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Commit | Line | Data |
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bc0c38d1 SR |
1 | /* |
2 | * ring buffer based function tracer | |
3 | * | |
4 | * Copyright (C) 2007-2008 Steven Rostedt <srostedt@redhat.com> | |
5 | * Copyright (C) 2008 Ingo Molnar <mingo@redhat.com> | |
6 | * | |
7 | * Originally taken from the RT patch by: | |
8 | * Arnaldo Carvalho de Melo <acme@redhat.com> | |
9 | * | |
10 | * Based on code from the latency_tracer, that is: | |
11 | * Copyright (C) 2004-2006 Ingo Molnar | |
12 | * Copyright (C) 2004 William Lee Irwin III | |
13 | */ | |
2cadf913 | 14 | #include <linux/ring_buffer.h> |
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 | ||
d769041f SR |
485 | ftrace_enable_cpu(); |
486 | ||
97b17efe | 487 | WARN_ON_ONCE(ret && ret != -EAGAIN); |
bc0c38d1 SR |
488 | |
489 | __update_max_tr(tr, tsk, cpu); | |
92205c23 | 490 | __raw_spin_unlock(&ftrace_max_lock); |
bc0c38d1 | 491 | } |
5d4a9dba | 492 | #endif /* CONFIG_TRACER_MAX_TRACE */ |
bc0c38d1 | 493 | |
4fcdae83 SR |
494 | /** |
495 | * register_tracer - register a tracer with the ftrace system. | |
496 | * @type - the plugin for the tracer | |
497 | * | |
498 | * Register a new plugin tracer. | |
499 | */ | |
bc0c38d1 | 500 | int register_tracer(struct tracer *type) |
e7669b8e HE |
501 | __releases(kernel_lock) |
502 | __acquires(kernel_lock) | |
bc0c38d1 SR |
503 | { |
504 | struct tracer *t; | |
505 | int len; | |
506 | int ret = 0; | |
507 | ||
508 | if (!type->name) { | |
509 | pr_info("Tracer must have a name\n"); | |
510 | return -1; | |
511 | } | |
512 | ||
86fa2f60 IM |
513 | /* |
514 | * When this gets called we hold the BKL which means that | |
515 | * preemption is disabled. Various trace selftests however | |
516 | * need to disable and enable preemption for successful tests. | |
517 | * So we drop the BKL here and grab it after the tests again. | |
518 | */ | |
519 | unlock_kernel(); | |
bc0c38d1 | 520 | mutex_lock(&trace_types_lock); |
86fa2f60 | 521 | |
8e1b82e0 FW |
522 | tracing_selftest_running = true; |
523 | ||
bc0c38d1 SR |
524 | for (t = trace_types; t; t = t->next) { |
525 | if (strcmp(type->name, t->name) == 0) { | |
526 | /* already found */ | |
527 | pr_info("Trace %s already registered\n", | |
528 | type->name); | |
529 | ret = -1; | |
530 | goto out; | |
531 | } | |
532 | } | |
533 | ||
adf9f195 FW |
534 | if (!type->set_flag) |
535 | type->set_flag = &dummy_set_flag; | |
536 | if (!type->flags) | |
537 | type->flags = &dummy_tracer_flags; | |
538 | else | |
539 | if (!type->flags->opts) | |
540 | type->flags->opts = dummy_tracer_opt; | |
6eaaa5d5 FW |
541 | if (!type->wait_pipe) |
542 | type->wait_pipe = default_wait_pipe; | |
543 | ||
adf9f195 | 544 | |
60a11774 | 545 | #ifdef CONFIG_FTRACE_STARTUP_TEST |
b2821ae6 | 546 | if (type->selftest && !tracing_selftest_disabled) { |
60a11774 | 547 | struct tracer *saved_tracer = current_trace; |
60a11774 | 548 | struct trace_array *tr = &global_trace; |
ff32504f | 549 | |
60a11774 SR |
550 | /* |
551 | * Run a selftest on this tracer. | |
552 | * Here we reset the trace buffer, and set the current | |
553 | * tracer to be this tracer. The tracer can then run some | |
554 | * internal tracing to verify that everything is in order. | |
555 | * If we fail, we do not register this tracer. | |
556 | */ | |
76f0d073 | 557 | tracing_reset_online_cpus(tr); |
86fa2f60 | 558 | |
60a11774 | 559 | current_trace = type; |
60a11774 SR |
560 | /* the test is responsible for initializing and enabling */ |
561 | pr_info("Testing tracer %s: ", type->name); | |
562 | ret = type->selftest(type, tr); | |
563 | /* the test is responsible for resetting too */ | |
564 | current_trace = saved_tracer; | |
60a11774 SR |
565 | if (ret) { |
566 | printk(KERN_CONT "FAILED!\n"); | |
567 | goto out; | |
568 | } | |
1d4db00a | 569 | /* Only reset on passing, to avoid touching corrupted buffers */ |
76f0d073 | 570 | tracing_reset_online_cpus(tr); |
86fa2f60 | 571 | |
60a11774 SR |
572 | printk(KERN_CONT "PASSED\n"); |
573 | } | |
574 | #endif | |
575 | ||
bc0c38d1 SR |
576 | type->next = trace_types; |
577 | trace_types = type; | |
578 | len = strlen(type->name); | |
579 | if (len > max_tracer_type_len) | |
580 | max_tracer_type_len = len; | |
60a11774 | 581 | |
bc0c38d1 | 582 | out: |
8e1b82e0 | 583 | tracing_selftest_running = false; |
bc0c38d1 SR |
584 | mutex_unlock(&trace_types_lock); |
585 | ||
dac74940 SR |
586 | if (ret || !default_bootup_tracer) |
587 | goto out_unlock; | |
588 | ||
589 | if (strncmp(default_bootup_tracer, type->name, BOOTUP_TRACER_SIZE)) | |
590 | goto out_unlock; | |
591 | ||
592 | printk(KERN_INFO "Starting tracer '%s'\n", type->name); | |
593 | /* Do we want this tracer to start on bootup? */ | |
594 | tracing_set_tracer(type->name); | |
595 | default_bootup_tracer = NULL; | |
596 | /* disable other selftests, since this will break it. */ | |
597 | tracing_selftest_disabled = 1; | |
b2821ae6 | 598 | #ifdef CONFIG_FTRACE_STARTUP_TEST |
dac74940 SR |
599 | printk(KERN_INFO "Disabling FTRACE selftests due to running tracer '%s'\n", |
600 | type->name); | |
b2821ae6 | 601 | #endif |
b2821ae6 | 602 | |
dac74940 | 603 | out_unlock: |
b2821ae6 | 604 | lock_kernel(); |
bc0c38d1 SR |
605 | return ret; |
606 | } | |
607 | ||
608 | void unregister_tracer(struct tracer *type) | |
609 | { | |
610 | struct tracer **t; | |
611 | int len; | |
612 | ||
613 | mutex_lock(&trace_types_lock); | |
614 | for (t = &trace_types; *t; t = &(*t)->next) { | |
615 | if (*t == type) | |
616 | goto found; | |
617 | } | |
618 | pr_info("Trace %s not registered\n", type->name); | |
619 | goto out; | |
620 | ||
621 | found: | |
622 | *t = (*t)->next; | |
b5db03c4 ACM |
623 | |
624 | if (type == current_trace && tracer_enabled) { | |
625 | tracer_enabled = 0; | |
626 | tracing_stop(); | |
627 | if (current_trace->stop) | |
628 | current_trace->stop(&global_trace); | |
629 | current_trace = &nop_trace; | |
630 | } | |
631 | ||
bc0c38d1 SR |
632 | if (strlen(type->name) != max_tracer_type_len) |
633 | goto out; | |
634 | ||
635 | max_tracer_type_len = 0; | |
636 | for (t = &trace_types; *t; t = &(*t)->next) { | |
637 | len = strlen((*t)->name); | |
638 | if (len > max_tracer_type_len) | |
639 | max_tracer_type_len = len; | |
640 | } | |
641 | out: | |
642 | mutex_unlock(&trace_types_lock); | |
643 | } | |
644 | ||
f633903a | 645 | static void __tracing_reset(struct trace_array *tr, int cpu) |
bc0c38d1 | 646 | { |
d769041f | 647 | ftrace_disable_cpu(); |
3928a8a2 | 648 | ring_buffer_reset_cpu(tr->buffer, cpu); |
d769041f | 649 | ftrace_enable_cpu(); |
bc0c38d1 SR |
650 | } |
651 | ||
f633903a SR |
652 | void tracing_reset(struct trace_array *tr, int cpu) |
653 | { | |
654 | struct ring_buffer *buffer = tr->buffer; | |
655 | ||
656 | ring_buffer_record_disable(buffer); | |
657 | ||
658 | /* Make sure all commits have finished */ | |
659 | synchronize_sched(); | |
660 | __tracing_reset(tr, cpu); | |
661 | ||
662 | ring_buffer_record_enable(buffer); | |
663 | } | |
664 | ||
213cc060 PE |
665 | void tracing_reset_online_cpus(struct trace_array *tr) |
666 | { | |
621968cd | 667 | struct ring_buffer *buffer = tr->buffer; |
213cc060 PE |
668 | int cpu; |
669 | ||
621968cd SR |
670 | ring_buffer_record_disable(buffer); |
671 | ||
672 | /* Make sure all commits have finished */ | |
673 | synchronize_sched(); | |
674 | ||
213cc060 PE |
675 | tr->time_start = ftrace_now(tr->cpu); |
676 | ||
677 | for_each_online_cpu(cpu) | |
f633903a | 678 | __tracing_reset(tr, cpu); |
621968cd SR |
679 | |
680 | ring_buffer_record_enable(buffer); | |
213cc060 PE |
681 | } |
682 | ||
9456f0fa SR |
683 | void tracing_reset_current(int cpu) |
684 | { | |
685 | tracing_reset(&global_trace, cpu); | |
686 | } | |
687 | ||
688 | void tracing_reset_current_online_cpus(void) | |
689 | { | |
690 | tracing_reset_online_cpus(&global_trace); | |
691 | } | |
692 | ||
bc0c38d1 | 693 | #define SAVED_CMDLINES 128 |
2c7eea4c | 694 | #define NO_CMDLINE_MAP UINT_MAX |
bc0c38d1 SR |
695 | static unsigned map_pid_to_cmdline[PID_MAX_DEFAULT+1]; |
696 | static unsigned map_cmdline_to_pid[SAVED_CMDLINES]; | |
697 | static char saved_cmdlines[SAVED_CMDLINES][TASK_COMM_LEN]; | |
698 | static int cmdline_idx; | |
efed792d | 699 | static raw_spinlock_t trace_cmdline_lock = __RAW_SPIN_LOCK_UNLOCKED; |
25b0b44a | 700 | |
25b0b44a | 701 | /* temporary disable recording */ |
4fd27358 | 702 | static atomic_t trace_record_cmdline_disabled __read_mostly; |
bc0c38d1 SR |
703 | |
704 | static void trace_init_cmdlines(void) | |
705 | { | |
2c7eea4c TG |
706 | memset(&map_pid_to_cmdline, NO_CMDLINE_MAP, sizeof(map_pid_to_cmdline)); |
707 | memset(&map_cmdline_to_pid, NO_CMDLINE_MAP, sizeof(map_cmdline_to_pid)); | |
bc0c38d1 SR |
708 | cmdline_idx = 0; |
709 | } | |
710 | ||
69bb54ec SR |
711 | /** |
712 | * ftrace_off_permanent - disable all ftrace code permanently | |
713 | * | |
714 | * This should only be called when a serious anomally has | |
715 | * been detected. This will turn off the function tracing, | |
716 | * ring buffers, and other tracing utilites. It takes no | |
717 | * locks and can be called from any context. | |
718 | */ | |
719 | void ftrace_off_permanent(void) | |
720 | { | |
721 | tracing_disabled = 1; | |
722 | ftrace_stop(); | |
723 | tracing_off_permanent(); | |
724 | } | |
725 | ||
0f048701 SR |
726 | /** |
727 | * tracing_start - quick start of the tracer | |
728 | * | |
729 | * If tracing is enabled but was stopped by tracing_stop, | |
730 | * this will start the tracer back up. | |
731 | */ | |
732 | void tracing_start(void) | |
733 | { | |
734 | struct ring_buffer *buffer; | |
735 | unsigned long flags; | |
736 | ||
737 | if (tracing_disabled) | |
738 | return; | |
739 | ||
740 | spin_lock_irqsave(&tracing_start_lock, flags); | |
b06a8301 SR |
741 | if (--trace_stop_count) { |
742 | if (trace_stop_count < 0) { | |
743 | /* Someone screwed up their debugging */ | |
744 | WARN_ON_ONCE(1); | |
745 | trace_stop_count = 0; | |
746 | } | |
0f048701 SR |
747 | goto out; |
748 | } | |
749 | ||
750 | ||
751 | buffer = global_trace.buffer; | |
752 | if (buffer) | |
753 | ring_buffer_record_enable(buffer); | |
754 | ||
755 | buffer = max_tr.buffer; | |
756 | if (buffer) | |
757 | ring_buffer_record_enable(buffer); | |
758 | ||
759 | ftrace_start(); | |
760 | out: | |
761 | spin_unlock_irqrestore(&tracing_start_lock, flags); | |
762 | } | |
763 | ||
764 | /** | |
765 | * tracing_stop - quick stop of the tracer | |
766 | * | |
767 | * Light weight way to stop tracing. Use in conjunction with | |
768 | * tracing_start. | |
769 | */ | |
770 | void tracing_stop(void) | |
771 | { | |
772 | struct ring_buffer *buffer; | |
773 | unsigned long flags; | |
774 | ||
775 | ftrace_stop(); | |
776 | spin_lock_irqsave(&tracing_start_lock, flags); | |
777 | if (trace_stop_count++) | |
778 | goto out; | |
779 | ||
780 | buffer = global_trace.buffer; | |
781 | if (buffer) | |
782 | ring_buffer_record_disable(buffer); | |
783 | ||
784 | buffer = max_tr.buffer; | |
785 | if (buffer) | |
786 | ring_buffer_record_disable(buffer); | |
787 | ||
788 | out: | |
789 | spin_unlock_irqrestore(&tracing_start_lock, flags); | |
790 | } | |
791 | ||
e309b41d | 792 | void trace_stop_cmdline_recording(void); |
bc0c38d1 | 793 | |
e309b41d | 794 | static void trace_save_cmdline(struct task_struct *tsk) |
bc0c38d1 | 795 | { |
a635cf04 | 796 | unsigned pid, idx; |
bc0c38d1 SR |
797 | |
798 | if (!tsk->pid || unlikely(tsk->pid > PID_MAX_DEFAULT)) | |
799 | return; | |
800 | ||
801 | /* | |
802 | * It's not the end of the world if we don't get | |
803 | * the lock, but we also don't want to spin | |
804 | * nor do we want to disable interrupts, | |
805 | * so if we miss here, then better luck next time. | |
806 | */ | |
efed792d | 807 | if (!__raw_spin_trylock(&trace_cmdline_lock)) |
bc0c38d1 SR |
808 | return; |
809 | ||
810 | idx = map_pid_to_cmdline[tsk->pid]; | |
2c7eea4c | 811 | if (idx == NO_CMDLINE_MAP) { |
bc0c38d1 SR |
812 | idx = (cmdline_idx + 1) % SAVED_CMDLINES; |
813 | ||
a635cf04 CE |
814 | /* |
815 | * Check whether the cmdline buffer at idx has a pid | |
816 | * mapped. We are going to overwrite that entry so we | |
817 | * need to clear the map_pid_to_cmdline. Otherwise we | |
818 | * would read the new comm for the old pid. | |
819 | */ | |
820 | pid = map_cmdline_to_pid[idx]; | |
821 | if (pid != NO_CMDLINE_MAP) | |
822 | map_pid_to_cmdline[pid] = NO_CMDLINE_MAP; | |
bc0c38d1 | 823 | |
a635cf04 | 824 | map_cmdline_to_pid[idx] = tsk->pid; |
bc0c38d1 SR |
825 | map_pid_to_cmdline[tsk->pid] = idx; |
826 | ||
827 | cmdline_idx = idx; | |
828 | } | |
829 | ||
830 | memcpy(&saved_cmdlines[idx], tsk->comm, TASK_COMM_LEN); | |
831 | ||
efed792d | 832 | __raw_spin_unlock(&trace_cmdline_lock); |
bc0c38d1 SR |
833 | } |
834 | ||
4ca53085 | 835 | void trace_find_cmdline(int pid, char comm[]) |
bc0c38d1 | 836 | { |
bc0c38d1 SR |
837 | unsigned map; |
838 | ||
4ca53085 SR |
839 | if (!pid) { |
840 | strcpy(comm, "<idle>"); | |
841 | return; | |
842 | } | |
bc0c38d1 | 843 | |
4ca53085 SR |
844 | if (pid > PID_MAX_DEFAULT) { |
845 | strcpy(comm, "<...>"); | |
846 | return; | |
847 | } | |
bc0c38d1 | 848 | |
5b6045a9 | 849 | preempt_disable(); |
4ca53085 | 850 | __raw_spin_lock(&trace_cmdline_lock); |
bc0c38d1 | 851 | map = map_pid_to_cmdline[pid]; |
50d88758 TG |
852 | if (map != NO_CMDLINE_MAP) |
853 | strcpy(comm, saved_cmdlines[map]); | |
854 | else | |
855 | strcpy(comm, "<...>"); | |
bc0c38d1 | 856 | |
4ca53085 | 857 | __raw_spin_unlock(&trace_cmdline_lock); |
5b6045a9 | 858 | preempt_enable(); |
bc0c38d1 SR |
859 | } |
860 | ||
e309b41d | 861 | void tracing_record_cmdline(struct task_struct *tsk) |
bc0c38d1 | 862 | { |
18aecd36 TG |
863 | if (atomic_read(&trace_record_cmdline_disabled) || !tracer_enabled || |
864 | !tracing_is_on()) | |
bc0c38d1 SR |
865 | return; |
866 | ||
867 | trace_save_cmdline(tsk); | |
868 | } | |
869 | ||
45dcd8b8 | 870 | void |
38697053 SR |
871 | tracing_generic_entry_update(struct trace_entry *entry, unsigned long flags, |
872 | int pc) | |
bc0c38d1 SR |
873 | { |
874 | struct task_struct *tsk = current; | |
bc0c38d1 | 875 | |
777e208d SR |
876 | entry->preempt_count = pc & 0xff; |
877 | entry->pid = (tsk) ? tsk->pid : 0; | |
ef18012b | 878 | entry->tgid = (tsk) ? tsk->tgid : 0; |
777e208d | 879 | entry->flags = |
9244489a | 880 | #ifdef CONFIG_TRACE_IRQFLAGS_SUPPORT |
2e2ca155 | 881 | (irqs_disabled_flags(flags) ? TRACE_FLAG_IRQS_OFF : 0) | |
9244489a SR |
882 | #else |
883 | TRACE_FLAG_IRQS_NOSUPPORT | | |
884 | #endif | |
bc0c38d1 SR |
885 | ((pc & HARDIRQ_MASK) ? TRACE_FLAG_HARDIRQ : 0) | |
886 | ((pc & SOFTIRQ_MASK) ? TRACE_FLAG_SOFTIRQ : 0) | | |
887 | (need_resched() ? TRACE_FLAG_NEED_RESCHED : 0); | |
888 | } | |
f413cdb8 | 889 | EXPORT_SYMBOL_GPL(tracing_generic_entry_update); |
bc0c38d1 | 890 | |
e77405ad SR |
891 | struct ring_buffer_event * |
892 | trace_buffer_lock_reserve(struct ring_buffer *buffer, | |
893 | int type, | |
894 | unsigned long len, | |
895 | unsigned long flags, int pc) | |
51a763dd ACM |
896 | { |
897 | struct ring_buffer_event *event; | |
898 | ||
e77405ad | 899 | event = ring_buffer_lock_reserve(buffer, len); |
51a763dd ACM |
900 | if (event != NULL) { |
901 | struct trace_entry *ent = ring_buffer_event_data(event); | |
902 | ||
903 | tracing_generic_entry_update(ent, flags, pc); | |
904 | ent->type = type; | |
905 | } | |
906 | ||
907 | return event; | |
908 | } | |
51a763dd | 909 | |
e77405ad SR |
910 | static inline void |
911 | __trace_buffer_unlock_commit(struct ring_buffer *buffer, | |
912 | struct ring_buffer_event *event, | |
913 | unsigned long flags, int pc, | |
914 | int wake) | |
51a763dd | 915 | { |
e77405ad | 916 | ring_buffer_unlock_commit(buffer, event); |
51a763dd | 917 | |
e77405ad SR |
918 | ftrace_trace_stack(buffer, flags, 6, pc); |
919 | ftrace_trace_userstack(buffer, flags, pc); | |
07edf712 FW |
920 | |
921 | if (wake) | |
922 | trace_wake_up(); | |
923 | } | |
924 | ||
e77405ad SR |
925 | void trace_buffer_unlock_commit(struct ring_buffer *buffer, |
926 | struct ring_buffer_event *event, | |
927 | unsigned long flags, int pc) | |
07edf712 | 928 | { |
e77405ad | 929 | __trace_buffer_unlock_commit(buffer, event, flags, pc, 1); |
51a763dd ACM |
930 | } |
931 | ||
ef5580d0 | 932 | struct ring_buffer_event * |
e77405ad SR |
933 | trace_current_buffer_lock_reserve(struct ring_buffer **current_rb, |
934 | int type, unsigned long len, | |
ef5580d0 SR |
935 | unsigned long flags, int pc) |
936 | { | |
e77405ad SR |
937 | *current_rb = global_trace.buffer; |
938 | return trace_buffer_lock_reserve(*current_rb, | |
ef5580d0 SR |
939 | type, len, flags, pc); |
940 | } | |
94487d6d | 941 | EXPORT_SYMBOL_GPL(trace_current_buffer_lock_reserve); |
ef5580d0 | 942 | |
e77405ad SR |
943 | void trace_current_buffer_unlock_commit(struct ring_buffer *buffer, |
944 | struct ring_buffer_event *event, | |
ef5580d0 SR |
945 | unsigned long flags, int pc) |
946 | { | |
e77405ad | 947 | __trace_buffer_unlock_commit(buffer, event, flags, pc, 1); |
07edf712 | 948 | } |
94487d6d | 949 | EXPORT_SYMBOL_GPL(trace_current_buffer_unlock_commit); |
07edf712 | 950 | |
e77405ad SR |
951 | void trace_nowake_buffer_unlock_commit(struct ring_buffer *buffer, |
952 | struct ring_buffer_event *event, | |
953 | unsigned long flags, int pc) | |
07edf712 | 954 | { |
e77405ad | 955 | __trace_buffer_unlock_commit(buffer, event, flags, pc, 0); |
77d9f465 | 956 | } |
94487d6d | 957 | EXPORT_SYMBOL_GPL(trace_nowake_buffer_unlock_commit); |
77d9f465 | 958 | |
e77405ad SR |
959 | void trace_current_buffer_discard_commit(struct ring_buffer *buffer, |
960 | struct ring_buffer_event *event) | |
77d9f465 | 961 | { |
e77405ad | 962 | ring_buffer_discard_commit(buffer, event); |
ef5580d0 | 963 | } |
12acd473 | 964 | EXPORT_SYMBOL_GPL(trace_current_buffer_discard_commit); |
ef5580d0 | 965 | |
e309b41d | 966 | void |
7be42151 | 967 | trace_function(struct trace_array *tr, |
38697053 SR |
968 | unsigned long ip, unsigned long parent_ip, unsigned long flags, |
969 | int pc) | |
bc0c38d1 | 970 | { |
e1112b4d | 971 | struct ftrace_event_call *call = &event_function; |
e77405ad | 972 | struct ring_buffer *buffer = tr->buffer; |
3928a8a2 | 973 | struct ring_buffer_event *event; |
777e208d | 974 | struct ftrace_entry *entry; |
bc0c38d1 | 975 | |
d769041f SR |
976 | /* If we are reading the ring buffer, don't trace */ |
977 | if (unlikely(local_read(&__get_cpu_var(ftrace_cpu_disabled)))) | |
978 | return; | |
979 | ||
e77405ad | 980 | event = trace_buffer_lock_reserve(buffer, TRACE_FN, sizeof(*entry), |
51a763dd | 981 | flags, pc); |
3928a8a2 SR |
982 | if (!event) |
983 | return; | |
984 | entry = ring_buffer_event_data(event); | |
777e208d SR |
985 | entry->ip = ip; |
986 | entry->parent_ip = parent_ip; | |
e1112b4d | 987 | |
e77405ad SR |
988 | if (!filter_check_discard(call, entry, buffer, event)) |
989 | ring_buffer_unlock_commit(buffer, event); | |
bc0c38d1 SR |
990 | } |
991 | ||
e309b41d | 992 | void |
2e0f5761 | 993 | ftrace(struct trace_array *tr, struct trace_array_cpu *data, |
38697053 SR |
994 | unsigned long ip, unsigned long parent_ip, unsigned long flags, |
995 | int pc) | |
2e0f5761 IM |
996 | { |
997 | if (likely(!atomic_read(&data->disabled))) | |
7be42151 | 998 | trace_function(tr, ip, parent_ip, flags, pc); |
2e0f5761 IM |
999 | } |
1000 | ||
c0a0d0d3 | 1001 | #ifdef CONFIG_STACKTRACE |
e77405ad | 1002 | static void __ftrace_trace_stack(struct ring_buffer *buffer, |
53614991 SR |
1003 | unsigned long flags, |
1004 | int skip, int pc) | |
86387f7e | 1005 | { |
e1112b4d | 1006 | struct ftrace_event_call *call = &event_kernel_stack; |
3928a8a2 | 1007 | struct ring_buffer_event *event; |
777e208d | 1008 | struct stack_entry *entry; |
86387f7e IM |
1009 | struct stack_trace trace; |
1010 | ||
e77405ad | 1011 | event = trace_buffer_lock_reserve(buffer, TRACE_STACK, |
51a763dd | 1012 | sizeof(*entry), flags, pc); |
3928a8a2 SR |
1013 | if (!event) |
1014 | return; | |
1015 | entry = ring_buffer_event_data(event); | |
777e208d | 1016 | memset(&entry->caller, 0, sizeof(entry->caller)); |
86387f7e IM |
1017 | |
1018 | trace.nr_entries = 0; | |
1019 | trace.max_entries = FTRACE_STACK_ENTRIES; | |
1020 | trace.skip = skip; | |
777e208d | 1021 | trace.entries = entry->caller; |
86387f7e IM |
1022 | |
1023 | save_stack_trace(&trace); | |
e77405ad SR |
1024 | if (!filter_check_discard(call, entry, buffer, event)) |
1025 | ring_buffer_unlock_commit(buffer, event); | |
f0a920d5 IM |
1026 | } |
1027 | ||
e77405ad SR |
1028 | void ftrace_trace_stack(struct ring_buffer *buffer, unsigned long flags, |
1029 | int skip, int pc) | |
53614991 SR |
1030 | { |
1031 | if (!(trace_flags & TRACE_ITER_STACKTRACE)) | |
1032 | return; | |
1033 | ||
e77405ad | 1034 | __ftrace_trace_stack(buffer, flags, skip, pc); |
53614991 SR |
1035 | } |
1036 | ||
c0a0d0d3 FW |
1037 | void __trace_stack(struct trace_array *tr, unsigned long flags, int skip, |
1038 | int pc) | |
38697053 | 1039 | { |
e77405ad | 1040 | __ftrace_trace_stack(tr->buffer, flags, skip, pc); |
38697053 SR |
1041 | } |
1042 | ||
e77405ad SR |
1043 | void |
1044 | ftrace_trace_userstack(struct ring_buffer *buffer, unsigned long flags, int pc) | |
02b67518 | 1045 | { |
e1112b4d | 1046 | struct ftrace_event_call *call = &event_user_stack; |
8d7c6a96 | 1047 | struct ring_buffer_event *event; |
02b67518 TE |
1048 | struct userstack_entry *entry; |
1049 | struct stack_trace trace; | |
02b67518 TE |
1050 | |
1051 | if (!(trace_flags & TRACE_ITER_USERSTACKTRACE)) | |
1052 | return; | |
1053 | ||
e77405ad | 1054 | event = trace_buffer_lock_reserve(buffer, TRACE_USER_STACK, |
51a763dd | 1055 | sizeof(*entry), flags, pc); |
02b67518 TE |
1056 | if (!event) |
1057 | return; | |
1058 | entry = ring_buffer_event_data(event); | |
02b67518 TE |
1059 | |
1060 | memset(&entry->caller, 0, sizeof(entry->caller)); | |
1061 | ||
1062 | trace.nr_entries = 0; | |
1063 | trace.max_entries = FTRACE_STACK_ENTRIES; | |
1064 | trace.skip = 0; | |
1065 | trace.entries = entry->caller; | |
1066 | ||
1067 | save_stack_trace_user(&trace); | |
e77405ad SR |
1068 | if (!filter_check_discard(call, entry, buffer, event)) |
1069 | ring_buffer_unlock_commit(buffer, event); | |
02b67518 TE |
1070 | } |
1071 | ||
4fd27358 HE |
1072 | #ifdef UNUSED |
1073 | static void __trace_userstack(struct trace_array *tr, unsigned long flags) | |
02b67518 | 1074 | { |
7be42151 | 1075 | ftrace_trace_userstack(tr, flags, preempt_count()); |
02b67518 | 1076 | } |
4fd27358 | 1077 | #endif /* UNUSED */ |
02b67518 | 1078 | |
c0a0d0d3 FW |
1079 | #endif /* CONFIG_STACKTRACE */ |
1080 | ||
38697053 | 1081 | static void |
7be42151 | 1082 | ftrace_trace_special(void *__tr, |
38697053 SR |
1083 | unsigned long arg1, unsigned long arg2, unsigned long arg3, |
1084 | int pc) | |
a4feb834 | 1085 | { |
3928a8a2 | 1086 | struct ring_buffer_event *event; |
a4feb834 | 1087 | struct trace_array *tr = __tr; |
e77405ad | 1088 | struct ring_buffer *buffer = tr->buffer; |
777e208d | 1089 | struct special_entry *entry; |
a4feb834 | 1090 | |
e77405ad | 1091 | event = trace_buffer_lock_reserve(buffer, TRACE_SPECIAL, |
51a763dd | 1092 | sizeof(*entry), 0, pc); |
3928a8a2 SR |
1093 | if (!event) |
1094 | return; | |
1095 | entry = ring_buffer_event_data(event); | |
777e208d SR |
1096 | entry->arg1 = arg1; |
1097 | entry->arg2 = arg2; | |
1098 | entry->arg3 = arg3; | |
e77405ad | 1099 | trace_buffer_unlock_commit(buffer, event, 0, pc); |
a4feb834 IM |
1100 | } |
1101 | ||
38697053 SR |
1102 | void |
1103 | __trace_special(void *__tr, void *__data, | |
1104 | unsigned long arg1, unsigned long arg2, unsigned long arg3) | |
1105 | { | |
7be42151 | 1106 | ftrace_trace_special(__tr, arg1, arg2, arg3, preempt_count()); |
38697053 SR |
1107 | } |
1108 | ||
4902f884 SR |
1109 | void |
1110 | ftrace_special(unsigned long arg1, unsigned long arg2, unsigned long arg3) | |
1111 | { | |
1112 | struct trace_array *tr = &global_trace; | |
1113 | struct trace_array_cpu *data; | |
5aa1ba6a | 1114 | unsigned long flags; |
4902f884 | 1115 | int cpu; |
38697053 | 1116 | int pc; |
4902f884 | 1117 | |
c76f0694 | 1118 | if (tracing_disabled) |
4902f884 SR |
1119 | return; |
1120 | ||
38697053 | 1121 | pc = preempt_count(); |
5aa1ba6a | 1122 | local_irq_save(flags); |
4902f884 SR |
1123 | cpu = raw_smp_processor_id(); |
1124 | data = tr->data[cpu]; | |
4902f884 | 1125 | |
5aa1ba6a | 1126 | if (likely(atomic_inc_return(&data->disabled) == 1)) |
7be42151 | 1127 | ftrace_trace_special(tr, arg1, arg2, arg3, pc); |
4902f884 | 1128 | |
5aa1ba6a SR |
1129 | atomic_dec(&data->disabled); |
1130 | local_irq_restore(flags); | |
4902f884 SR |
1131 | } |
1132 | ||
769b0441 | 1133 | /** |
48ead020 | 1134 | * trace_vbprintk - write binary msg to tracing buffer |
769b0441 FW |
1135 | * |
1136 | */ | |
40ce74f1 | 1137 | int trace_vbprintk(unsigned long ip, const char *fmt, va_list args) |
769b0441 | 1138 | { |
80370cb7 SR |
1139 | static raw_spinlock_t trace_buf_lock = |
1140 | (raw_spinlock_t)__RAW_SPIN_LOCK_UNLOCKED; | |
769b0441 FW |
1141 | static u32 trace_buf[TRACE_BUF_SIZE]; |
1142 | ||
e1112b4d | 1143 | struct ftrace_event_call *call = &event_bprint; |
769b0441 | 1144 | struct ring_buffer_event *event; |
e77405ad | 1145 | struct ring_buffer *buffer; |
769b0441 FW |
1146 | struct trace_array *tr = &global_trace; |
1147 | struct trace_array_cpu *data; | |
48ead020 | 1148 | struct bprint_entry *entry; |
769b0441 | 1149 | unsigned long flags; |
3189cdb3 | 1150 | int disable; |
769b0441 FW |
1151 | int resched; |
1152 | int cpu, len = 0, size, pc; | |
1153 | ||
1154 | if (unlikely(tracing_selftest_running || tracing_disabled)) | |
1155 | return 0; | |
1156 | ||
1157 | /* Don't pollute graph traces with trace_vprintk internals */ | |
1158 | pause_graph_tracing(); | |
1159 | ||
1160 | pc = preempt_count(); | |
1161 | resched = ftrace_preempt_disable(); | |
1162 | cpu = raw_smp_processor_id(); | |
1163 | data = tr->data[cpu]; | |
1164 | ||
3189cdb3 SR |
1165 | disable = atomic_inc_return(&data->disabled); |
1166 | if (unlikely(disable != 1)) | |
769b0441 FW |
1167 | goto out; |
1168 | ||
80370cb7 SR |
1169 | /* Lockdep uses trace_printk for lock tracing */ |
1170 | local_irq_save(flags); | |
1171 | __raw_spin_lock(&trace_buf_lock); | |
769b0441 FW |
1172 | len = vbin_printf(trace_buf, TRACE_BUF_SIZE, fmt, args); |
1173 | ||
1174 | if (len > TRACE_BUF_SIZE || len < 0) | |
1175 | goto out_unlock; | |
1176 | ||
1177 | size = sizeof(*entry) + sizeof(u32) * len; | |
e77405ad SR |
1178 | buffer = tr->buffer; |
1179 | event = trace_buffer_lock_reserve(buffer, TRACE_BPRINT, size, | |
1180 | flags, pc); | |
769b0441 FW |
1181 | if (!event) |
1182 | goto out_unlock; | |
1183 | entry = ring_buffer_event_data(event); | |
1184 | entry->ip = ip; | |
769b0441 FW |
1185 | entry->fmt = fmt; |
1186 | ||
1187 | memcpy(entry->buf, trace_buf, sizeof(u32) * len); | |
e77405ad SR |
1188 | if (!filter_check_discard(call, entry, buffer, event)) |
1189 | ring_buffer_unlock_commit(buffer, event); | |
769b0441 FW |
1190 | |
1191 | out_unlock: | |
80370cb7 SR |
1192 | __raw_spin_unlock(&trace_buf_lock); |
1193 | local_irq_restore(flags); | |
769b0441 FW |
1194 | |
1195 | out: | |
3189cdb3 | 1196 | atomic_dec_return(&data->disabled); |
769b0441 FW |
1197 | ftrace_preempt_enable(resched); |
1198 | unpause_graph_tracing(); | |
1199 | ||
1200 | return len; | |
1201 | } | |
48ead020 FW |
1202 | EXPORT_SYMBOL_GPL(trace_vbprintk); |
1203 | ||
659372d3 SR |
1204 | int trace_array_printk(struct trace_array *tr, |
1205 | unsigned long ip, const char *fmt, ...) | |
1206 | { | |
1207 | int ret; | |
1208 | va_list ap; | |
1209 | ||
1210 | if (!(trace_flags & TRACE_ITER_PRINTK)) | |
1211 | return 0; | |
1212 | ||
1213 | va_start(ap, fmt); | |
1214 | ret = trace_array_vprintk(tr, ip, fmt, ap); | |
1215 | va_end(ap); | |
1216 | return ret; | |
1217 | } | |
1218 | ||
1219 | int trace_array_vprintk(struct trace_array *tr, | |
1220 | unsigned long ip, const char *fmt, va_list args) | |
48ead020 FW |
1221 | { |
1222 | static raw_spinlock_t trace_buf_lock = __RAW_SPIN_LOCK_UNLOCKED; | |
1223 | static char trace_buf[TRACE_BUF_SIZE]; | |
1224 | ||
e1112b4d | 1225 | struct ftrace_event_call *call = &event_print; |
48ead020 | 1226 | struct ring_buffer_event *event; |
e77405ad | 1227 | struct ring_buffer *buffer; |
48ead020 FW |
1228 | struct trace_array_cpu *data; |
1229 | int cpu, len = 0, size, pc; | |
1230 | struct print_entry *entry; | |
1231 | unsigned long irq_flags; | |
3189cdb3 | 1232 | int disable; |
48ead020 FW |
1233 | |
1234 | if (tracing_disabled || tracing_selftest_running) | |
1235 | return 0; | |
1236 | ||
1237 | pc = preempt_count(); | |
1238 | preempt_disable_notrace(); | |
1239 | cpu = raw_smp_processor_id(); | |
1240 | data = tr->data[cpu]; | |
1241 | ||
3189cdb3 SR |
1242 | disable = atomic_inc_return(&data->disabled); |
1243 | if (unlikely(disable != 1)) | |
48ead020 FW |
1244 | goto out; |
1245 | ||
1246 | pause_graph_tracing(); | |
1247 | raw_local_irq_save(irq_flags); | |
1248 | __raw_spin_lock(&trace_buf_lock); | |
1249 | len = vsnprintf(trace_buf, TRACE_BUF_SIZE, fmt, args); | |
1250 | ||
1251 | len = min(len, TRACE_BUF_SIZE-1); | |
1252 | trace_buf[len] = 0; | |
1253 | ||
1254 | size = sizeof(*entry) + len + 1; | |
e77405ad SR |
1255 | buffer = tr->buffer; |
1256 | event = trace_buffer_lock_reserve(buffer, TRACE_PRINT, size, | |
1257 | irq_flags, pc); | |
48ead020 FW |
1258 | if (!event) |
1259 | goto out_unlock; | |
1260 | entry = ring_buffer_event_data(event); | |
1261 | entry->ip = ip; | |
48ead020 FW |
1262 | |
1263 | memcpy(&entry->buf, trace_buf, len); | |
1264 | entry->buf[len] = 0; | |
e77405ad SR |
1265 | if (!filter_check_discard(call, entry, buffer, event)) |
1266 | ring_buffer_unlock_commit(buffer, event); | |
48ead020 FW |
1267 | |
1268 | out_unlock: | |
1269 | __raw_spin_unlock(&trace_buf_lock); | |
1270 | raw_local_irq_restore(irq_flags); | |
1271 | unpause_graph_tracing(); | |
1272 | out: | |
3189cdb3 | 1273 | atomic_dec_return(&data->disabled); |
48ead020 FW |
1274 | preempt_enable_notrace(); |
1275 | ||
1276 | return len; | |
1277 | } | |
659372d3 SR |
1278 | |
1279 | int trace_vprintk(unsigned long ip, const char *fmt, va_list args) | |
1280 | { | |
1281 | return trace_array_printk(&global_trace, ip, fmt, args); | |
1282 | } | |
769b0441 FW |
1283 | EXPORT_SYMBOL_GPL(trace_vprintk); |
1284 | ||
bc0c38d1 SR |
1285 | enum trace_file_type { |
1286 | TRACE_FILE_LAT_FMT = 1, | |
12ef7d44 | 1287 | TRACE_FILE_ANNOTATE = 2, |
bc0c38d1 SR |
1288 | }; |
1289 | ||
e2ac8ef5 | 1290 | static void trace_iterator_increment(struct trace_iterator *iter) |
5a90f577 | 1291 | { |
d769041f SR |
1292 | /* Don't allow ftrace to trace into the ring buffers */ |
1293 | ftrace_disable_cpu(); | |
1294 | ||
5a90f577 | 1295 | iter->idx++; |
d769041f SR |
1296 | if (iter->buffer_iter[iter->cpu]) |
1297 | ring_buffer_read(iter->buffer_iter[iter->cpu], NULL); | |
1298 | ||
1299 | ftrace_enable_cpu(); | |
5a90f577 SR |
1300 | } |
1301 | ||
e309b41d | 1302 | static struct trace_entry * |
3928a8a2 | 1303 | peek_next_entry(struct trace_iterator *iter, int cpu, u64 *ts) |
dd0e545f | 1304 | { |
3928a8a2 SR |
1305 | struct ring_buffer_event *event; |
1306 | struct ring_buffer_iter *buf_iter = iter->buffer_iter[cpu]; | |
dd0e545f | 1307 | |
d769041f SR |
1308 | /* Don't allow ftrace to trace into the ring buffers */ |
1309 | ftrace_disable_cpu(); | |
1310 | ||
1311 | if (buf_iter) | |
1312 | event = ring_buffer_iter_peek(buf_iter, ts); | |
1313 | else | |
1314 | event = ring_buffer_peek(iter->tr->buffer, cpu, ts); | |
1315 | ||
1316 | ftrace_enable_cpu(); | |
1317 | ||
3928a8a2 | 1318 | return event ? ring_buffer_event_data(event) : NULL; |
dd0e545f | 1319 | } |
d769041f | 1320 | |
dd0e545f | 1321 | static struct trace_entry * |
3928a8a2 | 1322 | __find_next_entry(struct trace_iterator *iter, int *ent_cpu, u64 *ent_ts) |
bc0c38d1 | 1323 | { |
3928a8a2 | 1324 | struct ring_buffer *buffer = iter->tr->buffer; |
bc0c38d1 | 1325 | struct trace_entry *ent, *next = NULL; |
b04cc6b1 | 1326 | int cpu_file = iter->cpu_file; |
3928a8a2 | 1327 | u64 next_ts = 0, ts; |
bc0c38d1 SR |
1328 | int next_cpu = -1; |
1329 | int cpu; | |
1330 | ||
b04cc6b1 FW |
1331 | /* |
1332 | * If we are in a per_cpu trace file, don't bother by iterating over | |
1333 | * all cpu and peek directly. | |
1334 | */ | |
1335 | if (cpu_file > TRACE_PIPE_ALL_CPU) { | |
1336 | if (ring_buffer_empty_cpu(buffer, cpu_file)) | |
1337 | return NULL; | |
1338 | ent = peek_next_entry(iter, cpu_file, ent_ts); | |
1339 | if (ent_cpu) | |
1340 | *ent_cpu = cpu_file; | |
1341 | ||
1342 | return ent; | |
1343 | } | |
1344 | ||
ab46428c | 1345 | for_each_tracing_cpu(cpu) { |
dd0e545f | 1346 | |
3928a8a2 SR |
1347 | if (ring_buffer_empty_cpu(buffer, cpu)) |
1348 | continue; | |
dd0e545f | 1349 | |
3928a8a2 | 1350 | ent = peek_next_entry(iter, cpu, &ts); |
dd0e545f | 1351 | |
cdd31cd2 IM |
1352 | /* |
1353 | * Pick the entry with the smallest timestamp: | |
1354 | */ | |
3928a8a2 | 1355 | if (ent && (!next || ts < next_ts)) { |
bc0c38d1 SR |
1356 | next = ent; |
1357 | next_cpu = cpu; | |
3928a8a2 | 1358 | next_ts = ts; |
bc0c38d1 SR |
1359 | } |
1360 | } | |
1361 | ||
1362 | if (ent_cpu) | |
1363 | *ent_cpu = next_cpu; | |
1364 | ||
3928a8a2 SR |
1365 | if (ent_ts) |
1366 | *ent_ts = next_ts; | |
1367 | ||
bc0c38d1 SR |
1368 | return next; |
1369 | } | |
1370 | ||
dd0e545f | 1371 | /* Find the next real entry, without updating the iterator itself */ |
c4a8e8be FW |
1372 | struct trace_entry *trace_find_next_entry(struct trace_iterator *iter, |
1373 | int *ent_cpu, u64 *ent_ts) | |
bc0c38d1 | 1374 | { |
3928a8a2 | 1375 | return __find_next_entry(iter, ent_cpu, ent_ts); |
dd0e545f SR |
1376 | } |
1377 | ||
1378 | /* Find the next real entry, and increment the iterator to the next entry */ | |
1379 | static void *find_next_entry_inc(struct trace_iterator *iter) | |
1380 | { | |
3928a8a2 | 1381 | iter->ent = __find_next_entry(iter, &iter->cpu, &iter->ts); |
dd0e545f | 1382 | |
3928a8a2 | 1383 | if (iter->ent) |
e2ac8ef5 | 1384 | trace_iterator_increment(iter); |
dd0e545f | 1385 | |
3928a8a2 | 1386 | return iter->ent ? iter : NULL; |
b3806b43 | 1387 | } |
bc0c38d1 | 1388 | |
e309b41d | 1389 | static void trace_consume(struct trace_iterator *iter) |
b3806b43 | 1390 | { |
d769041f SR |
1391 | /* Don't allow ftrace to trace into the ring buffers */ |
1392 | ftrace_disable_cpu(); | |
3928a8a2 | 1393 | ring_buffer_consume(iter->tr->buffer, iter->cpu, &iter->ts); |
d769041f | 1394 | ftrace_enable_cpu(); |
bc0c38d1 SR |
1395 | } |
1396 | ||
e309b41d | 1397 | static void *s_next(struct seq_file *m, void *v, loff_t *pos) |
bc0c38d1 SR |
1398 | { |
1399 | struct trace_iterator *iter = m->private; | |
bc0c38d1 | 1400 | int i = (int)*pos; |
4e3c3333 | 1401 | void *ent; |
bc0c38d1 SR |
1402 | |
1403 | (*pos)++; | |
1404 | ||
1405 | /* can't go backwards */ | |
1406 | if (iter->idx > i) | |
1407 | return NULL; | |
1408 | ||
1409 | if (iter->idx < 0) | |
1410 | ent = find_next_entry_inc(iter); | |
1411 | else | |
1412 | ent = iter; | |
1413 | ||
1414 | while (ent && iter->idx < i) | |
1415 | ent = find_next_entry_inc(iter); | |
1416 | ||
1417 | iter->pos = *pos; | |
1418 | ||
bc0c38d1 SR |
1419 | return ent; |
1420 | } | |
1421 | ||
2f26ebd5 SR |
1422 | static void tracing_iter_reset(struct trace_iterator *iter, int cpu) |
1423 | { | |
1424 | struct trace_array *tr = iter->tr; | |
1425 | struct ring_buffer_event *event; | |
1426 | struct ring_buffer_iter *buf_iter; | |
1427 | unsigned long entries = 0; | |
1428 | u64 ts; | |
1429 | ||
1430 | tr->data[cpu]->skipped_entries = 0; | |
1431 | ||
1432 | if (!iter->buffer_iter[cpu]) | |
1433 | return; | |
1434 | ||
1435 | buf_iter = iter->buffer_iter[cpu]; | |
1436 | ring_buffer_iter_reset(buf_iter); | |
1437 | ||
1438 | /* | |
1439 | * We could have the case with the max latency tracers | |
1440 | * that a reset never took place on a cpu. This is evident | |
1441 | * by the timestamp being before the start of the buffer. | |
1442 | */ | |
1443 | while ((event = ring_buffer_iter_peek(buf_iter, &ts))) { | |
1444 | if (ts >= iter->tr->time_start) | |
1445 | break; | |
1446 | entries++; | |
1447 | ring_buffer_read(buf_iter, NULL); | |
1448 | } | |
1449 | ||
1450 | tr->data[cpu]->skipped_entries = entries; | |
1451 | } | |
1452 | ||
d7350c3f FW |
1453 | /* |
1454 | * No necessary locking here. The worst thing which can | |
1455 | * happen is loosing events consumed at the same time | |
1456 | * by a trace_pipe reader. | |
1457 | * Other than that, we don't risk to crash the ring buffer | |
1458 | * because it serializes the readers. | |
1459 | * | |
1460 | * The current tracer is copied to avoid a global locking | |
1461 | * all around. | |
1462 | */ | |
bc0c38d1 SR |
1463 | static void *s_start(struct seq_file *m, loff_t *pos) |
1464 | { | |
1465 | struct trace_iterator *iter = m->private; | |
d7350c3f | 1466 | static struct tracer *old_tracer; |
b04cc6b1 | 1467 | int cpu_file = iter->cpu_file; |
bc0c38d1 SR |
1468 | void *p = NULL; |
1469 | loff_t l = 0; | |
3928a8a2 | 1470 | int cpu; |
bc0c38d1 | 1471 | |
d7350c3f | 1472 | /* copy the tracer to avoid using a global lock all around */ |
bc0c38d1 | 1473 | mutex_lock(&trace_types_lock); |
d7350c3f FW |
1474 | if (unlikely(old_tracer != current_trace && current_trace)) { |
1475 | old_tracer = current_trace; | |
1476 | *iter->trace = *current_trace; | |
d15f57f2 | 1477 | } |
d7350c3f | 1478 | mutex_unlock(&trace_types_lock); |
bc0c38d1 SR |
1479 | |
1480 | atomic_inc(&trace_record_cmdline_disabled); | |
1481 | ||
bc0c38d1 SR |
1482 | if (*pos != iter->pos) { |
1483 | iter->ent = NULL; | |
1484 | iter->cpu = 0; | |
1485 | iter->idx = -1; | |
1486 | ||
d769041f SR |
1487 | ftrace_disable_cpu(); |
1488 | ||
b04cc6b1 FW |
1489 | if (cpu_file == TRACE_PIPE_ALL_CPU) { |
1490 | for_each_tracing_cpu(cpu) | |
2f26ebd5 | 1491 | tracing_iter_reset(iter, cpu); |
b04cc6b1 | 1492 | } else |
2f26ebd5 | 1493 | tracing_iter_reset(iter, cpu_file); |
bc0c38d1 | 1494 | |
d769041f SR |
1495 | ftrace_enable_cpu(); |
1496 | ||
bc0c38d1 SR |
1497 | for (p = iter; p && l < *pos; p = s_next(m, p, &l)) |
1498 | ; | |
1499 | ||
1500 | } else { | |
4c11d7ae | 1501 | l = *pos - 1; |
bc0c38d1 SR |
1502 | p = s_next(m, p, &l); |
1503 | } | |
1504 | ||
4f535968 | 1505 | trace_event_read_lock(); |
bc0c38d1 SR |
1506 | return p; |
1507 | } | |
1508 | ||
1509 | static void s_stop(struct seq_file *m, void *p) | |
1510 | { | |
bc0c38d1 | 1511 | atomic_dec(&trace_record_cmdline_disabled); |
4f535968 | 1512 | trace_event_read_unlock(); |
bc0c38d1 SR |
1513 | } |
1514 | ||
e309b41d | 1515 | static void print_lat_help_header(struct seq_file *m) |
bc0c38d1 | 1516 | { |
a6168353 ME |
1517 | seq_puts(m, "# _------=> CPU# \n"); |
1518 | seq_puts(m, "# / _-----=> irqs-off \n"); | |
1519 | seq_puts(m, "# | / _----=> need-resched \n"); | |
1520 | seq_puts(m, "# || / _---=> hardirq/softirq \n"); | |
1521 | seq_puts(m, "# ||| / _--=> preempt-depth \n"); | |
1522 | seq_puts(m, "# |||| / \n"); | |
1523 | seq_puts(m, "# ||||| delay \n"); | |
1524 | seq_puts(m, "# cmd pid ||||| time | caller \n"); | |
1525 | seq_puts(m, "# \\ / ||||| \\ | / \n"); | |
bc0c38d1 SR |
1526 | } |
1527 | ||
e309b41d | 1528 | static void print_func_help_header(struct seq_file *m) |
bc0c38d1 | 1529 | { |
a6168353 ME |
1530 | seq_puts(m, "# TASK-PID CPU# TIMESTAMP FUNCTION\n"); |
1531 | seq_puts(m, "# | | | | |\n"); | |
bc0c38d1 SR |
1532 | } |
1533 | ||
1534 | ||
e309b41d | 1535 | static void |
bc0c38d1 SR |
1536 | print_trace_header(struct seq_file *m, struct trace_iterator *iter) |
1537 | { | |
1538 | unsigned long sym_flags = (trace_flags & TRACE_ITER_SYM_MASK); | |
1539 | struct trace_array *tr = iter->tr; | |
1540 | struct trace_array_cpu *data = tr->data[tr->cpu]; | |
1541 | struct tracer *type = current_trace; | |
2f26ebd5 SR |
1542 | unsigned long entries = 0; |
1543 | unsigned long total = 0; | |
1544 | unsigned long count; | |
bc0c38d1 | 1545 | const char *name = "preemption"; |
2f26ebd5 | 1546 | int cpu; |
bc0c38d1 SR |
1547 | |
1548 | if (type) | |
1549 | name = type->name; | |
1550 | ||
2f26ebd5 SR |
1551 | |
1552 | for_each_tracing_cpu(cpu) { | |
1553 | count = ring_buffer_entries_cpu(tr->buffer, cpu); | |
1554 | /* | |
1555 | * If this buffer has skipped entries, then we hold all | |
1556 | * entries for the trace and we need to ignore the | |
1557 | * ones before the time stamp. | |
1558 | */ | |
1559 | if (tr->data[cpu]->skipped_entries) { | |
1560 | count -= tr->data[cpu]->skipped_entries; | |
1561 | /* total is the same as the entries */ | |
1562 | total += count; | |
1563 | } else | |
1564 | total += count + | |
1565 | ring_buffer_overrun_cpu(tr->buffer, cpu); | |
1566 | entries += count; | |
1567 | } | |
bc0c38d1 | 1568 | |
888b55dc | 1569 | seq_printf(m, "# %s latency trace v1.1.5 on %s\n", |
bc0c38d1 | 1570 | name, UTS_RELEASE); |
888b55dc | 1571 | seq_puts(m, "# -----------------------------------" |
bc0c38d1 | 1572 | "---------------------------------\n"); |
888b55dc | 1573 | seq_printf(m, "# latency: %lu us, #%lu/%lu, CPU#%d |" |
bc0c38d1 | 1574 | " (M:%s VP:%d, KP:%d, SP:%d HP:%d", |
57f50be1 | 1575 | nsecs_to_usecs(data->saved_latency), |
bc0c38d1 | 1576 | entries, |
4c11d7ae | 1577 | total, |
bc0c38d1 SR |
1578 | tr->cpu, |
1579 | #if defined(CONFIG_PREEMPT_NONE) | |
1580 | "server", | |
1581 | #elif defined(CONFIG_PREEMPT_VOLUNTARY) | |
1582 | "desktop", | |
b5c21b45 | 1583 | #elif defined(CONFIG_PREEMPT) |
bc0c38d1 SR |
1584 | "preempt", |
1585 | #else | |
1586 | "unknown", | |
1587 | #endif | |
1588 | /* These are reserved for later use */ | |
1589 | 0, 0, 0, 0); | |
1590 | #ifdef CONFIG_SMP | |
1591 | seq_printf(m, " #P:%d)\n", num_online_cpus()); | |
1592 | #else | |
1593 | seq_puts(m, ")\n"); | |
1594 | #endif | |
888b55dc KM |
1595 | seq_puts(m, "# -----------------\n"); |
1596 | seq_printf(m, "# | task: %.16s-%d " | |
bc0c38d1 SR |
1597 | "(uid:%d nice:%ld policy:%ld rt_prio:%ld)\n", |
1598 | data->comm, data->pid, data->uid, data->nice, | |
1599 | data->policy, data->rt_priority); | |
888b55dc | 1600 | seq_puts(m, "# -----------------\n"); |
bc0c38d1 SR |
1601 | |
1602 | if (data->critical_start) { | |
888b55dc | 1603 | seq_puts(m, "# => started at: "); |
214023c3 SR |
1604 | seq_print_ip_sym(&iter->seq, data->critical_start, sym_flags); |
1605 | trace_print_seq(m, &iter->seq); | |
888b55dc | 1606 | seq_puts(m, "\n# => ended at: "); |
214023c3 SR |
1607 | seq_print_ip_sym(&iter->seq, data->critical_end, sym_flags); |
1608 | trace_print_seq(m, &iter->seq); | |
8248ac05 | 1609 | seq_puts(m, "\n#\n"); |
bc0c38d1 SR |
1610 | } |
1611 | ||
888b55dc | 1612 | seq_puts(m, "#\n"); |
bc0c38d1 SR |
1613 | } |
1614 | ||
a309720c SR |
1615 | static void test_cpu_buff_start(struct trace_iterator *iter) |
1616 | { | |
1617 | struct trace_seq *s = &iter->seq; | |
1618 | ||
12ef7d44 SR |
1619 | if (!(trace_flags & TRACE_ITER_ANNOTATE)) |
1620 | return; | |
1621 | ||
1622 | if (!(iter->iter_flags & TRACE_FILE_ANNOTATE)) | |
1623 | return; | |
1624 | ||
4462344e | 1625 | if (cpumask_test_cpu(iter->cpu, iter->started)) |
a309720c SR |
1626 | return; |
1627 | ||
2f26ebd5 SR |
1628 | if (iter->tr->data[iter->cpu]->skipped_entries) |
1629 | return; | |
1630 | ||
4462344e | 1631 | cpumask_set_cpu(iter->cpu, iter->started); |
b0dfa978 FW |
1632 | |
1633 | /* Don't print started cpu buffer for the first entry of the trace */ | |
1634 | if (iter->idx > 1) | |
1635 | trace_seq_printf(s, "##### CPU %u buffer started ####\n", | |
1636 | iter->cpu); | |
a309720c SR |
1637 | } |
1638 | ||
2c4f035f | 1639 | static enum print_line_t print_trace_fmt(struct trace_iterator *iter) |
bc0c38d1 | 1640 | { |
214023c3 | 1641 | struct trace_seq *s = &iter->seq; |
bc0c38d1 | 1642 | unsigned long sym_flags = (trace_flags & TRACE_ITER_SYM_MASK); |
4e3c3333 | 1643 | struct trace_entry *entry; |
f633cef0 | 1644 | struct trace_event *event; |
bc0c38d1 | 1645 | |
4e3c3333 | 1646 | entry = iter->ent; |
dd0e545f | 1647 | |
a309720c SR |
1648 | test_cpu_buff_start(iter); |
1649 | ||
c4a8e8be | 1650 | event = ftrace_find_event(entry->type); |
bc0c38d1 | 1651 | |
c4a8e8be | 1652 | if (trace_flags & TRACE_ITER_CONTEXT_INFO) { |
27d48be8 SR |
1653 | if (iter->iter_flags & TRACE_FILE_LAT_FMT) { |
1654 | if (!trace_print_lat_context(iter)) | |
1655 | goto partial; | |
1656 | } else { | |
1657 | if (!trace_print_context(iter)) | |
1658 | goto partial; | |
1659 | } | |
c4a8e8be | 1660 | } |
bc0c38d1 | 1661 | |
268ccda0 | 1662 | if (event) |
d9793bd8 ACM |
1663 | return event->trace(iter, sym_flags); |
1664 | ||
1665 | if (!trace_seq_printf(s, "Unknown type %d\n", entry->type)) | |
1666 | goto partial; | |
02b67518 | 1667 | |
2c4f035f | 1668 | return TRACE_TYPE_HANDLED; |
d9793bd8 ACM |
1669 | partial: |
1670 | return TRACE_TYPE_PARTIAL_LINE; | |
bc0c38d1 SR |
1671 | } |
1672 | ||
2c4f035f | 1673 | static enum print_line_t print_raw_fmt(struct trace_iterator *iter) |
f9896bf3 IM |
1674 | { |
1675 | struct trace_seq *s = &iter->seq; | |
1676 | struct trace_entry *entry; | |
f633cef0 | 1677 | struct trace_event *event; |
f9896bf3 IM |
1678 | |
1679 | entry = iter->ent; | |
dd0e545f | 1680 | |
c4a8e8be | 1681 | if (trace_flags & TRACE_ITER_CONTEXT_INFO) { |
d9793bd8 ACM |
1682 | if (!trace_seq_printf(s, "%d %d %llu ", |
1683 | entry->pid, iter->cpu, iter->ts)) | |
1684 | goto partial; | |
c4a8e8be | 1685 | } |
f9896bf3 | 1686 | |
f633cef0 | 1687 | event = ftrace_find_event(entry->type); |
268ccda0 | 1688 | if (event) |
d9793bd8 ACM |
1689 | return event->raw(iter, 0); |
1690 | ||
1691 | if (!trace_seq_printf(s, "%d ?\n", entry->type)) | |
1692 | goto partial; | |
777e208d | 1693 | |
2c4f035f | 1694 | return TRACE_TYPE_HANDLED; |
d9793bd8 ACM |
1695 | partial: |
1696 | return TRACE_TYPE_PARTIAL_LINE; | |
f9896bf3 IM |
1697 | } |
1698 | ||
2c4f035f | 1699 | static enum print_line_t print_hex_fmt(struct trace_iterator *iter) |
5e3ca0ec IM |
1700 | { |
1701 | struct trace_seq *s = &iter->seq; | |
1702 | unsigned char newline = '\n'; | |
1703 | struct trace_entry *entry; | |
f633cef0 | 1704 | struct trace_event *event; |
5e3ca0ec IM |
1705 | |
1706 | entry = iter->ent; | |
dd0e545f | 1707 | |
c4a8e8be FW |
1708 | if (trace_flags & TRACE_ITER_CONTEXT_INFO) { |
1709 | SEQ_PUT_HEX_FIELD_RET(s, entry->pid); | |
1710 | SEQ_PUT_HEX_FIELD_RET(s, iter->cpu); | |
1711 | SEQ_PUT_HEX_FIELD_RET(s, iter->ts); | |
1712 | } | |
5e3ca0ec | 1713 | |
f633cef0 | 1714 | event = ftrace_find_event(entry->type); |
268ccda0 | 1715 | if (event) { |
ae7462b4 | 1716 | enum print_line_t ret = event->hex(iter, 0); |
d9793bd8 ACM |
1717 | if (ret != TRACE_TYPE_HANDLED) |
1718 | return ret; | |
1719 | } | |
7104f300 | 1720 | |
5e3ca0ec IM |
1721 | SEQ_PUT_FIELD_RET(s, newline); |
1722 | ||
2c4f035f | 1723 | return TRACE_TYPE_HANDLED; |
5e3ca0ec IM |
1724 | } |
1725 | ||
2c4f035f | 1726 | static enum print_line_t print_bin_fmt(struct trace_iterator *iter) |
cb0f12aa IM |
1727 | { |
1728 | struct trace_seq *s = &iter->seq; | |
1729 | struct trace_entry *entry; | |
f633cef0 | 1730 | struct trace_event *event; |
cb0f12aa IM |
1731 | |
1732 | entry = iter->ent; | |
dd0e545f | 1733 | |
c4a8e8be FW |
1734 | if (trace_flags & TRACE_ITER_CONTEXT_INFO) { |
1735 | SEQ_PUT_FIELD_RET(s, entry->pid); | |
1830b52d | 1736 | SEQ_PUT_FIELD_RET(s, iter->cpu); |
c4a8e8be FW |
1737 | SEQ_PUT_FIELD_RET(s, iter->ts); |
1738 | } | |
cb0f12aa | 1739 | |
f633cef0 | 1740 | event = ftrace_find_event(entry->type); |
268ccda0 | 1741 | return event ? event->binary(iter, 0) : TRACE_TYPE_HANDLED; |
cb0f12aa IM |
1742 | } |
1743 | ||
bc0c38d1 SR |
1744 | static int trace_empty(struct trace_iterator *iter) |
1745 | { | |
bc0c38d1 SR |
1746 | int cpu; |
1747 | ||
9aba60fe SR |
1748 | /* If we are looking at one CPU buffer, only check that one */ |
1749 | if (iter->cpu_file != TRACE_PIPE_ALL_CPU) { | |
1750 | cpu = iter->cpu_file; | |
1751 | if (iter->buffer_iter[cpu]) { | |
1752 | if (!ring_buffer_iter_empty(iter->buffer_iter[cpu])) | |
1753 | return 0; | |
1754 | } else { | |
1755 | if (!ring_buffer_empty_cpu(iter->tr->buffer, cpu)) | |
1756 | return 0; | |
1757 | } | |
1758 | return 1; | |
1759 | } | |
1760 | ||
ab46428c | 1761 | for_each_tracing_cpu(cpu) { |
d769041f SR |
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 | } | |
bc0c38d1 | 1769 | } |
d769041f | 1770 | |
797d3712 | 1771 | return 1; |
bc0c38d1 SR |
1772 | } |
1773 | ||
4f535968 | 1774 | /* Called with trace_event_read_lock() held. */ |
2c4f035f | 1775 | static enum print_line_t print_trace_line(struct trace_iterator *iter) |
f9896bf3 | 1776 | { |
2c4f035f FW |
1777 | enum print_line_t ret; |
1778 | ||
1779 | if (iter->trace && iter->trace->print_line) { | |
1780 | ret = iter->trace->print_line(iter); | |
1781 | if (ret != TRACE_TYPE_UNHANDLED) | |
1782 | return ret; | |
1783 | } | |
72829bc3 | 1784 | |
48ead020 FW |
1785 | if (iter->ent->type == TRACE_BPRINT && |
1786 | trace_flags & TRACE_ITER_PRINTK && | |
1787 | trace_flags & TRACE_ITER_PRINTK_MSGONLY) | |
5ef841f6 | 1788 | return trace_print_bprintk_msg_only(iter); |
48ead020 | 1789 | |
66896a85 FW |
1790 | if (iter->ent->type == TRACE_PRINT && |
1791 | trace_flags & TRACE_ITER_PRINTK && | |
1792 | trace_flags & TRACE_ITER_PRINTK_MSGONLY) | |
5ef841f6 | 1793 | return trace_print_printk_msg_only(iter); |
66896a85 | 1794 | |
cb0f12aa IM |
1795 | if (trace_flags & TRACE_ITER_BIN) |
1796 | return print_bin_fmt(iter); | |
1797 | ||
5e3ca0ec IM |
1798 | if (trace_flags & TRACE_ITER_HEX) |
1799 | return print_hex_fmt(iter); | |
1800 | ||
f9896bf3 IM |
1801 | if (trace_flags & TRACE_ITER_RAW) |
1802 | return print_raw_fmt(iter); | |
1803 | ||
f9896bf3 IM |
1804 | return print_trace_fmt(iter); |
1805 | } | |
1806 | ||
bc0c38d1 SR |
1807 | static int s_show(struct seq_file *m, void *v) |
1808 | { | |
1809 | struct trace_iterator *iter = v; | |
1810 | ||
1811 | if (iter->ent == NULL) { | |
1812 | if (iter->tr) { | |
1813 | seq_printf(m, "# tracer: %s\n", iter->trace->name); | |
1814 | seq_puts(m, "#\n"); | |
1815 | } | |
8bba1bf5 MM |
1816 | if (iter->trace && iter->trace->print_header) |
1817 | iter->trace->print_header(m); | |
1818 | else if (iter->iter_flags & TRACE_FILE_LAT_FMT) { | |
bc0c38d1 SR |
1819 | /* print nothing if the buffers are empty */ |
1820 | if (trace_empty(iter)) | |
1821 | return 0; | |
1822 | print_trace_header(m, iter); | |
1823 | if (!(trace_flags & TRACE_ITER_VERBOSE)) | |
1824 | print_lat_help_header(m); | |
1825 | } else { | |
1826 | if (!(trace_flags & TRACE_ITER_VERBOSE)) | |
1827 | print_func_help_header(m); | |
1828 | } | |
1829 | } else { | |
f9896bf3 | 1830 | print_trace_line(iter); |
214023c3 | 1831 | trace_print_seq(m, &iter->seq); |
bc0c38d1 SR |
1832 | } |
1833 | ||
1834 | return 0; | |
1835 | } | |
1836 | ||
1837 | static struct seq_operations tracer_seq_ops = { | |
4bf39a94 IM |
1838 | .start = s_start, |
1839 | .next = s_next, | |
1840 | .stop = s_stop, | |
1841 | .show = s_show, | |
bc0c38d1 SR |
1842 | }; |
1843 | ||
e309b41d | 1844 | static struct trace_iterator * |
85a2f9b4 | 1845 | __tracing_open(struct inode *inode, struct file *file) |
bc0c38d1 | 1846 | { |
b04cc6b1 | 1847 | long cpu_file = (long) inode->i_private; |
85a2f9b4 | 1848 | void *fail_ret = ERR_PTR(-ENOMEM); |
bc0c38d1 | 1849 | struct trace_iterator *iter; |
3928a8a2 | 1850 | struct seq_file *m; |
85a2f9b4 | 1851 | int cpu, ret; |
bc0c38d1 | 1852 | |
85a2f9b4 SR |
1853 | if (tracing_disabled) |
1854 | return ERR_PTR(-ENODEV); | |
60a11774 | 1855 | |
bc0c38d1 | 1856 | iter = kzalloc(sizeof(*iter), GFP_KERNEL); |
85a2f9b4 SR |
1857 | if (!iter) |
1858 | return ERR_PTR(-ENOMEM); | |
bc0c38d1 | 1859 | |
d7350c3f FW |
1860 | /* |
1861 | * We make a copy of the current tracer to avoid concurrent | |
1862 | * changes on it while we are reading. | |
1863 | */ | |
bc0c38d1 | 1864 | mutex_lock(&trace_types_lock); |
d7350c3f | 1865 | iter->trace = kzalloc(sizeof(*iter->trace), GFP_KERNEL); |
85a2f9b4 | 1866 | if (!iter->trace) |
d7350c3f | 1867 | goto fail; |
85a2f9b4 | 1868 | |
d7350c3f FW |
1869 | if (current_trace) |
1870 | *iter->trace = *current_trace; | |
1871 | ||
b0dfa978 FW |
1872 | if (!alloc_cpumask_var(&iter->started, GFP_KERNEL)) |
1873 | goto fail; | |
1874 | ||
1875 | cpumask_clear(iter->started); | |
1876 | ||
bc0c38d1 SR |
1877 | if (current_trace && current_trace->print_max) |
1878 | iter->tr = &max_tr; | |
1879 | else | |
b04cc6b1 | 1880 | iter->tr = &global_trace; |
bc0c38d1 | 1881 | iter->pos = -1; |
d7350c3f | 1882 | mutex_init(&iter->mutex); |
b04cc6b1 | 1883 | iter->cpu_file = cpu_file; |
bc0c38d1 | 1884 | |
8bba1bf5 MM |
1885 | /* Notify the tracer early; before we stop tracing. */ |
1886 | if (iter->trace && iter->trace->open) | |
a93751ca | 1887 | iter->trace->open(iter); |
8bba1bf5 | 1888 | |
12ef7d44 SR |
1889 | /* Annotate start of buffers if we had overruns */ |
1890 | if (ring_buffer_overruns(iter->tr->buffer)) | |
1891 | iter->iter_flags |= TRACE_FILE_ANNOTATE; | |
1892 | ||
2f26ebd5 SR |
1893 | /* stop the trace while dumping */ |
1894 | tracing_stop(); | |
1895 | ||
b04cc6b1 FW |
1896 | if (iter->cpu_file == TRACE_PIPE_ALL_CPU) { |
1897 | for_each_tracing_cpu(cpu) { | |
12ef7d44 | 1898 | |
b04cc6b1 FW |
1899 | iter->buffer_iter[cpu] = |
1900 | ring_buffer_read_start(iter->tr->buffer, cpu); | |
2f26ebd5 | 1901 | tracing_iter_reset(iter, cpu); |
b04cc6b1 FW |
1902 | } |
1903 | } else { | |
1904 | cpu = iter->cpu_file; | |
3928a8a2 | 1905 | iter->buffer_iter[cpu] = |
b04cc6b1 | 1906 | ring_buffer_read_start(iter->tr->buffer, cpu); |
2f26ebd5 | 1907 | tracing_iter_reset(iter, cpu); |
3928a8a2 SR |
1908 | } |
1909 | ||
85a2f9b4 SR |
1910 | ret = seq_open(file, &tracer_seq_ops); |
1911 | if (ret < 0) { | |
1912 | fail_ret = ERR_PTR(ret); | |
3928a8a2 | 1913 | goto fail_buffer; |
85a2f9b4 | 1914 | } |
bc0c38d1 | 1915 | |
3928a8a2 SR |
1916 | m = file->private_data; |
1917 | m->private = iter; | |
bc0c38d1 | 1918 | |
bc0c38d1 SR |
1919 | mutex_unlock(&trace_types_lock); |
1920 | ||
bc0c38d1 | 1921 | return iter; |
3928a8a2 SR |
1922 | |
1923 | fail_buffer: | |
1924 | for_each_tracing_cpu(cpu) { | |
1925 | if (iter->buffer_iter[cpu]) | |
1926 | ring_buffer_read_finish(iter->buffer_iter[cpu]); | |
1927 | } | |
b0dfa978 | 1928 | free_cpumask_var(iter->started); |
2f26ebd5 | 1929 | tracing_start(); |
d7350c3f | 1930 | fail: |
3928a8a2 | 1931 | mutex_unlock(&trace_types_lock); |
d7350c3f | 1932 | kfree(iter->trace); |
0bb943c7 | 1933 | kfree(iter); |
3928a8a2 | 1934 | |
85a2f9b4 | 1935 | return fail_ret; |
bc0c38d1 SR |
1936 | } |
1937 | ||
1938 | int tracing_open_generic(struct inode *inode, struct file *filp) | |
1939 | { | |
60a11774 SR |
1940 | if (tracing_disabled) |
1941 | return -ENODEV; | |
1942 | ||
bc0c38d1 SR |
1943 | filp->private_data = inode->i_private; |
1944 | return 0; | |
1945 | } | |
1946 | ||
4fd27358 | 1947 | static int tracing_release(struct inode *inode, struct file *file) |
bc0c38d1 SR |
1948 | { |
1949 | struct seq_file *m = (struct seq_file *)file->private_data; | |
4acd4d00 | 1950 | struct trace_iterator *iter; |
3928a8a2 | 1951 | int cpu; |
bc0c38d1 | 1952 | |
4acd4d00 SR |
1953 | if (!(file->f_mode & FMODE_READ)) |
1954 | return 0; | |
1955 | ||
1956 | iter = m->private; | |
1957 | ||
bc0c38d1 | 1958 | mutex_lock(&trace_types_lock); |
3928a8a2 SR |
1959 | for_each_tracing_cpu(cpu) { |
1960 | if (iter->buffer_iter[cpu]) | |
1961 | ring_buffer_read_finish(iter->buffer_iter[cpu]); | |
1962 | } | |
1963 | ||
bc0c38d1 SR |
1964 | if (iter->trace && iter->trace->close) |
1965 | iter->trace->close(iter); | |
1966 | ||
1967 | /* reenable tracing if it was previously enabled */ | |
9036990d | 1968 | tracing_start(); |
bc0c38d1 SR |
1969 | mutex_unlock(&trace_types_lock); |
1970 | ||
1971 | seq_release(inode, file); | |
d7350c3f | 1972 | mutex_destroy(&iter->mutex); |
b0dfa978 | 1973 | free_cpumask_var(iter->started); |
d7350c3f | 1974 | kfree(iter->trace); |
bc0c38d1 SR |
1975 | kfree(iter); |
1976 | return 0; | |
1977 | } | |
1978 | ||
1979 | static int tracing_open(struct inode *inode, struct file *file) | |
1980 | { | |
85a2f9b4 SR |
1981 | struct trace_iterator *iter; |
1982 | int ret = 0; | |
bc0c38d1 | 1983 | |
4acd4d00 SR |
1984 | /* If this file was open for write, then erase contents */ |
1985 | if ((file->f_mode & FMODE_WRITE) && | |
8650ae32 | 1986 | (file->f_flags & O_TRUNC)) { |
4acd4d00 | 1987 | long cpu = (long) inode->i_private; |
bc0c38d1 | 1988 | |
4acd4d00 SR |
1989 | if (cpu == TRACE_PIPE_ALL_CPU) |
1990 | tracing_reset_online_cpus(&global_trace); | |
1991 | else | |
1992 | tracing_reset(&global_trace, cpu); | |
1993 | } | |
bc0c38d1 | 1994 | |
4acd4d00 SR |
1995 | if (file->f_mode & FMODE_READ) { |
1996 | iter = __tracing_open(inode, file); | |
1997 | if (IS_ERR(iter)) | |
1998 | ret = PTR_ERR(iter); | |
1999 | else if (trace_flags & TRACE_ITER_LATENCY_FMT) | |
2000 | iter->iter_flags |= TRACE_FILE_LAT_FMT; | |
2001 | } | |
bc0c38d1 SR |
2002 | return ret; |
2003 | } | |
2004 | ||
e309b41d | 2005 | static void * |
bc0c38d1 SR |
2006 | t_next(struct seq_file *m, void *v, loff_t *pos) |
2007 | { | |
f129e965 | 2008 | struct tracer *t = v; |
bc0c38d1 SR |
2009 | |
2010 | (*pos)++; | |
2011 | ||
2012 | if (t) | |
2013 | t = t->next; | |
2014 | ||
bc0c38d1 SR |
2015 | return t; |
2016 | } | |
2017 | ||
2018 | static void *t_start(struct seq_file *m, loff_t *pos) | |
2019 | { | |
f129e965 | 2020 | struct tracer *t; |
bc0c38d1 SR |
2021 | loff_t l = 0; |
2022 | ||
2023 | mutex_lock(&trace_types_lock); | |
f129e965 | 2024 | for (t = trace_types; t && l < *pos; t = t_next(m, t, &l)) |
bc0c38d1 SR |
2025 | ; |
2026 | ||
2027 | return t; | |
2028 | } | |
2029 | ||
2030 | static void t_stop(struct seq_file *m, void *p) | |
2031 | { | |
2032 | mutex_unlock(&trace_types_lock); | |
2033 | } | |
2034 | ||
2035 | static int t_show(struct seq_file *m, void *v) | |
2036 | { | |
2037 | struct tracer *t = v; | |
2038 | ||
2039 | if (!t) | |
2040 | return 0; | |
2041 | ||
2042 | seq_printf(m, "%s", t->name); | |
2043 | if (t->next) | |
2044 | seq_putc(m, ' '); | |
2045 | else | |
2046 | seq_putc(m, '\n'); | |
2047 | ||
2048 | return 0; | |
2049 | } | |
2050 | ||
2051 | static struct seq_operations show_traces_seq_ops = { | |
4bf39a94 IM |
2052 | .start = t_start, |
2053 | .next = t_next, | |
2054 | .stop = t_stop, | |
2055 | .show = t_show, | |
bc0c38d1 SR |
2056 | }; |
2057 | ||
2058 | static int show_traces_open(struct inode *inode, struct file *file) | |
2059 | { | |
60a11774 SR |
2060 | if (tracing_disabled) |
2061 | return -ENODEV; | |
2062 | ||
f129e965 | 2063 | return seq_open(file, &show_traces_seq_ops); |
bc0c38d1 SR |
2064 | } |
2065 | ||
4acd4d00 SR |
2066 | static ssize_t |
2067 | tracing_write_stub(struct file *filp, const char __user *ubuf, | |
2068 | size_t count, loff_t *ppos) | |
2069 | { | |
2070 | return count; | |
2071 | } | |
2072 | ||
5e2336a0 | 2073 | static const struct file_operations tracing_fops = { |
4bf39a94 IM |
2074 | .open = tracing_open, |
2075 | .read = seq_read, | |
4acd4d00 | 2076 | .write = tracing_write_stub, |
4bf39a94 IM |
2077 | .llseek = seq_lseek, |
2078 | .release = tracing_release, | |
bc0c38d1 SR |
2079 | }; |
2080 | ||
5e2336a0 | 2081 | static const struct file_operations show_traces_fops = { |
c7078de1 IM |
2082 | .open = show_traces_open, |
2083 | .read = seq_read, | |
2084 | .release = seq_release, | |
2085 | }; | |
2086 | ||
36dfe925 IM |
2087 | /* |
2088 | * Only trace on a CPU if the bitmask is set: | |
2089 | */ | |
9e01c1b7 | 2090 | static cpumask_var_t tracing_cpumask; |
36dfe925 IM |
2091 | |
2092 | /* | |
2093 | * The tracer itself will not take this lock, but still we want | |
2094 | * to provide a consistent cpumask to user-space: | |
2095 | */ | |
2096 | static DEFINE_MUTEX(tracing_cpumask_update_lock); | |
2097 | ||
2098 | /* | |
2099 | * Temporary storage for the character representation of the | |
2100 | * CPU bitmask (and one more byte for the newline): | |
2101 | */ | |
2102 | static char mask_str[NR_CPUS + 1]; | |
2103 | ||
c7078de1 IM |
2104 | static ssize_t |
2105 | tracing_cpumask_read(struct file *filp, char __user *ubuf, | |
2106 | size_t count, loff_t *ppos) | |
2107 | { | |
36dfe925 | 2108 | int len; |
c7078de1 IM |
2109 | |
2110 | mutex_lock(&tracing_cpumask_update_lock); | |
36dfe925 | 2111 | |
9e01c1b7 | 2112 | len = cpumask_scnprintf(mask_str, count, tracing_cpumask); |
36dfe925 IM |
2113 | if (count - len < 2) { |
2114 | count = -EINVAL; | |
2115 | goto out_err; | |
2116 | } | |
2117 | len += sprintf(mask_str + len, "\n"); | |
2118 | count = simple_read_from_buffer(ubuf, count, ppos, mask_str, NR_CPUS+1); | |
2119 | ||
2120 | out_err: | |
c7078de1 IM |
2121 | mutex_unlock(&tracing_cpumask_update_lock); |
2122 | ||
2123 | return count; | |
2124 | } | |
2125 | ||
2126 | static ssize_t | |
2127 | tracing_cpumask_write(struct file *filp, const char __user *ubuf, | |
2128 | size_t count, loff_t *ppos) | |
2129 | { | |
36dfe925 | 2130 | int err, cpu; |
9e01c1b7 RR |
2131 | cpumask_var_t tracing_cpumask_new; |
2132 | ||
2133 | if (!alloc_cpumask_var(&tracing_cpumask_new, GFP_KERNEL)) | |
2134 | return -ENOMEM; | |
c7078de1 | 2135 | |
9e01c1b7 | 2136 | err = cpumask_parse_user(ubuf, count, tracing_cpumask_new); |
c7078de1 | 2137 | if (err) |
36dfe925 IM |
2138 | goto err_unlock; |
2139 | ||
215368e8 LZ |
2140 | mutex_lock(&tracing_cpumask_update_lock); |
2141 | ||
a5e25883 | 2142 | local_irq_disable(); |
92205c23 | 2143 | __raw_spin_lock(&ftrace_max_lock); |
ab46428c | 2144 | for_each_tracing_cpu(cpu) { |
36dfe925 IM |
2145 | /* |
2146 | * Increase/decrease the disabled counter if we are | |
2147 | * about to flip a bit in the cpumask: | |
2148 | */ | |
9e01c1b7 RR |
2149 | if (cpumask_test_cpu(cpu, tracing_cpumask) && |
2150 | !cpumask_test_cpu(cpu, tracing_cpumask_new)) { | |
36dfe925 IM |
2151 | atomic_inc(&global_trace.data[cpu]->disabled); |
2152 | } | |
9e01c1b7 RR |
2153 | if (!cpumask_test_cpu(cpu, tracing_cpumask) && |
2154 | cpumask_test_cpu(cpu, tracing_cpumask_new)) { | |
36dfe925 IM |
2155 | atomic_dec(&global_trace.data[cpu]->disabled); |
2156 | } | |
2157 | } | |
92205c23 | 2158 | __raw_spin_unlock(&ftrace_max_lock); |
a5e25883 | 2159 | local_irq_enable(); |
36dfe925 | 2160 | |
9e01c1b7 | 2161 | cpumask_copy(tracing_cpumask, tracing_cpumask_new); |
36dfe925 IM |
2162 | |
2163 | mutex_unlock(&tracing_cpumask_update_lock); | |
9e01c1b7 | 2164 | free_cpumask_var(tracing_cpumask_new); |
c7078de1 IM |
2165 | |
2166 | return count; | |
36dfe925 IM |
2167 | |
2168 | err_unlock: | |
215368e8 | 2169 | free_cpumask_var(tracing_cpumask_new); |
36dfe925 IM |
2170 | |
2171 | return err; | |
c7078de1 IM |
2172 | } |
2173 | ||
5e2336a0 | 2174 | static const struct file_operations tracing_cpumask_fops = { |
c7078de1 IM |
2175 | .open = tracing_open_generic, |
2176 | .read = tracing_cpumask_read, | |
2177 | .write = tracing_cpumask_write, | |
bc0c38d1 SR |
2178 | }; |
2179 | ||
2180 | static ssize_t | |
ee6bce52 | 2181 | tracing_trace_options_read(struct file *filp, char __user *ubuf, |
bc0c38d1 SR |
2182 | size_t cnt, loff_t *ppos) |
2183 | { | |
d8e83d26 SR |
2184 | struct tracer_opt *trace_opts; |
2185 | u32 tracer_flags; | |
2186 | int len = 0; | |
bc0c38d1 SR |
2187 | char *buf; |
2188 | int r = 0; | |
d8e83d26 | 2189 | int i; |
adf9f195 | 2190 | |
bc0c38d1 | 2191 | |
c3706f00 | 2192 | /* calculate max size */ |
bc0c38d1 SR |
2193 | for (i = 0; trace_options[i]; i++) { |
2194 | len += strlen(trace_options[i]); | |
5c6a3ae1 | 2195 | len += 3; /* "no" and newline */ |
bc0c38d1 SR |
2196 | } |
2197 | ||
d8e83d26 SR |
2198 | mutex_lock(&trace_types_lock); |
2199 | tracer_flags = current_trace->flags->val; | |
2200 | trace_opts = current_trace->flags->opts; | |
2201 | ||
adf9f195 FW |
2202 | /* |
2203 | * Increase the size with names of options specific | |
2204 | * of the current tracer. | |
2205 | */ | |
2206 | for (i = 0; trace_opts[i].name; i++) { | |
2207 | len += strlen(trace_opts[i].name); | |
5c6a3ae1 | 2208 | len += 3; /* "no" and newline */ |
adf9f195 FW |
2209 | } |
2210 | ||
ff4e9da2 XG |
2211 | /* +1 for \0 */ |
2212 | buf = kmalloc(len + 1, GFP_KERNEL); | |
d8e83d26 SR |
2213 | if (!buf) { |
2214 | mutex_unlock(&trace_types_lock); | |
bc0c38d1 | 2215 | return -ENOMEM; |
d8e83d26 | 2216 | } |
bc0c38d1 SR |
2217 | |
2218 | for (i = 0; trace_options[i]; i++) { | |
2219 | if (trace_flags & (1 << i)) | |
5c6a3ae1 | 2220 | r += sprintf(buf + r, "%s\n", trace_options[i]); |
bc0c38d1 | 2221 | else |
5c6a3ae1 | 2222 | r += sprintf(buf + r, "no%s\n", trace_options[i]); |
bc0c38d1 SR |
2223 | } |
2224 | ||
adf9f195 FW |
2225 | for (i = 0; trace_opts[i].name; i++) { |
2226 | if (tracer_flags & trace_opts[i].bit) | |
5c6a3ae1 | 2227 | r += sprintf(buf + r, "%s\n", |
adf9f195 FW |
2228 | trace_opts[i].name); |
2229 | else | |
5c6a3ae1 | 2230 | r += sprintf(buf + r, "no%s\n", |
adf9f195 FW |
2231 | trace_opts[i].name); |
2232 | } | |
d8e83d26 | 2233 | mutex_unlock(&trace_types_lock); |
adf9f195 | 2234 | |
ff4e9da2 | 2235 | WARN_ON(r >= len + 1); |
bc0c38d1 | 2236 | |
36dfe925 | 2237 | r = simple_read_from_buffer(ubuf, cnt, ppos, buf, r); |
bc0c38d1 SR |
2238 | |
2239 | kfree(buf); | |
bc0c38d1 SR |
2240 | return r; |
2241 | } | |
2242 | ||
adf9f195 FW |
2243 | /* Try to assign a tracer specific option */ |
2244 | static int set_tracer_option(struct tracer *trace, char *cmp, int neg) | |
2245 | { | |
7770841e | 2246 | struct tracer_flags *tracer_flags = trace->flags; |
adf9f195 FW |
2247 | struct tracer_opt *opts = NULL; |
2248 | int ret = 0, i = 0; | |
2249 | int len; | |
2250 | ||
7770841e Z |
2251 | for (i = 0; tracer_flags->opts[i].name; i++) { |
2252 | opts = &tracer_flags->opts[i]; | |
adf9f195 FW |
2253 | len = strlen(opts->name); |
2254 | ||
2255 | if (strncmp(cmp, opts->name, len) == 0) { | |
7770841e | 2256 | ret = trace->set_flag(tracer_flags->val, |
adf9f195 FW |
2257 | opts->bit, !neg); |
2258 | break; | |
2259 | } | |
2260 | } | |
2261 | /* Not found */ | |
7770841e | 2262 | if (!tracer_flags->opts[i].name) |
adf9f195 FW |
2263 | return -EINVAL; |
2264 | ||
2265 | /* Refused to handle */ | |
2266 | if (ret) | |
2267 | return ret; | |
2268 | ||
2269 | if (neg) | |
7770841e | 2270 | tracer_flags->val &= ~opts->bit; |
adf9f195 | 2271 | else |
7770841e | 2272 | tracer_flags->val |= opts->bit; |
adf9f195 FW |
2273 | |
2274 | return 0; | |
2275 | } | |
2276 | ||
af4617bd SR |
2277 | static void set_tracer_flags(unsigned int mask, int enabled) |
2278 | { | |
2279 | /* do nothing if flag is already set */ | |
2280 | if (!!(trace_flags & mask) == !!enabled) | |
2281 | return; | |
2282 | ||
2283 | if (enabled) | |
2284 | trace_flags |= mask; | |
2285 | else | |
2286 | trace_flags &= ~mask; | |
af4617bd SR |
2287 | } |
2288 | ||
bc0c38d1 | 2289 | static ssize_t |
ee6bce52 | 2290 | tracing_trace_options_write(struct file *filp, const char __user *ubuf, |
bc0c38d1 SR |
2291 | size_t cnt, loff_t *ppos) |
2292 | { | |
2293 | char buf[64]; | |
2294 | char *cmp = buf; | |
2295 | int neg = 0; | |
adf9f195 | 2296 | int ret; |
bc0c38d1 SR |
2297 | int i; |
2298 | ||
cffae437 SR |
2299 | if (cnt >= sizeof(buf)) |
2300 | return -EINVAL; | |
bc0c38d1 SR |
2301 | |
2302 | if (copy_from_user(&buf, ubuf, cnt)) | |
2303 | return -EFAULT; | |
2304 | ||
2305 | buf[cnt] = 0; | |
2306 | ||
2307 | if (strncmp(buf, "no", 2) == 0) { | |
2308 | neg = 1; | |
2309 | cmp += 2; | |
2310 | } | |
2311 | ||
2312 | for (i = 0; trace_options[i]; i++) { | |
2313 | int len = strlen(trace_options[i]); | |
2314 | ||
2315 | if (strncmp(cmp, trace_options[i], len) == 0) { | |
af4617bd | 2316 | set_tracer_flags(1 << i, !neg); |
bc0c38d1 SR |
2317 | break; |
2318 | } | |
2319 | } | |
adf9f195 FW |
2320 | |
2321 | /* If no option could be set, test the specific tracer options */ | |
2322 | if (!trace_options[i]) { | |
d8e83d26 | 2323 | mutex_lock(&trace_types_lock); |
adf9f195 | 2324 | ret = set_tracer_option(current_trace, cmp, neg); |
d8e83d26 | 2325 | mutex_unlock(&trace_types_lock); |
adf9f195 FW |
2326 | if (ret) |
2327 | return ret; | |
2328 | } | |
bc0c38d1 SR |
2329 | |
2330 | filp->f_pos += cnt; | |
2331 | ||
2332 | return cnt; | |
2333 | } | |
2334 | ||
5e2336a0 | 2335 | static const struct file_operations tracing_iter_fops = { |
c7078de1 | 2336 | .open = tracing_open_generic, |
ee6bce52 SR |
2337 | .read = tracing_trace_options_read, |
2338 | .write = tracing_trace_options_write, | |
bc0c38d1 SR |
2339 | }; |
2340 | ||
7bd2f24c IM |
2341 | static const char readme_msg[] = |
2342 | "tracing mini-HOWTO:\n\n" | |
156f5a78 GL |
2343 | "# mount -t debugfs nodev /sys/kernel/debug\n\n" |
2344 | "# cat /sys/kernel/debug/tracing/available_tracers\n" | |
bc2b6871 | 2345 | "wakeup preemptirqsoff preemptoff irqsoff function sched_switch nop\n\n" |
156f5a78 | 2346 | "# cat /sys/kernel/debug/tracing/current_tracer\n" |
bc2b6871 | 2347 | "nop\n" |
156f5a78 GL |
2348 | "# echo sched_switch > /sys/kernel/debug/tracing/current_tracer\n" |
2349 | "# cat /sys/kernel/debug/tracing/current_tracer\n" | |
7bd2f24c | 2350 | "sched_switch\n" |
156f5a78 | 2351 | "# cat /sys/kernel/debug/tracing/trace_options\n" |
7bd2f24c | 2352 | "noprint-parent nosym-offset nosym-addr noverbose\n" |
156f5a78 GL |
2353 | "# echo print-parent > /sys/kernel/debug/tracing/trace_options\n" |
2354 | "# echo 1 > /sys/kernel/debug/tracing/tracing_enabled\n" | |
2355 | "# cat /sys/kernel/debug/tracing/trace > /tmp/trace.txt\n" | |
2356 | "# echo 0 > /sys/kernel/debug/tracing/tracing_enabled\n" | |
7bd2f24c IM |
2357 | ; |
2358 | ||
2359 | static ssize_t | |
2360 | tracing_readme_read(struct file *filp, char __user *ubuf, | |
2361 | size_t cnt, loff_t *ppos) | |
2362 | { | |
2363 | return simple_read_from_buffer(ubuf, cnt, ppos, | |
2364 | readme_msg, strlen(readme_msg)); | |
2365 | } | |
2366 | ||
5e2336a0 | 2367 | static const struct file_operations tracing_readme_fops = { |
c7078de1 IM |
2368 | .open = tracing_open_generic, |
2369 | .read = tracing_readme_read, | |
7bd2f24c IM |
2370 | }; |
2371 | ||
69abe6a5 AP |
2372 | static ssize_t |
2373 | tracing_saved_cmdlines_read(struct file *file, char __user *ubuf, | |
2374 | size_t cnt, loff_t *ppos) | |
2375 | { | |
2376 | char *buf_comm; | |
2377 | char *file_buf; | |
2378 | char *buf; | |
2379 | int len = 0; | |
2380 | int pid; | |
2381 | int i; | |
2382 | ||
2383 | file_buf = kmalloc(SAVED_CMDLINES*(16+TASK_COMM_LEN), GFP_KERNEL); | |
2384 | if (!file_buf) | |
2385 | return -ENOMEM; | |
2386 | ||
2387 | buf_comm = kmalloc(TASK_COMM_LEN, GFP_KERNEL); | |
2388 | if (!buf_comm) { | |
2389 | kfree(file_buf); | |
2390 | return -ENOMEM; | |
2391 | } | |
2392 | ||
2393 | buf = file_buf; | |
2394 | ||
2395 | for (i = 0; i < SAVED_CMDLINES; i++) { | |
2396 | int r; | |
2397 | ||
2398 | pid = map_cmdline_to_pid[i]; | |
2399 | if (pid == -1 || pid == NO_CMDLINE_MAP) | |
2400 | continue; | |
2401 | ||
2402 | trace_find_cmdline(pid, buf_comm); | |
2403 | r = sprintf(buf, "%d %s\n", pid, buf_comm); | |
2404 | buf += r; | |
2405 | len += r; | |
2406 | } | |
2407 | ||
2408 | len = simple_read_from_buffer(ubuf, cnt, ppos, | |
2409 | file_buf, len); | |
2410 | ||
2411 | kfree(file_buf); | |
2412 | kfree(buf_comm); | |
2413 | ||
2414 | return len; | |
2415 | } | |
2416 | ||
2417 | static const struct file_operations tracing_saved_cmdlines_fops = { | |
2418 | .open = tracing_open_generic, | |
2419 | .read = tracing_saved_cmdlines_read, | |
2420 | }; | |
2421 | ||
bc0c38d1 SR |
2422 | static ssize_t |
2423 | tracing_ctrl_read(struct file *filp, char __user *ubuf, | |
2424 | size_t cnt, loff_t *ppos) | |
2425 | { | |
bc0c38d1 SR |
2426 | char buf[64]; |
2427 | int r; | |
2428 | ||
9036990d | 2429 | r = sprintf(buf, "%u\n", tracer_enabled); |
4e3c3333 | 2430 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, r); |
bc0c38d1 SR |
2431 | } |
2432 | ||
2433 | static ssize_t | |
2434 | tracing_ctrl_write(struct file *filp, const char __user *ubuf, | |
2435 | size_t cnt, loff_t *ppos) | |
2436 | { | |
2437 | struct trace_array *tr = filp->private_data; | |
bc0c38d1 | 2438 | char buf[64]; |
5e39841c | 2439 | unsigned long val; |
c6caeeb1 | 2440 | int ret; |
bc0c38d1 | 2441 | |
cffae437 SR |
2442 | if (cnt >= sizeof(buf)) |
2443 | return -EINVAL; | |
bc0c38d1 SR |
2444 | |
2445 | if (copy_from_user(&buf, ubuf, cnt)) | |
2446 | return -EFAULT; | |
2447 | ||
2448 | buf[cnt] = 0; | |
2449 | ||
c6caeeb1 SR |
2450 | ret = strict_strtoul(buf, 10, &val); |
2451 | if (ret < 0) | |
2452 | return ret; | |
bc0c38d1 SR |
2453 | |
2454 | val = !!val; | |
2455 | ||
2456 | mutex_lock(&trace_types_lock); | |
9036990d SR |
2457 | if (tracer_enabled ^ val) { |
2458 | if (val) { | |
bc0c38d1 | 2459 | tracer_enabled = 1; |
9036990d SR |
2460 | if (current_trace->start) |
2461 | current_trace->start(tr); | |
2462 | tracing_start(); | |
2463 | } else { | |
bc0c38d1 | 2464 | tracer_enabled = 0; |
9036990d SR |
2465 | tracing_stop(); |
2466 | if (current_trace->stop) | |
2467 | current_trace->stop(tr); | |
2468 | } | |
bc0c38d1 SR |
2469 | } |
2470 | mutex_unlock(&trace_types_lock); | |
2471 | ||
2472 | filp->f_pos += cnt; | |
2473 | ||
2474 | return cnt; | |
2475 | } | |
2476 | ||
2477 | static ssize_t | |
2478 | tracing_set_trace_read(struct file *filp, char __user *ubuf, | |
2479 | size_t cnt, loff_t *ppos) | |
2480 | { | |
2481 | char buf[max_tracer_type_len+2]; | |
2482 | int r; | |
2483 | ||
2484 | mutex_lock(&trace_types_lock); | |
2485 | if (current_trace) | |
2486 | r = sprintf(buf, "%s\n", current_trace->name); | |
2487 | else | |
2488 | r = sprintf(buf, "\n"); | |
2489 | mutex_unlock(&trace_types_lock); | |
2490 | ||
4bf39a94 | 2491 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, r); |
bc0c38d1 SR |
2492 | } |
2493 | ||
b6f11df2 ACM |
2494 | int tracer_init(struct tracer *t, struct trace_array *tr) |
2495 | { | |
2496 | tracing_reset_online_cpus(tr); | |
2497 | return t->init(tr); | |
2498 | } | |
2499 | ||
73c5162a SR |
2500 | static int tracing_resize_ring_buffer(unsigned long size) |
2501 | { | |
2502 | int ret; | |
2503 | ||
2504 | /* | |
2505 | * If kernel or user changes the size of the ring buffer | |
a123c52b SR |
2506 | * we use the size that was given, and we can forget about |
2507 | * expanding it later. | |
73c5162a SR |
2508 | */ |
2509 | ring_buffer_expanded = 1; | |
2510 | ||
2511 | ret = ring_buffer_resize(global_trace.buffer, size); | |
2512 | if (ret < 0) | |
2513 | return ret; | |
2514 | ||
2515 | ret = ring_buffer_resize(max_tr.buffer, size); | |
2516 | if (ret < 0) { | |
2517 | int r; | |
2518 | ||
2519 | r = ring_buffer_resize(global_trace.buffer, | |
2520 | global_trace.entries); | |
2521 | if (r < 0) { | |
a123c52b SR |
2522 | /* |
2523 | * AARGH! We are left with different | |
2524 | * size max buffer!!!! | |
2525 | * The max buffer is our "snapshot" buffer. | |
2526 | * When a tracer needs a snapshot (one of the | |
2527 | * latency tracers), it swaps the max buffer | |
2528 | * with the saved snap shot. We succeeded to | |
2529 | * update the size of the main buffer, but failed to | |
2530 | * update the size of the max buffer. But when we tried | |
2531 | * to reset the main buffer to the original size, we | |
2532 | * failed there too. This is very unlikely to | |
2533 | * happen, but if it does, warn and kill all | |
2534 | * tracing. | |
2535 | */ | |
73c5162a SR |
2536 | WARN_ON(1); |
2537 | tracing_disabled = 1; | |
2538 | } | |
2539 | return ret; | |
2540 | } | |
2541 | ||
2542 | global_trace.entries = size; | |
2543 | ||
2544 | return ret; | |
2545 | } | |
2546 | ||
1852fcce SR |
2547 | /** |
2548 | * tracing_update_buffers - used by tracing facility to expand ring buffers | |
2549 | * | |
2550 | * To save on memory when the tracing is never used on a system with it | |
2551 | * configured in. The ring buffers are set to a minimum size. But once | |
2552 | * a user starts to use the tracing facility, then they need to grow | |
2553 | * to their default size. | |
2554 | * | |
2555 | * This function is to be called when a tracer is about to be used. | |
2556 | */ | |
2557 | int tracing_update_buffers(void) | |
2558 | { | |
2559 | int ret = 0; | |
2560 | ||
1027fcb2 | 2561 | mutex_lock(&trace_types_lock); |
1852fcce SR |
2562 | if (!ring_buffer_expanded) |
2563 | ret = tracing_resize_ring_buffer(trace_buf_size); | |
1027fcb2 | 2564 | mutex_unlock(&trace_types_lock); |
1852fcce SR |
2565 | |
2566 | return ret; | |
2567 | } | |
2568 | ||
577b785f SR |
2569 | struct trace_option_dentry; |
2570 | ||
2571 | static struct trace_option_dentry * | |
2572 | create_trace_option_files(struct tracer *tracer); | |
2573 | ||
2574 | static void | |
2575 | destroy_trace_option_files(struct trace_option_dentry *topts); | |
2576 | ||
b2821ae6 | 2577 | static int tracing_set_tracer(const char *buf) |
bc0c38d1 | 2578 | { |
577b785f | 2579 | static struct trace_option_dentry *topts; |
bc0c38d1 SR |
2580 | struct trace_array *tr = &global_trace; |
2581 | struct tracer *t; | |
d9e54076 | 2582 | int ret = 0; |
bc0c38d1 | 2583 | |
1027fcb2 SR |
2584 | mutex_lock(&trace_types_lock); |
2585 | ||
73c5162a SR |
2586 | if (!ring_buffer_expanded) { |
2587 | ret = tracing_resize_ring_buffer(trace_buf_size); | |
2588 | if (ret < 0) | |
59f586db | 2589 | goto out; |
73c5162a SR |
2590 | ret = 0; |
2591 | } | |
2592 | ||
bc0c38d1 SR |
2593 | for (t = trace_types; t; t = t->next) { |
2594 | if (strcmp(t->name, buf) == 0) | |
2595 | break; | |
2596 | } | |
c2931e05 FW |
2597 | if (!t) { |
2598 | ret = -EINVAL; | |
2599 | goto out; | |
2600 | } | |
2601 | if (t == current_trace) | |
bc0c38d1 SR |
2602 | goto out; |
2603 | ||
9f029e83 | 2604 | trace_branch_disable(); |
bc0c38d1 SR |
2605 | if (current_trace && current_trace->reset) |
2606 | current_trace->reset(tr); | |
2607 | ||
577b785f SR |
2608 | destroy_trace_option_files(topts); |
2609 | ||
bc0c38d1 | 2610 | current_trace = t; |
577b785f SR |
2611 | |
2612 | topts = create_trace_option_files(current_trace); | |
2613 | ||
1c80025a | 2614 | if (t->init) { |
b6f11df2 | 2615 | ret = tracer_init(t, tr); |
1c80025a FW |
2616 | if (ret) |
2617 | goto out; | |
2618 | } | |
bc0c38d1 | 2619 | |
9f029e83 | 2620 | trace_branch_enable(tr); |
bc0c38d1 SR |
2621 | out: |
2622 | mutex_unlock(&trace_types_lock); | |
2623 | ||
d9e54076 PZ |
2624 | return ret; |
2625 | } | |
2626 | ||
2627 | static ssize_t | |
2628 | tracing_set_trace_write(struct file *filp, const char __user *ubuf, | |
2629 | size_t cnt, loff_t *ppos) | |
2630 | { | |
2631 | char buf[max_tracer_type_len+1]; | |
2632 | int i; | |
2633 | size_t ret; | |
e6e7a65a FW |
2634 | int err; |
2635 | ||
2636 | ret = cnt; | |
d9e54076 PZ |
2637 | |
2638 | if (cnt > max_tracer_type_len) | |
2639 | cnt = max_tracer_type_len; | |
2640 | ||
2641 | if (copy_from_user(&buf, ubuf, cnt)) | |
2642 | return -EFAULT; | |
2643 | ||
2644 | buf[cnt] = 0; | |
2645 | ||
2646 | /* strip ending whitespace. */ | |
2647 | for (i = cnt - 1; i > 0 && isspace(buf[i]); i--) | |
2648 | buf[i] = 0; | |
2649 | ||
e6e7a65a FW |
2650 | err = tracing_set_tracer(buf); |
2651 | if (err) | |
2652 | return err; | |
d9e54076 | 2653 | |
e6e7a65a | 2654 | filp->f_pos += ret; |
bc0c38d1 | 2655 | |
c2931e05 | 2656 | return ret; |
bc0c38d1 SR |
2657 | } |
2658 | ||
2659 | static ssize_t | |
2660 | tracing_max_lat_read(struct file *filp, char __user *ubuf, | |
2661 | size_t cnt, loff_t *ppos) | |
2662 | { | |
2663 | unsigned long *ptr = filp->private_data; | |
2664 | char buf[64]; | |
2665 | int r; | |
2666 | ||
cffae437 | 2667 | r = snprintf(buf, sizeof(buf), "%ld\n", |
bc0c38d1 | 2668 | *ptr == (unsigned long)-1 ? -1 : nsecs_to_usecs(*ptr)); |
cffae437 SR |
2669 | if (r > sizeof(buf)) |
2670 | r = sizeof(buf); | |
4bf39a94 | 2671 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, r); |
bc0c38d1 SR |
2672 | } |
2673 | ||
2674 | static ssize_t | |
2675 | tracing_max_lat_write(struct file *filp, const char __user *ubuf, | |
2676 | size_t cnt, loff_t *ppos) | |
2677 | { | |
5e39841c | 2678 | unsigned long *ptr = filp->private_data; |
bc0c38d1 | 2679 | char buf[64]; |
5e39841c | 2680 | unsigned long val; |
c6caeeb1 | 2681 | int ret; |
bc0c38d1 | 2682 | |
cffae437 SR |
2683 | if (cnt >= sizeof(buf)) |
2684 | return -EINVAL; | |
bc0c38d1 SR |
2685 | |
2686 | if (copy_from_user(&buf, ubuf, cnt)) | |
2687 | return -EFAULT; | |
2688 | ||
2689 | buf[cnt] = 0; | |
2690 | ||
c6caeeb1 SR |
2691 | ret = strict_strtoul(buf, 10, &val); |
2692 | if (ret < 0) | |
2693 | return ret; | |
bc0c38d1 SR |
2694 | |
2695 | *ptr = val * 1000; | |
2696 | ||
2697 | return cnt; | |
2698 | } | |
2699 | ||
b3806b43 SR |
2700 | static int tracing_open_pipe(struct inode *inode, struct file *filp) |
2701 | { | |
b04cc6b1 | 2702 | long cpu_file = (long) inode->i_private; |
b3806b43 | 2703 | struct trace_iterator *iter; |
b04cc6b1 | 2704 | int ret = 0; |
b3806b43 SR |
2705 | |
2706 | if (tracing_disabled) | |
2707 | return -ENODEV; | |
2708 | ||
b04cc6b1 FW |
2709 | mutex_lock(&trace_types_lock); |
2710 | ||
2711 | /* We only allow one reader per cpu */ | |
2712 | if (cpu_file == TRACE_PIPE_ALL_CPU) { | |
2713 | if (!cpumask_empty(tracing_reader_cpumask)) { | |
2714 | ret = -EBUSY; | |
2715 | goto out; | |
2716 | } | |
2717 | cpumask_setall(tracing_reader_cpumask); | |
2718 | } else { | |
2719 | if (!cpumask_test_cpu(cpu_file, tracing_reader_cpumask)) | |
2720 | cpumask_set_cpu(cpu_file, tracing_reader_cpumask); | |
2721 | else { | |
2722 | ret = -EBUSY; | |
2723 | goto out; | |
2724 | } | |
b3806b43 SR |
2725 | } |
2726 | ||
2727 | /* create a buffer to store the information to pass to userspace */ | |
2728 | iter = kzalloc(sizeof(*iter), GFP_KERNEL); | |
b04cc6b1 FW |
2729 | if (!iter) { |
2730 | ret = -ENOMEM; | |
2731 | goto out; | |
2732 | } | |
b3806b43 | 2733 | |
d7350c3f FW |
2734 | /* |
2735 | * We make a copy of the current tracer to avoid concurrent | |
2736 | * changes on it while we are reading. | |
2737 | */ | |
2738 | iter->trace = kmalloc(sizeof(*iter->trace), GFP_KERNEL); | |
2739 | if (!iter->trace) { | |
2740 | ret = -ENOMEM; | |
2741 | goto fail; | |
2742 | } | |
2743 | if (current_trace) | |
2744 | *iter->trace = *current_trace; | |
2745 | ||
4462344e | 2746 | if (!alloc_cpumask_var(&iter->started, GFP_KERNEL)) { |
b04cc6b1 | 2747 | ret = -ENOMEM; |
d7350c3f | 2748 | goto fail; |
4462344e RR |
2749 | } |
2750 | ||
a309720c | 2751 | /* trace pipe does not show start of buffer */ |
4462344e | 2752 | cpumask_setall(iter->started); |
a309720c | 2753 | |
112f38a7 SR |
2754 | if (trace_flags & TRACE_ITER_LATENCY_FMT) |
2755 | iter->iter_flags |= TRACE_FILE_LAT_FMT; | |
2756 | ||
b04cc6b1 | 2757 | iter->cpu_file = cpu_file; |
b3806b43 | 2758 | iter->tr = &global_trace; |
d7350c3f | 2759 | mutex_init(&iter->mutex); |
b3806b43 SR |
2760 | filp->private_data = iter; |
2761 | ||
107bad8b SR |
2762 | if (iter->trace->pipe_open) |
2763 | iter->trace->pipe_open(iter); | |
107bad8b | 2764 | |
b04cc6b1 FW |
2765 | out: |
2766 | mutex_unlock(&trace_types_lock); | |
2767 | return ret; | |
d7350c3f FW |
2768 | |
2769 | fail: | |
2770 | kfree(iter->trace); | |
2771 | kfree(iter); | |
2772 | mutex_unlock(&trace_types_lock); | |
2773 | return ret; | |
b3806b43 SR |
2774 | } |
2775 | ||
2776 | static int tracing_release_pipe(struct inode *inode, struct file *file) | |
2777 | { | |
2778 | struct trace_iterator *iter = file->private_data; | |
2779 | ||
b04cc6b1 FW |
2780 | mutex_lock(&trace_types_lock); |
2781 | ||
2782 | if (iter->cpu_file == TRACE_PIPE_ALL_CPU) | |
2783 | cpumask_clear(tracing_reader_cpumask); | |
2784 | else | |
2785 | cpumask_clear_cpu(iter->cpu_file, tracing_reader_cpumask); | |
2786 | ||
2787 | mutex_unlock(&trace_types_lock); | |
2788 | ||
4462344e | 2789 | free_cpumask_var(iter->started); |
d7350c3f FW |
2790 | mutex_destroy(&iter->mutex); |
2791 | kfree(iter->trace); | |
b3806b43 | 2792 | kfree(iter); |
b3806b43 SR |
2793 | |
2794 | return 0; | |
2795 | } | |
2796 | ||
2a2cc8f7 SSP |
2797 | static unsigned int |
2798 | tracing_poll_pipe(struct file *filp, poll_table *poll_table) | |
2799 | { | |
2800 | struct trace_iterator *iter = filp->private_data; | |
2801 | ||
2802 | if (trace_flags & TRACE_ITER_BLOCK) { | |
2803 | /* | |
2804 | * Always select as readable when in blocking mode | |
2805 | */ | |
2806 | return POLLIN | POLLRDNORM; | |
afc2abc0 | 2807 | } else { |
2a2cc8f7 SSP |
2808 | if (!trace_empty(iter)) |
2809 | return POLLIN | POLLRDNORM; | |
2810 | poll_wait(filp, &trace_wait, poll_table); | |
2811 | if (!trace_empty(iter)) | |
2812 | return POLLIN | POLLRDNORM; | |
2813 | ||
2814 | return 0; | |
2815 | } | |
2816 | } | |
2817 | ||
6eaaa5d5 FW |
2818 | |
2819 | void default_wait_pipe(struct trace_iterator *iter) | |
2820 | { | |
2821 | DEFINE_WAIT(wait); | |
2822 | ||
2823 | prepare_to_wait(&trace_wait, &wait, TASK_INTERRUPTIBLE); | |
2824 | ||
2825 | if (trace_empty(iter)) | |
2826 | schedule(); | |
2827 | ||
2828 | finish_wait(&trace_wait, &wait); | |
2829 | } | |
2830 | ||
2831 | /* | |
2832 | * This is a make-shift waitqueue. | |
2833 | * A tracer might use this callback on some rare cases: | |
2834 | * | |
2835 | * 1) the current tracer might hold the runqueue lock when it wakes up | |
2836 | * a reader, hence a deadlock (sched, function, and function graph tracers) | |
2837 | * 2) the function tracers, trace all functions, we don't want | |
2838 | * the overhead of calling wake_up and friends | |
2839 | * (and tracing them too) | |
2840 | * | |
2841 | * Anyway, this is really very primitive wakeup. | |
2842 | */ | |
2843 | void poll_wait_pipe(struct trace_iterator *iter) | |
2844 | { | |
2845 | set_current_state(TASK_INTERRUPTIBLE); | |
2846 | /* sleep for 100 msecs, and try again. */ | |
2847 | schedule_timeout(HZ / 10); | |
2848 | } | |
2849 | ||
ff98781b EGM |
2850 | /* Must be called with trace_types_lock mutex held. */ |
2851 | static int tracing_wait_pipe(struct file *filp) | |
b3806b43 SR |
2852 | { |
2853 | struct trace_iterator *iter = filp->private_data; | |
b3806b43 | 2854 | |
b3806b43 | 2855 | while (trace_empty(iter)) { |
2dc8f095 | 2856 | |
107bad8b | 2857 | if ((filp->f_flags & O_NONBLOCK)) { |
ff98781b | 2858 | return -EAGAIN; |
107bad8b | 2859 | } |
2dc8f095 | 2860 | |
d7350c3f | 2861 | mutex_unlock(&iter->mutex); |
107bad8b | 2862 | |
6eaaa5d5 | 2863 | iter->trace->wait_pipe(iter); |
b3806b43 | 2864 | |
d7350c3f | 2865 | mutex_lock(&iter->mutex); |
107bad8b | 2866 | |
6eaaa5d5 | 2867 | if (signal_pending(current)) |
ff98781b | 2868 | return -EINTR; |
b3806b43 SR |
2869 | |
2870 | /* | |
2871 | * We block until we read something and tracing is disabled. | |
2872 | * We still block if tracing is disabled, but we have never | |
2873 | * read anything. This allows a user to cat this file, and | |
2874 | * then enable tracing. But after we have read something, | |
2875 | * we give an EOF when tracing is again disabled. | |
2876 | * | |
2877 | * iter->pos will be 0 if we haven't read anything. | |
2878 | */ | |
2879 | if (!tracer_enabled && iter->pos) | |
2880 | break; | |
b3806b43 SR |
2881 | } |
2882 | ||
ff98781b EGM |
2883 | return 1; |
2884 | } | |
2885 | ||
2886 | /* | |
2887 | * Consumer reader. | |
2888 | */ | |
2889 | static ssize_t | |
2890 | tracing_read_pipe(struct file *filp, char __user *ubuf, | |
2891 | size_t cnt, loff_t *ppos) | |
2892 | { | |
2893 | struct trace_iterator *iter = filp->private_data; | |
d7350c3f | 2894 | static struct tracer *old_tracer; |
ff98781b EGM |
2895 | ssize_t sret; |
2896 | ||
2897 | /* return any leftover data */ | |
2898 | sret = trace_seq_to_user(&iter->seq, ubuf, cnt); | |
2899 | if (sret != -EBUSY) | |
2900 | return sret; | |
2901 | ||
f9520750 | 2902 | trace_seq_init(&iter->seq); |
ff98781b | 2903 | |
d7350c3f | 2904 | /* copy the tracer to avoid using a global lock all around */ |
ff98781b | 2905 | mutex_lock(&trace_types_lock); |
d7350c3f FW |
2906 | if (unlikely(old_tracer != current_trace && current_trace)) { |
2907 | old_tracer = current_trace; | |
2908 | *iter->trace = *current_trace; | |
2909 | } | |
2910 | mutex_unlock(&trace_types_lock); | |
2911 | ||
2912 | /* | |
2913 | * Avoid more than one consumer on a single file descriptor | |
2914 | * This is just a matter of traces coherency, the ring buffer itself | |
2915 | * is protected. | |
2916 | */ | |
2917 | mutex_lock(&iter->mutex); | |
ff98781b EGM |
2918 | if (iter->trace->read) { |
2919 | sret = iter->trace->read(iter, filp, ubuf, cnt, ppos); | |
2920 | if (sret) | |
2921 | goto out; | |
2922 | } | |
2923 | ||
2924 | waitagain: | |
2925 | sret = tracing_wait_pipe(filp); | |
2926 | if (sret <= 0) | |
2927 | goto out; | |
2928 | ||
b3806b43 | 2929 | /* stop when tracing is finished */ |
ff98781b EGM |
2930 | if (trace_empty(iter)) { |
2931 | sret = 0; | |
107bad8b | 2932 | goto out; |
ff98781b | 2933 | } |
b3806b43 SR |
2934 | |
2935 | if (cnt >= PAGE_SIZE) | |
2936 | cnt = PAGE_SIZE - 1; | |
2937 | ||
53d0aa77 | 2938 | /* reset all but tr, trace, and overruns */ |
53d0aa77 SR |
2939 | memset(&iter->seq, 0, |
2940 | sizeof(struct trace_iterator) - | |
2941 | offsetof(struct trace_iterator, seq)); | |
4823ed7e | 2942 | iter->pos = -1; |
b3806b43 | 2943 | |
4f535968 | 2944 | trace_event_read_lock(); |
088b1e42 | 2945 | while (find_next_entry_inc(iter) != NULL) { |
2c4f035f | 2946 | enum print_line_t ret; |
088b1e42 SR |
2947 | int len = iter->seq.len; |
2948 | ||
f9896bf3 | 2949 | ret = print_trace_line(iter); |
2c4f035f | 2950 | if (ret == TRACE_TYPE_PARTIAL_LINE) { |
088b1e42 SR |
2951 | /* don't print partial lines */ |
2952 | iter->seq.len = len; | |
b3806b43 | 2953 | break; |
088b1e42 | 2954 | } |
b91facc3 FW |
2955 | if (ret != TRACE_TYPE_NO_CONSUME) |
2956 | trace_consume(iter); | |
b3806b43 SR |
2957 | |
2958 | if (iter->seq.len >= cnt) | |
2959 | break; | |
b3806b43 | 2960 | } |
4f535968 | 2961 | trace_event_read_unlock(); |
b3806b43 | 2962 | |
b3806b43 | 2963 | /* Now copy what we have to the user */ |
6c6c2796 PP |
2964 | sret = trace_seq_to_user(&iter->seq, ubuf, cnt); |
2965 | if (iter->seq.readpos >= iter->seq.len) | |
f9520750 | 2966 | trace_seq_init(&iter->seq); |
9ff4b974 PP |
2967 | |
2968 | /* | |
2969 | * If there was nothing to send to user, inspite of consuming trace | |
2970 | * entries, go back to wait for more entries. | |
2971 | */ | |
6c6c2796 | 2972 | if (sret == -EBUSY) |
9ff4b974 | 2973 | goto waitagain; |
b3806b43 | 2974 | |
107bad8b | 2975 | out: |
d7350c3f | 2976 | mutex_unlock(&iter->mutex); |
107bad8b | 2977 | |
6c6c2796 | 2978 | return sret; |
b3806b43 SR |
2979 | } |
2980 | ||
3c56819b EGM |
2981 | static void tracing_pipe_buf_release(struct pipe_inode_info *pipe, |
2982 | struct pipe_buffer *buf) | |
2983 | { | |
2984 | __free_page(buf->page); | |
2985 | } | |
2986 | ||
2987 | static void tracing_spd_release_pipe(struct splice_pipe_desc *spd, | |
2988 | unsigned int idx) | |
2989 | { | |
2990 | __free_page(spd->pages[idx]); | |
2991 | } | |
2992 | ||
2993 | static struct pipe_buf_operations tracing_pipe_buf_ops = { | |
34cd4998 SR |
2994 | .can_merge = 0, |
2995 | .map = generic_pipe_buf_map, | |
2996 | .unmap = generic_pipe_buf_unmap, | |
2997 | .confirm = generic_pipe_buf_confirm, | |
2998 | .release = tracing_pipe_buf_release, | |
2999 | .steal = generic_pipe_buf_steal, | |
3000 | .get = generic_pipe_buf_get, | |
3c56819b EGM |
3001 | }; |
3002 | ||
34cd4998 | 3003 | static size_t |
fa7c7f6e | 3004 | tracing_fill_pipe_page(size_t rem, struct trace_iterator *iter) |
34cd4998 SR |
3005 | { |
3006 | size_t count; | |
3007 | int ret; | |
3008 | ||
3009 | /* Seq buffer is page-sized, exactly what we need. */ | |
3010 | for (;;) { | |
3011 | count = iter->seq.len; | |
3012 | ret = print_trace_line(iter); | |
3013 | count = iter->seq.len - count; | |
3014 | if (rem < count) { | |
3015 | rem = 0; | |
3016 | iter->seq.len -= count; | |
3017 | break; | |
3018 | } | |
3019 | if (ret == TRACE_TYPE_PARTIAL_LINE) { | |
3020 | iter->seq.len -= count; | |
3021 | break; | |
3022 | } | |
3023 | ||
74e7ff8c LJ |
3024 | if (ret != TRACE_TYPE_NO_CONSUME) |
3025 | trace_consume(iter); | |
34cd4998 SR |
3026 | rem -= count; |
3027 | if (!find_next_entry_inc(iter)) { | |
3028 | rem = 0; | |
3029 | iter->ent = NULL; | |
3030 | break; | |
3031 | } | |
3032 | } | |
3033 | ||
3034 | return rem; | |
3035 | } | |
3036 | ||
3c56819b EGM |
3037 | static ssize_t tracing_splice_read_pipe(struct file *filp, |
3038 | loff_t *ppos, | |
3039 | struct pipe_inode_info *pipe, | |
3040 | size_t len, | |
3041 | unsigned int flags) | |
3042 | { | |
3043 | struct page *pages[PIPE_BUFFERS]; | |
3044 | struct partial_page partial[PIPE_BUFFERS]; | |
3045 | struct trace_iterator *iter = filp->private_data; | |
3046 | struct splice_pipe_desc spd = { | |
34cd4998 SR |
3047 | .pages = pages, |
3048 | .partial = partial, | |
3049 | .nr_pages = 0, /* This gets updated below. */ | |
3050 | .flags = flags, | |
3051 | .ops = &tracing_pipe_buf_ops, | |
3052 | .spd_release = tracing_spd_release_pipe, | |
3c56819b | 3053 | }; |
d7350c3f | 3054 | static struct tracer *old_tracer; |
3c56819b | 3055 | ssize_t ret; |
34cd4998 | 3056 | size_t rem; |
3c56819b EGM |
3057 | unsigned int i; |
3058 | ||
d7350c3f | 3059 | /* copy the tracer to avoid using a global lock all around */ |
3c56819b | 3060 | mutex_lock(&trace_types_lock); |
d7350c3f FW |
3061 | if (unlikely(old_tracer != current_trace && current_trace)) { |
3062 | old_tracer = current_trace; | |
3063 | *iter->trace = *current_trace; | |
3064 | } | |
3065 | mutex_unlock(&trace_types_lock); | |
3066 | ||
3067 | mutex_lock(&iter->mutex); | |
3c56819b EGM |
3068 | |
3069 | if (iter->trace->splice_read) { | |
3070 | ret = iter->trace->splice_read(iter, filp, | |
3071 | ppos, pipe, len, flags); | |
3072 | if (ret) | |
34cd4998 | 3073 | goto out_err; |
3c56819b EGM |
3074 | } |
3075 | ||
3076 | ret = tracing_wait_pipe(filp); | |
3077 | if (ret <= 0) | |
34cd4998 | 3078 | goto out_err; |
3c56819b EGM |
3079 | |
3080 | if (!iter->ent && !find_next_entry_inc(iter)) { | |
3081 | ret = -EFAULT; | |
34cd4998 | 3082 | goto out_err; |
3c56819b EGM |
3083 | } |
3084 | ||
4f535968 LJ |
3085 | trace_event_read_lock(); |
3086 | ||
3c56819b EGM |
3087 | /* Fill as many pages as possible. */ |
3088 | for (i = 0, rem = len; i < PIPE_BUFFERS && rem; i++) { | |
3089 | pages[i] = alloc_page(GFP_KERNEL); | |
34cd4998 SR |
3090 | if (!pages[i]) |
3091 | break; | |
3c56819b | 3092 | |
fa7c7f6e | 3093 | rem = tracing_fill_pipe_page(rem, iter); |
3c56819b EGM |
3094 | |
3095 | /* Copy the data into the page, so we can start over. */ | |
3096 | ret = trace_seq_to_buffer(&iter->seq, | |
3097 | page_address(pages[i]), | |
3098 | iter->seq.len); | |
3099 | if (ret < 0) { | |
3100 | __free_page(pages[i]); | |
3101 | break; | |
3102 | } | |
3103 | partial[i].offset = 0; | |
3104 | partial[i].len = iter->seq.len; | |
3105 | ||
f9520750 | 3106 | trace_seq_init(&iter->seq); |
3c56819b EGM |
3107 | } |
3108 | ||
4f535968 | 3109 | trace_event_read_unlock(); |
d7350c3f | 3110 | mutex_unlock(&iter->mutex); |
3c56819b EGM |
3111 | |
3112 | spd.nr_pages = i; | |
3113 | ||
3114 | return splice_to_pipe(pipe, &spd); | |
3115 | ||
34cd4998 | 3116 | out_err: |
d7350c3f | 3117 | mutex_unlock(&iter->mutex); |
3c56819b EGM |
3118 | |
3119 | return ret; | |
3120 | } | |
3121 | ||
a98a3c3f SR |
3122 | static ssize_t |
3123 | tracing_entries_read(struct file *filp, char __user *ubuf, | |
3124 | size_t cnt, loff_t *ppos) | |
3125 | { | |
3126 | struct trace_array *tr = filp->private_data; | |
db526ca3 | 3127 | char buf[96]; |
a98a3c3f SR |
3128 | int r; |
3129 | ||
db526ca3 SR |
3130 | mutex_lock(&trace_types_lock); |
3131 | if (!ring_buffer_expanded) | |
3132 | r = sprintf(buf, "%lu (expanded: %lu)\n", | |
3133 | tr->entries >> 10, | |
3134 | trace_buf_size >> 10); | |
3135 | else | |
3136 | r = sprintf(buf, "%lu\n", tr->entries >> 10); | |
3137 | mutex_unlock(&trace_types_lock); | |
3138 | ||
a98a3c3f SR |
3139 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, r); |
3140 | } | |
3141 | ||
3142 | static ssize_t | |
3143 | tracing_entries_write(struct file *filp, const char __user *ubuf, | |
3144 | size_t cnt, loff_t *ppos) | |
3145 | { | |
3146 | unsigned long val; | |
3147 | char buf[64]; | |
bf5e6519 | 3148 | int ret, cpu; |
a98a3c3f | 3149 | |
cffae437 SR |
3150 | if (cnt >= sizeof(buf)) |
3151 | return -EINVAL; | |
a98a3c3f SR |
3152 | |
3153 | if (copy_from_user(&buf, ubuf, cnt)) | |
3154 | return -EFAULT; | |
3155 | ||
3156 | buf[cnt] = 0; | |
3157 | ||
c6caeeb1 SR |
3158 | ret = strict_strtoul(buf, 10, &val); |
3159 | if (ret < 0) | |
3160 | return ret; | |
a98a3c3f SR |
3161 | |
3162 | /* must have at least 1 entry */ | |
3163 | if (!val) | |
3164 | return -EINVAL; | |
3165 | ||
3166 | mutex_lock(&trace_types_lock); | |
3167 | ||
c76f0694 | 3168 | tracing_stop(); |
a98a3c3f | 3169 | |
bf5e6519 SR |
3170 | /* disable all cpu buffers */ |
3171 | for_each_tracing_cpu(cpu) { | |
3172 | if (global_trace.data[cpu]) | |
3173 | atomic_inc(&global_trace.data[cpu]->disabled); | |
3174 | if (max_tr.data[cpu]) | |
3175 | atomic_inc(&max_tr.data[cpu]->disabled); | |
3176 | } | |
3177 | ||
1696b2b0 SR |
3178 | /* value is in KB */ |
3179 | val <<= 10; | |
3180 | ||
3928a8a2 | 3181 | if (val != global_trace.entries) { |
73c5162a | 3182 | ret = tracing_resize_ring_buffer(val); |
3928a8a2 SR |
3183 | if (ret < 0) { |
3184 | cnt = ret; | |
3eefae99 SR |
3185 | goto out; |
3186 | } | |
a98a3c3f SR |
3187 | } |
3188 | ||
3189 | filp->f_pos += cnt; | |
3190 | ||
19384c03 SR |
3191 | /* If check pages failed, return ENOMEM */ |
3192 | if (tracing_disabled) | |
3193 | cnt = -ENOMEM; | |
a98a3c3f | 3194 | out: |
bf5e6519 SR |
3195 | for_each_tracing_cpu(cpu) { |
3196 | if (global_trace.data[cpu]) | |
3197 | atomic_dec(&global_trace.data[cpu]->disabled); | |
3198 | if (max_tr.data[cpu]) | |
3199 | atomic_dec(&max_tr.data[cpu]->disabled); | |
3200 | } | |
3201 | ||
c76f0694 | 3202 | tracing_start(); |
a98a3c3f SR |
3203 | max_tr.entries = global_trace.entries; |
3204 | mutex_unlock(&trace_types_lock); | |
3205 | ||
3206 | return cnt; | |
3207 | } | |
3208 | ||
5bf9a1ee PP |
3209 | static int mark_printk(const char *fmt, ...) |
3210 | { | |
3211 | int ret; | |
3212 | va_list args; | |
3213 | va_start(args, fmt); | |
40ce74f1 | 3214 | ret = trace_vprintk(0, fmt, args); |
5bf9a1ee PP |
3215 | va_end(args); |
3216 | return ret; | |
3217 | } | |
3218 | ||
3219 | static ssize_t | |
3220 | tracing_mark_write(struct file *filp, const char __user *ubuf, | |
3221 | size_t cnt, loff_t *fpos) | |
3222 | { | |
3223 | char *buf; | |
3224 | char *end; | |
5bf9a1ee | 3225 | |
c76f0694 | 3226 | if (tracing_disabled) |
5bf9a1ee PP |
3227 | return -EINVAL; |
3228 | ||
3229 | if (cnt > TRACE_BUF_SIZE) | |
3230 | cnt = TRACE_BUF_SIZE; | |
3231 | ||
3232 | buf = kmalloc(cnt + 1, GFP_KERNEL); | |
3233 | if (buf == NULL) | |
3234 | return -ENOMEM; | |
3235 | ||
3236 | if (copy_from_user(buf, ubuf, cnt)) { | |
3237 | kfree(buf); | |
3238 | return -EFAULT; | |
3239 | } | |
3240 | ||
3241 | /* Cut from the first nil or newline. */ | |
3242 | buf[cnt] = '\0'; | |
3243 | end = strchr(buf, '\n'); | |
3244 | if (end) | |
3245 | *end = '\0'; | |
3246 | ||
3247 | cnt = mark_printk("%s\n", buf); | |
3248 | kfree(buf); | |
3249 | *fpos += cnt; | |
3250 | ||
3251 | return cnt; | |
3252 | } | |
3253 | ||
5079f326 Z |
3254 | static ssize_t tracing_clock_read(struct file *filp, char __user *ubuf, |
3255 | size_t cnt, loff_t *ppos) | |
3256 | { | |
3257 | char buf[64]; | |
3258 | int bufiter = 0; | |
3259 | int i; | |
3260 | ||
3261 | for (i = 0; i < ARRAY_SIZE(trace_clocks); i++) | |
3262 | bufiter += snprintf(buf + bufiter, sizeof(buf) - bufiter, | |
3263 | "%s%s%s%s", i ? " " : "", | |
3264 | i == trace_clock_id ? "[" : "", trace_clocks[i].name, | |
3265 | i == trace_clock_id ? "]" : ""); | |
3266 | bufiter += snprintf(buf + bufiter, sizeof(buf) - bufiter, "\n"); | |
3267 | ||
3268 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, bufiter); | |
3269 | } | |
3270 | ||
3271 | static ssize_t tracing_clock_write(struct file *filp, const char __user *ubuf, | |
3272 | size_t cnt, loff_t *fpos) | |
3273 | { | |
3274 | char buf[64]; | |
3275 | const char *clockstr; | |
3276 | int i; | |
3277 | ||
3278 | if (cnt >= sizeof(buf)) | |
3279 | return -EINVAL; | |
3280 | ||
3281 | if (copy_from_user(&buf, ubuf, cnt)) | |
3282 | return -EFAULT; | |
3283 | ||
3284 | buf[cnt] = 0; | |
3285 | ||
3286 | clockstr = strstrip(buf); | |
3287 | ||
3288 | for (i = 0; i < ARRAY_SIZE(trace_clocks); i++) { | |
3289 | if (strcmp(trace_clocks[i].name, clockstr) == 0) | |
3290 | break; | |
3291 | } | |
3292 | if (i == ARRAY_SIZE(trace_clocks)) | |
3293 | return -EINVAL; | |
3294 | ||
3295 | trace_clock_id = i; | |
3296 | ||
3297 | mutex_lock(&trace_types_lock); | |
3298 | ||
3299 | ring_buffer_set_clock(global_trace.buffer, trace_clocks[i].func); | |
3300 | if (max_tr.buffer) | |
3301 | ring_buffer_set_clock(max_tr.buffer, trace_clocks[i].func); | |
3302 | ||
3303 | mutex_unlock(&trace_types_lock); | |
3304 | ||
3305 | *fpos += cnt; | |
3306 | ||
3307 | return cnt; | |
3308 | } | |
3309 | ||
5e2336a0 | 3310 | static const struct file_operations tracing_max_lat_fops = { |
4bf39a94 IM |
3311 | .open = tracing_open_generic, |
3312 | .read = tracing_max_lat_read, | |
3313 | .write = tracing_max_lat_write, | |
bc0c38d1 SR |
3314 | }; |
3315 | ||
5e2336a0 | 3316 | static const struct file_operations tracing_ctrl_fops = { |
4bf39a94 IM |
3317 | .open = tracing_open_generic, |
3318 | .read = tracing_ctrl_read, | |
3319 | .write = tracing_ctrl_write, | |
bc0c38d1 SR |
3320 | }; |
3321 | ||
5e2336a0 | 3322 | static const struct file_operations set_tracer_fops = { |
4bf39a94 IM |
3323 | .open = tracing_open_generic, |
3324 | .read = tracing_set_trace_read, | |
3325 | .write = tracing_set_trace_write, | |
bc0c38d1 SR |
3326 | }; |
3327 | ||
5e2336a0 | 3328 | static const struct file_operations tracing_pipe_fops = { |
4bf39a94 | 3329 | .open = tracing_open_pipe, |
2a2cc8f7 | 3330 | .poll = tracing_poll_pipe, |
4bf39a94 | 3331 | .read = tracing_read_pipe, |
3c56819b | 3332 | .splice_read = tracing_splice_read_pipe, |
4bf39a94 | 3333 | .release = tracing_release_pipe, |
b3806b43 SR |
3334 | }; |
3335 | ||
5e2336a0 | 3336 | static const struct file_operations tracing_entries_fops = { |
a98a3c3f SR |
3337 | .open = tracing_open_generic, |
3338 | .read = tracing_entries_read, | |
3339 | .write = tracing_entries_write, | |
3340 | }; | |
3341 | ||
5e2336a0 | 3342 | static const struct file_operations tracing_mark_fops = { |
43a15386 | 3343 | .open = tracing_open_generic, |
5bf9a1ee PP |
3344 | .write = tracing_mark_write, |
3345 | }; | |
3346 | ||
5079f326 Z |
3347 | static const struct file_operations trace_clock_fops = { |
3348 | .open = tracing_open_generic, | |
3349 | .read = tracing_clock_read, | |
3350 | .write = tracing_clock_write, | |
3351 | }; | |
3352 | ||
2cadf913 SR |
3353 | struct ftrace_buffer_info { |
3354 | struct trace_array *tr; | |
3355 | void *spare; | |
3356 | int cpu; | |
3357 | unsigned int read; | |
3358 | }; | |
3359 | ||
3360 | static int tracing_buffers_open(struct inode *inode, struct file *filp) | |
3361 | { | |
3362 | int cpu = (int)(long)inode->i_private; | |
3363 | struct ftrace_buffer_info *info; | |
3364 | ||
3365 | if (tracing_disabled) | |
3366 | return -ENODEV; | |
3367 | ||
3368 | info = kzalloc(sizeof(*info), GFP_KERNEL); | |
3369 | if (!info) | |
3370 | return -ENOMEM; | |
3371 | ||
3372 | info->tr = &global_trace; | |
3373 | info->cpu = cpu; | |
ddd538f3 | 3374 | info->spare = NULL; |
2cadf913 SR |
3375 | /* Force reading ring buffer for first read */ |
3376 | info->read = (unsigned int)-1; | |
2cadf913 SR |
3377 | |
3378 | filp->private_data = info; | |
3379 | ||
d1e7e02f | 3380 | return nonseekable_open(inode, filp); |
2cadf913 SR |
3381 | } |
3382 | ||
3383 | static ssize_t | |
3384 | tracing_buffers_read(struct file *filp, char __user *ubuf, | |
3385 | size_t count, loff_t *ppos) | |
3386 | { | |
3387 | struct ftrace_buffer_info *info = filp->private_data; | |
3388 | unsigned int pos; | |
3389 | ssize_t ret; | |
3390 | size_t size; | |
3391 | ||
2dc5d12b SR |
3392 | if (!count) |
3393 | return 0; | |
3394 | ||
ddd538f3 LJ |
3395 | if (!info->spare) |
3396 | info->spare = ring_buffer_alloc_read_page(info->tr->buffer); | |
3397 | if (!info->spare) | |
3398 | return -ENOMEM; | |
3399 | ||
2cadf913 SR |
3400 | /* Do we have previous read data to read? */ |
3401 | if (info->read < PAGE_SIZE) | |
3402 | goto read; | |
3403 | ||
3404 | info->read = 0; | |
3405 | ||
3406 | ret = ring_buffer_read_page(info->tr->buffer, | |
3407 | &info->spare, | |
3408 | count, | |
3409 | info->cpu, 0); | |
3410 | if (ret < 0) | |
3411 | return 0; | |
3412 | ||
3413 | pos = ring_buffer_page_len(info->spare); | |
3414 | ||
3415 | if (pos < PAGE_SIZE) | |
3416 | memset(info->spare + pos, 0, PAGE_SIZE - pos); | |
3417 | ||
3418 | read: | |
3419 | size = PAGE_SIZE - info->read; | |
3420 | if (size > count) | |
3421 | size = count; | |
3422 | ||
3423 | ret = copy_to_user(ubuf, info->spare + info->read, size); | |
2dc5d12b | 3424 | if (ret == size) |
2cadf913 | 3425 | return -EFAULT; |
2dc5d12b SR |
3426 | size -= ret; |
3427 | ||
2cadf913 SR |
3428 | *ppos += size; |
3429 | info->read += size; | |
3430 | ||
3431 | return size; | |
3432 | } | |
3433 | ||
3434 | static int tracing_buffers_release(struct inode *inode, struct file *file) | |
3435 | { | |
3436 | struct ftrace_buffer_info *info = file->private_data; | |
3437 | ||
ddd538f3 LJ |
3438 | if (info->spare) |
3439 | ring_buffer_free_read_page(info->tr->buffer, info->spare); | |
2cadf913 SR |
3440 | kfree(info); |
3441 | ||
3442 | return 0; | |
3443 | } | |
3444 | ||
3445 | struct buffer_ref { | |
3446 | struct ring_buffer *buffer; | |
3447 | void *page; | |
3448 | int ref; | |
3449 | }; | |
3450 | ||
3451 | static void buffer_pipe_buf_release(struct pipe_inode_info *pipe, | |
3452 | struct pipe_buffer *buf) | |
3453 | { | |
3454 | struct buffer_ref *ref = (struct buffer_ref *)buf->private; | |
3455 | ||
3456 | if (--ref->ref) | |
3457 | return; | |
3458 | ||
3459 | ring_buffer_free_read_page(ref->buffer, ref->page); | |
3460 | kfree(ref); | |
3461 | buf->private = 0; | |
3462 | } | |
3463 | ||
3464 | static int buffer_pipe_buf_steal(struct pipe_inode_info *pipe, | |
3465 | struct pipe_buffer *buf) | |
3466 | { | |
3467 | return 1; | |
3468 | } | |
3469 | ||
3470 | static void buffer_pipe_buf_get(struct pipe_inode_info *pipe, | |
3471 | struct pipe_buffer *buf) | |
3472 | { | |
3473 | struct buffer_ref *ref = (struct buffer_ref *)buf->private; | |
3474 | ||
3475 | ref->ref++; | |
3476 | } | |
3477 | ||
3478 | /* Pipe buffer operations for a buffer. */ | |
3479 | static struct pipe_buf_operations buffer_pipe_buf_ops = { | |
3480 | .can_merge = 0, | |
3481 | .map = generic_pipe_buf_map, | |
3482 | .unmap = generic_pipe_buf_unmap, | |
3483 | .confirm = generic_pipe_buf_confirm, | |
3484 | .release = buffer_pipe_buf_release, | |
3485 | .steal = buffer_pipe_buf_steal, | |
3486 | .get = buffer_pipe_buf_get, | |
3487 | }; | |
3488 | ||
3489 | /* | |
3490 | * Callback from splice_to_pipe(), if we need to release some pages | |
3491 | * at the end of the spd in case we error'ed out in filling the pipe. | |
3492 | */ | |
3493 | static void buffer_spd_release(struct splice_pipe_desc *spd, unsigned int i) | |
3494 | { | |
3495 | struct buffer_ref *ref = | |
3496 | (struct buffer_ref *)spd->partial[i].private; | |
3497 | ||
3498 | if (--ref->ref) | |
3499 | return; | |
3500 | ||
3501 | ring_buffer_free_read_page(ref->buffer, ref->page); | |
3502 | kfree(ref); | |
3503 | spd->partial[i].private = 0; | |
3504 | } | |
3505 | ||
3506 | static ssize_t | |
3507 | tracing_buffers_splice_read(struct file *file, loff_t *ppos, | |
3508 | struct pipe_inode_info *pipe, size_t len, | |
3509 | unsigned int flags) | |
3510 | { | |
3511 | struct ftrace_buffer_info *info = file->private_data; | |
3512 | struct partial_page partial[PIPE_BUFFERS]; | |
3513 | struct page *pages[PIPE_BUFFERS]; | |
3514 | struct splice_pipe_desc spd = { | |
3515 | .pages = pages, | |
3516 | .partial = partial, | |
3517 | .flags = flags, | |
3518 | .ops = &buffer_pipe_buf_ops, | |
3519 | .spd_release = buffer_spd_release, | |
3520 | }; | |
3521 | struct buffer_ref *ref; | |
93459c6c | 3522 | int entries, size, i; |
2cadf913 SR |
3523 | size_t ret; |
3524 | ||
93cfb3c9 LJ |
3525 | if (*ppos & (PAGE_SIZE - 1)) { |
3526 | WARN_ONCE(1, "Ftrace: previous read must page-align\n"); | |
3527 | return -EINVAL; | |
3528 | } | |
3529 | ||
3530 | if (len & (PAGE_SIZE - 1)) { | |
3531 | WARN_ONCE(1, "Ftrace: splice_read should page-align\n"); | |
3532 | if (len < PAGE_SIZE) | |
3533 | return -EINVAL; | |
3534 | len &= PAGE_MASK; | |
3535 | } | |
3536 | ||
93459c6c SR |
3537 | entries = ring_buffer_entries_cpu(info->tr->buffer, info->cpu); |
3538 | ||
3539 | for (i = 0; i < PIPE_BUFFERS && len && entries; i++, len -= PAGE_SIZE) { | |
2cadf913 SR |
3540 | struct page *page; |
3541 | int r; | |
3542 | ||
3543 | ref = kzalloc(sizeof(*ref), GFP_KERNEL); | |
3544 | if (!ref) | |
3545 | break; | |
3546 | ||
7267fa68 | 3547 | ref->ref = 1; |
2cadf913 SR |
3548 | ref->buffer = info->tr->buffer; |
3549 | ref->page = ring_buffer_alloc_read_page(ref->buffer); | |
3550 | if (!ref->page) { | |
3551 | kfree(ref); | |
3552 | break; | |
3553 | } | |
3554 | ||
3555 | r = ring_buffer_read_page(ref->buffer, &ref->page, | |
f2957f1f | 3556 | len, info->cpu, 1); |
2cadf913 SR |
3557 | if (r < 0) { |
3558 | ring_buffer_free_read_page(ref->buffer, | |
3559 | ref->page); | |
3560 | kfree(ref); | |
3561 | break; | |
3562 | } | |
3563 | ||
3564 | /* | |
3565 | * zero out any left over data, this is going to | |
3566 | * user land. | |
3567 | */ | |
3568 | size = ring_buffer_page_len(ref->page); | |
3569 | if (size < PAGE_SIZE) | |
3570 | memset(ref->page + size, 0, PAGE_SIZE - size); | |
3571 | ||
3572 | page = virt_to_page(ref->page); | |
3573 | ||
3574 | spd.pages[i] = page; | |
3575 | spd.partial[i].len = PAGE_SIZE; | |
3576 | spd.partial[i].offset = 0; | |
3577 | spd.partial[i].private = (unsigned long)ref; | |
3578 | spd.nr_pages++; | |
93cfb3c9 | 3579 | *ppos += PAGE_SIZE; |
93459c6c SR |
3580 | |
3581 | entries = ring_buffer_entries_cpu(info->tr->buffer, info->cpu); | |
2cadf913 SR |
3582 | } |
3583 | ||
3584 | spd.nr_pages = i; | |
3585 | ||
3586 | /* did we read anything? */ | |
3587 | if (!spd.nr_pages) { | |
3588 | if (flags & SPLICE_F_NONBLOCK) | |
3589 | ret = -EAGAIN; | |
3590 | else | |
3591 | ret = 0; | |
3592 | /* TODO: block */ | |
3593 | return ret; | |
3594 | } | |
3595 | ||
3596 | ret = splice_to_pipe(pipe, &spd); | |
3597 | ||
3598 | return ret; | |
3599 | } | |
3600 | ||
3601 | static const struct file_operations tracing_buffers_fops = { | |
3602 | .open = tracing_buffers_open, | |
3603 | .read = tracing_buffers_read, | |
3604 | .release = tracing_buffers_release, | |
3605 | .splice_read = tracing_buffers_splice_read, | |
3606 | .llseek = no_llseek, | |
3607 | }; | |
3608 | ||
c8d77183 SR |
3609 | static ssize_t |
3610 | tracing_stats_read(struct file *filp, char __user *ubuf, | |
3611 | size_t count, loff_t *ppos) | |
3612 | { | |
3613 | unsigned long cpu = (unsigned long)filp->private_data; | |
3614 | struct trace_array *tr = &global_trace; | |
3615 | struct trace_seq *s; | |
3616 | unsigned long cnt; | |
3617 | ||
e4f2d10f | 3618 | s = kmalloc(sizeof(*s), GFP_KERNEL); |
c8d77183 SR |
3619 | if (!s) |
3620 | return ENOMEM; | |
3621 | ||
3622 | trace_seq_init(s); | |
3623 | ||
3624 | cnt = ring_buffer_entries_cpu(tr->buffer, cpu); | |
3625 | trace_seq_printf(s, "entries: %ld\n", cnt); | |
3626 | ||
3627 | cnt = ring_buffer_overrun_cpu(tr->buffer, cpu); | |
3628 | trace_seq_printf(s, "overrun: %ld\n", cnt); | |
3629 | ||
3630 | cnt = ring_buffer_commit_overrun_cpu(tr->buffer, cpu); | |
3631 | trace_seq_printf(s, "commit overrun: %ld\n", cnt); | |
3632 | ||
c8d77183 SR |
3633 | count = simple_read_from_buffer(ubuf, count, ppos, s->buffer, s->len); |
3634 | ||
3635 | kfree(s); | |
3636 | ||
3637 | return count; | |
3638 | } | |
3639 | ||
3640 | static const struct file_operations tracing_stats_fops = { | |
3641 | .open = tracing_open_generic, | |
3642 | .read = tracing_stats_read, | |
3643 | }; | |
3644 | ||
bc0c38d1 SR |
3645 | #ifdef CONFIG_DYNAMIC_FTRACE |
3646 | ||
b807c3d0 SR |
3647 | int __weak ftrace_arch_read_dyn_info(char *buf, int size) |
3648 | { | |
3649 | return 0; | |
3650 | } | |
3651 | ||
bc0c38d1 | 3652 | static ssize_t |
b807c3d0 | 3653 | tracing_read_dyn_info(struct file *filp, char __user *ubuf, |
bc0c38d1 SR |
3654 | size_t cnt, loff_t *ppos) |
3655 | { | |
a26a2a27 SR |
3656 | static char ftrace_dyn_info_buffer[1024]; |
3657 | static DEFINE_MUTEX(dyn_info_mutex); | |
bc0c38d1 | 3658 | unsigned long *p = filp->private_data; |
b807c3d0 | 3659 | char *buf = ftrace_dyn_info_buffer; |
a26a2a27 | 3660 | int size = ARRAY_SIZE(ftrace_dyn_info_buffer); |
bc0c38d1 SR |
3661 | int r; |
3662 | ||
b807c3d0 SR |
3663 | mutex_lock(&dyn_info_mutex); |
3664 | r = sprintf(buf, "%ld ", *p); | |
4bf39a94 | 3665 | |
a26a2a27 | 3666 | r += ftrace_arch_read_dyn_info(buf+r, (size-1)-r); |
b807c3d0 SR |
3667 | buf[r++] = '\n'; |
3668 | ||
3669 | r = simple_read_from_buffer(ubuf, cnt, ppos, buf, r); | |
3670 | ||
3671 | mutex_unlock(&dyn_info_mutex); | |
3672 | ||
3673 | return r; | |
bc0c38d1 SR |
3674 | } |
3675 | ||
5e2336a0 | 3676 | static const struct file_operations tracing_dyn_info_fops = { |
4bf39a94 | 3677 | .open = tracing_open_generic, |
b807c3d0 | 3678 | .read = tracing_read_dyn_info, |
bc0c38d1 SR |
3679 | }; |
3680 | #endif | |
3681 | ||
3682 | static struct dentry *d_tracer; | |
3683 | ||
3684 | struct dentry *tracing_init_dentry(void) | |
3685 | { | |
3686 | static int once; | |
3687 | ||
3688 | if (d_tracer) | |
3689 | return d_tracer; | |
3690 | ||
3e1f60b8 FW |
3691 | if (!debugfs_initialized()) |
3692 | return NULL; | |
3693 | ||
bc0c38d1 SR |
3694 | d_tracer = debugfs_create_dir("tracing", NULL); |
3695 | ||
3696 | if (!d_tracer && !once) { | |
3697 | once = 1; | |
3698 | pr_warning("Could not create debugfs directory 'tracing'\n"); | |
3699 | return NULL; | |
3700 | } | |
3701 | ||
3702 | return d_tracer; | |
3703 | } | |
3704 | ||
b04cc6b1 FW |
3705 | static struct dentry *d_percpu; |
3706 | ||
3707 | struct dentry *tracing_dentry_percpu(void) | |
3708 | { | |
3709 | static int once; | |
3710 | struct dentry *d_tracer; | |
3711 | ||
3712 | if (d_percpu) | |
3713 | return d_percpu; | |
3714 | ||
3715 | d_tracer = tracing_init_dentry(); | |
3716 | ||
3717 | if (!d_tracer) | |
3718 | return NULL; | |
3719 | ||
3720 | d_percpu = debugfs_create_dir("per_cpu", d_tracer); | |
3721 | ||
3722 | if (!d_percpu && !once) { | |
3723 | once = 1; | |
3724 | pr_warning("Could not create debugfs directory 'per_cpu'\n"); | |
3725 | return NULL; | |
3726 | } | |
3727 | ||
3728 | return d_percpu; | |
3729 | } | |
3730 | ||
3731 | static void tracing_init_debugfs_percpu(long cpu) | |
3732 | { | |
3733 | struct dentry *d_percpu = tracing_dentry_percpu(); | |
5452af66 | 3734 | struct dentry *d_cpu; |
8656e7a2 FW |
3735 | /* strlen(cpu) + MAX(log10(cpu)) + '\0' */ |
3736 | char cpu_dir[7]; | |
b04cc6b1 FW |
3737 | |
3738 | if (cpu > 999 || cpu < 0) | |
3739 | return; | |
3740 | ||
8656e7a2 FW |
3741 | sprintf(cpu_dir, "cpu%ld", cpu); |
3742 | d_cpu = debugfs_create_dir(cpu_dir, d_percpu); | |
3743 | if (!d_cpu) { | |
3744 | pr_warning("Could not create debugfs '%s' entry\n", cpu_dir); | |
3745 | return; | |
3746 | } | |
b04cc6b1 | 3747 | |
8656e7a2 | 3748 | /* per cpu trace_pipe */ |
5452af66 FW |
3749 | trace_create_file("trace_pipe", 0444, d_cpu, |
3750 | (void *) cpu, &tracing_pipe_fops); | |
b04cc6b1 FW |
3751 | |
3752 | /* per cpu trace */ | |
5452af66 FW |
3753 | trace_create_file("trace", 0644, d_cpu, |
3754 | (void *) cpu, &tracing_fops); | |
7f96f93f | 3755 | |
5452af66 FW |
3756 | trace_create_file("trace_pipe_raw", 0444, d_cpu, |
3757 | (void *) cpu, &tracing_buffers_fops); | |
7f96f93f | 3758 | |
c8d77183 SR |
3759 | trace_create_file("stats", 0444, d_cpu, |
3760 | (void *) cpu, &tracing_stats_fops); | |
b04cc6b1 FW |
3761 | } |
3762 | ||
60a11774 SR |
3763 | #ifdef CONFIG_FTRACE_SELFTEST |
3764 | /* Let selftest have access to static functions in this file */ | |
3765 | #include "trace_selftest.c" | |
3766 | #endif | |
3767 | ||
577b785f SR |
3768 | struct trace_option_dentry { |
3769 | struct tracer_opt *opt; | |
3770 | struct tracer_flags *flags; | |
3771 | struct dentry *entry; | |
3772 | }; | |
3773 | ||
3774 | static ssize_t | |
3775 | trace_options_read(struct file *filp, char __user *ubuf, size_t cnt, | |
3776 | loff_t *ppos) | |
3777 | { | |
3778 | struct trace_option_dentry *topt = filp->private_data; | |
3779 | char *buf; | |
3780 | ||
3781 | if (topt->flags->val & topt->opt->bit) | |
3782 | buf = "1\n"; | |
3783 | else | |
3784 | buf = "0\n"; | |
3785 | ||
3786 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, 2); | |
3787 | } | |
3788 | ||
3789 | static ssize_t | |
3790 | trace_options_write(struct file *filp, const char __user *ubuf, size_t cnt, | |
3791 | loff_t *ppos) | |
3792 | { | |
3793 | struct trace_option_dentry *topt = filp->private_data; | |
3794 | unsigned long val; | |
3795 | char buf[64]; | |
3796 | int ret; | |
3797 | ||
3798 | if (cnt >= sizeof(buf)) | |
3799 | return -EINVAL; | |
3800 | ||
3801 | if (copy_from_user(&buf, ubuf, cnt)) | |
3802 | return -EFAULT; | |
3803 | ||
3804 | buf[cnt] = 0; | |
3805 | ||
3806 | ret = strict_strtoul(buf, 10, &val); | |
3807 | if (ret < 0) | |
3808 | return ret; | |
3809 | ||
3810 | ret = 0; | |
3811 | switch (val) { | |
3812 | case 0: | |
3813 | /* do nothing if already cleared */ | |
3814 | if (!(topt->flags->val & topt->opt->bit)) | |
3815 | break; | |
3816 | ||
3817 | mutex_lock(&trace_types_lock); | |
3818 | if (current_trace->set_flag) | |
3819 | ret = current_trace->set_flag(topt->flags->val, | |
3820 | topt->opt->bit, 0); | |
3821 | mutex_unlock(&trace_types_lock); | |
3822 | if (ret) | |
3823 | return ret; | |
3824 | topt->flags->val &= ~topt->opt->bit; | |
3825 | break; | |
3826 | case 1: | |
3827 | /* do nothing if already set */ | |
3828 | if (topt->flags->val & topt->opt->bit) | |
3829 | break; | |
3830 | ||
3831 | mutex_lock(&trace_types_lock); | |
3832 | if (current_trace->set_flag) | |
3833 | ret = current_trace->set_flag(topt->flags->val, | |
3834 | topt->opt->bit, 1); | |
3835 | mutex_unlock(&trace_types_lock); | |
3836 | if (ret) | |
3837 | return ret; | |
3838 | topt->flags->val |= topt->opt->bit; | |
3839 | break; | |
3840 | ||
3841 | default: | |
3842 | return -EINVAL; | |
3843 | } | |
3844 | ||
3845 | *ppos += cnt; | |
3846 | ||
3847 | return cnt; | |
3848 | } | |
3849 | ||
3850 | ||
3851 | static const struct file_operations trace_options_fops = { | |
3852 | .open = tracing_open_generic, | |
3853 | .read = trace_options_read, | |
3854 | .write = trace_options_write, | |
3855 | }; | |
3856 | ||
a8259075 SR |
3857 | static ssize_t |
3858 | trace_options_core_read(struct file *filp, char __user *ubuf, size_t cnt, | |
3859 | loff_t *ppos) | |
3860 | { | |
3861 | long index = (long)filp->private_data; | |
3862 | char *buf; | |
3863 | ||
3864 | if (trace_flags & (1 << index)) | |
3865 | buf = "1\n"; | |
3866 | else | |
3867 | buf = "0\n"; | |
3868 | ||
3869 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, 2); | |
3870 | } | |
3871 | ||
3872 | static ssize_t | |
3873 | trace_options_core_write(struct file *filp, const char __user *ubuf, size_t cnt, | |
3874 | loff_t *ppos) | |
3875 | { | |
3876 | long index = (long)filp->private_data; | |
3877 | char buf[64]; | |
3878 | unsigned long val; | |
3879 | int ret; | |
3880 | ||
3881 | if (cnt >= sizeof(buf)) | |
3882 | return -EINVAL; | |
3883 | ||
3884 | if (copy_from_user(&buf, ubuf, cnt)) | |
3885 | return -EFAULT; | |
3886 | ||
3887 | buf[cnt] = 0; | |
3888 | ||
3889 | ret = strict_strtoul(buf, 10, &val); | |
3890 | if (ret < 0) | |
3891 | return ret; | |
3892 | ||
3893 | switch (val) { | |
3894 | case 0: | |
3895 | trace_flags &= ~(1 << index); | |
3896 | break; | |
3897 | case 1: | |
3898 | trace_flags |= 1 << index; | |
3899 | break; | |
3900 | ||
3901 | default: | |
3902 | return -EINVAL; | |
3903 | } | |
3904 | ||
3905 | *ppos += cnt; | |
3906 | ||
3907 | return cnt; | |
3908 | } | |
3909 | ||
a8259075 SR |
3910 | static const struct file_operations trace_options_core_fops = { |
3911 | .open = tracing_open_generic, | |
3912 | .read = trace_options_core_read, | |
3913 | .write = trace_options_core_write, | |
3914 | }; | |
3915 | ||
5452af66 FW |
3916 | struct dentry *trace_create_file(const char *name, |
3917 | mode_t mode, | |
3918 | struct dentry *parent, | |
3919 | void *data, | |
3920 | const struct file_operations *fops) | |
3921 | { | |
3922 | struct dentry *ret; | |
3923 | ||
3924 | ret = debugfs_create_file(name, mode, parent, data, fops); | |
3925 | if (!ret) | |
3926 | pr_warning("Could not create debugfs '%s' entry\n", name); | |
3927 | ||
3928 | return ret; | |
3929 | } | |
3930 | ||
3931 | ||
a8259075 SR |
3932 | static struct dentry *trace_options_init_dentry(void) |
3933 | { | |
3934 | struct dentry *d_tracer; | |
3935 | static struct dentry *t_options; | |
3936 | ||
3937 | if (t_options) | |
3938 | return t_options; | |
3939 | ||
3940 | d_tracer = tracing_init_dentry(); | |
3941 | if (!d_tracer) | |
3942 | return NULL; | |
3943 | ||
3944 | t_options = debugfs_create_dir("options", d_tracer); | |
3945 | if (!t_options) { | |
3946 | pr_warning("Could not create debugfs directory 'options'\n"); | |
3947 | return NULL; | |
3948 | } | |
3949 | ||
3950 | return t_options; | |
3951 | } | |
3952 | ||
577b785f SR |
3953 | static void |
3954 | create_trace_option_file(struct trace_option_dentry *topt, | |
3955 | struct tracer_flags *flags, | |
3956 | struct tracer_opt *opt) | |
3957 | { | |
3958 | struct dentry *t_options; | |
577b785f SR |
3959 | |
3960 | t_options = trace_options_init_dentry(); | |
3961 | if (!t_options) | |
3962 | return; | |
3963 | ||
3964 | topt->flags = flags; | |
3965 | topt->opt = opt; | |
3966 | ||
5452af66 | 3967 | topt->entry = trace_create_file(opt->name, 0644, t_options, topt, |
577b785f SR |
3968 | &trace_options_fops); |
3969 | ||
577b785f SR |
3970 | } |
3971 | ||
3972 | static struct trace_option_dentry * | |
3973 | create_trace_option_files(struct tracer *tracer) | |
3974 | { | |
3975 | struct trace_option_dentry *topts; | |
3976 | struct tracer_flags *flags; | |
3977 | struct tracer_opt *opts; | |
3978 | int cnt; | |
3979 | ||
3980 | if (!tracer) | |
3981 | return NULL; | |
3982 | ||
3983 | flags = tracer->flags; | |
3984 | ||
3985 | if (!flags || !flags->opts) | |
3986 | return NULL; | |
3987 | ||
3988 | opts = flags->opts; | |
3989 | ||
3990 | for (cnt = 0; opts[cnt].name; cnt++) | |
3991 | ; | |
3992 | ||
0cfe8245 | 3993 | topts = kcalloc(cnt + 1, sizeof(*topts), GFP_KERNEL); |
577b785f SR |
3994 | if (!topts) |
3995 | return NULL; | |
3996 | ||
3997 | for (cnt = 0; opts[cnt].name; cnt++) | |
3998 | create_trace_option_file(&topts[cnt], flags, | |
3999 | &opts[cnt]); | |
4000 | ||
4001 | return topts; | |
4002 | } | |
4003 | ||
4004 | static void | |
4005 | destroy_trace_option_files(struct trace_option_dentry *topts) | |
4006 | { | |
4007 | int cnt; | |
4008 | ||
4009 | if (!topts) | |
4010 | return; | |
4011 | ||
4012 | for (cnt = 0; topts[cnt].opt; cnt++) { | |
4013 | if (topts[cnt].entry) | |
4014 | debugfs_remove(topts[cnt].entry); | |
4015 | } | |
4016 | ||
4017 | kfree(topts); | |
4018 | } | |
4019 | ||
a8259075 SR |
4020 | static struct dentry * |
4021 | create_trace_option_core_file(const char *option, long index) | |
4022 | { | |
4023 | struct dentry *t_options; | |
a8259075 SR |
4024 | |
4025 | t_options = trace_options_init_dentry(); | |
4026 | if (!t_options) | |
4027 | return NULL; | |
4028 | ||
5452af66 | 4029 | return trace_create_file(option, 0644, t_options, (void *)index, |
a8259075 | 4030 | &trace_options_core_fops); |
a8259075 SR |
4031 | } |
4032 | ||
4033 | static __init void create_trace_options_dir(void) | |
4034 | { | |
4035 | struct dentry *t_options; | |
a8259075 SR |
4036 | int i; |
4037 | ||
4038 | t_options = trace_options_init_dentry(); | |
4039 | if (!t_options) | |
4040 | return; | |
4041 | ||
5452af66 FW |
4042 | for (i = 0; trace_options[i]; i++) |
4043 | create_trace_option_core_file(trace_options[i], i); | |
a8259075 SR |
4044 | } |
4045 | ||
b5ad384e | 4046 | static __init int tracer_init_debugfs(void) |
bc0c38d1 SR |
4047 | { |
4048 | struct dentry *d_tracer; | |
b04cc6b1 | 4049 | int cpu; |
bc0c38d1 SR |
4050 | |
4051 | d_tracer = tracing_init_dentry(); | |
4052 | ||
5452af66 FW |
4053 | trace_create_file("tracing_enabled", 0644, d_tracer, |
4054 | &global_trace, &tracing_ctrl_fops); | |
bc0c38d1 | 4055 | |
5452af66 FW |
4056 | trace_create_file("trace_options", 0644, d_tracer, |
4057 | NULL, &tracing_iter_fops); | |
bc0c38d1 | 4058 | |
5452af66 FW |
4059 | trace_create_file("tracing_cpumask", 0644, d_tracer, |
4060 | NULL, &tracing_cpumask_fops); | |
4061 | ||
4062 | trace_create_file("trace", 0644, d_tracer, | |
4063 | (void *) TRACE_PIPE_ALL_CPU, &tracing_fops); | |
a8259075 | 4064 | |
5452af66 FW |
4065 | trace_create_file("available_tracers", 0444, d_tracer, |
4066 | &global_trace, &show_traces_fops); | |
4067 | ||
339ae5d3 | 4068 | trace_create_file("current_tracer", 0644, d_tracer, |
5452af66 FW |
4069 | &global_trace, &set_tracer_fops); |
4070 | ||
5d4a9dba | 4071 | #ifdef CONFIG_TRACER_MAX_TRACE |
5452af66 FW |
4072 | trace_create_file("tracing_max_latency", 0644, d_tracer, |
4073 | &tracing_max_latency, &tracing_max_lat_fops); | |
4074 | ||
4075 | trace_create_file("tracing_thresh", 0644, d_tracer, | |
4076 | &tracing_thresh, &tracing_max_lat_fops); | |
5d4a9dba | 4077 | #endif |
a8259075 | 4078 | |
339ae5d3 | 4079 | trace_create_file("README", 0444, d_tracer, |
5452af66 FW |
4080 | NULL, &tracing_readme_fops); |
4081 | ||
4082 | trace_create_file("trace_pipe", 0444, d_tracer, | |
b04cc6b1 | 4083 | (void *) TRACE_PIPE_ALL_CPU, &tracing_pipe_fops); |
5452af66 FW |
4084 | |
4085 | trace_create_file("buffer_size_kb", 0644, d_tracer, | |
4086 | &global_trace, &tracing_entries_fops); | |
4087 | ||
4088 | trace_create_file("trace_marker", 0220, d_tracer, | |
4089 | NULL, &tracing_mark_fops); | |
5bf9a1ee | 4090 | |
69abe6a5 AP |
4091 | trace_create_file("saved_cmdlines", 0444, d_tracer, |
4092 | NULL, &tracing_saved_cmdlines_fops); | |
5bf9a1ee | 4093 | |
5079f326 Z |
4094 | trace_create_file("trace_clock", 0644, d_tracer, NULL, |
4095 | &trace_clock_fops); | |
4096 | ||
bc0c38d1 | 4097 | #ifdef CONFIG_DYNAMIC_FTRACE |
5452af66 FW |
4098 | trace_create_file("dyn_ftrace_total_info", 0444, d_tracer, |
4099 | &ftrace_update_tot_cnt, &tracing_dyn_info_fops); | |
bc0c38d1 | 4100 | #endif |
d618b3e6 IM |
4101 | #ifdef CONFIG_SYSPROF_TRACER |
4102 | init_tracer_sysprof_debugfs(d_tracer); | |
4103 | #endif | |
b04cc6b1 | 4104 | |
5452af66 FW |
4105 | create_trace_options_dir(); |
4106 | ||
b04cc6b1 FW |
4107 | for_each_tracing_cpu(cpu) |
4108 | tracing_init_debugfs_percpu(cpu); | |
4109 | ||
b5ad384e | 4110 | return 0; |
bc0c38d1 SR |
4111 | } |
4112 | ||
3f5a54e3 SR |
4113 | static int trace_panic_handler(struct notifier_block *this, |
4114 | unsigned long event, void *unused) | |
4115 | { | |
944ac425 SR |
4116 | if (ftrace_dump_on_oops) |
4117 | ftrace_dump(); | |
3f5a54e3 SR |
4118 | return NOTIFY_OK; |
4119 | } | |
4120 | ||
4121 | static struct notifier_block trace_panic_notifier = { | |
4122 | .notifier_call = trace_panic_handler, | |
4123 | .next = NULL, | |
4124 | .priority = 150 /* priority: INT_MAX >= x >= 0 */ | |
4125 | }; | |
4126 | ||
4127 | static int trace_die_handler(struct notifier_block *self, | |
4128 | unsigned long val, | |
4129 | void *data) | |
4130 | { | |
4131 | switch (val) { | |
4132 | case DIE_OOPS: | |
944ac425 SR |
4133 | if (ftrace_dump_on_oops) |
4134 | ftrace_dump(); | |
3f5a54e3 SR |
4135 | break; |
4136 | default: | |
4137 | break; | |
4138 | } | |
4139 | return NOTIFY_OK; | |
4140 | } | |
4141 | ||
4142 | static struct notifier_block trace_die_notifier = { | |
4143 | .notifier_call = trace_die_handler, | |
4144 | .priority = 200 | |
4145 | }; | |
4146 | ||
4147 | /* | |
4148 | * printk is set to max of 1024, we really don't need it that big. | |
4149 | * Nothing should be printing 1000 characters anyway. | |
4150 | */ | |
4151 | #define TRACE_MAX_PRINT 1000 | |
4152 | ||
4153 | /* | |
4154 | * Define here KERN_TRACE so that we have one place to modify | |
4155 | * it if we decide to change what log level the ftrace dump | |
4156 | * should be at. | |
4157 | */ | |
428aee14 | 4158 | #define KERN_TRACE KERN_EMERG |
3f5a54e3 SR |
4159 | |
4160 | static void | |
4161 | trace_printk_seq(struct trace_seq *s) | |
4162 | { | |
4163 | /* Probably should print a warning here. */ | |
4164 | if (s->len >= 1000) | |
4165 | s->len = 1000; | |
4166 | ||
4167 | /* should be zero ended, but we are paranoid. */ | |
4168 | s->buffer[s->len] = 0; | |
4169 | ||
4170 | printk(KERN_TRACE "%s", s->buffer); | |
4171 | ||
f9520750 | 4172 | trace_seq_init(s); |
3f5a54e3 SR |
4173 | } |
4174 | ||
cf586b61 | 4175 | static void __ftrace_dump(bool disable_tracing) |
3f5a54e3 | 4176 | { |
cd891ae0 SR |
4177 | static raw_spinlock_t ftrace_dump_lock = |
4178 | (raw_spinlock_t)__RAW_SPIN_LOCK_UNLOCKED; | |
3f5a54e3 SR |
4179 | /* use static because iter can be a bit big for the stack */ |
4180 | static struct trace_iterator iter; | |
cf586b61 | 4181 | unsigned int old_userobj; |
3f5a54e3 | 4182 | static int dump_ran; |
d769041f SR |
4183 | unsigned long flags; |
4184 | int cnt = 0, cpu; | |
3f5a54e3 SR |
4185 | |
4186 | /* only one dump */ | |
cd891ae0 SR |
4187 | local_irq_save(flags); |
4188 | __raw_spin_lock(&ftrace_dump_lock); | |
3f5a54e3 SR |
4189 | if (dump_ran) |
4190 | goto out; | |
4191 | ||
4192 | dump_ran = 1; | |
4193 | ||
0ee6b6cf | 4194 | tracing_off(); |
cf586b61 FW |
4195 | |
4196 | if (disable_tracing) | |
4197 | ftrace_kill(); | |
3f5a54e3 | 4198 | |
d769041f SR |
4199 | for_each_tracing_cpu(cpu) { |
4200 | atomic_inc(&global_trace.data[cpu]->disabled); | |
4201 | } | |
4202 | ||
cf586b61 FW |
4203 | old_userobj = trace_flags & TRACE_ITER_SYM_USEROBJ; |
4204 | ||
b54d3de9 TE |
4205 | /* don't look at user memory in panic mode */ |
4206 | trace_flags &= ~TRACE_ITER_SYM_USEROBJ; | |
4207 | ||
3f5a54e3 SR |
4208 | printk(KERN_TRACE "Dumping ftrace buffer:\n"); |
4209 | ||
e543ad76 | 4210 | /* Simulate the iterator */ |
3f5a54e3 SR |
4211 | iter.tr = &global_trace; |
4212 | iter.trace = current_trace; | |
e543ad76 | 4213 | iter.cpu_file = TRACE_PIPE_ALL_CPU; |
3f5a54e3 SR |
4214 | |
4215 | /* | |
4216 | * We need to stop all tracing on all CPUS to read the | |
4217 | * the next buffer. This is a bit expensive, but is | |
4218 | * not done often. We fill all what we can read, | |
4219 | * and then release the locks again. | |
4220 | */ | |
4221 | ||
3f5a54e3 SR |
4222 | while (!trace_empty(&iter)) { |
4223 | ||
4224 | if (!cnt) | |
4225 | printk(KERN_TRACE "---------------------------------\n"); | |
4226 | ||
4227 | cnt++; | |
4228 | ||
4229 | /* reset all but tr, trace, and overruns */ | |
4230 | memset(&iter.seq, 0, | |
4231 | sizeof(struct trace_iterator) - | |
4232 | offsetof(struct trace_iterator, seq)); | |
4233 | iter.iter_flags |= TRACE_FILE_LAT_FMT; | |
4234 | iter.pos = -1; | |
4235 | ||
4236 | if (find_next_entry_inc(&iter) != NULL) { | |
74e7ff8c LJ |
4237 | int ret; |
4238 | ||
4239 | ret = print_trace_line(&iter); | |
4240 | if (ret != TRACE_TYPE_NO_CONSUME) | |
4241 | trace_consume(&iter); | |
3f5a54e3 SR |
4242 | } |
4243 | ||
4244 | trace_printk_seq(&iter.seq); | |
4245 | } | |
4246 | ||
4247 | if (!cnt) | |
4248 | printk(KERN_TRACE " (ftrace buffer empty)\n"); | |
4249 | else | |
4250 | printk(KERN_TRACE "---------------------------------\n"); | |
4251 | ||
cf586b61 FW |
4252 | /* Re-enable tracing if requested */ |
4253 | if (!disable_tracing) { | |
4254 | trace_flags |= old_userobj; | |
4255 | ||
4256 | for_each_tracing_cpu(cpu) { | |
4257 | atomic_dec(&global_trace.data[cpu]->disabled); | |
4258 | } | |
4259 | tracing_on(); | |
4260 | } | |
4261 | ||
3f5a54e3 | 4262 | out: |
cd891ae0 SR |
4263 | __raw_spin_unlock(&ftrace_dump_lock); |
4264 | local_irq_restore(flags); | |
3f5a54e3 SR |
4265 | } |
4266 | ||
cf586b61 FW |
4267 | /* By default: disable tracing after the dump */ |
4268 | void ftrace_dump(void) | |
4269 | { | |
4270 | __ftrace_dump(true); | |
4271 | } | |
4272 | ||
3928a8a2 | 4273 | __init static int tracer_alloc_buffers(void) |
bc0c38d1 | 4274 | { |
73c5162a | 4275 | int ring_buf_size; |
4c11d7ae | 4276 | int i; |
9e01c1b7 | 4277 | int ret = -ENOMEM; |
4c11d7ae | 4278 | |
9e01c1b7 RR |
4279 | if (!alloc_cpumask_var(&tracing_buffer_mask, GFP_KERNEL)) |
4280 | goto out; | |
4281 | ||
4282 | if (!alloc_cpumask_var(&tracing_cpumask, GFP_KERNEL)) | |
4283 | goto out_free_buffer_mask; | |
4c11d7ae | 4284 | |
b04cc6b1 FW |
4285 | if (!alloc_cpumask_var(&tracing_reader_cpumask, GFP_KERNEL)) |
4286 | goto out_free_tracing_cpumask; | |
4287 | ||
73c5162a SR |
4288 | /* To save memory, keep the ring buffer size to its minimum */ |
4289 | if (ring_buffer_expanded) | |
4290 | ring_buf_size = trace_buf_size; | |
4291 | else | |
4292 | ring_buf_size = 1; | |
4293 | ||
9e01c1b7 RR |
4294 | cpumask_copy(tracing_buffer_mask, cpu_possible_mask); |
4295 | cpumask_copy(tracing_cpumask, cpu_all_mask); | |
b04cc6b1 | 4296 | cpumask_clear(tracing_reader_cpumask); |
9e01c1b7 RR |
4297 | |
4298 | /* TODO: make the number of buffers hot pluggable with CPUS */ | |
73c5162a | 4299 | global_trace.buffer = ring_buffer_alloc(ring_buf_size, |
3928a8a2 SR |
4300 | TRACE_BUFFER_FLAGS); |
4301 | if (!global_trace.buffer) { | |
4302 | printk(KERN_ERR "tracer: failed to allocate ring buffer!\n"); | |
4303 | WARN_ON(1); | |
9e01c1b7 | 4304 | goto out_free_cpumask; |
4c11d7ae | 4305 | } |
3928a8a2 | 4306 | global_trace.entries = ring_buffer_size(global_trace.buffer); |
4c11d7ae | 4307 | |
9e01c1b7 | 4308 | |
4c11d7ae | 4309 | #ifdef CONFIG_TRACER_MAX_TRACE |
73c5162a | 4310 | max_tr.buffer = ring_buffer_alloc(ring_buf_size, |
3928a8a2 SR |
4311 | TRACE_BUFFER_FLAGS); |
4312 | if (!max_tr.buffer) { | |
4313 | printk(KERN_ERR "tracer: failed to allocate max ring buffer!\n"); | |
4314 | WARN_ON(1); | |
4315 | ring_buffer_free(global_trace.buffer); | |
9e01c1b7 | 4316 | goto out_free_cpumask; |
4c11d7ae | 4317 | } |
3928a8a2 SR |
4318 | max_tr.entries = ring_buffer_size(max_tr.buffer); |
4319 | WARN_ON(max_tr.entries != global_trace.entries); | |
a98a3c3f | 4320 | #endif |
ab46428c | 4321 | |
4c11d7ae | 4322 | /* Allocate the first page for all buffers */ |
ab46428c | 4323 | for_each_tracing_cpu(i) { |
566b0aaf | 4324 | global_trace.data[i] = &per_cpu(global_trace_cpu, i); |
bc0c38d1 | 4325 | max_tr.data[i] = &per_cpu(max_data, i); |
4c11d7ae | 4326 | } |
bc0c38d1 | 4327 | |
bc0c38d1 SR |
4328 | trace_init_cmdlines(); |
4329 | ||
43a15386 | 4330 | register_tracer(&nop_trace); |
79fb0768 | 4331 | current_trace = &nop_trace; |
b5ad384e FW |
4332 | #ifdef CONFIG_BOOT_TRACER |
4333 | register_tracer(&boot_tracer); | |
b5ad384e | 4334 | #endif |
60a11774 SR |
4335 | /* All seems OK, enable tracing */ |
4336 | tracing_disabled = 0; | |
3928a8a2 | 4337 | |
3f5a54e3 SR |
4338 | atomic_notifier_chain_register(&panic_notifier_list, |
4339 | &trace_panic_notifier); | |
4340 | ||
4341 | register_die_notifier(&trace_die_notifier); | |
2fc1dfbe FW |
4342 | |
4343 | return 0; | |
3f5a54e3 | 4344 | |
9e01c1b7 | 4345 | out_free_cpumask: |
b04cc6b1 FW |
4346 | free_cpumask_var(tracing_reader_cpumask); |
4347 | out_free_tracing_cpumask: | |
9e01c1b7 RR |
4348 | free_cpumask_var(tracing_cpumask); |
4349 | out_free_buffer_mask: | |
4350 | free_cpumask_var(tracing_buffer_mask); | |
4351 | out: | |
4352 | return ret; | |
bc0c38d1 | 4353 | } |
b2821ae6 SR |
4354 | |
4355 | __init static int clear_boot_tracer(void) | |
4356 | { | |
4357 | /* | |
4358 | * The default tracer at boot buffer is an init section. | |
4359 | * This function is called in lateinit. If we did not | |
4360 | * find the boot tracer, then clear it out, to prevent | |
4361 | * later registration from accessing the buffer that is | |
4362 | * about to be freed. | |
4363 | */ | |
4364 | if (!default_bootup_tracer) | |
4365 | return 0; | |
4366 | ||
4367 | printk(KERN_INFO "ftrace bootup tracer '%s' not registered.\n", | |
4368 | default_bootup_tracer); | |
4369 | default_bootup_tracer = NULL; | |
4370 | ||
4371 | return 0; | |
4372 | } | |
4373 | ||
b5ad384e FW |
4374 | early_initcall(tracer_alloc_buffers); |
4375 | fs_initcall(tracer_init_debugfs); | |
b2821ae6 | 4376 | late_initcall(clear_boot_tracer); |