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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 */
50 static 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. */
parse_probe_event(const char * str)64 static int parse_probe_event(const char *str)
65 {
66 	struct perf_probe_event *pev = &params.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 
params_add_filter(const char * str)90 static 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 
set_target(const char * ptr)112 static 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 
parse_probe_event_argv(int argc,const char ** argv)141 static 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 
opt_set_target(const struct option * opt,const char * str,int unset __maybe_unused)176 static 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
opt_show_lines(const struct option * opt,const char * str,int unset __maybe_unused)214 static 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, &params.line_range);
230 
231 	return ret;
232 }
233 
opt_show_vars(const struct option * opt,const char * str,int unset __maybe_unused)234 static int opt_show_vars(const struct option *opt,
235 			 const char *str, int unset __maybe_unused)
236 {
237 	struct perf_probe_event *pev = &params.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
opt_add_probe_event(const struct option * opt,const char * str,int unset __maybe_unused)256 static 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 
opt_set_filter_with_command(const struct option * opt,const char * str,int unset)267 static 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 
opt_set_filter(const struct option * opt __maybe_unused,const char * str,int unset __maybe_unused)279 static 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 
init_params(void)288 static int init_params(void)
289 {
290 	return line_range__init(&params.line_range);
291 }
292 
cleanup_params(void)293 static 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(&params.line_range);
300 	free(params.target);
301 	strfilter__delete(params.filter);
302 	memset(&params, 0, sizeof(params));
303 }
304 
pr_err_with_code(const char * msg,int err)305 static 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 
perf_add_probe_events(struct perf_probe_event * pevs,int npevs)315 static 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 
365 out_cleanup:
366 	cleanup_perf_probe_events(pevs, npevs);
367 	exit_probe_symbol_maps();
368 	return ret;
369 }
370 
del_perf_probe_caches(struct strfilter * filter)371 static 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 
perf_del_probe_events(struct strfilter * filter)397 static 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_warning("\"%s\" does not hit any event.\n", str);
446 	else
447 		ret = 0;
448 
449 error:
450 	if (kfd >= 0)
451 		close(kfd);
452 	if (ufd >= 0)
453 		close(ufd);
454 out:
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 
470 static int
__cmd_probe(int argc,const char ** argv,const char * prefix __maybe_unused)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", &params.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(&params.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 
cmd_probe(int argc,const char ** argv,const char * prefix)688 int 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 }
700