xref: /openbmc/linux/tools/perf/perf.c (revision 5a244f48) 
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 
11 #include "util/env.h"
12 #include <subcmd/exec-cmd.h>
13 #include "util/config.h"
14 #include "util/quote.h"
15 #include <subcmd/run-command.h>
16 #include "util/parse-events.h"
17 #include <subcmd/parse-options.h>
18 #include "util/bpf-loader.h"
19 #include "util/debug.h"
20 #include "util/event.h"
21 #include <api/fs/fs.h>
22 #include <api/fs/tracing_path.h>
23 #include <errno.h>
24 #include <pthread.h>
25 #include <signal.h>
26 #include <stdlib.h>
27 #include <time.h>
28 #include <sys/types.h>
29 #include <sys/stat.h>
30 #include <unistd.h>
31 #include <linux/kernel.h>
32 
33 const char perf_usage_string[] =
34 	"perf [--version] [--help] [OPTIONS] COMMAND [ARGS]";
35 
36 const char perf_more_info_string[] =
37 	"See 'perf help COMMAND' for more information on a specific command.";
38 
39 static int use_pager = -1;
40 const char *input_name;
41 
42 struct cmd_struct {
43 	const char *cmd;
44 	int (*fn)(int, const char **);
45 	int option;
46 };
47 
48 static struct cmd_struct commands[] = {
49 	{ "buildid-cache", cmd_buildid_cache, 0 },
50 	{ "buildid-list", cmd_buildid_list, 0 },
51 	{ "config",	cmd_config,	0 },
52 	{ "c2c",	cmd_c2c,	0 },
53 	{ "diff",	cmd_diff,	0 },
54 	{ "evlist",	cmd_evlist,	0 },
55 	{ "help",	cmd_help,	0 },
56 	{ "kallsyms",	cmd_kallsyms,	0 },
57 	{ "list",	cmd_list,	0 },
58 	{ "record",	cmd_record,	0 },
59 	{ "report",	cmd_report,	0 },
60 	{ "bench",	cmd_bench,	0 },
61 	{ "stat",	cmd_stat,	0 },
62 	{ "timechart",	cmd_timechart,	0 },
63 	{ "top",	cmd_top,	0 },
64 	{ "annotate",	cmd_annotate,	0 },
65 	{ "version",	cmd_version,	0 },
66 	{ "script",	cmd_script,	0 },
67 	{ "sched",	cmd_sched,	0 },
68 #ifdef HAVE_LIBELF_SUPPORT
69 	{ "probe",	cmd_probe,	0 },
70 #endif
71 	{ "kmem",	cmd_kmem,	0 },
72 	{ "lock",	cmd_lock,	0 },
73 	{ "kvm",	cmd_kvm,	0 },
74 	{ "test",	cmd_test,	0 },
75 #ifdef HAVE_LIBAUDIT_SUPPORT
76 	{ "trace",	cmd_trace,	0 },
77 #endif
78 	{ "inject",	cmd_inject,	0 },
79 	{ "mem",	cmd_mem,	0 },
80 	{ "data",	cmd_data,	0 },
81 	{ "ftrace",	cmd_ftrace,	0 },
82 };
83 
84 struct pager_config {
85 	const char *cmd;
86 	int val;
87 };
88 
89 static int pager_command_config(const char *var, const char *value, void *data)
90 {
91 	struct pager_config *c = data;
92 	if (strstarts(var, "pager.") && !strcmp(var + 6, c->cmd))
93 		c->val = perf_config_bool(var, value);
94 	return 0;
95 }
96 
97 /* returns 0 for "no pager", 1 for "use pager", and -1 for "not specified" */
98 static int check_pager_config(const char *cmd)
99 {
100 	int err;
101 	struct pager_config c;
102 	c.cmd = cmd;
103 	c.val = -1;
104 	err = perf_config(pager_command_config, &c);
105 	return err ?: c.val;
106 }
107 
108 static int browser_command_config(const char *var, const char *value, void *data)
109 {
110 	struct pager_config *c = data;
111 	if (strstarts(var, "tui.") && !strcmp(var + 4, c->cmd))
112 		c->val = perf_config_bool(var, value);
113 	if (strstarts(var, "gtk.") && !strcmp(var + 4, c->cmd))
114 		c->val = perf_config_bool(var, value) ? 2 : 0;
115 	return 0;
116 }
117 
118 /*
119  * returns 0 for "no tui", 1 for "use tui", 2 for "use gtk",
120  * and -1 for "not specified"
121  */
122 static int check_browser_config(const char *cmd)
123 {
124 	int err;
125 	struct pager_config c;
126 	c.cmd = cmd;
127 	c.val = -1;
128 	err = perf_config(browser_command_config, &c);
129 	return err ?: c.val;
130 }
131 
132 static void commit_pager_choice(void)
133 {
134 	switch (use_pager) {
135 	case 0:
136 		setenv(PERF_PAGER_ENVIRONMENT, "cat", 1);
137 		break;
138 	case 1:
139 		/* setup_pager(); */
140 		break;
141 	default:
142 		break;
143 	}
144 }
145 
146 struct option options[] = {
147 	OPT_ARGUMENT("help", "help"),
148 	OPT_ARGUMENT("version", "version"),
149 	OPT_ARGUMENT("exec-path", "exec-path"),
150 	OPT_ARGUMENT("html-path", "html-path"),
151 	OPT_ARGUMENT("paginate", "paginate"),
152 	OPT_ARGUMENT("no-pager", "no-pager"),
153 	OPT_ARGUMENT("debugfs-dir", "debugfs-dir"),
154 	OPT_ARGUMENT("buildid-dir", "buildid-dir"),
155 	OPT_ARGUMENT("list-cmds", "list-cmds"),
156 	OPT_ARGUMENT("list-opts", "list-opts"),
157 	OPT_ARGUMENT("debug", "debug"),
158 	OPT_END()
159 };
160 
161 static int handle_options(const char ***argv, int *argc, int *envchanged)
162 {
163 	int handled = 0;
164 
165 	while (*argc > 0) {
166 		const char *cmd = (*argv)[0];
167 		if (cmd[0] != '-')
168 			break;
169 
170 		/*
171 		 * For legacy reasons, the "version" and "help"
172 		 * commands can be written with "--" prepended
173 		 * to make them look like flags.
174 		 */
175 		if (!strcmp(cmd, "--help") || !strcmp(cmd, "--version"))
176 			break;
177 
178 		/*
179 		 * Shortcut for '-h' and '-v' options to invoke help
180 		 * and version command.
181 		 */
182 		if (!strcmp(cmd, "-h")) {
183 			(*argv)[0] = "--help";
184 			break;
185 		}
186 
187 		if (!strcmp(cmd, "-v")) {
188 			(*argv)[0] = "--version";
189 			break;
190 		}
191 
192 		/*
193 		 * Check remaining flags.
194 		 */
195 		if (strstarts(cmd, CMD_EXEC_PATH)) {
196 			cmd += strlen(CMD_EXEC_PATH);
197 			if (*cmd == '=')
198 				set_argv_exec_path(cmd + 1);
199 			else {
200 				puts(get_argv_exec_path());
201 				exit(0);
202 			}
203 		} else if (!strcmp(cmd, "--html-path")) {
204 			puts(system_path(PERF_HTML_PATH));
205 			exit(0);
206 		} else if (!strcmp(cmd, "-p") || !strcmp(cmd, "--paginate")) {
207 			use_pager = 1;
208 		} else if (!strcmp(cmd, "--no-pager")) {
209 			use_pager = 0;
210 			if (envchanged)
211 				*envchanged = 1;
212 		} else if (!strcmp(cmd, "--debugfs-dir")) {
213 			if (*argc < 2) {
214 				fprintf(stderr, "No directory given for --debugfs-dir.\n");
215 				usage(perf_usage_string);
216 			}
217 			tracing_path_set((*argv)[1]);
218 			if (envchanged)
219 				*envchanged = 1;
220 			(*argv)++;
221 			(*argc)--;
222 		} else if (!strcmp(cmd, "--buildid-dir")) {
223 			if (*argc < 2) {
224 				fprintf(stderr, "No directory given for --buildid-dir.\n");
225 				usage(perf_usage_string);
226 			}
227 			set_buildid_dir((*argv)[1]);
228 			if (envchanged)
229 				*envchanged = 1;
230 			(*argv)++;
231 			(*argc)--;
232 		} else if (strstarts(cmd, CMD_DEBUGFS_DIR)) {
233 			tracing_path_set(cmd + strlen(CMD_DEBUGFS_DIR));
234 			fprintf(stderr, "dir: %s\n", tracing_path);
235 			if (envchanged)
236 				*envchanged = 1;
237 		} else if (!strcmp(cmd, "--list-cmds")) {
238 			unsigned int i;
239 
240 			for (i = 0; i < ARRAY_SIZE(commands); i++) {
241 				struct cmd_struct *p = commands+i;
242 				printf("%s ", p->cmd);
243 			}
244 			putchar('\n');
245 			exit(0);
246 		} else if (!strcmp(cmd, "--list-opts")) {
247 			unsigned int i;
248 
249 			for (i = 0; i < ARRAY_SIZE(options)-1; i++) {
250 				struct option *p = options+i;
251 				printf("--%s ", p->long_name);
252 			}
253 			putchar('\n');
254 			exit(0);
255 		} else if (!strcmp(cmd, "--debug")) {
256 			if (*argc < 2) {
257 				fprintf(stderr, "No variable specified for --debug.\n");
258 				usage(perf_usage_string);
259 			}
260 			if (perf_debug_option((*argv)[1]))
261 				usage(perf_usage_string);
262 
263 			(*argv)++;
264 			(*argc)--;
265 		} else {
266 			fprintf(stderr, "Unknown option: %s\n", cmd);
267 			usage(perf_usage_string);
268 		}
269 
270 		(*argv)++;
271 		(*argc)--;
272 		handled++;
273 	}
274 	return handled;
275 }
276 
277 #define RUN_SETUP	(1<<0)
278 #define USE_PAGER	(1<<1)
279 
280 static int run_builtin(struct cmd_struct *p, int argc, const char **argv)
281 {
282 	int status;
283 	struct stat st;
284 	char sbuf[STRERR_BUFSIZE];
285 
286 	if (use_browser == -1)
287 		use_browser = check_browser_config(p->cmd);
288 
289 	if (use_pager == -1 && p->option & RUN_SETUP)
290 		use_pager = check_pager_config(p->cmd);
291 	if (use_pager == -1 && p->option & USE_PAGER)
292 		use_pager = 1;
293 	commit_pager_choice();
294 
295 	perf_env__set_cmdline(&perf_env, argc, argv);
296 	status = p->fn(argc, argv);
297 	perf_config__exit();
298 	exit_browser(status);
299 	perf_env__exit(&perf_env);
300 	bpf__clear();
301 
302 	if (status)
303 		return status & 0xff;
304 
305 	/* Somebody closed stdout? */
306 	if (fstat(fileno(stdout), &st))
307 		return 0;
308 	/* Ignore write errors for pipes and sockets.. */
309 	if (S_ISFIFO(st.st_mode) || S_ISSOCK(st.st_mode))
310 		return 0;
311 
312 	status = 1;
313 	/* Check for ENOSPC and EIO errors.. */
314 	if (fflush(stdout)) {
315 		fprintf(stderr, "write failure on standard output: %s",
316 			str_error_r(errno, sbuf, sizeof(sbuf)));
317 		goto out;
318 	}
319 	if (ferror(stdout)) {
320 		fprintf(stderr, "unknown write failure on standard output");
321 		goto out;
322 	}
323 	if (fclose(stdout)) {
324 		fprintf(stderr, "close failed on standard output: %s",
325 			str_error_r(errno, sbuf, sizeof(sbuf)));
326 		goto out;
327 	}
328 	status = 0;
329 out:
330 	return status;
331 }
332 
333 static void handle_internal_command(int argc, const char **argv)
334 {
335 	const char *cmd = argv[0];
336 	unsigned int i;
337 
338 	/* Turn "perf cmd --help" into "perf help cmd" */
339 	if (argc > 1 && !strcmp(argv[1], "--help")) {
340 		argv[1] = argv[0];
341 		argv[0] = cmd = "help";
342 	}
343 
344 	for (i = 0; i < ARRAY_SIZE(commands); i++) {
345 		struct cmd_struct *p = commands+i;
346 		if (strcmp(p->cmd, cmd))
347 			continue;
348 		exit(run_builtin(p, argc, argv));
349 	}
350 }
351 
352 static void execv_dashed_external(const char **argv)
353 {
354 	char *cmd;
355 	const char *tmp;
356 	int status;
357 
358 	if (asprintf(&cmd, "perf-%s", argv[0]) < 0)
359 		goto do_die;
360 
361 	/*
362 	 * argv[0] must be the perf command, but the argv array
363 	 * belongs to the caller, and may be reused in
364 	 * subsequent loop iterations. Save argv[0] and
365 	 * restore it on error.
366 	 */
367 	tmp = argv[0];
368 	argv[0] = cmd;
369 
370 	/*
371 	 * if we fail because the command is not found, it is
372 	 * OK to return. Otherwise, we just pass along the status code.
373 	 */
374 	status = run_command_v_opt(argv, 0);
375 	if (status != -ERR_RUN_COMMAND_EXEC) {
376 		if (IS_RUN_COMMAND_ERR(status)) {
377 do_die:
378 			pr_err("FATAL: unable to run '%s'", argv[0]);
379 			status = -128;
380 		}
381 		exit(-status);
382 	}
383 	errno = ENOENT; /* as if we called execvp */
384 
385 	argv[0] = tmp;
386 	zfree(&cmd);
387 }
388 
389 static int run_argv(int *argcp, const char ***argv)
390 {
391 	/* See if it's an internal command */
392 	handle_internal_command(*argcp, *argv);
393 
394 	/* .. then try the external ones */
395 	execv_dashed_external(*argv);
396 	return 0;
397 }
398 
399 static void pthread__block_sigwinch(void)
400 {
401 	sigset_t set;
402 
403 	sigemptyset(&set);
404 	sigaddset(&set, SIGWINCH);
405 	pthread_sigmask(SIG_BLOCK, &set, NULL);
406 }
407 
408 void pthread__unblock_sigwinch(void)
409 {
410 	sigset_t set;
411 
412 	sigemptyset(&set);
413 	sigaddset(&set, SIGWINCH);
414 	pthread_sigmask(SIG_UNBLOCK, &set, NULL);
415 }
416 
417 #ifdef _SC_LEVEL1_DCACHE_LINESIZE
418 #define cache_line_size(cacheline_sizep) *cacheline_sizep = sysconf(_SC_LEVEL1_DCACHE_LINESIZE)
419 #else
420 static void cache_line_size(int *cacheline_sizep)
421 {
422 	if (sysfs__read_int("devices/system/cpu/cpu0/cache/index0/coherency_line_size", cacheline_sizep))
423 		pr_debug("cannot determine cache line size");
424 }
425 #endif
426 
427 int main(int argc, const char **argv)
428 {
429 	int err;
430 	const char *cmd;
431 	char sbuf[STRERR_BUFSIZE];
432 	int value;
433 
434 	/* libsubcmd init */
435 	exec_cmd_init("perf", PREFIX, PERF_EXEC_PATH, EXEC_PATH_ENVIRONMENT);
436 	pager_init(PERF_PAGER_ENVIRONMENT);
437 
438 	/* The page_size is placed in util object. */
439 	page_size = sysconf(_SC_PAGE_SIZE);
440 	cache_line_size(&cacheline_size);
441 
442 	if (sysctl__read_int("kernel/perf_event_max_stack", &value) == 0)
443 		sysctl_perf_event_max_stack = value;
444 
445 	if (sysctl__read_int("kernel/perf_event_max_contexts_per_stack", &value) == 0)
446 		sysctl_perf_event_max_contexts_per_stack = value;
447 
448 	cmd = extract_argv0_path(argv[0]);
449 	if (!cmd)
450 		cmd = "perf-help";
451 
452 	srandom(time(NULL));
453 
454 	perf_config__init();
455 	err = perf_config(perf_default_config, NULL);
456 	if (err)
457 		return err;
458 	set_buildid_dir(NULL);
459 
460 	/* get debugfs/tracefs mount point from /proc/mounts */
461 	tracing_path_mount();
462 
463 	/*
464 	 * "perf-xxxx" is the same as "perf xxxx", but we obviously:
465 	 *
466 	 *  - cannot take flags in between the "perf" and the "xxxx".
467 	 *  - cannot execute it externally (since it would just do
468 	 *    the same thing over again)
469 	 *
470 	 * So we just directly call the internal command handler. If that one
471 	 * fails to handle this, then maybe we just run a renamed perf binary
472 	 * that contains a dash in its name. To handle this scenario, we just
473 	 * fall through and ignore the "xxxx" part of the command string.
474 	 */
475 	if (strstarts(cmd, "perf-")) {
476 		cmd += 5;
477 		argv[0] = cmd;
478 		handle_internal_command(argc, argv);
479 		/*
480 		 * If the command is handled, the above function does not
481 		 * return undo changes and fall through in such a case.
482 		 */
483 		cmd -= 5;
484 		argv[0] = cmd;
485 	}
486 	if (strstarts(cmd, "trace")) {
487 #ifdef HAVE_LIBAUDIT_SUPPORT
488 		setup_path();
489 		argv[0] = "trace";
490 		return cmd_trace(argc, argv);
491 #else
492 		fprintf(stderr,
493 			"trace command not available: missing audit-libs devel package at build time.\n");
494 		goto out;
495 #endif
496 	}
497 	/* Look for flags.. */
498 	argv++;
499 	argc--;
500 	handle_options(&argv, &argc, NULL);
501 	commit_pager_choice();
502 
503 	if (argc > 0) {
504 		if (strstarts(argv[0], "--"))
505 			argv[0] += 2;
506 	} else {
507 		/* The user didn't specify a command; give them help */
508 		printf("\n usage: %s\n\n", perf_usage_string);
509 		list_common_cmds_help();
510 		printf("\n %s\n\n", perf_more_info_string);
511 		goto out;
512 	}
513 	cmd = argv[0];
514 
515 	test_attr__init();
516 
517 	/*
518 	 * We use PATH to find perf commands, but we prepend some higher
519 	 * precedence paths: the "--exec-path" option, the PERF_EXEC_PATH
520 	 * environment, and the $(perfexecdir) from the Makefile at build
521 	 * time.
522 	 */
523 	setup_path();
524 	/*
525 	 * Block SIGWINCH notifications so that the thread that wants it can
526 	 * unblock and get syscalls like select interrupted instead of waiting
527 	 * forever while the signal goes to some other non interested thread.
528 	 */
529 	pthread__block_sigwinch();
530 
531 	perf_debug_setup();
532 
533 	while (1) {
534 		static int done_help;
535 
536 		run_argv(&argc, &argv);
537 
538 		if (errno != ENOENT)
539 			break;
540 
541 		if (!done_help) {
542 			cmd = argv[0] = help_unknown_cmd(cmd);
543 			done_help = 1;
544 		} else
545 			break;
546 	}
547 
548 	fprintf(stderr, "Failed to run command '%s': %s\n",
549 		cmd, str_error_r(errno, sbuf, sizeof(sbuf)));
550 out:
551 	return 1;
552 }
553