root/tools/perf/perf.c

DEFINITIONS

1. pager_command_config
2. check_pager_config
3. browser_command_config
4. check_browser_config
5. commit_pager_choice
6. handle_options
7. run_builtin
8. handle_internal_command
9. execv_dashed_external
10. run_argv
11. pthread__block_sigwinch
12. pthread__unblock_sigwinch
13. libperf_print
14. main

   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 #include "perf.h"
  11 
  12 #include "util/build-id.h"
  13 #include "util/cache.h"
  14 #include "util/env.h"
  15 #include <internal/lib.h> // page_size
  16 #include <subcmd/exec-cmd.h>
  17 #include "util/config.h"
  18 #include <subcmd/run-command.h>
  19 #include "util/parse-events.h"
  20 #include <subcmd/parse-options.h>
  21 #include "util/bpf-loader.h"
  22 #include "util/debug.h"
  23 #include "util/event.h"
  24 #include "util/util.h" // usage()
  25 #include "ui/ui.h"
  26 #include "perf-sys.h"
  27 #include <api/fs/fs.h>
  28 #include <api/fs/tracing_path.h>
  29 #include <perf/core.h>
  30 #include <errno.h>
  31 #include <pthread.h>
  32 #include <signal.h>
  33 #include <stdlib.h>
  34 #include <time.h>
  35 #include <sys/types.h>
  36 #include <sys/stat.h>
  37 #include <unistd.h>
  38 #include <linux/kernel.h>
  39 #include <linux/string.h>
  40 #include <linux/zalloc.h>
  41 
  42 const char perf_usage_string[] =
  43         "perf [--version] [--help] [OPTIONS] COMMAND [ARGS]";
  44 
  45 const char perf_more_info_string[] =
  46         "See 'perf help COMMAND' for more information on a specific command.";
  47 
  48 static int use_pager = -1;
  49 const char *input_name;
  50 
  51 struct cmd_struct {
  52         const char *cmd;
  53         int (*fn)(int, const char **);
  54         int option;
  55 };
  56 
  57 static struct cmd_struct commands[] = {
  58         { "buildid-cache", cmd_buildid_cache, 0 },
  59         { "buildid-list", cmd_buildid_list, 0 },
  60         { "config",     cmd_config,     0 },
  61         { "c2c",        cmd_c2c,        0 },
  62         { "diff",       cmd_diff,       0 },
  63         { "evlist",     cmd_evlist,     0 },
  64         { "help",       cmd_help,       0 },
  65         { "kallsyms",   cmd_kallsyms,   0 },
  66         { "list",       cmd_list,       0 },
  67         { "record",     cmd_record,     0 },
  68         { "report",     cmd_report,     0 },
  69         { "bench",      cmd_bench,      0 },
  70         { "stat",       cmd_stat,       0 },
  71         { "timechart",  cmd_timechart,  0 },
  72         { "top",        cmd_top,        0 },
  73         { "annotate",   cmd_annotate,   0 },
  74         { "version",    cmd_version,    0 },
  75         { "script",     cmd_script,     0 },
  76         { "sched",      cmd_sched,      0 },
  77 #ifdef HAVE_LIBELF_SUPPORT
  78         { "probe",      cmd_probe,      0 },
  79 #endif
  80         { "kmem",       cmd_kmem,       0 },
  81         { "lock",       cmd_lock,       0 },
  82         { "kvm",        cmd_kvm,        0 },
  83         { "test",       cmd_test,       0 },
  84 #if defined(HAVE_LIBAUDIT_SUPPORT) || defined(HAVE_SYSCALL_TABLE_SUPPORT)
  85         { "trace",      cmd_trace,      0 },
  86 #endif
  87         { "inject",     cmd_inject,     0 },
  88         { "mem",        cmd_mem,        0 },
  89         { "data",       cmd_data,       0 },
  90         { "ftrace",     cmd_ftrace,     0 },
  91 };
  92 
  93 struct pager_config {
  94         const char *cmd;
  95         int val;
  96 };
  97 
  98 static int pager_command_config(const char *var, const char *value, void *data)
  99 {
 100         struct pager_config *c = data;
 101         if (strstarts(var, "pager.") && !strcmp(var + 6, c->cmd))
 102                 c->val = perf_config_bool(var, value);
 103         return 0;
 104 }
 105 
 106 /* returns 0 for "no pager", 1 for "use pager", and -1 for "not specified" */
 107 static int check_pager_config(const char *cmd)
 108 {
 109         int err;
 110         struct pager_config c;
 111         c.cmd = cmd;
 112         c.val = -1;
 113         err = perf_config(pager_command_config, &c);
 114         return err ?: c.val;
 115 }
 116 
 117 static int browser_command_config(const char *var, const char *value, void *data)
 118 {
 119         struct pager_config *c = data;
 120         if (strstarts(var, "tui.") && !strcmp(var + 4, c->cmd))
 121                 c->val = perf_config_bool(var, value);
 122         if (strstarts(var, "gtk.") && !strcmp(var + 4, c->cmd))
 123                 c->val = perf_config_bool(var, value) ? 2 : 0;
 124         return 0;
 125 }
 126 
 127 /*
 128  * returns 0 for "no tui", 1 for "use tui", 2 for "use gtk",
 129  * and -1 for "not specified"
 130  */
 131 static int check_browser_config(const char *cmd)
 132 {
 133         int err;
 134         struct pager_config c;
 135         c.cmd = cmd;
 136         c.val = -1;
 137         err = perf_config(browser_command_config, &c);
 138         return err ?: c.val;
 139 }
 140 
 141 static void commit_pager_choice(void)
 142 {
 143         switch (use_pager) {
 144         case 0:
 145                 setenv(PERF_PAGER_ENVIRONMENT, "cat", 1);
 146                 break;
 147         case 1:
 148                 /* setup_pager(); */
 149                 break;
 150         default:
 151                 break;
 152         }
 153 }
 154 
 155 struct option options[] = {
 156         OPT_ARGUMENT("help", "help"),
 157         OPT_ARGUMENT("version", "version"),
 158         OPT_ARGUMENT("exec-path", "exec-path"),
 159         OPT_ARGUMENT("html-path", "html-path"),
 160         OPT_ARGUMENT("paginate", "paginate"),
 161         OPT_ARGUMENT("no-pager", "no-pager"),
 162         OPT_ARGUMENT("debugfs-dir", "debugfs-dir"),
 163         OPT_ARGUMENT("buildid-dir", "buildid-dir"),
 164         OPT_ARGUMENT("list-cmds", "list-cmds"),
 165         OPT_ARGUMENT("list-opts", "list-opts"),
 166         OPT_ARGUMENT("debug", "debug"),
 167         OPT_END()
 168 };
 169 
 170 static int handle_options(const char ***argv, int *argc, int *envchanged)
 171 {
 172         int handled = 0;
 173 
 174         while (*argc > 0) {
 175                 const char *cmd = (*argv)[0];
 176                 if (cmd[0] != '-')
 177                         break;
 178 
 179                 /*
 180                  * For legacy reasons, the "version" and "help"
 181                  * commands can be written with "--" prepended
 182                  * to make them look like flags.
 183                  */
 184                 if (!strcmp(cmd, "--help") || !strcmp(cmd, "--version"))
 185                         break;
 186 
 187                 /*
 188                  * Shortcut for '-h' and '-v' options to invoke help
 189                  * and version command.
 190                  */
 191                 if (!strcmp(cmd, "-h")) {
 192                         (*argv)[0] = "--help";
 193                         break;
 194                 }
 195 
 196                 if (!strcmp(cmd, "-v")) {
 197                         (*argv)[0] = "--version";
 198                         break;
 199                 }
 200 
 201                 if (!strcmp(cmd, "-vv")) {
 202                         (*argv)[0] = "version";
 203                         version_verbose = 1;
 204                         break;
 205                 }
 206 
 207                 /*
 208                  * Check remaining flags.
 209                  */
 210                 if (strstarts(cmd, CMD_EXEC_PATH)) {
 211                         cmd += strlen(CMD_EXEC_PATH);
 212                         if (*cmd == '=')
 213                                 set_argv_exec_path(cmd + 1);
 214                         else {
 215                                 puts(get_argv_exec_path());
 216                                 exit(0);
 217                         }
 218                 } else if (!strcmp(cmd, "--html-path")) {
 219                         puts(system_path(PERF_HTML_PATH));
 220                         exit(0);
 221                 } else if (!strcmp(cmd, "-p") || !strcmp(cmd, "--paginate")) {
 222                         use_pager = 1;
 223                 } else if (!strcmp(cmd, "--no-pager")) {
 224                         use_pager = 0;
 225                         if (envchanged)
 226                                 *envchanged = 1;
 227                 } else if (!strcmp(cmd, "--debugfs-dir")) {
 228                         if (*argc < 2) {
 229                                 fprintf(stderr, "No directory given for --debugfs-dir.\n");
 230                                 usage(perf_usage_string);
 231                         }
 232                         tracing_path_set((*argv)[1]);
 233                         if (envchanged)
 234                                 *envchanged = 1;
 235                         (*argv)++;
 236                         (*argc)--;
 237                 } else if (!strcmp(cmd, "--buildid-dir")) {
 238                         if (*argc < 2) {
 239                                 fprintf(stderr, "No directory given for --buildid-dir.\n");
 240                                 usage(perf_usage_string);
 241                         }
 242                         set_buildid_dir((*argv)[1]);
 243                         if (envchanged)
 244                                 *envchanged = 1;
 245                         (*argv)++;
 246                         (*argc)--;
 247                 } else if (strstarts(cmd, CMD_DEBUGFS_DIR)) {
 248                         tracing_path_set(cmd + strlen(CMD_DEBUGFS_DIR));
 249                         fprintf(stderr, "dir: %s\n", tracing_path_mount());
 250                         if (envchanged)
 251                                 *envchanged = 1;
 252                 } else if (!strcmp(cmd, "--list-cmds")) {
 253                         unsigned int i;
 254 
 255                         for (i = 0; i < ARRAY_SIZE(commands); i++) {
 256                                 struct cmd_struct *p = commands+i;
 257                                 printf("%s ", p->cmd);
 258                         }
 259                         putchar('\n');
 260                         exit(0);
 261                 } else if (!strcmp(cmd, "--list-opts")) {
 262                         unsigned int i;
 263 
 264                         for (i = 0; i < ARRAY_SIZE(options)-1; i++) {
 265                                 struct option *p = options+i;
 266                                 printf("--%s ", p->long_name);
 267                         }
 268                         putchar('\n');
 269                         exit(0);
 270                 } else if (!strcmp(cmd, "--debug")) {
 271                         if (*argc < 2) {
 272                                 fprintf(stderr, "No variable specified for --debug.\n");
 273                                 usage(perf_usage_string);
 274                         }
 275                         if (perf_debug_option((*argv)[1]))
 276                                 usage(perf_usage_string);
 277 
 278                         (*argv)++;
 279                         (*argc)--;
 280                 } else {
 281                         fprintf(stderr, "Unknown option: %s\n", cmd);
 282                         usage(perf_usage_string);
 283                 }
 284 
 285                 (*argv)++;
 286                 (*argc)--;
 287                 handled++;
 288         }
 289         return handled;
 290 }
 291 
 292 #define RUN_SETUP       (1<<0)
 293 #define USE_PAGER       (1<<1)
 294 
 295 static int run_builtin(struct cmd_struct *p, int argc, const char **argv)
 296 {
 297         int status;
 298         struct stat st;
 299         char sbuf[STRERR_BUFSIZE];
 300 
 301         if (use_browser == -1)
 302                 use_browser = check_browser_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         perf_env__init(&perf_env);
 311         perf_env__set_cmdline(&perf_env, argc, argv);
 312         status = p->fn(argc, argv);
 313         perf_config__exit();
 314         exit_browser(status);
 315         perf_env__exit(&perf_env);
 316         bpf__clear();
 317 
 318         if (status)
 319                 return status & 0xff;
 320 
 321         /* Somebody closed stdout? */
 322         if (fstat(fileno(stdout), &st))
 323                 return 0;
 324         /* Ignore write errors for pipes and sockets.. */
 325         if (S_ISFIFO(st.st_mode) || S_ISSOCK(st.st_mode))
 326                 return 0;
 327 
 328         status = 1;
 329         /* Check for ENOSPC and EIO errors.. */
 330         if (fflush(stdout)) {
 331                 fprintf(stderr, "write failure on standard output: %s",
 332                         str_error_r(errno, sbuf, sizeof(sbuf)));
 333                 goto out;
 334         }
 335         if (ferror(stdout)) {
 336                 fprintf(stderr, "unknown write failure on standard output");
 337                 goto out;
 338         }
 339         if (fclose(stdout)) {
 340                 fprintf(stderr, "close failed on standard output: %s",
 341                         str_error_r(errno, sbuf, sizeof(sbuf)));
 342                 goto out;
 343         }
 344         status = 0;
 345 out:
 346         return status;
 347 }
 348 
 349 static void handle_internal_command(int argc, const char **argv)
 350 {
 351         const char *cmd = argv[0];
 352         unsigned int i;
 353 
 354         /* Turn "perf cmd --help" into "perf help cmd" */
 355         if (argc > 1 && !strcmp(argv[1], "--help")) {
 356                 argv[1] = argv[0];
 357                 argv[0] = cmd = "help";
 358         }
 359 
 360         for (i = 0; i < ARRAY_SIZE(commands); i++) {
 361                 struct cmd_struct *p = commands+i;
 362                 if (strcmp(p->cmd, cmd))
 363                         continue;
 364                 exit(run_builtin(p, argc, argv));
 365         }
 366 }
 367 
 368 static void execv_dashed_external(const char **argv)
 369 {
 370         char *cmd;
 371         const char *tmp;
 372         int status;
 373 
 374         if (asprintf(&cmd, "perf-%s", argv[0]) < 0)
 375                 goto do_die;
 376 
 377         /*
 378          * argv[0] must be the perf command, but the argv array
 379          * belongs to the caller, and may be reused in
 380          * subsequent loop iterations. Save argv[0] and
 381          * restore it on error.
 382          */
 383         tmp = argv[0];
 384         argv[0] = cmd;
 385 
 386         /*
 387          * if we fail because the command is not found, it is
 388          * OK to return. Otherwise, we just pass along the status code.
 389          */
 390         status = run_command_v_opt(argv, 0);
 391         if (status != -ERR_RUN_COMMAND_EXEC) {
 392                 if (IS_RUN_COMMAND_ERR(status)) {
 393 do_die:
 394                         pr_err("FATAL: unable to run '%s'", argv[0]);
 395                         status = -128;
 396                 }
 397                 exit(-status);
 398         }
 399         errno = ENOENT; /* as if we called execvp */
 400 
 401         argv[0] = tmp;
 402         zfree(&cmd);
 403 }
 404 
 405 static int run_argv(int *argcp, const char ***argv)
 406 {
 407         /* See if it's an internal command */
 408         handle_internal_command(*argcp, *argv);
 409 
 410         /* .. then try the external ones */
 411         execv_dashed_external(*argv);
 412         return 0;
 413 }
 414 
 415 static void pthread__block_sigwinch(void)
 416 {
 417         sigset_t set;
 418 
 419         sigemptyset(&set);
 420         sigaddset(&set, SIGWINCH);
 421         pthread_sigmask(SIG_BLOCK, &set, NULL);
 422 }
 423 
 424 void pthread__unblock_sigwinch(void)
 425 {
 426         sigset_t set;
 427 
 428         sigemptyset(&set);
 429         sigaddset(&set, SIGWINCH);
 430         pthread_sigmask(SIG_UNBLOCK, &set, NULL);
 431 }
 432 
 433 static int libperf_print(enum libperf_print_level level,
 434                          const char *fmt, va_list ap)
 435 {
 436         return eprintf(level, verbose, fmt, ap);
 437 }
 438 
 439 int main(int argc, const char **argv)
 440 {
 441         int err;
 442         const char *cmd;
 443         char sbuf[STRERR_BUFSIZE];
 444 
 445         /* libsubcmd init */
 446         exec_cmd_init("perf", PREFIX, PERF_EXEC_PATH, EXEC_PATH_ENVIRONMENT);
 447         pager_init(PERF_PAGER_ENVIRONMENT);
 448 
 449         libperf_init(libperf_print);
 450 
 451         cmd = extract_argv0_path(argv[0]);
 452         if (!cmd)
 453                 cmd = "perf-help";
 454 
 455         srandom(time(NULL));
 456 
 457         /* Setting $PERF_CONFIG makes perf read _only_ the given config file. */
 458         config_exclusive_filename = getenv("PERF_CONFIG");
 459 
 460         err = perf_config(perf_default_config, NULL);
 461         if (err)
 462                 return err;
 463         set_buildid_dir(NULL);
 464 
 465         /*
 466          * "perf-xxxx" is the same as "perf xxxx", but we obviously:
 467          *
 468          *  - cannot take flags in between the "perf" and the "xxxx".
 469          *  - cannot execute it externally (since it would just do
 470          *    the same thing over again)
 471          *
 472          * So we just directly call the internal command handler. If that one
 473          * fails to handle this, then maybe we just run a renamed perf binary
 474          * that contains a dash in its name. To handle this scenario, we just
 475          * fall through and ignore the "xxxx" part of the command string.
 476          */
 477         if (strstarts(cmd, "perf-")) {
 478                 cmd += 5;
 479                 argv[0] = cmd;
 480                 handle_internal_command(argc, argv);
 481                 /*
 482                  * If the command is handled, the above function does not
 483                  * return undo changes and fall through in such a case.
 484                  */
 485                 cmd -= 5;
 486                 argv[0] = cmd;
 487         }
 488         if (strstarts(cmd, "trace")) {
 489 #if defined(HAVE_LIBAUDIT_SUPPORT) || defined(HAVE_SYSCALL_TABLE_SUPPORT)
 490                 setup_path();
 491                 argv[0] = "trace";
 492                 return cmd_trace(argc, argv);
 493 #else
 494                 fprintf(stderr,
 495                         "trace command not available: missing audit-libs devel package at build time.\n");
 496                 goto out;
 497 #endif
 498         }
 499         /* Look for flags.. */
 500         argv++;
 501         argc--;
 502         handle_options(&argv, &argc, NULL);
 503         commit_pager_choice();
 504 
 505         if (argc > 0) {
 506                 if (strstarts(argv[0], "--"))
 507                         argv[0] += 2;
 508         } else {
 509                 /* The user didn't specify a command; give them help */
 510                 printf("\n usage: %s\n\n", perf_usage_string);
 511                 list_common_cmds_help();
 512                 printf("\n %s\n\n", perf_more_info_string);
 513                 goto out;
 514         }
 515         cmd = argv[0];
 516 
 517         test_attr__init();
 518 
 519         /*
 520          * We use PATH to find perf commands, but we prepend some higher
 521          * precedence paths: the "--exec-path" option, the PERF_EXEC_PATH
 522          * environment, and the $(perfexecdir) from the Makefile at build
 523          * time.
 524          */
 525         setup_path();
 526         /*
 527          * Block SIGWINCH notifications so that the thread that wants it can
 528          * unblock and get syscalls like select interrupted instead of waiting
 529          * forever while the signal goes to some other non interested thread.
 530          */
 531         pthread__block_sigwinch();
 532 
 533         perf_debug_setup();
 534 
 535         while (1) {
 536                 static int done_help;
 537 
 538                 run_argv(&argc, &argv);
 539 
 540                 if (errno != ENOENT)
 541                         break;
 542 
 543                 if (!done_help) {
 544                         cmd = argv[0] = help_unknown_cmd(cmd);
 545                         done_help = 1;
 546                 } else
 547                         break;
 548         }
 549 
 550         fprintf(stderr, "Failed to run command '%s': %s\n",
 551                 cmd, str_error_r(errno, sbuf, sizeof(sbuf)));
 552 out:
 553         return 1;
 554 }