xref: /openbmc/linux/tools/perf/perf.c (revision d47a97bd) 
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 #ifdef HAVE_LIBTRACEEVENT
74 	{ "timechart",	cmd_timechart,	0 },
75 #endif
76 	{ "top",	cmd_top,	0 },
77 	{ "annotate",	cmd_annotate,	0 },
78 	{ "version",	cmd_version,	0 },
79 	{ "script",	cmd_script,	0 },
80 #ifdef HAVE_LIBTRACEEVENT
81 	{ "sched",	cmd_sched,	0 },
82 #endif
83 #ifdef HAVE_LIBELF_SUPPORT
84 	{ "probe",	cmd_probe,	0 },
85 #endif
86 #ifdef HAVE_LIBTRACEEVENT
87 	{ "kmem",	cmd_kmem,	0 },
88 	{ "lock",	cmd_lock,	0 },
89 #endif
90 	{ "kvm",	cmd_kvm,	0 },
91 	{ "test",	cmd_test,	0 },
92 #if defined(HAVE_LIBTRACEEVENT) && (defined(HAVE_LIBAUDIT_SUPPORT) || defined(HAVE_SYSCALL_TABLE_SUPPORT))
93 	{ "trace",	cmd_trace,	0 },
94 #endif
95 	{ "inject",	cmd_inject,	0 },
96 	{ "mem",	cmd_mem,	0 },
97 	{ "data",	cmd_data,	0 },
98 	{ "ftrace",	cmd_ftrace,	0 },
99 	{ "daemon",	cmd_daemon,	0 },
100 #ifdef HAVE_LIBTRACEEVENT
101 	{ "kwork",	cmd_kwork,	0 },
102 #endif
103 };
104 
105 struct pager_config {
106 	const char *cmd;
107 	int val;
108 };
109 
110 static bool same_cmd_with_prefix(const char *var, struct pager_config *c,
111 				  const char *header)
112 {
113 	return (strstarts(var, header) && !strcmp(var + strlen(header), c->cmd));
114 }
115 
116 static int pager_command_config(const char *var, const char *value, void *data)
117 {
118 	struct pager_config *c = data;
119 	if (same_cmd_with_prefix(var, c, "pager."))
120 		c->val = perf_config_bool(var, value);
121 	return 0;
122 }
123 
124 /* returns 0 for "no pager", 1 for "use pager", and -1 for "not specified" */
125 static int check_pager_config(const char *cmd)
126 {
127 	int err;
128 	struct pager_config c;
129 	c.cmd = cmd;
130 	c.val = -1;
131 	err = perf_config(pager_command_config, &c);
132 	return err ?: c.val;
133 }
134 
135 static int browser_command_config(const char *var, const char *value, void *data)
136 {
137 	struct pager_config *c = data;
138 	if (same_cmd_with_prefix(var, c, "tui."))
139 		c->val = perf_config_bool(var, value);
140 	if (same_cmd_with_prefix(var, c, "gtk."))
141 		c->val = perf_config_bool(var, value) ? 2 : 0;
142 	return 0;
143 }
144 
145 /*
146  * returns 0 for "no tui", 1 for "use tui", 2 for "use gtk",
147  * and -1 for "not specified"
148  */
149 static int check_browser_config(const char *cmd)
150 {
151 	int err;
152 	struct pager_config c;
153 	c.cmd = cmd;
154 	c.val = -1;
155 	err = perf_config(browser_command_config, &c);
156 	return err ?: c.val;
157 }
158 
159 static void commit_pager_choice(void)
160 {
161 	switch (use_pager) {
162 	case 0:
163 		setenv(PERF_PAGER_ENVIRONMENT, "cat", 1);
164 		break;
165 	case 1:
166 		/* setup_pager(); */
167 		break;
168 	default:
169 		break;
170 	}
171 }
172 
173 struct option options[] = {
174 	OPT_ARGUMENT("help", "help"),
175 	OPT_ARGUMENT("version", "version"),
176 	OPT_ARGUMENT("exec-path", "exec-path"),
177 	OPT_ARGUMENT("html-path", "html-path"),
178 	OPT_ARGUMENT("paginate", "paginate"),
179 	OPT_ARGUMENT("no-pager", "no-pager"),
180 	OPT_ARGUMENT("debugfs-dir", "debugfs-dir"),
181 	OPT_ARGUMENT("buildid-dir", "buildid-dir"),
182 	OPT_ARGUMENT("list-cmds", "list-cmds"),
183 	OPT_ARGUMENT("list-opts", "list-opts"),
184 	OPT_ARGUMENT("debug", "debug"),
185 	OPT_END()
186 };
187 
188 static int handle_options(const char ***argv, int *argc, int *envchanged)
189 {
190 	int handled = 0;
191 
192 	while (*argc > 0) {
193 		const char *cmd = (*argv)[0];
194 		if (cmd[0] != '-')
195 			break;
196 
197 		/*
198 		 * For legacy reasons, the "version" and "help"
199 		 * commands can be written with "--" prepended
200 		 * to make them look like flags.
201 		 */
202 		if (!strcmp(cmd, "--help") || !strcmp(cmd, "--version"))
203 			break;
204 
205 		/*
206 		 * Shortcut for '-h' and '-v' options to invoke help
207 		 * and version command.
208 		 */
209 		if (!strcmp(cmd, "-h")) {
210 			(*argv)[0] = "--help";
211 			break;
212 		}
213 
214 		if (!strcmp(cmd, "-v")) {
215 			(*argv)[0] = "--version";
216 			break;
217 		}
218 
219 		if (!strcmp(cmd, "-vv")) {
220 			(*argv)[0] = "version";
221 			version_verbose = 1;
222 			break;
223 		}
224 
225 		/*
226 		 * Check remaining flags.
227 		 */
228 		if (strstarts(cmd, CMD_EXEC_PATH)) {
229 			cmd += strlen(CMD_EXEC_PATH);
230 			if (*cmd == '=')
231 				set_argv_exec_path(cmd + 1);
232 			else {
233 				puts(get_argv_exec_path());
234 				exit(0);
235 			}
236 		} else if (!strcmp(cmd, "--html-path")) {
237 			puts(system_path(PERF_HTML_PATH));
238 			exit(0);
239 		} else if (!strcmp(cmd, "-p") || !strcmp(cmd, "--paginate")) {
240 			use_pager = 1;
241 		} else if (!strcmp(cmd, "--no-pager")) {
242 			use_pager = 0;
243 			if (envchanged)
244 				*envchanged = 1;
245 		} else if (!strcmp(cmd, "--debugfs-dir")) {
246 			if (*argc < 2) {
247 				fprintf(stderr, "No directory given for --debugfs-dir.\n");
248 				usage(perf_usage_string);
249 			}
250 			tracing_path_set((*argv)[1]);
251 			if (envchanged)
252 				*envchanged = 1;
253 			(*argv)++;
254 			(*argc)--;
255 		} else if (!strcmp(cmd, "--buildid-dir")) {
256 			if (*argc < 2) {
257 				fprintf(stderr, "No directory given for --buildid-dir.\n");
258 				usage(perf_usage_string);
259 			}
260 			set_buildid_dir((*argv)[1]);
261 			if (envchanged)
262 				*envchanged = 1;
263 			(*argv)++;
264 			(*argc)--;
265 		} else if (strstarts(cmd, CMD_DEBUGFS_DIR)) {
266 			tracing_path_set(cmd + strlen(CMD_DEBUGFS_DIR));
267 			fprintf(stderr, "dir: %s\n", tracing_path_mount());
268 			if (envchanged)
269 				*envchanged = 1;
270 		} else if (!strcmp(cmd, "--list-cmds")) {
271 			unsigned int i;
272 
273 			for (i = 0; i < ARRAY_SIZE(commands); i++) {
274 				struct cmd_struct *p = commands+i;
275 				printf("%s ", p->cmd);
276 			}
277 			putchar('\n');
278 			exit(0);
279 		} else if (!strcmp(cmd, "--list-opts")) {
280 			unsigned int i;
281 
282 			for (i = 0; i < ARRAY_SIZE(options)-1; i++) {
283 				struct option *p = options+i;
284 				printf("--%s ", p->long_name);
285 			}
286 			putchar('\n');
287 			exit(0);
288 		} else if (!strcmp(cmd, "--debug")) {
289 			if (*argc < 2) {
290 				fprintf(stderr, "No variable specified for --debug.\n");
291 				usage(perf_usage_string);
292 			}
293 			if (perf_debug_option((*argv)[1]))
294 				usage(perf_usage_string);
295 
296 			(*argv)++;
297 			(*argc)--;
298 		} else {
299 			fprintf(stderr, "Unknown option: %s\n", cmd);
300 			usage(perf_usage_string);
301 		}
302 
303 		(*argv)++;
304 		(*argc)--;
305 		handled++;
306 	}
307 	return handled;
308 }
309 
310 #define RUN_SETUP	(1<<0)
311 #define USE_PAGER	(1<<1)
312 
313 static int run_builtin(struct cmd_struct *p, int argc, const char **argv)
314 {
315 	int status;
316 	struct stat st;
317 	char sbuf[STRERR_BUFSIZE];
318 
319 	if (use_browser == -1)
320 		use_browser = check_browser_config(p->cmd);
321 
322 	if (use_pager == -1 && p->option & RUN_SETUP)
323 		use_pager = check_pager_config(p->cmd);
324 	if (use_pager == -1 && p->option & USE_PAGER)
325 		use_pager = 1;
326 	commit_pager_choice();
327 
328 	perf_env__init(&perf_env);
329 	perf_env__set_cmdline(&perf_env, argc, argv);
330 	status = p->fn(argc, argv);
331 	perf_config__exit();
332 	exit_browser(status);
333 	perf_env__exit(&perf_env);
334 	bpf__clear();
335 
336 	if (status)
337 		return status & 0xff;
338 
339 	/* Somebody closed stdout? */
340 	if (fstat(fileno(stdout), &st))
341 		return 0;
342 	/* Ignore write errors for pipes and sockets.. */
343 	if (S_ISFIFO(st.st_mode) || S_ISSOCK(st.st_mode))
344 		return 0;
345 
346 	status = 1;
347 	/* Check for ENOSPC and EIO errors.. */
348 	if (fflush(stdout)) {
349 		fprintf(stderr, "write failure on standard output: %s",
350 			str_error_r(errno, sbuf, sizeof(sbuf)));
351 		goto out;
352 	}
353 	if (ferror(stdout)) {
354 		fprintf(stderr, "unknown write failure on standard output");
355 		goto out;
356 	}
357 	if (fclose(stdout)) {
358 		fprintf(stderr, "close failed on standard output: %s",
359 			str_error_r(errno, sbuf, sizeof(sbuf)));
360 		goto out;
361 	}
362 	status = 0;
363 out:
364 	return status;
365 }
366 
367 static void handle_internal_command(int argc, const char **argv)
368 {
369 	const char *cmd = argv[0];
370 	unsigned int i;
371 
372 	/* Turn "perf cmd --help" into "perf help cmd" */
373 	if (argc > 1 && !strcmp(argv[1], "--help")) {
374 		argv[1] = argv[0];
375 		argv[0] = cmd = "help";
376 	}
377 
378 	for (i = 0; i < ARRAY_SIZE(commands); i++) {
379 		struct cmd_struct *p = commands+i;
380 		if (p->fn == NULL)
381 			continue;
382 		if (strcmp(p->cmd, cmd))
383 			continue;
384 		exit(run_builtin(p, argc, argv));
385 	}
386 }
387 
388 static void execv_dashed_external(const char **argv)
389 {
390 	char *cmd;
391 	const char *tmp;
392 	int status;
393 
394 	if (asprintf(&cmd, "perf-%s", argv[0]) < 0)
395 		goto do_die;
396 
397 	/*
398 	 * argv[0] must be the perf command, but the argv array
399 	 * belongs to the caller, and may be reused in
400 	 * subsequent loop iterations. Save argv[0] and
401 	 * restore it on error.
402 	 */
403 	tmp = argv[0];
404 	argv[0] = cmd;
405 
406 	/*
407 	 * if we fail because the command is not found, it is
408 	 * OK to return. Otherwise, we just pass along the status code.
409 	 */
410 	status = run_command_v_opt(argv, 0);
411 	if (status != -ERR_RUN_COMMAND_EXEC) {
412 		if (IS_RUN_COMMAND_ERR(status)) {
413 do_die:
414 			pr_err("FATAL: unable to run '%s'", argv[0]);
415 			status = -128;
416 		}
417 		exit(-status);
418 	}
419 	errno = ENOENT; /* as if we called execvp */
420 
421 	argv[0] = tmp;
422 	zfree(&cmd);
423 }
424 
425 static int run_argv(int *argcp, const char ***argv)
426 {
427 	/* See if it's an internal command */
428 	handle_internal_command(*argcp, *argv);
429 
430 	/* .. then try the external ones */
431 	execv_dashed_external(*argv);
432 	return 0;
433 }
434 
435 static void pthread__block_sigwinch(void)
436 {
437 	sigset_t set;
438 
439 	sigemptyset(&set);
440 	sigaddset(&set, SIGWINCH);
441 	pthread_sigmask(SIG_BLOCK, &set, NULL);
442 }
443 
444 void pthread__unblock_sigwinch(void)
445 {
446 	sigset_t set;
447 
448 	sigemptyset(&set);
449 	sigaddset(&set, SIGWINCH);
450 	pthread_sigmask(SIG_UNBLOCK, &set, NULL);
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 	return 1;
578 }
579