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/string.h" 17 18 const char perf_usage_string[] = 19 "perf [--version] [--help] COMMAND [ARGS]"; 20 21 const char perf_more_info_string[] = 22 "See 'perf help COMMAND' for more information on a specific command."; 23 24 static int use_pager = -1; 25 struct pager_config { 26 const char *cmd; 27 int val; 28 }; 29 30 static char debugfs_mntpt[MAXPATHLEN]; 31 32 static int pager_command_config(const char *var, const char *value, void *data) 33 { 34 struct pager_config *c = data; 35 if (!prefixcmp(var, "pager.") && !strcmp(var + 6, c->cmd)) 36 c->val = perf_config_bool(var, value); 37 return 0; 38 } 39 40 /* returns 0 for "no pager", 1 for "use pager", and -1 for "not specified" */ 41 int check_pager_config(const char *cmd) 42 { 43 struct pager_config c; 44 c.cmd = cmd; 45 c.val = -1; 46 perf_config(pager_command_config, &c); 47 return c.val; 48 } 49 50 static void commit_pager_choice(void) { 51 switch (use_pager) { 52 case 0: 53 setenv("PERF_PAGER", "cat", 1); 54 break; 55 case 1: 56 /* setup_pager(); */ 57 break; 58 default: 59 break; 60 } 61 } 62 63 static void set_debugfs_path(void) 64 { 65 char *path; 66 67 path = getenv(PERF_DEBUGFS_ENVIRONMENT); 68 snprintf(debugfs_path, MAXPATHLEN, "%s/%s", path ?: debugfs_mntpt, 69 "tracing/events"); 70 } 71 72 static int handle_options(const char*** argv, int* argc, int* envchanged) 73 { 74 int handled = 0; 75 76 while (*argc > 0) { 77 const char *cmd = (*argv)[0]; 78 if (cmd[0] != '-') 79 break; 80 81 /* 82 * For legacy reasons, the "version" and "help" 83 * commands can be written with "--" prepended 84 * to make them look like flags. 85 */ 86 if (!strcmp(cmd, "--help") || !strcmp(cmd, "--version")) 87 break; 88 89 /* 90 * Check remaining flags. 91 */ 92 if (!prefixcmp(cmd, "--exec-path")) { 93 cmd += 11; 94 if (*cmd == '=') 95 perf_set_argv_exec_path(cmd + 1); 96 else { 97 puts(perf_exec_path()); 98 exit(0); 99 } 100 } else if (!strcmp(cmd, "--html-path")) { 101 puts(system_path(PERF_HTML_PATH)); 102 exit(0); 103 } else if (!strcmp(cmd, "-p") || !strcmp(cmd, "--paginate")) { 104 use_pager = 1; 105 } else if (!strcmp(cmd, "--no-pager")) { 106 use_pager = 0; 107 if (envchanged) 108 *envchanged = 1; 109 } else if (!strcmp(cmd, "--perf-dir")) { 110 if (*argc < 2) { 111 fprintf(stderr, "No directory given for --perf-dir.\n" ); 112 usage(perf_usage_string); 113 } 114 setenv(PERF_DIR_ENVIRONMENT, (*argv)[1], 1); 115 if (envchanged) 116 *envchanged = 1; 117 (*argv)++; 118 (*argc)--; 119 handled++; 120 } else if (!prefixcmp(cmd, "--perf-dir=")) { 121 setenv(PERF_DIR_ENVIRONMENT, cmd + 10, 1); 122 if (envchanged) 123 *envchanged = 1; 124 } else if (!strcmp(cmd, "--work-tree")) { 125 if (*argc < 2) { 126 fprintf(stderr, "No directory given for --work-tree.\n" ); 127 usage(perf_usage_string); 128 } 129 setenv(PERF_WORK_TREE_ENVIRONMENT, (*argv)[1], 1); 130 if (envchanged) 131 *envchanged = 1; 132 (*argv)++; 133 (*argc)--; 134 } else if (!prefixcmp(cmd, "--work-tree=")) { 135 setenv(PERF_WORK_TREE_ENVIRONMENT, cmd + 12, 1); 136 if (envchanged) 137 *envchanged = 1; 138 } else if (!strcmp(cmd, "--debugfs-dir")) { 139 if (*argc < 2) { 140 fprintf(stderr, "No directory given for --debugfs-dir.\n"); 141 usage(perf_usage_string); 142 } 143 strncpy(debugfs_mntpt, (*argv)[1], MAXPATHLEN); 144 debugfs_mntpt[MAXPATHLEN - 1] = '\0'; 145 if (envchanged) 146 *envchanged = 1; 147 (*argv)++; 148 (*argc)--; 149 } else if (!prefixcmp(cmd, "--debugfs-dir=")) { 150 strncpy(debugfs_mntpt, cmd + 14, MAXPATHLEN); 151 debugfs_mntpt[MAXPATHLEN - 1] = '\0'; 152 if (envchanged) 153 *envchanged = 1; 154 } else { 155 fprintf(stderr, "Unknown option: %s\n", cmd); 156 usage(perf_usage_string); 157 } 158 159 (*argv)++; 160 (*argc)--; 161 handled++; 162 } 163 return handled; 164 } 165 166 static int handle_alias(int *argcp, const char ***argv) 167 { 168 int envchanged = 0, ret = 0, saved_errno = errno; 169 int count, option_count; 170 const char** new_argv; 171 const char *alias_command; 172 char *alias_string; 173 174 alias_command = (*argv)[0]; 175 alias_string = alias_lookup(alias_command); 176 if (alias_string) { 177 if (alias_string[0] == '!') { 178 if (*argcp > 1) { 179 struct strbuf buf; 180 181 strbuf_init(&buf, PATH_MAX); 182 strbuf_addstr(&buf, alias_string); 183 sq_quote_argv(&buf, (*argv) + 1, PATH_MAX); 184 free(alias_string); 185 alias_string = buf.buf; 186 } 187 ret = system(alias_string + 1); 188 if (ret >= 0 && WIFEXITED(ret) && 189 WEXITSTATUS(ret) != 127) 190 exit(WEXITSTATUS(ret)); 191 die("Failed to run '%s' when expanding alias '%s'", 192 alias_string + 1, alias_command); 193 } 194 count = split_cmdline(alias_string, &new_argv); 195 if (count < 0) 196 die("Bad alias.%s string", alias_command); 197 option_count = handle_options(&new_argv, &count, &envchanged); 198 if (envchanged) 199 die("alias '%s' changes environment variables\n" 200 "You can use '!perf' in the alias to do this.", 201 alias_command); 202 memmove(new_argv - option_count, new_argv, 203 count * sizeof(char *)); 204 new_argv -= option_count; 205 206 if (count < 1) 207 die("empty alias for %s", alias_command); 208 209 if (!strcmp(alias_command, new_argv[0])) 210 die("recursive alias: %s", alias_command); 211 212 new_argv = realloc(new_argv, sizeof(char*) * 213 (count + *argcp + 1)); 214 /* insert after command name */ 215 memcpy(new_argv + count, *argv + 1, sizeof(char*) * *argcp); 216 new_argv[count+*argcp] = NULL; 217 218 *argv = new_argv; 219 *argcp += count - 1; 220 221 ret = 1; 222 } 223 224 errno = saved_errno; 225 226 return ret; 227 } 228 229 const char perf_version_string[] = PERF_VERSION; 230 231 #define RUN_SETUP (1<<0) 232 #define USE_PAGER (1<<1) 233 /* 234 * require working tree to be present -- anything uses this needs 235 * RUN_SETUP for reading from the configuration file. 236 */ 237 #define NEED_WORK_TREE (1<<2) 238 239 struct cmd_struct { 240 const char *cmd; 241 int (*fn)(int, const char **, const char *); 242 int option; 243 }; 244 245 static int run_builtin(struct cmd_struct *p, int argc, const char **argv) 246 { 247 int status; 248 struct stat st; 249 const char *prefix; 250 251 prefix = NULL; 252 if (p->option & RUN_SETUP) 253 prefix = NULL; /* setup_perf_directory(); */ 254 255 if (use_pager == -1 && p->option & RUN_SETUP) 256 use_pager = check_pager_config(p->cmd); 257 if (use_pager == -1 && p->option & USE_PAGER) 258 use_pager = 1; 259 commit_pager_choice(); 260 set_debugfs_path(); 261 262 status = p->fn(argc, argv, prefix); 263 if (status) 264 return status & 0xff; 265 266 /* Somebody closed stdout? */ 267 if (fstat(fileno(stdout), &st)) 268 return 0; 269 /* Ignore write errors for pipes and sockets.. */ 270 if (S_ISFIFO(st.st_mode) || S_ISSOCK(st.st_mode)) 271 return 0; 272 273 /* Check for ENOSPC and EIO errors.. */ 274 if (fflush(stdout)) 275 die("write failure on standard output: %s", strerror(errno)); 276 if (ferror(stdout)) 277 die("unknown write failure on standard output"); 278 if (fclose(stdout)) 279 die("close failed on standard output: %s", strerror(errno)); 280 return 0; 281 } 282 283 static void handle_internal_command(int argc, const char **argv) 284 { 285 const char *cmd = argv[0]; 286 static struct cmd_struct commands[] = { 287 { "help", cmd_help, 0 }, 288 { "list", cmd_list, 0 }, 289 { "record", cmd_record, 0 }, 290 { "report", cmd_report, 0 }, 291 { "stat", cmd_stat, 0 }, 292 { "top", cmd_top, 0 }, 293 { "annotate", cmd_annotate, 0 }, 294 { "version", cmd_version, 0 }, 295 { "trace", cmd_trace, 0 }, 296 }; 297 unsigned int i; 298 static const char ext[] = STRIP_EXTENSION; 299 300 if (sizeof(ext) > 1) { 301 i = strlen(argv[0]) - strlen(ext); 302 if (i > 0 && !strcmp(argv[0] + i, ext)) { 303 char *argv0 = strdup(argv[0]); 304 argv[0] = cmd = argv0; 305 argv0[i] = '\0'; 306 } 307 } 308 309 /* Turn "perf cmd --help" into "perf help cmd" */ 310 if (argc > 1 && !strcmp(argv[1], "--help")) { 311 argv[1] = argv[0]; 312 argv[0] = cmd = "help"; 313 } 314 315 for (i = 0; i < ARRAY_SIZE(commands); i++) { 316 struct cmd_struct *p = commands+i; 317 if (strcmp(p->cmd, cmd)) 318 continue; 319 exit(run_builtin(p, argc, argv)); 320 } 321 } 322 323 static void execv_dashed_external(const char **argv) 324 { 325 struct strbuf cmd = STRBUF_INIT; 326 const char *tmp; 327 int status; 328 329 strbuf_addf(&cmd, "perf-%s", argv[0]); 330 331 /* 332 * argv[0] must be the perf command, but the argv array 333 * belongs to the caller, and may be reused in 334 * subsequent loop iterations. Save argv[0] and 335 * restore it on error. 336 */ 337 tmp = argv[0]; 338 argv[0] = cmd.buf; 339 340 /* 341 * if we fail because the command is not found, it is 342 * OK to return. Otherwise, we just pass along the status code. 343 */ 344 status = run_command_v_opt(argv, 0); 345 if (status != -ERR_RUN_COMMAND_EXEC) { 346 if (IS_RUN_COMMAND_ERR(status)) 347 die("unable to run '%s'", argv[0]); 348 exit(-status); 349 } 350 errno = ENOENT; /* as if we called execvp */ 351 352 argv[0] = tmp; 353 354 strbuf_release(&cmd); 355 } 356 357 static int run_argv(int *argcp, const char ***argv) 358 { 359 int done_alias = 0; 360 361 while (1) { 362 /* See if it's an internal command */ 363 handle_internal_command(*argcp, *argv); 364 365 /* .. then try the external ones */ 366 execv_dashed_external(*argv); 367 368 /* It could be an alias -- this works around the insanity 369 * of overriding "perf log" with "perf show" by having 370 * alias.log = show 371 */ 372 if (done_alias || !handle_alias(argcp, argv)) 373 break; 374 done_alias = 1; 375 } 376 377 return done_alias; 378 } 379 380 /* mini /proc/mounts parser: searching for "^blah /mount/point debugfs" */ 381 static void get_debugfs_mntpt(void) 382 { 383 FILE *file; 384 char fs_type[100]; 385 char debugfs[MAXPATHLEN]; 386 387 /* 388 * try the standard location 389 */ 390 if (valid_debugfs_mount("/sys/kernel/debug/") == 0) { 391 strcpy(debugfs_mntpt, "/sys/kernel/debug/"); 392 return; 393 } 394 395 /* 396 * try the sane location 397 */ 398 if (valid_debugfs_mount("/debug/") == 0) { 399 strcpy(debugfs_mntpt, "/debug/"); 400 return; 401 } 402 403 /* 404 * give up and parse /proc/mounts 405 */ 406 file = fopen("/proc/mounts", "r"); 407 if (file == NULL) 408 return; 409 410 while (fscanf(file, "%*s %" 411 STR(MAXPATHLEN) 412 "s %99s %*s %*d %*d\n", 413 debugfs, fs_type) == 2) { 414 if (strcmp(fs_type, "debugfs") == 0) 415 break; 416 } 417 fclose(file); 418 if (strcmp(fs_type, "debugfs") == 0) { 419 strncpy(debugfs_mntpt, debugfs, MAXPATHLEN); 420 debugfs_mntpt[MAXPATHLEN - 1] = '\0'; 421 } 422 } 423 424 int main(int argc, const char **argv) 425 { 426 const char *cmd; 427 428 cmd = perf_extract_argv0_path(argv[0]); 429 if (!cmd) 430 cmd = "perf-help"; 431 /* get debugfs mount point from /proc/mounts */ 432 get_debugfs_mntpt(); 433 /* 434 * "perf-xxxx" is the same as "perf xxxx", but we obviously: 435 * 436 * - cannot take flags in between the "perf" and the "xxxx". 437 * - cannot execute it externally (since it would just do 438 * the same thing over again) 439 * 440 * So we just directly call the internal command handler, and 441 * die if that one cannot handle it. 442 */ 443 if (!prefixcmp(cmd, "perf-")) { 444 cmd += 5; 445 argv[0] = cmd; 446 handle_internal_command(argc, argv); 447 die("cannot handle %s internally", cmd); 448 } 449 450 /* Look for flags.. */ 451 argv++; 452 argc--; 453 handle_options(&argv, &argc, NULL); 454 commit_pager_choice(); 455 set_debugfs_path(); 456 if (argc > 0) { 457 if (!prefixcmp(argv[0], "--")) 458 argv[0] += 2; 459 } else { 460 /* The user didn't specify a command; give them help */ 461 printf("\n usage: %s\n\n", perf_usage_string); 462 list_common_cmds_help(); 463 printf("\n %s\n\n", perf_more_info_string); 464 exit(1); 465 } 466 cmd = argv[0]; 467 468 /* 469 * We use PATH to find perf commands, but we prepend some higher 470 * precidence paths: the "--exec-path" option, the PERF_EXEC_PATH 471 * environment, and the $(perfexecdir) from the Makefile at build 472 * time. 473 */ 474 setup_path(); 475 476 while (1) { 477 static int done_help = 0; 478 static int was_alias = 0; 479 480 was_alias = run_argv(&argc, &argv); 481 if (errno != ENOENT) 482 break; 483 484 if (was_alias) { 485 fprintf(stderr, "Expansion of alias '%s' failed; " 486 "'%s' is not a perf-command\n", 487 cmd, argv[0]); 488 exit(1); 489 } 490 if (!done_help) { 491 cmd = argv[0] = help_unknown_cmd(cmd); 492 done_help = 1; 493 } else 494 break; 495 } 496 497 fprintf(stderr, "Failed to run command '%s': %s\n", 498 cmd, strerror(errno)); 499 500 return 1; 501 } 502