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v4.17
  1// SPDX-License-Identifier: GPL-2.0
  2/*
  3 * perf.c
  4 *
  5 * Performance analysis utility.
  6 *
  7 * This is the main hub from which the sub-commands (perf stat,
  8 * perf top, perf record, perf report, etc.) are started.
  9 */
 10#include "builtin.h"
 11
 12#include "util/env.h"
 13#include <subcmd/exec-cmd.h>
 14#include "util/config.h"
 15#include "util/quote.h"
 16#include <subcmd/run-command.h>
 17#include "util/parse-events.h"
 18#include <subcmd/parse-options.h>
 19#include "util/bpf-loader.h"
 20#include "util/debug.h"
 21#include "util/event.h"
 22#include <api/fs/fs.h>
 23#include <api/fs/tracing_path.h>
 24#include <errno.h>
 25#include <pthread.h>
 26#include <signal.h>
 27#include <stdlib.h>
 28#include <time.h>
 29#include <sys/types.h>
 30#include <sys/stat.h>
 31#include <unistd.h>
 32#include <linux/kernel.h>
 33
 34const char perf_usage_string[] =
 35	"perf [--version] [--help] [OPTIONS] COMMAND [ARGS]";
 36
 37const char perf_more_info_string[] =
 38	"See 'perf help COMMAND' for more information on a specific command.";
 39
 
 40static int use_pager = -1;
 41const char *input_name;
 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	{ "buildid-cache", cmd_buildid_cache, 0 },
 51	{ "buildid-list", cmd_buildid_list, 0 },
 52	{ "config",	cmd_config,	0 },
 53	{ "c2c",	cmd_c2c,	0 },
 54	{ "diff",	cmd_diff,	0 },
 55	{ "evlist",	cmd_evlist,	0 },
 56	{ "help",	cmd_help,	0 },
 57	{ "kallsyms",	cmd_kallsyms,	0 },
 58	{ "list",	cmd_list,	0 },
 59	{ "record",	cmd_record,	0 },
 60	{ "report",	cmd_report,	0 },
 61	{ "bench",	cmd_bench,	0 },
 62	{ "stat",	cmd_stat,	0 },
 63	{ "timechart",	cmd_timechart,	0 },
 64	{ "top",	cmd_top,	0 },
 65	{ "annotate",	cmd_annotate,	0 },
 66	{ "version",	cmd_version,	0 },
 67	{ "script",	cmd_script,	0 },
 68	{ "sched",	cmd_sched,	0 },
 69#ifdef HAVE_LIBELF_SUPPORT
 70	{ "probe",	cmd_probe,	0 },
 71#endif
 72	{ "kmem",	cmd_kmem,	0 },
 73	{ "lock",	cmd_lock,	0 },
 74	{ "kvm",	cmd_kvm,	0 },
 75	{ "test",	cmd_test,	0 },
 76#if defined(HAVE_LIBAUDIT_SUPPORT) || defined(HAVE_SYSCALL_TABLE_SUPPORT)
 77	{ "trace",	cmd_trace,	0 },
 78#endif
 79	{ "inject",	cmd_inject,	0 },
 80	{ "mem",	cmd_mem,	0 },
 81	{ "data",	cmd_data,	0 },
 82	{ "ftrace",	cmd_ftrace,	0 },
 83};
 84
 85struct pager_config {
 86	const char *cmd;
 87	int val;
 88};
 89
 90static int pager_command_config(const char *var, const char *value, void *data)
 91{
 92	struct pager_config *c = data;
 93	if (strstarts(var, "pager.") && !strcmp(var + 6, c->cmd))
 94		c->val = perf_config_bool(var, value);
 95	return 0;
 96}
 97
 98/* returns 0 for "no pager", 1 for "use pager", and -1 for "not specified" */
 99static int check_pager_config(const char *cmd)
100{
101	int err;
102	struct pager_config c;
103	c.cmd = cmd;
104	c.val = -1;
105	err = perf_config(pager_command_config, &c);
106	return err ?: c.val;
107}
108
109static int browser_command_config(const char *var, const char *value, void *data)
110{
111	struct pager_config *c = data;
112	if (strstarts(var, "tui.") && !strcmp(var + 4, c->cmd))
113		c->val = perf_config_bool(var, value);
114	if (strstarts(var, "gtk.") && !strcmp(var + 4, c->cmd))
115		c->val = perf_config_bool(var, value) ? 2 : 0;
116	return 0;
117}
118
119/*
120 * returns 0 for "no tui", 1 for "use tui", 2 for "use gtk",
121 * and -1 for "not specified"
122 */
123static int check_browser_config(const char *cmd)
124{
125	int err;
126	struct pager_config c;
127	c.cmd = cmd;
128	c.val = -1;
129	err = perf_config(browser_command_config, &c);
130	return err ?: c.val;
131}
132
133static void commit_pager_choice(void)
134{
135	switch (use_pager) {
136	case 0:
137		setenv(PERF_PAGER_ENVIRONMENT, "cat", 1);
138		break;
139	case 1:
140		/* setup_pager(); */
141		break;
142	default:
143		break;
144	}
145}
146
147struct option options[] = {
148	OPT_ARGUMENT("help", "help"),
149	OPT_ARGUMENT("version", "version"),
150	OPT_ARGUMENT("exec-path", "exec-path"),
151	OPT_ARGUMENT("html-path", "html-path"),
152	OPT_ARGUMENT("paginate", "paginate"),
153	OPT_ARGUMENT("no-pager", "no-pager"),
154	OPT_ARGUMENT("debugfs-dir", "debugfs-dir"),
155	OPT_ARGUMENT("buildid-dir", "buildid-dir"),
156	OPT_ARGUMENT("list-cmds", "list-cmds"),
157	OPT_ARGUMENT("list-opts", "list-opts"),
158	OPT_ARGUMENT("debug", "debug"),
159	OPT_END()
160};
161
162static int handle_options(const char ***argv, int *argc, int *envchanged)
163{
164	int handled = 0;
165
166	while (*argc > 0) {
167		const char *cmd = (*argv)[0];
168		if (cmd[0] != '-')
169			break;
170
171		/*
172		 * For legacy reasons, the "version" and "help"
173		 * commands can be written with "--" prepended
174		 * to make them look like flags.
175		 */
176		if (!strcmp(cmd, "--help") || !strcmp(cmd, "--version"))
177			break;
178
179		/*
180		 * Shortcut for '-h' and '-v' options to invoke help
181		 * and version command.
182		 */
183		if (!strcmp(cmd, "-h")) {
184			(*argv)[0] = "--help";
185			break;
186		}
187
188		if (!strcmp(cmd, "-v")) {
189			(*argv)[0] = "--version";
190			break;
191		}
192
193		if (!strcmp(cmd, "-vv")) {
194			(*argv)[0] = "version";
195			version_verbose = 1;
196			break;
197		}
198
199		/*
200		 * Check remaining flags.
201		 */
202		if (strstarts(cmd, CMD_EXEC_PATH)) {
203			cmd += strlen(CMD_EXEC_PATH);
204			if (*cmd == '=')
205				set_argv_exec_path(cmd + 1);
206			else {
207				puts(get_argv_exec_path());
208				exit(0);
209			}
210		} else if (!strcmp(cmd, "--html-path")) {
211			puts(system_path(PERF_HTML_PATH));
212			exit(0);
213		} else if (!strcmp(cmd, "-p") || !strcmp(cmd, "--paginate")) {
214			use_pager = 1;
215		} else if (!strcmp(cmd, "--no-pager")) {
216			use_pager = 0;
217			if (envchanged)
218				*envchanged = 1;
219		} else if (!strcmp(cmd, "--debugfs-dir")) {
220			if (*argc < 2) {
221				fprintf(stderr, "No directory given for --debugfs-dir.\n");
222				usage(perf_usage_string);
223			}
224			tracing_path_set((*argv)[1]);
225			if (envchanged)
226				*envchanged = 1;
227			(*argv)++;
228			(*argc)--;
229		} else if (!strcmp(cmd, "--buildid-dir")) {
230			if (*argc < 2) {
231				fprintf(stderr, "No directory given for --buildid-dir.\n");
232				usage(perf_usage_string);
233			}
234			set_buildid_dir((*argv)[1]);
235			if (envchanged)
236				*envchanged = 1;
237			(*argv)++;
238			(*argc)--;
239		} else if (strstarts(cmd, CMD_DEBUGFS_DIR)) {
240			tracing_path_set(cmd + strlen(CMD_DEBUGFS_DIR));
241			fprintf(stderr, "dir: %s\n", tracing_path);
242			if (envchanged)
243				*envchanged = 1;
244		} else if (!strcmp(cmd, "--list-cmds")) {
245			unsigned int i;
246
247			for (i = 0; i < ARRAY_SIZE(commands); i++) {
248				struct cmd_struct *p = commands+i;
249				printf("%s ", p->cmd);
250			}
251			putchar('\n');
252			exit(0);
253		} else if (!strcmp(cmd, "--list-opts")) {
254			unsigned int i;
255
256			for (i = 0; i < ARRAY_SIZE(options)-1; i++) {
257				struct option *p = options+i;
258				printf("--%s ", p->long_name);
259			}
260			putchar('\n');
261			exit(0);
262		} else if (!strcmp(cmd, "--debug")) {
263			if (*argc < 2) {
264				fprintf(stderr, "No variable specified for --debug.\n");
265				usage(perf_usage_string);
266			}
267			if (perf_debug_option((*argv)[1]))
268				usage(perf_usage_string);
269
270			(*argv)++;
271			(*argc)--;
272		} else {
273			fprintf(stderr, "Unknown option: %s\n", cmd);
274			usage(perf_usage_string);
275		}
276
277		(*argv)++;
278		(*argc)--;
279		handled++;
280	}
281	return handled;
282}
283
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
284#define RUN_SETUP	(1<<0)
285#define USE_PAGER	(1<<1)
286
287static int run_builtin(struct cmd_struct *p, int argc, const char **argv)
288{
289	int status;
290	struct stat st;
 
291	char sbuf[STRERR_BUFSIZE];
292
 
 
 
 
293	if (use_browser == -1)
294		use_browser = check_browser_config(p->cmd);
295
296	if (use_pager == -1 && p->option & RUN_SETUP)
297		use_pager = check_pager_config(p->cmd);
298	if (use_pager == -1 && p->option & USE_PAGER)
299		use_pager = 1;
300	commit_pager_choice();
301
302	perf_env__set_cmdline(&perf_env, argc, argv);
303	status = p->fn(argc, argv);
304	perf_config__exit();
305	exit_browser(status);
306	perf_env__exit(&perf_env);
307	bpf__clear();
308
309	if (status)
310		return status & 0xff;
311
312	/* Somebody closed stdout? */
313	if (fstat(fileno(stdout), &st))
314		return 0;
315	/* Ignore write errors for pipes and sockets.. */
316	if (S_ISFIFO(st.st_mode) || S_ISSOCK(st.st_mode))
317		return 0;
318
319	status = 1;
320	/* Check for ENOSPC and EIO errors.. */
321	if (fflush(stdout)) {
322		fprintf(stderr, "write failure on standard output: %s",
323			str_error_r(errno, sbuf, sizeof(sbuf)));
324		goto out;
325	}
326	if (ferror(stdout)) {
327		fprintf(stderr, "unknown write failure on standard output");
328		goto out;
329	}
330	if (fclose(stdout)) {
331		fprintf(stderr, "close failed on standard output: %s",
332			str_error_r(errno, sbuf, sizeof(sbuf)));
333		goto out;
334	}
335	status = 0;
336out:
337	return status;
338}
339
340static void handle_internal_command(int argc, const char **argv)
341{
342	const char *cmd = argv[0];
343	unsigned int i;
 
 
 
 
 
 
 
 
 
 
344
345	/* Turn "perf cmd --help" into "perf help cmd" */
346	if (argc > 1 && !strcmp(argv[1], "--help")) {
347		argv[1] = argv[0];
348		argv[0] = cmd = "help";
349	}
350
351	for (i = 0; i < ARRAY_SIZE(commands); i++) {
352		struct cmd_struct *p = commands+i;
353		if (strcmp(p->cmd, cmd))
354			continue;
355		exit(run_builtin(p, argc, argv));
356	}
357}
358
359static void execv_dashed_external(const char **argv)
360{
361	char *cmd;
362	const char *tmp;
363	int status;
364
365	if (asprintf(&cmd, "perf-%s", argv[0]) < 0)
366		goto do_die;
367
368	/*
369	 * argv[0] must be the perf command, but the argv array
370	 * belongs to the caller, and may be reused in
371	 * subsequent loop iterations. Save argv[0] and
372	 * restore it on error.
373	 */
374	tmp = argv[0];
375	argv[0] = cmd;
376
377	/*
378	 * if we fail because the command is not found, it is
379	 * OK to return. Otherwise, we just pass along the status code.
380	 */
381	status = run_command_v_opt(argv, 0);
382	if (status != -ERR_RUN_COMMAND_EXEC) {
383		if (IS_RUN_COMMAND_ERR(status)) {
384do_die:
385			pr_err("FATAL: unable to run '%s'", argv[0]);
386			status = -128;
387		}
388		exit(-status);
389	}
390	errno = ENOENT; /* as if we called execvp */
391
392	argv[0] = tmp;
393	zfree(&cmd);
394}
395
396static int run_argv(int *argcp, const char ***argv)
397{
398	/* See if it's an internal command */
399	handle_internal_command(*argcp, *argv);
400
401	/* .. then try the external ones */
402	execv_dashed_external(*argv);
403	return 0;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
404}
405
406static void pthread__block_sigwinch(void)
407{
408	sigset_t set;
409
410	sigemptyset(&set);
411	sigaddset(&set, SIGWINCH);
412	pthread_sigmask(SIG_BLOCK, &set, NULL);
413}
414
415void pthread__unblock_sigwinch(void)
416{
417	sigset_t set;
418
419	sigemptyset(&set);
420	sigaddset(&set, SIGWINCH);
421	pthread_sigmask(SIG_UNBLOCK, &set, NULL);
422}
423
424#ifdef _SC_LEVEL1_DCACHE_LINESIZE
425#define cache_line_size(cacheline_sizep) *cacheline_sizep = sysconf(_SC_LEVEL1_DCACHE_LINESIZE)
426#else
427static void cache_line_size(int *cacheline_sizep)
428{
429	if (sysfs__read_int("devices/system/cpu/cpu0/cache/index0/coherency_line_size", cacheline_sizep))
430		pr_debug("cannot determine cache line size");
431}
432#endif
433
434int main(int argc, const char **argv)
435{
436	int err;
437	const char *cmd;
438	char sbuf[STRERR_BUFSIZE];
439	int value;
440
441	/* libsubcmd init */
442	exec_cmd_init("perf", PREFIX, PERF_EXEC_PATH, EXEC_PATH_ENVIRONMENT);
443	pager_init(PERF_PAGER_ENVIRONMENT);
444
445	/* The page_size is placed in util object. */
446	page_size = sysconf(_SC_PAGE_SIZE);
447	cache_line_size(&cacheline_size);
448
449	if (sysctl__read_int("kernel/perf_event_max_stack", &value) == 0)
450		sysctl_perf_event_max_stack = value;
451
452	if (sysctl__read_int("kernel/perf_event_max_contexts_per_stack", &value) == 0)
453		sysctl_perf_event_max_contexts_per_stack = value;
454
455	cmd = extract_argv0_path(argv[0]);
456	if (!cmd)
457		cmd = "perf-help";
458
459	srandom(time(NULL));
460
461	perf_config__init();
462	err = perf_config(perf_default_config, NULL);
463	if (err)
464		return err;
465	set_buildid_dir(NULL);
466
467	/* get debugfs/tracefs mount point from /proc/mounts */
468	tracing_path_mount();
469
470	/*
471	 * "perf-xxxx" is the same as "perf xxxx", but we obviously:
472	 *
473	 *  - cannot take flags in between the "perf" and the "xxxx".
474	 *  - cannot execute it externally (since it would just do
475	 *    the same thing over again)
476	 *
477	 * So we just directly call the internal command handler. If that one
478	 * fails to handle this, then maybe we just run a renamed perf binary
479	 * that contains a dash in its name. To handle this scenario, we just
480	 * fall through and ignore the "xxxx" part of the command string.
481	 */
482	if (strstarts(cmd, "perf-")) {
483		cmd += 5;
484		argv[0] = cmd;
485		handle_internal_command(argc, argv);
486		/*
487		 * If the command is handled, the above function does not
488		 * return undo changes and fall through in such a case.
489		 */
490		cmd -= 5;
491		argv[0] = cmd;
492	}
493	if (strstarts(cmd, "trace")) {
494#if defined(HAVE_LIBAUDIT_SUPPORT) || defined(HAVE_SYSCALL_TABLE_SUPPORT)
495		setup_path();
496		argv[0] = "trace";
497		return cmd_trace(argc, argv);
498#else
499		fprintf(stderr,
500			"trace command not available: missing audit-libs devel package at build time.\n");
501		goto out;
502#endif
503	}
504	/* Look for flags.. */
505	argv++;
506	argc--;
507	handle_options(&argv, &argc, NULL);
508	commit_pager_choice();
509
510	if (argc > 0) {
511		if (strstarts(argv[0], "--"))
512			argv[0] += 2;
513	} else {
514		/* The user didn't specify a command; give them help */
515		printf("\n usage: %s\n\n", perf_usage_string);
516		list_common_cmds_help();
517		printf("\n %s\n\n", perf_more_info_string);
518		goto out;
519	}
520	cmd = argv[0];
521
522	test_attr__init();
523
524	/*
525	 * We use PATH to find perf commands, but we prepend some higher
526	 * precedence paths: the "--exec-path" option, the PERF_EXEC_PATH
527	 * environment, and the $(perfexecdir) from the Makefile at build
528	 * time.
529	 */
530	setup_path();
531	/*
532	 * Block SIGWINCH notifications so that the thread that wants it can
533	 * unblock and get syscalls like select interrupted instead of waiting
534	 * forever while the signal goes to some other non interested thread.
535	 */
536	pthread__block_sigwinch();
537
538	perf_debug_setup();
539
540	while (1) {
541		static int done_help;
542
543		run_argv(&argc, &argv);
544
545		if (errno != ENOENT)
546			break;
547
 
 
 
 
 
 
548		if (!done_help) {
549			cmd = argv[0] = help_unknown_cmd(cmd);
550			done_help = 1;
551		} else
552			break;
553	}
554
555	fprintf(stderr, "Failed to run command '%s': %s\n",
556		cmd, str_error_r(errno, sbuf, sizeof(sbuf)));
557out:
558	return 1;
559}
v4.10.11
 
  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 <api/fs/fs.h>
 21#include <api/fs/tracing_path.h>
 
 22#include <pthread.h>
 
 23#include <stdlib.h>
 24#include <time.h>
 
 
 
 
 25
 26const char perf_usage_string[] =
 27	"perf [--version] [--help] [OPTIONS] COMMAND [ARGS]";
 28
 29const char perf_more_info_string[] =
 30	"See 'perf help COMMAND' for more information on a specific command.";
 31
 32int use_browser = -1;
 33static int use_pager = -1;
 34const char *input_name;
 35
 36struct cmd_struct {
 37	const char *cmd;
 38	int (*fn)(int, const char **, const char *);
 39	int option;
 40};
 41
 42static struct cmd_struct commands[] = {
 43	{ "buildid-cache", cmd_buildid_cache, 0 },
 44	{ "buildid-list", cmd_buildid_list, 0 },
 45	{ "config",	cmd_config,	0 },
 46	{ "c2c",	cmd_c2c,	0 },
 47	{ "diff",	cmd_diff,	0 },
 48	{ "evlist",	cmd_evlist,	0 },
 49	{ "help",	cmd_help,	0 },
 
 50	{ "list",	cmd_list,	0 },
 51	{ "record",	cmd_record,	0 },
 52	{ "report",	cmd_report,	0 },
 53	{ "bench",	cmd_bench,	0 },
 54	{ "stat",	cmd_stat,	0 },
 55	{ "timechart",	cmd_timechart,	0 },
 56	{ "top",	cmd_top,	0 },
 57	{ "annotate",	cmd_annotate,	0 },
 58	{ "version",	cmd_version,	0 },
 59	{ "script",	cmd_script,	0 },
 60	{ "sched",	cmd_sched,	0 },
 61#ifdef HAVE_LIBELF_SUPPORT
 62	{ "probe",	cmd_probe,	0 },
 63#endif
 64	{ "kmem",	cmd_kmem,	0 },
 65	{ "lock",	cmd_lock,	0 },
 66	{ "kvm",	cmd_kvm,	0 },
 67	{ "test",	cmd_test,	0 },
 68#ifdef HAVE_LIBAUDIT_SUPPORT
 69	{ "trace",	cmd_trace,	0 },
 70#endif
 71	{ "inject",	cmd_inject,	0 },
 72	{ "mem",	cmd_mem,	0 },
 73	{ "data",	cmd_data,	0 },
 
 74};
 75
 76struct pager_config {
 77	const char *cmd;
 78	int val;
 79};
 80
 81static int pager_command_config(const char *var, const char *value, void *data)
 82{
 83	struct pager_config *c = data;
 84	if (!prefixcmp(var, "pager.") && !strcmp(var + 6, c->cmd))
 85		c->val = perf_config_bool(var, value);
 86	return 0;
 87}
 88
 89/* returns 0 for "no pager", 1 for "use pager", and -1 for "not specified" */
 90int check_pager_config(const char *cmd)
 91{
 
 92	struct pager_config c;
 93	c.cmd = cmd;
 94	c.val = -1;
 95	perf_config(pager_command_config, &c);
 96	return c.val;
 97}
 98
 99static int browser_command_config(const char *var, const char *value, void *data)
100{
101	struct pager_config *c = data;
102	if (!prefixcmp(var, "tui.") && !strcmp(var + 4, c->cmd))
103		c->val = perf_config_bool(var, value);
104	if (!prefixcmp(var, "gtk.") && !strcmp(var + 4, c->cmd))
105		c->val = perf_config_bool(var, value) ? 2 : 0;
106	return 0;
107}
108
109/*
110 * returns 0 for "no tui", 1 for "use tui", 2 for "use gtk",
111 * and -1 for "not specified"
112 */
113static int check_browser_config(const char *cmd)
114{
 
115	struct pager_config c;
116	c.cmd = cmd;
117	c.val = -1;
118	perf_config(browser_command_config, &c);
119	return c.val;
120}
121
122static void commit_pager_choice(void)
123{
124	switch (use_pager) {
125	case 0:
126		setenv(PERF_PAGER_ENVIRONMENT, "cat", 1);
127		break;
128	case 1:
129		/* setup_pager(); */
130		break;
131	default:
132		break;
133	}
134}
135
136struct option options[] = {
137	OPT_ARGUMENT("help", "help"),
138	OPT_ARGUMENT("version", "version"),
139	OPT_ARGUMENT("exec-path", "exec-path"),
140	OPT_ARGUMENT("html-path", "html-path"),
141	OPT_ARGUMENT("paginate", "paginate"),
142	OPT_ARGUMENT("no-pager", "no-pager"),
143	OPT_ARGUMENT("debugfs-dir", "debugfs-dir"),
144	OPT_ARGUMENT("buildid-dir", "buildid-dir"),
145	OPT_ARGUMENT("list-cmds", "list-cmds"),
146	OPT_ARGUMENT("list-opts", "list-opts"),
147	OPT_ARGUMENT("debug", "debug"),
148	OPT_END()
149};
150
151static int handle_options(const char ***argv, int *argc, int *envchanged)
152{
153	int handled = 0;
154
155	while (*argc > 0) {
156		const char *cmd = (*argv)[0];
157		if (cmd[0] != '-')
158			break;
159
160		/*
161		 * For legacy reasons, the "version" and "help"
162		 * commands can be written with "--" prepended
163		 * to make them look like flags.
164		 */
165		if (!strcmp(cmd, "--help") || !strcmp(cmd, "--version"))
166			break;
167
168		/*
169		 * Shortcut for '-h' and '-v' options to invoke help
170		 * and version command.
171		 */
172		if (!strcmp(cmd, "-h")) {
173			(*argv)[0] = "--help";
174			break;
175		}
176
177		if (!strcmp(cmd, "-v")) {
178			(*argv)[0] = "--version";
179			break;
180		}
181
 
 
 
 
 
 
182		/*
183		 * Check remaining flags.
184		 */
185		if (!prefixcmp(cmd, CMD_EXEC_PATH)) {
186			cmd += strlen(CMD_EXEC_PATH);
187			if (*cmd == '=')
188				set_argv_exec_path(cmd + 1);
189			else {
190				puts(get_argv_exec_path());
191				exit(0);
192			}
193		} else if (!strcmp(cmd, "--html-path")) {
194			puts(system_path(PERF_HTML_PATH));
195			exit(0);
196		} else if (!strcmp(cmd, "-p") || !strcmp(cmd, "--paginate")) {
197			use_pager = 1;
198		} else if (!strcmp(cmd, "--no-pager")) {
199			use_pager = 0;
200			if (envchanged)
201				*envchanged = 1;
202		} else if (!strcmp(cmd, "--debugfs-dir")) {
203			if (*argc < 2) {
204				fprintf(stderr, "No directory given for --debugfs-dir.\n");
205				usage(perf_usage_string);
206			}
207			tracing_path_set((*argv)[1]);
208			if (envchanged)
209				*envchanged = 1;
210			(*argv)++;
211			(*argc)--;
212		} else if (!strcmp(cmd, "--buildid-dir")) {
213			if (*argc < 2) {
214				fprintf(stderr, "No directory given for --buildid-dir.\n");
215				usage(perf_usage_string);
216			}
217			set_buildid_dir((*argv)[1]);
218			if (envchanged)
219				*envchanged = 1;
220			(*argv)++;
221			(*argc)--;
222		} else if (!prefixcmp(cmd, CMD_DEBUGFS_DIR)) {
223			tracing_path_set(cmd + strlen(CMD_DEBUGFS_DIR));
224			fprintf(stderr, "dir: %s\n", tracing_path);
225			if (envchanged)
226				*envchanged = 1;
227		} else if (!strcmp(cmd, "--list-cmds")) {
228			unsigned int i;
229
230			for (i = 0; i < ARRAY_SIZE(commands); i++) {
231				struct cmd_struct *p = commands+i;
232				printf("%s ", p->cmd);
233			}
234			putchar('\n');
235			exit(0);
236		} else if (!strcmp(cmd, "--list-opts")) {
237			unsigned int i;
238
239			for (i = 0; i < ARRAY_SIZE(options)-1; i++) {
240				struct option *p = options+i;
241				printf("--%s ", p->long_name);
242			}
243			putchar('\n');
244			exit(0);
245		} else if (!strcmp(cmd, "--debug")) {
246			if (*argc < 2) {
247				fprintf(stderr, "No variable specified for --debug.\n");
248				usage(perf_usage_string);
249			}
250			if (perf_debug_option((*argv)[1]))
251				usage(perf_usage_string);
252
253			(*argv)++;
254			(*argc)--;
255		} else {
256			fprintf(stderr, "Unknown option: %s\n", cmd);
257			usage(perf_usage_string);
258		}
259
260		(*argv)++;
261		(*argc)--;
262		handled++;
263	}
264	return handled;
265}
266
267static int handle_alias(int *argcp, const char ***argv)
268{
269	int envchanged = 0, ret = 0, saved_errno = errno;
270	int count, option_count;
271	const char **new_argv;
272	const char *alias_command;
273	char *alias_string;
274
275	alias_command = (*argv)[0];
276	alias_string = alias_lookup(alias_command);
277	if (alias_string) {
278		if (alias_string[0] == '!') {
279			if (*argcp > 1) {
280				struct strbuf buf;
281
282				if (strbuf_init(&buf, PATH_MAX) < 0 ||
283				    strbuf_addstr(&buf, alias_string) < 0 ||
284				    sq_quote_argv(&buf, (*argv) + 1,
285						  PATH_MAX) < 0)
286					die("Failed to allocate memory.");
287				free(alias_string);
288				alias_string = buf.buf;
289			}
290			ret = system(alias_string + 1);
291			if (ret >= 0 && WIFEXITED(ret) &&
292			    WEXITSTATUS(ret) != 127)
293				exit(WEXITSTATUS(ret));
294			die("Failed to run '%s' when expanding alias '%s'",
295			    alias_string + 1, alias_command);
296		}
297		count = split_cmdline(alias_string, &new_argv);
298		if (count < 0)
299			die("Bad alias.%s string", alias_command);
300		option_count = handle_options(&new_argv, &count, &envchanged);
301		if (envchanged)
302			die("alias '%s' changes environment variables\n"
303				 "You can use '!perf' in the alias to do this.",
304				 alias_command);
305		memmove(new_argv - option_count, new_argv,
306				count * sizeof(char *));
307		new_argv -= option_count;
308
309		if (count < 1)
310			die("empty alias for %s", alias_command);
311
312		if (!strcmp(alias_command, new_argv[0]))
313			die("recursive alias: %s", alias_command);
314
315		new_argv = realloc(new_argv, sizeof(char *) *
316				    (count + *argcp + 1));
317		/* insert after command name */
318		memcpy(new_argv + count, *argv + 1, sizeof(char *) * *argcp);
319		new_argv[count + *argcp] = NULL;
320
321		*argv = new_argv;
322		*argcp += count - 1;
323
324		ret = 1;
325	}
326
327	errno = saved_errno;
328
329	return ret;
330}
331
332const char perf_version_string[] = PERF_VERSION;
333
334#define RUN_SETUP	(1<<0)
335#define USE_PAGER	(1<<1)
336
337static int run_builtin(struct cmd_struct *p, int argc, const char **argv)
338{
339	int status;
340	struct stat st;
341	const char *prefix;
342	char sbuf[STRERR_BUFSIZE];
343
344	prefix = NULL;
345	if (p->option & RUN_SETUP)
346		prefix = NULL; /* setup_perf_directory(); */
347
348	if (use_browser == -1)
349		use_browser = check_browser_config(p->cmd);
350
351	if (use_pager == -1 && p->option & RUN_SETUP)
352		use_pager = check_pager_config(p->cmd);
353	if (use_pager == -1 && p->option & USE_PAGER)
354		use_pager = 1;
355	commit_pager_choice();
356
357	perf_env__set_cmdline(&perf_env, argc, argv);
358	status = p->fn(argc, argv, prefix);
359	perf_config__exit();
360	exit_browser(status);
361	perf_env__exit(&perf_env);
362	bpf__clear();
363
364	if (status)
365		return status & 0xff;
366
367	/* Somebody closed stdout? */
368	if (fstat(fileno(stdout), &st))
369		return 0;
370	/* Ignore write errors for pipes and sockets.. */
371	if (S_ISFIFO(st.st_mode) || S_ISSOCK(st.st_mode))
372		return 0;
373
374	status = 1;
375	/* Check for ENOSPC and EIO errors.. */
376	if (fflush(stdout)) {
377		fprintf(stderr, "write failure on standard output: %s",
378			str_error_r(errno, sbuf, sizeof(sbuf)));
379		goto out;
380	}
381	if (ferror(stdout)) {
382		fprintf(stderr, "unknown write failure on standard output");
383		goto out;
384	}
385	if (fclose(stdout)) {
386		fprintf(stderr, "close failed on standard output: %s",
387			str_error_r(errno, sbuf, sizeof(sbuf)));
388		goto out;
389	}
390	status = 0;
391out:
392	return status;
393}
394
395static void handle_internal_command(int argc, const char **argv)
396{
397	const char *cmd = argv[0];
398	unsigned int i;
399	static const char ext[] = STRIP_EXTENSION;
400
401	if (sizeof(ext) > 1) {
402		i = strlen(argv[0]) - strlen(ext);
403		if (i > 0 && !strcmp(argv[0] + i, ext)) {
404			char *argv0 = strdup(argv[0]);
405			argv[0] = cmd = argv0;
406			argv0[i] = '\0';
407		}
408	}
409
410	/* Turn "perf cmd --help" into "perf help cmd" */
411	if (argc > 1 && !strcmp(argv[1], "--help")) {
412		argv[1] = argv[0];
413		argv[0] = cmd = "help";
414	}
415
416	for (i = 0; i < ARRAY_SIZE(commands); i++) {
417		struct cmd_struct *p = commands+i;
418		if (strcmp(p->cmd, cmd))
419			continue;
420		exit(run_builtin(p, argc, argv));
421	}
422}
423
424static void execv_dashed_external(const char **argv)
425{
426	char *cmd;
427	const char *tmp;
428	int status;
429
430	if (asprintf(&cmd, "perf-%s", argv[0]) < 0)
431		goto do_die;
432
433	/*
434	 * argv[0] must be the perf command, but the argv array
435	 * belongs to the caller, and may be reused in
436	 * subsequent loop iterations. Save argv[0] and
437	 * restore it on error.
438	 */
439	tmp = argv[0];
440	argv[0] = cmd;
441
442	/*
443	 * if we fail because the command is not found, it is
444	 * OK to return. Otherwise, we just pass along the status code.
445	 */
446	status = run_command_v_opt(argv, 0);
447	if (status != -ERR_RUN_COMMAND_EXEC) {
448		if (IS_RUN_COMMAND_ERR(status)) {
449do_die:
450			die("unable to run '%s'", argv[0]);
 
451		}
452		exit(-status);
453	}
454	errno = ENOENT; /* as if we called execvp */
455
456	argv[0] = tmp;
457	zfree(&cmd);
458}
459
460static int run_argv(int *argcp, const char ***argv)
461{
462	int done_alias = 0;
 
463
464	while (1) {
465		/* See if it's an internal command */
466		handle_internal_command(*argcp, *argv);
467
468		/* .. then try the external ones */
469		execv_dashed_external(*argv);
470
471		/* It could be an alias -- this works around the insanity
472		 * of overriding "perf log" with "perf show" by having
473		 * alias.log = show
474		 */
475		if (done_alias || !handle_alias(argcp, argv))
476			break;
477		done_alias = 1;
478	}
479
480	return done_alias;
481}
482
483static void pthread__block_sigwinch(void)
484{
485	sigset_t set;
486
487	sigemptyset(&set);
488	sigaddset(&set, SIGWINCH);
489	pthread_sigmask(SIG_BLOCK, &set, NULL);
490}
491
492void pthread__unblock_sigwinch(void)
493{
494	sigset_t set;
495
496	sigemptyset(&set);
497	sigaddset(&set, SIGWINCH);
498	pthread_sigmask(SIG_UNBLOCK, &set, NULL);
499}
500
501#ifdef _SC_LEVEL1_DCACHE_LINESIZE
502#define cache_line_size(cacheline_sizep) *cacheline_sizep = sysconf(_SC_LEVEL1_DCACHE_LINESIZE)
503#else
504static void cache_line_size(int *cacheline_sizep)
505{
506	if (sysfs__read_int("devices/system/cpu/cpu0/cache/index0/coherency_line_size", cacheline_sizep))
507		pr_debug("cannot determine cache line size");
508}
509#endif
510
511int main(int argc, const char **argv)
512{
 
513	const char *cmd;
514	char sbuf[STRERR_BUFSIZE];
515	int value;
516
517	/* libsubcmd init */
518	exec_cmd_init("perf", PREFIX, PERF_EXEC_PATH, EXEC_PATH_ENVIRONMENT);
519	pager_init(PERF_PAGER_ENVIRONMENT);
520
521	/* The page_size is placed in util object. */
522	page_size = sysconf(_SC_PAGE_SIZE);
523	cache_line_size(&cacheline_size);
524
525	if (sysctl__read_int("kernel/perf_event_max_stack", &value) == 0)
526		sysctl_perf_event_max_stack = value;
527
528	if (sysctl__read_int("kernel/perf_event_max_contexts_per_stack", &value) == 0)
529		sysctl_perf_event_max_contexts_per_stack = value;
530
531	cmd = extract_argv0_path(argv[0]);
532	if (!cmd)
533		cmd = "perf-help";
534
535	srandom(time(NULL));
536
537	perf_config__init();
538	perf_config(perf_default_config, NULL);
 
 
539	set_buildid_dir(NULL);
540
541	/* get debugfs/tracefs mount point from /proc/mounts */
542	tracing_path_mount();
543
544	/*
545	 * "perf-xxxx" is the same as "perf xxxx", but we obviously:
546	 *
547	 *  - cannot take flags in between the "perf" and the "xxxx".
548	 *  - cannot execute it externally (since it would just do
549	 *    the same thing over again)
550	 *
551	 * So we just directly call the internal command handler, and
552	 * die if that one cannot handle it.
 
 
553	 */
554	if (!prefixcmp(cmd, "perf-")) {
555		cmd += 5;
556		argv[0] = cmd;
557		handle_internal_command(argc, argv);
558		fprintf(stderr, "cannot handle %s internally", cmd);
559		goto out;
 
 
 
 
560	}
561	if (!prefixcmp(cmd, "trace")) {
562#ifdef HAVE_LIBAUDIT_SUPPORT
563		setup_path();
564		argv[0] = "trace";
565		return cmd_trace(argc, argv, NULL);
566#else
567		fprintf(stderr,
568			"trace command not available: missing audit-libs devel package at build time.\n");
569		goto out;
570#endif
571	}
572	/* Look for flags.. */
573	argv++;
574	argc--;
575	handle_options(&argv, &argc, NULL);
576	commit_pager_choice();
577
578	if (argc > 0) {
579		if (!prefixcmp(argv[0], "--"))
580			argv[0] += 2;
581	} else {
582		/* The user didn't specify a command; give them help */
583		printf("\n usage: %s\n\n", perf_usage_string);
584		list_common_cmds_help();
585		printf("\n %s\n\n", perf_more_info_string);
586		goto out;
587	}
588	cmd = argv[0];
589
590	test_attr__init();
591
592	/*
593	 * We use PATH to find perf commands, but we prepend some higher
594	 * precedence paths: the "--exec-path" option, the PERF_EXEC_PATH
595	 * environment, and the $(perfexecdir) from the Makefile at build
596	 * time.
597	 */
598	setup_path();
599	/*
600	 * Block SIGWINCH notifications so that the thread that wants it can
601	 * unblock and get syscalls like select interrupted instead of waiting
602	 * forever while the signal goes to some other non interested thread.
603	 */
604	pthread__block_sigwinch();
605
606	perf_debug_setup();
607
608	while (1) {
609		static int done_help;
610		int was_alias = run_argv(&argc, &argv);
 
611
612		if (errno != ENOENT)
613			break;
614
615		if (was_alias) {
616			fprintf(stderr, "Expansion of alias '%s' failed; "
617				"'%s' is not a perf-command\n",
618				cmd, argv[0]);
619			goto out;
620		}
621		if (!done_help) {
622			cmd = argv[0] = help_unknown_cmd(cmd);
623			done_help = 1;
624		} else
625			break;
626	}
627
628	fprintf(stderr, "Failed to run command '%s': %s\n",
629		cmd, str_error_r(errno, sbuf, sizeof(sbuf)));
630out:
631	return 1;
632}