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