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.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>
34 #define DEFAULT_VAR_FILTER "!__k???tab_* & !__crc_*"
35 #define DEFAULT_FUNC_FILTER "!_* & !*@plt"
36 #define DEFAULT_LIST_FILTER "*"
38 /* Session management structure */
40 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
);
87 if (!params
->filter
) {
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
);
193 free(params
->target
);
194 params
->target
= tmp
;
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
&& nsinfo__need_setns(nsip
))
220 params
->nsi
= nsinfo__get(nsip
);
230 /* Command option callbacks */
232 #ifdef HAVE_LIBDW_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)
311 params
= calloc(1, sizeof(*params
));
315 ret
= line_range__init(¶ms
->line_range
);
321 static void cleanup_params(void)
325 for (i
= 0; i
< params
->nevents
; i
++)
326 clear_perf_probe_event(params
->events
+ i
);
327 line_range__clear(¶ms
->line_range
);
328 zfree(¶ms
->target
);
329 strfilter__delete(params
->filter
);
330 nsinfo__put(params
->nsi
);
334 static void pr_err_with_code(const char *msg
, int err
)
336 char sbuf
[STRERR_BUFSIZE
];
339 pr_debug(" Reason: %s (Code: %d)",
340 str_error_r(-err
, sbuf
, sizeof(sbuf
)), err
);
344 static int perf_add_probe_events(struct perf_probe_event
*pevs
, int npevs
)
348 const char *event
= NULL
, *group
= NULL
;
350 ret
= init_probe_symbol_maps(pevs
->uprobes
);
354 ret
= convert_perf_probe_events(pevs
, npevs
);
358 if (params
->command
== 'D') { /* it shows definition */
359 if (probe_conf
.bootconfig
)
360 ret
= show_bootconfig_events(pevs
, npevs
);
362 ret
= show_probe_trace_events(pevs
, npevs
);
366 ret
= apply_perf_probe_events(pevs
, npevs
);
370 for (i
= k
= 0; i
< npevs
; i
++)
373 pr_info("Added new event%s\n", (k
> 1) ? "s:" : ":");
374 for (i
= 0; i
< npevs
; i
++) {
375 struct perf_probe_event
*pev
= &pevs
[i
];
377 for (k
= 0; k
< pev
->ntevs
; k
++) {
378 struct probe_trace_event
*tev
= &pev
->tevs
[k
];
379 /* Skipped events have no event name */
383 /* We use tev's name for showing new events */
384 show_perf_probe_event(tev
->group
, tev
->event
, pev
,
385 tev
->point
.module
, false);
387 /* Save the last valid name */
393 /* Note that it is possible to skip all events because of blacklist */
395 #ifndef HAVE_LIBTRACEEVENT
396 pr_info("\nperf is not linked with libtraceevent, to use the new probe you can use tracefs:\n\n");
397 pr_info("\tcd /sys/kernel/tracing/\n");
398 pr_info("\techo 1 > events/%s/%s/enable\n", group
, event
);
399 pr_info("\techo 1 > tracing_on\n");
400 pr_info("\tcat trace_pipe\n");
401 pr_info("\tBefore removing the probe, echo 0 > events/%s/%s/enable\n", group
, event
);
403 /* Show how to use the event. */
404 pr_info("\nYou can now use it in all perf tools, such as:\n\n");
405 pr_info("\tperf record -e %s:%s -aR sleep 1\n\n", group
, event
);
410 cleanup_perf_probe_events(pevs
, npevs
);
411 exit_probe_symbol_maps();
415 static int del_perf_probe_caches(struct strfilter
*filter
)
417 struct probe_cache
*cache
;
418 struct strlist
*bidlist
;
422 bidlist
= build_id_cache__list_all(false);
425 pr_debug("Failed to get buildids: %d\n", ret
);
426 return ret
?: -ENOMEM
;
429 strlist__for_each_entry(nd
, bidlist
) {
430 cache
= probe_cache__new(nd
->s
, NULL
);
433 if (probe_cache__filter_purge(cache
, filter
) < 0 ||
434 probe_cache__commit(cache
) < 0)
435 pr_warning("Failed to remove entries for %s\n", nd
->s
);
436 probe_cache__delete(cache
);
441 static int perf_del_probe_events(struct strfilter
*filter
)
443 int ret
, ret2
, ufd
= -1, kfd
= -1;
444 char *str
= strfilter__string(filter
);
445 struct strlist
*klist
= NULL
, *ulist
= NULL
;
446 struct str_node
*ent
;
451 pr_debug("Delete filter: \'%s\'\n", str
);
453 if (probe_conf
.cache
)
454 return del_perf_probe_caches(filter
);
456 /* Get current event names */
457 ret
= probe_file__open_both(&kfd
, &ufd
, PF_FL_RW
);
461 klist
= strlist__new(NULL
, NULL
);
462 ulist
= strlist__new(NULL
, NULL
);
463 if (!klist
|| !ulist
) {
468 ret
= probe_file__get_events(kfd
, filter
, klist
);
470 strlist__for_each_entry(ent
, klist
)
471 pr_info("Removed event: %s\n", ent
->s
);
473 ret
= probe_file__del_strlist(kfd
, klist
);
476 } else if (ret
== -ENOMEM
)
479 ret2
= probe_file__get_events(ufd
, filter
, ulist
);
481 strlist__for_each_entry(ent
, ulist
)
482 pr_info("Removed event: %s\n", ent
->s
);
484 ret2
= probe_file__del_strlist(ufd
, ulist
);
487 } else if (ret2
== -ENOMEM
)
490 if (ret
== -ENOENT
&& ret2
== -ENOENT
)
491 pr_warning("\"%s\" does not hit any event.\n", str
);
501 strlist__delete(klist
);
502 strlist__delete(ulist
);
508 #ifdef HAVE_LIBDW_SUPPORT
509 #define PROBEDEF_STR \
510 "[EVENT=]FUNC[@SRC][+OFF|%return|:RL|;PT]|SRC:AL|SRC;PT [[NAME=]ARG ...]"
512 #define PROBEDEF_STR "[EVENT=]FUNC[+OFF|%return] [[NAME=]ARG ...]"
517 __cmd_probe(int argc
, const char **argv
)
519 const char * const probe_usage
[] = {
520 "perf probe [<options>] 'PROBEDEF' ['PROBEDEF' ...]",
521 "perf probe [<options>] --add 'PROBEDEF' [--add 'PROBEDEF' ...]",
522 "perf probe [<options>] --del '[GROUP:]EVENT' ...",
523 "perf probe --list [GROUP:]EVENT ...",
524 #ifdef HAVE_LIBDW_SUPPORT
525 "perf probe [<options>] --line 'LINEDESC'",
526 "perf probe [<options>] --vars 'PROBEPOINT'",
528 "perf probe [<options>] --funcs",
531 struct option options
[] = {
532 OPT_INCR('v', "verbose", &verbose
,
533 "be more verbose (show parsed arguments, etc)"),
534 OPT_BOOLEAN('q', "quiet", &quiet
,
535 "be quiet (do not show any warnings or messages)"),
536 OPT_CALLBACK_DEFAULT('l', "list", NULL
, "[GROUP:]EVENT",
537 "list up probe events",
538 opt_set_filter_with_command
, DEFAULT_LIST_FILTER
),
539 OPT_CALLBACK('d', "del", NULL
, "[GROUP:]EVENT", "delete a probe event.",
540 opt_set_filter_with_command
),
541 OPT_CALLBACK('a', "add", NULL
, PROBEDEF_STR
,
542 "probe point definition, where\n"
543 "\t\tGROUP:\tGroup name (optional)\n"
544 "\t\tEVENT:\tEvent name\n"
545 "\t\tFUNC:\tFunction name\n"
546 "\t\tOFF:\tOffset from function entry (in byte)\n"
547 "\t\t%return:\tPut the probe at function return\n"
548 #ifdef HAVE_LIBDW_SUPPORT
549 "\t\tSRC:\tSource code path\n"
550 "\t\tRL:\tRelative line number from function entry.\n"
551 "\t\tAL:\tAbsolute line number in file.\n"
552 "\t\tPT:\tLazy expression of line code.\n"
553 "\t\tARG:\tProbe argument (local variable name or\n"
554 "\t\t\tkprobe-tracer argument format.)\n",
556 "\t\tARG:\tProbe argument (kprobe-tracer argument format.)\n",
558 opt_add_probe_event
),
559 OPT_CALLBACK('D', "definition", NULL
, PROBEDEF_STR
,
560 "Show trace event definition of given traceevent for k/uprobe_events.",
561 opt_add_probe_event
),
562 OPT_BOOLEAN('f', "force", &probe_conf
.force_add
, "forcibly add events"
563 " with existing name"),
564 OPT_CALLBACK('L', "line", NULL
,
565 "FUNC[:RLN[+NUM|-RLN2]]|SRC:ALN[+NUM|-ALN2]",
566 "Show source code lines.", opt_show_lines
),
567 OPT_CALLBACK('V', "vars", NULL
,
568 "FUNC[@SRC][+OFF|%return|:RL|;PT]|SRC:AL|SRC;PT",
569 "Show accessible variables on PROBEDEF", opt_show_vars
),
570 OPT_BOOLEAN('\0', "externs", &probe_conf
.show_ext_vars
,
571 "Show external variables too (with --vars only)"),
572 OPT_BOOLEAN('\0', "range", &probe_conf
.show_location_range
,
573 "Show variables location range in scope (with --vars only)"),
574 OPT_STRING('k', "vmlinux", &symbol_conf
.vmlinux_name
,
575 "file", "vmlinux pathname"),
576 OPT_STRING('s', "source", &symbol_conf
.source_prefix
,
577 "directory", "path to kernel source"),
578 OPT_BOOLEAN('\0', "no-inlines", &probe_conf
.no_inlines
,
579 "Don't search inlined functions"),
580 OPT__DRY_RUN(&probe_event_dry_run
),
581 OPT_INTEGER('\0', "max-probes", &probe_conf
.max_probes
,
582 "Set how many probe points can be found for a probe."),
583 OPT_CALLBACK_DEFAULT('F', "funcs", NULL
, "[FILTER]",
584 "Show potential probe-able functions.",
585 opt_set_filter_with_command
, DEFAULT_FUNC_FILTER
),
586 OPT_CALLBACK('\0', "filter", NULL
,
587 "[!]FILTER", "Set a filter (with --vars/funcs only)\n"
588 "\t\t\t(default: \"" DEFAULT_VAR_FILTER
"\" for --vars,\n"
589 "\t\t\t \"" DEFAULT_FUNC_FILTER
"\" for --funcs)",
591 OPT_CALLBACK('x', "exec", NULL
, "executable|path",
592 "target executable name or path", opt_set_target
),
593 OPT_CALLBACK('m', "module", NULL
, "modname|path",
594 "target module name (for online) or path (for offline)",
596 OPT_BOOLEAN(0, "demangle", &symbol_conf
.demangle
,
597 "Enable symbol demangling"),
598 OPT_BOOLEAN(0, "demangle-kernel", &symbol_conf
.demangle_kernel
,
599 "Enable kernel symbol demangling"),
600 OPT_BOOLEAN(0, "cache", &probe_conf
.cache
, "Manipulate probe cache"),
601 OPT_STRING(0, "symfs", &symbol_conf
.symfs
, "directory",
602 "Look for files with symbols relative to this directory"),
603 OPT_CALLBACK(0, "target-ns", NULL
, "pid",
604 "target pid for namespace contexts", opt_set_target_ns
),
605 OPT_BOOLEAN(0, "bootconfig", &probe_conf
.bootconfig
,
606 "Output probe definition with bootconfig format"),
611 set_option_flag(options
, 'a', "add", PARSE_OPT_EXCLUSIVE
);
612 set_option_flag(options
, 'd', "del", PARSE_OPT_EXCLUSIVE
);
613 set_option_flag(options
, 'D', "definition", PARSE_OPT_EXCLUSIVE
);
614 set_option_flag(options
, 'l', "list", PARSE_OPT_EXCLUSIVE
);
615 #ifdef HAVE_LIBDW_SUPPORT
616 set_option_flag(options
, 'L', "line", PARSE_OPT_EXCLUSIVE
);
617 set_option_flag(options
, 'V', "vars", PARSE_OPT_EXCLUSIVE
);
619 # define set_nobuild(s, l, c) set_option_nobuild(options, s, l, "NO_LIBDW=1", c)
620 set_nobuild('L', "line", false);
621 set_nobuild('V', "vars", false);
622 set_nobuild('\0', "externs", false);
623 set_nobuild('\0', "range", false);
624 set_nobuild('k', "vmlinux", true);
625 set_nobuild('s', "source", true);
626 set_nobuild('\0', "no-inlines", true);
629 set_option_flag(options
, 'F', "funcs", PARSE_OPT_EXCLUSIVE
);
631 argc
= parse_options(argc
, argv
, options
, probe_usage
,
632 PARSE_OPT_STOP_AT_NON_OPTION
);
636 pr_err(" Error: -v and -q are exclusive.\n");
643 if (strcmp(argv
[0], "-") == 0) {
644 usage_with_options_msg(probe_usage
, options
,
645 "'-' is not supported.\n");
647 if (params
->command
&& params
->command
!= 'a') {
648 usage_with_options_msg(probe_usage
, options
,
649 "another command except --add is set.\n");
651 ret
= parse_probe_event_argv(argc
, argv
);
653 pr_err_with_code(" Error: Command Parse Error.", ret
);
656 params
->command
= 'a';
659 ret
= symbol__validate_sym_arguments();
663 if (probe_conf
.max_probes
== 0)
664 probe_conf
.max_probes
= MAX_PROBES
;
667 * Only consider the user's kernel image path if given.
669 symbol_conf
.try_vmlinux_path
= (symbol_conf
.vmlinux_name
== NULL
);
672 * Except for --list, --del and --add, other command doesn't depend
673 * nor change running kernel. So if user gives offline vmlinux,
674 * ignore its buildid.
676 if (!strchr("lda", params
->command
) && symbol_conf
.vmlinux_name
)
677 symbol_conf
.ignore_vmlinux_buildid
= true;
679 switch (params
->command
) {
681 if (params
->uprobes
) {
682 pr_err(" Error: Don't use --list with --exec.\n");
683 parse_options_usage(probe_usage
, options
, "l", true);
684 parse_options_usage(NULL
, options
, "x", true);
687 ret
= show_perf_probe_events(params
->filter
);
689 pr_err_with_code(" Error: Failed to show event list.", ret
);
692 ret
= show_available_funcs(params
->target
, params
->nsi
,
693 params
->filter
, params
->uprobes
);
695 pr_err_with_code(" Error: Failed to show functions.", ret
);
697 #ifdef HAVE_LIBDW_SUPPORT
699 ret
= show_line_range(¶ms
->line_range
, params
->target
,
700 params
->nsi
, params
->uprobes
);
702 pr_err_with_code(" Error: Failed to show lines.", ret
);
706 params
->filter
= strfilter__new(DEFAULT_VAR_FILTER
,
709 ret
= show_available_vars(params
->events
, params
->nevents
,
712 pr_err_with_code(" Error: Failed to show vars.", ret
);
716 ret
= perf_del_probe_events(params
->filter
);
718 pr_err_with_code(" Error: Failed to delete events.", ret
);
723 if (probe_conf
.bootconfig
&& params
->uprobes
) {
724 pr_err(" Error: --bootconfig doesn't support uprobes.\n");
730 /* Ensure the last given target is used */
731 if (params
->target
&& !params
->target_used
) {
732 pr_err(" Error: -x/-m must follow the probe definitions.\n");
733 parse_options_usage(probe_usage
, options
, "m", true);
734 parse_options_usage(NULL
, options
, "x", true);
738 ret
= perf_add_probe_events(params
->events
, params
->nevents
);
742 * When perf_add_probe_events() fails it calls
743 * cleanup_perf_probe_events(pevs, npevs), i.e.
744 * cleanup_perf_probe_events(params->events, params->nevents), which
745 * will call clear_perf_probe_event(), so set nevents to zero
746 * to avoid cleanup_params() to call clear_perf_probe_event() again
750 pr_err_with_code(" Error: Failed to add events.", ret
);
755 usage_with_options(probe_usage
, options
);
760 int cmd_probe(int argc
, const char **argv
)
766 ret
= __cmd_probe(argc
, argv
);
770 return ret
< 0 ? ret
: 0;