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