Commit | Line | Data |
---|---|---|
bc0c38d1 SR |
1 | /* |
2 | * ring buffer based function tracer | |
3 | * | |
4 | * Copyright (C) 2007-2008 Steven Rostedt <srostedt@redhat.com> | |
5 | * Copyright (C) 2008 Ingo Molnar <mingo@redhat.com> | |
6 | * | |
7 | * Originally taken from the RT patch by: | |
8 | * Arnaldo Carvalho de Melo <acme@redhat.com> | |
9 | * | |
10 | * Based on code from the latency_tracer, that is: | |
11 | * Copyright (C) 2004-2006 Ingo Molnar | |
12 | * Copyright (C) 2004 William Lee Irwin III | |
13 | */ | |
2cadf913 | 14 | #include <linux/ring_buffer.h> |
bc0c38d1 | 15 | #include <linux/utsrelease.h> |
2cadf913 SR |
16 | #include <linux/stacktrace.h> |
17 | #include <linux/writeback.h> | |
bc0c38d1 SR |
18 | #include <linux/kallsyms.h> |
19 | #include <linux/seq_file.h> | |
405f5571 | 20 | #include <linux/smp_lock.h> |
3f5a54e3 | 21 | #include <linux/notifier.h> |
2cadf913 | 22 | #include <linux/irqflags.h> |
bc0c38d1 | 23 | #include <linux/debugfs.h> |
4c11d7ae | 24 | #include <linux/pagemap.h> |
bc0c38d1 SR |
25 | #include <linux/hardirq.h> |
26 | #include <linux/linkage.h> | |
27 | #include <linux/uaccess.h> | |
2cadf913 | 28 | #include <linux/kprobes.h> |
bc0c38d1 SR |
29 | #include <linux/ftrace.h> |
30 | #include <linux/module.h> | |
31 | #include <linux/percpu.h> | |
2cadf913 | 32 | #include <linux/splice.h> |
3f5a54e3 | 33 | #include <linux/kdebug.h> |
5f0c6c03 | 34 | #include <linux/string.h> |
bc0c38d1 SR |
35 | #include <linux/ctype.h> |
36 | #include <linux/init.h> | |
2a2cc8f7 | 37 | #include <linux/poll.h> |
bc0c38d1 SR |
38 | #include <linux/gfp.h> |
39 | #include <linux/fs.h> | |
86387f7e | 40 | |
bc0c38d1 | 41 | #include "trace.h" |
f0868d1e | 42 | #include "trace_output.h" |
bc0c38d1 | 43 | |
3928a8a2 SR |
44 | #define TRACE_BUFFER_FLAGS (RB_FL_OVERWRITE) |
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 SR |
80 | |
81 | /* | |
82 | * Kill all tracing for good (never come back). | |
83 | * It is initialized to 1 but will turn to zero if the initialization | |
84 | * of the tracer is successful. But that is the only place that sets | |
85 | * this back to zero. | |
86 | */ | |
4fd27358 | 87 | static int tracing_disabled = 1; |
0f048701 | 88 | |
5e5bf483 | 89 | DEFINE_PER_CPU(local_t, ftrace_cpu_disabled); |
d769041f SR |
90 | |
91 | static inline void ftrace_disable_cpu(void) | |
92 | { | |
93 | preempt_disable(); | |
94 | local_inc(&__get_cpu_var(ftrace_cpu_disabled)); | |
95 | } | |
96 | ||
97 | static inline void ftrace_enable_cpu(void) | |
98 | { | |
99 | local_dec(&__get_cpu_var(ftrace_cpu_disabled)); | |
100 | preempt_enable(); | |
101 | } | |
102 | ||
9e01c1b7 | 103 | static cpumask_var_t __read_mostly tracing_buffer_mask; |
ab46428c | 104 | |
b04cc6b1 FW |
105 | /* Define which cpu buffers are currently read in trace_pipe */ |
106 | static cpumask_var_t tracing_reader_cpumask; | |
107 | ||
ab46428c | 108 | #define for_each_tracing_cpu(cpu) \ |
9e01c1b7 | 109 | for_each_cpu(cpu, tracing_buffer_mask) |
ab46428c | 110 | |
944ac425 SR |
111 | /* |
112 | * ftrace_dump_on_oops - variable to dump ftrace buffer on oops | |
113 | * | |
114 | * If there is an oops (or kernel panic) and the ftrace_dump_on_oops | |
115 | * is set, then ftrace_dump is called. This will output the contents | |
116 | * of the ftrace buffers to the console. This is very useful for | |
117 | * capturing traces that lead to crashes and outputing it to a | |
118 | * serial console. | |
119 | * | |
120 | * It is default off, but you can enable it with either specifying | |
121 | * "ftrace_dump_on_oops" in the kernel command line, or setting | |
122 | * /proc/sys/kernel/ftrace_dump_on_oops to true. | |
123 | */ | |
124 | int ftrace_dump_on_oops; | |
125 | ||
b2821ae6 SR |
126 | static int tracing_set_tracer(const char *buf); |
127 | ||
128 | #define BOOTUP_TRACER_SIZE 100 | |
129 | static char bootup_tracer_buf[BOOTUP_TRACER_SIZE] __initdata; | |
130 | static char *default_bootup_tracer; | |
d9e54076 PZ |
131 | |
132 | static int __init set_ftrace(char *str) | |
133 | { | |
b2821ae6 SR |
134 | strncpy(bootup_tracer_buf, str, BOOTUP_TRACER_SIZE); |
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 | } | |
b2821ae6 | 140 | __setup("ftrace=", set_ftrace); |
d9e54076 | 141 | |
944ac425 SR |
142 | static int __init set_ftrace_dump_on_oops(char *str) |
143 | { | |
144 | ftrace_dump_on_oops = 1; | |
145 | return 1; | |
146 | } | |
147 | __setup("ftrace_dump_on_oops", set_ftrace_dump_on_oops); | |
60a11774 | 148 | |
cf8e3474 | 149 | unsigned long long ns2usecs(cycle_t nsec) |
bc0c38d1 SR |
150 | { |
151 | nsec += 500; | |
152 | do_div(nsec, 1000); | |
153 | return nsec; | |
154 | } | |
155 | ||
4fcdae83 SR |
156 | /* |
157 | * The global_trace is the descriptor that holds the tracing | |
158 | * buffers for the live tracing. For each CPU, it contains | |
159 | * a link list of pages that will store trace entries. The | |
160 | * page descriptor of the pages in the memory is used to hold | |
161 | * the link list by linking the lru item in the page descriptor | |
162 | * to each of the pages in the buffer per CPU. | |
163 | * | |
164 | * For each active CPU there is a data field that holds the | |
165 | * pages for the buffer for that CPU. Each CPU has the same number | |
166 | * of pages allocated for its buffer. | |
167 | */ | |
bc0c38d1 SR |
168 | static struct trace_array global_trace; |
169 | ||
170 | static DEFINE_PER_CPU(struct trace_array_cpu, global_trace_cpu); | |
171 | ||
e77405ad SR |
172 | int filter_current_check_discard(struct ring_buffer *buffer, |
173 | struct ftrace_event_call *call, void *rec, | |
eb02ce01 TZ |
174 | struct ring_buffer_event *event) |
175 | { | |
e77405ad | 176 | return filter_check_discard(call, rec, buffer, event); |
eb02ce01 | 177 | } |
17c873ec | 178 | EXPORT_SYMBOL_GPL(filter_current_check_discard); |
eb02ce01 | 179 | |
37886f6a SR |
180 | cycle_t ftrace_now(int cpu) |
181 | { | |
182 | u64 ts; | |
183 | ||
184 | /* Early boot up does not have a buffer yet */ | |
185 | if (!global_trace.buffer) | |
186 | return trace_clock_local(); | |
187 | ||
188 | ts = ring_buffer_time_stamp(global_trace.buffer, cpu); | |
189 | ring_buffer_normalize_time_stamp(global_trace.buffer, cpu, &ts); | |
190 | ||
191 | return ts; | |
192 | } | |
bc0c38d1 | 193 | |
4fcdae83 SR |
194 | /* |
195 | * The max_tr is used to snapshot the global_trace when a maximum | |
196 | * latency is reached. Some tracers will use this to store a maximum | |
197 | * trace while it continues examining live traces. | |
198 | * | |
199 | * The buffers for the max_tr are set up the same as the global_trace. | |
200 | * When a snapshot is taken, the link list of the max_tr is swapped | |
201 | * with the link list of the global_trace and the buffers are reset for | |
202 | * the global_trace so the tracing can continue. | |
203 | */ | |
bc0c38d1 SR |
204 | static struct trace_array max_tr; |
205 | ||
206 | static DEFINE_PER_CPU(struct trace_array_cpu, max_data); | |
207 | ||
4fcdae83 | 208 | /* tracer_enabled is used to toggle activation of a tracer */ |
26994ead | 209 | static int tracer_enabled = 1; |
4fcdae83 | 210 | |
9036990d SR |
211 | /** |
212 | * tracing_is_enabled - return tracer_enabled status | |
213 | * | |
214 | * This function is used by other tracers to know the status | |
215 | * of the tracer_enabled flag. Tracers may use this function | |
216 | * to know if it should enable their features when starting | |
217 | * up. See irqsoff tracer for an example (start_irqsoff_tracer). | |
218 | */ | |
219 | int tracing_is_enabled(void) | |
220 | { | |
221 | return tracer_enabled; | |
222 | } | |
223 | ||
4fcdae83 | 224 | /* |
3928a8a2 SR |
225 | * trace_buf_size is the size in bytes that is allocated |
226 | * for a buffer. Note, the number of bytes is always rounded | |
227 | * to page size. | |
3f5a54e3 SR |
228 | * |
229 | * This number is purposely set to a low number of 16384. | |
230 | * If the dump on oops happens, it will be much appreciated | |
231 | * to not have to wait for all that output. Anyway this can be | |
232 | * boot time and run time configurable. | |
4fcdae83 | 233 | */ |
3928a8a2 | 234 | #define TRACE_BUF_SIZE_DEFAULT 1441792UL /* 16384 * 88 (sizeof(entry)) */ |
3f5a54e3 | 235 | |
3928a8a2 | 236 | static unsigned long trace_buf_size = TRACE_BUF_SIZE_DEFAULT; |
bc0c38d1 | 237 | |
4fcdae83 | 238 | /* trace_types holds a link list of available tracers. */ |
bc0c38d1 | 239 | static struct tracer *trace_types __read_mostly; |
4fcdae83 SR |
240 | |
241 | /* current_trace points to the tracer that is currently active */ | |
bc0c38d1 | 242 | static struct tracer *current_trace __read_mostly; |
4fcdae83 SR |
243 | |
244 | /* | |
245 | * max_tracer_type_len is used to simplify the allocating of | |
246 | * buffers to read userspace tracer names. We keep track of | |
247 | * the longest tracer name registered. | |
248 | */ | |
bc0c38d1 SR |
249 | static int max_tracer_type_len; |
250 | ||
4fcdae83 SR |
251 | /* |
252 | * trace_types_lock is used to protect the trace_types list. | |
253 | * This lock is also used to keep user access serialized. | |
254 | * Accesses from userspace will grab this lock while userspace | |
255 | * activities happen inside the kernel. | |
256 | */ | |
bc0c38d1 | 257 | static DEFINE_MUTEX(trace_types_lock); |
4fcdae83 SR |
258 | |
259 | /* trace_wait is a waitqueue for tasks blocked on trace_poll */ | |
4e655519 IM |
260 | static DECLARE_WAIT_QUEUE_HEAD(trace_wait); |
261 | ||
ee6bce52 | 262 | /* trace_flags holds trace_options default values */ |
12ef7d44 | 263 | unsigned long trace_flags = TRACE_ITER_PRINT_PARENT | TRACE_ITER_PRINTK | |
a2a16d6a SR |
264 | TRACE_ITER_ANNOTATE | TRACE_ITER_CONTEXT_INFO | TRACE_ITER_SLEEP_TIME | |
265 | TRACE_ITER_GRAPH_TIME; | |
4e655519 | 266 | |
b8de7bd1 SR |
267 | static int trace_stop_count; |
268 | static DEFINE_SPINLOCK(tracing_start_lock); | |
269 | ||
4fcdae83 SR |
270 | /** |
271 | * trace_wake_up - wake up tasks waiting for trace input | |
272 | * | |
273 | * Simply wakes up any task that is blocked on the trace_wait | |
274 | * queue. These is used with trace_poll for tasks polling the trace. | |
275 | */ | |
4e655519 IM |
276 | void trace_wake_up(void) |
277 | { | |
017730c1 IM |
278 | /* |
279 | * The runqueue_is_locked() can fail, but this is the best we | |
280 | * have for now: | |
281 | */ | |
282 | if (!(trace_flags & TRACE_ITER_BLOCK) && !runqueue_is_locked()) | |
4e655519 IM |
283 | wake_up(&trace_wait); |
284 | } | |
bc0c38d1 | 285 | |
3928a8a2 | 286 | static int __init set_buf_size(char *str) |
bc0c38d1 | 287 | { |
3928a8a2 | 288 | unsigned long buf_size; |
c6caeeb1 | 289 | |
bc0c38d1 SR |
290 | if (!str) |
291 | return 0; | |
9d612bef | 292 | buf_size = memparse(str, &str); |
c6caeeb1 | 293 | /* nr_entries can not be zero */ |
9d612bef | 294 | if (buf_size == 0) |
c6caeeb1 | 295 | return 0; |
3928a8a2 | 296 | trace_buf_size = buf_size; |
bc0c38d1 SR |
297 | return 1; |
298 | } | |
3928a8a2 | 299 | __setup("trace_buf_size=", set_buf_size); |
bc0c38d1 | 300 | |
57f50be1 SR |
301 | unsigned long nsecs_to_usecs(unsigned long nsecs) |
302 | { | |
303 | return nsecs / 1000; | |
304 | } | |
305 | ||
4fcdae83 | 306 | /* These must match the bit postions in trace_iterator_flags */ |
bc0c38d1 SR |
307 | static const char *trace_options[] = { |
308 | "print-parent", | |
309 | "sym-offset", | |
310 | "sym-addr", | |
311 | "verbose", | |
f9896bf3 | 312 | "raw", |
5e3ca0ec | 313 | "hex", |
cb0f12aa | 314 | "bin", |
2a2cc8f7 | 315 | "block", |
86387f7e | 316 | "stacktrace", |
4ac3ba41 | 317 | "sched-tree", |
5e1607a0 | 318 | "trace_printk", |
b2a866f9 | 319 | "ftrace_preempt", |
9f029e83 | 320 | "branch", |
12ef7d44 | 321 | "annotate", |
02b67518 | 322 | "userstacktrace", |
b54d3de9 | 323 | "sym-userobj", |
66896a85 | 324 | "printk-msg-only", |
c4a8e8be | 325 | "context-info", |
c032ef64 | 326 | "latency-format", |
be6f164a | 327 | "sleep-time", |
a2a16d6a | 328 | "graph-time", |
bc0c38d1 SR |
329 | NULL |
330 | }; | |
331 | ||
5079f326 Z |
332 | static struct { |
333 | u64 (*func)(void); | |
334 | const char *name; | |
335 | } trace_clocks[] = { | |
336 | { trace_clock_local, "local" }, | |
337 | { trace_clock_global, "global" }, | |
338 | }; | |
339 | ||
340 | int trace_clock_id; | |
341 | ||
6c6c2796 PP |
342 | ssize_t trace_seq_to_user(struct trace_seq *s, char __user *ubuf, size_t cnt) |
343 | { | |
344 | int len; | |
345 | int ret; | |
346 | ||
2dc5d12b SR |
347 | if (!cnt) |
348 | return 0; | |
349 | ||
6c6c2796 PP |
350 | if (s->len <= s->readpos) |
351 | return -EBUSY; | |
352 | ||
353 | len = s->len - s->readpos; | |
354 | if (cnt > len) | |
355 | cnt = len; | |
356 | ret = copy_to_user(ubuf, s->buffer + s->readpos, cnt); | |
2dc5d12b | 357 | if (ret == cnt) |
6c6c2796 PP |
358 | return -EFAULT; |
359 | ||
2dc5d12b SR |
360 | cnt -= ret; |
361 | ||
e74da523 | 362 | s->readpos += cnt; |
6c6c2796 | 363 | return cnt; |
214023c3 SR |
364 | } |
365 | ||
b8b94265 | 366 | static ssize_t trace_seq_to_buffer(struct trace_seq *s, void *buf, size_t cnt) |
3c56819b EGM |
367 | { |
368 | int len; | |
369 | void *ret; | |
370 | ||
371 | if (s->len <= s->readpos) | |
372 | return -EBUSY; | |
373 | ||
374 | len = s->len - s->readpos; | |
375 | if (cnt > len) | |
376 | cnt = len; | |
377 | ret = memcpy(buf, s->buffer + s->readpos, cnt); | |
378 | if (!ret) | |
379 | return -EFAULT; | |
380 | ||
e74da523 | 381 | s->readpos += cnt; |
3c56819b EGM |
382 | return cnt; |
383 | } | |
384 | ||
5d4a9dba SR |
385 | /* |
386 | * ftrace_max_lock is used to protect the swapping of buffers | |
387 | * when taking a max snapshot. The buffers themselves are | |
388 | * protected by per_cpu spinlocks. But the action of the swap | |
389 | * needs its own lock. | |
390 | * | |
391 | * This is defined as a raw_spinlock_t in order to help | |
392 | * with performance when lockdep debugging is enabled. | |
393 | * | |
394 | * It is also used in other places outside the update_max_tr | |
395 | * so it needs to be defined outside of the | |
396 | * CONFIG_TRACER_MAX_TRACE. | |
397 | */ | |
398 | static raw_spinlock_t ftrace_max_lock = | |
399 | (raw_spinlock_t)__RAW_SPIN_LOCK_UNLOCKED; | |
400 | ||
401 | #ifdef CONFIG_TRACER_MAX_TRACE | |
402 | unsigned long __read_mostly tracing_max_latency; | |
403 | unsigned long __read_mostly tracing_thresh; | |
404 | ||
405 | /* | |
406 | * Copy the new maximum trace into the separate maximum-trace | |
407 | * structure. (this way the maximum trace is permanently saved, | |
408 | * for later retrieval via /sys/kernel/debug/tracing/latency_trace) | |
409 | */ | |
410 | static void | |
411 | __update_max_tr(struct trace_array *tr, struct task_struct *tsk, int cpu) | |
412 | { | |
413 | struct trace_array_cpu *data = tr->data[cpu]; | |
8248ac05 | 414 | struct trace_array_cpu *max_data = tr->data[cpu]; |
5d4a9dba SR |
415 | |
416 | max_tr.cpu = cpu; | |
417 | max_tr.time_start = data->preempt_timestamp; | |
418 | ||
8248ac05 SR |
419 | max_data = max_tr.data[cpu]; |
420 | max_data->saved_latency = tracing_max_latency; | |
421 | max_data->critical_start = data->critical_start; | |
422 | max_data->critical_end = data->critical_end; | |
5d4a9dba SR |
423 | |
424 | memcpy(data->comm, tsk->comm, TASK_COMM_LEN); | |
8248ac05 SR |
425 | max_data->pid = tsk->pid; |
426 | max_data->uid = task_uid(tsk); | |
427 | max_data->nice = tsk->static_prio - 20 - MAX_RT_PRIO; | |
428 | max_data->policy = tsk->policy; | |
429 | max_data->rt_priority = tsk->rt_priority; | |
5d4a9dba SR |
430 | |
431 | /* record this tasks comm */ | |
432 | tracing_record_cmdline(tsk); | |
433 | } | |
434 | ||
4fcdae83 SR |
435 | /** |
436 | * update_max_tr - snapshot all trace buffers from global_trace to max_tr | |
437 | * @tr: tracer | |
438 | * @tsk: the task with the latency | |
439 | * @cpu: The cpu that initiated the trace. | |
440 | * | |
441 | * Flip the buffers between the @tr and the max_tr and record information | |
442 | * about which task was the cause of this latency. | |
443 | */ | |
e309b41d | 444 | void |
bc0c38d1 SR |
445 | update_max_tr(struct trace_array *tr, struct task_struct *tsk, int cpu) |
446 | { | |
3928a8a2 | 447 | struct ring_buffer *buf = tr->buffer; |
bc0c38d1 | 448 | |
b8de7bd1 SR |
449 | if (trace_stop_count) |
450 | return; | |
451 | ||
4c11d7ae | 452 | WARN_ON_ONCE(!irqs_disabled()); |
92205c23 | 453 | __raw_spin_lock(&ftrace_max_lock); |
3928a8a2 SR |
454 | |
455 | tr->buffer = max_tr.buffer; | |
456 | max_tr.buffer = buf; | |
457 | ||
bc0c38d1 | 458 | __update_max_tr(tr, tsk, cpu); |
92205c23 | 459 | __raw_spin_unlock(&ftrace_max_lock); |
bc0c38d1 SR |
460 | } |
461 | ||
462 | /** | |
463 | * update_max_tr_single - only copy one trace over, and reset the rest | |
464 | * @tr - tracer | |
465 | * @tsk - task with the latency | |
466 | * @cpu - the cpu of the buffer to copy. | |
4fcdae83 SR |
467 | * |
468 | * Flip the trace of a single CPU buffer between the @tr and the max_tr. | |
bc0c38d1 | 469 | */ |
e309b41d | 470 | void |
bc0c38d1 SR |
471 | update_max_tr_single(struct trace_array *tr, struct task_struct *tsk, int cpu) |
472 | { | |
3928a8a2 | 473 | int ret; |
bc0c38d1 | 474 | |
b8de7bd1 SR |
475 | if (trace_stop_count) |
476 | return; | |
477 | ||
4c11d7ae | 478 | WARN_ON_ONCE(!irqs_disabled()); |
92205c23 | 479 | __raw_spin_lock(&ftrace_max_lock); |
bc0c38d1 | 480 | |
d769041f SR |
481 | ftrace_disable_cpu(); |
482 | ||
3928a8a2 SR |
483 | ret = ring_buffer_swap_cpu(max_tr.buffer, tr->buffer, cpu); |
484 | ||
e8165dbb SR |
485 | if (ret == -EBUSY) { |
486 | /* | |
487 | * We failed to swap the buffer due to a commit taking | |
488 | * place on this CPU. We fail to record, but we reset | |
489 | * the max trace buffer (no one writes directly to it) | |
490 | * and flag that it failed. | |
491 | */ | |
492 | trace_array_printk(&max_tr, _THIS_IP_, | |
493 | "Failed to swap buffers due to commit in progress\n"); | |
494 | } | |
495 | ||
d769041f SR |
496 | ftrace_enable_cpu(); |
497 | ||
e8165dbb | 498 | WARN_ON_ONCE(ret && ret != -EAGAIN && ret != -EBUSY); |
bc0c38d1 SR |
499 | |
500 | __update_max_tr(tr, tsk, cpu); | |
92205c23 | 501 | __raw_spin_unlock(&ftrace_max_lock); |
bc0c38d1 | 502 | } |
5d4a9dba | 503 | #endif /* CONFIG_TRACER_MAX_TRACE */ |
bc0c38d1 | 504 | |
4fcdae83 SR |
505 | /** |
506 | * register_tracer - register a tracer with the ftrace system. | |
507 | * @type - the plugin for the tracer | |
508 | * | |
509 | * Register a new plugin tracer. | |
510 | */ | |
bc0c38d1 | 511 | int register_tracer(struct tracer *type) |
e7669b8e HE |
512 | __releases(kernel_lock) |
513 | __acquires(kernel_lock) | |
bc0c38d1 SR |
514 | { |
515 | struct tracer *t; | |
516 | int len; | |
517 | int ret = 0; | |
518 | ||
519 | if (!type->name) { | |
520 | pr_info("Tracer must have a name\n"); | |
521 | return -1; | |
522 | } | |
523 | ||
86fa2f60 IM |
524 | /* |
525 | * When this gets called we hold the BKL which means that | |
526 | * preemption is disabled. Various trace selftests however | |
527 | * need to disable and enable preemption for successful tests. | |
528 | * So we drop the BKL here and grab it after the tests again. | |
529 | */ | |
530 | unlock_kernel(); | |
bc0c38d1 | 531 | mutex_lock(&trace_types_lock); |
86fa2f60 | 532 | |
8e1b82e0 FW |
533 | tracing_selftest_running = true; |
534 | ||
bc0c38d1 SR |
535 | for (t = trace_types; t; t = t->next) { |
536 | if (strcmp(type->name, t->name) == 0) { | |
537 | /* already found */ | |
538 | pr_info("Trace %s already registered\n", | |
539 | type->name); | |
540 | ret = -1; | |
541 | goto out; | |
542 | } | |
543 | } | |
544 | ||
adf9f195 FW |
545 | if (!type->set_flag) |
546 | type->set_flag = &dummy_set_flag; | |
547 | if (!type->flags) | |
548 | type->flags = &dummy_tracer_flags; | |
549 | else | |
550 | if (!type->flags->opts) | |
551 | type->flags->opts = dummy_tracer_opt; | |
6eaaa5d5 FW |
552 | if (!type->wait_pipe) |
553 | type->wait_pipe = default_wait_pipe; | |
554 | ||
adf9f195 | 555 | |
60a11774 | 556 | #ifdef CONFIG_FTRACE_STARTUP_TEST |
b2821ae6 | 557 | if (type->selftest && !tracing_selftest_disabled) { |
60a11774 | 558 | struct tracer *saved_tracer = current_trace; |
60a11774 | 559 | struct trace_array *tr = &global_trace; |
ff32504f | 560 | |
60a11774 SR |
561 | /* |
562 | * Run a selftest on this tracer. | |
563 | * Here we reset the trace buffer, and set the current | |
564 | * tracer to be this tracer. The tracer can then run some | |
565 | * internal tracing to verify that everything is in order. | |
566 | * If we fail, we do not register this tracer. | |
567 | */ | |
76f0d073 | 568 | tracing_reset_online_cpus(tr); |
86fa2f60 | 569 | |
60a11774 | 570 | current_trace = type; |
60a11774 SR |
571 | /* the test is responsible for initializing and enabling */ |
572 | pr_info("Testing tracer %s: ", type->name); | |
573 | ret = type->selftest(type, tr); | |
574 | /* the test is responsible for resetting too */ | |
575 | current_trace = saved_tracer; | |
60a11774 SR |
576 | if (ret) { |
577 | printk(KERN_CONT "FAILED!\n"); | |
578 | goto out; | |
579 | } | |
1d4db00a | 580 | /* Only reset on passing, to avoid touching corrupted buffers */ |
76f0d073 | 581 | tracing_reset_online_cpus(tr); |
86fa2f60 | 582 | |
60a11774 SR |
583 | printk(KERN_CONT "PASSED\n"); |
584 | } | |
585 | #endif | |
586 | ||
bc0c38d1 SR |
587 | type->next = trace_types; |
588 | trace_types = type; | |
589 | len = strlen(type->name); | |
590 | if (len > max_tracer_type_len) | |
591 | max_tracer_type_len = len; | |
60a11774 | 592 | |
bc0c38d1 | 593 | out: |
8e1b82e0 | 594 | tracing_selftest_running = false; |
bc0c38d1 SR |
595 | mutex_unlock(&trace_types_lock); |
596 | ||
dac74940 SR |
597 | if (ret || !default_bootup_tracer) |
598 | goto out_unlock; | |
599 | ||
600 | if (strncmp(default_bootup_tracer, type->name, BOOTUP_TRACER_SIZE)) | |
601 | goto out_unlock; | |
602 | ||
603 | printk(KERN_INFO "Starting tracer '%s'\n", type->name); | |
604 | /* Do we want this tracer to start on bootup? */ | |
605 | tracing_set_tracer(type->name); | |
606 | default_bootup_tracer = NULL; | |
607 | /* disable other selftests, since this will break it. */ | |
608 | tracing_selftest_disabled = 1; | |
b2821ae6 | 609 | #ifdef CONFIG_FTRACE_STARTUP_TEST |
dac74940 SR |
610 | printk(KERN_INFO "Disabling FTRACE selftests due to running tracer '%s'\n", |
611 | type->name); | |
b2821ae6 | 612 | #endif |
b2821ae6 | 613 | |
dac74940 | 614 | out_unlock: |
b2821ae6 | 615 | lock_kernel(); |
bc0c38d1 SR |
616 | return ret; |
617 | } | |
618 | ||
619 | void unregister_tracer(struct tracer *type) | |
620 | { | |
621 | struct tracer **t; | |
622 | int len; | |
623 | ||
624 | mutex_lock(&trace_types_lock); | |
625 | for (t = &trace_types; *t; t = &(*t)->next) { | |
626 | if (*t == type) | |
627 | goto found; | |
628 | } | |
629 | pr_info("Trace %s not registered\n", type->name); | |
630 | goto out; | |
631 | ||
632 | found: | |
633 | *t = (*t)->next; | |
b5db03c4 ACM |
634 | |
635 | if (type == current_trace && tracer_enabled) { | |
636 | tracer_enabled = 0; | |
637 | tracing_stop(); | |
638 | if (current_trace->stop) | |
639 | current_trace->stop(&global_trace); | |
640 | current_trace = &nop_trace; | |
641 | } | |
642 | ||
bc0c38d1 SR |
643 | if (strlen(type->name) != max_tracer_type_len) |
644 | goto out; | |
645 | ||
646 | max_tracer_type_len = 0; | |
647 | for (t = &trace_types; *t; t = &(*t)->next) { | |
648 | len = strlen((*t)->name); | |
649 | if (len > max_tracer_type_len) | |
650 | max_tracer_type_len = len; | |
651 | } | |
652 | out: | |
653 | mutex_unlock(&trace_types_lock); | |
654 | } | |
655 | ||
f633903a | 656 | static void __tracing_reset(struct trace_array *tr, int cpu) |
bc0c38d1 | 657 | { |
d769041f | 658 | ftrace_disable_cpu(); |
3928a8a2 | 659 | ring_buffer_reset_cpu(tr->buffer, cpu); |
d769041f | 660 | ftrace_enable_cpu(); |
bc0c38d1 SR |
661 | } |
662 | ||
f633903a SR |
663 | void tracing_reset(struct trace_array *tr, int cpu) |
664 | { | |
665 | struct ring_buffer *buffer = tr->buffer; | |
666 | ||
667 | ring_buffer_record_disable(buffer); | |
668 | ||
669 | /* Make sure all commits have finished */ | |
670 | synchronize_sched(); | |
671 | __tracing_reset(tr, cpu); | |
672 | ||
673 | ring_buffer_record_enable(buffer); | |
674 | } | |
675 | ||
213cc060 PE |
676 | void tracing_reset_online_cpus(struct trace_array *tr) |
677 | { | |
621968cd | 678 | struct ring_buffer *buffer = tr->buffer; |
213cc060 PE |
679 | int cpu; |
680 | ||
621968cd SR |
681 | ring_buffer_record_disable(buffer); |
682 | ||
683 | /* Make sure all commits have finished */ | |
684 | synchronize_sched(); | |
685 | ||
213cc060 PE |
686 | tr->time_start = ftrace_now(tr->cpu); |
687 | ||
688 | for_each_online_cpu(cpu) | |
f633903a | 689 | __tracing_reset(tr, cpu); |
621968cd SR |
690 | |
691 | ring_buffer_record_enable(buffer); | |
213cc060 PE |
692 | } |
693 | ||
9456f0fa SR |
694 | void tracing_reset_current(int cpu) |
695 | { | |
696 | tracing_reset(&global_trace, cpu); | |
697 | } | |
698 | ||
699 | void tracing_reset_current_online_cpus(void) | |
700 | { | |
701 | tracing_reset_online_cpus(&global_trace); | |
702 | } | |
703 | ||
bc0c38d1 | 704 | #define SAVED_CMDLINES 128 |
2c7eea4c | 705 | #define NO_CMDLINE_MAP UINT_MAX |
bc0c38d1 SR |
706 | static unsigned map_pid_to_cmdline[PID_MAX_DEFAULT+1]; |
707 | static unsigned map_cmdline_to_pid[SAVED_CMDLINES]; | |
708 | static char saved_cmdlines[SAVED_CMDLINES][TASK_COMM_LEN]; | |
709 | static int cmdline_idx; | |
efed792d | 710 | static raw_spinlock_t trace_cmdline_lock = __RAW_SPIN_LOCK_UNLOCKED; |
25b0b44a | 711 | |
25b0b44a | 712 | /* temporary disable recording */ |
4fd27358 | 713 | static atomic_t trace_record_cmdline_disabled __read_mostly; |
bc0c38d1 SR |
714 | |
715 | static void trace_init_cmdlines(void) | |
716 | { | |
2c7eea4c TG |
717 | memset(&map_pid_to_cmdline, NO_CMDLINE_MAP, sizeof(map_pid_to_cmdline)); |
718 | memset(&map_cmdline_to_pid, NO_CMDLINE_MAP, sizeof(map_cmdline_to_pid)); | |
bc0c38d1 SR |
719 | cmdline_idx = 0; |
720 | } | |
721 | ||
69bb54ec SR |
722 | /** |
723 | * ftrace_off_permanent - disable all ftrace code permanently | |
724 | * | |
725 | * This should only be called when a serious anomally has | |
726 | * been detected. This will turn off the function tracing, | |
727 | * ring buffers, and other tracing utilites. It takes no | |
728 | * locks and can be called from any context. | |
729 | */ | |
730 | void ftrace_off_permanent(void) | |
731 | { | |
732 | tracing_disabled = 1; | |
733 | ftrace_stop(); | |
734 | tracing_off_permanent(); | |
735 | } | |
736 | ||
0f048701 SR |
737 | /** |
738 | * tracing_start - quick start of the tracer | |
739 | * | |
740 | * If tracing is enabled but was stopped by tracing_stop, | |
741 | * this will start the tracer back up. | |
742 | */ | |
743 | void tracing_start(void) | |
744 | { | |
745 | struct ring_buffer *buffer; | |
746 | unsigned long flags; | |
747 | ||
748 | if (tracing_disabled) | |
749 | return; | |
750 | ||
751 | spin_lock_irqsave(&tracing_start_lock, flags); | |
b06a8301 SR |
752 | if (--trace_stop_count) { |
753 | if (trace_stop_count < 0) { | |
754 | /* Someone screwed up their debugging */ | |
755 | WARN_ON_ONCE(1); | |
756 | trace_stop_count = 0; | |
757 | } | |
0f048701 SR |
758 | goto out; |
759 | } | |
760 | ||
761 | ||
762 | buffer = global_trace.buffer; | |
763 | if (buffer) | |
764 | ring_buffer_record_enable(buffer); | |
765 | ||
766 | buffer = max_tr.buffer; | |
767 | if (buffer) | |
768 | ring_buffer_record_enable(buffer); | |
769 | ||
770 | ftrace_start(); | |
771 | out: | |
772 | spin_unlock_irqrestore(&tracing_start_lock, flags); | |
773 | } | |
774 | ||
775 | /** | |
776 | * tracing_stop - quick stop of the tracer | |
777 | * | |
778 | * Light weight way to stop tracing. Use in conjunction with | |
779 | * tracing_start. | |
780 | */ | |
781 | void tracing_stop(void) | |
782 | { | |
783 | struct ring_buffer *buffer; | |
784 | unsigned long flags; | |
785 | ||
786 | ftrace_stop(); | |
787 | spin_lock_irqsave(&tracing_start_lock, flags); | |
788 | if (trace_stop_count++) | |
789 | goto out; | |
790 | ||
791 | buffer = global_trace.buffer; | |
792 | if (buffer) | |
793 | ring_buffer_record_disable(buffer); | |
794 | ||
795 | buffer = max_tr.buffer; | |
796 | if (buffer) | |
797 | ring_buffer_record_disable(buffer); | |
798 | ||
799 | out: | |
800 | spin_unlock_irqrestore(&tracing_start_lock, flags); | |
801 | } | |
802 | ||
e309b41d | 803 | void trace_stop_cmdline_recording(void); |
bc0c38d1 | 804 | |
e309b41d | 805 | static void trace_save_cmdline(struct task_struct *tsk) |
bc0c38d1 | 806 | { |
a635cf04 | 807 | unsigned pid, idx; |
bc0c38d1 SR |
808 | |
809 | if (!tsk->pid || unlikely(tsk->pid > PID_MAX_DEFAULT)) | |
810 | return; | |
811 | ||
812 | /* | |
813 | * It's not the end of the world if we don't get | |
814 | * the lock, but we also don't want to spin | |
815 | * nor do we want to disable interrupts, | |
816 | * so if we miss here, then better luck next time. | |
817 | */ | |
efed792d | 818 | if (!__raw_spin_trylock(&trace_cmdline_lock)) |
bc0c38d1 SR |
819 | return; |
820 | ||
821 | idx = map_pid_to_cmdline[tsk->pid]; | |
2c7eea4c | 822 | if (idx == NO_CMDLINE_MAP) { |
bc0c38d1 SR |
823 | idx = (cmdline_idx + 1) % SAVED_CMDLINES; |
824 | ||
a635cf04 CE |
825 | /* |
826 | * Check whether the cmdline buffer at idx has a pid | |
827 | * mapped. We are going to overwrite that entry so we | |
828 | * need to clear the map_pid_to_cmdline. Otherwise we | |
829 | * would read the new comm for the old pid. | |
830 | */ | |
831 | pid = map_cmdline_to_pid[idx]; | |
832 | if (pid != NO_CMDLINE_MAP) | |
833 | map_pid_to_cmdline[pid] = NO_CMDLINE_MAP; | |
bc0c38d1 | 834 | |
a635cf04 | 835 | map_cmdline_to_pid[idx] = tsk->pid; |
bc0c38d1 SR |
836 | map_pid_to_cmdline[tsk->pid] = idx; |
837 | ||
838 | cmdline_idx = idx; | |
839 | } | |
840 | ||
841 | memcpy(&saved_cmdlines[idx], tsk->comm, TASK_COMM_LEN); | |
842 | ||
efed792d | 843 | __raw_spin_unlock(&trace_cmdline_lock); |
bc0c38d1 SR |
844 | } |
845 | ||
4ca53085 | 846 | void trace_find_cmdline(int pid, char comm[]) |
bc0c38d1 | 847 | { |
bc0c38d1 SR |
848 | unsigned map; |
849 | ||
4ca53085 SR |
850 | if (!pid) { |
851 | strcpy(comm, "<idle>"); | |
852 | return; | |
853 | } | |
bc0c38d1 | 854 | |
4ca53085 SR |
855 | if (pid > PID_MAX_DEFAULT) { |
856 | strcpy(comm, "<...>"); | |
857 | return; | |
858 | } | |
bc0c38d1 | 859 | |
5b6045a9 | 860 | preempt_disable(); |
4ca53085 | 861 | __raw_spin_lock(&trace_cmdline_lock); |
bc0c38d1 | 862 | map = map_pid_to_cmdline[pid]; |
50d88758 TG |
863 | if (map != NO_CMDLINE_MAP) |
864 | strcpy(comm, saved_cmdlines[map]); | |
865 | else | |
866 | strcpy(comm, "<...>"); | |
bc0c38d1 | 867 | |
4ca53085 | 868 | __raw_spin_unlock(&trace_cmdline_lock); |
5b6045a9 | 869 | preempt_enable(); |
bc0c38d1 SR |
870 | } |
871 | ||
e309b41d | 872 | void tracing_record_cmdline(struct task_struct *tsk) |
bc0c38d1 | 873 | { |
18aecd36 TG |
874 | if (atomic_read(&trace_record_cmdline_disabled) || !tracer_enabled || |
875 | !tracing_is_on()) | |
bc0c38d1 SR |
876 | return; |
877 | ||
878 | trace_save_cmdline(tsk); | |
879 | } | |
880 | ||
45dcd8b8 | 881 | void |
38697053 SR |
882 | tracing_generic_entry_update(struct trace_entry *entry, unsigned long flags, |
883 | int pc) | |
bc0c38d1 SR |
884 | { |
885 | struct task_struct *tsk = current; | |
bc0c38d1 | 886 | |
777e208d SR |
887 | entry->preempt_count = pc & 0xff; |
888 | entry->pid = (tsk) ? tsk->pid : 0; | |
ef18012b | 889 | entry->tgid = (tsk) ? tsk->tgid : 0; |
777e208d | 890 | entry->flags = |
9244489a | 891 | #ifdef CONFIG_TRACE_IRQFLAGS_SUPPORT |
2e2ca155 | 892 | (irqs_disabled_flags(flags) ? TRACE_FLAG_IRQS_OFF : 0) | |
9244489a SR |
893 | #else |
894 | TRACE_FLAG_IRQS_NOSUPPORT | | |
895 | #endif | |
bc0c38d1 SR |
896 | ((pc & HARDIRQ_MASK) ? TRACE_FLAG_HARDIRQ : 0) | |
897 | ((pc & SOFTIRQ_MASK) ? TRACE_FLAG_SOFTIRQ : 0) | | |
898 | (need_resched() ? TRACE_FLAG_NEED_RESCHED : 0); | |
899 | } | |
f413cdb8 | 900 | EXPORT_SYMBOL_GPL(tracing_generic_entry_update); |
bc0c38d1 | 901 | |
e77405ad SR |
902 | struct ring_buffer_event * |
903 | trace_buffer_lock_reserve(struct ring_buffer *buffer, | |
904 | int type, | |
905 | unsigned long len, | |
906 | unsigned long flags, int pc) | |
51a763dd ACM |
907 | { |
908 | struct ring_buffer_event *event; | |
909 | ||
e77405ad | 910 | event = ring_buffer_lock_reserve(buffer, len); |
51a763dd ACM |
911 | if (event != NULL) { |
912 | struct trace_entry *ent = ring_buffer_event_data(event); | |
913 | ||
914 | tracing_generic_entry_update(ent, flags, pc); | |
915 | ent->type = type; | |
916 | } | |
917 | ||
918 | return event; | |
919 | } | |
51a763dd | 920 | |
e77405ad SR |
921 | static inline void |
922 | __trace_buffer_unlock_commit(struct ring_buffer *buffer, | |
923 | struct ring_buffer_event *event, | |
924 | unsigned long flags, int pc, | |
925 | int wake) | |
51a763dd | 926 | { |
e77405ad | 927 | ring_buffer_unlock_commit(buffer, event); |
51a763dd | 928 | |
e77405ad SR |
929 | ftrace_trace_stack(buffer, flags, 6, pc); |
930 | ftrace_trace_userstack(buffer, flags, pc); | |
07edf712 FW |
931 | |
932 | if (wake) | |
933 | trace_wake_up(); | |
934 | } | |
935 | ||
e77405ad SR |
936 | void trace_buffer_unlock_commit(struct ring_buffer *buffer, |
937 | struct ring_buffer_event *event, | |
938 | unsigned long flags, int pc) | |
07edf712 | 939 | { |
e77405ad | 940 | __trace_buffer_unlock_commit(buffer, event, flags, pc, 1); |
51a763dd ACM |
941 | } |
942 | ||
ef5580d0 | 943 | struct ring_buffer_event * |
e77405ad SR |
944 | trace_current_buffer_lock_reserve(struct ring_buffer **current_rb, |
945 | int type, unsigned long len, | |
ef5580d0 SR |
946 | unsigned long flags, int pc) |
947 | { | |
e77405ad SR |
948 | *current_rb = global_trace.buffer; |
949 | return trace_buffer_lock_reserve(*current_rb, | |
ef5580d0 SR |
950 | type, len, flags, pc); |
951 | } | |
94487d6d | 952 | EXPORT_SYMBOL_GPL(trace_current_buffer_lock_reserve); |
ef5580d0 | 953 | |
e77405ad SR |
954 | void trace_current_buffer_unlock_commit(struct ring_buffer *buffer, |
955 | struct ring_buffer_event *event, | |
ef5580d0 SR |
956 | unsigned long flags, int pc) |
957 | { | |
e77405ad | 958 | __trace_buffer_unlock_commit(buffer, event, flags, pc, 1); |
07edf712 | 959 | } |
94487d6d | 960 | EXPORT_SYMBOL_GPL(trace_current_buffer_unlock_commit); |
07edf712 | 961 | |
e77405ad SR |
962 | void trace_nowake_buffer_unlock_commit(struct ring_buffer *buffer, |
963 | struct ring_buffer_event *event, | |
964 | unsigned long flags, int pc) | |
07edf712 | 965 | { |
e77405ad | 966 | __trace_buffer_unlock_commit(buffer, event, flags, pc, 0); |
77d9f465 | 967 | } |
94487d6d | 968 | EXPORT_SYMBOL_GPL(trace_nowake_buffer_unlock_commit); |
77d9f465 | 969 | |
e77405ad SR |
970 | void trace_current_buffer_discard_commit(struct ring_buffer *buffer, |
971 | struct ring_buffer_event *event) | |
77d9f465 | 972 | { |
e77405ad | 973 | ring_buffer_discard_commit(buffer, event); |
ef5580d0 | 974 | } |
12acd473 | 975 | EXPORT_SYMBOL_GPL(trace_current_buffer_discard_commit); |
ef5580d0 | 976 | |
e309b41d | 977 | void |
7be42151 | 978 | trace_function(struct trace_array *tr, |
38697053 SR |
979 | unsigned long ip, unsigned long parent_ip, unsigned long flags, |
980 | int pc) | |
bc0c38d1 | 981 | { |
e1112b4d | 982 | struct ftrace_event_call *call = &event_function; |
e77405ad | 983 | struct ring_buffer *buffer = tr->buffer; |
3928a8a2 | 984 | struct ring_buffer_event *event; |
777e208d | 985 | struct ftrace_entry *entry; |
bc0c38d1 | 986 | |
d769041f SR |
987 | /* If we are reading the ring buffer, don't trace */ |
988 | if (unlikely(local_read(&__get_cpu_var(ftrace_cpu_disabled)))) | |
989 | return; | |
990 | ||
e77405ad | 991 | event = trace_buffer_lock_reserve(buffer, TRACE_FN, sizeof(*entry), |
51a763dd | 992 | flags, pc); |
3928a8a2 SR |
993 | if (!event) |
994 | return; | |
995 | entry = ring_buffer_event_data(event); | |
777e208d SR |
996 | entry->ip = ip; |
997 | entry->parent_ip = parent_ip; | |
e1112b4d | 998 | |
e77405ad SR |
999 | if (!filter_check_discard(call, entry, buffer, event)) |
1000 | ring_buffer_unlock_commit(buffer, event); | |
bc0c38d1 SR |
1001 | } |
1002 | ||
e309b41d | 1003 | void |
2e0f5761 | 1004 | ftrace(struct trace_array *tr, struct trace_array_cpu *data, |
38697053 SR |
1005 | unsigned long ip, unsigned long parent_ip, unsigned long flags, |
1006 | int pc) | |
2e0f5761 IM |
1007 | { |
1008 | if (likely(!atomic_read(&data->disabled))) | |
7be42151 | 1009 | trace_function(tr, ip, parent_ip, flags, pc); |
2e0f5761 IM |
1010 | } |
1011 | ||
c0a0d0d3 | 1012 | #ifdef CONFIG_STACKTRACE |
e77405ad | 1013 | static void __ftrace_trace_stack(struct ring_buffer *buffer, |
53614991 SR |
1014 | unsigned long flags, |
1015 | int skip, int pc) | |
86387f7e | 1016 | { |
e1112b4d | 1017 | struct ftrace_event_call *call = &event_kernel_stack; |
3928a8a2 | 1018 | struct ring_buffer_event *event; |
777e208d | 1019 | struct stack_entry *entry; |
86387f7e IM |
1020 | struct stack_trace trace; |
1021 | ||
e77405ad | 1022 | event = trace_buffer_lock_reserve(buffer, TRACE_STACK, |
51a763dd | 1023 | sizeof(*entry), flags, pc); |
3928a8a2 SR |
1024 | if (!event) |
1025 | return; | |
1026 | entry = ring_buffer_event_data(event); | |
777e208d | 1027 | memset(&entry->caller, 0, sizeof(entry->caller)); |
86387f7e IM |
1028 | |
1029 | trace.nr_entries = 0; | |
1030 | trace.max_entries = FTRACE_STACK_ENTRIES; | |
1031 | trace.skip = skip; | |
777e208d | 1032 | trace.entries = entry->caller; |
86387f7e IM |
1033 | |
1034 | save_stack_trace(&trace); | |
e77405ad SR |
1035 | if (!filter_check_discard(call, entry, buffer, event)) |
1036 | ring_buffer_unlock_commit(buffer, event); | |
f0a920d5 IM |
1037 | } |
1038 | ||
e77405ad SR |
1039 | void ftrace_trace_stack(struct ring_buffer *buffer, unsigned long flags, |
1040 | int skip, int pc) | |
53614991 SR |
1041 | { |
1042 | if (!(trace_flags & TRACE_ITER_STACKTRACE)) | |
1043 | return; | |
1044 | ||
e77405ad | 1045 | __ftrace_trace_stack(buffer, flags, skip, pc); |
53614991 SR |
1046 | } |
1047 | ||
c0a0d0d3 FW |
1048 | void __trace_stack(struct trace_array *tr, unsigned long flags, int skip, |
1049 | int pc) | |
38697053 | 1050 | { |
e77405ad | 1051 | __ftrace_trace_stack(tr->buffer, flags, skip, pc); |
38697053 SR |
1052 | } |
1053 | ||
e77405ad SR |
1054 | void |
1055 | ftrace_trace_userstack(struct ring_buffer *buffer, unsigned long flags, int pc) | |
02b67518 | 1056 | { |
e1112b4d | 1057 | struct ftrace_event_call *call = &event_user_stack; |
8d7c6a96 | 1058 | struct ring_buffer_event *event; |
02b67518 TE |
1059 | struct userstack_entry *entry; |
1060 | struct stack_trace trace; | |
02b67518 TE |
1061 | |
1062 | if (!(trace_flags & TRACE_ITER_USERSTACKTRACE)) | |
1063 | return; | |
1064 | ||
e77405ad | 1065 | event = trace_buffer_lock_reserve(buffer, TRACE_USER_STACK, |
51a763dd | 1066 | sizeof(*entry), flags, pc); |
02b67518 TE |
1067 | if (!event) |
1068 | return; | |
1069 | entry = ring_buffer_event_data(event); | |
02b67518 TE |
1070 | |
1071 | memset(&entry->caller, 0, sizeof(entry->caller)); | |
1072 | ||
1073 | trace.nr_entries = 0; | |
1074 | trace.max_entries = FTRACE_STACK_ENTRIES; | |
1075 | trace.skip = 0; | |
1076 | trace.entries = entry->caller; | |
1077 | ||
1078 | save_stack_trace_user(&trace); | |
e77405ad SR |
1079 | if (!filter_check_discard(call, entry, buffer, event)) |
1080 | ring_buffer_unlock_commit(buffer, event); | |
02b67518 TE |
1081 | } |
1082 | ||
4fd27358 HE |
1083 | #ifdef UNUSED |
1084 | static void __trace_userstack(struct trace_array *tr, unsigned long flags) | |
02b67518 | 1085 | { |
7be42151 | 1086 | ftrace_trace_userstack(tr, flags, preempt_count()); |
02b67518 | 1087 | } |
4fd27358 | 1088 | #endif /* UNUSED */ |
02b67518 | 1089 | |
c0a0d0d3 FW |
1090 | #endif /* CONFIG_STACKTRACE */ |
1091 | ||
38697053 | 1092 | static void |
7be42151 | 1093 | ftrace_trace_special(void *__tr, |
38697053 SR |
1094 | unsigned long arg1, unsigned long arg2, unsigned long arg3, |
1095 | int pc) | |
a4feb834 | 1096 | { |
3928a8a2 | 1097 | struct ring_buffer_event *event; |
a4feb834 | 1098 | struct trace_array *tr = __tr; |
e77405ad | 1099 | struct ring_buffer *buffer = tr->buffer; |
777e208d | 1100 | struct special_entry *entry; |
a4feb834 | 1101 | |
e77405ad | 1102 | event = trace_buffer_lock_reserve(buffer, TRACE_SPECIAL, |
51a763dd | 1103 | sizeof(*entry), 0, pc); |
3928a8a2 SR |
1104 | if (!event) |
1105 | return; | |
1106 | entry = ring_buffer_event_data(event); | |
777e208d SR |
1107 | entry->arg1 = arg1; |
1108 | entry->arg2 = arg2; | |
1109 | entry->arg3 = arg3; | |
e77405ad | 1110 | trace_buffer_unlock_commit(buffer, event, 0, pc); |
a4feb834 IM |
1111 | } |
1112 | ||
38697053 SR |
1113 | void |
1114 | __trace_special(void *__tr, void *__data, | |
1115 | unsigned long arg1, unsigned long arg2, unsigned long arg3) | |
1116 | { | |
7be42151 | 1117 | ftrace_trace_special(__tr, arg1, arg2, arg3, preempt_count()); |
38697053 SR |
1118 | } |
1119 | ||
4902f884 SR |
1120 | void |
1121 | ftrace_special(unsigned long arg1, unsigned long arg2, unsigned long arg3) | |
1122 | { | |
1123 | struct trace_array *tr = &global_trace; | |
1124 | struct trace_array_cpu *data; | |
5aa1ba6a | 1125 | unsigned long flags; |
4902f884 | 1126 | int cpu; |
38697053 | 1127 | int pc; |
4902f884 | 1128 | |
c76f0694 | 1129 | if (tracing_disabled) |
4902f884 SR |
1130 | return; |
1131 | ||
38697053 | 1132 | pc = preempt_count(); |
5aa1ba6a | 1133 | local_irq_save(flags); |
4902f884 SR |
1134 | cpu = raw_smp_processor_id(); |
1135 | data = tr->data[cpu]; | |
4902f884 | 1136 | |
5aa1ba6a | 1137 | if (likely(atomic_inc_return(&data->disabled) == 1)) |
7be42151 | 1138 | ftrace_trace_special(tr, arg1, arg2, arg3, pc); |
4902f884 | 1139 | |
5aa1ba6a SR |
1140 | atomic_dec(&data->disabled); |
1141 | local_irq_restore(flags); | |
4902f884 SR |
1142 | } |
1143 | ||
769b0441 | 1144 | /** |
48ead020 | 1145 | * trace_vbprintk - write binary msg to tracing buffer |
769b0441 FW |
1146 | * |
1147 | */ | |
40ce74f1 | 1148 | int trace_vbprintk(unsigned long ip, const char *fmt, va_list args) |
769b0441 | 1149 | { |
80370cb7 SR |
1150 | static raw_spinlock_t trace_buf_lock = |
1151 | (raw_spinlock_t)__RAW_SPIN_LOCK_UNLOCKED; | |
769b0441 FW |
1152 | static u32 trace_buf[TRACE_BUF_SIZE]; |
1153 | ||
e1112b4d | 1154 | struct ftrace_event_call *call = &event_bprint; |
769b0441 | 1155 | struct ring_buffer_event *event; |
e77405ad | 1156 | struct ring_buffer *buffer; |
769b0441 FW |
1157 | struct trace_array *tr = &global_trace; |
1158 | struct trace_array_cpu *data; | |
48ead020 | 1159 | struct bprint_entry *entry; |
769b0441 | 1160 | unsigned long flags; |
3189cdb3 | 1161 | int disable; |
769b0441 FW |
1162 | int resched; |
1163 | int cpu, len = 0, size, pc; | |
1164 | ||
1165 | if (unlikely(tracing_selftest_running || tracing_disabled)) | |
1166 | return 0; | |
1167 | ||
1168 | /* Don't pollute graph traces with trace_vprintk internals */ | |
1169 | pause_graph_tracing(); | |
1170 | ||
1171 | pc = preempt_count(); | |
1172 | resched = ftrace_preempt_disable(); | |
1173 | cpu = raw_smp_processor_id(); | |
1174 | data = tr->data[cpu]; | |
1175 | ||
3189cdb3 SR |
1176 | disable = atomic_inc_return(&data->disabled); |
1177 | if (unlikely(disable != 1)) | |
769b0441 FW |
1178 | goto out; |
1179 | ||
80370cb7 SR |
1180 | /* Lockdep uses trace_printk for lock tracing */ |
1181 | local_irq_save(flags); | |
1182 | __raw_spin_lock(&trace_buf_lock); | |
769b0441 FW |
1183 | len = vbin_printf(trace_buf, TRACE_BUF_SIZE, fmt, args); |
1184 | ||
1185 | if (len > TRACE_BUF_SIZE || len < 0) | |
1186 | goto out_unlock; | |
1187 | ||
1188 | size = sizeof(*entry) + sizeof(u32) * len; | |
e77405ad SR |
1189 | buffer = tr->buffer; |
1190 | event = trace_buffer_lock_reserve(buffer, TRACE_BPRINT, size, | |
1191 | flags, pc); | |
769b0441 FW |
1192 | if (!event) |
1193 | goto out_unlock; | |
1194 | entry = ring_buffer_event_data(event); | |
1195 | entry->ip = ip; | |
769b0441 FW |
1196 | entry->fmt = fmt; |
1197 | ||
1198 | memcpy(entry->buf, trace_buf, sizeof(u32) * len); | |
e77405ad SR |
1199 | if (!filter_check_discard(call, entry, buffer, event)) |
1200 | ring_buffer_unlock_commit(buffer, event); | |
769b0441 FW |
1201 | |
1202 | out_unlock: | |
80370cb7 SR |
1203 | __raw_spin_unlock(&trace_buf_lock); |
1204 | local_irq_restore(flags); | |
769b0441 FW |
1205 | |
1206 | out: | |
3189cdb3 | 1207 | atomic_dec_return(&data->disabled); |
769b0441 FW |
1208 | ftrace_preempt_enable(resched); |
1209 | unpause_graph_tracing(); | |
1210 | ||
1211 | return len; | |
1212 | } | |
48ead020 FW |
1213 | EXPORT_SYMBOL_GPL(trace_vbprintk); |
1214 | ||
659372d3 SR |
1215 | int trace_array_printk(struct trace_array *tr, |
1216 | unsigned long ip, const char *fmt, ...) | |
1217 | { | |
1218 | int ret; | |
1219 | va_list ap; | |
1220 | ||
1221 | if (!(trace_flags & TRACE_ITER_PRINTK)) | |
1222 | return 0; | |
1223 | ||
1224 | va_start(ap, fmt); | |
1225 | ret = trace_array_vprintk(tr, ip, fmt, ap); | |
1226 | va_end(ap); | |
1227 | return ret; | |
1228 | } | |
1229 | ||
1230 | int trace_array_vprintk(struct trace_array *tr, | |
1231 | unsigned long ip, const char *fmt, va_list args) | |
48ead020 FW |
1232 | { |
1233 | static raw_spinlock_t trace_buf_lock = __RAW_SPIN_LOCK_UNLOCKED; | |
1234 | static char trace_buf[TRACE_BUF_SIZE]; | |
1235 | ||
e1112b4d | 1236 | struct ftrace_event_call *call = &event_print; |
48ead020 | 1237 | struct ring_buffer_event *event; |
e77405ad | 1238 | struct ring_buffer *buffer; |
48ead020 FW |
1239 | struct trace_array_cpu *data; |
1240 | int cpu, len = 0, size, pc; | |
1241 | struct print_entry *entry; | |
1242 | unsigned long irq_flags; | |
3189cdb3 | 1243 | int disable; |
48ead020 FW |
1244 | |
1245 | if (tracing_disabled || tracing_selftest_running) | |
1246 | return 0; | |
1247 | ||
1248 | pc = preempt_count(); | |
1249 | preempt_disable_notrace(); | |
1250 | cpu = raw_smp_processor_id(); | |
1251 | data = tr->data[cpu]; | |
1252 | ||
3189cdb3 SR |
1253 | disable = atomic_inc_return(&data->disabled); |
1254 | if (unlikely(disable != 1)) | |
48ead020 FW |
1255 | goto out; |
1256 | ||
1257 | pause_graph_tracing(); | |
1258 | raw_local_irq_save(irq_flags); | |
1259 | __raw_spin_lock(&trace_buf_lock); | |
1260 | len = vsnprintf(trace_buf, TRACE_BUF_SIZE, fmt, args); | |
1261 | ||
1262 | len = min(len, TRACE_BUF_SIZE-1); | |
1263 | trace_buf[len] = 0; | |
1264 | ||
1265 | size = sizeof(*entry) + len + 1; | |
e77405ad SR |
1266 | buffer = tr->buffer; |
1267 | event = trace_buffer_lock_reserve(buffer, TRACE_PRINT, size, | |
1268 | irq_flags, pc); | |
48ead020 FW |
1269 | if (!event) |
1270 | goto out_unlock; | |
1271 | entry = ring_buffer_event_data(event); | |
1272 | entry->ip = ip; | |
48ead020 FW |
1273 | |
1274 | memcpy(&entry->buf, trace_buf, len); | |
1275 | entry->buf[len] = 0; | |
e77405ad SR |
1276 | if (!filter_check_discard(call, entry, buffer, event)) |
1277 | ring_buffer_unlock_commit(buffer, event); | |
48ead020 FW |
1278 | |
1279 | out_unlock: | |
1280 | __raw_spin_unlock(&trace_buf_lock); | |
1281 | raw_local_irq_restore(irq_flags); | |
1282 | unpause_graph_tracing(); | |
1283 | out: | |
3189cdb3 | 1284 | atomic_dec_return(&data->disabled); |
48ead020 FW |
1285 | preempt_enable_notrace(); |
1286 | ||
1287 | return len; | |
1288 | } | |
659372d3 SR |
1289 | |
1290 | int trace_vprintk(unsigned long ip, const char *fmt, va_list args) | |
1291 | { | |
1292 | return trace_array_printk(&global_trace, ip, fmt, args); | |
1293 | } | |
769b0441 FW |
1294 | EXPORT_SYMBOL_GPL(trace_vprintk); |
1295 | ||
bc0c38d1 SR |
1296 | enum trace_file_type { |
1297 | TRACE_FILE_LAT_FMT = 1, | |
12ef7d44 | 1298 | TRACE_FILE_ANNOTATE = 2, |
bc0c38d1 SR |
1299 | }; |
1300 | ||
e2ac8ef5 | 1301 | static void trace_iterator_increment(struct trace_iterator *iter) |
5a90f577 | 1302 | { |
d769041f SR |
1303 | /* Don't allow ftrace to trace into the ring buffers */ |
1304 | ftrace_disable_cpu(); | |
1305 | ||
5a90f577 | 1306 | iter->idx++; |
d769041f SR |
1307 | if (iter->buffer_iter[iter->cpu]) |
1308 | ring_buffer_read(iter->buffer_iter[iter->cpu], NULL); | |
1309 | ||
1310 | ftrace_enable_cpu(); | |
5a90f577 SR |
1311 | } |
1312 | ||
e309b41d | 1313 | static struct trace_entry * |
3928a8a2 | 1314 | peek_next_entry(struct trace_iterator *iter, int cpu, u64 *ts) |
dd0e545f | 1315 | { |
3928a8a2 SR |
1316 | struct ring_buffer_event *event; |
1317 | struct ring_buffer_iter *buf_iter = iter->buffer_iter[cpu]; | |
dd0e545f | 1318 | |
d769041f SR |
1319 | /* Don't allow ftrace to trace into the ring buffers */ |
1320 | ftrace_disable_cpu(); | |
1321 | ||
1322 | if (buf_iter) | |
1323 | event = ring_buffer_iter_peek(buf_iter, ts); | |
1324 | else | |
1325 | event = ring_buffer_peek(iter->tr->buffer, cpu, ts); | |
1326 | ||
1327 | ftrace_enable_cpu(); | |
1328 | ||
3928a8a2 | 1329 | return event ? ring_buffer_event_data(event) : NULL; |
dd0e545f | 1330 | } |
d769041f | 1331 | |
dd0e545f | 1332 | static struct trace_entry * |
3928a8a2 | 1333 | __find_next_entry(struct trace_iterator *iter, int *ent_cpu, u64 *ent_ts) |
bc0c38d1 | 1334 | { |
3928a8a2 | 1335 | struct ring_buffer *buffer = iter->tr->buffer; |
bc0c38d1 | 1336 | struct trace_entry *ent, *next = NULL; |
b04cc6b1 | 1337 | int cpu_file = iter->cpu_file; |
3928a8a2 | 1338 | u64 next_ts = 0, ts; |
bc0c38d1 SR |
1339 | int next_cpu = -1; |
1340 | int cpu; | |
1341 | ||
b04cc6b1 FW |
1342 | /* |
1343 | * If we are in a per_cpu trace file, don't bother by iterating over | |
1344 | * all cpu and peek directly. | |
1345 | */ | |
1346 | if (cpu_file > TRACE_PIPE_ALL_CPU) { | |
1347 | if (ring_buffer_empty_cpu(buffer, cpu_file)) | |
1348 | return NULL; | |
1349 | ent = peek_next_entry(iter, cpu_file, ent_ts); | |
1350 | if (ent_cpu) | |
1351 | *ent_cpu = cpu_file; | |
1352 | ||
1353 | return ent; | |
1354 | } | |
1355 | ||
ab46428c | 1356 | for_each_tracing_cpu(cpu) { |
dd0e545f | 1357 | |
3928a8a2 SR |
1358 | if (ring_buffer_empty_cpu(buffer, cpu)) |
1359 | continue; | |
dd0e545f | 1360 | |
3928a8a2 | 1361 | ent = peek_next_entry(iter, cpu, &ts); |
dd0e545f | 1362 | |
cdd31cd2 IM |
1363 | /* |
1364 | * Pick the entry with the smallest timestamp: | |
1365 | */ | |
3928a8a2 | 1366 | if (ent && (!next || ts < next_ts)) { |
bc0c38d1 SR |
1367 | next = ent; |
1368 | next_cpu = cpu; | |
3928a8a2 | 1369 | next_ts = ts; |
bc0c38d1 SR |
1370 | } |
1371 | } | |
1372 | ||
1373 | if (ent_cpu) | |
1374 | *ent_cpu = next_cpu; | |
1375 | ||
3928a8a2 SR |
1376 | if (ent_ts) |
1377 | *ent_ts = next_ts; | |
1378 | ||
bc0c38d1 SR |
1379 | return next; |
1380 | } | |
1381 | ||
dd0e545f | 1382 | /* Find the next real entry, without updating the iterator itself */ |
c4a8e8be FW |
1383 | struct trace_entry *trace_find_next_entry(struct trace_iterator *iter, |
1384 | int *ent_cpu, u64 *ent_ts) | |
bc0c38d1 | 1385 | { |
3928a8a2 | 1386 | return __find_next_entry(iter, ent_cpu, ent_ts); |
dd0e545f SR |
1387 | } |
1388 | ||
1389 | /* Find the next real entry, and increment the iterator to the next entry */ | |
1390 | static void *find_next_entry_inc(struct trace_iterator *iter) | |
1391 | { | |
3928a8a2 | 1392 | iter->ent = __find_next_entry(iter, &iter->cpu, &iter->ts); |
dd0e545f | 1393 | |
3928a8a2 | 1394 | if (iter->ent) |
e2ac8ef5 | 1395 | trace_iterator_increment(iter); |
dd0e545f | 1396 | |
3928a8a2 | 1397 | return iter->ent ? iter : NULL; |
b3806b43 | 1398 | } |
bc0c38d1 | 1399 | |
e309b41d | 1400 | static void trace_consume(struct trace_iterator *iter) |
b3806b43 | 1401 | { |
d769041f SR |
1402 | /* Don't allow ftrace to trace into the ring buffers */ |
1403 | ftrace_disable_cpu(); | |
3928a8a2 | 1404 | ring_buffer_consume(iter->tr->buffer, iter->cpu, &iter->ts); |
d769041f | 1405 | ftrace_enable_cpu(); |
bc0c38d1 SR |
1406 | } |
1407 | ||
e309b41d | 1408 | static void *s_next(struct seq_file *m, void *v, loff_t *pos) |
bc0c38d1 SR |
1409 | { |
1410 | struct trace_iterator *iter = m->private; | |
bc0c38d1 | 1411 | int i = (int)*pos; |
4e3c3333 | 1412 | void *ent; |
bc0c38d1 SR |
1413 | |
1414 | (*pos)++; | |
1415 | ||
1416 | /* can't go backwards */ | |
1417 | if (iter->idx > i) | |
1418 | return NULL; | |
1419 | ||
1420 | if (iter->idx < 0) | |
1421 | ent = find_next_entry_inc(iter); | |
1422 | else | |
1423 | ent = iter; | |
1424 | ||
1425 | while (ent && iter->idx < i) | |
1426 | ent = find_next_entry_inc(iter); | |
1427 | ||
1428 | iter->pos = *pos; | |
1429 | ||
bc0c38d1 SR |
1430 | return ent; |
1431 | } | |
1432 | ||
2f26ebd5 SR |
1433 | static void tracing_iter_reset(struct trace_iterator *iter, int cpu) |
1434 | { | |
1435 | struct trace_array *tr = iter->tr; | |
1436 | struct ring_buffer_event *event; | |
1437 | struct ring_buffer_iter *buf_iter; | |
1438 | unsigned long entries = 0; | |
1439 | u64 ts; | |
1440 | ||
1441 | tr->data[cpu]->skipped_entries = 0; | |
1442 | ||
1443 | if (!iter->buffer_iter[cpu]) | |
1444 | return; | |
1445 | ||
1446 | buf_iter = iter->buffer_iter[cpu]; | |
1447 | ring_buffer_iter_reset(buf_iter); | |
1448 | ||
1449 | /* | |
1450 | * We could have the case with the max latency tracers | |
1451 | * that a reset never took place on a cpu. This is evident | |
1452 | * by the timestamp being before the start of the buffer. | |
1453 | */ | |
1454 | while ((event = ring_buffer_iter_peek(buf_iter, &ts))) { | |
1455 | if (ts >= iter->tr->time_start) | |
1456 | break; | |
1457 | entries++; | |
1458 | ring_buffer_read(buf_iter, NULL); | |
1459 | } | |
1460 | ||
1461 | tr->data[cpu]->skipped_entries = entries; | |
1462 | } | |
1463 | ||
d7350c3f FW |
1464 | /* |
1465 | * No necessary locking here. The worst thing which can | |
1466 | * happen is loosing events consumed at the same time | |
1467 | * by a trace_pipe reader. | |
1468 | * Other than that, we don't risk to crash the ring buffer | |
1469 | * because it serializes the readers. | |
1470 | * | |
1471 | * The current tracer is copied to avoid a global locking | |
1472 | * all around. | |
1473 | */ | |
bc0c38d1 SR |
1474 | static void *s_start(struct seq_file *m, loff_t *pos) |
1475 | { | |
1476 | struct trace_iterator *iter = m->private; | |
d7350c3f | 1477 | static struct tracer *old_tracer; |
b04cc6b1 | 1478 | int cpu_file = iter->cpu_file; |
bc0c38d1 SR |
1479 | void *p = NULL; |
1480 | loff_t l = 0; | |
3928a8a2 | 1481 | int cpu; |
bc0c38d1 | 1482 | |
d7350c3f | 1483 | /* copy the tracer to avoid using a global lock all around */ |
bc0c38d1 | 1484 | mutex_lock(&trace_types_lock); |
d7350c3f FW |
1485 | if (unlikely(old_tracer != current_trace && current_trace)) { |
1486 | old_tracer = current_trace; | |
1487 | *iter->trace = *current_trace; | |
d15f57f2 | 1488 | } |
d7350c3f | 1489 | mutex_unlock(&trace_types_lock); |
bc0c38d1 SR |
1490 | |
1491 | atomic_inc(&trace_record_cmdline_disabled); | |
1492 | ||
bc0c38d1 SR |
1493 | if (*pos != iter->pos) { |
1494 | iter->ent = NULL; | |
1495 | iter->cpu = 0; | |
1496 | iter->idx = -1; | |
1497 | ||
d769041f SR |
1498 | ftrace_disable_cpu(); |
1499 | ||
b04cc6b1 FW |
1500 | if (cpu_file == TRACE_PIPE_ALL_CPU) { |
1501 | for_each_tracing_cpu(cpu) | |
2f26ebd5 | 1502 | tracing_iter_reset(iter, cpu); |
b04cc6b1 | 1503 | } else |
2f26ebd5 | 1504 | tracing_iter_reset(iter, cpu_file); |
bc0c38d1 | 1505 | |
d769041f SR |
1506 | ftrace_enable_cpu(); |
1507 | ||
bc0c38d1 SR |
1508 | for (p = iter; p && l < *pos; p = s_next(m, p, &l)) |
1509 | ; | |
1510 | ||
1511 | } else { | |
4c11d7ae | 1512 | l = *pos - 1; |
bc0c38d1 SR |
1513 | p = s_next(m, p, &l); |
1514 | } | |
1515 | ||
4f535968 | 1516 | trace_event_read_lock(); |
bc0c38d1 SR |
1517 | return p; |
1518 | } | |
1519 | ||
1520 | static void s_stop(struct seq_file *m, void *p) | |
1521 | { | |
bc0c38d1 | 1522 | atomic_dec(&trace_record_cmdline_disabled); |
4f535968 | 1523 | trace_event_read_unlock(); |
bc0c38d1 SR |
1524 | } |
1525 | ||
e309b41d | 1526 | static void print_lat_help_header(struct seq_file *m) |
bc0c38d1 | 1527 | { |
a6168353 ME |
1528 | seq_puts(m, "# _------=> CPU# \n"); |
1529 | seq_puts(m, "# / _-----=> irqs-off \n"); | |
1530 | seq_puts(m, "# | / _----=> need-resched \n"); | |
1531 | seq_puts(m, "# || / _---=> hardirq/softirq \n"); | |
1532 | seq_puts(m, "# ||| / _--=> preempt-depth \n"); | |
1533 | seq_puts(m, "# |||| / \n"); | |
1534 | seq_puts(m, "# ||||| delay \n"); | |
1535 | seq_puts(m, "# cmd pid ||||| time | caller \n"); | |
1536 | seq_puts(m, "# \\ / ||||| \\ | / \n"); | |
bc0c38d1 SR |
1537 | } |
1538 | ||
e309b41d | 1539 | static void print_func_help_header(struct seq_file *m) |
bc0c38d1 | 1540 | { |
a6168353 ME |
1541 | seq_puts(m, "# TASK-PID CPU# TIMESTAMP FUNCTION\n"); |
1542 | seq_puts(m, "# | | | | |\n"); | |
bc0c38d1 SR |
1543 | } |
1544 | ||
1545 | ||
e309b41d | 1546 | static void |
bc0c38d1 SR |
1547 | print_trace_header(struct seq_file *m, struct trace_iterator *iter) |
1548 | { | |
1549 | unsigned long sym_flags = (trace_flags & TRACE_ITER_SYM_MASK); | |
1550 | struct trace_array *tr = iter->tr; | |
1551 | struct trace_array_cpu *data = tr->data[tr->cpu]; | |
1552 | struct tracer *type = current_trace; | |
2f26ebd5 SR |
1553 | unsigned long entries = 0; |
1554 | unsigned long total = 0; | |
1555 | unsigned long count; | |
bc0c38d1 | 1556 | const char *name = "preemption"; |
2f26ebd5 | 1557 | int cpu; |
bc0c38d1 SR |
1558 | |
1559 | if (type) | |
1560 | name = type->name; | |
1561 | ||
2f26ebd5 SR |
1562 | |
1563 | for_each_tracing_cpu(cpu) { | |
1564 | count = ring_buffer_entries_cpu(tr->buffer, cpu); | |
1565 | /* | |
1566 | * If this buffer has skipped entries, then we hold all | |
1567 | * entries for the trace and we need to ignore the | |
1568 | * ones before the time stamp. | |
1569 | */ | |
1570 | if (tr->data[cpu]->skipped_entries) { | |
1571 | count -= tr->data[cpu]->skipped_entries; | |
1572 | /* total is the same as the entries */ | |
1573 | total += count; | |
1574 | } else | |
1575 | total += count + | |
1576 | ring_buffer_overrun_cpu(tr->buffer, cpu); | |
1577 | entries += count; | |
1578 | } | |
bc0c38d1 | 1579 | |
888b55dc | 1580 | seq_printf(m, "# %s latency trace v1.1.5 on %s\n", |
bc0c38d1 | 1581 | name, UTS_RELEASE); |
888b55dc | 1582 | seq_puts(m, "# -----------------------------------" |
bc0c38d1 | 1583 | "---------------------------------\n"); |
888b55dc | 1584 | seq_printf(m, "# latency: %lu us, #%lu/%lu, CPU#%d |" |
bc0c38d1 | 1585 | " (M:%s VP:%d, KP:%d, SP:%d HP:%d", |
57f50be1 | 1586 | nsecs_to_usecs(data->saved_latency), |
bc0c38d1 | 1587 | entries, |
4c11d7ae | 1588 | total, |
bc0c38d1 SR |
1589 | tr->cpu, |
1590 | #if defined(CONFIG_PREEMPT_NONE) | |
1591 | "server", | |
1592 | #elif defined(CONFIG_PREEMPT_VOLUNTARY) | |
1593 | "desktop", | |
b5c21b45 | 1594 | #elif defined(CONFIG_PREEMPT) |
bc0c38d1 SR |
1595 | "preempt", |
1596 | #else | |
1597 | "unknown", | |
1598 | #endif | |
1599 | /* These are reserved for later use */ | |
1600 | 0, 0, 0, 0); | |
1601 | #ifdef CONFIG_SMP | |
1602 | seq_printf(m, " #P:%d)\n", num_online_cpus()); | |
1603 | #else | |
1604 | seq_puts(m, ")\n"); | |
1605 | #endif | |
888b55dc KM |
1606 | seq_puts(m, "# -----------------\n"); |
1607 | seq_printf(m, "# | task: %.16s-%d " | |
bc0c38d1 SR |
1608 | "(uid:%d nice:%ld policy:%ld rt_prio:%ld)\n", |
1609 | data->comm, data->pid, data->uid, data->nice, | |
1610 | data->policy, data->rt_priority); | |
888b55dc | 1611 | seq_puts(m, "# -----------------\n"); |
bc0c38d1 SR |
1612 | |
1613 | if (data->critical_start) { | |
888b55dc | 1614 | seq_puts(m, "# => started at: "); |
214023c3 SR |
1615 | seq_print_ip_sym(&iter->seq, data->critical_start, sym_flags); |
1616 | trace_print_seq(m, &iter->seq); | |
888b55dc | 1617 | seq_puts(m, "\n# => ended at: "); |
214023c3 SR |
1618 | seq_print_ip_sym(&iter->seq, data->critical_end, sym_flags); |
1619 | trace_print_seq(m, &iter->seq); | |
8248ac05 | 1620 | seq_puts(m, "\n#\n"); |
bc0c38d1 SR |
1621 | } |
1622 | ||
888b55dc | 1623 | seq_puts(m, "#\n"); |
bc0c38d1 SR |
1624 | } |
1625 | ||
a309720c SR |
1626 | static void test_cpu_buff_start(struct trace_iterator *iter) |
1627 | { | |
1628 | struct trace_seq *s = &iter->seq; | |
1629 | ||
12ef7d44 SR |
1630 | if (!(trace_flags & TRACE_ITER_ANNOTATE)) |
1631 | return; | |
1632 | ||
1633 | if (!(iter->iter_flags & TRACE_FILE_ANNOTATE)) | |
1634 | return; | |
1635 | ||
4462344e | 1636 | if (cpumask_test_cpu(iter->cpu, iter->started)) |
a309720c SR |
1637 | return; |
1638 | ||
2f26ebd5 SR |
1639 | if (iter->tr->data[iter->cpu]->skipped_entries) |
1640 | return; | |
1641 | ||
4462344e | 1642 | cpumask_set_cpu(iter->cpu, iter->started); |
b0dfa978 FW |
1643 | |
1644 | /* Don't print started cpu buffer for the first entry of the trace */ | |
1645 | if (iter->idx > 1) | |
1646 | trace_seq_printf(s, "##### CPU %u buffer started ####\n", | |
1647 | iter->cpu); | |
a309720c SR |
1648 | } |
1649 | ||
2c4f035f | 1650 | static enum print_line_t print_trace_fmt(struct trace_iterator *iter) |
bc0c38d1 | 1651 | { |
214023c3 | 1652 | struct trace_seq *s = &iter->seq; |
bc0c38d1 | 1653 | unsigned long sym_flags = (trace_flags & TRACE_ITER_SYM_MASK); |
4e3c3333 | 1654 | struct trace_entry *entry; |
f633cef0 | 1655 | struct trace_event *event; |
bc0c38d1 | 1656 | |
4e3c3333 | 1657 | entry = iter->ent; |
dd0e545f | 1658 | |
a309720c SR |
1659 | test_cpu_buff_start(iter); |
1660 | ||
c4a8e8be | 1661 | event = ftrace_find_event(entry->type); |
bc0c38d1 | 1662 | |
c4a8e8be | 1663 | if (trace_flags & TRACE_ITER_CONTEXT_INFO) { |
27d48be8 SR |
1664 | if (iter->iter_flags & TRACE_FILE_LAT_FMT) { |
1665 | if (!trace_print_lat_context(iter)) | |
1666 | goto partial; | |
1667 | } else { | |
1668 | if (!trace_print_context(iter)) | |
1669 | goto partial; | |
1670 | } | |
c4a8e8be | 1671 | } |
bc0c38d1 | 1672 | |
268ccda0 | 1673 | if (event) |
d9793bd8 ACM |
1674 | return event->trace(iter, sym_flags); |
1675 | ||
1676 | if (!trace_seq_printf(s, "Unknown type %d\n", entry->type)) | |
1677 | goto partial; | |
02b67518 | 1678 | |
2c4f035f | 1679 | return TRACE_TYPE_HANDLED; |
d9793bd8 ACM |
1680 | partial: |
1681 | return TRACE_TYPE_PARTIAL_LINE; | |
bc0c38d1 SR |
1682 | } |
1683 | ||
2c4f035f | 1684 | static enum print_line_t print_raw_fmt(struct trace_iterator *iter) |
f9896bf3 IM |
1685 | { |
1686 | struct trace_seq *s = &iter->seq; | |
1687 | struct trace_entry *entry; | |
f633cef0 | 1688 | struct trace_event *event; |
f9896bf3 IM |
1689 | |
1690 | entry = iter->ent; | |
dd0e545f | 1691 | |
c4a8e8be | 1692 | if (trace_flags & TRACE_ITER_CONTEXT_INFO) { |
d9793bd8 ACM |
1693 | if (!trace_seq_printf(s, "%d %d %llu ", |
1694 | entry->pid, iter->cpu, iter->ts)) | |
1695 | goto partial; | |
c4a8e8be | 1696 | } |
f9896bf3 | 1697 | |
f633cef0 | 1698 | event = ftrace_find_event(entry->type); |
268ccda0 | 1699 | if (event) |
d9793bd8 ACM |
1700 | return event->raw(iter, 0); |
1701 | ||
1702 | if (!trace_seq_printf(s, "%d ?\n", entry->type)) | |
1703 | goto partial; | |
777e208d | 1704 | |
2c4f035f | 1705 | return TRACE_TYPE_HANDLED; |
d9793bd8 ACM |
1706 | partial: |
1707 | return TRACE_TYPE_PARTIAL_LINE; | |
f9896bf3 IM |
1708 | } |
1709 | ||
2c4f035f | 1710 | static enum print_line_t print_hex_fmt(struct trace_iterator *iter) |
5e3ca0ec IM |
1711 | { |
1712 | struct trace_seq *s = &iter->seq; | |
1713 | unsigned char newline = '\n'; | |
1714 | struct trace_entry *entry; | |
f633cef0 | 1715 | struct trace_event *event; |
5e3ca0ec IM |
1716 | |
1717 | entry = iter->ent; | |
dd0e545f | 1718 | |
c4a8e8be FW |
1719 | if (trace_flags & TRACE_ITER_CONTEXT_INFO) { |
1720 | SEQ_PUT_HEX_FIELD_RET(s, entry->pid); | |
1721 | SEQ_PUT_HEX_FIELD_RET(s, iter->cpu); | |
1722 | SEQ_PUT_HEX_FIELD_RET(s, iter->ts); | |
1723 | } | |
5e3ca0ec | 1724 | |
f633cef0 | 1725 | event = ftrace_find_event(entry->type); |
268ccda0 | 1726 | if (event) { |
ae7462b4 | 1727 | enum print_line_t ret = event->hex(iter, 0); |
d9793bd8 ACM |
1728 | if (ret != TRACE_TYPE_HANDLED) |
1729 | return ret; | |
1730 | } | |
7104f300 | 1731 | |
5e3ca0ec IM |
1732 | SEQ_PUT_FIELD_RET(s, newline); |
1733 | ||
2c4f035f | 1734 | return TRACE_TYPE_HANDLED; |
5e3ca0ec IM |
1735 | } |
1736 | ||
2c4f035f | 1737 | static enum print_line_t print_bin_fmt(struct trace_iterator *iter) |
cb0f12aa IM |
1738 | { |
1739 | struct trace_seq *s = &iter->seq; | |
1740 | struct trace_entry *entry; | |
f633cef0 | 1741 | struct trace_event *event; |
cb0f12aa IM |
1742 | |
1743 | entry = iter->ent; | |
dd0e545f | 1744 | |
c4a8e8be FW |
1745 | if (trace_flags & TRACE_ITER_CONTEXT_INFO) { |
1746 | SEQ_PUT_FIELD_RET(s, entry->pid); | |
1830b52d | 1747 | SEQ_PUT_FIELD_RET(s, iter->cpu); |
c4a8e8be FW |
1748 | SEQ_PUT_FIELD_RET(s, iter->ts); |
1749 | } | |
cb0f12aa | 1750 | |
f633cef0 | 1751 | event = ftrace_find_event(entry->type); |
268ccda0 | 1752 | return event ? event->binary(iter, 0) : TRACE_TYPE_HANDLED; |
cb0f12aa IM |
1753 | } |
1754 | ||
bc0c38d1 SR |
1755 | static int trace_empty(struct trace_iterator *iter) |
1756 | { | |
bc0c38d1 SR |
1757 | int cpu; |
1758 | ||
9aba60fe SR |
1759 | /* If we are looking at one CPU buffer, only check that one */ |
1760 | if (iter->cpu_file != TRACE_PIPE_ALL_CPU) { | |
1761 | cpu = iter->cpu_file; | |
1762 | if (iter->buffer_iter[cpu]) { | |
1763 | if (!ring_buffer_iter_empty(iter->buffer_iter[cpu])) | |
1764 | return 0; | |
1765 | } else { | |
1766 | if (!ring_buffer_empty_cpu(iter->tr->buffer, cpu)) | |
1767 | return 0; | |
1768 | } | |
1769 | return 1; | |
1770 | } | |
1771 | ||
ab46428c | 1772 | for_each_tracing_cpu(cpu) { |
d769041f SR |
1773 | if (iter->buffer_iter[cpu]) { |
1774 | if (!ring_buffer_iter_empty(iter->buffer_iter[cpu])) | |
1775 | return 0; | |
1776 | } else { | |
1777 | if (!ring_buffer_empty_cpu(iter->tr->buffer, cpu)) | |
1778 | return 0; | |
1779 | } | |
bc0c38d1 | 1780 | } |
d769041f | 1781 | |
797d3712 | 1782 | return 1; |
bc0c38d1 SR |
1783 | } |
1784 | ||
4f535968 | 1785 | /* Called with trace_event_read_lock() held. */ |
2c4f035f | 1786 | static enum print_line_t print_trace_line(struct trace_iterator *iter) |
f9896bf3 | 1787 | { |
2c4f035f FW |
1788 | enum print_line_t ret; |
1789 | ||
1790 | if (iter->trace && iter->trace->print_line) { | |
1791 | ret = iter->trace->print_line(iter); | |
1792 | if (ret != TRACE_TYPE_UNHANDLED) | |
1793 | return ret; | |
1794 | } | |
72829bc3 | 1795 | |
48ead020 FW |
1796 | if (iter->ent->type == TRACE_BPRINT && |
1797 | trace_flags & TRACE_ITER_PRINTK && | |
1798 | trace_flags & TRACE_ITER_PRINTK_MSGONLY) | |
5ef841f6 | 1799 | return trace_print_bprintk_msg_only(iter); |
48ead020 | 1800 | |
66896a85 FW |
1801 | if (iter->ent->type == TRACE_PRINT && |
1802 | trace_flags & TRACE_ITER_PRINTK && | |
1803 | trace_flags & TRACE_ITER_PRINTK_MSGONLY) | |
5ef841f6 | 1804 | return trace_print_printk_msg_only(iter); |
66896a85 | 1805 | |
cb0f12aa IM |
1806 | if (trace_flags & TRACE_ITER_BIN) |
1807 | return print_bin_fmt(iter); | |
1808 | ||
5e3ca0ec IM |
1809 | if (trace_flags & TRACE_ITER_HEX) |
1810 | return print_hex_fmt(iter); | |
1811 | ||
f9896bf3 IM |
1812 | if (trace_flags & TRACE_ITER_RAW) |
1813 | return print_raw_fmt(iter); | |
1814 | ||
f9896bf3 IM |
1815 | return print_trace_fmt(iter); |
1816 | } | |
1817 | ||
bc0c38d1 SR |
1818 | static int s_show(struct seq_file *m, void *v) |
1819 | { | |
1820 | struct trace_iterator *iter = v; | |
1821 | ||
1822 | if (iter->ent == NULL) { | |
1823 | if (iter->tr) { | |
1824 | seq_printf(m, "# tracer: %s\n", iter->trace->name); | |
1825 | seq_puts(m, "#\n"); | |
1826 | } | |
8bba1bf5 MM |
1827 | if (iter->trace && iter->trace->print_header) |
1828 | iter->trace->print_header(m); | |
1829 | else if (iter->iter_flags & TRACE_FILE_LAT_FMT) { | |
bc0c38d1 SR |
1830 | /* print nothing if the buffers are empty */ |
1831 | if (trace_empty(iter)) | |
1832 | return 0; | |
1833 | print_trace_header(m, iter); | |
1834 | if (!(trace_flags & TRACE_ITER_VERBOSE)) | |
1835 | print_lat_help_header(m); | |
1836 | } else { | |
1837 | if (!(trace_flags & TRACE_ITER_VERBOSE)) | |
1838 | print_func_help_header(m); | |
1839 | } | |
1840 | } else { | |
f9896bf3 | 1841 | print_trace_line(iter); |
214023c3 | 1842 | trace_print_seq(m, &iter->seq); |
bc0c38d1 SR |
1843 | } |
1844 | ||
1845 | return 0; | |
1846 | } | |
1847 | ||
1848 | static struct seq_operations tracer_seq_ops = { | |
4bf39a94 IM |
1849 | .start = s_start, |
1850 | .next = s_next, | |
1851 | .stop = s_stop, | |
1852 | .show = s_show, | |
bc0c38d1 SR |
1853 | }; |
1854 | ||
e309b41d | 1855 | static struct trace_iterator * |
85a2f9b4 | 1856 | __tracing_open(struct inode *inode, struct file *file) |
bc0c38d1 | 1857 | { |
b04cc6b1 | 1858 | long cpu_file = (long) inode->i_private; |
85a2f9b4 | 1859 | void *fail_ret = ERR_PTR(-ENOMEM); |
bc0c38d1 | 1860 | struct trace_iterator *iter; |
3928a8a2 | 1861 | struct seq_file *m; |
85a2f9b4 | 1862 | int cpu, ret; |
bc0c38d1 | 1863 | |
85a2f9b4 SR |
1864 | if (tracing_disabled) |
1865 | return ERR_PTR(-ENODEV); | |
60a11774 | 1866 | |
bc0c38d1 | 1867 | iter = kzalloc(sizeof(*iter), GFP_KERNEL); |
85a2f9b4 SR |
1868 | if (!iter) |
1869 | return ERR_PTR(-ENOMEM); | |
bc0c38d1 | 1870 | |
d7350c3f FW |
1871 | /* |
1872 | * We make a copy of the current tracer to avoid concurrent | |
1873 | * changes on it while we are reading. | |
1874 | */ | |
bc0c38d1 | 1875 | mutex_lock(&trace_types_lock); |
d7350c3f | 1876 | iter->trace = kzalloc(sizeof(*iter->trace), GFP_KERNEL); |
85a2f9b4 | 1877 | if (!iter->trace) |
d7350c3f | 1878 | goto fail; |
85a2f9b4 | 1879 | |
d7350c3f FW |
1880 | if (current_trace) |
1881 | *iter->trace = *current_trace; | |
1882 | ||
b0dfa978 FW |
1883 | if (!alloc_cpumask_var(&iter->started, GFP_KERNEL)) |
1884 | goto fail; | |
1885 | ||
1886 | cpumask_clear(iter->started); | |
1887 | ||
bc0c38d1 SR |
1888 | if (current_trace && current_trace->print_max) |
1889 | iter->tr = &max_tr; | |
1890 | else | |
b04cc6b1 | 1891 | iter->tr = &global_trace; |
bc0c38d1 | 1892 | iter->pos = -1; |
d7350c3f | 1893 | mutex_init(&iter->mutex); |
b04cc6b1 | 1894 | iter->cpu_file = cpu_file; |
bc0c38d1 | 1895 | |
8bba1bf5 MM |
1896 | /* Notify the tracer early; before we stop tracing. */ |
1897 | if (iter->trace && iter->trace->open) | |
a93751ca | 1898 | iter->trace->open(iter); |
8bba1bf5 | 1899 | |
12ef7d44 SR |
1900 | /* Annotate start of buffers if we had overruns */ |
1901 | if (ring_buffer_overruns(iter->tr->buffer)) | |
1902 | iter->iter_flags |= TRACE_FILE_ANNOTATE; | |
1903 | ||
2f26ebd5 SR |
1904 | /* stop the trace while dumping */ |
1905 | tracing_stop(); | |
1906 | ||
b04cc6b1 FW |
1907 | if (iter->cpu_file == TRACE_PIPE_ALL_CPU) { |
1908 | for_each_tracing_cpu(cpu) { | |
12ef7d44 | 1909 | |
b04cc6b1 FW |
1910 | iter->buffer_iter[cpu] = |
1911 | ring_buffer_read_start(iter->tr->buffer, cpu); | |
2f26ebd5 | 1912 | tracing_iter_reset(iter, cpu); |
b04cc6b1 FW |
1913 | } |
1914 | } else { | |
1915 | cpu = iter->cpu_file; | |
3928a8a2 | 1916 | iter->buffer_iter[cpu] = |
b04cc6b1 | 1917 | ring_buffer_read_start(iter->tr->buffer, cpu); |
2f26ebd5 | 1918 | tracing_iter_reset(iter, cpu); |
3928a8a2 SR |
1919 | } |
1920 | ||
85a2f9b4 SR |
1921 | ret = seq_open(file, &tracer_seq_ops); |
1922 | if (ret < 0) { | |
1923 | fail_ret = ERR_PTR(ret); | |
3928a8a2 | 1924 | goto fail_buffer; |
85a2f9b4 | 1925 | } |
bc0c38d1 | 1926 | |
3928a8a2 SR |
1927 | m = file->private_data; |
1928 | m->private = iter; | |
bc0c38d1 | 1929 | |
bc0c38d1 SR |
1930 | mutex_unlock(&trace_types_lock); |
1931 | ||
bc0c38d1 | 1932 | return iter; |
3928a8a2 SR |
1933 | |
1934 | fail_buffer: | |
1935 | for_each_tracing_cpu(cpu) { | |
1936 | if (iter->buffer_iter[cpu]) | |
1937 | ring_buffer_read_finish(iter->buffer_iter[cpu]); | |
1938 | } | |
b0dfa978 | 1939 | free_cpumask_var(iter->started); |
2f26ebd5 | 1940 | tracing_start(); |
d7350c3f | 1941 | fail: |
3928a8a2 | 1942 | mutex_unlock(&trace_types_lock); |
d7350c3f | 1943 | kfree(iter->trace); |
0bb943c7 | 1944 | kfree(iter); |
3928a8a2 | 1945 | |
85a2f9b4 | 1946 | return fail_ret; |
bc0c38d1 SR |
1947 | } |
1948 | ||
1949 | int tracing_open_generic(struct inode *inode, struct file *filp) | |
1950 | { | |
60a11774 SR |
1951 | if (tracing_disabled) |
1952 | return -ENODEV; | |
1953 | ||
bc0c38d1 SR |
1954 | filp->private_data = inode->i_private; |
1955 | return 0; | |
1956 | } | |
1957 | ||
4fd27358 | 1958 | static int tracing_release(struct inode *inode, struct file *file) |
bc0c38d1 SR |
1959 | { |
1960 | struct seq_file *m = (struct seq_file *)file->private_data; | |
4acd4d00 | 1961 | struct trace_iterator *iter; |
3928a8a2 | 1962 | int cpu; |
bc0c38d1 | 1963 | |
4acd4d00 SR |
1964 | if (!(file->f_mode & FMODE_READ)) |
1965 | return 0; | |
1966 | ||
1967 | iter = m->private; | |
1968 | ||
bc0c38d1 | 1969 | mutex_lock(&trace_types_lock); |
3928a8a2 SR |
1970 | for_each_tracing_cpu(cpu) { |
1971 | if (iter->buffer_iter[cpu]) | |
1972 | ring_buffer_read_finish(iter->buffer_iter[cpu]); | |
1973 | } | |
1974 | ||
bc0c38d1 SR |
1975 | if (iter->trace && iter->trace->close) |
1976 | iter->trace->close(iter); | |
1977 | ||
1978 | /* reenable tracing if it was previously enabled */ | |
9036990d | 1979 | tracing_start(); |
bc0c38d1 SR |
1980 | mutex_unlock(&trace_types_lock); |
1981 | ||
1982 | seq_release(inode, file); | |
d7350c3f | 1983 | mutex_destroy(&iter->mutex); |
b0dfa978 | 1984 | free_cpumask_var(iter->started); |
d7350c3f | 1985 | kfree(iter->trace); |
bc0c38d1 SR |
1986 | kfree(iter); |
1987 | return 0; | |
1988 | } | |
1989 | ||
1990 | static int tracing_open(struct inode *inode, struct file *file) | |
1991 | { | |
85a2f9b4 SR |
1992 | struct trace_iterator *iter; |
1993 | int ret = 0; | |
bc0c38d1 | 1994 | |
4acd4d00 SR |
1995 | /* If this file was open for write, then erase contents */ |
1996 | if ((file->f_mode & FMODE_WRITE) && | |
8650ae32 | 1997 | (file->f_flags & O_TRUNC)) { |
4acd4d00 | 1998 | long cpu = (long) inode->i_private; |
bc0c38d1 | 1999 | |
4acd4d00 SR |
2000 | if (cpu == TRACE_PIPE_ALL_CPU) |
2001 | tracing_reset_online_cpus(&global_trace); | |
2002 | else | |
2003 | tracing_reset(&global_trace, cpu); | |
2004 | } | |
bc0c38d1 | 2005 | |
4acd4d00 SR |
2006 | if (file->f_mode & FMODE_READ) { |
2007 | iter = __tracing_open(inode, file); | |
2008 | if (IS_ERR(iter)) | |
2009 | ret = PTR_ERR(iter); | |
2010 | else if (trace_flags & TRACE_ITER_LATENCY_FMT) | |
2011 | iter->iter_flags |= TRACE_FILE_LAT_FMT; | |
2012 | } | |
bc0c38d1 SR |
2013 | return ret; |
2014 | } | |
2015 | ||
e309b41d | 2016 | static void * |
bc0c38d1 SR |
2017 | t_next(struct seq_file *m, void *v, loff_t *pos) |
2018 | { | |
f129e965 | 2019 | struct tracer *t = v; |
bc0c38d1 SR |
2020 | |
2021 | (*pos)++; | |
2022 | ||
2023 | if (t) | |
2024 | t = t->next; | |
2025 | ||
bc0c38d1 SR |
2026 | return t; |
2027 | } | |
2028 | ||
2029 | static void *t_start(struct seq_file *m, loff_t *pos) | |
2030 | { | |
f129e965 | 2031 | struct tracer *t; |
bc0c38d1 SR |
2032 | loff_t l = 0; |
2033 | ||
2034 | mutex_lock(&trace_types_lock); | |
f129e965 | 2035 | for (t = trace_types; t && l < *pos; t = t_next(m, t, &l)) |
bc0c38d1 SR |
2036 | ; |
2037 | ||
2038 | return t; | |
2039 | } | |
2040 | ||
2041 | static void t_stop(struct seq_file *m, void *p) | |
2042 | { | |
2043 | mutex_unlock(&trace_types_lock); | |
2044 | } | |
2045 | ||
2046 | static int t_show(struct seq_file *m, void *v) | |
2047 | { | |
2048 | struct tracer *t = v; | |
2049 | ||
2050 | if (!t) | |
2051 | return 0; | |
2052 | ||
2053 | seq_printf(m, "%s", t->name); | |
2054 | if (t->next) | |
2055 | seq_putc(m, ' '); | |
2056 | else | |
2057 | seq_putc(m, '\n'); | |
2058 | ||
2059 | return 0; | |
2060 | } | |
2061 | ||
2062 | static struct seq_operations show_traces_seq_ops = { | |
4bf39a94 IM |
2063 | .start = t_start, |
2064 | .next = t_next, | |
2065 | .stop = t_stop, | |
2066 | .show = t_show, | |
bc0c38d1 SR |
2067 | }; |
2068 | ||
2069 | static int show_traces_open(struct inode *inode, struct file *file) | |
2070 | { | |
60a11774 SR |
2071 | if (tracing_disabled) |
2072 | return -ENODEV; | |
2073 | ||
f129e965 | 2074 | return seq_open(file, &show_traces_seq_ops); |
bc0c38d1 SR |
2075 | } |
2076 | ||
4acd4d00 SR |
2077 | static ssize_t |
2078 | tracing_write_stub(struct file *filp, const char __user *ubuf, | |
2079 | size_t count, loff_t *ppos) | |
2080 | { | |
2081 | return count; | |
2082 | } | |
2083 | ||
5e2336a0 | 2084 | static const struct file_operations tracing_fops = { |
4bf39a94 IM |
2085 | .open = tracing_open, |
2086 | .read = seq_read, | |
4acd4d00 | 2087 | .write = tracing_write_stub, |
4bf39a94 IM |
2088 | .llseek = seq_lseek, |
2089 | .release = tracing_release, | |
bc0c38d1 SR |
2090 | }; |
2091 | ||
5e2336a0 | 2092 | static const struct file_operations show_traces_fops = { |
c7078de1 IM |
2093 | .open = show_traces_open, |
2094 | .read = seq_read, | |
2095 | .release = seq_release, | |
2096 | }; | |
2097 | ||
36dfe925 IM |
2098 | /* |
2099 | * Only trace on a CPU if the bitmask is set: | |
2100 | */ | |
9e01c1b7 | 2101 | static cpumask_var_t tracing_cpumask; |
36dfe925 IM |
2102 | |
2103 | /* | |
2104 | * The tracer itself will not take this lock, but still we want | |
2105 | * to provide a consistent cpumask to user-space: | |
2106 | */ | |
2107 | static DEFINE_MUTEX(tracing_cpumask_update_lock); | |
2108 | ||
2109 | /* | |
2110 | * Temporary storage for the character representation of the | |
2111 | * CPU bitmask (and one more byte for the newline): | |
2112 | */ | |
2113 | static char mask_str[NR_CPUS + 1]; | |
2114 | ||
c7078de1 IM |
2115 | static ssize_t |
2116 | tracing_cpumask_read(struct file *filp, char __user *ubuf, | |
2117 | size_t count, loff_t *ppos) | |
2118 | { | |
36dfe925 | 2119 | int len; |
c7078de1 IM |
2120 | |
2121 | mutex_lock(&tracing_cpumask_update_lock); | |
36dfe925 | 2122 | |
9e01c1b7 | 2123 | len = cpumask_scnprintf(mask_str, count, tracing_cpumask); |
36dfe925 IM |
2124 | if (count - len < 2) { |
2125 | count = -EINVAL; | |
2126 | goto out_err; | |
2127 | } | |
2128 | len += sprintf(mask_str + len, "\n"); | |
2129 | count = simple_read_from_buffer(ubuf, count, ppos, mask_str, NR_CPUS+1); | |
2130 | ||
2131 | out_err: | |
c7078de1 IM |
2132 | mutex_unlock(&tracing_cpumask_update_lock); |
2133 | ||
2134 | return count; | |
2135 | } | |
2136 | ||
2137 | static ssize_t | |
2138 | tracing_cpumask_write(struct file *filp, const char __user *ubuf, | |
2139 | size_t count, loff_t *ppos) | |
2140 | { | |
36dfe925 | 2141 | int err, cpu; |
9e01c1b7 RR |
2142 | cpumask_var_t tracing_cpumask_new; |
2143 | ||
2144 | if (!alloc_cpumask_var(&tracing_cpumask_new, GFP_KERNEL)) | |
2145 | return -ENOMEM; | |
c7078de1 | 2146 | |
9e01c1b7 | 2147 | err = cpumask_parse_user(ubuf, count, tracing_cpumask_new); |
c7078de1 | 2148 | if (err) |
36dfe925 IM |
2149 | goto err_unlock; |
2150 | ||
215368e8 LZ |
2151 | mutex_lock(&tracing_cpumask_update_lock); |
2152 | ||
a5e25883 | 2153 | local_irq_disable(); |
92205c23 | 2154 | __raw_spin_lock(&ftrace_max_lock); |
ab46428c | 2155 | for_each_tracing_cpu(cpu) { |
36dfe925 IM |
2156 | /* |
2157 | * Increase/decrease the disabled counter if we are | |
2158 | * about to flip a bit in the cpumask: | |
2159 | */ | |
9e01c1b7 RR |
2160 | if (cpumask_test_cpu(cpu, tracing_cpumask) && |
2161 | !cpumask_test_cpu(cpu, tracing_cpumask_new)) { | |
36dfe925 IM |
2162 | atomic_inc(&global_trace.data[cpu]->disabled); |
2163 | } | |
9e01c1b7 RR |
2164 | if (!cpumask_test_cpu(cpu, tracing_cpumask) && |
2165 | cpumask_test_cpu(cpu, tracing_cpumask_new)) { | |
36dfe925 IM |
2166 | atomic_dec(&global_trace.data[cpu]->disabled); |
2167 | } | |
2168 | } | |
92205c23 | 2169 | __raw_spin_unlock(&ftrace_max_lock); |
a5e25883 | 2170 | local_irq_enable(); |
36dfe925 | 2171 | |
9e01c1b7 | 2172 | cpumask_copy(tracing_cpumask, tracing_cpumask_new); |
36dfe925 IM |
2173 | |
2174 | mutex_unlock(&tracing_cpumask_update_lock); | |
9e01c1b7 | 2175 | free_cpumask_var(tracing_cpumask_new); |
c7078de1 IM |
2176 | |
2177 | return count; | |
36dfe925 IM |
2178 | |
2179 | err_unlock: | |
215368e8 | 2180 | free_cpumask_var(tracing_cpumask_new); |
36dfe925 IM |
2181 | |
2182 | return err; | |
c7078de1 IM |
2183 | } |
2184 | ||
5e2336a0 | 2185 | static const struct file_operations tracing_cpumask_fops = { |
c7078de1 IM |
2186 | .open = tracing_open_generic, |
2187 | .read = tracing_cpumask_read, | |
2188 | .write = tracing_cpumask_write, | |
bc0c38d1 SR |
2189 | }; |
2190 | ||
2191 | static ssize_t | |
ee6bce52 | 2192 | tracing_trace_options_read(struct file *filp, char __user *ubuf, |
bc0c38d1 SR |
2193 | size_t cnt, loff_t *ppos) |
2194 | { | |
d8e83d26 SR |
2195 | struct tracer_opt *trace_opts; |
2196 | u32 tracer_flags; | |
2197 | int len = 0; | |
bc0c38d1 SR |
2198 | char *buf; |
2199 | int r = 0; | |
d8e83d26 | 2200 | int i; |
adf9f195 | 2201 | |
bc0c38d1 | 2202 | |
c3706f00 | 2203 | /* calculate max size */ |
bc0c38d1 SR |
2204 | for (i = 0; trace_options[i]; i++) { |
2205 | len += strlen(trace_options[i]); | |
5c6a3ae1 | 2206 | len += 3; /* "no" and newline */ |
bc0c38d1 SR |
2207 | } |
2208 | ||
d8e83d26 SR |
2209 | mutex_lock(&trace_types_lock); |
2210 | tracer_flags = current_trace->flags->val; | |
2211 | trace_opts = current_trace->flags->opts; | |
2212 | ||
adf9f195 FW |
2213 | /* |
2214 | * Increase the size with names of options specific | |
2215 | * of the current tracer. | |
2216 | */ | |
2217 | for (i = 0; trace_opts[i].name; i++) { | |
2218 | len += strlen(trace_opts[i].name); | |
5c6a3ae1 | 2219 | len += 3; /* "no" and newline */ |
adf9f195 FW |
2220 | } |
2221 | ||
ff4e9da2 XG |
2222 | /* +1 for \0 */ |
2223 | buf = kmalloc(len + 1, GFP_KERNEL); | |
d8e83d26 SR |
2224 | if (!buf) { |
2225 | mutex_unlock(&trace_types_lock); | |
bc0c38d1 | 2226 | return -ENOMEM; |
d8e83d26 | 2227 | } |
bc0c38d1 SR |
2228 | |
2229 | for (i = 0; trace_options[i]; i++) { | |
2230 | if (trace_flags & (1 << i)) | |
5c6a3ae1 | 2231 | r += sprintf(buf + r, "%s\n", trace_options[i]); |
bc0c38d1 | 2232 | else |
5c6a3ae1 | 2233 | r += sprintf(buf + r, "no%s\n", trace_options[i]); |
bc0c38d1 SR |
2234 | } |
2235 | ||
adf9f195 FW |
2236 | for (i = 0; trace_opts[i].name; i++) { |
2237 | if (tracer_flags & trace_opts[i].bit) | |
5c6a3ae1 | 2238 | r += sprintf(buf + r, "%s\n", |
adf9f195 FW |
2239 | trace_opts[i].name); |
2240 | else | |
5c6a3ae1 | 2241 | r += sprintf(buf + r, "no%s\n", |
adf9f195 FW |
2242 | trace_opts[i].name); |
2243 | } | |
d8e83d26 | 2244 | mutex_unlock(&trace_types_lock); |
adf9f195 | 2245 | |
ff4e9da2 | 2246 | WARN_ON(r >= len + 1); |
bc0c38d1 | 2247 | |
36dfe925 | 2248 | r = simple_read_from_buffer(ubuf, cnt, ppos, buf, r); |
bc0c38d1 SR |
2249 | |
2250 | kfree(buf); | |
bc0c38d1 SR |
2251 | return r; |
2252 | } | |
2253 | ||
adf9f195 FW |
2254 | /* Try to assign a tracer specific option */ |
2255 | static int set_tracer_option(struct tracer *trace, char *cmp, int neg) | |
2256 | { | |
7770841e | 2257 | struct tracer_flags *tracer_flags = trace->flags; |
adf9f195 FW |
2258 | struct tracer_opt *opts = NULL; |
2259 | int ret = 0, i = 0; | |
2260 | int len; | |
2261 | ||
7770841e Z |
2262 | for (i = 0; tracer_flags->opts[i].name; i++) { |
2263 | opts = &tracer_flags->opts[i]; | |
adf9f195 FW |
2264 | len = strlen(opts->name); |
2265 | ||
2266 | if (strncmp(cmp, opts->name, len) == 0) { | |
7770841e | 2267 | ret = trace->set_flag(tracer_flags->val, |
adf9f195 FW |
2268 | opts->bit, !neg); |
2269 | break; | |
2270 | } | |
2271 | } | |
2272 | /* Not found */ | |
7770841e | 2273 | if (!tracer_flags->opts[i].name) |
adf9f195 FW |
2274 | return -EINVAL; |
2275 | ||
2276 | /* Refused to handle */ | |
2277 | if (ret) | |
2278 | return ret; | |
2279 | ||
2280 | if (neg) | |
7770841e | 2281 | tracer_flags->val &= ~opts->bit; |
adf9f195 | 2282 | else |
7770841e | 2283 | tracer_flags->val |= opts->bit; |
adf9f195 FW |
2284 | |
2285 | return 0; | |
2286 | } | |
2287 | ||
af4617bd SR |
2288 | static void set_tracer_flags(unsigned int mask, int enabled) |
2289 | { | |
2290 | /* do nothing if flag is already set */ | |
2291 | if (!!(trace_flags & mask) == !!enabled) | |
2292 | return; | |
2293 | ||
2294 | if (enabled) | |
2295 | trace_flags |= mask; | |
2296 | else | |
2297 | trace_flags &= ~mask; | |
af4617bd SR |
2298 | } |
2299 | ||
bc0c38d1 | 2300 | static ssize_t |
ee6bce52 | 2301 | tracing_trace_options_write(struct file *filp, const char __user *ubuf, |
bc0c38d1 SR |
2302 | size_t cnt, loff_t *ppos) |
2303 | { | |
2304 | char buf[64]; | |
2305 | char *cmp = buf; | |
2306 | int neg = 0; | |
adf9f195 | 2307 | int ret; |
bc0c38d1 SR |
2308 | int i; |
2309 | ||
cffae437 SR |
2310 | if (cnt >= sizeof(buf)) |
2311 | return -EINVAL; | |
bc0c38d1 SR |
2312 | |
2313 | if (copy_from_user(&buf, ubuf, cnt)) | |
2314 | return -EFAULT; | |
2315 | ||
2316 | buf[cnt] = 0; | |
2317 | ||
2318 | if (strncmp(buf, "no", 2) == 0) { | |
2319 | neg = 1; | |
2320 | cmp += 2; | |
2321 | } | |
2322 | ||
2323 | for (i = 0; trace_options[i]; i++) { | |
2324 | int len = strlen(trace_options[i]); | |
2325 | ||
2326 | if (strncmp(cmp, trace_options[i], len) == 0) { | |
af4617bd | 2327 | set_tracer_flags(1 << i, !neg); |
bc0c38d1 SR |
2328 | break; |
2329 | } | |
2330 | } | |
adf9f195 FW |
2331 | |
2332 | /* If no option could be set, test the specific tracer options */ | |
2333 | if (!trace_options[i]) { | |
d8e83d26 | 2334 | mutex_lock(&trace_types_lock); |
adf9f195 | 2335 | ret = set_tracer_option(current_trace, cmp, neg); |
d8e83d26 | 2336 | mutex_unlock(&trace_types_lock); |
adf9f195 FW |
2337 | if (ret) |
2338 | return ret; | |
2339 | } | |
bc0c38d1 SR |
2340 | |
2341 | filp->f_pos += cnt; | |
2342 | ||
2343 | return cnt; | |
2344 | } | |
2345 | ||
5e2336a0 | 2346 | static const struct file_operations tracing_iter_fops = { |
c7078de1 | 2347 | .open = tracing_open_generic, |
ee6bce52 SR |
2348 | .read = tracing_trace_options_read, |
2349 | .write = tracing_trace_options_write, | |
bc0c38d1 SR |
2350 | }; |
2351 | ||
7bd2f24c IM |
2352 | static const char readme_msg[] = |
2353 | "tracing mini-HOWTO:\n\n" | |
156f5a78 GL |
2354 | "# mount -t debugfs nodev /sys/kernel/debug\n\n" |
2355 | "# cat /sys/kernel/debug/tracing/available_tracers\n" | |
bc2b6871 | 2356 | "wakeup preemptirqsoff preemptoff irqsoff function sched_switch nop\n\n" |
156f5a78 | 2357 | "# cat /sys/kernel/debug/tracing/current_tracer\n" |
bc2b6871 | 2358 | "nop\n" |
156f5a78 GL |
2359 | "# echo sched_switch > /sys/kernel/debug/tracing/current_tracer\n" |
2360 | "# cat /sys/kernel/debug/tracing/current_tracer\n" | |
7bd2f24c | 2361 | "sched_switch\n" |
156f5a78 | 2362 | "# cat /sys/kernel/debug/tracing/trace_options\n" |
7bd2f24c | 2363 | "noprint-parent nosym-offset nosym-addr noverbose\n" |
156f5a78 GL |
2364 | "# echo print-parent > /sys/kernel/debug/tracing/trace_options\n" |
2365 | "# echo 1 > /sys/kernel/debug/tracing/tracing_enabled\n" | |
2366 | "# cat /sys/kernel/debug/tracing/trace > /tmp/trace.txt\n" | |
2367 | "# echo 0 > /sys/kernel/debug/tracing/tracing_enabled\n" | |
7bd2f24c IM |
2368 | ; |
2369 | ||
2370 | static ssize_t | |
2371 | tracing_readme_read(struct file *filp, char __user *ubuf, | |
2372 | size_t cnt, loff_t *ppos) | |
2373 | { | |
2374 | return simple_read_from_buffer(ubuf, cnt, ppos, | |
2375 | readme_msg, strlen(readme_msg)); | |
2376 | } | |
2377 | ||
5e2336a0 | 2378 | static const struct file_operations tracing_readme_fops = { |
c7078de1 IM |
2379 | .open = tracing_open_generic, |
2380 | .read = tracing_readme_read, | |
7bd2f24c IM |
2381 | }; |
2382 | ||
69abe6a5 AP |
2383 | static ssize_t |
2384 | tracing_saved_cmdlines_read(struct file *file, char __user *ubuf, | |
2385 | size_t cnt, loff_t *ppos) | |
2386 | { | |
2387 | char *buf_comm; | |
2388 | char *file_buf; | |
2389 | char *buf; | |
2390 | int len = 0; | |
2391 | int pid; | |
2392 | int i; | |
2393 | ||
2394 | file_buf = kmalloc(SAVED_CMDLINES*(16+TASK_COMM_LEN), GFP_KERNEL); | |
2395 | if (!file_buf) | |
2396 | return -ENOMEM; | |
2397 | ||
2398 | buf_comm = kmalloc(TASK_COMM_LEN, GFP_KERNEL); | |
2399 | if (!buf_comm) { | |
2400 | kfree(file_buf); | |
2401 | return -ENOMEM; | |
2402 | } | |
2403 | ||
2404 | buf = file_buf; | |
2405 | ||
2406 | for (i = 0; i < SAVED_CMDLINES; i++) { | |
2407 | int r; | |
2408 | ||
2409 | pid = map_cmdline_to_pid[i]; | |
2410 | if (pid == -1 || pid == NO_CMDLINE_MAP) | |
2411 | continue; | |
2412 | ||
2413 | trace_find_cmdline(pid, buf_comm); | |
2414 | r = sprintf(buf, "%d %s\n", pid, buf_comm); | |
2415 | buf += r; | |
2416 | len += r; | |
2417 | } | |
2418 | ||
2419 | len = simple_read_from_buffer(ubuf, cnt, ppos, | |
2420 | file_buf, len); | |
2421 | ||
2422 | kfree(file_buf); | |
2423 | kfree(buf_comm); | |
2424 | ||
2425 | return len; | |
2426 | } | |
2427 | ||
2428 | static const struct file_operations tracing_saved_cmdlines_fops = { | |
2429 | .open = tracing_open_generic, | |
2430 | .read = tracing_saved_cmdlines_read, | |
2431 | }; | |
2432 | ||
bc0c38d1 SR |
2433 | static ssize_t |
2434 | tracing_ctrl_read(struct file *filp, char __user *ubuf, | |
2435 | size_t cnt, loff_t *ppos) | |
2436 | { | |
bc0c38d1 SR |
2437 | char buf[64]; |
2438 | int r; | |
2439 | ||
9036990d | 2440 | r = sprintf(buf, "%u\n", tracer_enabled); |
4e3c3333 | 2441 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, r); |
bc0c38d1 SR |
2442 | } |
2443 | ||
2444 | static ssize_t | |
2445 | tracing_ctrl_write(struct file *filp, const char __user *ubuf, | |
2446 | size_t cnt, loff_t *ppos) | |
2447 | { | |
2448 | struct trace_array *tr = filp->private_data; | |
bc0c38d1 | 2449 | char buf[64]; |
5e39841c | 2450 | unsigned long val; |
c6caeeb1 | 2451 | int ret; |
bc0c38d1 | 2452 | |
cffae437 SR |
2453 | if (cnt >= sizeof(buf)) |
2454 | return -EINVAL; | |
bc0c38d1 SR |
2455 | |
2456 | if (copy_from_user(&buf, ubuf, cnt)) | |
2457 | return -EFAULT; | |
2458 | ||
2459 | buf[cnt] = 0; | |
2460 | ||
c6caeeb1 SR |
2461 | ret = strict_strtoul(buf, 10, &val); |
2462 | if (ret < 0) | |
2463 | return ret; | |
bc0c38d1 SR |
2464 | |
2465 | val = !!val; | |
2466 | ||
2467 | mutex_lock(&trace_types_lock); | |
9036990d SR |
2468 | if (tracer_enabled ^ val) { |
2469 | if (val) { | |
bc0c38d1 | 2470 | tracer_enabled = 1; |
9036990d SR |
2471 | if (current_trace->start) |
2472 | current_trace->start(tr); | |
2473 | tracing_start(); | |
2474 | } else { | |
bc0c38d1 | 2475 | tracer_enabled = 0; |
9036990d SR |
2476 | tracing_stop(); |
2477 | if (current_trace->stop) | |
2478 | current_trace->stop(tr); | |
2479 | } | |
bc0c38d1 SR |
2480 | } |
2481 | mutex_unlock(&trace_types_lock); | |
2482 | ||
2483 | filp->f_pos += cnt; | |
2484 | ||
2485 | return cnt; | |
2486 | } | |
2487 | ||
2488 | static ssize_t | |
2489 | tracing_set_trace_read(struct file *filp, char __user *ubuf, | |
2490 | size_t cnt, loff_t *ppos) | |
2491 | { | |
2492 | char buf[max_tracer_type_len+2]; | |
2493 | int r; | |
2494 | ||
2495 | mutex_lock(&trace_types_lock); | |
2496 | if (current_trace) | |
2497 | r = sprintf(buf, "%s\n", current_trace->name); | |
2498 | else | |
2499 | r = sprintf(buf, "\n"); | |
2500 | mutex_unlock(&trace_types_lock); | |
2501 | ||
4bf39a94 | 2502 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, r); |
bc0c38d1 SR |
2503 | } |
2504 | ||
b6f11df2 ACM |
2505 | int tracer_init(struct tracer *t, struct trace_array *tr) |
2506 | { | |
2507 | tracing_reset_online_cpus(tr); | |
2508 | return t->init(tr); | |
2509 | } | |
2510 | ||
73c5162a SR |
2511 | static int tracing_resize_ring_buffer(unsigned long size) |
2512 | { | |
2513 | int ret; | |
2514 | ||
2515 | /* | |
2516 | * If kernel or user changes the size of the ring buffer | |
a123c52b SR |
2517 | * we use the size that was given, and we can forget about |
2518 | * expanding it later. | |
73c5162a SR |
2519 | */ |
2520 | ring_buffer_expanded = 1; | |
2521 | ||
2522 | ret = ring_buffer_resize(global_trace.buffer, size); | |
2523 | if (ret < 0) | |
2524 | return ret; | |
2525 | ||
2526 | ret = ring_buffer_resize(max_tr.buffer, size); | |
2527 | if (ret < 0) { | |
2528 | int r; | |
2529 | ||
2530 | r = ring_buffer_resize(global_trace.buffer, | |
2531 | global_trace.entries); | |
2532 | if (r < 0) { | |
a123c52b SR |
2533 | /* |
2534 | * AARGH! We are left with different | |
2535 | * size max buffer!!!! | |
2536 | * The max buffer is our "snapshot" buffer. | |
2537 | * When a tracer needs a snapshot (one of the | |
2538 | * latency tracers), it swaps the max buffer | |
2539 | * with the saved snap shot. We succeeded to | |
2540 | * update the size of the main buffer, but failed to | |
2541 | * update the size of the max buffer. But when we tried | |
2542 | * to reset the main buffer to the original size, we | |
2543 | * failed there too. This is very unlikely to | |
2544 | * happen, but if it does, warn and kill all | |
2545 | * tracing. | |
2546 | */ | |
73c5162a SR |
2547 | WARN_ON(1); |
2548 | tracing_disabled = 1; | |
2549 | } | |
2550 | return ret; | |
2551 | } | |
2552 | ||
2553 | global_trace.entries = size; | |
2554 | ||
2555 | return ret; | |
2556 | } | |
2557 | ||
1852fcce SR |
2558 | /** |
2559 | * tracing_update_buffers - used by tracing facility to expand ring buffers | |
2560 | * | |
2561 | * To save on memory when the tracing is never used on a system with it | |
2562 | * configured in. The ring buffers are set to a minimum size. But once | |
2563 | * a user starts to use the tracing facility, then they need to grow | |
2564 | * to their default size. | |
2565 | * | |
2566 | * This function is to be called when a tracer is about to be used. | |
2567 | */ | |
2568 | int tracing_update_buffers(void) | |
2569 | { | |
2570 | int ret = 0; | |
2571 | ||
1027fcb2 | 2572 | mutex_lock(&trace_types_lock); |
1852fcce SR |
2573 | if (!ring_buffer_expanded) |
2574 | ret = tracing_resize_ring_buffer(trace_buf_size); | |
1027fcb2 | 2575 | mutex_unlock(&trace_types_lock); |
1852fcce SR |
2576 | |
2577 | return ret; | |
2578 | } | |
2579 | ||
577b785f SR |
2580 | struct trace_option_dentry; |
2581 | ||
2582 | static struct trace_option_dentry * | |
2583 | create_trace_option_files(struct tracer *tracer); | |
2584 | ||
2585 | static void | |
2586 | destroy_trace_option_files(struct trace_option_dentry *topts); | |
2587 | ||
b2821ae6 | 2588 | static int tracing_set_tracer(const char *buf) |
bc0c38d1 | 2589 | { |
577b785f | 2590 | static struct trace_option_dentry *topts; |
bc0c38d1 SR |
2591 | struct trace_array *tr = &global_trace; |
2592 | struct tracer *t; | |
d9e54076 | 2593 | int ret = 0; |
bc0c38d1 | 2594 | |
1027fcb2 SR |
2595 | mutex_lock(&trace_types_lock); |
2596 | ||
73c5162a SR |
2597 | if (!ring_buffer_expanded) { |
2598 | ret = tracing_resize_ring_buffer(trace_buf_size); | |
2599 | if (ret < 0) | |
59f586db | 2600 | goto out; |
73c5162a SR |
2601 | ret = 0; |
2602 | } | |
2603 | ||
bc0c38d1 SR |
2604 | for (t = trace_types; t; t = t->next) { |
2605 | if (strcmp(t->name, buf) == 0) | |
2606 | break; | |
2607 | } | |
c2931e05 FW |
2608 | if (!t) { |
2609 | ret = -EINVAL; | |
2610 | goto out; | |
2611 | } | |
2612 | if (t == current_trace) | |
bc0c38d1 SR |
2613 | goto out; |
2614 | ||
9f029e83 | 2615 | trace_branch_disable(); |
bc0c38d1 SR |
2616 | if (current_trace && current_trace->reset) |
2617 | current_trace->reset(tr); | |
2618 | ||
577b785f SR |
2619 | destroy_trace_option_files(topts); |
2620 | ||
bc0c38d1 | 2621 | current_trace = t; |
577b785f SR |
2622 | |
2623 | topts = create_trace_option_files(current_trace); | |
2624 | ||
1c80025a | 2625 | if (t->init) { |
b6f11df2 | 2626 | ret = tracer_init(t, tr); |
1c80025a FW |
2627 | if (ret) |
2628 | goto out; | |
2629 | } | |
bc0c38d1 | 2630 | |
9f029e83 | 2631 | trace_branch_enable(tr); |
bc0c38d1 SR |
2632 | out: |
2633 | mutex_unlock(&trace_types_lock); | |
2634 | ||
d9e54076 PZ |
2635 | return ret; |
2636 | } | |
2637 | ||
2638 | static ssize_t | |
2639 | tracing_set_trace_write(struct file *filp, const char __user *ubuf, | |
2640 | size_t cnt, loff_t *ppos) | |
2641 | { | |
2642 | char buf[max_tracer_type_len+1]; | |
2643 | int i; | |
2644 | size_t ret; | |
e6e7a65a FW |
2645 | int err; |
2646 | ||
2647 | ret = cnt; | |
d9e54076 PZ |
2648 | |
2649 | if (cnt > max_tracer_type_len) | |
2650 | cnt = max_tracer_type_len; | |
2651 | ||
2652 | if (copy_from_user(&buf, ubuf, cnt)) | |
2653 | return -EFAULT; | |
2654 | ||
2655 | buf[cnt] = 0; | |
2656 | ||
2657 | /* strip ending whitespace. */ | |
2658 | for (i = cnt - 1; i > 0 && isspace(buf[i]); i--) | |
2659 | buf[i] = 0; | |
2660 | ||
e6e7a65a FW |
2661 | err = tracing_set_tracer(buf); |
2662 | if (err) | |
2663 | return err; | |
d9e54076 | 2664 | |
e6e7a65a | 2665 | filp->f_pos += ret; |
bc0c38d1 | 2666 | |
c2931e05 | 2667 | return ret; |
bc0c38d1 SR |
2668 | } |
2669 | ||
2670 | static ssize_t | |
2671 | tracing_max_lat_read(struct file *filp, char __user *ubuf, | |
2672 | size_t cnt, loff_t *ppos) | |
2673 | { | |
2674 | unsigned long *ptr = filp->private_data; | |
2675 | char buf[64]; | |
2676 | int r; | |
2677 | ||
cffae437 | 2678 | r = snprintf(buf, sizeof(buf), "%ld\n", |
bc0c38d1 | 2679 | *ptr == (unsigned long)-1 ? -1 : nsecs_to_usecs(*ptr)); |
cffae437 SR |
2680 | if (r > sizeof(buf)) |
2681 | r = sizeof(buf); | |
4bf39a94 | 2682 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, r); |
bc0c38d1 SR |
2683 | } |
2684 | ||
2685 | static ssize_t | |
2686 | tracing_max_lat_write(struct file *filp, const char __user *ubuf, | |
2687 | size_t cnt, loff_t *ppos) | |
2688 | { | |
5e39841c | 2689 | unsigned long *ptr = filp->private_data; |
bc0c38d1 | 2690 | char buf[64]; |
5e39841c | 2691 | unsigned long val; |
c6caeeb1 | 2692 | int ret; |
bc0c38d1 | 2693 | |
cffae437 SR |
2694 | if (cnt >= sizeof(buf)) |
2695 | return -EINVAL; | |
bc0c38d1 SR |
2696 | |
2697 | if (copy_from_user(&buf, ubuf, cnt)) | |
2698 | return -EFAULT; | |
2699 | ||
2700 | buf[cnt] = 0; | |
2701 | ||
c6caeeb1 SR |
2702 | ret = strict_strtoul(buf, 10, &val); |
2703 | if (ret < 0) | |
2704 | return ret; | |
bc0c38d1 SR |
2705 | |
2706 | *ptr = val * 1000; | |
2707 | ||
2708 | return cnt; | |
2709 | } | |
2710 | ||
b3806b43 SR |
2711 | static int tracing_open_pipe(struct inode *inode, struct file *filp) |
2712 | { | |
b04cc6b1 | 2713 | long cpu_file = (long) inode->i_private; |
b3806b43 | 2714 | struct trace_iterator *iter; |
b04cc6b1 | 2715 | int ret = 0; |
b3806b43 SR |
2716 | |
2717 | if (tracing_disabled) | |
2718 | return -ENODEV; | |
2719 | ||
b04cc6b1 FW |
2720 | mutex_lock(&trace_types_lock); |
2721 | ||
2722 | /* We only allow one reader per cpu */ | |
2723 | if (cpu_file == TRACE_PIPE_ALL_CPU) { | |
2724 | if (!cpumask_empty(tracing_reader_cpumask)) { | |
2725 | ret = -EBUSY; | |
2726 | goto out; | |
2727 | } | |
2728 | cpumask_setall(tracing_reader_cpumask); | |
2729 | } else { | |
2730 | if (!cpumask_test_cpu(cpu_file, tracing_reader_cpumask)) | |
2731 | cpumask_set_cpu(cpu_file, tracing_reader_cpumask); | |
2732 | else { | |
2733 | ret = -EBUSY; | |
2734 | goto out; | |
2735 | } | |
b3806b43 SR |
2736 | } |
2737 | ||
2738 | /* create a buffer to store the information to pass to userspace */ | |
2739 | iter = kzalloc(sizeof(*iter), GFP_KERNEL); | |
b04cc6b1 FW |
2740 | if (!iter) { |
2741 | ret = -ENOMEM; | |
2742 | goto out; | |
2743 | } | |
b3806b43 | 2744 | |
d7350c3f FW |
2745 | /* |
2746 | * We make a copy of the current tracer to avoid concurrent | |
2747 | * changes on it while we are reading. | |
2748 | */ | |
2749 | iter->trace = kmalloc(sizeof(*iter->trace), GFP_KERNEL); | |
2750 | if (!iter->trace) { | |
2751 | ret = -ENOMEM; | |
2752 | goto fail; | |
2753 | } | |
2754 | if (current_trace) | |
2755 | *iter->trace = *current_trace; | |
2756 | ||
4462344e | 2757 | if (!alloc_cpumask_var(&iter->started, GFP_KERNEL)) { |
b04cc6b1 | 2758 | ret = -ENOMEM; |
d7350c3f | 2759 | goto fail; |
4462344e RR |
2760 | } |
2761 | ||
a309720c | 2762 | /* trace pipe does not show start of buffer */ |
4462344e | 2763 | cpumask_setall(iter->started); |
a309720c | 2764 | |
112f38a7 SR |
2765 | if (trace_flags & TRACE_ITER_LATENCY_FMT) |
2766 | iter->iter_flags |= TRACE_FILE_LAT_FMT; | |
2767 | ||
b04cc6b1 | 2768 | iter->cpu_file = cpu_file; |
b3806b43 | 2769 | iter->tr = &global_trace; |
d7350c3f | 2770 | mutex_init(&iter->mutex); |
b3806b43 SR |
2771 | filp->private_data = iter; |
2772 | ||
107bad8b SR |
2773 | if (iter->trace->pipe_open) |
2774 | iter->trace->pipe_open(iter); | |
107bad8b | 2775 | |
b04cc6b1 FW |
2776 | out: |
2777 | mutex_unlock(&trace_types_lock); | |
2778 | return ret; | |
d7350c3f FW |
2779 | |
2780 | fail: | |
2781 | kfree(iter->trace); | |
2782 | kfree(iter); | |
2783 | mutex_unlock(&trace_types_lock); | |
2784 | return ret; | |
b3806b43 SR |
2785 | } |
2786 | ||
2787 | static int tracing_release_pipe(struct inode *inode, struct file *file) | |
2788 | { | |
2789 | struct trace_iterator *iter = file->private_data; | |
2790 | ||
b04cc6b1 FW |
2791 | mutex_lock(&trace_types_lock); |
2792 | ||
2793 | if (iter->cpu_file == TRACE_PIPE_ALL_CPU) | |
2794 | cpumask_clear(tracing_reader_cpumask); | |
2795 | else | |
2796 | cpumask_clear_cpu(iter->cpu_file, tracing_reader_cpumask); | |
2797 | ||
2798 | mutex_unlock(&trace_types_lock); | |
2799 | ||
4462344e | 2800 | free_cpumask_var(iter->started); |
d7350c3f FW |
2801 | mutex_destroy(&iter->mutex); |
2802 | kfree(iter->trace); | |
b3806b43 | 2803 | kfree(iter); |
b3806b43 SR |
2804 | |
2805 | return 0; | |
2806 | } | |
2807 | ||
2a2cc8f7 SSP |
2808 | static unsigned int |
2809 | tracing_poll_pipe(struct file *filp, poll_table *poll_table) | |
2810 | { | |
2811 | struct trace_iterator *iter = filp->private_data; | |
2812 | ||
2813 | if (trace_flags & TRACE_ITER_BLOCK) { | |
2814 | /* | |
2815 | * Always select as readable when in blocking mode | |
2816 | */ | |
2817 | return POLLIN | POLLRDNORM; | |
afc2abc0 | 2818 | } else { |
2a2cc8f7 SSP |
2819 | if (!trace_empty(iter)) |
2820 | return POLLIN | POLLRDNORM; | |
2821 | poll_wait(filp, &trace_wait, poll_table); | |
2822 | if (!trace_empty(iter)) | |
2823 | return POLLIN | POLLRDNORM; | |
2824 | ||
2825 | return 0; | |
2826 | } | |
2827 | } | |
2828 | ||
6eaaa5d5 FW |
2829 | |
2830 | void default_wait_pipe(struct trace_iterator *iter) | |
2831 | { | |
2832 | DEFINE_WAIT(wait); | |
2833 | ||
2834 | prepare_to_wait(&trace_wait, &wait, TASK_INTERRUPTIBLE); | |
2835 | ||
2836 | if (trace_empty(iter)) | |
2837 | schedule(); | |
2838 | ||
2839 | finish_wait(&trace_wait, &wait); | |
2840 | } | |
2841 | ||
2842 | /* | |
2843 | * This is a make-shift waitqueue. | |
2844 | * A tracer might use this callback on some rare cases: | |
2845 | * | |
2846 | * 1) the current tracer might hold the runqueue lock when it wakes up | |
2847 | * a reader, hence a deadlock (sched, function, and function graph tracers) | |
2848 | * 2) the function tracers, trace all functions, we don't want | |
2849 | * the overhead of calling wake_up and friends | |
2850 | * (and tracing them too) | |
2851 | * | |
2852 | * Anyway, this is really very primitive wakeup. | |
2853 | */ | |
2854 | void poll_wait_pipe(struct trace_iterator *iter) | |
2855 | { | |
2856 | set_current_state(TASK_INTERRUPTIBLE); | |
2857 | /* sleep for 100 msecs, and try again. */ | |
2858 | schedule_timeout(HZ / 10); | |
2859 | } | |
2860 | ||
ff98781b EGM |
2861 | /* Must be called with trace_types_lock mutex held. */ |
2862 | static int tracing_wait_pipe(struct file *filp) | |
b3806b43 SR |
2863 | { |
2864 | struct trace_iterator *iter = filp->private_data; | |
b3806b43 | 2865 | |
b3806b43 | 2866 | while (trace_empty(iter)) { |
2dc8f095 | 2867 | |
107bad8b | 2868 | if ((filp->f_flags & O_NONBLOCK)) { |
ff98781b | 2869 | return -EAGAIN; |
107bad8b | 2870 | } |
2dc8f095 | 2871 | |
d7350c3f | 2872 | mutex_unlock(&iter->mutex); |
107bad8b | 2873 | |
6eaaa5d5 | 2874 | iter->trace->wait_pipe(iter); |
b3806b43 | 2875 | |
d7350c3f | 2876 | mutex_lock(&iter->mutex); |
107bad8b | 2877 | |
6eaaa5d5 | 2878 | if (signal_pending(current)) |
ff98781b | 2879 | return -EINTR; |
b3806b43 SR |
2880 | |
2881 | /* | |
2882 | * We block until we read something and tracing is disabled. | |
2883 | * We still block if tracing is disabled, but we have never | |
2884 | * read anything. This allows a user to cat this file, and | |
2885 | * then enable tracing. But after we have read something, | |
2886 | * we give an EOF when tracing is again disabled. | |
2887 | * | |
2888 | * iter->pos will be 0 if we haven't read anything. | |
2889 | */ | |
2890 | if (!tracer_enabled && iter->pos) | |
2891 | break; | |
b3806b43 SR |
2892 | } |
2893 | ||
ff98781b EGM |
2894 | return 1; |
2895 | } | |
2896 | ||
2897 | /* | |
2898 | * Consumer reader. | |
2899 | */ | |
2900 | static ssize_t | |
2901 | tracing_read_pipe(struct file *filp, char __user *ubuf, | |
2902 | size_t cnt, loff_t *ppos) | |
2903 | { | |
2904 | struct trace_iterator *iter = filp->private_data; | |
d7350c3f | 2905 | static struct tracer *old_tracer; |
ff98781b EGM |
2906 | ssize_t sret; |
2907 | ||
2908 | /* return any leftover data */ | |
2909 | sret = trace_seq_to_user(&iter->seq, ubuf, cnt); | |
2910 | if (sret != -EBUSY) | |
2911 | return sret; | |
2912 | ||
f9520750 | 2913 | trace_seq_init(&iter->seq); |
ff98781b | 2914 | |
d7350c3f | 2915 | /* copy the tracer to avoid using a global lock all around */ |
ff98781b | 2916 | mutex_lock(&trace_types_lock); |
d7350c3f FW |
2917 | if (unlikely(old_tracer != current_trace && current_trace)) { |
2918 | old_tracer = current_trace; | |
2919 | *iter->trace = *current_trace; | |
2920 | } | |
2921 | mutex_unlock(&trace_types_lock); | |
2922 | ||
2923 | /* | |
2924 | * Avoid more than one consumer on a single file descriptor | |
2925 | * This is just a matter of traces coherency, the ring buffer itself | |
2926 | * is protected. | |
2927 | */ | |
2928 | mutex_lock(&iter->mutex); | |
ff98781b EGM |
2929 | if (iter->trace->read) { |
2930 | sret = iter->trace->read(iter, filp, ubuf, cnt, ppos); | |
2931 | if (sret) | |
2932 | goto out; | |
2933 | } | |
2934 | ||
2935 | waitagain: | |
2936 | sret = tracing_wait_pipe(filp); | |
2937 | if (sret <= 0) | |
2938 | goto out; | |
2939 | ||
b3806b43 | 2940 | /* stop when tracing is finished */ |
ff98781b EGM |
2941 | if (trace_empty(iter)) { |
2942 | sret = 0; | |
107bad8b | 2943 | goto out; |
ff98781b | 2944 | } |
b3806b43 SR |
2945 | |
2946 | if (cnt >= PAGE_SIZE) | |
2947 | cnt = PAGE_SIZE - 1; | |
2948 | ||
53d0aa77 | 2949 | /* reset all but tr, trace, and overruns */ |
53d0aa77 SR |
2950 | memset(&iter->seq, 0, |
2951 | sizeof(struct trace_iterator) - | |
2952 | offsetof(struct trace_iterator, seq)); | |
4823ed7e | 2953 | iter->pos = -1; |
b3806b43 | 2954 | |
4f535968 | 2955 | trace_event_read_lock(); |
088b1e42 | 2956 | while (find_next_entry_inc(iter) != NULL) { |
2c4f035f | 2957 | enum print_line_t ret; |
088b1e42 SR |
2958 | int len = iter->seq.len; |
2959 | ||
f9896bf3 | 2960 | ret = print_trace_line(iter); |
2c4f035f | 2961 | if (ret == TRACE_TYPE_PARTIAL_LINE) { |
088b1e42 SR |
2962 | /* don't print partial lines */ |
2963 | iter->seq.len = len; | |
b3806b43 | 2964 | break; |
088b1e42 | 2965 | } |
b91facc3 FW |
2966 | if (ret != TRACE_TYPE_NO_CONSUME) |
2967 | trace_consume(iter); | |
b3806b43 SR |
2968 | |
2969 | if (iter->seq.len >= cnt) | |
2970 | break; | |
b3806b43 | 2971 | } |
4f535968 | 2972 | trace_event_read_unlock(); |
b3806b43 | 2973 | |
b3806b43 | 2974 | /* Now copy what we have to the user */ |
6c6c2796 PP |
2975 | sret = trace_seq_to_user(&iter->seq, ubuf, cnt); |
2976 | if (iter->seq.readpos >= iter->seq.len) | |
f9520750 | 2977 | trace_seq_init(&iter->seq); |
9ff4b974 PP |
2978 | |
2979 | /* | |
2980 | * If there was nothing to send to user, inspite of consuming trace | |
2981 | * entries, go back to wait for more entries. | |
2982 | */ | |
6c6c2796 | 2983 | if (sret == -EBUSY) |
9ff4b974 | 2984 | goto waitagain; |
b3806b43 | 2985 | |
107bad8b | 2986 | out: |
d7350c3f | 2987 | mutex_unlock(&iter->mutex); |
107bad8b | 2988 | |
6c6c2796 | 2989 | return sret; |
b3806b43 SR |
2990 | } |
2991 | ||
3c56819b EGM |
2992 | static void tracing_pipe_buf_release(struct pipe_inode_info *pipe, |
2993 | struct pipe_buffer *buf) | |
2994 | { | |
2995 | __free_page(buf->page); | |
2996 | } | |
2997 | ||
2998 | static void tracing_spd_release_pipe(struct splice_pipe_desc *spd, | |
2999 | unsigned int idx) | |
3000 | { | |
3001 | __free_page(spd->pages[idx]); | |
3002 | } | |
3003 | ||
3004 | static struct pipe_buf_operations tracing_pipe_buf_ops = { | |
34cd4998 SR |
3005 | .can_merge = 0, |
3006 | .map = generic_pipe_buf_map, | |
3007 | .unmap = generic_pipe_buf_unmap, | |
3008 | .confirm = generic_pipe_buf_confirm, | |
3009 | .release = tracing_pipe_buf_release, | |
3010 | .steal = generic_pipe_buf_steal, | |
3011 | .get = generic_pipe_buf_get, | |
3c56819b EGM |
3012 | }; |
3013 | ||
34cd4998 | 3014 | static size_t |
fa7c7f6e | 3015 | tracing_fill_pipe_page(size_t rem, struct trace_iterator *iter) |
34cd4998 SR |
3016 | { |
3017 | size_t count; | |
3018 | int ret; | |
3019 | ||
3020 | /* Seq buffer is page-sized, exactly what we need. */ | |
3021 | for (;;) { | |
3022 | count = iter->seq.len; | |
3023 | ret = print_trace_line(iter); | |
3024 | count = iter->seq.len - count; | |
3025 | if (rem < count) { | |
3026 | rem = 0; | |
3027 | iter->seq.len -= count; | |
3028 | break; | |
3029 | } | |
3030 | if (ret == TRACE_TYPE_PARTIAL_LINE) { | |
3031 | iter->seq.len -= count; | |
3032 | break; | |
3033 | } | |
3034 | ||
74e7ff8c LJ |
3035 | if (ret != TRACE_TYPE_NO_CONSUME) |
3036 | trace_consume(iter); | |
34cd4998 SR |
3037 | rem -= count; |
3038 | if (!find_next_entry_inc(iter)) { | |
3039 | rem = 0; | |
3040 | iter->ent = NULL; | |
3041 | break; | |
3042 | } | |
3043 | } | |
3044 | ||
3045 | return rem; | |
3046 | } | |
3047 | ||
3c56819b EGM |
3048 | static ssize_t tracing_splice_read_pipe(struct file *filp, |
3049 | loff_t *ppos, | |
3050 | struct pipe_inode_info *pipe, | |
3051 | size_t len, | |
3052 | unsigned int flags) | |
3053 | { | |
3054 | struct page *pages[PIPE_BUFFERS]; | |
3055 | struct partial_page partial[PIPE_BUFFERS]; | |
3056 | struct trace_iterator *iter = filp->private_data; | |
3057 | struct splice_pipe_desc spd = { | |
34cd4998 SR |
3058 | .pages = pages, |
3059 | .partial = partial, | |
3060 | .nr_pages = 0, /* This gets updated below. */ | |
3061 | .flags = flags, | |
3062 | .ops = &tracing_pipe_buf_ops, | |
3063 | .spd_release = tracing_spd_release_pipe, | |
3c56819b | 3064 | }; |
d7350c3f | 3065 | static struct tracer *old_tracer; |
3c56819b | 3066 | ssize_t ret; |
34cd4998 | 3067 | size_t rem; |
3c56819b EGM |
3068 | unsigned int i; |
3069 | ||
d7350c3f | 3070 | /* copy the tracer to avoid using a global lock all around */ |
3c56819b | 3071 | mutex_lock(&trace_types_lock); |
d7350c3f FW |
3072 | if (unlikely(old_tracer != current_trace && current_trace)) { |
3073 | old_tracer = current_trace; | |
3074 | *iter->trace = *current_trace; | |
3075 | } | |
3076 | mutex_unlock(&trace_types_lock); | |
3077 | ||
3078 | mutex_lock(&iter->mutex); | |
3c56819b EGM |
3079 | |
3080 | if (iter->trace->splice_read) { | |
3081 | ret = iter->trace->splice_read(iter, filp, | |
3082 | ppos, pipe, len, flags); | |
3083 | if (ret) | |
34cd4998 | 3084 | goto out_err; |
3c56819b EGM |
3085 | } |
3086 | ||
3087 | ret = tracing_wait_pipe(filp); | |
3088 | if (ret <= 0) | |
34cd4998 | 3089 | goto out_err; |
3c56819b EGM |
3090 | |
3091 | if (!iter->ent && !find_next_entry_inc(iter)) { | |
3092 | ret = -EFAULT; | |
34cd4998 | 3093 | goto out_err; |
3c56819b EGM |
3094 | } |
3095 | ||
4f535968 LJ |
3096 | trace_event_read_lock(); |
3097 | ||
3c56819b EGM |
3098 | /* Fill as many pages as possible. */ |
3099 | for (i = 0, rem = len; i < PIPE_BUFFERS && rem; i++) { | |
3100 | pages[i] = alloc_page(GFP_KERNEL); | |
34cd4998 SR |
3101 | if (!pages[i]) |
3102 | break; | |
3c56819b | 3103 | |
fa7c7f6e | 3104 | rem = tracing_fill_pipe_page(rem, iter); |
3c56819b EGM |
3105 | |
3106 | /* Copy the data into the page, so we can start over. */ | |
3107 | ret = trace_seq_to_buffer(&iter->seq, | |
3108 | page_address(pages[i]), | |
3109 | iter->seq.len); | |
3110 | if (ret < 0) { | |
3111 | __free_page(pages[i]); | |
3112 | break; | |
3113 | } | |
3114 | partial[i].offset = 0; | |
3115 | partial[i].len = iter->seq.len; | |
3116 | ||
f9520750 | 3117 | trace_seq_init(&iter->seq); |
3c56819b EGM |
3118 | } |
3119 | ||
4f535968 | 3120 | trace_event_read_unlock(); |
d7350c3f | 3121 | mutex_unlock(&iter->mutex); |
3c56819b EGM |
3122 | |
3123 | spd.nr_pages = i; | |
3124 | ||
3125 | return splice_to_pipe(pipe, &spd); | |
3126 | ||
34cd4998 | 3127 | out_err: |
d7350c3f | 3128 | mutex_unlock(&iter->mutex); |
3c56819b EGM |
3129 | |
3130 | return ret; | |
3131 | } | |
3132 | ||
a98a3c3f SR |
3133 | static ssize_t |
3134 | tracing_entries_read(struct file *filp, char __user *ubuf, | |
3135 | size_t cnt, loff_t *ppos) | |
3136 | { | |
3137 | struct trace_array *tr = filp->private_data; | |
db526ca3 | 3138 | char buf[96]; |
a98a3c3f SR |
3139 | int r; |
3140 | ||
db526ca3 SR |
3141 | mutex_lock(&trace_types_lock); |
3142 | if (!ring_buffer_expanded) | |
3143 | r = sprintf(buf, "%lu (expanded: %lu)\n", | |
3144 | tr->entries >> 10, | |
3145 | trace_buf_size >> 10); | |
3146 | else | |
3147 | r = sprintf(buf, "%lu\n", tr->entries >> 10); | |
3148 | mutex_unlock(&trace_types_lock); | |
3149 | ||
a98a3c3f SR |
3150 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, r); |
3151 | } | |
3152 | ||
3153 | static ssize_t | |
3154 | tracing_entries_write(struct file *filp, const char __user *ubuf, | |
3155 | size_t cnt, loff_t *ppos) | |
3156 | { | |
3157 | unsigned long val; | |
3158 | char buf[64]; | |
bf5e6519 | 3159 | int ret, cpu; |
a98a3c3f | 3160 | |
cffae437 SR |
3161 | if (cnt >= sizeof(buf)) |
3162 | return -EINVAL; | |
a98a3c3f SR |
3163 | |
3164 | if (copy_from_user(&buf, ubuf, cnt)) | |
3165 | return -EFAULT; | |
3166 | ||
3167 | buf[cnt] = 0; | |
3168 | ||
c6caeeb1 SR |
3169 | ret = strict_strtoul(buf, 10, &val); |
3170 | if (ret < 0) | |
3171 | return ret; | |
a98a3c3f SR |
3172 | |
3173 | /* must have at least 1 entry */ | |
3174 | if (!val) | |
3175 | return -EINVAL; | |
3176 | ||
3177 | mutex_lock(&trace_types_lock); | |
3178 | ||
c76f0694 | 3179 | tracing_stop(); |
a98a3c3f | 3180 | |
bf5e6519 SR |
3181 | /* disable all cpu buffers */ |
3182 | for_each_tracing_cpu(cpu) { | |
3183 | if (global_trace.data[cpu]) | |
3184 | atomic_inc(&global_trace.data[cpu]->disabled); | |
3185 | if (max_tr.data[cpu]) | |
3186 | atomic_inc(&max_tr.data[cpu]->disabled); | |
3187 | } | |
3188 | ||
1696b2b0 SR |
3189 | /* value is in KB */ |
3190 | val <<= 10; | |
3191 | ||
3928a8a2 | 3192 | if (val != global_trace.entries) { |
73c5162a | 3193 | ret = tracing_resize_ring_buffer(val); |
3928a8a2 SR |
3194 | if (ret < 0) { |
3195 | cnt = ret; | |
3eefae99 SR |
3196 | goto out; |
3197 | } | |
a98a3c3f SR |
3198 | } |
3199 | ||
3200 | filp->f_pos += cnt; | |
3201 | ||
19384c03 SR |
3202 | /* If check pages failed, return ENOMEM */ |
3203 | if (tracing_disabled) | |
3204 | cnt = -ENOMEM; | |
a98a3c3f | 3205 | out: |
bf5e6519 SR |
3206 | for_each_tracing_cpu(cpu) { |
3207 | if (global_trace.data[cpu]) | |
3208 | atomic_dec(&global_trace.data[cpu]->disabled); | |
3209 | if (max_tr.data[cpu]) | |
3210 | atomic_dec(&max_tr.data[cpu]->disabled); | |
3211 | } | |
3212 | ||
c76f0694 | 3213 | tracing_start(); |
a98a3c3f SR |
3214 | max_tr.entries = global_trace.entries; |
3215 | mutex_unlock(&trace_types_lock); | |
3216 | ||
3217 | return cnt; | |
3218 | } | |
3219 | ||
5bf9a1ee PP |
3220 | static int mark_printk(const char *fmt, ...) |
3221 | { | |
3222 | int ret; | |
3223 | va_list args; | |
3224 | va_start(args, fmt); | |
40ce74f1 | 3225 | ret = trace_vprintk(0, fmt, args); |
5bf9a1ee PP |
3226 | va_end(args); |
3227 | return ret; | |
3228 | } | |
3229 | ||
3230 | static ssize_t | |
3231 | tracing_mark_write(struct file *filp, const char __user *ubuf, | |
3232 | size_t cnt, loff_t *fpos) | |
3233 | { | |
3234 | char *buf; | |
3235 | char *end; | |
5bf9a1ee | 3236 | |
c76f0694 | 3237 | if (tracing_disabled) |
5bf9a1ee PP |
3238 | return -EINVAL; |
3239 | ||
3240 | if (cnt > TRACE_BUF_SIZE) | |
3241 | cnt = TRACE_BUF_SIZE; | |
3242 | ||
3243 | buf = kmalloc(cnt + 1, GFP_KERNEL); | |
3244 | if (buf == NULL) | |
3245 | return -ENOMEM; | |
3246 | ||
3247 | if (copy_from_user(buf, ubuf, cnt)) { | |
3248 | kfree(buf); | |
3249 | return -EFAULT; | |
3250 | } | |
3251 | ||
3252 | /* Cut from the first nil or newline. */ | |
3253 | buf[cnt] = '\0'; | |
3254 | end = strchr(buf, '\n'); | |
3255 | if (end) | |
3256 | *end = '\0'; | |
3257 | ||
3258 | cnt = mark_printk("%s\n", buf); | |
3259 | kfree(buf); | |
3260 | *fpos += cnt; | |
3261 | ||
3262 | return cnt; | |
3263 | } | |
3264 | ||
5079f326 Z |
3265 | static ssize_t tracing_clock_read(struct file *filp, char __user *ubuf, |
3266 | size_t cnt, loff_t *ppos) | |
3267 | { | |
3268 | char buf[64]; | |
3269 | int bufiter = 0; | |
3270 | int i; | |
3271 | ||
3272 | for (i = 0; i < ARRAY_SIZE(trace_clocks); i++) | |
3273 | bufiter += snprintf(buf + bufiter, sizeof(buf) - bufiter, | |
3274 | "%s%s%s%s", i ? " " : "", | |
3275 | i == trace_clock_id ? "[" : "", trace_clocks[i].name, | |
3276 | i == trace_clock_id ? "]" : ""); | |
3277 | bufiter += snprintf(buf + bufiter, sizeof(buf) - bufiter, "\n"); | |
3278 | ||
3279 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, bufiter); | |
3280 | } | |
3281 | ||
3282 | static ssize_t tracing_clock_write(struct file *filp, const char __user *ubuf, | |
3283 | size_t cnt, loff_t *fpos) | |
3284 | { | |
3285 | char buf[64]; | |
3286 | const char *clockstr; | |
3287 | int i; | |
3288 | ||
3289 | if (cnt >= sizeof(buf)) | |
3290 | return -EINVAL; | |
3291 | ||
3292 | if (copy_from_user(&buf, ubuf, cnt)) | |
3293 | return -EFAULT; | |
3294 | ||
3295 | buf[cnt] = 0; | |
3296 | ||
3297 | clockstr = strstrip(buf); | |
3298 | ||
3299 | for (i = 0; i < ARRAY_SIZE(trace_clocks); i++) { | |
3300 | if (strcmp(trace_clocks[i].name, clockstr) == 0) | |
3301 | break; | |
3302 | } | |
3303 | if (i == ARRAY_SIZE(trace_clocks)) | |
3304 | return -EINVAL; | |
3305 | ||
3306 | trace_clock_id = i; | |
3307 | ||
3308 | mutex_lock(&trace_types_lock); | |
3309 | ||
3310 | ring_buffer_set_clock(global_trace.buffer, trace_clocks[i].func); | |
3311 | if (max_tr.buffer) | |
3312 | ring_buffer_set_clock(max_tr.buffer, trace_clocks[i].func); | |
3313 | ||
3314 | mutex_unlock(&trace_types_lock); | |
3315 | ||
3316 | *fpos += cnt; | |
3317 | ||
3318 | return cnt; | |
3319 | } | |
3320 | ||
5e2336a0 | 3321 | static const struct file_operations tracing_max_lat_fops = { |
4bf39a94 IM |
3322 | .open = tracing_open_generic, |
3323 | .read = tracing_max_lat_read, | |
3324 | .write = tracing_max_lat_write, | |
bc0c38d1 SR |
3325 | }; |
3326 | ||
5e2336a0 | 3327 | static const struct file_operations tracing_ctrl_fops = { |
4bf39a94 IM |
3328 | .open = tracing_open_generic, |
3329 | .read = tracing_ctrl_read, | |
3330 | .write = tracing_ctrl_write, | |
bc0c38d1 SR |
3331 | }; |
3332 | ||
5e2336a0 | 3333 | static const struct file_operations set_tracer_fops = { |
4bf39a94 IM |
3334 | .open = tracing_open_generic, |
3335 | .read = tracing_set_trace_read, | |
3336 | .write = tracing_set_trace_write, | |
bc0c38d1 SR |
3337 | }; |
3338 | ||
5e2336a0 | 3339 | static const struct file_operations tracing_pipe_fops = { |
4bf39a94 | 3340 | .open = tracing_open_pipe, |
2a2cc8f7 | 3341 | .poll = tracing_poll_pipe, |
4bf39a94 | 3342 | .read = tracing_read_pipe, |
3c56819b | 3343 | .splice_read = tracing_splice_read_pipe, |
4bf39a94 | 3344 | .release = tracing_release_pipe, |
b3806b43 SR |
3345 | }; |
3346 | ||
5e2336a0 | 3347 | static const struct file_operations tracing_entries_fops = { |
a98a3c3f SR |
3348 | .open = tracing_open_generic, |
3349 | .read = tracing_entries_read, | |
3350 | .write = tracing_entries_write, | |
3351 | }; | |
3352 | ||
5e2336a0 | 3353 | static const struct file_operations tracing_mark_fops = { |
43a15386 | 3354 | .open = tracing_open_generic, |
5bf9a1ee PP |
3355 | .write = tracing_mark_write, |
3356 | }; | |
3357 | ||
5079f326 Z |
3358 | static const struct file_operations trace_clock_fops = { |
3359 | .open = tracing_open_generic, | |
3360 | .read = tracing_clock_read, | |
3361 | .write = tracing_clock_write, | |
3362 | }; | |
3363 | ||
2cadf913 SR |
3364 | struct ftrace_buffer_info { |
3365 | struct trace_array *tr; | |
3366 | void *spare; | |
3367 | int cpu; | |
3368 | unsigned int read; | |
3369 | }; | |
3370 | ||
3371 | static int tracing_buffers_open(struct inode *inode, struct file *filp) | |
3372 | { | |
3373 | int cpu = (int)(long)inode->i_private; | |
3374 | struct ftrace_buffer_info *info; | |
3375 | ||
3376 | if (tracing_disabled) | |
3377 | return -ENODEV; | |
3378 | ||
3379 | info = kzalloc(sizeof(*info), GFP_KERNEL); | |
3380 | if (!info) | |
3381 | return -ENOMEM; | |
3382 | ||
3383 | info->tr = &global_trace; | |
3384 | info->cpu = cpu; | |
ddd538f3 | 3385 | info->spare = NULL; |
2cadf913 SR |
3386 | /* Force reading ring buffer for first read */ |
3387 | info->read = (unsigned int)-1; | |
2cadf913 SR |
3388 | |
3389 | filp->private_data = info; | |
3390 | ||
d1e7e02f | 3391 | return nonseekable_open(inode, filp); |
2cadf913 SR |
3392 | } |
3393 | ||
3394 | static ssize_t | |
3395 | tracing_buffers_read(struct file *filp, char __user *ubuf, | |
3396 | size_t count, loff_t *ppos) | |
3397 | { | |
3398 | struct ftrace_buffer_info *info = filp->private_data; | |
3399 | unsigned int pos; | |
3400 | ssize_t ret; | |
3401 | size_t size; | |
3402 | ||
2dc5d12b SR |
3403 | if (!count) |
3404 | return 0; | |
3405 | ||
ddd538f3 LJ |
3406 | if (!info->spare) |
3407 | info->spare = ring_buffer_alloc_read_page(info->tr->buffer); | |
3408 | if (!info->spare) | |
3409 | return -ENOMEM; | |
3410 | ||
2cadf913 SR |
3411 | /* Do we have previous read data to read? */ |
3412 | if (info->read < PAGE_SIZE) | |
3413 | goto read; | |
3414 | ||
3415 | info->read = 0; | |
3416 | ||
3417 | ret = ring_buffer_read_page(info->tr->buffer, | |
3418 | &info->spare, | |
3419 | count, | |
3420 | info->cpu, 0); | |
3421 | if (ret < 0) | |
3422 | return 0; | |
3423 | ||
3424 | pos = ring_buffer_page_len(info->spare); | |
3425 | ||
3426 | if (pos < PAGE_SIZE) | |
3427 | memset(info->spare + pos, 0, PAGE_SIZE - pos); | |
3428 | ||
3429 | read: | |
3430 | size = PAGE_SIZE - info->read; | |
3431 | if (size > count) | |
3432 | size = count; | |
3433 | ||
3434 | ret = copy_to_user(ubuf, info->spare + info->read, size); | |
2dc5d12b | 3435 | if (ret == size) |
2cadf913 | 3436 | return -EFAULT; |
2dc5d12b SR |
3437 | size -= ret; |
3438 | ||
2cadf913 SR |
3439 | *ppos += size; |
3440 | info->read += size; | |
3441 | ||
3442 | return size; | |
3443 | } | |
3444 | ||
3445 | static int tracing_buffers_release(struct inode *inode, struct file *file) | |
3446 | { | |
3447 | struct ftrace_buffer_info *info = file->private_data; | |
3448 | ||
ddd538f3 LJ |
3449 | if (info->spare) |
3450 | ring_buffer_free_read_page(info->tr->buffer, info->spare); | |
2cadf913 SR |
3451 | kfree(info); |
3452 | ||
3453 | return 0; | |
3454 | } | |
3455 | ||
3456 | struct buffer_ref { | |
3457 | struct ring_buffer *buffer; | |
3458 | void *page; | |
3459 | int ref; | |
3460 | }; | |
3461 | ||
3462 | static void buffer_pipe_buf_release(struct pipe_inode_info *pipe, | |
3463 | struct pipe_buffer *buf) | |
3464 | { | |
3465 | struct buffer_ref *ref = (struct buffer_ref *)buf->private; | |
3466 | ||
3467 | if (--ref->ref) | |
3468 | return; | |
3469 | ||
3470 | ring_buffer_free_read_page(ref->buffer, ref->page); | |
3471 | kfree(ref); | |
3472 | buf->private = 0; | |
3473 | } | |
3474 | ||
3475 | static int buffer_pipe_buf_steal(struct pipe_inode_info *pipe, | |
3476 | struct pipe_buffer *buf) | |
3477 | { | |
3478 | return 1; | |
3479 | } | |
3480 | ||
3481 | static void buffer_pipe_buf_get(struct pipe_inode_info *pipe, | |
3482 | struct pipe_buffer *buf) | |
3483 | { | |
3484 | struct buffer_ref *ref = (struct buffer_ref *)buf->private; | |
3485 | ||
3486 | ref->ref++; | |
3487 | } | |
3488 | ||
3489 | /* Pipe buffer operations for a buffer. */ | |
3490 | static struct pipe_buf_operations buffer_pipe_buf_ops = { | |
3491 | .can_merge = 0, | |
3492 | .map = generic_pipe_buf_map, | |
3493 | .unmap = generic_pipe_buf_unmap, | |
3494 | .confirm = generic_pipe_buf_confirm, | |
3495 | .release = buffer_pipe_buf_release, | |
3496 | .steal = buffer_pipe_buf_steal, | |
3497 | .get = buffer_pipe_buf_get, | |
3498 | }; | |
3499 | ||
3500 | /* | |
3501 | * Callback from splice_to_pipe(), if we need to release some pages | |
3502 | * at the end of the spd in case we error'ed out in filling the pipe. | |
3503 | */ | |
3504 | static void buffer_spd_release(struct splice_pipe_desc *spd, unsigned int i) | |
3505 | { | |
3506 | struct buffer_ref *ref = | |
3507 | (struct buffer_ref *)spd->partial[i].private; | |
3508 | ||
3509 | if (--ref->ref) | |
3510 | return; | |
3511 | ||
3512 | ring_buffer_free_read_page(ref->buffer, ref->page); | |
3513 | kfree(ref); | |
3514 | spd->partial[i].private = 0; | |
3515 | } | |
3516 | ||
3517 | static ssize_t | |
3518 | tracing_buffers_splice_read(struct file *file, loff_t *ppos, | |
3519 | struct pipe_inode_info *pipe, size_t len, | |
3520 | unsigned int flags) | |
3521 | { | |
3522 | struct ftrace_buffer_info *info = file->private_data; | |
3523 | struct partial_page partial[PIPE_BUFFERS]; | |
3524 | struct page *pages[PIPE_BUFFERS]; | |
3525 | struct splice_pipe_desc spd = { | |
3526 | .pages = pages, | |
3527 | .partial = partial, | |
3528 | .flags = flags, | |
3529 | .ops = &buffer_pipe_buf_ops, | |
3530 | .spd_release = buffer_spd_release, | |
3531 | }; | |
3532 | struct buffer_ref *ref; | |
93459c6c | 3533 | int entries, size, i; |
2cadf913 SR |
3534 | size_t ret; |
3535 | ||
93cfb3c9 LJ |
3536 | if (*ppos & (PAGE_SIZE - 1)) { |
3537 | WARN_ONCE(1, "Ftrace: previous read must page-align\n"); | |
3538 | return -EINVAL; | |
3539 | } | |
3540 | ||
3541 | if (len & (PAGE_SIZE - 1)) { | |
3542 | WARN_ONCE(1, "Ftrace: splice_read should page-align\n"); | |
3543 | if (len < PAGE_SIZE) | |
3544 | return -EINVAL; | |
3545 | len &= PAGE_MASK; | |
3546 | } | |
3547 | ||
93459c6c SR |
3548 | entries = ring_buffer_entries_cpu(info->tr->buffer, info->cpu); |
3549 | ||
3550 | for (i = 0; i < PIPE_BUFFERS && len && entries; i++, len -= PAGE_SIZE) { | |
2cadf913 SR |
3551 | struct page *page; |
3552 | int r; | |
3553 | ||
3554 | ref = kzalloc(sizeof(*ref), GFP_KERNEL); | |
3555 | if (!ref) | |
3556 | break; | |
3557 | ||
7267fa68 | 3558 | ref->ref = 1; |
2cadf913 SR |
3559 | ref->buffer = info->tr->buffer; |
3560 | ref->page = ring_buffer_alloc_read_page(ref->buffer); | |
3561 | if (!ref->page) { | |
3562 | kfree(ref); | |
3563 | break; | |
3564 | } | |
3565 | ||
3566 | r = ring_buffer_read_page(ref->buffer, &ref->page, | |
f2957f1f | 3567 | len, info->cpu, 1); |
2cadf913 SR |
3568 | if (r < 0) { |
3569 | ring_buffer_free_read_page(ref->buffer, | |
3570 | ref->page); | |
3571 | kfree(ref); | |
3572 | break; | |
3573 | } | |
3574 | ||
3575 | /* | |
3576 | * zero out any left over data, this is going to | |
3577 | * user land. | |
3578 | */ | |
3579 | size = ring_buffer_page_len(ref->page); | |
3580 | if (size < PAGE_SIZE) | |
3581 | memset(ref->page + size, 0, PAGE_SIZE - size); | |
3582 | ||
3583 | page = virt_to_page(ref->page); | |
3584 | ||
3585 | spd.pages[i] = page; | |
3586 | spd.partial[i].len = PAGE_SIZE; | |
3587 | spd.partial[i].offset = 0; | |
3588 | spd.partial[i].private = (unsigned long)ref; | |
3589 | spd.nr_pages++; | |
93cfb3c9 | 3590 | *ppos += PAGE_SIZE; |
93459c6c SR |
3591 | |
3592 | entries = ring_buffer_entries_cpu(info->tr->buffer, info->cpu); | |
2cadf913 SR |
3593 | } |
3594 | ||
3595 | spd.nr_pages = i; | |
3596 | ||
3597 | /* did we read anything? */ | |
3598 | if (!spd.nr_pages) { | |
3599 | if (flags & SPLICE_F_NONBLOCK) | |
3600 | ret = -EAGAIN; | |
3601 | else | |
3602 | ret = 0; | |
3603 | /* TODO: block */ | |
3604 | return ret; | |
3605 | } | |
3606 | ||
3607 | ret = splice_to_pipe(pipe, &spd); | |
3608 | ||
3609 | return ret; | |
3610 | } | |
3611 | ||
3612 | static const struct file_operations tracing_buffers_fops = { | |
3613 | .open = tracing_buffers_open, | |
3614 | .read = tracing_buffers_read, | |
3615 | .release = tracing_buffers_release, | |
3616 | .splice_read = tracing_buffers_splice_read, | |
3617 | .llseek = no_llseek, | |
3618 | }; | |
3619 | ||
c8d77183 SR |
3620 | static ssize_t |
3621 | tracing_stats_read(struct file *filp, char __user *ubuf, | |
3622 | size_t count, loff_t *ppos) | |
3623 | { | |
3624 | unsigned long cpu = (unsigned long)filp->private_data; | |
3625 | struct trace_array *tr = &global_trace; | |
3626 | struct trace_seq *s; | |
3627 | unsigned long cnt; | |
3628 | ||
e4f2d10f | 3629 | s = kmalloc(sizeof(*s), GFP_KERNEL); |
c8d77183 SR |
3630 | if (!s) |
3631 | return ENOMEM; | |
3632 | ||
3633 | trace_seq_init(s); | |
3634 | ||
3635 | cnt = ring_buffer_entries_cpu(tr->buffer, cpu); | |
3636 | trace_seq_printf(s, "entries: %ld\n", cnt); | |
3637 | ||
3638 | cnt = ring_buffer_overrun_cpu(tr->buffer, cpu); | |
3639 | trace_seq_printf(s, "overrun: %ld\n", cnt); | |
3640 | ||
3641 | cnt = ring_buffer_commit_overrun_cpu(tr->buffer, cpu); | |
3642 | trace_seq_printf(s, "commit overrun: %ld\n", cnt); | |
3643 | ||
c8d77183 SR |
3644 | count = simple_read_from_buffer(ubuf, count, ppos, s->buffer, s->len); |
3645 | ||
3646 | kfree(s); | |
3647 | ||
3648 | return count; | |
3649 | } | |
3650 | ||
3651 | static const struct file_operations tracing_stats_fops = { | |
3652 | .open = tracing_open_generic, | |
3653 | .read = tracing_stats_read, | |
3654 | }; | |
3655 | ||
bc0c38d1 SR |
3656 | #ifdef CONFIG_DYNAMIC_FTRACE |
3657 | ||
b807c3d0 SR |
3658 | int __weak ftrace_arch_read_dyn_info(char *buf, int size) |
3659 | { | |
3660 | return 0; | |
3661 | } | |
3662 | ||
bc0c38d1 | 3663 | static ssize_t |
b807c3d0 | 3664 | tracing_read_dyn_info(struct file *filp, char __user *ubuf, |
bc0c38d1 SR |
3665 | size_t cnt, loff_t *ppos) |
3666 | { | |
a26a2a27 SR |
3667 | static char ftrace_dyn_info_buffer[1024]; |
3668 | static DEFINE_MUTEX(dyn_info_mutex); | |
bc0c38d1 | 3669 | unsigned long *p = filp->private_data; |
b807c3d0 | 3670 | char *buf = ftrace_dyn_info_buffer; |
a26a2a27 | 3671 | int size = ARRAY_SIZE(ftrace_dyn_info_buffer); |
bc0c38d1 SR |
3672 | int r; |
3673 | ||
b807c3d0 SR |
3674 | mutex_lock(&dyn_info_mutex); |
3675 | r = sprintf(buf, "%ld ", *p); | |
4bf39a94 | 3676 | |
a26a2a27 | 3677 | r += ftrace_arch_read_dyn_info(buf+r, (size-1)-r); |
b807c3d0 SR |
3678 | buf[r++] = '\n'; |
3679 | ||
3680 | r = simple_read_from_buffer(ubuf, cnt, ppos, buf, r); | |
3681 | ||
3682 | mutex_unlock(&dyn_info_mutex); | |
3683 | ||
3684 | return r; | |
bc0c38d1 SR |
3685 | } |
3686 | ||
5e2336a0 | 3687 | static const struct file_operations tracing_dyn_info_fops = { |
4bf39a94 | 3688 | .open = tracing_open_generic, |
b807c3d0 | 3689 | .read = tracing_read_dyn_info, |
bc0c38d1 SR |
3690 | }; |
3691 | #endif | |
3692 | ||
3693 | static struct dentry *d_tracer; | |
3694 | ||
3695 | struct dentry *tracing_init_dentry(void) | |
3696 | { | |
3697 | static int once; | |
3698 | ||
3699 | if (d_tracer) | |
3700 | return d_tracer; | |
3701 | ||
3e1f60b8 FW |
3702 | if (!debugfs_initialized()) |
3703 | return NULL; | |
3704 | ||
bc0c38d1 SR |
3705 | d_tracer = debugfs_create_dir("tracing", NULL); |
3706 | ||
3707 | if (!d_tracer && !once) { | |
3708 | once = 1; | |
3709 | pr_warning("Could not create debugfs directory 'tracing'\n"); | |
3710 | return NULL; | |
3711 | } | |
3712 | ||
3713 | return d_tracer; | |
3714 | } | |
3715 | ||
b04cc6b1 FW |
3716 | static struct dentry *d_percpu; |
3717 | ||
3718 | struct dentry *tracing_dentry_percpu(void) | |
3719 | { | |
3720 | static int once; | |
3721 | struct dentry *d_tracer; | |
3722 | ||
3723 | if (d_percpu) | |
3724 | return d_percpu; | |
3725 | ||
3726 | d_tracer = tracing_init_dentry(); | |
3727 | ||
3728 | if (!d_tracer) | |
3729 | return NULL; | |
3730 | ||
3731 | d_percpu = debugfs_create_dir("per_cpu", d_tracer); | |
3732 | ||
3733 | if (!d_percpu && !once) { | |
3734 | once = 1; | |
3735 | pr_warning("Could not create debugfs directory 'per_cpu'\n"); | |
3736 | return NULL; | |
3737 | } | |
3738 | ||
3739 | return d_percpu; | |
3740 | } | |
3741 | ||
3742 | static void tracing_init_debugfs_percpu(long cpu) | |
3743 | { | |
3744 | struct dentry *d_percpu = tracing_dentry_percpu(); | |
5452af66 | 3745 | struct dentry *d_cpu; |
8656e7a2 FW |
3746 | /* strlen(cpu) + MAX(log10(cpu)) + '\0' */ |
3747 | char cpu_dir[7]; | |
b04cc6b1 FW |
3748 | |
3749 | if (cpu > 999 || cpu < 0) | |
3750 | return; | |
3751 | ||
8656e7a2 FW |
3752 | sprintf(cpu_dir, "cpu%ld", cpu); |
3753 | d_cpu = debugfs_create_dir(cpu_dir, d_percpu); | |
3754 | if (!d_cpu) { | |
3755 | pr_warning("Could not create debugfs '%s' entry\n", cpu_dir); | |
3756 | return; | |
3757 | } | |
b04cc6b1 | 3758 | |
8656e7a2 | 3759 | /* per cpu trace_pipe */ |
5452af66 FW |
3760 | trace_create_file("trace_pipe", 0444, d_cpu, |
3761 | (void *) cpu, &tracing_pipe_fops); | |
b04cc6b1 FW |
3762 | |
3763 | /* per cpu trace */ | |
5452af66 FW |
3764 | trace_create_file("trace", 0644, d_cpu, |
3765 | (void *) cpu, &tracing_fops); | |
7f96f93f | 3766 | |
5452af66 FW |
3767 | trace_create_file("trace_pipe_raw", 0444, d_cpu, |
3768 | (void *) cpu, &tracing_buffers_fops); | |
7f96f93f | 3769 | |
c8d77183 SR |
3770 | trace_create_file("stats", 0444, d_cpu, |
3771 | (void *) cpu, &tracing_stats_fops); | |
b04cc6b1 FW |
3772 | } |
3773 | ||
60a11774 SR |
3774 | #ifdef CONFIG_FTRACE_SELFTEST |
3775 | /* Let selftest have access to static functions in this file */ | |
3776 | #include "trace_selftest.c" | |
3777 | #endif | |
3778 | ||
577b785f SR |
3779 | struct trace_option_dentry { |
3780 | struct tracer_opt *opt; | |
3781 | struct tracer_flags *flags; | |
3782 | struct dentry *entry; | |
3783 | }; | |
3784 | ||
3785 | static ssize_t | |
3786 | trace_options_read(struct file *filp, char __user *ubuf, size_t cnt, | |
3787 | loff_t *ppos) | |
3788 | { | |
3789 | struct trace_option_dentry *topt = filp->private_data; | |
3790 | char *buf; | |
3791 | ||
3792 | if (topt->flags->val & topt->opt->bit) | |
3793 | buf = "1\n"; | |
3794 | else | |
3795 | buf = "0\n"; | |
3796 | ||
3797 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, 2); | |
3798 | } | |
3799 | ||
3800 | static ssize_t | |
3801 | trace_options_write(struct file *filp, const char __user *ubuf, size_t cnt, | |
3802 | loff_t *ppos) | |
3803 | { | |
3804 | struct trace_option_dentry *topt = filp->private_data; | |
3805 | unsigned long val; | |
3806 | char buf[64]; | |
3807 | int ret; | |
3808 | ||
3809 | if (cnt >= sizeof(buf)) | |
3810 | return -EINVAL; | |
3811 | ||
3812 | if (copy_from_user(&buf, ubuf, cnt)) | |
3813 | return -EFAULT; | |
3814 | ||
3815 | buf[cnt] = 0; | |
3816 | ||
3817 | ret = strict_strtoul(buf, 10, &val); | |
3818 | if (ret < 0) | |
3819 | return ret; | |
3820 | ||
3821 | ret = 0; | |
3822 | switch (val) { | |
3823 | case 0: | |
3824 | /* do nothing if already cleared */ | |
3825 | if (!(topt->flags->val & topt->opt->bit)) | |
3826 | break; | |
3827 | ||
3828 | mutex_lock(&trace_types_lock); | |
3829 | if (current_trace->set_flag) | |
3830 | ret = current_trace->set_flag(topt->flags->val, | |
3831 | topt->opt->bit, 0); | |
3832 | mutex_unlock(&trace_types_lock); | |
3833 | if (ret) | |
3834 | return ret; | |
3835 | topt->flags->val &= ~topt->opt->bit; | |
3836 | break; | |
3837 | case 1: | |
3838 | /* do nothing if already set */ | |
3839 | if (topt->flags->val & topt->opt->bit) | |
3840 | break; | |
3841 | ||
3842 | mutex_lock(&trace_types_lock); | |
3843 | if (current_trace->set_flag) | |
3844 | ret = current_trace->set_flag(topt->flags->val, | |
3845 | topt->opt->bit, 1); | |
3846 | mutex_unlock(&trace_types_lock); | |
3847 | if (ret) | |
3848 | return ret; | |
3849 | topt->flags->val |= topt->opt->bit; | |
3850 | break; | |
3851 | ||
3852 | default: | |
3853 | return -EINVAL; | |
3854 | } | |
3855 | ||
3856 | *ppos += cnt; | |
3857 | ||
3858 | return cnt; | |
3859 | } | |
3860 | ||
3861 | ||
3862 | static const struct file_operations trace_options_fops = { | |
3863 | .open = tracing_open_generic, | |
3864 | .read = trace_options_read, | |
3865 | .write = trace_options_write, | |
3866 | }; | |
3867 | ||
a8259075 SR |
3868 | static ssize_t |
3869 | trace_options_core_read(struct file *filp, char __user *ubuf, size_t cnt, | |
3870 | loff_t *ppos) | |
3871 | { | |
3872 | long index = (long)filp->private_data; | |
3873 | char *buf; | |
3874 | ||
3875 | if (trace_flags & (1 << index)) | |
3876 | buf = "1\n"; | |
3877 | else | |
3878 | buf = "0\n"; | |
3879 | ||
3880 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, 2); | |
3881 | } | |
3882 | ||
3883 | static ssize_t | |
3884 | trace_options_core_write(struct file *filp, const char __user *ubuf, size_t cnt, | |
3885 | loff_t *ppos) | |
3886 | { | |
3887 | long index = (long)filp->private_data; | |
3888 | char buf[64]; | |
3889 | unsigned long val; | |
3890 | int ret; | |
3891 | ||
3892 | if (cnt >= sizeof(buf)) | |
3893 | return -EINVAL; | |
3894 | ||
3895 | if (copy_from_user(&buf, ubuf, cnt)) | |
3896 | return -EFAULT; | |
3897 | ||
3898 | buf[cnt] = 0; | |
3899 | ||
3900 | ret = strict_strtoul(buf, 10, &val); | |
3901 | if (ret < 0) | |
3902 | return ret; | |
3903 | ||
f2d84b65 | 3904 | if (val != 0 && val != 1) |
a8259075 | 3905 | return -EINVAL; |
f2d84b65 | 3906 | set_tracer_flags(1 << index, val); |
a8259075 SR |
3907 | |
3908 | *ppos += cnt; | |
3909 | ||
3910 | return cnt; | |
3911 | } | |
3912 | ||
a8259075 SR |
3913 | static const struct file_operations trace_options_core_fops = { |
3914 | .open = tracing_open_generic, | |
3915 | .read = trace_options_core_read, | |
3916 | .write = trace_options_core_write, | |
3917 | }; | |
3918 | ||
5452af66 FW |
3919 | struct dentry *trace_create_file(const char *name, |
3920 | mode_t mode, | |
3921 | struct dentry *parent, | |
3922 | void *data, | |
3923 | const struct file_operations *fops) | |
3924 | { | |
3925 | struct dentry *ret; | |
3926 | ||
3927 | ret = debugfs_create_file(name, mode, parent, data, fops); | |
3928 | if (!ret) | |
3929 | pr_warning("Could not create debugfs '%s' entry\n", name); | |
3930 | ||
3931 | return ret; | |
3932 | } | |
3933 | ||
3934 | ||
a8259075 SR |
3935 | static struct dentry *trace_options_init_dentry(void) |
3936 | { | |
3937 | struct dentry *d_tracer; | |
3938 | static struct dentry *t_options; | |
3939 | ||
3940 | if (t_options) | |
3941 | return t_options; | |
3942 | ||
3943 | d_tracer = tracing_init_dentry(); | |
3944 | if (!d_tracer) | |
3945 | return NULL; | |
3946 | ||
3947 | t_options = debugfs_create_dir("options", d_tracer); | |
3948 | if (!t_options) { | |
3949 | pr_warning("Could not create debugfs directory 'options'\n"); | |
3950 | return NULL; | |
3951 | } | |
3952 | ||
3953 | return t_options; | |
3954 | } | |
3955 | ||
577b785f SR |
3956 | static void |
3957 | create_trace_option_file(struct trace_option_dentry *topt, | |
3958 | struct tracer_flags *flags, | |
3959 | struct tracer_opt *opt) | |
3960 | { | |
3961 | struct dentry *t_options; | |
577b785f SR |
3962 | |
3963 | t_options = trace_options_init_dentry(); | |
3964 | if (!t_options) | |
3965 | return; | |
3966 | ||
3967 | topt->flags = flags; | |
3968 | topt->opt = opt; | |
3969 | ||
5452af66 | 3970 | topt->entry = trace_create_file(opt->name, 0644, t_options, topt, |
577b785f SR |
3971 | &trace_options_fops); |
3972 | ||
577b785f SR |
3973 | } |
3974 | ||
3975 | static struct trace_option_dentry * | |
3976 | create_trace_option_files(struct tracer *tracer) | |
3977 | { | |
3978 | struct trace_option_dentry *topts; | |
3979 | struct tracer_flags *flags; | |
3980 | struct tracer_opt *opts; | |
3981 | int cnt; | |
3982 | ||
3983 | if (!tracer) | |
3984 | return NULL; | |
3985 | ||
3986 | flags = tracer->flags; | |
3987 | ||
3988 | if (!flags || !flags->opts) | |
3989 | return NULL; | |
3990 | ||
3991 | opts = flags->opts; | |
3992 | ||
3993 | for (cnt = 0; opts[cnt].name; cnt++) | |
3994 | ; | |
3995 | ||
0cfe8245 | 3996 | topts = kcalloc(cnt + 1, sizeof(*topts), GFP_KERNEL); |
577b785f SR |
3997 | if (!topts) |
3998 | return NULL; | |
3999 | ||
4000 | for (cnt = 0; opts[cnt].name; cnt++) | |
4001 | create_trace_option_file(&topts[cnt], flags, | |
4002 | &opts[cnt]); | |
4003 | ||
4004 | return topts; | |
4005 | } | |
4006 | ||
4007 | static void | |
4008 | destroy_trace_option_files(struct trace_option_dentry *topts) | |
4009 | { | |
4010 | int cnt; | |
4011 | ||
4012 | if (!topts) | |
4013 | return; | |
4014 | ||
4015 | for (cnt = 0; topts[cnt].opt; cnt++) { | |
4016 | if (topts[cnt].entry) | |
4017 | debugfs_remove(topts[cnt].entry); | |
4018 | } | |
4019 | ||
4020 | kfree(topts); | |
4021 | } | |
4022 | ||
a8259075 SR |
4023 | static struct dentry * |
4024 | create_trace_option_core_file(const char *option, long index) | |
4025 | { | |
4026 | struct dentry *t_options; | |
a8259075 SR |
4027 | |
4028 | t_options = trace_options_init_dentry(); | |
4029 | if (!t_options) | |
4030 | return NULL; | |
4031 | ||
5452af66 | 4032 | return trace_create_file(option, 0644, t_options, (void *)index, |
a8259075 | 4033 | &trace_options_core_fops); |
a8259075 SR |
4034 | } |
4035 | ||
4036 | static __init void create_trace_options_dir(void) | |
4037 | { | |
4038 | struct dentry *t_options; | |
a8259075 SR |
4039 | int i; |
4040 | ||
4041 | t_options = trace_options_init_dentry(); | |
4042 | if (!t_options) | |
4043 | return; | |
4044 | ||
5452af66 FW |
4045 | for (i = 0; trace_options[i]; i++) |
4046 | create_trace_option_core_file(trace_options[i], i); | |
a8259075 SR |
4047 | } |
4048 | ||
b5ad384e | 4049 | static __init int tracer_init_debugfs(void) |
bc0c38d1 SR |
4050 | { |
4051 | struct dentry *d_tracer; | |
b04cc6b1 | 4052 | int cpu; |
bc0c38d1 SR |
4053 | |
4054 | d_tracer = tracing_init_dentry(); | |
4055 | ||
5452af66 FW |
4056 | trace_create_file("tracing_enabled", 0644, d_tracer, |
4057 | &global_trace, &tracing_ctrl_fops); | |
bc0c38d1 | 4058 | |
5452af66 FW |
4059 | trace_create_file("trace_options", 0644, d_tracer, |
4060 | NULL, &tracing_iter_fops); | |
bc0c38d1 | 4061 | |
5452af66 FW |
4062 | trace_create_file("tracing_cpumask", 0644, d_tracer, |
4063 | NULL, &tracing_cpumask_fops); | |
4064 | ||
4065 | trace_create_file("trace", 0644, d_tracer, | |
4066 | (void *) TRACE_PIPE_ALL_CPU, &tracing_fops); | |
a8259075 | 4067 | |
5452af66 FW |
4068 | trace_create_file("available_tracers", 0444, d_tracer, |
4069 | &global_trace, &show_traces_fops); | |
4070 | ||
339ae5d3 | 4071 | trace_create_file("current_tracer", 0644, d_tracer, |
5452af66 FW |
4072 | &global_trace, &set_tracer_fops); |
4073 | ||
5d4a9dba | 4074 | #ifdef CONFIG_TRACER_MAX_TRACE |
5452af66 FW |
4075 | trace_create_file("tracing_max_latency", 0644, d_tracer, |
4076 | &tracing_max_latency, &tracing_max_lat_fops); | |
4077 | ||
4078 | trace_create_file("tracing_thresh", 0644, d_tracer, | |
4079 | &tracing_thresh, &tracing_max_lat_fops); | |
5d4a9dba | 4080 | #endif |
a8259075 | 4081 | |
339ae5d3 | 4082 | trace_create_file("README", 0444, d_tracer, |
5452af66 FW |
4083 | NULL, &tracing_readme_fops); |
4084 | ||
4085 | trace_create_file("trace_pipe", 0444, d_tracer, | |
b04cc6b1 | 4086 | (void *) TRACE_PIPE_ALL_CPU, &tracing_pipe_fops); |
5452af66 FW |
4087 | |
4088 | trace_create_file("buffer_size_kb", 0644, d_tracer, | |
4089 | &global_trace, &tracing_entries_fops); | |
4090 | ||
4091 | trace_create_file("trace_marker", 0220, d_tracer, | |
4092 | NULL, &tracing_mark_fops); | |
5bf9a1ee | 4093 | |
69abe6a5 AP |
4094 | trace_create_file("saved_cmdlines", 0444, d_tracer, |
4095 | NULL, &tracing_saved_cmdlines_fops); | |
5bf9a1ee | 4096 | |
5079f326 Z |
4097 | trace_create_file("trace_clock", 0644, d_tracer, NULL, |
4098 | &trace_clock_fops); | |
4099 | ||
bc0c38d1 | 4100 | #ifdef CONFIG_DYNAMIC_FTRACE |
5452af66 FW |
4101 | trace_create_file("dyn_ftrace_total_info", 0444, d_tracer, |
4102 | &ftrace_update_tot_cnt, &tracing_dyn_info_fops); | |
bc0c38d1 | 4103 | #endif |
d618b3e6 IM |
4104 | #ifdef CONFIG_SYSPROF_TRACER |
4105 | init_tracer_sysprof_debugfs(d_tracer); | |
4106 | #endif | |
b04cc6b1 | 4107 | |
5452af66 FW |
4108 | create_trace_options_dir(); |
4109 | ||
b04cc6b1 FW |
4110 | for_each_tracing_cpu(cpu) |
4111 | tracing_init_debugfs_percpu(cpu); | |
4112 | ||
b5ad384e | 4113 | return 0; |
bc0c38d1 SR |
4114 | } |
4115 | ||
3f5a54e3 SR |
4116 | static int trace_panic_handler(struct notifier_block *this, |
4117 | unsigned long event, void *unused) | |
4118 | { | |
944ac425 SR |
4119 | if (ftrace_dump_on_oops) |
4120 | ftrace_dump(); | |
3f5a54e3 SR |
4121 | return NOTIFY_OK; |
4122 | } | |
4123 | ||
4124 | static struct notifier_block trace_panic_notifier = { | |
4125 | .notifier_call = trace_panic_handler, | |
4126 | .next = NULL, | |
4127 | .priority = 150 /* priority: INT_MAX >= x >= 0 */ | |
4128 | }; | |
4129 | ||
4130 | static int trace_die_handler(struct notifier_block *self, | |
4131 | unsigned long val, | |
4132 | void *data) | |
4133 | { | |
4134 | switch (val) { | |
4135 | case DIE_OOPS: | |
944ac425 SR |
4136 | if (ftrace_dump_on_oops) |
4137 | ftrace_dump(); | |
3f5a54e3 SR |
4138 | break; |
4139 | default: | |
4140 | break; | |
4141 | } | |
4142 | return NOTIFY_OK; | |
4143 | } | |
4144 | ||
4145 | static struct notifier_block trace_die_notifier = { | |
4146 | .notifier_call = trace_die_handler, | |
4147 | .priority = 200 | |
4148 | }; | |
4149 | ||
4150 | /* | |
4151 | * printk is set to max of 1024, we really don't need it that big. | |
4152 | * Nothing should be printing 1000 characters anyway. | |
4153 | */ | |
4154 | #define TRACE_MAX_PRINT 1000 | |
4155 | ||
4156 | /* | |
4157 | * Define here KERN_TRACE so that we have one place to modify | |
4158 | * it if we decide to change what log level the ftrace dump | |
4159 | * should be at. | |
4160 | */ | |
428aee14 | 4161 | #define KERN_TRACE KERN_EMERG |
3f5a54e3 SR |
4162 | |
4163 | static void | |
4164 | trace_printk_seq(struct trace_seq *s) | |
4165 | { | |
4166 | /* Probably should print a warning here. */ | |
4167 | if (s->len >= 1000) | |
4168 | s->len = 1000; | |
4169 | ||
4170 | /* should be zero ended, but we are paranoid. */ | |
4171 | s->buffer[s->len] = 0; | |
4172 | ||
4173 | printk(KERN_TRACE "%s", s->buffer); | |
4174 | ||
f9520750 | 4175 | trace_seq_init(s); |
3f5a54e3 SR |
4176 | } |
4177 | ||
cf586b61 | 4178 | static void __ftrace_dump(bool disable_tracing) |
3f5a54e3 | 4179 | { |
cd891ae0 SR |
4180 | static raw_spinlock_t ftrace_dump_lock = |
4181 | (raw_spinlock_t)__RAW_SPIN_LOCK_UNLOCKED; | |
3f5a54e3 SR |
4182 | /* use static because iter can be a bit big for the stack */ |
4183 | static struct trace_iterator iter; | |
cf586b61 | 4184 | unsigned int old_userobj; |
3f5a54e3 | 4185 | static int dump_ran; |
d769041f SR |
4186 | unsigned long flags; |
4187 | int cnt = 0, cpu; | |
3f5a54e3 SR |
4188 | |
4189 | /* only one dump */ | |
cd891ae0 SR |
4190 | local_irq_save(flags); |
4191 | __raw_spin_lock(&ftrace_dump_lock); | |
3f5a54e3 SR |
4192 | if (dump_ran) |
4193 | goto out; | |
4194 | ||
4195 | dump_ran = 1; | |
4196 | ||
0ee6b6cf | 4197 | tracing_off(); |
cf586b61 FW |
4198 | |
4199 | if (disable_tracing) | |
4200 | ftrace_kill(); | |
3f5a54e3 | 4201 | |
d769041f SR |
4202 | for_each_tracing_cpu(cpu) { |
4203 | atomic_inc(&global_trace.data[cpu]->disabled); | |
4204 | } | |
4205 | ||
cf586b61 FW |
4206 | old_userobj = trace_flags & TRACE_ITER_SYM_USEROBJ; |
4207 | ||
b54d3de9 TE |
4208 | /* don't look at user memory in panic mode */ |
4209 | trace_flags &= ~TRACE_ITER_SYM_USEROBJ; | |
4210 | ||
3f5a54e3 SR |
4211 | printk(KERN_TRACE "Dumping ftrace buffer:\n"); |
4212 | ||
e543ad76 | 4213 | /* Simulate the iterator */ |
3f5a54e3 SR |
4214 | iter.tr = &global_trace; |
4215 | iter.trace = current_trace; | |
e543ad76 | 4216 | iter.cpu_file = TRACE_PIPE_ALL_CPU; |
3f5a54e3 SR |
4217 | |
4218 | /* | |
4219 | * We need to stop all tracing on all CPUS to read the | |
4220 | * the next buffer. This is a bit expensive, but is | |
4221 | * not done often. We fill all what we can read, | |
4222 | * and then release the locks again. | |
4223 | */ | |
4224 | ||
3f5a54e3 SR |
4225 | while (!trace_empty(&iter)) { |
4226 | ||
4227 | if (!cnt) | |
4228 | printk(KERN_TRACE "---------------------------------\n"); | |
4229 | ||
4230 | cnt++; | |
4231 | ||
4232 | /* reset all but tr, trace, and overruns */ | |
4233 | memset(&iter.seq, 0, | |
4234 | sizeof(struct trace_iterator) - | |
4235 | offsetof(struct trace_iterator, seq)); | |
4236 | iter.iter_flags |= TRACE_FILE_LAT_FMT; | |
4237 | iter.pos = -1; | |
4238 | ||
4239 | if (find_next_entry_inc(&iter) != NULL) { | |
74e7ff8c LJ |
4240 | int ret; |
4241 | ||
4242 | ret = print_trace_line(&iter); | |
4243 | if (ret != TRACE_TYPE_NO_CONSUME) | |
4244 | trace_consume(&iter); | |
3f5a54e3 SR |
4245 | } |
4246 | ||
4247 | trace_printk_seq(&iter.seq); | |
4248 | } | |
4249 | ||
4250 | if (!cnt) | |
4251 | printk(KERN_TRACE " (ftrace buffer empty)\n"); | |
4252 | else | |
4253 | printk(KERN_TRACE "---------------------------------\n"); | |
4254 | ||
cf586b61 FW |
4255 | /* Re-enable tracing if requested */ |
4256 | if (!disable_tracing) { | |
4257 | trace_flags |= old_userobj; | |
4258 | ||
4259 | for_each_tracing_cpu(cpu) { | |
4260 | atomic_dec(&global_trace.data[cpu]->disabled); | |
4261 | } | |
4262 | tracing_on(); | |
4263 | } | |
4264 | ||
3f5a54e3 | 4265 | out: |
cd891ae0 SR |
4266 | __raw_spin_unlock(&ftrace_dump_lock); |
4267 | local_irq_restore(flags); | |
3f5a54e3 SR |
4268 | } |
4269 | ||
cf586b61 FW |
4270 | /* By default: disable tracing after the dump */ |
4271 | void ftrace_dump(void) | |
4272 | { | |
4273 | __ftrace_dump(true); | |
4274 | } | |
4275 | ||
3928a8a2 | 4276 | __init static int tracer_alloc_buffers(void) |
bc0c38d1 | 4277 | { |
73c5162a | 4278 | int ring_buf_size; |
4c11d7ae | 4279 | int i; |
9e01c1b7 | 4280 | int ret = -ENOMEM; |
4c11d7ae | 4281 | |
9e01c1b7 RR |
4282 | if (!alloc_cpumask_var(&tracing_buffer_mask, GFP_KERNEL)) |
4283 | goto out; | |
4284 | ||
4285 | if (!alloc_cpumask_var(&tracing_cpumask, GFP_KERNEL)) | |
4286 | goto out_free_buffer_mask; | |
4c11d7ae | 4287 | |
b04cc6b1 FW |
4288 | if (!alloc_cpumask_var(&tracing_reader_cpumask, GFP_KERNEL)) |
4289 | goto out_free_tracing_cpumask; | |
4290 | ||
73c5162a SR |
4291 | /* To save memory, keep the ring buffer size to its minimum */ |
4292 | if (ring_buffer_expanded) | |
4293 | ring_buf_size = trace_buf_size; | |
4294 | else | |
4295 | ring_buf_size = 1; | |
4296 | ||
9e01c1b7 RR |
4297 | cpumask_copy(tracing_buffer_mask, cpu_possible_mask); |
4298 | cpumask_copy(tracing_cpumask, cpu_all_mask); | |
b04cc6b1 | 4299 | cpumask_clear(tracing_reader_cpumask); |
9e01c1b7 RR |
4300 | |
4301 | /* TODO: make the number of buffers hot pluggable with CPUS */ | |
73c5162a | 4302 | global_trace.buffer = ring_buffer_alloc(ring_buf_size, |
3928a8a2 SR |
4303 | TRACE_BUFFER_FLAGS); |
4304 | if (!global_trace.buffer) { | |
4305 | printk(KERN_ERR "tracer: failed to allocate ring buffer!\n"); | |
4306 | WARN_ON(1); | |
9e01c1b7 | 4307 | goto out_free_cpumask; |
4c11d7ae | 4308 | } |
3928a8a2 | 4309 | global_trace.entries = ring_buffer_size(global_trace.buffer); |
4c11d7ae | 4310 | |
9e01c1b7 | 4311 | |
4c11d7ae | 4312 | #ifdef CONFIG_TRACER_MAX_TRACE |
73c5162a | 4313 | max_tr.buffer = ring_buffer_alloc(ring_buf_size, |
3928a8a2 SR |
4314 | TRACE_BUFFER_FLAGS); |
4315 | if (!max_tr.buffer) { | |
4316 | printk(KERN_ERR "tracer: failed to allocate max ring buffer!\n"); | |
4317 | WARN_ON(1); | |
4318 | ring_buffer_free(global_trace.buffer); | |
9e01c1b7 | 4319 | goto out_free_cpumask; |
4c11d7ae | 4320 | } |
3928a8a2 SR |
4321 | max_tr.entries = ring_buffer_size(max_tr.buffer); |
4322 | WARN_ON(max_tr.entries != global_trace.entries); | |
a98a3c3f | 4323 | #endif |
ab46428c | 4324 | |
4c11d7ae | 4325 | /* Allocate the first page for all buffers */ |
ab46428c | 4326 | for_each_tracing_cpu(i) { |
566b0aaf | 4327 | global_trace.data[i] = &per_cpu(global_trace_cpu, i); |
bc0c38d1 | 4328 | max_tr.data[i] = &per_cpu(max_data, i); |
4c11d7ae | 4329 | } |
bc0c38d1 | 4330 | |
bc0c38d1 SR |
4331 | trace_init_cmdlines(); |
4332 | ||
43a15386 | 4333 | register_tracer(&nop_trace); |
79fb0768 | 4334 | current_trace = &nop_trace; |
b5ad384e FW |
4335 | #ifdef CONFIG_BOOT_TRACER |
4336 | register_tracer(&boot_tracer); | |
b5ad384e | 4337 | #endif |
60a11774 SR |
4338 | /* All seems OK, enable tracing */ |
4339 | tracing_disabled = 0; | |
3928a8a2 | 4340 | |
3f5a54e3 SR |
4341 | atomic_notifier_chain_register(&panic_notifier_list, |
4342 | &trace_panic_notifier); | |
4343 | ||
4344 | register_die_notifier(&trace_die_notifier); | |
2fc1dfbe FW |
4345 | |
4346 | return 0; | |
3f5a54e3 | 4347 | |
9e01c1b7 | 4348 | out_free_cpumask: |
b04cc6b1 FW |
4349 | free_cpumask_var(tracing_reader_cpumask); |
4350 | out_free_tracing_cpumask: | |
9e01c1b7 RR |
4351 | free_cpumask_var(tracing_cpumask); |
4352 | out_free_buffer_mask: | |
4353 | free_cpumask_var(tracing_buffer_mask); | |
4354 | out: | |
4355 | return ret; | |
bc0c38d1 | 4356 | } |
b2821ae6 SR |
4357 | |
4358 | __init static int clear_boot_tracer(void) | |
4359 | { | |
4360 | /* | |
4361 | * The default tracer at boot buffer is an init section. | |
4362 | * This function is called in lateinit. If we did not | |
4363 | * find the boot tracer, then clear it out, to prevent | |
4364 | * later registration from accessing the buffer that is | |
4365 | * about to be freed. | |
4366 | */ | |
4367 | if (!default_bootup_tracer) | |
4368 | return 0; | |
4369 | ||
4370 | printk(KERN_INFO "ftrace bootup tracer '%s' not registered.\n", | |
4371 | default_bootup_tracer); | |
4372 | default_bootup_tracer = NULL; | |
4373 | ||
4374 | return 0; | |
4375 | } | |
4376 | ||
b5ad384e FW |
4377 | early_initcall(tracer_alloc_buffers); |
4378 | fs_initcall(tracer_init_debugfs); | |
b2821ae6 | 4379 | late_initcall(clear_boot_tracer); |