xref: /linux/tools/perf/perf.c (revision ab52c59103002b49f2455371e4b9c56ba3ef1781) 
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 #include "perf.h"
11 
12 #include "util/build-id.h"
13 #include "util/cache.h"
14 #include "util/env.h"
15 #include <internal/lib.h> // page_size
16 #include <subcmd/exec-cmd.h>
17 #include "util/config.h"
18 #include <subcmd/run-command.h>
19 #include "util/parse-events.h"
20 #include <subcmd/parse-options.h>
21 #include <subcmd/help.h>
22 #include "util/debug.h"
23 #include "util/event.h"
24 #include "util/util.h" // usage()
25 #include "ui/ui.h"
26 #include "perf-sys.h"
27 #include <api/fs/fs.h>
28 #include <api/fs/tracing_path.h>
29 #include <perf/core.h>
30 #include <errno.h>
31 #include <pthread.h>
32 #include <signal.h>
33 #include <stdlib.h>
34 #include <time.h>
35 #include <sys/types.h>
36 #include <sys/stat.h>
37 #include <unistd.h>
38 #include <linux/kernel.h>
39 #include <linux/string.h>
40 #include <linux/zalloc.h>
41 
42 static int use_pager = -1;
43 static FILE *debug_fp = NULL;
44 
45 struct cmd_struct {
46 	const char *cmd;
47 	int (*fn)(int, const char **);
48 	int option;
49 };
50 
51 static struct cmd_struct commands[] = {
52 	{ "archive",	NULL,	0 },
53 	{ "buildid-cache", cmd_buildid_cache, 0 },
54 	{ "buildid-list", cmd_buildid_list, 0 },
55 	{ "config",	cmd_config,	0 },
56 	{ "c2c",	cmd_c2c,	0 },
57 	{ "diff",	cmd_diff,	0 },
58 	{ "evlist",	cmd_evlist,	0 },
59 	{ "help",	cmd_help,	0 },
60 	{ "iostat",	NULL,	0 },
61 	{ "kallsyms",	cmd_kallsyms,	0 },
62 	{ "list",	cmd_list,	0 },
63 	{ "record",	cmd_record,	0 },
64 	{ "report",	cmd_report,	0 },
65 	{ "bench",	cmd_bench,	0 },
66 	{ "stat",	cmd_stat,	0 },
67 #ifdef HAVE_LIBTRACEEVENT
68 	{ "timechart",	cmd_timechart,	0 },
69 #endif
70 	{ "top",	cmd_top,	0 },
71 	{ "annotate",	cmd_annotate,	0 },
72 	{ "version",	cmd_version,	0 },
73 	{ "script",	cmd_script,	0 },
74 #ifdef HAVE_LIBTRACEEVENT
75 	{ "sched",	cmd_sched,	0 },
76 #endif
77 #ifdef HAVE_LIBELF_SUPPORT
78 	{ "probe",	cmd_probe,	0 },
79 #endif
80 #ifdef HAVE_LIBTRACEEVENT
81 	{ "kmem",	cmd_kmem,	0 },
82 	{ "lock",	cmd_lock,	0 },
83 #endif
84 	{ "kvm",	cmd_kvm,	0 },
85 	{ "test",	cmd_test,	0 },
86 #if defined(HAVE_LIBTRACEEVENT) && (defined(HAVE_LIBAUDIT_SUPPORT) || defined(HAVE_SYSCALL_TABLE_SUPPORT))
87 	{ "trace",	cmd_trace,	0 },
88 #endif
89 	{ "inject",	cmd_inject,	0 },
90 	{ "mem",	cmd_mem,	0 },
91 	{ "data",	cmd_data,	0 },
92 	{ "ftrace",	cmd_ftrace,	0 },
93 	{ "daemon",	cmd_daemon,	0 },
94 #ifdef HAVE_LIBTRACEEVENT
95 	{ "kwork",	cmd_kwork,	0 },
96 #endif
97 };
98 
99 struct pager_config {
100 	const char *cmd;
101 	int val;
102 };
103 
104 static bool same_cmd_with_prefix(const char *var, struct pager_config *c,
105 				  const char *header)
106 {
107 	return (strstarts(var, header) && !strcmp(var + strlen(header), c->cmd));
108 }
109 
110 static int pager_command_config(const char *var, const char *value, void *data)
111 {
112 	struct pager_config *c = data;
113 	if (same_cmd_with_prefix(var, c, "pager."))
114 		c->val = perf_config_bool(var, value);
115 	return 0;
116 }
117 
118 /* returns 0 for "no pager", 1 for "use pager", and -1 for "not specified" */
119 static int check_pager_config(const char *cmd)
120 {
121 	int err;
122 	struct pager_config c;
123 	c.cmd = cmd;
124 	c.val = -1;
125 	err = perf_config(pager_command_config, &c);
126 	return err ?: c.val;
127 }
128 
129 static int browser_command_config(const char *var, const char *value, void *data)
130 {
131 	struct pager_config *c = data;
132 	if (same_cmd_with_prefix(var, c, "tui."))
133 		c->val = perf_config_bool(var, value);
134 	if (same_cmd_with_prefix(var, c, "gtk."))
135 		c->val = perf_config_bool(var, value) ? 2 : 0;
136 	return 0;
137 }
138 
139 /*
140  * returns 0 for "no tui", 1 for "use tui", 2 for "use gtk",
141  * and -1 for "not specified"
142  */
143 static int check_browser_config(const char *cmd)
144 {
145 	int err;
146 	struct pager_config c;
147 	c.cmd = cmd;
148 	c.val = -1;
149 	err = perf_config(browser_command_config, &c);
150 	return err ?: c.val;
151 }
152 
153 static void commit_pager_choice(void)
154 {
155 	switch (use_pager) {
156 	case 0:
157 		setenv(PERF_PAGER_ENVIRONMENT, "cat", 1);
158 		break;
159 	case 1:
160 		/* setup_pager(); */
161 		break;
162 	default:
163 		break;
164 	}
165 }
166 
167 static int set_debug_file(const char *path)
168 {
169 	debug_fp = fopen(path, "w");
170 	if (!debug_fp) {
171 		fprintf(stderr, "Open debug file '%s' failed: %s\n",
172 			path, strerror(errno));
173 		return -1;
174 	}
175 
176 	debug_set_file(debug_fp);
177 	return 0;
178 }
179 
180 struct option options[] = {
181 	OPT_ARGUMENT("help", "help"),
182 	OPT_ARGUMENT("version", "version"),
183 	OPT_ARGUMENT("exec-path", "exec-path"),
184 	OPT_ARGUMENT("html-path", "html-path"),
185 	OPT_ARGUMENT("paginate", "paginate"),
186 	OPT_ARGUMENT("no-pager", "no-pager"),
187 	OPT_ARGUMENT("debugfs-dir", "debugfs-dir"),
188 	OPT_ARGUMENT("buildid-dir", "buildid-dir"),
189 	OPT_ARGUMENT("list-cmds", "list-cmds"),
190 	OPT_ARGUMENT("list-opts", "list-opts"),
191 	OPT_ARGUMENT("debug", "debug"),
192 	OPT_ARGUMENT("debug-file", "debug-file"),
193 	OPT_END()
194 };
195 
196 static int handle_options(const char ***argv, int *argc, int *envchanged)
197 {
198 	int handled = 0;
199 
200 	while (*argc > 0) {
201 		const char *cmd = (*argv)[0];
202 		if (cmd[0] != '-')
203 			break;
204 
205 		/*
206 		 * For legacy reasons, the "version" and "help"
207 		 * commands can be written with "--" prepended
208 		 * to make them look like flags.
209 		 */
210 		if (!strcmp(cmd, "--help") || !strcmp(cmd, "--version"))
211 			break;
212 
213 		/*
214 		 * Shortcut for '-h' and '-v' options to invoke help
215 		 * and version command.
216 		 */
217 		if (!strcmp(cmd, "-h")) {
218 			(*argv)[0] = "--help";
219 			break;
220 		}
221 
222 		if (!strcmp(cmd, "-v")) {
223 			(*argv)[0] = "--version";
224 			break;
225 		}
226 
227 		if (!strcmp(cmd, "-vv")) {
228 			(*argv)[0] = "version";
229 			verbose = 1;
230 			break;
231 		}
232 
233 		/*
234 		 * Check remaining flags.
235 		 */
236 		if (strstarts(cmd, CMD_EXEC_PATH)) {
237 			cmd += strlen(CMD_EXEC_PATH);
238 			if (*cmd == '=')
239 				set_argv_exec_path(cmd + 1);
240 			else {
241 				puts(get_argv_exec_path());
242 				exit(0);
243 			}
244 		} else if (!strcmp(cmd, "--html-path")) {
245 			puts(system_path(PERF_HTML_PATH));
246 			exit(0);
247 		} else if (!strcmp(cmd, "-p") || !strcmp(cmd, "--paginate")) {
248 			use_pager = 1;
249 		} else if (!strcmp(cmd, "--no-pager")) {
250 			use_pager = 0;
251 			if (envchanged)
252 				*envchanged = 1;
253 		} else if (!strcmp(cmd, "--debugfs-dir")) {
254 			if (*argc < 2) {
255 				fprintf(stderr, "No directory given for --debugfs-dir.\n");
256 				usage(perf_usage_string);
257 			}
258 			tracing_path_set((*argv)[1]);
259 			if (envchanged)
260 				*envchanged = 1;
261 			(*argv)++;
262 			(*argc)--;
263 		} else if (!strcmp(cmd, "--buildid-dir")) {
264 			if (*argc < 2) {
265 				fprintf(stderr, "No directory given for --buildid-dir.\n");
266 				usage(perf_usage_string);
267 			}
268 			set_buildid_dir((*argv)[1]);
269 			if (envchanged)
270 				*envchanged = 1;
271 			(*argv)++;
272 			(*argc)--;
273 		} else if (strstarts(cmd, CMD_DEBUGFS_DIR)) {
274 			tracing_path_set(cmd + strlen(CMD_DEBUGFS_DIR));
275 			fprintf(stderr, "dir: %s\n", tracing_path_mount());
276 			if (envchanged)
277 				*envchanged = 1;
278 		} else if (!strcmp(cmd, "--list-cmds")) {
279 			unsigned int i;
280 
281 			for (i = 0; i < ARRAY_SIZE(commands); i++) {
282 				struct cmd_struct *p = commands+i;
283 				printf("%s ", p->cmd);
284 			}
285 			putchar('\n');
286 			exit(0);
287 		} else if (!strcmp(cmd, "--list-opts")) {
288 			unsigned int i;
289 
290 			for (i = 0; i < ARRAY_SIZE(options)-1; i++) {
291 				struct option *p = options+i;
292 				printf("--%s ", p->long_name);
293 			}
294 			putchar('\n');
295 			exit(0);
296 		} else if (!strcmp(cmd, "--debug")) {
297 			if (*argc < 2) {
298 				fprintf(stderr, "No variable specified for --debug.\n");
299 				usage(perf_usage_string);
300 			}
301 			if (perf_debug_option((*argv)[1]))
302 				usage(perf_usage_string);
303 
304 			(*argv)++;
305 			(*argc)--;
306 		} else if (!strcmp(cmd, "--debug-file")) {
307 			if (*argc < 2) {
308 				fprintf(stderr, "No path given for --debug-file.\n");
309 				usage(perf_usage_string);
310 			}
311 
312 			if (set_debug_file((*argv)[1]))
313 				usage(perf_usage_string);
314 
315 			(*argv)++;
316 			(*argc)--;
317 
318 		} else {
319 			fprintf(stderr, "Unknown option: %s\n", cmd);
320 			usage(perf_usage_string);
321 		}
322 
323 		(*argv)++;
324 		(*argc)--;
325 		handled++;
326 	}
327 	return handled;
328 }
329 
330 #define RUN_SETUP	(1<<0)
331 #define USE_PAGER	(1<<1)
332 
333 static int run_builtin(struct cmd_struct *p, int argc, const char **argv)
334 {
335 	int status;
336 	struct stat st;
337 	char sbuf[STRERR_BUFSIZE];
338 
339 	if (use_browser == -1)
340 		use_browser = check_browser_config(p->cmd);
341 
342 	if (use_pager == -1 && p->option & RUN_SETUP)
343 		use_pager = check_pager_config(p->cmd);
344 	if (use_pager == -1 && p->option & USE_PAGER)
345 		use_pager = 1;
346 	commit_pager_choice();
347 
348 	perf_env__init(&perf_env);
349 	perf_env__set_cmdline(&perf_env, argc, argv);
350 	status = p->fn(argc, argv);
351 	perf_config__exit();
352 	exit_browser(status);
353 	perf_env__exit(&perf_env);
354 
355 	if (status)
356 		return status & 0xff;
357 
358 	/* Somebody closed stdout? */
359 	if (fstat(fileno(stdout), &st))
360 		return 0;
361 	/* Ignore write errors for pipes and sockets.. */
362 	if (S_ISFIFO(st.st_mode) || S_ISSOCK(st.st_mode))
363 		return 0;
364 
365 	status = 1;
366 	/* Check for ENOSPC and EIO errors.. */
367 	if (fflush(stdout)) {
368 		fprintf(stderr, "write failure on standard output: %s",
369 			str_error_r(errno, sbuf, sizeof(sbuf)));
370 		goto out;
371 	}
372 	if (ferror(stdout)) {
373 		fprintf(stderr, "unknown write failure on standard output");
374 		goto out;
375 	}
376 	if (fclose(stdout)) {
377 		fprintf(stderr, "close failed on standard output: %s",
378 			str_error_r(errno, sbuf, sizeof(sbuf)));
379 		goto out;
380 	}
381 	status = 0;
382 out:
383 	return status;
384 }
385 
386 static void handle_internal_command(int argc, const char **argv)
387 {
388 	const char *cmd = argv[0];
389 	unsigned int i;
390 
391 	/* Turn "perf cmd --help" into "perf help cmd" */
392 	if (argc > 1 && !strcmp(argv[1], "--help")) {
393 		argv[1] = argv[0];
394 		argv[0] = cmd = "help";
395 	}
396 
397 	for (i = 0; i < ARRAY_SIZE(commands); i++) {
398 		struct cmd_struct *p = commands+i;
399 		if (p->fn == NULL)
400 			continue;
401 		if (strcmp(p->cmd, cmd))
402 			continue;
403 		exit(run_builtin(p, argc, argv));
404 	}
405 }
406 
407 static void execv_dashed_external(const char **argv)
408 {
409 	char *cmd;
410 	const char *tmp;
411 	int status;
412 
413 	if (asprintf(&cmd, "perf-%s", argv[0]) < 0)
414 		goto do_die;
415 
416 	/*
417 	 * argv[0] must be the perf command, but the argv array
418 	 * belongs to the caller, and may be reused in
419 	 * subsequent loop iterations. Save argv[0] and
420 	 * restore it on error.
421 	 */
422 	tmp = argv[0];
423 	argv[0] = cmd;
424 
425 	/*
426 	 * if we fail because the command is not found, it is
427 	 * OK to return. Otherwise, we just pass along the status code.
428 	 */
429 	status = run_command_v_opt(argv, 0);
430 	if (status != -ERR_RUN_COMMAND_EXEC) {
431 		if (IS_RUN_COMMAND_ERR(status)) {
432 do_die:
433 			pr_err("FATAL: unable to run '%s'", argv[0]);
434 			status = -128;
435 		}
436 		exit(-status);
437 	}
438 	errno = ENOENT; /* as if we called execvp */
439 
440 	argv[0] = tmp;
441 	zfree(&cmd);
442 }
443 
444 static int run_argv(int *argcp, const char ***argv)
445 {
446 	/* See if it's an internal command */
447 	handle_internal_command(*argcp, *argv);
448 
449 	/* .. then try the external ones */
450 	execv_dashed_external(*argv);
451 	return 0;
452 }
453 
454 static int libperf_print(enum libperf_print_level level,
455 			 const char *fmt, va_list ap)
456 {
457 	return veprintf(level, verbose, fmt, ap);
458 }
459 
460 int main(int argc, const char **argv)
461 {
462 	int err, done_help = 0;
463 	const char *cmd;
464 	char sbuf[STRERR_BUFSIZE];
465 
466 	perf_debug_setup();
467 
468 	/* libsubcmd init */
469 	exec_cmd_init("perf", PREFIX, PERF_EXEC_PATH, EXEC_PATH_ENVIRONMENT);
470 	pager_init(PERF_PAGER_ENVIRONMENT);
471 
472 	libperf_init(libperf_print);
473 
474 	cmd = extract_argv0_path(argv[0]);
475 	if (!cmd)
476 		cmd = "perf-help";
477 
478 	srandom(time(NULL));
479 
480 	/* Setting $PERF_CONFIG makes perf read _only_ the given config file. */
481 	config_exclusive_filename = getenv("PERF_CONFIG");
482 
483 	err = perf_config(perf_default_config, NULL);
484 	if (err)
485 		return err;
486 	set_buildid_dir(NULL);
487 
488 	/*
489 	 * "perf-xxxx" is the same as "perf xxxx", but we obviously:
490 	 *
491 	 *  - cannot take flags in between the "perf" and the "xxxx".
492 	 *  - cannot execute it externally (since it would just do
493 	 *    the same thing over again)
494 	 *
495 	 * So we just directly call the internal command handler. If that one
496 	 * fails to handle this, then maybe we just run a renamed perf binary
497 	 * that contains a dash in its name. To handle this scenario, we just
498 	 * fall through and ignore the "xxxx" part of the command string.
499 	 */
500 	if (strstarts(cmd, "perf-")) {
501 		cmd += 5;
502 		argv[0] = cmd;
503 		handle_internal_command(argc, argv);
504 		/*
505 		 * If the command is handled, the above function does not
506 		 * return undo changes and fall through in such a case.
507 		 */
508 		cmd -= 5;
509 		argv[0] = cmd;
510 	}
511 	if (strstarts(cmd, "trace")) {
512 #ifndef HAVE_LIBTRACEEVENT
513 		fprintf(stderr,
514 			"trace command not available: missing libtraceevent devel package at build time.\n");
515 		goto out;
516 #elif !defined(HAVE_LIBAUDIT_SUPPORT) && !defined(HAVE_SYSCALL_TABLE_SUPPORT)
517 		fprintf(stderr,
518 			"trace command not available: missing audit-libs devel package at build time.\n");
519 		goto out;
520 #else
521 		setup_path();
522 		argv[0] = "trace";
523 		return cmd_trace(argc, argv);
524 #endif
525 	}
526 	/* Look for flags.. */
527 	argv++;
528 	argc--;
529 	handle_options(&argv, &argc, NULL);
530 	commit_pager_choice();
531 
532 	if (argc > 0) {
533 		if (strstarts(argv[0], "--"))
534 			argv[0] += 2;
535 	} else {
536 		/* The user didn't specify a command; give them help */
537 		printf("\n usage: %s\n\n", perf_usage_string);
538 		list_common_cmds_help();
539 		printf("\n %s\n\n", perf_more_info_string);
540 		goto out;
541 	}
542 	cmd = argv[0];
543 
544 	test_attr__init();
545 
546 	/*
547 	 * We use PATH to find perf commands, but we prepend some higher
548 	 * precedence paths: the "--exec-path" option, the PERF_EXEC_PATH
549 	 * environment, and the $(perfexecdir) from the Makefile at build
550 	 * time.
551 	 */
552 	setup_path();
553 	/*
554 	 * Block SIGWINCH notifications so that the thread that wants it can
555 	 * unblock and get syscalls like select interrupted instead of waiting
556 	 * forever while the signal goes to some other non interested thread.
557 	 */
558 	pthread__block_sigwinch();
559 
560 	while (1) {
561 		run_argv(&argc, &argv);
562 
563 		if (errno != ENOENT)
564 			break;
565 
566 		if (!done_help) {
567 			struct cmdnames main_cmds = {};
568 
569 			for (unsigned int i = 0; i < ARRAY_SIZE(commands); i++) {
570 				add_cmdname(&main_cmds,
571 					    commands[i].cmd,
572 					    strlen(commands[i].cmd));
573 			}
574 			cmd = argv[0] = help_unknown_cmd(cmd, &main_cmds);
575 			clean_cmdnames(&main_cmds);
576 			done_help = 1;
577 			if (!cmd)
578 				break;
579 		} else
580 			break;
581 	}
582 
583 	if (cmd) {
584 		fprintf(stderr, "Failed to run command '%s': %s\n",
585 			cmd, str_error_r(errno, sbuf, sizeof(sbuf)));
586 	}
587 out:
588 	if (debug_fp)
589 		fclose(debug_fp);
590 
591 	return 1;
592 }
593