xref: /openbmc/linux/tools/perf/perf.c (revision 0df499ea) 
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 int pager_command_config(const char *var, const char *value, void *data)
103 {
104 	struct pager_config *c = data;
105 	if (strstarts(var, "pager.") && !strcmp(var + 6, c->cmd))
106 		c->val = perf_config_bool(var, value);
107 	return 0;
108 }
109 
110 /* returns 0 for "no pager", 1 for "use pager", and -1 for "not specified" */
111 static int check_pager_config(const char *cmd)
112 {
113 	int err;
114 	struct pager_config c;
115 	c.cmd = cmd;
116 	c.val = -1;
117 	err = perf_config(pager_command_config, &c);
118 	return err ?: c.val;
119 }
120 
121 static int browser_command_config(const char *var, const char *value, void *data)
122 {
123 	struct pager_config *c = data;
124 	if (strstarts(var, "tui.") && !strcmp(var + 4, c->cmd))
125 		c->val = perf_config_bool(var, value);
126 	if (strstarts(var, "gtk.") && !strcmp(var + 4, c->cmd))
127 		c->val = perf_config_bool(var, value) ? 2 : 0;
128 	return 0;
129 }
130 
131 /*
132  * returns 0 for "no tui", 1 for "use tui", 2 for "use gtk",
133  * and -1 for "not specified"
134  */
135 static int check_browser_config(const char *cmd)
136 {
137 	int err;
138 	struct pager_config c;
139 	c.cmd = cmd;
140 	c.val = -1;
141 	err = perf_config(browser_command_config, &c);
142 	return err ?: c.val;
143 }
144 
145 static void commit_pager_choice(void)
146 {
147 	switch (use_pager) {
148 	case 0:
149 		setenv(PERF_PAGER_ENVIRONMENT, "cat", 1);
150 		break;
151 	case 1:
152 		/* setup_pager(); */
153 		break;
154 	default:
155 		break;
156 	}
157 }
158 
159 struct option options[] = {
160 	OPT_ARGUMENT("help", "help"),
161 	OPT_ARGUMENT("version", "version"),
162 	OPT_ARGUMENT("exec-path", "exec-path"),
163 	OPT_ARGUMENT("html-path", "html-path"),
164 	OPT_ARGUMENT("paginate", "paginate"),
165 	OPT_ARGUMENT("no-pager", "no-pager"),
166 	OPT_ARGUMENT("debugfs-dir", "debugfs-dir"),
167 	OPT_ARGUMENT("buildid-dir", "buildid-dir"),
168 	OPT_ARGUMENT("list-cmds", "list-cmds"),
169 	OPT_ARGUMENT("list-opts", "list-opts"),
170 	OPT_ARGUMENT("debug", "debug"),
171 	OPT_END()
172 };
173 
174 static int handle_options(const char ***argv, int *argc, int *envchanged)
175 {
176 	int handled = 0;
177 
178 	while (*argc > 0) {
179 		const char *cmd = (*argv)[0];
180 		if (cmd[0] != '-')
181 			break;
182 
183 		/*
184 		 * For legacy reasons, the "version" and "help"
185 		 * commands can be written with "--" prepended
186 		 * to make them look like flags.
187 		 */
188 		if (!strcmp(cmd, "--help") || !strcmp(cmd, "--version"))
189 			break;
190 
191 		/*
192 		 * Shortcut for '-h' and '-v' options to invoke help
193 		 * and version command.
194 		 */
195 		if (!strcmp(cmd, "-h")) {
196 			(*argv)[0] = "--help";
197 			break;
198 		}
199 
200 		if (!strcmp(cmd, "-v")) {
201 			(*argv)[0] = "--version";
202 			break;
203 		}
204 
205 		if (!strcmp(cmd, "-vv")) {
206 			(*argv)[0] = "version";
207 			version_verbose = 1;
208 			break;
209 		}
210 
211 		/*
212 		 * Check remaining flags.
213 		 */
214 		if (strstarts(cmd, CMD_EXEC_PATH)) {
215 			cmd += strlen(CMD_EXEC_PATH);
216 			if (*cmd == '=')
217 				set_argv_exec_path(cmd + 1);
218 			else {
219 				puts(get_argv_exec_path());
220 				exit(0);
221 			}
222 		} else if (!strcmp(cmd, "--html-path")) {
223 			puts(system_path(PERF_HTML_PATH));
224 			exit(0);
225 		} else if (!strcmp(cmd, "-p") || !strcmp(cmd, "--paginate")) {
226 			use_pager = 1;
227 		} else if (!strcmp(cmd, "--no-pager")) {
228 			use_pager = 0;
229 			if (envchanged)
230 				*envchanged = 1;
231 		} else if (!strcmp(cmd, "--debugfs-dir")) {
232 			if (*argc < 2) {
233 				fprintf(stderr, "No directory given for --debugfs-dir.\n");
234 				usage(perf_usage_string);
235 			}
236 			tracing_path_set((*argv)[1]);
237 			if (envchanged)
238 				*envchanged = 1;
239 			(*argv)++;
240 			(*argc)--;
241 		} else if (!strcmp(cmd, "--buildid-dir")) {
242 			if (*argc < 2) {
243 				fprintf(stderr, "No directory given for --buildid-dir.\n");
244 				usage(perf_usage_string);
245 			}
246 			set_buildid_dir((*argv)[1]);
247 			if (envchanged)
248 				*envchanged = 1;
249 			(*argv)++;
250 			(*argc)--;
251 		} else if (strstarts(cmd, CMD_DEBUGFS_DIR)) {
252 			tracing_path_set(cmd + strlen(CMD_DEBUGFS_DIR));
253 			fprintf(stderr, "dir: %s\n", tracing_path_mount());
254 			if (envchanged)
255 				*envchanged = 1;
256 		} else if (!strcmp(cmd, "--list-cmds")) {
257 			unsigned int i;
258 
259 			for (i = 0; i < ARRAY_SIZE(commands); i++) {
260 				struct cmd_struct *p = commands+i;
261 				printf("%s ", p->cmd);
262 			}
263 			putchar('\n');
264 			exit(0);
265 		} else if (!strcmp(cmd, "--list-opts")) {
266 			unsigned int i;
267 
268 			for (i = 0; i < ARRAY_SIZE(options)-1; i++) {
269 				struct option *p = options+i;
270 				printf("--%s ", p->long_name);
271 			}
272 			putchar('\n');
273 			exit(0);
274 		} else if (!strcmp(cmd, "--debug")) {
275 			if (*argc < 2) {
276 				fprintf(stderr, "No variable specified for --debug.\n");
277 				usage(perf_usage_string);
278 			}
279 			if (perf_debug_option((*argv)[1]))
280 				usage(perf_usage_string);
281 
282 			(*argv)++;
283 			(*argc)--;
284 		} else {
285 			fprintf(stderr, "Unknown option: %s\n", cmd);
286 			usage(perf_usage_string);
287 		}
288 
289 		(*argv)++;
290 		(*argc)--;
291 		handled++;
292 	}
293 	return handled;
294 }
295 
296 #define RUN_SETUP	(1<<0)
297 #define USE_PAGER	(1<<1)
298 
299 static int run_builtin(struct cmd_struct *p, int argc, const char **argv)
300 {
301 	int status;
302 	struct stat st;
303 	char sbuf[STRERR_BUFSIZE];
304 
305 	if (use_browser == -1)
306 		use_browser = check_browser_config(p->cmd);
307 
308 	if (use_pager == -1 && p->option & RUN_SETUP)
309 		use_pager = check_pager_config(p->cmd);
310 	if (use_pager == -1 && p->option & USE_PAGER)
311 		use_pager = 1;
312 	commit_pager_choice();
313 
314 	perf_env__init(&perf_env);
315 	perf_env__set_cmdline(&perf_env, argc, argv);
316 	status = p->fn(argc, argv);
317 	perf_config__exit();
318 	exit_browser(status);
319 	perf_env__exit(&perf_env);
320 	bpf__clear();
321 
322 	if (status)
323 		return status & 0xff;
324 
325 	/* Somebody closed stdout? */
326 	if (fstat(fileno(stdout), &st))
327 		return 0;
328 	/* Ignore write errors for pipes and sockets.. */
329 	if (S_ISFIFO(st.st_mode) || S_ISSOCK(st.st_mode))
330 		return 0;
331 
332 	status = 1;
333 	/* Check for ENOSPC and EIO errors.. */
334 	if (fflush(stdout)) {
335 		fprintf(stderr, "write failure on standard output: %s",
336 			str_error_r(errno, sbuf, sizeof(sbuf)));
337 		goto out;
338 	}
339 	if (ferror(stdout)) {
340 		fprintf(stderr, "unknown write failure on standard output");
341 		goto out;
342 	}
343 	if (fclose(stdout)) {
344 		fprintf(stderr, "close failed on standard output: %s",
345 			str_error_r(errno, sbuf, sizeof(sbuf)));
346 		goto out;
347 	}
348 	status = 0;
349 out:
350 	return status;
351 }
352 
353 static void handle_internal_command(int argc, const char **argv)
354 {
355 	const char *cmd = argv[0];
356 	unsigned int i;
357 
358 	/* Turn "perf cmd --help" into "perf help cmd" */
359 	if (argc > 1 && !strcmp(argv[1], "--help")) {
360 		argv[1] = argv[0];
361 		argv[0] = cmd = "help";
362 	}
363 
364 	for (i = 0; i < ARRAY_SIZE(commands); i++) {
365 		struct cmd_struct *p = commands+i;
366 		if (p->fn == NULL)
367 			continue;
368 		if (strcmp(p->cmd, cmd))
369 			continue;
370 		exit(run_builtin(p, argc, argv));
371 	}
372 }
373 
374 static void execv_dashed_external(const char **argv)
375 {
376 	char *cmd;
377 	const char *tmp;
378 	int status;
379 
380 	if (asprintf(&cmd, "perf-%s", argv[0]) < 0)
381 		goto do_die;
382 
383 	/*
384 	 * argv[0] must be the perf command, but the argv array
385 	 * belongs to the caller, and may be reused in
386 	 * subsequent loop iterations. Save argv[0] and
387 	 * restore it on error.
388 	 */
389 	tmp = argv[0];
390 	argv[0] = cmd;
391 
392 	/*
393 	 * if we fail because the command is not found, it is
394 	 * OK to return. Otherwise, we just pass along the status code.
395 	 */
396 	status = run_command_v_opt(argv, 0);
397 	if (status != -ERR_RUN_COMMAND_EXEC) {
398 		if (IS_RUN_COMMAND_ERR(status)) {
399 do_die:
400 			pr_err("FATAL: unable to run '%s'", argv[0]);
401 			status = -128;
402 		}
403 		exit(-status);
404 	}
405 	errno = ENOENT; /* as if we called execvp */
406 
407 	argv[0] = tmp;
408 	zfree(&cmd);
409 }
410 
411 static int run_argv(int *argcp, const char ***argv)
412 {
413 	/* See if it's an internal command */
414 	handle_internal_command(*argcp, *argv);
415 
416 	/* .. then try the external ones */
417 	execv_dashed_external(*argv);
418 	return 0;
419 }
420 
421 static void pthread__block_sigwinch(void)
422 {
423 	sigset_t set;
424 
425 	sigemptyset(&set);
426 	sigaddset(&set, SIGWINCH);
427 	pthread_sigmask(SIG_BLOCK, &set, NULL);
428 }
429 
430 void pthread__unblock_sigwinch(void)
431 {
432 	sigset_t set;
433 
434 	sigemptyset(&set);
435 	sigaddset(&set, SIGWINCH);
436 	pthread_sigmask(SIG_UNBLOCK, &set, NULL);
437 }
438 
439 static int libperf_print(enum libperf_print_level level,
440 			 const char *fmt, va_list ap)
441 {
442 	return veprintf(level, verbose, fmt, ap);
443 }
444 
445 int main(int argc, const char **argv)
446 {
447 	int err;
448 	const char *cmd;
449 	char sbuf[STRERR_BUFSIZE];
450 
451 	perf_debug_setup();
452 
453 	/* libsubcmd init */
454 	exec_cmd_init("perf", PREFIX, PERF_EXEC_PATH, EXEC_PATH_ENVIRONMENT);
455 	pager_init(PERF_PAGER_ENVIRONMENT);
456 
457 	libperf_init(libperf_print);
458 
459 	cmd = extract_argv0_path(argv[0]);
460 	if (!cmd)
461 		cmd = "perf-help";
462 
463 	srandom(time(NULL));
464 
465 	/* Setting $PERF_CONFIG makes perf read _only_ the given config file. */
466 	config_exclusive_filename = getenv("PERF_CONFIG");
467 
468 	err = perf_config(perf_default_config, NULL);
469 	if (err)
470 		return err;
471 	set_buildid_dir(NULL);
472 
473 	/*
474 	 * "perf-xxxx" is the same as "perf xxxx", but we obviously:
475 	 *
476 	 *  - cannot take flags in between the "perf" and the "xxxx".
477 	 *  - cannot execute it externally (since it would just do
478 	 *    the same thing over again)
479 	 *
480 	 * So we just directly call the internal command handler. If that one
481 	 * fails to handle this, then maybe we just run a renamed perf binary
482 	 * that contains a dash in its name. To handle this scenario, we just
483 	 * fall through and ignore the "xxxx" part of the command string.
484 	 */
485 	if (strstarts(cmd, "perf-")) {
486 		cmd += 5;
487 		argv[0] = cmd;
488 		handle_internal_command(argc, argv);
489 		/*
490 		 * If the command is handled, the above function does not
491 		 * return undo changes and fall through in such a case.
492 		 */
493 		cmd -= 5;
494 		argv[0] = cmd;
495 	}
496 	if (strstarts(cmd, "trace")) {
497 #if defined(HAVE_LIBAUDIT_SUPPORT) || defined(HAVE_SYSCALL_TABLE_SUPPORT)
498 		setup_path();
499 		argv[0] = "trace";
500 		return cmd_trace(argc, argv);
501 #else
502 		fprintf(stderr,
503 			"trace command not available: missing audit-libs devel package at build time.\n");
504 		goto out;
505 #endif
506 	}
507 	/* Look for flags.. */
508 	argv++;
509 	argc--;
510 	handle_options(&argv, &argc, NULL);
511 	commit_pager_choice();
512 
513 	if (argc > 0) {
514 		if (strstarts(argv[0], "--"))
515 			argv[0] += 2;
516 	} else {
517 		/* The user didn't specify a command; give them help */
518 		printf("\n usage: %s\n\n", perf_usage_string);
519 		list_common_cmds_help();
520 		printf("\n %s\n\n", perf_more_info_string);
521 		goto out;
522 	}
523 	cmd = argv[0];
524 
525 	test_attr__init();
526 
527 	/*
528 	 * We use PATH to find perf commands, but we prepend some higher
529 	 * precedence paths: the "--exec-path" option, the PERF_EXEC_PATH
530 	 * environment, and the $(perfexecdir) from the Makefile at build
531 	 * time.
532 	 */
533 	setup_path();
534 	/*
535 	 * Block SIGWINCH notifications so that the thread that wants it can
536 	 * unblock and get syscalls like select interrupted instead of waiting
537 	 * forever while the signal goes to some other non interested thread.
538 	 */
539 	pthread__block_sigwinch();
540 
541 	while (1) {
542 		static int done_help;
543 
544 		run_argv(&argc, &argv);
545 
546 		if (errno != ENOENT)
547 			break;
548 
549 		if (!done_help) {
550 			cmd = argv[0] = help_unknown_cmd(cmd);
551 			done_help = 1;
552 		} else
553 			break;
554 	}
555 
556 	fprintf(stderr, "Failed to run command '%s': %s\n",
557 		cmd, str_error_r(errno, sbuf, sizeof(sbuf)));
558 out:
559 	return 1;
560 }
561