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