xref: /kernel/linux/linux-6.6/tools/perf/perf.c (revision 62306a36) 
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/debug.h"
22#include "util/event.h"
23#include "util/util.h" // usage()
24#include "ui/ui.h"
25#include "perf-sys.h"
26#include <api/fs/fs.h>
27#include <api/fs/tracing_path.h>
28#include <perf/core.h>
29#include <errno.h>
30#include <pthread.h>
31#include <signal.h>
32#include <stdlib.h>
33#include <time.h>
34#include <sys/types.h>
35#include <sys/stat.h>
36#include <unistd.h>
37#include <linux/kernel.h>
38#include <linux/string.h>
39#include <linux/zalloc.h>
40
41static int use_pager = -1;
42
43struct cmd_struct {
44	const char *cmd;
45	int (*fn)(int, const char **);
46	int option;
47};
48
49static struct cmd_struct commands[] = {
50	{ "archive",	NULL,	0 },
51	{ "buildid-cache", cmd_buildid_cache, 0 },
52	{ "buildid-list", cmd_buildid_list, 0 },
53	{ "config",	cmd_config,	0 },
54	{ "c2c",	cmd_c2c,	0 },
55	{ "diff",	cmd_diff,	0 },
56	{ "evlist",	cmd_evlist,	0 },
57	{ "help",	cmd_help,	0 },
58	{ "iostat",	NULL,	0 },
59	{ "kallsyms",	cmd_kallsyms,	0 },
60	{ "list",	cmd_list,	0 },
61	{ "record",	cmd_record,	0 },
62	{ "report",	cmd_report,	0 },
63	{ "bench",	cmd_bench,	0 },
64	{ "stat",	cmd_stat,	0 },
65#ifdef HAVE_LIBTRACEEVENT
66	{ "timechart",	cmd_timechart,	0 },
67#endif
68	{ "top",	cmd_top,	0 },
69	{ "annotate",	cmd_annotate,	0 },
70	{ "version",	cmd_version,	0 },
71	{ "script",	cmd_script,	0 },
72#ifdef HAVE_LIBTRACEEVENT
73	{ "sched",	cmd_sched,	0 },
74#endif
75#ifdef HAVE_LIBELF_SUPPORT
76	{ "probe",	cmd_probe,	0 },
77#endif
78#ifdef HAVE_LIBTRACEEVENT
79	{ "kmem",	cmd_kmem,	0 },
80	{ "lock",	cmd_lock,	0 },
81#endif
82	{ "kvm",	cmd_kvm,	0 },
83	{ "test",	cmd_test,	0 },
84#if defined(HAVE_LIBTRACEEVENT) && (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#ifdef HAVE_LIBTRACEEVENT
93	{ "kwork",	cmd_kwork,	0 },
94#endif
95};
96
97struct pager_config {
98	const char *cmd;
99	int val;
100};
101
102static bool same_cmd_with_prefix(const char *var, struct pager_config *c,
103				  const char *header)
104{
105	return (strstarts(var, header) && !strcmp(var + strlen(header), c->cmd));
106}
107
108static int pager_command_config(const char *var, const char *value, void *data)
109{
110	struct pager_config *c = data;
111	if (same_cmd_with_prefix(var, c, "pager."))
112		c->val = perf_config_bool(var, value);
113	return 0;
114}
115
116/* returns 0 for "no pager", 1 for "use pager", and -1 for "not specified" */
117static int check_pager_config(const char *cmd)
118{
119	int err;
120	struct pager_config c;
121	c.cmd = cmd;
122	c.val = -1;
123	err = perf_config(pager_command_config, &c);
124	return err ?: c.val;
125}
126
127static int browser_command_config(const char *var, const char *value, void *data)
128{
129	struct pager_config *c = data;
130	if (same_cmd_with_prefix(var, c, "tui."))
131		c->val = perf_config_bool(var, value);
132	if (same_cmd_with_prefix(var, c, "gtk."))
133		c->val = perf_config_bool(var, value) ? 2 : 0;
134	return 0;
135}
136
137/*
138 * returns 0 for "no tui", 1 for "use tui", 2 for "use gtk",
139 * and -1 for "not specified"
140 */
141static int check_browser_config(const char *cmd)
142{
143	int err;
144	struct pager_config c;
145	c.cmd = cmd;
146	c.val = -1;
147	err = perf_config(browser_command_config, &c);
148	return err ?: c.val;
149}
150
151static void commit_pager_choice(void)
152{
153	switch (use_pager) {
154	case 0:
155		setenv(PERF_PAGER_ENVIRONMENT, "cat", 1);
156		break;
157	case 1:
158		/* setup_pager(); */
159		break;
160	default:
161		break;
162	}
163}
164
165struct option options[] = {
166	OPT_ARGUMENT("help", "help"),
167	OPT_ARGUMENT("version", "version"),
168	OPT_ARGUMENT("exec-path", "exec-path"),
169	OPT_ARGUMENT("html-path", "html-path"),
170	OPT_ARGUMENT("paginate", "paginate"),
171	OPT_ARGUMENT("no-pager", "no-pager"),
172	OPT_ARGUMENT("debugfs-dir", "debugfs-dir"),
173	OPT_ARGUMENT("buildid-dir", "buildid-dir"),
174	OPT_ARGUMENT("list-cmds", "list-cmds"),
175	OPT_ARGUMENT("list-opts", "list-opts"),
176	OPT_ARGUMENT("debug", "debug"),
177	OPT_END()
178};
179
180static int handle_options(const char ***argv, int *argc, int *envchanged)
181{
182	int handled = 0;
183
184	while (*argc > 0) {
185		const char *cmd = (*argv)[0];
186		if (cmd[0] != '-')
187			break;
188
189		/*
190		 * For legacy reasons, the "version" and "help"
191		 * commands can be written with "--" prepended
192		 * to make them look like flags.
193		 */
194		if (!strcmp(cmd, "--help") || !strcmp(cmd, "--version"))
195			break;
196
197		/*
198		 * Shortcut for '-h' and '-v' options to invoke help
199		 * and version command.
200		 */
201		if (!strcmp(cmd, "-h")) {
202			(*argv)[0] = "--help";
203			break;
204		}
205
206		if (!strcmp(cmd, "-v")) {
207			(*argv)[0] = "--version";
208			break;
209		}
210
211		if (!strcmp(cmd, "-vv")) {
212			(*argv)[0] = "version";
213			verbose = 1;
214			break;
215		}
216
217		/*
218		 * Check remaining flags.
219		 */
220		if (strstarts(cmd, CMD_EXEC_PATH)) {
221			cmd += strlen(CMD_EXEC_PATH);
222			if (*cmd == '=')
223				set_argv_exec_path(cmd + 1);
224			else {
225				puts(get_argv_exec_path());
226				exit(0);
227			}
228		} else if (!strcmp(cmd, "--html-path")) {
229			puts(system_path(PERF_HTML_PATH));
230			exit(0);
231		} else if (!strcmp(cmd, "-p") || !strcmp(cmd, "--paginate")) {
232			use_pager = 1;
233		} else if (!strcmp(cmd, "--no-pager")) {
234			use_pager = 0;
235			if (envchanged)
236				*envchanged = 1;
237		} else if (!strcmp(cmd, "--debugfs-dir")) {
238			if (*argc < 2) {
239				fprintf(stderr, "No directory given for --debugfs-dir.\n");
240				usage(perf_usage_string);
241			}
242			tracing_path_set((*argv)[1]);
243			if (envchanged)
244				*envchanged = 1;
245			(*argv)++;
246			(*argc)--;
247		} else if (!strcmp(cmd, "--buildid-dir")) {
248			if (*argc < 2) {
249				fprintf(stderr, "No directory given for --buildid-dir.\n");
250				usage(perf_usage_string);
251			}
252			set_buildid_dir((*argv)[1]);
253			if (envchanged)
254				*envchanged = 1;
255			(*argv)++;
256			(*argc)--;
257		} else if (strstarts(cmd, CMD_DEBUGFS_DIR)) {
258			tracing_path_set(cmd + strlen(CMD_DEBUGFS_DIR));
259			fprintf(stderr, "dir: %s\n", tracing_path_mount());
260			if (envchanged)
261				*envchanged = 1;
262		} else if (!strcmp(cmd, "--list-cmds")) {
263			unsigned int i;
264
265			for (i = 0; i < ARRAY_SIZE(commands); i++) {
266				struct cmd_struct *p = commands+i;
267				printf("%s ", p->cmd);
268			}
269			putchar('\n');
270			exit(0);
271		} else if (!strcmp(cmd, "--list-opts")) {
272			unsigned int i;
273
274			for (i = 0; i < ARRAY_SIZE(options)-1; i++) {
275				struct option *p = options+i;
276				printf("--%s ", p->long_name);
277			}
278			putchar('\n');
279			exit(0);
280		} else if (!strcmp(cmd, "--debug")) {
281			if (*argc < 2) {
282				fprintf(stderr, "No variable specified for --debug.\n");
283				usage(perf_usage_string);
284			}
285			if (perf_debug_option((*argv)[1]))
286				usage(perf_usage_string);
287
288			(*argv)++;
289			(*argc)--;
290		} else {
291			fprintf(stderr, "Unknown option: %s\n", cmd);
292			usage(perf_usage_string);
293		}
294
295		(*argv)++;
296		(*argc)--;
297		handled++;
298	}
299	return handled;
300}
301
302#define RUN_SETUP	(1<<0)
303#define USE_PAGER	(1<<1)
304
305static int run_builtin(struct cmd_struct *p, int argc, const char **argv)
306{
307	int status;
308	struct stat st;
309	char sbuf[STRERR_BUFSIZE];
310
311	if (use_browser == -1)
312		use_browser = check_browser_config(p->cmd);
313
314	if (use_pager == -1 && p->option & RUN_SETUP)
315		use_pager = check_pager_config(p->cmd);
316	if (use_pager == -1 && p->option & USE_PAGER)
317		use_pager = 1;
318	commit_pager_choice();
319
320	perf_env__init(&perf_env);
321	perf_env__set_cmdline(&perf_env, argc, argv);
322	status = p->fn(argc, argv);
323	perf_config__exit();
324	exit_browser(status);
325	perf_env__exit(&perf_env);
326
327	if (status)
328		return status & 0xff;
329
330	/* Somebody closed stdout? */
331	if (fstat(fileno(stdout), &st))
332		return 0;
333	/* Ignore write errors for pipes and sockets.. */
334	if (S_ISFIFO(st.st_mode) || S_ISSOCK(st.st_mode))
335		return 0;
336
337	status = 1;
338	/* Check for ENOSPC and EIO errors.. */
339	if (fflush(stdout)) {
340		fprintf(stderr, "write failure on standard output: %s",
341			str_error_r(errno, sbuf, sizeof(sbuf)));
342		goto out;
343	}
344	if (ferror(stdout)) {
345		fprintf(stderr, "unknown write failure on standard output");
346		goto out;
347	}
348	if (fclose(stdout)) {
349		fprintf(stderr, "close failed on standard output: %s",
350			str_error_r(errno, sbuf, sizeof(sbuf)));
351		goto out;
352	}
353	status = 0;
354out:
355	return status;
356}
357
358static void handle_internal_command(int argc, const char **argv)
359{
360	const char *cmd = argv[0];
361	unsigned int i;
362
363	/* Turn "perf cmd --help" into "perf help cmd" */
364	if (argc > 1 && !strcmp(argv[1], "--help")) {
365		argv[1] = argv[0];
366		argv[0] = cmd = "help";
367	}
368
369	for (i = 0; i < ARRAY_SIZE(commands); i++) {
370		struct cmd_struct *p = commands+i;
371		if (p->fn == NULL)
372			continue;
373		if (strcmp(p->cmd, cmd))
374			continue;
375		exit(run_builtin(p, argc, argv));
376	}
377}
378
379static void execv_dashed_external(const char **argv)
380{
381	char *cmd;
382	const char *tmp;
383	int status;
384
385	if (asprintf(&cmd, "perf-%s", argv[0]) < 0)
386		goto do_die;
387
388	/*
389	 * argv[0] must be the perf command, but the argv array
390	 * belongs to the caller, and may be reused in
391	 * subsequent loop iterations. Save argv[0] and
392	 * restore it on error.
393	 */
394	tmp = argv[0];
395	argv[0] = cmd;
396
397	/*
398	 * if we fail because the command is not found, it is
399	 * OK to return. Otherwise, we just pass along the status code.
400	 */
401	status = run_command_v_opt(argv, 0);
402	if (status != -ERR_RUN_COMMAND_EXEC) {
403		if (IS_RUN_COMMAND_ERR(status)) {
404do_die:
405			pr_err("FATAL: unable to run '%s'", argv[0]);
406			status = -128;
407		}
408		exit(-status);
409	}
410	errno = ENOENT; /* as if we called execvp */
411
412	argv[0] = tmp;
413	zfree(&cmd);
414}
415
416static int run_argv(int *argcp, const char ***argv)
417{
418	/* See if it's an internal command */
419	handle_internal_command(*argcp, *argv);
420
421	/* .. then try the external ones */
422	execv_dashed_external(*argv);
423	return 0;
424}
425
426static int libperf_print(enum libperf_print_level level,
427			 const char *fmt, va_list ap)
428{
429	return veprintf(level, verbose, fmt, ap);
430}
431
432int main(int argc, const char **argv)
433{
434	int err;
435	const char *cmd;
436	char sbuf[STRERR_BUFSIZE];
437
438	perf_debug_setup();
439
440	/* libsubcmd init */
441	exec_cmd_init("perf", PREFIX, PERF_EXEC_PATH, EXEC_PATH_ENVIRONMENT);
442	pager_init(PERF_PAGER_ENVIRONMENT);
443
444	libperf_init(libperf_print);
445
446	cmd = extract_argv0_path(argv[0]);
447	if (!cmd)
448		cmd = "perf-help";
449
450	srandom(time(NULL));
451
452	/* Setting $PERF_CONFIG makes perf read _only_ the given config file. */
453	config_exclusive_filename = getenv("PERF_CONFIG");
454
455	err = perf_config(perf_default_config, NULL);
456	if (err)
457		return err;
458	set_buildid_dir(NULL);
459
460	/*
461	 * "perf-xxxx" is the same as "perf xxxx", but we obviously:
462	 *
463	 *  - cannot take flags in between the "perf" and the "xxxx".
464	 *  - cannot execute it externally (since it would just do
465	 *    the same thing over again)
466	 *
467	 * So we just directly call the internal command handler. If that one
468	 * fails to handle this, then maybe we just run a renamed perf binary
469	 * that contains a dash in its name. To handle this scenario, we just
470	 * fall through and ignore the "xxxx" part of the command string.
471	 */
472	if (strstarts(cmd, "perf-")) {
473		cmd += 5;
474		argv[0] = cmd;
475		handle_internal_command(argc, argv);
476		/*
477		 * If the command is handled, the above function does not
478		 * return undo changes and fall through in such a case.
479		 */
480		cmd -= 5;
481		argv[0] = cmd;
482	}
483	if (strstarts(cmd, "trace")) {
484#ifndef HAVE_LIBTRACEEVENT
485		fprintf(stderr,
486			"trace command not available: missing libtraceevent devel package at build time.\n");
487		goto out;
488#elif !defined(HAVE_LIBAUDIT_SUPPORT) && !defined(HAVE_SYSCALL_TABLE_SUPPORT)
489		fprintf(stderr,
490			"trace command not available: missing audit-libs devel package at build time.\n");
491		goto out;
492#else
493		setup_path();
494		argv[0] = "trace";
495		return cmd_trace(argc, argv);
496#endif
497	}
498	/* Look for flags.. */
499	argv++;
500	argc--;
501	handle_options(&argv, &argc, NULL);
502	commit_pager_choice();
503
504	if (argc > 0) {
505		if (strstarts(argv[0], "--"))
506			argv[0] += 2;
507	} else {
508		/* The user didn't specify a command; give them help */
509		printf("\n usage: %s\n\n", perf_usage_string);
510		list_common_cmds_help();
511		printf("\n %s\n\n", perf_more_info_string);
512		goto out;
513	}
514	cmd = argv[0];
515
516	test_attr__init();
517
518	/*
519	 * We use PATH to find perf commands, but we prepend some higher
520	 * precedence paths: the "--exec-path" option, the PERF_EXEC_PATH
521	 * environment, and the $(perfexecdir) from the Makefile at build
522	 * time.
523	 */
524	setup_path();
525	/*
526	 * Block SIGWINCH notifications so that the thread that wants it can
527	 * unblock and get syscalls like select interrupted instead of waiting
528	 * forever while the signal goes to some other non interested thread.
529	 */
530	pthread__block_sigwinch();
531
532	while (1) {
533		static int done_help;
534
535		run_argv(&argc, &argv);
536
537		if (errno != ENOENT)
538			break;
539
540		if (!done_help) {
541			cmd = argv[0] = help_unknown_cmd(cmd);
542			done_help = 1;
543		} else
544			break;
545	}
546
547	fprintf(stderr, "Failed to run command '%s': %s\n",
548		cmd, str_error_r(errno, sbuf, sizeof(sbuf)));
549out:
550	return 1;
551}
552