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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> | |
3f5a54e3 | 20 | #include <linux/notifier.h> |
2cadf913 | 21 | #include <linux/irqflags.h> |
bc0c38d1 | 22 | #include <linux/debugfs.h> |
4c11d7ae | 23 | #include <linux/pagemap.h> |
bc0c38d1 SR |
24 | #include <linux/hardirq.h> |
25 | #include <linux/linkage.h> | |
26 | #include <linux/uaccess.h> | |
2cadf913 | 27 | #include <linux/kprobes.h> |
bc0c38d1 SR |
28 | #include <linux/ftrace.h> |
29 | #include <linux/module.h> | |
30 | #include <linux/percpu.h> | |
2cadf913 | 31 | #include <linux/splice.h> |
3f5a54e3 | 32 | #include <linux/kdebug.h> |
5f0c6c03 | 33 | #include <linux/string.h> |
bc0c38d1 SR |
34 | #include <linux/ctype.h> |
35 | #include <linux/init.h> | |
2a2cc8f7 | 36 | #include <linux/poll.h> |
bc0c38d1 SR |
37 | #include <linux/gfp.h> |
38 | #include <linux/fs.h> | |
86387f7e | 39 | |
bc0c38d1 | 40 | #include "trace.h" |
f0868d1e | 41 | #include "trace_output.h" |
bc0c38d1 | 42 | |
3928a8a2 SR |
43 | #define TRACE_BUFFER_FLAGS (RB_FL_OVERWRITE) |
44 | ||
745b1626 | 45 | unsigned long __read_mostly tracing_max_latency; |
bc0c38d1 SR |
46 | unsigned long __read_mostly tracing_thresh; |
47 | ||
73c5162a SR |
48 | /* |
49 | * On boot up, the ring buffer is set to the minimum size, so that | |
50 | * we do not waste memory on systems that are not using tracing. | |
51 | */ | |
52 | static int ring_buffer_expanded; | |
53 | ||
8e1b82e0 FW |
54 | /* |
55 | * We need to change this state when a selftest is running. | |
ff32504f FW |
56 | * A selftest will lurk into the ring-buffer to count the |
57 | * entries inserted during the selftest although some concurrent | |
5e1607a0 | 58 | * insertions into the ring-buffer such as trace_printk could occurred |
ff32504f FW |
59 | * at the same time, giving false positive or negative results. |
60 | */ | |
8e1b82e0 | 61 | static bool __read_mostly tracing_selftest_running; |
ff32504f | 62 | |
b2821ae6 SR |
63 | /* |
64 | * If a tracer is running, we do not want to run SELFTEST. | |
65 | */ | |
66 | static bool __read_mostly tracing_selftest_disabled; | |
67 | ||
adf9f195 FW |
68 | /* For tracers that don't implement custom flags */ |
69 | static struct tracer_opt dummy_tracer_opt[] = { | |
70 | { } | |
71 | }; | |
72 | ||
73 | static struct tracer_flags dummy_tracer_flags = { | |
74 | .val = 0, | |
75 | .opts = dummy_tracer_opt | |
76 | }; | |
77 | ||
78 | static int dummy_set_flag(u32 old_flags, u32 bit, int set) | |
79 | { | |
80 | return 0; | |
81 | } | |
0f048701 SR |
82 | |
83 | /* | |
84 | * Kill all tracing for good (never come back). | |
85 | * It is initialized to 1 but will turn to zero if the initialization | |
86 | * of the tracer is successful. But that is the only place that sets | |
87 | * this back to zero. | |
88 | */ | |
4fd27358 | 89 | static int tracing_disabled = 1; |
0f048701 | 90 | |
d769041f SR |
91 | static DEFINE_PER_CPU(local_t, ftrace_cpu_disabled); |
92 | ||
93 | static inline void ftrace_disable_cpu(void) | |
94 | { | |
95 | preempt_disable(); | |
96 | local_inc(&__get_cpu_var(ftrace_cpu_disabled)); | |
97 | } | |
98 | ||
99 | static inline void ftrace_enable_cpu(void) | |
100 | { | |
101 | local_dec(&__get_cpu_var(ftrace_cpu_disabled)); | |
102 | preempt_enable(); | |
103 | } | |
104 | ||
9e01c1b7 | 105 | static cpumask_var_t __read_mostly tracing_buffer_mask; |
ab46428c | 106 | |
b04cc6b1 FW |
107 | /* Define which cpu buffers are currently read in trace_pipe */ |
108 | static cpumask_var_t tracing_reader_cpumask; | |
109 | ||
ab46428c | 110 | #define for_each_tracing_cpu(cpu) \ |
9e01c1b7 | 111 | for_each_cpu(cpu, tracing_buffer_mask) |
ab46428c | 112 | |
944ac425 SR |
113 | /* |
114 | * ftrace_dump_on_oops - variable to dump ftrace buffer on oops | |
115 | * | |
116 | * If there is an oops (or kernel panic) and the ftrace_dump_on_oops | |
117 | * is set, then ftrace_dump is called. This will output the contents | |
118 | * of the ftrace buffers to the console. This is very useful for | |
119 | * capturing traces that lead to crashes and outputing it to a | |
120 | * serial console. | |
121 | * | |
122 | * It is default off, but you can enable it with either specifying | |
123 | * "ftrace_dump_on_oops" in the kernel command line, or setting | |
124 | * /proc/sys/kernel/ftrace_dump_on_oops to true. | |
125 | */ | |
126 | int ftrace_dump_on_oops; | |
127 | ||
b2821ae6 SR |
128 | static int tracing_set_tracer(const char *buf); |
129 | ||
130 | #define BOOTUP_TRACER_SIZE 100 | |
131 | static char bootup_tracer_buf[BOOTUP_TRACER_SIZE] __initdata; | |
132 | static char *default_bootup_tracer; | |
d9e54076 PZ |
133 | |
134 | static int __init set_ftrace(char *str) | |
135 | { | |
b2821ae6 SR |
136 | strncpy(bootup_tracer_buf, str, BOOTUP_TRACER_SIZE); |
137 | default_bootup_tracer = bootup_tracer_buf; | |
73c5162a SR |
138 | /* We are using ftrace early, expand it */ |
139 | ring_buffer_expanded = 1; | |
d9e54076 PZ |
140 | return 1; |
141 | } | |
b2821ae6 | 142 | __setup("ftrace=", set_ftrace); |
d9e54076 | 143 | |
944ac425 SR |
144 | static int __init set_ftrace_dump_on_oops(char *str) |
145 | { | |
146 | ftrace_dump_on_oops = 1; | |
147 | return 1; | |
148 | } | |
149 | __setup("ftrace_dump_on_oops", set_ftrace_dump_on_oops); | |
60a11774 | 150 | |
cf8e3474 | 151 | unsigned long long ns2usecs(cycle_t nsec) |
bc0c38d1 SR |
152 | { |
153 | nsec += 500; | |
154 | do_div(nsec, 1000); | |
155 | return nsec; | |
156 | } | |
157 | ||
4fcdae83 SR |
158 | /* |
159 | * The global_trace is the descriptor that holds the tracing | |
160 | * buffers for the live tracing. For each CPU, it contains | |
161 | * a link list of pages that will store trace entries. The | |
162 | * page descriptor of the pages in the memory is used to hold | |
163 | * the link list by linking the lru item in the page descriptor | |
164 | * to each of the pages in the buffer per CPU. | |
165 | * | |
166 | * For each active CPU there is a data field that holds the | |
167 | * pages for the buffer for that CPU. Each CPU has the same number | |
168 | * of pages allocated for its buffer. | |
169 | */ | |
bc0c38d1 SR |
170 | static struct trace_array global_trace; |
171 | ||
172 | static DEFINE_PER_CPU(struct trace_array_cpu, global_trace_cpu); | |
173 | ||
eb02ce01 TZ |
174 | int filter_current_check_discard(struct ftrace_event_call *call, void *rec, |
175 | struct ring_buffer_event *event) | |
176 | { | |
177 | return filter_check_discard(call, rec, global_trace.buffer, event); | |
178 | } | |
17c873ec | 179 | EXPORT_SYMBOL_GPL(filter_current_check_discard); |
eb02ce01 | 180 | |
37886f6a SR |
181 | cycle_t ftrace_now(int cpu) |
182 | { | |
183 | u64 ts; | |
184 | ||
185 | /* Early boot up does not have a buffer yet */ | |
186 | if (!global_trace.buffer) | |
187 | return trace_clock_local(); | |
188 | ||
189 | ts = ring_buffer_time_stamp(global_trace.buffer, cpu); | |
190 | ring_buffer_normalize_time_stamp(global_trace.buffer, cpu, &ts); | |
191 | ||
192 | return ts; | |
193 | } | |
bc0c38d1 | 194 | |
4fcdae83 SR |
195 | /* |
196 | * The max_tr is used to snapshot the global_trace when a maximum | |
197 | * latency is reached. Some tracers will use this to store a maximum | |
198 | * trace while it continues examining live traces. | |
199 | * | |
200 | * The buffers for the max_tr are set up the same as the global_trace. | |
201 | * When a snapshot is taken, the link list of the max_tr is swapped | |
202 | * with the link list of the global_trace and the buffers are reset for | |
203 | * the global_trace so the tracing can continue. | |
204 | */ | |
bc0c38d1 SR |
205 | static struct trace_array max_tr; |
206 | ||
207 | static DEFINE_PER_CPU(struct trace_array_cpu, max_data); | |
208 | ||
4fcdae83 | 209 | /* tracer_enabled is used to toggle activation of a tracer */ |
26994ead | 210 | static int tracer_enabled = 1; |
4fcdae83 | 211 | |
9036990d SR |
212 | /** |
213 | * tracing_is_enabled - return tracer_enabled status | |
214 | * | |
215 | * This function is used by other tracers to know the status | |
216 | * of the tracer_enabled flag. Tracers may use this function | |
217 | * to know if it should enable their features when starting | |
218 | * up. See irqsoff tracer for an example (start_irqsoff_tracer). | |
219 | */ | |
220 | int tracing_is_enabled(void) | |
221 | { | |
222 | return tracer_enabled; | |
223 | } | |
224 | ||
4fcdae83 | 225 | /* |
3928a8a2 SR |
226 | * trace_buf_size is the size in bytes that is allocated |
227 | * for a buffer. Note, the number of bytes is always rounded | |
228 | * to page size. | |
3f5a54e3 SR |
229 | * |
230 | * This number is purposely set to a low number of 16384. | |
231 | * If the dump on oops happens, it will be much appreciated | |
232 | * to not have to wait for all that output. Anyway this can be | |
233 | * boot time and run time configurable. | |
4fcdae83 | 234 | */ |
3928a8a2 | 235 | #define TRACE_BUF_SIZE_DEFAULT 1441792UL /* 16384 * 88 (sizeof(entry)) */ |
3f5a54e3 | 236 | |
3928a8a2 | 237 | static unsigned long trace_buf_size = TRACE_BUF_SIZE_DEFAULT; |
bc0c38d1 | 238 | |
4fcdae83 | 239 | /* trace_types holds a link list of available tracers. */ |
bc0c38d1 | 240 | static struct tracer *trace_types __read_mostly; |
4fcdae83 SR |
241 | |
242 | /* current_trace points to the tracer that is currently active */ | |
bc0c38d1 | 243 | static struct tracer *current_trace __read_mostly; |
4fcdae83 SR |
244 | |
245 | /* | |
246 | * max_tracer_type_len is used to simplify the allocating of | |
247 | * buffers to read userspace tracer names. We keep track of | |
248 | * the longest tracer name registered. | |
249 | */ | |
bc0c38d1 SR |
250 | static int max_tracer_type_len; |
251 | ||
4fcdae83 SR |
252 | /* |
253 | * trace_types_lock is used to protect the trace_types list. | |
254 | * This lock is also used to keep user access serialized. | |
255 | * Accesses from userspace will grab this lock while userspace | |
256 | * activities happen inside the kernel. | |
257 | */ | |
bc0c38d1 | 258 | static DEFINE_MUTEX(trace_types_lock); |
4fcdae83 SR |
259 | |
260 | /* trace_wait is a waitqueue for tasks blocked on trace_poll */ | |
4e655519 IM |
261 | static DECLARE_WAIT_QUEUE_HEAD(trace_wait); |
262 | ||
ee6bce52 | 263 | /* trace_flags holds trace_options default values */ |
12ef7d44 | 264 | unsigned long trace_flags = TRACE_ITER_PRINT_PARENT | TRACE_ITER_PRINTK | |
a2a16d6a SR |
265 | TRACE_ITER_ANNOTATE | TRACE_ITER_CONTEXT_INFO | TRACE_ITER_SLEEP_TIME | |
266 | TRACE_ITER_GRAPH_TIME; | |
4e655519 | 267 | |
4fcdae83 SR |
268 | /** |
269 | * trace_wake_up - wake up tasks waiting for trace input | |
270 | * | |
271 | * Simply wakes up any task that is blocked on the trace_wait | |
272 | * queue. These is used with trace_poll for tasks polling the trace. | |
273 | */ | |
4e655519 IM |
274 | void trace_wake_up(void) |
275 | { | |
017730c1 IM |
276 | /* |
277 | * The runqueue_is_locked() can fail, but this is the best we | |
278 | * have for now: | |
279 | */ | |
280 | if (!(trace_flags & TRACE_ITER_BLOCK) && !runqueue_is_locked()) | |
4e655519 IM |
281 | wake_up(&trace_wait); |
282 | } | |
bc0c38d1 | 283 | |
3928a8a2 | 284 | static int __init set_buf_size(char *str) |
bc0c38d1 | 285 | { |
3928a8a2 | 286 | unsigned long buf_size; |
c6caeeb1 SR |
287 | int ret; |
288 | ||
bc0c38d1 SR |
289 | if (!str) |
290 | return 0; | |
3928a8a2 | 291 | ret = strict_strtoul(str, 0, &buf_size); |
c6caeeb1 | 292 | /* nr_entries can not be zero */ |
3928a8a2 | 293 | if (ret < 0 || buf_size == 0) |
c6caeeb1 | 294 | return 0; |
3928a8a2 | 295 | trace_buf_size = buf_size; |
bc0c38d1 SR |
296 | return 1; |
297 | } | |
3928a8a2 | 298 | __setup("trace_buf_size=", set_buf_size); |
bc0c38d1 | 299 | |
57f50be1 SR |
300 | unsigned long nsecs_to_usecs(unsigned long nsecs) |
301 | { | |
302 | return nsecs / 1000; | |
303 | } | |
304 | ||
4fcdae83 | 305 | /* These must match the bit postions in trace_iterator_flags */ |
bc0c38d1 SR |
306 | static const char *trace_options[] = { |
307 | "print-parent", | |
308 | "sym-offset", | |
309 | "sym-addr", | |
310 | "verbose", | |
f9896bf3 | 311 | "raw", |
5e3ca0ec | 312 | "hex", |
cb0f12aa | 313 | "bin", |
2a2cc8f7 | 314 | "block", |
86387f7e | 315 | "stacktrace", |
4ac3ba41 | 316 | "sched-tree", |
5e1607a0 | 317 | "trace_printk", |
b2a866f9 | 318 | "ftrace_preempt", |
9f029e83 | 319 | "branch", |
12ef7d44 | 320 | "annotate", |
02b67518 | 321 | "userstacktrace", |
b54d3de9 | 322 | "sym-userobj", |
66896a85 | 323 | "printk-msg-only", |
c4a8e8be | 324 | "context-info", |
c032ef64 | 325 | "latency-format", |
af4617bd | 326 | "global-clock", |
be6f164a | 327 | "sleep-time", |
a2a16d6a | 328 | "graph-time", |
bc0c38d1 SR |
329 | NULL |
330 | }; | |
331 | ||
4fcdae83 SR |
332 | /* |
333 | * ftrace_max_lock is used to protect the swapping of buffers | |
334 | * when taking a max snapshot. The buffers themselves are | |
335 | * protected by per_cpu spinlocks. But the action of the swap | |
336 | * needs its own lock. | |
337 | * | |
338 | * This is defined as a raw_spinlock_t in order to help | |
339 | * with performance when lockdep debugging is enabled. | |
340 | */ | |
92205c23 SR |
341 | static raw_spinlock_t ftrace_max_lock = |
342 | (raw_spinlock_t)__RAW_SPIN_LOCK_UNLOCKED; | |
bc0c38d1 SR |
343 | |
344 | /* | |
345 | * Copy the new maximum trace into the separate maximum-trace | |
346 | * structure. (this way the maximum trace is permanently saved, | |
347 | * for later retrieval via /debugfs/tracing/latency_trace) | |
348 | */ | |
e309b41d | 349 | static void |
bc0c38d1 SR |
350 | __update_max_tr(struct trace_array *tr, struct task_struct *tsk, int cpu) |
351 | { | |
352 | struct trace_array_cpu *data = tr->data[cpu]; | |
353 | ||
354 | max_tr.cpu = cpu; | |
355 | max_tr.time_start = data->preempt_timestamp; | |
356 | ||
357 | data = max_tr.data[cpu]; | |
358 | data->saved_latency = tracing_max_latency; | |
359 | ||
360 | memcpy(data->comm, tsk->comm, TASK_COMM_LEN); | |
361 | data->pid = tsk->pid; | |
b6dff3ec | 362 | data->uid = task_uid(tsk); |
bc0c38d1 SR |
363 | data->nice = tsk->static_prio - 20 - MAX_RT_PRIO; |
364 | data->policy = tsk->policy; | |
365 | data->rt_priority = tsk->rt_priority; | |
366 | ||
367 | /* record this tasks comm */ | |
af513098 | 368 | tracing_record_cmdline(tsk); |
bc0c38d1 SR |
369 | } |
370 | ||
6c6c2796 PP |
371 | ssize_t trace_seq_to_user(struct trace_seq *s, char __user *ubuf, size_t cnt) |
372 | { | |
373 | int len; | |
374 | int ret; | |
375 | ||
2dc5d12b SR |
376 | if (!cnt) |
377 | return 0; | |
378 | ||
6c6c2796 PP |
379 | if (s->len <= s->readpos) |
380 | return -EBUSY; | |
381 | ||
382 | len = s->len - s->readpos; | |
383 | if (cnt > len) | |
384 | cnt = len; | |
385 | ret = copy_to_user(ubuf, s->buffer + s->readpos, cnt); | |
2dc5d12b | 386 | if (ret == cnt) |
6c6c2796 PP |
387 | return -EFAULT; |
388 | ||
2dc5d12b SR |
389 | cnt -= ret; |
390 | ||
e74da523 | 391 | s->readpos += cnt; |
6c6c2796 | 392 | return cnt; |
214023c3 SR |
393 | } |
394 | ||
b8b94265 | 395 | static ssize_t trace_seq_to_buffer(struct trace_seq *s, void *buf, size_t cnt) |
3c56819b EGM |
396 | { |
397 | int len; | |
398 | void *ret; | |
399 | ||
400 | if (s->len <= s->readpos) | |
401 | return -EBUSY; | |
402 | ||
403 | len = s->len - s->readpos; | |
404 | if (cnt > len) | |
405 | cnt = len; | |
406 | ret = memcpy(buf, s->buffer + s->readpos, cnt); | |
407 | if (!ret) | |
408 | return -EFAULT; | |
409 | ||
e74da523 | 410 | s->readpos += cnt; |
3c56819b EGM |
411 | return cnt; |
412 | } | |
413 | ||
4fcdae83 SR |
414 | /** |
415 | * update_max_tr - snapshot all trace buffers from global_trace to max_tr | |
416 | * @tr: tracer | |
417 | * @tsk: the task with the latency | |
418 | * @cpu: The cpu that initiated the trace. | |
419 | * | |
420 | * Flip the buffers between the @tr and the max_tr and record information | |
421 | * about which task was the cause of this latency. | |
422 | */ | |
e309b41d | 423 | void |
bc0c38d1 SR |
424 | update_max_tr(struct trace_array *tr, struct task_struct *tsk, int cpu) |
425 | { | |
3928a8a2 | 426 | struct ring_buffer *buf = tr->buffer; |
bc0c38d1 | 427 | |
4c11d7ae | 428 | WARN_ON_ONCE(!irqs_disabled()); |
92205c23 | 429 | __raw_spin_lock(&ftrace_max_lock); |
3928a8a2 SR |
430 | |
431 | tr->buffer = max_tr.buffer; | |
432 | max_tr.buffer = buf; | |
433 | ||
d769041f | 434 | ftrace_disable_cpu(); |
3928a8a2 | 435 | ring_buffer_reset(tr->buffer); |
d769041f | 436 | ftrace_enable_cpu(); |
bc0c38d1 SR |
437 | |
438 | __update_max_tr(tr, tsk, cpu); | |
92205c23 | 439 | __raw_spin_unlock(&ftrace_max_lock); |
bc0c38d1 SR |
440 | } |
441 | ||
442 | /** | |
443 | * update_max_tr_single - only copy one trace over, and reset the rest | |
444 | * @tr - tracer | |
445 | * @tsk - task with the latency | |
446 | * @cpu - the cpu of the buffer to copy. | |
4fcdae83 SR |
447 | * |
448 | * Flip the trace of a single CPU buffer between the @tr and the max_tr. | |
bc0c38d1 | 449 | */ |
e309b41d | 450 | void |
bc0c38d1 SR |
451 | update_max_tr_single(struct trace_array *tr, struct task_struct *tsk, int cpu) |
452 | { | |
3928a8a2 | 453 | int ret; |
bc0c38d1 | 454 | |
4c11d7ae | 455 | WARN_ON_ONCE(!irqs_disabled()); |
92205c23 | 456 | __raw_spin_lock(&ftrace_max_lock); |
bc0c38d1 | 457 | |
d769041f SR |
458 | ftrace_disable_cpu(); |
459 | ||
3928a8a2 SR |
460 | ring_buffer_reset(max_tr.buffer); |
461 | ret = ring_buffer_swap_cpu(max_tr.buffer, tr->buffer, cpu); | |
462 | ||
d769041f SR |
463 | ftrace_enable_cpu(); |
464 | ||
97b17efe | 465 | WARN_ON_ONCE(ret && ret != -EAGAIN); |
bc0c38d1 SR |
466 | |
467 | __update_max_tr(tr, tsk, cpu); | |
92205c23 | 468 | __raw_spin_unlock(&ftrace_max_lock); |
bc0c38d1 SR |
469 | } |
470 | ||
4fcdae83 SR |
471 | /** |
472 | * register_tracer - register a tracer with the ftrace system. | |
473 | * @type - the plugin for the tracer | |
474 | * | |
475 | * Register a new plugin tracer. | |
476 | */ | |
bc0c38d1 | 477 | int register_tracer(struct tracer *type) |
e7669b8e HE |
478 | __releases(kernel_lock) |
479 | __acquires(kernel_lock) | |
bc0c38d1 SR |
480 | { |
481 | struct tracer *t; | |
482 | int len; | |
483 | int ret = 0; | |
484 | ||
485 | if (!type->name) { | |
486 | pr_info("Tracer must have a name\n"); | |
487 | return -1; | |
488 | } | |
489 | ||
86fa2f60 IM |
490 | /* |
491 | * When this gets called we hold the BKL which means that | |
492 | * preemption is disabled. Various trace selftests however | |
493 | * need to disable and enable preemption for successful tests. | |
494 | * So we drop the BKL here and grab it after the tests again. | |
495 | */ | |
496 | unlock_kernel(); | |
bc0c38d1 | 497 | mutex_lock(&trace_types_lock); |
86fa2f60 | 498 | |
8e1b82e0 FW |
499 | tracing_selftest_running = true; |
500 | ||
bc0c38d1 SR |
501 | for (t = trace_types; t; t = t->next) { |
502 | if (strcmp(type->name, t->name) == 0) { | |
503 | /* already found */ | |
504 | pr_info("Trace %s already registered\n", | |
505 | type->name); | |
506 | ret = -1; | |
507 | goto out; | |
508 | } | |
509 | } | |
510 | ||
adf9f195 FW |
511 | if (!type->set_flag) |
512 | type->set_flag = &dummy_set_flag; | |
513 | if (!type->flags) | |
514 | type->flags = &dummy_tracer_flags; | |
515 | else | |
516 | if (!type->flags->opts) | |
517 | type->flags->opts = dummy_tracer_opt; | |
6eaaa5d5 FW |
518 | if (!type->wait_pipe) |
519 | type->wait_pipe = default_wait_pipe; | |
520 | ||
adf9f195 | 521 | |
60a11774 | 522 | #ifdef CONFIG_FTRACE_STARTUP_TEST |
b2821ae6 | 523 | if (type->selftest && !tracing_selftest_disabled) { |
60a11774 | 524 | struct tracer *saved_tracer = current_trace; |
60a11774 | 525 | struct trace_array *tr = &global_trace; |
60a11774 | 526 | int i; |
ff32504f | 527 | |
60a11774 SR |
528 | /* |
529 | * Run a selftest on this tracer. | |
530 | * Here we reset the trace buffer, and set the current | |
531 | * tracer to be this tracer. The tracer can then run some | |
532 | * internal tracing to verify that everything is in order. | |
533 | * If we fail, we do not register this tracer. | |
534 | */ | |
86fa2f60 | 535 | for_each_tracing_cpu(i) |
3928a8a2 | 536 | tracing_reset(tr, i); |
86fa2f60 | 537 | |
60a11774 | 538 | current_trace = type; |
60a11774 SR |
539 | /* the test is responsible for initializing and enabling */ |
540 | pr_info("Testing tracer %s: ", type->name); | |
541 | ret = type->selftest(type, tr); | |
542 | /* the test is responsible for resetting too */ | |
543 | current_trace = saved_tracer; | |
60a11774 SR |
544 | if (ret) { |
545 | printk(KERN_CONT "FAILED!\n"); | |
546 | goto out; | |
547 | } | |
1d4db00a | 548 | /* Only reset on passing, to avoid touching corrupted buffers */ |
86fa2f60 | 549 | for_each_tracing_cpu(i) |
3928a8a2 | 550 | tracing_reset(tr, i); |
86fa2f60 | 551 | |
60a11774 SR |
552 | printk(KERN_CONT "PASSED\n"); |
553 | } | |
554 | #endif | |
555 | ||
bc0c38d1 SR |
556 | type->next = trace_types; |
557 | trace_types = type; | |
558 | len = strlen(type->name); | |
559 | if (len > max_tracer_type_len) | |
560 | max_tracer_type_len = len; | |
60a11774 | 561 | |
bc0c38d1 | 562 | out: |
8e1b82e0 | 563 | tracing_selftest_running = false; |
bc0c38d1 SR |
564 | mutex_unlock(&trace_types_lock); |
565 | ||
dac74940 SR |
566 | if (ret || !default_bootup_tracer) |
567 | goto out_unlock; | |
568 | ||
569 | if (strncmp(default_bootup_tracer, type->name, BOOTUP_TRACER_SIZE)) | |
570 | goto out_unlock; | |
571 | ||
572 | printk(KERN_INFO "Starting tracer '%s'\n", type->name); | |
573 | /* Do we want this tracer to start on bootup? */ | |
574 | tracing_set_tracer(type->name); | |
575 | default_bootup_tracer = NULL; | |
576 | /* disable other selftests, since this will break it. */ | |
577 | tracing_selftest_disabled = 1; | |
b2821ae6 | 578 | #ifdef CONFIG_FTRACE_STARTUP_TEST |
dac74940 SR |
579 | printk(KERN_INFO "Disabling FTRACE selftests due to running tracer '%s'\n", |
580 | type->name); | |
b2821ae6 | 581 | #endif |
b2821ae6 | 582 | |
dac74940 | 583 | out_unlock: |
b2821ae6 | 584 | lock_kernel(); |
bc0c38d1 SR |
585 | return ret; |
586 | } | |
587 | ||
588 | void unregister_tracer(struct tracer *type) | |
589 | { | |
590 | struct tracer **t; | |
591 | int len; | |
592 | ||
593 | mutex_lock(&trace_types_lock); | |
594 | for (t = &trace_types; *t; t = &(*t)->next) { | |
595 | if (*t == type) | |
596 | goto found; | |
597 | } | |
598 | pr_info("Trace %s not registered\n", type->name); | |
599 | goto out; | |
600 | ||
601 | found: | |
602 | *t = (*t)->next; | |
b5db03c4 ACM |
603 | |
604 | if (type == current_trace && tracer_enabled) { | |
605 | tracer_enabled = 0; | |
606 | tracing_stop(); | |
607 | if (current_trace->stop) | |
608 | current_trace->stop(&global_trace); | |
609 | current_trace = &nop_trace; | |
610 | } | |
611 | ||
bc0c38d1 SR |
612 | if (strlen(type->name) != max_tracer_type_len) |
613 | goto out; | |
614 | ||
615 | max_tracer_type_len = 0; | |
616 | for (t = &trace_types; *t; t = &(*t)->next) { | |
617 | len = strlen((*t)->name); | |
618 | if (len > max_tracer_type_len) | |
619 | max_tracer_type_len = len; | |
620 | } | |
621 | out: | |
622 | mutex_unlock(&trace_types_lock); | |
623 | } | |
624 | ||
3928a8a2 | 625 | void tracing_reset(struct trace_array *tr, int cpu) |
bc0c38d1 | 626 | { |
d769041f | 627 | ftrace_disable_cpu(); |
3928a8a2 | 628 | ring_buffer_reset_cpu(tr->buffer, cpu); |
d769041f | 629 | ftrace_enable_cpu(); |
bc0c38d1 SR |
630 | } |
631 | ||
213cc060 PE |
632 | void tracing_reset_online_cpus(struct trace_array *tr) |
633 | { | |
634 | int cpu; | |
635 | ||
636 | tr->time_start = ftrace_now(tr->cpu); | |
637 | ||
638 | for_each_online_cpu(cpu) | |
639 | tracing_reset(tr, cpu); | |
640 | } | |
641 | ||
9456f0fa SR |
642 | void tracing_reset_current(int cpu) |
643 | { | |
644 | tracing_reset(&global_trace, cpu); | |
645 | } | |
646 | ||
647 | void tracing_reset_current_online_cpus(void) | |
648 | { | |
649 | tracing_reset_online_cpus(&global_trace); | |
650 | } | |
651 | ||
bc0c38d1 | 652 | #define SAVED_CMDLINES 128 |
2c7eea4c | 653 | #define NO_CMDLINE_MAP UINT_MAX |
bc0c38d1 SR |
654 | static unsigned map_pid_to_cmdline[PID_MAX_DEFAULT+1]; |
655 | static unsigned map_cmdline_to_pid[SAVED_CMDLINES]; | |
656 | static char saved_cmdlines[SAVED_CMDLINES][TASK_COMM_LEN]; | |
657 | static int cmdline_idx; | |
efed792d | 658 | static raw_spinlock_t trace_cmdline_lock = __RAW_SPIN_LOCK_UNLOCKED; |
25b0b44a | 659 | |
25b0b44a | 660 | /* temporary disable recording */ |
4fd27358 | 661 | static atomic_t trace_record_cmdline_disabled __read_mostly; |
bc0c38d1 SR |
662 | |
663 | static void trace_init_cmdlines(void) | |
664 | { | |
2c7eea4c TG |
665 | memset(&map_pid_to_cmdline, NO_CMDLINE_MAP, sizeof(map_pid_to_cmdline)); |
666 | memset(&map_cmdline_to_pid, NO_CMDLINE_MAP, sizeof(map_cmdline_to_pid)); | |
bc0c38d1 SR |
667 | cmdline_idx = 0; |
668 | } | |
669 | ||
0f048701 SR |
670 | static int trace_stop_count; |
671 | static DEFINE_SPINLOCK(tracing_start_lock); | |
672 | ||
69bb54ec SR |
673 | /** |
674 | * ftrace_off_permanent - disable all ftrace code permanently | |
675 | * | |
676 | * This should only be called when a serious anomally has | |
677 | * been detected. This will turn off the function tracing, | |
678 | * ring buffers, and other tracing utilites. It takes no | |
679 | * locks and can be called from any context. | |
680 | */ | |
681 | void ftrace_off_permanent(void) | |
682 | { | |
683 | tracing_disabled = 1; | |
684 | ftrace_stop(); | |
685 | tracing_off_permanent(); | |
686 | } | |
687 | ||
0f048701 SR |
688 | /** |
689 | * tracing_start - quick start of the tracer | |
690 | * | |
691 | * If tracing is enabled but was stopped by tracing_stop, | |
692 | * this will start the tracer back up. | |
693 | */ | |
694 | void tracing_start(void) | |
695 | { | |
696 | struct ring_buffer *buffer; | |
697 | unsigned long flags; | |
698 | ||
699 | if (tracing_disabled) | |
700 | return; | |
701 | ||
702 | spin_lock_irqsave(&tracing_start_lock, flags); | |
b06a8301 SR |
703 | if (--trace_stop_count) { |
704 | if (trace_stop_count < 0) { | |
705 | /* Someone screwed up their debugging */ | |
706 | WARN_ON_ONCE(1); | |
707 | trace_stop_count = 0; | |
708 | } | |
0f048701 SR |
709 | goto out; |
710 | } | |
711 | ||
712 | ||
713 | buffer = global_trace.buffer; | |
714 | if (buffer) | |
715 | ring_buffer_record_enable(buffer); | |
716 | ||
717 | buffer = max_tr.buffer; | |
718 | if (buffer) | |
719 | ring_buffer_record_enable(buffer); | |
720 | ||
721 | ftrace_start(); | |
722 | out: | |
723 | spin_unlock_irqrestore(&tracing_start_lock, flags); | |
724 | } | |
725 | ||
726 | /** | |
727 | * tracing_stop - quick stop of the tracer | |
728 | * | |
729 | * Light weight way to stop tracing. Use in conjunction with | |
730 | * tracing_start. | |
731 | */ | |
732 | void tracing_stop(void) | |
733 | { | |
734 | struct ring_buffer *buffer; | |
735 | unsigned long flags; | |
736 | ||
737 | ftrace_stop(); | |
738 | spin_lock_irqsave(&tracing_start_lock, flags); | |
739 | if (trace_stop_count++) | |
740 | goto out; | |
741 | ||
742 | buffer = global_trace.buffer; | |
743 | if (buffer) | |
744 | ring_buffer_record_disable(buffer); | |
745 | ||
746 | buffer = max_tr.buffer; | |
747 | if (buffer) | |
748 | ring_buffer_record_disable(buffer); | |
749 | ||
750 | out: | |
751 | spin_unlock_irqrestore(&tracing_start_lock, flags); | |
752 | } | |
753 | ||
e309b41d | 754 | void trace_stop_cmdline_recording(void); |
bc0c38d1 | 755 | |
e309b41d | 756 | static void trace_save_cmdline(struct task_struct *tsk) |
bc0c38d1 | 757 | { |
a635cf04 | 758 | unsigned pid, idx; |
bc0c38d1 SR |
759 | |
760 | if (!tsk->pid || unlikely(tsk->pid > PID_MAX_DEFAULT)) | |
761 | return; | |
762 | ||
763 | /* | |
764 | * It's not the end of the world if we don't get | |
765 | * the lock, but we also don't want to spin | |
766 | * nor do we want to disable interrupts, | |
767 | * so if we miss here, then better luck next time. | |
768 | */ | |
efed792d | 769 | if (!__raw_spin_trylock(&trace_cmdline_lock)) |
bc0c38d1 SR |
770 | return; |
771 | ||
772 | idx = map_pid_to_cmdline[tsk->pid]; | |
2c7eea4c | 773 | if (idx == NO_CMDLINE_MAP) { |
bc0c38d1 SR |
774 | idx = (cmdline_idx + 1) % SAVED_CMDLINES; |
775 | ||
a635cf04 CE |
776 | /* |
777 | * Check whether the cmdline buffer at idx has a pid | |
778 | * mapped. We are going to overwrite that entry so we | |
779 | * need to clear the map_pid_to_cmdline. Otherwise we | |
780 | * would read the new comm for the old pid. | |
781 | */ | |
782 | pid = map_cmdline_to_pid[idx]; | |
783 | if (pid != NO_CMDLINE_MAP) | |
784 | map_pid_to_cmdline[pid] = NO_CMDLINE_MAP; | |
bc0c38d1 | 785 | |
a635cf04 | 786 | map_cmdline_to_pid[idx] = tsk->pid; |
bc0c38d1 SR |
787 | map_pid_to_cmdline[tsk->pid] = idx; |
788 | ||
789 | cmdline_idx = idx; | |
790 | } | |
791 | ||
792 | memcpy(&saved_cmdlines[idx], tsk->comm, TASK_COMM_LEN); | |
793 | ||
efed792d | 794 | __raw_spin_unlock(&trace_cmdline_lock); |
bc0c38d1 SR |
795 | } |
796 | ||
4ca53085 | 797 | void trace_find_cmdline(int pid, char comm[]) |
bc0c38d1 | 798 | { |
bc0c38d1 SR |
799 | unsigned map; |
800 | ||
4ca53085 SR |
801 | if (!pid) { |
802 | strcpy(comm, "<idle>"); | |
803 | return; | |
804 | } | |
bc0c38d1 | 805 | |
4ca53085 SR |
806 | if (pid > PID_MAX_DEFAULT) { |
807 | strcpy(comm, "<...>"); | |
808 | return; | |
809 | } | |
bc0c38d1 | 810 | |
4ca53085 | 811 | __raw_spin_lock(&trace_cmdline_lock); |
bc0c38d1 | 812 | map = map_pid_to_cmdline[pid]; |
50d88758 TG |
813 | if (map != NO_CMDLINE_MAP) |
814 | strcpy(comm, saved_cmdlines[map]); | |
815 | else | |
816 | strcpy(comm, "<...>"); | |
bc0c38d1 | 817 | |
4ca53085 | 818 | __raw_spin_unlock(&trace_cmdline_lock); |
bc0c38d1 SR |
819 | } |
820 | ||
e309b41d | 821 | void tracing_record_cmdline(struct task_struct *tsk) |
bc0c38d1 | 822 | { |
18aecd36 TG |
823 | if (atomic_read(&trace_record_cmdline_disabled) || !tracer_enabled || |
824 | !tracing_is_on()) | |
bc0c38d1 SR |
825 | return; |
826 | ||
827 | trace_save_cmdline(tsk); | |
828 | } | |
829 | ||
45dcd8b8 | 830 | void |
38697053 SR |
831 | tracing_generic_entry_update(struct trace_entry *entry, unsigned long flags, |
832 | int pc) | |
bc0c38d1 SR |
833 | { |
834 | struct task_struct *tsk = current; | |
bc0c38d1 | 835 | |
777e208d SR |
836 | entry->preempt_count = pc & 0xff; |
837 | entry->pid = (tsk) ? tsk->pid : 0; | |
ef18012b | 838 | entry->tgid = (tsk) ? tsk->tgid : 0; |
777e208d | 839 | entry->flags = |
9244489a | 840 | #ifdef CONFIG_TRACE_IRQFLAGS_SUPPORT |
2e2ca155 | 841 | (irqs_disabled_flags(flags) ? TRACE_FLAG_IRQS_OFF : 0) | |
9244489a SR |
842 | #else |
843 | TRACE_FLAG_IRQS_NOSUPPORT | | |
844 | #endif | |
bc0c38d1 SR |
845 | ((pc & HARDIRQ_MASK) ? TRACE_FLAG_HARDIRQ : 0) | |
846 | ((pc & SOFTIRQ_MASK) ? TRACE_FLAG_SOFTIRQ : 0) | | |
847 | (need_resched() ? TRACE_FLAG_NEED_RESCHED : 0); | |
848 | } | |
849 | ||
51a763dd | 850 | struct ring_buffer_event *trace_buffer_lock_reserve(struct trace_array *tr, |
7a4f453b | 851 | int type, |
51a763dd ACM |
852 | unsigned long len, |
853 | unsigned long flags, int pc) | |
854 | { | |
855 | struct ring_buffer_event *event; | |
856 | ||
857 | event = ring_buffer_lock_reserve(tr->buffer, len); | |
858 | if (event != NULL) { | |
859 | struct trace_entry *ent = ring_buffer_event_data(event); | |
860 | ||
861 | tracing_generic_entry_update(ent, flags, pc); | |
862 | ent->type = type; | |
863 | } | |
864 | ||
865 | return event; | |
866 | } | |
867 | static void ftrace_trace_stack(struct trace_array *tr, | |
868 | unsigned long flags, int skip, int pc); | |
869 | static void ftrace_trace_userstack(struct trace_array *tr, | |
870 | unsigned long flags, int pc); | |
871 | ||
07edf712 FW |
872 | static inline void __trace_buffer_unlock_commit(struct trace_array *tr, |
873 | struct ring_buffer_event *event, | |
874 | unsigned long flags, int pc, | |
875 | int wake) | |
51a763dd ACM |
876 | { |
877 | ring_buffer_unlock_commit(tr->buffer, event); | |
878 | ||
879 | ftrace_trace_stack(tr, flags, 6, pc); | |
880 | ftrace_trace_userstack(tr, flags, pc); | |
07edf712 FW |
881 | |
882 | if (wake) | |
883 | trace_wake_up(); | |
884 | } | |
885 | ||
886 | void trace_buffer_unlock_commit(struct trace_array *tr, | |
887 | struct ring_buffer_event *event, | |
888 | unsigned long flags, int pc) | |
889 | { | |
890 | __trace_buffer_unlock_commit(tr, event, flags, pc, 1); | |
51a763dd ACM |
891 | } |
892 | ||
ef5580d0 | 893 | struct ring_buffer_event * |
7a4f453b | 894 | trace_current_buffer_lock_reserve(int type, unsigned long len, |
ef5580d0 SR |
895 | unsigned long flags, int pc) |
896 | { | |
897 | return trace_buffer_lock_reserve(&global_trace, | |
898 | type, len, flags, pc); | |
899 | } | |
94487d6d | 900 | EXPORT_SYMBOL_GPL(trace_current_buffer_lock_reserve); |
ef5580d0 SR |
901 | |
902 | void trace_current_buffer_unlock_commit(struct ring_buffer_event *event, | |
903 | unsigned long flags, int pc) | |
904 | { | |
77d9f465 | 905 | __trace_buffer_unlock_commit(&global_trace, event, flags, pc, 1); |
07edf712 | 906 | } |
94487d6d | 907 | EXPORT_SYMBOL_GPL(trace_current_buffer_unlock_commit); |
07edf712 FW |
908 | |
909 | void trace_nowake_buffer_unlock_commit(struct ring_buffer_event *event, | |
910 | unsigned long flags, int pc) | |
911 | { | |
77d9f465 SR |
912 | __trace_buffer_unlock_commit(&global_trace, event, flags, pc, 0); |
913 | } | |
94487d6d | 914 | EXPORT_SYMBOL_GPL(trace_nowake_buffer_unlock_commit); |
77d9f465 SR |
915 | |
916 | void trace_current_buffer_discard_commit(struct ring_buffer_event *event) | |
917 | { | |
918 | ring_buffer_discard_commit(global_trace.buffer, event); | |
ef5580d0 | 919 | } |
12acd473 | 920 | EXPORT_SYMBOL_GPL(trace_current_buffer_discard_commit); |
ef5580d0 | 921 | |
e309b41d | 922 | void |
7be42151 | 923 | trace_function(struct trace_array *tr, |
38697053 SR |
924 | unsigned long ip, unsigned long parent_ip, unsigned long flags, |
925 | int pc) | |
bc0c38d1 | 926 | { |
e1112b4d | 927 | struct ftrace_event_call *call = &event_function; |
3928a8a2 | 928 | struct ring_buffer_event *event; |
777e208d | 929 | struct ftrace_entry *entry; |
bc0c38d1 | 930 | |
d769041f SR |
931 | /* If we are reading the ring buffer, don't trace */ |
932 | if (unlikely(local_read(&__get_cpu_var(ftrace_cpu_disabled)))) | |
933 | return; | |
934 | ||
51a763dd ACM |
935 | event = trace_buffer_lock_reserve(tr, TRACE_FN, sizeof(*entry), |
936 | flags, pc); | |
3928a8a2 SR |
937 | if (!event) |
938 | return; | |
939 | entry = ring_buffer_event_data(event); | |
777e208d SR |
940 | entry->ip = ip; |
941 | entry->parent_ip = parent_ip; | |
e1112b4d | 942 | |
eb02ce01 TZ |
943 | if (!filter_check_discard(call, entry, tr->buffer, event)) |
944 | ring_buffer_unlock_commit(tr->buffer, event); | |
bc0c38d1 SR |
945 | } |
946 | ||
fb52607a | 947 | #ifdef CONFIG_FUNCTION_GRAPH_TRACER |
16185369 | 948 | static int __trace_graph_entry(struct trace_array *tr, |
287b6e68 FW |
949 | struct ftrace_graph_ent *trace, |
950 | unsigned long flags, | |
951 | int pc) | |
952 | { | |
e1112b4d | 953 | struct ftrace_event_call *call = &event_funcgraph_entry; |
287b6e68 FW |
954 | struct ring_buffer_event *event; |
955 | struct ftrace_graph_ent_entry *entry; | |
287b6e68 FW |
956 | |
957 | if (unlikely(local_read(&__get_cpu_var(ftrace_cpu_disabled)))) | |
16185369 | 958 | return 0; |
287b6e68 | 959 | |
51a763dd ACM |
960 | event = trace_buffer_lock_reserve(&global_trace, TRACE_GRAPH_ENT, |
961 | sizeof(*entry), flags, pc); | |
287b6e68 | 962 | if (!event) |
16185369 | 963 | return 0; |
287b6e68 | 964 | entry = ring_buffer_event_data(event); |
287b6e68 | 965 | entry->graph_ent = *trace; |
eb02ce01 TZ |
966 | if (!filter_current_check_discard(call, entry, event)) |
967 | ring_buffer_unlock_commit(global_trace.buffer, event); | |
16185369 FW |
968 | |
969 | return 1; | |
287b6e68 FW |
970 | } |
971 | ||
972 | static void __trace_graph_return(struct trace_array *tr, | |
fb52607a | 973 | struct ftrace_graph_ret *trace, |
15e6cb36 FW |
974 | unsigned long flags, |
975 | int pc) | |
976 | { | |
e1112b4d | 977 | struct ftrace_event_call *call = &event_funcgraph_exit; |
15e6cb36 | 978 | struct ring_buffer_event *event; |
287b6e68 | 979 | struct ftrace_graph_ret_entry *entry; |
15e6cb36 FW |
980 | |
981 | if (unlikely(local_read(&__get_cpu_var(ftrace_cpu_disabled)))) | |
982 | return; | |
983 | ||
51a763dd ACM |
984 | event = trace_buffer_lock_reserve(&global_trace, TRACE_GRAPH_RET, |
985 | sizeof(*entry), flags, pc); | |
15e6cb36 FW |
986 | if (!event) |
987 | return; | |
988 | entry = ring_buffer_event_data(event); | |
287b6e68 | 989 | entry->ret = *trace; |
eb02ce01 TZ |
990 | if (!filter_current_check_discard(call, entry, event)) |
991 | ring_buffer_unlock_commit(global_trace.buffer, event); | |
15e6cb36 FW |
992 | } |
993 | #endif | |
994 | ||
e309b41d | 995 | void |
2e0f5761 | 996 | ftrace(struct trace_array *tr, struct trace_array_cpu *data, |
38697053 SR |
997 | unsigned long ip, unsigned long parent_ip, unsigned long flags, |
998 | int pc) | |
2e0f5761 IM |
999 | { |
1000 | if (likely(!atomic_read(&data->disabled))) | |
7be42151 | 1001 | trace_function(tr, ip, parent_ip, flags, pc); |
2e0f5761 IM |
1002 | } |
1003 | ||
53614991 | 1004 | static void __ftrace_trace_stack(struct trace_array *tr, |
53614991 SR |
1005 | unsigned long flags, |
1006 | int skip, int pc) | |
86387f7e | 1007 | { |
c2c80529 | 1008 | #ifdef CONFIG_STACKTRACE |
e1112b4d | 1009 | struct ftrace_event_call *call = &event_kernel_stack; |
3928a8a2 | 1010 | struct ring_buffer_event *event; |
777e208d | 1011 | struct stack_entry *entry; |
86387f7e IM |
1012 | struct stack_trace trace; |
1013 | ||
51a763dd ACM |
1014 | event = trace_buffer_lock_reserve(tr, TRACE_STACK, |
1015 | sizeof(*entry), flags, pc); | |
3928a8a2 SR |
1016 | if (!event) |
1017 | return; | |
1018 | entry = ring_buffer_event_data(event); | |
777e208d | 1019 | memset(&entry->caller, 0, sizeof(entry->caller)); |
86387f7e IM |
1020 | |
1021 | trace.nr_entries = 0; | |
1022 | trace.max_entries = FTRACE_STACK_ENTRIES; | |
1023 | trace.skip = skip; | |
777e208d | 1024 | trace.entries = entry->caller; |
86387f7e IM |
1025 | |
1026 | save_stack_trace(&trace); | |
eb02ce01 TZ |
1027 | if (!filter_check_discard(call, entry, tr->buffer, event)) |
1028 | ring_buffer_unlock_commit(tr->buffer, event); | |
c2c80529 | 1029 | #endif |
f0a920d5 IM |
1030 | } |
1031 | ||
53614991 | 1032 | static void ftrace_trace_stack(struct trace_array *tr, |
53614991 SR |
1033 | unsigned long flags, |
1034 | int skip, int pc) | |
1035 | { | |
1036 | if (!(trace_flags & TRACE_ITER_STACKTRACE)) | |
1037 | return; | |
1038 | ||
7be42151 | 1039 | __ftrace_trace_stack(tr, flags, skip, pc); |
53614991 SR |
1040 | } |
1041 | ||
38697053 | 1042 | void __trace_stack(struct trace_array *tr, |
38697053 | 1043 | unsigned long flags, |
53614991 | 1044 | int skip, int pc) |
38697053 | 1045 | { |
7be42151 | 1046 | __ftrace_trace_stack(tr, flags, skip, pc); |
38697053 SR |
1047 | } |
1048 | ||
02b67518 | 1049 | static void ftrace_trace_userstack(struct trace_array *tr, |
7be42151 | 1050 | unsigned long flags, int pc) |
02b67518 | 1051 | { |
c7425acb | 1052 | #ifdef CONFIG_STACKTRACE |
e1112b4d | 1053 | struct ftrace_event_call *call = &event_user_stack; |
8d7c6a96 | 1054 | struct ring_buffer_event *event; |
02b67518 TE |
1055 | struct userstack_entry *entry; |
1056 | struct stack_trace trace; | |
02b67518 TE |
1057 | |
1058 | if (!(trace_flags & TRACE_ITER_USERSTACKTRACE)) | |
1059 | return; | |
1060 | ||
51a763dd ACM |
1061 | event = trace_buffer_lock_reserve(tr, TRACE_USER_STACK, |
1062 | sizeof(*entry), flags, pc); | |
02b67518 TE |
1063 | if (!event) |
1064 | return; | |
1065 | entry = ring_buffer_event_data(event); | |
02b67518 TE |
1066 | |
1067 | memset(&entry->caller, 0, sizeof(entry->caller)); | |
1068 | ||
1069 | trace.nr_entries = 0; | |
1070 | trace.max_entries = FTRACE_STACK_ENTRIES; | |
1071 | trace.skip = 0; | |
1072 | trace.entries = entry->caller; | |
1073 | ||
1074 | save_stack_trace_user(&trace); | |
eb02ce01 TZ |
1075 | if (!filter_check_discard(call, entry, tr->buffer, event)) |
1076 | ring_buffer_unlock_commit(tr->buffer, event); | |
c7425acb | 1077 | #endif |
02b67518 TE |
1078 | } |
1079 | ||
4fd27358 HE |
1080 | #ifdef UNUSED |
1081 | static void __trace_userstack(struct trace_array *tr, unsigned long flags) | |
02b67518 | 1082 | { |
7be42151 | 1083 | ftrace_trace_userstack(tr, flags, preempt_count()); |
02b67518 | 1084 | } |
4fd27358 | 1085 | #endif /* UNUSED */ |
02b67518 | 1086 | |
38697053 | 1087 | static void |
7be42151 | 1088 | ftrace_trace_special(void *__tr, |
38697053 SR |
1089 | unsigned long arg1, unsigned long arg2, unsigned long arg3, |
1090 | int pc) | |
a4feb834 | 1091 | { |
3928a8a2 | 1092 | struct ring_buffer_event *event; |
a4feb834 | 1093 | struct trace_array *tr = __tr; |
777e208d | 1094 | struct special_entry *entry; |
a4feb834 | 1095 | |
51a763dd ACM |
1096 | event = trace_buffer_lock_reserve(tr, TRACE_SPECIAL, |
1097 | sizeof(*entry), 0, pc); | |
3928a8a2 SR |
1098 | if (!event) |
1099 | return; | |
1100 | entry = ring_buffer_event_data(event); | |
777e208d SR |
1101 | entry->arg1 = arg1; |
1102 | entry->arg2 = arg2; | |
1103 | entry->arg3 = arg3; | |
51a763dd | 1104 | trace_buffer_unlock_commit(tr, event, 0, pc); |
a4feb834 IM |
1105 | } |
1106 | ||
38697053 SR |
1107 | void |
1108 | __trace_special(void *__tr, void *__data, | |
1109 | unsigned long arg1, unsigned long arg2, unsigned long arg3) | |
1110 | { | |
7be42151 | 1111 | ftrace_trace_special(__tr, arg1, arg2, arg3, preempt_count()); |
38697053 SR |
1112 | } |
1113 | ||
e309b41d | 1114 | void |
bc0c38d1 | 1115 | tracing_sched_switch_trace(struct trace_array *tr, |
86387f7e IM |
1116 | struct task_struct *prev, |
1117 | struct task_struct *next, | |
38697053 | 1118 | unsigned long flags, int pc) |
bc0c38d1 | 1119 | { |
e1112b4d | 1120 | struct ftrace_event_call *call = &event_context_switch; |
3928a8a2 | 1121 | struct ring_buffer_event *event; |
777e208d | 1122 | struct ctx_switch_entry *entry; |
bc0c38d1 | 1123 | |
51a763dd ACM |
1124 | event = trace_buffer_lock_reserve(tr, TRACE_CTX, |
1125 | sizeof(*entry), flags, pc); | |
3928a8a2 SR |
1126 | if (!event) |
1127 | return; | |
1128 | entry = ring_buffer_event_data(event); | |
777e208d SR |
1129 | entry->prev_pid = prev->pid; |
1130 | entry->prev_prio = prev->prio; | |
1131 | entry->prev_state = prev->state; | |
1132 | entry->next_pid = next->pid; | |
1133 | entry->next_prio = next->prio; | |
1134 | entry->next_state = next->state; | |
1135 | entry->next_cpu = task_cpu(next); | |
e1112b4d | 1136 | |
eb02ce01 TZ |
1137 | if (!filter_check_discard(call, entry, tr->buffer, event)) |
1138 | trace_buffer_unlock_commit(tr, event, flags, pc); | |
bc0c38d1 SR |
1139 | } |
1140 | ||
57422797 IM |
1141 | void |
1142 | tracing_sched_wakeup_trace(struct trace_array *tr, | |
86387f7e IM |
1143 | struct task_struct *wakee, |
1144 | struct task_struct *curr, | |
38697053 | 1145 | unsigned long flags, int pc) |
57422797 | 1146 | { |
e1112b4d | 1147 | struct ftrace_event_call *call = &event_wakeup; |
3928a8a2 | 1148 | struct ring_buffer_event *event; |
777e208d | 1149 | struct ctx_switch_entry *entry; |
57422797 | 1150 | |
51a763dd ACM |
1151 | event = trace_buffer_lock_reserve(tr, TRACE_WAKE, |
1152 | sizeof(*entry), flags, pc); | |
3928a8a2 SR |
1153 | if (!event) |
1154 | return; | |
1155 | entry = ring_buffer_event_data(event); | |
777e208d SR |
1156 | entry->prev_pid = curr->pid; |
1157 | entry->prev_prio = curr->prio; | |
1158 | entry->prev_state = curr->state; | |
1159 | entry->next_pid = wakee->pid; | |
1160 | entry->next_prio = wakee->prio; | |
1161 | entry->next_state = wakee->state; | |
1162 | entry->next_cpu = task_cpu(wakee); | |
6eaaa5d5 | 1163 | |
eb02ce01 TZ |
1164 | if (!filter_check_discard(call, entry, tr->buffer, event)) |
1165 | ring_buffer_unlock_commit(tr->buffer, event); | |
6eaaa5d5 FW |
1166 | ftrace_trace_stack(tr, flags, 6, pc); |
1167 | ftrace_trace_userstack(tr, flags, pc); | |
57422797 IM |
1168 | } |
1169 | ||
4902f884 SR |
1170 | void |
1171 | ftrace_special(unsigned long arg1, unsigned long arg2, unsigned long arg3) | |
1172 | { | |
1173 | struct trace_array *tr = &global_trace; | |
1174 | struct trace_array_cpu *data; | |
5aa1ba6a | 1175 | unsigned long flags; |
4902f884 | 1176 | int cpu; |
38697053 | 1177 | int pc; |
4902f884 | 1178 | |
c76f0694 | 1179 | if (tracing_disabled) |
4902f884 SR |
1180 | return; |
1181 | ||
38697053 | 1182 | pc = preempt_count(); |
5aa1ba6a | 1183 | local_irq_save(flags); |
4902f884 SR |
1184 | cpu = raw_smp_processor_id(); |
1185 | data = tr->data[cpu]; | |
4902f884 | 1186 | |
5aa1ba6a | 1187 | if (likely(atomic_inc_return(&data->disabled) == 1)) |
7be42151 | 1188 | ftrace_trace_special(tr, arg1, arg2, arg3, pc); |
4902f884 | 1189 | |
5aa1ba6a SR |
1190 | atomic_dec(&data->disabled); |
1191 | local_irq_restore(flags); | |
4902f884 SR |
1192 | } |
1193 | ||
fb52607a | 1194 | #ifdef CONFIG_FUNCTION_GRAPH_TRACER |
e49dc19c | 1195 | int trace_graph_entry(struct ftrace_graph_ent *trace) |
15e6cb36 FW |
1196 | { |
1197 | struct trace_array *tr = &global_trace; | |
1198 | struct trace_array_cpu *data; | |
1199 | unsigned long flags; | |
1200 | long disabled; | |
16185369 | 1201 | int ret; |
15e6cb36 FW |
1202 | int cpu; |
1203 | int pc; | |
1204 | ||
804a6851 SR |
1205 | if (!ftrace_trace_task(current)) |
1206 | return 0; | |
1207 | ||
ea4e2bc4 SR |
1208 | if (!ftrace_graph_addr(trace->func)) |
1209 | return 0; | |
1210 | ||
a5e25883 | 1211 | local_irq_save(flags); |
15e6cb36 FW |
1212 | cpu = raw_smp_processor_id(); |
1213 | data = tr->data[cpu]; | |
1214 | disabled = atomic_inc_return(&data->disabled); | |
1215 | if (likely(disabled == 1)) { | |
1216 | pc = preempt_count(); | |
16185369 FW |
1217 | ret = __trace_graph_entry(tr, trace, flags, pc); |
1218 | } else { | |
1219 | ret = 0; | |
287b6e68 | 1220 | } |
ea4e2bc4 SR |
1221 | /* Only do the atomic if it is not already set */ |
1222 | if (!test_tsk_trace_graph(current)) | |
1223 | set_tsk_trace_graph(current); | |
16185369 | 1224 | |
287b6e68 | 1225 | atomic_dec(&data->disabled); |
a5e25883 | 1226 | local_irq_restore(flags); |
e49dc19c | 1227 | |
16185369 | 1228 | return ret; |
287b6e68 FW |
1229 | } |
1230 | ||
1231 | void trace_graph_return(struct ftrace_graph_ret *trace) | |
1232 | { | |
1233 | struct trace_array *tr = &global_trace; | |
1234 | struct trace_array_cpu *data; | |
1235 | unsigned long flags; | |
1236 | long disabled; | |
1237 | int cpu; | |
1238 | int pc; | |
1239 | ||
a5e25883 | 1240 | local_irq_save(flags); |
287b6e68 FW |
1241 | cpu = raw_smp_processor_id(); |
1242 | data = tr->data[cpu]; | |
1243 | disabled = atomic_inc_return(&data->disabled); | |
1244 | if (likely(disabled == 1)) { | |
1245 | pc = preempt_count(); | |
7be42151 | 1246 | __trace_graph_return(tr, trace, flags, pc); |
15e6cb36 | 1247 | } |
ea4e2bc4 SR |
1248 | if (!trace->depth) |
1249 | clear_tsk_trace_graph(current); | |
15e6cb36 | 1250 | atomic_dec(&data->disabled); |
a5e25883 | 1251 | local_irq_restore(flags); |
15e6cb36 | 1252 | } |
fb52607a | 1253 | #endif /* CONFIG_FUNCTION_GRAPH_TRACER */ |
15e6cb36 | 1254 | |
769b0441 FW |
1255 | |
1256 | /** | |
48ead020 | 1257 | * trace_vbprintk - write binary msg to tracing buffer |
769b0441 FW |
1258 | * |
1259 | */ | |
40ce74f1 | 1260 | int trace_vbprintk(unsigned long ip, const char *fmt, va_list args) |
769b0441 | 1261 | { |
80370cb7 SR |
1262 | static raw_spinlock_t trace_buf_lock = |
1263 | (raw_spinlock_t)__RAW_SPIN_LOCK_UNLOCKED; | |
769b0441 FW |
1264 | static u32 trace_buf[TRACE_BUF_SIZE]; |
1265 | ||
e1112b4d | 1266 | struct ftrace_event_call *call = &event_bprint; |
769b0441 FW |
1267 | struct ring_buffer_event *event; |
1268 | struct trace_array *tr = &global_trace; | |
1269 | struct trace_array_cpu *data; | |
48ead020 | 1270 | struct bprint_entry *entry; |
769b0441 | 1271 | unsigned long flags; |
3189cdb3 | 1272 | int disable; |
769b0441 FW |
1273 | int resched; |
1274 | int cpu, len = 0, size, pc; | |
1275 | ||
1276 | if (unlikely(tracing_selftest_running || tracing_disabled)) | |
1277 | return 0; | |
1278 | ||
1279 | /* Don't pollute graph traces with trace_vprintk internals */ | |
1280 | pause_graph_tracing(); | |
1281 | ||
1282 | pc = preempt_count(); | |
1283 | resched = ftrace_preempt_disable(); | |
1284 | cpu = raw_smp_processor_id(); | |
1285 | data = tr->data[cpu]; | |
1286 | ||
3189cdb3 SR |
1287 | disable = atomic_inc_return(&data->disabled); |
1288 | if (unlikely(disable != 1)) | |
769b0441 FW |
1289 | goto out; |
1290 | ||
80370cb7 SR |
1291 | /* Lockdep uses trace_printk for lock tracing */ |
1292 | local_irq_save(flags); | |
1293 | __raw_spin_lock(&trace_buf_lock); | |
769b0441 FW |
1294 | len = vbin_printf(trace_buf, TRACE_BUF_SIZE, fmt, args); |
1295 | ||
1296 | if (len > TRACE_BUF_SIZE || len < 0) | |
1297 | goto out_unlock; | |
1298 | ||
1299 | size = sizeof(*entry) + sizeof(u32) * len; | |
48ead020 | 1300 | event = trace_buffer_lock_reserve(tr, TRACE_BPRINT, size, flags, pc); |
769b0441 FW |
1301 | if (!event) |
1302 | goto out_unlock; | |
1303 | entry = ring_buffer_event_data(event); | |
1304 | entry->ip = ip; | |
769b0441 FW |
1305 | entry->fmt = fmt; |
1306 | ||
1307 | memcpy(entry->buf, trace_buf, sizeof(u32) * len); | |
eb02ce01 TZ |
1308 | if (!filter_check_discard(call, entry, tr->buffer, event)) |
1309 | ring_buffer_unlock_commit(tr->buffer, event); | |
769b0441 FW |
1310 | |
1311 | out_unlock: | |
80370cb7 SR |
1312 | __raw_spin_unlock(&trace_buf_lock); |
1313 | local_irq_restore(flags); | |
769b0441 FW |
1314 | |
1315 | out: | |
3189cdb3 | 1316 | atomic_dec_return(&data->disabled); |
769b0441 FW |
1317 | ftrace_preempt_enable(resched); |
1318 | unpause_graph_tracing(); | |
1319 | ||
1320 | return len; | |
1321 | } | |
48ead020 FW |
1322 | EXPORT_SYMBOL_GPL(trace_vbprintk); |
1323 | ||
40ce74f1 | 1324 | int trace_vprintk(unsigned long ip, const char *fmt, va_list args) |
48ead020 FW |
1325 | { |
1326 | static raw_spinlock_t trace_buf_lock = __RAW_SPIN_LOCK_UNLOCKED; | |
1327 | static char trace_buf[TRACE_BUF_SIZE]; | |
1328 | ||
e1112b4d | 1329 | struct ftrace_event_call *call = &event_print; |
48ead020 FW |
1330 | struct ring_buffer_event *event; |
1331 | struct trace_array *tr = &global_trace; | |
1332 | struct trace_array_cpu *data; | |
1333 | int cpu, len = 0, size, pc; | |
1334 | struct print_entry *entry; | |
1335 | unsigned long irq_flags; | |
3189cdb3 | 1336 | int disable; |
48ead020 FW |
1337 | |
1338 | if (tracing_disabled || tracing_selftest_running) | |
1339 | return 0; | |
1340 | ||
1341 | pc = preempt_count(); | |
1342 | preempt_disable_notrace(); | |
1343 | cpu = raw_smp_processor_id(); | |
1344 | data = tr->data[cpu]; | |
1345 | ||
3189cdb3 SR |
1346 | disable = atomic_inc_return(&data->disabled); |
1347 | if (unlikely(disable != 1)) | |
48ead020 FW |
1348 | goto out; |
1349 | ||
1350 | pause_graph_tracing(); | |
1351 | raw_local_irq_save(irq_flags); | |
1352 | __raw_spin_lock(&trace_buf_lock); | |
1353 | len = vsnprintf(trace_buf, TRACE_BUF_SIZE, fmt, args); | |
1354 | ||
1355 | len = min(len, TRACE_BUF_SIZE-1); | |
1356 | trace_buf[len] = 0; | |
1357 | ||
1358 | size = sizeof(*entry) + len + 1; | |
1359 | event = trace_buffer_lock_reserve(tr, TRACE_PRINT, size, irq_flags, pc); | |
1360 | if (!event) | |
1361 | goto out_unlock; | |
1362 | entry = ring_buffer_event_data(event); | |
1363 | entry->ip = ip; | |
48ead020 FW |
1364 | |
1365 | memcpy(&entry->buf, trace_buf, len); | |
1366 | entry->buf[len] = 0; | |
eb02ce01 TZ |
1367 | if (!filter_check_discard(call, entry, tr->buffer, event)) |
1368 | ring_buffer_unlock_commit(tr->buffer, event); | |
48ead020 FW |
1369 | |
1370 | out_unlock: | |
1371 | __raw_spin_unlock(&trace_buf_lock); | |
1372 | raw_local_irq_restore(irq_flags); | |
1373 | unpause_graph_tracing(); | |
1374 | out: | |
3189cdb3 | 1375 | atomic_dec_return(&data->disabled); |
48ead020 FW |
1376 | preempt_enable_notrace(); |
1377 | ||
1378 | return len; | |
1379 | } | |
769b0441 FW |
1380 | EXPORT_SYMBOL_GPL(trace_vprintk); |
1381 | ||
bc0c38d1 SR |
1382 | enum trace_file_type { |
1383 | TRACE_FILE_LAT_FMT = 1, | |
12ef7d44 | 1384 | TRACE_FILE_ANNOTATE = 2, |
bc0c38d1 SR |
1385 | }; |
1386 | ||
e2ac8ef5 | 1387 | static void trace_iterator_increment(struct trace_iterator *iter) |
5a90f577 | 1388 | { |
d769041f SR |
1389 | /* Don't allow ftrace to trace into the ring buffers */ |
1390 | ftrace_disable_cpu(); | |
1391 | ||
5a90f577 | 1392 | iter->idx++; |
d769041f SR |
1393 | if (iter->buffer_iter[iter->cpu]) |
1394 | ring_buffer_read(iter->buffer_iter[iter->cpu], NULL); | |
1395 | ||
1396 | ftrace_enable_cpu(); | |
5a90f577 SR |
1397 | } |
1398 | ||
e309b41d | 1399 | static struct trace_entry * |
3928a8a2 | 1400 | peek_next_entry(struct trace_iterator *iter, int cpu, u64 *ts) |
dd0e545f | 1401 | { |
3928a8a2 SR |
1402 | struct ring_buffer_event *event; |
1403 | struct ring_buffer_iter *buf_iter = iter->buffer_iter[cpu]; | |
dd0e545f | 1404 | |
d769041f SR |
1405 | /* Don't allow ftrace to trace into the ring buffers */ |
1406 | ftrace_disable_cpu(); | |
1407 | ||
1408 | if (buf_iter) | |
1409 | event = ring_buffer_iter_peek(buf_iter, ts); | |
1410 | else | |
1411 | event = ring_buffer_peek(iter->tr->buffer, cpu, ts); | |
1412 | ||
1413 | ftrace_enable_cpu(); | |
1414 | ||
3928a8a2 | 1415 | return event ? ring_buffer_event_data(event) : NULL; |
dd0e545f | 1416 | } |
d769041f | 1417 | |
dd0e545f | 1418 | static struct trace_entry * |
3928a8a2 | 1419 | __find_next_entry(struct trace_iterator *iter, int *ent_cpu, u64 *ent_ts) |
bc0c38d1 | 1420 | { |
3928a8a2 | 1421 | struct ring_buffer *buffer = iter->tr->buffer; |
bc0c38d1 | 1422 | struct trace_entry *ent, *next = NULL; |
b04cc6b1 | 1423 | int cpu_file = iter->cpu_file; |
3928a8a2 | 1424 | u64 next_ts = 0, ts; |
bc0c38d1 SR |
1425 | int next_cpu = -1; |
1426 | int cpu; | |
1427 | ||
b04cc6b1 FW |
1428 | /* |
1429 | * If we are in a per_cpu trace file, don't bother by iterating over | |
1430 | * all cpu and peek directly. | |
1431 | */ | |
1432 | if (cpu_file > TRACE_PIPE_ALL_CPU) { | |
1433 | if (ring_buffer_empty_cpu(buffer, cpu_file)) | |
1434 | return NULL; | |
1435 | ent = peek_next_entry(iter, cpu_file, ent_ts); | |
1436 | if (ent_cpu) | |
1437 | *ent_cpu = cpu_file; | |
1438 | ||
1439 | return ent; | |
1440 | } | |
1441 | ||
ab46428c | 1442 | for_each_tracing_cpu(cpu) { |
dd0e545f | 1443 | |
3928a8a2 SR |
1444 | if (ring_buffer_empty_cpu(buffer, cpu)) |
1445 | continue; | |
dd0e545f | 1446 | |
3928a8a2 | 1447 | ent = peek_next_entry(iter, cpu, &ts); |
dd0e545f | 1448 | |
cdd31cd2 IM |
1449 | /* |
1450 | * Pick the entry with the smallest timestamp: | |
1451 | */ | |
3928a8a2 | 1452 | if (ent && (!next || ts < next_ts)) { |
bc0c38d1 SR |
1453 | next = ent; |
1454 | next_cpu = cpu; | |
3928a8a2 | 1455 | next_ts = ts; |
bc0c38d1 SR |
1456 | } |
1457 | } | |
1458 | ||
1459 | if (ent_cpu) | |
1460 | *ent_cpu = next_cpu; | |
1461 | ||
3928a8a2 SR |
1462 | if (ent_ts) |
1463 | *ent_ts = next_ts; | |
1464 | ||
bc0c38d1 SR |
1465 | return next; |
1466 | } | |
1467 | ||
dd0e545f | 1468 | /* Find the next real entry, without updating the iterator itself */ |
c4a8e8be FW |
1469 | struct trace_entry *trace_find_next_entry(struct trace_iterator *iter, |
1470 | int *ent_cpu, u64 *ent_ts) | |
bc0c38d1 | 1471 | { |
3928a8a2 | 1472 | return __find_next_entry(iter, ent_cpu, ent_ts); |
dd0e545f SR |
1473 | } |
1474 | ||
1475 | /* Find the next real entry, and increment the iterator to the next entry */ | |
1476 | static void *find_next_entry_inc(struct trace_iterator *iter) | |
1477 | { | |
3928a8a2 | 1478 | iter->ent = __find_next_entry(iter, &iter->cpu, &iter->ts); |
dd0e545f | 1479 | |
3928a8a2 | 1480 | if (iter->ent) |
e2ac8ef5 | 1481 | trace_iterator_increment(iter); |
dd0e545f | 1482 | |
3928a8a2 | 1483 | return iter->ent ? iter : NULL; |
b3806b43 | 1484 | } |
bc0c38d1 | 1485 | |
e309b41d | 1486 | static void trace_consume(struct trace_iterator *iter) |
b3806b43 | 1487 | { |
d769041f SR |
1488 | /* Don't allow ftrace to trace into the ring buffers */ |
1489 | ftrace_disable_cpu(); | |
3928a8a2 | 1490 | ring_buffer_consume(iter->tr->buffer, iter->cpu, &iter->ts); |
d769041f | 1491 | ftrace_enable_cpu(); |
bc0c38d1 SR |
1492 | } |
1493 | ||
e309b41d | 1494 | static void *s_next(struct seq_file *m, void *v, loff_t *pos) |
bc0c38d1 SR |
1495 | { |
1496 | struct trace_iterator *iter = m->private; | |
bc0c38d1 | 1497 | int i = (int)*pos; |
4e3c3333 | 1498 | void *ent; |
bc0c38d1 SR |
1499 | |
1500 | (*pos)++; | |
1501 | ||
1502 | /* can't go backwards */ | |
1503 | if (iter->idx > i) | |
1504 | return NULL; | |
1505 | ||
1506 | if (iter->idx < 0) | |
1507 | ent = find_next_entry_inc(iter); | |
1508 | else | |
1509 | ent = iter; | |
1510 | ||
1511 | while (ent && iter->idx < i) | |
1512 | ent = find_next_entry_inc(iter); | |
1513 | ||
1514 | iter->pos = *pos; | |
1515 | ||
bc0c38d1 SR |
1516 | return ent; |
1517 | } | |
1518 | ||
d7350c3f FW |
1519 | /* |
1520 | * No necessary locking here. The worst thing which can | |
1521 | * happen is loosing events consumed at the same time | |
1522 | * by a trace_pipe reader. | |
1523 | * Other than that, we don't risk to crash the ring buffer | |
1524 | * because it serializes the readers. | |
1525 | * | |
1526 | * The current tracer is copied to avoid a global locking | |
1527 | * all around. | |
1528 | */ | |
bc0c38d1 SR |
1529 | static void *s_start(struct seq_file *m, loff_t *pos) |
1530 | { | |
1531 | struct trace_iterator *iter = m->private; | |
d7350c3f | 1532 | static struct tracer *old_tracer; |
b04cc6b1 | 1533 | int cpu_file = iter->cpu_file; |
bc0c38d1 SR |
1534 | void *p = NULL; |
1535 | loff_t l = 0; | |
3928a8a2 | 1536 | int cpu; |
bc0c38d1 | 1537 | |
d7350c3f | 1538 | /* copy the tracer to avoid using a global lock all around */ |
bc0c38d1 | 1539 | mutex_lock(&trace_types_lock); |
d7350c3f FW |
1540 | if (unlikely(old_tracer != current_trace && current_trace)) { |
1541 | old_tracer = current_trace; | |
1542 | *iter->trace = *current_trace; | |
d15f57f2 | 1543 | } |
d7350c3f | 1544 | mutex_unlock(&trace_types_lock); |
bc0c38d1 SR |
1545 | |
1546 | atomic_inc(&trace_record_cmdline_disabled); | |
1547 | ||
bc0c38d1 SR |
1548 | if (*pos != iter->pos) { |
1549 | iter->ent = NULL; | |
1550 | iter->cpu = 0; | |
1551 | iter->idx = -1; | |
1552 | ||
d769041f SR |
1553 | ftrace_disable_cpu(); |
1554 | ||
b04cc6b1 FW |
1555 | if (cpu_file == TRACE_PIPE_ALL_CPU) { |
1556 | for_each_tracing_cpu(cpu) | |
1557 | ring_buffer_iter_reset(iter->buffer_iter[cpu]); | |
1558 | } else | |
1559 | ring_buffer_iter_reset(iter->buffer_iter[cpu_file]); | |
1560 | ||
bc0c38d1 | 1561 | |
d769041f SR |
1562 | ftrace_enable_cpu(); |
1563 | ||
bc0c38d1 SR |
1564 | for (p = iter; p && l < *pos; p = s_next(m, p, &l)) |
1565 | ; | |
1566 | ||
1567 | } else { | |
4c11d7ae | 1568 | l = *pos - 1; |
bc0c38d1 SR |
1569 | p = s_next(m, p, &l); |
1570 | } | |
1571 | ||
1572 | return p; | |
1573 | } | |
1574 | ||
1575 | static void s_stop(struct seq_file *m, void *p) | |
1576 | { | |
bc0c38d1 | 1577 | atomic_dec(&trace_record_cmdline_disabled); |
bc0c38d1 SR |
1578 | } |
1579 | ||
e309b41d | 1580 | static void print_lat_help_header(struct seq_file *m) |
bc0c38d1 | 1581 | { |
a6168353 ME |
1582 | seq_puts(m, "# _------=> CPU# \n"); |
1583 | seq_puts(m, "# / _-----=> irqs-off \n"); | |
1584 | seq_puts(m, "# | / _----=> need-resched \n"); | |
1585 | seq_puts(m, "# || / _---=> hardirq/softirq \n"); | |
1586 | seq_puts(m, "# ||| / _--=> preempt-depth \n"); | |
1587 | seq_puts(m, "# |||| / \n"); | |
1588 | seq_puts(m, "# ||||| delay \n"); | |
1589 | seq_puts(m, "# cmd pid ||||| time | caller \n"); | |
1590 | seq_puts(m, "# \\ / ||||| \\ | / \n"); | |
bc0c38d1 SR |
1591 | } |
1592 | ||
e309b41d | 1593 | static void print_func_help_header(struct seq_file *m) |
bc0c38d1 | 1594 | { |
a6168353 ME |
1595 | seq_puts(m, "# TASK-PID CPU# TIMESTAMP FUNCTION\n"); |
1596 | seq_puts(m, "# | | | | |\n"); | |
bc0c38d1 SR |
1597 | } |
1598 | ||
1599 | ||
e309b41d | 1600 | static void |
bc0c38d1 SR |
1601 | print_trace_header(struct seq_file *m, struct trace_iterator *iter) |
1602 | { | |
1603 | unsigned long sym_flags = (trace_flags & TRACE_ITER_SYM_MASK); | |
1604 | struct trace_array *tr = iter->tr; | |
1605 | struct trace_array_cpu *data = tr->data[tr->cpu]; | |
1606 | struct tracer *type = current_trace; | |
3928a8a2 SR |
1607 | unsigned long total; |
1608 | unsigned long entries; | |
bc0c38d1 SR |
1609 | const char *name = "preemption"; |
1610 | ||
1611 | if (type) | |
1612 | name = type->name; | |
1613 | ||
3928a8a2 SR |
1614 | entries = ring_buffer_entries(iter->tr->buffer); |
1615 | total = entries + | |
1616 | ring_buffer_overruns(iter->tr->buffer); | |
bc0c38d1 | 1617 | |
888b55dc | 1618 | seq_printf(m, "# %s latency trace v1.1.5 on %s\n", |
bc0c38d1 | 1619 | name, UTS_RELEASE); |
888b55dc | 1620 | seq_puts(m, "# -----------------------------------" |
bc0c38d1 | 1621 | "---------------------------------\n"); |
888b55dc | 1622 | seq_printf(m, "# latency: %lu us, #%lu/%lu, CPU#%d |" |
bc0c38d1 | 1623 | " (M:%s VP:%d, KP:%d, SP:%d HP:%d", |
57f50be1 | 1624 | nsecs_to_usecs(data->saved_latency), |
bc0c38d1 | 1625 | entries, |
4c11d7ae | 1626 | total, |
bc0c38d1 SR |
1627 | tr->cpu, |
1628 | #if defined(CONFIG_PREEMPT_NONE) | |
1629 | "server", | |
1630 | #elif defined(CONFIG_PREEMPT_VOLUNTARY) | |
1631 | "desktop", | |
b5c21b45 | 1632 | #elif defined(CONFIG_PREEMPT) |
bc0c38d1 SR |
1633 | "preempt", |
1634 | #else | |
1635 | "unknown", | |
1636 | #endif | |
1637 | /* These are reserved for later use */ | |
1638 | 0, 0, 0, 0); | |
1639 | #ifdef CONFIG_SMP | |
1640 | seq_printf(m, " #P:%d)\n", num_online_cpus()); | |
1641 | #else | |
1642 | seq_puts(m, ")\n"); | |
1643 | #endif | |
888b55dc KM |
1644 | seq_puts(m, "# -----------------\n"); |
1645 | seq_printf(m, "# | task: %.16s-%d " | |
bc0c38d1 SR |
1646 | "(uid:%d nice:%ld policy:%ld rt_prio:%ld)\n", |
1647 | data->comm, data->pid, data->uid, data->nice, | |
1648 | data->policy, data->rt_priority); | |
888b55dc | 1649 | seq_puts(m, "# -----------------\n"); |
bc0c38d1 SR |
1650 | |
1651 | if (data->critical_start) { | |
888b55dc | 1652 | seq_puts(m, "# => started at: "); |
214023c3 SR |
1653 | seq_print_ip_sym(&iter->seq, data->critical_start, sym_flags); |
1654 | trace_print_seq(m, &iter->seq); | |
888b55dc | 1655 | seq_puts(m, "\n# => ended at: "); |
214023c3 SR |
1656 | seq_print_ip_sym(&iter->seq, data->critical_end, sym_flags); |
1657 | trace_print_seq(m, &iter->seq); | |
888b55dc | 1658 | seq_puts(m, "#\n"); |
bc0c38d1 SR |
1659 | } |
1660 | ||
888b55dc | 1661 | seq_puts(m, "#\n"); |
bc0c38d1 SR |
1662 | } |
1663 | ||
a309720c SR |
1664 | static void test_cpu_buff_start(struct trace_iterator *iter) |
1665 | { | |
1666 | struct trace_seq *s = &iter->seq; | |
1667 | ||
12ef7d44 SR |
1668 | if (!(trace_flags & TRACE_ITER_ANNOTATE)) |
1669 | return; | |
1670 | ||
1671 | if (!(iter->iter_flags & TRACE_FILE_ANNOTATE)) | |
1672 | return; | |
1673 | ||
4462344e | 1674 | if (cpumask_test_cpu(iter->cpu, iter->started)) |
a309720c SR |
1675 | return; |
1676 | ||
4462344e | 1677 | cpumask_set_cpu(iter->cpu, iter->started); |
b0dfa978 FW |
1678 | |
1679 | /* Don't print started cpu buffer for the first entry of the trace */ | |
1680 | if (iter->idx > 1) | |
1681 | trace_seq_printf(s, "##### CPU %u buffer started ####\n", | |
1682 | iter->cpu); | |
a309720c SR |
1683 | } |
1684 | ||
2c4f035f | 1685 | static enum print_line_t print_trace_fmt(struct trace_iterator *iter) |
bc0c38d1 | 1686 | { |
214023c3 | 1687 | struct trace_seq *s = &iter->seq; |
bc0c38d1 | 1688 | unsigned long sym_flags = (trace_flags & TRACE_ITER_SYM_MASK); |
4e3c3333 | 1689 | struct trace_entry *entry; |
f633cef0 | 1690 | struct trace_event *event; |
bc0c38d1 | 1691 | |
4e3c3333 | 1692 | entry = iter->ent; |
dd0e545f | 1693 | |
a309720c SR |
1694 | test_cpu_buff_start(iter); |
1695 | ||
c4a8e8be | 1696 | event = ftrace_find_event(entry->type); |
bc0c38d1 | 1697 | |
c4a8e8be | 1698 | if (trace_flags & TRACE_ITER_CONTEXT_INFO) { |
27d48be8 SR |
1699 | if (iter->iter_flags & TRACE_FILE_LAT_FMT) { |
1700 | if (!trace_print_lat_context(iter)) | |
1701 | goto partial; | |
1702 | } else { | |
1703 | if (!trace_print_context(iter)) | |
1704 | goto partial; | |
1705 | } | |
c4a8e8be | 1706 | } |
bc0c38d1 | 1707 | |
268ccda0 | 1708 | if (event) |
d9793bd8 ACM |
1709 | return event->trace(iter, sym_flags); |
1710 | ||
1711 | if (!trace_seq_printf(s, "Unknown type %d\n", entry->type)) | |
1712 | goto partial; | |
02b67518 | 1713 | |
2c4f035f | 1714 | return TRACE_TYPE_HANDLED; |
d9793bd8 ACM |
1715 | partial: |
1716 | return TRACE_TYPE_PARTIAL_LINE; | |
bc0c38d1 SR |
1717 | } |
1718 | ||
2c4f035f | 1719 | static enum print_line_t print_raw_fmt(struct trace_iterator *iter) |
f9896bf3 IM |
1720 | { |
1721 | struct trace_seq *s = &iter->seq; | |
1722 | struct trace_entry *entry; | |
f633cef0 | 1723 | struct trace_event *event; |
f9896bf3 IM |
1724 | |
1725 | entry = iter->ent; | |
dd0e545f | 1726 | |
c4a8e8be | 1727 | if (trace_flags & TRACE_ITER_CONTEXT_INFO) { |
d9793bd8 ACM |
1728 | if (!trace_seq_printf(s, "%d %d %llu ", |
1729 | entry->pid, iter->cpu, iter->ts)) | |
1730 | goto partial; | |
c4a8e8be | 1731 | } |
f9896bf3 | 1732 | |
f633cef0 | 1733 | event = ftrace_find_event(entry->type); |
268ccda0 | 1734 | if (event) |
d9793bd8 ACM |
1735 | return event->raw(iter, 0); |
1736 | ||
1737 | if (!trace_seq_printf(s, "%d ?\n", entry->type)) | |
1738 | goto partial; | |
777e208d | 1739 | |
2c4f035f | 1740 | return TRACE_TYPE_HANDLED; |
d9793bd8 ACM |
1741 | partial: |
1742 | return TRACE_TYPE_PARTIAL_LINE; | |
f9896bf3 IM |
1743 | } |
1744 | ||
2c4f035f | 1745 | static enum print_line_t print_hex_fmt(struct trace_iterator *iter) |
5e3ca0ec IM |
1746 | { |
1747 | struct trace_seq *s = &iter->seq; | |
1748 | unsigned char newline = '\n'; | |
1749 | struct trace_entry *entry; | |
f633cef0 | 1750 | struct trace_event *event; |
5e3ca0ec IM |
1751 | |
1752 | entry = iter->ent; | |
dd0e545f | 1753 | |
c4a8e8be FW |
1754 | if (trace_flags & TRACE_ITER_CONTEXT_INFO) { |
1755 | SEQ_PUT_HEX_FIELD_RET(s, entry->pid); | |
1756 | SEQ_PUT_HEX_FIELD_RET(s, iter->cpu); | |
1757 | SEQ_PUT_HEX_FIELD_RET(s, iter->ts); | |
1758 | } | |
5e3ca0ec | 1759 | |
f633cef0 | 1760 | event = ftrace_find_event(entry->type); |
268ccda0 | 1761 | if (event) { |
ae7462b4 | 1762 | enum print_line_t ret = event->hex(iter, 0); |
d9793bd8 ACM |
1763 | if (ret != TRACE_TYPE_HANDLED) |
1764 | return ret; | |
1765 | } | |
7104f300 | 1766 | |
5e3ca0ec IM |
1767 | SEQ_PUT_FIELD_RET(s, newline); |
1768 | ||
2c4f035f | 1769 | return TRACE_TYPE_HANDLED; |
5e3ca0ec IM |
1770 | } |
1771 | ||
2c4f035f | 1772 | static enum print_line_t print_bin_fmt(struct trace_iterator *iter) |
cb0f12aa IM |
1773 | { |
1774 | struct trace_seq *s = &iter->seq; | |
1775 | struct trace_entry *entry; | |
f633cef0 | 1776 | struct trace_event *event; |
cb0f12aa IM |
1777 | |
1778 | entry = iter->ent; | |
dd0e545f | 1779 | |
c4a8e8be FW |
1780 | if (trace_flags & TRACE_ITER_CONTEXT_INFO) { |
1781 | SEQ_PUT_FIELD_RET(s, entry->pid); | |
1830b52d | 1782 | SEQ_PUT_FIELD_RET(s, iter->cpu); |
c4a8e8be FW |
1783 | SEQ_PUT_FIELD_RET(s, iter->ts); |
1784 | } | |
cb0f12aa | 1785 | |
f633cef0 | 1786 | event = ftrace_find_event(entry->type); |
268ccda0 | 1787 | return event ? event->binary(iter, 0) : TRACE_TYPE_HANDLED; |
cb0f12aa IM |
1788 | } |
1789 | ||
bc0c38d1 SR |
1790 | static int trace_empty(struct trace_iterator *iter) |
1791 | { | |
bc0c38d1 SR |
1792 | int cpu; |
1793 | ||
9aba60fe SR |
1794 | /* If we are looking at one CPU buffer, only check that one */ |
1795 | if (iter->cpu_file != TRACE_PIPE_ALL_CPU) { | |
1796 | cpu = iter->cpu_file; | |
1797 | if (iter->buffer_iter[cpu]) { | |
1798 | if (!ring_buffer_iter_empty(iter->buffer_iter[cpu])) | |
1799 | return 0; | |
1800 | } else { | |
1801 | if (!ring_buffer_empty_cpu(iter->tr->buffer, cpu)) | |
1802 | return 0; | |
1803 | } | |
1804 | return 1; | |
1805 | } | |
1806 | ||
ab46428c | 1807 | for_each_tracing_cpu(cpu) { |
d769041f SR |
1808 | if (iter->buffer_iter[cpu]) { |
1809 | if (!ring_buffer_iter_empty(iter->buffer_iter[cpu])) | |
1810 | return 0; | |
1811 | } else { | |
1812 | if (!ring_buffer_empty_cpu(iter->tr->buffer, cpu)) | |
1813 | return 0; | |
1814 | } | |
bc0c38d1 | 1815 | } |
d769041f | 1816 | |
797d3712 | 1817 | return 1; |
bc0c38d1 SR |
1818 | } |
1819 | ||
2c4f035f | 1820 | static enum print_line_t print_trace_line(struct trace_iterator *iter) |
f9896bf3 | 1821 | { |
2c4f035f FW |
1822 | enum print_line_t ret; |
1823 | ||
1824 | if (iter->trace && iter->trace->print_line) { | |
1825 | ret = iter->trace->print_line(iter); | |
1826 | if (ret != TRACE_TYPE_UNHANDLED) | |
1827 | return ret; | |
1828 | } | |
72829bc3 | 1829 | |
48ead020 FW |
1830 | if (iter->ent->type == TRACE_BPRINT && |
1831 | trace_flags & TRACE_ITER_PRINTK && | |
1832 | trace_flags & TRACE_ITER_PRINTK_MSGONLY) | |
5ef841f6 | 1833 | return trace_print_bprintk_msg_only(iter); |
48ead020 | 1834 | |
66896a85 FW |
1835 | if (iter->ent->type == TRACE_PRINT && |
1836 | trace_flags & TRACE_ITER_PRINTK && | |
1837 | trace_flags & TRACE_ITER_PRINTK_MSGONLY) | |
5ef841f6 | 1838 | return trace_print_printk_msg_only(iter); |
66896a85 | 1839 | |
cb0f12aa IM |
1840 | if (trace_flags & TRACE_ITER_BIN) |
1841 | return print_bin_fmt(iter); | |
1842 | ||
5e3ca0ec IM |
1843 | if (trace_flags & TRACE_ITER_HEX) |
1844 | return print_hex_fmt(iter); | |
1845 | ||
f9896bf3 IM |
1846 | if (trace_flags & TRACE_ITER_RAW) |
1847 | return print_raw_fmt(iter); | |
1848 | ||
f9896bf3 IM |
1849 | return print_trace_fmt(iter); |
1850 | } | |
1851 | ||
bc0c38d1 SR |
1852 | static int s_show(struct seq_file *m, void *v) |
1853 | { | |
1854 | struct trace_iterator *iter = v; | |
1855 | ||
1856 | if (iter->ent == NULL) { | |
1857 | if (iter->tr) { | |
1858 | seq_printf(m, "# tracer: %s\n", iter->trace->name); | |
1859 | seq_puts(m, "#\n"); | |
1860 | } | |
8bba1bf5 MM |
1861 | if (iter->trace && iter->trace->print_header) |
1862 | iter->trace->print_header(m); | |
1863 | else if (iter->iter_flags & TRACE_FILE_LAT_FMT) { | |
bc0c38d1 SR |
1864 | /* print nothing if the buffers are empty */ |
1865 | if (trace_empty(iter)) | |
1866 | return 0; | |
1867 | print_trace_header(m, iter); | |
1868 | if (!(trace_flags & TRACE_ITER_VERBOSE)) | |
1869 | print_lat_help_header(m); | |
1870 | } else { | |
1871 | if (!(trace_flags & TRACE_ITER_VERBOSE)) | |
1872 | print_func_help_header(m); | |
1873 | } | |
1874 | } else { | |
f9896bf3 | 1875 | print_trace_line(iter); |
214023c3 | 1876 | trace_print_seq(m, &iter->seq); |
bc0c38d1 SR |
1877 | } |
1878 | ||
1879 | return 0; | |
1880 | } | |
1881 | ||
1882 | static struct seq_operations tracer_seq_ops = { | |
4bf39a94 IM |
1883 | .start = s_start, |
1884 | .next = s_next, | |
1885 | .stop = s_stop, | |
1886 | .show = s_show, | |
bc0c38d1 SR |
1887 | }; |
1888 | ||
e309b41d | 1889 | static struct trace_iterator * |
85a2f9b4 | 1890 | __tracing_open(struct inode *inode, struct file *file) |
bc0c38d1 | 1891 | { |
b04cc6b1 | 1892 | long cpu_file = (long) inode->i_private; |
85a2f9b4 | 1893 | void *fail_ret = ERR_PTR(-ENOMEM); |
bc0c38d1 | 1894 | struct trace_iterator *iter; |
3928a8a2 | 1895 | struct seq_file *m; |
85a2f9b4 | 1896 | int cpu, ret; |
bc0c38d1 | 1897 | |
85a2f9b4 SR |
1898 | if (tracing_disabled) |
1899 | return ERR_PTR(-ENODEV); | |
60a11774 | 1900 | |
bc0c38d1 | 1901 | iter = kzalloc(sizeof(*iter), GFP_KERNEL); |
85a2f9b4 SR |
1902 | if (!iter) |
1903 | return ERR_PTR(-ENOMEM); | |
bc0c38d1 | 1904 | |
d7350c3f FW |
1905 | /* |
1906 | * We make a copy of the current tracer to avoid concurrent | |
1907 | * changes on it while we are reading. | |
1908 | */ | |
bc0c38d1 | 1909 | mutex_lock(&trace_types_lock); |
d7350c3f | 1910 | iter->trace = kzalloc(sizeof(*iter->trace), GFP_KERNEL); |
85a2f9b4 | 1911 | if (!iter->trace) |
d7350c3f | 1912 | goto fail; |
85a2f9b4 | 1913 | |
d7350c3f FW |
1914 | if (current_trace) |
1915 | *iter->trace = *current_trace; | |
1916 | ||
b0dfa978 FW |
1917 | if (!alloc_cpumask_var(&iter->started, GFP_KERNEL)) |
1918 | goto fail; | |
1919 | ||
1920 | cpumask_clear(iter->started); | |
1921 | ||
bc0c38d1 SR |
1922 | if (current_trace && current_trace->print_max) |
1923 | iter->tr = &max_tr; | |
1924 | else | |
b04cc6b1 | 1925 | iter->tr = &global_trace; |
bc0c38d1 | 1926 | iter->pos = -1; |
d7350c3f | 1927 | mutex_init(&iter->mutex); |
b04cc6b1 | 1928 | iter->cpu_file = cpu_file; |
bc0c38d1 | 1929 | |
8bba1bf5 MM |
1930 | /* Notify the tracer early; before we stop tracing. */ |
1931 | if (iter->trace && iter->trace->open) | |
a93751ca | 1932 | iter->trace->open(iter); |
8bba1bf5 | 1933 | |
12ef7d44 SR |
1934 | /* Annotate start of buffers if we had overruns */ |
1935 | if (ring_buffer_overruns(iter->tr->buffer)) | |
1936 | iter->iter_flags |= TRACE_FILE_ANNOTATE; | |
1937 | ||
b04cc6b1 FW |
1938 | if (iter->cpu_file == TRACE_PIPE_ALL_CPU) { |
1939 | for_each_tracing_cpu(cpu) { | |
12ef7d44 | 1940 | |
b04cc6b1 FW |
1941 | iter->buffer_iter[cpu] = |
1942 | ring_buffer_read_start(iter->tr->buffer, cpu); | |
b04cc6b1 FW |
1943 | } |
1944 | } else { | |
1945 | cpu = iter->cpu_file; | |
3928a8a2 | 1946 | iter->buffer_iter[cpu] = |
b04cc6b1 | 1947 | ring_buffer_read_start(iter->tr->buffer, cpu); |
3928a8a2 SR |
1948 | } |
1949 | ||
bc0c38d1 | 1950 | /* TODO stop tracer */ |
85a2f9b4 SR |
1951 | ret = seq_open(file, &tracer_seq_ops); |
1952 | if (ret < 0) { | |
1953 | fail_ret = ERR_PTR(ret); | |
3928a8a2 | 1954 | goto fail_buffer; |
85a2f9b4 | 1955 | } |
bc0c38d1 | 1956 | |
3928a8a2 SR |
1957 | m = file->private_data; |
1958 | m->private = iter; | |
bc0c38d1 | 1959 | |
3928a8a2 | 1960 | /* stop the trace while dumping */ |
9036990d | 1961 | tracing_stop(); |
3928a8a2 | 1962 | |
bc0c38d1 SR |
1963 | mutex_unlock(&trace_types_lock); |
1964 | ||
bc0c38d1 | 1965 | return iter; |
3928a8a2 SR |
1966 | |
1967 | fail_buffer: | |
1968 | for_each_tracing_cpu(cpu) { | |
1969 | if (iter->buffer_iter[cpu]) | |
1970 | ring_buffer_read_finish(iter->buffer_iter[cpu]); | |
1971 | } | |
b0dfa978 | 1972 | free_cpumask_var(iter->started); |
d7350c3f | 1973 | fail: |
3928a8a2 | 1974 | mutex_unlock(&trace_types_lock); |
d7350c3f | 1975 | kfree(iter->trace); |
0bb943c7 | 1976 | kfree(iter); |
3928a8a2 | 1977 | |
85a2f9b4 | 1978 | return fail_ret; |
bc0c38d1 SR |
1979 | } |
1980 | ||
1981 | int tracing_open_generic(struct inode *inode, struct file *filp) | |
1982 | { | |
60a11774 SR |
1983 | if (tracing_disabled) |
1984 | return -ENODEV; | |
1985 | ||
bc0c38d1 SR |
1986 | filp->private_data = inode->i_private; |
1987 | return 0; | |
1988 | } | |
1989 | ||
4fd27358 | 1990 | static int tracing_release(struct inode *inode, struct file *file) |
bc0c38d1 SR |
1991 | { |
1992 | struct seq_file *m = (struct seq_file *)file->private_data; | |
4acd4d00 | 1993 | struct trace_iterator *iter; |
3928a8a2 | 1994 | int cpu; |
bc0c38d1 | 1995 | |
4acd4d00 SR |
1996 | if (!(file->f_mode & FMODE_READ)) |
1997 | return 0; | |
1998 | ||
1999 | iter = m->private; | |
2000 | ||
bc0c38d1 | 2001 | mutex_lock(&trace_types_lock); |
3928a8a2 SR |
2002 | for_each_tracing_cpu(cpu) { |
2003 | if (iter->buffer_iter[cpu]) | |
2004 | ring_buffer_read_finish(iter->buffer_iter[cpu]); | |
2005 | } | |
2006 | ||
bc0c38d1 SR |
2007 | if (iter->trace && iter->trace->close) |
2008 | iter->trace->close(iter); | |
2009 | ||
2010 | /* reenable tracing if it was previously enabled */ | |
9036990d | 2011 | tracing_start(); |
bc0c38d1 SR |
2012 | mutex_unlock(&trace_types_lock); |
2013 | ||
2014 | seq_release(inode, file); | |
d7350c3f | 2015 | mutex_destroy(&iter->mutex); |
b0dfa978 | 2016 | free_cpumask_var(iter->started); |
d7350c3f | 2017 | kfree(iter->trace); |
bc0c38d1 SR |
2018 | kfree(iter); |
2019 | return 0; | |
2020 | } | |
2021 | ||
2022 | static int tracing_open(struct inode *inode, struct file *file) | |
2023 | { | |
85a2f9b4 SR |
2024 | struct trace_iterator *iter; |
2025 | int ret = 0; | |
bc0c38d1 | 2026 | |
4acd4d00 SR |
2027 | /* If this file was open for write, then erase contents */ |
2028 | if ((file->f_mode & FMODE_WRITE) && | |
2029 | !(file->f_flags & O_APPEND)) { | |
2030 | long cpu = (long) inode->i_private; | |
bc0c38d1 | 2031 | |
4acd4d00 SR |
2032 | if (cpu == TRACE_PIPE_ALL_CPU) |
2033 | tracing_reset_online_cpus(&global_trace); | |
2034 | else | |
2035 | tracing_reset(&global_trace, cpu); | |
2036 | } | |
bc0c38d1 | 2037 | |
4acd4d00 SR |
2038 | if (file->f_mode & FMODE_READ) { |
2039 | iter = __tracing_open(inode, file); | |
2040 | if (IS_ERR(iter)) | |
2041 | ret = PTR_ERR(iter); | |
2042 | else if (trace_flags & TRACE_ITER_LATENCY_FMT) | |
2043 | iter->iter_flags |= TRACE_FILE_LAT_FMT; | |
2044 | } | |
bc0c38d1 SR |
2045 | return ret; |
2046 | } | |
2047 | ||
e309b41d | 2048 | static void * |
bc0c38d1 SR |
2049 | t_next(struct seq_file *m, void *v, loff_t *pos) |
2050 | { | |
2051 | struct tracer *t = m->private; | |
2052 | ||
2053 | (*pos)++; | |
2054 | ||
2055 | if (t) | |
2056 | t = t->next; | |
2057 | ||
2058 | m->private = t; | |
2059 | ||
2060 | return t; | |
2061 | } | |
2062 | ||
2063 | static void *t_start(struct seq_file *m, loff_t *pos) | |
2064 | { | |
2065 | struct tracer *t = m->private; | |
2066 | loff_t l = 0; | |
2067 | ||
2068 | mutex_lock(&trace_types_lock); | |
2069 | for (; t && l < *pos; t = t_next(m, t, &l)) | |
2070 | ; | |
2071 | ||
2072 | return t; | |
2073 | } | |
2074 | ||
2075 | static void t_stop(struct seq_file *m, void *p) | |
2076 | { | |
2077 | mutex_unlock(&trace_types_lock); | |
2078 | } | |
2079 | ||
2080 | static int t_show(struct seq_file *m, void *v) | |
2081 | { | |
2082 | struct tracer *t = v; | |
2083 | ||
2084 | if (!t) | |
2085 | return 0; | |
2086 | ||
2087 | seq_printf(m, "%s", t->name); | |
2088 | if (t->next) | |
2089 | seq_putc(m, ' '); | |
2090 | else | |
2091 | seq_putc(m, '\n'); | |
2092 | ||
2093 | return 0; | |
2094 | } | |
2095 | ||
2096 | static struct seq_operations show_traces_seq_ops = { | |
4bf39a94 IM |
2097 | .start = t_start, |
2098 | .next = t_next, | |
2099 | .stop = t_stop, | |
2100 | .show = t_show, | |
bc0c38d1 SR |
2101 | }; |
2102 | ||
2103 | static int show_traces_open(struct inode *inode, struct file *file) | |
2104 | { | |
2105 | int ret; | |
2106 | ||
60a11774 SR |
2107 | if (tracing_disabled) |
2108 | return -ENODEV; | |
2109 | ||
bc0c38d1 SR |
2110 | ret = seq_open(file, &show_traces_seq_ops); |
2111 | if (!ret) { | |
2112 | struct seq_file *m = file->private_data; | |
2113 | m->private = trace_types; | |
2114 | } | |
2115 | ||
2116 | return ret; | |
2117 | } | |
2118 | ||
4acd4d00 SR |
2119 | static ssize_t |
2120 | tracing_write_stub(struct file *filp, const char __user *ubuf, | |
2121 | size_t count, loff_t *ppos) | |
2122 | { | |
2123 | return count; | |
2124 | } | |
2125 | ||
5e2336a0 | 2126 | static const struct file_operations tracing_fops = { |
4bf39a94 IM |
2127 | .open = tracing_open, |
2128 | .read = seq_read, | |
4acd4d00 | 2129 | .write = tracing_write_stub, |
4bf39a94 IM |
2130 | .llseek = seq_lseek, |
2131 | .release = tracing_release, | |
bc0c38d1 SR |
2132 | }; |
2133 | ||
5e2336a0 | 2134 | static const struct file_operations show_traces_fops = { |
c7078de1 IM |
2135 | .open = show_traces_open, |
2136 | .read = seq_read, | |
2137 | .release = seq_release, | |
2138 | }; | |
2139 | ||
36dfe925 IM |
2140 | /* |
2141 | * Only trace on a CPU if the bitmask is set: | |
2142 | */ | |
9e01c1b7 | 2143 | static cpumask_var_t tracing_cpumask; |
36dfe925 IM |
2144 | |
2145 | /* | |
2146 | * The tracer itself will not take this lock, but still we want | |
2147 | * to provide a consistent cpumask to user-space: | |
2148 | */ | |
2149 | static DEFINE_MUTEX(tracing_cpumask_update_lock); | |
2150 | ||
2151 | /* | |
2152 | * Temporary storage for the character representation of the | |
2153 | * CPU bitmask (and one more byte for the newline): | |
2154 | */ | |
2155 | static char mask_str[NR_CPUS + 1]; | |
2156 | ||
c7078de1 IM |
2157 | static ssize_t |
2158 | tracing_cpumask_read(struct file *filp, char __user *ubuf, | |
2159 | size_t count, loff_t *ppos) | |
2160 | { | |
36dfe925 | 2161 | int len; |
c7078de1 IM |
2162 | |
2163 | mutex_lock(&tracing_cpumask_update_lock); | |
36dfe925 | 2164 | |
9e01c1b7 | 2165 | len = cpumask_scnprintf(mask_str, count, tracing_cpumask); |
36dfe925 IM |
2166 | if (count - len < 2) { |
2167 | count = -EINVAL; | |
2168 | goto out_err; | |
2169 | } | |
2170 | len += sprintf(mask_str + len, "\n"); | |
2171 | count = simple_read_from_buffer(ubuf, count, ppos, mask_str, NR_CPUS+1); | |
2172 | ||
2173 | out_err: | |
c7078de1 IM |
2174 | mutex_unlock(&tracing_cpumask_update_lock); |
2175 | ||
2176 | return count; | |
2177 | } | |
2178 | ||
2179 | static ssize_t | |
2180 | tracing_cpumask_write(struct file *filp, const char __user *ubuf, | |
2181 | size_t count, loff_t *ppos) | |
2182 | { | |
36dfe925 | 2183 | int err, cpu; |
9e01c1b7 RR |
2184 | cpumask_var_t tracing_cpumask_new; |
2185 | ||
2186 | if (!alloc_cpumask_var(&tracing_cpumask_new, GFP_KERNEL)) | |
2187 | return -ENOMEM; | |
c7078de1 IM |
2188 | |
2189 | mutex_lock(&tracing_cpumask_update_lock); | |
9e01c1b7 | 2190 | err = cpumask_parse_user(ubuf, count, tracing_cpumask_new); |
c7078de1 | 2191 | if (err) |
36dfe925 IM |
2192 | goto err_unlock; |
2193 | ||
a5e25883 | 2194 | local_irq_disable(); |
92205c23 | 2195 | __raw_spin_lock(&ftrace_max_lock); |
ab46428c | 2196 | for_each_tracing_cpu(cpu) { |
36dfe925 IM |
2197 | /* |
2198 | * Increase/decrease the disabled counter if we are | |
2199 | * about to flip a bit in the cpumask: | |
2200 | */ | |
9e01c1b7 RR |
2201 | if (cpumask_test_cpu(cpu, tracing_cpumask) && |
2202 | !cpumask_test_cpu(cpu, tracing_cpumask_new)) { | |
36dfe925 IM |
2203 | atomic_inc(&global_trace.data[cpu]->disabled); |
2204 | } | |
9e01c1b7 RR |
2205 | if (!cpumask_test_cpu(cpu, tracing_cpumask) && |
2206 | cpumask_test_cpu(cpu, tracing_cpumask_new)) { | |
36dfe925 IM |
2207 | atomic_dec(&global_trace.data[cpu]->disabled); |
2208 | } | |
2209 | } | |
92205c23 | 2210 | __raw_spin_unlock(&ftrace_max_lock); |
a5e25883 | 2211 | local_irq_enable(); |
36dfe925 | 2212 | |
9e01c1b7 | 2213 | cpumask_copy(tracing_cpumask, tracing_cpumask_new); |
36dfe925 IM |
2214 | |
2215 | mutex_unlock(&tracing_cpumask_update_lock); | |
9e01c1b7 | 2216 | free_cpumask_var(tracing_cpumask_new); |
c7078de1 IM |
2217 | |
2218 | return count; | |
36dfe925 IM |
2219 | |
2220 | err_unlock: | |
2221 | mutex_unlock(&tracing_cpumask_update_lock); | |
9e01c1b7 | 2222 | free_cpumask_var(tracing_cpumask); |
36dfe925 IM |
2223 | |
2224 | return err; | |
c7078de1 IM |
2225 | } |
2226 | ||
5e2336a0 | 2227 | static const struct file_operations tracing_cpumask_fops = { |
c7078de1 IM |
2228 | .open = tracing_open_generic, |
2229 | .read = tracing_cpumask_read, | |
2230 | .write = tracing_cpumask_write, | |
bc0c38d1 SR |
2231 | }; |
2232 | ||
2233 | static ssize_t | |
ee6bce52 | 2234 | tracing_trace_options_read(struct file *filp, char __user *ubuf, |
bc0c38d1 SR |
2235 | size_t cnt, loff_t *ppos) |
2236 | { | |
d8e83d26 SR |
2237 | struct tracer_opt *trace_opts; |
2238 | u32 tracer_flags; | |
2239 | int len = 0; | |
bc0c38d1 SR |
2240 | char *buf; |
2241 | int r = 0; | |
d8e83d26 | 2242 | int i; |
adf9f195 | 2243 | |
bc0c38d1 | 2244 | |
c3706f00 | 2245 | /* calculate max size */ |
bc0c38d1 SR |
2246 | for (i = 0; trace_options[i]; i++) { |
2247 | len += strlen(trace_options[i]); | |
5c6a3ae1 | 2248 | len += 3; /* "no" and newline */ |
bc0c38d1 SR |
2249 | } |
2250 | ||
d8e83d26 SR |
2251 | mutex_lock(&trace_types_lock); |
2252 | tracer_flags = current_trace->flags->val; | |
2253 | trace_opts = current_trace->flags->opts; | |
2254 | ||
adf9f195 FW |
2255 | /* |
2256 | * Increase the size with names of options specific | |
2257 | * of the current tracer. | |
2258 | */ | |
2259 | for (i = 0; trace_opts[i].name; i++) { | |
2260 | len += strlen(trace_opts[i].name); | |
5c6a3ae1 | 2261 | len += 3; /* "no" and newline */ |
adf9f195 FW |
2262 | } |
2263 | ||
bc0c38d1 SR |
2264 | /* +2 for \n and \0 */ |
2265 | buf = kmalloc(len + 2, GFP_KERNEL); | |
d8e83d26 SR |
2266 | if (!buf) { |
2267 | mutex_unlock(&trace_types_lock); | |
bc0c38d1 | 2268 | return -ENOMEM; |
d8e83d26 | 2269 | } |
bc0c38d1 SR |
2270 | |
2271 | for (i = 0; trace_options[i]; i++) { | |
2272 | if (trace_flags & (1 << i)) | |
5c6a3ae1 | 2273 | r += sprintf(buf + r, "%s\n", trace_options[i]); |
bc0c38d1 | 2274 | else |
5c6a3ae1 | 2275 | r += sprintf(buf + r, "no%s\n", trace_options[i]); |
bc0c38d1 SR |
2276 | } |
2277 | ||
adf9f195 FW |
2278 | for (i = 0; trace_opts[i].name; i++) { |
2279 | if (tracer_flags & trace_opts[i].bit) | |
5c6a3ae1 | 2280 | r += sprintf(buf + r, "%s\n", |
adf9f195 FW |
2281 | trace_opts[i].name); |
2282 | else | |
5c6a3ae1 | 2283 | r += sprintf(buf + r, "no%s\n", |
adf9f195 FW |
2284 | trace_opts[i].name); |
2285 | } | |
d8e83d26 | 2286 | mutex_unlock(&trace_types_lock); |
adf9f195 | 2287 | |
bc0c38d1 SR |
2288 | WARN_ON(r >= len + 2); |
2289 | ||
36dfe925 | 2290 | r = simple_read_from_buffer(ubuf, cnt, ppos, buf, r); |
bc0c38d1 SR |
2291 | |
2292 | kfree(buf); | |
bc0c38d1 SR |
2293 | return r; |
2294 | } | |
2295 | ||
adf9f195 FW |
2296 | /* Try to assign a tracer specific option */ |
2297 | static int set_tracer_option(struct tracer *trace, char *cmp, int neg) | |
2298 | { | |
2299 | struct tracer_flags *trace_flags = trace->flags; | |
2300 | struct tracer_opt *opts = NULL; | |
2301 | int ret = 0, i = 0; | |
2302 | int len; | |
2303 | ||
2304 | for (i = 0; trace_flags->opts[i].name; i++) { | |
2305 | opts = &trace_flags->opts[i]; | |
2306 | len = strlen(opts->name); | |
2307 | ||
2308 | if (strncmp(cmp, opts->name, len) == 0) { | |
2309 | ret = trace->set_flag(trace_flags->val, | |
2310 | opts->bit, !neg); | |
2311 | break; | |
2312 | } | |
2313 | } | |
2314 | /* Not found */ | |
2315 | if (!trace_flags->opts[i].name) | |
2316 | return -EINVAL; | |
2317 | ||
2318 | /* Refused to handle */ | |
2319 | if (ret) | |
2320 | return ret; | |
2321 | ||
2322 | if (neg) | |
2323 | trace_flags->val &= ~opts->bit; | |
2324 | else | |
2325 | trace_flags->val |= opts->bit; | |
2326 | ||
2327 | return 0; | |
2328 | } | |
2329 | ||
af4617bd SR |
2330 | static void set_tracer_flags(unsigned int mask, int enabled) |
2331 | { | |
2332 | /* do nothing if flag is already set */ | |
2333 | if (!!(trace_flags & mask) == !!enabled) | |
2334 | return; | |
2335 | ||
2336 | if (enabled) | |
2337 | trace_flags |= mask; | |
2338 | else | |
2339 | trace_flags &= ~mask; | |
2340 | ||
2341 | if (mask == TRACE_ITER_GLOBAL_CLK) { | |
2342 | u64 (*func)(void); | |
2343 | ||
2344 | if (enabled) | |
2345 | func = trace_clock_global; | |
2346 | else | |
2347 | func = trace_clock_local; | |
2348 | ||
2349 | mutex_lock(&trace_types_lock); | |
2350 | ring_buffer_set_clock(global_trace.buffer, func); | |
2351 | ||
2352 | if (max_tr.buffer) | |
2353 | ring_buffer_set_clock(max_tr.buffer, func); | |
2354 | mutex_unlock(&trace_types_lock); | |
2355 | } | |
2356 | } | |
2357 | ||
bc0c38d1 | 2358 | static ssize_t |
ee6bce52 | 2359 | tracing_trace_options_write(struct file *filp, const char __user *ubuf, |
bc0c38d1 SR |
2360 | size_t cnt, loff_t *ppos) |
2361 | { | |
2362 | char buf[64]; | |
2363 | char *cmp = buf; | |
2364 | int neg = 0; | |
adf9f195 | 2365 | int ret; |
bc0c38d1 SR |
2366 | int i; |
2367 | ||
cffae437 SR |
2368 | if (cnt >= sizeof(buf)) |
2369 | return -EINVAL; | |
bc0c38d1 SR |
2370 | |
2371 | if (copy_from_user(&buf, ubuf, cnt)) | |
2372 | return -EFAULT; | |
2373 | ||
2374 | buf[cnt] = 0; | |
2375 | ||
2376 | if (strncmp(buf, "no", 2) == 0) { | |
2377 | neg = 1; | |
2378 | cmp += 2; | |
2379 | } | |
2380 | ||
2381 | for (i = 0; trace_options[i]; i++) { | |
2382 | int len = strlen(trace_options[i]); | |
2383 | ||
2384 | if (strncmp(cmp, trace_options[i], len) == 0) { | |
af4617bd | 2385 | set_tracer_flags(1 << i, !neg); |
bc0c38d1 SR |
2386 | break; |
2387 | } | |
2388 | } | |
adf9f195 FW |
2389 | |
2390 | /* If no option could be set, test the specific tracer options */ | |
2391 | if (!trace_options[i]) { | |
d8e83d26 | 2392 | mutex_lock(&trace_types_lock); |
adf9f195 | 2393 | ret = set_tracer_option(current_trace, cmp, neg); |
d8e83d26 | 2394 | mutex_unlock(&trace_types_lock); |
adf9f195 FW |
2395 | if (ret) |
2396 | return ret; | |
2397 | } | |
bc0c38d1 SR |
2398 | |
2399 | filp->f_pos += cnt; | |
2400 | ||
2401 | return cnt; | |
2402 | } | |
2403 | ||
5e2336a0 | 2404 | static const struct file_operations tracing_iter_fops = { |
c7078de1 | 2405 | .open = tracing_open_generic, |
ee6bce52 SR |
2406 | .read = tracing_trace_options_read, |
2407 | .write = tracing_trace_options_write, | |
bc0c38d1 SR |
2408 | }; |
2409 | ||
7bd2f24c IM |
2410 | static const char readme_msg[] = |
2411 | "tracing mini-HOWTO:\n\n" | |
2412 | "# mkdir /debug\n" | |
2413 | "# mount -t debugfs nodev /debug\n\n" | |
2414 | "# cat /debug/tracing/available_tracers\n" | |
bc2b6871 | 2415 | "wakeup preemptirqsoff preemptoff irqsoff function sched_switch nop\n\n" |
7bd2f24c | 2416 | "# cat /debug/tracing/current_tracer\n" |
bc2b6871 | 2417 | "nop\n" |
7bd2f24c IM |
2418 | "# echo sched_switch > /debug/tracing/current_tracer\n" |
2419 | "# cat /debug/tracing/current_tracer\n" | |
2420 | "sched_switch\n" | |
ee6bce52 | 2421 | "# cat /debug/tracing/trace_options\n" |
7bd2f24c | 2422 | "noprint-parent nosym-offset nosym-addr noverbose\n" |
ee6bce52 | 2423 | "# echo print-parent > /debug/tracing/trace_options\n" |
7bd2f24c IM |
2424 | "# echo 1 > /debug/tracing/tracing_enabled\n" |
2425 | "# cat /debug/tracing/trace > /tmp/trace.txt\n" | |
2426 | "echo 0 > /debug/tracing/tracing_enabled\n" | |
2427 | ; | |
2428 | ||
2429 | static ssize_t | |
2430 | tracing_readme_read(struct file *filp, char __user *ubuf, | |
2431 | size_t cnt, loff_t *ppos) | |
2432 | { | |
2433 | return simple_read_from_buffer(ubuf, cnt, ppos, | |
2434 | readme_msg, strlen(readme_msg)); | |
2435 | } | |
2436 | ||
5e2336a0 | 2437 | static const struct file_operations tracing_readme_fops = { |
c7078de1 IM |
2438 | .open = tracing_open_generic, |
2439 | .read = tracing_readme_read, | |
7bd2f24c IM |
2440 | }; |
2441 | ||
69abe6a5 AP |
2442 | static ssize_t |
2443 | tracing_saved_cmdlines_read(struct file *file, char __user *ubuf, | |
2444 | size_t cnt, loff_t *ppos) | |
2445 | { | |
2446 | char *buf_comm; | |
2447 | char *file_buf; | |
2448 | char *buf; | |
2449 | int len = 0; | |
2450 | int pid; | |
2451 | int i; | |
2452 | ||
2453 | file_buf = kmalloc(SAVED_CMDLINES*(16+TASK_COMM_LEN), GFP_KERNEL); | |
2454 | if (!file_buf) | |
2455 | return -ENOMEM; | |
2456 | ||
2457 | buf_comm = kmalloc(TASK_COMM_LEN, GFP_KERNEL); | |
2458 | if (!buf_comm) { | |
2459 | kfree(file_buf); | |
2460 | return -ENOMEM; | |
2461 | } | |
2462 | ||
2463 | buf = file_buf; | |
2464 | ||
2465 | for (i = 0; i < SAVED_CMDLINES; i++) { | |
2466 | int r; | |
2467 | ||
2468 | pid = map_cmdline_to_pid[i]; | |
2469 | if (pid == -1 || pid == NO_CMDLINE_MAP) | |
2470 | continue; | |
2471 | ||
2472 | trace_find_cmdline(pid, buf_comm); | |
2473 | r = sprintf(buf, "%d %s\n", pid, buf_comm); | |
2474 | buf += r; | |
2475 | len += r; | |
2476 | } | |
2477 | ||
2478 | len = simple_read_from_buffer(ubuf, cnt, ppos, | |
2479 | file_buf, len); | |
2480 | ||
2481 | kfree(file_buf); | |
2482 | kfree(buf_comm); | |
2483 | ||
2484 | return len; | |
2485 | } | |
2486 | ||
2487 | static const struct file_operations tracing_saved_cmdlines_fops = { | |
2488 | .open = tracing_open_generic, | |
2489 | .read = tracing_saved_cmdlines_read, | |
2490 | }; | |
2491 | ||
bc0c38d1 SR |
2492 | static ssize_t |
2493 | tracing_ctrl_read(struct file *filp, char __user *ubuf, | |
2494 | size_t cnt, loff_t *ppos) | |
2495 | { | |
bc0c38d1 SR |
2496 | char buf[64]; |
2497 | int r; | |
2498 | ||
9036990d | 2499 | r = sprintf(buf, "%u\n", tracer_enabled); |
4e3c3333 | 2500 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, r); |
bc0c38d1 SR |
2501 | } |
2502 | ||
2503 | static ssize_t | |
2504 | tracing_ctrl_write(struct file *filp, const char __user *ubuf, | |
2505 | size_t cnt, loff_t *ppos) | |
2506 | { | |
2507 | struct trace_array *tr = filp->private_data; | |
bc0c38d1 | 2508 | char buf[64]; |
5e39841c | 2509 | unsigned long val; |
c6caeeb1 | 2510 | int ret; |
bc0c38d1 | 2511 | |
cffae437 SR |
2512 | if (cnt >= sizeof(buf)) |
2513 | return -EINVAL; | |
bc0c38d1 SR |
2514 | |
2515 | if (copy_from_user(&buf, ubuf, cnt)) | |
2516 | return -EFAULT; | |
2517 | ||
2518 | buf[cnt] = 0; | |
2519 | ||
c6caeeb1 SR |
2520 | ret = strict_strtoul(buf, 10, &val); |
2521 | if (ret < 0) | |
2522 | return ret; | |
bc0c38d1 SR |
2523 | |
2524 | val = !!val; | |
2525 | ||
2526 | mutex_lock(&trace_types_lock); | |
9036990d SR |
2527 | if (tracer_enabled ^ val) { |
2528 | if (val) { | |
bc0c38d1 | 2529 | tracer_enabled = 1; |
9036990d SR |
2530 | if (current_trace->start) |
2531 | current_trace->start(tr); | |
2532 | tracing_start(); | |
2533 | } else { | |
bc0c38d1 | 2534 | tracer_enabled = 0; |
9036990d SR |
2535 | tracing_stop(); |
2536 | if (current_trace->stop) | |
2537 | current_trace->stop(tr); | |
2538 | } | |
bc0c38d1 SR |
2539 | } |
2540 | mutex_unlock(&trace_types_lock); | |
2541 | ||
2542 | filp->f_pos += cnt; | |
2543 | ||
2544 | return cnt; | |
2545 | } | |
2546 | ||
2547 | static ssize_t | |
2548 | tracing_set_trace_read(struct file *filp, char __user *ubuf, | |
2549 | size_t cnt, loff_t *ppos) | |
2550 | { | |
2551 | char buf[max_tracer_type_len+2]; | |
2552 | int r; | |
2553 | ||
2554 | mutex_lock(&trace_types_lock); | |
2555 | if (current_trace) | |
2556 | r = sprintf(buf, "%s\n", current_trace->name); | |
2557 | else | |
2558 | r = sprintf(buf, "\n"); | |
2559 | mutex_unlock(&trace_types_lock); | |
2560 | ||
4bf39a94 | 2561 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, r); |
bc0c38d1 SR |
2562 | } |
2563 | ||
b6f11df2 ACM |
2564 | int tracer_init(struct tracer *t, struct trace_array *tr) |
2565 | { | |
2566 | tracing_reset_online_cpus(tr); | |
2567 | return t->init(tr); | |
2568 | } | |
2569 | ||
73c5162a SR |
2570 | static int tracing_resize_ring_buffer(unsigned long size) |
2571 | { | |
2572 | int ret; | |
2573 | ||
2574 | /* | |
2575 | * If kernel or user changes the size of the ring buffer | |
a123c52b SR |
2576 | * we use the size that was given, and we can forget about |
2577 | * expanding it later. | |
73c5162a SR |
2578 | */ |
2579 | ring_buffer_expanded = 1; | |
2580 | ||
2581 | ret = ring_buffer_resize(global_trace.buffer, size); | |
2582 | if (ret < 0) | |
2583 | return ret; | |
2584 | ||
2585 | ret = ring_buffer_resize(max_tr.buffer, size); | |
2586 | if (ret < 0) { | |
2587 | int r; | |
2588 | ||
2589 | r = ring_buffer_resize(global_trace.buffer, | |
2590 | global_trace.entries); | |
2591 | if (r < 0) { | |
a123c52b SR |
2592 | /* |
2593 | * AARGH! We are left with different | |
2594 | * size max buffer!!!! | |
2595 | * The max buffer is our "snapshot" buffer. | |
2596 | * When a tracer needs a snapshot (one of the | |
2597 | * latency tracers), it swaps the max buffer | |
2598 | * with the saved snap shot. We succeeded to | |
2599 | * update the size of the main buffer, but failed to | |
2600 | * update the size of the max buffer. But when we tried | |
2601 | * to reset the main buffer to the original size, we | |
2602 | * failed there too. This is very unlikely to | |
2603 | * happen, but if it does, warn and kill all | |
2604 | * tracing. | |
2605 | */ | |
73c5162a SR |
2606 | WARN_ON(1); |
2607 | tracing_disabled = 1; | |
2608 | } | |
2609 | return ret; | |
2610 | } | |
2611 | ||
2612 | global_trace.entries = size; | |
2613 | ||
2614 | return ret; | |
2615 | } | |
2616 | ||
1852fcce SR |
2617 | /** |
2618 | * tracing_update_buffers - used by tracing facility to expand ring buffers | |
2619 | * | |
2620 | * To save on memory when the tracing is never used on a system with it | |
2621 | * configured in. The ring buffers are set to a minimum size. But once | |
2622 | * a user starts to use the tracing facility, then they need to grow | |
2623 | * to their default size. | |
2624 | * | |
2625 | * This function is to be called when a tracer is about to be used. | |
2626 | */ | |
2627 | int tracing_update_buffers(void) | |
2628 | { | |
2629 | int ret = 0; | |
2630 | ||
1027fcb2 | 2631 | mutex_lock(&trace_types_lock); |
1852fcce SR |
2632 | if (!ring_buffer_expanded) |
2633 | ret = tracing_resize_ring_buffer(trace_buf_size); | |
1027fcb2 | 2634 | mutex_unlock(&trace_types_lock); |
1852fcce SR |
2635 | |
2636 | return ret; | |
2637 | } | |
2638 | ||
577b785f SR |
2639 | struct trace_option_dentry; |
2640 | ||
2641 | static struct trace_option_dentry * | |
2642 | create_trace_option_files(struct tracer *tracer); | |
2643 | ||
2644 | static void | |
2645 | destroy_trace_option_files(struct trace_option_dentry *topts); | |
2646 | ||
b2821ae6 | 2647 | static int tracing_set_tracer(const char *buf) |
bc0c38d1 | 2648 | { |
577b785f | 2649 | static struct trace_option_dentry *topts; |
bc0c38d1 SR |
2650 | struct trace_array *tr = &global_trace; |
2651 | struct tracer *t; | |
d9e54076 | 2652 | int ret = 0; |
bc0c38d1 | 2653 | |
1027fcb2 SR |
2654 | mutex_lock(&trace_types_lock); |
2655 | ||
73c5162a SR |
2656 | if (!ring_buffer_expanded) { |
2657 | ret = tracing_resize_ring_buffer(trace_buf_size); | |
2658 | if (ret < 0) | |
59f586db | 2659 | goto out; |
73c5162a SR |
2660 | ret = 0; |
2661 | } | |
2662 | ||
bc0c38d1 SR |
2663 | for (t = trace_types; t; t = t->next) { |
2664 | if (strcmp(t->name, buf) == 0) | |
2665 | break; | |
2666 | } | |
c2931e05 FW |
2667 | if (!t) { |
2668 | ret = -EINVAL; | |
2669 | goto out; | |
2670 | } | |
2671 | if (t == current_trace) | |
bc0c38d1 SR |
2672 | goto out; |
2673 | ||
9f029e83 | 2674 | trace_branch_disable(); |
bc0c38d1 SR |
2675 | if (current_trace && current_trace->reset) |
2676 | current_trace->reset(tr); | |
2677 | ||
577b785f SR |
2678 | destroy_trace_option_files(topts); |
2679 | ||
bc0c38d1 | 2680 | current_trace = t; |
577b785f SR |
2681 | |
2682 | topts = create_trace_option_files(current_trace); | |
2683 | ||
1c80025a | 2684 | if (t->init) { |
b6f11df2 | 2685 | ret = tracer_init(t, tr); |
1c80025a FW |
2686 | if (ret) |
2687 | goto out; | |
2688 | } | |
bc0c38d1 | 2689 | |
9f029e83 | 2690 | trace_branch_enable(tr); |
bc0c38d1 SR |
2691 | out: |
2692 | mutex_unlock(&trace_types_lock); | |
2693 | ||
d9e54076 PZ |
2694 | return ret; |
2695 | } | |
2696 | ||
2697 | static ssize_t | |
2698 | tracing_set_trace_write(struct file *filp, const char __user *ubuf, | |
2699 | size_t cnt, loff_t *ppos) | |
2700 | { | |
2701 | char buf[max_tracer_type_len+1]; | |
2702 | int i; | |
2703 | size_t ret; | |
e6e7a65a FW |
2704 | int err; |
2705 | ||
2706 | ret = cnt; | |
d9e54076 PZ |
2707 | |
2708 | if (cnt > max_tracer_type_len) | |
2709 | cnt = max_tracer_type_len; | |
2710 | ||
2711 | if (copy_from_user(&buf, ubuf, cnt)) | |
2712 | return -EFAULT; | |
2713 | ||
2714 | buf[cnt] = 0; | |
2715 | ||
2716 | /* strip ending whitespace. */ | |
2717 | for (i = cnt - 1; i > 0 && isspace(buf[i]); i--) | |
2718 | buf[i] = 0; | |
2719 | ||
e6e7a65a FW |
2720 | err = tracing_set_tracer(buf); |
2721 | if (err) | |
2722 | return err; | |
d9e54076 | 2723 | |
e6e7a65a | 2724 | filp->f_pos += ret; |
bc0c38d1 | 2725 | |
c2931e05 | 2726 | return ret; |
bc0c38d1 SR |
2727 | } |
2728 | ||
2729 | static ssize_t | |
2730 | tracing_max_lat_read(struct file *filp, char __user *ubuf, | |
2731 | size_t cnt, loff_t *ppos) | |
2732 | { | |
2733 | unsigned long *ptr = filp->private_data; | |
2734 | char buf[64]; | |
2735 | int r; | |
2736 | ||
cffae437 | 2737 | r = snprintf(buf, sizeof(buf), "%ld\n", |
bc0c38d1 | 2738 | *ptr == (unsigned long)-1 ? -1 : nsecs_to_usecs(*ptr)); |
cffae437 SR |
2739 | if (r > sizeof(buf)) |
2740 | r = sizeof(buf); | |
4bf39a94 | 2741 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, r); |
bc0c38d1 SR |
2742 | } |
2743 | ||
2744 | static ssize_t | |
2745 | tracing_max_lat_write(struct file *filp, const char __user *ubuf, | |
2746 | size_t cnt, loff_t *ppos) | |
2747 | { | |
5e39841c | 2748 | unsigned long *ptr = filp->private_data; |
bc0c38d1 | 2749 | char buf[64]; |
5e39841c | 2750 | unsigned long val; |
c6caeeb1 | 2751 | int ret; |
bc0c38d1 | 2752 | |
cffae437 SR |
2753 | if (cnt >= sizeof(buf)) |
2754 | return -EINVAL; | |
bc0c38d1 SR |
2755 | |
2756 | if (copy_from_user(&buf, ubuf, cnt)) | |
2757 | return -EFAULT; | |
2758 | ||
2759 | buf[cnt] = 0; | |
2760 | ||
c6caeeb1 SR |
2761 | ret = strict_strtoul(buf, 10, &val); |
2762 | if (ret < 0) | |
2763 | return ret; | |
bc0c38d1 SR |
2764 | |
2765 | *ptr = val * 1000; | |
2766 | ||
2767 | return cnt; | |
2768 | } | |
2769 | ||
b3806b43 SR |
2770 | static int tracing_open_pipe(struct inode *inode, struct file *filp) |
2771 | { | |
b04cc6b1 | 2772 | long cpu_file = (long) inode->i_private; |
b3806b43 | 2773 | struct trace_iterator *iter; |
b04cc6b1 | 2774 | int ret = 0; |
b3806b43 SR |
2775 | |
2776 | if (tracing_disabled) | |
2777 | return -ENODEV; | |
2778 | ||
b04cc6b1 FW |
2779 | mutex_lock(&trace_types_lock); |
2780 | ||
2781 | /* We only allow one reader per cpu */ | |
2782 | if (cpu_file == TRACE_PIPE_ALL_CPU) { | |
2783 | if (!cpumask_empty(tracing_reader_cpumask)) { | |
2784 | ret = -EBUSY; | |
2785 | goto out; | |
2786 | } | |
2787 | cpumask_setall(tracing_reader_cpumask); | |
2788 | } else { | |
2789 | if (!cpumask_test_cpu(cpu_file, tracing_reader_cpumask)) | |
2790 | cpumask_set_cpu(cpu_file, tracing_reader_cpumask); | |
2791 | else { | |
2792 | ret = -EBUSY; | |
2793 | goto out; | |
2794 | } | |
b3806b43 SR |
2795 | } |
2796 | ||
2797 | /* create a buffer to store the information to pass to userspace */ | |
2798 | iter = kzalloc(sizeof(*iter), GFP_KERNEL); | |
b04cc6b1 FW |
2799 | if (!iter) { |
2800 | ret = -ENOMEM; | |
2801 | goto out; | |
2802 | } | |
b3806b43 | 2803 | |
d7350c3f FW |
2804 | /* |
2805 | * We make a copy of the current tracer to avoid concurrent | |
2806 | * changes on it while we are reading. | |
2807 | */ | |
2808 | iter->trace = kmalloc(sizeof(*iter->trace), GFP_KERNEL); | |
2809 | if (!iter->trace) { | |
2810 | ret = -ENOMEM; | |
2811 | goto fail; | |
2812 | } | |
2813 | if (current_trace) | |
2814 | *iter->trace = *current_trace; | |
2815 | ||
4462344e | 2816 | if (!alloc_cpumask_var(&iter->started, GFP_KERNEL)) { |
b04cc6b1 | 2817 | ret = -ENOMEM; |
d7350c3f | 2818 | goto fail; |
4462344e RR |
2819 | } |
2820 | ||
a309720c | 2821 | /* trace pipe does not show start of buffer */ |
4462344e | 2822 | cpumask_setall(iter->started); |
a309720c | 2823 | |
b04cc6b1 | 2824 | iter->cpu_file = cpu_file; |
b3806b43 | 2825 | iter->tr = &global_trace; |
d7350c3f | 2826 | mutex_init(&iter->mutex); |
b3806b43 SR |
2827 | filp->private_data = iter; |
2828 | ||
107bad8b SR |
2829 | if (iter->trace->pipe_open) |
2830 | iter->trace->pipe_open(iter); | |
107bad8b | 2831 | |
b04cc6b1 FW |
2832 | out: |
2833 | mutex_unlock(&trace_types_lock); | |
2834 | return ret; | |
d7350c3f FW |
2835 | |
2836 | fail: | |
2837 | kfree(iter->trace); | |
2838 | kfree(iter); | |
2839 | mutex_unlock(&trace_types_lock); | |
2840 | return ret; | |
b3806b43 SR |
2841 | } |
2842 | ||
2843 | static int tracing_release_pipe(struct inode *inode, struct file *file) | |
2844 | { | |
2845 | struct trace_iterator *iter = file->private_data; | |
2846 | ||
b04cc6b1 FW |
2847 | mutex_lock(&trace_types_lock); |
2848 | ||
2849 | if (iter->cpu_file == TRACE_PIPE_ALL_CPU) | |
2850 | cpumask_clear(tracing_reader_cpumask); | |
2851 | else | |
2852 | cpumask_clear_cpu(iter->cpu_file, tracing_reader_cpumask); | |
2853 | ||
2854 | mutex_unlock(&trace_types_lock); | |
2855 | ||
4462344e | 2856 | free_cpumask_var(iter->started); |
d7350c3f FW |
2857 | mutex_destroy(&iter->mutex); |
2858 | kfree(iter->trace); | |
b3806b43 | 2859 | kfree(iter); |
b3806b43 SR |
2860 | |
2861 | return 0; | |
2862 | } | |
2863 | ||
2a2cc8f7 SSP |
2864 | static unsigned int |
2865 | tracing_poll_pipe(struct file *filp, poll_table *poll_table) | |
2866 | { | |
2867 | struct trace_iterator *iter = filp->private_data; | |
2868 | ||
2869 | if (trace_flags & TRACE_ITER_BLOCK) { | |
2870 | /* | |
2871 | * Always select as readable when in blocking mode | |
2872 | */ | |
2873 | return POLLIN | POLLRDNORM; | |
afc2abc0 | 2874 | } else { |
2a2cc8f7 SSP |
2875 | if (!trace_empty(iter)) |
2876 | return POLLIN | POLLRDNORM; | |
2877 | poll_wait(filp, &trace_wait, poll_table); | |
2878 | if (!trace_empty(iter)) | |
2879 | return POLLIN | POLLRDNORM; | |
2880 | ||
2881 | return 0; | |
2882 | } | |
2883 | } | |
2884 | ||
6eaaa5d5 FW |
2885 | |
2886 | void default_wait_pipe(struct trace_iterator *iter) | |
2887 | { | |
2888 | DEFINE_WAIT(wait); | |
2889 | ||
2890 | prepare_to_wait(&trace_wait, &wait, TASK_INTERRUPTIBLE); | |
2891 | ||
2892 | if (trace_empty(iter)) | |
2893 | schedule(); | |
2894 | ||
2895 | finish_wait(&trace_wait, &wait); | |
2896 | } | |
2897 | ||
2898 | /* | |
2899 | * This is a make-shift waitqueue. | |
2900 | * A tracer might use this callback on some rare cases: | |
2901 | * | |
2902 | * 1) the current tracer might hold the runqueue lock when it wakes up | |
2903 | * a reader, hence a deadlock (sched, function, and function graph tracers) | |
2904 | * 2) the function tracers, trace all functions, we don't want | |
2905 | * the overhead of calling wake_up and friends | |
2906 | * (and tracing them too) | |
2907 | * | |
2908 | * Anyway, this is really very primitive wakeup. | |
2909 | */ | |
2910 | void poll_wait_pipe(struct trace_iterator *iter) | |
2911 | { | |
2912 | set_current_state(TASK_INTERRUPTIBLE); | |
2913 | /* sleep for 100 msecs, and try again. */ | |
2914 | schedule_timeout(HZ / 10); | |
2915 | } | |
2916 | ||
ff98781b EGM |
2917 | /* Must be called with trace_types_lock mutex held. */ |
2918 | static int tracing_wait_pipe(struct file *filp) | |
b3806b43 SR |
2919 | { |
2920 | struct trace_iterator *iter = filp->private_data; | |
b3806b43 | 2921 | |
b3806b43 | 2922 | while (trace_empty(iter)) { |
2dc8f095 | 2923 | |
107bad8b | 2924 | if ((filp->f_flags & O_NONBLOCK)) { |
ff98781b | 2925 | return -EAGAIN; |
107bad8b | 2926 | } |
2dc8f095 | 2927 | |
d7350c3f | 2928 | mutex_unlock(&iter->mutex); |
107bad8b | 2929 | |
6eaaa5d5 | 2930 | iter->trace->wait_pipe(iter); |
b3806b43 | 2931 | |
d7350c3f | 2932 | mutex_lock(&iter->mutex); |
107bad8b | 2933 | |
6eaaa5d5 | 2934 | if (signal_pending(current)) |
ff98781b | 2935 | return -EINTR; |
b3806b43 SR |
2936 | |
2937 | /* | |
2938 | * We block until we read something and tracing is disabled. | |
2939 | * We still block if tracing is disabled, but we have never | |
2940 | * read anything. This allows a user to cat this file, and | |
2941 | * then enable tracing. But after we have read something, | |
2942 | * we give an EOF when tracing is again disabled. | |
2943 | * | |
2944 | * iter->pos will be 0 if we haven't read anything. | |
2945 | */ | |
2946 | if (!tracer_enabled && iter->pos) | |
2947 | break; | |
b3806b43 SR |
2948 | } |
2949 | ||
ff98781b EGM |
2950 | return 1; |
2951 | } | |
2952 | ||
2953 | /* | |
2954 | * Consumer reader. | |
2955 | */ | |
2956 | static ssize_t | |
2957 | tracing_read_pipe(struct file *filp, char __user *ubuf, | |
2958 | size_t cnt, loff_t *ppos) | |
2959 | { | |
2960 | struct trace_iterator *iter = filp->private_data; | |
d7350c3f | 2961 | static struct tracer *old_tracer; |
ff98781b EGM |
2962 | ssize_t sret; |
2963 | ||
2964 | /* return any leftover data */ | |
2965 | sret = trace_seq_to_user(&iter->seq, ubuf, cnt); | |
2966 | if (sret != -EBUSY) | |
2967 | return sret; | |
2968 | ||
f9520750 | 2969 | trace_seq_init(&iter->seq); |
ff98781b | 2970 | |
d7350c3f | 2971 | /* copy the tracer to avoid using a global lock all around */ |
ff98781b | 2972 | mutex_lock(&trace_types_lock); |
d7350c3f FW |
2973 | if (unlikely(old_tracer != current_trace && current_trace)) { |
2974 | old_tracer = current_trace; | |
2975 | *iter->trace = *current_trace; | |
2976 | } | |
2977 | mutex_unlock(&trace_types_lock); | |
2978 | ||
2979 | /* | |
2980 | * Avoid more than one consumer on a single file descriptor | |
2981 | * This is just a matter of traces coherency, the ring buffer itself | |
2982 | * is protected. | |
2983 | */ | |
2984 | mutex_lock(&iter->mutex); | |
ff98781b EGM |
2985 | if (iter->trace->read) { |
2986 | sret = iter->trace->read(iter, filp, ubuf, cnt, ppos); | |
2987 | if (sret) | |
2988 | goto out; | |
2989 | } | |
2990 | ||
2991 | waitagain: | |
2992 | sret = tracing_wait_pipe(filp); | |
2993 | if (sret <= 0) | |
2994 | goto out; | |
2995 | ||
b3806b43 | 2996 | /* stop when tracing is finished */ |
ff98781b EGM |
2997 | if (trace_empty(iter)) { |
2998 | sret = 0; | |
107bad8b | 2999 | goto out; |
ff98781b | 3000 | } |
b3806b43 SR |
3001 | |
3002 | if (cnt >= PAGE_SIZE) | |
3003 | cnt = PAGE_SIZE - 1; | |
3004 | ||
53d0aa77 | 3005 | /* reset all but tr, trace, and overruns */ |
53d0aa77 SR |
3006 | memset(&iter->seq, 0, |
3007 | sizeof(struct trace_iterator) - | |
3008 | offsetof(struct trace_iterator, seq)); | |
4823ed7e | 3009 | iter->pos = -1; |
b3806b43 | 3010 | |
088b1e42 | 3011 | while (find_next_entry_inc(iter) != NULL) { |
2c4f035f | 3012 | enum print_line_t ret; |
088b1e42 SR |
3013 | int len = iter->seq.len; |
3014 | ||
f9896bf3 | 3015 | ret = print_trace_line(iter); |
2c4f035f | 3016 | if (ret == TRACE_TYPE_PARTIAL_LINE) { |
088b1e42 SR |
3017 | /* don't print partial lines */ |
3018 | iter->seq.len = len; | |
b3806b43 | 3019 | break; |
088b1e42 | 3020 | } |
b91facc3 FW |
3021 | if (ret != TRACE_TYPE_NO_CONSUME) |
3022 | trace_consume(iter); | |
b3806b43 SR |
3023 | |
3024 | if (iter->seq.len >= cnt) | |
3025 | break; | |
b3806b43 SR |
3026 | } |
3027 | ||
b3806b43 | 3028 | /* Now copy what we have to the user */ |
6c6c2796 PP |
3029 | sret = trace_seq_to_user(&iter->seq, ubuf, cnt); |
3030 | if (iter->seq.readpos >= iter->seq.len) | |
f9520750 | 3031 | trace_seq_init(&iter->seq); |
9ff4b974 PP |
3032 | |
3033 | /* | |
3034 | * If there was nothing to send to user, inspite of consuming trace | |
3035 | * entries, go back to wait for more entries. | |
3036 | */ | |
6c6c2796 | 3037 | if (sret == -EBUSY) |
9ff4b974 | 3038 | goto waitagain; |
b3806b43 | 3039 | |
107bad8b | 3040 | out: |
d7350c3f | 3041 | mutex_unlock(&iter->mutex); |
107bad8b | 3042 | |
6c6c2796 | 3043 | return sret; |
b3806b43 SR |
3044 | } |
3045 | ||
3c56819b EGM |
3046 | static void tracing_pipe_buf_release(struct pipe_inode_info *pipe, |
3047 | struct pipe_buffer *buf) | |
3048 | { | |
3049 | __free_page(buf->page); | |
3050 | } | |
3051 | ||
3052 | static void tracing_spd_release_pipe(struct splice_pipe_desc *spd, | |
3053 | unsigned int idx) | |
3054 | { | |
3055 | __free_page(spd->pages[idx]); | |
3056 | } | |
3057 | ||
3058 | static struct pipe_buf_operations tracing_pipe_buf_ops = { | |
34cd4998 SR |
3059 | .can_merge = 0, |
3060 | .map = generic_pipe_buf_map, | |
3061 | .unmap = generic_pipe_buf_unmap, | |
3062 | .confirm = generic_pipe_buf_confirm, | |
3063 | .release = tracing_pipe_buf_release, | |
3064 | .steal = generic_pipe_buf_steal, | |
3065 | .get = generic_pipe_buf_get, | |
3c56819b EGM |
3066 | }; |
3067 | ||
34cd4998 | 3068 | static size_t |
fa7c7f6e | 3069 | tracing_fill_pipe_page(size_t rem, struct trace_iterator *iter) |
34cd4998 SR |
3070 | { |
3071 | size_t count; | |
3072 | int ret; | |
3073 | ||
3074 | /* Seq buffer is page-sized, exactly what we need. */ | |
3075 | for (;;) { | |
3076 | count = iter->seq.len; | |
3077 | ret = print_trace_line(iter); | |
3078 | count = iter->seq.len - count; | |
3079 | if (rem < count) { | |
3080 | rem = 0; | |
3081 | iter->seq.len -= count; | |
3082 | break; | |
3083 | } | |
3084 | if (ret == TRACE_TYPE_PARTIAL_LINE) { | |
3085 | iter->seq.len -= count; | |
3086 | break; | |
3087 | } | |
3088 | ||
3089 | trace_consume(iter); | |
3090 | rem -= count; | |
3091 | if (!find_next_entry_inc(iter)) { | |
3092 | rem = 0; | |
3093 | iter->ent = NULL; | |
3094 | break; | |
3095 | } | |
3096 | } | |
3097 | ||
3098 | return rem; | |
3099 | } | |
3100 | ||
3c56819b EGM |
3101 | static ssize_t tracing_splice_read_pipe(struct file *filp, |
3102 | loff_t *ppos, | |
3103 | struct pipe_inode_info *pipe, | |
3104 | size_t len, | |
3105 | unsigned int flags) | |
3106 | { | |
3107 | struct page *pages[PIPE_BUFFERS]; | |
3108 | struct partial_page partial[PIPE_BUFFERS]; | |
3109 | struct trace_iterator *iter = filp->private_data; | |
3110 | struct splice_pipe_desc spd = { | |
34cd4998 SR |
3111 | .pages = pages, |
3112 | .partial = partial, | |
3113 | .nr_pages = 0, /* This gets updated below. */ | |
3114 | .flags = flags, | |
3115 | .ops = &tracing_pipe_buf_ops, | |
3116 | .spd_release = tracing_spd_release_pipe, | |
3c56819b | 3117 | }; |
d7350c3f | 3118 | static struct tracer *old_tracer; |
3c56819b | 3119 | ssize_t ret; |
34cd4998 | 3120 | size_t rem; |
3c56819b EGM |
3121 | unsigned int i; |
3122 | ||
d7350c3f | 3123 | /* copy the tracer to avoid using a global lock all around */ |
3c56819b | 3124 | mutex_lock(&trace_types_lock); |
d7350c3f FW |
3125 | if (unlikely(old_tracer != current_trace && current_trace)) { |
3126 | old_tracer = current_trace; | |
3127 | *iter->trace = *current_trace; | |
3128 | } | |
3129 | mutex_unlock(&trace_types_lock); | |
3130 | ||
3131 | mutex_lock(&iter->mutex); | |
3c56819b EGM |
3132 | |
3133 | if (iter->trace->splice_read) { | |
3134 | ret = iter->trace->splice_read(iter, filp, | |
3135 | ppos, pipe, len, flags); | |
3136 | if (ret) | |
34cd4998 | 3137 | goto out_err; |
3c56819b EGM |
3138 | } |
3139 | ||
3140 | ret = tracing_wait_pipe(filp); | |
3141 | if (ret <= 0) | |
34cd4998 | 3142 | goto out_err; |
3c56819b EGM |
3143 | |
3144 | if (!iter->ent && !find_next_entry_inc(iter)) { | |
3145 | ret = -EFAULT; | |
34cd4998 | 3146 | goto out_err; |
3c56819b EGM |
3147 | } |
3148 | ||
3149 | /* Fill as many pages as possible. */ | |
3150 | for (i = 0, rem = len; i < PIPE_BUFFERS && rem; i++) { | |
3151 | pages[i] = alloc_page(GFP_KERNEL); | |
34cd4998 SR |
3152 | if (!pages[i]) |
3153 | break; | |
3c56819b | 3154 | |
fa7c7f6e | 3155 | rem = tracing_fill_pipe_page(rem, iter); |
3c56819b EGM |
3156 | |
3157 | /* Copy the data into the page, so we can start over. */ | |
3158 | ret = trace_seq_to_buffer(&iter->seq, | |
3159 | page_address(pages[i]), | |
3160 | iter->seq.len); | |
3161 | if (ret < 0) { | |
3162 | __free_page(pages[i]); | |
3163 | break; | |
3164 | } | |
3165 | partial[i].offset = 0; | |
3166 | partial[i].len = iter->seq.len; | |
3167 | ||
f9520750 | 3168 | trace_seq_init(&iter->seq); |
3c56819b EGM |
3169 | } |
3170 | ||
d7350c3f | 3171 | mutex_unlock(&iter->mutex); |
3c56819b EGM |
3172 | |
3173 | spd.nr_pages = i; | |
3174 | ||
3175 | return splice_to_pipe(pipe, &spd); | |
3176 | ||
34cd4998 | 3177 | out_err: |
d7350c3f | 3178 | mutex_unlock(&iter->mutex); |
3c56819b EGM |
3179 | |
3180 | return ret; | |
3181 | } | |
3182 | ||
a98a3c3f SR |
3183 | static ssize_t |
3184 | tracing_entries_read(struct file *filp, char __user *ubuf, | |
3185 | size_t cnt, loff_t *ppos) | |
3186 | { | |
3187 | struct trace_array *tr = filp->private_data; | |
db526ca3 | 3188 | char buf[96]; |
a98a3c3f SR |
3189 | int r; |
3190 | ||
db526ca3 SR |
3191 | mutex_lock(&trace_types_lock); |
3192 | if (!ring_buffer_expanded) | |
3193 | r = sprintf(buf, "%lu (expanded: %lu)\n", | |
3194 | tr->entries >> 10, | |
3195 | trace_buf_size >> 10); | |
3196 | else | |
3197 | r = sprintf(buf, "%lu\n", tr->entries >> 10); | |
3198 | mutex_unlock(&trace_types_lock); | |
3199 | ||
a98a3c3f SR |
3200 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, r); |
3201 | } | |
3202 | ||
3203 | static ssize_t | |
3204 | tracing_entries_write(struct file *filp, const char __user *ubuf, | |
3205 | size_t cnt, loff_t *ppos) | |
3206 | { | |
3207 | unsigned long val; | |
3208 | char buf[64]; | |
bf5e6519 | 3209 | int ret, cpu; |
a98a3c3f | 3210 | |
cffae437 SR |
3211 | if (cnt >= sizeof(buf)) |
3212 | return -EINVAL; | |
a98a3c3f SR |
3213 | |
3214 | if (copy_from_user(&buf, ubuf, cnt)) | |
3215 | return -EFAULT; | |
3216 | ||
3217 | buf[cnt] = 0; | |
3218 | ||
c6caeeb1 SR |
3219 | ret = strict_strtoul(buf, 10, &val); |
3220 | if (ret < 0) | |
3221 | return ret; | |
a98a3c3f SR |
3222 | |
3223 | /* must have at least 1 entry */ | |
3224 | if (!val) | |
3225 | return -EINVAL; | |
3226 | ||
3227 | mutex_lock(&trace_types_lock); | |
3228 | ||
c76f0694 | 3229 | tracing_stop(); |
a98a3c3f | 3230 | |
bf5e6519 SR |
3231 | /* disable all cpu buffers */ |
3232 | for_each_tracing_cpu(cpu) { | |
3233 | if (global_trace.data[cpu]) | |
3234 | atomic_inc(&global_trace.data[cpu]->disabled); | |
3235 | if (max_tr.data[cpu]) | |
3236 | atomic_inc(&max_tr.data[cpu]->disabled); | |
3237 | } | |
3238 | ||
1696b2b0 SR |
3239 | /* value is in KB */ |
3240 | val <<= 10; | |
3241 | ||
3928a8a2 | 3242 | if (val != global_trace.entries) { |
73c5162a | 3243 | ret = tracing_resize_ring_buffer(val); |
3928a8a2 SR |
3244 | if (ret < 0) { |
3245 | cnt = ret; | |
3eefae99 SR |
3246 | goto out; |
3247 | } | |
a98a3c3f SR |
3248 | } |
3249 | ||
3250 | filp->f_pos += cnt; | |
3251 | ||
19384c03 SR |
3252 | /* If check pages failed, return ENOMEM */ |
3253 | if (tracing_disabled) | |
3254 | cnt = -ENOMEM; | |
a98a3c3f | 3255 | out: |
bf5e6519 SR |
3256 | for_each_tracing_cpu(cpu) { |
3257 | if (global_trace.data[cpu]) | |
3258 | atomic_dec(&global_trace.data[cpu]->disabled); | |
3259 | if (max_tr.data[cpu]) | |
3260 | atomic_dec(&max_tr.data[cpu]->disabled); | |
3261 | } | |
3262 | ||
c76f0694 | 3263 | tracing_start(); |
a98a3c3f SR |
3264 | max_tr.entries = global_trace.entries; |
3265 | mutex_unlock(&trace_types_lock); | |
3266 | ||
3267 | return cnt; | |
3268 | } | |
3269 | ||
5bf9a1ee PP |
3270 | static int mark_printk(const char *fmt, ...) |
3271 | { | |
3272 | int ret; | |
3273 | va_list args; | |
3274 | va_start(args, fmt); | |
40ce74f1 | 3275 | ret = trace_vprintk(0, fmt, args); |
5bf9a1ee PP |
3276 | va_end(args); |
3277 | return ret; | |
3278 | } | |
3279 | ||
3280 | static ssize_t | |
3281 | tracing_mark_write(struct file *filp, const char __user *ubuf, | |
3282 | size_t cnt, loff_t *fpos) | |
3283 | { | |
3284 | char *buf; | |
3285 | char *end; | |
5bf9a1ee | 3286 | |
c76f0694 | 3287 | if (tracing_disabled) |
5bf9a1ee PP |
3288 | return -EINVAL; |
3289 | ||
3290 | if (cnt > TRACE_BUF_SIZE) | |
3291 | cnt = TRACE_BUF_SIZE; | |
3292 | ||
3293 | buf = kmalloc(cnt + 1, GFP_KERNEL); | |
3294 | if (buf == NULL) | |
3295 | return -ENOMEM; | |
3296 | ||
3297 | if (copy_from_user(buf, ubuf, cnt)) { | |
3298 | kfree(buf); | |
3299 | return -EFAULT; | |
3300 | } | |
3301 | ||
3302 | /* Cut from the first nil or newline. */ | |
3303 | buf[cnt] = '\0'; | |
3304 | end = strchr(buf, '\n'); | |
3305 | if (end) | |
3306 | *end = '\0'; | |
3307 | ||
3308 | cnt = mark_printk("%s\n", buf); | |
3309 | kfree(buf); | |
3310 | *fpos += cnt; | |
3311 | ||
3312 | return cnt; | |
3313 | } | |
3314 | ||
5e2336a0 | 3315 | static const struct file_operations tracing_max_lat_fops = { |
4bf39a94 IM |
3316 | .open = tracing_open_generic, |
3317 | .read = tracing_max_lat_read, | |
3318 | .write = tracing_max_lat_write, | |
bc0c38d1 SR |
3319 | }; |
3320 | ||
5e2336a0 | 3321 | static const struct file_operations tracing_ctrl_fops = { |
4bf39a94 IM |
3322 | .open = tracing_open_generic, |
3323 | .read = tracing_ctrl_read, | |
3324 | .write = tracing_ctrl_write, | |
bc0c38d1 SR |
3325 | }; |
3326 | ||
5e2336a0 | 3327 | static const struct file_operations set_tracer_fops = { |
4bf39a94 IM |
3328 | .open = tracing_open_generic, |
3329 | .read = tracing_set_trace_read, | |
3330 | .write = tracing_set_trace_write, | |
bc0c38d1 SR |
3331 | }; |
3332 | ||
5e2336a0 | 3333 | static const struct file_operations tracing_pipe_fops = { |
4bf39a94 | 3334 | .open = tracing_open_pipe, |
2a2cc8f7 | 3335 | .poll = tracing_poll_pipe, |
4bf39a94 | 3336 | .read = tracing_read_pipe, |
3c56819b | 3337 | .splice_read = tracing_splice_read_pipe, |
4bf39a94 | 3338 | .release = tracing_release_pipe, |
b3806b43 SR |
3339 | }; |
3340 | ||
5e2336a0 | 3341 | static const struct file_operations tracing_entries_fops = { |
a98a3c3f SR |
3342 | .open = tracing_open_generic, |
3343 | .read = tracing_entries_read, | |
3344 | .write = tracing_entries_write, | |
3345 | }; | |
3346 | ||
5e2336a0 | 3347 | static const struct file_operations tracing_mark_fops = { |
43a15386 | 3348 | .open = tracing_open_generic, |
5bf9a1ee PP |
3349 | .write = tracing_mark_write, |
3350 | }; | |
3351 | ||
2cadf913 SR |
3352 | struct ftrace_buffer_info { |
3353 | struct trace_array *tr; | |
3354 | void *spare; | |
3355 | int cpu; | |
3356 | unsigned int read; | |
3357 | }; | |
3358 | ||
3359 | static int tracing_buffers_open(struct inode *inode, struct file *filp) | |
3360 | { | |
3361 | int cpu = (int)(long)inode->i_private; | |
3362 | struct ftrace_buffer_info *info; | |
3363 | ||
3364 | if (tracing_disabled) | |
3365 | return -ENODEV; | |
3366 | ||
3367 | info = kzalloc(sizeof(*info), GFP_KERNEL); | |
3368 | if (!info) | |
3369 | return -ENOMEM; | |
3370 | ||
3371 | info->tr = &global_trace; | |
3372 | info->cpu = cpu; | |
ddd538f3 | 3373 | info->spare = NULL; |
2cadf913 SR |
3374 | /* Force reading ring buffer for first read */ |
3375 | info->read = (unsigned int)-1; | |
2cadf913 SR |
3376 | |
3377 | filp->private_data = info; | |
3378 | ||
d1e7e02f | 3379 | return nonseekable_open(inode, filp); |
2cadf913 SR |
3380 | } |
3381 | ||
3382 | static ssize_t | |
3383 | tracing_buffers_read(struct file *filp, char __user *ubuf, | |
3384 | size_t count, loff_t *ppos) | |
3385 | { | |
3386 | struct ftrace_buffer_info *info = filp->private_data; | |
3387 | unsigned int pos; | |
3388 | ssize_t ret; | |
3389 | size_t size; | |
3390 | ||
2dc5d12b SR |
3391 | if (!count) |
3392 | return 0; | |
3393 | ||
ddd538f3 LJ |
3394 | if (!info->spare) |
3395 | info->spare = ring_buffer_alloc_read_page(info->tr->buffer); | |
3396 | if (!info->spare) | |
3397 | return -ENOMEM; | |
3398 | ||
2cadf913 SR |
3399 | /* Do we have previous read data to read? */ |
3400 | if (info->read < PAGE_SIZE) | |
3401 | goto read; | |
3402 | ||
3403 | info->read = 0; | |
3404 | ||
3405 | ret = ring_buffer_read_page(info->tr->buffer, | |
3406 | &info->spare, | |
3407 | count, | |
3408 | info->cpu, 0); | |
3409 | if (ret < 0) | |
3410 | return 0; | |
3411 | ||
3412 | pos = ring_buffer_page_len(info->spare); | |
3413 | ||
3414 | if (pos < PAGE_SIZE) | |
3415 | memset(info->spare + pos, 0, PAGE_SIZE - pos); | |
3416 | ||
3417 | read: | |
3418 | size = PAGE_SIZE - info->read; | |
3419 | if (size > count) | |
3420 | size = count; | |
3421 | ||
3422 | ret = copy_to_user(ubuf, info->spare + info->read, size); | |
2dc5d12b | 3423 | if (ret == size) |
2cadf913 | 3424 | return -EFAULT; |
2dc5d12b SR |
3425 | size -= ret; |
3426 | ||
2cadf913 SR |
3427 | *ppos += size; |
3428 | info->read += size; | |
3429 | ||
3430 | return size; | |
3431 | } | |
3432 | ||
3433 | static int tracing_buffers_release(struct inode *inode, struct file *file) | |
3434 | { | |
3435 | struct ftrace_buffer_info *info = file->private_data; | |
3436 | ||
ddd538f3 LJ |
3437 | if (info->spare) |
3438 | ring_buffer_free_read_page(info->tr->buffer, info->spare); | |
2cadf913 SR |
3439 | kfree(info); |
3440 | ||
3441 | return 0; | |
3442 | } | |
3443 | ||
3444 | struct buffer_ref { | |
3445 | struct ring_buffer *buffer; | |
3446 | void *page; | |
3447 | int ref; | |
3448 | }; | |
3449 | ||
3450 | static void buffer_pipe_buf_release(struct pipe_inode_info *pipe, | |
3451 | struct pipe_buffer *buf) | |
3452 | { | |
3453 | struct buffer_ref *ref = (struct buffer_ref *)buf->private; | |
3454 | ||
3455 | if (--ref->ref) | |
3456 | return; | |
3457 | ||
3458 | ring_buffer_free_read_page(ref->buffer, ref->page); | |
3459 | kfree(ref); | |
3460 | buf->private = 0; | |
3461 | } | |
3462 | ||
3463 | static int buffer_pipe_buf_steal(struct pipe_inode_info *pipe, | |
3464 | struct pipe_buffer *buf) | |
3465 | { | |
3466 | return 1; | |
3467 | } | |
3468 | ||
3469 | static void buffer_pipe_buf_get(struct pipe_inode_info *pipe, | |
3470 | struct pipe_buffer *buf) | |
3471 | { | |
3472 | struct buffer_ref *ref = (struct buffer_ref *)buf->private; | |
3473 | ||
3474 | ref->ref++; | |
3475 | } | |
3476 | ||
3477 | /* Pipe buffer operations for a buffer. */ | |
3478 | static struct pipe_buf_operations buffer_pipe_buf_ops = { | |
3479 | .can_merge = 0, | |
3480 | .map = generic_pipe_buf_map, | |
3481 | .unmap = generic_pipe_buf_unmap, | |
3482 | .confirm = generic_pipe_buf_confirm, | |
3483 | .release = buffer_pipe_buf_release, | |
3484 | .steal = buffer_pipe_buf_steal, | |
3485 | .get = buffer_pipe_buf_get, | |
3486 | }; | |
3487 | ||
3488 | /* | |
3489 | * Callback from splice_to_pipe(), if we need to release some pages | |
3490 | * at the end of the spd in case we error'ed out in filling the pipe. | |
3491 | */ | |
3492 | static void buffer_spd_release(struct splice_pipe_desc *spd, unsigned int i) | |
3493 | { | |
3494 | struct buffer_ref *ref = | |
3495 | (struct buffer_ref *)spd->partial[i].private; | |
3496 | ||
3497 | if (--ref->ref) | |
3498 | return; | |
3499 | ||
3500 | ring_buffer_free_read_page(ref->buffer, ref->page); | |
3501 | kfree(ref); | |
3502 | spd->partial[i].private = 0; | |
3503 | } | |
3504 | ||
3505 | static ssize_t | |
3506 | tracing_buffers_splice_read(struct file *file, loff_t *ppos, | |
3507 | struct pipe_inode_info *pipe, size_t len, | |
3508 | unsigned int flags) | |
3509 | { | |
3510 | struct ftrace_buffer_info *info = file->private_data; | |
3511 | struct partial_page partial[PIPE_BUFFERS]; | |
3512 | struct page *pages[PIPE_BUFFERS]; | |
3513 | struct splice_pipe_desc spd = { | |
3514 | .pages = pages, | |
3515 | .partial = partial, | |
3516 | .flags = flags, | |
3517 | .ops = &buffer_pipe_buf_ops, | |
3518 | .spd_release = buffer_spd_release, | |
3519 | }; | |
3520 | struct buffer_ref *ref; | |
93459c6c | 3521 | int entries, size, i; |
2cadf913 SR |
3522 | size_t ret; |
3523 | ||
93cfb3c9 LJ |
3524 | if (*ppos & (PAGE_SIZE - 1)) { |
3525 | WARN_ONCE(1, "Ftrace: previous read must page-align\n"); | |
3526 | return -EINVAL; | |
3527 | } | |
2cadf913 | 3528 | |
93cfb3c9 LJ |
3529 | if (len & (PAGE_SIZE - 1)) { |
3530 | WARN_ONCE(1, "Ftrace: splice_read should page-align\n"); | |
3531 | if (len < PAGE_SIZE) | |
3532 | return -EINVAL; | |
3533 | len &= PAGE_MASK; | |
3534 | } | |
2cadf913 | 3535 | |
93459c6c SR |
3536 | entries = ring_buffer_entries_cpu(info->tr->buffer, info->cpu); |
3537 | ||
3538 | for (i = 0; i < PIPE_BUFFERS && len && entries; i++, len -= PAGE_SIZE) { | |
2cadf913 SR |
3539 | struct page *page; |
3540 | int r; | |
3541 | ||
3542 | ref = kzalloc(sizeof(*ref), GFP_KERNEL); | |
3543 | if (!ref) | |
3544 | break; | |
3545 | ||
5beae6ef | 3546 | ref->ref = 1; |
2cadf913 SR |
3547 | ref->buffer = info->tr->buffer; |
3548 | ref->page = ring_buffer_alloc_read_page(ref->buffer); | |
3549 | if (!ref->page) { | |
3550 | kfree(ref); | |
3551 | break; | |
3552 | } | |
3553 | ||
3554 | r = ring_buffer_read_page(ref->buffer, &ref->page, | |
f2957f1f | 3555 | len, info->cpu, 1); |
2cadf913 SR |
3556 | if (r < 0) { |
3557 | ring_buffer_free_read_page(ref->buffer, | |
3558 | ref->page); | |
3559 | kfree(ref); | |
3560 | break; | |
3561 | } | |
3562 | ||
3563 | /* | |
3564 | * zero out any left over data, this is going to | |
3565 | * user land. | |
3566 | */ | |
3567 | size = ring_buffer_page_len(ref->page); | |
3568 | if (size < PAGE_SIZE) | |
3569 | memset(ref->page + size, 0, PAGE_SIZE - size); | |
3570 | ||
3571 | page = virt_to_page(ref->page); | |
3572 | ||
3573 | spd.pages[i] = page; | |
3574 | spd.partial[i].len = PAGE_SIZE; | |
3575 | spd.partial[i].offset = 0; | |
3576 | spd.partial[i].private = (unsigned long)ref; | |
3577 | spd.nr_pages++; | |
93cfb3c9 | 3578 | *ppos += PAGE_SIZE; |
93459c6c SR |
3579 | |
3580 | entries = ring_buffer_entries_cpu(info->tr->buffer, info->cpu); | |
2cadf913 SR |
3581 | } |
3582 | ||
3583 | spd.nr_pages = i; | |
3584 | ||
3585 | /* did we read anything? */ | |
3586 | if (!spd.nr_pages) { | |
3587 | if (flags & SPLICE_F_NONBLOCK) | |
3588 | ret = -EAGAIN; | |
3589 | else | |
3590 | ret = 0; | |
3591 | /* TODO: block */ | |
3592 | return ret; | |
3593 | } | |
3594 | ||
3595 | ret = splice_to_pipe(pipe, &spd); | |
3596 | ||
3597 | return ret; | |
3598 | } | |
3599 | ||
3600 | static const struct file_operations tracing_buffers_fops = { | |
3601 | .open = tracing_buffers_open, | |
3602 | .read = tracing_buffers_read, | |
3603 | .release = tracing_buffers_release, | |
3604 | .splice_read = tracing_buffers_splice_read, | |
3605 | .llseek = no_llseek, | |
3606 | }; | |
3607 | ||
c8d77183 SR |
3608 | static ssize_t |
3609 | tracing_stats_read(struct file *filp, char __user *ubuf, | |
3610 | size_t count, loff_t *ppos) | |
3611 | { | |
3612 | unsigned long cpu = (unsigned long)filp->private_data; | |
3613 | struct trace_array *tr = &global_trace; | |
3614 | struct trace_seq *s; | |
3615 | unsigned long cnt; | |
3616 | ||
3617 | s = kmalloc(sizeof(*s), GFP_ATOMIC); | |
3618 | if (!s) | |
3619 | return ENOMEM; | |
3620 | ||
3621 | trace_seq_init(s); | |
3622 | ||
3623 | cnt = ring_buffer_entries_cpu(tr->buffer, cpu); | |
3624 | trace_seq_printf(s, "entries: %ld\n", cnt); | |
3625 | ||
3626 | cnt = ring_buffer_overrun_cpu(tr->buffer, cpu); | |
3627 | trace_seq_printf(s, "overrun: %ld\n", cnt); | |
3628 | ||
3629 | cnt = ring_buffer_commit_overrun_cpu(tr->buffer, cpu); | |
3630 | trace_seq_printf(s, "commit overrun: %ld\n", cnt); | |
3631 | ||
3632 | cnt = ring_buffer_nmi_dropped_cpu(tr->buffer, cpu); | |
3633 | trace_seq_printf(s, "nmi dropped: %ld\n", cnt); | |
3634 | ||
3635 | count = simple_read_from_buffer(ubuf, count, ppos, s->buffer, s->len); | |
3636 | ||
3637 | kfree(s); | |
3638 | ||
3639 | return count; | |
3640 | } | |
3641 | ||
3642 | static const struct file_operations tracing_stats_fops = { | |
3643 | .open = tracing_open_generic, | |
3644 | .read = tracing_stats_read, | |
3645 | }; | |
3646 | ||
bc0c38d1 SR |
3647 | #ifdef CONFIG_DYNAMIC_FTRACE |
3648 | ||
b807c3d0 SR |
3649 | int __weak ftrace_arch_read_dyn_info(char *buf, int size) |
3650 | { | |
3651 | return 0; | |
3652 | } | |
3653 | ||
bc0c38d1 | 3654 | static ssize_t |
b807c3d0 | 3655 | tracing_read_dyn_info(struct file *filp, char __user *ubuf, |
bc0c38d1 SR |
3656 | size_t cnt, loff_t *ppos) |
3657 | { | |
a26a2a27 SR |
3658 | static char ftrace_dyn_info_buffer[1024]; |
3659 | static DEFINE_MUTEX(dyn_info_mutex); | |
bc0c38d1 | 3660 | unsigned long *p = filp->private_data; |
b807c3d0 | 3661 | char *buf = ftrace_dyn_info_buffer; |
a26a2a27 | 3662 | int size = ARRAY_SIZE(ftrace_dyn_info_buffer); |
bc0c38d1 SR |
3663 | int r; |
3664 | ||
b807c3d0 SR |
3665 | mutex_lock(&dyn_info_mutex); |
3666 | r = sprintf(buf, "%ld ", *p); | |
4bf39a94 | 3667 | |
a26a2a27 | 3668 | r += ftrace_arch_read_dyn_info(buf+r, (size-1)-r); |
b807c3d0 SR |
3669 | buf[r++] = '\n'; |
3670 | ||
3671 | r = simple_read_from_buffer(ubuf, cnt, ppos, buf, r); | |
3672 | ||
3673 | mutex_unlock(&dyn_info_mutex); | |
3674 | ||
3675 | return r; | |
bc0c38d1 SR |
3676 | } |
3677 | ||
5e2336a0 | 3678 | static const struct file_operations tracing_dyn_info_fops = { |
4bf39a94 | 3679 | .open = tracing_open_generic, |
b807c3d0 | 3680 | .read = tracing_read_dyn_info, |
bc0c38d1 SR |
3681 | }; |
3682 | #endif | |
3683 | ||
3684 | static struct dentry *d_tracer; | |
3685 | ||
3686 | struct dentry *tracing_init_dentry(void) | |
3687 | { | |
3688 | static int once; | |
3689 | ||
3690 | if (d_tracer) | |
3691 | return d_tracer; | |
3692 | ||
3e1f60b8 FW |
3693 | if (!debugfs_initialized()) |
3694 | return NULL; | |
3695 | ||
bc0c38d1 SR |
3696 | d_tracer = debugfs_create_dir("tracing", NULL); |
3697 | ||
3698 | if (!d_tracer && !once) { | |
3699 | once = 1; | |
3700 | pr_warning("Could not create debugfs directory 'tracing'\n"); | |
3701 | return NULL; | |
3702 | } | |
3703 | ||
3704 | return d_tracer; | |
3705 | } | |
3706 | ||
b04cc6b1 FW |
3707 | static struct dentry *d_percpu; |
3708 | ||
3709 | struct dentry *tracing_dentry_percpu(void) | |
3710 | { | |
3711 | static int once; | |
3712 | struct dentry *d_tracer; | |
3713 | ||
3714 | if (d_percpu) | |
3715 | return d_percpu; | |
3716 | ||
3717 | d_tracer = tracing_init_dentry(); | |
3718 | ||
3719 | if (!d_tracer) | |
3720 | return NULL; | |
3721 | ||
3722 | d_percpu = debugfs_create_dir("per_cpu", d_tracer); | |
3723 | ||
3724 | if (!d_percpu && !once) { | |
3725 | once = 1; | |
3726 | pr_warning("Could not create debugfs directory 'per_cpu'\n"); | |
3727 | return NULL; | |
3728 | } | |
3729 | ||
3730 | return d_percpu; | |
3731 | } | |
3732 | ||
3733 | static void tracing_init_debugfs_percpu(long cpu) | |
3734 | { | |
3735 | struct dentry *d_percpu = tracing_dentry_percpu(); | |
5452af66 | 3736 | struct dentry *d_cpu; |
8656e7a2 FW |
3737 | /* strlen(cpu) + MAX(log10(cpu)) + '\0' */ |
3738 | char cpu_dir[7]; | |
b04cc6b1 FW |
3739 | |
3740 | if (cpu > 999 || cpu < 0) | |
3741 | return; | |
3742 | ||
8656e7a2 FW |
3743 | sprintf(cpu_dir, "cpu%ld", cpu); |
3744 | d_cpu = debugfs_create_dir(cpu_dir, d_percpu); | |
3745 | if (!d_cpu) { | |
3746 | pr_warning("Could not create debugfs '%s' entry\n", cpu_dir); | |
3747 | return; | |
3748 | } | |
b04cc6b1 | 3749 | |
8656e7a2 | 3750 | /* per cpu trace_pipe */ |
5452af66 FW |
3751 | trace_create_file("trace_pipe", 0444, d_cpu, |
3752 | (void *) cpu, &tracing_pipe_fops); | |
b04cc6b1 FW |
3753 | |
3754 | /* per cpu trace */ | |
5452af66 FW |
3755 | trace_create_file("trace", 0644, d_cpu, |
3756 | (void *) cpu, &tracing_fops); | |
7f96f93f | 3757 | |
5452af66 FW |
3758 | trace_create_file("trace_pipe_raw", 0444, d_cpu, |
3759 | (void *) cpu, &tracing_buffers_fops); | |
c8d77183 SR |
3760 | |
3761 | trace_create_file("stats", 0444, d_cpu, | |
3762 | (void *) cpu, &tracing_stats_fops); | |
b04cc6b1 FW |
3763 | } |
3764 | ||
60a11774 SR |
3765 | #ifdef CONFIG_FTRACE_SELFTEST |
3766 | /* Let selftest have access to static functions in this file */ | |
3767 | #include "trace_selftest.c" | |
3768 | #endif | |
3769 | ||
577b785f SR |
3770 | struct trace_option_dentry { |
3771 | struct tracer_opt *opt; | |
3772 | struct tracer_flags *flags; | |
3773 | struct dentry *entry; | |
3774 | }; | |
3775 | ||
3776 | static ssize_t | |
3777 | trace_options_read(struct file *filp, char __user *ubuf, size_t cnt, | |
3778 | loff_t *ppos) | |
3779 | { | |
3780 | struct trace_option_dentry *topt = filp->private_data; | |
3781 | char *buf; | |
3782 | ||
3783 | if (topt->flags->val & topt->opt->bit) | |
3784 | buf = "1\n"; | |
3785 | else | |
3786 | buf = "0\n"; | |
3787 | ||
3788 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, 2); | |
3789 | } | |
3790 | ||
3791 | static ssize_t | |
3792 | trace_options_write(struct file *filp, const char __user *ubuf, size_t cnt, | |
3793 | loff_t *ppos) | |
3794 | { | |
3795 | struct trace_option_dentry *topt = filp->private_data; | |
3796 | unsigned long val; | |
3797 | char buf[64]; | |
3798 | int ret; | |
3799 | ||
3800 | if (cnt >= sizeof(buf)) | |
3801 | return -EINVAL; | |
3802 | ||
3803 | if (copy_from_user(&buf, ubuf, cnt)) | |
3804 | return -EFAULT; | |
3805 | ||
3806 | buf[cnt] = 0; | |
3807 | ||
3808 | ret = strict_strtoul(buf, 10, &val); | |
3809 | if (ret < 0) | |
3810 | return ret; | |
3811 | ||
3812 | ret = 0; | |
3813 | switch (val) { | |
3814 | case 0: | |
3815 | /* do nothing if already cleared */ | |
3816 | if (!(topt->flags->val & topt->opt->bit)) | |
3817 | break; | |
3818 | ||
3819 | mutex_lock(&trace_types_lock); | |
3820 | if (current_trace->set_flag) | |
3821 | ret = current_trace->set_flag(topt->flags->val, | |
3822 | topt->opt->bit, 0); | |
3823 | mutex_unlock(&trace_types_lock); | |
3824 | if (ret) | |
3825 | return ret; | |
3826 | topt->flags->val &= ~topt->opt->bit; | |
3827 | break; | |
3828 | case 1: | |
3829 | /* do nothing if already set */ | |
3830 | if (topt->flags->val & topt->opt->bit) | |
3831 | break; | |
3832 | ||
3833 | mutex_lock(&trace_types_lock); | |
3834 | if (current_trace->set_flag) | |
3835 | ret = current_trace->set_flag(topt->flags->val, | |
3836 | topt->opt->bit, 1); | |
3837 | mutex_unlock(&trace_types_lock); | |
3838 | if (ret) | |
3839 | return ret; | |
3840 | topt->flags->val |= topt->opt->bit; | |
3841 | break; | |
3842 | ||
3843 | default: | |
3844 | return -EINVAL; | |
3845 | } | |
3846 | ||
3847 | *ppos += cnt; | |
3848 | ||
3849 | return cnt; | |
3850 | } | |
3851 | ||
3852 | ||
3853 | static const struct file_operations trace_options_fops = { | |
3854 | .open = tracing_open_generic, | |
3855 | .read = trace_options_read, | |
3856 | .write = trace_options_write, | |
3857 | }; | |
3858 | ||
a8259075 SR |
3859 | static ssize_t |
3860 | trace_options_core_read(struct file *filp, char __user *ubuf, size_t cnt, | |
3861 | loff_t *ppos) | |
3862 | { | |
3863 | long index = (long)filp->private_data; | |
3864 | char *buf; | |
3865 | ||
3866 | if (trace_flags & (1 << index)) | |
3867 | buf = "1\n"; | |
3868 | else | |
3869 | buf = "0\n"; | |
3870 | ||
3871 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, 2); | |
3872 | } | |
3873 | ||
3874 | static ssize_t | |
3875 | trace_options_core_write(struct file *filp, const char __user *ubuf, size_t cnt, | |
3876 | loff_t *ppos) | |
3877 | { | |
3878 | long index = (long)filp->private_data; | |
3879 | char buf[64]; | |
3880 | unsigned long val; | |
3881 | int ret; | |
3882 | ||
3883 | if (cnt >= sizeof(buf)) | |
3884 | return -EINVAL; | |
3885 | ||
3886 | if (copy_from_user(&buf, ubuf, cnt)) | |
3887 | return -EFAULT; | |
3888 | ||
3889 | buf[cnt] = 0; | |
3890 | ||
3891 | ret = strict_strtoul(buf, 10, &val); | |
3892 | if (ret < 0) | |
3893 | return ret; | |
3894 | ||
3895 | switch (val) { | |
3896 | case 0: | |
3897 | trace_flags &= ~(1 << index); | |
3898 | break; | |
3899 | case 1: | |
3900 | trace_flags |= 1 << index; | |
3901 | break; | |
3902 | ||
3903 | default: | |
3904 | return -EINVAL; | |
3905 | } | |
3906 | ||
3907 | *ppos += cnt; | |
3908 | ||
3909 | return cnt; | |
3910 | } | |
3911 | ||
a8259075 SR |
3912 | static const struct file_operations trace_options_core_fops = { |
3913 | .open = tracing_open_generic, | |
3914 | .read = trace_options_core_read, | |
3915 | .write = trace_options_core_write, | |
3916 | }; | |
3917 | ||
5452af66 FW |
3918 | struct dentry *trace_create_file(const char *name, |
3919 | mode_t mode, | |
3920 | struct dentry *parent, | |
3921 | void *data, | |
3922 | const struct file_operations *fops) | |
3923 | { | |
3924 | struct dentry *ret; | |
3925 | ||
3926 | ret = debugfs_create_file(name, mode, parent, data, fops); | |
3927 | if (!ret) | |
3928 | pr_warning("Could not create debugfs '%s' entry\n", name); | |
3929 | ||
3930 | return ret; | |
3931 | } | |
3932 | ||
3933 | ||
a8259075 SR |
3934 | static struct dentry *trace_options_init_dentry(void) |
3935 | { | |
3936 | struct dentry *d_tracer; | |
3937 | static struct dentry *t_options; | |
3938 | ||
3939 | if (t_options) | |
3940 | return t_options; | |
3941 | ||
3942 | d_tracer = tracing_init_dentry(); | |
3943 | if (!d_tracer) | |
3944 | return NULL; | |
3945 | ||
3946 | t_options = debugfs_create_dir("options", d_tracer); | |
3947 | if (!t_options) { | |
3948 | pr_warning("Could not create debugfs directory 'options'\n"); | |
3949 | return NULL; | |
3950 | } | |
3951 | ||
3952 | return t_options; | |
3953 | } | |
3954 | ||
577b785f SR |
3955 | static void |
3956 | create_trace_option_file(struct trace_option_dentry *topt, | |
3957 | struct tracer_flags *flags, | |
3958 | struct tracer_opt *opt) | |
3959 | { | |
3960 | struct dentry *t_options; | |
577b785f SR |
3961 | |
3962 | t_options = trace_options_init_dentry(); | |
3963 | if (!t_options) | |
3964 | return; | |
3965 | ||
3966 | topt->flags = flags; | |
3967 | topt->opt = opt; | |
3968 | ||
5452af66 | 3969 | topt->entry = trace_create_file(opt->name, 0644, t_options, topt, |
577b785f SR |
3970 | &trace_options_fops); |
3971 | ||
577b785f SR |
3972 | } |
3973 | ||
3974 | static struct trace_option_dentry * | |
3975 | create_trace_option_files(struct tracer *tracer) | |
3976 | { | |
3977 | struct trace_option_dentry *topts; | |
3978 | struct tracer_flags *flags; | |
3979 | struct tracer_opt *opts; | |
3980 | int cnt; | |
3981 | ||
3982 | if (!tracer) | |
3983 | return NULL; | |
3984 | ||
3985 | flags = tracer->flags; | |
3986 | ||
3987 | if (!flags || !flags->opts) | |
3988 | return NULL; | |
3989 | ||
3990 | opts = flags->opts; | |
3991 | ||
3992 | for (cnt = 0; opts[cnt].name; cnt++) | |
3993 | ; | |
3994 | ||
0cfe8245 | 3995 | topts = kcalloc(cnt + 1, sizeof(*topts), GFP_KERNEL); |
577b785f SR |
3996 | if (!topts) |
3997 | return NULL; | |
3998 | ||
3999 | for (cnt = 0; opts[cnt].name; cnt++) | |
4000 | create_trace_option_file(&topts[cnt], flags, | |
4001 | &opts[cnt]); | |
4002 | ||
4003 | return topts; | |
4004 | } | |
4005 | ||
4006 | static void | |
4007 | destroy_trace_option_files(struct trace_option_dentry *topts) | |
4008 | { | |
4009 | int cnt; | |
4010 | ||
4011 | if (!topts) | |
4012 | return; | |
4013 | ||
4014 | for (cnt = 0; topts[cnt].opt; cnt++) { | |
4015 | if (topts[cnt].entry) | |
4016 | debugfs_remove(topts[cnt].entry); | |
4017 | } | |
4018 | ||
4019 | kfree(topts); | |
4020 | } | |
4021 | ||
a8259075 SR |
4022 | static struct dentry * |
4023 | create_trace_option_core_file(const char *option, long index) | |
4024 | { | |
4025 | struct dentry *t_options; | |
a8259075 SR |
4026 | |
4027 | t_options = trace_options_init_dentry(); | |
4028 | if (!t_options) | |
4029 | return NULL; | |
4030 | ||
5452af66 | 4031 | return trace_create_file(option, 0644, t_options, (void *)index, |
a8259075 | 4032 | &trace_options_core_fops); |
a8259075 SR |
4033 | } |
4034 | ||
4035 | static __init void create_trace_options_dir(void) | |
4036 | { | |
4037 | struct dentry *t_options; | |
a8259075 SR |
4038 | int i; |
4039 | ||
4040 | t_options = trace_options_init_dentry(); | |
4041 | if (!t_options) | |
4042 | return; | |
4043 | ||
5452af66 FW |
4044 | for (i = 0; trace_options[i]; i++) |
4045 | create_trace_option_core_file(trace_options[i], i); | |
a8259075 SR |
4046 | } |
4047 | ||
b5ad384e | 4048 | static __init int tracer_init_debugfs(void) |
bc0c38d1 SR |
4049 | { |
4050 | struct dentry *d_tracer; | |
b04cc6b1 | 4051 | int cpu; |
bc0c38d1 SR |
4052 | |
4053 | d_tracer = tracing_init_dentry(); | |
4054 | ||
5452af66 FW |
4055 | trace_create_file("tracing_enabled", 0644, d_tracer, |
4056 | &global_trace, &tracing_ctrl_fops); | |
bc0c38d1 | 4057 | |
5452af66 FW |
4058 | trace_create_file("trace_options", 0644, d_tracer, |
4059 | NULL, &tracing_iter_fops); | |
bc0c38d1 | 4060 | |
5452af66 FW |
4061 | trace_create_file("tracing_cpumask", 0644, d_tracer, |
4062 | NULL, &tracing_cpumask_fops); | |
4063 | ||
4064 | trace_create_file("trace", 0644, d_tracer, | |
4065 | (void *) TRACE_PIPE_ALL_CPU, &tracing_fops); | |
4066 | ||
4067 | trace_create_file("available_tracers", 0444, d_tracer, | |
4068 | &global_trace, &show_traces_fops); | |
4069 | ||
339ae5d3 | 4070 | trace_create_file("current_tracer", 0644, d_tracer, |
5452af66 FW |
4071 | &global_trace, &set_tracer_fops); |
4072 | ||
4073 | trace_create_file("tracing_max_latency", 0644, d_tracer, | |
4074 | &tracing_max_latency, &tracing_max_lat_fops); | |
4075 | ||
4076 | trace_create_file("tracing_thresh", 0644, d_tracer, | |
4077 | &tracing_thresh, &tracing_max_lat_fops); | |
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); | |
4093 | ||
bc0c38d1 | 4094 | #ifdef CONFIG_DYNAMIC_FTRACE |
5452af66 FW |
4095 | trace_create_file("dyn_ftrace_total_info", 0444, d_tracer, |
4096 | &ftrace_update_tot_cnt, &tracing_dyn_info_fops); | |
bc0c38d1 | 4097 | #endif |
d618b3e6 IM |
4098 | #ifdef CONFIG_SYSPROF_TRACER |
4099 | init_tracer_sysprof_debugfs(d_tracer); | |
4100 | #endif | |
b04cc6b1 | 4101 | |
5452af66 FW |
4102 | create_trace_options_dir(); |
4103 | ||
b04cc6b1 FW |
4104 | for_each_tracing_cpu(cpu) |
4105 | tracing_init_debugfs_percpu(cpu); | |
4106 | ||
b5ad384e | 4107 | return 0; |
bc0c38d1 SR |
4108 | } |
4109 | ||
3f5a54e3 SR |
4110 | static int trace_panic_handler(struct notifier_block *this, |
4111 | unsigned long event, void *unused) | |
4112 | { | |
944ac425 SR |
4113 | if (ftrace_dump_on_oops) |
4114 | ftrace_dump(); | |
3f5a54e3 SR |
4115 | return NOTIFY_OK; |
4116 | } | |
4117 | ||
4118 | static struct notifier_block trace_panic_notifier = { | |
4119 | .notifier_call = trace_panic_handler, | |
4120 | .next = NULL, | |
4121 | .priority = 150 /* priority: INT_MAX >= x >= 0 */ | |
4122 | }; | |
4123 | ||
4124 | static int trace_die_handler(struct notifier_block *self, | |
4125 | unsigned long val, | |
4126 | void *data) | |
4127 | { | |
4128 | switch (val) { | |
4129 | case DIE_OOPS: | |
944ac425 SR |
4130 | if (ftrace_dump_on_oops) |
4131 | ftrace_dump(); | |
3f5a54e3 SR |
4132 | break; |
4133 | default: | |
4134 | break; | |
4135 | } | |
4136 | return NOTIFY_OK; | |
4137 | } | |
4138 | ||
4139 | static struct notifier_block trace_die_notifier = { | |
4140 | .notifier_call = trace_die_handler, | |
4141 | .priority = 200 | |
4142 | }; | |
4143 | ||
4144 | /* | |
4145 | * printk is set to max of 1024, we really don't need it that big. | |
4146 | * Nothing should be printing 1000 characters anyway. | |
4147 | */ | |
4148 | #define TRACE_MAX_PRINT 1000 | |
4149 | ||
4150 | /* | |
4151 | * Define here KERN_TRACE so that we have one place to modify | |
4152 | * it if we decide to change what log level the ftrace dump | |
4153 | * should be at. | |
4154 | */ | |
428aee14 | 4155 | #define KERN_TRACE KERN_EMERG |
3f5a54e3 SR |
4156 | |
4157 | static void | |
4158 | trace_printk_seq(struct trace_seq *s) | |
4159 | { | |
4160 | /* Probably should print a warning here. */ | |
4161 | if (s->len >= 1000) | |
4162 | s->len = 1000; | |
4163 | ||
4164 | /* should be zero ended, but we are paranoid. */ | |
4165 | s->buffer[s->len] = 0; | |
4166 | ||
4167 | printk(KERN_TRACE "%s", s->buffer); | |
4168 | ||
f9520750 | 4169 | trace_seq_init(s); |
3f5a54e3 SR |
4170 | } |
4171 | ||
cf586b61 | 4172 | static void __ftrace_dump(bool disable_tracing) |
3f5a54e3 | 4173 | { |
cd891ae0 SR |
4174 | static raw_spinlock_t ftrace_dump_lock = |
4175 | (raw_spinlock_t)__RAW_SPIN_LOCK_UNLOCKED; | |
3f5a54e3 SR |
4176 | /* use static because iter can be a bit big for the stack */ |
4177 | static struct trace_iterator iter; | |
cf586b61 | 4178 | unsigned int old_userobj; |
3f5a54e3 | 4179 | static int dump_ran; |
d769041f SR |
4180 | unsigned long flags; |
4181 | int cnt = 0, cpu; | |
3f5a54e3 SR |
4182 | |
4183 | /* only one dump */ | |
cd891ae0 SR |
4184 | local_irq_save(flags); |
4185 | __raw_spin_lock(&ftrace_dump_lock); | |
3f5a54e3 SR |
4186 | if (dump_ran) |
4187 | goto out; | |
4188 | ||
4189 | dump_ran = 1; | |
4190 | ||
0ee6b6cf | 4191 | tracing_off(); |
cf586b61 FW |
4192 | |
4193 | if (disable_tracing) | |
4194 | ftrace_kill(); | |
3f5a54e3 | 4195 | |
d769041f SR |
4196 | for_each_tracing_cpu(cpu) { |
4197 | atomic_inc(&global_trace.data[cpu]->disabled); | |
4198 | } | |
4199 | ||
cf586b61 FW |
4200 | old_userobj = trace_flags & TRACE_ITER_SYM_USEROBJ; |
4201 | ||
b54d3de9 TE |
4202 | /* don't look at user memory in panic mode */ |
4203 | trace_flags &= ~TRACE_ITER_SYM_USEROBJ; | |
4204 | ||
3f5a54e3 SR |
4205 | printk(KERN_TRACE "Dumping ftrace buffer:\n"); |
4206 | ||
e543ad76 | 4207 | /* Simulate the iterator */ |
3f5a54e3 SR |
4208 | iter.tr = &global_trace; |
4209 | iter.trace = current_trace; | |
e543ad76 | 4210 | iter.cpu_file = TRACE_PIPE_ALL_CPU; |
3f5a54e3 SR |
4211 | |
4212 | /* | |
4213 | * We need to stop all tracing on all CPUS to read the | |
4214 | * the next buffer. This is a bit expensive, but is | |
4215 | * not done often. We fill all what we can read, | |
4216 | * and then release the locks again. | |
4217 | */ | |
4218 | ||
3f5a54e3 SR |
4219 | while (!trace_empty(&iter)) { |
4220 | ||
4221 | if (!cnt) | |
4222 | printk(KERN_TRACE "---------------------------------\n"); | |
4223 | ||
4224 | cnt++; | |
4225 | ||
4226 | /* reset all but tr, trace, and overruns */ | |
4227 | memset(&iter.seq, 0, | |
4228 | sizeof(struct trace_iterator) - | |
4229 | offsetof(struct trace_iterator, seq)); | |
4230 | iter.iter_flags |= TRACE_FILE_LAT_FMT; | |
4231 | iter.pos = -1; | |
4232 | ||
4233 | if (find_next_entry_inc(&iter) != NULL) { | |
4234 | print_trace_line(&iter); | |
4235 | trace_consume(&iter); | |
4236 | } | |
4237 | ||
4238 | trace_printk_seq(&iter.seq); | |
4239 | } | |
4240 | ||
4241 | if (!cnt) | |
4242 | printk(KERN_TRACE " (ftrace buffer empty)\n"); | |
4243 | else | |
4244 | printk(KERN_TRACE "---------------------------------\n"); | |
4245 | ||
cf586b61 FW |
4246 | /* Re-enable tracing if requested */ |
4247 | if (!disable_tracing) { | |
4248 | trace_flags |= old_userobj; | |
4249 | ||
4250 | for_each_tracing_cpu(cpu) { | |
4251 | atomic_dec(&global_trace.data[cpu]->disabled); | |
4252 | } | |
4253 | tracing_on(); | |
4254 | } | |
4255 | ||
3f5a54e3 | 4256 | out: |
cd891ae0 SR |
4257 | __raw_spin_unlock(&ftrace_dump_lock); |
4258 | local_irq_restore(flags); | |
3f5a54e3 SR |
4259 | } |
4260 | ||
cf586b61 FW |
4261 | /* By default: disable tracing after the dump */ |
4262 | void ftrace_dump(void) | |
4263 | { | |
4264 | __ftrace_dump(true); | |
4265 | } | |
4266 | ||
3928a8a2 | 4267 | __init static int tracer_alloc_buffers(void) |
bc0c38d1 | 4268 | { |
4c11d7ae | 4269 | struct trace_array_cpu *data; |
73c5162a | 4270 | int ring_buf_size; |
4c11d7ae | 4271 | int i; |
9e01c1b7 | 4272 | int ret = -ENOMEM; |
4c11d7ae | 4273 | |
9e01c1b7 RR |
4274 | if (!alloc_cpumask_var(&tracing_buffer_mask, GFP_KERNEL)) |
4275 | goto out; | |
4276 | ||
4277 | if (!alloc_cpumask_var(&tracing_cpumask, GFP_KERNEL)) | |
4278 | goto out_free_buffer_mask; | |
4c11d7ae | 4279 | |
b04cc6b1 FW |
4280 | if (!alloc_cpumask_var(&tracing_reader_cpumask, GFP_KERNEL)) |
4281 | goto out_free_tracing_cpumask; | |
4282 | ||
73c5162a SR |
4283 | /* To save memory, keep the ring buffer size to its minimum */ |
4284 | if (ring_buffer_expanded) | |
4285 | ring_buf_size = trace_buf_size; | |
4286 | else | |
4287 | ring_buf_size = 1; | |
4288 | ||
9e01c1b7 RR |
4289 | cpumask_copy(tracing_buffer_mask, cpu_possible_mask); |
4290 | cpumask_copy(tracing_cpumask, cpu_all_mask); | |
b04cc6b1 | 4291 | cpumask_clear(tracing_reader_cpumask); |
9e01c1b7 RR |
4292 | |
4293 | /* TODO: make the number of buffers hot pluggable with CPUS */ | |
73c5162a | 4294 | global_trace.buffer = ring_buffer_alloc(ring_buf_size, |
3928a8a2 SR |
4295 | TRACE_BUFFER_FLAGS); |
4296 | if (!global_trace.buffer) { | |
4297 | printk(KERN_ERR "tracer: failed to allocate ring buffer!\n"); | |
4298 | WARN_ON(1); | |
9e01c1b7 | 4299 | goto out_free_cpumask; |
4c11d7ae | 4300 | } |
3928a8a2 | 4301 | global_trace.entries = ring_buffer_size(global_trace.buffer); |
4c11d7ae | 4302 | |
9e01c1b7 | 4303 | |
4c11d7ae | 4304 | #ifdef CONFIG_TRACER_MAX_TRACE |
73c5162a | 4305 | max_tr.buffer = ring_buffer_alloc(ring_buf_size, |
3928a8a2 SR |
4306 | TRACE_BUFFER_FLAGS); |
4307 | if (!max_tr.buffer) { | |
4308 | printk(KERN_ERR "tracer: failed to allocate max ring buffer!\n"); | |
4309 | WARN_ON(1); | |
4310 | ring_buffer_free(global_trace.buffer); | |
9e01c1b7 | 4311 | goto out_free_cpumask; |
4c11d7ae | 4312 | } |
3928a8a2 SR |
4313 | max_tr.entries = ring_buffer_size(max_tr.buffer); |
4314 | WARN_ON(max_tr.entries != global_trace.entries); | |
a98a3c3f | 4315 | #endif |
ab46428c | 4316 | |
4c11d7ae | 4317 | /* Allocate the first page for all buffers */ |
ab46428c | 4318 | for_each_tracing_cpu(i) { |
4c11d7ae | 4319 | data = global_trace.data[i] = &per_cpu(global_trace_cpu, i); |
bc0c38d1 | 4320 | max_tr.data[i] = &per_cpu(max_data, i); |
4c11d7ae | 4321 | } |
bc0c38d1 | 4322 | |
bc0c38d1 SR |
4323 | trace_init_cmdlines(); |
4324 | ||
43a15386 | 4325 | register_tracer(&nop_trace); |
79fb0768 | 4326 | current_trace = &nop_trace; |
b5ad384e FW |
4327 | #ifdef CONFIG_BOOT_TRACER |
4328 | register_tracer(&boot_tracer); | |
b5ad384e | 4329 | #endif |
60a11774 SR |
4330 | /* All seems OK, enable tracing */ |
4331 | tracing_disabled = 0; | |
3928a8a2 | 4332 | |
3f5a54e3 SR |
4333 | atomic_notifier_chain_register(&panic_notifier_list, |
4334 | &trace_panic_notifier); | |
4335 | ||
4336 | register_die_notifier(&trace_die_notifier); | |
2fc1dfbe FW |
4337 | |
4338 | return 0; | |
3f5a54e3 | 4339 | |
9e01c1b7 | 4340 | out_free_cpumask: |
b04cc6b1 FW |
4341 | free_cpumask_var(tracing_reader_cpumask); |
4342 | out_free_tracing_cpumask: | |
9e01c1b7 RR |
4343 | free_cpumask_var(tracing_cpumask); |
4344 | out_free_buffer_mask: | |
4345 | free_cpumask_var(tracing_buffer_mask); | |
4346 | out: | |
4347 | return ret; | |
bc0c38d1 | 4348 | } |
b2821ae6 SR |
4349 | |
4350 | __init static int clear_boot_tracer(void) | |
4351 | { | |
4352 | /* | |
4353 | * The default tracer at boot buffer is an init section. | |
4354 | * This function is called in lateinit. If we did not | |
4355 | * find the boot tracer, then clear it out, to prevent | |
4356 | * later registration from accessing the buffer that is | |
4357 | * about to be freed. | |
4358 | */ | |
4359 | if (!default_bootup_tracer) | |
4360 | return 0; | |
4361 | ||
4362 | printk(KERN_INFO "ftrace bootup tracer '%s' not registered.\n", | |
4363 | default_bootup_tracer); | |
4364 | default_bootup_tracer = NULL; | |
4365 | ||
4366 | return 0; | |
4367 | } | |
4368 | ||
b5ad384e FW |
4369 | early_initcall(tracer_alloc_buffers); |
4370 | fs_initcall(tracer_init_debugfs); | |
b2821ae6 | 4371 | late_initcall(clear_boot_tracer); |