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