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Commit | Line | Data |
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bc0c38d1 SR |
1 | /* |
2 | * ring buffer based function tracer | |
3 | * | |
4 | * Copyright (C) 2007-2008 Steven Rostedt <srostedt@redhat.com> | |
5 | * Copyright (C) 2008 Ingo Molnar <mingo@redhat.com> | |
6 | * | |
7 | * Originally taken from the RT patch by: | |
8 | * Arnaldo Carvalho de Melo <acme@redhat.com> | |
9 | * | |
10 | * Based on code from the latency_tracer, that is: | |
11 | * Copyright (C) 2004-2006 Ingo Molnar | |
12 | * Copyright (C) 2004 William Lee Irwin III | |
13 | */ | |
2cadf913 | 14 | #include <linux/ring_buffer.h> |
bc0c38d1 | 15 | #include <linux/utsrelease.h> |
2cadf913 SR |
16 | #include <linux/stacktrace.h> |
17 | #include <linux/writeback.h> | |
bc0c38d1 SR |
18 | #include <linux/kallsyms.h> |
19 | #include <linux/seq_file.h> | |
405f5571 | 20 | #include <linux/smp_lock.h> |
3f5a54e3 | 21 | #include <linux/notifier.h> |
2cadf913 | 22 | #include <linux/irqflags.h> |
bc0c38d1 | 23 | #include <linux/debugfs.h> |
4c11d7ae | 24 | #include <linux/pagemap.h> |
bc0c38d1 SR |
25 | #include <linux/hardirq.h> |
26 | #include <linux/linkage.h> | |
27 | #include <linux/uaccess.h> | |
2cadf913 | 28 | #include <linux/kprobes.h> |
bc0c38d1 SR |
29 | #include <linux/ftrace.h> |
30 | #include <linux/module.h> | |
31 | #include <linux/percpu.h> | |
2cadf913 | 32 | #include <linux/splice.h> |
3f5a54e3 | 33 | #include <linux/kdebug.h> |
5f0c6c03 | 34 | #include <linux/string.h> |
bc0c38d1 SR |
35 | #include <linux/ctype.h> |
36 | #include <linux/init.h> | |
2a2cc8f7 | 37 | #include <linux/poll.h> |
bc0c38d1 SR |
38 | #include <linux/gfp.h> |
39 | #include <linux/fs.h> | |
86387f7e | 40 | |
bc0c38d1 | 41 | #include "trace.h" |
f0868d1e | 42 | #include "trace_output.h" |
bc0c38d1 | 43 | |
3928a8a2 SR |
44 | #define TRACE_BUFFER_FLAGS (RB_FL_OVERWRITE) |
45 | ||
73c5162a SR |
46 | /* |
47 | * On boot up, the ring buffer is set to the minimum size, so that | |
48 | * we do not waste memory on systems that are not using tracing. | |
49 | */ | |
020e5f85 | 50 | int ring_buffer_expanded; |
73c5162a | 51 | |
8e1b82e0 FW |
52 | /* |
53 | * We need to change this state when a selftest is running. | |
ff32504f FW |
54 | * A selftest will lurk into the ring-buffer to count the |
55 | * entries inserted during the selftest although some concurrent | |
5e1607a0 | 56 | * insertions into the ring-buffer such as trace_printk could occurred |
ff32504f FW |
57 | * at the same time, giving false positive or negative results. |
58 | */ | |
8e1b82e0 | 59 | static bool __read_mostly tracing_selftest_running; |
ff32504f | 60 | |
b2821ae6 SR |
61 | /* |
62 | * If a tracer is running, we do not want to run SELFTEST. | |
63 | */ | |
020e5f85 | 64 | bool __read_mostly tracing_selftest_disabled; |
b2821ae6 | 65 | |
adf9f195 FW |
66 | /* For tracers that don't implement custom flags */ |
67 | static struct tracer_opt dummy_tracer_opt[] = { | |
68 | { } | |
69 | }; | |
70 | ||
71 | static struct tracer_flags dummy_tracer_flags = { | |
72 | .val = 0, | |
73 | .opts = dummy_tracer_opt | |
74 | }; | |
75 | ||
76 | static int dummy_set_flag(u32 old_flags, u32 bit, int set) | |
77 | { | |
78 | return 0; | |
79 | } | |
0f048701 SR |
80 | |
81 | /* | |
82 | * Kill all tracing for good (never come back). | |
83 | * It is initialized to 1 but will turn to zero if the initialization | |
84 | * of the tracer is successful. But that is the only place that sets | |
85 | * this back to zero. | |
86 | */ | |
4fd27358 | 87 | static int tracing_disabled = 1; |
0f048701 | 88 | |
5e5bf483 | 89 | DEFINE_PER_CPU(local_t, ftrace_cpu_disabled); |
d769041f SR |
90 | |
91 | static inline void ftrace_disable_cpu(void) | |
92 | { | |
93 | preempt_disable(); | |
94 | local_inc(&__get_cpu_var(ftrace_cpu_disabled)); | |
95 | } | |
96 | ||
97 | static inline void ftrace_enable_cpu(void) | |
98 | { | |
99 | local_dec(&__get_cpu_var(ftrace_cpu_disabled)); | |
100 | preempt_enable(); | |
101 | } | |
102 | ||
9e01c1b7 | 103 | static cpumask_var_t __read_mostly tracing_buffer_mask; |
ab46428c | 104 | |
b04cc6b1 FW |
105 | /* Define which cpu buffers are currently read in trace_pipe */ |
106 | static cpumask_var_t tracing_reader_cpumask; | |
107 | ||
ab46428c | 108 | #define for_each_tracing_cpu(cpu) \ |
9e01c1b7 | 109 | for_each_cpu(cpu, tracing_buffer_mask) |
ab46428c | 110 | |
944ac425 SR |
111 | /* |
112 | * ftrace_dump_on_oops - variable to dump ftrace buffer on oops | |
113 | * | |
114 | * If there is an oops (or kernel panic) and the ftrace_dump_on_oops | |
115 | * is set, then ftrace_dump is called. This will output the contents | |
116 | * of the ftrace buffers to the console. This is very useful for | |
117 | * capturing traces that lead to crashes and outputing it to a | |
118 | * serial console. | |
119 | * | |
120 | * It is default off, but you can enable it with either specifying | |
121 | * "ftrace_dump_on_oops" in the kernel command line, or setting | |
122 | * /proc/sys/kernel/ftrace_dump_on_oops to true. | |
123 | */ | |
124 | int ftrace_dump_on_oops; | |
125 | ||
b2821ae6 SR |
126 | static int tracing_set_tracer(const char *buf); |
127 | ||
128 | #define BOOTUP_TRACER_SIZE 100 | |
129 | static char bootup_tracer_buf[BOOTUP_TRACER_SIZE] __initdata; | |
130 | static char *default_bootup_tracer; | |
d9e54076 PZ |
131 | |
132 | static int __init set_ftrace(char *str) | |
133 | { | |
b2821ae6 SR |
134 | strncpy(bootup_tracer_buf, str, BOOTUP_TRACER_SIZE); |
135 | default_bootup_tracer = bootup_tracer_buf; | |
73c5162a SR |
136 | /* We are using ftrace early, expand it */ |
137 | ring_buffer_expanded = 1; | |
d9e54076 PZ |
138 | return 1; |
139 | } | |
b2821ae6 | 140 | __setup("ftrace=", set_ftrace); |
d9e54076 | 141 | |
944ac425 SR |
142 | static int __init set_ftrace_dump_on_oops(char *str) |
143 | { | |
144 | ftrace_dump_on_oops = 1; | |
145 | return 1; | |
146 | } | |
147 | __setup("ftrace_dump_on_oops", set_ftrace_dump_on_oops); | |
60a11774 | 148 | |
cf8e3474 | 149 | unsigned long long ns2usecs(cycle_t nsec) |
bc0c38d1 SR |
150 | { |
151 | nsec += 500; | |
152 | do_div(nsec, 1000); | |
153 | return nsec; | |
154 | } | |
155 | ||
4fcdae83 SR |
156 | /* |
157 | * The global_trace is the descriptor that holds the tracing | |
158 | * buffers for the live tracing. For each CPU, it contains | |
159 | * a link list of pages that will store trace entries. The | |
160 | * page descriptor of the pages in the memory is used to hold | |
161 | * the link list by linking the lru item in the page descriptor | |
162 | * to each of the pages in the buffer per CPU. | |
163 | * | |
164 | * For each active CPU there is a data field that holds the | |
165 | * pages for the buffer for that CPU. Each CPU has the same number | |
166 | * of pages allocated for its buffer. | |
167 | */ | |
bc0c38d1 SR |
168 | static struct trace_array global_trace; |
169 | ||
170 | static DEFINE_PER_CPU(struct trace_array_cpu, global_trace_cpu); | |
171 | ||
eb02ce01 TZ |
172 | int filter_current_check_discard(struct ftrace_event_call *call, void *rec, |
173 | struct ring_buffer_event *event) | |
174 | { | |
175 | return filter_check_discard(call, rec, global_trace.buffer, event); | |
176 | } | |
17c873ec | 177 | EXPORT_SYMBOL_GPL(filter_current_check_discard); |
eb02ce01 | 178 | |
37886f6a SR |
179 | cycle_t ftrace_now(int cpu) |
180 | { | |
181 | u64 ts; | |
182 | ||
183 | /* Early boot up does not have a buffer yet */ | |
184 | if (!global_trace.buffer) | |
185 | return trace_clock_local(); | |
186 | ||
187 | ts = ring_buffer_time_stamp(global_trace.buffer, cpu); | |
188 | ring_buffer_normalize_time_stamp(global_trace.buffer, cpu, &ts); | |
189 | ||
190 | return ts; | |
191 | } | |
bc0c38d1 | 192 | |
4fcdae83 SR |
193 | /* |
194 | * The max_tr is used to snapshot the global_trace when a maximum | |
195 | * latency is reached. Some tracers will use this to store a maximum | |
196 | * trace while it continues examining live traces. | |
197 | * | |
198 | * The buffers for the max_tr are set up the same as the global_trace. | |
199 | * When a snapshot is taken, the link list of the max_tr is swapped | |
200 | * with the link list of the global_trace and the buffers are reset for | |
201 | * the global_trace so the tracing can continue. | |
202 | */ | |
bc0c38d1 SR |
203 | static struct trace_array max_tr; |
204 | ||
205 | static DEFINE_PER_CPU(struct trace_array_cpu, max_data); | |
206 | ||
4fcdae83 | 207 | /* tracer_enabled is used to toggle activation of a tracer */ |
26994ead | 208 | static int tracer_enabled = 1; |
4fcdae83 | 209 | |
9036990d SR |
210 | /** |
211 | * tracing_is_enabled - return tracer_enabled status | |
212 | * | |
213 | * This function is used by other tracers to know the status | |
214 | * of the tracer_enabled flag. Tracers may use this function | |
215 | * to know if it should enable their features when starting | |
216 | * up. See irqsoff tracer for an example (start_irqsoff_tracer). | |
217 | */ | |
218 | int tracing_is_enabled(void) | |
219 | { | |
220 | return tracer_enabled; | |
221 | } | |
222 | ||
4fcdae83 | 223 | /* |
3928a8a2 SR |
224 | * trace_buf_size is the size in bytes that is allocated |
225 | * for a buffer. Note, the number of bytes is always rounded | |
226 | * to page size. | |
3f5a54e3 SR |
227 | * |
228 | * This number is purposely set to a low number of 16384. | |
229 | * If the dump on oops happens, it will be much appreciated | |
230 | * to not have to wait for all that output. Anyway this can be | |
231 | * boot time and run time configurable. | |
4fcdae83 | 232 | */ |
3928a8a2 | 233 | #define TRACE_BUF_SIZE_DEFAULT 1441792UL /* 16384 * 88 (sizeof(entry)) */ |
3f5a54e3 | 234 | |
3928a8a2 | 235 | static unsigned long trace_buf_size = TRACE_BUF_SIZE_DEFAULT; |
bc0c38d1 | 236 | |
4fcdae83 | 237 | /* trace_types holds a link list of available tracers. */ |
bc0c38d1 | 238 | static struct tracer *trace_types __read_mostly; |
4fcdae83 SR |
239 | |
240 | /* current_trace points to the tracer that is currently active */ | |
bc0c38d1 | 241 | static struct tracer *current_trace __read_mostly; |
4fcdae83 SR |
242 | |
243 | /* | |
244 | * max_tracer_type_len is used to simplify the allocating of | |
245 | * buffers to read userspace tracer names. We keep track of | |
246 | * the longest tracer name registered. | |
247 | */ | |
bc0c38d1 SR |
248 | static int max_tracer_type_len; |
249 | ||
4fcdae83 SR |
250 | /* |
251 | * trace_types_lock is used to protect the trace_types list. | |
252 | * This lock is also used to keep user access serialized. | |
253 | * Accesses from userspace will grab this lock while userspace | |
254 | * activities happen inside the kernel. | |
255 | */ | |
bc0c38d1 | 256 | static DEFINE_MUTEX(trace_types_lock); |
4fcdae83 SR |
257 | |
258 | /* trace_wait is a waitqueue for tasks blocked on trace_poll */ | |
4e655519 IM |
259 | static DECLARE_WAIT_QUEUE_HEAD(trace_wait); |
260 | ||
ee6bce52 | 261 | /* trace_flags holds trace_options default values */ |
12ef7d44 | 262 | unsigned long trace_flags = TRACE_ITER_PRINT_PARENT | TRACE_ITER_PRINTK | |
a2a16d6a SR |
263 | TRACE_ITER_ANNOTATE | TRACE_ITER_CONTEXT_INFO | TRACE_ITER_SLEEP_TIME | |
264 | TRACE_ITER_GRAPH_TIME; | |
4e655519 | 265 | |
4fcdae83 SR |
266 | /** |
267 | * trace_wake_up - wake up tasks waiting for trace input | |
268 | * | |
269 | * Simply wakes up any task that is blocked on the trace_wait | |
270 | * queue. These is used with trace_poll for tasks polling the trace. | |
271 | */ | |
4e655519 IM |
272 | void trace_wake_up(void) |
273 | { | |
017730c1 IM |
274 | /* |
275 | * The runqueue_is_locked() can fail, but this is the best we | |
276 | * have for now: | |
277 | */ | |
278 | if (!(trace_flags & TRACE_ITER_BLOCK) && !runqueue_is_locked()) | |
4e655519 IM |
279 | wake_up(&trace_wait); |
280 | } | |
bc0c38d1 | 281 | |
3928a8a2 | 282 | static int __init set_buf_size(char *str) |
bc0c38d1 | 283 | { |
3928a8a2 | 284 | unsigned long buf_size; |
c6caeeb1 | 285 | |
bc0c38d1 SR |
286 | if (!str) |
287 | return 0; | |
9d612bef | 288 | buf_size = memparse(str, &str); |
c6caeeb1 | 289 | /* nr_entries can not be zero */ |
9d612bef | 290 | if (buf_size == 0) |
c6caeeb1 | 291 | return 0; |
3928a8a2 | 292 | trace_buf_size = buf_size; |
bc0c38d1 SR |
293 | return 1; |
294 | } | |
3928a8a2 | 295 | __setup("trace_buf_size=", set_buf_size); |
bc0c38d1 | 296 | |
57f50be1 SR |
297 | unsigned long nsecs_to_usecs(unsigned long nsecs) |
298 | { | |
299 | return nsecs / 1000; | |
300 | } | |
301 | ||
4fcdae83 | 302 | /* These must match the bit postions in trace_iterator_flags */ |
bc0c38d1 SR |
303 | static const char *trace_options[] = { |
304 | "print-parent", | |
305 | "sym-offset", | |
306 | "sym-addr", | |
307 | "verbose", | |
f9896bf3 | 308 | "raw", |
5e3ca0ec | 309 | "hex", |
cb0f12aa | 310 | "bin", |
2a2cc8f7 | 311 | "block", |
86387f7e | 312 | "stacktrace", |
4ac3ba41 | 313 | "sched-tree", |
5e1607a0 | 314 | "trace_printk", |
b2a866f9 | 315 | "ftrace_preempt", |
9f029e83 | 316 | "branch", |
12ef7d44 | 317 | "annotate", |
02b67518 | 318 | "userstacktrace", |
b54d3de9 | 319 | "sym-userobj", |
66896a85 | 320 | "printk-msg-only", |
c4a8e8be | 321 | "context-info", |
c032ef64 | 322 | "latency-format", |
be6f164a | 323 | "sleep-time", |
a2a16d6a | 324 | "graph-time", |
bc0c38d1 SR |
325 | NULL |
326 | }; | |
327 | ||
5079f326 Z |
328 | static struct { |
329 | u64 (*func)(void); | |
330 | const char *name; | |
331 | } trace_clocks[] = { | |
332 | { trace_clock_local, "local" }, | |
333 | { trace_clock_global, "global" }, | |
334 | }; | |
335 | ||
336 | int trace_clock_id; | |
337 | ||
6c6c2796 PP |
338 | ssize_t trace_seq_to_user(struct trace_seq *s, char __user *ubuf, size_t cnt) |
339 | { | |
340 | int len; | |
341 | int ret; | |
342 | ||
2dc5d12b SR |
343 | if (!cnt) |
344 | return 0; | |
345 | ||
6c6c2796 PP |
346 | if (s->len <= s->readpos) |
347 | return -EBUSY; | |
348 | ||
349 | len = s->len - s->readpos; | |
350 | if (cnt > len) | |
351 | cnt = len; | |
352 | ret = copy_to_user(ubuf, s->buffer + s->readpos, cnt); | |
2dc5d12b | 353 | if (ret == cnt) |
6c6c2796 PP |
354 | return -EFAULT; |
355 | ||
2dc5d12b SR |
356 | cnt -= ret; |
357 | ||
e74da523 | 358 | s->readpos += cnt; |
6c6c2796 | 359 | return cnt; |
214023c3 SR |
360 | } |
361 | ||
b8b94265 | 362 | static ssize_t trace_seq_to_buffer(struct trace_seq *s, void *buf, size_t cnt) |
3c56819b EGM |
363 | { |
364 | int len; | |
365 | void *ret; | |
366 | ||
367 | if (s->len <= s->readpos) | |
368 | return -EBUSY; | |
369 | ||
370 | len = s->len - s->readpos; | |
371 | if (cnt > len) | |
372 | cnt = len; | |
373 | ret = memcpy(buf, s->buffer + s->readpos, cnt); | |
374 | if (!ret) | |
375 | return -EFAULT; | |
376 | ||
e74da523 | 377 | s->readpos += cnt; |
3c56819b EGM |
378 | return cnt; |
379 | } | |
380 | ||
5d4a9dba SR |
381 | /* |
382 | * ftrace_max_lock is used to protect the swapping of buffers | |
383 | * when taking a max snapshot. The buffers themselves are | |
384 | * protected by per_cpu spinlocks. But the action of the swap | |
385 | * needs its own lock. | |
386 | * | |
387 | * This is defined as a raw_spinlock_t in order to help | |
388 | * with performance when lockdep debugging is enabled. | |
389 | * | |
390 | * It is also used in other places outside the update_max_tr | |
391 | * so it needs to be defined outside of the | |
392 | * CONFIG_TRACER_MAX_TRACE. | |
393 | */ | |
394 | static raw_spinlock_t ftrace_max_lock = | |
395 | (raw_spinlock_t)__RAW_SPIN_LOCK_UNLOCKED; | |
396 | ||
397 | #ifdef CONFIG_TRACER_MAX_TRACE | |
398 | unsigned long __read_mostly tracing_max_latency; | |
399 | unsigned long __read_mostly tracing_thresh; | |
400 | ||
401 | /* | |
402 | * Copy the new maximum trace into the separate maximum-trace | |
403 | * structure. (this way the maximum trace is permanently saved, | |
404 | * for later retrieval via /sys/kernel/debug/tracing/latency_trace) | |
405 | */ | |
406 | static void | |
407 | __update_max_tr(struct trace_array *tr, struct task_struct *tsk, int cpu) | |
408 | { | |
409 | struct trace_array_cpu *data = tr->data[cpu]; | |
410 | ||
411 | max_tr.cpu = cpu; | |
412 | max_tr.time_start = data->preempt_timestamp; | |
413 | ||
414 | data = max_tr.data[cpu]; | |
415 | data->saved_latency = tracing_max_latency; | |
416 | ||
417 | memcpy(data->comm, tsk->comm, TASK_COMM_LEN); | |
418 | data->pid = tsk->pid; | |
419 | data->uid = task_uid(tsk); | |
420 | data->nice = tsk->static_prio - 20 - MAX_RT_PRIO; | |
421 | data->policy = tsk->policy; | |
422 | data->rt_priority = tsk->rt_priority; | |
423 | ||
424 | /* record this tasks comm */ | |
425 | tracing_record_cmdline(tsk); | |
426 | } | |
427 | ||
4fcdae83 SR |
428 | /** |
429 | * update_max_tr - snapshot all trace buffers from global_trace to max_tr | |
430 | * @tr: tracer | |
431 | * @tsk: the task with the latency | |
432 | * @cpu: The cpu that initiated the trace. | |
433 | * | |
434 | * Flip the buffers between the @tr and the max_tr and record information | |
435 | * about which task was the cause of this latency. | |
436 | */ | |
e309b41d | 437 | void |
bc0c38d1 SR |
438 | update_max_tr(struct trace_array *tr, struct task_struct *tsk, int cpu) |
439 | { | |
3928a8a2 | 440 | struct ring_buffer *buf = tr->buffer; |
bc0c38d1 | 441 | |
4c11d7ae | 442 | WARN_ON_ONCE(!irqs_disabled()); |
92205c23 | 443 | __raw_spin_lock(&ftrace_max_lock); |
3928a8a2 SR |
444 | |
445 | tr->buffer = max_tr.buffer; | |
446 | max_tr.buffer = buf; | |
447 | ||
d769041f | 448 | ftrace_disable_cpu(); |
3928a8a2 | 449 | ring_buffer_reset(tr->buffer); |
d769041f | 450 | ftrace_enable_cpu(); |
bc0c38d1 SR |
451 | |
452 | __update_max_tr(tr, tsk, cpu); | |
92205c23 | 453 | __raw_spin_unlock(&ftrace_max_lock); |
bc0c38d1 SR |
454 | } |
455 | ||
456 | /** | |
457 | * update_max_tr_single - only copy one trace over, and reset the rest | |
458 | * @tr - tracer | |
459 | * @tsk - task with the latency | |
460 | * @cpu - the cpu of the buffer to copy. | |
4fcdae83 SR |
461 | * |
462 | * Flip the trace of a single CPU buffer between the @tr and the max_tr. | |
bc0c38d1 | 463 | */ |
e309b41d | 464 | void |
bc0c38d1 SR |
465 | update_max_tr_single(struct trace_array *tr, struct task_struct *tsk, int cpu) |
466 | { | |
3928a8a2 | 467 | int ret; |
bc0c38d1 | 468 | |
4c11d7ae | 469 | WARN_ON_ONCE(!irqs_disabled()); |
92205c23 | 470 | __raw_spin_lock(&ftrace_max_lock); |
bc0c38d1 | 471 | |
d769041f SR |
472 | ftrace_disable_cpu(); |
473 | ||
3928a8a2 SR |
474 | ring_buffer_reset(max_tr.buffer); |
475 | ret = ring_buffer_swap_cpu(max_tr.buffer, tr->buffer, cpu); | |
476 | ||
d769041f SR |
477 | ftrace_enable_cpu(); |
478 | ||
97b17efe | 479 | WARN_ON_ONCE(ret && ret != -EAGAIN); |
bc0c38d1 SR |
480 | |
481 | __update_max_tr(tr, tsk, cpu); | |
92205c23 | 482 | __raw_spin_unlock(&ftrace_max_lock); |
bc0c38d1 | 483 | } |
5d4a9dba | 484 | #endif /* CONFIG_TRACER_MAX_TRACE */ |
bc0c38d1 | 485 | |
4fcdae83 SR |
486 | /** |
487 | * register_tracer - register a tracer with the ftrace system. | |
488 | * @type - the plugin for the tracer | |
489 | * | |
490 | * Register a new plugin tracer. | |
491 | */ | |
bc0c38d1 | 492 | int register_tracer(struct tracer *type) |
e7669b8e HE |
493 | __releases(kernel_lock) |
494 | __acquires(kernel_lock) | |
bc0c38d1 SR |
495 | { |
496 | struct tracer *t; | |
497 | int len; | |
498 | int ret = 0; | |
499 | ||
500 | if (!type->name) { | |
501 | pr_info("Tracer must have a name\n"); | |
502 | return -1; | |
503 | } | |
504 | ||
86fa2f60 IM |
505 | /* |
506 | * When this gets called we hold the BKL which means that | |
507 | * preemption is disabled. Various trace selftests however | |
508 | * need to disable and enable preemption for successful tests. | |
509 | * So we drop the BKL here and grab it after the tests again. | |
510 | */ | |
511 | unlock_kernel(); | |
bc0c38d1 | 512 | mutex_lock(&trace_types_lock); |
86fa2f60 | 513 | |
8e1b82e0 FW |
514 | tracing_selftest_running = true; |
515 | ||
bc0c38d1 SR |
516 | for (t = trace_types; t; t = t->next) { |
517 | if (strcmp(type->name, t->name) == 0) { | |
518 | /* already found */ | |
519 | pr_info("Trace %s already registered\n", | |
520 | type->name); | |
521 | ret = -1; | |
522 | goto out; | |
523 | } | |
524 | } | |
525 | ||
adf9f195 FW |
526 | if (!type->set_flag) |
527 | type->set_flag = &dummy_set_flag; | |
528 | if (!type->flags) | |
529 | type->flags = &dummy_tracer_flags; | |
530 | else | |
531 | if (!type->flags->opts) | |
532 | type->flags->opts = dummy_tracer_opt; | |
6eaaa5d5 FW |
533 | if (!type->wait_pipe) |
534 | type->wait_pipe = default_wait_pipe; | |
535 | ||
adf9f195 | 536 | |
60a11774 | 537 | #ifdef CONFIG_FTRACE_STARTUP_TEST |
b2821ae6 | 538 | if (type->selftest && !tracing_selftest_disabled) { |
60a11774 | 539 | struct tracer *saved_tracer = current_trace; |
60a11774 | 540 | struct trace_array *tr = &global_trace; |
60a11774 | 541 | int i; |
ff32504f | 542 | |
60a11774 SR |
543 | /* |
544 | * Run a selftest on this tracer. | |
545 | * Here we reset the trace buffer, and set the current | |
546 | * tracer to be this tracer. The tracer can then run some | |
547 | * internal tracing to verify that everything is in order. | |
548 | * If we fail, we do not register this tracer. | |
549 | */ | |
86fa2f60 | 550 | for_each_tracing_cpu(i) |
3928a8a2 | 551 | tracing_reset(tr, i); |
86fa2f60 | 552 | |
60a11774 | 553 | current_trace = type; |
60a11774 SR |
554 | /* the test is responsible for initializing and enabling */ |
555 | pr_info("Testing tracer %s: ", type->name); | |
556 | ret = type->selftest(type, tr); | |
557 | /* the test is responsible for resetting too */ | |
558 | current_trace = saved_tracer; | |
60a11774 SR |
559 | if (ret) { |
560 | printk(KERN_CONT "FAILED!\n"); | |
561 | goto out; | |
562 | } | |
1d4db00a | 563 | /* Only reset on passing, to avoid touching corrupted buffers */ |
86fa2f60 | 564 | for_each_tracing_cpu(i) |
3928a8a2 | 565 | tracing_reset(tr, i); |
86fa2f60 | 566 | |
60a11774 SR |
567 | printk(KERN_CONT "PASSED\n"); |
568 | } | |
569 | #endif | |
570 | ||
bc0c38d1 SR |
571 | type->next = trace_types; |
572 | trace_types = type; | |
573 | len = strlen(type->name); | |
574 | if (len > max_tracer_type_len) | |
575 | max_tracer_type_len = len; | |
60a11774 | 576 | |
bc0c38d1 | 577 | out: |
8e1b82e0 | 578 | tracing_selftest_running = false; |
bc0c38d1 SR |
579 | mutex_unlock(&trace_types_lock); |
580 | ||
dac74940 SR |
581 | if (ret || !default_bootup_tracer) |
582 | goto out_unlock; | |
583 | ||
584 | if (strncmp(default_bootup_tracer, type->name, BOOTUP_TRACER_SIZE)) | |
585 | goto out_unlock; | |
586 | ||
587 | printk(KERN_INFO "Starting tracer '%s'\n", type->name); | |
588 | /* Do we want this tracer to start on bootup? */ | |
589 | tracing_set_tracer(type->name); | |
590 | default_bootup_tracer = NULL; | |
591 | /* disable other selftests, since this will break it. */ | |
592 | tracing_selftest_disabled = 1; | |
b2821ae6 | 593 | #ifdef CONFIG_FTRACE_STARTUP_TEST |
dac74940 SR |
594 | printk(KERN_INFO "Disabling FTRACE selftests due to running tracer '%s'\n", |
595 | type->name); | |
b2821ae6 | 596 | #endif |
b2821ae6 | 597 | |
dac74940 | 598 | out_unlock: |
b2821ae6 | 599 | lock_kernel(); |
bc0c38d1 SR |
600 | return ret; |
601 | } | |
602 | ||
603 | void unregister_tracer(struct tracer *type) | |
604 | { | |
605 | struct tracer **t; | |
606 | int len; | |
607 | ||
608 | mutex_lock(&trace_types_lock); | |
609 | for (t = &trace_types; *t; t = &(*t)->next) { | |
610 | if (*t == type) | |
611 | goto found; | |
612 | } | |
613 | pr_info("Trace %s not registered\n", type->name); | |
614 | goto out; | |
615 | ||
616 | found: | |
617 | *t = (*t)->next; | |
b5db03c4 ACM |
618 | |
619 | if (type == current_trace && tracer_enabled) { | |
620 | tracer_enabled = 0; | |
621 | tracing_stop(); | |
622 | if (current_trace->stop) | |
623 | current_trace->stop(&global_trace); | |
624 | current_trace = &nop_trace; | |
625 | } | |
626 | ||
bc0c38d1 SR |
627 | if (strlen(type->name) != max_tracer_type_len) |
628 | goto out; | |
629 | ||
630 | max_tracer_type_len = 0; | |
631 | for (t = &trace_types; *t; t = &(*t)->next) { | |
632 | len = strlen((*t)->name); | |
633 | if (len > max_tracer_type_len) | |
634 | max_tracer_type_len = len; | |
635 | } | |
636 | out: | |
637 | mutex_unlock(&trace_types_lock); | |
638 | } | |
639 | ||
3928a8a2 | 640 | void tracing_reset(struct trace_array *tr, int cpu) |
bc0c38d1 | 641 | { |
d769041f | 642 | ftrace_disable_cpu(); |
3928a8a2 | 643 | ring_buffer_reset_cpu(tr->buffer, cpu); |
d769041f | 644 | ftrace_enable_cpu(); |
bc0c38d1 SR |
645 | } |
646 | ||
213cc060 PE |
647 | void tracing_reset_online_cpus(struct trace_array *tr) |
648 | { | |
649 | int cpu; | |
650 | ||
651 | tr->time_start = ftrace_now(tr->cpu); | |
652 | ||
653 | for_each_online_cpu(cpu) | |
654 | tracing_reset(tr, cpu); | |
655 | } | |
656 | ||
9456f0fa SR |
657 | void tracing_reset_current(int cpu) |
658 | { | |
659 | tracing_reset(&global_trace, cpu); | |
660 | } | |
661 | ||
662 | void tracing_reset_current_online_cpus(void) | |
663 | { | |
664 | tracing_reset_online_cpus(&global_trace); | |
665 | } | |
666 | ||
bc0c38d1 | 667 | #define SAVED_CMDLINES 128 |
2c7eea4c | 668 | #define NO_CMDLINE_MAP UINT_MAX |
bc0c38d1 SR |
669 | static unsigned map_pid_to_cmdline[PID_MAX_DEFAULT+1]; |
670 | static unsigned map_cmdline_to_pid[SAVED_CMDLINES]; | |
671 | static char saved_cmdlines[SAVED_CMDLINES][TASK_COMM_LEN]; | |
672 | static int cmdline_idx; | |
efed792d | 673 | static raw_spinlock_t trace_cmdline_lock = __RAW_SPIN_LOCK_UNLOCKED; |
25b0b44a | 674 | |
25b0b44a | 675 | /* temporary disable recording */ |
4fd27358 | 676 | static atomic_t trace_record_cmdline_disabled __read_mostly; |
bc0c38d1 SR |
677 | |
678 | static void trace_init_cmdlines(void) | |
679 | { | |
2c7eea4c TG |
680 | memset(&map_pid_to_cmdline, NO_CMDLINE_MAP, sizeof(map_pid_to_cmdline)); |
681 | memset(&map_cmdline_to_pid, NO_CMDLINE_MAP, sizeof(map_cmdline_to_pid)); | |
bc0c38d1 SR |
682 | cmdline_idx = 0; |
683 | } | |
684 | ||
0f048701 SR |
685 | static int trace_stop_count; |
686 | static DEFINE_SPINLOCK(tracing_start_lock); | |
687 | ||
69bb54ec SR |
688 | /** |
689 | * ftrace_off_permanent - disable all ftrace code permanently | |
690 | * | |
691 | * This should only be called when a serious anomally has | |
692 | * been detected. This will turn off the function tracing, | |
693 | * ring buffers, and other tracing utilites. It takes no | |
694 | * locks and can be called from any context. | |
695 | */ | |
696 | void ftrace_off_permanent(void) | |
697 | { | |
698 | tracing_disabled = 1; | |
699 | ftrace_stop(); | |
700 | tracing_off_permanent(); | |
701 | } | |
702 | ||
0f048701 SR |
703 | /** |
704 | * tracing_start - quick start of the tracer | |
705 | * | |
706 | * If tracing is enabled but was stopped by tracing_stop, | |
707 | * this will start the tracer back up. | |
708 | */ | |
709 | void tracing_start(void) | |
710 | { | |
711 | struct ring_buffer *buffer; | |
712 | unsigned long flags; | |
713 | ||
714 | if (tracing_disabled) | |
715 | return; | |
716 | ||
717 | spin_lock_irqsave(&tracing_start_lock, flags); | |
b06a8301 SR |
718 | if (--trace_stop_count) { |
719 | if (trace_stop_count < 0) { | |
720 | /* Someone screwed up their debugging */ | |
721 | WARN_ON_ONCE(1); | |
722 | trace_stop_count = 0; | |
723 | } | |
0f048701 SR |
724 | goto out; |
725 | } | |
726 | ||
727 | ||
728 | buffer = global_trace.buffer; | |
729 | if (buffer) | |
730 | ring_buffer_record_enable(buffer); | |
731 | ||
732 | buffer = max_tr.buffer; | |
733 | if (buffer) | |
734 | ring_buffer_record_enable(buffer); | |
735 | ||
736 | ftrace_start(); | |
737 | out: | |
738 | spin_unlock_irqrestore(&tracing_start_lock, flags); | |
739 | } | |
740 | ||
741 | /** | |
742 | * tracing_stop - quick stop of the tracer | |
743 | * | |
744 | * Light weight way to stop tracing. Use in conjunction with | |
745 | * tracing_start. | |
746 | */ | |
747 | void tracing_stop(void) | |
748 | { | |
749 | struct ring_buffer *buffer; | |
750 | unsigned long flags; | |
751 | ||
752 | ftrace_stop(); | |
753 | spin_lock_irqsave(&tracing_start_lock, flags); | |
754 | if (trace_stop_count++) | |
755 | goto out; | |
756 | ||
757 | buffer = global_trace.buffer; | |
758 | if (buffer) | |
759 | ring_buffer_record_disable(buffer); | |
760 | ||
761 | buffer = max_tr.buffer; | |
762 | if (buffer) | |
763 | ring_buffer_record_disable(buffer); | |
764 | ||
765 | out: | |
766 | spin_unlock_irqrestore(&tracing_start_lock, flags); | |
767 | } | |
768 | ||
e309b41d | 769 | void trace_stop_cmdline_recording(void); |
bc0c38d1 | 770 | |
e309b41d | 771 | static void trace_save_cmdline(struct task_struct *tsk) |
bc0c38d1 | 772 | { |
a635cf04 | 773 | unsigned pid, idx; |
bc0c38d1 SR |
774 | |
775 | if (!tsk->pid || unlikely(tsk->pid > PID_MAX_DEFAULT)) | |
776 | return; | |
777 | ||
778 | /* | |
779 | * It's not the end of the world if we don't get | |
780 | * the lock, but we also don't want to spin | |
781 | * nor do we want to disable interrupts, | |
782 | * so if we miss here, then better luck next time. | |
783 | */ | |
efed792d | 784 | if (!__raw_spin_trylock(&trace_cmdline_lock)) |
bc0c38d1 SR |
785 | return; |
786 | ||
787 | idx = map_pid_to_cmdline[tsk->pid]; | |
2c7eea4c | 788 | if (idx == NO_CMDLINE_MAP) { |
bc0c38d1 SR |
789 | idx = (cmdline_idx + 1) % SAVED_CMDLINES; |
790 | ||
a635cf04 CE |
791 | /* |
792 | * Check whether the cmdline buffer at idx has a pid | |
793 | * mapped. We are going to overwrite that entry so we | |
794 | * need to clear the map_pid_to_cmdline. Otherwise we | |
795 | * would read the new comm for the old pid. | |
796 | */ | |
797 | pid = map_cmdline_to_pid[idx]; | |
798 | if (pid != NO_CMDLINE_MAP) | |
799 | map_pid_to_cmdline[pid] = NO_CMDLINE_MAP; | |
bc0c38d1 | 800 | |
a635cf04 | 801 | map_cmdline_to_pid[idx] = tsk->pid; |
bc0c38d1 SR |
802 | map_pid_to_cmdline[tsk->pid] = idx; |
803 | ||
804 | cmdline_idx = idx; | |
805 | } | |
806 | ||
807 | memcpy(&saved_cmdlines[idx], tsk->comm, TASK_COMM_LEN); | |
808 | ||
efed792d | 809 | __raw_spin_unlock(&trace_cmdline_lock); |
bc0c38d1 SR |
810 | } |
811 | ||
4ca53085 | 812 | void trace_find_cmdline(int pid, char comm[]) |
bc0c38d1 | 813 | { |
bc0c38d1 SR |
814 | unsigned map; |
815 | ||
4ca53085 SR |
816 | if (!pid) { |
817 | strcpy(comm, "<idle>"); | |
818 | return; | |
819 | } | |
bc0c38d1 | 820 | |
4ca53085 SR |
821 | if (pid > PID_MAX_DEFAULT) { |
822 | strcpy(comm, "<...>"); | |
823 | return; | |
824 | } | |
bc0c38d1 | 825 | |
5b6045a9 | 826 | preempt_disable(); |
4ca53085 | 827 | __raw_spin_lock(&trace_cmdline_lock); |
bc0c38d1 | 828 | map = map_pid_to_cmdline[pid]; |
50d88758 TG |
829 | if (map != NO_CMDLINE_MAP) |
830 | strcpy(comm, saved_cmdlines[map]); | |
831 | else | |
832 | strcpy(comm, "<...>"); | |
bc0c38d1 | 833 | |
4ca53085 | 834 | __raw_spin_unlock(&trace_cmdline_lock); |
5b6045a9 | 835 | preempt_enable(); |
bc0c38d1 SR |
836 | } |
837 | ||
e309b41d | 838 | void tracing_record_cmdline(struct task_struct *tsk) |
bc0c38d1 | 839 | { |
18aecd36 TG |
840 | if (atomic_read(&trace_record_cmdline_disabled) || !tracer_enabled || |
841 | !tracing_is_on()) | |
bc0c38d1 SR |
842 | return; |
843 | ||
844 | trace_save_cmdline(tsk); | |
845 | } | |
846 | ||
45dcd8b8 | 847 | void |
38697053 SR |
848 | tracing_generic_entry_update(struct trace_entry *entry, unsigned long flags, |
849 | int pc) | |
bc0c38d1 SR |
850 | { |
851 | struct task_struct *tsk = current; | |
bc0c38d1 | 852 | |
777e208d SR |
853 | entry->preempt_count = pc & 0xff; |
854 | entry->pid = (tsk) ? tsk->pid : 0; | |
ef18012b | 855 | entry->tgid = (tsk) ? tsk->tgid : 0; |
777e208d | 856 | entry->flags = |
9244489a | 857 | #ifdef CONFIG_TRACE_IRQFLAGS_SUPPORT |
2e2ca155 | 858 | (irqs_disabled_flags(flags) ? TRACE_FLAG_IRQS_OFF : 0) | |
9244489a SR |
859 | #else |
860 | TRACE_FLAG_IRQS_NOSUPPORT | | |
861 | #endif | |
bc0c38d1 SR |
862 | ((pc & HARDIRQ_MASK) ? TRACE_FLAG_HARDIRQ : 0) | |
863 | ((pc & SOFTIRQ_MASK) ? TRACE_FLAG_SOFTIRQ : 0) | | |
864 | (need_resched() ? TRACE_FLAG_NEED_RESCHED : 0); | |
865 | } | |
f413cdb8 | 866 | EXPORT_SYMBOL_GPL(tracing_generic_entry_update); |
bc0c38d1 | 867 | |
51a763dd | 868 | struct ring_buffer_event *trace_buffer_lock_reserve(struct trace_array *tr, |
7a4f453b | 869 | int type, |
51a763dd ACM |
870 | unsigned long len, |
871 | unsigned long flags, int pc) | |
872 | { | |
873 | struct ring_buffer_event *event; | |
874 | ||
875 | event = ring_buffer_lock_reserve(tr->buffer, len); | |
876 | if (event != NULL) { | |
877 | struct trace_entry *ent = ring_buffer_event_data(event); | |
878 | ||
879 | tracing_generic_entry_update(ent, flags, pc); | |
880 | ent->type = type; | |
881 | } | |
882 | ||
883 | return event; | |
884 | } | |
51a763dd | 885 | |
07edf712 FW |
886 | static inline void __trace_buffer_unlock_commit(struct trace_array *tr, |
887 | struct ring_buffer_event *event, | |
888 | unsigned long flags, int pc, | |
889 | int wake) | |
51a763dd ACM |
890 | { |
891 | ring_buffer_unlock_commit(tr->buffer, event); | |
892 | ||
893 | ftrace_trace_stack(tr, flags, 6, pc); | |
894 | ftrace_trace_userstack(tr, flags, pc); | |
07edf712 FW |
895 | |
896 | if (wake) | |
897 | trace_wake_up(); | |
898 | } | |
899 | ||
900 | void trace_buffer_unlock_commit(struct trace_array *tr, | |
901 | struct ring_buffer_event *event, | |
902 | unsigned long flags, int pc) | |
903 | { | |
904 | __trace_buffer_unlock_commit(tr, event, flags, pc, 1); | |
51a763dd ACM |
905 | } |
906 | ||
ef5580d0 | 907 | struct ring_buffer_event * |
7a4f453b | 908 | trace_current_buffer_lock_reserve(int type, unsigned long len, |
ef5580d0 SR |
909 | unsigned long flags, int pc) |
910 | { | |
911 | return trace_buffer_lock_reserve(&global_trace, | |
912 | type, len, flags, pc); | |
913 | } | |
94487d6d | 914 | EXPORT_SYMBOL_GPL(trace_current_buffer_lock_reserve); |
ef5580d0 SR |
915 | |
916 | void trace_current_buffer_unlock_commit(struct ring_buffer_event *event, | |
917 | unsigned long flags, int pc) | |
918 | { | |
77d9f465 | 919 | __trace_buffer_unlock_commit(&global_trace, event, flags, pc, 1); |
07edf712 | 920 | } |
94487d6d | 921 | EXPORT_SYMBOL_GPL(trace_current_buffer_unlock_commit); |
07edf712 FW |
922 | |
923 | void trace_nowake_buffer_unlock_commit(struct ring_buffer_event *event, | |
924 | unsigned long flags, int pc) | |
925 | { | |
77d9f465 SR |
926 | __trace_buffer_unlock_commit(&global_trace, event, flags, pc, 0); |
927 | } | |
94487d6d | 928 | EXPORT_SYMBOL_GPL(trace_nowake_buffer_unlock_commit); |
77d9f465 SR |
929 | |
930 | void trace_current_buffer_discard_commit(struct ring_buffer_event *event) | |
931 | { | |
932 | ring_buffer_discard_commit(global_trace.buffer, event); | |
ef5580d0 | 933 | } |
12acd473 | 934 | EXPORT_SYMBOL_GPL(trace_current_buffer_discard_commit); |
ef5580d0 | 935 | |
e309b41d | 936 | void |
7be42151 | 937 | trace_function(struct trace_array *tr, |
38697053 SR |
938 | unsigned long ip, unsigned long parent_ip, unsigned long flags, |
939 | int pc) | |
bc0c38d1 | 940 | { |
e1112b4d | 941 | struct ftrace_event_call *call = &event_function; |
3928a8a2 | 942 | struct ring_buffer_event *event; |
777e208d | 943 | struct ftrace_entry *entry; |
bc0c38d1 | 944 | |
d769041f SR |
945 | /* If we are reading the ring buffer, don't trace */ |
946 | if (unlikely(local_read(&__get_cpu_var(ftrace_cpu_disabled)))) | |
947 | return; | |
948 | ||
51a763dd ACM |
949 | event = trace_buffer_lock_reserve(tr, TRACE_FN, sizeof(*entry), |
950 | flags, pc); | |
3928a8a2 SR |
951 | if (!event) |
952 | return; | |
953 | entry = ring_buffer_event_data(event); | |
777e208d SR |
954 | entry->ip = ip; |
955 | entry->parent_ip = parent_ip; | |
e1112b4d | 956 | |
eb02ce01 TZ |
957 | if (!filter_check_discard(call, entry, tr->buffer, event)) |
958 | ring_buffer_unlock_commit(tr->buffer, event); | |
bc0c38d1 SR |
959 | } |
960 | ||
e309b41d | 961 | void |
2e0f5761 | 962 | ftrace(struct trace_array *tr, struct trace_array_cpu *data, |
38697053 SR |
963 | unsigned long ip, unsigned long parent_ip, unsigned long flags, |
964 | int pc) | |
2e0f5761 IM |
965 | { |
966 | if (likely(!atomic_read(&data->disabled))) | |
7be42151 | 967 | trace_function(tr, ip, parent_ip, flags, pc); |
2e0f5761 IM |
968 | } |
969 | ||
c0a0d0d3 | 970 | #ifdef CONFIG_STACKTRACE |
53614991 | 971 | static void __ftrace_trace_stack(struct trace_array *tr, |
53614991 SR |
972 | unsigned long flags, |
973 | int skip, int pc) | |
86387f7e | 974 | { |
e1112b4d | 975 | struct ftrace_event_call *call = &event_kernel_stack; |
3928a8a2 | 976 | struct ring_buffer_event *event; |
777e208d | 977 | struct stack_entry *entry; |
86387f7e IM |
978 | struct stack_trace trace; |
979 | ||
51a763dd ACM |
980 | event = trace_buffer_lock_reserve(tr, TRACE_STACK, |
981 | sizeof(*entry), flags, pc); | |
3928a8a2 SR |
982 | if (!event) |
983 | return; | |
984 | entry = ring_buffer_event_data(event); | |
777e208d | 985 | memset(&entry->caller, 0, sizeof(entry->caller)); |
86387f7e IM |
986 | |
987 | trace.nr_entries = 0; | |
988 | trace.max_entries = FTRACE_STACK_ENTRIES; | |
989 | trace.skip = skip; | |
777e208d | 990 | trace.entries = entry->caller; |
86387f7e IM |
991 | |
992 | save_stack_trace(&trace); | |
eb02ce01 TZ |
993 | if (!filter_check_discard(call, entry, tr->buffer, event)) |
994 | ring_buffer_unlock_commit(tr->buffer, event); | |
f0a920d5 IM |
995 | } |
996 | ||
c0a0d0d3 FW |
997 | void ftrace_trace_stack(struct trace_array *tr, unsigned long flags, int skip, |
998 | int pc) | |
53614991 SR |
999 | { |
1000 | if (!(trace_flags & TRACE_ITER_STACKTRACE)) | |
1001 | return; | |
1002 | ||
7be42151 | 1003 | __ftrace_trace_stack(tr, flags, skip, pc); |
53614991 SR |
1004 | } |
1005 | ||
c0a0d0d3 FW |
1006 | void __trace_stack(struct trace_array *tr, unsigned long flags, int skip, |
1007 | int pc) | |
38697053 | 1008 | { |
7be42151 | 1009 | __ftrace_trace_stack(tr, flags, skip, pc); |
38697053 SR |
1010 | } |
1011 | ||
c0a0d0d3 | 1012 | void ftrace_trace_userstack(struct trace_array *tr, unsigned long flags, int pc) |
02b67518 | 1013 | { |
e1112b4d | 1014 | struct ftrace_event_call *call = &event_user_stack; |
8d7c6a96 | 1015 | struct ring_buffer_event *event; |
02b67518 TE |
1016 | struct userstack_entry *entry; |
1017 | struct stack_trace trace; | |
02b67518 TE |
1018 | |
1019 | if (!(trace_flags & TRACE_ITER_USERSTACKTRACE)) | |
1020 | return; | |
1021 | ||
51a763dd ACM |
1022 | event = trace_buffer_lock_reserve(tr, TRACE_USER_STACK, |
1023 | sizeof(*entry), flags, pc); | |
02b67518 TE |
1024 | if (!event) |
1025 | return; | |
1026 | entry = ring_buffer_event_data(event); | |
02b67518 TE |
1027 | |
1028 | memset(&entry->caller, 0, sizeof(entry->caller)); | |
1029 | ||
1030 | trace.nr_entries = 0; | |
1031 | trace.max_entries = FTRACE_STACK_ENTRIES; | |
1032 | trace.skip = 0; | |
1033 | trace.entries = entry->caller; | |
1034 | ||
1035 | save_stack_trace_user(&trace); | |
eb02ce01 TZ |
1036 | if (!filter_check_discard(call, entry, tr->buffer, event)) |
1037 | ring_buffer_unlock_commit(tr->buffer, event); | |
02b67518 TE |
1038 | } |
1039 | ||
4fd27358 HE |
1040 | #ifdef UNUSED |
1041 | static void __trace_userstack(struct trace_array *tr, unsigned long flags) | |
02b67518 | 1042 | { |
7be42151 | 1043 | ftrace_trace_userstack(tr, flags, preempt_count()); |
02b67518 | 1044 | } |
4fd27358 | 1045 | #endif /* UNUSED */ |
02b67518 | 1046 | |
c0a0d0d3 FW |
1047 | #endif /* CONFIG_STACKTRACE */ |
1048 | ||
38697053 | 1049 | static void |
7be42151 | 1050 | ftrace_trace_special(void *__tr, |
38697053 SR |
1051 | unsigned long arg1, unsigned long arg2, unsigned long arg3, |
1052 | int pc) | |
a4feb834 | 1053 | { |
3928a8a2 | 1054 | struct ring_buffer_event *event; |
a4feb834 | 1055 | struct trace_array *tr = __tr; |
777e208d | 1056 | struct special_entry *entry; |
a4feb834 | 1057 | |
51a763dd ACM |
1058 | event = trace_buffer_lock_reserve(tr, TRACE_SPECIAL, |
1059 | sizeof(*entry), 0, pc); | |
3928a8a2 SR |
1060 | if (!event) |
1061 | return; | |
1062 | entry = ring_buffer_event_data(event); | |
777e208d SR |
1063 | entry->arg1 = arg1; |
1064 | entry->arg2 = arg2; | |
1065 | entry->arg3 = arg3; | |
51a763dd | 1066 | trace_buffer_unlock_commit(tr, event, 0, pc); |
a4feb834 IM |
1067 | } |
1068 | ||
38697053 SR |
1069 | void |
1070 | __trace_special(void *__tr, void *__data, | |
1071 | unsigned long arg1, unsigned long arg2, unsigned long arg3) | |
1072 | { | |
7be42151 | 1073 | ftrace_trace_special(__tr, arg1, arg2, arg3, preempt_count()); |
38697053 SR |
1074 | } |
1075 | ||
4902f884 SR |
1076 | void |
1077 | ftrace_special(unsigned long arg1, unsigned long arg2, unsigned long arg3) | |
1078 | { | |
1079 | struct trace_array *tr = &global_trace; | |
1080 | struct trace_array_cpu *data; | |
5aa1ba6a | 1081 | unsigned long flags; |
4902f884 | 1082 | int cpu; |
38697053 | 1083 | int pc; |
4902f884 | 1084 | |
c76f0694 | 1085 | if (tracing_disabled) |
4902f884 SR |
1086 | return; |
1087 | ||
38697053 | 1088 | pc = preempt_count(); |
5aa1ba6a | 1089 | local_irq_save(flags); |
4902f884 SR |
1090 | cpu = raw_smp_processor_id(); |
1091 | data = tr->data[cpu]; | |
4902f884 | 1092 | |
5aa1ba6a | 1093 | if (likely(atomic_inc_return(&data->disabled) == 1)) |
7be42151 | 1094 | ftrace_trace_special(tr, arg1, arg2, arg3, pc); |
4902f884 | 1095 | |
5aa1ba6a SR |
1096 | atomic_dec(&data->disabled); |
1097 | local_irq_restore(flags); | |
4902f884 SR |
1098 | } |
1099 | ||
769b0441 | 1100 | /** |
48ead020 | 1101 | * trace_vbprintk - write binary msg to tracing buffer |
769b0441 FW |
1102 | * |
1103 | */ | |
40ce74f1 | 1104 | int trace_vbprintk(unsigned long ip, const char *fmt, va_list args) |
769b0441 | 1105 | { |
80370cb7 SR |
1106 | static raw_spinlock_t trace_buf_lock = |
1107 | (raw_spinlock_t)__RAW_SPIN_LOCK_UNLOCKED; | |
769b0441 FW |
1108 | static u32 trace_buf[TRACE_BUF_SIZE]; |
1109 | ||
e1112b4d | 1110 | struct ftrace_event_call *call = &event_bprint; |
769b0441 FW |
1111 | struct ring_buffer_event *event; |
1112 | struct trace_array *tr = &global_trace; | |
1113 | struct trace_array_cpu *data; | |
48ead020 | 1114 | struct bprint_entry *entry; |
769b0441 | 1115 | unsigned long flags; |
3189cdb3 | 1116 | int disable; |
769b0441 FW |
1117 | int resched; |
1118 | int cpu, len = 0, size, pc; | |
1119 | ||
1120 | if (unlikely(tracing_selftest_running || tracing_disabled)) | |
1121 | return 0; | |
1122 | ||
1123 | /* Don't pollute graph traces with trace_vprintk internals */ | |
1124 | pause_graph_tracing(); | |
1125 | ||
1126 | pc = preempt_count(); | |
1127 | resched = ftrace_preempt_disable(); | |
1128 | cpu = raw_smp_processor_id(); | |
1129 | data = tr->data[cpu]; | |
1130 | ||
3189cdb3 SR |
1131 | disable = atomic_inc_return(&data->disabled); |
1132 | if (unlikely(disable != 1)) | |
769b0441 FW |
1133 | goto out; |
1134 | ||
80370cb7 SR |
1135 | /* Lockdep uses trace_printk for lock tracing */ |
1136 | local_irq_save(flags); | |
1137 | __raw_spin_lock(&trace_buf_lock); | |
769b0441 FW |
1138 | len = vbin_printf(trace_buf, TRACE_BUF_SIZE, fmt, args); |
1139 | ||
1140 | if (len > TRACE_BUF_SIZE || len < 0) | |
1141 | goto out_unlock; | |
1142 | ||
1143 | size = sizeof(*entry) + sizeof(u32) * len; | |
48ead020 | 1144 | event = trace_buffer_lock_reserve(tr, TRACE_BPRINT, size, flags, pc); |
769b0441 FW |
1145 | if (!event) |
1146 | goto out_unlock; | |
1147 | entry = ring_buffer_event_data(event); | |
1148 | entry->ip = ip; | |
769b0441 FW |
1149 | entry->fmt = fmt; |
1150 | ||
1151 | memcpy(entry->buf, trace_buf, sizeof(u32) * len); | |
eb02ce01 TZ |
1152 | if (!filter_check_discard(call, entry, tr->buffer, event)) |
1153 | ring_buffer_unlock_commit(tr->buffer, event); | |
769b0441 FW |
1154 | |
1155 | out_unlock: | |
80370cb7 SR |
1156 | __raw_spin_unlock(&trace_buf_lock); |
1157 | local_irq_restore(flags); | |
769b0441 FW |
1158 | |
1159 | out: | |
3189cdb3 | 1160 | atomic_dec_return(&data->disabled); |
769b0441 FW |
1161 | ftrace_preempt_enable(resched); |
1162 | unpause_graph_tracing(); | |
1163 | ||
1164 | return len; | |
1165 | } | |
48ead020 FW |
1166 | EXPORT_SYMBOL_GPL(trace_vbprintk); |
1167 | ||
40ce74f1 | 1168 | int trace_vprintk(unsigned long ip, const char *fmt, va_list args) |
48ead020 FW |
1169 | { |
1170 | static raw_spinlock_t trace_buf_lock = __RAW_SPIN_LOCK_UNLOCKED; | |
1171 | static char trace_buf[TRACE_BUF_SIZE]; | |
1172 | ||
e1112b4d | 1173 | struct ftrace_event_call *call = &event_print; |
48ead020 FW |
1174 | struct ring_buffer_event *event; |
1175 | struct trace_array *tr = &global_trace; | |
1176 | struct trace_array_cpu *data; | |
1177 | int cpu, len = 0, size, pc; | |
1178 | struct print_entry *entry; | |
1179 | unsigned long irq_flags; | |
3189cdb3 | 1180 | int disable; |
48ead020 FW |
1181 | |
1182 | if (tracing_disabled || tracing_selftest_running) | |
1183 | return 0; | |
1184 | ||
1185 | pc = preempt_count(); | |
1186 | preempt_disable_notrace(); | |
1187 | cpu = raw_smp_processor_id(); | |
1188 | data = tr->data[cpu]; | |
1189 | ||
3189cdb3 SR |
1190 | disable = atomic_inc_return(&data->disabled); |
1191 | if (unlikely(disable != 1)) | |
48ead020 FW |
1192 | goto out; |
1193 | ||
1194 | pause_graph_tracing(); | |
1195 | raw_local_irq_save(irq_flags); | |
1196 | __raw_spin_lock(&trace_buf_lock); | |
1197 | len = vsnprintf(trace_buf, TRACE_BUF_SIZE, fmt, args); | |
1198 | ||
1199 | len = min(len, TRACE_BUF_SIZE-1); | |
1200 | trace_buf[len] = 0; | |
1201 | ||
1202 | size = sizeof(*entry) + len + 1; | |
1203 | event = trace_buffer_lock_reserve(tr, TRACE_PRINT, size, irq_flags, pc); | |
1204 | if (!event) | |
1205 | goto out_unlock; | |
1206 | entry = ring_buffer_event_data(event); | |
1207 | entry->ip = ip; | |
48ead020 FW |
1208 | |
1209 | memcpy(&entry->buf, trace_buf, len); | |
1210 | entry->buf[len] = 0; | |
eb02ce01 TZ |
1211 | if (!filter_check_discard(call, entry, tr->buffer, event)) |
1212 | ring_buffer_unlock_commit(tr->buffer, event); | |
48ead020 FW |
1213 | |
1214 | out_unlock: | |
1215 | __raw_spin_unlock(&trace_buf_lock); | |
1216 | raw_local_irq_restore(irq_flags); | |
1217 | unpause_graph_tracing(); | |
1218 | out: | |
3189cdb3 | 1219 | atomic_dec_return(&data->disabled); |
48ead020 FW |
1220 | preempt_enable_notrace(); |
1221 | ||
1222 | return len; | |
1223 | } | |
769b0441 FW |
1224 | EXPORT_SYMBOL_GPL(trace_vprintk); |
1225 | ||
bc0c38d1 SR |
1226 | enum trace_file_type { |
1227 | TRACE_FILE_LAT_FMT = 1, | |
12ef7d44 | 1228 | TRACE_FILE_ANNOTATE = 2, |
bc0c38d1 SR |
1229 | }; |
1230 | ||
e2ac8ef5 | 1231 | static void trace_iterator_increment(struct trace_iterator *iter) |
5a90f577 | 1232 | { |
d769041f SR |
1233 | /* Don't allow ftrace to trace into the ring buffers */ |
1234 | ftrace_disable_cpu(); | |
1235 | ||
5a90f577 | 1236 | iter->idx++; |
d769041f SR |
1237 | if (iter->buffer_iter[iter->cpu]) |
1238 | ring_buffer_read(iter->buffer_iter[iter->cpu], NULL); | |
1239 | ||
1240 | ftrace_enable_cpu(); | |
5a90f577 SR |
1241 | } |
1242 | ||
e309b41d | 1243 | static struct trace_entry * |
3928a8a2 | 1244 | peek_next_entry(struct trace_iterator *iter, int cpu, u64 *ts) |
dd0e545f | 1245 | { |
3928a8a2 SR |
1246 | struct ring_buffer_event *event; |
1247 | struct ring_buffer_iter *buf_iter = iter->buffer_iter[cpu]; | |
dd0e545f | 1248 | |
d769041f SR |
1249 | /* Don't allow ftrace to trace into the ring buffers */ |
1250 | ftrace_disable_cpu(); | |
1251 | ||
1252 | if (buf_iter) | |
1253 | event = ring_buffer_iter_peek(buf_iter, ts); | |
1254 | else | |
1255 | event = ring_buffer_peek(iter->tr->buffer, cpu, ts); | |
1256 | ||
1257 | ftrace_enable_cpu(); | |
1258 | ||
3928a8a2 | 1259 | return event ? ring_buffer_event_data(event) : NULL; |
dd0e545f | 1260 | } |
d769041f | 1261 | |
dd0e545f | 1262 | static struct trace_entry * |
3928a8a2 | 1263 | __find_next_entry(struct trace_iterator *iter, int *ent_cpu, u64 *ent_ts) |
bc0c38d1 | 1264 | { |
3928a8a2 | 1265 | struct ring_buffer *buffer = iter->tr->buffer; |
bc0c38d1 | 1266 | struct trace_entry *ent, *next = NULL; |
b04cc6b1 | 1267 | int cpu_file = iter->cpu_file; |
3928a8a2 | 1268 | u64 next_ts = 0, ts; |
bc0c38d1 SR |
1269 | int next_cpu = -1; |
1270 | int cpu; | |
1271 | ||
b04cc6b1 FW |
1272 | /* |
1273 | * If we are in a per_cpu trace file, don't bother by iterating over | |
1274 | * all cpu and peek directly. | |
1275 | */ | |
1276 | if (cpu_file > TRACE_PIPE_ALL_CPU) { | |
1277 | if (ring_buffer_empty_cpu(buffer, cpu_file)) | |
1278 | return NULL; | |
1279 | ent = peek_next_entry(iter, cpu_file, ent_ts); | |
1280 | if (ent_cpu) | |
1281 | *ent_cpu = cpu_file; | |
1282 | ||
1283 | return ent; | |
1284 | } | |
1285 | ||
ab46428c | 1286 | for_each_tracing_cpu(cpu) { |
dd0e545f | 1287 | |
3928a8a2 SR |
1288 | if (ring_buffer_empty_cpu(buffer, cpu)) |
1289 | continue; | |
dd0e545f | 1290 | |
3928a8a2 | 1291 | ent = peek_next_entry(iter, cpu, &ts); |
dd0e545f | 1292 | |
cdd31cd2 IM |
1293 | /* |
1294 | * Pick the entry with the smallest timestamp: | |
1295 | */ | |
3928a8a2 | 1296 | if (ent && (!next || ts < next_ts)) { |
bc0c38d1 SR |
1297 | next = ent; |
1298 | next_cpu = cpu; | |
3928a8a2 | 1299 | next_ts = ts; |
bc0c38d1 SR |
1300 | } |
1301 | } | |
1302 | ||
1303 | if (ent_cpu) | |
1304 | *ent_cpu = next_cpu; | |
1305 | ||
3928a8a2 SR |
1306 | if (ent_ts) |
1307 | *ent_ts = next_ts; | |
1308 | ||
bc0c38d1 SR |
1309 | return next; |
1310 | } | |
1311 | ||
dd0e545f | 1312 | /* Find the next real entry, without updating the iterator itself */ |
c4a8e8be FW |
1313 | struct trace_entry *trace_find_next_entry(struct trace_iterator *iter, |
1314 | int *ent_cpu, u64 *ent_ts) | |
bc0c38d1 | 1315 | { |
3928a8a2 | 1316 | return __find_next_entry(iter, ent_cpu, ent_ts); |
dd0e545f SR |
1317 | } |
1318 | ||
1319 | /* Find the next real entry, and increment the iterator to the next entry */ | |
1320 | static void *find_next_entry_inc(struct trace_iterator *iter) | |
1321 | { | |
3928a8a2 | 1322 | iter->ent = __find_next_entry(iter, &iter->cpu, &iter->ts); |
dd0e545f | 1323 | |
3928a8a2 | 1324 | if (iter->ent) |
e2ac8ef5 | 1325 | trace_iterator_increment(iter); |
dd0e545f | 1326 | |
3928a8a2 | 1327 | return iter->ent ? iter : NULL; |
b3806b43 | 1328 | } |
bc0c38d1 | 1329 | |
e309b41d | 1330 | static void trace_consume(struct trace_iterator *iter) |
b3806b43 | 1331 | { |
d769041f SR |
1332 | /* Don't allow ftrace to trace into the ring buffers */ |
1333 | ftrace_disable_cpu(); | |
3928a8a2 | 1334 | ring_buffer_consume(iter->tr->buffer, iter->cpu, &iter->ts); |
d769041f | 1335 | ftrace_enable_cpu(); |
bc0c38d1 SR |
1336 | } |
1337 | ||
e309b41d | 1338 | static void *s_next(struct seq_file *m, void *v, loff_t *pos) |
bc0c38d1 SR |
1339 | { |
1340 | struct trace_iterator *iter = m->private; | |
bc0c38d1 | 1341 | int i = (int)*pos; |
4e3c3333 | 1342 | void *ent; |
bc0c38d1 SR |
1343 | |
1344 | (*pos)++; | |
1345 | ||
1346 | /* can't go backwards */ | |
1347 | if (iter->idx > i) | |
1348 | return NULL; | |
1349 | ||
1350 | if (iter->idx < 0) | |
1351 | ent = find_next_entry_inc(iter); | |
1352 | else | |
1353 | ent = iter; | |
1354 | ||
1355 | while (ent && iter->idx < i) | |
1356 | ent = find_next_entry_inc(iter); | |
1357 | ||
1358 | iter->pos = *pos; | |
1359 | ||
bc0c38d1 SR |
1360 | return ent; |
1361 | } | |
1362 | ||
d7350c3f FW |
1363 | /* |
1364 | * No necessary locking here. The worst thing which can | |
1365 | * happen is loosing events consumed at the same time | |
1366 | * by a trace_pipe reader. | |
1367 | * Other than that, we don't risk to crash the ring buffer | |
1368 | * because it serializes the readers. | |
1369 | * | |
1370 | * The current tracer is copied to avoid a global locking | |
1371 | * all around. | |
1372 | */ | |
bc0c38d1 SR |
1373 | static void *s_start(struct seq_file *m, loff_t *pos) |
1374 | { | |
1375 | struct trace_iterator *iter = m->private; | |
d7350c3f | 1376 | static struct tracer *old_tracer; |
b04cc6b1 | 1377 | int cpu_file = iter->cpu_file; |
bc0c38d1 SR |
1378 | void *p = NULL; |
1379 | loff_t l = 0; | |
3928a8a2 | 1380 | int cpu; |
bc0c38d1 | 1381 | |
d7350c3f | 1382 | /* copy the tracer to avoid using a global lock all around */ |
bc0c38d1 | 1383 | mutex_lock(&trace_types_lock); |
d7350c3f FW |
1384 | if (unlikely(old_tracer != current_trace && current_trace)) { |
1385 | old_tracer = current_trace; | |
1386 | *iter->trace = *current_trace; | |
d15f57f2 | 1387 | } |
d7350c3f | 1388 | mutex_unlock(&trace_types_lock); |
bc0c38d1 SR |
1389 | |
1390 | atomic_inc(&trace_record_cmdline_disabled); | |
1391 | ||
bc0c38d1 SR |
1392 | if (*pos != iter->pos) { |
1393 | iter->ent = NULL; | |
1394 | iter->cpu = 0; | |
1395 | iter->idx = -1; | |
1396 | ||
d769041f SR |
1397 | ftrace_disable_cpu(); |
1398 | ||
b04cc6b1 FW |
1399 | if (cpu_file == TRACE_PIPE_ALL_CPU) { |
1400 | for_each_tracing_cpu(cpu) | |
1401 | ring_buffer_iter_reset(iter->buffer_iter[cpu]); | |
1402 | } else | |
1403 | ring_buffer_iter_reset(iter->buffer_iter[cpu_file]); | |
1404 | ||
bc0c38d1 | 1405 | |
d769041f SR |
1406 | ftrace_enable_cpu(); |
1407 | ||
bc0c38d1 SR |
1408 | for (p = iter; p && l < *pos; p = s_next(m, p, &l)) |
1409 | ; | |
1410 | ||
1411 | } else { | |
4c11d7ae | 1412 | l = *pos - 1; |
bc0c38d1 SR |
1413 | p = s_next(m, p, &l); |
1414 | } | |
1415 | ||
4f535968 | 1416 | trace_event_read_lock(); |
bc0c38d1 SR |
1417 | return p; |
1418 | } | |
1419 | ||
1420 | static void s_stop(struct seq_file *m, void *p) | |
1421 | { | |
bc0c38d1 | 1422 | atomic_dec(&trace_record_cmdline_disabled); |
4f535968 | 1423 | trace_event_read_unlock(); |
bc0c38d1 SR |
1424 | } |
1425 | ||
e309b41d | 1426 | static void print_lat_help_header(struct seq_file *m) |
bc0c38d1 | 1427 | { |
a6168353 ME |
1428 | seq_puts(m, "# _------=> CPU# \n"); |
1429 | seq_puts(m, "# / _-----=> irqs-off \n"); | |
1430 | seq_puts(m, "# | / _----=> need-resched \n"); | |
1431 | seq_puts(m, "# || / _---=> hardirq/softirq \n"); | |
1432 | seq_puts(m, "# ||| / _--=> preempt-depth \n"); | |
1433 | seq_puts(m, "# |||| / \n"); | |
1434 | seq_puts(m, "# ||||| delay \n"); | |
1435 | seq_puts(m, "# cmd pid ||||| time | caller \n"); | |
1436 | seq_puts(m, "# \\ / ||||| \\ | / \n"); | |
bc0c38d1 SR |
1437 | } |
1438 | ||
e309b41d | 1439 | static void print_func_help_header(struct seq_file *m) |
bc0c38d1 | 1440 | { |
a6168353 ME |
1441 | seq_puts(m, "# TASK-PID CPU# TIMESTAMP FUNCTION\n"); |
1442 | seq_puts(m, "# | | | | |\n"); | |
bc0c38d1 SR |
1443 | } |
1444 | ||
1445 | ||
e309b41d | 1446 | static void |
bc0c38d1 SR |
1447 | print_trace_header(struct seq_file *m, struct trace_iterator *iter) |
1448 | { | |
1449 | unsigned long sym_flags = (trace_flags & TRACE_ITER_SYM_MASK); | |
1450 | struct trace_array *tr = iter->tr; | |
1451 | struct trace_array_cpu *data = tr->data[tr->cpu]; | |
1452 | struct tracer *type = current_trace; | |
3928a8a2 SR |
1453 | unsigned long total; |
1454 | unsigned long entries; | |
bc0c38d1 SR |
1455 | const char *name = "preemption"; |
1456 | ||
1457 | if (type) | |
1458 | name = type->name; | |
1459 | ||
3928a8a2 SR |
1460 | entries = ring_buffer_entries(iter->tr->buffer); |
1461 | total = entries + | |
1462 | ring_buffer_overruns(iter->tr->buffer); | |
bc0c38d1 | 1463 | |
888b55dc | 1464 | seq_printf(m, "# %s latency trace v1.1.5 on %s\n", |
bc0c38d1 | 1465 | name, UTS_RELEASE); |
888b55dc | 1466 | seq_puts(m, "# -----------------------------------" |
bc0c38d1 | 1467 | "---------------------------------\n"); |
888b55dc | 1468 | seq_printf(m, "# latency: %lu us, #%lu/%lu, CPU#%d |" |
bc0c38d1 | 1469 | " (M:%s VP:%d, KP:%d, SP:%d HP:%d", |
57f50be1 | 1470 | nsecs_to_usecs(data->saved_latency), |
bc0c38d1 | 1471 | entries, |
4c11d7ae | 1472 | total, |
bc0c38d1 SR |
1473 | tr->cpu, |
1474 | #if defined(CONFIG_PREEMPT_NONE) | |
1475 | "server", | |
1476 | #elif defined(CONFIG_PREEMPT_VOLUNTARY) | |
1477 | "desktop", | |
b5c21b45 | 1478 | #elif defined(CONFIG_PREEMPT) |
bc0c38d1 SR |
1479 | "preempt", |
1480 | #else | |
1481 | "unknown", | |
1482 | #endif | |
1483 | /* These are reserved for later use */ | |
1484 | 0, 0, 0, 0); | |
1485 | #ifdef CONFIG_SMP | |
1486 | seq_printf(m, " #P:%d)\n", num_online_cpus()); | |
1487 | #else | |
1488 | seq_puts(m, ")\n"); | |
1489 | #endif | |
888b55dc KM |
1490 | seq_puts(m, "# -----------------\n"); |
1491 | seq_printf(m, "# | task: %.16s-%d " | |
bc0c38d1 SR |
1492 | "(uid:%d nice:%ld policy:%ld rt_prio:%ld)\n", |
1493 | data->comm, data->pid, data->uid, data->nice, | |
1494 | data->policy, data->rt_priority); | |
888b55dc | 1495 | seq_puts(m, "# -----------------\n"); |
bc0c38d1 SR |
1496 | |
1497 | if (data->critical_start) { | |
888b55dc | 1498 | seq_puts(m, "# => started at: "); |
214023c3 SR |
1499 | seq_print_ip_sym(&iter->seq, data->critical_start, sym_flags); |
1500 | trace_print_seq(m, &iter->seq); | |
888b55dc | 1501 | seq_puts(m, "\n# => ended at: "); |
214023c3 SR |
1502 | seq_print_ip_sym(&iter->seq, data->critical_end, sym_flags); |
1503 | trace_print_seq(m, &iter->seq); | |
888b55dc | 1504 | seq_puts(m, "#\n"); |
bc0c38d1 SR |
1505 | } |
1506 | ||
888b55dc | 1507 | seq_puts(m, "#\n"); |
bc0c38d1 SR |
1508 | } |
1509 | ||
a309720c SR |
1510 | static void test_cpu_buff_start(struct trace_iterator *iter) |
1511 | { | |
1512 | struct trace_seq *s = &iter->seq; | |
1513 | ||
12ef7d44 SR |
1514 | if (!(trace_flags & TRACE_ITER_ANNOTATE)) |
1515 | return; | |
1516 | ||
1517 | if (!(iter->iter_flags & TRACE_FILE_ANNOTATE)) | |
1518 | return; | |
1519 | ||
4462344e | 1520 | if (cpumask_test_cpu(iter->cpu, iter->started)) |
a309720c SR |
1521 | return; |
1522 | ||
4462344e | 1523 | cpumask_set_cpu(iter->cpu, iter->started); |
b0dfa978 FW |
1524 | |
1525 | /* Don't print started cpu buffer for the first entry of the trace */ | |
1526 | if (iter->idx > 1) | |
1527 | trace_seq_printf(s, "##### CPU %u buffer started ####\n", | |
1528 | iter->cpu); | |
a309720c SR |
1529 | } |
1530 | ||
2c4f035f | 1531 | static enum print_line_t print_trace_fmt(struct trace_iterator *iter) |
bc0c38d1 | 1532 | { |
214023c3 | 1533 | struct trace_seq *s = &iter->seq; |
bc0c38d1 | 1534 | unsigned long sym_flags = (trace_flags & TRACE_ITER_SYM_MASK); |
4e3c3333 | 1535 | struct trace_entry *entry; |
f633cef0 | 1536 | struct trace_event *event; |
bc0c38d1 | 1537 | |
4e3c3333 | 1538 | entry = iter->ent; |
dd0e545f | 1539 | |
a309720c SR |
1540 | test_cpu_buff_start(iter); |
1541 | ||
c4a8e8be | 1542 | event = ftrace_find_event(entry->type); |
bc0c38d1 | 1543 | |
c4a8e8be | 1544 | if (trace_flags & TRACE_ITER_CONTEXT_INFO) { |
27d48be8 SR |
1545 | if (iter->iter_flags & TRACE_FILE_LAT_FMT) { |
1546 | if (!trace_print_lat_context(iter)) | |
1547 | goto partial; | |
1548 | } else { | |
1549 | if (!trace_print_context(iter)) | |
1550 | goto partial; | |
1551 | } | |
c4a8e8be | 1552 | } |
bc0c38d1 | 1553 | |
268ccda0 | 1554 | if (event) |
d9793bd8 ACM |
1555 | return event->trace(iter, sym_flags); |
1556 | ||
1557 | if (!trace_seq_printf(s, "Unknown type %d\n", entry->type)) | |
1558 | goto partial; | |
02b67518 | 1559 | |
2c4f035f | 1560 | return TRACE_TYPE_HANDLED; |
d9793bd8 ACM |
1561 | partial: |
1562 | return TRACE_TYPE_PARTIAL_LINE; | |
bc0c38d1 SR |
1563 | } |
1564 | ||
2c4f035f | 1565 | static enum print_line_t print_raw_fmt(struct trace_iterator *iter) |
f9896bf3 IM |
1566 | { |
1567 | struct trace_seq *s = &iter->seq; | |
1568 | struct trace_entry *entry; | |
f633cef0 | 1569 | struct trace_event *event; |
f9896bf3 IM |
1570 | |
1571 | entry = iter->ent; | |
dd0e545f | 1572 | |
c4a8e8be | 1573 | if (trace_flags & TRACE_ITER_CONTEXT_INFO) { |
d9793bd8 ACM |
1574 | if (!trace_seq_printf(s, "%d %d %llu ", |
1575 | entry->pid, iter->cpu, iter->ts)) | |
1576 | goto partial; | |
c4a8e8be | 1577 | } |
f9896bf3 | 1578 | |
f633cef0 | 1579 | event = ftrace_find_event(entry->type); |
268ccda0 | 1580 | if (event) |
d9793bd8 ACM |
1581 | return event->raw(iter, 0); |
1582 | ||
1583 | if (!trace_seq_printf(s, "%d ?\n", entry->type)) | |
1584 | goto partial; | |
777e208d | 1585 | |
2c4f035f | 1586 | return TRACE_TYPE_HANDLED; |
d9793bd8 ACM |
1587 | partial: |
1588 | return TRACE_TYPE_PARTIAL_LINE; | |
f9896bf3 IM |
1589 | } |
1590 | ||
2c4f035f | 1591 | static enum print_line_t print_hex_fmt(struct trace_iterator *iter) |
5e3ca0ec IM |
1592 | { |
1593 | struct trace_seq *s = &iter->seq; | |
1594 | unsigned char newline = '\n'; | |
1595 | struct trace_entry *entry; | |
f633cef0 | 1596 | struct trace_event *event; |
5e3ca0ec IM |
1597 | |
1598 | entry = iter->ent; | |
dd0e545f | 1599 | |
c4a8e8be FW |
1600 | if (trace_flags & TRACE_ITER_CONTEXT_INFO) { |
1601 | SEQ_PUT_HEX_FIELD_RET(s, entry->pid); | |
1602 | SEQ_PUT_HEX_FIELD_RET(s, iter->cpu); | |
1603 | SEQ_PUT_HEX_FIELD_RET(s, iter->ts); | |
1604 | } | |
5e3ca0ec | 1605 | |
f633cef0 | 1606 | event = ftrace_find_event(entry->type); |
268ccda0 | 1607 | if (event) { |
ae7462b4 | 1608 | enum print_line_t ret = event->hex(iter, 0); |
d9793bd8 ACM |
1609 | if (ret != TRACE_TYPE_HANDLED) |
1610 | return ret; | |
1611 | } | |
7104f300 | 1612 | |
5e3ca0ec IM |
1613 | SEQ_PUT_FIELD_RET(s, newline); |
1614 | ||
2c4f035f | 1615 | return TRACE_TYPE_HANDLED; |
5e3ca0ec IM |
1616 | } |
1617 | ||
2c4f035f | 1618 | static enum print_line_t print_bin_fmt(struct trace_iterator *iter) |
cb0f12aa IM |
1619 | { |
1620 | struct trace_seq *s = &iter->seq; | |
1621 | struct trace_entry *entry; | |
f633cef0 | 1622 | struct trace_event *event; |
cb0f12aa IM |
1623 | |
1624 | entry = iter->ent; | |
dd0e545f | 1625 | |
c4a8e8be FW |
1626 | if (trace_flags & TRACE_ITER_CONTEXT_INFO) { |
1627 | SEQ_PUT_FIELD_RET(s, entry->pid); | |
1830b52d | 1628 | SEQ_PUT_FIELD_RET(s, iter->cpu); |
c4a8e8be FW |
1629 | SEQ_PUT_FIELD_RET(s, iter->ts); |
1630 | } | |
cb0f12aa | 1631 | |
f633cef0 | 1632 | event = ftrace_find_event(entry->type); |
268ccda0 | 1633 | return event ? event->binary(iter, 0) : TRACE_TYPE_HANDLED; |
cb0f12aa IM |
1634 | } |
1635 | ||
bc0c38d1 SR |
1636 | static int trace_empty(struct trace_iterator *iter) |
1637 | { | |
bc0c38d1 SR |
1638 | int cpu; |
1639 | ||
9aba60fe SR |
1640 | /* If we are looking at one CPU buffer, only check that one */ |
1641 | if (iter->cpu_file != TRACE_PIPE_ALL_CPU) { | |
1642 | cpu = iter->cpu_file; | |
1643 | if (iter->buffer_iter[cpu]) { | |
1644 | if (!ring_buffer_iter_empty(iter->buffer_iter[cpu])) | |
1645 | return 0; | |
1646 | } else { | |
1647 | if (!ring_buffer_empty_cpu(iter->tr->buffer, cpu)) | |
1648 | return 0; | |
1649 | } | |
1650 | return 1; | |
1651 | } | |
1652 | ||
ab46428c | 1653 | for_each_tracing_cpu(cpu) { |
d769041f SR |
1654 | if (iter->buffer_iter[cpu]) { |
1655 | if (!ring_buffer_iter_empty(iter->buffer_iter[cpu])) | |
1656 | return 0; | |
1657 | } else { | |
1658 | if (!ring_buffer_empty_cpu(iter->tr->buffer, cpu)) | |
1659 | return 0; | |
1660 | } | |
bc0c38d1 | 1661 | } |
d769041f | 1662 | |
797d3712 | 1663 | return 1; |
bc0c38d1 SR |
1664 | } |
1665 | ||
4f535968 | 1666 | /* Called with trace_event_read_lock() held. */ |
2c4f035f | 1667 | static enum print_line_t print_trace_line(struct trace_iterator *iter) |
f9896bf3 | 1668 | { |
2c4f035f FW |
1669 | enum print_line_t ret; |
1670 | ||
1671 | if (iter->trace && iter->trace->print_line) { | |
1672 | ret = iter->trace->print_line(iter); | |
1673 | if (ret != TRACE_TYPE_UNHANDLED) | |
1674 | return ret; | |
1675 | } | |
72829bc3 | 1676 | |
48ead020 FW |
1677 | if (iter->ent->type == TRACE_BPRINT && |
1678 | trace_flags & TRACE_ITER_PRINTK && | |
1679 | trace_flags & TRACE_ITER_PRINTK_MSGONLY) | |
5ef841f6 | 1680 | return trace_print_bprintk_msg_only(iter); |
48ead020 | 1681 | |
66896a85 FW |
1682 | if (iter->ent->type == TRACE_PRINT && |
1683 | trace_flags & TRACE_ITER_PRINTK && | |
1684 | trace_flags & TRACE_ITER_PRINTK_MSGONLY) | |
5ef841f6 | 1685 | return trace_print_printk_msg_only(iter); |
66896a85 | 1686 | |
cb0f12aa IM |
1687 | if (trace_flags & TRACE_ITER_BIN) |
1688 | return print_bin_fmt(iter); | |
1689 | ||
5e3ca0ec IM |
1690 | if (trace_flags & TRACE_ITER_HEX) |
1691 | return print_hex_fmt(iter); | |
1692 | ||
f9896bf3 IM |
1693 | if (trace_flags & TRACE_ITER_RAW) |
1694 | return print_raw_fmt(iter); | |
1695 | ||
f9896bf3 IM |
1696 | return print_trace_fmt(iter); |
1697 | } | |
1698 | ||
bc0c38d1 SR |
1699 | static int s_show(struct seq_file *m, void *v) |
1700 | { | |
1701 | struct trace_iterator *iter = v; | |
1702 | ||
1703 | if (iter->ent == NULL) { | |
1704 | if (iter->tr) { | |
1705 | seq_printf(m, "# tracer: %s\n", iter->trace->name); | |
1706 | seq_puts(m, "#\n"); | |
1707 | } | |
8bba1bf5 MM |
1708 | if (iter->trace && iter->trace->print_header) |
1709 | iter->trace->print_header(m); | |
1710 | else if (iter->iter_flags & TRACE_FILE_LAT_FMT) { | |
bc0c38d1 SR |
1711 | /* print nothing if the buffers are empty */ |
1712 | if (trace_empty(iter)) | |
1713 | return 0; | |
1714 | print_trace_header(m, iter); | |
1715 | if (!(trace_flags & TRACE_ITER_VERBOSE)) | |
1716 | print_lat_help_header(m); | |
1717 | } else { | |
1718 | if (!(trace_flags & TRACE_ITER_VERBOSE)) | |
1719 | print_func_help_header(m); | |
1720 | } | |
1721 | } else { | |
f9896bf3 | 1722 | print_trace_line(iter); |
214023c3 | 1723 | trace_print_seq(m, &iter->seq); |
bc0c38d1 SR |
1724 | } |
1725 | ||
1726 | return 0; | |
1727 | } | |
1728 | ||
1729 | static struct seq_operations tracer_seq_ops = { | |
4bf39a94 IM |
1730 | .start = s_start, |
1731 | .next = s_next, | |
1732 | .stop = s_stop, | |
1733 | .show = s_show, | |
bc0c38d1 SR |
1734 | }; |
1735 | ||
e309b41d | 1736 | static struct trace_iterator * |
85a2f9b4 | 1737 | __tracing_open(struct inode *inode, struct file *file) |
bc0c38d1 | 1738 | { |
b04cc6b1 | 1739 | long cpu_file = (long) inode->i_private; |
85a2f9b4 | 1740 | void *fail_ret = ERR_PTR(-ENOMEM); |
bc0c38d1 | 1741 | struct trace_iterator *iter; |
3928a8a2 | 1742 | struct seq_file *m; |
85a2f9b4 | 1743 | int cpu, ret; |
bc0c38d1 | 1744 | |
85a2f9b4 SR |
1745 | if (tracing_disabled) |
1746 | return ERR_PTR(-ENODEV); | |
60a11774 | 1747 | |
bc0c38d1 | 1748 | iter = kzalloc(sizeof(*iter), GFP_KERNEL); |
85a2f9b4 SR |
1749 | if (!iter) |
1750 | return ERR_PTR(-ENOMEM); | |
bc0c38d1 | 1751 | |
d7350c3f FW |
1752 | /* |
1753 | * We make a copy of the current tracer to avoid concurrent | |
1754 | * changes on it while we are reading. | |
1755 | */ | |
bc0c38d1 | 1756 | mutex_lock(&trace_types_lock); |
d7350c3f | 1757 | iter->trace = kzalloc(sizeof(*iter->trace), GFP_KERNEL); |
85a2f9b4 | 1758 | if (!iter->trace) |
d7350c3f | 1759 | goto fail; |
85a2f9b4 | 1760 | |
d7350c3f FW |
1761 | if (current_trace) |
1762 | *iter->trace = *current_trace; | |
1763 | ||
b0dfa978 FW |
1764 | if (!alloc_cpumask_var(&iter->started, GFP_KERNEL)) |
1765 | goto fail; | |
1766 | ||
1767 | cpumask_clear(iter->started); | |
1768 | ||
bc0c38d1 SR |
1769 | if (current_trace && current_trace->print_max) |
1770 | iter->tr = &max_tr; | |
1771 | else | |
b04cc6b1 | 1772 | iter->tr = &global_trace; |
bc0c38d1 | 1773 | iter->pos = -1; |
d7350c3f | 1774 | mutex_init(&iter->mutex); |
b04cc6b1 | 1775 | iter->cpu_file = cpu_file; |
bc0c38d1 | 1776 | |
8bba1bf5 MM |
1777 | /* Notify the tracer early; before we stop tracing. */ |
1778 | if (iter->trace && iter->trace->open) | |
a93751ca | 1779 | iter->trace->open(iter); |
8bba1bf5 | 1780 | |
12ef7d44 SR |
1781 | /* Annotate start of buffers if we had overruns */ |
1782 | if (ring_buffer_overruns(iter->tr->buffer)) | |
1783 | iter->iter_flags |= TRACE_FILE_ANNOTATE; | |
1784 | ||
b04cc6b1 FW |
1785 | if (iter->cpu_file == TRACE_PIPE_ALL_CPU) { |
1786 | for_each_tracing_cpu(cpu) { | |
12ef7d44 | 1787 | |
b04cc6b1 FW |
1788 | iter->buffer_iter[cpu] = |
1789 | ring_buffer_read_start(iter->tr->buffer, cpu); | |
b04cc6b1 FW |
1790 | } |
1791 | } else { | |
1792 | cpu = iter->cpu_file; | |
3928a8a2 | 1793 | iter->buffer_iter[cpu] = |
b04cc6b1 | 1794 | ring_buffer_read_start(iter->tr->buffer, cpu); |
3928a8a2 SR |
1795 | } |
1796 | ||
bc0c38d1 | 1797 | /* TODO stop tracer */ |
85a2f9b4 SR |
1798 | ret = seq_open(file, &tracer_seq_ops); |
1799 | if (ret < 0) { | |
1800 | fail_ret = ERR_PTR(ret); | |
3928a8a2 | 1801 | goto fail_buffer; |
85a2f9b4 | 1802 | } |
bc0c38d1 | 1803 | |
3928a8a2 SR |
1804 | m = file->private_data; |
1805 | m->private = iter; | |
bc0c38d1 | 1806 | |
3928a8a2 | 1807 | /* stop the trace while dumping */ |
9036990d | 1808 | tracing_stop(); |
3928a8a2 | 1809 | |
bc0c38d1 SR |
1810 | mutex_unlock(&trace_types_lock); |
1811 | ||
bc0c38d1 | 1812 | return iter; |
3928a8a2 SR |
1813 | |
1814 | fail_buffer: | |
1815 | for_each_tracing_cpu(cpu) { | |
1816 | if (iter->buffer_iter[cpu]) | |
1817 | ring_buffer_read_finish(iter->buffer_iter[cpu]); | |
1818 | } | |
b0dfa978 | 1819 | free_cpumask_var(iter->started); |
d7350c3f | 1820 | fail: |
3928a8a2 | 1821 | mutex_unlock(&trace_types_lock); |
d7350c3f | 1822 | kfree(iter->trace); |
0bb943c7 | 1823 | kfree(iter); |
3928a8a2 | 1824 | |
85a2f9b4 | 1825 | return fail_ret; |
bc0c38d1 SR |
1826 | } |
1827 | ||
1828 | int tracing_open_generic(struct inode *inode, struct file *filp) | |
1829 | { | |
60a11774 SR |
1830 | if (tracing_disabled) |
1831 | return -ENODEV; | |
1832 | ||
bc0c38d1 SR |
1833 | filp->private_data = inode->i_private; |
1834 | return 0; | |
1835 | } | |
1836 | ||
4fd27358 | 1837 | static int tracing_release(struct inode *inode, struct file *file) |
bc0c38d1 SR |
1838 | { |
1839 | struct seq_file *m = (struct seq_file *)file->private_data; | |
4acd4d00 | 1840 | struct trace_iterator *iter; |
3928a8a2 | 1841 | int cpu; |
bc0c38d1 | 1842 | |
4acd4d00 SR |
1843 | if (!(file->f_mode & FMODE_READ)) |
1844 | return 0; | |
1845 | ||
1846 | iter = m->private; | |
1847 | ||
bc0c38d1 | 1848 | mutex_lock(&trace_types_lock); |
3928a8a2 SR |
1849 | for_each_tracing_cpu(cpu) { |
1850 | if (iter->buffer_iter[cpu]) | |
1851 | ring_buffer_read_finish(iter->buffer_iter[cpu]); | |
1852 | } | |
1853 | ||
bc0c38d1 SR |
1854 | if (iter->trace && iter->trace->close) |
1855 | iter->trace->close(iter); | |
1856 | ||
1857 | /* reenable tracing if it was previously enabled */ | |
9036990d | 1858 | tracing_start(); |
bc0c38d1 SR |
1859 | mutex_unlock(&trace_types_lock); |
1860 | ||
1861 | seq_release(inode, file); | |
d7350c3f | 1862 | mutex_destroy(&iter->mutex); |
b0dfa978 | 1863 | free_cpumask_var(iter->started); |
d7350c3f | 1864 | kfree(iter->trace); |
bc0c38d1 SR |
1865 | kfree(iter); |
1866 | return 0; | |
1867 | } | |
1868 | ||
1869 | static int tracing_open(struct inode *inode, struct file *file) | |
1870 | { | |
85a2f9b4 SR |
1871 | struct trace_iterator *iter; |
1872 | int ret = 0; | |
bc0c38d1 | 1873 | |
4acd4d00 SR |
1874 | /* If this file was open for write, then erase contents */ |
1875 | if ((file->f_mode & FMODE_WRITE) && | |
8650ae32 | 1876 | (file->f_flags & O_TRUNC)) { |
4acd4d00 | 1877 | long cpu = (long) inode->i_private; |
bc0c38d1 | 1878 | |
4acd4d00 SR |
1879 | if (cpu == TRACE_PIPE_ALL_CPU) |
1880 | tracing_reset_online_cpus(&global_trace); | |
1881 | else | |
1882 | tracing_reset(&global_trace, cpu); | |
1883 | } | |
bc0c38d1 | 1884 | |
4acd4d00 SR |
1885 | if (file->f_mode & FMODE_READ) { |
1886 | iter = __tracing_open(inode, file); | |
1887 | if (IS_ERR(iter)) | |
1888 | ret = PTR_ERR(iter); | |
1889 | else if (trace_flags & TRACE_ITER_LATENCY_FMT) | |
1890 | iter->iter_flags |= TRACE_FILE_LAT_FMT; | |
1891 | } | |
bc0c38d1 SR |
1892 | return ret; |
1893 | } | |
1894 | ||
e309b41d | 1895 | static void * |
bc0c38d1 SR |
1896 | t_next(struct seq_file *m, void *v, loff_t *pos) |
1897 | { | |
f129e965 | 1898 | struct tracer *t = v; |
bc0c38d1 SR |
1899 | |
1900 | (*pos)++; | |
1901 | ||
1902 | if (t) | |
1903 | t = t->next; | |
1904 | ||
bc0c38d1 SR |
1905 | return t; |
1906 | } | |
1907 | ||
1908 | static void *t_start(struct seq_file *m, loff_t *pos) | |
1909 | { | |
f129e965 | 1910 | struct tracer *t; |
bc0c38d1 SR |
1911 | loff_t l = 0; |
1912 | ||
1913 | mutex_lock(&trace_types_lock); | |
f129e965 | 1914 | for (t = trace_types; t && l < *pos; t = t_next(m, t, &l)) |
bc0c38d1 SR |
1915 | ; |
1916 | ||
1917 | return t; | |
1918 | } | |
1919 | ||
1920 | static void t_stop(struct seq_file *m, void *p) | |
1921 | { | |
1922 | mutex_unlock(&trace_types_lock); | |
1923 | } | |
1924 | ||
1925 | static int t_show(struct seq_file *m, void *v) | |
1926 | { | |
1927 | struct tracer *t = v; | |
1928 | ||
1929 | if (!t) | |
1930 | return 0; | |
1931 | ||
1932 | seq_printf(m, "%s", t->name); | |
1933 | if (t->next) | |
1934 | seq_putc(m, ' '); | |
1935 | else | |
1936 | seq_putc(m, '\n'); | |
1937 | ||
1938 | return 0; | |
1939 | } | |
1940 | ||
1941 | static struct seq_operations show_traces_seq_ops = { | |
4bf39a94 IM |
1942 | .start = t_start, |
1943 | .next = t_next, | |
1944 | .stop = t_stop, | |
1945 | .show = t_show, | |
bc0c38d1 SR |
1946 | }; |
1947 | ||
1948 | static int show_traces_open(struct inode *inode, struct file *file) | |
1949 | { | |
60a11774 SR |
1950 | if (tracing_disabled) |
1951 | return -ENODEV; | |
1952 | ||
f129e965 | 1953 | return seq_open(file, &show_traces_seq_ops); |
bc0c38d1 SR |
1954 | } |
1955 | ||
4acd4d00 SR |
1956 | static ssize_t |
1957 | tracing_write_stub(struct file *filp, const char __user *ubuf, | |
1958 | size_t count, loff_t *ppos) | |
1959 | { | |
1960 | return count; | |
1961 | } | |
1962 | ||
5e2336a0 | 1963 | static const struct file_operations tracing_fops = { |
4bf39a94 IM |
1964 | .open = tracing_open, |
1965 | .read = seq_read, | |
4acd4d00 | 1966 | .write = tracing_write_stub, |
4bf39a94 IM |
1967 | .llseek = seq_lseek, |
1968 | .release = tracing_release, | |
bc0c38d1 SR |
1969 | }; |
1970 | ||
5e2336a0 | 1971 | static const struct file_operations show_traces_fops = { |
c7078de1 IM |
1972 | .open = show_traces_open, |
1973 | .read = seq_read, | |
1974 | .release = seq_release, | |
1975 | }; | |
1976 | ||
36dfe925 IM |
1977 | /* |
1978 | * Only trace on a CPU if the bitmask is set: | |
1979 | */ | |
9e01c1b7 | 1980 | static cpumask_var_t tracing_cpumask; |
36dfe925 IM |
1981 | |
1982 | /* | |
1983 | * The tracer itself will not take this lock, but still we want | |
1984 | * to provide a consistent cpumask to user-space: | |
1985 | */ | |
1986 | static DEFINE_MUTEX(tracing_cpumask_update_lock); | |
1987 | ||
1988 | /* | |
1989 | * Temporary storage for the character representation of the | |
1990 | * CPU bitmask (and one more byte for the newline): | |
1991 | */ | |
1992 | static char mask_str[NR_CPUS + 1]; | |
1993 | ||
c7078de1 IM |
1994 | static ssize_t |
1995 | tracing_cpumask_read(struct file *filp, char __user *ubuf, | |
1996 | size_t count, loff_t *ppos) | |
1997 | { | |
36dfe925 | 1998 | int len; |
c7078de1 IM |
1999 | |
2000 | mutex_lock(&tracing_cpumask_update_lock); | |
36dfe925 | 2001 | |
9e01c1b7 | 2002 | len = cpumask_scnprintf(mask_str, count, tracing_cpumask); |
36dfe925 IM |
2003 | if (count - len < 2) { |
2004 | count = -EINVAL; | |
2005 | goto out_err; | |
2006 | } | |
2007 | len += sprintf(mask_str + len, "\n"); | |
2008 | count = simple_read_from_buffer(ubuf, count, ppos, mask_str, NR_CPUS+1); | |
2009 | ||
2010 | out_err: | |
c7078de1 IM |
2011 | mutex_unlock(&tracing_cpumask_update_lock); |
2012 | ||
2013 | return count; | |
2014 | } | |
2015 | ||
2016 | static ssize_t | |
2017 | tracing_cpumask_write(struct file *filp, const char __user *ubuf, | |
2018 | size_t count, loff_t *ppos) | |
2019 | { | |
36dfe925 | 2020 | int err, cpu; |
9e01c1b7 RR |
2021 | cpumask_var_t tracing_cpumask_new; |
2022 | ||
2023 | if (!alloc_cpumask_var(&tracing_cpumask_new, GFP_KERNEL)) | |
2024 | return -ENOMEM; | |
c7078de1 | 2025 | |
9e01c1b7 | 2026 | err = cpumask_parse_user(ubuf, count, tracing_cpumask_new); |
c7078de1 | 2027 | if (err) |
36dfe925 IM |
2028 | goto err_unlock; |
2029 | ||
215368e8 LZ |
2030 | mutex_lock(&tracing_cpumask_update_lock); |
2031 | ||
a5e25883 | 2032 | local_irq_disable(); |
92205c23 | 2033 | __raw_spin_lock(&ftrace_max_lock); |
ab46428c | 2034 | for_each_tracing_cpu(cpu) { |
36dfe925 IM |
2035 | /* |
2036 | * Increase/decrease the disabled counter if we are | |
2037 | * about to flip a bit in the cpumask: | |
2038 | */ | |
9e01c1b7 RR |
2039 | if (cpumask_test_cpu(cpu, tracing_cpumask) && |
2040 | !cpumask_test_cpu(cpu, tracing_cpumask_new)) { | |
36dfe925 IM |
2041 | atomic_inc(&global_trace.data[cpu]->disabled); |
2042 | } | |
9e01c1b7 RR |
2043 | if (!cpumask_test_cpu(cpu, tracing_cpumask) && |
2044 | cpumask_test_cpu(cpu, tracing_cpumask_new)) { | |
36dfe925 IM |
2045 | atomic_dec(&global_trace.data[cpu]->disabled); |
2046 | } | |
2047 | } | |
92205c23 | 2048 | __raw_spin_unlock(&ftrace_max_lock); |
a5e25883 | 2049 | local_irq_enable(); |
36dfe925 | 2050 | |
9e01c1b7 | 2051 | cpumask_copy(tracing_cpumask, tracing_cpumask_new); |
36dfe925 IM |
2052 | |
2053 | mutex_unlock(&tracing_cpumask_update_lock); | |
9e01c1b7 | 2054 | free_cpumask_var(tracing_cpumask_new); |
c7078de1 IM |
2055 | |
2056 | return count; | |
36dfe925 IM |
2057 | |
2058 | err_unlock: | |
215368e8 | 2059 | free_cpumask_var(tracing_cpumask_new); |
36dfe925 IM |
2060 | |
2061 | return err; | |
c7078de1 IM |
2062 | } |
2063 | ||
5e2336a0 | 2064 | static const struct file_operations tracing_cpumask_fops = { |
c7078de1 IM |
2065 | .open = tracing_open_generic, |
2066 | .read = tracing_cpumask_read, | |
2067 | .write = tracing_cpumask_write, | |
bc0c38d1 SR |
2068 | }; |
2069 | ||
2070 | static ssize_t | |
ee6bce52 | 2071 | tracing_trace_options_read(struct file *filp, char __user *ubuf, |
bc0c38d1 SR |
2072 | size_t cnt, loff_t *ppos) |
2073 | { | |
d8e83d26 SR |
2074 | struct tracer_opt *trace_opts; |
2075 | u32 tracer_flags; | |
2076 | int len = 0; | |
bc0c38d1 SR |
2077 | char *buf; |
2078 | int r = 0; | |
d8e83d26 | 2079 | int i; |
adf9f195 | 2080 | |
bc0c38d1 | 2081 | |
c3706f00 | 2082 | /* calculate max size */ |
bc0c38d1 SR |
2083 | for (i = 0; trace_options[i]; i++) { |
2084 | len += strlen(trace_options[i]); | |
5c6a3ae1 | 2085 | len += 3; /* "no" and newline */ |
bc0c38d1 SR |
2086 | } |
2087 | ||
d8e83d26 SR |
2088 | mutex_lock(&trace_types_lock); |
2089 | tracer_flags = current_trace->flags->val; | |
2090 | trace_opts = current_trace->flags->opts; | |
2091 | ||
adf9f195 FW |
2092 | /* |
2093 | * Increase the size with names of options specific | |
2094 | * of the current tracer. | |
2095 | */ | |
2096 | for (i = 0; trace_opts[i].name; i++) { | |
2097 | len += strlen(trace_opts[i].name); | |
5c6a3ae1 | 2098 | len += 3; /* "no" and newline */ |
adf9f195 FW |
2099 | } |
2100 | ||
ff4e9da2 XG |
2101 | /* +1 for \0 */ |
2102 | buf = kmalloc(len + 1, GFP_KERNEL); | |
d8e83d26 SR |
2103 | if (!buf) { |
2104 | mutex_unlock(&trace_types_lock); | |
bc0c38d1 | 2105 | return -ENOMEM; |
d8e83d26 | 2106 | } |
bc0c38d1 SR |
2107 | |
2108 | for (i = 0; trace_options[i]; i++) { | |
2109 | if (trace_flags & (1 << i)) | |
5c6a3ae1 | 2110 | r += sprintf(buf + r, "%s\n", trace_options[i]); |
bc0c38d1 | 2111 | else |
5c6a3ae1 | 2112 | r += sprintf(buf + r, "no%s\n", trace_options[i]); |
bc0c38d1 SR |
2113 | } |
2114 | ||
adf9f195 FW |
2115 | for (i = 0; trace_opts[i].name; i++) { |
2116 | if (tracer_flags & trace_opts[i].bit) | |
5c6a3ae1 | 2117 | r += sprintf(buf + r, "%s\n", |
adf9f195 FW |
2118 | trace_opts[i].name); |
2119 | else | |
5c6a3ae1 | 2120 | r += sprintf(buf + r, "no%s\n", |
adf9f195 FW |
2121 | trace_opts[i].name); |
2122 | } | |
d8e83d26 | 2123 | mutex_unlock(&trace_types_lock); |
adf9f195 | 2124 | |
ff4e9da2 | 2125 | WARN_ON(r >= len + 1); |
bc0c38d1 | 2126 | |
36dfe925 | 2127 | r = simple_read_from_buffer(ubuf, cnt, ppos, buf, r); |
bc0c38d1 SR |
2128 | |
2129 | kfree(buf); | |
bc0c38d1 SR |
2130 | return r; |
2131 | } | |
2132 | ||
adf9f195 FW |
2133 | /* Try to assign a tracer specific option */ |
2134 | static int set_tracer_option(struct tracer *trace, char *cmp, int neg) | |
2135 | { | |
7770841e | 2136 | struct tracer_flags *tracer_flags = trace->flags; |
adf9f195 FW |
2137 | struct tracer_opt *opts = NULL; |
2138 | int ret = 0, i = 0; | |
2139 | int len; | |
2140 | ||
7770841e Z |
2141 | for (i = 0; tracer_flags->opts[i].name; i++) { |
2142 | opts = &tracer_flags->opts[i]; | |
adf9f195 FW |
2143 | len = strlen(opts->name); |
2144 | ||
2145 | if (strncmp(cmp, opts->name, len) == 0) { | |
7770841e | 2146 | ret = trace->set_flag(tracer_flags->val, |
adf9f195 FW |
2147 | opts->bit, !neg); |
2148 | break; | |
2149 | } | |
2150 | } | |
2151 | /* Not found */ | |
7770841e | 2152 | if (!tracer_flags->opts[i].name) |
adf9f195 FW |
2153 | return -EINVAL; |
2154 | ||
2155 | /* Refused to handle */ | |
2156 | if (ret) | |
2157 | return ret; | |
2158 | ||
2159 | if (neg) | |
7770841e | 2160 | tracer_flags->val &= ~opts->bit; |
adf9f195 | 2161 | else |
7770841e | 2162 | tracer_flags->val |= opts->bit; |
adf9f195 FW |
2163 | |
2164 | return 0; | |
2165 | } | |
2166 | ||
af4617bd SR |
2167 | static void set_tracer_flags(unsigned int mask, int enabled) |
2168 | { | |
2169 | /* do nothing if flag is already set */ | |
2170 | if (!!(trace_flags & mask) == !!enabled) | |
2171 | return; | |
2172 | ||
2173 | if (enabled) | |
2174 | trace_flags |= mask; | |
2175 | else | |
2176 | trace_flags &= ~mask; | |
af4617bd SR |
2177 | } |
2178 | ||
bc0c38d1 | 2179 | static ssize_t |
ee6bce52 | 2180 | tracing_trace_options_write(struct file *filp, const char __user *ubuf, |
bc0c38d1 SR |
2181 | size_t cnt, loff_t *ppos) |
2182 | { | |
2183 | char buf[64]; | |
2184 | char *cmp = buf; | |
2185 | int neg = 0; | |
adf9f195 | 2186 | int ret; |
bc0c38d1 SR |
2187 | int i; |
2188 | ||
cffae437 SR |
2189 | if (cnt >= sizeof(buf)) |
2190 | return -EINVAL; | |
bc0c38d1 SR |
2191 | |
2192 | if (copy_from_user(&buf, ubuf, cnt)) | |
2193 | return -EFAULT; | |
2194 | ||
2195 | buf[cnt] = 0; | |
2196 | ||
2197 | if (strncmp(buf, "no", 2) == 0) { | |
2198 | neg = 1; | |
2199 | cmp += 2; | |
2200 | } | |
2201 | ||
2202 | for (i = 0; trace_options[i]; i++) { | |
2203 | int len = strlen(trace_options[i]); | |
2204 | ||
2205 | if (strncmp(cmp, trace_options[i], len) == 0) { | |
af4617bd | 2206 | set_tracer_flags(1 << i, !neg); |
bc0c38d1 SR |
2207 | break; |
2208 | } | |
2209 | } | |
adf9f195 FW |
2210 | |
2211 | /* If no option could be set, test the specific tracer options */ | |
2212 | if (!trace_options[i]) { | |
d8e83d26 | 2213 | mutex_lock(&trace_types_lock); |
adf9f195 | 2214 | ret = set_tracer_option(current_trace, cmp, neg); |
d8e83d26 | 2215 | mutex_unlock(&trace_types_lock); |
adf9f195 FW |
2216 | if (ret) |
2217 | return ret; | |
2218 | } | |
bc0c38d1 SR |
2219 | |
2220 | filp->f_pos += cnt; | |
2221 | ||
2222 | return cnt; | |
2223 | } | |
2224 | ||
5e2336a0 | 2225 | static const struct file_operations tracing_iter_fops = { |
c7078de1 | 2226 | .open = tracing_open_generic, |
ee6bce52 SR |
2227 | .read = tracing_trace_options_read, |
2228 | .write = tracing_trace_options_write, | |
bc0c38d1 SR |
2229 | }; |
2230 | ||
7bd2f24c IM |
2231 | static const char readme_msg[] = |
2232 | "tracing mini-HOWTO:\n\n" | |
156f5a78 GL |
2233 | "# mount -t debugfs nodev /sys/kernel/debug\n\n" |
2234 | "# cat /sys/kernel/debug/tracing/available_tracers\n" | |
bc2b6871 | 2235 | "wakeup preemptirqsoff preemptoff irqsoff function sched_switch nop\n\n" |
156f5a78 | 2236 | "# cat /sys/kernel/debug/tracing/current_tracer\n" |
bc2b6871 | 2237 | "nop\n" |
156f5a78 GL |
2238 | "# echo sched_switch > /sys/kernel/debug/tracing/current_tracer\n" |
2239 | "# cat /sys/kernel/debug/tracing/current_tracer\n" | |
7bd2f24c | 2240 | "sched_switch\n" |
156f5a78 | 2241 | "# cat /sys/kernel/debug/tracing/trace_options\n" |
7bd2f24c | 2242 | "noprint-parent nosym-offset nosym-addr noverbose\n" |
156f5a78 GL |
2243 | "# echo print-parent > /sys/kernel/debug/tracing/trace_options\n" |
2244 | "# echo 1 > /sys/kernel/debug/tracing/tracing_enabled\n" | |
2245 | "# cat /sys/kernel/debug/tracing/trace > /tmp/trace.txt\n" | |
2246 | "# echo 0 > /sys/kernel/debug/tracing/tracing_enabled\n" | |
7bd2f24c IM |
2247 | ; |
2248 | ||
2249 | static ssize_t | |
2250 | tracing_readme_read(struct file *filp, char __user *ubuf, | |
2251 | size_t cnt, loff_t *ppos) | |
2252 | { | |
2253 | return simple_read_from_buffer(ubuf, cnt, ppos, | |
2254 | readme_msg, strlen(readme_msg)); | |
2255 | } | |
2256 | ||
5e2336a0 | 2257 | static const struct file_operations tracing_readme_fops = { |
c7078de1 IM |
2258 | .open = tracing_open_generic, |
2259 | .read = tracing_readme_read, | |
7bd2f24c IM |
2260 | }; |
2261 | ||
69abe6a5 AP |
2262 | static ssize_t |
2263 | tracing_saved_cmdlines_read(struct file *file, char __user *ubuf, | |
2264 | size_t cnt, loff_t *ppos) | |
2265 | { | |
2266 | char *buf_comm; | |
2267 | char *file_buf; | |
2268 | char *buf; | |
2269 | int len = 0; | |
2270 | int pid; | |
2271 | int i; | |
2272 | ||
2273 | file_buf = kmalloc(SAVED_CMDLINES*(16+TASK_COMM_LEN), GFP_KERNEL); | |
2274 | if (!file_buf) | |
2275 | return -ENOMEM; | |
2276 | ||
2277 | buf_comm = kmalloc(TASK_COMM_LEN, GFP_KERNEL); | |
2278 | if (!buf_comm) { | |
2279 | kfree(file_buf); | |
2280 | return -ENOMEM; | |
2281 | } | |
2282 | ||
2283 | buf = file_buf; | |
2284 | ||
2285 | for (i = 0; i < SAVED_CMDLINES; i++) { | |
2286 | int r; | |
2287 | ||
2288 | pid = map_cmdline_to_pid[i]; | |
2289 | if (pid == -1 || pid == NO_CMDLINE_MAP) | |
2290 | continue; | |
2291 | ||
2292 | trace_find_cmdline(pid, buf_comm); | |
2293 | r = sprintf(buf, "%d %s\n", pid, buf_comm); | |
2294 | buf += r; | |
2295 | len += r; | |
2296 | } | |
2297 | ||
2298 | len = simple_read_from_buffer(ubuf, cnt, ppos, | |
2299 | file_buf, len); | |
2300 | ||
2301 | kfree(file_buf); | |
2302 | kfree(buf_comm); | |
2303 | ||
2304 | return len; | |
2305 | } | |
2306 | ||
2307 | static const struct file_operations tracing_saved_cmdlines_fops = { | |
2308 | .open = tracing_open_generic, | |
2309 | .read = tracing_saved_cmdlines_read, | |
2310 | }; | |
2311 | ||
bc0c38d1 SR |
2312 | static ssize_t |
2313 | tracing_ctrl_read(struct file *filp, char __user *ubuf, | |
2314 | size_t cnt, loff_t *ppos) | |
2315 | { | |
bc0c38d1 SR |
2316 | char buf[64]; |
2317 | int r; | |
2318 | ||
9036990d | 2319 | r = sprintf(buf, "%u\n", tracer_enabled); |
4e3c3333 | 2320 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, r); |
bc0c38d1 SR |
2321 | } |
2322 | ||
2323 | static ssize_t | |
2324 | tracing_ctrl_write(struct file *filp, const char __user *ubuf, | |
2325 | size_t cnt, loff_t *ppos) | |
2326 | { | |
2327 | struct trace_array *tr = filp->private_data; | |
bc0c38d1 | 2328 | char buf[64]; |
5e39841c | 2329 | unsigned long val; |
c6caeeb1 | 2330 | int ret; |
bc0c38d1 | 2331 | |
cffae437 SR |
2332 | if (cnt >= sizeof(buf)) |
2333 | return -EINVAL; | |
bc0c38d1 SR |
2334 | |
2335 | if (copy_from_user(&buf, ubuf, cnt)) | |
2336 | return -EFAULT; | |
2337 | ||
2338 | buf[cnt] = 0; | |
2339 | ||
c6caeeb1 SR |
2340 | ret = strict_strtoul(buf, 10, &val); |
2341 | if (ret < 0) | |
2342 | return ret; | |
bc0c38d1 SR |
2343 | |
2344 | val = !!val; | |
2345 | ||
2346 | mutex_lock(&trace_types_lock); | |
9036990d SR |
2347 | if (tracer_enabled ^ val) { |
2348 | if (val) { | |
bc0c38d1 | 2349 | tracer_enabled = 1; |
9036990d SR |
2350 | if (current_trace->start) |
2351 | current_trace->start(tr); | |
2352 | tracing_start(); | |
2353 | } else { | |
bc0c38d1 | 2354 | tracer_enabled = 0; |
9036990d SR |
2355 | tracing_stop(); |
2356 | if (current_trace->stop) | |
2357 | current_trace->stop(tr); | |
2358 | } | |
bc0c38d1 SR |
2359 | } |
2360 | mutex_unlock(&trace_types_lock); | |
2361 | ||
2362 | filp->f_pos += cnt; | |
2363 | ||
2364 | return cnt; | |
2365 | } | |
2366 | ||
2367 | static ssize_t | |
2368 | tracing_set_trace_read(struct file *filp, char __user *ubuf, | |
2369 | size_t cnt, loff_t *ppos) | |
2370 | { | |
2371 | char buf[max_tracer_type_len+2]; | |
2372 | int r; | |
2373 | ||
2374 | mutex_lock(&trace_types_lock); | |
2375 | if (current_trace) | |
2376 | r = sprintf(buf, "%s\n", current_trace->name); | |
2377 | else | |
2378 | r = sprintf(buf, "\n"); | |
2379 | mutex_unlock(&trace_types_lock); | |
2380 | ||
4bf39a94 | 2381 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, r); |
bc0c38d1 SR |
2382 | } |
2383 | ||
b6f11df2 ACM |
2384 | int tracer_init(struct tracer *t, struct trace_array *tr) |
2385 | { | |
2386 | tracing_reset_online_cpus(tr); | |
2387 | return t->init(tr); | |
2388 | } | |
2389 | ||
73c5162a SR |
2390 | static int tracing_resize_ring_buffer(unsigned long size) |
2391 | { | |
2392 | int ret; | |
2393 | ||
2394 | /* | |
2395 | * If kernel or user changes the size of the ring buffer | |
a123c52b SR |
2396 | * we use the size that was given, and we can forget about |
2397 | * expanding it later. | |
73c5162a SR |
2398 | */ |
2399 | ring_buffer_expanded = 1; | |
2400 | ||
2401 | ret = ring_buffer_resize(global_trace.buffer, size); | |
2402 | if (ret < 0) | |
2403 | return ret; | |
2404 | ||
2405 | ret = ring_buffer_resize(max_tr.buffer, size); | |
2406 | if (ret < 0) { | |
2407 | int r; | |
2408 | ||
2409 | r = ring_buffer_resize(global_trace.buffer, | |
2410 | global_trace.entries); | |
2411 | if (r < 0) { | |
a123c52b SR |
2412 | /* |
2413 | * AARGH! We are left with different | |
2414 | * size max buffer!!!! | |
2415 | * The max buffer is our "snapshot" buffer. | |
2416 | * When a tracer needs a snapshot (one of the | |
2417 | * latency tracers), it swaps the max buffer | |
2418 | * with the saved snap shot. We succeeded to | |
2419 | * update the size of the main buffer, but failed to | |
2420 | * update the size of the max buffer. But when we tried | |
2421 | * to reset the main buffer to the original size, we | |
2422 | * failed there too. This is very unlikely to | |
2423 | * happen, but if it does, warn and kill all | |
2424 | * tracing. | |
2425 | */ | |
73c5162a SR |
2426 | WARN_ON(1); |
2427 | tracing_disabled = 1; | |
2428 | } | |
2429 | return ret; | |
2430 | } | |
2431 | ||
2432 | global_trace.entries = size; | |
2433 | ||
2434 | return ret; | |
2435 | } | |
2436 | ||
1852fcce SR |
2437 | /** |
2438 | * tracing_update_buffers - used by tracing facility to expand ring buffers | |
2439 | * | |
2440 | * To save on memory when the tracing is never used on a system with it | |
2441 | * configured in. The ring buffers are set to a minimum size. But once | |
2442 | * a user starts to use the tracing facility, then they need to grow | |
2443 | * to their default size. | |
2444 | * | |
2445 | * This function is to be called when a tracer is about to be used. | |
2446 | */ | |
2447 | int tracing_update_buffers(void) | |
2448 | { | |
2449 | int ret = 0; | |
2450 | ||
1027fcb2 | 2451 | mutex_lock(&trace_types_lock); |
1852fcce SR |
2452 | if (!ring_buffer_expanded) |
2453 | ret = tracing_resize_ring_buffer(trace_buf_size); | |
1027fcb2 | 2454 | mutex_unlock(&trace_types_lock); |
1852fcce SR |
2455 | |
2456 | return ret; | |
2457 | } | |
2458 | ||
577b785f SR |
2459 | struct trace_option_dentry; |
2460 | ||
2461 | static struct trace_option_dentry * | |
2462 | create_trace_option_files(struct tracer *tracer); | |
2463 | ||
2464 | static void | |
2465 | destroy_trace_option_files(struct trace_option_dentry *topts); | |
2466 | ||
b2821ae6 | 2467 | static int tracing_set_tracer(const char *buf) |
bc0c38d1 | 2468 | { |
577b785f | 2469 | static struct trace_option_dentry *topts; |
bc0c38d1 SR |
2470 | struct trace_array *tr = &global_trace; |
2471 | struct tracer *t; | |
d9e54076 | 2472 | int ret = 0; |
bc0c38d1 | 2473 | |
1027fcb2 SR |
2474 | mutex_lock(&trace_types_lock); |
2475 | ||
73c5162a SR |
2476 | if (!ring_buffer_expanded) { |
2477 | ret = tracing_resize_ring_buffer(trace_buf_size); | |
2478 | if (ret < 0) | |
59f586db | 2479 | goto out; |
73c5162a SR |
2480 | ret = 0; |
2481 | } | |
2482 | ||
bc0c38d1 SR |
2483 | for (t = trace_types; t; t = t->next) { |
2484 | if (strcmp(t->name, buf) == 0) | |
2485 | break; | |
2486 | } | |
c2931e05 FW |
2487 | if (!t) { |
2488 | ret = -EINVAL; | |
2489 | goto out; | |
2490 | } | |
2491 | if (t == current_trace) | |
bc0c38d1 SR |
2492 | goto out; |
2493 | ||
9f029e83 | 2494 | trace_branch_disable(); |
bc0c38d1 SR |
2495 | if (current_trace && current_trace->reset) |
2496 | current_trace->reset(tr); | |
2497 | ||
577b785f SR |
2498 | destroy_trace_option_files(topts); |
2499 | ||
bc0c38d1 | 2500 | current_trace = t; |
577b785f SR |
2501 | |
2502 | topts = create_trace_option_files(current_trace); | |
2503 | ||
1c80025a | 2504 | if (t->init) { |
b6f11df2 | 2505 | ret = tracer_init(t, tr); |
1c80025a FW |
2506 | if (ret) |
2507 | goto out; | |
2508 | } | |
bc0c38d1 | 2509 | |
9f029e83 | 2510 | trace_branch_enable(tr); |
bc0c38d1 SR |
2511 | out: |
2512 | mutex_unlock(&trace_types_lock); | |
2513 | ||
d9e54076 PZ |
2514 | return ret; |
2515 | } | |
2516 | ||
2517 | static ssize_t | |
2518 | tracing_set_trace_write(struct file *filp, const char __user *ubuf, | |
2519 | size_t cnt, loff_t *ppos) | |
2520 | { | |
2521 | char buf[max_tracer_type_len+1]; | |
2522 | int i; | |
2523 | size_t ret; | |
e6e7a65a FW |
2524 | int err; |
2525 | ||
2526 | ret = cnt; | |
d9e54076 PZ |
2527 | |
2528 | if (cnt > max_tracer_type_len) | |
2529 | cnt = max_tracer_type_len; | |
2530 | ||
2531 | if (copy_from_user(&buf, ubuf, cnt)) | |
2532 | return -EFAULT; | |
2533 | ||
2534 | buf[cnt] = 0; | |
2535 | ||
2536 | /* strip ending whitespace. */ | |
2537 | for (i = cnt - 1; i > 0 && isspace(buf[i]); i--) | |
2538 | buf[i] = 0; | |
2539 | ||
e6e7a65a FW |
2540 | err = tracing_set_tracer(buf); |
2541 | if (err) | |
2542 | return err; | |
d9e54076 | 2543 | |
e6e7a65a | 2544 | filp->f_pos += ret; |
bc0c38d1 | 2545 | |
c2931e05 | 2546 | return ret; |
bc0c38d1 SR |
2547 | } |
2548 | ||
2549 | static ssize_t | |
2550 | tracing_max_lat_read(struct file *filp, char __user *ubuf, | |
2551 | size_t cnt, loff_t *ppos) | |
2552 | { | |
2553 | unsigned long *ptr = filp->private_data; | |
2554 | char buf[64]; | |
2555 | int r; | |
2556 | ||
cffae437 | 2557 | r = snprintf(buf, sizeof(buf), "%ld\n", |
bc0c38d1 | 2558 | *ptr == (unsigned long)-1 ? -1 : nsecs_to_usecs(*ptr)); |
cffae437 SR |
2559 | if (r > sizeof(buf)) |
2560 | r = sizeof(buf); | |
4bf39a94 | 2561 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, r); |
bc0c38d1 SR |
2562 | } |
2563 | ||
2564 | static ssize_t | |
2565 | tracing_max_lat_write(struct file *filp, const char __user *ubuf, | |
2566 | size_t cnt, loff_t *ppos) | |
2567 | { | |
5e39841c | 2568 | unsigned long *ptr = filp->private_data; |
bc0c38d1 | 2569 | char buf[64]; |
5e39841c | 2570 | unsigned long val; |
c6caeeb1 | 2571 | int ret; |
bc0c38d1 | 2572 | |
cffae437 SR |
2573 | if (cnt >= sizeof(buf)) |
2574 | return -EINVAL; | |
bc0c38d1 SR |
2575 | |
2576 | if (copy_from_user(&buf, ubuf, cnt)) | |
2577 | return -EFAULT; | |
2578 | ||
2579 | buf[cnt] = 0; | |
2580 | ||
c6caeeb1 SR |
2581 | ret = strict_strtoul(buf, 10, &val); |
2582 | if (ret < 0) | |
2583 | return ret; | |
bc0c38d1 SR |
2584 | |
2585 | *ptr = val * 1000; | |
2586 | ||
2587 | return cnt; | |
2588 | } | |
2589 | ||
b3806b43 SR |
2590 | static int tracing_open_pipe(struct inode *inode, struct file *filp) |
2591 | { | |
b04cc6b1 | 2592 | long cpu_file = (long) inode->i_private; |
b3806b43 | 2593 | struct trace_iterator *iter; |
b04cc6b1 | 2594 | int ret = 0; |
b3806b43 SR |
2595 | |
2596 | if (tracing_disabled) | |
2597 | return -ENODEV; | |
2598 | ||
b04cc6b1 FW |
2599 | mutex_lock(&trace_types_lock); |
2600 | ||
2601 | /* We only allow one reader per cpu */ | |
2602 | if (cpu_file == TRACE_PIPE_ALL_CPU) { | |
2603 | if (!cpumask_empty(tracing_reader_cpumask)) { | |
2604 | ret = -EBUSY; | |
2605 | goto out; | |
2606 | } | |
2607 | cpumask_setall(tracing_reader_cpumask); | |
2608 | } else { | |
2609 | if (!cpumask_test_cpu(cpu_file, tracing_reader_cpumask)) | |
2610 | cpumask_set_cpu(cpu_file, tracing_reader_cpumask); | |
2611 | else { | |
2612 | ret = -EBUSY; | |
2613 | goto out; | |
2614 | } | |
b3806b43 SR |
2615 | } |
2616 | ||
2617 | /* create a buffer to store the information to pass to userspace */ | |
2618 | iter = kzalloc(sizeof(*iter), GFP_KERNEL); | |
b04cc6b1 FW |
2619 | if (!iter) { |
2620 | ret = -ENOMEM; | |
2621 | goto out; | |
2622 | } | |
b3806b43 | 2623 | |
d7350c3f FW |
2624 | /* |
2625 | * We make a copy of the current tracer to avoid concurrent | |
2626 | * changes on it while we are reading. | |
2627 | */ | |
2628 | iter->trace = kmalloc(sizeof(*iter->trace), GFP_KERNEL); | |
2629 | if (!iter->trace) { | |
2630 | ret = -ENOMEM; | |
2631 | goto fail; | |
2632 | } | |
2633 | if (current_trace) | |
2634 | *iter->trace = *current_trace; | |
2635 | ||
4462344e | 2636 | if (!alloc_cpumask_var(&iter->started, GFP_KERNEL)) { |
b04cc6b1 | 2637 | ret = -ENOMEM; |
d7350c3f | 2638 | goto fail; |
4462344e RR |
2639 | } |
2640 | ||
a309720c | 2641 | /* trace pipe does not show start of buffer */ |
4462344e | 2642 | cpumask_setall(iter->started); |
a309720c | 2643 | |
112f38a7 SR |
2644 | if (trace_flags & TRACE_ITER_LATENCY_FMT) |
2645 | iter->iter_flags |= TRACE_FILE_LAT_FMT; | |
2646 | ||
b04cc6b1 | 2647 | iter->cpu_file = cpu_file; |
b3806b43 | 2648 | iter->tr = &global_trace; |
d7350c3f | 2649 | mutex_init(&iter->mutex); |
b3806b43 SR |
2650 | filp->private_data = iter; |
2651 | ||
107bad8b SR |
2652 | if (iter->trace->pipe_open) |
2653 | iter->trace->pipe_open(iter); | |
107bad8b | 2654 | |
b04cc6b1 FW |
2655 | out: |
2656 | mutex_unlock(&trace_types_lock); | |
2657 | return ret; | |
d7350c3f FW |
2658 | |
2659 | fail: | |
2660 | kfree(iter->trace); | |
2661 | kfree(iter); | |
2662 | mutex_unlock(&trace_types_lock); | |
2663 | return ret; | |
b3806b43 SR |
2664 | } |
2665 | ||
2666 | static int tracing_release_pipe(struct inode *inode, struct file *file) | |
2667 | { | |
2668 | struct trace_iterator *iter = file->private_data; | |
2669 | ||
b04cc6b1 FW |
2670 | mutex_lock(&trace_types_lock); |
2671 | ||
2672 | if (iter->cpu_file == TRACE_PIPE_ALL_CPU) | |
2673 | cpumask_clear(tracing_reader_cpumask); | |
2674 | else | |
2675 | cpumask_clear_cpu(iter->cpu_file, tracing_reader_cpumask); | |
2676 | ||
2677 | mutex_unlock(&trace_types_lock); | |
2678 | ||
4462344e | 2679 | free_cpumask_var(iter->started); |
d7350c3f FW |
2680 | mutex_destroy(&iter->mutex); |
2681 | kfree(iter->trace); | |
b3806b43 | 2682 | kfree(iter); |
b3806b43 SR |
2683 | |
2684 | return 0; | |
2685 | } | |
2686 | ||
2a2cc8f7 SSP |
2687 | static unsigned int |
2688 | tracing_poll_pipe(struct file *filp, poll_table *poll_table) | |
2689 | { | |
2690 | struct trace_iterator *iter = filp->private_data; | |
2691 | ||
2692 | if (trace_flags & TRACE_ITER_BLOCK) { | |
2693 | /* | |
2694 | * Always select as readable when in blocking mode | |
2695 | */ | |
2696 | return POLLIN | POLLRDNORM; | |
afc2abc0 | 2697 | } else { |
2a2cc8f7 SSP |
2698 | if (!trace_empty(iter)) |
2699 | return POLLIN | POLLRDNORM; | |
2700 | poll_wait(filp, &trace_wait, poll_table); | |
2701 | if (!trace_empty(iter)) | |
2702 | return POLLIN | POLLRDNORM; | |
2703 | ||
2704 | return 0; | |
2705 | } | |
2706 | } | |
2707 | ||
6eaaa5d5 FW |
2708 | |
2709 | void default_wait_pipe(struct trace_iterator *iter) | |
2710 | { | |
2711 | DEFINE_WAIT(wait); | |
2712 | ||
2713 | prepare_to_wait(&trace_wait, &wait, TASK_INTERRUPTIBLE); | |
2714 | ||
2715 | if (trace_empty(iter)) | |
2716 | schedule(); | |
2717 | ||
2718 | finish_wait(&trace_wait, &wait); | |
2719 | } | |
2720 | ||
2721 | /* | |
2722 | * This is a make-shift waitqueue. | |
2723 | * A tracer might use this callback on some rare cases: | |
2724 | * | |
2725 | * 1) the current tracer might hold the runqueue lock when it wakes up | |
2726 | * a reader, hence a deadlock (sched, function, and function graph tracers) | |
2727 | * 2) the function tracers, trace all functions, we don't want | |
2728 | * the overhead of calling wake_up and friends | |
2729 | * (and tracing them too) | |
2730 | * | |
2731 | * Anyway, this is really very primitive wakeup. | |
2732 | */ | |
2733 | void poll_wait_pipe(struct trace_iterator *iter) | |
2734 | { | |
2735 | set_current_state(TASK_INTERRUPTIBLE); | |
2736 | /* sleep for 100 msecs, and try again. */ | |
2737 | schedule_timeout(HZ / 10); | |
2738 | } | |
2739 | ||
ff98781b EGM |
2740 | /* Must be called with trace_types_lock mutex held. */ |
2741 | static int tracing_wait_pipe(struct file *filp) | |
b3806b43 SR |
2742 | { |
2743 | struct trace_iterator *iter = filp->private_data; | |
b3806b43 | 2744 | |
b3806b43 | 2745 | while (trace_empty(iter)) { |
2dc8f095 | 2746 | |
107bad8b | 2747 | if ((filp->f_flags & O_NONBLOCK)) { |
ff98781b | 2748 | return -EAGAIN; |
107bad8b | 2749 | } |
2dc8f095 | 2750 | |
d7350c3f | 2751 | mutex_unlock(&iter->mutex); |
107bad8b | 2752 | |
6eaaa5d5 | 2753 | iter->trace->wait_pipe(iter); |
b3806b43 | 2754 | |
d7350c3f | 2755 | mutex_lock(&iter->mutex); |
107bad8b | 2756 | |
6eaaa5d5 | 2757 | if (signal_pending(current)) |
ff98781b | 2758 | return -EINTR; |
b3806b43 SR |
2759 | |
2760 | /* | |
2761 | * We block until we read something and tracing is disabled. | |
2762 | * We still block if tracing is disabled, but we have never | |
2763 | * read anything. This allows a user to cat this file, and | |
2764 | * then enable tracing. But after we have read something, | |
2765 | * we give an EOF when tracing is again disabled. | |
2766 | * | |
2767 | * iter->pos will be 0 if we haven't read anything. | |
2768 | */ | |
2769 | if (!tracer_enabled && iter->pos) | |
2770 | break; | |
b3806b43 SR |
2771 | } |
2772 | ||
ff98781b EGM |
2773 | return 1; |
2774 | } | |
2775 | ||
2776 | /* | |
2777 | * Consumer reader. | |
2778 | */ | |
2779 | static ssize_t | |
2780 | tracing_read_pipe(struct file *filp, char __user *ubuf, | |
2781 | size_t cnt, loff_t *ppos) | |
2782 | { | |
2783 | struct trace_iterator *iter = filp->private_data; | |
d7350c3f | 2784 | static struct tracer *old_tracer; |
ff98781b EGM |
2785 | ssize_t sret; |
2786 | ||
2787 | /* return any leftover data */ | |
2788 | sret = trace_seq_to_user(&iter->seq, ubuf, cnt); | |
2789 | if (sret != -EBUSY) | |
2790 | return sret; | |
2791 | ||
f9520750 | 2792 | trace_seq_init(&iter->seq); |
ff98781b | 2793 | |
d7350c3f | 2794 | /* copy the tracer to avoid using a global lock all around */ |
ff98781b | 2795 | mutex_lock(&trace_types_lock); |
d7350c3f FW |
2796 | if (unlikely(old_tracer != current_trace && current_trace)) { |
2797 | old_tracer = current_trace; | |
2798 | *iter->trace = *current_trace; | |
2799 | } | |
2800 | mutex_unlock(&trace_types_lock); | |
2801 | ||
2802 | /* | |
2803 | * Avoid more than one consumer on a single file descriptor | |
2804 | * This is just a matter of traces coherency, the ring buffer itself | |
2805 | * is protected. | |
2806 | */ | |
2807 | mutex_lock(&iter->mutex); | |
ff98781b EGM |
2808 | if (iter->trace->read) { |
2809 | sret = iter->trace->read(iter, filp, ubuf, cnt, ppos); | |
2810 | if (sret) | |
2811 | goto out; | |
2812 | } | |
2813 | ||
2814 | waitagain: | |
2815 | sret = tracing_wait_pipe(filp); | |
2816 | if (sret <= 0) | |
2817 | goto out; | |
2818 | ||
b3806b43 | 2819 | /* stop when tracing is finished */ |
ff98781b EGM |
2820 | if (trace_empty(iter)) { |
2821 | sret = 0; | |
107bad8b | 2822 | goto out; |
ff98781b | 2823 | } |
b3806b43 SR |
2824 | |
2825 | if (cnt >= PAGE_SIZE) | |
2826 | cnt = PAGE_SIZE - 1; | |
2827 | ||
53d0aa77 | 2828 | /* reset all but tr, trace, and overruns */ |
53d0aa77 SR |
2829 | memset(&iter->seq, 0, |
2830 | sizeof(struct trace_iterator) - | |
2831 | offsetof(struct trace_iterator, seq)); | |
4823ed7e | 2832 | iter->pos = -1; |
b3806b43 | 2833 | |
4f535968 | 2834 | trace_event_read_lock(); |
088b1e42 | 2835 | while (find_next_entry_inc(iter) != NULL) { |
2c4f035f | 2836 | enum print_line_t ret; |
088b1e42 SR |
2837 | int len = iter->seq.len; |
2838 | ||
f9896bf3 | 2839 | ret = print_trace_line(iter); |
2c4f035f | 2840 | if (ret == TRACE_TYPE_PARTIAL_LINE) { |
088b1e42 SR |
2841 | /* don't print partial lines */ |
2842 | iter->seq.len = len; | |
b3806b43 | 2843 | break; |
088b1e42 | 2844 | } |
b91facc3 FW |
2845 | if (ret != TRACE_TYPE_NO_CONSUME) |
2846 | trace_consume(iter); | |
b3806b43 SR |
2847 | |
2848 | if (iter->seq.len >= cnt) | |
2849 | break; | |
b3806b43 | 2850 | } |
4f535968 | 2851 | trace_event_read_unlock(); |
b3806b43 | 2852 | |
b3806b43 | 2853 | /* Now copy what we have to the user */ |
6c6c2796 PP |
2854 | sret = trace_seq_to_user(&iter->seq, ubuf, cnt); |
2855 | if (iter->seq.readpos >= iter->seq.len) | |
f9520750 | 2856 | trace_seq_init(&iter->seq); |
9ff4b974 PP |
2857 | |
2858 | /* | |
2859 | * If there was nothing to send to user, inspite of consuming trace | |
2860 | * entries, go back to wait for more entries. | |
2861 | */ | |
6c6c2796 | 2862 | if (sret == -EBUSY) |
9ff4b974 | 2863 | goto waitagain; |
b3806b43 | 2864 | |
107bad8b | 2865 | out: |
d7350c3f | 2866 | mutex_unlock(&iter->mutex); |
107bad8b | 2867 | |
6c6c2796 | 2868 | return sret; |
b3806b43 SR |
2869 | } |
2870 | ||
3c56819b EGM |
2871 | static void tracing_pipe_buf_release(struct pipe_inode_info *pipe, |
2872 | struct pipe_buffer *buf) | |
2873 | { | |
2874 | __free_page(buf->page); | |
2875 | } | |
2876 | ||
2877 | static void tracing_spd_release_pipe(struct splice_pipe_desc *spd, | |
2878 | unsigned int idx) | |
2879 | { | |
2880 | __free_page(spd->pages[idx]); | |
2881 | } | |
2882 | ||
2883 | static struct pipe_buf_operations tracing_pipe_buf_ops = { | |
34cd4998 SR |
2884 | .can_merge = 0, |
2885 | .map = generic_pipe_buf_map, | |
2886 | .unmap = generic_pipe_buf_unmap, | |
2887 | .confirm = generic_pipe_buf_confirm, | |
2888 | .release = tracing_pipe_buf_release, | |
2889 | .steal = generic_pipe_buf_steal, | |
2890 | .get = generic_pipe_buf_get, | |
3c56819b EGM |
2891 | }; |
2892 | ||
34cd4998 | 2893 | static size_t |
fa7c7f6e | 2894 | tracing_fill_pipe_page(size_t rem, struct trace_iterator *iter) |
34cd4998 SR |
2895 | { |
2896 | size_t count; | |
2897 | int ret; | |
2898 | ||
2899 | /* Seq buffer is page-sized, exactly what we need. */ | |
2900 | for (;;) { | |
2901 | count = iter->seq.len; | |
2902 | ret = print_trace_line(iter); | |
2903 | count = iter->seq.len - count; | |
2904 | if (rem < count) { | |
2905 | rem = 0; | |
2906 | iter->seq.len -= count; | |
2907 | break; | |
2908 | } | |
2909 | if (ret == TRACE_TYPE_PARTIAL_LINE) { | |
2910 | iter->seq.len -= count; | |
2911 | break; | |
2912 | } | |
2913 | ||
74e7ff8c LJ |
2914 | if (ret != TRACE_TYPE_NO_CONSUME) |
2915 | trace_consume(iter); | |
34cd4998 SR |
2916 | rem -= count; |
2917 | if (!find_next_entry_inc(iter)) { | |
2918 | rem = 0; | |
2919 | iter->ent = NULL; | |
2920 | break; | |
2921 | } | |
2922 | } | |
2923 | ||
2924 | return rem; | |
2925 | } | |
2926 | ||
3c56819b EGM |
2927 | static ssize_t tracing_splice_read_pipe(struct file *filp, |
2928 | loff_t *ppos, | |
2929 | struct pipe_inode_info *pipe, | |
2930 | size_t len, | |
2931 | unsigned int flags) | |
2932 | { | |
2933 | struct page *pages[PIPE_BUFFERS]; | |
2934 | struct partial_page partial[PIPE_BUFFERS]; | |
2935 | struct trace_iterator *iter = filp->private_data; | |
2936 | struct splice_pipe_desc spd = { | |
34cd4998 SR |
2937 | .pages = pages, |
2938 | .partial = partial, | |
2939 | .nr_pages = 0, /* This gets updated below. */ | |
2940 | .flags = flags, | |
2941 | .ops = &tracing_pipe_buf_ops, | |
2942 | .spd_release = tracing_spd_release_pipe, | |
3c56819b | 2943 | }; |
d7350c3f | 2944 | static struct tracer *old_tracer; |
3c56819b | 2945 | ssize_t ret; |
34cd4998 | 2946 | size_t rem; |
3c56819b EGM |
2947 | unsigned int i; |
2948 | ||
d7350c3f | 2949 | /* copy the tracer to avoid using a global lock all around */ |
3c56819b | 2950 | mutex_lock(&trace_types_lock); |
d7350c3f FW |
2951 | if (unlikely(old_tracer != current_trace && current_trace)) { |
2952 | old_tracer = current_trace; | |
2953 | *iter->trace = *current_trace; | |
2954 | } | |
2955 | mutex_unlock(&trace_types_lock); | |
2956 | ||
2957 | mutex_lock(&iter->mutex); | |
3c56819b EGM |
2958 | |
2959 | if (iter->trace->splice_read) { | |
2960 | ret = iter->trace->splice_read(iter, filp, | |
2961 | ppos, pipe, len, flags); | |
2962 | if (ret) | |
34cd4998 | 2963 | goto out_err; |
3c56819b EGM |
2964 | } |
2965 | ||
2966 | ret = tracing_wait_pipe(filp); | |
2967 | if (ret <= 0) | |
34cd4998 | 2968 | goto out_err; |
3c56819b EGM |
2969 | |
2970 | if (!iter->ent && !find_next_entry_inc(iter)) { | |
2971 | ret = -EFAULT; | |
34cd4998 | 2972 | goto out_err; |
3c56819b EGM |
2973 | } |
2974 | ||
4f535968 LJ |
2975 | trace_event_read_lock(); |
2976 | ||
3c56819b EGM |
2977 | /* Fill as many pages as possible. */ |
2978 | for (i = 0, rem = len; i < PIPE_BUFFERS && rem; i++) { | |
2979 | pages[i] = alloc_page(GFP_KERNEL); | |
34cd4998 SR |
2980 | if (!pages[i]) |
2981 | break; | |
3c56819b | 2982 | |
fa7c7f6e | 2983 | rem = tracing_fill_pipe_page(rem, iter); |
3c56819b EGM |
2984 | |
2985 | /* Copy the data into the page, so we can start over. */ | |
2986 | ret = trace_seq_to_buffer(&iter->seq, | |
2987 | page_address(pages[i]), | |
2988 | iter->seq.len); | |
2989 | if (ret < 0) { | |
2990 | __free_page(pages[i]); | |
2991 | break; | |
2992 | } | |
2993 | partial[i].offset = 0; | |
2994 | partial[i].len = iter->seq.len; | |
2995 | ||
f9520750 | 2996 | trace_seq_init(&iter->seq); |
3c56819b EGM |
2997 | } |
2998 | ||
4f535968 | 2999 | trace_event_read_unlock(); |
d7350c3f | 3000 | mutex_unlock(&iter->mutex); |
3c56819b EGM |
3001 | |
3002 | spd.nr_pages = i; | |
3003 | ||
3004 | return splice_to_pipe(pipe, &spd); | |
3005 | ||
34cd4998 | 3006 | out_err: |
d7350c3f | 3007 | mutex_unlock(&iter->mutex); |
3c56819b EGM |
3008 | |
3009 | return ret; | |
3010 | } | |
3011 | ||
a98a3c3f SR |
3012 | static ssize_t |
3013 | tracing_entries_read(struct file *filp, char __user *ubuf, | |
3014 | size_t cnt, loff_t *ppos) | |
3015 | { | |
3016 | struct trace_array *tr = filp->private_data; | |
db526ca3 | 3017 | char buf[96]; |
a98a3c3f SR |
3018 | int r; |
3019 | ||
db526ca3 SR |
3020 | mutex_lock(&trace_types_lock); |
3021 | if (!ring_buffer_expanded) | |
3022 | r = sprintf(buf, "%lu (expanded: %lu)\n", | |
3023 | tr->entries >> 10, | |
3024 | trace_buf_size >> 10); | |
3025 | else | |
3026 | r = sprintf(buf, "%lu\n", tr->entries >> 10); | |
3027 | mutex_unlock(&trace_types_lock); | |
3028 | ||
a98a3c3f SR |
3029 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, r); |
3030 | } | |
3031 | ||
3032 | static ssize_t | |
3033 | tracing_entries_write(struct file *filp, const char __user *ubuf, | |
3034 | size_t cnt, loff_t *ppos) | |
3035 | { | |
3036 | unsigned long val; | |
3037 | char buf[64]; | |
bf5e6519 | 3038 | int ret, cpu; |
a98a3c3f | 3039 | |
cffae437 SR |
3040 | if (cnt >= sizeof(buf)) |
3041 | return -EINVAL; | |
a98a3c3f SR |
3042 | |
3043 | if (copy_from_user(&buf, ubuf, cnt)) | |
3044 | return -EFAULT; | |
3045 | ||
3046 | buf[cnt] = 0; | |
3047 | ||
c6caeeb1 SR |
3048 | ret = strict_strtoul(buf, 10, &val); |
3049 | if (ret < 0) | |
3050 | return ret; | |
a98a3c3f SR |
3051 | |
3052 | /* must have at least 1 entry */ | |
3053 | if (!val) | |
3054 | return -EINVAL; | |
3055 | ||
3056 | mutex_lock(&trace_types_lock); | |
3057 | ||
c76f0694 | 3058 | tracing_stop(); |
a98a3c3f | 3059 | |
bf5e6519 SR |
3060 | /* disable all cpu buffers */ |
3061 | for_each_tracing_cpu(cpu) { | |
3062 | if (global_trace.data[cpu]) | |
3063 | atomic_inc(&global_trace.data[cpu]->disabled); | |
3064 | if (max_tr.data[cpu]) | |
3065 | atomic_inc(&max_tr.data[cpu]->disabled); | |
3066 | } | |
3067 | ||
1696b2b0 SR |
3068 | /* value is in KB */ |
3069 | val <<= 10; | |
3070 | ||
3928a8a2 | 3071 | if (val != global_trace.entries) { |
73c5162a | 3072 | ret = tracing_resize_ring_buffer(val); |
3928a8a2 SR |
3073 | if (ret < 0) { |
3074 | cnt = ret; | |
3eefae99 SR |
3075 | goto out; |
3076 | } | |
a98a3c3f SR |
3077 | } |
3078 | ||
3079 | filp->f_pos += cnt; | |
3080 | ||
19384c03 SR |
3081 | /* If check pages failed, return ENOMEM */ |
3082 | if (tracing_disabled) | |
3083 | cnt = -ENOMEM; | |
a98a3c3f | 3084 | out: |
bf5e6519 SR |
3085 | for_each_tracing_cpu(cpu) { |
3086 | if (global_trace.data[cpu]) | |
3087 | atomic_dec(&global_trace.data[cpu]->disabled); | |
3088 | if (max_tr.data[cpu]) | |
3089 | atomic_dec(&max_tr.data[cpu]->disabled); | |
3090 | } | |
3091 | ||
c76f0694 | 3092 | tracing_start(); |
a98a3c3f SR |
3093 | max_tr.entries = global_trace.entries; |
3094 | mutex_unlock(&trace_types_lock); | |
3095 | ||
3096 | return cnt; | |
3097 | } | |
3098 | ||
5bf9a1ee PP |
3099 | static int mark_printk(const char *fmt, ...) |
3100 | { | |
3101 | int ret; | |
3102 | va_list args; | |
3103 | va_start(args, fmt); | |
40ce74f1 | 3104 | ret = trace_vprintk(0, fmt, args); |
5bf9a1ee PP |
3105 | va_end(args); |
3106 | return ret; | |
3107 | } | |
3108 | ||
3109 | static ssize_t | |
3110 | tracing_mark_write(struct file *filp, const char __user *ubuf, | |
3111 | size_t cnt, loff_t *fpos) | |
3112 | { | |
3113 | char *buf; | |
3114 | char *end; | |
5bf9a1ee | 3115 | |
c76f0694 | 3116 | if (tracing_disabled) |
5bf9a1ee PP |
3117 | return -EINVAL; |
3118 | ||
3119 | if (cnt > TRACE_BUF_SIZE) | |
3120 | cnt = TRACE_BUF_SIZE; | |
3121 | ||
3122 | buf = kmalloc(cnt + 1, GFP_KERNEL); | |
3123 | if (buf == NULL) | |
3124 | return -ENOMEM; | |
3125 | ||
3126 | if (copy_from_user(buf, ubuf, cnt)) { | |
3127 | kfree(buf); | |
3128 | return -EFAULT; | |
3129 | } | |
3130 | ||
3131 | /* Cut from the first nil or newline. */ | |
3132 | buf[cnt] = '\0'; | |
3133 | end = strchr(buf, '\n'); | |
3134 | if (end) | |
3135 | *end = '\0'; | |
3136 | ||
3137 | cnt = mark_printk("%s\n", buf); | |
3138 | kfree(buf); | |
3139 | *fpos += cnt; | |
3140 | ||
3141 | return cnt; | |
3142 | } | |
3143 | ||
5079f326 Z |
3144 | static ssize_t tracing_clock_read(struct file *filp, char __user *ubuf, |
3145 | size_t cnt, loff_t *ppos) | |
3146 | { | |
3147 | char buf[64]; | |
3148 | int bufiter = 0; | |
3149 | int i; | |
3150 | ||
3151 | for (i = 0; i < ARRAY_SIZE(trace_clocks); i++) | |
3152 | bufiter += snprintf(buf + bufiter, sizeof(buf) - bufiter, | |
3153 | "%s%s%s%s", i ? " " : "", | |
3154 | i == trace_clock_id ? "[" : "", trace_clocks[i].name, | |
3155 | i == trace_clock_id ? "]" : ""); | |
3156 | bufiter += snprintf(buf + bufiter, sizeof(buf) - bufiter, "\n"); | |
3157 | ||
3158 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, bufiter); | |
3159 | } | |
3160 | ||
3161 | static ssize_t tracing_clock_write(struct file *filp, const char __user *ubuf, | |
3162 | size_t cnt, loff_t *fpos) | |
3163 | { | |
3164 | char buf[64]; | |
3165 | const char *clockstr; | |
3166 | int i; | |
3167 | ||
3168 | if (cnt >= sizeof(buf)) | |
3169 | return -EINVAL; | |
3170 | ||
3171 | if (copy_from_user(&buf, ubuf, cnt)) | |
3172 | return -EFAULT; | |
3173 | ||
3174 | buf[cnt] = 0; | |
3175 | ||
3176 | clockstr = strstrip(buf); | |
3177 | ||
3178 | for (i = 0; i < ARRAY_SIZE(trace_clocks); i++) { | |
3179 | if (strcmp(trace_clocks[i].name, clockstr) == 0) | |
3180 | break; | |
3181 | } | |
3182 | if (i == ARRAY_SIZE(trace_clocks)) | |
3183 | return -EINVAL; | |
3184 | ||
3185 | trace_clock_id = i; | |
3186 | ||
3187 | mutex_lock(&trace_types_lock); | |
3188 | ||
3189 | ring_buffer_set_clock(global_trace.buffer, trace_clocks[i].func); | |
3190 | if (max_tr.buffer) | |
3191 | ring_buffer_set_clock(max_tr.buffer, trace_clocks[i].func); | |
3192 | ||
3193 | mutex_unlock(&trace_types_lock); | |
3194 | ||
3195 | *fpos += cnt; | |
3196 | ||
3197 | return cnt; | |
3198 | } | |
3199 | ||
5e2336a0 | 3200 | static const struct file_operations tracing_max_lat_fops = { |
4bf39a94 IM |
3201 | .open = tracing_open_generic, |
3202 | .read = tracing_max_lat_read, | |
3203 | .write = tracing_max_lat_write, | |
bc0c38d1 SR |
3204 | }; |
3205 | ||
5e2336a0 | 3206 | static const struct file_operations tracing_ctrl_fops = { |
4bf39a94 IM |
3207 | .open = tracing_open_generic, |
3208 | .read = tracing_ctrl_read, | |
3209 | .write = tracing_ctrl_write, | |
bc0c38d1 SR |
3210 | }; |
3211 | ||
5e2336a0 | 3212 | static const struct file_operations set_tracer_fops = { |
4bf39a94 IM |
3213 | .open = tracing_open_generic, |
3214 | .read = tracing_set_trace_read, | |
3215 | .write = tracing_set_trace_write, | |
bc0c38d1 SR |
3216 | }; |
3217 | ||
5e2336a0 | 3218 | static const struct file_operations tracing_pipe_fops = { |
4bf39a94 | 3219 | .open = tracing_open_pipe, |
2a2cc8f7 | 3220 | .poll = tracing_poll_pipe, |
4bf39a94 | 3221 | .read = tracing_read_pipe, |
3c56819b | 3222 | .splice_read = tracing_splice_read_pipe, |
4bf39a94 | 3223 | .release = tracing_release_pipe, |
b3806b43 SR |
3224 | }; |
3225 | ||
5e2336a0 | 3226 | static const struct file_operations tracing_entries_fops = { |
a98a3c3f SR |
3227 | .open = tracing_open_generic, |
3228 | .read = tracing_entries_read, | |
3229 | .write = tracing_entries_write, | |
3230 | }; | |
3231 | ||
5e2336a0 | 3232 | static const struct file_operations tracing_mark_fops = { |
43a15386 | 3233 | .open = tracing_open_generic, |
5bf9a1ee PP |
3234 | .write = tracing_mark_write, |
3235 | }; | |
3236 | ||
5079f326 Z |
3237 | static const struct file_operations trace_clock_fops = { |
3238 | .open = tracing_open_generic, | |
3239 | .read = tracing_clock_read, | |
3240 | .write = tracing_clock_write, | |
3241 | }; | |
3242 | ||
2cadf913 SR |
3243 | struct ftrace_buffer_info { |
3244 | struct trace_array *tr; | |
3245 | void *spare; | |
3246 | int cpu; | |
3247 | unsigned int read; | |
3248 | }; | |
3249 | ||
3250 | static int tracing_buffers_open(struct inode *inode, struct file *filp) | |
3251 | { | |
3252 | int cpu = (int)(long)inode->i_private; | |
3253 | struct ftrace_buffer_info *info; | |
3254 | ||
3255 | if (tracing_disabled) | |
3256 | return -ENODEV; | |
3257 | ||
3258 | info = kzalloc(sizeof(*info), GFP_KERNEL); | |
3259 | if (!info) | |
3260 | return -ENOMEM; | |
3261 | ||
3262 | info->tr = &global_trace; | |
3263 | info->cpu = cpu; | |
ddd538f3 | 3264 | info->spare = NULL; |
2cadf913 SR |
3265 | /* Force reading ring buffer for first read */ |
3266 | info->read = (unsigned int)-1; | |
2cadf913 SR |
3267 | |
3268 | filp->private_data = info; | |
3269 | ||
d1e7e02f | 3270 | return nonseekable_open(inode, filp); |
2cadf913 SR |
3271 | } |
3272 | ||
3273 | static ssize_t | |
3274 | tracing_buffers_read(struct file *filp, char __user *ubuf, | |
3275 | size_t count, loff_t *ppos) | |
3276 | { | |
3277 | struct ftrace_buffer_info *info = filp->private_data; | |
3278 | unsigned int pos; | |
3279 | ssize_t ret; | |
3280 | size_t size; | |
3281 | ||
2dc5d12b SR |
3282 | if (!count) |
3283 | return 0; | |
3284 | ||
ddd538f3 LJ |
3285 | if (!info->spare) |
3286 | info->spare = ring_buffer_alloc_read_page(info->tr->buffer); | |
3287 | if (!info->spare) | |
3288 | return -ENOMEM; | |
3289 | ||
2cadf913 SR |
3290 | /* Do we have previous read data to read? */ |
3291 | if (info->read < PAGE_SIZE) | |
3292 | goto read; | |
3293 | ||
3294 | info->read = 0; | |
3295 | ||
3296 | ret = ring_buffer_read_page(info->tr->buffer, | |
3297 | &info->spare, | |
3298 | count, | |
3299 | info->cpu, 0); | |
3300 | if (ret < 0) | |
3301 | return 0; | |
3302 | ||
3303 | pos = ring_buffer_page_len(info->spare); | |
3304 | ||
3305 | if (pos < PAGE_SIZE) | |
3306 | memset(info->spare + pos, 0, PAGE_SIZE - pos); | |
3307 | ||
3308 | read: | |
3309 | size = PAGE_SIZE - info->read; | |
3310 | if (size > count) | |
3311 | size = count; | |
3312 | ||
3313 | ret = copy_to_user(ubuf, info->spare + info->read, size); | |
2dc5d12b | 3314 | if (ret == size) |
2cadf913 | 3315 | return -EFAULT; |
2dc5d12b SR |
3316 | size -= ret; |
3317 | ||
2cadf913 SR |
3318 | *ppos += size; |
3319 | info->read += size; | |
3320 | ||
3321 | return size; | |
3322 | } | |
3323 | ||
3324 | static int tracing_buffers_release(struct inode *inode, struct file *file) | |
3325 | { | |
3326 | struct ftrace_buffer_info *info = file->private_data; | |
3327 | ||
ddd538f3 LJ |
3328 | if (info->spare) |
3329 | ring_buffer_free_read_page(info->tr->buffer, info->spare); | |
2cadf913 SR |
3330 | kfree(info); |
3331 | ||
3332 | return 0; | |
3333 | } | |
3334 | ||
3335 | struct buffer_ref { | |
3336 | struct ring_buffer *buffer; | |
3337 | void *page; | |
3338 | int ref; | |
3339 | }; | |
3340 | ||
3341 | static void buffer_pipe_buf_release(struct pipe_inode_info *pipe, | |
3342 | struct pipe_buffer *buf) | |
3343 | { | |
3344 | struct buffer_ref *ref = (struct buffer_ref *)buf->private; | |
3345 | ||
3346 | if (--ref->ref) | |
3347 | return; | |
3348 | ||
3349 | ring_buffer_free_read_page(ref->buffer, ref->page); | |
3350 | kfree(ref); | |
3351 | buf->private = 0; | |
3352 | } | |
3353 | ||
3354 | static int buffer_pipe_buf_steal(struct pipe_inode_info *pipe, | |
3355 | struct pipe_buffer *buf) | |
3356 | { | |
3357 | return 1; | |
3358 | } | |
3359 | ||
3360 | static void buffer_pipe_buf_get(struct pipe_inode_info *pipe, | |
3361 | struct pipe_buffer *buf) | |
3362 | { | |
3363 | struct buffer_ref *ref = (struct buffer_ref *)buf->private; | |
3364 | ||
3365 | ref->ref++; | |
3366 | } | |
3367 | ||
3368 | /* Pipe buffer operations for a buffer. */ | |
3369 | static struct pipe_buf_operations buffer_pipe_buf_ops = { | |
3370 | .can_merge = 0, | |
3371 | .map = generic_pipe_buf_map, | |
3372 | .unmap = generic_pipe_buf_unmap, | |
3373 | .confirm = generic_pipe_buf_confirm, | |
3374 | .release = buffer_pipe_buf_release, | |
3375 | .steal = buffer_pipe_buf_steal, | |
3376 | .get = buffer_pipe_buf_get, | |
3377 | }; | |
3378 | ||
3379 | /* | |
3380 | * Callback from splice_to_pipe(), if we need to release some pages | |
3381 | * at the end of the spd in case we error'ed out in filling the pipe. | |
3382 | */ | |
3383 | static void buffer_spd_release(struct splice_pipe_desc *spd, unsigned int i) | |
3384 | { | |
3385 | struct buffer_ref *ref = | |
3386 | (struct buffer_ref *)spd->partial[i].private; | |
3387 | ||
3388 | if (--ref->ref) | |
3389 | return; | |
3390 | ||
3391 | ring_buffer_free_read_page(ref->buffer, ref->page); | |
3392 | kfree(ref); | |
3393 | spd->partial[i].private = 0; | |
3394 | } | |
3395 | ||
3396 | static ssize_t | |
3397 | tracing_buffers_splice_read(struct file *file, loff_t *ppos, | |
3398 | struct pipe_inode_info *pipe, size_t len, | |
3399 | unsigned int flags) | |
3400 | { | |
3401 | struct ftrace_buffer_info *info = file->private_data; | |
3402 | struct partial_page partial[PIPE_BUFFERS]; | |
3403 | struct page *pages[PIPE_BUFFERS]; | |
3404 | struct splice_pipe_desc spd = { | |
3405 | .pages = pages, | |
3406 | .partial = partial, | |
3407 | .flags = flags, | |
3408 | .ops = &buffer_pipe_buf_ops, | |
3409 | .spd_release = buffer_spd_release, | |
3410 | }; | |
3411 | struct buffer_ref *ref; | |
93459c6c | 3412 | int entries, size, i; |
2cadf913 SR |
3413 | size_t ret; |
3414 | ||
93cfb3c9 LJ |
3415 | if (*ppos & (PAGE_SIZE - 1)) { |
3416 | WARN_ONCE(1, "Ftrace: previous read must page-align\n"); | |
3417 | return -EINVAL; | |
3418 | } | |
3419 | ||
3420 | if (len & (PAGE_SIZE - 1)) { | |
3421 | WARN_ONCE(1, "Ftrace: splice_read should page-align\n"); | |
3422 | if (len < PAGE_SIZE) | |
3423 | return -EINVAL; | |
3424 | len &= PAGE_MASK; | |
3425 | } | |
3426 | ||
93459c6c SR |
3427 | entries = ring_buffer_entries_cpu(info->tr->buffer, info->cpu); |
3428 | ||
3429 | for (i = 0; i < PIPE_BUFFERS && len && entries; i++, len -= PAGE_SIZE) { | |
2cadf913 SR |
3430 | struct page *page; |
3431 | int r; | |
3432 | ||
3433 | ref = kzalloc(sizeof(*ref), GFP_KERNEL); | |
3434 | if (!ref) | |
3435 | break; | |
3436 | ||
7267fa68 | 3437 | ref->ref = 1; |
2cadf913 SR |
3438 | ref->buffer = info->tr->buffer; |
3439 | ref->page = ring_buffer_alloc_read_page(ref->buffer); | |
3440 | if (!ref->page) { | |
3441 | kfree(ref); | |
3442 | break; | |
3443 | } | |
3444 | ||
3445 | r = ring_buffer_read_page(ref->buffer, &ref->page, | |
f2957f1f | 3446 | len, info->cpu, 1); |
2cadf913 SR |
3447 | if (r < 0) { |
3448 | ring_buffer_free_read_page(ref->buffer, | |
3449 | ref->page); | |
3450 | kfree(ref); | |
3451 | break; | |
3452 | } | |
3453 | ||
3454 | /* | |
3455 | * zero out any left over data, this is going to | |
3456 | * user land. | |
3457 | */ | |
3458 | size = ring_buffer_page_len(ref->page); | |
3459 | if (size < PAGE_SIZE) | |
3460 | memset(ref->page + size, 0, PAGE_SIZE - size); | |
3461 | ||
3462 | page = virt_to_page(ref->page); | |
3463 | ||
3464 | spd.pages[i] = page; | |
3465 | spd.partial[i].len = PAGE_SIZE; | |
3466 | spd.partial[i].offset = 0; | |
3467 | spd.partial[i].private = (unsigned long)ref; | |
3468 | spd.nr_pages++; | |
93cfb3c9 | 3469 | *ppos += PAGE_SIZE; |
93459c6c SR |
3470 | |
3471 | entries = ring_buffer_entries_cpu(info->tr->buffer, info->cpu); | |
2cadf913 SR |
3472 | } |
3473 | ||
3474 | spd.nr_pages = i; | |
3475 | ||
3476 | /* did we read anything? */ | |
3477 | if (!spd.nr_pages) { | |
3478 | if (flags & SPLICE_F_NONBLOCK) | |
3479 | ret = -EAGAIN; | |
3480 | else | |
3481 | ret = 0; | |
3482 | /* TODO: block */ | |
3483 | return ret; | |
3484 | } | |
3485 | ||
3486 | ret = splice_to_pipe(pipe, &spd); | |
3487 | ||
3488 | return ret; | |
3489 | } | |
3490 | ||
3491 | static const struct file_operations tracing_buffers_fops = { | |
3492 | .open = tracing_buffers_open, | |
3493 | .read = tracing_buffers_read, | |
3494 | .release = tracing_buffers_release, | |
3495 | .splice_read = tracing_buffers_splice_read, | |
3496 | .llseek = no_llseek, | |
3497 | }; | |
3498 | ||
c8d77183 SR |
3499 | static ssize_t |
3500 | tracing_stats_read(struct file *filp, char __user *ubuf, | |
3501 | size_t count, loff_t *ppos) | |
3502 | { | |
3503 | unsigned long cpu = (unsigned long)filp->private_data; | |
3504 | struct trace_array *tr = &global_trace; | |
3505 | struct trace_seq *s; | |
3506 | unsigned long cnt; | |
3507 | ||
e4f2d10f | 3508 | s = kmalloc(sizeof(*s), GFP_KERNEL); |
c8d77183 SR |
3509 | if (!s) |
3510 | return ENOMEM; | |
3511 | ||
3512 | trace_seq_init(s); | |
3513 | ||
3514 | cnt = ring_buffer_entries_cpu(tr->buffer, cpu); | |
3515 | trace_seq_printf(s, "entries: %ld\n", cnt); | |
3516 | ||
3517 | cnt = ring_buffer_overrun_cpu(tr->buffer, cpu); | |
3518 | trace_seq_printf(s, "overrun: %ld\n", cnt); | |
3519 | ||
3520 | cnt = ring_buffer_commit_overrun_cpu(tr->buffer, cpu); | |
3521 | trace_seq_printf(s, "commit overrun: %ld\n", cnt); | |
3522 | ||
c8d77183 SR |
3523 | count = simple_read_from_buffer(ubuf, count, ppos, s->buffer, s->len); |
3524 | ||
3525 | kfree(s); | |
3526 | ||
3527 | return count; | |
3528 | } | |
3529 | ||
3530 | static const struct file_operations tracing_stats_fops = { | |
3531 | .open = tracing_open_generic, | |
3532 | .read = tracing_stats_read, | |
3533 | }; | |
3534 | ||
bc0c38d1 SR |
3535 | #ifdef CONFIG_DYNAMIC_FTRACE |
3536 | ||
b807c3d0 SR |
3537 | int __weak ftrace_arch_read_dyn_info(char *buf, int size) |
3538 | { | |
3539 | return 0; | |
3540 | } | |
3541 | ||
bc0c38d1 | 3542 | static ssize_t |
b807c3d0 | 3543 | tracing_read_dyn_info(struct file *filp, char __user *ubuf, |
bc0c38d1 SR |
3544 | size_t cnt, loff_t *ppos) |
3545 | { | |
a26a2a27 SR |
3546 | static char ftrace_dyn_info_buffer[1024]; |
3547 | static DEFINE_MUTEX(dyn_info_mutex); | |
bc0c38d1 | 3548 | unsigned long *p = filp->private_data; |
b807c3d0 | 3549 | char *buf = ftrace_dyn_info_buffer; |
a26a2a27 | 3550 | int size = ARRAY_SIZE(ftrace_dyn_info_buffer); |
bc0c38d1 SR |
3551 | int r; |
3552 | ||
b807c3d0 SR |
3553 | mutex_lock(&dyn_info_mutex); |
3554 | r = sprintf(buf, "%ld ", *p); | |
4bf39a94 | 3555 | |
a26a2a27 | 3556 | r += ftrace_arch_read_dyn_info(buf+r, (size-1)-r); |
b807c3d0 SR |
3557 | buf[r++] = '\n'; |
3558 | ||
3559 | r = simple_read_from_buffer(ubuf, cnt, ppos, buf, r); | |
3560 | ||
3561 | mutex_unlock(&dyn_info_mutex); | |
3562 | ||
3563 | return r; | |
bc0c38d1 SR |
3564 | } |
3565 | ||
5e2336a0 | 3566 | static const struct file_operations tracing_dyn_info_fops = { |
4bf39a94 | 3567 | .open = tracing_open_generic, |
b807c3d0 | 3568 | .read = tracing_read_dyn_info, |
bc0c38d1 SR |
3569 | }; |
3570 | #endif | |
3571 | ||
3572 | static struct dentry *d_tracer; | |
3573 | ||
3574 | struct dentry *tracing_init_dentry(void) | |
3575 | { | |
3576 | static int once; | |
3577 | ||
3578 | if (d_tracer) | |
3579 | return d_tracer; | |
3580 | ||
3e1f60b8 FW |
3581 | if (!debugfs_initialized()) |
3582 | return NULL; | |
3583 | ||
bc0c38d1 SR |
3584 | d_tracer = debugfs_create_dir("tracing", NULL); |
3585 | ||
3586 | if (!d_tracer && !once) { | |
3587 | once = 1; | |
3588 | pr_warning("Could not create debugfs directory 'tracing'\n"); | |
3589 | return NULL; | |
3590 | } | |
3591 | ||
3592 | return d_tracer; | |
3593 | } | |
3594 | ||
b04cc6b1 FW |
3595 | static struct dentry *d_percpu; |
3596 | ||
3597 | struct dentry *tracing_dentry_percpu(void) | |
3598 | { | |
3599 | static int once; | |
3600 | struct dentry *d_tracer; | |
3601 | ||
3602 | if (d_percpu) | |
3603 | return d_percpu; | |
3604 | ||
3605 | d_tracer = tracing_init_dentry(); | |
3606 | ||
3607 | if (!d_tracer) | |
3608 | return NULL; | |
3609 | ||
3610 | d_percpu = debugfs_create_dir("per_cpu", d_tracer); | |
3611 | ||
3612 | if (!d_percpu && !once) { | |
3613 | once = 1; | |
3614 | pr_warning("Could not create debugfs directory 'per_cpu'\n"); | |
3615 | return NULL; | |
3616 | } | |
3617 | ||
3618 | return d_percpu; | |
3619 | } | |
3620 | ||
3621 | static void tracing_init_debugfs_percpu(long cpu) | |
3622 | { | |
3623 | struct dentry *d_percpu = tracing_dentry_percpu(); | |
5452af66 | 3624 | struct dentry *d_cpu; |
8656e7a2 FW |
3625 | /* strlen(cpu) + MAX(log10(cpu)) + '\0' */ |
3626 | char cpu_dir[7]; | |
b04cc6b1 FW |
3627 | |
3628 | if (cpu > 999 || cpu < 0) | |
3629 | return; | |
3630 | ||
8656e7a2 FW |
3631 | sprintf(cpu_dir, "cpu%ld", cpu); |
3632 | d_cpu = debugfs_create_dir(cpu_dir, d_percpu); | |
3633 | if (!d_cpu) { | |
3634 | pr_warning("Could not create debugfs '%s' entry\n", cpu_dir); | |
3635 | return; | |
3636 | } | |
b04cc6b1 | 3637 | |
8656e7a2 | 3638 | /* per cpu trace_pipe */ |
5452af66 FW |
3639 | trace_create_file("trace_pipe", 0444, d_cpu, |
3640 | (void *) cpu, &tracing_pipe_fops); | |
b04cc6b1 FW |
3641 | |
3642 | /* per cpu trace */ | |
5452af66 FW |
3643 | trace_create_file("trace", 0644, d_cpu, |
3644 | (void *) cpu, &tracing_fops); | |
7f96f93f | 3645 | |
5452af66 FW |
3646 | trace_create_file("trace_pipe_raw", 0444, d_cpu, |
3647 | (void *) cpu, &tracing_buffers_fops); | |
7f96f93f | 3648 | |
c8d77183 SR |
3649 | trace_create_file("stats", 0444, d_cpu, |
3650 | (void *) cpu, &tracing_stats_fops); | |
b04cc6b1 FW |
3651 | } |
3652 | ||
60a11774 SR |
3653 | #ifdef CONFIG_FTRACE_SELFTEST |
3654 | /* Let selftest have access to static functions in this file */ | |
3655 | #include "trace_selftest.c" | |
3656 | #endif | |
3657 | ||
577b785f SR |
3658 | struct trace_option_dentry { |
3659 | struct tracer_opt *opt; | |
3660 | struct tracer_flags *flags; | |
3661 | struct dentry *entry; | |
3662 | }; | |
3663 | ||
3664 | static ssize_t | |
3665 | trace_options_read(struct file *filp, char __user *ubuf, size_t cnt, | |
3666 | loff_t *ppos) | |
3667 | { | |
3668 | struct trace_option_dentry *topt = filp->private_data; | |
3669 | char *buf; | |
3670 | ||
3671 | if (topt->flags->val & topt->opt->bit) | |
3672 | buf = "1\n"; | |
3673 | else | |
3674 | buf = "0\n"; | |
3675 | ||
3676 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, 2); | |
3677 | } | |
3678 | ||
3679 | static ssize_t | |
3680 | trace_options_write(struct file *filp, const char __user *ubuf, size_t cnt, | |
3681 | loff_t *ppos) | |
3682 | { | |
3683 | struct trace_option_dentry *topt = filp->private_data; | |
3684 | unsigned long val; | |
3685 | char buf[64]; | |
3686 | int ret; | |
3687 | ||
3688 | if (cnt >= sizeof(buf)) | |
3689 | return -EINVAL; | |
3690 | ||
3691 | if (copy_from_user(&buf, ubuf, cnt)) | |
3692 | return -EFAULT; | |
3693 | ||
3694 | buf[cnt] = 0; | |
3695 | ||
3696 | ret = strict_strtoul(buf, 10, &val); | |
3697 | if (ret < 0) | |
3698 | return ret; | |
3699 | ||
3700 | ret = 0; | |
3701 | switch (val) { | |
3702 | case 0: | |
3703 | /* do nothing if already cleared */ | |
3704 | if (!(topt->flags->val & topt->opt->bit)) | |
3705 | break; | |
3706 | ||
3707 | mutex_lock(&trace_types_lock); | |
3708 | if (current_trace->set_flag) | |
3709 | ret = current_trace->set_flag(topt->flags->val, | |
3710 | topt->opt->bit, 0); | |
3711 | mutex_unlock(&trace_types_lock); | |
3712 | if (ret) | |
3713 | return ret; | |
3714 | topt->flags->val &= ~topt->opt->bit; | |
3715 | break; | |
3716 | case 1: | |
3717 | /* do nothing if already set */ | |
3718 | if (topt->flags->val & topt->opt->bit) | |
3719 | break; | |
3720 | ||
3721 | mutex_lock(&trace_types_lock); | |
3722 | if (current_trace->set_flag) | |
3723 | ret = current_trace->set_flag(topt->flags->val, | |
3724 | topt->opt->bit, 1); | |
3725 | mutex_unlock(&trace_types_lock); | |
3726 | if (ret) | |
3727 | return ret; | |
3728 | topt->flags->val |= topt->opt->bit; | |
3729 | break; | |
3730 | ||
3731 | default: | |
3732 | return -EINVAL; | |
3733 | } | |
3734 | ||
3735 | *ppos += cnt; | |
3736 | ||
3737 | return cnt; | |
3738 | } | |
3739 | ||
3740 | ||
3741 | static const struct file_operations trace_options_fops = { | |
3742 | .open = tracing_open_generic, | |
3743 | .read = trace_options_read, | |
3744 | .write = trace_options_write, | |
3745 | }; | |
3746 | ||
a8259075 SR |
3747 | static ssize_t |
3748 | trace_options_core_read(struct file *filp, char __user *ubuf, size_t cnt, | |
3749 | loff_t *ppos) | |
3750 | { | |
3751 | long index = (long)filp->private_data; | |
3752 | char *buf; | |
3753 | ||
3754 | if (trace_flags & (1 << index)) | |
3755 | buf = "1\n"; | |
3756 | else | |
3757 | buf = "0\n"; | |
3758 | ||
3759 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, 2); | |
3760 | } | |
3761 | ||
3762 | static ssize_t | |
3763 | trace_options_core_write(struct file *filp, const char __user *ubuf, size_t cnt, | |
3764 | loff_t *ppos) | |
3765 | { | |
3766 | long index = (long)filp->private_data; | |
3767 | char buf[64]; | |
3768 | unsigned long val; | |
3769 | int ret; | |
3770 | ||
3771 | if (cnt >= sizeof(buf)) | |
3772 | return -EINVAL; | |
3773 | ||
3774 | if (copy_from_user(&buf, ubuf, cnt)) | |
3775 | return -EFAULT; | |
3776 | ||
3777 | buf[cnt] = 0; | |
3778 | ||
3779 | ret = strict_strtoul(buf, 10, &val); | |
3780 | if (ret < 0) | |
3781 | return ret; | |
3782 | ||
3783 | switch (val) { | |
3784 | case 0: | |
3785 | trace_flags &= ~(1 << index); | |
3786 | break; | |
3787 | case 1: | |
3788 | trace_flags |= 1 << index; | |
3789 | break; | |
3790 | ||
3791 | default: | |
3792 | return -EINVAL; | |
3793 | } | |
3794 | ||
3795 | *ppos += cnt; | |
3796 | ||
3797 | return cnt; | |
3798 | } | |
3799 | ||
a8259075 SR |
3800 | static const struct file_operations trace_options_core_fops = { |
3801 | .open = tracing_open_generic, | |
3802 | .read = trace_options_core_read, | |
3803 | .write = trace_options_core_write, | |
3804 | }; | |
3805 | ||
5452af66 FW |
3806 | struct dentry *trace_create_file(const char *name, |
3807 | mode_t mode, | |
3808 | struct dentry *parent, | |
3809 | void *data, | |
3810 | const struct file_operations *fops) | |
3811 | { | |
3812 | struct dentry *ret; | |
3813 | ||
3814 | ret = debugfs_create_file(name, mode, parent, data, fops); | |
3815 | if (!ret) | |
3816 | pr_warning("Could not create debugfs '%s' entry\n", name); | |
3817 | ||
3818 | return ret; | |
3819 | } | |
3820 | ||
3821 | ||
a8259075 SR |
3822 | static struct dentry *trace_options_init_dentry(void) |
3823 | { | |
3824 | struct dentry *d_tracer; | |
3825 | static struct dentry *t_options; | |
3826 | ||
3827 | if (t_options) | |
3828 | return t_options; | |
3829 | ||
3830 | d_tracer = tracing_init_dentry(); | |
3831 | if (!d_tracer) | |
3832 | return NULL; | |
3833 | ||
3834 | t_options = debugfs_create_dir("options", d_tracer); | |
3835 | if (!t_options) { | |
3836 | pr_warning("Could not create debugfs directory 'options'\n"); | |
3837 | return NULL; | |
3838 | } | |
3839 | ||
3840 | return t_options; | |
3841 | } | |
3842 | ||
577b785f SR |
3843 | static void |
3844 | create_trace_option_file(struct trace_option_dentry *topt, | |
3845 | struct tracer_flags *flags, | |
3846 | struct tracer_opt *opt) | |
3847 | { | |
3848 | struct dentry *t_options; | |
577b785f SR |
3849 | |
3850 | t_options = trace_options_init_dentry(); | |
3851 | if (!t_options) | |
3852 | return; | |
3853 | ||
3854 | topt->flags = flags; | |
3855 | topt->opt = opt; | |
3856 | ||
5452af66 | 3857 | topt->entry = trace_create_file(opt->name, 0644, t_options, topt, |
577b785f SR |
3858 | &trace_options_fops); |
3859 | ||
577b785f SR |
3860 | } |
3861 | ||
3862 | static struct trace_option_dentry * | |
3863 | create_trace_option_files(struct tracer *tracer) | |
3864 | { | |
3865 | struct trace_option_dentry *topts; | |
3866 | struct tracer_flags *flags; | |
3867 | struct tracer_opt *opts; | |
3868 | int cnt; | |
3869 | ||
3870 | if (!tracer) | |
3871 | return NULL; | |
3872 | ||
3873 | flags = tracer->flags; | |
3874 | ||
3875 | if (!flags || !flags->opts) | |
3876 | return NULL; | |
3877 | ||
3878 | opts = flags->opts; | |
3879 | ||
3880 | for (cnt = 0; opts[cnt].name; cnt++) | |
3881 | ; | |
3882 | ||
0cfe8245 | 3883 | topts = kcalloc(cnt + 1, sizeof(*topts), GFP_KERNEL); |
577b785f SR |
3884 | if (!topts) |
3885 | return NULL; | |
3886 | ||
3887 | for (cnt = 0; opts[cnt].name; cnt++) | |
3888 | create_trace_option_file(&topts[cnt], flags, | |
3889 | &opts[cnt]); | |
3890 | ||
3891 | return topts; | |
3892 | } | |
3893 | ||
3894 | static void | |
3895 | destroy_trace_option_files(struct trace_option_dentry *topts) | |
3896 | { | |
3897 | int cnt; | |
3898 | ||
3899 | if (!topts) | |
3900 | return; | |
3901 | ||
3902 | for (cnt = 0; topts[cnt].opt; cnt++) { | |
3903 | if (topts[cnt].entry) | |
3904 | debugfs_remove(topts[cnt].entry); | |
3905 | } | |
3906 | ||
3907 | kfree(topts); | |
3908 | } | |
3909 | ||
a8259075 SR |
3910 | static struct dentry * |
3911 | create_trace_option_core_file(const char *option, long index) | |
3912 | { | |
3913 | struct dentry *t_options; | |
a8259075 SR |
3914 | |
3915 | t_options = trace_options_init_dentry(); | |
3916 | if (!t_options) | |
3917 | return NULL; | |
3918 | ||
5452af66 | 3919 | return trace_create_file(option, 0644, t_options, (void *)index, |
a8259075 | 3920 | &trace_options_core_fops); |
a8259075 SR |
3921 | } |
3922 | ||
3923 | static __init void create_trace_options_dir(void) | |
3924 | { | |
3925 | struct dentry *t_options; | |
a8259075 SR |
3926 | int i; |
3927 | ||
3928 | t_options = trace_options_init_dentry(); | |
3929 | if (!t_options) | |
3930 | return; | |
3931 | ||
5452af66 FW |
3932 | for (i = 0; trace_options[i]; i++) |
3933 | create_trace_option_core_file(trace_options[i], i); | |
a8259075 SR |
3934 | } |
3935 | ||
b5ad384e | 3936 | static __init int tracer_init_debugfs(void) |
bc0c38d1 SR |
3937 | { |
3938 | struct dentry *d_tracer; | |
b04cc6b1 | 3939 | int cpu; |
bc0c38d1 SR |
3940 | |
3941 | d_tracer = tracing_init_dentry(); | |
3942 | ||
5452af66 FW |
3943 | trace_create_file("tracing_enabled", 0644, d_tracer, |
3944 | &global_trace, &tracing_ctrl_fops); | |
bc0c38d1 | 3945 | |
5452af66 FW |
3946 | trace_create_file("trace_options", 0644, d_tracer, |
3947 | NULL, &tracing_iter_fops); | |
bc0c38d1 | 3948 | |
5452af66 FW |
3949 | trace_create_file("tracing_cpumask", 0644, d_tracer, |
3950 | NULL, &tracing_cpumask_fops); | |
3951 | ||
3952 | trace_create_file("trace", 0644, d_tracer, | |
3953 | (void *) TRACE_PIPE_ALL_CPU, &tracing_fops); | |
a8259075 | 3954 | |
5452af66 FW |
3955 | trace_create_file("available_tracers", 0444, d_tracer, |
3956 | &global_trace, &show_traces_fops); | |
3957 | ||
339ae5d3 | 3958 | trace_create_file("current_tracer", 0644, d_tracer, |
5452af66 FW |
3959 | &global_trace, &set_tracer_fops); |
3960 | ||
5d4a9dba | 3961 | #ifdef CONFIG_TRACER_MAX_TRACE |
5452af66 FW |
3962 | trace_create_file("tracing_max_latency", 0644, d_tracer, |
3963 | &tracing_max_latency, &tracing_max_lat_fops); | |
3964 | ||
3965 | trace_create_file("tracing_thresh", 0644, d_tracer, | |
3966 | &tracing_thresh, &tracing_max_lat_fops); | |
5d4a9dba | 3967 | #endif |
a8259075 | 3968 | |
339ae5d3 | 3969 | trace_create_file("README", 0444, d_tracer, |
5452af66 FW |
3970 | NULL, &tracing_readme_fops); |
3971 | ||
3972 | trace_create_file("trace_pipe", 0444, d_tracer, | |
b04cc6b1 | 3973 | (void *) TRACE_PIPE_ALL_CPU, &tracing_pipe_fops); |
5452af66 FW |
3974 | |
3975 | trace_create_file("buffer_size_kb", 0644, d_tracer, | |
3976 | &global_trace, &tracing_entries_fops); | |
3977 | ||
3978 | trace_create_file("trace_marker", 0220, d_tracer, | |
3979 | NULL, &tracing_mark_fops); | |
5bf9a1ee | 3980 | |
69abe6a5 AP |
3981 | trace_create_file("saved_cmdlines", 0444, d_tracer, |
3982 | NULL, &tracing_saved_cmdlines_fops); | |
5bf9a1ee | 3983 | |
5079f326 Z |
3984 | trace_create_file("trace_clock", 0644, d_tracer, NULL, |
3985 | &trace_clock_fops); | |
3986 | ||
bc0c38d1 | 3987 | #ifdef CONFIG_DYNAMIC_FTRACE |
5452af66 FW |
3988 | trace_create_file("dyn_ftrace_total_info", 0444, d_tracer, |
3989 | &ftrace_update_tot_cnt, &tracing_dyn_info_fops); | |
bc0c38d1 | 3990 | #endif |
d618b3e6 IM |
3991 | #ifdef CONFIG_SYSPROF_TRACER |
3992 | init_tracer_sysprof_debugfs(d_tracer); | |
3993 | #endif | |
b04cc6b1 | 3994 | |
5452af66 FW |
3995 | create_trace_options_dir(); |
3996 | ||
b04cc6b1 FW |
3997 | for_each_tracing_cpu(cpu) |
3998 | tracing_init_debugfs_percpu(cpu); | |
3999 | ||
b5ad384e | 4000 | return 0; |
bc0c38d1 SR |
4001 | } |
4002 | ||
3f5a54e3 SR |
4003 | static int trace_panic_handler(struct notifier_block *this, |
4004 | unsigned long event, void *unused) | |
4005 | { | |
944ac425 SR |
4006 | if (ftrace_dump_on_oops) |
4007 | ftrace_dump(); | |
3f5a54e3 SR |
4008 | return NOTIFY_OK; |
4009 | } | |
4010 | ||
4011 | static struct notifier_block trace_panic_notifier = { | |
4012 | .notifier_call = trace_panic_handler, | |
4013 | .next = NULL, | |
4014 | .priority = 150 /* priority: INT_MAX >= x >= 0 */ | |
4015 | }; | |
4016 | ||
4017 | static int trace_die_handler(struct notifier_block *self, | |
4018 | unsigned long val, | |
4019 | void *data) | |
4020 | { | |
4021 | switch (val) { | |
4022 | case DIE_OOPS: | |
944ac425 SR |
4023 | if (ftrace_dump_on_oops) |
4024 | ftrace_dump(); | |
3f5a54e3 SR |
4025 | break; |
4026 | default: | |
4027 | break; | |
4028 | } | |
4029 | return NOTIFY_OK; | |
4030 | } | |
4031 | ||
4032 | static struct notifier_block trace_die_notifier = { | |
4033 | .notifier_call = trace_die_handler, | |
4034 | .priority = 200 | |
4035 | }; | |
4036 | ||
4037 | /* | |
4038 | * printk is set to max of 1024, we really don't need it that big. | |
4039 | * Nothing should be printing 1000 characters anyway. | |
4040 | */ | |
4041 | #define TRACE_MAX_PRINT 1000 | |
4042 | ||
4043 | /* | |
4044 | * Define here KERN_TRACE so that we have one place to modify | |
4045 | * it if we decide to change what log level the ftrace dump | |
4046 | * should be at. | |
4047 | */ | |
428aee14 | 4048 | #define KERN_TRACE KERN_EMERG |
3f5a54e3 SR |
4049 | |
4050 | static void | |
4051 | trace_printk_seq(struct trace_seq *s) | |
4052 | { | |
4053 | /* Probably should print a warning here. */ | |
4054 | if (s->len >= 1000) | |
4055 | s->len = 1000; | |
4056 | ||
4057 | /* should be zero ended, but we are paranoid. */ | |
4058 | s->buffer[s->len] = 0; | |
4059 | ||
4060 | printk(KERN_TRACE "%s", s->buffer); | |
4061 | ||
f9520750 | 4062 | trace_seq_init(s); |
3f5a54e3 SR |
4063 | } |
4064 | ||
cf586b61 | 4065 | static void __ftrace_dump(bool disable_tracing) |
3f5a54e3 | 4066 | { |
cd891ae0 SR |
4067 | static raw_spinlock_t ftrace_dump_lock = |
4068 | (raw_spinlock_t)__RAW_SPIN_LOCK_UNLOCKED; | |
3f5a54e3 SR |
4069 | /* use static because iter can be a bit big for the stack */ |
4070 | static struct trace_iterator iter; | |
cf586b61 | 4071 | unsigned int old_userobj; |
3f5a54e3 | 4072 | static int dump_ran; |
d769041f SR |
4073 | unsigned long flags; |
4074 | int cnt = 0, cpu; | |
3f5a54e3 SR |
4075 | |
4076 | /* only one dump */ | |
cd891ae0 SR |
4077 | local_irq_save(flags); |
4078 | __raw_spin_lock(&ftrace_dump_lock); | |
3f5a54e3 SR |
4079 | if (dump_ran) |
4080 | goto out; | |
4081 | ||
4082 | dump_ran = 1; | |
4083 | ||
0ee6b6cf | 4084 | tracing_off(); |
cf586b61 FW |
4085 | |
4086 | if (disable_tracing) | |
4087 | ftrace_kill(); | |
3f5a54e3 | 4088 | |
d769041f SR |
4089 | for_each_tracing_cpu(cpu) { |
4090 | atomic_inc(&global_trace.data[cpu]->disabled); | |
4091 | } | |
4092 | ||
cf586b61 FW |
4093 | old_userobj = trace_flags & TRACE_ITER_SYM_USEROBJ; |
4094 | ||
b54d3de9 TE |
4095 | /* don't look at user memory in panic mode */ |
4096 | trace_flags &= ~TRACE_ITER_SYM_USEROBJ; | |
4097 | ||
3f5a54e3 SR |
4098 | printk(KERN_TRACE "Dumping ftrace buffer:\n"); |
4099 | ||
e543ad76 | 4100 | /* Simulate the iterator */ |
3f5a54e3 SR |
4101 | iter.tr = &global_trace; |
4102 | iter.trace = current_trace; | |
e543ad76 | 4103 | iter.cpu_file = TRACE_PIPE_ALL_CPU; |
3f5a54e3 SR |
4104 | |
4105 | /* | |
4106 | * We need to stop all tracing on all CPUS to read the | |
4107 | * the next buffer. This is a bit expensive, but is | |
4108 | * not done often. We fill all what we can read, | |
4109 | * and then release the locks again. | |
4110 | */ | |
4111 | ||
3f5a54e3 SR |
4112 | while (!trace_empty(&iter)) { |
4113 | ||
4114 | if (!cnt) | |
4115 | printk(KERN_TRACE "---------------------------------\n"); | |
4116 | ||
4117 | cnt++; | |
4118 | ||
4119 | /* reset all but tr, trace, and overruns */ | |
4120 | memset(&iter.seq, 0, | |
4121 | sizeof(struct trace_iterator) - | |
4122 | offsetof(struct trace_iterator, seq)); | |
4123 | iter.iter_flags |= TRACE_FILE_LAT_FMT; | |
4124 | iter.pos = -1; | |
4125 | ||
4126 | if (find_next_entry_inc(&iter) != NULL) { | |
74e7ff8c LJ |
4127 | int ret; |
4128 | ||
4129 | ret = print_trace_line(&iter); | |
4130 | if (ret != TRACE_TYPE_NO_CONSUME) | |
4131 | trace_consume(&iter); | |
3f5a54e3 SR |
4132 | } |
4133 | ||
4134 | trace_printk_seq(&iter.seq); | |
4135 | } | |
4136 | ||
4137 | if (!cnt) | |
4138 | printk(KERN_TRACE " (ftrace buffer empty)\n"); | |
4139 | else | |
4140 | printk(KERN_TRACE "---------------------------------\n"); | |
4141 | ||
cf586b61 FW |
4142 | /* Re-enable tracing if requested */ |
4143 | if (!disable_tracing) { | |
4144 | trace_flags |= old_userobj; | |
4145 | ||
4146 | for_each_tracing_cpu(cpu) { | |
4147 | atomic_dec(&global_trace.data[cpu]->disabled); | |
4148 | } | |
4149 | tracing_on(); | |
4150 | } | |
4151 | ||
3f5a54e3 | 4152 | out: |
cd891ae0 SR |
4153 | __raw_spin_unlock(&ftrace_dump_lock); |
4154 | local_irq_restore(flags); | |
3f5a54e3 SR |
4155 | } |
4156 | ||
cf586b61 FW |
4157 | /* By default: disable tracing after the dump */ |
4158 | void ftrace_dump(void) | |
4159 | { | |
4160 | __ftrace_dump(true); | |
4161 | } | |
4162 | ||
3928a8a2 | 4163 | __init static int tracer_alloc_buffers(void) |
bc0c38d1 | 4164 | { |
73c5162a | 4165 | int ring_buf_size; |
4c11d7ae | 4166 | int i; |
9e01c1b7 | 4167 | int ret = -ENOMEM; |
4c11d7ae | 4168 | |
9e01c1b7 RR |
4169 | if (!alloc_cpumask_var(&tracing_buffer_mask, GFP_KERNEL)) |
4170 | goto out; | |
4171 | ||
4172 | if (!alloc_cpumask_var(&tracing_cpumask, GFP_KERNEL)) | |
4173 | goto out_free_buffer_mask; | |
4c11d7ae | 4174 | |
b04cc6b1 FW |
4175 | if (!alloc_cpumask_var(&tracing_reader_cpumask, GFP_KERNEL)) |
4176 | goto out_free_tracing_cpumask; | |
4177 | ||
73c5162a SR |
4178 | /* To save memory, keep the ring buffer size to its minimum */ |
4179 | if (ring_buffer_expanded) | |
4180 | ring_buf_size = trace_buf_size; | |
4181 | else | |
4182 | ring_buf_size = 1; | |
4183 | ||
9e01c1b7 RR |
4184 | cpumask_copy(tracing_buffer_mask, cpu_possible_mask); |
4185 | cpumask_copy(tracing_cpumask, cpu_all_mask); | |
b04cc6b1 | 4186 | cpumask_clear(tracing_reader_cpumask); |
9e01c1b7 RR |
4187 | |
4188 | /* TODO: make the number of buffers hot pluggable with CPUS */ | |
73c5162a | 4189 | global_trace.buffer = ring_buffer_alloc(ring_buf_size, |
3928a8a2 SR |
4190 | TRACE_BUFFER_FLAGS); |
4191 | if (!global_trace.buffer) { | |
4192 | printk(KERN_ERR "tracer: failed to allocate ring buffer!\n"); | |
4193 | WARN_ON(1); | |
9e01c1b7 | 4194 | goto out_free_cpumask; |
4c11d7ae | 4195 | } |
3928a8a2 | 4196 | global_trace.entries = ring_buffer_size(global_trace.buffer); |
4c11d7ae | 4197 | |
9e01c1b7 | 4198 | |
4c11d7ae | 4199 | #ifdef CONFIG_TRACER_MAX_TRACE |
73c5162a | 4200 | max_tr.buffer = ring_buffer_alloc(ring_buf_size, |
3928a8a2 SR |
4201 | TRACE_BUFFER_FLAGS); |
4202 | if (!max_tr.buffer) { | |
4203 | printk(KERN_ERR "tracer: failed to allocate max ring buffer!\n"); | |
4204 | WARN_ON(1); | |
4205 | ring_buffer_free(global_trace.buffer); | |
9e01c1b7 | 4206 | goto out_free_cpumask; |
4c11d7ae | 4207 | } |
3928a8a2 SR |
4208 | max_tr.entries = ring_buffer_size(max_tr.buffer); |
4209 | WARN_ON(max_tr.entries != global_trace.entries); | |
a98a3c3f | 4210 | #endif |
ab46428c | 4211 | |
4c11d7ae | 4212 | /* Allocate the first page for all buffers */ |
ab46428c | 4213 | for_each_tracing_cpu(i) { |
566b0aaf | 4214 | global_trace.data[i] = &per_cpu(global_trace_cpu, i); |
bc0c38d1 | 4215 | max_tr.data[i] = &per_cpu(max_data, i); |
4c11d7ae | 4216 | } |
bc0c38d1 | 4217 | |
bc0c38d1 SR |
4218 | trace_init_cmdlines(); |
4219 | ||
43a15386 | 4220 | register_tracer(&nop_trace); |
79fb0768 | 4221 | current_trace = &nop_trace; |
b5ad384e FW |
4222 | #ifdef CONFIG_BOOT_TRACER |
4223 | register_tracer(&boot_tracer); | |
b5ad384e | 4224 | #endif |
60a11774 SR |
4225 | /* All seems OK, enable tracing */ |
4226 | tracing_disabled = 0; | |
3928a8a2 | 4227 | |
3f5a54e3 SR |
4228 | atomic_notifier_chain_register(&panic_notifier_list, |
4229 | &trace_panic_notifier); | |
4230 | ||
4231 | register_die_notifier(&trace_die_notifier); | |
2fc1dfbe FW |
4232 | |
4233 | return 0; | |
3f5a54e3 | 4234 | |
9e01c1b7 | 4235 | out_free_cpumask: |
b04cc6b1 FW |
4236 | free_cpumask_var(tracing_reader_cpumask); |
4237 | out_free_tracing_cpumask: | |
9e01c1b7 RR |
4238 | free_cpumask_var(tracing_cpumask); |
4239 | out_free_buffer_mask: | |
4240 | free_cpumask_var(tracing_buffer_mask); | |
4241 | out: | |
4242 | return ret; | |
bc0c38d1 | 4243 | } |
b2821ae6 SR |
4244 | |
4245 | __init static int clear_boot_tracer(void) | |
4246 | { | |
4247 | /* | |
4248 | * The default tracer at boot buffer is an init section. | |
4249 | * This function is called in lateinit. If we did not | |
4250 | * find the boot tracer, then clear it out, to prevent | |
4251 | * later registration from accessing the buffer that is | |
4252 | * about to be freed. | |
4253 | */ | |
4254 | if (!default_bootup_tracer) | |
4255 | return 0; | |
4256 | ||
4257 | printk(KERN_INFO "ftrace bootup tracer '%s' not registered.\n", | |
4258 | default_bootup_tracer); | |
4259 | default_bootup_tracer = NULL; | |
4260 | ||
4261 | return 0; | |
4262 | } | |
4263 | ||
b5ad384e FW |
4264 | early_initcall(tracer_alloc_buffers); |
4265 | fs_initcall(tracer_init_debugfs); | |
b2821ae6 | 4266 | late_initcall(clear_boot_tracer); |