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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 return line_range__init(¶ms.line_range);
310}
311
312static void cleanup_params(void)
313{
314 int i;
315
316 for (i = 0; i < params.nevents; i++)
317 clear_perf_probe_event(params.events + i);
318 line_range__clear(¶ms.line_range);
319 free(params.target);
320 strfilter__delete(params.filter);
321 nsinfo__put(params.nsi);
322 memset(¶ms, 0, sizeof(params));
323}
324
325static void pr_err_with_code(const char *msg, int err)
326{
327 char sbuf[STRERR_BUFSIZE];
328
329 pr_err("%s", msg);
330 pr_debug(" Reason: %s (Code: %d)",
331 str_error_r(-err, sbuf, sizeof(sbuf)), err);
332 pr_err("\n");
333}
334
335static int perf_add_probe_events(struct perf_probe_event *pevs, int npevs)
336{
337 int ret;
338 int i, k;
339 const char *event = NULL, *group = NULL;
340
341 ret = init_probe_symbol_maps(pevs->uprobes);
342 if (ret < 0)
343 return ret;
344
345 ret = convert_perf_probe_events(pevs, npevs);
346 if (ret < 0)
347 goto out_cleanup;
348
349 if (params.command == 'D') { /* it shows definition */
350 if (probe_conf.bootconfig)
351 ret = show_bootconfig_events(pevs, npevs);
352 else
353 ret = show_probe_trace_events(pevs, npevs);
354 goto out_cleanup;
355 }
356
357 ret = apply_perf_probe_events(pevs, npevs);
358 if (ret < 0)
359 goto out_cleanup;
360
361 for (i = k = 0; i < npevs; i++)
362 k += pevs[i].ntevs;
363
364 pr_info("Added new event%s\n", (k > 1) ? "s:" : ":");
365 for (i = 0; i < npevs; i++) {
366 struct perf_probe_event *pev = &pevs[i];
367
368 for (k = 0; k < pev->ntevs; k++) {
369 struct probe_trace_event *tev = &pev->tevs[k];
370 /* Skipped events have no event name */
371 if (!tev->event)
372 continue;
373
374 /* We use tev's name for showing new events */
375 show_perf_probe_event(tev->group, tev->event, pev,
376 tev->point.module, false);
377
378 /* Save the last valid name */
379 event = tev->event;
380 group = tev->group;
381 }
382 }
383
384 /* Note that it is possible to skip all events because of blacklist */
385 if (event) {
386 /* Show how to use the event. */
387 pr_info("\nYou can now use it in all perf tools, such as:\n\n");
388 pr_info("\tperf record -e %s:%s -aR sleep 1\n\n", group, event);
389 }
390
391out_cleanup:
392 cleanup_perf_probe_events(pevs, npevs);
393 exit_probe_symbol_maps();
394 return ret;
395}
396
397static int del_perf_probe_caches(struct strfilter *filter)
398{
399 struct probe_cache *cache;
400 struct strlist *bidlist;
401 struct str_node *nd;
402 int ret;
403
404 bidlist = build_id_cache__list_all(false);
405 if (!bidlist) {
406 ret = -errno;
407 pr_debug("Failed to get buildids: %d\n", ret);
408 return ret ?: -ENOMEM;
409 }
410
411 strlist__for_each_entry(nd, bidlist) {
412 cache = probe_cache__new(nd->s, NULL);
413 if (!cache)
414 continue;
415 if (probe_cache__filter_purge(cache, filter) < 0 ||
416 probe_cache__commit(cache) < 0)
417 pr_warning("Failed to remove entries for %s\n", nd->s);
418 probe_cache__delete(cache);
419 }
420 return 0;
421}
422
423static int perf_del_probe_events(struct strfilter *filter)
424{
425 int ret, ret2, ufd = -1, kfd = -1;
426 char *str = strfilter__string(filter);
427 struct strlist *klist = NULL, *ulist = NULL;
428 struct str_node *ent;
429
430 if (!str)
431 return -EINVAL;
432
433 pr_debug("Delete filter: \'%s\'\n", str);
434
435 if (probe_conf.cache)
436 return del_perf_probe_caches(filter);
437
438 /* Get current event names */
439 ret = probe_file__open_both(&kfd, &ufd, PF_FL_RW);
440 if (ret < 0)
441 goto out;
442
443 klist = strlist__new(NULL, NULL);
444 ulist = strlist__new(NULL, NULL);
445 if (!klist || !ulist) {
446 ret = -ENOMEM;
447 goto out;
448 }
449
450 ret = probe_file__get_events(kfd, filter, klist);
451 if (ret == 0) {
452 strlist__for_each_entry(ent, klist)
453 pr_info("Removed event: %s\n", ent->s);
454
455 ret = probe_file__del_strlist(kfd, klist);
456 if (ret < 0)
457 goto error;
458 } else if (ret == -ENOMEM)
459 goto error;
460
461 ret2 = probe_file__get_events(ufd, filter, ulist);
462 if (ret2 == 0) {
463 strlist__for_each_entry(ent, ulist)
464 pr_info("Removed event: %s\n", ent->s);
465
466 ret2 = probe_file__del_strlist(ufd, ulist);
467 if (ret2 < 0)
468 goto error;
469 } else if (ret2 == -ENOMEM)
470 goto error;
471
472 if (ret == -ENOENT && ret2 == -ENOENT)
473 pr_warning("\"%s\" does not hit any event.\n", str);
474 else
475 ret = 0;
476
477error:
478 if (kfd >= 0)
479 close(kfd);
480 if (ufd >= 0)
481 close(ufd);
482out:
483 strlist__delete(klist);
484 strlist__delete(ulist);
485 free(str);
486
487 return ret;
488}
489
490#ifdef HAVE_DWARF_SUPPORT
491#define PROBEDEF_STR \
492 "[EVENT=]FUNC[@SRC][+OFF|%return|:RL|;PT]|SRC:AL|SRC;PT [[NAME=]ARG ...]"
493#else
494#define PROBEDEF_STR "[EVENT=]FUNC[+OFF|%return] [[NAME=]ARG ...]"
495#endif
496
497
498static int
499__cmd_probe(int argc, const char **argv)
500{
501 const char * const probe_usage[] = {
502 "perf probe [<options>] 'PROBEDEF' ['PROBEDEF' ...]",
503 "perf probe [<options>] --add 'PROBEDEF' [--add 'PROBEDEF' ...]",
504 "perf probe [<options>] --del '[GROUP:]EVENT' ...",
505 "perf probe --list [GROUP:]EVENT ...",
506#ifdef HAVE_DWARF_SUPPORT
507 "perf probe [<options>] --line 'LINEDESC'",
508 "perf probe [<options>] --vars 'PROBEPOINT'",
509#endif
510 "perf probe [<options>] --funcs",
511 NULL
512 };
513 struct option options[] = {
514 OPT_INCR('v', "verbose", &verbose,
515 "be more verbose (show parsed arguments, etc)"),
516 OPT_BOOLEAN('q', "quiet", &quiet,
517 "be quiet (do not show any warnings or messages)"),
518 OPT_CALLBACK_DEFAULT('l', "list", NULL, "[GROUP:]EVENT",
519 "list up probe events",
520 opt_set_filter_with_command, DEFAULT_LIST_FILTER),
521 OPT_CALLBACK('d', "del", NULL, "[GROUP:]EVENT", "delete a probe event.",
522 opt_set_filter_with_command),
523 OPT_CALLBACK('a', "add", NULL, PROBEDEF_STR,
524 "probe point definition, where\n"
525 "\t\tGROUP:\tGroup name (optional)\n"
526 "\t\tEVENT:\tEvent name\n"
527 "\t\tFUNC:\tFunction name\n"
528 "\t\tOFF:\tOffset from function entry (in byte)\n"
529 "\t\t%return:\tPut the probe at function return\n"
530#ifdef HAVE_DWARF_SUPPORT
531 "\t\tSRC:\tSource code path\n"
532 "\t\tRL:\tRelative line number from function entry.\n"
533 "\t\tAL:\tAbsolute line number in file.\n"
534 "\t\tPT:\tLazy expression of line code.\n"
535 "\t\tARG:\tProbe argument (local variable name or\n"
536 "\t\t\tkprobe-tracer argument format.)\n",
537#else
538 "\t\tARG:\tProbe argument (kprobe-tracer argument format.)\n",
539#endif
540 opt_add_probe_event),
541 OPT_CALLBACK('D', "definition", NULL, PROBEDEF_STR,
542 "Show trace event definition of given traceevent for k/uprobe_events.",
543 opt_add_probe_event),
544 OPT_BOOLEAN('f', "force", &probe_conf.force_add, "forcibly add events"
545 " with existing name"),
546 OPT_CALLBACK('L', "line", NULL,
547 "FUNC[:RLN[+NUM|-RLN2]]|SRC:ALN[+NUM|-ALN2]",
548 "Show source code lines.", opt_show_lines),
549 OPT_CALLBACK('V', "vars", NULL,
550 "FUNC[@SRC][+OFF|%return|:RL|;PT]|SRC:AL|SRC;PT",
551 "Show accessible variables on PROBEDEF", opt_show_vars),
552 OPT_BOOLEAN('\0', "externs", &probe_conf.show_ext_vars,
553 "Show external variables too (with --vars only)"),
554 OPT_BOOLEAN('\0', "range", &probe_conf.show_location_range,
555 "Show variables location range in scope (with --vars only)"),
556 OPT_STRING('k', "vmlinux", &symbol_conf.vmlinux_name,
557 "file", "vmlinux pathname"),
558 OPT_STRING('s', "source", &symbol_conf.source_prefix,
559 "directory", "path to kernel source"),
560 OPT_BOOLEAN('\0', "no-inlines", &probe_conf.no_inlines,
561 "Don't search inlined functions"),
562 OPT__DRY_RUN(&probe_event_dry_run),
563 OPT_INTEGER('\0', "max-probes", &probe_conf.max_probes,
564 "Set how many probe points can be found for a probe."),
565 OPT_CALLBACK_DEFAULT('F', "funcs", NULL, "[FILTER]",
566 "Show potential probe-able functions.",
567 opt_set_filter_with_command, DEFAULT_FUNC_FILTER),
568 OPT_CALLBACK('\0', "filter", NULL,
569 "[!]FILTER", "Set a filter (with --vars/funcs only)\n"
570 "\t\t\t(default: \"" DEFAULT_VAR_FILTER "\" for --vars,\n"
571 "\t\t\t \"" DEFAULT_FUNC_FILTER "\" for --funcs)",
572 opt_set_filter),
573 OPT_CALLBACK('x', "exec", NULL, "executable|path",
574 "target executable name or path", opt_set_target),
575 OPT_CALLBACK('m', "module", NULL, "modname|path",
576 "target module name (for online) or path (for offline)",
577 opt_set_target),
578 OPT_BOOLEAN(0, "demangle", &symbol_conf.demangle,
579 "Enable symbol demangling"),
580 OPT_BOOLEAN(0, "demangle-kernel", &symbol_conf.demangle_kernel,
581 "Enable kernel symbol demangling"),
582 OPT_BOOLEAN(0, "cache", &probe_conf.cache, "Manipulate probe cache"),
583 OPT_STRING(0, "symfs", &symbol_conf.symfs, "directory",
584 "Look for files with symbols relative to this directory"),
585 OPT_CALLBACK(0, "target-ns", NULL, "pid",
586 "target pid for namespace contexts", opt_set_target_ns),
587 OPT_BOOLEAN(0, "bootconfig", &probe_conf.bootconfig,
588 "Output probe definition with bootconfig format"),
589 OPT_END()
590 };
591 int ret;
592
593 set_option_flag(options, 'a', "add", PARSE_OPT_EXCLUSIVE);
594 set_option_flag(options, 'd', "del", PARSE_OPT_EXCLUSIVE);
595 set_option_flag(options, 'D', "definition", PARSE_OPT_EXCLUSIVE);
596 set_option_flag(options, 'l', "list", PARSE_OPT_EXCLUSIVE);
597#ifdef HAVE_DWARF_SUPPORT
598 set_option_flag(options, 'L', "line", PARSE_OPT_EXCLUSIVE);
599 set_option_flag(options, 'V', "vars", PARSE_OPT_EXCLUSIVE);
600#else
601# define set_nobuild(s, l, c) set_option_nobuild(options, s, l, "NO_DWARF=1", c)
602 set_nobuild('L', "line", false);
603 set_nobuild('V', "vars", false);
604 set_nobuild('\0', "externs", false);
605 set_nobuild('\0', "range", false);
606 set_nobuild('k', "vmlinux", true);
607 set_nobuild('s', "source", true);
608 set_nobuild('\0', "no-inlines", true);
609# undef set_nobuild
610#endif
611 set_option_flag(options, 'F', "funcs", PARSE_OPT_EXCLUSIVE);
612
613 argc = parse_options(argc, argv, options, probe_usage,
614 PARSE_OPT_STOP_AT_NON_OPTION);
615
616 if (quiet) {
617 if (verbose != 0) {
618 pr_err(" Error: -v and -q are exclusive.\n");
619 return -EINVAL;
620 }
621 verbose = -1;
622 }
623
624 if (argc > 0) {
625 if (strcmp(argv[0], "-") == 0) {
626 usage_with_options_msg(probe_usage, options,
627 "'-' is not supported.\n");
628 }
629 if (params.command && params.command != 'a') {
630 usage_with_options_msg(probe_usage, options,
631 "another command except --add is set.\n");
632 }
633 ret = parse_probe_event_argv(argc, argv);
634 if (ret < 0) {
635 pr_err_with_code(" Error: Command Parse Error.", ret);
636 return ret;
637 }
638 params.command = 'a';
639 }
640
641 ret = symbol__validate_sym_arguments();
642 if (ret)
643 return ret;
644
645 if (probe_conf.max_probes == 0)
646 probe_conf.max_probes = MAX_PROBES;
647
648 /*
649 * Only consider the user's kernel image path if given.
650 */
651 symbol_conf.try_vmlinux_path = (symbol_conf.vmlinux_name == NULL);
652
653 /*
654 * Except for --list, --del and --add, other command doesn't depend
655 * nor change running kernel. So if user gives offline vmlinux,
656 * ignore its buildid.
657 */
658 if (!strchr("lda", params.command) && symbol_conf.vmlinux_name)
659 symbol_conf.ignore_vmlinux_buildid = true;
660
661 switch (params.command) {
662 case 'l':
663 if (params.uprobes) {
664 pr_err(" Error: Don't use --list with --exec.\n");
665 parse_options_usage(probe_usage, options, "l", true);
666 parse_options_usage(NULL, options, "x", true);
667 return -EINVAL;
668 }
669 ret = show_perf_probe_events(params.filter);
670 if (ret < 0)
671 pr_err_with_code(" Error: Failed to show event list.", ret);
672 return ret;
673 case 'F':
674 ret = show_available_funcs(params.target, params.nsi,
675 params.filter, params.uprobes);
676 if (ret < 0)
677 pr_err_with_code(" Error: Failed to show functions.", ret);
678 return ret;
679#ifdef HAVE_DWARF_SUPPORT
680 case 'L':
681 ret = show_line_range(¶ms.line_range, params.target,
682 params.nsi, params.uprobes);
683 if (ret < 0)
684 pr_err_with_code(" Error: Failed to show lines.", ret);
685 return ret;
686 case 'V':
687 if (!params.filter)
688 params.filter = strfilter__new(DEFAULT_VAR_FILTER,
689 NULL);
690
691 ret = show_available_vars(params.events, params.nevents,
692 params.filter);
693 if (ret < 0)
694 pr_err_with_code(" Error: Failed to show vars.", ret);
695 return ret;
696#endif
697 case 'd':
698 ret = perf_del_probe_events(params.filter);
699 if (ret < 0) {
700 pr_err_with_code(" Error: Failed to delete events.", ret);
701 return ret;
702 }
703 break;
704 case 'D':
705 if (probe_conf.bootconfig && params.uprobes) {
706 pr_err(" Error: --bootconfig doesn't support uprobes.\n");
707 return -EINVAL;
708 }
709 __fallthrough;
710 case 'a':
711
712 /* Ensure the last given target is used */
713 if (params.target && !params.target_used) {
714 pr_err(" Error: -x/-m must follow the probe definitions.\n");
715 parse_options_usage(probe_usage, options, "m", true);
716 parse_options_usage(NULL, options, "x", true);
717 return -EINVAL;
718 }
719
720 ret = perf_add_probe_events(params.events, params.nevents);
721 if (ret < 0) {
722
723 /*
724 * When perf_add_probe_events() fails it calls
725 * cleanup_perf_probe_events(pevs, npevs), i.e.
726 * cleanup_perf_probe_events(params.events, params.nevents), which
727 * will call clear_perf_probe_event(), so set nevents to zero
728 * to avoid cleanup_params() to call clear_perf_probe_event() again
729 * on the same pevs.
730 */
731 params.nevents = 0;
732 pr_err_with_code(" Error: Failed to add events.", ret);
733 return ret;
734 }
735 break;
736 default:
737 usage_with_options(probe_usage, options);
738 }
739 return 0;
740}
741
742int cmd_probe(int argc, const char **argv)
743{
744 int ret;
745
746 ret = init_params();
747 if (!ret) {
748 ret = __cmd_probe(argc, argv);
749 cleanup_params();
750 }
751
752 return ret < 0 ? ret : 0;
753}
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 return line_range__init(¶ms.line_range);
310}
311
312static void cleanup_params(void)
313{
314 int i;
315
316 for (i = 0; i < params.nevents; i++)
317 clear_perf_probe_event(params.events + i);
318 line_range__clear(¶ms.line_range);
319 free(params.target);
320 strfilter__delete(params.filter);
321 nsinfo__put(params.nsi);
322 memset(¶ms, 0, sizeof(params));
323}
324
325static void pr_err_with_code(const char *msg, int err)
326{
327 char sbuf[STRERR_BUFSIZE];
328
329 pr_err("%s", msg);
330 pr_debug(" Reason: %s (Code: %d)",
331 str_error_r(-err, sbuf, sizeof(sbuf)), err);
332 pr_err("\n");
333}
334
335static int perf_add_probe_events(struct perf_probe_event *pevs, int npevs)
336{
337 int ret;
338 int i, k;
339 const char *event = NULL, *group = NULL;
340
341 ret = init_probe_symbol_maps(pevs->uprobes);
342 if (ret < 0)
343 return ret;
344
345 ret = convert_perf_probe_events(pevs, npevs);
346 if (ret < 0)
347 goto out_cleanup;
348
349 if (params.command == 'D') { /* it shows definition */
350 if (probe_conf.bootconfig)
351 ret = show_bootconfig_events(pevs, npevs);
352 else
353 ret = show_probe_trace_events(pevs, npevs);
354 goto out_cleanup;
355 }
356
357 ret = apply_perf_probe_events(pevs, npevs);
358 if (ret < 0)
359 goto out_cleanup;
360
361 for (i = k = 0; i < npevs; i++)
362 k += pevs[i].ntevs;
363
364 pr_info("Added new event%s\n", (k > 1) ? "s:" : ":");
365 for (i = 0; i < npevs; i++) {
366 struct perf_probe_event *pev = &pevs[i];
367
368 for (k = 0; k < pev->ntevs; k++) {
369 struct probe_trace_event *tev = &pev->tevs[k];
370 /* Skipped events have no event name */
371 if (!tev->event)
372 continue;
373
374 /* We use tev's name for showing new events */
375 show_perf_probe_event(tev->group, tev->event, pev,
376 tev->point.module, false);
377
378 /* Save the last valid name */
379 event = tev->event;
380 group = tev->group;
381 }
382 }
383
384 /* Note that it is possible to skip all events because of blacklist */
385 if (event) {
386 /* Show how to use the event. */
387 pr_info("\nYou can now use it in all perf tools, such as:\n\n");
388 pr_info("\tperf record -e %s:%s -aR sleep 1\n\n", group, event);
389 }
390
391out_cleanup:
392 cleanup_perf_probe_events(pevs, npevs);
393 exit_probe_symbol_maps();
394 return ret;
395}
396
397static int del_perf_probe_caches(struct strfilter *filter)
398{
399 struct probe_cache *cache;
400 struct strlist *bidlist;
401 struct str_node *nd;
402 int ret;
403
404 bidlist = build_id_cache__list_all(false);
405 if (!bidlist) {
406 ret = -errno;
407 pr_debug("Failed to get buildids: %d\n", ret);
408 return ret ?: -ENOMEM;
409 }
410
411 strlist__for_each_entry(nd, bidlist) {
412 cache = probe_cache__new(nd->s, NULL);
413 if (!cache)
414 continue;
415 if (probe_cache__filter_purge(cache, filter) < 0 ||
416 probe_cache__commit(cache) < 0)
417 pr_warning("Failed to remove entries for %s\n", nd->s);
418 probe_cache__delete(cache);
419 }
420 return 0;
421}
422
423static int perf_del_probe_events(struct strfilter *filter)
424{
425 int ret, ret2, ufd = -1, kfd = -1;
426 char *str = strfilter__string(filter);
427 struct strlist *klist = NULL, *ulist = NULL;
428 struct str_node *ent;
429
430 if (!str)
431 return -EINVAL;
432
433 pr_debug("Delete filter: \'%s\'\n", str);
434
435 if (probe_conf.cache)
436 return del_perf_probe_caches(filter);
437
438 /* Get current event names */
439 ret = probe_file__open_both(&kfd, &ufd, PF_FL_RW);
440 if (ret < 0)
441 goto out;
442
443 klist = strlist__new(NULL, NULL);
444 ulist = strlist__new(NULL, NULL);
445 if (!klist || !ulist) {
446 ret = -ENOMEM;
447 goto out;
448 }
449
450 ret = probe_file__get_events(kfd, filter, klist);
451 if (ret == 0) {
452 strlist__for_each_entry(ent, klist)
453 pr_info("Removed event: %s\n", ent->s);
454
455 ret = probe_file__del_strlist(kfd, klist);
456 if (ret < 0)
457 goto error;
458 } else if (ret == -ENOMEM)
459 goto error;
460
461 ret2 = probe_file__get_events(ufd, filter, ulist);
462 if (ret2 == 0) {
463 strlist__for_each_entry(ent, ulist)
464 pr_info("Removed event: %s\n", ent->s);
465
466 ret2 = probe_file__del_strlist(ufd, ulist);
467 if (ret2 < 0)
468 goto error;
469 } else if (ret2 == -ENOMEM)
470 goto error;
471
472 if (ret == -ENOENT && ret2 == -ENOENT)
473 pr_warning("\"%s\" does not hit any event.\n", str);
474 else
475 ret = 0;
476
477error:
478 if (kfd >= 0)
479 close(kfd);
480 if (ufd >= 0)
481 close(ufd);
482out:
483 strlist__delete(klist);
484 strlist__delete(ulist);
485 free(str);
486
487 return ret;
488}
489
490#ifdef HAVE_DWARF_SUPPORT
491#define PROBEDEF_STR \
492 "[EVENT=]FUNC[@SRC][+OFF|%return|:RL|;PT]|SRC:AL|SRC;PT [[NAME=]ARG ...]"
493#else
494#define PROBEDEF_STR "[EVENT=]FUNC[+OFF|%return] [[NAME=]ARG ...]"
495#endif
496
497
498static int
499__cmd_probe(int argc, const char **argv)
500{
501 const char * const probe_usage[] = {
502 "perf probe [<options>] 'PROBEDEF' ['PROBEDEF' ...]",
503 "perf probe [<options>] --add 'PROBEDEF' [--add 'PROBEDEF' ...]",
504 "perf probe [<options>] --del '[GROUP:]EVENT' ...",
505 "perf probe --list [GROUP:]EVENT ...",
506#ifdef HAVE_DWARF_SUPPORT
507 "perf probe [<options>] --line 'LINEDESC'",
508 "perf probe [<options>] --vars 'PROBEPOINT'",
509#endif
510 "perf probe [<options>] --funcs",
511 NULL
512 };
513 struct option options[] = {
514 OPT_INCR('v', "verbose", &verbose,
515 "be more verbose (show parsed arguments, etc)"),
516 OPT_BOOLEAN('q', "quiet", &quiet,
517 "be quiet (do not show any warnings or messages)"),
518 OPT_CALLBACK_DEFAULT('l', "list", NULL, "[GROUP:]EVENT",
519 "list up probe events",
520 opt_set_filter_with_command, DEFAULT_LIST_FILTER),
521 OPT_CALLBACK('d', "del", NULL, "[GROUP:]EVENT", "delete a probe event.",
522 opt_set_filter_with_command),
523 OPT_CALLBACK('a', "add", NULL, PROBEDEF_STR,
524 "probe point definition, where\n"
525 "\t\tGROUP:\tGroup name (optional)\n"
526 "\t\tEVENT:\tEvent name\n"
527 "\t\tFUNC:\tFunction name\n"
528 "\t\tOFF:\tOffset from function entry (in byte)\n"
529 "\t\t%return:\tPut the probe at function return\n"
530#ifdef HAVE_DWARF_SUPPORT
531 "\t\tSRC:\tSource code path\n"
532 "\t\tRL:\tRelative line number from function entry.\n"
533 "\t\tAL:\tAbsolute line number in file.\n"
534 "\t\tPT:\tLazy expression of line code.\n"
535 "\t\tARG:\tProbe argument (local variable name or\n"
536 "\t\t\tkprobe-tracer argument format.)\n",
537#else
538 "\t\tARG:\tProbe argument (kprobe-tracer argument format.)\n",
539#endif
540 opt_add_probe_event),
541 OPT_CALLBACK('D', "definition", NULL, PROBEDEF_STR,
542 "Show trace event definition of given traceevent for k/uprobe_events.",
543 opt_add_probe_event),
544 OPT_BOOLEAN('f', "force", &probe_conf.force_add, "forcibly add events"
545 " with existing name"),
546 OPT_CALLBACK('L', "line", NULL,
547 "FUNC[:RLN[+NUM|-RLN2]]|SRC:ALN[+NUM|-ALN2]",
548 "Show source code lines.", opt_show_lines),
549 OPT_CALLBACK('V', "vars", NULL,
550 "FUNC[@SRC][+OFF|%return|:RL|;PT]|SRC:AL|SRC;PT",
551 "Show accessible variables on PROBEDEF", opt_show_vars),
552 OPT_BOOLEAN('\0', "externs", &probe_conf.show_ext_vars,
553 "Show external variables too (with --vars only)"),
554 OPT_BOOLEAN('\0', "range", &probe_conf.show_location_range,
555 "Show variables location range in scope (with --vars only)"),
556 OPT_STRING('k', "vmlinux", &symbol_conf.vmlinux_name,
557 "file", "vmlinux pathname"),
558 OPT_STRING('s', "source", &symbol_conf.source_prefix,
559 "directory", "path to kernel source"),
560 OPT_BOOLEAN('\0', "no-inlines", &probe_conf.no_inlines,
561 "Don't search inlined functions"),
562 OPT__DRY_RUN(&probe_event_dry_run),
563 OPT_INTEGER('\0', "max-probes", &probe_conf.max_probes,
564 "Set how many probe points can be found for a probe."),
565 OPT_CALLBACK_DEFAULT('F', "funcs", NULL, "[FILTER]",
566 "Show potential probe-able functions.",
567 opt_set_filter_with_command, DEFAULT_FUNC_FILTER),
568 OPT_CALLBACK('\0', "filter", NULL,
569 "[!]FILTER", "Set a filter (with --vars/funcs only)\n"
570 "\t\t\t(default: \"" DEFAULT_VAR_FILTER "\" for --vars,\n"
571 "\t\t\t \"" DEFAULT_FUNC_FILTER "\" for --funcs)",
572 opt_set_filter),
573 OPT_CALLBACK('x', "exec", NULL, "executable|path",
574 "target executable name or path", opt_set_target),
575 OPT_CALLBACK('m', "module", NULL, "modname|path",
576 "target module name (for online) or path (for offline)",
577 opt_set_target),
578 OPT_BOOLEAN(0, "demangle", &symbol_conf.demangle,
579 "Enable symbol demangling"),
580 OPT_BOOLEAN(0, "demangle-kernel", &symbol_conf.demangle_kernel,
581 "Enable kernel symbol demangling"),
582 OPT_BOOLEAN(0, "cache", &probe_conf.cache, "Manipulate probe cache"),
583 OPT_STRING(0, "symfs", &symbol_conf.symfs, "directory",
584 "Look for files with symbols relative to this directory"),
585 OPT_CALLBACK(0, "target-ns", NULL, "pid",
586 "target pid for namespace contexts", opt_set_target_ns),
587 OPT_BOOLEAN(0, "bootconfig", &probe_conf.bootconfig,
588 "Output probe definition with bootconfig format"),
589 OPT_END()
590 };
591 int ret;
592
593 set_option_flag(options, 'a', "add", PARSE_OPT_EXCLUSIVE);
594 set_option_flag(options, 'd', "del", PARSE_OPT_EXCLUSIVE);
595 set_option_flag(options, 'D', "definition", PARSE_OPT_EXCLUSIVE);
596 set_option_flag(options, 'l', "list", PARSE_OPT_EXCLUSIVE);
597#ifdef HAVE_DWARF_SUPPORT
598 set_option_flag(options, 'L', "line", PARSE_OPT_EXCLUSIVE);
599 set_option_flag(options, 'V', "vars", PARSE_OPT_EXCLUSIVE);
600#else
601# define set_nobuild(s, l, c) set_option_nobuild(options, s, l, "NO_DWARF=1", c)
602 set_nobuild('L', "line", false);
603 set_nobuild('V', "vars", false);
604 set_nobuild('\0', "externs", false);
605 set_nobuild('\0', "range", false);
606 set_nobuild('k', "vmlinux", true);
607 set_nobuild('s', "source", true);
608 set_nobuild('\0', "no-inlines", true);
609# undef set_nobuild
610#endif
611 set_option_flag(options, 'F', "funcs", PARSE_OPT_EXCLUSIVE);
612
613 argc = parse_options(argc, argv, options, probe_usage,
614 PARSE_OPT_STOP_AT_NON_OPTION);
615
616 if (quiet) {
617 if (verbose != 0) {
618 pr_err(" Error: -v and -q are exclusive.\n");
619 return -EINVAL;
620 }
621 verbose = -1;
622 }
623
624 if (argc > 0) {
625 if (strcmp(argv[0], "-") == 0) {
626 usage_with_options_msg(probe_usage, options,
627 "'-' is not supported.\n");
628 }
629 if (params.command && params.command != 'a') {
630 usage_with_options_msg(probe_usage, options,
631 "another command except --add is set.\n");
632 }
633 ret = parse_probe_event_argv(argc, argv);
634 if (ret < 0) {
635 pr_err_with_code(" Error: Command Parse Error.", ret);
636 return ret;
637 }
638 params.command = 'a';
639 }
640
641 ret = symbol__validate_sym_arguments();
642 if (ret)
643 return ret;
644
645 if (probe_conf.max_probes == 0)
646 probe_conf.max_probes = MAX_PROBES;
647
648 /*
649 * Only consider the user's kernel image path if given.
650 */
651 symbol_conf.try_vmlinux_path = (symbol_conf.vmlinux_name == NULL);
652
653 /*
654 * Except for --list, --del and --add, other command doesn't depend
655 * nor change running kernel. So if user gives offline vmlinux,
656 * ignore its buildid.
657 */
658 if (!strchr("lda", params.command) && symbol_conf.vmlinux_name)
659 symbol_conf.ignore_vmlinux_buildid = true;
660
661 switch (params.command) {
662 case 'l':
663 if (params.uprobes) {
664 pr_err(" Error: Don't use --list with --exec.\n");
665 parse_options_usage(probe_usage, options, "l", true);
666 parse_options_usage(NULL, options, "x", true);
667 return -EINVAL;
668 }
669 ret = show_perf_probe_events(params.filter);
670 if (ret < 0)
671 pr_err_with_code(" Error: Failed to show event list.", ret);
672 return ret;
673 case 'F':
674 ret = show_available_funcs(params.target, params.nsi,
675 params.filter, params.uprobes);
676 if (ret < 0)
677 pr_err_with_code(" Error: Failed to show functions.", ret);
678 return ret;
679#ifdef HAVE_DWARF_SUPPORT
680 case 'L':
681 ret = show_line_range(¶ms.line_range, params.target,
682 params.nsi, params.uprobes);
683 if (ret < 0)
684 pr_err_with_code(" Error: Failed to show lines.", ret);
685 return ret;
686 case 'V':
687 if (!params.filter)
688 params.filter = strfilter__new(DEFAULT_VAR_FILTER,
689 NULL);
690
691 ret = show_available_vars(params.events, params.nevents,
692 params.filter);
693 if (ret < 0)
694 pr_err_with_code(" Error: Failed to show vars.", ret);
695 return ret;
696#endif
697 case 'd':
698 ret = perf_del_probe_events(params.filter);
699 if (ret < 0) {
700 pr_err_with_code(" Error: Failed to delete events.", ret);
701 return ret;
702 }
703 break;
704 case 'D':
705 if (probe_conf.bootconfig && params.uprobes) {
706 pr_err(" Error: --bootconfig doesn't support uprobes.\n");
707 return -EINVAL;
708 }
709 __fallthrough;
710 case 'a':
711
712 /* Ensure the last given target is used */
713 if (params.target && !params.target_used) {
714 pr_err(" Error: -x/-m must follow the probe definitions.\n");
715 parse_options_usage(probe_usage, options, "m", true);
716 parse_options_usage(NULL, options, "x", true);
717 return -EINVAL;
718 }
719
720 ret = perf_add_probe_events(params.events, params.nevents);
721 if (ret < 0) {
722
723 /*
724 * When perf_add_probe_events() fails it calls
725 * cleanup_perf_probe_events(pevs, npevs), i.e.
726 * cleanup_perf_probe_events(params.events, params.nevents), which
727 * will call clear_perf_probe_event(), so set nevents to zero
728 * to avoid cleanup_params() to call clear_perf_probe_event() again
729 * on the same pevs.
730 */
731 params.nevents = 0;
732 pr_err_with_code(" Error: Failed to add events.", ret);
733 return ret;
734 }
735 break;
736 default:
737 usage_with_options(probe_usage, options);
738 }
739 return 0;
740}
741
742int cmd_probe(int argc, const char **argv)
743{
744 int ret;
745
746 ret = init_params();
747 if (!ret) {
748 ret = __cmd_probe(argc, argv);
749 cleanup_params();
750 }
751
752 return ret < 0 ? ret : 0;
753}