]>
Commit | Line | Data |
---|---|---|
d01f4e8d NK |
1 | /* |
2 | * builtin-ftrace.c | |
3 | * | |
4 | * Copyright (c) 2013 LG Electronics, Namhyung Kim <namhyung@kernel.org> | |
5 | * | |
6 | * Released under the GPL v2. | |
7 | */ | |
8 | ||
9 | #include "builtin.h" | |
10 | #include "perf.h" | |
11 | ||
a43783ae | 12 | #include <errno.h> |
d01f4e8d NK |
13 | #include <unistd.h> |
14 | #include <signal.h> | |
a9af6be5 | 15 | #include <fcntl.h> |
4208735d | 16 | #include <poll.h> |
d01f4e8d NK |
17 | |
18 | #include "debug.h" | |
19 | #include <subcmd/parse-options.h> | |
20a9ed28 | 20 | #include <api/fs/tracing_path.h> |
d01f4e8d NK |
21 | #include "evlist.h" |
22 | #include "target.h" | |
dc231032 | 23 | #include "cpumap.h" |
d01f4e8d | 24 | #include "thread_map.h" |
b05d1093 | 25 | #include "util/config.h" |
d01f4e8d NK |
26 | |
27 | ||
28 | #define DEFAULT_TRACER "function_graph" | |
29 | ||
30 | struct perf_ftrace { | |
78b83e8b NK |
31 | struct perf_evlist *evlist; |
32 | struct target target; | |
33 | const char *tracer; | |
34 | struct list_head filters; | |
35 | struct list_head notrace; | |
36 | struct list_head graph_funcs; | |
37 | struct list_head nograph_funcs; | |
1096c35a | 38 | int graph_depth; |
78b83e8b NK |
39 | }; |
40 | ||
41 | struct filter_entry { | |
42 | struct list_head list; | |
43 | char name[]; | |
d01f4e8d NK |
44 | }; |
45 | ||
46 | static bool done; | |
47 | ||
48 | static void sig_handler(int sig __maybe_unused) | |
49 | { | |
50 | done = true; | |
51 | } | |
52 | ||
53 | /* | |
54 | * perf_evlist__prepare_workload will send a SIGUSR1 if the fork fails, since | |
55 | * we asked by setting its exec_error to the function below, | |
56 | * ftrace__workload_exec_failed_signal. | |
57 | * | |
58 | * XXX We need to handle this more appropriately, emitting an error, etc. | |
59 | */ | |
60 | static void ftrace__workload_exec_failed_signal(int signo __maybe_unused, | |
61 | siginfo_t *info __maybe_unused, | |
62 | void *ucontext __maybe_unused) | |
63 | { | |
64 | /* workload_exec_errno = info->si_value.sival_int; */ | |
65 | done = true; | |
66 | } | |
67 | ||
a9af6be5 | 68 | static int __write_tracing_file(const char *name, const char *val, bool append) |
d01f4e8d NK |
69 | { |
70 | char *file; | |
71 | int fd, ret = -1; | |
72 | ssize_t size = strlen(val); | |
a9af6be5 | 73 | int flags = O_WRONLY; |
e7bd9ba2 | 74 | char errbuf[512]; |
63cd02d8 | 75 | char *val_copy; |
d01f4e8d NK |
76 | |
77 | file = get_tracing_file(name); | |
78 | if (!file) { | |
79 | pr_debug("cannot get tracing file: %s\n", name); | |
80 | return -1; | |
81 | } | |
82 | ||
a9af6be5 NK |
83 | if (append) |
84 | flags |= O_APPEND; | |
85 | else | |
86 | flags |= O_TRUNC; | |
87 | ||
88 | fd = open(file, flags); | |
d01f4e8d | 89 | if (fd < 0) { |
e7bd9ba2 NK |
90 | pr_debug("cannot open tracing file: %s: %s\n", |
91 | name, str_error_r(errno, errbuf, sizeof(errbuf))); | |
d01f4e8d NK |
92 | goto out; |
93 | } | |
94 | ||
63cd02d8 CD |
95 | /* |
96 | * Copy the original value and append a '\n'. Without this, | |
97 | * the kernel can hide possible errors. | |
98 | */ | |
99 | val_copy = strdup(val); | |
100 | if (!val_copy) | |
101 | goto out_close; | |
102 | val_copy[size] = '\n'; | |
103 | ||
104 | if (write(fd, val_copy, size + 1) == size + 1) | |
d01f4e8d NK |
105 | ret = 0; |
106 | else | |
e7bd9ba2 NK |
107 | pr_debug("write '%s' to tracing/%s failed: %s\n", |
108 | val, name, str_error_r(errno, errbuf, sizeof(errbuf))); | |
d01f4e8d | 109 | |
63cd02d8 CD |
110 | free(val_copy); |
111 | out_close: | |
d01f4e8d NK |
112 | close(fd); |
113 | out: | |
114 | put_tracing_file(file); | |
115 | return ret; | |
116 | } | |
117 | ||
a9af6be5 NK |
118 | static int write_tracing_file(const char *name, const char *val) |
119 | { | |
120 | return __write_tracing_file(name, val, false); | |
121 | } | |
122 | ||
123 | static int append_tracing_file(const char *name, const char *val) | |
124 | { | |
125 | return __write_tracing_file(name, val, true); | |
126 | } | |
127 | ||
dc231032 | 128 | static int reset_tracing_cpu(void); |
78b83e8b | 129 | static void reset_tracing_filters(void); |
dc231032 | 130 | |
d01f4e8d NK |
131 | static int reset_tracing_files(struct perf_ftrace *ftrace __maybe_unused) |
132 | { | |
133 | if (write_tracing_file("tracing_on", "0") < 0) | |
134 | return -1; | |
135 | ||
136 | if (write_tracing_file("current_tracer", "nop") < 0) | |
137 | return -1; | |
138 | ||
139 | if (write_tracing_file("set_ftrace_pid", " ") < 0) | |
140 | return -1; | |
141 | ||
dc231032 NK |
142 | if (reset_tracing_cpu() < 0) |
143 | return -1; | |
144 | ||
1096c35a NK |
145 | if (write_tracing_file("max_graph_depth", "0") < 0) |
146 | return -1; | |
147 | ||
78b83e8b | 148 | reset_tracing_filters(); |
d01f4e8d NK |
149 | return 0; |
150 | } | |
151 | ||
a9af6be5 NK |
152 | static int set_tracing_pid(struct perf_ftrace *ftrace) |
153 | { | |
154 | int i; | |
155 | char buf[16]; | |
156 | ||
157 | if (target__has_cpu(&ftrace->target)) | |
158 | return 0; | |
159 | ||
160 | for (i = 0; i < thread_map__nr(ftrace->evlist->threads); i++) { | |
161 | scnprintf(buf, sizeof(buf), "%d", | |
162 | ftrace->evlist->threads->map[i]); | |
163 | if (append_tracing_file("set_ftrace_pid", buf) < 0) | |
164 | return -1; | |
165 | } | |
166 | return 0; | |
167 | } | |
168 | ||
dc231032 NK |
169 | static int set_tracing_cpumask(struct cpu_map *cpumap) |
170 | { | |
171 | char *cpumask; | |
172 | size_t mask_size; | |
173 | int ret; | |
174 | int last_cpu; | |
175 | ||
176 | last_cpu = cpu_map__cpu(cpumap, cpumap->nr - 1); | |
177 | mask_size = (last_cpu + 3) / 4 + 1; | |
178 | mask_size += last_cpu / 32; /* ',' is needed for every 32th cpus */ | |
179 | ||
180 | cpumask = malloc(mask_size); | |
181 | if (cpumask == NULL) { | |
182 | pr_debug("failed to allocate cpu mask\n"); | |
183 | return -1; | |
184 | } | |
185 | ||
186 | cpu_map__snprint_mask(cpumap, cpumask, mask_size); | |
187 | ||
188 | ret = write_tracing_file("tracing_cpumask", cpumask); | |
189 | ||
190 | free(cpumask); | |
191 | return ret; | |
192 | } | |
193 | ||
194 | static int set_tracing_cpu(struct perf_ftrace *ftrace) | |
195 | { | |
196 | struct cpu_map *cpumap = ftrace->evlist->cpus; | |
197 | ||
198 | if (!target__has_cpu(&ftrace->target)) | |
199 | return 0; | |
200 | ||
201 | return set_tracing_cpumask(cpumap); | |
202 | } | |
203 | ||
204 | static int reset_tracing_cpu(void) | |
205 | { | |
206 | struct cpu_map *cpumap = cpu_map__new(NULL); | |
207 | int ret; | |
208 | ||
209 | ret = set_tracing_cpumask(cpumap); | |
210 | cpu_map__put(cpumap); | |
211 | return ret; | |
212 | } | |
213 | ||
78b83e8b NK |
214 | static int __set_tracing_filter(const char *filter_file, struct list_head *funcs) |
215 | { | |
216 | struct filter_entry *pos; | |
217 | ||
218 | list_for_each_entry(pos, funcs, list) { | |
219 | if (append_tracing_file(filter_file, pos->name) < 0) | |
220 | return -1; | |
221 | } | |
222 | ||
223 | return 0; | |
224 | } | |
225 | ||
226 | static int set_tracing_filters(struct perf_ftrace *ftrace) | |
227 | { | |
228 | int ret; | |
229 | ||
230 | ret = __set_tracing_filter("set_ftrace_filter", &ftrace->filters); | |
231 | if (ret < 0) | |
232 | return ret; | |
233 | ||
234 | ret = __set_tracing_filter("set_ftrace_notrace", &ftrace->notrace); | |
235 | if (ret < 0) | |
236 | return ret; | |
237 | ||
238 | ret = __set_tracing_filter("set_graph_function", &ftrace->graph_funcs); | |
239 | if (ret < 0) | |
240 | return ret; | |
241 | ||
242 | /* old kernels do not have this filter */ | |
243 | __set_tracing_filter("set_graph_notrace", &ftrace->nograph_funcs); | |
244 | ||
245 | return ret; | |
246 | } | |
247 | ||
248 | static void reset_tracing_filters(void) | |
249 | { | |
250 | write_tracing_file("set_ftrace_filter", " "); | |
251 | write_tracing_file("set_ftrace_notrace", " "); | |
252 | write_tracing_file("set_graph_function", " "); | |
253 | write_tracing_file("set_graph_notrace", " "); | |
254 | } | |
255 | ||
1096c35a NK |
256 | static int set_tracing_depth(struct perf_ftrace *ftrace) |
257 | { | |
258 | char buf[16]; | |
259 | ||
260 | if (ftrace->graph_depth == 0) | |
261 | return 0; | |
262 | ||
263 | if (ftrace->graph_depth < 0) { | |
264 | pr_err("invalid graph depth: %d\n", ftrace->graph_depth); | |
265 | return -1; | |
266 | } | |
267 | ||
268 | snprintf(buf, sizeof(buf), "%d", ftrace->graph_depth); | |
269 | ||
270 | if (write_tracing_file("max_graph_depth", buf) < 0) | |
271 | return -1; | |
272 | ||
273 | return 0; | |
274 | } | |
275 | ||
d01f4e8d NK |
276 | static int __cmd_ftrace(struct perf_ftrace *ftrace, int argc, const char **argv) |
277 | { | |
278 | char *trace_file; | |
279 | int trace_fd; | |
d01f4e8d NK |
280 | char buf[4096]; |
281 | struct pollfd pollfd = { | |
282 | .events = POLLIN, | |
283 | }; | |
284 | ||
285 | if (geteuid() != 0) { | |
286 | pr_err("ftrace only works for root!\n"); | |
287 | return -1; | |
288 | } | |
289 | ||
d01f4e8d NK |
290 | signal(SIGINT, sig_handler); |
291 | signal(SIGUSR1, sig_handler); | |
292 | signal(SIGCHLD, sig_handler); | |
58335964 | 293 | signal(SIGPIPE, sig_handler); |
d01f4e8d | 294 | |
63cd02d8 CD |
295 | if (reset_tracing_files(ftrace) < 0) { |
296 | pr_err("failed to reset ftrace\n"); | |
a9af6be5 | 297 | goto out; |
63cd02d8 | 298 | } |
d01f4e8d NK |
299 | |
300 | /* reset ftrace buffer */ | |
301 | if (write_tracing_file("trace", "0") < 0) | |
302 | goto out; | |
303 | ||
a9af6be5 NK |
304 | if (argc && perf_evlist__prepare_workload(ftrace->evlist, |
305 | &ftrace->target, argv, false, | |
306 | ftrace__workload_exec_failed_signal) < 0) { | |
d01f4e8d NK |
307 | goto out; |
308 | } | |
309 | ||
a9af6be5 NK |
310 | if (set_tracing_pid(ftrace) < 0) { |
311 | pr_err("failed to set ftrace pid\n"); | |
312 | goto out_reset; | |
d01f4e8d NK |
313 | } |
314 | ||
dc231032 NK |
315 | if (set_tracing_cpu(ftrace) < 0) { |
316 | pr_err("failed to set tracing cpumask\n"); | |
317 | goto out_reset; | |
318 | } | |
319 | ||
78b83e8b NK |
320 | if (set_tracing_filters(ftrace) < 0) { |
321 | pr_err("failed to set tracing filters\n"); | |
322 | goto out_reset; | |
323 | } | |
324 | ||
1096c35a NK |
325 | if (set_tracing_depth(ftrace) < 0) { |
326 | pr_err("failed to set graph depth\n"); | |
327 | goto out_reset; | |
328 | } | |
329 | ||
a9af6be5 NK |
330 | if (write_tracing_file("current_tracer", ftrace->tracer) < 0) { |
331 | pr_err("failed to set current_tracer to %s\n", ftrace->tracer); | |
332 | goto out_reset; | |
d01f4e8d NK |
333 | } |
334 | ||
29681bc5 NK |
335 | setup_pager(); |
336 | ||
d01f4e8d NK |
337 | trace_file = get_tracing_file("trace_pipe"); |
338 | if (!trace_file) { | |
339 | pr_err("failed to open trace_pipe\n"); | |
a9af6be5 | 340 | goto out_reset; |
d01f4e8d NK |
341 | } |
342 | ||
343 | trace_fd = open(trace_file, O_RDONLY); | |
344 | ||
345 | put_tracing_file(trace_file); | |
346 | ||
347 | if (trace_fd < 0) { | |
348 | pr_err("failed to open trace_pipe\n"); | |
a9af6be5 | 349 | goto out_reset; |
d01f4e8d NK |
350 | } |
351 | ||
352 | fcntl(trace_fd, F_SETFL, O_NONBLOCK); | |
353 | pollfd.fd = trace_fd; | |
354 | ||
355 | if (write_tracing_file("tracing_on", "1") < 0) { | |
356 | pr_err("can't enable tracing\n"); | |
357 | goto out_close_fd; | |
358 | } | |
359 | ||
360 | perf_evlist__start_workload(ftrace->evlist); | |
361 | ||
362 | while (!done) { | |
363 | if (poll(&pollfd, 1, -1) < 0) | |
364 | break; | |
365 | ||
366 | if (pollfd.revents & POLLIN) { | |
367 | int n = read(trace_fd, buf, sizeof(buf)); | |
368 | if (n < 0) | |
369 | break; | |
370 | if (fwrite(buf, n, 1, stdout) != 1) | |
371 | break; | |
372 | } | |
373 | } | |
374 | ||
375 | write_tracing_file("tracing_on", "0"); | |
376 | ||
377 | /* read remaining buffer contents */ | |
378 | while (true) { | |
379 | int n = read(trace_fd, buf, sizeof(buf)); | |
380 | if (n <= 0) | |
381 | break; | |
382 | if (fwrite(buf, n, 1, stdout) != 1) | |
383 | break; | |
384 | } | |
385 | ||
386 | out_close_fd: | |
387 | close(trace_fd); | |
a9af6be5 | 388 | out_reset: |
d01f4e8d | 389 | reset_tracing_files(ftrace); |
a9af6be5 | 390 | out: |
d01f4e8d NK |
391 | return done ? 0 : -1; |
392 | } | |
393 | ||
b05d1093 TS |
394 | static int perf_ftrace_config(const char *var, const char *value, void *cb) |
395 | { | |
396 | struct perf_ftrace *ftrace = cb; | |
397 | ||
8e99b6d4 | 398 | if (!strstarts(var, "ftrace.")) |
b05d1093 TS |
399 | return 0; |
400 | ||
401 | if (strcmp(var, "ftrace.tracer")) | |
402 | return -1; | |
403 | ||
404 | if (!strcmp(value, "function_graph") || | |
405 | !strcmp(value, "function")) { | |
406 | ftrace->tracer = value; | |
407 | return 0; | |
408 | } | |
409 | ||
410 | pr_err("Please select \"function_graph\" (default) or \"function\"\n"); | |
411 | return -1; | |
412 | } | |
413 | ||
78b83e8b NK |
414 | static int parse_filter_func(const struct option *opt, const char *str, |
415 | int unset __maybe_unused) | |
416 | { | |
417 | struct list_head *head = opt->value; | |
418 | struct filter_entry *entry; | |
419 | ||
420 | entry = malloc(sizeof(*entry) + strlen(str) + 1); | |
421 | if (entry == NULL) | |
422 | return -ENOMEM; | |
423 | ||
424 | strcpy(entry->name, str); | |
425 | list_add_tail(&entry->list, head); | |
426 | ||
427 | return 0; | |
428 | } | |
429 | ||
430 | static void delete_filter_func(struct list_head *head) | |
431 | { | |
432 | struct filter_entry *pos, *tmp; | |
433 | ||
434 | list_for_each_entry_safe(pos, tmp, head, list) { | |
435 | list_del(&pos->list); | |
436 | free(pos); | |
437 | } | |
438 | } | |
439 | ||
b0ad8ea6 | 440 | int cmd_ftrace(int argc, const char **argv) |
d01f4e8d NK |
441 | { |
442 | int ret; | |
443 | struct perf_ftrace ftrace = { | |
bf062bd2 | 444 | .tracer = DEFAULT_TRACER, |
d01f4e8d NK |
445 | .target = { .uid = UINT_MAX, }, |
446 | }; | |
447 | const char * const ftrace_usage[] = { | |
a9af6be5 | 448 | "perf ftrace [<options>] [<command>]", |
d01f4e8d NK |
449 | "perf ftrace [<options>] -- <command> [<options>]", |
450 | NULL | |
451 | }; | |
452 | const struct option ftrace_options[] = { | |
453 | OPT_STRING('t', "tracer", &ftrace.tracer, "tracer", | |
ec347870 | 454 | "tracer to use: function_graph(default) or function"), |
a9af6be5 NK |
455 | OPT_STRING('p', "pid", &ftrace.target.pid, "pid", |
456 | "trace on existing process id"), | |
d01f4e8d NK |
457 | OPT_INCR('v', "verbose", &verbose, |
458 | "be more verbose"), | |
dc231032 NK |
459 | OPT_BOOLEAN('a', "all-cpus", &ftrace.target.system_wide, |
460 | "system-wide collection from all CPUs"), | |
461 | OPT_STRING('C', "cpu", &ftrace.target.cpu_list, "cpu", | |
462 | "list of cpus to monitor"), | |
78b83e8b NK |
463 | OPT_CALLBACK('T', "trace-funcs", &ftrace.filters, "func", |
464 | "trace given functions only", parse_filter_func), | |
465 | OPT_CALLBACK('N', "notrace-funcs", &ftrace.notrace, "func", | |
466 | "do not trace given functions", parse_filter_func), | |
467 | OPT_CALLBACK('G', "graph-funcs", &ftrace.graph_funcs, "func", | |
468 | "Set graph filter on given functions", parse_filter_func), | |
469 | OPT_CALLBACK('g', "nograph-funcs", &ftrace.nograph_funcs, "func", | |
470 | "Set nograph filter on given functions", parse_filter_func), | |
1096c35a NK |
471 | OPT_INTEGER('D', "graph-depth", &ftrace.graph_depth, |
472 | "Max depth for function graph tracer"), | |
d01f4e8d NK |
473 | OPT_END() |
474 | }; | |
475 | ||
78b83e8b NK |
476 | INIT_LIST_HEAD(&ftrace.filters); |
477 | INIT_LIST_HEAD(&ftrace.notrace); | |
478 | INIT_LIST_HEAD(&ftrace.graph_funcs); | |
479 | INIT_LIST_HEAD(&ftrace.nograph_funcs); | |
480 | ||
b05d1093 TS |
481 | ret = perf_config(perf_ftrace_config, &ftrace); |
482 | if (ret < 0) | |
483 | return -1; | |
484 | ||
d01f4e8d NK |
485 | argc = parse_options(argc, argv, ftrace_options, ftrace_usage, |
486 | PARSE_OPT_STOP_AT_NON_OPTION); | |
a9af6be5 | 487 | if (!argc && target__none(&ftrace.target)) |
d01f4e8d NK |
488 | usage_with_options(ftrace_usage, ftrace_options); |
489 | ||
a9af6be5 NK |
490 | ret = target__validate(&ftrace.target); |
491 | if (ret) { | |
492 | char errbuf[512]; | |
493 | ||
494 | target__strerror(&ftrace.target, ret, errbuf, 512); | |
495 | pr_err("%s\n", errbuf); | |
78b83e8b | 496 | goto out_delete_filters; |
a9af6be5 NK |
497 | } |
498 | ||
d01f4e8d | 499 | ftrace.evlist = perf_evlist__new(); |
78b83e8b NK |
500 | if (ftrace.evlist == NULL) { |
501 | ret = -ENOMEM; | |
502 | goto out_delete_filters; | |
503 | } | |
d01f4e8d NK |
504 | |
505 | ret = perf_evlist__create_maps(ftrace.evlist, &ftrace.target); | |
506 | if (ret < 0) | |
507 | goto out_delete_evlist; | |
508 | ||
d01f4e8d NK |
509 | ret = __cmd_ftrace(&ftrace, argc, argv); |
510 | ||
511 | out_delete_evlist: | |
512 | perf_evlist__delete(ftrace.evlist); | |
513 | ||
78b83e8b NK |
514 | out_delete_filters: |
515 | delete_filter_func(&ftrace.filters); | |
516 | delete_filter_func(&ftrace.notrace); | |
517 | delete_filter_func(&ftrace.graph_funcs); | |
518 | delete_filter_func(&ftrace.nograph_funcs); | |
519 | ||
d01f4e8d NK |
520 | return ret; |
521 | } |