xref: /linux/tools/perf/perf.c (revision 9e9f60108423f18a99c9cc93ef7f23490ecc709b)
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/debug.h"
17 #include <api/fs/debugfs.h>
18 #include <pthread.h>
19 
20 const char perf_usage_string[] =
21 	"perf [--version] [--help] [OPTIONS] COMMAND [ARGS]";
22 
23 const char perf_more_info_string[] =
24 	"See 'perf help COMMAND' for more information on a specific command.";
25 
26 int use_browser = -1;
27 static int use_pager = -1;
28 const char *input_name;
29 
30 struct cmd_struct {
31 	const char *cmd;
32 	int (*fn)(int, const char **, const char *);
33 	int option;
34 };
35 
36 static struct cmd_struct commands[] = {
37 	{ "buildid-cache", cmd_buildid_cache, 0 },
38 	{ "buildid-list", cmd_buildid_list, 0 },
39 	{ "diff",	cmd_diff,	0 },
40 	{ "evlist",	cmd_evlist,	0 },
41 	{ "help",	cmd_help,	0 },
42 	{ "list",	cmd_list,	0 },
43 	{ "record",	cmd_record,	0 },
44 	{ "report",	cmd_report,	0 },
45 	{ "bench",	cmd_bench,	0 },
46 	{ "stat",	cmd_stat,	0 },
47 	{ "timechart",	cmd_timechart,	0 },
48 	{ "top",	cmd_top,	0 },
49 	{ "annotate",	cmd_annotate,	0 },
50 	{ "version",	cmd_version,	0 },
51 	{ "script",	cmd_script,	0 },
52 	{ "sched",	cmd_sched,	0 },
53 #ifdef HAVE_LIBELF_SUPPORT
54 	{ "probe",	cmd_probe,	0 },
55 #endif
56 	{ "kmem",	cmd_kmem,	0 },
57 	{ "lock",	cmd_lock,	0 },
58 	{ "kvm",	cmd_kvm,	0 },
59 	{ "test",	cmd_test,	0 },
60 #ifdef HAVE_LIBAUDIT_SUPPORT
61 	{ "trace",	cmd_trace,	0 },
62 #endif
63 	{ "inject",	cmd_inject,	0 },
64 	{ "mem",	cmd_mem,	0 },
65 };
66 
67 struct pager_config {
68 	const char *cmd;
69 	int val;
70 };
71 
72 static int pager_command_config(const char *var, const char *value, void *data)
73 {
74 	struct pager_config *c = data;
75 	if (!prefixcmp(var, "pager.") && !strcmp(var + 6, c->cmd))
76 		c->val = perf_config_bool(var, value);
77 	return 0;
78 }
79 
80 /* returns 0 for "no pager", 1 for "use pager", and -1 for "not specified" */
81 int check_pager_config(const char *cmd)
82 {
83 	struct pager_config c;
84 	c.cmd = cmd;
85 	c.val = -1;
86 	perf_config(pager_command_config, &c);
87 	return c.val;
88 }
89 
90 static int browser_command_config(const char *var, const char *value, void *data)
91 {
92 	struct pager_config *c = data;
93 	if (!prefixcmp(var, "tui.") && !strcmp(var + 4, c->cmd))
94 		c->val = perf_config_bool(var, value);
95 	if (!prefixcmp(var, "gtk.") && !strcmp(var + 4, c->cmd))
96 		c->val = perf_config_bool(var, value) ? 2 : 0;
97 	return 0;
98 }
99 
100 /*
101  * returns 0 for "no tui", 1 for "use tui", 2 for "use gtk",
102  * and -1 for "not specified"
103  */
104 static int check_browser_config(const char *cmd)
105 {
106 	struct pager_config c;
107 	c.cmd = cmd;
108 	c.val = -1;
109 	perf_config(browser_command_config, &c);
110 	return c.val;
111 }
112 
113 static void commit_pager_choice(void)
114 {
115 	switch (use_pager) {
116 	case 0:
117 		setenv("PERF_PAGER", "cat", 1);
118 		break;
119 	case 1:
120 		/* setup_pager(); */
121 		break;
122 	default:
123 		break;
124 	}
125 }
126 
127 static int handle_options(const char ***argv, int *argc, int *envchanged)
128 {
129 	int handled = 0;
130 
131 	while (*argc > 0) {
132 		const char *cmd = (*argv)[0];
133 		if (cmd[0] != '-')
134 			break;
135 
136 		/*
137 		 * For legacy reasons, the "version" and "help"
138 		 * commands can be written with "--" prepended
139 		 * to make them look like flags.
140 		 */
141 		if (!strcmp(cmd, "--help") || !strcmp(cmd, "--version"))
142 			break;
143 
144 		/*
145 		 * Check remaining flags.
146 		 */
147 		if (!prefixcmp(cmd, CMD_EXEC_PATH)) {
148 			cmd += strlen(CMD_EXEC_PATH);
149 			if (*cmd == '=')
150 				perf_set_argv_exec_path(cmd + 1);
151 			else {
152 				puts(perf_exec_path());
153 				exit(0);
154 			}
155 		} else if (!strcmp(cmd, "--html-path")) {
156 			puts(system_path(PERF_HTML_PATH));
157 			exit(0);
158 		} else if (!strcmp(cmd, "-p") || !strcmp(cmd, "--paginate")) {
159 			use_pager = 1;
160 		} else if (!strcmp(cmd, "--no-pager")) {
161 			use_pager = 0;
162 			if (envchanged)
163 				*envchanged = 1;
164 		} else if (!strcmp(cmd, "--perf-dir")) {
165 			if (*argc < 2) {
166 				fprintf(stderr, "No directory given for --perf-dir.\n");
167 				usage(perf_usage_string);
168 			}
169 			setenv(PERF_DIR_ENVIRONMENT, (*argv)[1], 1);
170 			if (envchanged)
171 				*envchanged = 1;
172 			(*argv)++;
173 			(*argc)--;
174 			handled++;
175 		} else if (!prefixcmp(cmd, CMD_PERF_DIR)) {
176 			setenv(PERF_DIR_ENVIRONMENT, cmd + strlen(CMD_PERF_DIR), 1);
177 			if (envchanged)
178 				*envchanged = 1;
179 		} else if (!strcmp(cmd, "--work-tree")) {
180 			if (*argc < 2) {
181 				fprintf(stderr, "No directory given for --work-tree.\n");
182 				usage(perf_usage_string);
183 			}
184 			setenv(PERF_WORK_TREE_ENVIRONMENT, (*argv)[1], 1);
185 			if (envchanged)
186 				*envchanged = 1;
187 			(*argv)++;
188 			(*argc)--;
189 		} else if (!prefixcmp(cmd, CMD_WORK_TREE)) {
190 			setenv(PERF_WORK_TREE_ENVIRONMENT, cmd + strlen(CMD_WORK_TREE), 1);
191 			if (envchanged)
192 				*envchanged = 1;
193 		} else if (!strcmp(cmd, "--debugfs-dir")) {
194 			if (*argc < 2) {
195 				fprintf(stderr, "No directory given for --debugfs-dir.\n");
196 				usage(perf_usage_string);
197 			}
198 			perf_debugfs_set_path((*argv)[1]);
199 			if (envchanged)
200 				*envchanged = 1;
201 			(*argv)++;
202 			(*argc)--;
203 		} else if (!strcmp(cmd, "--buildid-dir")) {
204 			if (*argc < 2) {
205 				fprintf(stderr, "No directory given for --buildid-dir.\n");
206 				usage(perf_usage_string);
207 			}
208 			set_buildid_dir((*argv)[1]);
209 			if (envchanged)
210 				*envchanged = 1;
211 			(*argv)++;
212 			(*argc)--;
213 		} else if (!prefixcmp(cmd, CMD_DEBUGFS_DIR)) {
214 			perf_debugfs_set_path(cmd + strlen(CMD_DEBUGFS_DIR));
215 			fprintf(stderr, "dir: %s\n", debugfs_mountpoint);
216 			if (envchanged)
217 				*envchanged = 1;
218 		} else if (!strcmp(cmd, "--list-cmds")) {
219 			unsigned int i;
220 
221 			for (i = 0; i < ARRAY_SIZE(commands); i++) {
222 				struct cmd_struct *p = commands+i;
223 				printf("%s ", p->cmd);
224 			}
225 			exit(0);
226 		} else if (!strcmp(cmd, "--debug")) {
227 			if (*argc < 2) {
228 				fprintf(stderr, "No variable specified for --debug.\n");
229 				usage(perf_usage_string);
230 			}
231 			if (perf_debug_option((*argv)[1]))
232 				usage(perf_usage_string);
233 
234 			(*argv)++;
235 			(*argc)--;
236 		} else {
237 			fprintf(stderr, "Unknown option: %s\n", cmd);
238 			usage(perf_usage_string);
239 		}
240 
241 		(*argv)++;
242 		(*argc)--;
243 		handled++;
244 	}
245 	return handled;
246 }
247 
248 static int handle_alias(int *argcp, const char ***argv)
249 {
250 	int envchanged = 0, ret = 0, saved_errno = errno;
251 	int count, option_count;
252 	const char **new_argv;
253 	const char *alias_command;
254 	char *alias_string;
255 
256 	alias_command = (*argv)[0];
257 	alias_string = alias_lookup(alias_command);
258 	if (alias_string) {
259 		if (alias_string[0] == '!') {
260 			if (*argcp > 1) {
261 				struct strbuf buf;
262 
263 				strbuf_init(&buf, PATH_MAX);
264 				strbuf_addstr(&buf, alias_string);
265 				sq_quote_argv(&buf, (*argv) + 1, PATH_MAX);
266 				free(alias_string);
267 				alias_string = buf.buf;
268 			}
269 			ret = system(alias_string + 1);
270 			if (ret >= 0 && WIFEXITED(ret) &&
271 			    WEXITSTATUS(ret) != 127)
272 				exit(WEXITSTATUS(ret));
273 			die("Failed to run '%s' when expanding alias '%s'",
274 			    alias_string + 1, alias_command);
275 		}
276 		count = split_cmdline(alias_string, &new_argv);
277 		if (count < 0)
278 			die("Bad alias.%s string", alias_command);
279 		option_count = handle_options(&new_argv, &count, &envchanged);
280 		if (envchanged)
281 			die("alias '%s' changes environment variables\n"
282 				 "You can use '!perf' in the alias to do this.",
283 				 alias_command);
284 		memmove(new_argv - option_count, new_argv,
285 				count * sizeof(char *));
286 		new_argv -= option_count;
287 
288 		if (count < 1)
289 			die("empty alias for %s", alias_command);
290 
291 		if (!strcmp(alias_command, new_argv[0]))
292 			die("recursive alias: %s", alias_command);
293 
294 		new_argv = realloc(new_argv, sizeof(char *) *
295 				    (count + *argcp + 1));
296 		/* insert after command name */
297 		memcpy(new_argv + count, *argv + 1, sizeof(char *) * *argcp);
298 		new_argv[count + *argcp] = NULL;
299 
300 		*argv = new_argv;
301 		*argcp += count - 1;
302 
303 		ret = 1;
304 	}
305 
306 	errno = saved_errno;
307 
308 	return ret;
309 }
310 
311 const char perf_version_string[] = PERF_VERSION;
312 
313 #define RUN_SETUP	(1<<0)
314 #define USE_PAGER	(1<<1)
315 /*
316  * require working tree to be present -- anything uses this needs
317  * RUN_SETUP for reading from the configuration file.
318  */
319 #define NEED_WORK_TREE	(1<<2)
320 
321 static int run_builtin(struct cmd_struct *p, int argc, const char **argv)
322 {
323 	int status;
324 	struct stat st;
325 	const char *prefix;
326 	char sbuf[STRERR_BUFSIZE];
327 
328 	prefix = NULL;
329 	if (p->option & RUN_SETUP)
330 		prefix = NULL; /* setup_perf_directory(); */
331 
332 	if (use_browser == -1)
333 		use_browser = check_browser_config(p->cmd);
334 
335 	if (use_pager == -1 && p->option & RUN_SETUP)
336 		use_pager = check_pager_config(p->cmd);
337 	if (use_pager == -1 && p->option & USE_PAGER)
338 		use_pager = 1;
339 	commit_pager_choice();
340 
341 	status = p->fn(argc, argv, prefix);
342 	exit_browser(status);
343 
344 	if (status)
345 		return status & 0xff;
346 
347 	/* Somebody closed stdout? */
348 	if (fstat(fileno(stdout), &st))
349 		return 0;
350 	/* Ignore write errors for pipes and sockets.. */
351 	if (S_ISFIFO(st.st_mode) || S_ISSOCK(st.st_mode))
352 		return 0;
353 
354 	status = 1;
355 	/* Check for ENOSPC and EIO errors.. */
356 	if (fflush(stdout)) {
357 		fprintf(stderr, "write failure on standard output: %s",
358 			strerror_r(errno, sbuf, sizeof(sbuf)));
359 		goto out;
360 	}
361 	if (ferror(stdout)) {
362 		fprintf(stderr, "unknown write failure on standard output");
363 		goto out;
364 	}
365 	if (fclose(stdout)) {
366 		fprintf(stderr, "close failed on standard output: %s",
367 			strerror_r(errno, sbuf, sizeof(sbuf)));
368 		goto out;
369 	}
370 	status = 0;
371 out:
372 	return status;
373 }
374 
375 static void handle_internal_command(int argc, const char **argv)
376 {
377 	const char *cmd = argv[0];
378 	unsigned int i;
379 	static const char ext[] = STRIP_EXTENSION;
380 
381 	if (sizeof(ext) > 1) {
382 		i = strlen(argv[0]) - strlen(ext);
383 		if (i > 0 && !strcmp(argv[0] + i, ext)) {
384 			char *argv0 = strdup(argv[0]);
385 			argv[0] = cmd = argv0;
386 			argv0[i] = '\0';
387 		}
388 	}
389 
390 	/* Turn "perf cmd --help" into "perf help cmd" */
391 	if (argc > 1 && !strcmp(argv[1], "--help")) {
392 		argv[1] = argv[0];
393 		argv[0] = cmd = "help";
394 	}
395 
396 	for (i = 0; i < ARRAY_SIZE(commands); i++) {
397 		struct cmd_struct *p = commands+i;
398 		if (strcmp(p->cmd, cmd))
399 			continue;
400 		exit(run_builtin(p, argc, argv));
401 	}
402 }
403 
404 static void execv_dashed_external(const char **argv)
405 {
406 	struct strbuf cmd = STRBUF_INIT;
407 	const char *tmp;
408 	int status;
409 
410 	strbuf_addf(&cmd, "perf-%s", argv[0]);
411 
412 	/*
413 	 * argv[0] must be the perf command, but the argv array
414 	 * belongs to the caller, and may be reused in
415 	 * subsequent loop iterations. Save argv[0] and
416 	 * restore it on error.
417 	 */
418 	tmp = argv[0];
419 	argv[0] = cmd.buf;
420 
421 	/*
422 	 * if we fail because the command is not found, it is
423 	 * OK to return. Otherwise, we just pass along the status code.
424 	 */
425 	status = run_command_v_opt(argv, 0);
426 	if (status != -ERR_RUN_COMMAND_EXEC) {
427 		if (IS_RUN_COMMAND_ERR(status))
428 			die("unable to run '%s'", argv[0]);
429 		exit(-status);
430 	}
431 	errno = ENOENT; /* as if we called execvp */
432 
433 	argv[0] = tmp;
434 
435 	strbuf_release(&cmd);
436 }
437 
438 static int run_argv(int *argcp, const char ***argv)
439 {
440 	int done_alias = 0;
441 
442 	while (1) {
443 		/* See if it's an internal command */
444 		handle_internal_command(*argcp, *argv);
445 
446 		/* .. then try the external ones */
447 		execv_dashed_external(*argv);
448 
449 		/* It could be an alias -- this works around the insanity
450 		 * of overriding "perf log" with "perf show" by having
451 		 * alias.log = show
452 		 */
453 		if (done_alias || !handle_alias(argcp, argv))
454 			break;
455 		done_alias = 1;
456 	}
457 
458 	return done_alias;
459 }
460 
461 static void pthread__block_sigwinch(void)
462 {
463 	sigset_t set;
464 
465 	sigemptyset(&set);
466 	sigaddset(&set, SIGWINCH);
467 	pthread_sigmask(SIG_BLOCK, &set, NULL);
468 }
469 
470 void pthread__unblock_sigwinch(void)
471 {
472 	sigset_t set;
473 
474 	sigemptyset(&set);
475 	sigaddset(&set, SIGWINCH);
476 	pthread_sigmask(SIG_UNBLOCK, &set, NULL);
477 }
478 
479 int main(int argc, const char **argv)
480 {
481 	const char *cmd;
482 	char sbuf[STRERR_BUFSIZE];
483 
484 	/* The page_size is placed in util object. */
485 	page_size = sysconf(_SC_PAGE_SIZE);
486 	cacheline_size = sysconf(_SC_LEVEL1_DCACHE_LINESIZE);
487 
488 	cmd = perf_extract_argv0_path(argv[0]);
489 	if (!cmd)
490 		cmd = "perf-help";
491 	/* get debugfs mount point from /proc/mounts */
492 	perf_debugfs_mount(NULL);
493 	/*
494 	 * "perf-xxxx" is the same as "perf xxxx", but we obviously:
495 	 *
496 	 *  - cannot take flags in between the "perf" and the "xxxx".
497 	 *  - cannot execute it externally (since it would just do
498 	 *    the same thing over again)
499 	 *
500 	 * So we just directly call the internal command handler, and
501 	 * die if that one cannot handle it.
502 	 */
503 	if (!prefixcmp(cmd, "perf-")) {
504 		cmd += 5;
505 		argv[0] = cmd;
506 		handle_internal_command(argc, argv);
507 		fprintf(stderr, "cannot handle %s internally", cmd);
508 		goto out;
509 	}
510 	if (!prefixcmp(cmd, "trace")) {
511 #ifdef HAVE_LIBAUDIT_SUPPORT
512 		set_buildid_dir(NULL);
513 		setup_path();
514 		argv[0] = "trace";
515 		return cmd_trace(argc, argv, NULL);
516 #else
517 		fprintf(stderr,
518 			"trace command not available: missing audit-libs devel package at build time.\n");
519 		goto out;
520 #endif
521 	}
522 	/* Look for flags.. */
523 	argv++;
524 	argc--;
525 	handle_options(&argv, &argc, NULL);
526 	commit_pager_choice();
527 	set_buildid_dir(NULL);
528 
529 	if (argc > 0) {
530 		if (!prefixcmp(argv[0], "--"))
531 			argv[0] += 2;
532 	} else {
533 		/* The user didn't specify a command; give them help */
534 		printf("\n usage: %s\n\n", perf_usage_string);
535 		list_common_cmds_help();
536 		printf("\n %s\n\n", perf_more_info_string);
537 		goto out;
538 	}
539 	cmd = argv[0];
540 
541 	test_attr__init();
542 
543 	/*
544 	 * We use PATH to find perf commands, but we prepend some higher
545 	 * precedence paths: the "--exec-path" option, the PERF_EXEC_PATH
546 	 * environment, and the $(perfexecdir) from the Makefile at build
547 	 * time.
548 	 */
549 	setup_path();
550 	/*
551 	 * Block SIGWINCH notifications so that the thread that wants it can
552 	 * unblock and get syscalls like select interrupted instead of waiting
553 	 * forever while the signal goes to some other non interested thread.
554 	 */
555 	pthread__block_sigwinch();
556 
557 	while (1) {
558 		static int done_help;
559 		int was_alias = run_argv(&argc, &argv);
560 
561 		if (errno != ENOENT)
562 			break;
563 
564 		if (was_alias) {
565 			fprintf(stderr, "Expansion of alias '%s' failed; "
566 				"'%s' is not a perf-command\n",
567 				cmd, argv[0]);
568 			goto out;
569 		}
570 		if (!done_help) {
571 			cmd = argv[0] = help_unknown_cmd(cmd);
572 			done_help = 1;
573 		} else
574 			break;
575 	}
576 
577 	fprintf(stderr, "Failed to run command '%s': %s\n",
578 		cmd, strerror_r(errno, sbuf, sizeof(sbuf)));
579 out:
580 	return 1;
581 }
582