xref: /linux/tools/perf/perf.c (revision ca55b2fef3a9373fcfc30f82fd26bc7fccbda732) 
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/exec_cmd.h"
12 #include "util/cache.h"
13 #include "util/quote.h"
14 #include "util/run-command.h"
15 #include "util/parse-events.h"
16 #include "util/parse-options.h"
17 #include "util/debug.h"
18 #include <api/fs/debugfs.h>
19 #include <pthread.h>
20 
21 const char perf_usage_string[] =
22 	"perf [--version] [--help] [OPTIONS] COMMAND [ARGS]";
23 
24 const char perf_more_info_string[] =
25 	"See 'perf help COMMAND' for more information on a specific command.";
26 
27 int use_browser = -1;
28 static int use_pager = -1;
29 const char *input_name;
30 
31 struct cmd_struct {
32 	const char *cmd;
33 	int (*fn)(int, const char **, const char *);
34 	int option;
35 };
36 
37 static struct cmd_struct commands[] = {
38 	{ "buildid-cache", cmd_buildid_cache, 0 },
39 	{ "buildid-list", cmd_buildid_list, 0 },
40 	{ "diff",	cmd_diff,	0 },
41 	{ "evlist",	cmd_evlist,	0 },
42 	{ "help",	cmd_help,	0 },
43 	{ "list",	cmd_list,	0 },
44 	{ "record",	cmd_record,	0 },
45 	{ "report",	cmd_report,	0 },
46 	{ "bench",	cmd_bench,	0 },
47 	{ "stat",	cmd_stat,	0 },
48 	{ "timechart",	cmd_timechart,	0 },
49 	{ "top",	cmd_top,	0 },
50 	{ "annotate",	cmd_annotate,	0 },
51 	{ "version",	cmd_version,	0 },
52 	{ "script",	cmd_script,	0 },
53 	{ "sched",	cmd_sched,	0 },
54 #ifdef HAVE_LIBELF_SUPPORT
55 	{ "probe",	cmd_probe,	0 },
56 #endif
57 	{ "kmem",	cmd_kmem,	0 },
58 	{ "lock",	cmd_lock,	0 },
59 	{ "kvm",	cmd_kvm,	0 },
60 	{ "test",	cmd_test,	0 },
61 #ifdef HAVE_LIBAUDIT_SUPPORT
62 	{ "trace",	cmd_trace,	0 },
63 #endif
64 	{ "inject",	cmd_inject,	0 },
65 	{ "mem",	cmd_mem,	0 },
66 	{ "data",	cmd_data,	0 },
67 };
68 
69 struct pager_config {
70 	const char *cmd;
71 	int val;
72 };
73 
74 static int pager_command_config(const char *var, const char *value, void *data)
75 {
76 	struct pager_config *c = data;
77 	if (!prefixcmp(var, "pager.") && !strcmp(var + 6, c->cmd))
78 		c->val = perf_config_bool(var, value);
79 	return 0;
80 }
81 
82 /* returns 0 for "no pager", 1 for "use pager", and -1 for "not specified" */
83 int check_pager_config(const char *cmd)
84 {
85 	struct pager_config c;
86 	c.cmd = cmd;
87 	c.val = -1;
88 	perf_config(pager_command_config, &c);
89 	return c.val;
90 }
91 
92 static int browser_command_config(const char *var, const char *value, void *data)
93 {
94 	struct pager_config *c = data;
95 	if (!prefixcmp(var, "tui.") && !strcmp(var + 4, c->cmd))
96 		c->val = perf_config_bool(var, value);
97 	if (!prefixcmp(var, "gtk.") && !strcmp(var + 4, c->cmd))
98 		c->val = perf_config_bool(var, value) ? 2 : 0;
99 	return 0;
100 }
101 
102 /*
103  * returns 0 for "no tui", 1 for "use tui", 2 for "use gtk",
104  * and -1 for "not specified"
105  */
106 static int check_browser_config(const char *cmd)
107 {
108 	struct pager_config c;
109 	c.cmd = cmd;
110 	c.val = -1;
111 	perf_config(browser_command_config, &c);
112 	return c.val;
113 }
114 
115 static void commit_pager_choice(void)
116 {
117 	switch (use_pager) {
118 	case 0:
119 		setenv("PERF_PAGER", "cat", 1);
120 		break;
121 	case 1:
122 		/* setup_pager(); */
123 		break;
124 	default:
125 		break;
126 	}
127 }
128 
129 struct option options[] = {
130 	OPT_ARGUMENT("help", "help"),
131 	OPT_ARGUMENT("version", "version"),
132 	OPT_ARGUMENT("exec-path", "exec-path"),
133 	OPT_ARGUMENT("html-path", "html-path"),
134 	OPT_ARGUMENT("paginate", "paginate"),
135 	OPT_ARGUMENT("no-pager", "no-pager"),
136 	OPT_ARGUMENT("perf-dir", "perf-dir"),
137 	OPT_ARGUMENT("work-tree", "work-tree"),
138 	OPT_ARGUMENT("debugfs-dir", "debugfs-dir"),
139 	OPT_ARGUMENT("buildid-dir", "buildid-dir"),
140 	OPT_ARGUMENT("list-cmds", "list-cmds"),
141 	OPT_ARGUMENT("list-opts", "list-opts"),
142 	OPT_ARGUMENT("debug", "debug"),
143 	OPT_END()
144 };
145 
146 static int handle_options(const char ***argv, int *argc, int *envchanged)
147 {
148 	int handled = 0;
149 
150 	while (*argc > 0) {
151 		const char *cmd = (*argv)[0];
152 		if (cmd[0] != '-')
153 			break;
154 
155 		/*
156 		 * For legacy reasons, the "version" and "help"
157 		 * commands can be written with "--" prepended
158 		 * to make them look like flags.
159 		 */
160 		if (!strcmp(cmd, "--help") || !strcmp(cmd, "--version"))
161 			break;
162 
163 		/*
164 		 * Check remaining flags.
165 		 */
166 		if (!prefixcmp(cmd, CMD_EXEC_PATH)) {
167 			cmd += strlen(CMD_EXEC_PATH);
168 			if (*cmd == '=')
169 				perf_set_argv_exec_path(cmd + 1);
170 			else {
171 				puts(perf_exec_path());
172 				exit(0);
173 			}
174 		} else if (!strcmp(cmd, "--html-path")) {
175 			puts(system_path(PERF_HTML_PATH));
176 			exit(0);
177 		} else if (!strcmp(cmd, "-p") || !strcmp(cmd, "--paginate")) {
178 			use_pager = 1;
179 		} else if (!strcmp(cmd, "--no-pager")) {
180 			use_pager = 0;
181 			if (envchanged)
182 				*envchanged = 1;
183 		} else if (!strcmp(cmd, "--perf-dir")) {
184 			if (*argc < 2) {
185 				fprintf(stderr, "No directory given for --perf-dir.\n");
186 				usage(perf_usage_string);
187 			}
188 			setenv(PERF_DIR_ENVIRONMENT, (*argv)[1], 1);
189 			if (envchanged)
190 				*envchanged = 1;
191 			(*argv)++;
192 			(*argc)--;
193 			handled++;
194 		} else if (!prefixcmp(cmd, CMD_PERF_DIR)) {
195 			setenv(PERF_DIR_ENVIRONMENT, cmd + strlen(CMD_PERF_DIR), 1);
196 			if (envchanged)
197 				*envchanged = 1;
198 		} else if (!strcmp(cmd, "--work-tree")) {
199 			if (*argc < 2) {
200 				fprintf(stderr, "No directory given for --work-tree.\n");
201 				usage(perf_usage_string);
202 			}
203 			setenv(PERF_WORK_TREE_ENVIRONMENT, (*argv)[1], 1);
204 			if (envchanged)
205 				*envchanged = 1;
206 			(*argv)++;
207 			(*argc)--;
208 		} else if (!prefixcmp(cmd, CMD_WORK_TREE)) {
209 			setenv(PERF_WORK_TREE_ENVIRONMENT, cmd + strlen(CMD_WORK_TREE), 1);
210 			if (envchanged)
211 				*envchanged = 1;
212 		} else if (!strcmp(cmd, "--debugfs-dir")) {
213 			if (*argc < 2) {
214 				fprintf(stderr, "No directory given for --debugfs-dir.\n");
215 				usage(perf_usage_string);
216 			}
217 			perf_debugfs_set_path((*argv)[1]);
218 			if (envchanged)
219 				*envchanged = 1;
220 			(*argv)++;
221 			(*argc)--;
222 		} else if (!strcmp(cmd, "--buildid-dir")) {
223 			if (*argc < 2) {
224 				fprintf(stderr, "No directory given for --buildid-dir.\n");
225 				usage(perf_usage_string);
226 			}
227 			set_buildid_dir((*argv)[1]);
228 			if (envchanged)
229 				*envchanged = 1;
230 			(*argv)++;
231 			(*argc)--;
232 		} else if (!prefixcmp(cmd, CMD_DEBUGFS_DIR)) {
233 			perf_debugfs_set_path(cmd + strlen(CMD_DEBUGFS_DIR));
234 			fprintf(stderr, "dir: %s\n", tracing_path);
235 			if (envchanged)
236 				*envchanged = 1;
237 		} else if (!strcmp(cmd, "--list-cmds")) {
238 			unsigned int i;
239 
240 			for (i = 0; i < ARRAY_SIZE(commands); i++) {
241 				struct cmd_struct *p = commands+i;
242 				printf("%s ", p->cmd);
243 			}
244 			putchar('\n');
245 			exit(0);
246 		} else if (!strcmp(cmd, "--list-opts")) {
247 			unsigned int i;
248 
249 			for (i = 0; i < ARRAY_SIZE(options)-1; i++) {
250 				struct option *p = options+i;
251 				printf("--%s ", p->long_name);
252 			}
253 			putchar('\n');
254 			exit(0);
255 		} else if (!strcmp(cmd, "--debug")) {
256 			if (*argc < 2) {
257 				fprintf(stderr, "No variable specified for --debug.\n");
258 				usage(perf_usage_string);
259 			}
260 			if (perf_debug_option((*argv)[1]))
261 				usage(perf_usage_string);
262 
263 			(*argv)++;
264 			(*argc)--;
265 		} else {
266 			fprintf(stderr, "Unknown option: %s\n", cmd);
267 			usage(perf_usage_string);
268 		}
269 
270 		(*argv)++;
271 		(*argc)--;
272 		handled++;
273 	}
274 	return handled;
275 }
276 
277 static int handle_alias(int *argcp, const char ***argv)
278 {
279 	int envchanged = 0, ret = 0, saved_errno = errno;
280 	int count, option_count;
281 	const char **new_argv;
282 	const char *alias_command;
283 	char *alias_string;
284 
285 	alias_command = (*argv)[0];
286 	alias_string = alias_lookup(alias_command);
287 	if (alias_string) {
288 		if (alias_string[0] == '!') {
289 			if (*argcp > 1) {
290 				struct strbuf buf;
291 
292 				strbuf_init(&buf, PATH_MAX);
293 				strbuf_addstr(&buf, alias_string);
294 				sq_quote_argv(&buf, (*argv) + 1, PATH_MAX);
295 				free(alias_string);
296 				alias_string = buf.buf;
297 			}
298 			ret = system(alias_string + 1);
299 			if (ret >= 0 && WIFEXITED(ret) &&
300 			    WEXITSTATUS(ret) != 127)
301 				exit(WEXITSTATUS(ret));
302 			die("Failed to run '%s' when expanding alias '%s'",
303 			    alias_string + 1, alias_command);
304 		}
305 		count = split_cmdline(alias_string, &new_argv);
306 		if (count < 0)
307 			die("Bad alias.%s string", alias_command);
308 		option_count = handle_options(&new_argv, &count, &envchanged);
309 		if (envchanged)
310 			die("alias '%s' changes environment variables\n"
311 				 "You can use '!perf' in the alias to do this.",
312 				 alias_command);
313 		memmove(new_argv - option_count, new_argv,
314 				count * sizeof(char *));
315 		new_argv -= option_count;
316 
317 		if (count < 1)
318 			die("empty alias for %s", alias_command);
319 
320 		if (!strcmp(alias_command, new_argv[0]))
321 			die("recursive alias: %s", alias_command);
322 
323 		new_argv = realloc(new_argv, sizeof(char *) *
324 				    (count + *argcp + 1));
325 		/* insert after command name */
326 		memcpy(new_argv + count, *argv + 1, sizeof(char *) * *argcp);
327 		new_argv[count + *argcp] = NULL;
328 
329 		*argv = new_argv;
330 		*argcp += count - 1;
331 
332 		ret = 1;
333 	}
334 
335 	errno = saved_errno;
336 
337 	return ret;
338 }
339 
340 const char perf_version_string[] = PERF_VERSION;
341 
342 #define RUN_SETUP	(1<<0)
343 #define USE_PAGER	(1<<1)
344 /*
345  * require working tree to be present -- anything uses this needs
346  * RUN_SETUP for reading from the configuration file.
347  */
348 #define NEED_WORK_TREE	(1<<2)
349 
350 static int run_builtin(struct cmd_struct *p, int argc, const char **argv)
351 {
352 	int status;
353 	struct stat st;
354 	const char *prefix;
355 	char sbuf[STRERR_BUFSIZE];
356 
357 	prefix = NULL;
358 	if (p->option & RUN_SETUP)
359 		prefix = NULL; /* setup_perf_directory(); */
360 
361 	if (use_browser == -1)
362 		use_browser = check_browser_config(p->cmd);
363 
364 	if (use_pager == -1 && p->option & RUN_SETUP)
365 		use_pager = check_pager_config(p->cmd);
366 	if (use_pager == -1 && p->option & USE_PAGER)
367 		use_pager = 1;
368 	commit_pager_choice();
369 
370 	status = p->fn(argc, argv, prefix);
371 	exit_browser(status);
372 
373 	if (status)
374 		return status & 0xff;
375 
376 	/* Somebody closed stdout? */
377 	if (fstat(fileno(stdout), &st))
378 		return 0;
379 	/* Ignore write errors for pipes and sockets.. */
380 	if (S_ISFIFO(st.st_mode) || S_ISSOCK(st.st_mode))
381 		return 0;
382 
383 	status = 1;
384 	/* Check for ENOSPC and EIO errors.. */
385 	if (fflush(stdout)) {
386 		fprintf(stderr, "write failure on standard output: %s",
387 			strerror_r(errno, sbuf, sizeof(sbuf)));
388 		goto out;
389 	}
390 	if (ferror(stdout)) {
391 		fprintf(stderr, "unknown write failure on standard output");
392 		goto out;
393 	}
394 	if (fclose(stdout)) {
395 		fprintf(stderr, "close failed on standard output: %s",
396 			strerror_r(errno, sbuf, sizeof(sbuf)));
397 		goto out;
398 	}
399 	status = 0;
400 out:
401 	return status;
402 }
403 
404 static void handle_internal_command(int argc, const char **argv)
405 {
406 	const char *cmd = argv[0];
407 	unsigned int i;
408 	static const char ext[] = STRIP_EXTENSION;
409 
410 	if (sizeof(ext) > 1) {
411 		i = strlen(argv[0]) - strlen(ext);
412 		if (i > 0 && !strcmp(argv[0] + i, ext)) {
413 			char *argv0 = strdup(argv[0]);
414 			argv[0] = cmd = argv0;
415 			argv0[i] = '\0';
416 		}
417 	}
418 
419 	/* Turn "perf cmd --help" into "perf help cmd" */
420 	if (argc > 1 && !strcmp(argv[1], "--help")) {
421 		argv[1] = argv[0];
422 		argv[0] = cmd = "help";
423 	}
424 
425 	for (i = 0; i < ARRAY_SIZE(commands); i++) {
426 		struct cmd_struct *p = commands+i;
427 		if (strcmp(p->cmd, cmd))
428 			continue;
429 		exit(run_builtin(p, argc, argv));
430 	}
431 }
432 
433 static void execv_dashed_external(const char **argv)
434 {
435 	struct strbuf cmd = STRBUF_INIT;
436 	const char *tmp;
437 	int status;
438 
439 	strbuf_addf(&cmd, "perf-%s", argv[0]);
440 
441 	/*
442 	 * argv[0] must be the perf command, but the argv array
443 	 * belongs to the caller, and may be reused in
444 	 * subsequent loop iterations. Save argv[0] and
445 	 * restore it on error.
446 	 */
447 	tmp = argv[0];
448 	argv[0] = cmd.buf;
449 
450 	/*
451 	 * if we fail because the command is not found, it is
452 	 * OK to return. Otherwise, we just pass along the status code.
453 	 */
454 	status = run_command_v_opt(argv, 0);
455 	if (status != -ERR_RUN_COMMAND_EXEC) {
456 		if (IS_RUN_COMMAND_ERR(status))
457 			die("unable to run '%s'", argv[0]);
458 		exit(-status);
459 	}
460 	errno = ENOENT; /* as if we called execvp */
461 
462 	argv[0] = tmp;
463 
464 	strbuf_release(&cmd);
465 }
466 
467 static int run_argv(int *argcp, const char ***argv)
468 {
469 	int done_alias = 0;
470 
471 	while (1) {
472 		/* See if it's an internal command */
473 		handle_internal_command(*argcp, *argv);
474 
475 		/* .. then try the external ones */
476 		execv_dashed_external(*argv);
477 
478 		/* It could be an alias -- this works around the insanity
479 		 * of overriding "perf log" with "perf show" by having
480 		 * alias.log = show
481 		 */
482 		if (done_alias || !handle_alias(argcp, argv))
483 			break;
484 		done_alias = 1;
485 	}
486 
487 	return done_alias;
488 }
489 
490 static void pthread__block_sigwinch(void)
491 {
492 	sigset_t set;
493 
494 	sigemptyset(&set);
495 	sigaddset(&set, SIGWINCH);
496 	pthread_sigmask(SIG_BLOCK, &set, NULL);
497 }
498 
499 void pthread__unblock_sigwinch(void)
500 {
501 	sigset_t set;
502 
503 	sigemptyset(&set);
504 	sigaddset(&set, SIGWINCH);
505 	pthread_sigmask(SIG_UNBLOCK, &set, NULL);
506 }
507 
508 int main(int argc, const char **argv)
509 {
510 	const char *cmd;
511 	char sbuf[STRERR_BUFSIZE];
512 
513 	/* The page_size is placed in util object. */
514 	page_size = sysconf(_SC_PAGE_SIZE);
515 	cacheline_size = sysconf(_SC_LEVEL1_DCACHE_LINESIZE);
516 
517 	cmd = perf_extract_argv0_path(argv[0]);
518 	if (!cmd)
519 		cmd = "perf-help";
520 	/* get debugfs mount point from /proc/mounts */
521 	perf_debugfs_mount(NULL);
522 	/*
523 	 * "perf-xxxx" is the same as "perf xxxx", but we obviously:
524 	 *
525 	 *  - cannot take flags in between the "perf" and the "xxxx".
526 	 *  - cannot execute it externally (since it would just do
527 	 *    the same thing over again)
528 	 *
529 	 * So we just directly call the internal command handler, and
530 	 * die if that one cannot handle it.
531 	 */
532 	if (!prefixcmp(cmd, "perf-")) {
533 		cmd += 5;
534 		argv[0] = cmd;
535 		handle_internal_command(argc, argv);
536 		fprintf(stderr, "cannot handle %s internally", cmd);
537 		goto out;
538 	}
539 	if (!prefixcmp(cmd, "trace")) {
540 #ifdef HAVE_LIBAUDIT_SUPPORT
541 		set_buildid_dir(NULL);
542 		setup_path();
543 		argv[0] = "trace";
544 		return cmd_trace(argc, argv, NULL);
545 #else
546 		fprintf(stderr,
547 			"trace command not available: missing audit-libs devel package at build time.\n");
548 		goto out;
549 #endif
550 	}
551 	/* Look for flags.. */
552 	argv++;
553 	argc--;
554 	handle_options(&argv, &argc, NULL);
555 	commit_pager_choice();
556 	set_buildid_dir(NULL);
557 
558 	if (argc > 0) {
559 		if (!prefixcmp(argv[0], "--"))
560 			argv[0] += 2;
561 	} else {
562 		/* The user didn't specify a command; give them help */
563 		printf("\n usage: %s\n\n", perf_usage_string);
564 		list_common_cmds_help();
565 		printf("\n %s\n\n", perf_more_info_string);
566 		goto out;
567 	}
568 	cmd = argv[0];
569 
570 	test_attr__init();
571 
572 	/*
573 	 * We use PATH to find perf commands, but we prepend some higher
574 	 * precedence paths: the "--exec-path" option, the PERF_EXEC_PATH
575 	 * environment, and the $(perfexecdir) from the Makefile at build
576 	 * time.
577 	 */
578 	setup_path();
579 	/*
580 	 * Block SIGWINCH notifications so that the thread that wants it can
581 	 * unblock and get syscalls like select interrupted instead of waiting
582 	 * forever while the signal goes to some other non interested thread.
583 	 */
584 	pthread__block_sigwinch();
585 
586 	while (1) {
587 		static int done_help;
588 		int was_alias = run_argv(&argc, &argv);
589 
590 		if (errno != ENOENT)
591 			break;
592 
593 		if (was_alias) {
594 			fprintf(stderr, "Expansion of alias '%s' failed; "
595 				"'%s' is not a perf-command\n",
596 				cmd, argv[0]);
597 			goto out;
598 		}
599 		if (!done_help) {
600 			cmd = argv[0] = help_unknown_cmd(cmd);
601 			done_help = 1;
602 		} else
603 			break;
604 	}
605 
606 	fprintf(stderr, "Failed to run command '%s': %s\n",
607 		cmd, strerror_r(errno, sbuf, sizeof(sbuf)));
608 out:
609 	return 1;
610 }
611