xref: /openbmc/linux/tools/perf/perf.c (revision 884caada) 
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 };
92 
93 struct pager_config {
94 	const char *cmd;
95 	int val;
96 };
97 
98 static int pager_command_config(const char *var, const char *value, void *data)
99 {
100 	struct pager_config *c = data;
101 	if (strstarts(var, "pager.") && !strcmp(var + 6, c->cmd))
102 		c->val = perf_config_bool(var, value);
103 	return 0;
104 }
105 
106 /* returns 0 for "no pager", 1 for "use pager", and -1 for "not specified" */
107 static int check_pager_config(const char *cmd)
108 {
109 	int err;
110 	struct pager_config c;
111 	c.cmd = cmd;
112 	c.val = -1;
113 	err = perf_config(pager_command_config, &c);
114 	return err ?: c.val;
115 }
116 
117 static int browser_command_config(const char *var, const char *value, void *data)
118 {
119 	struct pager_config *c = data;
120 	if (strstarts(var, "tui.") && !strcmp(var + 4, c->cmd))
121 		c->val = perf_config_bool(var, value);
122 	if (strstarts(var, "gtk.") && !strcmp(var + 4, c->cmd))
123 		c->val = perf_config_bool(var, value) ? 2 : 0;
124 	return 0;
125 }
126 
127 /*
128  * returns 0 for "no tui", 1 for "use tui", 2 for "use gtk",
129  * and -1 for "not specified"
130  */
131 static int check_browser_config(const char *cmd)
132 {
133 	int err;
134 	struct pager_config c;
135 	c.cmd = cmd;
136 	c.val = -1;
137 	err = perf_config(browser_command_config, &c);
138 	return err ?: c.val;
139 }
140 
141 static void commit_pager_choice(void)
142 {
143 	switch (use_pager) {
144 	case 0:
145 		setenv(PERF_PAGER_ENVIRONMENT, "cat", 1);
146 		break;
147 	case 1:
148 		/* setup_pager(); */
149 		break;
150 	default:
151 		break;
152 	}
153 }
154 
155 struct option options[] = {
156 	OPT_ARGUMENT("help", "help"),
157 	OPT_ARGUMENT("version", "version"),
158 	OPT_ARGUMENT("exec-path", "exec-path"),
159 	OPT_ARGUMENT("html-path", "html-path"),
160 	OPT_ARGUMENT("paginate", "paginate"),
161 	OPT_ARGUMENT("no-pager", "no-pager"),
162 	OPT_ARGUMENT("debugfs-dir", "debugfs-dir"),
163 	OPT_ARGUMENT("buildid-dir", "buildid-dir"),
164 	OPT_ARGUMENT("list-cmds", "list-cmds"),
165 	OPT_ARGUMENT("list-opts", "list-opts"),
166 	OPT_ARGUMENT("debug", "debug"),
167 	OPT_END()
168 };
169 
170 static int handle_options(const char ***argv, int *argc, int *envchanged)
171 {
172 	int handled = 0;
173 
174 	while (*argc > 0) {
175 		const char *cmd = (*argv)[0];
176 		if (cmd[0] != '-')
177 			break;
178 
179 		/*
180 		 * For legacy reasons, the "version" and "help"
181 		 * commands can be written with "--" prepended
182 		 * to make them look like flags.
183 		 */
184 		if (!strcmp(cmd, "--help") || !strcmp(cmd, "--version"))
185 			break;
186 
187 		/*
188 		 * Shortcut for '-h' and '-v' options to invoke help
189 		 * and version command.
190 		 */
191 		if (!strcmp(cmd, "-h")) {
192 			(*argv)[0] = "--help";
193 			break;
194 		}
195 
196 		if (!strcmp(cmd, "-v")) {
197 			(*argv)[0] = "--version";
198 			break;
199 		}
200 
201 		if (!strcmp(cmd, "-vv")) {
202 			(*argv)[0] = "version";
203 			version_verbose = 1;
204 			break;
205 		}
206 
207 		/*
208 		 * Check remaining flags.
209 		 */
210 		if (strstarts(cmd, CMD_EXEC_PATH)) {
211 			cmd += strlen(CMD_EXEC_PATH);
212 			if (*cmd == '=')
213 				set_argv_exec_path(cmd + 1);
214 			else {
215 				puts(get_argv_exec_path());
216 				exit(0);
217 			}
218 		} else if (!strcmp(cmd, "--html-path")) {
219 			puts(system_path(PERF_HTML_PATH));
220 			exit(0);
221 		} else if (!strcmp(cmd, "-p") || !strcmp(cmd, "--paginate")) {
222 			use_pager = 1;
223 		} else if (!strcmp(cmd, "--no-pager")) {
224 			use_pager = 0;
225 			if (envchanged)
226 				*envchanged = 1;
227 		} else if (!strcmp(cmd, "--debugfs-dir")) {
228 			if (*argc < 2) {
229 				fprintf(stderr, "No directory given for --debugfs-dir.\n");
230 				usage(perf_usage_string);
231 			}
232 			tracing_path_set((*argv)[1]);
233 			if (envchanged)
234 				*envchanged = 1;
235 			(*argv)++;
236 			(*argc)--;
237 		} else if (!strcmp(cmd, "--buildid-dir")) {
238 			if (*argc < 2) {
239 				fprintf(stderr, "No directory given for --buildid-dir.\n");
240 				usage(perf_usage_string);
241 			}
242 			set_buildid_dir((*argv)[1]);
243 			if (envchanged)
244 				*envchanged = 1;
245 			(*argv)++;
246 			(*argc)--;
247 		} else if (strstarts(cmd, CMD_DEBUGFS_DIR)) {
248 			tracing_path_set(cmd + strlen(CMD_DEBUGFS_DIR));
249 			fprintf(stderr, "dir: %s\n", tracing_path_mount());
250 			if (envchanged)
251 				*envchanged = 1;
252 		} else if (!strcmp(cmd, "--list-cmds")) {
253 			unsigned int i;
254 
255 			for (i = 0; i < ARRAY_SIZE(commands); i++) {
256 				struct cmd_struct *p = commands+i;
257 				printf("%s ", p->cmd);
258 			}
259 			putchar('\n');
260 			exit(0);
261 		} else if (!strcmp(cmd, "--list-opts")) {
262 			unsigned int i;
263 
264 			for (i = 0; i < ARRAY_SIZE(options)-1; i++) {
265 				struct option *p = options+i;
266 				printf("--%s ", p->long_name);
267 			}
268 			putchar('\n');
269 			exit(0);
270 		} else if (!strcmp(cmd, "--debug")) {
271 			if (*argc < 2) {
272 				fprintf(stderr, "No variable specified for --debug.\n");
273 				usage(perf_usage_string);
274 			}
275 			if (perf_debug_option((*argv)[1]))
276 				usage(perf_usage_string);
277 
278 			(*argv)++;
279 			(*argc)--;
280 		} else {
281 			fprintf(stderr, "Unknown option: %s\n", cmd);
282 			usage(perf_usage_string);
283 		}
284 
285 		(*argv)++;
286 		(*argc)--;
287 		handled++;
288 	}
289 	return handled;
290 }
291 
292 #define RUN_SETUP	(1<<0)
293 #define USE_PAGER	(1<<1)
294 
295 static int run_builtin(struct cmd_struct *p, int argc, const char **argv)
296 {
297 	int status;
298 	struct stat st;
299 	char sbuf[STRERR_BUFSIZE];
300 
301 	if (use_browser == -1)
302 		use_browser = check_browser_config(p->cmd);
303 
304 	if (use_pager == -1 && p->option & RUN_SETUP)
305 		use_pager = check_pager_config(p->cmd);
306 	if (use_pager == -1 && p->option & USE_PAGER)
307 		use_pager = 1;
308 	commit_pager_choice();
309 
310 	perf_env__init(&perf_env);
311 	perf_env__set_cmdline(&perf_env, argc, argv);
312 	status = p->fn(argc, argv);
313 	perf_config__exit();
314 	exit_browser(status);
315 	perf_env__exit(&perf_env);
316 	bpf__clear();
317 
318 	if (status)
319 		return status & 0xff;
320 
321 	/* Somebody closed stdout? */
322 	if (fstat(fileno(stdout), &st))
323 		return 0;
324 	/* Ignore write errors for pipes and sockets.. */
325 	if (S_ISFIFO(st.st_mode) || S_ISSOCK(st.st_mode))
326 		return 0;
327 
328 	status = 1;
329 	/* Check for ENOSPC and EIO errors.. */
330 	if (fflush(stdout)) {
331 		fprintf(stderr, "write failure on standard output: %s",
332 			str_error_r(errno, sbuf, sizeof(sbuf)));
333 		goto out;
334 	}
335 	if (ferror(stdout)) {
336 		fprintf(stderr, "unknown write failure on standard output");
337 		goto out;
338 	}
339 	if (fclose(stdout)) {
340 		fprintf(stderr, "close failed on standard output: %s",
341 			str_error_r(errno, sbuf, sizeof(sbuf)));
342 		goto out;
343 	}
344 	status = 0;
345 out:
346 	return status;
347 }
348 
349 static void handle_internal_command(int argc, const char **argv)
350 {
351 	const char *cmd = argv[0];
352 	unsigned int i;
353 
354 	/* Turn "perf cmd --help" into "perf help cmd" */
355 	if (argc > 1 && !strcmp(argv[1], "--help")) {
356 		argv[1] = argv[0];
357 		argv[0] = cmd = "help";
358 	}
359 
360 	for (i = 0; i < ARRAY_SIZE(commands); i++) {
361 		struct cmd_struct *p = commands+i;
362 		if (strcmp(p->cmd, cmd))
363 			continue;
364 		exit(run_builtin(p, argc, argv));
365 	}
366 }
367 
368 static void execv_dashed_external(const char **argv)
369 {
370 	char *cmd;
371 	const char *tmp;
372 	int status;
373 
374 	if (asprintf(&cmd, "perf-%s", argv[0]) < 0)
375 		goto do_die;
376 
377 	/*
378 	 * argv[0] must be the perf command, but the argv array
379 	 * belongs to the caller, and may be reused in
380 	 * subsequent loop iterations. Save argv[0] and
381 	 * restore it on error.
382 	 */
383 	tmp = argv[0];
384 	argv[0] = cmd;
385 
386 	/*
387 	 * if we fail because the command is not found, it is
388 	 * OK to return. Otherwise, we just pass along the status code.
389 	 */
390 	status = run_command_v_opt(argv, 0);
391 	if (status != -ERR_RUN_COMMAND_EXEC) {
392 		if (IS_RUN_COMMAND_ERR(status)) {
393 do_die:
394 			pr_err("FATAL: unable to run '%s'", argv[0]);
395 			status = -128;
396 		}
397 		exit(-status);
398 	}
399 	errno = ENOENT; /* as if we called execvp */
400 
401 	argv[0] = tmp;
402 	zfree(&cmd);
403 }
404 
405 static int run_argv(int *argcp, const char ***argv)
406 {
407 	/* See if it's an internal command */
408 	handle_internal_command(*argcp, *argv);
409 
410 	/* .. then try the external ones */
411 	execv_dashed_external(*argv);
412 	return 0;
413 }
414 
415 static void pthread__block_sigwinch(void)
416 {
417 	sigset_t set;
418 
419 	sigemptyset(&set);
420 	sigaddset(&set, SIGWINCH);
421 	pthread_sigmask(SIG_BLOCK, &set, NULL);
422 }
423 
424 void pthread__unblock_sigwinch(void)
425 {
426 	sigset_t set;
427 
428 	sigemptyset(&set);
429 	sigaddset(&set, SIGWINCH);
430 	pthread_sigmask(SIG_UNBLOCK, &set, NULL);
431 }
432 
433 static int libperf_print(enum libperf_print_level level,
434 			 const char *fmt, va_list ap)
435 {
436 	return eprintf(level, verbose, fmt, ap);
437 }
438 
439 int main(int argc, const char **argv)
440 {
441 	int err;
442 	const char *cmd;
443 	char sbuf[STRERR_BUFSIZE];
444 
445 	/* libsubcmd init */
446 	exec_cmd_init("perf", PREFIX, PERF_EXEC_PATH, EXEC_PATH_ENVIRONMENT);
447 	pager_init(PERF_PAGER_ENVIRONMENT);
448 
449 	libperf_init(libperf_print);
450 
451 	cmd = extract_argv0_path(argv[0]);
452 	if (!cmd)
453 		cmd = "perf-help";
454 
455 	srandom(time(NULL));
456 
457 	/* Setting $PERF_CONFIG makes perf read _only_ the given config file. */
458 	config_exclusive_filename = getenv("PERF_CONFIG");
459 
460 	err = perf_config(perf_default_config, NULL);
461 	if (err)
462 		return err;
463 	set_buildid_dir(NULL);
464 
465 	/*
466 	 * "perf-xxxx" is the same as "perf xxxx", but we obviously:
467 	 *
468 	 *  - cannot take flags in between the "perf" and the "xxxx".
469 	 *  - cannot execute it externally (since it would just do
470 	 *    the same thing over again)
471 	 *
472 	 * So we just directly call the internal command handler. If that one
473 	 * fails to handle this, then maybe we just run a renamed perf binary
474 	 * that contains a dash in its name. To handle this scenario, we just
475 	 * fall through and ignore the "xxxx" part of the command string.
476 	 */
477 	if (strstarts(cmd, "perf-")) {
478 		cmd += 5;
479 		argv[0] = cmd;
480 		handle_internal_command(argc, argv);
481 		/*
482 		 * If the command is handled, the above function does not
483 		 * return undo changes and fall through in such a case.
484 		 */
485 		cmd -= 5;
486 		argv[0] = cmd;
487 	}
488 	if (strstarts(cmd, "trace")) {
489 #if defined(HAVE_LIBAUDIT_SUPPORT) || defined(HAVE_SYSCALL_TABLE_SUPPORT)
490 		setup_path();
491 		argv[0] = "trace";
492 		return cmd_trace(argc, argv);
493 #else
494 		fprintf(stderr,
495 			"trace command not available: missing audit-libs devel package at build time.\n");
496 		goto out;
497 #endif
498 	}
499 	/* Look for flags.. */
500 	argv++;
501 	argc--;
502 	handle_options(&argv, &argc, NULL);
503 	commit_pager_choice();
504 
505 	if (argc > 0) {
506 		if (strstarts(argv[0], "--"))
507 			argv[0] += 2;
508 	} else {
509 		/* The user didn't specify a command; give them help */
510 		printf("\n usage: %s\n\n", perf_usage_string);
511 		list_common_cmds_help();
512 		printf("\n %s\n\n", perf_more_info_string);
513 		goto out;
514 	}
515 	cmd = argv[0];
516 
517 	test_attr__init();
518 
519 	/*
520 	 * We use PATH to find perf commands, but we prepend some higher
521 	 * precedence paths: the "--exec-path" option, the PERF_EXEC_PATH
522 	 * environment, and the $(perfexecdir) from the Makefile at build
523 	 * time.
524 	 */
525 	setup_path();
526 	/*
527 	 * Block SIGWINCH notifications so that the thread that wants it can
528 	 * unblock and get syscalls like select interrupted instead of waiting
529 	 * forever while the signal goes to some other non interested thread.
530 	 */
531 	pthread__block_sigwinch();
532 
533 	perf_debug_setup();
534 
535 	while (1) {
536 		static int done_help;
537 
538 		run_argv(&argc, &argv);
539 
540 		if (errno != ENOENT)
541 			break;
542 
543 		if (!done_help) {
544 			cmd = argv[0] = help_unknown_cmd(cmd);
545 			done_help = 1;
546 		} else
547 			break;
548 	}
549 
550 	fprintf(stderr, "Failed to run command '%s': %s\n",
551 		cmd, str_error_r(errno, sbuf, sizeof(sbuf)));
552 out:
553 	return 1;
554 }
555