xref: /linux/tools/perf/perf.c (revision fa0d98462fae5d4951f22f3ac1090d48c53396d1) 
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 <subcmd/exec-cmd.h>
16 #include "util/config.h"
17 #include <subcmd/run-command.h>
18 #include "util/parse-events.h"
19 #include <subcmd/parse-options.h>
20 #include "util/bpf-loader.h"
21 #include "util/debug.h"
22 #include "util/event.h"
23 #include "util/util.h"
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 <errno.h>
29 #include <pthread.h>
30 #include <signal.h>
31 #include <stdlib.h>
32 #include <time.h>
33 #include <sys/types.h>
34 #include <sys/stat.h>
35 #include <unistd.h>
36 #include <linux/kernel.h>
37 #include <linux/string.h>
38 #include <linux/zalloc.h>
39 
40 const char perf_usage_string[] =
41 	"perf [--version] [--help] [OPTIONS] COMMAND [ARGS]";
42 
43 const char perf_more_info_string[] =
44 	"See 'perf help COMMAND' for more information on a specific command.";
45 
46 static int use_pager = -1;
47 const char *input_name;
48 
49 struct cmd_struct {
50 	const char *cmd;
51 	int (*fn)(int, const char **);
52 	int option;
53 };
54 
55 static struct cmd_struct commands[] = {
56 	{ "buildid-cache", cmd_buildid_cache, 0 },
57 	{ "buildid-list", cmd_buildid_list, 0 },
58 	{ "config",	cmd_config,	0 },
59 	{ "c2c",	cmd_c2c,	0 },
60 	{ "diff",	cmd_diff,	0 },
61 	{ "evlist",	cmd_evlist,	0 },
62 	{ "help",	cmd_help,	0 },
63 	{ "kallsyms",	cmd_kallsyms,	0 },
64 	{ "list",	cmd_list,	0 },
65 	{ "record",	cmd_record,	0 },
66 	{ "report",	cmd_report,	0 },
67 	{ "bench",	cmd_bench,	0 },
68 	{ "stat",	cmd_stat,	0 },
69 	{ "timechart",	cmd_timechart,	0 },
70 	{ "top",	cmd_top,	0 },
71 	{ "annotate",	cmd_annotate,	0 },
72 	{ "version",	cmd_version,	0 },
73 	{ "script",	cmd_script,	0 },
74 	{ "sched",	cmd_sched,	0 },
75 #ifdef HAVE_LIBELF_SUPPORT
76 	{ "probe",	cmd_probe,	0 },
77 #endif
78 	{ "kmem",	cmd_kmem,	0 },
79 	{ "lock",	cmd_lock,	0 },
80 	{ "kvm",	cmd_kvm,	0 },
81 	{ "test",	cmd_test,	0 },
82 #if defined(HAVE_LIBAUDIT_SUPPORT) || defined(HAVE_SYSCALL_TABLE_SUPPORT)
83 	{ "trace",	cmd_trace,	0 },
84 #endif
85 	{ "inject",	cmd_inject,	0 },
86 	{ "mem",	cmd_mem,	0 },
87 	{ "data",	cmd_data,	0 },
88 	{ "ftrace",	cmd_ftrace,	0 },
89 };
90 
91 struct pager_config {
92 	const char *cmd;
93 	int val;
94 };
95 
96 static int pager_command_config(const char *var, const char *value, void *data)
97 {
98 	struct pager_config *c = data;
99 	if (strstarts(var, "pager.") && !strcmp(var + 6, c->cmd))
100 		c->val = perf_config_bool(var, value);
101 	return 0;
102 }
103 
104 /* returns 0 for "no pager", 1 for "use pager", and -1 for "not specified" */
105 static int check_pager_config(const char *cmd)
106 {
107 	int err;
108 	struct pager_config c;
109 	c.cmd = cmd;
110 	c.val = -1;
111 	err = perf_config(pager_command_config, &c);
112 	return err ?: c.val;
113 }
114 
115 static int browser_command_config(const char *var, const char *value, void *data)
116 {
117 	struct pager_config *c = data;
118 	if (strstarts(var, "tui.") && !strcmp(var + 4, c->cmd))
119 		c->val = perf_config_bool(var, value);
120 	if (strstarts(var, "gtk.") && !strcmp(var + 4, c->cmd))
121 		c->val = perf_config_bool(var, value) ? 2 : 0;
122 	return 0;
123 }
124 
125 /*
126  * returns 0 for "no tui", 1 for "use tui", 2 for "use gtk",
127  * and -1 for "not specified"
128  */
129 static int check_browser_config(const char *cmd)
130 {
131 	int err;
132 	struct pager_config c;
133 	c.cmd = cmd;
134 	c.val = -1;
135 	err = perf_config(browser_command_config, &c);
136 	return err ?: c.val;
137 }
138 
139 static void commit_pager_choice(void)
140 {
141 	switch (use_pager) {
142 	case 0:
143 		setenv(PERF_PAGER_ENVIRONMENT, "cat", 1);
144 		break;
145 	case 1:
146 		/* setup_pager(); */
147 		break;
148 	default:
149 		break;
150 	}
151 }
152 
153 struct option options[] = {
154 	OPT_ARGUMENT("help", "help"),
155 	OPT_ARGUMENT("version", "version"),
156 	OPT_ARGUMENT("exec-path", "exec-path"),
157 	OPT_ARGUMENT("html-path", "html-path"),
158 	OPT_ARGUMENT("paginate", "paginate"),
159 	OPT_ARGUMENT("no-pager", "no-pager"),
160 	OPT_ARGUMENT("debugfs-dir", "debugfs-dir"),
161 	OPT_ARGUMENT("buildid-dir", "buildid-dir"),
162 	OPT_ARGUMENT("list-cmds", "list-cmds"),
163 	OPT_ARGUMENT("list-opts", "list-opts"),
164 	OPT_ARGUMENT("debug", "debug"),
165 	OPT_END()
166 };
167 
168 static int handle_options(const char ***argv, int *argc, int *envchanged)
169 {
170 	int handled = 0;
171 
172 	while (*argc > 0) {
173 		const char *cmd = (*argv)[0];
174 		if (cmd[0] != '-')
175 			break;
176 
177 		/*
178 		 * For legacy reasons, the "version" and "help"
179 		 * commands can be written with "--" prepended
180 		 * to make them look like flags.
181 		 */
182 		if (!strcmp(cmd, "--help") || !strcmp(cmd, "--version"))
183 			break;
184 
185 		/*
186 		 * Shortcut for '-h' and '-v' options to invoke help
187 		 * and version command.
188 		 */
189 		if (!strcmp(cmd, "-h")) {
190 			(*argv)[0] = "--help";
191 			break;
192 		}
193 
194 		if (!strcmp(cmd, "-v")) {
195 			(*argv)[0] = "--version";
196 			break;
197 		}
198 
199 		if (!strcmp(cmd, "-vv")) {
200 			(*argv)[0] = "version";
201 			version_verbose = 1;
202 			break;
203 		}
204 
205 		/*
206 		 * Check remaining flags.
207 		 */
208 		if (strstarts(cmd, CMD_EXEC_PATH)) {
209 			cmd += strlen(CMD_EXEC_PATH);
210 			if (*cmd == '=')
211 				set_argv_exec_path(cmd + 1);
212 			else {
213 				puts(get_argv_exec_path());
214 				exit(0);
215 			}
216 		} else if (!strcmp(cmd, "--html-path")) {
217 			puts(system_path(PERF_HTML_PATH));
218 			exit(0);
219 		} else if (!strcmp(cmd, "-p") || !strcmp(cmd, "--paginate")) {
220 			use_pager = 1;
221 		} else if (!strcmp(cmd, "--no-pager")) {
222 			use_pager = 0;
223 			if (envchanged)
224 				*envchanged = 1;
225 		} else if (!strcmp(cmd, "--debugfs-dir")) {
226 			if (*argc < 2) {
227 				fprintf(stderr, "No directory given for --debugfs-dir.\n");
228 				usage(perf_usage_string);
229 			}
230 			tracing_path_set((*argv)[1]);
231 			if (envchanged)
232 				*envchanged = 1;
233 			(*argv)++;
234 			(*argc)--;
235 		} else if (!strcmp(cmd, "--buildid-dir")) {
236 			if (*argc < 2) {
237 				fprintf(stderr, "No directory given for --buildid-dir.\n");
238 				usage(perf_usage_string);
239 			}
240 			set_buildid_dir((*argv)[1]);
241 			if (envchanged)
242 				*envchanged = 1;
243 			(*argv)++;
244 			(*argc)--;
245 		} else if (strstarts(cmd, CMD_DEBUGFS_DIR)) {
246 			tracing_path_set(cmd + strlen(CMD_DEBUGFS_DIR));
247 			fprintf(stderr, "dir: %s\n", tracing_path_mount());
248 			if (envchanged)
249 				*envchanged = 1;
250 		} else if (!strcmp(cmd, "--list-cmds")) {
251 			unsigned int i;
252 
253 			for (i = 0; i < ARRAY_SIZE(commands); i++) {
254 				struct cmd_struct *p = commands+i;
255 				printf("%s ", p->cmd);
256 			}
257 			putchar('\n');
258 			exit(0);
259 		} else if (!strcmp(cmd, "--list-opts")) {
260 			unsigned int i;
261 
262 			for (i = 0; i < ARRAY_SIZE(options)-1; i++) {
263 				struct option *p = options+i;
264 				printf("--%s ", p->long_name);
265 			}
266 			putchar('\n');
267 			exit(0);
268 		} else if (!strcmp(cmd, "--debug")) {
269 			if (*argc < 2) {
270 				fprintf(stderr, "No variable specified for --debug.\n");
271 				usage(perf_usage_string);
272 			}
273 			if (perf_debug_option((*argv)[1]))
274 				usage(perf_usage_string);
275 
276 			(*argv)++;
277 			(*argc)--;
278 		} else {
279 			fprintf(stderr, "Unknown option: %s\n", cmd);
280 			usage(perf_usage_string);
281 		}
282 
283 		(*argv)++;
284 		(*argc)--;
285 		handled++;
286 	}
287 	return handled;
288 }
289 
290 #define RUN_SETUP	(1<<0)
291 #define USE_PAGER	(1<<1)
292 
293 static int run_builtin(struct cmd_struct *p, int argc, const char **argv)
294 {
295 	int status;
296 	struct stat st;
297 	char sbuf[STRERR_BUFSIZE];
298 
299 	if (use_browser == -1)
300 		use_browser = check_browser_config(p->cmd);
301 
302 	if (use_pager == -1 && p->option & RUN_SETUP)
303 		use_pager = check_pager_config(p->cmd);
304 	if (use_pager == -1 && p->option & USE_PAGER)
305 		use_pager = 1;
306 	commit_pager_choice();
307 
308 	perf_env__init(&perf_env);
309 	perf_env__set_cmdline(&perf_env, argc, argv);
310 	status = p->fn(argc, argv);
311 	perf_config__exit();
312 	exit_browser(status);
313 	perf_env__exit(&perf_env);
314 	bpf__clear();
315 
316 	if (status)
317 		return status & 0xff;
318 
319 	/* Somebody closed stdout? */
320 	if (fstat(fileno(stdout), &st))
321 		return 0;
322 	/* Ignore write errors for pipes and sockets.. */
323 	if (S_ISFIFO(st.st_mode) || S_ISSOCK(st.st_mode))
324 		return 0;
325 
326 	status = 1;
327 	/* Check for ENOSPC and EIO errors.. */
328 	if (fflush(stdout)) {
329 		fprintf(stderr, "write failure on standard output: %s",
330 			str_error_r(errno, sbuf, sizeof(sbuf)));
331 		goto out;
332 	}
333 	if (ferror(stdout)) {
334 		fprintf(stderr, "unknown write failure on standard output");
335 		goto out;
336 	}
337 	if (fclose(stdout)) {
338 		fprintf(stderr, "close failed on standard output: %s",
339 			str_error_r(errno, sbuf, sizeof(sbuf)));
340 		goto out;
341 	}
342 	status = 0;
343 out:
344 	return status;
345 }
346 
347 static void handle_internal_command(int argc, const char **argv)
348 {
349 	const char *cmd = argv[0];
350 	unsigned int i;
351 
352 	/* Turn "perf cmd --help" into "perf help cmd" */
353 	if (argc > 1 && !strcmp(argv[1], "--help")) {
354 		argv[1] = argv[0];
355 		argv[0] = cmd = "help";
356 	}
357 
358 	for (i = 0; i < ARRAY_SIZE(commands); i++) {
359 		struct cmd_struct *p = commands+i;
360 		if (strcmp(p->cmd, cmd))
361 			continue;
362 		exit(run_builtin(p, argc, argv));
363 	}
364 }
365 
366 static void execv_dashed_external(const char **argv)
367 {
368 	char *cmd;
369 	const char *tmp;
370 	int status;
371 
372 	if (asprintf(&cmd, "perf-%s", argv[0]) < 0)
373 		goto do_die;
374 
375 	/*
376 	 * argv[0] must be the perf command, but the argv array
377 	 * belongs to the caller, and may be reused in
378 	 * subsequent loop iterations. Save argv[0] and
379 	 * restore it on error.
380 	 */
381 	tmp = argv[0];
382 	argv[0] = cmd;
383 
384 	/*
385 	 * if we fail because the command is not found, it is
386 	 * OK to return. Otherwise, we just pass along the status code.
387 	 */
388 	status = run_command_v_opt(argv, 0);
389 	if (status != -ERR_RUN_COMMAND_EXEC) {
390 		if (IS_RUN_COMMAND_ERR(status)) {
391 do_die:
392 			pr_err("FATAL: unable to run '%s'", argv[0]);
393 			status = -128;
394 		}
395 		exit(-status);
396 	}
397 	errno = ENOENT; /* as if we called execvp */
398 
399 	argv[0] = tmp;
400 	zfree(&cmd);
401 }
402 
403 static int run_argv(int *argcp, const char ***argv)
404 {
405 	/* See if it's an internal command */
406 	handle_internal_command(*argcp, *argv);
407 
408 	/* .. then try the external ones */
409 	execv_dashed_external(*argv);
410 	return 0;
411 }
412 
413 static void pthread__block_sigwinch(void)
414 {
415 	sigset_t set;
416 
417 	sigemptyset(&set);
418 	sigaddset(&set, SIGWINCH);
419 	pthread_sigmask(SIG_BLOCK, &set, NULL);
420 }
421 
422 void pthread__unblock_sigwinch(void)
423 {
424 	sigset_t set;
425 
426 	sigemptyset(&set);
427 	sigaddset(&set, SIGWINCH);
428 	pthread_sigmask(SIG_UNBLOCK, &set, NULL);
429 }
430 
431 int main(int argc, const char **argv)
432 {
433 	int err;
434 	const char *cmd;
435 	char sbuf[STRERR_BUFSIZE];
436 
437 	/* libsubcmd init */
438 	exec_cmd_init("perf", PREFIX, PERF_EXEC_PATH, EXEC_PATH_ENVIRONMENT);
439 	pager_init(PERF_PAGER_ENVIRONMENT);
440 
441 	/* The page_size is placed in util object. */
442 	page_size = sysconf(_SC_PAGE_SIZE);
443 
444 	cmd = extract_argv0_path(argv[0]);
445 	if (!cmd)
446 		cmd = "perf-help";
447 
448 	srandom(time(NULL));
449 
450 	/* Setting $PERF_CONFIG makes perf read _only_ the given config file. */
451 	config_exclusive_filename = getenv("PERF_CONFIG");
452 
453 	err = perf_config(perf_default_config, NULL);
454 	if (err)
455 		return err;
456 	set_buildid_dir(NULL);
457 
458 	/*
459 	 * "perf-xxxx" is the same as "perf xxxx", but we obviously:
460 	 *
461 	 *  - cannot take flags in between the "perf" and the "xxxx".
462 	 *  - cannot execute it externally (since it would just do
463 	 *    the same thing over again)
464 	 *
465 	 * So we just directly call the internal command handler. If that one
466 	 * fails to handle this, then maybe we just run a renamed perf binary
467 	 * that contains a dash in its name. To handle this scenario, we just
468 	 * fall through and ignore the "xxxx" part of the command string.
469 	 */
470 	if (strstarts(cmd, "perf-")) {
471 		cmd += 5;
472 		argv[0] = cmd;
473 		handle_internal_command(argc, argv);
474 		/*
475 		 * If the command is handled, the above function does not
476 		 * return undo changes and fall through in such a case.
477 		 */
478 		cmd -= 5;
479 		argv[0] = cmd;
480 	}
481 	if (strstarts(cmd, "trace")) {
482 #if defined(HAVE_LIBAUDIT_SUPPORT) || defined(HAVE_SYSCALL_TABLE_SUPPORT)
483 		setup_path();
484 		argv[0] = "trace";
485 		return cmd_trace(argc, argv);
486 #else
487 		fprintf(stderr,
488 			"trace command not available: missing audit-libs devel package at build time.\n");
489 		goto out;
490 #endif
491 	}
492 	/* Look for flags.. */
493 	argv++;
494 	argc--;
495 	handle_options(&argv, &argc, NULL);
496 	commit_pager_choice();
497 
498 	if (argc > 0) {
499 		if (strstarts(argv[0], "--"))
500 			argv[0] += 2;
501 	} else {
502 		/* The user didn't specify a command; give them help */
503 		printf("\n usage: %s\n\n", perf_usage_string);
504 		list_common_cmds_help();
505 		printf("\n %s\n\n", perf_more_info_string);
506 		goto out;
507 	}
508 	cmd = argv[0];
509 
510 	test_attr__init();
511 
512 	/*
513 	 * We use PATH to find perf commands, but we prepend some higher
514 	 * precedence paths: the "--exec-path" option, the PERF_EXEC_PATH
515 	 * environment, and the $(perfexecdir) from the Makefile at build
516 	 * time.
517 	 */
518 	setup_path();
519 	/*
520 	 * Block SIGWINCH notifications so that the thread that wants it can
521 	 * unblock and get syscalls like select interrupted instead of waiting
522 	 * forever while the signal goes to some other non interested thread.
523 	 */
524 	pthread__block_sigwinch();
525 
526 	perf_debug_setup();
527 
528 	while (1) {
529 		static int done_help;
530 
531 		run_argv(&argc, &argv);
532 
533 		if (errno != ENOENT)
534 			break;
535 
536 		if (!done_help) {
537 			cmd = argv[0] = help_unknown_cmd(cmd);
538 			done_help = 1;
539 		} else
540 			break;
541 	}
542 
543 	fprintf(stderr, "Failed to run command '%s': %s\n",
544 		cmd, str_error_r(errno, sbuf, sizeof(sbuf)));
545 out:
546 	return 1;
547 }
548