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 | |
6d49e352 | 12 | * Copyright (C) 2004 Nadia Yvette Chambers |
bc0c38d1 | 13 | */ |
2cadf913 | 14 | #include <linux/ring_buffer.h> |
273b281f | 15 | #include <generated/utsrelease.h> |
2cadf913 SR |
16 | #include <linux/stacktrace.h> |
17 | #include <linux/writeback.h> | |
bc0c38d1 SR |
18 | #include <linux/kallsyms.h> |
19 | #include <linux/seq_file.h> | |
3f5a54e3 | 20 | #include <linux/notifier.h> |
2cadf913 | 21 | #include <linux/irqflags.h> |
0d5c6e1c | 22 | #include <linux/irq_work.h> |
bc0c38d1 | 23 | #include <linux/debugfs.h> |
4c11d7ae | 24 | #include <linux/pagemap.h> |
bc0c38d1 SR |
25 | #include <linux/hardirq.h> |
26 | #include <linux/linkage.h> | |
27 | #include <linux/uaccess.h> | |
2cadf913 | 28 | #include <linux/kprobes.h> |
bc0c38d1 SR |
29 | #include <linux/ftrace.h> |
30 | #include <linux/module.h> | |
31 | #include <linux/percpu.h> | |
2cadf913 | 32 | #include <linux/splice.h> |
3f5a54e3 | 33 | #include <linux/kdebug.h> |
5f0c6c03 | 34 | #include <linux/string.h> |
7e53bd42 | 35 | #include <linux/rwsem.h> |
5a0e3ad6 | 36 | #include <linux/slab.h> |
bc0c38d1 SR |
37 | #include <linux/ctype.h> |
38 | #include <linux/init.h> | |
2a2cc8f7 | 39 | #include <linux/poll.h> |
b892e5c8 | 40 | #include <linux/nmi.h> |
bc0c38d1 | 41 | #include <linux/fs.h> |
86387f7e | 42 | |
bc0c38d1 | 43 | #include "trace.h" |
f0868d1e | 44 | #include "trace_output.h" |
bc0c38d1 | 45 | |
73c5162a SR |
46 | /* |
47 | * On boot up, the ring buffer is set to the minimum size, so that | |
48 | * we do not waste memory on systems that are not using tracing. | |
49 | */ | |
020e5f85 | 50 | int ring_buffer_expanded; |
73c5162a | 51 | |
8e1b82e0 FW |
52 | /* |
53 | * We need to change this state when a selftest is running. | |
ff32504f FW |
54 | * A selftest will lurk into the ring-buffer to count the |
55 | * entries inserted during the selftest although some concurrent | |
5e1607a0 | 56 | * insertions into the ring-buffer such as trace_printk could occurred |
ff32504f FW |
57 | * at the same time, giving false positive or negative results. |
58 | */ | |
8e1b82e0 | 59 | static bool __read_mostly tracing_selftest_running; |
ff32504f | 60 | |
b2821ae6 SR |
61 | /* |
62 | * If a tracer is running, we do not want to run SELFTEST. | |
63 | */ | |
020e5f85 | 64 | bool __read_mostly tracing_selftest_disabled; |
b2821ae6 | 65 | |
adf9f195 FW |
66 | /* For tracers that don't implement custom flags */ |
67 | static struct tracer_opt dummy_tracer_opt[] = { | |
68 | { } | |
69 | }; | |
70 | ||
71 | static struct tracer_flags dummy_tracer_flags = { | |
72 | .val = 0, | |
73 | .opts = dummy_tracer_opt | |
74 | }; | |
75 | ||
76 | static int dummy_set_flag(u32 old_flags, u32 bit, int set) | |
77 | { | |
78 | return 0; | |
79 | } | |
0f048701 | 80 | |
7ffbd48d SR |
81 | /* |
82 | * To prevent the comm cache from being overwritten when no | |
83 | * tracing is active, only save the comm when a trace event | |
84 | * occurred. | |
85 | */ | |
86 | static DEFINE_PER_CPU(bool, trace_cmdline_save); | |
87 | ||
0d5c6e1c SR |
88 | /* |
89 | * When a reader is waiting for data, then this variable is | |
90 | * set to true. | |
91 | */ | |
92 | static bool trace_wakeup_needed; | |
93 | ||
94 | static struct irq_work trace_work_wakeup; | |
95 | ||
0f048701 SR |
96 | /* |
97 | * Kill all tracing for good (never come back). | |
98 | * It is initialized to 1 but will turn to zero if the initialization | |
99 | * of the tracer is successful. But that is the only place that sets | |
100 | * this back to zero. | |
101 | */ | |
4fd27358 | 102 | static int tracing_disabled = 1; |
0f048701 | 103 | |
9288f99a | 104 | DEFINE_PER_CPU(int, ftrace_cpu_disabled); |
d769041f | 105 | |
955b61e5 | 106 | cpumask_var_t __read_mostly tracing_buffer_mask; |
ab46428c | 107 | |
944ac425 SR |
108 | /* |
109 | * ftrace_dump_on_oops - variable to dump ftrace buffer on oops | |
110 | * | |
111 | * If there is an oops (or kernel panic) and the ftrace_dump_on_oops | |
112 | * is set, then ftrace_dump is called. This will output the contents | |
113 | * of the ftrace buffers to the console. This is very useful for | |
114 | * capturing traces that lead to crashes and outputing it to a | |
115 | * serial console. | |
116 | * | |
117 | * It is default off, but you can enable it with either specifying | |
118 | * "ftrace_dump_on_oops" in the kernel command line, or setting | |
cecbca96 FW |
119 | * /proc/sys/kernel/ftrace_dump_on_oops |
120 | * Set 1 if you want to dump buffers of all CPUs | |
121 | * Set 2 if you want to dump the buffer of the CPU that triggered oops | |
944ac425 | 122 | */ |
cecbca96 FW |
123 | |
124 | enum ftrace_dump_mode ftrace_dump_on_oops; | |
944ac425 | 125 | |
b2821ae6 SR |
126 | static int tracing_set_tracer(const char *buf); |
127 | ||
ee6c2c1b LZ |
128 | #define MAX_TRACER_SIZE 100 |
129 | static char bootup_tracer_buf[MAX_TRACER_SIZE] __initdata; | |
b2821ae6 | 130 | static char *default_bootup_tracer; |
d9e54076 | 131 | |
1beee96b | 132 | static int __init set_cmdline_ftrace(char *str) |
d9e54076 | 133 | { |
ee6c2c1b | 134 | strncpy(bootup_tracer_buf, str, MAX_TRACER_SIZE); |
b2821ae6 | 135 | default_bootup_tracer = bootup_tracer_buf; |
73c5162a SR |
136 | /* We are using ftrace early, expand it */ |
137 | ring_buffer_expanded = 1; | |
d9e54076 PZ |
138 | return 1; |
139 | } | |
1beee96b | 140 | __setup("ftrace=", set_cmdline_ftrace); |
d9e54076 | 141 | |
944ac425 SR |
142 | static int __init set_ftrace_dump_on_oops(char *str) |
143 | { | |
cecbca96 FW |
144 | if (*str++ != '=' || !*str) { |
145 | ftrace_dump_on_oops = DUMP_ALL; | |
146 | return 1; | |
147 | } | |
148 | ||
149 | if (!strcmp("orig_cpu", str)) { | |
150 | ftrace_dump_on_oops = DUMP_ORIG; | |
151 | return 1; | |
152 | } | |
153 | ||
154 | return 0; | |
944ac425 SR |
155 | } |
156 | __setup("ftrace_dump_on_oops", set_ftrace_dump_on_oops); | |
60a11774 | 157 | |
7bcfaf54 SR |
158 | |
159 | static char trace_boot_options_buf[MAX_TRACER_SIZE] __initdata; | |
160 | static char *trace_boot_options __initdata; | |
161 | ||
162 | static int __init set_trace_boot_options(char *str) | |
163 | { | |
164 | strncpy(trace_boot_options_buf, str, MAX_TRACER_SIZE); | |
165 | trace_boot_options = trace_boot_options_buf; | |
166 | return 0; | |
167 | } | |
168 | __setup("trace_options=", set_trace_boot_options); | |
169 | ||
cf8e3474 | 170 | unsigned long long ns2usecs(cycle_t nsec) |
bc0c38d1 SR |
171 | { |
172 | nsec += 500; | |
173 | do_div(nsec, 1000); | |
174 | return nsec; | |
175 | } | |
176 | ||
4fcdae83 SR |
177 | /* |
178 | * The global_trace is the descriptor that holds the tracing | |
179 | * buffers for the live tracing. For each CPU, it contains | |
180 | * a link list of pages that will store trace entries. The | |
181 | * page descriptor of the pages in the memory is used to hold | |
182 | * the link list by linking the lru item in the page descriptor | |
183 | * to each of the pages in the buffer per CPU. | |
184 | * | |
185 | * For each active CPU there is a data field that holds the | |
186 | * pages for the buffer for that CPU. Each CPU has the same number | |
187 | * of pages allocated for its buffer. | |
188 | */ | |
bc0c38d1 SR |
189 | static struct trace_array global_trace; |
190 | ||
191 | static DEFINE_PER_CPU(struct trace_array_cpu, global_trace_cpu); | |
192 | ||
e77405ad SR |
193 | int filter_current_check_discard(struct ring_buffer *buffer, |
194 | struct ftrace_event_call *call, void *rec, | |
eb02ce01 TZ |
195 | struct ring_buffer_event *event) |
196 | { | |
e77405ad | 197 | return filter_check_discard(call, rec, buffer, event); |
eb02ce01 | 198 | } |
17c873ec | 199 | EXPORT_SYMBOL_GPL(filter_current_check_discard); |
eb02ce01 | 200 | |
37886f6a SR |
201 | cycle_t ftrace_now(int cpu) |
202 | { | |
203 | u64 ts; | |
204 | ||
205 | /* Early boot up does not have a buffer yet */ | |
206 | if (!global_trace.buffer) | |
207 | return trace_clock_local(); | |
208 | ||
209 | ts = ring_buffer_time_stamp(global_trace.buffer, cpu); | |
210 | ring_buffer_normalize_time_stamp(global_trace.buffer, cpu, &ts); | |
211 | ||
212 | return ts; | |
213 | } | |
bc0c38d1 | 214 | |
4fcdae83 SR |
215 | /* |
216 | * The max_tr is used to snapshot the global_trace when a maximum | |
217 | * latency is reached. Some tracers will use this to store a maximum | |
218 | * trace while it continues examining live traces. | |
219 | * | |
220 | * The buffers for the max_tr are set up the same as the global_trace. | |
221 | * When a snapshot is taken, the link list of the max_tr is swapped | |
222 | * with the link list of the global_trace and the buffers are reset for | |
223 | * the global_trace so the tracing can continue. | |
224 | */ | |
bc0c38d1 SR |
225 | static struct trace_array max_tr; |
226 | ||
9705f69e | 227 | static DEFINE_PER_CPU(struct trace_array_cpu, max_tr_data); |
bc0c38d1 | 228 | |
9036990d SR |
229 | int tracing_is_enabled(void) |
230 | { | |
0fb9656d | 231 | return tracing_is_on(); |
9036990d SR |
232 | } |
233 | ||
4fcdae83 | 234 | /* |
3928a8a2 SR |
235 | * trace_buf_size is the size in bytes that is allocated |
236 | * for a buffer. Note, the number of bytes is always rounded | |
237 | * to page size. | |
3f5a54e3 SR |
238 | * |
239 | * This number is purposely set to a low number of 16384. | |
240 | * If the dump on oops happens, it will be much appreciated | |
241 | * to not have to wait for all that output. Anyway this can be | |
242 | * boot time and run time configurable. | |
4fcdae83 | 243 | */ |
3928a8a2 | 244 | #define TRACE_BUF_SIZE_DEFAULT 1441792UL /* 16384 * 88 (sizeof(entry)) */ |
3f5a54e3 | 245 | |
3928a8a2 | 246 | static unsigned long trace_buf_size = TRACE_BUF_SIZE_DEFAULT; |
bc0c38d1 | 247 | |
4fcdae83 | 248 | /* trace_types holds a link list of available tracers. */ |
bc0c38d1 | 249 | static struct tracer *trace_types __read_mostly; |
4fcdae83 SR |
250 | |
251 | /* current_trace points to the tracer that is currently active */ | |
bc0c38d1 | 252 | static struct tracer *current_trace __read_mostly; |
4fcdae83 | 253 | |
4fcdae83 SR |
254 | /* |
255 | * trace_types_lock is used to protect the trace_types list. | |
4fcdae83 | 256 | */ |
bc0c38d1 | 257 | static DEFINE_MUTEX(trace_types_lock); |
4fcdae83 | 258 | |
7e53bd42 LJ |
259 | /* |
260 | * serialize the access of the ring buffer | |
261 | * | |
262 | * ring buffer serializes readers, but it is low level protection. | |
263 | * The validity of the events (which returns by ring_buffer_peek() ..etc) | |
264 | * are not protected by ring buffer. | |
265 | * | |
266 | * The content of events may become garbage if we allow other process consumes | |
267 | * these events concurrently: | |
268 | * A) the page of the consumed events may become a normal page | |
269 | * (not reader page) in ring buffer, and this page will be rewrited | |
270 | * by events producer. | |
271 | * B) The page of the consumed events may become a page for splice_read, | |
272 | * and this page will be returned to system. | |
273 | * | |
274 | * These primitives allow multi process access to different cpu ring buffer | |
275 | * concurrently. | |
276 | * | |
277 | * These primitives don't distinguish read-only and read-consume access. | |
278 | * Multi read-only access are also serialized. | |
279 | */ | |
280 | ||
281 | #ifdef CONFIG_SMP | |
282 | static DECLARE_RWSEM(all_cpu_access_lock); | |
283 | static DEFINE_PER_CPU(struct mutex, cpu_access_lock); | |
284 | ||
285 | static inline void trace_access_lock(int cpu) | |
286 | { | |
287 | if (cpu == TRACE_PIPE_ALL_CPU) { | |
288 | /* gain it for accessing the whole ring buffer. */ | |
289 | down_write(&all_cpu_access_lock); | |
290 | } else { | |
291 | /* gain it for accessing a cpu ring buffer. */ | |
292 | ||
293 | /* Firstly block other trace_access_lock(TRACE_PIPE_ALL_CPU). */ | |
294 | down_read(&all_cpu_access_lock); | |
295 | ||
296 | /* Secondly block other access to this @cpu ring buffer. */ | |
297 | mutex_lock(&per_cpu(cpu_access_lock, cpu)); | |
298 | } | |
299 | } | |
300 | ||
301 | static inline void trace_access_unlock(int cpu) | |
302 | { | |
303 | if (cpu == TRACE_PIPE_ALL_CPU) { | |
304 | up_write(&all_cpu_access_lock); | |
305 | } else { | |
306 | mutex_unlock(&per_cpu(cpu_access_lock, cpu)); | |
307 | up_read(&all_cpu_access_lock); | |
308 | } | |
309 | } | |
310 | ||
311 | static inline void trace_access_lock_init(void) | |
312 | { | |
313 | int cpu; | |
314 | ||
315 | for_each_possible_cpu(cpu) | |
316 | mutex_init(&per_cpu(cpu_access_lock, cpu)); | |
317 | } | |
318 | ||
319 | #else | |
320 | ||
321 | static DEFINE_MUTEX(access_lock); | |
322 | ||
323 | static inline void trace_access_lock(int cpu) | |
324 | { | |
325 | (void)cpu; | |
326 | mutex_lock(&access_lock); | |
327 | } | |
328 | ||
329 | static inline void trace_access_unlock(int cpu) | |
330 | { | |
331 | (void)cpu; | |
332 | mutex_unlock(&access_lock); | |
333 | } | |
334 | ||
335 | static inline void trace_access_lock_init(void) | |
336 | { | |
337 | } | |
338 | ||
339 | #endif | |
340 | ||
4fcdae83 | 341 | /* trace_wait is a waitqueue for tasks blocked on trace_poll */ |
4e655519 IM |
342 | static DECLARE_WAIT_QUEUE_HEAD(trace_wait); |
343 | ||
ee6bce52 | 344 | /* trace_flags holds trace_options default values */ |
12ef7d44 | 345 | unsigned long trace_flags = TRACE_ITER_PRINT_PARENT | TRACE_ITER_PRINTK | |
a2a16d6a | 346 | TRACE_ITER_ANNOTATE | TRACE_ITER_CONTEXT_INFO | TRACE_ITER_SLEEP_TIME | |
77271ce4 | 347 | TRACE_ITER_GRAPH_TIME | TRACE_ITER_RECORD_CMD | TRACE_ITER_OVERWRITE | |
5224c3a3 | 348 | TRACE_ITER_IRQ_INFO | TRACE_ITER_MARKERS; |
4e655519 | 349 | |
b8de7bd1 | 350 | static int trace_stop_count; |
5389f6fa | 351 | static DEFINE_RAW_SPINLOCK(tracing_start_lock); |
b8de7bd1 | 352 | |
0d5c6e1c SR |
353 | /** |
354 | * trace_wake_up - wake up tasks waiting for trace input | |
355 | * | |
356 | * Schedules a delayed work to wake up any task that is blocked on the | |
357 | * trace_wait queue. These is used with trace_poll for tasks polling the | |
358 | * trace. | |
359 | */ | |
360 | static void trace_wake_up(struct irq_work *work) | |
e7e2ee89 | 361 | { |
0d5c6e1c | 362 | wake_up_all(&trace_wait); |
e7e2ee89 | 363 | |
0d5c6e1c | 364 | } |
e7e2ee89 | 365 | |
499e5470 SR |
366 | /** |
367 | * tracing_on - enable tracing buffers | |
368 | * | |
369 | * This function enables tracing buffers that may have been | |
370 | * disabled with tracing_off. | |
371 | */ | |
372 | void tracing_on(void) | |
373 | { | |
374 | if (global_trace.buffer) | |
375 | ring_buffer_record_on(global_trace.buffer); | |
376 | /* | |
377 | * This flag is only looked at when buffers haven't been | |
378 | * allocated yet. We don't really care about the race | |
379 | * between setting this flag and actually turning | |
380 | * on the buffer. | |
381 | */ | |
382 | global_trace.buffer_disabled = 0; | |
383 | } | |
384 | EXPORT_SYMBOL_GPL(tracing_on); | |
385 | ||
386 | /** | |
387 | * tracing_off - turn off tracing buffers | |
388 | * | |
389 | * This function stops the tracing buffers from recording data. | |
390 | * It does not disable any overhead the tracers themselves may | |
391 | * be causing. This function simply causes all recording to | |
392 | * the ring buffers to fail. | |
393 | */ | |
394 | void tracing_off(void) | |
395 | { | |
396 | if (global_trace.buffer) | |
f2bf1f6f | 397 | ring_buffer_record_off(global_trace.buffer); |
499e5470 SR |
398 | /* |
399 | * This flag is only looked at when buffers haven't been | |
400 | * allocated yet. We don't really care about the race | |
401 | * between setting this flag and actually turning | |
402 | * on the buffer. | |
403 | */ | |
404 | global_trace.buffer_disabled = 1; | |
405 | } | |
406 | EXPORT_SYMBOL_GPL(tracing_off); | |
407 | ||
408 | /** | |
409 | * tracing_is_on - show state of ring buffers enabled | |
410 | */ | |
411 | int tracing_is_on(void) | |
412 | { | |
413 | if (global_trace.buffer) | |
414 | return ring_buffer_record_is_on(global_trace.buffer); | |
415 | return !global_trace.buffer_disabled; | |
416 | } | |
417 | EXPORT_SYMBOL_GPL(tracing_is_on); | |
418 | ||
3928a8a2 | 419 | static int __init set_buf_size(char *str) |
bc0c38d1 | 420 | { |
3928a8a2 | 421 | unsigned long buf_size; |
c6caeeb1 | 422 | |
bc0c38d1 SR |
423 | if (!str) |
424 | return 0; | |
9d612bef | 425 | buf_size = memparse(str, &str); |
c6caeeb1 | 426 | /* nr_entries can not be zero */ |
9d612bef | 427 | if (buf_size == 0) |
c6caeeb1 | 428 | return 0; |
3928a8a2 | 429 | trace_buf_size = buf_size; |
bc0c38d1 SR |
430 | return 1; |
431 | } | |
3928a8a2 | 432 | __setup("trace_buf_size=", set_buf_size); |
bc0c38d1 | 433 | |
0e950173 TB |
434 | static int __init set_tracing_thresh(char *str) |
435 | { | |
87abb3b1 | 436 | unsigned long threshold; |
0e950173 TB |
437 | int ret; |
438 | ||
439 | if (!str) | |
440 | return 0; | |
bcd83ea6 | 441 | ret = kstrtoul(str, 0, &threshold); |
0e950173 TB |
442 | if (ret < 0) |
443 | return 0; | |
87abb3b1 | 444 | tracing_thresh = threshold * 1000; |
0e950173 TB |
445 | return 1; |
446 | } | |
447 | __setup("tracing_thresh=", set_tracing_thresh); | |
448 | ||
57f50be1 SR |
449 | unsigned long nsecs_to_usecs(unsigned long nsecs) |
450 | { | |
451 | return nsecs / 1000; | |
452 | } | |
453 | ||
4fcdae83 | 454 | /* These must match the bit postions in trace_iterator_flags */ |
bc0c38d1 SR |
455 | static const char *trace_options[] = { |
456 | "print-parent", | |
457 | "sym-offset", | |
458 | "sym-addr", | |
459 | "verbose", | |
f9896bf3 | 460 | "raw", |
5e3ca0ec | 461 | "hex", |
cb0f12aa | 462 | "bin", |
2a2cc8f7 | 463 | "block", |
86387f7e | 464 | "stacktrace", |
5e1607a0 | 465 | "trace_printk", |
b2a866f9 | 466 | "ftrace_preempt", |
9f029e83 | 467 | "branch", |
12ef7d44 | 468 | "annotate", |
02b67518 | 469 | "userstacktrace", |
b54d3de9 | 470 | "sym-userobj", |
66896a85 | 471 | "printk-msg-only", |
c4a8e8be | 472 | "context-info", |
c032ef64 | 473 | "latency-format", |
be6f164a | 474 | "sleep-time", |
a2a16d6a | 475 | "graph-time", |
e870e9a1 | 476 | "record-cmd", |
750912fa | 477 | "overwrite", |
cf30cf67 | 478 | "disable_on_free", |
77271ce4 | 479 | "irq-info", |
5224c3a3 | 480 | "markers", |
bc0c38d1 SR |
481 | NULL |
482 | }; | |
483 | ||
5079f326 Z |
484 | static struct { |
485 | u64 (*func)(void); | |
486 | const char *name; | |
8be0709f | 487 | int in_ns; /* is this clock in nanoseconds? */ |
5079f326 | 488 | } trace_clocks[] = { |
8be0709f DS |
489 | { trace_clock_local, "local", 1 }, |
490 | { trace_clock_global, "global", 1 }, | |
491 | { trace_clock_counter, "counter", 0 }, | |
8cbd9cc6 | 492 | ARCH_TRACE_CLOCKS |
5079f326 Z |
493 | }; |
494 | ||
495 | int trace_clock_id; | |
496 | ||
b63f39ea | 497 | /* |
498 | * trace_parser_get_init - gets the buffer for trace parser | |
499 | */ | |
500 | int trace_parser_get_init(struct trace_parser *parser, int size) | |
501 | { | |
502 | memset(parser, 0, sizeof(*parser)); | |
503 | ||
504 | parser->buffer = kmalloc(size, GFP_KERNEL); | |
505 | if (!parser->buffer) | |
506 | return 1; | |
507 | ||
508 | parser->size = size; | |
509 | return 0; | |
510 | } | |
511 | ||
512 | /* | |
513 | * trace_parser_put - frees the buffer for trace parser | |
514 | */ | |
515 | void trace_parser_put(struct trace_parser *parser) | |
516 | { | |
517 | kfree(parser->buffer); | |
518 | } | |
519 | ||
520 | /* | |
521 | * trace_get_user - reads the user input string separated by space | |
522 | * (matched by isspace(ch)) | |
523 | * | |
524 | * For each string found the 'struct trace_parser' is updated, | |
525 | * and the function returns. | |
526 | * | |
527 | * Returns number of bytes read. | |
528 | * | |
529 | * See kernel/trace/trace.h for 'struct trace_parser' details. | |
530 | */ | |
531 | int trace_get_user(struct trace_parser *parser, const char __user *ubuf, | |
532 | size_t cnt, loff_t *ppos) | |
533 | { | |
534 | char ch; | |
535 | size_t read = 0; | |
536 | ssize_t ret; | |
537 | ||
538 | if (!*ppos) | |
539 | trace_parser_clear(parser); | |
540 | ||
541 | ret = get_user(ch, ubuf++); | |
542 | if (ret) | |
543 | goto out; | |
544 | ||
545 | read++; | |
546 | cnt--; | |
547 | ||
548 | /* | |
549 | * The parser is not finished with the last write, | |
550 | * continue reading the user input without skipping spaces. | |
551 | */ | |
552 | if (!parser->cont) { | |
553 | /* skip white space */ | |
554 | while (cnt && isspace(ch)) { | |
555 | ret = get_user(ch, ubuf++); | |
556 | if (ret) | |
557 | goto out; | |
558 | read++; | |
559 | cnt--; | |
560 | } | |
561 | ||
562 | /* only spaces were written */ | |
563 | if (isspace(ch)) { | |
564 | *ppos += read; | |
565 | ret = read; | |
566 | goto out; | |
567 | } | |
568 | ||
569 | parser->idx = 0; | |
570 | } | |
571 | ||
572 | /* read the non-space input */ | |
573 | while (cnt && !isspace(ch)) { | |
3c235a33 | 574 | if (parser->idx < parser->size - 1) |
b63f39ea | 575 | parser->buffer[parser->idx++] = ch; |
576 | else { | |
577 | ret = -EINVAL; | |
578 | goto out; | |
579 | } | |
580 | ret = get_user(ch, ubuf++); | |
581 | if (ret) | |
582 | goto out; | |
583 | read++; | |
584 | cnt--; | |
585 | } | |
586 | ||
587 | /* We either got finished input or we have to wait for another call. */ | |
588 | if (isspace(ch)) { | |
589 | parser->buffer[parser->idx] = 0; | |
590 | parser->cont = false; | |
591 | } else { | |
592 | parser->cont = true; | |
593 | parser->buffer[parser->idx++] = ch; | |
594 | } | |
595 | ||
596 | *ppos += read; | |
597 | ret = read; | |
598 | ||
599 | out: | |
600 | return ret; | |
601 | } | |
602 | ||
6c6c2796 PP |
603 | ssize_t trace_seq_to_user(struct trace_seq *s, char __user *ubuf, size_t cnt) |
604 | { | |
605 | int len; | |
606 | int ret; | |
607 | ||
2dc5d12b SR |
608 | if (!cnt) |
609 | return 0; | |
610 | ||
6c6c2796 PP |
611 | if (s->len <= s->readpos) |
612 | return -EBUSY; | |
613 | ||
614 | len = s->len - s->readpos; | |
615 | if (cnt > len) | |
616 | cnt = len; | |
617 | ret = copy_to_user(ubuf, s->buffer + s->readpos, cnt); | |
2dc5d12b | 618 | if (ret == cnt) |
6c6c2796 PP |
619 | return -EFAULT; |
620 | ||
2dc5d12b SR |
621 | cnt -= ret; |
622 | ||
e74da523 | 623 | s->readpos += cnt; |
6c6c2796 | 624 | return cnt; |
214023c3 SR |
625 | } |
626 | ||
b8b94265 | 627 | static ssize_t trace_seq_to_buffer(struct trace_seq *s, void *buf, size_t cnt) |
3c56819b EGM |
628 | { |
629 | int len; | |
3c56819b EGM |
630 | |
631 | if (s->len <= s->readpos) | |
632 | return -EBUSY; | |
633 | ||
634 | len = s->len - s->readpos; | |
635 | if (cnt > len) | |
636 | cnt = len; | |
5a26c8f0 | 637 | memcpy(buf, s->buffer + s->readpos, cnt); |
3c56819b | 638 | |
e74da523 | 639 | s->readpos += cnt; |
3c56819b EGM |
640 | return cnt; |
641 | } | |
642 | ||
5d4a9dba SR |
643 | /* |
644 | * ftrace_max_lock is used to protect the swapping of buffers | |
645 | * when taking a max snapshot. The buffers themselves are | |
646 | * protected by per_cpu spinlocks. But the action of the swap | |
647 | * needs its own lock. | |
648 | * | |
445c8951 | 649 | * This is defined as a arch_spinlock_t in order to help |
5d4a9dba SR |
650 | * with performance when lockdep debugging is enabled. |
651 | * | |
652 | * It is also used in other places outside the update_max_tr | |
653 | * so it needs to be defined outside of the | |
654 | * CONFIG_TRACER_MAX_TRACE. | |
655 | */ | |
445c8951 | 656 | static arch_spinlock_t ftrace_max_lock = |
edc35bd7 | 657 | (arch_spinlock_t)__ARCH_SPIN_LOCK_UNLOCKED; |
5d4a9dba | 658 | |
0e950173 TB |
659 | unsigned long __read_mostly tracing_thresh; |
660 | ||
5d4a9dba SR |
661 | #ifdef CONFIG_TRACER_MAX_TRACE |
662 | unsigned long __read_mostly tracing_max_latency; | |
5d4a9dba SR |
663 | |
664 | /* | |
665 | * Copy the new maximum trace into the separate maximum-trace | |
666 | * structure. (this way the maximum trace is permanently saved, | |
667 | * for later retrieval via /sys/kernel/debug/tracing/latency_trace) | |
668 | */ | |
669 | static void | |
670 | __update_max_tr(struct trace_array *tr, struct task_struct *tsk, int cpu) | |
671 | { | |
672 | struct trace_array_cpu *data = tr->data[cpu]; | |
1acaa1b2 | 673 | struct trace_array_cpu *max_data; |
5d4a9dba SR |
674 | |
675 | max_tr.cpu = cpu; | |
676 | max_tr.time_start = data->preempt_timestamp; | |
677 | ||
8248ac05 SR |
678 | max_data = max_tr.data[cpu]; |
679 | max_data->saved_latency = tracing_max_latency; | |
680 | max_data->critical_start = data->critical_start; | |
681 | max_data->critical_end = data->critical_end; | |
5d4a9dba | 682 | |
1acaa1b2 | 683 | memcpy(max_data->comm, tsk->comm, TASK_COMM_LEN); |
8248ac05 SR |
684 | max_data->pid = tsk->pid; |
685 | max_data->uid = task_uid(tsk); | |
686 | max_data->nice = tsk->static_prio - 20 - MAX_RT_PRIO; | |
687 | max_data->policy = tsk->policy; | |
688 | max_data->rt_priority = tsk->rt_priority; | |
5d4a9dba SR |
689 | |
690 | /* record this tasks comm */ | |
691 | tracing_record_cmdline(tsk); | |
692 | } | |
693 | ||
4fcdae83 SR |
694 | /** |
695 | * update_max_tr - snapshot all trace buffers from global_trace to max_tr | |
696 | * @tr: tracer | |
697 | * @tsk: the task with the latency | |
698 | * @cpu: The cpu that initiated the trace. | |
699 | * | |
700 | * Flip the buffers between the @tr and the max_tr and record information | |
701 | * about which task was the cause of this latency. | |
702 | */ | |
e309b41d | 703 | void |
bc0c38d1 SR |
704 | update_max_tr(struct trace_array *tr, struct task_struct *tsk, int cpu) |
705 | { | |
3928a8a2 | 706 | struct ring_buffer *buf = tr->buffer; |
bc0c38d1 | 707 | |
b8de7bd1 SR |
708 | if (trace_stop_count) |
709 | return; | |
710 | ||
4c11d7ae | 711 | WARN_ON_ONCE(!irqs_disabled()); |
ef710e10 KM |
712 | if (!current_trace->use_max_tr) { |
713 | WARN_ON_ONCE(1); | |
714 | return; | |
715 | } | |
0199c4e6 | 716 | arch_spin_lock(&ftrace_max_lock); |
3928a8a2 SR |
717 | |
718 | tr->buffer = max_tr.buffer; | |
719 | max_tr.buffer = buf; | |
720 | ||
bc0c38d1 | 721 | __update_max_tr(tr, tsk, cpu); |
0199c4e6 | 722 | arch_spin_unlock(&ftrace_max_lock); |
bc0c38d1 SR |
723 | } |
724 | ||
725 | /** | |
726 | * update_max_tr_single - only copy one trace over, and reset the rest | |
727 | * @tr - tracer | |
728 | * @tsk - task with the latency | |
729 | * @cpu - the cpu of the buffer to copy. | |
4fcdae83 SR |
730 | * |
731 | * Flip the trace of a single CPU buffer between the @tr and the max_tr. | |
bc0c38d1 | 732 | */ |
e309b41d | 733 | void |
bc0c38d1 SR |
734 | update_max_tr_single(struct trace_array *tr, struct task_struct *tsk, int cpu) |
735 | { | |
3928a8a2 | 736 | int ret; |
bc0c38d1 | 737 | |
b8de7bd1 SR |
738 | if (trace_stop_count) |
739 | return; | |
740 | ||
4c11d7ae | 741 | WARN_ON_ONCE(!irqs_disabled()); |
ef710e10 KM |
742 | if (!current_trace->use_max_tr) { |
743 | WARN_ON_ONCE(1); | |
744 | return; | |
745 | } | |
746 | ||
0199c4e6 | 747 | arch_spin_lock(&ftrace_max_lock); |
bc0c38d1 | 748 | |
3928a8a2 SR |
749 | ret = ring_buffer_swap_cpu(max_tr.buffer, tr->buffer, cpu); |
750 | ||
e8165dbb SR |
751 | if (ret == -EBUSY) { |
752 | /* | |
753 | * We failed to swap the buffer due to a commit taking | |
754 | * place on this CPU. We fail to record, but we reset | |
755 | * the max trace buffer (no one writes directly to it) | |
756 | * and flag that it failed. | |
757 | */ | |
758 | trace_array_printk(&max_tr, _THIS_IP_, | |
759 | "Failed to swap buffers due to commit in progress\n"); | |
760 | } | |
761 | ||
e8165dbb | 762 | WARN_ON_ONCE(ret && ret != -EAGAIN && ret != -EBUSY); |
bc0c38d1 SR |
763 | |
764 | __update_max_tr(tr, tsk, cpu); | |
0199c4e6 | 765 | arch_spin_unlock(&ftrace_max_lock); |
bc0c38d1 | 766 | } |
5d4a9dba | 767 | #endif /* CONFIG_TRACER_MAX_TRACE */ |
bc0c38d1 | 768 | |
0d5c6e1c SR |
769 | static void default_wait_pipe(struct trace_iterator *iter) |
770 | { | |
771 | DEFINE_WAIT(wait); | |
772 | ||
773 | prepare_to_wait(&trace_wait, &wait, TASK_INTERRUPTIBLE); | |
774 | ||
775 | /* | |
776 | * The events can happen in critical sections where | |
777 | * checking a work queue can cause deadlocks. | |
778 | * After adding a task to the queue, this flag is set | |
779 | * only to notify events to try to wake up the queue | |
780 | * using irq_work. | |
781 | * | |
782 | * We don't clear it even if the buffer is no longer | |
783 | * empty. The flag only causes the next event to run | |
784 | * irq_work to do the work queue wake up. The worse | |
785 | * that can happen if we race with !trace_empty() is that | |
786 | * an event will cause an irq_work to try to wake up | |
787 | * an empty queue. | |
788 | * | |
789 | * There's no reason to protect this flag either, as | |
790 | * the work queue and irq_work logic will do the necessary | |
791 | * synchronization for the wake ups. The only thing | |
792 | * that is necessary is that the wake up happens after | |
793 | * a task has been queued. It's OK for spurious wake ups. | |
794 | */ | |
795 | trace_wakeup_needed = true; | |
796 | ||
797 | if (trace_empty(iter)) | |
798 | schedule(); | |
799 | ||
800 | finish_wait(&trace_wait, &wait); | |
801 | } | |
802 | ||
4fcdae83 SR |
803 | /** |
804 | * register_tracer - register a tracer with the ftrace system. | |
805 | * @type - the plugin for the tracer | |
806 | * | |
807 | * Register a new plugin tracer. | |
808 | */ | |
bc0c38d1 SR |
809 | int register_tracer(struct tracer *type) |
810 | { | |
811 | struct tracer *t; | |
bc0c38d1 SR |
812 | int ret = 0; |
813 | ||
814 | if (!type->name) { | |
815 | pr_info("Tracer must have a name\n"); | |
816 | return -1; | |
817 | } | |
818 | ||
24a461d5 | 819 | if (strlen(type->name) >= MAX_TRACER_SIZE) { |
ee6c2c1b LZ |
820 | pr_info("Tracer has a name longer than %d\n", MAX_TRACER_SIZE); |
821 | return -1; | |
822 | } | |
823 | ||
bc0c38d1 | 824 | mutex_lock(&trace_types_lock); |
86fa2f60 | 825 | |
8e1b82e0 FW |
826 | tracing_selftest_running = true; |
827 | ||
bc0c38d1 SR |
828 | for (t = trace_types; t; t = t->next) { |
829 | if (strcmp(type->name, t->name) == 0) { | |
830 | /* already found */ | |
ee6c2c1b | 831 | pr_info("Tracer %s already registered\n", |
bc0c38d1 SR |
832 | type->name); |
833 | ret = -1; | |
834 | goto out; | |
835 | } | |
836 | } | |
837 | ||
adf9f195 FW |
838 | if (!type->set_flag) |
839 | type->set_flag = &dummy_set_flag; | |
840 | if (!type->flags) | |
841 | type->flags = &dummy_tracer_flags; | |
842 | else | |
843 | if (!type->flags->opts) | |
844 | type->flags->opts = dummy_tracer_opt; | |
6eaaa5d5 FW |
845 | if (!type->wait_pipe) |
846 | type->wait_pipe = default_wait_pipe; | |
847 | ||
adf9f195 | 848 | |
60a11774 | 849 | #ifdef CONFIG_FTRACE_STARTUP_TEST |
b2821ae6 | 850 | if (type->selftest && !tracing_selftest_disabled) { |
60a11774 | 851 | struct tracer *saved_tracer = current_trace; |
60a11774 | 852 | struct trace_array *tr = &global_trace; |
ff32504f | 853 | |
60a11774 SR |
854 | /* |
855 | * Run a selftest on this tracer. | |
856 | * Here we reset the trace buffer, and set the current | |
857 | * tracer to be this tracer. The tracer can then run some | |
858 | * internal tracing to verify that everything is in order. | |
859 | * If we fail, we do not register this tracer. | |
860 | */ | |
76f0d073 | 861 | tracing_reset_online_cpus(tr); |
86fa2f60 | 862 | |
60a11774 | 863 | current_trace = type; |
4a0b1665 SR |
864 | |
865 | /* If we expanded the buffers, make sure the max is expanded too */ | |
866 | if (ring_buffer_expanded && type->use_max_tr) | |
438ced17 VN |
867 | ring_buffer_resize(max_tr.buffer, trace_buf_size, |
868 | RING_BUFFER_ALL_CPUS); | |
4a0b1665 | 869 | |
60a11774 SR |
870 | /* the test is responsible for initializing and enabling */ |
871 | pr_info("Testing tracer %s: ", type->name); | |
872 | ret = type->selftest(type, tr); | |
873 | /* the test is responsible for resetting too */ | |
874 | current_trace = saved_tracer; | |
60a11774 SR |
875 | if (ret) { |
876 | printk(KERN_CONT "FAILED!\n"); | |
0be61ebc SR |
877 | /* Add the warning after printing 'FAILED' */ |
878 | WARN_ON(1); | |
60a11774 SR |
879 | goto out; |
880 | } | |
1d4db00a | 881 | /* Only reset on passing, to avoid touching corrupted buffers */ |
76f0d073 | 882 | tracing_reset_online_cpus(tr); |
86fa2f60 | 883 | |
4a0b1665 SR |
884 | /* Shrink the max buffer again */ |
885 | if (ring_buffer_expanded && type->use_max_tr) | |
438ced17 VN |
886 | ring_buffer_resize(max_tr.buffer, 1, |
887 | RING_BUFFER_ALL_CPUS); | |
4a0b1665 | 888 | |
60a11774 SR |
889 | printk(KERN_CONT "PASSED\n"); |
890 | } | |
891 | #endif | |
892 | ||
bc0c38d1 SR |
893 | type->next = trace_types; |
894 | trace_types = type; | |
60a11774 | 895 | |
bc0c38d1 | 896 | out: |
8e1b82e0 | 897 | tracing_selftest_running = false; |
bc0c38d1 SR |
898 | mutex_unlock(&trace_types_lock); |
899 | ||
dac74940 SR |
900 | if (ret || !default_bootup_tracer) |
901 | goto out_unlock; | |
902 | ||
ee6c2c1b | 903 | if (strncmp(default_bootup_tracer, type->name, MAX_TRACER_SIZE)) |
dac74940 SR |
904 | goto out_unlock; |
905 | ||
906 | printk(KERN_INFO "Starting tracer '%s'\n", type->name); | |
907 | /* Do we want this tracer to start on bootup? */ | |
908 | tracing_set_tracer(type->name); | |
909 | default_bootup_tracer = NULL; | |
910 | /* disable other selftests, since this will break it. */ | |
911 | tracing_selftest_disabled = 1; | |
b2821ae6 | 912 | #ifdef CONFIG_FTRACE_STARTUP_TEST |
dac74940 SR |
913 | printk(KERN_INFO "Disabling FTRACE selftests due to running tracer '%s'\n", |
914 | type->name); | |
b2821ae6 | 915 | #endif |
b2821ae6 | 916 | |
dac74940 | 917 | out_unlock: |
bc0c38d1 SR |
918 | return ret; |
919 | } | |
920 | ||
f633903a SR |
921 | void tracing_reset(struct trace_array *tr, int cpu) |
922 | { | |
923 | struct ring_buffer *buffer = tr->buffer; | |
924 | ||
a5416411 HT |
925 | if (!buffer) |
926 | return; | |
927 | ||
f633903a SR |
928 | ring_buffer_record_disable(buffer); |
929 | ||
930 | /* Make sure all commits have finished */ | |
931 | synchronize_sched(); | |
68179686 | 932 | ring_buffer_reset_cpu(buffer, cpu); |
f633903a SR |
933 | |
934 | ring_buffer_record_enable(buffer); | |
935 | } | |
936 | ||
213cc060 PE |
937 | void tracing_reset_online_cpus(struct trace_array *tr) |
938 | { | |
621968cd | 939 | struct ring_buffer *buffer = tr->buffer; |
213cc060 PE |
940 | int cpu; |
941 | ||
a5416411 HT |
942 | if (!buffer) |
943 | return; | |
944 | ||
621968cd SR |
945 | ring_buffer_record_disable(buffer); |
946 | ||
947 | /* Make sure all commits have finished */ | |
948 | synchronize_sched(); | |
949 | ||
213cc060 PE |
950 | tr->time_start = ftrace_now(tr->cpu); |
951 | ||
952 | for_each_online_cpu(cpu) | |
68179686 | 953 | ring_buffer_reset_cpu(buffer, cpu); |
621968cd SR |
954 | |
955 | ring_buffer_record_enable(buffer); | |
213cc060 PE |
956 | } |
957 | ||
9456f0fa SR |
958 | void tracing_reset_current(int cpu) |
959 | { | |
960 | tracing_reset(&global_trace, cpu); | |
961 | } | |
962 | ||
963 | void tracing_reset_current_online_cpus(void) | |
964 | { | |
965 | tracing_reset_online_cpus(&global_trace); | |
966 | } | |
967 | ||
bc0c38d1 | 968 | #define SAVED_CMDLINES 128 |
2c7eea4c | 969 | #define NO_CMDLINE_MAP UINT_MAX |
bc0c38d1 SR |
970 | static unsigned map_pid_to_cmdline[PID_MAX_DEFAULT+1]; |
971 | static unsigned map_cmdline_to_pid[SAVED_CMDLINES]; | |
972 | static char saved_cmdlines[SAVED_CMDLINES][TASK_COMM_LEN]; | |
973 | static int cmdline_idx; | |
edc35bd7 | 974 | static arch_spinlock_t trace_cmdline_lock = __ARCH_SPIN_LOCK_UNLOCKED; |
25b0b44a | 975 | |
25b0b44a | 976 | /* temporary disable recording */ |
4fd27358 | 977 | static atomic_t trace_record_cmdline_disabled __read_mostly; |
bc0c38d1 SR |
978 | |
979 | static void trace_init_cmdlines(void) | |
980 | { | |
2c7eea4c TG |
981 | memset(&map_pid_to_cmdline, NO_CMDLINE_MAP, sizeof(map_pid_to_cmdline)); |
982 | memset(&map_cmdline_to_pid, NO_CMDLINE_MAP, sizeof(map_cmdline_to_pid)); | |
bc0c38d1 SR |
983 | cmdline_idx = 0; |
984 | } | |
985 | ||
b5130b1e CE |
986 | int is_tracing_stopped(void) |
987 | { | |
988 | return trace_stop_count; | |
989 | } | |
990 | ||
69bb54ec SR |
991 | /** |
992 | * ftrace_off_permanent - disable all ftrace code permanently | |
993 | * | |
994 | * This should only be called when a serious anomally has | |
995 | * been detected. This will turn off the function tracing, | |
996 | * ring buffers, and other tracing utilites. It takes no | |
997 | * locks and can be called from any context. | |
998 | */ | |
999 | void ftrace_off_permanent(void) | |
1000 | { | |
1001 | tracing_disabled = 1; | |
1002 | ftrace_stop(); | |
1003 | tracing_off_permanent(); | |
1004 | } | |
1005 | ||
0f048701 SR |
1006 | /** |
1007 | * tracing_start - quick start of the tracer | |
1008 | * | |
1009 | * If tracing is enabled but was stopped by tracing_stop, | |
1010 | * this will start the tracer back up. | |
1011 | */ | |
1012 | void tracing_start(void) | |
1013 | { | |
1014 | struct ring_buffer *buffer; | |
1015 | unsigned long flags; | |
1016 | ||
1017 | if (tracing_disabled) | |
1018 | return; | |
1019 | ||
5389f6fa | 1020 | raw_spin_lock_irqsave(&tracing_start_lock, flags); |
b06a8301 SR |
1021 | if (--trace_stop_count) { |
1022 | if (trace_stop_count < 0) { | |
1023 | /* Someone screwed up their debugging */ | |
1024 | WARN_ON_ONCE(1); | |
1025 | trace_stop_count = 0; | |
1026 | } | |
0f048701 SR |
1027 | goto out; |
1028 | } | |
1029 | ||
a2f80714 SR |
1030 | /* Prevent the buffers from switching */ |
1031 | arch_spin_lock(&ftrace_max_lock); | |
0f048701 SR |
1032 | |
1033 | buffer = global_trace.buffer; | |
1034 | if (buffer) | |
1035 | ring_buffer_record_enable(buffer); | |
1036 | ||
1037 | buffer = max_tr.buffer; | |
1038 | if (buffer) | |
1039 | ring_buffer_record_enable(buffer); | |
1040 | ||
a2f80714 SR |
1041 | arch_spin_unlock(&ftrace_max_lock); |
1042 | ||
0f048701 SR |
1043 | ftrace_start(); |
1044 | out: | |
5389f6fa | 1045 | raw_spin_unlock_irqrestore(&tracing_start_lock, flags); |
0f048701 SR |
1046 | } |
1047 | ||
1048 | /** | |
1049 | * tracing_stop - quick stop of the tracer | |
1050 | * | |
1051 | * Light weight way to stop tracing. Use in conjunction with | |
1052 | * tracing_start. | |
1053 | */ | |
1054 | void tracing_stop(void) | |
1055 | { | |
1056 | struct ring_buffer *buffer; | |
1057 | unsigned long flags; | |
1058 | ||
1059 | ftrace_stop(); | |
5389f6fa | 1060 | raw_spin_lock_irqsave(&tracing_start_lock, flags); |
0f048701 SR |
1061 | if (trace_stop_count++) |
1062 | goto out; | |
1063 | ||
a2f80714 SR |
1064 | /* Prevent the buffers from switching */ |
1065 | arch_spin_lock(&ftrace_max_lock); | |
1066 | ||
0f048701 SR |
1067 | buffer = global_trace.buffer; |
1068 | if (buffer) | |
1069 | ring_buffer_record_disable(buffer); | |
1070 | ||
1071 | buffer = max_tr.buffer; | |
1072 | if (buffer) | |
1073 | ring_buffer_record_disable(buffer); | |
1074 | ||
a2f80714 SR |
1075 | arch_spin_unlock(&ftrace_max_lock); |
1076 | ||
0f048701 | 1077 | out: |
5389f6fa | 1078 | raw_spin_unlock_irqrestore(&tracing_start_lock, flags); |
0f048701 SR |
1079 | } |
1080 | ||
e309b41d | 1081 | void trace_stop_cmdline_recording(void); |
bc0c38d1 | 1082 | |
e309b41d | 1083 | static void trace_save_cmdline(struct task_struct *tsk) |
bc0c38d1 | 1084 | { |
a635cf04 | 1085 | unsigned pid, idx; |
bc0c38d1 SR |
1086 | |
1087 | if (!tsk->pid || unlikely(tsk->pid > PID_MAX_DEFAULT)) | |
1088 | return; | |
1089 | ||
1090 | /* | |
1091 | * It's not the end of the world if we don't get | |
1092 | * the lock, but we also don't want to spin | |
1093 | * nor do we want to disable interrupts, | |
1094 | * so if we miss here, then better luck next time. | |
1095 | */ | |
0199c4e6 | 1096 | if (!arch_spin_trylock(&trace_cmdline_lock)) |
bc0c38d1 SR |
1097 | return; |
1098 | ||
1099 | idx = map_pid_to_cmdline[tsk->pid]; | |
2c7eea4c | 1100 | if (idx == NO_CMDLINE_MAP) { |
bc0c38d1 SR |
1101 | idx = (cmdline_idx + 1) % SAVED_CMDLINES; |
1102 | ||
a635cf04 CE |
1103 | /* |
1104 | * Check whether the cmdline buffer at idx has a pid | |
1105 | * mapped. We are going to overwrite that entry so we | |
1106 | * need to clear the map_pid_to_cmdline. Otherwise we | |
1107 | * would read the new comm for the old pid. | |
1108 | */ | |
1109 | pid = map_cmdline_to_pid[idx]; | |
1110 | if (pid != NO_CMDLINE_MAP) | |
1111 | map_pid_to_cmdline[pid] = NO_CMDLINE_MAP; | |
bc0c38d1 | 1112 | |
a635cf04 | 1113 | map_cmdline_to_pid[idx] = tsk->pid; |
bc0c38d1 SR |
1114 | map_pid_to_cmdline[tsk->pid] = idx; |
1115 | ||
1116 | cmdline_idx = idx; | |
1117 | } | |
1118 | ||
1119 | memcpy(&saved_cmdlines[idx], tsk->comm, TASK_COMM_LEN); | |
1120 | ||
0199c4e6 | 1121 | arch_spin_unlock(&trace_cmdline_lock); |
bc0c38d1 SR |
1122 | } |
1123 | ||
4ca53085 | 1124 | void trace_find_cmdline(int pid, char comm[]) |
bc0c38d1 | 1125 | { |
bc0c38d1 SR |
1126 | unsigned map; |
1127 | ||
4ca53085 SR |
1128 | if (!pid) { |
1129 | strcpy(comm, "<idle>"); | |
1130 | return; | |
1131 | } | |
bc0c38d1 | 1132 | |
74bf4076 SR |
1133 | if (WARN_ON_ONCE(pid < 0)) { |
1134 | strcpy(comm, "<XXX>"); | |
1135 | return; | |
1136 | } | |
1137 | ||
4ca53085 SR |
1138 | if (pid > PID_MAX_DEFAULT) { |
1139 | strcpy(comm, "<...>"); | |
1140 | return; | |
1141 | } | |
bc0c38d1 | 1142 | |
5b6045a9 | 1143 | preempt_disable(); |
0199c4e6 | 1144 | arch_spin_lock(&trace_cmdline_lock); |
bc0c38d1 | 1145 | map = map_pid_to_cmdline[pid]; |
50d88758 TG |
1146 | if (map != NO_CMDLINE_MAP) |
1147 | strcpy(comm, saved_cmdlines[map]); | |
1148 | else | |
1149 | strcpy(comm, "<...>"); | |
bc0c38d1 | 1150 | |
0199c4e6 | 1151 | arch_spin_unlock(&trace_cmdline_lock); |
5b6045a9 | 1152 | preempt_enable(); |
bc0c38d1 SR |
1153 | } |
1154 | ||
e309b41d | 1155 | void tracing_record_cmdline(struct task_struct *tsk) |
bc0c38d1 | 1156 | { |
0fb9656d | 1157 | if (atomic_read(&trace_record_cmdline_disabled) || !tracing_is_on()) |
bc0c38d1 SR |
1158 | return; |
1159 | ||
7ffbd48d SR |
1160 | if (!__this_cpu_read(trace_cmdline_save)) |
1161 | return; | |
1162 | ||
1163 | __this_cpu_write(trace_cmdline_save, false); | |
1164 | ||
bc0c38d1 SR |
1165 | trace_save_cmdline(tsk); |
1166 | } | |
1167 | ||
45dcd8b8 | 1168 | void |
38697053 SR |
1169 | tracing_generic_entry_update(struct trace_entry *entry, unsigned long flags, |
1170 | int pc) | |
bc0c38d1 SR |
1171 | { |
1172 | struct task_struct *tsk = current; | |
bc0c38d1 | 1173 | |
777e208d SR |
1174 | entry->preempt_count = pc & 0xff; |
1175 | entry->pid = (tsk) ? tsk->pid : 0; | |
1176 | entry->flags = | |
9244489a | 1177 | #ifdef CONFIG_TRACE_IRQFLAGS_SUPPORT |
2e2ca155 | 1178 | (irqs_disabled_flags(flags) ? TRACE_FLAG_IRQS_OFF : 0) | |
9244489a SR |
1179 | #else |
1180 | TRACE_FLAG_IRQS_NOSUPPORT | | |
1181 | #endif | |
bc0c38d1 SR |
1182 | ((pc & HARDIRQ_MASK) ? TRACE_FLAG_HARDIRQ : 0) | |
1183 | ((pc & SOFTIRQ_MASK) ? TRACE_FLAG_SOFTIRQ : 0) | | |
1184 | (need_resched() ? TRACE_FLAG_NEED_RESCHED : 0); | |
1185 | } | |
f413cdb8 | 1186 | EXPORT_SYMBOL_GPL(tracing_generic_entry_update); |
bc0c38d1 | 1187 | |
e77405ad SR |
1188 | struct ring_buffer_event * |
1189 | trace_buffer_lock_reserve(struct ring_buffer *buffer, | |
1190 | int type, | |
1191 | unsigned long len, | |
1192 | unsigned long flags, int pc) | |
51a763dd ACM |
1193 | { |
1194 | struct ring_buffer_event *event; | |
1195 | ||
e77405ad | 1196 | event = ring_buffer_lock_reserve(buffer, len); |
51a763dd ACM |
1197 | if (event != NULL) { |
1198 | struct trace_entry *ent = ring_buffer_event_data(event); | |
1199 | ||
1200 | tracing_generic_entry_update(ent, flags, pc); | |
1201 | ent->type = type; | |
1202 | } | |
1203 | ||
1204 | return event; | |
1205 | } | |
51a763dd | 1206 | |
7ffbd48d SR |
1207 | void |
1208 | __buffer_unlock_commit(struct ring_buffer *buffer, struct ring_buffer_event *event) | |
1209 | { | |
1210 | __this_cpu_write(trace_cmdline_save, true); | |
0d5c6e1c SR |
1211 | if (trace_wakeup_needed) { |
1212 | trace_wakeup_needed = false; | |
1213 | /* irq_work_queue() supplies it's own memory barriers */ | |
1214 | irq_work_queue(&trace_work_wakeup); | |
1215 | } | |
7ffbd48d SR |
1216 | ring_buffer_unlock_commit(buffer, event); |
1217 | } | |
1218 | ||
e77405ad SR |
1219 | static inline void |
1220 | __trace_buffer_unlock_commit(struct ring_buffer *buffer, | |
1221 | struct ring_buffer_event *event, | |
0d5c6e1c | 1222 | unsigned long flags, int pc) |
51a763dd | 1223 | { |
7ffbd48d | 1224 | __buffer_unlock_commit(buffer, event); |
51a763dd | 1225 | |
e77405ad SR |
1226 | ftrace_trace_stack(buffer, flags, 6, pc); |
1227 | ftrace_trace_userstack(buffer, flags, pc); | |
07edf712 FW |
1228 | } |
1229 | ||
e77405ad SR |
1230 | void trace_buffer_unlock_commit(struct ring_buffer *buffer, |
1231 | struct ring_buffer_event *event, | |
1232 | unsigned long flags, int pc) | |
07edf712 | 1233 | { |
0d5c6e1c | 1234 | __trace_buffer_unlock_commit(buffer, event, flags, pc); |
51a763dd | 1235 | } |
0d5c6e1c | 1236 | EXPORT_SYMBOL_GPL(trace_buffer_unlock_commit); |
51a763dd | 1237 | |
ef5580d0 | 1238 | struct ring_buffer_event * |
e77405ad SR |
1239 | trace_current_buffer_lock_reserve(struct ring_buffer **current_rb, |
1240 | int type, unsigned long len, | |
ef5580d0 SR |
1241 | unsigned long flags, int pc) |
1242 | { | |
e77405ad SR |
1243 | *current_rb = global_trace.buffer; |
1244 | return trace_buffer_lock_reserve(*current_rb, | |
ef5580d0 SR |
1245 | type, len, flags, pc); |
1246 | } | |
94487d6d | 1247 | EXPORT_SYMBOL_GPL(trace_current_buffer_lock_reserve); |
ef5580d0 | 1248 | |
e77405ad SR |
1249 | void trace_current_buffer_unlock_commit(struct ring_buffer *buffer, |
1250 | struct ring_buffer_event *event, | |
ef5580d0 SR |
1251 | unsigned long flags, int pc) |
1252 | { | |
0d5c6e1c | 1253 | __trace_buffer_unlock_commit(buffer, event, flags, pc); |
07edf712 | 1254 | } |
94487d6d | 1255 | EXPORT_SYMBOL_GPL(trace_current_buffer_unlock_commit); |
07edf712 | 1256 | |
0d5c6e1c SR |
1257 | void trace_buffer_unlock_commit_regs(struct ring_buffer *buffer, |
1258 | struct ring_buffer_event *event, | |
1259 | unsigned long flags, int pc, | |
1260 | struct pt_regs *regs) | |
1fd8df2c | 1261 | { |
7ffbd48d | 1262 | __buffer_unlock_commit(buffer, event); |
1fd8df2c MH |
1263 | |
1264 | ftrace_trace_stack_regs(buffer, flags, 0, pc, regs); | |
1265 | ftrace_trace_userstack(buffer, flags, pc); | |
1266 | } | |
0d5c6e1c | 1267 | EXPORT_SYMBOL_GPL(trace_buffer_unlock_commit_regs); |
1fd8df2c | 1268 | |
e77405ad SR |
1269 | void trace_current_buffer_discard_commit(struct ring_buffer *buffer, |
1270 | struct ring_buffer_event *event) | |
77d9f465 | 1271 | { |
e77405ad | 1272 | ring_buffer_discard_commit(buffer, event); |
ef5580d0 | 1273 | } |
12acd473 | 1274 | EXPORT_SYMBOL_GPL(trace_current_buffer_discard_commit); |
ef5580d0 | 1275 | |
e309b41d | 1276 | void |
7be42151 | 1277 | trace_function(struct trace_array *tr, |
38697053 SR |
1278 | unsigned long ip, unsigned long parent_ip, unsigned long flags, |
1279 | int pc) | |
bc0c38d1 | 1280 | { |
e1112b4d | 1281 | struct ftrace_event_call *call = &event_function; |
e77405ad | 1282 | struct ring_buffer *buffer = tr->buffer; |
3928a8a2 | 1283 | struct ring_buffer_event *event; |
777e208d | 1284 | struct ftrace_entry *entry; |
bc0c38d1 | 1285 | |
d769041f | 1286 | /* If we are reading the ring buffer, don't trace */ |
dd17c8f7 | 1287 | if (unlikely(__this_cpu_read(ftrace_cpu_disabled))) |
d769041f SR |
1288 | return; |
1289 | ||
e77405ad | 1290 | event = trace_buffer_lock_reserve(buffer, TRACE_FN, sizeof(*entry), |
51a763dd | 1291 | flags, pc); |
3928a8a2 SR |
1292 | if (!event) |
1293 | return; | |
1294 | entry = ring_buffer_event_data(event); | |
777e208d SR |
1295 | entry->ip = ip; |
1296 | entry->parent_ip = parent_ip; | |
e1112b4d | 1297 | |
e77405ad | 1298 | if (!filter_check_discard(call, entry, buffer, event)) |
7ffbd48d | 1299 | __buffer_unlock_commit(buffer, event); |
bc0c38d1 SR |
1300 | } |
1301 | ||
e309b41d | 1302 | void |
2e0f5761 | 1303 | ftrace(struct trace_array *tr, struct trace_array_cpu *data, |
38697053 SR |
1304 | unsigned long ip, unsigned long parent_ip, unsigned long flags, |
1305 | int pc) | |
2e0f5761 IM |
1306 | { |
1307 | if (likely(!atomic_read(&data->disabled))) | |
7be42151 | 1308 | trace_function(tr, ip, parent_ip, flags, pc); |
2e0f5761 IM |
1309 | } |
1310 | ||
c0a0d0d3 | 1311 | #ifdef CONFIG_STACKTRACE |
4a9bd3f1 SR |
1312 | |
1313 | #define FTRACE_STACK_MAX_ENTRIES (PAGE_SIZE / sizeof(unsigned long)) | |
1314 | struct ftrace_stack { | |
1315 | unsigned long calls[FTRACE_STACK_MAX_ENTRIES]; | |
1316 | }; | |
1317 | ||
1318 | static DEFINE_PER_CPU(struct ftrace_stack, ftrace_stack); | |
1319 | static DEFINE_PER_CPU(int, ftrace_stack_reserve); | |
1320 | ||
e77405ad | 1321 | static void __ftrace_trace_stack(struct ring_buffer *buffer, |
53614991 | 1322 | unsigned long flags, |
1fd8df2c | 1323 | int skip, int pc, struct pt_regs *regs) |
86387f7e | 1324 | { |
e1112b4d | 1325 | struct ftrace_event_call *call = &event_kernel_stack; |
3928a8a2 | 1326 | struct ring_buffer_event *event; |
777e208d | 1327 | struct stack_entry *entry; |
86387f7e | 1328 | struct stack_trace trace; |
4a9bd3f1 SR |
1329 | int use_stack; |
1330 | int size = FTRACE_STACK_ENTRIES; | |
1331 | ||
1332 | trace.nr_entries = 0; | |
1333 | trace.skip = skip; | |
1334 | ||
1335 | /* | |
1336 | * Since events can happen in NMIs there's no safe way to | |
1337 | * use the per cpu ftrace_stacks. We reserve it and if an interrupt | |
1338 | * or NMI comes in, it will just have to use the default | |
1339 | * FTRACE_STACK_SIZE. | |
1340 | */ | |
1341 | preempt_disable_notrace(); | |
1342 | ||
1343 | use_stack = ++__get_cpu_var(ftrace_stack_reserve); | |
1344 | /* | |
1345 | * We don't need any atomic variables, just a barrier. | |
1346 | * If an interrupt comes in, we don't care, because it would | |
1347 | * have exited and put the counter back to what we want. | |
1348 | * We just need a barrier to keep gcc from moving things | |
1349 | * around. | |
1350 | */ | |
1351 | barrier(); | |
1352 | if (use_stack == 1) { | |
1353 | trace.entries = &__get_cpu_var(ftrace_stack).calls[0]; | |
1354 | trace.max_entries = FTRACE_STACK_MAX_ENTRIES; | |
1355 | ||
1356 | if (regs) | |
1357 | save_stack_trace_regs(regs, &trace); | |
1358 | else | |
1359 | save_stack_trace(&trace); | |
1360 | ||
1361 | if (trace.nr_entries > size) | |
1362 | size = trace.nr_entries; | |
1363 | } else | |
1364 | /* From now on, use_stack is a boolean */ | |
1365 | use_stack = 0; | |
1366 | ||
1367 | size *= sizeof(unsigned long); | |
86387f7e | 1368 | |
e77405ad | 1369 | event = trace_buffer_lock_reserve(buffer, TRACE_STACK, |
4a9bd3f1 | 1370 | sizeof(*entry) + size, flags, pc); |
3928a8a2 | 1371 | if (!event) |
4a9bd3f1 SR |
1372 | goto out; |
1373 | entry = ring_buffer_event_data(event); | |
86387f7e | 1374 | |
4a9bd3f1 SR |
1375 | memset(&entry->caller, 0, size); |
1376 | ||
1377 | if (use_stack) | |
1378 | memcpy(&entry->caller, trace.entries, | |
1379 | trace.nr_entries * sizeof(unsigned long)); | |
1380 | else { | |
1381 | trace.max_entries = FTRACE_STACK_ENTRIES; | |
1382 | trace.entries = entry->caller; | |
1383 | if (regs) | |
1384 | save_stack_trace_regs(regs, &trace); | |
1385 | else | |
1386 | save_stack_trace(&trace); | |
1387 | } | |
1388 | ||
1389 | entry->size = trace.nr_entries; | |
86387f7e | 1390 | |
e77405ad | 1391 | if (!filter_check_discard(call, entry, buffer, event)) |
7ffbd48d | 1392 | __buffer_unlock_commit(buffer, event); |
4a9bd3f1 SR |
1393 | |
1394 | out: | |
1395 | /* Again, don't let gcc optimize things here */ | |
1396 | barrier(); | |
1397 | __get_cpu_var(ftrace_stack_reserve)--; | |
1398 | preempt_enable_notrace(); | |
1399 | ||
f0a920d5 IM |
1400 | } |
1401 | ||
1fd8df2c MH |
1402 | void ftrace_trace_stack_regs(struct ring_buffer *buffer, unsigned long flags, |
1403 | int skip, int pc, struct pt_regs *regs) | |
1404 | { | |
1405 | if (!(trace_flags & TRACE_ITER_STACKTRACE)) | |
1406 | return; | |
1407 | ||
1408 | __ftrace_trace_stack(buffer, flags, skip, pc, regs); | |
1409 | } | |
1410 | ||
e77405ad SR |
1411 | void ftrace_trace_stack(struct ring_buffer *buffer, unsigned long flags, |
1412 | int skip, int pc) | |
53614991 SR |
1413 | { |
1414 | if (!(trace_flags & TRACE_ITER_STACKTRACE)) | |
1415 | return; | |
1416 | ||
1fd8df2c | 1417 | __ftrace_trace_stack(buffer, flags, skip, pc, NULL); |
53614991 SR |
1418 | } |
1419 | ||
c0a0d0d3 FW |
1420 | void __trace_stack(struct trace_array *tr, unsigned long flags, int skip, |
1421 | int pc) | |
38697053 | 1422 | { |
1fd8df2c | 1423 | __ftrace_trace_stack(tr->buffer, flags, skip, pc, NULL); |
38697053 SR |
1424 | } |
1425 | ||
03889384 SR |
1426 | /** |
1427 | * trace_dump_stack - record a stack back trace in the trace buffer | |
1428 | */ | |
1429 | void trace_dump_stack(void) | |
1430 | { | |
1431 | unsigned long flags; | |
1432 | ||
1433 | if (tracing_disabled || tracing_selftest_running) | |
e36c5458 | 1434 | return; |
03889384 SR |
1435 | |
1436 | local_save_flags(flags); | |
1437 | ||
1438 | /* skipping 3 traces, seems to get us at the caller of this function */ | |
1fd8df2c | 1439 | __ftrace_trace_stack(global_trace.buffer, flags, 3, preempt_count(), NULL); |
03889384 SR |
1440 | } |
1441 | ||
91e86e56 SR |
1442 | static DEFINE_PER_CPU(int, user_stack_count); |
1443 | ||
e77405ad SR |
1444 | void |
1445 | ftrace_trace_userstack(struct ring_buffer *buffer, unsigned long flags, int pc) | |
02b67518 | 1446 | { |
e1112b4d | 1447 | struct ftrace_event_call *call = &event_user_stack; |
8d7c6a96 | 1448 | struct ring_buffer_event *event; |
02b67518 TE |
1449 | struct userstack_entry *entry; |
1450 | struct stack_trace trace; | |
02b67518 TE |
1451 | |
1452 | if (!(trace_flags & TRACE_ITER_USERSTACKTRACE)) | |
1453 | return; | |
1454 | ||
b6345879 SR |
1455 | /* |
1456 | * NMIs can not handle page faults, even with fix ups. | |
1457 | * The save user stack can (and often does) fault. | |
1458 | */ | |
1459 | if (unlikely(in_nmi())) | |
1460 | return; | |
02b67518 | 1461 | |
91e86e56 SR |
1462 | /* |
1463 | * prevent recursion, since the user stack tracing may | |
1464 | * trigger other kernel events. | |
1465 | */ | |
1466 | preempt_disable(); | |
1467 | if (__this_cpu_read(user_stack_count)) | |
1468 | goto out; | |
1469 | ||
1470 | __this_cpu_inc(user_stack_count); | |
1471 | ||
e77405ad | 1472 | event = trace_buffer_lock_reserve(buffer, TRACE_USER_STACK, |
51a763dd | 1473 | sizeof(*entry), flags, pc); |
02b67518 | 1474 | if (!event) |
1dbd1951 | 1475 | goto out_drop_count; |
02b67518 | 1476 | entry = ring_buffer_event_data(event); |
02b67518 | 1477 | |
48659d31 | 1478 | entry->tgid = current->tgid; |
02b67518 TE |
1479 | memset(&entry->caller, 0, sizeof(entry->caller)); |
1480 | ||
1481 | trace.nr_entries = 0; | |
1482 | trace.max_entries = FTRACE_STACK_ENTRIES; | |
1483 | trace.skip = 0; | |
1484 | trace.entries = entry->caller; | |
1485 | ||
1486 | save_stack_trace_user(&trace); | |
e77405ad | 1487 | if (!filter_check_discard(call, entry, buffer, event)) |
7ffbd48d | 1488 | __buffer_unlock_commit(buffer, event); |
91e86e56 | 1489 | |
1dbd1951 | 1490 | out_drop_count: |
91e86e56 | 1491 | __this_cpu_dec(user_stack_count); |
91e86e56 SR |
1492 | out: |
1493 | preempt_enable(); | |
02b67518 TE |
1494 | } |
1495 | ||
4fd27358 HE |
1496 | #ifdef UNUSED |
1497 | static void __trace_userstack(struct trace_array *tr, unsigned long flags) | |
02b67518 | 1498 | { |
7be42151 | 1499 | ftrace_trace_userstack(tr, flags, preempt_count()); |
02b67518 | 1500 | } |
4fd27358 | 1501 | #endif /* UNUSED */ |
02b67518 | 1502 | |
c0a0d0d3 FW |
1503 | #endif /* CONFIG_STACKTRACE */ |
1504 | ||
07d777fe SR |
1505 | /* created for use with alloc_percpu */ |
1506 | struct trace_buffer_struct { | |
1507 | char buffer[TRACE_BUF_SIZE]; | |
1508 | }; | |
1509 | ||
1510 | static struct trace_buffer_struct *trace_percpu_buffer; | |
1511 | static struct trace_buffer_struct *trace_percpu_sirq_buffer; | |
1512 | static struct trace_buffer_struct *trace_percpu_irq_buffer; | |
1513 | static struct trace_buffer_struct *trace_percpu_nmi_buffer; | |
1514 | ||
1515 | /* | |
1516 | * The buffer used is dependent on the context. There is a per cpu | |
1517 | * buffer for normal context, softirq contex, hard irq context and | |
1518 | * for NMI context. Thise allows for lockless recording. | |
1519 | * | |
1520 | * Note, if the buffers failed to be allocated, then this returns NULL | |
1521 | */ | |
1522 | static char *get_trace_buf(void) | |
1523 | { | |
1524 | struct trace_buffer_struct *percpu_buffer; | |
07d777fe SR |
1525 | |
1526 | /* | |
1527 | * If we have allocated per cpu buffers, then we do not | |
1528 | * need to do any locking. | |
1529 | */ | |
1530 | if (in_nmi()) | |
1531 | percpu_buffer = trace_percpu_nmi_buffer; | |
1532 | else if (in_irq()) | |
1533 | percpu_buffer = trace_percpu_irq_buffer; | |
1534 | else if (in_softirq()) | |
1535 | percpu_buffer = trace_percpu_sirq_buffer; | |
1536 | else | |
1537 | percpu_buffer = trace_percpu_buffer; | |
1538 | ||
1539 | if (!percpu_buffer) | |
1540 | return NULL; | |
1541 | ||
d8a0349c | 1542 | return this_cpu_ptr(&percpu_buffer->buffer[0]); |
07d777fe SR |
1543 | } |
1544 | ||
1545 | static int alloc_percpu_trace_buffer(void) | |
1546 | { | |
1547 | struct trace_buffer_struct *buffers; | |
1548 | struct trace_buffer_struct *sirq_buffers; | |
1549 | struct trace_buffer_struct *irq_buffers; | |
1550 | struct trace_buffer_struct *nmi_buffers; | |
1551 | ||
1552 | buffers = alloc_percpu(struct trace_buffer_struct); | |
1553 | if (!buffers) | |
1554 | goto err_warn; | |
1555 | ||
1556 | sirq_buffers = alloc_percpu(struct trace_buffer_struct); | |
1557 | if (!sirq_buffers) | |
1558 | goto err_sirq; | |
1559 | ||
1560 | irq_buffers = alloc_percpu(struct trace_buffer_struct); | |
1561 | if (!irq_buffers) | |
1562 | goto err_irq; | |
1563 | ||
1564 | nmi_buffers = alloc_percpu(struct trace_buffer_struct); | |
1565 | if (!nmi_buffers) | |
1566 | goto err_nmi; | |
1567 | ||
1568 | trace_percpu_buffer = buffers; | |
1569 | trace_percpu_sirq_buffer = sirq_buffers; | |
1570 | trace_percpu_irq_buffer = irq_buffers; | |
1571 | trace_percpu_nmi_buffer = nmi_buffers; | |
1572 | ||
1573 | return 0; | |
1574 | ||
1575 | err_nmi: | |
1576 | free_percpu(irq_buffers); | |
1577 | err_irq: | |
1578 | free_percpu(sirq_buffers); | |
1579 | err_sirq: | |
1580 | free_percpu(buffers); | |
1581 | err_warn: | |
1582 | WARN(1, "Could not allocate percpu trace_printk buffer"); | |
1583 | return -ENOMEM; | |
1584 | } | |
1585 | ||
81698831 SR |
1586 | static int buffers_allocated; |
1587 | ||
07d777fe SR |
1588 | void trace_printk_init_buffers(void) |
1589 | { | |
07d777fe SR |
1590 | if (buffers_allocated) |
1591 | return; | |
1592 | ||
1593 | if (alloc_percpu_trace_buffer()) | |
1594 | return; | |
1595 | ||
1596 | pr_info("ftrace: Allocated trace_printk buffers\n"); | |
1597 | ||
b382ede6 SR |
1598 | /* Expand the buffers to set size */ |
1599 | tracing_update_buffers(); | |
1600 | ||
07d777fe | 1601 | buffers_allocated = 1; |
81698831 SR |
1602 | |
1603 | /* | |
1604 | * trace_printk_init_buffers() can be called by modules. | |
1605 | * If that happens, then we need to start cmdline recording | |
1606 | * directly here. If the global_trace.buffer is already | |
1607 | * allocated here, then this was called by module code. | |
1608 | */ | |
1609 | if (global_trace.buffer) | |
1610 | tracing_start_cmdline_record(); | |
1611 | } | |
1612 | ||
1613 | void trace_printk_start_comm(void) | |
1614 | { | |
1615 | /* Start tracing comms if trace printk is set */ | |
1616 | if (!buffers_allocated) | |
1617 | return; | |
1618 | tracing_start_cmdline_record(); | |
1619 | } | |
1620 | ||
1621 | static void trace_printk_start_stop_comm(int enabled) | |
1622 | { | |
1623 | if (!buffers_allocated) | |
1624 | return; | |
1625 | ||
1626 | if (enabled) | |
1627 | tracing_start_cmdline_record(); | |
1628 | else | |
1629 | tracing_stop_cmdline_record(); | |
07d777fe SR |
1630 | } |
1631 | ||
769b0441 | 1632 | /** |
48ead020 | 1633 | * trace_vbprintk - write binary msg to tracing buffer |
769b0441 FW |
1634 | * |
1635 | */ | |
40ce74f1 | 1636 | int trace_vbprintk(unsigned long ip, const char *fmt, va_list args) |
769b0441 | 1637 | { |
e1112b4d | 1638 | struct ftrace_event_call *call = &event_bprint; |
769b0441 | 1639 | struct ring_buffer_event *event; |
e77405ad | 1640 | struct ring_buffer *buffer; |
769b0441 | 1641 | struct trace_array *tr = &global_trace; |
48ead020 | 1642 | struct bprint_entry *entry; |
769b0441 | 1643 | unsigned long flags; |
07d777fe SR |
1644 | char *tbuffer; |
1645 | int len = 0, size, pc; | |
769b0441 FW |
1646 | |
1647 | if (unlikely(tracing_selftest_running || tracing_disabled)) | |
1648 | return 0; | |
1649 | ||
1650 | /* Don't pollute graph traces with trace_vprintk internals */ | |
1651 | pause_graph_tracing(); | |
1652 | ||
1653 | pc = preempt_count(); | |
5168ae50 | 1654 | preempt_disable_notrace(); |
769b0441 | 1655 | |
07d777fe SR |
1656 | tbuffer = get_trace_buf(); |
1657 | if (!tbuffer) { | |
1658 | len = 0; | |
769b0441 | 1659 | goto out; |
07d777fe | 1660 | } |
769b0441 | 1661 | |
07d777fe | 1662 | len = vbin_printf((u32 *)tbuffer, TRACE_BUF_SIZE/sizeof(int), fmt, args); |
769b0441 | 1663 | |
07d777fe SR |
1664 | if (len > TRACE_BUF_SIZE/sizeof(int) || len < 0) |
1665 | goto out; | |
769b0441 | 1666 | |
07d777fe | 1667 | local_save_flags(flags); |
769b0441 | 1668 | size = sizeof(*entry) + sizeof(u32) * len; |
e77405ad SR |
1669 | buffer = tr->buffer; |
1670 | event = trace_buffer_lock_reserve(buffer, TRACE_BPRINT, size, | |
1671 | flags, pc); | |
769b0441 | 1672 | if (!event) |
07d777fe | 1673 | goto out; |
769b0441 FW |
1674 | entry = ring_buffer_event_data(event); |
1675 | entry->ip = ip; | |
769b0441 FW |
1676 | entry->fmt = fmt; |
1677 | ||
07d777fe | 1678 | memcpy(entry->buf, tbuffer, sizeof(u32) * len); |
d931369b | 1679 | if (!filter_check_discard(call, entry, buffer, event)) { |
7ffbd48d | 1680 | __buffer_unlock_commit(buffer, event); |
d931369b SR |
1681 | ftrace_trace_stack(buffer, flags, 6, pc); |
1682 | } | |
769b0441 | 1683 | |
769b0441 | 1684 | out: |
5168ae50 | 1685 | preempt_enable_notrace(); |
769b0441 FW |
1686 | unpause_graph_tracing(); |
1687 | ||
1688 | return len; | |
1689 | } | |
48ead020 FW |
1690 | EXPORT_SYMBOL_GPL(trace_vbprintk); |
1691 | ||
659372d3 SR |
1692 | int trace_array_printk(struct trace_array *tr, |
1693 | unsigned long ip, const char *fmt, ...) | |
1694 | { | |
1695 | int ret; | |
1696 | va_list ap; | |
1697 | ||
1698 | if (!(trace_flags & TRACE_ITER_PRINTK)) | |
1699 | return 0; | |
1700 | ||
1701 | va_start(ap, fmt); | |
1702 | ret = trace_array_vprintk(tr, ip, fmt, ap); | |
1703 | va_end(ap); | |
1704 | return ret; | |
1705 | } | |
1706 | ||
1707 | int trace_array_vprintk(struct trace_array *tr, | |
1708 | unsigned long ip, const char *fmt, va_list args) | |
48ead020 | 1709 | { |
e1112b4d | 1710 | struct ftrace_event_call *call = &event_print; |
48ead020 | 1711 | struct ring_buffer_event *event; |
e77405ad | 1712 | struct ring_buffer *buffer; |
07d777fe | 1713 | int len = 0, size, pc; |
48ead020 | 1714 | struct print_entry *entry; |
07d777fe SR |
1715 | unsigned long flags; |
1716 | char *tbuffer; | |
48ead020 FW |
1717 | |
1718 | if (tracing_disabled || tracing_selftest_running) | |
1719 | return 0; | |
1720 | ||
07d777fe SR |
1721 | /* Don't pollute graph traces with trace_vprintk internals */ |
1722 | pause_graph_tracing(); | |
1723 | ||
48ead020 FW |
1724 | pc = preempt_count(); |
1725 | preempt_disable_notrace(); | |
48ead020 | 1726 | |
07d777fe SR |
1727 | |
1728 | tbuffer = get_trace_buf(); | |
1729 | if (!tbuffer) { | |
1730 | len = 0; | |
48ead020 | 1731 | goto out; |
07d777fe | 1732 | } |
48ead020 | 1733 | |
07d777fe SR |
1734 | len = vsnprintf(tbuffer, TRACE_BUF_SIZE, fmt, args); |
1735 | if (len > TRACE_BUF_SIZE) | |
1736 | goto out; | |
48ead020 | 1737 | |
07d777fe | 1738 | local_save_flags(flags); |
48ead020 | 1739 | size = sizeof(*entry) + len + 1; |
e77405ad SR |
1740 | buffer = tr->buffer; |
1741 | event = trace_buffer_lock_reserve(buffer, TRACE_PRINT, size, | |
07d777fe | 1742 | flags, pc); |
48ead020 | 1743 | if (!event) |
07d777fe | 1744 | goto out; |
48ead020 | 1745 | entry = ring_buffer_event_data(event); |
c13d2f7c | 1746 | entry->ip = ip; |
48ead020 | 1747 | |
07d777fe | 1748 | memcpy(&entry->buf, tbuffer, len); |
c13d2f7c | 1749 | entry->buf[len] = '\0'; |
d931369b | 1750 | if (!filter_check_discard(call, entry, buffer, event)) { |
7ffbd48d | 1751 | __buffer_unlock_commit(buffer, event); |
07d777fe | 1752 | ftrace_trace_stack(buffer, flags, 6, pc); |
d931369b | 1753 | } |
48ead020 FW |
1754 | out: |
1755 | preempt_enable_notrace(); | |
07d777fe | 1756 | unpause_graph_tracing(); |
48ead020 FW |
1757 | |
1758 | return len; | |
1759 | } | |
659372d3 SR |
1760 | |
1761 | int trace_vprintk(unsigned long ip, const char *fmt, va_list args) | |
1762 | { | |
a813a159 | 1763 | return trace_array_vprintk(&global_trace, ip, fmt, args); |
659372d3 | 1764 | } |
769b0441 FW |
1765 | EXPORT_SYMBOL_GPL(trace_vprintk); |
1766 | ||
e2ac8ef5 | 1767 | static void trace_iterator_increment(struct trace_iterator *iter) |
5a90f577 | 1768 | { |
6d158a81 SR |
1769 | struct ring_buffer_iter *buf_iter = trace_buffer_iter(iter, iter->cpu); |
1770 | ||
5a90f577 | 1771 | iter->idx++; |
6d158a81 SR |
1772 | if (buf_iter) |
1773 | ring_buffer_read(buf_iter, NULL); | |
5a90f577 SR |
1774 | } |
1775 | ||
e309b41d | 1776 | static struct trace_entry * |
bc21b478 SR |
1777 | peek_next_entry(struct trace_iterator *iter, int cpu, u64 *ts, |
1778 | unsigned long *lost_events) | |
dd0e545f | 1779 | { |
3928a8a2 | 1780 | struct ring_buffer_event *event; |
6d158a81 | 1781 | struct ring_buffer_iter *buf_iter = trace_buffer_iter(iter, cpu); |
dd0e545f | 1782 | |
d769041f SR |
1783 | if (buf_iter) |
1784 | event = ring_buffer_iter_peek(buf_iter, ts); | |
1785 | else | |
bc21b478 SR |
1786 | event = ring_buffer_peek(iter->tr->buffer, cpu, ts, |
1787 | lost_events); | |
d769041f | 1788 | |
4a9bd3f1 SR |
1789 | if (event) { |
1790 | iter->ent_size = ring_buffer_event_length(event); | |
1791 | return ring_buffer_event_data(event); | |
1792 | } | |
1793 | iter->ent_size = 0; | |
1794 | return NULL; | |
dd0e545f | 1795 | } |
d769041f | 1796 | |
dd0e545f | 1797 | static struct trace_entry * |
bc21b478 SR |
1798 | __find_next_entry(struct trace_iterator *iter, int *ent_cpu, |
1799 | unsigned long *missing_events, u64 *ent_ts) | |
bc0c38d1 | 1800 | { |
3928a8a2 | 1801 | struct ring_buffer *buffer = iter->tr->buffer; |
bc0c38d1 | 1802 | struct trace_entry *ent, *next = NULL; |
aa27497c | 1803 | unsigned long lost_events = 0, next_lost = 0; |
b04cc6b1 | 1804 | int cpu_file = iter->cpu_file; |
3928a8a2 | 1805 | u64 next_ts = 0, ts; |
bc0c38d1 | 1806 | int next_cpu = -1; |
12b5da34 | 1807 | int next_size = 0; |
bc0c38d1 SR |
1808 | int cpu; |
1809 | ||
b04cc6b1 FW |
1810 | /* |
1811 | * If we are in a per_cpu trace file, don't bother by iterating over | |
1812 | * all cpu and peek directly. | |
1813 | */ | |
1814 | if (cpu_file > TRACE_PIPE_ALL_CPU) { | |
1815 | if (ring_buffer_empty_cpu(buffer, cpu_file)) | |
1816 | return NULL; | |
bc21b478 | 1817 | ent = peek_next_entry(iter, cpu_file, ent_ts, missing_events); |
b04cc6b1 FW |
1818 | if (ent_cpu) |
1819 | *ent_cpu = cpu_file; | |
1820 | ||
1821 | return ent; | |
1822 | } | |
1823 | ||
ab46428c | 1824 | for_each_tracing_cpu(cpu) { |
dd0e545f | 1825 | |
3928a8a2 SR |
1826 | if (ring_buffer_empty_cpu(buffer, cpu)) |
1827 | continue; | |
dd0e545f | 1828 | |
bc21b478 | 1829 | ent = peek_next_entry(iter, cpu, &ts, &lost_events); |
dd0e545f | 1830 | |
cdd31cd2 IM |
1831 | /* |
1832 | * Pick the entry with the smallest timestamp: | |
1833 | */ | |
3928a8a2 | 1834 | if (ent && (!next || ts < next_ts)) { |
bc0c38d1 SR |
1835 | next = ent; |
1836 | next_cpu = cpu; | |
3928a8a2 | 1837 | next_ts = ts; |
bc21b478 | 1838 | next_lost = lost_events; |
12b5da34 | 1839 | next_size = iter->ent_size; |
bc0c38d1 SR |
1840 | } |
1841 | } | |
1842 | ||
12b5da34 SR |
1843 | iter->ent_size = next_size; |
1844 | ||
bc0c38d1 SR |
1845 | if (ent_cpu) |
1846 | *ent_cpu = next_cpu; | |
1847 | ||
3928a8a2 SR |
1848 | if (ent_ts) |
1849 | *ent_ts = next_ts; | |
1850 | ||
bc21b478 SR |
1851 | if (missing_events) |
1852 | *missing_events = next_lost; | |
1853 | ||
bc0c38d1 SR |
1854 | return next; |
1855 | } | |
1856 | ||
dd0e545f | 1857 | /* Find the next real entry, without updating the iterator itself */ |
c4a8e8be FW |
1858 | struct trace_entry *trace_find_next_entry(struct trace_iterator *iter, |
1859 | int *ent_cpu, u64 *ent_ts) | |
bc0c38d1 | 1860 | { |
bc21b478 | 1861 | return __find_next_entry(iter, ent_cpu, NULL, ent_ts); |
dd0e545f SR |
1862 | } |
1863 | ||
1864 | /* Find the next real entry, and increment the iterator to the next entry */ | |
955b61e5 | 1865 | void *trace_find_next_entry_inc(struct trace_iterator *iter) |
dd0e545f | 1866 | { |
bc21b478 SR |
1867 | iter->ent = __find_next_entry(iter, &iter->cpu, |
1868 | &iter->lost_events, &iter->ts); | |
dd0e545f | 1869 | |
3928a8a2 | 1870 | if (iter->ent) |
e2ac8ef5 | 1871 | trace_iterator_increment(iter); |
dd0e545f | 1872 | |
3928a8a2 | 1873 | return iter->ent ? iter : NULL; |
b3806b43 | 1874 | } |
bc0c38d1 | 1875 | |
e309b41d | 1876 | static void trace_consume(struct trace_iterator *iter) |
b3806b43 | 1877 | { |
bc21b478 SR |
1878 | ring_buffer_consume(iter->tr->buffer, iter->cpu, &iter->ts, |
1879 | &iter->lost_events); | |
bc0c38d1 SR |
1880 | } |
1881 | ||
e309b41d | 1882 | static void *s_next(struct seq_file *m, void *v, loff_t *pos) |
bc0c38d1 SR |
1883 | { |
1884 | struct trace_iterator *iter = m->private; | |
bc0c38d1 | 1885 | int i = (int)*pos; |
4e3c3333 | 1886 | void *ent; |
bc0c38d1 | 1887 | |
a63ce5b3 SR |
1888 | WARN_ON_ONCE(iter->leftover); |
1889 | ||
bc0c38d1 SR |
1890 | (*pos)++; |
1891 | ||
1892 | /* can't go backwards */ | |
1893 | if (iter->idx > i) | |
1894 | return NULL; | |
1895 | ||
1896 | if (iter->idx < 0) | |
955b61e5 | 1897 | ent = trace_find_next_entry_inc(iter); |
bc0c38d1 SR |
1898 | else |
1899 | ent = iter; | |
1900 | ||
1901 | while (ent && iter->idx < i) | |
955b61e5 | 1902 | ent = trace_find_next_entry_inc(iter); |
bc0c38d1 SR |
1903 | |
1904 | iter->pos = *pos; | |
1905 | ||
bc0c38d1 SR |
1906 | return ent; |
1907 | } | |
1908 | ||
955b61e5 | 1909 | void tracing_iter_reset(struct trace_iterator *iter, int cpu) |
2f26ebd5 SR |
1910 | { |
1911 | struct trace_array *tr = iter->tr; | |
1912 | struct ring_buffer_event *event; | |
1913 | struct ring_buffer_iter *buf_iter; | |
1914 | unsigned long entries = 0; | |
1915 | u64 ts; | |
1916 | ||
1917 | tr->data[cpu]->skipped_entries = 0; | |
1918 | ||
6d158a81 SR |
1919 | buf_iter = trace_buffer_iter(iter, cpu); |
1920 | if (!buf_iter) | |
2f26ebd5 SR |
1921 | return; |
1922 | ||
2f26ebd5 SR |
1923 | ring_buffer_iter_reset(buf_iter); |
1924 | ||
1925 | /* | |
1926 | * We could have the case with the max latency tracers | |
1927 | * that a reset never took place on a cpu. This is evident | |
1928 | * by the timestamp being before the start of the buffer. | |
1929 | */ | |
1930 | while ((event = ring_buffer_iter_peek(buf_iter, &ts))) { | |
1931 | if (ts >= iter->tr->time_start) | |
1932 | break; | |
1933 | entries++; | |
1934 | ring_buffer_read(buf_iter, NULL); | |
1935 | } | |
1936 | ||
1937 | tr->data[cpu]->skipped_entries = entries; | |
1938 | } | |
1939 | ||
d7350c3f | 1940 | /* |
d7350c3f FW |
1941 | * The current tracer is copied to avoid a global locking |
1942 | * all around. | |
1943 | */ | |
bc0c38d1 SR |
1944 | static void *s_start(struct seq_file *m, loff_t *pos) |
1945 | { | |
1946 | struct trace_iterator *iter = m->private; | |
d7350c3f | 1947 | static struct tracer *old_tracer; |
b04cc6b1 | 1948 | int cpu_file = iter->cpu_file; |
bc0c38d1 SR |
1949 | void *p = NULL; |
1950 | loff_t l = 0; | |
3928a8a2 | 1951 | int cpu; |
bc0c38d1 | 1952 | |
d7350c3f | 1953 | /* copy the tracer to avoid using a global lock all around */ |
bc0c38d1 | 1954 | mutex_lock(&trace_types_lock); |
d7350c3f FW |
1955 | if (unlikely(old_tracer != current_trace && current_trace)) { |
1956 | old_tracer = current_trace; | |
1957 | *iter->trace = *current_trace; | |
d15f57f2 | 1958 | } |
d7350c3f | 1959 | mutex_unlock(&trace_types_lock); |
bc0c38d1 SR |
1960 | |
1961 | atomic_inc(&trace_record_cmdline_disabled); | |
1962 | ||
bc0c38d1 SR |
1963 | if (*pos != iter->pos) { |
1964 | iter->ent = NULL; | |
1965 | iter->cpu = 0; | |
1966 | iter->idx = -1; | |
1967 | ||
b04cc6b1 FW |
1968 | if (cpu_file == TRACE_PIPE_ALL_CPU) { |
1969 | for_each_tracing_cpu(cpu) | |
2f26ebd5 | 1970 | tracing_iter_reset(iter, cpu); |
b04cc6b1 | 1971 | } else |
2f26ebd5 | 1972 | tracing_iter_reset(iter, cpu_file); |
bc0c38d1 | 1973 | |
ac91d854 | 1974 | iter->leftover = 0; |
bc0c38d1 SR |
1975 | for (p = iter; p && l < *pos; p = s_next(m, p, &l)) |
1976 | ; | |
1977 | ||
1978 | } else { | |
a63ce5b3 SR |
1979 | /* |
1980 | * If we overflowed the seq_file before, then we want | |
1981 | * to just reuse the trace_seq buffer again. | |
1982 | */ | |
1983 | if (iter->leftover) | |
1984 | p = iter; | |
1985 | else { | |
1986 | l = *pos - 1; | |
1987 | p = s_next(m, p, &l); | |
1988 | } | |
bc0c38d1 SR |
1989 | } |
1990 | ||
4f535968 | 1991 | trace_event_read_lock(); |
7e53bd42 | 1992 | trace_access_lock(cpu_file); |
bc0c38d1 SR |
1993 | return p; |
1994 | } | |
1995 | ||
1996 | static void s_stop(struct seq_file *m, void *p) | |
1997 | { | |
7e53bd42 LJ |
1998 | struct trace_iterator *iter = m->private; |
1999 | ||
bc0c38d1 | 2000 | atomic_dec(&trace_record_cmdline_disabled); |
7e53bd42 | 2001 | trace_access_unlock(iter->cpu_file); |
4f535968 | 2002 | trace_event_read_unlock(); |
bc0c38d1 SR |
2003 | } |
2004 | ||
39eaf7ef SR |
2005 | static void |
2006 | get_total_entries(struct trace_array *tr, unsigned long *total, unsigned long *entries) | |
2007 | { | |
2008 | unsigned long count; | |
2009 | int cpu; | |
2010 | ||
2011 | *total = 0; | |
2012 | *entries = 0; | |
2013 | ||
2014 | for_each_tracing_cpu(cpu) { | |
2015 | count = ring_buffer_entries_cpu(tr->buffer, cpu); | |
2016 | /* | |
2017 | * If this buffer has skipped entries, then we hold all | |
2018 | * entries for the trace and we need to ignore the | |
2019 | * ones before the time stamp. | |
2020 | */ | |
2021 | if (tr->data[cpu]->skipped_entries) { | |
2022 | count -= tr->data[cpu]->skipped_entries; | |
2023 | /* total is the same as the entries */ | |
2024 | *total += count; | |
2025 | } else | |
2026 | *total += count + | |
2027 | ring_buffer_overrun_cpu(tr->buffer, cpu); | |
2028 | *entries += count; | |
2029 | } | |
2030 | } | |
2031 | ||
e309b41d | 2032 | static void print_lat_help_header(struct seq_file *m) |
bc0c38d1 | 2033 | { |
a6168353 ME |
2034 | seq_puts(m, "# _------=> CPU# \n"); |
2035 | seq_puts(m, "# / _-----=> irqs-off \n"); | |
2036 | seq_puts(m, "# | / _----=> need-resched \n"); | |
2037 | seq_puts(m, "# || / _---=> hardirq/softirq \n"); | |
2038 | seq_puts(m, "# ||| / _--=> preempt-depth \n"); | |
e6e1e259 SR |
2039 | seq_puts(m, "# |||| / delay \n"); |
2040 | seq_puts(m, "# cmd pid ||||| time | caller \n"); | |
2041 | seq_puts(m, "# \\ / ||||| \\ | / \n"); | |
bc0c38d1 SR |
2042 | } |
2043 | ||
39eaf7ef | 2044 | static void print_event_info(struct trace_array *tr, struct seq_file *m) |
bc0c38d1 | 2045 | { |
39eaf7ef SR |
2046 | unsigned long total; |
2047 | unsigned long entries; | |
2048 | ||
2049 | get_total_entries(tr, &total, &entries); | |
2050 | seq_printf(m, "# entries-in-buffer/entries-written: %lu/%lu #P:%d\n", | |
2051 | entries, total, num_online_cpus()); | |
2052 | seq_puts(m, "#\n"); | |
2053 | } | |
2054 | ||
2055 | static void print_func_help_header(struct trace_array *tr, struct seq_file *m) | |
2056 | { | |
2057 | print_event_info(tr, m); | |
77271ce4 | 2058 | seq_puts(m, "# TASK-PID CPU# TIMESTAMP FUNCTION\n"); |
a6168353 | 2059 | seq_puts(m, "# | | | | |\n"); |
bc0c38d1 SR |
2060 | } |
2061 | ||
39eaf7ef | 2062 | static void print_func_help_header_irq(struct trace_array *tr, struct seq_file *m) |
77271ce4 | 2063 | { |
39eaf7ef | 2064 | print_event_info(tr, m); |
77271ce4 SR |
2065 | seq_puts(m, "# _-----=> irqs-off\n"); |
2066 | seq_puts(m, "# / _----=> need-resched\n"); | |
2067 | seq_puts(m, "# | / _---=> hardirq/softirq\n"); | |
2068 | seq_puts(m, "# || / _--=> preempt-depth\n"); | |
2069 | seq_puts(m, "# ||| / delay\n"); | |
2070 | seq_puts(m, "# TASK-PID CPU# |||| TIMESTAMP FUNCTION\n"); | |
2071 | seq_puts(m, "# | | | |||| | |\n"); | |
2072 | } | |
bc0c38d1 | 2073 | |
62b915f1 | 2074 | void |
bc0c38d1 SR |
2075 | print_trace_header(struct seq_file *m, struct trace_iterator *iter) |
2076 | { | |
2077 | unsigned long sym_flags = (trace_flags & TRACE_ITER_SYM_MASK); | |
2078 | struct trace_array *tr = iter->tr; | |
2079 | struct trace_array_cpu *data = tr->data[tr->cpu]; | |
2080 | struct tracer *type = current_trace; | |
39eaf7ef SR |
2081 | unsigned long entries; |
2082 | unsigned long total; | |
bc0c38d1 SR |
2083 | const char *name = "preemption"; |
2084 | ||
2085 | if (type) | |
2086 | name = type->name; | |
2087 | ||
39eaf7ef | 2088 | get_total_entries(tr, &total, &entries); |
bc0c38d1 | 2089 | |
888b55dc | 2090 | seq_printf(m, "# %s latency trace v1.1.5 on %s\n", |
bc0c38d1 | 2091 | name, UTS_RELEASE); |
888b55dc | 2092 | seq_puts(m, "# -----------------------------------" |
bc0c38d1 | 2093 | "---------------------------------\n"); |
888b55dc | 2094 | seq_printf(m, "# latency: %lu us, #%lu/%lu, CPU#%d |" |
bc0c38d1 | 2095 | " (M:%s VP:%d, KP:%d, SP:%d HP:%d", |
57f50be1 | 2096 | nsecs_to_usecs(data->saved_latency), |
bc0c38d1 | 2097 | entries, |
4c11d7ae | 2098 | total, |
bc0c38d1 SR |
2099 | tr->cpu, |
2100 | #if defined(CONFIG_PREEMPT_NONE) | |
2101 | "server", | |
2102 | #elif defined(CONFIG_PREEMPT_VOLUNTARY) | |
2103 | "desktop", | |
b5c21b45 | 2104 | #elif defined(CONFIG_PREEMPT) |
bc0c38d1 SR |
2105 | "preempt", |
2106 | #else | |
2107 | "unknown", | |
2108 | #endif | |
2109 | /* These are reserved for later use */ | |
2110 | 0, 0, 0, 0); | |
2111 | #ifdef CONFIG_SMP | |
2112 | seq_printf(m, " #P:%d)\n", num_online_cpus()); | |
2113 | #else | |
2114 | seq_puts(m, ")\n"); | |
2115 | #endif | |
888b55dc KM |
2116 | seq_puts(m, "# -----------------\n"); |
2117 | seq_printf(m, "# | task: %.16s-%d " | |
bc0c38d1 | 2118 | "(uid:%d nice:%ld policy:%ld rt_prio:%ld)\n", |
d20b92ab EB |
2119 | data->comm, data->pid, |
2120 | from_kuid_munged(seq_user_ns(m), data->uid), data->nice, | |
bc0c38d1 | 2121 | data->policy, data->rt_priority); |
888b55dc | 2122 | seq_puts(m, "# -----------------\n"); |
bc0c38d1 SR |
2123 | |
2124 | if (data->critical_start) { | |
888b55dc | 2125 | seq_puts(m, "# => started at: "); |
214023c3 SR |
2126 | seq_print_ip_sym(&iter->seq, data->critical_start, sym_flags); |
2127 | trace_print_seq(m, &iter->seq); | |
888b55dc | 2128 | seq_puts(m, "\n# => ended at: "); |
214023c3 SR |
2129 | seq_print_ip_sym(&iter->seq, data->critical_end, sym_flags); |
2130 | trace_print_seq(m, &iter->seq); | |
8248ac05 | 2131 | seq_puts(m, "\n#\n"); |
bc0c38d1 SR |
2132 | } |
2133 | ||
888b55dc | 2134 | seq_puts(m, "#\n"); |
bc0c38d1 SR |
2135 | } |
2136 | ||
a309720c SR |
2137 | static void test_cpu_buff_start(struct trace_iterator *iter) |
2138 | { | |
2139 | struct trace_seq *s = &iter->seq; | |
2140 | ||
12ef7d44 SR |
2141 | if (!(trace_flags & TRACE_ITER_ANNOTATE)) |
2142 | return; | |
2143 | ||
2144 | if (!(iter->iter_flags & TRACE_FILE_ANNOTATE)) | |
2145 | return; | |
2146 | ||
4462344e | 2147 | if (cpumask_test_cpu(iter->cpu, iter->started)) |
a309720c SR |
2148 | return; |
2149 | ||
2f26ebd5 SR |
2150 | if (iter->tr->data[iter->cpu]->skipped_entries) |
2151 | return; | |
2152 | ||
4462344e | 2153 | cpumask_set_cpu(iter->cpu, iter->started); |
b0dfa978 FW |
2154 | |
2155 | /* Don't print started cpu buffer for the first entry of the trace */ | |
2156 | if (iter->idx > 1) | |
2157 | trace_seq_printf(s, "##### CPU %u buffer started ####\n", | |
2158 | iter->cpu); | |
a309720c SR |
2159 | } |
2160 | ||
2c4f035f | 2161 | static enum print_line_t print_trace_fmt(struct trace_iterator *iter) |
bc0c38d1 | 2162 | { |
214023c3 | 2163 | struct trace_seq *s = &iter->seq; |
bc0c38d1 | 2164 | unsigned long sym_flags = (trace_flags & TRACE_ITER_SYM_MASK); |
4e3c3333 | 2165 | struct trace_entry *entry; |
f633cef0 | 2166 | struct trace_event *event; |
bc0c38d1 | 2167 | |
4e3c3333 | 2168 | entry = iter->ent; |
dd0e545f | 2169 | |
a309720c SR |
2170 | test_cpu_buff_start(iter); |
2171 | ||
c4a8e8be | 2172 | event = ftrace_find_event(entry->type); |
bc0c38d1 | 2173 | |
c4a8e8be | 2174 | if (trace_flags & TRACE_ITER_CONTEXT_INFO) { |
27d48be8 SR |
2175 | if (iter->iter_flags & TRACE_FILE_LAT_FMT) { |
2176 | if (!trace_print_lat_context(iter)) | |
2177 | goto partial; | |
2178 | } else { | |
2179 | if (!trace_print_context(iter)) | |
2180 | goto partial; | |
2181 | } | |
c4a8e8be | 2182 | } |
bc0c38d1 | 2183 | |
268ccda0 | 2184 | if (event) |
a9a57763 | 2185 | return event->funcs->trace(iter, sym_flags, event); |
d9793bd8 ACM |
2186 | |
2187 | if (!trace_seq_printf(s, "Unknown type %d\n", entry->type)) | |
2188 | goto partial; | |
02b67518 | 2189 | |
2c4f035f | 2190 | return TRACE_TYPE_HANDLED; |
d9793bd8 ACM |
2191 | partial: |
2192 | return TRACE_TYPE_PARTIAL_LINE; | |
bc0c38d1 SR |
2193 | } |
2194 | ||
2c4f035f | 2195 | static enum print_line_t print_raw_fmt(struct trace_iterator *iter) |
f9896bf3 IM |
2196 | { |
2197 | struct trace_seq *s = &iter->seq; | |
2198 | struct trace_entry *entry; | |
f633cef0 | 2199 | struct trace_event *event; |
f9896bf3 IM |
2200 | |
2201 | entry = iter->ent; | |
dd0e545f | 2202 | |
c4a8e8be | 2203 | if (trace_flags & TRACE_ITER_CONTEXT_INFO) { |
d9793bd8 ACM |
2204 | if (!trace_seq_printf(s, "%d %d %llu ", |
2205 | entry->pid, iter->cpu, iter->ts)) | |
2206 | goto partial; | |
c4a8e8be | 2207 | } |
f9896bf3 | 2208 | |
f633cef0 | 2209 | event = ftrace_find_event(entry->type); |
268ccda0 | 2210 | if (event) |
a9a57763 | 2211 | return event->funcs->raw(iter, 0, event); |
d9793bd8 ACM |
2212 | |
2213 | if (!trace_seq_printf(s, "%d ?\n", entry->type)) | |
2214 | goto partial; | |
777e208d | 2215 | |
2c4f035f | 2216 | return TRACE_TYPE_HANDLED; |
d9793bd8 ACM |
2217 | partial: |
2218 | return TRACE_TYPE_PARTIAL_LINE; | |
f9896bf3 IM |
2219 | } |
2220 | ||
2c4f035f | 2221 | static enum print_line_t print_hex_fmt(struct trace_iterator *iter) |
5e3ca0ec IM |
2222 | { |
2223 | struct trace_seq *s = &iter->seq; | |
2224 | unsigned char newline = '\n'; | |
2225 | struct trace_entry *entry; | |
f633cef0 | 2226 | struct trace_event *event; |
5e3ca0ec IM |
2227 | |
2228 | entry = iter->ent; | |
dd0e545f | 2229 | |
c4a8e8be FW |
2230 | if (trace_flags & TRACE_ITER_CONTEXT_INFO) { |
2231 | SEQ_PUT_HEX_FIELD_RET(s, entry->pid); | |
2232 | SEQ_PUT_HEX_FIELD_RET(s, iter->cpu); | |
2233 | SEQ_PUT_HEX_FIELD_RET(s, iter->ts); | |
2234 | } | |
5e3ca0ec | 2235 | |
f633cef0 | 2236 | event = ftrace_find_event(entry->type); |
268ccda0 | 2237 | if (event) { |
a9a57763 | 2238 | enum print_line_t ret = event->funcs->hex(iter, 0, event); |
d9793bd8 ACM |
2239 | if (ret != TRACE_TYPE_HANDLED) |
2240 | return ret; | |
2241 | } | |
7104f300 | 2242 | |
5e3ca0ec IM |
2243 | SEQ_PUT_FIELD_RET(s, newline); |
2244 | ||
2c4f035f | 2245 | return TRACE_TYPE_HANDLED; |
5e3ca0ec IM |
2246 | } |
2247 | ||
2c4f035f | 2248 | static enum print_line_t print_bin_fmt(struct trace_iterator *iter) |
cb0f12aa IM |
2249 | { |
2250 | struct trace_seq *s = &iter->seq; | |
2251 | struct trace_entry *entry; | |
f633cef0 | 2252 | struct trace_event *event; |
cb0f12aa IM |
2253 | |
2254 | entry = iter->ent; | |
dd0e545f | 2255 | |
c4a8e8be FW |
2256 | if (trace_flags & TRACE_ITER_CONTEXT_INFO) { |
2257 | SEQ_PUT_FIELD_RET(s, entry->pid); | |
1830b52d | 2258 | SEQ_PUT_FIELD_RET(s, iter->cpu); |
c4a8e8be FW |
2259 | SEQ_PUT_FIELD_RET(s, iter->ts); |
2260 | } | |
cb0f12aa | 2261 | |
f633cef0 | 2262 | event = ftrace_find_event(entry->type); |
a9a57763 SR |
2263 | return event ? event->funcs->binary(iter, 0, event) : |
2264 | TRACE_TYPE_HANDLED; | |
cb0f12aa IM |
2265 | } |
2266 | ||
62b915f1 | 2267 | int trace_empty(struct trace_iterator *iter) |
bc0c38d1 | 2268 | { |
6d158a81 | 2269 | struct ring_buffer_iter *buf_iter; |
bc0c38d1 SR |
2270 | int cpu; |
2271 | ||
9aba60fe SR |
2272 | /* If we are looking at one CPU buffer, only check that one */ |
2273 | if (iter->cpu_file != TRACE_PIPE_ALL_CPU) { | |
2274 | cpu = iter->cpu_file; | |
6d158a81 SR |
2275 | buf_iter = trace_buffer_iter(iter, cpu); |
2276 | if (buf_iter) { | |
2277 | if (!ring_buffer_iter_empty(buf_iter)) | |
9aba60fe SR |
2278 | return 0; |
2279 | } else { | |
2280 | if (!ring_buffer_empty_cpu(iter->tr->buffer, cpu)) | |
2281 | return 0; | |
2282 | } | |
2283 | return 1; | |
2284 | } | |
2285 | ||
ab46428c | 2286 | for_each_tracing_cpu(cpu) { |
6d158a81 SR |
2287 | buf_iter = trace_buffer_iter(iter, cpu); |
2288 | if (buf_iter) { | |
2289 | if (!ring_buffer_iter_empty(buf_iter)) | |
d769041f SR |
2290 | return 0; |
2291 | } else { | |
2292 | if (!ring_buffer_empty_cpu(iter->tr->buffer, cpu)) | |
2293 | return 0; | |
2294 | } | |
bc0c38d1 | 2295 | } |
d769041f | 2296 | |
797d3712 | 2297 | return 1; |
bc0c38d1 SR |
2298 | } |
2299 | ||
4f535968 | 2300 | /* Called with trace_event_read_lock() held. */ |
955b61e5 | 2301 | enum print_line_t print_trace_line(struct trace_iterator *iter) |
f9896bf3 | 2302 | { |
2c4f035f FW |
2303 | enum print_line_t ret; |
2304 | ||
ee5e51f5 JO |
2305 | if (iter->lost_events && |
2306 | !trace_seq_printf(&iter->seq, "CPU:%d [LOST %lu EVENTS]\n", | |
2307 | iter->cpu, iter->lost_events)) | |
2308 | return TRACE_TYPE_PARTIAL_LINE; | |
bc21b478 | 2309 | |
2c4f035f FW |
2310 | if (iter->trace && iter->trace->print_line) { |
2311 | ret = iter->trace->print_line(iter); | |
2312 | if (ret != TRACE_TYPE_UNHANDLED) | |
2313 | return ret; | |
2314 | } | |
72829bc3 | 2315 | |
48ead020 FW |
2316 | if (iter->ent->type == TRACE_BPRINT && |
2317 | trace_flags & TRACE_ITER_PRINTK && | |
2318 | trace_flags & TRACE_ITER_PRINTK_MSGONLY) | |
5ef841f6 | 2319 | return trace_print_bprintk_msg_only(iter); |
48ead020 | 2320 | |
66896a85 FW |
2321 | if (iter->ent->type == TRACE_PRINT && |
2322 | trace_flags & TRACE_ITER_PRINTK && | |
2323 | trace_flags & TRACE_ITER_PRINTK_MSGONLY) | |
5ef841f6 | 2324 | return trace_print_printk_msg_only(iter); |
66896a85 | 2325 | |
cb0f12aa IM |
2326 | if (trace_flags & TRACE_ITER_BIN) |
2327 | return print_bin_fmt(iter); | |
2328 | ||
5e3ca0ec IM |
2329 | if (trace_flags & TRACE_ITER_HEX) |
2330 | return print_hex_fmt(iter); | |
2331 | ||
f9896bf3 IM |
2332 | if (trace_flags & TRACE_ITER_RAW) |
2333 | return print_raw_fmt(iter); | |
2334 | ||
f9896bf3 IM |
2335 | return print_trace_fmt(iter); |
2336 | } | |
2337 | ||
7e9a49ef JO |
2338 | void trace_latency_header(struct seq_file *m) |
2339 | { | |
2340 | struct trace_iterator *iter = m->private; | |
2341 | ||
2342 | /* print nothing if the buffers are empty */ | |
2343 | if (trace_empty(iter)) | |
2344 | return; | |
2345 | ||
2346 | if (iter->iter_flags & TRACE_FILE_LAT_FMT) | |
2347 | print_trace_header(m, iter); | |
2348 | ||
2349 | if (!(trace_flags & TRACE_ITER_VERBOSE)) | |
2350 | print_lat_help_header(m); | |
2351 | } | |
2352 | ||
62b915f1 JO |
2353 | void trace_default_header(struct seq_file *m) |
2354 | { | |
2355 | struct trace_iterator *iter = m->private; | |
2356 | ||
f56e7f8e JO |
2357 | if (!(trace_flags & TRACE_ITER_CONTEXT_INFO)) |
2358 | return; | |
2359 | ||
62b915f1 JO |
2360 | if (iter->iter_flags & TRACE_FILE_LAT_FMT) { |
2361 | /* print nothing if the buffers are empty */ | |
2362 | if (trace_empty(iter)) | |
2363 | return; | |
2364 | print_trace_header(m, iter); | |
2365 | if (!(trace_flags & TRACE_ITER_VERBOSE)) | |
2366 | print_lat_help_header(m); | |
2367 | } else { | |
77271ce4 SR |
2368 | if (!(trace_flags & TRACE_ITER_VERBOSE)) { |
2369 | if (trace_flags & TRACE_ITER_IRQ_INFO) | |
39eaf7ef | 2370 | print_func_help_header_irq(iter->tr, m); |
77271ce4 | 2371 | else |
39eaf7ef | 2372 | print_func_help_header(iter->tr, m); |
77271ce4 | 2373 | } |
62b915f1 JO |
2374 | } |
2375 | } | |
2376 | ||
e0a413f6 SR |
2377 | static void test_ftrace_alive(struct seq_file *m) |
2378 | { | |
2379 | if (!ftrace_is_dead()) | |
2380 | return; | |
2381 | seq_printf(m, "# WARNING: FUNCTION TRACING IS CORRUPTED\n"); | |
2382 | seq_printf(m, "# MAY BE MISSING FUNCTION EVENTS\n"); | |
2383 | } | |
2384 | ||
bc0c38d1 SR |
2385 | static int s_show(struct seq_file *m, void *v) |
2386 | { | |
2387 | struct trace_iterator *iter = v; | |
a63ce5b3 | 2388 | int ret; |
bc0c38d1 SR |
2389 | |
2390 | if (iter->ent == NULL) { | |
2391 | if (iter->tr) { | |
2392 | seq_printf(m, "# tracer: %s\n", iter->trace->name); | |
2393 | seq_puts(m, "#\n"); | |
e0a413f6 | 2394 | test_ftrace_alive(m); |
bc0c38d1 | 2395 | } |
8bba1bf5 MM |
2396 | if (iter->trace && iter->trace->print_header) |
2397 | iter->trace->print_header(m); | |
62b915f1 JO |
2398 | else |
2399 | trace_default_header(m); | |
2400 | ||
a63ce5b3 SR |
2401 | } else if (iter->leftover) { |
2402 | /* | |
2403 | * If we filled the seq_file buffer earlier, we | |
2404 | * want to just show it now. | |
2405 | */ | |
2406 | ret = trace_print_seq(m, &iter->seq); | |
2407 | ||
2408 | /* ret should this time be zero, but you never know */ | |
2409 | iter->leftover = ret; | |
2410 | ||
bc0c38d1 | 2411 | } else { |
f9896bf3 | 2412 | print_trace_line(iter); |
a63ce5b3 SR |
2413 | ret = trace_print_seq(m, &iter->seq); |
2414 | /* | |
2415 | * If we overflow the seq_file buffer, then it will | |
2416 | * ask us for this data again at start up. | |
2417 | * Use that instead. | |
2418 | * ret is 0 if seq_file write succeeded. | |
2419 | * -1 otherwise. | |
2420 | */ | |
2421 | iter->leftover = ret; | |
bc0c38d1 SR |
2422 | } |
2423 | ||
2424 | return 0; | |
2425 | } | |
2426 | ||
88e9d34c | 2427 | static const struct seq_operations tracer_seq_ops = { |
4bf39a94 IM |
2428 | .start = s_start, |
2429 | .next = s_next, | |
2430 | .stop = s_stop, | |
2431 | .show = s_show, | |
bc0c38d1 SR |
2432 | }; |
2433 | ||
e309b41d | 2434 | static struct trace_iterator * |
85a2f9b4 | 2435 | __tracing_open(struct inode *inode, struct file *file) |
bc0c38d1 | 2436 | { |
b04cc6b1 | 2437 | long cpu_file = (long) inode->i_private; |
bc0c38d1 | 2438 | struct trace_iterator *iter; |
50e18b94 | 2439 | int cpu; |
bc0c38d1 | 2440 | |
85a2f9b4 SR |
2441 | if (tracing_disabled) |
2442 | return ERR_PTR(-ENODEV); | |
60a11774 | 2443 | |
50e18b94 | 2444 | iter = __seq_open_private(file, &tracer_seq_ops, sizeof(*iter)); |
85a2f9b4 SR |
2445 | if (!iter) |
2446 | return ERR_PTR(-ENOMEM); | |
bc0c38d1 | 2447 | |
6d158a81 SR |
2448 | iter->buffer_iter = kzalloc(sizeof(*iter->buffer_iter) * num_possible_cpus(), |
2449 | GFP_KERNEL); | |
93574fcc DC |
2450 | if (!iter->buffer_iter) |
2451 | goto release; | |
2452 | ||
d7350c3f FW |
2453 | /* |
2454 | * We make a copy of the current tracer to avoid concurrent | |
2455 | * changes on it while we are reading. | |
2456 | */ | |
bc0c38d1 | 2457 | mutex_lock(&trace_types_lock); |
d7350c3f | 2458 | iter->trace = kzalloc(sizeof(*iter->trace), GFP_KERNEL); |
85a2f9b4 | 2459 | if (!iter->trace) |
d7350c3f | 2460 | goto fail; |
85a2f9b4 | 2461 | |
d7350c3f FW |
2462 | if (current_trace) |
2463 | *iter->trace = *current_trace; | |
2464 | ||
79f55997 | 2465 | if (!zalloc_cpumask_var(&iter->started, GFP_KERNEL)) |
b0dfa978 FW |
2466 | goto fail; |
2467 | ||
bc0c38d1 SR |
2468 | if (current_trace && current_trace->print_max) |
2469 | iter->tr = &max_tr; | |
2470 | else | |
b04cc6b1 | 2471 | iter->tr = &global_trace; |
bc0c38d1 | 2472 | iter->pos = -1; |
d7350c3f | 2473 | mutex_init(&iter->mutex); |
b04cc6b1 | 2474 | iter->cpu_file = cpu_file; |
bc0c38d1 | 2475 | |
8bba1bf5 MM |
2476 | /* Notify the tracer early; before we stop tracing. */ |
2477 | if (iter->trace && iter->trace->open) | |
a93751ca | 2478 | iter->trace->open(iter); |
8bba1bf5 | 2479 | |
12ef7d44 SR |
2480 | /* Annotate start of buffers if we had overruns */ |
2481 | if (ring_buffer_overruns(iter->tr->buffer)) | |
2482 | iter->iter_flags |= TRACE_FILE_ANNOTATE; | |
2483 | ||
8be0709f DS |
2484 | /* Output in nanoseconds only if we are using a clock in nanoseconds. */ |
2485 | if (trace_clocks[trace_clock_id].in_ns) | |
2486 | iter->iter_flags |= TRACE_FILE_TIME_IN_NS; | |
2487 | ||
2f26ebd5 SR |
2488 | /* stop the trace while dumping */ |
2489 | tracing_stop(); | |
2490 | ||
b04cc6b1 FW |
2491 | if (iter->cpu_file == TRACE_PIPE_ALL_CPU) { |
2492 | for_each_tracing_cpu(cpu) { | |
b04cc6b1 | 2493 | iter->buffer_iter[cpu] = |
72c9ddfd DM |
2494 | ring_buffer_read_prepare(iter->tr->buffer, cpu); |
2495 | } | |
2496 | ring_buffer_read_prepare_sync(); | |
2497 | for_each_tracing_cpu(cpu) { | |
2498 | ring_buffer_read_start(iter->buffer_iter[cpu]); | |
2f26ebd5 | 2499 | tracing_iter_reset(iter, cpu); |
b04cc6b1 FW |
2500 | } |
2501 | } else { | |
2502 | cpu = iter->cpu_file; | |
3928a8a2 | 2503 | iter->buffer_iter[cpu] = |
72c9ddfd DM |
2504 | ring_buffer_read_prepare(iter->tr->buffer, cpu); |
2505 | ring_buffer_read_prepare_sync(); | |
2506 | ring_buffer_read_start(iter->buffer_iter[cpu]); | |
2f26ebd5 | 2507 | tracing_iter_reset(iter, cpu); |
3928a8a2 SR |
2508 | } |
2509 | ||
bc0c38d1 SR |
2510 | mutex_unlock(&trace_types_lock); |
2511 | ||
bc0c38d1 | 2512 | return iter; |
3928a8a2 | 2513 | |
d7350c3f | 2514 | fail: |
3928a8a2 | 2515 | mutex_unlock(&trace_types_lock); |
d7350c3f | 2516 | kfree(iter->trace); |
6d158a81 | 2517 | kfree(iter->buffer_iter); |
93574fcc | 2518 | release: |
50e18b94 JO |
2519 | seq_release_private(inode, file); |
2520 | return ERR_PTR(-ENOMEM); | |
bc0c38d1 SR |
2521 | } |
2522 | ||
2523 | int tracing_open_generic(struct inode *inode, struct file *filp) | |
2524 | { | |
60a11774 SR |
2525 | if (tracing_disabled) |
2526 | return -ENODEV; | |
2527 | ||
bc0c38d1 SR |
2528 | filp->private_data = inode->i_private; |
2529 | return 0; | |
2530 | } | |
2531 | ||
4fd27358 | 2532 | static int tracing_release(struct inode *inode, struct file *file) |
bc0c38d1 | 2533 | { |
907f2784 | 2534 | struct seq_file *m = file->private_data; |
4acd4d00 | 2535 | struct trace_iterator *iter; |
3928a8a2 | 2536 | int cpu; |
bc0c38d1 | 2537 | |
4acd4d00 SR |
2538 | if (!(file->f_mode & FMODE_READ)) |
2539 | return 0; | |
2540 | ||
2541 | iter = m->private; | |
2542 | ||
bc0c38d1 | 2543 | mutex_lock(&trace_types_lock); |
3928a8a2 SR |
2544 | for_each_tracing_cpu(cpu) { |
2545 | if (iter->buffer_iter[cpu]) | |
2546 | ring_buffer_read_finish(iter->buffer_iter[cpu]); | |
2547 | } | |
2548 | ||
bc0c38d1 SR |
2549 | if (iter->trace && iter->trace->close) |
2550 | iter->trace->close(iter); | |
2551 | ||
2552 | /* reenable tracing if it was previously enabled */ | |
9036990d | 2553 | tracing_start(); |
bc0c38d1 SR |
2554 | mutex_unlock(&trace_types_lock); |
2555 | ||
d7350c3f | 2556 | mutex_destroy(&iter->mutex); |
b0dfa978 | 2557 | free_cpumask_var(iter->started); |
d7350c3f | 2558 | kfree(iter->trace); |
6d158a81 | 2559 | kfree(iter->buffer_iter); |
50e18b94 | 2560 | seq_release_private(inode, file); |
bc0c38d1 SR |
2561 | return 0; |
2562 | } | |
2563 | ||
2564 | static int tracing_open(struct inode *inode, struct file *file) | |
2565 | { | |
85a2f9b4 SR |
2566 | struct trace_iterator *iter; |
2567 | int ret = 0; | |
bc0c38d1 | 2568 | |
4acd4d00 SR |
2569 | /* If this file was open for write, then erase contents */ |
2570 | if ((file->f_mode & FMODE_WRITE) && | |
8650ae32 | 2571 | (file->f_flags & O_TRUNC)) { |
4acd4d00 | 2572 | long cpu = (long) inode->i_private; |
bc0c38d1 | 2573 | |
4acd4d00 SR |
2574 | if (cpu == TRACE_PIPE_ALL_CPU) |
2575 | tracing_reset_online_cpus(&global_trace); | |
2576 | else | |
2577 | tracing_reset(&global_trace, cpu); | |
2578 | } | |
bc0c38d1 | 2579 | |
4acd4d00 SR |
2580 | if (file->f_mode & FMODE_READ) { |
2581 | iter = __tracing_open(inode, file); | |
2582 | if (IS_ERR(iter)) | |
2583 | ret = PTR_ERR(iter); | |
2584 | else if (trace_flags & TRACE_ITER_LATENCY_FMT) | |
2585 | iter->iter_flags |= TRACE_FILE_LAT_FMT; | |
2586 | } | |
bc0c38d1 SR |
2587 | return ret; |
2588 | } | |
2589 | ||
e309b41d | 2590 | static void * |
bc0c38d1 SR |
2591 | t_next(struct seq_file *m, void *v, loff_t *pos) |
2592 | { | |
f129e965 | 2593 | struct tracer *t = v; |
bc0c38d1 SR |
2594 | |
2595 | (*pos)++; | |
2596 | ||
2597 | if (t) | |
2598 | t = t->next; | |
2599 | ||
bc0c38d1 SR |
2600 | return t; |
2601 | } | |
2602 | ||
2603 | static void *t_start(struct seq_file *m, loff_t *pos) | |
2604 | { | |
f129e965 | 2605 | struct tracer *t; |
bc0c38d1 SR |
2606 | loff_t l = 0; |
2607 | ||
2608 | mutex_lock(&trace_types_lock); | |
f129e965 | 2609 | for (t = trace_types; t && l < *pos; t = t_next(m, t, &l)) |
bc0c38d1 SR |
2610 | ; |
2611 | ||
2612 | return t; | |
2613 | } | |
2614 | ||
2615 | static void t_stop(struct seq_file *m, void *p) | |
2616 | { | |
2617 | mutex_unlock(&trace_types_lock); | |
2618 | } | |
2619 | ||
2620 | static int t_show(struct seq_file *m, void *v) | |
2621 | { | |
2622 | struct tracer *t = v; | |
2623 | ||
2624 | if (!t) | |
2625 | return 0; | |
2626 | ||
2627 | seq_printf(m, "%s", t->name); | |
2628 | if (t->next) | |
2629 | seq_putc(m, ' '); | |
2630 | else | |
2631 | seq_putc(m, '\n'); | |
2632 | ||
2633 | return 0; | |
2634 | } | |
2635 | ||
88e9d34c | 2636 | static const struct seq_operations show_traces_seq_ops = { |
4bf39a94 IM |
2637 | .start = t_start, |
2638 | .next = t_next, | |
2639 | .stop = t_stop, | |
2640 | .show = t_show, | |
bc0c38d1 SR |
2641 | }; |
2642 | ||
2643 | static int show_traces_open(struct inode *inode, struct file *file) | |
2644 | { | |
60a11774 SR |
2645 | if (tracing_disabled) |
2646 | return -ENODEV; | |
2647 | ||
f129e965 | 2648 | return seq_open(file, &show_traces_seq_ops); |
bc0c38d1 SR |
2649 | } |
2650 | ||
4acd4d00 SR |
2651 | static ssize_t |
2652 | tracing_write_stub(struct file *filp, const char __user *ubuf, | |
2653 | size_t count, loff_t *ppos) | |
2654 | { | |
2655 | return count; | |
2656 | } | |
2657 | ||
364829b1 SP |
2658 | static loff_t tracing_seek(struct file *file, loff_t offset, int origin) |
2659 | { | |
2660 | if (file->f_mode & FMODE_READ) | |
2661 | return seq_lseek(file, offset, origin); | |
2662 | else | |
2663 | return 0; | |
2664 | } | |
2665 | ||
5e2336a0 | 2666 | static const struct file_operations tracing_fops = { |
4bf39a94 IM |
2667 | .open = tracing_open, |
2668 | .read = seq_read, | |
4acd4d00 | 2669 | .write = tracing_write_stub, |
364829b1 | 2670 | .llseek = tracing_seek, |
4bf39a94 | 2671 | .release = tracing_release, |
bc0c38d1 SR |
2672 | }; |
2673 | ||
5e2336a0 | 2674 | static const struct file_operations show_traces_fops = { |
c7078de1 IM |
2675 | .open = show_traces_open, |
2676 | .read = seq_read, | |
2677 | .release = seq_release, | |
b444786f | 2678 | .llseek = seq_lseek, |
c7078de1 IM |
2679 | }; |
2680 | ||
36dfe925 IM |
2681 | /* |
2682 | * Only trace on a CPU if the bitmask is set: | |
2683 | */ | |
9e01c1b7 | 2684 | static cpumask_var_t tracing_cpumask; |
36dfe925 IM |
2685 | |
2686 | /* | |
2687 | * The tracer itself will not take this lock, but still we want | |
2688 | * to provide a consistent cpumask to user-space: | |
2689 | */ | |
2690 | static DEFINE_MUTEX(tracing_cpumask_update_lock); | |
2691 | ||
2692 | /* | |
2693 | * Temporary storage for the character representation of the | |
2694 | * CPU bitmask (and one more byte for the newline): | |
2695 | */ | |
2696 | static char mask_str[NR_CPUS + 1]; | |
2697 | ||
c7078de1 IM |
2698 | static ssize_t |
2699 | tracing_cpumask_read(struct file *filp, char __user *ubuf, | |
2700 | size_t count, loff_t *ppos) | |
2701 | { | |
36dfe925 | 2702 | int len; |
c7078de1 IM |
2703 | |
2704 | mutex_lock(&tracing_cpumask_update_lock); | |
36dfe925 | 2705 | |
9e01c1b7 | 2706 | len = cpumask_scnprintf(mask_str, count, tracing_cpumask); |
36dfe925 IM |
2707 | if (count - len < 2) { |
2708 | count = -EINVAL; | |
2709 | goto out_err; | |
2710 | } | |
2711 | len += sprintf(mask_str + len, "\n"); | |
2712 | count = simple_read_from_buffer(ubuf, count, ppos, mask_str, NR_CPUS+1); | |
2713 | ||
2714 | out_err: | |
c7078de1 IM |
2715 | mutex_unlock(&tracing_cpumask_update_lock); |
2716 | ||
2717 | return count; | |
2718 | } | |
2719 | ||
2720 | static ssize_t | |
2721 | tracing_cpumask_write(struct file *filp, const char __user *ubuf, | |
2722 | size_t count, loff_t *ppos) | |
2723 | { | |
36dfe925 | 2724 | int err, cpu; |
9e01c1b7 RR |
2725 | cpumask_var_t tracing_cpumask_new; |
2726 | ||
2727 | if (!alloc_cpumask_var(&tracing_cpumask_new, GFP_KERNEL)) | |
2728 | return -ENOMEM; | |
c7078de1 | 2729 | |
9e01c1b7 | 2730 | err = cpumask_parse_user(ubuf, count, tracing_cpumask_new); |
c7078de1 | 2731 | if (err) |
36dfe925 IM |
2732 | goto err_unlock; |
2733 | ||
215368e8 LZ |
2734 | mutex_lock(&tracing_cpumask_update_lock); |
2735 | ||
a5e25883 | 2736 | local_irq_disable(); |
0199c4e6 | 2737 | arch_spin_lock(&ftrace_max_lock); |
ab46428c | 2738 | for_each_tracing_cpu(cpu) { |
36dfe925 IM |
2739 | /* |
2740 | * Increase/decrease the disabled counter if we are | |
2741 | * about to flip a bit in the cpumask: | |
2742 | */ | |
9e01c1b7 RR |
2743 | if (cpumask_test_cpu(cpu, tracing_cpumask) && |
2744 | !cpumask_test_cpu(cpu, tracing_cpumask_new)) { | |
36dfe925 | 2745 | atomic_inc(&global_trace.data[cpu]->disabled); |
71babb27 | 2746 | ring_buffer_record_disable_cpu(global_trace.buffer, cpu); |
36dfe925 | 2747 | } |
9e01c1b7 RR |
2748 | if (!cpumask_test_cpu(cpu, tracing_cpumask) && |
2749 | cpumask_test_cpu(cpu, tracing_cpumask_new)) { | |
36dfe925 | 2750 | atomic_dec(&global_trace.data[cpu]->disabled); |
71babb27 | 2751 | ring_buffer_record_enable_cpu(global_trace.buffer, cpu); |
36dfe925 IM |
2752 | } |
2753 | } | |
0199c4e6 | 2754 | arch_spin_unlock(&ftrace_max_lock); |
a5e25883 | 2755 | local_irq_enable(); |
36dfe925 | 2756 | |
9e01c1b7 | 2757 | cpumask_copy(tracing_cpumask, tracing_cpumask_new); |
36dfe925 IM |
2758 | |
2759 | mutex_unlock(&tracing_cpumask_update_lock); | |
9e01c1b7 | 2760 | free_cpumask_var(tracing_cpumask_new); |
c7078de1 IM |
2761 | |
2762 | return count; | |
36dfe925 IM |
2763 | |
2764 | err_unlock: | |
215368e8 | 2765 | free_cpumask_var(tracing_cpumask_new); |
36dfe925 IM |
2766 | |
2767 | return err; | |
c7078de1 IM |
2768 | } |
2769 | ||
5e2336a0 | 2770 | static const struct file_operations tracing_cpumask_fops = { |
c7078de1 IM |
2771 | .open = tracing_open_generic, |
2772 | .read = tracing_cpumask_read, | |
2773 | .write = tracing_cpumask_write, | |
b444786f | 2774 | .llseek = generic_file_llseek, |
bc0c38d1 SR |
2775 | }; |
2776 | ||
fdb372ed | 2777 | static int tracing_trace_options_show(struct seq_file *m, void *v) |
bc0c38d1 | 2778 | { |
d8e83d26 SR |
2779 | struct tracer_opt *trace_opts; |
2780 | u32 tracer_flags; | |
d8e83d26 | 2781 | int i; |
adf9f195 | 2782 | |
d8e83d26 SR |
2783 | mutex_lock(&trace_types_lock); |
2784 | tracer_flags = current_trace->flags->val; | |
2785 | trace_opts = current_trace->flags->opts; | |
2786 | ||
bc0c38d1 SR |
2787 | for (i = 0; trace_options[i]; i++) { |
2788 | if (trace_flags & (1 << i)) | |
fdb372ed | 2789 | seq_printf(m, "%s\n", trace_options[i]); |
bc0c38d1 | 2790 | else |
fdb372ed | 2791 | seq_printf(m, "no%s\n", trace_options[i]); |
bc0c38d1 SR |
2792 | } |
2793 | ||
adf9f195 FW |
2794 | for (i = 0; trace_opts[i].name; i++) { |
2795 | if (tracer_flags & trace_opts[i].bit) | |
fdb372ed | 2796 | seq_printf(m, "%s\n", trace_opts[i].name); |
adf9f195 | 2797 | else |
fdb372ed | 2798 | seq_printf(m, "no%s\n", trace_opts[i].name); |
adf9f195 | 2799 | } |
d8e83d26 | 2800 | mutex_unlock(&trace_types_lock); |
adf9f195 | 2801 | |
fdb372ed | 2802 | return 0; |
bc0c38d1 | 2803 | } |
bc0c38d1 | 2804 | |
8d18eaaf LZ |
2805 | static int __set_tracer_option(struct tracer *trace, |
2806 | struct tracer_flags *tracer_flags, | |
2807 | struct tracer_opt *opts, int neg) | |
2808 | { | |
2809 | int ret; | |
bc0c38d1 | 2810 | |
8d18eaaf LZ |
2811 | ret = trace->set_flag(tracer_flags->val, opts->bit, !neg); |
2812 | if (ret) | |
2813 | return ret; | |
2814 | ||
2815 | if (neg) | |
2816 | tracer_flags->val &= ~opts->bit; | |
2817 | else | |
2818 | tracer_flags->val |= opts->bit; | |
2819 | return 0; | |
bc0c38d1 SR |
2820 | } |
2821 | ||
adf9f195 FW |
2822 | /* Try to assign a tracer specific option */ |
2823 | static int set_tracer_option(struct tracer *trace, char *cmp, int neg) | |
2824 | { | |
7770841e | 2825 | struct tracer_flags *tracer_flags = trace->flags; |
adf9f195 | 2826 | struct tracer_opt *opts = NULL; |
8d18eaaf | 2827 | int i; |
adf9f195 | 2828 | |
7770841e Z |
2829 | for (i = 0; tracer_flags->opts[i].name; i++) { |
2830 | opts = &tracer_flags->opts[i]; | |
adf9f195 | 2831 | |
8d18eaaf LZ |
2832 | if (strcmp(cmp, opts->name) == 0) |
2833 | return __set_tracer_option(trace, trace->flags, | |
2834 | opts, neg); | |
adf9f195 | 2835 | } |
adf9f195 | 2836 | |
8d18eaaf | 2837 | return -EINVAL; |
adf9f195 FW |
2838 | } |
2839 | ||
af4617bd SR |
2840 | static void set_tracer_flags(unsigned int mask, int enabled) |
2841 | { | |
2842 | /* do nothing if flag is already set */ | |
2843 | if (!!(trace_flags & mask) == !!enabled) | |
2844 | return; | |
2845 | ||
2846 | if (enabled) | |
2847 | trace_flags |= mask; | |
2848 | else | |
2849 | trace_flags &= ~mask; | |
e870e9a1 LZ |
2850 | |
2851 | if (mask == TRACE_ITER_RECORD_CMD) | |
2852 | trace_event_enable_cmd_record(enabled); | |
750912fa DS |
2853 | |
2854 | if (mask == TRACE_ITER_OVERWRITE) | |
2855 | ring_buffer_change_overwrite(global_trace.buffer, enabled); | |
81698831 SR |
2856 | |
2857 | if (mask == TRACE_ITER_PRINTK) | |
2858 | trace_printk_start_stop_comm(enabled); | |
af4617bd SR |
2859 | } |
2860 | ||
7bcfaf54 | 2861 | static int trace_set_options(char *option) |
bc0c38d1 | 2862 | { |
8d18eaaf | 2863 | char *cmp; |
bc0c38d1 | 2864 | int neg = 0; |
7bcfaf54 | 2865 | int ret = 0; |
bc0c38d1 SR |
2866 | int i; |
2867 | ||
7bcfaf54 | 2868 | cmp = strstrip(option); |
bc0c38d1 | 2869 | |
8d18eaaf | 2870 | if (strncmp(cmp, "no", 2) == 0) { |
bc0c38d1 SR |
2871 | neg = 1; |
2872 | cmp += 2; | |
2873 | } | |
2874 | ||
2875 | for (i = 0; trace_options[i]; i++) { | |
8d18eaaf | 2876 | if (strcmp(cmp, trace_options[i]) == 0) { |
af4617bd | 2877 | set_tracer_flags(1 << i, !neg); |
bc0c38d1 SR |
2878 | break; |
2879 | } | |
2880 | } | |
adf9f195 FW |
2881 | |
2882 | /* If no option could be set, test the specific tracer options */ | |
2883 | if (!trace_options[i]) { | |
d8e83d26 | 2884 | mutex_lock(&trace_types_lock); |
adf9f195 | 2885 | ret = set_tracer_option(current_trace, cmp, neg); |
d8e83d26 | 2886 | mutex_unlock(&trace_types_lock); |
adf9f195 | 2887 | } |
bc0c38d1 | 2888 | |
7bcfaf54 SR |
2889 | return ret; |
2890 | } | |
2891 | ||
2892 | static ssize_t | |
2893 | tracing_trace_options_write(struct file *filp, const char __user *ubuf, | |
2894 | size_t cnt, loff_t *ppos) | |
2895 | { | |
2896 | char buf[64]; | |
2897 | ||
2898 | if (cnt >= sizeof(buf)) | |
2899 | return -EINVAL; | |
2900 | ||
2901 | if (copy_from_user(&buf, ubuf, cnt)) | |
2902 | return -EFAULT; | |
2903 | ||
a8dd2176 SR |
2904 | buf[cnt] = 0; |
2905 | ||
7bcfaf54 SR |
2906 | trace_set_options(buf); |
2907 | ||
cf8517cf | 2908 | *ppos += cnt; |
bc0c38d1 SR |
2909 | |
2910 | return cnt; | |
2911 | } | |
2912 | ||
fdb372ed LZ |
2913 | static int tracing_trace_options_open(struct inode *inode, struct file *file) |
2914 | { | |
2915 | if (tracing_disabled) | |
2916 | return -ENODEV; | |
2917 | return single_open(file, tracing_trace_options_show, NULL); | |
2918 | } | |
2919 | ||
5e2336a0 | 2920 | static const struct file_operations tracing_iter_fops = { |
fdb372ed LZ |
2921 | .open = tracing_trace_options_open, |
2922 | .read = seq_read, | |
2923 | .llseek = seq_lseek, | |
2924 | .release = single_release, | |
ee6bce52 | 2925 | .write = tracing_trace_options_write, |
bc0c38d1 SR |
2926 | }; |
2927 | ||
7bd2f24c IM |
2928 | static const char readme_msg[] = |
2929 | "tracing mini-HOWTO:\n\n" | |
156f5a78 GL |
2930 | "# mount -t debugfs nodev /sys/kernel/debug\n\n" |
2931 | "# cat /sys/kernel/debug/tracing/available_tracers\n" | |
1e42e83f | 2932 | "wakeup wakeup_rt preemptirqsoff preemptoff irqsoff function nop\n\n" |
156f5a78 | 2933 | "# cat /sys/kernel/debug/tracing/current_tracer\n" |
bc2b6871 | 2934 | "nop\n" |
1e42e83f | 2935 | "# echo wakeup > /sys/kernel/debug/tracing/current_tracer\n" |
156f5a78 | 2936 | "# cat /sys/kernel/debug/tracing/current_tracer\n" |
1e42e83f | 2937 | "wakeup\n" |
156f5a78 | 2938 | "# cat /sys/kernel/debug/tracing/trace_options\n" |
7bd2f24c | 2939 | "noprint-parent nosym-offset nosym-addr noverbose\n" |
156f5a78 | 2940 | "# echo print-parent > /sys/kernel/debug/tracing/trace_options\n" |
9b5f8b31 | 2941 | "# echo 1 > /sys/kernel/debug/tracing/tracing_on\n" |
156f5a78 | 2942 | "# cat /sys/kernel/debug/tracing/trace > /tmp/trace.txt\n" |
9b5f8b31 | 2943 | "# echo 0 > /sys/kernel/debug/tracing/tracing_on\n" |
7bd2f24c IM |
2944 | ; |
2945 | ||
2946 | static ssize_t | |
2947 | tracing_readme_read(struct file *filp, char __user *ubuf, | |
2948 | size_t cnt, loff_t *ppos) | |
2949 | { | |
2950 | return simple_read_from_buffer(ubuf, cnt, ppos, | |
2951 | readme_msg, strlen(readme_msg)); | |
2952 | } | |
2953 | ||
5e2336a0 | 2954 | static const struct file_operations tracing_readme_fops = { |
c7078de1 IM |
2955 | .open = tracing_open_generic, |
2956 | .read = tracing_readme_read, | |
b444786f | 2957 | .llseek = generic_file_llseek, |
7bd2f24c IM |
2958 | }; |
2959 | ||
69abe6a5 AP |
2960 | static ssize_t |
2961 | tracing_saved_cmdlines_read(struct file *file, char __user *ubuf, | |
2962 | size_t cnt, loff_t *ppos) | |
2963 | { | |
2964 | char *buf_comm; | |
2965 | char *file_buf; | |
2966 | char *buf; | |
2967 | int len = 0; | |
2968 | int pid; | |
2969 | int i; | |
2970 | ||
2971 | file_buf = kmalloc(SAVED_CMDLINES*(16+TASK_COMM_LEN), GFP_KERNEL); | |
2972 | if (!file_buf) | |
2973 | return -ENOMEM; | |
2974 | ||
2975 | buf_comm = kmalloc(TASK_COMM_LEN, GFP_KERNEL); | |
2976 | if (!buf_comm) { | |
2977 | kfree(file_buf); | |
2978 | return -ENOMEM; | |
2979 | } | |
2980 | ||
2981 | buf = file_buf; | |
2982 | ||
2983 | for (i = 0; i < SAVED_CMDLINES; i++) { | |
2984 | int r; | |
2985 | ||
2986 | pid = map_cmdline_to_pid[i]; | |
2987 | if (pid == -1 || pid == NO_CMDLINE_MAP) | |
2988 | continue; | |
2989 | ||
2990 | trace_find_cmdline(pid, buf_comm); | |
2991 | r = sprintf(buf, "%d %s\n", pid, buf_comm); | |
2992 | buf += r; | |
2993 | len += r; | |
2994 | } | |
2995 | ||
2996 | len = simple_read_from_buffer(ubuf, cnt, ppos, | |
2997 | file_buf, len); | |
2998 | ||
2999 | kfree(file_buf); | |
3000 | kfree(buf_comm); | |
3001 | ||
3002 | return len; | |
3003 | } | |
3004 | ||
3005 | static const struct file_operations tracing_saved_cmdlines_fops = { | |
3006 | .open = tracing_open_generic, | |
3007 | .read = tracing_saved_cmdlines_read, | |
b444786f | 3008 | .llseek = generic_file_llseek, |
69abe6a5 AP |
3009 | }; |
3010 | ||
bc0c38d1 SR |
3011 | static ssize_t |
3012 | tracing_set_trace_read(struct file *filp, char __user *ubuf, | |
3013 | size_t cnt, loff_t *ppos) | |
3014 | { | |
ee6c2c1b | 3015 | char buf[MAX_TRACER_SIZE+2]; |
bc0c38d1 SR |
3016 | int r; |
3017 | ||
3018 | mutex_lock(&trace_types_lock); | |
3019 | if (current_trace) | |
3020 | r = sprintf(buf, "%s\n", current_trace->name); | |
3021 | else | |
3022 | r = sprintf(buf, "\n"); | |
3023 | mutex_unlock(&trace_types_lock); | |
3024 | ||
4bf39a94 | 3025 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, r); |
bc0c38d1 SR |
3026 | } |
3027 | ||
b6f11df2 ACM |
3028 | int tracer_init(struct tracer *t, struct trace_array *tr) |
3029 | { | |
3030 | tracing_reset_online_cpus(tr); | |
3031 | return t->init(tr); | |
3032 | } | |
3033 | ||
438ced17 VN |
3034 | static void set_buffer_entries(struct trace_array *tr, unsigned long val) |
3035 | { | |
3036 | int cpu; | |
3037 | for_each_tracing_cpu(cpu) | |
3038 | tr->data[cpu]->entries = val; | |
3039 | } | |
3040 | ||
d60da506 HT |
3041 | /* resize @tr's buffer to the size of @size_tr's entries */ |
3042 | static int resize_buffer_duplicate_size(struct trace_array *tr, | |
3043 | struct trace_array *size_tr, int cpu_id) | |
3044 | { | |
3045 | int cpu, ret = 0; | |
3046 | ||
3047 | if (cpu_id == RING_BUFFER_ALL_CPUS) { | |
3048 | for_each_tracing_cpu(cpu) { | |
3049 | ret = ring_buffer_resize(tr->buffer, | |
3050 | size_tr->data[cpu]->entries, cpu); | |
3051 | if (ret < 0) | |
3052 | break; | |
3053 | tr->data[cpu]->entries = size_tr->data[cpu]->entries; | |
3054 | } | |
3055 | } else { | |
3056 | ret = ring_buffer_resize(tr->buffer, | |
3057 | size_tr->data[cpu_id]->entries, cpu_id); | |
3058 | if (ret == 0) | |
3059 | tr->data[cpu_id]->entries = | |
3060 | size_tr->data[cpu_id]->entries; | |
3061 | } | |
3062 | ||
3063 | return ret; | |
3064 | } | |
3065 | ||
438ced17 | 3066 | static int __tracing_resize_ring_buffer(unsigned long size, int cpu) |
73c5162a SR |
3067 | { |
3068 | int ret; | |
3069 | ||
3070 | /* | |
3071 | * If kernel or user changes the size of the ring buffer | |
a123c52b SR |
3072 | * we use the size that was given, and we can forget about |
3073 | * expanding it later. | |
73c5162a SR |
3074 | */ |
3075 | ring_buffer_expanded = 1; | |
3076 | ||
b382ede6 SR |
3077 | /* May be called before buffers are initialized */ |
3078 | if (!global_trace.buffer) | |
3079 | return 0; | |
3080 | ||
438ced17 | 3081 | ret = ring_buffer_resize(global_trace.buffer, size, cpu); |
73c5162a SR |
3082 | if (ret < 0) |
3083 | return ret; | |
3084 | ||
ef710e10 KM |
3085 | if (!current_trace->use_max_tr) |
3086 | goto out; | |
3087 | ||
438ced17 | 3088 | ret = ring_buffer_resize(max_tr.buffer, size, cpu); |
73c5162a | 3089 | if (ret < 0) { |
d60da506 HT |
3090 | int r = resize_buffer_duplicate_size(&global_trace, |
3091 | &global_trace, cpu); | |
73c5162a | 3092 | if (r < 0) { |
a123c52b SR |
3093 | /* |
3094 | * AARGH! We are left with different | |
3095 | * size max buffer!!!! | |
3096 | * The max buffer is our "snapshot" buffer. | |
3097 | * When a tracer needs a snapshot (one of the | |
3098 | * latency tracers), it swaps the max buffer | |
3099 | * with the saved snap shot. We succeeded to | |
3100 | * update the size of the main buffer, but failed to | |
3101 | * update the size of the max buffer. But when we tried | |
3102 | * to reset the main buffer to the original size, we | |
3103 | * failed there too. This is very unlikely to | |
3104 | * happen, but if it does, warn and kill all | |
3105 | * tracing. | |
3106 | */ | |
73c5162a SR |
3107 | WARN_ON(1); |
3108 | tracing_disabled = 1; | |
3109 | } | |
3110 | return ret; | |
3111 | } | |
3112 | ||
438ced17 VN |
3113 | if (cpu == RING_BUFFER_ALL_CPUS) |
3114 | set_buffer_entries(&max_tr, size); | |
3115 | else | |
3116 | max_tr.data[cpu]->entries = size; | |
3117 | ||
ef710e10 | 3118 | out: |
438ced17 VN |
3119 | if (cpu == RING_BUFFER_ALL_CPUS) |
3120 | set_buffer_entries(&global_trace, size); | |
3121 | else | |
3122 | global_trace.data[cpu]->entries = size; | |
73c5162a SR |
3123 | |
3124 | return ret; | |
3125 | } | |
3126 | ||
438ced17 | 3127 | static ssize_t tracing_resize_ring_buffer(unsigned long size, int cpu_id) |
4f271a2a | 3128 | { |
83f40318 | 3129 | int ret = size; |
4f271a2a VN |
3130 | |
3131 | mutex_lock(&trace_types_lock); | |
3132 | ||
438ced17 VN |
3133 | if (cpu_id != RING_BUFFER_ALL_CPUS) { |
3134 | /* make sure, this cpu is enabled in the mask */ | |
3135 | if (!cpumask_test_cpu(cpu_id, tracing_buffer_mask)) { | |
3136 | ret = -EINVAL; | |
3137 | goto out; | |
3138 | } | |
3139 | } | |
4f271a2a | 3140 | |
438ced17 | 3141 | ret = __tracing_resize_ring_buffer(size, cpu_id); |
4f271a2a VN |
3142 | if (ret < 0) |
3143 | ret = -ENOMEM; | |
3144 | ||
438ced17 | 3145 | out: |
4f271a2a VN |
3146 | mutex_unlock(&trace_types_lock); |
3147 | ||
3148 | return ret; | |
3149 | } | |
3150 | ||
ef710e10 | 3151 | |
1852fcce SR |
3152 | /** |
3153 | * tracing_update_buffers - used by tracing facility to expand ring buffers | |
3154 | * | |
3155 | * To save on memory when the tracing is never used on a system with it | |
3156 | * configured in. The ring buffers are set to a minimum size. But once | |
3157 | * a user starts to use the tracing facility, then they need to grow | |
3158 | * to their default size. | |
3159 | * | |
3160 | * This function is to be called when a tracer is about to be used. | |
3161 | */ | |
3162 | int tracing_update_buffers(void) | |
3163 | { | |
3164 | int ret = 0; | |
3165 | ||
1027fcb2 | 3166 | mutex_lock(&trace_types_lock); |
1852fcce | 3167 | if (!ring_buffer_expanded) |
438ced17 VN |
3168 | ret = __tracing_resize_ring_buffer(trace_buf_size, |
3169 | RING_BUFFER_ALL_CPUS); | |
1027fcb2 | 3170 | mutex_unlock(&trace_types_lock); |
1852fcce SR |
3171 | |
3172 | return ret; | |
3173 | } | |
3174 | ||
577b785f SR |
3175 | struct trace_option_dentry; |
3176 | ||
3177 | static struct trace_option_dentry * | |
3178 | create_trace_option_files(struct tracer *tracer); | |
3179 | ||
3180 | static void | |
3181 | destroy_trace_option_files(struct trace_option_dentry *topts); | |
3182 | ||
b2821ae6 | 3183 | static int tracing_set_tracer(const char *buf) |
bc0c38d1 | 3184 | { |
577b785f | 3185 | static struct trace_option_dentry *topts; |
bc0c38d1 SR |
3186 | struct trace_array *tr = &global_trace; |
3187 | struct tracer *t; | |
d9e54076 | 3188 | int ret = 0; |
bc0c38d1 | 3189 | |
1027fcb2 SR |
3190 | mutex_lock(&trace_types_lock); |
3191 | ||
73c5162a | 3192 | if (!ring_buffer_expanded) { |
438ced17 VN |
3193 | ret = __tracing_resize_ring_buffer(trace_buf_size, |
3194 | RING_BUFFER_ALL_CPUS); | |
73c5162a | 3195 | if (ret < 0) |
59f586db | 3196 | goto out; |
73c5162a SR |
3197 | ret = 0; |
3198 | } | |
3199 | ||
bc0c38d1 SR |
3200 | for (t = trace_types; t; t = t->next) { |
3201 | if (strcmp(t->name, buf) == 0) | |
3202 | break; | |
3203 | } | |
c2931e05 FW |
3204 | if (!t) { |
3205 | ret = -EINVAL; | |
3206 | goto out; | |
3207 | } | |
3208 | if (t == current_trace) | |
bc0c38d1 SR |
3209 | goto out; |
3210 | ||
9f029e83 | 3211 | trace_branch_disable(); |
bc0c38d1 SR |
3212 | if (current_trace && current_trace->reset) |
3213 | current_trace->reset(tr); | |
ef710e10 KM |
3214 | if (current_trace && current_trace->use_max_tr) { |
3215 | /* | |
3216 | * We don't free the ring buffer. instead, resize it because | |
3217 | * The max_tr ring buffer has some state (e.g. ring->clock) and | |
3218 | * we want preserve it. | |
3219 | */ | |
438ced17 VN |
3220 | ring_buffer_resize(max_tr.buffer, 1, RING_BUFFER_ALL_CPUS); |
3221 | set_buffer_entries(&max_tr, 1); | |
ef710e10 | 3222 | } |
577b785f SR |
3223 | destroy_trace_option_files(topts); |
3224 | ||
b2ad368b | 3225 | current_trace = &nop_trace; |
577b785f | 3226 | |
b2ad368b AV |
3227 | topts = create_trace_option_files(t); |
3228 | if (t->use_max_tr) { | |
438ced17 | 3229 | /* we need to make per cpu buffer sizes equivalent */ |
d60da506 HT |
3230 | ret = resize_buffer_duplicate_size(&max_tr, &global_trace, |
3231 | RING_BUFFER_ALL_CPUS); | |
3232 | if (ret < 0) | |
3233 | goto out; | |
ef710e10 | 3234 | } |
577b785f | 3235 | |
1c80025a | 3236 | if (t->init) { |
b6f11df2 | 3237 | ret = tracer_init(t, tr); |
1c80025a FW |
3238 | if (ret) |
3239 | goto out; | |
3240 | } | |
bc0c38d1 | 3241 | |
b2ad368b | 3242 | current_trace = t; |
9f029e83 | 3243 | trace_branch_enable(tr); |
bc0c38d1 SR |
3244 | out: |
3245 | mutex_unlock(&trace_types_lock); | |
3246 | ||
d9e54076 PZ |
3247 | return ret; |
3248 | } | |
3249 | ||
3250 | static ssize_t | |
3251 | tracing_set_trace_write(struct file *filp, const char __user *ubuf, | |
3252 | size_t cnt, loff_t *ppos) | |
3253 | { | |
ee6c2c1b | 3254 | char buf[MAX_TRACER_SIZE+1]; |
d9e54076 PZ |
3255 | int i; |
3256 | size_t ret; | |
e6e7a65a FW |
3257 | int err; |
3258 | ||
3259 | ret = cnt; | |
d9e54076 | 3260 | |
ee6c2c1b LZ |
3261 | if (cnt > MAX_TRACER_SIZE) |
3262 | cnt = MAX_TRACER_SIZE; | |
d9e54076 PZ |
3263 | |
3264 | if (copy_from_user(&buf, ubuf, cnt)) | |
3265 | return -EFAULT; | |
3266 | ||
3267 | buf[cnt] = 0; | |
3268 | ||
3269 | /* strip ending whitespace. */ | |
3270 | for (i = cnt - 1; i > 0 && isspace(buf[i]); i--) | |
3271 | buf[i] = 0; | |
3272 | ||
e6e7a65a FW |
3273 | err = tracing_set_tracer(buf); |
3274 | if (err) | |
3275 | return err; | |
d9e54076 | 3276 | |
cf8517cf | 3277 | *ppos += ret; |
bc0c38d1 | 3278 | |
c2931e05 | 3279 | return ret; |
bc0c38d1 SR |
3280 | } |
3281 | ||
3282 | static ssize_t | |
3283 | tracing_max_lat_read(struct file *filp, char __user *ubuf, | |
3284 | size_t cnt, loff_t *ppos) | |
3285 | { | |
3286 | unsigned long *ptr = filp->private_data; | |
3287 | char buf[64]; | |
3288 | int r; | |
3289 | ||
cffae437 | 3290 | r = snprintf(buf, sizeof(buf), "%ld\n", |
bc0c38d1 | 3291 | *ptr == (unsigned long)-1 ? -1 : nsecs_to_usecs(*ptr)); |
cffae437 SR |
3292 | if (r > sizeof(buf)) |
3293 | r = sizeof(buf); | |
4bf39a94 | 3294 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, r); |
bc0c38d1 SR |
3295 | } |
3296 | ||
3297 | static ssize_t | |
3298 | tracing_max_lat_write(struct file *filp, const char __user *ubuf, | |
3299 | size_t cnt, loff_t *ppos) | |
3300 | { | |
5e39841c | 3301 | unsigned long *ptr = filp->private_data; |
5e39841c | 3302 | unsigned long val; |
c6caeeb1 | 3303 | int ret; |
bc0c38d1 | 3304 | |
22fe9b54 PH |
3305 | ret = kstrtoul_from_user(ubuf, cnt, 10, &val); |
3306 | if (ret) | |
c6caeeb1 | 3307 | return ret; |
bc0c38d1 SR |
3308 | |
3309 | *ptr = val * 1000; | |
3310 | ||
3311 | return cnt; | |
3312 | } | |
3313 | ||
b3806b43 SR |
3314 | static int tracing_open_pipe(struct inode *inode, struct file *filp) |
3315 | { | |
b04cc6b1 | 3316 | long cpu_file = (long) inode->i_private; |
b3806b43 | 3317 | struct trace_iterator *iter; |
b04cc6b1 | 3318 | int ret = 0; |
b3806b43 SR |
3319 | |
3320 | if (tracing_disabled) | |
3321 | return -ENODEV; | |
3322 | ||
b04cc6b1 FW |
3323 | mutex_lock(&trace_types_lock); |
3324 | ||
b3806b43 SR |
3325 | /* create a buffer to store the information to pass to userspace */ |
3326 | iter = kzalloc(sizeof(*iter), GFP_KERNEL); | |
b04cc6b1 FW |
3327 | if (!iter) { |
3328 | ret = -ENOMEM; | |
3329 | goto out; | |
3330 | } | |
b3806b43 | 3331 | |
d7350c3f FW |
3332 | /* |
3333 | * We make a copy of the current tracer to avoid concurrent | |
3334 | * changes on it while we are reading. | |
3335 | */ | |
3336 | iter->trace = kmalloc(sizeof(*iter->trace), GFP_KERNEL); | |
3337 | if (!iter->trace) { | |
3338 | ret = -ENOMEM; | |
3339 | goto fail; | |
3340 | } | |
3341 | if (current_trace) | |
3342 | *iter->trace = *current_trace; | |
3343 | ||
4462344e | 3344 | if (!alloc_cpumask_var(&iter->started, GFP_KERNEL)) { |
b04cc6b1 | 3345 | ret = -ENOMEM; |
d7350c3f | 3346 | goto fail; |
4462344e RR |
3347 | } |
3348 | ||
a309720c | 3349 | /* trace pipe does not show start of buffer */ |
4462344e | 3350 | cpumask_setall(iter->started); |
a309720c | 3351 | |
112f38a7 SR |
3352 | if (trace_flags & TRACE_ITER_LATENCY_FMT) |
3353 | iter->iter_flags |= TRACE_FILE_LAT_FMT; | |
3354 | ||
8be0709f DS |
3355 | /* Output in nanoseconds only if we are using a clock in nanoseconds. */ |
3356 | if (trace_clocks[trace_clock_id].in_ns) | |
3357 | iter->iter_flags |= TRACE_FILE_TIME_IN_NS; | |
3358 | ||
b04cc6b1 | 3359 | iter->cpu_file = cpu_file; |
b3806b43 | 3360 | iter->tr = &global_trace; |
d7350c3f | 3361 | mutex_init(&iter->mutex); |
b3806b43 SR |
3362 | filp->private_data = iter; |
3363 | ||
107bad8b SR |
3364 | if (iter->trace->pipe_open) |
3365 | iter->trace->pipe_open(iter); | |
107bad8b | 3366 | |
b444786f | 3367 | nonseekable_open(inode, filp); |
b04cc6b1 FW |
3368 | out: |
3369 | mutex_unlock(&trace_types_lock); | |
3370 | return ret; | |
d7350c3f FW |
3371 | |
3372 | fail: | |
3373 | kfree(iter->trace); | |
3374 | kfree(iter); | |
3375 | mutex_unlock(&trace_types_lock); | |
3376 | return ret; | |
b3806b43 SR |
3377 | } |
3378 | ||
3379 | static int tracing_release_pipe(struct inode *inode, struct file *file) | |
3380 | { | |
3381 | struct trace_iterator *iter = file->private_data; | |
3382 | ||
b04cc6b1 FW |
3383 | mutex_lock(&trace_types_lock); |
3384 | ||
29bf4a5e | 3385 | if (iter->trace->pipe_close) |
c521efd1 SR |
3386 | iter->trace->pipe_close(iter); |
3387 | ||
b04cc6b1 FW |
3388 | mutex_unlock(&trace_types_lock); |
3389 | ||
4462344e | 3390 | free_cpumask_var(iter->started); |
d7350c3f FW |
3391 | mutex_destroy(&iter->mutex); |
3392 | kfree(iter->trace); | |
b3806b43 | 3393 | kfree(iter); |
b3806b43 SR |
3394 | |
3395 | return 0; | |
3396 | } | |
3397 | ||
2a2cc8f7 SSP |
3398 | static unsigned int |
3399 | tracing_poll_pipe(struct file *filp, poll_table *poll_table) | |
3400 | { | |
3401 | struct trace_iterator *iter = filp->private_data; | |
3402 | ||
3403 | if (trace_flags & TRACE_ITER_BLOCK) { | |
3404 | /* | |
3405 | * Always select as readable when in blocking mode | |
3406 | */ | |
3407 | return POLLIN | POLLRDNORM; | |
afc2abc0 | 3408 | } else { |
2a2cc8f7 SSP |
3409 | if (!trace_empty(iter)) |
3410 | return POLLIN | POLLRDNORM; | |
3411 | poll_wait(filp, &trace_wait, poll_table); | |
3412 | if (!trace_empty(iter)) | |
3413 | return POLLIN | POLLRDNORM; | |
3414 | ||
3415 | return 0; | |
3416 | } | |
3417 | } | |
3418 | ||
6eaaa5d5 FW |
3419 | /* |
3420 | * This is a make-shift waitqueue. | |
3421 | * A tracer might use this callback on some rare cases: | |
3422 | * | |
3423 | * 1) the current tracer might hold the runqueue lock when it wakes up | |
3424 | * a reader, hence a deadlock (sched, function, and function graph tracers) | |
3425 | * 2) the function tracers, trace all functions, we don't want | |
3426 | * the overhead of calling wake_up and friends | |
3427 | * (and tracing them too) | |
3428 | * | |
3429 | * Anyway, this is really very primitive wakeup. | |
3430 | */ | |
3431 | void poll_wait_pipe(struct trace_iterator *iter) | |
3432 | { | |
3433 | set_current_state(TASK_INTERRUPTIBLE); | |
3434 | /* sleep for 100 msecs, and try again. */ | |
3435 | schedule_timeout(HZ / 10); | |
3436 | } | |
3437 | ||
ff98781b EGM |
3438 | /* Must be called with trace_types_lock mutex held. */ |
3439 | static int tracing_wait_pipe(struct file *filp) | |
b3806b43 SR |
3440 | { |
3441 | struct trace_iterator *iter = filp->private_data; | |
b3806b43 | 3442 | |
b3806b43 | 3443 | while (trace_empty(iter)) { |
2dc8f095 | 3444 | |
107bad8b | 3445 | if ((filp->f_flags & O_NONBLOCK)) { |
ff98781b | 3446 | return -EAGAIN; |
107bad8b | 3447 | } |
2dc8f095 | 3448 | |
d7350c3f | 3449 | mutex_unlock(&iter->mutex); |
107bad8b | 3450 | |
6eaaa5d5 | 3451 | iter->trace->wait_pipe(iter); |
b3806b43 | 3452 | |
d7350c3f | 3453 | mutex_lock(&iter->mutex); |
107bad8b | 3454 | |
6eaaa5d5 | 3455 | if (signal_pending(current)) |
ff98781b | 3456 | return -EINTR; |
b3806b43 SR |
3457 | |
3458 | /* | |
250bfd3d | 3459 | * We block until we read something and tracing is disabled. |
b3806b43 SR |
3460 | * We still block if tracing is disabled, but we have never |
3461 | * read anything. This allows a user to cat this file, and | |
3462 | * then enable tracing. But after we have read something, | |
3463 | * we give an EOF when tracing is again disabled. | |
3464 | * | |
3465 | * iter->pos will be 0 if we haven't read anything. | |
3466 | */ | |
250bfd3d | 3467 | if (!tracing_is_enabled() && iter->pos) |
b3806b43 | 3468 | break; |
b3806b43 SR |
3469 | } |
3470 | ||
ff98781b EGM |
3471 | return 1; |
3472 | } | |
3473 | ||
3474 | /* | |
3475 | * Consumer reader. | |
3476 | */ | |
3477 | static ssize_t | |
3478 | tracing_read_pipe(struct file *filp, char __user *ubuf, | |
3479 | size_t cnt, loff_t *ppos) | |
3480 | { | |
3481 | struct trace_iterator *iter = filp->private_data; | |
d7350c3f | 3482 | static struct tracer *old_tracer; |
ff98781b EGM |
3483 | ssize_t sret; |
3484 | ||
3485 | /* return any leftover data */ | |
3486 | sret = trace_seq_to_user(&iter->seq, ubuf, cnt); | |
3487 | if (sret != -EBUSY) | |
3488 | return sret; | |
3489 | ||
f9520750 | 3490 | trace_seq_init(&iter->seq); |
ff98781b | 3491 | |
d7350c3f | 3492 | /* copy the tracer to avoid using a global lock all around */ |
ff98781b | 3493 | mutex_lock(&trace_types_lock); |
d7350c3f FW |
3494 | if (unlikely(old_tracer != current_trace && current_trace)) { |
3495 | old_tracer = current_trace; | |
3496 | *iter->trace = *current_trace; | |
3497 | } | |
3498 | mutex_unlock(&trace_types_lock); | |
3499 | ||
3500 | /* | |
3501 | * Avoid more than one consumer on a single file descriptor | |
3502 | * This is just a matter of traces coherency, the ring buffer itself | |
3503 | * is protected. | |
3504 | */ | |
3505 | mutex_lock(&iter->mutex); | |
ff98781b EGM |
3506 | if (iter->trace->read) { |
3507 | sret = iter->trace->read(iter, filp, ubuf, cnt, ppos); | |
3508 | if (sret) | |
3509 | goto out; | |
3510 | } | |
3511 | ||
3512 | waitagain: | |
3513 | sret = tracing_wait_pipe(filp); | |
3514 | if (sret <= 0) | |
3515 | goto out; | |
3516 | ||
b3806b43 | 3517 | /* stop when tracing is finished */ |
ff98781b EGM |
3518 | if (trace_empty(iter)) { |
3519 | sret = 0; | |
107bad8b | 3520 | goto out; |
ff98781b | 3521 | } |
b3806b43 SR |
3522 | |
3523 | if (cnt >= PAGE_SIZE) | |
3524 | cnt = PAGE_SIZE - 1; | |
3525 | ||
53d0aa77 | 3526 | /* reset all but tr, trace, and overruns */ |
53d0aa77 SR |
3527 | memset(&iter->seq, 0, |
3528 | sizeof(struct trace_iterator) - | |
3529 | offsetof(struct trace_iterator, seq)); | |
4823ed7e | 3530 | iter->pos = -1; |
b3806b43 | 3531 | |
4f535968 | 3532 | trace_event_read_lock(); |
7e53bd42 | 3533 | trace_access_lock(iter->cpu_file); |
955b61e5 | 3534 | while (trace_find_next_entry_inc(iter) != NULL) { |
2c4f035f | 3535 | enum print_line_t ret; |
088b1e42 SR |
3536 | int len = iter->seq.len; |
3537 | ||
f9896bf3 | 3538 | ret = print_trace_line(iter); |
2c4f035f | 3539 | if (ret == TRACE_TYPE_PARTIAL_LINE) { |
088b1e42 SR |
3540 | /* don't print partial lines */ |
3541 | iter->seq.len = len; | |
b3806b43 | 3542 | break; |
088b1e42 | 3543 | } |
b91facc3 FW |
3544 | if (ret != TRACE_TYPE_NO_CONSUME) |
3545 | trace_consume(iter); | |
b3806b43 SR |
3546 | |
3547 | if (iter->seq.len >= cnt) | |
3548 | break; | |
ee5e51f5 JO |
3549 | |
3550 | /* | |
3551 | * Setting the full flag means we reached the trace_seq buffer | |
3552 | * size and we should leave by partial output condition above. | |
3553 | * One of the trace_seq_* functions is not used properly. | |
3554 | */ | |
3555 | WARN_ONCE(iter->seq.full, "full flag set for trace type %d", | |
3556 | iter->ent->type); | |
b3806b43 | 3557 | } |
7e53bd42 | 3558 | trace_access_unlock(iter->cpu_file); |
4f535968 | 3559 | trace_event_read_unlock(); |
b3806b43 | 3560 | |
b3806b43 | 3561 | /* Now copy what we have to the user */ |
6c6c2796 PP |
3562 | sret = trace_seq_to_user(&iter->seq, ubuf, cnt); |
3563 | if (iter->seq.readpos >= iter->seq.len) | |
f9520750 | 3564 | trace_seq_init(&iter->seq); |
9ff4b974 PP |
3565 | |
3566 | /* | |
25985edc | 3567 | * If there was nothing to send to user, in spite of consuming trace |
9ff4b974 PP |
3568 | * entries, go back to wait for more entries. |
3569 | */ | |
6c6c2796 | 3570 | if (sret == -EBUSY) |
9ff4b974 | 3571 | goto waitagain; |
b3806b43 | 3572 | |
107bad8b | 3573 | out: |
d7350c3f | 3574 | mutex_unlock(&iter->mutex); |
107bad8b | 3575 | |
6c6c2796 | 3576 | return sret; |
b3806b43 SR |
3577 | } |
3578 | ||
3c56819b EGM |
3579 | static void tracing_pipe_buf_release(struct pipe_inode_info *pipe, |
3580 | struct pipe_buffer *buf) | |
3581 | { | |
3582 | __free_page(buf->page); | |
3583 | } | |
3584 | ||
3585 | static void tracing_spd_release_pipe(struct splice_pipe_desc *spd, | |
3586 | unsigned int idx) | |
3587 | { | |
3588 | __free_page(spd->pages[idx]); | |
3589 | } | |
3590 | ||
28dfef8f | 3591 | static const struct pipe_buf_operations tracing_pipe_buf_ops = { |
34cd4998 SR |
3592 | .can_merge = 0, |
3593 | .map = generic_pipe_buf_map, | |
3594 | .unmap = generic_pipe_buf_unmap, | |
3595 | .confirm = generic_pipe_buf_confirm, | |
3596 | .release = tracing_pipe_buf_release, | |
3597 | .steal = generic_pipe_buf_steal, | |
3598 | .get = generic_pipe_buf_get, | |
3c56819b EGM |
3599 | }; |
3600 | ||
34cd4998 | 3601 | static size_t |
fa7c7f6e | 3602 | tracing_fill_pipe_page(size_t rem, struct trace_iterator *iter) |
34cd4998 SR |
3603 | { |
3604 | size_t count; | |
3605 | int ret; | |
3606 | ||
3607 | /* Seq buffer is page-sized, exactly what we need. */ | |
3608 | for (;;) { | |
3609 | count = iter->seq.len; | |
3610 | ret = print_trace_line(iter); | |
3611 | count = iter->seq.len - count; | |
3612 | if (rem < count) { | |
3613 | rem = 0; | |
3614 | iter->seq.len -= count; | |
3615 | break; | |
3616 | } | |
3617 | if (ret == TRACE_TYPE_PARTIAL_LINE) { | |
3618 | iter->seq.len -= count; | |
3619 | break; | |
3620 | } | |
3621 | ||
74e7ff8c LJ |
3622 | if (ret != TRACE_TYPE_NO_CONSUME) |
3623 | trace_consume(iter); | |
34cd4998 | 3624 | rem -= count; |
955b61e5 | 3625 | if (!trace_find_next_entry_inc(iter)) { |
34cd4998 SR |
3626 | rem = 0; |
3627 | iter->ent = NULL; | |
3628 | break; | |
3629 | } | |
3630 | } | |
3631 | ||
3632 | return rem; | |
3633 | } | |
3634 | ||
3c56819b EGM |
3635 | static ssize_t tracing_splice_read_pipe(struct file *filp, |
3636 | loff_t *ppos, | |
3637 | struct pipe_inode_info *pipe, | |
3638 | size_t len, | |
3639 | unsigned int flags) | |
3640 | { | |
35f3d14d JA |
3641 | struct page *pages_def[PIPE_DEF_BUFFERS]; |
3642 | struct partial_page partial_def[PIPE_DEF_BUFFERS]; | |
3c56819b EGM |
3643 | struct trace_iterator *iter = filp->private_data; |
3644 | struct splice_pipe_desc spd = { | |
35f3d14d JA |
3645 | .pages = pages_def, |
3646 | .partial = partial_def, | |
34cd4998 | 3647 | .nr_pages = 0, /* This gets updated below. */ |
047fe360 | 3648 | .nr_pages_max = PIPE_DEF_BUFFERS, |
34cd4998 SR |
3649 | .flags = flags, |
3650 | .ops = &tracing_pipe_buf_ops, | |
3651 | .spd_release = tracing_spd_release_pipe, | |
3c56819b | 3652 | }; |
d7350c3f | 3653 | static struct tracer *old_tracer; |
3c56819b | 3654 | ssize_t ret; |
34cd4998 | 3655 | size_t rem; |
3c56819b EGM |
3656 | unsigned int i; |
3657 | ||
35f3d14d JA |
3658 | if (splice_grow_spd(pipe, &spd)) |
3659 | return -ENOMEM; | |
3660 | ||
d7350c3f | 3661 | /* copy the tracer to avoid using a global lock all around */ |
3c56819b | 3662 | mutex_lock(&trace_types_lock); |
d7350c3f FW |
3663 | if (unlikely(old_tracer != current_trace && current_trace)) { |
3664 | old_tracer = current_trace; | |
3665 | *iter->trace = *current_trace; | |
3666 | } | |
3667 | mutex_unlock(&trace_types_lock); | |
3668 | ||
3669 | mutex_lock(&iter->mutex); | |
3c56819b EGM |
3670 | |
3671 | if (iter->trace->splice_read) { | |
3672 | ret = iter->trace->splice_read(iter, filp, | |
3673 | ppos, pipe, len, flags); | |
3674 | if (ret) | |
34cd4998 | 3675 | goto out_err; |
3c56819b EGM |
3676 | } |
3677 | ||
3678 | ret = tracing_wait_pipe(filp); | |
3679 | if (ret <= 0) | |
34cd4998 | 3680 | goto out_err; |
3c56819b | 3681 | |
955b61e5 | 3682 | if (!iter->ent && !trace_find_next_entry_inc(iter)) { |
3c56819b | 3683 | ret = -EFAULT; |
34cd4998 | 3684 | goto out_err; |
3c56819b EGM |
3685 | } |
3686 | ||
4f535968 | 3687 | trace_event_read_lock(); |
7e53bd42 | 3688 | trace_access_lock(iter->cpu_file); |
4f535968 | 3689 | |
3c56819b | 3690 | /* Fill as many pages as possible. */ |
35f3d14d JA |
3691 | for (i = 0, rem = len; i < pipe->buffers && rem; i++) { |
3692 | spd.pages[i] = alloc_page(GFP_KERNEL); | |
3693 | if (!spd.pages[i]) | |
34cd4998 | 3694 | break; |
3c56819b | 3695 | |
fa7c7f6e | 3696 | rem = tracing_fill_pipe_page(rem, iter); |
3c56819b EGM |
3697 | |
3698 | /* Copy the data into the page, so we can start over. */ | |
3699 | ret = trace_seq_to_buffer(&iter->seq, | |
35f3d14d | 3700 | page_address(spd.pages[i]), |
3c56819b EGM |
3701 | iter->seq.len); |
3702 | if (ret < 0) { | |
35f3d14d | 3703 | __free_page(spd.pages[i]); |
3c56819b EGM |
3704 | break; |
3705 | } | |
35f3d14d JA |
3706 | spd.partial[i].offset = 0; |
3707 | spd.partial[i].len = iter->seq.len; | |
3c56819b | 3708 | |
f9520750 | 3709 | trace_seq_init(&iter->seq); |
3c56819b EGM |
3710 | } |
3711 | ||
7e53bd42 | 3712 | trace_access_unlock(iter->cpu_file); |
4f535968 | 3713 | trace_event_read_unlock(); |
d7350c3f | 3714 | mutex_unlock(&iter->mutex); |
3c56819b EGM |
3715 | |
3716 | spd.nr_pages = i; | |
3717 | ||
35f3d14d JA |
3718 | ret = splice_to_pipe(pipe, &spd); |
3719 | out: | |
047fe360 | 3720 | splice_shrink_spd(&spd); |
35f3d14d | 3721 | return ret; |
3c56819b | 3722 | |
34cd4998 | 3723 | out_err: |
d7350c3f | 3724 | mutex_unlock(&iter->mutex); |
35f3d14d | 3725 | goto out; |
3c56819b EGM |
3726 | } |
3727 | ||
438ced17 VN |
3728 | struct ftrace_entries_info { |
3729 | struct trace_array *tr; | |
3730 | int cpu; | |
3731 | }; | |
3732 | ||
3733 | static int tracing_entries_open(struct inode *inode, struct file *filp) | |
3734 | { | |
3735 | struct ftrace_entries_info *info; | |
3736 | ||
3737 | if (tracing_disabled) | |
3738 | return -ENODEV; | |
3739 | ||
3740 | info = kzalloc(sizeof(*info), GFP_KERNEL); | |
3741 | if (!info) | |
3742 | return -ENOMEM; | |
3743 | ||
3744 | info->tr = &global_trace; | |
3745 | info->cpu = (unsigned long)inode->i_private; | |
3746 | ||
3747 | filp->private_data = info; | |
3748 | ||
3749 | return 0; | |
3750 | } | |
3751 | ||
a98a3c3f SR |
3752 | static ssize_t |
3753 | tracing_entries_read(struct file *filp, char __user *ubuf, | |
3754 | size_t cnt, loff_t *ppos) | |
3755 | { | |
438ced17 VN |
3756 | struct ftrace_entries_info *info = filp->private_data; |
3757 | struct trace_array *tr = info->tr; | |
3758 | char buf[64]; | |
3759 | int r = 0; | |
3760 | ssize_t ret; | |
a98a3c3f | 3761 | |
db526ca3 | 3762 | mutex_lock(&trace_types_lock); |
438ced17 VN |
3763 | |
3764 | if (info->cpu == RING_BUFFER_ALL_CPUS) { | |
3765 | int cpu, buf_size_same; | |
3766 | unsigned long size; | |
3767 | ||
3768 | size = 0; | |
3769 | buf_size_same = 1; | |
3770 | /* check if all cpu sizes are same */ | |
3771 | for_each_tracing_cpu(cpu) { | |
3772 | /* fill in the size from first enabled cpu */ | |
3773 | if (size == 0) | |
3774 | size = tr->data[cpu]->entries; | |
3775 | if (size != tr->data[cpu]->entries) { | |
3776 | buf_size_same = 0; | |
3777 | break; | |
3778 | } | |
3779 | } | |
3780 | ||
3781 | if (buf_size_same) { | |
3782 | if (!ring_buffer_expanded) | |
3783 | r = sprintf(buf, "%lu (expanded: %lu)\n", | |
3784 | size >> 10, | |
3785 | trace_buf_size >> 10); | |
3786 | else | |
3787 | r = sprintf(buf, "%lu\n", size >> 10); | |
3788 | } else | |
3789 | r = sprintf(buf, "X\n"); | |
3790 | } else | |
3791 | r = sprintf(buf, "%lu\n", tr->data[info->cpu]->entries >> 10); | |
3792 | ||
db526ca3 SR |
3793 | mutex_unlock(&trace_types_lock); |
3794 | ||
438ced17 VN |
3795 | ret = simple_read_from_buffer(ubuf, cnt, ppos, buf, r); |
3796 | return ret; | |
a98a3c3f SR |
3797 | } |
3798 | ||
3799 | static ssize_t | |
3800 | tracing_entries_write(struct file *filp, const char __user *ubuf, | |
3801 | size_t cnt, loff_t *ppos) | |
3802 | { | |
438ced17 | 3803 | struct ftrace_entries_info *info = filp->private_data; |
a98a3c3f | 3804 | unsigned long val; |
4f271a2a | 3805 | int ret; |
a98a3c3f | 3806 | |
22fe9b54 PH |
3807 | ret = kstrtoul_from_user(ubuf, cnt, 10, &val); |
3808 | if (ret) | |
c6caeeb1 | 3809 | return ret; |
a98a3c3f SR |
3810 | |
3811 | /* must have at least 1 entry */ | |
3812 | if (!val) | |
3813 | return -EINVAL; | |
3814 | ||
1696b2b0 SR |
3815 | /* value is in KB */ |
3816 | val <<= 10; | |
3817 | ||
438ced17 | 3818 | ret = tracing_resize_ring_buffer(val, info->cpu); |
4f271a2a VN |
3819 | if (ret < 0) |
3820 | return ret; | |
a98a3c3f | 3821 | |
cf8517cf | 3822 | *ppos += cnt; |
a98a3c3f | 3823 | |
4f271a2a VN |
3824 | return cnt; |
3825 | } | |
bf5e6519 | 3826 | |
438ced17 VN |
3827 | static int |
3828 | tracing_entries_release(struct inode *inode, struct file *filp) | |
3829 | { | |
3830 | struct ftrace_entries_info *info = filp->private_data; | |
3831 | ||
3832 | kfree(info); | |
3833 | ||
3834 | return 0; | |
3835 | } | |
3836 | ||
f81ab074 VN |
3837 | static ssize_t |
3838 | tracing_total_entries_read(struct file *filp, char __user *ubuf, | |
3839 | size_t cnt, loff_t *ppos) | |
3840 | { | |
3841 | struct trace_array *tr = filp->private_data; | |
3842 | char buf[64]; | |
3843 | int r, cpu; | |
3844 | unsigned long size = 0, expanded_size = 0; | |
3845 | ||
3846 | mutex_lock(&trace_types_lock); | |
3847 | for_each_tracing_cpu(cpu) { | |
438ced17 | 3848 | size += tr->data[cpu]->entries >> 10; |
f81ab074 VN |
3849 | if (!ring_buffer_expanded) |
3850 | expanded_size += trace_buf_size >> 10; | |
3851 | } | |
3852 | if (ring_buffer_expanded) | |
3853 | r = sprintf(buf, "%lu\n", size); | |
3854 | else | |
3855 | r = sprintf(buf, "%lu (expanded: %lu)\n", size, expanded_size); | |
3856 | mutex_unlock(&trace_types_lock); | |
3857 | ||
3858 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, r); | |
3859 | } | |
3860 | ||
4f271a2a VN |
3861 | static ssize_t |
3862 | tracing_free_buffer_write(struct file *filp, const char __user *ubuf, | |
3863 | size_t cnt, loff_t *ppos) | |
3864 | { | |
3865 | /* | |
3866 | * There is no need to read what the user has written, this function | |
3867 | * is just to make sure that there is no error when "echo" is used | |
3868 | */ | |
3869 | ||
3870 | *ppos += cnt; | |
a98a3c3f SR |
3871 | |
3872 | return cnt; | |
3873 | } | |
3874 | ||
4f271a2a VN |
3875 | static int |
3876 | tracing_free_buffer_release(struct inode *inode, struct file *filp) | |
3877 | { | |
cf30cf67 SR |
3878 | /* disable tracing ? */ |
3879 | if (trace_flags & TRACE_ITER_STOP_ON_FREE) | |
3880 | tracing_off(); | |
4f271a2a | 3881 | /* resize the ring buffer to 0 */ |
438ced17 | 3882 | tracing_resize_ring_buffer(0, RING_BUFFER_ALL_CPUS); |
4f271a2a VN |
3883 | |
3884 | return 0; | |
3885 | } | |
3886 | ||
5bf9a1ee PP |
3887 | static ssize_t |
3888 | tracing_mark_write(struct file *filp, const char __user *ubuf, | |
3889 | size_t cnt, loff_t *fpos) | |
3890 | { | |
d696b58c SR |
3891 | unsigned long addr = (unsigned long)ubuf; |
3892 | struct ring_buffer_event *event; | |
3893 | struct ring_buffer *buffer; | |
3894 | struct print_entry *entry; | |
3895 | unsigned long irq_flags; | |
3896 | struct page *pages[2]; | |
6edb2a8a | 3897 | void *map_page[2]; |
d696b58c SR |
3898 | int nr_pages = 1; |
3899 | ssize_t written; | |
d696b58c SR |
3900 | int offset; |
3901 | int size; | |
3902 | int len; | |
3903 | int ret; | |
6edb2a8a | 3904 | int i; |
5bf9a1ee | 3905 | |
c76f0694 | 3906 | if (tracing_disabled) |
5bf9a1ee PP |
3907 | return -EINVAL; |
3908 | ||
5224c3a3 MSB |
3909 | if (!(trace_flags & TRACE_ITER_MARKERS)) |
3910 | return -EINVAL; | |
3911 | ||
5bf9a1ee PP |
3912 | if (cnt > TRACE_BUF_SIZE) |
3913 | cnt = TRACE_BUF_SIZE; | |
3914 | ||
d696b58c SR |
3915 | /* |
3916 | * Userspace is injecting traces into the kernel trace buffer. | |
3917 | * We want to be as non intrusive as possible. | |
3918 | * To do so, we do not want to allocate any special buffers | |
3919 | * or take any locks, but instead write the userspace data | |
3920 | * straight into the ring buffer. | |
3921 | * | |
3922 | * First we need to pin the userspace buffer into memory, | |
3923 | * which, most likely it is, because it just referenced it. | |
3924 | * But there's no guarantee that it is. By using get_user_pages_fast() | |
3925 | * and kmap_atomic/kunmap_atomic() we can get access to the | |
3926 | * pages directly. We then write the data directly into the | |
3927 | * ring buffer. | |
3928 | */ | |
3929 | BUILD_BUG_ON(TRACE_BUF_SIZE >= PAGE_SIZE); | |
5bf9a1ee | 3930 | |
d696b58c SR |
3931 | /* check if we cross pages */ |
3932 | if ((addr & PAGE_MASK) != ((addr + cnt) & PAGE_MASK)) | |
3933 | nr_pages = 2; | |
3934 | ||
3935 | offset = addr & (PAGE_SIZE - 1); | |
3936 | addr &= PAGE_MASK; | |
3937 | ||
3938 | ret = get_user_pages_fast(addr, nr_pages, 0, pages); | |
3939 | if (ret < nr_pages) { | |
3940 | while (--ret >= 0) | |
3941 | put_page(pages[ret]); | |
3942 | written = -EFAULT; | |
3943 | goto out; | |
5bf9a1ee | 3944 | } |
d696b58c | 3945 | |
6edb2a8a SR |
3946 | for (i = 0; i < nr_pages; i++) |
3947 | map_page[i] = kmap_atomic(pages[i]); | |
d696b58c SR |
3948 | |
3949 | local_save_flags(irq_flags); | |
3950 | size = sizeof(*entry) + cnt + 2; /* possible \n added */ | |
3951 | buffer = global_trace.buffer; | |
3952 | event = trace_buffer_lock_reserve(buffer, TRACE_PRINT, size, | |
3953 | irq_flags, preempt_count()); | |
3954 | if (!event) { | |
3955 | /* Ring buffer disabled, return as if not open for write */ | |
3956 | written = -EBADF; | |
3957 | goto out_unlock; | |
5bf9a1ee | 3958 | } |
d696b58c SR |
3959 | |
3960 | entry = ring_buffer_event_data(event); | |
3961 | entry->ip = _THIS_IP_; | |
3962 | ||
3963 | if (nr_pages == 2) { | |
3964 | len = PAGE_SIZE - offset; | |
6edb2a8a SR |
3965 | memcpy(&entry->buf, map_page[0] + offset, len); |
3966 | memcpy(&entry->buf[len], map_page[1], cnt - len); | |
c13d2f7c | 3967 | } else |
6edb2a8a | 3968 | memcpy(&entry->buf, map_page[0] + offset, cnt); |
5bf9a1ee | 3969 | |
d696b58c SR |
3970 | if (entry->buf[cnt - 1] != '\n') { |
3971 | entry->buf[cnt] = '\n'; | |
3972 | entry->buf[cnt + 1] = '\0'; | |
3973 | } else | |
3974 | entry->buf[cnt] = '\0'; | |
3975 | ||
7ffbd48d | 3976 | __buffer_unlock_commit(buffer, event); |
5bf9a1ee | 3977 | |
d696b58c | 3978 | written = cnt; |
5bf9a1ee | 3979 | |
d696b58c | 3980 | *fpos += written; |
1aa54bca | 3981 | |
d696b58c | 3982 | out_unlock: |
6edb2a8a SR |
3983 | for (i = 0; i < nr_pages; i++){ |
3984 | kunmap_atomic(map_page[i]); | |
3985 | put_page(pages[i]); | |
3986 | } | |
d696b58c | 3987 | out: |
1aa54bca | 3988 | return written; |
5bf9a1ee PP |
3989 | } |
3990 | ||
13f16d20 | 3991 | static int tracing_clock_show(struct seq_file *m, void *v) |
5079f326 | 3992 | { |
5079f326 Z |
3993 | int i; |
3994 | ||
3995 | for (i = 0; i < ARRAY_SIZE(trace_clocks); i++) | |
13f16d20 | 3996 | seq_printf(m, |
5079f326 Z |
3997 | "%s%s%s%s", i ? " " : "", |
3998 | i == trace_clock_id ? "[" : "", trace_clocks[i].name, | |
3999 | i == trace_clock_id ? "]" : ""); | |
13f16d20 | 4000 | seq_putc(m, '\n'); |
5079f326 | 4001 | |
13f16d20 | 4002 | return 0; |
5079f326 Z |
4003 | } |
4004 | ||
4005 | static ssize_t tracing_clock_write(struct file *filp, const char __user *ubuf, | |
4006 | size_t cnt, loff_t *fpos) | |
4007 | { | |
4008 | char buf[64]; | |
4009 | const char *clockstr; | |
4010 | int i; | |
4011 | ||
4012 | if (cnt >= sizeof(buf)) | |
4013 | return -EINVAL; | |
4014 | ||
4015 | if (copy_from_user(&buf, ubuf, cnt)) | |
4016 | return -EFAULT; | |
4017 | ||
4018 | buf[cnt] = 0; | |
4019 | ||
4020 | clockstr = strstrip(buf); | |
4021 | ||
4022 | for (i = 0; i < ARRAY_SIZE(trace_clocks); i++) { | |
4023 | if (strcmp(trace_clocks[i].name, clockstr) == 0) | |
4024 | break; | |
4025 | } | |
4026 | if (i == ARRAY_SIZE(trace_clocks)) | |
4027 | return -EINVAL; | |
4028 | ||
4029 | trace_clock_id = i; | |
4030 | ||
4031 | mutex_lock(&trace_types_lock); | |
4032 | ||
4033 | ring_buffer_set_clock(global_trace.buffer, trace_clocks[i].func); | |
4034 | if (max_tr.buffer) | |
4035 | ring_buffer_set_clock(max_tr.buffer, trace_clocks[i].func); | |
4036 | ||
60303ed3 DS |
4037 | /* |
4038 | * New clock may not be consistent with the previous clock. | |
4039 | * Reset the buffer so that it doesn't have incomparable timestamps. | |
4040 | */ | |
4041 | tracing_reset_online_cpus(&global_trace); | |
84c6cf0d | 4042 | tracing_reset_online_cpus(&max_tr); |
60303ed3 | 4043 | |
5079f326 Z |
4044 | mutex_unlock(&trace_types_lock); |
4045 | ||
4046 | *fpos += cnt; | |
4047 | ||
4048 | return cnt; | |
4049 | } | |
4050 | ||
13f16d20 LZ |
4051 | static int tracing_clock_open(struct inode *inode, struct file *file) |
4052 | { | |
4053 | if (tracing_disabled) | |
4054 | return -ENODEV; | |
4055 | return single_open(file, tracing_clock_show, NULL); | |
4056 | } | |
4057 | ||
5e2336a0 | 4058 | static const struct file_operations tracing_max_lat_fops = { |
4bf39a94 IM |
4059 | .open = tracing_open_generic, |
4060 | .read = tracing_max_lat_read, | |
4061 | .write = tracing_max_lat_write, | |
b444786f | 4062 | .llseek = generic_file_llseek, |
bc0c38d1 SR |
4063 | }; |
4064 | ||
5e2336a0 | 4065 | static const struct file_operations set_tracer_fops = { |
4bf39a94 IM |
4066 | .open = tracing_open_generic, |
4067 | .read = tracing_set_trace_read, | |
4068 | .write = tracing_set_trace_write, | |
b444786f | 4069 | .llseek = generic_file_llseek, |
bc0c38d1 SR |
4070 | }; |
4071 | ||
5e2336a0 | 4072 | static const struct file_operations tracing_pipe_fops = { |
4bf39a94 | 4073 | .open = tracing_open_pipe, |
2a2cc8f7 | 4074 | .poll = tracing_poll_pipe, |
4bf39a94 | 4075 | .read = tracing_read_pipe, |
3c56819b | 4076 | .splice_read = tracing_splice_read_pipe, |
4bf39a94 | 4077 | .release = tracing_release_pipe, |
b444786f | 4078 | .llseek = no_llseek, |
b3806b43 SR |
4079 | }; |
4080 | ||
5e2336a0 | 4081 | static const struct file_operations tracing_entries_fops = { |
438ced17 | 4082 | .open = tracing_entries_open, |
a98a3c3f SR |
4083 | .read = tracing_entries_read, |
4084 | .write = tracing_entries_write, | |
438ced17 | 4085 | .release = tracing_entries_release, |
b444786f | 4086 | .llseek = generic_file_llseek, |
a98a3c3f SR |
4087 | }; |
4088 | ||
f81ab074 VN |
4089 | static const struct file_operations tracing_total_entries_fops = { |
4090 | .open = tracing_open_generic, | |
4091 | .read = tracing_total_entries_read, | |
4092 | .llseek = generic_file_llseek, | |
4093 | }; | |
4094 | ||
4f271a2a VN |
4095 | static const struct file_operations tracing_free_buffer_fops = { |
4096 | .write = tracing_free_buffer_write, | |
4097 | .release = tracing_free_buffer_release, | |
4098 | }; | |
4099 | ||
5e2336a0 | 4100 | static const struct file_operations tracing_mark_fops = { |
43a15386 | 4101 | .open = tracing_open_generic, |
5bf9a1ee | 4102 | .write = tracing_mark_write, |
b444786f | 4103 | .llseek = generic_file_llseek, |
5bf9a1ee PP |
4104 | }; |
4105 | ||
5079f326 | 4106 | static const struct file_operations trace_clock_fops = { |
13f16d20 LZ |
4107 | .open = tracing_clock_open, |
4108 | .read = seq_read, | |
4109 | .llseek = seq_lseek, | |
4110 | .release = single_release, | |
5079f326 Z |
4111 | .write = tracing_clock_write, |
4112 | }; | |
4113 | ||
2cadf913 SR |
4114 | struct ftrace_buffer_info { |
4115 | struct trace_array *tr; | |
4116 | void *spare; | |
4117 | int cpu; | |
4118 | unsigned int read; | |
4119 | }; | |
4120 | ||
4121 | static int tracing_buffers_open(struct inode *inode, struct file *filp) | |
4122 | { | |
4123 | int cpu = (int)(long)inode->i_private; | |
4124 | struct ftrace_buffer_info *info; | |
4125 | ||
4126 | if (tracing_disabled) | |
4127 | return -ENODEV; | |
4128 | ||
4129 | info = kzalloc(sizeof(*info), GFP_KERNEL); | |
4130 | if (!info) | |
4131 | return -ENOMEM; | |
4132 | ||
4133 | info->tr = &global_trace; | |
4134 | info->cpu = cpu; | |
ddd538f3 | 4135 | info->spare = NULL; |
2cadf913 SR |
4136 | /* Force reading ring buffer for first read */ |
4137 | info->read = (unsigned int)-1; | |
2cadf913 SR |
4138 | |
4139 | filp->private_data = info; | |
4140 | ||
d1e7e02f | 4141 | return nonseekable_open(inode, filp); |
2cadf913 SR |
4142 | } |
4143 | ||
4144 | static ssize_t | |
4145 | tracing_buffers_read(struct file *filp, char __user *ubuf, | |
4146 | size_t count, loff_t *ppos) | |
4147 | { | |
4148 | struct ftrace_buffer_info *info = filp->private_data; | |
2cadf913 SR |
4149 | ssize_t ret; |
4150 | size_t size; | |
4151 | ||
2dc5d12b SR |
4152 | if (!count) |
4153 | return 0; | |
4154 | ||
ddd538f3 | 4155 | if (!info->spare) |
7ea59064 | 4156 | info->spare = ring_buffer_alloc_read_page(info->tr->buffer, info->cpu); |
ddd538f3 LJ |
4157 | if (!info->spare) |
4158 | return -ENOMEM; | |
4159 | ||
2cadf913 SR |
4160 | /* Do we have previous read data to read? */ |
4161 | if (info->read < PAGE_SIZE) | |
4162 | goto read; | |
4163 | ||
7e53bd42 | 4164 | trace_access_lock(info->cpu); |
2cadf913 SR |
4165 | ret = ring_buffer_read_page(info->tr->buffer, |
4166 | &info->spare, | |
4167 | count, | |
4168 | info->cpu, 0); | |
7e53bd42 | 4169 | trace_access_unlock(info->cpu); |
2cadf913 SR |
4170 | if (ret < 0) |
4171 | return 0; | |
4172 | ||
436fc280 SR |
4173 | info->read = 0; |
4174 | ||
2cadf913 SR |
4175 | read: |
4176 | size = PAGE_SIZE - info->read; | |
4177 | if (size > count) | |
4178 | size = count; | |
4179 | ||
4180 | ret = copy_to_user(ubuf, info->spare + info->read, size); | |
2dc5d12b | 4181 | if (ret == size) |
2cadf913 | 4182 | return -EFAULT; |
2dc5d12b SR |
4183 | size -= ret; |
4184 | ||
2cadf913 SR |
4185 | *ppos += size; |
4186 | info->read += size; | |
4187 | ||
4188 | return size; | |
4189 | } | |
4190 | ||
4191 | static int tracing_buffers_release(struct inode *inode, struct file *file) | |
4192 | { | |
4193 | struct ftrace_buffer_info *info = file->private_data; | |
4194 | ||
ddd538f3 LJ |
4195 | if (info->spare) |
4196 | ring_buffer_free_read_page(info->tr->buffer, info->spare); | |
2cadf913 SR |
4197 | kfree(info); |
4198 | ||
4199 | return 0; | |
4200 | } | |
4201 | ||
4202 | struct buffer_ref { | |
4203 | struct ring_buffer *buffer; | |
4204 | void *page; | |
4205 | int ref; | |
4206 | }; | |
4207 | ||
4208 | static void buffer_pipe_buf_release(struct pipe_inode_info *pipe, | |
4209 | struct pipe_buffer *buf) | |
4210 | { | |
4211 | struct buffer_ref *ref = (struct buffer_ref *)buf->private; | |
4212 | ||
4213 | if (--ref->ref) | |
4214 | return; | |
4215 | ||
4216 | ring_buffer_free_read_page(ref->buffer, ref->page); | |
4217 | kfree(ref); | |
4218 | buf->private = 0; | |
4219 | } | |
4220 | ||
2cadf913 SR |
4221 | static void buffer_pipe_buf_get(struct pipe_inode_info *pipe, |
4222 | struct pipe_buffer *buf) | |
4223 | { | |
4224 | struct buffer_ref *ref = (struct buffer_ref *)buf->private; | |
4225 | ||
4226 | ref->ref++; | |
4227 | } | |
4228 | ||
4229 | /* Pipe buffer operations for a buffer. */ | |
28dfef8f | 4230 | static const struct pipe_buf_operations buffer_pipe_buf_ops = { |
2cadf913 SR |
4231 | .can_merge = 0, |
4232 | .map = generic_pipe_buf_map, | |
4233 | .unmap = generic_pipe_buf_unmap, | |
4234 | .confirm = generic_pipe_buf_confirm, | |
4235 | .release = buffer_pipe_buf_release, | |
d55cb6cf | 4236 | .steal = generic_pipe_buf_steal, |
2cadf913 SR |
4237 | .get = buffer_pipe_buf_get, |
4238 | }; | |
4239 | ||
4240 | /* | |
4241 | * Callback from splice_to_pipe(), if we need to release some pages | |
4242 | * at the end of the spd in case we error'ed out in filling the pipe. | |
4243 | */ | |
4244 | static void buffer_spd_release(struct splice_pipe_desc *spd, unsigned int i) | |
4245 | { | |
4246 | struct buffer_ref *ref = | |
4247 | (struct buffer_ref *)spd->partial[i].private; | |
4248 | ||
4249 | if (--ref->ref) | |
4250 | return; | |
4251 | ||
4252 | ring_buffer_free_read_page(ref->buffer, ref->page); | |
4253 | kfree(ref); | |
4254 | spd->partial[i].private = 0; | |
4255 | } | |
4256 | ||
4257 | static ssize_t | |
4258 | tracing_buffers_splice_read(struct file *file, loff_t *ppos, | |
4259 | struct pipe_inode_info *pipe, size_t len, | |
4260 | unsigned int flags) | |
4261 | { | |
4262 | struct ftrace_buffer_info *info = file->private_data; | |
35f3d14d JA |
4263 | struct partial_page partial_def[PIPE_DEF_BUFFERS]; |
4264 | struct page *pages_def[PIPE_DEF_BUFFERS]; | |
2cadf913 | 4265 | struct splice_pipe_desc spd = { |
35f3d14d JA |
4266 | .pages = pages_def, |
4267 | .partial = partial_def, | |
047fe360 | 4268 | .nr_pages_max = PIPE_DEF_BUFFERS, |
2cadf913 SR |
4269 | .flags = flags, |
4270 | .ops = &buffer_pipe_buf_ops, | |
4271 | .spd_release = buffer_spd_release, | |
4272 | }; | |
4273 | struct buffer_ref *ref; | |
93459c6c | 4274 | int entries, size, i; |
2cadf913 SR |
4275 | size_t ret; |
4276 | ||
35f3d14d JA |
4277 | if (splice_grow_spd(pipe, &spd)) |
4278 | return -ENOMEM; | |
4279 | ||
93cfb3c9 | 4280 | if (*ppos & (PAGE_SIZE - 1)) { |
35f3d14d JA |
4281 | ret = -EINVAL; |
4282 | goto out; | |
93cfb3c9 LJ |
4283 | } |
4284 | ||
4285 | if (len & (PAGE_SIZE - 1)) { | |
35f3d14d JA |
4286 | if (len < PAGE_SIZE) { |
4287 | ret = -EINVAL; | |
4288 | goto out; | |
4289 | } | |
93cfb3c9 LJ |
4290 | len &= PAGE_MASK; |
4291 | } | |
4292 | ||
7e53bd42 | 4293 | trace_access_lock(info->cpu); |
93459c6c SR |
4294 | entries = ring_buffer_entries_cpu(info->tr->buffer, info->cpu); |
4295 | ||
35f3d14d | 4296 | for (i = 0; i < pipe->buffers && len && entries; i++, len -= PAGE_SIZE) { |
2cadf913 SR |
4297 | struct page *page; |
4298 | int r; | |
4299 | ||
4300 | ref = kzalloc(sizeof(*ref), GFP_KERNEL); | |
4301 | if (!ref) | |
4302 | break; | |
4303 | ||
7267fa68 | 4304 | ref->ref = 1; |
2cadf913 | 4305 | ref->buffer = info->tr->buffer; |
7ea59064 | 4306 | ref->page = ring_buffer_alloc_read_page(ref->buffer, info->cpu); |
2cadf913 SR |
4307 | if (!ref->page) { |
4308 | kfree(ref); | |
4309 | break; | |
4310 | } | |
4311 | ||
4312 | r = ring_buffer_read_page(ref->buffer, &ref->page, | |
f2957f1f | 4313 | len, info->cpu, 1); |
2cadf913 | 4314 | if (r < 0) { |
7ea59064 | 4315 | ring_buffer_free_read_page(ref->buffer, ref->page); |
2cadf913 SR |
4316 | kfree(ref); |
4317 | break; | |
4318 | } | |
4319 | ||
4320 | /* | |
4321 | * zero out any left over data, this is going to | |
4322 | * user land. | |
4323 | */ | |
4324 | size = ring_buffer_page_len(ref->page); | |
4325 | if (size < PAGE_SIZE) | |
4326 | memset(ref->page + size, 0, PAGE_SIZE - size); | |
4327 | ||
4328 | page = virt_to_page(ref->page); | |
4329 | ||
4330 | spd.pages[i] = page; | |
4331 | spd.partial[i].len = PAGE_SIZE; | |
4332 | spd.partial[i].offset = 0; | |
4333 | spd.partial[i].private = (unsigned long)ref; | |
4334 | spd.nr_pages++; | |
93cfb3c9 | 4335 | *ppos += PAGE_SIZE; |
93459c6c SR |
4336 | |
4337 | entries = ring_buffer_entries_cpu(info->tr->buffer, info->cpu); | |
2cadf913 SR |
4338 | } |
4339 | ||
7e53bd42 | 4340 | trace_access_unlock(info->cpu); |
2cadf913 SR |
4341 | spd.nr_pages = i; |
4342 | ||
4343 | /* did we read anything? */ | |
4344 | if (!spd.nr_pages) { | |
4345 | if (flags & SPLICE_F_NONBLOCK) | |
4346 | ret = -EAGAIN; | |
4347 | else | |
4348 | ret = 0; | |
4349 | /* TODO: block */ | |
35f3d14d | 4350 | goto out; |
2cadf913 SR |
4351 | } |
4352 | ||
4353 | ret = splice_to_pipe(pipe, &spd); | |
047fe360 | 4354 | splice_shrink_spd(&spd); |
35f3d14d | 4355 | out: |
2cadf913 SR |
4356 | return ret; |
4357 | } | |
4358 | ||
4359 | static const struct file_operations tracing_buffers_fops = { | |
4360 | .open = tracing_buffers_open, | |
4361 | .read = tracing_buffers_read, | |
4362 | .release = tracing_buffers_release, | |
4363 | .splice_read = tracing_buffers_splice_read, | |
4364 | .llseek = no_llseek, | |
4365 | }; | |
4366 | ||
c8d77183 SR |
4367 | static ssize_t |
4368 | tracing_stats_read(struct file *filp, char __user *ubuf, | |
4369 | size_t count, loff_t *ppos) | |
4370 | { | |
4371 | unsigned long cpu = (unsigned long)filp->private_data; | |
4372 | struct trace_array *tr = &global_trace; | |
4373 | struct trace_seq *s; | |
4374 | unsigned long cnt; | |
c64e148a VN |
4375 | unsigned long long t; |
4376 | unsigned long usec_rem; | |
c8d77183 | 4377 | |
e4f2d10f | 4378 | s = kmalloc(sizeof(*s), GFP_KERNEL); |
c8d77183 | 4379 | if (!s) |
a646365c | 4380 | return -ENOMEM; |
c8d77183 SR |
4381 | |
4382 | trace_seq_init(s); | |
4383 | ||
4384 | cnt = ring_buffer_entries_cpu(tr->buffer, cpu); | |
4385 | trace_seq_printf(s, "entries: %ld\n", cnt); | |
4386 | ||
4387 | cnt = ring_buffer_overrun_cpu(tr->buffer, cpu); | |
4388 | trace_seq_printf(s, "overrun: %ld\n", cnt); | |
4389 | ||
4390 | cnt = ring_buffer_commit_overrun_cpu(tr->buffer, cpu); | |
4391 | trace_seq_printf(s, "commit overrun: %ld\n", cnt); | |
4392 | ||
c64e148a VN |
4393 | cnt = ring_buffer_bytes_cpu(tr->buffer, cpu); |
4394 | trace_seq_printf(s, "bytes: %ld\n", cnt); | |
4395 | ||
11043d8b YY |
4396 | if (trace_clocks[trace_clock_id].in_ns) { |
4397 | /* local or global for trace_clock */ | |
4398 | t = ns2usecs(ring_buffer_oldest_event_ts(tr->buffer, cpu)); | |
4399 | usec_rem = do_div(t, USEC_PER_SEC); | |
4400 | trace_seq_printf(s, "oldest event ts: %5llu.%06lu\n", | |
4401 | t, usec_rem); | |
4402 | ||
4403 | t = ns2usecs(ring_buffer_time_stamp(tr->buffer, cpu)); | |
4404 | usec_rem = do_div(t, USEC_PER_SEC); | |
4405 | trace_seq_printf(s, "now ts: %5llu.%06lu\n", t, usec_rem); | |
4406 | } else { | |
4407 | /* counter or tsc mode for trace_clock */ | |
4408 | trace_seq_printf(s, "oldest event ts: %llu\n", | |
4409 | ring_buffer_oldest_event_ts(tr->buffer, cpu)); | |
c64e148a | 4410 | |
11043d8b YY |
4411 | trace_seq_printf(s, "now ts: %llu\n", |
4412 | ring_buffer_time_stamp(tr->buffer, cpu)); | |
4413 | } | |
c64e148a | 4414 | |
884bfe89 SP |
4415 | cnt = ring_buffer_dropped_events_cpu(tr->buffer, cpu); |
4416 | trace_seq_printf(s, "dropped events: %ld\n", cnt); | |
4417 | ||
c8d77183 SR |
4418 | count = simple_read_from_buffer(ubuf, count, ppos, s->buffer, s->len); |
4419 | ||
4420 | kfree(s); | |
4421 | ||
4422 | return count; | |
4423 | } | |
4424 | ||
4425 | static const struct file_operations tracing_stats_fops = { | |
4426 | .open = tracing_open_generic, | |
4427 | .read = tracing_stats_read, | |
b444786f | 4428 | .llseek = generic_file_llseek, |
c8d77183 SR |
4429 | }; |
4430 | ||
bc0c38d1 SR |
4431 | #ifdef CONFIG_DYNAMIC_FTRACE |
4432 | ||
b807c3d0 SR |
4433 | int __weak ftrace_arch_read_dyn_info(char *buf, int size) |
4434 | { | |
4435 | return 0; | |
4436 | } | |
4437 | ||
bc0c38d1 | 4438 | static ssize_t |
b807c3d0 | 4439 | tracing_read_dyn_info(struct file *filp, char __user *ubuf, |
bc0c38d1 SR |
4440 | size_t cnt, loff_t *ppos) |
4441 | { | |
a26a2a27 SR |
4442 | static char ftrace_dyn_info_buffer[1024]; |
4443 | static DEFINE_MUTEX(dyn_info_mutex); | |
bc0c38d1 | 4444 | unsigned long *p = filp->private_data; |
b807c3d0 | 4445 | char *buf = ftrace_dyn_info_buffer; |
a26a2a27 | 4446 | int size = ARRAY_SIZE(ftrace_dyn_info_buffer); |
bc0c38d1 SR |
4447 | int r; |
4448 | ||
b807c3d0 SR |
4449 | mutex_lock(&dyn_info_mutex); |
4450 | r = sprintf(buf, "%ld ", *p); | |
4bf39a94 | 4451 | |
a26a2a27 | 4452 | r += ftrace_arch_read_dyn_info(buf+r, (size-1)-r); |
b807c3d0 SR |
4453 | buf[r++] = '\n'; |
4454 | ||
4455 | r = simple_read_from_buffer(ubuf, cnt, ppos, buf, r); | |
4456 | ||
4457 | mutex_unlock(&dyn_info_mutex); | |
4458 | ||
4459 | return r; | |
bc0c38d1 SR |
4460 | } |
4461 | ||
5e2336a0 | 4462 | static const struct file_operations tracing_dyn_info_fops = { |
4bf39a94 | 4463 | .open = tracing_open_generic, |
b807c3d0 | 4464 | .read = tracing_read_dyn_info, |
b444786f | 4465 | .llseek = generic_file_llseek, |
bc0c38d1 SR |
4466 | }; |
4467 | #endif | |
4468 | ||
4469 | static struct dentry *d_tracer; | |
4470 | ||
4471 | struct dentry *tracing_init_dentry(void) | |
4472 | { | |
4473 | static int once; | |
4474 | ||
4475 | if (d_tracer) | |
4476 | return d_tracer; | |
4477 | ||
3e1f60b8 FW |
4478 | if (!debugfs_initialized()) |
4479 | return NULL; | |
4480 | ||
bc0c38d1 SR |
4481 | d_tracer = debugfs_create_dir("tracing", NULL); |
4482 | ||
4483 | if (!d_tracer && !once) { | |
4484 | once = 1; | |
4485 | pr_warning("Could not create debugfs directory 'tracing'\n"); | |
4486 | return NULL; | |
4487 | } | |
4488 | ||
4489 | return d_tracer; | |
4490 | } | |
4491 | ||
b04cc6b1 FW |
4492 | static struct dentry *d_percpu; |
4493 | ||
4494 | struct dentry *tracing_dentry_percpu(void) | |
4495 | { | |
4496 | static int once; | |
4497 | struct dentry *d_tracer; | |
4498 | ||
4499 | if (d_percpu) | |
4500 | return d_percpu; | |
4501 | ||
4502 | d_tracer = tracing_init_dentry(); | |
4503 | ||
4504 | if (!d_tracer) | |
4505 | return NULL; | |
4506 | ||
4507 | d_percpu = debugfs_create_dir("per_cpu", d_tracer); | |
4508 | ||
4509 | if (!d_percpu && !once) { | |
4510 | once = 1; | |
4511 | pr_warning("Could not create debugfs directory 'per_cpu'\n"); | |
4512 | return NULL; | |
4513 | } | |
4514 | ||
4515 | return d_percpu; | |
4516 | } | |
4517 | ||
4518 | static void tracing_init_debugfs_percpu(long cpu) | |
4519 | { | |
4520 | struct dentry *d_percpu = tracing_dentry_percpu(); | |
5452af66 | 4521 | struct dentry *d_cpu; |
dd49a38c | 4522 | char cpu_dir[30]; /* 30 characters should be more than enough */ |
b04cc6b1 | 4523 | |
0a3d7ce7 NK |
4524 | if (!d_percpu) |
4525 | return; | |
4526 | ||
dd49a38c | 4527 | snprintf(cpu_dir, 30, "cpu%ld", cpu); |
8656e7a2 FW |
4528 | d_cpu = debugfs_create_dir(cpu_dir, d_percpu); |
4529 | if (!d_cpu) { | |
4530 | pr_warning("Could not create debugfs '%s' entry\n", cpu_dir); | |
4531 | return; | |
4532 | } | |
b04cc6b1 | 4533 | |
8656e7a2 | 4534 | /* per cpu trace_pipe */ |
5452af66 FW |
4535 | trace_create_file("trace_pipe", 0444, d_cpu, |
4536 | (void *) cpu, &tracing_pipe_fops); | |
b04cc6b1 FW |
4537 | |
4538 | /* per cpu trace */ | |
5452af66 FW |
4539 | trace_create_file("trace", 0644, d_cpu, |
4540 | (void *) cpu, &tracing_fops); | |
7f96f93f | 4541 | |
5452af66 FW |
4542 | trace_create_file("trace_pipe_raw", 0444, d_cpu, |
4543 | (void *) cpu, &tracing_buffers_fops); | |
7f96f93f | 4544 | |
c8d77183 SR |
4545 | trace_create_file("stats", 0444, d_cpu, |
4546 | (void *) cpu, &tracing_stats_fops); | |
438ced17 VN |
4547 | |
4548 | trace_create_file("buffer_size_kb", 0444, d_cpu, | |
4549 | (void *) cpu, &tracing_entries_fops); | |
b04cc6b1 FW |
4550 | } |
4551 | ||
60a11774 SR |
4552 | #ifdef CONFIG_FTRACE_SELFTEST |
4553 | /* Let selftest have access to static functions in this file */ | |
4554 | #include "trace_selftest.c" | |
4555 | #endif | |
4556 | ||
577b785f SR |
4557 | struct trace_option_dentry { |
4558 | struct tracer_opt *opt; | |
4559 | struct tracer_flags *flags; | |
4560 | struct dentry *entry; | |
4561 | }; | |
4562 | ||
4563 | static ssize_t | |
4564 | trace_options_read(struct file *filp, char __user *ubuf, size_t cnt, | |
4565 | loff_t *ppos) | |
4566 | { | |
4567 | struct trace_option_dentry *topt = filp->private_data; | |
4568 | char *buf; | |
4569 | ||
4570 | if (topt->flags->val & topt->opt->bit) | |
4571 | buf = "1\n"; | |
4572 | else | |
4573 | buf = "0\n"; | |
4574 | ||
4575 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, 2); | |
4576 | } | |
4577 | ||
4578 | static ssize_t | |
4579 | trace_options_write(struct file *filp, const char __user *ubuf, size_t cnt, | |
4580 | loff_t *ppos) | |
4581 | { | |
4582 | struct trace_option_dentry *topt = filp->private_data; | |
4583 | unsigned long val; | |
577b785f SR |
4584 | int ret; |
4585 | ||
22fe9b54 PH |
4586 | ret = kstrtoul_from_user(ubuf, cnt, 10, &val); |
4587 | if (ret) | |
577b785f SR |
4588 | return ret; |
4589 | ||
8d18eaaf LZ |
4590 | if (val != 0 && val != 1) |
4591 | return -EINVAL; | |
577b785f | 4592 | |
8d18eaaf | 4593 | if (!!(topt->flags->val & topt->opt->bit) != val) { |
577b785f | 4594 | mutex_lock(&trace_types_lock); |
8d18eaaf | 4595 | ret = __set_tracer_option(current_trace, topt->flags, |
c757bea9 | 4596 | topt->opt, !val); |
577b785f SR |
4597 | mutex_unlock(&trace_types_lock); |
4598 | if (ret) | |
4599 | return ret; | |
577b785f SR |
4600 | } |
4601 | ||
4602 | *ppos += cnt; | |
4603 | ||
4604 | return cnt; | |
4605 | } | |
4606 | ||
4607 | ||
4608 | static const struct file_operations trace_options_fops = { | |
4609 | .open = tracing_open_generic, | |
4610 | .read = trace_options_read, | |
4611 | .write = trace_options_write, | |
b444786f | 4612 | .llseek = generic_file_llseek, |
577b785f SR |
4613 | }; |
4614 | ||
a8259075 SR |
4615 | static ssize_t |
4616 | trace_options_core_read(struct file *filp, char __user *ubuf, size_t cnt, | |
4617 | loff_t *ppos) | |
4618 | { | |
4619 | long index = (long)filp->private_data; | |
4620 | char *buf; | |
4621 | ||
4622 | if (trace_flags & (1 << index)) | |
4623 | buf = "1\n"; | |
4624 | else | |
4625 | buf = "0\n"; | |
4626 | ||
4627 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, 2); | |
4628 | } | |
4629 | ||
4630 | static ssize_t | |
4631 | trace_options_core_write(struct file *filp, const char __user *ubuf, size_t cnt, | |
4632 | loff_t *ppos) | |
4633 | { | |
4634 | long index = (long)filp->private_data; | |
a8259075 SR |
4635 | unsigned long val; |
4636 | int ret; | |
4637 | ||
22fe9b54 PH |
4638 | ret = kstrtoul_from_user(ubuf, cnt, 10, &val); |
4639 | if (ret) | |
a8259075 SR |
4640 | return ret; |
4641 | ||
f2d84b65 | 4642 | if (val != 0 && val != 1) |
a8259075 | 4643 | return -EINVAL; |
f2d84b65 | 4644 | set_tracer_flags(1 << index, val); |
a8259075 SR |
4645 | |
4646 | *ppos += cnt; | |
4647 | ||
4648 | return cnt; | |
4649 | } | |
4650 | ||
a8259075 SR |
4651 | static const struct file_operations trace_options_core_fops = { |
4652 | .open = tracing_open_generic, | |
4653 | .read = trace_options_core_read, | |
4654 | .write = trace_options_core_write, | |
b444786f | 4655 | .llseek = generic_file_llseek, |
a8259075 SR |
4656 | }; |
4657 | ||
5452af66 | 4658 | struct dentry *trace_create_file(const char *name, |
f4ae40a6 | 4659 | umode_t mode, |
5452af66 FW |
4660 | struct dentry *parent, |
4661 | void *data, | |
4662 | const struct file_operations *fops) | |
4663 | { | |
4664 | struct dentry *ret; | |
4665 | ||
4666 | ret = debugfs_create_file(name, mode, parent, data, fops); | |
4667 | if (!ret) | |
4668 | pr_warning("Could not create debugfs '%s' entry\n", name); | |
4669 | ||
4670 | return ret; | |
4671 | } | |
4672 | ||
4673 | ||
a8259075 SR |
4674 | static struct dentry *trace_options_init_dentry(void) |
4675 | { | |
4676 | struct dentry *d_tracer; | |
4677 | static struct dentry *t_options; | |
4678 | ||
4679 | if (t_options) | |
4680 | return t_options; | |
4681 | ||
4682 | d_tracer = tracing_init_dentry(); | |
4683 | if (!d_tracer) | |
4684 | return NULL; | |
4685 | ||
4686 | t_options = debugfs_create_dir("options", d_tracer); | |
4687 | if (!t_options) { | |
4688 | pr_warning("Could not create debugfs directory 'options'\n"); | |
4689 | return NULL; | |
4690 | } | |
4691 | ||
4692 | return t_options; | |
4693 | } | |
4694 | ||
577b785f SR |
4695 | static void |
4696 | create_trace_option_file(struct trace_option_dentry *topt, | |
4697 | struct tracer_flags *flags, | |
4698 | struct tracer_opt *opt) | |
4699 | { | |
4700 | struct dentry *t_options; | |
577b785f SR |
4701 | |
4702 | t_options = trace_options_init_dentry(); | |
4703 | if (!t_options) | |
4704 | return; | |
4705 | ||
4706 | topt->flags = flags; | |
4707 | topt->opt = opt; | |
4708 | ||
5452af66 | 4709 | topt->entry = trace_create_file(opt->name, 0644, t_options, topt, |
577b785f SR |
4710 | &trace_options_fops); |
4711 | ||
577b785f SR |
4712 | } |
4713 | ||
4714 | static struct trace_option_dentry * | |
4715 | create_trace_option_files(struct tracer *tracer) | |
4716 | { | |
4717 | struct trace_option_dentry *topts; | |
4718 | struct tracer_flags *flags; | |
4719 | struct tracer_opt *opts; | |
4720 | int cnt; | |
4721 | ||
4722 | if (!tracer) | |
4723 | return NULL; | |
4724 | ||
4725 | flags = tracer->flags; | |
4726 | ||
4727 | if (!flags || !flags->opts) | |
4728 | return NULL; | |
4729 | ||
4730 | opts = flags->opts; | |
4731 | ||
4732 | for (cnt = 0; opts[cnt].name; cnt++) | |
4733 | ; | |
4734 | ||
0cfe8245 | 4735 | topts = kcalloc(cnt + 1, sizeof(*topts), GFP_KERNEL); |
577b785f SR |
4736 | if (!topts) |
4737 | return NULL; | |
4738 | ||
4739 | for (cnt = 0; opts[cnt].name; cnt++) | |
4740 | create_trace_option_file(&topts[cnt], flags, | |
4741 | &opts[cnt]); | |
4742 | ||
4743 | return topts; | |
4744 | } | |
4745 | ||
4746 | static void | |
4747 | destroy_trace_option_files(struct trace_option_dentry *topts) | |
4748 | { | |
4749 | int cnt; | |
4750 | ||
4751 | if (!topts) | |
4752 | return; | |
4753 | ||
4754 | for (cnt = 0; topts[cnt].opt; cnt++) { | |
4755 | if (topts[cnt].entry) | |
4756 | debugfs_remove(topts[cnt].entry); | |
4757 | } | |
4758 | ||
4759 | kfree(topts); | |
4760 | } | |
4761 | ||
a8259075 SR |
4762 | static struct dentry * |
4763 | create_trace_option_core_file(const char *option, long index) | |
4764 | { | |
4765 | struct dentry *t_options; | |
a8259075 SR |
4766 | |
4767 | t_options = trace_options_init_dentry(); | |
4768 | if (!t_options) | |
4769 | return NULL; | |
4770 | ||
5452af66 | 4771 | return trace_create_file(option, 0644, t_options, (void *)index, |
a8259075 | 4772 | &trace_options_core_fops); |
a8259075 SR |
4773 | } |
4774 | ||
4775 | static __init void create_trace_options_dir(void) | |
4776 | { | |
4777 | struct dentry *t_options; | |
a8259075 SR |
4778 | int i; |
4779 | ||
4780 | t_options = trace_options_init_dentry(); | |
4781 | if (!t_options) | |
4782 | return; | |
4783 | ||
5452af66 FW |
4784 | for (i = 0; trace_options[i]; i++) |
4785 | create_trace_option_core_file(trace_options[i], i); | |
a8259075 SR |
4786 | } |
4787 | ||
499e5470 SR |
4788 | static ssize_t |
4789 | rb_simple_read(struct file *filp, char __user *ubuf, | |
4790 | size_t cnt, loff_t *ppos) | |
4791 | { | |
348f0fc2 SR |
4792 | struct trace_array *tr = filp->private_data; |
4793 | struct ring_buffer *buffer = tr->buffer; | |
499e5470 SR |
4794 | char buf[64]; |
4795 | int r; | |
4796 | ||
4797 | if (buffer) | |
4798 | r = ring_buffer_record_is_on(buffer); | |
4799 | else | |
4800 | r = 0; | |
4801 | ||
4802 | r = sprintf(buf, "%d\n", r); | |
4803 | ||
4804 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, r); | |
4805 | } | |
4806 | ||
4807 | static ssize_t | |
4808 | rb_simple_write(struct file *filp, const char __user *ubuf, | |
4809 | size_t cnt, loff_t *ppos) | |
4810 | { | |
348f0fc2 SR |
4811 | struct trace_array *tr = filp->private_data; |
4812 | struct ring_buffer *buffer = tr->buffer; | |
499e5470 SR |
4813 | unsigned long val; |
4814 | int ret; | |
4815 | ||
4816 | ret = kstrtoul_from_user(ubuf, cnt, 10, &val); | |
4817 | if (ret) | |
4818 | return ret; | |
4819 | ||
4820 | if (buffer) { | |
2df8f8a6 SR |
4821 | mutex_lock(&trace_types_lock); |
4822 | if (val) { | |
499e5470 | 4823 | ring_buffer_record_on(buffer); |
2df8f8a6 SR |
4824 | if (current_trace->start) |
4825 | current_trace->start(tr); | |
4826 | } else { | |
499e5470 | 4827 | ring_buffer_record_off(buffer); |
2df8f8a6 SR |
4828 | if (current_trace->stop) |
4829 | current_trace->stop(tr); | |
4830 | } | |
4831 | mutex_unlock(&trace_types_lock); | |
499e5470 SR |
4832 | } |
4833 | ||
4834 | (*ppos)++; | |
4835 | ||
4836 | return cnt; | |
4837 | } | |
4838 | ||
4839 | static const struct file_operations rb_simple_fops = { | |
4840 | .open = tracing_open_generic, | |
4841 | .read = rb_simple_read, | |
4842 | .write = rb_simple_write, | |
4843 | .llseek = default_llseek, | |
4844 | }; | |
4845 | ||
b5ad384e | 4846 | static __init int tracer_init_debugfs(void) |
bc0c38d1 SR |
4847 | { |
4848 | struct dentry *d_tracer; | |
b04cc6b1 | 4849 | int cpu; |
bc0c38d1 | 4850 | |
7e53bd42 LJ |
4851 | trace_access_lock_init(); |
4852 | ||
bc0c38d1 SR |
4853 | d_tracer = tracing_init_dentry(); |
4854 | ||
5452af66 FW |
4855 | trace_create_file("trace_options", 0644, d_tracer, |
4856 | NULL, &tracing_iter_fops); | |
bc0c38d1 | 4857 | |
5452af66 FW |
4858 | trace_create_file("tracing_cpumask", 0644, d_tracer, |
4859 | NULL, &tracing_cpumask_fops); | |
4860 | ||
4861 | trace_create_file("trace", 0644, d_tracer, | |
4862 | (void *) TRACE_PIPE_ALL_CPU, &tracing_fops); | |
a8259075 | 4863 | |
5452af66 FW |
4864 | trace_create_file("available_tracers", 0444, d_tracer, |
4865 | &global_trace, &show_traces_fops); | |
4866 | ||
339ae5d3 | 4867 | trace_create_file("current_tracer", 0644, d_tracer, |
5452af66 FW |
4868 | &global_trace, &set_tracer_fops); |
4869 | ||
5d4a9dba | 4870 | #ifdef CONFIG_TRACER_MAX_TRACE |
5452af66 FW |
4871 | trace_create_file("tracing_max_latency", 0644, d_tracer, |
4872 | &tracing_max_latency, &tracing_max_lat_fops); | |
0e950173 | 4873 | #endif |
5452af66 FW |
4874 | |
4875 | trace_create_file("tracing_thresh", 0644, d_tracer, | |
4876 | &tracing_thresh, &tracing_max_lat_fops); | |
a8259075 | 4877 | |
339ae5d3 | 4878 | trace_create_file("README", 0444, d_tracer, |
5452af66 FW |
4879 | NULL, &tracing_readme_fops); |
4880 | ||
4881 | trace_create_file("trace_pipe", 0444, d_tracer, | |
b04cc6b1 | 4882 | (void *) TRACE_PIPE_ALL_CPU, &tracing_pipe_fops); |
5452af66 FW |
4883 | |
4884 | trace_create_file("buffer_size_kb", 0644, d_tracer, | |
438ced17 | 4885 | (void *) RING_BUFFER_ALL_CPUS, &tracing_entries_fops); |
5452af66 | 4886 | |
f81ab074 VN |
4887 | trace_create_file("buffer_total_size_kb", 0444, d_tracer, |
4888 | &global_trace, &tracing_total_entries_fops); | |
4889 | ||
4f271a2a VN |
4890 | trace_create_file("free_buffer", 0644, d_tracer, |
4891 | &global_trace, &tracing_free_buffer_fops); | |
4892 | ||
5452af66 FW |
4893 | trace_create_file("trace_marker", 0220, d_tracer, |
4894 | NULL, &tracing_mark_fops); | |
5bf9a1ee | 4895 | |
69abe6a5 AP |
4896 | trace_create_file("saved_cmdlines", 0444, d_tracer, |
4897 | NULL, &tracing_saved_cmdlines_fops); | |
5bf9a1ee | 4898 | |
5079f326 Z |
4899 | trace_create_file("trace_clock", 0644, d_tracer, NULL, |
4900 | &trace_clock_fops); | |
4901 | ||
499e5470 | 4902 | trace_create_file("tracing_on", 0644, d_tracer, |
348f0fc2 | 4903 | &global_trace, &rb_simple_fops); |
499e5470 | 4904 | |
bc0c38d1 | 4905 | #ifdef CONFIG_DYNAMIC_FTRACE |
5452af66 FW |
4906 | trace_create_file("dyn_ftrace_total_info", 0444, d_tracer, |
4907 | &ftrace_update_tot_cnt, &tracing_dyn_info_fops); | |
bc0c38d1 | 4908 | #endif |
b04cc6b1 | 4909 | |
5452af66 FW |
4910 | create_trace_options_dir(); |
4911 | ||
b04cc6b1 FW |
4912 | for_each_tracing_cpu(cpu) |
4913 | tracing_init_debugfs_percpu(cpu); | |
4914 | ||
b5ad384e | 4915 | return 0; |
bc0c38d1 SR |
4916 | } |
4917 | ||
3f5a54e3 SR |
4918 | static int trace_panic_handler(struct notifier_block *this, |
4919 | unsigned long event, void *unused) | |
4920 | { | |
944ac425 | 4921 | if (ftrace_dump_on_oops) |
cecbca96 | 4922 | ftrace_dump(ftrace_dump_on_oops); |
3f5a54e3 SR |
4923 | return NOTIFY_OK; |
4924 | } | |
4925 | ||
4926 | static struct notifier_block trace_panic_notifier = { | |
4927 | .notifier_call = trace_panic_handler, | |
4928 | .next = NULL, | |
4929 | .priority = 150 /* priority: INT_MAX >= x >= 0 */ | |
4930 | }; | |
4931 | ||
4932 | static int trace_die_handler(struct notifier_block *self, | |
4933 | unsigned long val, | |
4934 | void *data) | |
4935 | { | |
4936 | switch (val) { | |
4937 | case DIE_OOPS: | |
944ac425 | 4938 | if (ftrace_dump_on_oops) |
cecbca96 | 4939 | ftrace_dump(ftrace_dump_on_oops); |
3f5a54e3 SR |
4940 | break; |
4941 | default: | |
4942 | break; | |
4943 | } | |
4944 | return NOTIFY_OK; | |
4945 | } | |
4946 | ||
4947 | static struct notifier_block trace_die_notifier = { | |
4948 | .notifier_call = trace_die_handler, | |
4949 | .priority = 200 | |
4950 | }; | |
4951 | ||
4952 | /* | |
4953 | * printk is set to max of 1024, we really don't need it that big. | |
4954 | * Nothing should be printing 1000 characters anyway. | |
4955 | */ | |
4956 | #define TRACE_MAX_PRINT 1000 | |
4957 | ||
4958 | /* | |
4959 | * Define here KERN_TRACE so that we have one place to modify | |
4960 | * it if we decide to change what log level the ftrace dump | |
4961 | * should be at. | |
4962 | */ | |
428aee14 | 4963 | #define KERN_TRACE KERN_EMERG |
3f5a54e3 | 4964 | |
955b61e5 | 4965 | void |
3f5a54e3 SR |
4966 | trace_printk_seq(struct trace_seq *s) |
4967 | { | |
4968 | /* Probably should print a warning here. */ | |
4969 | if (s->len >= 1000) | |
4970 | s->len = 1000; | |
4971 | ||
4972 | /* should be zero ended, but we are paranoid. */ | |
4973 | s->buffer[s->len] = 0; | |
4974 | ||
4975 | printk(KERN_TRACE "%s", s->buffer); | |
4976 | ||
f9520750 | 4977 | trace_seq_init(s); |
3f5a54e3 SR |
4978 | } |
4979 | ||
955b61e5 JW |
4980 | void trace_init_global_iter(struct trace_iterator *iter) |
4981 | { | |
4982 | iter->tr = &global_trace; | |
4983 | iter->trace = current_trace; | |
4984 | iter->cpu_file = TRACE_PIPE_ALL_CPU; | |
4985 | } | |
4986 | ||
cecbca96 FW |
4987 | static void |
4988 | __ftrace_dump(bool disable_tracing, enum ftrace_dump_mode oops_dump_mode) | |
3f5a54e3 | 4989 | { |
445c8951 | 4990 | static arch_spinlock_t ftrace_dump_lock = |
edc35bd7 | 4991 | (arch_spinlock_t)__ARCH_SPIN_LOCK_UNLOCKED; |
3f5a54e3 SR |
4992 | /* use static because iter can be a bit big for the stack */ |
4993 | static struct trace_iterator iter; | |
cf586b61 | 4994 | unsigned int old_userobj; |
3f5a54e3 | 4995 | static int dump_ran; |
d769041f SR |
4996 | unsigned long flags; |
4997 | int cnt = 0, cpu; | |
3f5a54e3 SR |
4998 | |
4999 | /* only one dump */ | |
cd891ae0 | 5000 | local_irq_save(flags); |
0199c4e6 | 5001 | arch_spin_lock(&ftrace_dump_lock); |
3f5a54e3 SR |
5002 | if (dump_ran) |
5003 | goto out; | |
5004 | ||
5005 | dump_ran = 1; | |
5006 | ||
0ee6b6cf | 5007 | tracing_off(); |
cf586b61 | 5008 | |
e0a413f6 SR |
5009 | /* Did function tracer already get disabled? */ |
5010 | if (ftrace_is_dead()) { | |
5011 | printk("# WARNING: FUNCTION TRACING IS CORRUPTED\n"); | |
5012 | printk("# MAY BE MISSING FUNCTION EVENTS\n"); | |
5013 | } | |
5014 | ||
cf586b61 FW |
5015 | if (disable_tracing) |
5016 | ftrace_kill(); | |
3f5a54e3 | 5017 | |
955b61e5 JW |
5018 | trace_init_global_iter(&iter); |
5019 | ||
d769041f | 5020 | for_each_tracing_cpu(cpu) { |
955b61e5 | 5021 | atomic_inc(&iter.tr->data[cpu]->disabled); |
d769041f SR |
5022 | } |
5023 | ||
cf586b61 FW |
5024 | old_userobj = trace_flags & TRACE_ITER_SYM_USEROBJ; |
5025 | ||
b54d3de9 TE |
5026 | /* don't look at user memory in panic mode */ |
5027 | trace_flags &= ~TRACE_ITER_SYM_USEROBJ; | |
5028 | ||
e543ad76 | 5029 | /* Simulate the iterator */ |
3f5a54e3 SR |
5030 | iter.tr = &global_trace; |
5031 | iter.trace = current_trace; | |
cecbca96 FW |
5032 | |
5033 | switch (oops_dump_mode) { | |
5034 | case DUMP_ALL: | |
5035 | iter.cpu_file = TRACE_PIPE_ALL_CPU; | |
5036 | break; | |
5037 | case DUMP_ORIG: | |
5038 | iter.cpu_file = raw_smp_processor_id(); | |
5039 | break; | |
5040 | case DUMP_NONE: | |
5041 | goto out_enable; | |
5042 | default: | |
5043 | printk(KERN_TRACE "Bad dumping mode, switching to all CPUs dump\n"); | |
5044 | iter.cpu_file = TRACE_PIPE_ALL_CPU; | |
5045 | } | |
5046 | ||
5047 | printk(KERN_TRACE "Dumping ftrace buffer:\n"); | |
3f5a54e3 SR |
5048 | |
5049 | /* | |
5050 | * We need to stop all tracing on all CPUS to read the | |
5051 | * the next buffer. This is a bit expensive, but is | |
5052 | * not done often. We fill all what we can read, | |
5053 | * and then release the locks again. | |
5054 | */ | |
5055 | ||
3f5a54e3 SR |
5056 | while (!trace_empty(&iter)) { |
5057 | ||
5058 | if (!cnt) | |
5059 | printk(KERN_TRACE "---------------------------------\n"); | |
5060 | ||
5061 | cnt++; | |
5062 | ||
5063 | /* reset all but tr, trace, and overruns */ | |
5064 | memset(&iter.seq, 0, | |
5065 | sizeof(struct trace_iterator) - | |
5066 | offsetof(struct trace_iterator, seq)); | |
5067 | iter.iter_flags |= TRACE_FILE_LAT_FMT; | |
5068 | iter.pos = -1; | |
5069 | ||
955b61e5 | 5070 | if (trace_find_next_entry_inc(&iter) != NULL) { |
74e7ff8c LJ |
5071 | int ret; |
5072 | ||
5073 | ret = print_trace_line(&iter); | |
5074 | if (ret != TRACE_TYPE_NO_CONSUME) | |
5075 | trace_consume(&iter); | |
3f5a54e3 | 5076 | } |
b892e5c8 | 5077 | touch_nmi_watchdog(); |
3f5a54e3 SR |
5078 | |
5079 | trace_printk_seq(&iter.seq); | |
5080 | } | |
5081 | ||
5082 | if (!cnt) | |
5083 | printk(KERN_TRACE " (ftrace buffer empty)\n"); | |
5084 | else | |
5085 | printk(KERN_TRACE "---------------------------------\n"); | |
5086 | ||
cecbca96 | 5087 | out_enable: |
cf586b61 FW |
5088 | /* Re-enable tracing if requested */ |
5089 | if (!disable_tracing) { | |
5090 | trace_flags |= old_userobj; | |
5091 | ||
5092 | for_each_tracing_cpu(cpu) { | |
955b61e5 | 5093 | atomic_dec(&iter.tr->data[cpu]->disabled); |
cf586b61 FW |
5094 | } |
5095 | tracing_on(); | |
5096 | } | |
5097 | ||
3f5a54e3 | 5098 | out: |
0199c4e6 | 5099 | arch_spin_unlock(&ftrace_dump_lock); |
cd891ae0 | 5100 | local_irq_restore(flags); |
3f5a54e3 SR |
5101 | } |
5102 | ||
cf586b61 | 5103 | /* By default: disable tracing after the dump */ |
cecbca96 | 5104 | void ftrace_dump(enum ftrace_dump_mode oops_dump_mode) |
cf586b61 | 5105 | { |
cecbca96 | 5106 | __ftrace_dump(true, oops_dump_mode); |
cf586b61 | 5107 | } |
a8eecf22 | 5108 | EXPORT_SYMBOL_GPL(ftrace_dump); |
cf586b61 | 5109 | |
3928a8a2 | 5110 | __init static int tracer_alloc_buffers(void) |
bc0c38d1 | 5111 | { |
73c5162a | 5112 | int ring_buf_size; |
750912fa | 5113 | enum ring_buffer_flags rb_flags; |
4c11d7ae | 5114 | int i; |
9e01c1b7 | 5115 | int ret = -ENOMEM; |
4c11d7ae | 5116 | |
750912fa | 5117 | |
9e01c1b7 RR |
5118 | if (!alloc_cpumask_var(&tracing_buffer_mask, GFP_KERNEL)) |
5119 | goto out; | |
5120 | ||
5121 | if (!alloc_cpumask_var(&tracing_cpumask, GFP_KERNEL)) | |
5122 | goto out_free_buffer_mask; | |
4c11d7ae | 5123 | |
07d777fe SR |
5124 | /* Only allocate trace_printk buffers if a trace_printk exists */ |
5125 | if (__stop___trace_bprintk_fmt != __start___trace_bprintk_fmt) | |
81698831 | 5126 | /* Must be called before global_trace.buffer is allocated */ |
07d777fe SR |
5127 | trace_printk_init_buffers(); |
5128 | ||
73c5162a SR |
5129 | /* To save memory, keep the ring buffer size to its minimum */ |
5130 | if (ring_buffer_expanded) | |
5131 | ring_buf_size = trace_buf_size; | |
5132 | else | |
5133 | ring_buf_size = 1; | |
5134 | ||
750912fa DS |
5135 | rb_flags = trace_flags & TRACE_ITER_OVERWRITE ? RB_FL_OVERWRITE : 0; |
5136 | ||
9e01c1b7 RR |
5137 | cpumask_copy(tracing_buffer_mask, cpu_possible_mask); |
5138 | cpumask_copy(tracing_cpumask, cpu_all_mask); | |
5139 | ||
5140 | /* TODO: make the number of buffers hot pluggable with CPUS */ | |
750912fa | 5141 | global_trace.buffer = ring_buffer_alloc(ring_buf_size, rb_flags); |
3928a8a2 SR |
5142 | if (!global_trace.buffer) { |
5143 | printk(KERN_ERR "tracer: failed to allocate ring buffer!\n"); | |
5144 | WARN_ON(1); | |
9e01c1b7 | 5145 | goto out_free_cpumask; |
4c11d7ae | 5146 | } |
499e5470 SR |
5147 | if (global_trace.buffer_disabled) |
5148 | tracing_off(); | |
4c11d7ae | 5149 | |
9e01c1b7 | 5150 | |
4c11d7ae | 5151 | #ifdef CONFIG_TRACER_MAX_TRACE |
750912fa | 5152 | max_tr.buffer = ring_buffer_alloc(1, rb_flags); |
3928a8a2 SR |
5153 | if (!max_tr.buffer) { |
5154 | printk(KERN_ERR "tracer: failed to allocate max ring buffer!\n"); | |
5155 | WARN_ON(1); | |
5156 | ring_buffer_free(global_trace.buffer); | |
9e01c1b7 | 5157 | goto out_free_cpumask; |
4c11d7ae | 5158 | } |
a98a3c3f | 5159 | #endif |
ab46428c | 5160 | |
4c11d7ae | 5161 | /* Allocate the first page for all buffers */ |
ab46428c | 5162 | for_each_tracing_cpu(i) { |
566b0aaf | 5163 | global_trace.data[i] = &per_cpu(global_trace_cpu, i); |
9705f69e | 5164 | max_tr.data[i] = &per_cpu(max_tr_data, i); |
4c11d7ae | 5165 | } |
438ced17 | 5166 | |
a591c73f VN |
5167 | set_buffer_entries(&global_trace, |
5168 | ring_buffer_size(global_trace.buffer, 0)); | |
438ced17 VN |
5169 | #ifdef CONFIG_TRACER_MAX_TRACE |
5170 | set_buffer_entries(&max_tr, 1); | |
5171 | #endif | |
bc0c38d1 | 5172 | |
bc0c38d1 | 5173 | trace_init_cmdlines(); |
0d5c6e1c | 5174 | init_irq_work(&trace_work_wakeup, trace_wake_up); |
bc0c38d1 | 5175 | |
43a15386 | 5176 | register_tracer(&nop_trace); |
79fb0768 | 5177 | current_trace = &nop_trace; |
60a11774 SR |
5178 | /* All seems OK, enable tracing */ |
5179 | tracing_disabled = 0; | |
3928a8a2 | 5180 | |
3f5a54e3 SR |
5181 | atomic_notifier_chain_register(&panic_notifier_list, |
5182 | &trace_panic_notifier); | |
5183 | ||
5184 | register_die_notifier(&trace_die_notifier); | |
2fc1dfbe | 5185 | |
7bcfaf54 SR |
5186 | while (trace_boot_options) { |
5187 | char *option; | |
5188 | ||
5189 | option = strsep(&trace_boot_options, ","); | |
5190 | trace_set_options(option); | |
5191 | } | |
5192 | ||
2fc1dfbe | 5193 | return 0; |
3f5a54e3 | 5194 | |
9e01c1b7 RR |
5195 | out_free_cpumask: |
5196 | free_cpumask_var(tracing_cpumask); | |
5197 | out_free_buffer_mask: | |
5198 | free_cpumask_var(tracing_buffer_mask); | |
5199 | out: | |
5200 | return ret; | |
bc0c38d1 | 5201 | } |
b2821ae6 SR |
5202 | |
5203 | __init static int clear_boot_tracer(void) | |
5204 | { | |
5205 | /* | |
5206 | * The default tracer at boot buffer is an init section. | |
5207 | * This function is called in lateinit. If we did not | |
5208 | * find the boot tracer, then clear it out, to prevent | |
5209 | * later registration from accessing the buffer that is | |
5210 | * about to be freed. | |
5211 | */ | |
5212 | if (!default_bootup_tracer) | |
5213 | return 0; | |
5214 | ||
5215 | printk(KERN_INFO "ftrace bootup tracer '%s' not registered.\n", | |
5216 | default_bootup_tracer); | |
5217 | default_bootup_tracer = NULL; | |
5218 | ||
5219 | return 0; | |
5220 | } | |
5221 | ||
b5ad384e FW |
5222 | early_initcall(tracer_alloc_buffers); |
5223 | fs_initcall(tracer_init_debugfs); | |
b2821ae6 | 5224 | late_initcall(clear_boot_tracer); |