xref: /openbmc/linux/tools/perf/perf.c (revision ac5f3136) 
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 	{ "buildid-cache", cmd_buildid_cache, 0 },
59 	{ "buildid-list", cmd_buildid_list, 0 },
60 	{ "config",	cmd_config,	0 },
61 	{ "c2c",	cmd_c2c,	0 },
62 	{ "diff",	cmd_diff,	0 },
63 	{ "evlist",	cmd_evlist,	0 },
64 	{ "help",	cmd_help,	0 },
65 	{ "kallsyms",	cmd_kallsyms,	0 },
66 	{ "list",	cmd_list,	0 },
67 	{ "record",	cmd_record,	0 },
68 	{ "report",	cmd_report,	0 },
69 	{ "bench",	cmd_bench,	0 },
70 	{ "stat",	cmd_stat,	0 },
71 	{ "timechart",	cmd_timechart,	0 },
72 	{ "top",	cmd_top,	0 },
73 	{ "annotate",	cmd_annotate,	0 },
74 	{ "version",	cmd_version,	0 },
75 	{ "script",	cmd_script,	0 },
76 	{ "sched",	cmd_sched,	0 },
77 #ifdef HAVE_LIBELF_SUPPORT
78 	{ "probe",	cmd_probe,	0 },
79 #endif
80 	{ "kmem",	cmd_kmem,	0 },
81 	{ "lock",	cmd_lock,	0 },
82 	{ "kvm",	cmd_kvm,	0 },
83 	{ "test",	cmd_test,	0 },
84 #if defined(HAVE_LIBAUDIT_SUPPORT) || defined(HAVE_SYSCALL_TABLE_SUPPORT)
85 	{ "trace",	cmd_trace,	0 },
86 #endif
87 	{ "inject",	cmd_inject,	0 },
88 	{ "mem",	cmd_mem,	0 },
89 	{ "data",	cmd_data,	0 },
90 	{ "ftrace",	cmd_ftrace,	0 },
91 	{ "daemon",	cmd_daemon,	0 },
92 };
93 
94 struct pager_config {
95 	const char *cmd;
96 	int val;
97 };
98 
99 static int pager_command_config(const char *var, const char *value, void *data)
100 {
101 	struct pager_config *c = data;
102 	if (strstarts(var, "pager.") && !strcmp(var + 6, c->cmd))
103 		c->val = perf_config_bool(var, value);
104 	return 0;
105 }
106 
107 /* returns 0 for "no pager", 1 for "use pager", and -1 for "not specified" */
108 static int check_pager_config(const char *cmd)
109 {
110 	int err;
111 	struct pager_config c;
112 	c.cmd = cmd;
113 	c.val = -1;
114 	err = perf_config(pager_command_config, &c);
115 	return err ?: c.val;
116 }
117 
118 static int browser_command_config(const char *var, const char *value, void *data)
119 {
120 	struct pager_config *c = data;
121 	if (strstarts(var, "tui.") && !strcmp(var + 4, c->cmd))
122 		c->val = perf_config_bool(var, value);
123 	if (strstarts(var, "gtk.") && !strcmp(var + 4, c->cmd))
124 		c->val = perf_config_bool(var, value) ? 2 : 0;
125 	return 0;
126 }
127 
128 /*
129  * returns 0 for "no tui", 1 for "use tui", 2 for "use gtk",
130  * and -1 for "not specified"
131  */
132 static int check_browser_config(const char *cmd)
133 {
134 	int err;
135 	struct pager_config c;
136 	c.cmd = cmd;
137 	c.val = -1;
138 	err = perf_config(browser_command_config, &c);
139 	return err ?: c.val;
140 }
141 
142 static void commit_pager_choice(void)
143 {
144 	switch (use_pager) {
145 	case 0:
146 		setenv(PERF_PAGER_ENVIRONMENT, "cat", 1);
147 		break;
148 	case 1:
149 		/* setup_pager(); */
150 		break;
151 	default:
152 		break;
153 	}
154 }
155 
156 struct option options[] = {
157 	OPT_ARGUMENT("help", "help"),
158 	OPT_ARGUMENT("version", "version"),
159 	OPT_ARGUMENT("exec-path", "exec-path"),
160 	OPT_ARGUMENT("html-path", "html-path"),
161 	OPT_ARGUMENT("paginate", "paginate"),
162 	OPT_ARGUMENT("no-pager", "no-pager"),
163 	OPT_ARGUMENT("debugfs-dir", "debugfs-dir"),
164 	OPT_ARGUMENT("buildid-dir", "buildid-dir"),
165 	OPT_ARGUMENT("list-cmds", "list-cmds"),
166 	OPT_ARGUMENT("list-opts", "list-opts"),
167 	OPT_ARGUMENT("debug", "debug"),
168 	OPT_END()
169 };
170 
171 static int handle_options(const char ***argv, int *argc, int *envchanged)
172 {
173 	int handled = 0;
174 
175 	while (*argc > 0) {
176 		const char *cmd = (*argv)[0];
177 		if (cmd[0] != '-')
178 			break;
179 
180 		/*
181 		 * For legacy reasons, the "version" and "help"
182 		 * commands can be written with "--" prepended
183 		 * to make them look like flags.
184 		 */
185 		if (!strcmp(cmd, "--help") || !strcmp(cmd, "--version"))
186 			break;
187 
188 		/*
189 		 * Shortcut for '-h' and '-v' options to invoke help
190 		 * and version command.
191 		 */
192 		if (!strcmp(cmd, "-h")) {
193 			(*argv)[0] = "--help";
194 			break;
195 		}
196 
197 		if (!strcmp(cmd, "-v")) {
198 			(*argv)[0] = "--version";
199 			break;
200 		}
201 
202 		if (!strcmp(cmd, "-vv")) {
203 			(*argv)[0] = "version";
204 			version_verbose = 1;
205 			break;
206 		}
207 
208 		/*
209 		 * Check remaining flags.
210 		 */
211 		if (strstarts(cmd, CMD_EXEC_PATH)) {
212 			cmd += strlen(CMD_EXEC_PATH);
213 			if (*cmd == '=')
214 				set_argv_exec_path(cmd + 1);
215 			else {
216 				puts(get_argv_exec_path());
217 				exit(0);
218 			}
219 		} else if (!strcmp(cmd, "--html-path")) {
220 			puts(system_path(PERF_HTML_PATH));
221 			exit(0);
222 		} else if (!strcmp(cmd, "-p") || !strcmp(cmd, "--paginate")) {
223 			use_pager = 1;
224 		} else if (!strcmp(cmd, "--no-pager")) {
225 			use_pager = 0;
226 			if (envchanged)
227 				*envchanged = 1;
228 		} else if (!strcmp(cmd, "--debugfs-dir")) {
229 			if (*argc < 2) {
230 				fprintf(stderr, "No directory given for --debugfs-dir.\n");
231 				usage(perf_usage_string);
232 			}
233 			tracing_path_set((*argv)[1]);
234 			if (envchanged)
235 				*envchanged = 1;
236 			(*argv)++;
237 			(*argc)--;
238 		} else if (!strcmp(cmd, "--buildid-dir")) {
239 			if (*argc < 2) {
240 				fprintf(stderr, "No directory given for --buildid-dir.\n");
241 				usage(perf_usage_string);
242 			}
243 			set_buildid_dir((*argv)[1]);
244 			if (envchanged)
245 				*envchanged = 1;
246 			(*argv)++;
247 			(*argc)--;
248 		} else if (strstarts(cmd, CMD_DEBUGFS_DIR)) {
249 			tracing_path_set(cmd + strlen(CMD_DEBUGFS_DIR));
250 			fprintf(stderr, "dir: %s\n", tracing_path_mount());
251 			if (envchanged)
252 				*envchanged = 1;
253 		} else if (!strcmp(cmd, "--list-cmds")) {
254 			unsigned int i;
255 
256 			for (i = 0; i < ARRAY_SIZE(commands); i++) {
257 				struct cmd_struct *p = commands+i;
258 				printf("%s ", p->cmd);
259 			}
260 			putchar('\n');
261 			exit(0);
262 		} else if (!strcmp(cmd, "--list-opts")) {
263 			unsigned int i;
264 
265 			for (i = 0; i < ARRAY_SIZE(options)-1; i++) {
266 				struct option *p = options+i;
267 				printf("--%s ", p->long_name);
268 			}
269 			putchar('\n');
270 			exit(0);
271 		} else if (!strcmp(cmd, "--debug")) {
272 			if (*argc < 2) {
273 				fprintf(stderr, "No variable specified for --debug.\n");
274 				usage(perf_usage_string);
275 			}
276 			if (perf_debug_option((*argv)[1]))
277 				usage(perf_usage_string);
278 
279 			(*argv)++;
280 			(*argc)--;
281 		} else {
282 			fprintf(stderr, "Unknown option: %s\n", cmd);
283 			usage(perf_usage_string);
284 		}
285 
286 		(*argv)++;
287 		(*argc)--;
288 		handled++;
289 	}
290 	return handled;
291 }
292 
293 #define RUN_SETUP	(1<<0)
294 #define USE_PAGER	(1<<1)
295 
296 static int run_builtin(struct cmd_struct *p, int argc, const char **argv)
297 {
298 	int status;
299 	struct stat st;
300 	char sbuf[STRERR_BUFSIZE];
301 
302 	if (use_browser == -1)
303 		use_browser = check_browser_config(p->cmd);
304 
305 	if (use_pager == -1 && p->option & RUN_SETUP)
306 		use_pager = check_pager_config(p->cmd);
307 	if (use_pager == -1 && p->option & USE_PAGER)
308 		use_pager = 1;
309 	commit_pager_choice();
310 
311 	perf_env__init(&perf_env);
312 	perf_env__set_cmdline(&perf_env, argc, argv);
313 	status = p->fn(argc, argv);
314 	perf_config__exit();
315 	exit_browser(status);
316 	perf_env__exit(&perf_env);
317 	bpf__clear();
318 
319 	if (status)
320 		return status & 0xff;
321 
322 	/* Somebody closed stdout? */
323 	if (fstat(fileno(stdout), &st))
324 		return 0;
325 	/* Ignore write errors for pipes and sockets.. */
326 	if (S_ISFIFO(st.st_mode) || S_ISSOCK(st.st_mode))
327 		return 0;
328 
329 	status = 1;
330 	/* Check for ENOSPC and EIO errors.. */
331 	if (fflush(stdout)) {
332 		fprintf(stderr, "write failure on standard output: %s",
333 			str_error_r(errno, sbuf, sizeof(sbuf)));
334 		goto out;
335 	}
336 	if (ferror(stdout)) {
337 		fprintf(stderr, "unknown write failure on standard output");
338 		goto out;
339 	}
340 	if (fclose(stdout)) {
341 		fprintf(stderr, "close failed on standard output: %s",
342 			str_error_r(errno, sbuf, sizeof(sbuf)));
343 		goto out;
344 	}
345 	status = 0;
346 out:
347 	return status;
348 }
349 
350 static void handle_internal_command(int argc, const char **argv)
351 {
352 	const char *cmd = argv[0];
353 	unsigned int i;
354 
355 	/* Turn "perf cmd --help" into "perf help cmd" */
356 	if (argc > 1 && !strcmp(argv[1], "--help")) {
357 		argv[1] = argv[0];
358 		argv[0] = cmd = "help";
359 	}
360 
361 	for (i = 0; i < ARRAY_SIZE(commands); i++) {
362 		struct cmd_struct *p = commands+i;
363 		if (strcmp(p->cmd, cmd))
364 			continue;
365 		exit(run_builtin(p, argc, argv));
366 	}
367 }
368 
369 static void execv_dashed_external(const char **argv)
370 {
371 	char *cmd;
372 	const char *tmp;
373 	int status;
374 
375 	if (asprintf(&cmd, "perf-%s", argv[0]) < 0)
376 		goto do_die;
377 
378 	/*
379 	 * argv[0] must be the perf command, but the argv array
380 	 * belongs to the caller, and may be reused in
381 	 * subsequent loop iterations. Save argv[0] and
382 	 * restore it on error.
383 	 */
384 	tmp = argv[0];
385 	argv[0] = cmd;
386 
387 	/*
388 	 * if we fail because the command is not found, it is
389 	 * OK to return. Otherwise, we just pass along the status code.
390 	 */
391 	status = run_command_v_opt(argv, 0);
392 	if (status != -ERR_RUN_COMMAND_EXEC) {
393 		if (IS_RUN_COMMAND_ERR(status)) {
394 do_die:
395 			pr_err("FATAL: unable to run '%s'", argv[0]);
396 			status = -128;
397 		}
398 		exit(-status);
399 	}
400 	errno = ENOENT; /* as if we called execvp */
401 
402 	argv[0] = tmp;
403 	zfree(&cmd);
404 }
405 
406 static int run_argv(int *argcp, const char ***argv)
407 {
408 	/* See if it's an internal command */
409 	handle_internal_command(*argcp, *argv);
410 
411 	/* .. then try the external ones */
412 	execv_dashed_external(*argv);
413 	return 0;
414 }
415 
416 static void pthread__block_sigwinch(void)
417 {
418 	sigset_t set;
419 
420 	sigemptyset(&set);
421 	sigaddset(&set, SIGWINCH);
422 	pthread_sigmask(SIG_BLOCK, &set, NULL);
423 }
424 
425 void pthread__unblock_sigwinch(void)
426 {
427 	sigset_t set;
428 
429 	sigemptyset(&set);
430 	sigaddset(&set, SIGWINCH);
431 	pthread_sigmask(SIG_UNBLOCK, &set, NULL);
432 }
433 
434 static int libperf_print(enum libperf_print_level level,
435 			 const char *fmt, va_list ap)
436 {
437 	return eprintf(level, verbose, fmt, ap);
438 }
439 
440 int main(int argc, const char **argv)
441 {
442 	int err;
443 	const char *cmd;
444 	char sbuf[STRERR_BUFSIZE];
445 
446 	perf_debug_setup();
447 
448 	/* libsubcmd init */
449 	exec_cmd_init("perf", PREFIX, PERF_EXEC_PATH, EXEC_PATH_ENVIRONMENT);
450 	pager_init(PERF_PAGER_ENVIRONMENT);
451 
452 	libperf_init(libperf_print);
453 
454 	cmd = extract_argv0_path(argv[0]);
455 	if (!cmd)
456 		cmd = "perf-help";
457 
458 	srandom(time(NULL));
459 
460 	/* Setting $PERF_CONFIG makes perf read _only_ the given config file. */
461 	config_exclusive_filename = getenv("PERF_CONFIG");
462 
463 	err = perf_config(perf_default_config, NULL);
464 	if (err)
465 		return err;
466 	set_buildid_dir(NULL);
467 
468 	/*
469 	 * "perf-xxxx" is the same as "perf xxxx", but we obviously:
470 	 *
471 	 *  - cannot take flags in between the "perf" and the "xxxx".
472 	 *  - cannot execute it externally (since it would just do
473 	 *    the same thing over again)
474 	 *
475 	 * So we just directly call the internal command handler. If that one
476 	 * fails to handle this, then maybe we just run a renamed perf binary
477 	 * that contains a dash in its name. To handle this scenario, we just
478 	 * fall through and ignore the "xxxx" part of the command string.
479 	 */
480 	if (strstarts(cmd, "perf-")) {
481 		cmd += 5;
482 		argv[0] = cmd;
483 		handle_internal_command(argc, argv);
484 		/*
485 		 * If the command is handled, the above function does not
486 		 * return undo changes and fall through in such a case.
487 		 */
488 		cmd -= 5;
489 		argv[0] = cmd;
490 	}
491 	if (strstarts(cmd, "trace")) {
492 #if defined(HAVE_LIBAUDIT_SUPPORT) || defined(HAVE_SYSCALL_TABLE_SUPPORT)
493 		setup_path();
494 		argv[0] = "trace";
495 		return cmd_trace(argc, argv);
496 #else
497 		fprintf(stderr,
498 			"trace command not available: missing audit-libs devel package at build time.\n");
499 		goto out;
500 #endif
501 	}
502 	/* Look for flags.. */
503 	argv++;
504 	argc--;
505 	handle_options(&argv, &argc, NULL);
506 	commit_pager_choice();
507 
508 	if (argc > 0) {
509 		if (strstarts(argv[0], "--"))
510 			argv[0] += 2;
511 	} else {
512 		/* The user didn't specify a command; give them help */
513 		printf("\n usage: %s\n\n", perf_usage_string);
514 		list_common_cmds_help();
515 		printf("\n %s\n\n", perf_more_info_string);
516 		goto out;
517 	}
518 	cmd = argv[0];
519 
520 	test_attr__init();
521 
522 	/*
523 	 * We use PATH to find perf commands, but we prepend some higher
524 	 * precedence paths: the "--exec-path" option, the PERF_EXEC_PATH
525 	 * environment, and the $(perfexecdir) from the Makefile at build
526 	 * time.
527 	 */
528 	setup_path();
529 	/*
530 	 * Block SIGWINCH notifications so that the thread that wants it can
531 	 * unblock and get syscalls like select interrupted instead of waiting
532 	 * forever while the signal goes to some other non interested thread.
533 	 */
534 	pthread__block_sigwinch();
535 
536 	while (1) {
537 		static int done_help;
538 
539 		run_argv(&argc, &argv);
540 
541 		if (errno != ENOENT)
542 			break;
543 
544 		if (!done_help) {
545 			cmd = argv[0] = help_unknown_cmd(cmd);
546 			done_help = 1;
547 		} else
548 			break;
549 	}
550 
551 	fprintf(stderr, "Failed to run command '%s': %s\n",
552 		cmd, str_error_r(errno, sbuf, sizeof(sbuf)));
553 out:
554 	return 1;
555 }
556