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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// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 * builtin-probe.c
4 *
5 * Builtin probe command: Set up probe events by C expression
6 *
7 * Written by Masami Hiramatsu <mhiramat@redhat.com>
8 */
9#include <sys/utsname.h>
10#include <sys/types.h>
11#include <sys/stat.h>
12#include <fcntl.h>
13#include <errno.h>
14#include <stdio.h>
15#include <unistd.h>
16#include <stdlib.h>
17#include <string.h>
18
19#include "builtin.h"
20#include "namespaces.h"
21#include "util/build-id.h"
22#include "util/strlist.h"
23#include "util/strfilter.h"
24#include "util/symbol.h"
25#include "util/symbol_conf.h"
26#include "util/debug.h"
27#include <subcmd/parse-options.h>
28#include "util/probe-finder.h"
29#include "util/probe-event.h"
30#include "util/probe-file.h"
31#include <linux/string.h>
32#include <linux/zalloc.h>
33
34#define DEFAULT_VAR_FILTER "!__k???tab_* & !__crc_*"
35#define DEFAULT_FUNC_FILTER "!_* & !*@plt"
36#define DEFAULT_LIST_FILTER "*"
37
38/* Session management structure */
39static struct {
40 int command; /* Command short_name */
41 bool list_events;
42 bool uprobes;
43 bool target_used;
44 int nevents;
45 struct perf_probe_event events[MAX_PROBES];
46 struct line_range line_range;
47 char *target;
48 struct strfilter *filter;
49 struct nsinfo *nsi;
50} *params;
51
52/* Parse an event definition. Note that any error must die. */
53static int parse_probe_event(const char *str)
54{
55 struct perf_probe_event *pev = ¶ms->events[params->nevents];
56 int ret;
57
58 pr_debug("probe-definition(%d): %s\n", params->nevents, str);
59 if (++params->nevents == MAX_PROBES) {
60 pr_err("Too many probes (> %d) were specified.", MAX_PROBES);
61 return -1;
62 }
63
64 pev->uprobes = params->uprobes;
65 if (params->target) {
66 pev->target = strdup(params->target);
67 if (!pev->target)
68 return -ENOMEM;
69 params->target_used = true;
70 }
71
72 pev->nsi = nsinfo__get(params->nsi);
73
74 /* Parse a perf-probe command into event */
75 ret = parse_perf_probe_command(str, pev);
76 pr_debug("%d arguments\n", pev->nargs);
77
78 return ret;
79}
80
81static int params_add_filter(const char *str)
82{
83 const char *err = NULL;
84 int ret = 0;
85
86 pr_debug2("Add filter: %s\n", str);
87 if (!params->filter) {
88 params->filter = strfilter__new(str, &err);
89 if (!params->filter)
90 ret = err ? -EINVAL : -ENOMEM;
91 } else
92 ret = strfilter__or(params->filter, str, &err);
93
94 if (ret == -EINVAL) {
95 pr_err("Filter parse error at %td.\n", err - str + 1);
96 pr_err("Source: \"%s\"\n", str);
97 pr_err(" %*c\n", (int)(err - str + 1), '^');
98 }
99
100 return ret;
101}
102
103static int set_target(const char *ptr)
104{
105 int found = 0;
106 const char *buf;
107
108 /*
109 * The first argument after options can be an absolute path
110 * to an executable / library or kernel module.
111 *
112 * TODO: Support relative path, and $PATH, $LD_LIBRARY_PATH,
113 * short module name.
114 */
115 if (!params->target && ptr && *ptr == '/') {
116 params->target = strdup(ptr);
117 if (!params->target)
118 return -ENOMEM;
119 params->target_used = false;
120
121 found = 1;
122 buf = ptr + (strlen(ptr) - 3);
123
124 if (strcmp(buf, ".ko"))
125 params->uprobes = true;
126
127 }
128
129 return found;
130}
131
132static int parse_probe_event_argv(int argc, const char **argv)
133{
134 int i, len, ret, found_target;
135 char *buf;
136
137 found_target = set_target(argv[0]);
138 if (found_target < 0)
139 return found_target;
140
141 if (found_target && argc == 1)
142 return 0;
143
144 /* Bind up rest arguments */
145 len = 0;
146 for (i = 0; i < argc; i++) {
147 if (i == 0 && found_target)
148 continue;
149
150 len += strlen(argv[i]) + 1;
151 }
152 buf = zalloc(len + 1);
153 if (buf == NULL)
154 return -ENOMEM;
155 len = 0;
156 for (i = 0; i < argc; i++) {
157 if (i == 0 && found_target)
158 continue;
159
160 len += sprintf(&buf[len], "%s ", argv[i]);
161 }
162 ret = parse_probe_event(buf);
163 free(buf);
164 return ret;
165}
166
167static int opt_set_target(const struct option *opt, const char *str,
168 int unset __maybe_unused)
169{
170 int ret = -ENOENT;
171 char *tmp;
172
173 if (str) {
174 if (!strcmp(opt->long_name, "exec"))
175 params->uprobes = true;
176 else if (!strcmp(opt->long_name, "module"))
177 params->uprobes = false;
178 else
179 return ret;
180
181 /* Expand given path to absolute path, except for modulename */
182 if (params->uprobes || strchr(str, '/')) {
183 tmp = nsinfo__realpath(str, params->nsi);
184 if (!tmp) {
185 pr_warning("Failed to get the absolute path of %s: %m\n", str);
186 return ret;
187 }
188 } else {
189 tmp = strdup(str);
190 if (!tmp)
191 return -ENOMEM;
192 }
193 free(params->target);
194 params->target = tmp;
195 params->target_used = false;
196 ret = 0;
197 }
198
199 return ret;
200}
201
202static int opt_set_target_ns(const struct option *opt __maybe_unused,
203 const char *str, int unset __maybe_unused)
204{
205 int ret = -ENOENT;
206 pid_t ns_pid;
207 struct nsinfo *nsip;
208
209 if (str) {
210 errno = 0;
211 ns_pid = (pid_t)strtol(str, NULL, 10);
212 if (errno != 0) {
213 ret = -errno;
214 pr_warning("Failed to parse %s as a pid: %s\n", str,
215 strerror(errno));
216 return ret;
217 }
218 nsip = nsinfo__new(ns_pid);
219 if (nsip && nsinfo__need_setns(nsip))
220 params->nsi = nsinfo__get(nsip);
221 nsinfo__put(nsip);
222
223 ret = 0;
224 }
225
226 return ret;
227}
228
229
230/* Command option callbacks */
231
232#ifdef HAVE_DWARF_SUPPORT
233static int opt_show_lines(const struct option *opt,
234 const char *str, int unset __maybe_unused)
235{
236 int ret = 0;
237
238 if (!str)
239 return 0;
240
241 if (params->command == 'L') {
242 pr_warning("Warning: more than one --line options are"
243 " detected. Only the first one is valid.\n");
244 return 0;
245 }
246
247 params->command = opt->short_name;
248 ret = parse_line_range_desc(str, ¶ms->line_range);
249
250 return ret;
251}
252
253static int opt_show_vars(const struct option *opt,
254 const char *str, int unset __maybe_unused)
255{
256 struct perf_probe_event *pev = ¶ms->events[params->nevents];
257 int ret;
258
259 if (!str)
260 return 0;
261
262 ret = parse_probe_event(str);
263 if (!ret && pev->nargs != 0) {
264 pr_err(" Error: '--vars' doesn't accept arguments.\n");
265 return -EINVAL;
266 }
267 params->command = opt->short_name;
268
269 return ret;
270}
271#else
272# define opt_show_lines NULL
273# define opt_show_vars NULL
274#endif
275static int opt_add_probe_event(const struct option *opt,
276 const char *str, int unset __maybe_unused)
277{
278 if (str) {
279 params->command = opt->short_name;
280 return parse_probe_event(str);
281 }
282
283 return 0;
284}
285
286static int opt_set_filter_with_command(const struct option *opt,
287 const char *str, int unset)
288{
289 if (!unset)
290 params->command = opt->short_name;
291
292 if (str)
293 return params_add_filter(str);
294
295 return 0;
296}
297
298static int opt_set_filter(const struct option *opt __maybe_unused,
299 const char *str, int unset __maybe_unused)
300{
301 if (str)
302 return params_add_filter(str);
303
304 return 0;
305}
306
307static int init_params(void)
308{
309 int ret;
310
311 params = calloc(1, sizeof(*params));
312 if (!params)
313 return -ENOMEM;
314
315 ret = line_range__init(¶ms->line_range);
316 if (ret)
317 zfree(¶ms);
318 return ret;
319}
320
321static void cleanup_params(void)
322{
323 int i;
324
325 for (i = 0; i < params->nevents; i++)
326 clear_perf_probe_event(params->events + i);
327 line_range__clear(¶ms->line_range);
328 free(params->target);
329 strfilter__delete(params->filter);
330 nsinfo__put(params->nsi);
331 zfree(¶ms);
332}
333
334static void pr_err_with_code(const char *msg, int err)
335{
336 char sbuf[STRERR_BUFSIZE];
337
338 pr_err("%s", msg);
339 pr_debug(" Reason: %s (Code: %d)",
340 str_error_r(-err, sbuf, sizeof(sbuf)), err);
341 pr_err("\n");
342}
343
344static int perf_add_probe_events(struct perf_probe_event *pevs, int npevs)
345{
346 int ret;
347 int i, k;
348 const char *event = NULL, *group = NULL;
349
350 ret = init_probe_symbol_maps(pevs->uprobes);
351 if (ret < 0)
352 return ret;
353
354 ret = convert_perf_probe_events(pevs, npevs);
355 if (ret < 0)
356 goto out_cleanup;
357
358 if (params->command == 'D') { /* it shows definition */
359 if (probe_conf.bootconfig)
360 ret = show_bootconfig_events(pevs, npevs);
361 else
362 ret = show_probe_trace_events(pevs, npevs);
363 goto out_cleanup;
364 }
365
366 ret = apply_perf_probe_events(pevs, npevs);
367 if (ret < 0)
368 goto out_cleanup;
369
370 for (i = k = 0; i < npevs; i++)
371 k += pevs[i].ntevs;
372
373 pr_info("Added new event%s\n", (k > 1) ? "s:" : ":");
374 for (i = 0; i < npevs; i++) {
375 struct perf_probe_event *pev = &pevs[i];
376
377 for (k = 0; k < pev->ntevs; k++) {
378 struct probe_trace_event *tev = &pev->tevs[k];
379 /* Skipped events have no event name */
380 if (!tev->event)
381 continue;
382
383 /* We use tev's name for showing new events */
384 show_perf_probe_event(tev->group, tev->event, pev,
385 tev->point.module, false);
386
387 /* Save the last valid name */
388 event = tev->event;
389 group = tev->group;
390 }
391 }
392
393 /* Note that it is possible to skip all events because of blacklist */
394 if (event) {
395#ifndef HAVE_LIBTRACEEVENT
396 pr_info("\nperf is not linked with libtraceevent, to use the new probe you can use tracefs:\n\n");
397 pr_info("\tcd /sys/kernel/tracing/\n");
398 pr_info("\techo 1 > events/%s/%s/enable\n", group, event);
399 pr_info("\techo 1 > tracing_on\n");
400 pr_info("\tcat trace_pipe\n");
401 pr_info("\tBefore removing the probe, echo 0 > events/%s/%s/enable\n", group, event);
402#else
403 /* Show how to use the event. */
404 pr_info("\nYou can now use it in all perf tools, such as:\n\n");
405 pr_info("\tperf record -e %s:%s -aR sleep 1\n\n", group, event);
406#endif
407 }
408
409out_cleanup:
410 cleanup_perf_probe_events(pevs, npevs);
411 exit_probe_symbol_maps();
412 return ret;
413}
414
415static int del_perf_probe_caches(struct strfilter *filter)
416{
417 struct probe_cache *cache;
418 struct strlist *bidlist;
419 struct str_node *nd;
420 int ret;
421
422 bidlist = build_id_cache__list_all(false);
423 if (!bidlist) {
424 ret = -errno;
425 pr_debug("Failed to get buildids: %d\n", ret);
426 return ret ?: -ENOMEM;
427 }
428
429 strlist__for_each_entry(nd, bidlist) {
430 cache = probe_cache__new(nd->s, NULL);
431 if (!cache)
432 continue;
433 if (probe_cache__filter_purge(cache, filter) < 0 ||
434 probe_cache__commit(cache) < 0)
435 pr_warning("Failed to remove entries for %s\n", nd->s);
436 probe_cache__delete(cache);
437 }
438 return 0;
439}
440
441static int perf_del_probe_events(struct strfilter *filter)
442{
443 int ret, ret2, ufd = -1, kfd = -1;
444 char *str = strfilter__string(filter);
445 struct strlist *klist = NULL, *ulist = NULL;
446 struct str_node *ent;
447
448 if (!str)
449 return -EINVAL;
450
451 pr_debug("Delete filter: \'%s\'\n", str);
452
453 if (probe_conf.cache)
454 return del_perf_probe_caches(filter);
455
456 /* Get current event names */
457 ret = probe_file__open_both(&kfd, &ufd, PF_FL_RW);
458 if (ret < 0)
459 goto out;
460
461 klist = strlist__new(NULL, NULL);
462 ulist = strlist__new(NULL, NULL);
463 if (!klist || !ulist) {
464 ret = -ENOMEM;
465 goto out;
466 }
467
468 ret = probe_file__get_events(kfd, filter, klist);
469 if (ret == 0) {
470 strlist__for_each_entry(ent, klist)
471 pr_info("Removed event: %s\n", ent->s);
472
473 ret = probe_file__del_strlist(kfd, klist);
474 if (ret < 0)
475 goto error;
476 } else if (ret == -ENOMEM)
477 goto error;
478
479 ret2 = probe_file__get_events(ufd, filter, ulist);
480 if (ret2 == 0) {
481 strlist__for_each_entry(ent, ulist)
482 pr_info("Removed event: %s\n", ent->s);
483
484 ret2 = probe_file__del_strlist(ufd, ulist);
485 if (ret2 < 0)
486 goto error;
487 } else if (ret2 == -ENOMEM)
488 goto error;
489
490 if (ret == -ENOENT && ret2 == -ENOENT)
491 pr_warning("\"%s\" does not hit any event.\n", str);
492 else
493 ret = 0;
494
495error:
496 if (kfd >= 0)
497 close(kfd);
498 if (ufd >= 0)
499 close(ufd);
500out:
501 strlist__delete(klist);
502 strlist__delete(ulist);
503 free(str);
504
505 return ret;
506}
507
508#ifdef HAVE_DWARF_SUPPORT
509#define PROBEDEF_STR \
510 "[EVENT=]FUNC[@SRC][+OFF|%return|:RL|;PT]|SRC:AL|SRC;PT [[NAME=]ARG ...]"
511#else
512#define PROBEDEF_STR "[EVENT=]FUNC[+OFF|%return] [[NAME=]ARG ...]"
513#endif
514
515
516static int
517__cmd_probe(int argc, const char **argv)
518{
519 const char * const probe_usage[] = {
520 "perf probe [<options>] 'PROBEDEF' ['PROBEDEF' ...]",
521 "perf probe [<options>] --add 'PROBEDEF' [--add 'PROBEDEF' ...]",
522 "perf probe [<options>] --del '[GROUP:]EVENT' ...",
523 "perf probe --list [GROUP:]EVENT ...",
524#ifdef HAVE_DWARF_SUPPORT
525 "perf probe [<options>] --line 'LINEDESC'",
526 "perf probe [<options>] --vars 'PROBEPOINT'",
527#endif
528 "perf probe [<options>] --funcs",
529 NULL
530 };
531 struct option options[] = {
532 OPT_INCR('v', "verbose", &verbose,
533 "be more verbose (show parsed arguments, etc)"),
534 OPT_BOOLEAN('q', "quiet", &quiet,
535 "be quiet (do not show any warnings or messages)"),
536 OPT_CALLBACK_DEFAULT('l', "list", NULL, "[GROUP:]EVENT",
537 "list up probe events",
538 opt_set_filter_with_command, DEFAULT_LIST_FILTER),
539 OPT_CALLBACK('d', "del", NULL, "[GROUP:]EVENT", "delete a probe event.",
540 opt_set_filter_with_command),
541 OPT_CALLBACK('a', "add", NULL, PROBEDEF_STR,
542 "probe point definition, where\n"
543 "\t\tGROUP:\tGroup name (optional)\n"
544 "\t\tEVENT:\tEvent name\n"
545 "\t\tFUNC:\tFunction name\n"
546 "\t\tOFF:\tOffset from function entry (in byte)\n"
547 "\t\t%return:\tPut the probe at function return\n"
548#ifdef HAVE_DWARF_SUPPORT
549 "\t\tSRC:\tSource code path\n"
550 "\t\tRL:\tRelative line number from function entry.\n"
551 "\t\tAL:\tAbsolute line number in file.\n"
552 "\t\tPT:\tLazy expression of line code.\n"
553 "\t\tARG:\tProbe argument (local variable name or\n"
554 "\t\t\tkprobe-tracer argument format.)\n",
555#else
556 "\t\tARG:\tProbe argument (kprobe-tracer argument format.)\n",
557#endif
558 opt_add_probe_event),
559 OPT_CALLBACK('D', "definition", NULL, PROBEDEF_STR,
560 "Show trace event definition of given traceevent for k/uprobe_events.",
561 opt_add_probe_event),
562 OPT_BOOLEAN('f', "force", &probe_conf.force_add, "forcibly add events"
563 " with existing name"),
564 OPT_CALLBACK('L', "line", NULL,
565 "FUNC[:RLN[+NUM|-RLN2]]|SRC:ALN[+NUM|-ALN2]",
566 "Show source code lines.", opt_show_lines),
567 OPT_CALLBACK('V', "vars", NULL,
568 "FUNC[@SRC][+OFF|%return|:RL|;PT]|SRC:AL|SRC;PT",
569 "Show accessible variables on PROBEDEF", opt_show_vars),
570 OPT_BOOLEAN('\0', "externs", &probe_conf.show_ext_vars,
571 "Show external variables too (with --vars only)"),
572 OPT_BOOLEAN('\0', "range", &probe_conf.show_location_range,
573 "Show variables location range in scope (with --vars only)"),
574 OPT_STRING('k', "vmlinux", &symbol_conf.vmlinux_name,
575 "file", "vmlinux pathname"),
576 OPT_STRING('s', "source", &symbol_conf.source_prefix,
577 "directory", "path to kernel source"),
578 OPT_BOOLEAN('\0', "no-inlines", &probe_conf.no_inlines,
579 "Don't search inlined functions"),
580 OPT__DRY_RUN(&probe_event_dry_run),
581 OPT_INTEGER('\0', "max-probes", &probe_conf.max_probes,
582 "Set how many probe points can be found for a probe."),
583 OPT_CALLBACK_DEFAULT('F', "funcs", NULL, "[FILTER]",
584 "Show potential probe-able functions.",
585 opt_set_filter_with_command, DEFAULT_FUNC_FILTER),
586 OPT_CALLBACK('\0', "filter", NULL,
587 "[!]FILTER", "Set a filter (with --vars/funcs only)\n"
588 "\t\t\t(default: \"" DEFAULT_VAR_FILTER "\" for --vars,\n"
589 "\t\t\t \"" DEFAULT_FUNC_FILTER "\" for --funcs)",
590 opt_set_filter),
591 OPT_CALLBACK('x', "exec", NULL, "executable|path",
592 "target executable name or path", opt_set_target),
593 OPT_CALLBACK('m', "module", NULL, "modname|path",
594 "target module name (for online) or path (for offline)",
595 opt_set_target),
596 OPT_BOOLEAN(0, "demangle", &symbol_conf.demangle,
597 "Enable symbol demangling"),
598 OPT_BOOLEAN(0, "demangle-kernel", &symbol_conf.demangle_kernel,
599 "Enable kernel symbol demangling"),
600 OPT_BOOLEAN(0, "cache", &probe_conf.cache, "Manipulate probe cache"),
601 OPT_STRING(0, "symfs", &symbol_conf.symfs, "directory",
602 "Look for files with symbols relative to this directory"),
603 OPT_CALLBACK(0, "target-ns", NULL, "pid",
604 "target pid for namespace contexts", opt_set_target_ns),
605 OPT_BOOLEAN(0, "bootconfig", &probe_conf.bootconfig,
606 "Output probe definition with bootconfig format"),
607 OPT_END()
608 };
609 int ret;
610
611 set_option_flag(options, 'a', "add", PARSE_OPT_EXCLUSIVE);
612 set_option_flag(options, 'd', "del", PARSE_OPT_EXCLUSIVE);
613 set_option_flag(options, 'D', "definition", PARSE_OPT_EXCLUSIVE);
614 set_option_flag(options, 'l', "list", PARSE_OPT_EXCLUSIVE);
615#ifdef HAVE_DWARF_SUPPORT
616 set_option_flag(options, 'L', "line", PARSE_OPT_EXCLUSIVE);
617 set_option_flag(options, 'V', "vars", PARSE_OPT_EXCLUSIVE);
618#else
619# define set_nobuild(s, l, c) set_option_nobuild(options, s, l, "NO_DWARF=1", c)
620 set_nobuild('L', "line", false);
621 set_nobuild('V', "vars", false);
622 set_nobuild('\0', "externs", false);
623 set_nobuild('\0', "range", false);
624 set_nobuild('k', "vmlinux", true);
625 set_nobuild('s', "source", true);
626 set_nobuild('\0', "no-inlines", true);
627# undef set_nobuild
628#endif
629 set_option_flag(options, 'F', "funcs", PARSE_OPT_EXCLUSIVE);
630
631 argc = parse_options(argc, argv, options, probe_usage,
632 PARSE_OPT_STOP_AT_NON_OPTION);
633
634 if (quiet) {
635 if (verbose != 0) {
636 pr_err(" Error: -v and -q are exclusive.\n");
637 return -EINVAL;
638 }
639 verbose = -1;
640 }
641
642 if (argc > 0) {
643 if (strcmp(argv[0], "-") == 0) {
644 usage_with_options_msg(probe_usage, options,
645 "'-' is not supported.\n");
646 }
647 if (params->command && params->command != 'a') {
648 usage_with_options_msg(probe_usage, options,
649 "another command except --add is set.\n");
650 }
651 ret = parse_probe_event_argv(argc, argv);
652 if (ret < 0) {
653 pr_err_with_code(" Error: Command Parse Error.", ret);
654 return ret;
655 }
656 params->command = 'a';
657 }
658
659 ret = symbol__validate_sym_arguments();
660 if (ret)
661 return ret;
662
663 if (probe_conf.max_probes == 0)
664 probe_conf.max_probes = MAX_PROBES;
665
666 /*
667 * Only consider the user's kernel image path if given.
668 */
669 symbol_conf.try_vmlinux_path = (symbol_conf.vmlinux_name == NULL);
670
671 /*
672 * Except for --list, --del and --add, other command doesn't depend
673 * nor change running kernel. So if user gives offline vmlinux,
674 * ignore its buildid.
675 */
676 if (!strchr("lda", params->command) && symbol_conf.vmlinux_name)
677 symbol_conf.ignore_vmlinux_buildid = true;
678
679 switch (params->command) {
680 case 'l':
681 if (params->uprobes) {
682 pr_err(" Error: Don't use --list with --exec.\n");
683 parse_options_usage(probe_usage, options, "l", true);
684 parse_options_usage(NULL, options, "x", true);
685 return -EINVAL;
686 }
687 ret = show_perf_probe_events(params->filter);
688 if (ret < 0)
689 pr_err_with_code(" Error: Failed to show event list.", ret);
690 return ret;
691 case 'F':
692 ret = show_available_funcs(params->target, params->nsi,
693 params->filter, params->uprobes);
694 if (ret < 0)
695 pr_err_with_code(" Error: Failed to show functions.", ret);
696 return ret;
697#ifdef HAVE_DWARF_SUPPORT
698 case 'L':
699 ret = show_line_range(¶ms->line_range, params->target,
700 params->nsi, params->uprobes);
701 if (ret < 0)
702 pr_err_with_code(" Error: Failed to show lines.", ret);
703 return ret;
704 case 'V':
705 if (!params->filter)
706 params->filter = strfilter__new(DEFAULT_VAR_FILTER,
707 NULL);
708
709 ret = show_available_vars(params->events, params->nevents,
710 params->filter);
711 if (ret < 0)
712 pr_err_with_code(" Error: Failed to show vars.", ret);
713 return ret;
714#endif
715 case 'd':
716 ret = perf_del_probe_events(params->filter);
717 if (ret < 0) {
718 pr_err_with_code(" Error: Failed to delete events.", ret);
719 return ret;
720 }
721 break;
722 case 'D':
723 if (probe_conf.bootconfig && params->uprobes) {
724 pr_err(" Error: --bootconfig doesn't support uprobes.\n");
725 return -EINVAL;
726 }
727 fallthrough;
728 case 'a':
729
730 /* Ensure the last given target is used */
731 if (params->target && !params->target_used) {
732 pr_err(" Error: -x/-m must follow the probe definitions.\n");
733 parse_options_usage(probe_usage, options, "m", true);
734 parse_options_usage(NULL, options, "x", true);
735 return -EINVAL;
736 }
737
738 ret = perf_add_probe_events(params->events, params->nevents);
739 if (ret < 0) {
740
741 /*
742 * When perf_add_probe_events() fails it calls
743 * cleanup_perf_probe_events(pevs, npevs), i.e.
744 * cleanup_perf_probe_events(params->events, params->nevents), which
745 * will call clear_perf_probe_event(), so set nevents to zero
746 * to avoid cleanup_params() to call clear_perf_probe_event() again
747 * on the same pevs.
748 */
749 params->nevents = 0;
750 pr_err_with_code(" Error: Failed to add events.", ret);
751 return ret;
752 }
753 break;
754 default:
755 usage_with_options(probe_usage, options);
756 }
757 return 0;
758}
759
760int cmd_probe(int argc, const char **argv)
761{
762 int ret;
763
764 ret = init_params();
765 if (!ret) {
766 ret = __cmd_probe(argc, argv);
767 cleanup_params();
768 }
769
770 return ret < 0 ? ret : 0;
771}