xref: /linux/tools/perf/perf.c (revision 110e6f26af80dfd90b6e5c645b1aed7228aa580d) 
1 /*
2  * perf.c
3  *
4  * Performance analysis utility.
5  *
6  * This is the main hub from which the sub-commands (perf stat,
7  * perf top, perf record, perf report, etc.) are started.
8  */
9 #include "builtin.h"
10 
11 #include "util/env.h"
12 #include <subcmd/exec-cmd.h>
13 #include "util/cache.h"
14 #include "util/quote.h"
15 #include <subcmd/run-command.h>
16 #include "util/parse-events.h"
17 #include <subcmd/parse-options.h>
18 #include "util/bpf-loader.h"
19 #include "util/debug.h"
20 #include <api/fs/tracing_path.h>
21 #include <pthread.h>
22 #include <stdlib.h>
23 #include <time.h>
24 
25 const char perf_usage_string[] =
26 	"perf [--version] [--help] [OPTIONS] COMMAND [ARGS]";
27 
28 const char perf_more_info_string[] =
29 	"See 'perf help COMMAND' for more information on a specific command.";
30 
31 int use_browser = -1;
32 static int use_pager = -1;
33 const char *input_name;
34 
35 struct cmd_struct {
36 	const char *cmd;
37 	int (*fn)(int, const char **, const char *);
38 	int option;
39 };
40 
41 static struct cmd_struct commands[] = {
42 	{ "buildid-cache", cmd_buildid_cache, 0 },
43 	{ "buildid-list", cmd_buildid_list, 0 },
44 	{ "config",	cmd_config,	0 },
45 	{ "diff",	cmd_diff,	0 },
46 	{ "evlist",	cmd_evlist,	0 },
47 	{ "help",	cmd_help,	0 },
48 	{ "list",	cmd_list,	0 },
49 	{ "record",	cmd_record,	0 },
50 	{ "report",	cmd_report,	0 },
51 	{ "bench",	cmd_bench,	0 },
52 	{ "stat",	cmd_stat,	0 },
53 	{ "timechart",	cmd_timechart,	0 },
54 	{ "top",	cmd_top,	0 },
55 	{ "annotate",	cmd_annotate,	0 },
56 	{ "version",	cmd_version,	0 },
57 	{ "script",	cmd_script,	0 },
58 	{ "sched",	cmd_sched,	0 },
59 #ifdef HAVE_LIBELF_SUPPORT
60 	{ "probe",	cmd_probe,	0 },
61 #endif
62 	{ "kmem",	cmd_kmem,	0 },
63 	{ "lock",	cmd_lock,	0 },
64 	{ "kvm",	cmd_kvm,	0 },
65 	{ "test",	cmd_test,	0 },
66 #ifdef HAVE_LIBAUDIT_SUPPORT
67 	{ "trace",	cmd_trace,	0 },
68 #endif
69 	{ "inject",	cmd_inject,	0 },
70 	{ "mem",	cmd_mem,	0 },
71 	{ "data",	cmd_data,	0 },
72 };
73 
74 struct pager_config {
75 	const char *cmd;
76 	int val;
77 };
78 
79 static int pager_command_config(const char *var, const char *value, void *data)
80 {
81 	struct pager_config *c = data;
82 	if (!prefixcmp(var, "pager.") && !strcmp(var + 6, c->cmd))
83 		c->val = perf_config_bool(var, value);
84 	return 0;
85 }
86 
87 /* returns 0 for "no pager", 1 for "use pager", and -1 for "not specified" */
88 int check_pager_config(const char *cmd)
89 {
90 	struct pager_config c;
91 	c.cmd = cmd;
92 	c.val = -1;
93 	perf_config(pager_command_config, &c);
94 	return c.val;
95 }
96 
97 static int browser_command_config(const char *var, const char *value, void *data)
98 {
99 	struct pager_config *c = data;
100 	if (!prefixcmp(var, "tui.") && !strcmp(var + 4, c->cmd))
101 		c->val = perf_config_bool(var, value);
102 	if (!prefixcmp(var, "gtk.") && !strcmp(var + 4, c->cmd))
103 		c->val = perf_config_bool(var, value) ? 2 : 0;
104 	return 0;
105 }
106 
107 /*
108  * returns 0 for "no tui", 1 for "use tui", 2 for "use gtk",
109  * and -1 for "not specified"
110  */
111 static int check_browser_config(const char *cmd)
112 {
113 	struct pager_config c;
114 	c.cmd = cmd;
115 	c.val = -1;
116 	perf_config(browser_command_config, &c);
117 	return c.val;
118 }
119 
120 static void commit_pager_choice(void)
121 {
122 	switch (use_pager) {
123 	case 0:
124 		setenv(PERF_PAGER_ENVIRONMENT, "cat", 1);
125 		break;
126 	case 1:
127 		/* setup_pager(); */
128 		break;
129 	default:
130 		break;
131 	}
132 }
133 
134 struct option options[] = {
135 	OPT_ARGUMENT("help", "help"),
136 	OPT_ARGUMENT("version", "version"),
137 	OPT_ARGUMENT("exec-path", "exec-path"),
138 	OPT_ARGUMENT("html-path", "html-path"),
139 	OPT_ARGUMENT("paginate", "paginate"),
140 	OPT_ARGUMENT("no-pager", "no-pager"),
141 	OPT_ARGUMENT("perf-dir", "perf-dir"),
142 	OPT_ARGUMENT("work-tree", "work-tree"),
143 	OPT_ARGUMENT("debugfs-dir", "debugfs-dir"),
144 	OPT_ARGUMENT("buildid-dir", "buildid-dir"),
145 	OPT_ARGUMENT("list-cmds", "list-cmds"),
146 	OPT_ARGUMENT("list-opts", "list-opts"),
147 	OPT_ARGUMENT("debug", "debug"),
148 	OPT_END()
149 };
150 
151 static int handle_options(const char ***argv, int *argc, int *envchanged)
152 {
153 	int handled = 0;
154 
155 	while (*argc > 0) {
156 		const char *cmd = (*argv)[0];
157 		if (cmd[0] != '-')
158 			break;
159 
160 		/*
161 		 * For legacy reasons, the "version" and "help"
162 		 * commands can be written with "--" prepended
163 		 * to make them look like flags.
164 		 */
165 		if (!strcmp(cmd, "--help") || !strcmp(cmd, "--version"))
166 			break;
167 
168 		/*
169 		 * Shortcut for '-h' and '-v' options to invoke help
170 		 * and version command.
171 		 */
172 		if (!strcmp(cmd, "-h")) {
173 			(*argv)[0] = "--help";
174 			break;
175 		}
176 
177 		if (!strcmp(cmd, "-v")) {
178 			(*argv)[0] = "--version";
179 			break;
180 		}
181 
182 		/*
183 		 * Check remaining flags.
184 		 */
185 		if (!prefixcmp(cmd, CMD_EXEC_PATH)) {
186 			cmd += strlen(CMD_EXEC_PATH);
187 			if (*cmd == '=')
188 				set_argv_exec_path(cmd + 1);
189 			else {
190 				puts(get_argv_exec_path());
191 				exit(0);
192 			}
193 		} else if (!strcmp(cmd, "--html-path")) {
194 			puts(system_path(PERF_HTML_PATH));
195 			exit(0);
196 		} else if (!strcmp(cmd, "-p") || !strcmp(cmd, "--paginate")) {
197 			use_pager = 1;
198 		} else if (!strcmp(cmd, "--no-pager")) {
199 			use_pager = 0;
200 			if (envchanged)
201 				*envchanged = 1;
202 		} else if (!strcmp(cmd, "--perf-dir")) {
203 			if (*argc < 2) {
204 				fprintf(stderr, "No directory given for --perf-dir.\n");
205 				usage(perf_usage_string);
206 			}
207 			setenv(PERF_DIR_ENVIRONMENT, (*argv)[1], 1);
208 			if (envchanged)
209 				*envchanged = 1;
210 			(*argv)++;
211 			(*argc)--;
212 			handled++;
213 		} else if (!prefixcmp(cmd, CMD_PERF_DIR)) {
214 			setenv(PERF_DIR_ENVIRONMENT, cmd + strlen(CMD_PERF_DIR), 1);
215 			if (envchanged)
216 				*envchanged = 1;
217 		} else if (!strcmp(cmd, "--work-tree")) {
218 			if (*argc < 2) {
219 				fprintf(stderr, "No directory given for --work-tree.\n");
220 				usage(perf_usage_string);
221 			}
222 			setenv(PERF_WORK_TREE_ENVIRONMENT, (*argv)[1], 1);
223 			if (envchanged)
224 				*envchanged = 1;
225 			(*argv)++;
226 			(*argc)--;
227 		} else if (!prefixcmp(cmd, CMD_WORK_TREE)) {
228 			setenv(PERF_WORK_TREE_ENVIRONMENT, cmd + strlen(CMD_WORK_TREE), 1);
229 			if (envchanged)
230 				*envchanged = 1;
231 		} else if (!strcmp(cmd, "--debugfs-dir")) {
232 			if (*argc < 2) {
233 				fprintf(stderr, "No directory given for --debugfs-dir.\n");
234 				usage(perf_usage_string);
235 			}
236 			tracing_path_set((*argv)[1]);
237 			if (envchanged)
238 				*envchanged = 1;
239 			(*argv)++;
240 			(*argc)--;
241 		} else if (!strcmp(cmd, "--buildid-dir")) {
242 			if (*argc < 2) {
243 				fprintf(stderr, "No directory given for --buildid-dir.\n");
244 				usage(perf_usage_string);
245 			}
246 			set_buildid_dir((*argv)[1]);
247 			if (envchanged)
248 				*envchanged = 1;
249 			(*argv)++;
250 			(*argc)--;
251 		} else if (!prefixcmp(cmd, CMD_DEBUGFS_DIR)) {
252 			tracing_path_set(cmd + strlen(CMD_DEBUGFS_DIR));
253 			fprintf(stderr, "dir: %s\n", tracing_path);
254 			if (envchanged)
255 				*envchanged = 1;
256 		} else if (!strcmp(cmd, "--list-cmds")) {
257 			unsigned int i;
258 
259 			for (i = 0; i < ARRAY_SIZE(commands); i++) {
260 				struct cmd_struct *p = commands+i;
261 				printf("%s ", p->cmd);
262 			}
263 			putchar('\n');
264 			exit(0);
265 		} else if (!strcmp(cmd, "--list-opts")) {
266 			unsigned int i;
267 
268 			for (i = 0; i < ARRAY_SIZE(options)-1; i++) {
269 				struct option *p = options+i;
270 				printf("--%s ", p->long_name);
271 			}
272 			putchar('\n');
273 			exit(0);
274 		} else if (!strcmp(cmd, "--debug")) {
275 			if (*argc < 2) {
276 				fprintf(stderr, "No variable specified for --debug.\n");
277 				usage(perf_usage_string);
278 			}
279 			if (perf_debug_option((*argv)[1]))
280 				usage(perf_usage_string);
281 
282 			(*argv)++;
283 			(*argc)--;
284 		} else {
285 			fprintf(stderr, "Unknown option: %s\n", cmd);
286 			usage(perf_usage_string);
287 		}
288 
289 		(*argv)++;
290 		(*argc)--;
291 		handled++;
292 	}
293 	return handled;
294 }
295 
296 static int handle_alias(int *argcp, const char ***argv)
297 {
298 	int envchanged = 0, ret = 0, saved_errno = errno;
299 	int count, option_count;
300 	const char **new_argv;
301 	const char *alias_command;
302 	char *alias_string;
303 
304 	alias_command = (*argv)[0];
305 	alias_string = alias_lookup(alias_command);
306 	if (alias_string) {
307 		if (alias_string[0] == '!') {
308 			if (*argcp > 1) {
309 				struct strbuf buf;
310 
311 				strbuf_init(&buf, PATH_MAX);
312 				strbuf_addstr(&buf, alias_string);
313 				sq_quote_argv(&buf, (*argv) + 1, PATH_MAX);
314 				free(alias_string);
315 				alias_string = buf.buf;
316 			}
317 			ret = system(alias_string + 1);
318 			if (ret >= 0 && WIFEXITED(ret) &&
319 			    WEXITSTATUS(ret) != 127)
320 				exit(WEXITSTATUS(ret));
321 			die("Failed to run '%s' when expanding alias '%s'",
322 			    alias_string + 1, alias_command);
323 		}
324 		count = split_cmdline(alias_string, &new_argv);
325 		if (count < 0)
326 			die("Bad alias.%s string", alias_command);
327 		option_count = handle_options(&new_argv, &count, &envchanged);
328 		if (envchanged)
329 			die("alias '%s' changes environment variables\n"
330 				 "You can use '!perf' in the alias to do this.",
331 				 alias_command);
332 		memmove(new_argv - option_count, new_argv,
333 				count * sizeof(char *));
334 		new_argv -= option_count;
335 
336 		if (count < 1)
337 			die("empty alias for %s", alias_command);
338 
339 		if (!strcmp(alias_command, new_argv[0]))
340 			die("recursive alias: %s", alias_command);
341 
342 		new_argv = realloc(new_argv, sizeof(char *) *
343 				    (count + *argcp + 1));
344 		/* insert after command name */
345 		memcpy(new_argv + count, *argv + 1, sizeof(char *) * *argcp);
346 		new_argv[count + *argcp] = NULL;
347 
348 		*argv = new_argv;
349 		*argcp += count - 1;
350 
351 		ret = 1;
352 	}
353 
354 	errno = saved_errno;
355 
356 	return ret;
357 }
358 
359 const char perf_version_string[] = PERF_VERSION;
360 
361 #define RUN_SETUP	(1<<0)
362 #define USE_PAGER	(1<<1)
363 /*
364  * require working tree to be present -- anything uses this needs
365  * RUN_SETUP for reading from the configuration file.
366  */
367 #define NEED_WORK_TREE	(1<<2)
368 
369 static int run_builtin(struct cmd_struct *p, int argc, const char **argv)
370 {
371 	int status;
372 	struct stat st;
373 	const char *prefix;
374 	char sbuf[STRERR_BUFSIZE];
375 
376 	prefix = NULL;
377 	if (p->option & RUN_SETUP)
378 		prefix = NULL; /* setup_perf_directory(); */
379 
380 	if (use_browser == -1)
381 		use_browser = check_browser_config(p->cmd);
382 
383 	if (use_pager == -1 && p->option & RUN_SETUP)
384 		use_pager = check_pager_config(p->cmd);
385 	if (use_pager == -1 && p->option & USE_PAGER)
386 		use_pager = 1;
387 	commit_pager_choice();
388 
389 	perf_env__set_cmdline(&perf_env, argc, argv);
390 	status = p->fn(argc, argv, prefix);
391 	exit_browser(status);
392 	perf_env__exit(&perf_env);
393 	bpf__clear();
394 
395 	if (status)
396 		return status & 0xff;
397 
398 	/* Somebody closed stdout? */
399 	if (fstat(fileno(stdout), &st))
400 		return 0;
401 	/* Ignore write errors for pipes and sockets.. */
402 	if (S_ISFIFO(st.st_mode) || S_ISSOCK(st.st_mode))
403 		return 0;
404 
405 	status = 1;
406 	/* Check for ENOSPC and EIO errors.. */
407 	if (fflush(stdout)) {
408 		fprintf(stderr, "write failure on standard output: %s",
409 			strerror_r(errno, sbuf, sizeof(sbuf)));
410 		goto out;
411 	}
412 	if (ferror(stdout)) {
413 		fprintf(stderr, "unknown write failure on standard output");
414 		goto out;
415 	}
416 	if (fclose(stdout)) {
417 		fprintf(stderr, "close failed on standard output: %s",
418 			strerror_r(errno, sbuf, sizeof(sbuf)));
419 		goto out;
420 	}
421 	status = 0;
422 out:
423 	return status;
424 }
425 
426 static void handle_internal_command(int argc, const char **argv)
427 {
428 	const char *cmd = argv[0];
429 	unsigned int i;
430 	static const char ext[] = STRIP_EXTENSION;
431 
432 	if (sizeof(ext) > 1) {
433 		i = strlen(argv[0]) - strlen(ext);
434 		if (i > 0 && !strcmp(argv[0] + i, ext)) {
435 			char *argv0 = strdup(argv[0]);
436 			argv[0] = cmd = argv0;
437 			argv0[i] = '\0';
438 		}
439 	}
440 
441 	/* Turn "perf cmd --help" into "perf help cmd" */
442 	if (argc > 1 && !strcmp(argv[1], "--help")) {
443 		argv[1] = argv[0];
444 		argv[0] = cmd = "help";
445 	}
446 
447 	for (i = 0; i < ARRAY_SIZE(commands); i++) {
448 		struct cmd_struct *p = commands+i;
449 		if (strcmp(p->cmd, cmd))
450 			continue;
451 		exit(run_builtin(p, argc, argv));
452 	}
453 }
454 
455 static void execv_dashed_external(const char **argv)
456 {
457 	char *cmd;
458 	const char *tmp;
459 	int status;
460 
461 	if (asprintf(&cmd, "perf-%s", argv[0]) < 0)
462 		goto do_die;
463 
464 	/*
465 	 * argv[0] must be the perf command, but the argv array
466 	 * belongs to the caller, and may be reused in
467 	 * subsequent loop iterations. Save argv[0] and
468 	 * restore it on error.
469 	 */
470 	tmp = argv[0];
471 	argv[0] = cmd;
472 
473 	/*
474 	 * if we fail because the command is not found, it is
475 	 * OK to return. Otherwise, we just pass along the status code.
476 	 */
477 	status = run_command_v_opt(argv, 0);
478 	if (status != -ERR_RUN_COMMAND_EXEC) {
479 		if (IS_RUN_COMMAND_ERR(status)) {
480 do_die:
481 			die("unable to run '%s'", argv[0]);
482 		}
483 		exit(-status);
484 	}
485 	errno = ENOENT; /* as if we called execvp */
486 
487 	argv[0] = tmp;
488 	zfree(&cmd);
489 }
490 
491 static int run_argv(int *argcp, const char ***argv)
492 {
493 	int done_alias = 0;
494 
495 	while (1) {
496 		/* See if it's an internal command */
497 		handle_internal_command(*argcp, *argv);
498 
499 		/* .. then try the external ones */
500 		execv_dashed_external(*argv);
501 
502 		/* It could be an alias -- this works around the insanity
503 		 * of overriding "perf log" with "perf show" by having
504 		 * alias.log = show
505 		 */
506 		if (done_alias || !handle_alias(argcp, argv))
507 			break;
508 		done_alias = 1;
509 	}
510 
511 	return done_alias;
512 }
513 
514 static void pthread__block_sigwinch(void)
515 {
516 	sigset_t set;
517 
518 	sigemptyset(&set);
519 	sigaddset(&set, SIGWINCH);
520 	pthread_sigmask(SIG_BLOCK, &set, NULL);
521 }
522 
523 void pthread__unblock_sigwinch(void)
524 {
525 	sigset_t set;
526 
527 	sigemptyset(&set);
528 	sigaddset(&set, SIGWINCH);
529 	pthread_sigmask(SIG_UNBLOCK, &set, NULL);
530 }
531 
532 int main(int argc, const char **argv)
533 {
534 	const char *cmd;
535 	char sbuf[STRERR_BUFSIZE];
536 
537 	/* libsubcmd init */
538 	exec_cmd_init("perf", PREFIX, PERF_EXEC_PATH, EXEC_PATH_ENVIRONMENT);
539 	pager_init(PERF_PAGER_ENVIRONMENT);
540 
541 	/* The page_size is placed in util object. */
542 	page_size = sysconf(_SC_PAGE_SIZE);
543 	cacheline_size = sysconf(_SC_LEVEL1_DCACHE_LINESIZE);
544 
545 	cmd = extract_argv0_path(argv[0]);
546 	if (!cmd)
547 		cmd = "perf-help";
548 
549 	srandom(time(NULL));
550 
551 	perf_config(perf_default_config, NULL);
552 
553 	/* get debugfs/tracefs mount point from /proc/mounts */
554 	tracing_path_mount();
555 
556 	/*
557 	 * "perf-xxxx" is the same as "perf xxxx", but we obviously:
558 	 *
559 	 *  - cannot take flags in between the "perf" and the "xxxx".
560 	 *  - cannot execute it externally (since it would just do
561 	 *    the same thing over again)
562 	 *
563 	 * So we just directly call the internal command handler, and
564 	 * die if that one cannot handle it.
565 	 */
566 	if (!prefixcmp(cmd, "perf-")) {
567 		cmd += 5;
568 		argv[0] = cmd;
569 		handle_internal_command(argc, argv);
570 		fprintf(stderr, "cannot handle %s internally", cmd);
571 		goto out;
572 	}
573 	if (!prefixcmp(cmd, "trace")) {
574 #ifdef HAVE_LIBAUDIT_SUPPORT
575 		set_buildid_dir(NULL);
576 		setup_path();
577 		argv[0] = "trace";
578 		return cmd_trace(argc, argv, NULL);
579 #else
580 		fprintf(stderr,
581 			"trace command not available: missing audit-libs devel package at build time.\n");
582 		goto out;
583 #endif
584 	}
585 	/* Look for flags.. */
586 	argv++;
587 	argc--;
588 	handle_options(&argv, &argc, NULL);
589 	commit_pager_choice();
590 	set_buildid_dir(NULL);
591 
592 	if (argc > 0) {
593 		if (!prefixcmp(argv[0], "--"))
594 			argv[0] += 2;
595 	} else {
596 		/* The user didn't specify a command; give them help */
597 		printf("\n usage: %s\n\n", perf_usage_string);
598 		list_common_cmds_help();
599 		printf("\n %s\n\n", perf_more_info_string);
600 		goto out;
601 	}
602 	cmd = argv[0];
603 
604 	test_attr__init();
605 
606 	/*
607 	 * We use PATH to find perf commands, but we prepend some higher
608 	 * precedence paths: the "--exec-path" option, the PERF_EXEC_PATH
609 	 * environment, and the $(perfexecdir) from the Makefile at build
610 	 * time.
611 	 */
612 	setup_path();
613 	/*
614 	 * Block SIGWINCH notifications so that the thread that wants it can
615 	 * unblock and get syscalls like select interrupted instead of waiting
616 	 * forever while the signal goes to some other non interested thread.
617 	 */
618 	pthread__block_sigwinch();
619 
620 	perf_debug_setup();
621 
622 	while (1) {
623 		static int done_help;
624 		int was_alias = run_argv(&argc, &argv);
625 
626 		if (errno != ENOENT)
627 			break;
628 
629 		if (was_alias) {
630 			fprintf(stderr, "Expansion of alias '%s' failed; "
631 				"'%s' is not a perf-command\n",
632 				cmd, argv[0]);
633 			goto out;
634 		}
635 		if (!done_help) {
636 			cmd = argv[0] = help_unknown_cmd(cmd);
637 			done_help = 1;
638 		} else
639 			break;
640 	}
641 
642 	fprintf(stderr, "Failed to run command '%s': %s\n",
643 		cmd, strerror_r(errno, sbuf, sizeof(sbuf)));
644 out:
645 	return 1;
646 }
647