xref: /openbmc/linux/tools/perf/perf.c (revision 3805e6a1)
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/fs.h>
21 #include <api/fs/tracing_path.h>
22 #include <pthread.h>
23 #include <stdlib.h>
24 #include <time.h>
25 
26 const char perf_usage_string[] =
27 	"perf [--version] [--help] [OPTIONS] COMMAND [ARGS]";
28 
29 const char perf_more_info_string[] =
30 	"See 'perf help COMMAND' for more information on a specific command.";
31 
32 int use_browser = -1;
33 static int use_pager = -1;
34 const char *input_name;
35 
36 struct cmd_struct {
37 	const char *cmd;
38 	int (*fn)(int, const char **, const char *);
39 	int option;
40 };
41 
42 static struct cmd_struct commands[] = {
43 	{ "buildid-cache", cmd_buildid_cache, 0 },
44 	{ "buildid-list", cmd_buildid_list, 0 },
45 	{ "config",	cmd_config,	0 },
46 	{ "diff",	cmd_diff,	0 },
47 	{ "evlist",	cmd_evlist,	0 },
48 	{ "help",	cmd_help,	0 },
49 	{ "list",	cmd_list,	0 },
50 	{ "record",	cmd_record,	0 },
51 	{ "report",	cmd_report,	0 },
52 	{ "bench",	cmd_bench,	0 },
53 	{ "stat",	cmd_stat,	0 },
54 	{ "timechart",	cmd_timechart,	0 },
55 	{ "top",	cmd_top,	0 },
56 	{ "annotate",	cmd_annotate,	0 },
57 	{ "version",	cmd_version,	0 },
58 	{ "script",	cmd_script,	0 },
59 	{ "sched",	cmd_sched,	0 },
60 #ifdef HAVE_LIBELF_SUPPORT
61 	{ "probe",	cmd_probe,	0 },
62 #endif
63 	{ "kmem",	cmd_kmem,	0 },
64 	{ "lock",	cmd_lock,	0 },
65 	{ "kvm",	cmd_kvm,	0 },
66 	{ "test",	cmd_test,	0 },
67 #ifdef HAVE_LIBAUDIT_SUPPORT
68 	{ "trace",	cmd_trace,	0 },
69 #endif
70 	{ "inject",	cmd_inject,	0 },
71 	{ "mem",	cmd_mem,	0 },
72 	{ "data",	cmd_data,	0 },
73 };
74 
75 struct pager_config {
76 	const char *cmd;
77 	int val;
78 };
79 
80 static int pager_command_config(const char *var, const char *value, void *data)
81 {
82 	struct pager_config *c = data;
83 	if (!prefixcmp(var, "pager.") && !strcmp(var + 6, c->cmd))
84 		c->val = perf_config_bool(var, value);
85 	return 0;
86 }
87 
88 /* returns 0 for "no pager", 1 for "use pager", and -1 for "not specified" */
89 int check_pager_config(const char *cmd)
90 {
91 	struct pager_config c;
92 	c.cmd = cmd;
93 	c.val = -1;
94 	perf_config(pager_command_config, &c);
95 	return c.val;
96 }
97 
98 static int browser_command_config(const char *var, const char *value, void *data)
99 {
100 	struct pager_config *c = data;
101 	if (!prefixcmp(var, "tui.") && !strcmp(var + 4, c->cmd))
102 		c->val = perf_config_bool(var, value);
103 	if (!prefixcmp(var, "gtk.") && !strcmp(var + 4, c->cmd))
104 		c->val = perf_config_bool(var, value) ? 2 : 0;
105 	return 0;
106 }
107 
108 /*
109  * returns 0 for "no tui", 1 for "use tui", 2 for "use gtk",
110  * and -1 for "not specified"
111  */
112 static int check_browser_config(const char *cmd)
113 {
114 	struct pager_config c;
115 	c.cmd = cmd;
116 	c.val = -1;
117 	perf_config(browser_command_config, &c);
118 	return c.val;
119 }
120 
121 static void commit_pager_choice(void)
122 {
123 	switch (use_pager) {
124 	case 0:
125 		setenv(PERF_PAGER_ENVIRONMENT, "cat", 1);
126 		break;
127 	case 1:
128 		/* setup_pager(); */
129 		break;
130 	default:
131 		break;
132 	}
133 }
134 
135 struct option options[] = {
136 	OPT_ARGUMENT("help", "help"),
137 	OPT_ARGUMENT("version", "version"),
138 	OPT_ARGUMENT("exec-path", "exec-path"),
139 	OPT_ARGUMENT("html-path", "html-path"),
140 	OPT_ARGUMENT("paginate", "paginate"),
141 	OPT_ARGUMENT("no-pager", "no-pager"),
142 	OPT_ARGUMENT("perf-dir", "perf-dir"),
143 	OPT_ARGUMENT("work-tree", "work-tree"),
144 	OPT_ARGUMENT("debugfs-dir", "debugfs-dir"),
145 	OPT_ARGUMENT("buildid-dir", "buildid-dir"),
146 	OPT_ARGUMENT("list-cmds", "list-cmds"),
147 	OPT_ARGUMENT("list-opts", "list-opts"),
148 	OPT_ARGUMENT("debug", "debug"),
149 	OPT_END()
150 };
151 
152 static int handle_options(const char ***argv, int *argc, int *envchanged)
153 {
154 	int handled = 0;
155 
156 	while (*argc > 0) {
157 		const char *cmd = (*argv)[0];
158 		if (cmd[0] != '-')
159 			break;
160 
161 		/*
162 		 * For legacy reasons, the "version" and "help"
163 		 * commands can be written with "--" prepended
164 		 * to make them look like flags.
165 		 */
166 		if (!strcmp(cmd, "--help") || !strcmp(cmd, "--version"))
167 			break;
168 
169 		/*
170 		 * Shortcut for '-h' and '-v' options to invoke help
171 		 * and version command.
172 		 */
173 		if (!strcmp(cmd, "-h")) {
174 			(*argv)[0] = "--help";
175 			break;
176 		}
177 
178 		if (!strcmp(cmd, "-v")) {
179 			(*argv)[0] = "--version";
180 			break;
181 		}
182 
183 		/*
184 		 * Check remaining flags.
185 		 */
186 		if (!prefixcmp(cmd, CMD_EXEC_PATH)) {
187 			cmd += strlen(CMD_EXEC_PATH);
188 			if (*cmd == '=')
189 				set_argv_exec_path(cmd + 1);
190 			else {
191 				puts(get_argv_exec_path());
192 				exit(0);
193 			}
194 		} else if (!strcmp(cmd, "--html-path")) {
195 			puts(system_path(PERF_HTML_PATH));
196 			exit(0);
197 		} else if (!strcmp(cmd, "-p") || !strcmp(cmd, "--paginate")) {
198 			use_pager = 1;
199 		} else if (!strcmp(cmd, "--no-pager")) {
200 			use_pager = 0;
201 			if (envchanged)
202 				*envchanged = 1;
203 		} else if (!strcmp(cmd, "--perf-dir")) {
204 			if (*argc < 2) {
205 				fprintf(stderr, "No directory given for --perf-dir.\n");
206 				usage(perf_usage_string);
207 			}
208 			setenv(PERF_DIR_ENVIRONMENT, (*argv)[1], 1);
209 			if (envchanged)
210 				*envchanged = 1;
211 			(*argv)++;
212 			(*argc)--;
213 			handled++;
214 		} else if (!prefixcmp(cmd, CMD_PERF_DIR)) {
215 			setenv(PERF_DIR_ENVIRONMENT, cmd + strlen(CMD_PERF_DIR), 1);
216 			if (envchanged)
217 				*envchanged = 1;
218 		} else if (!strcmp(cmd, "--work-tree")) {
219 			if (*argc < 2) {
220 				fprintf(stderr, "No directory given for --work-tree.\n");
221 				usage(perf_usage_string);
222 			}
223 			setenv(PERF_WORK_TREE_ENVIRONMENT, (*argv)[1], 1);
224 			if (envchanged)
225 				*envchanged = 1;
226 			(*argv)++;
227 			(*argc)--;
228 		} else if (!prefixcmp(cmd, CMD_WORK_TREE)) {
229 			setenv(PERF_WORK_TREE_ENVIRONMENT, cmd + strlen(CMD_WORK_TREE), 1);
230 			if (envchanged)
231 				*envchanged = 1;
232 		} else if (!strcmp(cmd, "--debugfs-dir")) {
233 			if (*argc < 2) {
234 				fprintf(stderr, "No directory given for --debugfs-dir.\n");
235 				usage(perf_usage_string);
236 			}
237 			tracing_path_set((*argv)[1]);
238 			if (envchanged)
239 				*envchanged = 1;
240 			(*argv)++;
241 			(*argc)--;
242 		} else if (!strcmp(cmd, "--buildid-dir")) {
243 			if (*argc < 2) {
244 				fprintf(stderr, "No directory given for --buildid-dir.\n");
245 				usage(perf_usage_string);
246 			}
247 			set_buildid_dir((*argv)[1]);
248 			if (envchanged)
249 				*envchanged = 1;
250 			(*argv)++;
251 			(*argc)--;
252 		} else if (!prefixcmp(cmd, CMD_DEBUGFS_DIR)) {
253 			tracing_path_set(cmd + strlen(CMD_DEBUGFS_DIR));
254 			fprintf(stderr, "dir: %s\n", tracing_path);
255 			if (envchanged)
256 				*envchanged = 1;
257 		} else if (!strcmp(cmd, "--list-cmds")) {
258 			unsigned int i;
259 
260 			for (i = 0; i < ARRAY_SIZE(commands); i++) {
261 				struct cmd_struct *p = commands+i;
262 				printf("%s ", p->cmd);
263 			}
264 			putchar('\n');
265 			exit(0);
266 		} else if (!strcmp(cmd, "--list-opts")) {
267 			unsigned int i;
268 
269 			for (i = 0; i < ARRAY_SIZE(options)-1; i++) {
270 				struct option *p = options+i;
271 				printf("--%s ", p->long_name);
272 			}
273 			putchar('\n');
274 			exit(0);
275 		} else if (!strcmp(cmd, "--debug")) {
276 			if (*argc < 2) {
277 				fprintf(stderr, "No variable specified for --debug.\n");
278 				usage(perf_usage_string);
279 			}
280 			if (perf_debug_option((*argv)[1]))
281 				usage(perf_usage_string);
282 
283 			(*argv)++;
284 			(*argc)--;
285 		} else {
286 			fprintf(stderr, "Unknown option: %s\n", cmd);
287 			usage(perf_usage_string);
288 		}
289 
290 		(*argv)++;
291 		(*argc)--;
292 		handled++;
293 	}
294 	return handled;
295 }
296 
297 static int handle_alias(int *argcp, const char ***argv)
298 {
299 	int envchanged = 0, ret = 0, saved_errno = errno;
300 	int count, option_count;
301 	const char **new_argv;
302 	const char *alias_command;
303 	char *alias_string;
304 
305 	alias_command = (*argv)[0];
306 	alias_string = alias_lookup(alias_command);
307 	if (alias_string) {
308 		if (alias_string[0] == '!') {
309 			if (*argcp > 1) {
310 				struct strbuf buf;
311 
312 				if (strbuf_init(&buf, PATH_MAX) < 0 ||
313 				    strbuf_addstr(&buf, alias_string) < 0 ||
314 				    sq_quote_argv(&buf, (*argv) + 1,
315 						  PATH_MAX) < 0)
316 					die("Failed to allocate memory.");
317 				free(alias_string);
318 				alias_string = buf.buf;
319 			}
320 			ret = system(alias_string + 1);
321 			if (ret >= 0 && WIFEXITED(ret) &&
322 			    WEXITSTATUS(ret) != 127)
323 				exit(WEXITSTATUS(ret));
324 			die("Failed to run '%s' when expanding alias '%s'",
325 			    alias_string + 1, alias_command);
326 		}
327 		count = split_cmdline(alias_string, &new_argv);
328 		if (count < 0)
329 			die("Bad alias.%s string", alias_command);
330 		option_count = handle_options(&new_argv, &count, &envchanged);
331 		if (envchanged)
332 			die("alias '%s' changes environment variables\n"
333 				 "You can use '!perf' in the alias to do this.",
334 				 alias_command);
335 		memmove(new_argv - option_count, new_argv,
336 				count * sizeof(char *));
337 		new_argv -= option_count;
338 
339 		if (count < 1)
340 			die("empty alias for %s", alias_command);
341 
342 		if (!strcmp(alias_command, new_argv[0]))
343 			die("recursive alias: %s", alias_command);
344 
345 		new_argv = realloc(new_argv, sizeof(char *) *
346 				    (count + *argcp + 1));
347 		/* insert after command name */
348 		memcpy(new_argv + count, *argv + 1, sizeof(char *) * *argcp);
349 		new_argv[count + *argcp] = NULL;
350 
351 		*argv = new_argv;
352 		*argcp += count - 1;
353 
354 		ret = 1;
355 	}
356 
357 	errno = saved_errno;
358 
359 	return ret;
360 }
361 
362 const char perf_version_string[] = PERF_VERSION;
363 
364 #define RUN_SETUP	(1<<0)
365 #define USE_PAGER	(1<<1)
366 /*
367  * require working tree to be present -- anything uses this needs
368  * RUN_SETUP for reading from the configuration file.
369  */
370 #define NEED_WORK_TREE	(1<<2)
371 
372 static int run_builtin(struct cmd_struct *p, int argc, const char **argv)
373 {
374 	int status;
375 	struct stat st;
376 	const char *prefix;
377 	char sbuf[STRERR_BUFSIZE];
378 
379 	prefix = NULL;
380 	if (p->option & RUN_SETUP)
381 		prefix = NULL; /* setup_perf_directory(); */
382 
383 	if (use_browser == -1)
384 		use_browser = check_browser_config(p->cmd);
385 
386 	if (use_pager == -1 && p->option & RUN_SETUP)
387 		use_pager = check_pager_config(p->cmd);
388 	if (use_pager == -1 && p->option & USE_PAGER)
389 		use_pager = 1;
390 	commit_pager_choice();
391 
392 	perf_env__set_cmdline(&perf_env, argc, argv);
393 	status = p->fn(argc, argv, prefix);
394 	exit_browser(status);
395 	perf_env__exit(&perf_env);
396 	bpf__clear();
397 
398 	if (status)
399 		return status & 0xff;
400 
401 	/* Somebody closed stdout? */
402 	if (fstat(fileno(stdout), &st))
403 		return 0;
404 	/* Ignore write errors for pipes and sockets.. */
405 	if (S_ISFIFO(st.st_mode) || S_ISSOCK(st.st_mode))
406 		return 0;
407 
408 	status = 1;
409 	/* Check for ENOSPC and EIO errors.. */
410 	if (fflush(stdout)) {
411 		fprintf(stderr, "write failure on standard output: %s",
412 			strerror_r(errno, sbuf, sizeof(sbuf)));
413 		goto out;
414 	}
415 	if (ferror(stdout)) {
416 		fprintf(stderr, "unknown write failure on standard output");
417 		goto out;
418 	}
419 	if (fclose(stdout)) {
420 		fprintf(stderr, "close failed on standard output: %s",
421 			strerror_r(errno, sbuf, sizeof(sbuf)));
422 		goto out;
423 	}
424 	status = 0;
425 out:
426 	return status;
427 }
428 
429 static void handle_internal_command(int argc, const char **argv)
430 {
431 	const char *cmd = argv[0];
432 	unsigned int i;
433 	static const char ext[] = STRIP_EXTENSION;
434 
435 	if (sizeof(ext) > 1) {
436 		i = strlen(argv[0]) - strlen(ext);
437 		if (i > 0 && !strcmp(argv[0] + i, ext)) {
438 			char *argv0 = strdup(argv[0]);
439 			argv[0] = cmd = argv0;
440 			argv0[i] = '\0';
441 		}
442 	}
443 
444 	/* Turn "perf cmd --help" into "perf help cmd" */
445 	if (argc > 1 && !strcmp(argv[1], "--help")) {
446 		argv[1] = argv[0];
447 		argv[0] = cmd = "help";
448 	}
449 
450 	for (i = 0; i < ARRAY_SIZE(commands); i++) {
451 		struct cmd_struct *p = commands+i;
452 		if (strcmp(p->cmd, cmd))
453 			continue;
454 		exit(run_builtin(p, argc, argv));
455 	}
456 }
457 
458 static void execv_dashed_external(const char **argv)
459 {
460 	char *cmd;
461 	const char *tmp;
462 	int status;
463 
464 	if (asprintf(&cmd, "perf-%s", argv[0]) < 0)
465 		goto do_die;
466 
467 	/*
468 	 * argv[0] must be the perf command, but the argv array
469 	 * belongs to the caller, and may be reused in
470 	 * subsequent loop iterations. Save argv[0] and
471 	 * restore it on error.
472 	 */
473 	tmp = argv[0];
474 	argv[0] = cmd;
475 
476 	/*
477 	 * if we fail because the command is not found, it is
478 	 * OK to return. Otherwise, we just pass along the status code.
479 	 */
480 	status = run_command_v_opt(argv, 0);
481 	if (status != -ERR_RUN_COMMAND_EXEC) {
482 		if (IS_RUN_COMMAND_ERR(status)) {
483 do_die:
484 			die("unable to run '%s'", argv[0]);
485 		}
486 		exit(-status);
487 	}
488 	errno = ENOENT; /* as if we called execvp */
489 
490 	argv[0] = tmp;
491 	zfree(&cmd);
492 }
493 
494 static int run_argv(int *argcp, const char ***argv)
495 {
496 	int done_alias = 0;
497 
498 	while (1) {
499 		/* See if it's an internal command */
500 		handle_internal_command(*argcp, *argv);
501 
502 		/* .. then try the external ones */
503 		execv_dashed_external(*argv);
504 
505 		/* It could be an alias -- this works around the insanity
506 		 * of overriding "perf log" with "perf show" by having
507 		 * alias.log = show
508 		 */
509 		if (done_alias || !handle_alias(argcp, argv))
510 			break;
511 		done_alias = 1;
512 	}
513 
514 	return done_alias;
515 }
516 
517 static void pthread__block_sigwinch(void)
518 {
519 	sigset_t set;
520 
521 	sigemptyset(&set);
522 	sigaddset(&set, SIGWINCH);
523 	pthread_sigmask(SIG_BLOCK, &set, NULL);
524 }
525 
526 void pthread__unblock_sigwinch(void)
527 {
528 	sigset_t set;
529 
530 	sigemptyset(&set);
531 	sigaddset(&set, SIGWINCH);
532 	pthread_sigmask(SIG_UNBLOCK, &set, NULL);
533 }
534 
535 int main(int argc, const char **argv)
536 {
537 	const char *cmd;
538 	char sbuf[STRERR_BUFSIZE];
539 	int value;
540 
541 	/* libsubcmd init */
542 	exec_cmd_init("perf", PREFIX, PERF_EXEC_PATH, EXEC_PATH_ENVIRONMENT);
543 	pager_init(PERF_PAGER_ENVIRONMENT);
544 
545 	/* The page_size is placed in util object. */
546 	page_size = sysconf(_SC_PAGE_SIZE);
547 	cacheline_size = sysconf(_SC_LEVEL1_DCACHE_LINESIZE);
548 
549 	if (sysctl__read_int("kernel/perf_event_max_stack", &value) == 0)
550 		sysctl_perf_event_max_stack = value;
551 
552 	if (sysctl__read_int("kernel/perf_event_max_contexts_per_stack", &value) == 0)
553 		sysctl_perf_event_max_contexts_per_stack = value;
554 
555 	cmd = extract_argv0_path(argv[0]);
556 	if (!cmd)
557 		cmd = "perf-help";
558 
559 	srandom(time(NULL));
560 
561 	perf_config(perf_default_config, NULL);
562 	set_buildid_dir(NULL);
563 
564 	/* get debugfs/tracefs mount point from /proc/mounts */
565 	tracing_path_mount();
566 
567 	/*
568 	 * "perf-xxxx" is the same as "perf xxxx", but we obviously:
569 	 *
570 	 *  - cannot take flags in between the "perf" and the "xxxx".
571 	 *  - cannot execute it externally (since it would just do
572 	 *    the same thing over again)
573 	 *
574 	 * So we just directly call the internal command handler, and
575 	 * die if that one cannot handle it.
576 	 */
577 	if (!prefixcmp(cmd, "perf-")) {
578 		cmd += 5;
579 		argv[0] = cmd;
580 		handle_internal_command(argc, argv);
581 		fprintf(stderr, "cannot handle %s internally", cmd);
582 		goto out;
583 	}
584 	if (!prefixcmp(cmd, "trace")) {
585 #ifdef HAVE_LIBAUDIT_SUPPORT
586 		setup_path();
587 		argv[0] = "trace";
588 		return cmd_trace(argc, argv, NULL);
589 #else
590 		fprintf(stderr,
591 			"trace command not available: missing audit-libs devel package at build time.\n");
592 		goto out;
593 #endif
594 	}
595 	/* Look for flags.. */
596 	argv++;
597 	argc--;
598 	handle_options(&argv, &argc, NULL);
599 	commit_pager_choice();
600 
601 	if (argc > 0) {
602 		if (!prefixcmp(argv[0], "--"))
603 			argv[0] += 2;
604 	} else {
605 		/* The user didn't specify a command; give them help */
606 		printf("\n usage: %s\n\n", perf_usage_string);
607 		list_common_cmds_help();
608 		printf("\n %s\n\n", perf_more_info_string);
609 		goto out;
610 	}
611 	cmd = argv[0];
612 
613 	test_attr__init();
614 
615 	/*
616 	 * We use PATH to find perf commands, but we prepend some higher
617 	 * precedence paths: the "--exec-path" option, the PERF_EXEC_PATH
618 	 * environment, and the $(perfexecdir) from the Makefile at build
619 	 * time.
620 	 */
621 	setup_path();
622 	/*
623 	 * Block SIGWINCH notifications so that the thread that wants it can
624 	 * unblock and get syscalls like select interrupted instead of waiting
625 	 * forever while the signal goes to some other non interested thread.
626 	 */
627 	pthread__block_sigwinch();
628 
629 	perf_debug_setup();
630 
631 	while (1) {
632 		static int done_help;
633 		int was_alias = run_argv(&argc, &argv);
634 
635 		if (errno != ENOENT)
636 			break;
637 
638 		if (was_alias) {
639 			fprintf(stderr, "Expansion of alias '%s' failed; "
640 				"'%s' is not a perf-command\n",
641 				cmd, argv[0]);
642 			goto out;
643 		}
644 		if (!done_help) {
645 			cmd = argv[0] = help_unknown_cmd(cmd);
646 			done_help = 1;
647 		} else
648 			break;
649 	}
650 
651 	fprintf(stderr, "Failed to run command '%s': %s\n",
652 		cmd, strerror_r(errno, sbuf, sizeof(sbuf)));
653 out:
654 	return 1;
655 }
656