Commit | Line | Data |
---|---|---|
bc0c38d1 SR |
1 | /* |
2 | * ring buffer based function tracer | |
3 | * | |
4 | * Copyright (C) 2007-2008 Steven Rostedt <srostedt@redhat.com> | |
5 | * Copyright (C) 2008 Ingo Molnar <mingo@redhat.com> | |
6 | * | |
7 | * Originally taken from the RT patch by: | |
8 | * Arnaldo Carvalho de Melo <acme@redhat.com> | |
9 | * | |
10 | * Based on code from the latency_tracer, that is: | |
11 | * Copyright (C) 2004-2006 Ingo Molnar | |
12 | * Copyright (C) 2004 William Lee Irwin III | |
13 | */ | |
2cadf913 | 14 | #include <linux/ring_buffer.h> |
273b281f | 15 | #include <generated/utsrelease.h> |
2cadf913 SR |
16 | #include <linux/stacktrace.h> |
17 | #include <linux/writeback.h> | |
bc0c38d1 SR |
18 | #include <linux/kallsyms.h> |
19 | #include <linux/seq_file.h> | |
3f5a54e3 | 20 | #include <linux/notifier.h> |
2cadf913 | 21 | #include <linux/irqflags.h> |
bc0c38d1 | 22 | #include <linux/debugfs.h> |
4c11d7ae | 23 | #include <linux/pagemap.h> |
bc0c38d1 SR |
24 | #include <linux/hardirq.h> |
25 | #include <linux/linkage.h> | |
26 | #include <linux/uaccess.h> | |
2cadf913 | 27 | #include <linux/kprobes.h> |
bc0c38d1 SR |
28 | #include <linux/ftrace.h> |
29 | #include <linux/module.h> | |
30 | #include <linux/percpu.h> | |
2cadf913 | 31 | #include <linux/splice.h> |
3f5a54e3 | 32 | #include <linux/kdebug.h> |
5f0c6c03 | 33 | #include <linux/string.h> |
7e53bd42 | 34 | #include <linux/rwsem.h> |
5a0e3ad6 | 35 | #include <linux/slab.h> |
bc0c38d1 SR |
36 | #include <linux/ctype.h> |
37 | #include <linux/init.h> | |
2a2cc8f7 | 38 | #include <linux/poll.h> |
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 | 330 | TRACE_ITER_GRAPH_TIME | TRACE_ITER_RECORD_CMD | TRACE_ITER_OVERWRITE | |
5224c3a3 | 331 | TRACE_ITER_IRQ_INFO | TRACE_ITER_MARKERS; |
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) | |
f2bf1f6f | 374 | ring_buffer_record_off(global_trace.buffer); |
499e5470 SR |
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 | { | |
87abb3b1 | 429 | unsigned long threshold; |
0e950173 TB |
430 | int ret; |
431 | ||
432 | if (!str) | |
433 | return 0; | |
bcd83ea6 | 434 | ret = kstrtoul(str, 0, &threshold); |
0e950173 TB |
435 | if (ret < 0) |
436 | return 0; | |
87abb3b1 | 437 | tracing_thresh = threshold * 1000; |
0e950173 TB |
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", |
5224c3a3 | 473 | "markers", |
bc0c38d1 SR |
474 | NULL |
475 | }; | |
476 | ||
5079f326 Z |
477 | static struct { |
478 | u64 (*func)(void); | |
479 | const char *name; | |
480 | } trace_clocks[] = { | |
481 | { trace_clock_local, "local" }, | |
482 | { trace_clock_global, "global" }, | |
6249687f | 483 | { trace_clock_counter, "counter" }, |
5079f326 Z |
484 | }; |
485 | ||
486 | int trace_clock_id; | |
487 | ||
b63f39ea | 488 | /* |
489 | * trace_parser_get_init - gets the buffer for trace parser | |
490 | */ | |
491 | int trace_parser_get_init(struct trace_parser *parser, int size) | |
492 | { | |
493 | memset(parser, 0, sizeof(*parser)); | |
494 | ||
495 | parser->buffer = kmalloc(size, GFP_KERNEL); | |
496 | if (!parser->buffer) | |
497 | return 1; | |
498 | ||
499 | parser->size = size; | |
500 | return 0; | |
501 | } | |
502 | ||
503 | /* | |
504 | * trace_parser_put - frees the buffer for trace parser | |
505 | */ | |
506 | void trace_parser_put(struct trace_parser *parser) | |
507 | { | |
508 | kfree(parser->buffer); | |
509 | } | |
510 | ||
511 | /* | |
512 | * trace_get_user - reads the user input string separated by space | |
513 | * (matched by isspace(ch)) | |
514 | * | |
515 | * For each string found the 'struct trace_parser' is updated, | |
516 | * and the function returns. | |
517 | * | |
518 | * Returns number of bytes read. | |
519 | * | |
520 | * See kernel/trace/trace.h for 'struct trace_parser' details. | |
521 | */ | |
522 | int trace_get_user(struct trace_parser *parser, const char __user *ubuf, | |
523 | size_t cnt, loff_t *ppos) | |
524 | { | |
525 | char ch; | |
526 | size_t read = 0; | |
527 | ssize_t ret; | |
528 | ||
529 | if (!*ppos) | |
530 | trace_parser_clear(parser); | |
531 | ||
532 | ret = get_user(ch, ubuf++); | |
533 | if (ret) | |
534 | goto out; | |
535 | ||
536 | read++; | |
537 | cnt--; | |
538 | ||
539 | /* | |
540 | * The parser is not finished with the last write, | |
541 | * continue reading the user input without skipping spaces. | |
542 | */ | |
543 | if (!parser->cont) { | |
544 | /* skip white space */ | |
545 | while (cnt && isspace(ch)) { | |
546 | ret = get_user(ch, ubuf++); | |
547 | if (ret) | |
548 | goto out; | |
549 | read++; | |
550 | cnt--; | |
551 | } | |
552 | ||
553 | /* only spaces were written */ | |
554 | if (isspace(ch)) { | |
555 | *ppos += read; | |
556 | ret = read; | |
557 | goto out; | |
558 | } | |
559 | ||
560 | parser->idx = 0; | |
561 | } | |
562 | ||
563 | /* read the non-space input */ | |
564 | while (cnt && !isspace(ch)) { | |
3c235a33 | 565 | if (parser->idx < parser->size - 1) |
b63f39ea | 566 | parser->buffer[parser->idx++] = ch; |
567 | else { | |
568 | ret = -EINVAL; | |
569 | goto out; | |
570 | } | |
571 | ret = get_user(ch, ubuf++); | |
572 | if (ret) | |
573 | goto out; | |
574 | read++; | |
575 | cnt--; | |
576 | } | |
577 | ||
578 | /* We either got finished input or we have to wait for another call. */ | |
579 | if (isspace(ch)) { | |
580 | parser->buffer[parser->idx] = 0; | |
581 | parser->cont = false; | |
582 | } else { | |
583 | parser->cont = true; | |
584 | parser->buffer[parser->idx++] = ch; | |
585 | } | |
586 | ||
587 | *ppos += read; | |
588 | ret = read; | |
589 | ||
590 | out: | |
591 | return ret; | |
592 | } | |
593 | ||
6c6c2796 PP |
594 | ssize_t trace_seq_to_user(struct trace_seq *s, char __user *ubuf, size_t cnt) |
595 | { | |
596 | int len; | |
597 | int ret; | |
598 | ||
2dc5d12b SR |
599 | if (!cnt) |
600 | return 0; | |
601 | ||
6c6c2796 PP |
602 | if (s->len <= s->readpos) |
603 | return -EBUSY; | |
604 | ||
605 | len = s->len - s->readpos; | |
606 | if (cnt > len) | |
607 | cnt = len; | |
608 | ret = copy_to_user(ubuf, s->buffer + s->readpos, cnt); | |
2dc5d12b | 609 | if (ret == cnt) |
6c6c2796 PP |
610 | return -EFAULT; |
611 | ||
2dc5d12b SR |
612 | cnt -= ret; |
613 | ||
e74da523 | 614 | s->readpos += cnt; |
6c6c2796 | 615 | return cnt; |
214023c3 SR |
616 | } |
617 | ||
b8b94265 | 618 | static ssize_t trace_seq_to_buffer(struct trace_seq *s, void *buf, size_t cnt) |
3c56819b EGM |
619 | { |
620 | int len; | |
3c56819b EGM |
621 | |
622 | if (s->len <= s->readpos) | |
623 | return -EBUSY; | |
624 | ||
625 | len = s->len - s->readpos; | |
626 | if (cnt > len) | |
627 | cnt = len; | |
5a26c8f0 | 628 | memcpy(buf, s->buffer + s->readpos, cnt); |
3c56819b | 629 | |
e74da523 | 630 | s->readpos += cnt; |
3c56819b EGM |
631 | return cnt; |
632 | } | |
633 | ||
5d4a9dba SR |
634 | /* |
635 | * ftrace_max_lock is used to protect the swapping of buffers | |
636 | * when taking a max snapshot. The buffers themselves are | |
637 | * protected by per_cpu spinlocks. But the action of the swap | |
638 | * needs its own lock. | |
639 | * | |
445c8951 | 640 | * This is defined as a arch_spinlock_t in order to help |
5d4a9dba SR |
641 | * with performance when lockdep debugging is enabled. |
642 | * | |
643 | * It is also used in other places outside the update_max_tr | |
644 | * so it needs to be defined outside of the | |
645 | * CONFIG_TRACER_MAX_TRACE. | |
646 | */ | |
445c8951 | 647 | static arch_spinlock_t ftrace_max_lock = |
edc35bd7 | 648 | (arch_spinlock_t)__ARCH_SPIN_LOCK_UNLOCKED; |
5d4a9dba | 649 | |
0e950173 TB |
650 | unsigned long __read_mostly tracing_thresh; |
651 | ||
5d4a9dba SR |
652 | #ifdef CONFIG_TRACER_MAX_TRACE |
653 | unsigned long __read_mostly tracing_max_latency; | |
5d4a9dba SR |
654 | |
655 | /* | |
656 | * Copy the new maximum trace into the separate maximum-trace | |
657 | * structure. (this way the maximum trace is permanently saved, | |
658 | * for later retrieval via /sys/kernel/debug/tracing/latency_trace) | |
659 | */ | |
660 | static void | |
661 | __update_max_tr(struct trace_array *tr, struct task_struct *tsk, int cpu) | |
662 | { | |
663 | struct trace_array_cpu *data = tr->data[cpu]; | |
1acaa1b2 | 664 | struct trace_array_cpu *max_data; |
5d4a9dba SR |
665 | |
666 | max_tr.cpu = cpu; | |
667 | max_tr.time_start = data->preempt_timestamp; | |
668 | ||
8248ac05 SR |
669 | max_data = max_tr.data[cpu]; |
670 | max_data->saved_latency = tracing_max_latency; | |
671 | max_data->critical_start = data->critical_start; | |
672 | max_data->critical_end = data->critical_end; | |
5d4a9dba | 673 | |
1acaa1b2 | 674 | memcpy(max_data->comm, tsk->comm, TASK_COMM_LEN); |
8248ac05 SR |
675 | max_data->pid = tsk->pid; |
676 | max_data->uid = task_uid(tsk); | |
677 | max_data->nice = tsk->static_prio - 20 - MAX_RT_PRIO; | |
678 | max_data->policy = tsk->policy; | |
679 | max_data->rt_priority = tsk->rt_priority; | |
5d4a9dba SR |
680 | |
681 | /* record this tasks comm */ | |
682 | tracing_record_cmdline(tsk); | |
683 | } | |
684 | ||
4fcdae83 SR |
685 | /** |
686 | * update_max_tr - snapshot all trace buffers from global_trace to max_tr | |
687 | * @tr: tracer | |
688 | * @tsk: the task with the latency | |
689 | * @cpu: The cpu that initiated the trace. | |
690 | * | |
691 | * Flip the buffers between the @tr and the max_tr and record information | |
692 | * about which task was the cause of this latency. | |
693 | */ | |
e309b41d | 694 | void |
bc0c38d1 SR |
695 | update_max_tr(struct trace_array *tr, struct task_struct *tsk, int cpu) |
696 | { | |
3928a8a2 | 697 | struct ring_buffer *buf = tr->buffer; |
bc0c38d1 | 698 | |
b8de7bd1 SR |
699 | if (trace_stop_count) |
700 | return; | |
701 | ||
4c11d7ae | 702 | WARN_ON_ONCE(!irqs_disabled()); |
ef710e10 KM |
703 | if (!current_trace->use_max_tr) { |
704 | WARN_ON_ONCE(1); | |
705 | return; | |
706 | } | |
0199c4e6 | 707 | arch_spin_lock(&ftrace_max_lock); |
3928a8a2 SR |
708 | |
709 | tr->buffer = max_tr.buffer; | |
710 | max_tr.buffer = buf; | |
711 | ||
bc0c38d1 | 712 | __update_max_tr(tr, tsk, cpu); |
0199c4e6 | 713 | arch_spin_unlock(&ftrace_max_lock); |
bc0c38d1 SR |
714 | } |
715 | ||
716 | /** | |
717 | * update_max_tr_single - only copy one trace over, and reset the rest | |
718 | * @tr - tracer | |
719 | * @tsk - task with the latency | |
720 | * @cpu - the cpu of the buffer to copy. | |
4fcdae83 SR |
721 | * |
722 | * Flip the trace of a single CPU buffer between the @tr and the max_tr. | |
bc0c38d1 | 723 | */ |
e309b41d | 724 | void |
bc0c38d1 SR |
725 | update_max_tr_single(struct trace_array *tr, struct task_struct *tsk, int cpu) |
726 | { | |
3928a8a2 | 727 | int ret; |
bc0c38d1 | 728 | |
b8de7bd1 SR |
729 | if (trace_stop_count) |
730 | return; | |
731 | ||
4c11d7ae | 732 | WARN_ON_ONCE(!irqs_disabled()); |
ef710e10 KM |
733 | if (!current_trace->use_max_tr) { |
734 | WARN_ON_ONCE(1); | |
735 | return; | |
736 | } | |
737 | ||
0199c4e6 | 738 | arch_spin_lock(&ftrace_max_lock); |
bc0c38d1 | 739 | |
3928a8a2 SR |
740 | ret = ring_buffer_swap_cpu(max_tr.buffer, tr->buffer, cpu); |
741 | ||
e8165dbb SR |
742 | if (ret == -EBUSY) { |
743 | /* | |
744 | * We failed to swap the buffer due to a commit taking | |
745 | * place on this CPU. We fail to record, but we reset | |
746 | * the max trace buffer (no one writes directly to it) | |
747 | * and flag that it failed. | |
748 | */ | |
749 | trace_array_printk(&max_tr, _THIS_IP_, | |
750 | "Failed to swap buffers due to commit in progress\n"); | |
751 | } | |
752 | ||
e8165dbb | 753 | WARN_ON_ONCE(ret && ret != -EAGAIN && ret != -EBUSY); |
bc0c38d1 SR |
754 | |
755 | __update_max_tr(tr, tsk, cpu); | |
0199c4e6 | 756 | arch_spin_unlock(&ftrace_max_lock); |
bc0c38d1 | 757 | } |
5d4a9dba | 758 | #endif /* CONFIG_TRACER_MAX_TRACE */ |
bc0c38d1 | 759 | |
4fcdae83 SR |
760 | /** |
761 | * register_tracer - register a tracer with the ftrace system. | |
762 | * @type - the plugin for the tracer | |
763 | * | |
764 | * Register a new plugin tracer. | |
765 | */ | |
bc0c38d1 SR |
766 | int register_tracer(struct tracer *type) |
767 | { | |
768 | struct tracer *t; | |
bc0c38d1 SR |
769 | int ret = 0; |
770 | ||
771 | if (!type->name) { | |
772 | pr_info("Tracer must have a name\n"); | |
773 | return -1; | |
774 | } | |
775 | ||
24a461d5 | 776 | if (strlen(type->name) >= MAX_TRACER_SIZE) { |
ee6c2c1b LZ |
777 | pr_info("Tracer has a name longer than %d\n", MAX_TRACER_SIZE); |
778 | return -1; | |
779 | } | |
780 | ||
bc0c38d1 | 781 | mutex_lock(&trace_types_lock); |
86fa2f60 | 782 | |
8e1b82e0 FW |
783 | tracing_selftest_running = true; |
784 | ||
bc0c38d1 SR |
785 | for (t = trace_types; t; t = t->next) { |
786 | if (strcmp(type->name, t->name) == 0) { | |
787 | /* already found */ | |
ee6c2c1b | 788 | pr_info("Tracer %s already registered\n", |
bc0c38d1 SR |
789 | type->name); |
790 | ret = -1; | |
791 | goto out; | |
792 | } | |
793 | } | |
794 | ||
adf9f195 FW |
795 | if (!type->set_flag) |
796 | type->set_flag = &dummy_set_flag; | |
797 | if (!type->flags) | |
798 | type->flags = &dummy_tracer_flags; | |
799 | else | |
800 | if (!type->flags->opts) | |
801 | type->flags->opts = dummy_tracer_opt; | |
6eaaa5d5 FW |
802 | if (!type->wait_pipe) |
803 | type->wait_pipe = default_wait_pipe; | |
804 | ||
adf9f195 | 805 | |
60a11774 | 806 | #ifdef CONFIG_FTRACE_STARTUP_TEST |
b2821ae6 | 807 | if (type->selftest && !tracing_selftest_disabled) { |
60a11774 | 808 | struct tracer *saved_tracer = current_trace; |
60a11774 | 809 | struct trace_array *tr = &global_trace; |
ff32504f | 810 | |
60a11774 SR |
811 | /* |
812 | * Run a selftest on this tracer. | |
813 | * Here we reset the trace buffer, and set the current | |
814 | * tracer to be this tracer. The tracer can then run some | |
815 | * internal tracing to verify that everything is in order. | |
816 | * If we fail, we do not register this tracer. | |
817 | */ | |
76f0d073 | 818 | tracing_reset_online_cpus(tr); |
86fa2f60 | 819 | |
60a11774 | 820 | current_trace = type; |
4a0b1665 SR |
821 | |
822 | /* If we expanded the buffers, make sure the max is expanded too */ | |
823 | if (ring_buffer_expanded && type->use_max_tr) | |
438ced17 VN |
824 | ring_buffer_resize(max_tr.buffer, trace_buf_size, |
825 | RING_BUFFER_ALL_CPUS); | |
4a0b1665 | 826 | |
60a11774 SR |
827 | /* the test is responsible for initializing and enabling */ |
828 | pr_info("Testing tracer %s: ", type->name); | |
829 | ret = type->selftest(type, tr); | |
830 | /* the test is responsible for resetting too */ | |
831 | current_trace = saved_tracer; | |
60a11774 SR |
832 | if (ret) { |
833 | printk(KERN_CONT "FAILED!\n"); | |
0be61ebc SR |
834 | /* Add the warning after printing 'FAILED' */ |
835 | WARN_ON(1); | |
60a11774 SR |
836 | goto out; |
837 | } | |
1d4db00a | 838 | /* Only reset on passing, to avoid touching corrupted buffers */ |
76f0d073 | 839 | tracing_reset_online_cpus(tr); |
86fa2f60 | 840 | |
4a0b1665 SR |
841 | /* Shrink the max buffer again */ |
842 | if (ring_buffer_expanded && type->use_max_tr) | |
438ced17 VN |
843 | ring_buffer_resize(max_tr.buffer, 1, |
844 | RING_BUFFER_ALL_CPUS); | |
4a0b1665 | 845 | |
60a11774 SR |
846 | printk(KERN_CONT "PASSED\n"); |
847 | } | |
848 | #endif | |
849 | ||
bc0c38d1 SR |
850 | type->next = trace_types; |
851 | trace_types = type; | |
60a11774 | 852 | |
bc0c38d1 | 853 | out: |
8e1b82e0 | 854 | tracing_selftest_running = false; |
bc0c38d1 SR |
855 | mutex_unlock(&trace_types_lock); |
856 | ||
dac74940 SR |
857 | if (ret || !default_bootup_tracer) |
858 | goto out_unlock; | |
859 | ||
ee6c2c1b | 860 | if (strncmp(default_bootup_tracer, type->name, MAX_TRACER_SIZE)) |
dac74940 SR |
861 | goto out_unlock; |
862 | ||
863 | printk(KERN_INFO "Starting tracer '%s'\n", type->name); | |
864 | /* Do we want this tracer to start on bootup? */ | |
865 | tracing_set_tracer(type->name); | |
866 | default_bootup_tracer = NULL; | |
867 | /* disable other selftests, since this will break it. */ | |
868 | tracing_selftest_disabled = 1; | |
b2821ae6 | 869 | #ifdef CONFIG_FTRACE_STARTUP_TEST |
dac74940 SR |
870 | printk(KERN_INFO "Disabling FTRACE selftests due to running tracer '%s'\n", |
871 | type->name); | |
b2821ae6 | 872 | #endif |
b2821ae6 | 873 | |
dac74940 | 874 | out_unlock: |
bc0c38d1 SR |
875 | return ret; |
876 | } | |
877 | ||
878 | void unregister_tracer(struct tracer *type) | |
879 | { | |
880 | struct tracer **t; | |
bc0c38d1 SR |
881 | |
882 | mutex_lock(&trace_types_lock); | |
883 | for (t = &trace_types; *t; t = &(*t)->next) { | |
884 | if (*t == type) | |
885 | goto found; | |
886 | } | |
ee6c2c1b | 887 | pr_info("Tracer %s not registered\n", type->name); |
bc0c38d1 SR |
888 | goto out; |
889 | ||
890 | found: | |
891 | *t = (*t)->next; | |
b5db03c4 ACM |
892 | |
893 | if (type == current_trace && tracer_enabled) { | |
894 | tracer_enabled = 0; | |
895 | tracing_stop(); | |
896 | if (current_trace->stop) | |
897 | current_trace->stop(&global_trace); | |
898 | current_trace = &nop_trace; | |
899 | } | |
ee6c2c1b | 900 | out: |
bc0c38d1 SR |
901 | mutex_unlock(&trace_types_lock); |
902 | } | |
903 | ||
f633903a SR |
904 | void tracing_reset(struct trace_array *tr, int cpu) |
905 | { | |
906 | struct ring_buffer *buffer = tr->buffer; | |
907 | ||
908 | ring_buffer_record_disable(buffer); | |
909 | ||
910 | /* Make sure all commits have finished */ | |
911 | synchronize_sched(); | |
68179686 | 912 | ring_buffer_reset_cpu(buffer, cpu); |
f633903a SR |
913 | |
914 | ring_buffer_record_enable(buffer); | |
915 | } | |
916 | ||
213cc060 PE |
917 | void tracing_reset_online_cpus(struct trace_array *tr) |
918 | { | |
621968cd | 919 | struct ring_buffer *buffer = tr->buffer; |
213cc060 PE |
920 | int cpu; |
921 | ||
621968cd SR |
922 | ring_buffer_record_disable(buffer); |
923 | ||
924 | /* Make sure all commits have finished */ | |
925 | synchronize_sched(); | |
926 | ||
213cc060 PE |
927 | tr->time_start = ftrace_now(tr->cpu); |
928 | ||
929 | for_each_online_cpu(cpu) | |
68179686 | 930 | ring_buffer_reset_cpu(buffer, cpu); |
621968cd SR |
931 | |
932 | ring_buffer_record_enable(buffer); | |
213cc060 PE |
933 | } |
934 | ||
9456f0fa SR |
935 | void tracing_reset_current(int cpu) |
936 | { | |
937 | tracing_reset(&global_trace, cpu); | |
938 | } | |
939 | ||
940 | void tracing_reset_current_online_cpus(void) | |
941 | { | |
942 | tracing_reset_online_cpus(&global_trace); | |
943 | } | |
944 | ||
bc0c38d1 | 945 | #define SAVED_CMDLINES 128 |
2c7eea4c | 946 | #define NO_CMDLINE_MAP UINT_MAX |
bc0c38d1 SR |
947 | static unsigned map_pid_to_cmdline[PID_MAX_DEFAULT+1]; |
948 | static unsigned map_cmdline_to_pid[SAVED_CMDLINES]; | |
949 | static char saved_cmdlines[SAVED_CMDLINES][TASK_COMM_LEN]; | |
950 | static int cmdline_idx; | |
edc35bd7 | 951 | static arch_spinlock_t trace_cmdline_lock = __ARCH_SPIN_LOCK_UNLOCKED; |
25b0b44a | 952 | |
25b0b44a | 953 | /* temporary disable recording */ |
4fd27358 | 954 | static atomic_t trace_record_cmdline_disabled __read_mostly; |
bc0c38d1 SR |
955 | |
956 | static void trace_init_cmdlines(void) | |
957 | { | |
2c7eea4c TG |
958 | memset(&map_pid_to_cmdline, NO_CMDLINE_MAP, sizeof(map_pid_to_cmdline)); |
959 | memset(&map_cmdline_to_pid, NO_CMDLINE_MAP, sizeof(map_cmdline_to_pid)); | |
bc0c38d1 SR |
960 | cmdline_idx = 0; |
961 | } | |
962 | ||
b5130b1e CE |
963 | int is_tracing_stopped(void) |
964 | { | |
965 | return trace_stop_count; | |
966 | } | |
967 | ||
69bb54ec SR |
968 | /** |
969 | * ftrace_off_permanent - disable all ftrace code permanently | |
970 | * | |
971 | * This should only be called when a serious anomally has | |
972 | * been detected. This will turn off the function tracing, | |
973 | * ring buffers, and other tracing utilites. It takes no | |
974 | * locks and can be called from any context. | |
975 | */ | |
976 | void ftrace_off_permanent(void) | |
977 | { | |
978 | tracing_disabled = 1; | |
979 | ftrace_stop(); | |
980 | tracing_off_permanent(); | |
981 | } | |
982 | ||
0f048701 SR |
983 | /** |
984 | * tracing_start - quick start of the tracer | |
985 | * | |
986 | * If tracing is enabled but was stopped by tracing_stop, | |
987 | * this will start the tracer back up. | |
988 | */ | |
989 | void tracing_start(void) | |
990 | { | |
991 | struct ring_buffer *buffer; | |
992 | unsigned long flags; | |
993 | ||
994 | if (tracing_disabled) | |
995 | return; | |
996 | ||
5389f6fa | 997 | raw_spin_lock_irqsave(&tracing_start_lock, flags); |
b06a8301 SR |
998 | if (--trace_stop_count) { |
999 | if (trace_stop_count < 0) { | |
1000 | /* Someone screwed up their debugging */ | |
1001 | WARN_ON_ONCE(1); | |
1002 | trace_stop_count = 0; | |
1003 | } | |
0f048701 SR |
1004 | goto out; |
1005 | } | |
1006 | ||
a2f80714 SR |
1007 | /* Prevent the buffers from switching */ |
1008 | arch_spin_lock(&ftrace_max_lock); | |
0f048701 SR |
1009 | |
1010 | buffer = global_trace.buffer; | |
1011 | if (buffer) | |
1012 | ring_buffer_record_enable(buffer); | |
1013 | ||
1014 | buffer = max_tr.buffer; | |
1015 | if (buffer) | |
1016 | ring_buffer_record_enable(buffer); | |
1017 | ||
a2f80714 SR |
1018 | arch_spin_unlock(&ftrace_max_lock); |
1019 | ||
0f048701 SR |
1020 | ftrace_start(); |
1021 | out: | |
5389f6fa | 1022 | raw_spin_unlock_irqrestore(&tracing_start_lock, flags); |
0f048701 SR |
1023 | } |
1024 | ||
1025 | /** | |
1026 | * tracing_stop - quick stop of the tracer | |
1027 | * | |
1028 | * Light weight way to stop tracing. Use in conjunction with | |
1029 | * tracing_start. | |
1030 | */ | |
1031 | void tracing_stop(void) | |
1032 | { | |
1033 | struct ring_buffer *buffer; | |
1034 | unsigned long flags; | |
1035 | ||
1036 | ftrace_stop(); | |
5389f6fa | 1037 | raw_spin_lock_irqsave(&tracing_start_lock, flags); |
0f048701 SR |
1038 | if (trace_stop_count++) |
1039 | goto out; | |
1040 | ||
a2f80714 SR |
1041 | /* Prevent the buffers from switching */ |
1042 | arch_spin_lock(&ftrace_max_lock); | |
1043 | ||
0f048701 SR |
1044 | buffer = global_trace.buffer; |
1045 | if (buffer) | |
1046 | ring_buffer_record_disable(buffer); | |
1047 | ||
1048 | buffer = max_tr.buffer; | |
1049 | if (buffer) | |
1050 | ring_buffer_record_disable(buffer); | |
1051 | ||
a2f80714 SR |
1052 | arch_spin_unlock(&ftrace_max_lock); |
1053 | ||
0f048701 | 1054 | out: |
5389f6fa | 1055 | raw_spin_unlock_irqrestore(&tracing_start_lock, flags); |
0f048701 SR |
1056 | } |
1057 | ||
e309b41d | 1058 | void trace_stop_cmdline_recording(void); |
bc0c38d1 | 1059 | |
e309b41d | 1060 | static void trace_save_cmdline(struct task_struct *tsk) |
bc0c38d1 | 1061 | { |
a635cf04 | 1062 | unsigned pid, idx; |
bc0c38d1 SR |
1063 | |
1064 | if (!tsk->pid || unlikely(tsk->pid > PID_MAX_DEFAULT)) | |
1065 | return; | |
1066 | ||
1067 | /* | |
1068 | * It's not the end of the world if we don't get | |
1069 | * the lock, but we also don't want to spin | |
1070 | * nor do we want to disable interrupts, | |
1071 | * so if we miss here, then better luck next time. | |
1072 | */ | |
0199c4e6 | 1073 | if (!arch_spin_trylock(&trace_cmdline_lock)) |
bc0c38d1 SR |
1074 | return; |
1075 | ||
1076 | idx = map_pid_to_cmdline[tsk->pid]; | |
2c7eea4c | 1077 | if (idx == NO_CMDLINE_MAP) { |
bc0c38d1 SR |
1078 | idx = (cmdline_idx + 1) % SAVED_CMDLINES; |
1079 | ||
a635cf04 CE |
1080 | /* |
1081 | * Check whether the cmdline buffer at idx has a pid | |
1082 | * mapped. We are going to overwrite that entry so we | |
1083 | * need to clear the map_pid_to_cmdline. Otherwise we | |
1084 | * would read the new comm for the old pid. | |
1085 | */ | |
1086 | pid = map_cmdline_to_pid[idx]; | |
1087 | if (pid != NO_CMDLINE_MAP) | |
1088 | map_pid_to_cmdline[pid] = NO_CMDLINE_MAP; | |
bc0c38d1 | 1089 | |
a635cf04 | 1090 | map_cmdline_to_pid[idx] = tsk->pid; |
bc0c38d1 SR |
1091 | map_pid_to_cmdline[tsk->pid] = idx; |
1092 | ||
1093 | cmdline_idx = idx; | |
1094 | } | |
1095 | ||
1096 | memcpy(&saved_cmdlines[idx], tsk->comm, TASK_COMM_LEN); | |
1097 | ||
0199c4e6 | 1098 | arch_spin_unlock(&trace_cmdline_lock); |
bc0c38d1 SR |
1099 | } |
1100 | ||
4ca53085 | 1101 | void trace_find_cmdline(int pid, char comm[]) |
bc0c38d1 | 1102 | { |
bc0c38d1 SR |
1103 | unsigned map; |
1104 | ||
4ca53085 SR |
1105 | if (!pid) { |
1106 | strcpy(comm, "<idle>"); | |
1107 | return; | |
1108 | } | |
bc0c38d1 | 1109 | |
74bf4076 SR |
1110 | if (WARN_ON_ONCE(pid < 0)) { |
1111 | strcpy(comm, "<XXX>"); | |
1112 | return; | |
1113 | } | |
1114 | ||
4ca53085 SR |
1115 | if (pid > PID_MAX_DEFAULT) { |
1116 | strcpy(comm, "<...>"); | |
1117 | return; | |
1118 | } | |
bc0c38d1 | 1119 | |
5b6045a9 | 1120 | preempt_disable(); |
0199c4e6 | 1121 | arch_spin_lock(&trace_cmdline_lock); |
bc0c38d1 | 1122 | map = map_pid_to_cmdline[pid]; |
50d88758 TG |
1123 | if (map != NO_CMDLINE_MAP) |
1124 | strcpy(comm, saved_cmdlines[map]); | |
1125 | else | |
1126 | strcpy(comm, "<...>"); | |
bc0c38d1 | 1127 | |
0199c4e6 | 1128 | arch_spin_unlock(&trace_cmdline_lock); |
5b6045a9 | 1129 | preempt_enable(); |
bc0c38d1 SR |
1130 | } |
1131 | ||
e309b41d | 1132 | void tracing_record_cmdline(struct task_struct *tsk) |
bc0c38d1 | 1133 | { |
18aecd36 TG |
1134 | if (atomic_read(&trace_record_cmdline_disabled) || !tracer_enabled || |
1135 | !tracing_is_on()) | |
bc0c38d1 SR |
1136 | return; |
1137 | ||
1138 | trace_save_cmdline(tsk); | |
1139 | } | |
1140 | ||
45dcd8b8 | 1141 | void |
38697053 SR |
1142 | tracing_generic_entry_update(struct trace_entry *entry, unsigned long flags, |
1143 | int pc) | |
bc0c38d1 SR |
1144 | { |
1145 | struct task_struct *tsk = current; | |
bc0c38d1 | 1146 | |
777e208d SR |
1147 | entry->preempt_count = pc & 0xff; |
1148 | entry->pid = (tsk) ? tsk->pid : 0; | |
a3a4a5ac | 1149 | entry->padding = 0; |
777e208d | 1150 | entry->flags = |
9244489a | 1151 | #ifdef CONFIG_TRACE_IRQFLAGS_SUPPORT |
2e2ca155 | 1152 | (irqs_disabled_flags(flags) ? TRACE_FLAG_IRQS_OFF : 0) | |
9244489a SR |
1153 | #else |
1154 | TRACE_FLAG_IRQS_NOSUPPORT | | |
1155 | #endif | |
bc0c38d1 SR |
1156 | ((pc & HARDIRQ_MASK) ? TRACE_FLAG_HARDIRQ : 0) | |
1157 | ((pc & SOFTIRQ_MASK) ? TRACE_FLAG_SOFTIRQ : 0) | | |
1158 | (need_resched() ? TRACE_FLAG_NEED_RESCHED : 0); | |
1159 | } | |
f413cdb8 | 1160 | EXPORT_SYMBOL_GPL(tracing_generic_entry_update); |
bc0c38d1 | 1161 | |
e77405ad SR |
1162 | struct ring_buffer_event * |
1163 | trace_buffer_lock_reserve(struct ring_buffer *buffer, | |
1164 | int type, | |
1165 | unsigned long len, | |
1166 | unsigned long flags, int pc) | |
51a763dd ACM |
1167 | { |
1168 | struct ring_buffer_event *event; | |
1169 | ||
e77405ad | 1170 | event = ring_buffer_lock_reserve(buffer, len); |
51a763dd ACM |
1171 | if (event != NULL) { |
1172 | struct trace_entry *ent = ring_buffer_event_data(event); | |
1173 | ||
1174 | tracing_generic_entry_update(ent, flags, pc); | |
1175 | ent->type = type; | |
1176 | } | |
1177 | ||
1178 | return event; | |
1179 | } | |
51a763dd | 1180 | |
e77405ad SR |
1181 | static inline void |
1182 | __trace_buffer_unlock_commit(struct ring_buffer *buffer, | |
1183 | struct ring_buffer_event *event, | |
1184 | unsigned long flags, int pc, | |
1185 | int wake) | |
51a763dd | 1186 | { |
e77405ad | 1187 | ring_buffer_unlock_commit(buffer, event); |
51a763dd | 1188 | |
e77405ad SR |
1189 | ftrace_trace_stack(buffer, flags, 6, pc); |
1190 | ftrace_trace_userstack(buffer, flags, pc); | |
07edf712 FW |
1191 | |
1192 | if (wake) | |
1193 | trace_wake_up(); | |
1194 | } | |
1195 | ||
e77405ad SR |
1196 | void trace_buffer_unlock_commit(struct ring_buffer *buffer, |
1197 | struct ring_buffer_event *event, | |
1198 | unsigned long flags, int pc) | |
07edf712 | 1199 | { |
e77405ad | 1200 | __trace_buffer_unlock_commit(buffer, event, flags, pc, 1); |
51a763dd ACM |
1201 | } |
1202 | ||
ef5580d0 | 1203 | struct ring_buffer_event * |
e77405ad SR |
1204 | trace_current_buffer_lock_reserve(struct ring_buffer **current_rb, |
1205 | int type, unsigned long len, | |
ef5580d0 SR |
1206 | unsigned long flags, int pc) |
1207 | { | |
e77405ad SR |
1208 | *current_rb = global_trace.buffer; |
1209 | return trace_buffer_lock_reserve(*current_rb, | |
ef5580d0 SR |
1210 | type, len, flags, pc); |
1211 | } | |
94487d6d | 1212 | EXPORT_SYMBOL_GPL(trace_current_buffer_lock_reserve); |
ef5580d0 | 1213 | |
e77405ad SR |
1214 | void trace_current_buffer_unlock_commit(struct ring_buffer *buffer, |
1215 | struct ring_buffer_event *event, | |
ef5580d0 SR |
1216 | unsigned long flags, int pc) |
1217 | { | |
e77405ad | 1218 | __trace_buffer_unlock_commit(buffer, event, flags, pc, 1); |
07edf712 | 1219 | } |
94487d6d | 1220 | EXPORT_SYMBOL_GPL(trace_current_buffer_unlock_commit); |
07edf712 | 1221 | |
e77405ad SR |
1222 | void trace_nowake_buffer_unlock_commit(struct ring_buffer *buffer, |
1223 | struct ring_buffer_event *event, | |
1224 | unsigned long flags, int pc) | |
07edf712 | 1225 | { |
e77405ad | 1226 | __trace_buffer_unlock_commit(buffer, event, flags, pc, 0); |
77d9f465 | 1227 | } |
94487d6d | 1228 | EXPORT_SYMBOL_GPL(trace_nowake_buffer_unlock_commit); |
77d9f465 | 1229 | |
1fd8df2c MH |
1230 | void trace_nowake_buffer_unlock_commit_regs(struct ring_buffer *buffer, |
1231 | struct ring_buffer_event *event, | |
1232 | unsigned long flags, int pc, | |
1233 | struct pt_regs *regs) | |
1234 | { | |
1235 | ring_buffer_unlock_commit(buffer, event); | |
1236 | ||
1237 | ftrace_trace_stack_regs(buffer, flags, 0, pc, regs); | |
1238 | ftrace_trace_userstack(buffer, flags, pc); | |
1239 | } | |
1240 | EXPORT_SYMBOL_GPL(trace_nowake_buffer_unlock_commit_regs); | |
1241 | ||
e77405ad SR |
1242 | void trace_current_buffer_discard_commit(struct ring_buffer *buffer, |
1243 | struct ring_buffer_event *event) | |
77d9f465 | 1244 | { |
e77405ad | 1245 | ring_buffer_discard_commit(buffer, event); |
ef5580d0 | 1246 | } |
12acd473 | 1247 | EXPORT_SYMBOL_GPL(trace_current_buffer_discard_commit); |
ef5580d0 | 1248 | |
e309b41d | 1249 | void |
7be42151 | 1250 | trace_function(struct trace_array *tr, |
38697053 SR |
1251 | unsigned long ip, unsigned long parent_ip, unsigned long flags, |
1252 | int pc) | |
bc0c38d1 | 1253 | { |
e1112b4d | 1254 | struct ftrace_event_call *call = &event_function; |
e77405ad | 1255 | struct ring_buffer *buffer = tr->buffer; |
3928a8a2 | 1256 | struct ring_buffer_event *event; |
777e208d | 1257 | struct ftrace_entry *entry; |
bc0c38d1 | 1258 | |
d769041f | 1259 | /* If we are reading the ring buffer, don't trace */ |
dd17c8f7 | 1260 | if (unlikely(__this_cpu_read(ftrace_cpu_disabled))) |
d769041f SR |
1261 | return; |
1262 | ||
e77405ad | 1263 | event = trace_buffer_lock_reserve(buffer, TRACE_FN, sizeof(*entry), |
51a763dd | 1264 | flags, pc); |
3928a8a2 SR |
1265 | if (!event) |
1266 | return; | |
1267 | entry = ring_buffer_event_data(event); | |
777e208d SR |
1268 | entry->ip = ip; |
1269 | entry->parent_ip = parent_ip; | |
e1112b4d | 1270 | |
e77405ad SR |
1271 | if (!filter_check_discard(call, entry, buffer, event)) |
1272 | ring_buffer_unlock_commit(buffer, event); | |
bc0c38d1 SR |
1273 | } |
1274 | ||
e309b41d | 1275 | void |
2e0f5761 | 1276 | ftrace(struct trace_array *tr, struct trace_array_cpu *data, |
38697053 SR |
1277 | unsigned long ip, unsigned long parent_ip, unsigned long flags, |
1278 | int pc) | |
2e0f5761 IM |
1279 | { |
1280 | if (likely(!atomic_read(&data->disabled))) | |
7be42151 | 1281 | trace_function(tr, ip, parent_ip, flags, pc); |
2e0f5761 IM |
1282 | } |
1283 | ||
c0a0d0d3 | 1284 | #ifdef CONFIG_STACKTRACE |
4a9bd3f1 SR |
1285 | |
1286 | #define FTRACE_STACK_MAX_ENTRIES (PAGE_SIZE / sizeof(unsigned long)) | |
1287 | struct ftrace_stack { | |
1288 | unsigned long calls[FTRACE_STACK_MAX_ENTRIES]; | |
1289 | }; | |
1290 | ||
1291 | static DEFINE_PER_CPU(struct ftrace_stack, ftrace_stack); | |
1292 | static DEFINE_PER_CPU(int, ftrace_stack_reserve); | |
1293 | ||
e77405ad | 1294 | static void __ftrace_trace_stack(struct ring_buffer *buffer, |
53614991 | 1295 | unsigned long flags, |
1fd8df2c | 1296 | int skip, int pc, struct pt_regs *regs) |
86387f7e | 1297 | { |
e1112b4d | 1298 | struct ftrace_event_call *call = &event_kernel_stack; |
3928a8a2 | 1299 | struct ring_buffer_event *event; |
777e208d | 1300 | struct stack_entry *entry; |
86387f7e | 1301 | struct stack_trace trace; |
4a9bd3f1 SR |
1302 | int use_stack; |
1303 | int size = FTRACE_STACK_ENTRIES; | |
1304 | ||
1305 | trace.nr_entries = 0; | |
1306 | trace.skip = skip; | |
1307 | ||
1308 | /* | |
1309 | * Since events can happen in NMIs there's no safe way to | |
1310 | * use the per cpu ftrace_stacks. We reserve it and if an interrupt | |
1311 | * or NMI comes in, it will just have to use the default | |
1312 | * FTRACE_STACK_SIZE. | |
1313 | */ | |
1314 | preempt_disable_notrace(); | |
1315 | ||
1316 | use_stack = ++__get_cpu_var(ftrace_stack_reserve); | |
1317 | /* | |
1318 | * We don't need any atomic variables, just a barrier. | |
1319 | * If an interrupt comes in, we don't care, because it would | |
1320 | * have exited and put the counter back to what we want. | |
1321 | * We just need a barrier to keep gcc from moving things | |
1322 | * around. | |
1323 | */ | |
1324 | barrier(); | |
1325 | if (use_stack == 1) { | |
1326 | trace.entries = &__get_cpu_var(ftrace_stack).calls[0]; | |
1327 | trace.max_entries = FTRACE_STACK_MAX_ENTRIES; | |
1328 | ||
1329 | if (regs) | |
1330 | save_stack_trace_regs(regs, &trace); | |
1331 | else | |
1332 | save_stack_trace(&trace); | |
1333 | ||
1334 | if (trace.nr_entries > size) | |
1335 | size = trace.nr_entries; | |
1336 | } else | |
1337 | /* From now on, use_stack is a boolean */ | |
1338 | use_stack = 0; | |
1339 | ||
1340 | size *= sizeof(unsigned long); | |
86387f7e | 1341 | |
e77405ad | 1342 | event = trace_buffer_lock_reserve(buffer, TRACE_STACK, |
4a9bd3f1 | 1343 | sizeof(*entry) + size, flags, pc); |
3928a8a2 | 1344 | if (!event) |
4a9bd3f1 SR |
1345 | goto out; |
1346 | entry = ring_buffer_event_data(event); | |
86387f7e | 1347 | |
4a9bd3f1 SR |
1348 | memset(&entry->caller, 0, size); |
1349 | ||
1350 | if (use_stack) | |
1351 | memcpy(&entry->caller, trace.entries, | |
1352 | trace.nr_entries * sizeof(unsigned long)); | |
1353 | else { | |
1354 | trace.max_entries = FTRACE_STACK_ENTRIES; | |
1355 | trace.entries = entry->caller; | |
1356 | if (regs) | |
1357 | save_stack_trace_regs(regs, &trace); | |
1358 | else | |
1359 | save_stack_trace(&trace); | |
1360 | } | |
1361 | ||
1362 | entry->size = trace.nr_entries; | |
86387f7e | 1363 | |
e77405ad SR |
1364 | if (!filter_check_discard(call, entry, buffer, event)) |
1365 | ring_buffer_unlock_commit(buffer, event); | |
4a9bd3f1 SR |
1366 | |
1367 | out: | |
1368 | /* Again, don't let gcc optimize things here */ | |
1369 | barrier(); | |
1370 | __get_cpu_var(ftrace_stack_reserve)--; | |
1371 | preempt_enable_notrace(); | |
1372 | ||
f0a920d5 IM |
1373 | } |
1374 | ||
1fd8df2c MH |
1375 | void ftrace_trace_stack_regs(struct ring_buffer *buffer, unsigned long flags, |
1376 | int skip, int pc, struct pt_regs *regs) | |
1377 | { | |
1378 | if (!(trace_flags & TRACE_ITER_STACKTRACE)) | |
1379 | return; | |
1380 | ||
1381 | __ftrace_trace_stack(buffer, flags, skip, pc, regs); | |
1382 | } | |
1383 | ||
e77405ad SR |
1384 | void ftrace_trace_stack(struct ring_buffer *buffer, unsigned long flags, |
1385 | int skip, int pc) | |
53614991 SR |
1386 | { |
1387 | if (!(trace_flags & TRACE_ITER_STACKTRACE)) | |
1388 | return; | |
1389 | ||
1fd8df2c | 1390 | __ftrace_trace_stack(buffer, flags, skip, pc, NULL); |
53614991 SR |
1391 | } |
1392 | ||
c0a0d0d3 FW |
1393 | void __trace_stack(struct trace_array *tr, unsigned long flags, int skip, |
1394 | int pc) | |
38697053 | 1395 | { |
1fd8df2c | 1396 | __ftrace_trace_stack(tr->buffer, flags, skip, pc, NULL); |
38697053 SR |
1397 | } |
1398 | ||
03889384 SR |
1399 | /** |
1400 | * trace_dump_stack - record a stack back trace in the trace buffer | |
1401 | */ | |
1402 | void trace_dump_stack(void) | |
1403 | { | |
1404 | unsigned long flags; | |
1405 | ||
1406 | if (tracing_disabled || tracing_selftest_running) | |
e36c5458 | 1407 | return; |
03889384 SR |
1408 | |
1409 | local_save_flags(flags); | |
1410 | ||
1411 | /* skipping 3 traces, seems to get us at the caller of this function */ | |
1fd8df2c | 1412 | __ftrace_trace_stack(global_trace.buffer, flags, 3, preempt_count(), NULL); |
03889384 SR |
1413 | } |
1414 | ||
91e86e56 SR |
1415 | static DEFINE_PER_CPU(int, user_stack_count); |
1416 | ||
e77405ad SR |
1417 | void |
1418 | ftrace_trace_userstack(struct ring_buffer *buffer, unsigned long flags, int pc) | |
02b67518 | 1419 | { |
e1112b4d | 1420 | struct ftrace_event_call *call = &event_user_stack; |
8d7c6a96 | 1421 | struct ring_buffer_event *event; |
02b67518 TE |
1422 | struct userstack_entry *entry; |
1423 | struct stack_trace trace; | |
02b67518 TE |
1424 | |
1425 | if (!(trace_flags & TRACE_ITER_USERSTACKTRACE)) | |
1426 | return; | |
1427 | ||
b6345879 SR |
1428 | /* |
1429 | * NMIs can not handle page faults, even with fix ups. | |
1430 | * The save user stack can (and often does) fault. | |
1431 | */ | |
1432 | if (unlikely(in_nmi())) | |
1433 | return; | |
02b67518 | 1434 | |
91e86e56 SR |
1435 | /* |
1436 | * prevent recursion, since the user stack tracing may | |
1437 | * trigger other kernel events. | |
1438 | */ | |
1439 | preempt_disable(); | |
1440 | if (__this_cpu_read(user_stack_count)) | |
1441 | goto out; | |
1442 | ||
1443 | __this_cpu_inc(user_stack_count); | |
1444 | ||
e77405ad | 1445 | event = trace_buffer_lock_reserve(buffer, TRACE_USER_STACK, |
51a763dd | 1446 | sizeof(*entry), flags, pc); |
02b67518 | 1447 | if (!event) |
1dbd1951 | 1448 | goto out_drop_count; |
02b67518 | 1449 | entry = ring_buffer_event_data(event); |
02b67518 | 1450 | |
48659d31 | 1451 | entry->tgid = current->tgid; |
02b67518 TE |
1452 | memset(&entry->caller, 0, sizeof(entry->caller)); |
1453 | ||
1454 | trace.nr_entries = 0; | |
1455 | trace.max_entries = FTRACE_STACK_ENTRIES; | |
1456 | trace.skip = 0; | |
1457 | trace.entries = entry->caller; | |
1458 | ||
1459 | save_stack_trace_user(&trace); | |
e77405ad SR |
1460 | if (!filter_check_discard(call, entry, buffer, event)) |
1461 | ring_buffer_unlock_commit(buffer, event); | |
91e86e56 | 1462 | |
1dbd1951 | 1463 | out_drop_count: |
91e86e56 | 1464 | __this_cpu_dec(user_stack_count); |
91e86e56 SR |
1465 | out: |
1466 | preempt_enable(); | |
02b67518 TE |
1467 | } |
1468 | ||
4fd27358 HE |
1469 | #ifdef UNUSED |
1470 | static void __trace_userstack(struct trace_array *tr, unsigned long flags) | |
02b67518 | 1471 | { |
7be42151 | 1472 | ftrace_trace_userstack(tr, flags, preempt_count()); |
02b67518 | 1473 | } |
4fd27358 | 1474 | #endif /* UNUSED */ |
02b67518 | 1475 | |
c0a0d0d3 FW |
1476 | #endif /* CONFIG_STACKTRACE */ |
1477 | ||
07d777fe SR |
1478 | /* created for use with alloc_percpu */ |
1479 | struct trace_buffer_struct { | |
1480 | char buffer[TRACE_BUF_SIZE]; | |
1481 | }; | |
1482 | ||
1483 | static struct trace_buffer_struct *trace_percpu_buffer; | |
1484 | static struct trace_buffer_struct *trace_percpu_sirq_buffer; | |
1485 | static struct trace_buffer_struct *trace_percpu_irq_buffer; | |
1486 | static struct trace_buffer_struct *trace_percpu_nmi_buffer; | |
1487 | ||
1488 | /* | |
1489 | * The buffer used is dependent on the context. There is a per cpu | |
1490 | * buffer for normal context, softirq contex, hard irq context and | |
1491 | * for NMI context. Thise allows for lockless recording. | |
1492 | * | |
1493 | * Note, if the buffers failed to be allocated, then this returns NULL | |
1494 | */ | |
1495 | static char *get_trace_buf(void) | |
1496 | { | |
1497 | struct trace_buffer_struct *percpu_buffer; | |
1498 | struct trace_buffer_struct *buffer; | |
1499 | ||
1500 | /* | |
1501 | * If we have allocated per cpu buffers, then we do not | |
1502 | * need to do any locking. | |
1503 | */ | |
1504 | if (in_nmi()) | |
1505 | percpu_buffer = trace_percpu_nmi_buffer; | |
1506 | else if (in_irq()) | |
1507 | percpu_buffer = trace_percpu_irq_buffer; | |
1508 | else if (in_softirq()) | |
1509 | percpu_buffer = trace_percpu_sirq_buffer; | |
1510 | else | |
1511 | percpu_buffer = trace_percpu_buffer; | |
1512 | ||
1513 | if (!percpu_buffer) | |
1514 | return NULL; | |
1515 | ||
1516 | buffer = per_cpu_ptr(percpu_buffer, smp_processor_id()); | |
1517 | ||
1518 | return buffer->buffer; | |
1519 | } | |
1520 | ||
1521 | static int alloc_percpu_trace_buffer(void) | |
1522 | { | |
1523 | struct trace_buffer_struct *buffers; | |
1524 | struct trace_buffer_struct *sirq_buffers; | |
1525 | struct trace_buffer_struct *irq_buffers; | |
1526 | struct trace_buffer_struct *nmi_buffers; | |
1527 | ||
1528 | buffers = alloc_percpu(struct trace_buffer_struct); | |
1529 | if (!buffers) | |
1530 | goto err_warn; | |
1531 | ||
1532 | sirq_buffers = alloc_percpu(struct trace_buffer_struct); | |
1533 | if (!sirq_buffers) | |
1534 | goto err_sirq; | |
1535 | ||
1536 | irq_buffers = alloc_percpu(struct trace_buffer_struct); | |
1537 | if (!irq_buffers) | |
1538 | goto err_irq; | |
1539 | ||
1540 | nmi_buffers = alloc_percpu(struct trace_buffer_struct); | |
1541 | if (!nmi_buffers) | |
1542 | goto err_nmi; | |
1543 | ||
1544 | trace_percpu_buffer = buffers; | |
1545 | trace_percpu_sirq_buffer = sirq_buffers; | |
1546 | trace_percpu_irq_buffer = irq_buffers; | |
1547 | trace_percpu_nmi_buffer = nmi_buffers; | |
1548 | ||
1549 | return 0; | |
1550 | ||
1551 | err_nmi: | |
1552 | free_percpu(irq_buffers); | |
1553 | err_irq: | |
1554 | free_percpu(sirq_buffers); | |
1555 | err_sirq: | |
1556 | free_percpu(buffers); | |
1557 | err_warn: | |
1558 | WARN(1, "Could not allocate percpu trace_printk buffer"); | |
1559 | return -ENOMEM; | |
1560 | } | |
1561 | ||
1562 | void trace_printk_init_buffers(void) | |
1563 | { | |
1564 | static int buffers_allocated; | |
1565 | ||
1566 | if (buffers_allocated) | |
1567 | return; | |
1568 | ||
1569 | if (alloc_percpu_trace_buffer()) | |
1570 | return; | |
1571 | ||
1572 | pr_info("ftrace: Allocated trace_printk buffers\n"); | |
1573 | ||
b382ede6 SR |
1574 | /* Expand the buffers to set size */ |
1575 | tracing_update_buffers(); | |
1576 | ||
07d777fe SR |
1577 | buffers_allocated = 1; |
1578 | } | |
1579 | ||
769b0441 | 1580 | /** |
48ead020 | 1581 | * trace_vbprintk - write binary msg to tracing buffer |
769b0441 FW |
1582 | * |
1583 | */ | |
40ce74f1 | 1584 | int trace_vbprintk(unsigned long ip, const char *fmt, va_list args) |
769b0441 | 1585 | { |
e1112b4d | 1586 | struct ftrace_event_call *call = &event_bprint; |
769b0441 | 1587 | struct ring_buffer_event *event; |
e77405ad | 1588 | struct ring_buffer *buffer; |
769b0441 | 1589 | struct trace_array *tr = &global_trace; |
48ead020 | 1590 | struct bprint_entry *entry; |
769b0441 | 1591 | unsigned long flags; |
07d777fe SR |
1592 | char *tbuffer; |
1593 | int len = 0, size, pc; | |
769b0441 FW |
1594 | |
1595 | if (unlikely(tracing_selftest_running || tracing_disabled)) | |
1596 | return 0; | |
1597 | ||
1598 | /* Don't pollute graph traces with trace_vprintk internals */ | |
1599 | pause_graph_tracing(); | |
1600 | ||
1601 | pc = preempt_count(); | |
5168ae50 | 1602 | preempt_disable_notrace(); |
769b0441 | 1603 | |
07d777fe SR |
1604 | tbuffer = get_trace_buf(); |
1605 | if (!tbuffer) { | |
1606 | len = 0; | |
769b0441 | 1607 | goto out; |
07d777fe | 1608 | } |
769b0441 | 1609 | |
07d777fe | 1610 | len = vbin_printf((u32 *)tbuffer, TRACE_BUF_SIZE/sizeof(int), fmt, args); |
769b0441 | 1611 | |
07d777fe SR |
1612 | if (len > TRACE_BUF_SIZE/sizeof(int) || len < 0) |
1613 | goto out; | |
769b0441 | 1614 | |
07d777fe | 1615 | local_save_flags(flags); |
769b0441 | 1616 | size = sizeof(*entry) + sizeof(u32) * len; |
e77405ad SR |
1617 | buffer = tr->buffer; |
1618 | event = trace_buffer_lock_reserve(buffer, TRACE_BPRINT, size, | |
1619 | flags, pc); | |
769b0441 | 1620 | if (!event) |
07d777fe | 1621 | goto out; |
769b0441 FW |
1622 | entry = ring_buffer_event_data(event); |
1623 | entry->ip = ip; | |
769b0441 FW |
1624 | entry->fmt = fmt; |
1625 | ||
07d777fe | 1626 | memcpy(entry->buf, tbuffer, sizeof(u32) * len); |
d931369b | 1627 | if (!filter_check_discard(call, entry, buffer, event)) { |
e77405ad | 1628 | ring_buffer_unlock_commit(buffer, event); |
d931369b SR |
1629 | ftrace_trace_stack(buffer, flags, 6, pc); |
1630 | } | |
769b0441 | 1631 | |
769b0441 | 1632 | out: |
5168ae50 | 1633 | preempt_enable_notrace(); |
769b0441 FW |
1634 | unpause_graph_tracing(); |
1635 | ||
1636 | return len; | |
1637 | } | |
48ead020 FW |
1638 | EXPORT_SYMBOL_GPL(trace_vbprintk); |
1639 | ||
659372d3 SR |
1640 | int trace_array_printk(struct trace_array *tr, |
1641 | unsigned long ip, const char *fmt, ...) | |
1642 | { | |
1643 | int ret; | |
1644 | va_list ap; | |
1645 | ||
1646 | if (!(trace_flags & TRACE_ITER_PRINTK)) | |
1647 | return 0; | |
1648 | ||
1649 | va_start(ap, fmt); | |
1650 | ret = trace_array_vprintk(tr, ip, fmt, ap); | |
1651 | va_end(ap); | |
1652 | return ret; | |
1653 | } | |
1654 | ||
1655 | int trace_array_vprintk(struct trace_array *tr, | |
1656 | unsigned long ip, const char *fmt, va_list args) | |
48ead020 | 1657 | { |
e1112b4d | 1658 | struct ftrace_event_call *call = &event_print; |
48ead020 | 1659 | struct ring_buffer_event *event; |
e77405ad | 1660 | struct ring_buffer *buffer; |
07d777fe | 1661 | int len = 0, size, pc; |
48ead020 | 1662 | struct print_entry *entry; |
07d777fe SR |
1663 | unsigned long flags; |
1664 | char *tbuffer; | |
48ead020 FW |
1665 | |
1666 | if (tracing_disabled || tracing_selftest_running) | |
1667 | return 0; | |
1668 | ||
07d777fe SR |
1669 | /* Don't pollute graph traces with trace_vprintk internals */ |
1670 | pause_graph_tracing(); | |
1671 | ||
48ead020 FW |
1672 | pc = preempt_count(); |
1673 | preempt_disable_notrace(); | |
48ead020 | 1674 | |
07d777fe SR |
1675 | |
1676 | tbuffer = get_trace_buf(); | |
1677 | if (!tbuffer) { | |
1678 | len = 0; | |
48ead020 | 1679 | goto out; |
07d777fe | 1680 | } |
48ead020 | 1681 | |
07d777fe SR |
1682 | len = vsnprintf(tbuffer, TRACE_BUF_SIZE, fmt, args); |
1683 | if (len > TRACE_BUF_SIZE) | |
1684 | goto out; | |
48ead020 | 1685 | |
07d777fe | 1686 | local_save_flags(flags); |
48ead020 | 1687 | size = sizeof(*entry) + len + 1; |
e77405ad SR |
1688 | buffer = tr->buffer; |
1689 | event = trace_buffer_lock_reserve(buffer, TRACE_PRINT, size, | |
07d777fe | 1690 | flags, pc); |
48ead020 | 1691 | if (!event) |
07d777fe | 1692 | goto out; |
48ead020 | 1693 | entry = ring_buffer_event_data(event); |
c13d2f7c | 1694 | entry->ip = ip; |
48ead020 | 1695 | |
07d777fe | 1696 | memcpy(&entry->buf, tbuffer, len); |
c13d2f7c | 1697 | entry->buf[len] = '\0'; |
d931369b | 1698 | if (!filter_check_discard(call, entry, buffer, event)) { |
e77405ad | 1699 | ring_buffer_unlock_commit(buffer, event); |
07d777fe | 1700 | ftrace_trace_stack(buffer, flags, 6, pc); |
d931369b | 1701 | } |
48ead020 FW |
1702 | out: |
1703 | preempt_enable_notrace(); | |
07d777fe | 1704 | unpause_graph_tracing(); |
48ead020 FW |
1705 | |
1706 | return len; | |
1707 | } | |
659372d3 SR |
1708 | |
1709 | int trace_vprintk(unsigned long ip, const char *fmt, va_list args) | |
1710 | { | |
a813a159 | 1711 | return trace_array_vprintk(&global_trace, ip, fmt, args); |
659372d3 | 1712 | } |
769b0441 FW |
1713 | EXPORT_SYMBOL_GPL(trace_vprintk); |
1714 | ||
e2ac8ef5 | 1715 | static void trace_iterator_increment(struct trace_iterator *iter) |
5a90f577 | 1716 | { |
6d158a81 SR |
1717 | struct ring_buffer_iter *buf_iter = trace_buffer_iter(iter, iter->cpu); |
1718 | ||
5a90f577 | 1719 | iter->idx++; |
6d158a81 SR |
1720 | if (buf_iter) |
1721 | ring_buffer_read(buf_iter, NULL); | |
5a90f577 SR |
1722 | } |
1723 | ||
e309b41d | 1724 | static struct trace_entry * |
bc21b478 SR |
1725 | peek_next_entry(struct trace_iterator *iter, int cpu, u64 *ts, |
1726 | unsigned long *lost_events) | |
dd0e545f | 1727 | { |
3928a8a2 | 1728 | struct ring_buffer_event *event; |
6d158a81 | 1729 | struct ring_buffer_iter *buf_iter = trace_buffer_iter(iter, cpu); |
dd0e545f | 1730 | |
d769041f SR |
1731 | if (buf_iter) |
1732 | event = ring_buffer_iter_peek(buf_iter, ts); | |
1733 | else | |
bc21b478 SR |
1734 | event = ring_buffer_peek(iter->tr->buffer, cpu, ts, |
1735 | lost_events); | |
d769041f | 1736 | |
4a9bd3f1 SR |
1737 | if (event) { |
1738 | iter->ent_size = ring_buffer_event_length(event); | |
1739 | return ring_buffer_event_data(event); | |
1740 | } | |
1741 | iter->ent_size = 0; | |
1742 | return NULL; | |
dd0e545f | 1743 | } |
d769041f | 1744 | |
dd0e545f | 1745 | static struct trace_entry * |
bc21b478 SR |
1746 | __find_next_entry(struct trace_iterator *iter, int *ent_cpu, |
1747 | unsigned long *missing_events, u64 *ent_ts) | |
bc0c38d1 | 1748 | { |
3928a8a2 | 1749 | struct ring_buffer *buffer = iter->tr->buffer; |
bc0c38d1 | 1750 | struct trace_entry *ent, *next = NULL; |
aa27497c | 1751 | unsigned long lost_events = 0, next_lost = 0; |
b04cc6b1 | 1752 | int cpu_file = iter->cpu_file; |
3928a8a2 | 1753 | u64 next_ts = 0, ts; |
bc0c38d1 | 1754 | int next_cpu = -1; |
12b5da34 | 1755 | int next_size = 0; |
bc0c38d1 SR |
1756 | int cpu; |
1757 | ||
b04cc6b1 FW |
1758 | /* |
1759 | * If we are in a per_cpu trace file, don't bother by iterating over | |
1760 | * all cpu and peek directly. | |
1761 | */ | |
1762 | if (cpu_file > TRACE_PIPE_ALL_CPU) { | |
1763 | if (ring_buffer_empty_cpu(buffer, cpu_file)) | |
1764 | return NULL; | |
bc21b478 | 1765 | ent = peek_next_entry(iter, cpu_file, ent_ts, missing_events); |
b04cc6b1 FW |
1766 | if (ent_cpu) |
1767 | *ent_cpu = cpu_file; | |
1768 | ||
1769 | return ent; | |
1770 | } | |
1771 | ||
ab46428c | 1772 | for_each_tracing_cpu(cpu) { |
dd0e545f | 1773 | |
3928a8a2 SR |
1774 | if (ring_buffer_empty_cpu(buffer, cpu)) |
1775 | continue; | |
dd0e545f | 1776 | |
bc21b478 | 1777 | ent = peek_next_entry(iter, cpu, &ts, &lost_events); |
dd0e545f | 1778 | |
cdd31cd2 IM |
1779 | /* |
1780 | * Pick the entry with the smallest timestamp: | |
1781 | */ | |
3928a8a2 | 1782 | if (ent && (!next || ts < next_ts)) { |
bc0c38d1 SR |
1783 | next = ent; |
1784 | next_cpu = cpu; | |
3928a8a2 | 1785 | next_ts = ts; |
bc21b478 | 1786 | next_lost = lost_events; |
12b5da34 | 1787 | next_size = iter->ent_size; |
bc0c38d1 SR |
1788 | } |
1789 | } | |
1790 | ||
12b5da34 SR |
1791 | iter->ent_size = next_size; |
1792 | ||
bc0c38d1 SR |
1793 | if (ent_cpu) |
1794 | *ent_cpu = next_cpu; | |
1795 | ||
3928a8a2 SR |
1796 | if (ent_ts) |
1797 | *ent_ts = next_ts; | |
1798 | ||
bc21b478 SR |
1799 | if (missing_events) |
1800 | *missing_events = next_lost; | |
1801 | ||
bc0c38d1 SR |
1802 | return next; |
1803 | } | |
1804 | ||
dd0e545f | 1805 | /* Find the next real entry, without updating the iterator itself */ |
c4a8e8be FW |
1806 | struct trace_entry *trace_find_next_entry(struct trace_iterator *iter, |
1807 | int *ent_cpu, u64 *ent_ts) | |
bc0c38d1 | 1808 | { |
bc21b478 | 1809 | return __find_next_entry(iter, ent_cpu, NULL, ent_ts); |
dd0e545f SR |
1810 | } |
1811 | ||
1812 | /* Find the next real entry, and increment the iterator to the next entry */ | |
955b61e5 | 1813 | void *trace_find_next_entry_inc(struct trace_iterator *iter) |
dd0e545f | 1814 | { |
bc21b478 SR |
1815 | iter->ent = __find_next_entry(iter, &iter->cpu, |
1816 | &iter->lost_events, &iter->ts); | |
dd0e545f | 1817 | |
3928a8a2 | 1818 | if (iter->ent) |
e2ac8ef5 | 1819 | trace_iterator_increment(iter); |
dd0e545f | 1820 | |
3928a8a2 | 1821 | return iter->ent ? iter : NULL; |
b3806b43 | 1822 | } |
bc0c38d1 | 1823 | |
e309b41d | 1824 | static void trace_consume(struct trace_iterator *iter) |
b3806b43 | 1825 | { |
bc21b478 SR |
1826 | ring_buffer_consume(iter->tr->buffer, iter->cpu, &iter->ts, |
1827 | &iter->lost_events); | |
bc0c38d1 SR |
1828 | } |
1829 | ||
e309b41d | 1830 | static void *s_next(struct seq_file *m, void *v, loff_t *pos) |
bc0c38d1 SR |
1831 | { |
1832 | struct trace_iterator *iter = m->private; | |
bc0c38d1 | 1833 | int i = (int)*pos; |
4e3c3333 | 1834 | void *ent; |
bc0c38d1 | 1835 | |
a63ce5b3 SR |
1836 | WARN_ON_ONCE(iter->leftover); |
1837 | ||
bc0c38d1 SR |
1838 | (*pos)++; |
1839 | ||
1840 | /* can't go backwards */ | |
1841 | if (iter->idx > i) | |
1842 | return NULL; | |
1843 | ||
1844 | if (iter->idx < 0) | |
955b61e5 | 1845 | ent = trace_find_next_entry_inc(iter); |
bc0c38d1 SR |
1846 | else |
1847 | ent = iter; | |
1848 | ||
1849 | while (ent && iter->idx < i) | |
955b61e5 | 1850 | ent = trace_find_next_entry_inc(iter); |
bc0c38d1 SR |
1851 | |
1852 | iter->pos = *pos; | |
1853 | ||
bc0c38d1 SR |
1854 | return ent; |
1855 | } | |
1856 | ||
955b61e5 | 1857 | void tracing_iter_reset(struct trace_iterator *iter, int cpu) |
2f26ebd5 SR |
1858 | { |
1859 | struct trace_array *tr = iter->tr; | |
1860 | struct ring_buffer_event *event; | |
1861 | struct ring_buffer_iter *buf_iter; | |
1862 | unsigned long entries = 0; | |
1863 | u64 ts; | |
1864 | ||
1865 | tr->data[cpu]->skipped_entries = 0; | |
1866 | ||
6d158a81 SR |
1867 | buf_iter = trace_buffer_iter(iter, cpu); |
1868 | if (!buf_iter) | |
2f26ebd5 SR |
1869 | return; |
1870 | ||
2f26ebd5 SR |
1871 | ring_buffer_iter_reset(buf_iter); |
1872 | ||
1873 | /* | |
1874 | * We could have the case with the max latency tracers | |
1875 | * that a reset never took place on a cpu. This is evident | |
1876 | * by the timestamp being before the start of the buffer. | |
1877 | */ | |
1878 | while ((event = ring_buffer_iter_peek(buf_iter, &ts))) { | |
1879 | if (ts >= iter->tr->time_start) | |
1880 | break; | |
1881 | entries++; | |
1882 | ring_buffer_read(buf_iter, NULL); | |
1883 | } | |
1884 | ||
1885 | tr->data[cpu]->skipped_entries = entries; | |
1886 | } | |
1887 | ||
d7350c3f | 1888 | /* |
d7350c3f FW |
1889 | * The current tracer is copied to avoid a global locking |
1890 | * all around. | |
1891 | */ | |
bc0c38d1 SR |
1892 | static void *s_start(struct seq_file *m, loff_t *pos) |
1893 | { | |
1894 | struct trace_iterator *iter = m->private; | |
d7350c3f | 1895 | static struct tracer *old_tracer; |
b04cc6b1 | 1896 | int cpu_file = iter->cpu_file; |
bc0c38d1 SR |
1897 | void *p = NULL; |
1898 | loff_t l = 0; | |
3928a8a2 | 1899 | int cpu; |
bc0c38d1 | 1900 | |
d7350c3f | 1901 | /* copy the tracer to avoid using a global lock all around */ |
bc0c38d1 | 1902 | mutex_lock(&trace_types_lock); |
d7350c3f FW |
1903 | if (unlikely(old_tracer != current_trace && current_trace)) { |
1904 | old_tracer = current_trace; | |
1905 | *iter->trace = *current_trace; | |
d15f57f2 | 1906 | } |
d7350c3f | 1907 | mutex_unlock(&trace_types_lock); |
bc0c38d1 SR |
1908 | |
1909 | atomic_inc(&trace_record_cmdline_disabled); | |
1910 | ||
bc0c38d1 SR |
1911 | if (*pos != iter->pos) { |
1912 | iter->ent = NULL; | |
1913 | iter->cpu = 0; | |
1914 | iter->idx = -1; | |
1915 | ||
b04cc6b1 FW |
1916 | if (cpu_file == TRACE_PIPE_ALL_CPU) { |
1917 | for_each_tracing_cpu(cpu) | |
2f26ebd5 | 1918 | tracing_iter_reset(iter, cpu); |
b04cc6b1 | 1919 | } else |
2f26ebd5 | 1920 | tracing_iter_reset(iter, cpu_file); |
bc0c38d1 | 1921 | |
ac91d854 | 1922 | iter->leftover = 0; |
bc0c38d1 SR |
1923 | for (p = iter; p && l < *pos; p = s_next(m, p, &l)) |
1924 | ; | |
1925 | ||
1926 | } else { | |
a63ce5b3 SR |
1927 | /* |
1928 | * If we overflowed the seq_file before, then we want | |
1929 | * to just reuse the trace_seq buffer again. | |
1930 | */ | |
1931 | if (iter->leftover) | |
1932 | p = iter; | |
1933 | else { | |
1934 | l = *pos - 1; | |
1935 | p = s_next(m, p, &l); | |
1936 | } | |
bc0c38d1 SR |
1937 | } |
1938 | ||
4f535968 | 1939 | trace_event_read_lock(); |
7e53bd42 | 1940 | trace_access_lock(cpu_file); |
bc0c38d1 SR |
1941 | return p; |
1942 | } | |
1943 | ||
1944 | static void s_stop(struct seq_file *m, void *p) | |
1945 | { | |
7e53bd42 LJ |
1946 | struct trace_iterator *iter = m->private; |
1947 | ||
bc0c38d1 | 1948 | atomic_dec(&trace_record_cmdline_disabled); |
7e53bd42 | 1949 | trace_access_unlock(iter->cpu_file); |
4f535968 | 1950 | trace_event_read_unlock(); |
bc0c38d1 SR |
1951 | } |
1952 | ||
39eaf7ef SR |
1953 | static void |
1954 | get_total_entries(struct trace_array *tr, unsigned long *total, unsigned long *entries) | |
1955 | { | |
1956 | unsigned long count; | |
1957 | int cpu; | |
1958 | ||
1959 | *total = 0; | |
1960 | *entries = 0; | |
1961 | ||
1962 | for_each_tracing_cpu(cpu) { | |
1963 | count = ring_buffer_entries_cpu(tr->buffer, cpu); | |
1964 | /* | |
1965 | * If this buffer has skipped entries, then we hold all | |
1966 | * entries for the trace and we need to ignore the | |
1967 | * ones before the time stamp. | |
1968 | */ | |
1969 | if (tr->data[cpu]->skipped_entries) { | |
1970 | count -= tr->data[cpu]->skipped_entries; | |
1971 | /* total is the same as the entries */ | |
1972 | *total += count; | |
1973 | } else | |
1974 | *total += count + | |
1975 | ring_buffer_overrun_cpu(tr->buffer, cpu); | |
1976 | *entries += count; | |
1977 | } | |
1978 | } | |
1979 | ||
e309b41d | 1980 | static void print_lat_help_header(struct seq_file *m) |
bc0c38d1 | 1981 | { |
a6168353 ME |
1982 | seq_puts(m, "# _------=> CPU# \n"); |
1983 | seq_puts(m, "# / _-----=> irqs-off \n"); | |
1984 | seq_puts(m, "# | / _----=> need-resched \n"); | |
1985 | seq_puts(m, "# || / _---=> hardirq/softirq \n"); | |
1986 | seq_puts(m, "# ||| / _--=> preempt-depth \n"); | |
e6e1e259 SR |
1987 | seq_puts(m, "# |||| / delay \n"); |
1988 | seq_puts(m, "# cmd pid ||||| time | caller \n"); | |
1989 | seq_puts(m, "# \\ / ||||| \\ | / \n"); | |
bc0c38d1 SR |
1990 | } |
1991 | ||
39eaf7ef | 1992 | static void print_event_info(struct trace_array *tr, struct seq_file *m) |
bc0c38d1 | 1993 | { |
39eaf7ef SR |
1994 | unsigned long total; |
1995 | unsigned long entries; | |
1996 | ||
1997 | get_total_entries(tr, &total, &entries); | |
1998 | seq_printf(m, "# entries-in-buffer/entries-written: %lu/%lu #P:%d\n", | |
1999 | entries, total, num_online_cpus()); | |
2000 | seq_puts(m, "#\n"); | |
2001 | } | |
2002 | ||
2003 | static void print_func_help_header(struct trace_array *tr, struct seq_file *m) | |
2004 | { | |
2005 | print_event_info(tr, m); | |
77271ce4 | 2006 | seq_puts(m, "# TASK-PID CPU# TIMESTAMP FUNCTION\n"); |
a6168353 | 2007 | seq_puts(m, "# | | | | |\n"); |
bc0c38d1 SR |
2008 | } |
2009 | ||
39eaf7ef | 2010 | static void print_func_help_header_irq(struct trace_array *tr, struct seq_file *m) |
77271ce4 | 2011 | { |
39eaf7ef | 2012 | print_event_info(tr, m); |
77271ce4 SR |
2013 | seq_puts(m, "# _-----=> irqs-off\n"); |
2014 | seq_puts(m, "# / _----=> need-resched\n"); | |
2015 | seq_puts(m, "# | / _---=> hardirq/softirq\n"); | |
2016 | seq_puts(m, "# || / _--=> preempt-depth\n"); | |
2017 | seq_puts(m, "# ||| / delay\n"); | |
2018 | seq_puts(m, "# TASK-PID CPU# |||| TIMESTAMP FUNCTION\n"); | |
2019 | seq_puts(m, "# | | | |||| | |\n"); | |
2020 | } | |
bc0c38d1 | 2021 | |
62b915f1 | 2022 | void |
bc0c38d1 SR |
2023 | print_trace_header(struct seq_file *m, struct trace_iterator *iter) |
2024 | { | |
2025 | unsigned long sym_flags = (trace_flags & TRACE_ITER_SYM_MASK); | |
2026 | struct trace_array *tr = iter->tr; | |
2027 | struct trace_array_cpu *data = tr->data[tr->cpu]; | |
2028 | struct tracer *type = current_trace; | |
39eaf7ef SR |
2029 | unsigned long entries; |
2030 | unsigned long total; | |
bc0c38d1 SR |
2031 | const char *name = "preemption"; |
2032 | ||
2033 | if (type) | |
2034 | name = type->name; | |
2035 | ||
39eaf7ef | 2036 | get_total_entries(tr, &total, &entries); |
bc0c38d1 | 2037 | |
888b55dc | 2038 | seq_printf(m, "# %s latency trace v1.1.5 on %s\n", |
bc0c38d1 | 2039 | name, UTS_RELEASE); |
888b55dc | 2040 | seq_puts(m, "# -----------------------------------" |
bc0c38d1 | 2041 | "---------------------------------\n"); |
888b55dc | 2042 | seq_printf(m, "# latency: %lu us, #%lu/%lu, CPU#%d |" |
bc0c38d1 | 2043 | " (M:%s VP:%d, KP:%d, SP:%d HP:%d", |
57f50be1 | 2044 | nsecs_to_usecs(data->saved_latency), |
bc0c38d1 | 2045 | entries, |
4c11d7ae | 2046 | total, |
bc0c38d1 SR |
2047 | tr->cpu, |
2048 | #if defined(CONFIG_PREEMPT_NONE) | |
2049 | "server", | |
2050 | #elif defined(CONFIG_PREEMPT_VOLUNTARY) | |
2051 | "desktop", | |
b5c21b45 | 2052 | #elif defined(CONFIG_PREEMPT) |
bc0c38d1 SR |
2053 | "preempt", |
2054 | #else | |
2055 | "unknown", | |
2056 | #endif | |
2057 | /* These are reserved for later use */ | |
2058 | 0, 0, 0, 0); | |
2059 | #ifdef CONFIG_SMP | |
2060 | seq_printf(m, " #P:%d)\n", num_online_cpus()); | |
2061 | #else | |
2062 | seq_puts(m, ")\n"); | |
2063 | #endif | |
888b55dc KM |
2064 | seq_puts(m, "# -----------------\n"); |
2065 | seq_printf(m, "# | task: %.16s-%d " | |
bc0c38d1 | 2066 | "(uid:%d nice:%ld policy:%ld rt_prio:%ld)\n", |
d20b92ab EB |
2067 | data->comm, data->pid, |
2068 | from_kuid_munged(seq_user_ns(m), data->uid), data->nice, | |
bc0c38d1 | 2069 | data->policy, data->rt_priority); |
888b55dc | 2070 | seq_puts(m, "# -----------------\n"); |
bc0c38d1 SR |
2071 | |
2072 | if (data->critical_start) { | |
888b55dc | 2073 | seq_puts(m, "# => started at: "); |
214023c3 SR |
2074 | seq_print_ip_sym(&iter->seq, data->critical_start, sym_flags); |
2075 | trace_print_seq(m, &iter->seq); | |
888b55dc | 2076 | seq_puts(m, "\n# => ended at: "); |
214023c3 SR |
2077 | seq_print_ip_sym(&iter->seq, data->critical_end, sym_flags); |
2078 | trace_print_seq(m, &iter->seq); | |
8248ac05 | 2079 | seq_puts(m, "\n#\n"); |
bc0c38d1 SR |
2080 | } |
2081 | ||
888b55dc | 2082 | seq_puts(m, "#\n"); |
bc0c38d1 SR |
2083 | } |
2084 | ||
a309720c SR |
2085 | static void test_cpu_buff_start(struct trace_iterator *iter) |
2086 | { | |
2087 | struct trace_seq *s = &iter->seq; | |
2088 | ||
12ef7d44 SR |
2089 | if (!(trace_flags & TRACE_ITER_ANNOTATE)) |
2090 | return; | |
2091 | ||
2092 | if (!(iter->iter_flags & TRACE_FILE_ANNOTATE)) | |
2093 | return; | |
2094 | ||
4462344e | 2095 | if (cpumask_test_cpu(iter->cpu, iter->started)) |
a309720c SR |
2096 | return; |
2097 | ||
2f26ebd5 SR |
2098 | if (iter->tr->data[iter->cpu]->skipped_entries) |
2099 | return; | |
2100 | ||
4462344e | 2101 | cpumask_set_cpu(iter->cpu, iter->started); |
b0dfa978 FW |
2102 | |
2103 | /* Don't print started cpu buffer for the first entry of the trace */ | |
2104 | if (iter->idx > 1) | |
2105 | trace_seq_printf(s, "##### CPU %u buffer started ####\n", | |
2106 | iter->cpu); | |
a309720c SR |
2107 | } |
2108 | ||
2c4f035f | 2109 | static enum print_line_t print_trace_fmt(struct trace_iterator *iter) |
bc0c38d1 | 2110 | { |
214023c3 | 2111 | struct trace_seq *s = &iter->seq; |
bc0c38d1 | 2112 | unsigned long sym_flags = (trace_flags & TRACE_ITER_SYM_MASK); |
4e3c3333 | 2113 | struct trace_entry *entry; |
f633cef0 | 2114 | struct trace_event *event; |
bc0c38d1 | 2115 | |
4e3c3333 | 2116 | entry = iter->ent; |
dd0e545f | 2117 | |
a309720c SR |
2118 | test_cpu_buff_start(iter); |
2119 | ||
c4a8e8be | 2120 | event = ftrace_find_event(entry->type); |
bc0c38d1 | 2121 | |
c4a8e8be | 2122 | if (trace_flags & TRACE_ITER_CONTEXT_INFO) { |
27d48be8 SR |
2123 | if (iter->iter_flags & TRACE_FILE_LAT_FMT) { |
2124 | if (!trace_print_lat_context(iter)) | |
2125 | goto partial; | |
2126 | } else { | |
2127 | if (!trace_print_context(iter)) | |
2128 | goto partial; | |
2129 | } | |
c4a8e8be | 2130 | } |
bc0c38d1 | 2131 | |
268ccda0 | 2132 | if (event) |
a9a57763 | 2133 | return event->funcs->trace(iter, sym_flags, event); |
d9793bd8 ACM |
2134 | |
2135 | if (!trace_seq_printf(s, "Unknown type %d\n", entry->type)) | |
2136 | goto partial; | |
02b67518 | 2137 | |
2c4f035f | 2138 | return TRACE_TYPE_HANDLED; |
d9793bd8 ACM |
2139 | partial: |
2140 | return TRACE_TYPE_PARTIAL_LINE; | |
bc0c38d1 SR |
2141 | } |
2142 | ||
2c4f035f | 2143 | static enum print_line_t print_raw_fmt(struct trace_iterator *iter) |
f9896bf3 IM |
2144 | { |
2145 | struct trace_seq *s = &iter->seq; | |
2146 | struct trace_entry *entry; | |
f633cef0 | 2147 | struct trace_event *event; |
f9896bf3 IM |
2148 | |
2149 | entry = iter->ent; | |
dd0e545f | 2150 | |
c4a8e8be | 2151 | if (trace_flags & TRACE_ITER_CONTEXT_INFO) { |
d9793bd8 ACM |
2152 | if (!trace_seq_printf(s, "%d %d %llu ", |
2153 | entry->pid, iter->cpu, iter->ts)) | |
2154 | goto partial; | |
c4a8e8be | 2155 | } |
f9896bf3 | 2156 | |
f633cef0 | 2157 | event = ftrace_find_event(entry->type); |
268ccda0 | 2158 | if (event) |
a9a57763 | 2159 | return event->funcs->raw(iter, 0, event); |
d9793bd8 ACM |
2160 | |
2161 | if (!trace_seq_printf(s, "%d ?\n", entry->type)) | |
2162 | goto partial; | |
777e208d | 2163 | |
2c4f035f | 2164 | return TRACE_TYPE_HANDLED; |
d9793bd8 ACM |
2165 | partial: |
2166 | return TRACE_TYPE_PARTIAL_LINE; | |
f9896bf3 IM |
2167 | } |
2168 | ||
2c4f035f | 2169 | static enum print_line_t print_hex_fmt(struct trace_iterator *iter) |
5e3ca0ec IM |
2170 | { |
2171 | struct trace_seq *s = &iter->seq; | |
2172 | unsigned char newline = '\n'; | |
2173 | struct trace_entry *entry; | |
f633cef0 | 2174 | struct trace_event *event; |
5e3ca0ec IM |
2175 | |
2176 | entry = iter->ent; | |
dd0e545f | 2177 | |
c4a8e8be FW |
2178 | if (trace_flags & TRACE_ITER_CONTEXT_INFO) { |
2179 | SEQ_PUT_HEX_FIELD_RET(s, entry->pid); | |
2180 | SEQ_PUT_HEX_FIELD_RET(s, iter->cpu); | |
2181 | SEQ_PUT_HEX_FIELD_RET(s, iter->ts); | |
2182 | } | |
5e3ca0ec | 2183 | |
f633cef0 | 2184 | event = ftrace_find_event(entry->type); |
268ccda0 | 2185 | if (event) { |
a9a57763 | 2186 | enum print_line_t ret = event->funcs->hex(iter, 0, event); |
d9793bd8 ACM |
2187 | if (ret != TRACE_TYPE_HANDLED) |
2188 | return ret; | |
2189 | } | |
7104f300 | 2190 | |
5e3ca0ec IM |
2191 | SEQ_PUT_FIELD_RET(s, newline); |
2192 | ||
2c4f035f | 2193 | return TRACE_TYPE_HANDLED; |
5e3ca0ec IM |
2194 | } |
2195 | ||
2c4f035f | 2196 | static enum print_line_t print_bin_fmt(struct trace_iterator *iter) |
cb0f12aa IM |
2197 | { |
2198 | struct trace_seq *s = &iter->seq; | |
2199 | struct trace_entry *entry; | |
f633cef0 | 2200 | struct trace_event *event; |
cb0f12aa IM |
2201 | |
2202 | entry = iter->ent; | |
dd0e545f | 2203 | |
c4a8e8be FW |
2204 | if (trace_flags & TRACE_ITER_CONTEXT_INFO) { |
2205 | SEQ_PUT_FIELD_RET(s, entry->pid); | |
1830b52d | 2206 | SEQ_PUT_FIELD_RET(s, iter->cpu); |
c4a8e8be FW |
2207 | SEQ_PUT_FIELD_RET(s, iter->ts); |
2208 | } | |
cb0f12aa | 2209 | |
f633cef0 | 2210 | event = ftrace_find_event(entry->type); |
a9a57763 SR |
2211 | return event ? event->funcs->binary(iter, 0, event) : |
2212 | TRACE_TYPE_HANDLED; | |
cb0f12aa IM |
2213 | } |
2214 | ||
62b915f1 | 2215 | int trace_empty(struct trace_iterator *iter) |
bc0c38d1 | 2216 | { |
6d158a81 | 2217 | struct ring_buffer_iter *buf_iter; |
bc0c38d1 SR |
2218 | int cpu; |
2219 | ||
9aba60fe SR |
2220 | /* If we are looking at one CPU buffer, only check that one */ |
2221 | if (iter->cpu_file != TRACE_PIPE_ALL_CPU) { | |
2222 | cpu = iter->cpu_file; | |
6d158a81 SR |
2223 | buf_iter = trace_buffer_iter(iter, cpu); |
2224 | if (buf_iter) { | |
2225 | if (!ring_buffer_iter_empty(buf_iter)) | |
9aba60fe SR |
2226 | return 0; |
2227 | } else { | |
2228 | if (!ring_buffer_empty_cpu(iter->tr->buffer, cpu)) | |
2229 | return 0; | |
2230 | } | |
2231 | return 1; | |
2232 | } | |
2233 | ||
ab46428c | 2234 | for_each_tracing_cpu(cpu) { |
6d158a81 SR |
2235 | buf_iter = trace_buffer_iter(iter, cpu); |
2236 | if (buf_iter) { | |
2237 | if (!ring_buffer_iter_empty(buf_iter)) | |
d769041f SR |
2238 | return 0; |
2239 | } else { | |
2240 | if (!ring_buffer_empty_cpu(iter->tr->buffer, cpu)) | |
2241 | return 0; | |
2242 | } | |
bc0c38d1 | 2243 | } |
d769041f | 2244 | |
797d3712 | 2245 | return 1; |
bc0c38d1 SR |
2246 | } |
2247 | ||
4f535968 | 2248 | /* Called with trace_event_read_lock() held. */ |
955b61e5 | 2249 | enum print_line_t print_trace_line(struct trace_iterator *iter) |
f9896bf3 | 2250 | { |
2c4f035f FW |
2251 | enum print_line_t ret; |
2252 | ||
ee5e51f5 JO |
2253 | if (iter->lost_events && |
2254 | !trace_seq_printf(&iter->seq, "CPU:%d [LOST %lu EVENTS]\n", | |
2255 | iter->cpu, iter->lost_events)) | |
2256 | return TRACE_TYPE_PARTIAL_LINE; | |
bc21b478 | 2257 | |
2c4f035f FW |
2258 | if (iter->trace && iter->trace->print_line) { |
2259 | ret = iter->trace->print_line(iter); | |
2260 | if (ret != TRACE_TYPE_UNHANDLED) | |
2261 | return ret; | |
2262 | } | |
72829bc3 | 2263 | |
48ead020 FW |
2264 | if (iter->ent->type == TRACE_BPRINT && |
2265 | trace_flags & TRACE_ITER_PRINTK && | |
2266 | trace_flags & TRACE_ITER_PRINTK_MSGONLY) | |
5ef841f6 | 2267 | return trace_print_bprintk_msg_only(iter); |
48ead020 | 2268 | |
66896a85 FW |
2269 | if (iter->ent->type == TRACE_PRINT && |
2270 | trace_flags & TRACE_ITER_PRINTK && | |
2271 | trace_flags & TRACE_ITER_PRINTK_MSGONLY) | |
5ef841f6 | 2272 | return trace_print_printk_msg_only(iter); |
66896a85 | 2273 | |
cb0f12aa IM |
2274 | if (trace_flags & TRACE_ITER_BIN) |
2275 | return print_bin_fmt(iter); | |
2276 | ||
5e3ca0ec IM |
2277 | if (trace_flags & TRACE_ITER_HEX) |
2278 | return print_hex_fmt(iter); | |
2279 | ||
f9896bf3 IM |
2280 | if (trace_flags & TRACE_ITER_RAW) |
2281 | return print_raw_fmt(iter); | |
2282 | ||
f9896bf3 IM |
2283 | return print_trace_fmt(iter); |
2284 | } | |
2285 | ||
7e9a49ef JO |
2286 | void trace_latency_header(struct seq_file *m) |
2287 | { | |
2288 | struct trace_iterator *iter = m->private; | |
2289 | ||
2290 | /* print nothing if the buffers are empty */ | |
2291 | if (trace_empty(iter)) | |
2292 | return; | |
2293 | ||
2294 | if (iter->iter_flags & TRACE_FILE_LAT_FMT) | |
2295 | print_trace_header(m, iter); | |
2296 | ||
2297 | if (!(trace_flags & TRACE_ITER_VERBOSE)) | |
2298 | print_lat_help_header(m); | |
2299 | } | |
2300 | ||
62b915f1 JO |
2301 | void trace_default_header(struct seq_file *m) |
2302 | { | |
2303 | struct trace_iterator *iter = m->private; | |
2304 | ||
f56e7f8e JO |
2305 | if (!(trace_flags & TRACE_ITER_CONTEXT_INFO)) |
2306 | return; | |
2307 | ||
62b915f1 JO |
2308 | if (iter->iter_flags & TRACE_FILE_LAT_FMT) { |
2309 | /* print nothing if the buffers are empty */ | |
2310 | if (trace_empty(iter)) | |
2311 | return; | |
2312 | print_trace_header(m, iter); | |
2313 | if (!(trace_flags & TRACE_ITER_VERBOSE)) | |
2314 | print_lat_help_header(m); | |
2315 | } else { | |
77271ce4 SR |
2316 | if (!(trace_flags & TRACE_ITER_VERBOSE)) { |
2317 | if (trace_flags & TRACE_ITER_IRQ_INFO) | |
39eaf7ef | 2318 | print_func_help_header_irq(iter->tr, m); |
77271ce4 | 2319 | else |
39eaf7ef | 2320 | print_func_help_header(iter->tr, m); |
77271ce4 | 2321 | } |
62b915f1 JO |
2322 | } |
2323 | } | |
2324 | ||
e0a413f6 SR |
2325 | static void test_ftrace_alive(struct seq_file *m) |
2326 | { | |
2327 | if (!ftrace_is_dead()) | |
2328 | return; | |
2329 | seq_printf(m, "# WARNING: FUNCTION TRACING IS CORRUPTED\n"); | |
2330 | seq_printf(m, "# MAY BE MISSING FUNCTION EVENTS\n"); | |
2331 | } | |
2332 | ||
bc0c38d1 SR |
2333 | static int s_show(struct seq_file *m, void *v) |
2334 | { | |
2335 | struct trace_iterator *iter = v; | |
a63ce5b3 | 2336 | int ret; |
bc0c38d1 SR |
2337 | |
2338 | if (iter->ent == NULL) { | |
2339 | if (iter->tr) { | |
2340 | seq_printf(m, "# tracer: %s\n", iter->trace->name); | |
2341 | seq_puts(m, "#\n"); | |
e0a413f6 | 2342 | test_ftrace_alive(m); |
bc0c38d1 | 2343 | } |
8bba1bf5 MM |
2344 | if (iter->trace && iter->trace->print_header) |
2345 | iter->trace->print_header(m); | |
62b915f1 JO |
2346 | else |
2347 | trace_default_header(m); | |
2348 | ||
a63ce5b3 SR |
2349 | } else if (iter->leftover) { |
2350 | /* | |
2351 | * If we filled the seq_file buffer earlier, we | |
2352 | * want to just show it now. | |
2353 | */ | |
2354 | ret = trace_print_seq(m, &iter->seq); | |
2355 | ||
2356 | /* ret should this time be zero, but you never know */ | |
2357 | iter->leftover = ret; | |
2358 | ||
bc0c38d1 | 2359 | } else { |
f9896bf3 | 2360 | print_trace_line(iter); |
a63ce5b3 SR |
2361 | ret = trace_print_seq(m, &iter->seq); |
2362 | /* | |
2363 | * If we overflow the seq_file buffer, then it will | |
2364 | * ask us for this data again at start up. | |
2365 | * Use that instead. | |
2366 | * ret is 0 if seq_file write succeeded. | |
2367 | * -1 otherwise. | |
2368 | */ | |
2369 | iter->leftover = ret; | |
bc0c38d1 SR |
2370 | } |
2371 | ||
2372 | return 0; | |
2373 | } | |
2374 | ||
88e9d34c | 2375 | static const struct seq_operations tracer_seq_ops = { |
4bf39a94 IM |
2376 | .start = s_start, |
2377 | .next = s_next, | |
2378 | .stop = s_stop, | |
2379 | .show = s_show, | |
bc0c38d1 SR |
2380 | }; |
2381 | ||
e309b41d | 2382 | static struct trace_iterator * |
85a2f9b4 | 2383 | __tracing_open(struct inode *inode, struct file *file) |
bc0c38d1 | 2384 | { |
b04cc6b1 | 2385 | long cpu_file = (long) inode->i_private; |
bc0c38d1 | 2386 | struct trace_iterator *iter; |
50e18b94 | 2387 | int cpu; |
bc0c38d1 | 2388 | |
85a2f9b4 SR |
2389 | if (tracing_disabled) |
2390 | return ERR_PTR(-ENODEV); | |
60a11774 | 2391 | |
50e18b94 | 2392 | iter = __seq_open_private(file, &tracer_seq_ops, sizeof(*iter)); |
85a2f9b4 SR |
2393 | if (!iter) |
2394 | return ERR_PTR(-ENOMEM); | |
bc0c38d1 | 2395 | |
6d158a81 SR |
2396 | iter->buffer_iter = kzalloc(sizeof(*iter->buffer_iter) * num_possible_cpus(), |
2397 | GFP_KERNEL); | |
93574fcc DC |
2398 | if (!iter->buffer_iter) |
2399 | goto release; | |
2400 | ||
d7350c3f FW |
2401 | /* |
2402 | * We make a copy of the current tracer to avoid concurrent | |
2403 | * changes on it while we are reading. | |
2404 | */ | |
bc0c38d1 | 2405 | mutex_lock(&trace_types_lock); |
d7350c3f | 2406 | iter->trace = kzalloc(sizeof(*iter->trace), GFP_KERNEL); |
85a2f9b4 | 2407 | if (!iter->trace) |
d7350c3f | 2408 | goto fail; |
85a2f9b4 | 2409 | |
d7350c3f FW |
2410 | if (current_trace) |
2411 | *iter->trace = *current_trace; | |
2412 | ||
79f55997 | 2413 | if (!zalloc_cpumask_var(&iter->started, GFP_KERNEL)) |
b0dfa978 FW |
2414 | goto fail; |
2415 | ||
bc0c38d1 SR |
2416 | if (current_trace && current_trace->print_max) |
2417 | iter->tr = &max_tr; | |
2418 | else | |
b04cc6b1 | 2419 | iter->tr = &global_trace; |
bc0c38d1 | 2420 | iter->pos = -1; |
d7350c3f | 2421 | mutex_init(&iter->mutex); |
b04cc6b1 | 2422 | iter->cpu_file = cpu_file; |
bc0c38d1 | 2423 | |
8bba1bf5 MM |
2424 | /* Notify the tracer early; before we stop tracing. */ |
2425 | if (iter->trace && iter->trace->open) | |
a93751ca | 2426 | iter->trace->open(iter); |
8bba1bf5 | 2427 | |
12ef7d44 SR |
2428 | /* Annotate start of buffers if we had overruns */ |
2429 | if (ring_buffer_overruns(iter->tr->buffer)) | |
2430 | iter->iter_flags |= TRACE_FILE_ANNOTATE; | |
2431 | ||
2f26ebd5 SR |
2432 | /* stop the trace while dumping */ |
2433 | tracing_stop(); | |
2434 | ||
b04cc6b1 FW |
2435 | if (iter->cpu_file == TRACE_PIPE_ALL_CPU) { |
2436 | for_each_tracing_cpu(cpu) { | |
b04cc6b1 | 2437 | iter->buffer_iter[cpu] = |
72c9ddfd DM |
2438 | ring_buffer_read_prepare(iter->tr->buffer, cpu); |
2439 | } | |
2440 | ring_buffer_read_prepare_sync(); | |
2441 | for_each_tracing_cpu(cpu) { | |
2442 | ring_buffer_read_start(iter->buffer_iter[cpu]); | |
2f26ebd5 | 2443 | tracing_iter_reset(iter, cpu); |
b04cc6b1 FW |
2444 | } |
2445 | } else { | |
2446 | cpu = iter->cpu_file; | |
3928a8a2 | 2447 | iter->buffer_iter[cpu] = |
72c9ddfd DM |
2448 | ring_buffer_read_prepare(iter->tr->buffer, cpu); |
2449 | ring_buffer_read_prepare_sync(); | |
2450 | ring_buffer_read_start(iter->buffer_iter[cpu]); | |
2f26ebd5 | 2451 | tracing_iter_reset(iter, cpu); |
3928a8a2 SR |
2452 | } |
2453 | ||
bc0c38d1 SR |
2454 | mutex_unlock(&trace_types_lock); |
2455 | ||
bc0c38d1 | 2456 | return iter; |
3928a8a2 | 2457 | |
d7350c3f | 2458 | fail: |
3928a8a2 | 2459 | mutex_unlock(&trace_types_lock); |
d7350c3f | 2460 | kfree(iter->trace); |
6d158a81 | 2461 | kfree(iter->buffer_iter); |
93574fcc | 2462 | release: |
50e18b94 JO |
2463 | seq_release_private(inode, file); |
2464 | return ERR_PTR(-ENOMEM); | |
bc0c38d1 SR |
2465 | } |
2466 | ||
2467 | int tracing_open_generic(struct inode *inode, struct file *filp) | |
2468 | { | |
60a11774 SR |
2469 | if (tracing_disabled) |
2470 | return -ENODEV; | |
2471 | ||
bc0c38d1 SR |
2472 | filp->private_data = inode->i_private; |
2473 | return 0; | |
2474 | } | |
2475 | ||
4fd27358 | 2476 | static int tracing_release(struct inode *inode, struct file *file) |
bc0c38d1 | 2477 | { |
907f2784 | 2478 | struct seq_file *m = file->private_data; |
4acd4d00 | 2479 | struct trace_iterator *iter; |
3928a8a2 | 2480 | int cpu; |
bc0c38d1 | 2481 | |
4acd4d00 SR |
2482 | if (!(file->f_mode & FMODE_READ)) |
2483 | return 0; | |
2484 | ||
2485 | iter = m->private; | |
2486 | ||
bc0c38d1 | 2487 | mutex_lock(&trace_types_lock); |
3928a8a2 SR |
2488 | for_each_tracing_cpu(cpu) { |
2489 | if (iter->buffer_iter[cpu]) | |
2490 | ring_buffer_read_finish(iter->buffer_iter[cpu]); | |
2491 | } | |
2492 | ||
bc0c38d1 SR |
2493 | if (iter->trace && iter->trace->close) |
2494 | iter->trace->close(iter); | |
2495 | ||
2496 | /* reenable tracing if it was previously enabled */ | |
9036990d | 2497 | tracing_start(); |
bc0c38d1 SR |
2498 | mutex_unlock(&trace_types_lock); |
2499 | ||
d7350c3f | 2500 | mutex_destroy(&iter->mutex); |
b0dfa978 | 2501 | free_cpumask_var(iter->started); |
d7350c3f | 2502 | kfree(iter->trace); |
6d158a81 | 2503 | kfree(iter->buffer_iter); |
50e18b94 | 2504 | seq_release_private(inode, file); |
bc0c38d1 SR |
2505 | return 0; |
2506 | } | |
2507 | ||
2508 | static int tracing_open(struct inode *inode, struct file *file) | |
2509 | { | |
85a2f9b4 SR |
2510 | struct trace_iterator *iter; |
2511 | int ret = 0; | |
bc0c38d1 | 2512 | |
4acd4d00 SR |
2513 | /* If this file was open for write, then erase contents */ |
2514 | if ((file->f_mode & FMODE_WRITE) && | |
8650ae32 | 2515 | (file->f_flags & O_TRUNC)) { |
4acd4d00 | 2516 | long cpu = (long) inode->i_private; |
bc0c38d1 | 2517 | |
4acd4d00 SR |
2518 | if (cpu == TRACE_PIPE_ALL_CPU) |
2519 | tracing_reset_online_cpus(&global_trace); | |
2520 | else | |
2521 | tracing_reset(&global_trace, cpu); | |
2522 | } | |
bc0c38d1 | 2523 | |
4acd4d00 SR |
2524 | if (file->f_mode & FMODE_READ) { |
2525 | iter = __tracing_open(inode, file); | |
2526 | if (IS_ERR(iter)) | |
2527 | ret = PTR_ERR(iter); | |
2528 | else if (trace_flags & TRACE_ITER_LATENCY_FMT) | |
2529 | iter->iter_flags |= TRACE_FILE_LAT_FMT; | |
2530 | } | |
bc0c38d1 SR |
2531 | return ret; |
2532 | } | |
2533 | ||
e309b41d | 2534 | static void * |
bc0c38d1 SR |
2535 | t_next(struct seq_file *m, void *v, loff_t *pos) |
2536 | { | |
f129e965 | 2537 | struct tracer *t = v; |
bc0c38d1 SR |
2538 | |
2539 | (*pos)++; | |
2540 | ||
2541 | if (t) | |
2542 | t = t->next; | |
2543 | ||
bc0c38d1 SR |
2544 | return t; |
2545 | } | |
2546 | ||
2547 | static void *t_start(struct seq_file *m, loff_t *pos) | |
2548 | { | |
f129e965 | 2549 | struct tracer *t; |
bc0c38d1 SR |
2550 | loff_t l = 0; |
2551 | ||
2552 | mutex_lock(&trace_types_lock); | |
f129e965 | 2553 | for (t = trace_types; t && l < *pos; t = t_next(m, t, &l)) |
bc0c38d1 SR |
2554 | ; |
2555 | ||
2556 | return t; | |
2557 | } | |
2558 | ||
2559 | static void t_stop(struct seq_file *m, void *p) | |
2560 | { | |
2561 | mutex_unlock(&trace_types_lock); | |
2562 | } | |
2563 | ||
2564 | static int t_show(struct seq_file *m, void *v) | |
2565 | { | |
2566 | struct tracer *t = v; | |
2567 | ||
2568 | if (!t) | |
2569 | return 0; | |
2570 | ||
2571 | seq_printf(m, "%s", t->name); | |
2572 | if (t->next) | |
2573 | seq_putc(m, ' '); | |
2574 | else | |
2575 | seq_putc(m, '\n'); | |
2576 | ||
2577 | return 0; | |
2578 | } | |
2579 | ||
88e9d34c | 2580 | static const struct seq_operations show_traces_seq_ops = { |
4bf39a94 IM |
2581 | .start = t_start, |
2582 | .next = t_next, | |
2583 | .stop = t_stop, | |
2584 | .show = t_show, | |
bc0c38d1 SR |
2585 | }; |
2586 | ||
2587 | static int show_traces_open(struct inode *inode, struct file *file) | |
2588 | { | |
60a11774 SR |
2589 | if (tracing_disabled) |
2590 | return -ENODEV; | |
2591 | ||
f129e965 | 2592 | return seq_open(file, &show_traces_seq_ops); |
bc0c38d1 SR |
2593 | } |
2594 | ||
4acd4d00 SR |
2595 | static ssize_t |
2596 | tracing_write_stub(struct file *filp, const char __user *ubuf, | |
2597 | size_t count, loff_t *ppos) | |
2598 | { | |
2599 | return count; | |
2600 | } | |
2601 | ||
364829b1 SP |
2602 | static loff_t tracing_seek(struct file *file, loff_t offset, int origin) |
2603 | { | |
2604 | if (file->f_mode & FMODE_READ) | |
2605 | return seq_lseek(file, offset, origin); | |
2606 | else | |
2607 | return 0; | |
2608 | } | |
2609 | ||
5e2336a0 | 2610 | static const struct file_operations tracing_fops = { |
4bf39a94 IM |
2611 | .open = tracing_open, |
2612 | .read = seq_read, | |
4acd4d00 | 2613 | .write = tracing_write_stub, |
364829b1 | 2614 | .llseek = tracing_seek, |
4bf39a94 | 2615 | .release = tracing_release, |
bc0c38d1 SR |
2616 | }; |
2617 | ||
5e2336a0 | 2618 | static const struct file_operations show_traces_fops = { |
c7078de1 IM |
2619 | .open = show_traces_open, |
2620 | .read = seq_read, | |
2621 | .release = seq_release, | |
b444786f | 2622 | .llseek = seq_lseek, |
c7078de1 IM |
2623 | }; |
2624 | ||
36dfe925 IM |
2625 | /* |
2626 | * Only trace on a CPU if the bitmask is set: | |
2627 | */ | |
9e01c1b7 | 2628 | static cpumask_var_t tracing_cpumask; |
36dfe925 IM |
2629 | |
2630 | /* | |
2631 | * The tracer itself will not take this lock, but still we want | |
2632 | * to provide a consistent cpumask to user-space: | |
2633 | */ | |
2634 | static DEFINE_MUTEX(tracing_cpumask_update_lock); | |
2635 | ||
2636 | /* | |
2637 | * Temporary storage for the character representation of the | |
2638 | * CPU bitmask (and one more byte for the newline): | |
2639 | */ | |
2640 | static char mask_str[NR_CPUS + 1]; | |
2641 | ||
c7078de1 IM |
2642 | static ssize_t |
2643 | tracing_cpumask_read(struct file *filp, char __user *ubuf, | |
2644 | size_t count, loff_t *ppos) | |
2645 | { | |
36dfe925 | 2646 | int len; |
c7078de1 IM |
2647 | |
2648 | mutex_lock(&tracing_cpumask_update_lock); | |
36dfe925 | 2649 | |
9e01c1b7 | 2650 | len = cpumask_scnprintf(mask_str, count, tracing_cpumask); |
36dfe925 IM |
2651 | if (count - len < 2) { |
2652 | count = -EINVAL; | |
2653 | goto out_err; | |
2654 | } | |
2655 | len += sprintf(mask_str + len, "\n"); | |
2656 | count = simple_read_from_buffer(ubuf, count, ppos, mask_str, NR_CPUS+1); | |
2657 | ||
2658 | out_err: | |
c7078de1 IM |
2659 | mutex_unlock(&tracing_cpumask_update_lock); |
2660 | ||
2661 | return count; | |
2662 | } | |
2663 | ||
2664 | static ssize_t | |
2665 | tracing_cpumask_write(struct file *filp, const char __user *ubuf, | |
2666 | size_t count, loff_t *ppos) | |
2667 | { | |
36dfe925 | 2668 | int err, cpu; |
9e01c1b7 RR |
2669 | cpumask_var_t tracing_cpumask_new; |
2670 | ||
2671 | if (!alloc_cpumask_var(&tracing_cpumask_new, GFP_KERNEL)) | |
2672 | return -ENOMEM; | |
c7078de1 | 2673 | |
9e01c1b7 | 2674 | err = cpumask_parse_user(ubuf, count, tracing_cpumask_new); |
c7078de1 | 2675 | if (err) |
36dfe925 IM |
2676 | goto err_unlock; |
2677 | ||
215368e8 LZ |
2678 | mutex_lock(&tracing_cpumask_update_lock); |
2679 | ||
a5e25883 | 2680 | local_irq_disable(); |
0199c4e6 | 2681 | arch_spin_lock(&ftrace_max_lock); |
ab46428c | 2682 | for_each_tracing_cpu(cpu) { |
36dfe925 IM |
2683 | /* |
2684 | * Increase/decrease the disabled counter if we are | |
2685 | * about to flip a bit in the cpumask: | |
2686 | */ | |
9e01c1b7 RR |
2687 | if (cpumask_test_cpu(cpu, tracing_cpumask) && |
2688 | !cpumask_test_cpu(cpu, tracing_cpumask_new)) { | |
36dfe925 | 2689 | atomic_inc(&global_trace.data[cpu]->disabled); |
71babb27 | 2690 | ring_buffer_record_disable_cpu(global_trace.buffer, cpu); |
36dfe925 | 2691 | } |
9e01c1b7 RR |
2692 | if (!cpumask_test_cpu(cpu, tracing_cpumask) && |
2693 | cpumask_test_cpu(cpu, tracing_cpumask_new)) { | |
36dfe925 | 2694 | atomic_dec(&global_trace.data[cpu]->disabled); |
71babb27 | 2695 | ring_buffer_record_enable_cpu(global_trace.buffer, cpu); |
36dfe925 IM |
2696 | } |
2697 | } | |
0199c4e6 | 2698 | arch_spin_unlock(&ftrace_max_lock); |
a5e25883 | 2699 | local_irq_enable(); |
36dfe925 | 2700 | |
9e01c1b7 | 2701 | cpumask_copy(tracing_cpumask, tracing_cpumask_new); |
36dfe925 IM |
2702 | |
2703 | mutex_unlock(&tracing_cpumask_update_lock); | |
9e01c1b7 | 2704 | free_cpumask_var(tracing_cpumask_new); |
c7078de1 IM |
2705 | |
2706 | return count; | |
36dfe925 IM |
2707 | |
2708 | err_unlock: | |
215368e8 | 2709 | free_cpumask_var(tracing_cpumask_new); |
36dfe925 IM |
2710 | |
2711 | return err; | |
c7078de1 IM |
2712 | } |
2713 | ||
5e2336a0 | 2714 | static const struct file_operations tracing_cpumask_fops = { |
c7078de1 IM |
2715 | .open = tracing_open_generic, |
2716 | .read = tracing_cpumask_read, | |
2717 | .write = tracing_cpumask_write, | |
b444786f | 2718 | .llseek = generic_file_llseek, |
bc0c38d1 SR |
2719 | }; |
2720 | ||
fdb372ed | 2721 | static int tracing_trace_options_show(struct seq_file *m, void *v) |
bc0c38d1 | 2722 | { |
d8e83d26 SR |
2723 | struct tracer_opt *trace_opts; |
2724 | u32 tracer_flags; | |
d8e83d26 | 2725 | int i; |
adf9f195 | 2726 | |
d8e83d26 SR |
2727 | mutex_lock(&trace_types_lock); |
2728 | tracer_flags = current_trace->flags->val; | |
2729 | trace_opts = current_trace->flags->opts; | |
2730 | ||
bc0c38d1 SR |
2731 | for (i = 0; trace_options[i]; i++) { |
2732 | if (trace_flags & (1 << i)) | |
fdb372ed | 2733 | seq_printf(m, "%s\n", trace_options[i]); |
bc0c38d1 | 2734 | else |
fdb372ed | 2735 | seq_printf(m, "no%s\n", trace_options[i]); |
bc0c38d1 SR |
2736 | } |
2737 | ||
adf9f195 FW |
2738 | for (i = 0; trace_opts[i].name; i++) { |
2739 | if (tracer_flags & trace_opts[i].bit) | |
fdb372ed | 2740 | seq_printf(m, "%s\n", trace_opts[i].name); |
adf9f195 | 2741 | else |
fdb372ed | 2742 | seq_printf(m, "no%s\n", trace_opts[i].name); |
adf9f195 | 2743 | } |
d8e83d26 | 2744 | mutex_unlock(&trace_types_lock); |
adf9f195 | 2745 | |
fdb372ed | 2746 | return 0; |
bc0c38d1 | 2747 | } |
bc0c38d1 | 2748 | |
8d18eaaf LZ |
2749 | static int __set_tracer_option(struct tracer *trace, |
2750 | struct tracer_flags *tracer_flags, | |
2751 | struct tracer_opt *opts, int neg) | |
2752 | { | |
2753 | int ret; | |
bc0c38d1 | 2754 | |
8d18eaaf LZ |
2755 | ret = trace->set_flag(tracer_flags->val, opts->bit, !neg); |
2756 | if (ret) | |
2757 | return ret; | |
2758 | ||
2759 | if (neg) | |
2760 | tracer_flags->val &= ~opts->bit; | |
2761 | else | |
2762 | tracer_flags->val |= opts->bit; | |
2763 | return 0; | |
bc0c38d1 SR |
2764 | } |
2765 | ||
adf9f195 FW |
2766 | /* Try to assign a tracer specific option */ |
2767 | static int set_tracer_option(struct tracer *trace, char *cmp, int neg) | |
2768 | { | |
7770841e | 2769 | struct tracer_flags *tracer_flags = trace->flags; |
adf9f195 | 2770 | struct tracer_opt *opts = NULL; |
8d18eaaf | 2771 | int i; |
adf9f195 | 2772 | |
7770841e Z |
2773 | for (i = 0; tracer_flags->opts[i].name; i++) { |
2774 | opts = &tracer_flags->opts[i]; | |
adf9f195 | 2775 | |
8d18eaaf LZ |
2776 | if (strcmp(cmp, opts->name) == 0) |
2777 | return __set_tracer_option(trace, trace->flags, | |
2778 | opts, neg); | |
adf9f195 | 2779 | } |
adf9f195 | 2780 | |
8d18eaaf | 2781 | return -EINVAL; |
adf9f195 FW |
2782 | } |
2783 | ||
af4617bd SR |
2784 | static void set_tracer_flags(unsigned int mask, int enabled) |
2785 | { | |
2786 | /* do nothing if flag is already set */ | |
2787 | if (!!(trace_flags & mask) == !!enabled) | |
2788 | return; | |
2789 | ||
2790 | if (enabled) | |
2791 | trace_flags |= mask; | |
2792 | else | |
2793 | trace_flags &= ~mask; | |
e870e9a1 LZ |
2794 | |
2795 | if (mask == TRACE_ITER_RECORD_CMD) | |
2796 | trace_event_enable_cmd_record(enabled); | |
750912fa DS |
2797 | |
2798 | if (mask == TRACE_ITER_OVERWRITE) | |
2799 | ring_buffer_change_overwrite(global_trace.buffer, enabled); | |
af4617bd SR |
2800 | } |
2801 | ||
bc0c38d1 | 2802 | static ssize_t |
ee6bce52 | 2803 | tracing_trace_options_write(struct file *filp, const char __user *ubuf, |
bc0c38d1 SR |
2804 | size_t cnt, loff_t *ppos) |
2805 | { | |
2806 | char buf[64]; | |
8d18eaaf | 2807 | char *cmp; |
bc0c38d1 | 2808 | int neg = 0; |
adf9f195 | 2809 | int ret; |
bc0c38d1 SR |
2810 | int i; |
2811 | ||
cffae437 SR |
2812 | if (cnt >= sizeof(buf)) |
2813 | return -EINVAL; | |
bc0c38d1 SR |
2814 | |
2815 | if (copy_from_user(&buf, ubuf, cnt)) | |
2816 | return -EFAULT; | |
2817 | ||
2818 | buf[cnt] = 0; | |
8d18eaaf | 2819 | cmp = strstrip(buf); |
bc0c38d1 | 2820 | |
8d18eaaf | 2821 | if (strncmp(cmp, "no", 2) == 0) { |
bc0c38d1 SR |
2822 | neg = 1; |
2823 | cmp += 2; | |
2824 | } | |
2825 | ||
2826 | for (i = 0; trace_options[i]; i++) { | |
8d18eaaf | 2827 | if (strcmp(cmp, trace_options[i]) == 0) { |
af4617bd | 2828 | set_tracer_flags(1 << i, !neg); |
bc0c38d1 SR |
2829 | break; |
2830 | } | |
2831 | } | |
adf9f195 FW |
2832 | |
2833 | /* If no option could be set, test the specific tracer options */ | |
2834 | if (!trace_options[i]) { | |
d8e83d26 | 2835 | mutex_lock(&trace_types_lock); |
adf9f195 | 2836 | ret = set_tracer_option(current_trace, cmp, neg); |
d8e83d26 | 2837 | mutex_unlock(&trace_types_lock); |
adf9f195 FW |
2838 | if (ret) |
2839 | return ret; | |
2840 | } | |
bc0c38d1 | 2841 | |
cf8517cf | 2842 | *ppos += cnt; |
bc0c38d1 SR |
2843 | |
2844 | return cnt; | |
2845 | } | |
2846 | ||
fdb372ed LZ |
2847 | static int tracing_trace_options_open(struct inode *inode, struct file *file) |
2848 | { | |
2849 | if (tracing_disabled) | |
2850 | return -ENODEV; | |
2851 | return single_open(file, tracing_trace_options_show, NULL); | |
2852 | } | |
2853 | ||
5e2336a0 | 2854 | static const struct file_operations tracing_iter_fops = { |
fdb372ed LZ |
2855 | .open = tracing_trace_options_open, |
2856 | .read = seq_read, | |
2857 | .llseek = seq_lseek, | |
2858 | .release = single_release, | |
ee6bce52 | 2859 | .write = tracing_trace_options_write, |
bc0c38d1 SR |
2860 | }; |
2861 | ||
7bd2f24c IM |
2862 | static const char readme_msg[] = |
2863 | "tracing mini-HOWTO:\n\n" | |
156f5a78 GL |
2864 | "# mount -t debugfs nodev /sys/kernel/debug\n\n" |
2865 | "# cat /sys/kernel/debug/tracing/available_tracers\n" | |
1e42e83f | 2866 | "wakeup wakeup_rt preemptirqsoff preemptoff irqsoff function nop\n\n" |
156f5a78 | 2867 | "# cat /sys/kernel/debug/tracing/current_tracer\n" |
bc2b6871 | 2868 | "nop\n" |
1e42e83f | 2869 | "# echo wakeup > /sys/kernel/debug/tracing/current_tracer\n" |
156f5a78 | 2870 | "# cat /sys/kernel/debug/tracing/current_tracer\n" |
1e42e83f | 2871 | "wakeup\n" |
156f5a78 | 2872 | "# cat /sys/kernel/debug/tracing/trace_options\n" |
7bd2f24c | 2873 | "noprint-parent nosym-offset nosym-addr noverbose\n" |
156f5a78 | 2874 | "# echo print-parent > /sys/kernel/debug/tracing/trace_options\n" |
9b5f8b31 | 2875 | "# echo 1 > /sys/kernel/debug/tracing/tracing_on\n" |
156f5a78 | 2876 | "# cat /sys/kernel/debug/tracing/trace > /tmp/trace.txt\n" |
9b5f8b31 | 2877 | "# echo 0 > /sys/kernel/debug/tracing/tracing_on\n" |
7bd2f24c IM |
2878 | ; |
2879 | ||
2880 | static ssize_t | |
2881 | tracing_readme_read(struct file *filp, char __user *ubuf, | |
2882 | size_t cnt, loff_t *ppos) | |
2883 | { | |
2884 | return simple_read_from_buffer(ubuf, cnt, ppos, | |
2885 | readme_msg, strlen(readme_msg)); | |
2886 | } | |
2887 | ||
5e2336a0 | 2888 | static const struct file_operations tracing_readme_fops = { |
c7078de1 IM |
2889 | .open = tracing_open_generic, |
2890 | .read = tracing_readme_read, | |
b444786f | 2891 | .llseek = generic_file_llseek, |
7bd2f24c IM |
2892 | }; |
2893 | ||
69abe6a5 AP |
2894 | static ssize_t |
2895 | tracing_saved_cmdlines_read(struct file *file, char __user *ubuf, | |
2896 | size_t cnt, loff_t *ppos) | |
2897 | { | |
2898 | char *buf_comm; | |
2899 | char *file_buf; | |
2900 | char *buf; | |
2901 | int len = 0; | |
2902 | int pid; | |
2903 | int i; | |
2904 | ||
2905 | file_buf = kmalloc(SAVED_CMDLINES*(16+TASK_COMM_LEN), GFP_KERNEL); | |
2906 | if (!file_buf) | |
2907 | return -ENOMEM; | |
2908 | ||
2909 | buf_comm = kmalloc(TASK_COMM_LEN, GFP_KERNEL); | |
2910 | if (!buf_comm) { | |
2911 | kfree(file_buf); | |
2912 | return -ENOMEM; | |
2913 | } | |
2914 | ||
2915 | buf = file_buf; | |
2916 | ||
2917 | for (i = 0; i < SAVED_CMDLINES; i++) { | |
2918 | int r; | |
2919 | ||
2920 | pid = map_cmdline_to_pid[i]; | |
2921 | if (pid == -1 || pid == NO_CMDLINE_MAP) | |
2922 | continue; | |
2923 | ||
2924 | trace_find_cmdline(pid, buf_comm); | |
2925 | r = sprintf(buf, "%d %s\n", pid, buf_comm); | |
2926 | buf += r; | |
2927 | len += r; | |
2928 | } | |
2929 | ||
2930 | len = simple_read_from_buffer(ubuf, cnt, ppos, | |
2931 | file_buf, len); | |
2932 | ||
2933 | kfree(file_buf); | |
2934 | kfree(buf_comm); | |
2935 | ||
2936 | return len; | |
2937 | } | |
2938 | ||
2939 | static const struct file_operations tracing_saved_cmdlines_fops = { | |
2940 | .open = tracing_open_generic, | |
2941 | .read = tracing_saved_cmdlines_read, | |
b444786f | 2942 | .llseek = generic_file_llseek, |
69abe6a5 AP |
2943 | }; |
2944 | ||
bc0c38d1 SR |
2945 | static ssize_t |
2946 | tracing_ctrl_read(struct file *filp, char __user *ubuf, | |
2947 | size_t cnt, loff_t *ppos) | |
2948 | { | |
bc0c38d1 SR |
2949 | char buf[64]; |
2950 | int r; | |
2951 | ||
9036990d | 2952 | r = sprintf(buf, "%u\n", tracer_enabled); |
4e3c3333 | 2953 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, r); |
bc0c38d1 SR |
2954 | } |
2955 | ||
2956 | static ssize_t | |
2957 | tracing_ctrl_write(struct file *filp, const char __user *ubuf, | |
2958 | size_t cnt, loff_t *ppos) | |
2959 | { | |
2960 | struct trace_array *tr = filp->private_data; | |
5e39841c | 2961 | unsigned long val; |
c6caeeb1 | 2962 | int ret; |
bc0c38d1 | 2963 | |
22fe9b54 PH |
2964 | ret = kstrtoul_from_user(ubuf, cnt, 10, &val); |
2965 | if (ret) | |
c6caeeb1 | 2966 | return ret; |
bc0c38d1 SR |
2967 | |
2968 | val = !!val; | |
2969 | ||
2970 | mutex_lock(&trace_types_lock); | |
9036990d | 2971 | if (tracer_enabled ^ val) { |
6752ab4a SR |
2972 | |
2973 | /* Only need to warn if this is used to change the state */ | |
2974 | WARN_ONCE(1, "tracing_enabled is deprecated. Use tracing_on"); | |
2975 | ||
9036990d | 2976 | if (val) { |
bc0c38d1 | 2977 | tracer_enabled = 1; |
9036990d SR |
2978 | if (current_trace->start) |
2979 | current_trace->start(tr); | |
2980 | tracing_start(); | |
2981 | } else { | |
bc0c38d1 | 2982 | tracer_enabled = 0; |
9036990d SR |
2983 | tracing_stop(); |
2984 | if (current_trace->stop) | |
2985 | current_trace->stop(tr); | |
2986 | } | |
bc0c38d1 SR |
2987 | } |
2988 | mutex_unlock(&trace_types_lock); | |
2989 | ||
cf8517cf | 2990 | *ppos += cnt; |
bc0c38d1 SR |
2991 | |
2992 | return cnt; | |
2993 | } | |
2994 | ||
2995 | static ssize_t | |
2996 | tracing_set_trace_read(struct file *filp, char __user *ubuf, | |
2997 | size_t cnt, loff_t *ppos) | |
2998 | { | |
ee6c2c1b | 2999 | char buf[MAX_TRACER_SIZE+2]; |
bc0c38d1 SR |
3000 | int r; |
3001 | ||
3002 | mutex_lock(&trace_types_lock); | |
3003 | if (current_trace) | |
3004 | r = sprintf(buf, "%s\n", current_trace->name); | |
3005 | else | |
3006 | r = sprintf(buf, "\n"); | |
3007 | mutex_unlock(&trace_types_lock); | |
3008 | ||
4bf39a94 | 3009 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, r); |
bc0c38d1 SR |
3010 | } |
3011 | ||
b6f11df2 ACM |
3012 | int tracer_init(struct tracer *t, struct trace_array *tr) |
3013 | { | |
3014 | tracing_reset_online_cpus(tr); | |
3015 | return t->init(tr); | |
3016 | } | |
3017 | ||
438ced17 VN |
3018 | static void set_buffer_entries(struct trace_array *tr, unsigned long val) |
3019 | { | |
3020 | int cpu; | |
3021 | for_each_tracing_cpu(cpu) | |
3022 | tr->data[cpu]->entries = val; | |
3023 | } | |
3024 | ||
3025 | static int __tracing_resize_ring_buffer(unsigned long size, int cpu) | |
73c5162a SR |
3026 | { |
3027 | int ret; | |
3028 | ||
3029 | /* | |
3030 | * If kernel or user changes the size of the ring buffer | |
a123c52b SR |
3031 | * we use the size that was given, and we can forget about |
3032 | * expanding it later. | |
73c5162a SR |
3033 | */ |
3034 | ring_buffer_expanded = 1; | |
3035 | ||
b382ede6 SR |
3036 | /* May be called before buffers are initialized */ |
3037 | if (!global_trace.buffer) | |
3038 | return 0; | |
3039 | ||
438ced17 | 3040 | ret = ring_buffer_resize(global_trace.buffer, size, cpu); |
73c5162a SR |
3041 | if (ret < 0) |
3042 | return ret; | |
3043 | ||
ef710e10 KM |
3044 | if (!current_trace->use_max_tr) |
3045 | goto out; | |
3046 | ||
438ced17 | 3047 | ret = ring_buffer_resize(max_tr.buffer, size, cpu); |
73c5162a | 3048 | if (ret < 0) { |
438ced17 VN |
3049 | int r = 0; |
3050 | ||
3051 | if (cpu == RING_BUFFER_ALL_CPUS) { | |
3052 | int i; | |
3053 | for_each_tracing_cpu(i) { | |
3054 | r = ring_buffer_resize(global_trace.buffer, | |
3055 | global_trace.data[i]->entries, | |
3056 | i); | |
3057 | if (r < 0) | |
3058 | break; | |
3059 | } | |
3060 | } else { | |
3061 | r = ring_buffer_resize(global_trace.buffer, | |
3062 | global_trace.data[cpu]->entries, | |
3063 | cpu); | |
3064 | } | |
73c5162a | 3065 | |
73c5162a | 3066 | if (r < 0) { |
a123c52b SR |
3067 | /* |
3068 | * AARGH! We are left with different | |
3069 | * size max buffer!!!! | |
3070 | * The max buffer is our "snapshot" buffer. | |
3071 | * When a tracer needs a snapshot (one of the | |
3072 | * latency tracers), it swaps the max buffer | |
3073 | * with the saved snap shot. We succeeded to | |
3074 | * update the size of the main buffer, but failed to | |
3075 | * update the size of the max buffer. But when we tried | |
3076 | * to reset the main buffer to the original size, we | |
3077 | * failed there too. This is very unlikely to | |
3078 | * happen, but if it does, warn and kill all | |
3079 | * tracing. | |
3080 | */ | |
73c5162a SR |
3081 | WARN_ON(1); |
3082 | tracing_disabled = 1; | |
3083 | } | |
3084 | return ret; | |
3085 | } | |
3086 | ||
438ced17 VN |
3087 | if (cpu == RING_BUFFER_ALL_CPUS) |
3088 | set_buffer_entries(&max_tr, size); | |
3089 | else | |
3090 | max_tr.data[cpu]->entries = size; | |
3091 | ||
ef710e10 | 3092 | out: |
438ced17 VN |
3093 | if (cpu == RING_BUFFER_ALL_CPUS) |
3094 | set_buffer_entries(&global_trace, size); | |
3095 | else | |
3096 | global_trace.data[cpu]->entries = size; | |
73c5162a SR |
3097 | |
3098 | return ret; | |
3099 | } | |
3100 | ||
438ced17 | 3101 | static ssize_t tracing_resize_ring_buffer(unsigned long size, int cpu_id) |
4f271a2a | 3102 | { |
83f40318 | 3103 | int ret = size; |
4f271a2a VN |
3104 | |
3105 | mutex_lock(&trace_types_lock); | |
3106 | ||
438ced17 VN |
3107 | if (cpu_id != RING_BUFFER_ALL_CPUS) { |
3108 | /* make sure, this cpu is enabled in the mask */ | |
3109 | if (!cpumask_test_cpu(cpu_id, tracing_buffer_mask)) { | |
3110 | ret = -EINVAL; | |
3111 | goto out; | |
3112 | } | |
3113 | } | |
4f271a2a | 3114 | |
438ced17 | 3115 | ret = __tracing_resize_ring_buffer(size, cpu_id); |
4f271a2a VN |
3116 | if (ret < 0) |
3117 | ret = -ENOMEM; | |
3118 | ||
438ced17 | 3119 | out: |
4f271a2a VN |
3120 | mutex_unlock(&trace_types_lock); |
3121 | ||
3122 | return ret; | |
3123 | } | |
3124 | ||
ef710e10 | 3125 | |
1852fcce SR |
3126 | /** |
3127 | * tracing_update_buffers - used by tracing facility to expand ring buffers | |
3128 | * | |
3129 | * To save on memory when the tracing is never used on a system with it | |
3130 | * configured in. The ring buffers are set to a minimum size. But once | |
3131 | * a user starts to use the tracing facility, then they need to grow | |
3132 | * to their default size. | |
3133 | * | |
3134 | * This function is to be called when a tracer is about to be used. | |
3135 | */ | |
3136 | int tracing_update_buffers(void) | |
3137 | { | |
3138 | int ret = 0; | |
3139 | ||
1027fcb2 | 3140 | mutex_lock(&trace_types_lock); |
1852fcce | 3141 | if (!ring_buffer_expanded) |
438ced17 VN |
3142 | ret = __tracing_resize_ring_buffer(trace_buf_size, |
3143 | RING_BUFFER_ALL_CPUS); | |
1027fcb2 | 3144 | mutex_unlock(&trace_types_lock); |
1852fcce SR |
3145 | |
3146 | return ret; | |
3147 | } | |
3148 | ||
577b785f SR |
3149 | struct trace_option_dentry; |
3150 | ||
3151 | static struct trace_option_dentry * | |
3152 | create_trace_option_files(struct tracer *tracer); | |
3153 | ||
3154 | static void | |
3155 | destroy_trace_option_files(struct trace_option_dentry *topts); | |
3156 | ||
b2821ae6 | 3157 | static int tracing_set_tracer(const char *buf) |
bc0c38d1 | 3158 | { |
577b785f | 3159 | static struct trace_option_dentry *topts; |
bc0c38d1 SR |
3160 | struct trace_array *tr = &global_trace; |
3161 | struct tracer *t; | |
d9e54076 | 3162 | int ret = 0; |
bc0c38d1 | 3163 | |
1027fcb2 SR |
3164 | mutex_lock(&trace_types_lock); |
3165 | ||
73c5162a | 3166 | if (!ring_buffer_expanded) { |
438ced17 VN |
3167 | ret = __tracing_resize_ring_buffer(trace_buf_size, |
3168 | RING_BUFFER_ALL_CPUS); | |
73c5162a | 3169 | if (ret < 0) |
59f586db | 3170 | goto out; |
73c5162a SR |
3171 | ret = 0; |
3172 | } | |
3173 | ||
bc0c38d1 SR |
3174 | for (t = trace_types; t; t = t->next) { |
3175 | if (strcmp(t->name, buf) == 0) | |
3176 | break; | |
3177 | } | |
c2931e05 FW |
3178 | if (!t) { |
3179 | ret = -EINVAL; | |
3180 | goto out; | |
3181 | } | |
3182 | if (t == current_trace) | |
bc0c38d1 SR |
3183 | goto out; |
3184 | ||
9f029e83 | 3185 | trace_branch_disable(); |
bc0c38d1 SR |
3186 | if (current_trace && current_trace->reset) |
3187 | current_trace->reset(tr); | |
ef710e10 KM |
3188 | if (current_trace && current_trace->use_max_tr) { |
3189 | /* | |
3190 | * We don't free the ring buffer. instead, resize it because | |
3191 | * The max_tr ring buffer has some state (e.g. ring->clock) and | |
3192 | * we want preserve it. | |
3193 | */ | |
438ced17 VN |
3194 | ring_buffer_resize(max_tr.buffer, 1, RING_BUFFER_ALL_CPUS); |
3195 | set_buffer_entries(&max_tr, 1); | |
ef710e10 | 3196 | } |
577b785f SR |
3197 | destroy_trace_option_files(topts); |
3198 | ||
b2ad368b | 3199 | current_trace = &nop_trace; |
577b785f | 3200 | |
b2ad368b AV |
3201 | topts = create_trace_option_files(t); |
3202 | if (t->use_max_tr) { | |
438ced17 VN |
3203 | int cpu; |
3204 | /* we need to make per cpu buffer sizes equivalent */ | |
3205 | for_each_tracing_cpu(cpu) { | |
3206 | ret = ring_buffer_resize(max_tr.buffer, | |
3207 | global_trace.data[cpu]->entries, | |
3208 | cpu); | |
3209 | if (ret < 0) | |
3210 | goto out; | |
3211 | max_tr.data[cpu]->entries = | |
3212 | global_trace.data[cpu]->entries; | |
3213 | } | |
ef710e10 | 3214 | } |
577b785f | 3215 | |
1c80025a | 3216 | if (t->init) { |
b6f11df2 | 3217 | ret = tracer_init(t, tr); |
1c80025a FW |
3218 | if (ret) |
3219 | goto out; | |
3220 | } | |
bc0c38d1 | 3221 | |
b2ad368b | 3222 | current_trace = t; |
9f029e83 | 3223 | trace_branch_enable(tr); |
bc0c38d1 SR |
3224 | out: |
3225 | mutex_unlock(&trace_types_lock); | |
3226 | ||
d9e54076 PZ |
3227 | return ret; |
3228 | } | |
3229 | ||
3230 | static ssize_t | |
3231 | tracing_set_trace_write(struct file *filp, const char __user *ubuf, | |
3232 | size_t cnt, loff_t *ppos) | |
3233 | { | |
ee6c2c1b | 3234 | char buf[MAX_TRACER_SIZE+1]; |
d9e54076 PZ |
3235 | int i; |
3236 | size_t ret; | |
e6e7a65a FW |
3237 | int err; |
3238 | ||
3239 | ret = cnt; | |
d9e54076 | 3240 | |
ee6c2c1b LZ |
3241 | if (cnt > MAX_TRACER_SIZE) |
3242 | cnt = MAX_TRACER_SIZE; | |
d9e54076 PZ |
3243 | |
3244 | if (copy_from_user(&buf, ubuf, cnt)) | |
3245 | return -EFAULT; | |
3246 | ||
3247 | buf[cnt] = 0; | |
3248 | ||
3249 | /* strip ending whitespace. */ | |
3250 | for (i = cnt - 1; i > 0 && isspace(buf[i]); i--) | |
3251 | buf[i] = 0; | |
3252 | ||
e6e7a65a FW |
3253 | err = tracing_set_tracer(buf); |
3254 | if (err) | |
3255 | return err; | |
d9e54076 | 3256 | |
cf8517cf | 3257 | *ppos += ret; |
bc0c38d1 | 3258 | |
c2931e05 | 3259 | return ret; |
bc0c38d1 SR |
3260 | } |
3261 | ||
3262 | static ssize_t | |
3263 | tracing_max_lat_read(struct file *filp, char __user *ubuf, | |
3264 | size_t cnt, loff_t *ppos) | |
3265 | { | |
3266 | unsigned long *ptr = filp->private_data; | |
3267 | char buf[64]; | |
3268 | int r; | |
3269 | ||
cffae437 | 3270 | r = snprintf(buf, sizeof(buf), "%ld\n", |
bc0c38d1 | 3271 | *ptr == (unsigned long)-1 ? -1 : nsecs_to_usecs(*ptr)); |
cffae437 SR |
3272 | if (r > sizeof(buf)) |
3273 | r = sizeof(buf); | |
4bf39a94 | 3274 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, r); |
bc0c38d1 SR |
3275 | } |
3276 | ||
3277 | static ssize_t | |
3278 | tracing_max_lat_write(struct file *filp, const char __user *ubuf, | |
3279 | size_t cnt, loff_t *ppos) | |
3280 | { | |
5e39841c | 3281 | unsigned long *ptr = filp->private_data; |
5e39841c | 3282 | unsigned long val; |
c6caeeb1 | 3283 | int ret; |
bc0c38d1 | 3284 | |
22fe9b54 PH |
3285 | ret = kstrtoul_from_user(ubuf, cnt, 10, &val); |
3286 | if (ret) | |
c6caeeb1 | 3287 | return ret; |
bc0c38d1 SR |
3288 | |
3289 | *ptr = val * 1000; | |
3290 | ||
3291 | return cnt; | |
3292 | } | |
3293 | ||
b3806b43 SR |
3294 | static int tracing_open_pipe(struct inode *inode, struct file *filp) |
3295 | { | |
b04cc6b1 | 3296 | long cpu_file = (long) inode->i_private; |
b3806b43 | 3297 | struct trace_iterator *iter; |
b04cc6b1 | 3298 | int ret = 0; |
b3806b43 SR |
3299 | |
3300 | if (tracing_disabled) | |
3301 | return -ENODEV; | |
3302 | ||
b04cc6b1 FW |
3303 | mutex_lock(&trace_types_lock); |
3304 | ||
b3806b43 SR |
3305 | /* create a buffer to store the information to pass to userspace */ |
3306 | iter = kzalloc(sizeof(*iter), GFP_KERNEL); | |
b04cc6b1 FW |
3307 | if (!iter) { |
3308 | ret = -ENOMEM; | |
3309 | goto out; | |
3310 | } | |
b3806b43 | 3311 | |
d7350c3f FW |
3312 | /* |
3313 | * We make a copy of the current tracer to avoid concurrent | |
3314 | * changes on it while we are reading. | |
3315 | */ | |
3316 | iter->trace = kmalloc(sizeof(*iter->trace), GFP_KERNEL); | |
3317 | if (!iter->trace) { | |
3318 | ret = -ENOMEM; | |
3319 | goto fail; | |
3320 | } | |
3321 | if (current_trace) | |
3322 | *iter->trace = *current_trace; | |
3323 | ||
4462344e | 3324 | if (!alloc_cpumask_var(&iter->started, GFP_KERNEL)) { |
b04cc6b1 | 3325 | ret = -ENOMEM; |
d7350c3f | 3326 | goto fail; |
4462344e RR |
3327 | } |
3328 | ||
a309720c | 3329 | /* trace pipe does not show start of buffer */ |
4462344e | 3330 | cpumask_setall(iter->started); |
a309720c | 3331 | |
112f38a7 SR |
3332 | if (trace_flags & TRACE_ITER_LATENCY_FMT) |
3333 | iter->iter_flags |= TRACE_FILE_LAT_FMT; | |
3334 | ||
b04cc6b1 | 3335 | iter->cpu_file = cpu_file; |
b3806b43 | 3336 | iter->tr = &global_trace; |
d7350c3f | 3337 | mutex_init(&iter->mutex); |
b3806b43 SR |
3338 | filp->private_data = iter; |
3339 | ||
107bad8b SR |
3340 | if (iter->trace->pipe_open) |
3341 | iter->trace->pipe_open(iter); | |
107bad8b | 3342 | |
b444786f | 3343 | nonseekable_open(inode, filp); |
b04cc6b1 FW |
3344 | out: |
3345 | mutex_unlock(&trace_types_lock); | |
3346 | return ret; | |
d7350c3f FW |
3347 | |
3348 | fail: | |
3349 | kfree(iter->trace); | |
3350 | kfree(iter); | |
3351 | mutex_unlock(&trace_types_lock); | |
3352 | return ret; | |
b3806b43 SR |
3353 | } |
3354 | ||
3355 | static int tracing_release_pipe(struct inode *inode, struct file *file) | |
3356 | { | |
3357 | struct trace_iterator *iter = file->private_data; | |
3358 | ||
b04cc6b1 FW |
3359 | mutex_lock(&trace_types_lock); |
3360 | ||
29bf4a5e | 3361 | if (iter->trace->pipe_close) |
c521efd1 SR |
3362 | iter->trace->pipe_close(iter); |
3363 | ||
b04cc6b1 FW |
3364 | mutex_unlock(&trace_types_lock); |
3365 | ||
4462344e | 3366 | free_cpumask_var(iter->started); |
d7350c3f FW |
3367 | mutex_destroy(&iter->mutex); |
3368 | kfree(iter->trace); | |
b3806b43 | 3369 | kfree(iter); |
b3806b43 SR |
3370 | |
3371 | return 0; | |
3372 | } | |
3373 | ||
2a2cc8f7 SSP |
3374 | static unsigned int |
3375 | tracing_poll_pipe(struct file *filp, poll_table *poll_table) | |
3376 | { | |
3377 | struct trace_iterator *iter = filp->private_data; | |
3378 | ||
3379 | if (trace_flags & TRACE_ITER_BLOCK) { | |
3380 | /* | |
3381 | * Always select as readable when in blocking mode | |
3382 | */ | |
3383 | return POLLIN | POLLRDNORM; | |
afc2abc0 | 3384 | } else { |
2a2cc8f7 SSP |
3385 | if (!trace_empty(iter)) |
3386 | return POLLIN | POLLRDNORM; | |
3387 | poll_wait(filp, &trace_wait, poll_table); | |
3388 | if (!trace_empty(iter)) | |
3389 | return POLLIN | POLLRDNORM; | |
3390 | ||
3391 | return 0; | |
3392 | } | |
3393 | } | |
3394 | ||
6eaaa5d5 FW |
3395 | |
3396 | void default_wait_pipe(struct trace_iterator *iter) | |
3397 | { | |
3398 | DEFINE_WAIT(wait); | |
3399 | ||
3400 | prepare_to_wait(&trace_wait, &wait, TASK_INTERRUPTIBLE); | |
3401 | ||
3402 | if (trace_empty(iter)) | |
3403 | schedule(); | |
3404 | ||
3405 | finish_wait(&trace_wait, &wait); | |
3406 | } | |
3407 | ||
3408 | /* | |
3409 | * This is a make-shift waitqueue. | |
3410 | * A tracer might use this callback on some rare cases: | |
3411 | * | |
3412 | * 1) the current tracer might hold the runqueue lock when it wakes up | |
3413 | * a reader, hence a deadlock (sched, function, and function graph tracers) | |
3414 | * 2) the function tracers, trace all functions, we don't want | |
3415 | * the overhead of calling wake_up and friends | |
3416 | * (and tracing them too) | |
3417 | * | |
3418 | * Anyway, this is really very primitive wakeup. | |
3419 | */ | |
3420 | void poll_wait_pipe(struct trace_iterator *iter) | |
3421 | { | |
3422 | set_current_state(TASK_INTERRUPTIBLE); | |
3423 | /* sleep for 100 msecs, and try again. */ | |
3424 | schedule_timeout(HZ / 10); | |
3425 | } | |
3426 | ||
ff98781b EGM |
3427 | /* Must be called with trace_types_lock mutex held. */ |
3428 | static int tracing_wait_pipe(struct file *filp) | |
b3806b43 SR |
3429 | { |
3430 | struct trace_iterator *iter = filp->private_data; | |
b3806b43 | 3431 | |
b3806b43 | 3432 | while (trace_empty(iter)) { |
2dc8f095 | 3433 | |
107bad8b | 3434 | if ((filp->f_flags & O_NONBLOCK)) { |
ff98781b | 3435 | return -EAGAIN; |
107bad8b | 3436 | } |
2dc8f095 | 3437 | |
d7350c3f | 3438 | mutex_unlock(&iter->mutex); |
107bad8b | 3439 | |
6eaaa5d5 | 3440 | iter->trace->wait_pipe(iter); |
b3806b43 | 3441 | |
d7350c3f | 3442 | mutex_lock(&iter->mutex); |
107bad8b | 3443 | |
6eaaa5d5 | 3444 | if (signal_pending(current)) |
ff98781b | 3445 | return -EINTR; |
b3806b43 SR |
3446 | |
3447 | /* | |
3448 | * We block until we read something and tracing is disabled. | |
3449 | * We still block if tracing is disabled, but we have never | |
3450 | * read anything. This allows a user to cat this file, and | |
3451 | * then enable tracing. But after we have read something, | |
3452 | * we give an EOF when tracing is again disabled. | |
3453 | * | |
3454 | * iter->pos will be 0 if we haven't read anything. | |
3455 | */ | |
3456 | if (!tracer_enabled && iter->pos) | |
3457 | break; | |
b3806b43 SR |
3458 | } |
3459 | ||
ff98781b EGM |
3460 | return 1; |
3461 | } | |
3462 | ||
3463 | /* | |
3464 | * Consumer reader. | |
3465 | */ | |
3466 | static ssize_t | |
3467 | tracing_read_pipe(struct file *filp, char __user *ubuf, | |
3468 | size_t cnt, loff_t *ppos) | |
3469 | { | |
3470 | struct trace_iterator *iter = filp->private_data; | |
d7350c3f | 3471 | static struct tracer *old_tracer; |
ff98781b EGM |
3472 | ssize_t sret; |
3473 | ||
3474 | /* return any leftover data */ | |
3475 | sret = trace_seq_to_user(&iter->seq, ubuf, cnt); | |
3476 | if (sret != -EBUSY) | |
3477 | return sret; | |
3478 | ||
f9520750 | 3479 | trace_seq_init(&iter->seq); |
ff98781b | 3480 | |
d7350c3f | 3481 | /* copy the tracer to avoid using a global lock all around */ |
ff98781b | 3482 | mutex_lock(&trace_types_lock); |
d7350c3f FW |
3483 | if (unlikely(old_tracer != current_trace && current_trace)) { |
3484 | old_tracer = current_trace; | |
3485 | *iter->trace = *current_trace; | |
3486 | } | |
3487 | mutex_unlock(&trace_types_lock); | |
3488 | ||
3489 | /* | |
3490 | * Avoid more than one consumer on a single file descriptor | |
3491 | * This is just a matter of traces coherency, the ring buffer itself | |
3492 | * is protected. | |
3493 | */ | |
3494 | mutex_lock(&iter->mutex); | |
ff98781b EGM |
3495 | if (iter->trace->read) { |
3496 | sret = iter->trace->read(iter, filp, ubuf, cnt, ppos); | |
3497 | if (sret) | |
3498 | goto out; | |
3499 | } | |
3500 | ||
3501 | waitagain: | |
3502 | sret = tracing_wait_pipe(filp); | |
3503 | if (sret <= 0) | |
3504 | goto out; | |
3505 | ||
b3806b43 | 3506 | /* stop when tracing is finished */ |
ff98781b EGM |
3507 | if (trace_empty(iter)) { |
3508 | sret = 0; | |
107bad8b | 3509 | goto out; |
ff98781b | 3510 | } |
b3806b43 SR |
3511 | |
3512 | if (cnt >= PAGE_SIZE) | |
3513 | cnt = PAGE_SIZE - 1; | |
3514 | ||
53d0aa77 | 3515 | /* reset all but tr, trace, and overruns */ |
53d0aa77 SR |
3516 | memset(&iter->seq, 0, |
3517 | sizeof(struct trace_iterator) - | |
3518 | offsetof(struct trace_iterator, seq)); | |
4823ed7e | 3519 | iter->pos = -1; |
b3806b43 | 3520 | |
4f535968 | 3521 | trace_event_read_lock(); |
7e53bd42 | 3522 | trace_access_lock(iter->cpu_file); |
955b61e5 | 3523 | while (trace_find_next_entry_inc(iter) != NULL) { |
2c4f035f | 3524 | enum print_line_t ret; |
088b1e42 SR |
3525 | int len = iter->seq.len; |
3526 | ||
f9896bf3 | 3527 | ret = print_trace_line(iter); |
2c4f035f | 3528 | if (ret == TRACE_TYPE_PARTIAL_LINE) { |
088b1e42 SR |
3529 | /* don't print partial lines */ |
3530 | iter->seq.len = len; | |
b3806b43 | 3531 | break; |
088b1e42 | 3532 | } |
b91facc3 FW |
3533 | if (ret != TRACE_TYPE_NO_CONSUME) |
3534 | trace_consume(iter); | |
b3806b43 SR |
3535 | |
3536 | if (iter->seq.len >= cnt) | |
3537 | break; | |
ee5e51f5 JO |
3538 | |
3539 | /* | |
3540 | * Setting the full flag means we reached the trace_seq buffer | |
3541 | * size and we should leave by partial output condition above. | |
3542 | * One of the trace_seq_* functions is not used properly. | |
3543 | */ | |
3544 | WARN_ONCE(iter->seq.full, "full flag set for trace type %d", | |
3545 | iter->ent->type); | |
b3806b43 | 3546 | } |
7e53bd42 | 3547 | trace_access_unlock(iter->cpu_file); |
4f535968 | 3548 | trace_event_read_unlock(); |
b3806b43 | 3549 | |
b3806b43 | 3550 | /* Now copy what we have to the user */ |
6c6c2796 PP |
3551 | sret = trace_seq_to_user(&iter->seq, ubuf, cnt); |
3552 | if (iter->seq.readpos >= iter->seq.len) | |
f9520750 | 3553 | trace_seq_init(&iter->seq); |
9ff4b974 PP |
3554 | |
3555 | /* | |
25985edc | 3556 | * If there was nothing to send to user, in spite of consuming trace |
9ff4b974 PP |
3557 | * entries, go back to wait for more entries. |
3558 | */ | |
6c6c2796 | 3559 | if (sret == -EBUSY) |
9ff4b974 | 3560 | goto waitagain; |
b3806b43 | 3561 | |
107bad8b | 3562 | out: |
d7350c3f | 3563 | mutex_unlock(&iter->mutex); |
107bad8b | 3564 | |
6c6c2796 | 3565 | return sret; |
b3806b43 SR |
3566 | } |
3567 | ||
3c56819b EGM |
3568 | static void tracing_pipe_buf_release(struct pipe_inode_info *pipe, |
3569 | struct pipe_buffer *buf) | |
3570 | { | |
3571 | __free_page(buf->page); | |
3572 | } | |
3573 | ||
3574 | static void tracing_spd_release_pipe(struct splice_pipe_desc *spd, | |
3575 | unsigned int idx) | |
3576 | { | |
3577 | __free_page(spd->pages[idx]); | |
3578 | } | |
3579 | ||
28dfef8f | 3580 | static const struct pipe_buf_operations tracing_pipe_buf_ops = { |
34cd4998 SR |
3581 | .can_merge = 0, |
3582 | .map = generic_pipe_buf_map, | |
3583 | .unmap = generic_pipe_buf_unmap, | |
3584 | .confirm = generic_pipe_buf_confirm, | |
3585 | .release = tracing_pipe_buf_release, | |
3586 | .steal = generic_pipe_buf_steal, | |
3587 | .get = generic_pipe_buf_get, | |
3c56819b EGM |
3588 | }; |
3589 | ||
34cd4998 | 3590 | static size_t |
fa7c7f6e | 3591 | tracing_fill_pipe_page(size_t rem, struct trace_iterator *iter) |
34cd4998 SR |
3592 | { |
3593 | size_t count; | |
3594 | int ret; | |
3595 | ||
3596 | /* Seq buffer is page-sized, exactly what we need. */ | |
3597 | for (;;) { | |
3598 | count = iter->seq.len; | |
3599 | ret = print_trace_line(iter); | |
3600 | count = iter->seq.len - count; | |
3601 | if (rem < count) { | |
3602 | rem = 0; | |
3603 | iter->seq.len -= count; | |
3604 | break; | |
3605 | } | |
3606 | if (ret == TRACE_TYPE_PARTIAL_LINE) { | |
3607 | iter->seq.len -= count; | |
3608 | break; | |
3609 | } | |
3610 | ||
74e7ff8c LJ |
3611 | if (ret != TRACE_TYPE_NO_CONSUME) |
3612 | trace_consume(iter); | |
34cd4998 | 3613 | rem -= count; |
955b61e5 | 3614 | if (!trace_find_next_entry_inc(iter)) { |
34cd4998 SR |
3615 | rem = 0; |
3616 | iter->ent = NULL; | |
3617 | break; | |
3618 | } | |
3619 | } | |
3620 | ||
3621 | return rem; | |
3622 | } | |
3623 | ||
3c56819b EGM |
3624 | static ssize_t tracing_splice_read_pipe(struct file *filp, |
3625 | loff_t *ppos, | |
3626 | struct pipe_inode_info *pipe, | |
3627 | size_t len, | |
3628 | unsigned int flags) | |
3629 | { | |
35f3d14d JA |
3630 | struct page *pages_def[PIPE_DEF_BUFFERS]; |
3631 | struct partial_page partial_def[PIPE_DEF_BUFFERS]; | |
3c56819b EGM |
3632 | struct trace_iterator *iter = filp->private_data; |
3633 | struct splice_pipe_desc spd = { | |
35f3d14d JA |
3634 | .pages = pages_def, |
3635 | .partial = partial_def, | |
34cd4998 | 3636 | .nr_pages = 0, /* This gets updated below. */ |
047fe360 | 3637 | .nr_pages_max = PIPE_DEF_BUFFERS, |
34cd4998 SR |
3638 | .flags = flags, |
3639 | .ops = &tracing_pipe_buf_ops, | |
3640 | .spd_release = tracing_spd_release_pipe, | |
3c56819b | 3641 | }; |
d7350c3f | 3642 | static struct tracer *old_tracer; |
3c56819b | 3643 | ssize_t ret; |
34cd4998 | 3644 | size_t rem; |
3c56819b EGM |
3645 | unsigned int i; |
3646 | ||
35f3d14d JA |
3647 | if (splice_grow_spd(pipe, &spd)) |
3648 | return -ENOMEM; | |
3649 | ||
d7350c3f | 3650 | /* copy the tracer to avoid using a global lock all around */ |
3c56819b | 3651 | mutex_lock(&trace_types_lock); |
d7350c3f FW |
3652 | if (unlikely(old_tracer != current_trace && current_trace)) { |
3653 | old_tracer = current_trace; | |
3654 | *iter->trace = *current_trace; | |
3655 | } | |
3656 | mutex_unlock(&trace_types_lock); | |
3657 | ||
3658 | mutex_lock(&iter->mutex); | |
3c56819b EGM |
3659 | |
3660 | if (iter->trace->splice_read) { | |
3661 | ret = iter->trace->splice_read(iter, filp, | |
3662 | ppos, pipe, len, flags); | |
3663 | if (ret) | |
34cd4998 | 3664 | goto out_err; |
3c56819b EGM |
3665 | } |
3666 | ||
3667 | ret = tracing_wait_pipe(filp); | |
3668 | if (ret <= 0) | |
34cd4998 | 3669 | goto out_err; |
3c56819b | 3670 | |
955b61e5 | 3671 | if (!iter->ent && !trace_find_next_entry_inc(iter)) { |
3c56819b | 3672 | ret = -EFAULT; |
34cd4998 | 3673 | goto out_err; |
3c56819b EGM |
3674 | } |
3675 | ||
4f535968 | 3676 | trace_event_read_lock(); |
7e53bd42 | 3677 | trace_access_lock(iter->cpu_file); |
4f535968 | 3678 | |
3c56819b | 3679 | /* Fill as many pages as possible. */ |
35f3d14d JA |
3680 | for (i = 0, rem = len; i < pipe->buffers && rem; i++) { |
3681 | spd.pages[i] = alloc_page(GFP_KERNEL); | |
3682 | if (!spd.pages[i]) | |
34cd4998 | 3683 | break; |
3c56819b | 3684 | |
fa7c7f6e | 3685 | rem = tracing_fill_pipe_page(rem, iter); |
3c56819b EGM |
3686 | |
3687 | /* Copy the data into the page, so we can start over. */ | |
3688 | ret = trace_seq_to_buffer(&iter->seq, | |
35f3d14d | 3689 | page_address(spd.pages[i]), |
3c56819b EGM |
3690 | iter->seq.len); |
3691 | if (ret < 0) { | |
35f3d14d | 3692 | __free_page(spd.pages[i]); |
3c56819b EGM |
3693 | break; |
3694 | } | |
35f3d14d JA |
3695 | spd.partial[i].offset = 0; |
3696 | spd.partial[i].len = iter->seq.len; | |
3c56819b | 3697 | |
f9520750 | 3698 | trace_seq_init(&iter->seq); |
3c56819b EGM |
3699 | } |
3700 | ||
7e53bd42 | 3701 | trace_access_unlock(iter->cpu_file); |
4f535968 | 3702 | trace_event_read_unlock(); |
d7350c3f | 3703 | mutex_unlock(&iter->mutex); |
3c56819b EGM |
3704 | |
3705 | spd.nr_pages = i; | |
3706 | ||
35f3d14d JA |
3707 | ret = splice_to_pipe(pipe, &spd); |
3708 | out: | |
047fe360 | 3709 | splice_shrink_spd(&spd); |
35f3d14d | 3710 | return ret; |
3c56819b | 3711 | |
34cd4998 | 3712 | out_err: |
d7350c3f | 3713 | mutex_unlock(&iter->mutex); |
35f3d14d | 3714 | goto out; |
3c56819b EGM |
3715 | } |
3716 | ||
438ced17 VN |
3717 | struct ftrace_entries_info { |
3718 | struct trace_array *tr; | |
3719 | int cpu; | |
3720 | }; | |
3721 | ||
3722 | static int tracing_entries_open(struct inode *inode, struct file *filp) | |
3723 | { | |
3724 | struct ftrace_entries_info *info; | |
3725 | ||
3726 | if (tracing_disabled) | |
3727 | return -ENODEV; | |
3728 | ||
3729 | info = kzalloc(sizeof(*info), GFP_KERNEL); | |
3730 | if (!info) | |
3731 | return -ENOMEM; | |
3732 | ||
3733 | info->tr = &global_trace; | |
3734 | info->cpu = (unsigned long)inode->i_private; | |
3735 | ||
3736 | filp->private_data = info; | |
3737 | ||
3738 | return 0; | |
3739 | } | |
3740 | ||
a98a3c3f SR |
3741 | static ssize_t |
3742 | tracing_entries_read(struct file *filp, char __user *ubuf, | |
3743 | size_t cnt, loff_t *ppos) | |
3744 | { | |
438ced17 VN |
3745 | struct ftrace_entries_info *info = filp->private_data; |
3746 | struct trace_array *tr = info->tr; | |
3747 | char buf[64]; | |
3748 | int r = 0; | |
3749 | ssize_t ret; | |
a98a3c3f | 3750 | |
db526ca3 | 3751 | mutex_lock(&trace_types_lock); |
438ced17 VN |
3752 | |
3753 | if (info->cpu == RING_BUFFER_ALL_CPUS) { | |
3754 | int cpu, buf_size_same; | |
3755 | unsigned long size; | |
3756 | ||
3757 | size = 0; | |
3758 | buf_size_same = 1; | |
3759 | /* check if all cpu sizes are same */ | |
3760 | for_each_tracing_cpu(cpu) { | |
3761 | /* fill in the size from first enabled cpu */ | |
3762 | if (size == 0) | |
3763 | size = tr->data[cpu]->entries; | |
3764 | if (size != tr->data[cpu]->entries) { | |
3765 | buf_size_same = 0; | |
3766 | break; | |
3767 | } | |
3768 | } | |
3769 | ||
3770 | if (buf_size_same) { | |
3771 | if (!ring_buffer_expanded) | |
3772 | r = sprintf(buf, "%lu (expanded: %lu)\n", | |
3773 | size >> 10, | |
3774 | trace_buf_size >> 10); | |
3775 | else | |
3776 | r = sprintf(buf, "%lu\n", size >> 10); | |
3777 | } else | |
3778 | r = sprintf(buf, "X\n"); | |
3779 | } else | |
3780 | r = sprintf(buf, "%lu\n", tr->data[info->cpu]->entries >> 10); | |
3781 | ||
db526ca3 SR |
3782 | mutex_unlock(&trace_types_lock); |
3783 | ||
438ced17 VN |
3784 | ret = simple_read_from_buffer(ubuf, cnt, ppos, buf, r); |
3785 | return ret; | |
a98a3c3f SR |
3786 | } |
3787 | ||
3788 | static ssize_t | |
3789 | tracing_entries_write(struct file *filp, const char __user *ubuf, | |
3790 | size_t cnt, loff_t *ppos) | |
3791 | { | |
438ced17 | 3792 | struct ftrace_entries_info *info = filp->private_data; |
a98a3c3f | 3793 | unsigned long val; |
4f271a2a | 3794 | int ret; |
a98a3c3f | 3795 | |
22fe9b54 PH |
3796 | ret = kstrtoul_from_user(ubuf, cnt, 10, &val); |
3797 | if (ret) | |
c6caeeb1 | 3798 | return ret; |
a98a3c3f SR |
3799 | |
3800 | /* must have at least 1 entry */ | |
3801 | if (!val) | |
3802 | return -EINVAL; | |
3803 | ||
1696b2b0 SR |
3804 | /* value is in KB */ |
3805 | val <<= 10; | |
3806 | ||
438ced17 | 3807 | ret = tracing_resize_ring_buffer(val, info->cpu); |
4f271a2a VN |
3808 | if (ret < 0) |
3809 | return ret; | |
a98a3c3f | 3810 | |
cf8517cf | 3811 | *ppos += cnt; |
a98a3c3f | 3812 | |
4f271a2a VN |
3813 | return cnt; |
3814 | } | |
bf5e6519 | 3815 | |
438ced17 VN |
3816 | static int |
3817 | tracing_entries_release(struct inode *inode, struct file *filp) | |
3818 | { | |
3819 | struct ftrace_entries_info *info = filp->private_data; | |
3820 | ||
3821 | kfree(info); | |
3822 | ||
3823 | return 0; | |
3824 | } | |
3825 | ||
f81ab074 VN |
3826 | static ssize_t |
3827 | tracing_total_entries_read(struct file *filp, char __user *ubuf, | |
3828 | size_t cnt, loff_t *ppos) | |
3829 | { | |
3830 | struct trace_array *tr = filp->private_data; | |
3831 | char buf[64]; | |
3832 | int r, cpu; | |
3833 | unsigned long size = 0, expanded_size = 0; | |
3834 | ||
3835 | mutex_lock(&trace_types_lock); | |
3836 | for_each_tracing_cpu(cpu) { | |
438ced17 | 3837 | size += tr->data[cpu]->entries >> 10; |
f81ab074 VN |
3838 | if (!ring_buffer_expanded) |
3839 | expanded_size += trace_buf_size >> 10; | |
3840 | } | |
3841 | if (ring_buffer_expanded) | |
3842 | r = sprintf(buf, "%lu\n", size); | |
3843 | else | |
3844 | r = sprintf(buf, "%lu (expanded: %lu)\n", size, expanded_size); | |
3845 | mutex_unlock(&trace_types_lock); | |
3846 | ||
3847 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, r); | |
3848 | } | |
3849 | ||
4f271a2a VN |
3850 | static ssize_t |
3851 | tracing_free_buffer_write(struct file *filp, const char __user *ubuf, | |
3852 | size_t cnt, loff_t *ppos) | |
3853 | { | |
3854 | /* | |
3855 | * There is no need to read what the user has written, this function | |
3856 | * is just to make sure that there is no error when "echo" is used | |
3857 | */ | |
3858 | ||
3859 | *ppos += cnt; | |
a98a3c3f SR |
3860 | |
3861 | return cnt; | |
3862 | } | |
3863 | ||
4f271a2a VN |
3864 | static int |
3865 | tracing_free_buffer_release(struct inode *inode, struct file *filp) | |
3866 | { | |
cf30cf67 SR |
3867 | /* disable tracing ? */ |
3868 | if (trace_flags & TRACE_ITER_STOP_ON_FREE) | |
3869 | tracing_off(); | |
4f271a2a | 3870 | /* resize the ring buffer to 0 */ |
438ced17 | 3871 | tracing_resize_ring_buffer(0, RING_BUFFER_ALL_CPUS); |
4f271a2a VN |
3872 | |
3873 | return 0; | |
3874 | } | |
3875 | ||
5bf9a1ee PP |
3876 | static ssize_t |
3877 | tracing_mark_write(struct file *filp, const char __user *ubuf, | |
3878 | size_t cnt, loff_t *fpos) | |
3879 | { | |
d696b58c SR |
3880 | unsigned long addr = (unsigned long)ubuf; |
3881 | struct ring_buffer_event *event; | |
3882 | struct ring_buffer *buffer; | |
3883 | struct print_entry *entry; | |
3884 | unsigned long irq_flags; | |
3885 | struct page *pages[2]; | |
6edb2a8a | 3886 | void *map_page[2]; |
d696b58c SR |
3887 | int nr_pages = 1; |
3888 | ssize_t written; | |
d696b58c SR |
3889 | int offset; |
3890 | int size; | |
3891 | int len; | |
3892 | int ret; | |
6edb2a8a | 3893 | int i; |
5bf9a1ee | 3894 | |
c76f0694 | 3895 | if (tracing_disabled) |
5bf9a1ee PP |
3896 | return -EINVAL; |
3897 | ||
5224c3a3 MSB |
3898 | if (!(trace_flags & TRACE_ITER_MARKERS)) |
3899 | return -EINVAL; | |
3900 | ||
5bf9a1ee PP |
3901 | if (cnt > TRACE_BUF_SIZE) |
3902 | cnt = TRACE_BUF_SIZE; | |
3903 | ||
d696b58c SR |
3904 | /* |
3905 | * Userspace is injecting traces into the kernel trace buffer. | |
3906 | * We want to be as non intrusive as possible. | |
3907 | * To do so, we do not want to allocate any special buffers | |
3908 | * or take any locks, but instead write the userspace data | |
3909 | * straight into the ring buffer. | |
3910 | * | |
3911 | * First we need to pin the userspace buffer into memory, | |
3912 | * which, most likely it is, because it just referenced it. | |
3913 | * But there's no guarantee that it is. By using get_user_pages_fast() | |
3914 | * and kmap_atomic/kunmap_atomic() we can get access to the | |
3915 | * pages directly. We then write the data directly into the | |
3916 | * ring buffer. | |
3917 | */ | |
3918 | BUILD_BUG_ON(TRACE_BUF_SIZE >= PAGE_SIZE); | |
5bf9a1ee | 3919 | |
d696b58c SR |
3920 | /* check if we cross pages */ |
3921 | if ((addr & PAGE_MASK) != ((addr + cnt) & PAGE_MASK)) | |
3922 | nr_pages = 2; | |
3923 | ||
3924 | offset = addr & (PAGE_SIZE - 1); | |
3925 | addr &= PAGE_MASK; | |
3926 | ||
3927 | ret = get_user_pages_fast(addr, nr_pages, 0, pages); | |
3928 | if (ret < nr_pages) { | |
3929 | while (--ret >= 0) | |
3930 | put_page(pages[ret]); | |
3931 | written = -EFAULT; | |
3932 | goto out; | |
5bf9a1ee | 3933 | } |
d696b58c | 3934 | |
6edb2a8a SR |
3935 | for (i = 0; i < nr_pages; i++) |
3936 | map_page[i] = kmap_atomic(pages[i]); | |
d696b58c SR |
3937 | |
3938 | local_save_flags(irq_flags); | |
3939 | size = sizeof(*entry) + cnt + 2; /* possible \n added */ | |
3940 | buffer = global_trace.buffer; | |
3941 | event = trace_buffer_lock_reserve(buffer, TRACE_PRINT, size, | |
3942 | irq_flags, preempt_count()); | |
3943 | if (!event) { | |
3944 | /* Ring buffer disabled, return as if not open for write */ | |
3945 | written = -EBADF; | |
3946 | goto out_unlock; | |
5bf9a1ee | 3947 | } |
d696b58c SR |
3948 | |
3949 | entry = ring_buffer_event_data(event); | |
3950 | entry->ip = _THIS_IP_; | |
3951 | ||
3952 | if (nr_pages == 2) { | |
3953 | len = PAGE_SIZE - offset; | |
6edb2a8a SR |
3954 | memcpy(&entry->buf, map_page[0] + offset, len); |
3955 | memcpy(&entry->buf[len], map_page[1], cnt - len); | |
c13d2f7c | 3956 | } else |
6edb2a8a | 3957 | memcpy(&entry->buf, map_page[0] + offset, cnt); |
5bf9a1ee | 3958 | |
d696b58c SR |
3959 | if (entry->buf[cnt - 1] != '\n') { |
3960 | entry->buf[cnt] = '\n'; | |
3961 | entry->buf[cnt + 1] = '\0'; | |
3962 | } else | |
3963 | entry->buf[cnt] = '\0'; | |
3964 | ||
3965 | ring_buffer_unlock_commit(buffer, event); | |
5bf9a1ee | 3966 | |
d696b58c | 3967 | written = cnt; |
5bf9a1ee | 3968 | |
d696b58c | 3969 | *fpos += written; |
1aa54bca | 3970 | |
d696b58c | 3971 | out_unlock: |
6edb2a8a SR |
3972 | for (i = 0; i < nr_pages; i++){ |
3973 | kunmap_atomic(map_page[i]); | |
3974 | put_page(pages[i]); | |
3975 | } | |
d696b58c | 3976 | out: |
1aa54bca | 3977 | return written; |
5bf9a1ee PP |
3978 | } |
3979 | ||
13f16d20 | 3980 | static int tracing_clock_show(struct seq_file *m, void *v) |
5079f326 | 3981 | { |
5079f326 Z |
3982 | int i; |
3983 | ||
3984 | for (i = 0; i < ARRAY_SIZE(trace_clocks); i++) | |
13f16d20 | 3985 | seq_printf(m, |
5079f326 Z |
3986 | "%s%s%s%s", i ? " " : "", |
3987 | i == trace_clock_id ? "[" : "", trace_clocks[i].name, | |
3988 | i == trace_clock_id ? "]" : ""); | |
13f16d20 | 3989 | seq_putc(m, '\n'); |
5079f326 | 3990 | |
13f16d20 | 3991 | return 0; |
5079f326 Z |
3992 | } |
3993 | ||
3994 | static ssize_t tracing_clock_write(struct file *filp, const char __user *ubuf, | |
3995 | size_t cnt, loff_t *fpos) | |
3996 | { | |
3997 | char buf[64]; | |
3998 | const char *clockstr; | |
3999 | int i; | |
4000 | ||
4001 | if (cnt >= sizeof(buf)) | |
4002 | return -EINVAL; | |
4003 | ||
4004 | if (copy_from_user(&buf, ubuf, cnt)) | |
4005 | return -EFAULT; | |
4006 | ||
4007 | buf[cnt] = 0; | |
4008 | ||
4009 | clockstr = strstrip(buf); | |
4010 | ||
4011 | for (i = 0; i < ARRAY_SIZE(trace_clocks); i++) { | |
4012 | if (strcmp(trace_clocks[i].name, clockstr) == 0) | |
4013 | break; | |
4014 | } | |
4015 | if (i == ARRAY_SIZE(trace_clocks)) | |
4016 | return -EINVAL; | |
4017 | ||
4018 | trace_clock_id = i; | |
4019 | ||
4020 | mutex_lock(&trace_types_lock); | |
4021 | ||
4022 | ring_buffer_set_clock(global_trace.buffer, trace_clocks[i].func); | |
4023 | if (max_tr.buffer) | |
4024 | ring_buffer_set_clock(max_tr.buffer, trace_clocks[i].func); | |
4025 | ||
4026 | mutex_unlock(&trace_types_lock); | |
4027 | ||
4028 | *fpos += cnt; | |
4029 | ||
4030 | return cnt; | |
4031 | } | |
4032 | ||
13f16d20 LZ |
4033 | static int tracing_clock_open(struct inode *inode, struct file *file) |
4034 | { | |
4035 | if (tracing_disabled) | |
4036 | return -ENODEV; | |
4037 | return single_open(file, tracing_clock_show, NULL); | |
4038 | } | |
4039 | ||
5e2336a0 | 4040 | static const struct file_operations tracing_max_lat_fops = { |
4bf39a94 IM |
4041 | .open = tracing_open_generic, |
4042 | .read = tracing_max_lat_read, | |
4043 | .write = tracing_max_lat_write, | |
b444786f | 4044 | .llseek = generic_file_llseek, |
bc0c38d1 SR |
4045 | }; |
4046 | ||
5e2336a0 | 4047 | static const struct file_operations tracing_ctrl_fops = { |
4bf39a94 IM |
4048 | .open = tracing_open_generic, |
4049 | .read = tracing_ctrl_read, | |
4050 | .write = tracing_ctrl_write, | |
b444786f | 4051 | .llseek = generic_file_llseek, |
bc0c38d1 SR |
4052 | }; |
4053 | ||
5e2336a0 | 4054 | static const struct file_operations set_tracer_fops = { |
4bf39a94 IM |
4055 | .open = tracing_open_generic, |
4056 | .read = tracing_set_trace_read, | |
4057 | .write = tracing_set_trace_write, | |
b444786f | 4058 | .llseek = generic_file_llseek, |
bc0c38d1 SR |
4059 | }; |
4060 | ||
5e2336a0 | 4061 | static const struct file_operations tracing_pipe_fops = { |
4bf39a94 | 4062 | .open = tracing_open_pipe, |
2a2cc8f7 | 4063 | .poll = tracing_poll_pipe, |
4bf39a94 | 4064 | .read = tracing_read_pipe, |
3c56819b | 4065 | .splice_read = tracing_splice_read_pipe, |
4bf39a94 | 4066 | .release = tracing_release_pipe, |
b444786f | 4067 | .llseek = no_llseek, |
b3806b43 SR |
4068 | }; |
4069 | ||
5e2336a0 | 4070 | static const struct file_operations tracing_entries_fops = { |
438ced17 | 4071 | .open = tracing_entries_open, |
a98a3c3f SR |
4072 | .read = tracing_entries_read, |
4073 | .write = tracing_entries_write, | |
438ced17 | 4074 | .release = tracing_entries_release, |
b444786f | 4075 | .llseek = generic_file_llseek, |
a98a3c3f SR |
4076 | }; |
4077 | ||
f81ab074 VN |
4078 | static const struct file_operations tracing_total_entries_fops = { |
4079 | .open = tracing_open_generic, | |
4080 | .read = tracing_total_entries_read, | |
4081 | .llseek = generic_file_llseek, | |
4082 | }; | |
4083 | ||
4f271a2a VN |
4084 | static const struct file_operations tracing_free_buffer_fops = { |
4085 | .write = tracing_free_buffer_write, | |
4086 | .release = tracing_free_buffer_release, | |
4087 | }; | |
4088 | ||
5e2336a0 | 4089 | static const struct file_operations tracing_mark_fops = { |
43a15386 | 4090 | .open = tracing_open_generic, |
5bf9a1ee | 4091 | .write = tracing_mark_write, |
b444786f | 4092 | .llseek = generic_file_llseek, |
5bf9a1ee PP |
4093 | }; |
4094 | ||
5079f326 | 4095 | static const struct file_operations trace_clock_fops = { |
13f16d20 LZ |
4096 | .open = tracing_clock_open, |
4097 | .read = seq_read, | |
4098 | .llseek = seq_lseek, | |
4099 | .release = single_release, | |
5079f326 Z |
4100 | .write = tracing_clock_write, |
4101 | }; | |
4102 | ||
2cadf913 SR |
4103 | struct ftrace_buffer_info { |
4104 | struct trace_array *tr; | |
4105 | void *spare; | |
4106 | int cpu; | |
4107 | unsigned int read; | |
4108 | }; | |
4109 | ||
4110 | static int tracing_buffers_open(struct inode *inode, struct file *filp) | |
4111 | { | |
4112 | int cpu = (int)(long)inode->i_private; | |
4113 | struct ftrace_buffer_info *info; | |
4114 | ||
4115 | if (tracing_disabled) | |
4116 | return -ENODEV; | |
4117 | ||
4118 | info = kzalloc(sizeof(*info), GFP_KERNEL); | |
4119 | if (!info) | |
4120 | return -ENOMEM; | |
4121 | ||
4122 | info->tr = &global_trace; | |
4123 | info->cpu = cpu; | |
ddd538f3 | 4124 | info->spare = NULL; |
2cadf913 SR |
4125 | /* Force reading ring buffer for first read */ |
4126 | info->read = (unsigned int)-1; | |
2cadf913 SR |
4127 | |
4128 | filp->private_data = info; | |
4129 | ||
d1e7e02f | 4130 | return nonseekable_open(inode, filp); |
2cadf913 SR |
4131 | } |
4132 | ||
4133 | static ssize_t | |
4134 | tracing_buffers_read(struct file *filp, char __user *ubuf, | |
4135 | size_t count, loff_t *ppos) | |
4136 | { | |
4137 | struct ftrace_buffer_info *info = filp->private_data; | |
2cadf913 SR |
4138 | ssize_t ret; |
4139 | size_t size; | |
4140 | ||
2dc5d12b SR |
4141 | if (!count) |
4142 | return 0; | |
4143 | ||
ddd538f3 | 4144 | if (!info->spare) |
7ea59064 | 4145 | info->spare = ring_buffer_alloc_read_page(info->tr->buffer, info->cpu); |
ddd538f3 LJ |
4146 | if (!info->spare) |
4147 | return -ENOMEM; | |
4148 | ||
2cadf913 SR |
4149 | /* Do we have previous read data to read? */ |
4150 | if (info->read < PAGE_SIZE) | |
4151 | goto read; | |
4152 | ||
7e53bd42 | 4153 | trace_access_lock(info->cpu); |
2cadf913 SR |
4154 | ret = ring_buffer_read_page(info->tr->buffer, |
4155 | &info->spare, | |
4156 | count, | |
4157 | info->cpu, 0); | |
7e53bd42 | 4158 | trace_access_unlock(info->cpu); |
2cadf913 SR |
4159 | if (ret < 0) |
4160 | return 0; | |
4161 | ||
436fc280 SR |
4162 | info->read = 0; |
4163 | ||
2cadf913 SR |
4164 | read: |
4165 | size = PAGE_SIZE - info->read; | |
4166 | if (size > count) | |
4167 | size = count; | |
4168 | ||
4169 | ret = copy_to_user(ubuf, info->spare + info->read, size); | |
2dc5d12b | 4170 | if (ret == size) |
2cadf913 | 4171 | return -EFAULT; |
2dc5d12b SR |
4172 | size -= ret; |
4173 | ||
2cadf913 SR |
4174 | *ppos += size; |
4175 | info->read += size; | |
4176 | ||
4177 | return size; | |
4178 | } | |
4179 | ||
4180 | static int tracing_buffers_release(struct inode *inode, struct file *file) | |
4181 | { | |
4182 | struct ftrace_buffer_info *info = file->private_data; | |
4183 | ||
ddd538f3 LJ |
4184 | if (info->spare) |
4185 | ring_buffer_free_read_page(info->tr->buffer, info->spare); | |
2cadf913 SR |
4186 | kfree(info); |
4187 | ||
4188 | return 0; | |
4189 | } | |
4190 | ||
4191 | struct buffer_ref { | |
4192 | struct ring_buffer *buffer; | |
4193 | void *page; | |
4194 | int ref; | |
4195 | }; | |
4196 | ||
4197 | static void buffer_pipe_buf_release(struct pipe_inode_info *pipe, | |
4198 | struct pipe_buffer *buf) | |
4199 | { | |
4200 | struct buffer_ref *ref = (struct buffer_ref *)buf->private; | |
4201 | ||
4202 | if (--ref->ref) | |
4203 | return; | |
4204 | ||
4205 | ring_buffer_free_read_page(ref->buffer, ref->page); | |
4206 | kfree(ref); | |
4207 | buf->private = 0; | |
4208 | } | |
4209 | ||
2cadf913 SR |
4210 | static void buffer_pipe_buf_get(struct pipe_inode_info *pipe, |
4211 | struct pipe_buffer *buf) | |
4212 | { | |
4213 | struct buffer_ref *ref = (struct buffer_ref *)buf->private; | |
4214 | ||
4215 | ref->ref++; | |
4216 | } | |
4217 | ||
4218 | /* Pipe buffer operations for a buffer. */ | |
28dfef8f | 4219 | static const struct pipe_buf_operations buffer_pipe_buf_ops = { |
2cadf913 SR |
4220 | .can_merge = 0, |
4221 | .map = generic_pipe_buf_map, | |
4222 | .unmap = generic_pipe_buf_unmap, | |
4223 | .confirm = generic_pipe_buf_confirm, | |
4224 | .release = buffer_pipe_buf_release, | |
d55cb6cf | 4225 | .steal = generic_pipe_buf_steal, |
2cadf913 SR |
4226 | .get = buffer_pipe_buf_get, |
4227 | }; | |
4228 | ||
4229 | /* | |
4230 | * Callback from splice_to_pipe(), if we need to release some pages | |
4231 | * at the end of the spd in case we error'ed out in filling the pipe. | |
4232 | */ | |
4233 | static void buffer_spd_release(struct splice_pipe_desc *spd, unsigned int i) | |
4234 | { | |
4235 | struct buffer_ref *ref = | |
4236 | (struct buffer_ref *)spd->partial[i].private; | |
4237 | ||
4238 | if (--ref->ref) | |
4239 | return; | |
4240 | ||
4241 | ring_buffer_free_read_page(ref->buffer, ref->page); | |
4242 | kfree(ref); | |
4243 | spd->partial[i].private = 0; | |
4244 | } | |
4245 | ||
4246 | static ssize_t | |
4247 | tracing_buffers_splice_read(struct file *file, loff_t *ppos, | |
4248 | struct pipe_inode_info *pipe, size_t len, | |
4249 | unsigned int flags) | |
4250 | { | |
4251 | struct ftrace_buffer_info *info = file->private_data; | |
35f3d14d JA |
4252 | struct partial_page partial_def[PIPE_DEF_BUFFERS]; |
4253 | struct page *pages_def[PIPE_DEF_BUFFERS]; | |
2cadf913 | 4254 | struct splice_pipe_desc spd = { |
35f3d14d JA |
4255 | .pages = pages_def, |
4256 | .partial = partial_def, | |
047fe360 | 4257 | .nr_pages_max = PIPE_DEF_BUFFERS, |
2cadf913 SR |
4258 | .flags = flags, |
4259 | .ops = &buffer_pipe_buf_ops, | |
4260 | .spd_release = buffer_spd_release, | |
4261 | }; | |
4262 | struct buffer_ref *ref; | |
93459c6c | 4263 | int entries, size, i; |
2cadf913 SR |
4264 | size_t ret; |
4265 | ||
35f3d14d JA |
4266 | if (splice_grow_spd(pipe, &spd)) |
4267 | return -ENOMEM; | |
4268 | ||
93cfb3c9 LJ |
4269 | if (*ppos & (PAGE_SIZE - 1)) { |
4270 | WARN_ONCE(1, "Ftrace: previous read must page-align\n"); | |
35f3d14d JA |
4271 | ret = -EINVAL; |
4272 | goto out; | |
93cfb3c9 LJ |
4273 | } |
4274 | ||
4275 | if (len & (PAGE_SIZE - 1)) { | |
4276 | WARN_ONCE(1, "Ftrace: splice_read should page-align\n"); | |
35f3d14d JA |
4277 | if (len < PAGE_SIZE) { |
4278 | ret = -EINVAL; | |
4279 | goto out; | |
4280 | } | |
93cfb3c9 LJ |
4281 | len &= PAGE_MASK; |
4282 | } | |
4283 | ||
7e53bd42 | 4284 | trace_access_lock(info->cpu); |
93459c6c SR |
4285 | entries = ring_buffer_entries_cpu(info->tr->buffer, info->cpu); |
4286 | ||
35f3d14d | 4287 | for (i = 0; i < pipe->buffers && len && entries; i++, len -= PAGE_SIZE) { |
2cadf913 SR |
4288 | struct page *page; |
4289 | int r; | |
4290 | ||
4291 | ref = kzalloc(sizeof(*ref), GFP_KERNEL); | |
4292 | if (!ref) | |
4293 | break; | |
4294 | ||
7267fa68 | 4295 | ref->ref = 1; |
2cadf913 | 4296 | ref->buffer = info->tr->buffer; |
7ea59064 | 4297 | ref->page = ring_buffer_alloc_read_page(ref->buffer, info->cpu); |
2cadf913 SR |
4298 | if (!ref->page) { |
4299 | kfree(ref); | |
4300 | break; | |
4301 | } | |
4302 | ||
4303 | r = ring_buffer_read_page(ref->buffer, &ref->page, | |
f2957f1f | 4304 | len, info->cpu, 1); |
2cadf913 | 4305 | if (r < 0) { |
7ea59064 | 4306 | ring_buffer_free_read_page(ref->buffer, ref->page); |
2cadf913 SR |
4307 | kfree(ref); |
4308 | break; | |
4309 | } | |
4310 | ||
4311 | /* | |
4312 | * zero out any left over data, this is going to | |
4313 | * user land. | |
4314 | */ | |
4315 | size = ring_buffer_page_len(ref->page); | |
4316 | if (size < PAGE_SIZE) | |
4317 | memset(ref->page + size, 0, PAGE_SIZE - size); | |
4318 | ||
4319 | page = virt_to_page(ref->page); | |
4320 | ||
4321 | spd.pages[i] = page; | |
4322 | spd.partial[i].len = PAGE_SIZE; | |
4323 | spd.partial[i].offset = 0; | |
4324 | spd.partial[i].private = (unsigned long)ref; | |
4325 | spd.nr_pages++; | |
93cfb3c9 | 4326 | *ppos += PAGE_SIZE; |
93459c6c SR |
4327 | |
4328 | entries = ring_buffer_entries_cpu(info->tr->buffer, info->cpu); | |
2cadf913 SR |
4329 | } |
4330 | ||
7e53bd42 | 4331 | trace_access_unlock(info->cpu); |
2cadf913 SR |
4332 | spd.nr_pages = i; |
4333 | ||
4334 | /* did we read anything? */ | |
4335 | if (!spd.nr_pages) { | |
4336 | if (flags & SPLICE_F_NONBLOCK) | |
4337 | ret = -EAGAIN; | |
4338 | else | |
4339 | ret = 0; | |
4340 | /* TODO: block */ | |
35f3d14d | 4341 | goto out; |
2cadf913 SR |
4342 | } |
4343 | ||
4344 | ret = splice_to_pipe(pipe, &spd); | |
047fe360 | 4345 | splice_shrink_spd(&spd); |
35f3d14d | 4346 | out: |
2cadf913 SR |
4347 | return ret; |
4348 | } | |
4349 | ||
4350 | static const struct file_operations tracing_buffers_fops = { | |
4351 | .open = tracing_buffers_open, | |
4352 | .read = tracing_buffers_read, | |
4353 | .release = tracing_buffers_release, | |
4354 | .splice_read = tracing_buffers_splice_read, | |
4355 | .llseek = no_llseek, | |
4356 | }; | |
4357 | ||
c8d77183 SR |
4358 | static ssize_t |
4359 | tracing_stats_read(struct file *filp, char __user *ubuf, | |
4360 | size_t count, loff_t *ppos) | |
4361 | { | |
4362 | unsigned long cpu = (unsigned long)filp->private_data; | |
4363 | struct trace_array *tr = &global_trace; | |
4364 | struct trace_seq *s; | |
4365 | unsigned long cnt; | |
c64e148a VN |
4366 | unsigned long long t; |
4367 | unsigned long usec_rem; | |
c8d77183 | 4368 | |
e4f2d10f | 4369 | s = kmalloc(sizeof(*s), GFP_KERNEL); |
c8d77183 | 4370 | if (!s) |
a646365c | 4371 | return -ENOMEM; |
c8d77183 SR |
4372 | |
4373 | trace_seq_init(s); | |
4374 | ||
4375 | cnt = ring_buffer_entries_cpu(tr->buffer, cpu); | |
4376 | trace_seq_printf(s, "entries: %ld\n", cnt); | |
4377 | ||
4378 | cnt = ring_buffer_overrun_cpu(tr->buffer, cpu); | |
4379 | trace_seq_printf(s, "overrun: %ld\n", cnt); | |
4380 | ||
4381 | cnt = ring_buffer_commit_overrun_cpu(tr->buffer, cpu); | |
4382 | trace_seq_printf(s, "commit overrun: %ld\n", cnt); | |
4383 | ||
c64e148a VN |
4384 | cnt = ring_buffer_bytes_cpu(tr->buffer, cpu); |
4385 | trace_seq_printf(s, "bytes: %ld\n", cnt); | |
4386 | ||
4387 | t = ns2usecs(ring_buffer_oldest_event_ts(tr->buffer, cpu)); | |
4388 | usec_rem = do_div(t, USEC_PER_SEC); | |
4389 | trace_seq_printf(s, "oldest event ts: %5llu.%06lu\n", t, usec_rem); | |
4390 | ||
4391 | t = ns2usecs(ring_buffer_time_stamp(tr->buffer, cpu)); | |
4392 | usec_rem = do_div(t, USEC_PER_SEC); | |
4393 | trace_seq_printf(s, "now ts: %5llu.%06lu\n", t, usec_rem); | |
4394 | ||
884bfe89 SP |
4395 | cnt = ring_buffer_dropped_events_cpu(tr->buffer, cpu); |
4396 | trace_seq_printf(s, "dropped events: %ld\n", cnt); | |
4397 | ||
c8d77183 SR |
4398 | count = simple_read_from_buffer(ubuf, count, ppos, s->buffer, s->len); |
4399 | ||
4400 | kfree(s); | |
4401 | ||
4402 | return count; | |
4403 | } | |
4404 | ||
4405 | static const struct file_operations tracing_stats_fops = { | |
4406 | .open = tracing_open_generic, | |
4407 | .read = tracing_stats_read, | |
b444786f | 4408 | .llseek = generic_file_llseek, |
c8d77183 SR |
4409 | }; |
4410 | ||
bc0c38d1 SR |
4411 | #ifdef CONFIG_DYNAMIC_FTRACE |
4412 | ||
b807c3d0 SR |
4413 | int __weak ftrace_arch_read_dyn_info(char *buf, int size) |
4414 | { | |
4415 | return 0; | |
4416 | } | |
4417 | ||
bc0c38d1 | 4418 | static ssize_t |
b807c3d0 | 4419 | tracing_read_dyn_info(struct file *filp, char __user *ubuf, |
bc0c38d1 SR |
4420 | size_t cnt, loff_t *ppos) |
4421 | { | |
a26a2a27 SR |
4422 | static char ftrace_dyn_info_buffer[1024]; |
4423 | static DEFINE_MUTEX(dyn_info_mutex); | |
bc0c38d1 | 4424 | unsigned long *p = filp->private_data; |
b807c3d0 | 4425 | char *buf = ftrace_dyn_info_buffer; |
a26a2a27 | 4426 | int size = ARRAY_SIZE(ftrace_dyn_info_buffer); |
bc0c38d1 SR |
4427 | int r; |
4428 | ||
b807c3d0 SR |
4429 | mutex_lock(&dyn_info_mutex); |
4430 | r = sprintf(buf, "%ld ", *p); | |
4bf39a94 | 4431 | |
a26a2a27 | 4432 | r += ftrace_arch_read_dyn_info(buf+r, (size-1)-r); |
b807c3d0 SR |
4433 | buf[r++] = '\n'; |
4434 | ||
4435 | r = simple_read_from_buffer(ubuf, cnt, ppos, buf, r); | |
4436 | ||
4437 | mutex_unlock(&dyn_info_mutex); | |
4438 | ||
4439 | return r; | |
bc0c38d1 SR |
4440 | } |
4441 | ||
5e2336a0 | 4442 | static const struct file_operations tracing_dyn_info_fops = { |
4bf39a94 | 4443 | .open = tracing_open_generic, |
b807c3d0 | 4444 | .read = tracing_read_dyn_info, |
b444786f | 4445 | .llseek = generic_file_llseek, |
bc0c38d1 SR |
4446 | }; |
4447 | #endif | |
4448 | ||
4449 | static struct dentry *d_tracer; | |
4450 | ||
4451 | struct dentry *tracing_init_dentry(void) | |
4452 | { | |
4453 | static int once; | |
4454 | ||
4455 | if (d_tracer) | |
4456 | return d_tracer; | |
4457 | ||
3e1f60b8 FW |
4458 | if (!debugfs_initialized()) |
4459 | return NULL; | |
4460 | ||
bc0c38d1 SR |
4461 | d_tracer = debugfs_create_dir("tracing", NULL); |
4462 | ||
4463 | if (!d_tracer && !once) { | |
4464 | once = 1; | |
4465 | pr_warning("Could not create debugfs directory 'tracing'\n"); | |
4466 | return NULL; | |
4467 | } | |
4468 | ||
4469 | return d_tracer; | |
4470 | } | |
4471 | ||
b04cc6b1 FW |
4472 | static struct dentry *d_percpu; |
4473 | ||
4474 | struct dentry *tracing_dentry_percpu(void) | |
4475 | { | |
4476 | static int once; | |
4477 | struct dentry *d_tracer; | |
4478 | ||
4479 | if (d_percpu) | |
4480 | return d_percpu; | |
4481 | ||
4482 | d_tracer = tracing_init_dentry(); | |
4483 | ||
4484 | if (!d_tracer) | |
4485 | return NULL; | |
4486 | ||
4487 | d_percpu = debugfs_create_dir("per_cpu", d_tracer); | |
4488 | ||
4489 | if (!d_percpu && !once) { | |
4490 | once = 1; | |
4491 | pr_warning("Could not create debugfs directory 'per_cpu'\n"); | |
4492 | return NULL; | |
4493 | } | |
4494 | ||
4495 | return d_percpu; | |
4496 | } | |
4497 | ||
4498 | static void tracing_init_debugfs_percpu(long cpu) | |
4499 | { | |
4500 | struct dentry *d_percpu = tracing_dentry_percpu(); | |
5452af66 | 4501 | struct dentry *d_cpu; |
dd49a38c | 4502 | char cpu_dir[30]; /* 30 characters should be more than enough */ |
b04cc6b1 | 4503 | |
0a3d7ce7 NK |
4504 | if (!d_percpu) |
4505 | return; | |
4506 | ||
dd49a38c | 4507 | snprintf(cpu_dir, 30, "cpu%ld", cpu); |
8656e7a2 FW |
4508 | d_cpu = debugfs_create_dir(cpu_dir, d_percpu); |
4509 | if (!d_cpu) { | |
4510 | pr_warning("Could not create debugfs '%s' entry\n", cpu_dir); | |
4511 | return; | |
4512 | } | |
b04cc6b1 | 4513 | |
8656e7a2 | 4514 | /* per cpu trace_pipe */ |
5452af66 FW |
4515 | trace_create_file("trace_pipe", 0444, d_cpu, |
4516 | (void *) cpu, &tracing_pipe_fops); | |
b04cc6b1 FW |
4517 | |
4518 | /* per cpu trace */ | |
5452af66 FW |
4519 | trace_create_file("trace", 0644, d_cpu, |
4520 | (void *) cpu, &tracing_fops); | |
7f96f93f | 4521 | |
5452af66 FW |
4522 | trace_create_file("trace_pipe_raw", 0444, d_cpu, |
4523 | (void *) cpu, &tracing_buffers_fops); | |
7f96f93f | 4524 | |
c8d77183 SR |
4525 | trace_create_file("stats", 0444, d_cpu, |
4526 | (void *) cpu, &tracing_stats_fops); | |
438ced17 VN |
4527 | |
4528 | trace_create_file("buffer_size_kb", 0444, d_cpu, | |
4529 | (void *) cpu, &tracing_entries_fops); | |
b04cc6b1 FW |
4530 | } |
4531 | ||
60a11774 SR |
4532 | #ifdef CONFIG_FTRACE_SELFTEST |
4533 | /* Let selftest have access to static functions in this file */ | |
4534 | #include "trace_selftest.c" | |
4535 | #endif | |
4536 | ||
577b785f SR |
4537 | struct trace_option_dentry { |
4538 | struct tracer_opt *opt; | |
4539 | struct tracer_flags *flags; | |
4540 | struct dentry *entry; | |
4541 | }; | |
4542 | ||
4543 | static ssize_t | |
4544 | trace_options_read(struct file *filp, char __user *ubuf, size_t cnt, | |
4545 | loff_t *ppos) | |
4546 | { | |
4547 | struct trace_option_dentry *topt = filp->private_data; | |
4548 | char *buf; | |
4549 | ||
4550 | if (topt->flags->val & topt->opt->bit) | |
4551 | buf = "1\n"; | |
4552 | else | |
4553 | buf = "0\n"; | |
4554 | ||
4555 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, 2); | |
4556 | } | |
4557 | ||
4558 | static ssize_t | |
4559 | trace_options_write(struct file *filp, const char __user *ubuf, size_t cnt, | |
4560 | loff_t *ppos) | |
4561 | { | |
4562 | struct trace_option_dentry *topt = filp->private_data; | |
4563 | unsigned long val; | |
577b785f SR |
4564 | int ret; |
4565 | ||
22fe9b54 PH |
4566 | ret = kstrtoul_from_user(ubuf, cnt, 10, &val); |
4567 | if (ret) | |
577b785f SR |
4568 | return ret; |
4569 | ||
8d18eaaf LZ |
4570 | if (val != 0 && val != 1) |
4571 | return -EINVAL; | |
577b785f | 4572 | |
8d18eaaf | 4573 | if (!!(topt->flags->val & topt->opt->bit) != val) { |
577b785f | 4574 | mutex_lock(&trace_types_lock); |
8d18eaaf | 4575 | ret = __set_tracer_option(current_trace, topt->flags, |
c757bea9 | 4576 | topt->opt, !val); |
577b785f SR |
4577 | mutex_unlock(&trace_types_lock); |
4578 | if (ret) | |
4579 | return ret; | |
577b785f SR |
4580 | } |
4581 | ||
4582 | *ppos += cnt; | |
4583 | ||
4584 | return cnt; | |
4585 | } | |
4586 | ||
4587 | ||
4588 | static const struct file_operations trace_options_fops = { | |
4589 | .open = tracing_open_generic, | |
4590 | .read = trace_options_read, | |
4591 | .write = trace_options_write, | |
b444786f | 4592 | .llseek = generic_file_llseek, |
577b785f SR |
4593 | }; |
4594 | ||
a8259075 SR |
4595 | static ssize_t |
4596 | trace_options_core_read(struct file *filp, char __user *ubuf, size_t cnt, | |
4597 | loff_t *ppos) | |
4598 | { | |
4599 | long index = (long)filp->private_data; | |
4600 | char *buf; | |
4601 | ||
4602 | if (trace_flags & (1 << index)) | |
4603 | buf = "1\n"; | |
4604 | else | |
4605 | buf = "0\n"; | |
4606 | ||
4607 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, 2); | |
4608 | } | |
4609 | ||
4610 | static ssize_t | |
4611 | trace_options_core_write(struct file *filp, const char __user *ubuf, size_t cnt, | |
4612 | loff_t *ppos) | |
4613 | { | |
4614 | long index = (long)filp->private_data; | |
a8259075 SR |
4615 | unsigned long val; |
4616 | int ret; | |
4617 | ||
22fe9b54 PH |
4618 | ret = kstrtoul_from_user(ubuf, cnt, 10, &val); |
4619 | if (ret) | |
a8259075 SR |
4620 | return ret; |
4621 | ||
f2d84b65 | 4622 | if (val != 0 && val != 1) |
a8259075 | 4623 | return -EINVAL; |
f2d84b65 | 4624 | set_tracer_flags(1 << index, val); |
a8259075 SR |
4625 | |
4626 | *ppos += cnt; | |
4627 | ||
4628 | return cnt; | |
4629 | } | |
4630 | ||
a8259075 SR |
4631 | static const struct file_operations trace_options_core_fops = { |
4632 | .open = tracing_open_generic, | |
4633 | .read = trace_options_core_read, | |
4634 | .write = trace_options_core_write, | |
b444786f | 4635 | .llseek = generic_file_llseek, |
a8259075 SR |
4636 | }; |
4637 | ||
5452af66 | 4638 | struct dentry *trace_create_file(const char *name, |
f4ae40a6 | 4639 | umode_t mode, |
5452af66 FW |
4640 | struct dentry *parent, |
4641 | void *data, | |
4642 | const struct file_operations *fops) | |
4643 | { | |
4644 | struct dentry *ret; | |
4645 | ||
4646 | ret = debugfs_create_file(name, mode, parent, data, fops); | |
4647 | if (!ret) | |
4648 | pr_warning("Could not create debugfs '%s' entry\n", name); | |
4649 | ||
4650 | return ret; | |
4651 | } | |
4652 | ||
4653 | ||
a8259075 SR |
4654 | static struct dentry *trace_options_init_dentry(void) |
4655 | { | |
4656 | struct dentry *d_tracer; | |
4657 | static struct dentry *t_options; | |
4658 | ||
4659 | if (t_options) | |
4660 | return t_options; | |
4661 | ||
4662 | d_tracer = tracing_init_dentry(); | |
4663 | if (!d_tracer) | |
4664 | return NULL; | |
4665 | ||
4666 | t_options = debugfs_create_dir("options", d_tracer); | |
4667 | if (!t_options) { | |
4668 | pr_warning("Could not create debugfs directory 'options'\n"); | |
4669 | return NULL; | |
4670 | } | |
4671 | ||
4672 | return t_options; | |
4673 | } | |
4674 | ||
577b785f SR |
4675 | static void |
4676 | create_trace_option_file(struct trace_option_dentry *topt, | |
4677 | struct tracer_flags *flags, | |
4678 | struct tracer_opt *opt) | |
4679 | { | |
4680 | struct dentry *t_options; | |
577b785f SR |
4681 | |
4682 | t_options = trace_options_init_dentry(); | |
4683 | if (!t_options) | |
4684 | return; | |
4685 | ||
4686 | topt->flags = flags; | |
4687 | topt->opt = opt; | |
4688 | ||
5452af66 | 4689 | topt->entry = trace_create_file(opt->name, 0644, t_options, topt, |
577b785f SR |
4690 | &trace_options_fops); |
4691 | ||
577b785f SR |
4692 | } |
4693 | ||
4694 | static struct trace_option_dentry * | |
4695 | create_trace_option_files(struct tracer *tracer) | |
4696 | { | |
4697 | struct trace_option_dentry *topts; | |
4698 | struct tracer_flags *flags; | |
4699 | struct tracer_opt *opts; | |
4700 | int cnt; | |
4701 | ||
4702 | if (!tracer) | |
4703 | return NULL; | |
4704 | ||
4705 | flags = tracer->flags; | |
4706 | ||
4707 | if (!flags || !flags->opts) | |
4708 | return NULL; | |
4709 | ||
4710 | opts = flags->opts; | |
4711 | ||
4712 | for (cnt = 0; opts[cnt].name; cnt++) | |
4713 | ; | |
4714 | ||
0cfe8245 | 4715 | topts = kcalloc(cnt + 1, sizeof(*topts), GFP_KERNEL); |
577b785f SR |
4716 | if (!topts) |
4717 | return NULL; | |
4718 | ||
4719 | for (cnt = 0; opts[cnt].name; cnt++) | |
4720 | create_trace_option_file(&topts[cnt], flags, | |
4721 | &opts[cnt]); | |
4722 | ||
4723 | return topts; | |
4724 | } | |
4725 | ||
4726 | static void | |
4727 | destroy_trace_option_files(struct trace_option_dentry *topts) | |
4728 | { | |
4729 | int cnt; | |
4730 | ||
4731 | if (!topts) | |
4732 | return; | |
4733 | ||
4734 | for (cnt = 0; topts[cnt].opt; cnt++) { | |
4735 | if (topts[cnt].entry) | |
4736 | debugfs_remove(topts[cnt].entry); | |
4737 | } | |
4738 | ||
4739 | kfree(topts); | |
4740 | } | |
4741 | ||
a8259075 SR |
4742 | static struct dentry * |
4743 | create_trace_option_core_file(const char *option, long index) | |
4744 | { | |
4745 | struct dentry *t_options; | |
a8259075 SR |
4746 | |
4747 | t_options = trace_options_init_dentry(); | |
4748 | if (!t_options) | |
4749 | return NULL; | |
4750 | ||
5452af66 | 4751 | return trace_create_file(option, 0644, t_options, (void *)index, |
a8259075 | 4752 | &trace_options_core_fops); |
a8259075 SR |
4753 | } |
4754 | ||
4755 | static __init void create_trace_options_dir(void) | |
4756 | { | |
4757 | struct dentry *t_options; | |
a8259075 SR |
4758 | int i; |
4759 | ||
4760 | t_options = trace_options_init_dentry(); | |
4761 | if (!t_options) | |
4762 | return; | |
4763 | ||
5452af66 FW |
4764 | for (i = 0; trace_options[i]; i++) |
4765 | create_trace_option_core_file(trace_options[i], i); | |
a8259075 SR |
4766 | } |
4767 | ||
499e5470 SR |
4768 | static ssize_t |
4769 | rb_simple_read(struct file *filp, char __user *ubuf, | |
4770 | size_t cnt, loff_t *ppos) | |
4771 | { | |
348f0fc2 SR |
4772 | struct trace_array *tr = filp->private_data; |
4773 | struct ring_buffer *buffer = tr->buffer; | |
499e5470 SR |
4774 | char buf[64]; |
4775 | int r; | |
4776 | ||
4777 | if (buffer) | |
4778 | r = ring_buffer_record_is_on(buffer); | |
4779 | else | |
4780 | r = 0; | |
4781 | ||
4782 | r = sprintf(buf, "%d\n", r); | |
4783 | ||
4784 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, r); | |
4785 | } | |
4786 | ||
4787 | static ssize_t | |
4788 | rb_simple_write(struct file *filp, const char __user *ubuf, | |
4789 | size_t cnt, loff_t *ppos) | |
4790 | { | |
348f0fc2 SR |
4791 | struct trace_array *tr = filp->private_data; |
4792 | struct ring_buffer *buffer = tr->buffer; | |
499e5470 SR |
4793 | unsigned long val; |
4794 | int ret; | |
4795 | ||
4796 | ret = kstrtoul_from_user(ubuf, cnt, 10, &val); | |
4797 | if (ret) | |
4798 | return ret; | |
4799 | ||
4800 | if (buffer) { | |
4801 | if (val) | |
4802 | ring_buffer_record_on(buffer); | |
4803 | else | |
4804 | ring_buffer_record_off(buffer); | |
4805 | } | |
4806 | ||
4807 | (*ppos)++; | |
4808 | ||
4809 | return cnt; | |
4810 | } | |
4811 | ||
4812 | static const struct file_operations rb_simple_fops = { | |
4813 | .open = tracing_open_generic, | |
4814 | .read = rb_simple_read, | |
4815 | .write = rb_simple_write, | |
4816 | .llseek = default_llseek, | |
4817 | }; | |
4818 | ||
b5ad384e | 4819 | static __init int tracer_init_debugfs(void) |
bc0c38d1 SR |
4820 | { |
4821 | struct dentry *d_tracer; | |
b04cc6b1 | 4822 | int cpu; |
bc0c38d1 | 4823 | |
7e53bd42 LJ |
4824 | trace_access_lock_init(); |
4825 | ||
bc0c38d1 SR |
4826 | d_tracer = tracing_init_dentry(); |
4827 | ||
5452af66 FW |
4828 | trace_create_file("tracing_enabled", 0644, d_tracer, |
4829 | &global_trace, &tracing_ctrl_fops); | |
bc0c38d1 | 4830 | |
5452af66 FW |
4831 | trace_create_file("trace_options", 0644, d_tracer, |
4832 | NULL, &tracing_iter_fops); | |
bc0c38d1 | 4833 | |
5452af66 FW |
4834 | trace_create_file("tracing_cpumask", 0644, d_tracer, |
4835 | NULL, &tracing_cpumask_fops); | |
4836 | ||
4837 | trace_create_file("trace", 0644, d_tracer, | |
4838 | (void *) TRACE_PIPE_ALL_CPU, &tracing_fops); | |
a8259075 | 4839 | |
5452af66 FW |
4840 | trace_create_file("available_tracers", 0444, d_tracer, |
4841 | &global_trace, &show_traces_fops); | |
4842 | ||
339ae5d3 | 4843 | trace_create_file("current_tracer", 0644, d_tracer, |
5452af66 FW |
4844 | &global_trace, &set_tracer_fops); |
4845 | ||
5d4a9dba | 4846 | #ifdef CONFIG_TRACER_MAX_TRACE |
5452af66 FW |
4847 | trace_create_file("tracing_max_latency", 0644, d_tracer, |
4848 | &tracing_max_latency, &tracing_max_lat_fops); | |
0e950173 | 4849 | #endif |
5452af66 FW |
4850 | |
4851 | trace_create_file("tracing_thresh", 0644, d_tracer, | |
4852 | &tracing_thresh, &tracing_max_lat_fops); | |
a8259075 | 4853 | |
339ae5d3 | 4854 | trace_create_file("README", 0444, d_tracer, |
5452af66 FW |
4855 | NULL, &tracing_readme_fops); |
4856 | ||
4857 | trace_create_file("trace_pipe", 0444, d_tracer, | |
b04cc6b1 | 4858 | (void *) TRACE_PIPE_ALL_CPU, &tracing_pipe_fops); |
5452af66 FW |
4859 | |
4860 | trace_create_file("buffer_size_kb", 0644, d_tracer, | |
438ced17 | 4861 | (void *) RING_BUFFER_ALL_CPUS, &tracing_entries_fops); |
5452af66 | 4862 | |
f81ab074 VN |
4863 | trace_create_file("buffer_total_size_kb", 0444, d_tracer, |
4864 | &global_trace, &tracing_total_entries_fops); | |
4865 | ||
4f271a2a VN |
4866 | trace_create_file("free_buffer", 0644, d_tracer, |
4867 | &global_trace, &tracing_free_buffer_fops); | |
4868 | ||
5452af66 FW |
4869 | trace_create_file("trace_marker", 0220, d_tracer, |
4870 | NULL, &tracing_mark_fops); | |
5bf9a1ee | 4871 | |
69abe6a5 AP |
4872 | trace_create_file("saved_cmdlines", 0444, d_tracer, |
4873 | NULL, &tracing_saved_cmdlines_fops); | |
5bf9a1ee | 4874 | |
5079f326 Z |
4875 | trace_create_file("trace_clock", 0644, d_tracer, NULL, |
4876 | &trace_clock_fops); | |
4877 | ||
499e5470 | 4878 | trace_create_file("tracing_on", 0644, d_tracer, |
348f0fc2 | 4879 | &global_trace, &rb_simple_fops); |
499e5470 | 4880 | |
bc0c38d1 | 4881 | #ifdef CONFIG_DYNAMIC_FTRACE |
5452af66 FW |
4882 | trace_create_file("dyn_ftrace_total_info", 0444, d_tracer, |
4883 | &ftrace_update_tot_cnt, &tracing_dyn_info_fops); | |
bc0c38d1 | 4884 | #endif |
b04cc6b1 | 4885 | |
5452af66 FW |
4886 | create_trace_options_dir(); |
4887 | ||
b04cc6b1 FW |
4888 | for_each_tracing_cpu(cpu) |
4889 | tracing_init_debugfs_percpu(cpu); | |
4890 | ||
b5ad384e | 4891 | return 0; |
bc0c38d1 SR |
4892 | } |
4893 | ||
3f5a54e3 SR |
4894 | static int trace_panic_handler(struct notifier_block *this, |
4895 | unsigned long event, void *unused) | |
4896 | { | |
944ac425 | 4897 | if (ftrace_dump_on_oops) |
cecbca96 | 4898 | ftrace_dump(ftrace_dump_on_oops); |
3f5a54e3 SR |
4899 | return NOTIFY_OK; |
4900 | } | |
4901 | ||
4902 | static struct notifier_block trace_panic_notifier = { | |
4903 | .notifier_call = trace_panic_handler, | |
4904 | .next = NULL, | |
4905 | .priority = 150 /* priority: INT_MAX >= x >= 0 */ | |
4906 | }; | |
4907 | ||
4908 | static int trace_die_handler(struct notifier_block *self, | |
4909 | unsigned long val, | |
4910 | void *data) | |
4911 | { | |
4912 | switch (val) { | |
4913 | case DIE_OOPS: | |
944ac425 | 4914 | if (ftrace_dump_on_oops) |
cecbca96 | 4915 | ftrace_dump(ftrace_dump_on_oops); |
3f5a54e3 SR |
4916 | break; |
4917 | default: | |
4918 | break; | |
4919 | } | |
4920 | return NOTIFY_OK; | |
4921 | } | |
4922 | ||
4923 | static struct notifier_block trace_die_notifier = { | |
4924 | .notifier_call = trace_die_handler, | |
4925 | .priority = 200 | |
4926 | }; | |
4927 | ||
4928 | /* | |
4929 | * printk is set to max of 1024, we really don't need it that big. | |
4930 | * Nothing should be printing 1000 characters anyway. | |
4931 | */ | |
4932 | #define TRACE_MAX_PRINT 1000 | |
4933 | ||
4934 | /* | |
4935 | * Define here KERN_TRACE so that we have one place to modify | |
4936 | * it if we decide to change what log level the ftrace dump | |
4937 | * should be at. | |
4938 | */ | |
428aee14 | 4939 | #define KERN_TRACE KERN_EMERG |
3f5a54e3 | 4940 | |
955b61e5 | 4941 | void |
3f5a54e3 SR |
4942 | trace_printk_seq(struct trace_seq *s) |
4943 | { | |
4944 | /* Probably should print a warning here. */ | |
4945 | if (s->len >= 1000) | |
4946 | s->len = 1000; | |
4947 | ||
4948 | /* should be zero ended, but we are paranoid. */ | |
4949 | s->buffer[s->len] = 0; | |
4950 | ||
4951 | printk(KERN_TRACE "%s", s->buffer); | |
4952 | ||
f9520750 | 4953 | trace_seq_init(s); |
3f5a54e3 SR |
4954 | } |
4955 | ||
955b61e5 JW |
4956 | void trace_init_global_iter(struct trace_iterator *iter) |
4957 | { | |
4958 | iter->tr = &global_trace; | |
4959 | iter->trace = current_trace; | |
4960 | iter->cpu_file = TRACE_PIPE_ALL_CPU; | |
4961 | } | |
4962 | ||
cecbca96 FW |
4963 | static void |
4964 | __ftrace_dump(bool disable_tracing, enum ftrace_dump_mode oops_dump_mode) | |
3f5a54e3 | 4965 | { |
445c8951 | 4966 | static arch_spinlock_t ftrace_dump_lock = |
edc35bd7 | 4967 | (arch_spinlock_t)__ARCH_SPIN_LOCK_UNLOCKED; |
3f5a54e3 SR |
4968 | /* use static because iter can be a bit big for the stack */ |
4969 | static struct trace_iterator iter; | |
cf586b61 | 4970 | unsigned int old_userobj; |
3f5a54e3 | 4971 | static int dump_ran; |
d769041f SR |
4972 | unsigned long flags; |
4973 | int cnt = 0, cpu; | |
3f5a54e3 SR |
4974 | |
4975 | /* only one dump */ | |
cd891ae0 | 4976 | local_irq_save(flags); |
0199c4e6 | 4977 | arch_spin_lock(&ftrace_dump_lock); |
3f5a54e3 SR |
4978 | if (dump_ran) |
4979 | goto out; | |
4980 | ||
4981 | dump_ran = 1; | |
4982 | ||
0ee6b6cf | 4983 | tracing_off(); |
cf586b61 | 4984 | |
e0a413f6 SR |
4985 | /* Did function tracer already get disabled? */ |
4986 | if (ftrace_is_dead()) { | |
4987 | printk("# WARNING: FUNCTION TRACING IS CORRUPTED\n"); | |
4988 | printk("# MAY BE MISSING FUNCTION EVENTS\n"); | |
4989 | } | |
4990 | ||
cf586b61 FW |
4991 | if (disable_tracing) |
4992 | ftrace_kill(); | |
3f5a54e3 | 4993 | |
955b61e5 JW |
4994 | trace_init_global_iter(&iter); |
4995 | ||
d769041f | 4996 | for_each_tracing_cpu(cpu) { |
955b61e5 | 4997 | atomic_inc(&iter.tr->data[cpu]->disabled); |
d769041f SR |
4998 | } |
4999 | ||
cf586b61 FW |
5000 | old_userobj = trace_flags & TRACE_ITER_SYM_USEROBJ; |
5001 | ||
b54d3de9 TE |
5002 | /* don't look at user memory in panic mode */ |
5003 | trace_flags &= ~TRACE_ITER_SYM_USEROBJ; | |
5004 | ||
e543ad76 | 5005 | /* Simulate the iterator */ |
3f5a54e3 SR |
5006 | iter.tr = &global_trace; |
5007 | iter.trace = current_trace; | |
cecbca96 FW |
5008 | |
5009 | switch (oops_dump_mode) { | |
5010 | case DUMP_ALL: | |
5011 | iter.cpu_file = TRACE_PIPE_ALL_CPU; | |
5012 | break; | |
5013 | case DUMP_ORIG: | |
5014 | iter.cpu_file = raw_smp_processor_id(); | |
5015 | break; | |
5016 | case DUMP_NONE: | |
5017 | goto out_enable; | |
5018 | default: | |
5019 | printk(KERN_TRACE "Bad dumping mode, switching to all CPUs dump\n"); | |
5020 | iter.cpu_file = TRACE_PIPE_ALL_CPU; | |
5021 | } | |
5022 | ||
5023 | printk(KERN_TRACE "Dumping ftrace buffer:\n"); | |
3f5a54e3 SR |
5024 | |
5025 | /* | |
5026 | * We need to stop all tracing on all CPUS to read the | |
5027 | * the next buffer. This is a bit expensive, but is | |
5028 | * not done often. We fill all what we can read, | |
5029 | * and then release the locks again. | |
5030 | */ | |
5031 | ||
3f5a54e3 SR |
5032 | while (!trace_empty(&iter)) { |
5033 | ||
5034 | if (!cnt) | |
5035 | printk(KERN_TRACE "---------------------------------\n"); | |
5036 | ||
5037 | cnt++; | |
5038 | ||
5039 | /* reset all but tr, trace, and overruns */ | |
5040 | memset(&iter.seq, 0, | |
5041 | sizeof(struct trace_iterator) - | |
5042 | offsetof(struct trace_iterator, seq)); | |
5043 | iter.iter_flags |= TRACE_FILE_LAT_FMT; | |
5044 | iter.pos = -1; | |
5045 | ||
955b61e5 | 5046 | if (trace_find_next_entry_inc(&iter) != NULL) { |
74e7ff8c LJ |
5047 | int ret; |
5048 | ||
5049 | ret = print_trace_line(&iter); | |
5050 | if (ret != TRACE_TYPE_NO_CONSUME) | |
5051 | trace_consume(&iter); | |
3f5a54e3 | 5052 | } |
b892e5c8 | 5053 | touch_nmi_watchdog(); |
3f5a54e3 SR |
5054 | |
5055 | trace_printk_seq(&iter.seq); | |
5056 | } | |
5057 | ||
5058 | if (!cnt) | |
5059 | printk(KERN_TRACE " (ftrace buffer empty)\n"); | |
5060 | else | |
5061 | printk(KERN_TRACE "---------------------------------\n"); | |
5062 | ||
cecbca96 | 5063 | out_enable: |
cf586b61 FW |
5064 | /* Re-enable tracing if requested */ |
5065 | if (!disable_tracing) { | |
5066 | trace_flags |= old_userobj; | |
5067 | ||
5068 | for_each_tracing_cpu(cpu) { | |
955b61e5 | 5069 | atomic_dec(&iter.tr->data[cpu]->disabled); |
cf586b61 FW |
5070 | } |
5071 | tracing_on(); | |
5072 | } | |
5073 | ||
3f5a54e3 | 5074 | out: |
0199c4e6 | 5075 | arch_spin_unlock(&ftrace_dump_lock); |
cd891ae0 | 5076 | local_irq_restore(flags); |
3f5a54e3 SR |
5077 | } |
5078 | ||
cf586b61 | 5079 | /* By default: disable tracing after the dump */ |
cecbca96 | 5080 | void ftrace_dump(enum ftrace_dump_mode oops_dump_mode) |
cf586b61 | 5081 | { |
cecbca96 | 5082 | __ftrace_dump(true, oops_dump_mode); |
cf586b61 | 5083 | } |
a8eecf22 | 5084 | EXPORT_SYMBOL_GPL(ftrace_dump); |
cf586b61 | 5085 | |
3928a8a2 | 5086 | __init static int tracer_alloc_buffers(void) |
bc0c38d1 | 5087 | { |
73c5162a | 5088 | int ring_buf_size; |
750912fa | 5089 | enum ring_buffer_flags rb_flags; |
4c11d7ae | 5090 | int i; |
9e01c1b7 | 5091 | int ret = -ENOMEM; |
4c11d7ae | 5092 | |
750912fa | 5093 | |
9e01c1b7 RR |
5094 | if (!alloc_cpumask_var(&tracing_buffer_mask, GFP_KERNEL)) |
5095 | goto out; | |
5096 | ||
5097 | if (!alloc_cpumask_var(&tracing_cpumask, GFP_KERNEL)) | |
5098 | goto out_free_buffer_mask; | |
4c11d7ae | 5099 | |
07d777fe SR |
5100 | /* Only allocate trace_printk buffers if a trace_printk exists */ |
5101 | if (__stop___trace_bprintk_fmt != __start___trace_bprintk_fmt) | |
5102 | trace_printk_init_buffers(); | |
5103 | ||
73c5162a SR |
5104 | /* To save memory, keep the ring buffer size to its minimum */ |
5105 | if (ring_buffer_expanded) | |
5106 | ring_buf_size = trace_buf_size; | |
5107 | else | |
5108 | ring_buf_size = 1; | |
5109 | ||
750912fa DS |
5110 | rb_flags = trace_flags & TRACE_ITER_OVERWRITE ? RB_FL_OVERWRITE : 0; |
5111 | ||
9e01c1b7 RR |
5112 | cpumask_copy(tracing_buffer_mask, cpu_possible_mask); |
5113 | cpumask_copy(tracing_cpumask, cpu_all_mask); | |
5114 | ||
5115 | /* TODO: make the number of buffers hot pluggable with CPUS */ | |
750912fa | 5116 | global_trace.buffer = ring_buffer_alloc(ring_buf_size, rb_flags); |
3928a8a2 SR |
5117 | if (!global_trace.buffer) { |
5118 | printk(KERN_ERR "tracer: failed to allocate ring buffer!\n"); | |
5119 | WARN_ON(1); | |
9e01c1b7 | 5120 | goto out_free_cpumask; |
4c11d7ae | 5121 | } |
499e5470 SR |
5122 | if (global_trace.buffer_disabled) |
5123 | tracing_off(); | |
4c11d7ae | 5124 | |
9e01c1b7 | 5125 | |
4c11d7ae | 5126 | #ifdef CONFIG_TRACER_MAX_TRACE |
750912fa | 5127 | max_tr.buffer = ring_buffer_alloc(1, rb_flags); |
3928a8a2 SR |
5128 | if (!max_tr.buffer) { |
5129 | printk(KERN_ERR "tracer: failed to allocate max ring buffer!\n"); | |
5130 | WARN_ON(1); | |
5131 | ring_buffer_free(global_trace.buffer); | |
9e01c1b7 | 5132 | goto out_free_cpumask; |
4c11d7ae | 5133 | } |
a98a3c3f | 5134 | #endif |
ab46428c | 5135 | |
4c11d7ae | 5136 | /* Allocate the first page for all buffers */ |
ab46428c | 5137 | for_each_tracing_cpu(i) { |
566b0aaf | 5138 | global_trace.data[i] = &per_cpu(global_trace_cpu, i); |
9705f69e | 5139 | max_tr.data[i] = &per_cpu(max_tr_data, i); |
4c11d7ae | 5140 | } |
438ced17 | 5141 | |
a591c73f VN |
5142 | set_buffer_entries(&global_trace, |
5143 | ring_buffer_size(global_trace.buffer, 0)); | |
438ced17 VN |
5144 | #ifdef CONFIG_TRACER_MAX_TRACE |
5145 | set_buffer_entries(&max_tr, 1); | |
5146 | #endif | |
bc0c38d1 | 5147 | |
bc0c38d1 SR |
5148 | trace_init_cmdlines(); |
5149 | ||
43a15386 | 5150 | register_tracer(&nop_trace); |
79fb0768 | 5151 | current_trace = &nop_trace; |
60a11774 SR |
5152 | /* All seems OK, enable tracing */ |
5153 | tracing_disabled = 0; | |
3928a8a2 | 5154 | |
3f5a54e3 SR |
5155 | atomic_notifier_chain_register(&panic_notifier_list, |
5156 | &trace_panic_notifier); | |
5157 | ||
5158 | register_die_notifier(&trace_die_notifier); | |
2fc1dfbe FW |
5159 | |
5160 | return 0; | |
3f5a54e3 | 5161 | |
9e01c1b7 RR |
5162 | out_free_cpumask: |
5163 | free_cpumask_var(tracing_cpumask); | |
5164 | out_free_buffer_mask: | |
5165 | free_cpumask_var(tracing_buffer_mask); | |
5166 | out: | |
5167 | return ret; | |
bc0c38d1 | 5168 | } |
b2821ae6 SR |
5169 | |
5170 | __init static int clear_boot_tracer(void) | |
5171 | { | |
5172 | /* | |
5173 | * The default tracer at boot buffer is an init section. | |
5174 | * This function is called in lateinit. If we did not | |
5175 | * find the boot tracer, then clear it out, to prevent | |
5176 | * later registration from accessing the buffer that is | |
5177 | * about to be freed. | |
5178 | */ | |
5179 | if (!default_bootup_tracer) | |
5180 | return 0; | |
5181 | ||
5182 | printk(KERN_INFO "ftrace bootup tracer '%s' not registered.\n", | |
5183 | default_bootup_tracer); | |
5184 | default_bootup_tracer = NULL; | |
5185 | ||
5186 | return 0; | |
5187 | } | |
5188 | ||
b5ad384e FW |
5189 | early_initcall(tracer_alloc_buffers); |
5190 | fs_initcall(tracer_init_debugfs); | |
b2821ae6 | 5191 | late_initcall(clear_boot_tracer); |