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 = &params.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, &params.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 = &params.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(&params.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(&params.line_range);
319	free(params.target);
320	strfilter__delete(params.filter);
321	nsinfo__put(params.nsi);
322	memset(&params, 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(&params.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 = &params->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_LIBDW_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, &params->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 = &params->events[params->nevents];
257	int ret;
258
259	if (!str)
260		return 0;
261
262	ret = parse_probe_event(str);
263	if (!ret && pev->nargs != 0) {
264		pr_err("  Error: '--vars' doesn't accept arguments.\n");
265		return -EINVAL;
266	}
267	params->command = opt->short_name;
268
269	return ret;
270}
271#else
272# define opt_show_lines NULL
273# define opt_show_vars NULL
274#endif
275static int opt_add_probe_event(const struct option *opt,
276			      const char *str, int unset __maybe_unused)
277{
278	if (str) {
279		params->command = opt->short_name;
280		return parse_probe_event(str);
281	}
282
283	return 0;
284}
285
286static int opt_set_filter_with_command(const struct option *opt,
287				       const char *str, int unset)
288{
289	if (!unset)
290		params->command = opt->short_name;
291
292	if (str)
293		return params_add_filter(str);
294
295	return 0;
296}
297
298static int opt_set_filter(const struct option *opt __maybe_unused,
299			  const char *str, int unset __maybe_unused)
300{
301	if (str)
302		return params_add_filter(str);
303
304	return 0;
305}
306
307static int init_params(void)
308{
309	int ret;
310
311	params = calloc(1, sizeof(*params));
312	if (!params)
313		return -ENOMEM;
314
315	ret = line_range__init(&params->line_range);
316	if (ret)
317		zfree(&params);
318	return ret;
319}
320
321static void cleanup_params(void)
322{
323	int i;
324
325	for (i = 0; i < params->nevents; i++)
326		clear_perf_probe_event(params->events + i);
327	line_range__clear(&params->line_range);
328	zfree(&params->target);
329	strfilter__delete(params->filter);
330	nsinfo__put(params->nsi);
331	zfree(&params);
332}
333
334static void pr_err_with_code(const char *msg, int err)
335{
336	char sbuf[STRERR_BUFSIZE];
337
338	pr_err("%s", msg);
339	pr_debug(" Reason: %s (Code: %d)",
340		 str_error_r(-err, sbuf, sizeof(sbuf)), err);
341	pr_err("\n");
342}
343
344static int perf_add_probe_events(struct perf_probe_event *pevs, int npevs)
345{
346	int ret;
347	int i, k;
348	const char *event = NULL, *group = NULL;
349
350	ret = init_probe_symbol_maps(pevs->uprobes);
351	if (ret < 0)
352		return ret;
353
354	ret = convert_perf_probe_events(pevs, npevs);
355	if (ret < 0)
356		goto out_cleanup;
357
358	if (params->command == 'D') {	/* it shows definition */
359		if (probe_conf.bootconfig)
360			ret = show_bootconfig_events(pevs, npevs);
361		else
362			ret = show_probe_trace_events(pevs, npevs);
363		goto out_cleanup;
364	}
365
366	ret = apply_perf_probe_events(pevs, npevs);
367	if (ret < 0)
368		goto out_cleanup;
369
370	for (i = k = 0; i < npevs; i++)
371		k += pevs[i].ntevs;
372
373	pr_info("Added new event%s\n", (k > 1) ? "s:" : ":");
374	for (i = 0; i < npevs; i++) {
375		struct perf_probe_event *pev = &pevs[i];
376
377		for (k = 0; k < pev->ntevs; k++) {
378			struct probe_trace_event *tev = &pev->tevs[k];
379			/* Skipped events have no event name */
380			if (!tev->event)
381				continue;
382
383			/* We use tev's name for showing new events */
384			show_perf_probe_event(tev->group, tev->event, pev,
385					      tev->point.module, false);
386
387			/* Save the last valid name */
388			event = tev->event;
389			group = tev->group;
390		}
391	}
392
393	/* Note that it is possible to skip all events because of blacklist */
394	if (event) {
395#ifndef HAVE_LIBTRACEEVENT
396		pr_info("\nperf is not linked with libtraceevent, to use the new probe you can use tracefs:\n\n");
397		pr_info("\tcd /sys/kernel/tracing/\n");
398		pr_info("\techo 1 > events/%s/%s/enable\n", group, event);
399		pr_info("\techo 1 > tracing_on\n");
400		pr_info("\tcat trace_pipe\n");
401		pr_info("\tBefore removing the probe, echo 0 > events/%s/%s/enable\n", group, event);
402#else
403		/* Show how to use the event. */
404		pr_info("\nYou can now use it in all perf tools, such as:\n\n");
405		pr_info("\tperf record -e %s:%s -aR sleep 1\n\n", group, event);
406#endif
407	}
408
409out_cleanup:
410	cleanup_perf_probe_events(pevs, npevs);
411	exit_probe_symbol_maps();
412	return ret;
413}
414
415static int del_perf_probe_caches(struct strfilter *filter)
416{
417	struct probe_cache *cache;
418	struct strlist *bidlist;
419	struct str_node *nd;
420	int ret;
421
422	bidlist = build_id_cache__list_all(false);
423	if (!bidlist) {
424		ret = -errno;
425		pr_debug("Failed to get buildids: %d\n", ret);
426		return ret ?: -ENOMEM;
427	}
428
429	strlist__for_each_entry(nd, bidlist) {
430		cache = probe_cache__new(nd->s, NULL);
431		if (!cache)
432			continue;
433		if (probe_cache__filter_purge(cache, filter) < 0 ||
434		    probe_cache__commit(cache) < 0)
435			pr_warning("Failed to remove entries for %s\n", nd->s);
436		probe_cache__delete(cache);
437	}
438	return 0;
439}
440
441static int perf_del_probe_events(struct strfilter *filter)
442{
443	int ret, ret2, ufd = -1, kfd = -1;
444	char *str = strfilter__string(filter);
445	struct strlist *klist = NULL, *ulist = NULL;
446	struct str_node *ent;
447
448	if (!str)
449		return -EINVAL;
450
451	pr_debug("Delete filter: \'%s\'\n", str);
452
453	if (probe_conf.cache)
454		return del_perf_probe_caches(filter);
455
456	/* Get current event names */
457	ret = probe_file__open_both(&kfd, &ufd, PF_FL_RW);
458	if (ret < 0)
459		goto out;
460
461	klist = strlist__new(NULL, NULL);
462	ulist = strlist__new(NULL, NULL);
463	if (!klist || !ulist) {
464		ret = -ENOMEM;
465		goto out;
466	}
467
468	ret = probe_file__get_events(kfd, filter, klist);
469	if (ret == 0) {
470		strlist__for_each_entry(ent, klist)
471			pr_info("Removed event: %s\n", ent->s);
472
473		ret = probe_file__del_strlist(kfd, klist);
474		if (ret < 0)
475			goto error;
476	} else if (ret == -ENOMEM)
477		goto error;
478
479	ret2 = probe_file__get_events(ufd, filter, ulist);
480	if (ret2 == 0) {
481		strlist__for_each_entry(ent, ulist)
482			pr_info("Removed event: %s\n", ent->s);
483
484		ret2 = probe_file__del_strlist(ufd, ulist);
485		if (ret2 < 0)
486			goto error;
487	} else if (ret2 == -ENOMEM)
488		goto error;
489
490	if (ret == -ENOENT && ret2 == -ENOENT)
491		pr_warning("\"%s\" does not hit any event.\n", str);
492	else
493		ret = 0;
494
495error:
496	if (kfd >= 0)
497		close(kfd);
498	if (ufd >= 0)
499		close(ufd);
500out:
501	strlist__delete(klist);
502	strlist__delete(ulist);
503	free(str);
504
505	return ret;
506}
507
508#ifdef HAVE_LIBDW_SUPPORT
509#define PROBEDEF_STR	\
510	"[EVENT=]FUNC[@SRC][+OFF|%return|:RL|;PT]|SRC:AL|SRC;PT [[NAME=]ARG ...]"
511#else
512#define PROBEDEF_STR	"[EVENT=]FUNC[+OFF|%return] [[NAME=]ARG ...]"
513#endif
514
515
516static int
517__cmd_probe(int argc, const char **argv)
518{
519	const char * const probe_usage[] = {
520		"perf probe [<options>] 'PROBEDEF' ['PROBEDEF' ...]",
521		"perf probe [<options>] --add 'PROBEDEF' [--add 'PROBEDEF' ...]",
522		"perf probe [<options>] --del '[GROUP:]EVENT' ...",
523		"perf probe --list [GROUP:]EVENT ...",
524#ifdef HAVE_LIBDW_SUPPORT
525		"perf probe [<options>] --line 'LINEDESC'",
526		"perf probe [<options>] --vars 'PROBEPOINT'",
527#endif
528		"perf probe [<options>] --funcs",
529		NULL
530	};
531	struct option options[] = {
532	OPT_INCR('v', "verbose", &verbose,
533		    "be more verbose (show parsed arguments, etc)"),
534	OPT_BOOLEAN('q', "quiet", &quiet,
535		    "be quiet (do not show any warnings or messages)"),
536	OPT_CALLBACK_DEFAULT('l', "list", NULL, "[GROUP:]EVENT",
537			     "list up probe events",
538			     opt_set_filter_with_command, DEFAULT_LIST_FILTER),
539	OPT_CALLBACK('d', "del", NULL, "[GROUP:]EVENT", "delete a probe event.",
540		     opt_set_filter_with_command),
541	OPT_CALLBACK('a', "add", NULL, PROBEDEF_STR,
542		"probe point definition, where\n"
543		"\t\tGROUP:\tGroup name (optional)\n"
544		"\t\tEVENT:\tEvent name\n"
545		"\t\tFUNC:\tFunction name\n"
546		"\t\tOFF:\tOffset from function entry (in byte)\n"
547		"\t\t%return:\tPut the probe at function return\n"
548#ifdef HAVE_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",
555#else
556		"\t\tARG:\tProbe argument (kprobe-tracer argument format.)\n",
557#endif
558		opt_add_probe_event),
559	OPT_CALLBACK('D', "definition", NULL, PROBEDEF_STR,
560		"Show trace event definition of given traceevent for k/uprobe_events.",
561		opt_add_probe_event),
562	OPT_BOOLEAN('f', "force", &probe_conf.force_add, "forcibly add events"
563		    " with existing name"),
564	OPT_CALLBACK('L', "line", NULL,
565		     "FUNC[:RLN[+NUM|-RLN2]]|SRC:ALN[+NUM|-ALN2]",
566		     "Show source code lines.", opt_show_lines),
567	OPT_CALLBACK('V', "vars", NULL,
568		     "FUNC[@SRC][+OFF|%return|:RL|;PT]|SRC:AL|SRC;PT",
569		     "Show accessible variables on PROBEDEF", opt_show_vars),
570	OPT_BOOLEAN('\0', "externs", &probe_conf.show_ext_vars,
571		    "Show external variables too (with --vars only)"),
572	OPT_BOOLEAN('\0', "range", &probe_conf.show_location_range,
573		"Show variables location range in scope (with --vars only)"),
574	OPT_STRING('k', "vmlinux", &symbol_conf.vmlinux_name,
575		   "file", "vmlinux pathname"),
576	OPT_STRING('s', "source", &symbol_conf.source_prefix,
577		   "directory", "path to kernel source"),
578	OPT_BOOLEAN('\0', "no-inlines", &probe_conf.no_inlines,
579		"Don't search inlined functions"),
580	OPT__DRY_RUN(&probe_event_dry_run),
581	OPT_INTEGER('\0', "max-probes", &probe_conf.max_probes,
582		 "Set how many probe points can be found for a probe."),
583	OPT_CALLBACK_DEFAULT('F', "funcs", NULL, "[FILTER]",
584			     "Show potential probe-able functions.",
585			     opt_set_filter_with_command, DEFAULT_FUNC_FILTER),
586	OPT_CALLBACK('\0', "filter", NULL,
587		     "[!]FILTER", "Set a filter (with --vars/funcs only)\n"
588		     "\t\t\t(default: \"" DEFAULT_VAR_FILTER "\" for --vars,\n"
589		     "\t\t\t \"" DEFAULT_FUNC_FILTER "\" for --funcs)",
590		     opt_set_filter),
591	OPT_CALLBACK('x', "exec", NULL, "executable|path",
592			"target executable name or path", opt_set_target),
593	OPT_CALLBACK('m', "module", NULL, "modname|path",
594		"target module name (for online) or path (for offline)",
595		opt_set_target),
596	OPT_BOOLEAN(0, "demangle", &symbol_conf.demangle,
597		    "Enable symbol demangling"),
598	OPT_BOOLEAN(0, "demangle-kernel", &symbol_conf.demangle_kernel,
599		    "Enable kernel symbol demangling"),
600	OPT_BOOLEAN(0, "cache", &probe_conf.cache, "Manipulate probe cache"),
601	OPT_STRING(0, "symfs", &symbol_conf.symfs, "directory",
602		   "Look for files with symbols relative to this directory"),
603	OPT_CALLBACK(0, "target-ns", NULL, "pid",
604		     "target pid for namespace contexts", opt_set_target_ns),
605	OPT_BOOLEAN(0, "bootconfig", &probe_conf.bootconfig,
606		    "Output probe definition with bootconfig format"),
607	OPT_END()
608	};
609	int ret;
610
611	set_option_flag(options, 'a', "add", PARSE_OPT_EXCLUSIVE);
612	set_option_flag(options, 'd', "del", PARSE_OPT_EXCLUSIVE);
613	set_option_flag(options, 'D', "definition", PARSE_OPT_EXCLUSIVE);
614	set_option_flag(options, 'l', "list", PARSE_OPT_EXCLUSIVE);
615#ifdef HAVE_LIBDW_SUPPORT
616	set_option_flag(options, 'L', "line", PARSE_OPT_EXCLUSIVE);
617	set_option_flag(options, 'V', "vars", PARSE_OPT_EXCLUSIVE);
618#else
619# define set_nobuild(s, l, c) set_option_nobuild(options, s, l, "NO_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);
627# undef set_nobuild
628#endif
629	set_option_flag(options, 'F', "funcs", PARSE_OPT_EXCLUSIVE);
630
631	argc = parse_options(argc, argv, options, probe_usage,
632			     PARSE_OPT_STOP_AT_NON_OPTION);
633
634	if (quiet) {
635		if (verbose != 0) {
636			pr_err("  Error: -v and -q are exclusive.\n");
637			return -EINVAL;
638		}
639		verbose = -1;
640	}
641
642	if (argc > 0) {
643		if (strcmp(argv[0], "-") == 0) {
644			usage_with_options_msg(probe_usage, options,
645				"'-' is not supported.\n");
646		}
647		if (params->command && params->command != 'a') {
648			usage_with_options_msg(probe_usage, options,
649				"another command except --add is set.\n");
650		}
651		ret = parse_probe_event_argv(argc, argv);
652		if (ret < 0) {
653			pr_err_with_code("  Error: Command Parse Error.", ret);
654			return ret;
655		}
656		params->command = 'a';
657	}
658
659	ret = symbol__validate_sym_arguments();
660	if (ret)
661		return ret;
662
663	if (probe_conf.max_probes == 0)
664		probe_conf.max_probes = MAX_PROBES;
665
666	/*
667	 * Only consider the user's kernel image path if given.
668	 */
669	symbol_conf.try_vmlinux_path = (symbol_conf.vmlinux_name == NULL);
670
671	/*
672	 * Except for --list, --del and --add, other command doesn't depend
673	 * nor change running kernel. So if user gives offline vmlinux,
674	 * ignore its buildid.
675	 */
676	if (!strchr("lda", params->command) && symbol_conf.vmlinux_name)
677		symbol_conf.ignore_vmlinux_buildid = true;
678
679	switch (params->command) {
680	case 'l':
681		if (params->uprobes) {
682			pr_err("  Error: Don't use --list with --exec.\n");
683			parse_options_usage(probe_usage, options, "l", true);
684			parse_options_usage(NULL, options, "x", true);
685			return -EINVAL;
686		}
687		ret = show_perf_probe_events(params->filter);
688		if (ret < 0)
689			pr_err_with_code("  Error: Failed to show event list.", ret);
690		return ret;
691	case 'F':
692		ret = show_available_funcs(params->target, params->nsi,
693					   params->filter, params->uprobes);
694		if (ret < 0)
695			pr_err_with_code("  Error: Failed to show functions.", ret);
696		return ret;
697#ifdef HAVE_LIBDW_SUPPORT
698	case 'L':
699		ret = show_line_range(&params->line_range, params->target,
700				      params->nsi, params->uprobes);
701		if (ret < 0)
702			pr_err_with_code("  Error: Failed to show lines.", ret);
703		return ret;
704	case 'V':
705		if (!params->filter)
706			params->filter = strfilter__new(DEFAULT_VAR_FILTER,
707						       NULL);
708
709		ret = show_available_vars(params->events, params->nevents,
710					  params->filter);
711		if (ret < 0)
712			pr_err_with_code("  Error: Failed to show vars.", ret);
713		return ret;
714#endif
715	case 'd':
716		ret = perf_del_probe_events(params->filter);
717		if (ret < 0) {
718			pr_err_with_code("  Error: Failed to delete events.", ret);
719			return ret;
720		}
721		break;
722	case 'D':
723		if (probe_conf.bootconfig && params->uprobes) {
724			pr_err("  Error: --bootconfig doesn't support uprobes.\n");
725			return -EINVAL;
726		}
727		fallthrough;
728	case 'a':
729
730		/* Ensure the last given target is used */
731		if (params->target && !params->target_used) {
732			pr_err("  Error: -x/-m must follow the probe definitions.\n");
733			parse_options_usage(probe_usage, options, "m", true);
734			parse_options_usage(NULL, options, "x", true);
735			return -EINVAL;
736		}
737
738		ret = perf_add_probe_events(params->events, params->nevents);
739		if (ret < 0) {
740
741			/*
742			 * When perf_add_probe_events() fails it calls
743			 * cleanup_perf_probe_events(pevs, npevs), i.e.
744			 * cleanup_perf_probe_events(params->events, params->nevents), which
745			 * will call clear_perf_probe_event(), so set nevents to zero
746			 * to avoid cleanup_params() to call clear_perf_probe_event() again
747			 * on the same pevs.
748			 */
749			params->nevents = 0;
750			pr_err_with_code("  Error: Failed to add events.", ret);
751			return ret;
752		}
753		break;
754	default:
755		usage_with_options(probe_usage, options);
756	}
757	return 0;
758}
759
760int cmd_probe(int argc, const char **argv)
761{
762	int ret;
763
764	ret = init_params();
765	if (!ret) {
766		ret = __cmd_probe(argc, argv);
767		cleanup_params();
768	}
769
770	return ret < 0 ? ret : 0;
771}