Commit | Line | Data |
---|---|---|
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> | |
3f5a54e3 | 20 | #include <linux/notifier.h> |
2cadf913 | 21 | #include <linux/irqflags.h> |
bc0c38d1 | 22 | #include <linux/debugfs.h> |
4c11d7ae | 23 | #include <linux/pagemap.h> |
bc0c38d1 SR |
24 | #include <linux/hardirq.h> |
25 | #include <linux/linkage.h> | |
26 | #include <linux/uaccess.h> | |
2cadf913 | 27 | #include <linux/kprobes.h> |
bc0c38d1 SR |
28 | #include <linux/ftrace.h> |
29 | #include <linux/module.h> | |
30 | #include <linux/percpu.h> | |
2cadf913 | 31 | #include <linux/splice.h> |
3f5a54e3 | 32 | #include <linux/kdebug.h> |
5f0c6c03 | 33 | #include <linux/string.h> |
7e53bd42 | 34 | #include <linux/rwsem.h> |
5a0e3ad6 | 35 | #include <linux/slab.h> |
bc0c38d1 SR |
36 | #include <linux/ctype.h> |
37 | #include <linux/init.h> | |
2a2cc8f7 | 38 | #include <linux/poll.h> |
bc0c38d1 | 39 | #include <linux/fs.h> |
86387f7e | 40 | |
bc0c38d1 | 41 | #include "trace.h" |
f0868d1e | 42 | #include "trace_output.h" |
bc0c38d1 | 43 | |
73c5162a SR |
44 | /* |
45 | * On boot up, the ring buffer is set to the minimum size, so that | |
46 | * we do not waste memory on systems that are not using tracing. | |
47 | */ | |
020e5f85 | 48 | int ring_buffer_expanded; |
73c5162a | 49 | |
8e1b82e0 FW |
50 | /* |
51 | * We need to change this state when a selftest is running. | |
ff32504f FW |
52 | * A selftest will lurk into the ring-buffer to count the |
53 | * entries inserted during the selftest although some concurrent | |
5e1607a0 | 54 | * insertions into the ring-buffer such as trace_printk could occurred |
ff32504f FW |
55 | * at the same time, giving false positive or negative results. |
56 | */ | |
8e1b82e0 | 57 | static bool __read_mostly tracing_selftest_running; |
ff32504f | 58 | |
b2821ae6 SR |
59 | /* |
60 | * If a tracer is running, we do not want to run SELFTEST. | |
61 | */ | |
020e5f85 | 62 | bool __read_mostly tracing_selftest_disabled; |
b2821ae6 | 63 | |
adf9f195 FW |
64 | /* For tracers that don't implement custom flags */ |
65 | static struct tracer_opt dummy_tracer_opt[] = { | |
66 | { } | |
67 | }; | |
68 | ||
69 | static struct tracer_flags dummy_tracer_flags = { | |
70 | .val = 0, | |
71 | .opts = dummy_tracer_opt | |
72 | }; | |
73 | ||
74 | static int dummy_set_flag(u32 old_flags, u32 bit, int set) | |
75 | { | |
76 | return 0; | |
77 | } | |
0f048701 SR |
78 | |
79 | /* | |
80 | * Kill all tracing for good (never come back). | |
81 | * It is initialized to 1 but will turn to zero if the initialization | |
82 | * of the tracer is successful. But that is the only place that sets | |
83 | * this back to zero. | |
84 | */ | |
4fd27358 | 85 | static int tracing_disabled = 1; |
0f048701 | 86 | |
9288f99a | 87 | DEFINE_PER_CPU(int, ftrace_cpu_disabled); |
d769041f SR |
88 | |
89 | static inline void ftrace_disable_cpu(void) | |
90 | { | |
91 | preempt_disable(); | |
dd17c8f7 | 92 | __this_cpu_inc(ftrace_cpu_disabled); |
d769041f SR |
93 | } |
94 | ||
95 | static inline void ftrace_enable_cpu(void) | |
96 | { | |
dd17c8f7 | 97 | __this_cpu_dec(ftrace_cpu_disabled); |
d769041f SR |
98 | preempt_enable(); |
99 | } | |
100 | ||
955b61e5 | 101 | cpumask_var_t __read_mostly tracing_buffer_mask; |
ab46428c | 102 | |
944ac425 SR |
103 | /* |
104 | * ftrace_dump_on_oops - variable to dump ftrace buffer on oops | |
105 | * | |
106 | * If there is an oops (or kernel panic) and the ftrace_dump_on_oops | |
107 | * is set, then ftrace_dump is called. This will output the contents | |
108 | * of the ftrace buffers to the console. This is very useful for | |
109 | * capturing traces that lead to crashes and outputing it to a | |
110 | * serial console. | |
111 | * | |
112 | * It is default off, but you can enable it with either specifying | |
113 | * "ftrace_dump_on_oops" in the kernel command line, or setting | |
cecbca96 FW |
114 | * /proc/sys/kernel/ftrace_dump_on_oops |
115 | * Set 1 if you want to dump buffers of all CPUs | |
116 | * Set 2 if you want to dump the buffer of the CPU that triggered oops | |
944ac425 | 117 | */ |
cecbca96 FW |
118 | |
119 | enum ftrace_dump_mode ftrace_dump_on_oops; | |
944ac425 | 120 | |
b2821ae6 SR |
121 | static int tracing_set_tracer(const char *buf); |
122 | ||
ee6c2c1b LZ |
123 | #define MAX_TRACER_SIZE 100 |
124 | static char bootup_tracer_buf[MAX_TRACER_SIZE] __initdata; | |
b2821ae6 | 125 | static char *default_bootup_tracer; |
d9e54076 | 126 | |
1beee96b | 127 | static int __init set_cmdline_ftrace(char *str) |
d9e54076 | 128 | { |
ee6c2c1b | 129 | strncpy(bootup_tracer_buf, str, MAX_TRACER_SIZE); |
b2821ae6 | 130 | default_bootup_tracer = bootup_tracer_buf; |
73c5162a SR |
131 | /* We are using ftrace early, expand it */ |
132 | ring_buffer_expanded = 1; | |
d9e54076 PZ |
133 | return 1; |
134 | } | |
1beee96b | 135 | __setup("ftrace=", set_cmdline_ftrace); |
d9e54076 | 136 | |
944ac425 SR |
137 | static int __init set_ftrace_dump_on_oops(char *str) |
138 | { | |
cecbca96 FW |
139 | if (*str++ != '=' || !*str) { |
140 | ftrace_dump_on_oops = DUMP_ALL; | |
141 | return 1; | |
142 | } | |
143 | ||
144 | if (!strcmp("orig_cpu", str)) { | |
145 | ftrace_dump_on_oops = DUMP_ORIG; | |
146 | return 1; | |
147 | } | |
148 | ||
149 | return 0; | |
944ac425 SR |
150 | } |
151 | __setup("ftrace_dump_on_oops", set_ftrace_dump_on_oops); | |
60a11774 | 152 | |
cf8e3474 | 153 | unsigned long long ns2usecs(cycle_t nsec) |
bc0c38d1 SR |
154 | { |
155 | nsec += 500; | |
156 | do_div(nsec, 1000); | |
157 | return nsec; | |
158 | } | |
159 | ||
4fcdae83 SR |
160 | /* |
161 | * The global_trace is the descriptor that holds the tracing | |
162 | * buffers for the live tracing. For each CPU, it contains | |
163 | * a link list of pages that will store trace entries. The | |
164 | * page descriptor of the pages in the memory is used to hold | |
165 | * the link list by linking the lru item in the page descriptor | |
166 | * to each of the pages in the buffer per CPU. | |
167 | * | |
168 | * For each active CPU there is a data field that holds the | |
169 | * pages for the buffer for that CPU. Each CPU has the same number | |
170 | * of pages allocated for its buffer. | |
171 | */ | |
bc0c38d1 SR |
172 | static struct trace_array global_trace; |
173 | ||
174 | static DEFINE_PER_CPU(struct trace_array_cpu, global_trace_cpu); | |
175 | ||
e77405ad SR |
176 | int filter_current_check_discard(struct ring_buffer *buffer, |
177 | struct ftrace_event_call *call, void *rec, | |
eb02ce01 TZ |
178 | struct ring_buffer_event *event) |
179 | { | |
e77405ad | 180 | return filter_check_discard(call, rec, buffer, event); |
eb02ce01 | 181 | } |
17c873ec | 182 | EXPORT_SYMBOL_GPL(filter_current_check_discard); |
eb02ce01 | 183 | |
37886f6a SR |
184 | cycle_t ftrace_now(int cpu) |
185 | { | |
186 | u64 ts; | |
187 | ||
188 | /* Early boot up does not have a buffer yet */ | |
189 | if (!global_trace.buffer) | |
190 | return trace_clock_local(); | |
191 | ||
192 | ts = ring_buffer_time_stamp(global_trace.buffer, cpu); | |
193 | ring_buffer_normalize_time_stamp(global_trace.buffer, cpu, &ts); | |
194 | ||
195 | return ts; | |
196 | } | |
bc0c38d1 | 197 | |
4fcdae83 SR |
198 | /* |
199 | * The max_tr is used to snapshot the global_trace when a maximum | |
200 | * latency is reached. Some tracers will use this to store a maximum | |
201 | * trace while it continues examining live traces. | |
202 | * | |
203 | * The buffers for the max_tr are set up the same as the global_trace. | |
204 | * When a snapshot is taken, the link list of the max_tr is swapped | |
205 | * with the link list of the global_trace and the buffers are reset for | |
206 | * the global_trace so the tracing can continue. | |
207 | */ | |
bc0c38d1 SR |
208 | static struct trace_array max_tr; |
209 | ||
9705f69e | 210 | static DEFINE_PER_CPU(struct trace_array_cpu, max_tr_data); |
bc0c38d1 | 211 | |
4fcdae83 | 212 | /* tracer_enabled is used to toggle activation of a tracer */ |
26994ead | 213 | static int tracer_enabled = 1; |
4fcdae83 | 214 | |
9036990d SR |
215 | /** |
216 | * tracing_is_enabled - return tracer_enabled status | |
217 | * | |
218 | * This function is used by other tracers to know the status | |
219 | * of the tracer_enabled flag. Tracers may use this function | |
220 | * to know if it should enable their features when starting | |
221 | * up. See irqsoff tracer for an example (start_irqsoff_tracer). | |
222 | */ | |
223 | int tracing_is_enabled(void) | |
224 | { | |
225 | return tracer_enabled; | |
226 | } | |
227 | ||
4fcdae83 | 228 | /* |
3928a8a2 SR |
229 | * trace_buf_size is the size in bytes that is allocated |
230 | * for a buffer. Note, the number of bytes is always rounded | |
231 | * to page size. | |
3f5a54e3 SR |
232 | * |
233 | * This number is purposely set to a low number of 16384. | |
234 | * If the dump on oops happens, it will be much appreciated | |
235 | * to not have to wait for all that output. Anyway this can be | |
236 | * boot time and run time configurable. | |
4fcdae83 | 237 | */ |
3928a8a2 | 238 | #define TRACE_BUF_SIZE_DEFAULT 1441792UL /* 16384 * 88 (sizeof(entry)) */ |
3f5a54e3 | 239 | |
3928a8a2 | 240 | static unsigned long trace_buf_size = TRACE_BUF_SIZE_DEFAULT; |
bc0c38d1 | 241 | |
4fcdae83 | 242 | /* trace_types holds a link list of available tracers. */ |
bc0c38d1 | 243 | static struct tracer *trace_types __read_mostly; |
4fcdae83 SR |
244 | |
245 | /* current_trace points to the tracer that is currently active */ | |
bc0c38d1 | 246 | static struct tracer *current_trace __read_mostly; |
4fcdae83 | 247 | |
4fcdae83 SR |
248 | /* |
249 | * trace_types_lock is used to protect the trace_types list. | |
4fcdae83 | 250 | */ |
bc0c38d1 | 251 | static DEFINE_MUTEX(trace_types_lock); |
4fcdae83 | 252 | |
7e53bd42 LJ |
253 | /* |
254 | * serialize the access of the ring buffer | |
255 | * | |
256 | * ring buffer serializes readers, but it is low level protection. | |
257 | * The validity of the events (which returns by ring_buffer_peek() ..etc) | |
258 | * are not protected by ring buffer. | |
259 | * | |
260 | * The content of events may become garbage if we allow other process consumes | |
261 | * these events concurrently: | |
262 | * A) the page of the consumed events may become a normal page | |
263 | * (not reader page) in ring buffer, and this page will be rewrited | |
264 | * by events producer. | |
265 | * B) The page of the consumed events may become a page for splice_read, | |
266 | * and this page will be returned to system. | |
267 | * | |
268 | * These primitives allow multi process access to different cpu ring buffer | |
269 | * concurrently. | |
270 | * | |
271 | * These primitives don't distinguish read-only and read-consume access. | |
272 | * Multi read-only access are also serialized. | |
273 | */ | |
274 | ||
275 | #ifdef CONFIG_SMP | |
276 | static DECLARE_RWSEM(all_cpu_access_lock); | |
277 | static DEFINE_PER_CPU(struct mutex, cpu_access_lock); | |
278 | ||
279 | static inline void trace_access_lock(int cpu) | |
280 | { | |
281 | if (cpu == TRACE_PIPE_ALL_CPU) { | |
282 | /* gain it for accessing the whole ring buffer. */ | |
283 | down_write(&all_cpu_access_lock); | |
284 | } else { | |
285 | /* gain it for accessing a cpu ring buffer. */ | |
286 | ||
287 | /* Firstly block other trace_access_lock(TRACE_PIPE_ALL_CPU). */ | |
288 | down_read(&all_cpu_access_lock); | |
289 | ||
290 | /* Secondly block other access to this @cpu ring buffer. */ | |
291 | mutex_lock(&per_cpu(cpu_access_lock, cpu)); | |
292 | } | |
293 | } | |
294 | ||
295 | static inline void trace_access_unlock(int cpu) | |
296 | { | |
297 | if (cpu == TRACE_PIPE_ALL_CPU) { | |
298 | up_write(&all_cpu_access_lock); | |
299 | } else { | |
300 | mutex_unlock(&per_cpu(cpu_access_lock, cpu)); | |
301 | up_read(&all_cpu_access_lock); | |
302 | } | |
303 | } | |
304 | ||
305 | static inline void trace_access_lock_init(void) | |
306 | { | |
307 | int cpu; | |
308 | ||
309 | for_each_possible_cpu(cpu) | |
310 | mutex_init(&per_cpu(cpu_access_lock, cpu)); | |
311 | } | |
312 | ||
313 | #else | |
314 | ||
315 | static DEFINE_MUTEX(access_lock); | |
316 | ||
317 | static inline void trace_access_lock(int cpu) | |
318 | { | |
319 | (void)cpu; | |
320 | mutex_lock(&access_lock); | |
321 | } | |
322 | ||
323 | static inline void trace_access_unlock(int cpu) | |
324 | { | |
325 | (void)cpu; | |
326 | mutex_unlock(&access_lock); | |
327 | } | |
328 | ||
329 | static inline void trace_access_lock_init(void) | |
330 | { | |
331 | } | |
332 | ||
333 | #endif | |
334 | ||
4fcdae83 | 335 | /* trace_wait is a waitqueue for tasks blocked on trace_poll */ |
4e655519 IM |
336 | static DECLARE_WAIT_QUEUE_HEAD(trace_wait); |
337 | ||
ee6bce52 | 338 | /* trace_flags holds trace_options default values */ |
12ef7d44 | 339 | unsigned long trace_flags = TRACE_ITER_PRINT_PARENT | TRACE_ITER_PRINTK | |
a2a16d6a | 340 | TRACE_ITER_ANNOTATE | TRACE_ITER_CONTEXT_INFO | TRACE_ITER_SLEEP_TIME | |
750912fa | 341 | TRACE_ITER_GRAPH_TIME | TRACE_ITER_RECORD_CMD | TRACE_ITER_OVERWRITE; |
4e655519 | 342 | |
b8de7bd1 SR |
343 | static int trace_stop_count; |
344 | static DEFINE_SPINLOCK(tracing_start_lock); | |
345 | ||
e7e2ee89 VN |
346 | static void wakeup_work_handler(struct work_struct *work) |
347 | { | |
348 | wake_up(&trace_wait); | |
349 | } | |
350 | ||
351 | static DECLARE_DELAYED_WORK(wakeup_work, wakeup_work_handler); | |
352 | ||
4fcdae83 SR |
353 | /** |
354 | * trace_wake_up - wake up tasks waiting for trace input | |
355 | * | |
e7e2ee89 VN |
356 | * Schedules a delayed work to wake up any task that is blocked on the |
357 | * trace_wait queue. These is used with trace_poll for tasks polling the | |
358 | * trace. | |
4fcdae83 | 359 | */ |
4e655519 IM |
360 | void trace_wake_up(void) |
361 | { | |
e7e2ee89 | 362 | const unsigned long delay = msecs_to_jiffies(2); |
89f19f04 AM |
363 | |
364 | if (trace_flags & TRACE_ITER_BLOCK) | |
365 | return; | |
e7e2ee89 | 366 | schedule_delayed_work(&wakeup_work, delay); |
4e655519 | 367 | } |
bc0c38d1 | 368 | |
3928a8a2 | 369 | static int __init set_buf_size(char *str) |
bc0c38d1 | 370 | { |
3928a8a2 | 371 | unsigned long buf_size; |
c6caeeb1 | 372 | |
bc0c38d1 SR |
373 | if (!str) |
374 | return 0; | |
9d612bef | 375 | buf_size = memparse(str, &str); |
c6caeeb1 | 376 | /* nr_entries can not be zero */ |
9d612bef | 377 | if (buf_size == 0) |
c6caeeb1 | 378 | return 0; |
3928a8a2 | 379 | trace_buf_size = buf_size; |
bc0c38d1 SR |
380 | return 1; |
381 | } | |
3928a8a2 | 382 | __setup("trace_buf_size=", set_buf_size); |
bc0c38d1 | 383 | |
0e950173 TB |
384 | static int __init set_tracing_thresh(char *str) |
385 | { | |
386 | unsigned long threshhold; | |
387 | int ret; | |
388 | ||
389 | if (!str) | |
390 | return 0; | |
391 | ret = strict_strtoul(str, 0, &threshhold); | |
392 | if (ret < 0) | |
393 | return 0; | |
394 | tracing_thresh = threshhold * 1000; | |
395 | return 1; | |
396 | } | |
397 | __setup("tracing_thresh=", set_tracing_thresh); | |
398 | ||
57f50be1 SR |
399 | unsigned long nsecs_to_usecs(unsigned long nsecs) |
400 | { | |
401 | return nsecs / 1000; | |
402 | } | |
403 | ||
4fcdae83 | 404 | /* These must match the bit postions in trace_iterator_flags */ |
bc0c38d1 SR |
405 | static const char *trace_options[] = { |
406 | "print-parent", | |
407 | "sym-offset", | |
408 | "sym-addr", | |
409 | "verbose", | |
f9896bf3 | 410 | "raw", |
5e3ca0ec | 411 | "hex", |
cb0f12aa | 412 | "bin", |
2a2cc8f7 | 413 | "block", |
86387f7e | 414 | "stacktrace", |
5e1607a0 | 415 | "trace_printk", |
b2a866f9 | 416 | "ftrace_preempt", |
9f029e83 | 417 | "branch", |
12ef7d44 | 418 | "annotate", |
02b67518 | 419 | "userstacktrace", |
b54d3de9 | 420 | "sym-userobj", |
66896a85 | 421 | "printk-msg-only", |
c4a8e8be | 422 | "context-info", |
c032ef64 | 423 | "latency-format", |
be6f164a | 424 | "sleep-time", |
a2a16d6a | 425 | "graph-time", |
e870e9a1 | 426 | "record-cmd", |
750912fa | 427 | "overwrite", |
cf30cf67 | 428 | "disable_on_free", |
bc0c38d1 SR |
429 | NULL |
430 | }; | |
431 | ||
5079f326 Z |
432 | static struct { |
433 | u64 (*func)(void); | |
434 | const char *name; | |
435 | } trace_clocks[] = { | |
436 | { trace_clock_local, "local" }, | |
437 | { trace_clock_global, "global" }, | |
438 | }; | |
439 | ||
440 | int trace_clock_id; | |
441 | ||
b63f39ea | 442 | /* |
443 | * trace_parser_get_init - gets the buffer for trace parser | |
444 | */ | |
445 | int trace_parser_get_init(struct trace_parser *parser, int size) | |
446 | { | |
447 | memset(parser, 0, sizeof(*parser)); | |
448 | ||
449 | parser->buffer = kmalloc(size, GFP_KERNEL); | |
450 | if (!parser->buffer) | |
451 | return 1; | |
452 | ||
453 | parser->size = size; | |
454 | return 0; | |
455 | } | |
456 | ||
457 | /* | |
458 | * trace_parser_put - frees the buffer for trace parser | |
459 | */ | |
460 | void trace_parser_put(struct trace_parser *parser) | |
461 | { | |
462 | kfree(parser->buffer); | |
463 | } | |
464 | ||
465 | /* | |
466 | * trace_get_user - reads the user input string separated by space | |
467 | * (matched by isspace(ch)) | |
468 | * | |
469 | * For each string found the 'struct trace_parser' is updated, | |
470 | * and the function returns. | |
471 | * | |
472 | * Returns number of bytes read. | |
473 | * | |
474 | * See kernel/trace/trace.h for 'struct trace_parser' details. | |
475 | */ | |
476 | int trace_get_user(struct trace_parser *parser, const char __user *ubuf, | |
477 | size_t cnt, loff_t *ppos) | |
478 | { | |
479 | char ch; | |
480 | size_t read = 0; | |
481 | ssize_t ret; | |
482 | ||
483 | if (!*ppos) | |
484 | trace_parser_clear(parser); | |
485 | ||
486 | ret = get_user(ch, ubuf++); | |
487 | if (ret) | |
488 | goto out; | |
489 | ||
490 | read++; | |
491 | cnt--; | |
492 | ||
493 | /* | |
494 | * The parser is not finished with the last write, | |
495 | * continue reading the user input without skipping spaces. | |
496 | */ | |
497 | if (!parser->cont) { | |
498 | /* skip white space */ | |
499 | while (cnt && isspace(ch)) { | |
500 | ret = get_user(ch, ubuf++); | |
501 | if (ret) | |
502 | goto out; | |
503 | read++; | |
504 | cnt--; | |
505 | } | |
506 | ||
507 | /* only spaces were written */ | |
508 | if (isspace(ch)) { | |
509 | *ppos += read; | |
510 | ret = read; | |
511 | goto out; | |
512 | } | |
513 | ||
514 | parser->idx = 0; | |
515 | } | |
516 | ||
517 | /* read the non-space input */ | |
518 | while (cnt && !isspace(ch)) { | |
3c235a33 | 519 | if (parser->idx < parser->size - 1) |
b63f39ea | 520 | parser->buffer[parser->idx++] = ch; |
521 | else { | |
522 | ret = -EINVAL; | |
523 | goto out; | |
524 | } | |
525 | ret = get_user(ch, ubuf++); | |
526 | if (ret) | |
527 | goto out; | |
528 | read++; | |
529 | cnt--; | |
530 | } | |
531 | ||
532 | /* We either got finished input or we have to wait for another call. */ | |
533 | if (isspace(ch)) { | |
534 | parser->buffer[parser->idx] = 0; | |
535 | parser->cont = false; | |
536 | } else { | |
537 | parser->cont = true; | |
538 | parser->buffer[parser->idx++] = ch; | |
539 | } | |
540 | ||
541 | *ppos += read; | |
542 | ret = read; | |
543 | ||
544 | out: | |
545 | return ret; | |
546 | } | |
547 | ||
6c6c2796 PP |
548 | ssize_t trace_seq_to_user(struct trace_seq *s, char __user *ubuf, size_t cnt) |
549 | { | |
550 | int len; | |
551 | int ret; | |
552 | ||
2dc5d12b SR |
553 | if (!cnt) |
554 | return 0; | |
555 | ||
6c6c2796 PP |
556 | if (s->len <= s->readpos) |
557 | return -EBUSY; | |
558 | ||
559 | len = s->len - s->readpos; | |
560 | if (cnt > len) | |
561 | cnt = len; | |
562 | ret = copy_to_user(ubuf, s->buffer + s->readpos, cnt); | |
2dc5d12b | 563 | if (ret == cnt) |
6c6c2796 PP |
564 | return -EFAULT; |
565 | ||
2dc5d12b SR |
566 | cnt -= ret; |
567 | ||
e74da523 | 568 | s->readpos += cnt; |
6c6c2796 | 569 | return cnt; |
214023c3 SR |
570 | } |
571 | ||
b8b94265 | 572 | static ssize_t trace_seq_to_buffer(struct trace_seq *s, void *buf, size_t cnt) |
3c56819b EGM |
573 | { |
574 | int len; | |
575 | void *ret; | |
576 | ||
577 | if (s->len <= s->readpos) | |
578 | return -EBUSY; | |
579 | ||
580 | len = s->len - s->readpos; | |
581 | if (cnt > len) | |
582 | cnt = len; | |
583 | ret = memcpy(buf, s->buffer + s->readpos, cnt); | |
584 | if (!ret) | |
585 | return -EFAULT; | |
586 | ||
e74da523 | 587 | s->readpos += cnt; |
3c56819b EGM |
588 | return cnt; |
589 | } | |
590 | ||
5d4a9dba SR |
591 | /* |
592 | * ftrace_max_lock is used to protect the swapping of buffers | |
593 | * when taking a max snapshot. The buffers themselves are | |
594 | * protected by per_cpu spinlocks. But the action of the swap | |
595 | * needs its own lock. | |
596 | * | |
445c8951 | 597 | * This is defined as a arch_spinlock_t in order to help |
5d4a9dba SR |
598 | * with performance when lockdep debugging is enabled. |
599 | * | |
600 | * It is also used in other places outside the update_max_tr | |
601 | * so it needs to be defined outside of the | |
602 | * CONFIG_TRACER_MAX_TRACE. | |
603 | */ | |
445c8951 | 604 | static arch_spinlock_t ftrace_max_lock = |
edc35bd7 | 605 | (arch_spinlock_t)__ARCH_SPIN_LOCK_UNLOCKED; |
5d4a9dba | 606 | |
0e950173 TB |
607 | unsigned long __read_mostly tracing_thresh; |
608 | ||
5d4a9dba SR |
609 | #ifdef CONFIG_TRACER_MAX_TRACE |
610 | unsigned long __read_mostly tracing_max_latency; | |
5d4a9dba SR |
611 | |
612 | /* | |
613 | * Copy the new maximum trace into the separate maximum-trace | |
614 | * structure. (this way the maximum trace is permanently saved, | |
615 | * for later retrieval via /sys/kernel/debug/tracing/latency_trace) | |
616 | */ | |
617 | static void | |
618 | __update_max_tr(struct trace_array *tr, struct task_struct *tsk, int cpu) | |
619 | { | |
620 | struct trace_array_cpu *data = tr->data[cpu]; | |
1acaa1b2 | 621 | struct trace_array_cpu *max_data; |
5d4a9dba SR |
622 | |
623 | max_tr.cpu = cpu; | |
624 | max_tr.time_start = data->preempt_timestamp; | |
625 | ||
8248ac05 SR |
626 | max_data = max_tr.data[cpu]; |
627 | max_data->saved_latency = tracing_max_latency; | |
628 | max_data->critical_start = data->critical_start; | |
629 | max_data->critical_end = data->critical_end; | |
5d4a9dba | 630 | |
1acaa1b2 | 631 | memcpy(max_data->comm, tsk->comm, TASK_COMM_LEN); |
8248ac05 SR |
632 | max_data->pid = tsk->pid; |
633 | max_data->uid = task_uid(tsk); | |
634 | max_data->nice = tsk->static_prio - 20 - MAX_RT_PRIO; | |
635 | max_data->policy = tsk->policy; | |
636 | max_data->rt_priority = tsk->rt_priority; | |
5d4a9dba SR |
637 | |
638 | /* record this tasks comm */ | |
639 | tracing_record_cmdline(tsk); | |
640 | } | |
641 | ||
4fcdae83 SR |
642 | /** |
643 | * update_max_tr - snapshot all trace buffers from global_trace to max_tr | |
644 | * @tr: tracer | |
645 | * @tsk: the task with the latency | |
646 | * @cpu: The cpu that initiated the trace. | |
647 | * | |
648 | * Flip the buffers between the @tr and the max_tr and record information | |
649 | * about which task was the cause of this latency. | |
650 | */ | |
e309b41d | 651 | void |
bc0c38d1 SR |
652 | update_max_tr(struct trace_array *tr, struct task_struct *tsk, int cpu) |
653 | { | |
3928a8a2 | 654 | struct ring_buffer *buf = tr->buffer; |
bc0c38d1 | 655 | |
b8de7bd1 SR |
656 | if (trace_stop_count) |
657 | return; | |
658 | ||
4c11d7ae | 659 | WARN_ON_ONCE(!irqs_disabled()); |
ef710e10 KM |
660 | if (!current_trace->use_max_tr) { |
661 | WARN_ON_ONCE(1); | |
662 | return; | |
663 | } | |
0199c4e6 | 664 | arch_spin_lock(&ftrace_max_lock); |
3928a8a2 SR |
665 | |
666 | tr->buffer = max_tr.buffer; | |
667 | max_tr.buffer = buf; | |
668 | ||
bc0c38d1 | 669 | __update_max_tr(tr, tsk, cpu); |
0199c4e6 | 670 | arch_spin_unlock(&ftrace_max_lock); |
bc0c38d1 SR |
671 | } |
672 | ||
673 | /** | |
674 | * update_max_tr_single - only copy one trace over, and reset the rest | |
675 | * @tr - tracer | |
676 | * @tsk - task with the latency | |
677 | * @cpu - the cpu of the buffer to copy. | |
4fcdae83 SR |
678 | * |
679 | * Flip the trace of a single CPU buffer between the @tr and the max_tr. | |
bc0c38d1 | 680 | */ |
e309b41d | 681 | void |
bc0c38d1 SR |
682 | update_max_tr_single(struct trace_array *tr, struct task_struct *tsk, int cpu) |
683 | { | |
3928a8a2 | 684 | int ret; |
bc0c38d1 | 685 | |
b8de7bd1 SR |
686 | if (trace_stop_count) |
687 | return; | |
688 | ||
4c11d7ae | 689 | WARN_ON_ONCE(!irqs_disabled()); |
ef710e10 KM |
690 | if (!current_trace->use_max_tr) { |
691 | WARN_ON_ONCE(1); | |
692 | return; | |
693 | } | |
694 | ||
0199c4e6 | 695 | arch_spin_lock(&ftrace_max_lock); |
bc0c38d1 | 696 | |
d769041f SR |
697 | ftrace_disable_cpu(); |
698 | ||
3928a8a2 SR |
699 | ret = ring_buffer_swap_cpu(max_tr.buffer, tr->buffer, cpu); |
700 | ||
e8165dbb SR |
701 | if (ret == -EBUSY) { |
702 | /* | |
703 | * We failed to swap the buffer due to a commit taking | |
704 | * place on this CPU. We fail to record, but we reset | |
705 | * the max trace buffer (no one writes directly to it) | |
706 | * and flag that it failed. | |
707 | */ | |
708 | trace_array_printk(&max_tr, _THIS_IP_, | |
709 | "Failed to swap buffers due to commit in progress\n"); | |
710 | } | |
711 | ||
d769041f SR |
712 | ftrace_enable_cpu(); |
713 | ||
e8165dbb | 714 | WARN_ON_ONCE(ret && ret != -EAGAIN && ret != -EBUSY); |
bc0c38d1 SR |
715 | |
716 | __update_max_tr(tr, tsk, cpu); | |
0199c4e6 | 717 | arch_spin_unlock(&ftrace_max_lock); |
bc0c38d1 | 718 | } |
5d4a9dba | 719 | #endif /* CONFIG_TRACER_MAX_TRACE */ |
bc0c38d1 | 720 | |
4fcdae83 SR |
721 | /** |
722 | * register_tracer - register a tracer with the ftrace system. | |
723 | * @type - the plugin for the tracer | |
724 | * | |
725 | * Register a new plugin tracer. | |
726 | */ | |
bc0c38d1 | 727 | int register_tracer(struct tracer *type) |
e7669b8e HE |
728 | __releases(kernel_lock) |
729 | __acquires(kernel_lock) | |
bc0c38d1 SR |
730 | { |
731 | struct tracer *t; | |
bc0c38d1 SR |
732 | int ret = 0; |
733 | ||
734 | if (!type->name) { | |
735 | pr_info("Tracer must have a name\n"); | |
736 | return -1; | |
737 | } | |
738 | ||
24a461d5 | 739 | if (strlen(type->name) >= MAX_TRACER_SIZE) { |
ee6c2c1b LZ |
740 | pr_info("Tracer has a name longer than %d\n", MAX_TRACER_SIZE); |
741 | return -1; | |
742 | } | |
743 | ||
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; |
4a0b1665 SR |
784 | |
785 | /* If we expanded the buffers, make sure the max is expanded too */ | |
786 | if (ring_buffer_expanded && type->use_max_tr) | |
787 | ring_buffer_resize(max_tr.buffer, trace_buf_size); | |
788 | ||
60a11774 SR |
789 | /* the test is responsible for initializing and enabling */ |
790 | pr_info("Testing tracer %s: ", type->name); | |
791 | ret = type->selftest(type, tr); | |
792 | /* the test is responsible for resetting too */ | |
793 | current_trace = saved_tracer; | |
60a11774 SR |
794 | if (ret) { |
795 | printk(KERN_CONT "FAILED!\n"); | |
796 | goto out; | |
797 | } | |
1d4db00a | 798 | /* Only reset on passing, to avoid touching corrupted buffers */ |
76f0d073 | 799 | tracing_reset_online_cpus(tr); |
86fa2f60 | 800 | |
4a0b1665 SR |
801 | /* Shrink the max buffer again */ |
802 | if (ring_buffer_expanded && type->use_max_tr) | |
803 | ring_buffer_resize(max_tr.buffer, 1); | |
804 | ||
60a11774 SR |
805 | printk(KERN_CONT "PASSED\n"); |
806 | } | |
807 | #endif | |
808 | ||
bc0c38d1 SR |
809 | type->next = trace_types; |
810 | trace_types = type; | |
60a11774 | 811 | |
bc0c38d1 | 812 | out: |
8e1b82e0 | 813 | tracing_selftest_running = false; |
bc0c38d1 SR |
814 | mutex_unlock(&trace_types_lock); |
815 | ||
dac74940 SR |
816 | if (ret || !default_bootup_tracer) |
817 | goto out_unlock; | |
818 | ||
ee6c2c1b | 819 | if (strncmp(default_bootup_tracer, type->name, MAX_TRACER_SIZE)) |
dac74940 SR |
820 | goto out_unlock; |
821 | ||
822 | printk(KERN_INFO "Starting tracer '%s'\n", type->name); | |
823 | /* Do we want this tracer to start on bootup? */ | |
824 | tracing_set_tracer(type->name); | |
825 | default_bootup_tracer = NULL; | |
826 | /* disable other selftests, since this will break it. */ | |
827 | tracing_selftest_disabled = 1; | |
b2821ae6 | 828 | #ifdef CONFIG_FTRACE_STARTUP_TEST |
dac74940 SR |
829 | printk(KERN_INFO "Disabling FTRACE selftests due to running tracer '%s'\n", |
830 | type->name); | |
b2821ae6 | 831 | #endif |
b2821ae6 | 832 | |
dac74940 | 833 | out_unlock: |
bc0c38d1 SR |
834 | return ret; |
835 | } | |
836 | ||
837 | void unregister_tracer(struct tracer *type) | |
838 | { | |
839 | struct tracer **t; | |
bc0c38d1 SR |
840 | |
841 | mutex_lock(&trace_types_lock); | |
842 | for (t = &trace_types; *t; t = &(*t)->next) { | |
843 | if (*t == type) | |
844 | goto found; | |
845 | } | |
ee6c2c1b | 846 | pr_info("Tracer %s not registered\n", type->name); |
bc0c38d1 SR |
847 | goto out; |
848 | ||
849 | found: | |
850 | *t = (*t)->next; | |
b5db03c4 ACM |
851 | |
852 | if (type == current_trace && tracer_enabled) { | |
853 | tracer_enabled = 0; | |
854 | tracing_stop(); | |
855 | if (current_trace->stop) | |
856 | current_trace->stop(&global_trace); | |
857 | current_trace = &nop_trace; | |
858 | } | |
ee6c2c1b | 859 | out: |
bc0c38d1 SR |
860 | mutex_unlock(&trace_types_lock); |
861 | } | |
862 | ||
283740c6 | 863 | static void __tracing_reset(struct ring_buffer *buffer, int cpu) |
bc0c38d1 | 864 | { |
d769041f | 865 | ftrace_disable_cpu(); |
283740c6 | 866 | ring_buffer_reset_cpu(buffer, cpu); |
d769041f | 867 | ftrace_enable_cpu(); |
bc0c38d1 SR |
868 | } |
869 | ||
f633903a SR |
870 | void tracing_reset(struct trace_array *tr, int cpu) |
871 | { | |
872 | struct ring_buffer *buffer = tr->buffer; | |
873 | ||
874 | ring_buffer_record_disable(buffer); | |
875 | ||
876 | /* Make sure all commits have finished */ | |
877 | synchronize_sched(); | |
283740c6 | 878 | __tracing_reset(buffer, cpu); |
f633903a SR |
879 | |
880 | ring_buffer_record_enable(buffer); | |
881 | } | |
882 | ||
213cc060 PE |
883 | void tracing_reset_online_cpus(struct trace_array *tr) |
884 | { | |
621968cd | 885 | struct ring_buffer *buffer = tr->buffer; |
213cc060 PE |
886 | int cpu; |
887 | ||
621968cd SR |
888 | ring_buffer_record_disable(buffer); |
889 | ||
890 | /* Make sure all commits have finished */ | |
891 | synchronize_sched(); | |
892 | ||
213cc060 PE |
893 | tr->time_start = ftrace_now(tr->cpu); |
894 | ||
895 | for_each_online_cpu(cpu) | |
283740c6 | 896 | __tracing_reset(buffer, cpu); |
621968cd SR |
897 | |
898 | ring_buffer_record_enable(buffer); | |
213cc060 PE |
899 | } |
900 | ||
9456f0fa SR |
901 | void tracing_reset_current(int cpu) |
902 | { | |
903 | tracing_reset(&global_trace, cpu); | |
904 | } | |
905 | ||
906 | void tracing_reset_current_online_cpus(void) | |
907 | { | |
908 | tracing_reset_online_cpus(&global_trace); | |
909 | } | |
910 | ||
bc0c38d1 | 911 | #define SAVED_CMDLINES 128 |
2c7eea4c | 912 | #define NO_CMDLINE_MAP UINT_MAX |
bc0c38d1 SR |
913 | static unsigned map_pid_to_cmdline[PID_MAX_DEFAULT+1]; |
914 | static unsigned map_cmdline_to_pid[SAVED_CMDLINES]; | |
915 | static char saved_cmdlines[SAVED_CMDLINES][TASK_COMM_LEN]; | |
916 | static int cmdline_idx; | |
edc35bd7 | 917 | static arch_spinlock_t trace_cmdline_lock = __ARCH_SPIN_LOCK_UNLOCKED; |
25b0b44a | 918 | |
25b0b44a | 919 | /* temporary disable recording */ |
4fd27358 | 920 | static atomic_t trace_record_cmdline_disabled __read_mostly; |
bc0c38d1 SR |
921 | |
922 | static void trace_init_cmdlines(void) | |
923 | { | |
2c7eea4c TG |
924 | memset(&map_pid_to_cmdline, NO_CMDLINE_MAP, sizeof(map_pid_to_cmdline)); |
925 | memset(&map_cmdline_to_pid, NO_CMDLINE_MAP, sizeof(map_cmdline_to_pid)); | |
bc0c38d1 SR |
926 | cmdline_idx = 0; |
927 | } | |
928 | ||
b5130b1e CE |
929 | int is_tracing_stopped(void) |
930 | { | |
931 | return trace_stop_count; | |
932 | } | |
933 | ||
69bb54ec SR |
934 | /** |
935 | * ftrace_off_permanent - disable all ftrace code permanently | |
936 | * | |
937 | * This should only be called when a serious anomally has | |
938 | * been detected. This will turn off the function tracing, | |
939 | * ring buffers, and other tracing utilites. It takes no | |
940 | * locks and can be called from any context. | |
941 | */ | |
942 | void ftrace_off_permanent(void) | |
943 | { | |
944 | tracing_disabled = 1; | |
945 | ftrace_stop(); | |
946 | tracing_off_permanent(); | |
947 | } | |
948 | ||
0f048701 SR |
949 | /** |
950 | * tracing_start - quick start of the tracer | |
951 | * | |
952 | * If tracing is enabled but was stopped by tracing_stop, | |
953 | * this will start the tracer back up. | |
954 | */ | |
955 | void tracing_start(void) | |
956 | { | |
957 | struct ring_buffer *buffer; | |
958 | unsigned long flags; | |
959 | ||
960 | if (tracing_disabled) | |
961 | return; | |
962 | ||
963 | spin_lock_irqsave(&tracing_start_lock, flags); | |
b06a8301 SR |
964 | if (--trace_stop_count) { |
965 | if (trace_stop_count < 0) { | |
966 | /* Someone screwed up their debugging */ | |
967 | WARN_ON_ONCE(1); | |
968 | trace_stop_count = 0; | |
969 | } | |
0f048701 SR |
970 | goto out; |
971 | } | |
972 | ||
a2f80714 SR |
973 | /* Prevent the buffers from switching */ |
974 | arch_spin_lock(&ftrace_max_lock); | |
0f048701 SR |
975 | |
976 | buffer = global_trace.buffer; | |
977 | if (buffer) | |
978 | ring_buffer_record_enable(buffer); | |
979 | ||
980 | buffer = max_tr.buffer; | |
981 | if (buffer) | |
982 | ring_buffer_record_enable(buffer); | |
983 | ||
a2f80714 SR |
984 | arch_spin_unlock(&ftrace_max_lock); |
985 | ||
0f048701 SR |
986 | ftrace_start(); |
987 | out: | |
988 | spin_unlock_irqrestore(&tracing_start_lock, flags); | |
989 | } | |
990 | ||
991 | /** | |
992 | * tracing_stop - quick stop of the tracer | |
993 | * | |
994 | * Light weight way to stop tracing. Use in conjunction with | |
995 | * tracing_start. | |
996 | */ | |
997 | void tracing_stop(void) | |
998 | { | |
999 | struct ring_buffer *buffer; | |
1000 | unsigned long flags; | |
1001 | ||
1002 | ftrace_stop(); | |
1003 | spin_lock_irqsave(&tracing_start_lock, flags); | |
1004 | if (trace_stop_count++) | |
1005 | goto out; | |
1006 | ||
a2f80714 SR |
1007 | /* Prevent the buffers from switching */ |
1008 | arch_spin_lock(&ftrace_max_lock); | |
1009 | ||
0f048701 SR |
1010 | buffer = global_trace.buffer; |
1011 | if (buffer) | |
1012 | ring_buffer_record_disable(buffer); | |
1013 | ||
1014 | buffer = max_tr.buffer; | |
1015 | if (buffer) | |
1016 | ring_buffer_record_disable(buffer); | |
1017 | ||
a2f80714 SR |
1018 | arch_spin_unlock(&ftrace_max_lock); |
1019 | ||
0f048701 SR |
1020 | out: |
1021 | spin_unlock_irqrestore(&tracing_start_lock, flags); | |
1022 | } | |
1023 | ||
e309b41d | 1024 | void trace_stop_cmdline_recording(void); |
bc0c38d1 | 1025 | |
e309b41d | 1026 | static void trace_save_cmdline(struct task_struct *tsk) |
bc0c38d1 | 1027 | { |
a635cf04 | 1028 | unsigned pid, idx; |
bc0c38d1 SR |
1029 | |
1030 | if (!tsk->pid || unlikely(tsk->pid > PID_MAX_DEFAULT)) | |
1031 | return; | |
1032 | ||
1033 | /* | |
1034 | * It's not the end of the world if we don't get | |
1035 | * the lock, but we also don't want to spin | |
1036 | * nor do we want to disable interrupts, | |
1037 | * so if we miss here, then better luck next time. | |
1038 | */ | |
0199c4e6 | 1039 | if (!arch_spin_trylock(&trace_cmdline_lock)) |
bc0c38d1 SR |
1040 | return; |
1041 | ||
1042 | idx = map_pid_to_cmdline[tsk->pid]; | |
2c7eea4c | 1043 | if (idx == NO_CMDLINE_MAP) { |
bc0c38d1 SR |
1044 | idx = (cmdline_idx + 1) % SAVED_CMDLINES; |
1045 | ||
a635cf04 CE |
1046 | /* |
1047 | * Check whether the cmdline buffer at idx has a pid | |
1048 | * mapped. We are going to overwrite that entry so we | |
1049 | * need to clear the map_pid_to_cmdline. Otherwise we | |
1050 | * would read the new comm for the old pid. | |
1051 | */ | |
1052 | pid = map_cmdline_to_pid[idx]; | |
1053 | if (pid != NO_CMDLINE_MAP) | |
1054 | map_pid_to_cmdline[pid] = NO_CMDLINE_MAP; | |
bc0c38d1 | 1055 | |
a635cf04 | 1056 | map_cmdline_to_pid[idx] = tsk->pid; |
bc0c38d1 SR |
1057 | map_pid_to_cmdline[tsk->pid] = idx; |
1058 | ||
1059 | cmdline_idx = idx; | |
1060 | } | |
1061 | ||
1062 | memcpy(&saved_cmdlines[idx], tsk->comm, TASK_COMM_LEN); | |
1063 | ||
0199c4e6 | 1064 | arch_spin_unlock(&trace_cmdline_lock); |
bc0c38d1 SR |
1065 | } |
1066 | ||
4ca53085 | 1067 | void trace_find_cmdline(int pid, char comm[]) |
bc0c38d1 | 1068 | { |
bc0c38d1 SR |
1069 | unsigned map; |
1070 | ||
4ca53085 SR |
1071 | if (!pid) { |
1072 | strcpy(comm, "<idle>"); | |
1073 | return; | |
1074 | } | |
bc0c38d1 | 1075 | |
74bf4076 SR |
1076 | if (WARN_ON_ONCE(pid < 0)) { |
1077 | strcpy(comm, "<XXX>"); | |
1078 | return; | |
1079 | } | |
1080 | ||
4ca53085 SR |
1081 | if (pid > PID_MAX_DEFAULT) { |
1082 | strcpy(comm, "<...>"); | |
1083 | return; | |
1084 | } | |
bc0c38d1 | 1085 | |
5b6045a9 | 1086 | preempt_disable(); |
0199c4e6 | 1087 | arch_spin_lock(&trace_cmdline_lock); |
bc0c38d1 | 1088 | map = map_pid_to_cmdline[pid]; |
50d88758 TG |
1089 | if (map != NO_CMDLINE_MAP) |
1090 | strcpy(comm, saved_cmdlines[map]); | |
1091 | else | |
1092 | strcpy(comm, "<...>"); | |
bc0c38d1 | 1093 | |
0199c4e6 | 1094 | arch_spin_unlock(&trace_cmdline_lock); |
5b6045a9 | 1095 | preempt_enable(); |
bc0c38d1 SR |
1096 | } |
1097 | ||
e309b41d | 1098 | void tracing_record_cmdline(struct task_struct *tsk) |
bc0c38d1 | 1099 | { |
18aecd36 TG |
1100 | if (atomic_read(&trace_record_cmdline_disabled) || !tracer_enabled || |
1101 | !tracing_is_on()) | |
bc0c38d1 SR |
1102 | return; |
1103 | ||
1104 | trace_save_cmdline(tsk); | |
1105 | } | |
1106 | ||
45dcd8b8 | 1107 | void |
38697053 SR |
1108 | tracing_generic_entry_update(struct trace_entry *entry, unsigned long flags, |
1109 | int pc) | |
bc0c38d1 SR |
1110 | { |
1111 | struct task_struct *tsk = current; | |
bc0c38d1 | 1112 | |
777e208d SR |
1113 | entry->preempt_count = pc & 0xff; |
1114 | entry->pid = (tsk) ? tsk->pid : 0; | |
a3a4a5ac | 1115 | entry->padding = 0; |
777e208d | 1116 | entry->flags = |
9244489a | 1117 | #ifdef CONFIG_TRACE_IRQFLAGS_SUPPORT |
2e2ca155 | 1118 | (irqs_disabled_flags(flags) ? TRACE_FLAG_IRQS_OFF : 0) | |
9244489a SR |
1119 | #else |
1120 | TRACE_FLAG_IRQS_NOSUPPORT | | |
1121 | #endif | |
bc0c38d1 SR |
1122 | ((pc & HARDIRQ_MASK) ? TRACE_FLAG_HARDIRQ : 0) | |
1123 | ((pc & SOFTIRQ_MASK) ? TRACE_FLAG_SOFTIRQ : 0) | | |
1124 | (need_resched() ? TRACE_FLAG_NEED_RESCHED : 0); | |
1125 | } | |
f413cdb8 | 1126 | EXPORT_SYMBOL_GPL(tracing_generic_entry_update); |
bc0c38d1 | 1127 | |
e77405ad SR |
1128 | struct ring_buffer_event * |
1129 | trace_buffer_lock_reserve(struct ring_buffer *buffer, | |
1130 | int type, | |
1131 | unsigned long len, | |
1132 | unsigned long flags, int pc) | |
51a763dd ACM |
1133 | { |
1134 | struct ring_buffer_event *event; | |
1135 | ||
e77405ad | 1136 | event = ring_buffer_lock_reserve(buffer, len); |
51a763dd ACM |
1137 | if (event != NULL) { |
1138 | struct trace_entry *ent = ring_buffer_event_data(event); | |
1139 | ||
1140 | tracing_generic_entry_update(ent, flags, pc); | |
1141 | ent->type = type; | |
1142 | } | |
1143 | ||
1144 | return event; | |
1145 | } | |
51a763dd | 1146 | |
e77405ad SR |
1147 | static inline void |
1148 | __trace_buffer_unlock_commit(struct ring_buffer *buffer, | |
1149 | struct ring_buffer_event *event, | |
1150 | unsigned long flags, int pc, | |
1151 | int wake) | |
51a763dd | 1152 | { |
e77405ad | 1153 | ring_buffer_unlock_commit(buffer, event); |
51a763dd | 1154 | |
e77405ad SR |
1155 | ftrace_trace_stack(buffer, flags, 6, pc); |
1156 | ftrace_trace_userstack(buffer, flags, pc); | |
07edf712 FW |
1157 | |
1158 | if (wake) | |
1159 | trace_wake_up(); | |
1160 | } | |
1161 | ||
e77405ad SR |
1162 | void trace_buffer_unlock_commit(struct ring_buffer *buffer, |
1163 | struct ring_buffer_event *event, | |
1164 | unsigned long flags, int pc) | |
07edf712 | 1165 | { |
e77405ad | 1166 | __trace_buffer_unlock_commit(buffer, event, flags, pc, 1); |
51a763dd ACM |
1167 | } |
1168 | ||
ef5580d0 | 1169 | struct ring_buffer_event * |
e77405ad SR |
1170 | trace_current_buffer_lock_reserve(struct ring_buffer **current_rb, |
1171 | int type, unsigned long len, | |
ef5580d0 SR |
1172 | unsigned long flags, int pc) |
1173 | { | |
e77405ad SR |
1174 | *current_rb = global_trace.buffer; |
1175 | return trace_buffer_lock_reserve(*current_rb, | |
ef5580d0 SR |
1176 | type, len, flags, pc); |
1177 | } | |
94487d6d | 1178 | EXPORT_SYMBOL_GPL(trace_current_buffer_lock_reserve); |
ef5580d0 | 1179 | |
e77405ad SR |
1180 | void trace_current_buffer_unlock_commit(struct ring_buffer *buffer, |
1181 | struct ring_buffer_event *event, | |
ef5580d0 SR |
1182 | unsigned long flags, int pc) |
1183 | { | |
e77405ad | 1184 | __trace_buffer_unlock_commit(buffer, event, flags, pc, 1); |
07edf712 | 1185 | } |
94487d6d | 1186 | EXPORT_SYMBOL_GPL(trace_current_buffer_unlock_commit); |
07edf712 | 1187 | |
e77405ad SR |
1188 | void trace_nowake_buffer_unlock_commit(struct ring_buffer *buffer, |
1189 | struct ring_buffer_event *event, | |
1190 | unsigned long flags, int pc) | |
07edf712 | 1191 | { |
e77405ad | 1192 | __trace_buffer_unlock_commit(buffer, event, flags, pc, 0); |
77d9f465 | 1193 | } |
94487d6d | 1194 | EXPORT_SYMBOL_GPL(trace_nowake_buffer_unlock_commit); |
77d9f465 | 1195 | |
1fd8df2c MH |
1196 | void trace_nowake_buffer_unlock_commit_regs(struct ring_buffer *buffer, |
1197 | struct ring_buffer_event *event, | |
1198 | unsigned long flags, int pc, | |
1199 | struct pt_regs *regs) | |
1200 | { | |
1201 | ring_buffer_unlock_commit(buffer, event); | |
1202 | ||
1203 | ftrace_trace_stack_regs(buffer, flags, 0, pc, regs); | |
1204 | ftrace_trace_userstack(buffer, flags, pc); | |
1205 | } | |
1206 | EXPORT_SYMBOL_GPL(trace_nowake_buffer_unlock_commit_regs); | |
1207 | ||
e77405ad SR |
1208 | void trace_current_buffer_discard_commit(struct ring_buffer *buffer, |
1209 | struct ring_buffer_event *event) | |
77d9f465 | 1210 | { |
e77405ad | 1211 | ring_buffer_discard_commit(buffer, event); |
ef5580d0 | 1212 | } |
12acd473 | 1213 | EXPORT_SYMBOL_GPL(trace_current_buffer_discard_commit); |
ef5580d0 | 1214 | |
e309b41d | 1215 | void |
7be42151 | 1216 | trace_function(struct trace_array *tr, |
38697053 SR |
1217 | unsigned long ip, unsigned long parent_ip, unsigned long flags, |
1218 | int pc) | |
bc0c38d1 | 1219 | { |
e1112b4d | 1220 | struct ftrace_event_call *call = &event_function; |
e77405ad | 1221 | struct ring_buffer *buffer = tr->buffer; |
3928a8a2 | 1222 | struct ring_buffer_event *event; |
777e208d | 1223 | struct ftrace_entry *entry; |
bc0c38d1 | 1224 | |
d769041f | 1225 | /* If we are reading the ring buffer, don't trace */ |
dd17c8f7 | 1226 | if (unlikely(__this_cpu_read(ftrace_cpu_disabled))) |
d769041f SR |
1227 | return; |
1228 | ||
e77405ad | 1229 | event = trace_buffer_lock_reserve(buffer, TRACE_FN, sizeof(*entry), |
51a763dd | 1230 | flags, pc); |
3928a8a2 SR |
1231 | if (!event) |
1232 | return; | |
1233 | entry = ring_buffer_event_data(event); | |
777e208d SR |
1234 | entry->ip = ip; |
1235 | entry->parent_ip = parent_ip; | |
e1112b4d | 1236 | |
e77405ad SR |
1237 | if (!filter_check_discard(call, entry, buffer, event)) |
1238 | ring_buffer_unlock_commit(buffer, event); | |
bc0c38d1 SR |
1239 | } |
1240 | ||
e309b41d | 1241 | void |
2e0f5761 | 1242 | ftrace(struct trace_array *tr, struct trace_array_cpu *data, |
38697053 SR |
1243 | unsigned long ip, unsigned long parent_ip, unsigned long flags, |
1244 | int pc) | |
2e0f5761 IM |
1245 | { |
1246 | if (likely(!atomic_read(&data->disabled))) | |
7be42151 | 1247 | trace_function(tr, ip, parent_ip, flags, pc); |
2e0f5761 IM |
1248 | } |
1249 | ||
c0a0d0d3 | 1250 | #ifdef CONFIG_STACKTRACE |
e77405ad | 1251 | static void __ftrace_trace_stack(struct ring_buffer *buffer, |
53614991 | 1252 | unsigned long flags, |
1fd8df2c | 1253 | int skip, int pc, struct pt_regs *regs) |
86387f7e | 1254 | { |
e1112b4d | 1255 | struct ftrace_event_call *call = &event_kernel_stack; |
3928a8a2 | 1256 | struct ring_buffer_event *event; |
777e208d | 1257 | struct stack_entry *entry; |
86387f7e IM |
1258 | struct stack_trace trace; |
1259 | ||
e77405ad | 1260 | event = trace_buffer_lock_reserve(buffer, TRACE_STACK, |
51a763dd | 1261 | sizeof(*entry), flags, pc); |
3928a8a2 SR |
1262 | if (!event) |
1263 | return; | |
1264 | entry = ring_buffer_event_data(event); | |
777e208d | 1265 | memset(&entry->caller, 0, sizeof(entry->caller)); |
86387f7e IM |
1266 | |
1267 | trace.nr_entries = 0; | |
1268 | trace.max_entries = FTRACE_STACK_ENTRIES; | |
1269 | trace.skip = skip; | |
777e208d | 1270 | trace.entries = entry->caller; |
86387f7e | 1271 | |
1fd8df2c MH |
1272 | if (regs) |
1273 | save_stack_trace_regs(regs, &trace); | |
1274 | else | |
1275 | save_stack_trace(&trace); | |
e77405ad SR |
1276 | if (!filter_check_discard(call, entry, buffer, event)) |
1277 | ring_buffer_unlock_commit(buffer, event); | |
f0a920d5 IM |
1278 | } |
1279 | ||
1fd8df2c MH |
1280 | void ftrace_trace_stack_regs(struct ring_buffer *buffer, unsigned long flags, |
1281 | int skip, int pc, struct pt_regs *regs) | |
1282 | { | |
1283 | if (!(trace_flags & TRACE_ITER_STACKTRACE)) | |
1284 | return; | |
1285 | ||
1286 | __ftrace_trace_stack(buffer, flags, skip, pc, regs); | |
1287 | } | |
1288 | ||
e77405ad SR |
1289 | void ftrace_trace_stack(struct ring_buffer *buffer, unsigned long flags, |
1290 | int skip, int pc) | |
53614991 SR |
1291 | { |
1292 | if (!(trace_flags & TRACE_ITER_STACKTRACE)) | |
1293 | return; | |
1294 | ||
1fd8df2c | 1295 | __ftrace_trace_stack(buffer, flags, skip, pc, NULL); |
53614991 SR |
1296 | } |
1297 | ||
c0a0d0d3 FW |
1298 | void __trace_stack(struct trace_array *tr, unsigned long flags, int skip, |
1299 | int pc) | |
38697053 | 1300 | { |
1fd8df2c | 1301 | __ftrace_trace_stack(tr->buffer, flags, skip, pc, NULL); |
38697053 SR |
1302 | } |
1303 | ||
03889384 SR |
1304 | /** |
1305 | * trace_dump_stack - record a stack back trace in the trace buffer | |
1306 | */ | |
1307 | void trace_dump_stack(void) | |
1308 | { | |
1309 | unsigned long flags; | |
1310 | ||
1311 | if (tracing_disabled || tracing_selftest_running) | |
e36c5458 | 1312 | return; |
03889384 SR |
1313 | |
1314 | local_save_flags(flags); | |
1315 | ||
1316 | /* skipping 3 traces, seems to get us at the caller of this function */ | |
1fd8df2c | 1317 | __ftrace_trace_stack(global_trace.buffer, flags, 3, preempt_count(), NULL); |
03889384 SR |
1318 | } |
1319 | ||
91e86e56 SR |
1320 | static DEFINE_PER_CPU(int, user_stack_count); |
1321 | ||
e77405ad SR |
1322 | void |
1323 | ftrace_trace_userstack(struct ring_buffer *buffer, unsigned long flags, int pc) | |
02b67518 | 1324 | { |
e1112b4d | 1325 | struct ftrace_event_call *call = &event_user_stack; |
8d7c6a96 | 1326 | struct ring_buffer_event *event; |
02b67518 TE |
1327 | struct userstack_entry *entry; |
1328 | struct stack_trace trace; | |
02b67518 TE |
1329 | |
1330 | if (!(trace_flags & TRACE_ITER_USERSTACKTRACE)) | |
1331 | return; | |
1332 | ||
b6345879 SR |
1333 | /* |
1334 | * NMIs can not handle page faults, even with fix ups. | |
1335 | * The save user stack can (and often does) fault. | |
1336 | */ | |
1337 | if (unlikely(in_nmi())) | |
1338 | return; | |
02b67518 | 1339 | |
91e86e56 SR |
1340 | /* |
1341 | * prevent recursion, since the user stack tracing may | |
1342 | * trigger other kernel events. | |
1343 | */ | |
1344 | preempt_disable(); | |
1345 | if (__this_cpu_read(user_stack_count)) | |
1346 | goto out; | |
1347 | ||
1348 | __this_cpu_inc(user_stack_count); | |
1349 | ||
e77405ad | 1350 | event = trace_buffer_lock_reserve(buffer, TRACE_USER_STACK, |
51a763dd | 1351 | sizeof(*entry), flags, pc); |
02b67518 | 1352 | if (!event) |
1dbd1951 | 1353 | goto out_drop_count; |
02b67518 | 1354 | entry = ring_buffer_event_data(event); |
02b67518 | 1355 | |
48659d31 | 1356 | entry->tgid = current->tgid; |
02b67518 TE |
1357 | memset(&entry->caller, 0, sizeof(entry->caller)); |
1358 | ||
1359 | trace.nr_entries = 0; | |
1360 | trace.max_entries = FTRACE_STACK_ENTRIES; | |
1361 | trace.skip = 0; | |
1362 | trace.entries = entry->caller; | |
1363 | ||
1364 | save_stack_trace_user(&trace); | |
e77405ad SR |
1365 | if (!filter_check_discard(call, entry, buffer, event)) |
1366 | ring_buffer_unlock_commit(buffer, event); | |
91e86e56 | 1367 | |
1dbd1951 | 1368 | out_drop_count: |
91e86e56 | 1369 | __this_cpu_dec(user_stack_count); |
91e86e56 SR |
1370 | out: |
1371 | preempt_enable(); | |
02b67518 TE |
1372 | } |
1373 | ||
4fd27358 HE |
1374 | #ifdef UNUSED |
1375 | static void __trace_userstack(struct trace_array *tr, unsigned long flags) | |
02b67518 | 1376 | { |
7be42151 | 1377 | ftrace_trace_userstack(tr, flags, preempt_count()); |
02b67518 | 1378 | } |
4fd27358 | 1379 | #endif /* UNUSED */ |
02b67518 | 1380 | |
c0a0d0d3 FW |
1381 | #endif /* CONFIG_STACKTRACE */ |
1382 | ||
769b0441 | 1383 | /** |
48ead020 | 1384 | * trace_vbprintk - write binary msg to tracing buffer |
769b0441 FW |
1385 | * |
1386 | */ | |
40ce74f1 | 1387 | int trace_vbprintk(unsigned long ip, const char *fmt, va_list args) |
769b0441 | 1388 | { |
445c8951 | 1389 | static arch_spinlock_t trace_buf_lock = |
edc35bd7 | 1390 | (arch_spinlock_t)__ARCH_SPIN_LOCK_UNLOCKED; |
769b0441 FW |
1391 | static u32 trace_buf[TRACE_BUF_SIZE]; |
1392 | ||
e1112b4d | 1393 | struct ftrace_event_call *call = &event_bprint; |
769b0441 | 1394 | struct ring_buffer_event *event; |
e77405ad | 1395 | struct ring_buffer *buffer; |
769b0441 FW |
1396 | struct trace_array *tr = &global_trace; |
1397 | struct trace_array_cpu *data; | |
48ead020 | 1398 | struct bprint_entry *entry; |
769b0441 | 1399 | unsigned long flags; |
3189cdb3 | 1400 | int disable; |
769b0441 FW |
1401 | int cpu, len = 0, size, pc; |
1402 | ||
1403 | if (unlikely(tracing_selftest_running || tracing_disabled)) | |
1404 | return 0; | |
1405 | ||
1406 | /* Don't pollute graph traces with trace_vprintk internals */ | |
1407 | pause_graph_tracing(); | |
1408 | ||
1409 | pc = preempt_count(); | |
5168ae50 | 1410 | preempt_disable_notrace(); |
769b0441 FW |
1411 | cpu = raw_smp_processor_id(); |
1412 | data = tr->data[cpu]; | |
1413 | ||
3189cdb3 SR |
1414 | disable = atomic_inc_return(&data->disabled); |
1415 | if (unlikely(disable != 1)) | |
769b0441 FW |
1416 | goto out; |
1417 | ||
80370cb7 SR |
1418 | /* Lockdep uses trace_printk for lock tracing */ |
1419 | local_irq_save(flags); | |
0199c4e6 | 1420 | arch_spin_lock(&trace_buf_lock); |
769b0441 FW |
1421 | len = vbin_printf(trace_buf, TRACE_BUF_SIZE, fmt, args); |
1422 | ||
1423 | if (len > TRACE_BUF_SIZE || len < 0) | |
1424 | goto out_unlock; | |
1425 | ||
1426 | size = sizeof(*entry) + sizeof(u32) * len; | |
e77405ad SR |
1427 | buffer = tr->buffer; |
1428 | event = trace_buffer_lock_reserve(buffer, TRACE_BPRINT, size, | |
1429 | flags, pc); | |
769b0441 FW |
1430 | if (!event) |
1431 | goto out_unlock; | |
1432 | entry = ring_buffer_event_data(event); | |
1433 | entry->ip = ip; | |
769b0441 FW |
1434 | entry->fmt = fmt; |
1435 | ||
1436 | memcpy(entry->buf, trace_buf, sizeof(u32) * len); | |
d931369b | 1437 | if (!filter_check_discard(call, entry, buffer, event)) { |
e77405ad | 1438 | ring_buffer_unlock_commit(buffer, event); |
d931369b SR |
1439 | ftrace_trace_stack(buffer, flags, 6, pc); |
1440 | } | |
769b0441 FW |
1441 | |
1442 | out_unlock: | |
0199c4e6 | 1443 | arch_spin_unlock(&trace_buf_lock); |
80370cb7 | 1444 | local_irq_restore(flags); |
769b0441 FW |
1445 | |
1446 | out: | |
3189cdb3 | 1447 | atomic_dec_return(&data->disabled); |
5168ae50 | 1448 | preempt_enable_notrace(); |
769b0441 FW |
1449 | unpause_graph_tracing(); |
1450 | ||
1451 | return len; | |
1452 | } | |
48ead020 FW |
1453 | EXPORT_SYMBOL_GPL(trace_vbprintk); |
1454 | ||
659372d3 SR |
1455 | int trace_array_printk(struct trace_array *tr, |
1456 | unsigned long ip, const char *fmt, ...) | |
1457 | { | |
1458 | int ret; | |
1459 | va_list ap; | |
1460 | ||
1461 | if (!(trace_flags & TRACE_ITER_PRINTK)) | |
1462 | return 0; | |
1463 | ||
1464 | va_start(ap, fmt); | |
1465 | ret = trace_array_vprintk(tr, ip, fmt, ap); | |
1466 | va_end(ap); | |
1467 | return ret; | |
1468 | } | |
1469 | ||
1470 | int trace_array_vprintk(struct trace_array *tr, | |
1471 | unsigned long ip, const char *fmt, va_list args) | |
48ead020 | 1472 | { |
edc35bd7 | 1473 | static arch_spinlock_t trace_buf_lock = __ARCH_SPIN_LOCK_UNLOCKED; |
48ead020 FW |
1474 | static char trace_buf[TRACE_BUF_SIZE]; |
1475 | ||
e1112b4d | 1476 | struct ftrace_event_call *call = &event_print; |
48ead020 | 1477 | struct ring_buffer_event *event; |
e77405ad | 1478 | struct ring_buffer *buffer; |
48ead020 FW |
1479 | struct trace_array_cpu *data; |
1480 | int cpu, len = 0, size, pc; | |
1481 | struct print_entry *entry; | |
1482 | unsigned long irq_flags; | |
3189cdb3 | 1483 | int disable; |
48ead020 FW |
1484 | |
1485 | if (tracing_disabled || tracing_selftest_running) | |
1486 | return 0; | |
1487 | ||
1488 | pc = preempt_count(); | |
1489 | preempt_disable_notrace(); | |
1490 | cpu = raw_smp_processor_id(); | |
1491 | data = tr->data[cpu]; | |
1492 | ||
3189cdb3 SR |
1493 | disable = atomic_inc_return(&data->disabled); |
1494 | if (unlikely(disable != 1)) | |
48ead020 FW |
1495 | goto out; |
1496 | ||
1497 | pause_graph_tracing(); | |
1498 | raw_local_irq_save(irq_flags); | |
0199c4e6 | 1499 | arch_spin_lock(&trace_buf_lock); |
f2942487 | 1500 | len = vsnprintf(trace_buf, TRACE_BUF_SIZE, fmt, args); |
48ead020 FW |
1501 | |
1502 | size = sizeof(*entry) + len + 1; | |
e77405ad SR |
1503 | buffer = tr->buffer; |
1504 | event = trace_buffer_lock_reserve(buffer, TRACE_PRINT, size, | |
1505 | irq_flags, pc); | |
48ead020 FW |
1506 | if (!event) |
1507 | goto out_unlock; | |
1508 | entry = ring_buffer_event_data(event); | |
c13d2f7c | 1509 | entry->ip = ip; |
48ead020 FW |
1510 | |
1511 | memcpy(&entry->buf, trace_buf, len); | |
c13d2f7c | 1512 | entry->buf[len] = '\0'; |
d931369b | 1513 | if (!filter_check_discard(call, entry, buffer, event)) { |
e77405ad | 1514 | ring_buffer_unlock_commit(buffer, event); |
d931369b SR |
1515 | ftrace_trace_stack(buffer, irq_flags, 6, pc); |
1516 | } | |
48ead020 FW |
1517 | |
1518 | out_unlock: | |
0199c4e6 | 1519 | arch_spin_unlock(&trace_buf_lock); |
48ead020 FW |
1520 | raw_local_irq_restore(irq_flags); |
1521 | unpause_graph_tracing(); | |
1522 | out: | |
3189cdb3 | 1523 | atomic_dec_return(&data->disabled); |
48ead020 FW |
1524 | preempt_enable_notrace(); |
1525 | ||
1526 | return len; | |
1527 | } | |
659372d3 SR |
1528 | |
1529 | int trace_vprintk(unsigned long ip, const char *fmt, va_list args) | |
1530 | { | |
a813a159 | 1531 | return trace_array_vprintk(&global_trace, ip, fmt, args); |
659372d3 | 1532 | } |
769b0441 FW |
1533 | EXPORT_SYMBOL_GPL(trace_vprintk); |
1534 | ||
e2ac8ef5 | 1535 | static void trace_iterator_increment(struct trace_iterator *iter) |
5a90f577 | 1536 | { |
d769041f SR |
1537 | /* Don't allow ftrace to trace into the ring buffers */ |
1538 | ftrace_disable_cpu(); | |
1539 | ||
5a90f577 | 1540 | iter->idx++; |
d769041f SR |
1541 | if (iter->buffer_iter[iter->cpu]) |
1542 | ring_buffer_read(iter->buffer_iter[iter->cpu], NULL); | |
1543 | ||
1544 | ftrace_enable_cpu(); | |
5a90f577 SR |
1545 | } |
1546 | ||
e309b41d | 1547 | static struct trace_entry * |
bc21b478 SR |
1548 | peek_next_entry(struct trace_iterator *iter, int cpu, u64 *ts, |
1549 | unsigned long *lost_events) | |
dd0e545f | 1550 | { |
3928a8a2 SR |
1551 | struct ring_buffer_event *event; |
1552 | struct ring_buffer_iter *buf_iter = iter->buffer_iter[cpu]; | |
dd0e545f | 1553 | |
d769041f SR |
1554 | /* Don't allow ftrace to trace into the ring buffers */ |
1555 | ftrace_disable_cpu(); | |
1556 | ||
1557 | if (buf_iter) | |
1558 | event = ring_buffer_iter_peek(buf_iter, ts); | |
1559 | else | |
bc21b478 SR |
1560 | event = ring_buffer_peek(iter->tr->buffer, cpu, ts, |
1561 | lost_events); | |
d769041f SR |
1562 | |
1563 | ftrace_enable_cpu(); | |
1564 | ||
3928a8a2 | 1565 | return event ? ring_buffer_event_data(event) : NULL; |
dd0e545f | 1566 | } |
d769041f | 1567 | |
dd0e545f | 1568 | static struct trace_entry * |
bc21b478 SR |
1569 | __find_next_entry(struct trace_iterator *iter, int *ent_cpu, |
1570 | unsigned long *missing_events, u64 *ent_ts) | |
bc0c38d1 | 1571 | { |
3928a8a2 | 1572 | struct ring_buffer *buffer = iter->tr->buffer; |
bc0c38d1 | 1573 | struct trace_entry *ent, *next = NULL; |
aa27497c | 1574 | unsigned long lost_events = 0, next_lost = 0; |
b04cc6b1 | 1575 | int cpu_file = iter->cpu_file; |
3928a8a2 | 1576 | u64 next_ts = 0, ts; |
bc0c38d1 SR |
1577 | int next_cpu = -1; |
1578 | int cpu; | |
1579 | ||
b04cc6b1 FW |
1580 | /* |
1581 | * If we are in a per_cpu trace file, don't bother by iterating over | |
1582 | * all cpu and peek directly. | |
1583 | */ | |
1584 | if (cpu_file > TRACE_PIPE_ALL_CPU) { | |
1585 | if (ring_buffer_empty_cpu(buffer, cpu_file)) | |
1586 | return NULL; | |
bc21b478 | 1587 | ent = peek_next_entry(iter, cpu_file, ent_ts, missing_events); |
b04cc6b1 FW |
1588 | if (ent_cpu) |
1589 | *ent_cpu = cpu_file; | |
1590 | ||
1591 | return ent; | |
1592 | } | |
1593 | ||
ab46428c | 1594 | for_each_tracing_cpu(cpu) { |
dd0e545f | 1595 | |
3928a8a2 SR |
1596 | if (ring_buffer_empty_cpu(buffer, cpu)) |
1597 | continue; | |
dd0e545f | 1598 | |
bc21b478 | 1599 | ent = peek_next_entry(iter, cpu, &ts, &lost_events); |
dd0e545f | 1600 | |
cdd31cd2 IM |
1601 | /* |
1602 | * Pick the entry with the smallest timestamp: | |
1603 | */ | |
3928a8a2 | 1604 | if (ent && (!next || ts < next_ts)) { |
bc0c38d1 SR |
1605 | next = ent; |
1606 | next_cpu = cpu; | |
3928a8a2 | 1607 | next_ts = ts; |
bc21b478 | 1608 | next_lost = lost_events; |
bc0c38d1 SR |
1609 | } |
1610 | } | |
1611 | ||
1612 | if (ent_cpu) | |
1613 | *ent_cpu = next_cpu; | |
1614 | ||
3928a8a2 SR |
1615 | if (ent_ts) |
1616 | *ent_ts = next_ts; | |
1617 | ||
bc21b478 SR |
1618 | if (missing_events) |
1619 | *missing_events = next_lost; | |
1620 | ||
bc0c38d1 SR |
1621 | return next; |
1622 | } | |
1623 | ||
dd0e545f | 1624 | /* Find the next real entry, without updating the iterator itself */ |
c4a8e8be FW |
1625 | struct trace_entry *trace_find_next_entry(struct trace_iterator *iter, |
1626 | int *ent_cpu, u64 *ent_ts) | |
bc0c38d1 | 1627 | { |
bc21b478 | 1628 | return __find_next_entry(iter, ent_cpu, NULL, ent_ts); |
dd0e545f SR |
1629 | } |
1630 | ||
1631 | /* Find the next real entry, and increment the iterator to the next entry */ | |
955b61e5 | 1632 | void *trace_find_next_entry_inc(struct trace_iterator *iter) |
dd0e545f | 1633 | { |
bc21b478 SR |
1634 | iter->ent = __find_next_entry(iter, &iter->cpu, |
1635 | &iter->lost_events, &iter->ts); | |
dd0e545f | 1636 | |
3928a8a2 | 1637 | if (iter->ent) |
e2ac8ef5 | 1638 | trace_iterator_increment(iter); |
dd0e545f | 1639 | |
3928a8a2 | 1640 | return iter->ent ? iter : NULL; |
b3806b43 | 1641 | } |
bc0c38d1 | 1642 | |
e309b41d | 1643 | static void trace_consume(struct trace_iterator *iter) |
b3806b43 | 1644 | { |
d769041f SR |
1645 | /* Don't allow ftrace to trace into the ring buffers */ |
1646 | ftrace_disable_cpu(); | |
bc21b478 SR |
1647 | ring_buffer_consume(iter->tr->buffer, iter->cpu, &iter->ts, |
1648 | &iter->lost_events); | |
d769041f | 1649 | ftrace_enable_cpu(); |
bc0c38d1 SR |
1650 | } |
1651 | ||
e309b41d | 1652 | static void *s_next(struct seq_file *m, void *v, loff_t *pos) |
bc0c38d1 SR |
1653 | { |
1654 | struct trace_iterator *iter = m->private; | |
bc0c38d1 | 1655 | int i = (int)*pos; |
4e3c3333 | 1656 | void *ent; |
bc0c38d1 | 1657 | |
a63ce5b3 SR |
1658 | WARN_ON_ONCE(iter->leftover); |
1659 | ||
bc0c38d1 SR |
1660 | (*pos)++; |
1661 | ||
1662 | /* can't go backwards */ | |
1663 | if (iter->idx > i) | |
1664 | return NULL; | |
1665 | ||
1666 | if (iter->idx < 0) | |
955b61e5 | 1667 | ent = trace_find_next_entry_inc(iter); |
bc0c38d1 SR |
1668 | else |
1669 | ent = iter; | |
1670 | ||
1671 | while (ent && iter->idx < i) | |
955b61e5 | 1672 | ent = trace_find_next_entry_inc(iter); |
bc0c38d1 SR |
1673 | |
1674 | iter->pos = *pos; | |
1675 | ||
bc0c38d1 SR |
1676 | return ent; |
1677 | } | |
1678 | ||
955b61e5 | 1679 | void tracing_iter_reset(struct trace_iterator *iter, int cpu) |
2f26ebd5 SR |
1680 | { |
1681 | struct trace_array *tr = iter->tr; | |
1682 | struct ring_buffer_event *event; | |
1683 | struct ring_buffer_iter *buf_iter; | |
1684 | unsigned long entries = 0; | |
1685 | u64 ts; | |
1686 | ||
1687 | tr->data[cpu]->skipped_entries = 0; | |
1688 | ||
1689 | if (!iter->buffer_iter[cpu]) | |
1690 | return; | |
1691 | ||
1692 | buf_iter = iter->buffer_iter[cpu]; | |
1693 | ring_buffer_iter_reset(buf_iter); | |
1694 | ||
1695 | /* | |
1696 | * We could have the case with the max latency tracers | |
1697 | * that a reset never took place on a cpu. This is evident | |
1698 | * by the timestamp being before the start of the buffer. | |
1699 | */ | |
1700 | while ((event = ring_buffer_iter_peek(buf_iter, &ts))) { | |
1701 | if (ts >= iter->tr->time_start) | |
1702 | break; | |
1703 | entries++; | |
1704 | ring_buffer_read(buf_iter, NULL); | |
1705 | } | |
1706 | ||
1707 | tr->data[cpu]->skipped_entries = entries; | |
1708 | } | |
1709 | ||
d7350c3f | 1710 | /* |
d7350c3f FW |
1711 | * The current tracer is copied to avoid a global locking |
1712 | * all around. | |
1713 | */ | |
bc0c38d1 SR |
1714 | static void *s_start(struct seq_file *m, loff_t *pos) |
1715 | { | |
1716 | struct trace_iterator *iter = m->private; | |
d7350c3f | 1717 | static struct tracer *old_tracer; |
b04cc6b1 | 1718 | int cpu_file = iter->cpu_file; |
bc0c38d1 SR |
1719 | void *p = NULL; |
1720 | loff_t l = 0; | |
3928a8a2 | 1721 | int cpu; |
bc0c38d1 | 1722 | |
d7350c3f | 1723 | /* copy the tracer to avoid using a global lock all around */ |
bc0c38d1 | 1724 | mutex_lock(&trace_types_lock); |
d7350c3f FW |
1725 | if (unlikely(old_tracer != current_trace && current_trace)) { |
1726 | old_tracer = current_trace; | |
1727 | *iter->trace = *current_trace; | |
d15f57f2 | 1728 | } |
d7350c3f | 1729 | mutex_unlock(&trace_types_lock); |
bc0c38d1 SR |
1730 | |
1731 | atomic_inc(&trace_record_cmdline_disabled); | |
1732 | ||
bc0c38d1 SR |
1733 | if (*pos != iter->pos) { |
1734 | iter->ent = NULL; | |
1735 | iter->cpu = 0; | |
1736 | iter->idx = -1; | |
1737 | ||
d769041f SR |
1738 | ftrace_disable_cpu(); |
1739 | ||
b04cc6b1 FW |
1740 | if (cpu_file == TRACE_PIPE_ALL_CPU) { |
1741 | for_each_tracing_cpu(cpu) | |
2f26ebd5 | 1742 | tracing_iter_reset(iter, cpu); |
b04cc6b1 | 1743 | } else |
2f26ebd5 | 1744 | tracing_iter_reset(iter, cpu_file); |
bc0c38d1 | 1745 | |
d769041f SR |
1746 | ftrace_enable_cpu(); |
1747 | ||
ac91d854 | 1748 | iter->leftover = 0; |
bc0c38d1 SR |
1749 | for (p = iter; p && l < *pos; p = s_next(m, p, &l)) |
1750 | ; | |
1751 | ||
1752 | } else { | |
a63ce5b3 SR |
1753 | /* |
1754 | * If we overflowed the seq_file before, then we want | |
1755 | * to just reuse the trace_seq buffer again. | |
1756 | */ | |
1757 | if (iter->leftover) | |
1758 | p = iter; | |
1759 | else { | |
1760 | l = *pos - 1; | |
1761 | p = s_next(m, p, &l); | |
1762 | } | |
bc0c38d1 SR |
1763 | } |
1764 | ||
4f535968 | 1765 | trace_event_read_lock(); |
7e53bd42 | 1766 | trace_access_lock(cpu_file); |
bc0c38d1 SR |
1767 | return p; |
1768 | } | |
1769 | ||
1770 | static void s_stop(struct seq_file *m, void *p) | |
1771 | { | |
7e53bd42 LJ |
1772 | struct trace_iterator *iter = m->private; |
1773 | ||
bc0c38d1 | 1774 | atomic_dec(&trace_record_cmdline_disabled); |
7e53bd42 | 1775 | trace_access_unlock(iter->cpu_file); |
4f535968 | 1776 | trace_event_read_unlock(); |
bc0c38d1 SR |
1777 | } |
1778 | ||
e309b41d | 1779 | static void print_lat_help_header(struct seq_file *m) |
bc0c38d1 | 1780 | { |
a6168353 ME |
1781 | seq_puts(m, "# _------=> CPU# \n"); |
1782 | seq_puts(m, "# / _-----=> irqs-off \n"); | |
1783 | seq_puts(m, "# | / _----=> need-resched \n"); | |
1784 | seq_puts(m, "# || / _---=> hardirq/softirq \n"); | |
1785 | seq_puts(m, "# ||| / _--=> preempt-depth \n"); | |
e6e1e259 SR |
1786 | seq_puts(m, "# |||| / delay \n"); |
1787 | seq_puts(m, "# cmd pid ||||| time | caller \n"); | |
1788 | seq_puts(m, "# \\ / ||||| \\ | / \n"); | |
bc0c38d1 SR |
1789 | } |
1790 | ||
e309b41d | 1791 | static void print_func_help_header(struct seq_file *m) |
bc0c38d1 | 1792 | { |
a6168353 ME |
1793 | seq_puts(m, "# TASK-PID CPU# TIMESTAMP FUNCTION\n"); |
1794 | seq_puts(m, "# | | | | |\n"); | |
bc0c38d1 SR |
1795 | } |
1796 | ||
1797 | ||
62b915f1 | 1798 | void |
bc0c38d1 SR |
1799 | print_trace_header(struct seq_file *m, struct trace_iterator *iter) |
1800 | { | |
1801 | unsigned long sym_flags = (trace_flags & TRACE_ITER_SYM_MASK); | |
1802 | struct trace_array *tr = iter->tr; | |
1803 | struct trace_array_cpu *data = tr->data[tr->cpu]; | |
1804 | struct tracer *type = current_trace; | |
2f26ebd5 SR |
1805 | unsigned long entries = 0; |
1806 | unsigned long total = 0; | |
1807 | unsigned long count; | |
bc0c38d1 | 1808 | const char *name = "preemption"; |
2f26ebd5 | 1809 | int cpu; |
bc0c38d1 SR |
1810 | |
1811 | if (type) | |
1812 | name = type->name; | |
1813 | ||
2f26ebd5 SR |
1814 | |
1815 | for_each_tracing_cpu(cpu) { | |
1816 | count = ring_buffer_entries_cpu(tr->buffer, cpu); | |
1817 | /* | |
1818 | * If this buffer has skipped entries, then we hold all | |
1819 | * entries for the trace and we need to ignore the | |
1820 | * ones before the time stamp. | |
1821 | */ | |
1822 | if (tr->data[cpu]->skipped_entries) { | |
1823 | count -= tr->data[cpu]->skipped_entries; | |
1824 | /* total is the same as the entries */ | |
1825 | total += count; | |
1826 | } else | |
1827 | total += count + | |
1828 | ring_buffer_overrun_cpu(tr->buffer, cpu); | |
1829 | entries += count; | |
1830 | } | |
bc0c38d1 | 1831 | |
888b55dc | 1832 | seq_printf(m, "# %s latency trace v1.1.5 on %s\n", |
bc0c38d1 | 1833 | name, UTS_RELEASE); |
888b55dc | 1834 | seq_puts(m, "# -----------------------------------" |
bc0c38d1 | 1835 | "---------------------------------\n"); |
888b55dc | 1836 | seq_printf(m, "# latency: %lu us, #%lu/%lu, CPU#%d |" |
bc0c38d1 | 1837 | " (M:%s VP:%d, KP:%d, SP:%d HP:%d", |
57f50be1 | 1838 | nsecs_to_usecs(data->saved_latency), |
bc0c38d1 | 1839 | entries, |
4c11d7ae | 1840 | total, |
bc0c38d1 SR |
1841 | tr->cpu, |
1842 | #if defined(CONFIG_PREEMPT_NONE) | |
1843 | "server", | |
1844 | #elif defined(CONFIG_PREEMPT_VOLUNTARY) | |
1845 | "desktop", | |
b5c21b45 | 1846 | #elif defined(CONFIG_PREEMPT) |
bc0c38d1 SR |
1847 | "preempt", |
1848 | #else | |
1849 | "unknown", | |
1850 | #endif | |
1851 | /* These are reserved for later use */ | |
1852 | 0, 0, 0, 0); | |
1853 | #ifdef CONFIG_SMP | |
1854 | seq_printf(m, " #P:%d)\n", num_online_cpus()); | |
1855 | #else | |
1856 | seq_puts(m, ")\n"); | |
1857 | #endif | |
888b55dc KM |
1858 | seq_puts(m, "# -----------------\n"); |
1859 | seq_printf(m, "# | task: %.16s-%d " | |
bc0c38d1 SR |
1860 | "(uid:%d nice:%ld policy:%ld rt_prio:%ld)\n", |
1861 | data->comm, data->pid, data->uid, data->nice, | |
1862 | data->policy, data->rt_priority); | |
888b55dc | 1863 | seq_puts(m, "# -----------------\n"); |
bc0c38d1 SR |
1864 | |
1865 | if (data->critical_start) { | |
888b55dc | 1866 | seq_puts(m, "# => started at: "); |
214023c3 SR |
1867 | seq_print_ip_sym(&iter->seq, data->critical_start, sym_flags); |
1868 | trace_print_seq(m, &iter->seq); | |
888b55dc | 1869 | seq_puts(m, "\n# => ended at: "); |
214023c3 SR |
1870 | seq_print_ip_sym(&iter->seq, data->critical_end, sym_flags); |
1871 | trace_print_seq(m, &iter->seq); | |
8248ac05 | 1872 | seq_puts(m, "\n#\n"); |
bc0c38d1 SR |
1873 | } |
1874 | ||
888b55dc | 1875 | seq_puts(m, "#\n"); |
bc0c38d1 SR |
1876 | } |
1877 | ||
a309720c SR |
1878 | static void test_cpu_buff_start(struct trace_iterator *iter) |
1879 | { | |
1880 | struct trace_seq *s = &iter->seq; | |
1881 | ||
12ef7d44 SR |
1882 | if (!(trace_flags & TRACE_ITER_ANNOTATE)) |
1883 | return; | |
1884 | ||
1885 | if (!(iter->iter_flags & TRACE_FILE_ANNOTATE)) | |
1886 | return; | |
1887 | ||
4462344e | 1888 | if (cpumask_test_cpu(iter->cpu, iter->started)) |
a309720c SR |
1889 | return; |
1890 | ||
2f26ebd5 SR |
1891 | if (iter->tr->data[iter->cpu]->skipped_entries) |
1892 | return; | |
1893 | ||
4462344e | 1894 | cpumask_set_cpu(iter->cpu, iter->started); |
b0dfa978 FW |
1895 | |
1896 | /* Don't print started cpu buffer for the first entry of the trace */ | |
1897 | if (iter->idx > 1) | |
1898 | trace_seq_printf(s, "##### CPU %u buffer started ####\n", | |
1899 | iter->cpu); | |
a309720c SR |
1900 | } |
1901 | ||
2c4f035f | 1902 | static enum print_line_t print_trace_fmt(struct trace_iterator *iter) |
bc0c38d1 | 1903 | { |
214023c3 | 1904 | struct trace_seq *s = &iter->seq; |
bc0c38d1 | 1905 | unsigned long sym_flags = (trace_flags & TRACE_ITER_SYM_MASK); |
4e3c3333 | 1906 | struct trace_entry *entry; |
f633cef0 | 1907 | struct trace_event *event; |
bc0c38d1 | 1908 | |
4e3c3333 | 1909 | entry = iter->ent; |
dd0e545f | 1910 | |
a309720c SR |
1911 | test_cpu_buff_start(iter); |
1912 | ||
c4a8e8be | 1913 | event = ftrace_find_event(entry->type); |
bc0c38d1 | 1914 | |
c4a8e8be | 1915 | if (trace_flags & TRACE_ITER_CONTEXT_INFO) { |
27d48be8 SR |
1916 | if (iter->iter_flags & TRACE_FILE_LAT_FMT) { |
1917 | if (!trace_print_lat_context(iter)) | |
1918 | goto partial; | |
1919 | } else { | |
1920 | if (!trace_print_context(iter)) | |
1921 | goto partial; | |
1922 | } | |
c4a8e8be | 1923 | } |
bc0c38d1 | 1924 | |
268ccda0 | 1925 | if (event) |
a9a57763 | 1926 | return event->funcs->trace(iter, sym_flags, event); |
d9793bd8 ACM |
1927 | |
1928 | if (!trace_seq_printf(s, "Unknown type %d\n", entry->type)) | |
1929 | goto partial; | |
02b67518 | 1930 | |
2c4f035f | 1931 | return TRACE_TYPE_HANDLED; |
d9793bd8 ACM |
1932 | partial: |
1933 | return TRACE_TYPE_PARTIAL_LINE; | |
bc0c38d1 SR |
1934 | } |
1935 | ||
2c4f035f | 1936 | static enum print_line_t print_raw_fmt(struct trace_iterator *iter) |
f9896bf3 IM |
1937 | { |
1938 | struct trace_seq *s = &iter->seq; | |
1939 | struct trace_entry *entry; | |
f633cef0 | 1940 | struct trace_event *event; |
f9896bf3 IM |
1941 | |
1942 | entry = iter->ent; | |
dd0e545f | 1943 | |
c4a8e8be | 1944 | if (trace_flags & TRACE_ITER_CONTEXT_INFO) { |
d9793bd8 ACM |
1945 | if (!trace_seq_printf(s, "%d %d %llu ", |
1946 | entry->pid, iter->cpu, iter->ts)) | |
1947 | goto partial; | |
c4a8e8be | 1948 | } |
f9896bf3 | 1949 | |
f633cef0 | 1950 | event = ftrace_find_event(entry->type); |
268ccda0 | 1951 | if (event) |
a9a57763 | 1952 | return event->funcs->raw(iter, 0, event); |
d9793bd8 ACM |
1953 | |
1954 | if (!trace_seq_printf(s, "%d ?\n", entry->type)) | |
1955 | goto partial; | |
777e208d | 1956 | |
2c4f035f | 1957 | return TRACE_TYPE_HANDLED; |
d9793bd8 ACM |
1958 | partial: |
1959 | return TRACE_TYPE_PARTIAL_LINE; | |
f9896bf3 IM |
1960 | } |
1961 | ||
2c4f035f | 1962 | static enum print_line_t print_hex_fmt(struct trace_iterator *iter) |
5e3ca0ec IM |
1963 | { |
1964 | struct trace_seq *s = &iter->seq; | |
1965 | unsigned char newline = '\n'; | |
1966 | struct trace_entry *entry; | |
f633cef0 | 1967 | struct trace_event *event; |
5e3ca0ec IM |
1968 | |
1969 | entry = iter->ent; | |
dd0e545f | 1970 | |
c4a8e8be FW |
1971 | if (trace_flags & TRACE_ITER_CONTEXT_INFO) { |
1972 | SEQ_PUT_HEX_FIELD_RET(s, entry->pid); | |
1973 | SEQ_PUT_HEX_FIELD_RET(s, iter->cpu); | |
1974 | SEQ_PUT_HEX_FIELD_RET(s, iter->ts); | |
1975 | } | |
5e3ca0ec | 1976 | |
f633cef0 | 1977 | event = ftrace_find_event(entry->type); |
268ccda0 | 1978 | if (event) { |
a9a57763 | 1979 | enum print_line_t ret = event->funcs->hex(iter, 0, event); |
d9793bd8 ACM |
1980 | if (ret != TRACE_TYPE_HANDLED) |
1981 | return ret; | |
1982 | } | |
7104f300 | 1983 | |
5e3ca0ec IM |
1984 | SEQ_PUT_FIELD_RET(s, newline); |
1985 | ||
2c4f035f | 1986 | return TRACE_TYPE_HANDLED; |
5e3ca0ec IM |
1987 | } |
1988 | ||
2c4f035f | 1989 | static enum print_line_t print_bin_fmt(struct trace_iterator *iter) |
cb0f12aa IM |
1990 | { |
1991 | struct trace_seq *s = &iter->seq; | |
1992 | struct trace_entry *entry; | |
f633cef0 | 1993 | struct trace_event *event; |
cb0f12aa IM |
1994 | |
1995 | entry = iter->ent; | |
dd0e545f | 1996 | |
c4a8e8be FW |
1997 | if (trace_flags & TRACE_ITER_CONTEXT_INFO) { |
1998 | SEQ_PUT_FIELD_RET(s, entry->pid); | |
1830b52d | 1999 | SEQ_PUT_FIELD_RET(s, iter->cpu); |
c4a8e8be FW |
2000 | SEQ_PUT_FIELD_RET(s, iter->ts); |
2001 | } | |
cb0f12aa | 2002 | |
f633cef0 | 2003 | event = ftrace_find_event(entry->type); |
a9a57763 SR |
2004 | return event ? event->funcs->binary(iter, 0, event) : |
2005 | TRACE_TYPE_HANDLED; | |
cb0f12aa IM |
2006 | } |
2007 | ||
62b915f1 | 2008 | int trace_empty(struct trace_iterator *iter) |
bc0c38d1 | 2009 | { |
bc0c38d1 SR |
2010 | int cpu; |
2011 | ||
9aba60fe SR |
2012 | /* If we are looking at one CPU buffer, only check that one */ |
2013 | if (iter->cpu_file != TRACE_PIPE_ALL_CPU) { | |
2014 | cpu = iter->cpu_file; | |
2015 | if (iter->buffer_iter[cpu]) { | |
2016 | if (!ring_buffer_iter_empty(iter->buffer_iter[cpu])) | |
2017 | return 0; | |
2018 | } else { | |
2019 | if (!ring_buffer_empty_cpu(iter->tr->buffer, cpu)) | |
2020 | return 0; | |
2021 | } | |
2022 | return 1; | |
2023 | } | |
2024 | ||
ab46428c | 2025 | for_each_tracing_cpu(cpu) { |
d769041f SR |
2026 | if (iter->buffer_iter[cpu]) { |
2027 | if (!ring_buffer_iter_empty(iter->buffer_iter[cpu])) | |
2028 | return 0; | |
2029 | } else { | |
2030 | if (!ring_buffer_empty_cpu(iter->tr->buffer, cpu)) | |
2031 | return 0; | |
2032 | } | |
bc0c38d1 | 2033 | } |
d769041f | 2034 | |
797d3712 | 2035 | return 1; |
bc0c38d1 SR |
2036 | } |
2037 | ||
4f535968 | 2038 | /* Called with trace_event_read_lock() held. */ |
955b61e5 | 2039 | enum print_line_t print_trace_line(struct trace_iterator *iter) |
f9896bf3 | 2040 | { |
2c4f035f FW |
2041 | enum print_line_t ret; |
2042 | ||
ee5e51f5 JO |
2043 | if (iter->lost_events && |
2044 | !trace_seq_printf(&iter->seq, "CPU:%d [LOST %lu EVENTS]\n", | |
2045 | iter->cpu, iter->lost_events)) | |
2046 | return TRACE_TYPE_PARTIAL_LINE; | |
bc21b478 | 2047 | |
2c4f035f FW |
2048 | if (iter->trace && iter->trace->print_line) { |
2049 | ret = iter->trace->print_line(iter); | |
2050 | if (ret != TRACE_TYPE_UNHANDLED) | |
2051 | return ret; | |
2052 | } | |
72829bc3 | 2053 | |
48ead020 FW |
2054 | if (iter->ent->type == TRACE_BPRINT && |
2055 | trace_flags & TRACE_ITER_PRINTK && | |
2056 | trace_flags & TRACE_ITER_PRINTK_MSGONLY) | |
5ef841f6 | 2057 | return trace_print_bprintk_msg_only(iter); |
48ead020 | 2058 | |
66896a85 FW |
2059 | if (iter->ent->type == TRACE_PRINT && |
2060 | trace_flags & TRACE_ITER_PRINTK && | |
2061 | trace_flags & TRACE_ITER_PRINTK_MSGONLY) | |
5ef841f6 | 2062 | return trace_print_printk_msg_only(iter); |
66896a85 | 2063 | |
cb0f12aa IM |
2064 | if (trace_flags & TRACE_ITER_BIN) |
2065 | return print_bin_fmt(iter); | |
2066 | ||
5e3ca0ec IM |
2067 | if (trace_flags & TRACE_ITER_HEX) |
2068 | return print_hex_fmt(iter); | |
2069 | ||
f9896bf3 IM |
2070 | if (trace_flags & TRACE_ITER_RAW) |
2071 | return print_raw_fmt(iter); | |
2072 | ||
f9896bf3 IM |
2073 | return print_trace_fmt(iter); |
2074 | } | |
2075 | ||
62b915f1 JO |
2076 | void trace_default_header(struct seq_file *m) |
2077 | { | |
2078 | struct trace_iterator *iter = m->private; | |
2079 | ||
f56e7f8e JO |
2080 | if (!(trace_flags & TRACE_ITER_CONTEXT_INFO)) |
2081 | return; | |
2082 | ||
62b915f1 JO |
2083 | if (iter->iter_flags & TRACE_FILE_LAT_FMT) { |
2084 | /* print nothing if the buffers are empty */ | |
2085 | if (trace_empty(iter)) | |
2086 | return; | |
2087 | print_trace_header(m, iter); | |
2088 | if (!(trace_flags & TRACE_ITER_VERBOSE)) | |
2089 | print_lat_help_header(m); | |
2090 | } else { | |
2091 | if (!(trace_flags & TRACE_ITER_VERBOSE)) | |
2092 | print_func_help_header(m); | |
2093 | } | |
2094 | } | |
2095 | ||
bc0c38d1 SR |
2096 | static int s_show(struct seq_file *m, void *v) |
2097 | { | |
2098 | struct trace_iterator *iter = v; | |
a63ce5b3 | 2099 | int ret; |
bc0c38d1 SR |
2100 | |
2101 | if (iter->ent == NULL) { | |
2102 | if (iter->tr) { | |
2103 | seq_printf(m, "# tracer: %s\n", iter->trace->name); | |
2104 | seq_puts(m, "#\n"); | |
2105 | } | |
8bba1bf5 MM |
2106 | if (iter->trace && iter->trace->print_header) |
2107 | iter->trace->print_header(m); | |
62b915f1 JO |
2108 | else |
2109 | trace_default_header(m); | |
2110 | ||
a63ce5b3 SR |
2111 | } else if (iter->leftover) { |
2112 | /* | |
2113 | * If we filled the seq_file buffer earlier, we | |
2114 | * want to just show it now. | |
2115 | */ | |
2116 | ret = trace_print_seq(m, &iter->seq); | |
2117 | ||
2118 | /* ret should this time be zero, but you never know */ | |
2119 | iter->leftover = ret; | |
2120 | ||
bc0c38d1 | 2121 | } else { |
f9896bf3 | 2122 | print_trace_line(iter); |
a63ce5b3 SR |
2123 | ret = trace_print_seq(m, &iter->seq); |
2124 | /* | |
2125 | * If we overflow the seq_file buffer, then it will | |
2126 | * ask us for this data again at start up. | |
2127 | * Use that instead. | |
2128 | * ret is 0 if seq_file write succeeded. | |
2129 | * -1 otherwise. | |
2130 | */ | |
2131 | iter->leftover = ret; | |
bc0c38d1 SR |
2132 | } |
2133 | ||
2134 | return 0; | |
2135 | } | |
2136 | ||
88e9d34c | 2137 | static const struct seq_operations tracer_seq_ops = { |
4bf39a94 IM |
2138 | .start = s_start, |
2139 | .next = s_next, | |
2140 | .stop = s_stop, | |
2141 | .show = s_show, | |
bc0c38d1 SR |
2142 | }; |
2143 | ||
e309b41d | 2144 | static struct trace_iterator * |
85a2f9b4 | 2145 | __tracing_open(struct inode *inode, struct file *file) |
bc0c38d1 | 2146 | { |
b04cc6b1 | 2147 | long cpu_file = (long) inode->i_private; |
85a2f9b4 | 2148 | void *fail_ret = ERR_PTR(-ENOMEM); |
bc0c38d1 | 2149 | struct trace_iterator *iter; |
3928a8a2 | 2150 | struct seq_file *m; |
85a2f9b4 | 2151 | int cpu, ret; |
bc0c38d1 | 2152 | |
85a2f9b4 SR |
2153 | if (tracing_disabled) |
2154 | return ERR_PTR(-ENODEV); | |
60a11774 | 2155 | |
bc0c38d1 | 2156 | iter = kzalloc(sizeof(*iter), GFP_KERNEL); |
85a2f9b4 SR |
2157 | if (!iter) |
2158 | return ERR_PTR(-ENOMEM); | |
bc0c38d1 | 2159 | |
d7350c3f FW |
2160 | /* |
2161 | * We make a copy of the current tracer to avoid concurrent | |
2162 | * changes on it while we are reading. | |
2163 | */ | |
bc0c38d1 | 2164 | mutex_lock(&trace_types_lock); |
d7350c3f | 2165 | iter->trace = kzalloc(sizeof(*iter->trace), GFP_KERNEL); |
85a2f9b4 | 2166 | if (!iter->trace) |
d7350c3f | 2167 | goto fail; |
85a2f9b4 | 2168 | |
d7350c3f FW |
2169 | if (current_trace) |
2170 | *iter->trace = *current_trace; | |
2171 | ||
79f55997 | 2172 | if (!zalloc_cpumask_var(&iter->started, GFP_KERNEL)) |
b0dfa978 FW |
2173 | goto fail; |
2174 | ||
bc0c38d1 SR |
2175 | if (current_trace && current_trace->print_max) |
2176 | iter->tr = &max_tr; | |
2177 | else | |
b04cc6b1 | 2178 | iter->tr = &global_trace; |
bc0c38d1 | 2179 | iter->pos = -1; |
d7350c3f | 2180 | mutex_init(&iter->mutex); |
b04cc6b1 | 2181 | iter->cpu_file = cpu_file; |
bc0c38d1 | 2182 | |
8bba1bf5 MM |
2183 | /* Notify the tracer early; before we stop tracing. */ |
2184 | if (iter->trace && iter->trace->open) | |
a93751ca | 2185 | iter->trace->open(iter); |
8bba1bf5 | 2186 | |
12ef7d44 SR |
2187 | /* Annotate start of buffers if we had overruns */ |
2188 | if (ring_buffer_overruns(iter->tr->buffer)) | |
2189 | iter->iter_flags |= TRACE_FILE_ANNOTATE; | |
2190 | ||
2f26ebd5 SR |
2191 | /* stop the trace while dumping */ |
2192 | tracing_stop(); | |
2193 | ||
b04cc6b1 FW |
2194 | if (iter->cpu_file == TRACE_PIPE_ALL_CPU) { |
2195 | for_each_tracing_cpu(cpu) { | |
b04cc6b1 | 2196 | iter->buffer_iter[cpu] = |
72c9ddfd DM |
2197 | ring_buffer_read_prepare(iter->tr->buffer, cpu); |
2198 | } | |
2199 | ring_buffer_read_prepare_sync(); | |
2200 | for_each_tracing_cpu(cpu) { | |
2201 | ring_buffer_read_start(iter->buffer_iter[cpu]); | |
2f26ebd5 | 2202 | tracing_iter_reset(iter, cpu); |
b04cc6b1 FW |
2203 | } |
2204 | } else { | |
2205 | cpu = iter->cpu_file; | |
3928a8a2 | 2206 | iter->buffer_iter[cpu] = |
72c9ddfd DM |
2207 | ring_buffer_read_prepare(iter->tr->buffer, cpu); |
2208 | ring_buffer_read_prepare_sync(); | |
2209 | ring_buffer_read_start(iter->buffer_iter[cpu]); | |
2f26ebd5 | 2210 | tracing_iter_reset(iter, cpu); |
3928a8a2 SR |
2211 | } |
2212 | ||
85a2f9b4 SR |
2213 | ret = seq_open(file, &tracer_seq_ops); |
2214 | if (ret < 0) { | |
2215 | fail_ret = ERR_PTR(ret); | |
3928a8a2 | 2216 | goto fail_buffer; |
85a2f9b4 | 2217 | } |
bc0c38d1 | 2218 | |
3928a8a2 SR |
2219 | m = file->private_data; |
2220 | m->private = iter; | |
bc0c38d1 | 2221 | |
bc0c38d1 SR |
2222 | mutex_unlock(&trace_types_lock); |
2223 | ||
bc0c38d1 | 2224 | return iter; |
3928a8a2 SR |
2225 | |
2226 | fail_buffer: | |
2227 | for_each_tracing_cpu(cpu) { | |
2228 | if (iter->buffer_iter[cpu]) | |
2229 | ring_buffer_read_finish(iter->buffer_iter[cpu]); | |
2230 | } | |
b0dfa978 | 2231 | free_cpumask_var(iter->started); |
2f26ebd5 | 2232 | tracing_start(); |
d7350c3f | 2233 | fail: |
3928a8a2 | 2234 | mutex_unlock(&trace_types_lock); |
d7350c3f | 2235 | kfree(iter->trace); |
0bb943c7 | 2236 | kfree(iter); |
3928a8a2 | 2237 | |
85a2f9b4 | 2238 | return fail_ret; |
bc0c38d1 SR |
2239 | } |
2240 | ||
2241 | int tracing_open_generic(struct inode *inode, struct file *filp) | |
2242 | { | |
60a11774 SR |
2243 | if (tracing_disabled) |
2244 | return -ENODEV; | |
2245 | ||
bc0c38d1 SR |
2246 | filp->private_data = inode->i_private; |
2247 | return 0; | |
2248 | } | |
2249 | ||
4fd27358 | 2250 | static int tracing_release(struct inode *inode, struct file *file) |
bc0c38d1 | 2251 | { |
907f2784 | 2252 | struct seq_file *m = file->private_data; |
4acd4d00 | 2253 | struct trace_iterator *iter; |
3928a8a2 | 2254 | int cpu; |
bc0c38d1 | 2255 | |
4acd4d00 SR |
2256 | if (!(file->f_mode & FMODE_READ)) |
2257 | return 0; | |
2258 | ||
2259 | iter = m->private; | |
2260 | ||
bc0c38d1 | 2261 | mutex_lock(&trace_types_lock); |
3928a8a2 SR |
2262 | for_each_tracing_cpu(cpu) { |
2263 | if (iter->buffer_iter[cpu]) | |
2264 | ring_buffer_read_finish(iter->buffer_iter[cpu]); | |
2265 | } | |
2266 | ||
bc0c38d1 SR |
2267 | if (iter->trace && iter->trace->close) |
2268 | iter->trace->close(iter); | |
2269 | ||
2270 | /* reenable tracing if it was previously enabled */ | |
9036990d | 2271 | tracing_start(); |
bc0c38d1 SR |
2272 | mutex_unlock(&trace_types_lock); |
2273 | ||
2274 | seq_release(inode, file); | |
d7350c3f | 2275 | mutex_destroy(&iter->mutex); |
b0dfa978 | 2276 | free_cpumask_var(iter->started); |
d7350c3f | 2277 | kfree(iter->trace); |
bc0c38d1 SR |
2278 | kfree(iter); |
2279 | return 0; | |
2280 | } | |
2281 | ||
2282 | static int tracing_open(struct inode *inode, struct file *file) | |
2283 | { | |
85a2f9b4 SR |
2284 | struct trace_iterator *iter; |
2285 | int ret = 0; | |
bc0c38d1 | 2286 | |
4acd4d00 SR |
2287 | /* If this file was open for write, then erase contents */ |
2288 | if ((file->f_mode & FMODE_WRITE) && | |
8650ae32 | 2289 | (file->f_flags & O_TRUNC)) { |
4acd4d00 | 2290 | long cpu = (long) inode->i_private; |
bc0c38d1 | 2291 | |
4acd4d00 SR |
2292 | if (cpu == TRACE_PIPE_ALL_CPU) |
2293 | tracing_reset_online_cpus(&global_trace); | |
2294 | else | |
2295 | tracing_reset(&global_trace, cpu); | |
2296 | } | |
bc0c38d1 | 2297 | |
4acd4d00 SR |
2298 | if (file->f_mode & FMODE_READ) { |
2299 | iter = __tracing_open(inode, file); | |
2300 | if (IS_ERR(iter)) | |
2301 | ret = PTR_ERR(iter); | |
2302 | else if (trace_flags & TRACE_ITER_LATENCY_FMT) | |
2303 | iter->iter_flags |= TRACE_FILE_LAT_FMT; | |
2304 | } | |
bc0c38d1 SR |
2305 | return ret; |
2306 | } | |
2307 | ||
e309b41d | 2308 | static void * |
bc0c38d1 SR |
2309 | t_next(struct seq_file *m, void *v, loff_t *pos) |
2310 | { | |
f129e965 | 2311 | struct tracer *t = v; |
bc0c38d1 SR |
2312 | |
2313 | (*pos)++; | |
2314 | ||
2315 | if (t) | |
2316 | t = t->next; | |
2317 | ||
bc0c38d1 SR |
2318 | return t; |
2319 | } | |
2320 | ||
2321 | static void *t_start(struct seq_file *m, loff_t *pos) | |
2322 | { | |
f129e965 | 2323 | struct tracer *t; |
bc0c38d1 SR |
2324 | loff_t l = 0; |
2325 | ||
2326 | mutex_lock(&trace_types_lock); | |
f129e965 | 2327 | for (t = trace_types; t && l < *pos; t = t_next(m, t, &l)) |
bc0c38d1 SR |
2328 | ; |
2329 | ||
2330 | return t; | |
2331 | } | |
2332 | ||
2333 | static void t_stop(struct seq_file *m, void *p) | |
2334 | { | |
2335 | mutex_unlock(&trace_types_lock); | |
2336 | } | |
2337 | ||
2338 | static int t_show(struct seq_file *m, void *v) | |
2339 | { | |
2340 | struct tracer *t = v; | |
2341 | ||
2342 | if (!t) | |
2343 | return 0; | |
2344 | ||
2345 | seq_printf(m, "%s", t->name); | |
2346 | if (t->next) | |
2347 | seq_putc(m, ' '); | |
2348 | else | |
2349 | seq_putc(m, '\n'); | |
2350 | ||
2351 | return 0; | |
2352 | } | |
2353 | ||
88e9d34c | 2354 | static const struct seq_operations show_traces_seq_ops = { |
4bf39a94 IM |
2355 | .start = t_start, |
2356 | .next = t_next, | |
2357 | .stop = t_stop, | |
2358 | .show = t_show, | |
bc0c38d1 SR |
2359 | }; |
2360 | ||
2361 | static int show_traces_open(struct inode *inode, struct file *file) | |
2362 | { | |
60a11774 SR |
2363 | if (tracing_disabled) |
2364 | return -ENODEV; | |
2365 | ||
f129e965 | 2366 | return seq_open(file, &show_traces_seq_ops); |
bc0c38d1 SR |
2367 | } |
2368 | ||
4acd4d00 SR |
2369 | static ssize_t |
2370 | tracing_write_stub(struct file *filp, const char __user *ubuf, | |
2371 | size_t count, loff_t *ppos) | |
2372 | { | |
2373 | return count; | |
2374 | } | |
2375 | ||
364829b1 SP |
2376 | static loff_t tracing_seek(struct file *file, loff_t offset, int origin) |
2377 | { | |
2378 | if (file->f_mode & FMODE_READ) | |
2379 | return seq_lseek(file, offset, origin); | |
2380 | else | |
2381 | return 0; | |
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, |
364829b1 | 2388 | .llseek = tracing_seek, |
4bf39a94 | 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, | |
b444786f | 2396 | .llseek = seq_lseek, |
c7078de1 IM |
2397 | }; |
2398 | ||
36dfe925 IM |
2399 | /* |
2400 | * Only trace on a CPU if the bitmask is set: | |
2401 | */ | |
9e01c1b7 | 2402 | static cpumask_var_t tracing_cpumask; |
36dfe925 IM |
2403 | |
2404 | /* | |
2405 | * The tracer itself will not take this lock, but still we want | |
2406 | * to provide a consistent cpumask to user-space: | |
2407 | */ | |
2408 | static DEFINE_MUTEX(tracing_cpumask_update_lock); | |
2409 | ||
2410 | /* | |
2411 | * Temporary storage for the character representation of the | |
2412 | * CPU bitmask (and one more byte for the newline): | |
2413 | */ | |
2414 | static char mask_str[NR_CPUS + 1]; | |
2415 | ||
c7078de1 IM |
2416 | static ssize_t |
2417 | tracing_cpumask_read(struct file *filp, char __user *ubuf, | |
2418 | size_t count, loff_t *ppos) | |
2419 | { | |
36dfe925 | 2420 | int len; |
c7078de1 IM |
2421 | |
2422 | mutex_lock(&tracing_cpumask_update_lock); | |
36dfe925 | 2423 | |
9e01c1b7 | 2424 | len = cpumask_scnprintf(mask_str, count, tracing_cpumask); |
36dfe925 IM |
2425 | if (count - len < 2) { |
2426 | count = -EINVAL; | |
2427 | goto out_err; | |
2428 | } | |
2429 | len += sprintf(mask_str + len, "\n"); | |
2430 | count = simple_read_from_buffer(ubuf, count, ppos, mask_str, NR_CPUS+1); | |
2431 | ||
2432 | out_err: | |
c7078de1 IM |
2433 | mutex_unlock(&tracing_cpumask_update_lock); |
2434 | ||
2435 | return count; | |
2436 | } | |
2437 | ||
2438 | static ssize_t | |
2439 | tracing_cpumask_write(struct file *filp, const char __user *ubuf, | |
2440 | size_t count, loff_t *ppos) | |
2441 | { | |
36dfe925 | 2442 | int err, cpu; |
9e01c1b7 RR |
2443 | cpumask_var_t tracing_cpumask_new; |
2444 | ||
2445 | if (!alloc_cpumask_var(&tracing_cpumask_new, GFP_KERNEL)) | |
2446 | return -ENOMEM; | |
c7078de1 | 2447 | |
9e01c1b7 | 2448 | err = cpumask_parse_user(ubuf, count, tracing_cpumask_new); |
c7078de1 | 2449 | if (err) |
36dfe925 IM |
2450 | goto err_unlock; |
2451 | ||
215368e8 LZ |
2452 | mutex_lock(&tracing_cpumask_update_lock); |
2453 | ||
a5e25883 | 2454 | local_irq_disable(); |
0199c4e6 | 2455 | arch_spin_lock(&ftrace_max_lock); |
ab46428c | 2456 | for_each_tracing_cpu(cpu) { |
36dfe925 IM |
2457 | /* |
2458 | * Increase/decrease the disabled counter if we are | |
2459 | * about to flip a bit in the cpumask: | |
2460 | */ | |
9e01c1b7 RR |
2461 | if (cpumask_test_cpu(cpu, tracing_cpumask) && |
2462 | !cpumask_test_cpu(cpu, tracing_cpumask_new)) { | |
36dfe925 IM |
2463 | atomic_inc(&global_trace.data[cpu]->disabled); |
2464 | } | |
9e01c1b7 RR |
2465 | if (!cpumask_test_cpu(cpu, tracing_cpumask) && |
2466 | cpumask_test_cpu(cpu, tracing_cpumask_new)) { | |
36dfe925 IM |
2467 | atomic_dec(&global_trace.data[cpu]->disabled); |
2468 | } | |
2469 | } | |
0199c4e6 | 2470 | arch_spin_unlock(&ftrace_max_lock); |
a5e25883 | 2471 | local_irq_enable(); |
36dfe925 | 2472 | |
9e01c1b7 | 2473 | cpumask_copy(tracing_cpumask, tracing_cpumask_new); |
36dfe925 IM |
2474 | |
2475 | mutex_unlock(&tracing_cpumask_update_lock); | |
9e01c1b7 | 2476 | free_cpumask_var(tracing_cpumask_new); |
c7078de1 IM |
2477 | |
2478 | return count; | |
36dfe925 IM |
2479 | |
2480 | err_unlock: | |
215368e8 | 2481 | free_cpumask_var(tracing_cpumask_new); |
36dfe925 IM |
2482 | |
2483 | return err; | |
c7078de1 IM |
2484 | } |
2485 | ||
5e2336a0 | 2486 | static const struct file_operations tracing_cpumask_fops = { |
c7078de1 IM |
2487 | .open = tracing_open_generic, |
2488 | .read = tracing_cpumask_read, | |
2489 | .write = tracing_cpumask_write, | |
b444786f | 2490 | .llseek = generic_file_llseek, |
bc0c38d1 SR |
2491 | }; |
2492 | ||
fdb372ed | 2493 | static int tracing_trace_options_show(struct seq_file *m, void *v) |
bc0c38d1 | 2494 | { |
d8e83d26 SR |
2495 | struct tracer_opt *trace_opts; |
2496 | u32 tracer_flags; | |
d8e83d26 | 2497 | int i; |
adf9f195 | 2498 | |
d8e83d26 SR |
2499 | mutex_lock(&trace_types_lock); |
2500 | tracer_flags = current_trace->flags->val; | |
2501 | trace_opts = current_trace->flags->opts; | |
2502 | ||
bc0c38d1 SR |
2503 | for (i = 0; trace_options[i]; i++) { |
2504 | if (trace_flags & (1 << i)) | |
fdb372ed | 2505 | seq_printf(m, "%s\n", trace_options[i]); |
bc0c38d1 | 2506 | else |
fdb372ed | 2507 | seq_printf(m, "no%s\n", trace_options[i]); |
bc0c38d1 SR |
2508 | } |
2509 | ||
adf9f195 FW |
2510 | for (i = 0; trace_opts[i].name; i++) { |
2511 | if (tracer_flags & trace_opts[i].bit) | |
fdb372ed | 2512 | seq_printf(m, "%s\n", trace_opts[i].name); |
adf9f195 | 2513 | else |
fdb372ed | 2514 | seq_printf(m, "no%s\n", trace_opts[i].name); |
adf9f195 | 2515 | } |
d8e83d26 | 2516 | mutex_unlock(&trace_types_lock); |
adf9f195 | 2517 | |
fdb372ed | 2518 | return 0; |
bc0c38d1 | 2519 | } |
bc0c38d1 | 2520 | |
8d18eaaf LZ |
2521 | static int __set_tracer_option(struct tracer *trace, |
2522 | struct tracer_flags *tracer_flags, | |
2523 | struct tracer_opt *opts, int neg) | |
2524 | { | |
2525 | int ret; | |
bc0c38d1 | 2526 | |
8d18eaaf LZ |
2527 | ret = trace->set_flag(tracer_flags->val, opts->bit, !neg); |
2528 | if (ret) | |
2529 | return ret; | |
2530 | ||
2531 | if (neg) | |
2532 | tracer_flags->val &= ~opts->bit; | |
2533 | else | |
2534 | tracer_flags->val |= opts->bit; | |
2535 | return 0; | |
bc0c38d1 SR |
2536 | } |
2537 | ||
adf9f195 FW |
2538 | /* Try to assign a tracer specific option */ |
2539 | static int set_tracer_option(struct tracer *trace, char *cmp, int neg) | |
2540 | { | |
7770841e | 2541 | struct tracer_flags *tracer_flags = trace->flags; |
adf9f195 | 2542 | struct tracer_opt *opts = NULL; |
8d18eaaf | 2543 | int i; |
adf9f195 | 2544 | |
7770841e Z |
2545 | for (i = 0; tracer_flags->opts[i].name; i++) { |
2546 | opts = &tracer_flags->opts[i]; | |
adf9f195 | 2547 | |
8d18eaaf LZ |
2548 | if (strcmp(cmp, opts->name) == 0) |
2549 | return __set_tracer_option(trace, trace->flags, | |
2550 | opts, neg); | |
adf9f195 | 2551 | } |
adf9f195 | 2552 | |
8d18eaaf | 2553 | return -EINVAL; |
adf9f195 FW |
2554 | } |
2555 | ||
af4617bd SR |
2556 | static void set_tracer_flags(unsigned int mask, int enabled) |
2557 | { | |
2558 | /* do nothing if flag is already set */ | |
2559 | if (!!(trace_flags & mask) == !!enabled) | |
2560 | return; | |
2561 | ||
2562 | if (enabled) | |
2563 | trace_flags |= mask; | |
2564 | else | |
2565 | trace_flags &= ~mask; | |
e870e9a1 LZ |
2566 | |
2567 | if (mask == TRACE_ITER_RECORD_CMD) | |
2568 | trace_event_enable_cmd_record(enabled); | |
750912fa DS |
2569 | |
2570 | if (mask == TRACE_ITER_OVERWRITE) | |
2571 | ring_buffer_change_overwrite(global_trace.buffer, enabled); | |
af4617bd SR |
2572 | } |
2573 | ||
bc0c38d1 | 2574 | static ssize_t |
ee6bce52 | 2575 | tracing_trace_options_write(struct file *filp, const char __user *ubuf, |
bc0c38d1 SR |
2576 | size_t cnt, loff_t *ppos) |
2577 | { | |
2578 | char buf[64]; | |
8d18eaaf | 2579 | char *cmp; |
bc0c38d1 | 2580 | int neg = 0; |
adf9f195 | 2581 | int ret; |
bc0c38d1 SR |
2582 | int i; |
2583 | ||
cffae437 SR |
2584 | if (cnt >= sizeof(buf)) |
2585 | return -EINVAL; | |
bc0c38d1 SR |
2586 | |
2587 | if (copy_from_user(&buf, ubuf, cnt)) | |
2588 | return -EFAULT; | |
2589 | ||
2590 | buf[cnt] = 0; | |
8d18eaaf | 2591 | cmp = strstrip(buf); |
bc0c38d1 | 2592 | |
8d18eaaf | 2593 | if (strncmp(cmp, "no", 2) == 0) { |
bc0c38d1 SR |
2594 | neg = 1; |
2595 | cmp += 2; | |
2596 | } | |
2597 | ||
2598 | for (i = 0; trace_options[i]; i++) { | |
8d18eaaf | 2599 | if (strcmp(cmp, trace_options[i]) == 0) { |
af4617bd | 2600 | set_tracer_flags(1 << i, !neg); |
bc0c38d1 SR |
2601 | break; |
2602 | } | |
2603 | } | |
adf9f195 FW |
2604 | |
2605 | /* If no option could be set, test the specific tracer options */ | |
2606 | if (!trace_options[i]) { | |
d8e83d26 | 2607 | mutex_lock(&trace_types_lock); |
adf9f195 | 2608 | ret = set_tracer_option(current_trace, cmp, neg); |
d8e83d26 | 2609 | mutex_unlock(&trace_types_lock); |
adf9f195 FW |
2610 | if (ret) |
2611 | return ret; | |
2612 | } | |
bc0c38d1 | 2613 | |
cf8517cf | 2614 | *ppos += cnt; |
bc0c38d1 SR |
2615 | |
2616 | return cnt; | |
2617 | } | |
2618 | ||
fdb372ed LZ |
2619 | static int tracing_trace_options_open(struct inode *inode, struct file *file) |
2620 | { | |
2621 | if (tracing_disabled) | |
2622 | return -ENODEV; | |
2623 | return single_open(file, tracing_trace_options_show, NULL); | |
2624 | } | |
2625 | ||
5e2336a0 | 2626 | static const struct file_operations tracing_iter_fops = { |
fdb372ed LZ |
2627 | .open = tracing_trace_options_open, |
2628 | .read = seq_read, | |
2629 | .llseek = seq_lseek, | |
2630 | .release = single_release, | |
ee6bce52 | 2631 | .write = tracing_trace_options_write, |
bc0c38d1 SR |
2632 | }; |
2633 | ||
7bd2f24c IM |
2634 | static const char readme_msg[] = |
2635 | "tracing mini-HOWTO:\n\n" | |
156f5a78 GL |
2636 | "# mount -t debugfs nodev /sys/kernel/debug\n\n" |
2637 | "# cat /sys/kernel/debug/tracing/available_tracers\n" | |
bc2b6871 | 2638 | "wakeup preemptirqsoff preemptoff irqsoff function sched_switch nop\n\n" |
156f5a78 | 2639 | "# cat /sys/kernel/debug/tracing/current_tracer\n" |
bc2b6871 | 2640 | "nop\n" |
156f5a78 GL |
2641 | "# echo sched_switch > /sys/kernel/debug/tracing/current_tracer\n" |
2642 | "# cat /sys/kernel/debug/tracing/current_tracer\n" | |
7bd2f24c | 2643 | "sched_switch\n" |
156f5a78 | 2644 | "# cat /sys/kernel/debug/tracing/trace_options\n" |
7bd2f24c | 2645 | "noprint-parent nosym-offset nosym-addr noverbose\n" |
156f5a78 GL |
2646 | "# echo print-parent > /sys/kernel/debug/tracing/trace_options\n" |
2647 | "# echo 1 > /sys/kernel/debug/tracing/tracing_enabled\n" | |
2648 | "# cat /sys/kernel/debug/tracing/trace > /tmp/trace.txt\n" | |
2649 | "# echo 0 > /sys/kernel/debug/tracing/tracing_enabled\n" | |
7bd2f24c IM |
2650 | ; |
2651 | ||
2652 | static ssize_t | |
2653 | tracing_readme_read(struct file *filp, char __user *ubuf, | |
2654 | size_t cnt, loff_t *ppos) | |
2655 | { | |
2656 | return simple_read_from_buffer(ubuf, cnt, ppos, | |
2657 | readme_msg, strlen(readme_msg)); | |
2658 | } | |
2659 | ||
5e2336a0 | 2660 | static const struct file_operations tracing_readme_fops = { |
c7078de1 IM |
2661 | .open = tracing_open_generic, |
2662 | .read = tracing_readme_read, | |
b444786f | 2663 | .llseek = generic_file_llseek, |
7bd2f24c IM |
2664 | }; |
2665 | ||
69abe6a5 AP |
2666 | static ssize_t |
2667 | tracing_saved_cmdlines_read(struct file *file, char __user *ubuf, | |
2668 | size_t cnt, loff_t *ppos) | |
2669 | { | |
2670 | char *buf_comm; | |
2671 | char *file_buf; | |
2672 | char *buf; | |
2673 | int len = 0; | |
2674 | int pid; | |
2675 | int i; | |
2676 | ||
2677 | file_buf = kmalloc(SAVED_CMDLINES*(16+TASK_COMM_LEN), GFP_KERNEL); | |
2678 | if (!file_buf) | |
2679 | return -ENOMEM; | |
2680 | ||
2681 | buf_comm = kmalloc(TASK_COMM_LEN, GFP_KERNEL); | |
2682 | if (!buf_comm) { | |
2683 | kfree(file_buf); | |
2684 | return -ENOMEM; | |
2685 | } | |
2686 | ||
2687 | buf = file_buf; | |
2688 | ||
2689 | for (i = 0; i < SAVED_CMDLINES; i++) { | |
2690 | int r; | |
2691 | ||
2692 | pid = map_cmdline_to_pid[i]; | |
2693 | if (pid == -1 || pid == NO_CMDLINE_MAP) | |
2694 | continue; | |
2695 | ||
2696 | trace_find_cmdline(pid, buf_comm); | |
2697 | r = sprintf(buf, "%d %s\n", pid, buf_comm); | |
2698 | buf += r; | |
2699 | len += r; | |
2700 | } | |
2701 | ||
2702 | len = simple_read_from_buffer(ubuf, cnt, ppos, | |
2703 | file_buf, len); | |
2704 | ||
2705 | kfree(file_buf); | |
2706 | kfree(buf_comm); | |
2707 | ||
2708 | return len; | |
2709 | } | |
2710 | ||
2711 | static const struct file_operations tracing_saved_cmdlines_fops = { | |
2712 | .open = tracing_open_generic, | |
2713 | .read = tracing_saved_cmdlines_read, | |
b444786f | 2714 | .llseek = generic_file_llseek, |
69abe6a5 AP |
2715 | }; |
2716 | ||
bc0c38d1 SR |
2717 | static ssize_t |
2718 | tracing_ctrl_read(struct file *filp, char __user *ubuf, | |
2719 | size_t cnt, loff_t *ppos) | |
2720 | { | |
bc0c38d1 SR |
2721 | char buf[64]; |
2722 | int r; | |
2723 | ||
9036990d | 2724 | r = sprintf(buf, "%u\n", tracer_enabled); |
4e3c3333 | 2725 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, r); |
bc0c38d1 SR |
2726 | } |
2727 | ||
2728 | static ssize_t | |
2729 | tracing_ctrl_write(struct file *filp, const char __user *ubuf, | |
2730 | size_t cnt, loff_t *ppos) | |
2731 | { | |
2732 | struct trace_array *tr = filp->private_data; | |
5e39841c | 2733 | unsigned long val; |
c6caeeb1 | 2734 | int ret; |
bc0c38d1 | 2735 | |
22fe9b54 PH |
2736 | ret = kstrtoul_from_user(ubuf, cnt, 10, &val); |
2737 | if (ret) | |
c6caeeb1 | 2738 | return ret; |
bc0c38d1 SR |
2739 | |
2740 | val = !!val; | |
2741 | ||
2742 | mutex_lock(&trace_types_lock); | |
9036990d | 2743 | if (tracer_enabled ^ val) { |
6752ab4a SR |
2744 | |
2745 | /* Only need to warn if this is used to change the state */ | |
2746 | WARN_ONCE(1, "tracing_enabled is deprecated. Use tracing_on"); | |
2747 | ||
9036990d | 2748 | if (val) { |
bc0c38d1 | 2749 | tracer_enabled = 1; |
9036990d SR |
2750 | if (current_trace->start) |
2751 | current_trace->start(tr); | |
2752 | tracing_start(); | |
2753 | } else { | |
bc0c38d1 | 2754 | tracer_enabled = 0; |
9036990d SR |
2755 | tracing_stop(); |
2756 | if (current_trace->stop) | |
2757 | current_trace->stop(tr); | |
2758 | } | |
bc0c38d1 SR |
2759 | } |
2760 | mutex_unlock(&trace_types_lock); | |
2761 | ||
cf8517cf | 2762 | *ppos += cnt; |
bc0c38d1 SR |
2763 | |
2764 | return cnt; | |
2765 | } | |
2766 | ||
2767 | static ssize_t | |
2768 | tracing_set_trace_read(struct file *filp, char __user *ubuf, | |
2769 | size_t cnt, loff_t *ppos) | |
2770 | { | |
ee6c2c1b | 2771 | char buf[MAX_TRACER_SIZE+2]; |
bc0c38d1 SR |
2772 | int r; |
2773 | ||
2774 | mutex_lock(&trace_types_lock); | |
2775 | if (current_trace) | |
2776 | r = sprintf(buf, "%s\n", current_trace->name); | |
2777 | else | |
2778 | r = sprintf(buf, "\n"); | |
2779 | mutex_unlock(&trace_types_lock); | |
2780 | ||
4bf39a94 | 2781 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, r); |
bc0c38d1 SR |
2782 | } |
2783 | ||
b6f11df2 ACM |
2784 | int tracer_init(struct tracer *t, struct trace_array *tr) |
2785 | { | |
2786 | tracing_reset_online_cpus(tr); | |
2787 | return t->init(tr); | |
2788 | } | |
2789 | ||
4f271a2a | 2790 | static int __tracing_resize_ring_buffer(unsigned long size) |
73c5162a SR |
2791 | { |
2792 | int ret; | |
2793 | ||
2794 | /* | |
2795 | * If kernel or user changes the size of the ring buffer | |
a123c52b SR |
2796 | * we use the size that was given, and we can forget about |
2797 | * expanding it later. | |
73c5162a SR |
2798 | */ |
2799 | ring_buffer_expanded = 1; | |
2800 | ||
2801 | ret = ring_buffer_resize(global_trace.buffer, size); | |
2802 | if (ret < 0) | |
2803 | return ret; | |
2804 | ||
ef710e10 KM |
2805 | if (!current_trace->use_max_tr) |
2806 | goto out; | |
2807 | ||
73c5162a SR |
2808 | ret = ring_buffer_resize(max_tr.buffer, size); |
2809 | if (ret < 0) { | |
2810 | int r; | |
2811 | ||
2812 | r = ring_buffer_resize(global_trace.buffer, | |
2813 | global_trace.entries); | |
2814 | if (r < 0) { | |
a123c52b SR |
2815 | /* |
2816 | * AARGH! We are left with different | |
2817 | * size max buffer!!!! | |
2818 | * The max buffer is our "snapshot" buffer. | |
2819 | * When a tracer needs a snapshot (one of the | |
2820 | * latency tracers), it swaps the max buffer | |
2821 | * with the saved snap shot. We succeeded to | |
2822 | * update the size of the main buffer, but failed to | |
2823 | * update the size of the max buffer. But when we tried | |
2824 | * to reset the main buffer to the original size, we | |
2825 | * failed there too. This is very unlikely to | |
2826 | * happen, but if it does, warn and kill all | |
2827 | * tracing. | |
2828 | */ | |
73c5162a SR |
2829 | WARN_ON(1); |
2830 | tracing_disabled = 1; | |
2831 | } | |
2832 | return ret; | |
2833 | } | |
2834 | ||
ef710e10 KM |
2835 | max_tr.entries = size; |
2836 | out: | |
73c5162a SR |
2837 | global_trace.entries = size; |
2838 | ||
2839 | return ret; | |
2840 | } | |
2841 | ||
4f271a2a VN |
2842 | static ssize_t tracing_resize_ring_buffer(unsigned long size) |
2843 | { | |
2844 | int cpu, ret = size; | |
2845 | ||
2846 | mutex_lock(&trace_types_lock); | |
2847 | ||
2848 | tracing_stop(); | |
2849 | ||
2850 | /* disable all cpu buffers */ | |
2851 | for_each_tracing_cpu(cpu) { | |
2852 | if (global_trace.data[cpu]) | |
2853 | atomic_inc(&global_trace.data[cpu]->disabled); | |
2854 | if (max_tr.data[cpu]) | |
2855 | atomic_inc(&max_tr.data[cpu]->disabled); | |
2856 | } | |
2857 | ||
2858 | if (size != global_trace.entries) | |
2859 | ret = __tracing_resize_ring_buffer(size); | |
2860 | ||
2861 | if (ret < 0) | |
2862 | ret = -ENOMEM; | |
2863 | ||
2864 | for_each_tracing_cpu(cpu) { | |
2865 | if (global_trace.data[cpu]) | |
2866 | atomic_dec(&global_trace.data[cpu]->disabled); | |
2867 | if (max_tr.data[cpu]) | |
2868 | atomic_dec(&max_tr.data[cpu]->disabled); | |
2869 | } | |
2870 | ||
2871 | tracing_start(); | |
2872 | mutex_unlock(&trace_types_lock); | |
2873 | ||
2874 | return ret; | |
2875 | } | |
2876 | ||
ef710e10 | 2877 | |
1852fcce SR |
2878 | /** |
2879 | * tracing_update_buffers - used by tracing facility to expand ring buffers | |
2880 | * | |
2881 | * To save on memory when the tracing is never used on a system with it | |
2882 | * configured in. The ring buffers are set to a minimum size. But once | |
2883 | * a user starts to use the tracing facility, then they need to grow | |
2884 | * to their default size. | |
2885 | * | |
2886 | * This function is to be called when a tracer is about to be used. | |
2887 | */ | |
2888 | int tracing_update_buffers(void) | |
2889 | { | |
2890 | int ret = 0; | |
2891 | ||
1027fcb2 | 2892 | mutex_lock(&trace_types_lock); |
1852fcce | 2893 | if (!ring_buffer_expanded) |
4f271a2a | 2894 | ret = __tracing_resize_ring_buffer(trace_buf_size); |
1027fcb2 | 2895 | mutex_unlock(&trace_types_lock); |
1852fcce SR |
2896 | |
2897 | return ret; | |
2898 | } | |
2899 | ||
577b785f SR |
2900 | struct trace_option_dentry; |
2901 | ||
2902 | static struct trace_option_dentry * | |
2903 | create_trace_option_files(struct tracer *tracer); | |
2904 | ||
2905 | static void | |
2906 | destroy_trace_option_files(struct trace_option_dentry *topts); | |
2907 | ||
b2821ae6 | 2908 | static int tracing_set_tracer(const char *buf) |
bc0c38d1 | 2909 | { |
577b785f | 2910 | static struct trace_option_dentry *topts; |
bc0c38d1 SR |
2911 | struct trace_array *tr = &global_trace; |
2912 | struct tracer *t; | |
d9e54076 | 2913 | int ret = 0; |
bc0c38d1 | 2914 | |
1027fcb2 SR |
2915 | mutex_lock(&trace_types_lock); |
2916 | ||
73c5162a | 2917 | if (!ring_buffer_expanded) { |
4f271a2a | 2918 | ret = __tracing_resize_ring_buffer(trace_buf_size); |
73c5162a | 2919 | if (ret < 0) |
59f586db | 2920 | goto out; |
73c5162a SR |
2921 | ret = 0; |
2922 | } | |
2923 | ||
bc0c38d1 SR |
2924 | for (t = trace_types; t; t = t->next) { |
2925 | if (strcmp(t->name, buf) == 0) | |
2926 | break; | |
2927 | } | |
c2931e05 FW |
2928 | if (!t) { |
2929 | ret = -EINVAL; | |
2930 | goto out; | |
2931 | } | |
2932 | if (t == current_trace) | |
bc0c38d1 SR |
2933 | goto out; |
2934 | ||
9f029e83 | 2935 | trace_branch_disable(); |
bc0c38d1 SR |
2936 | if (current_trace && current_trace->reset) |
2937 | current_trace->reset(tr); | |
ef710e10 KM |
2938 | if (current_trace && current_trace->use_max_tr) { |
2939 | /* | |
2940 | * We don't free the ring buffer. instead, resize it because | |
2941 | * The max_tr ring buffer has some state (e.g. ring->clock) and | |
2942 | * we want preserve it. | |
2943 | */ | |
2944 | ring_buffer_resize(max_tr.buffer, 1); | |
2945 | max_tr.entries = 1; | |
2946 | } | |
577b785f SR |
2947 | destroy_trace_option_files(topts); |
2948 | ||
bc0c38d1 | 2949 | current_trace = t; |
577b785f SR |
2950 | |
2951 | topts = create_trace_option_files(current_trace); | |
ef710e10 KM |
2952 | if (current_trace->use_max_tr) { |
2953 | ret = ring_buffer_resize(max_tr.buffer, global_trace.entries); | |
2954 | if (ret < 0) | |
2955 | goto out; | |
2956 | max_tr.entries = global_trace.entries; | |
2957 | } | |
577b785f | 2958 | |
1c80025a | 2959 | if (t->init) { |
b6f11df2 | 2960 | ret = tracer_init(t, tr); |
1c80025a FW |
2961 | if (ret) |
2962 | goto out; | |
2963 | } | |
bc0c38d1 | 2964 | |
9f029e83 | 2965 | trace_branch_enable(tr); |
bc0c38d1 SR |
2966 | out: |
2967 | mutex_unlock(&trace_types_lock); | |
2968 | ||
d9e54076 PZ |
2969 | return ret; |
2970 | } | |
2971 | ||
2972 | static ssize_t | |
2973 | tracing_set_trace_write(struct file *filp, const char __user *ubuf, | |
2974 | size_t cnt, loff_t *ppos) | |
2975 | { | |
ee6c2c1b | 2976 | char buf[MAX_TRACER_SIZE+1]; |
d9e54076 PZ |
2977 | int i; |
2978 | size_t ret; | |
e6e7a65a FW |
2979 | int err; |
2980 | ||
2981 | ret = cnt; | |
d9e54076 | 2982 | |
ee6c2c1b LZ |
2983 | if (cnt > MAX_TRACER_SIZE) |
2984 | cnt = MAX_TRACER_SIZE; | |
d9e54076 PZ |
2985 | |
2986 | if (copy_from_user(&buf, ubuf, cnt)) | |
2987 | return -EFAULT; | |
2988 | ||
2989 | buf[cnt] = 0; | |
2990 | ||
2991 | /* strip ending whitespace. */ | |
2992 | for (i = cnt - 1; i > 0 && isspace(buf[i]); i--) | |
2993 | buf[i] = 0; | |
2994 | ||
e6e7a65a FW |
2995 | err = tracing_set_tracer(buf); |
2996 | if (err) | |
2997 | return err; | |
d9e54076 | 2998 | |
cf8517cf | 2999 | *ppos += ret; |
bc0c38d1 | 3000 | |
c2931e05 | 3001 | return ret; |
bc0c38d1 SR |
3002 | } |
3003 | ||
3004 | static ssize_t | |
3005 | tracing_max_lat_read(struct file *filp, char __user *ubuf, | |
3006 | size_t cnt, loff_t *ppos) | |
3007 | { | |
3008 | unsigned long *ptr = filp->private_data; | |
3009 | char buf[64]; | |
3010 | int r; | |
3011 | ||
cffae437 | 3012 | r = snprintf(buf, sizeof(buf), "%ld\n", |
bc0c38d1 | 3013 | *ptr == (unsigned long)-1 ? -1 : nsecs_to_usecs(*ptr)); |
cffae437 SR |
3014 | if (r > sizeof(buf)) |
3015 | r = sizeof(buf); | |
4bf39a94 | 3016 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, r); |
bc0c38d1 SR |
3017 | } |
3018 | ||
3019 | static ssize_t | |
3020 | tracing_max_lat_write(struct file *filp, const char __user *ubuf, | |
3021 | size_t cnt, loff_t *ppos) | |
3022 | { | |
5e39841c | 3023 | unsigned long *ptr = filp->private_data; |
5e39841c | 3024 | unsigned long val; |
c6caeeb1 | 3025 | int ret; |
bc0c38d1 | 3026 | |
22fe9b54 PH |
3027 | ret = kstrtoul_from_user(ubuf, cnt, 10, &val); |
3028 | if (ret) | |
c6caeeb1 | 3029 | return ret; |
bc0c38d1 SR |
3030 | |
3031 | *ptr = val * 1000; | |
3032 | ||
3033 | return cnt; | |
3034 | } | |
3035 | ||
b3806b43 SR |
3036 | static int tracing_open_pipe(struct inode *inode, struct file *filp) |
3037 | { | |
b04cc6b1 | 3038 | long cpu_file = (long) inode->i_private; |
b3806b43 | 3039 | struct trace_iterator *iter; |
b04cc6b1 | 3040 | int ret = 0; |
b3806b43 SR |
3041 | |
3042 | if (tracing_disabled) | |
3043 | return -ENODEV; | |
3044 | ||
b04cc6b1 FW |
3045 | mutex_lock(&trace_types_lock); |
3046 | ||
b3806b43 SR |
3047 | /* create a buffer to store the information to pass to userspace */ |
3048 | iter = kzalloc(sizeof(*iter), GFP_KERNEL); | |
b04cc6b1 FW |
3049 | if (!iter) { |
3050 | ret = -ENOMEM; | |
3051 | goto out; | |
3052 | } | |
b3806b43 | 3053 | |
d7350c3f FW |
3054 | /* |
3055 | * We make a copy of the current tracer to avoid concurrent | |
3056 | * changes on it while we are reading. | |
3057 | */ | |
3058 | iter->trace = kmalloc(sizeof(*iter->trace), GFP_KERNEL); | |
3059 | if (!iter->trace) { | |
3060 | ret = -ENOMEM; | |
3061 | goto fail; | |
3062 | } | |
3063 | if (current_trace) | |
3064 | *iter->trace = *current_trace; | |
3065 | ||
4462344e | 3066 | if (!alloc_cpumask_var(&iter->started, GFP_KERNEL)) { |
b04cc6b1 | 3067 | ret = -ENOMEM; |
d7350c3f | 3068 | goto fail; |
4462344e RR |
3069 | } |
3070 | ||
a309720c | 3071 | /* trace pipe does not show start of buffer */ |
4462344e | 3072 | cpumask_setall(iter->started); |
a309720c | 3073 | |
112f38a7 SR |
3074 | if (trace_flags & TRACE_ITER_LATENCY_FMT) |
3075 | iter->iter_flags |= TRACE_FILE_LAT_FMT; | |
3076 | ||
b04cc6b1 | 3077 | iter->cpu_file = cpu_file; |
b3806b43 | 3078 | iter->tr = &global_trace; |
d7350c3f | 3079 | mutex_init(&iter->mutex); |
b3806b43 SR |
3080 | filp->private_data = iter; |
3081 | ||
107bad8b SR |
3082 | if (iter->trace->pipe_open) |
3083 | iter->trace->pipe_open(iter); | |
107bad8b | 3084 | |
b444786f | 3085 | nonseekable_open(inode, filp); |
b04cc6b1 FW |
3086 | out: |
3087 | mutex_unlock(&trace_types_lock); | |
3088 | return ret; | |
d7350c3f FW |
3089 | |
3090 | fail: | |
3091 | kfree(iter->trace); | |
3092 | kfree(iter); | |
3093 | mutex_unlock(&trace_types_lock); | |
3094 | return ret; | |
b3806b43 SR |
3095 | } |
3096 | ||
3097 | static int tracing_release_pipe(struct inode *inode, struct file *file) | |
3098 | { | |
3099 | struct trace_iterator *iter = file->private_data; | |
3100 | ||
b04cc6b1 FW |
3101 | mutex_lock(&trace_types_lock); |
3102 | ||
29bf4a5e | 3103 | if (iter->trace->pipe_close) |
c521efd1 SR |
3104 | iter->trace->pipe_close(iter); |
3105 | ||
b04cc6b1 FW |
3106 | mutex_unlock(&trace_types_lock); |
3107 | ||
4462344e | 3108 | free_cpumask_var(iter->started); |
d7350c3f FW |
3109 | mutex_destroy(&iter->mutex); |
3110 | kfree(iter->trace); | |
b3806b43 | 3111 | kfree(iter); |
b3806b43 SR |
3112 | |
3113 | return 0; | |
3114 | } | |
3115 | ||
2a2cc8f7 SSP |
3116 | static unsigned int |
3117 | tracing_poll_pipe(struct file *filp, poll_table *poll_table) | |
3118 | { | |
3119 | struct trace_iterator *iter = filp->private_data; | |
3120 | ||
3121 | if (trace_flags & TRACE_ITER_BLOCK) { | |
3122 | /* | |
3123 | * Always select as readable when in blocking mode | |
3124 | */ | |
3125 | return POLLIN | POLLRDNORM; | |
afc2abc0 | 3126 | } else { |
2a2cc8f7 SSP |
3127 | if (!trace_empty(iter)) |
3128 | return POLLIN | POLLRDNORM; | |
3129 | poll_wait(filp, &trace_wait, poll_table); | |
3130 | if (!trace_empty(iter)) | |
3131 | return POLLIN | POLLRDNORM; | |
3132 | ||
3133 | return 0; | |
3134 | } | |
3135 | } | |
3136 | ||
6eaaa5d5 FW |
3137 | |
3138 | void default_wait_pipe(struct trace_iterator *iter) | |
3139 | { | |
3140 | DEFINE_WAIT(wait); | |
3141 | ||
3142 | prepare_to_wait(&trace_wait, &wait, TASK_INTERRUPTIBLE); | |
3143 | ||
3144 | if (trace_empty(iter)) | |
3145 | schedule(); | |
3146 | ||
3147 | finish_wait(&trace_wait, &wait); | |
3148 | } | |
3149 | ||
3150 | /* | |
3151 | * This is a make-shift waitqueue. | |
3152 | * A tracer might use this callback on some rare cases: | |
3153 | * | |
3154 | * 1) the current tracer might hold the runqueue lock when it wakes up | |
3155 | * a reader, hence a deadlock (sched, function, and function graph tracers) | |
3156 | * 2) the function tracers, trace all functions, we don't want | |
3157 | * the overhead of calling wake_up and friends | |
3158 | * (and tracing them too) | |
3159 | * | |
3160 | * Anyway, this is really very primitive wakeup. | |
3161 | */ | |
3162 | void poll_wait_pipe(struct trace_iterator *iter) | |
3163 | { | |
3164 | set_current_state(TASK_INTERRUPTIBLE); | |
3165 | /* sleep for 100 msecs, and try again. */ | |
3166 | schedule_timeout(HZ / 10); | |
3167 | } | |
3168 | ||
ff98781b EGM |
3169 | /* Must be called with trace_types_lock mutex held. */ |
3170 | static int tracing_wait_pipe(struct file *filp) | |
b3806b43 SR |
3171 | { |
3172 | struct trace_iterator *iter = filp->private_data; | |
b3806b43 | 3173 | |
b3806b43 | 3174 | while (trace_empty(iter)) { |
2dc8f095 | 3175 | |
107bad8b | 3176 | if ((filp->f_flags & O_NONBLOCK)) { |
ff98781b | 3177 | return -EAGAIN; |
107bad8b | 3178 | } |
2dc8f095 | 3179 | |
d7350c3f | 3180 | mutex_unlock(&iter->mutex); |
107bad8b | 3181 | |
6eaaa5d5 | 3182 | iter->trace->wait_pipe(iter); |
b3806b43 | 3183 | |
d7350c3f | 3184 | mutex_lock(&iter->mutex); |
107bad8b | 3185 | |
6eaaa5d5 | 3186 | if (signal_pending(current)) |
ff98781b | 3187 | return -EINTR; |
b3806b43 SR |
3188 | |
3189 | /* | |
3190 | * We block until we read something and tracing is disabled. | |
3191 | * We still block if tracing is disabled, but we have never | |
3192 | * read anything. This allows a user to cat this file, and | |
3193 | * then enable tracing. But after we have read something, | |
3194 | * we give an EOF when tracing is again disabled. | |
3195 | * | |
3196 | * iter->pos will be 0 if we haven't read anything. | |
3197 | */ | |
3198 | if (!tracer_enabled && iter->pos) | |
3199 | break; | |
b3806b43 SR |
3200 | } |
3201 | ||
ff98781b EGM |
3202 | return 1; |
3203 | } | |
3204 | ||
3205 | /* | |
3206 | * Consumer reader. | |
3207 | */ | |
3208 | static ssize_t | |
3209 | tracing_read_pipe(struct file *filp, char __user *ubuf, | |
3210 | size_t cnt, loff_t *ppos) | |
3211 | { | |
3212 | struct trace_iterator *iter = filp->private_data; | |
d7350c3f | 3213 | static struct tracer *old_tracer; |
ff98781b EGM |
3214 | ssize_t sret; |
3215 | ||
3216 | /* return any leftover data */ | |
3217 | sret = trace_seq_to_user(&iter->seq, ubuf, cnt); | |
3218 | if (sret != -EBUSY) | |
3219 | return sret; | |
3220 | ||
f9520750 | 3221 | trace_seq_init(&iter->seq); |
ff98781b | 3222 | |
d7350c3f | 3223 | /* copy the tracer to avoid using a global lock all around */ |
ff98781b | 3224 | mutex_lock(&trace_types_lock); |
d7350c3f FW |
3225 | if (unlikely(old_tracer != current_trace && current_trace)) { |
3226 | old_tracer = current_trace; | |
3227 | *iter->trace = *current_trace; | |
3228 | } | |
3229 | mutex_unlock(&trace_types_lock); | |
3230 | ||
3231 | /* | |
3232 | * Avoid more than one consumer on a single file descriptor | |
3233 | * This is just a matter of traces coherency, the ring buffer itself | |
3234 | * is protected. | |
3235 | */ | |
3236 | mutex_lock(&iter->mutex); | |
ff98781b EGM |
3237 | if (iter->trace->read) { |
3238 | sret = iter->trace->read(iter, filp, ubuf, cnt, ppos); | |
3239 | if (sret) | |
3240 | goto out; | |
3241 | } | |
3242 | ||
3243 | waitagain: | |
3244 | sret = tracing_wait_pipe(filp); | |
3245 | if (sret <= 0) | |
3246 | goto out; | |
3247 | ||
b3806b43 | 3248 | /* stop when tracing is finished */ |
ff98781b EGM |
3249 | if (trace_empty(iter)) { |
3250 | sret = 0; | |
107bad8b | 3251 | goto out; |
ff98781b | 3252 | } |
b3806b43 SR |
3253 | |
3254 | if (cnt >= PAGE_SIZE) | |
3255 | cnt = PAGE_SIZE - 1; | |
3256 | ||
53d0aa77 | 3257 | /* reset all but tr, trace, and overruns */ |
53d0aa77 SR |
3258 | memset(&iter->seq, 0, |
3259 | sizeof(struct trace_iterator) - | |
3260 | offsetof(struct trace_iterator, seq)); | |
4823ed7e | 3261 | iter->pos = -1; |
b3806b43 | 3262 | |
4f535968 | 3263 | trace_event_read_lock(); |
7e53bd42 | 3264 | trace_access_lock(iter->cpu_file); |
955b61e5 | 3265 | while (trace_find_next_entry_inc(iter) != NULL) { |
2c4f035f | 3266 | enum print_line_t ret; |
088b1e42 SR |
3267 | int len = iter->seq.len; |
3268 | ||
f9896bf3 | 3269 | ret = print_trace_line(iter); |
2c4f035f | 3270 | if (ret == TRACE_TYPE_PARTIAL_LINE) { |
088b1e42 SR |
3271 | /* don't print partial lines */ |
3272 | iter->seq.len = len; | |
b3806b43 | 3273 | break; |
088b1e42 | 3274 | } |
b91facc3 FW |
3275 | if (ret != TRACE_TYPE_NO_CONSUME) |
3276 | trace_consume(iter); | |
b3806b43 SR |
3277 | |
3278 | if (iter->seq.len >= cnt) | |
3279 | break; | |
ee5e51f5 JO |
3280 | |
3281 | /* | |
3282 | * Setting the full flag means we reached the trace_seq buffer | |
3283 | * size and we should leave by partial output condition above. | |
3284 | * One of the trace_seq_* functions is not used properly. | |
3285 | */ | |
3286 | WARN_ONCE(iter->seq.full, "full flag set for trace type %d", | |
3287 | iter->ent->type); | |
b3806b43 | 3288 | } |
7e53bd42 | 3289 | trace_access_unlock(iter->cpu_file); |
4f535968 | 3290 | trace_event_read_unlock(); |
b3806b43 | 3291 | |
b3806b43 | 3292 | /* Now copy what we have to the user */ |
6c6c2796 PP |
3293 | sret = trace_seq_to_user(&iter->seq, ubuf, cnt); |
3294 | if (iter->seq.readpos >= iter->seq.len) | |
f9520750 | 3295 | trace_seq_init(&iter->seq); |
9ff4b974 PP |
3296 | |
3297 | /* | |
25985edc | 3298 | * If there was nothing to send to user, in spite of consuming trace |
9ff4b974 PP |
3299 | * entries, go back to wait for more entries. |
3300 | */ | |
6c6c2796 | 3301 | if (sret == -EBUSY) |
9ff4b974 | 3302 | goto waitagain; |
b3806b43 | 3303 | |
107bad8b | 3304 | out: |
d7350c3f | 3305 | mutex_unlock(&iter->mutex); |
107bad8b | 3306 | |
6c6c2796 | 3307 | return sret; |
b3806b43 SR |
3308 | } |
3309 | ||
3c56819b EGM |
3310 | static void tracing_pipe_buf_release(struct pipe_inode_info *pipe, |
3311 | struct pipe_buffer *buf) | |
3312 | { | |
3313 | __free_page(buf->page); | |
3314 | } | |
3315 | ||
3316 | static void tracing_spd_release_pipe(struct splice_pipe_desc *spd, | |
3317 | unsigned int idx) | |
3318 | { | |
3319 | __free_page(spd->pages[idx]); | |
3320 | } | |
3321 | ||
28dfef8f | 3322 | static const struct pipe_buf_operations tracing_pipe_buf_ops = { |
34cd4998 SR |
3323 | .can_merge = 0, |
3324 | .map = generic_pipe_buf_map, | |
3325 | .unmap = generic_pipe_buf_unmap, | |
3326 | .confirm = generic_pipe_buf_confirm, | |
3327 | .release = tracing_pipe_buf_release, | |
3328 | .steal = generic_pipe_buf_steal, | |
3329 | .get = generic_pipe_buf_get, | |
3c56819b EGM |
3330 | }; |
3331 | ||
34cd4998 | 3332 | static size_t |
fa7c7f6e | 3333 | tracing_fill_pipe_page(size_t rem, struct trace_iterator *iter) |
34cd4998 SR |
3334 | { |
3335 | size_t count; | |
3336 | int ret; | |
3337 | ||
3338 | /* Seq buffer is page-sized, exactly what we need. */ | |
3339 | for (;;) { | |
3340 | count = iter->seq.len; | |
3341 | ret = print_trace_line(iter); | |
3342 | count = iter->seq.len - count; | |
3343 | if (rem < count) { | |
3344 | rem = 0; | |
3345 | iter->seq.len -= count; | |
3346 | break; | |
3347 | } | |
3348 | if (ret == TRACE_TYPE_PARTIAL_LINE) { | |
3349 | iter->seq.len -= count; | |
3350 | break; | |
3351 | } | |
3352 | ||
74e7ff8c LJ |
3353 | if (ret != TRACE_TYPE_NO_CONSUME) |
3354 | trace_consume(iter); | |
34cd4998 | 3355 | rem -= count; |
955b61e5 | 3356 | if (!trace_find_next_entry_inc(iter)) { |
34cd4998 SR |
3357 | rem = 0; |
3358 | iter->ent = NULL; | |
3359 | break; | |
3360 | } | |
3361 | } | |
3362 | ||
3363 | return rem; | |
3364 | } | |
3365 | ||
3c56819b EGM |
3366 | static ssize_t tracing_splice_read_pipe(struct file *filp, |
3367 | loff_t *ppos, | |
3368 | struct pipe_inode_info *pipe, | |
3369 | size_t len, | |
3370 | unsigned int flags) | |
3371 | { | |
35f3d14d JA |
3372 | struct page *pages_def[PIPE_DEF_BUFFERS]; |
3373 | struct partial_page partial_def[PIPE_DEF_BUFFERS]; | |
3c56819b EGM |
3374 | struct trace_iterator *iter = filp->private_data; |
3375 | struct splice_pipe_desc spd = { | |
35f3d14d JA |
3376 | .pages = pages_def, |
3377 | .partial = partial_def, | |
34cd4998 SR |
3378 | .nr_pages = 0, /* This gets updated below. */ |
3379 | .flags = flags, | |
3380 | .ops = &tracing_pipe_buf_ops, | |
3381 | .spd_release = tracing_spd_release_pipe, | |
3c56819b | 3382 | }; |
d7350c3f | 3383 | static struct tracer *old_tracer; |
3c56819b | 3384 | ssize_t ret; |
34cd4998 | 3385 | size_t rem; |
3c56819b EGM |
3386 | unsigned int i; |
3387 | ||
35f3d14d JA |
3388 | if (splice_grow_spd(pipe, &spd)) |
3389 | return -ENOMEM; | |
3390 | ||
d7350c3f | 3391 | /* copy the tracer to avoid using a global lock all around */ |
3c56819b | 3392 | mutex_lock(&trace_types_lock); |
d7350c3f FW |
3393 | if (unlikely(old_tracer != current_trace && current_trace)) { |
3394 | old_tracer = current_trace; | |
3395 | *iter->trace = *current_trace; | |
3396 | } | |
3397 | mutex_unlock(&trace_types_lock); | |
3398 | ||
3399 | mutex_lock(&iter->mutex); | |
3c56819b EGM |
3400 | |
3401 | if (iter->trace->splice_read) { | |
3402 | ret = iter->trace->splice_read(iter, filp, | |
3403 | ppos, pipe, len, flags); | |
3404 | if (ret) | |
34cd4998 | 3405 | goto out_err; |
3c56819b EGM |
3406 | } |
3407 | ||
3408 | ret = tracing_wait_pipe(filp); | |
3409 | if (ret <= 0) | |
34cd4998 | 3410 | goto out_err; |
3c56819b | 3411 | |
955b61e5 | 3412 | if (!iter->ent && !trace_find_next_entry_inc(iter)) { |
3c56819b | 3413 | ret = -EFAULT; |
34cd4998 | 3414 | goto out_err; |
3c56819b EGM |
3415 | } |
3416 | ||
4f535968 | 3417 | trace_event_read_lock(); |
7e53bd42 | 3418 | trace_access_lock(iter->cpu_file); |
4f535968 | 3419 | |
3c56819b | 3420 | /* Fill as many pages as possible. */ |
35f3d14d JA |
3421 | for (i = 0, rem = len; i < pipe->buffers && rem; i++) { |
3422 | spd.pages[i] = alloc_page(GFP_KERNEL); | |
3423 | if (!spd.pages[i]) | |
34cd4998 | 3424 | break; |
3c56819b | 3425 | |
fa7c7f6e | 3426 | rem = tracing_fill_pipe_page(rem, iter); |
3c56819b EGM |
3427 | |
3428 | /* Copy the data into the page, so we can start over. */ | |
3429 | ret = trace_seq_to_buffer(&iter->seq, | |
35f3d14d | 3430 | page_address(spd.pages[i]), |
3c56819b EGM |
3431 | iter->seq.len); |
3432 | if (ret < 0) { | |
35f3d14d | 3433 | __free_page(spd.pages[i]); |
3c56819b EGM |
3434 | break; |
3435 | } | |
35f3d14d JA |
3436 | spd.partial[i].offset = 0; |
3437 | spd.partial[i].len = iter->seq.len; | |
3c56819b | 3438 | |
f9520750 | 3439 | trace_seq_init(&iter->seq); |
3c56819b EGM |
3440 | } |
3441 | ||
7e53bd42 | 3442 | trace_access_unlock(iter->cpu_file); |
4f535968 | 3443 | trace_event_read_unlock(); |
d7350c3f | 3444 | mutex_unlock(&iter->mutex); |
3c56819b EGM |
3445 | |
3446 | spd.nr_pages = i; | |
3447 | ||
35f3d14d JA |
3448 | ret = splice_to_pipe(pipe, &spd); |
3449 | out: | |
3450 | splice_shrink_spd(pipe, &spd); | |
3451 | return ret; | |
3c56819b | 3452 | |
34cd4998 | 3453 | out_err: |
d7350c3f | 3454 | mutex_unlock(&iter->mutex); |
35f3d14d | 3455 | goto out; |
3c56819b EGM |
3456 | } |
3457 | ||
a98a3c3f SR |
3458 | static ssize_t |
3459 | tracing_entries_read(struct file *filp, char __user *ubuf, | |
3460 | size_t cnt, loff_t *ppos) | |
3461 | { | |
3462 | struct trace_array *tr = filp->private_data; | |
db526ca3 | 3463 | char buf[96]; |
a98a3c3f SR |
3464 | int r; |
3465 | ||
db526ca3 SR |
3466 | mutex_lock(&trace_types_lock); |
3467 | if (!ring_buffer_expanded) | |
3468 | r = sprintf(buf, "%lu (expanded: %lu)\n", | |
3469 | tr->entries >> 10, | |
3470 | trace_buf_size >> 10); | |
3471 | else | |
3472 | r = sprintf(buf, "%lu\n", tr->entries >> 10); | |
3473 | mutex_unlock(&trace_types_lock); | |
3474 | ||
a98a3c3f SR |
3475 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, r); |
3476 | } | |
3477 | ||
3478 | static ssize_t | |
3479 | tracing_entries_write(struct file *filp, const char __user *ubuf, | |
3480 | size_t cnt, loff_t *ppos) | |
3481 | { | |
3482 | unsigned long val; | |
4f271a2a | 3483 | int ret; |
a98a3c3f | 3484 | |
22fe9b54 PH |
3485 | ret = kstrtoul_from_user(ubuf, cnt, 10, &val); |
3486 | if (ret) | |
c6caeeb1 | 3487 | return ret; |
a98a3c3f SR |
3488 | |
3489 | /* must have at least 1 entry */ | |
3490 | if (!val) | |
3491 | return -EINVAL; | |
3492 | ||
1696b2b0 SR |
3493 | /* value is in KB */ |
3494 | val <<= 10; | |
3495 | ||
4f271a2a VN |
3496 | ret = tracing_resize_ring_buffer(val); |
3497 | if (ret < 0) | |
3498 | return ret; | |
a98a3c3f | 3499 | |
cf8517cf | 3500 | *ppos += cnt; |
a98a3c3f | 3501 | |
4f271a2a VN |
3502 | return cnt; |
3503 | } | |
bf5e6519 | 3504 | |
4f271a2a VN |
3505 | static ssize_t |
3506 | tracing_free_buffer_write(struct file *filp, const char __user *ubuf, | |
3507 | size_t cnt, loff_t *ppos) | |
3508 | { | |
3509 | /* | |
3510 | * There is no need to read what the user has written, this function | |
3511 | * is just to make sure that there is no error when "echo" is used | |
3512 | */ | |
3513 | ||
3514 | *ppos += cnt; | |
a98a3c3f SR |
3515 | |
3516 | return cnt; | |
3517 | } | |
3518 | ||
4f271a2a VN |
3519 | static int |
3520 | tracing_free_buffer_release(struct inode *inode, struct file *filp) | |
3521 | { | |
cf30cf67 SR |
3522 | /* disable tracing ? */ |
3523 | if (trace_flags & TRACE_ITER_STOP_ON_FREE) | |
3524 | tracing_off(); | |
4f271a2a VN |
3525 | /* resize the ring buffer to 0 */ |
3526 | tracing_resize_ring_buffer(0); | |
3527 | ||
3528 | return 0; | |
3529 | } | |
3530 | ||
f2942487 CE |
3531 | static int mark_printk(const char *fmt, ...) |
3532 | { | |
3533 | int ret; | |
3534 | va_list args; | |
3535 | va_start(args, fmt); | |
3536 | ret = trace_vprintk(0, fmt, args); | |
3537 | va_end(args); | |
3538 | return ret; | |
3539 | } | |
3540 | ||
5bf9a1ee PP |
3541 | static ssize_t |
3542 | tracing_mark_write(struct file *filp, const char __user *ubuf, | |
3543 | size_t cnt, loff_t *fpos) | |
3544 | { | |
3545 | char *buf; | |
1aa54bca | 3546 | size_t written; |
5bf9a1ee | 3547 | |
c76f0694 | 3548 | if (tracing_disabled) |
5bf9a1ee PP |
3549 | return -EINVAL; |
3550 | ||
3551 | if (cnt > TRACE_BUF_SIZE) | |
3552 | cnt = TRACE_BUF_SIZE; | |
3553 | ||
c13d2f7c | 3554 | buf = kmalloc(cnt + 2, GFP_KERNEL); |
5bf9a1ee PP |
3555 | if (buf == NULL) |
3556 | return -ENOMEM; | |
3557 | ||
3558 | if (copy_from_user(buf, ubuf, cnt)) { | |
3559 | kfree(buf); | |
3560 | return -EFAULT; | |
3561 | } | |
c13d2f7c CE |
3562 | if (buf[cnt-1] != '\n') { |
3563 | buf[cnt] = '\n'; | |
3564 | buf[cnt+1] = '\0'; | |
3565 | } else | |
3566 | buf[cnt] = '\0'; | |
5bf9a1ee | 3567 | |
1aa54bca | 3568 | written = mark_printk("%s", buf); |
5bf9a1ee | 3569 | kfree(buf); |
1aa54bca | 3570 | *fpos += written; |
5bf9a1ee | 3571 | |
1aa54bca MS |
3572 | /* don't tell userspace we wrote more - it might confuse them */ |
3573 | if (written > cnt) | |
3574 | written = cnt; | |
3575 | ||
3576 | return written; | |
5bf9a1ee PP |
3577 | } |
3578 | ||
13f16d20 | 3579 | static int tracing_clock_show(struct seq_file *m, void *v) |
5079f326 | 3580 | { |
5079f326 Z |
3581 | int i; |
3582 | ||
3583 | for (i = 0; i < ARRAY_SIZE(trace_clocks); i++) | |
13f16d20 | 3584 | seq_printf(m, |
5079f326 Z |
3585 | "%s%s%s%s", i ? " " : "", |
3586 | i == trace_clock_id ? "[" : "", trace_clocks[i].name, | |
3587 | i == trace_clock_id ? "]" : ""); | |
13f16d20 | 3588 | seq_putc(m, '\n'); |
5079f326 | 3589 | |
13f16d20 | 3590 | return 0; |
5079f326 Z |
3591 | } |
3592 | ||
3593 | static ssize_t tracing_clock_write(struct file *filp, const char __user *ubuf, | |
3594 | size_t cnt, loff_t *fpos) | |
3595 | { | |
3596 | char buf[64]; | |
3597 | const char *clockstr; | |
3598 | int i; | |
3599 | ||
3600 | if (cnt >= sizeof(buf)) | |
3601 | return -EINVAL; | |
3602 | ||
3603 | if (copy_from_user(&buf, ubuf, cnt)) | |
3604 | return -EFAULT; | |
3605 | ||
3606 | buf[cnt] = 0; | |
3607 | ||
3608 | clockstr = strstrip(buf); | |
3609 | ||
3610 | for (i = 0; i < ARRAY_SIZE(trace_clocks); i++) { | |
3611 | if (strcmp(trace_clocks[i].name, clockstr) == 0) | |
3612 | break; | |
3613 | } | |
3614 | if (i == ARRAY_SIZE(trace_clocks)) | |
3615 | return -EINVAL; | |
3616 | ||
3617 | trace_clock_id = i; | |
3618 | ||
3619 | mutex_lock(&trace_types_lock); | |
3620 | ||
3621 | ring_buffer_set_clock(global_trace.buffer, trace_clocks[i].func); | |
3622 | if (max_tr.buffer) | |
3623 | ring_buffer_set_clock(max_tr.buffer, trace_clocks[i].func); | |
3624 | ||
3625 | mutex_unlock(&trace_types_lock); | |
3626 | ||
3627 | *fpos += cnt; | |
3628 | ||
3629 | return cnt; | |
3630 | } | |
3631 | ||
13f16d20 LZ |
3632 | static int tracing_clock_open(struct inode *inode, struct file *file) |
3633 | { | |
3634 | if (tracing_disabled) | |
3635 | return -ENODEV; | |
3636 | return single_open(file, tracing_clock_show, NULL); | |
3637 | } | |
3638 | ||
5e2336a0 | 3639 | static const struct file_operations tracing_max_lat_fops = { |
4bf39a94 IM |
3640 | .open = tracing_open_generic, |
3641 | .read = tracing_max_lat_read, | |
3642 | .write = tracing_max_lat_write, | |
b444786f | 3643 | .llseek = generic_file_llseek, |
bc0c38d1 SR |
3644 | }; |
3645 | ||
5e2336a0 | 3646 | static const struct file_operations tracing_ctrl_fops = { |
4bf39a94 IM |
3647 | .open = tracing_open_generic, |
3648 | .read = tracing_ctrl_read, | |
3649 | .write = tracing_ctrl_write, | |
b444786f | 3650 | .llseek = generic_file_llseek, |
bc0c38d1 SR |
3651 | }; |
3652 | ||
5e2336a0 | 3653 | static const struct file_operations set_tracer_fops = { |
4bf39a94 IM |
3654 | .open = tracing_open_generic, |
3655 | .read = tracing_set_trace_read, | |
3656 | .write = tracing_set_trace_write, | |
b444786f | 3657 | .llseek = generic_file_llseek, |
bc0c38d1 SR |
3658 | }; |
3659 | ||
5e2336a0 | 3660 | static const struct file_operations tracing_pipe_fops = { |
4bf39a94 | 3661 | .open = tracing_open_pipe, |
2a2cc8f7 | 3662 | .poll = tracing_poll_pipe, |
4bf39a94 | 3663 | .read = tracing_read_pipe, |
3c56819b | 3664 | .splice_read = tracing_splice_read_pipe, |
4bf39a94 | 3665 | .release = tracing_release_pipe, |
b444786f | 3666 | .llseek = no_llseek, |
b3806b43 SR |
3667 | }; |
3668 | ||
5e2336a0 | 3669 | static const struct file_operations tracing_entries_fops = { |
a98a3c3f SR |
3670 | .open = tracing_open_generic, |
3671 | .read = tracing_entries_read, | |
3672 | .write = tracing_entries_write, | |
b444786f | 3673 | .llseek = generic_file_llseek, |
a98a3c3f SR |
3674 | }; |
3675 | ||
4f271a2a VN |
3676 | static const struct file_operations tracing_free_buffer_fops = { |
3677 | .write = tracing_free_buffer_write, | |
3678 | .release = tracing_free_buffer_release, | |
3679 | }; | |
3680 | ||
5e2336a0 | 3681 | static const struct file_operations tracing_mark_fops = { |
43a15386 | 3682 | .open = tracing_open_generic, |
5bf9a1ee | 3683 | .write = tracing_mark_write, |
b444786f | 3684 | .llseek = generic_file_llseek, |
5bf9a1ee PP |
3685 | }; |
3686 | ||
5079f326 | 3687 | static const struct file_operations trace_clock_fops = { |
13f16d20 LZ |
3688 | .open = tracing_clock_open, |
3689 | .read = seq_read, | |
3690 | .llseek = seq_lseek, | |
3691 | .release = single_release, | |
5079f326 Z |
3692 | .write = tracing_clock_write, |
3693 | }; | |
3694 | ||
2cadf913 SR |
3695 | struct ftrace_buffer_info { |
3696 | struct trace_array *tr; | |
3697 | void *spare; | |
3698 | int cpu; | |
3699 | unsigned int read; | |
3700 | }; | |
3701 | ||
3702 | static int tracing_buffers_open(struct inode *inode, struct file *filp) | |
3703 | { | |
3704 | int cpu = (int)(long)inode->i_private; | |
3705 | struct ftrace_buffer_info *info; | |
3706 | ||
3707 | if (tracing_disabled) | |
3708 | return -ENODEV; | |
3709 | ||
3710 | info = kzalloc(sizeof(*info), GFP_KERNEL); | |
3711 | if (!info) | |
3712 | return -ENOMEM; | |
3713 | ||
3714 | info->tr = &global_trace; | |
3715 | info->cpu = cpu; | |
ddd538f3 | 3716 | info->spare = NULL; |
2cadf913 SR |
3717 | /* Force reading ring buffer for first read */ |
3718 | info->read = (unsigned int)-1; | |
2cadf913 SR |
3719 | |
3720 | filp->private_data = info; | |
3721 | ||
d1e7e02f | 3722 | return nonseekable_open(inode, filp); |
2cadf913 SR |
3723 | } |
3724 | ||
3725 | static ssize_t | |
3726 | tracing_buffers_read(struct file *filp, char __user *ubuf, | |
3727 | size_t count, loff_t *ppos) | |
3728 | { | |
3729 | struct ftrace_buffer_info *info = filp->private_data; | |
2cadf913 SR |
3730 | ssize_t ret; |
3731 | size_t size; | |
3732 | ||
2dc5d12b SR |
3733 | if (!count) |
3734 | return 0; | |
3735 | ||
ddd538f3 | 3736 | if (!info->spare) |
7ea59064 | 3737 | info->spare = ring_buffer_alloc_read_page(info->tr->buffer, info->cpu); |
ddd538f3 LJ |
3738 | if (!info->spare) |
3739 | return -ENOMEM; | |
3740 | ||
2cadf913 SR |
3741 | /* Do we have previous read data to read? */ |
3742 | if (info->read < PAGE_SIZE) | |
3743 | goto read; | |
3744 | ||
3745 | info->read = 0; | |
3746 | ||
7e53bd42 | 3747 | trace_access_lock(info->cpu); |
2cadf913 SR |
3748 | ret = ring_buffer_read_page(info->tr->buffer, |
3749 | &info->spare, | |
3750 | count, | |
3751 | info->cpu, 0); | |
7e53bd42 | 3752 | trace_access_unlock(info->cpu); |
2cadf913 SR |
3753 | if (ret < 0) |
3754 | return 0; | |
3755 | ||
2cadf913 SR |
3756 | read: |
3757 | size = PAGE_SIZE - info->read; | |
3758 | if (size > count) | |
3759 | size = count; | |
3760 | ||
3761 | ret = copy_to_user(ubuf, info->spare + info->read, size); | |
2dc5d12b | 3762 | if (ret == size) |
2cadf913 | 3763 | return -EFAULT; |
2dc5d12b SR |
3764 | size -= ret; |
3765 | ||
2cadf913 SR |
3766 | *ppos += size; |
3767 | info->read += size; | |
3768 | ||
3769 | return size; | |
3770 | } | |
3771 | ||
3772 | static int tracing_buffers_release(struct inode *inode, struct file *file) | |
3773 | { | |
3774 | struct ftrace_buffer_info *info = file->private_data; | |
3775 | ||
ddd538f3 LJ |
3776 | if (info->spare) |
3777 | ring_buffer_free_read_page(info->tr->buffer, info->spare); | |
2cadf913 SR |
3778 | kfree(info); |
3779 | ||
3780 | return 0; | |
3781 | } | |
3782 | ||
3783 | struct buffer_ref { | |
3784 | struct ring_buffer *buffer; | |
3785 | void *page; | |
3786 | int ref; | |
3787 | }; | |
3788 | ||
3789 | static void buffer_pipe_buf_release(struct pipe_inode_info *pipe, | |
3790 | struct pipe_buffer *buf) | |
3791 | { | |
3792 | struct buffer_ref *ref = (struct buffer_ref *)buf->private; | |
3793 | ||
3794 | if (--ref->ref) | |
3795 | return; | |
3796 | ||
3797 | ring_buffer_free_read_page(ref->buffer, ref->page); | |
3798 | kfree(ref); | |
3799 | buf->private = 0; | |
3800 | } | |
3801 | ||
3802 | static int buffer_pipe_buf_steal(struct pipe_inode_info *pipe, | |
3803 | struct pipe_buffer *buf) | |
3804 | { | |
3805 | return 1; | |
3806 | } | |
3807 | ||
3808 | static void buffer_pipe_buf_get(struct pipe_inode_info *pipe, | |
3809 | struct pipe_buffer *buf) | |
3810 | { | |
3811 | struct buffer_ref *ref = (struct buffer_ref *)buf->private; | |
3812 | ||
3813 | ref->ref++; | |
3814 | } | |
3815 | ||
3816 | /* Pipe buffer operations for a buffer. */ | |
28dfef8f | 3817 | static const struct pipe_buf_operations buffer_pipe_buf_ops = { |
2cadf913 SR |
3818 | .can_merge = 0, |
3819 | .map = generic_pipe_buf_map, | |
3820 | .unmap = generic_pipe_buf_unmap, | |
3821 | .confirm = generic_pipe_buf_confirm, | |
3822 | .release = buffer_pipe_buf_release, | |
3823 | .steal = buffer_pipe_buf_steal, | |
3824 | .get = buffer_pipe_buf_get, | |
3825 | }; | |
3826 | ||
3827 | /* | |
3828 | * Callback from splice_to_pipe(), if we need to release some pages | |
3829 | * at the end of the spd in case we error'ed out in filling the pipe. | |
3830 | */ | |
3831 | static void buffer_spd_release(struct splice_pipe_desc *spd, unsigned int i) | |
3832 | { | |
3833 | struct buffer_ref *ref = | |
3834 | (struct buffer_ref *)spd->partial[i].private; | |
3835 | ||
3836 | if (--ref->ref) | |
3837 | return; | |
3838 | ||
3839 | ring_buffer_free_read_page(ref->buffer, ref->page); | |
3840 | kfree(ref); | |
3841 | spd->partial[i].private = 0; | |
3842 | } | |
3843 | ||
3844 | static ssize_t | |
3845 | tracing_buffers_splice_read(struct file *file, loff_t *ppos, | |
3846 | struct pipe_inode_info *pipe, size_t len, | |
3847 | unsigned int flags) | |
3848 | { | |
3849 | struct ftrace_buffer_info *info = file->private_data; | |
35f3d14d JA |
3850 | struct partial_page partial_def[PIPE_DEF_BUFFERS]; |
3851 | struct page *pages_def[PIPE_DEF_BUFFERS]; | |
2cadf913 | 3852 | struct splice_pipe_desc spd = { |
35f3d14d JA |
3853 | .pages = pages_def, |
3854 | .partial = partial_def, | |
2cadf913 SR |
3855 | .flags = flags, |
3856 | .ops = &buffer_pipe_buf_ops, | |
3857 | .spd_release = buffer_spd_release, | |
3858 | }; | |
3859 | struct buffer_ref *ref; | |
93459c6c | 3860 | int entries, size, i; |
2cadf913 SR |
3861 | size_t ret; |
3862 | ||
35f3d14d JA |
3863 | if (splice_grow_spd(pipe, &spd)) |
3864 | return -ENOMEM; | |
3865 | ||
93cfb3c9 LJ |
3866 | if (*ppos & (PAGE_SIZE - 1)) { |
3867 | WARN_ONCE(1, "Ftrace: previous read must page-align\n"); | |
35f3d14d JA |
3868 | ret = -EINVAL; |
3869 | goto out; | |
93cfb3c9 LJ |
3870 | } |
3871 | ||
3872 | if (len & (PAGE_SIZE - 1)) { | |
3873 | WARN_ONCE(1, "Ftrace: splice_read should page-align\n"); | |
35f3d14d JA |
3874 | if (len < PAGE_SIZE) { |
3875 | ret = -EINVAL; | |
3876 | goto out; | |
3877 | } | |
93cfb3c9 LJ |
3878 | len &= PAGE_MASK; |
3879 | } | |
3880 | ||
7e53bd42 | 3881 | trace_access_lock(info->cpu); |
93459c6c SR |
3882 | entries = ring_buffer_entries_cpu(info->tr->buffer, info->cpu); |
3883 | ||
35f3d14d | 3884 | for (i = 0; i < pipe->buffers && len && entries; i++, len -= PAGE_SIZE) { |
2cadf913 SR |
3885 | struct page *page; |
3886 | int r; | |
3887 | ||
3888 | ref = kzalloc(sizeof(*ref), GFP_KERNEL); | |
3889 | if (!ref) | |
3890 | break; | |
3891 | ||
7267fa68 | 3892 | ref->ref = 1; |
2cadf913 | 3893 | ref->buffer = info->tr->buffer; |
7ea59064 | 3894 | ref->page = ring_buffer_alloc_read_page(ref->buffer, info->cpu); |
2cadf913 SR |
3895 | if (!ref->page) { |
3896 | kfree(ref); | |
3897 | break; | |
3898 | } | |
3899 | ||
3900 | r = ring_buffer_read_page(ref->buffer, &ref->page, | |
f2957f1f | 3901 | len, info->cpu, 1); |
2cadf913 | 3902 | if (r < 0) { |
7ea59064 | 3903 | ring_buffer_free_read_page(ref->buffer, ref->page); |
2cadf913 SR |
3904 | kfree(ref); |
3905 | break; | |
3906 | } | |
3907 | ||
3908 | /* | |
3909 | * zero out any left over data, this is going to | |
3910 | * user land. | |
3911 | */ | |
3912 | size = ring_buffer_page_len(ref->page); | |
3913 | if (size < PAGE_SIZE) | |
3914 | memset(ref->page + size, 0, PAGE_SIZE - size); | |
3915 | ||
3916 | page = virt_to_page(ref->page); | |
3917 | ||
3918 | spd.pages[i] = page; | |
3919 | spd.partial[i].len = PAGE_SIZE; | |
3920 | spd.partial[i].offset = 0; | |
3921 | spd.partial[i].private = (unsigned long)ref; | |
3922 | spd.nr_pages++; | |
93cfb3c9 | 3923 | *ppos += PAGE_SIZE; |
93459c6c SR |
3924 | |
3925 | entries = ring_buffer_entries_cpu(info->tr->buffer, info->cpu); | |
2cadf913 SR |
3926 | } |
3927 | ||
7e53bd42 | 3928 | trace_access_unlock(info->cpu); |
2cadf913 SR |
3929 | spd.nr_pages = i; |
3930 | ||
3931 | /* did we read anything? */ | |
3932 | if (!spd.nr_pages) { | |
3933 | if (flags & SPLICE_F_NONBLOCK) | |
3934 | ret = -EAGAIN; | |
3935 | else | |
3936 | ret = 0; | |
3937 | /* TODO: block */ | |
35f3d14d | 3938 | goto out; |
2cadf913 SR |
3939 | } |
3940 | ||
3941 | ret = splice_to_pipe(pipe, &spd); | |
35f3d14d JA |
3942 | splice_shrink_spd(pipe, &spd); |
3943 | out: | |
2cadf913 SR |
3944 | return ret; |
3945 | } | |
3946 | ||
3947 | static const struct file_operations tracing_buffers_fops = { | |
3948 | .open = tracing_buffers_open, | |
3949 | .read = tracing_buffers_read, | |
3950 | .release = tracing_buffers_release, | |
3951 | .splice_read = tracing_buffers_splice_read, | |
3952 | .llseek = no_llseek, | |
3953 | }; | |
3954 | ||
c8d77183 SR |
3955 | static ssize_t |
3956 | tracing_stats_read(struct file *filp, char __user *ubuf, | |
3957 | size_t count, loff_t *ppos) | |
3958 | { | |
3959 | unsigned long cpu = (unsigned long)filp->private_data; | |
3960 | struct trace_array *tr = &global_trace; | |
3961 | struct trace_seq *s; | |
3962 | unsigned long cnt; | |
3963 | ||
e4f2d10f | 3964 | s = kmalloc(sizeof(*s), GFP_KERNEL); |
c8d77183 | 3965 | if (!s) |
a646365c | 3966 | return -ENOMEM; |
c8d77183 SR |
3967 | |
3968 | trace_seq_init(s); | |
3969 | ||
3970 | cnt = ring_buffer_entries_cpu(tr->buffer, cpu); | |
3971 | trace_seq_printf(s, "entries: %ld\n", cnt); | |
3972 | ||
3973 | cnt = ring_buffer_overrun_cpu(tr->buffer, cpu); | |
3974 | trace_seq_printf(s, "overrun: %ld\n", cnt); | |
3975 | ||
3976 | cnt = ring_buffer_commit_overrun_cpu(tr->buffer, cpu); | |
3977 | trace_seq_printf(s, "commit overrun: %ld\n", cnt); | |
3978 | ||
c8d77183 SR |
3979 | count = simple_read_from_buffer(ubuf, count, ppos, s->buffer, s->len); |
3980 | ||
3981 | kfree(s); | |
3982 | ||
3983 | return count; | |
3984 | } | |
3985 | ||
3986 | static const struct file_operations tracing_stats_fops = { | |
3987 | .open = tracing_open_generic, | |
3988 | .read = tracing_stats_read, | |
b444786f | 3989 | .llseek = generic_file_llseek, |
c8d77183 SR |
3990 | }; |
3991 | ||
bc0c38d1 SR |
3992 | #ifdef CONFIG_DYNAMIC_FTRACE |
3993 | ||
b807c3d0 SR |
3994 | int __weak ftrace_arch_read_dyn_info(char *buf, int size) |
3995 | { | |
3996 | return 0; | |
3997 | } | |
3998 | ||
bc0c38d1 | 3999 | static ssize_t |
b807c3d0 | 4000 | tracing_read_dyn_info(struct file *filp, char __user *ubuf, |
bc0c38d1 SR |
4001 | size_t cnt, loff_t *ppos) |
4002 | { | |
a26a2a27 SR |
4003 | static char ftrace_dyn_info_buffer[1024]; |
4004 | static DEFINE_MUTEX(dyn_info_mutex); | |
bc0c38d1 | 4005 | unsigned long *p = filp->private_data; |
b807c3d0 | 4006 | char *buf = ftrace_dyn_info_buffer; |
a26a2a27 | 4007 | int size = ARRAY_SIZE(ftrace_dyn_info_buffer); |
bc0c38d1 SR |
4008 | int r; |
4009 | ||
b807c3d0 SR |
4010 | mutex_lock(&dyn_info_mutex); |
4011 | r = sprintf(buf, "%ld ", *p); | |
4bf39a94 | 4012 | |
a26a2a27 | 4013 | r += ftrace_arch_read_dyn_info(buf+r, (size-1)-r); |
b807c3d0 SR |
4014 | buf[r++] = '\n'; |
4015 | ||
4016 | r = simple_read_from_buffer(ubuf, cnt, ppos, buf, r); | |
4017 | ||
4018 | mutex_unlock(&dyn_info_mutex); | |
4019 | ||
4020 | return r; | |
bc0c38d1 SR |
4021 | } |
4022 | ||
5e2336a0 | 4023 | static const struct file_operations tracing_dyn_info_fops = { |
4bf39a94 | 4024 | .open = tracing_open_generic, |
b807c3d0 | 4025 | .read = tracing_read_dyn_info, |
b444786f | 4026 | .llseek = generic_file_llseek, |
bc0c38d1 SR |
4027 | }; |
4028 | #endif | |
4029 | ||
4030 | static struct dentry *d_tracer; | |
4031 | ||
4032 | struct dentry *tracing_init_dentry(void) | |
4033 | { | |
4034 | static int once; | |
4035 | ||
4036 | if (d_tracer) | |
4037 | return d_tracer; | |
4038 | ||
3e1f60b8 FW |
4039 | if (!debugfs_initialized()) |
4040 | return NULL; | |
4041 | ||
bc0c38d1 SR |
4042 | d_tracer = debugfs_create_dir("tracing", NULL); |
4043 | ||
4044 | if (!d_tracer && !once) { | |
4045 | once = 1; | |
4046 | pr_warning("Could not create debugfs directory 'tracing'\n"); | |
4047 | return NULL; | |
4048 | } | |
4049 | ||
4050 | return d_tracer; | |
4051 | } | |
4052 | ||
b04cc6b1 FW |
4053 | static struct dentry *d_percpu; |
4054 | ||
4055 | struct dentry *tracing_dentry_percpu(void) | |
4056 | { | |
4057 | static int once; | |
4058 | struct dentry *d_tracer; | |
4059 | ||
4060 | if (d_percpu) | |
4061 | return d_percpu; | |
4062 | ||
4063 | d_tracer = tracing_init_dentry(); | |
4064 | ||
4065 | if (!d_tracer) | |
4066 | return NULL; | |
4067 | ||
4068 | d_percpu = debugfs_create_dir("per_cpu", d_tracer); | |
4069 | ||
4070 | if (!d_percpu && !once) { | |
4071 | once = 1; | |
4072 | pr_warning("Could not create debugfs directory 'per_cpu'\n"); | |
4073 | return NULL; | |
4074 | } | |
4075 | ||
4076 | return d_percpu; | |
4077 | } | |
4078 | ||
4079 | static void tracing_init_debugfs_percpu(long cpu) | |
4080 | { | |
4081 | struct dentry *d_percpu = tracing_dentry_percpu(); | |
5452af66 | 4082 | struct dentry *d_cpu; |
dd49a38c | 4083 | char cpu_dir[30]; /* 30 characters should be more than enough */ |
b04cc6b1 | 4084 | |
dd49a38c | 4085 | snprintf(cpu_dir, 30, "cpu%ld", cpu); |
8656e7a2 FW |
4086 | d_cpu = debugfs_create_dir(cpu_dir, d_percpu); |
4087 | if (!d_cpu) { | |
4088 | pr_warning("Could not create debugfs '%s' entry\n", cpu_dir); | |
4089 | return; | |
4090 | } | |
b04cc6b1 | 4091 | |
8656e7a2 | 4092 | /* per cpu trace_pipe */ |
5452af66 FW |
4093 | trace_create_file("trace_pipe", 0444, d_cpu, |
4094 | (void *) cpu, &tracing_pipe_fops); | |
b04cc6b1 FW |
4095 | |
4096 | /* per cpu trace */ | |
5452af66 FW |
4097 | trace_create_file("trace", 0644, d_cpu, |
4098 | (void *) cpu, &tracing_fops); | |
7f96f93f | 4099 | |
5452af66 FW |
4100 | trace_create_file("trace_pipe_raw", 0444, d_cpu, |
4101 | (void *) cpu, &tracing_buffers_fops); | |
7f96f93f | 4102 | |
c8d77183 SR |
4103 | trace_create_file("stats", 0444, d_cpu, |
4104 | (void *) cpu, &tracing_stats_fops); | |
b04cc6b1 FW |
4105 | } |
4106 | ||
60a11774 SR |
4107 | #ifdef CONFIG_FTRACE_SELFTEST |
4108 | /* Let selftest have access to static functions in this file */ | |
4109 | #include "trace_selftest.c" | |
4110 | #endif | |
4111 | ||
577b785f SR |
4112 | struct trace_option_dentry { |
4113 | struct tracer_opt *opt; | |
4114 | struct tracer_flags *flags; | |
4115 | struct dentry *entry; | |
4116 | }; | |
4117 | ||
4118 | static ssize_t | |
4119 | trace_options_read(struct file *filp, char __user *ubuf, size_t cnt, | |
4120 | loff_t *ppos) | |
4121 | { | |
4122 | struct trace_option_dentry *topt = filp->private_data; | |
4123 | char *buf; | |
4124 | ||
4125 | if (topt->flags->val & topt->opt->bit) | |
4126 | buf = "1\n"; | |
4127 | else | |
4128 | buf = "0\n"; | |
4129 | ||
4130 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, 2); | |
4131 | } | |
4132 | ||
4133 | static ssize_t | |
4134 | trace_options_write(struct file *filp, const char __user *ubuf, size_t cnt, | |
4135 | loff_t *ppos) | |
4136 | { | |
4137 | struct trace_option_dentry *topt = filp->private_data; | |
4138 | unsigned long val; | |
577b785f SR |
4139 | int ret; |
4140 | ||
22fe9b54 PH |
4141 | ret = kstrtoul_from_user(ubuf, cnt, 10, &val); |
4142 | if (ret) | |
577b785f SR |
4143 | return ret; |
4144 | ||
8d18eaaf LZ |
4145 | if (val != 0 && val != 1) |
4146 | return -EINVAL; | |
577b785f | 4147 | |
8d18eaaf | 4148 | if (!!(topt->flags->val & topt->opt->bit) != val) { |
577b785f | 4149 | mutex_lock(&trace_types_lock); |
8d18eaaf | 4150 | ret = __set_tracer_option(current_trace, topt->flags, |
c757bea9 | 4151 | topt->opt, !val); |
577b785f SR |
4152 | mutex_unlock(&trace_types_lock); |
4153 | if (ret) | |
4154 | return ret; | |
577b785f SR |
4155 | } |
4156 | ||
4157 | *ppos += cnt; | |
4158 | ||
4159 | return cnt; | |
4160 | } | |
4161 | ||
4162 | ||
4163 | static const struct file_operations trace_options_fops = { | |
4164 | .open = tracing_open_generic, | |
4165 | .read = trace_options_read, | |
4166 | .write = trace_options_write, | |
b444786f | 4167 | .llseek = generic_file_llseek, |
577b785f SR |
4168 | }; |
4169 | ||
a8259075 SR |
4170 | static ssize_t |
4171 | trace_options_core_read(struct file *filp, char __user *ubuf, size_t cnt, | |
4172 | loff_t *ppos) | |
4173 | { | |
4174 | long index = (long)filp->private_data; | |
4175 | char *buf; | |
4176 | ||
4177 | if (trace_flags & (1 << index)) | |
4178 | buf = "1\n"; | |
4179 | else | |
4180 | buf = "0\n"; | |
4181 | ||
4182 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, 2); | |
4183 | } | |
4184 | ||
4185 | static ssize_t | |
4186 | trace_options_core_write(struct file *filp, const char __user *ubuf, size_t cnt, | |
4187 | loff_t *ppos) | |
4188 | { | |
4189 | long index = (long)filp->private_data; | |
a8259075 SR |
4190 | unsigned long val; |
4191 | int ret; | |
4192 | ||
22fe9b54 PH |
4193 | ret = kstrtoul_from_user(ubuf, cnt, 10, &val); |
4194 | if (ret) | |
a8259075 SR |
4195 | return ret; |
4196 | ||
f2d84b65 | 4197 | if (val != 0 && val != 1) |
a8259075 | 4198 | return -EINVAL; |
f2d84b65 | 4199 | set_tracer_flags(1 << index, val); |
a8259075 SR |
4200 | |
4201 | *ppos += cnt; | |
4202 | ||
4203 | return cnt; | |
4204 | } | |
4205 | ||
a8259075 SR |
4206 | static const struct file_operations trace_options_core_fops = { |
4207 | .open = tracing_open_generic, | |
4208 | .read = trace_options_core_read, | |
4209 | .write = trace_options_core_write, | |
b444786f | 4210 | .llseek = generic_file_llseek, |
a8259075 SR |
4211 | }; |
4212 | ||
5452af66 FW |
4213 | struct dentry *trace_create_file(const char *name, |
4214 | mode_t mode, | |
4215 | struct dentry *parent, | |
4216 | void *data, | |
4217 | const struct file_operations *fops) | |
4218 | { | |
4219 | struct dentry *ret; | |
4220 | ||
4221 | ret = debugfs_create_file(name, mode, parent, data, fops); | |
4222 | if (!ret) | |
4223 | pr_warning("Could not create debugfs '%s' entry\n", name); | |
4224 | ||
4225 | return ret; | |
4226 | } | |
4227 | ||
4228 | ||
a8259075 SR |
4229 | static struct dentry *trace_options_init_dentry(void) |
4230 | { | |
4231 | struct dentry *d_tracer; | |
4232 | static struct dentry *t_options; | |
4233 | ||
4234 | if (t_options) | |
4235 | return t_options; | |
4236 | ||
4237 | d_tracer = tracing_init_dentry(); | |
4238 | if (!d_tracer) | |
4239 | return NULL; | |
4240 | ||
4241 | t_options = debugfs_create_dir("options", d_tracer); | |
4242 | if (!t_options) { | |
4243 | pr_warning("Could not create debugfs directory 'options'\n"); | |
4244 | return NULL; | |
4245 | } | |
4246 | ||
4247 | return t_options; | |
4248 | } | |
4249 | ||
577b785f SR |
4250 | static void |
4251 | create_trace_option_file(struct trace_option_dentry *topt, | |
4252 | struct tracer_flags *flags, | |
4253 | struct tracer_opt *opt) | |
4254 | { | |
4255 | struct dentry *t_options; | |
577b785f SR |
4256 | |
4257 | t_options = trace_options_init_dentry(); | |
4258 | if (!t_options) | |
4259 | return; | |
4260 | ||
4261 | topt->flags = flags; | |
4262 | topt->opt = opt; | |
4263 | ||
5452af66 | 4264 | topt->entry = trace_create_file(opt->name, 0644, t_options, topt, |
577b785f SR |
4265 | &trace_options_fops); |
4266 | ||
577b785f SR |
4267 | } |
4268 | ||
4269 | static struct trace_option_dentry * | |
4270 | create_trace_option_files(struct tracer *tracer) | |
4271 | { | |
4272 | struct trace_option_dentry *topts; | |
4273 | struct tracer_flags *flags; | |
4274 | struct tracer_opt *opts; | |
4275 | int cnt; | |
4276 | ||
4277 | if (!tracer) | |
4278 | return NULL; | |
4279 | ||
4280 | flags = tracer->flags; | |
4281 | ||
4282 | if (!flags || !flags->opts) | |
4283 | return NULL; | |
4284 | ||
4285 | opts = flags->opts; | |
4286 | ||
4287 | for (cnt = 0; opts[cnt].name; cnt++) | |
4288 | ; | |
4289 | ||
0cfe8245 | 4290 | topts = kcalloc(cnt + 1, sizeof(*topts), GFP_KERNEL); |
577b785f SR |
4291 | if (!topts) |
4292 | return NULL; | |
4293 | ||
4294 | for (cnt = 0; opts[cnt].name; cnt++) | |
4295 | create_trace_option_file(&topts[cnt], flags, | |
4296 | &opts[cnt]); | |
4297 | ||
4298 | return topts; | |
4299 | } | |
4300 | ||
4301 | static void | |
4302 | destroy_trace_option_files(struct trace_option_dentry *topts) | |
4303 | { | |
4304 | int cnt; | |
4305 | ||
4306 | if (!topts) | |
4307 | return; | |
4308 | ||
4309 | for (cnt = 0; topts[cnt].opt; cnt++) { | |
4310 | if (topts[cnt].entry) | |
4311 | debugfs_remove(topts[cnt].entry); | |
4312 | } | |
4313 | ||
4314 | kfree(topts); | |
4315 | } | |
4316 | ||
a8259075 SR |
4317 | static struct dentry * |
4318 | create_trace_option_core_file(const char *option, long index) | |
4319 | { | |
4320 | struct dentry *t_options; | |
a8259075 SR |
4321 | |
4322 | t_options = trace_options_init_dentry(); | |
4323 | if (!t_options) | |
4324 | return NULL; | |
4325 | ||
5452af66 | 4326 | return trace_create_file(option, 0644, t_options, (void *)index, |
a8259075 | 4327 | &trace_options_core_fops); |
a8259075 SR |
4328 | } |
4329 | ||
4330 | static __init void create_trace_options_dir(void) | |
4331 | { | |
4332 | struct dentry *t_options; | |
a8259075 SR |
4333 | int i; |
4334 | ||
4335 | t_options = trace_options_init_dentry(); | |
4336 | if (!t_options) | |
4337 | return; | |
4338 | ||
5452af66 FW |
4339 | for (i = 0; trace_options[i]; i++) |
4340 | create_trace_option_core_file(trace_options[i], i); | |
a8259075 SR |
4341 | } |
4342 | ||
b5ad384e | 4343 | static __init int tracer_init_debugfs(void) |
bc0c38d1 SR |
4344 | { |
4345 | struct dentry *d_tracer; | |
b04cc6b1 | 4346 | int cpu; |
bc0c38d1 | 4347 | |
7e53bd42 LJ |
4348 | trace_access_lock_init(); |
4349 | ||
bc0c38d1 SR |
4350 | d_tracer = tracing_init_dentry(); |
4351 | ||
5452af66 FW |
4352 | trace_create_file("tracing_enabled", 0644, d_tracer, |
4353 | &global_trace, &tracing_ctrl_fops); | |
bc0c38d1 | 4354 | |
5452af66 FW |
4355 | trace_create_file("trace_options", 0644, d_tracer, |
4356 | NULL, &tracing_iter_fops); | |
bc0c38d1 | 4357 | |
5452af66 FW |
4358 | trace_create_file("tracing_cpumask", 0644, d_tracer, |
4359 | NULL, &tracing_cpumask_fops); | |
4360 | ||
4361 | trace_create_file("trace", 0644, d_tracer, | |
4362 | (void *) TRACE_PIPE_ALL_CPU, &tracing_fops); | |
a8259075 | 4363 | |
5452af66 FW |
4364 | trace_create_file("available_tracers", 0444, d_tracer, |
4365 | &global_trace, &show_traces_fops); | |
4366 | ||
339ae5d3 | 4367 | trace_create_file("current_tracer", 0644, d_tracer, |
5452af66 FW |
4368 | &global_trace, &set_tracer_fops); |
4369 | ||
5d4a9dba | 4370 | #ifdef CONFIG_TRACER_MAX_TRACE |
5452af66 FW |
4371 | trace_create_file("tracing_max_latency", 0644, d_tracer, |
4372 | &tracing_max_latency, &tracing_max_lat_fops); | |
0e950173 | 4373 | #endif |
5452af66 FW |
4374 | |
4375 | trace_create_file("tracing_thresh", 0644, d_tracer, | |
4376 | &tracing_thresh, &tracing_max_lat_fops); | |
a8259075 | 4377 | |
339ae5d3 | 4378 | trace_create_file("README", 0444, d_tracer, |
5452af66 FW |
4379 | NULL, &tracing_readme_fops); |
4380 | ||
4381 | trace_create_file("trace_pipe", 0444, d_tracer, | |
b04cc6b1 | 4382 | (void *) TRACE_PIPE_ALL_CPU, &tracing_pipe_fops); |
5452af66 FW |
4383 | |
4384 | trace_create_file("buffer_size_kb", 0644, d_tracer, | |
4385 | &global_trace, &tracing_entries_fops); | |
4386 | ||
4f271a2a VN |
4387 | trace_create_file("free_buffer", 0644, d_tracer, |
4388 | &global_trace, &tracing_free_buffer_fops); | |
4389 | ||
5452af66 FW |
4390 | trace_create_file("trace_marker", 0220, d_tracer, |
4391 | NULL, &tracing_mark_fops); | |
5bf9a1ee | 4392 | |
69abe6a5 AP |
4393 | trace_create_file("saved_cmdlines", 0444, d_tracer, |
4394 | NULL, &tracing_saved_cmdlines_fops); | |
5bf9a1ee | 4395 | |
5079f326 Z |
4396 | trace_create_file("trace_clock", 0644, d_tracer, NULL, |
4397 | &trace_clock_fops); | |
4398 | ||
bc0c38d1 | 4399 | #ifdef CONFIG_DYNAMIC_FTRACE |
5452af66 FW |
4400 | trace_create_file("dyn_ftrace_total_info", 0444, d_tracer, |
4401 | &ftrace_update_tot_cnt, &tracing_dyn_info_fops); | |
bc0c38d1 | 4402 | #endif |
b04cc6b1 | 4403 | |
5452af66 FW |
4404 | create_trace_options_dir(); |
4405 | ||
b04cc6b1 FW |
4406 | for_each_tracing_cpu(cpu) |
4407 | tracing_init_debugfs_percpu(cpu); | |
4408 | ||
b5ad384e | 4409 | return 0; |
bc0c38d1 SR |
4410 | } |
4411 | ||
3f5a54e3 SR |
4412 | static int trace_panic_handler(struct notifier_block *this, |
4413 | unsigned long event, void *unused) | |
4414 | { | |
944ac425 | 4415 | if (ftrace_dump_on_oops) |
cecbca96 | 4416 | ftrace_dump(ftrace_dump_on_oops); |
3f5a54e3 SR |
4417 | return NOTIFY_OK; |
4418 | } | |
4419 | ||
4420 | static struct notifier_block trace_panic_notifier = { | |
4421 | .notifier_call = trace_panic_handler, | |
4422 | .next = NULL, | |
4423 | .priority = 150 /* priority: INT_MAX >= x >= 0 */ | |
4424 | }; | |
4425 | ||
4426 | static int trace_die_handler(struct notifier_block *self, | |
4427 | unsigned long val, | |
4428 | void *data) | |
4429 | { | |
4430 | switch (val) { | |
4431 | case DIE_OOPS: | |
944ac425 | 4432 | if (ftrace_dump_on_oops) |
cecbca96 | 4433 | ftrace_dump(ftrace_dump_on_oops); |
3f5a54e3 SR |
4434 | break; |
4435 | default: | |
4436 | break; | |
4437 | } | |
4438 | return NOTIFY_OK; | |
4439 | } | |
4440 | ||
4441 | static struct notifier_block trace_die_notifier = { | |
4442 | .notifier_call = trace_die_handler, | |
4443 | .priority = 200 | |
4444 | }; | |
4445 | ||
4446 | /* | |
4447 | * printk is set to max of 1024, we really don't need it that big. | |
4448 | * Nothing should be printing 1000 characters anyway. | |
4449 | */ | |
4450 | #define TRACE_MAX_PRINT 1000 | |
4451 | ||
4452 | /* | |
4453 | * Define here KERN_TRACE so that we have one place to modify | |
4454 | * it if we decide to change what log level the ftrace dump | |
4455 | * should be at. | |
4456 | */ | |
428aee14 | 4457 | #define KERN_TRACE KERN_EMERG |
3f5a54e3 | 4458 | |
955b61e5 | 4459 | void |
3f5a54e3 SR |
4460 | trace_printk_seq(struct trace_seq *s) |
4461 | { | |
4462 | /* Probably should print a warning here. */ | |
4463 | if (s->len >= 1000) | |
4464 | s->len = 1000; | |
4465 | ||
4466 | /* should be zero ended, but we are paranoid. */ | |
4467 | s->buffer[s->len] = 0; | |
4468 | ||
4469 | printk(KERN_TRACE "%s", s->buffer); | |
4470 | ||
f9520750 | 4471 | trace_seq_init(s); |
3f5a54e3 SR |
4472 | } |
4473 | ||
955b61e5 JW |
4474 | void trace_init_global_iter(struct trace_iterator *iter) |
4475 | { | |
4476 | iter->tr = &global_trace; | |
4477 | iter->trace = current_trace; | |
4478 | iter->cpu_file = TRACE_PIPE_ALL_CPU; | |
4479 | } | |
4480 | ||
cecbca96 FW |
4481 | static void |
4482 | __ftrace_dump(bool disable_tracing, enum ftrace_dump_mode oops_dump_mode) | |
3f5a54e3 | 4483 | { |
445c8951 | 4484 | static arch_spinlock_t ftrace_dump_lock = |
edc35bd7 | 4485 | (arch_spinlock_t)__ARCH_SPIN_LOCK_UNLOCKED; |
3f5a54e3 SR |
4486 | /* use static because iter can be a bit big for the stack */ |
4487 | static struct trace_iterator iter; | |
cf586b61 | 4488 | unsigned int old_userobj; |
3f5a54e3 | 4489 | static int dump_ran; |
d769041f SR |
4490 | unsigned long flags; |
4491 | int cnt = 0, cpu; | |
3f5a54e3 SR |
4492 | |
4493 | /* only one dump */ | |
cd891ae0 | 4494 | local_irq_save(flags); |
0199c4e6 | 4495 | arch_spin_lock(&ftrace_dump_lock); |
3f5a54e3 SR |
4496 | if (dump_ran) |
4497 | goto out; | |
4498 | ||
4499 | dump_ran = 1; | |
4500 | ||
0ee6b6cf | 4501 | tracing_off(); |
cf586b61 FW |
4502 | |
4503 | if (disable_tracing) | |
4504 | ftrace_kill(); | |
3f5a54e3 | 4505 | |
955b61e5 JW |
4506 | trace_init_global_iter(&iter); |
4507 | ||
d769041f | 4508 | for_each_tracing_cpu(cpu) { |
955b61e5 | 4509 | atomic_inc(&iter.tr->data[cpu]->disabled); |
d769041f SR |
4510 | } |
4511 | ||
cf586b61 FW |
4512 | old_userobj = trace_flags & TRACE_ITER_SYM_USEROBJ; |
4513 | ||
b54d3de9 TE |
4514 | /* don't look at user memory in panic mode */ |
4515 | trace_flags &= ~TRACE_ITER_SYM_USEROBJ; | |
4516 | ||
e543ad76 | 4517 | /* Simulate the iterator */ |
3f5a54e3 SR |
4518 | iter.tr = &global_trace; |
4519 | iter.trace = current_trace; | |
cecbca96 FW |
4520 | |
4521 | switch (oops_dump_mode) { | |
4522 | case DUMP_ALL: | |
4523 | iter.cpu_file = TRACE_PIPE_ALL_CPU; | |
4524 | break; | |
4525 | case DUMP_ORIG: | |
4526 | iter.cpu_file = raw_smp_processor_id(); | |
4527 | break; | |
4528 | case DUMP_NONE: | |
4529 | goto out_enable; | |
4530 | default: | |
4531 | printk(KERN_TRACE "Bad dumping mode, switching to all CPUs dump\n"); | |
4532 | iter.cpu_file = TRACE_PIPE_ALL_CPU; | |
4533 | } | |
4534 | ||
4535 | printk(KERN_TRACE "Dumping ftrace buffer:\n"); | |
3f5a54e3 SR |
4536 | |
4537 | /* | |
4538 | * We need to stop all tracing on all CPUS to read the | |
4539 | * the next buffer. This is a bit expensive, but is | |
4540 | * not done often. We fill all what we can read, | |
4541 | * and then release the locks again. | |
4542 | */ | |
4543 | ||
3f5a54e3 SR |
4544 | while (!trace_empty(&iter)) { |
4545 | ||
4546 | if (!cnt) | |
4547 | printk(KERN_TRACE "---------------------------------\n"); | |
4548 | ||
4549 | cnt++; | |
4550 | ||
4551 | /* reset all but tr, trace, and overruns */ | |
4552 | memset(&iter.seq, 0, | |
4553 | sizeof(struct trace_iterator) - | |
4554 | offsetof(struct trace_iterator, seq)); | |
4555 | iter.iter_flags |= TRACE_FILE_LAT_FMT; | |
4556 | iter.pos = -1; | |
4557 | ||
955b61e5 | 4558 | if (trace_find_next_entry_inc(&iter) != NULL) { |
74e7ff8c LJ |
4559 | int ret; |
4560 | ||
4561 | ret = print_trace_line(&iter); | |
4562 | if (ret != TRACE_TYPE_NO_CONSUME) | |
4563 | trace_consume(&iter); | |
3f5a54e3 SR |
4564 | } |
4565 | ||
4566 | trace_printk_seq(&iter.seq); | |
4567 | } | |
4568 | ||
4569 | if (!cnt) | |
4570 | printk(KERN_TRACE " (ftrace buffer empty)\n"); | |
4571 | else | |
4572 | printk(KERN_TRACE "---------------------------------\n"); | |
4573 | ||
cecbca96 | 4574 | out_enable: |
cf586b61 FW |
4575 | /* Re-enable tracing if requested */ |
4576 | if (!disable_tracing) { | |
4577 | trace_flags |= old_userobj; | |
4578 | ||
4579 | for_each_tracing_cpu(cpu) { | |
955b61e5 | 4580 | atomic_dec(&iter.tr->data[cpu]->disabled); |
cf586b61 FW |
4581 | } |
4582 | tracing_on(); | |
4583 | } | |
4584 | ||
3f5a54e3 | 4585 | out: |
0199c4e6 | 4586 | arch_spin_unlock(&ftrace_dump_lock); |
cd891ae0 | 4587 | local_irq_restore(flags); |
3f5a54e3 SR |
4588 | } |
4589 | ||
cf586b61 | 4590 | /* By default: disable tracing after the dump */ |
cecbca96 | 4591 | void ftrace_dump(enum ftrace_dump_mode oops_dump_mode) |
cf586b61 | 4592 | { |
cecbca96 | 4593 | __ftrace_dump(true, oops_dump_mode); |
cf586b61 FW |
4594 | } |
4595 | ||
3928a8a2 | 4596 | __init static int tracer_alloc_buffers(void) |
bc0c38d1 | 4597 | { |
73c5162a | 4598 | int ring_buf_size; |
750912fa | 4599 | enum ring_buffer_flags rb_flags; |
4c11d7ae | 4600 | int i; |
9e01c1b7 | 4601 | int ret = -ENOMEM; |
4c11d7ae | 4602 | |
750912fa | 4603 | |
9e01c1b7 RR |
4604 | if (!alloc_cpumask_var(&tracing_buffer_mask, GFP_KERNEL)) |
4605 | goto out; | |
4606 | ||
4607 | if (!alloc_cpumask_var(&tracing_cpumask, GFP_KERNEL)) | |
4608 | goto out_free_buffer_mask; | |
4c11d7ae | 4609 | |
73c5162a SR |
4610 | /* To save memory, keep the ring buffer size to its minimum */ |
4611 | if (ring_buffer_expanded) | |
4612 | ring_buf_size = trace_buf_size; | |
4613 | else | |
4614 | ring_buf_size = 1; | |
4615 | ||
750912fa DS |
4616 | rb_flags = trace_flags & TRACE_ITER_OVERWRITE ? RB_FL_OVERWRITE : 0; |
4617 | ||
9e01c1b7 RR |
4618 | cpumask_copy(tracing_buffer_mask, cpu_possible_mask); |
4619 | cpumask_copy(tracing_cpumask, cpu_all_mask); | |
4620 | ||
4621 | /* TODO: make the number of buffers hot pluggable with CPUS */ | |
750912fa | 4622 | global_trace.buffer = ring_buffer_alloc(ring_buf_size, rb_flags); |
3928a8a2 SR |
4623 | if (!global_trace.buffer) { |
4624 | printk(KERN_ERR "tracer: failed to allocate ring buffer!\n"); | |
4625 | WARN_ON(1); | |
9e01c1b7 | 4626 | goto out_free_cpumask; |
4c11d7ae | 4627 | } |
3928a8a2 | 4628 | global_trace.entries = ring_buffer_size(global_trace.buffer); |
4c11d7ae | 4629 | |
9e01c1b7 | 4630 | |
4c11d7ae | 4631 | #ifdef CONFIG_TRACER_MAX_TRACE |
750912fa | 4632 | max_tr.buffer = ring_buffer_alloc(1, rb_flags); |
3928a8a2 SR |
4633 | if (!max_tr.buffer) { |
4634 | printk(KERN_ERR "tracer: failed to allocate max ring buffer!\n"); | |
4635 | WARN_ON(1); | |
4636 | ring_buffer_free(global_trace.buffer); | |
9e01c1b7 | 4637 | goto out_free_cpumask; |
4c11d7ae | 4638 | } |
ef710e10 | 4639 | max_tr.entries = 1; |
a98a3c3f | 4640 | #endif |
ab46428c | 4641 | |
4c11d7ae | 4642 | /* Allocate the first page for all buffers */ |
ab46428c | 4643 | for_each_tracing_cpu(i) { |
566b0aaf | 4644 | global_trace.data[i] = &per_cpu(global_trace_cpu, i); |
9705f69e | 4645 | max_tr.data[i] = &per_cpu(max_tr_data, i); |
4c11d7ae | 4646 | } |
bc0c38d1 | 4647 | |
bc0c38d1 SR |
4648 | trace_init_cmdlines(); |
4649 | ||
43a15386 | 4650 | register_tracer(&nop_trace); |
79fb0768 | 4651 | current_trace = &nop_trace; |
60a11774 SR |
4652 | /* All seems OK, enable tracing */ |
4653 | tracing_disabled = 0; | |
3928a8a2 | 4654 | |
3f5a54e3 SR |
4655 | atomic_notifier_chain_register(&panic_notifier_list, |
4656 | &trace_panic_notifier); | |
4657 | ||
4658 | register_die_notifier(&trace_die_notifier); | |
2fc1dfbe FW |
4659 | |
4660 | return 0; | |
3f5a54e3 | 4661 | |
9e01c1b7 RR |
4662 | out_free_cpumask: |
4663 | free_cpumask_var(tracing_cpumask); | |
4664 | out_free_buffer_mask: | |
4665 | free_cpumask_var(tracing_buffer_mask); | |
4666 | out: | |
4667 | return ret; | |
bc0c38d1 | 4668 | } |
b2821ae6 SR |
4669 | |
4670 | __init static int clear_boot_tracer(void) | |
4671 | { | |
4672 | /* | |
4673 | * The default tracer at boot buffer is an init section. | |
4674 | * This function is called in lateinit. If we did not | |
4675 | * find the boot tracer, then clear it out, to prevent | |
4676 | * later registration from accessing the buffer that is | |
4677 | * about to be freed. | |
4678 | */ | |
4679 | if (!default_bootup_tracer) | |
4680 | return 0; | |
4681 | ||
4682 | printk(KERN_INFO "ftrace bootup tracer '%s' not registered.\n", | |
4683 | default_bootup_tracer); | |
4684 | default_bootup_tracer = NULL; | |
4685 | ||
4686 | return 0; | |
4687 | } | |
4688 | ||
b5ad384e FW |
4689 | early_initcall(tracer_alloc_buffers); |
4690 | fs_initcall(tracer_init_debugfs); | |
b2821ae6 | 4691 | late_initcall(clear_boot_tracer); |