xref: /linux/tools/perf/perf.c (revision 3a39d672e7f48b8d6b91a09afa4b55352773b4b5)
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 	{ "check",	cmd_check,	0 },
56 	{ "config",	cmd_config,	0 },
57 	{ "c2c",	cmd_c2c,	0 },
58 	{ "diff",	cmd_diff,	0 },
59 	{ "evlist",	cmd_evlist,	0 },
60 	{ "help",	cmd_help,	0 },
61 	{ "iostat",	NULL,	0 },
62 	{ "kallsyms",	cmd_kallsyms,	0 },
63 	{ "list",	cmd_list,	0 },
64 	{ "record",	cmd_record,	0 },
65 	{ "report",	cmd_report,	0 },
66 	{ "bench",	cmd_bench,	0 },
67 	{ "stat",	cmd_stat,	0 },
68 #ifdef HAVE_LIBTRACEEVENT
69 	{ "timechart",	cmd_timechart,	0 },
70 #endif
71 	{ "top",	cmd_top,	0 },
72 	{ "annotate",	cmd_annotate,	0 },
73 	{ "version",	cmd_version,	0 },
74 	{ "script",	cmd_script,	0 },
75 #ifdef HAVE_LIBTRACEEVENT
76 	{ "sched",	cmd_sched,	0 },
77 #endif
78 #ifdef HAVE_LIBELF_SUPPORT
79 	{ "probe",	cmd_probe,	0 },
80 #endif
81 #ifdef HAVE_LIBTRACEEVENT
82 	{ "kmem",	cmd_kmem,	0 },
83 	{ "lock",	cmd_lock,	0 },
84 #endif
85 	{ "kvm",	cmd_kvm,	0 },
86 	{ "test",	cmd_test,	0 },
87 #if defined(HAVE_LIBTRACEEVENT) && (defined(HAVE_LIBAUDIT_SUPPORT) || defined(HAVE_SYSCALL_TABLE_SUPPORT))
88 	{ "trace",	cmd_trace,	0 },
89 #endif
90 	{ "inject",	cmd_inject,	0 },
91 	{ "mem",	cmd_mem,	0 },
92 	{ "data",	cmd_data,	0 },
93 	{ "ftrace",	cmd_ftrace,	0 },
94 	{ "daemon",	cmd_daemon,	0 },
95 #ifdef HAVE_LIBTRACEEVENT
96 	{ "kwork",	cmd_kwork,	0 },
97 #endif
98 };
99 
100 struct pager_config {
101 	const char *cmd;
102 	int val;
103 };
104 
same_cmd_with_prefix(const char * var,struct pager_config * c,const char * header)105 static bool same_cmd_with_prefix(const char *var, struct pager_config *c,
106 				  const char *header)
107 {
108 	return (strstarts(var, header) && !strcmp(var + strlen(header), c->cmd));
109 }
110 
pager_command_config(const char * var,const char * value,void * data)111 static int pager_command_config(const char *var, const char *value, void *data)
112 {
113 	struct pager_config *c = data;
114 	if (same_cmd_with_prefix(var, c, "pager."))
115 		c->val = perf_config_bool(var, value);
116 	return 0;
117 }
118 
119 /* returns 0 for "no pager", 1 for "use pager", and -1 for "not specified" */
check_pager_config(const char * cmd)120 static int check_pager_config(const char *cmd)
121 {
122 	int err;
123 	struct pager_config c;
124 	c.cmd = cmd;
125 	c.val = -1;
126 	err = perf_config(pager_command_config, &c);
127 	return err ?: c.val;
128 }
129 
browser_command_config(const char * var,const char * value,void * data)130 static int browser_command_config(const char *var, const char *value, void *data)
131 {
132 	struct pager_config *c = data;
133 	if (same_cmd_with_prefix(var, c, "tui."))
134 		c->val = perf_config_bool(var, value);
135 	if (same_cmd_with_prefix(var, c, "gtk."))
136 		c->val = perf_config_bool(var, value) ? 2 : 0;
137 	return 0;
138 }
139 
140 /*
141  * returns 0 for "no tui", 1 for "use tui", 2 for "use gtk",
142  * and -1 for "not specified"
143  */
check_browser_config(const char * cmd)144 static int check_browser_config(const char *cmd)
145 {
146 	int err;
147 	struct pager_config c;
148 	c.cmd = cmd;
149 	c.val = -1;
150 	err = perf_config(browser_command_config, &c);
151 	return err ?: c.val;
152 }
153 
commit_pager_choice(void)154 static void commit_pager_choice(void)
155 {
156 	switch (use_pager) {
157 	case 0:
158 		setenv(PERF_PAGER_ENVIRONMENT, "cat", 1);
159 		break;
160 	case 1:
161 		/* setup_pager(); */
162 		break;
163 	default:
164 		break;
165 	}
166 }
167 
set_debug_file(const char * path)168 static int set_debug_file(const char *path)
169 {
170 	debug_fp = fopen(path, "w");
171 	if (!debug_fp) {
172 		fprintf(stderr, "Open debug file '%s' failed: %s\n",
173 			path, strerror(errno));
174 		return -1;
175 	}
176 
177 	debug_set_file(debug_fp);
178 	return 0;
179 }
180 
181 struct option options[] = {
182 	OPT_ARGUMENT("help", "help"),
183 	OPT_ARGUMENT("version", "version"),
184 	OPT_ARGUMENT("exec-path", "exec-path"),
185 	OPT_ARGUMENT("html-path", "html-path"),
186 	OPT_ARGUMENT("paginate", "paginate"),
187 	OPT_ARGUMENT("no-pager", "no-pager"),
188 	OPT_ARGUMENT("debugfs-dir", "debugfs-dir"),
189 	OPT_ARGUMENT("buildid-dir", "buildid-dir"),
190 	OPT_ARGUMENT("list-cmds", "list-cmds"),
191 	OPT_ARGUMENT("list-opts", "list-opts"),
192 	OPT_ARGUMENT("debug", "debug"),
193 	OPT_ARGUMENT("debug-file", "debug-file"),
194 	OPT_END()
195 };
196 
handle_options(const char *** argv,int * argc,int * envchanged)197 static int handle_options(const char ***argv, int *argc, int *envchanged)
198 {
199 	int handled = 0;
200 
201 	while (*argc > 0) {
202 		const char *cmd = (*argv)[0];
203 		if (cmd[0] != '-')
204 			break;
205 
206 		/*
207 		 * For legacy reasons, the "version" and "help"
208 		 * commands can be written with "--" prepended
209 		 * to make them look like flags.
210 		 */
211 		if (!strcmp(cmd, "--help") || !strcmp(cmd, "--version"))
212 			break;
213 
214 		/*
215 		 * Shortcut for '-h' and '-v' options to invoke help
216 		 * and version command.
217 		 */
218 		if (!strcmp(cmd, "-h")) {
219 			(*argv)[0] = "--help";
220 			break;
221 		}
222 
223 		if (!strcmp(cmd, "-v")) {
224 			(*argv)[0] = "--version";
225 			break;
226 		}
227 
228 		if (!strcmp(cmd, "-vv")) {
229 			(*argv)[0] = "version";
230 			verbose = 1;
231 			break;
232 		}
233 
234 		/*
235 		 * Check remaining flags.
236 		 */
237 		if (strstarts(cmd, CMD_EXEC_PATH)) {
238 			cmd += strlen(CMD_EXEC_PATH);
239 			if (*cmd == '=')
240 				set_argv_exec_path(cmd + 1);
241 			else {
242 				puts(get_argv_exec_path());
243 				exit(0);
244 			}
245 		} else if (!strcmp(cmd, "--html-path")) {
246 			puts(system_path(PERF_HTML_PATH));
247 			exit(0);
248 		} else if (!strcmp(cmd, "-p") || !strcmp(cmd, "--paginate")) {
249 			use_pager = 1;
250 		} else if (!strcmp(cmd, "--no-pager")) {
251 			use_pager = 0;
252 			if (envchanged)
253 				*envchanged = 1;
254 		} else if (!strcmp(cmd, "--debugfs-dir")) {
255 			if (*argc < 2) {
256 				fprintf(stderr, "No directory given for --debugfs-dir.\n");
257 				usage(perf_usage_string);
258 			}
259 			tracing_path_set((*argv)[1]);
260 			if (envchanged)
261 				*envchanged = 1;
262 			(*argv)++;
263 			(*argc)--;
264 		} else if (!strcmp(cmd, "--buildid-dir")) {
265 			if (*argc < 2) {
266 				fprintf(stderr, "No directory given for --buildid-dir.\n");
267 				usage(perf_usage_string);
268 			}
269 			set_buildid_dir((*argv)[1]);
270 			if (envchanged)
271 				*envchanged = 1;
272 			(*argv)++;
273 			(*argc)--;
274 		} else if (strstarts(cmd, CMD_DEBUGFS_DIR)) {
275 			tracing_path_set(cmd + strlen(CMD_DEBUGFS_DIR));
276 			fprintf(stderr, "dir: %s\n", tracing_path_mount());
277 			if (envchanged)
278 				*envchanged = 1;
279 		} else if (!strcmp(cmd, "--list-cmds")) {
280 			unsigned int i;
281 
282 			for (i = 0; i < ARRAY_SIZE(commands); i++) {
283 				struct cmd_struct *p = commands+i;
284 				printf("%s ", p->cmd);
285 			}
286 			putchar('\n');
287 			exit(0);
288 		} else if (!strcmp(cmd, "--list-opts")) {
289 			unsigned int i;
290 
291 			for (i = 0; i < ARRAY_SIZE(options)-1; i++) {
292 				struct option *p = options+i;
293 				printf("--%s ", p->long_name);
294 			}
295 			putchar('\n');
296 			exit(0);
297 		} else if (!strcmp(cmd, "--debug")) {
298 			if (*argc < 2) {
299 				fprintf(stderr, "No variable specified for --debug.\n");
300 				usage(perf_usage_string);
301 			}
302 			if (perf_debug_option((*argv)[1]))
303 				usage(perf_usage_string);
304 
305 			(*argv)++;
306 			(*argc)--;
307 		} else if (!strcmp(cmd, "--debug-file")) {
308 			if (*argc < 2) {
309 				fprintf(stderr, "No path given for --debug-file.\n");
310 				usage(perf_usage_string);
311 			}
312 
313 			if (set_debug_file((*argv)[1]))
314 				usage(perf_usage_string);
315 
316 			(*argv)++;
317 			(*argc)--;
318 
319 		} else {
320 			fprintf(stderr, "Unknown option: %s\n", cmd);
321 			usage(perf_usage_string);
322 		}
323 
324 		(*argv)++;
325 		(*argc)--;
326 		handled++;
327 	}
328 	return handled;
329 }
330 
331 #define RUN_SETUP	(1<<0)
332 #define USE_PAGER	(1<<1)
333 
run_builtin(struct cmd_struct * p,int argc,const char ** argv)334 static int run_builtin(struct cmd_struct *p, int argc, const char **argv)
335 {
336 	int status;
337 	struct stat st;
338 	char sbuf[STRERR_BUFSIZE];
339 
340 	if (use_browser == -1)
341 		use_browser = check_browser_config(p->cmd);
342 
343 	if (use_pager == -1 && p->option & RUN_SETUP)
344 		use_pager = check_pager_config(p->cmd);
345 	if (use_pager == -1 && p->option & USE_PAGER)
346 		use_pager = 1;
347 	commit_pager_choice();
348 
349 	perf_env__init(&perf_env);
350 	perf_env__set_cmdline(&perf_env, argc, argv);
351 	status = p->fn(argc, argv);
352 	perf_config__exit();
353 	exit_browser(status);
354 	perf_env__exit(&perf_env);
355 
356 	if (status)
357 		return status & 0xff;
358 
359 	/* Somebody closed stdout? */
360 	if (fstat(fileno(stdout), &st))
361 		return 0;
362 	/* Ignore write errors for pipes and sockets.. */
363 	if (S_ISFIFO(st.st_mode) || S_ISSOCK(st.st_mode))
364 		return 0;
365 
366 	status = 1;
367 	/* Check for ENOSPC and EIO errors.. */
368 	if (fflush(stdout)) {
369 		fprintf(stderr, "write failure on standard output: %s",
370 			str_error_r(errno, sbuf, sizeof(sbuf)));
371 		goto out;
372 	}
373 	if (ferror(stdout)) {
374 		fprintf(stderr, "unknown write failure on standard output");
375 		goto out;
376 	}
377 	if (fclose(stdout)) {
378 		fprintf(stderr, "close failed on standard output: %s",
379 			str_error_r(errno, sbuf, sizeof(sbuf)));
380 		goto out;
381 	}
382 	status = 0;
383 out:
384 	return status;
385 }
386 
handle_internal_command(int argc,const char ** argv)387 static void handle_internal_command(int argc, const char **argv)
388 {
389 	const char *cmd = argv[0];
390 	unsigned int i;
391 
392 	/* Turn "perf cmd --help" into "perf help cmd" */
393 	if (argc > 1 && !strcmp(argv[1], "--help")) {
394 		argv[1] = argv[0];
395 		argv[0] = cmd = "help";
396 	}
397 
398 	for (i = 0; i < ARRAY_SIZE(commands); i++) {
399 		struct cmd_struct *p = commands+i;
400 		if (p->fn == NULL)
401 			continue;
402 		if (strcmp(p->cmd, cmd))
403 			continue;
404 		exit(run_builtin(p, argc, argv));
405 	}
406 }
407 
execv_dashed_external(const char ** argv)408 static void execv_dashed_external(const char **argv)
409 {
410 	char *cmd;
411 	const char *tmp;
412 	int status;
413 
414 	if (asprintf(&cmd, "perf-%s", argv[0]) < 0)
415 		goto do_die;
416 
417 	/*
418 	 * argv[0] must be the perf command, but the argv array
419 	 * belongs to the caller, and may be reused in
420 	 * subsequent loop iterations. Save argv[0] and
421 	 * restore it on error.
422 	 */
423 	tmp = argv[0];
424 	argv[0] = cmd;
425 
426 	/*
427 	 * if we fail because the command is not found, it is
428 	 * OK to return. Otherwise, we just pass along the status code.
429 	 */
430 	status = run_command_v_opt(argv, 0);
431 	if (status != -ERR_RUN_COMMAND_EXEC) {
432 		if (IS_RUN_COMMAND_ERR(status)) {
433 do_die:
434 			pr_err("FATAL: unable to run '%s'", argv[0]);
435 			status = -128;
436 		}
437 		exit(-status);
438 	}
439 	errno = ENOENT; /* as if we called execvp */
440 
441 	argv[0] = tmp;
442 	zfree(&cmd);
443 }
444 
run_argv(int * argcp,const char *** argv)445 static int run_argv(int *argcp, const char ***argv)
446 {
447 	/* See if it's an internal command */
448 	handle_internal_command(*argcp, *argv);
449 
450 	/* .. then try the external ones */
451 	execv_dashed_external(*argv);
452 	return 0;
453 }
454 
libperf_print(enum libperf_print_level level,const char * fmt,va_list ap)455 static int libperf_print(enum libperf_print_level level,
456 			 const char *fmt, va_list ap)
457 {
458 	return veprintf(level, verbose, fmt, ap);
459 }
460 
main(int argc,const char ** argv)461 int main(int argc, const char **argv)
462 {
463 	int err, done_help = 0;
464 	const char *cmd;
465 	char sbuf[STRERR_BUFSIZE];
466 
467 	perf_debug_setup();
468 
469 	/* libsubcmd init */
470 	exec_cmd_init("perf", PREFIX, PERF_EXEC_PATH, EXEC_PATH_ENVIRONMENT);
471 	pager_init(PERF_PAGER_ENVIRONMENT);
472 
473 	libperf_init(libperf_print);
474 
475 	cmd = extract_argv0_path(argv[0]);
476 	if (!cmd)
477 		cmd = "perf-help";
478 
479 	srandom(time(NULL));
480 
481 	/* Setting $PERF_CONFIG makes perf read _only_ the given config file. */
482 	config_exclusive_filename = getenv("PERF_CONFIG");
483 
484 	err = perf_config(perf_default_config, NULL);
485 	if (err)
486 		return err;
487 	set_buildid_dir(NULL);
488 
489 	/*
490 	 * "perf-xxxx" is the same as "perf xxxx", but we obviously:
491 	 *
492 	 *  - cannot take flags in between the "perf" and the "xxxx".
493 	 *  - cannot execute it externally (since it would just do
494 	 *    the same thing over again)
495 	 *
496 	 * So we just directly call the internal command handler. If that one
497 	 * fails to handle this, then maybe we just run a renamed perf binary
498 	 * that contains a dash in its name. To handle this scenario, we just
499 	 * fall through and ignore the "xxxx" part of the command string.
500 	 */
501 	if (strstarts(cmd, "perf-")) {
502 		cmd += 5;
503 		argv[0] = cmd;
504 		handle_internal_command(argc, argv);
505 		/*
506 		 * If the command is handled, the above function does not
507 		 * return undo changes and fall through in such a case.
508 		 */
509 		cmd -= 5;
510 		argv[0] = cmd;
511 	}
512 	if (strstarts(cmd, "trace")) {
513 #ifndef HAVE_LIBTRACEEVENT
514 		fprintf(stderr,
515 			"trace command not available: missing libtraceevent devel package at build time.\n");
516 		goto out;
517 #elif !defined(HAVE_LIBAUDIT_SUPPORT) && !defined(HAVE_SYSCALL_TABLE_SUPPORT)
518 		fprintf(stderr,
519 			"trace command not available: missing audit-libs devel package at build time.\n");
520 		goto out;
521 #else
522 		setup_path();
523 		argv[0] = "trace";
524 		return cmd_trace(argc, argv);
525 #endif
526 	}
527 	/* Look for flags.. */
528 	argv++;
529 	argc--;
530 	handle_options(&argv, &argc, NULL);
531 	commit_pager_choice();
532 
533 	if (argc > 0) {
534 		if (strstarts(argv[0], "--"))
535 			argv[0] += 2;
536 	} else {
537 		/* The user didn't specify a command; give them help */
538 		printf("\n usage: %s\n\n", perf_usage_string);
539 		list_common_cmds_help();
540 		printf("\n %s\n\n", perf_more_info_string);
541 		goto out;
542 	}
543 	cmd = argv[0];
544 
545 	test_attr__init();
546 
547 	/*
548 	 * We use PATH to find perf commands, but we prepend some higher
549 	 * precedence paths: the "--exec-path" option, the PERF_EXEC_PATH
550 	 * environment, and the $(perfexecdir) from the Makefile at build
551 	 * time.
552 	 */
553 	setup_path();
554 	/*
555 	 * Block SIGWINCH notifications so that the thread that wants it can
556 	 * unblock and get syscalls like select interrupted instead of waiting
557 	 * forever while the signal goes to some other non interested thread.
558 	 */
559 	pthread__block_sigwinch();
560 
561 	while (1) {
562 		run_argv(&argc, &argv);
563 
564 		if (errno != ENOENT)
565 			break;
566 
567 		if (!done_help) {
568 			struct cmdnames main_cmds = {};
569 
570 			for (unsigned int i = 0; i < ARRAY_SIZE(commands); i++) {
571 				add_cmdname(&main_cmds,
572 					    commands[i].cmd,
573 					    strlen(commands[i].cmd));
574 			}
575 			cmd = argv[0] = help_unknown_cmd(cmd, &main_cmds);
576 			clean_cmdnames(&main_cmds);
577 			done_help = 1;
578 			if (!cmd)
579 				break;
580 		} else
581 			break;
582 	}
583 
584 	if (cmd) {
585 		fprintf(stderr, "Failed to run command '%s': %s\n",
586 			cmd, str_error_r(errno, sbuf, sizeof(sbuf)));
587 	}
588 out:
589 	if (debug_fp)
590 		fclose(debug_fp);
591 
592 	return 1;
593 }
594