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Commit | Line | Data |
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bc0c38d1 SR |
1 | /* |
2 | * ring buffer based function tracer | |
3 | * | |
4 | * Copyright (C) 2007-2008 Steven Rostedt <srostedt@redhat.com> | |
5 | * Copyright (C) 2008 Ingo Molnar <mingo@redhat.com> | |
6 | * | |
7 | * Originally taken from the RT patch by: | |
8 | * Arnaldo Carvalho de Melo <acme@redhat.com> | |
9 | * | |
10 | * Based on code from the latency_tracer, that is: | |
11 | * Copyright (C) 2004-2006 Ingo Molnar | |
12 | * Copyright (C) 2004 William Lee Irwin III | |
13 | */ | |
2cadf913 | 14 | #include <linux/ring_buffer.h> |
273b281f | 15 | #include <generated/utsrelease.h> |
2cadf913 SR |
16 | #include <linux/stacktrace.h> |
17 | #include <linux/writeback.h> | |
bc0c38d1 SR |
18 | #include <linux/kallsyms.h> |
19 | #include <linux/seq_file.h> | |
3f5a54e3 | 20 | #include <linux/notifier.h> |
2cadf913 | 21 | #include <linux/irqflags.h> |
bc0c38d1 | 22 | #include <linux/debugfs.h> |
4c11d7ae | 23 | #include <linux/pagemap.h> |
bc0c38d1 SR |
24 | #include <linux/hardirq.h> |
25 | #include <linux/linkage.h> | |
26 | #include <linux/uaccess.h> | |
2cadf913 | 27 | #include <linux/kprobes.h> |
bc0c38d1 SR |
28 | #include <linux/ftrace.h> |
29 | #include <linux/module.h> | |
30 | #include <linux/percpu.h> | |
2cadf913 | 31 | #include <linux/splice.h> |
3f5a54e3 | 32 | #include <linux/kdebug.h> |
5f0c6c03 | 33 | #include <linux/string.h> |
7e53bd42 | 34 | #include <linux/rwsem.h> |
5a0e3ad6 | 35 | #include <linux/slab.h> |
bc0c38d1 SR |
36 | #include <linux/ctype.h> |
37 | #include <linux/init.h> | |
2a2cc8f7 | 38 | #include <linux/poll.h> |
b892e5c8 | 39 | #include <linux/nmi.h> |
bc0c38d1 | 40 | #include <linux/fs.h> |
86387f7e | 41 | |
bc0c38d1 | 42 | #include "trace.h" |
f0868d1e | 43 | #include "trace_output.h" |
bc0c38d1 | 44 | |
73c5162a SR |
45 | /* |
46 | * On boot up, the ring buffer is set to the minimum size, so that | |
47 | * we do not waste memory on systems that are not using tracing. | |
48 | */ | |
020e5f85 | 49 | int ring_buffer_expanded; |
73c5162a | 50 | |
8e1b82e0 FW |
51 | /* |
52 | * We need to change this state when a selftest is running. | |
ff32504f FW |
53 | * A selftest will lurk into the ring-buffer to count the |
54 | * entries inserted during the selftest although some concurrent | |
5e1607a0 | 55 | * insertions into the ring-buffer such as trace_printk could occurred |
ff32504f FW |
56 | * at the same time, giving false positive or negative results. |
57 | */ | |
8e1b82e0 | 58 | static bool __read_mostly tracing_selftest_running; |
ff32504f | 59 | |
b2821ae6 SR |
60 | /* |
61 | * If a tracer is running, we do not want to run SELFTEST. | |
62 | */ | |
020e5f85 | 63 | bool __read_mostly tracing_selftest_disabled; |
b2821ae6 | 64 | |
adf9f195 FW |
65 | /* For tracers that don't implement custom flags */ |
66 | static struct tracer_opt dummy_tracer_opt[] = { | |
67 | { } | |
68 | }; | |
69 | ||
70 | static struct tracer_flags dummy_tracer_flags = { | |
71 | .val = 0, | |
72 | .opts = dummy_tracer_opt | |
73 | }; | |
74 | ||
75 | static int dummy_set_flag(u32 old_flags, u32 bit, int set) | |
76 | { | |
77 | return 0; | |
78 | } | |
0f048701 SR |
79 | |
80 | /* | |
81 | * Kill all tracing for good (never come back). | |
82 | * It is initialized to 1 but will turn to zero if the initialization | |
83 | * of the tracer is successful. But that is the only place that sets | |
84 | * this back to zero. | |
85 | */ | |
4fd27358 | 86 | static int tracing_disabled = 1; |
0f048701 | 87 | |
9288f99a | 88 | DEFINE_PER_CPU(int, ftrace_cpu_disabled); |
d769041f | 89 | |
955b61e5 | 90 | cpumask_var_t __read_mostly tracing_buffer_mask; |
ab46428c | 91 | |
944ac425 SR |
92 | /* |
93 | * ftrace_dump_on_oops - variable to dump ftrace buffer on oops | |
94 | * | |
95 | * If there is an oops (or kernel panic) and the ftrace_dump_on_oops | |
96 | * is set, then ftrace_dump is called. This will output the contents | |
97 | * of the ftrace buffers to the console. This is very useful for | |
98 | * capturing traces that lead to crashes and outputing it to a | |
99 | * serial console. | |
100 | * | |
101 | * It is default off, but you can enable it with either specifying | |
102 | * "ftrace_dump_on_oops" in the kernel command line, or setting | |
cecbca96 FW |
103 | * /proc/sys/kernel/ftrace_dump_on_oops |
104 | * Set 1 if you want to dump buffers of all CPUs | |
105 | * Set 2 if you want to dump the buffer of the CPU that triggered oops | |
944ac425 | 106 | */ |
cecbca96 FW |
107 | |
108 | enum ftrace_dump_mode ftrace_dump_on_oops; | |
944ac425 | 109 | |
b2821ae6 SR |
110 | static int tracing_set_tracer(const char *buf); |
111 | ||
ee6c2c1b LZ |
112 | #define MAX_TRACER_SIZE 100 |
113 | static char bootup_tracer_buf[MAX_TRACER_SIZE] __initdata; | |
b2821ae6 | 114 | static char *default_bootup_tracer; |
d9e54076 | 115 | |
1beee96b | 116 | static int __init set_cmdline_ftrace(char *str) |
d9e54076 | 117 | { |
ee6c2c1b | 118 | strncpy(bootup_tracer_buf, str, MAX_TRACER_SIZE); |
b2821ae6 | 119 | default_bootup_tracer = bootup_tracer_buf; |
73c5162a SR |
120 | /* We are using ftrace early, expand it */ |
121 | ring_buffer_expanded = 1; | |
d9e54076 PZ |
122 | return 1; |
123 | } | |
1beee96b | 124 | __setup("ftrace=", set_cmdline_ftrace); |
d9e54076 | 125 | |
944ac425 SR |
126 | static int __init set_ftrace_dump_on_oops(char *str) |
127 | { | |
cecbca96 FW |
128 | if (*str++ != '=' || !*str) { |
129 | ftrace_dump_on_oops = DUMP_ALL; | |
130 | return 1; | |
131 | } | |
132 | ||
133 | if (!strcmp("orig_cpu", str)) { | |
134 | ftrace_dump_on_oops = DUMP_ORIG; | |
135 | return 1; | |
136 | } | |
137 | ||
138 | return 0; | |
944ac425 SR |
139 | } |
140 | __setup("ftrace_dump_on_oops", set_ftrace_dump_on_oops); | |
60a11774 | 141 | |
cf8e3474 | 142 | unsigned long long ns2usecs(cycle_t nsec) |
bc0c38d1 SR |
143 | { |
144 | nsec += 500; | |
145 | do_div(nsec, 1000); | |
146 | return nsec; | |
147 | } | |
148 | ||
4fcdae83 SR |
149 | /* |
150 | * The global_trace is the descriptor that holds the tracing | |
151 | * buffers for the live tracing. For each CPU, it contains | |
152 | * a link list of pages that will store trace entries. The | |
153 | * page descriptor of the pages in the memory is used to hold | |
154 | * the link list by linking the lru item in the page descriptor | |
155 | * to each of the pages in the buffer per CPU. | |
156 | * | |
157 | * For each active CPU there is a data field that holds the | |
158 | * pages for the buffer for that CPU. Each CPU has the same number | |
159 | * of pages allocated for its buffer. | |
160 | */ | |
bc0c38d1 SR |
161 | static struct trace_array global_trace; |
162 | ||
163 | static DEFINE_PER_CPU(struct trace_array_cpu, global_trace_cpu); | |
164 | ||
e77405ad SR |
165 | int filter_current_check_discard(struct ring_buffer *buffer, |
166 | struct ftrace_event_call *call, void *rec, | |
eb02ce01 TZ |
167 | struct ring_buffer_event *event) |
168 | { | |
e77405ad | 169 | return filter_check_discard(call, rec, buffer, event); |
eb02ce01 | 170 | } |
17c873ec | 171 | EXPORT_SYMBOL_GPL(filter_current_check_discard); |
eb02ce01 | 172 | |
37886f6a SR |
173 | cycle_t ftrace_now(int cpu) |
174 | { | |
175 | u64 ts; | |
176 | ||
177 | /* Early boot up does not have a buffer yet */ | |
178 | if (!global_trace.buffer) | |
179 | return trace_clock_local(); | |
180 | ||
181 | ts = ring_buffer_time_stamp(global_trace.buffer, cpu); | |
182 | ring_buffer_normalize_time_stamp(global_trace.buffer, cpu, &ts); | |
183 | ||
184 | return ts; | |
185 | } | |
bc0c38d1 | 186 | |
4fcdae83 SR |
187 | /* |
188 | * The max_tr is used to snapshot the global_trace when a maximum | |
189 | * latency is reached. Some tracers will use this to store a maximum | |
190 | * trace while it continues examining live traces. | |
191 | * | |
192 | * The buffers for the max_tr are set up the same as the global_trace. | |
193 | * When a snapshot is taken, the link list of the max_tr is swapped | |
194 | * with the link list of the global_trace and the buffers are reset for | |
195 | * the global_trace so the tracing can continue. | |
196 | */ | |
bc0c38d1 SR |
197 | static struct trace_array max_tr; |
198 | ||
9705f69e | 199 | static DEFINE_PER_CPU(struct trace_array_cpu, max_tr_data); |
bc0c38d1 | 200 | |
4fcdae83 | 201 | /* tracer_enabled is used to toggle activation of a tracer */ |
26994ead | 202 | static int tracer_enabled = 1; |
4fcdae83 | 203 | |
9036990d SR |
204 | /** |
205 | * tracing_is_enabled - return tracer_enabled status | |
206 | * | |
207 | * This function is used by other tracers to know the status | |
208 | * of the tracer_enabled flag. Tracers may use this function | |
209 | * to know if it should enable their features when starting | |
210 | * up. See irqsoff tracer for an example (start_irqsoff_tracer). | |
211 | */ | |
212 | int tracing_is_enabled(void) | |
213 | { | |
214 | return tracer_enabled; | |
215 | } | |
216 | ||
4fcdae83 | 217 | /* |
3928a8a2 SR |
218 | * trace_buf_size is the size in bytes that is allocated |
219 | * for a buffer. Note, the number of bytes is always rounded | |
220 | * to page size. | |
3f5a54e3 SR |
221 | * |
222 | * This number is purposely set to a low number of 16384. | |
223 | * If the dump on oops happens, it will be much appreciated | |
224 | * to not have to wait for all that output. Anyway this can be | |
225 | * boot time and run time configurable. | |
4fcdae83 | 226 | */ |
3928a8a2 | 227 | #define TRACE_BUF_SIZE_DEFAULT 1441792UL /* 16384 * 88 (sizeof(entry)) */ |
3f5a54e3 | 228 | |
3928a8a2 | 229 | static unsigned long trace_buf_size = TRACE_BUF_SIZE_DEFAULT; |
bc0c38d1 | 230 | |
4fcdae83 | 231 | /* trace_types holds a link list of available tracers. */ |
bc0c38d1 | 232 | static struct tracer *trace_types __read_mostly; |
4fcdae83 SR |
233 | |
234 | /* current_trace points to the tracer that is currently active */ | |
bc0c38d1 | 235 | static struct tracer *current_trace __read_mostly; |
4fcdae83 | 236 | |
4fcdae83 SR |
237 | /* |
238 | * trace_types_lock is used to protect the trace_types list. | |
4fcdae83 | 239 | */ |
bc0c38d1 | 240 | static DEFINE_MUTEX(trace_types_lock); |
4fcdae83 | 241 | |
7e53bd42 LJ |
242 | /* |
243 | * serialize the access of the ring buffer | |
244 | * | |
245 | * ring buffer serializes readers, but it is low level protection. | |
246 | * The validity of the events (which returns by ring_buffer_peek() ..etc) | |
247 | * are not protected by ring buffer. | |
248 | * | |
249 | * The content of events may become garbage if we allow other process consumes | |
250 | * these events concurrently: | |
251 | * A) the page of the consumed events may become a normal page | |
252 | * (not reader page) in ring buffer, and this page will be rewrited | |
253 | * by events producer. | |
254 | * B) The page of the consumed events may become a page for splice_read, | |
255 | * and this page will be returned to system. | |
256 | * | |
257 | * These primitives allow multi process access to different cpu ring buffer | |
258 | * concurrently. | |
259 | * | |
260 | * These primitives don't distinguish read-only and read-consume access. | |
261 | * Multi read-only access are also serialized. | |
262 | */ | |
263 | ||
264 | #ifdef CONFIG_SMP | |
265 | static DECLARE_RWSEM(all_cpu_access_lock); | |
266 | static DEFINE_PER_CPU(struct mutex, cpu_access_lock); | |
267 | ||
268 | static inline void trace_access_lock(int cpu) | |
269 | { | |
270 | if (cpu == TRACE_PIPE_ALL_CPU) { | |
271 | /* gain it for accessing the whole ring buffer. */ | |
272 | down_write(&all_cpu_access_lock); | |
273 | } else { | |
274 | /* gain it for accessing a cpu ring buffer. */ | |
275 | ||
276 | /* Firstly block other trace_access_lock(TRACE_PIPE_ALL_CPU). */ | |
277 | down_read(&all_cpu_access_lock); | |
278 | ||
279 | /* Secondly block other access to this @cpu ring buffer. */ | |
280 | mutex_lock(&per_cpu(cpu_access_lock, cpu)); | |
281 | } | |
282 | } | |
283 | ||
284 | static inline void trace_access_unlock(int cpu) | |
285 | { | |
286 | if (cpu == TRACE_PIPE_ALL_CPU) { | |
287 | up_write(&all_cpu_access_lock); | |
288 | } else { | |
289 | mutex_unlock(&per_cpu(cpu_access_lock, cpu)); | |
290 | up_read(&all_cpu_access_lock); | |
291 | } | |
292 | } | |
293 | ||
294 | static inline void trace_access_lock_init(void) | |
295 | { | |
296 | int cpu; | |
297 | ||
298 | for_each_possible_cpu(cpu) | |
299 | mutex_init(&per_cpu(cpu_access_lock, cpu)); | |
300 | } | |
301 | ||
302 | #else | |
303 | ||
304 | static DEFINE_MUTEX(access_lock); | |
305 | ||
306 | static inline void trace_access_lock(int cpu) | |
307 | { | |
308 | (void)cpu; | |
309 | mutex_lock(&access_lock); | |
310 | } | |
311 | ||
312 | static inline void trace_access_unlock(int cpu) | |
313 | { | |
314 | (void)cpu; | |
315 | mutex_unlock(&access_lock); | |
316 | } | |
317 | ||
318 | static inline void trace_access_lock_init(void) | |
319 | { | |
320 | } | |
321 | ||
322 | #endif | |
323 | ||
4fcdae83 | 324 | /* trace_wait is a waitqueue for tasks blocked on trace_poll */ |
4e655519 IM |
325 | static DECLARE_WAIT_QUEUE_HEAD(trace_wait); |
326 | ||
ee6bce52 | 327 | /* trace_flags holds trace_options default values */ |
12ef7d44 | 328 | unsigned long trace_flags = TRACE_ITER_PRINT_PARENT | TRACE_ITER_PRINTK | |
a2a16d6a | 329 | TRACE_ITER_ANNOTATE | TRACE_ITER_CONTEXT_INFO | TRACE_ITER_SLEEP_TIME | |
77271ce4 SR |
330 | TRACE_ITER_GRAPH_TIME | TRACE_ITER_RECORD_CMD | TRACE_ITER_OVERWRITE | |
331 | TRACE_ITER_IRQ_INFO; | |
4e655519 | 332 | |
b8de7bd1 | 333 | static int trace_stop_count; |
5389f6fa | 334 | static DEFINE_RAW_SPINLOCK(tracing_start_lock); |
b8de7bd1 | 335 | |
e7e2ee89 VN |
336 | static void wakeup_work_handler(struct work_struct *work) |
337 | { | |
338 | wake_up(&trace_wait); | |
339 | } | |
340 | ||
341 | static DECLARE_DELAYED_WORK(wakeup_work, wakeup_work_handler); | |
342 | ||
499e5470 SR |
343 | /** |
344 | * tracing_on - enable tracing buffers | |
345 | * | |
346 | * This function enables tracing buffers that may have been | |
347 | * disabled with tracing_off. | |
348 | */ | |
349 | void tracing_on(void) | |
350 | { | |
351 | if (global_trace.buffer) | |
352 | ring_buffer_record_on(global_trace.buffer); | |
353 | /* | |
354 | * This flag is only looked at when buffers haven't been | |
355 | * allocated yet. We don't really care about the race | |
356 | * between setting this flag and actually turning | |
357 | * on the buffer. | |
358 | */ | |
359 | global_trace.buffer_disabled = 0; | |
360 | } | |
361 | EXPORT_SYMBOL_GPL(tracing_on); | |
362 | ||
363 | /** | |
364 | * tracing_off - turn off tracing buffers | |
365 | * | |
366 | * This function stops the tracing buffers from recording data. | |
367 | * It does not disable any overhead the tracers themselves may | |
368 | * be causing. This function simply causes all recording to | |
369 | * the ring buffers to fail. | |
370 | */ | |
371 | void tracing_off(void) | |
372 | { | |
373 | if (global_trace.buffer) | |
374 | ring_buffer_record_on(global_trace.buffer); | |
375 | /* | |
376 | * This flag is only looked at when buffers haven't been | |
377 | * allocated yet. We don't really care about the race | |
378 | * between setting this flag and actually turning | |
379 | * on the buffer. | |
380 | */ | |
381 | global_trace.buffer_disabled = 1; | |
382 | } | |
383 | EXPORT_SYMBOL_GPL(tracing_off); | |
384 | ||
385 | /** | |
386 | * tracing_is_on - show state of ring buffers enabled | |
387 | */ | |
388 | int tracing_is_on(void) | |
389 | { | |
390 | if (global_trace.buffer) | |
391 | return ring_buffer_record_is_on(global_trace.buffer); | |
392 | return !global_trace.buffer_disabled; | |
393 | } | |
394 | EXPORT_SYMBOL_GPL(tracing_is_on); | |
395 | ||
4fcdae83 SR |
396 | /** |
397 | * trace_wake_up - wake up tasks waiting for trace input | |
398 | * | |
e7e2ee89 VN |
399 | * Schedules a delayed work to wake up any task that is blocked on the |
400 | * trace_wait queue. These is used with trace_poll for tasks polling the | |
401 | * trace. | |
4fcdae83 | 402 | */ |
4e655519 IM |
403 | void trace_wake_up(void) |
404 | { | |
e7e2ee89 | 405 | const unsigned long delay = msecs_to_jiffies(2); |
89f19f04 AM |
406 | |
407 | if (trace_flags & TRACE_ITER_BLOCK) | |
408 | return; | |
e7e2ee89 | 409 | schedule_delayed_work(&wakeup_work, delay); |
4e655519 | 410 | } |
bc0c38d1 | 411 | |
3928a8a2 | 412 | static int __init set_buf_size(char *str) |
bc0c38d1 | 413 | { |
3928a8a2 | 414 | unsigned long buf_size; |
c6caeeb1 | 415 | |
bc0c38d1 SR |
416 | if (!str) |
417 | return 0; | |
9d612bef | 418 | buf_size = memparse(str, &str); |
c6caeeb1 | 419 | /* nr_entries can not be zero */ |
9d612bef | 420 | if (buf_size == 0) |
c6caeeb1 | 421 | return 0; |
3928a8a2 | 422 | trace_buf_size = buf_size; |
bc0c38d1 SR |
423 | return 1; |
424 | } | |
3928a8a2 | 425 | __setup("trace_buf_size=", set_buf_size); |
bc0c38d1 | 426 | |
0e950173 TB |
427 | static int __init set_tracing_thresh(char *str) |
428 | { | |
429 | unsigned long threshhold; | |
430 | int ret; | |
431 | ||
432 | if (!str) | |
433 | return 0; | |
434 | ret = strict_strtoul(str, 0, &threshhold); | |
435 | if (ret < 0) | |
436 | return 0; | |
437 | tracing_thresh = threshhold * 1000; | |
438 | return 1; | |
439 | } | |
440 | __setup("tracing_thresh=", set_tracing_thresh); | |
441 | ||
57f50be1 SR |
442 | unsigned long nsecs_to_usecs(unsigned long nsecs) |
443 | { | |
444 | return nsecs / 1000; | |
445 | } | |
446 | ||
4fcdae83 | 447 | /* These must match the bit postions in trace_iterator_flags */ |
bc0c38d1 SR |
448 | static const char *trace_options[] = { |
449 | "print-parent", | |
450 | "sym-offset", | |
451 | "sym-addr", | |
452 | "verbose", | |
f9896bf3 | 453 | "raw", |
5e3ca0ec | 454 | "hex", |
cb0f12aa | 455 | "bin", |
2a2cc8f7 | 456 | "block", |
86387f7e | 457 | "stacktrace", |
5e1607a0 | 458 | "trace_printk", |
b2a866f9 | 459 | "ftrace_preempt", |
9f029e83 | 460 | "branch", |
12ef7d44 | 461 | "annotate", |
02b67518 | 462 | "userstacktrace", |
b54d3de9 | 463 | "sym-userobj", |
66896a85 | 464 | "printk-msg-only", |
c4a8e8be | 465 | "context-info", |
c032ef64 | 466 | "latency-format", |
be6f164a | 467 | "sleep-time", |
a2a16d6a | 468 | "graph-time", |
e870e9a1 | 469 | "record-cmd", |
750912fa | 470 | "overwrite", |
cf30cf67 | 471 | "disable_on_free", |
77271ce4 | 472 | "irq-info", |
bc0c38d1 SR |
473 | NULL |
474 | }; | |
475 | ||
5079f326 Z |
476 | static struct { |
477 | u64 (*func)(void); | |
478 | const char *name; | |
479 | } trace_clocks[] = { | |
480 | { trace_clock_local, "local" }, | |
481 | { trace_clock_global, "global" }, | |
6249687f | 482 | { trace_clock_counter, "counter" }, |
5079f326 Z |
483 | }; |
484 | ||
485 | int trace_clock_id; | |
486 | ||
b63f39ea | 487 | /* |
488 | * trace_parser_get_init - gets the buffer for trace parser | |
489 | */ | |
490 | int trace_parser_get_init(struct trace_parser *parser, int size) | |
491 | { | |
492 | memset(parser, 0, sizeof(*parser)); | |
493 | ||
494 | parser->buffer = kmalloc(size, GFP_KERNEL); | |
495 | if (!parser->buffer) | |
496 | return 1; | |
497 | ||
498 | parser->size = size; | |
499 | return 0; | |
500 | } | |
501 | ||
502 | /* | |
503 | * trace_parser_put - frees the buffer for trace parser | |
504 | */ | |
505 | void trace_parser_put(struct trace_parser *parser) | |
506 | { | |
507 | kfree(parser->buffer); | |
508 | } | |
509 | ||
510 | /* | |
511 | * trace_get_user - reads the user input string separated by space | |
512 | * (matched by isspace(ch)) | |
513 | * | |
514 | * For each string found the 'struct trace_parser' is updated, | |
515 | * and the function returns. | |
516 | * | |
517 | * Returns number of bytes read. | |
518 | * | |
519 | * See kernel/trace/trace.h for 'struct trace_parser' details. | |
520 | */ | |
521 | int trace_get_user(struct trace_parser *parser, const char __user *ubuf, | |
522 | size_t cnt, loff_t *ppos) | |
523 | { | |
524 | char ch; | |
525 | size_t read = 0; | |
526 | ssize_t ret; | |
527 | ||
528 | if (!*ppos) | |
529 | trace_parser_clear(parser); | |
530 | ||
531 | ret = get_user(ch, ubuf++); | |
532 | if (ret) | |
533 | goto out; | |
534 | ||
535 | read++; | |
536 | cnt--; | |
537 | ||
538 | /* | |
539 | * The parser is not finished with the last write, | |
540 | * continue reading the user input without skipping spaces. | |
541 | */ | |
542 | if (!parser->cont) { | |
543 | /* skip white space */ | |
544 | while (cnt && isspace(ch)) { | |
545 | ret = get_user(ch, ubuf++); | |
546 | if (ret) | |
547 | goto out; | |
548 | read++; | |
549 | cnt--; | |
550 | } | |
551 | ||
552 | /* only spaces were written */ | |
553 | if (isspace(ch)) { | |
554 | *ppos += read; | |
555 | ret = read; | |
556 | goto out; | |
557 | } | |
558 | ||
559 | parser->idx = 0; | |
560 | } | |
561 | ||
562 | /* read the non-space input */ | |
563 | while (cnt && !isspace(ch)) { | |
3c235a33 | 564 | if (parser->idx < parser->size - 1) |
b63f39ea | 565 | parser->buffer[parser->idx++] = ch; |
566 | else { | |
567 | ret = -EINVAL; | |
568 | goto out; | |
569 | } | |
570 | ret = get_user(ch, ubuf++); | |
571 | if (ret) | |
572 | goto out; | |
573 | read++; | |
574 | cnt--; | |
575 | } | |
576 | ||
577 | /* We either got finished input or we have to wait for another call. */ | |
578 | if (isspace(ch)) { | |
579 | parser->buffer[parser->idx] = 0; | |
580 | parser->cont = false; | |
581 | } else { | |
582 | parser->cont = true; | |
583 | parser->buffer[parser->idx++] = ch; | |
584 | } | |
585 | ||
586 | *ppos += read; | |
587 | ret = read; | |
588 | ||
589 | out: | |
590 | return ret; | |
591 | } | |
592 | ||
6c6c2796 PP |
593 | ssize_t trace_seq_to_user(struct trace_seq *s, char __user *ubuf, size_t cnt) |
594 | { | |
595 | int len; | |
596 | int ret; | |
597 | ||
2dc5d12b SR |
598 | if (!cnt) |
599 | return 0; | |
600 | ||
6c6c2796 PP |
601 | if (s->len <= s->readpos) |
602 | return -EBUSY; | |
603 | ||
604 | len = s->len - s->readpos; | |
605 | if (cnt > len) | |
606 | cnt = len; | |
607 | ret = copy_to_user(ubuf, s->buffer + s->readpos, cnt); | |
2dc5d12b | 608 | if (ret == cnt) |
6c6c2796 PP |
609 | return -EFAULT; |
610 | ||
2dc5d12b SR |
611 | cnt -= ret; |
612 | ||
e74da523 | 613 | s->readpos += cnt; |
6c6c2796 | 614 | return cnt; |
214023c3 SR |
615 | } |
616 | ||
b8b94265 | 617 | static ssize_t trace_seq_to_buffer(struct trace_seq *s, void *buf, size_t cnt) |
3c56819b EGM |
618 | { |
619 | int len; | |
3c56819b EGM |
620 | |
621 | if (s->len <= s->readpos) | |
622 | return -EBUSY; | |
623 | ||
624 | len = s->len - s->readpos; | |
625 | if (cnt > len) | |
626 | cnt = len; | |
5a26c8f0 | 627 | memcpy(buf, s->buffer + s->readpos, cnt); |
3c56819b | 628 | |
e74da523 | 629 | s->readpos += cnt; |
3c56819b EGM |
630 | return cnt; |
631 | } | |
632 | ||
5d4a9dba SR |
633 | /* |
634 | * ftrace_max_lock is used to protect the swapping of buffers | |
635 | * when taking a max snapshot. The buffers themselves are | |
636 | * protected by per_cpu spinlocks. But the action of the swap | |
637 | * needs its own lock. | |
638 | * | |
445c8951 | 639 | * This is defined as a arch_spinlock_t in order to help |
5d4a9dba SR |
640 | * with performance when lockdep debugging is enabled. |
641 | * | |
642 | * It is also used in other places outside the update_max_tr | |
643 | * so it needs to be defined outside of the | |
644 | * CONFIG_TRACER_MAX_TRACE. | |
645 | */ | |
445c8951 | 646 | static arch_spinlock_t ftrace_max_lock = |
edc35bd7 | 647 | (arch_spinlock_t)__ARCH_SPIN_LOCK_UNLOCKED; |
5d4a9dba | 648 | |
0e950173 TB |
649 | unsigned long __read_mostly tracing_thresh; |
650 | ||
5d4a9dba SR |
651 | #ifdef CONFIG_TRACER_MAX_TRACE |
652 | unsigned long __read_mostly tracing_max_latency; | |
5d4a9dba SR |
653 | |
654 | /* | |
655 | * Copy the new maximum trace into the separate maximum-trace | |
656 | * structure. (this way the maximum trace is permanently saved, | |
657 | * for later retrieval via /sys/kernel/debug/tracing/latency_trace) | |
658 | */ | |
659 | static void | |
660 | __update_max_tr(struct trace_array *tr, struct task_struct *tsk, int cpu) | |
661 | { | |
662 | struct trace_array_cpu *data = tr->data[cpu]; | |
1acaa1b2 | 663 | struct trace_array_cpu *max_data; |
5d4a9dba SR |
664 | |
665 | max_tr.cpu = cpu; | |
666 | max_tr.time_start = data->preempt_timestamp; | |
667 | ||
8248ac05 SR |
668 | max_data = max_tr.data[cpu]; |
669 | max_data->saved_latency = tracing_max_latency; | |
670 | max_data->critical_start = data->critical_start; | |
671 | max_data->critical_end = data->critical_end; | |
5d4a9dba | 672 | |
1acaa1b2 | 673 | memcpy(max_data->comm, tsk->comm, TASK_COMM_LEN); |
8248ac05 SR |
674 | max_data->pid = tsk->pid; |
675 | max_data->uid = task_uid(tsk); | |
676 | max_data->nice = tsk->static_prio - 20 - MAX_RT_PRIO; | |
677 | max_data->policy = tsk->policy; | |
678 | max_data->rt_priority = tsk->rt_priority; | |
5d4a9dba SR |
679 | |
680 | /* record this tasks comm */ | |
681 | tracing_record_cmdline(tsk); | |
682 | } | |
683 | ||
4fcdae83 SR |
684 | /** |
685 | * update_max_tr - snapshot all trace buffers from global_trace to max_tr | |
686 | * @tr: tracer | |
687 | * @tsk: the task with the latency | |
688 | * @cpu: The cpu that initiated the trace. | |
689 | * | |
690 | * Flip the buffers between the @tr and the max_tr and record information | |
691 | * about which task was the cause of this latency. | |
692 | */ | |
e309b41d | 693 | void |
bc0c38d1 SR |
694 | update_max_tr(struct trace_array *tr, struct task_struct *tsk, int cpu) |
695 | { | |
3928a8a2 | 696 | struct ring_buffer *buf = tr->buffer; |
bc0c38d1 | 697 | |
b8de7bd1 SR |
698 | if (trace_stop_count) |
699 | return; | |
700 | ||
4c11d7ae | 701 | WARN_ON_ONCE(!irqs_disabled()); |
ef710e10 KM |
702 | if (!current_trace->use_max_tr) { |
703 | WARN_ON_ONCE(1); | |
704 | return; | |
705 | } | |
0199c4e6 | 706 | arch_spin_lock(&ftrace_max_lock); |
3928a8a2 SR |
707 | |
708 | tr->buffer = max_tr.buffer; | |
709 | max_tr.buffer = buf; | |
710 | ||
bc0c38d1 | 711 | __update_max_tr(tr, tsk, cpu); |
0199c4e6 | 712 | arch_spin_unlock(&ftrace_max_lock); |
bc0c38d1 SR |
713 | } |
714 | ||
715 | /** | |
716 | * update_max_tr_single - only copy one trace over, and reset the rest | |
717 | * @tr - tracer | |
718 | * @tsk - task with the latency | |
719 | * @cpu - the cpu of the buffer to copy. | |
4fcdae83 SR |
720 | * |
721 | * Flip the trace of a single CPU buffer between the @tr and the max_tr. | |
bc0c38d1 | 722 | */ |
e309b41d | 723 | void |
bc0c38d1 SR |
724 | update_max_tr_single(struct trace_array *tr, struct task_struct *tsk, int cpu) |
725 | { | |
3928a8a2 | 726 | int ret; |
bc0c38d1 | 727 | |
b8de7bd1 SR |
728 | if (trace_stop_count) |
729 | return; | |
730 | ||
4c11d7ae | 731 | WARN_ON_ONCE(!irqs_disabled()); |
ef710e10 KM |
732 | if (!current_trace->use_max_tr) { |
733 | WARN_ON_ONCE(1); | |
734 | return; | |
735 | } | |
736 | ||
0199c4e6 | 737 | arch_spin_lock(&ftrace_max_lock); |
bc0c38d1 | 738 | |
3928a8a2 SR |
739 | ret = ring_buffer_swap_cpu(max_tr.buffer, tr->buffer, cpu); |
740 | ||
e8165dbb SR |
741 | if (ret == -EBUSY) { |
742 | /* | |
743 | * We failed to swap the buffer due to a commit taking | |
744 | * place on this CPU. We fail to record, but we reset | |
745 | * the max trace buffer (no one writes directly to it) | |
746 | * and flag that it failed. | |
747 | */ | |
748 | trace_array_printk(&max_tr, _THIS_IP_, | |
749 | "Failed to swap buffers due to commit in progress\n"); | |
750 | } | |
751 | ||
e8165dbb | 752 | WARN_ON_ONCE(ret && ret != -EAGAIN && ret != -EBUSY); |
bc0c38d1 SR |
753 | |
754 | __update_max_tr(tr, tsk, cpu); | |
0199c4e6 | 755 | arch_spin_unlock(&ftrace_max_lock); |
bc0c38d1 | 756 | } |
5d4a9dba | 757 | #endif /* CONFIG_TRACER_MAX_TRACE */ |
bc0c38d1 | 758 | |
4fcdae83 SR |
759 | /** |
760 | * register_tracer - register a tracer with the ftrace system. | |
761 | * @type - the plugin for the tracer | |
762 | * | |
763 | * Register a new plugin tracer. | |
764 | */ | |
bc0c38d1 SR |
765 | int register_tracer(struct tracer *type) |
766 | { | |
767 | struct tracer *t; | |
bc0c38d1 SR |
768 | int ret = 0; |
769 | ||
770 | if (!type->name) { | |
771 | pr_info("Tracer must have a name\n"); | |
772 | return -1; | |
773 | } | |
774 | ||
24a461d5 | 775 | if (strlen(type->name) >= MAX_TRACER_SIZE) { |
ee6c2c1b LZ |
776 | pr_info("Tracer has a name longer than %d\n", MAX_TRACER_SIZE); |
777 | return -1; | |
778 | } | |
779 | ||
bc0c38d1 | 780 | mutex_lock(&trace_types_lock); |
86fa2f60 | 781 | |
8e1b82e0 FW |
782 | tracing_selftest_running = true; |
783 | ||
bc0c38d1 SR |
784 | for (t = trace_types; t; t = t->next) { |
785 | if (strcmp(type->name, t->name) == 0) { | |
786 | /* already found */ | |
ee6c2c1b | 787 | pr_info("Tracer %s already registered\n", |
bc0c38d1 SR |
788 | type->name); |
789 | ret = -1; | |
790 | goto out; | |
791 | } | |
792 | } | |
793 | ||
adf9f195 FW |
794 | if (!type->set_flag) |
795 | type->set_flag = &dummy_set_flag; | |
796 | if (!type->flags) | |
797 | type->flags = &dummy_tracer_flags; | |
798 | else | |
799 | if (!type->flags->opts) | |
800 | type->flags->opts = dummy_tracer_opt; | |
6eaaa5d5 FW |
801 | if (!type->wait_pipe) |
802 | type->wait_pipe = default_wait_pipe; | |
803 | ||
adf9f195 | 804 | |
60a11774 | 805 | #ifdef CONFIG_FTRACE_STARTUP_TEST |
b2821ae6 | 806 | if (type->selftest && !tracing_selftest_disabled) { |
60a11774 | 807 | struct tracer *saved_tracer = current_trace; |
60a11774 | 808 | struct trace_array *tr = &global_trace; |
ff32504f | 809 | |
60a11774 SR |
810 | /* |
811 | * Run a selftest on this tracer. | |
812 | * Here we reset the trace buffer, and set the current | |
813 | * tracer to be this tracer. The tracer can then run some | |
814 | * internal tracing to verify that everything is in order. | |
815 | * If we fail, we do not register this tracer. | |
816 | */ | |
76f0d073 | 817 | tracing_reset_online_cpus(tr); |
86fa2f60 | 818 | |
60a11774 | 819 | current_trace = type; |
4a0b1665 SR |
820 | |
821 | /* If we expanded the buffers, make sure the max is expanded too */ | |
822 | if (ring_buffer_expanded && type->use_max_tr) | |
438ced17 VN |
823 | ring_buffer_resize(max_tr.buffer, trace_buf_size, |
824 | RING_BUFFER_ALL_CPUS); | |
4a0b1665 | 825 | |
60a11774 SR |
826 | /* the test is responsible for initializing and enabling */ |
827 | pr_info("Testing tracer %s: ", type->name); | |
828 | ret = type->selftest(type, tr); | |
829 | /* the test is responsible for resetting too */ | |
830 | current_trace = saved_tracer; | |
60a11774 SR |
831 | if (ret) { |
832 | printk(KERN_CONT "FAILED!\n"); | |
833 | goto out; | |
834 | } | |
1d4db00a | 835 | /* Only reset on passing, to avoid touching corrupted buffers */ |
76f0d073 | 836 | tracing_reset_online_cpus(tr); |
86fa2f60 | 837 | |
4a0b1665 SR |
838 | /* Shrink the max buffer again */ |
839 | if (ring_buffer_expanded && type->use_max_tr) | |
438ced17 VN |
840 | ring_buffer_resize(max_tr.buffer, 1, |
841 | RING_BUFFER_ALL_CPUS); | |
4a0b1665 | 842 | |
60a11774 SR |
843 | printk(KERN_CONT "PASSED\n"); |
844 | } | |
845 | #endif | |
846 | ||
bc0c38d1 SR |
847 | type->next = trace_types; |
848 | trace_types = type; | |
60a11774 | 849 | |
bc0c38d1 | 850 | out: |
8e1b82e0 | 851 | tracing_selftest_running = false; |
bc0c38d1 SR |
852 | mutex_unlock(&trace_types_lock); |
853 | ||
dac74940 SR |
854 | if (ret || !default_bootup_tracer) |
855 | goto out_unlock; | |
856 | ||
ee6c2c1b | 857 | if (strncmp(default_bootup_tracer, type->name, MAX_TRACER_SIZE)) |
dac74940 SR |
858 | goto out_unlock; |
859 | ||
860 | printk(KERN_INFO "Starting tracer '%s'\n", type->name); | |
861 | /* Do we want this tracer to start on bootup? */ | |
862 | tracing_set_tracer(type->name); | |
863 | default_bootup_tracer = NULL; | |
864 | /* disable other selftests, since this will break it. */ | |
865 | tracing_selftest_disabled = 1; | |
b2821ae6 | 866 | #ifdef CONFIG_FTRACE_STARTUP_TEST |
dac74940 SR |
867 | printk(KERN_INFO "Disabling FTRACE selftests due to running tracer '%s'\n", |
868 | type->name); | |
b2821ae6 | 869 | #endif |
b2821ae6 | 870 | |
dac74940 | 871 | out_unlock: |
bc0c38d1 SR |
872 | return ret; |
873 | } | |
874 | ||
875 | void unregister_tracer(struct tracer *type) | |
876 | { | |
877 | struct tracer **t; | |
bc0c38d1 SR |
878 | |
879 | mutex_lock(&trace_types_lock); | |
880 | for (t = &trace_types; *t; t = &(*t)->next) { | |
881 | if (*t == type) | |
882 | goto found; | |
883 | } | |
ee6c2c1b | 884 | pr_info("Tracer %s not registered\n", type->name); |
bc0c38d1 SR |
885 | goto out; |
886 | ||
887 | found: | |
888 | *t = (*t)->next; | |
b5db03c4 ACM |
889 | |
890 | if (type == current_trace && tracer_enabled) { | |
891 | tracer_enabled = 0; | |
892 | tracing_stop(); | |
893 | if (current_trace->stop) | |
894 | current_trace->stop(&global_trace); | |
895 | current_trace = &nop_trace; | |
896 | } | |
ee6c2c1b | 897 | out: |
bc0c38d1 SR |
898 | mutex_unlock(&trace_types_lock); |
899 | } | |
900 | ||
f633903a SR |
901 | void tracing_reset(struct trace_array *tr, int cpu) |
902 | { | |
903 | struct ring_buffer *buffer = tr->buffer; | |
904 | ||
905 | ring_buffer_record_disable(buffer); | |
906 | ||
907 | /* Make sure all commits have finished */ | |
908 | synchronize_sched(); | |
68179686 | 909 | ring_buffer_reset_cpu(buffer, cpu); |
f633903a SR |
910 | |
911 | ring_buffer_record_enable(buffer); | |
912 | } | |
913 | ||
213cc060 PE |
914 | void tracing_reset_online_cpus(struct trace_array *tr) |
915 | { | |
621968cd | 916 | struct ring_buffer *buffer = tr->buffer; |
213cc060 PE |
917 | int cpu; |
918 | ||
621968cd SR |
919 | ring_buffer_record_disable(buffer); |
920 | ||
921 | /* Make sure all commits have finished */ | |
922 | synchronize_sched(); | |
923 | ||
213cc060 PE |
924 | tr->time_start = ftrace_now(tr->cpu); |
925 | ||
926 | for_each_online_cpu(cpu) | |
68179686 | 927 | ring_buffer_reset_cpu(buffer, cpu); |
621968cd SR |
928 | |
929 | ring_buffer_record_enable(buffer); | |
213cc060 PE |
930 | } |
931 | ||
9456f0fa SR |
932 | void tracing_reset_current(int cpu) |
933 | { | |
934 | tracing_reset(&global_trace, cpu); | |
935 | } | |
936 | ||
937 | void tracing_reset_current_online_cpus(void) | |
938 | { | |
939 | tracing_reset_online_cpus(&global_trace); | |
940 | } | |
941 | ||
bc0c38d1 | 942 | #define SAVED_CMDLINES 128 |
2c7eea4c | 943 | #define NO_CMDLINE_MAP UINT_MAX |
bc0c38d1 SR |
944 | static unsigned map_pid_to_cmdline[PID_MAX_DEFAULT+1]; |
945 | static unsigned map_cmdline_to_pid[SAVED_CMDLINES]; | |
946 | static char saved_cmdlines[SAVED_CMDLINES][TASK_COMM_LEN]; | |
947 | static int cmdline_idx; | |
edc35bd7 | 948 | static arch_spinlock_t trace_cmdline_lock = __ARCH_SPIN_LOCK_UNLOCKED; |
25b0b44a | 949 | |
25b0b44a | 950 | /* temporary disable recording */ |
4fd27358 | 951 | static atomic_t trace_record_cmdline_disabled __read_mostly; |
bc0c38d1 SR |
952 | |
953 | static void trace_init_cmdlines(void) | |
954 | { | |
2c7eea4c TG |
955 | memset(&map_pid_to_cmdline, NO_CMDLINE_MAP, sizeof(map_pid_to_cmdline)); |
956 | memset(&map_cmdline_to_pid, NO_CMDLINE_MAP, sizeof(map_cmdline_to_pid)); | |
bc0c38d1 SR |
957 | cmdline_idx = 0; |
958 | } | |
959 | ||
b5130b1e CE |
960 | int is_tracing_stopped(void) |
961 | { | |
962 | return trace_stop_count; | |
963 | } | |
964 | ||
69bb54ec SR |
965 | /** |
966 | * ftrace_off_permanent - disable all ftrace code permanently | |
967 | * | |
968 | * This should only be called when a serious anomally has | |
969 | * been detected. This will turn off the function tracing, | |
970 | * ring buffers, and other tracing utilites. It takes no | |
971 | * locks and can be called from any context. | |
972 | */ | |
973 | void ftrace_off_permanent(void) | |
974 | { | |
975 | tracing_disabled = 1; | |
976 | ftrace_stop(); | |
977 | tracing_off_permanent(); | |
978 | } | |
979 | ||
0f048701 SR |
980 | /** |
981 | * tracing_start - quick start of the tracer | |
982 | * | |
983 | * If tracing is enabled but was stopped by tracing_stop, | |
984 | * this will start the tracer back up. | |
985 | */ | |
986 | void tracing_start(void) | |
987 | { | |
988 | struct ring_buffer *buffer; | |
989 | unsigned long flags; | |
990 | ||
991 | if (tracing_disabled) | |
992 | return; | |
993 | ||
5389f6fa | 994 | raw_spin_lock_irqsave(&tracing_start_lock, flags); |
b06a8301 SR |
995 | if (--trace_stop_count) { |
996 | if (trace_stop_count < 0) { | |
997 | /* Someone screwed up their debugging */ | |
998 | WARN_ON_ONCE(1); | |
999 | trace_stop_count = 0; | |
1000 | } | |
0f048701 SR |
1001 | goto out; |
1002 | } | |
1003 | ||
a2f80714 SR |
1004 | /* Prevent the buffers from switching */ |
1005 | arch_spin_lock(&ftrace_max_lock); | |
0f048701 SR |
1006 | |
1007 | buffer = global_trace.buffer; | |
1008 | if (buffer) | |
1009 | ring_buffer_record_enable(buffer); | |
1010 | ||
1011 | buffer = max_tr.buffer; | |
1012 | if (buffer) | |
1013 | ring_buffer_record_enable(buffer); | |
1014 | ||
a2f80714 SR |
1015 | arch_spin_unlock(&ftrace_max_lock); |
1016 | ||
0f048701 SR |
1017 | ftrace_start(); |
1018 | out: | |
5389f6fa | 1019 | raw_spin_unlock_irqrestore(&tracing_start_lock, flags); |
0f048701 SR |
1020 | } |
1021 | ||
1022 | /** | |
1023 | * tracing_stop - quick stop of the tracer | |
1024 | * | |
1025 | * Light weight way to stop tracing. Use in conjunction with | |
1026 | * tracing_start. | |
1027 | */ | |
1028 | void tracing_stop(void) | |
1029 | { | |
1030 | struct ring_buffer *buffer; | |
1031 | unsigned long flags; | |
1032 | ||
1033 | ftrace_stop(); | |
5389f6fa | 1034 | raw_spin_lock_irqsave(&tracing_start_lock, flags); |
0f048701 SR |
1035 | if (trace_stop_count++) |
1036 | goto out; | |
1037 | ||
a2f80714 SR |
1038 | /* Prevent the buffers from switching */ |
1039 | arch_spin_lock(&ftrace_max_lock); | |
1040 | ||
0f048701 SR |
1041 | buffer = global_trace.buffer; |
1042 | if (buffer) | |
1043 | ring_buffer_record_disable(buffer); | |
1044 | ||
1045 | buffer = max_tr.buffer; | |
1046 | if (buffer) | |
1047 | ring_buffer_record_disable(buffer); | |
1048 | ||
a2f80714 SR |
1049 | arch_spin_unlock(&ftrace_max_lock); |
1050 | ||
0f048701 | 1051 | out: |
5389f6fa | 1052 | raw_spin_unlock_irqrestore(&tracing_start_lock, flags); |
0f048701 SR |
1053 | } |
1054 | ||
e309b41d | 1055 | void trace_stop_cmdline_recording(void); |
bc0c38d1 | 1056 | |
e309b41d | 1057 | static void trace_save_cmdline(struct task_struct *tsk) |
bc0c38d1 | 1058 | { |
a635cf04 | 1059 | unsigned pid, idx; |
bc0c38d1 SR |
1060 | |
1061 | if (!tsk->pid || unlikely(tsk->pid > PID_MAX_DEFAULT)) | |
1062 | return; | |
1063 | ||
1064 | /* | |
1065 | * It's not the end of the world if we don't get | |
1066 | * the lock, but we also don't want to spin | |
1067 | * nor do we want to disable interrupts, | |
1068 | * so if we miss here, then better luck next time. | |
1069 | */ | |
0199c4e6 | 1070 | if (!arch_spin_trylock(&trace_cmdline_lock)) |
bc0c38d1 SR |
1071 | return; |
1072 | ||
1073 | idx = map_pid_to_cmdline[tsk->pid]; | |
2c7eea4c | 1074 | if (idx == NO_CMDLINE_MAP) { |
bc0c38d1 SR |
1075 | idx = (cmdline_idx + 1) % SAVED_CMDLINES; |
1076 | ||
a635cf04 CE |
1077 | /* |
1078 | * Check whether the cmdline buffer at idx has a pid | |
1079 | * mapped. We are going to overwrite that entry so we | |
1080 | * need to clear the map_pid_to_cmdline. Otherwise we | |
1081 | * would read the new comm for the old pid. | |
1082 | */ | |
1083 | pid = map_cmdline_to_pid[idx]; | |
1084 | if (pid != NO_CMDLINE_MAP) | |
1085 | map_pid_to_cmdline[pid] = NO_CMDLINE_MAP; | |
bc0c38d1 | 1086 | |
a635cf04 | 1087 | map_cmdline_to_pid[idx] = tsk->pid; |
bc0c38d1 SR |
1088 | map_pid_to_cmdline[tsk->pid] = idx; |
1089 | ||
1090 | cmdline_idx = idx; | |
1091 | } | |
1092 | ||
1093 | memcpy(&saved_cmdlines[idx], tsk->comm, TASK_COMM_LEN); | |
1094 | ||
0199c4e6 | 1095 | arch_spin_unlock(&trace_cmdline_lock); |
bc0c38d1 SR |
1096 | } |
1097 | ||
4ca53085 | 1098 | void trace_find_cmdline(int pid, char comm[]) |
bc0c38d1 | 1099 | { |
bc0c38d1 SR |
1100 | unsigned map; |
1101 | ||
4ca53085 SR |
1102 | if (!pid) { |
1103 | strcpy(comm, "<idle>"); | |
1104 | return; | |
1105 | } | |
bc0c38d1 | 1106 | |
74bf4076 SR |
1107 | if (WARN_ON_ONCE(pid < 0)) { |
1108 | strcpy(comm, "<XXX>"); | |
1109 | return; | |
1110 | } | |
1111 | ||
4ca53085 SR |
1112 | if (pid > PID_MAX_DEFAULT) { |
1113 | strcpy(comm, "<...>"); | |
1114 | return; | |
1115 | } | |
bc0c38d1 | 1116 | |
5b6045a9 | 1117 | preempt_disable(); |
0199c4e6 | 1118 | arch_spin_lock(&trace_cmdline_lock); |
bc0c38d1 | 1119 | map = map_pid_to_cmdline[pid]; |
50d88758 TG |
1120 | if (map != NO_CMDLINE_MAP) |
1121 | strcpy(comm, saved_cmdlines[map]); | |
1122 | else | |
1123 | strcpy(comm, "<...>"); | |
bc0c38d1 | 1124 | |
0199c4e6 | 1125 | arch_spin_unlock(&trace_cmdline_lock); |
5b6045a9 | 1126 | preempt_enable(); |
bc0c38d1 SR |
1127 | } |
1128 | ||
e309b41d | 1129 | void tracing_record_cmdline(struct task_struct *tsk) |
bc0c38d1 | 1130 | { |
18aecd36 TG |
1131 | if (atomic_read(&trace_record_cmdline_disabled) || !tracer_enabled || |
1132 | !tracing_is_on()) | |
bc0c38d1 SR |
1133 | return; |
1134 | ||
1135 | trace_save_cmdline(tsk); | |
1136 | } | |
1137 | ||
45dcd8b8 | 1138 | void |
38697053 SR |
1139 | tracing_generic_entry_update(struct trace_entry *entry, unsigned long flags, |
1140 | int pc) | |
bc0c38d1 SR |
1141 | { |
1142 | struct task_struct *tsk = current; | |
bc0c38d1 | 1143 | |
777e208d SR |
1144 | entry->preempt_count = pc & 0xff; |
1145 | entry->pid = (tsk) ? tsk->pid : 0; | |
a3a4a5ac | 1146 | entry->padding = 0; |
777e208d | 1147 | entry->flags = |
9244489a | 1148 | #ifdef CONFIG_TRACE_IRQFLAGS_SUPPORT |
2e2ca155 | 1149 | (irqs_disabled_flags(flags) ? TRACE_FLAG_IRQS_OFF : 0) | |
9244489a SR |
1150 | #else |
1151 | TRACE_FLAG_IRQS_NOSUPPORT | | |
1152 | #endif | |
bc0c38d1 SR |
1153 | ((pc & HARDIRQ_MASK) ? TRACE_FLAG_HARDIRQ : 0) | |
1154 | ((pc & SOFTIRQ_MASK) ? TRACE_FLAG_SOFTIRQ : 0) | | |
1155 | (need_resched() ? TRACE_FLAG_NEED_RESCHED : 0); | |
1156 | } | |
f413cdb8 | 1157 | EXPORT_SYMBOL_GPL(tracing_generic_entry_update); |
bc0c38d1 | 1158 | |
e77405ad SR |
1159 | struct ring_buffer_event * |
1160 | trace_buffer_lock_reserve(struct ring_buffer *buffer, | |
1161 | int type, | |
1162 | unsigned long len, | |
1163 | unsigned long flags, int pc) | |
51a763dd ACM |
1164 | { |
1165 | struct ring_buffer_event *event; | |
1166 | ||
e77405ad | 1167 | event = ring_buffer_lock_reserve(buffer, len); |
51a763dd ACM |
1168 | if (event != NULL) { |
1169 | struct trace_entry *ent = ring_buffer_event_data(event); | |
1170 | ||
1171 | tracing_generic_entry_update(ent, flags, pc); | |
1172 | ent->type = type; | |
1173 | } | |
1174 | ||
1175 | return event; | |
1176 | } | |
51a763dd | 1177 | |
e77405ad SR |
1178 | static inline void |
1179 | __trace_buffer_unlock_commit(struct ring_buffer *buffer, | |
1180 | struct ring_buffer_event *event, | |
1181 | unsigned long flags, int pc, | |
1182 | int wake) | |
51a763dd | 1183 | { |
e77405ad | 1184 | ring_buffer_unlock_commit(buffer, event); |
51a763dd | 1185 | |
e77405ad SR |
1186 | ftrace_trace_stack(buffer, flags, 6, pc); |
1187 | ftrace_trace_userstack(buffer, flags, pc); | |
07edf712 FW |
1188 | |
1189 | if (wake) | |
1190 | trace_wake_up(); | |
1191 | } | |
1192 | ||
e77405ad SR |
1193 | void trace_buffer_unlock_commit(struct ring_buffer *buffer, |
1194 | struct ring_buffer_event *event, | |
1195 | unsigned long flags, int pc) | |
07edf712 | 1196 | { |
e77405ad | 1197 | __trace_buffer_unlock_commit(buffer, event, flags, pc, 1); |
51a763dd ACM |
1198 | } |
1199 | ||
ef5580d0 | 1200 | struct ring_buffer_event * |
e77405ad SR |
1201 | trace_current_buffer_lock_reserve(struct ring_buffer **current_rb, |
1202 | int type, unsigned long len, | |
ef5580d0 SR |
1203 | unsigned long flags, int pc) |
1204 | { | |
e77405ad SR |
1205 | *current_rb = global_trace.buffer; |
1206 | return trace_buffer_lock_reserve(*current_rb, | |
ef5580d0 SR |
1207 | type, len, flags, pc); |
1208 | } | |
94487d6d | 1209 | EXPORT_SYMBOL_GPL(trace_current_buffer_lock_reserve); |
ef5580d0 | 1210 | |
e77405ad SR |
1211 | void trace_current_buffer_unlock_commit(struct ring_buffer *buffer, |
1212 | struct ring_buffer_event *event, | |
ef5580d0 SR |
1213 | unsigned long flags, int pc) |
1214 | { | |
e77405ad | 1215 | __trace_buffer_unlock_commit(buffer, event, flags, pc, 1); |
07edf712 | 1216 | } |
94487d6d | 1217 | EXPORT_SYMBOL_GPL(trace_current_buffer_unlock_commit); |
07edf712 | 1218 | |
e77405ad SR |
1219 | void trace_nowake_buffer_unlock_commit(struct ring_buffer *buffer, |
1220 | struct ring_buffer_event *event, | |
1221 | unsigned long flags, int pc) | |
07edf712 | 1222 | { |
e77405ad | 1223 | __trace_buffer_unlock_commit(buffer, event, flags, pc, 0); |
77d9f465 | 1224 | } |
94487d6d | 1225 | EXPORT_SYMBOL_GPL(trace_nowake_buffer_unlock_commit); |
77d9f465 | 1226 | |
1fd8df2c MH |
1227 | void trace_nowake_buffer_unlock_commit_regs(struct ring_buffer *buffer, |
1228 | struct ring_buffer_event *event, | |
1229 | unsigned long flags, int pc, | |
1230 | struct pt_regs *regs) | |
1231 | { | |
1232 | ring_buffer_unlock_commit(buffer, event); | |
1233 | ||
1234 | ftrace_trace_stack_regs(buffer, flags, 0, pc, regs); | |
1235 | ftrace_trace_userstack(buffer, flags, pc); | |
1236 | } | |
1237 | EXPORT_SYMBOL_GPL(trace_nowake_buffer_unlock_commit_regs); | |
1238 | ||
e77405ad SR |
1239 | void trace_current_buffer_discard_commit(struct ring_buffer *buffer, |
1240 | struct ring_buffer_event *event) | |
77d9f465 | 1241 | { |
e77405ad | 1242 | ring_buffer_discard_commit(buffer, event); |
ef5580d0 | 1243 | } |
12acd473 | 1244 | EXPORT_SYMBOL_GPL(trace_current_buffer_discard_commit); |
ef5580d0 | 1245 | |
e309b41d | 1246 | void |
7be42151 | 1247 | trace_function(struct trace_array *tr, |
38697053 SR |
1248 | unsigned long ip, unsigned long parent_ip, unsigned long flags, |
1249 | int pc) | |
bc0c38d1 | 1250 | { |
e1112b4d | 1251 | struct ftrace_event_call *call = &event_function; |
e77405ad | 1252 | struct ring_buffer *buffer = tr->buffer; |
3928a8a2 | 1253 | struct ring_buffer_event *event; |
777e208d | 1254 | struct ftrace_entry *entry; |
bc0c38d1 | 1255 | |
d769041f | 1256 | /* If we are reading the ring buffer, don't trace */ |
dd17c8f7 | 1257 | if (unlikely(__this_cpu_read(ftrace_cpu_disabled))) |
d769041f SR |
1258 | return; |
1259 | ||
e77405ad | 1260 | event = trace_buffer_lock_reserve(buffer, TRACE_FN, sizeof(*entry), |
51a763dd | 1261 | flags, pc); |
3928a8a2 SR |
1262 | if (!event) |
1263 | return; | |
1264 | entry = ring_buffer_event_data(event); | |
777e208d SR |
1265 | entry->ip = ip; |
1266 | entry->parent_ip = parent_ip; | |
e1112b4d | 1267 | |
e77405ad SR |
1268 | if (!filter_check_discard(call, entry, buffer, event)) |
1269 | ring_buffer_unlock_commit(buffer, event); | |
bc0c38d1 SR |
1270 | } |
1271 | ||
e309b41d | 1272 | void |
2e0f5761 | 1273 | ftrace(struct trace_array *tr, struct trace_array_cpu *data, |
38697053 SR |
1274 | unsigned long ip, unsigned long parent_ip, unsigned long flags, |
1275 | int pc) | |
2e0f5761 IM |
1276 | { |
1277 | if (likely(!atomic_read(&data->disabled))) | |
7be42151 | 1278 | trace_function(tr, ip, parent_ip, flags, pc); |
2e0f5761 IM |
1279 | } |
1280 | ||
c0a0d0d3 | 1281 | #ifdef CONFIG_STACKTRACE |
4a9bd3f1 SR |
1282 | |
1283 | #define FTRACE_STACK_MAX_ENTRIES (PAGE_SIZE / sizeof(unsigned long)) | |
1284 | struct ftrace_stack { | |
1285 | unsigned long calls[FTRACE_STACK_MAX_ENTRIES]; | |
1286 | }; | |
1287 | ||
1288 | static DEFINE_PER_CPU(struct ftrace_stack, ftrace_stack); | |
1289 | static DEFINE_PER_CPU(int, ftrace_stack_reserve); | |
1290 | ||
e77405ad | 1291 | static void __ftrace_trace_stack(struct ring_buffer *buffer, |
53614991 | 1292 | unsigned long flags, |
1fd8df2c | 1293 | int skip, int pc, struct pt_regs *regs) |
86387f7e | 1294 | { |
e1112b4d | 1295 | struct ftrace_event_call *call = &event_kernel_stack; |
3928a8a2 | 1296 | struct ring_buffer_event *event; |
777e208d | 1297 | struct stack_entry *entry; |
86387f7e | 1298 | struct stack_trace trace; |
4a9bd3f1 SR |
1299 | int use_stack; |
1300 | int size = FTRACE_STACK_ENTRIES; | |
1301 | ||
1302 | trace.nr_entries = 0; | |
1303 | trace.skip = skip; | |
1304 | ||
1305 | /* | |
1306 | * Since events can happen in NMIs there's no safe way to | |
1307 | * use the per cpu ftrace_stacks. We reserve it and if an interrupt | |
1308 | * or NMI comes in, it will just have to use the default | |
1309 | * FTRACE_STACK_SIZE. | |
1310 | */ | |
1311 | preempt_disable_notrace(); | |
1312 | ||
1313 | use_stack = ++__get_cpu_var(ftrace_stack_reserve); | |
1314 | /* | |
1315 | * We don't need any atomic variables, just a barrier. | |
1316 | * If an interrupt comes in, we don't care, because it would | |
1317 | * have exited and put the counter back to what we want. | |
1318 | * We just need a barrier to keep gcc from moving things | |
1319 | * around. | |
1320 | */ | |
1321 | barrier(); | |
1322 | if (use_stack == 1) { | |
1323 | trace.entries = &__get_cpu_var(ftrace_stack).calls[0]; | |
1324 | trace.max_entries = FTRACE_STACK_MAX_ENTRIES; | |
1325 | ||
1326 | if (regs) | |
1327 | save_stack_trace_regs(regs, &trace); | |
1328 | else | |
1329 | save_stack_trace(&trace); | |
1330 | ||
1331 | if (trace.nr_entries > size) | |
1332 | size = trace.nr_entries; | |
1333 | } else | |
1334 | /* From now on, use_stack is a boolean */ | |
1335 | use_stack = 0; | |
1336 | ||
1337 | size *= sizeof(unsigned long); | |
86387f7e | 1338 | |
e77405ad | 1339 | event = trace_buffer_lock_reserve(buffer, TRACE_STACK, |
4a9bd3f1 | 1340 | sizeof(*entry) + size, flags, pc); |
3928a8a2 | 1341 | if (!event) |
4a9bd3f1 SR |
1342 | goto out; |
1343 | entry = ring_buffer_event_data(event); | |
86387f7e | 1344 | |
4a9bd3f1 SR |
1345 | memset(&entry->caller, 0, size); |
1346 | ||
1347 | if (use_stack) | |
1348 | memcpy(&entry->caller, trace.entries, | |
1349 | trace.nr_entries * sizeof(unsigned long)); | |
1350 | else { | |
1351 | trace.max_entries = FTRACE_STACK_ENTRIES; | |
1352 | trace.entries = entry->caller; | |
1353 | if (regs) | |
1354 | save_stack_trace_regs(regs, &trace); | |
1355 | else | |
1356 | save_stack_trace(&trace); | |
1357 | } | |
1358 | ||
1359 | entry->size = trace.nr_entries; | |
86387f7e | 1360 | |
e77405ad SR |
1361 | if (!filter_check_discard(call, entry, buffer, event)) |
1362 | ring_buffer_unlock_commit(buffer, event); | |
4a9bd3f1 SR |
1363 | |
1364 | out: | |
1365 | /* Again, don't let gcc optimize things here */ | |
1366 | barrier(); | |
1367 | __get_cpu_var(ftrace_stack_reserve)--; | |
1368 | preempt_enable_notrace(); | |
1369 | ||
f0a920d5 IM |
1370 | } |
1371 | ||
1fd8df2c MH |
1372 | void ftrace_trace_stack_regs(struct ring_buffer *buffer, unsigned long flags, |
1373 | int skip, int pc, struct pt_regs *regs) | |
1374 | { | |
1375 | if (!(trace_flags & TRACE_ITER_STACKTRACE)) | |
1376 | return; | |
1377 | ||
1378 | __ftrace_trace_stack(buffer, flags, skip, pc, regs); | |
1379 | } | |
1380 | ||
e77405ad SR |
1381 | void ftrace_trace_stack(struct ring_buffer *buffer, unsigned long flags, |
1382 | int skip, int pc) | |
53614991 SR |
1383 | { |
1384 | if (!(trace_flags & TRACE_ITER_STACKTRACE)) | |
1385 | return; | |
1386 | ||
1fd8df2c | 1387 | __ftrace_trace_stack(buffer, flags, skip, pc, NULL); |
53614991 SR |
1388 | } |
1389 | ||
c0a0d0d3 FW |
1390 | void __trace_stack(struct trace_array *tr, unsigned long flags, int skip, |
1391 | int pc) | |
38697053 | 1392 | { |
1fd8df2c | 1393 | __ftrace_trace_stack(tr->buffer, flags, skip, pc, NULL); |
38697053 SR |
1394 | } |
1395 | ||
03889384 SR |
1396 | /** |
1397 | * trace_dump_stack - record a stack back trace in the trace buffer | |
1398 | */ | |
1399 | void trace_dump_stack(void) | |
1400 | { | |
1401 | unsigned long flags; | |
1402 | ||
1403 | if (tracing_disabled || tracing_selftest_running) | |
e36c5458 | 1404 | return; |
03889384 SR |
1405 | |
1406 | local_save_flags(flags); | |
1407 | ||
1408 | /* skipping 3 traces, seems to get us at the caller of this function */ | |
1fd8df2c | 1409 | __ftrace_trace_stack(global_trace.buffer, flags, 3, preempt_count(), NULL); |
03889384 SR |
1410 | } |
1411 | ||
91e86e56 SR |
1412 | static DEFINE_PER_CPU(int, user_stack_count); |
1413 | ||
e77405ad SR |
1414 | void |
1415 | ftrace_trace_userstack(struct ring_buffer *buffer, unsigned long flags, int pc) | |
02b67518 | 1416 | { |
e1112b4d | 1417 | struct ftrace_event_call *call = &event_user_stack; |
8d7c6a96 | 1418 | struct ring_buffer_event *event; |
02b67518 TE |
1419 | struct userstack_entry *entry; |
1420 | struct stack_trace trace; | |
02b67518 TE |
1421 | |
1422 | if (!(trace_flags & TRACE_ITER_USERSTACKTRACE)) | |
1423 | return; | |
1424 | ||
b6345879 SR |
1425 | /* |
1426 | * NMIs can not handle page faults, even with fix ups. | |
1427 | * The save user stack can (and often does) fault. | |
1428 | */ | |
1429 | if (unlikely(in_nmi())) | |
1430 | return; | |
02b67518 | 1431 | |
91e86e56 SR |
1432 | /* |
1433 | * prevent recursion, since the user stack tracing may | |
1434 | * trigger other kernel events. | |
1435 | */ | |
1436 | preempt_disable(); | |
1437 | if (__this_cpu_read(user_stack_count)) | |
1438 | goto out; | |
1439 | ||
1440 | __this_cpu_inc(user_stack_count); | |
1441 | ||
e77405ad | 1442 | event = trace_buffer_lock_reserve(buffer, TRACE_USER_STACK, |
51a763dd | 1443 | sizeof(*entry), flags, pc); |
02b67518 | 1444 | if (!event) |
1dbd1951 | 1445 | goto out_drop_count; |
02b67518 | 1446 | entry = ring_buffer_event_data(event); |
02b67518 | 1447 | |
48659d31 | 1448 | entry->tgid = current->tgid; |
02b67518 TE |
1449 | memset(&entry->caller, 0, sizeof(entry->caller)); |
1450 | ||
1451 | trace.nr_entries = 0; | |
1452 | trace.max_entries = FTRACE_STACK_ENTRIES; | |
1453 | trace.skip = 0; | |
1454 | trace.entries = entry->caller; | |
1455 | ||
1456 | save_stack_trace_user(&trace); | |
e77405ad SR |
1457 | if (!filter_check_discard(call, entry, buffer, event)) |
1458 | ring_buffer_unlock_commit(buffer, event); | |
91e86e56 | 1459 | |
1dbd1951 | 1460 | out_drop_count: |
91e86e56 | 1461 | __this_cpu_dec(user_stack_count); |
91e86e56 SR |
1462 | out: |
1463 | preempt_enable(); | |
02b67518 TE |
1464 | } |
1465 | ||
4fd27358 HE |
1466 | #ifdef UNUSED |
1467 | static void __trace_userstack(struct trace_array *tr, unsigned long flags) | |
02b67518 | 1468 | { |
7be42151 | 1469 | ftrace_trace_userstack(tr, flags, preempt_count()); |
02b67518 | 1470 | } |
4fd27358 | 1471 | #endif /* UNUSED */ |
02b67518 | 1472 | |
c0a0d0d3 FW |
1473 | #endif /* CONFIG_STACKTRACE */ |
1474 | ||
07d777fe SR |
1475 | /* created for use with alloc_percpu */ |
1476 | struct trace_buffer_struct { | |
1477 | char buffer[TRACE_BUF_SIZE]; | |
1478 | }; | |
1479 | ||
1480 | static struct trace_buffer_struct *trace_percpu_buffer; | |
1481 | static struct trace_buffer_struct *trace_percpu_sirq_buffer; | |
1482 | static struct trace_buffer_struct *trace_percpu_irq_buffer; | |
1483 | static struct trace_buffer_struct *trace_percpu_nmi_buffer; | |
1484 | ||
1485 | /* | |
1486 | * The buffer used is dependent on the context. There is a per cpu | |
1487 | * buffer for normal context, softirq contex, hard irq context and | |
1488 | * for NMI context. Thise allows for lockless recording. | |
1489 | * | |
1490 | * Note, if the buffers failed to be allocated, then this returns NULL | |
1491 | */ | |
1492 | static char *get_trace_buf(void) | |
1493 | { | |
1494 | struct trace_buffer_struct *percpu_buffer; | |
1495 | struct trace_buffer_struct *buffer; | |
1496 | ||
1497 | /* | |
1498 | * If we have allocated per cpu buffers, then we do not | |
1499 | * need to do any locking. | |
1500 | */ | |
1501 | if (in_nmi()) | |
1502 | percpu_buffer = trace_percpu_nmi_buffer; | |
1503 | else if (in_irq()) | |
1504 | percpu_buffer = trace_percpu_irq_buffer; | |
1505 | else if (in_softirq()) | |
1506 | percpu_buffer = trace_percpu_sirq_buffer; | |
1507 | else | |
1508 | percpu_buffer = trace_percpu_buffer; | |
1509 | ||
1510 | if (!percpu_buffer) | |
1511 | return NULL; | |
1512 | ||
1513 | buffer = per_cpu_ptr(percpu_buffer, smp_processor_id()); | |
1514 | ||
1515 | return buffer->buffer; | |
1516 | } | |
1517 | ||
1518 | static int alloc_percpu_trace_buffer(void) | |
1519 | { | |
1520 | struct trace_buffer_struct *buffers; | |
1521 | struct trace_buffer_struct *sirq_buffers; | |
1522 | struct trace_buffer_struct *irq_buffers; | |
1523 | struct trace_buffer_struct *nmi_buffers; | |
1524 | ||
1525 | buffers = alloc_percpu(struct trace_buffer_struct); | |
1526 | if (!buffers) | |
1527 | goto err_warn; | |
1528 | ||
1529 | sirq_buffers = alloc_percpu(struct trace_buffer_struct); | |
1530 | if (!sirq_buffers) | |
1531 | goto err_sirq; | |
1532 | ||
1533 | irq_buffers = alloc_percpu(struct trace_buffer_struct); | |
1534 | if (!irq_buffers) | |
1535 | goto err_irq; | |
1536 | ||
1537 | nmi_buffers = alloc_percpu(struct trace_buffer_struct); | |
1538 | if (!nmi_buffers) | |
1539 | goto err_nmi; | |
1540 | ||
1541 | trace_percpu_buffer = buffers; | |
1542 | trace_percpu_sirq_buffer = sirq_buffers; | |
1543 | trace_percpu_irq_buffer = irq_buffers; | |
1544 | trace_percpu_nmi_buffer = nmi_buffers; | |
1545 | ||
1546 | return 0; | |
1547 | ||
1548 | err_nmi: | |
1549 | free_percpu(irq_buffers); | |
1550 | err_irq: | |
1551 | free_percpu(sirq_buffers); | |
1552 | err_sirq: | |
1553 | free_percpu(buffers); | |
1554 | err_warn: | |
1555 | WARN(1, "Could not allocate percpu trace_printk buffer"); | |
1556 | return -ENOMEM; | |
1557 | } | |
1558 | ||
1559 | void trace_printk_init_buffers(void) | |
1560 | { | |
1561 | static int buffers_allocated; | |
1562 | ||
1563 | if (buffers_allocated) | |
1564 | return; | |
1565 | ||
1566 | if (alloc_percpu_trace_buffer()) | |
1567 | return; | |
1568 | ||
1569 | pr_info("ftrace: Allocated trace_printk buffers\n"); | |
1570 | ||
1571 | buffers_allocated = 1; | |
1572 | } | |
1573 | ||
769b0441 | 1574 | /** |
48ead020 | 1575 | * trace_vbprintk - write binary msg to tracing buffer |
769b0441 FW |
1576 | * |
1577 | */ | |
40ce74f1 | 1578 | int trace_vbprintk(unsigned long ip, const char *fmt, va_list args) |
769b0441 | 1579 | { |
e1112b4d | 1580 | struct ftrace_event_call *call = &event_bprint; |
769b0441 | 1581 | struct ring_buffer_event *event; |
e77405ad | 1582 | struct ring_buffer *buffer; |
769b0441 | 1583 | struct trace_array *tr = &global_trace; |
48ead020 | 1584 | struct bprint_entry *entry; |
769b0441 | 1585 | unsigned long flags; |
07d777fe SR |
1586 | char *tbuffer; |
1587 | int len = 0, size, pc; | |
769b0441 FW |
1588 | |
1589 | if (unlikely(tracing_selftest_running || tracing_disabled)) | |
1590 | return 0; | |
1591 | ||
1592 | /* Don't pollute graph traces with trace_vprintk internals */ | |
1593 | pause_graph_tracing(); | |
1594 | ||
1595 | pc = preempt_count(); | |
5168ae50 | 1596 | preempt_disable_notrace(); |
769b0441 | 1597 | |
07d777fe SR |
1598 | tbuffer = get_trace_buf(); |
1599 | if (!tbuffer) { | |
1600 | len = 0; | |
769b0441 | 1601 | goto out; |
07d777fe | 1602 | } |
769b0441 | 1603 | |
07d777fe | 1604 | len = vbin_printf((u32 *)tbuffer, TRACE_BUF_SIZE/sizeof(int), fmt, args); |
769b0441 | 1605 | |
07d777fe SR |
1606 | if (len > TRACE_BUF_SIZE/sizeof(int) || len < 0) |
1607 | goto out; | |
769b0441 | 1608 | |
07d777fe | 1609 | local_save_flags(flags); |
769b0441 | 1610 | size = sizeof(*entry) + sizeof(u32) * len; |
e77405ad SR |
1611 | buffer = tr->buffer; |
1612 | event = trace_buffer_lock_reserve(buffer, TRACE_BPRINT, size, | |
1613 | flags, pc); | |
769b0441 | 1614 | if (!event) |
07d777fe | 1615 | goto out; |
769b0441 FW |
1616 | entry = ring_buffer_event_data(event); |
1617 | entry->ip = ip; | |
769b0441 FW |
1618 | entry->fmt = fmt; |
1619 | ||
07d777fe | 1620 | memcpy(entry->buf, tbuffer, sizeof(u32) * len); |
d931369b | 1621 | if (!filter_check_discard(call, entry, buffer, event)) { |
e77405ad | 1622 | ring_buffer_unlock_commit(buffer, event); |
d931369b SR |
1623 | ftrace_trace_stack(buffer, flags, 6, pc); |
1624 | } | |
769b0441 | 1625 | |
769b0441 | 1626 | out: |
5168ae50 | 1627 | preempt_enable_notrace(); |
769b0441 FW |
1628 | unpause_graph_tracing(); |
1629 | ||
1630 | return len; | |
1631 | } | |
48ead020 FW |
1632 | EXPORT_SYMBOL_GPL(trace_vbprintk); |
1633 | ||
659372d3 SR |
1634 | int trace_array_printk(struct trace_array *tr, |
1635 | unsigned long ip, const char *fmt, ...) | |
1636 | { | |
1637 | int ret; | |
1638 | va_list ap; | |
1639 | ||
1640 | if (!(trace_flags & TRACE_ITER_PRINTK)) | |
1641 | return 0; | |
1642 | ||
1643 | va_start(ap, fmt); | |
1644 | ret = trace_array_vprintk(tr, ip, fmt, ap); | |
1645 | va_end(ap); | |
1646 | return ret; | |
1647 | } | |
1648 | ||
1649 | int trace_array_vprintk(struct trace_array *tr, | |
1650 | unsigned long ip, const char *fmt, va_list args) | |
48ead020 | 1651 | { |
e1112b4d | 1652 | struct ftrace_event_call *call = &event_print; |
48ead020 | 1653 | struct ring_buffer_event *event; |
e77405ad | 1654 | struct ring_buffer *buffer; |
07d777fe | 1655 | int len = 0, size, pc; |
48ead020 | 1656 | struct print_entry *entry; |
07d777fe SR |
1657 | unsigned long flags; |
1658 | char *tbuffer; | |
48ead020 FW |
1659 | |
1660 | if (tracing_disabled || tracing_selftest_running) | |
1661 | return 0; | |
1662 | ||
07d777fe SR |
1663 | /* Don't pollute graph traces with trace_vprintk internals */ |
1664 | pause_graph_tracing(); | |
1665 | ||
48ead020 FW |
1666 | pc = preempt_count(); |
1667 | preempt_disable_notrace(); | |
48ead020 | 1668 | |
07d777fe SR |
1669 | |
1670 | tbuffer = get_trace_buf(); | |
1671 | if (!tbuffer) { | |
1672 | len = 0; | |
48ead020 | 1673 | goto out; |
07d777fe | 1674 | } |
48ead020 | 1675 | |
07d777fe SR |
1676 | len = vsnprintf(tbuffer, TRACE_BUF_SIZE, fmt, args); |
1677 | if (len > TRACE_BUF_SIZE) | |
1678 | goto out; | |
48ead020 | 1679 | |
07d777fe | 1680 | local_save_flags(flags); |
48ead020 | 1681 | size = sizeof(*entry) + len + 1; |
e77405ad SR |
1682 | buffer = tr->buffer; |
1683 | event = trace_buffer_lock_reserve(buffer, TRACE_PRINT, size, | |
07d777fe | 1684 | flags, pc); |
48ead020 | 1685 | if (!event) |
07d777fe | 1686 | goto out; |
48ead020 | 1687 | entry = ring_buffer_event_data(event); |
c13d2f7c | 1688 | entry->ip = ip; |
48ead020 | 1689 | |
07d777fe | 1690 | memcpy(&entry->buf, tbuffer, len); |
c13d2f7c | 1691 | entry->buf[len] = '\0'; |
d931369b | 1692 | if (!filter_check_discard(call, entry, buffer, event)) { |
e77405ad | 1693 | ring_buffer_unlock_commit(buffer, event); |
07d777fe | 1694 | ftrace_trace_stack(buffer, flags, 6, pc); |
d931369b | 1695 | } |
48ead020 FW |
1696 | out: |
1697 | preempt_enable_notrace(); | |
07d777fe | 1698 | unpause_graph_tracing(); |
48ead020 FW |
1699 | |
1700 | return len; | |
1701 | } | |
659372d3 SR |
1702 | |
1703 | int trace_vprintk(unsigned long ip, const char *fmt, va_list args) | |
1704 | { | |
a813a159 | 1705 | return trace_array_vprintk(&global_trace, ip, fmt, args); |
659372d3 | 1706 | } |
769b0441 FW |
1707 | EXPORT_SYMBOL_GPL(trace_vprintk); |
1708 | ||
e2ac8ef5 | 1709 | static void trace_iterator_increment(struct trace_iterator *iter) |
5a90f577 SR |
1710 | { |
1711 | iter->idx++; | |
d769041f SR |
1712 | if (iter->buffer_iter[iter->cpu]) |
1713 | ring_buffer_read(iter->buffer_iter[iter->cpu], NULL); | |
5a90f577 SR |
1714 | } |
1715 | ||
e309b41d | 1716 | static struct trace_entry * |
bc21b478 SR |
1717 | peek_next_entry(struct trace_iterator *iter, int cpu, u64 *ts, |
1718 | unsigned long *lost_events) | |
dd0e545f | 1719 | { |
3928a8a2 SR |
1720 | struct ring_buffer_event *event; |
1721 | struct ring_buffer_iter *buf_iter = iter->buffer_iter[cpu]; | |
dd0e545f | 1722 | |
d769041f SR |
1723 | if (buf_iter) |
1724 | event = ring_buffer_iter_peek(buf_iter, ts); | |
1725 | else | |
bc21b478 SR |
1726 | event = ring_buffer_peek(iter->tr->buffer, cpu, ts, |
1727 | lost_events); | |
d769041f | 1728 | |
4a9bd3f1 SR |
1729 | if (event) { |
1730 | iter->ent_size = ring_buffer_event_length(event); | |
1731 | return ring_buffer_event_data(event); | |
1732 | } | |
1733 | iter->ent_size = 0; | |
1734 | return NULL; | |
dd0e545f | 1735 | } |
d769041f | 1736 | |
dd0e545f | 1737 | static struct trace_entry * |
bc21b478 SR |
1738 | __find_next_entry(struct trace_iterator *iter, int *ent_cpu, |
1739 | unsigned long *missing_events, u64 *ent_ts) | |
bc0c38d1 | 1740 | { |
3928a8a2 | 1741 | struct ring_buffer *buffer = iter->tr->buffer; |
bc0c38d1 | 1742 | struct trace_entry *ent, *next = NULL; |
aa27497c | 1743 | unsigned long lost_events = 0, next_lost = 0; |
b04cc6b1 | 1744 | int cpu_file = iter->cpu_file; |
3928a8a2 | 1745 | u64 next_ts = 0, ts; |
bc0c38d1 | 1746 | int next_cpu = -1; |
12b5da34 | 1747 | int next_size = 0; |
bc0c38d1 SR |
1748 | int cpu; |
1749 | ||
b04cc6b1 FW |
1750 | /* |
1751 | * If we are in a per_cpu trace file, don't bother by iterating over | |
1752 | * all cpu and peek directly. | |
1753 | */ | |
1754 | if (cpu_file > TRACE_PIPE_ALL_CPU) { | |
1755 | if (ring_buffer_empty_cpu(buffer, cpu_file)) | |
1756 | return NULL; | |
bc21b478 | 1757 | ent = peek_next_entry(iter, cpu_file, ent_ts, missing_events); |
b04cc6b1 FW |
1758 | if (ent_cpu) |
1759 | *ent_cpu = cpu_file; | |
1760 | ||
1761 | return ent; | |
1762 | } | |
1763 | ||
ab46428c | 1764 | for_each_tracing_cpu(cpu) { |
dd0e545f | 1765 | |
3928a8a2 SR |
1766 | if (ring_buffer_empty_cpu(buffer, cpu)) |
1767 | continue; | |
dd0e545f | 1768 | |
bc21b478 | 1769 | ent = peek_next_entry(iter, cpu, &ts, &lost_events); |
dd0e545f | 1770 | |
cdd31cd2 IM |
1771 | /* |
1772 | * Pick the entry with the smallest timestamp: | |
1773 | */ | |
3928a8a2 | 1774 | if (ent && (!next || ts < next_ts)) { |
bc0c38d1 SR |
1775 | next = ent; |
1776 | next_cpu = cpu; | |
3928a8a2 | 1777 | next_ts = ts; |
bc21b478 | 1778 | next_lost = lost_events; |
12b5da34 | 1779 | next_size = iter->ent_size; |
bc0c38d1 SR |
1780 | } |
1781 | } | |
1782 | ||
12b5da34 SR |
1783 | iter->ent_size = next_size; |
1784 | ||
bc0c38d1 SR |
1785 | if (ent_cpu) |
1786 | *ent_cpu = next_cpu; | |
1787 | ||
3928a8a2 SR |
1788 | if (ent_ts) |
1789 | *ent_ts = next_ts; | |
1790 | ||
bc21b478 SR |
1791 | if (missing_events) |
1792 | *missing_events = next_lost; | |
1793 | ||
bc0c38d1 SR |
1794 | return next; |
1795 | } | |
1796 | ||
dd0e545f | 1797 | /* Find the next real entry, without updating the iterator itself */ |
c4a8e8be FW |
1798 | struct trace_entry *trace_find_next_entry(struct trace_iterator *iter, |
1799 | int *ent_cpu, u64 *ent_ts) | |
bc0c38d1 | 1800 | { |
bc21b478 | 1801 | return __find_next_entry(iter, ent_cpu, NULL, ent_ts); |
dd0e545f SR |
1802 | } |
1803 | ||
1804 | /* Find the next real entry, and increment the iterator to the next entry */ | |
955b61e5 | 1805 | void *trace_find_next_entry_inc(struct trace_iterator *iter) |
dd0e545f | 1806 | { |
bc21b478 SR |
1807 | iter->ent = __find_next_entry(iter, &iter->cpu, |
1808 | &iter->lost_events, &iter->ts); | |
dd0e545f | 1809 | |
3928a8a2 | 1810 | if (iter->ent) |
e2ac8ef5 | 1811 | trace_iterator_increment(iter); |
dd0e545f | 1812 | |
3928a8a2 | 1813 | return iter->ent ? iter : NULL; |
b3806b43 | 1814 | } |
bc0c38d1 | 1815 | |
e309b41d | 1816 | static void trace_consume(struct trace_iterator *iter) |
b3806b43 | 1817 | { |
bc21b478 SR |
1818 | ring_buffer_consume(iter->tr->buffer, iter->cpu, &iter->ts, |
1819 | &iter->lost_events); | |
bc0c38d1 SR |
1820 | } |
1821 | ||
e309b41d | 1822 | static void *s_next(struct seq_file *m, void *v, loff_t *pos) |
bc0c38d1 SR |
1823 | { |
1824 | struct trace_iterator *iter = m->private; | |
bc0c38d1 | 1825 | int i = (int)*pos; |
4e3c3333 | 1826 | void *ent; |
bc0c38d1 | 1827 | |
a63ce5b3 SR |
1828 | WARN_ON_ONCE(iter->leftover); |
1829 | ||
bc0c38d1 SR |
1830 | (*pos)++; |
1831 | ||
1832 | /* can't go backwards */ | |
1833 | if (iter->idx > i) | |
1834 | return NULL; | |
1835 | ||
1836 | if (iter->idx < 0) | |
955b61e5 | 1837 | ent = trace_find_next_entry_inc(iter); |
bc0c38d1 SR |
1838 | else |
1839 | ent = iter; | |
1840 | ||
1841 | while (ent && iter->idx < i) | |
955b61e5 | 1842 | ent = trace_find_next_entry_inc(iter); |
bc0c38d1 SR |
1843 | |
1844 | iter->pos = *pos; | |
1845 | ||
bc0c38d1 SR |
1846 | return ent; |
1847 | } | |
1848 | ||
955b61e5 | 1849 | void tracing_iter_reset(struct trace_iterator *iter, int cpu) |
2f26ebd5 SR |
1850 | { |
1851 | struct trace_array *tr = iter->tr; | |
1852 | struct ring_buffer_event *event; | |
1853 | struct ring_buffer_iter *buf_iter; | |
1854 | unsigned long entries = 0; | |
1855 | u64 ts; | |
1856 | ||
1857 | tr->data[cpu]->skipped_entries = 0; | |
1858 | ||
1859 | if (!iter->buffer_iter[cpu]) | |
1860 | return; | |
1861 | ||
1862 | buf_iter = iter->buffer_iter[cpu]; | |
1863 | ring_buffer_iter_reset(buf_iter); | |
1864 | ||
1865 | /* | |
1866 | * We could have the case with the max latency tracers | |
1867 | * that a reset never took place on a cpu. This is evident | |
1868 | * by the timestamp being before the start of the buffer. | |
1869 | */ | |
1870 | while ((event = ring_buffer_iter_peek(buf_iter, &ts))) { | |
1871 | if (ts >= iter->tr->time_start) | |
1872 | break; | |
1873 | entries++; | |
1874 | ring_buffer_read(buf_iter, NULL); | |
1875 | } | |
1876 | ||
1877 | tr->data[cpu]->skipped_entries = entries; | |
1878 | } | |
1879 | ||
d7350c3f | 1880 | /* |
d7350c3f FW |
1881 | * The current tracer is copied to avoid a global locking |
1882 | * all around. | |
1883 | */ | |
bc0c38d1 SR |
1884 | static void *s_start(struct seq_file *m, loff_t *pos) |
1885 | { | |
1886 | struct trace_iterator *iter = m->private; | |
d7350c3f | 1887 | static struct tracer *old_tracer; |
b04cc6b1 | 1888 | int cpu_file = iter->cpu_file; |
bc0c38d1 SR |
1889 | void *p = NULL; |
1890 | loff_t l = 0; | |
3928a8a2 | 1891 | int cpu; |
bc0c38d1 | 1892 | |
d7350c3f | 1893 | /* copy the tracer to avoid using a global lock all around */ |
bc0c38d1 | 1894 | mutex_lock(&trace_types_lock); |
d7350c3f FW |
1895 | if (unlikely(old_tracer != current_trace && current_trace)) { |
1896 | old_tracer = current_trace; | |
1897 | *iter->trace = *current_trace; | |
d15f57f2 | 1898 | } |
d7350c3f | 1899 | mutex_unlock(&trace_types_lock); |
bc0c38d1 SR |
1900 | |
1901 | atomic_inc(&trace_record_cmdline_disabled); | |
1902 | ||
bc0c38d1 SR |
1903 | if (*pos != iter->pos) { |
1904 | iter->ent = NULL; | |
1905 | iter->cpu = 0; | |
1906 | iter->idx = -1; | |
1907 | ||
b04cc6b1 FW |
1908 | if (cpu_file == TRACE_PIPE_ALL_CPU) { |
1909 | for_each_tracing_cpu(cpu) | |
2f26ebd5 | 1910 | tracing_iter_reset(iter, cpu); |
b04cc6b1 | 1911 | } else |
2f26ebd5 | 1912 | tracing_iter_reset(iter, cpu_file); |
bc0c38d1 | 1913 | |
ac91d854 | 1914 | iter->leftover = 0; |
bc0c38d1 SR |
1915 | for (p = iter; p && l < *pos; p = s_next(m, p, &l)) |
1916 | ; | |
1917 | ||
1918 | } else { | |
a63ce5b3 SR |
1919 | /* |
1920 | * If we overflowed the seq_file before, then we want | |
1921 | * to just reuse the trace_seq buffer again. | |
1922 | */ | |
1923 | if (iter->leftover) | |
1924 | p = iter; | |
1925 | else { | |
1926 | l = *pos - 1; | |
1927 | p = s_next(m, p, &l); | |
1928 | } | |
bc0c38d1 SR |
1929 | } |
1930 | ||
4f535968 | 1931 | trace_event_read_lock(); |
7e53bd42 | 1932 | trace_access_lock(cpu_file); |
bc0c38d1 SR |
1933 | return p; |
1934 | } | |
1935 | ||
1936 | static void s_stop(struct seq_file *m, void *p) | |
1937 | { | |
7e53bd42 LJ |
1938 | struct trace_iterator *iter = m->private; |
1939 | ||
bc0c38d1 | 1940 | atomic_dec(&trace_record_cmdline_disabled); |
7e53bd42 | 1941 | trace_access_unlock(iter->cpu_file); |
4f535968 | 1942 | trace_event_read_unlock(); |
bc0c38d1 SR |
1943 | } |
1944 | ||
39eaf7ef SR |
1945 | static void |
1946 | get_total_entries(struct trace_array *tr, unsigned long *total, unsigned long *entries) | |
1947 | { | |
1948 | unsigned long count; | |
1949 | int cpu; | |
1950 | ||
1951 | *total = 0; | |
1952 | *entries = 0; | |
1953 | ||
1954 | for_each_tracing_cpu(cpu) { | |
1955 | count = ring_buffer_entries_cpu(tr->buffer, cpu); | |
1956 | /* | |
1957 | * If this buffer has skipped entries, then we hold all | |
1958 | * entries for the trace and we need to ignore the | |
1959 | * ones before the time stamp. | |
1960 | */ | |
1961 | if (tr->data[cpu]->skipped_entries) { | |
1962 | count -= tr->data[cpu]->skipped_entries; | |
1963 | /* total is the same as the entries */ | |
1964 | *total += count; | |
1965 | } else | |
1966 | *total += count + | |
1967 | ring_buffer_overrun_cpu(tr->buffer, cpu); | |
1968 | *entries += count; | |
1969 | } | |
1970 | } | |
1971 | ||
e309b41d | 1972 | static void print_lat_help_header(struct seq_file *m) |
bc0c38d1 | 1973 | { |
a6168353 ME |
1974 | seq_puts(m, "# _------=> CPU# \n"); |
1975 | seq_puts(m, "# / _-----=> irqs-off \n"); | |
1976 | seq_puts(m, "# | / _----=> need-resched \n"); | |
1977 | seq_puts(m, "# || / _---=> hardirq/softirq \n"); | |
1978 | seq_puts(m, "# ||| / _--=> preempt-depth \n"); | |
e6e1e259 SR |
1979 | seq_puts(m, "# |||| / delay \n"); |
1980 | seq_puts(m, "# cmd pid ||||| time | caller \n"); | |
1981 | seq_puts(m, "# \\ / ||||| \\ | / \n"); | |
bc0c38d1 SR |
1982 | } |
1983 | ||
39eaf7ef | 1984 | static void print_event_info(struct trace_array *tr, struct seq_file *m) |
bc0c38d1 | 1985 | { |
39eaf7ef SR |
1986 | unsigned long total; |
1987 | unsigned long entries; | |
1988 | ||
1989 | get_total_entries(tr, &total, &entries); | |
1990 | seq_printf(m, "# entries-in-buffer/entries-written: %lu/%lu #P:%d\n", | |
1991 | entries, total, num_online_cpus()); | |
1992 | seq_puts(m, "#\n"); | |
1993 | } | |
1994 | ||
1995 | static void print_func_help_header(struct trace_array *tr, struct seq_file *m) | |
1996 | { | |
1997 | print_event_info(tr, m); | |
77271ce4 | 1998 | seq_puts(m, "# TASK-PID CPU# TIMESTAMP FUNCTION\n"); |
a6168353 | 1999 | seq_puts(m, "# | | | | |\n"); |
bc0c38d1 SR |
2000 | } |
2001 | ||
39eaf7ef | 2002 | static void print_func_help_header_irq(struct trace_array *tr, struct seq_file *m) |
77271ce4 | 2003 | { |
39eaf7ef | 2004 | print_event_info(tr, m); |
77271ce4 SR |
2005 | seq_puts(m, "# _-----=> irqs-off\n"); |
2006 | seq_puts(m, "# / _----=> need-resched\n"); | |
2007 | seq_puts(m, "# | / _---=> hardirq/softirq\n"); | |
2008 | seq_puts(m, "# || / _--=> preempt-depth\n"); | |
2009 | seq_puts(m, "# ||| / delay\n"); | |
2010 | seq_puts(m, "# TASK-PID CPU# |||| TIMESTAMP FUNCTION\n"); | |
2011 | seq_puts(m, "# | | | |||| | |\n"); | |
2012 | } | |
bc0c38d1 | 2013 | |
62b915f1 | 2014 | void |
bc0c38d1 SR |
2015 | print_trace_header(struct seq_file *m, struct trace_iterator *iter) |
2016 | { | |
2017 | unsigned long sym_flags = (trace_flags & TRACE_ITER_SYM_MASK); | |
2018 | struct trace_array *tr = iter->tr; | |
2019 | struct trace_array_cpu *data = tr->data[tr->cpu]; | |
2020 | struct tracer *type = current_trace; | |
39eaf7ef SR |
2021 | unsigned long entries; |
2022 | unsigned long total; | |
bc0c38d1 SR |
2023 | const char *name = "preemption"; |
2024 | ||
2025 | if (type) | |
2026 | name = type->name; | |
2027 | ||
39eaf7ef | 2028 | get_total_entries(tr, &total, &entries); |
bc0c38d1 | 2029 | |
888b55dc | 2030 | seq_printf(m, "# %s latency trace v1.1.5 on %s\n", |
bc0c38d1 | 2031 | name, UTS_RELEASE); |
888b55dc | 2032 | seq_puts(m, "# -----------------------------------" |
bc0c38d1 | 2033 | "---------------------------------\n"); |
888b55dc | 2034 | seq_printf(m, "# latency: %lu us, #%lu/%lu, CPU#%d |" |
bc0c38d1 | 2035 | " (M:%s VP:%d, KP:%d, SP:%d HP:%d", |
57f50be1 | 2036 | nsecs_to_usecs(data->saved_latency), |
bc0c38d1 | 2037 | entries, |
4c11d7ae | 2038 | total, |
bc0c38d1 SR |
2039 | tr->cpu, |
2040 | #if defined(CONFIG_PREEMPT_NONE) | |
2041 | "server", | |
2042 | #elif defined(CONFIG_PREEMPT_VOLUNTARY) | |
2043 | "desktop", | |
b5c21b45 | 2044 | #elif defined(CONFIG_PREEMPT) |
bc0c38d1 SR |
2045 | "preempt", |
2046 | #else | |
2047 | "unknown", | |
2048 | #endif | |
2049 | /* These are reserved for later use */ | |
2050 | 0, 0, 0, 0); | |
2051 | #ifdef CONFIG_SMP | |
2052 | seq_printf(m, " #P:%d)\n", num_online_cpus()); | |
2053 | #else | |
2054 | seq_puts(m, ")\n"); | |
2055 | #endif | |
888b55dc KM |
2056 | seq_puts(m, "# -----------------\n"); |
2057 | seq_printf(m, "# | task: %.16s-%d " | |
bc0c38d1 SR |
2058 | "(uid:%d nice:%ld policy:%ld rt_prio:%ld)\n", |
2059 | data->comm, data->pid, data->uid, data->nice, | |
2060 | data->policy, data->rt_priority); | |
888b55dc | 2061 | seq_puts(m, "# -----------------\n"); |
bc0c38d1 SR |
2062 | |
2063 | if (data->critical_start) { | |
888b55dc | 2064 | seq_puts(m, "# => started at: "); |
214023c3 SR |
2065 | seq_print_ip_sym(&iter->seq, data->critical_start, sym_flags); |
2066 | trace_print_seq(m, &iter->seq); | |
888b55dc | 2067 | seq_puts(m, "\n# => ended at: "); |
214023c3 SR |
2068 | seq_print_ip_sym(&iter->seq, data->critical_end, sym_flags); |
2069 | trace_print_seq(m, &iter->seq); | |
8248ac05 | 2070 | seq_puts(m, "\n#\n"); |
bc0c38d1 SR |
2071 | } |
2072 | ||
888b55dc | 2073 | seq_puts(m, "#\n"); |
bc0c38d1 SR |
2074 | } |
2075 | ||
a309720c SR |
2076 | static void test_cpu_buff_start(struct trace_iterator *iter) |
2077 | { | |
2078 | struct trace_seq *s = &iter->seq; | |
2079 | ||
12ef7d44 SR |
2080 | if (!(trace_flags & TRACE_ITER_ANNOTATE)) |
2081 | return; | |
2082 | ||
2083 | if (!(iter->iter_flags & TRACE_FILE_ANNOTATE)) | |
2084 | return; | |
2085 | ||
4462344e | 2086 | if (cpumask_test_cpu(iter->cpu, iter->started)) |
a309720c SR |
2087 | return; |
2088 | ||
2f26ebd5 SR |
2089 | if (iter->tr->data[iter->cpu]->skipped_entries) |
2090 | return; | |
2091 | ||
4462344e | 2092 | cpumask_set_cpu(iter->cpu, iter->started); |
b0dfa978 FW |
2093 | |
2094 | /* Don't print started cpu buffer for the first entry of the trace */ | |
2095 | if (iter->idx > 1) | |
2096 | trace_seq_printf(s, "##### CPU %u buffer started ####\n", | |
2097 | iter->cpu); | |
a309720c SR |
2098 | } |
2099 | ||
2c4f035f | 2100 | static enum print_line_t print_trace_fmt(struct trace_iterator *iter) |
bc0c38d1 | 2101 | { |
214023c3 | 2102 | struct trace_seq *s = &iter->seq; |
bc0c38d1 | 2103 | unsigned long sym_flags = (trace_flags & TRACE_ITER_SYM_MASK); |
4e3c3333 | 2104 | struct trace_entry *entry; |
f633cef0 | 2105 | struct trace_event *event; |
bc0c38d1 | 2106 | |
4e3c3333 | 2107 | entry = iter->ent; |
dd0e545f | 2108 | |
a309720c SR |
2109 | test_cpu_buff_start(iter); |
2110 | ||
c4a8e8be | 2111 | event = ftrace_find_event(entry->type); |
bc0c38d1 | 2112 | |
c4a8e8be | 2113 | if (trace_flags & TRACE_ITER_CONTEXT_INFO) { |
27d48be8 SR |
2114 | if (iter->iter_flags & TRACE_FILE_LAT_FMT) { |
2115 | if (!trace_print_lat_context(iter)) | |
2116 | goto partial; | |
2117 | } else { | |
2118 | if (!trace_print_context(iter)) | |
2119 | goto partial; | |
2120 | } | |
c4a8e8be | 2121 | } |
bc0c38d1 | 2122 | |
268ccda0 | 2123 | if (event) |
a9a57763 | 2124 | return event->funcs->trace(iter, sym_flags, event); |
d9793bd8 ACM |
2125 | |
2126 | if (!trace_seq_printf(s, "Unknown type %d\n", entry->type)) | |
2127 | goto partial; | |
02b67518 | 2128 | |
2c4f035f | 2129 | return TRACE_TYPE_HANDLED; |
d9793bd8 ACM |
2130 | partial: |
2131 | return TRACE_TYPE_PARTIAL_LINE; | |
bc0c38d1 SR |
2132 | } |
2133 | ||
2c4f035f | 2134 | static enum print_line_t print_raw_fmt(struct trace_iterator *iter) |
f9896bf3 IM |
2135 | { |
2136 | struct trace_seq *s = &iter->seq; | |
2137 | struct trace_entry *entry; | |
f633cef0 | 2138 | struct trace_event *event; |
f9896bf3 IM |
2139 | |
2140 | entry = iter->ent; | |
dd0e545f | 2141 | |
c4a8e8be | 2142 | if (trace_flags & TRACE_ITER_CONTEXT_INFO) { |
d9793bd8 ACM |
2143 | if (!trace_seq_printf(s, "%d %d %llu ", |
2144 | entry->pid, iter->cpu, iter->ts)) | |
2145 | goto partial; | |
c4a8e8be | 2146 | } |
f9896bf3 | 2147 | |
f633cef0 | 2148 | event = ftrace_find_event(entry->type); |
268ccda0 | 2149 | if (event) |
a9a57763 | 2150 | return event->funcs->raw(iter, 0, event); |
d9793bd8 ACM |
2151 | |
2152 | if (!trace_seq_printf(s, "%d ?\n", entry->type)) | |
2153 | goto partial; | |
777e208d | 2154 | |
2c4f035f | 2155 | return TRACE_TYPE_HANDLED; |
d9793bd8 ACM |
2156 | partial: |
2157 | return TRACE_TYPE_PARTIAL_LINE; | |
f9896bf3 IM |
2158 | } |
2159 | ||
2c4f035f | 2160 | static enum print_line_t print_hex_fmt(struct trace_iterator *iter) |
5e3ca0ec IM |
2161 | { |
2162 | struct trace_seq *s = &iter->seq; | |
2163 | unsigned char newline = '\n'; | |
2164 | struct trace_entry *entry; | |
f633cef0 | 2165 | struct trace_event *event; |
5e3ca0ec IM |
2166 | |
2167 | entry = iter->ent; | |
dd0e545f | 2168 | |
c4a8e8be FW |
2169 | if (trace_flags & TRACE_ITER_CONTEXT_INFO) { |
2170 | SEQ_PUT_HEX_FIELD_RET(s, entry->pid); | |
2171 | SEQ_PUT_HEX_FIELD_RET(s, iter->cpu); | |
2172 | SEQ_PUT_HEX_FIELD_RET(s, iter->ts); | |
2173 | } | |
5e3ca0ec | 2174 | |
f633cef0 | 2175 | event = ftrace_find_event(entry->type); |
268ccda0 | 2176 | if (event) { |
a9a57763 | 2177 | enum print_line_t ret = event->funcs->hex(iter, 0, event); |
d9793bd8 ACM |
2178 | if (ret != TRACE_TYPE_HANDLED) |
2179 | return ret; | |
2180 | } | |
7104f300 | 2181 | |
5e3ca0ec IM |
2182 | SEQ_PUT_FIELD_RET(s, newline); |
2183 | ||
2c4f035f | 2184 | return TRACE_TYPE_HANDLED; |
5e3ca0ec IM |
2185 | } |
2186 | ||
2c4f035f | 2187 | static enum print_line_t print_bin_fmt(struct trace_iterator *iter) |
cb0f12aa IM |
2188 | { |
2189 | struct trace_seq *s = &iter->seq; | |
2190 | struct trace_entry *entry; | |
f633cef0 | 2191 | struct trace_event *event; |
cb0f12aa IM |
2192 | |
2193 | entry = iter->ent; | |
dd0e545f | 2194 | |
c4a8e8be FW |
2195 | if (trace_flags & TRACE_ITER_CONTEXT_INFO) { |
2196 | SEQ_PUT_FIELD_RET(s, entry->pid); | |
1830b52d | 2197 | SEQ_PUT_FIELD_RET(s, iter->cpu); |
c4a8e8be FW |
2198 | SEQ_PUT_FIELD_RET(s, iter->ts); |
2199 | } | |
cb0f12aa | 2200 | |
f633cef0 | 2201 | event = ftrace_find_event(entry->type); |
a9a57763 SR |
2202 | return event ? event->funcs->binary(iter, 0, event) : |
2203 | TRACE_TYPE_HANDLED; | |
cb0f12aa IM |
2204 | } |
2205 | ||
62b915f1 | 2206 | int trace_empty(struct trace_iterator *iter) |
bc0c38d1 | 2207 | { |
bc0c38d1 SR |
2208 | int cpu; |
2209 | ||
9aba60fe SR |
2210 | /* If we are looking at one CPU buffer, only check that one */ |
2211 | if (iter->cpu_file != TRACE_PIPE_ALL_CPU) { | |
2212 | cpu = iter->cpu_file; | |
2213 | if (iter->buffer_iter[cpu]) { | |
2214 | if (!ring_buffer_iter_empty(iter->buffer_iter[cpu])) | |
2215 | return 0; | |
2216 | } else { | |
2217 | if (!ring_buffer_empty_cpu(iter->tr->buffer, cpu)) | |
2218 | return 0; | |
2219 | } | |
2220 | return 1; | |
2221 | } | |
2222 | ||
ab46428c | 2223 | for_each_tracing_cpu(cpu) { |
d769041f SR |
2224 | if (iter->buffer_iter[cpu]) { |
2225 | if (!ring_buffer_iter_empty(iter->buffer_iter[cpu])) | |
2226 | return 0; | |
2227 | } else { | |
2228 | if (!ring_buffer_empty_cpu(iter->tr->buffer, cpu)) | |
2229 | return 0; | |
2230 | } | |
bc0c38d1 | 2231 | } |
d769041f | 2232 | |
797d3712 | 2233 | return 1; |
bc0c38d1 SR |
2234 | } |
2235 | ||
4f535968 | 2236 | /* Called with trace_event_read_lock() held. */ |
955b61e5 | 2237 | enum print_line_t print_trace_line(struct trace_iterator *iter) |
f9896bf3 | 2238 | { |
2c4f035f FW |
2239 | enum print_line_t ret; |
2240 | ||
ee5e51f5 JO |
2241 | if (iter->lost_events && |
2242 | !trace_seq_printf(&iter->seq, "CPU:%d [LOST %lu EVENTS]\n", | |
2243 | iter->cpu, iter->lost_events)) | |
2244 | return TRACE_TYPE_PARTIAL_LINE; | |
bc21b478 | 2245 | |
2c4f035f FW |
2246 | if (iter->trace && iter->trace->print_line) { |
2247 | ret = iter->trace->print_line(iter); | |
2248 | if (ret != TRACE_TYPE_UNHANDLED) | |
2249 | return ret; | |
2250 | } | |
72829bc3 | 2251 | |
48ead020 FW |
2252 | if (iter->ent->type == TRACE_BPRINT && |
2253 | trace_flags & TRACE_ITER_PRINTK && | |
2254 | trace_flags & TRACE_ITER_PRINTK_MSGONLY) | |
5ef841f6 | 2255 | return trace_print_bprintk_msg_only(iter); |
48ead020 | 2256 | |
66896a85 FW |
2257 | if (iter->ent->type == TRACE_PRINT && |
2258 | trace_flags & TRACE_ITER_PRINTK && | |
2259 | trace_flags & TRACE_ITER_PRINTK_MSGONLY) | |
5ef841f6 | 2260 | return trace_print_printk_msg_only(iter); |
66896a85 | 2261 | |
cb0f12aa IM |
2262 | if (trace_flags & TRACE_ITER_BIN) |
2263 | return print_bin_fmt(iter); | |
2264 | ||
5e3ca0ec IM |
2265 | if (trace_flags & TRACE_ITER_HEX) |
2266 | return print_hex_fmt(iter); | |
2267 | ||
f9896bf3 IM |
2268 | if (trace_flags & TRACE_ITER_RAW) |
2269 | return print_raw_fmt(iter); | |
2270 | ||
f9896bf3 IM |
2271 | return print_trace_fmt(iter); |
2272 | } | |
2273 | ||
7e9a49ef JO |
2274 | void trace_latency_header(struct seq_file *m) |
2275 | { | |
2276 | struct trace_iterator *iter = m->private; | |
2277 | ||
2278 | /* print nothing if the buffers are empty */ | |
2279 | if (trace_empty(iter)) | |
2280 | return; | |
2281 | ||
2282 | if (iter->iter_flags & TRACE_FILE_LAT_FMT) | |
2283 | print_trace_header(m, iter); | |
2284 | ||
2285 | if (!(trace_flags & TRACE_ITER_VERBOSE)) | |
2286 | print_lat_help_header(m); | |
2287 | } | |
2288 | ||
62b915f1 JO |
2289 | void trace_default_header(struct seq_file *m) |
2290 | { | |
2291 | struct trace_iterator *iter = m->private; | |
2292 | ||
f56e7f8e JO |
2293 | if (!(trace_flags & TRACE_ITER_CONTEXT_INFO)) |
2294 | return; | |
2295 | ||
62b915f1 JO |
2296 | if (iter->iter_flags & TRACE_FILE_LAT_FMT) { |
2297 | /* print nothing if the buffers are empty */ | |
2298 | if (trace_empty(iter)) | |
2299 | return; | |
2300 | print_trace_header(m, iter); | |
2301 | if (!(trace_flags & TRACE_ITER_VERBOSE)) | |
2302 | print_lat_help_header(m); | |
2303 | } else { | |
77271ce4 SR |
2304 | if (!(trace_flags & TRACE_ITER_VERBOSE)) { |
2305 | if (trace_flags & TRACE_ITER_IRQ_INFO) | |
39eaf7ef | 2306 | print_func_help_header_irq(iter->tr, m); |
77271ce4 | 2307 | else |
39eaf7ef | 2308 | print_func_help_header(iter->tr, m); |
77271ce4 | 2309 | } |
62b915f1 JO |
2310 | } |
2311 | } | |
2312 | ||
e0a413f6 SR |
2313 | static void test_ftrace_alive(struct seq_file *m) |
2314 | { | |
2315 | if (!ftrace_is_dead()) | |
2316 | return; | |
2317 | seq_printf(m, "# WARNING: FUNCTION TRACING IS CORRUPTED\n"); | |
2318 | seq_printf(m, "# MAY BE MISSING FUNCTION EVENTS\n"); | |
2319 | } | |
2320 | ||
bc0c38d1 SR |
2321 | static int s_show(struct seq_file *m, void *v) |
2322 | { | |
2323 | struct trace_iterator *iter = v; | |
a63ce5b3 | 2324 | int ret; |
bc0c38d1 SR |
2325 | |
2326 | if (iter->ent == NULL) { | |
2327 | if (iter->tr) { | |
2328 | seq_printf(m, "# tracer: %s\n", iter->trace->name); | |
2329 | seq_puts(m, "#\n"); | |
e0a413f6 | 2330 | test_ftrace_alive(m); |
bc0c38d1 | 2331 | } |
8bba1bf5 MM |
2332 | if (iter->trace && iter->trace->print_header) |
2333 | iter->trace->print_header(m); | |
62b915f1 JO |
2334 | else |
2335 | trace_default_header(m); | |
2336 | ||
a63ce5b3 SR |
2337 | } else if (iter->leftover) { |
2338 | /* | |
2339 | * If we filled the seq_file buffer earlier, we | |
2340 | * want to just show it now. | |
2341 | */ | |
2342 | ret = trace_print_seq(m, &iter->seq); | |
2343 | ||
2344 | /* ret should this time be zero, but you never know */ | |
2345 | iter->leftover = ret; | |
2346 | ||
bc0c38d1 | 2347 | } else { |
f9896bf3 | 2348 | print_trace_line(iter); |
a63ce5b3 SR |
2349 | ret = trace_print_seq(m, &iter->seq); |
2350 | /* | |
2351 | * If we overflow the seq_file buffer, then it will | |
2352 | * ask us for this data again at start up. | |
2353 | * Use that instead. | |
2354 | * ret is 0 if seq_file write succeeded. | |
2355 | * -1 otherwise. | |
2356 | */ | |
2357 | iter->leftover = ret; | |
bc0c38d1 SR |
2358 | } |
2359 | ||
2360 | return 0; | |
2361 | } | |
2362 | ||
88e9d34c | 2363 | static const struct seq_operations tracer_seq_ops = { |
4bf39a94 IM |
2364 | .start = s_start, |
2365 | .next = s_next, | |
2366 | .stop = s_stop, | |
2367 | .show = s_show, | |
bc0c38d1 SR |
2368 | }; |
2369 | ||
e309b41d | 2370 | static struct trace_iterator * |
85a2f9b4 | 2371 | __tracing_open(struct inode *inode, struct file *file) |
bc0c38d1 | 2372 | { |
b04cc6b1 | 2373 | long cpu_file = (long) inode->i_private; |
bc0c38d1 | 2374 | struct trace_iterator *iter; |
50e18b94 | 2375 | int cpu; |
bc0c38d1 | 2376 | |
85a2f9b4 SR |
2377 | if (tracing_disabled) |
2378 | return ERR_PTR(-ENODEV); | |
60a11774 | 2379 | |
50e18b94 | 2380 | iter = __seq_open_private(file, &tracer_seq_ops, sizeof(*iter)); |
85a2f9b4 SR |
2381 | if (!iter) |
2382 | return ERR_PTR(-ENOMEM); | |
bc0c38d1 | 2383 | |
d7350c3f FW |
2384 | /* |
2385 | * We make a copy of the current tracer to avoid concurrent | |
2386 | * changes on it while we are reading. | |
2387 | */ | |
bc0c38d1 | 2388 | mutex_lock(&trace_types_lock); |
d7350c3f | 2389 | iter->trace = kzalloc(sizeof(*iter->trace), GFP_KERNEL); |
85a2f9b4 | 2390 | if (!iter->trace) |
d7350c3f | 2391 | goto fail; |
85a2f9b4 | 2392 | |
d7350c3f FW |
2393 | if (current_trace) |
2394 | *iter->trace = *current_trace; | |
2395 | ||
79f55997 | 2396 | if (!zalloc_cpumask_var(&iter->started, GFP_KERNEL)) |
b0dfa978 FW |
2397 | goto fail; |
2398 | ||
bc0c38d1 SR |
2399 | if (current_trace && current_trace->print_max) |
2400 | iter->tr = &max_tr; | |
2401 | else | |
b04cc6b1 | 2402 | iter->tr = &global_trace; |
bc0c38d1 | 2403 | iter->pos = -1; |
d7350c3f | 2404 | mutex_init(&iter->mutex); |
b04cc6b1 | 2405 | iter->cpu_file = cpu_file; |
bc0c38d1 | 2406 | |
8bba1bf5 MM |
2407 | /* Notify the tracer early; before we stop tracing. */ |
2408 | if (iter->trace && iter->trace->open) | |
a93751ca | 2409 | iter->trace->open(iter); |
8bba1bf5 | 2410 | |
12ef7d44 SR |
2411 | /* Annotate start of buffers if we had overruns */ |
2412 | if (ring_buffer_overruns(iter->tr->buffer)) | |
2413 | iter->iter_flags |= TRACE_FILE_ANNOTATE; | |
2414 | ||
2f26ebd5 SR |
2415 | /* stop the trace while dumping */ |
2416 | tracing_stop(); | |
2417 | ||
b04cc6b1 FW |
2418 | if (iter->cpu_file == TRACE_PIPE_ALL_CPU) { |
2419 | for_each_tracing_cpu(cpu) { | |
b04cc6b1 | 2420 | iter->buffer_iter[cpu] = |
72c9ddfd DM |
2421 | ring_buffer_read_prepare(iter->tr->buffer, cpu); |
2422 | } | |
2423 | ring_buffer_read_prepare_sync(); | |
2424 | for_each_tracing_cpu(cpu) { | |
2425 | ring_buffer_read_start(iter->buffer_iter[cpu]); | |
2f26ebd5 | 2426 | tracing_iter_reset(iter, cpu); |
b04cc6b1 FW |
2427 | } |
2428 | } else { | |
2429 | cpu = iter->cpu_file; | |
3928a8a2 | 2430 | iter->buffer_iter[cpu] = |
72c9ddfd DM |
2431 | ring_buffer_read_prepare(iter->tr->buffer, cpu); |
2432 | ring_buffer_read_prepare_sync(); | |
2433 | ring_buffer_read_start(iter->buffer_iter[cpu]); | |
2f26ebd5 | 2434 | tracing_iter_reset(iter, cpu); |
3928a8a2 SR |
2435 | } |
2436 | ||
bc0c38d1 SR |
2437 | mutex_unlock(&trace_types_lock); |
2438 | ||
bc0c38d1 | 2439 | return iter; |
3928a8a2 | 2440 | |
d7350c3f | 2441 | fail: |
3928a8a2 | 2442 | mutex_unlock(&trace_types_lock); |
d7350c3f | 2443 | kfree(iter->trace); |
50e18b94 JO |
2444 | seq_release_private(inode, file); |
2445 | return ERR_PTR(-ENOMEM); | |
bc0c38d1 SR |
2446 | } |
2447 | ||
2448 | int tracing_open_generic(struct inode *inode, struct file *filp) | |
2449 | { | |
60a11774 SR |
2450 | if (tracing_disabled) |
2451 | return -ENODEV; | |
2452 | ||
bc0c38d1 SR |
2453 | filp->private_data = inode->i_private; |
2454 | return 0; | |
2455 | } | |
2456 | ||
4fd27358 | 2457 | static int tracing_release(struct inode *inode, struct file *file) |
bc0c38d1 | 2458 | { |
907f2784 | 2459 | struct seq_file *m = file->private_data; |
4acd4d00 | 2460 | struct trace_iterator *iter; |
3928a8a2 | 2461 | int cpu; |
bc0c38d1 | 2462 | |
4acd4d00 SR |
2463 | if (!(file->f_mode & FMODE_READ)) |
2464 | return 0; | |
2465 | ||
2466 | iter = m->private; | |
2467 | ||
bc0c38d1 | 2468 | mutex_lock(&trace_types_lock); |
3928a8a2 SR |
2469 | for_each_tracing_cpu(cpu) { |
2470 | if (iter->buffer_iter[cpu]) | |
2471 | ring_buffer_read_finish(iter->buffer_iter[cpu]); | |
2472 | } | |
2473 | ||
bc0c38d1 SR |
2474 | if (iter->trace && iter->trace->close) |
2475 | iter->trace->close(iter); | |
2476 | ||
2477 | /* reenable tracing if it was previously enabled */ | |
9036990d | 2478 | tracing_start(); |
bc0c38d1 SR |
2479 | mutex_unlock(&trace_types_lock); |
2480 | ||
d7350c3f | 2481 | mutex_destroy(&iter->mutex); |
b0dfa978 | 2482 | free_cpumask_var(iter->started); |
d7350c3f | 2483 | kfree(iter->trace); |
50e18b94 | 2484 | seq_release_private(inode, file); |
bc0c38d1 SR |
2485 | return 0; |
2486 | } | |
2487 | ||
2488 | static int tracing_open(struct inode *inode, struct file *file) | |
2489 | { | |
85a2f9b4 SR |
2490 | struct trace_iterator *iter; |
2491 | int ret = 0; | |
bc0c38d1 | 2492 | |
4acd4d00 SR |
2493 | /* If this file was open for write, then erase contents */ |
2494 | if ((file->f_mode & FMODE_WRITE) && | |
8650ae32 | 2495 | (file->f_flags & O_TRUNC)) { |
4acd4d00 | 2496 | long cpu = (long) inode->i_private; |
bc0c38d1 | 2497 | |
4acd4d00 SR |
2498 | if (cpu == TRACE_PIPE_ALL_CPU) |
2499 | tracing_reset_online_cpus(&global_trace); | |
2500 | else | |
2501 | tracing_reset(&global_trace, cpu); | |
2502 | } | |
bc0c38d1 | 2503 | |
4acd4d00 SR |
2504 | if (file->f_mode & FMODE_READ) { |
2505 | iter = __tracing_open(inode, file); | |
2506 | if (IS_ERR(iter)) | |
2507 | ret = PTR_ERR(iter); | |
2508 | else if (trace_flags & TRACE_ITER_LATENCY_FMT) | |
2509 | iter->iter_flags |= TRACE_FILE_LAT_FMT; | |
2510 | } | |
bc0c38d1 SR |
2511 | return ret; |
2512 | } | |
2513 | ||
e309b41d | 2514 | static void * |
bc0c38d1 SR |
2515 | t_next(struct seq_file *m, void *v, loff_t *pos) |
2516 | { | |
f129e965 | 2517 | struct tracer *t = v; |
bc0c38d1 SR |
2518 | |
2519 | (*pos)++; | |
2520 | ||
2521 | if (t) | |
2522 | t = t->next; | |
2523 | ||
bc0c38d1 SR |
2524 | return t; |
2525 | } | |
2526 | ||
2527 | static void *t_start(struct seq_file *m, loff_t *pos) | |
2528 | { | |
f129e965 | 2529 | struct tracer *t; |
bc0c38d1 SR |
2530 | loff_t l = 0; |
2531 | ||
2532 | mutex_lock(&trace_types_lock); | |
f129e965 | 2533 | for (t = trace_types; t && l < *pos; t = t_next(m, t, &l)) |
bc0c38d1 SR |
2534 | ; |
2535 | ||
2536 | return t; | |
2537 | } | |
2538 | ||
2539 | static void t_stop(struct seq_file *m, void *p) | |
2540 | { | |
2541 | mutex_unlock(&trace_types_lock); | |
2542 | } | |
2543 | ||
2544 | static int t_show(struct seq_file *m, void *v) | |
2545 | { | |
2546 | struct tracer *t = v; | |
2547 | ||
2548 | if (!t) | |
2549 | return 0; | |
2550 | ||
2551 | seq_printf(m, "%s", t->name); | |
2552 | if (t->next) | |
2553 | seq_putc(m, ' '); | |
2554 | else | |
2555 | seq_putc(m, '\n'); | |
2556 | ||
2557 | return 0; | |
2558 | } | |
2559 | ||
88e9d34c | 2560 | static const struct seq_operations show_traces_seq_ops = { |
4bf39a94 IM |
2561 | .start = t_start, |
2562 | .next = t_next, | |
2563 | .stop = t_stop, | |
2564 | .show = t_show, | |
bc0c38d1 SR |
2565 | }; |
2566 | ||
2567 | static int show_traces_open(struct inode *inode, struct file *file) | |
2568 | { | |
60a11774 SR |
2569 | if (tracing_disabled) |
2570 | return -ENODEV; | |
2571 | ||
f129e965 | 2572 | return seq_open(file, &show_traces_seq_ops); |
bc0c38d1 SR |
2573 | } |
2574 | ||
4acd4d00 SR |
2575 | static ssize_t |
2576 | tracing_write_stub(struct file *filp, const char __user *ubuf, | |
2577 | size_t count, loff_t *ppos) | |
2578 | { | |
2579 | return count; | |
2580 | } | |
2581 | ||
364829b1 SP |
2582 | static loff_t tracing_seek(struct file *file, loff_t offset, int origin) |
2583 | { | |
2584 | if (file->f_mode & FMODE_READ) | |
2585 | return seq_lseek(file, offset, origin); | |
2586 | else | |
2587 | return 0; | |
2588 | } | |
2589 | ||
5e2336a0 | 2590 | static const struct file_operations tracing_fops = { |
4bf39a94 IM |
2591 | .open = tracing_open, |
2592 | .read = seq_read, | |
4acd4d00 | 2593 | .write = tracing_write_stub, |
364829b1 | 2594 | .llseek = tracing_seek, |
4bf39a94 | 2595 | .release = tracing_release, |
bc0c38d1 SR |
2596 | }; |
2597 | ||
5e2336a0 | 2598 | static const struct file_operations show_traces_fops = { |
c7078de1 IM |
2599 | .open = show_traces_open, |
2600 | .read = seq_read, | |
2601 | .release = seq_release, | |
b444786f | 2602 | .llseek = seq_lseek, |
c7078de1 IM |
2603 | }; |
2604 | ||
36dfe925 IM |
2605 | /* |
2606 | * Only trace on a CPU if the bitmask is set: | |
2607 | */ | |
9e01c1b7 | 2608 | static cpumask_var_t tracing_cpumask; |
36dfe925 IM |
2609 | |
2610 | /* | |
2611 | * The tracer itself will not take this lock, but still we want | |
2612 | * to provide a consistent cpumask to user-space: | |
2613 | */ | |
2614 | static DEFINE_MUTEX(tracing_cpumask_update_lock); | |
2615 | ||
2616 | /* | |
2617 | * Temporary storage for the character representation of the | |
2618 | * CPU bitmask (and one more byte for the newline): | |
2619 | */ | |
2620 | static char mask_str[NR_CPUS + 1]; | |
2621 | ||
c7078de1 IM |
2622 | static ssize_t |
2623 | tracing_cpumask_read(struct file *filp, char __user *ubuf, | |
2624 | size_t count, loff_t *ppos) | |
2625 | { | |
36dfe925 | 2626 | int len; |
c7078de1 IM |
2627 | |
2628 | mutex_lock(&tracing_cpumask_update_lock); | |
36dfe925 | 2629 | |
9e01c1b7 | 2630 | len = cpumask_scnprintf(mask_str, count, tracing_cpumask); |
36dfe925 IM |
2631 | if (count - len < 2) { |
2632 | count = -EINVAL; | |
2633 | goto out_err; | |
2634 | } | |
2635 | len += sprintf(mask_str + len, "\n"); | |
2636 | count = simple_read_from_buffer(ubuf, count, ppos, mask_str, NR_CPUS+1); | |
2637 | ||
2638 | out_err: | |
c7078de1 IM |
2639 | mutex_unlock(&tracing_cpumask_update_lock); |
2640 | ||
2641 | return count; | |
2642 | } | |
2643 | ||
2644 | static ssize_t | |
2645 | tracing_cpumask_write(struct file *filp, const char __user *ubuf, | |
2646 | size_t count, loff_t *ppos) | |
2647 | { | |
36dfe925 | 2648 | int err, cpu; |
9e01c1b7 RR |
2649 | cpumask_var_t tracing_cpumask_new; |
2650 | ||
2651 | if (!alloc_cpumask_var(&tracing_cpumask_new, GFP_KERNEL)) | |
2652 | return -ENOMEM; | |
c7078de1 | 2653 | |
9e01c1b7 | 2654 | err = cpumask_parse_user(ubuf, count, tracing_cpumask_new); |
c7078de1 | 2655 | if (err) |
36dfe925 IM |
2656 | goto err_unlock; |
2657 | ||
215368e8 LZ |
2658 | mutex_lock(&tracing_cpumask_update_lock); |
2659 | ||
a5e25883 | 2660 | local_irq_disable(); |
0199c4e6 | 2661 | arch_spin_lock(&ftrace_max_lock); |
ab46428c | 2662 | for_each_tracing_cpu(cpu) { |
36dfe925 IM |
2663 | /* |
2664 | * Increase/decrease the disabled counter if we are | |
2665 | * about to flip a bit in the cpumask: | |
2666 | */ | |
9e01c1b7 RR |
2667 | if (cpumask_test_cpu(cpu, tracing_cpumask) && |
2668 | !cpumask_test_cpu(cpu, tracing_cpumask_new)) { | |
36dfe925 | 2669 | atomic_inc(&global_trace.data[cpu]->disabled); |
71babb27 | 2670 | ring_buffer_record_disable_cpu(global_trace.buffer, cpu); |
36dfe925 | 2671 | } |
9e01c1b7 RR |
2672 | if (!cpumask_test_cpu(cpu, tracing_cpumask) && |
2673 | cpumask_test_cpu(cpu, tracing_cpumask_new)) { | |
36dfe925 | 2674 | atomic_dec(&global_trace.data[cpu]->disabled); |
71babb27 | 2675 | ring_buffer_record_enable_cpu(global_trace.buffer, cpu); |
36dfe925 IM |
2676 | } |
2677 | } | |
0199c4e6 | 2678 | arch_spin_unlock(&ftrace_max_lock); |
a5e25883 | 2679 | local_irq_enable(); |
36dfe925 | 2680 | |
9e01c1b7 | 2681 | cpumask_copy(tracing_cpumask, tracing_cpumask_new); |
36dfe925 IM |
2682 | |
2683 | mutex_unlock(&tracing_cpumask_update_lock); | |
9e01c1b7 | 2684 | free_cpumask_var(tracing_cpumask_new); |
c7078de1 IM |
2685 | |
2686 | return count; | |
36dfe925 IM |
2687 | |
2688 | err_unlock: | |
215368e8 | 2689 | free_cpumask_var(tracing_cpumask_new); |
36dfe925 IM |
2690 | |
2691 | return err; | |
c7078de1 IM |
2692 | } |
2693 | ||
5e2336a0 | 2694 | static const struct file_operations tracing_cpumask_fops = { |
c7078de1 IM |
2695 | .open = tracing_open_generic, |
2696 | .read = tracing_cpumask_read, | |
2697 | .write = tracing_cpumask_write, | |
b444786f | 2698 | .llseek = generic_file_llseek, |
bc0c38d1 SR |
2699 | }; |
2700 | ||
fdb372ed | 2701 | static int tracing_trace_options_show(struct seq_file *m, void *v) |
bc0c38d1 | 2702 | { |
d8e83d26 SR |
2703 | struct tracer_opt *trace_opts; |
2704 | u32 tracer_flags; | |
d8e83d26 | 2705 | int i; |
adf9f195 | 2706 | |
d8e83d26 SR |
2707 | mutex_lock(&trace_types_lock); |
2708 | tracer_flags = current_trace->flags->val; | |
2709 | trace_opts = current_trace->flags->opts; | |
2710 | ||
bc0c38d1 SR |
2711 | for (i = 0; trace_options[i]; i++) { |
2712 | if (trace_flags & (1 << i)) | |
fdb372ed | 2713 | seq_printf(m, "%s\n", trace_options[i]); |
bc0c38d1 | 2714 | else |
fdb372ed | 2715 | seq_printf(m, "no%s\n", trace_options[i]); |
bc0c38d1 SR |
2716 | } |
2717 | ||
adf9f195 FW |
2718 | for (i = 0; trace_opts[i].name; i++) { |
2719 | if (tracer_flags & trace_opts[i].bit) | |
fdb372ed | 2720 | seq_printf(m, "%s\n", trace_opts[i].name); |
adf9f195 | 2721 | else |
fdb372ed | 2722 | seq_printf(m, "no%s\n", trace_opts[i].name); |
adf9f195 | 2723 | } |
d8e83d26 | 2724 | mutex_unlock(&trace_types_lock); |
adf9f195 | 2725 | |
fdb372ed | 2726 | return 0; |
bc0c38d1 | 2727 | } |
bc0c38d1 | 2728 | |
8d18eaaf LZ |
2729 | static int __set_tracer_option(struct tracer *trace, |
2730 | struct tracer_flags *tracer_flags, | |
2731 | struct tracer_opt *opts, int neg) | |
2732 | { | |
2733 | int ret; | |
bc0c38d1 | 2734 | |
8d18eaaf LZ |
2735 | ret = trace->set_flag(tracer_flags->val, opts->bit, !neg); |
2736 | if (ret) | |
2737 | return ret; | |
2738 | ||
2739 | if (neg) | |
2740 | tracer_flags->val &= ~opts->bit; | |
2741 | else | |
2742 | tracer_flags->val |= opts->bit; | |
2743 | return 0; | |
bc0c38d1 SR |
2744 | } |
2745 | ||
adf9f195 FW |
2746 | /* Try to assign a tracer specific option */ |
2747 | static int set_tracer_option(struct tracer *trace, char *cmp, int neg) | |
2748 | { | |
7770841e | 2749 | struct tracer_flags *tracer_flags = trace->flags; |
adf9f195 | 2750 | struct tracer_opt *opts = NULL; |
8d18eaaf | 2751 | int i; |
adf9f195 | 2752 | |
7770841e Z |
2753 | for (i = 0; tracer_flags->opts[i].name; i++) { |
2754 | opts = &tracer_flags->opts[i]; | |
adf9f195 | 2755 | |
8d18eaaf LZ |
2756 | if (strcmp(cmp, opts->name) == 0) |
2757 | return __set_tracer_option(trace, trace->flags, | |
2758 | opts, neg); | |
adf9f195 | 2759 | } |
adf9f195 | 2760 | |
8d18eaaf | 2761 | return -EINVAL; |
adf9f195 FW |
2762 | } |
2763 | ||
af4617bd SR |
2764 | static void set_tracer_flags(unsigned int mask, int enabled) |
2765 | { | |
2766 | /* do nothing if flag is already set */ | |
2767 | if (!!(trace_flags & mask) == !!enabled) | |
2768 | return; | |
2769 | ||
2770 | if (enabled) | |
2771 | trace_flags |= mask; | |
2772 | else | |
2773 | trace_flags &= ~mask; | |
e870e9a1 LZ |
2774 | |
2775 | if (mask == TRACE_ITER_RECORD_CMD) | |
2776 | trace_event_enable_cmd_record(enabled); | |
750912fa DS |
2777 | |
2778 | if (mask == TRACE_ITER_OVERWRITE) | |
2779 | ring_buffer_change_overwrite(global_trace.buffer, enabled); | |
af4617bd SR |
2780 | } |
2781 | ||
bc0c38d1 | 2782 | static ssize_t |
ee6bce52 | 2783 | tracing_trace_options_write(struct file *filp, const char __user *ubuf, |
bc0c38d1 SR |
2784 | size_t cnt, loff_t *ppos) |
2785 | { | |
2786 | char buf[64]; | |
8d18eaaf | 2787 | char *cmp; |
bc0c38d1 | 2788 | int neg = 0; |
adf9f195 | 2789 | int ret; |
bc0c38d1 SR |
2790 | int i; |
2791 | ||
cffae437 SR |
2792 | if (cnt >= sizeof(buf)) |
2793 | return -EINVAL; | |
bc0c38d1 SR |
2794 | |
2795 | if (copy_from_user(&buf, ubuf, cnt)) | |
2796 | return -EFAULT; | |
2797 | ||
2798 | buf[cnt] = 0; | |
8d18eaaf | 2799 | cmp = strstrip(buf); |
bc0c38d1 | 2800 | |
8d18eaaf | 2801 | if (strncmp(cmp, "no", 2) == 0) { |
bc0c38d1 SR |
2802 | neg = 1; |
2803 | cmp += 2; | |
2804 | } | |
2805 | ||
2806 | for (i = 0; trace_options[i]; i++) { | |
8d18eaaf | 2807 | if (strcmp(cmp, trace_options[i]) == 0) { |
af4617bd | 2808 | set_tracer_flags(1 << i, !neg); |
bc0c38d1 SR |
2809 | break; |
2810 | } | |
2811 | } | |
adf9f195 FW |
2812 | |
2813 | /* If no option could be set, test the specific tracer options */ | |
2814 | if (!trace_options[i]) { | |
d8e83d26 | 2815 | mutex_lock(&trace_types_lock); |
adf9f195 | 2816 | ret = set_tracer_option(current_trace, cmp, neg); |
d8e83d26 | 2817 | mutex_unlock(&trace_types_lock); |
adf9f195 FW |
2818 | if (ret) |
2819 | return ret; | |
2820 | } | |
bc0c38d1 | 2821 | |
cf8517cf | 2822 | *ppos += cnt; |
bc0c38d1 SR |
2823 | |
2824 | return cnt; | |
2825 | } | |
2826 | ||
fdb372ed LZ |
2827 | static int tracing_trace_options_open(struct inode *inode, struct file *file) |
2828 | { | |
2829 | if (tracing_disabled) | |
2830 | return -ENODEV; | |
2831 | return single_open(file, tracing_trace_options_show, NULL); | |
2832 | } | |
2833 | ||
5e2336a0 | 2834 | static const struct file_operations tracing_iter_fops = { |
fdb372ed LZ |
2835 | .open = tracing_trace_options_open, |
2836 | .read = seq_read, | |
2837 | .llseek = seq_lseek, | |
2838 | .release = single_release, | |
ee6bce52 | 2839 | .write = tracing_trace_options_write, |
bc0c38d1 SR |
2840 | }; |
2841 | ||
7bd2f24c IM |
2842 | static const char readme_msg[] = |
2843 | "tracing mini-HOWTO:\n\n" | |
156f5a78 GL |
2844 | "# mount -t debugfs nodev /sys/kernel/debug\n\n" |
2845 | "# cat /sys/kernel/debug/tracing/available_tracers\n" | |
1e42e83f | 2846 | "wakeup wakeup_rt preemptirqsoff preemptoff irqsoff function nop\n\n" |
156f5a78 | 2847 | "# cat /sys/kernel/debug/tracing/current_tracer\n" |
bc2b6871 | 2848 | "nop\n" |
1e42e83f | 2849 | "# echo wakeup > /sys/kernel/debug/tracing/current_tracer\n" |
156f5a78 | 2850 | "# cat /sys/kernel/debug/tracing/current_tracer\n" |
1e42e83f | 2851 | "wakeup\n" |
156f5a78 | 2852 | "# cat /sys/kernel/debug/tracing/trace_options\n" |
7bd2f24c | 2853 | "noprint-parent nosym-offset nosym-addr noverbose\n" |
156f5a78 | 2854 | "# echo print-parent > /sys/kernel/debug/tracing/trace_options\n" |
9b5f8b31 | 2855 | "# echo 1 > /sys/kernel/debug/tracing/tracing_on\n" |
156f5a78 | 2856 | "# cat /sys/kernel/debug/tracing/trace > /tmp/trace.txt\n" |
9b5f8b31 | 2857 | "# echo 0 > /sys/kernel/debug/tracing/tracing_on\n" |
7bd2f24c IM |
2858 | ; |
2859 | ||
2860 | static ssize_t | |
2861 | tracing_readme_read(struct file *filp, char __user *ubuf, | |
2862 | size_t cnt, loff_t *ppos) | |
2863 | { | |
2864 | return simple_read_from_buffer(ubuf, cnt, ppos, | |
2865 | readme_msg, strlen(readme_msg)); | |
2866 | } | |
2867 | ||
5e2336a0 | 2868 | static const struct file_operations tracing_readme_fops = { |
c7078de1 IM |
2869 | .open = tracing_open_generic, |
2870 | .read = tracing_readme_read, | |
b444786f | 2871 | .llseek = generic_file_llseek, |
7bd2f24c IM |
2872 | }; |
2873 | ||
69abe6a5 AP |
2874 | static ssize_t |
2875 | tracing_saved_cmdlines_read(struct file *file, char __user *ubuf, | |
2876 | size_t cnt, loff_t *ppos) | |
2877 | { | |
2878 | char *buf_comm; | |
2879 | char *file_buf; | |
2880 | char *buf; | |
2881 | int len = 0; | |
2882 | int pid; | |
2883 | int i; | |
2884 | ||
2885 | file_buf = kmalloc(SAVED_CMDLINES*(16+TASK_COMM_LEN), GFP_KERNEL); | |
2886 | if (!file_buf) | |
2887 | return -ENOMEM; | |
2888 | ||
2889 | buf_comm = kmalloc(TASK_COMM_LEN, GFP_KERNEL); | |
2890 | if (!buf_comm) { | |
2891 | kfree(file_buf); | |
2892 | return -ENOMEM; | |
2893 | } | |
2894 | ||
2895 | buf = file_buf; | |
2896 | ||
2897 | for (i = 0; i < SAVED_CMDLINES; i++) { | |
2898 | int r; | |
2899 | ||
2900 | pid = map_cmdline_to_pid[i]; | |
2901 | if (pid == -1 || pid == NO_CMDLINE_MAP) | |
2902 | continue; | |
2903 | ||
2904 | trace_find_cmdline(pid, buf_comm); | |
2905 | r = sprintf(buf, "%d %s\n", pid, buf_comm); | |
2906 | buf += r; | |
2907 | len += r; | |
2908 | } | |
2909 | ||
2910 | len = simple_read_from_buffer(ubuf, cnt, ppos, | |
2911 | file_buf, len); | |
2912 | ||
2913 | kfree(file_buf); | |
2914 | kfree(buf_comm); | |
2915 | ||
2916 | return len; | |
2917 | } | |
2918 | ||
2919 | static const struct file_operations tracing_saved_cmdlines_fops = { | |
2920 | .open = tracing_open_generic, | |
2921 | .read = tracing_saved_cmdlines_read, | |
b444786f | 2922 | .llseek = generic_file_llseek, |
69abe6a5 AP |
2923 | }; |
2924 | ||
bc0c38d1 SR |
2925 | static ssize_t |
2926 | tracing_ctrl_read(struct file *filp, char __user *ubuf, | |
2927 | size_t cnt, loff_t *ppos) | |
2928 | { | |
bc0c38d1 SR |
2929 | char buf[64]; |
2930 | int r; | |
2931 | ||
9036990d | 2932 | r = sprintf(buf, "%u\n", tracer_enabled); |
4e3c3333 | 2933 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, r); |
bc0c38d1 SR |
2934 | } |
2935 | ||
2936 | static ssize_t | |
2937 | tracing_ctrl_write(struct file *filp, const char __user *ubuf, | |
2938 | size_t cnt, loff_t *ppos) | |
2939 | { | |
2940 | struct trace_array *tr = filp->private_data; | |
5e39841c | 2941 | unsigned long val; |
c6caeeb1 | 2942 | int ret; |
bc0c38d1 | 2943 | |
22fe9b54 PH |
2944 | ret = kstrtoul_from_user(ubuf, cnt, 10, &val); |
2945 | if (ret) | |
c6caeeb1 | 2946 | return ret; |
bc0c38d1 SR |
2947 | |
2948 | val = !!val; | |
2949 | ||
2950 | mutex_lock(&trace_types_lock); | |
9036990d | 2951 | if (tracer_enabled ^ val) { |
6752ab4a SR |
2952 | |
2953 | /* Only need to warn if this is used to change the state */ | |
2954 | WARN_ONCE(1, "tracing_enabled is deprecated. Use tracing_on"); | |
2955 | ||
9036990d | 2956 | if (val) { |
bc0c38d1 | 2957 | tracer_enabled = 1; |
9036990d SR |
2958 | if (current_trace->start) |
2959 | current_trace->start(tr); | |
2960 | tracing_start(); | |
2961 | } else { | |
bc0c38d1 | 2962 | tracer_enabled = 0; |
9036990d SR |
2963 | tracing_stop(); |
2964 | if (current_trace->stop) | |
2965 | current_trace->stop(tr); | |
2966 | } | |
bc0c38d1 SR |
2967 | } |
2968 | mutex_unlock(&trace_types_lock); | |
2969 | ||
cf8517cf | 2970 | *ppos += cnt; |
bc0c38d1 SR |
2971 | |
2972 | return cnt; | |
2973 | } | |
2974 | ||
2975 | static ssize_t | |
2976 | tracing_set_trace_read(struct file *filp, char __user *ubuf, | |
2977 | size_t cnt, loff_t *ppos) | |
2978 | { | |
ee6c2c1b | 2979 | char buf[MAX_TRACER_SIZE+2]; |
bc0c38d1 SR |
2980 | int r; |
2981 | ||
2982 | mutex_lock(&trace_types_lock); | |
2983 | if (current_trace) | |
2984 | r = sprintf(buf, "%s\n", current_trace->name); | |
2985 | else | |
2986 | r = sprintf(buf, "\n"); | |
2987 | mutex_unlock(&trace_types_lock); | |
2988 | ||
4bf39a94 | 2989 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, r); |
bc0c38d1 SR |
2990 | } |
2991 | ||
b6f11df2 ACM |
2992 | int tracer_init(struct tracer *t, struct trace_array *tr) |
2993 | { | |
2994 | tracing_reset_online_cpus(tr); | |
2995 | return t->init(tr); | |
2996 | } | |
2997 | ||
438ced17 VN |
2998 | static void set_buffer_entries(struct trace_array *tr, unsigned long val) |
2999 | { | |
3000 | int cpu; | |
3001 | for_each_tracing_cpu(cpu) | |
3002 | tr->data[cpu]->entries = val; | |
3003 | } | |
3004 | ||
3005 | static int __tracing_resize_ring_buffer(unsigned long size, int cpu) | |
73c5162a SR |
3006 | { |
3007 | int ret; | |
3008 | ||
3009 | /* | |
3010 | * If kernel or user changes the size of the ring buffer | |
a123c52b SR |
3011 | * we use the size that was given, and we can forget about |
3012 | * expanding it later. | |
73c5162a SR |
3013 | */ |
3014 | ring_buffer_expanded = 1; | |
3015 | ||
438ced17 | 3016 | ret = ring_buffer_resize(global_trace.buffer, size, cpu); |
73c5162a SR |
3017 | if (ret < 0) |
3018 | return ret; | |
3019 | ||
ef710e10 KM |
3020 | if (!current_trace->use_max_tr) |
3021 | goto out; | |
3022 | ||
438ced17 | 3023 | ret = ring_buffer_resize(max_tr.buffer, size, cpu); |
73c5162a | 3024 | if (ret < 0) { |
438ced17 VN |
3025 | int r = 0; |
3026 | ||
3027 | if (cpu == RING_BUFFER_ALL_CPUS) { | |
3028 | int i; | |
3029 | for_each_tracing_cpu(i) { | |
3030 | r = ring_buffer_resize(global_trace.buffer, | |
3031 | global_trace.data[i]->entries, | |
3032 | i); | |
3033 | if (r < 0) | |
3034 | break; | |
3035 | } | |
3036 | } else { | |
3037 | r = ring_buffer_resize(global_trace.buffer, | |
3038 | global_trace.data[cpu]->entries, | |
3039 | cpu); | |
3040 | } | |
73c5162a | 3041 | |
73c5162a | 3042 | if (r < 0) { |
a123c52b SR |
3043 | /* |
3044 | * AARGH! We are left with different | |
3045 | * size max buffer!!!! | |
3046 | * The max buffer is our "snapshot" buffer. | |
3047 | * When a tracer needs a snapshot (one of the | |
3048 | * latency tracers), it swaps the max buffer | |
3049 | * with the saved snap shot. We succeeded to | |
3050 | * update the size of the main buffer, but failed to | |
3051 | * update the size of the max buffer. But when we tried | |
3052 | * to reset the main buffer to the original size, we | |
3053 | * failed there too. This is very unlikely to | |
3054 | * happen, but if it does, warn and kill all | |
3055 | * tracing. | |
3056 | */ | |
73c5162a SR |
3057 | WARN_ON(1); |
3058 | tracing_disabled = 1; | |
3059 | } | |
3060 | return ret; | |
3061 | } | |
3062 | ||
438ced17 VN |
3063 | if (cpu == RING_BUFFER_ALL_CPUS) |
3064 | set_buffer_entries(&max_tr, size); | |
3065 | else | |
3066 | max_tr.data[cpu]->entries = size; | |
3067 | ||
ef710e10 | 3068 | out: |
438ced17 VN |
3069 | if (cpu == RING_BUFFER_ALL_CPUS) |
3070 | set_buffer_entries(&global_trace, size); | |
3071 | else | |
3072 | global_trace.data[cpu]->entries = size; | |
73c5162a SR |
3073 | |
3074 | return ret; | |
3075 | } | |
3076 | ||
438ced17 | 3077 | static ssize_t tracing_resize_ring_buffer(unsigned long size, int cpu_id) |
4f271a2a | 3078 | { |
83f40318 | 3079 | int ret = size; |
4f271a2a VN |
3080 | |
3081 | mutex_lock(&trace_types_lock); | |
3082 | ||
438ced17 VN |
3083 | if (cpu_id != RING_BUFFER_ALL_CPUS) { |
3084 | /* make sure, this cpu is enabled in the mask */ | |
3085 | if (!cpumask_test_cpu(cpu_id, tracing_buffer_mask)) { | |
3086 | ret = -EINVAL; | |
3087 | goto out; | |
3088 | } | |
3089 | } | |
4f271a2a | 3090 | |
438ced17 | 3091 | ret = __tracing_resize_ring_buffer(size, cpu_id); |
4f271a2a VN |
3092 | if (ret < 0) |
3093 | ret = -ENOMEM; | |
3094 | ||
438ced17 | 3095 | out: |
4f271a2a VN |
3096 | mutex_unlock(&trace_types_lock); |
3097 | ||
3098 | return ret; | |
3099 | } | |
3100 | ||
ef710e10 | 3101 | |
1852fcce SR |
3102 | /** |
3103 | * tracing_update_buffers - used by tracing facility to expand ring buffers | |
3104 | * | |
3105 | * To save on memory when the tracing is never used on a system with it | |
3106 | * configured in. The ring buffers are set to a minimum size. But once | |
3107 | * a user starts to use the tracing facility, then they need to grow | |
3108 | * to their default size. | |
3109 | * | |
3110 | * This function is to be called when a tracer is about to be used. | |
3111 | */ | |
3112 | int tracing_update_buffers(void) | |
3113 | { | |
3114 | int ret = 0; | |
3115 | ||
1027fcb2 | 3116 | mutex_lock(&trace_types_lock); |
1852fcce | 3117 | if (!ring_buffer_expanded) |
438ced17 VN |
3118 | ret = __tracing_resize_ring_buffer(trace_buf_size, |
3119 | RING_BUFFER_ALL_CPUS); | |
1027fcb2 | 3120 | mutex_unlock(&trace_types_lock); |
1852fcce SR |
3121 | |
3122 | return ret; | |
3123 | } | |
3124 | ||
577b785f SR |
3125 | struct trace_option_dentry; |
3126 | ||
3127 | static struct trace_option_dentry * | |
3128 | create_trace_option_files(struct tracer *tracer); | |
3129 | ||
3130 | static void | |
3131 | destroy_trace_option_files(struct trace_option_dentry *topts); | |
3132 | ||
b2821ae6 | 3133 | static int tracing_set_tracer(const char *buf) |
bc0c38d1 | 3134 | { |
577b785f | 3135 | static struct trace_option_dentry *topts; |
bc0c38d1 SR |
3136 | struct trace_array *tr = &global_trace; |
3137 | struct tracer *t; | |
d9e54076 | 3138 | int ret = 0; |
bc0c38d1 | 3139 | |
1027fcb2 SR |
3140 | mutex_lock(&trace_types_lock); |
3141 | ||
73c5162a | 3142 | if (!ring_buffer_expanded) { |
438ced17 VN |
3143 | ret = __tracing_resize_ring_buffer(trace_buf_size, |
3144 | RING_BUFFER_ALL_CPUS); | |
73c5162a | 3145 | if (ret < 0) |
59f586db | 3146 | goto out; |
73c5162a SR |
3147 | ret = 0; |
3148 | } | |
3149 | ||
bc0c38d1 SR |
3150 | for (t = trace_types; t; t = t->next) { |
3151 | if (strcmp(t->name, buf) == 0) | |
3152 | break; | |
3153 | } | |
c2931e05 FW |
3154 | if (!t) { |
3155 | ret = -EINVAL; | |
3156 | goto out; | |
3157 | } | |
3158 | if (t == current_trace) | |
bc0c38d1 SR |
3159 | goto out; |
3160 | ||
9f029e83 | 3161 | trace_branch_disable(); |
bc0c38d1 SR |
3162 | if (current_trace && current_trace->reset) |
3163 | current_trace->reset(tr); | |
ef710e10 KM |
3164 | if (current_trace && current_trace->use_max_tr) { |
3165 | /* | |
3166 | * We don't free the ring buffer. instead, resize it because | |
3167 | * The max_tr ring buffer has some state (e.g. ring->clock) and | |
3168 | * we want preserve it. | |
3169 | */ | |
438ced17 VN |
3170 | ring_buffer_resize(max_tr.buffer, 1, RING_BUFFER_ALL_CPUS); |
3171 | set_buffer_entries(&max_tr, 1); | |
ef710e10 | 3172 | } |
577b785f SR |
3173 | destroy_trace_option_files(topts); |
3174 | ||
bc0c38d1 | 3175 | current_trace = t; |
577b785f SR |
3176 | |
3177 | topts = create_trace_option_files(current_trace); | |
ef710e10 | 3178 | if (current_trace->use_max_tr) { |
438ced17 VN |
3179 | int cpu; |
3180 | /* we need to make per cpu buffer sizes equivalent */ | |
3181 | for_each_tracing_cpu(cpu) { | |
3182 | ret = ring_buffer_resize(max_tr.buffer, | |
3183 | global_trace.data[cpu]->entries, | |
3184 | cpu); | |
3185 | if (ret < 0) | |
3186 | goto out; | |
3187 | max_tr.data[cpu]->entries = | |
3188 | global_trace.data[cpu]->entries; | |
3189 | } | |
ef710e10 | 3190 | } |
577b785f | 3191 | |
1c80025a | 3192 | if (t->init) { |
b6f11df2 | 3193 | ret = tracer_init(t, tr); |
1c80025a FW |
3194 | if (ret) |
3195 | goto out; | |
3196 | } | |
bc0c38d1 | 3197 | |
9f029e83 | 3198 | trace_branch_enable(tr); |
bc0c38d1 SR |
3199 | out: |
3200 | mutex_unlock(&trace_types_lock); | |
3201 | ||
d9e54076 PZ |
3202 | return ret; |
3203 | } | |
3204 | ||
3205 | static ssize_t | |
3206 | tracing_set_trace_write(struct file *filp, const char __user *ubuf, | |
3207 | size_t cnt, loff_t *ppos) | |
3208 | { | |
ee6c2c1b | 3209 | char buf[MAX_TRACER_SIZE+1]; |
d9e54076 PZ |
3210 | int i; |
3211 | size_t ret; | |
e6e7a65a FW |
3212 | int err; |
3213 | ||
3214 | ret = cnt; | |
d9e54076 | 3215 | |
ee6c2c1b LZ |
3216 | if (cnt > MAX_TRACER_SIZE) |
3217 | cnt = MAX_TRACER_SIZE; | |
d9e54076 PZ |
3218 | |
3219 | if (copy_from_user(&buf, ubuf, cnt)) | |
3220 | return -EFAULT; | |
3221 | ||
3222 | buf[cnt] = 0; | |
3223 | ||
3224 | /* strip ending whitespace. */ | |
3225 | for (i = cnt - 1; i > 0 && isspace(buf[i]); i--) | |
3226 | buf[i] = 0; | |
3227 | ||
e6e7a65a FW |
3228 | err = tracing_set_tracer(buf); |
3229 | if (err) | |
3230 | return err; | |
d9e54076 | 3231 | |
cf8517cf | 3232 | *ppos += ret; |
bc0c38d1 | 3233 | |
c2931e05 | 3234 | return ret; |
bc0c38d1 SR |
3235 | } |
3236 | ||
3237 | static ssize_t | |
3238 | tracing_max_lat_read(struct file *filp, char __user *ubuf, | |
3239 | size_t cnt, loff_t *ppos) | |
3240 | { | |
3241 | unsigned long *ptr = filp->private_data; | |
3242 | char buf[64]; | |
3243 | int r; | |
3244 | ||
cffae437 | 3245 | r = snprintf(buf, sizeof(buf), "%ld\n", |
bc0c38d1 | 3246 | *ptr == (unsigned long)-1 ? -1 : nsecs_to_usecs(*ptr)); |
cffae437 SR |
3247 | if (r > sizeof(buf)) |
3248 | r = sizeof(buf); | |
4bf39a94 | 3249 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, r); |
bc0c38d1 SR |
3250 | } |
3251 | ||
3252 | static ssize_t | |
3253 | tracing_max_lat_write(struct file *filp, const char __user *ubuf, | |
3254 | size_t cnt, loff_t *ppos) | |
3255 | { | |
5e39841c | 3256 | unsigned long *ptr = filp->private_data; |
5e39841c | 3257 | unsigned long val; |
c6caeeb1 | 3258 | int ret; |
bc0c38d1 | 3259 | |
22fe9b54 PH |
3260 | ret = kstrtoul_from_user(ubuf, cnt, 10, &val); |
3261 | if (ret) | |
c6caeeb1 | 3262 | return ret; |
bc0c38d1 SR |
3263 | |
3264 | *ptr = val * 1000; | |
3265 | ||
3266 | return cnt; | |
3267 | } | |
3268 | ||
b3806b43 SR |
3269 | static int tracing_open_pipe(struct inode *inode, struct file *filp) |
3270 | { | |
b04cc6b1 | 3271 | long cpu_file = (long) inode->i_private; |
b3806b43 | 3272 | struct trace_iterator *iter; |
b04cc6b1 | 3273 | int ret = 0; |
b3806b43 SR |
3274 | |
3275 | if (tracing_disabled) | |
3276 | return -ENODEV; | |
3277 | ||
b04cc6b1 FW |
3278 | mutex_lock(&trace_types_lock); |
3279 | ||
b3806b43 SR |
3280 | /* create a buffer to store the information to pass to userspace */ |
3281 | iter = kzalloc(sizeof(*iter), GFP_KERNEL); | |
b04cc6b1 FW |
3282 | if (!iter) { |
3283 | ret = -ENOMEM; | |
3284 | goto out; | |
3285 | } | |
b3806b43 | 3286 | |
d7350c3f FW |
3287 | /* |
3288 | * We make a copy of the current tracer to avoid concurrent | |
3289 | * changes on it while we are reading. | |
3290 | */ | |
3291 | iter->trace = kmalloc(sizeof(*iter->trace), GFP_KERNEL); | |
3292 | if (!iter->trace) { | |
3293 | ret = -ENOMEM; | |
3294 | goto fail; | |
3295 | } | |
3296 | if (current_trace) | |
3297 | *iter->trace = *current_trace; | |
3298 | ||
4462344e | 3299 | if (!alloc_cpumask_var(&iter->started, GFP_KERNEL)) { |
b04cc6b1 | 3300 | ret = -ENOMEM; |
d7350c3f | 3301 | goto fail; |
4462344e RR |
3302 | } |
3303 | ||
a309720c | 3304 | /* trace pipe does not show start of buffer */ |
4462344e | 3305 | cpumask_setall(iter->started); |
a309720c | 3306 | |
112f38a7 SR |
3307 | if (trace_flags & TRACE_ITER_LATENCY_FMT) |
3308 | iter->iter_flags |= TRACE_FILE_LAT_FMT; | |
3309 | ||
b04cc6b1 | 3310 | iter->cpu_file = cpu_file; |
b3806b43 | 3311 | iter->tr = &global_trace; |
d7350c3f | 3312 | mutex_init(&iter->mutex); |
b3806b43 SR |
3313 | filp->private_data = iter; |
3314 | ||
107bad8b SR |
3315 | if (iter->trace->pipe_open) |
3316 | iter->trace->pipe_open(iter); | |
107bad8b | 3317 | |
b444786f | 3318 | nonseekable_open(inode, filp); |
b04cc6b1 FW |
3319 | out: |
3320 | mutex_unlock(&trace_types_lock); | |
3321 | return ret; | |
d7350c3f FW |
3322 | |
3323 | fail: | |
3324 | kfree(iter->trace); | |
3325 | kfree(iter); | |
3326 | mutex_unlock(&trace_types_lock); | |
3327 | return ret; | |
b3806b43 SR |
3328 | } |
3329 | ||
3330 | static int tracing_release_pipe(struct inode *inode, struct file *file) | |
3331 | { | |
3332 | struct trace_iterator *iter = file->private_data; | |
3333 | ||
b04cc6b1 FW |
3334 | mutex_lock(&trace_types_lock); |
3335 | ||
29bf4a5e | 3336 | if (iter->trace->pipe_close) |
c521efd1 SR |
3337 | iter->trace->pipe_close(iter); |
3338 | ||
b04cc6b1 FW |
3339 | mutex_unlock(&trace_types_lock); |
3340 | ||
4462344e | 3341 | free_cpumask_var(iter->started); |
d7350c3f FW |
3342 | mutex_destroy(&iter->mutex); |
3343 | kfree(iter->trace); | |
b3806b43 | 3344 | kfree(iter); |
b3806b43 SR |
3345 | |
3346 | return 0; | |
3347 | } | |
3348 | ||
2a2cc8f7 SSP |
3349 | static unsigned int |
3350 | tracing_poll_pipe(struct file *filp, poll_table *poll_table) | |
3351 | { | |
3352 | struct trace_iterator *iter = filp->private_data; | |
3353 | ||
3354 | if (trace_flags & TRACE_ITER_BLOCK) { | |
3355 | /* | |
3356 | * Always select as readable when in blocking mode | |
3357 | */ | |
3358 | return POLLIN | POLLRDNORM; | |
afc2abc0 | 3359 | } else { |
2a2cc8f7 SSP |
3360 | if (!trace_empty(iter)) |
3361 | return POLLIN | POLLRDNORM; | |
3362 | poll_wait(filp, &trace_wait, poll_table); | |
3363 | if (!trace_empty(iter)) | |
3364 | return POLLIN | POLLRDNORM; | |
3365 | ||
3366 | return 0; | |
3367 | } | |
3368 | } | |
3369 | ||
6eaaa5d5 FW |
3370 | |
3371 | void default_wait_pipe(struct trace_iterator *iter) | |
3372 | { | |
3373 | DEFINE_WAIT(wait); | |
3374 | ||
3375 | prepare_to_wait(&trace_wait, &wait, TASK_INTERRUPTIBLE); | |
3376 | ||
3377 | if (trace_empty(iter)) | |
3378 | schedule(); | |
3379 | ||
3380 | finish_wait(&trace_wait, &wait); | |
3381 | } | |
3382 | ||
3383 | /* | |
3384 | * This is a make-shift waitqueue. | |
3385 | * A tracer might use this callback on some rare cases: | |
3386 | * | |
3387 | * 1) the current tracer might hold the runqueue lock when it wakes up | |
3388 | * a reader, hence a deadlock (sched, function, and function graph tracers) | |
3389 | * 2) the function tracers, trace all functions, we don't want | |
3390 | * the overhead of calling wake_up and friends | |
3391 | * (and tracing them too) | |
3392 | * | |
3393 | * Anyway, this is really very primitive wakeup. | |
3394 | */ | |
3395 | void poll_wait_pipe(struct trace_iterator *iter) | |
3396 | { | |
3397 | set_current_state(TASK_INTERRUPTIBLE); | |
3398 | /* sleep for 100 msecs, and try again. */ | |
3399 | schedule_timeout(HZ / 10); | |
3400 | } | |
3401 | ||
ff98781b EGM |
3402 | /* Must be called with trace_types_lock mutex held. */ |
3403 | static int tracing_wait_pipe(struct file *filp) | |
b3806b43 SR |
3404 | { |
3405 | struct trace_iterator *iter = filp->private_data; | |
b3806b43 | 3406 | |
b3806b43 | 3407 | while (trace_empty(iter)) { |
2dc8f095 | 3408 | |
107bad8b | 3409 | if ((filp->f_flags & O_NONBLOCK)) { |
ff98781b | 3410 | return -EAGAIN; |
107bad8b | 3411 | } |
2dc8f095 | 3412 | |
d7350c3f | 3413 | mutex_unlock(&iter->mutex); |
107bad8b | 3414 | |
6eaaa5d5 | 3415 | iter->trace->wait_pipe(iter); |
b3806b43 | 3416 | |
d7350c3f | 3417 | mutex_lock(&iter->mutex); |
107bad8b | 3418 | |
6eaaa5d5 | 3419 | if (signal_pending(current)) |
ff98781b | 3420 | return -EINTR; |
b3806b43 SR |
3421 | |
3422 | /* | |
3423 | * We block until we read something and tracing is disabled. | |
3424 | * We still block if tracing is disabled, but we have never | |
3425 | * read anything. This allows a user to cat this file, and | |
3426 | * then enable tracing. But after we have read something, | |
3427 | * we give an EOF when tracing is again disabled. | |
3428 | * | |
3429 | * iter->pos will be 0 if we haven't read anything. | |
3430 | */ | |
3431 | if (!tracer_enabled && iter->pos) | |
3432 | break; | |
b3806b43 SR |
3433 | } |
3434 | ||
ff98781b EGM |
3435 | return 1; |
3436 | } | |
3437 | ||
3438 | /* | |
3439 | * Consumer reader. | |
3440 | */ | |
3441 | static ssize_t | |
3442 | tracing_read_pipe(struct file *filp, char __user *ubuf, | |
3443 | size_t cnt, loff_t *ppos) | |
3444 | { | |
3445 | struct trace_iterator *iter = filp->private_data; | |
d7350c3f | 3446 | static struct tracer *old_tracer; |
ff98781b EGM |
3447 | ssize_t sret; |
3448 | ||
3449 | /* return any leftover data */ | |
3450 | sret = trace_seq_to_user(&iter->seq, ubuf, cnt); | |
3451 | if (sret != -EBUSY) | |
3452 | return sret; | |
3453 | ||
f9520750 | 3454 | trace_seq_init(&iter->seq); |
ff98781b | 3455 | |
d7350c3f | 3456 | /* copy the tracer to avoid using a global lock all around */ |
ff98781b | 3457 | mutex_lock(&trace_types_lock); |
d7350c3f FW |
3458 | if (unlikely(old_tracer != current_trace && current_trace)) { |
3459 | old_tracer = current_trace; | |
3460 | *iter->trace = *current_trace; | |
3461 | } | |
3462 | mutex_unlock(&trace_types_lock); | |
3463 | ||
3464 | /* | |
3465 | * Avoid more than one consumer on a single file descriptor | |
3466 | * This is just a matter of traces coherency, the ring buffer itself | |
3467 | * is protected. | |
3468 | */ | |
3469 | mutex_lock(&iter->mutex); | |
ff98781b EGM |
3470 | if (iter->trace->read) { |
3471 | sret = iter->trace->read(iter, filp, ubuf, cnt, ppos); | |
3472 | if (sret) | |
3473 | goto out; | |
3474 | } | |
3475 | ||
3476 | waitagain: | |
3477 | sret = tracing_wait_pipe(filp); | |
3478 | if (sret <= 0) | |
3479 | goto out; | |
3480 | ||
b3806b43 | 3481 | /* stop when tracing is finished */ |
ff98781b EGM |
3482 | if (trace_empty(iter)) { |
3483 | sret = 0; | |
107bad8b | 3484 | goto out; |
ff98781b | 3485 | } |
b3806b43 SR |
3486 | |
3487 | if (cnt >= PAGE_SIZE) | |
3488 | cnt = PAGE_SIZE - 1; | |
3489 | ||
53d0aa77 | 3490 | /* reset all but tr, trace, and overruns */ |
53d0aa77 SR |
3491 | memset(&iter->seq, 0, |
3492 | sizeof(struct trace_iterator) - | |
3493 | offsetof(struct trace_iterator, seq)); | |
4823ed7e | 3494 | iter->pos = -1; |
b3806b43 | 3495 | |
4f535968 | 3496 | trace_event_read_lock(); |
7e53bd42 | 3497 | trace_access_lock(iter->cpu_file); |
955b61e5 | 3498 | while (trace_find_next_entry_inc(iter) != NULL) { |
2c4f035f | 3499 | enum print_line_t ret; |
088b1e42 SR |
3500 | int len = iter->seq.len; |
3501 | ||
f9896bf3 | 3502 | ret = print_trace_line(iter); |
2c4f035f | 3503 | if (ret == TRACE_TYPE_PARTIAL_LINE) { |
088b1e42 SR |
3504 | /* don't print partial lines */ |
3505 | iter->seq.len = len; | |
b3806b43 | 3506 | break; |
088b1e42 | 3507 | } |
b91facc3 FW |
3508 | if (ret != TRACE_TYPE_NO_CONSUME) |
3509 | trace_consume(iter); | |
b3806b43 SR |
3510 | |
3511 | if (iter->seq.len >= cnt) | |
3512 | break; | |
ee5e51f5 JO |
3513 | |
3514 | /* | |
3515 | * Setting the full flag means we reached the trace_seq buffer | |
3516 | * size and we should leave by partial output condition above. | |
3517 | * One of the trace_seq_* functions is not used properly. | |
3518 | */ | |
3519 | WARN_ONCE(iter->seq.full, "full flag set for trace type %d", | |
3520 | iter->ent->type); | |
b3806b43 | 3521 | } |
7e53bd42 | 3522 | trace_access_unlock(iter->cpu_file); |
4f535968 | 3523 | trace_event_read_unlock(); |
b3806b43 | 3524 | |
b3806b43 | 3525 | /* Now copy what we have to the user */ |
6c6c2796 PP |
3526 | sret = trace_seq_to_user(&iter->seq, ubuf, cnt); |
3527 | if (iter->seq.readpos >= iter->seq.len) | |
f9520750 | 3528 | trace_seq_init(&iter->seq); |
9ff4b974 PP |
3529 | |
3530 | /* | |
25985edc | 3531 | * If there was nothing to send to user, in spite of consuming trace |
9ff4b974 PP |
3532 | * entries, go back to wait for more entries. |
3533 | */ | |
6c6c2796 | 3534 | if (sret == -EBUSY) |
9ff4b974 | 3535 | goto waitagain; |
b3806b43 | 3536 | |
107bad8b | 3537 | out: |
d7350c3f | 3538 | mutex_unlock(&iter->mutex); |
107bad8b | 3539 | |
6c6c2796 | 3540 | return sret; |
b3806b43 SR |
3541 | } |
3542 | ||
3c56819b EGM |
3543 | static void tracing_pipe_buf_release(struct pipe_inode_info *pipe, |
3544 | struct pipe_buffer *buf) | |
3545 | { | |
3546 | __free_page(buf->page); | |
3547 | } | |
3548 | ||
3549 | static void tracing_spd_release_pipe(struct splice_pipe_desc *spd, | |
3550 | unsigned int idx) | |
3551 | { | |
3552 | __free_page(spd->pages[idx]); | |
3553 | } | |
3554 | ||
28dfef8f | 3555 | static const struct pipe_buf_operations tracing_pipe_buf_ops = { |
34cd4998 SR |
3556 | .can_merge = 0, |
3557 | .map = generic_pipe_buf_map, | |
3558 | .unmap = generic_pipe_buf_unmap, | |
3559 | .confirm = generic_pipe_buf_confirm, | |
3560 | .release = tracing_pipe_buf_release, | |
3561 | .steal = generic_pipe_buf_steal, | |
3562 | .get = generic_pipe_buf_get, | |
3c56819b EGM |
3563 | }; |
3564 | ||
34cd4998 | 3565 | static size_t |
fa7c7f6e | 3566 | tracing_fill_pipe_page(size_t rem, struct trace_iterator *iter) |
34cd4998 SR |
3567 | { |
3568 | size_t count; | |
3569 | int ret; | |
3570 | ||
3571 | /* Seq buffer is page-sized, exactly what we need. */ | |
3572 | for (;;) { | |
3573 | count = iter->seq.len; | |
3574 | ret = print_trace_line(iter); | |
3575 | count = iter->seq.len - count; | |
3576 | if (rem < count) { | |
3577 | rem = 0; | |
3578 | iter->seq.len -= count; | |
3579 | break; | |
3580 | } | |
3581 | if (ret == TRACE_TYPE_PARTIAL_LINE) { | |
3582 | iter->seq.len -= count; | |
3583 | break; | |
3584 | } | |
3585 | ||
74e7ff8c LJ |
3586 | if (ret != TRACE_TYPE_NO_CONSUME) |
3587 | trace_consume(iter); | |
34cd4998 | 3588 | rem -= count; |
955b61e5 | 3589 | if (!trace_find_next_entry_inc(iter)) { |
34cd4998 SR |
3590 | rem = 0; |
3591 | iter->ent = NULL; | |
3592 | break; | |
3593 | } | |
3594 | } | |
3595 | ||
3596 | return rem; | |
3597 | } | |
3598 | ||
3c56819b EGM |
3599 | static ssize_t tracing_splice_read_pipe(struct file *filp, |
3600 | loff_t *ppos, | |
3601 | struct pipe_inode_info *pipe, | |
3602 | size_t len, | |
3603 | unsigned int flags) | |
3604 | { | |
35f3d14d JA |
3605 | struct page *pages_def[PIPE_DEF_BUFFERS]; |
3606 | struct partial_page partial_def[PIPE_DEF_BUFFERS]; | |
3c56819b EGM |
3607 | struct trace_iterator *iter = filp->private_data; |
3608 | struct splice_pipe_desc spd = { | |
35f3d14d JA |
3609 | .pages = pages_def, |
3610 | .partial = partial_def, | |
34cd4998 SR |
3611 | .nr_pages = 0, /* This gets updated below. */ |
3612 | .flags = flags, | |
3613 | .ops = &tracing_pipe_buf_ops, | |
3614 | .spd_release = tracing_spd_release_pipe, | |
3c56819b | 3615 | }; |
d7350c3f | 3616 | static struct tracer *old_tracer; |
3c56819b | 3617 | ssize_t ret; |
34cd4998 | 3618 | size_t rem; |
3c56819b EGM |
3619 | unsigned int i; |
3620 | ||
35f3d14d JA |
3621 | if (splice_grow_spd(pipe, &spd)) |
3622 | return -ENOMEM; | |
3623 | ||
d7350c3f | 3624 | /* copy the tracer to avoid using a global lock all around */ |
3c56819b | 3625 | mutex_lock(&trace_types_lock); |
d7350c3f FW |
3626 | if (unlikely(old_tracer != current_trace && current_trace)) { |
3627 | old_tracer = current_trace; | |
3628 | *iter->trace = *current_trace; | |
3629 | } | |
3630 | mutex_unlock(&trace_types_lock); | |
3631 | ||
3632 | mutex_lock(&iter->mutex); | |
3c56819b EGM |
3633 | |
3634 | if (iter->trace->splice_read) { | |
3635 | ret = iter->trace->splice_read(iter, filp, | |
3636 | ppos, pipe, len, flags); | |
3637 | if (ret) | |
34cd4998 | 3638 | goto out_err; |
3c56819b EGM |
3639 | } |
3640 | ||
3641 | ret = tracing_wait_pipe(filp); | |
3642 | if (ret <= 0) | |
34cd4998 | 3643 | goto out_err; |
3c56819b | 3644 | |
955b61e5 | 3645 | if (!iter->ent && !trace_find_next_entry_inc(iter)) { |
3c56819b | 3646 | ret = -EFAULT; |
34cd4998 | 3647 | goto out_err; |
3c56819b EGM |
3648 | } |
3649 | ||
4f535968 | 3650 | trace_event_read_lock(); |
7e53bd42 | 3651 | trace_access_lock(iter->cpu_file); |
4f535968 | 3652 | |
3c56819b | 3653 | /* Fill as many pages as possible. */ |
35f3d14d JA |
3654 | for (i = 0, rem = len; i < pipe->buffers && rem; i++) { |
3655 | spd.pages[i] = alloc_page(GFP_KERNEL); | |
3656 | if (!spd.pages[i]) | |
34cd4998 | 3657 | break; |
3c56819b | 3658 | |
fa7c7f6e | 3659 | rem = tracing_fill_pipe_page(rem, iter); |
3c56819b EGM |
3660 | |
3661 | /* Copy the data into the page, so we can start over. */ | |
3662 | ret = trace_seq_to_buffer(&iter->seq, | |
35f3d14d | 3663 | page_address(spd.pages[i]), |
3c56819b EGM |
3664 | iter->seq.len); |
3665 | if (ret < 0) { | |
35f3d14d | 3666 | __free_page(spd.pages[i]); |
3c56819b EGM |
3667 | break; |
3668 | } | |
35f3d14d JA |
3669 | spd.partial[i].offset = 0; |
3670 | spd.partial[i].len = iter->seq.len; | |
3c56819b | 3671 | |
f9520750 | 3672 | trace_seq_init(&iter->seq); |
3c56819b EGM |
3673 | } |
3674 | ||
7e53bd42 | 3675 | trace_access_unlock(iter->cpu_file); |
4f535968 | 3676 | trace_event_read_unlock(); |
d7350c3f | 3677 | mutex_unlock(&iter->mutex); |
3c56819b EGM |
3678 | |
3679 | spd.nr_pages = i; | |
3680 | ||
35f3d14d JA |
3681 | ret = splice_to_pipe(pipe, &spd); |
3682 | out: | |
3683 | splice_shrink_spd(pipe, &spd); | |
3684 | return ret; | |
3c56819b | 3685 | |
34cd4998 | 3686 | out_err: |
d7350c3f | 3687 | mutex_unlock(&iter->mutex); |
35f3d14d | 3688 | goto out; |
3c56819b EGM |
3689 | } |
3690 | ||
438ced17 VN |
3691 | struct ftrace_entries_info { |
3692 | struct trace_array *tr; | |
3693 | int cpu; | |
3694 | }; | |
3695 | ||
3696 | static int tracing_entries_open(struct inode *inode, struct file *filp) | |
3697 | { | |
3698 | struct ftrace_entries_info *info; | |
3699 | ||
3700 | if (tracing_disabled) | |
3701 | return -ENODEV; | |
3702 | ||
3703 | info = kzalloc(sizeof(*info), GFP_KERNEL); | |
3704 | if (!info) | |
3705 | return -ENOMEM; | |
3706 | ||
3707 | info->tr = &global_trace; | |
3708 | info->cpu = (unsigned long)inode->i_private; | |
3709 | ||
3710 | filp->private_data = info; | |
3711 | ||
3712 | return 0; | |
3713 | } | |
3714 | ||
a98a3c3f SR |
3715 | static ssize_t |
3716 | tracing_entries_read(struct file *filp, char __user *ubuf, | |
3717 | size_t cnt, loff_t *ppos) | |
3718 | { | |
438ced17 VN |
3719 | struct ftrace_entries_info *info = filp->private_data; |
3720 | struct trace_array *tr = info->tr; | |
3721 | char buf[64]; | |
3722 | int r = 0; | |
3723 | ssize_t ret; | |
a98a3c3f | 3724 | |
db526ca3 | 3725 | mutex_lock(&trace_types_lock); |
438ced17 VN |
3726 | |
3727 | if (info->cpu == RING_BUFFER_ALL_CPUS) { | |
3728 | int cpu, buf_size_same; | |
3729 | unsigned long size; | |
3730 | ||
3731 | size = 0; | |
3732 | buf_size_same = 1; | |
3733 | /* check if all cpu sizes are same */ | |
3734 | for_each_tracing_cpu(cpu) { | |
3735 | /* fill in the size from first enabled cpu */ | |
3736 | if (size == 0) | |
3737 | size = tr->data[cpu]->entries; | |
3738 | if (size != tr->data[cpu]->entries) { | |
3739 | buf_size_same = 0; | |
3740 | break; | |
3741 | } | |
3742 | } | |
3743 | ||
3744 | if (buf_size_same) { | |
3745 | if (!ring_buffer_expanded) | |
3746 | r = sprintf(buf, "%lu (expanded: %lu)\n", | |
3747 | size >> 10, | |
3748 | trace_buf_size >> 10); | |
3749 | else | |
3750 | r = sprintf(buf, "%lu\n", size >> 10); | |
3751 | } else | |
3752 | r = sprintf(buf, "X\n"); | |
3753 | } else | |
3754 | r = sprintf(buf, "%lu\n", tr->data[info->cpu]->entries >> 10); | |
3755 | ||
db526ca3 SR |
3756 | mutex_unlock(&trace_types_lock); |
3757 | ||
438ced17 VN |
3758 | ret = simple_read_from_buffer(ubuf, cnt, ppos, buf, r); |
3759 | return ret; | |
a98a3c3f SR |
3760 | } |
3761 | ||
3762 | static ssize_t | |
3763 | tracing_entries_write(struct file *filp, const char __user *ubuf, | |
3764 | size_t cnt, loff_t *ppos) | |
3765 | { | |
438ced17 | 3766 | struct ftrace_entries_info *info = filp->private_data; |
a98a3c3f | 3767 | unsigned long val; |
4f271a2a | 3768 | int ret; |
a98a3c3f | 3769 | |
22fe9b54 PH |
3770 | ret = kstrtoul_from_user(ubuf, cnt, 10, &val); |
3771 | if (ret) | |
c6caeeb1 | 3772 | return ret; |
a98a3c3f SR |
3773 | |
3774 | /* must have at least 1 entry */ | |
3775 | if (!val) | |
3776 | return -EINVAL; | |
3777 | ||
1696b2b0 SR |
3778 | /* value is in KB */ |
3779 | val <<= 10; | |
3780 | ||
438ced17 | 3781 | ret = tracing_resize_ring_buffer(val, info->cpu); |
4f271a2a VN |
3782 | if (ret < 0) |
3783 | return ret; | |
a98a3c3f | 3784 | |
cf8517cf | 3785 | *ppos += cnt; |
a98a3c3f | 3786 | |
4f271a2a VN |
3787 | return cnt; |
3788 | } | |
bf5e6519 | 3789 | |
438ced17 VN |
3790 | static int |
3791 | tracing_entries_release(struct inode *inode, struct file *filp) | |
3792 | { | |
3793 | struct ftrace_entries_info *info = filp->private_data; | |
3794 | ||
3795 | kfree(info); | |
3796 | ||
3797 | return 0; | |
3798 | } | |
3799 | ||
f81ab074 VN |
3800 | static ssize_t |
3801 | tracing_total_entries_read(struct file *filp, char __user *ubuf, | |
3802 | size_t cnt, loff_t *ppos) | |
3803 | { | |
3804 | struct trace_array *tr = filp->private_data; | |
3805 | char buf[64]; | |
3806 | int r, cpu; | |
3807 | unsigned long size = 0, expanded_size = 0; | |
3808 | ||
3809 | mutex_lock(&trace_types_lock); | |
3810 | for_each_tracing_cpu(cpu) { | |
438ced17 | 3811 | size += tr->data[cpu]->entries >> 10; |
f81ab074 VN |
3812 | if (!ring_buffer_expanded) |
3813 | expanded_size += trace_buf_size >> 10; | |
3814 | } | |
3815 | if (ring_buffer_expanded) | |
3816 | r = sprintf(buf, "%lu\n", size); | |
3817 | else | |
3818 | r = sprintf(buf, "%lu (expanded: %lu)\n", size, expanded_size); | |
3819 | mutex_unlock(&trace_types_lock); | |
3820 | ||
3821 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, r); | |
3822 | } | |
3823 | ||
4f271a2a VN |
3824 | static ssize_t |
3825 | tracing_free_buffer_write(struct file *filp, const char __user *ubuf, | |
3826 | size_t cnt, loff_t *ppos) | |
3827 | { | |
3828 | /* | |
3829 | * There is no need to read what the user has written, this function | |
3830 | * is just to make sure that there is no error when "echo" is used | |
3831 | */ | |
3832 | ||
3833 | *ppos += cnt; | |
a98a3c3f SR |
3834 | |
3835 | return cnt; | |
3836 | } | |
3837 | ||
4f271a2a VN |
3838 | static int |
3839 | tracing_free_buffer_release(struct inode *inode, struct file *filp) | |
3840 | { | |
cf30cf67 SR |
3841 | /* disable tracing ? */ |
3842 | if (trace_flags & TRACE_ITER_STOP_ON_FREE) | |
3843 | tracing_off(); | |
4f271a2a | 3844 | /* resize the ring buffer to 0 */ |
438ced17 | 3845 | tracing_resize_ring_buffer(0, RING_BUFFER_ALL_CPUS); |
4f271a2a VN |
3846 | |
3847 | return 0; | |
3848 | } | |
3849 | ||
5bf9a1ee PP |
3850 | static ssize_t |
3851 | tracing_mark_write(struct file *filp, const char __user *ubuf, | |
3852 | size_t cnt, loff_t *fpos) | |
3853 | { | |
d696b58c SR |
3854 | unsigned long addr = (unsigned long)ubuf; |
3855 | struct ring_buffer_event *event; | |
3856 | struct ring_buffer *buffer; | |
3857 | struct print_entry *entry; | |
3858 | unsigned long irq_flags; | |
3859 | struct page *pages[2]; | |
6edb2a8a | 3860 | void *map_page[2]; |
d696b58c SR |
3861 | int nr_pages = 1; |
3862 | ssize_t written; | |
d696b58c SR |
3863 | int offset; |
3864 | int size; | |
3865 | int len; | |
3866 | int ret; | |
6edb2a8a | 3867 | int i; |
5bf9a1ee | 3868 | |
c76f0694 | 3869 | if (tracing_disabled) |
5bf9a1ee PP |
3870 | return -EINVAL; |
3871 | ||
3872 | if (cnt > TRACE_BUF_SIZE) | |
3873 | cnt = TRACE_BUF_SIZE; | |
3874 | ||
d696b58c SR |
3875 | /* |
3876 | * Userspace is injecting traces into the kernel trace buffer. | |
3877 | * We want to be as non intrusive as possible. | |
3878 | * To do so, we do not want to allocate any special buffers | |
3879 | * or take any locks, but instead write the userspace data | |
3880 | * straight into the ring buffer. | |
3881 | * | |
3882 | * First we need to pin the userspace buffer into memory, | |
3883 | * which, most likely it is, because it just referenced it. | |
3884 | * But there's no guarantee that it is. By using get_user_pages_fast() | |
3885 | * and kmap_atomic/kunmap_atomic() we can get access to the | |
3886 | * pages directly. We then write the data directly into the | |
3887 | * ring buffer. | |
3888 | */ | |
3889 | BUILD_BUG_ON(TRACE_BUF_SIZE >= PAGE_SIZE); | |
5bf9a1ee | 3890 | |
d696b58c SR |
3891 | /* check if we cross pages */ |
3892 | if ((addr & PAGE_MASK) != ((addr + cnt) & PAGE_MASK)) | |
3893 | nr_pages = 2; | |
3894 | ||
3895 | offset = addr & (PAGE_SIZE - 1); | |
3896 | addr &= PAGE_MASK; | |
3897 | ||
3898 | ret = get_user_pages_fast(addr, nr_pages, 0, pages); | |
3899 | if (ret < nr_pages) { | |
3900 | while (--ret >= 0) | |
3901 | put_page(pages[ret]); | |
3902 | written = -EFAULT; | |
3903 | goto out; | |
5bf9a1ee | 3904 | } |
d696b58c | 3905 | |
6edb2a8a SR |
3906 | for (i = 0; i < nr_pages; i++) |
3907 | map_page[i] = kmap_atomic(pages[i]); | |
d696b58c SR |
3908 | |
3909 | local_save_flags(irq_flags); | |
3910 | size = sizeof(*entry) + cnt + 2; /* possible \n added */ | |
3911 | buffer = global_trace.buffer; | |
3912 | event = trace_buffer_lock_reserve(buffer, TRACE_PRINT, size, | |
3913 | irq_flags, preempt_count()); | |
3914 | if (!event) { | |
3915 | /* Ring buffer disabled, return as if not open for write */ | |
3916 | written = -EBADF; | |
3917 | goto out_unlock; | |
5bf9a1ee | 3918 | } |
d696b58c SR |
3919 | |
3920 | entry = ring_buffer_event_data(event); | |
3921 | entry->ip = _THIS_IP_; | |
3922 | ||
3923 | if (nr_pages == 2) { | |
3924 | len = PAGE_SIZE - offset; | |
6edb2a8a SR |
3925 | memcpy(&entry->buf, map_page[0] + offset, len); |
3926 | memcpy(&entry->buf[len], map_page[1], cnt - len); | |
c13d2f7c | 3927 | } else |
6edb2a8a | 3928 | memcpy(&entry->buf, map_page[0] + offset, cnt); |
5bf9a1ee | 3929 | |
d696b58c SR |
3930 | if (entry->buf[cnt - 1] != '\n') { |
3931 | entry->buf[cnt] = '\n'; | |
3932 | entry->buf[cnt + 1] = '\0'; | |
3933 | } else | |
3934 | entry->buf[cnt] = '\0'; | |
3935 | ||
3936 | ring_buffer_unlock_commit(buffer, event); | |
5bf9a1ee | 3937 | |
d696b58c | 3938 | written = cnt; |
5bf9a1ee | 3939 | |
d696b58c | 3940 | *fpos += written; |
1aa54bca | 3941 | |
d696b58c | 3942 | out_unlock: |
6edb2a8a SR |
3943 | for (i = 0; i < nr_pages; i++){ |
3944 | kunmap_atomic(map_page[i]); | |
3945 | put_page(pages[i]); | |
3946 | } | |
d696b58c | 3947 | out: |
1aa54bca | 3948 | return written; |
5bf9a1ee PP |
3949 | } |
3950 | ||
13f16d20 | 3951 | static int tracing_clock_show(struct seq_file *m, void *v) |
5079f326 | 3952 | { |
5079f326 Z |
3953 | int i; |
3954 | ||
3955 | for (i = 0; i < ARRAY_SIZE(trace_clocks); i++) | |
13f16d20 | 3956 | seq_printf(m, |
5079f326 Z |
3957 | "%s%s%s%s", i ? " " : "", |
3958 | i == trace_clock_id ? "[" : "", trace_clocks[i].name, | |
3959 | i == trace_clock_id ? "]" : ""); | |
13f16d20 | 3960 | seq_putc(m, '\n'); |
5079f326 | 3961 | |
13f16d20 | 3962 | return 0; |
5079f326 Z |
3963 | } |
3964 | ||
3965 | static ssize_t tracing_clock_write(struct file *filp, const char __user *ubuf, | |
3966 | size_t cnt, loff_t *fpos) | |
3967 | { | |
3968 | char buf[64]; | |
3969 | const char *clockstr; | |
3970 | int i; | |
3971 | ||
3972 | if (cnt >= sizeof(buf)) | |
3973 | return -EINVAL; | |
3974 | ||
3975 | if (copy_from_user(&buf, ubuf, cnt)) | |
3976 | return -EFAULT; | |
3977 | ||
3978 | buf[cnt] = 0; | |
3979 | ||
3980 | clockstr = strstrip(buf); | |
3981 | ||
3982 | for (i = 0; i < ARRAY_SIZE(trace_clocks); i++) { | |
3983 | if (strcmp(trace_clocks[i].name, clockstr) == 0) | |
3984 | break; | |
3985 | } | |
3986 | if (i == ARRAY_SIZE(trace_clocks)) | |
3987 | return -EINVAL; | |
3988 | ||
3989 | trace_clock_id = i; | |
3990 | ||
3991 | mutex_lock(&trace_types_lock); | |
3992 | ||
3993 | ring_buffer_set_clock(global_trace.buffer, trace_clocks[i].func); | |
3994 | if (max_tr.buffer) | |
3995 | ring_buffer_set_clock(max_tr.buffer, trace_clocks[i].func); | |
3996 | ||
3997 | mutex_unlock(&trace_types_lock); | |
3998 | ||
3999 | *fpos += cnt; | |
4000 | ||
4001 | return cnt; | |
4002 | } | |
4003 | ||
13f16d20 LZ |
4004 | static int tracing_clock_open(struct inode *inode, struct file *file) |
4005 | { | |
4006 | if (tracing_disabled) | |
4007 | return -ENODEV; | |
4008 | return single_open(file, tracing_clock_show, NULL); | |
4009 | } | |
4010 | ||
5e2336a0 | 4011 | static const struct file_operations tracing_max_lat_fops = { |
4bf39a94 IM |
4012 | .open = tracing_open_generic, |
4013 | .read = tracing_max_lat_read, | |
4014 | .write = tracing_max_lat_write, | |
b444786f | 4015 | .llseek = generic_file_llseek, |
bc0c38d1 SR |
4016 | }; |
4017 | ||
5e2336a0 | 4018 | static const struct file_operations tracing_ctrl_fops = { |
4bf39a94 IM |
4019 | .open = tracing_open_generic, |
4020 | .read = tracing_ctrl_read, | |
4021 | .write = tracing_ctrl_write, | |
b444786f | 4022 | .llseek = generic_file_llseek, |
bc0c38d1 SR |
4023 | }; |
4024 | ||
5e2336a0 | 4025 | static const struct file_operations set_tracer_fops = { |
4bf39a94 IM |
4026 | .open = tracing_open_generic, |
4027 | .read = tracing_set_trace_read, | |
4028 | .write = tracing_set_trace_write, | |
b444786f | 4029 | .llseek = generic_file_llseek, |
bc0c38d1 SR |
4030 | }; |
4031 | ||
5e2336a0 | 4032 | static const struct file_operations tracing_pipe_fops = { |
4bf39a94 | 4033 | .open = tracing_open_pipe, |
2a2cc8f7 | 4034 | .poll = tracing_poll_pipe, |
4bf39a94 | 4035 | .read = tracing_read_pipe, |
3c56819b | 4036 | .splice_read = tracing_splice_read_pipe, |
4bf39a94 | 4037 | .release = tracing_release_pipe, |
b444786f | 4038 | .llseek = no_llseek, |
b3806b43 SR |
4039 | }; |
4040 | ||
5e2336a0 | 4041 | static const struct file_operations tracing_entries_fops = { |
438ced17 | 4042 | .open = tracing_entries_open, |
a98a3c3f SR |
4043 | .read = tracing_entries_read, |
4044 | .write = tracing_entries_write, | |
438ced17 | 4045 | .release = tracing_entries_release, |
b444786f | 4046 | .llseek = generic_file_llseek, |
a98a3c3f SR |
4047 | }; |
4048 | ||
f81ab074 VN |
4049 | static const struct file_operations tracing_total_entries_fops = { |
4050 | .open = tracing_open_generic, | |
4051 | .read = tracing_total_entries_read, | |
4052 | .llseek = generic_file_llseek, | |
4053 | }; | |
4054 | ||
4f271a2a VN |
4055 | static const struct file_operations tracing_free_buffer_fops = { |
4056 | .write = tracing_free_buffer_write, | |
4057 | .release = tracing_free_buffer_release, | |
4058 | }; | |
4059 | ||
5e2336a0 | 4060 | static const struct file_operations tracing_mark_fops = { |
43a15386 | 4061 | .open = tracing_open_generic, |
5bf9a1ee | 4062 | .write = tracing_mark_write, |
b444786f | 4063 | .llseek = generic_file_llseek, |
5bf9a1ee PP |
4064 | }; |
4065 | ||
5079f326 | 4066 | static const struct file_operations trace_clock_fops = { |
13f16d20 LZ |
4067 | .open = tracing_clock_open, |
4068 | .read = seq_read, | |
4069 | .llseek = seq_lseek, | |
4070 | .release = single_release, | |
5079f326 Z |
4071 | .write = tracing_clock_write, |
4072 | }; | |
4073 | ||
2cadf913 SR |
4074 | struct ftrace_buffer_info { |
4075 | struct trace_array *tr; | |
4076 | void *spare; | |
4077 | int cpu; | |
4078 | unsigned int read; | |
4079 | }; | |
4080 | ||
4081 | static int tracing_buffers_open(struct inode *inode, struct file *filp) | |
4082 | { | |
4083 | int cpu = (int)(long)inode->i_private; | |
4084 | struct ftrace_buffer_info *info; | |
4085 | ||
4086 | if (tracing_disabled) | |
4087 | return -ENODEV; | |
4088 | ||
4089 | info = kzalloc(sizeof(*info), GFP_KERNEL); | |
4090 | if (!info) | |
4091 | return -ENOMEM; | |
4092 | ||
4093 | info->tr = &global_trace; | |
4094 | info->cpu = cpu; | |
ddd538f3 | 4095 | info->spare = NULL; |
2cadf913 SR |
4096 | /* Force reading ring buffer for first read */ |
4097 | info->read = (unsigned int)-1; | |
2cadf913 SR |
4098 | |
4099 | filp->private_data = info; | |
4100 | ||
d1e7e02f | 4101 | return nonseekable_open(inode, filp); |
2cadf913 SR |
4102 | } |
4103 | ||
4104 | static ssize_t | |
4105 | tracing_buffers_read(struct file *filp, char __user *ubuf, | |
4106 | size_t count, loff_t *ppos) | |
4107 | { | |
4108 | struct ftrace_buffer_info *info = filp->private_data; | |
2cadf913 SR |
4109 | ssize_t ret; |
4110 | size_t size; | |
4111 | ||
2dc5d12b SR |
4112 | if (!count) |
4113 | return 0; | |
4114 | ||
ddd538f3 | 4115 | if (!info->spare) |
7ea59064 | 4116 | info->spare = ring_buffer_alloc_read_page(info->tr->buffer, info->cpu); |
ddd538f3 LJ |
4117 | if (!info->spare) |
4118 | return -ENOMEM; | |
4119 | ||
2cadf913 SR |
4120 | /* Do we have previous read data to read? */ |
4121 | if (info->read < PAGE_SIZE) | |
4122 | goto read; | |
4123 | ||
7e53bd42 | 4124 | trace_access_lock(info->cpu); |
2cadf913 SR |
4125 | ret = ring_buffer_read_page(info->tr->buffer, |
4126 | &info->spare, | |
4127 | count, | |
4128 | info->cpu, 0); | |
7e53bd42 | 4129 | trace_access_unlock(info->cpu); |
2cadf913 SR |
4130 | if (ret < 0) |
4131 | return 0; | |
4132 | ||
436fc280 SR |
4133 | info->read = 0; |
4134 | ||
2cadf913 SR |
4135 | read: |
4136 | size = PAGE_SIZE - info->read; | |
4137 | if (size > count) | |
4138 | size = count; | |
4139 | ||
4140 | ret = copy_to_user(ubuf, info->spare + info->read, size); | |
2dc5d12b | 4141 | if (ret == size) |
2cadf913 | 4142 | return -EFAULT; |
2dc5d12b SR |
4143 | size -= ret; |
4144 | ||
2cadf913 SR |
4145 | *ppos += size; |
4146 | info->read += size; | |
4147 | ||
4148 | return size; | |
4149 | } | |
4150 | ||
4151 | static int tracing_buffers_release(struct inode *inode, struct file *file) | |
4152 | { | |
4153 | struct ftrace_buffer_info *info = file->private_data; | |
4154 | ||
ddd538f3 LJ |
4155 | if (info->spare) |
4156 | ring_buffer_free_read_page(info->tr->buffer, info->spare); | |
2cadf913 SR |
4157 | kfree(info); |
4158 | ||
4159 | return 0; | |
4160 | } | |
4161 | ||
4162 | struct buffer_ref { | |
4163 | struct ring_buffer *buffer; | |
4164 | void *page; | |
4165 | int ref; | |
4166 | }; | |
4167 | ||
4168 | static void buffer_pipe_buf_release(struct pipe_inode_info *pipe, | |
4169 | struct pipe_buffer *buf) | |
4170 | { | |
4171 | struct buffer_ref *ref = (struct buffer_ref *)buf->private; | |
4172 | ||
4173 | if (--ref->ref) | |
4174 | return; | |
4175 | ||
4176 | ring_buffer_free_read_page(ref->buffer, ref->page); | |
4177 | kfree(ref); | |
4178 | buf->private = 0; | |
4179 | } | |
4180 | ||
4181 | static int buffer_pipe_buf_steal(struct pipe_inode_info *pipe, | |
4182 | struct pipe_buffer *buf) | |
4183 | { | |
4184 | return 1; | |
4185 | } | |
4186 | ||
4187 | static void buffer_pipe_buf_get(struct pipe_inode_info *pipe, | |
4188 | struct pipe_buffer *buf) | |
4189 | { | |
4190 | struct buffer_ref *ref = (struct buffer_ref *)buf->private; | |
4191 | ||
4192 | ref->ref++; | |
4193 | } | |
4194 | ||
4195 | /* Pipe buffer operations for a buffer. */ | |
28dfef8f | 4196 | static const struct pipe_buf_operations buffer_pipe_buf_ops = { |
2cadf913 SR |
4197 | .can_merge = 0, |
4198 | .map = generic_pipe_buf_map, | |
4199 | .unmap = generic_pipe_buf_unmap, | |
4200 | .confirm = generic_pipe_buf_confirm, | |
4201 | .release = buffer_pipe_buf_release, | |
4202 | .steal = buffer_pipe_buf_steal, | |
4203 | .get = buffer_pipe_buf_get, | |
4204 | }; | |
4205 | ||
4206 | /* | |
4207 | * Callback from splice_to_pipe(), if we need to release some pages | |
4208 | * at the end of the spd in case we error'ed out in filling the pipe. | |
4209 | */ | |
4210 | static void buffer_spd_release(struct splice_pipe_desc *spd, unsigned int i) | |
4211 | { | |
4212 | struct buffer_ref *ref = | |
4213 | (struct buffer_ref *)spd->partial[i].private; | |
4214 | ||
4215 | if (--ref->ref) | |
4216 | return; | |
4217 | ||
4218 | ring_buffer_free_read_page(ref->buffer, ref->page); | |
4219 | kfree(ref); | |
4220 | spd->partial[i].private = 0; | |
4221 | } | |
4222 | ||
4223 | static ssize_t | |
4224 | tracing_buffers_splice_read(struct file *file, loff_t *ppos, | |
4225 | struct pipe_inode_info *pipe, size_t len, | |
4226 | unsigned int flags) | |
4227 | { | |
4228 | struct ftrace_buffer_info *info = file->private_data; | |
35f3d14d JA |
4229 | struct partial_page partial_def[PIPE_DEF_BUFFERS]; |
4230 | struct page *pages_def[PIPE_DEF_BUFFERS]; | |
2cadf913 | 4231 | struct splice_pipe_desc spd = { |
35f3d14d JA |
4232 | .pages = pages_def, |
4233 | .partial = partial_def, | |
2cadf913 SR |
4234 | .flags = flags, |
4235 | .ops = &buffer_pipe_buf_ops, | |
4236 | .spd_release = buffer_spd_release, | |
4237 | }; | |
4238 | struct buffer_ref *ref; | |
93459c6c | 4239 | int entries, size, i; |
2cadf913 SR |
4240 | size_t ret; |
4241 | ||
35f3d14d JA |
4242 | if (splice_grow_spd(pipe, &spd)) |
4243 | return -ENOMEM; | |
4244 | ||
93cfb3c9 LJ |
4245 | if (*ppos & (PAGE_SIZE - 1)) { |
4246 | WARN_ONCE(1, "Ftrace: previous read must page-align\n"); | |
35f3d14d JA |
4247 | ret = -EINVAL; |
4248 | goto out; | |
93cfb3c9 LJ |
4249 | } |
4250 | ||
4251 | if (len & (PAGE_SIZE - 1)) { | |
4252 | WARN_ONCE(1, "Ftrace: splice_read should page-align\n"); | |
35f3d14d JA |
4253 | if (len < PAGE_SIZE) { |
4254 | ret = -EINVAL; | |
4255 | goto out; | |
4256 | } | |
93cfb3c9 LJ |
4257 | len &= PAGE_MASK; |
4258 | } | |
4259 | ||
7e53bd42 | 4260 | trace_access_lock(info->cpu); |
93459c6c SR |
4261 | entries = ring_buffer_entries_cpu(info->tr->buffer, info->cpu); |
4262 | ||
35f3d14d | 4263 | for (i = 0; i < pipe->buffers && len && entries; i++, len -= PAGE_SIZE) { |
2cadf913 SR |
4264 | struct page *page; |
4265 | int r; | |
4266 | ||
4267 | ref = kzalloc(sizeof(*ref), GFP_KERNEL); | |
4268 | if (!ref) | |
4269 | break; | |
4270 | ||
7267fa68 | 4271 | ref->ref = 1; |
2cadf913 | 4272 | ref->buffer = info->tr->buffer; |
7ea59064 | 4273 | ref->page = ring_buffer_alloc_read_page(ref->buffer, info->cpu); |
2cadf913 SR |
4274 | if (!ref->page) { |
4275 | kfree(ref); | |
4276 | break; | |
4277 | } | |
4278 | ||
4279 | r = ring_buffer_read_page(ref->buffer, &ref->page, | |
f2957f1f | 4280 | len, info->cpu, 1); |
2cadf913 | 4281 | if (r < 0) { |
7ea59064 | 4282 | ring_buffer_free_read_page(ref->buffer, ref->page); |
2cadf913 SR |
4283 | kfree(ref); |
4284 | break; | |
4285 | } | |
4286 | ||
4287 | /* | |
4288 | * zero out any left over data, this is going to | |
4289 | * user land. | |
4290 | */ | |
4291 | size = ring_buffer_page_len(ref->page); | |
4292 | if (size < PAGE_SIZE) | |
4293 | memset(ref->page + size, 0, PAGE_SIZE - size); | |
4294 | ||
4295 | page = virt_to_page(ref->page); | |
4296 | ||
4297 | spd.pages[i] = page; | |
4298 | spd.partial[i].len = PAGE_SIZE; | |
4299 | spd.partial[i].offset = 0; | |
4300 | spd.partial[i].private = (unsigned long)ref; | |
4301 | spd.nr_pages++; | |
93cfb3c9 | 4302 | *ppos += PAGE_SIZE; |
93459c6c SR |
4303 | |
4304 | entries = ring_buffer_entries_cpu(info->tr->buffer, info->cpu); | |
2cadf913 SR |
4305 | } |
4306 | ||
7e53bd42 | 4307 | trace_access_unlock(info->cpu); |
2cadf913 SR |
4308 | spd.nr_pages = i; |
4309 | ||
4310 | /* did we read anything? */ | |
4311 | if (!spd.nr_pages) { | |
4312 | if (flags & SPLICE_F_NONBLOCK) | |
4313 | ret = -EAGAIN; | |
4314 | else | |
4315 | ret = 0; | |
4316 | /* TODO: block */ | |
35f3d14d | 4317 | goto out; |
2cadf913 SR |
4318 | } |
4319 | ||
4320 | ret = splice_to_pipe(pipe, &spd); | |
35f3d14d JA |
4321 | splice_shrink_spd(pipe, &spd); |
4322 | out: | |
2cadf913 SR |
4323 | return ret; |
4324 | } | |
4325 | ||
4326 | static const struct file_operations tracing_buffers_fops = { | |
4327 | .open = tracing_buffers_open, | |
4328 | .read = tracing_buffers_read, | |
4329 | .release = tracing_buffers_release, | |
4330 | .splice_read = tracing_buffers_splice_read, | |
4331 | .llseek = no_llseek, | |
4332 | }; | |
4333 | ||
c8d77183 SR |
4334 | static ssize_t |
4335 | tracing_stats_read(struct file *filp, char __user *ubuf, | |
4336 | size_t count, loff_t *ppos) | |
4337 | { | |
4338 | unsigned long cpu = (unsigned long)filp->private_data; | |
4339 | struct trace_array *tr = &global_trace; | |
4340 | struct trace_seq *s; | |
4341 | unsigned long cnt; | |
c64e148a VN |
4342 | unsigned long long t; |
4343 | unsigned long usec_rem; | |
c8d77183 | 4344 | |
e4f2d10f | 4345 | s = kmalloc(sizeof(*s), GFP_KERNEL); |
c8d77183 | 4346 | if (!s) |
a646365c | 4347 | return -ENOMEM; |
c8d77183 SR |
4348 | |
4349 | trace_seq_init(s); | |
4350 | ||
4351 | cnt = ring_buffer_entries_cpu(tr->buffer, cpu); | |
4352 | trace_seq_printf(s, "entries: %ld\n", cnt); | |
4353 | ||
4354 | cnt = ring_buffer_overrun_cpu(tr->buffer, cpu); | |
4355 | trace_seq_printf(s, "overrun: %ld\n", cnt); | |
4356 | ||
4357 | cnt = ring_buffer_commit_overrun_cpu(tr->buffer, cpu); | |
4358 | trace_seq_printf(s, "commit overrun: %ld\n", cnt); | |
4359 | ||
c64e148a VN |
4360 | cnt = ring_buffer_bytes_cpu(tr->buffer, cpu); |
4361 | trace_seq_printf(s, "bytes: %ld\n", cnt); | |
4362 | ||
4363 | t = ns2usecs(ring_buffer_oldest_event_ts(tr->buffer, cpu)); | |
4364 | usec_rem = do_div(t, USEC_PER_SEC); | |
4365 | trace_seq_printf(s, "oldest event ts: %5llu.%06lu\n", t, usec_rem); | |
4366 | ||
4367 | t = ns2usecs(ring_buffer_time_stamp(tr->buffer, cpu)); | |
4368 | usec_rem = do_div(t, USEC_PER_SEC); | |
4369 | trace_seq_printf(s, "now ts: %5llu.%06lu\n", t, usec_rem); | |
4370 | ||
c8d77183 SR |
4371 | count = simple_read_from_buffer(ubuf, count, ppos, s->buffer, s->len); |
4372 | ||
4373 | kfree(s); | |
4374 | ||
4375 | return count; | |
4376 | } | |
4377 | ||
4378 | static const struct file_operations tracing_stats_fops = { | |
4379 | .open = tracing_open_generic, | |
4380 | .read = tracing_stats_read, | |
b444786f | 4381 | .llseek = generic_file_llseek, |
c8d77183 SR |
4382 | }; |
4383 | ||
bc0c38d1 SR |
4384 | #ifdef CONFIG_DYNAMIC_FTRACE |
4385 | ||
b807c3d0 SR |
4386 | int __weak ftrace_arch_read_dyn_info(char *buf, int size) |
4387 | { | |
4388 | return 0; | |
4389 | } | |
4390 | ||
bc0c38d1 | 4391 | static ssize_t |
b807c3d0 | 4392 | tracing_read_dyn_info(struct file *filp, char __user *ubuf, |
bc0c38d1 SR |
4393 | size_t cnt, loff_t *ppos) |
4394 | { | |
a26a2a27 SR |
4395 | static char ftrace_dyn_info_buffer[1024]; |
4396 | static DEFINE_MUTEX(dyn_info_mutex); | |
bc0c38d1 | 4397 | unsigned long *p = filp->private_data; |
b807c3d0 | 4398 | char *buf = ftrace_dyn_info_buffer; |
a26a2a27 | 4399 | int size = ARRAY_SIZE(ftrace_dyn_info_buffer); |
bc0c38d1 SR |
4400 | int r; |
4401 | ||
b807c3d0 SR |
4402 | mutex_lock(&dyn_info_mutex); |
4403 | r = sprintf(buf, "%ld ", *p); | |
4bf39a94 | 4404 | |
a26a2a27 | 4405 | r += ftrace_arch_read_dyn_info(buf+r, (size-1)-r); |
b807c3d0 SR |
4406 | buf[r++] = '\n'; |
4407 | ||
4408 | r = simple_read_from_buffer(ubuf, cnt, ppos, buf, r); | |
4409 | ||
4410 | mutex_unlock(&dyn_info_mutex); | |
4411 | ||
4412 | return r; | |
bc0c38d1 SR |
4413 | } |
4414 | ||
5e2336a0 | 4415 | static const struct file_operations tracing_dyn_info_fops = { |
4bf39a94 | 4416 | .open = tracing_open_generic, |
b807c3d0 | 4417 | .read = tracing_read_dyn_info, |
b444786f | 4418 | .llseek = generic_file_llseek, |
bc0c38d1 SR |
4419 | }; |
4420 | #endif | |
4421 | ||
4422 | static struct dentry *d_tracer; | |
4423 | ||
4424 | struct dentry *tracing_init_dentry(void) | |
4425 | { | |
4426 | static int once; | |
4427 | ||
4428 | if (d_tracer) | |
4429 | return d_tracer; | |
4430 | ||
3e1f60b8 FW |
4431 | if (!debugfs_initialized()) |
4432 | return NULL; | |
4433 | ||
bc0c38d1 SR |
4434 | d_tracer = debugfs_create_dir("tracing", NULL); |
4435 | ||
4436 | if (!d_tracer && !once) { | |
4437 | once = 1; | |
4438 | pr_warning("Could not create debugfs directory 'tracing'\n"); | |
4439 | return NULL; | |
4440 | } | |
4441 | ||
4442 | return d_tracer; | |
4443 | } | |
4444 | ||
b04cc6b1 FW |
4445 | static struct dentry *d_percpu; |
4446 | ||
4447 | struct dentry *tracing_dentry_percpu(void) | |
4448 | { | |
4449 | static int once; | |
4450 | struct dentry *d_tracer; | |
4451 | ||
4452 | if (d_percpu) | |
4453 | return d_percpu; | |
4454 | ||
4455 | d_tracer = tracing_init_dentry(); | |
4456 | ||
4457 | if (!d_tracer) | |
4458 | return NULL; | |
4459 | ||
4460 | d_percpu = debugfs_create_dir("per_cpu", d_tracer); | |
4461 | ||
4462 | if (!d_percpu && !once) { | |
4463 | once = 1; | |
4464 | pr_warning("Could not create debugfs directory 'per_cpu'\n"); | |
4465 | return NULL; | |
4466 | } | |
4467 | ||
4468 | return d_percpu; | |
4469 | } | |
4470 | ||
4471 | static void tracing_init_debugfs_percpu(long cpu) | |
4472 | { | |
4473 | struct dentry *d_percpu = tracing_dentry_percpu(); | |
5452af66 | 4474 | struct dentry *d_cpu; |
dd49a38c | 4475 | char cpu_dir[30]; /* 30 characters should be more than enough */ |
b04cc6b1 | 4476 | |
0a3d7ce7 NK |
4477 | if (!d_percpu) |
4478 | return; | |
4479 | ||
dd49a38c | 4480 | snprintf(cpu_dir, 30, "cpu%ld", cpu); |
8656e7a2 FW |
4481 | d_cpu = debugfs_create_dir(cpu_dir, d_percpu); |
4482 | if (!d_cpu) { | |
4483 | pr_warning("Could not create debugfs '%s' entry\n", cpu_dir); | |
4484 | return; | |
4485 | } | |
b04cc6b1 | 4486 | |
8656e7a2 | 4487 | /* per cpu trace_pipe */ |
5452af66 FW |
4488 | trace_create_file("trace_pipe", 0444, d_cpu, |
4489 | (void *) cpu, &tracing_pipe_fops); | |
b04cc6b1 FW |
4490 | |
4491 | /* per cpu trace */ | |
5452af66 FW |
4492 | trace_create_file("trace", 0644, d_cpu, |
4493 | (void *) cpu, &tracing_fops); | |
7f96f93f | 4494 | |
5452af66 FW |
4495 | trace_create_file("trace_pipe_raw", 0444, d_cpu, |
4496 | (void *) cpu, &tracing_buffers_fops); | |
7f96f93f | 4497 | |
c8d77183 SR |
4498 | trace_create_file("stats", 0444, d_cpu, |
4499 | (void *) cpu, &tracing_stats_fops); | |
438ced17 VN |
4500 | |
4501 | trace_create_file("buffer_size_kb", 0444, d_cpu, | |
4502 | (void *) cpu, &tracing_entries_fops); | |
b04cc6b1 FW |
4503 | } |
4504 | ||
60a11774 SR |
4505 | #ifdef CONFIG_FTRACE_SELFTEST |
4506 | /* Let selftest have access to static functions in this file */ | |
4507 | #include "trace_selftest.c" | |
4508 | #endif | |
4509 | ||
577b785f SR |
4510 | struct trace_option_dentry { |
4511 | struct tracer_opt *opt; | |
4512 | struct tracer_flags *flags; | |
4513 | struct dentry *entry; | |
4514 | }; | |
4515 | ||
4516 | static ssize_t | |
4517 | trace_options_read(struct file *filp, char __user *ubuf, size_t cnt, | |
4518 | loff_t *ppos) | |
4519 | { | |
4520 | struct trace_option_dentry *topt = filp->private_data; | |
4521 | char *buf; | |
4522 | ||
4523 | if (topt->flags->val & topt->opt->bit) | |
4524 | buf = "1\n"; | |
4525 | else | |
4526 | buf = "0\n"; | |
4527 | ||
4528 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, 2); | |
4529 | } | |
4530 | ||
4531 | static ssize_t | |
4532 | trace_options_write(struct file *filp, const char __user *ubuf, size_t cnt, | |
4533 | loff_t *ppos) | |
4534 | { | |
4535 | struct trace_option_dentry *topt = filp->private_data; | |
4536 | unsigned long val; | |
577b785f SR |
4537 | int ret; |
4538 | ||
22fe9b54 PH |
4539 | ret = kstrtoul_from_user(ubuf, cnt, 10, &val); |
4540 | if (ret) | |
577b785f SR |
4541 | return ret; |
4542 | ||
8d18eaaf LZ |
4543 | if (val != 0 && val != 1) |
4544 | return -EINVAL; | |
577b785f | 4545 | |
8d18eaaf | 4546 | if (!!(topt->flags->val & topt->opt->bit) != val) { |
577b785f | 4547 | mutex_lock(&trace_types_lock); |
8d18eaaf | 4548 | ret = __set_tracer_option(current_trace, topt->flags, |
c757bea9 | 4549 | topt->opt, !val); |
577b785f SR |
4550 | mutex_unlock(&trace_types_lock); |
4551 | if (ret) | |
4552 | return ret; | |
577b785f SR |
4553 | } |
4554 | ||
4555 | *ppos += cnt; | |
4556 | ||
4557 | return cnt; | |
4558 | } | |
4559 | ||
4560 | ||
4561 | static const struct file_operations trace_options_fops = { | |
4562 | .open = tracing_open_generic, | |
4563 | .read = trace_options_read, | |
4564 | .write = trace_options_write, | |
b444786f | 4565 | .llseek = generic_file_llseek, |
577b785f SR |
4566 | }; |
4567 | ||
a8259075 SR |
4568 | static ssize_t |
4569 | trace_options_core_read(struct file *filp, char __user *ubuf, size_t cnt, | |
4570 | loff_t *ppos) | |
4571 | { | |
4572 | long index = (long)filp->private_data; | |
4573 | char *buf; | |
4574 | ||
4575 | if (trace_flags & (1 << index)) | |
4576 | buf = "1\n"; | |
4577 | else | |
4578 | buf = "0\n"; | |
4579 | ||
4580 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, 2); | |
4581 | } | |
4582 | ||
4583 | static ssize_t | |
4584 | trace_options_core_write(struct file *filp, const char __user *ubuf, size_t cnt, | |
4585 | loff_t *ppos) | |
4586 | { | |
4587 | long index = (long)filp->private_data; | |
a8259075 SR |
4588 | unsigned long val; |
4589 | int ret; | |
4590 | ||
22fe9b54 PH |
4591 | ret = kstrtoul_from_user(ubuf, cnt, 10, &val); |
4592 | if (ret) | |
a8259075 SR |
4593 | return ret; |
4594 | ||
f2d84b65 | 4595 | if (val != 0 && val != 1) |
a8259075 | 4596 | return -EINVAL; |
f2d84b65 | 4597 | set_tracer_flags(1 << index, val); |
a8259075 SR |
4598 | |
4599 | *ppos += cnt; | |
4600 | ||
4601 | return cnt; | |
4602 | } | |
4603 | ||
a8259075 SR |
4604 | static const struct file_operations trace_options_core_fops = { |
4605 | .open = tracing_open_generic, | |
4606 | .read = trace_options_core_read, | |
4607 | .write = trace_options_core_write, | |
b444786f | 4608 | .llseek = generic_file_llseek, |
a8259075 SR |
4609 | }; |
4610 | ||
5452af66 | 4611 | struct dentry *trace_create_file(const char *name, |
f4ae40a6 | 4612 | umode_t mode, |
5452af66 FW |
4613 | struct dentry *parent, |
4614 | void *data, | |
4615 | const struct file_operations *fops) | |
4616 | { | |
4617 | struct dentry *ret; | |
4618 | ||
4619 | ret = debugfs_create_file(name, mode, parent, data, fops); | |
4620 | if (!ret) | |
4621 | pr_warning("Could not create debugfs '%s' entry\n", name); | |
4622 | ||
4623 | return ret; | |
4624 | } | |
4625 | ||
4626 | ||
a8259075 SR |
4627 | static struct dentry *trace_options_init_dentry(void) |
4628 | { | |
4629 | struct dentry *d_tracer; | |
4630 | static struct dentry *t_options; | |
4631 | ||
4632 | if (t_options) | |
4633 | return t_options; | |
4634 | ||
4635 | d_tracer = tracing_init_dentry(); | |
4636 | if (!d_tracer) | |
4637 | return NULL; | |
4638 | ||
4639 | t_options = debugfs_create_dir("options", d_tracer); | |
4640 | if (!t_options) { | |
4641 | pr_warning("Could not create debugfs directory 'options'\n"); | |
4642 | return NULL; | |
4643 | } | |
4644 | ||
4645 | return t_options; | |
4646 | } | |
4647 | ||
577b785f SR |
4648 | static void |
4649 | create_trace_option_file(struct trace_option_dentry *topt, | |
4650 | struct tracer_flags *flags, | |
4651 | struct tracer_opt *opt) | |
4652 | { | |
4653 | struct dentry *t_options; | |
577b785f SR |
4654 | |
4655 | t_options = trace_options_init_dentry(); | |
4656 | if (!t_options) | |
4657 | return; | |
4658 | ||
4659 | topt->flags = flags; | |
4660 | topt->opt = opt; | |
4661 | ||
5452af66 | 4662 | topt->entry = trace_create_file(opt->name, 0644, t_options, topt, |
577b785f SR |
4663 | &trace_options_fops); |
4664 | ||
577b785f SR |
4665 | } |
4666 | ||
4667 | static struct trace_option_dentry * | |
4668 | create_trace_option_files(struct tracer *tracer) | |
4669 | { | |
4670 | struct trace_option_dentry *topts; | |
4671 | struct tracer_flags *flags; | |
4672 | struct tracer_opt *opts; | |
4673 | int cnt; | |
4674 | ||
4675 | if (!tracer) | |
4676 | return NULL; | |
4677 | ||
4678 | flags = tracer->flags; | |
4679 | ||
4680 | if (!flags || !flags->opts) | |
4681 | return NULL; | |
4682 | ||
4683 | opts = flags->opts; | |
4684 | ||
4685 | for (cnt = 0; opts[cnt].name; cnt++) | |
4686 | ; | |
4687 | ||
0cfe8245 | 4688 | topts = kcalloc(cnt + 1, sizeof(*topts), GFP_KERNEL); |
577b785f SR |
4689 | if (!topts) |
4690 | return NULL; | |
4691 | ||
4692 | for (cnt = 0; opts[cnt].name; cnt++) | |
4693 | create_trace_option_file(&topts[cnt], flags, | |
4694 | &opts[cnt]); | |
4695 | ||
4696 | return topts; | |
4697 | } | |
4698 | ||
4699 | static void | |
4700 | destroy_trace_option_files(struct trace_option_dentry *topts) | |
4701 | { | |
4702 | int cnt; | |
4703 | ||
4704 | if (!topts) | |
4705 | return; | |
4706 | ||
4707 | for (cnt = 0; topts[cnt].opt; cnt++) { | |
4708 | if (topts[cnt].entry) | |
4709 | debugfs_remove(topts[cnt].entry); | |
4710 | } | |
4711 | ||
4712 | kfree(topts); | |
4713 | } | |
4714 | ||
a8259075 SR |
4715 | static struct dentry * |
4716 | create_trace_option_core_file(const char *option, long index) | |
4717 | { | |
4718 | struct dentry *t_options; | |
a8259075 SR |
4719 | |
4720 | t_options = trace_options_init_dentry(); | |
4721 | if (!t_options) | |
4722 | return NULL; | |
4723 | ||
5452af66 | 4724 | return trace_create_file(option, 0644, t_options, (void *)index, |
a8259075 | 4725 | &trace_options_core_fops); |
a8259075 SR |
4726 | } |
4727 | ||
4728 | static __init void create_trace_options_dir(void) | |
4729 | { | |
4730 | struct dentry *t_options; | |
a8259075 SR |
4731 | int i; |
4732 | ||
4733 | t_options = trace_options_init_dentry(); | |
4734 | if (!t_options) | |
4735 | return; | |
4736 | ||
5452af66 FW |
4737 | for (i = 0; trace_options[i]; i++) |
4738 | create_trace_option_core_file(trace_options[i], i); | |
a8259075 SR |
4739 | } |
4740 | ||
499e5470 SR |
4741 | static ssize_t |
4742 | rb_simple_read(struct file *filp, char __user *ubuf, | |
4743 | size_t cnt, loff_t *ppos) | |
4744 | { | |
348f0fc2 SR |
4745 | struct trace_array *tr = filp->private_data; |
4746 | struct ring_buffer *buffer = tr->buffer; | |
499e5470 SR |
4747 | char buf[64]; |
4748 | int r; | |
4749 | ||
4750 | if (buffer) | |
4751 | r = ring_buffer_record_is_on(buffer); | |
4752 | else | |
4753 | r = 0; | |
4754 | ||
4755 | r = sprintf(buf, "%d\n", r); | |
4756 | ||
4757 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, r); | |
4758 | } | |
4759 | ||
4760 | static ssize_t | |
4761 | rb_simple_write(struct file *filp, const char __user *ubuf, | |
4762 | size_t cnt, loff_t *ppos) | |
4763 | { | |
348f0fc2 SR |
4764 | struct trace_array *tr = filp->private_data; |
4765 | struct ring_buffer *buffer = tr->buffer; | |
499e5470 SR |
4766 | unsigned long val; |
4767 | int ret; | |
4768 | ||
4769 | ret = kstrtoul_from_user(ubuf, cnt, 10, &val); | |
4770 | if (ret) | |
4771 | return ret; | |
4772 | ||
4773 | if (buffer) { | |
4774 | if (val) | |
4775 | ring_buffer_record_on(buffer); | |
4776 | else | |
4777 | ring_buffer_record_off(buffer); | |
4778 | } | |
4779 | ||
4780 | (*ppos)++; | |
4781 | ||
4782 | return cnt; | |
4783 | } | |
4784 | ||
4785 | static const struct file_operations rb_simple_fops = { | |
4786 | .open = tracing_open_generic, | |
4787 | .read = rb_simple_read, | |
4788 | .write = rb_simple_write, | |
4789 | .llseek = default_llseek, | |
4790 | }; | |
4791 | ||
b5ad384e | 4792 | static __init int tracer_init_debugfs(void) |
bc0c38d1 SR |
4793 | { |
4794 | struct dentry *d_tracer; | |
b04cc6b1 | 4795 | int cpu; |
bc0c38d1 | 4796 | |
7e53bd42 LJ |
4797 | trace_access_lock_init(); |
4798 | ||
bc0c38d1 SR |
4799 | d_tracer = tracing_init_dentry(); |
4800 | ||
5452af66 FW |
4801 | trace_create_file("tracing_enabled", 0644, d_tracer, |
4802 | &global_trace, &tracing_ctrl_fops); | |
bc0c38d1 | 4803 | |
5452af66 FW |
4804 | trace_create_file("trace_options", 0644, d_tracer, |
4805 | NULL, &tracing_iter_fops); | |
bc0c38d1 | 4806 | |
5452af66 FW |
4807 | trace_create_file("tracing_cpumask", 0644, d_tracer, |
4808 | NULL, &tracing_cpumask_fops); | |
4809 | ||
4810 | trace_create_file("trace", 0644, d_tracer, | |
4811 | (void *) TRACE_PIPE_ALL_CPU, &tracing_fops); | |
a8259075 | 4812 | |
5452af66 FW |
4813 | trace_create_file("available_tracers", 0444, d_tracer, |
4814 | &global_trace, &show_traces_fops); | |
4815 | ||
339ae5d3 | 4816 | trace_create_file("current_tracer", 0644, d_tracer, |
5452af66 FW |
4817 | &global_trace, &set_tracer_fops); |
4818 | ||
5d4a9dba | 4819 | #ifdef CONFIG_TRACER_MAX_TRACE |
5452af66 FW |
4820 | trace_create_file("tracing_max_latency", 0644, d_tracer, |
4821 | &tracing_max_latency, &tracing_max_lat_fops); | |
0e950173 | 4822 | #endif |
5452af66 FW |
4823 | |
4824 | trace_create_file("tracing_thresh", 0644, d_tracer, | |
4825 | &tracing_thresh, &tracing_max_lat_fops); | |
a8259075 | 4826 | |
339ae5d3 | 4827 | trace_create_file("README", 0444, d_tracer, |
5452af66 FW |
4828 | NULL, &tracing_readme_fops); |
4829 | ||
4830 | trace_create_file("trace_pipe", 0444, d_tracer, | |
b04cc6b1 | 4831 | (void *) TRACE_PIPE_ALL_CPU, &tracing_pipe_fops); |
5452af66 FW |
4832 | |
4833 | trace_create_file("buffer_size_kb", 0644, d_tracer, | |
438ced17 | 4834 | (void *) RING_BUFFER_ALL_CPUS, &tracing_entries_fops); |
5452af66 | 4835 | |
f81ab074 VN |
4836 | trace_create_file("buffer_total_size_kb", 0444, d_tracer, |
4837 | &global_trace, &tracing_total_entries_fops); | |
4838 | ||
4f271a2a VN |
4839 | trace_create_file("free_buffer", 0644, d_tracer, |
4840 | &global_trace, &tracing_free_buffer_fops); | |
4841 | ||
5452af66 FW |
4842 | trace_create_file("trace_marker", 0220, d_tracer, |
4843 | NULL, &tracing_mark_fops); | |
5bf9a1ee | 4844 | |
69abe6a5 AP |
4845 | trace_create_file("saved_cmdlines", 0444, d_tracer, |
4846 | NULL, &tracing_saved_cmdlines_fops); | |
5bf9a1ee | 4847 | |
5079f326 Z |
4848 | trace_create_file("trace_clock", 0644, d_tracer, NULL, |
4849 | &trace_clock_fops); | |
4850 | ||
499e5470 | 4851 | trace_create_file("tracing_on", 0644, d_tracer, |
348f0fc2 | 4852 | &global_trace, &rb_simple_fops); |
499e5470 | 4853 | |
bc0c38d1 | 4854 | #ifdef CONFIG_DYNAMIC_FTRACE |
5452af66 FW |
4855 | trace_create_file("dyn_ftrace_total_info", 0444, d_tracer, |
4856 | &ftrace_update_tot_cnt, &tracing_dyn_info_fops); | |
bc0c38d1 | 4857 | #endif |
b04cc6b1 | 4858 | |
5452af66 FW |
4859 | create_trace_options_dir(); |
4860 | ||
b04cc6b1 FW |
4861 | for_each_tracing_cpu(cpu) |
4862 | tracing_init_debugfs_percpu(cpu); | |
4863 | ||
b5ad384e | 4864 | return 0; |
bc0c38d1 SR |
4865 | } |
4866 | ||
3f5a54e3 SR |
4867 | static int trace_panic_handler(struct notifier_block *this, |
4868 | unsigned long event, void *unused) | |
4869 | { | |
944ac425 | 4870 | if (ftrace_dump_on_oops) |
cecbca96 | 4871 | ftrace_dump(ftrace_dump_on_oops); |
3f5a54e3 SR |
4872 | return NOTIFY_OK; |
4873 | } | |
4874 | ||
4875 | static struct notifier_block trace_panic_notifier = { | |
4876 | .notifier_call = trace_panic_handler, | |
4877 | .next = NULL, | |
4878 | .priority = 150 /* priority: INT_MAX >= x >= 0 */ | |
4879 | }; | |
4880 | ||
4881 | static int trace_die_handler(struct notifier_block *self, | |
4882 | unsigned long val, | |
4883 | void *data) | |
4884 | { | |
4885 | switch (val) { | |
4886 | case DIE_OOPS: | |
944ac425 | 4887 | if (ftrace_dump_on_oops) |
cecbca96 | 4888 | ftrace_dump(ftrace_dump_on_oops); |
3f5a54e3 SR |
4889 | break; |
4890 | default: | |
4891 | break; | |
4892 | } | |
4893 | return NOTIFY_OK; | |
4894 | } | |
4895 | ||
4896 | static struct notifier_block trace_die_notifier = { | |
4897 | .notifier_call = trace_die_handler, | |
4898 | .priority = 200 | |
4899 | }; | |
4900 | ||
4901 | /* | |
4902 | * printk is set to max of 1024, we really don't need it that big. | |
4903 | * Nothing should be printing 1000 characters anyway. | |
4904 | */ | |
4905 | #define TRACE_MAX_PRINT 1000 | |
4906 | ||
4907 | /* | |
4908 | * Define here KERN_TRACE so that we have one place to modify | |
4909 | * it if we decide to change what log level the ftrace dump | |
4910 | * should be at. | |
4911 | */ | |
428aee14 | 4912 | #define KERN_TRACE KERN_EMERG |
3f5a54e3 | 4913 | |
955b61e5 | 4914 | void |
3f5a54e3 SR |
4915 | trace_printk_seq(struct trace_seq *s) |
4916 | { | |
4917 | /* Probably should print a warning here. */ | |
4918 | if (s->len >= 1000) | |
4919 | s->len = 1000; | |
4920 | ||
4921 | /* should be zero ended, but we are paranoid. */ | |
4922 | s->buffer[s->len] = 0; | |
4923 | ||
4924 | printk(KERN_TRACE "%s", s->buffer); | |
4925 | ||
f9520750 | 4926 | trace_seq_init(s); |
3f5a54e3 SR |
4927 | } |
4928 | ||
955b61e5 JW |
4929 | void trace_init_global_iter(struct trace_iterator *iter) |
4930 | { | |
4931 | iter->tr = &global_trace; | |
4932 | iter->trace = current_trace; | |
4933 | iter->cpu_file = TRACE_PIPE_ALL_CPU; | |
4934 | } | |
4935 | ||
cecbca96 FW |
4936 | static void |
4937 | __ftrace_dump(bool disable_tracing, enum ftrace_dump_mode oops_dump_mode) | |
3f5a54e3 | 4938 | { |
445c8951 | 4939 | static arch_spinlock_t ftrace_dump_lock = |
edc35bd7 | 4940 | (arch_spinlock_t)__ARCH_SPIN_LOCK_UNLOCKED; |
3f5a54e3 SR |
4941 | /* use static because iter can be a bit big for the stack */ |
4942 | static struct trace_iterator iter; | |
cf586b61 | 4943 | unsigned int old_userobj; |
3f5a54e3 | 4944 | static int dump_ran; |
d769041f SR |
4945 | unsigned long flags; |
4946 | int cnt = 0, cpu; | |
3f5a54e3 SR |
4947 | |
4948 | /* only one dump */ | |
cd891ae0 | 4949 | local_irq_save(flags); |
0199c4e6 | 4950 | arch_spin_lock(&ftrace_dump_lock); |
3f5a54e3 SR |
4951 | if (dump_ran) |
4952 | goto out; | |
4953 | ||
4954 | dump_ran = 1; | |
4955 | ||
0ee6b6cf | 4956 | tracing_off(); |
cf586b61 | 4957 | |
e0a413f6 SR |
4958 | /* Did function tracer already get disabled? */ |
4959 | if (ftrace_is_dead()) { | |
4960 | printk("# WARNING: FUNCTION TRACING IS CORRUPTED\n"); | |
4961 | printk("# MAY BE MISSING FUNCTION EVENTS\n"); | |
4962 | } | |
4963 | ||
cf586b61 FW |
4964 | if (disable_tracing) |
4965 | ftrace_kill(); | |
3f5a54e3 | 4966 | |
955b61e5 JW |
4967 | trace_init_global_iter(&iter); |
4968 | ||
d769041f | 4969 | for_each_tracing_cpu(cpu) { |
955b61e5 | 4970 | atomic_inc(&iter.tr->data[cpu]->disabled); |
d769041f SR |
4971 | } |
4972 | ||
cf586b61 FW |
4973 | old_userobj = trace_flags & TRACE_ITER_SYM_USEROBJ; |
4974 | ||
b54d3de9 TE |
4975 | /* don't look at user memory in panic mode */ |
4976 | trace_flags &= ~TRACE_ITER_SYM_USEROBJ; | |
4977 | ||
e543ad76 | 4978 | /* Simulate the iterator */ |
3f5a54e3 SR |
4979 | iter.tr = &global_trace; |
4980 | iter.trace = current_trace; | |
cecbca96 FW |
4981 | |
4982 | switch (oops_dump_mode) { | |
4983 | case DUMP_ALL: | |
4984 | iter.cpu_file = TRACE_PIPE_ALL_CPU; | |
4985 | break; | |
4986 | case DUMP_ORIG: | |
4987 | iter.cpu_file = raw_smp_processor_id(); | |
4988 | break; | |
4989 | case DUMP_NONE: | |
4990 | goto out_enable; | |
4991 | default: | |
4992 | printk(KERN_TRACE "Bad dumping mode, switching to all CPUs dump\n"); | |
4993 | iter.cpu_file = TRACE_PIPE_ALL_CPU; | |
4994 | } | |
4995 | ||
4996 | printk(KERN_TRACE "Dumping ftrace buffer:\n"); | |
3f5a54e3 SR |
4997 | |
4998 | /* | |
4999 | * We need to stop all tracing on all CPUS to read the | |
5000 | * the next buffer. This is a bit expensive, but is | |
5001 | * not done often. We fill all what we can read, | |
5002 | * and then release the locks again. | |
5003 | */ | |
5004 | ||
3f5a54e3 SR |
5005 | while (!trace_empty(&iter)) { |
5006 | ||
5007 | if (!cnt) | |
5008 | printk(KERN_TRACE "---------------------------------\n"); | |
5009 | ||
5010 | cnt++; | |
5011 | ||
5012 | /* reset all but tr, trace, and overruns */ | |
5013 | memset(&iter.seq, 0, | |
5014 | sizeof(struct trace_iterator) - | |
5015 | offsetof(struct trace_iterator, seq)); | |
5016 | iter.iter_flags |= TRACE_FILE_LAT_FMT; | |
5017 | iter.pos = -1; | |
5018 | ||
955b61e5 | 5019 | if (trace_find_next_entry_inc(&iter) != NULL) { |
74e7ff8c LJ |
5020 | int ret; |
5021 | ||
5022 | ret = print_trace_line(&iter); | |
5023 | if (ret != TRACE_TYPE_NO_CONSUME) | |
5024 | trace_consume(&iter); | |
3f5a54e3 | 5025 | } |
b892e5c8 | 5026 | touch_nmi_watchdog(); |
3f5a54e3 SR |
5027 | |
5028 | trace_printk_seq(&iter.seq); | |
5029 | } | |
5030 | ||
5031 | if (!cnt) | |
5032 | printk(KERN_TRACE " (ftrace buffer empty)\n"); | |
5033 | else | |
5034 | printk(KERN_TRACE "---------------------------------\n"); | |
5035 | ||
cecbca96 | 5036 | out_enable: |
cf586b61 FW |
5037 | /* Re-enable tracing if requested */ |
5038 | if (!disable_tracing) { | |
5039 | trace_flags |= old_userobj; | |
5040 | ||
5041 | for_each_tracing_cpu(cpu) { | |
955b61e5 | 5042 | atomic_dec(&iter.tr->data[cpu]->disabled); |
cf586b61 FW |
5043 | } |
5044 | tracing_on(); | |
5045 | } | |
5046 | ||
3f5a54e3 | 5047 | out: |
0199c4e6 | 5048 | arch_spin_unlock(&ftrace_dump_lock); |
cd891ae0 | 5049 | local_irq_restore(flags); |
3f5a54e3 SR |
5050 | } |
5051 | ||
cf586b61 | 5052 | /* By default: disable tracing after the dump */ |
cecbca96 | 5053 | void ftrace_dump(enum ftrace_dump_mode oops_dump_mode) |
cf586b61 | 5054 | { |
cecbca96 | 5055 | __ftrace_dump(true, oops_dump_mode); |
cf586b61 | 5056 | } |
a8eecf22 | 5057 | EXPORT_SYMBOL_GPL(ftrace_dump); |
cf586b61 | 5058 | |
3928a8a2 | 5059 | __init static int tracer_alloc_buffers(void) |
bc0c38d1 | 5060 | { |
73c5162a | 5061 | int ring_buf_size; |
750912fa | 5062 | enum ring_buffer_flags rb_flags; |
4c11d7ae | 5063 | int i; |
9e01c1b7 | 5064 | int ret = -ENOMEM; |
4c11d7ae | 5065 | |
750912fa | 5066 | |
9e01c1b7 RR |
5067 | if (!alloc_cpumask_var(&tracing_buffer_mask, GFP_KERNEL)) |
5068 | goto out; | |
5069 | ||
5070 | if (!alloc_cpumask_var(&tracing_cpumask, GFP_KERNEL)) | |
5071 | goto out_free_buffer_mask; | |
4c11d7ae | 5072 | |
07d777fe SR |
5073 | /* Only allocate trace_printk buffers if a trace_printk exists */ |
5074 | if (__stop___trace_bprintk_fmt != __start___trace_bprintk_fmt) | |
5075 | trace_printk_init_buffers(); | |
5076 | ||
73c5162a SR |
5077 | /* To save memory, keep the ring buffer size to its minimum */ |
5078 | if (ring_buffer_expanded) | |
5079 | ring_buf_size = trace_buf_size; | |
5080 | else | |
5081 | ring_buf_size = 1; | |
5082 | ||
750912fa DS |
5083 | rb_flags = trace_flags & TRACE_ITER_OVERWRITE ? RB_FL_OVERWRITE : 0; |
5084 | ||
9e01c1b7 RR |
5085 | cpumask_copy(tracing_buffer_mask, cpu_possible_mask); |
5086 | cpumask_copy(tracing_cpumask, cpu_all_mask); | |
5087 | ||
5088 | /* TODO: make the number of buffers hot pluggable with CPUS */ | |
750912fa | 5089 | global_trace.buffer = ring_buffer_alloc(ring_buf_size, rb_flags); |
3928a8a2 SR |
5090 | if (!global_trace.buffer) { |
5091 | printk(KERN_ERR "tracer: failed to allocate ring buffer!\n"); | |
5092 | WARN_ON(1); | |
9e01c1b7 | 5093 | goto out_free_cpumask; |
4c11d7ae | 5094 | } |
499e5470 SR |
5095 | if (global_trace.buffer_disabled) |
5096 | tracing_off(); | |
4c11d7ae | 5097 | |
9e01c1b7 | 5098 | |
4c11d7ae | 5099 | #ifdef CONFIG_TRACER_MAX_TRACE |
750912fa | 5100 | max_tr.buffer = ring_buffer_alloc(1, rb_flags); |
3928a8a2 SR |
5101 | if (!max_tr.buffer) { |
5102 | printk(KERN_ERR "tracer: failed to allocate max ring buffer!\n"); | |
5103 | WARN_ON(1); | |
5104 | ring_buffer_free(global_trace.buffer); | |
9e01c1b7 | 5105 | goto out_free_cpumask; |
4c11d7ae | 5106 | } |
a98a3c3f | 5107 | #endif |
ab46428c | 5108 | |
4c11d7ae | 5109 | /* Allocate the first page for all buffers */ |
ab46428c | 5110 | for_each_tracing_cpu(i) { |
566b0aaf | 5111 | global_trace.data[i] = &per_cpu(global_trace_cpu, i); |
9705f69e | 5112 | max_tr.data[i] = &per_cpu(max_tr_data, i); |
4c11d7ae | 5113 | } |
438ced17 | 5114 | |
a591c73f VN |
5115 | set_buffer_entries(&global_trace, |
5116 | ring_buffer_size(global_trace.buffer, 0)); | |
438ced17 VN |
5117 | #ifdef CONFIG_TRACER_MAX_TRACE |
5118 | set_buffer_entries(&max_tr, 1); | |
5119 | #endif | |
bc0c38d1 | 5120 | |
bc0c38d1 SR |
5121 | trace_init_cmdlines(); |
5122 | ||
43a15386 | 5123 | register_tracer(&nop_trace); |
79fb0768 | 5124 | current_trace = &nop_trace; |
60a11774 SR |
5125 | /* All seems OK, enable tracing */ |
5126 | tracing_disabled = 0; | |
3928a8a2 | 5127 | |
3f5a54e3 SR |
5128 | atomic_notifier_chain_register(&panic_notifier_list, |
5129 | &trace_panic_notifier); | |
5130 | ||
5131 | register_die_notifier(&trace_die_notifier); | |
2fc1dfbe FW |
5132 | |
5133 | return 0; | |
3f5a54e3 | 5134 | |
9e01c1b7 RR |
5135 | out_free_cpumask: |
5136 | free_cpumask_var(tracing_cpumask); | |
5137 | out_free_buffer_mask: | |
5138 | free_cpumask_var(tracing_buffer_mask); | |
5139 | out: | |
5140 | return ret; | |
bc0c38d1 | 5141 | } |
b2821ae6 SR |
5142 | |
5143 | __init static int clear_boot_tracer(void) | |
5144 | { | |
5145 | /* | |
5146 | * The default tracer at boot buffer is an init section. | |
5147 | * This function is called in lateinit. If we did not | |
5148 | * find the boot tracer, then clear it out, to prevent | |
5149 | * later registration from accessing the buffer that is | |
5150 | * about to be freed. | |
5151 | */ | |
5152 | if (!default_bootup_tracer) | |
5153 | return 0; | |
5154 | ||
5155 | printk(KERN_INFO "ftrace bootup tracer '%s' not registered.\n", | |
5156 | default_bootup_tracer); | |
5157 | default_bootup_tracer = NULL; | |
5158 | ||
5159 | return 0; | |
5160 | } | |
5161 | ||
b5ad384e FW |
5162 | early_initcall(tracer_alloc_buffers); |
5163 | fs_initcall(tracer_init_debugfs); | |
b2821ae6 | 5164 | late_initcall(clear_boot_tracer); |