624e62d9d1e083add26fdd98d3a12a10b04a2d1e
[muen/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/exec_cmd.h"
12 #include "util/cache.h"
13 #include "util/quote.h"
14 #include "util/run-command.h"
15 #include "util/parse-events.h"
16 #include "util/string.h"
17
18 const char perf_usage_string[] =
19         "perf [--version] [--help] COMMAND [ARGS]";
20
21 const char perf_more_info_string[] =
22         "See 'perf help COMMAND' for more information on a specific command.";
23
24 static int use_pager = -1;
25 struct pager_config {
26         const char *cmd;
27         int val;
28 };
29
30 static char debugfs_mntpt[MAXPATHLEN];
31
32 static int pager_command_config(const char *var, const char *value, void *data)
33 {
34         struct pager_config *c = data;
35         if (!prefixcmp(var, "pager.") && !strcmp(var + 6, c->cmd))
36                 c->val = perf_config_bool(var, value);
37         return 0;
38 }
39
40 /* returns 0 for "no pager", 1 for "use pager", and -1 for "not specified" */
41 int check_pager_config(const char *cmd)
42 {
43         struct pager_config c;
44         c.cmd = cmd;
45         c.val = -1;
46         perf_config(pager_command_config, &c);
47         return c.val;
48 }
49
50 static void commit_pager_choice(void) {
51         switch (use_pager) {
52         case 0:
53                 setenv("PERF_PAGER", "cat", 1);
54                 break;
55         case 1:
56                 /* setup_pager(); */
57                 break;
58         default:
59                 break;
60         }
61 }
62
63 static void set_debugfs_path(void)
64 {
65         char *path;
66
67         path = getenv(PERF_DEBUGFS_ENVIRONMENT);
68         snprintf(debugfs_path, MAXPATHLEN, "%s/%s", path ?: debugfs_mntpt,
69                  "tracing/events");
70 }
71
72 static int handle_options(const char*** argv, int* argc, int* envchanged)
73 {
74         int handled = 0;
75
76         while (*argc > 0) {
77                 const char *cmd = (*argv)[0];
78                 if (cmd[0] != '-')
79                         break;
80
81                 /*
82                  * For legacy reasons, the "version" and "help"
83                  * commands can be written with "--" prepended
84                  * to make them look like flags.
85                  */
86                 if (!strcmp(cmd, "--help") || !strcmp(cmd, "--version"))
87                         break;
88
89                 /*
90                  * Check remaining flags.
91                  */
92                 if (!prefixcmp(cmd, CMD_EXEC_PATH)) {
93                         cmd += strlen(CMD_EXEC_PATH);
94                         if (*cmd == '=')
95                                 perf_set_argv_exec_path(cmd + 1);
96                         else {
97                                 puts(perf_exec_path());
98                                 exit(0);
99                         }
100                 } else if (!strcmp(cmd, "--html-path")) {
101                         puts(system_path(PERF_HTML_PATH));
102                         exit(0);
103                 } else if (!strcmp(cmd, "-p") || !strcmp(cmd, "--paginate")) {
104                         use_pager = 1;
105                 } else if (!strcmp(cmd, "--no-pager")) {
106                         use_pager = 0;
107                         if (envchanged)
108                                 *envchanged = 1;
109                 } else if (!strcmp(cmd, "--perf-dir")) {
110                         if (*argc < 2) {
111                                 fprintf(stderr, "No directory given for --perf-dir.\n" );
112                                 usage(perf_usage_string);
113                         }
114                         setenv(PERF_DIR_ENVIRONMENT, (*argv)[1], 1);
115                         if (envchanged)
116                                 *envchanged = 1;
117                         (*argv)++;
118                         (*argc)--;
119                         handled++;
120                 } else if (!prefixcmp(cmd, CMD_PERF_DIR)) {
121                         setenv(PERF_DIR_ENVIRONMENT, cmd + strlen(CMD_PERF_DIR), 1);
122                         if (envchanged)
123                                 *envchanged = 1;
124                 } else if (!strcmp(cmd, "--work-tree")) {
125                         if (*argc < 2) {
126                                 fprintf(stderr, "No directory given for --work-tree.\n" );
127                                 usage(perf_usage_string);
128                         }
129                         setenv(PERF_WORK_TREE_ENVIRONMENT, (*argv)[1], 1);
130                         if (envchanged)
131                                 *envchanged = 1;
132                         (*argv)++;
133                         (*argc)--;
134                 } else if (!prefixcmp(cmd, CMD_WORK_TREE)) {
135                         setenv(PERF_WORK_TREE_ENVIRONMENT, cmd + strlen(CMD_WORK_TREE), 1);
136                         if (envchanged)
137                                 *envchanged = 1;
138                 } else if (!strcmp(cmd, "--debugfs-dir")) {
139                         if (*argc < 2) {
140                                 fprintf(stderr, "No directory given for --debugfs-dir.\n");
141                                 usage(perf_usage_string);
142                         }
143                         strncpy(debugfs_mntpt, (*argv)[1], MAXPATHLEN);
144                         debugfs_mntpt[MAXPATHLEN - 1] = '\0';
145                         if (envchanged)
146                                 *envchanged = 1;
147                         (*argv)++;
148                         (*argc)--;
149                 } else if (!prefixcmp(cmd, CMD_DEBUGFS_DIR)) {
150                         strncpy(debugfs_mntpt, cmd + strlen(CMD_DEBUGFS_DIR), MAXPATHLEN);
151                         debugfs_mntpt[MAXPATHLEN - 1] = '\0';
152                         if (envchanged)
153                                 *envchanged = 1;
154                 } else {
155                         fprintf(stderr, "Unknown option: %s\n", cmd);
156                         usage(perf_usage_string);
157                 }
158
159                 (*argv)++;
160                 (*argc)--;
161                 handled++;
162         }
163         return handled;
164 }
165
166 static int handle_alias(int *argcp, const char ***argv)
167 {
168         int envchanged = 0, ret = 0, saved_errno = errno;
169         int count, option_count;
170         const char** new_argv;
171         const char *alias_command;
172         char *alias_string;
173
174         alias_command = (*argv)[0];
175         alias_string = alias_lookup(alias_command);
176         if (alias_string) {
177                 if (alias_string[0] == '!') {
178                         if (*argcp > 1) {
179                                 struct strbuf buf;
180
181                                 strbuf_init(&buf, PATH_MAX);
182                                 strbuf_addstr(&buf, alias_string);
183                                 sq_quote_argv(&buf, (*argv) + 1, PATH_MAX);
184                                 free(alias_string);
185                                 alias_string = buf.buf;
186                         }
187                         ret = system(alias_string + 1);
188                         if (ret >= 0 && WIFEXITED(ret) &&
189                             WEXITSTATUS(ret) != 127)
190                                 exit(WEXITSTATUS(ret));
191                         die("Failed to run '%s' when expanding alias '%s'",
192                             alias_string + 1, alias_command);
193                 }
194                 count = split_cmdline(alias_string, &new_argv);
195                 if (count < 0)
196                         die("Bad alias.%s string", alias_command);
197                 option_count = handle_options(&new_argv, &count, &envchanged);
198                 if (envchanged)
199                         die("alias '%s' changes environment variables\n"
200                                  "You can use '!perf' in the alias to do this.",
201                                  alias_command);
202                 memmove(new_argv - option_count, new_argv,
203                                 count * sizeof(char *));
204                 new_argv -= option_count;
205
206                 if (count < 1)
207                         die("empty alias for %s", alias_command);
208
209                 if (!strcmp(alias_command, new_argv[0]))
210                         die("recursive alias: %s", alias_command);
211
212                 new_argv = realloc(new_argv, sizeof(char*) *
213                                     (count + *argcp + 1));
214                 /* insert after command name */
215                 memcpy(new_argv + count, *argv + 1, sizeof(char*) * *argcp);
216                 new_argv[count+*argcp] = NULL;
217
218                 *argv = new_argv;
219                 *argcp += count - 1;
220
221                 ret = 1;
222         }
223
224         errno = saved_errno;
225
226         return ret;
227 }
228
229 const char perf_version_string[] = PERF_VERSION;
230
231 #define RUN_SETUP       (1<<0)
232 #define USE_PAGER       (1<<1)
233 /*
234  * require working tree to be present -- anything uses this needs
235  * RUN_SETUP for reading from the configuration file.
236  */
237 #define NEED_WORK_TREE  (1<<2)
238
239 struct cmd_struct {
240         const char *cmd;
241         int (*fn)(int, const char **, const char *);
242         int option;
243 };
244
245 static int run_builtin(struct cmd_struct *p, int argc, const char **argv)
246 {
247         int status;
248         struct stat st;
249         const char *prefix;
250
251         prefix = NULL;
252         if (p->option & RUN_SETUP)
253                 prefix = NULL; /* setup_perf_directory(); */
254
255         if (use_pager == -1 && p->option & RUN_SETUP)
256                 use_pager = check_pager_config(p->cmd);
257         if (use_pager == -1 && p->option & USE_PAGER)
258                 use_pager = 1;
259         commit_pager_choice();
260         set_debugfs_path();
261
262         status = p->fn(argc, argv, prefix);
263         if (status)
264                 return status & 0xff;
265
266         /* Somebody closed stdout? */
267         if (fstat(fileno(stdout), &st))
268                 return 0;
269         /* Ignore write errors for pipes and sockets.. */
270         if (S_ISFIFO(st.st_mode) || S_ISSOCK(st.st_mode))
271                 return 0;
272
273         /* Check for ENOSPC and EIO errors.. */
274         if (fflush(stdout))
275                 die("write failure on standard output: %s", strerror(errno));
276         if (ferror(stdout))
277                 die("unknown write failure on standard output");
278         if (fclose(stdout))
279                 die("close failed on standard output: %s", strerror(errno));
280         return 0;
281 }
282
283 static void handle_internal_command(int argc, const char **argv)
284 {
285         const char *cmd = argv[0];
286         static struct cmd_struct commands[] = {
287                 { "help", cmd_help, 0 },
288                 { "list", cmd_list, 0 },
289                 { "record", cmd_record, 0 },
290                 { "report", cmd_report, 0 },
291                 { "stat", cmd_stat, 0 },
292                 { "timechart", cmd_timechart, 0 },
293                 { "top", cmd_top, 0 },
294                 { "annotate", cmd_annotate, 0 },
295                 { "version", cmd_version, 0 },
296                 { "trace", cmd_trace, 0 },
297                 { "sched", cmd_sched, 0 },
298         };
299         unsigned int i;
300         static const char ext[] = STRIP_EXTENSION;
301
302         if (sizeof(ext) > 1) {
303                 i = strlen(argv[0]) - strlen(ext);
304                 if (i > 0 && !strcmp(argv[0] + i, ext)) {
305                         char *argv0 = strdup(argv[0]);
306                         argv[0] = cmd = argv0;
307                         argv0[i] = '\0';
308                 }
309         }
310
311         /* Turn "perf cmd --help" into "perf help cmd" */
312         if (argc > 1 && !strcmp(argv[1], "--help")) {
313                 argv[1] = argv[0];
314                 argv[0] = cmd = "help";
315         }
316
317         for (i = 0; i < ARRAY_SIZE(commands); i++) {
318                 struct cmd_struct *p = commands+i;
319                 if (strcmp(p->cmd, cmd))
320                         continue;
321                 exit(run_builtin(p, argc, argv));
322         }
323 }
324
325 static void execv_dashed_external(const char **argv)
326 {
327         struct strbuf cmd = STRBUF_INIT;
328         const char *tmp;
329         int status;
330
331         strbuf_addf(&cmd, "perf-%s", argv[0]);
332
333         /*
334          * argv[0] must be the perf command, but the argv array
335          * belongs to the caller, and may be reused in
336          * subsequent loop iterations. Save argv[0] and
337          * restore it on error.
338          */
339         tmp = argv[0];
340         argv[0] = cmd.buf;
341
342         /*
343          * if we fail because the command is not found, it is
344          * OK to return. Otherwise, we just pass along the status code.
345          */
346         status = run_command_v_opt(argv, 0);
347         if (status != -ERR_RUN_COMMAND_EXEC) {
348                 if (IS_RUN_COMMAND_ERR(status))
349                         die("unable to run '%s'", argv[0]);
350                 exit(-status);
351         }
352         errno = ENOENT; /* as if we called execvp */
353
354         argv[0] = tmp;
355
356         strbuf_release(&cmd);
357 }
358
359 static int run_argv(int *argcp, const char ***argv)
360 {
361         int done_alias = 0;
362
363         while (1) {
364                 /* See if it's an internal command */
365                 handle_internal_command(*argcp, *argv);
366
367                 /* .. then try the external ones */
368                 execv_dashed_external(*argv);
369
370                 /* It could be an alias -- this works around the insanity
371                  * of overriding "perf log" with "perf show" by having
372                  * alias.log = show
373                  */
374                 if (done_alias || !handle_alias(argcp, argv))
375                         break;
376                 done_alias = 1;
377         }
378
379         return done_alias;
380 }
381
382 /* mini /proc/mounts parser: searching for "^blah /mount/point debugfs" */
383 static void get_debugfs_mntpt(void)
384 {
385         FILE *file;
386         char fs_type[100];
387         char debugfs[MAXPATHLEN];
388
389         /*
390          * try the standard location
391          */
392         if (valid_debugfs_mount("/sys/kernel/debug/") == 0) {
393                 strcpy(debugfs_mntpt, "/sys/kernel/debug/");
394                 return;
395         }
396
397         /*
398          * try the sane location
399          */
400         if (valid_debugfs_mount("/debug/") == 0) {
401                 strcpy(debugfs_mntpt, "/debug/");
402                 return;
403         }
404
405         /*
406          * give up and parse /proc/mounts
407          */
408         file = fopen("/proc/mounts", "r");
409         if (file == NULL)
410                 return;
411
412         while (fscanf(file, "%*s %"
413                       STR(MAXPATHLEN)
414                       "s %99s %*s %*d %*d\n",
415                       debugfs, fs_type) == 2) {
416                 if (strcmp(fs_type, "debugfs") == 0)
417                         break;
418         }
419         fclose(file);
420         if (strcmp(fs_type, "debugfs") == 0) {
421                 strncpy(debugfs_mntpt, debugfs, MAXPATHLEN);
422                 debugfs_mntpt[MAXPATHLEN - 1] = '\0';
423         }
424 }
425
426 int main(int argc, const char **argv)
427 {
428         const char *cmd;
429
430         cmd = perf_extract_argv0_path(argv[0]);
431         if (!cmd)
432                 cmd = "perf-help";
433         /* get debugfs mount point from /proc/mounts */
434         get_debugfs_mntpt();
435         /*
436          * "perf-xxxx" is the same as "perf xxxx", but we obviously:
437          *
438          *  - cannot take flags in between the "perf" and the "xxxx".
439          *  - cannot execute it externally (since it would just do
440          *    the same thing over again)
441          *
442          * So we just directly call the internal command handler, and
443          * die if that one cannot handle it.
444          */
445         if (!prefixcmp(cmd, "perf-")) {
446                 cmd += 5;
447                 argv[0] = cmd;
448                 handle_internal_command(argc, argv);
449                 die("cannot handle %s internally", cmd);
450         }
451
452         /* Look for flags.. */
453         argv++;
454         argc--;
455         handle_options(&argv, &argc, NULL);
456         commit_pager_choice();
457         set_debugfs_path();
458         if (argc > 0) {
459                 if (!prefixcmp(argv[0], "--"))
460                         argv[0] += 2;
461         } else {
462                 /* The user didn't specify a command; give them help */
463                 printf("\n usage: %s\n\n", perf_usage_string);
464                 list_common_cmds_help();
465                 printf("\n %s\n\n", perf_more_info_string);
466                 exit(1);
467         }
468         cmd = argv[0];
469
470         /*
471          * We use PATH to find perf commands, but we prepend some higher
472          * precidence paths: the "--exec-path" option, the PERF_EXEC_PATH
473          * environment, and the $(perfexecdir) from the Makefile at build
474          * time.
475          */
476         setup_path();
477
478         while (1) {
479                 static int done_help = 0;
480                 static int was_alias = 0;
481
482                 was_alias = run_argv(&argc, &argv);
483                 if (errno != ENOENT)
484                         break;
485
486                 if (was_alias) {
487                         fprintf(stderr, "Expansion of alias '%s' failed; "
488                                 "'%s' is not a perf-command\n",
489                                 cmd, argv[0]);
490                         exit(1);
491                 }
492                 if (!done_help) {
493                         cmd = argv[0] = help_unknown_cmd(cmd);
494                         done_help = 1;
495                 } else
496                         break;
497         }
498
499         fprintf(stderr, "Failed to run command '%s': %s\n",
500                 cmd, strerror(errno));
501
502         return 1;
503 }