xref: /linux/tools/perf/perf.c (revision 64af4e0da419ef9e9db0d34a3b5836adbf90a5e8) 
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 
23 const char perf_usage_string[] =
24 	"perf [--version] [--help] [OPTIONS] COMMAND [ARGS]";
25 
26 const char perf_more_info_string[] =
27 	"See 'perf help COMMAND' for more information on a specific command.";
28 
29 int use_browser = -1;
30 static int use_pager = -1;
31 const char *input_name;
32 
33 struct cmd_struct {
34 	const char *cmd;
35 	int (*fn)(int, const char **, const char *);
36 	int option;
37 };
38 
39 static struct cmd_struct commands[] = {
40 	{ "buildid-cache", cmd_buildid_cache, 0 },
41 	{ "buildid-list", cmd_buildid_list, 0 },
42 	{ "config",	cmd_config,	0 },
43 	{ "diff",	cmd_diff,	0 },
44 	{ "evlist",	cmd_evlist,	0 },
45 	{ "help",	cmd_help,	0 },
46 	{ "list",	cmd_list,	0 },
47 	{ "record",	cmd_record,	0 },
48 	{ "report",	cmd_report,	0 },
49 	{ "bench",	cmd_bench,	0 },
50 	{ "stat",	cmd_stat,	0 },
51 	{ "timechart",	cmd_timechart,	0 },
52 	{ "top",	cmd_top,	0 },
53 	{ "annotate",	cmd_annotate,	0 },
54 	{ "version",	cmd_version,	0 },
55 	{ "script",	cmd_script,	0 },
56 	{ "sched",	cmd_sched,	0 },
57 #ifdef HAVE_LIBELF_SUPPORT
58 	{ "probe",	cmd_probe,	0 },
59 #endif
60 	{ "kmem",	cmd_kmem,	0 },
61 	{ "lock",	cmd_lock,	0 },
62 	{ "kvm",	cmd_kvm,	0 },
63 	{ "test",	cmd_test,	0 },
64 #ifdef HAVE_LIBAUDIT_SUPPORT
65 	{ "trace",	cmd_trace,	0 },
66 #endif
67 	{ "inject",	cmd_inject,	0 },
68 	{ "mem",	cmd_mem,	0 },
69 	{ "data",	cmd_data,	0 },
70 };
71 
72 struct pager_config {
73 	const char *cmd;
74 	int val;
75 };
76 
77 static int pager_command_config(const char *var, const char *value, void *data)
78 {
79 	struct pager_config *c = data;
80 	if (!prefixcmp(var, "pager.") && !strcmp(var + 6, c->cmd))
81 		c->val = perf_config_bool(var, value);
82 	return 0;
83 }
84 
85 /* returns 0 for "no pager", 1 for "use pager", and -1 for "not specified" */
86 int check_pager_config(const char *cmd)
87 {
88 	struct pager_config c;
89 	c.cmd = cmd;
90 	c.val = -1;
91 	perf_config(pager_command_config, &c);
92 	return c.val;
93 }
94 
95 static int browser_command_config(const char *var, const char *value, void *data)
96 {
97 	struct pager_config *c = data;
98 	if (!prefixcmp(var, "tui.") && !strcmp(var + 4, c->cmd))
99 		c->val = perf_config_bool(var, value);
100 	if (!prefixcmp(var, "gtk.") && !strcmp(var + 4, c->cmd))
101 		c->val = perf_config_bool(var, value) ? 2 : 0;
102 	return 0;
103 }
104 
105 /*
106  * returns 0 for "no tui", 1 for "use tui", 2 for "use gtk",
107  * and -1 for "not specified"
108  */
109 static int check_browser_config(const char *cmd)
110 {
111 	struct pager_config c;
112 	c.cmd = cmd;
113 	c.val = -1;
114 	perf_config(browser_command_config, &c);
115 	return c.val;
116 }
117 
118 static void commit_pager_choice(void)
119 {
120 	switch (use_pager) {
121 	case 0:
122 		setenv(PERF_PAGER_ENVIRONMENT, "cat", 1);
123 		break;
124 	case 1:
125 		/* setup_pager(); */
126 		break;
127 	default:
128 		break;
129 	}
130 }
131 
132 struct option options[] = {
133 	OPT_ARGUMENT("help", "help"),
134 	OPT_ARGUMENT("version", "version"),
135 	OPT_ARGUMENT("exec-path", "exec-path"),
136 	OPT_ARGUMENT("html-path", "html-path"),
137 	OPT_ARGUMENT("paginate", "paginate"),
138 	OPT_ARGUMENT("no-pager", "no-pager"),
139 	OPT_ARGUMENT("perf-dir", "perf-dir"),
140 	OPT_ARGUMENT("work-tree", "work-tree"),
141 	OPT_ARGUMENT("debugfs-dir", "debugfs-dir"),
142 	OPT_ARGUMENT("buildid-dir", "buildid-dir"),
143 	OPT_ARGUMENT("list-cmds", "list-cmds"),
144 	OPT_ARGUMENT("list-opts", "list-opts"),
145 	OPT_ARGUMENT("debug", "debug"),
146 	OPT_END()
147 };
148 
149 static int handle_options(const char ***argv, int *argc, int *envchanged)
150 {
151 	int handled = 0;
152 
153 	while (*argc > 0) {
154 		const char *cmd = (*argv)[0];
155 		if (cmd[0] != '-')
156 			break;
157 
158 		/*
159 		 * For legacy reasons, the "version" and "help"
160 		 * commands can be written with "--" prepended
161 		 * to make them look like flags.
162 		 */
163 		if (!strcmp(cmd, "--help") || !strcmp(cmd, "--version"))
164 			break;
165 
166 		/*
167 		 * Shortcut for '-h' and '-v' options to invoke help
168 		 * and version command.
169 		 */
170 		if (!strcmp(cmd, "-h")) {
171 			(*argv)[0] = "--help";
172 			break;
173 		}
174 
175 		if (!strcmp(cmd, "-v")) {
176 			(*argv)[0] = "--version";
177 			break;
178 		}
179 
180 		/*
181 		 * Check remaining flags.
182 		 */
183 		if (!prefixcmp(cmd, CMD_EXEC_PATH)) {
184 			cmd += strlen(CMD_EXEC_PATH);
185 			if (*cmd == '=')
186 				set_argv_exec_path(cmd + 1);
187 			else {
188 				puts(get_argv_exec_path());
189 				exit(0);
190 			}
191 		} else if (!strcmp(cmd, "--html-path")) {
192 			puts(system_path(PERF_HTML_PATH));
193 			exit(0);
194 		} else if (!strcmp(cmd, "-p") || !strcmp(cmd, "--paginate")) {
195 			use_pager = 1;
196 		} else if (!strcmp(cmd, "--no-pager")) {
197 			use_pager = 0;
198 			if (envchanged)
199 				*envchanged = 1;
200 		} else if (!strcmp(cmd, "--perf-dir")) {
201 			if (*argc < 2) {
202 				fprintf(stderr, "No directory given for --perf-dir.\n");
203 				usage(perf_usage_string);
204 			}
205 			setenv(PERF_DIR_ENVIRONMENT, (*argv)[1], 1);
206 			if (envchanged)
207 				*envchanged = 1;
208 			(*argv)++;
209 			(*argc)--;
210 			handled++;
211 		} else if (!prefixcmp(cmd, CMD_PERF_DIR)) {
212 			setenv(PERF_DIR_ENVIRONMENT, cmd + strlen(CMD_PERF_DIR), 1);
213 			if (envchanged)
214 				*envchanged = 1;
215 		} else if (!strcmp(cmd, "--work-tree")) {
216 			if (*argc < 2) {
217 				fprintf(stderr, "No directory given for --work-tree.\n");
218 				usage(perf_usage_string);
219 			}
220 			setenv(PERF_WORK_TREE_ENVIRONMENT, (*argv)[1], 1);
221 			if (envchanged)
222 				*envchanged = 1;
223 			(*argv)++;
224 			(*argc)--;
225 		} else if (!prefixcmp(cmd, CMD_WORK_TREE)) {
226 			setenv(PERF_WORK_TREE_ENVIRONMENT, cmd + strlen(CMD_WORK_TREE), 1);
227 			if (envchanged)
228 				*envchanged = 1;
229 		} else if (!strcmp(cmd, "--debugfs-dir")) {
230 			if (*argc < 2) {
231 				fprintf(stderr, "No directory given for --debugfs-dir.\n");
232 				usage(perf_usage_string);
233 			}
234 			tracing_path_set((*argv)[1]);
235 			if (envchanged)
236 				*envchanged = 1;
237 			(*argv)++;
238 			(*argc)--;
239 		} else if (!strcmp(cmd, "--buildid-dir")) {
240 			if (*argc < 2) {
241 				fprintf(stderr, "No directory given for --buildid-dir.\n");
242 				usage(perf_usage_string);
243 			}
244 			set_buildid_dir((*argv)[1]);
245 			if (envchanged)
246 				*envchanged = 1;
247 			(*argv)++;
248 			(*argc)--;
249 		} else if (!prefixcmp(cmd, CMD_DEBUGFS_DIR)) {
250 			tracing_path_set(cmd + strlen(CMD_DEBUGFS_DIR));
251 			fprintf(stderr, "dir: %s\n", tracing_path);
252 			if (envchanged)
253 				*envchanged = 1;
254 		} else if (!strcmp(cmd, "--list-cmds")) {
255 			unsigned int i;
256 
257 			for (i = 0; i < ARRAY_SIZE(commands); i++) {
258 				struct cmd_struct *p = commands+i;
259 				printf("%s ", p->cmd);
260 			}
261 			putchar('\n');
262 			exit(0);
263 		} else if (!strcmp(cmd, "--list-opts")) {
264 			unsigned int i;
265 
266 			for (i = 0; i < ARRAY_SIZE(options)-1; i++) {
267 				struct option *p = options+i;
268 				printf("--%s ", p->long_name);
269 			}
270 			putchar('\n');
271 			exit(0);
272 		} else if (!strcmp(cmd, "--debug")) {
273 			if (*argc < 2) {
274 				fprintf(stderr, "No variable specified for --debug.\n");
275 				usage(perf_usage_string);
276 			}
277 			if (perf_debug_option((*argv)[1]))
278 				usage(perf_usage_string);
279 
280 			(*argv)++;
281 			(*argc)--;
282 		} else {
283 			fprintf(stderr, "Unknown option: %s\n", cmd);
284 			usage(perf_usage_string);
285 		}
286 
287 		(*argv)++;
288 		(*argc)--;
289 		handled++;
290 	}
291 	return handled;
292 }
293 
294 static int handle_alias(int *argcp, const char ***argv)
295 {
296 	int envchanged = 0, ret = 0, saved_errno = errno;
297 	int count, option_count;
298 	const char **new_argv;
299 	const char *alias_command;
300 	char *alias_string;
301 
302 	alias_command = (*argv)[0];
303 	alias_string = alias_lookup(alias_command);
304 	if (alias_string) {
305 		if (alias_string[0] == '!') {
306 			if (*argcp > 1) {
307 				struct strbuf buf;
308 
309 				strbuf_init(&buf, PATH_MAX);
310 				strbuf_addstr(&buf, alias_string);
311 				sq_quote_argv(&buf, (*argv) + 1, PATH_MAX);
312 				free(alias_string);
313 				alias_string = buf.buf;
314 			}
315 			ret = system(alias_string + 1);
316 			if (ret >= 0 && WIFEXITED(ret) &&
317 			    WEXITSTATUS(ret) != 127)
318 				exit(WEXITSTATUS(ret));
319 			die("Failed to run '%s' when expanding alias '%s'",
320 			    alias_string + 1, alias_command);
321 		}
322 		count = split_cmdline(alias_string, &new_argv);
323 		if (count < 0)
324 			die("Bad alias.%s string", alias_command);
325 		option_count = handle_options(&new_argv, &count, &envchanged);
326 		if (envchanged)
327 			die("alias '%s' changes environment variables\n"
328 				 "You can use '!perf' in the alias to do this.",
329 				 alias_command);
330 		memmove(new_argv - option_count, new_argv,
331 				count * sizeof(char *));
332 		new_argv -= option_count;
333 
334 		if (count < 1)
335 			die("empty alias for %s", alias_command);
336 
337 		if (!strcmp(alias_command, new_argv[0]))
338 			die("recursive alias: %s", alias_command);
339 
340 		new_argv = realloc(new_argv, sizeof(char *) *
341 				    (count + *argcp + 1));
342 		/* insert after command name */
343 		memcpy(new_argv + count, *argv + 1, sizeof(char *) * *argcp);
344 		new_argv[count + *argcp] = NULL;
345 
346 		*argv = new_argv;
347 		*argcp += count - 1;
348 
349 		ret = 1;
350 	}
351 
352 	errno = saved_errno;
353 
354 	return ret;
355 }
356 
357 const char perf_version_string[] = PERF_VERSION;
358 
359 #define RUN_SETUP	(1<<0)
360 #define USE_PAGER	(1<<1)
361 /*
362  * require working tree to be present -- anything uses this needs
363  * RUN_SETUP for reading from the configuration file.
364  */
365 #define NEED_WORK_TREE	(1<<2)
366 
367 static int run_builtin(struct cmd_struct *p, int argc, const char **argv)
368 {
369 	int status;
370 	struct stat st;
371 	const char *prefix;
372 	char sbuf[STRERR_BUFSIZE];
373 
374 	prefix = NULL;
375 	if (p->option & RUN_SETUP)
376 		prefix = NULL; /* setup_perf_directory(); */
377 
378 	if (use_browser == -1)
379 		use_browser = check_browser_config(p->cmd);
380 
381 	if (use_pager == -1 && p->option & RUN_SETUP)
382 		use_pager = check_pager_config(p->cmd);
383 	if (use_pager == -1 && p->option & USE_PAGER)
384 		use_pager = 1;
385 	commit_pager_choice();
386 
387 	perf_env__set_cmdline(&perf_env, argc, argv);
388 	status = p->fn(argc, argv, prefix);
389 	exit_browser(status);
390 	perf_env__exit(&perf_env);
391 	bpf__clear();
392 
393 	if (status)
394 		return status & 0xff;
395 
396 	/* Somebody closed stdout? */
397 	if (fstat(fileno(stdout), &st))
398 		return 0;
399 	/* Ignore write errors for pipes and sockets.. */
400 	if (S_ISFIFO(st.st_mode) || S_ISSOCK(st.st_mode))
401 		return 0;
402 
403 	status = 1;
404 	/* Check for ENOSPC and EIO errors.. */
405 	if (fflush(stdout)) {
406 		fprintf(stderr, "write failure on standard output: %s",
407 			strerror_r(errno, sbuf, sizeof(sbuf)));
408 		goto out;
409 	}
410 	if (ferror(stdout)) {
411 		fprintf(stderr, "unknown write failure on standard output");
412 		goto out;
413 	}
414 	if (fclose(stdout)) {
415 		fprintf(stderr, "close failed on standard output: %s",
416 			strerror_r(errno, sbuf, sizeof(sbuf)));
417 		goto out;
418 	}
419 	status = 0;
420 out:
421 	return status;
422 }
423 
424 static void handle_internal_command(int argc, const char **argv)
425 {
426 	const char *cmd = argv[0];
427 	unsigned int i;
428 	static const char ext[] = STRIP_EXTENSION;
429 
430 	if (sizeof(ext) > 1) {
431 		i = strlen(argv[0]) - strlen(ext);
432 		if (i > 0 && !strcmp(argv[0] + i, ext)) {
433 			char *argv0 = strdup(argv[0]);
434 			argv[0] = cmd = argv0;
435 			argv0[i] = '\0';
436 		}
437 	}
438 
439 	/* Turn "perf cmd --help" into "perf help cmd" */
440 	if (argc > 1 && !strcmp(argv[1], "--help")) {
441 		argv[1] = argv[0];
442 		argv[0] = cmd = "help";
443 	}
444 
445 	for (i = 0; i < ARRAY_SIZE(commands); i++) {
446 		struct cmd_struct *p = commands+i;
447 		if (strcmp(p->cmd, cmd))
448 			continue;
449 		exit(run_builtin(p, argc, argv));
450 	}
451 }
452 
453 static void execv_dashed_external(const char **argv)
454 {
455 	struct strbuf cmd = STRBUF_INIT;
456 	const char *tmp;
457 	int status;
458 
459 	strbuf_addf(&cmd, "perf-%s", argv[0]);
460 
461 	/*
462 	 * argv[0] must be the perf command, but the argv array
463 	 * belongs to the caller, and may be reused in
464 	 * subsequent loop iterations. Save argv[0] and
465 	 * restore it on error.
466 	 */
467 	tmp = argv[0];
468 	argv[0] = cmd.buf;
469 
470 	/*
471 	 * if we fail because the command is not found, it is
472 	 * OK to return. Otherwise, we just pass along the status code.
473 	 */
474 	status = run_command_v_opt(argv, 0);
475 	if (status != -ERR_RUN_COMMAND_EXEC) {
476 		if (IS_RUN_COMMAND_ERR(status))
477 			die("unable to run '%s'", argv[0]);
478 		exit(-status);
479 	}
480 	errno = ENOENT; /* as if we called execvp */
481 
482 	argv[0] = tmp;
483 
484 	strbuf_release(&cmd);
485 }
486 
487 static int run_argv(int *argcp, const char ***argv)
488 {
489 	int done_alias = 0;
490 
491 	while (1) {
492 		/* See if it's an internal command */
493 		handle_internal_command(*argcp, *argv);
494 
495 		/* .. then try the external ones */
496 		execv_dashed_external(*argv);
497 
498 		/* It could be an alias -- this works around the insanity
499 		 * of overriding "perf log" with "perf show" by having
500 		 * alias.log = show
501 		 */
502 		if (done_alias || !handle_alias(argcp, argv))
503 			break;
504 		done_alias = 1;
505 	}
506 
507 	return done_alias;
508 }
509 
510 static void pthread__block_sigwinch(void)
511 {
512 	sigset_t set;
513 
514 	sigemptyset(&set);
515 	sigaddset(&set, SIGWINCH);
516 	pthread_sigmask(SIG_BLOCK, &set, NULL);
517 }
518 
519 void pthread__unblock_sigwinch(void)
520 {
521 	sigset_t set;
522 
523 	sigemptyset(&set);
524 	sigaddset(&set, SIGWINCH);
525 	pthread_sigmask(SIG_UNBLOCK, &set, NULL);
526 }
527 
528 int main(int argc, const char **argv)
529 {
530 	const char *cmd;
531 	char sbuf[STRERR_BUFSIZE];
532 
533 	/* libsubcmd init */
534 	exec_cmd_init("perf", PREFIX, PERF_EXEC_PATH, EXEC_PATH_ENVIRONMENT);
535 	pager_init(PERF_PAGER_ENVIRONMENT);
536 
537 	/* The page_size is placed in util object. */
538 	page_size = sysconf(_SC_PAGE_SIZE);
539 	cacheline_size = sysconf(_SC_LEVEL1_DCACHE_LINESIZE);
540 
541 	cmd = extract_argv0_path(argv[0]);
542 	if (!cmd)
543 		cmd = "perf-help";
544 
545 	/* get debugfs/tracefs mount point from /proc/mounts */
546 	tracing_path_mount();
547 
548 	/*
549 	 * "perf-xxxx" is the same as "perf xxxx", but we obviously:
550 	 *
551 	 *  - cannot take flags in between the "perf" and the "xxxx".
552 	 *  - cannot execute it externally (since it would just do
553 	 *    the same thing over again)
554 	 *
555 	 * So we just directly call the internal command handler, and
556 	 * die if that one cannot handle it.
557 	 */
558 	if (!prefixcmp(cmd, "perf-")) {
559 		cmd += 5;
560 		argv[0] = cmd;
561 		handle_internal_command(argc, argv);
562 		fprintf(stderr, "cannot handle %s internally", cmd);
563 		goto out;
564 	}
565 	if (!prefixcmp(cmd, "trace")) {
566 #ifdef HAVE_LIBAUDIT_SUPPORT
567 		set_buildid_dir(NULL);
568 		setup_path();
569 		argv[0] = "trace";
570 		return cmd_trace(argc, argv, NULL);
571 #else
572 		fprintf(stderr,
573 			"trace command not available: missing audit-libs devel package at build time.\n");
574 		goto out;
575 #endif
576 	}
577 	/* Look for flags.. */
578 	argv++;
579 	argc--;
580 	handle_options(&argv, &argc, NULL);
581 	commit_pager_choice();
582 	set_buildid_dir(NULL);
583 
584 	if (argc > 0) {
585 		if (!prefixcmp(argv[0], "--"))
586 			argv[0] += 2;
587 	} else {
588 		/* The user didn't specify a command; give them help */
589 		printf("\n usage: %s\n\n", perf_usage_string);
590 		list_common_cmds_help();
591 		printf("\n %s\n\n", perf_more_info_string);
592 		goto out;
593 	}
594 	cmd = argv[0];
595 
596 	test_attr__init();
597 
598 	/*
599 	 * We use PATH to find perf commands, but we prepend some higher
600 	 * precedence paths: the "--exec-path" option, the PERF_EXEC_PATH
601 	 * environment, and the $(perfexecdir) from the Makefile at build
602 	 * time.
603 	 */
604 	setup_path();
605 	/*
606 	 * Block SIGWINCH notifications so that the thread that wants it can
607 	 * unblock and get syscalls like select interrupted instead of waiting
608 	 * forever while the signal goes to some other non interested thread.
609 	 */
610 	pthread__block_sigwinch();
611 
612 	while (1) {
613 		static int done_help;
614 		int was_alias = run_argv(&argc, &argv);
615 
616 		if (errno != ENOENT)
617 			break;
618 
619 		if (was_alias) {
620 			fprintf(stderr, "Expansion of alias '%s' failed; "
621 				"'%s' is not a perf-command\n",
622 				cmd, argv[0]);
623 			goto out;
624 		}
625 		if (!done_help) {
626 			cmd = argv[0] = help_unknown_cmd(cmd);
627 			done_help = 1;
628 		} else
629 			break;
630 	}
631 
632 	fprintf(stderr, "Failed to run command '%s': %s\n",
633 		cmd, strerror_r(errno, sbuf, sizeof(sbuf)));
634 out:
635 	return 1;
636 }
637