event.c 20.8 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 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298 299 300 301 302 303 304 305 306 307 308 309 310 311 312 313 314 315 316 317 318 319 320 321 322 323 324 325 326 327 328 329 330 331 332 333 334 335 336 337 338 339 340 341 342 343 344 345 346 347 348 349 350 351 352 353 354 355 356 357 358 359 360 361 362 363 364 365 366 367 368 369 370 371 372 373 374 375 376 377 378 379 380 381 382 383 384 385 386 387 388 389 390 391 392 393 394 395 396 397 398 399 400 401 402 403 404 405 406 407 408 409 410 411 412 413 414 415 416 417 418 419 420 421 422 423 424 425 426 427 428 429 430 431 432 433 434 435 436 437 438 439 440 441 442 443 444 445 446 447 448 449 450 451 452 453 454 455 456 457 458 459 460 461 462 463 464 465 466 467 468 469 470 471 472 473 474 475 476 477 478 479 480 481 482 483 484 485 486 487 488 489 490 491 492 493 494 495 496 497 498 499 500 501 502 503 504 505 506 507 508 509 510 511 512 513 514 515 516 517 518 519 520 521 522 523 524 525 526 527 528 529 530 531 532 533 534 535 536 537 538 539 540 541 542 543 544 545 546 547 548 549 550 551 552 553 554 555 556 557 558 559 560 561 562 563 564 565 566 567 568 569 570 571 572 573 574 575 576 577 578 579 580 581 582 583 584 585 586 587 588 589 590 591 592 593 594 595 596 597 598 599 600 601 602 603 604 605 606 607 608 609 610 611 612 613 614 615 616 617 618 619 620 621 622 623 624 625 626 627 628 629 630 631 632 633 634 635 636 637 638 639 640 641 642 643 644 645 646 647 648 649 650 651 652 653 654 655 656 657 658 659 660 661 662 663 664 665 666 667 668 669 670 671 672 673 674 675 676 677 678 679 680 681 682 683 684 685 686 687 688 689 690 691 692 693 694 695 696 697 698 699 700 701 702 703 704 705 706 707 708 709 710 711 712 713 714 715 716 717 718 719 720 721 722 723 724 725 726 727 728 729 730 731 732 733 734 735 736 737 738 739 740 741 742 743 744 745 746 747 748 749 750 751 752 753 754 755 756 757 758 759 760 761 762 763 764 765 766 767 768 769 770 771 772 773 774 775 776 777 778 779 780 781 782 783 784 785 786 787 788 789 790 791 792 793 794 795 796 797 798 799 800 801 802 803 804 805 806 807 808 809
#include <linux/types.h>
#include "event.h"
#include "debug.h"
#include "session.h"
#include "sort.h"
#include "string.h"
#include "strlist.h"
#include "thread.h"
#include "thread_map.h"

static const char *perf_event__names[] = {
	[0]					= "TOTAL",
	[PERF_RECORD_MMAP]			= "MMAP",
	[PERF_RECORD_LOST]			= "LOST",
	[PERF_RECORD_COMM]			= "COMM",
	[PERF_RECORD_EXIT]			= "EXIT",
	[PERF_RECORD_THROTTLE]			= "THROTTLE",
	[PERF_RECORD_UNTHROTTLE]		= "UNTHROTTLE",
	[PERF_RECORD_FORK]			= "FORK",
	[PERF_RECORD_READ]			= "READ",
	[PERF_RECORD_SAMPLE]			= "SAMPLE",
	[PERF_RECORD_HEADER_ATTR]		= "ATTR",
	[PERF_RECORD_HEADER_EVENT_TYPE]		= "EVENT_TYPE",
	[PERF_RECORD_HEADER_TRACING_DATA]	= "TRACING_DATA",
	[PERF_RECORD_HEADER_BUILD_ID]		= "BUILD_ID",
	[PERF_RECORD_FINISHED_ROUND]		= "FINISHED_ROUND",
};

const char *perf_event__name(unsigned int id)
{
	if (id >= ARRAY_SIZE(perf_event__names))
		return "INVALID";
	if (!perf_event__names[id])
		return "UNKNOWN";
	return perf_event__names[id];
}

int perf_sample_size(u64 sample_type)
{
	u64 mask = sample_type & PERF_SAMPLE_MASK;
	int size = 0;
	int i;

	for (i = 0; i < 64; i++) {
		if (mask & (1UL << i))
			size++;
	}

	size *= sizeof(u64);

	return size;
}

static struct perf_sample synth_sample = {
	.pid	   = -1,
	.tid	   = -1,
	.time	   = -1,
	.stream_id = -1,
	.cpu	   = -1,
	.period	   = 1,
};

static pid_t perf_event__synthesize_comm(union perf_event *event, pid_t pid,
					 int full, perf_event__handler_t process,
					 struct perf_session *session)
{
	char filename[PATH_MAX];
	char bf[BUFSIZ];
	FILE *fp;
	size_t size = 0;
	DIR *tasks;
	struct dirent dirent, *next;
	pid_t tgid = 0;

	snprintf(filename, sizeof(filename), "/proc/%d/status", pid);

	fp = fopen(filename, "r");
	if (fp == NULL) {
out_race:
		/*
		 * We raced with a task exiting - just return:
		 */
		pr_debug("couldn't open %s\n", filename);
		return 0;
	}

	memset(&event->comm, 0, sizeof(event->comm));

	while (!event->comm.comm[0] || !event->comm.pid) {
		if (fgets(bf, sizeof(bf), fp) == NULL) {
			pr_warning("couldn't get COMM and pgid, malformed %s\n", filename);
			goto out;
		}

		if (memcmp(bf, "Name:", 5) == 0) {
			char *name = bf + 5;
			while (*name && isspace(*name))
				++name;
			size = strlen(name) - 1;
			memcpy(event->comm.comm, name, size++);
		} else if (memcmp(bf, "Tgid:", 5) == 0) {
			char *tgids = bf + 5;
			while (*tgids && isspace(*tgids))
				++tgids;
			tgid = event->comm.pid = atoi(tgids);
		}
	}

	event->comm.header.type = PERF_RECORD_COMM;
	size = ALIGN(size, sizeof(u64));
	memset(event->comm.comm + size, 0, session->id_hdr_size);
	event->comm.header.size = (sizeof(event->comm) -
				(sizeof(event->comm.comm) - size) +
				session->id_hdr_size);
	if (!full) {
		event->comm.tid = pid;

		process(event, &synth_sample, session);
		goto out;
	}

	snprintf(filename, sizeof(filename), "/proc/%d/task", pid);

	tasks = opendir(filename);
	if (tasks == NULL)
		goto out_race;

	while (!readdir_r(tasks, &dirent, &next) && next) {
		char *end;
		pid = strtol(dirent.d_name, &end, 10);
		if (*end)
			continue;

		event->comm.tid = pid;

		process(event, &synth_sample, session);
	}

	closedir(tasks);
out:
	fclose(fp);

	return tgid;
}

static int perf_event__synthesize_mmap_events(union perf_event *event,
					      pid_t pid, pid_t tgid,
					      perf_event__handler_t process,
					      struct perf_session *session)
{
	char filename[PATH_MAX];
	FILE *fp;

	snprintf(filename, sizeof(filename), "/proc/%d/maps", pid);

	fp = fopen(filename, "r");
	if (fp == NULL) {
		/*
		 * We raced with a task exiting - just return:
		 */
		pr_debug("couldn't open %s\n", filename);
		return -1;
	}

	event->header.type = PERF_RECORD_MMAP;
	/*
	 * Just like the kernel, see __perf_event_mmap in kernel/perf_event.c
	 */
	event->header.misc = PERF_RECORD_MISC_USER;

	while (1) {
		char bf[BUFSIZ], *pbf = bf;
		int n;
		size_t size;
		if (fgets(bf, sizeof(bf), fp) == NULL)
			break;

		/* 00400000-0040c000 r-xp 00000000 fd:01 41038  /bin/cat */
		n = hex2u64(pbf, &event->mmap.start);
		if (n < 0)
			continue;
		pbf += n + 1;
		n = hex2u64(pbf, &event->mmap.len);
		if (n < 0)
			continue;
		pbf += n + 3;
		if (*pbf == 'x') { /* vm_exec */
			char *execname = strchr(bf, '/');

			/* Catch VDSO */
			if (execname == NULL)
				execname = strstr(bf, "[vdso]");

			if (execname == NULL)
				continue;

			pbf += 3;
			n = hex2u64(pbf, &event->mmap.pgoff);

			size = strlen(execname);
			execname[size - 1] = '\0'; /* Remove \n */
			memcpy(event->mmap.filename, execname, size);
			size = ALIGN(size, sizeof(u64));
			event->mmap.len -= event->mmap.start;
			event->mmap.header.size = (sizeof(event->mmap) -
					        (sizeof(event->mmap.filename) - size));
			memset(event->mmap.filename + size, 0, session->id_hdr_size);
			event->mmap.header.size += session->id_hdr_size;
			event->mmap.pid = tgid;
			event->mmap.tid = pid;

			process(event, &synth_sample, session);
		}
	}

	fclose(fp);
	return 0;
}

int perf_event__synthesize_modules(perf_event__handler_t process,
				   struct perf_session *session,
				   struct machine *machine)
{
	struct rb_node *nd;
	struct map_groups *kmaps = &machine->kmaps;
	union perf_event *event = zalloc((sizeof(event->mmap) +
					  session->id_hdr_size));
	if (event == NULL) {
		pr_debug("Not enough memory synthesizing mmap event "
			 "for kernel modules\n");
		return -1;
	}

	event->header.type = PERF_RECORD_MMAP;

	/*
	 * kernel uses 0 for user space maps, see kernel/perf_event.c
	 * __perf_event_mmap
	 */
	if (machine__is_host(machine))
		event->header.misc = PERF_RECORD_MISC_KERNEL;
	else
		event->header.misc = PERF_RECORD_MISC_GUEST_KERNEL;

	for (nd = rb_first(&kmaps->maps[MAP__FUNCTION]);
	     nd; nd = rb_next(nd)) {
		size_t size;
		struct map *pos = rb_entry(nd, struct map, rb_node);

		if (pos->dso->kernel)
			continue;

		size = ALIGN(pos->dso->long_name_len + 1, sizeof(u64));
		event->mmap.header.type = PERF_RECORD_MMAP;
		event->mmap.header.size = (sizeof(event->mmap) -
				        (sizeof(event->mmap.filename) - size));
		memset(event->mmap.filename + size, 0, session->id_hdr_size);
		event->mmap.header.size += session->id_hdr_size;
		event->mmap.start = pos->start;
		event->mmap.len   = pos->end - pos->start;
		event->mmap.pid   = machine->pid;

		memcpy(event->mmap.filename, pos->dso->long_name,
		       pos->dso->long_name_len + 1);
		process(event, &synth_sample, session);
	}

	free(event);
	return 0;
}

static int __event__synthesize_thread(union perf_event *comm_event,
				      union perf_event *mmap_event,
				      pid_t pid, perf_event__handler_t process,
				      struct perf_session *session)
{
	pid_t tgid = perf_event__synthesize_comm(comm_event, pid, 1, process,
					    session);
	if (tgid == -1)
		return -1;
	return perf_event__synthesize_mmap_events(mmap_event, pid, tgid,
					     process, session);
}

int perf_event__synthesize_thread_map(struct thread_map *threads,
				      perf_event__handler_t process,
				      struct perf_session *session)
{
	union perf_event *comm_event, *mmap_event;
	int err = -1, thread;

	comm_event = malloc(sizeof(comm_event->comm) + session->id_hdr_size);
	if (comm_event == NULL)
		goto out;

	mmap_event = malloc(sizeof(mmap_event->mmap) + session->id_hdr_size);
	if (mmap_event == NULL)
		goto out_free_comm;

	err = 0;
	for (thread = 0; thread < threads->nr; ++thread) {
		if (__event__synthesize_thread(comm_event, mmap_event,
					       threads->map[thread],
					       process, session)) {
			err = -1;
			break;
		}
	}
	free(mmap_event);
out_free_comm:
	free(comm_event);
out:
	return err;
}

int perf_event__synthesize_threads(perf_event__handler_t process,
				   struct perf_session *session)
{
	DIR *proc;
	struct dirent dirent, *next;
	union perf_event *comm_event, *mmap_event;
	int err = -1;

	comm_event = malloc(sizeof(comm_event->comm) + session->id_hdr_size);
	if (comm_event == NULL)
		goto out;

	mmap_event = malloc(sizeof(mmap_event->mmap) + session->id_hdr_size);
	if (mmap_event == NULL)
		goto out_free_comm;

	proc = opendir("/proc");
	if (proc == NULL)
		goto out_free_mmap;

	while (!readdir_r(proc, &dirent, &next) && next) {
		char *end;
		pid_t pid = strtol(dirent.d_name, &end, 10);

		if (*end) /* only interested in proper numerical dirents */
			continue;

		__event__synthesize_thread(comm_event, mmap_event, pid,
					   process, session);
	}

	closedir(proc);
	err = 0;
out_free_mmap:
	free(mmap_event);
out_free_comm:
	free(comm_event);
out:
	return err;
}

struct process_symbol_args {
	const char *name;
	u64	   start;
};

static int find_symbol_cb(void *arg, const char *name, char type,
			  u64 start, u64 end __used)
{
	struct process_symbol_args *args = arg;

	/*
	 * Must be a function or at least an alias, as in PARISC64, where "_text" is
	 * an 'A' to the same address as "_stext".
	 */
	if (!(symbol_type__is_a(type, MAP__FUNCTION) ||
	      type == 'A') || strcmp(name, args->name))
		return 0;

	args->start = start;
	return 1;
}

int perf_event__synthesize_kernel_mmap(perf_event__handler_t process,
				       struct perf_session *session,
				       struct machine *machine,
				       const char *symbol_name)
{
	size_t size;
	const char *filename, *mmap_name;
	char path[PATH_MAX];
	char name_buff[PATH_MAX];
	struct map *map;
	int err;
	/*
	 * We should get this from /sys/kernel/sections/.text, but till that is
	 * available use this, and after it is use this as a fallback for older
	 * kernels.
	 */
	struct process_symbol_args args = { .name = symbol_name, };
	union perf_event *event = zalloc((sizeof(event->mmap) +
					  session->id_hdr_size));
	if (event == NULL) {
		pr_debug("Not enough memory synthesizing mmap event "
			 "for kernel modules\n");
		return -1;
	}

	mmap_name = machine__mmap_name(machine, name_buff, sizeof(name_buff));
	if (machine__is_host(machine)) {
		/*
		 * kernel uses PERF_RECORD_MISC_USER for user space maps,
		 * see kernel/perf_event.c __perf_event_mmap
		 */
		event->header.misc = PERF_RECORD_MISC_KERNEL;
		filename = "/proc/kallsyms";
	} else {
		event->header.misc = PERF_RECORD_MISC_GUEST_KERNEL;
		if (machine__is_default_guest(machine))
			filename = (char *) symbol_conf.default_guest_kallsyms;
		else {
			sprintf(path, "%s/proc/kallsyms", machine->root_dir);
			filename = path;
		}
	}

	if (kallsyms__parse(filename, &args, find_symbol_cb) <= 0)
		return -ENOENT;

	map = machine->vmlinux_maps[MAP__FUNCTION];
	size = snprintf(event->mmap.filename, sizeof(event->mmap.filename),
			"%s%s", mmap_name, symbol_name) + 1;
	size = ALIGN(size, sizeof(u64));
	event->mmap.header.type = PERF_RECORD_MMAP;
	event->mmap.header.size = (sizeof(event->mmap) -
			(sizeof(event->mmap.filename) - size) + session->id_hdr_size);
	event->mmap.pgoff = args.start;
	event->mmap.start = map->start;
	event->mmap.len   = map->end - event->mmap.start;
	event->mmap.pid   = machine->pid;

	err = process(event, &synth_sample, session);
	free(event);

	return err;
}

int perf_event__process_comm(union perf_event *event,
			     struct perf_sample *sample __used,
			     struct perf_session *session)
{
	struct thread *thread = perf_session__findnew(session, event->comm.tid);

	dump_printf(": %s:%d\n", event->comm.comm, event->comm.tid);

	if (thread == NULL || thread__set_comm(thread, event->comm.comm)) {
		dump_printf("problem processing PERF_RECORD_COMM, skipping event.\n");
		return -1;
	}

	return 0;
}

int perf_event__process_lost(union perf_event *event,
			     struct perf_sample *sample __used,
			     struct perf_session *session)
{
	dump_printf(": id:%" PRIu64 ": lost:%" PRIu64 "\n",
		    event->lost.id, event->lost.lost);
	session->hists.stats.total_lost += event->lost.lost;
	return 0;
}

static void perf_event__set_kernel_mmap_len(union perf_event *event,
					    struct map **maps)
{
	maps[MAP__FUNCTION]->start = event->mmap.start;
	maps[MAP__FUNCTION]->end   = event->mmap.start + event->mmap.len;
	/*
	 * Be a bit paranoid here, some perf.data file came with
	 * a zero sized synthesized MMAP event for the kernel.
	 */
	if (maps[MAP__FUNCTION]->end == 0)
		maps[MAP__FUNCTION]->end = ~0ULL;
}

static int perf_event__process_kernel_mmap(union perf_event *event,
					   struct perf_session *session)
{
	struct map *map;
	char kmmap_prefix[PATH_MAX];
	struct machine *machine;
	enum dso_kernel_type kernel_type;
	bool is_kernel_mmap;

	machine = perf_session__findnew_machine(session, event->mmap.pid);
	if (!machine) {
		pr_err("Can't find id %d's machine\n", event->mmap.pid);
		goto out_problem;
	}

	machine__mmap_name(machine, kmmap_prefix, sizeof(kmmap_prefix));
	if (machine__is_host(machine))
		kernel_type = DSO_TYPE_KERNEL;
	else
		kernel_type = DSO_TYPE_GUEST_KERNEL;

	is_kernel_mmap = memcmp(event->mmap.filename,
				kmmap_prefix,
				strlen(kmmap_prefix)) == 0;
	if (event->mmap.filename[0] == '/' ||
	    (!is_kernel_mmap && event->mmap.filename[0] == '[')) {

		char short_module_name[1024];
		char *name, *dot;

		if (event->mmap.filename[0] == '/') {
			name = strrchr(event->mmap.filename, '/');
			if (name == NULL)
				goto out_problem;

			++name; /* skip / */
			dot = strrchr(name, '.');
			if (dot == NULL)
				goto out_problem;
			snprintf(short_module_name, sizeof(short_module_name),
					"[%.*s]", (int)(dot - name), name);
			strxfrchar(short_module_name, '-', '_');
		} else
			strcpy(short_module_name, event->mmap.filename);

		map = machine__new_module(machine, event->mmap.start,
					  event->mmap.filename);
		if (map == NULL)
			goto out_problem;

		name = strdup(short_module_name);
		if (name == NULL)
			goto out_problem;

		map->dso->short_name = name;
		map->dso->sname_alloc = 1;
		map->end = map->start + event->mmap.len;
	} else if (is_kernel_mmap) {
		const char *symbol_name = (event->mmap.filename +
				strlen(kmmap_prefix));
		/*
		 * Should be there already, from the build-id table in
		 * the header.
		 */
		struct dso *kernel = __dsos__findnew(&machine->kernel_dsos,
						     kmmap_prefix);
		if (kernel == NULL)
			goto out_problem;

		kernel->kernel = kernel_type;
		if (__machine__create_kernel_maps(machine, kernel) < 0)
			goto out_problem;

		perf_event__set_kernel_mmap_len(event, machine->vmlinux_maps);
		perf_session__set_kallsyms_ref_reloc_sym(machine->vmlinux_maps,
							 symbol_name,
							 event->mmap.pgoff);
		if (machine__is_default_guest(machine)) {
			/*
			 * preload dso of guest kernel and modules
			 */
			dso__load(kernel, machine->vmlinux_maps[MAP__FUNCTION],
				  NULL);
		}
	}
	return 0;
out_problem:
	return -1;
}

int perf_event__process_mmap(union perf_event *event,
			     struct perf_sample *sample __used,
			     struct perf_session *session)
{
	struct machine *machine;
	struct thread *thread;
	struct map *map;
	u8 cpumode = event->header.misc & PERF_RECORD_MISC_CPUMODE_MASK;
	int ret = 0;

	dump_printf(" %d/%d: [%#" PRIx64 "(%#" PRIx64 ") @ %#" PRIx64 "]: %s\n",
			event->mmap.pid, event->mmap.tid, event->mmap.start,
			event->mmap.len, event->mmap.pgoff, event->mmap.filename);

	if (cpumode == PERF_RECORD_MISC_GUEST_KERNEL ||
	    cpumode == PERF_RECORD_MISC_KERNEL) {
		ret = perf_event__process_kernel_mmap(event, session);
		if (ret < 0)
			goto out_problem;
		return 0;
	}

	machine = perf_session__find_host_machine(session);
	if (machine == NULL)
		goto out_problem;
	thread = perf_session__findnew(session, event->mmap.pid);
	if (thread == NULL)
		goto out_problem;
	map = map__new(&machine->user_dsos, event->mmap.start,
			event->mmap.len, event->mmap.pgoff,
			event->mmap.pid, event->mmap.filename,
			MAP__FUNCTION);
	if (map == NULL)
		goto out_problem;

	thread__insert_map(thread, map);
	return 0;

out_problem:
	dump_printf("problem processing PERF_RECORD_MMAP, skipping event.\n");
	return 0;
}

int perf_event__process_task(union perf_event *event,
			     struct perf_sample *sample __used,
			     struct perf_session *session)
{
	struct thread *thread = perf_session__findnew(session, event->fork.tid);
	struct thread *parent = perf_session__findnew(session, event->fork.ptid);

	dump_printf("(%d:%d):(%d:%d)\n", event->fork.pid, event->fork.tid,
		    event->fork.ppid, event->fork.ptid);

	if (event->header.type == PERF_RECORD_EXIT) {
		perf_session__remove_thread(session, thread);
		return 0;
	}

	if (thread == NULL || parent == NULL ||
	    thread__fork(thread, parent) < 0) {
		dump_printf("problem processing PERF_RECORD_FORK, skipping event.\n");
		return -1;
	}

	return 0;
}

int perf_event__process(union perf_event *event, struct perf_sample *sample,
			struct perf_session *session)
{
	switch (event->header.type) {
	case PERF_RECORD_COMM:
		perf_event__process_comm(event, sample, session);
		break;
	case PERF_RECORD_MMAP:
		perf_event__process_mmap(event, sample, session);
		break;
	case PERF_RECORD_FORK:
	case PERF_RECORD_EXIT:
		perf_event__process_task(event, sample, session);
		break;
	case PERF_RECORD_LOST:
		perf_event__process_lost(event, sample, session);
	default:
		break;
	}

	return 0;
}

void thread__find_addr_map(struct thread *self,
			   struct perf_session *session, u8 cpumode,
			   enum map_type type, pid_t pid, u64 addr,
			   struct addr_location *al)
{
	struct map_groups *mg = &self->mg;
	struct machine *machine = NULL;

	al->thread = self;
	al->addr = addr;
	al->cpumode = cpumode;
	al->filtered = false;

	if (cpumode == PERF_RECORD_MISC_KERNEL && perf_host) {
		al->level = 'k';
		machine = perf_session__find_host_machine(session);
		if (machine == NULL) {
			al->map = NULL;
			return;
		}
		mg = &machine->kmaps;
	} else if (cpumode == PERF_RECORD_MISC_USER && perf_host) {
		al->level = '.';
		machine = perf_session__find_host_machine(session);
	} else if (cpumode == PERF_RECORD_MISC_GUEST_KERNEL && perf_guest) {
		al->level = 'g';
		machine = perf_session__find_machine(session, pid);
		if (machine == NULL) {
			al->map = NULL;
			return;
		}
		mg = &machine->kmaps;
	} else {
		/*
		 * 'u' means guest os user space.
		 * TODO: We don't support guest user space. Might support late.
		 */
		if (cpumode == PERF_RECORD_MISC_GUEST_USER && perf_guest)
			al->level = 'u';
		else
			al->level = 'H';
		al->map = NULL;

		if ((cpumode == PERF_RECORD_MISC_GUEST_USER ||
			cpumode == PERF_RECORD_MISC_GUEST_KERNEL) &&
			!perf_guest)
			al->filtered = true;
		if ((cpumode == PERF_RECORD_MISC_USER ||
			cpumode == PERF_RECORD_MISC_KERNEL) &&
			!perf_host)
			al->filtered = true;

		return;
	}
try_again:
	al->map = map_groups__find(mg, type, al->addr);
	if (al->map == NULL) {
		/*
		 * If this is outside of all known maps, and is a negative
		 * address, try to look it up in the kernel dso, as it might be
		 * a vsyscall or vdso (which executes in user-mode).
		 *
		 * XXX This is nasty, we should have a symbol list in the
		 * "[vdso]" dso, but for now lets use the old trick of looking
		 * in the whole kernel symbol list.
		 */
		if ((long long)al->addr < 0 &&
		    cpumode == PERF_RECORD_MISC_USER &&
		    machine && mg != &machine->kmaps) {
			mg = &machine->kmaps;
			goto try_again;
		}
	} else
		al->addr = al->map->map_ip(al->map, al->addr);
}

void thread__find_addr_location(struct thread *self,
				struct perf_session *session, u8 cpumode,
				enum map_type type, pid_t pid, u64 addr,
				struct addr_location *al,
				symbol_filter_t filter)
{
	thread__find_addr_map(self, session, cpumode, type, pid, addr, al);
	if (al->map != NULL)
		al->sym = map__find_symbol(al->map, al->addr, filter);
	else
		al->sym = NULL;
}

int perf_event__preprocess_sample(const union perf_event *event,
				  struct perf_session *session,
				  struct addr_location *al,
				  struct perf_sample *sample,
				  symbol_filter_t filter)
{
	u8 cpumode = event->header.misc & PERF_RECORD_MISC_CPUMODE_MASK;
	struct thread *thread = perf_session__findnew(session, event->ip.pid);

	if (thread == NULL)
		return -1;

	if (symbol_conf.comm_list &&
	    !strlist__has_entry(symbol_conf.comm_list, thread->comm))
		goto out_filtered;

	dump_printf(" ... thread: %s:%d\n", thread->comm, thread->pid);
	/*
	 * Have we already created the kernel maps for the host machine?
	 *
	 * This should have happened earlier, when we processed the kernel MMAP
	 * events, but for older perf.data files there was no such thing, so do
	 * it now.
	 */
	if (cpumode == PERF_RECORD_MISC_KERNEL &&
	    session->host_machine.vmlinux_maps[MAP__FUNCTION] == NULL)
		machine__create_kernel_maps(&session->host_machine);

	thread__find_addr_map(thread, session, cpumode, MAP__FUNCTION,
			      event->ip.pid, event->ip.ip, al);
	dump_printf(" ...... dso: %s\n",
		    al->map ? al->map->dso->long_name :
			al->level == 'H' ? "[hypervisor]" : "<not found>");
	al->sym = NULL;
	al->cpu = sample->cpu;

	if (al->map) {
		if (symbol_conf.dso_list &&
		    (!al->map || !al->map->dso ||
		     !(strlist__has_entry(symbol_conf.dso_list,
					  al->map->dso->short_name) ||
		       (al->map->dso->short_name != al->map->dso->long_name &&
			strlist__has_entry(symbol_conf.dso_list,
					   al->map->dso->long_name)))))
			goto out_filtered;

		al->sym = map__find_symbol(al->map, al->addr, filter);
	}

	if (symbol_conf.sym_list && al->sym &&
	    !strlist__has_entry(symbol_conf.sym_list, al->sym->name))
		goto out_filtered;

	return 0;

out_filtered:
	al->filtered = true;
	return 0;
}