Loading...
1/*
2 * builtin-probe.c
3 *
4 * Builtin probe command: Set up probe events by C expression
5 *
6 * Written by Masami Hiramatsu <mhiramat@redhat.com>
7 *
8 * This program is free software; you can redistribute it and/or modify
9 * it under the terms of the GNU General Public License as published by
10 * the Free Software Foundation; either version 2 of the License, or
11 * (at your option) any later version.
12 *
13 * This program is distributed in the hope that it will be useful,
14 * but WITHOUT ANY WARRANTY; without even the implied warranty of
15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
16 * GNU General Public License for more details.
17 *
18 * You should have received a copy of the GNU General Public License
19 * along with this program; if not, write to the Free Software
20 * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
21 *
22 */
23#include <sys/utsname.h>
24#include <sys/types.h>
25#include <sys/stat.h>
26#include <fcntl.h>
27#include <errno.h>
28#include <stdio.h>
29#include <unistd.h>
30#include <stdlib.h>
31#include <string.h>
32
33#include "perf.h"
34#include "builtin.h"
35#include "util/util.h"
36#include "util/strlist.h"
37#include "util/strfilter.h"
38#include "util/symbol.h"
39#include "util/debug.h"
40#include <subcmd/parse-options.h>
41#include "util/probe-finder.h"
42#include "util/probe-event.h"
43#include "util/probe-file.h"
44
45#define DEFAULT_VAR_FILTER "!__k???tab_* & !__crc_*"
46#define DEFAULT_FUNC_FILTER "!_*"
47#define DEFAULT_LIST_FILTER "*"
48
49/* Session management structure */
50static struct {
51 int command; /* Command short_name */
52 bool list_events;
53 bool uprobes;
54 bool quiet;
55 bool target_used;
56 int nevents;
57 struct perf_probe_event events[MAX_PROBES];
58 struct line_range line_range;
59 char *target;
60 struct strfilter *filter;
61 struct nsinfo *nsi;
62} params;
63
64/* Parse an event definition. Note that any error must die. */
65static int parse_probe_event(const char *str)
66{
67 struct perf_probe_event *pev = ¶ms.events[params.nevents];
68 int ret;
69
70 pr_debug("probe-definition(%d): %s\n", params.nevents, str);
71 if (++params.nevents == MAX_PROBES) {
72 pr_err("Too many probes (> %d) were specified.", MAX_PROBES);
73 return -1;
74 }
75
76 pev->uprobes = params.uprobes;
77 if (params.target) {
78 pev->target = strdup(params.target);
79 if (!pev->target)
80 return -ENOMEM;
81 params.target_used = true;
82 }
83
84 if (params.nsi)
85 pev->nsi = nsinfo__get(params.nsi);
86
87 /* Parse a perf-probe command into event */
88 ret = parse_perf_probe_command(str, pev);
89 pr_debug("%d arguments\n", pev->nargs);
90
91 return ret;
92}
93
94static int params_add_filter(const char *str)
95{
96 const char *err = NULL;
97 int ret = 0;
98
99 pr_debug2("Add filter: %s\n", str);
100 if (!params.filter) {
101 params.filter = strfilter__new(str, &err);
102 if (!params.filter)
103 ret = err ? -EINVAL : -ENOMEM;
104 } else
105 ret = strfilter__or(params.filter, str, &err);
106
107 if (ret == -EINVAL) {
108 pr_err("Filter parse error at %td.\n", err - str + 1);
109 pr_err("Source: \"%s\"\n", str);
110 pr_err(" %*c\n", (int)(err - str + 1), '^');
111 }
112
113 return ret;
114}
115
116static int set_target(const char *ptr)
117{
118 int found = 0;
119 const char *buf;
120
121 /*
122 * The first argument after options can be an absolute path
123 * to an executable / library or kernel module.
124 *
125 * TODO: Support relative path, and $PATH, $LD_LIBRARY_PATH,
126 * short module name.
127 */
128 if (!params.target && ptr && *ptr == '/') {
129 params.target = strdup(ptr);
130 if (!params.target)
131 return -ENOMEM;
132 params.target_used = false;
133
134 found = 1;
135 buf = ptr + (strlen(ptr) - 3);
136
137 if (strcmp(buf, ".ko"))
138 params.uprobes = true;
139
140 }
141
142 return found;
143}
144
145static int parse_probe_event_argv(int argc, const char **argv)
146{
147 int i, len, ret, found_target;
148 char *buf;
149
150 found_target = set_target(argv[0]);
151 if (found_target < 0)
152 return found_target;
153
154 if (found_target && argc == 1)
155 return 0;
156
157 /* Bind up rest arguments */
158 len = 0;
159 for (i = 0; i < argc; i++) {
160 if (i == 0 && found_target)
161 continue;
162
163 len += strlen(argv[i]) + 1;
164 }
165 buf = zalloc(len + 1);
166 if (buf == NULL)
167 return -ENOMEM;
168 len = 0;
169 for (i = 0; i < argc; i++) {
170 if (i == 0 && found_target)
171 continue;
172
173 len += sprintf(&buf[len], "%s ", argv[i]);
174 }
175 ret = parse_probe_event(buf);
176 free(buf);
177 return ret;
178}
179
180static int opt_set_target(const struct option *opt, const char *str,
181 int unset __maybe_unused)
182{
183 int ret = -ENOENT;
184 char *tmp;
185
186 if (str) {
187 if (!strcmp(opt->long_name, "exec"))
188 params.uprobes = true;
189 else if (!strcmp(opt->long_name, "module"))
190 params.uprobes = false;
191 else
192 return ret;
193
194 /* Expand given path to absolute path, except for modulename */
195 if (params.uprobes || strchr(str, '/')) {
196 tmp = nsinfo__realpath(str, params.nsi);
197 if (!tmp) {
198 pr_warning("Failed to get the absolute path of %s: %m\n", str);
199 return ret;
200 }
201 } else {
202 tmp = strdup(str);
203 if (!tmp)
204 return -ENOMEM;
205 }
206 free(params.target);
207 params.target = tmp;
208 params.target_used = false;
209 ret = 0;
210 }
211
212 return ret;
213}
214
215static int opt_set_target_ns(const struct option *opt __maybe_unused,
216 const char *str, int unset __maybe_unused)
217{
218 int ret = -ENOENT;
219 pid_t ns_pid;
220 struct nsinfo *nsip;
221
222 if (str) {
223 errno = 0;
224 ns_pid = (pid_t)strtol(str, NULL, 10);
225 if (errno != 0) {
226 ret = -errno;
227 pr_warning("Failed to parse %s as a pid: %s\n", str,
228 strerror(errno));
229 return ret;
230 }
231 nsip = nsinfo__new(ns_pid);
232 if (nsip && nsip->need_setns)
233 params.nsi = nsinfo__get(nsip);
234 nsinfo__put(nsip);
235
236 ret = 0;
237 }
238
239 return ret;
240}
241
242
243/* Command option callbacks */
244
245#ifdef HAVE_DWARF_SUPPORT
246static int opt_show_lines(const struct option *opt,
247 const char *str, int unset __maybe_unused)
248{
249 int ret = 0;
250
251 if (!str)
252 return 0;
253
254 if (params.command == 'L') {
255 pr_warning("Warning: more than one --line options are"
256 " detected. Only the first one is valid.\n");
257 return 0;
258 }
259
260 params.command = opt->short_name;
261 ret = parse_line_range_desc(str, ¶ms.line_range);
262
263 return ret;
264}
265
266static int opt_show_vars(const struct option *opt,
267 const char *str, int unset __maybe_unused)
268{
269 struct perf_probe_event *pev = ¶ms.events[params.nevents];
270 int ret;
271
272 if (!str)
273 return 0;
274
275 ret = parse_probe_event(str);
276 if (!ret && pev->nargs != 0) {
277 pr_err(" Error: '--vars' doesn't accept arguments.\n");
278 return -EINVAL;
279 }
280 params.command = opt->short_name;
281
282 return ret;
283}
284#else
285# define opt_show_lines NULL
286# define opt_show_vars NULL
287#endif
288static int opt_add_probe_event(const struct option *opt,
289 const char *str, int unset __maybe_unused)
290{
291 if (str) {
292 params.command = opt->short_name;
293 return parse_probe_event(str);
294 }
295
296 return 0;
297}
298
299static int opt_set_filter_with_command(const struct option *opt,
300 const char *str, int unset)
301{
302 if (!unset)
303 params.command = opt->short_name;
304
305 if (str)
306 return params_add_filter(str);
307
308 return 0;
309}
310
311static int opt_set_filter(const struct option *opt __maybe_unused,
312 const char *str, int unset __maybe_unused)
313{
314 if (str)
315 return params_add_filter(str);
316
317 return 0;
318}
319
320static int init_params(void)
321{
322 return line_range__init(¶ms.line_range);
323}
324
325static void cleanup_params(void)
326{
327 int i;
328
329 for (i = 0; i < params.nevents; i++)
330 clear_perf_probe_event(params.events + i);
331 line_range__clear(¶ms.line_range);
332 free(params.target);
333 strfilter__delete(params.filter);
334 nsinfo__put(params.nsi);
335 memset(¶ms, 0, sizeof(params));
336}
337
338static void pr_err_with_code(const char *msg, int err)
339{
340 char sbuf[STRERR_BUFSIZE];
341
342 pr_err("%s", msg);
343 pr_debug(" Reason: %s (Code: %d)",
344 str_error_r(-err, sbuf, sizeof(sbuf)), err);
345 pr_err("\n");
346}
347
348static int perf_add_probe_events(struct perf_probe_event *pevs, int npevs)
349{
350 int ret;
351 int i, k;
352 const char *event = NULL, *group = NULL;
353
354 ret = init_probe_symbol_maps(pevs->uprobes);
355 if (ret < 0)
356 return ret;
357
358 ret = convert_perf_probe_events(pevs, npevs);
359 if (ret < 0)
360 goto out_cleanup;
361
362 if (params.command == 'D') { /* it shows definition */
363 ret = show_probe_trace_events(pevs, npevs);
364 goto out_cleanup;
365 }
366
367 ret = apply_perf_probe_events(pevs, npevs);
368 if (ret < 0)
369 goto out_cleanup;
370
371 for (i = k = 0; i < npevs; i++)
372 k += pevs[i].ntevs;
373
374 pr_info("Added new event%s\n", (k > 1) ? "s:" : ":");
375 for (i = 0; i < npevs; i++) {
376 struct perf_probe_event *pev = &pevs[i];
377
378 for (k = 0; k < pev->ntevs; k++) {
379 struct probe_trace_event *tev = &pev->tevs[k];
380
381 /* We use tev's name for showing new events */
382 show_perf_probe_event(tev->group, tev->event, pev,
383 tev->point.module, false);
384
385 /* Save the last valid name */
386 event = tev->event;
387 group = tev->group;
388 }
389 }
390
391 /* Note that it is possible to skip all events because of blacklist */
392 if (event) {
393 /* Show how to use the event. */
394 pr_info("\nYou can now use it in all perf tools, such as:\n\n");
395 pr_info("\tperf record -e %s:%s -aR sleep 1\n\n", group, event);
396 }
397
398out_cleanup:
399 cleanup_perf_probe_events(pevs, npevs);
400 exit_probe_symbol_maps();
401 return ret;
402}
403
404static int del_perf_probe_caches(struct strfilter *filter)
405{
406 struct probe_cache *cache;
407 struct strlist *bidlist;
408 struct str_node *nd;
409 int ret;
410
411 bidlist = build_id_cache__list_all(false);
412 if (!bidlist) {
413 ret = -errno;
414 pr_debug("Failed to get buildids: %d\n", ret);
415 return ret ?: -ENOMEM;
416 }
417
418 strlist__for_each_entry(nd, bidlist) {
419 cache = probe_cache__new(nd->s, NULL);
420 if (!cache)
421 continue;
422 if (probe_cache__filter_purge(cache, filter) < 0 ||
423 probe_cache__commit(cache) < 0)
424 pr_warning("Failed to remove entries for %s\n", nd->s);
425 probe_cache__delete(cache);
426 }
427 return 0;
428}
429
430static int perf_del_probe_events(struct strfilter *filter)
431{
432 int ret, ret2, ufd = -1, kfd = -1;
433 char *str = strfilter__string(filter);
434 struct strlist *klist = NULL, *ulist = NULL;
435 struct str_node *ent;
436
437 if (!str)
438 return -EINVAL;
439
440 pr_debug("Delete filter: \'%s\'\n", str);
441
442 if (probe_conf.cache)
443 return del_perf_probe_caches(filter);
444
445 /* Get current event names */
446 ret = probe_file__open_both(&kfd, &ufd, PF_FL_RW);
447 if (ret < 0)
448 goto out;
449
450 klist = strlist__new(NULL, NULL);
451 ulist = strlist__new(NULL, NULL);
452 if (!klist || !ulist) {
453 ret = -ENOMEM;
454 goto out;
455 }
456
457 ret = probe_file__get_events(kfd, filter, klist);
458 if (ret == 0) {
459 strlist__for_each_entry(ent, klist)
460 pr_info("Removed event: %s\n", ent->s);
461
462 ret = probe_file__del_strlist(kfd, klist);
463 if (ret < 0)
464 goto error;
465 }
466
467 ret2 = probe_file__get_events(ufd, filter, ulist);
468 if (ret2 == 0) {
469 strlist__for_each_entry(ent, ulist)
470 pr_info("Removed event: %s\n", ent->s);
471
472 ret2 = probe_file__del_strlist(ufd, ulist);
473 if (ret2 < 0)
474 goto error;
475 }
476
477 if (ret == -ENOENT && ret2 == -ENOENT)
478 pr_warning("\"%s\" does not hit any event.\n", str);
479 else
480 ret = 0;
481
482error:
483 if (kfd >= 0)
484 close(kfd);
485 if (ufd >= 0)
486 close(ufd);
487out:
488 strlist__delete(klist);
489 strlist__delete(ulist);
490 free(str);
491
492 return ret;
493}
494
495#ifdef HAVE_DWARF_SUPPORT
496#define PROBEDEF_STR \
497 "[EVENT=]FUNC[@SRC][+OFF|%return|:RL|;PT]|SRC:AL|SRC;PT [[NAME=]ARG ...]"
498#else
499#define PROBEDEF_STR "[EVENT=]FUNC[+OFF|%return] [[NAME=]ARG ...]"
500#endif
501
502
503static int
504__cmd_probe(int argc, const char **argv)
505{
506 const char * const probe_usage[] = {
507 "perf probe [<options>] 'PROBEDEF' ['PROBEDEF' ...]",
508 "perf probe [<options>] --add 'PROBEDEF' [--add 'PROBEDEF' ...]",
509 "perf probe [<options>] --del '[GROUP:]EVENT' ...",
510 "perf probe --list [GROUP:]EVENT ...",
511#ifdef HAVE_DWARF_SUPPORT
512 "perf probe [<options>] --line 'LINEDESC'",
513 "perf probe [<options>] --vars 'PROBEPOINT'",
514#endif
515 "perf probe [<options>] --funcs",
516 NULL
517 };
518 struct option options[] = {
519 OPT_INCR('v', "verbose", &verbose,
520 "be more verbose (show parsed arguments, etc)"),
521 OPT_BOOLEAN('q', "quiet", ¶ms.quiet,
522 "be quiet (do not show any messages)"),
523 OPT_CALLBACK_DEFAULT('l', "list", NULL, "[GROUP:]EVENT",
524 "list up probe events",
525 opt_set_filter_with_command, DEFAULT_LIST_FILTER),
526 OPT_CALLBACK('d', "del", NULL, "[GROUP:]EVENT", "delete a probe event.",
527 opt_set_filter_with_command),
528 OPT_CALLBACK('a', "add", NULL, PROBEDEF_STR,
529 "probe point definition, where\n"
530 "\t\tGROUP:\tGroup name (optional)\n"
531 "\t\tEVENT:\tEvent name\n"
532 "\t\tFUNC:\tFunction name\n"
533 "\t\tOFF:\tOffset from function entry (in byte)\n"
534 "\t\t%return:\tPut the probe at function return\n"
535#ifdef HAVE_DWARF_SUPPORT
536 "\t\tSRC:\tSource code path\n"
537 "\t\tRL:\tRelative line number from function entry.\n"
538 "\t\tAL:\tAbsolute line number in file.\n"
539 "\t\tPT:\tLazy expression of line code.\n"
540 "\t\tARG:\tProbe argument (local variable name or\n"
541 "\t\t\tkprobe-tracer argument format.)\n",
542#else
543 "\t\tARG:\tProbe argument (kprobe-tracer argument format.)\n",
544#endif
545 opt_add_probe_event),
546 OPT_CALLBACK('D', "definition", NULL, PROBEDEF_STR,
547 "Show trace event definition of given traceevent for k/uprobe_events.",
548 opt_add_probe_event),
549 OPT_BOOLEAN('f', "force", &probe_conf.force_add, "forcibly add events"
550 " with existing name"),
551 OPT_CALLBACK('L', "line", NULL,
552 "FUNC[:RLN[+NUM|-RLN2]]|SRC:ALN[+NUM|-ALN2]",
553 "Show source code lines.", opt_show_lines),
554 OPT_CALLBACK('V', "vars", NULL,
555 "FUNC[@SRC][+OFF|%return|:RL|;PT]|SRC:AL|SRC;PT",
556 "Show accessible variables on PROBEDEF", opt_show_vars),
557 OPT_BOOLEAN('\0', "externs", &probe_conf.show_ext_vars,
558 "Show external variables too (with --vars only)"),
559 OPT_BOOLEAN('\0', "range", &probe_conf.show_location_range,
560 "Show variables location range in scope (with --vars only)"),
561 OPT_STRING('k', "vmlinux", &symbol_conf.vmlinux_name,
562 "file", "vmlinux pathname"),
563 OPT_STRING('s', "source", &symbol_conf.source_prefix,
564 "directory", "path to kernel source"),
565 OPT_BOOLEAN('\0', "no-inlines", &probe_conf.no_inlines,
566 "Don't search inlined functions"),
567 OPT__DRY_RUN(&probe_event_dry_run),
568 OPT_INTEGER('\0', "max-probes", &probe_conf.max_probes,
569 "Set how many probe points can be found for a probe."),
570 OPT_CALLBACK_DEFAULT('F', "funcs", NULL, "[FILTER]",
571 "Show potential probe-able functions.",
572 opt_set_filter_with_command, DEFAULT_FUNC_FILTER),
573 OPT_CALLBACK('\0', "filter", NULL,
574 "[!]FILTER", "Set a filter (with --vars/funcs only)\n"
575 "\t\t\t(default: \"" DEFAULT_VAR_FILTER "\" for --vars,\n"
576 "\t\t\t \"" DEFAULT_FUNC_FILTER "\" for --funcs)",
577 opt_set_filter),
578 OPT_CALLBACK('x', "exec", NULL, "executable|path",
579 "target executable name or path", opt_set_target),
580 OPT_CALLBACK('m', "module", NULL, "modname|path",
581 "target module name (for online) or path (for offline)",
582 opt_set_target),
583 OPT_BOOLEAN(0, "demangle", &symbol_conf.demangle,
584 "Enable symbol demangling"),
585 OPT_BOOLEAN(0, "demangle-kernel", &symbol_conf.demangle_kernel,
586 "Enable kernel symbol demangling"),
587 OPT_BOOLEAN(0, "cache", &probe_conf.cache, "Manipulate probe cache"),
588 OPT_STRING(0, "symfs", &symbol_conf.symfs, "directory",
589 "Look for files with symbols relative to this directory"),
590 OPT_CALLBACK(0, "target-ns", NULL, "pid",
591 "target pid for namespace contexts", opt_set_target_ns),
592 OPT_END()
593 };
594 int ret;
595
596 set_option_flag(options, 'a', "add", PARSE_OPT_EXCLUSIVE);
597 set_option_flag(options, 'd', "del", PARSE_OPT_EXCLUSIVE);
598 set_option_flag(options, 'D', "definition", PARSE_OPT_EXCLUSIVE);
599 set_option_flag(options, 'l', "list", PARSE_OPT_EXCLUSIVE);
600#ifdef HAVE_DWARF_SUPPORT
601 set_option_flag(options, 'L', "line", PARSE_OPT_EXCLUSIVE);
602 set_option_flag(options, 'V', "vars", PARSE_OPT_EXCLUSIVE);
603#else
604# define set_nobuild(s, l, c) set_option_nobuild(options, s, l, "NO_DWARF=1", c)
605 set_nobuild('L', "line", false);
606 set_nobuild('V', "vars", false);
607 set_nobuild('\0', "externs", false);
608 set_nobuild('\0', "range", false);
609 set_nobuild('k', "vmlinux", true);
610 set_nobuild('s', "source", true);
611 set_nobuild('\0', "no-inlines", true);
612# undef set_nobuild
613#endif
614 set_option_flag(options, 'F', "funcs", PARSE_OPT_EXCLUSIVE);
615
616 argc = parse_options(argc, argv, options, probe_usage,
617 PARSE_OPT_STOP_AT_NON_OPTION);
618 if (argc > 0) {
619 if (strcmp(argv[0], "-") == 0) {
620 usage_with_options_msg(probe_usage, options,
621 "'-' is not supported.\n");
622 }
623 if (params.command && params.command != 'a') {
624 usage_with_options_msg(probe_usage, options,
625 "another command except --add is set.\n");
626 }
627 ret = parse_probe_event_argv(argc, argv);
628 if (ret < 0) {
629 pr_err_with_code(" Error: Command Parse Error.", ret);
630 return ret;
631 }
632 params.command = 'a';
633 }
634
635 if (params.quiet) {
636 if (verbose != 0) {
637 pr_err(" Error: -v and -q are exclusive.\n");
638 return -EINVAL;
639 }
640 verbose = -1;
641 }
642
643 if (probe_conf.max_probes == 0)
644 probe_conf.max_probes = MAX_PROBES;
645
646 /*
647 * Only consider the user's kernel image path if given.
648 */
649 symbol_conf.try_vmlinux_path = (symbol_conf.vmlinux_name == NULL);
650
651 /*
652 * Except for --list, --del and --add, other command doesn't depend
653 * nor change running kernel. So if user gives offline vmlinux,
654 * ignore its buildid.
655 */
656 if (!strchr("lda", params.command) && symbol_conf.vmlinux_name)
657 symbol_conf.ignore_vmlinux_buildid = true;
658
659 switch (params.command) {
660 case 'l':
661 if (params.uprobes) {
662 pr_err(" Error: Don't use --list with --exec.\n");
663 parse_options_usage(probe_usage, options, "l", true);
664 parse_options_usage(NULL, options, "x", true);
665 return -EINVAL;
666 }
667 ret = show_perf_probe_events(params.filter);
668 if (ret < 0)
669 pr_err_with_code(" Error: Failed to show event list.", ret);
670 return ret;
671 case 'F':
672 ret = show_available_funcs(params.target, params.nsi,
673 params.filter, params.uprobes);
674 if (ret < 0)
675 pr_err_with_code(" Error: Failed to show functions.", ret);
676 return ret;
677#ifdef HAVE_DWARF_SUPPORT
678 case 'L':
679 ret = show_line_range(¶ms.line_range, params.target,
680 params.nsi, params.uprobes);
681 if (ret < 0)
682 pr_err_with_code(" Error: Failed to show lines.", ret);
683 return ret;
684 case 'V':
685 if (!params.filter)
686 params.filter = strfilter__new(DEFAULT_VAR_FILTER,
687 NULL);
688
689 ret = show_available_vars(params.events, params.nevents,
690 params.filter);
691 if (ret < 0)
692 pr_err_with_code(" Error: Failed to show vars.", ret);
693 return ret;
694#endif
695 case 'd':
696 ret = perf_del_probe_events(params.filter);
697 if (ret < 0) {
698 pr_err_with_code(" Error: Failed to delete events.", ret);
699 return ret;
700 }
701 break;
702 case 'D':
703 case 'a':
704
705 /* Ensure the last given target is used */
706 if (params.target && !params.target_used) {
707 pr_err(" Error: -x/-m must follow the probe definitions.\n");
708 parse_options_usage(probe_usage, options, "m", true);
709 parse_options_usage(NULL, options, "x", true);
710 return -EINVAL;
711 }
712
713 ret = perf_add_probe_events(params.events, params.nevents);
714 if (ret < 0) {
715 pr_err_with_code(" Error: Failed to add events.", ret);
716 return ret;
717 }
718 break;
719 default:
720 usage_with_options(probe_usage, options);
721 }
722 return 0;
723}
724
725int cmd_probe(int argc, const char **argv)
726{
727 int ret;
728
729 ret = init_params();
730 if (!ret) {
731 ret = __cmd_probe(argc, argv);
732 cleanup_params();
733 }
734
735 return ret < 0 ? ret : 0;
736}
1/*
2 * builtin-probe.c
3 *
4 * Builtin probe command: Set up probe events by C expression
5 *
6 * Written by Masami Hiramatsu <mhiramat@redhat.com>
7 *
8 * This program is free software; you can redistribute it and/or modify
9 * it under the terms of the GNU General Public License as published by
10 * the Free Software Foundation; either version 2 of the License, or
11 * (at your option) any later version.
12 *
13 * This program is distributed in the hope that it will be useful,
14 * but WITHOUT ANY WARRANTY; without even the implied warranty of
15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
16 * GNU General Public License for more details.
17 *
18 * You should have received a copy of the GNU General Public License
19 * along with this program; if not, write to the Free Software
20 * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
21 *
22 */
23#include <sys/utsname.h>
24#include <sys/types.h>
25#include <sys/stat.h>
26#include <fcntl.h>
27#include <errno.h>
28#include <stdio.h>
29#include <unistd.h>
30#include <stdlib.h>
31#include <string.h>
32
33#include "perf.h"
34#include "builtin.h"
35#include "util/util.h"
36#include "util/strlist.h"
37#include "util/strfilter.h"
38#include "util/symbol.h"
39#include "util/debug.h"
40#include <subcmd/parse-options.h>
41#include "util/probe-finder.h"
42#include "util/probe-event.h"
43#include "util/probe-file.h"
44
45#define DEFAULT_VAR_FILTER "!__k???tab_* & !__crc_*"
46#define DEFAULT_FUNC_FILTER "!_*"
47#define DEFAULT_LIST_FILTER "*"
48
49/* Session management structure */
50static struct {
51 int command; /* Command short_name */
52 bool list_events;
53 bool uprobes;
54 bool quiet;
55 bool target_used;
56 int nevents;
57 struct perf_probe_event events[MAX_PROBES];
58 struct line_range line_range;
59 char *target;
60 struct strfilter *filter;
61} params;
62
63/* Parse an event definition. Note that any error must die. */
64static int parse_probe_event(const char *str)
65{
66 struct perf_probe_event *pev = ¶ms.events[params.nevents];
67 int ret;
68
69 pr_debug("probe-definition(%d): %s\n", params.nevents, str);
70 if (++params.nevents == MAX_PROBES) {
71 pr_err("Too many probes (> %d) were specified.", MAX_PROBES);
72 return -1;
73 }
74
75 pev->uprobes = params.uprobes;
76 if (params.target) {
77 pev->target = strdup(params.target);
78 if (!pev->target)
79 return -ENOMEM;
80 params.target_used = true;
81 }
82
83 /* Parse a perf-probe command into event */
84 ret = parse_perf_probe_command(str, pev);
85 pr_debug("%d arguments\n", pev->nargs);
86
87 return ret;
88}
89
90static int params_add_filter(const char *str)
91{
92 const char *err = NULL;
93 int ret = 0;
94
95 pr_debug2("Add filter: %s\n", str);
96 if (!params.filter) {
97 params.filter = strfilter__new(str, &err);
98 if (!params.filter)
99 ret = err ? -EINVAL : -ENOMEM;
100 } else
101 ret = strfilter__or(params.filter, str, &err);
102
103 if (ret == -EINVAL) {
104 pr_err("Filter parse error at %td.\n", err - str + 1);
105 pr_err("Source: \"%s\"\n", str);
106 pr_err(" %*c\n", (int)(err - str + 1), '^');
107 }
108
109 return ret;
110}
111
112static int set_target(const char *ptr)
113{
114 int found = 0;
115 const char *buf;
116
117 /*
118 * The first argument after options can be an absolute path
119 * to an executable / library or kernel module.
120 *
121 * TODO: Support relative path, and $PATH, $LD_LIBRARY_PATH,
122 * short module name.
123 */
124 if (!params.target && ptr && *ptr == '/') {
125 params.target = strdup(ptr);
126 if (!params.target)
127 return -ENOMEM;
128 params.target_used = false;
129
130 found = 1;
131 buf = ptr + (strlen(ptr) - 3);
132
133 if (strcmp(buf, ".ko"))
134 params.uprobes = true;
135
136 }
137
138 return found;
139}
140
141static int parse_probe_event_argv(int argc, const char **argv)
142{
143 int i, len, ret, found_target;
144 char *buf;
145
146 found_target = set_target(argv[0]);
147 if (found_target < 0)
148 return found_target;
149
150 if (found_target && argc == 1)
151 return 0;
152
153 /* Bind up rest arguments */
154 len = 0;
155 for (i = 0; i < argc; i++) {
156 if (i == 0 && found_target)
157 continue;
158
159 len += strlen(argv[i]) + 1;
160 }
161 buf = zalloc(len + 1);
162 if (buf == NULL)
163 return -ENOMEM;
164 len = 0;
165 for (i = 0; i < argc; i++) {
166 if (i == 0 && found_target)
167 continue;
168
169 len += sprintf(&buf[len], "%s ", argv[i]);
170 }
171 ret = parse_probe_event(buf);
172 free(buf);
173 return ret;
174}
175
176static int opt_set_target(const struct option *opt, const char *str,
177 int unset __maybe_unused)
178{
179 int ret = -ENOENT;
180 char *tmp;
181
182 if (str) {
183 if (!strcmp(opt->long_name, "exec"))
184 params.uprobes = true;
185 else if (!strcmp(opt->long_name, "module"))
186 params.uprobes = false;
187 else
188 return ret;
189
190 /* Expand given path to absolute path, except for modulename */
191 if (params.uprobes || strchr(str, '/')) {
192 tmp = realpath(str, NULL);
193 if (!tmp) {
194 pr_warning("Failed to get the absolute path of %s: %m\n", str);
195 return ret;
196 }
197 } else {
198 tmp = strdup(str);
199 if (!tmp)
200 return -ENOMEM;
201 }
202 free(params.target);
203 params.target = tmp;
204 params.target_used = false;
205 ret = 0;
206 }
207
208 return ret;
209}
210
211/* Command option callbacks */
212
213#ifdef HAVE_DWARF_SUPPORT
214static int opt_show_lines(const struct option *opt,
215 const char *str, int unset __maybe_unused)
216{
217 int ret = 0;
218
219 if (!str)
220 return 0;
221
222 if (params.command == 'L') {
223 pr_warning("Warning: more than one --line options are"
224 " detected. Only the first one is valid.\n");
225 return 0;
226 }
227
228 params.command = opt->short_name;
229 ret = parse_line_range_desc(str, ¶ms.line_range);
230
231 return ret;
232}
233
234static int opt_show_vars(const struct option *opt,
235 const char *str, int unset __maybe_unused)
236{
237 struct perf_probe_event *pev = ¶ms.events[params.nevents];
238 int ret;
239
240 if (!str)
241 return 0;
242
243 ret = parse_probe_event(str);
244 if (!ret && pev->nargs != 0) {
245 pr_err(" Error: '--vars' doesn't accept arguments.\n");
246 return -EINVAL;
247 }
248 params.command = opt->short_name;
249
250 return ret;
251}
252#else
253# define opt_show_lines NULL
254# define opt_show_vars NULL
255#endif
256static int opt_add_probe_event(const struct option *opt,
257 const char *str, int unset __maybe_unused)
258{
259 if (str) {
260 params.command = opt->short_name;
261 return parse_probe_event(str);
262 }
263
264 return 0;
265}
266
267static int opt_set_filter_with_command(const struct option *opt,
268 const char *str, int unset)
269{
270 if (!unset)
271 params.command = opt->short_name;
272
273 if (str)
274 return params_add_filter(str);
275
276 return 0;
277}
278
279static int opt_set_filter(const struct option *opt __maybe_unused,
280 const char *str, int unset __maybe_unused)
281{
282 if (str)
283 return params_add_filter(str);
284
285 return 0;
286}
287
288static int init_params(void)
289{
290 return line_range__init(¶ms.line_range);
291}
292
293static void cleanup_params(void)
294{
295 int i;
296
297 for (i = 0; i < params.nevents; i++)
298 clear_perf_probe_event(params.events + i);
299 line_range__clear(¶ms.line_range);
300 free(params.target);
301 strfilter__delete(params.filter);
302 memset(¶ms, 0, sizeof(params));
303}
304
305static void pr_err_with_code(const char *msg, int err)
306{
307 char sbuf[STRERR_BUFSIZE];
308
309 pr_err("%s", msg);
310 pr_debug(" Reason: %s (Code: %d)",
311 str_error_r(-err, sbuf, sizeof(sbuf)), err);
312 pr_err("\n");
313}
314
315static int perf_add_probe_events(struct perf_probe_event *pevs, int npevs)
316{
317 int ret;
318 int i, k;
319 const char *event = NULL, *group = NULL;
320
321 ret = init_probe_symbol_maps(pevs->uprobes);
322 if (ret < 0)
323 return ret;
324
325 ret = convert_perf_probe_events(pevs, npevs);
326 if (ret < 0)
327 goto out_cleanup;
328
329 if (params.command == 'D') { /* it shows definition */
330 ret = show_probe_trace_events(pevs, npevs);
331 goto out_cleanup;
332 }
333
334 ret = apply_perf_probe_events(pevs, npevs);
335 if (ret < 0)
336 goto out_cleanup;
337
338 for (i = k = 0; i < npevs; i++)
339 k += pevs[i].ntevs;
340
341 pr_info("Added new event%s\n", (k > 1) ? "s:" : ":");
342 for (i = 0; i < npevs; i++) {
343 struct perf_probe_event *pev = &pevs[i];
344
345 for (k = 0; k < pev->ntevs; k++) {
346 struct probe_trace_event *tev = &pev->tevs[k];
347
348 /* We use tev's name for showing new events */
349 show_perf_probe_event(tev->group, tev->event, pev,
350 tev->point.module, false);
351
352 /* Save the last valid name */
353 event = tev->event;
354 group = tev->group;
355 }
356 }
357
358 /* Note that it is possible to skip all events because of blacklist */
359 if (event) {
360 /* Show how to use the event. */
361 pr_info("\nYou can now use it in all perf tools, such as:\n\n");
362 pr_info("\tperf record -e %s:%s -aR sleep 1\n\n", group, event);
363 }
364
365out_cleanup:
366 cleanup_perf_probe_events(pevs, npevs);
367 exit_probe_symbol_maps();
368 return ret;
369}
370
371static int del_perf_probe_caches(struct strfilter *filter)
372{
373 struct probe_cache *cache;
374 struct strlist *bidlist;
375 struct str_node *nd;
376 int ret;
377
378 bidlist = build_id_cache__list_all(false);
379 if (!bidlist) {
380 ret = -errno;
381 pr_debug("Failed to get buildids: %d\n", ret);
382 return ret ?: -ENOMEM;
383 }
384
385 strlist__for_each_entry(nd, bidlist) {
386 cache = probe_cache__new(nd->s);
387 if (!cache)
388 continue;
389 if (probe_cache__filter_purge(cache, filter) < 0 ||
390 probe_cache__commit(cache) < 0)
391 pr_warning("Failed to remove entries for %s\n", nd->s);
392 probe_cache__delete(cache);
393 }
394 return 0;
395}
396
397static int perf_del_probe_events(struct strfilter *filter)
398{
399 int ret, ret2, ufd = -1, kfd = -1;
400 char *str = strfilter__string(filter);
401 struct strlist *klist = NULL, *ulist = NULL;
402 struct str_node *ent;
403
404 if (!str)
405 return -EINVAL;
406
407 pr_debug("Delete filter: \'%s\'\n", str);
408
409 if (probe_conf.cache)
410 return del_perf_probe_caches(filter);
411
412 /* Get current event names */
413 ret = probe_file__open_both(&kfd, &ufd, PF_FL_RW);
414 if (ret < 0)
415 goto out;
416
417 klist = strlist__new(NULL, NULL);
418 ulist = strlist__new(NULL, NULL);
419 if (!klist || !ulist) {
420 ret = -ENOMEM;
421 goto out;
422 }
423
424 ret = probe_file__get_events(kfd, filter, klist);
425 if (ret == 0) {
426 strlist__for_each_entry(ent, klist)
427 pr_info("Removed event: %s\n", ent->s);
428
429 ret = probe_file__del_strlist(kfd, klist);
430 if (ret < 0)
431 goto error;
432 }
433
434 ret2 = probe_file__get_events(ufd, filter, ulist);
435 if (ret2 == 0) {
436 strlist__for_each_entry(ent, ulist)
437 pr_info("Removed event: %s\n", ent->s);
438
439 ret2 = probe_file__del_strlist(ufd, ulist);
440 if (ret2 < 0)
441 goto error;
442 }
443
444 if (ret == -ENOENT && ret2 == -ENOENT)
445 pr_debug("\"%s\" does not hit any event.\n", str);
446 /* Note that this is silently ignored */
447 ret = 0;
448
449error:
450 if (kfd >= 0)
451 close(kfd);
452 if (ufd >= 0)
453 close(ufd);
454out:
455 strlist__delete(klist);
456 strlist__delete(ulist);
457 free(str);
458
459 return ret;
460}
461
462#ifdef HAVE_DWARF_SUPPORT
463#define PROBEDEF_STR \
464 "[EVENT=]FUNC[@SRC][+OFF|%return|:RL|;PT]|SRC:AL|SRC;PT [[NAME=]ARG ...]"
465#else
466#define PROBEDEF_STR "[EVENT=]FUNC[+OFF|%return] [[NAME=]ARG ...]"
467#endif
468
469
470static int
471__cmd_probe(int argc, const char **argv, const char *prefix __maybe_unused)
472{
473 const char * const probe_usage[] = {
474 "perf probe [<options>] 'PROBEDEF' ['PROBEDEF' ...]",
475 "perf probe [<options>] --add 'PROBEDEF' [--add 'PROBEDEF' ...]",
476 "perf probe [<options>] --del '[GROUP:]EVENT' ...",
477 "perf probe --list [GROUP:]EVENT ...",
478#ifdef HAVE_DWARF_SUPPORT
479 "perf probe [<options>] --line 'LINEDESC'",
480 "perf probe [<options>] --vars 'PROBEPOINT'",
481#endif
482 "perf probe [<options>] --funcs",
483 NULL
484 };
485 struct option options[] = {
486 OPT_INCR('v', "verbose", &verbose,
487 "be more verbose (show parsed arguments, etc)"),
488 OPT_BOOLEAN('q', "quiet", ¶ms.quiet,
489 "be quiet (do not show any mesages)"),
490 OPT_CALLBACK_DEFAULT('l', "list", NULL, "[GROUP:]EVENT",
491 "list up probe events",
492 opt_set_filter_with_command, DEFAULT_LIST_FILTER),
493 OPT_CALLBACK('d', "del", NULL, "[GROUP:]EVENT", "delete a probe event.",
494 opt_set_filter_with_command),
495 OPT_CALLBACK('a', "add", NULL, PROBEDEF_STR,
496 "probe point definition, where\n"
497 "\t\tGROUP:\tGroup name (optional)\n"
498 "\t\tEVENT:\tEvent name\n"
499 "\t\tFUNC:\tFunction name\n"
500 "\t\tOFF:\tOffset from function entry (in byte)\n"
501 "\t\t%return:\tPut the probe at function return\n"
502#ifdef HAVE_DWARF_SUPPORT
503 "\t\tSRC:\tSource code path\n"
504 "\t\tRL:\tRelative line number from function entry.\n"
505 "\t\tAL:\tAbsolute line number in file.\n"
506 "\t\tPT:\tLazy expression of line code.\n"
507 "\t\tARG:\tProbe argument (local variable name or\n"
508 "\t\t\tkprobe-tracer argument format.)\n",
509#else
510 "\t\tARG:\tProbe argument (kprobe-tracer argument format.)\n",
511#endif
512 opt_add_probe_event),
513 OPT_CALLBACK('D', "definition", NULL, PROBEDEF_STR,
514 "Show trace event definition of given traceevent for k/uprobe_events.",
515 opt_add_probe_event),
516 OPT_BOOLEAN('f', "force", &probe_conf.force_add, "forcibly add events"
517 " with existing name"),
518 OPT_CALLBACK('L', "line", NULL,
519 "FUNC[:RLN[+NUM|-RLN2]]|SRC:ALN[+NUM|-ALN2]",
520 "Show source code lines.", opt_show_lines),
521 OPT_CALLBACK('V', "vars", NULL,
522 "FUNC[@SRC][+OFF|%return|:RL|;PT]|SRC:AL|SRC;PT",
523 "Show accessible variables on PROBEDEF", opt_show_vars),
524 OPT_BOOLEAN('\0', "externs", &probe_conf.show_ext_vars,
525 "Show external variables too (with --vars only)"),
526 OPT_BOOLEAN('\0', "range", &probe_conf.show_location_range,
527 "Show variables location range in scope (with --vars only)"),
528 OPT_STRING('k', "vmlinux", &symbol_conf.vmlinux_name,
529 "file", "vmlinux pathname"),
530 OPT_STRING('s', "source", &symbol_conf.source_prefix,
531 "directory", "path to kernel source"),
532 OPT_BOOLEAN('\0', "no-inlines", &probe_conf.no_inlines,
533 "Don't search inlined functions"),
534 OPT__DRY_RUN(&probe_event_dry_run),
535 OPT_INTEGER('\0', "max-probes", &probe_conf.max_probes,
536 "Set how many probe points can be found for a probe."),
537 OPT_CALLBACK_DEFAULT('F', "funcs", NULL, "[FILTER]",
538 "Show potential probe-able functions.",
539 opt_set_filter_with_command, DEFAULT_FUNC_FILTER),
540 OPT_CALLBACK('\0', "filter", NULL,
541 "[!]FILTER", "Set a filter (with --vars/funcs only)\n"
542 "\t\t\t(default: \"" DEFAULT_VAR_FILTER "\" for --vars,\n"
543 "\t\t\t \"" DEFAULT_FUNC_FILTER "\" for --funcs)",
544 opt_set_filter),
545 OPT_CALLBACK('x', "exec", NULL, "executable|path",
546 "target executable name or path", opt_set_target),
547 OPT_CALLBACK('m', "module", NULL, "modname|path",
548 "target module name (for online) or path (for offline)",
549 opt_set_target),
550 OPT_BOOLEAN(0, "demangle", &symbol_conf.demangle,
551 "Enable symbol demangling"),
552 OPT_BOOLEAN(0, "demangle-kernel", &symbol_conf.demangle_kernel,
553 "Enable kernel symbol demangling"),
554 OPT_BOOLEAN(0, "cache", &probe_conf.cache, "Manipulate probe cache"),
555 OPT_END()
556 };
557 int ret;
558
559 set_option_flag(options, 'a', "add", PARSE_OPT_EXCLUSIVE);
560 set_option_flag(options, 'd', "del", PARSE_OPT_EXCLUSIVE);
561 set_option_flag(options, 'D', "definition", PARSE_OPT_EXCLUSIVE);
562 set_option_flag(options, 'l', "list", PARSE_OPT_EXCLUSIVE);
563#ifdef HAVE_DWARF_SUPPORT
564 set_option_flag(options, 'L', "line", PARSE_OPT_EXCLUSIVE);
565 set_option_flag(options, 'V', "vars", PARSE_OPT_EXCLUSIVE);
566#else
567# define set_nobuild(s, l, c) set_option_nobuild(options, s, l, "NO_DWARF=1", c)
568 set_nobuild('L', "line", false);
569 set_nobuild('V', "vars", false);
570 set_nobuild('\0', "externs", false);
571 set_nobuild('\0', "range", false);
572 set_nobuild('k', "vmlinux", true);
573 set_nobuild('s', "source", true);
574 set_nobuild('\0', "no-inlines", true);
575# undef set_nobuild
576#endif
577 set_option_flag(options, 'F', "funcs", PARSE_OPT_EXCLUSIVE);
578
579 argc = parse_options(argc, argv, options, probe_usage,
580 PARSE_OPT_STOP_AT_NON_OPTION);
581 if (argc > 0) {
582 if (strcmp(argv[0], "-") == 0) {
583 usage_with_options_msg(probe_usage, options,
584 "'-' is not supported.\n");
585 }
586 if (params.command && params.command != 'a') {
587 usage_with_options_msg(probe_usage, options,
588 "another command except --add is set.\n");
589 }
590 ret = parse_probe_event_argv(argc, argv);
591 if (ret < 0) {
592 pr_err_with_code(" Error: Command Parse Error.", ret);
593 return ret;
594 }
595 params.command = 'a';
596 }
597
598 if (params.quiet) {
599 if (verbose != 0) {
600 pr_err(" Error: -v and -q are exclusive.\n");
601 return -EINVAL;
602 }
603 verbose = -1;
604 }
605
606 if (probe_conf.max_probes == 0)
607 probe_conf.max_probes = MAX_PROBES;
608
609 /*
610 * Only consider the user's kernel image path if given.
611 */
612 symbol_conf.try_vmlinux_path = (symbol_conf.vmlinux_name == NULL);
613
614 /*
615 * Except for --list, --del and --add, other command doesn't depend
616 * nor change running kernel. So if user gives offline vmlinux,
617 * ignore its buildid.
618 */
619 if (!strchr("lda", params.command) && symbol_conf.vmlinux_name)
620 symbol_conf.ignore_vmlinux_buildid = true;
621
622 switch (params.command) {
623 case 'l':
624 if (params.uprobes) {
625 pr_err(" Error: Don't use --list with --exec.\n");
626 parse_options_usage(probe_usage, options, "l", true);
627 parse_options_usage(NULL, options, "x", true);
628 return -EINVAL;
629 }
630 ret = show_perf_probe_events(params.filter);
631 if (ret < 0)
632 pr_err_with_code(" Error: Failed to show event list.", ret);
633 return ret;
634 case 'F':
635 ret = show_available_funcs(params.target, params.filter,
636 params.uprobes);
637 if (ret < 0)
638 pr_err_with_code(" Error: Failed to show functions.", ret);
639 return ret;
640#ifdef HAVE_DWARF_SUPPORT
641 case 'L':
642 ret = show_line_range(¶ms.line_range, params.target,
643 params.uprobes);
644 if (ret < 0)
645 pr_err_with_code(" Error: Failed to show lines.", ret);
646 return ret;
647 case 'V':
648 if (!params.filter)
649 params.filter = strfilter__new(DEFAULT_VAR_FILTER,
650 NULL);
651
652 ret = show_available_vars(params.events, params.nevents,
653 params.filter);
654 if (ret < 0)
655 pr_err_with_code(" Error: Failed to show vars.", ret);
656 return ret;
657#endif
658 case 'd':
659 ret = perf_del_probe_events(params.filter);
660 if (ret < 0) {
661 pr_err_with_code(" Error: Failed to delete events.", ret);
662 return ret;
663 }
664 break;
665 case 'D':
666 case 'a':
667
668 /* Ensure the last given target is used */
669 if (params.target && !params.target_used) {
670 pr_err(" Error: -x/-m must follow the probe definitions.\n");
671 parse_options_usage(probe_usage, options, "m", true);
672 parse_options_usage(NULL, options, "x", true);
673 return -EINVAL;
674 }
675
676 ret = perf_add_probe_events(params.events, params.nevents);
677 if (ret < 0) {
678 pr_err_with_code(" Error: Failed to add events.", ret);
679 return ret;
680 }
681 break;
682 default:
683 usage_with_options(probe_usage, options);
684 }
685 return 0;
686}
687
688int cmd_probe(int argc, const char **argv, const char *prefix)
689{
690 int ret;
691
692 ret = init_params();
693 if (!ret) {
694 ret = __cmd_probe(argc, argv, prefix);
695 cleanup_params();
696 }
697
698 return ret < 0 ? ret : 0;
699}