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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_conf.h"
25#include "util/debug.h"
26#include <subcmd/parse-options.h>
27#include "util/probe-finder.h"
28#include "util/probe-event.h"
29#include "util/probe-file.h"
30#include <linux/string.h>
31#include <linux/zalloc.h>
32
33#define DEFAULT_VAR_FILTER "!__k???tab_* & !__crc_*"
34#define DEFAULT_FUNC_FILTER "!_*"
35#define DEFAULT_LIST_FILTER "*"
36
37/* Session management structure */
38static struct {
39 int command; /* Command short_name */
40 bool list_events;
41 bool uprobes;
42 bool quiet;
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 && nsip->need_setns)
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 ret = show_probe_trace_events(pevs, npevs);
351 goto out_cleanup;
352 }
353
354 ret = apply_perf_probe_events(pevs, npevs);
355 if (ret < 0)
356 goto out_cleanup;
357
358 for (i = k = 0; i < npevs; i++)
359 k += pevs[i].ntevs;
360
361 pr_info("Added new event%s\n", (k > 1) ? "s:" : ":");
362 for (i = 0; i < npevs; i++) {
363 struct perf_probe_event *pev = &pevs[i];
364
365 for (k = 0; k < pev->ntevs; k++) {
366 struct probe_trace_event *tev = &pev->tevs[k];
367
368 /* We use tev's name for showing new events */
369 show_perf_probe_event(tev->group, tev->event, pev,
370 tev->point.module, false);
371
372 /* Save the last valid name */
373 event = tev->event;
374 group = tev->group;
375 }
376 }
377
378 /* Note that it is possible to skip all events because of blacklist */
379 if (event) {
380 /* Show how to use the event. */
381 pr_info("\nYou can now use it in all perf tools, such as:\n\n");
382 pr_info("\tperf record -e %s:%s -aR sleep 1\n\n", group, event);
383 }
384
385out_cleanup:
386 cleanup_perf_probe_events(pevs, npevs);
387 exit_probe_symbol_maps();
388 return ret;
389}
390
391static int del_perf_probe_caches(struct strfilter *filter)
392{
393 struct probe_cache *cache;
394 struct strlist *bidlist;
395 struct str_node *nd;
396 int ret;
397
398 bidlist = build_id_cache__list_all(false);
399 if (!bidlist) {
400 ret = -errno;
401 pr_debug("Failed to get buildids: %d\n", ret);
402 return ret ?: -ENOMEM;
403 }
404
405 strlist__for_each_entry(nd, bidlist) {
406 cache = probe_cache__new(nd->s, NULL);
407 if (!cache)
408 continue;
409 if (probe_cache__filter_purge(cache, filter) < 0 ||
410 probe_cache__commit(cache) < 0)
411 pr_warning("Failed to remove entries for %s\n", nd->s);
412 probe_cache__delete(cache);
413 }
414 return 0;
415}
416
417static int perf_del_probe_events(struct strfilter *filter)
418{
419 int ret, ret2, ufd = -1, kfd = -1;
420 char *str = strfilter__string(filter);
421 struct strlist *klist = NULL, *ulist = NULL;
422 struct str_node *ent;
423
424 if (!str)
425 return -EINVAL;
426
427 pr_debug("Delete filter: \'%s\'\n", str);
428
429 if (probe_conf.cache)
430 return del_perf_probe_caches(filter);
431
432 /* Get current event names */
433 ret = probe_file__open_both(&kfd, &ufd, PF_FL_RW);
434 if (ret < 0)
435 goto out;
436
437 klist = strlist__new(NULL, NULL);
438 ulist = strlist__new(NULL, NULL);
439 if (!klist || !ulist) {
440 ret = -ENOMEM;
441 goto out;
442 }
443
444 ret = probe_file__get_events(kfd, filter, klist);
445 if (ret == 0) {
446 strlist__for_each_entry(ent, klist)
447 pr_info("Removed event: %s\n", ent->s);
448
449 ret = probe_file__del_strlist(kfd, klist);
450 if (ret < 0)
451 goto error;
452 }
453
454 ret2 = probe_file__get_events(ufd, filter, ulist);
455 if (ret2 == 0) {
456 strlist__for_each_entry(ent, ulist)
457 pr_info("Removed event: %s\n", ent->s);
458
459 ret2 = probe_file__del_strlist(ufd, ulist);
460 if (ret2 < 0)
461 goto error;
462 }
463
464 if (ret == -ENOENT && ret2 == -ENOENT)
465 pr_warning("\"%s\" does not hit any event.\n", str);
466 else
467 ret = 0;
468
469error:
470 if (kfd >= 0)
471 close(kfd);
472 if (ufd >= 0)
473 close(ufd);
474out:
475 strlist__delete(klist);
476 strlist__delete(ulist);
477 free(str);
478
479 return ret;
480}
481
482#ifdef HAVE_DWARF_SUPPORT
483#define PROBEDEF_STR \
484 "[EVENT=]FUNC[@SRC][+OFF|%return|:RL|;PT]|SRC:AL|SRC;PT [[NAME=]ARG ...]"
485#else
486#define PROBEDEF_STR "[EVENT=]FUNC[+OFF|%return] [[NAME=]ARG ...]"
487#endif
488
489
490static int
491__cmd_probe(int argc, const char **argv)
492{
493 const char * const probe_usage[] = {
494 "perf probe [<options>] 'PROBEDEF' ['PROBEDEF' ...]",
495 "perf probe [<options>] --add 'PROBEDEF' [--add 'PROBEDEF' ...]",
496 "perf probe [<options>] --del '[GROUP:]EVENT' ...",
497 "perf probe --list [GROUP:]EVENT ...",
498#ifdef HAVE_DWARF_SUPPORT
499 "perf probe [<options>] --line 'LINEDESC'",
500 "perf probe [<options>] --vars 'PROBEPOINT'",
501#endif
502 "perf probe [<options>] --funcs",
503 NULL
504 };
505 struct option options[] = {
506 OPT_INCR('v', "verbose", &verbose,
507 "be more verbose (show parsed arguments, etc)"),
508 OPT_BOOLEAN('q', "quiet", ¶ms.quiet,
509 "be quiet (do not show any messages)"),
510 OPT_CALLBACK_DEFAULT('l', "list", NULL, "[GROUP:]EVENT",
511 "list up probe events",
512 opt_set_filter_with_command, DEFAULT_LIST_FILTER),
513 OPT_CALLBACK('d', "del", NULL, "[GROUP:]EVENT", "delete a probe event.",
514 opt_set_filter_with_command),
515 OPT_CALLBACK('a', "add", NULL, PROBEDEF_STR,
516 "probe point definition, where\n"
517 "\t\tGROUP:\tGroup name (optional)\n"
518 "\t\tEVENT:\tEvent name\n"
519 "\t\tFUNC:\tFunction name\n"
520 "\t\tOFF:\tOffset from function entry (in byte)\n"
521 "\t\t%return:\tPut the probe at function return\n"
522#ifdef HAVE_DWARF_SUPPORT
523 "\t\tSRC:\tSource code path\n"
524 "\t\tRL:\tRelative line number from function entry.\n"
525 "\t\tAL:\tAbsolute line number in file.\n"
526 "\t\tPT:\tLazy expression of line code.\n"
527 "\t\tARG:\tProbe argument (local variable name or\n"
528 "\t\t\tkprobe-tracer argument format.)\n",
529#else
530 "\t\tARG:\tProbe argument (kprobe-tracer argument format.)\n",
531#endif
532 opt_add_probe_event),
533 OPT_CALLBACK('D', "definition", NULL, PROBEDEF_STR,
534 "Show trace event definition of given traceevent for k/uprobe_events.",
535 opt_add_probe_event),
536 OPT_BOOLEAN('f', "force", &probe_conf.force_add, "forcibly add events"
537 " with existing name"),
538 OPT_CALLBACK('L', "line", NULL,
539 "FUNC[:RLN[+NUM|-RLN2]]|SRC:ALN[+NUM|-ALN2]",
540 "Show source code lines.", opt_show_lines),
541 OPT_CALLBACK('V', "vars", NULL,
542 "FUNC[@SRC][+OFF|%return|:RL|;PT]|SRC:AL|SRC;PT",
543 "Show accessible variables on PROBEDEF", opt_show_vars),
544 OPT_BOOLEAN('\0', "externs", &probe_conf.show_ext_vars,
545 "Show external variables too (with --vars only)"),
546 OPT_BOOLEAN('\0', "range", &probe_conf.show_location_range,
547 "Show variables location range in scope (with --vars only)"),
548 OPT_STRING('k', "vmlinux", &symbol_conf.vmlinux_name,
549 "file", "vmlinux pathname"),
550 OPT_STRING('s', "source", &symbol_conf.source_prefix,
551 "directory", "path to kernel source"),
552 OPT_BOOLEAN('\0', "no-inlines", &probe_conf.no_inlines,
553 "Don't search inlined functions"),
554 OPT__DRY_RUN(&probe_event_dry_run),
555 OPT_INTEGER('\0', "max-probes", &probe_conf.max_probes,
556 "Set how many probe points can be found for a probe."),
557 OPT_CALLBACK_DEFAULT('F', "funcs", NULL, "[FILTER]",
558 "Show potential probe-able functions.",
559 opt_set_filter_with_command, DEFAULT_FUNC_FILTER),
560 OPT_CALLBACK('\0', "filter", NULL,
561 "[!]FILTER", "Set a filter (with --vars/funcs only)\n"
562 "\t\t\t(default: \"" DEFAULT_VAR_FILTER "\" for --vars,\n"
563 "\t\t\t \"" DEFAULT_FUNC_FILTER "\" for --funcs)",
564 opt_set_filter),
565 OPT_CALLBACK('x', "exec", NULL, "executable|path",
566 "target executable name or path", opt_set_target),
567 OPT_CALLBACK('m', "module", NULL, "modname|path",
568 "target module name (for online) or path (for offline)",
569 opt_set_target),
570 OPT_BOOLEAN(0, "demangle", &symbol_conf.demangle,
571 "Enable symbol demangling"),
572 OPT_BOOLEAN(0, "demangle-kernel", &symbol_conf.demangle_kernel,
573 "Enable kernel symbol demangling"),
574 OPT_BOOLEAN(0, "cache", &probe_conf.cache, "Manipulate probe cache"),
575 OPT_STRING(0, "symfs", &symbol_conf.symfs, "directory",
576 "Look for files with symbols relative to this directory"),
577 OPT_CALLBACK(0, "target-ns", NULL, "pid",
578 "target pid for namespace contexts", opt_set_target_ns),
579 OPT_END()
580 };
581 int ret;
582
583 set_option_flag(options, 'a', "add", PARSE_OPT_EXCLUSIVE);
584 set_option_flag(options, 'd', "del", PARSE_OPT_EXCLUSIVE);
585 set_option_flag(options, 'D', "definition", PARSE_OPT_EXCLUSIVE);
586 set_option_flag(options, 'l', "list", PARSE_OPT_EXCLUSIVE);
587#ifdef HAVE_DWARF_SUPPORT
588 set_option_flag(options, 'L', "line", PARSE_OPT_EXCLUSIVE);
589 set_option_flag(options, 'V', "vars", PARSE_OPT_EXCLUSIVE);
590#else
591# define set_nobuild(s, l, c) set_option_nobuild(options, s, l, "NO_DWARF=1", c)
592 set_nobuild('L', "line", false);
593 set_nobuild('V', "vars", false);
594 set_nobuild('\0', "externs", false);
595 set_nobuild('\0', "range", false);
596 set_nobuild('k', "vmlinux", true);
597 set_nobuild('s', "source", true);
598 set_nobuild('\0', "no-inlines", true);
599# undef set_nobuild
600#endif
601 set_option_flag(options, 'F', "funcs", PARSE_OPT_EXCLUSIVE);
602
603 argc = parse_options(argc, argv, options, probe_usage,
604 PARSE_OPT_STOP_AT_NON_OPTION);
605 if (argc > 0) {
606 if (strcmp(argv[0], "-") == 0) {
607 usage_with_options_msg(probe_usage, options,
608 "'-' is not supported.\n");
609 }
610 if (params.command && params.command != 'a') {
611 usage_with_options_msg(probe_usage, options,
612 "another command except --add is set.\n");
613 }
614 ret = parse_probe_event_argv(argc, argv);
615 if (ret < 0) {
616 pr_err_with_code(" Error: Command Parse Error.", ret);
617 return ret;
618 }
619 params.command = 'a';
620 }
621
622 if (params.quiet) {
623 if (verbose != 0) {
624 pr_err(" Error: -v and -q are exclusive.\n");
625 return -EINVAL;
626 }
627 verbose = -1;
628 }
629
630 if (probe_conf.max_probes == 0)
631 probe_conf.max_probes = MAX_PROBES;
632
633 /*
634 * Only consider the user's kernel image path if given.
635 */
636 symbol_conf.try_vmlinux_path = (symbol_conf.vmlinux_name == NULL);
637
638 /*
639 * Except for --list, --del and --add, other command doesn't depend
640 * nor change running kernel. So if user gives offline vmlinux,
641 * ignore its buildid.
642 */
643 if (!strchr("lda", params.command) && symbol_conf.vmlinux_name)
644 symbol_conf.ignore_vmlinux_buildid = true;
645
646 switch (params.command) {
647 case 'l':
648 if (params.uprobes) {
649 pr_err(" Error: Don't use --list with --exec.\n");
650 parse_options_usage(probe_usage, options, "l", true);
651 parse_options_usage(NULL, options, "x", true);
652 return -EINVAL;
653 }
654 ret = show_perf_probe_events(params.filter);
655 if (ret < 0)
656 pr_err_with_code(" Error: Failed to show event list.", ret);
657 return ret;
658 case 'F':
659 ret = show_available_funcs(params.target, params.nsi,
660 params.filter, params.uprobes);
661 if (ret < 0)
662 pr_err_with_code(" Error: Failed to show functions.", ret);
663 return ret;
664#ifdef HAVE_DWARF_SUPPORT
665 case 'L':
666 ret = show_line_range(¶ms.line_range, params.target,
667 params.nsi, params.uprobes);
668 if (ret < 0)
669 pr_err_with_code(" Error: Failed to show lines.", ret);
670 return ret;
671 case 'V':
672 if (!params.filter)
673 params.filter = strfilter__new(DEFAULT_VAR_FILTER,
674 NULL);
675
676 ret = show_available_vars(params.events, params.nevents,
677 params.filter);
678 if (ret < 0)
679 pr_err_with_code(" Error: Failed to show vars.", ret);
680 return ret;
681#endif
682 case 'd':
683 ret = perf_del_probe_events(params.filter);
684 if (ret < 0) {
685 pr_err_with_code(" Error: Failed to delete events.", ret);
686 return ret;
687 }
688 break;
689 case 'D':
690 case 'a':
691
692 /* Ensure the last given target is used */
693 if (params.target && !params.target_used) {
694 pr_err(" Error: -x/-m must follow the probe definitions.\n");
695 parse_options_usage(probe_usage, options, "m", true);
696 parse_options_usage(NULL, options, "x", true);
697 return -EINVAL;
698 }
699
700 ret = perf_add_probe_events(params.events, params.nevents);
701 if (ret < 0) {
702
703 /*
704 * When perf_add_probe_events() fails it calls
705 * cleanup_perf_probe_events(pevs, npevs), i.e.
706 * cleanup_perf_probe_events(params.events, params.nevents), which
707 * will call clear_perf_probe_event(), so set nevents to zero
708 * to avoid cleanup_params() to call clear_perf_probe_event() again
709 * on the same pevs.
710 */
711 params.nevents = 0;
712 pr_err_with_code(" Error: Failed to add events.", ret);
713 return ret;
714 }
715 break;
716 default:
717 usage_with_options(probe_usage, options);
718 }
719 return 0;
720}
721
722int cmd_probe(int argc, const char **argv)
723{
724 int ret;
725
726 ret = init_params();
727 if (!ret) {
728 ret = __cmd_probe(argc, argv);
729 cleanup_params();
730 }
731
732 return ret < 0 ? ret : 0;
733}
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}