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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}
v5.9
 
  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
 42const char perf_usage_string[] =
 43	"perf [--version] [--help] [OPTIONS] COMMAND [ARGS]";
 44
 45const char perf_more_info_string[] =
 46	"See 'perf help COMMAND' for more information on a specific command.";
 47
 48static int use_pager = -1;
 49const char *input_name;
 50
 51struct cmd_struct {
 52	const char *cmd;
 53	int (*fn)(int, const char **);
 54	int option;
 55};
 56
 57static 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
 93struct pager_config {
 94	const char *cmd;
 95	int val;
 96};
 97
 98static 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" */
107static 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
117static 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 */
131static 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
141static 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
155struct 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
170static 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
295static 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;
345out:
346	return status;
347}
348
349static 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
368static 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)) {
393do_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
405static 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
415static 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
424void 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
433static 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
439int 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)));
552out:
553	return 1;
554}