xref: /openbmc/linux/tools/perf/perf.c (revision a8da474e) 
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 "util/exec_cmd.h"
13 #include "util/cache.h"
14 #include "util/quote.h"
15 #include "util/run-command.h"
16 #include "util/parse-events.h"
17 #include "util/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 	{ "diff",	cmd_diff,	0 },
43 	{ "evlist",	cmd_evlist,	0 },
44 	{ "help",	cmd_help,	0 },
45 	{ "list",	cmd_list,	0 },
46 	{ "record",	cmd_record,	0 },
47 	{ "report",	cmd_report,	0 },
48 	{ "bench",	cmd_bench,	0 },
49 	{ "stat",	cmd_stat,	0 },
50 	{ "timechart",	cmd_timechart,	0 },
51 	{ "top",	cmd_top,	0 },
52 	{ "annotate",	cmd_annotate,	0 },
53 	{ "version",	cmd_version,	0 },
54 	{ "script",	cmd_script,	0 },
55 	{ "sched",	cmd_sched,	0 },
56 #ifdef HAVE_LIBELF_SUPPORT
57 	{ "probe",	cmd_probe,	0 },
58 #endif
59 	{ "kmem",	cmd_kmem,	0 },
60 	{ "lock",	cmd_lock,	0 },
61 	{ "kvm",	cmd_kvm,	0 },
62 	{ "test",	cmd_test,	0 },
63 #ifdef HAVE_LIBAUDIT_SUPPORT
64 	{ "trace",	cmd_trace,	0 },
65 #endif
66 	{ "inject",	cmd_inject,	0 },
67 	{ "mem",	cmd_mem,	0 },
68 	{ "data",	cmd_data,	0 },
69 };
70 
71 struct pager_config {
72 	const char *cmd;
73 	int val;
74 };
75 
76 static int pager_command_config(const char *var, const char *value, void *data)
77 {
78 	struct pager_config *c = data;
79 	if (!prefixcmp(var, "pager.") && !strcmp(var + 6, c->cmd))
80 		c->val = perf_config_bool(var, value);
81 	return 0;
82 }
83 
84 /* returns 0 for "no pager", 1 for "use pager", and -1 for "not specified" */
85 int check_pager_config(const char *cmd)
86 {
87 	struct pager_config c;
88 	c.cmd = cmd;
89 	c.val = -1;
90 	perf_config(pager_command_config, &c);
91 	return c.val;
92 }
93 
94 static int browser_command_config(const char *var, const char *value, void *data)
95 {
96 	struct pager_config *c = data;
97 	if (!prefixcmp(var, "tui.") && !strcmp(var + 4, c->cmd))
98 		c->val = perf_config_bool(var, value);
99 	if (!prefixcmp(var, "gtk.") && !strcmp(var + 4, c->cmd))
100 		c->val = perf_config_bool(var, value) ? 2 : 0;
101 	return 0;
102 }
103 
104 /*
105  * returns 0 for "no tui", 1 for "use tui", 2 for "use gtk",
106  * and -1 for "not specified"
107  */
108 static int check_browser_config(const char *cmd)
109 {
110 	struct pager_config c;
111 	c.cmd = cmd;
112 	c.val = -1;
113 	perf_config(browser_command_config, &c);
114 	return c.val;
115 }
116 
117 static void commit_pager_choice(void)
118 {
119 	switch (use_pager) {
120 	case 0:
121 		setenv("PERF_PAGER", "cat", 1);
122 		break;
123 	case 1:
124 		/* setup_pager(); */
125 		break;
126 	default:
127 		break;
128 	}
129 }
130 
131 struct option options[] = {
132 	OPT_ARGUMENT("help", "help"),
133 	OPT_ARGUMENT("version", "version"),
134 	OPT_ARGUMENT("exec-path", "exec-path"),
135 	OPT_ARGUMENT("html-path", "html-path"),
136 	OPT_ARGUMENT("paginate", "paginate"),
137 	OPT_ARGUMENT("no-pager", "no-pager"),
138 	OPT_ARGUMENT("perf-dir", "perf-dir"),
139 	OPT_ARGUMENT("work-tree", "work-tree"),
140 	OPT_ARGUMENT("debugfs-dir", "debugfs-dir"),
141 	OPT_ARGUMENT("buildid-dir", "buildid-dir"),
142 	OPT_ARGUMENT("list-cmds", "list-cmds"),
143 	OPT_ARGUMENT("list-opts", "list-opts"),
144 	OPT_ARGUMENT("debug", "debug"),
145 	OPT_END()
146 };
147 
148 static int handle_options(const char ***argv, int *argc, int *envchanged)
149 {
150 	int handled = 0;
151 
152 	while (*argc > 0) {
153 		const char *cmd = (*argv)[0];
154 		if (cmd[0] != '-')
155 			break;
156 
157 		/*
158 		 * For legacy reasons, the "version" and "help"
159 		 * commands can be written with "--" prepended
160 		 * to make them look like flags.
161 		 */
162 		if (!strcmp(cmd, "--help") || !strcmp(cmd, "--version"))
163 			break;
164 
165 		/*
166 		 * Shortcut for '-h' and '-v' options to invoke help
167 		 * and version command.
168 		 */
169 		if (!strcmp(cmd, "-h")) {
170 			(*argv)[0] = "--help";
171 			break;
172 		}
173 
174 		if (!strcmp(cmd, "-v")) {
175 			(*argv)[0] = "--version";
176 			break;
177 		}
178 
179 		/*
180 		 * Check remaining flags.
181 		 */
182 		if (!prefixcmp(cmd, CMD_EXEC_PATH)) {
183 			cmd += strlen(CMD_EXEC_PATH);
184 			if (*cmd == '=')
185 				perf_set_argv_exec_path(cmd + 1);
186 			else {
187 				puts(perf_exec_path());
188 				exit(0);
189 			}
190 		} else if (!strcmp(cmd, "--html-path")) {
191 			puts(system_path(PERF_HTML_PATH));
192 			exit(0);
193 		} else if (!strcmp(cmd, "-p") || !strcmp(cmd, "--paginate")) {
194 			use_pager = 1;
195 		} else if (!strcmp(cmd, "--no-pager")) {
196 			use_pager = 0;
197 			if (envchanged)
198 				*envchanged = 1;
199 		} else if (!strcmp(cmd, "--perf-dir")) {
200 			if (*argc < 2) {
201 				fprintf(stderr, "No directory given for --perf-dir.\n");
202 				usage(perf_usage_string);
203 			}
204 			setenv(PERF_DIR_ENVIRONMENT, (*argv)[1], 1);
205 			if (envchanged)
206 				*envchanged = 1;
207 			(*argv)++;
208 			(*argc)--;
209 			handled++;
210 		} else if (!prefixcmp(cmd, CMD_PERF_DIR)) {
211 			setenv(PERF_DIR_ENVIRONMENT, cmd + strlen(CMD_PERF_DIR), 1);
212 			if (envchanged)
213 				*envchanged = 1;
214 		} else if (!strcmp(cmd, "--work-tree")) {
215 			if (*argc < 2) {
216 				fprintf(stderr, "No directory given for --work-tree.\n");
217 				usage(perf_usage_string);
218 			}
219 			setenv(PERF_WORK_TREE_ENVIRONMENT, (*argv)[1], 1);
220 			if (envchanged)
221 				*envchanged = 1;
222 			(*argv)++;
223 			(*argc)--;
224 		} else if (!prefixcmp(cmd, CMD_WORK_TREE)) {
225 			setenv(PERF_WORK_TREE_ENVIRONMENT, cmd + strlen(CMD_WORK_TREE), 1);
226 			if (envchanged)
227 				*envchanged = 1;
228 		} else if (!strcmp(cmd, "--debugfs-dir")) {
229 			if (*argc < 2) {
230 				fprintf(stderr, "No directory given for --debugfs-dir.\n");
231 				usage(perf_usage_string);
232 			}
233 			tracing_path_set((*argv)[1]);
234 			if (envchanged)
235 				*envchanged = 1;
236 			(*argv)++;
237 			(*argc)--;
238 		} else if (!strcmp(cmd, "--buildid-dir")) {
239 			if (*argc < 2) {
240 				fprintf(stderr, "No directory given for --buildid-dir.\n");
241 				usage(perf_usage_string);
242 			}
243 			set_buildid_dir((*argv)[1]);
244 			if (envchanged)
245 				*envchanged = 1;
246 			(*argv)++;
247 			(*argc)--;
248 		} else if (!prefixcmp(cmd, CMD_DEBUGFS_DIR)) {
249 			tracing_path_set(cmd + strlen(CMD_DEBUGFS_DIR));
250 			fprintf(stderr, "dir: %s\n", tracing_path);
251 			if (envchanged)
252 				*envchanged = 1;
253 		} else if (!strcmp(cmd, "--list-cmds")) {
254 			unsigned int i;
255 
256 			for (i = 0; i < ARRAY_SIZE(commands); i++) {
257 				struct cmd_struct *p = commands+i;
258 				printf("%s ", p->cmd);
259 			}
260 			putchar('\n');
261 			exit(0);
262 		} else if (!strcmp(cmd, "--list-opts")) {
263 			unsigned int i;
264 
265 			for (i = 0; i < ARRAY_SIZE(options)-1; i++) {
266 				struct option *p = options+i;
267 				printf("--%s ", p->long_name);
268 			}
269 			putchar('\n');
270 			exit(0);
271 		} else if (!strcmp(cmd, "--debug")) {
272 			if (*argc < 2) {
273 				fprintf(stderr, "No variable specified for --debug.\n");
274 				usage(perf_usage_string);
275 			}
276 			if (perf_debug_option((*argv)[1]))
277 				usage(perf_usage_string);
278 
279 			(*argv)++;
280 			(*argc)--;
281 		} else {
282 			fprintf(stderr, "Unknown option: %s\n", cmd);
283 			usage(perf_usage_string);
284 		}
285 
286 		(*argv)++;
287 		(*argc)--;
288 		handled++;
289 	}
290 	return handled;
291 }
292 
293 static int handle_alias(int *argcp, const char ***argv)
294 {
295 	int envchanged = 0, ret = 0, saved_errno = errno;
296 	int count, option_count;
297 	const char **new_argv;
298 	const char *alias_command;
299 	char *alias_string;
300 
301 	alias_command = (*argv)[0];
302 	alias_string = alias_lookup(alias_command);
303 	if (alias_string) {
304 		if (alias_string[0] == '!') {
305 			if (*argcp > 1) {
306 				struct strbuf buf;
307 
308 				strbuf_init(&buf, PATH_MAX);
309 				strbuf_addstr(&buf, alias_string);
310 				sq_quote_argv(&buf, (*argv) + 1, PATH_MAX);
311 				free(alias_string);
312 				alias_string = buf.buf;
313 			}
314 			ret = system(alias_string + 1);
315 			if (ret >= 0 && WIFEXITED(ret) &&
316 			    WEXITSTATUS(ret) != 127)
317 				exit(WEXITSTATUS(ret));
318 			die("Failed to run '%s' when expanding alias '%s'",
319 			    alias_string + 1, alias_command);
320 		}
321 		count = split_cmdline(alias_string, &new_argv);
322 		if (count < 0)
323 			die("Bad alias.%s string", alias_command);
324 		option_count = handle_options(&new_argv, &count, &envchanged);
325 		if (envchanged)
326 			die("alias '%s' changes environment variables\n"
327 				 "You can use '!perf' in the alias to do this.",
328 				 alias_command);
329 		memmove(new_argv - option_count, new_argv,
330 				count * sizeof(char *));
331 		new_argv -= option_count;
332 
333 		if (count < 1)
334 			die("empty alias for %s", alias_command);
335 
336 		if (!strcmp(alias_command, new_argv[0]))
337 			die("recursive alias: %s", alias_command);
338 
339 		new_argv = realloc(new_argv, sizeof(char *) *
340 				    (count + *argcp + 1));
341 		/* insert after command name */
342 		memcpy(new_argv + count, *argv + 1, sizeof(char *) * *argcp);
343 		new_argv[count + *argcp] = NULL;
344 
345 		*argv = new_argv;
346 		*argcp += count - 1;
347 
348 		ret = 1;
349 	}
350 
351 	errno = saved_errno;
352 
353 	return ret;
354 }
355 
356 const char perf_version_string[] = PERF_VERSION;
357 
358 #define RUN_SETUP	(1<<0)
359 #define USE_PAGER	(1<<1)
360 /*
361  * require working tree to be present -- anything uses this needs
362  * RUN_SETUP for reading from the configuration file.
363  */
364 #define NEED_WORK_TREE	(1<<2)
365 
366 static int run_builtin(struct cmd_struct *p, int argc, const char **argv)
367 {
368 	int status;
369 	struct stat st;
370 	const char *prefix;
371 	char sbuf[STRERR_BUFSIZE];
372 
373 	prefix = NULL;
374 	if (p->option & RUN_SETUP)
375 		prefix = NULL; /* setup_perf_directory(); */
376 
377 	if (use_browser == -1)
378 		use_browser = check_browser_config(p->cmd);
379 
380 	if (use_pager == -1 && p->option & RUN_SETUP)
381 		use_pager = check_pager_config(p->cmd);
382 	if (use_pager == -1 && p->option & USE_PAGER)
383 		use_pager = 1;
384 	commit_pager_choice();
385 
386 	status = p->fn(argc, argv, prefix);
387 	exit_browser(status);
388 	perf_env__exit(&perf_env);
389 	bpf__clear();
390 
391 	if (status)
392 		return status & 0xff;
393 
394 	/* Somebody closed stdout? */
395 	if (fstat(fileno(stdout), &st))
396 		return 0;
397 	/* Ignore write errors for pipes and sockets.. */
398 	if (S_ISFIFO(st.st_mode) || S_ISSOCK(st.st_mode))
399 		return 0;
400 
401 	status = 1;
402 	/* Check for ENOSPC and EIO errors.. */
403 	if (fflush(stdout)) {
404 		fprintf(stderr, "write failure on standard output: %s",
405 			strerror_r(errno, sbuf, sizeof(sbuf)));
406 		goto out;
407 	}
408 	if (ferror(stdout)) {
409 		fprintf(stderr, "unknown write failure on standard output");
410 		goto out;
411 	}
412 	if (fclose(stdout)) {
413 		fprintf(stderr, "close failed on standard output: %s",
414 			strerror_r(errno, sbuf, sizeof(sbuf)));
415 		goto out;
416 	}
417 	status = 0;
418 out:
419 	return status;
420 }
421 
422 static void handle_internal_command(int argc, const char **argv)
423 {
424 	const char *cmd = argv[0];
425 	unsigned int i;
426 	static const char ext[] = STRIP_EXTENSION;
427 
428 	if (sizeof(ext) > 1) {
429 		i = strlen(argv[0]) - strlen(ext);
430 		if (i > 0 && !strcmp(argv[0] + i, ext)) {
431 			char *argv0 = strdup(argv[0]);
432 			argv[0] = cmd = argv0;
433 			argv0[i] = '\0';
434 		}
435 	}
436 
437 	/* Turn "perf cmd --help" into "perf help cmd" */
438 	if (argc > 1 && !strcmp(argv[1], "--help")) {
439 		argv[1] = argv[0];
440 		argv[0] = cmd = "help";
441 	}
442 
443 	for (i = 0; i < ARRAY_SIZE(commands); i++) {
444 		struct cmd_struct *p = commands+i;
445 		if (strcmp(p->cmd, cmd))
446 			continue;
447 		exit(run_builtin(p, argc, argv));
448 	}
449 }
450 
451 static void execv_dashed_external(const char **argv)
452 {
453 	struct strbuf cmd = STRBUF_INIT;
454 	const char *tmp;
455 	int status;
456 
457 	strbuf_addf(&cmd, "perf-%s", argv[0]);
458 
459 	/*
460 	 * argv[0] must be the perf command, but the argv array
461 	 * belongs to the caller, and may be reused in
462 	 * subsequent loop iterations. Save argv[0] and
463 	 * restore it on error.
464 	 */
465 	tmp = argv[0];
466 	argv[0] = cmd.buf;
467 
468 	/*
469 	 * if we fail because the command is not found, it is
470 	 * OK to return. Otherwise, we just pass along the status code.
471 	 */
472 	status = run_command_v_opt(argv, 0);
473 	if (status != -ERR_RUN_COMMAND_EXEC) {
474 		if (IS_RUN_COMMAND_ERR(status))
475 			die("unable to run '%s'", argv[0]);
476 		exit(-status);
477 	}
478 	errno = ENOENT; /* as if we called execvp */
479 
480 	argv[0] = tmp;
481 
482 	strbuf_release(&cmd);
483 }
484 
485 static int run_argv(int *argcp, const char ***argv)
486 {
487 	int done_alias = 0;
488 
489 	while (1) {
490 		/* See if it's an internal command */
491 		handle_internal_command(*argcp, *argv);
492 
493 		/* .. then try the external ones */
494 		execv_dashed_external(*argv);
495 
496 		/* It could be an alias -- this works around the insanity
497 		 * of overriding "perf log" with "perf show" by having
498 		 * alias.log = show
499 		 */
500 		if (done_alias || !handle_alias(argcp, argv))
501 			break;
502 		done_alias = 1;
503 	}
504 
505 	return done_alias;
506 }
507 
508 static void pthread__block_sigwinch(void)
509 {
510 	sigset_t set;
511 
512 	sigemptyset(&set);
513 	sigaddset(&set, SIGWINCH);
514 	pthread_sigmask(SIG_BLOCK, &set, NULL);
515 }
516 
517 void pthread__unblock_sigwinch(void)
518 {
519 	sigset_t set;
520 
521 	sigemptyset(&set);
522 	sigaddset(&set, SIGWINCH);
523 	pthread_sigmask(SIG_UNBLOCK, &set, NULL);
524 }
525 
526 int main(int argc, const char **argv)
527 {
528 	const char *cmd;
529 	char sbuf[STRERR_BUFSIZE];
530 
531 	/* The page_size is placed in util object. */
532 	page_size = sysconf(_SC_PAGE_SIZE);
533 	cacheline_size = sysconf(_SC_LEVEL1_DCACHE_LINESIZE);
534 
535 	cmd = perf_extract_argv0_path(argv[0]);
536 	if (!cmd)
537 		cmd = "perf-help";
538 
539 	/* get debugfs/tracefs mount point from /proc/mounts */
540 	tracing_path_mount();
541 
542 	/*
543 	 * "perf-xxxx" is the same as "perf xxxx", but we obviously:
544 	 *
545 	 *  - cannot take flags in between the "perf" and the "xxxx".
546 	 *  - cannot execute it externally (since it would just do
547 	 *    the same thing over again)
548 	 *
549 	 * So we just directly call the internal command handler, and
550 	 * die if that one cannot handle it.
551 	 */
552 	if (!prefixcmp(cmd, "perf-")) {
553 		cmd += 5;
554 		argv[0] = cmd;
555 		handle_internal_command(argc, argv);
556 		fprintf(stderr, "cannot handle %s internally", cmd);
557 		goto out;
558 	}
559 	if (!prefixcmp(cmd, "trace")) {
560 #ifdef HAVE_LIBAUDIT_SUPPORT
561 		set_buildid_dir(NULL);
562 		setup_path();
563 		argv[0] = "trace";
564 		return cmd_trace(argc, argv, NULL);
565 #else
566 		fprintf(stderr,
567 			"trace command not available: missing audit-libs devel package at build time.\n");
568 		goto out;
569 #endif
570 	}
571 	/* Look for flags.. */
572 	argv++;
573 	argc--;
574 	handle_options(&argv, &argc, NULL);
575 	commit_pager_choice();
576 	set_buildid_dir(NULL);
577 
578 	if (argc > 0) {
579 		if (!prefixcmp(argv[0], "--"))
580 			argv[0] += 2;
581 	} else {
582 		/* The user didn't specify a command; give them help */
583 		printf("\n usage: %s\n\n", perf_usage_string);
584 		list_common_cmds_help();
585 		printf("\n %s\n\n", perf_more_info_string);
586 		goto out;
587 	}
588 	cmd = argv[0];
589 
590 	test_attr__init();
591 
592 	/*
593 	 * We use PATH to find perf commands, but we prepend some higher
594 	 * precedence paths: the "--exec-path" option, the PERF_EXEC_PATH
595 	 * environment, and the $(perfexecdir) from the Makefile at build
596 	 * time.
597 	 */
598 	setup_path();
599 	/*
600 	 * Block SIGWINCH notifications so that the thread that wants it can
601 	 * unblock and get syscalls like select interrupted instead of waiting
602 	 * forever while the signal goes to some other non interested thread.
603 	 */
604 	pthread__block_sigwinch();
605 
606 	while (1) {
607 		static int done_help;
608 		int was_alias = run_argv(&argc, &argv);
609 
610 		if (errno != ENOENT)
611 			break;
612 
613 		if (was_alias) {
614 			fprintf(stderr, "Expansion of alias '%s' failed; "
615 				"'%s' is not a perf-command\n",
616 				cmd, argv[0]);
617 			goto out;
618 		}
619 		if (!done_help) {
620 			cmd = argv[0] = help_unknown_cmd(cmd);
621 			done_help = 1;
622 		} else
623 			break;
624 	}
625 
626 	fprintf(stderr, "Failed to run command '%s': %s\n",
627 		cmd, strerror_r(errno, sbuf, sizeof(sbuf)));
628 out:
629 	return 1;
630 }
631