xref: /linux/tools/perf/perf.c (revision 24bce201d79807b668bf9d9e0aca801c5c0d5f78) 
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 "util/bpf-loader.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 const char perf_usage_string[] =
43 	"perf [--version] [--help] [OPTIONS] COMMAND [ARGS]";
44 
45 const char perf_more_info_string[] =
46 	"See 'perf help COMMAND' for more information on a specific command.";
47 
48 static int use_pager = -1;
49 const char *input_name;
50 
51 struct cmd_struct {
52 	const char *cmd;
53 	int (*fn)(int, const char **);
54 	int option;
55 };
56 
57 static struct cmd_struct commands[] = {
58 	{ "archive",	NULL,	0 },
59 	{ "buildid-cache", cmd_buildid_cache, 0 },
60 	{ "buildid-list", cmd_buildid_list, 0 },
61 	{ "config",	cmd_config,	0 },
62 	{ "c2c",	cmd_c2c,	0 },
63 	{ "diff",	cmd_diff,	0 },
64 	{ "evlist",	cmd_evlist,	0 },
65 	{ "help",	cmd_help,	0 },
66 	{ "iostat",	NULL,	0 },
67 	{ "kallsyms",	cmd_kallsyms,	0 },
68 	{ "list",	cmd_list,	0 },
69 	{ "record",	cmd_record,	0 },
70 	{ "report",	cmd_report,	0 },
71 	{ "bench",	cmd_bench,	0 },
72 	{ "stat",	cmd_stat,	0 },
73 	{ "timechart",	cmd_timechart,	0 },
74 	{ "top",	cmd_top,	0 },
75 	{ "annotate",	cmd_annotate,	0 },
76 	{ "version",	cmd_version,	0 },
77 	{ "script",	cmd_script,	0 },
78 	{ "sched",	cmd_sched,	0 },
79 #ifdef HAVE_LIBELF_SUPPORT
80 	{ "probe",	cmd_probe,	0 },
81 #endif
82 	{ "kmem",	cmd_kmem,	0 },
83 	{ "lock",	cmd_lock,	0 },
84 	{ "kvm",	cmd_kvm,	0 },
85 	{ "test",	cmd_test,	0 },
86 #if 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 };
95 
96 struct pager_config {
97 	const char *cmd;
98 	int val;
99 };
100 
101 static int pager_command_config(const char *var, const char *value, void *data)
102 {
103 	struct pager_config *c = data;
104 	if (strstarts(var, "pager.") && !strcmp(var + 6, c->cmd))
105 		c->val = perf_config_bool(var, value);
106 	return 0;
107 }
108 
109 /* returns 0 for "no pager", 1 for "use pager", and -1 for "not specified" */
110 static int check_pager_config(const char *cmd)
111 {
112 	int err;
113 	struct pager_config c;
114 	c.cmd = cmd;
115 	c.val = -1;
116 	err = perf_config(pager_command_config, &c);
117 	return err ?: c.val;
118 }
119 
120 static int browser_command_config(const char *var, const char *value, void *data)
121 {
122 	struct pager_config *c = data;
123 	if (strstarts(var, "tui.") && !strcmp(var + 4, c->cmd))
124 		c->val = perf_config_bool(var, value);
125 	if (strstarts(var, "gtk.") && !strcmp(var + 4, c->cmd))
126 		c->val = perf_config_bool(var, value) ? 2 : 0;
127 	return 0;
128 }
129 
130 /*
131  * returns 0 for "no tui", 1 for "use tui", 2 for "use gtk",
132  * and -1 for "not specified"
133  */
134 static int check_browser_config(const char *cmd)
135 {
136 	int err;
137 	struct pager_config c;
138 	c.cmd = cmd;
139 	c.val = -1;
140 	err = perf_config(browser_command_config, &c);
141 	return err ?: c.val;
142 }
143 
144 static void commit_pager_choice(void)
145 {
146 	switch (use_pager) {
147 	case 0:
148 		setenv(PERF_PAGER_ENVIRONMENT, "cat", 1);
149 		break;
150 	case 1:
151 		/* setup_pager(); */
152 		break;
153 	default:
154 		break;
155 	}
156 }
157 
158 struct option options[] = {
159 	OPT_ARGUMENT("help", "help"),
160 	OPT_ARGUMENT("version", "version"),
161 	OPT_ARGUMENT("exec-path", "exec-path"),
162 	OPT_ARGUMENT("html-path", "html-path"),
163 	OPT_ARGUMENT("paginate", "paginate"),
164 	OPT_ARGUMENT("no-pager", "no-pager"),
165 	OPT_ARGUMENT("debugfs-dir", "debugfs-dir"),
166 	OPT_ARGUMENT("buildid-dir", "buildid-dir"),
167 	OPT_ARGUMENT("list-cmds", "list-cmds"),
168 	OPT_ARGUMENT("list-opts", "list-opts"),
169 	OPT_ARGUMENT("debug", "debug"),
170 	OPT_END()
171 };
172 
173 static int handle_options(const char ***argv, int *argc, int *envchanged)
174 {
175 	int handled = 0;
176 
177 	while (*argc > 0) {
178 		const char *cmd = (*argv)[0];
179 		if (cmd[0] != '-')
180 			break;
181 
182 		/*
183 		 * For legacy reasons, the "version" and "help"
184 		 * commands can be written with "--" prepended
185 		 * to make them look like flags.
186 		 */
187 		if (!strcmp(cmd, "--help") || !strcmp(cmd, "--version"))
188 			break;
189 
190 		/*
191 		 * Shortcut for '-h' and '-v' options to invoke help
192 		 * and version command.
193 		 */
194 		if (!strcmp(cmd, "-h")) {
195 			(*argv)[0] = "--help";
196 			break;
197 		}
198 
199 		if (!strcmp(cmd, "-v")) {
200 			(*argv)[0] = "--version";
201 			break;
202 		}
203 
204 		if (!strcmp(cmd, "-vv")) {
205 			(*argv)[0] = "version";
206 			version_verbose = 1;
207 			break;
208 		}
209 
210 		/*
211 		 * Check remaining flags.
212 		 */
213 		if (strstarts(cmd, CMD_EXEC_PATH)) {
214 			cmd += strlen(CMD_EXEC_PATH);
215 			if (*cmd == '=')
216 				set_argv_exec_path(cmd + 1);
217 			else {
218 				puts(get_argv_exec_path());
219 				exit(0);
220 			}
221 		} else if (!strcmp(cmd, "--html-path")) {
222 			puts(system_path(PERF_HTML_PATH));
223 			exit(0);
224 		} else if (!strcmp(cmd, "-p") || !strcmp(cmd, "--paginate")) {
225 			use_pager = 1;
226 		} else if (!strcmp(cmd, "--no-pager")) {
227 			use_pager = 0;
228 			if (envchanged)
229 				*envchanged = 1;
230 		} else if (!strcmp(cmd, "--debugfs-dir")) {
231 			if (*argc < 2) {
232 				fprintf(stderr, "No directory given for --debugfs-dir.\n");
233 				usage(perf_usage_string);
234 			}
235 			tracing_path_set((*argv)[1]);
236 			if (envchanged)
237 				*envchanged = 1;
238 			(*argv)++;
239 			(*argc)--;
240 		} else if (!strcmp(cmd, "--buildid-dir")) {
241 			if (*argc < 2) {
242 				fprintf(stderr, "No directory given for --buildid-dir.\n");
243 				usage(perf_usage_string);
244 			}
245 			set_buildid_dir((*argv)[1]);
246 			if (envchanged)
247 				*envchanged = 1;
248 			(*argv)++;
249 			(*argc)--;
250 		} else if (strstarts(cmd, CMD_DEBUGFS_DIR)) {
251 			tracing_path_set(cmd + strlen(CMD_DEBUGFS_DIR));
252 			fprintf(stderr, "dir: %s\n", tracing_path_mount());
253 			if (envchanged)
254 				*envchanged = 1;
255 		} else if (!strcmp(cmd, "--list-cmds")) {
256 			unsigned int i;
257 
258 			for (i = 0; i < ARRAY_SIZE(commands); i++) {
259 				struct cmd_struct *p = commands+i;
260 				printf("%s ", p->cmd);
261 			}
262 			putchar('\n');
263 			exit(0);
264 		} else if (!strcmp(cmd, "--list-opts")) {
265 			unsigned int i;
266 
267 			for (i = 0; i < ARRAY_SIZE(options)-1; i++) {
268 				struct option *p = options+i;
269 				printf("--%s ", p->long_name);
270 			}
271 			putchar('\n');
272 			exit(0);
273 		} else if (!strcmp(cmd, "--debug")) {
274 			if (*argc < 2) {
275 				fprintf(stderr, "No variable specified for --debug.\n");
276 				usage(perf_usage_string);
277 			}
278 			if (perf_debug_option((*argv)[1]))
279 				usage(perf_usage_string);
280 
281 			(*argv)++;
282 			(*argc)--;
283 		} else {
284 			fprintf(stderr, "Unknown option: %s\n", cmd);
285 			usage(perf_usage_string);
286 		}
287 
288 		(*argv)++;
289 		(*argc)--;
290 		handled++;
291 	}
292 	return handled;
293 }
294 
295 #define RUN_SETUP	(1<<0)
296 #define USE_PAGER	(1<<1)
297 
298 static int run_builtin(struct cmd_struct *p, int argc, const char **argv)
299 {
300 	int status;
301 	struct stat st;
302 	char sbuf[STRERR_BUFSIZE];
303 
304 	if (use_browser == -1)
305 		use_browser = check_browser_config(p->cmd);
306 
307 	if (use_pager == -1 && p->option & RUN_SETUP)
308 		use_pager = check_pager_config(p->cmd);
309 	if (use_pager == -1 && p->option & USE_PAGER)
310 		use_pager = 1;
311 	commit_pager_choice();
312 
313 	perf_env__init(&perf_env);
314 	perf_env__set_cmdline(&perf_env, argc, argv);
315 	status = p->fn(argc, argv);
316 	perf_config__exit();
317 	exit_browser(status);
318 	perf_env__exit(&perf_env);
319 	bpf__clear();
320 
321 	if (status)
322 		return status & 0xff;
323 
324 	/* Somebody closed stdout? */
325 	if (fstat(fileno(stdout), &st))
326 		return 0;
327 	/* Ignore write errors for pipes and sockets.. */
328 	if (S_ISFIFO(st.st_mode) || S_ISSOCK(st.st_mode))
329 		return 0;
330 
331 	status = 1;
332 	/* Check for ENOSPC and EIO errors.. */
333 	if (fflush(stdout)) {
334 		fprintf(stderr, "write failure on standard output: %s",
335 			str_error_r(errno, sbuf, sizeof(sbuf)));
336 		goto out;
337 	}
338 	if (ferror(stdout)) {
339 		fprintf(stderr, "unknown write failure on standard output");
340 		goto out;
341 	}
342 	if (fclose(stdout)) {
343 		fprintf(stderr, "close failed on standard output: %s",
344 			str_error_r(errno, sbuf, sizeof(sbuf)));
345 		goto out;
346 	}
347 	status = 0;
348 out:
349 	return status;
350 }
351 
352 static void handle_internal_command(int argc, const char **argv)
353 {
354 	const char *cmd = argv[0];
355 	unsigned int i;
356 
357 	/* Turn "perf cmd --help" into "perf help cmd" */
358 	if (argc > 1 && !strcmp(argv[1], "--help")) {
359 		argv[1] = argv[0];
360 		argv[0] = cmd = "help";
361 	}
362 
363 	for (i = 0; i < ARRAY_SIZE(commands); i++) {
364 		struct cmd_struct *p = commands+i;
365 		if (p->fn == NULL)
366 			continue;
367 		if (strcmp(p->cmd, cmd))
368 			continue;
369 		exit(run_builtin(p, argc, argv));
370 	}
371 }
372 
373 static void execv_dashed_external(const char **argv)
374 {
375 	char *cmd;
376 	const char *tmp;
377 	int status;
378 
379 	if (asprintf(&cmd, "perf-%s", argv[0]) < 0)
380 		goto do_die;
381 
382 	/*
383 	 * argv[0] must be the perf command, but the argv array
384 	 * belongs to the caller, and may be reused in
385 	 * subsequent loop iterations. Save argv[0] and
386 	 * restore it on error.
387 	 */
388 	tmp = argv[0];
389 	argv[0] = cmd;
390 
391 	/*
392 	 * if we fail because the command is not found, it is
393 	 * OK to return. Otherwise, we just pass along the status code.
394 	 */
395 	status = run_command_v_opt(argv, 0);
396 	if (status != -ERR_RUN_COMMAND_EXEC) {
397 		if (IS_RUN_COMMAND_ERR(status)) {
398 do_die:
399 			pr_err("FATAL: unable to run '%s'", argv[0]);
400 			status = -128;
401 		}
402 		exit(-status);
403 	}
404 	errno = ENOENT; /* as if we called execvp */
405 
406 	argv[0] = tmp;
407 	zfree(&cmd);
408 }
409 
410 static int run_argv(int *argcp, const char ***argv)
411 {
412 	/* See if it's an internal command */
413 	handle_internal_command(*argcp, *argv);
414 
415 	/* .. then try the external ones */
416 	execv_dashed_external(*argv);
417 	return 0;
418 }
419 
420 static void pthread__block_sigwinch(void)
421 {
422 	sigset_t set;
423 
424 	sigemptyset(&set);
425 	sigaddset(&set, SIGWINCH);
426 	pthread_sigmask(SIG_BLOCK, &set, NULL);
427 }
428 
429 void pthread__unblock_sigwinch(void)
430 {
431 	sigset_t set;
432 
433 	sigemptyset(&set);
434 	sigaddset(&set, SIGWINCH);
435 	pthread_sigmask(SIG_UNBLOCK, &set, NULL);
436 }
437 
438 static int libperf_print(enum libperf_print_level level,
439 			 const char *fmt, va_list ap)
440 {
441 	return veprintf(level, verbose, fmt, ap);
442 }
443 
444 int main(int argc, const char **argv)
445 {
446 	int err;
447 	const char *cmd;
448 	char sbuf[STRERR_BUFSIZE];
449 
450 	perf_debug_setup();
451 
452 	/* libsubcmd init */
453 	exec_cmd_init("perf", PREFIX, PERF_EXEC_PATH, EXEC_PATH_ENVIRONMENT);
454 	pager_init(PERF_PAGER_ENVIRONMENT);
455 
456 	libperf_init(libperf_print);
457 
458 	cmd = extract_argv0_path(argv[0]);
459 	if (!cmd)
460 		cmd = "perf-help";
461 
462 	srandom(time(NULL));
463 
464 	/* Setting $PERF_CONFIG makes perf read _only_ the given config file. */
465 	config_exclusive_filename = getenv("PERF_CONFIG");
466 
467 	err = perf_config(perf_default_config, NULL);
468 	if (err)
469 		return err;
470 	set_buildid_dir(NULL);
471 
472 	/*
473 	 * "perf-xxxx" is the same as "perf xxxx", but we obviously:
474 	 *
475 	 *  - cannot take flags in between the "perf" and the "xxxx".
476 	 *  - cannot execute it externally (since it would just do
477 	 *    the same thing over again)
478 	 *
479 	 * So we just directly call the internal command handler. If that one
480 	 * fails to handle this, then maybe we just run a renamed perf binary
481 	 * that contains a dash in its name. To handle this scenario, we just
482 	 * fall through and ignore the "xxxx" part of the command string.
483 	 */
484 	if (strstarts(cmd, "perf-")) {
485 		cmd += 5;
486 		argv[0] = cmd;
487 		handle_internal_command(argc, argv);
488 		/*
489 		 * If the command is handled, the above function does not
490 		 * return undo changes and fall through in such a case.
491 		 */
492 		cmd -= 5;
493 		argv[0] = cmd;
494 	}
495 	if (strstarts(cmd, "trace")) {
496 #if defined(HAVE_LIBAUDIT_SUPPORT) || defined(HAVE_SYSCALL_TABLE_SUPPORT)
497 		setup_path();
498 		argv[0] = "trace";
499 		return cmd_trace(argc, argv);
500 #else
501 		fprintf(stderr,
502 			"trace command not available: missing audit-libs devel package at build time.\n");
503 		goto out;
504 #endif
505 	}
506 	/* Look for flags.. */
507 	argv++;
508 	argc--;
509 	handle_options(&argv, &argc, NULL);
510 	commit_pager_choice();
511 
512 	if (argc > 0) {
513 		if (strstarts(argv[0], "--"))
514 			argv[0] += 2;
515 	} else {
516 		/* The user didn't specify a command; give them help */
517 		printf("\n usage: %s\n\n", perf_usage_string);
518 		list_common_cmds_help();
519 		printf("\n %s\n\n", perf_more_info_string);
520 		goto out;
521 	}
522 	cmd = argv[0];
523 
524 	test_attr__init();
525 
526 	/*
527 	 * We use PATH to find perf commands, but we prepend some higher
528 	 * precedence paths: the "--exec-path" option, the PERF_EXEC_PATH
529 	 * environment, and the $(perfexecdir) from the Makefile at build
530 	 * time.
531 	 */
532 	setup_path();
533 	/*
534 	 * Block SIGWINCH notifications so that the thread that wants it can
535 	 * unblock and get syscalls like select interrupted instead of waiting
536 	 * forever while the signal goes to some other non interested thread.
537 	 */
538 	pthread__block_sigwinch();
539 
540 	while (1) {
541 		static int done_help;
542 
543 		run_argv(&argc, &argv);
544 
545 		if (errno != ENOENT)
546 			break;
547 
548 		if (!done_help) {
549 			cmd = argv[0] = help_unknown_cmd(cmd);
550 			done_help = 1;
551 		} else
552 			break;
553 	}
554 
555 	fprintf(stderr, "Failed to run command '%s': %s\n",
556 		cmd, str_error_r(errno, sbuf, sizeof(sbuf)));
557 out:
558 	return 1;
559 }
560