xref: /linux/tools/perf/util/event.c (revision 12871a0bd67dd4db4418e1daafcd46e9d329ef10)
1 #include <linux/types.h>
2 #include "event.h"
3 #include "debug.h"
4 #include "session.h"
5 #include "sort.h"
6 #include "string.h"
7 #include "strlist.h"
8 #include "thread.h"
9 #include "thread_map.h"
10 
11 static const char *perf_event__names[] = {
12 	[0]					= "TOTAL",
13 	[PERF_RECORD_MMAP]			= "MMAP",
14 	[PERF_RECORD_LOST]			= "LOST",
15 	[PERF_RECORD_COMM]			= "COMM",
16 	[PERF_RECORD_EXIT]			= "EXIT",
17 	[PERF_RECORD_THROTTLE]			= "THROTTLE",
18 	[PERF_RECORD_UNTHROTTLE]		= "UNTHROTTLE",
19 	[PERF_RECORD_FORK]			= "FORK",
20 	[PERF_RECORD_READ]			= "READ",
21 	[PERF_RECORD_SAMPLE]			= "SAMPLE",
22 	[PERF_RECORD_HEADER_ATTR]		= "ATTR",
23 	[PERF_RECORD_HEADER_EVENT_TYPE]		= "EVENT_TYPE",
24 	[PERF_RECORD_HEADER_TRACING_DATA]	= "TRACING_DATA",
25 	[PERF_RECORD_HEADER_BUILD_ID]		= "BUILD_ID",
26 	[PERF_RECORD_FINISHED_ROUND]		= "FINISHED_ROUND",
27 };
28 
29 const char *perf_event__name(unsigned int id)
30 {
31 	if (id >= ARRAY_SIZE(perf_event__names))
32 		return "INVALID";
33 	if (!perf_event__names[id])
34 		return "UNKNOWN";
35 	return perf_event__names[id];
36 }
37 
38 int perf_sample_size(u64 sample_type)
39 {
40 	u64 mask = sample_type & PERF_SAMPLE_MASK;
41 	int size = 0;
42 	int i;
43 
44 	for (i = 0; i < 64; i++) {
45 		if (mask & (1ULL << i))
46 			size++;
47 	}
48 
49 	size *= sizeof(u64);
50 
51 	return size;
52 }
53 
54 static struct perf_sample synth_sample = {
55 	.pid	   = -1,
56 	.tid	   = -1,
57 	.time	   = -1,
58 	.stream_id = -1,
59 	.cpu	   = -1,
60 	.period	   = 1,
61 };
62 
63 static pid_t perf_event__synthesize_comm(union perf_event *event, pid_t pid,
64 					 int full, perf_event__handler_t process,
65 					 struct perf_session *session)
66 {
67 	char filename[PATH_MAX];
68 	char bf[BUFSIZ];
69 	FILE *fp;
70 	size_t size = 0;
71 	DIR *tasks;
72 	struct dirent dirent, *next;
73 	pid_t tgid = 0;
74 
75 	snprintf(filename, sizeof(filename), "/proc/%d/status", pid);
76 
77 	fp = fopen(filename, "r");
78 	if (fp == NULL) {
79 out_race:
80 		/*
81 		 * We raced with a task exiting - just return:
82 		 */
83 		pr_debug("couldn't open %s\n", filename);
84 		return 0;
85 	}
86 
87 	memset(&event->comm, 0, sizeof(event->comm));
88 
89 	while (!event->comm.comm[0] || !event->comm.pid) {
90 		if (fgets(bf, sizeof(bf), fp) == NULL) {
91 			pr_warning("couldn't get COMM and pgid, malformed %s\n", filename);
92 			goto out;
93 		}
94 
95 		if (memcmp(bf, "Name:", 5) == 0) {
96 			char *name = bf + 5;
97 			while (*name && isspace(*name))
98 				++name;
99 			size = strlen(name) - 1;
100 			memcpy(event->comm.comm, name, size++);
101 		} else if (memcmp(bf, "Tgid:", 5) == 0) {
102 			char *tgids = bf + 5;
103 			while (*tgids && isspace(*tgids))
104 				++tgids;
105 			tgid = event->comm.pid = atoi(tgids);
106 		}
107 	}
108 
109 	event->comm.header.type = PERF_RECORD_COMM;
110 	size = ALIGN(size, sizeof(u64));
111 	memset(event->comm.comm + size, 0, session->id_hdr_size);
112 	event->comm.header.size = (sizeof(event->comm) -
113 				(sizeof(event->comm.comm) - size) +
114 				session->id_hdr_size);
115 	if (!full) {
116 		event->comm.tid = pid;
117 
118 		process(event, &synth_sample, session);
119 		goto out;
120 	}
121 
122 	snprintf(filename, sizeof(filename), "/proc/%d/task", pid);
123 
124 	tasks = opendir(filename);
125 	if (tasks == NULL)
126 		goto out_race;
127 
128 	while (!readdir_r(tasks, &dirent, &next) && next) {
129 		char *end;
130 		pid = strtol(dirent.d_name, &end, 10);
131 		if (*end)
132 			continue;
133 
134 		event->comm.tid = pid;
135 
136 		process(event, &synth_sample, session);
137 	}
138 
139 	closedir(tasks);
140 out:
141 	fclose(fp);
142 
143 	return tgid;
144 }
145 
146 static int perf_event__synthesize_mmap_events(union perf_event *event,
147 					      pid_t pid, pid_t tgid,
148 					      perf_event__handler_t process,
149 					      struct perf_session *session)
150 {
151 	char filename[PATH_MAX];
152 	FILE *fp;
153 
154 	snprintf(filename, sizeof(filename), "/proc/%d/maps", pid);
155 
156 	fp = fopen(filename, "r");
157 	if (fp == NULL) {
158 		/*
159 		 * We raced with a task exiting - just return:
160 		 */
161 		pr_debug("couldn't open %s\n", filename);
162 		return -1;
163 	}
164 
165 	event->header.type = PERF_RECORD_MMAP;
166 	/*
167 	 * Just like the kernel, see __perf_event_mmap in kernel/perf_event.c
168 	 */
169 	event->header.misc = PERF_RECORD_MISC_USER;
170 
171 	while (1) {
172 		char bf[BUFSIZ], *pbf = bf;
173 		int n;
174 		size_t size;
175 		if (fgets(bf, sizeof(bf), fp) == NULL)
176 			break;
177 
178 		/* 00400000-0040c000 r-xp 00000000 fd:01 41038  /bin/cat */
179 		n = hex2u64(pbf, &event->mmap.start);
180 		if (n < 0)
181 			continue;
182 		pbf += n + 1;
183 		n = hex2u64(pbf, &event->mmap.len);
184 		if (n < 0)
185 			continue;
186 		pbf += n + 3;
187 		if (*pbf == 'x') { /* vm_exec */
188 			char *execname = strchr(bf, '/');
189 
190 			/* Catch VDSO */
191 			if (execname == NULL)
192 				execname = strstr(bf, "[vdso]");
193 
194 			if (execname == NULL)
195 				continue;
196 
197 			pbf += 3;
198 			n = hex2u64(pbf, &event->mmap.pgoff);
199 
200 			size = strlen(execname);
201 			execname[size - 1] = '\0'; /* Remove \n */
202 			memcpy(event->mmap.filename, execname, size);
203 			size = ALIGN(size, sizeof(u64));
204 			event->mmap.len -= event->mmap.start;
205 			event->mmap.header.size = (sizeof(event->mmap) -
206 					        (sizeof(event->mmap.filename) - size));
207 			memset(event->mmap.filename + size, 0, session->id_hdr_size);
208 			event->mmap.header.size += session->id_hdr_size;
209 			event->mmap.pid = tgid;
210 			event->mmap.tid = pid;
211 
212 			process(event, &synth_sample, session);
213 		}
214 	}
215 
216 	fclose(fp);
217 	return 0;
218 }
219 
220 int perf_event__synthesize_modules(perf_event__handler_t process,
221 				   struct perf_session *session,
222 				   struct machine *machine)
223 {
224 	struct rb_node *nd;
225 	struct map_groups *kmaps = &machine->kmaps;
226 	union perf_event *event = zalloc((sizeof(event->mmap) +
227 					  session->id_hdr_size));
228 	if (event == NULL) {
229 		pr_debug("Not enough memory synthesizing mmap event "
230 			 "for kernel modules\n");
231 		return -1;
232 	}
233 
234 	event->header.type = PERF_RECORD_MMAP;
235 
236 	/*
237 	 * kernel uses 0 for user space maps, see kernel/perf_event.c
238 	 * __perf_event_mmap
239 	 */
240 	if (machine__is_host(machine))
241 		event->header.misc = PERF_RECORD_MISC_KERNEL;
242 	else
243 		event->header.misc = PERF_RECORD_MISC_GUEST_KERNEL;
244 
245 	for (nd = rb_first(&kmaps->maps[MAP__FUNCTION]);
246 	     nd; nd = rb_next(nd)) {
247 		size_t size;
248 		struct map *pos = rb_entry(nd, struct map, rb_node);
249 
250 		if (pos->dso->kernel)
251 			continue;
252 
253 		size = ALIGN(pos->dso->long_name_len + 1, sizeof(u64));
254 		event->mmap.header.type = PERF_RECORD_MMAP;
255 		event->mmap.header.size = (sizeof(event->mmap) -
256 				        (sizeof(event->mmap.filename) - size));
257 		memset(event->mmap.filename + size, 0, session->id_hdr_size);
258 		event->mmap.header.size += session->id_hdr_size;
259 		event->mmap.start = pos->start;
260 		event->mmap.len   = pos->end - pos->start;
261 		event->mmap.pid   = machine->pid;
262 
263 		memcpy(event->mmap.filename, pos->dso->long_name,
264 		       pos->dso->long_name_len + 1);
265 		process(event, &synth_sample, session);
266 	}
267 
268 	free(event);
269 	return 0;
270 }
271 
272 static int __event__synthesize_thread(union perf_event *comm_event,
273 				      union perf_event *mmap_event,
274 				      pid_t pid, perf_event__handler_t process,
275 				      struct perf_session *session)
276 {
277 	pid_t tgid = perf_event__synthesize_comm(comm_event, pid, 1, process,
278 					    session);
279 	if (tgid == -1)
280 		return -1;
281 	return perf_event__synthesize_mmap_events(mmap_event, pid, tgid,
282 					     process, session);
283 }
284 
285 int perf_event__synthesize_thread_map(struct thread_map *threads,
286 				      perf_event__handler_t process,
287 				      struct perf_session *session)
288 {
289 	union perf_event *comm_event, *mmap_event;
290 	int err = -1, thread;
291 
292 	comm_event = malloc(sizeof(comm_event->comm) + session->id_hdr_size);
293 	if (comm_event == NULL)
294 		goto out;
295 
296 	mmap_event = malloc(sizeof(mmap_event->mmap) + session->id_hdr_size);
297 	if (mmap_event == NULL)
298 		goto out_free_comm;
299 
300 	err = 0;
301 	for (thread = 0; thread < threads->nr; ++thread) {
302 		if (__event__synthesize_thread(comm_event, mmap_event,
303 					       threads->map[thread],
304 					       process, session)) {
305 			err = -1;
306 			break;
307 		}
308 	}
309 	free(mmap_event);
310 out_free_comm:
311 	free(comm_event);
312 out:
313 	return err;
314 }
315 
316 int perf_event__synthesize_threads(perf_event__handler_t process,
317 				   struct perf_session *session)
318 {
319 	DIR *proc;
320 	struct dirent dirent, *next;
321 	union perf_event *comm_event, *mmap_event;
322 	int err = -1;
323 
324 	comm_event = malloc(sizeof(comm_event->comm) + session->id_hdr_size);
325 	if (comm_event == NULL)
326 		goto out;
327 
328 	mmap_event = malloc(sizeof(mmap_event->mmap) + session->id_hdr_size);
329 	if (mmap_event == NULL)
330 		goto out_free_comm;
331 
332 	proc = opendir("/proc");
333 	if (proc == NULL)
334 		goto out_free_mmap;
335 
336 	while (!readdir_r(proc, &dirent, &next) && next) {
337 		char *end;
338 		pid_t pid = strtol(dirent.d_name, &end, 10);
339 
340 		if (*end) /* only interested in proper numerical dirents */
341 			continue;
342 
343 		__event__synthesize_thread(comm_event, mmap_event, pid,
344 					   process, session);
345 	}
346 
347 	closedir(proc);
348 	err = 0;
349 out_free_mmap:
350 	free(mmap_event);
351 out_free_comm:
352 	free(comm_event);
353 out:
354 	return err;
355 }
356 
357 struct process_symbol_args {
358 	const char *name;
359 	u64	   start;
360 };
361 
362 static int find_symbol_cb(void *arg, const char *name, char type,
363 			  u64 start, u64 end __used)
364 {
365 	struct process_symbol_args *args = arg;
366 
367 	/*
368 	 * Must be a function or at least an alias, as in PARISC64, where "_text" is
369 	 * an 'A' to the same address as "_stext".
370 	 */
371 	if (!(symbol_type__is_a(type, MAP__FUNCTION) ||
372 	      type == 'A') || strcmp(name, args->name))
373 		return 0;
374 
375 	args->start = start;
376 	return 1;
377 }
378 
379 int perf_event__synthesize_kernel_mmap(perf_event__handler_t process,
380 				       struct perf_session *session,
381 				       struct machine *machine,
382 				       const char *symbol_name)
383 {
384 	size_t size;
385 	const char *filename, *mmap_name;
386 	char path[PATH_MAX];
387 	char name_buff[PATH_MAX];
388 	struct map *map;
389 	int err;
390 	/*
391 	 * We should get this from /sys/kernel/sections/.text, but till that is
392 	 * available use this, and after it is use this as a fallback for older
393 	 * kernels.
394 	 */
395 	struct process_symbol_args args = { .name = symbol_name, };
396 	union perf_event *event = zalloc((sizeof(event->mmap) +
397 					  session->id_hdr_size));
398 	if (event == NULL) {
399 		pr_debug("Not enough memory synthesizing mmap event "
400 			 "for kernel modules\n");
401 		return -1;
402 	}
403 
404 	mmap_name = machine__mmap_name(machine, name_buff, sizeof(name_buff));
405 	if (machine__is_host(machine)) {
406 		/*
407 		 * kernel uses PERF_RECORD_MISC_USER for user space maps,
408 		 * see kernel/perf_event.c __perf_event_mmap
409 		 */
410 		event->header.misc = PERF_RECORD_MISC_KERNEL;
411 		filename = "/proc/kallsyms";
412 	} else {
413 		event->header.misc = PERF_RECORD_MISC_GUEST_KERNEL;
414 		if (machine__is_default_guest(machine))
415 			filename = (char *) symbol_conf.default_guest_kallsyms;
416 		else {
417 			sprintf(path, "%s/proc/kallsyms", machine->root_dir);
418 			filename = path;
419 		}
420 	}
421 
422 	if (kallsyms__parse(filename, &args, find_symbol_cb) <= 0)
423 		return -ENOENT;
424 
425 	map = machine->vmlinux_maps[MAP__FUNCTION];
426 	size = snprintf(event->mmap.filename, sizeof(event->mmap.filename),
427 			"%s%s", mmap_name, symbol_name) + 1;
428 	size = ALIGN(size, sizeof(u64));
429 	event->mmap.header.type = PERF_RECORD_MMAP;
430 	event->mmap.header.size = (sizeof(event->mmap) -
431 			(sizeof(event->mmap.filename) - size) + session->id_hdr_size);
432 	event->mmap.pgoff = args.start;
433 	event->mmap.start = map->start;
434 	event->mmap.len   = map->end - event->mmap.start;
435 	event->mmap.pid   = machine->pid;
436 
437 	err = process(event, &synth_sample, session);
438 	free(event);
439 
440 	return err;
441 }
442 
443 int perf_event__process_comm(union perf_event *event,
444 			     struct perf_sample *sample __used,
445 			     struct perf_session *session)
446 {
447 	struct thread *thread = perf_session__findnew(session, event->comm.tid);
448 
449 	dump_printf(": %s:%d\n", event->comm.comm, event->comm.tid);
450 
451 	if (thread == NULL || thread__set_comm(thread, event->comm.comm)) {
452 		dump_printf("problem processing PERF_RECORD_COMM, skipping event.\n");
453 		return -1;
454 	}
455 
456 	return 0;
457 }
458 
459 int perf_event__process_lost(union perf_event *event,
460 			     struct perf_sample *sample __used,
461 			     struct perf_session *session)
462 {
463 	dump_printf(": id:%" PRIu64 ": lost:%" PRIu64 "\n",
464 		    event->lost.id, event->lost.lost);
465 	session->hists.stats.total_lost += event->lost.lost;
466 	return 0;
467 }
468 
469 static void perf_event__set_kernel_mmap_len(union perf_event *event,
470 					    struct map **maps)
471 {
472 	maps[MAP__FUNCTION]->start = event->mmap.start;
473 	maps[MAP__FUNCTION]->end   = event->mmap.start + event->mmap.len;
474 	/*
475 	 * Be a bit paranoid here, some perf.data file came with
476 	 * a zero sized synthesized MMAP event for the kernel.
477 	 */
478 	if (maps[MAP__FUNCTION]->end == 0)
479 		maps[MAP__FUNCTION]->end = ~0ULL;
480 }
481 
482 static int perf_event__process_kernel_mmap(union perf_event *event,
483 					   struct perf_session *session)
484 {
485 	struct map *map;
486 	char kmmap_prefix[PATH_MAX];
487 	struct machine *machine;
488 	enum dso_kernel_type kernel_type;
489 	bool is_kernel_mmap;
490 
491 	machine = perf_session__findnew_machine(session, event->mmap.pid);
492 	if (!machine) {
493 		pr_err("Can't find id %d's machine\n", event->mmap.pid);
494 		goto out_problem;
495 	}
496 
497 	machine__mmap_name(machine, kmmap_prefix, sizeof(kmmap_prefix));
498 	if (machine__is_host(machine))
499 		kernel_type = DSO_TYPE_KERNEL;
500 	else
501 		kernel_type = DSO_TYPE_GUEST_KERNEL;
502 
503 	is_kernel_mmap = memcmp(event->mmap.filename,
504 				kmmap_prefix,
505 				strlen(kmmap_prefix)) == 0;
506 	if (event->mmap.filename[0] == '/' ||
507 	    (!is_kernel_mmap && event->mmap.filename[0] == '[')) {
508 
509 		char short_module_name[1024];
510 		char *name, *dot;
511 
512 		if (event->mmap.filename[0] == '/') {
513 			name = strrchr(event->mmap.filename, '/');
514 			if (name == NULL)
515 				goto out_problem;
516 
517 			++name; /* skip / */
518 			dot = strrchr(name, '.');
519 			if (dot == NULL)
520 				goto out_problem;
521 			snprintf(short_module_name, sizeof(short_module_name),
522 					"[%.*s]", (int)(dot - name), name);
523 			strxfrchar(short_module_name, '-', '_');
524 		} else
525 			strcpy(short_module_name, event->mmap.filename);
526 
527 		map = machine__new_module(machine, event->mmap.start,
528 					  event->mmap.filename);
529 		if (map == NULL)
530 			goto out_problem;
531 
532 		name = strdup(short_module_name);
533 		if (name == NULL)
534 			goto out_problem;
535 
536 		map->dso->short_name = name;
537 		map->dso->sname_alloc = 1;
538 		map->end = map->start + event->mmap.len;
539 	} else if (is_kernel_mmap) {
540 		const char *symbol_name = (event->mmap.filename +
541 				strlen(kmmap_prefix));
542 		/*
543 		 * Should be there already, from the build-id table in
544 		 * the header.
545 		 */
546 		struct dso *kernel = __dsos__findnew(&machine->kernel_dsos,
547 						     kmmap_prefix);
548 		if (kernel == NULL)
549 			goto out_problem;
550 
551 		kernel->kernel = kernel_type;
552 		if (__machine__create_kernel_maps(machine, kernel) < 0)
553 			goto out_problem;
554 
555 		perf_event__set_kernel_mmap_len(event, machine->vmlinux_maps);
556 
557 		/*
558 		 * Avoid using a zero address (kptr_restrict) for the ref reloc
559 		 * symbol. Effectively having zero here means that at record
560 		 * time /proc/sys/kernel/kptr_restrict was non zero.
561 		 */
562 		if (event->mmap.pgoff != 0) {
563 			perf_session__set_kallsyms_ref_reloc_sym(machine->vmlinux_maps,
564 								 symbol_name,
565 								 event->mmap.pgoff);
566 		}
567 
568 		if (machine__is_default_guest(machine)) {
569 			/*
570 			 * preload dso of guest kernel and modules
571 			 */
572 			dso__load(kernel, machine->vmlinux_maps[MAP__FUNCTION],
573 				  NULL);
574 		}
575 	}
576 	return 0;
577 out_problem:
578 	return -1;
579 }
580 
581 int perf_event__process_mmap(union perf_event *event,
582 			     struct perf_sample *sample __used,
583 			     struct perf_session *session)
584 {
585 	struct machine *machine;
586 	struct thread *thread;
587 	struct map *map;
588 	u8 cpumode = event->header.misc & PERF_RECORD_MISC_CPUMODE_MASK;
589 	int ret = 0;
590 
591 	dump_printf(" %d/%d: [%#" PRIx64 "(%#" PRIx64 ") @ %#" PRIx64 "]: %s\n",
592 			event->mmap.pid, event->mmap.tid, event->mmap.start,
593 			event->mmap.len, event->mmap.pgoff, event->mmap.filename);
594 
595 	if (cpumode == PERF_RECORD_MISC_GUEST_KERNEL ||
596 	    cpumode == PERF_RECORD_MISC_KERNEL) {
597 		ret = perf_event__process_kernel_mmap(event, session);
598 		if (ret < 0)
599 			goto out_problem;
600 		return 0;
601 	}
602 
603 	machine = perf_session__find_host_machine(session);
604 	if (machine == NULL)
605 		goto out_problem;
606 	thread = perf_session__findnew(session, event->mmap.pid);
607 	if (thread == NULL)
608 		goto out_problem;
609 	map = map__new(&machine->user_dsos, event->mmap.start,
610 			event->mmap.len, event->mmap.pgoff,
611 			event->mmap.pid, event->mmap.filename,
612 			MAP__FUNCTION);
613 	if (map == NULL)
614 		goto out_problem;
615 
616 	thread__insert_map(thread, map);
617 	return 0;
618 
619 out_problem:
620 	dump_printf("problem processing PERF_RECORD_MMAP, skipping event.\n");
621 	return 0;
622 }
623 
624 int perf_event__process_task(union perf_event *event,
625 			     struct perf_sample *sample __used,
626 			     struct perf_session *session)
627 {
628 	struct thread *thread = perf_session__findnew(session, event->fork.tid);
629 	struct thread *parent = perf_session__findnew(session, event->fork.ptid);
630 
631 	dump_printf("(%d:%d):(%d:%d)\n", event->fork.pid, event->fork.tid,
632 		    event->fork.ppid, event->fork.ptid);
633 
634 	if (event->header.type == PERF_RECORD_EXIT) {
635 		perf_session__remove_thread(session, thread);
636 		return 0;
637 	}
638 
639 	if (thread == NULL || parent == NULL ||
640 	    thread__fork(thread, parent) < 0) {
641 		dump_printf("problem processing PERF_RECORD_FORK, skipping event.\n");
642 		return -1;
643 	}
644 
645 	return 0;
646 }
647 
648 int perf_event__process(union perf_event *event, struct perf_sample *sample,
649 			struct perf_session *session)
650 {
651 	switch (event->header.type) {
652 	case PERF_RECORD_COMM:
653 		perf_event__process_comm(event, sample, session);
654 		break;
655 	case PERF_RECORD_MMAP:
656 		perf_event__process_mmap(event, sample, session);
657 		break;
658 	case PERF_RECORD_FORK:
659 	case PERF_RECORD_EXIT:
660 		perf_event__process_task(event, sample, session);
661 		break;
662 	case PERF_RECORD_LOST:
663 		perf_event__process_lost(event, sample, session);
664 	default:
665 		break;
666 	}
667 
668 	return 0;
669 }
670 
671 void thread__find_addr_map(struct thread *self,
672 			   struct perf_session *session, u8 cpumode,
673 			   enum map_type type, pid_t pid, u64 addr,
674 			   struct addr_location *al)
675 {
676 	struct map_groups *mg = &self->mg;
677 	struct machine *machine = NULL;
678 
679 	al->thread = self;
680 	al->addr = addr;
681 	al->cpumode = cpumode;
682 	al->filtered = false;
683 
684 	if (cpumode == PERF_RECORD_MISC_KERNEL && perf_host) {
685 		al->level = 'k';
686 		machine = perf_session__find_host_machine(session);
687 		if (machine == NULL) {
688 			al->map = NULL;
689 			return;
690 		}
691 		mg = &machine->kmaps;
692 	} else if (cpumode == PERF_RECORD_MISC_USER && perf_host) {
693 		al->level = '.';
694 		machine = perf_session__find_host_machine(session);
695 	} else if (cpumode == PERF_RECORD_MISC_GUEST_KERNEL && perf_guest) {
696 		al->level = 'g';
697 		machine = perf_session__find_machine(session, pid);
698 		if (machine == NULL) {
699 			al->map = NULL;
700 			return;
701 		}
702 		mg = &machine->kmaps;
703 	} else {
704 		/*
705 		 * 'u' means guest os user space.
706 		 * TODO: We don't support guest user space. Might support late.
707 		 */
708 		if (cpumode == PERF_RECORD_MISC_GUEST_USER && perf_guest)
709 			al->level = 'u';
710 		else
711 			al->level = 'H';
712 		al->map = NULL;
713 
714 		if ((cpumode == PERF_RECORD_MISC_GUEST_USER ||
715 			cpumode == PERF_RECORD_MISC_GUEST_KERNEL) &&
716 			!perf_guest)
717 			al->filtered = true;
718 		if ((cpumode == PERF_RECORD_MISC_USER ||
719 			cpumode == PERF_RECORD_MISC_KERNEL) &&
720 			!perf_host)
721 			al->filtered = true;
722 
723 		return;
724 	}
725 try_again:
726 	al->map = map_groups__find(mg, type, al->addr);
727 	if (al->map == NULL) {
728 		/*
729 		 * If this is outside of all known maps, and is a negative
730 		 * address, try to look it up in the kernel dso, as it might be
731 		 * a vsyscall or vdso (which executes in user-mode).
732 		 *
733 		 * XXX This is nasty, we should have a symbol list in the
734 		 * "[vdso]" dso, but for now lets use the old trick of looking
735 		 * in the whole kernel symbol list.
736 		 */
737 		if ((long long)al->addr < 0 &&
738 		    cpumode == PERF_RECORD_MISC_USER &&
739 		    machine && mg != &machine->kmaps) {
740 			mg = &machine->kmaps;
741 			goto try_again;
742 		}
743 	} else
744 		al->addr = al->map->map_ip(al->map, al->addr);
745 }
746 
747 void thread__find_addr_location(struct thread *self,
748 				struct perf_session *session, u8 cpumode,
749 				enum map_type type, pid_t pid, u64 addr,
750 				struct addr_location *al,
751 				symbol_filter_t filter)
752 {
753 	thread__find_addr_map(self, session, cpumode, type, pid, addr, al);
754 	if (al->map != NULL)
755 		al->sym = map__find_symbol(al->map, al->addr, filter);
756 	else
757 		al->sym = NULL;
758 }
759 
760 int perf_event__preprocess_sample(const union perf_event *event,
761 				  struct perf_session *session,
762 				  struct addr_location *al,
763 				  struct perf_sample *sample,
764 				  symbol_filter_t filter)
765 {
766 	u8 cpumode = event->header.misc & PERF_RECORD_MISC_CPUMODE_MASK;
767 	struct thread *thread = perf_session__findnew(session, event->ip.pid);
768 
769 	if (thread == NULL)
770 		return -1;
771 
772 	if (symbol_conf.comm_list &&
773 	    !strlist__has_entry(symbol_conf.comm_list, thread->comm))
774 		goto out_filtered;
775 
776 	dump_printf(" ... thread: %s:%d\n", thread->comm, thread->pid);
777 	/*
778 	 * Have we already created the kernel maps for the host machine?
779 	 *
780 	 * This should have happened earlier, when we processed the kernel MMAP
781 	 * events, but for older perf.data files there was no such thing, so do
782 	 * it now.
783 	 */
784 	if (cpumode == PERF_RECORD_MISC_KERNEL &&
785 	    session->host_machine.vmlinux_maps[MAP__FUNCTION] == NULL)
786 		machine__create_kernel_maps(&session->host_machine);
787 
788 	thread__find_addr_map(thread, session, cpumode, MAP__FUNCTION,
789 			      event->ip.pid, event->ip.ip, al);
790 	dump_printf(" ...... dso: %s\n",
791 		    al->map ? al->map->dso->long_name :
792 			al->level == 'H' ? "[hypervisor]" : "<not found>");
793 	al->sym = NULL;
794 	al->cpu = sample->cpu;
795 
796 	if (al->map) {
797 		if (symbol_conf.dso_list &&
798 		    (!al->map || !al->map->dso ||
799 		     !(strlist__has_entry(symbol_conf.dso_list,
800 					  al->map->dso->short_name) ||
801 		       (al->map->dso->short_name != al->map->dso->long_name &&
802 			strlist__has_entry(symbol_conf.dso_list,
803 					   al->map->dso->long_name)))))
804 			goto out_filtered;
805 
806 		al->sym = map__find_symbol(al->map, al->addr, filter);
807 	}
808 
809 	if (symbol_conf.sym_list && al->sym &&
810 	    !strlist__has_entry(symbol_conf.sym_list, al->sym->name))
811 		goto out_filtered;
812 
813 	return 0;
814 
815 out_filtered:
816 	al->filtered = true;
817 	return 0;
818 }
819