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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 | ||
745b1626 | 46 | unsigned long __read_mostly tracing_max_latency; |
bc0c38d1 SR |
47 | unsigned long __read_mostly tracing_thresh; |
48 | ||
73c5162a SR |
49 | /* |
50 | * On boot up, the ring buffer is set to the minimum size, so that | |
51 | * we do not waste memory on systems that are not using tracing. | |
52 | */ | |
020e5f85 | 53 | int ring_buffer_expanded; |
73c5162a | 54 | |
8e1b82e0 FW |
55 | /* |
56 | * We need to change this state when a selftest is running. | |
ff32504f FW |
57 | * A selftest will lurk into the ring-buffer to count the |
58 | * entries inserted during the selftest although some concurrent | |
5e1607a0 | 59 | * insertions into the ring-buffer such as trace_printk could occurred |
ff32504f FW |
60 | * at the same time, giving false positive or negative results. |
61 | */ | |
8e1b82e0 | 62 | static bool __read_mostly tracing_selftest_running; |
ff32504f | 63 | |
b2821ae6 SR |
64 | /* |
65 | * If a tracer is running, we do not want to run SELFTEST. | |
66 | */ | |
020e5f85 | 67 | bool __read_mostly tracing_selftest_disabled; |
b2821ae6 | 68 | |
adf9f195 FW |
69 | /* For tracers that don't implement custom flags */ |
70 | static struct tracer_opt dummy_tracer_opt[] = { | |
71 | { } | |
72 | }; | |
73 | ||
74 | static struct tracer_flags dummy_tracer_flags = { | |
75 | .val = 0, | |
76 | .opts = dummy_tracer_opt | |
77 | }; | |
78 | ||
79 | static int dummy_set_flag(u32 old_flags, u32 bit, int set) | |
80 | { | |
81 | return 0; | |
82 | } | |
0f048701 SR |
83 | |
84 | /* | |
85 | * Kill all tracing for good (never come back). | |
86 | * It is initialized to 1 but will turn to zero if the initialization | |
87 | * of the tracer is successful. But that is the only place that sets | |
88 | * this back to zero. | |
89 | */ | |
4fd27358 | 90 | static int tracing_disabled = 1; |
0f048701 | 91 | |
5e5bf483 | 92 | DEFINE_PER_CPU(local_t, ftrace_cpu_disabled); |
d769041f SR |
93 | |
94 | static inline void ftrace_disable_cpu(void) | |
95 | { | |
96 | preempt_disable(); | |
97 | local_inc(&__get_cpu_var(ftrace_cpu_disabled)); | |
98 | } | |
99 | ||
100 | static inline void ftrace_enable_cpu(void) | |
101 | { | |
102 | local_dec(&__get_cpu_var(ftrace_cpu_disabled)); | |
103 | preempt_enable(); | |
104 | } | |
105 | ||
9e01c1b7 | 106 | static cpumask_var_t __read_mostly tracing_buffer_mask; |
ab46428c | 107 | |
b04cc6b1 FW |
108 | /* Define which cpu buffers are currently read in trace_pipe */ |
109 | static cpumask_var_t tracing_reader_cpumask; | |
110 | ||
ab46428c | 111 | #define for_each_tracing_cpu(cpu) \ |
9e01c1b7 | 112 | for_each_cpu(cpu, tracing_buffer_mask) |
ab46428c | 113 | |
944ac425 SR |
114 | /* |
115 | * ftrace_dump_on_oops - variable to dump ftrace buffer on oops | |
116 | * | |
117 | * If there is an oops (or kernel panic) and the ftrace_dump_on_oops | |
118 | * is set, then ftrace_dump is called. This will output the contents | |
119 | * of the ftrace buffers to the console. This is very useful for | |
120 | * capturing traces that lead to crashes and outputing it to a | |
121 | * serial console. | |
122 | * | |
123 | * It is default off, but you can enable it with either specifying | |
124 | * "ftrace_dump_on_oops" in the kernel command line, or setting | |
125 | * /proc/sys/kernel/ftrace_dump_on_oops to true. | |
126 | */ | |
127 | int ftrace_dump_on_oops; | |
128 | ||
b2821ae6 SR |
129 | static int tracing_set_tracer(const char *buf); |
130 | ||
131 | #define BOOTUP_TRACER_SIZE 100 | |
132 | static char bootup_tracer_buf[BOOTUP_TRACER_SIZE] __initdata; | |
133 | static char *default_bootup_tracer; | |
d9e54076 PZ |
134 | |
135 | static int __init set_ftrace(char *str) | |
136 | { | |
b2821ae6 SR |
137 | strncpy(bootup_tracer_buf, str, BOOTUP_TRACER_SIZE); |
138 | default_bootup_tracer = bootup_tracer_buf; | |
73c5162a SR |
139 | /* We are using ftrace early, expand it */ |
140 | ring_buffer_expanded = 1; | |
d9e54076 PZ |
141 | return 1; |
142 | } | |
b2821ae6 | 143 | __setup("ftrace=", set_ftrace); |
d9e54076 | 144 | |
944ac425 SR |
145 | static int __init set_ftrace_dump_on_oops(char *str) |
146 | { | |
147 | ftrace_dump_on_oops = 1; | |
148 | return 1; | |
149 | } | |
150 | __setup("ftrace_dump_on_oops", set_ftrace_dump_on_oops); | |
60a11774 | 151 | |
cf8e3474 | 152 | unsigned long long ns2usecs(cycle_t nsec) |
bc0c38d1 SR |
153 | { |
154 | nsec += 500; | |
155 | do_div(nsec, 1000); | |
156 | return nsec; | |
157 | } | |
158 | ||
4fcdae83 SR |
159 | /* |
160 | * The global_trace is the descriptor that holds the tracing | |
161 | * buffers for the live tracing. For each CPU, it contains | |
162 | * a link list of pages that will store trace entries. The | |
163 | * page descriptor of the pages in the memory is used to hold | |
164 | * the link list by linking the lru item in the page descriptor | |
165 | * to each of the pages in the buffer per CPU. | |
166 | * | |
167 | * For each active CPU there is a data field that holds the | |
168 | * pages for the buffer for that CPU. Each CPU has the same number | |
169 | * of pages allocated for its buffer. | |
170 | */ | |
bc0c38d1 SR |
171 | static struct trace_array global_trace; |
172 | ||
173 | static DEFINE_PER_CPU(struct trace_array_cpu, global_trace_cpu); | |
174 | ||
eb02ce01 TZ |
175 | int filter_current_check_discard(struct ftrace_event_call *call, void *rec, |
176 | struct ring_buffer_event *event) | |
177 | { | |
178 | return filter_check_discard(call, rec, global_trace.buffer, event); | |
179 | } | |
17c873ec | 180 | EXPORT_SYMBOL_GPL(filter_current_check_discard); |
eb02ce01 | 181 | |
37886f6a SR |
182 | cycle_t ftrace_now(int cpu) |
183 | { | |
184 | u64 ts; | |
185 | ||
186 | /* Early boot up does not have a buffer yet */ | |
187 | if (!global_trace.buffer) | |
188 | return trace_clock_local(); | |
189 | ||
190 | ts = ring_buffer_time_stamp(global_trace.buffer, cpu); | |
191 | ring_buffer_normalize_time_stamp(global_trace.buffer, cpu, &ts); | |
192 | ||
193 | return ts; | |
194 | } | |
bc0c38d1 | 195 | |
4fcdae83 SR |
196 | /* |
197 | * The max_tr is used to snapshot the global_trace when a maximum | |
198 | * latency is reached. Some tracers will use this to store a maximum | |
199 | * trace while it continues examining live traces. | |
200 | * | |
201 | * The buffers for the max_tr are set up the same as the global_trace. | |
202 | * When a snapshot is taken, the link list of the max_tr is swapped | |
203 | * with the link list of the global_trace and the buffers are reset for | |
204 | * the global_trace so the tracing can continue. | |
205 | */ | |
bc0c38d1 SR |
206 | static struct trace_array max_tr; |
207 | ||
208 | static DEFINE_PER_CPU(struct trace_array_cpu, max_data); | |
209 | ||
4fcdae83 | 210 | /* tracer_enabled is used to toggle activation of a tracer */ |
26994ead | 211 | static int tracer_enabled = 1; |
4fcdae83 | 212 | |
9036990d SR |
213 | /** |
214 | * tracing_is_enabled - return tracer_enabled status | |
215 | * | |
216 | * This function is used by other tracers to know the status | |
217 | * of the tracer_enabled flag. Tracers may use this function | |
218 | * to know if it should enable their features when starting | |
219 | * up. See irqsoff tracer for an example (start_irqsoff_tracer). | |
220 | */ | |
221 | int tracing_is_enabled(void) | |
222 | { | |
223 | return tracer_enabled; | |
224 | } | |
225 | ||
4fcdae83 | 226 | /* |
3928a8a2 SR |
227 | * trace_buf_size is the size in bytes that is allocated |
228 | * for a buffer. Note, the number of bytes is always rounded | |
229 | * to page size. | |
3f5a54e3 SR |
230 | * |
231 | * This number is purposely set to a low number of 16384. | |
232 | * If the dump on oops happens, it will be much appreciated | |
233 | * to not have to wait for all that output. Anyway this can be | |
234 | * boot time and run time configurable. | |
4fcdae83 | 235 | */ |
3928a8a2 | 236 | #define TRACE_BUF_SIZE_DEFAULT 1441792UL /* 16384 * 88 (sizeof(entry)) */ |
3f5a54e3 | 237 | |
3928a8a2 | 238 | static unsigned long trace_buf_size = TRACE_BUF_SIZE_DEFAULT; |
bc0c38d1 | 239 | |
4fcdae83 | 240 | /* trace_types holds a link list of available tracers. */ |
bc0c38d1 | 241 | static struct tracer *trace_types __read_mostly; |
4fcdae83 SR |
242 | |
243 | /* current_trace points to the tracer that is currently active */ | |
bc0c38d1 | 244 | static struct tracer *current_trace __read_mostly; |
4fcdae83 SR |
245 | |
246 | /* | |
247 | * max_tracer_type_len is used to simplify the allocating of | |
248 | * buffers to read userspace tracer names. We keep track of | |
249 | * the longest tracer name registered. | |
250 | */ | |
bc0c38d1 SR |
251 | static int max_tracer_type_len; |
252 | ||
4fcdae83 SR |
253 | /* |
254 | * trace_types_lock is used to protect the trace_types list. | |
255 | * This lock is also used to keep user access serialized. | |
256 | * Accesses from userspace will grab this lock while userspace | |
257 | * activities happen inside the kernel. | |
258 | */ | |
bc0c38d1 | 259 | static DEFINE_MUTEX(trace_types_lock); |
4fcdae83 SR |
260 | |
261 | /* trace_wait is a waitqueue for tasks blocked on trace_poll */ | |
4e655519 IM |
262 | static DECLARE_WAIT_QUEUE_HEAD(trace_wait); |
263 | ||
ee6bce52 | 264 | /* trace_flags holds trace_options default values */ |
12ef7d44 | 265 | unsigned long trace_flags = TRACE_ITER_PRINT_PARENT | TRACE_ITER_PRINTK | |
a2a16d6a SR |
266 | TRACE_ITER_ANNOTATE | TRACE_ITER_CONTEXT_INFO | TRACE_ITER_SLEEP_TIME | |
267 | TRACE_ITER_GRAPH_TIME; | |
4e655519 | 268 | |
4fcdae83 SR |
269 | /** |
270 | * trace_wake_up - wake up tasks waiting for trace input | |
271 | * | |
272 | * Simply wakes up any task that is blocked on the trace_wait | |
273 | * queue. These is used with trace_poll for tasks polling the trace. | |
274 | */ | |
4e655519 IM |
275 | void trace_wake_up(void) |
276 | { | |
017730c1 IM |
277 | /* |
278 | * The runqueue_is_locked() can fail, but this is the best we | |
279 | * have for now: | |
280 | */ | |
281 | if (!(trace_flags & TRACE_ITER_BLOCK) && !runqueue_is_locked()) | |
4e655519 IM |
282 | wake_up(&trace_wait); |
283 | } | |
bc0c38d1 | 284 | |
3928a8a2 | 285 | static int __init set_buf_size(char *str) |
bc0c38d1 | 286 | { |
3928a8a2 | 287 | unsigned long buf_size; |
c6caeeb1 | 288 | |
bc0c38d1 SR |
289 | if (!str) |
290 | return 0; | |
9d612bef | 291 | buf_size = memparse(str, &str); |
c6caeeb1 | 292 | /* nr_entries can not be zero */ |
9d612bef | 293 | if (buf_size == 0) |
c6caeeb1 | 294 | return 0; |
3928a8a2 | 295 | trace_buf_size = buf_size; |
bc0c38d1 SR |
296 | return 1; |
297 | } | |
3928a8a2 | 298 | __setup("trace_buf_size=", set_buf_size); |
bc0c38d1 | 299 | |
57f50be1 SR |
300 | unsigned long nsecs_to_usecs(unsigned long nsecs) |
301 | { | |
302 | return nsecs / 1000; | |
303 | } | |
304 | ||
4fcdae83 | 305 | /* These must match the bit postions in trace_iterator_flags */ |
bc0c38d1 SR |
306 | static const char *trace_options[] = { |
307 | "print-parent", | |
308 | "sym-offset", | |
309 | "sym-addr", | |
310 | "verbose", | |
f9896bf3 | 311 | "raw", |
5e3ca0ec | 312 | "hex", |
cb0f12aa | 313 | "bin", |
2a2cc8f7 | 314 | "block", |
86387f7e | 315 | "stacktrace", |
4ac3ba41 | 316 | "sched-tree", |
5e1607a0 | 317 | "trace_printk", |
b2a866f9 | 318 | "ftrace_preempt", |
9f029e83 | 319 | "branch", |
12ef7d44 | 320 | "annotate", |
02b67518 | 321 | "userstacktrace", |
b54d3de9 | 322 | "sym-userobj", |
66896a85 | 323 | "printk-msg-only", |
c4a8e8be | 324 | "context-info", |
c032ef64 | 325 | "latency-format", |
be6f164a | 326 | "sleep-time", |
a2a16d6a | 327 | "graph-time", |
bc0c38d1 SR |
328 | NULL |
329 | }; | |
330 | ||
5079f326 Z |
331 | static struct { |
332 | u64 (*func)(void); | |
333 | const char *name; | |
334 | } trace_clocks[] = { | |
335 | { trace_clock_local, "local" }, | |
336 | { trace_clock_global, "global" }, | |
337 | }; | |
338 | ||
339 | int trace_clock_id; | |
340 | ||
4fcdae83 SR |
341 | /* |
342 | * ftrace_max_lock is used to protect the swapping of buffers | |
343 | * when taking a max snapshot. The buffers themselves are | |
344 | * protected by per_cpu spinlocks. But the action of the swap | |
345 | * needs its own lock. | |
346 | * | |
347 | * This is defined as a raw_spinlock_t in order to help | |
348 | * with performance when lockdep debugging is enabled. | |
349 | */ | |
92205c23 SR |
350 | static raw_spinlock_t ftrace_max_lock = |
351 | (raw_spinlock_t)__RAW_SPIN_LOCK_UNLOCKED; | |
bc0c38d1 SR |
352 | |
353 | /* | |
354 | * Copy the new maximum trace into the separate maximum-trace | |
355 | * structure. (this way the maximum trace is permanently saved, | |
156f5a78 | 356 | * for later retrieval via /sys/kernel/debug/tracing/latency_trace) |
bc0c38d1 | 357 | */ |
e309b41d | 358 | static void |
bc0c38d1 SR |
359 | __update_max_tr(struct trace_array *tr, struct task_struct *tsk, int cpu) |
360 | { | |
361 | struct trace_array_cpu *data = tr->data[cpu]; | |
362 | ||
363 | max_tr.cpu = cpu; | |
364 | max_tr.time_start = data->preempt_timestamp; | |
365 | ||
366 | data = max_tr.data[cpu]; | |
367 | data->saved_latency = tracing_max_latency; | |
368 | ||
369 | memcpy(data->comm, tsk->comm, TASK_COMM_LEN); | |
370 | data->pid = tsk->pid; | |
b6dff3ec | 371 | data->uid = task_uid(tsk); |
bc0c38d1 SR |
372 | data->nice = tsk->static_prio - 20 - MAX_RT_PRIO; |
373 | data->policy = tsk->policy; | |
374 | data->rt_priority = tsk->rt_priority; | |
375 | ||
376 | /* record this tasks comm */ | |
af513098 | 377 | tracing_record_cmdline(tsk); |
bc0c38d1 SR |
378 | } |
379 | ||
6c6c2796 PP |
380 | ssize_t trace_seq_to_user(struct trace_seq *s, char __user *ubuf, size_t cnt) |
381 | { | |
382 | int len; | |
383 | int ret; | |
384 | ||
2dc5d12b SR |
385 | if (!cnt) |
386 | return 0; | |
387 | ||
6c6c2796 PP |
388 | if (s->len <= s->readpos) |
389 | return -EBUSY; | |
390 | ||
391 | len = s->len - s->readpos; | |
392 | if (cnt > len) | |
393 | cnt = len; | |
394 | ret = copy_to_user(ubuf, s->buffer + s->readpos, cnt); | |
2dc5d12b | 395 | if (ret == cnt) |
6c6c2796 PP |
396 | return -EFAULT; |
397 | ||
2dc5d12b SR |
398 | cnt -= ret; |
399 | ||
e74da523 | 400 | s->readpos += cnt; |
6c6c2796 | 401 | return cnt; |
214023c3 SR |
402 | } |
403 | ||
b8b94265 | 404 | static ssize_t trace_seq_to_buffer(struct trace_seq *s, void *buf, size_t cnt) |
3c56819b EGM |
405 | { |
406 | int len; | |
407 | void *ret; | |
408 | ||
409 | if (s->len <= s->readpos) | |
410 | return -EBUSY; | |
411 | ||
412 | len = s->len - s->readpos; | |
413 | if (cnt > len) | |
414 | cnt = len; | |
415 | ret = memcpy(buf, s->buffer + s->readpos, cnt); | |
416 | if (!ret) | |
417 | return -EFAULT; | |
418 | ||
e74da523 | 419 | s->readpos += cnt; |
3c56819b EGM |
420 | return cnt; |
421 | } | |
422 | ||
4fcdae83 SR |
423 | /** |
424 | * update_max_tr - snapshot all trace buffers from global_trace to max_tr | |
425 | * @tr: tracer | |
426 | * @tsk: the task with the latency | |
427 | * @cpu: The cpu that initiated the trace. | |
428 | * | |
429 | * Flip the buffers between the @tr and the max_tr and record information | |
430 | * about which task was the cause of this latency. | |
431 | */ | |
e309b41d | 432 | void |
bc0c38d1 SR |
433 | update_max_tr(struct trace_array *tr, struct task_struct *tsk, int cpu) |
434 | { | |
3928a8a2 | 435 | struct ring_buffer *buf = tr->buffer; |
bc0c38d1 | 436 | |
4c11d7ae | 437 | WARN_ON_ONCE(!irqs_disabled()); |
92205c23 | 438 | __raw_spin_lock(&ftrace_max_lock); |
3928a8a2 SR |
439 | |
440 | tr->buffer = max_tr.buffer; | |
441 | max_tr.buffer = buf; | |
442 | ||
d769041f | 443 | ftrace_disable_cpu(); |
3928a8a2 | 444 | ring_buffer_reset(tr->buffer); |
d769041f | 445 | ftrace_enable_cpu(); |
bc0c38d1 SR |
446 | |
447 | __update_max_tr(tr, tsk, cpu); | |
92205c23 | 448 | __raw_spin_unlock(&ftrace_max_lock); |
bc0c38d1 SR |
449 | } |
450 | ||
451 | /** | |
452 | * update_max_tr_single - only copy one trace over, and reset the rest | |
453 | * @tr - tracer | |
454 | * @tsk - task with the latency | |
455 | * @cpu - the cpu of the buffer to copy. | |
4fcdae83 SR |
456 | * |
457 | * Flip the trace of a single CPU buffer between the @tr and the max_tr. | |
bc0c38d1 | 458 | */ |
e309b41d | 459 | void |
bc0c38d1 SR |
460 | update_max_tr_single(struct trace_array *tr, struct task_struct *tsk, int cpu) |
461 | { | |
3928a8a2 | 462 | int ret; |
bc0c38d1 | 463 | |
4c11d7ae | 464 | WARN_ON_ONCE(!irqs_disabled()); |
92205c23 | 465 | __raw_spin_lock(&ftrace_max_lock); |
bc0c38d1 | 466 | |
d769041f SR |
467 | ftrace_disable_cpu(); |
468 | ||
3928a8a2 SR |
469 | ring_buffer_reset(max_tr.buffer); |
470 | ret = ring_buffer_swap_cpu(max_tr.buffer, tr->buffer, cpu); | |
471 | ||
d769041f SR |
472 | ftrace_enable_cpu(); |
473 | ||
97b17efe | 474 | WARN_ON_ONCE(ret && ret != -EAGAIN); |
bc0c38d1 SR |
475 | |
476 | __update_max_tr(tr, tsk, cpu); | |
92205c23 | 477 | __raw_spin_unlock(&ftrace_max_lock); |
bc0c38d1 SR |
478 | } |
479 | ||
4fcdae83 SR |
480 | /** |
481 | * register_tracer - register a tracer with the ftrace system. | |
482 | * @type - the plugin for the tracer | |
483 | * | |
484 | * Register a new plugin tracer. | |
485 | */ | |
bc0c38d1 | 486 | int register_tracer(struct tracer *type) |
e7669b8e HE |
487 | __releases(kernel_lock) |
488 | __acquires(kernel_lock) | |
bc0c38d1 SR |
489 | { |
490 | struct tracer *t; | |
491 | int len; | |
492 | int ret = 0; | |
493 | ||
494 | if (!type->name) { | |
495 | pr_info("Tracer must have a name\n"); | |
496 | return -1; | |
497 | } | |
498 | ||
86fa2f60 IM |
499 | /* |
500 | * When this gets called we hold the BKL which means that | |
501 | * preemption is disabled. Various trace selftests however | |
502 | * need to disable and enable preemption for successful tests. | |
503 | * So we drop the BKL here and grab it after the tests again. | |
504 | */ | |
505 | unlock_kernel(); | |
bc0c38d1 | 506 | mutex_lock(&trace_types_lock); |
86fa2f60 | 507 | |
8e1b82e0 FW |
508 | tracing_selftest_running = true; |
509 | ||
bc0c38d1 SR |
510 | for (t = trace_types; t; t = t->next) { |
511 | if (strcmp(type->name, t->name) == 0) { | |
512 | /* already found */ | |
513 | pr_info("Trace %s already registered\n", | |
514 | type->name); | |
515 | ret = -1; | |
516 | goto out; | |
517 | } | |
518 | } | |
519 | ||
adf9f195 FW |
520 | if (!type->set_flag) |
521 | type->set_flag = &dummy_set_flag; | |
522 | if (!type->flags) | |
523 | type->flags = &dummy_tracer_flags; | |
524 | else | |
525 | if (!type->flags->opts) | |
526 | type->flags->opts = dummy_tracer_opt; | |
6eaaa5d5 FW |
527 | if (!type->wait_pipe) |
528 | type->wait_pipe = default_wait_pipe; | |
529 | ||
adf9f195 | 530 | |
60a11774 | 531 | #ifdef CONFIG_FTRACE_STARTUP_TEST |
b2821ae6 | 532 | if (type->selftest && !tracing_selftest_disabled) { |
60a11774 | 533 | struct tracer *saved_tracer = current_trace; |
60a11774 | 534 | struct trace_array *tr = &global_trace; |
60a11774 | 535 | int i; |
ff32504f | 536 | |
60a11774 SR |
537 | /* |
538 | * Run a selftest on this tracer. | |
539 | * Here we reset the trace buffer, and set the current | |
540 | * tracer to be this tracer. The tracer can then run some | |
541 | * internal tracing to verify that everything is in order. | |
542 | * If we fail, we do not register this tracer. | |
543 | */ | |
86fa2f60 | 544 | for_each_tracing_cpu(i) |
3928a8a2 | 545 | tracing_reset(tr, i); |
86fa2f60 | 546 | |
60a11774 | 547 | current_trace = type; |
60a11774 SR |
548 | /* the test is responsible for initializing and enabling */ |
549 | pr_info("Testing tracer %s: ", type->name); | |
550 | ret = type->selftest(type, tr); | |
551 | /* the test is responsible for resetting too */ | |
552 | current_trace = saved_tracer; | |
60a11774 SR |
553 | if (ret) { |
554 | printk(KERN_CONT "FAILED!\n"); | |
555 | goto out; | |
556 | } | |
1d4db00a | 557 | /* Only reset on passing, to avoid touching corrupted buffers */ |
86fa2f60 | 558 | for_each_tracing_cpu(i) |
3928a8a2 | 559 | tracing_reset(tr, i); |
86fa2f60 | 560 | |
60a11774 SR |
561 | printk(KERN_CONT "PASSED\n"); |
562 | } | |
563 | #endif | |
564 | ||
bc0c38d1 SR |
565 | type->next = trace_types; |
566 | trace_types = type; | |
567 | len = strlen(type->name); | |
568 | if (len > max_tracer_type_len) | |
569 | max_tracer_type_len = len; | |
60a11774 | 570 | |
bc0c38d1 | 571 | out: |
8e1b82e0 | 572 | tracing_selftest_running = false; |
bc0c38d1 SR |
573 | mutex_unlock(&trace_types_lock); |
574 | ||
dac74940 SR |
575 | if (ret || !default_bootup_tracer) |
576 | goto out_unlock; | |
577 | ||
578 | if (strncmp(default_bootup_tracer, type->name, BOOTUP_TRACER_SIZE)) | |
579 | goto out_unlock; | |
580 | ||
581 | printk(KERN_INFO "Starting tracer '%s'\n", type->name); | |
582 | /* Do we want this tracer to start on bootup? */ | |
583 | tracing_set_tracer(type->name); | |
584 | default_bootup_tracer = NULL; | |
585 | /* disable other selftests, since this will break it. */ | |
586 | tracing_selftest_disabled = 1; | |
b2821ae6 | 587 | #ifdef CONFIG_FTRACE_STARTUP_TEST |
dac74940 SR |
588 | printk(KERN_INFO "Disabling FTRACE selftests due to running tracer '%s'\n", |
589 | type->name); | |
b2821ae6 | 590 | #endif |
b2821ae6 | 591 | |
dac74940 | 592 | out_unlock: |
b2821ae6 | 593 | lock_kernel(); |
bc0c38d1 SR |
594 | return ret; |
595 | } | |
596 | ||
597 | void unregister_tracer(struct tracer *type) | |
598 | { | |
599 | struct tracer **t; | |
600 | int len; | |
601 | ||
602 | mutex_lock(&trace_types_lock); | |
603 | for (t = &trace_types; *t; t = &(*t)->next) { | |
604 | if (*t == type) | |
605 | goto found; | |
606 | } | |
607 | pr_info("Trace %s not registered\n", type->name); | |
608 | goto out; | |
609 | ||
610 | found: | |
611 | *t = (*t)->next; | |
b5db03c4 ACM |
612 | |
613 | if (type == current_trace && tracer_enabled) { | |
614 | tracer_enabled = 0; | |
615 | tracing_stop(); | |
616 | if (current_trace->stop) | |
617 | current_trace->stop(&global_trace); | |
618 | current_trace = &nop_trace; | |
619 | } | |
620 | ||
bc0c38d1 SR |
621 | if (strlen(type->name) != max_tracer_type_len) |
622 | goto out; | |
623 | ||
624 | max_tracer_type_len = 0; | |
625 | for (t = &trace_types; *t; t = &(*t)->next) { | |
626 | len = strlen((*t)->name); | |
627 | if (len > max_tracer_type_len) | |
628 | max_tracer_type_len = len; | |
629 | } | |
630 | out: | |
631 | mutex_unlock(&trace_types_lock); | |
632 | } | |
633 | ||
3928a8a2 | 634 | void tracing_reset(struct trace_array *tr, int cpu) |
bc0c38d1 | 635 | { |
d769041f | 636 | ftrace_disable_cpu(); |
3928a8a2 | 637 | ring_buffer_reset_cpu(tr->buffer, cpu); |
d769041f | 638 | ftrace_enable_cpu(); |
bc0c38d1 SR |
639 | } |
640 | ||
213cc060 PE |
641 | void tracing_reset_online_cpus(struct trace_array *tr) |
642 | { | |
643 | int cpu; | |
644 | ||
645 | tr->time_start = ftrace_now(tr->cpu); | |
646 | ||
647 | for_each_online_cpu(cpu) | |
648 | tracing_reset(tr, cpu); | |
649 | } | |
650 | ||
9456f0fa SR |
651 | void tracing_reset_current(int cpu) |
652 | { | |
653 | tracing_reset(&global_trace, cpu); | |
654 | } | |
655 | ||
656 | void tracing_reset_current_online_cpus(void) | |
657 | { | |
658 | tracing_reset_online_cpus(&global_trace); | |
659 | } | |
660 | ||
bc0c38d1 | 661 | #define SAVED_CMDLINES 128 |
2c7eea4c | 662 | #define NO_CMDLINE_MAP UINT_MAX |
bc0c38d1 SR |
663 | static unsigned map_pid_to_cmdline[PID_MAX_DEFAULT+1]; |
664 | static unsigned map_cmdline_to_pid[SAVED_CMDLINES]; | |
665 | static char saved_cmdlines[SAVED_CMDLINES][TASK_COMM_LEN]; | |
666 | static int cmdline_idx; | |
efed792d | 667 | static raw_spinlock_t trace_cmdline_lock = __RAW_SPIN_LOCK_UNLOCKED; |
25b0b44a | 668 | |
25b0b44a | 669 | /* temporary disable recording */ |
4fd27358 | 670 | static atomic_t trace_record_cmdline_disabled __read_mostly; |
bc0c38d1 SR |
671 | |
672 | static void trace_init_cmdlines(void) | |
673 | { | |
2c7eea4c TG |
674 | memset(&map_pid_to_cmdline, NO_CMDLINE_MAP, sizeof(map_pid_to_cmdline)); |
675 | memset(&map_cmdline_to_pid, NO_CMDLINE_MAP, sizeof(map_cmdline_to_pid)); | |
bc0c38d1 SR |
676 | cmdline_idx = 0; |
677 | } | |
678 | ||
0f048701 SR |
679 | static int trace_stop_count; |
680 | static DEFINE_SPINLOCK(tracing_start_lock); | |
681 | ||
69bb54ec SR |
682 | /** |
683 | * ftrace_off_permanent - disable all ftrace code permanently | |
684 | * | |
685 | * This should only be called when a serious anomally has | |
686 | * been detected. This will turn off the function tracing, | |
687 | * ring buffers, and other tracing utilites. It takes no | |
688 | * locks and can be called from any context. | |
689 | */ | |
690 | void ftrace_off_permanent(void) | |
691 | { | |
692 | tracing_disabled = 1; | |
693 | ftrace_stop(); | |
694 | tracing_off_permanent(); | |
695 | } | |
696 | ||
0f048701 SR |
697 | /** |
698 | * tracing_start - quick start of the tracer | |
699 | * | |
700 | * If tracing is enabled but was stopped by tracing_stop, | |
701 | * this will start the tracer back up. | |
702 | */ | |
703 | void tracing_start(void) | |
704 | { | |
705 | struct ring_buffer *buffer; | |
706 | unsigned long flags; | |
707 | ||
708 | if (tracing_disabled) | |
709 | return; | |
710 | ||
711 | spin_lock_irqsave(&tracing_start_lock, flags); | |
b06a8301 SR |
712 | if (--trace_stop_count) { |
713 | if (trace_stop_count < 0) { | |
714 | /* Someone screwed up their debugging */ | |
715 | WARN_ON_ONCE(1); | |
716 | trace_stop_count = 0; | |
717 | } | |
0f048701 SR |
718 | goto out; |
719 | } | |
720 | ||
721 | ||
722 | buffer = global_trace.buffer; | |
723 | if (buffer) | |
724 | ring_buffer_record_enable(buffer); | |
725 | ||
726 | buffer = max_tr.buffer; | |
727 | if (buffer) | |
728 | ring_buffer_record_enable(buffer); | |
729 | ||
730 | ftrace_start(); | |
731 | out: | |
732 | spin_unlock_irqrestore(&tracing_start_lock, flags); | |
733 | } | |
734 | ||
735 | /** | |
736 | * tracing_stop - quick stop of the tracer | |
737 | * | |
738 | * Light weight way to stop tracing. Use in conjunction with | |
739 | * tracing_start. | |
740 | */ | |
741 | void tracing_stop(void) | |
742 | { | |
743 | struct ring_buffer *buffer; | |
744 | unsigned long flags; | |
745 | ||
746 | ftrace_stop(); | |
747 | spin_lock_irqsave(&tracing_start_lock, flags); | |
748 | if (trace_stop_count++) | |
749 | goto out; | |
750 | ||
751 | buffer = global_trace.buffer; | |
752 | if (buffer) | |
753 | ring_buffer_record_disable(buffer); | |
754 | ||
755 | buffer = max_tr.buffer; | |
756 | if (buffer) | |
757 | ring_buffer_record_disable(buffer); | |
758 | ||
759 | out: | |
760 | spin_unlock_irqrestore(&tracing_start_lock, flags); | |
761 | } | |
762 | ||
e309b41d | 763 | void trace_stop_cmdline_recording(void); |
bc0c38d1 | 764 | |
e309b41d | 765 | static void trace_save_cmdline(struct task_struct *tsk) |
bc0c38d1 | 766 | { |
a635cf04 | 767 | unsigned pid, idx; |
bc0c38d1 SR |
768 | |
769 | if (!tsk->pid || unlikely(tsk->pid > PID_MAX_DEFAULT)) | |
770 | return; | |
771 | ||
772 | /* | |
773 | * It's not the end of the world if we don't get | |
774 | * the lock, but we also don't want to spin | |
775 | * nor do we want to disable interrupts, | |
776 | * so if we miss here, then better luck next time. | |
777 | */ | |
efed792d | 778 | if (!__raw_spin_trylock(&trace_cmdline_lock)) |
bc0c38d1 SR |
779 | return; |
780 | ||
781 | idx = map_pid_to_cmdline[tsk->pid]; | |
2c7eea4c | 782 | if (idx == NO_CMDLINE_MAP) { |
bc0c38d1 SR |
783 | idx = (cmdline_idx + 1) % SAVED_CMDLINES; |
784 | ||
a635cf04 CE |
785 | /* |
786 | * Check whether the cmdline buffer at idx has a pid | |
787 | * mapped. We are going to overwrite that entry so we | |
788 | * need to clear the map_pid_to_cmdline. Otherwise we | |
789 | * would read the new comm for the old pid. | |
790 | */ | |
791 | pid = map_cmdline_to_pid[idx]; | |
792 | if (pid != NO_CMDLINE_MAP) | |
793 | map_pid_to_cmdline[pid] = NO_CMDLINE_MAP; | |
bc0c38d1 | 794 | |
a635cf04 | 795 | map_cmdline_to_pid[idx] = tsk->pid; |
bc0c38d1 SR |
796 | map_pid_to_cmdline[tsk->pid] = idx; |
797 | ||
798 | cmdline_idx = idx; | |
799 | } | |
800 | ||
801 | memcpy(&saved_cmdlines[idx], tsk->comm, TASK_COMM_LEN); | |
802 | ||
efed792d | 803 | __raw_spin_unlock(&trace_cmdline_lock); |
bc0c38d1 SR |
804 | } |
805 | ||
4ca53085 | 806 | void trace_find_cmdline(int pid, char comm[]) |
bc0c38d1 | 807 | { |
bc0c38d1 SR |
808 | unsigned map; |
809 | ||
4ca53085 SR |
810 | if (!pid) { |
811 | strcpy(comm, "<idle>"); | |
812 | return; | |
813 | } | |
bc0c38d1 | 814 | |
4ca53085 SR |
815 | if (pid > PID_MAX_DEFAULT) { |
816 | strcpy(comm, "<...>"); | |
817 | return; | |
818 | } | |
bc0c38d1 | 819 | |
5b6045a9 | 820 | preempt_disable(); |
4ca53085 | 821 | __raw_spin_lock(&trace_cmdline_lock); |
bc0c38d1 | 822 | map = map_pid_to_cmdline[pid]; |
50d88758 TG |
823 | if (map != NO_CMDLINE_MAP) |
824 | strcpy(comm, saved_cmdlines[map]); | |
825 | else | |
826 | strcpy(comm, "<...>"); | |
bc0c38d1 | 827 | |
4ca53085 | 828 | __raw_spin_unlock(&trace_cmdline_lock); |
5b6045a9 | 829 | preempt_enable(); |
bc0c38d1 SR |
830 | } |
831 | ||
e309b41d | 832 | void tracing_record_cmdline(struct task_struct *tsk) |
bc0c38d1 | 833 | { |
18aecd36 TG |
834 | if (atomic_read(&trace_record_cmdline_disabled) || !tracer_enabled || |
835 | !tracing_is_on()) | |
bc0c38d1 SR |
836 | return; |
837 | ||
838 | trace_save_cmdline(tsk); | |
839 | } | |
840 | ||
45dcd8b8 | 841 | void |
38697053 SR |
842 | tracing_generic_entry_update(struct trace_entry *entry, unsigned long flags, |
843 | int pc) | |
bc0c38d1 SR |
844 | { |
845 | struct task_struct *tsk = current; | |
bc0c38d1 | 846 | |
777e208d SR |
847 | entry->preempt_count = pc & 0xff; |
848 | entry->pid = (tsk) ? tsk->pid : 0; | |
ef18012b | 849 | entry->tgid = (tsk) ? tsk->tgid : 0; |
777e208d | 850 | entry->flags = |
9244489a | 851 | #ifdef CONFIG_TRACE_IRQFLAGS_SUPPORT |
2e2ca155 | 852 | (irqs_disabled_flags(flags) ? TRACE_FLAG_IRQS_OFF : 0) | |
9244489a SR |
853 | #else |
854 | TRACE_FLAG_IRQS_NOSUPPORT | | |
855 | #endif | |
bc0c38d1 SR |
856 | ((pc & HARDIRQ_MASK) ? TRACE_FLAG_HARDIRQ : 0) | |
857 | ((pc & SOFTIRQ_MASK) ? TRACE_FLAG_SOFTIRQ : 0) | | |
858 | (need_resched() ? TRACE_FLAG_NEED_RESCHED : 0); | |
859 | } | |
f413cdb8 | 860 | EXPORT_SYMBOL_GPL(tracing_generic_entry_update); |
bc0c38d1 | 861 | |
51a763dd | 862 | struct ring_buffer_event *trace_buffer_lock_reserve(struct trace_array *tr, |
7a4f453b | 863 | int type, |
51a763dd ACM |
864 | unsigned long len, |
865 | unsigned long flags, int pc) | |
866 | { | |
867 | struct ring_buffer_event *event; | |
868 | ||
869 | event = ring_buffer_lock_reserve(tr->buffer, len); | |
870 | if (event != NULL) { | |
871 | struct trace_entry *ent = ring_buffer_event_data(event); | |
872 | ||
873 | tracing_generic_entry_update(ent, flags, pc); | |
874 | ent->type = type; | |
875 | } | |
876 | ||
877 | return event; | |
878 | } | |
51a763dd | 879 | |
07edf712 FW |
880 | static inline void __trace_buffer_unlock_commit(struct trace_array *tr, |
881 | struct ring_buffer_event *event, | |
882 | unsigned long flags, int pc, | |
883 | int wake) | |
51a763dd ACM |
884 | { |
885 | ring_buffer_unlock_commit(tr->buffer, event); | |
886 | ||
887 | ftrace_trace_stack(tr, flags, 6, pc); | |
888 | ftrace_trace_userstack(tr, flags, pc); | |
07edf712 FW |
889 | |
890 | if (wake) | |
891 | trace_wake_up(); | |
892 | } | |
893 | ||
894 | void trace_buffer_unlock_commit(struct trace_array *tr, | |
895 | struct ring_buffer_event *event, | |
896 | unsigned long flags, int pc) | |
897 | { | |
898 | __trace_buffer_unlock_commit(tr, event, flags, pc, 1); | |
51a763dd ACM |
899 | } |
900 | ||
ef5580d0 | 901 | struct ring_buffer_event * |
7a4f453b | 902 | trace_current_buffer_lock_reserve(int type, unsigned long len, |
ef5580d0 SR |
903 | unsigned long flags, int pc) |
904 | { | |
905 | return trace_buffer_lock_reserve(&global_trace, | |
906 | type, len, flags, pc); | |
907 | } | |
94487d6d | 908 | EXPORT_SYMBOL_GPL(trace_current_buffer_lock_reserve); |
ef5580d0 SR |
909 | |
910 | void trace_current_buffer_unlock_commit(struct ring_buffer_event *event, | |
911 | unsigned long flags, int pc) | |
912 | { | |
77d9f465 | 913 | __trace_buffer_unlock_commit(&global_trace, event, flags, pc, 1); |
07edf712 | 914 | } |
94487d6d | 915 | EXPORT_SYMBOL_GPL(trace_current_buffer_unlock_commit); |
07edf712 FW |
916 | |
917 | void trace_nowake_buffer_unlock_commit(struct ring_buffer_event *event, | |
918 | unsigned long flags, int pc) | |
919 | { | |
77d9f465 SR |
920 | __trace_buffer_unlock_commit(&global_trace, event, flags, pc, 0); |
921 | } | |
94487d6d | 922 | EXPORT_SYMBOL_GPL(trace_nowake_buffer_unlock_commit); |
77d9f465 SR |
923 | |
924 | void trace_current_buffer_discard_commit(struct ring_buffer_event *event) | |
925 | { | |
926 | ring_buffer_discard_commit(global_trace.buffer, event); | |
ef5580d0 | 927 | } |
12acd473 | 928 | EXPORT_SYMBOL_GPL(trace_current_buffer_discard_commit); |
ef5580d0 | 929 | |
e309b41d | 930 | void |
7be42151 | 931 | trace_function(struct trace_array *tr, |
38697053 SR |
932 | unsigned long ip, unsigned long parent_ip, unsigned long flags, |
933 | int pc) | |
bc0c38d1 | 934 | { |
e1112b4d | 935 | struct ftrace_event_call *call = &event_function; |
3928a8a2 | 936 | struct ring_buffer_event *event; |
777e208d | 937 | struct ftrace_entry *entry; |
bc0c38d1 | 938 | |
d769041f SR |
939 | /* If we are reading the ring buffer, don't trace */ |
940 | if (unlikely(local_read(&__get_cpu_var(ftrace_cpu_disabled)))) | |
941 | return; | |
942 | ||
51a763dd ACM |
943 | event = trace_buffer_lock_reserve(tr, TRACE_FN, sizeof(*entry), |
944 | flags, pc); | |
3928a8a2 SR |
945 | if (!event) |
946 | return; | |
947 | entry = ring_buffer_event_data(event); | |
777e208d SR |
948 | entry->ip = ip; |
949 | entry->parent_ip = parent_ip; | |
e1112b4d | 950 | |
eb02ce01 TZ |
951 | if (!filter_check_discard(call, entry, tr->buffer, event)) |
952 | ring_buffer_unlock_commit(tr->buffer, event); | |
bc0c38d1 SR |
953 | } |
954 | ||
e309b41d | 955 | void |
2e0f5761 | 956 | ftrace(struct trace_array *tr, struct trace_array_cpu *data, |
38697053 SR |
957 | unsigned long ip, unsigned long parent_ip, unsigned long flags, |
958 | int pc) | |
2e0f5761 IM |
959 | { |
960 | if (likely(!atomic_read(&data->disabled))) | |
7be42151 | 961 | trace_function(tr, ip, parent_ip, flags, pc); |
2e0f5761 IM |
962 | } |
963 | ||
c0a0d0d3 | 964 | #ifdef CONFIG_STACKTRACE |
53614991 | 965 | static void __ftrace_trace_stack(struct trace_array *tr, |
53614991 SR |
966 | unsigned long flags, |
967 | int skip, int pc) | |
86387f7e | 968 | { |
e1112b4d | 969 | struct ftrace_event_call *call = &event_kernel_stack; |
3928a8a2 | 970 | struct ring_buffer_event *event; |
777e208d | 971 | struct stack_entry *entry; |
86387f7e IM |
972 | struct stack_trace trace; |
973 | ||
51a763dd ACM |
974 | event = trace_buffer_lock_reserve(tr, TRACE_STACK, |
975 | sizeof(*entry), flags, pc); | |
3928a8a2 SR |
976 | if (!event) |
977 | return; | |
978 | entry = ring_buffer_event_data(event); | |
777e208d | 979 | memset(&entry->caller, 0, sizeof(entry->caller)); |
86387f7e IM |
980 | |
981 | trace.nr_entries = 0; | |
982 | trace.max_entries = FTRACE_STACK_ENTRIES; | |
983 | trace.skip = skip; | |
777e208d | 984 | trace.entries = entry->caller; |
86387f7e IM |
985 | |
986 | save_stack_trace(&trace); | |
eb02ce01 TZ |
987 | if (!filter_check_discard(call, entry, tr->buffer, event)) |
988 | ring_buffer_unlock_commit(tr->buffer, event); | |
f0a920d5 IM |
989 | } |
990 | ||
c0a0d0d3 FW |
991 | void ftrace_trace_stack(struct trace_array *tr, unsigned long flags, int skip, |
992 | int pc) | |
53614991 SR |
993 | { |
994 | if (!(trace_flags & TRACE_ITER_STACKTRACE)) | |
995 | return; | |
996 | ||
7be42151 | 997 | __ftrace_trace_stack(tr, flags, skip, pc); |
53614991 SR |
998 | } |
999 | ||
c0a0d0d3 FW |
1000 | void __trace_stack(struct trace_array *tr, unsigned long flags, int skip, |
1001 | int pc) | |
38697053 | 1002 | { |
7be42151 | 1003 | __ftrace_trace_stack(tr, flags, skip, pc); |
38697053 SR |
1004 | } |
1005 | ||
c0a0d0d3 | 1006 | void ftrace_trace_userstack(struct trace_array *tr, unsigned long flags, int pc) |
02b67518 | 1007 | { |
e1112b4d | 1008 | struct ftrace_event_call *call = &event_user_stack; |
8d7c6a96 | 1009 | struct ring_buffer_event *event; |
02b67518 TE |
1010 | struct userstack_entry *entry; |
1011 | struct stack_trace trace; | |
02b67518 TE |
1012 | |
1013 | if (!(trace_flags & TRACE_ITER_USERSTACKTRACE)) | |
1014 | return; | |
1015 | ||
51a763dd ACM |
1016 | event = trace_buffer_lock_reserve(tr, TRACE_USER_STACK, |
1017 | sizeof(*entry), flags, pc); | |
02b67518 TE |
1018 | if (!event) |
1019 | return; | |
1020 | entry = ring_buffer_event_data(event); | |
02b67518 TE |
1021 | |
1022 | memset(&entry->caller, 0, sizeof(entry->caller)); | |
1023 | ||
1024 | trace.nr_entries = 0; | |
1025 | trace.max_entries = FTRACE_STACK_ENTRIES; | |
1026 | trace.skip = 0; | |
1027 | trace.entries = entry->caller; | |
1028 | ||
1029 | save_stack_trace_user(&trace); | |
eb02ce01 TZ |
1030 | if (!filter_check_discard(call, entry, tr->buffer, event)) |
1031 | ring_buffer_unlock_commit(tr->buffer, event); | |
02b67518 TE |
1032 | } |
1033 | ||
4fd27358 HE |
1034 | #ifdef UNUSED |
1035 | static void __trace_userstack(struct trace_array *tr, unsigned long flags) | |
02b67518 | 1036 | { |
7be42151 | 1037 | ftrace_trace_userstack(tr, flags, preempt_count()); |
02b67518 | 1038 | } |
4fd27358 | 1039 | #endif /* UNUSED */ |
02b67518 | 1040 | |
c0a0d0d3 FW |
1041 | #endif /* CONFIG_STACKTRACE */ |
1042 | ||
38697053 | 1043 | static void |
7be42151 | 1044 | ftrace_trace_special(void *__tr, |
38697053 SR |
1045 | unsigned long arg1, unsigned long arg2, unsigned long arg3, |
1046 | int pc) | |
a4feb834 | 1047 | { |
3928a8a2 | 1048 | struct ring_buffer_event *event; |
a4feb834 | 1049 | struct trace_array *tr = __tr; |
777e208d | 1050 | struct special_entry *entry; |
a4feb834 | 1051 | |
51a763dd ACM |
1052 | event = trace_buffer_lock_reserve(tr, TRACE_SPECIAL, |
1053 | sizeof(*entry), 0, pc); | |
3928a8a2 SR |
1054 | if (!event) |
1055 | return; | |
1056 | entry = ring_buffer_event_data(event); | |
777e208d SR |
1057 | entry->arg1 = arg1; |
1058 | entry->arg2 = arg2; | |
1059 | entry->arg3 = arg3; | |
51a763dd | 1060 | trace_buffer_unlock_commit(tr, event, 0, pc); |
a4feb834 IM |
1061 | } |
1062 | ||
38697053 SR |
1063 | void |
1064 | __trace_special(void *__tr, void *__data, | |
1065 | unsigned long arg1, unsigned long arg2, unsigned long arg3) | |
1066 | { | |
7be42151 | 1067 | ftrace_trace_special(__tr, arg1, arg2, arg3, preempt_count()); |
38697053 SR |
1068 | } |
1069 | ||
4902f884 SR |
1070 | void |
1071 | ftrace_special(unsigned long arg1, unsigned long arg2, unsigned long arg3) | |
1072 | { | |
1073 | struct trace_array *tr = &global_trace; | |
1074 | struct trace_array_cpu *data; | |
5aa1ba6a | 1075 | unsigned long flags; |
4902f884 | 1076 | int cpu; |
38697053 | 1077 | int pc; |
4902f884 | 1078 | |
c76f0694 | 1079 | if (tracing_disabled) |
4902f884 SR |
1080 | return; |
1081 | ||
38697053 | 1082 | pc = preempt_count(); |
5aa1ba6a | 1083 | local_irq_save(flags); |
4902f884 SR |
1084 | cpu = raw_smp_processor_id(); |
1085 | data = tr->data[cpu]; | |
4902f884 | 1086 | |
5aa1ba6a | 1087 | if (likely(atomic_inc_return(&data->disabled) == 1)) |
7be42151 | 1088 | ftrace_trace_special(tr, arg1, arg2, arg3, pc); |
4902f884 | 1089 | |
5aa1ba6a SR |
1090 | atomic_dec(&data->disabled); |
1091 | local_irq_restore(flags); | |
4902f884 SR |
1092 | } |
1093 | ||
769b0441 | 1094 | /** |
48ead020 | 1095 | * trace_vbprintk - write binary msg to tracing buffer |
769b0441 FW |
1096 | * |
1097 | */ | |
40ce74f1 | 1098 | int trace_vbprintk(unsigned long ip, const char *fmt, va_list args) |
769b0441 | 1099 | { |
80370cb7 SR |
1100 | static raw_spinlock_t trace_buf_lock = |
1101 | (raw_spinlock_t)__RAW_SPIN_LOCK_UNLOCKED; | |
769b0441 FW |
1102 | static u32 trace_buf[TRACE_BUF_SIZE]; |
1103 | ||
e1112b4d | 1104 | struct ftrace_event_call *call = &event_bprint; |
769b0441 FW |
1105 | struct ring_buffer_event *event; |
1106 | struct trace_array *tr = &global_trace; | |
1107 | struct trace_array_cpu *data; | |
48ead020 | 1108 | struct bprint_entry *entry; |
769b0441 | 1109 | unsigned long flags; |
3189cdb3 | 1110 | int disable; |
769b0441 FW |
1111 | int resched; |
1112 | int cpu, len = 0, size, pc; | |
1113 | ||
1114 | if (unlikely(tracing_selftest_running || tracing_disabled)) | |
1115 | return 0; | |
1116 | ||
1117 | /* Don't pollute graph traces with trace_vprintk internals */ | |
1118 | pause_graph_tracing(); | |
1119 | ||
1120 | pc = preempt_count(); | |
1121 | resched = ftrace_preempt_disable(); | |
1122 | cpu = raw_smp_processor_id(); | |
1123 | data = tr->data[cpu]; | |
1124 | ||
3189cdb3 SR |
1125 | disable = atomic_inc_return(&data->disabled); |
1126 | if (unlikely(disable != 1)) | |
769b0441 FW |
1127 | goto out; |
1128 | ||
80370cb7 SR |
1129 | /* Lockdep uses trace_printk for lock tracing */ |
1130 | local_irq_save(flags); | |
1131 | __raw_spin_lock(&trace_buf_lock); | |
769b0441 FW |
1132 | len = vbin_printf(trace_buf, TRACE_BUF_SIZE, fmt, args); |
1133 | ||
1134 | if (len > TRACE_BUF_SIZE || len < 0) | |
1135 | goto out_unlock; | |
1136 | ||
1137 | size = sizeof(*entry) + sizeof(u32) * len; | |
48ead020 | 1138 | event = trace_buffer_lock_reserve(tr, TRACE_BPRINT, size, flags, pc); |
769b0441 FW |
1139 | if (!event) |
1140 | goto out_unlock; | |
1141 | entry = ring_buffer_event_data(event); | |
1142 | entry->ip = ip; | |
769b0441 FW |
1143 | entry->fmt = fmt; |
1144 | ||
1145 | memcpy(entry->buf, trace_buf, sizeof(u32) * len); | |
eb02ce01 TZ |
1146 | if (!filter_check_discard(call, entry, tr->buffer, event)) |
1147 | ring_buffer_unlock_commit(tr->buffer, event); | |
769b0441 FW |
1148 | |
1149 | out_unlock: | |
80370cb7 SR |
1150 | __raw_spin_unlock(&trace_buf_lock); |
1151 | local_irq_restore(flags); | |
769b0441 FW |
1152 | |
1153 | out: | |
3189cdb3 | 1154 | atomic_dec_return(&data->disabled); |
769b0441 FW |
1155 | ftrace_preempt_enable(resched); |
1156 | unpause_graph_tracing(); | |
1157 | ||
1158 | return len; | |
1159 | } | |
48ead020 FW |
1160 | EXPORT_SYMBOL_GPL(trace_vbprintk); |
1161 | ||
40ce74f1 | 1162 | int trace_vprintk(unsigned long ip, const char *fmt, va_list args) |
48ead020 FW |
1163 | { |
1164 | static raw_spinlock_t trace_buf_lock = __RAW_SPIN_LOCK_UNLOCKED; | |
1165 | static char trace_buf[TRACE_BUF_SIZE]; | |
1166 | ||
e1112b4d | 1167 | struct ftrace_event_call *call = &event_print; |
48ead020 FW |
1168 | struct ring_buffer_event *event; |
1169 | struct trace_array *tr = &global_trace; | |
1170 | struct trace_array_cpu *data; | |
1171 | int cpu, len = 0, size, pc; | |
1172 | struct print_entry *entry; | |
1173 | unsigned long irq_flags; | |
3189cdb3 | 1174 | int disable; |
48ead020 FW |
1175 | |
1176 | if (tracing_disabled || tracing_selftest_running) | |
1177 | return 0; | |
1178 | ||
1179 | pc = preempt_count(); | |
1180 | preempt_disable_notrace(); | |
1181 | cpu = raw_smp_processor_id(); | |
1182 | data = tr->data[cpu]; | |
1183 | ||
3189cdb3 SR |
1184 | disable = atomic_inc_return(&data->disabled); |
1185 | if (unlikely(disable != 1)) | |
48ead020 FW |
1186 | goto out; |
1187 | ||
1188 | pause_graph_tracing(); | |
1189 | raw_local_irq_save(irq_flags); | |
1190 | __raw_spin_lock(&trace_buf_lock); | |
1191 | len = vsnprintf(trace_buf, TRACE_BUF_SIZE, fmt, args); | |
1192 | ||
1193 | len = min(len, TRACE_BUF_SIZE-1); | |
1194 | trace_buf[len] = 0; | |
1195 | ||
1196 | size = sizeof(*entry) + len + 1; | |
1197 | event = trace_buffer_lock_reserve(tr, TRACE_PRINT, size, irq_flags, pc); | |
1198 | if (!event) | |
1199 | goto out_unlock; | |
1200 | entry = ring_buffer_event_data(event); | |
1201 | entry->ip = ip; | |
48ead020 FW |
1202 | |
1203 | memcpy(&entry->buf, trace_buf, len); | |
1204 | entry->buf[len] = 0; | |
eb02ce01 TZ |
1205 | if (!filter_check_discard(call, entry, tr->buffer, event)) |
1206 | ring_buffer_unlock_commit(tr->buffer, event); | |
48ead020 FW |
1207 | |
1208 | out_unlock: | |
1209 | __raw_spin_unlock(&trace_buf_lock); | |
1210 | raw_local_irq_restore(irq_flags); | |
1211 | unpause_graph_tracing(); | |
1212 | out: | |
3189cdb3 | 1213 | atomic_dec_return(&data->disabled); |
48ead020 FW |
1214 | preempt_enable_notrace(); |
1215 | ||
1216 | return len; | |
1217 | } | |
769b0441 FW |
1218 | EXPORT_SYMBOL_GPL(trace_vprintk); |
1219 | ||
bc0c38d1 SR |
1220 | enum trace_file_type { |
1221 | TRACE_FILE_LAT_FMT = 1, | |
12ef7d44 | 1222 | TRACE_FILE_ANNOTATE = 2, |
bc0c38d1 SR |
1223 | }; |
1224 | ||
e2ac8ef5 | 1225 | static void trace_iterator_increment(struct trace_iterator *iter) |
5a90f577 | 1226 | { |
d769041f SR |
1227 | /* Don't allow ftrace to trace into the ring buffers */ |
1228 | ftrace_disable_cpu(); | |
1229 | ||
5a90f577 | 1230 | iter->idx++; |
d769041f SR |
1231 | if (iter->buffer_iter[iter->cpu]) |
1232 | ring_buffer_read(iter->buffer_iter[iter->cpu], NULL); | |
1233 | ||
1234 | ftrace_enable_cpu(); | |
5a90f577 SR |
1235 | } |
1236 | ||
e309b41d | 1237 | static struct trace_entry * |
3928a8a2 | 1238 | peek_next_entry(struct trace_iterator *iter, int cpu, u64 *ts) |
dd0e545f | 1239 | { |
3928a8a2 SR |
1240 | struct ring_buffer_event *event; |
1241 | struct ring_buffer_iter *buf_iter = iter->buffer_iter[cpu]; | |
dd0e545f | 1242 | |
d769041f SR |
1243 | /* Don't allow ftrace to trace into the ring buffers */ |
1244 | ftrace_disable_cpu(); | |
1245 | ||
1246 | if (buf_iter) | |
1247 | event = ring_buffer_iter_peek(buf_iter, ts); | |
1248 | else | |
1249 | event = ring_buffer_peek(iter->tr->buffer, cpu, ts); | |
1250 | ||
1251 | ftrace_enable_cpu(); | |
1252 | ||
3928a8a2 | 1253 | return event ? ring_buffer_event_data(event) : NULL; |
dd0e545f | 1254 | } |
d769041f | 1255 | |
dd0e545f | 1256 | static struct trace_entry * |
3928a8a2 | 1257 | __find_next_entry(struct trace_iterator *iter, int *ent_cpu, u64 *ent_ts) |
bc0c38d1 | 1258 | { |
3928a8a2 | 1259 | struct ring_buffer *buffer = iter->tr->buffer; |
bc0c38d1 | 1260 | struct trace_entry *ent, *next = NULL; |
b04cc6b1 | 1261 | int cpu_file = iter->cpu_file; |
3928a8a2 | 1262 | u64 next_ts = 0, ts; |
bc0c38d1 SR |
1263 | int next_cpu = -1; |
1264 | int cpu; | |
1265 | ||
b04cc6b1 FW |
1266 | /* |
1267 | * If we are in a per_cpu trace file, don't bother by iterating over | |
1268 | * all cpu and peek directly. | |
1269 | */ | |
1270 | if (cpu_file > TRACE_PIPE_ALL_CPU) { | |
1271 | if (ring_buffer_empty_cpu(buffer, cpu_file)) | |
1272 | return NULL; | |
1273 | ent = peek_next_entry(iter, cpu_file, ent_ts); | |
1274 | if (ent_cpu) | |
1275 | *ent_cpu = cpu_file; | |
1276 | ||
1277 | return ent; | |
1278 | } | |
1279 | ||
ab46428c | 1280 | for_each_tracing_cpu(cpu) { |
dd0e545f | 1281 | |
3928a8a2 SR |
1282 | if (ring_buffer_empty_cpu(buffer, cpu)) |
1283 | continue; | |
dd0e545f | 1284 | |
3928a8a2 | 1285 | ent = peek_next_entry(iter, cpu, &ts); |
dd0e545f | 1286 | |
cdd31cd2 IM |
1287 | /* |
1288 | * Pick the entry with the smallest timestamp: | |
1289 | */ | |
3928a8a2 | 1290 | if (ent && (!next || ts < next_ts)) { |
bc0c38d1 SR |
1291 | next = ent; |
1292 | next_cpu = cpu; | |
3928a8a2 | 1293 | next_ts = ts; |
bc0c38d1 SR |
1294 | } |
1295 | } | |
1296 | ||
1297 | if (ent_cpu) | |
1298 | *ent_cpu = next_cpu; | |
1299 | ||
3928a8a2 SR |
1300 | if (ent_ts) |
1301 | *ent_ts = next_ts; | |
1302 | ||
bc0c38d1 SR |
1303 | return next; |
1304 | } | |
1305 | ||
dd0e545f | 1306 | /* Find the next real entry, without updating the iterator itself */ |
c4a8e8be FW |
1307 | struct trace_entry *trace_find_next_entry(struct trace_iterator *iter, |
1308 | int *ent_cpu, u64 *ent_ts) | |
bc0c38d1 | 1309 | { |
3928a8a2 | 1310 | return __find_next_entry(iter, ent_cpu, ent_ts); |
dd0e545f SR |
1311 | } |
1312 | ||
1313 | /* Find the next real entry, and increment the iterator to the next entry */ | |
1314 | static void *find_next_entry_inc(struct trace_iterator *iter) | |
1315 | { | |
3928a8a2 | 1316 | iter->ent = __find_next_entry(iter, &iter->cpu, &iter->ts); |
dd0e545f | 1317 | |
3928a8a2 | 1318 | if (iter->ent) |
e2ac8ef5 | 1319 | trace_iterator_increment(iter); |
dd0e545f | 1320 | |
3928a8a2 | 1321 | return iter->ent ? iter : NULL; |
b3806b43 | 1322 | } |
bc0c38d1 | 1323 | |
e309b41d | 1324 | static void trace_consume(struct trace_iterator *iter) |
b3806b43 | 1325 | { |
d769041f SR |
1326 | /* Don't allow ftrace to trace into the ring buffers */ |
1327 | ftrace_disable_cpu(); | |
3928a8a2 | 1328 | ring_buffer_consume(iter->tr->buffer, iter->cpu, &iter->ts); |
d769041f | 1329 | ftrace_enable_cpu(); |
bc0c38d1 SR |
1330 | } |
1331 | ||
e309b41d | 1332 | static void *s_next(struct seq_file *m, void *v, loff_t *pos) |
bc0c38d1 SR |
1333 | { |
1334 | struct trace_iterator *iter = m->private; | |
bc0c38d1 | 1335 | int i = (int)*pos; |
4e3c3333 | 1336 | void *ent; |
bc0c38d1 SR |
1337 | |
1338 | (*pos)++; | |
1339 | ||
1340 | /* can't go backwards */ | |
1341 | if (iter->idx > i) | |
1342 | return NULL; | |
1343 | ||
1344 | if (iter->idx < 0) | |
1345 | ent = find_next_entry_inc(iter); | |
1346 | else | |
1347 | ent = iter; | |
1348 | ||
1349 | while (ent && iter->idx < i) | |
1350 | ent = find_next_entry_inc(iter); | |
1351 | ||
1352 | iter->pos = *pos; | |
1353 | ||
bc0c38d1 SR |
1354 | return ent; |
1355 | } | |
1356 | ||
d7350c3f FW |
1357 | /* |
1358 | * No necessary locking here. The worst thing which can | |
1359 | * happen is loosing events consumed at the same time | |
1360 | * by a trace_pipe reader. | |
1361 | * Other than that, we don't risk to crash the ring buffer | |
1362 | * because it serializes the readers. | |
1363 | * | |
1364 | * The current tracer is copied to avoid a global locking | |
1365 | * all around. | |
1366 | */ | |
bc0c38d1 SR |
1367 | static void *s_start(struct seq_file *m, loff_t *pos) |
1368 | { | |
1369 | struct trace_iterator *iter = m->private; | |
d7350c3f | 1370 | static struct tracer *old_tracer; |
b04cc6b1 | 1371 | int cpu_file = iter->cpu_file; |
bc0c38d1 SR |
1372 | void *p = NULL; |
1373 | loff_t l = 0; | |
3928a8a2 | 1374 | int cpu; |
bc0c38d1 | 1375 | |
d7350c3f | 1376 | /* copy the tracer to avoid using a global lock all around */ |
bc0c38d1 | 1377 | mutex_lock(&trace_types_lock); |
d7350c3f FW |
1378 | if (unlikely(old_tracer != current_trace && current_trace)) { |
1379 | old_tracer = current_trace; | |
1380 | *iter->trace = *current_trace; | |
d15f57f2 | 1381 | } |
d7350c3f | 1382 | mutex_unlock(&trace_types_lock); |
bc0c38d1 SR |
1383 | |
1384 | atomic_inc(&trace_record_cmdline_disabled); | |
1385 | ||
bc0c38d1 SR |
1386 | if (*pos != iter->pos) { |
1387 | iter->ent = NULL; | |
1388 | iter->cpu = 0; | |
1389 | iter->idx = -1; | |
1390 | ||
d769041f SR |
1391 | ftrace_disable_cpu(); |
1392 | ||
b04cc6b1 FW |
1393 | if (cpu_file == TRACE_PIPE_ALL_CPU) { |
1394 | for_each_tracing_cpu(cpu) | |
1395 | ring_buffer_iter_reset(iter->buffer_iter[cpu]); | |
1396 | } else | |
1397 | ring_buffer_iter_reset(iter->buffer_iter[cpu_file]); | |
1398 | ||
bc0c38d1 | 1399 | |
d769041f SR |
1400 | ftrace_enable_cpu(); |
1401 | ||
bc0c38d1 SR |
1402 | for (p = iter; p && l < *pos; p = s_next(m, p, &l)) |
1403 | ; | |
1404 | ||
1405 | } else { | |
4c11d7ae | 1406 | l = *pos - 1; |
bc0c38d1 SR |
1407 | p = s_next(m, p, &l); |
1408 | } | |
1409 | ||
4f535968 | 1410 | trace_event_read_lock(); |
bc0c38d1 SR |
1411 | return p; |
1412 | } | |
1413 | ||
1414 | static void s_stop(struct seq_file *m, void *p) | |
1415 | { | |
bc0c38d1 | 1416 | atomic_dec(&trace_record_cmdline_disabled); |
4f535968 | 1417 | trace_event_read_unlock(); |
bc0c38d1 SR |
1418 | } |
1419 | ||
e309b41d | 1420 | static void print_lat_help_header(struct seq_file *m) |
bc0c38d1 | 1421 | { |
a6168353 ME |
1422 | seq_puts(m, "# _------=> CPU# \n"); |
1423 | seq_puts(m, "# / _-----=> irqs-off \n"); | |
1424 | seq_puts(m, "# | / _----=> need-resched \n"); | |
1425 | seq_puts(m, "# || / _---=> hardirq/softirq \n"); | |
1426 | seq_puts(m, "# ||| / _--=> preempt-depth \n"); | |
1427 | seq_puts(m, "# |||| / \n"); | |
1428 | seq_puts(m, "# ||||| delay \n"); | |
1429 | seq_puts(m, "# cmd pid ||||| time | caller \n"); | |
1430 | seq_puts(m, "# \\ / ||||| \\ | / \n"); | |
bc0c38d1 SR |
1431 | } |
1432 | ||
e309b41d | 1433 | static void print_func_help_header(struct seq_file *m) |
bc0c38d1 | 1434 | { |
a6168353 ME |
1435 | seq_puts(m, "# TASK-PID CPU# TIMESTAMP FUNCTION\n"); |
1436 | seq_puts(m, "# | | | | |\n"); | |
bc0c38d1 SR |
1437 | } |
1438 | ||
1439 | ||
e309b41d | 1440 | static void |
bc0c38d1 SR |
1441 | print_trace_header(struct seq_file *m, struct trace_iterator *iter) |
1442 | { | |
1443 | unsigned long sym_flags = (trace_flags & TRACE_ITER_SYM_MASK); | |
1444 | struct trace_array *tr = iter->tr; | |
1445 | struct trace_array_cpu *data = tr->data[tr->cpu]; | |
1446 | struct tracer *type = current_trace; | |
3928a8a2 SR |
1447 | unsigned long total; |
1448 | unsigned long entries; | |
bc0c38d1 SR |
1449 | const char *name = "preemption"; |
1450 | ||
1451 | if (type) | |
1452 | name = type->name; | |
1453 | ||
3928a8a2 SR |
1454 | entries = ring_buffer_entries(iter->tr->buffer); |
1455 | total = entries + | |
1456 | ring_buffer_overruns(iter->tr->buffer); | |
bc0c38d1 | 1457 | |
888b55dc | 1458 | seq_printf(m, "# %s latency trace v1.1.5 on %s\n", |
bc0c38d1 | 1459 | name, UTS_RELEASE); |
888b55dc | 1460 | seq_puts(m, "# -----------------------------------" |
bc0c38d1 | 1461 | "---------------------------------\n"); |
888b55dc | 1462 | seq_printf(m, "# latency: %lu us, #%lu/%lu, CPU#%d |" |
bc0c38d1 | 1463 | " (M:%s VP:%d, KP:%d, SP:%d HP:%d", |
57f50be1 | 1464 | nsecs_to_usecs(data->saved_latency), |
bc0c38d1 | 1465 | entries, |
4c11d7ae | 1466 | total, |
bc0c38d1 SR |
1467 | tr->cpu, |
1468 | #if defined(CONFIG_PREEMPT_NONE) | |
1469 | "server", | |
1470 | #elif defined(CONFIG_PREEMPT_VOLUNTARY) | |
1471 | "desktop", | |
b5c21b45 | 1472 | #elif defined(CONFIG_PREEMPT) |
bc0c38d1 SR |
1473 | "preempt", |
1474 | #else | |
1475 | "unknown", | |
1476 | #endif | |
1477 | /* These are reserved for later use */ | |
1478 | 0, 0, 0, 0); | |
1479 | #ifdef CONFIG_SMP | |
1480 | seq_printf(m, " #P:%d)\n", num_online_cpus()); | |
1481 | #else | |
1482 | seq_puts(m, ")\n"); | |
1483 | #endif | |
888b55dc KM |
1484 | seq_puts(m, "# -----------------\n"); |
1485 | seq_printf(m, "# | task: %.16s-%d " | |
bc0c38d1 SR |
1486 | "(uid:%d nice:%ld policy:%ld rt_prio:%ld)\n", |
1487 | data->comm, data->pid, data->uid, data->nice, | |
1488 | data->policy, data->rt_priority); | |
888b55dc | 1489 | seq_puts(m, "# -----------------\n"); |
bc0c38d1 SR |
1490 | |
1491 | if (data->critical_start) { | |
888b55dc | 1492 | seq_puts(m, "# => started at: "); |
214023c3 SR |
1493 | seq_print_ip_sym(&iter->seq, data->critical_start, sym_flags); |
1494 | trace_print_seq(m, &iter->seq); | |
888b55dc | 1495 | seq_puts(m, "\n# => ended at: "); |
214023c3 SR |
1496 | seq_print_ip_sym(&iter->seq, data->critical_end, sym_flags); |
1497 | trace_print_seq(m, &iter->seq); | |
888b55dc | 1498 | seq_puts(m, "#\n"); |
bc0c38d1 SR |
1499 | } |
1500 | ||
888b55dc | 1501 | seq_puts(m, "#\n"); |
bc0c38d1 SR |
1502 | } |
1503 | ||
a309720c SR |
1504 | static void test_cpu_buff_start(struct trace_iterator *iter) |
1505 | { | |
1506 | struct trace_seq *s = &iter->seq; | |
1507 | ||
12ef7d44 SR |
1508 | if (!(trace_flags & TRACE_ITER_ANNOTATE)) |
1509 | return; | |
1510 | ||
1511 | if (!(iter->iter_flags & TRACE_FILE_ANNOTATE)) | |
1512 | return; | |
1513 | ||
4462344e | 1514 | if (cpumask_test_cpu(iter->cpu, iter->started)) |
a309720c SR |
1515 | return; |
1516 | ||
4462344e | 1517 | cpumask_set_cpu(iter->cpu, iter->started); |
b0dfa978 FW |
1518 | |
1519 | /* Don't print started cpu buffer for the first entry of the trace */ | |
1520 | if (iter->idx > 1) | |
1521 | trace_seq_printf(s, "##### CPU %u buffer started ####\n", | |
1522 | iter->cpu); | |
a309720c SR |
1523 | } |
1524 | ||
2c4f035f | 1525 | static enum print_line_t print_trace_fmt(struct trace_iterator *iter) |
bc0c38d1 | 1526 | { |
214023c3 | 1527 | struct trace_seq *s = &iter->seq; |
bc0c38d1 | 1528 | unsigned long sym_flags = (trace_flags & TRACE_ITER_SYM_MASK); |
4e3c3333 | 1529 | struct trace_entry *entry; |
f633cef0 | 1530 | struct trace_event *event; |
bc0c38d1 | 1531 | |
4e3c3333 | 1532 | entry = iter->ent; |
dd0e545f | 1533 | |
a309720c SR |
1534 | test_cpu_buff_start(iter); |
1535 | ||
c4a8e8be | 1536 | event = ftrace_find_event(entry->type); |
bc0c38d1 | 1537 | |
c4a8e8be | 1538 | if (trace_flags & TRACE_ITER_CONTEXT_INFO) { |
27d48be8 SR |
1539 | if (iter->iter_flags & TRACE_FILE_LAT_FMT) { |
1540 | if (!trace_print_lat_context(iter)) | |
1541 | goto partial; | |
1542 | } else { | |
1543 | if (!trace_print_context(iter)) | |
1544 | goto partial; | |
1545 | } | |
c4a8e8be | 1546 | } |
bc0c38d1 | 1547 | |
268ccda0 | 1548 | if (event) |
d9793bd8 ACM |
1549 | return event->trace(iter, sym_flags); |
1550 | ||
1551 | if (!trace_seq_printf(s, "Unknown type %d\n", entry->type)) | |
1552 | goto partial; | |
02b67518 | 1553 | |
2c4f035f | 1554 | return TRACE_TYPE_HANDLED; |
d9793bd8 ACM |
1555 | partial: |
1556 | return TRACE_TYPE_PARTIAL_LINE; | |
bc0c38d1 SR |
1557 | } |
1558 | ||
2c4f035f | 1559 | static enum print_line_t print_raw_fmt(struct trace_iterator *iter) |
f9896bf3 IM |
1560 | { |
1561 | struct trace_seq *s = &iter->seq; | |
1562 | struct trace_entry *entry; | |
f633cef0 | 1563 | struct trace_event *event; |
f9896bf3 IM |
1564 | |
1565 | entry = iter->ent; | |
dd0e545f | 1566 | |
c4a8e8be | 1567 | if (trace_flags & TRACE_ITER_CONTEXT_INFO) { |
d9793bd8 ACM |
1568 | if (!trace_seq_printf(s, "%d %d %llu ", |
1569 | entry->pid, iter->cpu, iter->ts)) | |
1570 | goto partial; | |
c4a8e8be | 1571 | } |
f9896bf3 | 1572 | |
f633cef0 | 1573 | event = ftrace_find_event(entry->type); |
268ccda0 | 1574 | if (event) |
d9793bd8 ACM |
1575 | return event->raw(iter, 0); |
1576 | ||
1577 | if (!trace_seq_printf(s, "%d ?\n", entry->type)) | |
1578 | goto partial; | |
777e208d | 1579 | |
2c4f035f | 1580 | return TRACE_TYPE_HANDLED; |
d9793bd8 ACM |
1581 | partial: |
1582 | return TRACE_TYPE_PARTIAL_LINE; | |
f9896bf3 IM |
1583 | } |
1584 | ||
2c4f035f | 1585 | static enum print_line_t print_hex_fmt(struct trace_iterator *iter) |
5e3ca0ec IM |
1586 | { |
1587 | struct trace_seq *s = &iter->seq; | |
1588 | unsigned char newline = '\n'; | |
1589 | struct trace_entry *entry; | |
f633cef0 | 1590 | struct trace_event *event; |
5e3ca0ec IM |
1591 | |
1592 | entry = iter->ent; | |
dd0e545f | 1593 | |
c4a8e8be FW |
1594 | if (trace_flags & TRACE_ITER_CONTEXT_INFO) { |
1595 | SEQ_PUT_HEX_FIELD_RET(s, entry->pid); | |
1596 | SEQ_PUT_HEX_FIELD_RET(s, iter->cpu); | |
1597 | SEQ_PUT_HEX_FIELD_RET(s, iter->ts); | |
1598 | } | |
5e3ca0ec | 1599 | |
f633cef0 | 1600 | event = ftrace_find_event(entry->type); |
268ccda0 | 1601 | if (event) { |
ae7462b4 | 1602 | enum print_line_t ret = event->hex(iter, 0); |
d9793bd8 ACM |
1603 | if (ret != TRACE_TYPE_HANDLED) |
1604 | return ret; | |
1605 | } | |
7104f300 | 1606 | |
5e3ca0ec IM |
1607 | SEQ_PUT_FIELD_RET(s, newline); |
1608 | ||
2c4f035f | 1609 | return TRACE_TYPE_HANDLED; |
5e3ca0ec IM |
1610 | } |
1611 | ||
2c4f035f | 1612 | static enum print_line_t print_bin_fmt(struct trace_iterator *iter) |
cb0f12aa IM |
1613 | { |
1614 | struct trace_seq *s = &iter->seq; | |
1615 | struct trace_entry *entry; | |
f633cef0 | 1616 | struct trace_event *event; |
cb0f12aa IM |
1617 | |
1618 | entry = iter->ent; | |
dd0e545f | 1619 | |
c4a8e8be FW |
1620 | if (trace_flags & TRACE_ITER_CONTEXT_INFO) { |
1621 | SEQ_PUT_FIELD_RET(s, entry->pid); | |
1830b52d | 1622 | SEQ_PUT_FIELD_RET(s, iter->cpu); |
c4a8e8be FW |
1623 | SEQ_PUT_FIELD_RET(s, iter->ts); |
1624 | } | |
cb0f12aa | 1625 | |
f633cef0 | 1626 | event = ftrace_find_event(entry->type); |
268ccda0 | 1627 | return event ? event->binary(iter, 0) : TRACE_TYPE_HANDLED; |
cb0f12aa IM |
1628 | } |
1629 | ||
bc0c38d1 SR |
1630 | static int trace_empty(struct trace_iterator *iter) |
1631 | { | |
bc0c38d1 SR |
1632 | int cpu; |
1633 | ||
9aba60fe SR |
1634 | /* If we are looking at one CPU buffer, only check that one */ |
1635 | if (iter->cpu_file != TRACE_PIPE_ALL_CPU) { | |
1636 | cpu = iter->cpu_file; | |
1637 | if (iter->buffer_iter[cpu]) { | |
1638 | if (!ring_buffer_iter_empty(iter->buffer_iter[cpu])) | |
1639 | return 0; | |
1640 | } else { | |
1641 | if (!ring_buffer_empty_cpu(iter->tr->buffer, cpu)) | |
1642 | return 0; | |
1643 | } | |
1644 | return 1; | |
1645 | } | |
1646 | ||
ab46428c | 1647 | for_each_tracing_cpu(cpu) { |
d769041f SR |
1648 | if (iter->buffer_iter[cpu]) { |
1649 | if (!ring_buffer_iter_empty(iter->buffer_iter[cpu])) | |
1650 | return 0; | |
1651 | } else { | |
1652 | if (!ring_buffer_empty_cpu(iter->tr->buffer, cpu)) | |
1653 | return 0; | |
1654 | } | |
bc0c38d1 | 1655 | } |
d769041f | 1656 | |
797d3712 | 1657 | return 1; |
bc0c38d1 SR |
1658 | } |
1659 | ||
4f535968 | 1660 | /* Called with trace_event_read_lock() held. */ |
2c4f035f | 1661 | static enum print_line_t print_trace_line(struct trace_iterator *iter) |
f9896bf3 | 1662 | { |
2c4f035f FW |
1663 | enum print_line_t ret; |
1664 | ||
1665 | if (iter->trace && iter->trace->print_line) { | |
1666 | ret = iter->trace->print_line(iter); | |
1667 | if (ret != TRACE_TYPE_UNHANDLED) | |
1668 | return ret; | |
1669 | } | |
72829bc3 | 1670 | |
48ead020 FW |
1671 | if (iter->ent->type == TRACE_BPRINT && |
1672 | trace_flags & TRACE_ITER_PRINTK && | |
1673 | trace_flags & TRACE_ITER_PRINTK_MSGONLY) | |
5ef841f6 | 1674 | return trace_print_bprintk_msg_only(iter); |
48ead020 | 1675 | |
66896a85 FW |
1676 | if (iter->ent->type == TRACE_PRINT && |
1677 | trace_flags & TRACE_ITER_PRINTK && | |
1678 | trace_flags & TRACE_ITER_PRINTK_MSGONLY) | |
5ef841f6 | 1679 | return trace_print_printk_msg_only(iter); |
66896a85 | 1680 | |
cb0f12aa IM |
1681 | if (trace_flags & TRACE_ITER_BIN) |
1682 | return print_bin_fmt(iter); | |
1683 | ||
5e3ca0ec IM |
1684 | if (trace_flags & TRACE_ITER_HEX) |
1685 | return print_hex_fmt(iter); | |
1686 | ||
f9896bf3 IM |
1687 | if (trace_flags & TRACE_ITER_RAW) |
1688 | return print_raw_fmt(iter); | |
1689 | ||
f9896bf3 IM |
1690 | return print_trace_fmt(iter); |
1691 | } | |
1692 | ||
bc0c38d1 SR |
1693 | static int s_show(struct seq_file *m, void *v) |
1694 | { | |
1695 | struct trace_iterator *iter = v; | |
1696 | ||
1697 | if (iter->ent == NULL) { | |
1698 | if (iter->tr) { | |
1699 | seq_printf(m, "# tracer: %s\n", iter->trace->name); | |
1700 | seq_puts(m, "#\n"); | |
1701 | } | |
8bba1bf5 MM |
1702 | if (iter->trace && iter->trace->print_header) |
1703 | iter->trace->print_header(m); | |
1704 | else if (iter->iter_flags & TRACE_FILE_LAT_FMT) { | |
bc0c38d1 SR |
1705 | /* print nothing if the buffers are empty */ |
1706 | if (trace_empty(iter)) | |
1707 | return 0; | |
1708 | print_trace_header(m, iter); | |
1709 | if (!(trace_flags & TRACE_ITER_VERBOSE)) | |
1710 | print_lat_help_header(m); | |
1711 | } else { | |
1712 | if (!(trace_flags & TRACE_ITER_VERBOSE)) | |
1713 | print_func_help_header(m); | |
1714 | } | |
1715 | } else { | |
f9896bf3 | 1716 | print_trace_line(iter); |
214023c3 | 1717 | trace_print_seq(m, &iter->seq); |
bc0c38d1 SR |
1718 | } |
1719 | ||
1720 | return 0; | |
1721 | } | |
1722 | ||
1723 | static struct seq_operations tracer_seq_ops = { | |
4bf39a94 IM |
1724 | .start = s_start, |
1725 | .next = s_next, | |
1726 | .stop = s_stop, | |
1727 | .show = s_show, | |
bc0c38d1 SR |
1728 | }; |
1729 | ||
e309b41d | 1730 | static struct trace_iterator * |
85a2f9b4 | 1731 | __tracing_open(struct inode *inode, struct file *file) |
bc0c38d1 | 1732 | { |
b04cc6b1 | 1733 | long cpu_file = (long) inode->i_private; |
85a2f9b4 | 1734 | void *fail_ret = ERR_PTR(-ENOMEM); |
bc0c38d1 | 1735 | struct trace_iterator *iter; |
3928a8a2 | 1736 | struct seq_file *m; |
85a2f9b4 | 1737 | int cpu, ret; |
bc0c38d1 | 1738 | |
85a2f9b4 SR |
1739 | if (tracing_disabled) |
1740 | return ERR_PTR(-ENODEV); | |
60a11774 | 1741 | |
bc0c38d1 | 1742 | iter = kzalloc(sizeof(*iter), GFP_KERNEL); |
85a2f9b4 SR |
1743 | if (!iter) |
1744 | return ERR_PTR(-ENOMEM); | |
bc0c38d1 | 1745 | |
d7350c3f FW |
1746 | /* |
1747 | * We make a copy of the current tracer to avoid concurrent | |
1748 | * changes on it while we are reading. | |
1749 | */ | |
bc0c38d1 | 1750 | mutex_lock(&trace_types_lock); |
d7350c3f | 1751 | iter->trace = kzalloc(sizeof(*iter->trace), GFP_KERNEL); |
85a2f9b4 | 1752 | if (!iter->trace) |
d7350c3f | 1753 | goto fail; |
85a2f9b4 | 1754 | |
d7350c3f FW |
1755 | if (current_trace) |
1756 | *iter->trace = *current_trace; | |
1757 | ||
b0dfa978 FW |
1758 | if (!alloc_cpumask_var(&iter->started, GFP_KERNEL)) |
1759 | goto fail; | |
1760 | ||
1761 | cpumask_clear(iter->started); | |
1762 | ||
bc0c38d1 SR |
1763 | if (current_trace && current_trace->print_max) |
1764 | iter->tr = &max_tr; | |
1765 | else | |
b04cc6b1 | 1766 | iter->tr = &global_trace; |
bc0c38d1 | 1767 | iter->pos = -1; |
d7350c3f | 1768 | mutex_init(&iter->mutex); |
b04cc6b1 | 1769 | iter->cpu_file = cpu_file; |
bc0c38d1 | 1770 | |
8bba1bf5 MM |
1771 | /* Notify the tracer early; before we stop tracing. */ |
1772 | if (iter->trace && iter->trace->open) | |
a93751ca | 1773 | iter->trace->open(iter); |
8bba1bf5 | 1774 | |
12ef7d44 SR |
1775 | /* Annotate start of buffers if we had overruns */ |
1776 | if (ring_buffer_overruns(iter->tr->buffer)) | |
1777 | iter->iter_flags |= TRACE_FILE_ANNOTATE; | |
1778 | ||
b04cc6b1 FW |
1779 | if (iter->cpu_file == TRACE_PIPE_ALL_CPU) { |
1780 | for_each_tracing_cpu(cpu) { | |
12ef7d44 | 1781 | |
b04cc6b1 FW |
1782 | iter->buffer_iter[cpu] = |
1783 | ring_buffer_read_start(iter->tr->buffer, cpu); | |
b04cc6b1 FW |
1784 | } |
1785 | } else { | |
1786 | cpu = iter->cpu_file; | |
3928a8a2 | 1787 | iter->buffer_iter[cpu] = |
b04cc6b1 | 1788 | ring_buffer_read_start(iter->tr->buffer, cpu); |
3928a8a2 SR |
1789 | } |
1790 | ||
bc0c38d1 | 1791 | /* TODO stop tracer */ |
85a2f9b4 SR |
1792 | ret = seq_open(file, &tracer_seq_ops); |
1793 | if (ret < 0) { | |
1794 | fail_ret = ERR_PTR(ret); | |
3928a8a2 | 1795 | goto fail_buffer; |
85a2f9b4 | 1796 | } |
bc0c38d1 | 1797 | |
3928a8a2 SR |
1798 | m = file->private_data; |
1799 | m->private = iter; | |
bc0c38d1 | 1800 | |
3928a8a2 | 1801 | /* stop the trace while dumping */ |
9036990d | 1802 | tracing_stop(); |
3928a8a2 | 1803 | |
bc0c38d1 SR |
1804 | mutex_unlock(&trace_types_lock); |
1805 | ||
bc0c38d1 | 1806 | return iter; |
3928a8a2 SR |
1807 | |
1808 | fail_buffer: | |
1809 | for_each_tracing_cpu(cpu) { | |
1810 | if (iter->buffer_iter[cpu]) | |
1811 | ring_buffer_read_finish(iter->buffer_iter[cpu]); | |
1812 | } | |
b0dfa978 | 1813 | free_cpumask_var(iter->started); |
d7350c3f | 1814 | fail: |
3928a8a2 | 1815 | mutex_unlock(&trace_types_lock); |
d7350c3f | 1816 | kfree(iter->trace); |
0bb943c7 | 1817 | kfree(iter); |
3928a8a2 | 1818 | |
85a2f9b4 | 1819 | return fail_ret; |
bc0c38d1 SR |
1820 | } |
1821 | ||
1822 | int tracing_open_generic(struct inode *inode, struct file *filp) | |
1823 | { | |
60a11774 SR |
1824 | if (tracing_disabled) |
1825 | return -ENODEV; | |
1826 | ||
bc0c38d1 SR |
1827 | filp->private_data = inode->i_private; |
1828 | return 0; | |
1829 | } | |
1830 | ||
4fd27358 | 1831 | static int tracing_release(struct inode *inode, struct file *file) |
bc0c38d1 SR |
1832 | { |
1833 | struct seq_file *m = (struct seq_file *)file->private_data; | |
4acd4d00 | 1834 | struct trace_iterator *iter; |
3928a8a2 | 1835 | int cpu; |
bc0c38d1 | 1836 | |
4acd4d00 SR |
1837 | if (!(file->f_mode & FMODE_READ)) |
1838 | return 0; | |
1839 | ||
1840 | iter = m->private; | |
1841 | ||
bc0c38d1 | 1842 | mutex_lock(&trace_types_lock); |
3928a8a2 SR |
1843 | for_each_tracing_cpu(cpu) { |
1844 | if (iter->buffer_iter[cpu]) | |
1845 | ring_buffer_read_finish(iter->buffer_iter[cpu]); | |
1846 | } | |
1847 | ||
bc0c38d1 SR |
1848 | if (iter->trace && iter->trace->close) |
1849 | iter->trace->close(iter); | |
1850 | ||
1851 | /* reenable tracing if it was previously enabled */ | |
9036990d | 1852 | tracing_start(); |
bc0c38d1 SR |
1853 | mutex_unlock(&trace_types_lock); |
1854 | ||
1855 | seq_release(inode, file); | |
d7350c3f | 1856 | mutex_destroy(&iter->mutex); |
b0dfa978 | 1857 | free_cpumask_var(iter->started); |
d7350c3f | 1858 | kfree(iter->trace); |
bc0c38d1 SR |
1859 | kfree(iter); |
1860 | return 0; | |
1861 | } | |
1862 | ||
1863 | static int tracing_open(struct inode *inode, struct file *file) | |
1864 | { | |
85a2f9b4 SR |
1865 | struct trace_iterator *iter; |
1866 | int ret = 0; | |
bc0c38d1 | 1867 | |
4acd4d00 SR |
1868 | /* If this file was open for write, then erase contents */ |
1869 | if ((file->f_mode & FMODE_WRITE) && | |
8650ae32 | 1870 | (file->f_flags & O_TRUNC)) { |
4acd4d00 | 1871 | long cpu = (long) inode->i_private; |
bc0c38d1 | 1872 | |
4acd4d00 SR |
1873 | if (cpu == TRACE_PIPE_ALL_CPU) |
1874 | tracing_reset_online_cpus(&global_trace); | |
1875 | else | |
1876 | tracing_reset(&global_trace, cpu); | |
1877 | } | |
bc0c38d1 | 1878 | |
4acd4d00 SR |
1879 | if (file->f_mode & FMODE_READ) { |
1880 | iter = __tracing_open(inode, file); | |
1881 | if (IS_ERR(iter)) | |
1882 | ret = PTR_ERR(iter); | |
1883 | else if (trace_flags & TRACE_ITER_LATENCY_FMT) | |
1884 | iter->iter_flags |= TRACE_FILE_LAT_FMT; | |
1885 | } | |
bc0c38d1 SR |
1886 | return ret; |
1887 | } | |
1888 | ||
e309b41d | 1889 | static void * |
bc0c38d1 SR |
1890 | t_next(struct seq_file *m, void *v, loff_t *pos) |
1891 | { | |
f129e965 | 1892 | struct tracer *t = v; |
bc0c38d1 SR |
1893 | |
1894 | (*pos)++; | |
1895 | ||
1896 | if (t) | |
1897 | t = t->next; | |
1898 | ||
bc0c38d1 SR |
1899 | return t; |
1900 | } | |
1901 | ||
1902 | static void *t_start(struct seq_file *m, loff_t *pos) | |
1903 | { | |
f129e965 | 1904 | struct tracer *t; |
bc0c38d1 SR |
1905 | loff_t l = 0; |
1906 | ||
1907 | mutex_lock(&trace_types_lock); | |
f129e965 | 1908 | for (t = trace_types; t && l < *pos; t = t_next(m, t, &l)) |
bc0c38d1 SR |
1909 | ; |
1910 | ||
1911 | return t; | |
1912 | } | |
1913 | ||
1914 | static void t_stop(struct seq_file *m, void *p) | |
1915 | { | |
1916 | mutex_unlock(&trace_types_lock); | |
1917 | } | |
1918 | ||
1919 | static int t_show(struct seq_file *m, void *v) | |
1920 | { | |
1921 | struct tracer *t = v; | |
1922 | ||
1923 | if (!t) | |
1924 | return 0; | |
1925 | ||
1926 | seq_printf(m, "%s", t->name); | |
1927 | if (t->next) | |
1928 | seq_putc(m, ' '); | |
1929 | else | |
1930 | seq_putc(m, '\n'); | |
1931 | ||
1932 | return 0; | |
1933 | } | |
1934 | ||
1935 | static struct seq_operations show_traces_seq_ops = { | |
4bf39a94 IM |
1936 | .start = t_start, |
1937 | .next = t_next, | |
1938 | .stop = t_stop, | |
1939 | .show = t_show, | |
bc0c38d1 SR |
1940 | }; |
1941 | ||
1942 | static int show_traces_open(struct inode *inode, struct file *file) | |
1943 | { | |
60a11774 SR |
1944 | if (tracing_disabled) |
1945 | return -ENODEV; | |
1946 | ||
f129e965 | 1947 | return seq_open(file, &show_traces_seq_ops); |
bc0c38d1 SR |
1948 | } |
1949 | ||
4acd4d00 SR |
1950 | static ssize_t |
1951 | tracing_write_stub(struct file *filp, const char __user *ubuf, | |
1952 | size_t count, loff_t *ppos) | |
1953 | { | |
1954 | return count; | |
1955 | } | |
1956 | ||
5e2336a0 | 1957 | static const struct file_operations tracing_fops = { |
4bf39a94 IM |
1958 | .open = tracing_open, |
1959 | .read = seq_read, | |
4acd4d00 | 1960 | .write = tracing_write_stub, |
4bf39a94 IM |
1961 | .llseek = seq_lseek, |
1962 | .release = tracing_release, | |
bc0c38d1 SR |
1963 | }; |
1964 | ||
5e2336a0 | 1965 | static const struct file_operations show_traces_fops = { |
c7078de1 IM |
1966 | .open = show_traces_open, |
1967 | .read = seq_read, | |
1968 | .release = seq_release, | |
1969 | }; | |
1970 | ||
36dfe925 IM |
1971 | /* |
1972 | * Only trace on a CPU if the bitmask is set: | |
1973 | */ | |
9e01c1b7 | 1974 | static cpumask_var_t tracing_cpumask; |
36dfe925 IM |
1975 | |
1976 | /* | |
1977 | * The tracer itself will not take this lock, but still we want | |
1978 | * to provide a consistent cpumask to user-space: | |
1979 | */ | |
1980 | static DEFINE_MUTEX(tracing_cpumask_update_lock); | |
1981 | ||
1982 | /* | |
1983 | * Temporary storage for the character representation of the | |
1984 | * CPU bitmask (and one more byte for the newline): | |
1985 | */ | |
1986 | static char mask_str[NR_CPUS + 1]; | |
1987 | ||
c7078de1 IM |
1988 | static ssize_t |
1989 | tracing_cpumask_read(struct file *filp, char __user *ubuf, | |
1990 | size_t count, loff_t *ppos) | |
1991 | { | |
36dfe925 | 1992 | int len; |
c7078de1 IM |
1993 | |
1994 | mutex_lock(&tracing_cpumask_update_lock); | |
36dfe925 | 1995 | |
9e01c1b7 | 1996 | len = cpumask_scnprintf(mask_str, count, tracing_cpumask); |
36dfe925 IM |
1997 | if (count - len < 2) { |
1998 | count = -EINVAL; | |
1999 | goto out_err; | |
2000 | } | |
2001 | len += sprintf(mask_str + len, "\n"); | |
2002 | count = simple_read_from_buffer(ubuf, count, ppos, mask_str, NR_CPUS+1); | |
2003 | ||
2004 | out_err: | |
c7078de1 IM |
2005 | mutex_unlock(&tracing_cpumask_update_lock); |
2006 | ||
2007 | return count; | |
2008 | } | |
2009 | ||
2010 | static ssize_t | |
2011 | tracing_cpumask_write(struct file *filp, const char __user *ubuf, | |
2012 | size_t count, loff_t *ppos) | |
2013 | { | |
36dfe925 | 2014 | int err, cpu; |
9e01c1b7 RR |
2015 | cpumask_var_t tracing_cpumask_new; |
2016 | ||
2017 | if (!alloc_cpumask_var(&tracing_cpumask_new, GFP_KERNEL)) | |
2018 | return -ENOMEM; | |
c7078de1 | 2019 | |
9e01c1b7 | 2020 | err = cpumask_parse_user(ubuf, count, tracing_cpumask_new); |
c7078de1 | 2021 | if (err) |
36dfe925 IM |
2022 | goto err_unlock; |
2023 | ||
215368e8 LZ |
2024 | mutex_lock(&tracing_cpumask_update_lock); |
2025 | ||
a5e25883 | 2026 | local_irq_disable(); |
92205c23 | 2027 | __raw_spin_lock(&ftrace_max_lock); |
ab46428c | 2028 | for_each_tracing_cpu(cpu) { |
36dfe925 IM |
2029 | /* |
2030 | * Increase/decrease the disabled counter if we are | |
2031 | * about to flip a bit in the cpumask: | |
2032 | */ | |
9e01c1b7 RR |
2033 | if (cpumask_test_cpu(cpu, tracing_cpumask) && |
2034 | !cpumask_test_cpu(cpu, tracing_cpumask_new)) { | |
36dfe925 IM |
2035 | atomic_inc(&global_trace.data[cpu]->disabled); |
2036 | } | |
9e01c1b7 RR |
2037 | if (!cpumask_test_cpu(cpu, tracing_cpumask) && |
2038 | cpumask_test_cpu(cpu, tracing_cpumask_new)) { | |
36dfe925 IM |
2039 | atomic_dec(&global_trace.data[cpu]->disabled); |
2040 | } | |
2041 | } | |
92205c23 | 2042 | __raw_spin_unlock(&ftrace_max_lock); |
a5e25883 | 2043 | local_irq_enable(); |
36dfe925 | 2044 | |
9e01c1b7 | 2045 | cpumask_copy(tracing_cpumask, tracing_cpumask_new); |
36dfe925 IM |
2046 | |
2047 | mutex_unlock(&tracing_cpumask_update_lock); | |
9e01c1b7 | 2048 | free_cpumask_var(tracing_cpumask_new); |
c7078de1 IM |
2049 | |
2050 | return count; | |
36dfe925 IM |
2051 | |
2052 | err_unlock: | |
215368e8 | 2053 | free_cpumask_var(tracing_cpumask_new); |
36dfe925 IM |
2054 | |
2055 | return err; | |
c7078de1 IM |
2056 | } |
2057 | ||
5e2336a0 | 2058 | static const struct file_operations tracing_cpumask_fops = { |
c7078de1 IM |
2059 | .open = tracing_open_generic, |
2060 | .read = tracing_cpumask_read, | |
2061 | .write = tracing_cpumask_write, | |
bc0c38d1 SR |
2062 | }; |
2063 | ||
2064 | static ssize_t | |
ee6bce52 | 2065 | tracing_trace_options_read(struct file *filp, char __user *ubuf, |
bc0c38d1 SR |
2066 | size_t cnt, loff_t *ppos) |
2067 | { | |
d8e83d26 SR |
2068 | struct tracer_opt *trace_opts; |
2069 | u32 tracer_flags; | |
2070 | int len = 0; | |
bc0c38d1 SR |
2071 | char *buf; |
2072 | int r = 0; | |
d8e83d26 | 2073 | int i; |
adf9f195 | 2074 | |
bc0c38d1 | 2075 | |
c3706f00 | 2076 | /* calculate max size */ |
bc0c38d1 SR |
2077 | for (i = 0; trace_options[i]; i++) { |
2078 | len += strlen(trace_options[i]); | |
5c6a3ae1 | 2079 | len += 3; /* "no" and newline */ |
bc0c38d1 SR |
2080 | } |
2081 | ||
d8e83d26 SR |
2082 | mutex_lock(&trace_types_lock); |
2083 | tracer_flags = current_trace->flags->val; | |
2084 | trace_opts = current_trace->flags->opts; | |
2085 | ||
adf9f195 FW |
2086 | /* |
2087 | * Increase the size with names of options specific | |
2088 | * of the current tracer. | |
2089 | */ | |
2090 | for (i = 0; trace_opts[i].name; i++) { | |
2091 | len += strlen(trace_opts[i].name); | |
5c6a3ae1 | 2092 | len += 3; /* "no" and newline */ |
adf9f195 FW |
2093 | } |
2094 | ||
ff4e9da2 XG |
2095 | /* +1 for \0 */ |
2096 | buf = kmalloc(len + 1, GFP_KERNEL); | |
d8e83d26 SR |
2097 | if (!buf) { |
2098 | mutex_unlock(&trace_types_lock); | |
bc0c38d1 | 2099 | return -ENOMEM; |
d8e83d26 | 2100 | } |
bc0c38d1 SR |
2101 | |
2102 | for (i = 0; trace_options[i]; i++) { | |
2103 | if (trace_flags & (1 << i)) | |
5c6a3ae1 | 2104 | r += sprintf(buf + r, "%s\n", trace_options[i]); |
bc0c38d1 | 2105 | else |
5c6a3ae1 | 2106 | r += sprintf(buf + r, "no%s\n", trace_options[i]); |
bc0c38d1 SR |
2107 | } |
2108 | ||
adf9f195 FW |
2109 | for (i = 0; trace_opts[i].name; i++) { |
2110 | if (tracer_flags & trace_opts[i].bit) | |
5c6a3ae1 | 2111 | r += sprintf(buf + r, "%s\n", |
adf9f195 FW |
2112 | trace_opts[i].name); |
2113 | else | |
5c6a3ae1 | 2114 | r += sprintf(buf + r, "no%s\n", |
adf9f195 FW |
2115 | trace_opts[i].name); |
2116 | } | |
d8e83d26 | 2117 | mutex_unlock(&trace_types_lock); |
adf9f195 | 2118 | |
ff4e9da2 | 2119 | WARN_ON(r >= len + 1); |
bc0c38d1 | 2120 | |
36dfe925 | 2121 | r = simple_read_from_buffer(ubuf, cnt, ppos, buf, r); |
bc0c38d1 SR |
2122 | |
2123 | kfree(buf); | |
bc0c38d1 SR |
2124 | return r; |
2125 | } | |
2126 | ||
adf9f195 FW |
2127 | /* Try to assign a tracer specific option */ |
2128 | static int set_tracer_option(struct tracer *trace, char *cmp, int neg) | |
2129 | { | |
7770841e | 2130 | struct tracer_flags *tracer_flags = trace->flags; |
adf9f195 FW |
2131 | struct tracer_opt *opts = NULL; |
2132 | int ret = 0, i = 0; | |
2133 | int len; | |
2134 | ||
7770841e Z |
2135 | for (i = 0; tracer_flags->opts[i].name; i++) { |
2136 | opts = &tracer_flags->opts[i]; | |
adf9f195 FW |
2137 | len = strlen(opts->name); |
2138 | ||
2139 | if (strncmp(cmp, opts->name, len) == 0) { | |
7770841e | 2140 | ret = trace->set_flag(tracer_flags->val, |
adf9f195 FW |
2141 | opts->bit, !neg); |
2142 | break; | |
2143 | } | |
2144 | } | |
2145 | /* Not found */ | |
7770841e | 2146 | if (!tracer_flags->opts[i].name) |
adf9f195 FW |
2147 | return -EINVAL; |
2148 | ||
2149 | /* Refused to handle */ | |
2150 | if (ret) | |
2151 | return ret; | |
2152 | ||
2153 | if (neg) | |
7770841e | 2154 | tracer_flags->val &= ~opts->bit; |
adf9f195 | 2155 | else |
7770841e | 2156 | tracer_flags->val |= opts->bit; |
adf9f195 FW |
2157 | |
2158 | return 0; | |
2159 | } | |
2160 | ||
af4617bd SR |
2161 | static void set_tracer_flags(unsigned int mask, int enabled) |
2162 | { | |
2163 | /* do nothing if flag is already set */ | |
2164 | if (!!(trace_flags & mask) == !!enabled) | |
2165 | return; | |
2166 | ||
2167 | if (enabled) | |
2168 | trace_flags |= mask; | |
2169 | else | |
2170 | trace_flags &= ~mask; | |
af4617bd SR |
2171 | } |
2172 | ||
bc0c38d1 | 2173 | static ssize_t |
ee6bce52 | 2174 | tracing_trace_options_write(struct file *filp, const char __user *ubuf, |
bc0c38d1 SR |
2175 | size_t cnt, loff_t *ppos) |
2176 | { | |
2177 | char buf[64]; | |
2178 | char *cmp = buf; | |
2179 | int neg = 0; | |
adf9f195 | 2180 | int ret; |
bc0c38d1 SR |
2181 | int i; |
2182 | ||
cffae437 SR |
2183 | if (cnt >= sizeof(buf)) |
2184 | return -EINVAL; | |
bc0c38d1 SR |
2185 | |
2186 | if (copy_from_user(&buf, ubuf, cnt)) | |
2187 | return -EFAULT; | |
2188 | ||
2189 | buf[cnt] = 0; | |
2190 | ||
2191 | if (strncmp(buf, "no", 2) == 0) { | |
2192 | neg = 1; | |
2193 | cmp += 2; | |
2194 | } | |
2195 | ||
2196 | for (i = 0; trace_options[i]; i++) { | |
2197 | int len = strlen(trace_options[i]); | |
2198 | ||
2199 | if (strncmp(cmp, trace_options[i], len) == 0) { | |
af4617bd | 2200 | set_tracer_flags(1 << i, !neg); |
bc0c38d1 SR |
2201 | break; |
2202 | } | |
2203 | } | |
adf9f195 FW |
2204 | |
2205 | /* If no option could be set, test the specific tracer options */ | |
2206 | if (!trace_options[i]) { | |
d8e83d26 | 2207 | mutex_lock(&trace_types_lock); |
adf9f195 | 2208 | ret = set_tracer_option(current_trace, cmp, neg); |
d8e83d26 | 2209 | mutex_unlock(&trace_types_lock); |
adf9f195 FW |
2210 | if (ret) |
2211 | return ret; | |
2212 | } | |
bc0c38d1 SR |
2213 | |
2214 | filp->f_pos += cnt; | |
2215 | ||
2216 | return cnt; | |
2217 | } | |
2218 | ||
5e2336a0 | 2219 | static const struct file_operations tracing_iter_fops = { |
c7078de1 | 2220 | .open = tracing_open_generic, |
ee6bce52 SR |
2221 | .read = tracing_trace_options_read, |
2222 | .write = tracing_trace_options_write, | |
bc0c38d1 SR |
2223 | }; |
2224 | ||
7bd2f24c IM |
2225 | static const char readme_msg[] = |
2226 | "tracing mini-HOWTO:\n\n" | |
156f5a78 GL |
2227 | "# mount -t debugfs nodev /sys/kernel/debug\n\n" |
2228 | "# cat /sys/kernel/debug/tracing/available_tracers\n" | |
bc2b6871 | 2229 | "wakeup preemptirqsoff preemptoff irqsoff function sched_switch nop\n\n" |
156f5a78 | 2230 | "# cat /sys/kernel/debug/tracing/current_tracer\n" |
bc2b6871 | 2231 | "nop\n" |
156f5a78 GL |
2232 | "# echo sched_switch > /sys/kernel/debug/tracing/current_tracer\n" |
2233 | "# cat /sys/kernel/debug/tracing/current_tracer\n" | |
7bd2f24c | 2234 | "sched_switch\n" |
156f5a78 | 2235 | "# cat /sys/kernel/debug/tracing/trace_options\n" |
7bd2f24c | 2236 | "noprint-parent nosym-offset nosym-addr noverbose\n" |
156f5a78 GL |
2237 | "# echo print-parent > /sys/kernel/debug/tracing/trace_options\n" |
2238 | "# echo 1 > /sys/kernel/debug/tracing/tracing_enabled\n" | |
2239 | "# cat /sys/kernel/debug/tracing/trace > /tmp/trace.txt\n" | |
2240 | "# echo 0 > /sys/kernel/debug/tracing/tracing_enabled\n" | |
7bd2f24c IM |
2241 | ; |
2242 | ||
2243 | static ssize_t | |
2244 | tracing_readme_read(struct file *filp, char __user *ubuf, | |
2245 | size_t cnt, loff_t *ppos) | |
2246 | { | |
2247 | return simple_read_from_buffer(ubuf, cnt, ppos, | |
2248 | readme_msg, strlen(readme_msg)); | |
2249 | } | |
2250 | ||
5e2336a0 | 2251 | static const struct file_operations tracing_readme_fops = { |
c7078de1 IM |
2252 | .open = tracing_open_generic, |
2253 | .read = tracing_readme_read, | |
7bd2f24c IM |
2254 | }; |
2255 | ||
69abe6a5 AP |
2256 | static ssize_t |
2257 | tracing_saved_cmdlines_read(struct file *file, char __user *ubuf, | |
2258 | size_t cnt, loff_t *ppos) | |
2259 | { | |
2260 | char *buf_comm; | |
2261 | char *file_buf; | |
2262 | char *buf; | |
2263 | int len = 0; | |
2264 | int pid; | |
2265 | int i; | |
2266 | ||
2267 | file_buf = kmalloc(SAVED_CMDLINES*(16+TASK_COMM_LEN), GFP_KERNEL); | |
2268 | if (!file_buf) | |
2269 | return -ENOMEM; | |
2270 | ||
2271 | buf_comm = kmalloc(TASK_COMM_LEN, GFP_KERNEL); | |
2272 | if (!buf_comm) { | |
2273 | kfree(file_buf); | |
2274 | return -ENOMEM; | |
2275 | } | |
2276 | ||
2277 | buf = file_buf; | |
2278 | ||
2279 | for (i = 0; i < SAVED_CMDLINES; i++) { | |
2280 | int r; | |
2281 | ||
2282 | pid = map_cmdline_to_pid[i]; | |
2283 | if (pid == -1 || pid == NO_CMDLINE_MAP) | |
2284 | continue; | |
2285 | ||
2286 | trace_find_cmdline(pid, buf_comm); | |
2287 | r = sprintf(buf, "%d %s\n", pid, buf_comm); | |
2288 | buf += r; | |
2289 | len += r; | |
2290 | } | |
2291 | ||
2292 | len = simple_read_from_buffer(ubuf, cnt, ppos, | |
2293 | file_buf, len); | |
2294 | ||
2295 | kfree(file_buf); | |
2296 | kfree(buf_comm); | |
2297 | ||
2298 | return len; | |
2299 | } | |
2300 | ||
2301 | static const struct file_operations tracing_saved_cmdlines_fops = { | |
2302 | .open = tracing_open_generic, | |
2303 | .read = tracing_saved_cmdlines_read, | |
2304 | }; | |
2305 | ||
bc0c38d1 SR |
2306 | static ssize_t |
2307 | tracing_ctrl_read(struct file *filp, char __user *ubuf, | |
2308 | size_t cnt, loff_t *ppos) | |
2309 | { | |
bc0c38d1 SR |
2310 | char buf[64]; |
2311 | int r; | |
2312 | ||
9036990d | 2313 | r = sprintf(buf, "%u\n", tracer_enabled); |
4e3c3333 | 2314 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, r); |
bc0c38d1 SR |
2315 | } |
2316 | ||
2317 | static ssize_t | |
2318 | tracing_ctrl_write(struct file *filp, const char __user *ubuf, | |
2319 | size_t cnt, loff_t *ppos) | |
2320 | { | |
2321 | struct trace_array *tr = filp->private_data; | |
bc0c38d1 | 2322 | char buf[64]; |
5e39841c | 2323 | unsigned long val; |
c6caeeb1 | 2324 | int ret; |
bc0c38d1 | 2325 | |
cffae437 SR |
2326 | if (cnt >= sizeof(buf)) |
2327 | return -EINVAL; | |
bc0c38d1 SR |
2328 | |
2329 | if (copy_from_user(&buf, ubuf, cnt)) | |
2330 | return -EFAULT; | |
2331 | ||
2332 | buf[cnt] = 0; | |
2333 | ||
c6caeeb1 SR |
2334 | ret = strict_strtoul(buf, 10, &val); |
2335 | if (ret < 0) | |
2336 | return ret; | |
bc0c38d1 SR |
2337 | |
2338 | val = !!val; | |
2339 | ||
2340 | mutex_lock(&trace_types_lock); | |
9036990d SR |
2341 | if (tracer_enabled ^ val) { |
2342 | if (val) { | |
bc0c38d1 | 2343 | tracer_enabled = 1; |
9036990d SR |
2344 | if (current_trace->start) |
2345 | current_trace->start(tr); | |
2346 | tracing_start(); | |
2347 | } else { | |
bc0c38d1 | 2348 | tracer_enabled = 0; |
9036990d SR |
2349 | tracing_stop(); |
2350 | if (current_trace->stop) | |
2351 | current_trace->stop(tr); | |
2352 | } | |
bc0c38d1 SR |
2353 | } |
2354 | mutex_unlock(&trace_types_lock); | |
2355 | ||
2356 | filp->f_pos += cnt; | |
2357 | ||
2358 | return cnt; | |
2359 | } | |
2360 | ||
2361 | static ssize_t | |
2362 | tracing_set_trace_read(struct file *filp, char __user *ubuf, | |
2363 | size_t cnt, loff_t *ppos) | |
2364 | { | |
2365 | char buf[max_tracer_type_len+2]; | |
2366 | int r; | |
2367 | ||
2368 | mutex_lock(&trace_types_lock); | |
2369 | if (current_trace) | |
2370 | r = sprintf(buf, "%s\n", current_trace->name); | |
2371 | else | |
2372 | r = sprintf(buf, "\n"); | |
2373 | mutex_unlock(&trace_types_lock); | |
2374 | ||
4bf39a94 | 2375 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, r); |
bc0c38d1 SR |
2376 | } |
2377 | ||
b6f11df2 ACM |
2378 | int tracer_init(struct tracer *t, struct trace_array *tr) |
2379 | { | |
2380 | tracing_reset_online_cpus(tr); | |
2381 | return t->init(tr); | |
2382 | } | |
2383 | ||
73c5162a SR |
2384 | static int tracing_resize_ring_buffer(unsigned long size) |
2385 | { | |
2386 | int ret; | |
2387 | ||
2388 | /* | |
2389 | * If kernel or user changes the size of the ring buffer | |
a123c52b SR |
2390 | * we use the size that was given, and we can forget about |
2391 | * expanding it later. | |
73c5162a SR |
2392 | */ |
2393 | ring_buffer_expanded = 1; | |
2394 | ||
2395 | ret = ring_buffer_resize(global_trace.buffer, size); | |
2396 | if (ret < 0) | |
2397 | return ret; | |
2398 | ||
2399 | ret = ring_buffer_resize(max_tr.buffer, size); | |
2400 | if (ret < 0) { | |
2401 | int r; | |
2402 | ||
2403 | r = ring_buffer_resize(global_trace.buffer, | |
2404 | global_trace.entries); | |
2405 | if (r < 0) { | |
a123c52b SR |
2406 | /* |
2407 | * AARGH! We are left with different | |
2408 | * size max buffer!!!! | |
2409 | * The max buffer is our "snapshot" buffer. | |
2410 | * When a tracer needs a snapshot (one of the | |
2411 | * latency tracers), it swaps the max buffer | |
2412 | * with the saved snap shot. We succeeded to | |
2413 | * update the size of the main buffer, but failed to | |
2414 | * update the size of the max buffer. But when we tried | |
2415 | * to reset the main buffer to the original size, we | |
2416 | * failed there too. This is very unlikely to | |
2417 | * happen, but if it does, warn and kill all | |
2418 | * tracing. | |
2419 | */ | |
73c5162a SR |
2420 | WARN_ON(1); |
2421 | tracing_disabled = 1; | |
2422 | } | |
2423 | return ret; | |
2424 | } | |
2425 | ||
2426 | global_trace.entries = size; | |
2427 | ||
2428 | return ret; | |
2429 | } | |
2430 | ||
1852fcce SR |
2431 | /** |
2432 | * tracing_update_buffers - used by tracing facility to expand ring buffers | |
2433 | * | |
2434 | * To save on memory when the tracing is never used on a system with it | |
2435 | * configured in. The ring buffers are set to a minimum size. But once | |
2436 | * a user starts to use the tracing facility, then they need to grow | |
2437 | * to their default size. | |
2438 | * | |
2439 | * This function is to be called when a tracer is about to be used. | |
2440 | */ | |
2441 | int tracing_update_buffers(void) | |
2442 | { | |
2443 | int ret = 0; | |
2444 | ||
1027fcb2 | 2445 | mutex_lock(&trace_types_lock); |
1852fcce SR |
2446 | if (!ring_buffer_expanded) |
2447 | ret = tracing_resize_ring_buffer(trace_buf_size); | |
1027fcb2 | 2448 | mutex_unlock(&trace_types_lock); |
1852fcce SR |
2449 | |
2450 | return ret; | |
2451 | } | |
2452 | ||
577b785f SR |
2453 | struct trace_option_dentry; |
2454 | ||
2455 | static struct trace_option_dentry * | |
2456 | create_trace_option_files(struct tracer *tracer); | |
2457 | ||
2458 | static void | |
2459 | destroy_trace_option_files(struct trace_option_dentry *topts); | |
2460 | ||
b2821ae6 | 2461 | static int tracing_set_tracer(const char *buf) |
bc0c38d1 | 2462 | { |
577b785f | 2463 | static struct trace_option_dentry *topts; |
bc0c38d1 SR |
2464 | struct trace_array *tr = &global_trace; |
2465 | struct tracer *t; | |
d9e54076 | 2466 | int ret = 0; |
bc0c38d1 | 2467 | |
1027fcb2 SR |
2468 | mutex_lock(&trace_types_lock); |
2469 | ||
73c5162a SR |
2470 | if (!ring_buffer_expanded) { |
2471 | ret = tracing_resize_ring_buffer(trace_buf_size); | |
2472 | if (ret < 0) | |
59f586db | 2473 | goto out; |
73c5162a SR |
2474 | ret = 0; |
2475 | } | |
2476 | ||
bc0c38d1 SR |
2477 | for (t = trace_types; t; t = t->next) { |
2478 | if (strcmp(t->name, buf) == 0) | |
2479 | break; | |
2480 | } | |
c2931e05 FW |
2481 | if (!t) { |
2482 | ret = -EINVAL; | |
2483 | goto out; | |
2484 | } | |
2485 | if (t == current_trace) | |
bc0c38d1 SR |
2486 | goto out; |
2487 | ||
9f029e83 | 2488 | trace_branch_disable(); |
bc0c38d1 SR |
2489 | if (current_trace && current_trace->reset) |
2490 | current_trace->reset(tr); | |
2491 | ||
577b785f SR |
2492 | destroy_trace_option_files(topts); |
2493 | ||
bc0c38d1 | 2494 | current_trace = t; |
577b785f SR |
2495 | |
2496 | topts = create_trace_option_files(current_trace); | |
2497 | ||
1c80025a | 2498 | if (t->init) { |
b6f11df2 | 2499 | ret = tracer_init(t, tr); |
1c80025a FW |
2500 | if (ret) |
2501 | goto out; | |
2502 | } | |
bc0c38d1 | 2503 | |
9f029e83 | 2504 | trace_branch_enable(tr); |
bc0c38d1 SR |
2505 | out: |
2506 | mutex_unlock(&trace_types_lock); | |
2507 | ||
d9e54076 PZ |
2508 | return ret; |
2509 | } | |
2510 | ||
2511 | static ssize_t | |
2512 | tracing_set_trace_write(struct file *filp, const char __user *ubuf, | |
2513 | size_t cnt, loff_t *ppos) | |
2514 | { | |
2515 | char buf[max_tracer_type_len+1]; | |
2516 | int i; | |
2517 | size_t ret; | |
e6e7a65a FW |
2518 | int err; |
2519 | ||
2520 | ret = cnt; | |
d9e54076 PZ |
2521 | |
2522 | if (cnt > max_tracer_type_len) | |
2523 | cnt = max_tracer_type_len; | |
2524 | ||
2525 | if (copy_from_user(&buf, ubuf, cnt)) | |
2526 | return -EFAULT; | |
2527 | ||
2528 | buf[cnt] = 0; | |
2529 | ||
2530 | /* strip ending whitespace. */ | |
2531 | for (i = cnt - 1; i > 0 && isspace(buf[i]); i--) | |
2532 | buf[i] = 0; | |
2533 | ||
e6e7a65a FW |
2534 | err = tracing_set_tracer(buf); |
2535 | if (err) | |
2536 | return err; | |
d9e54076 | 2537 | |
e6e7a65a | 2538 | filp->f_pos += ret; |
bc0c38d1 | 2539 | |
c2931e05 | 2540 | return ret; |
bc0c38d1 SR |
2541 | } |
2542 | ||
2543 | static ssize_t | |
2544 | tracing_max_lat_read(struct file *filp, char __user *ubuf, | |
2545 | size_t cnt, loff_t *ppos) | |
2546 | { | |
2547 | unsigned long *ptr = filp->private_data; | |
2548 | char buf[64]; | |
2549 | int r; | |
2550 | ||
cffae437 | 2551 | r = snprintf(buf, sizeof(buf), "%ld\n", |
bc0c38d1 | 2552 | *ptr == (unsigned long)-1 ? -1 : nsecs_to_usecs(*ptr)); |
cffae437 SR |
2553 | if (r > sizeof(buf)) |
2554 | r = sizeof(buf); | |
4bf39a94 | 2555 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, r); |
bc0c38d1 SR |
2556 | } |
2557 | ||
2558 | static ssize_t | |
2559 | tracing_max_lat_write(struct file *filp, const char __user *ubuf, | |
2560 | size_t cnt, loff_t *ppos) | |
2561 | { | |
5e39841c | 2562 | unsigned long *ptr = filp->private_data; |
bc0c38d1 | 2563 | char buf[64]; |
5e39841c | 2564 | unsigned long val; |
c6caeeb1 | 2565 | int ret; |
bc0c38d1 | 2566 | |
cffae437 SR |
2567 | if (cnt >= sizeof(buf)) |
2568 | return -EINVAL; | |
bc0c38d1 SR |
2569 | |
2570 | if (copy_from_user(&buf, ubuf, cnt)) | |
2571 | return -EFAULT; | |
2572 | ||
2573 | buf[cnt] = 0; | |
2574 | ||
c6caeeb1 SR |
2575 | ret = strict_strtoul(buf, 10, &val); |
2576 | if (ret < 0) | |
2577 | return ret; | |
bc0c38d1 SR |
2578 | |
2579 | *ptr = val * 1000; | |
2580 | ||
2581 | return cnt; | |
2582 | } | |
2583 | ||
b3806b43 SR |
2584 | static int tracing_open_pipe(struct inode *inode, struct file *filp) |
2585 | { | |
b04cc6b1 | 2586 | long cpu_file = (long) inode->i_private; |
b3806b43 | 2587 | struct trace_iterator *iter; |
b04cc6b1 | 2588 | int ret = 0; |
b3806b43 SR |
2589 | |
2590 | if (tracing_disabled) | |
2591 | return -ENODEV; | |
2592 | ||
b04cc6b1 FW |
2593 | mutex_lock(&trace_types_lock); |
2594 | ||
2595 | /* We only allow one reader per cpu */ | |
2596 | if (cpu_file == TRACE_PIPE_ALL_CPU) { | |
2597 | if (!cpumask_empty(tracing_reader_cpumask)) { | |
2598 | ret = -EBUSY; | |
2599 | goto out; | |
2600 | } | |
2601 | cpumask_setall(tracing_reader_cpumask); | |
2602 | } else { | |
2603 | if (!cpumask_test_cpu(cpu_file, tracing_reader_cpumask)) | |
2604 | cpumask_set_cpu(cpu_file, tracing_reader_cpumask); | |
2605 | else { | |
2606 | ret = -EBUSY; | |
2607 | goto out; | |
2608 | } | |
b3806b43 SR |
2609 | } |
2610 | ||
2611 | /* create a buffer to store the information to pass to userspace */ | |
2612 | iter = kzalloc(sizeof(*iter), GFP_KERNEL); | |
b04cc6b1 FW |
2613 | if (!iter) { |
2614 | ret = -ENOMEM; | |
2615 | goto out; | |
2616 | } | |
b3806b43 | 2617 | |
d7350c3f FW |
2618 | /* |
2619 | * We make a copy of the current tracer to avoid concurrent | |
2620 | * changes on it while we are reading. | |
2621 | */ | |
2622 | iter->trace = kmalloc(sizeof(*iter->trace), GFP_KERNEL); | |
2623 | if (!iter->trace) { | |
2624 | ret = -ENOMEM; | |
2625 | goto fail; | |
2626 | } | |
2627 | if (current_trace) | |
2628 | *iter->trace = *current_trace; | |
2629 | ||
4462344e | 2630 | if (!alloc_cpumask_var(&iter->started, GFP_KERNEL)) { |
b04cc6b1 | 2631 | ret = -ENOMEM; |
d7350c3f | 2632 | goto fail; |
4462344e RR |
2633 | } |
2634 | ||
a309720c | 2635 | /* trace pipe does not show start of buffer */ |
4462344e | 2636 | cpumask_setall(iter->started); |
a309720c | 2637 | |
112f38a7 SR |
2638 | if (trace_flags & TRACE_ITER_LATENCY_FMT) |
2639 | iter->iter_flags |= TRACE_FILE_LAT_FMT; | |
2640 | ||
b04cc6b1 | 2641 | iter->cpu_file = cpu_file; |
b3806b43 | 2642 | iter->tr = &global_trace; |
d7350c3f | 2643 | mutex_init(&iter->mutex); |
b3806b43 SR |
2644 | filp->private_data = iter; |
2645 | ||
107bad8b SR |
2646 | if (iter->trace->pipe_open) |
2647 | iter->trace->pipe_open(iter); | |
107bad8b | 2648 | |
b04cc6b1 FW |
2649 | out: |
2650 | mutex_unlock(&trace_types_lock); | |
2651 | return ret; | |
d7350c3f FW |
2652 | |
2653 | fail: | |
2654 | kfree(iter->trace); | |
2655 | kfree(iter); | |
2656 | mutex_unlock(&trace_types_lock); | |
2657 | return ret; | |
b3806b43 SR |
2658 | } |
2659 | ||
2660 | static int tracing_release_pipe(struct inode *inode, struct file *file) | |
2661 | { | |
2662 | struct trace_iterator *iter = file->private_data; | |
2663 | ||
b04cc6b1 FW |
2664 | mutex_lock(&trace_types_lock); |
2665 | ||
2666 | if (iter->cpu_file == TRACE_PIPE_ALL_CPU) | |
2667 | cpumask_clear(tracing_reader_cpumask); | |
2668 | else | |
2669 | cpumask_clear_cpu(iter->cpu_file, tracing_reader_cpumask); | |
2670 | ||
2671 | mutex_unlock(&trace_types_lock); | |
2672 | ||
4462344e | 2673 | free_cpumask_var(iter->started); |
d7350c3f FW |
2674 | mutex_destroy(&iter->mutex); |
2675 | kfree(iter->trace); | |
b3806b43 | 2676 | kfree(iter); |
b3806b43 SR |
2677 | |
2678 | return 0; | |
2679 | } | |
2680 | ||
2a2cc8f7 SSP |
2681 | static unsigned int |
2682 | tracing_poll_pipe(struct file *filp, poll_table *poll_table) | |
2683 | { | |
2684 | struct trace_iterator *iter = filp->private_data; | |
2685 | ||
2686 | if (trace_flags & TRACE_ITER_BLOCK) { | |
2687 | /* | |
2688 | * Always select as readable when in blocking mode | |
2689 | */ | |
2690 | return POLLIN | POLLRDNORM; | |
afc2abc0 | 2691 | } else { |
2a2cc8f7 SSP |
2692 | if (!trace_empty(iter)) |
2693 | return POLLIN | POLLRDNORM; | |
2694 | poll_wait(filp, &trace_wait, poll_table); | |
2695 | if (!trace_empty(iter)) | |
2696 | return POLLIN | POLLRDNORM; | |
2697 | ||
2698 | return 0; | |
2699 | } | |
2700 | } | |
2701 | ||
6eaaa5d5 FW |
2702 | |
2703 | void default_wait_pipe(struct trace_iterator *iter) | |
2704 | { | |
2705 | DEFINE_WAIT(wait); | |
2706 | ||
2707 | prepare_to_wait(&trace_wait, &wait, TASK_INTERRUPTIBLE); | |
2708 | ||
2709 | if (trace_empty(iter)) | |
2710 | schedule(); | |
2711 | ||
2712 | finish_wait(&trace_wait, &wait); | |
2713 | } | |
2714 | ||
2715 | /* | |
2716 | * This is a make-shift waitqueue. | |
2717 | * A tracer might use this callback on some rare cases: | |
2718 | * | |
2719 | * 1) the current tracer might hold the runqueue lock when it wakes up | |
2720 | * a reader, hence a deadlock (sched, function, and function graph tracers) | |
2721 | * 2) the function tracers, trace all functions, we don't want | |
2722 | * the overhead of calling wake_up and friends | |
2723 | * (and tracing them too) | |
2724 | * | |
2725 | * Anyway, this is really very primitive wakeup. | |
2726 | */ | |
2727 | void poll_wait_pipe(struct trace_iterator *iter) | |
2728 | { | |
2729 | set_current_state(TASK_INTERRUPTIBLE); | |
2730 | /* sleep for 100 msecs, and try again. */ | |
2731 | schedule_timeout(HZ / 10); | |
2732 | } | |
2733 | ||
ff98781b EGM |
2734 | /* Must be called with trace_types_lock mutex held. */ |
2735 | static int tracing_wait_pipe(struct file *filp) | |
b3806b43 SR |
2736 | { |
2737 | struct trace_iterator *iter = filp->private_data; | |
b3806b43 | 2738 | |
b3806b43 | 2739 | while (trace_empty(iter)) { |
2dc8f095 | 2740 | |
107bad8b | 2741 | if ((filp->f_flags & O_NONBLOCK)) { |
ff98781b | 2742 | return -EAGAIN; |
107bad8b | 2743 | } |
2dc8f095 | 2744 | |
d7350c3f | 2745 | mutex_unlock(&iter->mutex); |
107bad8b | 2746 | |
6eaaa5d5 | 2747 | iter->trace->wait_pipe(iter); |
b3806b43 | 2748 | |
d7350c3f | 2749 | mutex_lock(&iter->mutex); |
107bad8b | 2750 | |
6eaaa5d5 | 2751 | if (signal_pending(current)) |
ff98781b | 2752 | return -EINTR; |
b3806b43 SR |
2753 | |
2754 | /* | |
2755 | * We block until we read something and tracing is disabled. | |
2756 | * We still block if tracing is disabled, but we have never | |
2757 | * read anything. This allows a user to cat this file, and | |
2758 | * then enable tracing. But after we have read something, | |
2759 | * we give an EOF when tracing is again disabled. | |
2760 | * | |
2761 | * iter->pos will be 0 if we haven't read anything. | |
2762 | */ | |
2763 | if (!tracer_enabled && iter->pos) | |
2764 | break; | |
b3806b43 SR |
2765 | } |
2766 | ||
ff98781b EGM |
2767 | return 1; |
2768 | } | |
2769 | ||
2770 | /* | |
2771 | * Consumer reader. | |
2772 | */ | |
2773 | static ssize_t | |
2774 | tracing_read_pipe(struct file *filp, char __user *ubuf, | |
2775 | size_t cnt, loff_t *ppos) | |
2776 | { | |
2777 | struct trace_iterator *iter = filp->private_data; | |
d7350c3f | 2778 | static struct tracer *old_tracer; |
ff98781b EGM |
2779 | ssize_t sret; |
2780 | ||
2781 | /* return any leftover data */ | |
2782 | sret = trace_seq_to_user(&iter->seq, ubuf, cnt); | |
2783 | if (sret != -EBUSY) | |
2784 | return sret; | |
2785 | ||
f9520750 | 2786 | trace_seq_init(&iter->seq); |
ff98781b | 2787 | |
d7350c3f | 2788 | /* copy the tracer to avoid using a global lock all around */ |
ff98781b | 2789 | mutex_lock(&trace_types_lock); |
d7350c3f FW |
2790 | if (unlikely(old_tracer != current_trace && current_trace)) { |
2791 | old_tracer = current_trace; | |
2792 | *iter->trace = *current_trace; | |
2793 | } | |
2794 | mutex_unlock(&trace_types_lock); | |
2795 | ||
2796 | /* | |
2797 | * Avoid more than one consumer on a single file descriptor | |
2798 | * This is just a matter of traces coherency, the ring buffer itself | |
2799 | * is protected. | |
2800 | */ | |
2801 | mutex_lock(&iter->mutex); | |
ff98781b EGM |
2802 | if (iter->trace->read) { |
2803 | sret = iter->trace->read(iter, filp, ubuf, cnt, ppos); | |
2804 | if (sret) | |
2805 | goto out; | |
2806 | } | |
2807 | ||
2808 | waitagain: | |
2809 | sret = tracing_wait_pipe(filp); | |
2810 | if (sret <= 0) | |
2811 | goto out; | |
2812 | ||
b3806b43 | 2813 | /* stop when tracing is finished */ |
ff98781b EGM |
2814 | if (trace_empty(iter)) { |
2815 | sret = 0; | |
107bad8b | 2816 | goto out; |
ff98781b | 2817 | } |
b3806b43 SR |
2818 | |
2819 | if (cnt >= PAGE_SIZE) | |
2820 | cnt = PAGE_SIZE - 1; | |
2821 | ||
53d0aa77 | 2822 | /* reset all but tr, trace, and overruns */ |
53d0aa77 SR |
2823 | memset(&iter->seq, 0, |
2824 | sizeof(struct trace_iterator) - | |
2825 | offsetof(struct trace_iterator, seq)); | |
4823ed7e | 2826 | iter->pos = -1; |
b3806b43 | 2827 | |
4f535968 | 2828 | trace_event_read_lock(); |
088b1e42 | 2829 | while (find_next_entry_inc(iter) != NULL) { |
2c4f035f | 2830 | enum print_line_t ret; |
088b1e42 SR |
2831 | int len = iter->seq.len; |
2832 | ||
f9896bf3 | 2833 | ret = print_trace_line(iter); |
2c4f035f | 2834 | if (ret == TRACE_TYPE_PARTIAL_LINE) { |
088b1e42 SR |
2835 | /* don't print partial lines */ |
2836 | iter->seq.len = len; | |
b3806b43 | 2837 | break; |
088b1e42 | 2838 | } |
b91facc3 FW |
2839 | if (ret != TRACE_TYPE_NO_CONSUME) |
2840 | trace_consume(iter); | |
b3806b43 SR |
2841 | |
2842 | if (iter->seq.len >= cnt) | |
2843 | break; | |
b3806b43 | 2844 | } |
4f535968 | 2845 | trace_event_read_unlock(); |
b3806b43 | 2846 | |
b3806b43 | 2847 | /* Now copy what we have to the user */ |
6c6c2796 PP |
2848 | sret = trace_seq_to_user(&iter->seq, ubuf, cnt); |
2849 | if (iter->seq.readpos >= iter->seq.len) | |
f9520750 | 2850 | trace_seq_init(&iter->seq); |
9ff4b974 PP |
2851 | |
2852 | /* | |
2853 | * If there was nothing to send to user, inspite of consuming trace | |
2854 | * entries, go back to wait for more entries. | |
2855 | */ | |
6c6c2796 | 2856 | if (sret == -EBUSY) |
9ff4b974 | 2857 | goto waitagain; |
b3806b43 | 2858 | |
107bad8b | 2859 | out: |
d7350c3f | 2860 | mutex_unlock(&iter->mutex); |
107bad8b | 2861 | |
6c6c2796 | 2862 | return sret; |
b3806b43 SR |
2863 | } |
2864 | ||
3c56819b EGM |
2865 | static void tracing_pipe_buf_release(struct pipe_inode_info *pipe, |
2866 | struct pipe_buffer *buf) | |
2867 | { | |
2868 | __free_page(buf->page); | |
2869 | } | |
2870 | ||
2871 | static void tracing_spd_release_pipe(struct splice_pipe_desc *spd, | |
2872 | unsigned int idx) | |
2873 | { | |
2874 | __free_page(spd->pages[idx]); | |
2875 | } | |
2876 | ||
2877 | static struct pipe_buf_operations tracing_pipe_buf_ops = { | |
34cd4998 SR |
2878 | .can_merge = 0, |
2879 | .map = generic_pipe_buf_map, | |
2880 | .unmap = generic_pipe_buf_unmap, | |
2881 | .confirm = generic_pipe_buf_confirm, | |
2882 | .release = tracing_pipe_buf_release, | |
2883 | .steal = generic_pipe_buf_steal, | |
2884 | .get = generic_pipe_buf_get, | |
3c56819b EGM |
2885 | }; |
2886 | ||
34cd4998 | 2887 | static size_t |
fa7c7f6e | 2888 | tracing_fill_pipe_page(size_t rem, struct trace_iterator *iter) |
34cd4998 SR |
2889 | { |
2890 | size_t count; | |
2891 | int ret; | |
2892 | ||
2893 | /* Seq buffer is page-sized, exactly what we need. */ | |
2894 | for (;;) { | |
2895 | count = iter->seq.len; | |
2896 | ret = print_trace_line(iter); | |
2897 | count = iter->seq.len - count; | |
2898 | if (rem < count) { | |
2899 | rem = 0; | |
2900 | iter->seq.len -= count; | |
2901 | break; | |
2902 | } | |
2903 | if (ret == TRACE_TYPE_PARTIAL_LINE) { | |
2904 | iter->seq.len -= count; | |
2905 | break; | |
2906 | } | |
2907 | ||
74e7ff8c LJ |
2908 | if (ret != TRACE_TYPE_NO_CONSUME) |
2909 | trace_consume(iter); | |
34cd4998 SR |
2910 | rem -= count; |
2911 | if (!find_next_entry_inc(iter)) { | |
2912 | rem = 0; | |
2913 | iter->ent = NULL; | |
2914 | break; | |
2915 | } | |
2916 | } | |
2917 | ||
2918 | return rem; | |
2919 | } | |
2920 | ||
3c56819b EGM |
2921 | static ssize_t tracing_splice_read_pipe(struct file *filp, |
2922 | loff_t *ppos, | |
2923 | struct pipe_inode_info *pipe, | |
2924 | size_t len, | |
2925 | unsigned int flags) | |
2926 | { | |
2927 | struct page *pages[PIPE_BUFFERS]; | |
2928 | struct partial_page partial[PIPE_BUFFERS]; | |
2929 | struct trace_iterator *iter = filp->private_data; | |
2930 | struct splice_pipe_desc spd = { | |
34cd4998 SR |
2931 | .pages = pages, |
2932 | .partial = partial, | |
2933 | .nr_pages = 0, /* This gets updated below. */ | |
2934 | .flags = flags, | |
2935 | .ops = &tracing_pipe_buf_ops, | |
2936 | .spd_release = tracing_spd_release_pipe, | |
3c56819b | 2937 | }; |
d7350c3f | 2938 | static struct tracer *old_tracer; |
3c56819b | 2939 | ssize_t ret; |
34cd4998 | 2940 | size_t rem; |
3c56819b EGM |
2941 | unsigned int i; |
2942 | ||
d7350c3f | 2943 | /* copy the tracer to avoid using a global lock all around */ |
3c56819b | 2944 | mutex_lock(&trace_types_lock); |
d7350c3f FW |
2945 | if (unlikely(old_tracer != current_trace && current_trace)) { |
2946 | old_tracer = current_trace; | |
2947 | *iter->trace = *current_trace; | |
2948 | } | |
2949 | mutex_unlock(&trace_types_lock); | |
2950 | ||
2951 | mutex_lock(&iter->mutex); | |
3c56819b EGM |
2952 | |
2953 | if (iter->trace->splice_read) { | |
2954 | ret = iter->trace->splice_read(iter, filp, | |
2955 | ppos, pipe, len, flags); | |
2956 | if (ret) | |
34cd4998 | 2957 | goto out_err; |
3c56819b EGM |
2958 | } |
2959 | ||
2960 | ret = tracing_wait_pipe(filp); | |
2961 | if (ret <= 0) | |
34cd4998 | 2962 | goto out_err; |
3c56819b EGM |
2963 | |
2964 | if (!iter->ent && !find_next_entry_inc(iter)) { | |
2965 | ret = -EFAULT; | |
34cd4998 | 2966 | goto out_err; |
3c56819b EGM |
2967 | } |
2968 | ||
4f535968 LJ |
2969 | trace_event_read_lock(); |
2970 | ||
3c56819b EGM |
2971 | /* Fill as many pages as possible. */ |
2972 | for (i = 0, rem = len; i < PIPE_BUFFERS && rem; i++) { | |
2973 | pages[i] = alloc_page(GFP_KERNEL); | |
34cd4998 SR |
2974 | if (!pages[i]) |
2975 | break; | |
3c56819b | 2976 | |
fa7c7f6e | 2977 | rem = tracing_fill_pipe_page(rem, iter); |
3c56819b EGM |
2978 | |
2979 | /* Copy the data into the page, so we can start over. */ | |
2980 | ret = trace_seq_to_buffer(&iter->seq, | |
2981 | page_address(pages[i]), | |
2982 | iter->seq.len); | |
2983 | if (ret < 0) { | |
2984 | __free_page(pages[i]); | |
2985 | break; | |
2986 | } | |
2987 | partial[i].offset = 0; | |
2988 | partial[i].len = iter->seq.len; | |
2989 | ||
f9520750 | 2990 | trace_seq_init(&iter->seq); |
3c56819b EGM |
2991 | } |
2992 | ||
4f535968 | 2993 | trace_event_read_unlock(); |
d7350c3f | 2994 | mutex_unlock(&iter->mutex); |
3c56819b EGM |
2995 | |
2996 | spd.nr_pages = i; | |
2997 | ||
2998 | return splice_to_pipe(pipe, &spd); | |
2999 | ||
34cd4998 | 3000 | out_err: |
d7350c3f | 3001 | mutex_unlock(&iter->mutex); |
3c56819b EGM |
3002 | |
3003 | return ret; | |
3004 | } | |
3005 | ||
a98a3c3f SR |
3006 | static ssize_t |
3007 | tracing_entries_read(struct file *filp, char __user *ubuf, | |
3008 | size_t cnt, loff_t *ppos) | |
3009 | { | |
3010 | struct trace_array *tr = filp->private_data; | |
db526ca3 | 3011 | char buf[96]; |
a98a3c3f SR |
3012 | int r; |
3013 | ||
db526ca3 SR |
3014 | mutex_lock(&trace_types_lock); |
3015 | if (!ring_buffer_expanded) | |
3016 | r = sprintf(buf, "%lu (expanded: %lu)\n", | |
3017 | tr->entries >> 10, | |
3018 | trace_buf_size >> 10); | |
3019 | else | |
3020 | r = sprintf(buf, "%lu\n", tr->entries >> 10); | |
3021 | mutex_unlock(&trace_types_lock); | |
3022 | ||
a98a3c3f SR |
3023 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, r); |
3024 | } | |
3025 | ||
3026 | static ssize_t | |
3027 | tracing_entries_write(struct file *filp, const char __user *ubuf, | |
3028 | size_t cnt, loff_t *ppos) | |
3029 | { | |
3030 | unsigned long val; | |
3031 | char buf[64]; | |
bf5e6519 | 3032 | int ret, cpu; |
a98a3c3f | 3033 | |
cffae437 SR |
3034 | if (cnt >= sizeof(buf)) |
3035 | return -EINVAL; | |
a98a3c3f SR |
3036 | |
3037 | if (copy_from_user(&buf, ubuf, cnt)) | |
3038 | return -EFAULT; | |
3039 | ||
3040 | buf[cnt] = 0; | |
3041 | ||
c6caeeb1 SR |
3042 | ret = strict_strtoul(buf, 10, &val); |
3043 | if (ret < 0) | |
3044 | return ret; | |
a98a3c3f SR |
3045 | |
3046 | /* must have at least 1 entry */ | |
3047 | if (!val) | |
3048 | return -EINVAL; | |
3049 | ||
3050 | mutex_lock(&trace_types_lock); | |
3051 | ||
c76f0694 | 3052 | tracing_stop(); |
a98a3c3f | 3053 | |
bf5e6519 SR |
3054 | /* disable all cpu buffers */ |
3055 | for_each_tracing_cpu(cpu) { | |
3056 | if (global_trace.data[cpu]) | |
3057 | atomic_inc(&global_trace.data[cpu]->disabled); | |
3058 | if (max_tr.data[cpu]) | |
3059 | atomic_inc(&max_tr.data[cpu]->disabled); | |
3060 | } | |
3061 | ||
1696b2b0 SR |
3062 | /* value is in KB */ |
3063 | val <<= 10; | |
3064 | ||
3928a8a2 | 3065 | if (val != global_trace.entries) { |
73c5162a | 3066 | ret = tracing_resize_ring_buffer(val); |
3928a8a2 SR |
3067 | if (ret < 0) { |
3068 | cnt = ret; | |
3eefae99 SR |
3069 | goto out; |
3070 | } | |
a98a3c3f SR |
3071 | } |
3072 | ||
3073 | filp->f_pos += cnt; | |
3074 | ||
19384c03 SR |
3075 | /* If check pages failed, return ENOMEM */ |
3076 | if (tracing_disabled) | |
3077 | cnt = -ENOMEM; | |
a98a3c3f | 3078 | out: |
bf5e6519 SR |
3079 | for_each_tracing_cpu(cpu) { |
3080 | if (global_trace.data[cpu]) | |
3081 | atomic_dec(&global_trace.data[cpu]->disabled); | |
3082 | if (max_tr.data[cpu]) | |
3083 | atomic_dec(&max_tr.data[cpu]->disabled); | |
3084 | } | |
3085 | ||
c76f0694 | 3086 | tracing_start(); |
a98a3c3f SR |
3087 | max_tr.entries = global_trace.entries; |
3088 | mutex_unlock(&trace_types_lock); | |
3089 | ||
3090 | return cnt; | |
3091 | } | |
3092 | ||
5bf9a1ee PP |
3093 | static int mark_printk(const char *fmt, ...) |
3094 | { | |
3095 | int ret; | |
3096 | va_list args; | |
3097 | va_start(args, fmt); | |
40ce74f1 | 3098 | ret = trace_vprintk(0, fmt, args); |
5bf9a1ee PP |
3099 | va_end(args); |
3100 | return ret; | |
3101 | } | |
3102 | ||
3103 | static ssize_t | |
3104 | tracing_mark_write(struct file *filp, const char __user *ubuf, | |
3105 | size_t cnt, loff_t *fpos) | |
3106 | { | |
3107 | char *buf; | |
3108 | char *end; | |
5bf9a1ee | 3109 | |
c76f0694 | 3110 | if (tracing_disabled) |
5bf9a1ee PP |
3111 | return -EINVAL; |
3112 | ||
3113 | if (cnt > TRACE_BUF_SIZE) | |
3114 | cnt = TRACE_BUF_SIZE; | |
3115 | ||
3116 | buf = kmalloc(cnt + 1, GFP_KERNEL); | |
3117 | if (buf == NULL) | |
3118 | return -ENOMEM; | |
3119 | ||
3120 | if (copy_from_user(buf, ubuf, cnt)) { | |
3121 | kfree(buf); | |
3122 | return -EFAULT; | |
3123 | } | |
3124 | ||
3125 | /* Cut from the first nil or newline. */ | |
3126 | buf[cnt] = '\0'; | |
3127 | end = strchr(buf, '\n'); | |
3128 | if (end) | |
3129 | *end = '\0'; | |
3130 | ||
3131 | cnt = mark_printk("%s\n", buf); | |
3132 | kfree(buf); | |
3133 | *fpos += cnt; | |
3134 | ||
3135 | return cnt; | |
3136 | } | |
3137 | ||
5079f326 Z |
3138 | static ssize_t tracing_clock_read(struct file *filp, char __user *ubuf, |
3139 | size_t cnt, loff_t *ppos) | |
3140 | { | |
3141 | char buf[64]; | |
3142 | int bufiter = 0; | |
3143 | int i; | |
3144 | ||
3145 | for (i = 0; i < ARRAY_SIZE(trace_clocks); i++) | |
3146 | bufiter += snprintf(buf + bufiter, sizeof(buf) - bufiter, | |
3147 | "%s%s%s%s", i ? " " : "", | |
3148 | i == trace_clock_id ? "[" : "", trace_clocks[i].name, | |
3149 | i == trace_clock_id ? "]" : ""); | |
3150 | bufiter += snprintf(buf + bufiter, sizeof(buf) - bufiter, "\n"); | |
3151 | ||
3152 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, bufiter); | |
3153 | } | |
3154 | ||
3155 | static ssize_t tracing_clock_write(struct file *filp, const char __user *ubuf, | |
3156 | size_t cnt, loff_t *fpos) | |
3157 | { | |
3158 | char buf[64]; | |
3159 | const char *clockstr; | |
3160 | int i; | |
3161 | ||
3162 | if (cnt >= sizeof(buf)) | |
3163 | return -EINVAL; | |
3164 | ||
3165 | if (copy_from_user(&buf, ubuf, cnt)) | |
3166 | return -EFAULT; | |
3167 | ||
3168 | buf[cnt] = 0; | |
3169 | ||
3170 | clockstr = strstrip(buf); | |
3171 | ||
3172 | for (i = 0; i < ARRAY_SIZE(trace_clocks); i++) { | |
3173 | if (strcmp(trace_clocks[i].name, clockstr) == 0) | |
3174 | break; | |
3175 | } | |
3176 | if (i == ARRAY_SIZE(trace_clocks)) | |
3177 | return -EINVAL; | |
3178 | ||
3179 | trace_clock_id = i; | |
3180 | ||
3181 | mutex_lock(&trace_types_lock); | |
3182 | ||
3183 | ring_buffer_set_clock(global_trace.buffer, trace_clocks[i].func); | |
3184 | if (max_tr.buffer) | |
3185 | ring_buffer_set_clock(max_tr.buffer, trace_clocks[i].func); | |
3186 | ||
3187 | mutex_unlock(&trace_types_lock); | |
3188 | ||
3189 | *fpos += cnt; | |
3190 | ||
3191 | return cnt; | |
3192 | } | |
3193 | ||
5e2336a0 | 3194 | static const struct file_operations tracing_max_lat_fops = { |
4bf39a94 IM |
3195 | .open = tracing_open_generic, |
3196 | .read = tracing_max_lat_read, | |
3197 | .write = tracing_max_lat_write, | |
bc0c38d1 SR |
3198 | }; |
3199 | ||
5e2336a0 | 3200 | static const struct file_operations tracing_ctrl_fops = { |
4bf39a94 IM |
3201 | .open = tracing_open_generic, |
3202 | .read = tracing_ctrl_read, | |
3203 | .write = tracing_ctrl_write, | |
bc0c38d1 SR |
3204 | }; |
3205 | ||
5e2336a0 | 3206 | static const struct file_operations set_tracer_fops = { |
4bf39a94 IM |
3207 | .open = tracing_open_generic, |
3208 | .read = tracing_set_trace_read, | |
3209 | .write = tracing_set_trace_write, | |
bc0c38d1 SR |
3210 | }; |
3211 | ||
5e2336a0 | 3212 | static const struct file_operations tracing_pipe_fops = { |
4bf39a94 | 3213 | .open = tracing_open_pipe, |
2a2cc8f7 | 3214 | .poll = tracing_poll_pipe, |
4bf39a94 | 3215 | .read = tracing_read_pipe, |
3c56819b | 3216 | .splice_read = tracing_splice_read_pipe, |
4bf39a94 | 3217 | .release = tracing_release_pipe, |
b3806b43 SR |
3218 | }; |
3219 | ||
5e2336a0 | 3220 | static const struct file_operations tracing_entries_fops = { |
a98a3c3f SR |
3221 | .open = tracing_open_generic, |
3222 | .read = tracing_entries_read, | |
3223 | .write = tracing_entries_write, | |
3224 | }; | |
3225 | ||
5e2336a0 | 3226 | static const struct file_operations tracing_mark_fops = { |
43a15386 | 3227 | .open = tracing_open_generic, |
5bf9a1ee PP |
3228 | .write = tracing_mark_write, |
3229 | }; | |
3230 | ||
5079f326 Z |
3231 | static const struct file_operations trace_clock_fops = { |
3232 | .open = tracing_open_generic, | |
3233 | .read = tracing_clock_read, | |
3234 | .write = tracing_clock_write, | |
3235 | }; | |
3236 | ||
2cadf913 SR |
3237 | struct ftrace_buffer_info { |
3238 | struct trace_array *tr; | |
3239 | void *spare; | |
3240 | int cpu; | |
3241 | unsigned int read; | |
3242 | }; | |
3243 | ||
3244 | static int tracing_buffers_open(struct inode *inode, struct file *filp) | |
3245 | { | |
3246 | int cpu = (int)(long)inode->i_private; | |
3247 | struct ftrace_buffer_info *info; | |
3248 | ||
3249 | if (tracing_disabled) | |
3250 | return -ENODEV; | |
3251 | ||
3252 | info = kzalloc(sizeof(*info), GFP_KERNEL); | |
3253 | if (!info) | |
3254 | return -ENOMEM; | |
3255 | ||
3256 | info->tr = &global_trace; | |
3257 | info->cpu = cpu; | |
ddd538f3 | 3258 | info->spare = NULL; |
2cadf913 SR |
3259 | /* Force reading ring buffer for first read */ |
3260 | info->read = (unsigned int)-1; | |
2cadf913 SR |
3261 | |
3262 | filp->private_data = info; | |
3263 | ||
d1e7e02f | 3264 | return nonseekable_open(inode, filp); |
2cadf913 SR |
3265 | } |
3266 | ||
3267 | static ssize_t | |
3268 | tracing_buffers_read(struct file *filp, char __user *ubuf, | |
3269 | size_t count, loff_t *ppos) | |
3270 | { | |
3271 | struct ftrace_buffer_info *info = filp->private_data; | |
3272 | unsigned int pos; | |
3273 | ssize_t ret; | |
3274 | size_t size; | |
3275 | ||
2dc5d12b SR |
3276 | if (!count) |
3277 | return 0; | |
3278 | ||
ddd538f3 LJ |
3279 | if (!info->spare) |
3280 | info->spare = ring_buffer_alloc_read_page(info->tr->buffer); | |
3281 | if (!info->spare) | |
3282 | return -ENOMEM; | |
3283 | ||
2cadf913 SR |
3284 | /* Do we have previous read data to read? */ |
3285 | if (info->read < PAGE_SIZE) | |
3286 | goto read; | |
3287 | ||
3288 | info->read = 0; | |
3289 | ||
3290 | ret = ring_buffer_read_page(info->tr->buffer, | |
3291 | &info->spare, | |
3292 | count, | |
3293 | info->cpu, 0); | |
3294 | if (ret < 0) | |
3295 | return 0; | |
3296 | ||
3297 | pos = ring_buffer_page_len(info->spare); | |
3298 | ||
3299 | if (pos < PAGE_SIZE) | |
3300 | memset(info->spare + pos, 0, PAGE_SIZE - pos); | |
3301 | ||
3302 | read: | |
3303 | size = PAGE_SIZE - info->read; | |
3304 | if (size > count) | |
3305 | size = count; | |
3306 | ||
3307 | ret = copy_to_user(ubuf, info->spare + info->read, size); | |
2dc5d12b | 3308 | if (ret == size) |
2cadf913 | 3309 | return -EFAULT; |
2dc5d12b SR |
3310 | size -= ret; |
3311 | ||
2cadf913 SR |
3312 | *ppos += size; |
3313 | info->read += size; | |
3314 | ||
3315 | return size; | |
3316 | } | |
3317 | ||
3318 | static int tracing_buffers_release(struct inode *inode, struct file *file) | |
3319 | { | |
3320 | struct ftrace_buffer_info *info = file->private_data; | |
3321 | ||
ddd538f3 LJ |
3322 | if (info->spare) |
3323 | ring_buffer_free_read_page(info->tr->buffer, info->spare); | |
2cadf913 SR |
3324 | kfree(info); |
3325 | ||
3326 | return 0; | |
3327 | } | |
3328 | ||
3329 | struct buffer_ref { | |
3330 | struct ring_buffer *buffer; | |
3331 | void *page; | |
3332 | int ref; | |
3333 | }; | |
3334 | ||
3335 | static void buffer_pipe_buf_release(struct pipe_inode_info *pipe, | |
3336 | struct pipe_buffer *buf) | |
3337 | { | |
3338 | struct buffer_ref *ref = (struct buffer_ref *)buf->private; | |
3339 | ||
3340 | if (--ref->ref) | |
3341 | return; | |
3342 | ||
3343 | ring_buffer_free_read_page(ref->buffer, ref->page); | |
3344 | kfree(ref); | |
3345 | buf->private = 0; | |
3346 | } | |
3347 | ||
3348 | static int buffer_pipe_buf_steal(struct pipe_inode_info *pipe, | |
3349 | struct pipe_buffer *buf) | |
3350 | { | |
3351 | return 1; | |
3352 | } | |
3353 | ||
3354 | static void buffer_pipe_buf_get(struct pipe_inode_info *pipe, | |
3355 | struct pipe_buffer *buf) | |
3356 | { | |
3357 | struct buffer_ref *ref = (struct buffer_ref *)buf->private; | |
3358 | ||
3359 | ref->ref++; | |
3360 | } | |
3361 | ||
3362 | /* Pipe buffer operations for a buffer. */ | |
3363 | static struct pipe_buf_operations buffer_pipe_buf_ops = { | |
3364 | .can_merge = 0, | |
3365 | .map = generic_pipe_buf_map, | |
3366 | .unmap = generic_pipe_buf_unmap, | |
3367 | .confirm = generic_pipe_buf_confirm, | |
3368 | .release = buffer_pipe_buf_release, | |
3369 | .steal = buffer_pipe_buf_steal, | |
3370 | .get = buffer_pipe_buf_get, | |
3371 | }; | |
3372 | ||
3373 | /* | |
3374 | * Callback from splice_to_pipe(), if we need to release some pages | |
3375 | * at the end of the spd in case we error'ed out in filling the pipe. | |
3376 | */ | |
3377 | static void buffer_spd_release(struct splice_pipe_desc *spd, unsigned int i) | |
3378 | { | |
3379 | struct buffer_ref *ref = | |
3380 | (struct buffer_ref *)spd->partial[i].private; | |
3381 | ||
3382 | if (--ref->ref) | |
3383 | return; | |
3384 | ||
3385 | ring_buffer_free_read_page(ref->buffer, ref->page); | |
3386 | kfree(ref); | |
3387 | spd->partial[i].private = 0; | |
3388 | } | |
3389 | ||
3390 | static ssize_t | |
3391 | tracing_buffers_splice_read(struct file *file, loff_t *ppos, | |
3392 | struct pipe_inode_info *pipe, size_t len, | |
3393 | unsigned int flags) | |
3394 | { | |
3395 | struct ftrace_buffer_info *info = file->private_data; | |
3396 | struct partial_page partial[PIPE_BUFFERS]; | |
3397 | struct page *pages[PIPE_BUFFERS]; | |
3398 | struct splice_pipe_desc spd = { | |
3399 | .pages = pages, | |
3400 | .partial = partial, | |
3401 | .flags = flags, | |
3402 | .ops = &buffer_pipe_buf_ops, | |
3403 | .spd_release = buffer_spd_release, | |
3404 | }; | |
3405 | struct buffer_ref *ref; | |
93459c6c | 3406 | int entries, size, i; |
2cadf913 SR |
3407 | size_t ret; |
3408 | ||
93cfb3c9 LJ |
3409 | if (*ppos & (PAGE_SIZE - 1)) { |
3410 | WARN_ONCE(1, "Ftrace: previous read must page-align\n"); | |
3411 | return -EINVAL; | |
3412 | } | |
3413 | ||
3414 | if (len & (PAGE_SIZE - 1)) { | |
3415 | WARN_ONCE(1, "Ftrace: splice_read should page-align\n"); | |
3416 | if (len < PAGE_SIZE) | |
3417 | return -EINVAL; | |
3418 | len &= PAGE_MASK; | |
3419 | } | |
3420 | ||
93459c6c SR |
3421 | entries = ring_buffer_entries_cpu(info->tr->buffer, info->cpu); |
3422 | ||
3423 | for (i = 0; i < PIPE_BUFFERS && len && entries; i++, len -= PAGE_SIZE) { | |
2cadf913 SR |
3424 | struct page *page; |
3425 | int r; | |
3426 | ||
3427 | ref = kzalloc(sizeof(*ref), GFP_KERNEL); | |
3428 | if (!ref) | |
3429 | break; | |
3430 | ||
7267fa68 | 3431 | ref->ref = 1; |
2cadf913 SR |
3432 | ref->buffer = info->tr->buffer; |
3433 | ref->page = ring_buffer_alloc_read_page(ref->buffer); | |
3434 | if (!ref->page) { | |
3435 | kfree(ref); | |
3436 | break; | |
3437 | } | |
3438 | ||
3439 | r = ring_buffer_read_page(ref->buffer, &ref->page, | |
f2957f1f | 3440 | len, info->cpu, 1); |
2cadf913 SR |
3441 | if (r < 0) { |
3442 | ring_buffer_free_read_page(ref->buffer, | |
3443 | ref->page); | |
3444 | kfree(ref); | |
3445 | break; | |
3446 | } | |
3447 | ||
3448 | /* | |
3449 | * zero out any left over data, this is going to | |
3450 | * user land. | |
3451 | */ | |
3452 | size = ring_buffer_page_len(ref->page); | |
3453 | if (size < PAGE_SIZE) | |
3454 | memset(ref->page + size, 0, PAGE_SIZE - size); | |
3455 | ||
3456 | page = virt_to_page(ref->page); | |
3457 | ||
3458 | spd.pages[i] = page; | |
3459 | spd.partial[i].len = PAGE_SIZE; | |
3460 | spd.partial[i].offset = 0; | |
3461 | spd.partial[i].private = (unsigned long)ref; | |
3462 | spd.nr_pages++; | |
93cfb3c9 | 3463 | *ppos += PAGE_SIZE; |
93459c6c SR |
3464 | |
3465 | entries = ring_buffer_entries_cpu(info->tr->buffer, info->cpu); | |
2cadf913 SR |
3466 | } |
3467 | ||
3468 | spd.nr_pages = i; | |
3469 | ||
3470 | /* did we read anything? */ | |
3471 | if (!spd.nr_pages) { | |
3472 | if (flags & SPLICE_F_NONBLOCK) | |
3473 | ret = -EAGAIN; | |
3474 | else | |
3475 | ret = 0; | |
3476 | /* TODO: block */ | |
3477 | return ret; | |
3478 | } | |
3479 | ||
3480 | ret = splice_to_pipe(pipe, &spd); | |
3481 | ||
3482 | return ret; | |
3483 | } | |
3484 | ||
3485 | static const struct file_operations tracing_buffers_fops = { | |
3486 | .open = tracing_buffers_open, | |
3487 | .read = tracing_buffers_read, | |
3488 | .release = tracing_buffers_release, | |
3489 | .splice_read = tracing_buffers_splice_read, | |
3490 | .llseek = no_llseek, | |
3491 | }; | |
3492 | ||
c8d77183 SR |
3493 | static ssize_t |
3494 | tracing_stats_read(struct file *filp, char __user *ubuf, | |
3495 | size_t count, loff_t *ppos) | |
3496 | { | |
3497 | unsigned long cpu = (unsigned long)filp->private_data; | |
3498 | struct trace_array *tr = &global_trace; | |
3499 | struct trace_seq *s; | |
3500 | unsigned long cnt; | |
3501 | ||
e4f2d10f | 3502 | s = kmalloc(sizeof(*s), GFP_KERNEL); |
c8d77183 SR |
3503 | if (!s) |
3504 | return ENOMEM; | |
3505 | ||
3506 | trace_seq_init(s); | |
3507 | ||
3508 | cnt = ring_buffer_entries_cpu(tr->buffer, cpu); | |
3509 | trace_seq_printf(s, "entries: %ld\n", cnt); | |
3510 | ||
3511 | cnt = ring_buffer_overrun_cpu(tr->buffer, cpu); | |
3512 | trace_seq_printf(s, "overrun: %ld\n", cnt); | |
3513 | ||
3514 | cnt = ring_buffer_commit_overrun_cpu(tr->buffer, cpu); | |
3515 | trace_seq_printf(s, "commit overrun: %ld\n", cnt); | |
3516 | ||
c8d77183 SR |
3517 | count = simple_read_from_buffer(ubuf, count, ppos, s->buffer, s->len); |
3518 | ||
3519 | kfree(s); | |
3520 | ||
3521 | return count; | |
3522 | } | |
3523 | ||
3524 | static const struct file_operations tracing_stats_fops = { | |
3525 | .open = tracing_open_generic, | |
3526 | .read = tracing_stats_read, | |
3527 | }; | |
3528 | ||
bc0c38d1 SR |
3529 | #ifdef CONFIG_DYNAMIC_FTRACE |
3530 | ||
b807c3d0 SR |
3531 | int __weak ftrace_arch_read_dyn_info(char *buf, int size) |
3532 | { | |
3533 | return 0; | |
3534 | } | |
3535 | ||
bc0c38d1 | 3536 | static ssize_t |
b807c3d0 | 3537 | tracing_read_dyn_info(struct file *filp, char __user *ubuf, |
bc0c38d1 SR |
3538 | size_t cnt, loff_t *ppos) |
3539 | { | |
a26a2a27 SR |
3540 | static char ftrace_dyn_info_buffer[1024]; |
3541 | static DEFINE_MUTEX(dyn_info_mutex); | |
bc0c38d1 | 3542 | unsigned long *p = filp->private_data; |
b807c3d0 | 3543 | char *buf = ftrace_dyn_info_buffer; |
a26a2a27 | 3544 | int size = ARRAY_SIZE(ftrace_dyn_info_buffer); |
bc0c38d1 SR |
3545 | int r; |
3546 | ||
b807c3d0 SR |
3547 | mutex_lock(&dyn_info_mutex); |
3548 | r = sprintf(buf, "%ld ", *p); | |
4bf39a94 | 3549 | |
a26a2a27 | 3550 | r += ftrace_arch_read_dyn_info(buf+r, (size-1)-r); |
b807c3d0 SR |
3551 | buf[r++] = '\n'; |
3552 | ||
3553 | r = simple_read_from_buffer(ubuf, cnt, ppos, buf, r); | |
3554 | ||
3555 | mutex_unlock(&dyn_info_mutex); | |
3556 | ||
3557 | return r; | |
bc0c38d1 SR |
3558 | } |
3559 | ||
5e2336a0 | 3560 | static const struct file_operations tracing_dyn_info_fops = { |
4bf39a94 | 3561 | .open = tracing_open_generic, |
b807c3d0 | 3562 | .read = tracing_read_dyn_info, |
bc0c38d1 SR |
3563 | }; |
3564 | #endif | |
3565 | ||
3566 | static struct dentry *d_tracer; | |
3567 | ||
3568 | struct dentry *tracing_init_dentry(void) | |
3569 | { | |
3570 | static int once; | |
3571 | ||
3572 | if (d_tracer) | |
3573 | return d_tracer; | |
3574 | ||
3e1f60b8 FW |
3575 | if (!debugfs_initialized()) |
3576 | return NULL; | |
3577 | ||
bc0c38d1 SR |
3578 | d_tracer = debugfs_create_dir("tracing", NULL); |
3579 | ||
3580 | if (!d_tracer && !once) { | |
3581 | once = 1; | |
3582 | pr_warning("Could not create debugfs directory 'tracing'\n"); | |
3583 | return NULL; | |
3584 | } | |
3585 | ||
3586 | return d_tracer; | |
3587 | } | |
3588 | ||
b04cc6b1 FW |
3589 | static struct dentry *d_percpu; |
3590 | ||
3591 | struct dentry *tracing_dentry_percpu(void) | |
3592 | { | |
3593 | static int once; | |
3594 | struct dentry *d_tracer; | |
3595 | ||
3596 | if (d_percpu) | |
3597 | return d_percpu; | |
3598 | ||
3599 | d_tracer = tracing_init_dentry(); | |
3600 | ||
3601 | if (!d_tracer) | |
3602 | return NULL; | |
3603 | ||
3604 | d_percpu = debugfs_create_dir("per_cpu", d_tracer); | |
3605 | ||
3606 | if (!d_percpu && !once) { | |
3607 | once = 1; | |
3608 | pr_warning("Could not create debugfs directory 'per_cpu'\n"); | |
3609 | return NULL; | |
3610 | } | |
3611 | ||
3612 | return d_percpu; | |
3613 | } | |
3614 | ||
3615 | static void tracing_init_debugfs_percpu(long cpu) | |
3616 | { | |
3617 | struct dentry *d_percpu = tracing_dentry_percpu(); | |
5452af66 | 3618 | struct dentry *d_cpu; |
8656e7a2 FW |
3619 | /* strlen(cpu) + MAX(log10(cpu)) + '\0' */ |
3620 | char cpu_dir[7]; | |
b04cc6b1 FW |
3621 | |
3622 | if (cpu > 999 || cpu < 0) | |
3623 | return; | |
3624 | ||
8656e7a2 FW |
3625 | sprintf(cpu_dir, "cpu%ld", cpu); |
3626 | d_cpu = debugfs_create_dir(cpu_dir, d_percpu); | |
3627 | if (!d_cpu) { | |
3628 | pr_warning("Could not create debugfs '%s' entry\n", cpu_dir); | |
3629 | return; | |
3630 | } | |
b04cc6b1 | 3631 | |
8656e7a2 | 3632 | /* per cpu trace_pipe */ |
5452af66 FW |
3633 | trace_create_file("trace_pipe", 0444, d_cpu, |
3634 | (void *) cpu, &tracing_pipe_fops); | |
b04cc6b1 FW |
3635 | |
3636 | /* per cpu trace */ | |
5452af66 FW |
3637 | trace_create_file("trace", 0644, d_cpu, |
3638 | (void *) cpu, &tracing_fops); | |
7f96f93f | 3639 | |
5452af66 FW |
3640 | trace_create_file("trace_pipe_raw", 0444, d_cpu, |
3641 | (void *) cpu, &tracing_buffers_fops); | |
7f96f93f | 3642 | |
c8d77183 SR |
3643 | trace_create_file("stats", 0444, d_cpu, |
3644 | (void *) cpu, &tracing_stats_fops); | |
b04cc6b1 FW |
3645 | } |
3646 | ||
60a11774 SR |
3647 | #ifdef CONFIG_FTRACE_SELFTEST |
3648 | /* Let selftest have access to static functions in this file */ | |
3649 | #include "trace_selftest.c" | |
3650 | #endif | |
3651 | ||
577b785f SR |
3652 | struct trace_option_dentry { |
3653 | struct tracer_opt *opt; | |
3654 | struct tracer_flags *flags; | |
3655 | struct dentry *entry; | |
3656 | }; | |
3657 | ||
3658 | static ssize_t | |
3659 | trace_options_read(struct file *filp, char __user *ubuf, size_t cnt, | |
3660 | loff_t *ppos) | |
3661 | { | |
3662 | struct trace_option_dentry *topt = filp->private_data; | |
3663 | char *buf; | |
3664 | ||
3665 | if (topt->flags->val & topt->opt->bit) | |
3666 | buf = "1\n"; | |
3667 | else | |
3668 | buf = "0\n"; | |
3669 | ||
3670 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, 2); | |
3671 | } | |
3672 | ||
3673 | static ssize_t | |
3674 | trace_options_write(struct file *filp, const char __user *ubuf, size_t cnt, | |
3675 | loff_t *ppos) | |
3676 | { | |
3677 | struct trace_option_dentry *topt = filp->private_data; | |
3678 | unsigned long val; | |
3679 | char buf[64]; | |
3680 | int ret; | |
3681 | ||
3682 | if (cnt >= sizeof(buf)) | |
3683 | return -EINVAL; | |
3684 | ||
3685 | if (copy_from_user(&buf, ubuf, cnt)) | |
3686 | return -EFAULT; | |
3687 | ||
3688 | buf[cnt] = 0; | |
3689 | ||
3690 | ret = strict_strtoul(buf, 10, &val); | |
3691 | if (ret < 0) | |
3692 | return ret; | |
3693 | ||
3694 | ret = 0; | |
3695 | switch (val) { | |
3696 | case 0: | |
3697 | /* do nothing if already cleared */ | |
3698 | if (!(topt->flags->val & topt->opt->bit)) | |
3699 | break; | |
3700 | ||
3701 | mutex_lock(&trace_types_lock); | |
3702 | if (current_trace->set_flag) | |
3703 | ret = current_trace->set_flag(topt->flags->val, | |
3704 | topt->opt->bit, 0); | |
3705 | mutex_unlock(&trace_types_lock); | |
3706 | if (ret) | |
3707 | return ret; | |
3708 | topt->flags->val &= ~topt->opt->bit; | |
3709 | break; | |
3710 | case 1: | |
3711 | /* do nothing if already set */ | |
3712 | if (topt->flags->val & topt->opt->bit) | |
3713 | break; | |
3714 | ||
3715 | mutex_lock(&trace_types_lock); | |
3716 | if (current_trace->set_flag) | |
3717 | ret = current_trace->set_flag(topt->flags->val, | |
3718 | topt->opt->bit, 1); | |
3719 | mutex_unlock(&trace_types_lock); | |
3720 | if (ret) | |
3721 | return ret; | |
3722 | topt->flags->val |= topt->opt->bit; | |
3723 | break; | |
3724 | ||
3725 | default: | |
3726 | return -EINVAL; | |
3727 | } | |
3728 | ||
3729 | *ppos += cnt; | |
3730 | ||
3731 | return cnt; | |
3732 | } | |
3733 | ||
3734 | ||
3735 | static const struct file_operations trace_options_fops = { | |
3736 | .open = tracing_open_generic, | |
3737 | .read = trace_options_read, | |
3738 | .write = trace_options_write, | |
3739 | }; | |
3740 | ||
a8259075 SR |
3741 | static ssize_t |
3742 | trace_options_core_read(struct file *filp, char __user *ubuf, size_t cnt, | |
3743 | loff_t *ppos) | |
3744 | { | |
3745 | long index = (long)filp->private_data; | |
3746 | char *buf; | |
3747 | ||
3748 | if (trace_flags & (1 << index)) | |
3749 | buf = "1\n"; | |
3750 | else | |
3751 | buf = "0\n"; | |
3752 | ||
3753 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, 2); | |
3754 | } | |
3755 | ||
3756 | static ssize_t | |
3757 | trace_options_core_write(struct file *filp, const char __user *ubuf, size_t cnt, | |
3758 | loff_t *ppos) | |
3759 | { | |
3760 | long index = (long)filp->private_data; | |
3761 | char buf[64]; | |
3762 | unsigned long val; | |
3763 | int ret; | |
3764 | ||
3765 | if (cnt >= sizeof(buf)) | |
3766 | return -EINVAL; | |
3767 | ||
3768 | if (copy_from_user(&buf, ubuf, cnt)) | |
3769 | return -EFAULT; | |
3770 | ||
3771 | buf[cnt] = 0; | |
3772 | ||
3773 | ret = strict_strtoul(buf, 10, &val); | |
3774 | if (ret < 0) | |
3775 | return ret; | |
3776 | ||
3777 | switch (val) { | |
3778 | case 0: | |
3779 | trace_flags &= ~(1 << index); | |
3780 | break; | |
3781 | case 1: | |
3782 | trace_flags |= 1 << index; | |
3783 | break; | |
3784 | ||
3785 | default: | |
3786 | return -EINVAL; | |
3787 | } | |
3788 | ||
3789 | *ppos += cnt; | |
3790 | ||
3791 | return cnt; | |
3792 | } | |
3793 | ||
a8259075 SR |
3794 | static const struct file_operations trace_options_core_fops = { |
3795 | .open = tracing_open_generic, | |
3796 | .read = trace_options_core_read, | |
3797 | .write = trace_options_core_write, | |
3798 | }; | |
3799 | ||
5452af66 FW |
3800 | struct dentry *trace_create_file(const char *name, |
3801 | mode_t mode, | |
3802 | struct dentry *parent, | |
3803 | void *data, | |
3804 | const struct file_operations *fops) | |
3805 | { | |
3806 | struct dentry *ret; | |
3807 | ||
3808 | ret = debugfs_create_file(name, mode, parent, data, fops); | |
3809 | if (!ret) | |
3810 | pr_warning("Could not create debugfs '%s' entry\n", name); | |
3811 | ||
3812 | return ret; | |
3813 | } | |
3814 | ||
3815 | ||
a8259075 SR |
3816 | static struct dentry *trace_options_init_dentry(void) |
3817 | { | |
3818 | struct dentry *d_tracer; | |
3819 | static struct dentry *t_options; | |
3820 | ||
3821 | if (t_options) | |
3822 | return t_options; | |
3823 | ||
3824 | d_tracer = tracing_init_dentry(); | |
3825 | if (!d_tracer) | |
3826 | return NULL; | |
3827 | ||
3828 | t_options = debugfs_create_dir("options", d_tracer); | |
3829 | if (!t_options) { | |
3830 | pr_warning("Could not create debugfs directory 'options'\n"); | |
3831 | return NULL; | |
3832 | } | |
3833 | ||
3834 | return t_options; | |
3835 | } | |
3836 | ||
577b785f SR |
3837 | static void |
3838 | create_trace_option_file(struct trace_option_dentry *topt, | |
3839 | struct tracer_flags *flags, | |
3840 | struct tracer_opt *opt) | |
3841 | { | |
3842 | struct dentry *t_options; | |
577b785f SR |
3843 | |
3844 | t_options = trace_options_init_dentry(); | |
3845 | if (!t_options) | |
3846 | return; | |
3847 | ||
3848 | topt->flags = flags; | |
3849 | topt->opt = opt; | |
3850 | ||
5452af66 | 3851 | topt->entry = trace_create_file(opt->name, 0644, t_options, topt, |
577b785f SR |
3852 | &trace_options_fops); |
3853 | ||
577b785f SR |
3854 | } |
3855 | ||
3856 | static struct trace_option_dentry * | |
3857 | create_trace_option_files(struct tracer *tracer) | |
3858 | { | |
3859 | struct trace_option_dentry *topts; | |
3860 | struct tracer_flags *flags; | |
3861 | struct tracer_opt *opts; | |
3862 | int cnt; | |
3863 | ||
3864 | if (!tracer) | |
3865 | return NULL; | |
3866 | ||
3867 | flags = tracer->flags; | |
3868 | ||
3869 | if (!flags || !flags->opts) | |
3870 | return NULL; | |
3871 | ||
3872 | opts = flags->opts; | |
3873 | ||
3874 | for (cnt = 0; opts[cnt].name; cnt++) | |
3875 | ; | |
3876 | ||
0cfe8245 | 3877 | topts = kcalloc(cnt + 1, sizeof(*topts), GFP_KERNEL); |
577b785f SR |
3878 | if (!topts) |
3879 | return NULL; | |
3880 | ||
3881 | for (cnt = 0; opts[cnt].name; cnt++) | |
3882 | create_trace_option_file(&topts[cnt], flags, | |
3883 | &opts[cnt]); | |
3884 | ||
3885 | return topts; | |
3886 | } | |
3887 | ||
3888 | static void | |
3889 | destroy_trace_option_files(struct trace_option_dentry *topts) | |
3890 | { | |
3891 | int cnt; | |
3892 | ||
3893 | if (!topts) | |
3894 | return; | |
3895 | ||
3896 | for (cnt = 0; topts[cnt].opt; cnt++) { | |
3897 | if (topts[cnt].entry) | |
3898 | debugfs_remove(topts[cnt].entry); | |
3899 | } | |
3900 | ||
3901 | kfree(topts); | |
3902 | } | |
3903 | ||
a8259075 SR |
3904 | static struct dentry * |
3905 | create_trace_option_core_file(const char *option, long index) | |
3906 | { | |
3907 | struct dentry *t_options; | |
a8259075 SR |
3908 | |
3909 | t_options = trace_options_init_dentry(); | |
3910 | if (!t_options) | |
3911 | return NULL; | |
3912 | ||
5452af66 | 3913 | return trace_create_file(option, 0644, t_options, (void *)index, |
a8259075 | 3914 | &trace_options_core_fops); |
a8259075 SR |
3915 | } |
3916 | ||
3917 | static __init void create_trace_options_dir(void) | |
3918 | { | |
3919 | struct dentry *t_options; | |
a8259075 SR |
3920 | int i; |
3921 | ||
3922 | t_options = trace_options_init_dentry(); | |
3923 | if (!t_options) | |
3924 | return; | |
3925 | ||
5452af66 FW |
3926 | for (i = 0; trace_options[i]; i++) |
3927 | create_trace_option_core_file(trace_options[i], i); | |
a8259075 SR |
3928 | } |
3929 | ||
b5ad384e | 3930 | static __init int tracer_init_debugfs(void) |
bc0c38d1 SR |
3931 | { |
3932 | struct dentry *d_tracer; | |
b04cc6b1 | 3933 | int cpu; |
bc0c38d1 SR |
3934 | |
3935 | d_tracer = tracing_init_dentry(); | |
3936 | ||
5452af66 FW |
3937 | trace_create_file("tracing_enabled", 0644, d_tracer, |
3938 | &global_trace, &tracing_ctrl_fops); | |
bc0c38d1 | 3939 | |
5452af66 FW |
3940 | trace_create_file("trace_options", 0644, d_tracer, |
3941 | NULL, &tracing_iter_fops); | |
bc0c38d1 | 3942 | |
5452af66 FW |
3943 | trace_create_file("tracing_cpumask", 0644, d_tracer, |
3944 | NULL, &tracing_cpumask_fops); | |
3945 | ||
3946 | trace_create_file("trace", 0644, d_tracer, | |
3947 | (void *) TRACE_PIPE_ALL_CPU, &tracing_fops); | |
a8259075 | 3948 | |
5452af66 FW |
3949 | trace_create_file("available_tracers", 0444, d_tracer, |
3950 | &global_trace, &show_traces_fops); | |
3951 | ||
339ae5d3 | 3952 | trace_create_file("current_tracer", 0644, d_tracer, |
5452af66 FW |
3953 | &global_trace, &set_tracer_fops); |
3954 | ||
3955 | trace_create_file("tracing_max_latency", 0644, d_tracer, | |
3956 | &tracing_max_latency, &tracing_max_lat_fops); | |
3957 | ||
3958 | trace_create_file("tracing_thresh", 0644, d_tracer, | |
3959 | &tracing_thresh, &tracing_max_lat_fops); | |
a8259075 | 3960 | |
339ae5d3 | 3961 | trace_create_file("README", 0444, d_tracer, |
5452af66 FW |
3962 | NULL, &tracing_readme_fops); |
3963 | ||
3964 | trace_create_file("trace_pipe", 0444, d_tracer, | |
b04cc6b1 | 3965 | (void *) TRACE_PIPE_ALL_CPU, &tracing_pipe_fops); |
5452af66 FW |
3966 | |
3967 | trace_create_file("buffer_size_kb", 0644, d_tracer, | |
3968 | &global_trace, &tracing_entries_fops); | |
3969 | ||
3970 | trace_create_file("trace_marker", 0220, d_tracer, | |
3971 | NULL, &tracing_mark_fops); | |
5bf9a1ee | 3972 | |
69abe6a5 AP |
3973 | trace_create_file("saved_cmdlines", 0444, d_tracer, |
3974 | NULL, &tracing_saved_cmdlines_fops); | |
5bf9a1ee | 3975 | |
5079f326 Z |
3976 | trace_create_file("trace_clock", 0644, d_tracer, NULL, |
3977 | &trace_clock_fops); | |
3978 | ||
bc0c38d1 | 3979 | #ifdef CONFIG_DYNAMIC_FTRACE |
5452af66 FW |
3980 | trace_create_file("dyn_ftrace_total_info", 0444, d_tracer, |
3981 | &ftrace_update_tot_cnt, &tracing_dyn_info_fops); | |
bc0c38d1 | 3982 | #endif |
d618b3e6 IM |
3983 | #ifdef CONFIG_SYSPROF_TRACER |
3984 | init_tracer_sysprof_debugfs(d_tracer); | |
3985 | #endif | |
b04cc6b1 | 3986 | |
5452af66 FW |
3987 | create_trace_options_dir(); |
3988 | ||
b04cc6b1 FW |
3989 | for_each_tracing_cpu(cpu) |
3990 | tracing_init_debugfs_percpu(cpu); | |
3991 | ||
b5ad384e | 3992 | return 0; |
bc0c38d1 SR |
3993 | } |
3994 | ||
3f5a54e3 SR |
3995 | static int trace_panic_handler(struct notifier_block *this, |
3996 | unsigned long event, void *unused) | |
3997 | { | |
944ac425 SR |
3998 | if (ftrace_dump_on_oops) |
3999 | ftrace_dump(); | |
3f5a54e3 SR |
4000 | return NOTIFY_OK; |
4001 | } | |
4002 | ||
4003 | static struct notifier_block trace_panic_notifier = { | |
4004 | .notifier_call = trace_panic_handler, | |
4005 | .next = NULL, | |
4006 | .priority = 150 /* priority: INT_MAX >= x >= 0 */ | |
4007 | }; | |
4008 | ||
4009 | static int trace_die_handler(struct notifier_block *self, | |
4010 | unsigned long val, | |
4011 | void *data) | |
4012 | { | |
4013 | switch (val) { | |
4014 | case DIE_OOPS: | |
944ac425 SR |
4015 | if (ftrace_dump_on_oops) |
4016 | ftrace_dump(); | |
3f5a54e3 SR |
4017 | break; |
4018 | default: | |
4019 | break; | |
4020 | } | |
4021 | return NOTIFY_OK; | |
4022 | } | |
4023 | ||
4024 | static struct notifier_block trace_die_notifier = { | |
4025 | .notifier_call = trace_die_handler, | |
4026 | .priority = 200 | |
4027 | }; | |
4028 | ||
4029 | /* | |
4030 | * printk is set to max of 1024, we really don't need it that big. | |
4031 | * Nothing should be printing 1000 characters anyway. | |
4032 | */ | |
4033 | #define TRACE_MAX_PRINT 1000 | |
4034 | ||
4035 | /* | |
4036 | * Define here KERN_TRACE so that we have one place to modify | |
4037 | * it if we decide to change what log level the ftrace dump | |
4038 | * should be at. | |
4039 | */ | |
428aee14 | 4040 | #define KERN_TRACE KERN_EMERG |
3f5a54e3 SR |
4041 | |
4042 | static void | |
4043 | trace_printk_seq(struct trace_seq *s) | |
4044 | { | |
4045 | /* Probably should print a warning here. */ | |
4046 | if (s->len >= 1000) | |
4047 | s->len = 1000; | |
4048 | ||
4049 | /* should be zero ended, but we are paranoid. */ | |
4050 | s->buffer[s->len] = 0; | |
4051 | ||
4052 | printk(KERN_TRACE "%s", s->buffer); | |
4053 | ||
f9520750 | 4054 | trace_seq_init(s); |
3f5a54e3 SR |
4055 | } |
4056 | ||
cf586b61 | 4057 | static void __ftrace_dump(bool disable_tracing) |
3f5a54e3 | 4058 | { |
cd891ae0 SR |
4059 | static raw_spinlock_t ftrace_dump_lock = |
4060 | (raw_spinlock_t)__RAW_SPIN_LOCK_UNLOCKED; | |
3f5a54e3 SR |
4061 | /* use static because iter can be a bit big for the stack */ |
4062 | static struct trace_iterator iter; | |
cf586b61 | 4063 | unsigned int old_userobj; |
3f5a54e3 | 4064 | static int dump_ran; |
d769041f SR |
4065 | unsigned long flags; |
4066 | int cnt = 0, cpu; | |
3f5a54e3 SR |
4067 | |
4068 | /* only one dump */ | |
cd891ae0 SR |
4069 | local_irq_save(flags); |
4070 | __raw_spin_lock(&ftrace_dump_lock); | |
3f5a54e3 SR |
4071 | if (dump_ran) |
4072 | goto out; | |
4073 | ||
4074 | dump_ran = 1; | |
4075 | ||
0ee6b6cf | 4076 | tracing_off(); |
cf586b61 FW |
4077 | |
4078 | if (disable_tracing) | |
4079 | ftrace_kill(); | |
3f5a54e3 | 4080 | |
d769041f SR |
4081 | for_each_tracing_cpu(cpu) { |
4082 | atomic_inc(&global_trace.data[cpu]->disabled); | |
4083 | } | |
4084 | ||
cf586b61 FW |
4085 | old_userobj = trace_flags & TRACE_ITER_SYM_USEROBJ; |
4086 | ||
b54d3de9 TE |
4087 | /* don't look at user memory in panic mode */ |
4088 | trace_flags &= ~TRACE_ITER_SYM_USEROBJ; | |
4089 | ||
3f5a54e3 SR |
4090 | printk(KERN_TRACE "Dumping ftrace buffer:\n"); |
4091 | ||
e543ad76 | 4092 | /* Simulate the iterator */ |
3f5a54e3 SR |
4093 | iter.tr = &global_trace; |
4094 | iter.trace = current_trace; | |
e543ad76 | 4095 | iter.cpu_file = TRACE_PIPE_ALL_CPU; |
3f5a54e3 SR |
4096 | |
4097 | /* | |
4098 | * We need to stop all tracing on all CPUS to read the | |
4099 | * the next buffer. This is a bit expensive, but is | |
4100 | * not done often. We fill all what we can read, | |
4101 | * and then release the locks again. | |
4102 | */ | |
4103 | ||
3f5a54e3 SR |
4104 | while (!trace_empty(&iter)) { |
4105 | ||
4106 | if (!cnt) | |
4107 | printk(KERN_TRACE "---------------------------------\n"); | |
4108 | ||
4109 | cnt++; | |
4110 | ||
4111 | /* reset all but tr, trace, and overruns */ | |
4112 | memset(&iter.seq, 0, | |
4113 | sizeof(struct trace_iterator) - | |
4114 | offsetof(struct trace_iterator, seq)); | |
4115 | iter.iter_flags |= TRACE_FILE_LAT_FMT; | |
4116 | iter.pos = -1; | |
4117 | ||
4118 | if (find_next_entry_inc(&iter) != NULL) { | |
74e7ff8c LJ |
4119 | int ret; |
4120 | ||
4121 | ret = print_trace_line(&iter); | |
4122 | if (ret != TRACE_TYPE_NO_CONSUME) | |
4123 | trace_consume(&iter); | |
3f5a54e3 SR |
4124 | } |
4125 | ||
4126 | trace_printk_seq(&iter.seq); | |
4127 | } | |
4128 | ||
4129 | if (!cnt) | |
4130 | printk(KERN_TRACE " (ftrace buffer empty)\n"); | |
4131 | else | |
4132 | printk(KERN_TRACE "---------------------------------\n"); | |
4133 | ||
cf586b61 FW |
4134 | /* Re-enable tracing if requested */ |
4135 | if (!disable_tracing) { | |
4136 | trace_flags |= old_userobj; | |
4137 | ||
4138 | for_each_tracing_cpu(cpu) { | |
4139 | atomic_dec(&global_trace.data[cpu]->disabled); | |
4140 | } | |
4141 | tracing_on(); | |
4142 | } | |
4143 | ||
3f5a54e3 | 4144 | out: |
cd891ae0 SR |
4145 | __raw_spin_unlock(&ftrace_dump_lock); |
4146 | local_irq_restore(flags); | |
3f5a54e3 SR |
4147 | } |
4148 | ||
cf586b61 FW |
4149 | /* By default: disable tracing after the dump */ |
4150 | void ftrace_dump(void) | |
4151 | { | |
4152 | __ftrace_dump(true); | |
4153 | } | |
4154 | ||
3928a8a2 | 4155 | __init static int tracer_alloc_buffers(void) |
bc0c38d1 | 4156 | { |
73c5162a | 4157 | int ring_buf_size; |
4c11d7ae | 4158 | int i; |
9e01c1b7 | 4159 | int ret = -ENOMEM; |
4c11d7ae | 4160 | |
9e01c1b7 RR |
4161 | if (!alloc_cpumask_var(&tracing_buffer_mask, GFP_KERNEL)) |
4162 | goto out; | |
4163 | ||
4164 | if (!alloc_cpumask_var(&tracing_cpumask, GFP_KERNEL)) | |
4165 | goto out_free_buffer_mask; | |
4c11d7ae | 4166 | |
b04cc6b1 FW |
4167 | if (!alloc_cpumask_var(&tracing_reader_cpumask, GFP_KERNEL)) |
4168 | goto out_free_tracing_cpumask; | |
4169 | ||
73c5162a SR |
4170 | /* To save memory, keep the ring buffer size to its minimum */ |
4171 | if (ring_buffer_expanded) | |
4172 | ring_buf_size = trace_buf_size; | |
4173 | else | |
4174 | ring_buf_size = 1; | |
4175 | ||
9e01c1b7 RR |
4176 | cpumask_copy(tracing_buffer_mask, cpu_possible_mask); |
4177 | cpumask_copy(tracing_cpumask, cpu_all_mask); | |
b04cc6b1 | 4178 | cpumask_clear(tracing_reader_cpumask); |
9e01c1b7 RR |
4179 | |
4180 | /* TODO: make the number of buffers hot pluggable with CPUS */ | |
73c5162a | 4181 | global_trace.buffer = ring_buffer_alloc(ring_buf_size, |
3928a8a2 SR |
4182 | TRACE_BUFFER_FLAGS); |
4183 | if (!global_trace.buffer) { | |
4184 | printk(KERN_ERR "tracer: failed to allocate ring buffer!\n"); | |
4185 | WARN_ON(1); | |
9e01c1b7 | 4186 | goto out_free_cpumask; |
4c11d7ae | 4187 | } |
3928a8a2 | 4188 | global_trace.entries = ring_buffer_size(global_trace.buffer); |
4c11d7ae | 4189 | |
9e01c1b7 | 4190 | |
4c11d7ae | 4191 | #ifdef CONFIG_TRACER_MAX_TRACE |
73c5162a | 4192 | max_tr.buffer = ring_buffer_alloc(ring_buf_size, |
3928a8a2 SR |
4193 | TRACE_BUFFER_FLAGS); |
4194 | if (!max_tr.buffer) { | |
4195 | printk(KERN_ERR "tracer: failed to allocate max ring buffer!\n"); | |
4196 | WARN_ON(1); | |
4197 | ring_buffer_free(global_trace.buffer); | |
9e01c1b7 | 4198 | goto out_free_cpumask; |
4c11d7ae | 4199 | } |
3928a8a2 SR |
4200 | max_tr.entries = ring_buffer_size(max_tr.buffer); |
4201 | WARN_ON(max_tr.entries != global_trace.entries); | |
a98a3c3f | 4202 | #endif |
ab46428c | 4203 | |
4c11d7ae | 4204 | /* Allocate the first page for all buffers */ |
ab46428c | 4205 | for_each_tracing_cpu(i) { |
566b0aaf | 4206 | global_trace.data[i] = &per_cpu(global_trace_cpu, i); |
bc0c38d1 | 4207 | max_tr.data[i] = &per_cpu(max_data, i); |
4c11d7ae | 4208 | } |
bc0c38d1 | 4209 | |
bc0c38d1 SR |
4210 | trace_init_cmdlines(); |
4211 | ||
43a15386 | 4212 | register_tracer(&nop_trace); |
79fb0768 | 4213 | current_trace = &nop_trace; |
b5ad384e FW |
4214 | #ifdef CONFIG_BOOT_TRACER |
4215 | register_tracer(&boot_tracer); | |
b5ad384e | 4216 | #endif |
60a11774 SR |
4217 | /* All seems OK, enable tracing */ |
4218 | tracing_disabled = 0; | |
3928a8a2 | 4219 | |
3f5a54e3 SR |
4220 | atomic_notifier_chain_register(&panic_notifier_list, |
4221 | &trace_panic_notifier); | |
4222 | ||
4223 | register_die_notifier(&trace_die_notifier); | |
2fc1dfbe FW |
4224 | |
4225 | return 0; | |
3f5a54e3 | 4226 | |
9e01c1b7 | 4227 | out_free_cpumask: |
b04cc6b1 FW |
4228 | free_cpumask_var(tracing_reader_cpumask); |
4229 | out_free_tracing_cpumask: | |
9e01c1b7 RR |
4230 | free_cpumask_var(tracing_cpumask); |
4231 | out_free_buffer_mask: | |
4232 | free_cpumask_var(tracing_buffer_mask); | |
4233 | out: | |
4234 | return ret; | |
bc0c38d1 | 4235 | } |
b2821ae6 SR |
4236 | |
4237 | __init static int clear_boot_tracer(void) | |
4238 | { | |
4239 | /* | |
4240 | * The default tracer at boot buffer is an init section. | |
4241 | * This function is called in lateinit. If we did not | |
4242 | * find the boot tracer, then clear it out, to prevent | |
4243 | * later registration from accessing the buffer that is | |
4244 | * about to be freed. | |
4245 | */ | |
4246 | if (!default_bootup_tracer) | |
4247 | return 0; | |
4248 | ||
4249 | printk(KERN_INFO "ftrace bootup tracer '%s' not registered.\n", | |
4250 | default_bootup_tracer); | |
4251 | default_bootup_tracer = NULL; | |
4252 | ||
4253 | return 0; | |
4254 | } | |
4255 | ||
b5ad384e FW |
4256 | early_initcall(tracer_alloc_buffers); |
4257 | fs_initcall(tracer_init_debugfs); | |
b2821ae6 | 4258 | late_initcall(clear_boot_tracer); |