xref: /linux/tools/perf/perf.c (revision 2da68a77) 
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 	{ "kwork",	cmd_kwork,	0 },
95 };
96 
97 struct pager_config {
98 	const char *cmd;
99 	int val;
100 };
101 
102 static bool same_cmd_with_prefix(const char *var, struct pager_config *c,
103 				  const char *header)
104 {
105 	return (strstarts(var, header) && !strcmp(var + strlen(header), c->cmd));
106 }
107 
108 static int pager_command_config(const char *var, const char *value, void *data)
109 {
110 	struct pager_config *c = data;
111 	if (same_cmd_with_prefix(var, c, "pager."))
112 		c->val = perf_config_bool(var, value);
113 	return 0;
114 }
115 
116 /* returns 0 for "no pager", 1 for "use pager", and -1 for "not specified" */
117 static int check_pager_config(const char *cmd)
118 {
119 	int err;
120 	struct pager_config c;
121 	c.cmd = cmd;
122 	c.val = -1;
123 	err = perf_config(pager_command_config, &c);
124 	return err ?: c.val;
125 }
126 
127 static int browser_command_config(const char *var, const char *value, void *data)
128 {
129 	struct pager_config *c = data;
130 	if (same_cmd_with_prefix(var, c, "tui."))
131 		c->val = perf_config_bool(var, value);
132 	if (same_cmd_with_prefix(var, c, "gtk."))
133 		c->val = perf_config_bool(var, value) ? 2 : 0;
134 	return 0;
135 }
136 
137 /*
138  * returns 0 for "no tui", 1 for "use tui", 2 for "use gtk",
139  * and -1 for "not specified"
140  */
141 static int check_browser_config(const char *cmd)
142 {
143 	int err;
144 	struct pager_config c;
145 	c.cmd = cmd;
146 	c.val = -1;
147 	err = perf_config(browser_command_config, &c);
148 	return err ?: c.val;
149 }
150 
151 static void commit_pager_choice(void)
152 {
153 	switch (use_pager) {
154 	case 0:
155 		setenv(PERF_PAGER_ENVIRONMENT, "cat", 1);
156 		break;
157 	case 1:
158 		/* setup_pager(); */
159 		break;
160 	default:
161 		break;
162 	}
163 }
164 
165 struct option options[] = {
166 	OPT_ARGUMENT("help", "help"),
167 	OPT_ARGUMENT("version", "version"),
168 	OPT_ARGUMENT("exec-path", "exec-path"),
169 	OPT_ARGUMENT("html-path", "html-path"),
170 	OPT_ARGUMENT("paginate", "paginate"),
171 	OPT_ARGUMENT("no-pager", "no-pager"),
172 	OPT_ARGUMENT("debugfs-dir", "debugfs-dir"),
173 	OPT_ARGUMENT("buildid-dir", "buildid-dir"),
174 	OPT_ARGUMENT("list-cmds", "list-cmds"),
175 	OPT_ARGUMENT("list-opts", "list-opts"),
176 	OPT_ARGUMENT("debug", "debug"),
177 	OPT_END()
178 };
179 
180 static int handle_options(const char ***argv, int *argc, int *envchanged)
181 {
182 	int handled = 0;
183 
184 	while (*argc > 0) {
185 		const char *cmd = (*argv)[0];
186 		if (cmd[0] != '-')
187 			break;
188 
189 		/*
190 		 * For legacy reasons, the "version" and "help"
191 		 * commands can be written with "--" prepended
192 		 * to make them look like flags.
193 		 */
194 		if (!strcmp(cmd, "--help") || !strcmp(cmd, "--version"))
195 			break;
196 
197 		/*
198 		 * Shortcut for '-h' and '-v' options to invoke help
199 		 * and version command.
200 		 */
201 		if (!strcmp(cmd, "-h")) {
202 			(*argv)[0] = "--help";
203 			break;
204 		}
205 
206 		if (!strcmp(cmd, "-v")) {
207 			(*argv)[0] = "--version";
208 			break;
209 		}
210 
211 		if (!strcmp(cmd, "-vv")) {
212 			(*argv)[0] = "version";
213 			version_verbose = 1;
214 			break;
215 		}
216 
217 		/*
218 		 * Check remaining flags.
219 		 */
220 		if (strstarts(cmd, CMD_EXEC_PATH)) {
221 			cmd += strlen(CMD_EXEC_PATH);
222 			if (*cmd == '=')
223 				set_argv_exec_path(cmd + 1);
224 			else {
225 				puts(get_argv_exec_path());
226 				exit(0);
227 			}
228 		} else if (!strcmp(cmd, "--html-path")) {
229 			puts(system_path(PERF_HTML_PATH));
230 			exit(0);
231 		} else if (!strcmp(cmd, "-p") || !strcmp(cmd, "--paginate")) {
232 			use_pager = 1;
233 		} else if (!strcmp(cmd, "--no-pager")) {
234 			use_pager = 0;
235 			if (envchanged)
236 				*envchanged = 1;
237 		} else if (!strcmp(cmd, "--debugfs-dir")) {
238 			if (*argc < 2) {
239 				fprintf(stderr, "No directory given for --debugfs-dir.\n");
240 				usage(perf_usage_string);
241 			}
242 			tracing_path_set((*argv)[1]);
243 			if (envchanged)
244 				*envchanged = 1;
245 			(*argv)++;
246 			(*argc)--;
247 		} else if (!strcmp(cmd, "--buildid-dir")) {
248 			if (*argc < 2) {
249 				fprintf(stderr, "No directory given for --buildid-dir.\n");
250 				usage(perf_usage_string);
251 			}
252 			set_buildid_dir((*argv)[1]);
253 			if (envchanged)
254 				*envchanged = 1;
255 			(*argv)++;
256 			(*argc)--;
257 		} else if (strstarts(cmd, CMD_DEBUGFS_DIR)) {
258 			tracing_path_set(cmd + strlen(CMD_DEBUGFS_DIR));
259 			fprintf(stderr, "dir: %s\n", tracing_path_mount());
260 			if (envchanged)
261 				*envchanged = 1;
262 		} else if (!strcmp(cmd, "--list-cmds")) {
263 			unsigned int i;
264 
265 			for (i = 0; i < ARRAY_SIZE(commands); i++) {
266 				struct cmd_struct *p = commands+i;
267 				printf("%s ", p->cmd);
268 			}
269 			putchar('\n');
270 			exit(0);
271 		} else if (!strcmp(cmd, "--list-opts")) {
272 			unsigned int i;
273 
274 			for (i = 0; i < ARRAY_SIZE(options)-1; i++) {
275 				struct option *p = options+i;
276 				printf("--%s ", p->long_name);
277 			}
278 			putchar('\n');
279 			exit(0);
280 		} else if (!strcmp(cmd, "--debug")) {
281 			if (*argc < 2) {
282 				fprintf(stderr, "No variable specified for --debug.\n");
283 				usage(perf_usage_string);
284 			}
285 			if (perf_debug_option((*argv)[1]))
286 				usage(perf_usage_string);
287 
288 			(*argv)++;
289 			(*argc)--;
290 		} else {
291 			fprintf(stderr, "Unknown option: %s\n", cmd);
292 			usage(perf_usage_string);
293 		}
294 
295 		(*argv)++;
296 		(*argc)--;
297 		handled++;
298 	}
299 	return handled;
300 }
301 
302 #define RUN_SETUP	(1<<0)
303 #define USE_PAGER	(1<<1)
304 
305 static int run_builtin(struct cmd_struct *p, int argc, const char **argv)
306 {
307 	int status;
308 	struct stat st;
309 	char sbuf[STRERR_BUFSIZE];
310 
311 	if (use_browser == -1)
312 		use_browser = check_browser_config(p->cmd);
313 
314 	if (use_pager == -1 && p->option & RUN_SETUP)
315 		use_pager = check_pager_config(p->cmd);
316 	if (use_pager == -1 && p->option & USE_PAGER)
317 		use_pager = 1;
318 	commit_pager_choice();
319 
320 	perf_env__init(&perf_env);
321 	perf_env__set_cmdline(&perf_env, argc, argv);
322 	status = p->fn(argc, argv);
323 	perf_config__exit();
324 	exit_browser(status);
325 	perf_env__exit(&perf_env);
326 	bpf__clear();
327 
328 	if (status)
329 		return status & 0xff;
330 
331 	/* Somebody closed stdout? */
332 	if (fstat(fileno(stdout), &st))
333 		return 0;
334 	/* Ignore write errors for pipes and sockets.. */
335 	if (S_ISFIFO(st.st_mode) || S_ISSOCK(st.st_mode))
336 		return 0;
337 
338 	status = 1;
339 	/* Check for ENOSPC and EIO errors.. */
340 	if (fflush(stdout)) {
341 		fprintf(stderr, "write failure on standard output: %s",
342 			str_error_r(errno, sbuf, sizeof(sbuf)));
343 		goto out;
344 	}
345 	if (ferror(stdout)) {
346 		fprintf(stderr, "unknown write failure on standard output");
347 		goto out;
348 	}
349 	if (fclose(stdout)) {
350 		fprintf(stderr, "close failed on standard output: %s",
351 			str_error_r(errno, sbuf, sizeof(sbuf)));
352 		goto out;
353 	}
354 	status = 0;
355 out:
356 	return status;
357 }
358 
359 static void handle_internal_command(int argc, const char **argv)
360 {
361 	const char *cmd = argv[0];
362 	unsigned int i;
363 
364 	/* Turn "perf cmd --help" into "perf help cmd" */
365 	if (argc > 1 && !strcmp(argv[1], "--help")) {
366 		argv[1] = argv[0];
367 		argv[0] = cmd = "help";
368 	}
369 
370 	for (i = 0; i < ARRAY_SIZE(commands); i++) {
371 		struct cmd_struct *p = commands+i;
372 		if (p->fn == NULL)
373 			continue;
374 		if (strcmp(p->cmd, cmd))
375 			continue;
376 		exit(run_builtin(p, argc, argv));
377 	}
378 }
379 
380 static void execv_dashed_external(const char **argv)
381 {
382 	char *cmd;
383 	const char *tmp;
384 	int status;
385 
386 	if (asprintf(&cmd, "perf-%s", argv[0]) < 0)
387 		goto do_die;
388 
389 	/*
390 	 * argv[0] must be the perf command, but the argv array
391 	 * belongs to the caller, and may be reused in
392 	 * subsequent loop iterations. Save argv[0] and
393 	 * restore it on error.
394 	 */
395 	tmp = argv[0];
396 	argv[0] = cmd;
397 
398 	/*
399 	 * if we fail because the command is not found, it is
400 	 * OK to return. Otherwise, we just pass along the status code.
401 	 */
402 	status = run_command_v_opt(argv, 0);
403 	if (status != -ERR_RUN_COMMAND_EXEC) {
404 		if (IS_RUN_COMMAND_ERR(status)) {
405 do_die:
406 			pr_err("FATAL: unable to run '%s'", argv[0]);
407 			status = -128;
408 		}
409 		exit(-status);
410 	}
411 	errno = ENOENT; /* as if we called execvp */
412 
413 	argv[0] = tmp;
414 	zfree(&cmd);
415 }
416 
417 static int run_argv(int *argcp, const char ***argv)
418 {
419 	/* See if it's an internal command */
420 	handle_internal_command(*argcp, *argv);
421 
422 	/* .. then try the external ones */
423 	execv_dashed_external(*argv);
424 	return 0;
425 }
426 
427 static void pthread__block_sigwinch(void)
428 {
429 	sigset_t set;
430 
431 	sigemptyset(&set);
432 	sigaddset(&set, SIGWINCH);
433 	pthread_sigmask(SIG_BLOCK, &set, NULL);
434 }
435 
436 void pthread__unblock_sigwinch(void)
437 {
438 	sigset_t set;
439 
440 	sigemptyset(&set);
441 	sigaddset(&set, SIGWINCH);
442 	pthread_sigmask(SIG_UNBLOCK, &set, NULL);
443 }
444 
445 static int libperf_print(enum libperf_print_level level,
446 			 const char *fmt, va_list ap)
447 {
448 	return veprintf(level, verbose, fmt, ap);
449 }
450 
451 int main(int argc, const char **argv)
452 {
453 	int err;
454 	const char *cmd;
455 	char sbuf[STRERR_BUFSIZE];
456 
457 	perf_debug_setup();
458 
459 	/* libsubcmd init */
460 	exec_cmd_init("perf", PREFIX, PERF_EXEC_PATH, EXEC_PATH_ENVIRONMENT);
461 	pager_init(PERF_PAGER_ENVIRONMENT);
462 
463 	libperf_init(libperf_print);
464 
465 	cmd = extract_argv0_path(argv[0]);
466 	if (!cmd)
467 		cmd = "perf-help";
468 
469 	srandom(time(NULL));
470 
471 	/* Setting $PERF_CONFIG makes perf read _only_ the given config file. */
472 	config_exclusive_filename = getenv("PERF_CONFIG");
473 
474 	err = perf_config(perf_default_config, NULL);
475 	if (err)
476 		return err;
477 	set_buildid_dir(NULL);
478 
479 	/*
480 	 * "perf-xxxx" is the same as "perf xxxx", but we obviously:
481 	 *
482 	 *  - cannot take flags in between the "perf" and the "xxxx".
483 	 *  - cannot execute it externally (since it would just do
484 	 *    the same thing over again)
485 	 *
486 	 * So we just directly call the internal command handler. If that one
487 	 * fails to handle this, then maybe we just run a renamed perf binary
488 	 * that contains a dash in its name. To handle this scenario, we just
489 	 * fall through and ignore the "xxxx" part of the command string.
490 	 */
491 	if (strstarts(cmd, "perf-")) {
492 		cmd += 5;
493 		argv[0] = cmd;
494 		handle_internal_command(argc, argv);
495 		/*
496 		 * If the command is handled, the above function does not
497 		 * return undo changes and fall through in such a case.
498 		 */
499 		cmd -= 5;
500 		argv[0] = cmd;
501 	}
502 	if (strstarts(cmd, "trace")) {
503 #if defined(HAVE_LIBAUDIT_SUPPORT) || defined(HAVE_SYSCALL_TABLE_SUPPORT)
504 		setup_path();
505 		argv[0] = "trace";
506 		return cmd_trace(argc, argv);
507 #else
508 		fprintf(stderr,
509 			"trace command not available: missing audit-libs devel package at build time.\n");
510 		goto out;
511 #endif
512 	}
513 	/* Look for flags.. */
514 	argv++;
515 	argc--;
516 	handle_options(&argv, &argc, NULL);
517 	commit_pager_choice();
518 
519 	if (argc > 0) {
520 		if (strstarts(argv[0], "--"))
521 			argv[0] += 2;
522 	} else {
523 		/* The user didn't specify a command; give them help */
524 		printf("\n usage: %s\n\n", perf_usage_string);
525 		list_common_cmds_help();
526 		printf("\n %s\n\n", perf_more_info_string);
527 		goto out;
528 	}
529 	cmd = argv[0];
530 
531 	test_attr__init();
532 
533 	/*
534 	 * We use PATH to find perf commands, but we prepend some higher
535 	 * precedence paths: the "--exec-path" option, the PERF_EXEC_PATH
536 	 * environment, and the $(perfexecdir) from the Makefile at build
537 	 * time.
538 	 */
539 	setup_path();
540 	/*
541 	 * Block SIGWINCH notifications so that the thread that wants it can
542 	 * unblock and get syscalls like select interrupted instead of waiting
543 	 * forever while the signal goes to some other non interested thread.
544 	 */
545 	pthread__block_sigwinch();
546 
547 	while (1) {
548 		static int done_help;
549 
550 		run_argv(&argc, &argv);
551 
552 		if (errno != ENOENT)
553 			break;
554 
555 		if (!done_help) {
556 			cmd = argv[0] = help_unknown_cmd(cmd);
557 			done_help = 1;
558 		} else
559 			break;
560 	}
561 
562 	fprintf(stderr, "Failed to run command '%s': %s\n",
563 		cmd, str_error_r(errno, sbuf, sizeof(sbuf)));
564 out:
565 	return 1;
566 }
567