summaryrefslogtreecommitdiffstats
path: root/tools/perf/builtin-probe.c
blob: 1272559fa22d9eb60367f34594ebd18a7e76e8d3 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
/*
 * builtin-probe.c
 *
 * Builtin probe command: Set up probe events by C expression
 *
 * Written by Masami Hiramatsu <mhiramat@redhat.com>
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
 *
 */
#include <sys/utsname.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h>
#include <errno.h>
#include <stdio.h>
#include <unistd.h>
#include <stdlib.h>
#include <string.h>

#include "perf.h"
#include "builtin.h"
#include "util/util.h"
#include "util/strlist.h"
#include "util/strfilter.h"
#include "util/symbol.h"
#include "util/debug.h"
#include <api/fs/debugfs.h>
#include "util/parse-options.h"
#include "util/probe-finder.h"
#include "util/probe-event.h"

#define DEFAULT_VAR_FILTER "!__k???tab_* & !__crc_*"
#define DEFAULT_FUNC_FILTER "!_*"
#define DEFAULT_LIST_FILTER "*:*"

/* Session management structure */
static struct {
	int command;	/* Command short_name */
	bool list_events;
	bool uprobes;
	bool quiet;
	bool target_used;
	int nevents;
	struct perf_probe_event events[MAX_PROBES];
	struct line_range line_range;
	char *target;
	struct strfilter *filter;
} params;

/* Parse an event definition. Note that any error must die. */
static int parse_probe_event(const char *str)
{
	struct perf_probe_event *pev = &params.events[params.nevents];
	int ret;

	pr_debug("probe-definition(%d): %s\n", params.nevents, str);
	if (++params.nevents == MAX_PROBES) {
		pr_err("Too many probes (> %d) were specified.", MAX_PROBES);
		return -1;
	}

	pev->uprobes = params.uprobes;
	if (params.target) {
		pev->target = strdup(params.target);
		if (!pev->target)
			return -ENOMEM;
		params.target_used = true;
	}

	/* Parse a perf-probe command into event */
	ret = parse_perf_probe_command(str, pev);
	pr_debug("%d arguments\n", pev->nargs);

	return ret;
}

static int params_add_filter(const char *str)
{
	const char *err = NULL;
	int ret = 0;

	pr_debug2("Add filter: %s\n", str);
	if (!params.filter) {
		params.filter = strfilter__new(str, &err);
		if (!params.filter)
			ret = err ? -EINVAL : -ENOMEM;
	} else
		ret = strfilter__or(params.filter, str, &err);

	if (ret == -EINVAL) {
		pr_err("Filter parse error at %td.\n", err - str + 1);
		pr_err("Source: \"%s\"\n", str);
		pr_err("         %*c\n", (int)(err - str + 1), '^');
	}

	return ret;
}

static int set_target(const char *ptr)
{
	int found = 0;
	const char *buf;

	/*
	 * The first argument after options can be an absolute path
	 * to an executable / library or kernel module.
	 *
	 * TODO: Support relative path, and $PATH, $LD_LIBRARY_PATH,
	 * short module name.
	 */
	if (!params.target && ptr && *ptr == '/') {
		params.target = strdup(ptr);
		if (!params.target)
			return -ENOMEM;
		params.target_used = false;

		found = 1;
		buf = ptr + (strlen(ptr) - 3);

		if (strcmp(buf, ".ko"))
			params.uprobes = true;

	}

	return found;
}

static int parse_probe_event_argv(int argc, const char **argv)
{
	int i, len, ret, found_target;
	char *buf;

	found_target = set_target(argv[0]);
	if (found_target < 0)
		return found_target;

	if (found_target && argc == 1)
		return 0;

	/* Bind up rest arguments */
	len = 0;
	for (i = 0; i < argc; i++) {
		if (i == 0 && found_target)
			continue;

		len += strlen(argv[i]) + 1;
	}
	buf = zalloc(len + 1);
	if (buf == NULL)
		return -ENOMEM;
	len = 0;
	for (i = 0; i < argc; i++) {
		if (i == 0 && found_target)
			continue;

		len += sprintf(&buf[len], "%s ", argv[i]);
	}
	ret = parse_probe_event(buf);
	free(buf);
	return ret;
}

static int opt_set_target(const struct option *opt, const char *str,
			int unset __maybe_unused)
{
	int ret = -ENOENT;
	char *tmp;

	if  (str) {
		if (!strcmp(opt->long_name, "exec"))
			params.uprobes = true;
#ifdef HAVE_DWARF_SUPPORT
		else if (!strcmp(opt->long_name, "module"))
			params.uprobes = false;
#endif
		else
			return ret;

		/* Expand given path to absolute path, except for modulename */
		if (params.uprobes || strchr(str, '/')) {
			tmp = realpath(str, NULL);
			if (!tmp) {
				pr_warning("Failed to get the absolute path of %s: %m\n", str);
				return ret;
			}
		} else {
			tmp = strdup(str);
			if (!tmp)
				return -ENOMEM;
		}
		free(params.target);
		params.target = tmp;
		params.target_used = false;
		ret = 0;
	}

	return ret;
}

/* Command option callbacks */

#ifdef HAVE_DWARF_SUPPORT
static int opt_show_lines(const struct option *opt,
			  const char *str, int unset __maybe_unused)
{
	int ret = 0;

	if (!str)
		return 0;

	if (params.command == 'L') {
		pr_warning("Warning: more than one --line options are"
			   " detected. Only the first one is valid.\n");
		return 0;
	}

	params.command = opt->short_name;
	ret = parse_line_range_desc(str, &params.line_range);

	return ret;
}

static int opt_show_vars(const struct option *opt,
			 const char *str, int unset __maybe_unused)
{
	struct perf_probe_event *pev = &params.events[params.nevents];
	int ret;

	if (!str)
		return 0;

	ret = parse_probe_event(str);
	if (!ret && pev->nargs != 0) {
		pr_err("  Error: '--vars' doesn't accept arguments.\n");
		return -EINVAL;
	}
	params.command = opt->short_name;

	return ret;
}
#endif
static int opt_add_probe_event(const struct option *opt,
			      const char *str, int unset __maybe_unused)
{
	if (str) {
		params.command = opt->short_name;
		return parse_probe_event(str);
	}

	return 0;
}

static int opt_set_filter_with_command(const struct option *opt,
				       const char *str, int unset)
{
	if (!unset)
		params.command = opt->short_name;

	if (str)
		return params_add_filter(str);

	return 0;
}

static int opt_set_filter(const struct option *opt __maybe_unused,
			  const char *str, int unset __maybe_unused)
{
	if (str)
		return params_add_filter(str);

	return 0;
}

static int init_params(void)
{
	return line_range__init(&params.line_range);
}

static void cleanup_params(void)
{
	int i;

	for (i = 0; i < params.nevents; i++)
		clear_perf_probe_event(params.events + i);
	line_range__clear(&params.line_range);
	free(params.target);
	if (params.filter)
		strfilter__delete(params.filter);
	memset(&params, 0, sizeof(params));
}

static void pr_err_with_code(const char *msg, int err)
{
	char sbuf[STRERR_BUFSIZE];

	pr_err("%s", msg);
	pr_debug(" Reason: %s (Code: %d)",
		 strerror_r(-err, sbuf, sizeof(sbuf)), err);
	pr_err("\n");
}

static int
__cmd_probe(int argc, const char **argv, const char *prefix __maybe_unused)
{
	const char * const probe_usage[] = {
		"perf probe [<options>] 'PROBEDEF' ['PROBEDEF' ...]",
		"perf probe [<options>] --add 'PROBEDEF' [--add 'PROBEDEF' ...]",
		"perf probe [<options>] --del '[GROUP:]EVENT' ...",
		"perf probe --list [GROUP:]EVENT ...",
#ifdef HAVE_DWARF_SUPPORT
		"perf probe [<options>] --line 'LINEDESC'",
		"perf probe [<options>] --vars 'PROBEPOINT'",
#endif
		"perf probe [<options>] --funcs",
		NULL
	};
	struct option options[] = {
	OPT_INCR('v', "verbose", &verbose,
		    "be more verbose (show parsed arguments, etc)"),
	OPT_BOOLEAN('q', "quiet", &params.quiet,
		    "be quiet (do not show any mesages)"),
	OPT_CALLBACK_DEFAULT('l', "list", NULL, "[GROUP:]EVENT",
			     "list up probe events",
			     opt_set_filter_with_command, DEFAULT_LIST_FILTER),
	OPT_CALLBACK('d', "del", NULL, "[GROUP:]EVENT", "delete a probe event.",
		     opt_set_filter_with_command),
	OPT_CALLBACK('a', "add", NULL,
#ifdef HAVE_DWARF_SUPPORT
		"[EVENT=]FUNC[@SRC][+OFF|%return|:RL|;PT]|SRC:AL|SRC;PT"
		" [[NAME=]ARG ...]",
#else
		"[EVENT=]FUNC[+OFF|%return] [[NAME=]ARG ...]",
#endif
		"probe point definition, where\n"
		"\t\tGROUP:\tGroup name (optional)\n"
		"\t\tEVENT:\tEvent name\n"
		"\t\tFUNC:\tFunction name\n"
		"\t\tOFF:\tOffset from function entry (in byte)\n"
		"\t\t%return:\tPut the probe at function return\n"
#ifdef HAVE_DWARF_SUPPORT
		"\t\tSRC:\tSource code path\n"
		"\t\tRL:\tRelative line number from function entry.\n"
		"\t\tAL:\tAbsolute line number in file.\n"
		"\t\tPT:\tLazy expression of line code.\n"
		"\t\tARG:\tProbe argument (local variable name or\n"
		"\t\t\tkprobe-tracer argument format.)\n",
#else
		"\t\tARG:\tProbe argument (kprobe-tracer argument format.)\n",
#endif
		opt_add_probe_event),
	OPT_BOOLEAN('f', "force", &probe_conf.force_add, "forcibly add events"
		    " with existing name"),
#ifdef HAVE_DWARF_SUPPORT
	OPT_CALLBACK('L', "line", NULL,
		     "FUNC[:RLN[+NUM|-RLN2]]|SRC:ALN[+NUM|-ALN2]",
		     "Show source code lines.", opt_show_lines),
	OPT_CALLBACK('V', "vars", NULL,
		     "FUNC[@SRC][+OFF|%return|:RL|;PT]|SRC:AL|SRC;PT",
		     "Show accessible variables on PROBEDEF", opt_show_vars),
	OPT_BOOLEAN('\0', "externs", &probe_conf.show_ext_vars,
		    "Show external variables too (with --vars only)"),
	OPT_BOOLEAN('\0', "range", &probe_conf.show_location_range,
		"Show variables location range in scope (with --vars only)"),
	OPT_STRING('k', "vmlinux", &symbol_conf.vmlinux_name,
		   "file", "vmlinux pathname"),
	OPT_STRING('s', "source", &symbol_conf.source_prefix,
		   "directory", "path to kernel source"),
	OPT_CALLBACK('m', "module", NULL, "modname|path",
		"target module name (for online) or path (for offline)",
		opt_set_target),
	OPT_BOOLEAN('\0', "no-inlines", &probe_conf.no_inlines,
		"Don't search inlined functions"),
#endif
	OPT__DRY_RUN(&probe_event_dry_run),
	OPT_INTEGER('\0', "max-probes", &probe_conf.max_probes,
		 "Set how many probe points can be found for a probe."),
	OPT_CALLBACK_DEFAULT('F', "funcs", NULL, "[FILTER]",
			     "Show potential probe-able functions.",
			     opt_set_filter_with_command, DEFAULT_FUNC_FILTER),
	OPT_CALLBACK('\0', "filter", NULL,
		     "[!]FILTER", "Set a filter (with --vars/funcs only)\n"
		     "\t\t\t(default: \"" DEFAULT_VAR_FILTER "\" for --vars,\n"
		     "\t\t\t \"" DEFAULT_FUNC_FILTER "\" for --funcs)",
		     opt_set_filter),
	OPT_CALLBACK('x', "exec", NULL, "executable|path",
			"target executable name or path", opt_set_target),
	OPT_BOOLEAN(0, "demangle", &symbol_conf.demangle,
		    "Enable symbol demangling"),
	OPT_BOOLEAN(0, "demangle-kernel", &symbol_conf.demangle_kernel,
		    "Enable kernel symbol demangling"),
	OPT_END()
	};
	int ret;

	set_option_flag(options, 'a', "add", PARSE_OPT_EXCLUSIVE);
	set_option_flag(options, 'd', "del", PARSE_OPT_EXCLUSIVE);
	set_option_flag(options, 'l', "list", PARSE_OPT_EXCLUSIVE);
#ifdef HAVE_DWARF_SUPPORT
	set_option_flag(options, 'L', "line", PARSE_OPT_EXCLUSIVE);
	set_option_flag(options, 'V', "vars", PARSE_OPT_EXCLUSIVE);
#endif
	set_option_flag(options, 'F', "funcs", PARSE_OPT_EXCLUSIVE);

	argc = parse_options(argc, argv, options, probe_usage,
			     PARSE_OPT_STOP_AT_NON_OPTION);
	if (argc > 0) {
		if (strcmp(argv[0], "-") == 0) {
			pr_warning("  Error: '-' is not supported.\n");
			usage_with_options(probe_usage, options);
		}
		if (params.command && params.command != 'a') {
			pr_warning("  Error: another command except --add is set.\n");
			usage_with_options(probe_usage, options);
		}
		ret = parse_probe_event_argv(argc, argv);
		if (ret < 0) {
			pr_err_with_code("  Error: Command Parse Error.", ret);
			return ret;
		}
		params.command = 'a';
	}

	if (params.quiet) {
		if (verbose != 0) {
			pr_err("  Error: -v and -q are exclusive.\n");
			return -EINVAL;
		}
		verbose = -1;
	}

	if (probe_conf.max_probes == 0)
		probe_conf.max_probes = MAX_PROBES;

	/*
	 * Only consider the user's kernel image path if given.
	 */
	symbol_conf.try_vmlinux_path = (symbol_conf.vmlinux_name == NULL);

	switch (params.command) {
	case 'l':
		if (params.uprobes) {
			pr_warning("  Error: Don't use --list with --exec.\n");
			usage_with_options(probe_usage, options);
		}
		ret = show_perf_probe_events(params.filter);
		if (ret < 0)
			pr_err_with_code("  Error: Failed to show event list.", ret);
		return ret;
	case 'F':
		ret = show_available_funcs(params.target, params.filter,
					params.uprobes);
		if (ret < 0)
			pr_err_with_code("  Error: Failed to show functions.", ret);
		return ret;
#ifdef HAVE_DWARF_SUPPORT
	case 'L':
		ret = show_line_range(&params.line_range, params.target,
				      params.uprobes);
		if (ret < 0)
			pr_err_with_code("  Error: Failed to show lines.", ret);
		return ret;
	case 'V':
		if (!params.filter)
			params.filter = strfilter__new(DEFAULT_VAR_FILTER,
						       NULL);

		ret = show_available_vars(params.events, params.nevents,
					  params.filter);
		if (ret < 0)
			pr_err_with_code("  Error: Failed to show vars.", ret);
		return ret;
#endif
	case 'd':
		ret = del_perf_probe_events(params.filter);
		if (ret < 0) {
			pr_err_with_code("  Error: Failed to delete events.", ret);
			return ret;
		}
		break;
	case 'a':
		/* Ensure the last given target is used */
		if (params.target && !params.target_used) {
			pr_warning("  Error: -x/-m must follow the probe definitions.\n");
			usage_with_options(probe_usage, options);
		}

		ret = add_perf_probe_events(params.events, params.nevents);
		if (ret < 0) {
			pr_err_with_code("  Error: Failed to add events.", ret);
			return ret;
		}
		break;
	default:
		usage_with_options(probe_usage, options);
	}
	return 0;
}

int cmd_probe(int argc, const char **argv, const char *prefix)
{
	int ret;

	ret = init_params();
	if (!ret) {
		ret = __cmd_probe(argc, argv, prefix);
		cleanup_params();
	}

	return ret < 0 ? ret : 0;
}