perf.c 12.8 KB
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298 299 300 301 302 303 304 305 306 307 308 309 310 311 312 313 314 315 316 317 318 319 320 321 322 323 324 325 326 327 328 329 330 331 332 333 334 335 336 337 338 339 340 341 342 343 344 345 346 347 348 349 350 351 352 353 354 355 356 357 358 359 360 361 362 363 364 365 366 367 368 369 370 371 372 373 374 375 376 377 378 379 380 381 382 383 384 385 386 387 388 389 390 391 392 393 394 395 396 397 398 399 400 401 402 403 404 405 406 407 408 409 410 411 412 413 414 415 416 417 418 419 420 421 422 423 424 425 426 427 428 429 430 431 432 433 434 435 436 437 438 439 440 441 442 443 444 445 446 447 448 449 450 451 452 453 454 455 456 457 458 459 460 461 462 463 464 465 466 467 468 469 470 471 472 473 474 475 476 477 478 479 480 481 482 483 484 485 486 487 488 489 490 491 492 493 494 495 496 497 498 499 500 501 502 503 504 505 506 507 508 509 510 511 512 513 514 515 516 517 518 519 520 521 522 523 524 525 526 527 528 529 530 531 532 533 534 535 536 537 538 539 540 541 542 543 544 545 546 547 548 549 550 551
/*
 * perf.c
 *
 * Performance analysis utility.
 *
 * This is the main hub from which the sub-commands (perf stat,
 * perf top, perf record, perf report, etc.) are started.
 */
#include "builtin.h"

#include "util/exec_cmd.h"
#include "util/cache.h"
#include "util/quote.h"
#include "util/run-command.h"
#include "util/parse-events.h"
#include <api/fs/debugfs.h>
#include <pthread.h>

const char perf_usage_string[] =
	"perf [--version] [--help] COMMAND [ARGS]";

const char perf_more_info_string[] =
	"See 'perf help COMMAND' for more information on a specific command.";

int use_browser = -1;
static int use_pager = -1;
const char *input_name;

struct cmd_struct {
	const char *cmd;
	int (*fn)(int, const char **, const char *);
	int option;
};

static struct cmd_struct commands[] = {
	{ "buildid-cache", cmd_buildid_cache, 0 },
	{ "buildid-list", cmd_buildid_list, 0 },
	{ "diff",	cmd_diff,	0 },
	{ "evlist",	cmd_evlist,	0 },
	{ "help",	cmd_help,	0 },
	{ "list",	cmd_list,	0 },
	{ "record",	cmd_record,	0 },
	{ "report",	cmd_report,	0 },
	{ "bench",	cmd_bench,	0 },
	{ "stat",	cmd_stat,	0 },
	{ "timechart",	cmd_timechart,	0 },
	{ "top",	cmd_top,	0 },
	{ "annotate",	cmd_annotate,	0 },
	{ "version",	cmd_version,	0 },
	{ "script",	cmd_script,	0 },
	{ "sched",	cmd_sched,	0 },
#ifdef HAVE_LIBELF_SUPPORT
	{ "probe",	cmd_probe,	0 },
#endif
	{ "kmem",	cmd_kmem,	0 },
	{ "lock",	cmd_lock,	0 },
	{ "kvm",	cmd_kvm,	0 },
	{ "test",	cmd_test,	0 },
#ifdef HAVE_LIBAUDIT_SUPPORT
	{ "trace",	cmd_trace,	0 },
#endif
	{ "inject",	cmd_inject,	0 },
	{ "mem",	cmd_mem,	0 },
};

struct pager_config {
	const char *cmd;
	int val;
};

static int pager_command_config(const char *var, const char *value, void *data)
{
	struct pager_config *c = data;
	if (!prefixcmp(var, "pager.") && !strcmp(var + 6, c->cmd))
		c->val = perf_config_bool(var, value);
	return 0;
}

/* returns 0 for "no pager", 1 for "use pager", and -1 for "not specified" */
int check_pager_config(const char *cmd)
{
	struct pager_config c;
	c.cmd = cmd;
	c.val = -1;
	perf_config(pager_command_config, &c);
	return c.val;
}

static int browser_command_config(const char *var, const char *value, void *data)
{
	struct pager_config *c = data;
	if (!prefixcmp(var, "tui.") && !strcmp(var + 4, c->cmd))
		c->val = perf_config_bool(var, value);
	if (!prefixcmp(var, "gtk.") && !strcmp(var + 4, c->cmd))
		c->val = perf_config_bool(var, value) ? 2 : 0;
	return 0;
}

/*
 * returns 0 for "no tui", 1 for "use tui", 2 for "use gtk",
 * and -1 for "not specified"
 */
static int check_browser_config(const char *cmd)
{
	struct pager_config c;
	c.cmd = cmd;
	c.val = -1;
	perf_config(browser_command_config, &c);
	return c.val;
}

static void commit_pager_choice(void)
{
	switch (use_pager) {
	case 0:
		setenv("PERF_PAGER", "cat", 1);
		break;
	case 1:
		/* setup_pager(); */
		break;
	default:
		break;
	}
}

static int handle_options(const char ***argv, int *argc, int *envchanged)
{
	int handled = 0;

	while (*argc > 0) {
		const char *cmd = (*argv)[0];
		if (cmd[0] != '-')
			break;

		/*
		 * For legacy reasons, the "version" and "help"
		 * commands can be written with "--" prepended
		 * to make them look like flags.
		 */
		if (!strcmp(cmd, "--help") || !strcmp(cmd, "--version"))
			break;

		/*
		 * Check remaining flags.
		 */
		if (!prefixcmp(cmd, CMD_EXEC_PATH)) {
			cmd += strlen(CMD_EXEC_PATH);
			if (*cmd == '=')
				perf_set_argv_exec_path(cmd + 1);
			else {
				puts(perf_exec_path());
				exit(0);
			}
		} else if (!strcmp(cmd, "--html-path")) {
			puts(system_path(PERF_HTML_PATH));
			exit(0);
		} else if (!strcmp(cmd, "-p") || !strcmp(cmd, "--paginate")) {
			use_pager = 1;
		} else if (!strcmp(cmd, "--no-pager")) {
			use_pager = 0;
			if (envchanged)
				*envchanged = 1;
		} else if (!strcmp(cmd, "--perf-dir")) {
			if (*argc < 2) {
				fprintf(stderr, "No directory given for --perf-dir.\n");
				usage(perf_usage_string);
			}
			setenv(PERF_DIR_ENVIRONMENT, (*argv)[1], 1);
			if (envchanged)
				*envchanged = 1;
			(*argv)++;
			(*argc)--;
			handled++;
		} else if (!prefixcmp(cmd, CMD_PERF_DIR)) {
			setenv(PERF_DIR_ENVIRONMENT, cmd + strlen(CMD_PERF_DIR), 1);
			if (envchanged)
				*envchanged = 1;
		} else if (!strcmp(cmd, "--work-tree")) {
			if (*argc < 2) {
				fprintf(stderr, "No directory given for --work-tree.\n");
				usage(perf_usage_string);
			}
			setenv(PERF_WORK_TREE_ENVIRONMENT, (*argv)[1], 1);
			if (envchanged)
				*envchanged = 1;
			(*argv)++;
			(*argc)--;
		} else if (!prefixcmp(cmd, CMD_WORK_TREE)) {
			setenv(PERF_WORK_TREE_ENVIRONMENT, cmd + strlen(CMD_WORK_TREE), 1);
			if (envchanged)
				*envchanged = 1;
		} else if (!strcmp(cmd, "--debugfs-dir")) {
			if (*argc < 2) {
				fprintf(stderr, "No directory given for --debugfs-dir.\n");
				usage(perf_usage_string);
			}
			perf_debugfs_set_path((*argv)[1]);
			if (envchanged)
				*envchanged = 1;
			(*argv)++;
			(*argc)--;
		} else if (!prefixcmp(cmd, CMD_DEBUGFS_DIR)) {
			perf_debugfs_set_path(cmd + strlen(CMD_DEBUGFS_DIR));
			fprintf(stderr, "dir: %s\n", debugfs_mountpoint);
			if (envchanged)
				*envchanged = 1;
		} else if (!strcmp(cmd, "--list-cmds")) {
			unsigned int i;

			for (i = 0; i < ARRAY_SIZE(commands); i++) {
				struct cmd_struct *p = commands+i;
				printf("%s ", p->cmd);
			}
			exit(0);
		} else {
			fprintf(stderr, "Unknown option: %s\n", cmd);
			usage(perf_usage_string);
		}

		(*argv)++;
		(*argc)--;
		handled++;
	}
	return handled;
}

static int handle_alias(int *argcp, const char ***argv)
{
	int envchanged = 0, ret = 0, saved_errno = errno;
	int count, option_count;
	const char **new_argv;
	const char *alias_command;
	char *alias_string;

	alias_command = (*argv)[0];
	alias_string = alias_lookup(alias_command);
	if (alias_string) {
		if (alias_string[0] == '!') {
			if (*argcp > 1) {
				struct strbuf buf;

				strbuf_init(&buf, PATH_MAX);
				strbuf_addstr(&buf, alias_string);
				sq_quote_argv(&buf, (*argv) + 1, PATH_MAX);
				free(alias_string);
				alias_string = buf.buf;
			}
			ret = system(alias_string + 1);
			if (ret >= 0 && WIFEXITED(ret) &&
			    WEXITSTATUS(ret) != 127)
				exit(WEXITSTATUS(ret));
			die("Failed to run '%s' when expanding alias '%s'",
			    alias_string + 1, alias_command);
		}
		count = split_cmdline(alias_string, &new_argv);
		if (count < 0)
			die("Bad alias.%s string", alias_command);
		option_count = handle_options(&new_argv, &count, &envchanged);
		if (envchanged)
			die("alias '%s' changes environment variables\n"
				 "You can use '!perf' in the alias to do this.",
				 alias_command);
		memmove(new_argv - option_count, new_argv,
				count * sizeof(char *));
		new_argv -= option_count;

		if (count < 1)
			die("empty alias for %s", alias_command);

		if (!strcmp(alias_command, new_argv[0]))
			die("recursive alias: %s", alias_command);

		new_argv = realloc(new_argv, sizeof(char *) *
				    (count + *argcp + 1));
		/* insert after command name */
		memcpy(new_argv + count, *argv + 1, sizeof(char *) * *argcp);
		new_argv[count + *argcp] = NULL;

		*argv = new_argv;
		*argcp += count - 1;

		ret = 1;
	}

	errno = saved_errno;

	return ret;
}

const char perf_version_string[] = PERF_VERSION;

#define RUN_SETUP	(1<<0)
#define USE_PAGER	(1<<1)
/*
 * require working tree to be present -- anything uses this needs
 * RUN_SETUP for reading from the configuration file.
 */
#define NEED_WORK_TREE	(1<<2)

static int run_builtin(struct cmd_struct *p, int argc, const char **argv)
{
	int status;
	struct stat st;
	const char *prefix;

	prefix = NULL;
	if (p->option & RUN_SETUP)
		prefix = NULL; /* setup_perf_directory(); */

	if (use_browser == -1)
		use_browser = check_browser_config(p->cmd);

	if (use_pager == -1 && p->option & RUN_SETUP)
		use_pager = check_pager_config(p->cmd);
	if (use_pager == -1 && p->option & USE_PAGER)
		use_pager = 1;
	commit_pager_choice();

	status = p->fn(argc, argv, prefix);
	exit_browser(status);

	if (status)
		return status & 0xff;

	/* Somebody closed stdout? */
	if (fstat(fileno(stdout), &st))
		return 0;
	/* Ignore write errors for pipes and sockets.. */
	if (S_ISFIFO(st.st_mode) || S_ISSOCK(st.st_mode))
		return 0;

	status = 1;
	/* Check for ENOSPC and EIO errors.. */
	if (fflush(stdout)) {
		fprintf(stderr, "write failure on standard output: %s", strerror(errno));
		goto out;
	}
	if (ferror(stdout)) {
		fprintf(stderr, "unknown write failure on standard output");
		goto out;
	}
	if (fclose(stdout)) {
		fprintf(stderr, "close failed on standard output: %s", strerror(errno));
		goto out;
	}
	status = 0;
out:
	return status;
}

static void handle_internal_command(int argc, const char **argv)
{
	const char *cmd = argv[0];
	unsigned int i;
	static const char ext[] = STRIP_EXTENSION;

	if (sizeof(ext) > 1) {
		i = strlen(argv[0]) - strlen(ext);
		if (i > 0 && !strcmp(argv[0] + i, ext)) {
			char *argv0 = strdup(argv[0]);
			argv[0] = cmd = argv0;
			argv0[i] = '\0';
		}
	}

	/* Turn "perf cmd --help" into "perf help cmd" */
	if (argc > 1 && !strcmp(argv[1], "--help")) {
		argv[1] = argv[0];
		argv[0] = cmd = "help";
	}

	for (i = 0; i < ARRAY_SIZE(commands); i++) {
		struct cmd_struct *p = commands+i;
		if (strcmp(p->cmd, cmd))
			continue;
		exit(run_builtin(p, argc, argv));
	}
}

static void execv_dashed_external(const char **argv)
{
	struct strbuf cmd = STRBUF_INIT;
	const char *tmp;
	int status;

	strbuf_addf(&cmd, "perf-%s", argv[0]);

	/*
	 * argv[0] must be the perf command, but the argv array
	 * belongs to the caller, and may be reused in
	 * subsequent loop iterations. Save argv[0] and
	 * restore it on error.
	 */
	tmp = argv[0];
	argv[0] = cmd.buf;

	/*
	 * if we fail because the command is not found, it is
	 * OK to return. Otherwise, we just pass along the status code.
	 */
	status = run_command_v_opt(argv, 0);
	if (status != -ERR_RUN_COMMAND_EXEC) {
		if (IS_RUN_COMMAND_ERR(status))
			die("unable to run '%s'", argv[0]);
		exit(-status);
	}
	errno = ENOENT; /* as if we called execvp */

	argv[0] = tmp;

	strbuf_release(&cmd);
}

static int run_argv(int *argcp, const char ***argv)
{
	int done_alias = 0;

	while (1) {
		/* See if it's an internal command */
		handle_internal_command(*argcp, *argv);

		/* .. then try the external ones */
		execv_dashed_external(*argv);

		/* It could be an alias -- this works around the insanity
		 * of overriding "perf log" with "perf show" by having
		 * alias.log = show
		 */
		if (done_alias || !handle_alias(argcp, argv))
			break;
		done_alias = 1;
	}

	return done_alias;
}

static void pthread__block_sigwinch(void)
{
	sigset_t set;

	sigemptyset(&set);
	sigaddset(&set, SIGWINCH);
	pthread_sigmask(SIG_BLOCK, &set, NULL);
}

void pthread__unblock_sigwinch(void)
{
	sigset_t set;

	sigemptyset(&set);
	sigaddset(&set, SIGWINCH);
	pthread_sigmask(SIG_UNBLOCK, &set, NULL);
}

int main(int argc, const char **argv)
{
	const char *cmd;

	/* The page_size is placed in util object. */
	page_size = sysconf(_SC_PAGE_SIZE);

	cmd = perf_extract_argv0_path(argv[0]);
	if (!cmd)
		cmd = "perf-help";
	/* get debugfs mount point from /proc/mounts */
	perf_debugfs_mount(NULL);
	/*
	 * "perf-xxxx" is the same as "perf xxxx", but we obviously:
	 *
	 *  - cannot take flags in between the "perf" and the "xxxx".
	 *  - cannot execute it externally (since it would just do
	 *    the same thing over again)
	 *
	 * So we just directly call the internal command handler, and
	 * die if that one cannot handle it.
	 */
	if (!prefixcmp(cmd, "perf-")) {
		cmd += 5;
		argv[0] = cmd;
		handle_internal_command(argc, argv);
		fprintf(stderr, "cannot handle %s internally", cmd);
		goto out;
	}
#ifdef HAVE_LIBAUDIT_SUPPORT
	if (!prefixcmp(cmd, "trace")) {
		set_buildid_dir();
		setup_path();
		argv[0] = "trace";
		return cmd_trace(argc, argv, NULL);
	}
#endif
	/* Look for flags.. */
	argv++;
	argc--;
	handle_options(&argv, &argc, NULL);
	commit_pager_choice();
	set_buildid_dir();

	if (argc > 0) {
		if (!prefixcmp(argv[0], "--"))
			argv[0] += 2;
	} else {
		/* The user didn't specify a command; give them help */
		printf("\n usage: %s\n\n", perf_usage_string);
		list_common_cmds_help();
		printf("\n %s\n\n", perf_more_info_string);
		goto out;
	}
	cmd = argv[0];

	test_attr__init();

	/*
	 * We use PATH to find perf commands, but we prepend some higher
	 * precedence paths: the "--exec-path" option, the PERF_EXEC_PATH
	 * environment, and the $(perfexecdir) from the Makefile at build
	 * time.
	 */
	setup_path();
	/*
	 * Block SIGWINCH notifications so that the thread that wants it can
	 * unblock and get syscalls like select interrupted instead of waiting
	 * forever while the signal goes to some other non interested thread.
	 */
	pthread__block_sigwinch();

	while (1) {
		static int done_help;
		int was_alias = run_argv(&argc, &argv);

		if (errno != ENOENT)
			break;

		if (was_alias) {
			fprintf(stderr, "Expansion of alias '%s' failed; "
				"'%s' is not a perf-command\n",
				cmd, argv[0]);
			goto out;
		}
		if (!done_help) {
			cmd = argv[0] = help_unknown_cmd(cmd);
			done_help = 1;
		} else
			break;
	}

	fprintf(stderr, "Failed to run command '%s': %s\n",
		cmd, strerror(errno));
out:
	return 1;
}