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/debugfs.h"
  17 #include <pthread.h>
  18
  19 const char perf_usage_string[] =
  20         "perf [--version] [--help] COMMAND [ARGS]";
  21
  22 const char perf_more_info_string[] =
  23         "See 'perf help COMMAND' for more information on a specific command.";
  24
  25 int use_browser = -1;
  26 static int use_pager = -1;
  27
  28 struct cmd_struct {
  29         const char *cmd;
  30         int (*fn)(int, const char **, const char *);
  31         int option;
  32 };
  33
  34 static struct cmd_struct commands[] = {
  35         { "buildid-cache", cmd_buildid_cache, 0 },
  36         { "buildid-list", cmd_buildid_list, 0 },
  37         { "diff",       cmd_diff,       0 },
  38         { "evlist",     cmd_evlist,     0 },
  39         { "help",       cmd_help,       0 },
  40         { "list",       cmd_list,       0 },
  41         { "record",     cmd_record,     0 },
  42         { "report",     cmd_report,     0 },
  43         { "bench",      cmd_bench,      0 },
  44         { "stat",       cmd_stat,       0 },
  45         { "timechart",  cmd_timechart,  0 },
  46         { "top",        cmd_top,        0 },
  47         { "annotate",   cmd_annotate,   0 },
  48         { "version",    cmd_version,    0 },
  49         { "script",     cmd_script,     0 },
  50         { "sched",      cmd_sched,      0 },
  51 #ifndef NO_LIBELF_SUPPORT
  52         { "probe",      cmd_probe,      0 },
  53 #endif
  54         { "kmem",       cmd_kmem,       0 },
  55         { "lock",       cmd_lock,       0 },
  56         { "kvm",        cmd_kvm,        0 },
  57         { "test",       cmd_test,       0 },
  58         { "trace",      cmd_trace,      0 },
  59         { "inject",     cmd_inject,     0 },
  60 };
  61
  62 struct pager_config {
  63         const char *cmd;
  64         int val;
  65 };
  66
  67 static int pager_command_config(const char *var, const char *value, void *data)
  68 {
  69         struct pager_config *c = data;
  70         if (!prefixcmp(var, "pager.") && !strcmp(var + 6, c->cmd))
  71                 c->val = perf_config_bool(var, value);
  72         return 0;
  73 }
  74
  75 /* returns 0 for "no pager", 1 for "use pager", and -1 for "not specified" */
  76 int check_pager_config(const char *cmd)
  77 {
  78         struct pager_config c;
  79         c.cmd = cmd;
  80         c.val = -1;
  81         perf_config(pager_command_config, &c);
  82         return c.val;
  83 }
  84
  85 static int tui_command_config(const char *var, const char *value, void *data)
  86 {
  87         struct pager_config *c = data;
  88         if (!prefixcmp(var, "tui.") && !strcmp(var + 4, c->cmd))
  89                 c->val = perf_config_bool(var, value);
  90         return 0;
  91 }
  92
  93 /* returns 0 for "no tui", 1 for "use tui", and -1 for "not specified" */
  94 static int check_tui_config(const char *cmd)
  95 {
  96         struct pager_config c;
  97         c.cmd = cmd;
  98         c.val = -1;
  99         perf_config(tui_command_config, &c);
 100         return c.val;
 101 }
 102
 103 static void commit_pager_choice(void)
 104 {
 105         switch (use_pager) {
 106         case 0:
 107                 setenv("PERF_PAGER", "cat", 1);
 108                 break;
 109         case 1:
 110                 /* setup_pager(); */
 111                 break;
 112         default:
 113                 break;
 114         }
 115 }
 116
 117 static int handle_options(const char ***argv, int *argc, int *envchanged)
 118 {
 119         int handled = 0;
 120
 121         while (*argc > 0) {
 122                 const char *cmd = (*argv)[0];
 123                 if (cmd[0] != '-')
 124                         break;
 125
 126                 /*
 127                  * For legacy reasons, the "version" and "help"
 128                  * commands can be written with "--" prepended
 129                  * to make them look like flags.
 130                  */
 131                 if (!strcmp(cmd, "--help") || !strcmp(cmd, "--version"))
 132                         break;
 133
 134                 /*
 135                  * Check remaining flags.
 136                  */
 137                 if (!prefixcmp(cmd, CMD_EXEC_PATH)) {
 138                         cmd += strlen(CMD_EXEC_PATH);
 139                         if (*cmd == '=')
 140                                 perf_set_argv_exec_path(cmd + 1);
 141                         else {
 142                                 puts(perf_exec_path());
 143                                 exit(0);
 144                         }
 145                 } else if (!strcmp(cmd, "--html-path")) {
 146                         puts(system_path(PERF_HTML_PATH));
 147                         exit(0);
 148                 } else if (!strcmp(cmd, "-p") || !strcmp(cmd, "--paginate")) {
 149                         use_pager = 1;
 150                 } else if (!strcmp(cmd, "--no-pager")) {
 151                         use_pager = 0;
 152                         if (envchanged)
 153                                 *envchanged = 1;
 154                 } else if (!strcmp(cmd, "--perf-dir")) {
 155                         if (*argc < 2) {
 156                                 fprintf(stderr, "No directory given for --perf-dir.\n");
 157                                 usage(perf_usage_string);
 158                         }
 159                         setenv(PERF_DIR_ENVIRONMENT, (*argv)[1], 1);
 160                         if (envchanged)
 161                                 *envchanged = 1;
 162                         (*argv)++;
 163                         (*argc)--;
 164                         handled++;
 165                 } else if (!prefixcmp(cmd, CMD_PERF_DIR)) {
 166                         setenv(PERF_DIR_ENVIRONMENT, cmd + strlen(CMD_PERF_DIR), 1);
 167                         if (envchanged)
 168                                 *envchanged = 1;
 169                 } else if (!strcmp(cmd, "--work-tree")) {
 170                         if (*argc < 2) {
 171                                 fprintf(stderr, "No directory given for --work-tree.\n");
 172                                 usage(perf_usage_string);
 173                         }
 174                         setenv(PERF_WORK_TREE_ENVIRONMENT, (*argv)[1], 1);
 175                         if (envchanged)
 176                                 *envchanged = 1;
 177                         (*argv)++;
 178                         (*argc)--;
 179                 } else if (!prefixcmp(cmd, CMD_WORK_TREE)) {
 180                         setenv(PERF_WORK_TREE_ENVIRONMENT, cmd + strlen(CMD_WORK_TREE), 1);
 181                         if (envchanged)
 182                                 *envchanged = 1;
 183                 } else if (!strcmp(cmd, "--debugfs-dir")) {
 184                         if (*argc < 2) {
 185                                 fprintf(stderr, "No directory given for --debugfs-dir.\n");
 186                                 usage(perf_usage_string);
 187                         }
 188                         debugfs_set_path((*argv)[1]);
 189                         if (envchanged)
 190                                 *envchanged = 1;
 191                         (*argv)++;
 192                         (*argc)--;
 193                 } else if (!prefixcmp(cmd, CMD_DEBUGFS_DIR)) {
 194                         debugfs_set_path(cmd + strlen(CMD_DEBUGFS_DIR));
 195                         fprintf(stderr, "dir: %s\n", debugfs_mountpoint);
 196                         if (envchanged)
 197                                 *envchanged = 1;
 198                 } else if (!strcmp(cmd, "--list-cmds")) {
 199                         unsigned int i;
 200
 201                         for (i = 0; i < ARRAY_SIZE(commands); i++) {
 202                                 struct cmd_struct *p = commands+i;
 203                                 printf("%s ", p->cmd);
 204                         }
 205                         exit(0);
 206                 } else {
 207                         fprintf(stderr, "Unknown option: %s\n", cmd);
 208                         usage(perf_usage_string);
 209                 }
 210
 211                 (*argv)++;
 212                 (*argc)--;
 213                 handled++;
 214         }
 215         return handled;
 216 }
 217
 218 static int handle_alias(int *argcp, const char ***argv)
 219 {
 220         int envchanged = 0, ret = 0, saved_errno = errno;
 221         int count, option_count;
 222         const char **new_argv;
 223         const char *alias_command;
 224         char *alias_string;
 225
 226         alias_command = (*argv)[0];
 227         alias_string = alias_lookup(alias_command);
 228         if (alias_string) {
 229                 if (alias_string[0] == '!') {
 230                         if (*argcp > 1) {
 231                                 struct strbuf buf;
 232
 233                                 strbuf_init(&buf, PATH_MAX);
 234                                 strbuf_addstr(&buf, alias_string);
 235                                 sq_quote_argv(&buf, (*argv) + 1, PATH_MAX);
 236                                 free(alias_string);
 237                                 alias_string = buf.buf;
 238                         }
 239                         ret = system(alias_string + 1);
 240                         if (ret >= 0 && WIFEXITED(ret) &&
 241                             WEXITSTATUS(ret) != 127)
 242                                 exit(WEXITSTATUS(ret));
 243                         die("Failed to run '%s' when expanding alias '%s'",
 244                             alias_string + 1, alias_command);
 245                 }
 246                 count = split_cmdline(alias_string, &new_argv);
 247                 if (count < 0)
 248                         die("Bad alias.%s string", alias_command);
 249                 option_count = handle_options(&new_argv, &count, &envchanged);
 250                 if (envchanged)
 251                         die("alias '%s' changes environment variables\n"
 252                                  "You can use '!perf' in the alias to do this.",
 253                                  alias_command);
 254                 memmove(new_argv - option_count, new_argv,
 255                                 count * sizeof(char *));
 256                 new_argv -= option_count;
 257
 258                 if (count < 1)
 259                         die("empty alias for %s", alias_command);
 260
 261                 if (!strcmp(alias_command, new_argv[0]))
 262                         die("recursive alias: %s", alias_command);
 263
 264                 new_argv = realloc(new_argv, sizeof(char *) *
 265                                     (count + *argcp + 1));
 266                 /* insert after command name */
 267                 memcpy(new_argv + count, *argv + 1, sizeof(char *) * *argcp);
 268                 new_argv[count + *argcp] = NULL;
 269
 270                 *argv = new_argv;
 271                 *argcp += count - 1;
 272
 273                 ret = 1;
 274         }
 275
 276         errno = saved_errno;
 277
 278         return ret;
 279 }
 280
 281 const char perf_version_string[] = PERF_VERSION;
 282
 283 #define RUN_SETUP       (1<<0)
 284 #define USE_PAGER       (1<<1)
 285 /*
 286  * require working tree to be present -- anything uses this needs
 287  * RUN_SETUP for reading from the configuration file.
 288  */
 289 #define NEED_WORK_TREE  (1<<2)
 290
 291 static int run_builtin(struct cmd_struct *p, int argc, const char **argv)
 292 {
 293         int status;
 294         struct stat st;
 295         const char *prefix;
 296
 297         prefix = NULL;
 298         if (p->option & RUN_SETUP)
 299                 prefix = NULL; /* setup_perf_directory(); */
 300
 301         if (use_browser == -1)
 302                 use_browser = check_tui_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         status = p->fn(argc, argv, prefix);
 311         exit_browser(status);
 312
 313         if (status)
 314                 return status & 0xff;
 315
 316         /* Somebody closed stdout? */
 317         if (fstat(fileno(stdout), &st))
 318                 return 0;
 319         /* Ignore write errors for pipes and sockets.. */
 320         if (S_ISFIFO(st.st_mode) || S_ISSOCK(st.st_mode))
 321                 return 0;
 322
 323         /* Check for ENOSPC and EIO errors.. */
 324         if (fflush(stdout))
 325                 die("write failure on standard output: %s", strerror(errno));
 326         if (ferror(stdout))
 327                 die("unknown write failure on standard output");
 328         if (fclose(stdout))
 329                 die("close failed on standard output: %s", strerror(errno));
 330         return 0;
 331 }
 332
 333 static void handle_internal_command(int argc, const char **argv)
 334 {
 335         const char *cmd = argv[0];
 336         unsigned int i;
 337         static const char ext[] = STRIP_EXTENSION;
 338
 339         if (sizeof(ext) > 1) {
 340                 i = strlen(argv[0]) - strlen(ext);
 341                 if (i > 0 && !strcmp(argv[0] + i, ext)) {
 342                         char *argv0 = strdup(argv[0]);
 343                         argv[0] = cmd = argv0;
 344                         argv0[i] = '\0';
 345                 }
 346         }
 347
 348         /* Turn "perf cmd --help" into "perf help cmd" */
 349         if (argc > 1 && !strcmp(argv[1], "--help")) {
 350                 argv[1] = argv[0];
 351                 argv[0] = cmd = "help";
 352         }
 353
 354         for (i = 0; i < ARRAY_SIZE(commands); i++) {
 355                 struct cmd_struct *p = commands+i;
 356                 if (strcmp(p->cmd, cmd))
 357                         continue;
 358                 exit(run_builtin(p, argc, argv));
 359         }
 360 }
 361
 362 static void execv_dashed_external(const char **argv)
 363 {
 364         struct strbuf cmd = STRBUF_INIT;
 365         const char *tmp;
 366         int status;
 367
 368         strbuf_addf(&cmd, "perf-%s", argv[0]);
 369
 370         /*
 371          * argv[0] must be the perf command, but the argv array
 372          * belongs to the caller, and may be reused in
 373          * subsequent loop iterations. Save argv[0] and
 374          * restore it on error.
 375          */
 376         tmp = argv[0];
 377         argv[0] = cmd.buf;
 378
 379         /*
 380          * if we fail because the command is not found, it is
 381          * OK to return. Otherwise, we just pass along the status code.
 382          */
 383         status = run_command_v_opt(argv, 0);
 384         if (status != -ERR_RUN_COMMAND_EXEC) {
 385                 if (IS_RUN_COMMAND_ERR(status))
 386                         die("unable to run '%s'", argv[0]);
 387                 exit(-status);
 388         }
 389         errno = ENOENT; /* as if we called execvp */
 390
 391         argv[0] = tmp;
 392
 393         strbuf_release(&cmd);
 394 }
 395
 396 static int run_argv(int *argcp, const char ***argv)
 397 {
 398         int done_alias = 0;
 399
 400         while (1) {
 401                 /* See if it's an internal command */
 402                 handle_internal_command(*argcp, *argv);
 403
 404                 /* .. then try the external ones */
 405                 execv_dashed_external(*argv);
 406
 407                 /* It could be an alias -- this works around the insanity
 408                  * of overriding "perf log" with "perf show" by having
 409                  * alias.log = show
 410                  */
 411                 if (done_alias || !handle_alias(argcp, argv))
 412                         break;
 413                 done_alias = 1;
 414         }
 415
 416         return done_alias;
 417 }
 418
 419 static void pthread__block_sigwinch(void)
 420 {
 421         sigset_t set;
 422
 423         sigemptyset(&set);
 424         sigaddset(&set, SIGWINCH);
 425         pthread_sigmask(SIG_BLOCK, &set, NULL);
 426 }
 427
 428 void pthread__unblock_sigwinch(void)
 429 {
 430         sigset_t set;
 431
 432         sigemptyset(&set);
 433         sigaddset(&set, SIGWINCH);
 434         pthread_sigmask(SIG_UNBLOCK, &set, NULL);
 435 }
 436
 437 int main(int argc, const char **argv)
 438 {
 439         const char *cmd;
 440
 441         cmd = perf_extract_argv0_path(argv[0]);
 442         if (!cmd)
 443                 cmd = "perf-help";
 444         /* get debugfs mount point from /proc/mounts */
 445         debugfs_mount(NULL);
 446         /*
 447          * "perf-xxxx" is the same as "perf xxxx", but we obviously:
 448          *
 449          *  - cannot take flags in between the "perf" and the "xxxx".
 450          *  - cannot execute it externally (since it would just do
 451          *    the same thing over again)
 452          *
 453          * So we just directly call the internal command handler, and
 454          * die if that one cannot handle it.
 455          */
 456         if (!prefixcmp(cmd, "perf-")) {
 457                 cmd += 5;
 458                 argv[0] = cmd;
 459                 handle_internal_command(argc, argv);
 460                 die("cannot handle %s internally", cmd);
 461         }
 462
 463         /* Look for flags.. */
 464         argv++;
 465         argc--;
 466         handle_options(&argv, &argc, NULL);
 467         commit_pager_choice();
 468         set_buildid_dir();
 469
 470         if (argc > 0) {
 471                 if (!prefixcmp(argv[0], "--"))
 472                         argv[0] += 2;
 473         } else {
 474                 /* The user didn't specify a command; give them help */
 475                 printf("\n usage: %s\n\n", perf_usage_string);
 476                 list_common_cmds_help();
 477                 printf("\n %s\n\n", perf_more_info_string);
 478                 exit(1);
 479         }
 480         cmd = argv[0];
 481
 482         /*
 483          * We use PATH to find perf commands, but we prepend some higher
 484          * precedence paths: the "--exec-path" option, the PERF_EXEC_PATH
 485          * environment, and the $(perfexecdir) from the Makefile at build
 486          * time.
 487          */
 488         setup_path();
 489         /*
 490          * Block SIGWINCH notifications so that the thread that wants it can
 491          * unblock and get syscalls like select interrupted instead of waiting
 492          * forever while the signal goes to some other non interested thread.
 493          */
 494         pthread__block_sigwinch();
 495
 496         while (1) {
 497                 static int done_help;
 498                 static int was_alias;
 499
 500                 was_alias = run_argv(&argc, &argv);
 501                 if (errno != ENOENT)
 502                         break;
 503
 504                 if (was_alias) {
 505                         fprintf(stderr, "Expansion of alias '%s' failed; "
 506                                 "'%s' is not a perf-command\n",
 507                                 cmd, argv[0]);
 508                         exit(1);
 509                 }
 510                 if (!done_help) {
 511                         cmd = argv[0] = help_unknown_cmd(cmd);
 512                         done_help = 1;
 513                 } else
 514                         break;
 515         }
 516
 517         fprintf(stderr, "Failed to run command '%s': %s\n",
 518                 cmd, strerror(errno));
 519
 520         return 1;
 521 }