Commit | Line | Data |
---|---|---|
bc0c38d1 SR |
1 | /* |
2 | * ring buffer based function tracer | |
3 | * | |
2b6080f2 | 4 | * Copyright (C) 2007-2012 Steven Rostedt <srostedt@redhat.com> |
bc0c38d1 SR |
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 | |
6d49e352 | 12 | * Copyright (C) 2004 Nadia Yvette Chambers |
bc0c38d1 | 13 | */ |
2cadf913 | 14 | #include <linux/ring_buffer.h> |
273b281f | 15 | #include <generated/utsrelease.h> |
2cadf913 SR |
16 | #include <linux/stacktrace.h> |
17 | #include <linux/writeback.h> | |
bc0c38d1 SR |
18 | #include <linux/kallsyms.h> |
19 | #include <linux/seq_file.h> | |
3f5a54e3 | 20 | #include <linux/notifier.h> |
2cadf913 | 21 | #include <linux/irqflags.h> |
0d5c6e1c | 22 | #include <linux/irq_work.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> |
7e53bd42 | 35 | #include <linux/rwsem.h> |
5a0e3ad6 | 36 | #include <linux/slab.h> |
bc0c38d1 SR |
37 | #include <linux/ctype.h> |
38 | #include <linux/init.h> | |
2a2cc8f7 | 39 | #include <linux/poll.h> |
b892e5c8 | 40 | #include <linux/nmi.h> |
bc0c38d1 | 41 | #include <linux/fs.h> |
8bd75c77 | 42 | #include <linux/sched/rt.h> |
86387f7e | 43 | |
bc0c38d1 | 44 | #include "trace.h" |
f0868d1e | 45 | #include "trace_output.h" |
bc0c38d1 | 46 | |
73c5162a SR |
47 | /* |
48 | * On boot up, the ring buffer is set to the minimum size, so that | |
49 | * we do not waste memory on systems that are not using tracing. | |
50 | */ | |
020e5f85 | 51 | int ring_buffer_expanded; |
73c5162a | 52 | |
8e1b82e0 FW |
53 | /* |
54 | * We need to change this state when a selftest is running. | |
ff32504f FW |
55 | * A selftest will lurk into the ring-buffer to count the |
56 | * entries inserted during the selftest although some concurrent | |
5e1607a0 | 57 | * insertions into the ring-buffer such as trace_printk could occurred |
ff32504f FW |
58 | * at the same time, giving false positive or negative results. |
59 | */ | |
8e1b82e0 | 60 | static bool __read_mostly tracing_selftest_running; |
ff32504f | 61 | |
b2821ae6 SR |
62 | /* |
63 | * If a tracer is running, we do not want to run SELFTEST. | |
64 | */ | |
020e5f85 | 65 | bool __read_mostly tracing_selftest_disabled; |
b2821ae6 | 66 | |
adf9f195 FW |
67 | /* For tracers that don't implement custom flags */ |
68 | static struct tracer_opt dummy_tracer_opt[] = { | |
69 | { } | |
70 | }; | |
71 | ||
72 | static struct tracer_flags dummy_tracer_flags = { | |
73 | .val = 0, | |
74 | .opts = dummy_tracer_opt | |
75 | }; | |
76 | ||
77 | static int dummy_set_flag(u32 old_flags, u32 bit, int set) | |
78 | { | |
79 | return 0; | |
80 | } | |
0f048701 | 81 | |
7ffbd48d SR |
82 | /* |
83 | * To prevent the comm cache from being overwritten when no | |
84 | * tracing is active, only save the comm when a trace event | |
85 | * occurred. | |
86 | */ | |
87 | static DEFINE_PER_CPU(bool, trace_cmdline_save); | |
88 | ||
0d5c6e1c SR |
89 | /* |
90 | * When a reader is waiting for data, then this variable is | |
91 | * set to true. | |
92 | */ | |
93 | static bool trace_wakeup_needed; | |
94 | ||
95 | static struct irq_work trace_work_wakeup; | |
96 | ||
0f048701 SR |
97 | /* |
98 | * Kill all tracing for good (never come back). | |
99 | * It is initialized to 1 but will turn to zero if the initialization | |
100 | * of the tracer is successful. But that is the only place that sets | |
101 | * this back to zero. | |
102 | */ | |
4fd27358 | 103 | static int tracing_disabled = 1; |
0f048701 | 104 | |
9288f99a | 105 | DEFINE_PER_CPU(int, ftrace_cpu_disabled); |
d769041f | 106 | |
955b61e5 | 107 | cpumask_var_t __read_mostly tracing_buffer_mask; |
ab46428c | 108 | |
944ac425 SR |
109 | /* |
110 | * ftrace_dump_on_oops - variable to dump ftrace buffer on oops | |
111 | * | |
112 | * If there is an oops (or kernel panic) and the ftrace_dump_on_oops | |
113 | * is set, then ftrace_dump is called. This will output the contents | |
114 | * of the ftrace buffers to the console. This is very useful for | |
115 | * capturing traces that lead to crashes and outputing it to a | |
116 | * serial console. | |
117 | * | |
118 | * It is default off, but you can enable it with either specifying | |
119 | * "ftrace_dump_on_oops" in the kernel command line, or setting | |
cecbca96 FW |
120 | * /proc/sys/kernel/ftrace_dump_on_oops |
121 | * Set 1 if you want to dump buffers of all CPUs | |
122 | * Set 2 if you want to dump the buffer of the CPU that triggered oops | |
944ac425 | 123 | */ |
cecbca96 FW |
124 | |
125 | enum ftrace_dump_mode ftrace_dump_on_oops; | |
944ac425 | 126 | |
b2821ae6 SR |
127 | static int tracing_set_tracer(const char *buf); |
128 | ||
ee6c2c1b LZ |
129 | #define MAX_TRACER_SIZE 100 |
130 | static char bootup_tracer_buf[MAX_TRACER_SIZE] __initdata; | |
b2821ae6 | 131 | static char *default_bootup_tracer; |
d9e54076 | 132 | |
1beee96b | 133 | static int __init set_cmdline_ftrace(char *str) |
d9e54076 | 134 | { |
ee6c2c1b | 135 | strncpy(bootup_tracer_buf, str, MAX_TRACER_SIZE); |
b2821ae6 | 136 | default_bootup_tracer = bootup_tracer_buf; |
73c5162a SR |
137 | /* We are using ftrace early, expand it */ |
138 | ring_buffer_expanded = 1; | |
d9e54076 PZ |
139 | return 1; |
140 | } | |
1beee96b | 141 | __setup("ftrace=", set_cmdline_ftrace); |
d9e54076 | 142 | |
944ac425 SR |
143 | static int __init set_ftrace_dump_on_oops(char *str) |
144 | { | |
cecbca96 FW |
145 | if (*str++ != '=' || !*str) { |
146 | ftrace_dump_on_oops = DUMP_ALL; | |
147 | return 1; | |
148 | } | |
149 | ||
150 | if (!strcmp("orig_cpu", str)) { | |
151 | ftrace_dump_on_oops = DUMP_ORIG; | |
152 | return 1; | |
153 | } | |
154 | ||
155 | return 0; | |
944ac425 SR |
156 | } |
157 | __setup("ftrace_dump_on_oops", set_ftrace_dump_on_oops); | |
60a11774 | 158 | |
7bcfaf54 SR |
159 | |
160 | static char trace_boot_options_buf[MAX_TRACER_SIZE] __initdata; | |
161 | static char *trace_boot_options __initdata; | |
162 | ||
163 | static int __init set_trace_boot_options(char *str) | |
164 | { | |
165 | strncpy(trace_boot_options_buf, str, MAX_TRACER_SIZE); | |
166 | trace_boot_options = trace_boot_options_buf; | |
167 | return 0; | |
168 | } | |
169 | __setup("trace_options=", set_trace_boot_options); | |
170 | ||
cf8e3474 | 171 | unsigned long long ns2usecs(cycle_t nsec) |
bc0c38d1 SR |
172 | { |
173 | nsec += 500; | |
174 | do_div(nsec, 1000); | |
175 | return nsec; | |
176 | } | |
177 | ||
4fcdae83 SR |
178 | /* |
179 | * The global_trace is the descriptor that holds the tracing | |
180 | * buffers for the live tracing. For each CPU, it contains | |
181 | * a link list of pages that will store trace entries. The | |
182 | * page descriptor of the pages in the memory is used to hold | |
183 | * the link list by linking the lru item in the page descriptor | |
184 | * to each of the pages in the buffer per CPU. | |
185 | * | |
186 | * For each active CPU there is a data field that holds the | |
187 | * pages for the buffer for that CPU. Each CPU has the same number | |
188 | * of pages allocated for its buffer. | |
189 | */ | |
bc0c38d1 SR |
190 | static struct trace_array global_trace; |
191 | ||
ae63b31e SR |
192 | LIST_HEAD(ftrace_trace_arrays); |
193 | ||
e77405ad SR |
194 | int filter_current_check_discard(struct ring_buffer *buffer, |
195 | struct ftrace_event_call *call, void *rec, | |
eb02ce01 TZ |
196 | struct ring_buffer_event *event) |
197 | { | |
e77405ad | 198 | return filter_check_discard(call, rec, buffer, event); |
eb02ce01 | 199 | } |
17c873ec | 200 | EXPORT_SYMBOL_GPL(filter_current_check_discard); |
eb02ce01 | 201 | |
37886f6a SR |
202 | cycle_t ftrace_now(int cpu) |
203 | { | |
204 | u64 ts; | |
205 | ||
206 | /* Early boot up does not have a buffer yet */ | |
207 | if (!global_trace.buffer) | |
208 | return trace_clock_local(); | |
209 | ||
210 | ts = ring_buffer_time_stamp(global_trace.buffer, cpu); | |
211 | ring_buffer_normalize_time_stamp(global_trace.buffer, cpu, &ts); | |
212 | ||
213 | return ts; | |
214 | } | |
bc0c38d1 | 215 | |
4fcdae83 SR |
216 | /* |
217 | * The max_tr is used to snapshot the global_trace when a maximum | |
218 | * latency is reached. Some tracers will use this to store a maximum | |
219 | * trace while it continues examining live traces. | |
220 | * | |
221 | * The buffers for the max_tr are set up the same as the global_trace. | |
222 | * When a snapshot is taken, the link list of the max_tr is swapped | |
223 | * with the link list of the global_trace and the buffers are reset for | |
224 | * the global_trace so the tracing can continue. | |
225 | */ | |
bc0c38d1 SR |
226 | static struct trace_array max_tr; |
227 | ||
9036990d SR |
228 | int tracing_is_enabled(void) |
229 | { | |
0fb9656d | 230 | return tracing_is_on(); |
9036990d SR |
231 | } |
232 | ||
4fcdae83 | 233 | /* |
3928a8a2 SR |
234 | * trace_buf_size is the size in bytes that is allocated |
235 | * for a buffer. Note, the number of bytes is always rounded | |
236 | * to page size. | |
3f5a54e3 SR |
237 | * |
238 | * This number is purposely set to a low number of 16384. | |
239 | * If the dump on oops happens, it will be much appreciated | |
240 | * to not have to wait for all that output. Anyway this can be | |
241 | * boot time and run time configurable. | |
4fcdae83 | 242 | */ |
3928a8a2 | 243 | #define TRACE_BUF_SIZE_DEFAULT 1441792UL /* 16384 * 88 (sizeof(entry)) */ |
3f5a54e3 | 244 | |
3928a8a2 | 245 | static unsigned long trace_buf_size = TRACE_BUF_SIZE_DEFAULT; |
bc0c38d1 | 246 | |
4fcdae83 | 247 | /* trace_types holds a link list of available tracers. */ |
bc0c38d1 | 248 | static struct tracer *trace_types __read_mostly; |
4fcdae83 | 249 | |
4fcdae83 SR |
250 | /* |
251 | * trace_types_lock is used to protect the trace_types list. | |
4fcdae83 | 252 | */ |
bc0c38d1 | 253 | static DEFINE_MUTEX(trace_types_lock); |
4fcdae83 | 254 | |
7e53bd42 LJ |
255 | /* |
256 | * serialize the access of the ring buffer | |
257 | * | |
258 | * ring buffer serializes readers, but it is low level protection. | |
259 | * The validity of the events (which returns by ring_buffer_peek() ..etc) | |
260 | * are not protected by ring buffer. | |
261 | * | |
262 | * The content of events may become garbage if we allow other process consumes | |
263 | * these events concurrently: | |
264 | * A) the page of the consumed events may become a normal page | |
265 | * (not reader page) in ring buffer, and this page will be rewrited | |
266 | * by events producer. | |
267 | * B) The page of the consumed events may become a page for splice_read, | |
268 | * and this page will be returned to system. | |
269 | * | |
270 | * These primitives allow multi process access to different cpu ring buffer | |
271 | * concurrently. | |
272 | * | |
273 | * These primitives don't distinguish read-only and read-consume access. | |
274 | * Multi read-only access are also serialized. | |
275 | */ | |
276 | ||
277 | #ifdef CONFIG_SMP | |
278 | static DECLARE_RWSEM(all_cpu_access_lock); | |
279 | static DEFINE_PER_CPU(struct mutex, cpu_access_lock); | |
280 | ||
281 | static inline void trace_access_lock(int cpu) | |
282 | { | |
ae3b5093 | 283 | if (cpu == RING_BUFFER_ALL_CPUS) { |
7e53bd42 LJ |
284 | /* gain it for accessing the whole ring buffer. */ |
285 | down_write(&all_cpu_access_lock); | |
286 | } else { | |
287 | /* gain it for accessing a cpu ring buffer. */ | |
288 | ||
ae3b5093 | 289 | /* Firstly block other trace_access_lock(RING_BUFFER_ALL_CPUS). */ |
7e53bd42 LJ |
290 | down_read(&all_cpu_access_lock); |
291 | ||
292 | /* Secondly block other access to this @cpu ring buffer. */ | |
293 | mutex_lock(&per_cpu(cpu_access_lock, cpu)); | |
294 | } | |
295 | } | |
296 | ||
297 | static inline void trace_access_unlock(int cpu) | |
298 | { | |
ae3b5093 | 299 | if (cpu == RING_BUFFER_ALL_CPUS) { |
7e53bd42 LJ |
300 | up_write(&all_cpu_access_lock); |
301 | } else { | |
302 | mutex_unlock(&per_cpu(cpu_access_lock, cpu)); | |
303 | up_read(&all_cpu_access_lock); | |
304 | } | |
305 | } | |
306 | ||
307 | static inline void trace_access_lock_init(void) | |
308 | { | |
309 | int cpu; | |
310 | ||
311 | for_each_possible_cpu(cpu) | |
312 | mutex_init(&per_cpu(cpu_access_lock, cpu)); | |
313 | } | |
314 | ||
315 | #else | |
316 | ||
317 | static DEFINE_MUTEX(access_lock); | |
318 | ||
319 | static inline void trace_access_lock(int cpu) | |
320 | { | |
321 | (void)cpu; | |
322 | mutex_lock(&access_lock); | |
323 | } | |
324 | ||
325 | static inline void trace_access_unlock(int cpu) | |
326 | { | |
327 | (void)cpu; | |
328 | mutex_unlock(&access_lock); | |
329 | } | |
330 | ||
331 | static inline void trace_access_lock_init(void) | |
332 | { | |
333 | } | |
334 | ||
335 | #endif | |
336 | ||
4fcdae83 | 337 | /* trace_wait is a waitqueue for tasks blocked on trace_poll */ |
4e655519 IM |
338 | static DECLARE_WAIT_QUEUE_HEAD(trace_wait); |
339 | ||
ee6bce52 | 340 | /* trace_flags holds trace_options default values */ |
12ef7d44 | 341 | unsigned long trace_flags = TRACE_ITER_PRINT_PARENT | TRACE_ITER_PRINTK | |
a2a16d6a | 342 | TRACE_ITER_ANNOTATE | TRACE_ITER_CONTEXT_INFO | TRACE_ITER_SLEEP_TIME | |
77271ce4 | 343 | TRACE_ITER_GRAPH_TIME | TRACE_ITER_RECORD_CMD | TRACE_ITER_OVERWRITE | |
5224c3a3 | 344 | TRACE_ITER_IRQ_INFO | TRACE_ITER_MARKERS; |
4e655519 | 345 | |
0d5c6e1c SR |
346 | /** |
347 | * trace_wake_up - wake up tasks waiting for trace input | |
348 | * | |
349 | * Schedules a delayed work to wake up any task that is blocked on the | |
350 | * trace_wait queue. These is used with trace_poll for tasks polling the | |
351 | * trace. | |
352 | */ | |
353 | static void trace_wake_up(struct irq_work *work) | |
e7e2ee89 | 354 | { |
0d5c6e1c | 355 | wake_up_all(&trace_wait); |
e7e2ee89 | 356 | |
0d5c6e1c | 357 | } |
e7e2ee89 | 358 | |
499e5470 SR |
359 | /** |
360 | * tracing_on - enable tracing buffers | |
361 | * | |
362 | * This function enables tracing buffers that may have been | |
363 | * disabled with tracing_off. | |
364 | */ | |
365 | void tracing_on(void) | |
366 | { | |
367 | if (global_trace.buffer) | |
368 | ring_buffer_record_on(global_trace.buffer); | |
369 | /* | |
370 | * This flag is only looked at when buffers haven't been | |
371 | * allocated yet. We don't really care about the race | |
372 | * between setting this flag and actually turning | |
373 | * on the buffer. | |
374 | */ | |
375 | global_trace.buffer_disabled = 0; | |
376 | } | |
377 | EXPORT_SYMBOL_GPL(tracing_on); | |
378 | ||
379 | /** | |
380 | * tracing_off - turn off tracing buffers | |
381 | * | |
382 | * This function stops the tracing buffers from recording data. | |
383 | * It does not disable any overhead the tracers themselves may | |
384 | * be causing. This function simply causes all recording to | |
385 | * the ring buffers to fail. | |
386 | */ | |
387 | void tracing_off(void) | |
388 | { | |
389 | if (global_trace.buffer) | |
f2bf1f6f | 390 | ring_buffer_record_off(global_trace.buffer); |
499e5470 SR |
391 | /* |
392 | * This flag is only looked at when buffers haven't been | |
393 | * allocated yet. We don't really care about the race | |
394 | * between setting this flag and actually turning | |
395 | * on the buffer. | |
396 | */ | |
397 | global_trace.buffer_disabled = 1; | |
398 | } | |
399 | EXPORT_SYMBOL_GPL(tracing_off); | |
400 | ||
401 | /** | |
402 | * tracing_is_on - show state of ring buffers enabled | |
403 | */ | |
404 | int tracing_is_on(void) | |
405 | { | |
406 | if (global_trace.buffer) | |
407 | return ring_buffer_record_is_on(global_trace.buffer); | |
408 | return !global_trace.buffer_disabled; | |
409 | } | |
410 | EXPORT_SYMBOL_GPL(tracing_is_on); | |
411 | ||
3928a8a2 | 412 | static int __init set_buf_size(char *str) |
bc0c38d1 | 413 | { |
3928a8a2 | 414 | unsigned long buf_size; |
c6caeeb1 | 415 | |
bc0c38d1 SR |
416 | if (!str) |
417 | return 0; | |
9d612bef | 418 | buf_size = memparse(str, &str); |
c6caeeb1 | 419 | /* nr_entries can not be zero */ |
9d612bef | 420 | if (buf_size == 0) |
c6caeeb1 | 421 | return 0; |
3928a8a2 | 422 | trace_buf_size = buf_size; |
bc0c38d1 SR |
423 | return 1; |
424 | } | |
3928a8a2 | 425 | __setup("trace_buf_size=", set_buf_size); |
bc0c38d1 | 426 | |
0e950173 TB |
427 | static int __init set_tracing_thresh(char *str) |
428 | { | |
87abb3b1 | 429 | unsigned long threshold; |
0e950173 TB |
430 | int ret; |
431 | ||
432 | if (!str) | |
433 | return 0; | |
bcd83ea6 | 434 | ret = kstrtoul(str, 0, &threshold); |
0e950173 TB |
435 | if (ret < 0) |
436 | return 0; | |
87abb3b1 | 437 | tracing_thresh = threshold * 1000; |
0e950173 TB |
438 | return 1; |
439 | } | |
440 | __setup("tracing_thresh=", set_tracing_thresh); | |
441 | ||
57f50be1 SR |
442 | unsigned long nsecs_to_usecs(unsigned long nsecs) |
443 | { | |
444 | return nsecs / 1000; | |
445 | } | |
446 | ||
4fcdae83 | 447 | /* These must match the bit postions in trace_iterator_flags */ |
bc0c38d1 SR |
448 | static const char *trace_options[] = { |
449 | "print-parent", | |
450 | "sym-offset", | |
451 | "sym-addr", | |
452 | "verbose", | |
f9896bf3 | 453 | "raw", |
5e3ca0ec | 454 | "hex", |
cb0f12aa | 455 | "bin", |
2a2cc8f7 | 456 | "block", |
86387f7e | 457 | "stacktrace", |
5e1607a0 | 458 | "trace_printk", |
b2a866f9 | 459 | "ftrace_preempt", |
9f029e83 | 460 | "branch", |
12ef7d44 | 461 | "annotate", |
02b67518 | 462 | "userstacktrace", |
b54d3de9 | 463 | "sym-userobj", |
66896a85 | 464 | "printk-msg-only", |
c4a8e8be | 465 | "context-info", |
c032ef64 | 466 | "latency-format", |
be6f164a | 467 | "sleep-time", |
a2a16d6a | 468 | "graph-time", |
e870e9a1 | 469 | "record-cmd", |
750912fa | 470 | "overwrite", |
cf30cf67 | 471 | "disable_on_free", |
77271ce4 | 472 | "irq-info", |
5224c3a3 | 473 | "markers", |
bc0c38d1 SR |
474 | NULL |
475 | }; | |
476 | ||
5079f326 Z |
477 | static struct { |
478 | u64 (*func)(void); | |
479 | const char *name; | |
8be0709f | 480 | int in_ns; /* is this clock in nanoseconds? */ |
5079f326 | 481 | } trace_clocks[] = { |
8be0709f DS |
482 | { trace_clock_local, "local", 1 }, |
483 | { trace_clock_global, "global", 1 }, | |
484 | { trace_clock_counter, "counter", 0 }, | |
8cbd9cc6 | 485 | ARCH_TRACE_CLOCKS |
5079f326 Z |
486 | }; |
487 | ||
488 | int trace_clock_id; | |
489 | ||
b63f39ea | 490 | /* |
491 | * trace_parser_get_init - gets the buffer for trace parser | |
492 | */ | |
493 | int trace_parser_get_init(struct trace_parser *parser, int size) | |
494 | { | |
495 | memset(parser, 0, sizeof(*parser)); | |
496 | ||
497 | parser->buffer = kmalloc(size, GFP_KERNEL); | |
498 | if (!parser->buffer) | |
499 | return 1; | |
500 | ||
501 | parser->size = size; | |
502 | return 0; | |
503 | } | |
504 | ||
505 | /* | |
506 | * trace_parser_put - frees the buffer for trace parser | |
507 | */ | |
508 | void trace_parser_put(struct trace_parser *parser) | |
509 | { | |
510 | kfree(parser->buffer); | |
511 | } | |
512 | ||
513 | /* | |
514 | * trace_get_user - reads the user input string separated by space | |
515 | * (matched by isspace(ch)) | |
516 | * | |
517 | * For each string found the 'struct trace_parser' is updated, | |
518 | * and the function returns. | |
519 | * | |
520 | * Returns number of bytes read. | |
521 | * | |
522 | * See kernel/trace/trace.h for 'struct trace_parser' details. | |
523 | */ | |
524 | int trace_get_user(struct trace_parser *parser, const char __user *ubuf, | |
525 | size_t cnt, loff_t *ppos) | |
526 | { | |
527 | char ch; | |
528 | size_t read = 0; | |
529 | ssize_t ret; | |
530 | ||
531 | if (!*ppos) | |
532 | trace_parser_clear(parser); | |
533 | ||
534 | ret = get_user(ch, ubuf++); | |
535 | if (ret) | |
536 | goto out; | |
537 | ||
538 | read++; | |
539 | cnt--; | |
540 | ||
541 | /* | |
542 | * The parser is not finished with the last write, | |
543 | * continue reading the user input without skipping spaces. | |
544 | */ | |
545 | if (!parser->cont) { | |
546 | /* skip white space */ | |
547 | while (cnt && isspace(ch)) { | |
548 | ret = get_user(ch, ubuf++); | |
549 | if (ret) | |
550 | goto out; | |
551 | read++; | |
552 | cnt--; | |
553 | } | |
554 | ||
555 | /* only spaces were written */ | |
556 | if (isspace(ch)) { | |
557 | *ppos += read; | |
558 | ret = read; | |
559 | goto out; | |
560 | } | |
561 | ||
562 | parser->idx = 0; | |
563 | } | |
564 | ||
565 | /* read the non-space input */ | |
566 | while (cnt && !isspace(ch)) { | |
3c235a33 | 567 | if (parser->idx < parser->size - 1) |
b63f39ea | 568 | parser->buffer[parser->idx++] = ch; |
569 | else { | |
570 | ret = -EINVAL; | |
571 | goto out; | |
572 | } | |
573 | ret = get_user(ch, ubuf++); | |
574 | if (ret) | |
575 | goto out; | |
576 | read++; | |
577 | cnt--; | |
578 | } | |
579 | ||
580 | /* We either got finished input or we have to wait for another call. */ | |
581 | if (isspace(ch)) { | |
582 | parser->buffer[parser->idx] = 0; | |
583 | parser->cont = false; | |
584 | } else { | |
585 | parser->cont = true; | |
586 | parser->buffer[parser->idx++] = ch; | |
587 | } | |
588 | ||
589 | *ppos += read; | |
590 | ret = read; | |
591 | ||
592 | out: | |
593 | return ret; | |
594 | } | |
595 | ||
6c6c2796 PP |
596 | ssize_t trace_seq_to_user(struct trace_seq *s, char __user *ubuf, size_t cnt) |
597 | { | |
598 | int len; | |
599 | int ret; | |
600 | ||
2dc5d12b SR |
601 | if (!cnt) |
602 | return 0; | |
603 | ||
6c6c2796 PP |
604 | if (s->len <= s->readpos) |
605 | return -EBUSY; | |
606 | ||
607 | len = s->len - s->readpos; | |
608 | if (cnt > len) | |
609 | cnt = len; | |
610 | ret = copy_to_user(ubuf, s->buffer + s->readpos, cnt); | |
2dc5d12b | 611 | if (ret == cnt) |
6c6c2796 PP |
612 | return -EFAULT; |
613 | ||
2dc5d12b SR |
614 | cnt -= ret; |
615 | ||
e74da523 | 616 | s->readpos += cnt; |
6c6c2796 | 617 | return cnt; |
214023c3 SR |
618 | } |
619 | ||
b8b94265 | 620 | static ssize_t trace_seq_to_buffer(struct trace_seq *s, void *buf, size_t cnt) |
3c56819b EGM |
621 | { |
622 | int len; | |
3c56819b EGM |
623 | |
624 | if (s->len <= s->readpos) | |
625 | return -EBUSY; | |
626 | ||
627 | len = s->len - s->readpos; | |
628 | if (cnt > len) | |
629 | cnt = len; | |
5a26c8f0 | 630 | memcpy(buf, s->buffer + s->readpos, cnt); |
3c56819b | 631 | |
e74da523 | 632 | s->readpos += cnt; |
3c56819b EGM |
633 | return cnt; |
634 | } | |
635 | ||
5d4a9dba SR |
636 | /* |
637 | * ftrace_max_lock is used to protect the swapping of buffers | |
638 | * when taking a max snapshot. The buffers themselves are | |
639 | * protected by per_cpu spinlocks. But the action of the swap | |
640 | * needs its own lock. | |
641 | * | |
445c8951 | 642 | * This is defined as a arch_spinlock_t in order to help |
5d4a9dba SR |
643 | * with performance when lockdep debugging is enabled. |
644 | * | |
645 | * It is also used in other places outside the update_max_tr | |
646 | * so it needs to be defined outside of the | |
647 | * CONFIG_TRACER_MAX_TRACE. | |
648 | */ | |
445c8951 | 649 | static arch_spinlock_t ftrace_max_lock = |
edc35bd7 | 650 | (arch_spinlock_t)__ARCH_SPIN_LOCK_UNLOCKED; |
5d4a9dba | 651 | |
0e950173 TB |
652 | unsigned long __read_mostly tracing_thresh; |
653 | ||
5d4a9dba SR |
654 | #ifdef CONFIG_TRACER_MAX_TRACE |
655 | unsigned long __read_mostly tracing_max_latency; | |
5d4a9dba SR |
656 | |
657 | /* | |
658 | * Copy the new maximum trace into the separate maximum-trace | |
659 | * structure. (this way the maximum trace is permanently saved, | |
660 | * for later retrieval via /sys/kernel/debug/tracing/latency_trace) | |
661 | */ | |
662 | static void | |
663 | __update_max_tr(struct trace_array *tr, struct task_struct *tsk, int cpu) | |
664 | { | |
a7603ff4 | 665 | struct trace_array_cpu *data = per_cpu_ptr(tr->data, cpu); |
1acaa1b2 | 666 | struct trace_array_cpu *max_data; |
5d4a9dba SR |
667 | |
668 | max_tr.cpu = cpu; | |
669 | max_tr.time_start = data->preempt_timestamp; | |
670 | ||
a7603ff4 | 671 | max_data = per_cpu_ptr(max_tr.data, cpu); |
8248ac05 SR |
672 | max_data->saved_latency = tracing_max_latency; |
673 | max_data->critical_start = data->critical_start; | |
674 | max_data->critical_end = data->critical_end; | |
5d4a9dba | 675 | |
1acaa1b2 | 676 | memcpy(max_data->comm, tsk->comm, TASK_COMM_LEN); |
8248ac05 SR |
677 | max_data->pid = tsk->pid; |
678 | max_data->uid = task_uid(tsk); | |
679 | max_data->nice = tsk->static_prio - 20 - MAX_RT_PRIO; | |
680 | max_data->policy = tsk->policy; | |
681 | max_data->rt_priority = tsk->rt_priority; | |
5d4a9dba SR |
682 | |
683 | /* record this tasks comm */ | |
684 | tracing_record_cmdline(tsk); | |
685 | } | |
686 | ||
4fcdae83 SR |
687 | /** |
688 | * update_max_tr - snapshot all trace buffers from global_trace to max_tr | |
689 | * @tr: tracer | |
690 | * @tsk: the task with the latency | |
691 | * @cpu: The cpu that initiated the trace. | |
692 | * | |
693 | * Flip the buffers between the @tr and the max_tr and record information | |
694 | * about which task was the cause of this latency. | |
695 | */ | |
e309b41d | 696 | void |
bc0c38d1 SR |
697 | update_max_tr(struct trace_array *tr, struct task_struct *tsk, int cpu) |
698 | { | |
2721e72d | 699 | struct ring_buffer *buf; |
bc0c38d1 | 700 | |
2b6080f2 | 701 | if (tr->stop_count) |
b8de7bd1 SR |
702 | return; |
703 | ||
4c11d7ae | 704 | WARN_ON_ONCE(!irqs_disabled()); |
34600f0e | 705 | |
2b6080f2 | 706 | if (!tr->current_trace->allocated_snapshot) { |
debdd57f | 707 | /* Only the nop tracer should hit this when disabling */ |
2b6080f2 | 708 | WARN_ON_ONCE(tr->current_trace != &nop_trace); |
34600f0e | 709 | return; |
debdd57f | 710 | } |
34600f0e | 711 | |
0199c4e6 | 712 | arch_spin_lock(&ftrace_max_lock); |
3928a8a2 | 713 | |
2721e72d | 714 | buf = tr->buffer; |
3928a8a2 SR |
715 | tr->buffer = max_tr.buffer; |
716 | max_tr.buffer = buf; | |
717 | ||
bc0c38d1 | 718 | __update_max_tr(tr, tsk, cpu); |
0199c4e6 | 719 | arch_spin_unlock(&ftrace_max_lock); |
bc0c38d1 SR |
720 | } |
721 | ||
722 | /** | |
723 | * update_max_tr_single - only copy one trace over, and reset the rest | |
724 | * @tr - tracer | |
725 | * @tsk - task with the latency | |
726 | * @cpu - the cpu of the buffer to copy. | |
4fcdae83 SR |
727 | * |
728 | * Flip the trace of a single CPU buffer between the @tr and the max_tr. | |
bc0c38d1 | 729 | */ |
e309b41d | 730 | void |
bc0c38d1 SR |
731 | update_max_tr_single(struct trace_array *tr, struct task_struct *tsk, int cpu) |
732 | { | |
3928a8a2 | 733 | int ret; |
bc0c38d1 | 734 | |
2b6080f2 | 735 | if (tr->stop_count) |
b8de7bd1 SR |
736 | return; |
737 | ||
4c11d7ae | 738 | WARN_ON_ONCE(!irqs_disabled()); |
2b6080f2 | 739 | if (WARN_ON_ONCE(!tr->current_trace->allocated_snapshot)) |
ef710e10 | 740 | return; |
ef710e10 | 741 | |
0199c4e6 | 742 | arch_spin_lock(&ftrace_max_lock); |
bc0c38d1 | 743 | |
3928a8a2 SR |
744 | ret = ring_buffer_swap_cpu(max_tr.buffer, tr->buffer, cpu); |
745 | ||
e8165dbb SR |
746 | if (ret == -EBUSY) { |
747 | /* | |
748 | * We failed to swap the buffer due to a commit taking | |
749 | * place on this CPU. We fail to record, but we reset | |
750 | * the max trace buffer (no one writes directly to it) | |
751 | * and flag that it failed. | |
752 | */ | |
753 | trace_array_printk(&max_tr, _THIS_IP_, | |
754 | "Failed to swap buffers due to commit in progress\n"); | |
755 | } | |
756 | ||
e8165dbb | 757 | WARN_ON_ONCE(ret && ret != -EAGAIN && ret != -EBUSY); |
bc0c38d1 SR |
758 | |
759 | __update_max_tr(tr, tsk, cpu); | |
0199c4e6 | 760 | arch_spin_unlock(&ftrace_max_lock); |
bc0c38d1 | 761 | } |
5d4a9dba | 762 | #endif /* CONFIG_TRACER_MAX_TRACE */ |
bc0c38d1 | 763 | |
0d5c6e1c SR |
764 | static void default_wait_pipe(struct trace_iterator *iter) |
765 | { | |
766 | DEFINE_WAIT(wait); | |
767 | ||
768 | prepare_to_wait(&trace_wait, &wait, TASK_INTERRUPTIBLE); | |
769 | ||
770 | /* | |
771 | * The events can happen in critical sections where | |
772 | * checking a work queue can cause deadlocks. | |
773 | * After adding a task to the queue, this flag is set | |
774 | * only to notify events to try to wake up the queue | |
775 | * using irq_work. | |
776 | * | |
777 | * We don't clear it even if the buffer is no longer | |
778 | * empty. The flag only causes the next event to run | |
779 | * irq_work to do the work queue wake up. The worse | |
780 | * that can happen if we race with !trace_empty() is that | |
781 | * an event will cause an irq_work to try to wake up | |
782 | * an empty queue. | |
783 | * | |
784 | * There's no reason to protect this flag either, as | |
785 | * the work queue and irq_work logic will do the necessary | |
786 | * synchronization for the wake ups. The only thing | |
787 | * that is necessary is that the wake up happens after | |
788 | * a task has been queued. It's OK for spurious wake ups. | |
789 | */ | |
790 | trace_wakeup_needed = true; | |
791 | ||
792 | if (trace_empty(iter)) | |
793 | schedule(); | |
794 | ||
795 | finish_wait(&trace_wait, &wait); | |
796 | } | |
797 | ||
4fcdae83 SR |
798 | /** |
799 | * register_tracer - register a tracer with the ftrace system. | |
800 | * @type - the plugin for the tracer | |
801 | * | |
802 | * Register a new plugin tracer. | |
803 | */ | |
bc0c38d1 SR |
804 | int register_tracer(struct tracer *type) |
805 | { | |
806 | struct tracer *t; | |
bc0c38d1 SR |
807 | int ret = 0; |
808 | ||
809 | if (!type->name) { | |
810 | pr_info("Tracer must have a name\n"); | |
811 | return -1; | |
812 | } | |
813 | ||
24a461d5 | 814 | if (strlen(type->name) >= MAX_TRACER_SIZE) { |
ee6c2c1b LZ |
815 | pr_info("Tracer has a name longer than %d\n", MAX_TRACER_SIZE); |
816 | return -1; | |
817 | } | |
818 | ||
bc0c38d1 | 819 | mutex_lock(&trace_types_lock); |
86fa2f60 | 820 | |
8e1b82e0 FW |
821 | tracing_selftest_running = true; |
822 | ||
bc0c38d1 SR |
823 | for (t = trace_types; t; t = t->next) { |
824 | if (strcmp(type->name, t->name) == 0) { | |
825 | /* already found */ | |
ee6c2c1b | 826 | pr_info("Tracer %s already registered\n", |
bc0c38d1 SR |
827 | type->name); |
828 | ret = -1; | |
829 | goto out; | |
830 | } | |
831 | } | |
832 | ||
adf9f195 FW |
833 | if (!type->set_flag) |
834 | type->set_flag = &dummy_set_flag; | |
835 | if (!type->flags) | |
836 | type->flags = &dummy_tracer_flags; | |
837 | else | |
838 | if (!type->flags->opts) | |
839 | type->flags->opts = dummy_tracer_opt; | |
6eaaa5d5 FW |
840 | if (!type->wait_pipe) |
841 | type->wait_pipe = default_wait_pipe; | |
842 | ||
adf9f195 | 843 | |
60a11774 | 844 | #ifdef CONFIG_FTRACE_STARTUP_TEST |
b2821ae6 | 845 | if (type->selftest && !tracing_selftest_disabled) { |
60a11774 | 846 | struct trace_array *tr = &global_trace; |
2b6080f2 | 847 | struct tracer *saved_tracer = tr->current_trace; |
ff32504f | 848 | |
60a11774 SR |
849 | /* |
850 | * Run a selftest on this tracer. | |
851 | * Here we reset the trace buffer, and set the current | |
852 | * tracer to be this tracer. The tracer can then run some | |
853 | * internal tracing to verify that everything is in order. | |
854 | * If we fail, we do not register this tracer. | |
855 | */ | |
76f0d073 | 856 | tracing_reset_online_cpus(tr); |
86fa2f60 | 857 | |
2b6080f2 | 858 | tr->current_trace = type; |
4a0b1665 | 859 | |
debdd57f HT |
860 | if (type->use_max_tr) { |
861 | /* If we expanded the buffers, make sure the max is expanded too */ | |
862 | if (ring_buffer_expanded) | |
863 | ring_buffer_resize(max_tr.buffer, trace_buf_size, | |
864 | RING_BUFFER_ALL_CPUS); | |
865 | type->allocated_snapshot = true; | |
866 | } | |
4a0b1665 | 867 | |
60a11774 SR |
868 | /* the test is responsible for initializing and enabling */ |
869 | pr_info("Testing tracer %s: ", type->name); | |
870 | ret = type->selftest(type, tr); | |
871 | /* the test is responsible for resetting too */ | |
2b6080f2 | 872 | tr->current_trace = saved_tracer; |
60a11774 SR |
873 | if (ret) { |
874 | printk(KERN_CONT "FAILED!\n"); | |
0be61ebc SR |
875 | /* Add the warning after printing 'FAILED' */ |
876 | WARN_ON(1); | |
60a11774 SR |
877 | goto out; |
878 | } | |
1d4db00a | 879 | /* Only reset on passing, to avoid touching corrupted buffers */ |
76f0d073 | 880 | tracing_reset_online_cpus(tr); |
86fa2f60 | 881 | |
debdd57f HT |
882 | if (type->use_max_tr) { |
883 | type->allocated_snapshot = false; | |
884 | ||
885 | /* Shrink the max buffer again */ | |
886 | if (ring_buffer_expanded) | |
887 | ring_buffer_resize(max_tr.buffer, 1, | |
888 | RING_BUFFER_ALL_CPUS); | |
889 | } | |
4a0b1665 | 890 | |
60a11774 SR |
891 | printk(KERN_CONT "PASSED\n"); |
892 | } | |
893 | #endif | |
894 | ||
bc0c38d1 SR |
895 | type->next = trace_types; |
896 | trace_types = type; | |
60a11774 | 897 | |
bc0c38d1 | 898 | out: |
8e1b82e0 | 899 | tracing_selftest_running = false; |
bc0c38d1 SR |
900 | mutex_unlock(&trace_types_lock); |
901 | ||
dac74940 SR |
902 | if (ret || !default_bootup_tracer) |
903 | goto out_unlock; | |
904 | ||
ee6c2c1b | 905 | if (strncmp(default_bootup_tracer, type->name, MAX_TRACER_SIZE)) |
dac74940 SR |
906 | goto out_unlock; |
907 | ||
908 | printk(KERN_INFO "Starting tracer '%s'\n", type->name); | |
909 | /* Do we want this tracer to start on bootup? */ | |
910 | tracing_set_tracer(type->name); | |
911 | default_bootup_tracer = NULL; | |
912 | /* disable other selftests, since this will break it. */ | |
913 | tracing_selftest_disabled = 1; | |
b2821ae6 | 914 | #ifdef CONFIG_FTRACE_STARTUP_TEST |
dac74940 SR |
915 | printk(KERN_INFO "Disabling FTRACE selftests due to running tracer '%s'\n", |
916 | type->name); | |
b2821ae6 | 917 | #endif |
b2821ae6 | 918 | |
dac74940 | 919 | out_unlock: |
bc0c38d1 SR |
920 | return ret; |
921 | } | |
922 | ||
f633903a SR |
923 | void tracing_reset(struct trace_array *tr, int cpu) |
924 | { | |
925 | struct ring_buffer *buffer = tr->buffer; | |
926 | ||
a5416411 HT |
927 | if (!buffer) |
928 | return; | |
929 | ||
f633903a SR |
930 | ring_buffer_record_disable(buffer); |
931 | ||
932 | /* Make sure all commits have finished */ | |
933 | synchronize_sched(); | |
68179686 | 934 | ring_buffer_reset_cpu(buffer, cpu); |
f633903a SR |
935 | |
936 | ring_buffer_record_enable(buffer); | |
937 | } | |
938 | ||
213cc060 PE |
939 | void tracing_reset_online_cpus(struct trace_array *tr) |
940 | { | |
621968cd | 941 | struct ring_buffer *buffer = tr->buffer; |
213cc060 PE |
942 | int cpu; |
943 | ||
a5416411 HT |
944 | if (!buffer) |
945 | return; | |
946 | ||
621968cd SR |
947 | ring_buffer_record_disable(buffer); |
948 | ||
949 | /* Make sure all commits have finished */ | |
950 | synchronize_sched(); | |
951 | ||
213cc060 PE |
952 | tr->time_start = ftrace_now(tr->cpu); |
953 | ||
954 | for_each_online_cpu(cpu) | |
68179686 | 955 | ring_buffer_reset_cpu(buffer, cpu); |
621968cd SR |
956 | |
957 | ring_buffer_record_enable(buffer); | |
213cc060 PE |
958 | } |
959 | ||
9456f0fa SR |
960 | void tracing_reset_current(int cpu) |
961 | { | |
962 | tracing_reset(&global_trace, cpu); | |
963 | } | |
964 | ||
965 | void tracing_reset_current_online_cpus(void) | |
966 | { | |
967 | tracing_reset_online_cpus(&global_trace); | |
968 | } | |
969 | ||
bc0c38d1 | 970 | #define SAVED_CMDLINES 128 |
2c7eea4c | 971 | #define NO_CMDLINE_MAP UINT_MAX |
bc0c38d1 SR |
972 | static unsigned map_pid_to_cmdline[PID_MAX_DEFAULT+1]; |
973 | static unsigned map_cmdline_to_pid[SAVED_CMDLINES]; | |
974 | static char saved_cmdlines[SAVED_CMDLINES][TASK_COMM_LEN]; | |
975 | static int cmdline_idx; | |
edc35bd7 | 976 | static arch_spinlock_t trace_cmdline_lock = __ARCH_SPIN_LOCK_UNLOCKED; |
25b0b44a | 977 | |
25b0b44a | 978 | /* temporary disable recording */ |
4fd27358 | 979 | static atomic_t trace_record_cmdline_disabled __read_mostly; |
bc0c38d1 SR |
980 | |
981 | static void trace_init_cmdlines(void) | |
982 | { | |
2c7eea4c TG |
983 | memset(&map_pid_to_cmdline, NO_CMDLINE_MAP, sizeof(map_pid_to_cmdline)); |
984 | memset(&map_cmdline_to_pid, NO_CMDLINE_MAP, sizeof(map_cmdline_to_pid)); | |
bc0c38d1 SR |
985 | cmdline_idx = 0; |
986 | } | |
987 | ||
b5130b1e CE |
988 | int is_tracing_stopped(void) |
989 | { | |
2b6080f2 | 990 | return global_trace.stop_count; |
b5130b1e CE |
991 | } |
992 | ||
69bb54ec SR |
993 | /** |
994 | * ftrace_off_permanent - disable all ftrace code permanently | |
995 | * | |
996 | * This should only be called when a serious anomally has | |
997 | * been detected. This will turn off the function tracing, | |
998 | * ring buffers, and other tracing utilites. It takes no | |
999 | * locks and can be called from any context. | |
1000 | */ | |
1001 | void ftrace_off_permanent(void) | |
1002 | { | |
1003 | tracing_disabled = 1; | |
1004 | ftrace_stop(); | |
1005 | tracing_off_permanent(); | |
1006 | } | |
1007 | ||
0f048701 SR |
1008 | /** |
1009 | * tracing_start - quick start of the tracer | |
1010 | * | |
1011 | * If tracing is enabled but was stopped by tracing_stop, | |
1012 | * this will start the tracer back up. | |
1013 | */ | |
1014 | void tracing_start(void) | |
1015 | { | |
1016 | struct ring_buffer *buffer; | |
1017 | unsigned long flags; | |
1018 | ||
1019 | if (tracing_disabled) | |
1020 | return; | |
1021 | ||
2b6080f2 SR |
1022 | raw_spin_lock_irqsave(&global_trace.start_lock, flags); |
1023 | if (--global_trace.stop_count) { | |
1024 | if (global_trace.stop_count < 0) { | |
b06a8301 SR |
1025 | /* Someone screwed up their debugging */ |
1026 | WARN_ON_ONCE(1); | |
2b6080f2 | 1027 | global_trace.stop_count = 0; |
b06a8301 | 1028 | } |
0f048701 SR |
1029 | goto out; |
1030 | } | |
1031 | ||
a2f80714 SR |
1032 | /* Prevent the buffers from switching */ |
1033 | arch_spin_lock(&ftrace_max_lock); | |
0f048701 SR |
1034 | |
1035 | buffer = global_trace.buffer; | |
1036 | if (buffer) | |
1037 | ring_buffer_record_enable(buffer); | |
1038 | ||
1039 | buffer = max_tr.buffer; | |
1040 | if (buffer) | |
1041 | ring_buffer_record_enable(buffer); | |
1042 | ||
a2f80714 SR |
1043 | arch_spin_unlock(&ftrace_max_lock); |
1044 | ||
0f048701 SR |
1045 | ftrace_start(); |
1046 | out: | |
2b6080f2 SR |
1047 | raw_spin_unlock_irqrestore(&global_trace.start_lock, flags); |
1048 | } | |
1049 | ||
1050 | static void tracing_start_tr(struct trace_array *tr) | |
1051 | { | |
1052 | struct ring_buffer *buffer; | |
1053 | unsigned long flags; | |
1054 | ||
1055 | if (tracing_disabled) | |
1056 | return; | |
1057 | ||
1058 | /* If global, we need to also start the max tracer */ | |
1059 | if (tr->flags & TRACE_ARRAY_FL_GLOBAL) | |
1060 | return tracing_start(); | |
1061 | ||
1062 | raw_spin_lock_irqsave(&tr->start_lock, flags); | |
1063 | ||
1064 | if (--tr->stop_count) { | |
1065 | if (tr->stop_count < 0) { | |
1066 | /* Someone screwed up their debugging */ | |
1067 | WARN_ON_ONCE(1); | |
1068 | tr->stop_count = 0; | |
1069 | } | |
1070 | goto out; | |
1071 | } | |
1072 | ||
1073 | buffer = tr->buffer; | |
1074 | if (buffer) | |
1075 | ring_buffer_record_enable(buffer); | |
1076 | ||
1077 | out: | |
1078 | raw_spin_unlock_irqrestore(&tr->start_lock, flags); | |
0f048701 SR |
1079 | } |
1080 | ||
1081 | /** | |
1082 | * tracing_stop - quick stop of the tracer | |
1083 | * | |
1084 | * Light weight way to stop tracing. Use in conjunction with | |
1085 | * tracing_start. | |
1086 | */ | |
1087 | void tracing_stop(void) | |
1088 | { | |
1089 | struct ring_buffer *buffer; | |
1090 | unsigned long flags; | |
1091 | ||
1092 | ftrace_stop(); | |
2b6080f2 SR |
1093 | raw_spin_lock_irqsave(&global_trace.start_lock, flags); |
1094 | if (global_trace.stop_count++) | |
0f048701 SR |
1095 | goto out; |
1096 | ||
a2f80714 SR |
1097 | /* Prevent the buffers from switching */ |
1098 | arch_spin_lock(&ftrace_max_lock); | |
1099 | ||
0f048701 SR |
1100 | buffer = global_trace.buffer; |
1101 | if (buffer) | |
1102 | ring_buffer_record_disable(buffer); | |
1103 | ||
1104 | buffer = max_tr.buffer; | |
1105 | if (buffer) | |
1106 | ring_buffer_record_disable(buffer); | |
1107 | ||
a2f80714 SR |
1108 | arch_spin_unlock(&ftrace_max_lock); |
1109 | ||
0f048701 | 1110 | out: |
2b6080f2 SR |
1111 | raw_spin_unlock_irqrestore(&global_trace.start_lock, flags); |
1112 | } | |
1113 | ||
1114 | static void tracing_stop_tr(struct trace_array *tr) | |
1115 | { | |
1116 | struct ring_buffer *buffer; | |
1117 | unsigned long flags; | |
1118 | ||
1119 | /* If global, we need to also stop the max tracer */ | |
1120 | if (tr->flags & TRACE_ARRAY_FL_GLOBAL) | |
1121 | return tracing_stop(); | |
1122 | ||
1123 | raw_spin_lock_irqsave(&tr->start_lock, flags); | |
1124 | if (tr->stop_count++) | |
1125 | goto out; | |
1126 | ||
1127 | buffer = tr->buffer; | |
1128 | if (buffer) | |
1129 | ring_buffer_record_disable(buffer); | |
1130 | ||
1131 | out: | |
1132 | raw_spin_unlock_irqrestore(&tr->start_lock, flags); | |
0f048701 SR |
1133 | } |
1134 | ||
e309b41d | 1135 | void trace_stop_cmdline_recording(void); |
bc0c38d1 | 1136 | |
e309b41d | 1137 | static void trace_save_cmdline(struct task_struct *tsk) |
bc0c38d1 | 1138 | { |
a635cf04 | 1139 | unsigned pid, idx; |
bc0c38d1 SR |
1140 | |
1141 | if (!tsk->pid || unlikely(tsk->pid > PID_MAX_DEFAULT)) | |
1142 | return; | |
1143 | ||
1144 | /* | |
1145 | * It's not the end of the world if we don't get | |
1146 | * the lock, but we also don't want to spin | |
1147 | * nor do we want to disable interrupts, | |
1148 | * so if we miss here, then better luck next time. | |
1149 | */ | |
0199c4e6 | 1150 | if (!arch_spin_trylock(&trace_cmdline_lock)) |
bc0c38d1 SR |
1151 | return; |
1152 | ||
1153 | idx = map_pid_to_cmdline[tsk->pid]; | |
2c7eea4c | 1154 | if (idx == NO_CMDLINE_MAP) { |
bc0c38d1 SR |
1155 | idx = (cmdline_idx + 1) % SAVED_CMDLINES; |
1156 | ||
a635cf04 CE |
1157 | /* |
1158 | * Check whether the cmdline buffer at idx has a pid | |
1159 | * mapped. We are going to overwrite that entry so we | |
1160 | * need to clear the map_pid_to_cmdline. Otherwise we | |
1161 | * would read the new comm for the old pid. | |
1162 | */ | |
1163 | pid = map_cmdline_to_pid[idx]; | |
1164 | if (pid != NO_CMDLINE_MAP) | |
1165 | map_pid_to_cmdline[pid] = NO_CMDLINE_MAP; | |
bc0c38d1 | 1166 | |
a635cf04 | 1167 | map_cmdline_to_pid[idx] = tsk->pid; |
bc0c38d1 SR |
1168 | map_pid_to_cmdline[tsk->pid] = idx; |
1169 | ||
1170 | cmdline_idx = idx; | |
1171 | } | |
1172 | ||
1173 | memcpy(&saved_cmdlines[idx], tsk->comm, TASK_COMM_LEN); | |
1174 | ||
0199c4e6 | 1175 | arch_spin_unlock(&trace_cmdline_lock); |
bc0c38d1 SR |
1176 | } |
1177 | ||
4ca53085 | 1178 | void trace_find_cmdline(int pid, char comm[]) |
bc0c38d1 | 1179 | { |
bc0c38d1 SR |
1180 | unsigned map; |
1181 | ||
4ca53085 SR |
1182 | if (!pid) { |
1183 | strcpy(comm, "<idle>"); | |
1184 | return; | |
1185 | } | |
bc0c38d1 | 1186 | |
74bf4076 SR |
1187 | if (WARN_ON_ONCE(pid < 0)) { |
1188 | strcpy(comm, "<XXX>"); | |
1189 | return; | |
1190 | } | |
1191 | ||
4ca53085 SR |
1192 | if (pid > PID_MAX_DEFAULT) { |
1193 | strcpy(comm, "<...>"); | |
1194 | return; | |
1195 | } | |
bc0c38d1 | 1196 | |
5b6045a9 | 1197 | preempt_disable(); |
0199c4e6 | 1198 | arch_spin_lock(&trace_cmdline_lock); |
bc0c38d1 | 1199 | map = map_pid_to_cmdline[pid]; |
50d88758 TG |
1200 | if (map != NO_CMDLINE_MAP) |
1201 | strcpy(comm, saved_cmdlines[map]); | |
1202 | else | |
1203 | strcpy(comm, "<...>"); | |
bc0c38d1 | 1204 | |
0199c4e6 | 1205 | arch_spin_unlock(&trace_cmdline_lock); |
5b6045a9 | 1206 | preempt_enable(); |
bc0c38d1 SR |
1207 | } |
1208 | ||
e309b41d | 1209 | void tracing_record_cmdline(struct task_struct *tsk) |
bc0c38d1 | 1210 | { |
0fb9656d | 1211 | if (atomic_read(&trace_record_cmdline_disabled) || !tracing_is_on()) |
bc0c38d1 SR |
1212 | return; |
1213 | ||
7ffbd48d SR |
1214 | if (!__this_cpu_read(trace_cmdline_save)) |
1215 | return; | |
1216 | ||
1217 | __this_cpu_write(trace_cmdline_save, false); | |
1218 | ||
bc0c38d1 SR |
1219 | trace_save_cmdline(tsk); |
1220 | } | |
1221 | ||
45dcd8b8 | 1222 | void |
38697053 SR |
1223 | tracing_generic_entry_update(struct trace_entry *entry, unsigned long flags, |
1224 | int pc) | |
bc0c38d1 SR |
1225 | { |
1226 | struct task_struct *tsk = current; | |
bc0c38d1 | 1227 | |
777e208d SR |
1228 | entry->preempt_count = pc & 0xff; |
1229 | entry->pid = (tsk) ? tsk->pid : 0; | |
1230 | entry->flags = | |
9244489a | 1231 | #ifdef CONFIG_TRACE_IRQFLAGS_SUPPORT |
2e2ca155 | 1232 | (irqs_disabled_flags(flags) ? TRACE_FLAG_IRQS_OFF : 0) | |
9244489a SR |
1233 | #else |
1234 | TRACE_FLAG_IRQS_NOSUPPORT | | |
1235 | #endif | |
bc0c38d1 SR |
1236 | ((pc & HARDIRQ_MASK) ? TRACE_FLAG_HARDIRQ : 0) | |
1237 | ((pc & SOFTIRQ_MASK) ? TRACE_FLAG_SOFTIRQ : 0) | | |
1238 | (need_resched() ? TRACE_FLAG_NEED_RESCHED : 0); | |
1239 | } | |
f413cdb8 | 1240 | EXPORT_SYMBOL_GPL(tracing_generic_entry_update); |
bc0c38d1 | 1241 | |
e77405ad SR |
1242 | struct ring_buffer_event * |
1243 | trace_buffer_lock_reserve(struct ring_buffer *buffer, | |
1244 | int type, | |
1245 | unsigned long len, | |
1246 | unsigned long flags, int pc) | |
51a763dd ACM |
1247 | { |
1248 | struct ring_buffer_event *event; | |
1249 | ||
e77405ad | 1250 | event = ring_buffer_lock_reserve(buffer, len); |
51a763dd ACM |
1251 | if (event != NULL) { |
1252 | struct trace_entry *ent = ring_buffer_event_data(event); | |
1253 | ||
1254 | tracing_generic_entry_update(ent, flags, pc); | |
1255 | ent->type = type; | |
1256 | } | |
1257 | ||
1258 | return event; | |
1259 | } | |
51a763dd | 1260 | |
7ffbd48d SR |
1261 | void |
1262 | __buffer_unlock_commit(struct ring_buffer *buffer, struct ring_buffer_event *event) | |
1263 | { | |
1264 | __this_cpu_write(trace_cmdline_save, true); | |
0d5c6e1c SR |
1265 | if (trace_wakeup_needed) { |
1266 | trace_wakeup_needed = false; | |
1267 | /* irq_work_queue() supplies it's own memory barriers */ | |
1268 | irq_work_queue(&trace_work_wakeup); | |
1269 | } | |
7ffbd48d SR |
1270 | ring_buffer_unlock_commit(buffer, event); |
1271 | } | |
1272 | ||
e77405ad SR |
1273 | static inline void |
1274 | __trace_buffer_unlock_commit(struct ring_buffer *buffer, | |
1275 | struct ring_buffer_event *event, | |
0d5c6e1c | 1276 | unsigned long flags, int pc) |
51a763dd | 1277 | { |
7ffbd48d | 1278 | __buffer_unlock_commit(buffer, event); |
51a763dd | 1279 | |
e77405ad SR |
1280 | ftrace_trace_stack(buffer, flags, 6, pc); |
1281 | ftrace_trace_userstack(buffer, flags, pc); | |
07edf712 FW |
1282 | } |
1283 | ||
e77405ad SR |
1284 | void trace_buffer_unlock_commit(struct ring_buffer *buffer, |
1285 | struct ring_buffer_event *event, | |
1286 | unsigned long flags, int pc) | |
07edf712 | 1287 | { |
0d5c6e1c | 1288 | __trace_buffer_unlock_commit(buffer, event, flags, pc); |
51a763dd | 1289 | } |
0d5c6e1c | 1290 | EXPORT_SYMBOL_GPL(trace_buffer_unlock_commit); |
51a763dd | 1291 | |
ccb469a1 SR |
1292 | struct ring_buffer_event * |
1293 | trace_event_buffer_lock_reserve(struct ring_buffer **current_rb, | |
1294 | struct ftrace_event_file *ftrace_file, | |
1295 | int type, unsigned long len, | |
1296 | unsigned long flags, int pc) | |
1297 | { | |
1298 | *current_rb = ftrace_file->tr->buffer; | |
1299 | return trace_buffer_lock_reserve(*current_rb, | |
1300 | type, len, flags, pc); | |
1301 | } | |
1302 | EXPORT_SYMBOL_GPL(trace_event_buffer_lock_reserve); | |
1303 | ||
ef5580d0 | 1304 | struct ring_buffer_event * |
e77405ad SR |
1305 | trace_current_buffer_lock_reserve(struct ring_buffer **current_rb, |
1306 | int type, unsigned long len, | |
ef5580d0 SR |
1307 | unsigned long flags, int pc) |
1308 | { | |
e77405ad SR |
1309 | *current_rb = global_trace.buffer; |
1310 | return trace_buffer_lock_reserve(*current_rb, | |
ef5580d0 SR |
1311 | type, len, flags, pc); |
1312 | } | |
94487d6d | 1313 | EXPORT_SYMBOL_GPL(trace_current_buffer_lock_reserve); |
ef5580d0 | 1314 | |
e77405ad SR |
1315 | void trace_current_buffer_unlock_commit(struct ring_buffer *buffer, |
1316 | struct ring_buffer_event *event, | |
ef5580d0 SR |
1317 | unsigned long flags, int pc) |
1318 | { | |
0d5c6e1c | 1319 | __trace_buffer_unlock_commit(buffer, event, flags, pc); |
07edf712 | 1320 | } |
94487d6d | 1321 | EXPORT_SYMBOL_GPL(trace_current_buffer_unlock_commit); |
07edf712 | 1322 | |
0d5c6e1c SR |
1323 | void trace_buffer_unlock_commit_regs(struct ring_buffer *buffer, |
1324 | struct ring_buffer_event *event, | |
1325 | unsigned long flags, int pc, | |
1326 | struct pt_regs *regs) | |
1fd8df2c | 1327 | { |
7ffbd48d | 1328 | __buffer_unlock_commit(buffer, event); |
1fd8df2c MH |
1329 | |
1330 | ftrace_trace_stack_regs(buffer, flags, 0, pc, regs); | |
1331 | ftrace_trace_userstack(buffer, flags, pc); | |
1332 | } | |
0d5c6e1c | 1333 | EXPORT_SYMBOL_GPL(trace_buffer_unlock_commit_regs); |
1fd8df2c | 1334 | |
e77405ad SR |
1335 | void trace_current_buffer_discard_commit(struct ring_buffer *buffer, |
1336 | struct ring_buffer_event *event) | |
77d9f465 | 1337 | { |
e77405ad | 1338 | ring_buffer_discard_commit(buffer, event); |
ef5580d0 | 1339 | } |
12acd473 | 1340 | EXPORT_SYMBOL_GPL(trace_current_buffer_discard_commit); |
ef5580d0 | 1341 | |
e309b41d | 1342 | void |
7be42151 | 1343 | trace_function(struct trace_array *tr, |
38697053 SR |
1344 | unsigned long ip, unsigned long parent_ip, unsigned long flags, |
1345 | int pc) | |
bc0c38d1 | 1346 | { |
e1112b4d | 1347 | struct ftrace_event_call *call = &event_function; |
e77405ad | 1348 | struct ring_buffer *buffer = tr->buffer; |
3928a8a2 | 1349 | struct ring_buffer_event *event; |
777e208d | 1350 | struct ftrace_entry *entry; |
bc0c38d1 | 1351 | |
d769041f | 1352 | /* If we are reading the ring buffer, don't trace */ |
dd17c8f7 | 1353 | if (unlikely(__this_cpu_read(ftrace_cpu_disabled))) |
d769041f SR |
1354 | return; |
1355 | ||
e77405ad | 1356 | event = trace_buffer_lock_reserve(buffer, TRACE_FN, sizeof(*entry), |
51a763dd | 1357 | flags, pc); |
3928a8a2 SR |
1358 | if (!event) |
1359 | return; | |
1360 | entry = ring_buffer_event_data(event); | |
777e208d SR |
1361 | entry->ip = ip; |
1362 | entry->parent_ip = parent_ip; | |
e1112b4d | 1363 | |
e77405ad | 1364 | if (!filter_check_discard(call, entry, buffer, event)) |
7ffbd48d | 1365 | __buffer_unlock_commit(buffer, event); |
bc0c38d1 SR |
1366 | } |
1367 | ||
e309b41d | 1368 | void |
2e0f5761 | 1369 | ftrace(struct trace_array *tr, struct trace_array_cpu *data, |
38697053 SR |
1370 | unsigned long ip, unsigned long parent_ip, unsigned long flags, |
1371 | int pc) | |
2e0f5761 IM |
1372 | { |
1373 | if (likely(!atomic_read(&data->disabled))) | |
7be42151 | 1374 | trace_function(tr, ip, parent_ip, flags, pc); |
2e0f5761 IM |
1375 | } |
1376 | ||
c0a0d0d3 | 1377 | #ifdef CONFIG_STACKTRACE |
4a9bd3f1 SR |
1378 | |
1379 | #define FTRACE_STACK_MAX_ENTRIES (PAGE_SIZE / sizeof(unsigned long)) | |
1380 | struct ftrace_stack { | |
1381 | unsigned long calls[FTRACE_STACK_MAX_ENTRIES]; | |
1382 | }; | |
1383 | ||
1384 | static DEFINE_PER_CPU(struct ftrace_stack, ftrace_stack); | |
1385 | static DEFINE_PER_CPU(int, ftrace_stack_reserve); | |
1386 | ||
e77405ad | 1387 | static void __ftrace_trace_stack(struct ring_buffer *buffer, |
53614991 | 1388 | unsigned long flags, |
1fd8df2c | 1389 | int skip, int pc, struct pt_regs *regs) |
86387f7e | 1390 | { |
e1112b4d | 1391 | struct ftrace_event_call *call = &event_kernel_stack; |
3928a8a2 | 1392 | struct ring_buffer_event *event; |
777e208d | 1393 | struct stack_entry *entry; |
86387f7e | 1394 | struct stack_trace trace; |
4a9bd3f1 SR |
1395 | int use_stack; |
1396 | int size = FTRACE_STACK_ENTRIES; | |
1397 | ||
1398 | trace.nr_entries = 0; | |
1399 | trace.skip = skip; | |
1400 | ||
1401 | /* | |
1402 | * Since events can happen in NMIs there's no safe way to | |
1403 | * use the per cpu ftrace_stacks. We reserve it and if an interrupt | |
1404 | * or NMI comes in, it will just have to use the default | |
1405 | * FTRACE_STACK_SIZE. | |
1406 | */ | |
1407 | preempt_disable_notrace(); | |
1408 | ||
82146529 | 1409 | use_stack = __this_cpu_inc_return(ftrace_stack_reserve); |
4a9bd3f1 SR |
1410 | /* |
1411 | * We don't need any atomic variables, just a barrier. | |
1412 | * If an interrupt comes in, we don't care, because it would | |
1413 | * have exited and put the counter back to what we want. | |
1414 | * We just need a barrier to keep gcc from moving things | |
1415 | * around. | |
1416 | */ | |
1417 | barrier(); | |
1418 | if (use_stack == 1) { | |
1419 | trace.entries = &__get_cpu_var(ftrace_stack).calls[0]; | |
1420 | trace.max_entries = FTRACE_STACK_MAX_ENTRIES; | |
1421 | ||
1422 | if (regs) | |
1423 | save_stack_trace_regs(regs, &trace); | |
1424 | else | |
1425 | save_stack_trace(&trace); | |
1426 | ||
1427 | if (trace.nr_entries > size) | |
1428 | size = trace.nr_entries; | |
1429 | } else | |
1430 | /* From now on, use_stack is a boolean */ | |
1431 | use_stack = 0; | |
1432 | ||
1433 | size *= sizeof(unsigned long); | |
86387f7e | 1434 | |
e77405ad | 1435 | event = trace_buffer_lock_reserve(buffer, TRACE_STACK, |
4a9bd3f1 | 1436 | sizeof(*entry) + size, flags, pc); |
3928a8a2 | 1437 | if (!event) |
4a9bd3f1 SR |
1438 | goto out; |
1439 | entry = ring_buffer_event_data(event); | |
86387f7e | 1440 | |
4a9bd3f1 SR |
1441 | memset(&entry->caller, 0, size); |
1442 | ||
1443 | if (use_stack) | |
1444 | memcpy(&entry->caller, trace.entries, | |
1445 | trace.nr_entries * sizeof(unsigned long)); | |
1446 | else { | |
1447 | trace.max_entries = FTRACE_STACK_ENTRIES; | |
1448 | trace.entries = entry->caller; | |
1449 | if (regs) | |
1450 | save_stack_trace_regs(regs, &trace); | |
1451 | else | |
1452 | save_stack_trace(&trace); | |
1453 | } | |
1454 | ||
1455 | entry->size = trace.nr_entries; | |
86387f7e | 1456 | |
e77405ad | 1457 | if (!filter_check_discard(call, entry, buffer, event)) |
7ffbd48d | 1458 | __buffer_unlock_commit(buffer, event); |
4a9bd3f1 SR |
1459 | |
1460 | out: | |
1461 | /* Again, don't let gcc optimize things here */ | |
1462 | barrier(); | |
82146529 | 1463 | __this_cpu_dec(ftrace_stack_reserve); |
4a9bd3f1 SR |
1464 | preempt_enable_notrace(); |
1465 | ||
f0a920d5 IM |
1466 | } |
1467 | ||
1fd8df2c MH |
1468 | void ftrace_trace_stack_regs(struct ring_buffer *buffer, unsigned long flags, |
1469 | int skip, int pc, struct pt_regs *regs) | |
1470 | { | |
1471 | if (!(trace_flags & TRACE_ITER_STACKTRACE)) | |
1472 | return; | |
1473 | ||
1474 | __ftrace_trace_stack(buffer, flags, skip, pc, regs); | |
1475 | } | |
1476 | ||
e77405ad SR |
1477 | void ftrace_trace_stack(struct ring_buffer *buffer, unsigned long flags, |
1478 | int skip, int pc) | |
53614991 SR |
1479 | { |
1480 | if (!(trace_flags & TRACE_ITER_STACKTRACE)) | |
1481 | return; | |
1482 | ||
1fd8df2c | 1483 | __ftrace_trace_stack(buffer, flags, skip, pc, NULL); |
53614991 SR |
1484 | } |
1485 | ||
c0a0d0d3 FW |
1486 | void __trace_stack(struct trace_array *tr, unsigned long flags, int skip, |
1487 | int pc) | |
38697053 | 1488 | { |
1fd8df2c | 1489 | __ftrace_trace_stack(tr->buffer, flags, skip, pc, NULL); |
38697053 SR |
1490 | } |
1491 | ||
03889384 SR |
1492 | /** |
1493 | * trace_dump_stack - record a stack back trace in the trace buffer | |
1494 | */ | |
1495 | void trace_dump_stack(void) | |
1496 | { | |
1497 | unsigned long flags; | |
1498 | ||
1499 | if (tracing_disabled || tracing_selftest_running) | |
e36c5458 | 1500 | return; |
03889384 SR |
1501 | |
1502 | local_save_flags(flags); | |
1503 | ||
1504 | /* skipping 3 traces, seems to get us at the caller of this function */ | |
1fd8df2c | 1505 | __ftrace_trace_stack(global_trace.buffer, flags, 3, preempt_count(), NULL); |
03889384 SR |
1506 | } |
1507 | ||
91e86e56 SR |
1508 | static DEFINE_PER_CPU(int, user_stack_count); |
1509 | ||
e77405ad SR |
1510 | void |
1511 | ftrace_trace_userstack(struct ring_buffer *buffer, unsigned long flags, int pc) | |
02b67518 | 1512 | { |
e1112b4d | 1513 | struct ftrace_event_call *call = &event_user_stack; |
8d7c6a96 | 1514 | struct ring_buffer_event *event; |
02b67518 TE |
1515 | struct userstack_entry *entry; |
1516 | struct stack_trace trace; | |
02b67518 TE |
1517 | |
1518 | if (!(trace_flags & TRACE_ITER_USERSTACKTRACE)) | |
1519 | return; | |
1520 | ||
b6345879 SR |
1521 | /* |
1522 | * NMIs can not handle page faults, even with fix ups. | |
1523 | * The save user stack can (and often does) fault. | |
1524 | */ | |
1525 | if (unlikely(in_nmi())) | |
1526 | return; | |
02b67518 | 1527 | |
91e86e56 SR |
1528 | /* |
1529 | * prevent recursion, since the user stack tracing may | |
1530 | * trigger other kernel events. | |
1531 | */ | |
1532 | preempt_disable(); | |
1533 | if (__this_cpu_read(user_stack_count)) | |
1534 | goto out; | |
1535 | ||
1536 | __this_cpu_inc(user_stack_count); | |
1537 | ||
e77405ad | 1538 | event = trace_buffer_lock_reserve(buffer, TRACE_USER_STACK, |
51a763dd | 1539 | sizeof(*entry), flags, pc); |
02b67518 | 1540 | if (!event) |
1dbd1951 | 1541 | goto out_drop_count; |
02b67518 | 1542 | entry = ring_buffer_event_data(event); |
02b67518 | 1543 | |
48659d31 | 1544 | entry->tgid = current->tgid; |
02b67518 TE |
1545 | memset(&entry->caller, 0, sizeof(entry->caller)); |
1546 | ||
1547 | trace.nr_entries = 0; | |
1548 | trace.max_entries = FTRACE_STACK_ENTRIES; | |
1549 | trace.skip = 0; | |
1550 | trace.entries = entry->caller; | |
1551 | ||
1552 | save_stack_trace_user(&trace); | |
e77405ad | 1553 | if (!filter_check_discard(call, entry, buffer, event)) |
7ffbd48d | 1554 | __buffer_unlock_commit(buffer, event); |
91e86e56 | 1555 | |
1dbd1951 | 1556 | out_drop_count: |
91e86e56 | 1557 | __this_cpu_dec(user_stack_count); |
91e86e56 SR |
1558 | out: |
1559 | preempt_enable(); | |
02b67518 TE |
1560 | } |
1561 | ||
4fd27358 HE |
1562 | #ifdef UNUSED |
1563 | static void __trace_userstack(struct trace_array *tr, unsigned long flags) | |
02b67518 | 1564 | { |
7be42151 | 1565 | ftrace_trace_userstack(tr, flags, preempt_count()); |
02b67518 | 1566 | } |
4fd27358 | 1567 | #endif /* UNUSED */ |
02b67518 | 1568 | |
c0a0d0d3 FW |
1569 | #endif /* CONFIG_STACKTRACE */ |
1570 | ||
07d777fe SR |
1571 | /* created for use with alloc_percpu */ |
1572 | struct trace_buffer_struct { | |
1573 | char buffer[TRACE_BUF_SIZE]; | |
1574 | }; | |
1575 | ||
1576 | static struct trace_buffer_struct *trace_percpu_buffer; | |
1577 | static struct trace_buffer_struct *trace_percpu_sirq_buffer; | |
1578 | static struct trace_buffer_struct *trace_percpu_irq_buffer; | |
1579 | static struct trace_buffer_struct *trace_percpu_nmi_buffer; | |
1580 | ||
1581 | /* | |
1582 | * The buffer used is dependent on the context. There is a per cpu | |
1583 | * buffer for normal context, softirq contex, hard irq context and | |
1584 | * for NMI context. Thise allows for lockless recording. | |
1585 | * | |
1586 | * Note, if the buffers failed to be allocated, then this returns NULL | |
1587 | */ | |
1588 | static char *get_trace_buf(void) | |
1589 | { | |
1590 | struct trace_buffer_struct *percpu_buffer; | |
07d777fe SR |
1591 | |
1592 | /* | |
1593 | * If we have allocated per cpu buffers, then we do not | |
1594 | * need to do any locking. | |
1595 | */ | |
1596 | if (in_nmi()) | |
1597 | percpu_buffer = trace_percpu_nmi_buffer; | |
1598 | else if (in_irq()) | |
1599 | percpu_buffer = trace_percpu_irq_buffer; | |
1600 | else if (in_softirq()) | |
1601 | percpu_buffer = trace_percpu_sirq_buffer; | |
1602 | else | |
1603 | percpu_buffer = trace_percpu_buffer; | |
1604 | ||
1605 | if (!percpu_buffer) | |
1606 | return NULL; | |
1607 | ||
d8a0349c | 1608 | return this_cpu_ptr(&percpu_buffer->buffer[0]); |
07d777fe SR |
1609 | } |
1610 | ||
1611 | static int alloc_percpu_trace_buffer(void) | |
1612 | { | |
1613 | struct trace_buffer_struct *buffers; | |
1614 | struct trace_buffer_struct *sirq_buffers; | |
1615 | struct trace_buffer_struct *irq_buffers; | |
1616 | struct trace_buffer_struct *nmi_buffers; | |
1617 | ||
1618 | buffers = alloc_percpu(struct trace_buffer_struct); | |
1619 | if (!buffers) | |
1620 | goto err_warn; | |
1621 | ||
1622 | sirq_buffers = alloc_percpu(struct trace_buffer_struct); | |
1623 | if (!sirq_buffers) | |
1624 | goto err_sirq; | |
1625 | ||
1626 | irq_buffers = alloc_percpu(struct trace_buffer_struct); | |
1627 | if (!irq_buffers) | |
1628 | goto err_irq; | |
1629 | ||
1630 | nmi_buffers = alloc_percpu(struct trace_buffer_struct); | |
1631 | if (!nmi_buffers) | |
1632 | goto err_nmi; | |
1633 | ||
1634 | trace_percpu_buffer = buffers; | |
1635 | trace_percpu_sirq_buffer = sirq_buffers; | |
1636 | trace_percpu_irq_buffer = irq_buffers; | |
1637 | trace_percpu_nmi_buffer = nmi_buffers; | |
1638 | ||
1639 | return 0; | |
1640 | ||
1641 | err_nmi: | |
1642 | free_percpu(irq_buffers); | |
1643 | err_irq: | |
1644 | free_percpu(sirq_buffers); | |
1645 | err_sirq: | |
1646 | free_percpu(buffers); | |
1647 | err_warn: | |
1648 | WARN(1, "Could not allocate percpu trace_printk buffer"); | |
1649 | return -ENOMEM; | |
1650 | } | |
1651 | ||
81698831 SR |
1652 | static int buffers_allocated; |
1653 | ||
07d777fe SR |
1654 | void trace_printk_init_buffers(void) |
1655 | { | |
07d777fe SR |
1656 | if (buffers_allocated) |
1657 | return; | |
1658 | ||
1659 | if (alloc_percpu_trace_buffer()) | |
1660 | return; | |
1661 | ||
1662 | pr_info("ftrace: Allocated trace_printk buffers\n"); | |
1663 | ||
b382ede6 SR |
1664 | /* Expand the buffers to set size */ |
1665 | tracing_update_buffers(); | |
1666 | ||
07d777fe | 1667 | buffers_allocated = 1; |
81698831 SR |
1668 | |
1669 | /* | |
1670 | * trace_printk_init_buffers() can be called by modules. | |
1671 | * If that happens, then we need to start cmdline recording | |
1672 | * directly here. If the global_trace.buffer is already | |
1673 | * allocated here, then this was called by module code. | |
1674 | */ | |
1675 | if (global_trace.buffer) | |
1676 | tracing_start_cmdline_record(); | |
1677 | } | |
1678 | ||
1679 | void trace_printk_start_comm(void) | |
1680 | { | |
1681 | /* Start tracing comms if trace printk is set */ | |
1682 | if (!buffers_allocated) | |
1683 | return; | |
1684 | tracing_start_cmdline_record(); | |
1685 | } | |
1686 | ||
1687 | static void trace_printk_start_stop_comm(int enabled) | |
1688 | { | |
1689 | if (!buffers_allocated) | |
1690 | return; | |
1691 | ||
1692 | if (enabled) | |
1693 | tracing_start_cmdline_record(); | |
1694 | else | |
1695 | tracing_stop_cmdline_record(); | |
07d777fe SR |
1696 | } |
1697 | ||
769b0441 | 1698 | /** |
48ead020 | 1699 | * trace_vbprintk - write binary msg to tracing buffer |
769b0441 FW |
1700 | * |
1701 | */ | |
40ce74f1 | 1702 | int trace_vbprintk(unsigned long ip, const char *fmt, va_list args) |
769b0441 | 1703 | { |
e1112b4d | 1704 | struct ftrace_event_call *call = &event_bprint; |
769b0441 | 1705 | struct ring_buffer_event *event; |
e77405ad | 1706 | struct ring_buffer *buffer; |
769b0441 | 1707 | struct trace_array *tr = &global_trace; |
48ead020 | 1708 | struct bprint_entry *entry; |
769b0441 | 1709 | unsigned long flags; |
07d777fe SR |
1710 | char *tbuffer; |
1711 | int len = 0, size, pc; | |
769b0441 FW |
1712 | |
1713 | if (unlikely(tracing_selftest_running || tracing_disabled)) | |
1714 | return 0; | |
1715 | ||
1716 | /* Don't pollute graph traces with trace_vprintk internals */ | |
1717 | pause_graph_tracing(); | |
1718 | ||
1719 | pc = preempt_count(); | |
5168ae50 | 1720 | preempt_disable_notrace(); |
769b0441 | 1721 | |
07d777fe SR |
1722 | tbuffer = get_trace_buf(); |
1723 | if (!tbuffer) { | |
1724 | len = 0; | |
769b0441 | 1725 | goto out; |
07d777fe | 1726 | } |
769b0441 | 1727 | |
07d777fe | 1728 | len = vbin_printf((u32 *)tbuffer, TRACE_BUF_SIZE/sizeof(int), fmt, args); |
769b0441 | 1729 | |
07d777fe SR |
1730 | if (len > TRACE_BUF_SIZE/sizeof(int) || len < 0) |
1731 | goto out; | |
769b0441 | 1732 | |
07d777fe | 1733 | local_save_flags(flags); |
769b0441 | 1734 | size = sizeof(*entry) + sizeof(u32) * len; |
e77405ad SR |
1735 | buffer = tr->buffer; |
1736 | event = trace_buffer_lock_reserve(buffer, TRACE_BPRINT, size, | |
1737 | flags, pc); | |
769b0441 | 1738 | if (!event) |
07d777fe | 1739 | goto out; |
769b0441 FW |
1740 | entry = ring_buffer_event_data(event); |
1741 | entry->ip = ip; | |
769b0441 FW |
1742 | entry->fmt = fmt; |
1743 | ||
07d777fe | 1744 | memcpy(entry->buf, tbuffer, sizeof(u32) * len); |
d931369b | 1745 | if (!filter_check_discard(call, entry, buffer, event)) { |
7ffbd48d | 1746 | __buffer_unlock_commit(buffer, event); |
d931369b SR |
1747 | ftrace_trace_stack(buffer, flags, 6, pc); |
1748 | } | |
769b0441 | 1749 | |
769b0441 | 1750 | out: |
5168ae50 | 1751 | preempt_enable_notrace(); |
769b0441 FW |
1752 | unpause_graph_tracing(); |
1753 | ||
1754 | return len; | |
1755 | } | |
48ead020 FW |
1756 | EXPORT_SYMBOL_GPL(trace_vbprintk); |
1757 | ||
659372d3 SR |
1758 | int trace_array_printk(struct trace_array *tr, |
1759 | unsigned long ip, const char *fmt, ...) | |
1760 | { | |
1761 | int ret; | |
1762 | va_list ap; | |
1763 | ||
1764 | if (!(trace_flags & TRACE_ITER_PRINTK)) | |
1765 | return 0; | |
1766 | ||
1767 | va_start(ap, fmt); | |
1768 | ret = trace_array_vprintk(tr, ip, fmt, ap); | |
1769 | va_end(ap); | |
1770 | return ret; | |
1771 | } | |
1772 | ||
1773 | int trace_array_vprintk(struct trace_array *tr, | |
1774 | unsigned long ip, const char *fmt, va_list args) | |
48ead020 | 1775 | { |
e1112b4d | 1776 | struct ftrace_event_call *call = &event_print; |
48ead020 | 1777 | struct ring_buffer_event *event; |
e77405ad | 1778 | struct ring_buffer *buffer; |
07d777fe | 1779 | int len = 0, size, pc; |
48ead020 | 1780 | struct print_entry *entry; |
07d777fe SR |
1781 | unsigned long flags; |
1782 | char *tbuffer; | |
48ead020 FW |
1783 | |
1784 | if (tracing_disabled || tracing_selftest_running) | |
1785 | return 0; | |
1786 | ||
07d777fe SR |
1787 | /* Don't pollute graph traces with trace_vprintk internals */ |
1788 | pause_graph_tracing(); | |
1789 | ||
48ead020 FW |
1790 | pc = preempt_count(); |
1791 | preempt_disable_notrace(); | |
48ead020 | 1792 | |
07d777fe SR |
1793 | |
1794 | tbuffer = get_trace_buf(); | |
1795 | if (!tbuffer) { | |
1796 | len = 0; | |
48ead020 | 1797 | goto out; |
07d777fe | 1798 | } |
48ead020 | 1799 | |
07d777fe SR |
1800 | len = vsnprintf(tbuffer, TRACE_BUF_SIZE, fmt, args); |
1801 | if (len > TRACE_BUF_SIZE) | |
1802 | goto out; | |
48ead020 | 1803 | |
07d777fe | 1804 | local_save_flags(flags); |
48ead020 | 1805 | size = sizeof(*entry) + len + 1; |
e77405ad SR |
1806 | buffer = tr->buffer; |
1807 | event = trace_buffer_lock_reserve(buffer, TRACE_PRINT, size, | |
07d777fe | 1808 | flags, pc); |
48ead020 | 1809 | if (!event) |
07d777fe | 1810 | goto out; |
48ead020 | 1811 | entry = ring_buffer_event_data(event); |
c13d2f7c | 1812 | entry->ip = ip; |
48ead020 | 1813 | |
07d777fe | 1814 | memcpy(&entry->buf, tbuffer, len); |
c13d2f7c | 1815 | entry->buf[len] = '\0'; |
d931369b | 1816 | if (!filter_check_discard(call, entry, buffer, event)) { |
7ffbd48d | 1817 | __buffer_unlock_commit(buffer, event); |
07d777fe | 1818 | ftrace_trace_stack(buffer, flags, 6, pc); |
d931369b | 1819 | } |
48ead020 FW |
1820 | out: |
1821 | preempt_enable_notrace(); | |
07d777fe | 1822 | unpause_graph_tracing(); |
48ead020 FW |
1823 | |
1824 | return len; | |
1825 | } | |
659372d3 SR |
1826 | |
1827 | int trace_vprintk(unsigned long ip, const char *fmt, va_list args) | |
1828 | { | |
a813a159 | 1829 | return trace_array_vprintk(&global_trace, ip, fmt, args); |
659372d3 | 1830 | } |
769b0441 FW |
1831 | EXPORT_SYMBOL_GPL(trace_vprintk); |
1832 | ||
e2ac8ef5 | 1833 | static void trace_iterator_increment(struct trace_iterator *iter) |
5a90f577 | 1834 | { |
6d158a81 SR |
1835 | struct ring_buffer_iter *buf_iter = trace_buffer_iter(iter, iter->cpu); |
1836 | ||
5a90f577 | 1837 | iter->idx++; |
6d158a81 SR |
1838 | if (buf_iter) |
1839 | ring_buffer_read(buf_iter, NULL); | |
5a90f577 SR |
1840 | } |
1841 | ||
e309b41d | 1842 | static struct trace_entry * |
bc21b478 SR |
1843 | peek_next_entry(struct trace_iterator *iter, int cpu, u64 *ts, |
1844 | unsigned long *lost_events) | |
dd0e545f | 1845 | { |
3928a8a2 | 1846 | struct ring_buffer_event *event; |
6d158a81 | 1847 | struct ring_buffer_iter *buf_iter = trace_buffer_iter(iter, cpu); |
dd0e545f | 1848 | |
d769041f SR |
1849 | if (buf_iter) |
1850 | event = ring_buffer_iter_peek(buf_iter, ts); | |
1851 | else | |
bc21b478 SR |
1852 | event = ring_buffer_peek(iter->tr->buffer, cpu, ts, |
1853 | lost_events); | |
d769041f | 1854 | |
4a9bd3f1 SR |
1855 | if (event) { |
1856 | iter->ent_size = ring_buffer_event_length(event); | |
1857 | return ring_buffer_event_data(event); | |
1858 | } | |
1859 | iter->ent_size = 0; | |
1860 | return NULL; | |
dd0e545f | 1861 | } |
d769041f | 1862 | |
dd0e545f | 1863 | static struct trace_entry * |
bc21b478 SR |
1864 | __find_next_entry(struct trace_iterator *iter, int *ent_cpu, |
1865 | unsigned long *missing_events, u64 *ent_ts) | |
bc0c38d1 | 1866 | { |
3928a8a2 | 1867 | struct ring_buffer *buffer = iter->tr->buffer; |
bc0c38d1 | 1868 | struct trace_entry *ent, *next = NULL; |
aa27497c | 1869 | unsigned long lost_events = 0, next_lost = 0; |
b04cc6b1 | 1870 | int cpu_file = iter->cpu_file; |
3928a8a2 | 1871 | u64 next_ts = 0, ts; |
bc0c38d1 | 1872 | int next_cpu = -1; |
12b5da34 | 1873 | int next_size = 0; |
bc0c38d1 SR |
1874 | int cpu; |
1875 | ||
b04cc6b1 FW |
1876 | /* |
1877 | * If we are in a per_cpu trace file, don't bother by iterating over | |
1878 | * all cpu and peek directly. | |
1879 | */ | |
ae3b5093 | 1880 | if (cpu_file > RING_BUFFER_ALL_CPUS) { |
b04cc6b1 FW |
1881 | if (ring_buffer_empty_cpu(buffer, cpu_file)) |
1882 | return NULL; | |
bc21b478 | 1883 | ent = peek_next_entry(iter, cpu_file, ent_ts, missing_events); |
b04cc6b1 FW |
1884 | if (ent_cpu) |
1885 | *ent_cpu = cpu_file; | |
1886 | ||
1887 | return ent; | |
1888 | } | |
1889 | ||
ab46428c | 1890 | for_each_tracing_cpu(cpu) { |
dd0e545f | 1891 | |
3928a8a2 SR |
1892 | if (ring_buffer_empty_cpu(buffer, cpu)) |
1893 | continue; | |
dd0e545f | 1894 | |
bc21b478 | 1895 | ent = peek_next_entry(iter, cpu, &ts, &lost_events); |
dd0e545f | 1896 | |
cdd31cd2 IM |
1897 | /* |
1898 | * Pick the entry with the smallest timestamp: | |
1899 | */ | |
3928a8a2 | 1900 | if (ent && (!next || ts < next_ts)) { |
bc0c38d1 SR |
1901 | next = ent; |
1902 | next_cpu = cpu; | |
3928a8a2 | 1903 | next_ts = ts; |
bc21b478 | 1904 | next_lost = lost_events; |
12b5da34 | 1905 | next_size = iter->ent_size; |
bc0c38d1 SR |
1906 | } |
1907 | } | |
1908 | ||
12b5da34 SR |
1909 | iter->ent_size = next_size; |
1910 | ||
bc0c38d1 SR |
1911 | if (ent_cpu) |
1912 | *ent_cpu = next_cpu; | |
1913 | ||
3928a8a2 SR |
1914 | if (ent_ts) |
1915 | *ent_ts = next_ts; | |
1916 | ||
bc21b478 SR |
1917 | if (missing_events) |
1918 | *missing_events = next_lost; | |
1919 | ||
bc0c38d1 SR |
1920 | return next; |
1921 | } | |
1922 | ||
dd0e545f | 1923 | /* Find the next real entry, without updating the iterator itself */ |
c4a8e8be FW |
1924 | struct trace_entry *trace_find_next_entry(struct trace_iterator *iter, |
1925 | int *ent_cpu, u64 *ent_ts) | |
bc0c38d1 | 1926 | { |
bc21b478 | 1927 | return __find_next_entry(iter, ent_cpu, NULL, ent_ts); |
dd0e545f SR |
1928 | } |
1929 | ||
1930 | /* Find the next real entry, and increment the iterator to the next entry */ | |
955b61e5 | 1931 | void *trace_find_next_entry_inc(struct trace_iterator *iter) |
dd0e545f | 1932 | { |
bc21b478 SR |
1933 | iter->ent = __find_next_entry(iter, &iter->cpu, |
1934 | &iter->lost_events, &iter->ts); | |
dd0e545f | 1935 | |
3928a8a2 | 1936 | if (iter->ent) |
e2ac8ef5 | 1937 | trace_iterator_increment(iter); |
dd0e545f | 1938 | |
3928a8a2 | 1939 | return iter->ent ? iter : NULL; |
b3806b43 | 1940 | } |
bc0c38d1 | 1941 | |
e309b41d | 1942 | static void trace_consume(struct trace_iterator *iter) |
b3806b43 | 1943 | { |
bc21b478 SR |
1944 | ring_buffer_consume(iter->tr->buffer, iter->cpu, &iter->ts, |
1945 | &iter->lost_events); | |
bc0c38d1 SR |
1946 | } |
1947 | ||
e309b41d | 1948 | static void *s_next(struct seq_file *m, void *v, loff_t *pos) |
bc0c38d1 SR |
1949 | { |
1950 | struct trace_iterator *iter = m->private; | |
bc0c38d1 | 1951 | int i = (int)*pos; |
4e3c3333 | 1952 | void *ent; |
bc0c38d1 | 1953 | |
a63ce5b3 SR |
1954 | WARN_ON_ONCE(iter->leftover); |
1955 | ||
bc0c38d1 SR |
1956 | (*pos)++; |
1957 | ||
1958 | /* can't go backwards */ | |
1959 | if (iter->idx > i) | |
1960 | return NULL; | |
1961 | ||
1962 | if (iter->idx < 0) | |
955b61e5 | 1963 | ent = trace_find_next_entry_inc(iter); |
bc0c38d1 SR |
1964 | else |
1965 | ent = iter; | |
1966 | ||
1967 | while (ent && iter->idx < i) | |
955b61e5 | 1968 | ent = trace_find_next_entry_inc(iter); |
bc0c38d1 SR |
1969 | |
1970 | iter->pos = *pos; | |
1971 | ||
bc0c38d1 SR |
1972 | return ent; |
1973 | } | |
1974 | ||
955b61e5 | 1975 | void tracing_iter_reset(struct trace_iterator *iter, int cpu) |
2f26ebd5 SR |
1976 | { |
1977 | struct trace_array *tr = iter->tr; | |
1978 | struct ring_buffer_event *event; | |
1979 | struct ring_buffer_iter *buf_iter; | |
1980 | unsigned long entries = 0; | |
1981 | u64 ts; | |
1982 | ||
a7603ff4 | 1983 | per_cpu_ptr(tr->data, cpu)->skipped_entries = 0; |
2f26ebd5 | 1984 | |
6d158a81 SR |
1985 | buf_iter = trace_buffer_iter(iter, cpu); |
1986 | if (!buf_iter) | |
2f26ebd5 SR |
1987 | return; |
1988 | ||
2f26ebd5 SR |
1989 | ring_buffer_iter_reset(buf_iter); |
1990 | ||
1991 | /* | |
1992 | * We could have the case with the max latency tracers | |
1993 | * that a reset never took place on a cpu. This is evident | |
1994 | * by the timestamp being before the start of the buffer. | |
1995 | */ | |
1996 | while ((event = ring_buffer_iter_peek(buf_iter, &ts))) { | |
1997 | if (ts >= iter->tr->time_start) | |
1998 | break; | |
1999 | entries++; | |
2000 | ring_buffer_read(buf_iter, NULL); | |
2001 | } | |
2002 | ||
a7603ff4 | 2003 | per_cpu_ptr(tr->data, cpu)->skipped_entries = entries; |
2f26ebd5 SR |
2004 | } |
2005 | ||
d7350c3f | 2006 | /* |
d7350c3f FW |
2007 | * The current tracer is copied to avoid a global locking |
2008 | * all around. | |
2009 | */ | |
bc0c38d1 SR |
2010 | static void *s_start(struct seq_file *m, loff_t *pos) |
2011 | { | |
2012 | struct trace_iterator *iter = m->private; | |
2b6080f2 | 2013 | struct trace_array *tr = iter->tr; |
b04cc6b1 | 2014 | int cpu_file = iter->cpu_file; |
bc0c38d1 SR |
2015 | void *p = NULL; |
2016 | loff_t l = 0; | |
3928a8a2 | 2017 | int cpu; |
bc0c38d1 | 2018 | |
2fd196ec HT |
2019 | /* |
2020 | * copy the tracer to avoid using a global lock all around. | |
2021 | * iter->trace is a copy of current_trace, the pointer to the | |
2022 | * name may be used instead of a strcmp(), as iter->trace->name | |
2023 | * will point to the same string as current_trace->name. | |
2024 | */ | |
bc0c38d1 | 2025 | mutex_lock(&trace_types_lock); |
2b6080f2 SR |
2026 | if (unlikely(tr->current_trace && iter->trace->name != tr->current_trace->name)) |
2027 | *iter->trace = *tr->current_trace; | |
d7350c3f | 2028 | mutex_unlock(&trace_types_lock); |
bc0c38d1 | 2029 | |
debdd57f HT |
2030 | if (iter->snapshot && iter->trace->use_max_tr) |
2031 | return ERR_PTR(-EBUSY); | |
2032 | ||
2033 | if (!iter->snapshot) | |
2034 | atomic_inc(&trace_record_cmdline_disabled); | |
bc0c38d1 | 2035 | |
bc0c38d1 SR |
2036 | if (*pos != iter->pos) { |
2037 | iter->ent = NULL; | |
2038 | iter->cpu = 0; | |
2039 | iter->idx = -1; | |
2040 | ||
ae3b5093 | 2041 | if (cpu_file == RING_BUFFER_ALL_CPUS) { |
b04cc6b1 | 2042 | for_each_tracing_cpu(cpu) |
2f26ebd5 | 2043 | tracing_iter_reset(iter, cpu); |
b04cc6b1 | 2044 | } else |
2f26ebd5 | 2045 | tracing_iter_reset(iter, cpu_file); |
bc0c38d1 | 2046 | |
ac91d854 | 2047 | iter->leftover = 0; |
bc0c38d1 SR |
2048 | for (p = iter; p && l < *pos; p = s_next(m, p, &l)) |
2049 | ; | |
2050 | ||
2051 | } else { | |
a63ce5b3 SR |
2052 | /* |
2053 | * If we overflowed the seq_file before, then we want | |
2054 | * to just reuse the trace_seq buffer again. | |
2055 | */ | |
2056 | if (iter->leftover) | |
2057 | p = iter; | |
2058 | else { | |
2059 | l = *pos - 1; | |
2060 | p = s_next(m, p, &l); | |
2061 | } | |
bc0c38d1 SR |
2062 | } |
2063 | ||
4f535968 | 2064 | trace_event_read_lock(); |
7e53bd42 | 2065 | trace_access_lock(cpu_file); |
bc0c38d1 SR |
2066 | return p; |
2067 | } | |
2068 | ||
2069 | static void s_stop(struct seq_file *m, void *p) | |
2070 | { | |
7e53bd42 LJ |
2071 | struct trace_iterator *iter = m->private; |
2072 | ||
debdd57f HT |
2073 | if (iter->snapshot && iter->trace->use_max_tr) |
2074 | return; | |
2075 | ||
2076 | if (!iter->snapshot) | |
2077 | atomic_dec(&trace_record_cmdline_disabled); | |
7e53bd42 | 2078 | trace_access_unlock(iter->cpu_file); |
4f535968 | 2079 | trace_event_read_unlock(); |
bc0c38d1 SR |
2080 | } |
2081 | ||
39eaf7ef SR |
2082 | static void |
2083 | get_total_entries(struct trace_array *tr, unsigned long *total, unsigned long *entries) | |
2084 | { | |
2085 | unsigned long count; | |
2086 | int cpu; | |
2087 | ||
2088 | *total = 0; | |
2089 | *entries = 0; | |
2090 | ||
2091 | for_each_tracing_cpu(cpu) { | |
2092 | count = ring_buffer_entries_cpu(tr->buffer, cpu); | |
2093 | /* | |
2094 | * If this buffer has skipped entries, then we hold all | |
2095 | * entries for the trace and we need to ignore the | |
2096 | * ones before the time stamp. | |
2097 | */ | |
a7603ff4 SR |
2098 | if (per_cpu_ptr(tr->data, cpu)->skipped_entries) { |
2099 | count -= per_cpu_ptr(tr->data, cpu)->skipped_entries; | |
39eaf7ef SR |
2100 | /* total is the same as the entries */ |
2101 | *total += count; | |
2102 | } else | |
2103 | *total += count + | |
2104 | ring_buffer_overrun_cpu(tr->buffer, cpu); | |
2105 | *entries += count; | |
2106 | } | |
2107 | } | |
2108 | ||
e309b41d | 2109 | static void print_lat_help_header(struct seq_file *m) |
bc0c38d1 | 2110 | { |
a6168353 ME |
2111 | seq_puts(m, "# _------=> CPU# \n"); |
2112 | seq_puts(m, "# / _-----=> irqs-off \n"); | |
2113 | seq_puts(m, "# | / _----=> need-resched \n"); | |
2114 | seq_puts(m, "# || / _---=> hardirq/softirq \n"); | |
2115 | seq_puts(m, "# ||| / _--=> preempt-depth \n"); | |
e6e1e259 SR |
2116 | seq_puts(m, "# |||| / delay \n"); |
2117 | seq_puts(m, "# cmd pid ||||| time | caller \n"); | |
2118 | seq_puts(m, "# \\ / ||||| \\ | / \n"); | |
bc0c38d1 SR |
2119 | } |
2120 | ||
39eaf7ef | 2121 | static void print_event_info(struct trace_array *tr, struct seq_file *m) |
bc0c38d1 | 2122 | { |
39eaf7ef SR |
2123 | unsigned long total; |
2124 | unsigned long entries; | |
2125 | ||
2126 | get_total_entries(tr, &total, &entries); | |
2127 | seq_printf(m, "# entries-in-buffer/entries-written: %lu/%lu #P:%d\n", | |
2128 | entries, total, num_online_cpus()); | |
2129 | seq_puts(m, "#\n"); | |
2130 | } | |
2131 | ||
2132 | static void print_func_help_header(struct trace_array *tr, struct seq_file *m) | |
2133 | { | |
2134 | print_event_info(tr, m); | |
77271ce4 | 2135 | seq_puts(m, "# TASK-PID CPU# TIMESTAMP FUNCTION\n"); |
a6168353 | 2136 | seq_puts(m, "# | | | | |\n"); |
bc0c38d1 SR |
2137 | } |
2138 | ||
39eaf7ef | 2139 | static void print_func_help_header_irq(struct trace_array *tr, struct seq_file *m) |
77271ce4 | 2140 | { |
39eaf7ef | 2141 | print_event_info(tr, m); |
77271ce4 SR |
2142 | seq_puts(m, "# _-----=> irqs-off\n"); |
2143 | seq_puts(m, "# / _----=> need-resched\n"); | |
2144 | seq_puts(m, "# | / _---=> hardirq/softirq\n"); | |
2145 | seq_puts(m, "# || / _--=> preempt-depth\n"); | |
2146 | seq_puts(m, "# ||| / delay\n"); | |
2147 | seq_puts(m, "# TASK-PID CPU# |||| TIMESTAMP FUNCTION\n"); | |
2148 | seq_puts(m, "# | | | |||| | |\n"); | |
2149 | } | |
bc0c38d1 | 2150 | |
62b915f1 | 2151 | void |
bc0c38d1 SR |
2152 | print_trace_header(struct seq_file *m, struct trace_iterator *iter) |
2153 | { | |
2154 | unsigned long sym_flags = (trace_flags & TRACE_ITER_SYM_MASK); | |
2155 | struct trace_array *tr = iter->tr; | |
a7603ff4 | 2156 | struct trace_array_cpu *data = per_cpu_ptr(tr->data, tr->cpu); |
2b6080f2 | 2157 | struct tracer *type = iter->trace; |
39eaf7ef SR |
2158 | unsigned long entries; |
2159 | unsigned long total; | |
bc0c38d1 SR |
2160 | const char *name = "preemption"; |
2161 | ||
d840f718 | 2162 | name = type->name; |
bc0c38d1 | 2163 | |
39eaf7ef | 2164 | get_total_entries(tr, &total, &entries); |
bc0c38d1 | 2165 | |
888b55dc | 2166 | seq_printf(m, "# %s latency trace v1.1.5 on %s\n", |
bc0c38d1 | 2167 | name, UTS_RELEASE); |
888b55dc | 2168 | seq_puts(m, "# -----------------------------------" |
bc0c38d1 | 2169 | "---------------------------------\n"); |
888b55dc | 2170 | seq_printf(m, "# latency: %lu us, #%lu/%lu, CPU#%d |" |
bc0c38d1 | 2171 | " (M:%s VP:%d, KP:%d, SP:%d HP:%d", |
57f50be1 | 2172 | nsecs_to_usecs(data->saved_latency), |
bc0c38d1 | 2173 | entries, |
4c11d7ae | 2174 | total, |
bc0c38d1 SR |
2175 | tr->cpu, |
2176 | #if defined(CONFIG_PREEMPT_NONE) | |
2177 | "server", | |
2178 | #elif defined(CONFIG_PREEMPT_VOLUNTARY) | |
2179 | "desktop", | |
b5c21b45 | 2180 | #elif defined(CONFIG_PREEMPT) |
bc0c38d1 SR |
2181 | "preempt", |
2182 | #else | |
2183 | "unknown", | |
2184 | #endif | |
2185 | /* These are reserved for later use */ | |
2186 | 0, 0, 0, 0); | |
2187 | #ifdef CONFIG_SMP | |
2188 | seq_printf(m, " #P:%d)\n", num_online_cpus()); | |
2189 | #else | |
2190 | seq_puts(m, ")\n"); | |
2191 | #endif | |
888b55dc KM |
2192 | seq_puts(m, "# -----------------\n"); |
2193 | seq_printf(m, "# | task: %.16s-%d " | |
bc0c38d1 | 2194 | "(uid:%d nice:%ld policy:%ld rt_prio:%ld)\n", |
d20b92ab EB |
2195 | data->comm, data->pid, |
2196 | from_kuid_munged(seq_user_ns(m), data->uid), data->nice, | |
bc0c38d1 | 2197 | data->policy, data->rt_priority); |
888b55dc | 2198 | seq_puts(m, "# -----------------\n"); |
bc0c38d1 SR |
2199 | |
2200 | if (data->critical_start) { | |
888b55dc | 2201 | seq_puts(m, "# => started at: "); |
214023c3 SR |
2202 | seq_print_ip_sym(&iter->seq, data->critical_start, sym_flags); |
2203 | trace_print_seq(m, &iter->seq); | |
888b55dc | 2204 | seq_puts(m, "\n# => ended at: "); |
214023c3 SR |
2205 | seq_print_ip_sym(&iter->seq, data->critical_end, sym_flags); |
2206 | trace_print_seq(m, &iter->seq); | |
8248ac05 | 2207 | seq_puts(m, "\n#\n"); |
bc0c38d1 SR |
2208 | } |
2209 | ||
888b55dc | 2210 | seq_puts(m, "#\n"); |
bc0c38d1 SR |
2211 | } |
2212 | ||
a309720c SR |
2213 | static void test_cpu_buff_start(struct trace_iterator *iter) |
2214 | { | |
2215 | struct trace_seq *s = &iter->seq; | |
2216 | ||
12ef7d44 SR |
2217 | if (!(trace_flags & TRACE_ITER_ANNOTATE)) |
2218 | return; | |
2219 | ||
2220 | if (!(iter->iter_flags & TRACE_FILE_ANNOTATE)) | |
2221 | return; | |
2222 | ||
4462344e | 2223 | if (cpumask_test_cpu(iter->cpu, iter->started)) |
a309720c SR |
2224 | return; |
2225 | ||
a7603ff4 | 2226 | if (per_cpu_ptr(iter->tr->data, iter->cpu)->skipped_entries) |
2f26ebd5 SR |
2227 | return; |
2228 | ||
4462344e | 2229 | cpumask_set_cpu(iter->cpu, iter->started); |
b0dfa978 FW |
2230 | |
2231 | /* Don't print started cpu buffer for the first entry of the trace */ | |
2232 | if (iter->idx > 1) | |
2233 | trace_seq_printf(s, "##### CPU %u buffer started ####\n", | |
2234 | iter->cpu); | |
a309720c SR |
2235 | } |
2236 | ||
2c4f035f | 2237 | static enum print_line_t print_trace_fmt(struct trace_iterator *iter) |
bc0c38d1 | 2238 | { |
214023c3 | 2239 | struct trace_seq *s = &iter->seq; |
bc0c38d1 | 2240 | unsigned long sym_flags = (trace_flags & TRACE_ITER_SYM_MASK); |
4e3c3333 | 2241 | struct trace_entry *entry; |
f633cef0 | 2242 | struct trace_event *event; |
bc0c38d1 | 2243 | |
4e3c3333 | 2244 | entry = iter->ent; |
dd0e545f | 2245 | |
a309720c SR |
2246 | test_cpu_buff_start(iter); |
2247 | ||
c4a8e8be | 2248 | event = ftrace_find_event(entry->type); |
bc0c38d1 | 2249 | |
c4a8e8be | 2250 | if (trace_flags & TRACE_ITER_CONTEXT_INFO) { |
27d48be8 SR |
2251 | if (iter->iter_flags & TRACE_FILE_LAT_FMT) { |
2252 | if (!trace_print_lat_context(iter)) | |
2253 | goto partial; | |
2254 | } else { | |
2255 | if (!trace_print_context(iter)) | |
2256 | goto partial; | |
2257 | } | |
c4a8e8be | 2258 | } |
bc0c38d1 | 2259 | |
268ccda0 | 2260 | if (event) |
a9a57763 | 2261 | return event->funcs->trace(iter, sym_flags, event); |
d9793bd8 ACM |
2262 | |
2263 | if (!trace_seq_printf(s, "Unknown type %d\n", entry->type)) | |
2264 | goto partial; | |
02b67518 | 2265 | |
2c4f035f | 2266 | return TRACE_TYPE_HANDLED; |
d9793bd8 ACM |
2267 | partial: |
2268 | return TRACE_TYPE_PARTIAL_LINE; | |
bc0c38d1 SR |
2269 | } |
2270 | ||
2c4f035f | 2271 | static enum print_line_t print_raw_fmt(struct trace_iterator *iter) |
f9896bf3 IM |
2272 | { |
2273 | struct trace_seq *s = &iter->seq; | |
2274 | struct trace_entry *entry; | |
f633cef0 | 2275 | struct trace_event *event; |
f9896bf3 IM |
2276 | |
2277 | entry = iter->ent; | |
dd0e545f | 2278 | |
c4a8e8be | 2279 | if (trace_flags & TRACE_ITER_CONTEXT_INFO) { |
d9793bd8 ACM |
2280 | if (!trace_seq_printf(s, "%d %d %llu ", |
2281 | entry->pid, iter->cpu, iter->ts)) | |
2282 | goto partial; | |
c4a8e8be | 2283 | } |
f9896bf3 | 2284 | |
f633cef0 | 2285 | event = ftrace_find_event(entry->type); |
268ccda0 | 2286 | if (event) |
a9a57763 | 2287 | return event->funcs->raw(iter, 0, event); |
d9793bd8 ACM |
2288 | |
2289 | if (!trace_seq_printf(s, "%d ?\n", entry->type)) | |
2290 | goto partial; | |
777e208d | 2291 | |
2c4f035f | 2292 | return TRACE_TYPE_HANDLED; |
d9793bd8 ACM |
2293 | partial: |
2294 | return TRACE_TYPE_PARTIAL_LINE; | |
f9896bf3 IM |
2295 | } |
2296 | ||
2c4f035f | 2297 | static enum print_line_t print_hex_fmt(struct trace_iterator *iter) |
5e3ca0ec IM |
2298 | { |
2299 | struct trace_seq *s = &iter->seq; | |
2300 | unsigned char newline = '\n'; | |
2301 | struct trace_entry *entry; | |
f633cef0 | 2302 | struct trace_event *event; |
5e3ca0ec IM |
2303 | |
2304 | entry = iter->ent; | |
dd0e545f | 2305 | |
c4a8e8be FW |
2306 | if (trace_flags & TRACE_ITER_CONTEXT_INFO) { |
2307 | SEQ_PUT_HEX_FIELD_RET(s, entry->pid); | |
2308 | SEQ_PUT_HEX_FIELD_RET(s, iter->cpu); | |
2309 | SEQ_PUT_HEX_FIELD_RET(s, iter->ts); | |
2310 | } | |
5e3ca0ec | 2311 | |
f633cef0 | 2312 | event = ftrace_find_event(entry->type); |
268ccda0 | 2313 | if (event) { |
a9a57763 | 2314 | enum print_line_t ret = event->funcs->hex(iter, 0, event); |
d9793bd8 ACM |
2315 | if (ret != TRACE_TYPE_HANDLED) |
2316 | return ret; | |
2317 | } | |
7104f300 | 2318 | |
5e3ca0ec IM |
2319 | SEQ_PUT_FIELD_RET(s, newline); |
2320 | ||
2c4f035f | 2321 | return TRACE_TYPE_HANDLED; |
5e3ca0ec IM |
2322 | } |
2323 | ||
2c4f035f | 2324 | static enum print_line_t print_bin_fmt(struct trace_iterator *iter) |
cb0f12aa IM |
2325 | { |
2326 | struct trace_seq *s = &iter->seq; | |
2327 | struct trace_entry *entry; | |
f633cef0 | 2328 | struct trace_event *event; |
cb0f12aa IM |
2329 | |
2330 | entry = iter->ent; | |
dd0e545f | 2331 | |
c4a8e8be FW |
2332 | if (trace_flags & TRACE_ITER_CONTEXT_INFO) { |
2333 | SEQ_PUT_FIELD_RET(s, entry->pid); | |
1830b52d | 2334 | SEQ_PUT_FIELD_RET(s, iter->cpu); |
c4a8e8be FW |
2335 | SEQ_PUT_FIELD_RET(s, iter->ts); |
2336 | } | |
cb0f12aa | 2337 | |
f633cef0 | 2338 | event = ftrace_find_event(entry->type); |
a9a57763 SR |
2339 | return event ? event->funcs->binary(iter, 0, event) : |
2340 | TRACE_TYPE_HANDLED; | |
cb0f12aa IM |
2341 | } |
2342 | ||
62b915f1 | 2343 | int trace_empty(struct trace_iterator *iter) |
bc0c38d1 | 2344 | { |
6d158a81 | 2345 | struct ring_buffer_iter *buf_iter; |
bc0c38d1 SR |
2346 | int cpu; |
2347 | ||
9aba60fe | 2348 | /* If we are looking at one CPU buffer, only check that one */ |
ae3b5093 | 2349 | if (iter->cpu_file != RING_BUFFER_ALL_CPUS) { |
9aba60fe | 2350 | cpu = iter->cpu_file; |
6d158a81 SR |
2351 | buf_iter = trace_buffer_iter(iter, cpu); |
2352 | if (buf_iter) { | |
2353 | if (!ring_buffer_iter_empty(buf_iter)) | |
9aba60fe SR |
2354 | return 0; |
2355 | } else { | |
2356 | if (!ring_buffer_empty_cpu(iter->tr->buffer, cpu)) | |
2357 | return 0; | |
2358 | } | |
2359 | return 1; | |
2360 | } | |
2361 | ||
ab46428c | 2362 | for_each_tracing_cpu(cpu) { |
6d158a81 SR |
2363 | buf_iter = trace_buffer_iter(iter, cpu); |
2364 | if (buf_iter) { | |
2365 | if (!ring_buffer_iter_empty(buf_iter)) | |
d769041f SR |
2366 | return 0; |
2367 | } else { | |
2368 | if (!ring_buffer_empty_cpu(iter->tr->buffer, cpu)) | |
2369 | return 0; | |
2370 | } | |
bc0c38d1 | 2371 | } |
d769041f | 2372 | |
797d3712 | 2373 | return 1; |
bc0c38d1 SR |
2374 | } |
2375 | ||
4f535968 | 2376 | /* Called with trace_event_read_lock() held. */ |
955b61e5 | 2377 | enum print_line_t print_trace_line(struct trace_iterator *iter) |
f9896bf3 | 2378 | { |
2c4f035f FW |
2379 | enum print_line_t ret; |
2380 | ||
ee5e51f5 JO |
2381 | if (iter->lost_events && |
2382 | !trace_seq_printf(&iter->seq, "CPU:%d [LOST %lu EVENTS]\n", | |
2383 | iter->cpu, iter->lost_events)) | |
2384 | return TRACE_TYPE_PARTIAL_LINE; | |
bc21b478 | 2385 | |
2c4f035f FW |
2386 | if (iter->trace && iter->trace->print_line) { |
2387 | ret = iter->trace->print_line(iter); | |
2388 | if (ret != TRACE_TYPE_UNHANDLED) | |
2389 | return ret; | |
2390 | } | |
72829bc3 | 2391 | |
48ead020 FW |
2392 | if (iter->ent->type == TRACE_BPRINT && |
2393 | trace_flags & TRACE_ITER_PRINTK && | |
2394 | trace_flags & TRACE_ITER_PRINTK_MSGONLY) | |
5ef841f6 | 2395 | return trace_print_bprintk_msg_only(iter); |
48ead020 | 2396 | |
66896a85 FW |
2397 | if (iter->ent->type == TRACE_PRINT && |
2398 | trace_flags & TRACE_ITER_PRINTK && | |
2399 | trace_flags & TRACE_ITER_PRINTK_MSGONLY) | |
5ef841f6 | 2400 | return trace_print_printk_msg_only(iter); |
66896a85 | 2401 | |
cb0f12aa IM |
2402 | if (trace_flags & TRACE_ITER_BIN) |
2403 | return print_bin_fmt(iter); | |
2404 | ||
5e3ca0ec IM |
2405 | if (trace_flags & TRACE_ITER_HEX) |
2406 | return print_hex_fmt(iter); | |
2407 | ||
f9896bf3 IM |
2408 | if (trace_flags & TRACE_ITER_RAW) |
2409 | return print_raw_fmt(iter); | |
2410 | ||
f9896bf3 IM |
2411 | return print_trace_fmt(iter); |
2412 | } | |
2413 | ||
7e9a49ef JO |
2414 | void trace_latency_header(struct seq_file *m) |
2415 | { | |
2416 | struct trace_iterator *iter = m->private; | |
2417 | ||
2418 | /* print nothing if the buffers are empty */ | |
2419 | if (trace_empty(iter)) | |
2420 | return; | |
2421 | ||
2422 | if (iter->iter_flags & TRACE_FILE_LAT_FMT) | |
2423 | print_trace_header(m, iter); | |
2424 | ||
2425 | if (!(trace_flags & TRACE_ITER_VERBOSE)) | |
2426 | print_lat_help_header(m); | |
2427 | } | |
2428 | ||
62b915f1 JO |
2429 | void trace_default_header(struct seq_file *m) |
2430 | { | |
2431 | struct trace_iterator *iter = m->private; | |
2432 | ||
f56e7f8e JO |
2433 | if (!(trace_flags & TRACE_ITER_CONTEXT_INFO)) |
2434 | return; | |
2435 | ||
62b915f1 JO |
2436 | if (iter->iter_flags & TRACE_FILE_LAT_FMT) { |
2437 | /* print nothing if the buffers are empty */ | |
2438 | if (trace_empty(iter)) | |
2439 | return; | |
2440 | print_trace_header(m, iter); | |
2441 | if (!(trace_flags & TRACE_ITER_VERBOSE)) | |
2442 | print_lat_help_header(m); | |
2443 | } else { | |
77271ce4 SR |
2444 | if (!(trace_flags & TRACE_ITER_VERBOSE)) { |
2445 | if (trace_flags & TRACE_ITER_IRQ_INFO) | |
39eaf7ef | 2446 | print_func_help_header_irq(iter->tr, m); |
77271ce4 | 2447 | else |
39eaf7ef | 2448 | print_func_help_header(iter->tr, m); |
77271ce4 | 2449 | } |
62b915f1 JO |
2450 | } |
2451 | } | |
2452 | ||
e0a413f6 SR |
2453 | static void test_ftrace_alive(struct seq_file *m) |
2454 | { | |
2455 | if (!ftrace_is_dead()) | |
2456 | return; | |
2457 | seq_printf(m, "# WARNING: FUNCTION TRACING IS CORRUPTED\n"); | |
2458 | seq_printf(m, "# MAY BE MISSING FUNCTION EVENTS\n"); | |
2459 | } | |
2460 | ||
d8741e2e SRRH |
2461 | #ifdef CONFIG_TRACER_MAX_TRACE |
2462 | static void print_snapshot_help(struct seq_file *m, struct trace_iterator *iter) | |
2463 | { | |
2464 | if (iter->trace->allocated_snapshot) | |
2465 | seq_printf(m, "#\n# * Snapshot is allocated *\n#\n"); | |
2466 | else | |
2467 | seq_printf(m, "#\n# * Snapshot is freed *\n#\n"); | |
2468 | ||
2469 | seq_printf(m, "# Snapshot commands:\n"); | |
2470 | seq_printf(m, "# echo 0 > snapshot : Clears and frees snapshot buffer\n"); | |
2471 | seq_printf(m, "# echo 1 > snapshot : Allocates snapshot buffer, if not already allocated.\n"); | |
2472 | seq_printf(m, "# Takes a snapshot of the main buffer.\n"); | |
2473 | seq_printf(m, "# echo 2 > snapshot : Clears snapshot buffer (but does not allocate)\n"); | |
2474 | seq_printf(m, "# (Doesn't have to be '2' works with any number that\n"); | |
2475 | seq_printf(m, "# is not a '0' or '1')\n"); | |
2476 | } | |
2477 | #else | |
2478 | /* Should never be called */ | |
2479 | static inline void print_snapshot_help(struct seq_file *m, struct trace_iterator *iter) { } | |
2480 | #endif | |
2481 | ||
bc0c38d1 SR |
2482 | static int s_show(struct seq_file *m, void *v) |
2483 | { | |
2484 | struct trace_iterator *iter = v; | |
a63ce5b3 | 2485 | int ret; |
bc0c38d1 SR |
2486 | |
2487 | if (iter->ent == NULL) { | |
2488 | if (iter->tr) { | |
2489 | seq_printf(m, "# tracer: %s\n", iter->trace->name); | |
2490 | seq_puts(m, "#\n"); | |
e0a413f6 | 2491 | test_ftrace_alive(m); |
bc0c38d1 | 2492 | } |
d8741e2e SRRH |
2493 | if (iter->snapshot && trace_empty(iter)) |
2494 | print_snapshot_help(m, iter); | |
2495 | else if (iter->trace && iter->trace->print_header) | |
8bba1bf5 | 2496 | iter->trace->print_header(m); |
62b915f1 JO |
2497 | else |
2498 | trace_default_header(m); | |
2499 | ||
a63ce5b3 SR |
2500 | } else if (iter->leftover) { |
2501 | /* | |
2502 | * If we filled the seq_file buffer earlier, we | |
2503 | * want to just show it now. | |
2504 | */ | |
2505 | ret = trace_print_seq(m, &iter->seq); | |
2506 | ||
2507 | /* ret should this time be zero, but you never know */ | |
2508 | iter->leftover = ret; | |
2509 | ||
bc0c38d1 | 2510 | } else { |
f9896bf3 | 2511 | print_trace_line(iter); |
a63ce5b3 SR |
2512 | ret = trace_print_seq(m, &iter->seq); |
2513 | /* | |
2514 | * If we overflow the seq_file buffer, then it will | |
2515 | * ask us for this data again at start up. | |
2516 | * Use that instead. | |
2517 | * ret is 0 if seq_file write succeeded. | |
2518 | * -1 otherwise. | |
2519 | */ | |
2520 | iter->leftover = ret; | |
bc0c38d1 SR |
2521 | } |
2522 | ||
2523 | return 0; | |
2524 | } | |
2525 | ||
88e9d34c | 2526 | static const struct seq_operations tracer_seq_ops = { |
4bf39a94 IM |
2527 | .start = s_start, |
2528 | .next = s_next, | |
2529 | .stop = s_stop, | |
2530 | .show = s_show, | |
bc0c38d1 SR |
2531 | }; |
2532 | ||
e309b41d | 2533 | static struct trace_iterator * |
debdd57f | 2534 | __tracing_open(struct inode *inode, struct file *file, bool snapshot) |
bc0c38d1 | 2535 | { |
2b6080f2 SR |
2536 | struct trace_cpu *tc = inode->i_private; |
2537 | struct trace_array *tr = tc->tr; | |
bc0c38d1 | 2538 | struct trace_iterator *iter; |
50e18b94 | 2539 | int cpu; |
bc0c38d1 | 2540 | |
85a2f9b4 SR |
2541 | if (tracing_disabled) |
2542 | return ERR_PTR(-ENODEV); | |
60a11774 | 2543 | |
50e18b94 | 2544 | iter = __seq_open_private(file, &tracer_seq_ops, sizeof(*iter)); |
85a2f9b4 SR |
2545 | if (!iter) |
2546 | return ERR_PTR(-ENOMEM); | |
bc0c38d1 | 2547 | |
6d158a81 SR |
2548 | iter->buffer_iter = kzalloc(sizeof(*iter->buffer_iter) * num_possible_cpus(), |
2549 | GFP_KERNEL); | |
93574fcc DC |
2550 | if (!iter->buffer_iter) |
2551 | goto release; | |
2552 | ||
d7350c3f FW |
2553 | /* |
2554 | * We make a copy of the current tracer to avoid concurrent | |
2555 | * changes on it while we are reading. | |
2556 | */ | |
bc0c38d1 | 2557 | mutex_lock(&trace_types_lock); |
d7350c3f | 2558 | iter->trace = kzalloc(sizeof(*iter->trace), GFP_KERNEL); |
85a2f9b4 | 2559 | if (!iter->trace) |
d7350c3f | 2560 | goto fail; |
85a2f9b4 | 2561 | |
2b6080f2 | 2562 | *iter->trace = *tr->current_trace; |
d7350c3f | 2563 | |
79f55997 | 2564 | if (!zalloc_cpumask_var(&iter->started, GFP_KERNEL)) |
b0dfa978 FW |
2565 | goto fail; |
2566 | ||
2b6080f2 SR |
2567 | /* Currently only the top directory has a snapshot */ |
2568 | if (tr->current_trace->print_max || snapshot) | |
bc0c38d1 SR |
2569 | iter->tr = &max_tr; |
2570 | else | |
2b6080f2 | 2571 | iter->tr = tr; |
debdd57f | 2572 | iter->snapshot = snapshot; |
bc0c38d1 | 2573 | iter->pos = -1; |
d7350c3f | 2574 | mutex_init(&iter->mutex); |
2b6080f2 | 2575 | iter->cpu_file = tc->cpu; |
bc0c38d1 | 2576 | |
8bba1bf5 MM |
2577 | /* Notify the tracer early; before we stop tracing. */ |
2578 | if (iter->trace && iter->trace->open) | |
a93751ca | 2579 | iter->trace->open(iter); |
8bba1bf5 | 2580 | |
12ef7d44 SR |
2581 | /* Annotate start of buffers if we had overruns */ |
2582 | if (ring_buffer_overruns(iter->tr->buffer)) | |
2583 | iter->iter_flags |= TRACE_FILE_ANNOTATE; | |
2584 | ||
8be0709f DS |
2585 | /* Output in nanoseconds only if we are using a clock in nanoseconds. */ |
2586 | if (trace_clocks[trace_clock_id].in_ns) | |
2587 | iter->iter_flags |= TRACE_FILE_TIME_IN_NS; | |
2588 | ||
debdd57f HT |
2589 | /* stop the trace while dumping if we are not opening "snapshot" */ |
2590 | if (!iter->snapshot) | |
2b6080f2 | 2591 | tracing_stop_tr(tr); |
2f26ebd5 | 2592 | |
ae3b5093 | 2593 | if (iter->cpu_file == RING_BUFFER_ALL_CPUS) { |
b04cc6b1 | 2594 | for_each_tracing_cpu(cpu) { |
b04cc6b1 | 2595 | iter->buffer_iter[cpu] = |
72c9ddfd DM |
2596 | ring_buffer_read_prepare(iter->tr->buffer, cpu); |
2597 | } | |
2598 | ring_buffer_read_prepare_sync(); | |
2599 | for_each_tracing_cpu(cpu) { | |
2600 | ring_buffer_read_start(iter->buffer_iter[cpu]); | |
2f26ebd5 | 2601 | tracing_iter_reset(iter, cpu); |
b04cc6b1 FW |
2602 | } |
2603 | } else { | |
2604 | cpu = iter->cpu_file; | |
3928a8a2 | 2605 | iter->buffer_iter[cpu] = |
72c9ddfd DM |
2606 | ring_buffer_read_prepare(iter->tr->buffer, cpu); |
2607 | ring_buffer_read_prepare_sync(); | |
2608 | ring_buffer_read_start(iter->buffer_iter[cpu]); | |
2f26ebd5 | 2609 | tracing_iter_reset(iter, cpu); |
3928a8a2 SR |
2610 | } |
2611 | ||
bc0c38d1 SR |
2612 | mutex_unlock(&trace_types_lock); |
2613 | ||
bc0c38d1 | 2614 | return iter; |
3928a8a2 | 2615 | |
d7350c3f | 2616 | fail: |
3928a8a2 | 2617 | mutex_unlock(&trace_types_lock); |
d7350c3f | 2618 | kfree(iter->trace); |
6d158a81 | 2619 | kfree(iter->buffer_iter); |
93574fcc | 2620 | release: |
50e18b94 JO |
2621 | seq_release_private(inode, file); |
2622 | return ERR_PTR(-ENOMEM); | |
bc0c38d1 SR |
2623 | } |
2624 | ||
2625 | int tracing_open_generic(struct inode *inode, struct file *filp) | |
2626 | { | |
60a11774 SR |
2627 | if (tracing_disabled) |
2628 | return -ENODEV; | |
2629 | ||
bc0c38d1 SR |
2630 | filp->private_data = inode->i_private; |
2631 | return 0; | |
2632 | } | |
2633 | ||
4fd27358 | 2634 | static int tracing_release(struct inode *inode, struct file *file) |
bc0c38d1 | 2635 | { |
907f2784 | 2636 | struct seq_file *m = file->private_data; |
4acd4d00 | 2637 | struct trace_iterator *iter; |
2b6080f2 | 2638 | struct trace_array *tr; |
3928a8a2 | 2639 | int cpu; |
bc0c38d1 | 2640 | |
4acd4d00 SR |
2641 | if (!(file->f_mode & FMODE_READ)) |
2642 | return 0; | |
2643 | ||
2644 | iter = m->private; | |
2645 | ||
2b6080f2 SR |
2646 | /* Only the global tracer has a matching max_tr */ |
2647 | if (iter->tr == &max_tr) | |
2648 | tr = &global_trace; | |
2649 | else | |
2650 | tr = iter->tr; | |
2651 | ||
bc0c38d1 | 2652 | mutex_lock(&trace_types_lock); |
3928a8a2 SR |
2653 | for_each_tracing_cpu(cpu) { |
2654 | if (iter->buffer_iter[cpu]) | |
2655 | ring_buffer_read_finish(iter->buffer_iter[cpu]); | |
2656 | } | |
2657 | ||
bc0c38d1 SR |
2658 | if (iter->trace && iter->trace->close) |
2659 | iter->trace->close(iter); | |
2660 | ||
debdd57f HT |
2661 | if (!iter->snapshot) |
2662 | /* reenable tracing if it was previously enabled */ | |
2b6080f2 | 2663 | tracing_start_tr(tr); |
bc0c38d1 SR |
2664 | mutex_unlock(&trace_types_lock); |
2665 | ||
d7350c3f | 2666 | mutex_destroy(&iter->mutex); |
b0dfa978 | 2667 | free_cpumask_var(iter->started); |
d7350c3f | 2668 | kfree(iter->trace); |
6d158a81 | 2669 | kfree(iter->buffer_iter); |
50e18b94 | 2670 | seq_release_private(inode, file); |
bc0c38d1 SR |
2671 | return 0; |
2672 | } | |
2673 | ||
2674 | static int tracing_open(struct inode *inode, struct file *file) | |
2675 | { | |
85a2f9b4 SR |
2676 | struct trace_iterator *iter; |
2677 | int ret = 0; | |
bc0c38d1 | 2678 | |
4acd4d00 SR |
2679 | /* If this file was open for write, then erase contents */ |
2680 | if ((file->f_mode & FMODE_WRITE) && | |
8650ae32 | 2681 | (file->f_flags & O_TRUNC)) { |
2b6080f2 SR |
2682 | struct trace_cpu *tc = inode->i_private; |
2683 | struct trace_array *tr = tc->tr; | |
bc0c38d1 | 2684 | |
2b6080f2 SR |
2685 | if (tc->cpu == RING_BUFFER_ALL_CPUS) |
2686 | tracing_reset_online_cpus(tr); | |
4acd4d00 | 2687 | else |
2b6080f2 | 2688 | tracing_reset(tr, tc->cpu); |
4acd4d00 | 2689 | } |
bc0c38d1 | 2690 | |
4acd4d00 | 2691 | if (file->f_mode & FMODE_READ) { |
debdd57f | 2692 | iter = __tracing_open(inode, file, false); |
4acd4d00 SR |
2693 | if (IS_ERR(iter)) |
2694 | ret = PTR_ERR(iter); | |
2695 | else if (trace_flags & TRACE_ITER_LATENCY_FMT) | |
2696 | iter->iter_flags |= TRACE_FILE_LAT_FMT; | |
2697 | } | |
bc0c38d1 SR |
2698 | return ret; |
2699 | } | |
2700 | ||
e309b41d | 2701 | static void * |
bc0c38d1 SR |
2702 | t_next(struct seq_file *m, void *v, loff_t *pos) |
2703 | { | |
f129e965 | 2704 | struct tracer *t = v; |
bc0c38d1 SR |
2705 | |
2706 | (*pos)++; | |
2707 | ||
2708 | if (t) | |
2709 | t = t->next; | |
2710 | ||
bc0c38d1 SR |
2711 | return t; |
2712 | } | |
2713 | ||
2714 | static void *t_start(struct seq_file *m, loff_t *pos) | |
2715 | { | |
f129e965 | 2716 | struct tracer *t; |
bc0c38d1 SR |
2717 | loff_t l = 0; |
2718 | ||
2719 | mutex_lock(&trace_types_lock); | |
f129e965 | 2720 | for (t = trace_types; t && l < *pos; t = t_next(m, t, &l)) |
bc0c38d1 SR |
2721 | ; |
2722 | ||
2723 | return t; | |
2724 | } | |
2725 | ||
2726 | static void t_stop(struct seq_file *m, void *p) | |
2727 | { | |
2728 | mutex_unlock(&trace_types_lock); | |
2729 | } | |
2730 | ||
2731 | static int t_show(struct seq_file *m, void *v) | |
2732 | { | |
2733 | struct tracer *t = v; | |
2734 | ||
2735 | if (!t) | |
2736 | return 0; | |
2737 | ||
2738 | seq_printf(m, "%s", t->name); | |
2739 | if (t->next) | |
2740 | seq_putc(m, ' '); | |
2741 | else | |
2742 | seq_putc(m, '\n'); | |
2743 | ||
2744 | return 0; | |
2745 | } | |
2746 | ||
88e9d34c | 2747 | static const struct seq_operations show_traces_seq_ops = { |
4bf39a94 IM |
2748 | .start = t_start, |
2749 | .next = t_next, | |
2750 | .stop = t_stop, | |
2751 | .show = t_show, | |
bc0c38d1 SR |
2752 | }; |
2753 | ||
2754 | static int show_traces_open(struct inode *inode, struct file *file) | |
2755 | { | |
60a11774 SR |
2756 | if (tracing_disabled) |
2757 | return -ENODEV; | |
2758 | ||
f129e965 | 2759 | return seq_open(file, &show_traces_seq_ops); |
bc0c38d1 SR |
2760 | } |
2761 | ||
4acd4d00 SR |
2762 | static ssize_t |
2763 | tracing_write_stub(struct file *filp, const char __user *ubuf, | |
2764 | size_t count, loff_t *ppos) | |
2765 | { | |
2766 | return count; | |
2767 | } | |
2768 | ||
364829b1 SP |
2769 | static loff_t tracing_seek(struct file *file, loff_t offset, int origin) |
2770 | { | |
2771 | if (file->f_mode & FMODE_READ) | |
2772 | return seq_lseek(file, offset, origin); | |
2773 | else | |
2774 | return 0; | |
2775 | } | |
2776 | ||
5e2336a0 | 2777 | static const struct file_operations tracing_fops = { |
4bf39a94 IM |
2778 | .open = tracing_open, |
2779 | .read = seq_read, | |
4acd4d00 | 2780 | .write = tracing_write_stub, |
364829b1 | 2781 | .llseek = tracing_seek, |
4bf39a94 | 2782 | .release = tracing_release, |
bc0c38d1 SR |
2783 | }; |
2784 | ||
5e2336a0 | 2785 | static const struct file_operations show_traces_fops = { |
c7078de1 IM |
2786 | .open = show_traces_open, |
2787 | .read = seq_read, | |
2788 | .release = seq_release, | |
b444786f | 2789 | .llseek = seq_lseek, |
c7078de1 IM |
2790 | }; |
2791 | ||
36dfe925 IM |
2792 | /* |
2793 | * Only trace on a CPU if the bitmask is set: | |
2794 | */ | |
9e01c1b7 | 2795 | static cpumask_var_t tracing_cpumask; |
36dfe925 IM |
2796 | |
2797 | /* | |
2798 | * The tracer itself will not take this lock, but still we want | |
2799 | * to provide a consistent cpumask to user-space: | |
2800 | */ | |
2801 | static DEFINE_MUTEX(tracing_cpumask_update_lock); | |
2802 | ||
2803 | /* | |
2804 | * Temporary storage for the character representation of the | |
2805 | * CPU bitmask (and one more byte for the newline): | |
2806 | */ | |
2807 | static char mask_str[NR_CPUS + 1]; | |
2808 | ||
c7078de1 IM |
2809 | static ssize_t |
2810 | tracing_cpumask_read(struct file *filp, char __user *ubuf, | |
2811 | size_t count, loff_t *ppos) | |
2812 | { | |
36dfe925 | 2813 | int len; |
c7078de1 IM |
2814 | |
2815 | mutex_lock(&tracing_cpumask_update_lock); | |
36dfe925 | 2816 | |
9e01c1b7 | 2817 | len = cpumask_scnprintf(mask_str, count, tracing_cpumask); |
36dfe925 IM |
2818 | if (count - len < 2) { |
2819 | count = -EINVAL; | |
2820 | goto out_err; | |
2821 | } | |
2822 | len += sprintf(mask_str + len, "\n"); | |
2823 | count = simple_read_from_buffer(ubuf, count, ppos, mask_str, NR_CPUS+1); | |
2824 | ||
2825 | out_err: | |
c7078de1 IM |
2826 | mutex_unlock(&tracing_cpumask_update_lock); |
2827 | ||
2828 | return count; | |
2829 | } | |
2830 | ||
2831 | static ssize_t | |
2832 | tracing_cpumask_write(struct file *filp, const char __user *ubuf, | |
2833 | size_t count, loff_t *ppos) | |
2834 | { | |
2b6080f2 | 2835 | struct trace_array *tr = filp->private_data; |
9e01c1b7 | 2836 | cpumask_var_t tracing_cpumask_new; |
2b6080f2 | 2837 | int err, cpu; |
9e01c1b7 RR |
2838 | |
2839 | if (!alloc_cpumask_var(&tracing_cpumask_new, GFP_KERNEL)) | |
2840 | return -ENOMEM; | |
c7078de1 | 2841 | |
9e01c1b7 | 2842 | err = cpumask_parse_user(ubuf, count, tracing_cpumask_new); |
c7078de1 | 2843 | if (err) |
36dfe925 IM |
2844 | goto err_unlock; |
2845 | ||
215368e8 LZ |
2846 | mutex_lock(&tracing_cpumask_update_lock); |
2847 | ||
a5e25883 | 2848 | local_irq_disable(); |
0199c4e6 | 2849 | arch_spin_lock(&ftrace_max_lock); |
ab46428c | 2850 | for_each_tracing_cpu(cpu) { |
36dfe925 IM |
2851 | /* |
2852 | * Increase/decrease the disabled counter if we are | |
2853 | * about to flip a bit in the cpumask: | |
2854 | */ | |
9e01c1b7 RR |
2855 | if (cpumask_test_cpu(cpu, tracing_cpumask) && |
2856 | !cpumask_test_cpu(cpu, tracing_cpumask_new)) { | |
a7603ff4 | 2857 | atomic_inc(&per_cpu_ptr(tr->data, cpu)->disabled); |
2b6080f2 | 2858 | ring_buffer_record_disable_cpu(tr->buffer, cpu); |
36dfe925 | 2859 | } |
9e01c1b7 RR |
2860 | if (!cpumask_test_cpu(cpu, tracing_cpumask) && |
2861 | cpumask_test_cpu(cpu, tracing_cpumask_new)) { | |
a7603ff4 | 2862 | atomic_dec(&per_cpu_ptr(tr->data, cpu)->disabled); |
2b6080f2 | 2863 | ring_buffer_record_enable_cpu(tr->buffer, cpu); |
36dfe925 IM |
2864 | } |
2865 | } | |
0199c4e6 | 2866 | arch_spin_unlock(&ftrace_max_lock); |
a5e25883 | 2867 | local_irq_enable(); |
36dfe925 | 2868 | |
9e01c1b7 | 2869 | cpumask_copy(tracing_cpumask, tracing_cpumask_new); |
36dfe925 IM |
2870 | |
2871 | mutex_unlock(&tracing_cpumask_update_lock); | |
9e01c1b7 | 2872 | free_cpumask_var(tracing_cpumask_new); |
c7078de1 IM |
2873 | |
2874 | return count; | |
36dfe925 IM |
2875 | |
2876 | err_unlock: | |
215368e8 | 2877 | free_cpumask_var(tracing_cpumask_new); |
36dfe925 IM |
2878 | |
2879 | return err; | |
c7078de1 IM |
2880 | } |
2881 | ||
5e2336a0 | 2882 | static const struct file_operations tracing_cpumask_fops = { |
c7078de1 IM |
2883 | .open = tracing_open_generic, |
2884 | .read = tracing_cpumask_read, | |
2885 | .write = tracing_cpumask_write, | |
b444786f | 2886 | .llseek = generic_file_llseek, |
bc0c38d1 SR |
2887 | }; |
2888 | ||
fdb372ed | 2889 | static int tracing_trace_options_show(struct seq_file *m, void *v) |
bc0c38d1 | 2890 | { |
d8e83d26 | 2891 | struct tracer_opt *trace_opts; |
2b6080f2 | 2892 | struct trace_array *tr = m->private; |
d8e83d26 | 2893 | u32 tracer_flags; |
d8e83d26 | 2894 | int i; |
adf9f195 | 2895 | |
d8e83d26 | 2896 | mutex_lock(&trace_types_lock); |
2b6080f2 SR |
2897 | tracer_flags = tr->current_trace->flags->val; |
2898 | trace_opts = tr->current_trace->flags->opts; | |
d8e83d26 | 2899 | |
bc0c38d1 SR |
2900 | for (i = 0; trace_options[i]; i++) { |
2901 | if (trace_flags & (1 << i)) | |
fdb372ed | 2902 | seq_printf(m, "%s\n", trace_options[i]); |
bc0c38d1 | 2903 | else |
fdb372ed | 2904 | seq_printf(m, "no%s\n", trace_options[i]); |
bc0c38d1 SR |
2905 | } |
2906 | ||
adf9f195 FW |
2907 | for (i = 0; trace_opts[i].name; i++) { |
2908 | if (tracer_flags & trace_opts[i].bit) | |
fdb372ed | 2909 | seq_printf(m, "%s\n", trace_opts[i].name); |
adf9f195 | 2910 | else |
fdb372ed | 2911 | seq_printf(m, "no%s\n", trace_opts[i].name); |
adf9f195 | 2912 | } |
d8e83d26 | 2913 | mutex_unlock(&trace_types_lock); |
adf9f195 | 2914 | |
fdb372ed | 2915 | return 0; |
bc0c38d1 | 2916 | } |
bc0c38d1 | 2917 | |
8d18eaaf LZ |
2918 | static int __set_tracer_option(struct tracer *trace, |
2919 | struct tracer_flags *tracer_flags, | |
2920 | struct tracer_opt *opts, int neg) | |
2921 | { | |
2922 | int ret; | |
bc0c38d1 | 2923 | |
8d18eaaf LZ |
2924 | ret = trace->set_flag(tracer_flags->val, opts->bit, !neg); |
2925 | if (ret) | |
2926 | return ret; | |
2927 | ||
2928 | if (neg) | |
2929 | tracer_flags->val &= ~opts->bit; | |
2930 | else | |
2931 | tracer_flags->val |= opts->bit; | |
2932 | return 0; | |
bc0c38d1 SR |
2933 | } |
2934 | ||
adf9f195 FW |
2935 | /* Try to assign a tracer specific option */ |
2936 | static int set_tracer_option(struct tracer *trace, char *cmp, int neg) | |
2937 | { | |
7770841e | 2938 | struct tracer_flags *tracer_flags = trace->flags; |
adf9f195 | 2939 | struct tracer_opt *opts = NULL; |
8d18eaaf | 2940 | int i; |
adf9f195 | 2941 | |
7770841e Z |
2942 | for (i = 0; tracer_flags->opts[i].name; i++) { |
2943 | opts = &tracer_flags->opts[i]; | |
adf9f195 | 2944 | |
8d18eaaf LZ |
2945 | if (strcmp(cmp, opts->name) == 0) |
2946 | return __set_tracer_option(trace, trace->flags, | |
2947 | opts, neg); | |
adf9f195 | 2948 | } |
adf9f195 | 2949 | |
8d18eaaf | 2950 | return -EINVAL; |
adf9f195 FW |
2951 | } |
2952 | ||
613f04a0 SRRH |
2953 | /* Some tracers require overwrite to stay enabled */ |
2954 | int trace_keep_overwrite(struct tracer *tracer, u32 mask, int set) | |
2955 | { | |
2956 | if (tracer->enabled && (mask & TRACE_ITER_OVERWRITE) && !set) | |
2957 | return -1; | |
2958 | ||
2959 | return 0; | |
2960 | } | |
2961 | ||
2b6080f2 | 2962 | int set_tracer_flag(struct trace_array *tr, unsigned int mask, int enabled) |
af4617bd SR |
2963 | { |
2964 | /* do nothing if flag is already set */ | |
2965 | if (!!(trace_flags & mask) == !!enabled) | |
613f04a0 SRRH |
2966 | return 0; |
2967 | ||
2968 | /* Give the tracer a chance to approve the change */ | |
2b6080f2 SR |
2969 | if (tr->current_trace->flag_changed) |
2970 | if (tr->current_trace->flag_changed(tr->current_trace, mask, !!enabled)) | |
613f04a0 | 2971 | return -EINVAL; |
af4617bd SR |
2972 | |
2973 | if (enabled) | |
2974 | trace_flags |= mask; | |
2975 | else | |
2976 | trace_flags &= ~mask; | |
e870e9a1 LZ |
2977 | |
2978 | if (mask == TRACE_ITER_RECORD_CMD) | |
2979 | trace_event_enable_cmd_record(enabled); | |
750912fa | 2980 | |
80902822 | 2981 | if (mask == TRACE_ITER_OVERWRITE) { |
750912fa | 2982 | ring_buffer_change_overwrite(global_trace.buffer, enabled); |
80902822 SRRH |
2983 | #ifdef CONFIG_TRACER_MAX_TRACE |
2984 | ring_buffer_change_overwrite(max_tr.buffer, enabled); | |
2985 | #endif | |
2986 | } | |
81698831 SR |
2987 | |
2988 | if (mask == TRACE_ITER_PRINTK) | |
2989 | trace_printk_start_stop_comm(enabled); | |
613f04a0 SRRH |
2990 | |
2991 | return 0; | |
af4617bd SR |
2992 | } |
2993 | ||
2b6080f2 | 2994 | static int trace_set_options(struct trace_array *tr, char *option) |
bc0c38d1 | 2995 | { |
8d18eaaf | 2996 | char *cmp; |
bc0c38d1 | 2997 | int neg = 0; |
613f04a0 | 2998 | int ret = -ENODEV; |
bc0c38d1 SR |
2999 | int i; |
3000 | ||
7bcfaf54 | 3001 | cmp = strstrip(option); |
bc0c38d1 | 3002 | |
8d18eaaf | 3003 | if (strncmp(cmp, "no", 2) == 0) { |
bc0c38d1 SR |
3004 | neg = 1; |
3005 | cmp += 2; | |
3006 | } | |
3007 | ||
69d34da2 SRRH |
3008 | mutex_lock(&trace_types_lock); |
3009 | ||
bc0c38d1 | 3010 | for (i = 0; trace_options[i]; i++) { |
8d18eaaf | 3011 | if (strcmp(cmp, trace_options[i]) == 0) { |
2b6080f2 | 3012 | ret = set_tracer_flag(tr, 1 << i, !neg); |
bc0c38d1 SR |
3013 | break; |
3014 | } | |
3015 | } | |
adf9f195 FW |
3016 | |
3017 | /* If no option could be set, test the specific tracer options */ | |
69d34da2 | 3018 | if (!trace_options[i]) |
2b6080f2 | 3019 | ret = set_tracer_option(tr->current_trace, cmp, neg); |
69d34da2 SRRH |
3020 | |
3021 | mutex_unlock(&trace_types_lock); | |
bc0c38d1 | 3022 | |
7bcfaf54 SR |
3023 | return ret; |
3024 | } | |
3025 | ||
3026 | static ssize_t | |
3027 | tracing_trace_options_write(struct file *filp, const char __user *ubuf, | |
3028 | size_t cnt, loff_t *ppos) | |
3029 | { | |
2b6080f2 SR |
3030 | struct seq_file *m = filp->private_data; |
3031 | struct trace_array *tr = m->private; | |
7bcfaf54 | 3032 | char buf[64]; |
613f04a0 | 3033 | int ret; |
7bcfaf54 SR |
3034 | |
3035 | if (cnt >= sizeof(buf)) | |
3036 | return -EINVAL; | |
3037 | ||
3038 | if (copy_from_user(&buf, ubuf, cnt)) | |
3039 | return -EFAULT; | |
3040 | ||
a8dd2176 SR |
3041 | buf[cnt] = 0; |
3042 | ||
2b6080f2 | 3043 | ret = trace_set_options(tr, buf); |
613f04a0 SRRH |
3044 | if (ret < 0) |
3045 | return ret; | |
7bcfaf54 | 3046 | |
cf8517cf | 3047 | *ppos += cnt; |
bc0c38d1 SR |
3048 | |
3049 | return cnt; | |
3050 | } | |
3051 | ||
fdb372ed LZ |
3052 | static int tracing_trace_options_open(struct inode *inode, struct file *file) |
3053 | { | |
3054 | if (tracing_disabled) | |
3055 | return -ENODEV; | |
2b6080f2 SR |
3056 | |
3057 | return single_open(file, tracing_trace_options_show, inode->i_private); | |
fdb372ed LZ |
3058 | } |
3059 | ||
5e2336a0 | 3060 | static const struct file_operations tracing_iter_fops = { |
fdb372ed LZ |
3061 | .open = tracing_trace_options_open, |
3062 | .read = seq_read, | |
3063 | .llseek = seq_lseek, | |
3064 | .release = single_release, | |
ee6bce52 | 3065 | .write = tracing_trace_options_write, |
bc0c38d1 SR |
3066 | }; |
3067 | ||
7bd2f24c IM |
3068 | static const char readme_msg[] = |
3069 | "tracing mini-HOWTO:\n\n" | |
156f5a78 GL |
3070 | "# mount -t debugfs nodev /sys/kernel/debug\n\n" |
3071 | "# cat /sys/kernel/debug/tracing/available_tracers\n" | |
1e42e83f | 3072 | "wakeup wakeup_rt preemptirqsoff preemptoff irqsoff function nop\n\n" |
156f5a78 | 3073 | "# cat /sys/kernel/debug/tracing/current_tracer\n" |
bc2b6871 | 3074 | "nop\n" |
1e42e83f | 3075 | "# echo wakeup > /sys/kernel/debug/tracing/current_tracer\n" |
156f5a78 | 3076 | "# cat /sys/kernel/debug/tracing/current_tracer\n" |
1e42e83f | 3077 | "wakeup\n" |
156f5a78 | 3078 | "# cat /sys/kernel/debug/tracing/trace_options\n" |
7bd2f24c | 3079 | "noprint-parent nosym-offset nosym-addr noverbose\n" |
156f5a78 | 3080 | "# echo print-parent > /sys/kernel/debug/tracing/trace_options\n" |
9b5f8b31 | 3081 | "# echo 1 > /sys/kernel/debug/tracing/tracing_on\n" |
156f5a78 | 3082 | "# cat /sys/kernel/debug/tracing/trace > /tmp/trace.txt\n" |
9b5f8b31 | 3083 | "# echo 0 > /sys/kernel/debug/tracing/tracing_on\n" |
7bd2f24c IM |
3084 | ; |
3085 | ||
3086 | static ssize_t | |
3087 | tracing_readme_read(struct file *filp, char __user *ubuf, | |
3088 | size_t cnt, loff_t *ppos) | |
3089 | { | |
3090 | return simple_read_from_buffer(ubuf, cnt, ppos, | |
3091 | readme_msg, strlen(readme_msg)); | |
3092 | } | |
3093 | ||
5e2336a0 | 3094 | static const struct file_operations tracing_readme_fops = { |
c7078de1 IM |
3095 | .open = tracing_open_generic, |
3096 | .read = tracing_readme_read, | |
b444786f | 3097 | .llseek = generic_file_llseek, |
7bd2f24c IM |
3098 | }; |
3099 | ||
69abe6a5 AP |
3100 | static ssize_t |
3101 | tracing_saved_cmdlines_read(struct file *file, char __user *ubuf, | |
3102 | size_t cnt, loff_t *ppos) | |
3103 | { | |
3104 | char *buf_comm; | |
3105 | char *file_buf; | |
3106 | char *buf; | |
3107 | int len = 0; | |
3108 | int pid; | |
3109 | int i; | |
3110 | ||
3111 | file_buf = kmalloc(SAVED_CMDLINES*(16+TASK_COMM_LEN), GFP_KERNEL); | |
3112 | if (!file_buf) | |
3113 | return -ENOMEM; | |
3114 | ||
3115 | buf_comm = kmalloc(TASK_COMM_LEN, GFP_KERNEL); | |
3116 | if (!buf_comm) { | |
3117 | kfree(file_buf); | |
3118 | return -ENOMEM; | |
3119 | } | |
3120 | ||
3121 | buf = file_buf; | |
3122 | ||
3123 | for (i = 0; i < SAVED_CMDLINES; i++) { | |
3124 | int r; | |
3125 | ||
3126 | pid = map_cmdline_to_pid[i]; | |
3127 | if (pid == -1 || pid == NO_CMDLINE_MAP) | |
3128 | continue; | |
3129 | ||
3130 | trace_find_cmdline(pid, buf_comm); | |
3131 | r = sprintf(buf, "%d %s\n", pid, buf_comm); | |
3132 | buf += r; | |
3133 | len += r; | |
3134 | } | |
3135 | ||
3136 | len = simple_read_from_buffer(ubuf, cnt, ppos, | |
3137 | file_buf, len); | |
3138 | ||
3139 | kfree(file_buf); | |
3140 | kfree(buf_comm); | |
3141 | ||
3142 | return len; | |
3143 | } | |
3144 | ||
3145 | static const struct file_operations tracing_saved_cmdlines_fops = { | |
3146 | .open = tracing_open_generic, | |
3147 | .read = tracing_saved_cmdlines_read, | |
b444786f | 3148 | .llseek = generic_file_llseek, |
69abe6a5 AP |
3149 | }; |
3150 | ||
bc0c38d1 SR |
3151 | static ssize_t |
3152 | tracing_set_trace_read(struct file *filp, char __user *ubuf, | |
3153 | size_t cnt, loff_t *ppos) | |
3154 | { | |
2b6080f2 | 3155 | struct trace_array *tr = filp->private_data; |
ee6c2c1b | 3156 | char buf[MAX_TRACER_SIZE+2]; |
bc0c38d1 SR |
3157 | int r; |
3158 | ||
3159 | mutex_lock(&trace_types_lock); | |
2b6080f2 | 3160 | r = sprintf(buf, "%s\n", tr->current_trace->name); |
bc0c38d1 SR |
3161 | mutex_unlock(&trace_types_lock); |
3162 | ||
4bf39a94 | 3163 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, r); |
bc0c38d1 SR |
3164 | } |
3165 | ||
b6f11df2 ACM |
3166 | int tracer_init(struct tracer *t, struct trace_array *tr) |
3167 | { | |
3168 | tracing_reset_online_cpus(tr); | |
3169 | return t->init(tr); | |
3170 | } | |
3171 | ||
438ced17 VN |
3172 | static void set_buffer_entries(struct trace_array *tr, unsigned long val) |
3173 | { | |
3174 | int cpu; | |
3175 | for_each_tracing_cpu(cpu) | |
a7603ff4 | 3176 | per_cpu_ptr(tr->data, cpu)->entries = val; |
438ced17 VN |
3177 | } |
3178 | ||
d60da506 HT |
3179 | /* resize @tr's buffer to the size of @size_tr's entries */ |
3180 | static int resize_buffer_duplicate_size(struct trace_array *tr, | |
3181 | struct trace_array *size_tr, int cpu_id) | |
3182 | { | |
3183 | int cpu, ret = 0; | |
3184 | ||
3185 | if (cpu_id == RING_BUFFER_ALL_CPUS) { | |
3186 | for_each_tracing_cpu(cpu) { | |
3187 | ret = ring_buffer_resize(tr->buffer, | |
a7603ff4 | 3188 | per_cpu_ptr(size_tr->data, cpu)->entries, cpu); |
d60da506 HT |
3189 | if (ret < 0) |
3190 | break; | |
a7603ff4 SR |
3191 | per_cpu_ptr(tr->data, cpu)->entries = |
3192 | per_cpu_ptr(size_tr->data, cpu)->entries; | |
d60da506 HT |
3193 | } |
3194 | } else { | |
3195 | ret = ring_buffer_resize(tr->buffer, | |
a7603ff4 | 3196 | per_cpu_ptr(size_tr->data, cpu_id)->entries, cpu_id); |
d60da506 | 3197 | if (ret == 0) |
a7603ff4 SR |
3198 | per_cpu_ptr(tr->data, cpu_id)->entries = |
3199 | per_cpu_ptr(size_tr->data, cpu_id)->entries; | |
d60da506 HT |
3200 | } |
3201 | ||
3202 | return ret; | |
3203 | } | |
3204 | ||
2b6080f2 SR |
3205 | static int __tracing_resize_ring_buffer(struct trace_array *tr, |
3206 | unsigned long size, int cpu) | |
73c5162a SR |
3207 | { |
3208 | int ret; | |
3209 | ||
3210 | /* | |
3211 | * If kernel or user changes the size of the ring buffer | |
a123c52b SR |
3212 | * we use the size that was given, and we can forget about |
3213 | * expanding it later. | |
73c5162a SR |
3214 | */ |
3215 | ring_buffer_expanded = 1; | |
3216 | ||
b382ede6 | 3217 | /* May be called before buffers are initialized */ |
2b6080f2 | 3218 | if (!tr->buffer) |
b382ede6 SR |
3219 | return 0; |
3220 | ||
2b6080f2 | 3221 | ret = ring_buffer_resize(tr->buffer, size, cpu); |
73c5162a SR |
3222 | if (ret < 0) |
3223 | return ret; | |
3224 | ||
2b6080f2 SR |
3225 | if (!(tr->flags & TRACE_ARRAY_FL_GLOBAL) || |
3226 | !tr->current_trace->use_max_tr) | |
ef710e10 KM |
3227 | goto out; |
3228 | ||
438ced17 | 3229 | ret = ring_buffer_resize(max_tr.buffer, size, cpu); |
73c5162a | 3230 | if (ret < 0) { |
2b6080f2 | 3231 | int r = resize_buffer_duplicate_size(tr, tr, cpu); |
73c5162a | 3232 | if (r < 0) { |
a123c52b SR |
3233 | /* |
3234 | * AARGH! We are left with different | |
3235 | * size max buffer!!!! | |
3236 | * The max buffer is our "snapshot" buffer. | |
3237 | * When a tracer needs a snapshot (one of the | |
3238 | * latency tracers), it swaps the max buffer | |
3239 | * with the saved snap shot. We succeeded to | |
3240 | * update the size of the main buffer, but failed to | |
3241 | * update the size of the max buffer. But when we tried | |
3242 | * to reset the main buffer to the original size, we | |
3243 | * failed there too. This is very unlikely to | |
3244 | * happen, but if it does, warn and kill all | |
3245 | * tracing. | |
3246 | */ | |
73c5162a SR |
3247 | WARN_ON(1); |
3248 | tracing_disabled = 1; | |
3249 | } | |
3250 | return ret; | |
3251 | } | |
3252 | ||
438ced17 VN |
3253 | if (cpu == RING_BUFFER_ALL_CPUS) |
3254 | set_buffer_entries(&max_tr, size); | |
3255 | else | |
a7603ff4 | 3256 | per_cpu_ptr(max_tr.data, cpu)->entries = size; |
438ced17 | 3257 | |
ef710e10 | 3258 | out: |
438ced17 | 3259 | if (cpu == RING_BUFFER_ALL_CPUS) |
2b6080f2 | 3260 | set_buffer_entries(tr, size); |
438ced17 | 3261 | else |
a7603ff4 | 3262 | per_cpu_ptr(tr->data, cpu)->entries = size; |
73c5162a SR |
3263 | |
3264 | return ret; | |
3265 | } | |
3266 | ||
2b6080f2 SR |
3267 | static ssize_t tracing_resize_ring_buffer(struct trace_array *tr, |
3268 | unsigned long size, int cpu_id) | |
4f271a2a | 3269 | { |
83f40318 | 3270 | int ret = size; |
4f271a2a VN |
3271 | |
3272 | mutex_lock(&trace_types_lock); | |
3273 | ||
438ced17 VN |
3274 | if (cpu_id != RING_BUFFER_ALL_CPUS) { |
3275 | /* make sure, this cpu is enabled in the mask */ | |
3276 | if (!cpumask_test_cpu(cpu_id, tracing_buffer_mask)) { | |
3277 | ret = -EINVAL; | |
3278 | goto out; | |
3279 | } | |
3280 | } | |
4f271a2a | 3281 | |
2b6080f2 | 3282 | ret = __tracing_resize_ring_buffer(tr, size, cpu_id); |
4f271a2a VN |
3283 | if (ret < 0) |
3284 | ret = -ENOMEM; | |
3285 | ||
438ced17 | 3286 | out: |
4f271a2a VN |
3287 | mutex_unlock(&trace_types_lock); |
3288 | ||
3289 | return ret; | |
3290 | } | |
3291 | ||
ef710e10 | 3292 | |
1852fcce SR |
3293 | /** |
3294 | * tracing_update_buffers - used by tracing facility to expand ring buffers | |
3295 | * | |
3296 | * To save on memory when the tracing is never used on a system with it | |
3297 | * configured in. The ring buffers are set to a minimum size. But once | |
3298 | * a user starts to use the tracing facility, then they need to grow | |
3299 | * to their default size. | |
3300 | * | |
3301 | * This function is to be called when a tracer is about to be used. | |
3302 | */ | |
3303 | int tracing_update_buffers(void) | |
3304 | { | |
3305 | int ret = 0; | |
3306 | ||
1027fcb2 | 3307 | mutex_lock(&trace_types_lock); |
1852fcce | 3308 | if (!ring_buffer_expanded) |
2b6080f2 | 3309 | ret = __tracing_resize_ring_buffer(&global_trace, trace_buf_size, |
438ced17 | 3310 | RING_BUFFER_ALL_CPUS); |
1027fcb2 | 3311 | mutex_unlock(&trace_types_lock); |
1852fcce SR |
3312 | |
3313 | return ret; | |
3314 | } | |
3315 | ||
577b785f SR |
3316 | struct trace_option_dentry; |
3317 | ||
3318 | static struct trace_option_dentry * | |
2b6080f2 | 3319 | create_trace_option_files(struct trace_array *tr, struct tracer *tracer); |
577b785f SR |
3320 | |
3321 | static void | |
3322 | destroy_trace_option_files(struct trace_option_dentry *topts); | |
3323 | ||
b2821ae6 | 3324 | static int tracing_set_tracer(const char *buf) |
bc0c38d1 | 3325 | { |
577b785f | 3326 | static struct trace_option_dentry *topts; |
bc0c38d1 SR |
3327 | struct trace_array *tr = &global_trace; |
3328 | struct tracer *t; | |
34600f0e | 3329 | bool had_max_tr; |
d9e54076 | 3330 | int ret = 0; |
bc0c38d1 | 3331 | |
1027fcb2 SR |
3332 | mutex_lock(&trace_types_lock); |
3333 | ||
73c5162a | 3334 | if (!ring_buffer_expanded) { |
2b6080f2 | 3335 | ret = __tracing_resize_ring_buffer(tr, trace_buf_size, |
438ced17 | 3336 | RING_BUFFER_ALL_CPUS); |
73c5162a | 3337 | if (ret < 0) |
59f586db | 3338 | goto out; |
73c5162a SR |
3339 | ret = 0; |
3340 | } | |
3341 | ||
bc0c38d1 SR |
3342 | for (t = trace_types; t; t = t->next) { |
3343 | if (strcmp(t->name, buf) == 0) | |
3344 | break; | |
3345 | } | |
c2931e05 FW |
3346 | if (!t) { |
3347 | ret = -EINVAL; | |
3348 | goto out; | |
3349 | } | |
2b6080f2 | 3350 | if (t == tr->current_trace) |
bc0c38d1 SR |
3351 | goto out; |
3352 | ||
9f029e83 | 3353 | trace_branch_disable(); |
613f04a0 | 3354 | |
2b6080f2 | 3355 | tr->current_trace->enabled = false; |
613f04a0 | 3356 | |
2b6080f2 SR |
3357 | if (tr->current_trace->reset) |
3358 | tr->current_trace->reset(tr); | |
34600f0e | 3359 | |
2b6080f2 SR |
3360 | had_max_tr = tr->current_trace->allocated_snapshot; |
3361 | tr->current_trace = &nop_trace; | |
34600f0e SR |
3362 | |
3363 | if (had_max_tr && !t->use_max_tr) { | |
3364 | /* | |
3365 | * We need to make sure that the update_max_tr sees that | |
3366 | * current_trace changed to nop_trace to keep it from | |
3367 | * swapping the buffers after we resize it. | |
3368 | * The update_max_tr is called from interrupts disabled | |
3369 | * so a synchronized_sched() is sufficient. | |
3370 | */ | |
3371 | synchronize_sched(); | |
ef710e10 KM |
3372 | /* |
3373 | * We don't free the ring buffer. instead, resize it because | |
3374 | * The max_tr ring buffer has some state (e.g. ring->clock) and | |
3375 | * we want preserve it. | |
3376 | */ | |
438ced17 VN |
3377 | ring_buffer_resize(max_tr.buffer, 1, RING_BUFFER_ALL_CPUS); |
3378 | set_buffer_entries(&max_tr, 1); | |
debdd57f | 3379 | tracing_reset_online_cpus(&max_tr); |
2b6080f2 | 3380 | tr->current_trace->allocated_snapshot = false; |
ef710e10 | 3381 | } |
577b785f SR |
3382 | destroy_trace_option_files(topts); |
3383 | ||
2b6080f2 | 3384 | topts = create_trace_option_files(tr, t); |
34600f0e | 3385 | if (t->use_max_tr && !had_max_tr) { |
438ced17 | 3386 | /* we need to make per cpu buffer sizes equivalent */ |
d60da506 HT |
3387 | ret = resize_buffer_duplicate_size(&max_tr, &global_trace, |
3388 | RING_BUFFER_ALL_CPUS); | |
3389 | if (ret < 0) | |
3390 | goto out; | |
debdd57f | 3391 | t->allocated_snapshot = true; |
ef710e10 | 3392 | } |
577b785f | 3393 | |
1c80025a | 3394 | if (t->init) { |
b6f11df2 | 3395 | ret = tracer_init(t, tr); |
1c80025a FW |
3396 | if (ret) |
3397 | goto out; | |
3398 | } | |
bc0c38d1 | 3399 | |
2b6080f2 SR |
3400 | tr->current_trace = t; |
3401 | tr->current_trace->enabled = true; | |
9f029e83 | 3402 | trace_branch_enable(tr); |
bc0c38d1 SR |
3403 | out: |
3404 | mutex_unlock(&trace_types_lock); | |
3405 | ||
d9e54076 PZ |
3406 | return ret; |
3407 | } | |
3408 | ||
3409 | static ssize_t | |
3410 | tracing_set_trace_write(struct file *filp, const char __user *ubuf, | |
3411 | size_t cnt, loff_t *ppos) | |
3412 | { | |
ee6c2c1b | 3413 | char buf[MAX_TRACER_SIZE+1]; |
d9e54076 PZ |
3414 | int i; |
3415 | size_t ret; | |
e6e7a65a FW |
3416 | int err; |
3417 | ||
3418 | ret = cnt; | |
d9e54076 | 3419 | |
ee6c2c1b LZ |
3420 | if (cnt > MAX_TRACER_SIZE) |
3421 | cnt = MAX_TRACER_SIZE; | |
d9e54076 PZ |
3422 | |
3423 | if (copy_from_user(&buf, ubuf, cnt)) | |
3424 | return -EFAULT; | |
3425 | ||
3426 | buf[cnt] = 0; | |
3427 | ||
3428 | /* strip ending whitespace. */ | |
3429 | for (i = cnt - 1; i > 0 && isspace(buf[i]); i--) | |
3430 | buf[i] = 0; | |
3431 | ||
e6e7a65a FW |
3432 | err = tracing_set_tracer(buf); |
3433 | if (err) | |
3434 | return err; | |
d9e54076 | 3435 | |
cf8517cf | 3436 | *ppos += ret; |
bc0c38d1 | 3437 | |
c2931e05 | 3438 | return ret; |
bc0c38d1 SR |
3439 | } |
3440 | ||
3441 | static ssize_t | |
3442 | tracing_max_lat_read(struct file *filp, char __user *ubuf, | |
3443 | size_t cnt, loff_t *ppos) | |
3444 | { | |
3445 | unsigned long *ptr = filp->private_data; | |
3446 | char buf[64]; | |
3447 | int r; | |
3448 | ||
cffae437 | 3449 | r = snprintf(buf, sizeof(buf), "%ld\n", |
bc0c38d1 | 3450 | *ptr == (unsigned long)-1 ? -1 : nsecs_to_usecs(*ptr)); |
cffae437 SR |
3451 | if (r > sizeof(buf)) |
3452 | r = sizeof(buf); | |
4bf39a94 | 3453 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, r); |
bc0c38d1 SR |
3454 | } |
3455 | ||
3456 | static ssize_t | |
3457 | tracing_max_lat_write(struct file *filp, const char __user *ubuf, | |
3458 | size_t cnt, loff_t *ppos) | |
3459 | { | |
5e39841c | 3460 | unsigned long *ptr = filp->private_data; |
5e39841c | 3461 | unsigned long val; |
c6caeeb1 | 3462 | int ret; |
bc0c38d1 | 3463 | |
22fe9b54 PH |
3464 | ret = kstrtoul_from_user(ubuf, cnt, 10, &val); |
3465 | if (ret) | |
c6caeeb1 | 3466 | return ret; |
bc0c38d1 SR |
3467 | |
3468 | *ptr = val * 1000; | |
3469 | ||
3470 | return cnt; | |
3471 | } | |
3472 | ||
b3806b43 SR |
3473 | static int tracing_open_pipe(struct inode *inode, struct file *filp) |
3474 | { | |
2b6080f2 SR |
3475 | struct trace_cpu *tc = inode->i_private; |
3476 | struct trace_array *tr = tc->tr; | |
b3806b43 | 3477 | struct trace_iterator *iter; |
b04cc6b1 | 3478 | int ret = 0; |
b3806b43 SR |
3479 | |
3480 | if (tracing_disabled) | |
3481 | return -ENODEV; | |
3482 | ||
b04cc6b1 FW |
3483 | mutex_lock(&trace_types_lock); |
3484 | ||
b3806b43 SR |
3485 | /* create a buffer to store the information to pass to userspace */ |
3486 | iter = kzalloc(sizeof(*iter), GFP_KERNEL); | |
b04cc6b1 FW |
3487 | if (!iter) { |
3488 | ret = -ENOMEM; | |
3489 | goto out; | |
3490 | } | |
b3806b43 | 3491 | |
d7350c3f FW |
3492 | /* |
3493 | * We make a copy of the current tracer to avoid concurrent | |
3494 | * changes on it while we are reading. | |
3495 | */ | |
3496 | iter->trace = kmalloc(sizeof(*iter->trace), GFP_KERNEL); | |
3497 | if (!iter->trace) { | |
3498 | ret = -ENOMEM; | |
3499 | goto fail; | |
3500 | } | |
2b6080f2 | 3501 | *iter->trace = *tr->current_trace; |
d7350c3f | 3502 | |
4462344e | 3503 | if (!alloc_cpumask_var(&iter->started, GFP_KERNEL)) { |
b04cc6b1 | 3504 | ret = -ENOMEM; |
d7350c3f | 3505 | goto fail; |
4462344e RR |
3506 | } |
3507 | ||
a309720c | 3508 | /* trace pipe does not show start of buffer */ |
4462344e | 3509 | cpumask_setall(iter->started); |
a309720c | 3510 | |
112f38a7 SR |
3511 | if (trace_flags & TRACE_ITER_LATENCY_FMT) |
3512 | iter->iter_flags |= TRACE_FILE_LAT_FMT; | |
3513 | ||
8be0709f DS |
3514 | /* Output in nanoseconds only if we are using a clock in nanoseconds. */ |
3515 | if (trace_clocks[trace_clock_id].in_ns) | |
3516 | iter->iter_flags |= TRACE_FILE_TIME_IN_NS; | |
3517 | ||
2b6080f2 SR |
3518 | iter->cpu_file = tc->cpu; |
3519 | iter->tr = tc->tr; | |
d7350c3f | 3520 | mutex_init(&iter->mutex); |
b3806b43 SR |
3521 | filp->private_data = iter; |
3522 | ||
107bad8b SR |
3523 | if (iter->trace->pipe_open) |
3524 | iter->trace->pipe_open(iter); | |
107bad8b | 3525 | |
b444786f | 3526 | nonseekable_open(inode, filp); |
b04cc6b1 FW |
3527 | out: |
3528 | mutex_unlock(&trace_types_lock); | |
3529 | return ret; | |
d7350c3f FW |
3530 | |
3531 | fail: | |
3532 | kfree(iter->trace); | |
3533 | kfree(iter); | |
3534 | mutex_unlock(&trace_types_lock); | |
3535 | return ret; | |
b3806b43 SR |
3536 | } |
3537 | ||
3538 | static int tracing_release_pipe(struct inode *inode, struct file *file) | |
3539 | { | |
3540 | struct trace_iterator *iter = file->private_data; | |
3541 | ||
b04cc6b1 FW |
3542 | mutex_lock(&trace_types_lock); |
3543 | ||
29bf4a5e | 3544 | if (iter->trace->pipe_close) |
c521efd1 SR |
3545 | iter->trace->pipe_close(iter); |
3546 | ||
b04cc6b1 FW |
3547 | mutex_unlock(&trace_types_lock); |
3548 | ||
4462344e | 3549 | free_cpumask_var(iter->started); |
d7350c3f FW |
3550 | mutex_destroy(&iter->mutex); |
3551 | kfree(iter->trace); | |
b3806b43 | 3552 | kfree(iter); |
b3806b43 SR |
3553 | |
3554 | return 0; | |
3555 | } | |
3556 | ||
2a2cc8f7 SSP |
3557 | static unsigned int |
3558 | tracing_poll_pipe(struct file *filp, poll_table *poll_table) | |
3559 | { | |
3560 | struct trace_iterator *iter = filp->private_data; | |
3561 | ||
3562 | if (trace_flags & TRACE_ITER_BLOCK) { | |
3563 | /* | |
3564 | * Always select as readable when in blocking mode | |
3565 | */ | |
3566 | return POLLIN | POLLRDNORM; | |
afc2abc0 | 3567 | } else { |
2a2cc8f7 SSP |
3568 | if (!trace_empty(iter)) |
3569 | return POLLIN | POLLRDNORM; | |
3570 | poll_wait(filp, &trace_wait, poll_table); | |
3571 | if (!trace_empty(iter)) | |
3572 | return POLLIN | POLLRDNORM; | |
3573 | ||
3574 | return 0; | |
3575 | } | |
3576 | } | |
3577 | ||
6eaaa5d5 FW |
3578 | /* |
3579 | * This is a make-shift waitqueue. | |
3580 | * A tracer might use this callback on some rare cases: | |
3581 | * | |
3582 | * 1) the current tracer might hold the runqueue lock when it wakes up | |
3583 | * a reader, hence a deadlock (sched, function, and function graph tracers) | |
3584 | * 2) the function tracers, trace all functions, we don't want | |
3585 | * the overhead of calling wake_up and friends | |
3586 | * (and tracing them too) | |
3587 | * | |
3588 | * Anyway, this is really very primitive wakeup. | |
3589 | */ | |
3590 | void poll_wait_pipe(struct trace_iterator *iter) | |
3591 | { | |
3592 | set_current_state(TASK_INTERRUPTIBLE); | |
3593 | /* sleep for 100 msecs, and try again. */ | |
3594 | schedule_timeout(HZ / 10); | |
3595 | } | |
3596 | ||
ff98781b EGM |
3597 | /* Must be called with trace_types_lock mutex held. */ |
3598 | static int tracing_wait_pipe(struct file *filp) | |
b3806b43 SR |
3599 | { |
3600 | struct trace_iterator *iter = filp->private_data; | |
b3806b43 | 3601 | |
b3806b43 | 3602 | while (trace_empty(iter)) { |
2dc8f095 | 3603 | |
107bad8b | 3604 | if ((filp->f_flags & O_NONBLOCK)) { |
ff98781b | 3605 | return -EAGAIN; |
107bad8b | 3606 | } |
2dc8f095 | 3607 | |
d7350c3f | 3608 | mutex_unlock(&iter->mutex); |
107bad8b | 3609 | |
6eaaa5d5 | 3610 | iter->trace->wait_pipe(iter); |
b3806b43 | 3611 | |
d7350c3f | 3612 | mutex_lock(&iter->mutex); |
107bad8b | 3613 | |
6eaaa5d5 | 3614 | if (signal_pending(current)) |
ff98781b | 3615 | return -EINTR; |
b3806b43 SR |
3616 | |
3617 | /* | |
250bfd3d | 3618 | * We block until we read something and tracing is disabled. |
b3806b43 SR |
3619 | * We still block if tracing is disabled, but we have never |
3620 | * read anything. This allows a user to cat this file, and | |
3621 | * then enable tracing. But after we have read something, | |
3622 | * we give an EOF when tracing is again disabled. | |
3623 | * | |
3624 | * iter->pos will be 0 if we haven't read anything. | |
3625 | */ | |
250bfd3d | 3626 | if (!tracing_is_enabled() && iter->pos) |
b3806b43 | 3627 | break; |
b3806b43 SR |
3628 | } |
3629 | ||
ff98781b EGM |
3630 | return 1; |
3631 | } | |
3632 | ||
3633 | /* | |
3634 | * Consumer reader. | |
3635 | */ | |
3636 | static ssize_t | |
3637 | tracing_read_pipe(struct file *filp, char __user *ubuf, | |
3638 | size_t cnt, loff_t *ppos) | |
3639 | { | |
3640 | struct trace_iterator *iter = filp->private_data; | |
2b6080f2 | 3641 | struct trace_array *tr = iter->tr; |
ff98781b EGM |
3642 | ssize_t sret; |
3643 | ||
3644 | /* return any leftover data */ | |
3645 | sret = trace_seq_to_user(&iter->seq, ubuf, cnt); | |
3646 | if (sret != -EBUSY) | |
3647 | return sret; | |
3648 | ||
f9520750 | 3649 | trace_seq_init(&iter->seq); |
ff98781b | 3650 | |
d7350c3f | 3651 | /* copy the tracer to avoid using a global lock all around */ |
ff98781b | 3652 | mutex_lock(&trace_types_lock); |
2b6080f2 SR |
3653 | if (unlikely(iter->trace->name != tr->current_trace->name)) |
3654 | *iter->trace = *tr->current_trace; | |
d7350c3f FW |
3655 | mutex_unlock(&trace_types_lock); |
3656 | ||
3657 | /* | |
3658 | * Avoid more than one consumer on a single file descriptor | |
3659 | * This is just a matter of traces coherency, the ring buffer itself | |
3660 | * is protected. | |
3661 | */ | |
3662 | mutex_lock(&iter->mutex); | |
ff98781b EGM |
3663 | if (iter->trace->read) { |
3664 | sret = iter->trace->read(iter, filp, ubuf, cnt, ppos); | |
3665 | if (sret) | |
3666 | goto out; | |
3667 | } | |
3668 | ||
3669 | waitagain: | |
3670 | sret = tracing_wait_pipe(filp); | |
3671 | if (sret <= 0) | |
3672 | goto out; | |
3673 | ||
b3806b43 | 3674 | /* stop when tracing is finished */ |
ff98781b EGM |
3675 | if (trace_empty(iter)) { |
3676 | sret = 0; | |
107bad8b | 3677 | goto out; |
ff98781b | 3678 | } |
b3806b43 SR |
3679 | |
3680 | if (cnt >= PAGE_SIZE) | |
3681 | cnt = PAGE_SIZE - 1; | |
3682 | ||
53d0aa77 | 3683 | /* reset all but tr, trace, and overruns */ |
53d0aa77 SR |
3684 | memset(&iter->seq, 0, |
3685 | sizeof(struct trace_iterator) - | |
3686 | offsetof(struct trace_iterator, seq)); | |
4823ed7e | 3687 | iter->pos = -1; |
b3806b43 | 3688 | |
4f535968 | 3689 | trace_event_read_lock(); |
7e53bd42 | 3690 | trace_access_lock(iter->cpu_file); |
955b61e5 | 3691 | while (trace_find_next_entry_inc(iter) != NULL) { |
2c4f035f | 3692 | enum print_line_t ret; |
088b1e42 SR |
3693 | int len = iter->seq.len; |
3694 | ||
f9896bf3 | 3695 | ret = print_trace_line(iter); |
2c4f035f | 3696 | if (ret == TRACE_TYPE_PARTIAL_LINE) { |
088b1e42 SR |
3697 | /* don't print partial lines */ |
3698 | iter->seq.len = len; | |
b3806b43 | 3699 | break; |
088b1e42 | 3700 | } |
b91facc3 FW |
3701 | if (ret != TRACE_TYPE_NO_CONSUME) |
3702 | trace_consume(iter); | |
b3806b43 SR |
3703 | |
3704 | if (iter->seq.len >= cnt) | |
3705 | break; | |
ee5e51f5 JO |
3706 | |
3707 | /* | |
3708 | * Setting the full flag means we reached the trace_seq buffer | |
3709 | * size and we should leave by partial output condition above. | |
3710 | * One of the trace_seq_* functions is not used properly. | |
3711 | */ | |
3712 | WARN_ONCE(iter->seq.full, "full flag set for trace type %d", | |
3713 | iter->ent->type); | |
b3806b43 | 3714 | } |
7e53bd42 | 3715 | trace_access_unlock(iter->cpu_file); |
4f535968 | 3716 | trace_event_read_unlock(); |
b3806b43 | 3717 | |
b3806b43 | 3718 | /* Now copy what we have to the user */ |
6c6c2796 PP |
3719 | sret = trace_seq_to_user(&iter->seq, ubuf, cnt); |
3720 | if (iter->seq.readpos >= iter->seq.len) | |
f9520750 | 3721 | trace_seq_init(&iter->seq); |
9ff4b974 PP |
3722 | |
3723 | /* | |
25985edc | 3724 | * If there was nothing to send to user, in spite of consuming trace |
9ff4b974 PP |
3725 | * entries, go back to wait for more entries. |
3726 | */ | |
6c6c2796 | 3727 | if (sret == -EBUSY) |
9ff4b974 | 3728 | goto waitagain; |
b3806b43 | 3729 | |
107bad8b | 3730 | out: |
d7350c3f | 3731 | mutex_unlock(&iter->mutex); |
107bad8b | 3732 | |
6c6c2796 | 3733 | return sret; |
b3806b43 SR |
3734 | } |
3735 | ||
3c56819b EGM |
3736 | static void tracing_pipe_buf_release(struct pipe_inode_info *pipe, |
3737 | struct pipe_buffer *buf) | |
3738 | { | |
3739 | __free_page(buf->page); | |
3740 | } | |
3741 | ||
3742 | static void tracing_spd_release_pipe(struct splice_pipe_desc *spd, | |
3743 | unsigned int idx) | |
3744 | { | |
3745 | __free_page(spd->pages[idx]); | |
3746 | } | |
3747 | ||
28dfef8f | 3748 | static const struct pipe_buf_operations tracing_pipe_buf_ops = { |
34cd4998 SR |
3749 | .can_merge = 0, |
3750 | .map = generic_pipe_buf_map, | |
3751 | .unmap = generic_pipe_buf_unmap, | |
3752 | .confirm = generic_pipe_buf_confirm, | |
3753 | .release = tracing_pipe_buf_release, | |
3754 | .steal = generic_pipe_buf_steal, | |
3755 | .get = generic_pipe_buf_get, | |
3c56819b EGM |
3756 | }; |
3757 | ||
34cd4998 | 3758 | static size_t |
fa7c7f6e | 3759 | tracing_fill_pipe_page(size_t rem, struct trace_iterator *iter) |
34cd4998 SR |
3760 | { |
3761 | size_t count; | |
3762 | int ret; | |
3763 | ||
3764 | /* Seq buffer is page-sized, exactly what we need. */ | |
3765 | for (;;) { | |
3766 | count = iter->seq.len; | |
3767 | ret = print_trace_line(iter); | |
3768 | count = iter->seq.len - count; | |
3769 | if (rem < count) { | |
3770 | rem = 0; | |
3771 | iter->seq.len -= count; | |
3772 | break; | |
3773 | } | |
3774 | if (ret == TRACE_TYPE_PARTIAL_LINE) { | |
3775 | iter->seq.len -= count; | |
3776 | break; | |
3777 | } | |
3778 | ||
74e7ff8c LJ |
3779 | if (ret != TRACE_TYPE_NO_CONSUME) |
3780 | trace_consume(iter); | |
34cd4998 | 3781 | rem -= count; |
955b61e5 | 3782 | if (!trace_find_next_entry_inc(iter)) { |
34cd4998 SR |
3783 | rem = 0; |
3784 | iter->ent = NULL; | |
3785 | break; | |
3786 | } | |
3787 | } | |
3788 | ||
3789 | return rem; | |
3790 | } | |
3791 | ||
3c56819b EGM |
3792 | static ssize_t tracing_splice_read_pipe(struct file *filp, |
3793 | loff_t *ppos, | |
3794 | struct pipe_inode_info *pipe, | |
3795 | size_t len, | |
3796 | unsigned int flags) | |
3797 | { | |
35f3d14d JA |
3798 | struct page *pages_def[PIPE_DEF_BUFFERS]; |
3799 | struct partial_page partial_def[PIPE_DEF_BUFFERS]; | |
3c56819b EGM |
3800 | struct trace_iterator *iter = filp->private_data; |
3801 | struct splice_pipe_desc spd = { | |
35f3d14d JA |
3802 | .pages = pages_def, |
3803 | .partial = partial_def, | |
34cd4998 | 3804 | .nr_pages = 0, /* This gets updated below. */ |
047fe360 | 3805 | .nr_pages_max = PIPE_DEF_BUFFERS, |
34cd4998 SR |
3806 | .flags = flags, |
3807 | .ops = &tracing_pipe_buf_ops, | |
3808 | .spd_release = tracing_spd_release_pipe, | |
3c56819b | 3809 | }; |
2b6080f2 | 3810 | struct trace_array *tr = iter->tr; |
3c56819b | 3811 | ssize_t ret; |
34cd4998 | 3812 | size_t rem; |
3c56819b EGM |
3813 | unsigned int i; |
3814 | ||
35f3d14d JA |
3815 | if (splice_grow_spd(pipe, &spd)) |
3816 | return -ENOMEM; | |
3817 | ||
d7350c3f | 3818 | /* copy the tracer to avoid using a global lock all around */ |
3c56819b | 3819 | mutex_lock(&trace_types_lock); |
2b6080f2 SR |
3820 | if (unlikely(iter->trace->name != tr->current_trace->name)) |
3821 | *iter->trace = *tr->current_trace; | |
d7350c3f FW |
3822 | mutex_unlock(&trace_types_lock); |
3823 | ||
3824 | mutex_lock(&iter->mutex); | |
3c56819b EGM |
3825 | |
3826 | if (iter->trace->splice_read) { | |
3827 | ret = iter->trace->splice_read(iter, filp, | |
3828 | ppos, pipe, len, flags); | |
3829 | if (ret) | |
34cd4998 | 3830 | goto out_err; |
3c56819b EGM |
3831 | } |
3832 | ||
3833 | ret = tracing_wait_pipe(filp); | |
3834 | if (ret <= 0) | |
34cd4998 | 3835 | goto out_err; |
3c56819b | 3836 | |
955b61e5 | 3837 | if (!iter->ent && !trace_find_next_entry_inc(iter)) { |
3c56819b | 3838 | ret = -EFAULT; |
34cd4998 | 3839 | goto out_err; |
3c56819b EGM |
3840 | } |
3841 | ||
4f535968 | 3842 | trace_event_read_lock(); |
7e53bd42 | 3843 | trace_access_lock(iter->cpu_file); |
4f535968 | 3844 | |
3c56819b | 3845 | /* Fill as many pages as possible. */ |
35f3d14d JA |
3846 | for (i = 0, rem = len; i < pipe->buffers && rem; i++) { |
3847 | spd.pages[i] = alloc_page(GFP_KERNEL); | |
3848 | if (!spd.pages[i]) | |
34cd4998 | 3849 | break; |
3c56819b | 3850 | |
fa7c7f6e | 3851 | rem = tracing_fill_pipe_page(rem, iter); |
3c56819b EGM |
3852 | |
3853 | /* Copy the data into the page, so we can start over. */ | |
3854 | ret = trace_seq_to_buffer(&iter->seq, | |
35f3d14d | 3855 | page_address(spd.pages[i]), |
3c56819b EGM |
3856 | iter->seq.len); |
3857 | if (ret < 0) { | |
35f3d14d | 3858 | __free_page(spd.pages[i]); |
3c56819b EGM |
3859 | break; |
3860 | } | |
35f3d14d JA |
3861 | spd.partial[i].offset = 0; |
3862 | spd.partial[i].len = iter->seq.len; | |
3c56819b | 3863 | |
f9520750 | 3864 | trace_seq_init(&iter->seq); |
3c56819b EGM |
3865 | } |
3866 | ||
7e53bd42 | 3867 | trace_access_unlock(iter->cpu_file); |
4f535968 | 3868 | trace_event_read_unlock(); |
d7350c3f | 3869 | mutex_unlock(&iter->mutex); |
3c56819b EGM |
3870 | |
3871 | spd.nr_pages = i; | |
3872 | ||
35f3d14d JA |
3873 | ret = splice_to_pipe(pipe, &spd); |
3874 | out: | |
047fe360 | 3875 | splice_shrink_spd(&spd); |
35f3d14d | 3876 | return ret; |
3c56819b | 3877 | |
34cd4998 | 3878 | out_err: |
d7350c3f | 3879 | mutex_unlock(&iter->mutex); |
35f3d14d | 3880 | goto out; |
3c56819b EGM |
3881 | } |
3882 | ||
a98a3c3f SR |
3883 | static ssize_t |
3884 | tracing_entries_read(struct file *filp, char __user *ubuf, | |
3885 | size_t cnt, loff_t *ppos) | |
3886 | { | |
2b6080f2 SR |
3887 | struct trace_cpu *tc = filp->private_data; |
3888 | struct trace_array *tr = tc->tr; | |
438ced17 VN |
3889 | char buf[64]; |
3890 | int r = 0; | |
3891 | ssize_t ret; | |
a98a3c3f | 3892 | |
db526ca3 | 3893 | mutex_lock(&trace_types_lock); |
438ced17 | 3894 | |
2b6080f2 | 3895 | if (tc->cpu == RING_BUFFER_ALL_CPUS) { |
438ced17 VN |
3896 | int cpu, buf_size_same; |
3897 | unsigned long size; | |
3898 | ||
3899 | size = 0; | |
3900 | buf_size_same = 1; | |
3901 | /* check if all cpu sizes are same */ | |
3902 | for_each_tracing_cpu(cpu) { | |
3903 | /* fill in the size from first enabled cpu */ | |
3904 | if (size == 0) | |
a7603ff4 SR |
3905 | size = per_cpu_ptr(tr->data, cpu)->entries; |
3906 | if (size != per_cpu_ptr(tr->data, cpu)->entries) { | |
438ced17 VN |
3907 | buf_size_same = 0; |
3908 | break; | |
3909 | } | |
3910 | } | |
3911 | ||
3912 | if (buf_size_same) { | |
3913 | if (!ring_buffer_expanded) | |
3914 | r = sprintf(buf, "%lu (expanded: %lu)\n", | |
3915 | size >> 10, | |
3916 | trace_buf_size >> 10); | |
3917 | else | |
3918 | r = sprintf(buf, "%lu\n", size >> 10); | |
3919 | } else | |
3920 | r = sprintf(buf, "X\n"); | |
3921 | } else | |
a7603ff4 | 3922 | r = sprintf(buf, "%lu\n", per_cpu_ptr(tr->data, tc->cpu)->entries >> 10); |
438ced17 | 3923 | |
db526ca3 SR |
3924 | mutex_unlock(&trace_types_lock); |
3925 | ||
438ced17 VN |
3926 | ret = simple_read_from_buffer(ubuf, cnt, ppos, buf, r); |
3927 | return ret; | |
a98a3c3f SR |
3928 | } |
3929 | ||
3930 | static ssize_t | |
3931 | tracing_entries_write(struct file *filp, const char __user *ubuf, | |
3932 | size_t cnt, loff_t *ppos) | |
3933 | { | |
2b6080f2 | 3934 | struct trace_cpu *tc = filp->private_data; |
a98a3c3f | 3935 | unsigned long val; |
4f271a2a | 3936 | int ret; |
a98a3c3f | 3937 | |
22fe9b54 PH |
3938 | ret = kstrtoul_from_user(ubuf, cnt, 10, &val); |
3939 | if (ret) | |
c6caeeb1 | 3940 | return ret; |
a98a3c3f SR |
3941 | |
3942 | /* must have at least 1 entry */ | |
3943 | if (!val) | |
3944 | return -EINVAL; | |
3945 | ||
1696b2b0 SR |
3946 | /* value is in KB */ |
3947 | val <<= 10; | |
3948 | ||
2b6080f2 | 3949 | ret = tracing_resize_ring_buffer(tc->tr, val, tc->cpu); |
4f271a2a VN |
3950 | if (ret < 0) |
3951 | return ret; | |
a98a3c3f | 3952 | |
cf8517cf | 3953 | *ppos += cnt; |
a98a3c3f | 3954 | |
4f271a2a VN |
3955 | return cnt; |
3956 | } | |
bf5e6519 | 3957 | |
f81ab074 VN |
3958 | static ssize_t |
3959 | tracing_total_entries_read(struct file *filp, char __user *ubuf, | |
3960 | size_t cnt, loff_t *ppos) | |
3961 | { | |
3962 | struct trace_array *tr = filp->private_data; | |
3963 | char buf[64]; | |
3964 | int r, cpu; | |
3965 | unsigned long size = 0, expanded_size = 0; | |
3966 | ||
3967 | mutex_lock(&trace_types_lock); | |
3968 | for_each_tracing_cpu(cpu) { | |
a7603ff4 | 3969 | size += per_cpu_ptr(tr->data, cpu)->entries >> 10; |
f81ab074 VN |
3970 | if (!ring_buffer_expanded) |
3971 | expanded_size += trace_buf_size >> 10; | |
3972 | } | |
3973 | if (ring_buffer_expanded) | |
3974 | r = sprintf(buf, "%lu\n", size); | |
3975 | else | |
3976 | r = sprintf(buf, "%lu (expanded: %lu)\n", size, expanded_size); | |
3977 | mutex_unlock(&trace_types_lock); | |
3978 | ||
3979 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, r); | |
3980 | } | |
3981 | ||
4f271a2a VN |
3982 | static ssize_t |
3983 | tracing_free_buffer_write(struct file *filp, const char __user *ubuf, | |
3984 | size_t cnt, loff_t *ppos) | |
3985 | { | |
3986 | /* | |
3987 | * There is no need to read what the user has written, this function | |
3988 | * is just to make sure that there is no error when "echo" is used | |
3989 | */ | |
3990 | ||
3991 | *ppos += cnt; | |
a98a3c3f SR |
3992 | |
3993 | return cnt; | |
3994 | } | |
3995 | ||
4f271a2a VN |
3996 | static int |
3997 | tracing_free_buffer_release(struct inode *inode, struct file *filp) | |
3998 | { | |
2b6080f2 SR |
3999 | struct trace_array *tr = inode->i_private; |
4000 | ||
cf30cf67 SR |
4001 | /* disable tracing ? */ |
4002 | if (trace_flags & TRACE_ITER_STOP_ON_FREE) | |
4003 | tracing_off(); | |
4f271a2a | 4004 | /* resize the ring buffer to 0 */ |
2b6080f2 | 4005 | tracing_resize_ring_buffer(tr, 0, RING_BUFFER_ALL_CPUS); |
4f271a2a VN |
4006 | |
4007 | return 0; | |
4008 | } | |
4009 | ||
5bf9a1ee PP |
4010 | static ssize_t |
4011 | tracing_mark_write(struct file *filp, const char __user *ubuf, | |
4012 | size_t cnt, loff_t *fpos) | |
4013 | { | |
d696b58c SR |
4014 | unsigned long addr = (unsigned long)ubuf; |
4015 | struct ring_buffer_event *event; | |
4016 | struct ring_buffer *buffer; | |
4017 | struct print_entry *entry; | |
4018 | unsigned long irq_flags; | |
4019 | struct page *pages[2]; | |
6edb2a8a | 4020 | void *map_page[2]; |
d696b58c SR |
4021 | int nr_pages = 1; |
4022 | ssize_t written; | |
d696b58c SR |
4023 | int offset; |
4024 | int size; | |
4025 | int len; | |
4026 | int ret; | |
6edb2a8a | 4027 | int i; |
5bf9a1ee | 4028 | |
c76f0694 | 4029 | if (tracing_disabled) |
5bf9a1ee PP |
4030 | return -EINVAL; |
4031 | ||
5224c3a3 MSB |
4032 | if (!(trace_flags & TRACE_ITER_MARKERS)) |
4033 | return -EINVAL; | |
4034 | ||
5bf9a1ee PP |
4035 | if (cnt > TRACE_BUF_SIZE) |
4036 | cnt = TRACE_BUF_SIZE; | |
4037 | ||
d696b58c SR |
4038 | /* |
4039 | * Userspace is injecting traces into the kernel trace buffer. | |
4040 | * We want to be as non intrusive as possible. | |
4041 | * To do so, we do not want to allocate any special buffers | |
4042 | * or take any locks, but instead write the userspace data | |
4043 | * straight into the ring buffer. | |
4044 | * | |
4045 | * First we need to pin the userspace buffer into memory, | |
4046 | * which, most likely it is, because it just referenced it. | |
4047 | * But there's no guarantee that it is. By using get_user_pages_fast() | |
4048 | * and kmap_atomic/kunmap_atomic() we can get access to the | |
4049 | * pages directly. We then write the data directly into the | |
4050 | * ring buffer. | |
4051 | */ | |
4052 | BUILD_BUG_ON(TRACE_BUF_SIZE >= PAGE_SIZE); | |
5bf9a1ee | 4053 | |
d696b58c SR |
4054 | /* check if we cross pages */ |
4055 | if ((addr & PAGE_MASK) != ((addr + cnt) & PAGE_MASK)) | |
4056 | nr_pages = 2; | |
4057 | ||
4058 | offset = addr & (PAGE_SIZE - 1); | |
4059 | addr &= PAGE_MASK; | |
4060 | ||
4061 | ret = get_user_pages_fast(addr, nr_pages, 0, pages); | |
4062 | if (ret < nr_pages) { | |
4063 | while (--ret >= 0) | |
4064 | put_page(pages[ret]); | |
4065 | written = -EFAULT; | |
4066 | goto out; | |
5bf9a1ee | 4067 | } |
d696b58c | 4068 | |
6edb2a8a SR |
4069 | for (i = 0; i < nr_pages; i++) |
4070 | map_page[i] = kmap_atomic(pages[i]); | |
d696b58c SR |
4071 | |
4072 | local_save_flags(irq_flags); | |
4073 | size = sizeof(*entry) + cnt + 2; /* possible \n added */ | |
4074 | buffer = global_trace.buffer; | |
4075 | event = trace_buffer_lock_reserve(buffer, TRACE_PRINT, size, | |
4076 | irq_flags, preempt_count()); | |
4077 | if (!event) { | |
4078 | /* Ring buffer disabled, return as if not open for write */ | |
4079 | written = -EBADF; | |
4080 | goto out_unlock; | |
5bf9a1ee | 4081 | } |
d696b58c SR |
4082 | |
4083 | entry = ring_buffer_event_data(event); | |
4084 | entry->ip = _THIS_IP_; | |
4085 | ||
4086 | if (nr_pages == 2) { | |
4087 | len = PAGE_SIZE - offset; | |
6edb2a8a SR |
4088 | memcpy(&entry->buf, map_page[0] + offset, len); |
4089 | memcpy(&entry->buf[len], map_page[1], cnt - len); | |
c13d2f7c | 4090 | } else |
6edb2a8a | 4091 | memcpy(&entry->buf, map_page[0] + offset, cnt); |
5bf9a1ee | 4092 | |
d696b58c SR |
4093 | if (entry->buf[cnt - 1] != '\n') { |
4094 | entry->buf[cnt] = '\n'; | |
4095 | entry->buf[cnt + 1] = '\0'; | |
4096 | } else | |
4097 | entry->buf[cnt] = '\0'; | |
4098 | ||
7ffbd48d | 4099 | __buffer_unlock_commit(buffer, event); |
5bf9a1ee | 4100 | |
d696b58c | 4101 | written = cnt; |
5bf9a1ee | 4102 | |
d696b58c | 4103 | *fpos += written; |
1aa54bca | 4104 | |
d696b58c | 4105 | out_unlock: |
6edb2a8a SR |
4106 | for (i = 0; i < nr_pages; i++){ |
4107 | kunmap_atomic(map_page[i]); | |
4108 | put_page(pages[i]); | |
4109 | } | |
d696b58c | 4110 | out: |
1aa54bca | 4111 | return written; |
5bf9a1ee PP |
4112 | } |
4113 | ||
13f16d20 | 4114 | static int tracing_clock_show(struct seq_file *m, void *v) |
5079f326 | 4115 | { |
2b6080f2 | 4116 | struct trace_array *tr = m->private; |
5079f326 Z |
4117 | int i; |
4118 | ||
4119 | for (i = 0; i < ARRAY_SIZE(trace_clocks); i++) | |
13f16d20 | 4120 | seq_printf(m, |
5079f326 | 4121 | "%s%s%s%s", i ? " " : "", |
2b6080f2 SR |
4122 | i == tr->clock_id ? "[" : "", trace_clocks[i].name, |
4123 | i == tr->clock_id ? "]" : ""); | |
13f16d20 | 4124 | seq_putc(m, '\n'); |
5079f326 | 4125 | |
13f16d20 | 4126 | return 0; |
5079f326 Z |
4127 | } |
4128 | ||
4129 | static ssize_t tracing_clock_write(struct file *filp, const char __user *ubuf, | |
4130 | size_t cnt, loff_t *fpos) | |
4131 | { | |
2b6080f2 SR |
4132 | struct seq_file *m = filp->private_data; |
4133 | struct trace_array *tr = m->private; | |
5079f326 Z |
4134 | char buf[64]; |
4135 | const char *clockstr; | |
4136 | int i; | |
4137 | ||
4138 | if (cnt >= sizeof(buf)) | |
4139 | return -EINVAL; | |
4140 | ||
4141 | if (copy_from_user(&buf, ubuf, cnt)) | |
4142 | return -EFAULT; | |
4143 | ||
4144 | buf[cnt] = 0; | |
4145 | ||
4146 | clockstr = strstrip(buf); | |
4147 | ||
4148 | for (i = 0; i < ARRAY_SIZE(trace_clocks); i++) { | |
4149 | if (strcmp(trace_clocks[i].name, clockstr) == 0) | |
4150 | break; | |
4151 | } | |
4152 | if (i == ARRAY_SIZE(trace_clocks)) | |
4153 | return -EINVAL; | |
4154 | ||
5079f326 Z |
4155 | mutex_lock(&trace_types_lock); |
4156 | ||
2b6080f2 SR |
4157 | tr->clock_id = i; |
4158 | ||
4159 | ring_buffer_set_clock(tr->buffer, trace_clocks[i].func); | |
4160 | if (tr->flags & TRACE_ARRAY_FL_GLOBAL && max_tr.buffer) | |
5079f326 Z |
4161 | ring_buffer_set_clock(max_tr.buffer, trace_clocks[i].func); |
4162 | ||
60303ed3 DS |
4163 | /* |
4164 | * New clock may not be consistent with the previous clock. | |
4165 | * Reset the buffer so that it doesn't have incomparable timestamps. | |
4166 | */ | |
4167 | tracing_reset_online_cpus(&global_trace); | |
84c6cf0d | 4168 | tracing_reset_online_cpus(&max_tr); |
60303ed3 | 4169 | |
5079f326 Z |
4170 | mutex_unlock(&trace_types_lock); |
4171 | ||
4172 | *fpos += cnt; | |
4173 | ||
4174 | return cnt; | |
4175 | } | |
4176 | ||
13f16d20 LZ |
4177 | static int tracing_clock_open(struct inode *inode, struct file *file) |
4178 | { | |
4179 | if (tracing_disabled) | |
4180 | return -ENODEV; | |
2b6080f2 SR |
4181 | |
4182 | return single_open(file, tracing_clock_show, inode->i_private); | |
13f16d20 LZ |
4183 | } |
4184 | ||
debdd57f HT |
4185 | #ifdef CONFIG_TRACER_SNAPSHOT |
4186 | static int tracing_snapshot_open(struct inode *inode, struct file *file) | |
4187 | { | |
2b6080f2 | 4188 | struct trace_cpu *tc = inode->i_private; |
debdd57f | 4189 | struct trace_iterator *iter; |
2b6080f2 | 4190 | struct seq_file *m; |
debdd57f HT |
4191 | int ret = 0; |
4192 | ||
4193 | if (file->f_mode & FMODE_READ) { | |
4194 | iter = __tracing_open(inode, file, true); | |
4195 | if (IS_ERR(iter)) | |
4196 | ret = PTR_ERR(iter); | |
2b6080f2 SR |
4197 | } else { |
4198 | /* Writes still need the seq_file to hold the private data */ | |
4199 | m = kzalloc(sizeof(*m), GFP_KERNEL); | |
4200 | if (!m) | |
4201 | return -ENOMEM; | |
4202 | iter = kzalloc(sizeof(*iter), GFP_KERNEL); | |
4203 | if (!iter) { | |
4204 | kfree(m); | |
4205 | return -ENOMEM; | |
4206 | } | |
4207 | iter->tr = tc->tr; | |
4208 | m->private = iter; | |
4209 | file->private_data = m; | |
debdd57f | 4210 | } |
2b6080f2 | 4211 | |
debdd57f HT |
4212 | return ret; |
4213 | } | |
4214 | ||
4215 | static ssize_t | |
4216 | tracing_snapshot_write(struct file *filp, const char __user *ubuf, size_t cnt, | |
4217 | loff_t *ppos) | |
4218 | { | |
2b6080f2 SR |
4219 | struct seq_file *m = filp->private_data; |
4220 | struct trace_iterator *iter = m->private; | |
4221 | struct trace_array *tr = iter->tr; | |
debdd57f HT |
4222 | unsigned long val; |
4223 | int ret; | |
4224 | ||
4225 | ret = tracing_update_buffers(); | |
4226 | if (ret < 0) | |
4227 | return ret; | |
4228 | ||
4229 | ret = kstrtoul_from_user(ubuf, cnt, 10, &val); | |
4230 | if (ret) | |
4231 | return ret; | |
4232 | ||
4233 | mutex_lock(&trace_types_lock); | |
4234 | ||
2b6080f2 | 4235 | if (tr->current_trace->use_max_tr) { |
debdd57f HT |
4236 | ret = -EBUSY; |
4237 | goto out; | |
4238 | } | |
4239 | ||
4240 | switch (val) { | |
4241 | case 0: | |
2b6080f2 | 4242 | if (tr->current_trace->allocated_snapshot) { |
debdd57f HT |
4243 | /* free spare buffer */ |
4244 | ring_buffer_resize(max_tr.buffer, 1, | |
4245 | RING_BUFFER_ALL_CPUS); | |
4246 | set_buffer_entries(&max_tr, 1); | |
4247 | tracing_reset_online_cpus(&max_tr); | |
2b6080f2 | 4248 | tr->current_trace->allocated_snapshot = false; |
debdd57f HT |
4249 | } |
4250 | break; | |
4251 | case 1: | |
2b6080f2 | 4252 | if (!tr->current_trace->allocated_snapshot) { |
debdd57f HT |
4253 | /* allocate spare buffer */ |
4254 | ret = resize_buffer_duplicate_size(&max_tr, | |
4255 | &global_trace, RING_BUFFER_ALL_CPUS); | |
4256 | if (ret < 0) | |
4257 | break; | |
2b6080f2 | 4258 | tr->current_trace->allocated_snapshot = true; |
debdd57f HT |
4259 | } |
4260 | ||
4261 | local_irq_disable(); | |
4262 | /* Now, we're going to swap */ | |
4263 | update_max_tr(&global_trace, current, smp_processor_id()); | |
4264 | local_irq_enable(); | |
4265 | break; | |
4266 | default: | |
2b6080f2 | 4267 | if (tr->current_trace->allocated_snapshot) |
debdd57f | 4268 | tracing_reset_online_cpus(&max_tr); |
debdd57f HT |
4269 | break; |
4270 | } | |
4271 | ||
4272 | if (ret >= 0) { | |
4273 | *ppos += cnt; | |
4274 | ret = cnt; | |
4275 | } | |
4276 | out: | |
4277 | mutex_unlock(&trace_types_lock); | |
4278 | return ret; | |
4279 | } | |
2b6080f2 SR |
4280 | |
4281 | static int tracing_snapshot_release(struct inode *inode, struct file *file) | |
4282 | { | |
4283 | struct seq_file *m = file->private_data; | |
4284 | ||
4285 | if (file->f_mode & FMODE_READ) | |
4286 | return tracing_release(inode, file); | |
4287 | ||
4288 | /* If write only, the seq_file is just a stub */ | |
4289 | if (m) | |
4290 | kfree(m->private); | |
4291 | kfree(m); | |
4292 | ||
4293 | return 0; | |
4294 | } | |
4295 | ||
debdd57f HT |
4296 | #endif /* CONFIG_TRACER_SNAPSHOT */ |
4297 | ||
4298 | ||
5e2336a0 | 4299 | static const struct file_operations tracing_max_lat_fops = { |
4bf39a94 IM |
4300 | .open = tracing_open_generic, |
4301 | .read = tracing_max_lat_read, | |
4302 | .write = tracing_max_lat_write, | |
b444786f | 4303 | .llseek = generic_file_llseek, |
bc0c38d1 SR |
4304 | }; |
4305 | ||
5e2336a0 | 4306 | static const struct file_operations set_tracer_fops = { |
4bf39a94 IM |
4307 | .open = tracing_open_generic, |
4308 | .read = tracing_set_trace_read, | |
4309 | .write = tracing_set_trace_write, | |
b444786f | 4310 | .llseek = generic_file_llseek, |
bc0c38d1 SR |
4311 | }; |
4312 | ||
5e2336a0 | 4313 | static const struct file_operations tracing_pipe_fops = { |
4bf39a94 | 4314 | .open = tracing_open_pipe, |
2a2cc8f7 | 4315 | .poll = tracing_poll_pipe, |
4bf39a94 | 4316 | .read = tracing_read_pipe, |
3c56819b | 4317 | .splice_read = tracing_splice_read_pipe, |
4bf39a94 | 4318 | .release = tracing_release_pipe, |
b444786f | 4319 | .llseek = no_llseek, |
b3806b43 SR |
4320 | }; |
4321 | ||
5e2336a0 | 4322 | static const struct file_operations tracing_entries_fops = { |
2b6080f2 | 4323 | .open = tracing_open_generic, |
a98a3c3f SR |
4324 | .read = tracing_entries_read, |
4325 | .write = tracing_entries_write, | |
b444786f | 4326 | .llseek = generic_file_llseek, |
a98a3c3f SR |
4327 | }; |
4328 | ||
f81ab074 VN |
4329 | static const struct file_operations tracing_total_entries_fops = { |
4330 | .open = tracing_open_generic, | |
4331 | .read = tracing_total_entries_read, | |
4332 | .llseek = generic_file_llseek, | |
4333 | }; | |
4334 | ||
4f271a2a VN |
4335 | static const struct file_operations tracing_free_buffer_fops = { |
4336 | .write = tracing_free_buffer_write, | |
4337 | .release = tracing_free_buffer_release, | |
4338 | }; | |
4339 | ||
5e2336a0 | 4340 | static const struct file_operations tracing_mark_fops = { |
43a15386 | 4341 | .open = tracing_open_generic, |
5bf9a1ee | 4342 | .write = tracing_mark_write, |
b444786f | 4343 | .llseek = generic_file_llseek, |
5bf9a1ee PP |
4344 | }; |
4345 | ||
5079f326 | 4346 | static const struct file_operations trace_clock_fops = { |
13f16d20 LZ |
4347 | .open = tracing_clock_open, |
4348 | .read = seq_read, | |
4349 | .llseek = seq_lseek, | |
4350 | .release = single_release, | |
5079f326 Z |
4351 | .write = tracing_clock_write, |
4352 | }; | |
4353 | ||
debdd57f HT |
4354 | #ifdef CONFIG_TRACER_SNAPSHOT |
4355 | static const struct file_operations snapshot_fops = { | |
4356 | .open = tracing_snapshot_open, | |
4357 | .read = seq_read, | |
4358 | .write = tracing_snapshot_write, | |
4359 | .llseek = tracing_seek, | |
2b6080f2 | 4360 | .release = tracing_snapshot_release, |
debdd57f HT |
4361 | }; |
4362 | #endif /* CONFIG_TRACER_SNAPSHOT */ | |
4363 | ||
2cadf913 SR |
4364 | struct ftrace_buffer_info { |
4365 | struct trace_array *tr; | |
4366 | void *spare; | |
4367 | int cpu; | |
4368 | unsigned int read; | |
4369 | }; | |
4370 | ||
4371 | static int tracing_buffers_open(struct inode *inode, struct file *filp) | |
4372 | { | |
2b6080f2 SR |
4373 | struct trace_cpu *tc = inode->i_private; |
4374 | struct trace_array *tr = tc->tr; | |
2cadf913 SR |
4375 | struct ftrace_buffer_info *info; |
4376 | ||
4377 | if (tracing_disabled) | |
4378 | return -ENODEV; | |
4379 | ||
4380 | info = kzalloc(sizeof(*info), GFP_KERNEL); | |
4381 | if (!info) | |
4382 | return -ENOMEM; | |
4383 | ||
2b6080f2 SR |
4384 | info->tr = tr; |
4385 | info->cpu = tc->cpu; | |
ddd538f3 | 4386 | info->spare = NULL; |
2cadf913 SR |
4387 | /* Force reading ring buffer for first read */ |
4388 | info->read = (unsigned int)-1; | |
2cadf913 SR |
4389 | |
4390 | filp->private_data = info; | |
4391 | ||
d1e7e02f | 4392 | return nonseekable_open(inode, filp); |
2cadf913 SR |
4393 | } |
4394 | ||
4395 | static ssize_t | |
4396 | tracing_buffers_read(struct file *filp, char __user *ubuf, | |
4397 | size_t count, loff_t *ppos) | |
4398 | { | |
4399 | struct ftrace_buffer_info *info = filp->private_data; | |
2cadf913 SR |
4400 | ssize_t ret; |
4401 | size_t size; | |
4402 | ||
2dc5d12b SR |
4403 | if (!count) |
4404 | return 0; | |
4405 | ||
ddd538f3 | 4406 | if (!info->spare) |
7ea59064 | 4407 | info->spare = ring_buffer_alloc_read_page(info->tr->buffer, info->cpu); |
ddd538f3 LJ |
4408 | if (!info->spare) |
4409 | return -ENOMEM; | |
4410 | ||
2cadf913 SR |
4411 | /* Do we have previous read data to read? */ |
4412 | if (info->read < PAGE_SIZE) | |
4413 | goto read; | |
4414 | ||
7e53bd42 | 4415 | trace_access_lock(info->cpu); |
2cadf913 SR |
4416 | ret = ring_buffer_read_page(info->tr->buffer, |
4417 | &info->spare, | |
4418 | count, | |
4419 | info->cpu, 0); | |
7e53bd42 | 4420 | trace_access_unlock(info->cpu); |
2cadf913 SR |
4421 | if (ret < 0) |
4422 | return 0; | |
4423 | ||
436fc280 SR |
4424 | info->read = 0; |
4425 | ||
2cadf913 SR |
4426 | read: |
4427 | size = PAGE_SIZE - info->read; | |
4428 | if (size > count) | |
4429 | size = count; | |
4430 | ||
4431 | ret = copy_to_user(ubuf, info->spare + info->read, size); | |
2dc5d12b | 4432 | if (ret == size) |
2cadf913 | 4433 | return -EFAULT; |
2dc5d12b SR |
4434 | size -= ret; |
4435 | ||
2cadf913 SR |
4436 | *ppos += size; |
4437 | info->read += size; | |
4438 | ||
4439 | return size; | |
4440 | } | |
4441 | ||
4442 | static int tracing_buffers_release(struct inode *inode, struct file *file) | |
4443 | { | |
4444 | struct ftrace_buffer_info *info = file->private_data; | |
4445 | ||
ddd538f3 LJ |
4446 | if (info->spare) |
4447 | ring_buffer_free_read_page(info->tr->buffer, info->spare); | |
2cadf913 SR |
4448 | kfree(info); |
4449 | ||
4450 | return 0; | |
4451 | } | |
4452 | ||
4453 | struct buffer_ref { | |
4454 | struct ring_buffer *buffer; | |
4455 | void *page; | |
4456 | int ref; | |
4457 | }; | |
4458 | ||
4459 | static void buffer_pipe_buf_release(struct pipe_inode_info *pipe, | |
4460 | struct pipe_buffer *buf) | |
4461 | { | |
4462 | struct buffer_ref *ref = (struct buffer_ref *)buf->private; | |
4463 | ||
4464 | if (--ref->ref) | |
4465 | return; | |
4466 | ||
4467 | ring_buffer_free_read_page(ref->buffer, ref->page); | |
4468 | kfree(ref); | |
4469 | buf->private = 0; | |
4470 | } | |
4471 | ||
2cadf913 SR |
4472 | static void buffer_pipe_buf_get(struct pipe_inode_info *pipe, |
4473 | struct pipe_buffer *buf) | |
4474 | { | |
4475 | struct buffer_ref *ref = (struct buffer_ref *)buf->private; | |
4476 | ||
4477 | ref->ref++; | |
4478 | } | |
4479 | ||
4480 | /* Pipe buffer operations for a buffer. */ | |
28dfef8f | 4481 | static const struct pipe_buf_operations buffer_pipe_buf_ops = { |
2cadf913 SR |
4482 | .can_merge = 0, |
4483 | .map = generic_pipe_buf_map, | |
4484 | .unmap = generic_pipe_buf_unmap, | |
4485 | .confirm = generic_pipe_buf_confirm, | |
4486 | .release = buffer_pipe_buf_release, | |
d55cb6cf | 4487 | .steal = generic_pipe_buf_steal, |
2cadf913 SR |
4488 | .get = buffer_pipe_buf_get, |
4489 | }; | |
4490 | ||
4491 | /* | |
4492 | * Callback from splice_to_pipe(), if we need to release some pages | |
4493 | * at the end of the spd in case we error'ed out in filling the pipe. | |
4494 | */ | |
4495 | static void buffer_spd_release(struct splice_pipe_desc *spd, unsigned int i) | |
4496 | { | |
4497 | struct buffer_ref *ref = | |
4498 | (struct buffer_ref *)spd->partial[i].private; | |
4499 | ||
4500 | if (--ref->ref) | |
4501 | return; | |
4502 | ||
4503 | ring_buffer_free_read_page(ref->buffer, ref->page); | |
4504 | kfree(ref); | |
4505 | spd->partial[i].private = 0; | |
4506 | } | |
4507 | ||
4508 | static ssize_t | |
4509 | tracing_buffers_splice_read(struct file *file, loff_t *ppos, | |
4510 | struct pipe_inode_info *pipe, size_t len, | |
4511 | unsigned int flags) | |
4512 | { | |
4513 | struct ftrace_buffer_info *info = file->private_data; | |
35f3d14d JA |
4514 | struct partial_page partial_def[PIPE_DEF_BUFFERS]; |
4515 | struct page *pages_def[PIPE_DEF_BUFFERS]; | |
2cadf913 | 4516 | struct splice_pipe_desc spd = { |
35f3d14d JA |
4517 | .pages = pages_def, |
4518 | .partial = partial_def, | |
047fe360 | 4519 | .nr_pages_max = PIPE_DEF_BUFFERS, |
2cadf913 SR |
4520 | .flags = flags, |
4521 | .ops = &buffer_pipe_buf_ops, | |
4522 | .spd_release = buffer_spd_release, | |
4523 | }; | |
4524 | struct buffer_ref *ref; | |
93459c6c | 4525 | int entries, size, i; |
2cadf913 SR |
4526 | size_t ret; |
4527 | ||
35f3d14d JA |
4528 | if (splice_grow_spd(pipe, &spd)) |
4529 | return -ENOMEM; | |
4530 | ||
93cfb3c9 | 4531 | if (*ppos & (PAGE_SIZE - 1)) { |
35f3d14d JA |
4532 | ret = -EINVAL; |
4533 | goto out; | |
93cfb3c9 LJ |
4534 | } |
4535 | ||
4536 | if (len & (PAGE_SIZE - 1)) { | |
35f3d14d JA |
4537 | if (len < PAGE_SIZE) { |
4538 | ret = -EINVAL; | |
4539 | goto out; | |
4540 | } | |
93cfb3c9 LJ |
4541 | len &= PAGE_MASK; |
4542 | } | |
4543 | ||
7e53bd42 | 4544 | trace_access_lock(info->cpu); |
93459c6c SR |
4545 | entries = ring_buffer_entries_cpu(info->tr->buffer, info->cpu); |
4546 | ||
35f3d14d | 4547 | for (i = 0; i < pipe->buffers && len && entries; i++, len -= PAGE_SIZE) { |
2cadf913 SR |
4548 | struct page *page; |
4549 | int r; | |
4550 | ||
4551 | ref = kzalloc(sizeof(*ref), GFP_KERNEL); | |
4552 | if (!ref) | |
4553 | break; | |
4554 | ||
7267fa68 | 4555 | ref->ref = 1; |
2cadf913 | 4556 | ref->buffer = info->tr->buffer; |
7ea59064 | 4557 | ref->page = ring_buffer_alloc_read_page(ref->buffer, info->cpu); |
2cadf913 SR |
4558 | if (!ref->page) { |
4559 | kfree(ref); | |
4560 | break; | |
4561 | } | |
4562 | ||
4563 | r = ring_buffer_read_page(ref->buffer, &ref->page, | |
f2957f1f | 4564 | len, info->cpu, 1); |
2cadf913 | 4565 | if (r < 0) { |
7ea59064 | 4566 | ring_buffer_free_read_page(ref->buffer, ref->page); |
2cadf913 SR |
4567 | kfree(ref); |
4568 | break; | |
4569 | } | |
4570 | ||
4571 | /* | |
4572 | * zero out any left over data, this is going to | |
4573 | * user land. | |
4574 | */ | |
4575 | size = ring_buffer_page_len(ref->page); | |
4576 | if (size < PAGE_SIZE) | |
4577 | memset(ref->page + size, 0, PAGE_SIZE - size); | |
4578 | ||
4579 | page = virt_to_page(ref->page); | |
4580 | ||
4581 | spd.pages[i] = page; | |
4582 | spd.partial[i].len = PAGE_SIZE; | |
4583 | spd.partial[i].offset = 0; | |
4584 | spd.partial[i].private = (unsigned long)ref; | |
4585 | spd.nr_pages++; | |
93cfb3c9 | 4586 | *ppos += PAGE_SIZE; |
93459c6c SR |
4587 | |
4588 | entries = ring_buffer_entries_cpu(info->tr->buffer, info->cpu); | |
2cadf913 SR |
4589 | } |
4590 | ||
7e53bd42 | 4591 | trace_access_unlock(info->cpu); |
2cadf913 SR |
4592 | spd.nr_pages = i; |
4593 | ||
4594 | /* did we read anything? */ | |
4595 | if (!spd.nr_pages) { | |
4596 | if (flags & SPLICE_F_NONBLOCK) | |
4597 | ret = -EAGAIN; | |
4598 | else | |
4599 | ret = 0; | |
4600 | /* TODO: block */ | |
35f3d14d | 4601 | goto out; |
2cadf913 SR |
4602 | } |
4603 | ||
4604 | ret = splice_to_pipe(pipe, &spd); | |
047fe360 | 4605 | splice_shrink_spd(&spd); |
35f3d14d | 4606 | out: |
2cadf913 SR |
4607 | return ret; |
4608 | } | |
4609 | ||
4610 | static const struct file_operations tracing_buffers_fops = { | |
4611 | .open = tracing_buffers_open, | |
4612 | .read = tracing_buffers_read, | |
4613 | .release = tracing_buffers_release, | |
4614 | .splice_read = tracing_buffers_splice_read, | |
4615 | .llseek = no_llseek, | |
4616 | }; | |
4617 | ||
c8d77183 SR |
4618 | static ssize_t |
4619 | tracing_stats_read(struct file *filp, char __user *ubuf, | |
4620 | size_t count, loff_t *ppos) | |
4621 | { | |
2b6080f2 SR |
4622 | struct trace_cpu *tc = filp->private_data; |
4623 | struct trace_array *tr = tc->tr; | |
c8d77183 SR |
4624 | struct trace_seq *s; |
4625 | unsigned long cnt; | |
c64e148a VN |
4626 | unsigned long long t; |
4627 | unsigned long usec_rem; | |
2b6080f2 | 4628 | int cpu = tc->cpu; |
c8d77183 | 4629 | |
e4f2d10f | 4630 | s = kmalloc(sizeof(*s), GFP_KERNEL); |
c8d77183 | 4631 | if (!s) |
a646365c | 4632 | return -ENOMEM; |
c8d77183 SR |
4633 | |
4634 | trace_seq_init(s); | |
4635 | ||
4636 | cnt = ring_buffer_entries_cpu(tr->buffer, cpu); | |
4637 | trace_seq_printf(s, "entries: %ld\n", cnt); | |
4638 | ||
4639 | cnt = ring_buffer_overrun_cpu(tr->buffer, cpu); | |
4640 | trace_seq_printf(s, "overrun: %ld\n", cnt); | |
4641 | ||
4642 | cnt = ring_buffer_commit_overrun_cpu(tr->buffer, cpu); | |
4643 | trace_seq_printf(s, "commit overrun: %ld\n", cnt); | |
4644 | ||
c64e148a VN |
4645 | cnt = ring_buffer_bytes_cpu(tr->buffer, cpu); |
4646 | trace_seq_printf(s, "bytes: %ld\n", cnt); | |
4647 | ||
11043d8b YY |
4648 | if (trace_clocks[trace_clock_id].in_ns) { |
4649 | /* local or global for trace_clock */ | |
4650 | t = ns2usecs(ring_buffer_oldest_event_ts(tr->buffer, cpu)); | |
4651 | usec_rem = do_div(t, USEC_PER_SEC); | |
4652 | trace_seq_printf(s, "oldest event ts: %5llu.%06lu\n", | |
4653 | t, usec_rem); | |
4654 | ||
4655 | t = ns2usecs(ring_buffer_time_stamp(tr->buffer, cpu)); | |
4656 | usec_rem = do_div(t, USEC_PER_SEC); | |
4657 | trace_seq_printf(s, "now ts: %5llu.%06lu\n", t, usec_rem); | |
4658 | } else { | |
4659 | /* counter or tsc mode for trace_clock */ | |
4660 | trace_seq_printf(s, "oldest event ts: %llu\n", | |
4661 | ring_buffer_oldest_event_ts(tr->buffer, cpu)); | |
c64e148a | 4662 | |
11043d8b YY |
4663 | trace_seq_printf(s, "now ts: %llu\n", |
4664 | ring_buffer_time_stamp(tr->buffer, cpu)); | |
4665 | } | |
c64e148a | 4666 | |
884bfe89 SP |
4667 | cnt = ring_buffer_dropped_events_cpu(tr->buffer, cpu); |
4668 | trace_seq_printf(s, "dropped events: %ld\n", cnt); | |
4669 | ||
ad964704 SRRH |
4670 | cnt = ring_buffer_read_events_cpu(tr->buffer, cpu); |
4671 | trace_seq_printf(s, "read events: %ld\n", cnt); | |
4672 | ||
c8d77183 SR |
4673 | count = simple_read_from_buffer(ubuf, count, ppos, s->buffer, s->len); |
4674 | ||
4675 | kfree(s); | |
4676 | ||
4677 | return count; | |
4678 | } | |
4679 | ||
4680 | static const struct file_operations tracing_stats_fops = { | |
4681 | .open = tracing_open_generic, | |
4682 | .read = tracing_stats_read, | |
b444786f | 4683 | .llseek = generic_file_llseek, |
c8d77183 SR |
4684 | }; |
4685 | ||
bc0c38d1 SR |
4686 | #ifdef CONFIG_DYNAMIC_FTRACE |
4687 | ||
b807c3d0 SR |
4688 | int __weak ftrace_arch_read_dyn_info(char *buf, int size) |
4689 | { | |
4690 | return 0; | |
4691 | } | |
4692 | ||
bc0c38d1 | 4693 | static ssize_t |
b807c3d0 | 4694 | tracing_read_dyn_info(struct file *filp, char __user *ubuf, |
bc0c38d1 SR |
4695 | size_t cnt, loff_t *ppos) |
4696 | { | |
a26a2a27 SR |
4697 | static char ftrace_dyn_info_buffer[1024]; |
4698 | static DEFINE_MUTEX(dyn_info_mutex); | |
bc0c38d1 | 4699 | unsigned long *p = filp->private_data; |
b807c3d0 | 4700 | char *buf = ftrace_dyn_info_buffer; |
a26a2a27 | 4701 | int size = ARRAY_SIZE(ftrace_dyn_info_buffer); |
bc0c38d1 SR |
4702 | int r; |
4703 | ||
b807c3d0 SR |
4704 | mutex_lock(&dyn_info_mutex); |
4705 | r = sprintf(buf, "%ld ", *p); | |
4bf39a94 | 4706 | |
a26a2a27 | 4707 | r += ftrace_arch_read_dyn_info(buf+r, (size-1)-r); |
b807c3d0 SR |
4708 | buf[r++] = '\n'; |
4709 | ||
4710 | r = simple_read_from_buffer(ubuf, cnt, ppos, buf, r); | |
4711 | ||
4712 | mutex_unlock(&dyn_info_mutex); | |
4713 | ||
4714 | return r; | |
bc0c38d1 SR |
4715 | } |
4716 | ||
5e2336a0 | 4717 | static const struct file_operations tracing_dyn_info_fops = { |
4bf39a94 | 4718 | .open = tracing_open_generic, |
b807c3d0 | 4719 | .read = tracing_read_dyn_info, |
b444786f | 4720 | .llseek = generic_file_llseek, |
bc0c38d1 SR |
4721 | }; |
4722 | #endif | |
4723 | ||
2b6080f2 | 4724 | struct dentry *tracing_init_dentry_tr(struct trace_array *tr) |
bc0c38d1 SR |
4725 | { |
4726 | static int once; | |
4727 | ||
2b6080f2 SR |
4728 | if (tr->dir) |
4729 | return tr->dir; | |
bc0c38d1 | 4730 | |
3e1f60b8 FW |
4731 | if (!debugfs_initialized()) |
4732 | return NULL; | |
4733 | ||
2b6080f2 SR |
4734 | if (tr->flags & TRACE_ARRAY_FL_GLOBAL) |
4735 | tr->dir = debugfs_create_dir("tracing", NULL); | |
bc0c38d1 | 4736 | |
2b6080f2 | 4737 | if (!tr->dir && !once) { |
bc0c38d1 SR |
4738 | once = 1; |
4739 | pr_warning("Could not create debugfs directory 'tracing'\n"); | |
4740 | return NULL; | |
4741 | } | |
4742 | ||
2b6080f2 | 4743 | return tr->dir; |
bc0c38d1 SR |
4744 | } |
4745 | ||
2b6080f2 SR |
4746 | struct dentry *tracing_init_dentry(void) |
4747 | { | |
4748 | return tracing_init_dentry_tr(&global_trace); | |
4749 | } | |
b04cc6b1 | 4750 | |
2b6080f2 | 4751 | static struct dentry *tracing_dentry_percpu(struct trace_array *tr, int cpu) |
b04cc6b1 | 4752 | { |
b04cc6b1 FW |
4753 | struct dentry *d_tracer; |
4754 | ||
2b6080f2 SR |
4755 | if (tr->percpu_dir) |
4756 | return tr->percpu_dir; | |
b04cc6b1 | 4757 | |
2b6080f2 | 4758 | d_tracer = tracing_init_dentry_tr(tr); |
b04cc6b1 FW |
4759 | if (!d_tracer) |
4760 | return NULL; | |
4761 | ||
2b6080f2 | 4762 | tr->percpu_dir = debugfs_create_dir("per_cpu", d_tracer); |
b04cc6b1 | 4763 | |
2b6080f2 SR |
4764 | WARN_ONCE(!tr->percpu_dir, |
4765 | "Could not create debugfs directory 'per_cpu/%d'\n", cpu); | |
b04cc6b1 | 4766 | |
2b6080f2 | 4767 | return tr->percpu_dir; |
b04cc6b1 FW |
4768 | } |
4769 | ||
2b6080f2 SR |
4770 | static void |
4771 | tracing_init_debugfs_percpu(struct trace_array *tr, long cpu) | |
b04cc6b1 | 4772 | { |
a7603ff4 | 4773 | struct trace_array_cpu *data = per_cpu_ptr(tr->data, cpu); |
2b6080f2 | 4774 | struct dentry *d_percpu = tracing_dentry_percpu(tr, cpu); |
5452af66 | 4775 | struct dentry *d_cpu; |
dd49a38c | 4776 | char cpu_dir[30]; /* 30 characters should be more than enough */ |
b04cc6b1 | 4777 | |
0a3d7ce7 NK |
4778 | if (!d_percpu) |
4779 | return; | |
4780 | ||
dd49a38c | 4781 | snprintf(cpu_dir, 30, "cpu%ld", cpu); |
8656e7a2 FW |
4782 | d_cpu = debugfs_create_dir(cpu_dir, d_percpu); |
4783 | if (!d_cpu) { | |
4784 | pr_warning("Could not create debugfs '%s' entry\n", cpu_dir); | |
4785 | return; | |
4786 | } | |
b04cc6b1 | 4787 | |
8656e7a2 | 4788 | /* per cpu trace_pipe */ |
5452af66 | 4789 | trace_create_file("trace_pipe", 0444, d_cpu, |
2b6080f2 | 4790 | (void *)&data->trace_cpu, &tracing_pipe_fops); |
b04cc6b1 FW |
4791 | |
4792 | /* per cpu trace */ | |
5452af66 | 4793 | trace_create_file("trace", 0644, d_cpu, |
2b6080f2 | 4794 | (void *)&data->trace_cpu, &tracing_fops); |
7f96f93f | 4795 | |
5452af66 | 4796 | trace_create_file("trace_pipe_raw", 0444, d_cpu, |
2b6080f2 | 4797 | (void *)&data->trace_cpu, &tracing_buffers_fops); |
7f96f93f | 4798 | |
c8d77183 | 4799 | trace_create_file("stats", 0444, d_cpu, |
2b6080f2 | 4800 | (void *)&data->trace_cpu, &tracing_stats_fops); |
438ced17 VN |
4801 | |
4802 | trace_create_file("buffer_size_kb", 0444, d_cpu, | |
2b6080f2 | 4803 | (void *)&data->trace_cpu, &tracing_entries_fops); |
b04cc6b1 FW |
4804 | } |
4805 | ||
60a11774 SR |
4806 | #ifdef CONFIG_FTRACE_SELFTEST |
4807 | /* Let selftest have access to static functions in this file */ | |
4808 | #include "trace_selftest.c" | |
4809 | #endif | |
4810 | ||
577b785f SR |
4811 | struct trace_option_dentry { |
4812 | struct tracer_opt *opt; | |
4813 | struct tracer_flags *flags; | |
2b6080f2 | 4814 | struct trace_array *tr; |
577b785f SR |
4815 | struct dentry *entry; |
4816 | }; | |
4817 | ||
4818 | static ssize_t | |
4819 | trace_options_read(struct file *filp, char __user *ubuf, size_t cnt, | |
4820 | loff_t *ppos) | |
4821 | { | |
4822 | struct trace_option_dentry *topt = filp->private_data; | |
4823 | char *buf; | |
4824 | ||
4825 | if (topt->flags->val & topt->opt->bit) | |
4826 | buf = "1\n"; | |
4827 | else | |
4828 | buf = "0\n"; | |
4829 | ||
4830 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, 2); | |
4831 | } | |
4832 | ||
4833 | static ssize_t | |
4834 | trace_options_write(struct file *filp, const char __user *ubuf, size_t cnt, | |
4835 | loff_t *ppos) | |
4836 | { | |
4837 | struct trace_option_dentry *topt = filp->private_data; | |
4838 | unsigned long val; | |
577b785f SR |
4839 | int ret; |
4840 | ||
22fe9b54 PH |
4841 | ret = kstrtoul_from_user(ubuf, cnt, 10, &val); |
4842 | if (ret) | |
577b785f SR |
4843 | return ret; |
4844 | ||
8d18eaaf LZ |
4845 | if (val != 0 && val != 1) |
4846 | return -EINVAL; | |
577b785f | 4847 | |
8d18eaaf | 4848 | if (!!(topt->flags->val & topt->opt->bit) != val) { |
577b785f | 4849 | mutex_lock(&trace_types_lock); |
2b6080f2 | 4850 | ret = __set_tracer_option(topt->tr->current_trace, topt->flags, |
c757bea9 | 4851 | topt->opt, !val); |
577b785f SR |
4852 | mutex_unlock(&trace_types_lock); |
4853 | if (ret) | |
4854 | return ret; | |
577b785f SR |
4855 | } |
4856 | ||
4857 | *ppos += cnt; | |
4858 | ||
4859 | return cnt; | |
4860 | } | |
4861 | ||
4862 | ||
4863 | static const struct file_operations trace_options_fops = { | |
4864 | .open = tracing_open_generic, | |
4865 | .read = trace_options_read, | |
4866 | .write = trace_options_write, | |
b444786f | 4867 | .llseek = generic_file_llseek, |
577b785f SR |
4868 | }; |
4869 | ||
a8259075 SR |
4870 | static ssize_t |
4871 | trace_options_core_read(struct file *filp, char __user *ubuf, size_t cnt, | |
4872 | loff_t *ppos) | |
4873 | { | |
4874 | long index = (long)filp->private_data; | |
4875 | char *buf; | |
4876 | ||
4877 | if (trace_flags & (1 << index)) | |
4878 | buf = "1\n"; | |
4879 | else | |
4880 | buf = "0\n"; | |
4881 | ||
4882 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, 2); | |
4883 | } | |
4884 | ||
4885 | static ssize_t | |
4886 | trace_options_core_write(struct file *filp, const char __user *ubuf, size_t cnt, | |
4887 | loff_t *ppos) | |
4888 | { | |
2b6080f2 | 4889 | struct trace_array *tr = &global_trace; |
a8259075 | 4890 | long index = (long)filp->private_data; |
a8259075 SR |
4891 | unsigned long val; |
4892 | int ret; | |
4893 | ||
22fe9b54 PH |
4894 | ret = kstrtoul_from_user(ubuf, cnt, 10, &val); |
4895 | if (ret) | |
a8259075 SR |
4896 | return ret; |
4897 | ||
f2d84b65 | 4898 | if (val != 0 && val != 1) |
a8259075 | 4899 | return -EINVAL; |
69d34da2 SRRH |
4900 | |
4901 | mutex_lock(&trace_types_lock); | |
2b6080f2 | 4902 | ret = set_tracer_flag(tr, 1 << index, val); |
69d34da2 | 4903 | mutex_unlock(&trace_types_lock); |
a8259075 | 4904 | |
613f04a0 SRRH |
4905 | if (ret < 0) |
4906 | return ret; | |
4907 | ||
a8259075 SR |
4908 | *ppos += cnt; |
4909 | ||
4910 | return cnt; | |
4911 | } | |
4912 | ||
a8259075 SR |
4913 | static const struct file_operations trace_options_core_fops = { |
4914 | .open = tracing_open_generic, | |
4915 | .read = trace_options_core_read, | |
4916 | .write = trace_options_core_write, | |
b444786f | 4917 | .llseek = generic_file_llseek, |
a8259075 SR |
4918 | }; |
4919 | ||
5452af66 | 4920 | struct dentry *trace_create_file(const char *name, |
f4ae40a6 | 4921 | umode_t mode, |
5452af66 FW |
4922 | struct dentry *parent, |
4923 | void *data, | |
4924 | const struct file_operations *fops) | |
4925 | { | |
4926 | struct dentry *ret; | |
4927 | ||
4928 | ret = debugfs_create_file(name, mode, parent, data, fops); | |
4929 | if (!ret) | |
4930 | pr_warning("Could not create debugfs '%s' entry\n", name); | |
4931 | ||
4932 | return ret; | |
4933 | } | |
4934 | ||
4935 | ||
2b6080f2 | 4936 | static struct dentry *trace_options_init_dentry(struct trace_array *tr) |
a8259075 SR |
4937 | { |
4938 | struct dentry *d_tracer; | |
a8259075 | 4939 | |
2b6080f2 SR |
4940 | if (tr->options) |
4941 | return tr->options; | |
a8259075 | 4942 | |
2b6080f2 | 4943 | d_tracer = tracing_init_dentry_tr(tr); |
a8259075 SR |
4944 | if (!d_tracer) |
4945 | return NULL; | |
4946 | ||
2b6080f2 SR |
4947 | tr->options = debugfs_create_dir("options", d_tracer); |
4948 | if (!tr->options) { | |
a8259075 SR |
4949 | pr_warning("Could not create debugfs directory 'options'\n"); |
4950 | return NULL; | |
4951 | } | |
4952 | ||
2b6080f2 | 4953 | return tr->options; |
a8259075 SR |
4954 | } |
4955 | ||
577b785f | 4956 | static void |
2b6080f2 SR |
4957 | create_trace_option_file(struct trace_array *tr, |
4958 | struct trace_option_dentry *topt, | |
577b785f SR |
4959 | struct tracer_flags *flags, |
4960 | struct tracer_opt *opt) | |
4961 | { | |
4962 | struct dentry *t_options; | |
577b785f | 4963 | |
2b6080f2 | 4964 | t_options = trace_options_init_dentry(tr); |
577b785f SR |
4965 | if (!t_options) |
4966 | return; | |
4967 | ||
4968 | topt->flags = flags; | |
4969 | topt->opt = opt; | |
2b6080f2 | 4970 | topt->tr = tr; |
577b785f | 4971 | |
5452af66 | 4972 | topt->entry = trace_create_file(opt->name, 0644, t_options, topt, |
577b785f SR |
4973 | &trace_options_fops); |
4974 | ||
577b785f SR |
4975 | } |
4976 | ||
4977 | static struct trace_option_dentry * | |
2b6080f2 | 4978 | create_trace_option_files(struct trace_array *tr, struct tracer *tracer) |
577b785f SR |
4979 | { |
4980 | struct trace_option_dentry *topts; | |
4981 | struct tracer_flags *flags; | |
4982 | struct tracer_opt *opts; | |
4983 | int cnt; | |
4984 | ||
4985 | if (!tracer) | |
4986 | return NULL; | |
4987 | ||
4988 | flags = tracer->flags; | |
4989 | ||
4990 | if (!flags || !flags->opts) | |
4991 | return NULL; | |
4992 | ||
4993 | opts = flags->opts; | |
4994 | ||
4995 | for (cnt = 0; opts[cnt].name; cnt++) | |
4996 | ; | |
4997 | ||
0cfe8245 | 4998 | topts = kcalloc(cnt + 1, sizeof(*topts), GFP_KERNEL); |
577b785f SR |
4999 | if (!topts) |
5000 | return NULL; | |
5001 | ||
5002 | for (cnt = 0; opts[cnt].name; cnt++) | |
2b6080f2 | 5003 | create_trace_option_file(tr, &topts[cnt], flags, |
577b785f SR |
5004 | &opts[cnt]); |
5005 | ||
5006 | return topts; | |
5007 | } | |
5008 | ||
5009 | static void | |
5010 | destroy_trace_option_files(struct trace_option_dentry *topts) | |
5011 | { | |
5012 | int cnt; | |
5013 | ||
5014 | if (!topts) | |
5015 | return; | |
5016 | ||
5017 | for (cnt = 0; topts[cnt].opt; cnt++) { | |
5018 | if (topts[cnt].entry) | |
5019 | debugfs_remove(topts[cnt].entry); | |
5020 | } | |
5021 | ||
5022 | kfree(topts); | |
5023 | } | |
5024 | ||
a8259075 | 5025 | static struct dentry * |
2b6080f2 SR |
5026 | create_trace_option_core_file(struct trace_array *tr, |
5027 | const char *option, long index) | |
a8259075 SR |
5028 | { |
5029 | struct dentry *t_options; | |
a8259075 | 5030 | |
2b6080f2 | 5031 | t_options = trace_options_init_dentry(tr); |
a8259075 SR |
5032 | if (!t_options) |
5033 | return NULL; | |
5034 | ||
5452af66 | 5035 | return trace_create_file(option, 0644, t_options, (void *)index, |
a8259075 | 5036 | &trace_options_core_fops); |
a8259075 SR |
5037 | } |
5038 | ||
2b6080f2 | 5039 | static __init void create_trace_options_dir(struct trace_array *tr) |
a8259075 SR |
5040 | { |
5041 | struct dentry *t_options; | |
a8259075 SR |
5042 | int i; |
5043 | ||
2b6080f2 | 5044 | t_options = trace_options_init_dentry(tr); |
a8259075 SR |
5045 | if (!t_options) |
5046 | return; | |
5047 | ||
5452af66 | 5048 | for (i = 0; trace_options[i]; i++) |
2b6080f2 | 5049 | create_trace_option_core_file(tr, trace_options[i], i); |
a8259075 SR |
5050 | } |
5051 | ||
499e5470 SR |
5052 | static ssize_t |
5053 | rb_simple_read(struct file *filp, char __user *ubuf, | |
5054 | size_t cnt, loff_t *ppos) | |
5055 | { | |
348f0fc2 SR |
5056 | struct trace_array *tr = filp->private_data; |
5057 | struct ring_buffer *buffer = tr->buffer; | |
499e5470 SR |
5058 | char buf[64]; |
5059 | int r; | |
5060 | ||
5061 | if (buffer) | |
5062 | r = ring_buffer_record_is_on(buffer); | |
5063 | else | |
5064 | r = 0; | |
5065 | ||
5066 | r = sprintf(buf, "%d\n", r); | |
5067 | ||
5068 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, r); | |
5069 | } | |
5070 | ||
5071 | static ssize_t | |
5072 | rb_simple_write(struct file *filp, const char __user *ubuf, | |
5073 | size_t cnt, loff_t *ppos) | |
5074 | { | |
348f0fc2 SR |
5075 | struct trace_array *tr = filp->private_data; |
5076 | struct ring_buffer *buffer = tr->buffer; | |
499e5470 SR |
5077 | unsigned long val; |
5078 | int ret; | |
5079 | ||
5080 | ret = kstrtoul_from_user(ubuf, cnt, 10, &val); | |
5081 | if (ret) | |
5082 | return ret; | |
5083 | ||
5084 | if (buffer) { | |
2df8f8a6 SR |
5085 | mutex_lock(&trace_types_lock); |
5086 | if (val) { | |
499e5470 | 5087 | ring_buffer_record_on(buffer); |
2b6080f2 SR |
5088 | if (tr->current_trace->start) |
5089 | tr->current_trace->start(tr); | |
2df8f8a6 | 5090 | } else { |
499e5470 | 5091 | ring_buffer_record_off(buffer); |
2b6080f2 SR |
5092 | if (tr->current_trace->stop) |
5093 | tr->current_trace->stop(tr); | |
2df8f8a6 SR |
5094 | } |
5095 | mutex_unlock(&trace_types_lock); | |
499e5470 SR |
5096 | } |
5097 | ||
5098 | (*ppos)++; | |
5099 | ||
5100 | return cnt; | |
5101 | } | |
5102 | ||
5103 | static const struct file_operations rb_simple_fops = { | |
5104 | .open = tracing_open_generic, | |
5105 | .read = rb_simple_read, | |
5106 | .write = rb_simple_write, | |
5107 | .llseek = default_llseek, | |
5108 | }; | |
5109 | ||
2b6080f2 SR |
5110 | static void |
5111 | init_tracer_debugfs(struct trace_array *tr, struct dentry *d_tracer) | |
5112 | { | |
5113 | ||
5114 | trace_create_file("trace_options", 0644, d_tracer, | |
5115 | tr, &tracing_iter_fops); | |
5116 | ||
5117 | trace_create_file("trace", 0644, d_tracer, | |
5118 | (void *)&tr->trace_cpu, &tracing_fops); | |
5119 | ||
5120 | trace_create_file("trace_pipe", 0444, d_tracer, | |
5121 | (void *)&tr->trace_cpu, &tracing_pipe_fops); | |
5122 | ||
5123 | trace_create_file("buffer_size_kb", 0644, d_tracer, | |
5124 | (void *)&tr->trace_cpu, &tracing_entries_fops); | |
5125 | ||
5126 | trace_create_file("buffer_total_size_kb", 0444, d_tracer, | |
5127 | tr, &tracing_total_entries_fops); | |
5128 | ||
5129 | trace_create_file("free_buffer", 0644, d_tracer, | |
5130 | tr, &tracing_free_buffer_fops); | |
5131 | ||
5132 | trace_create_file("trace_marker", 0220, d_tracer, | |
5133 | tr, &tracing_mark_fops); | |
5134 | ||
5135 | trace_create_file("trace_clock", 0644, d_tracer, tr, | |
5136 | &trace_clock_fops); | |
5137 | ||
5138 | trace_create_file("tracing_on", 0644, d_tracer, | |
5139 | tr, &rb_simple_fops); | |
5140 | } | |
5141 | ||
b5ad384e | 5142 | static __init int tracer_init_debugfs(void) |
bc0c38d1 SR |
5143 | { |
5144 | struct dentry *d_tracer; | |
b04cc6b1 | 5145 | int cpu; |
bc0c38d1 | 5146 | |
7e53bd42 LJ |
5147 | trace_access_lock_init(); |
5148 | ||
bc0c38d1 SR |
5149 | d_tracer = tracing_init_dentry(); |
5150 | ||
2b6080f2 | 5151 | init_tracer_debugfs(&global_trace, d_tracer); |
bc0c38d1 | 5152 | |
5452af66 | 5153 | trace_create_file("tracing_cpumask", 0644, d_tracer, |
2b6080f2 | 5154 | &global_trace, &tracing_cpumask_fops); |
a8259075 | 5155 | |
5452af66 FW |
5156 | trace_create_file("available_tracers", 0444, d_tracer, |
5157 | &global_trace, &show_traces_fops); | |
5158 | ||
339ae5d3 | 5159 | trace_create_file("current_tracer", 0644, d_tracer, |
5452af66 FW |
5160 | &global_trace, &set_tracer_fops); |
5161 | ||
5d4a9dba | 5162 | #ifdef CONFIG_TRACER_MAX_TRACE |
5452af66 FW |
5163 | trace_create_file("tracing_max_latency", 0644, d_tracer, |
5164 | &tracing_max_latency, &tracing_max_lat_fops); | |
0e950173 | 5165 | #endif |
5452af66 FW |
5166 | |
5167 | trace_create_file("tracing_thresh", 0644, d_tracer, | |
5168 | &tracing_thresh, &tracing_max_lat_fops); | |
a8259075 | 5169 | |
339ae5d3 | 5170 | trace_create_file("README", 0444, d_tracer, |
5452af66 FW |
5171 | NULL, &tracing_readme_fops); |
5172 | ||
69abe6a5 AP |
5173 | trace_create_file("saved_cmdlines", 0444, d_tracer, |
5174 | NULL, &tracing_saved_cmdlines_fops); | |
5bf9a1ee | 5175 | |
bc0c38d1 | 5176 | #ifdef CONFIG_DYNAMIC_FTRACE |
5452af66 FW |
5177 | trace_create_file("dyn_ftrace_total_info", 0444, d_tracer, |
5178 | &ftrace_update_tot_cnt, &tracing_dyn_info_fops); | |
bc0c38d1 | 5179 | #endif |
b04cc6b1 | 5180 | |
debdd57f HT |
5181 | #ifdef CONFIG_TRACER_SNAPSHOT |
5182 | trace_create_file("snapshot", 0644, d_tracer, | |
2b6080f2 | 5183 | (void *)&global_trace.trace_cpu, &snapshot_fops); |
debdd57f HT |
5184 | #endif |
5185 | ||
2b6080f2 | 5186 | create_trace_options_dir(&global_trace); |
5452af66 | 5187 | |
b04cc6b1 | 5188 | for_each_tracing_cpu(cpu) |
2b6080f2 | 5189 | tracing_init_debugfs_percpu(&global_trace, cpu); |
b04cc6b1 | 5190 | |
b5ad384e | 5191 | return 0; |
bc0c38d1 SR |
5192 | } |
5193 | ||
3f5a54e3 SR |
5194 | static int trace_panic_handler(struct notifier_block *this, |
5195 | unsigned long event, void *unused) | |
5196 | { | |
944ac425 | 5197 | if (ftrace_dump_on_oops) |
cecbca96 | 5198 | ftrace_dump(ftrace_dump_on_oops); |
3f5a54e3 SR |
5199 | return NOTIFY_OK; |
5200 | } | |
5201 | ||
5202 | static struct notifier_block trace_panic_notifier = { | |
5203 | .notifier_call = trace_panic_handler, | |
5204 | .next = NULL, | |
5205 | .priority = 150 /* priority: INT_MAX >= x >= 0 */ | |
5206 | }; | |
5207 | ||
5208 | static int trace_die_handler(struct notifier_block *self, | |
5209 | unsigned long val, | |
5210 | void *data) | |
5211 | { | |
5212 | switch (val) { | |
5213 | case DIE_OOPS: | |
944ac425 | 5214 | if (ftrace_dump_on_oops) |
cecbca96 | 5215 | ftrace_dump(ftrace_dump_on_oops); |
3f5a54e3 SR |
5216 | break; |
5217 | default: | |
5218 | break; | |
5219 | } | |
5220 | return NOTIFY_OK; | |
5221 | } | |
5222 | ||
5223 | static struct notifier_block trace_die_notifier = { | |
5224 | .notifier_call = trace_die_handler, | |
5225 | .priority = 200 | |
5226 | }; | |
5227 | ||
5228 | /* | |
5229 | * printk is set to max of 1024, we really don't need it that big. | |
5230 | * Nothing should be printing 1000 characters anyway. | |
5231 | */ | |
5232 | #define TRACE_MAX_PRINT 1000 | |
5233 | ||
5234 | /* | |
5235 | * Define here KERN_TRACE so that we have one place to modify | |
5236 | * it if we decide to change what log level the ftrace dump | |
5237 | * should be at. | |
5238 | */ | |
428aee14 | 5239 | #define KERN_TRACE KERN_EMERG |
3f5a54e3 | 5240 | |
955b61e5 | 5241 | void |
3f5a54e3 SR |
5242 | trace_printk_seq(struct trace_seq *s) |
5243 | { | |
5244 | /* Probably should print a warning here. */ | |
5245 | if (s->len >= 1000) | |
5246 | s->len = 1000; | |
5247 | ||
5248 | /* should be zero ended, but we are paranoid. */ | |
5249 | s->buffer[s->len] = 0; | |
5250 | ||
5251 | printk(KERN_TRACE "%s", s->buffer); | |
5252 | ||
f9520750 | 5253 | trace_seq_init(s); |
3f5a54e3 SR |
5254 | } |
5255 | ||
955b61e5 JW |
5256 | void trace_init_global_iter(struct trace_iterator *iter) |
5257 | { | |
5258 | iter->tr = &global_trace; | |
2b6080f2 | 5259 | iter->trace = iter->tr->current_trace; |
ae3b5093 | 5260 | iter->cpu_file = RING_BUFFER_ALL_CPUS; |
955b61e5 JW |
5261 | } |
5262 | ||
cecbca96 FW |
5263 | static void |
5264 | __ftrace_dump(bool disable_tracing, enum ftrace_dump_mode oops_dump_mode) | |
3f5a54e3 | 5265 | { |
445c8951 | 5266 | static arch_spinlock_t ftrace_dump_lock = |
edc35bd7 | 5267 | (arch_spinlock_t)__ARCH_SPIN_LOCK_UNLOCKED; |
3f5a54e3 SR |
5268 | /* use static because iter can be a bit big for the stack */ |
5269 | static struct trace_iterator iter; | |
cf586b61 | 5270 | unsigned int old_userobj; |
3f5a54e3 | 5271 | static int dump_ran; |
d769041f SR |
5272 | unsigned long flags; |
5273 | int cnt = 0, cpu; | |
3f5a54e3 SR |
5274 | |
5275 | /* only one dump */ | |
cd891ae0 | 5276 | local_irq_save(flags); |
0199c4e6 | 5277 | arch_spin_lock(&ftrace_dump_lock); |
3f5a54e3 SR |
5278 | if (dump_ran) |
5279 | goto out; | |
5280 | ||
5281 | dump_ran = 1; | |
5282 | ||
0ee6b6cf | 5283 | tracing_off(); |
cf586b61 | 5284 | |
e0a413f6 SR |
5285 | /* Did function tracer already get disabled? */ |
5286 | if (ftrace_is_dead()) { | |
5287 | printk("# WARNING: FUNCTION TRACING IS CORRUPTED\n"); | |
5288 | printk("# MAY BE MISSING FUNCTION EVENTS\n"); | |
5289 | } | |
5290 | ||
cf586b61 FW |
5291 | if (disable_tracing) |
5292 | ftrace_kill(); | |
3f5a54e3 | 5293 | |
38dbe0b1 | 5294 | /* Simulate the iterator */ |
955b61e5 JW |
5295 | trace_init_global_iter(&iter); |
5296 | ||
d769041f | 5297 | for_each_tracing_cpu(cpu) { |
a7603ff4 | 5298 | atomic_inc(&per_cpu_ptr(iter.tr->data, cpu)->disabled); |
d769041f SR |
5299 | } |
5300 | ||
cf586b61 FW |
5301 | old_userobj = trace_flags & TRACE_ITER_SYM_USEROBJ; |
5302 | ||
b54d3de9 TE |
5303 | /* don't look at user memory in panic mode */ |
5304 | trace_flags &= ~TRACE_ITER_SYM_USEROBJ; | |
5305 | ||
cecbca96 FW |
5306 | switch (oops_dump_mode) { |
5307 | case DUMP_ALL: | |
ae3b5093 | 5308 | iter.cpu_file = RING_BUFFER_ALL_CPUS; |
cecbca96 FW |
5309 | break; |
5310 | case DUMP_ORIG: | |
5311 | iter.cpu_file = raw_smp_processor_id(); | |
5312 | break; | |
5313 | case DUMP_NONE: | |
5314 | goto out_enable; | |
5315 | default: | |
5316 | printk(KERN_TRACE "Bad dumping mode, switching to all CPUs dump\n"); | |
ae3b5093 | 5317 | iter.cpu_file = RING_BUFFER_ALL_CPUS; |
cecbca96 FW |
5318 | } |
5319 | ||
5320 | printk(KERN_TRACE "Dumping ftrace buffer:\n"); | |
3f5a54e3 SR |
5321 | |
5322 | /* | |
5323 | * We need to stop all tracing on all CPUS to read the | |
5324 | * the next buffer. This is a bit expensive, but is | |
5325 | * not done often. We fill all what we can read, | |
5326 | * and then release the locks again. | |
5327 | */ | |
5328 | ||
3f5a54e3 SR |
5329 | while (!trace_empty(&iter)) { |
5330 | ||
5331 | if (!cnt) | |
5332 | printk(KERN_TRACE "---------------------------------\n"); | |
5333 | ||
5334 | cnt++; | |
5335 | ||
5336 | /* reset all but tr, trace, and overruns */ | |
5337 | memset(&iter.seq, 0, | |
5338 | sizeof(struct trace_iterator) - | |
5339 | offsetof(struct trace_iterator, seq)); | |
5340 | iter.iter_flags |= TRACE_FILE_LAT_FMT; | |
5341 | iter.pos = -1; | |
5342 | ||
955b61e5 | 5343 | if (trace_find_next_entry_inc(&iter) != NULL) { |
74e7ff8c LJ |
5344 | int ret; |
5345 | ||
5346 | ret = print_trace_line(&iter); | |
5347 | if (ret != TRACE_TYPE_NO_CONSUME) | |
5348 | trace_consume(&iter); | |
3f5a54e3 | 5349 | } |
b892e5c8 | 5350 | touch_nmi_watchdog(); |
3f5a54e3 SR |
5351 | |
5352 | trace_printk_seq(&iter.seq); | |
5353 | } | |
5354 | ||
5355 | if (!cnt) | |
5356 | printk(KERN_TRACE " (ftrace buffer empty)\n"); | |
5357 | else | |
5358 | printk(KERN_TRACE "---------------------------------\n"); | |
5359 | ||
cecbca96 | 5360 | out_enable: |
cf586b61 FW |
5361 | /* Re-enable tracing if requested */ |
5362 | if (!disable_tracing) { | |
5363 | trace_flags |= old_userobj; | |
5364 | ||
5365 | for_each_tracing_cpu(cpu) { | |
a7603ff4 | 5366 | atomic_dec(&per_cpu_ptr(iter.tr->data, cpu)->disabled); |
cf586b61 FW |
5367 | } |
5368 | tracing_on(); | |
5369 | } | |
5370 | ||
3f5a54e3 | 5371 | out: |
0199c4e6 | 5372 | arch_spin_unlock(&ftrace_dump_lock); |
cd891ae0 | 5373 | local_irq_restore(flags); |
3f5a54e3 SR |
5374 | } |
5375 | ||
cf586b61 | 5376 | /* By default: disable tracing after the dump */ |
cecbca96 | 5377 | void ftrace_dump(enum ftrace_dump_mode oops_dump_mode) |
cf586b61 | 5378 | { |
cecbca96 | 5379 | __ftrace_dump(true, oops_dump_mode); |
cf586b61 | 5380 | } |
a8eecf22 | 5381 | EXPORT_SYMBOL_GPL(ftrace_dump); |
cf586b61 | 5382 | |
3928a8a2 | 5383 | __init static int tracer_alloc_buffers(void) |
bc0c38d1 | 5384 | { |
73c5162a | 5385 | int ring_buf_size; |
750912fa | 5386 | enum ring_buffer_flags rb_flags; |
4c11d7ae | 5387 | int i; |
9e01c1b7 | 5388 | int ret = -ENOMEM; |
4c11d7ae | 5389 | |
750912fa | 5390 | |
9e01c1b7 RR |
5391 | if (!alloc_cpumask_var(&tracing_buffer_mask, GFP_KERNEL)) |
5392 | goto out; | |
5393 | ||
5394 | if (!alloc_cpumask_var(&tracing_cpumask, GFP_KERNEL)) | |
5395 | goto out_free_buffer_mask; | |
4c11d7ae | 5396 | |
07d777fe SR |
5397 | /* Only allocate trace_printk buffers if a trace_printk exists */ |
5398 | if (__stop___trace_bprintk_fmt != __start___trace_bprintk_fmt) | |
81698831 | 5399 | /* Must be called before global_trace.buffer is allocated */ |
07d777fe SR |
5400 | trace_printk_init_buffers(); |
5401 | ||
73c5162a SR |
5402 | /* To save memory, keep the ring buffer size to its minimum */ |
5403 | if (ring_buffer_expanded) | |
5404 | ring_buf_size = trace_buf_size; | |
5405 | else | |
5406 | ring_buf_size = 1; | |
5407 | ||
750912fa DS |
5408 | rb_flags = trace_flags & TRACE_ITER_OVERWRITE ? RB_FL_OVERWRITE : 0; |
5409 | ||
9e01c1b7 RR |
5410 | cpumask_copy(tracing_buffer_mask, cpu_possible_mask); |
5411 | cpumask_copy(tracing_cpumask, cpu_all_mask); | |
5412 | ||
2b6080f2 SR |
5413 | raw_spin_lock_init(&global_trace.start_lock); |
5414 | ||
9e01c1b7 | 5415 | /* TODO: make the number of buffers hot pluggable with CPUS */ |
750912fa | 5416 | global_trace.buffer = ring_buffer_alloc(ring_buf_size, rb_flags); |
3928a8a2 SR |
5417 | if (!global_trace.buffer) { |
5418 | printk(KERN_ERR "tracer: failed to allocate ring buffer!\n"); | |
5419 | WARN_ON(1); | |
9e01c1b7 | 5420 | goto out_free_cpumask; |
4c11d7ae | 5421 | } |
a7603ff4 SR |
5422 | |
5423 | global_trace.data = alloc_percpu(struct trace_array_cpu); | |
5424 | ||
5425 | if (!global_trace.data) { | |
5426 | printk(KERN_ERR "tracer: failed to allocate percpu memory!\n"); | |
5427 | WARN_ON(1); | |
5428 | goto out_free_cpumask; | |
5429 | } | |
5430 | ||
5431 | for_each_tracing_cpu(i) { | |
5432 | memset(per_cpu_ptr(global_trace.data, i), 0, sizeof(struct trace_array_cpu)); | |
5433 | per_cpu_ptr(global_trace.data, i)->trace_cpu.cpu = i; | |
5434 | per_cpu_ptr(global_trace.data, i)->trace_cpu.tr = &global_trace; | |
5435 | } | |
5436 | ||
499e5470 SR |
5437 | if (global_trace.buffer_disabled) |
5438 | tracing_off(); | |
4c11d7ae SR |
5439 | |
5440 | #ifdef CONFIG_TRACER_MAX_TRACE | |
a7603ff4 SR |
5441 | max_tr.data = alloc_percpu(struct trace_array_cpu); |
5442 | if (!max_tr.data) { | |
5443 | printk(KERN_ERR "tracer: failed to allocate percpu memory!\n"); | |
5444 | WARN_ON(1); | |
5445 | goto out_free_cpumask; | |
5446 | } | |
750912fa | 5447 | max_tr.buffer = ring_buffer_alloc(1, rb_flags); |
2b6080f2 | 5448 | raw_spin_lock_init(&max_tr.start_lock); |
3928a8a2 SR |
5449 | if (!max_tr.buffer) { |
5450 | printk(KERN_ERR "tracer: failed to allocate max ring buffer!\n"); | |
5451 | WARN_ON(1); | |
5452 | ring_buffer_free(global_trace.buffer); | |
9e01c1b7 | 5453 | goto out_free_cpumask; |
4c11d7ae | 5454 | } |
ab46428c | 5455 | |
ab46428c | 5456 | for_each_tracing_cpu(i) { |
a7603ff4 SR |
5457 | memset(per_cpu_ptr(max_tr.data, i), 0, sizeof(struct trace_array_cpu)); |
5458 | per_cpu_ptr(max_tr.data, i)->trace_cpu.cpu = i; | |
5459 | per_cpu_ptr(max_tr.data, i)->trace_cpu.tr = &max_tr; | |
4c11d7ae | 5460 | } |
a7603ff4 | 5461 | #endif |
438ced17 | 5462 | |
a7603ff4 | 5463 | /* Allocate the first page for all buffers */ |
a591c73f VN |
5464 | set_buffer_entries(&global_trace, |
5465 | ring_buffer_size(global_trace.buffer, 0)); | |
438ced17 VN |
5466 | #ifdef CONFIG_TRACER_MAX_TRACE |
5467 | set_buffer_entries(&max_tr, 1); | |
5468 | #endif | |
bc0c38d1 | 5469 | |
bc0c38d1 | 5470 | trace_init_cmdlines(); |
0d5c6e1c | 5471 | init_irq_work(&trace_work_wakeup, trace_wake_up); |
bc0c38d1 | 5472 | |
43a15386 | 5473 | register_tracer(&nop_trace); |
d840f718 | 5474 | |
2b6080f2 SR |
5475 | global_trace.current_trace = &nop_trace; |
5476 | ||
60a11774 SR |
5477 | /* All seems OK, enable tracing */ |
5478 | tracing_disabled = 0; | |
3928a8a2 | 5479 | |
3f5a54e3 SR |
5480 | atomic_notifier_chain_register(&panic_notifier_list, |
5481 | &trace_panic_notifier); | |
5482 | ||
5483 | register_die_notifier(&trace_die_notifier); | |
2fc1dfbe | 5484 | |
ae63b31e SR |
5485 | global_trace.flags = TRACE_ARRAY_FL_GLOBAL; |
5486 | ||
2b6080f2 SR |
5487 | /* Holder for file callbacks */ |
5488 | global_trace.trace_cpu.cpu = RING_BUFFER_ALL_CPUS; | |
5489 | global_trace.trace_cpu.tr = &global_trace; | |
5490 | ||
ae63b31e SR |
5491 | INIT_LIST_HEAD(&global_trace.systems); |
5492 | INIT_LIST_HEAD(&global_trace.events); | |
5493 | list_add(&global_trace.list, &ftrace_trace_arrays); | |
5494 | ||
7bcfaf54 SR |
5495 | while (trace_boot_options) { |
5496 | char *option; | |
5497 | ||
5498 | option = strsep(&trace_boot_options, ","); | |
2b6080f2 | 5499 | trace_set_options(&global_trace, option); |
7bcfaf54 SR |
5500 | } |
5501 | ||
2fc1dfbe | 5502 | return 0; |
3f5a54e3 | 5503 | |
9e01c1b7 | 5504 | out_free_cpumask: |
a7603ff4 SR |
5505 | free_percpu(global_trace.data); |
5506 | free_percpu(max_tr.data); | |
9e01c1b7 RR |
5507 | free_cpumask_var(tracing_cpumask); |
5508 | out_free_buffer_mask: | |
5509 | free_cpumask_var(tracing_buffer_mask); | |
5510 | out: | |
5511 | return ret; | |
bc0c38d1 | 5512 | } |
b2821ae6 SR |
5513 | |
5514 | __init static int clear_boot_tracer(void) | |
5515 | { | |
5516 | /* | |
5517 | * The default tracer at boot buffer is an init section. | |
5518 | * This function is called in lateinit. If we did not | |
5519 | * find the boot tracer, then clear it out, to prevent | |
5520 | * later registration from accessing the buffer that is | |
5521 | * about to be freed. | |
5522 | */ | |
5523 | if (!default_bootup_tracer) | |
5524 | return 0; | |
5525 | ||
5526 | printk(KERN_INFO "ftrace bootup tracer '%s' not registered.\n", | |
5527 | default_bootup_tracer); | |
5528 | default_bootup_tracer = NULL; | |
5529 | ||
5530 | return 0; | |
5531 | } | |
5532 | ||
b5ad384e FW |
5533 | early_initcall(tracer_alloc_buffers); |
5534 | fs_initcall(tracer_init_debugfs); | |
b2821ae6 | 5535 | late_initcall(clear_boot_tracer); |