xref: /linux/tools/perf/perf.c (revision fb60211f377b69acffead3147578f86d0092a7a5) 
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 static int use_pager = -1;
43 
44 struct cmd_struct {
45 	const char *cmd;
46 	int (*fn)(int, const char **);
47 	int option;
48 };
49 
50 static struct cmd_struct commands[] = {
51 	{ "archive",	NULL,	0 },
52 	{ "buildid-cache", cmd_buildid_cache, 0 },
53 	{ "buildid-list", cmd_buildid_list, 0 },
54 	{ "config",	cmd_config,	0 },
55 	{ "c2c",	cmd_c2c,	0 },
56 	{ "diff",	cmd_diff,	0 },
57 	{ "evlist",	cmd_evlist,	0 },
58 	{ "help",	cmd_help,	0 },
59 	{ "iostat",	NULL,	0 },
60 	{ "kallsyms",	cmd_kallsyms,	0 },
61 	{ "list",	cmd_list,	0 },
62 	{ "record",	cmd_record,	0 },
63 	{ "report",	cmd_report,	0 },
64 	{ "bench",	cmd_bench,	0 },
65 	{ "stat",	cmd_stat,	0 },
66 #ifdef HAVE_LIBTRACEEVENT
67 	{ "timechart",	cmd_timechart,	0 },
68 #endif
69 	{ "top",	cmd_top,	0 },
70 	{ "annotate",	cmd_annotate,	0 },
71 	{ "version",	cmd_version,	0 },
72 	{ "script",	cmd_script,	0 },
73 #ifdef HAVE_LIBTRACEEVENT
74 	{ "sched",	cmd_sched,	0 },
75 #endif
76 #ifdef HAVE_LIBELF_SUPPORT
77 	{ "probe",	cmd_probe,	0 },
78 #endif
79 #ifdef HAVE_LIBTRACEEVENT
80 	{ "kmem",	cmd_kmem,	0 },
81 	{ "lock",	cmd_lock,	0 },
82 #endif
83 	{ "kvm",	cmd_kvm,	0 },
84 	{ "test",	cmd_test,	0 },
85 #if defined(HAVE_LIBTRACEEVENT) && (defined(HAVE_LIBAUDIT_SUPPORT) || defined(HAVE_SYSCALL_TABLE_SUPPORT))
86 	{ "trace",	cmd_trace,	0 },
87 #endif
88 	{ "inject",	cmd_inject,	0 },
89 	{ "mem",	cmd_mem,	0 },
90 	{ "data",	cmd_data,	0 },
91 	{ "ftrace",	cmd_ftrace,	0 },
92 	{ "daemon",	cmd_daemon,	0 },
93 #ifdef HAVE_LIBTRACEEVENT
94 	{ "kwork",	cmd_kwork,	0 },
95 #endif
96 };
97 
98 struct pager_config {
99 	const char *cmd;
100 	int val;
101 };
102 
103 static bool same_cmd_with_prefix(const char *var, struct pager_config *c,
104 				  const char *header)
105 {
106 	return (strstarts(var, header) && !strcmp(var + strlen(header), c->cmd));
107 }
108 
109 static int pager_command_config(const char *var, const char *value, void *data)
110 {
111 	struct pager_config *c = data;
112 	if (same_cmd_with_prefix(var, c, "pager."))
113 		c->val = perf_config_bool(var, value);
114 	return 0;
115 }
116 
117 /* returns 0 for "no pager", 1 for "use pager", and -1 for "not specified" */
118 static int check_pager_config(const char *cmd)
119 {
120 	int err;
121 	struct pager_config c;
122 	c.cmd = cmd;
123 	c.val = -1;
124 	err = perf_config(pager_command_config, &c);
125 	return err ?: c.val;
126 }
127 
128 static int browser_command_config(const char *var, const char *value, void *data)
129 {
130 	struct pager_config *c = data;
131 	if (same_cmd_with_prefix(var, c, "tui."))
132 		c->val = perf_config_bool(var, value);
133 	if (same_cmd_with_prefix(var, c, "gtk."))
134 		c->val = perf_config_bool(var, value) ? 2 : 0;
135 	return 0;
136 }
137 
138 /*
139  * returns 0 for "no tui", 1 for "use tui", 2 for "use gtk",
140  * and -1 for "not specified"
141  */
142 static int check_browser_config(const char *cmd)
143 {
144 	int err;
145 	struct pager_config c;
146 	c.cmd = cmd;
147 	c.val = -1;
148 	err = perf_config(browser_command_config, &c);
149 	return err ?: c.val;
150 }
151 
152 static void commit_pager_choice(void)
153 {
154 	switch (use_pager) {
155 	case 0:
156 		setenv(PERF_PAGER_ENVIRONMENT, "cat", 1);
157 		break;
158 	case 1:
159 		/* setup_pager(); */
160 		break;
161 	default:
162 		break;
163 	}
164 }
165 
166 struct option options[] = {
167 	OPT_ARGUMENT("help", "help"),
168 	OPT_ARGUMENT("version", "version"),
169 	OPT_ARGUMENT("exec-path", "exec-path"),
170 	OPT_ARGUMENT("html-path", "html-path"),
171 	OPT_ARGUMENT("paginate", "paginate"),
172 	OPT_ARGUMENT("no-pager", "no-pager"),
173 	OPT_ARGUMENT("debugfs-dir", "debugfs-dir"),
174 	OPT_ARGUMENT("buildid-dir", "buildid-dir"),
175 	OPT_ARGUMENT("list-cmds", "list-cmds"),
176 	OPT_ARGUMENT("list-opts", "list-opts"),
177 	OPT_ARGUMENT("debug", "debug"),
178 	OPT_END()
179 };
180 
181 static int handle_options(const char ***argv, int *argc, int *envchanged)
182 {
183 	int handled = 0;
184 
185 	while (*argc > 0) {
186 		const char *cmd = (*argv)[0];
187 		if (cmd[0] != '-')
188 			break;
189 
190 		/*
191 		 * For legacy reasons, the "version" and "help"
192 		 * commands can be written with "--" prepended
193 		 * to make them look like flags.
194 		 */
195 		if (!strcmp(cmd, "--help") || !strcmp(cmd, "--version"))
196 			break;
197 
198 		/*
199 		 * Shortcut for '-h' and '-v' options to invoke help
200 		 * and version command.
201 		 */
202 		if (!strcmp(cmd, "-h")) {
203 			(*argv)[0] = "--help";
204 			break;
205 		}
206 
207 		if (!strcmp(cmd, "-v")) {
208 			(*argv)[0] = "--version";
209 			break;
210 		}
211 
212 		if (!strcmp(cmd, "-vv")) {
213 			(*argv)[0] = "version";
214 			verbose = 1;
215 			break;
216 		}
217 
218 		/*
219 		 * Check remaining flags.
220 		 */
221 		if (strstarts(cmd, CMD_EXEC_PATH)) {
222 			cmd += strlen(CMD_EXEC_PATH);
223 			if (*cmd == '=')
224 				set_argv_exec_path(cmd + 1);
225 			else {
226 				puts(get_argv_exec_path());
227 				exit(0);
228 			}
229 		} else if (!strcmp(cmd, "--html-path")) {
230 			puts(system_path(PERF_HTML_PATH));
231 			exit(0);
232 		} else if (!strcmp(cmd, "-p") || !strcmp(cmd, "--paginate")) {
233 			use_pager = 1;
234 		} else if (!strcmp(cmd, "--no-pager")) {
235 			use_pager = 0;
236 			if (envchanged)
237 				*envchanged = 1;
238 		} else if (!strcmp(cmd, "--debugfs-dir")) {
239 			if (*argc < 2) {
240 				fprintf(stderr, "No directory given for --debugfs-dir.\n");
241 				usage(perf_usage_string);
242 			}
243 			tracing_path_set((*argv)[1]);
244 			if (envchanged)
245 				*envchanged = 1;
246 			(*argv)++;
247 			(*argc)--;
248 		} else if (!strcmp(cmd, "--buildid-dir")) {
249 			if (*argc < 2) {
250 				fprintf(stderr, "No directory given for --buildid-dir.\n");
251 				usage(perf_usage_string);
252 			}
253 			set_buildid_dir((*argv)[1]);
254 			if (envchanged)
255 				*envchanged = 1;
256 			(*argv)++;
257 			(*argc)--;
258 		} else if (strstarts(cmd, CMD_DEBUGFS_DIR)) {
259 			tracing_path_set(cmd + strlen(CMD_DEBUGFS_DIR));
260 			fprintf(stderr, "dir: %s\n", tracing_path_mount());
261 			if (envchanged)
262 				*envchanged = 1;
263 		} else if (!strcmp(cmd, "--list-cmds")) {
264 			unsigned int i;
265 
266 			for (i = 0; i < ARRAY_SIZE(commands); i++) {
267 				struct cmd_struct *p = commands+i;
268 				printf("%s ", p->cmd);
269 			}
270 			putchar('\n');
271 			exit(0);
272 		} else if (!strcmp(cmd, "--list-opts")) {
273 			unsigned int i;
274 
275 			for (i = 0; i < ARRAY_SIZE(options)-1; i++) {
276 				struct option *p = options+i;
277 				printf("--%s ", p->long_name);
278 			}
279 			putchar('\n');
280 			exit(0);
281 		} else if (!strcmp(cmd, "--debug")) {
282 			if (*argc < 2) {
283 				fprintf(stderr, "No variable specified for --debug.\n");
284 				usage(perf_usage_string);
285 			}
286 			if (perf_debug_option((*argv)[1]))
287 				usage(perf_usage_string);
288 
289 			(*argv)++;
290 			(*argc)--;
291 		} else {
292 			fprintf(stderr, "Unknown option: %s\n", cmd);
293 			usage(perf_usage_string);
294 		}
295 
296 		(*argv)++;
297 		(*argc)--;
298 		handled++;
299 	}
300 	return handled;
301 }
302 
303 #define RUN_SETUP	(1<<0)
304 #define USE_PAGER	(1<<1)
305 
306 static int run_builtin(struct cmd_struct *p, int argc, const char **argv)
307 {
308 	int status;
309 	struct stat st;
310 	char sbuf[STRERR_BUFSIZE];
311 
312 	if (use_browser == -1)
313 		use_browser = check_browser_config(p->cmd);
314 
315 	if (use_pager == -1 && p->option & RUN_SETUP)
316 		use_pager = check_pager_config(p->cmd);
317 	if (use_pager == -1 && p->option & USE_PAGER)
318 		use_pager = 1;
319 	commit_pager_choice();
320 
321 	perf_env__init(&perf_env);
322 	perf_env__set_cmdline(&perf_env, argc, argv);
323 	status = p->fn(argc, argv);
324 	perf_config__exit();
325 	exit_browser(status);
326 	perf_env__exit(&perf_env);
327 	bpf__clear();
328 
329 	if (status)
330 		return status & 0xff;
331 
332 	/* Somebody closed stdout? */
333 	if (fstat(fileno(stdout), &st))
334 		return 0;
335 	/* Ignore write errors for pipes and sockets.. */
336 	if (S_ISFIFO(st.st_mode) || S_ISSOCK(st.st_mode))
337 		return 0;
338 
339 	status = 1;
340 	/* Check for ENOSPC and EIO errors.. */
341 	if (fflush(stdout)) {
342 		fprintf(stderr, "write failure on standard output: %s",
343 			str_error_r(errno, sbuf, sizeof(sbuf)));
344 		goto out;
345 	}
346 	if (ferror(stdout)) {
347 		fprintf(stderr, "unknown write failure on standard output");
348 		goto out;
349 	}
350 	if (fclose(stdout)) {
351 		fprintf(stderr, "close failed on standard output: %s",
352 			str_error_r(errno, sbuf, sizeof(sbuf)));
353 		goto out;
354 	}
355 	status = 0;
356 out:
357 	return status;
358 }
359 
360 static void handle_internal_command(int argc, const char **argv)
361 {
362 	const char *cmd = argv[0];
363 	unsigned int i;
364 
365 	/* Turn "perf cmd --help" into "perf help cmd" */
366 	if (argc > 1 && !strcmp(argv[1], "--help")) {
367 		argv[1] = argv[0];
368 		argv[0] = cmd = "help";
369 	}
370 
371 	for (i = 0; i < ARRAY_SIZE(commands); i++) {
372 		struct cmd_struct *p = commands+i;
373 		if (p->fn == NULL)
374 			continue;
375 		if (strcmp(p->cmd, cmd))
376 			continue;
377 		exit(run_builtin(p, argc, argv));
378 	}
379 }
380 
381 static void execv_dashed_external(const char **argv)
382 {
383 	char *cmd;
384 	const char *tmp;
385 	int status;
386 
387 	if (asprintf(&cmd, "perf-%s", argv[0]) < 0)
388 		goto do_die;
389 
390 	/*
391 	 * argv[0] must be the perf command, but the argv array
392 	 * belongs to the caller, and may be reused in
393 	 * subsequent loop iterations. Save argv[0] and
394 	 * restore it on error.
395 	 */
396 	tmp = argv[0];
397 	argv[0] = cmd;
398 
399 	/*
400 	 * if we fail because the command is not found, it is
401 	 * OK to return. Otherwise, we just pass along the status code.
402 	 */
403 	status = run_command_v_opt(argv, 0);
404 	if (status != -ERR_RUN_COMMAND_EXEC) {
405 		if (IS_RUN_COMMAND_ERR(status)) {
406 do_die:
407 			pr_err("FATAL: unable to run '%s'", argv[0]);
408 			status = -128;
409 		}
410 		exit(-status);
411 	}
412 	errno = ENOENT; /* as if we called execvp */
413 
414 	argv[0] = tmp;
415 	zfree(&cmd);
416 }
417 
418 static int run_argv(int *argcp, const char ***argv)
419 {
420 	/* See if it's an internal command */
421 	handle_internal_command(*argcp, *argv);
422 
423 	/* .. then try the external ones */
424 	execv_dashed_external(*argv);
425 	return 0;
426 }
427 
428 static int libperf_print(enum libperf_print_level level,
429 			 const char *fmt, va_list ap)
430 {
431 	return veprintf(level, verbose, fmt, ap);
432 }
433 
434 int main(int argc, const char **argv)
435 {
436 	int err;
437 	const char *cmd;
438 	char sbuf[STRERR_BUFSIZE];
439 
440 	perf_debug_setup();
441 
442 	/* libsubcmd init */
443 	exec_cmd_init("perf", PREFIX, PERF_EXEC_PATH, EXEC_PATH_ENVIRONMENT);
444 	pager_init(PERF_PAGER_ENVIRONMENT);
445 
446 	libperf_init(libperf_print);
447 
448 	cmd = extract_argv0_path(argv[0]);
449 	if (!cmd)
450 		cmd = "perf-help";
451 
452 	srandom(time(NULL));
453 
454 	/* Setting $PERF_CONFIG makes perf read _only_ the given config file. */
455 	config_exclusive_filename = getenv("PERF_CONFIG");
456 
457 	err = perf_config(perf_default_config, NULL);
458 	if (err)
459 		return err;
460 	set_buildid_dir(NULL);
461 
462 	/*
463 	 * "perf-xxxx" is the same as "perf xxxx", but we obviously:
464 	 *
465 	 *  - cannot take flags in between the "perf" and the "xxxx".
466 	 *  - cannot execute it externally (since it would just do
467 	 *    the same thing over again)
468 	 *
469 	 * So we just directly call the internal command handler. If that one
470 	 * fails to handle this, then maybe we just run a renamed perf binary
471 	 * that contains a dash in its name. To handle this scenario, we just
472 	 * fall through and ignore the "xxxx" part of the command string.
473 	 */
474 	if (strstarts(cmd, "perf-")) {
475 		cmd += 5;
476 		argv[0] = cmd;
477 		handle_internal_command(argc, argv);
478 		/*
479 		 * If the command is handled, the above function does not
480 		 * return undo changes and fall through in such a case.
481 		 */
482 		cmd -= 5;
483 		argv[0] = cmd;
484 	}
485 	if (strstarts(cmd, "trace")) {
486 #ifndef HAVE_LIBTRACEEVENT
487 		fprintf(stderr,
488 			"trace command not available: missing libtraceevent devel package at build time.\n");
489 		goto out;
490 #elif !defined(HAVE_LIBAUDIT_SUPPORT) && !defined(HAVE_SYSCALL_TABLE_SUPPORT)
491 		fprintf(stderr,
492 			"trace command not available: missing audit-libs devel package at build time.\n");
493 		goto out;
494 #else
495 		setup_path();
496 		argv[0] = "trace";
497 		return cmd_trace(argc, argv);
498 #endif
499 	}
500 	/* Look for flags.. */
501 	argv++;
502 	argc--;
503 	handle_options(&argv, &argc, NULL);
504 	commit_pager_choice();
505 
506 	if (argc > 0) {
507 		if (strstarts(argv[0], "--"))
508 			argv[0] += 2;
509 	} else {
510 		/* The user didn't specify a command; give them help */
511 		printf("\n usage: %s\n\n", perf_usage_string);
512 		list_common_cmds_help();
513 		printf("\n %s\n\n", perf_more_info_string);
514 		goto out;
515 	}
516 	cmd = argv[0];
517 
518 	test_attr__init();
519 
520 	/*
521 	 * We use PATH to find perf commands, but we prepend some higher
522 	 * precedence paths: the "--exec-path" option, the PERF_EXEC_PATH
523 	 * environment, and the $(perfexecdir) from the Makefile at build
524 	 * time.
525 	 */
526 	setup_path();
527 	/*
528 	 * Block SIGWINCH notifications so that the thread that wants it can
529 	 * unblock and get syscalls like select interrupted instead of waiting
530 	 * forever while the signal goes to some other non interested thread.
531 	 */
532 	pthread__block_sigwinch();
533 
534 	while (1) {
535 		static int done_help;
536 
537 		run_argv(&argc, &argv);
538 
539 		if (errno != ENOENT)
540 			break;
541 
542 		if (!done_help) {
543 			cmd = argv[0] = help_unknown_cmd(cmd);
544 			done_help = 1;
545 		} else
546 			break;
547 	}
548 
549 	fprintf(stderr, "Failed to run command '%s': %s\n",
550 		cmd, str_error_r(errno, sbuf, sizeof(sbuf)));
551 out:
552 	return 1;
553 }
554