffer_alloc_read_page(info->tr->buffer); | |
3672 | if (!info->spare) | |
3673 | return -ENOMEM; | |
3674 | ||
2cadf913 SR |
3675 | /* Do we have previous read data to read? */ |
3676 | if (info->read < PAGE_SIZE) | |
3677 | goto read; | |
3678 | ||
3679 | info->read = 0; | |
3680 | ||
7e53bd42 | 3681 | trace_access_lock(info->cpu); |
2cadf913 SR |
3682 | ret = ring_buffer_read_page(info->tr->buffer, |
3683 | &info->spare, | |
3684 | count, | |
3685 | info->cpu, 0); | |
7e53bd42 | 3686 | trace_access_unlock(info->cpu); |
2cadf913 SR |
3687 | if (ret < 0) |
3688 | return 0; | |
3689 | ||
3690 | pos = ring_buffer_page_len(info->spare); | |
3691 | ||
3692 | if (pos < PAGE_SIZE) | |
3693 | memset(info->spare + pos, 0, PAGE_SIZE - pos); | |
3694 | ||
3695 | read: | |
3696 | size = PAGE_SIZE - info->read; | |
3697 | if (size > count) | |
3698 | size = count; | |
3699 | ||
3700 | ret = copy_to_user(ubuf, info->spare + info->read, size); | |
2dc5d12b | 3701 | if (ret == size) |
2cadf913 | 3702 | return -EFAULT; |
2dc5d12b SR |
3703 | size -= ret; |
3704 | ||
2cadf913 SR |
3705 | *ppos += size; |
3706 | info->read += size; | |
3707 | ||
3708 | return size; | |
3709 | } | |
3710 | ||
3711 | static int tracing_buffers_release(struct inode *inode, struct file *file) | |
3712 | { | |
3713 | struct ftrace_buffer_info *info = file->private_data; | |
3714 | ||
ddd538f3 LJ |
3715 | if (info->spare) |
3716 | ring_buffer_free_read_page(info->tr->buffer, info->spare); | |
2cadf913 SR |
3717 | kfree(info); |
3718 | ||
3719 | return 0; | |
3720 | } | |
3721 | ||
3722 | struct buffer_ref { | |
3723 | struct ring_buffer *buffer; | |
3724 | void *page; | |
3725 | int ref; | |
3726 | }; | |
3727 | ||
3728 | static void buffer_pipe_buf_release(struct pipe_inode_info *pipe, | |
3729 | struct pipe_buffer *buf) | |
3730 | { | |
3731 | struct buffer_ref *ref = (struct buffer_ref *)buf->private; | |
3732 | ||
3733 | if (--ref->ref) | |
3734 | return; | |
3735 | ||
3736 | ring_buffer_free_read_page(ref->buffer, ref->page); | |
3737 | kfree(ref); | |
3738 | buf->private = 0; | |
3739 | } | |
3740 | ||
3741 | static int buffer_pipe_buf_steal(struct pipe_inode_info *pipe, | |
3742 | struct pipe_buffer *buf) | |
3743 | { | |
3744 | return 1; | |
3745 | } | |
3746 | ||
3747 | static void buffer_pipe_buf_get(struct pipe_inode_info *pipe, | |
3748 | struct pipe_buffer *buf) | |
3749 | { | |
3750 | struct buffer_ref *ref = (struct buffer_ref *)buf->private; | |
3751 | ||
3752 | ref->ref++; | |
3753 | } | |
3754 | ||
3755 | /* Pipe buffer operations for a buffer. */ | |
28dfef8f | 3756 | static const struct pipe_buf_operations buffer_pipe_buf_ops = { |
2cadf913 SR |
3757 | .can_merge = 0, |
3758 | .map = generic_pipe_buf_map, | |
3759 | .unmap = generic_pipe_buf_unmap, | |
3760 | .confirm = generic_pipe_buf_confirm, | |
3761 | .release = buffer_pipe_buf_release, | |
3762 | .steal = buffer_pipe_buf_steal, | |
3763 | .get = buffer_pipe_buf_get, | |
3764 | }; | |
3765 | ||
3766 | /* | |
3767 | * Callback from splice_to_pipe(), if we need to release some pages | |
3768 | * at the end of the spd in case we error'ed out in filling the pipe. | |
3769 | */ | |
3770 | static void buffer_spd_release(struct splice_pipe_desc *spd, unsigned int i) | |
3771 | { | |
3772 | struct buffer_ref *ref = | |
3773 | (struct buffer_ref *)spd->partial[i].private; | |
3774 | ||
3775 | if (--ref->ref) | |
3776 | return; | |
3777 | ||
3778 | ring_buffer_free_read_page(ref->buffer, ref->page); | |
3779 | kfree(ref); | |
3780 | spd->partial[i].private = 0; | |
3781 | } | |
3782 | ||
3783 | static ssize_t | |
3784 | tracing_buffers_splice_read(struct file *file, loff_t *ppos, | |
3785 | struct pipe_inode_info *pipe, size_t len, | |
3786 | unsigned int flags) | |
3787 | { | |
3788 | struct ftrace_buffer_info *info = file->private_data; | |
3789 | struct partial_page partial[PIPE_BUFFERS]; | |
3790 | struct page *pages[PIPE_BUFFERS]; | |
3791 | struct splice_pipe_desc spd = { | |
3792 | .pages = pages, | |
3793 | .partial = partial, | |
3794 | .flags = flags, | |
3795 | .ops = &buffer_pipe_buf_ops, | |
3796 | .spd_release = buffer_spd_release, | |
3797 | }; | |
3798 | struct buffer_ref *ref; | |
93459c6c | 3799 | int entries, size, i; |
2cadf913 SR |
3800 | size_t ret; |
3801 | ||
93cfb3c9 LJ |
3802 | if (*ppos & (PAGE_SIZE - 1)) { |
3803 | WARN_ONCE(1, "Ftrace: previous read must page-align\n"); | |
3804 | return -EINVAL; | |
3805 | } | |
3806 | ||
3807 | if (len & (PAGE_SIZE - 1)) { | |
3808 | WARN_ONCE(1, "Ftrace: splice_read should page-align\n"); | |
3809 | if (len < PAGE_SIZE) | |
3810 | return -EINVAL; | |
3811 | len &= PAGE_MASK; | |
3812 | } | |
3813 | ||
7e53bd42 | 3814 | trace_access_lock(info->cpu); |
93459c6c SR |
3815 | entries = ring_buffer_entries_cpu(info->tr->buffer, info->cpu); |
3816 | ||
3817 | for (i = 0; i < PIPE_BUFFERS && len && entries; i++, len -= PAGE_SIZE) { | |
2cadf913 SR |
3818 | struct page *page; |
3819 | int r; | |
3820 | ||
3821 | ref = kzalloc(sizeof(*ref), GFP_KERNEL); | |
3822 | if (!ref) | |
3823 | break; | |
3824 | ||
7267fa68 | 3825 | ref->ref = 1; |
2cadf913 SR |
3826 | ref->buffer = info->tr->buffer; |
3827 | ref->page = ring_buffer_alloc_read_page(ref->buffer); | |
3828 | if (!ref->page) { | |
3829 | kfree(ref); | |
3830 | break; | |
3831 | } | |
3832 | ||
3833 | r = ring_buffer_read_page(ref->buffer, &ref->page, | |
f2957f1f | 3834 | len, info->cpu, 1); |
2cadf913 SR |
3835 | if (r < 0) { |
3836 | ring_buffer_free_read_page(ref->buffer, | |
3837 | ref->page); | |
3838 | kfree(ref); | |
3839 | break; | |
3840 | } | |
3841 | ||
3842 | /* | |
3843 | * zero out any left over data, this is going to | |
3844 | * user land. | |
3845 | */ | |
3846 | size = ring_buffer_page_len(ref->page); | |
3847 | if (size < PAGE_SIZE) | |
3848 | memset(ref->page + size, 0, PAGE_SIZE - size); | |
3849 | ||
3850 | page = virt_to_page(ref->page); | |
3851 | ||
3852 | spd.pages[i] = page; | |
3853 | spd.partial[i].len = PAGE_SIZE; | |
3854 | spd.partial[i].offset = 0; | |
3855 | spd.partial[i].private = (unsigned long)ref; | |
3856 | spd.nr_pages++; | |
93cfb3c9 | 3857 | *ppos += PAGE_SIZE; |
93459c6c SR |
3858 | |
3859 | entries = ring_buffer_entries_cpu(info->tr->buffer, info->cpu); | |
2cadf913 SR |
3860 | } |
3861 | ||
7e53bd42 | 3862 | trace_access_unlock(info->cpu); |
2cadf913 SR |
3863 | spd.nr_pages = i; |
3864 | ||
3865 | /* did we read anything? */ | |
3866 | if (!spd.nr_pages) { | |
3867 | if (flags & SPLICE_F_NONBLOCK) | |
3868 | ret = -EAGAIN; | |
3869 | else | |
3870 | ret = 0; | |
3871 | /* TODO: block */ | |
3872 | return ret; | |
3873 | } | |
3874 | ||
3875 | ret = splice_to_pipe(pipe, &spd); | |
3876 | ||
3877 | return ret; | |
3878 | } | |
3879 | ||
3880 | static const struct file_operations tracing_buffers_fops = { | |
3881 | .open = tracing_buffers_open, | |
3882 | .read = tracing_buffers_read, | |
3883 | .release = tracing_buffers_release, | |
3884 | .splice_read = tracing_buffers_splice_read, | |
3885 | .llseek = no_llseek, | |
3886 | }; | |
3887 | ||
c8d77183 SR |
3888 | static ssize_t |
3889 | tracing_stats_read(struct file *filp, char __user *ubuf, | |
3890 | size_t count, loff_t *ppos) | |
3891 | { | |
3892 | unsigned long cpu = (unsigned long)filp->private_data; | |
3893 | struct trace_array *tr = &global_trace; | |
3894 | struct trace_seq *s; | |
3895 | unsigned long cnt; | |
3896 | ||
e4f2d10f | 3897 | s = kmalloc(sizeof(*s), GFP_KERNEL); |
c8d77183 | 3898 | if (!s) |
a646365c | 3899 | return -ENOMEM; |
c8d77183 SR |
3900 | |
3901 | trace_seq_init(s); | |
3902 | ||
3903 | cnt = ring_buffer_entries_cpu(tr->buffer, cpu); | |
3904 | trace_seq_printf(s, "entries: %ld\n", cnt); | |
3905 | ||
3906 | cnt = ring_buffer_overrun_cpu(tr->buffer, cpu); | |
3907 | trace_seq_printf(s, "overrun: %ld\n", cnt); | |
3908 | ||
3909 | cnt = ring_buffer_commit_overrun_cpu(tr->buffer, cpu); | |
3910 | trace_seq_printf(s, "commit overrun: %ld\n", cnt); | |
3911 | ||
c8d77183 SR |
3912 | count = simple_read_from_buffer(ubuf, count, ppos, s->buffer, s->len); |
3913 | ||
3914 | kfree(s); | |
3915 | ||
3916 | return count; | |
3917 | } | |
3918 | ||
3919 | static const struct file_operations tracing_stats_fops = { | |
3920 | .open = tracing_open_generic, | |
3921 | .read = tracing_stats_read, | |
3922 | }; | |
3923 | ||
bc0c38d1 SR |
3924 | #ifdef CONFIG_DYNAMIC_FTRACE |
3925 | ||
b807c3d0 SR |
3926 | int __weak ftrace_arch_read_dyn_info(char *buf, int size) |
3927 | { | |
3928 | return 0; | |
3929 | } | |
3930 | ||
bc0c38d1 | 3931 | static ssize_t |
b807c3d0 | 3932 | tracing_read_dyn_info(struct file *filp, char __user *ubuf, |
bc0c38d1 SR |
3933 | size_t cnt, loff_t *ppos) |
3934 | { | |
a26a2a27 SR |
3935 | static char ftrace_dyn_info_buffer[1024]; |
3936 | static DEFINE_MUTEX(dyn_info_mutex); | |
bc0c38d1 | 3937 | unsigned long *p = filp->private_data; |
b807c3d0 | 3938 | char *buf = ftrace_dyn_info_buffer; |
a26a2a27 | 3939 | int size = ARRAY_SIZE(ftrace_dyn_info_buffer); |
bc0c38d1 SR |
3940 | int r; |
3941 | ||
b807c3d0 SR |
3942 | mutex_lock(&dyn_info_mutex); |
3943 | r = sprintf(buf, "%ld ", *p); | |
4bf39a94 | 3944 | |
a26a2a27 | 3945 | r += ftrace_arch_read_dyn_info(buf+r, (size-1)-r); |
b807c3d0 SR |
3946 | buf[r++] = '\n'; |
3947 | ||
3948 | r = simple_read_from_buffer(ubuf, cnt, ppos, buf, r); | |
3949 | ||
3950 | mutex_unlock(&dyn_info_mutex); | |
3951 | ||
3952 | return r; | |
bc0c38d1 SR |
3953 | } |
3954 | ||
5e2336a0 | 3955 | static const struct file_operations tracing_dyn_info_fops = { |
4bf39a94 | 3956 | .open = tracing_open_generic, |
b807c3d0 | 3957 | .read = tracing_read_dyn_info, |
bc0c38d1 SR |
3958 | }; |
3959 | #endif | |
3960 | ||
3961 | static struct dentry *d_tracer; | |
3962 | ||
3963 | struct dentry *tracing_init_dentry(void) | |
3964 | { | |
3965 | static int once; | |
3966 | ||
3967 | if (d_tracer) | |
3968 | return d_tracer; | |
3969 | ||
3e1f60b8 FW |
3970 | if (!debugfs_initialized()) |
3971 | return NULL; | |
3972 | ||
bc0c38d1 SR |
3973 | d_tracer = debugfs_create_dir("tracing", NULL); |
3974 | ||
3975 | if (!d_tracer && !once) { | |
3976 | once = 1; | |
3977 | pr_warning("Could not create debugfs directory 'tracing'\n"); | |
3978 | return NULL; | |
3979 | } | |
3980 | ||
3981 | return d_tracer; | |
3982 | } | |
3983 | ||
b04cc6b1 FW |
3984 | static struct dentry *d_percpu; |
3985 | ||
3986 | struct dentry *tracing_dentry_percpu(void) | |
3987 | { | |
3988 | static int once; | |
3989 | struct dentry *d_tracer; | |
3990 | ||
3991 | if (d_percpu) | |
3992 | return d_percpu; | |
3993 | ||
3994 | d_tracer = tracing_init_dentry(); | |
3995 | ||
3996 | if (!d_tracer) | |
3997 | return NULL; | |
3998 | ||
3999 | d_percpu = debugfs_create_dir("per_cpu", d_tracer); | |
4000 | ||
4001 | if (!d_percpu && !once) { | |
4002 | once = 1; | |
4003 | pr_warning("Could not create debugfs directory 'per_cpu'\n"); | |
4004 | return NULL; | |
4005 | } | |
4006 | ||
4007 | return d_percpu; | |
4008 | } | |
4009 | ||
4010 | static void tracing_init_debugfs_percpu(long cpu) | |
4011 | { | |
4012 | struct dentry *d_percpu = tracing_dentry_percpu(); | |
5452af66 | 4013 | struct dentry *d_cpu; |
8656e7a2 FW |
4014 | /* strlen(cpu) + MAX(log10(cpu)) + '\0' */ |
4015 | char cpu_dir[7]; | |
b04cc6b1 FW |
4016 | |
4017 | if (cpu > 999 || cpu < 0) | |
4018 | return; | |
4019 | ||
8656e7a2 FW |
4020 | sprintf(cpu_dir, "cpu%ld", cpu); |
4021 | d_cpu = debugfs_create_dir(cpu_dir, d_percpu); | |
4022 | if (!d_cpu) { | |
4023 | pr_warning("Could not create debugfs '%s' entry\n", cpu_dir); | |
4024 | return; | |
4025 | } | |
b04cc6b1 | 4026 | |
8656e7a2 | 4027 | /* per cpu trace_pipe */ |
5452af66 FW |
4028 | trace_create_file("trace_pipe", 0444, d_cpu, |
4029 | (void *) cpu, &tracing_pipe_fops); | |
b04cc6b1 FW |
4030 | |
4031 | /* per cpu trace */ | |
5452af66 FW |
4032 | trace_create_file("trace", 0644, d_cpu, |
4033 | (void *) cpu, &tracing_fops); | |
7f96f93f | 4034 | |
5452af66 FW |
4035 | trace_create_file("trace_pipe_raw", 0444, d_cpu, |
4036 | (void *) cpu, &tracing_buffers_fops); | |
7f96f93f | 4037 | |
c8d77183 SR |
4038 | trace_create_file("stats", 0444, d_cpu, |
4039 | (void *) cpu, &tracing_stats_fops); | |
b04cc6b1 FW |
4040 | } |
4041 | ||
60a11774 SR |
4042 | #ifdef CONFIG_FTRACE_SELFTEST |
4043 | /* Let selftest have access to static functions in this file */ | |
4044 | #include "trace_selftest.c" | |
4045 | #endif | |
4046 | ||
577b785f SR |
4047 | struct trace_option_dentry { |
4048 | struct tracer_opt *opt; | |
4049 | struct tracer_flags *flags; | |
4050 | struct dentry *entry; | |
4051 | }; | |
4052 | ||
4053 | static ssize_t | |
4054 | trace_options_read(struct file *filp, char __user *ubuf, size_t cnt, | |
4055 | loff_t *ppos) | |
4056 | { | |
4057 | struct trace_option_dentry *topt = filp->private_data; | |
4058 | char *buf; | |
4059 | ||
4060 | if (topt->flags->val & topt->opt->bit) | |
4061 | buf = "1\n"; | |
4062 | else | |
4063 | buf = "0\n"; | |
4064 | ||
4065 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, 2); | |
4066 | } | |
4067 | ||
4068 | static ssize_t | |
4069 | trace_options_write(struct file *filp, const char __user *ubuf, size_t cnt, | |
4070 | loff_t *ppos) | |
4071 | { | |
4072 | struct trace_option_dentry *topt = filp->private_data; | |
4073 | unsigned long val; | |
4074 | char buf[64]; | |
4075 | int ret; | |
4076 | ||
4077 | if (cnt >= sizeof(buf)) | |
4078 | return -EINVAL; | |
4079 | ||
4080 | if (copy_from_user(&buf, ubuf, cnt)) | |
4081 | return -EFAULT; | |
4082 | ||
4083 | buf[cnt] = 0; | |
4084 | ||
4085 | ret = strict_strtoul(buf, 10, &val); | |
4086 | if (ret < 0) | |
4087 | return ret; | |
4088 | ||
8d18eaaf LZ |
4089 | if (val != 0 && val != 1) |
4090 | return -EINVAL; | |
577b785f | 4091 | |
8d18eaaf | 4092 | if (!!(topt->flags->val & topt->opt->bit) != val) { |
577b785f | 4093 | mutex_lock(&trace_types_lock); |
8d18eaaf | 4094 | ret = __set_tracer_option(current_trace, topt->flags, |
c757bea9 | 4095 | topt->opt, !val); |
577b785f SR |
4096 | mutex_unlock(&trace_types_lock); |
4097 | if (ret) | |
4098 | return ret; | |
577b785f SR |
4099 | } |
4100 | ||
4101 | *ppos += cnt; | |
4102 | ||
4103 | return cnt; | |
4104 | } | |
4105 | ||
4106 | ||
4107 | static const struct file_operations trace_options_fops = { | |
4108 | .open = tracing_open_generic, | |
4109 | .read = trace_options_read, | |
4110 | .write = trace_options_write, | |
4111 | }; | |
4112 | ||
a8259075 SR |
4113 | static ssize_t |
4114 | trace_options_core_read(struct file *filp, char __user *ubuf, size_t cnt, | |
4115 | loff_t *ppos) | |
4116 | { | |
4117 | long index = (long)filp->private_data; | |
4118 | char *buf; | |
4119 | ||
4120 | if (trace_flags & (1 << index)) | |
4121 | buf = "1\n"; | |
4122 | else | |
4123 | buf = "0\n"; | |
4124 | ||
4125 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, 2); | |
4126 | } | |
4127 | ||
4128 | static ssize_t | |
4129 | trace_options_core_write(struct file *filp, const char __user *ubuf, size_t cnt, | |
4130 | loff_t *ppos) | |
4131 | { | |
4132 | long index = (long)filp->private_data; | |
4133 | char buf[64]; | |
4134 | unsigned long val; | |
4135 | int ret; | |
4136 | ||
4137 | if (cnt >= sizeof(buf)) | |
4138 | return -EINVAL; | |
4139 | ||
4140 | if (copy_from_user(&buf, ubuf, cnt)) | |
4141 | return -EFAULT; | |
4142 | ||
4143 | buf[cnt] = 0; | |
4144 | ||
4145 | ret = strict_strtoul(buf, 10, &val); | |
4146 | if (ret < 0) | |
4147 | return ret; | |
4148 | ||
f2d84b65 | 4149 | if (val != 0 && val != 1) |
a8259075 | 4150 | return -EINVAL; |
f2d84b65 | 4151 | set_tracer_flags(1 << index, val); |
a8259075 SR |
4152 | |
4153 | *ppos += cnt; | |
4154 | ||
4155 | return cnt; | |
4156 | } | |
4157 | ||
a8259075 SR |
4158 | static const struct file_operations trace_options_core_fops = { |
4159 | .open = tracing_open_generic, | |
4160 | .read = trace_options_core_read, | |
4161 | .write = trace_options_core_write, | |
4162 | }; | |
4163 | ||
5452af66 FW |
4164 | struct dentry *trace_create_file(const char *name, |
4165 | mode_t mode, | |
4166 | struct dentry *parent, | |
4167 | void *data, | |
4168 | const struct file_operations *fops) | |
4169 | { | |
4170 | struct dentry *ret; | |
4171 | ||
4172 | ret = debugfs_create_file(name, mode, parent, data, fops); | |
4173 | if (!ret) | |
4174 | pr_warning("Could not create debugfs '%s' entry\n", name); | |
4175 | ||
4176 | return ret; | |
4177 | } | |
4178 | ||
4179 | ||
a8259075 SR |
4180 | static struct dentry *trace_options_init_dentry(void) |
4181 | { | |
4182 | struct dentry *d_tracer; | |
4183 | static struct dentry *t_options; | |
4184 | ||
4185 | if (t_options) | |
4186 | return t_options; | |
4187 | ||
4188 | d_tracer = tracing_init_dentry(); | |
4189 | if (!d_tracer) | |
4190 | return NULL; | |
4191 | ||
4192 | t_options = debugfs_create_dir("options", d_tracer); | |
4193 | if (!t_options) { | |
4194 | pr_warning("Could not create debugfs directory 'options'\n"); | |
4195 | return NULL; | |
4196 | } | |
4197 | ||
4198 | return t_options; | |
4199 | } | |
4200 | ||
577b785f SR |
4201 | static void |
4202 | create_trace_option_file(struct trace_option_dentry *topt, | |
4203 | struct tracer_flags *flags, | |
4204 | struct tracer_opt *opt) | |
4205 | { | |
4206 | struct dentry *t_options; | |
577b785f SR |
4207 | |
4208 | t_options = trace_options_init_dentry(); | |
4209 | if (!t_options) | |
4210 | return; | |
4211 | ||
4212 | topt->flags = flags; | |
4213 | topt->opt = opt; | |
4214 | ||
5452af66 | 4215 | topt->entry = trace_create_file(opt->name, 0644, t_options, topt, |
577b785f SR |
4216 | &trace_options_fops); |
4217 | ||
577b785f SR |
4218 | } |
4219 | ||
4220 | static struct trace_option_dentry * | |
4221 | create_trace_option_files(struct tracer *tracer) | |
4222 | { | |
4223 | struct trace_option_dentry *topts; | |
4224 | struct tracer_flags *flags; | |
4225 | struct tracer_opt *opts; | |
4226 | int cnt; | |
4227 | ||
4228 | if (!tracer) | |
4229 | return NULL; | |
4230 | ||
4231 | flags = tracer->flags; | |
4232 | ||
4233 | if (!flags || !flags->opts) | |
4234 | return NULL; | |
4235 | ||
4236 | opts = flags->opts; | |
4237 | ||
4238 | for (cnt = 0; opts[cnt].name; cnt++) | |
4239 | ; | |
4240 | ||
0cfe8245 | 4241 | topts = kcalloc(cnt + 1, sizeof(*topts), GFP_KERNEL); |
577b785f SR |
4242 | if (!topts) |
4243 | return NULL; | |
4244 | ||
4245 | for (cnt = 0; opts[cnt].name; cnt++) | |
4246 | create_trace_option_file(&topts[cnt], flags, | |
4247 | &opts[cnt]); | |
4248 | ||
4249 | return topts; | |
4250 | } | |
4251 | ||
4252 | static void | |
4253 | destroy_trace_option_files(struct trace_option_dentry *topts) | |
4254 | { | |
4255 | int cnt; | |
4256 | ||
4257 | if (!topts) | |
4258 | return; | |
4259 | ||
4260 | for (cnt = 0; topts[cnt].opt; cnt++) { | |
4261 | if (topts[cnt].entry) | |
4262 | debugfs_remove(topts[cnt].entry); | |
4263 | } | |
4264 | ||
4265 | kfree(topts); | |
4266 | } | |
4267 | ||
a8259075 SR |
4268 | static struct dentry * |
4269 | create_trace_option_core_file(const char *option, long index) | |
4270 | { | |
4271 | struct dentry *t_options; | |
a8259075 SR |
4272 | |
4273 | t_options = trace_options_init_dentry(); | |
4274 | if (!t_options) | |
4275 | return NULL; | |
4276 | ||
5452af66 | 4277 | return trace_create_file(option, 0644, t_options, (void *)index, |
a8259075 | 4278 | &trace_options_core_fops); |
a8259075 SR |
4279 | } |
4280 | ||
4281 | static __init void create_trace_options_dir(void) | |
4282 | { | |
4283 | struct dentry *t_options; | |
a8259075 SR |
4284 | int i; |
4285 | ||
4286 | t_options = trace_options_init_dentry(); | |
4287 | if (!t_options) | |
4288 | return; | |
4289 | ||
5452af66 FW |
4290 | for (i = 0; trace_options[i]; i++) |
4291 | create_trace_option_core_file(trace_options[i], i); | |
a8259075 SR |
4292 | } |
4293 | ||
b5ad384e | 4294 | static __init int tracer_init_debugfs(void) |
bc0c38d1 SR |
4295 | { |
4296 | struct dentry *d_tracer; | |
b04cc6b1 | 4297 | int cpu; |
bc0c38d1 | 4298 | |
7e53bd42 LJ |
4299 | trace_access_lock_init(); |
4300 | ||
bc0c38d1 SR |
4301 | d_tracer = tracing_init_dentry(); |
4302 | ||
5452af66 FW |
4303 | trace_create_file("tracing_enabled", 0644, d_tracer, |
4304 | &global_trace, &tracing_ctrl_fops); | |
bc0c38d1 | 4305 | |
5452af66 FW |
4306 | trace_create_file("trace_options", 0644, d_tracer, |
4307 | NULL, &tracing_iter_fops); | |
bc0c38d1 | 4308 | |
5452af66 FW |
4309 | trace_create_file("tracing_cpumask", 0644, d_tracer, |
4310 | NULL, &tracing_cpumask_fops); | |
4311 | ||
4312 | trace_create_file("trace", 0644, d_tracer, | |
4313 | (void *) TRACE_PIPE_ALL_CPU, &tracing_fops); | |
a8259075 | 4314 | |
5452af66 FW |
4315 | trace_create_file("available_tracers", 0444, d_tracer, |
4316 | &global_trace, &show_traces_fops); | |
4317 | ||
339ae5d3 | 4318 | trace_create_file("current_tracer", 0644, d_tracer, |
5452af66 FW |
4319 | &global_trace, &set_tracer_fops); |
4320 | ||
5d4a9dba | 4321 | #ifdef CONFIG_TRACER_MAX_TRACE |
5452af66 FW |
4322 | trace_create_file("tracing_max_latency", 0644, d_tracer, |
4323 | &tracing_max_latency, &tracing_max_lat_fops); | |
0e950173 | 4324 | #endif |
5452af66 FW |
4325 | |
4326 | trace_create_file("tracing_thresh", 0644, d_tracer, | |
4327 | &tracing_thresh, &tracing_max_lat_fops); | |
a8259075 | 4328 | |
339ae5d3 | 4329 | trace_create_file("README", 0444, d_tracer, |
5452af66 FW |
4330 | NULL, &tracing_readme_fops); |
4331 | ||
4332 | trace_create_file("trace_pipe", 0444, d_tracer, | |
b04cc6b1 | 4333 | (void *) TRACE_PIPE_ALL_CPU, &tracing_pipe_fops); |
5452af66 FW |
4334 | |
4335 | trace_create_file("buffer_size_kb", 0644, d_tracer, | |
4336 | &global_trace, &tracing_entries_fops); | |
4337 | ||
4338 | trace_create_file("trace_marker", 0220, d_tracer, | |
4339 | NULL, &tracing_mark_fops); | |
5bf9a1ee | 4340 | |
69abe6a5 AP |
4341 | trace_create_file("saved_cmdlines", 0444, d_tracer, |
4342 | NULL, &tracing_saved_cmdlines_fops); | |
5bf9a1ee | 4343 | |
5079f326 Z |
4344 | trace_create_file("trace_clock", 0644, d_tracer, NULL, |
4345 | &trace_clock_fops); | |
4346 | ||
bc0c38d1 | 4347 | #ifdef CONFIG_DYNAMIC_FTRACE |
5452af66 FW |
4348 | trace_create_file("dyn_ftrace_total_info", 0444, d_tracer, |
4349 | &ftrace_update_tot_cnt, &tracing_dyn_info_fops); | |
bc0c38d1 | 4350 | #endif |
d618b3e6 IM |
4351 | #ifdef CONFIG_SYSPROF_TRACER |
4352 | init_tracer_sysprof_debugfs(d_tracer); | |
4353 | #endif | |
b04cc6b1 | 4354 | |
5452af66 FW |
4355 | create_trace_options_dir(); |
4356 | ||
b04cc6b1 FW |
4357 | for_each_tracing_cpu(cpu) |
4358 | tracing_init_debugfs_percpu(cpu); | |
4359 | ||
b5ad384e | 4360 | return 0; |
bc0c38d1 SR |
4361 | } |
4362 | ||
3f5a54e3 SR |
4363 | static int trace_panic_handler(struct notifier_block *this, |
4364 | unsigned long event, void *unused) | |
4365 | { | |
944ac425 | 4366 | if (ftrace_dump_on_oops) |
cecbca96 | 4367 | ftrace_dump(ftrace_dump_on_oops); |
3f5a54e3 SR |
4368 | return NOTIFY_OK; |
4369 | } | |
4370 | ||
4371 | static struct notifier_block trace_panic_notifier = { | |
4372 | .notifier_call = trace_panic_handler, | |
4373 | .next = NULL, | |
4374 | .priority = 150 /* priority: INT_MAX >= x >= 0 */ | |
4375 | }; | |
4376 | ||
4377 | static int trace_die_handler(struct notifier_block *self, | |
4378 | unsigned long val, | |
4379 | void *data) | |
4380 | { | |
4381 | switch (val) { | |
4382 | case DIE_OOPS: | |
944ac425 | 4383 | if (ftrace_dump_on_oops) |
cecbca96 | 4384 | ftrace_dump(ftrace_dump_on_oops); |
3f5a54e3 SR |
4385 | break; |
4386 | default: | |
4387 | break; | |
4388 | } | |
4389 | return NOTIFY_OK; | |
4390 | } | |
4391 | ||
4392 | static struct notifier_block trace_die_notifier = { | |
4393 | .notifier_call = trace_die_handler, | |
4394 | .priority = 200 | |
4395 | }; | |
4396 | ||
4397 | /* | |
4398 | * printk is set to max of 1024, we really don't need it that big. | |
4399 | * Nothing should be printing 1000 characters anyway. | |
4400 | */ | |
4401 | #define TRACE_MAX_PRINT 1000 | |
4402 | ||
4403 | /* | |
4404 | * Define here KERN_TRACE so that we have one place to modify | |
4405 | * it if we decide to change what log level the ftrace dump | |
4406 | * should be at. | |
4407 | */ | |
428aee14 | 4408 | #define KERN_TRACE KERN_EMERG |
3f5a54e3 SR |
4409 | |
4410 | static void | |
4411 | trace_printk_seq(struct trace_seq *s) | |
4412 | { | |
4413 | /* Probably should print a warning here. */ | |
4414 | if (s->len >= 1000) | |
4415 | s->len = 1000; | |
4416 | ||
4417 | /* should be zero ended, but we are paranoid. */ | |
4418 | s->buffer[s->len] = 0; | |
4419 | ||
4420 | printk(KERN_TRACE "%s", s->buffer); | |
4421 | ||
f9520750 | 4422 | trace_seq_init(s); |
3f5a54e3 SR |
4423 | } |
4424 | ||
cecbca96 FW |
4425 | static void |
4426 | __ftrace_dump(bool disable_tracing, enum ftrace_dump_mode oops_dump_mode) | |
3f5a54e3 | 4427 | { |
445c8951 | 4428 | static arch_spinlock_t ftrace_dump_lock = |
edc35bd7 | 4429 | (arch_spinlock_t)__ARCH_SPIN_LOCK_UNLOCKED; |
3f5a54e3 SR |
4430 | /* use static because iter can be a bit big for the stack */ |
4431 | static struct trace_iterator iter; | |
cf586b61 | 4432 | unsigned int old_userobj; |
3f5a54e3 | 4433 | static int dump_ran; |
d769041f SR |
4434 | unsigned long flags; |
4435 | int cnt = 0, cpu; | |
3f5a54e3 SR |
4436 | |
4437 | /* only one dump */ | |
cd891ae0 | 4438 | local_irq_save(flags); |
0199c4e6 | 4439 | arch_spin_lock(&ftrace_dump_lock); |
3f5a54e3 SR |
4440 | if (dump_ran) |
4441 | goto out; | |
4442 | ||
4443 | dump_ran = 1; | |
4444 | ||
0ee6b6cf | 4445 | tracing_off(); |
cf586b61 FW |
4446 | |
4447 | if (disable_tracing) | |
4448 | ftrace_kill(); | |
3f5a54e3 | 4449 | |
d769041f SR |
4450 | for_each_tracing_cpu(cpu) { |
4451 | atomic_inc(&global_trace.data[cpu]->disabled); | |
4452 | } | |
4453 | ||
cf586b61 FW |
4454 | old_userobj = trace_flags & TRACE_ITER_SYM_USEROBJ; |
4455 | ||
b54d3de9 TE |
4456 | /* don't look at user memory in panic mode */ |
4457 | trace_flags &= ~TRACE_ITER_SYM_USEROBJ; | |
4458 | ||
e543ad76 | 4459 | /* Simulate the iterator */ |
3f5a54e3 SR |
4460 | iter.tr = &global_trace; |
4461 | iter.trace = current_trace; | |
cecbca96 FW |
4462 | |
4463 | switch (oops_dump_mode) { | |
4464 | case DUMP_ALL: | |
4465 | iter.cpu_file = TRACE_PIPE_ALL_CPU; | |
4466 | break; | |
4467 | case DUMP_ORIG: | |
4468 | iter.cpu_file = raw_smp_processor_id(); | |
4469 | break; | |
4470 | case DUMP_NONE: | |
4471 | goto out_enable; | |
4472 | default: | |
4473 | printk(KERN_TRACE "Bad dumping mode, switching to all CPUs dump\n"); | |
4474 | iter.cpu_file = TRACE_PIPE_ALL_CPU; | |
4475 | } | |
4476 | ||
4477 | printk(KERN_TRACE "Dumping ftrace buffer:\n"); | |
3f5a54e3 SR |
4478 | |
4479 | /* | |
4480 | * We need to stop all tracing on all CPUS to read the | |
4481 | * the next buffer. This is a bit expensive, but is | |
4482 | * not done often. We fill all what we can read, | |
4483 | * and then release the locks again. | |
4484 | */ | |
4485 | ||
3f5a54e3 SR |
4486 | while (!trace_empty(&iter)) { |
4487 | ||
4488 | if (!cnt) | |
4489 | printk(KERN_TRACE "---------------------------------\n"); | |
4490 | ||
4491 | cnt++; | |
4492 | ||
4493 | /* reset all but tr, trace, and overruns */ | |
4494 | memset(&iter.seq, 0, | |
4495 | sizeof(struct trace_iterator) - | |
4496 | offsetof(struct trace_iterator, seq)); | |
4497 | iter.iter_flags |= TRACE_FILE_LAT_FMT; | |
4498 | iter.pos = -1; | |
4499 | ||
4500 | if (find_next_entry_inc(&iter) != NULL) { | |
74e7ff8c LJ |
4501 | int ret; |
4502 | ||
4503 | ret = print_trace_line(&iter); | |
4504 | if (ret != TRACE_TYPE_NO_CONSUME) | |
4505 | trace_consume(&iter); | |
3f5a54e3 SR |
4506 | } |
4507 | ||
4508 | trace_printk_seq(&iter.seq); | |
4509 | } | |
4510 | ||
4511 | if (!cnt) | |
4512 | printk(KERN_TRACE " (ftrace buffer empty)\n"); | |
4513 | else | |
4514 | printk(KERN_TRACE "---------------------------------\n"); | |
4515 | ||
cecbca96 | 4516 | out_enable: |
cf586b61 FW |
4517 | /* Re-enable tracing if requested */ |
4518 | if (!disable_tracing) { | |
4519 | trace_flags |= old_userobj; | |
4520 | ||
4521 | for_each_tracing_cpu(cpu) { | |
4522 | atomic_dec(&global_trace.data[cpu]->disabled); | |
4523 | } | |
4524 | tracing_on(); | |
4525 | } | |
4526 | ||
3f5a54e3 | 4527 | out: |
0199c4e6 | 4528 | arch_spin_unlock(&ftrace_dump_lock); |
cd891ae0 | 4529 | local_irq_restore(flags); |
3f5a54e3 SR |
4530 | } |
4531 | ||
cf586b61 | 4532 | /* By default: disable tracing after the dump */ |
cecbca96 | 4533 | void ftrace_dump(enum ftrace_dump_mode oops_dump_mode) |
cf586b61 | 4534 | { |
cecbca96 | 4535 | __ftrace_dump(true, oops_dump_mode); |
cf586b61 FW |
4536 | } |
4537 | ||
3928a8a2 | 4538 | __init static int tracer_alloc_buffers(void) |
bc0c38d1 | 4539 | { |
73c5162a | 4540 | int ring_buf_size; |
4c11d7ae | 4541 | int i; |
9e01c1b7 | 4542 | int ret = -ENOMEM; |
4c11d7ae | 4543 | |
9e01c1b7 RR |
4544 | if (!alloc_cpumask_var(&tracing_buffer_mask, GFP_KERNEL)) |
4545 | goto out; | |
4546 | ||
4547 | if (!alloc_cpumask_var(&tracing_cpumask, GFP_KERNEL)) | |
4548 | goto out_free_buffer_mask; | |
4c11d7ae | 4549 | |
73c5162a SR |
4550 | /* To save memory, keep the ring buffer size to its minimum */ |
4551 | if (ring_buffer_expanded) | |
4552 | ring_buf_size = trace_buf_size; | |
4553 | else | |
4554 | ring_buf_size = 1; | |
4555 | ||
9e01c1b7 RR |
4556 | cpumask_copy(tracing_buffer_mask, cpu_possible_mask); |
4557 | cpumask_copy(tracing_cpumask, cpu_all_mask); | |
4558 | ||
4559 | /* TODO: make the number of buffers hot pluggable with CPUS */ | |
73c5162a | 4560 | global_trace.buffer = ring_buffer_alloc(ring_buf_size, |
3928a8a2 SR |
4561 | TRACE_BUFFER_FLAGS); |
4562 | if (!global_trace.buffer) { | |
4563 | printk(KERN_ERR "tracer: failed to allocate ring buffer!\n"); | |
4564 | WARN_ON(1); | |
9e01c1b7 | 4565 | goto out_free_cpumask; |
4c11d7ae | 4566 | } |
3928a8a2 | 4567 | global_trace.entries = ring_buffer_size(global_trace.buffer); |
4c11d7ae | 4568 | |
9e01c1b7 | 4569 | |
4c11d7ae | 4570 | #ifdef CONFIG_TRACER_MAX_TRACE |
73c5162a | 4571 | max_tr.buffer = ring_buffer_alloc(ring_buf_size, |
3928a8a2 SR |
4572 | TRACE_BUFFER_FLAGS); |
4573 | if (!max_tr.buffer) { | |
4574 | printk(KERN_ERR "tracer: failed to allocate max ring buffer!\n"); | |
4575 | WARN_ON(1); | |
4576 | ring_buffer_free(global_trace.buffer); | |
9e01c1b7 | 4577 | goto out_free_cpumask; |
4c11d7ae | 4578 | } |
3928a8a2 SR |
4579 | max_tr.entries = ring_buffer_size(max_tr.buffer); |
4580 | WARN_ON(max_tr.entries != global_trace.entries); | |
a98a3c3f | 4581 | #endif |
ab46428c | 4582 | |
4c11d7ae | 4583 | /* Allocate the first page for all buffers */ |
ab46428c | 4584 | for_each_tracing_cpu(i) { |
566b0aaf | 4585 | global_trace.data[i] = &per_cpu(global_trace_cpu, i); |
9705f69e | 4586 | max_tr.data[i] = &per_cpu(max_tr_data, i); |
4c11d7ae | 4587 | } |
bc0c38d1 | 4588 | |
bc0c38d1 SR |
4589 | trace_init_cmdlines(); |
4590 | ||
43a15386 | 4591 | register_tracer(&nop_trace); |
79fb0768 | 4592 | current_trace = &nop_trace; |
b5ad384e FW |
4593 | #ifdef CONFIG_BOOT_TRACER |
4594 | register_tracer(&boot_tracer); | |
b5ad384e | 4595 | #endif |
60a11774 SR |
4596 | /* All seems OK, enable tracing */ |
4597 | tracing_disabled = 0; | |
3928a8a2 | 4598 | |
3f5a54e3 SR |
4599 | atomic_notifier_chain_register(&panic_notifier_list, |
4600 | &trace_panic_notifier); | |
4601 | ||
4602 | register_die_notifier(&trace_die_notifier); | |
2fc1dfbe FW |
4603 | |
4604 | return 0; | |
3f5a54e3 | 4605 | |
9e01c1b7 RR |
4606 | out_free_cpumask: |
4607 | free_cpumask_var(tracing_cpumask); | |
4608 | out_free_buffer_mask: | |
4609 | free_cpumask_var(tracing_buffer_mask); | |
4610 | out: | |
4611 | return ret; | |
bc0c38d1 | 4612 | } |
b2821ae6 SR |
4613 | |
4614 | __init static int clear_boot_tracer(void) | |
4615 | { | |
4616 | /* | |
4617 | * The default tracer at boot buffer is an init section. | |
4618 | * This function is called in lateinit. If we did not | |
4619 | * find the boot tracer, then clear it out, to prevent | |
4620 | * later registration from accessing the buffer that is | |
4621 | * about to be freed. | |
4622 | */ | |
4623 | if (!default_bootup_tracer) | |
4624 | return 0; | |
4625 | ||
4626 | printk(KERN_INFO "ftrace bootup tracer '%s' not registered.\n", | |
4627 | default_bootup_tracer); | |
4628 | default_bootup_tracer = NULL; | |
4629 | ||
4630 | return 0; | |
4631 | } | |
4632 | ||
b5ad384e FW |
4633 | early_initcall(tracer_alloc_buffers); |
4634 | fs_initcall(tracer_init_debugfs); | |
b2821ae6 | 4635 | late_initcall(clear_boot_tracer); |