1 // SPDX-License-Identifier: GPL-2.0-or-later
5 * Builtin probe command: Set up probe events by C expression
7 * Written by Masami Hiramatsu <mhiramat@redhat.com>
9 #include <sys/utsname.h>
10 #include <sys/types.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>
33 #define DEFAULT_VAR_FILTER "!__k???tab_* & !__crc_*"
34 #define DEFAULT_FUNC_FILTER "!_*"
35 #define DEFAULT_LIST_FILTER "*"
37 /* Session management structure */
39 int command; /* Command short_name */
45 struct perf_probe_event events[MAX_PROBES];
46 struct line_range line_range;
48 struct strfilter *filter;
52 /* Parse an event definition. Note that any error must die. */
53 static int parse_probe_event(const char *str)
55 struct perf_probe_event *pev = ¶ms.events[params.nevents];
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);
64 pev->uprobes = params.uprobes;
66 pev->target = strdup(params.target);
69 params.target_used = true;
72 pev->nsi = nsinfo__get(params.nsi);
74 /* Parse a perf-probe command into event */
75 ret = parse_perf_probe_command(str, pev);
76 pr_debug("%d arguments\n", pev->nargs);
81 static int params_add_filter(const char *str)
83 const char *err = NULL;
86 pr_debug2("Add filter: %s\n", str);
88 params.filter = strfilter__new(str, &err);
90 ret = err ? -EINVAL : -ENOMEM;
92 ret = strfilter__or(params.filter, str, &err);
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), '^');
103 static int set_target(const char *ptr)
109 * The first argument after options can be an absolute path
110 * to an executable / library or kernel module.
112 * TODO: Support relative path, and $PATH, $LD_LIBRARY_PATH,
115 if (!params.target && ptr && *ptr == '/') {
116 params.target = strdup(ptr);
119 params.target_used = false;
122 buf = ptr + (strlen(ptr) - 3);
124 if (strcmp(buf, ".ko"))
125 params.uprobes = true;
132 static int parse_probe_event_argv(int argc, const char **argv)
134 int i, len, ret, found_target;
137 found_target = set_target(argv[0]);
138 if (found_target < 0)
141 if (found_target && argc == 1)
144 /* Bind up rest arguments */
146 for (i = 0; i < argc; i++) {
147 if (i == 0 && found_target)
150 len += strlen(argv[i]) + 1;
152 buf = zalloc(len + 1);
156 for (i = 0; i < argc; i++) {
157 if (i == 0 && found_target)
160 len += sprintf(&buf[len], "%s ", argv[i]);
162 ret = parse_probe_event(buf);
167 static int opt_set_target(const struct option *opt, const char *str,
168 int unset __maybe_unused)
174 if (!strcmp(opt->long_name, "exec"))
175 params.uprobes = true;
176 else if (!strcmp(opt->long_name, "module"))
177 params.uprobes = false;
181 /* Expand given path to absolute path, except for modulename */
182 if (params.uprobes || strchr(str, '/')) {
183 tmp = nsinfo__realpath(str, params.nsi);
185 pr_warning("Failed to get the absolute path of %s: %m\n", str);
195 params.target_used = false;
202 static int opt_set_target_ns(const struct option *opt __maybe_unused,
203 const char *str, int unset __maybe_unused)
211 ns_pid = (pid_t)strtol(str, NULL, 10);
214 pr_warning("Failed to parse %s as a pid: %s\n", str,
218 nsip = nsinfo__new(ns_pid);
219 if (nsip && nsip->need_setns)
220 params.nsi = nsinfo__get(nsip);
230 /* Command option callbacks */
232 #ifdef HAVE_DWARF_SUPPORT
233 static int opt_show_lines(const struct option *opt,
234 const char *str, int unset __maybe_unused)
241 if (params.command == 'L') {
242 pr_warning("Warning: more than one --line options are"
243 " detected. Only the first one is valid.\n");
247 params.command = opt->short_name;
248 ret = parse_line_range_desc(str, ¶ms.line_range);
253 static int opt_show_vars(const struct option *opt,
254 const char *str, int unset __maybe_unused)
256 struct perf_probe_event *pev = ¶ms.events[params.nevents];
262 ret = parse_probe_event(str);
263 if (!ret && pev->nargs != 0) {
264 pr_err(" Error: '--vars' doesn't accept arguments.\n");
267 params.command = opt->short_name;
272 # define opt_show_lines NULL
273 # define opt_show_vars NULL
275 static int opt_add_probe_event(const struct option *opt,
276 const char *str, int unset __maybe_unused)
279 params.command = opt->short_name;
280 return parse_probe_event(str);
286 static int opt_set_filter_with_command(const struct option *opt,
287 const char *str, int unset)
290 params.command = opt->short_name;
293 return params_add_filter(str);
298 static int opt_set_filter(const struct option *opt __maybe_unused,
299 const char *str, int unset __maybe_unused)
302 return params_add_filter(str);
307 static int init_params(void)
309 return line_range__init(¶ms.line_range);
312 static void cleanup_params(void)
316 for (i = 0; i < params.nevents; i++)
317 clear_perf_probe_event(params.events + i);
318 line_range__clear(¶ms.line_range);
320 strfilter__delete(params.filter);
321 nsinfo__put(params.nsi);
322 memset(¶ms, 0, sizeof(params));
325 static void pr_err_with_code(const char *msg, int err)
327 char sbuf[STRERR_BUFSIZE];
330 pr_debug(" Reason: %s (Code: %d)",
331 str_error_r(-err, sbuf, sizeof(sbuf)), err);
335 static int perf_add_probe_events(struct perf_probe_event *pevs, int npevs)
339 const char *event = NULL, *group = NULL;
341 ret = init_probe_symbol_maps(pevs->uprobes);
345 ret = convert_perf_probe_events(pevs, npevs);
349 if (params.command == 'D') { /* it shows definition */
350 ret = show_probe_trace_events(pevs, npevs);
354 ret = apply_perf_probe_events(pevs, npevs);
358 for (i = k = 0; i < npevs; i++)
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];
365 for (k = 0; k < pev->ntevs; k++) {
366 struct probe_trace_event *tev = &pev->tevs[k];
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);
372 /* Save the last valid name */
378 /* Note that it is possible to skip all events because of blacklist */
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);
386 cleanup_perf_probe_events(pevs, npevs);
387 exit_probe_symbol_maps();
391 static int del_perf_probe_caches(struct strfilter *filter)
393 struct probe_cache *cache;
394 struct strlist *bidlist;
398 bidlist = build_id_cache__list_all(false);
401 pr_debug("Failed to get buildids: %d\n", ret);
402 return ret ?: -ENOMEM;
405 strlist__for_each_entry(nd, bidlist) {
406 cache = probe_cache__new(nd->s, NULL);
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);
417 static int perf_del_probe_events(struct strfilter *filter)
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;
427 pr_debug("Delete filter: \'%s\'\n", str);
429 if (probe_conf.cache)
430 return del_perf_probe_caches(filter);
432 /* Get current event names */
433 ret = probe_file__open_both(&kfd, &ufd, PF_FL_RW);
437 klist = strlist__new(NULL, NULL);
438 ulist = strlist__new(NULL, NULL);
439 if (!klist || !ulist) {
444 ret = probe_file__get_events(kfd, filter, klist);
446 strlist__for_each_entry(ent, klist)
447 pr_info("Removed event: %s\n", ent->s);
449 ret = probe_file__del_strlist(kfd, klist);
452 } else if (ret == -ENOMEM)
455 ret2 = probe_file__get_events(ufd, filter, ulist);
457 strlist__for_each_entry(ent, ulist)
458 pr_info("Removed event: %s\n", ent->s);
460 ret2 = probe_file__del_strlist(ufd, ulist);
463 } else if (ret2 == -ENOMEM)
466 if (ret == -ENOENT && ret2 == -ENOENT)
467 pr_warning("\"%s\" does not hit any event.\n", str);
477 strlist__delete(klist);
478 strlist__delete(ulist);
484 #ifdef HAVE_DWARF_SUPPORT
485 #define PROBEDEF_STR \
486 "[EVENT=]FUNC[@SRC][+OFF|%return|:RL|;PT]|SRC:AL|SRC;PT [[NAME=]ARG ...]"
488 #define PROBEDEF_STR "[EVENT=]FUNC[+OFF|%return] [[NAME=]ARG ...]"
493 __cmd_probe(int argc, const char **argv)
495 const char * const probe_usage[] = {
496 "perf probe [<options>] 'PROBEDEF' ['PROBEDEF' ...]",
497 "perf probe [<options>] --add 'PROBEDEF' [--add 'PROBEDEF' ...]",
498 "perf probe [<options>] --del '[GROUP:]EVENT' ...",
499 "perf probe --list [GROUP:]EVENT ...",
500 #ifdef HAVE_DWARF_SUPPORT
501 "perf probe [<options>] --line 'LINEDESC'",
502 "perf probe [<options>] --vars 'PROBEPOINT'",
504 "perf probe [<options>] --funcs",
507 struct option options[] = {
508 OPT_INCR('v', "verbose", &verbose,
509 "be more verbose (show parsed arguments, etc)"),
510 OPT_BOOLEAN('q', "quiet", ¶ms.quiet,
511 "be quiet (do not show any messages)"),
512 OPT_CALLBACK_DEFAULT('l', "list", NULL, "[GROUP:]EVENT",
513 "list up probe events",
514 opt_set_filter_with_command, DEFAULT_LIST_FILTER),
515 OPT_CALLBACK('d', "del", NULL, "[GROUP:]EVENT", "delete a probe event.",
516 opt_set_filter_with_command),
517 OPT_CALLBACK('a', "add", NULL, PROBEDEF_STR,
518 "probe point definition, where\n"
519 "\t\tGROUP:\tGroup name (optional)\n"
520 "\t\tEVENT:\tEvent name\n"
521 "\t\tFUNC:\tFunction name\n"
522 "\t\tOFF:\tOffset from function entry (in byte)\n"
523 "\t\t%return:\tPut the probe at function return\n"
524 #ifdef HAVE_DWARF_SUPPORT
525 "\t\tSRC:\tSource code path\n"
526 "\t\tRL:\tRelative line number from function entry.\n"
527 "\t\tAL:\tAbsolute line number in file.\n"
528 "\t\tPT:\tLazy expression of line code.\n"
529 "\t\tARG:\tProbe argument (local variable name or\n"
530 "\t\t\tkprobe-tracer argument format.)\n",
532 "\t\tARG:\tProbe argument (kprobe-tracer argument format.)\n",
534 opt_add_probe_event),
535 OPT_CALLBACK('D', "definition", NULL, PROBEDEF_STR,
536 "Show trace event definition of given traceevent for k/uprobe_events.",
537 opt_add_probe_event),
538 OPT_BOOLEAN('f', "force", &probe_conf.force_add, "forcibly add events"
539 " with existing name"),
540 OPT_CALLBACK('L', "line", NULL,
541 "FUNC[:RLN[+NUM|-RLN2]]|SRC:ALN[+NUM|-ALN2]",
542 "Show source code lines.", opt_show_lines),
543 OPT_CALLBACK('V', "vars", NULL,
544 "FUNC[@SRC][+OFF|%return|:RL|;PT]|SRC:AL|SRC;PT",
545 "Show accessible variables on PROBEDEF", opt_show_vars),
546 OPT_BOOLEAN('\0', "externs", &probe_conf.show_ext_vars,
547 "Show external variables too (with --vars only)"),
548 OPT_BOOLEAN('\0', "range", &probe_conf.show_location_range,
549 "Show variables location range in scope (with --vars only)"),
550 OPT_STRING('k', "vmlinux", &symbol_conf.vmlinux_name,
551 "file", "vmlinux pathname"),
552 OPT_STRING('s', "source", &symbol_conf.source_prefix,
553 "directory", "path to kernel source"),
554 OPT_BOOLEAN('\0', "no-inlines", &probe_conf.no_inlines,
555 "Don't search inlined functions"),
556 OPT__DRY_RUN(&probe_event_dry_run),
557 OPT_INTEGER('\0', "max-probes", &probe_conf.max_probes,
558 "Set how many probe points can be found for a probe."),
559 OPT_CALLBACK_DEFAULT('F', "funcs", NULL, "[FILTER]",
560 "Show potential probe-able functions.",
561 opt_set_filter_with_command, DEFAULT_FUNC_FILTER),
562 OPT_CALLBACK('\0', "filter", NULL,
563 "[!]FILTER", "Set a filter (with --vars/funcs only)\n"
564 "\t\t\t(default: \"" DEFAULT_VAR_FILTER "\" for --vars,\n"
565 "\t\t\t \"" DEFAULT_FUNC_FILTER "\" for --funcs)",
567 OPT_CALLBACK('x', "exec", NULL, "executable|path",
568 "target executable name or path", opt_set_target),
569 OPT_CALLBACK('m', "module", NULL, "modname|path",
570 "target module name (for online) or path (for offline)",
572 OPT_BOOLEAN(0, "demangle", &symbol_conf.demangle,
573 "Enable symbol demangling"),
574 OPT_BOOLEAN(0, "demangle-kernel", &symbol_conf.demangle_kernel,
575 "Enable kernel symbol demangling"),
576 OPT_BOOLEAN(0, "cache", &probe_conf.cache, "Manipulate probe cache"),
577 OPT_STRING(0, "symfs", &symbol_conf.symfs, "directory",
578 "Look for files with symbols relative to this directory"),
579 OPT_CALLBACK(0, "target-ns", NULL, "pid",
580 "target pid for namespace contexts", opt_set_target_ns),
585 set_option_flag(options, 'a', "add", PARSE_OPT_EXCLUSIVE);
586 set_option_flag(options, 'd', "del", PARSE_OPT_EXCLUSIVE);
587 set_option_flag(options, 'D', "definition", PARSE_OPT_EXCLUSIVE);
588 set_option_flag(options, 'l', "list", PARSE_OPT_EXCLUSIVE);
589 #ifdef HAVE_DWARF_SUPPORT
590 set_option_flag(options, 'L', "line", PARSE_OPT_EXCLUSIVE);
591 set_option_flag(options, 'V', "vars", PARSE_OPT_EXCLUSIVE);
593 # define set_nobuild(s, l, c) set_option_nobuild(options, s, l, "NO_DWARF=1", c)
594 set_nobuild('L', "line", false);
595 set_nobuild('V', "vars", false);
596 set_nobuild('\0', "externs", false);
597 set_nobuild('\0', "range", false);
598 set_nobuild('k', "vmlinux", true);
599 set_nobuild('s', "source", true);
600 set_nobuild('\0', "no-inlines", true);
603 set_option_flag(options, 'F', "funcs", PARSE_OPT_EXCLUSIVE);
605 argc = parse_options(argc, argv, options, probe_usage,
606 PARSE_OPT_STOP_AT_NON_OPTION);
608 if (strcmp(argv[0], "-") == 0) {
609 usage_with_options_msg(probe_usage, options,
610 "'-' is not supported.\n");
612 if (params.command && params.command != 'a') {
613 usage_with_options_msg(probe_usage, options,
614 "another command except --add is set.\n");
616 ret = parse_probe_event_argv(argc, argv);
618 pr_err_with_code(" Error: Command Parse Error.", ret);
621 params.command = 'a';
626 pr_err(" Error: -v and -q are exclusive.\n");
632 if (probe_conf.max_probes == 0)
633 probe_conf.max_probes = MAX_PROBES;
636 * Only consider the user's kernel image path if given.
638 symbol_conf.try_vmlinux_path = (symbol_conf.vmlinux_name == NULL);
641 * Except for --list, --del and --add, other command doesn't depend
642 * nor change running kernel. So if user gives offline vmlinux,
643 * ignore its buildid.
645 if (!strchr("lda", params.command) && symbol_conf.vmlinux_name)
646 symbol_conf.ignore_vmlinux_buildid = true;
648 switch (params.command) {
650 if (params.uprobes) {
651 pr_err(" Error: Don't use --list with --exec.\n");
652 parse_options_usage(probe_usage, options, "l", true);
653 parse_options_usage(NULL, options, "x", true);
656 ret = show_perf_probe_events(params.filter);
658 pr_err_with_code(" Error: Failed to show event list.", ret);
661 ret = show_available_funcs(params.target, params.nsi,
662 params.filter, params.uprobes);
664 pr_err_with_code(" Error: Failed to show functions.", ret);
666 #ifdef HAVE_DWARF_SUPPORT
668 ret = show_line_range(¶ms.line_range, params.target,
669 params.nsi, params.uprobes);
671 pr_err_with_code(" Error: Failed to show lines.", ret);
675 params.filter = strfilter__new(DEFAULT_VAR_FILTER,
678 ret = show_available_vars(params.events, params.nevents,
681 pr_err_with_code(" Error: Failed to show vars.", ret);
685 ret = perf_del_probe_events(params.filter);
687 pr_err_with_code(" Error: Failed to delete events.", ret);
694 /* Ensure the last given target is used */
695 if (params.target && !params.target_used) {
696 pr_err(" Error: -x/-m must follow the probe definitions.\n");
697 parse_options_usage(probe_usage, options, "m", true);
698 parse_options_usage(NULL, options, "x", true);
702 ret = perf_add_probe_events(params.events, params.nevents);
706 * When perf_add_probe_events() fails it calls
707 * cleanup_perf_probe_events(pevs, npevs), i.e.
708 * cleanup_perf_probe_events(params.events, params.nevents), which
709 * will call clear_perf_probe_event(), so set nevents to zero
710 * to avoid cleanup_params() to call clear_perf_probe_event() again
714 pr_err_with_code(" Error: Failed to add events.", ret);
719 usage_with_options(probe_usage, options);
724 int cmd_probe(int argc, const char **argv)
730 ret = __cmd_probe(argc, argv);
734 return ret < 0 ? ret : 0;