xref: /linux/tools/perf/perf.c (revision 257ca10c7317d4a424e48bb95d14ca53a1f1dd6f)
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/debug.h"
22 #include "util/event.h"
23 #include "util/util.h" // usage()
24 #include "ui/ui.h"
25 #include "perf-sys.h"
26 #include <api/fs/fs.h>
27 #include <api/fs/tracing_path.h>
28 #include <perf/core.h>
29 #include <errno.h>
30 #include <pthread.h>
31 #include <signal.h>
32 #include <stdlib.h>
33 #include <time.h>
34 #include <sys/types.h>
35 #include <sys/stat.h>
36 #include <unistd.h>
37 #include <linux/kernel.h>
38 #include <linux/string.h>
39 #include <linux/zalloc.h>
40 
41 static int use_pager = -1;
42 static FILE *debug_fp = NULL;
43 
44 struct cmd_struct {
45 	const char *cmd;
46 	int (*fn)(int, const char **);
47 	int option;
48 };
49 
50 static struct cmd_struct commands[] = {
51 	{ "archive",	NULL,	0 },
52 	{ "buildid-cache", cmd_buildid_cache, 0 },
53 	{ "buildid-list", cmd_buildid_list, 0 },
54 	{ "config",	cmd_config,	0 },
55 	{ "c2c",	cmd_c2c,	0 },
56 	{ "diff",	cmd_diff,	0 },
57 	{ "evlist",	cmd_evlist,	0 },
58 	{ "help",	cmd_help,	0 },
59 	{ "iostat",	NULL,	0 },
60 	{ "kallsyms",	cmd_kallsyms,	0 },
61 	{ "list",	cmd_list,	0 },
62 	{ "record",	cmd_record,	0 },
63 	{ "report",	cmd_report,	0 },
64 	{ "bench",	cmd_bench,	0 },
65 	{ "stat",	cmd_stat,	0 },
66 #ifdef HAVE_LIBTRACEEVENT
67 	{ "timechart",	cmd_timechart,	0 },
68 #endif
69 	{ "top",	cmd_top,	0 },
70 	{ "annotate",	cmd_annotate,	0 },
71 	{ "version",	cmd_version,	0 },
72 	{ "script",	cmd_script,	0 },
73 #ifdef HAVE_LIBTRACEEVENT
74 	{ "sched",	cmd_sched,	0 },
75 #endif
76 #ifdef HAVE_LIBELF_SUPPORT
77 	{ "probe",	cmd_probe,	0 },
78 #endif
79 #ifdef HAVE_LIBTRACEEVENT
80 	{ "kmem",	cmd_kmem,	0 },
81 	{ "lock",	cmd_lock,	0 },
82 #endif
83 	{ "kvm",	cmd_kvm,	0 },
84 	{ "test",	cmd_test,	0 },
85 #if defined(HAVE_LIBTRACEEVENT) && (defined(HAVE_LIBAUDIT_SUPPORT) || defined(HAVE_SYSCALL_TABLE_SUPPORT))
86 	{ "trace",	cmd_trace,	0 },
87 #endif
88 	{ "inject",	cmd_inject,	0 },
89 	{ "mem",	cmd_mem,	0 },
90 	{ "data",	cmd_data,	0 },
91 	{ "ftrace",	cmd_ftrace,	0 },
92 	{ "daemon",	cmd_daemon,	0 },
93 #ifdef HAVE_LIBTRACEEVENT
94 	{ "kwork",	cmd_kwork,	0 },
95 #endif
96 };
97 
98 struct pager_config {
99 	const char *cmd;
100 	int val;
101 };
102 
103 static bool same_cmd_with_prefix(const char *var, struct pager_config *c,
104 				  const char *header)
105 {
106 	return (strstarts(var, header) && !strcmp(var + strlen(header), c->cmd));
107 }
108 
109 static int pager_command_config(const char *var, const char *value, void *data)
110 {
111 	struct pager_config *c = data;
112 	if (same_cmd_with_prefix(var, c, "pager."))
113 		c->val = perf_config_bool(var, value);
114 	return 0;
115 }
116 
117 /* returns 0 for "no pager", 1 for "use pager", and -1 for "not specified" */
118 static int check_pager_config(const char *cmd)
119 {
120 	int err;
121 	struct pager_config c;
122 	c.cmd = cmd;
123 	c.val = -1;
124 	err = perf_config(pager_command_config, &c);
125 	return err ?: c.val;
126 }
127 
128 static int browser_command_config(const char *var, const char *value, void *data)
129 {
130 	struct pager_config *c = data;
131 	if (same_cmd_with_prefix(var, c, "tui."))
132 		c->val = perf_config_bool(var, value);
133 	if (same_cmd_with_prefix(var, c, "gtk."))
134 		c->val = perf_config_bool(var, value) ? 2 : 0;
135 	return 0;
136 }
137 
138 /*
139  * returns 0 for "no tui", 1 for "use tui", 2 for "use gtk",
140  * and -1 for "not specified"
141  */
142 static int check_browser_config(const char *cmd)
143 {
144 	int err;
145 	struct pager_config c;
146 	c.cmd = cmd;
147 	c.val = -1;
148 	err = perf_config(browser_command_config, &c);
149 	return err ?: c.val;
150 }
151 
152 static void commit_pager_choice(void)
153 {
154 	switch (use_pager) {
155 	case 0:
156 		setenv(PERF_PAGER_ENVIRONMENT, "cat", 1);
157 		break;
158 	case 1:
159 		/* setup_pager(); */
160 		break;
161 	default:
162 		break;
163 	}
164 }
165 
166 static int set_debug_file(const char *path)
167 {
168 	debug_fp = fopen(path, "w");
169 	if (!debug_fp) {
170 		fprintf(stderr, "Open debug file '%s' failed: %s\n",
171 			path, strerror(errno));
172 		return -1;
173 	}
174 
175 	debug_set_file(debug_fp);
176 	return 0;
177 }
178 
179 struct option options[] = {
180 	OPT_ARGUMENT("help", "help"),
181 	OPT_ARGUMENT("version", "version"),
182 	OPT_ARGUMENT("exec-path", "exec-path"),
183 	OPT_ARGUMENT("html-path", "html-path"),
184 	OPT_ARGUMENT("paginate", "paginate"),
185 	OPT_ARGUMENT("no-pager", "no-pager"),
186 	OPT_ARGUMENT("debugfs-dir", "debugfs-dir"),
187 	OPT_ARGUMENT("buildid-dir", "buildid-dir"),
188 	OPT_ARGUMENT("list-cmds", "list-cmds"),
189 	OPT_ARGUMENT("list-opts", "list-opts"),
190 	OPT_ARGUMENT("debug", "debug"),
191 	OPT_ARGUMENT("debug-file", "debug-file"),
192 	OPT_END()
193 };
194 
195 static int handle_options(const char ***argv, int *argc, int *envchanged)
196 {
197 	int handled = 0;
198 
199 	while (*argc > 0) {
200 		const char *cmd = (*argv)[0];
201 		if (cmd[0] != '-')
202 			break;
203 
204 		/*
205 		 * For legacy reasons, the "version" and "help"
206 		 * commands can be written with "--" prepended
207 		 * to make them look like flags.
208 		 */
209 		if (!strcmp(cmd, "--help") || !strcmp(cmd, "--version"))
210 			break;
211 
212 		/*
213 		 * Shortcut for '-h' and '-v' options to invoke help
214 		 * and version command.
215 		 */
216 		if (!strcmp(cmd, "-h")) {
217 			(*argv)[0] = "--help";
218 			break;
219 		}
220 
221 		if (!strcmp(cmd, "-v")) {
222 			(*argv)[0] = "--version";
223 			break;
224 		}
225 
226 		if (!strcmp(cmd, "-vv")) {
227 			(*argv)[0] = "version";
228 			verbose = 1;
229 			break;
230 		}
231 
232 		/*
233 		 * Check remaining flags.
234 		 */
235 		if (strstarts(cmd, CMD_EXEC_PATH)) {
236 			cmd += strlen(CMD_EXEC_PATH);
237 			if (*cmd == '=')
238 				set_argv_exec_path(cmd + 1);
239 			else {
240 				puts(get_argv_exec_path());
241 				exit(0);
242 			}
243 		} else if (!strcmp(cmd, "--html-path")) {
244 			puts(system_path(PERF_HTML_PATH));
245 			exit(0);
246 		} else if (!strcmp(cmd, "-p") || !strcmp(cmd, "--paginate")) {
247 			use_pager = 1;
248 		} else if (!strcmp(cmd, "--no-pager")) {
249 			use_pager = 0;
250 			if (envchanged)
251 				*envchanged = 1;
252 		} else if (!strcmp(cmd, "--debugfs-dir")) {
253 			if (*argc < 2) {
254 				fprintf(stderr, "No directory given for --debugfs-dir.\n");
255 				usage(perf_usage_string);
256 			}
257 			tracing_path_set((*argv)[1]);
258 			if (envchanged)
259 				*envchanged = 1;
260 			(*argv)++;
261 			(*argc)--;
262 		} else if (!strcmp(cmd, "--buildid-dir")) {
263 			if (*argc < 2) {
264 				fprintf(stderr, "No directory given for --buildid-dir.\n");
265 				usage(perf_usage_string);
266 			}
267 			set_buildid_dir((*argv)[1]);
268 			if (envchanged)
269 				*envchanged = 1;
270 			(*argv)++;
271 			(*argc)--;
272 		} else if (strstarts(cmd, CMD_DEBUGFS_DIR)) {
273 			tracing_path_set(cmd + strlen(CMD_DEBUGFS_DIR));
274 			fprintf(stderr, "dir: %s\n", tracing_path_mount());
275 			if (envchanged)
276 				*envchanged = 1;
277 		} else if (!strcmp(cmd, "--list-cmds")) {
278 			unsigned int i;
279 
280 			for (i = 0; i < ARRAY_SIZE(commands); i++) {
281 				struct cmd_struct *p = commands+i;
282 				printf("%s ", p->cmd);
283 			}
284 			putchar('\n');
285 			exit(0);
286 		} else if (!strcmp(cmd, "--list-opts")) {
287 			unsigned int i;
288 
289 			for (i = 0; i < ARRAY_SIZE(options)-1; i++) {
290 				struct option *p = options+i;
291 				printf("--%s ", p->long_name);
292 			}
293 			putchar('\n');
294 			exit(0);
295 		} else if (!strcmp(cmd, "--debug")) {
296 			if (*argc < 2) {
297 				fprintf(stderr, "No variable specified for --debug.\n");
298 				usage(perf_usage_string);
299 			}
300 			if (perf_debug_option((*argv)[1]))
301 				usage(perf_usage_string);
302 
303 			(*argv)++;
304 			(*argc)--;
305 		} else if (!strcmp(cmd, "--debug-file")) {
306 			if (*argc < 2) {
307 				fprintf(stderr, "No path given for --debug-file.\n");
308 				usage(perf_usage_string);
309 			}
310 
311 			if (set_debug_file((*argv)[1]))
312 				usage(perf_usage_string);
313 
314 			(*argv)++;
315 			(*argc)--;
316 
317 		} else {
318 			fprintf(stderr, "Unknown option: %s\n", cmd);
319 			usage(perf_usage_string);
320 		}
321 
322 		(*argv)++;
323 		(*argc)--;
324 		handled++;
325 	}
326 	return handled;
327 }
328 
329 #define RUN_SETUP	(1<<0)
330 #define USE_PAGER	(1<<1)
331 
332 static int run_builtin(struct cmd_struct *p, int argc, const char **argv)
333 {
334 	int status;
335 	struct stat st;
336 	char sbuf[STRERR_BUFSIZE];
337 
338 	if (use_browser == -1)
339 		use_browser = check_browser_config(p->cmd);
340 
341 	if (use_pager == -1 && p->option & RUN_SETUP)
342 		use_pager = check_pager_config(p->cmd);
343 	if (use_pager == -1 && p->option & USE_PAGER)
344 		use_pager = 1;
345 	commit_pager_choice();
346 
347 	perf_env__init(&perf_env);
348 	perf_env__set_cmdline(&perf_env, argc, argv);
349 	status = p->fn(argc, argv);
350 	perf_config__exit();
351 	exit_browser(status);
352 	perf_env__exit(&perf_env);
353 
354 	if (status)
355 		return status & 0xff;
356 
357 	/* Somebody closed stdout? */
358 	if (fstat(fileno(stdout), &st))
359 		return 0;
360 	/* Ignore write errors for pipes and sockets.. */
361 	if (S_ISFIFO(st.st_mode) || S_ISSOCK(st.st_mode))
362 		return 0;
363 
364 	status = 1;
365 	/* Check for ENOSPC and EIO errors.. */
366 	if (fflush(stdout)) {
367 		fprintf(stderr, "write failure on standard output: %s",
368 			str_error_r(errno, sbuf, sizeof(sbuf)));
369 		goto out;
370 	}
371 	if (ferror(stdout)) {
372 		fprintf(stderr, "unknown write failure on standard output");
373 		goto out;
374 	}
375 	if (fclose(stdout)) {
376 		fprintf(stderr, "close failed on standard output: %s",
377 			str_error_r(errno, sbuf, sizeof(sbuf)));
378 		goto out;
379 	}
380 	status = 0;
381 out:
382 	return status;
383 }
384 
385 static void handle_internal_command(int argc, const char **argv)
386 {
387 	const char *cmd = argv[0];
388 	unsigned int i;
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 (p->fn == NULL)
399 			continue;
400 		if (strcmp(p->cmd, cmd))
401 			continue;
402 		exit(run_builtin(p, argc, argv));
403 	}
404 }
405 
406 static void execv_dashed_external(const char **argv)
407 {
408 	char *cmd;
409 	const char *tmp;
410 	int status;
411 
412 	if (asprintf(&cmd, "perf-%s", argv[0]) < 0)
413 		goto do_die;
414 
415 	/*
416 	 * argv[0] must be the perf command, but the argv array
417 	 * belongs to the caller, and may be reused in
418 	 * subsequent loop iterations. Save argv[0] and
419 	 * restore it on error.
420 	 */
421 	tmp = argv[0];
422 	argv[0] = cmd;
423 
424 	/*
425 	 * if we fail because the command is not found, it is
426 	 * OK to return. Otherwise, we just pass along the status code.
427 	 */
428 	status = run_command_v_opt(argv, 0);
429 	if (status != -ERR_RUN_COMMAND_EXEC) {
430 		if (IS_RUN_COMMAND_ERR(status)) {
431 do_die:
432 			pr_err("FATAL: unable to run '%s'", argv[0]);
433 			status = -128;
434 		}
435 		exit(-status);
436 	}
437 	errno = ENOENT; /* as if we called execvp */
438 
439 	argv[0] = tmp;
440 	zfree(&cmd);
441 }
442 
443 static int run_argv(int *argcp, const char ***argv)
444 {
445 	/* See if it's an internal command */
446 	handle_internal_command(*argcp, *argv);
447 
448 	/* .. then try the external ones */
449 	execv_dashed_external(*argv);
450 	return 0;
451 }
452 
453 static int libperf_print(enum libperf_print_level level,
454 			 const char *fmt, va_list ap)
455 {
456 	return veprintf(level, verbose, fmt, ap);
457 }
458 
459 int main(int argc, const char **argv)
460 {
461 	int err;
462 	const char *cmd;
463 	char sbuf[STRERR_BUFSIZE];
464 
465 	perf_debug_setup();
466 
467 	/* libsubcmd init */
468 	exec_cmd_init("perf", PREFIX, PERF_EXEC_PATH, EXEC_PATH_ENVIRONMENT);
469 	pager_init(PERF_PAGER_ENVIRONMENT);
470 
471 	libperf_init(libperf_print);
472 
473 	cmd = extract_argv0_path(argv[0]);
474 	if (!cmd)
475 		cmd = "perf-help";
476 
477 	srandom(time(NULL));
478 
479 	/* Setting $PERF_CONFIG makes perf read _only_ the given config file. */
480 	config_exclusive_filename = getenv("PERF_CONFIG");
481 
482 	err = perf_config(perf_default_config, NULL);
483 	if (err)
484 		return err;
485 	set_buildid_dir(NULL);
486 
487 	/*
488 	 * "perf-xxxx" is the same as "perf xxxx", but we obviously:
489 	 *
490 	 *  - cannot take flags in between the "perf" and the "xxxx".
491 	 *  - cannot execute it externally (since it would just do
492 	 *    the same thing over again)
493 	 *
494 	 * So we just directly call the internal command handler. If that one
495 	 * fails to handle this, then maybe we just run a renamed perf binary
496 	 * that contains a dash in its name. To handle this scenario, we just
497 	 * fall through and ignore the "xxxx" part of the command string.
498 	 */
499 	if (strstarts(cmd, "perf-")) {
500 		cmd += 5;
501 		argv[0] = cmd;
502 		handle_internal_command(argc, argv);
503 		/*
504 		 * If the command is handled, the above function does not
505 		 * return undo changes and fall through in such a case.
506 		 */
507 		cmd -= 5;
508 		argv[0] = cmd;
509 	}
510 	if (strstarts(cmd, "trace")) {
511 #ifndef HAVE_LIBTRACEEVENT
512 		fprintf(stderr,
513 			"trace command not available: missing libtraceevent devel package at build time.\n");
514 		goto out;
515 #elif !defined(HAVE_LIBAUDIT_SUPPORT) && !defined(HAVE_SYSCALL_TABLE_SUPPORT)
516 		fprintf(stderr,
517 			"trace command not available: missing audit-libs devel package at build time.\n");
518 		goto out;
519 #else
520 		setup_path();
521 		argv[0] = "trace";
522 		return cmd_trace(argc, argv);
523 #endif
524 	}
525 	/* Look for flags.. */
526 	argv++;
527 	argc--;
528 	handle_options(&argv, &argc, NULL);
529 	commit_pager_choice();
530 
531 	if (argc > 0) {
532 		if (strstarts(argv[0], "--"))
533 			argv[0] += 2;
534 	} else {
535 		/* The user didn't specify a command; give them help */
536 		printf("\n usage: %s\n\n", perf_usage_string);
537 		list_common_cmds_help();
538 		printf("\n %s\n\n", perf_more_info_string);
539 		goto out;
540 	}
541 	cmd = argv[0];
542 
543 	test_attr__init();
544 
545 	/*
546 	 * We use PATH to find perf commands, but we prepend some higher
547 	 * precedence paths: the "--exec-path" option, the PERF_EXEC_PATH
548 	 * environment, and the $(perfexecdir) from the Makefile at build
549 	 * time.
550 	 */
551 	setup_path();
552 	/*
553 	 * Block SIGWINCH notifications so that the thread that wants it can
554 	 * unblock and get syscalls like select interrupted instead of waiting
555 	 * forever while the signal goes to some other non interested thread.
556 	 */
557 	pthread__block_sigwinch();
558 
559 	while (1) {
560 		static int done_help;
561 
562 		run_argv(&argc, &argv);
563 
564 		if (errno != ENOENT)
565 			break;
566 
567 		if (!done_help) {
568 			cmd = argv[0] = help_unknown_cmd(cmd);
569 			done_help = 1;
570 		} else
571 			break;
572 	}
573 
574 	fprintf(stderr, "Failed to run command '%s': %s\n",
575 		cmd, str_error_r(errno, sbuf, sizeof(sbuf)));
576 out:
577 	if (debug_fp)
578 		fclose(debug_fp);
579 
580 	return 1;
581 }
582