tools/perf/perf.c

   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
  34 const char perf_usage_string[] =
  35         "perf [--version] [--help] [OPTIONS] COMMAND [ARGS]";
  36
  37 const char perf_more_info_string[] =
  38         "See 'perf help COMMAND' for more information on a specific command.";
  39
  40 static int use_pager = -1;
  41 const char *input_name;
  42
  43 struct cmd_struct {
  44         const char *cmd;
  45         int (*fn)(int, const char **);
  46         int option;
  47 };
  48
  49 static 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)
  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
  85 struct pager_config {
  86         const char *cmd;
  87         int val;
  88 };
  89
  90 static 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" */
  99 static 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
 109 static 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  */
 123 static 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
 133 static 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
 147 struct 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
 162 static 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
 287 static 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;
 336 out:
 337         return status;
 338 }
 339
 340 static 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
 359 static 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)) {
 384 do_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
 396 static 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
 406 static 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
 415 void 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
 427 static 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
 434 int 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)
 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)));
 557 out:
 558         return 1;
 559 }