summaryrefslogtreecommitdiffstats
path: root/tools/perf/util/event.c
blob: 7ff61274ed57f5219416c69767fac9acca21e091 (plain)
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
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
870
871
872
873
874
875
876
877
878
879
880
881
882
883
884
885
886
887
888
889
890
891
892
893
894
895
896
897
898
899
900
901
902
903
904
905
906
907
908
909
910
911
912
913
914
915
916
917
918
919
920
921
922
923
924
925
926
927
928
929
930
931
932
933
934
935
936
937
938
939
940
941
942
943
944
945
946
947
948
949
950
951
952
953
954
955
956
957
958
959
960
961
962
963
964
965
966
967
968
969
970
971
972
973
974
975
976
977
978
979
980
981
982
983
984
985
986
987
988
989
990
991
992
993
994
995
996
997
998
999
1000
1001
1002
1003
1004
1005
1006
1007
1008
1009
1010
1011
1012
1013
1014
1015
1016
1017
1018
1019
1020
1021
1022
1023
1024
1025
1026
1027
1028
1029
1030
1031
1032
1033
1034
1035
1036
1037
1038
1039
1040
1041
1042
1043
1044
1045
1046
1047
1048
1049
1050
1051
1052
1053
1054
1055
1056
1057
1058
1059
1060
1061
1062
1063
1064
1065
1066
1067
1068
1069
1070
1071
1072
1073
1074
1075
1076
1077
1078
1079
1080
1081
1082
1083
1084
1085
1086
1087
1088
1089
1090
1091
1092
1093
1094
1095
1096
1097
1098
1099
#include <linux/types.h>
#include <sys/mman.h>
#include "event.h"
#include "debug.h"
#include "hist.h"
#include "machine.h"
#include "sort.h"
#include "string.h"
#include "strlist.h"
#include "thread.h"
#include "thread_map.h"
#include "symbol/kallsyms.h"

static const char *perf_event__names[] = {
	[0]					= "TOTAL",
	[PERF_RECORD_MMAP]			= "MMAP",
	[PERF_RECORD_MMAP2]			= "MMAP2",
	[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_AUX]			= "AUX",
	[PERF_RECORD_ITRACE_START]		= "ITRACE_START",
	[PERF_RECORD_LOST_SAMPLES]		= "LOST_SAMPLES",
	[PERF_RECORD_SWITCH]			= "SWITCH",
	[PERF_RECORD_SWITCH_CPU_WIDE]		= "SWITCH_CPU_WIDE",
	[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",
	[PERF_RECORD_ID_INDEX]			= "ID_INDEX",
	[PERF_RECORD_AUXTRACE_INFO]		= "AUXTRACE_INFO",
	[PERF_RECORD_AUXTRACE]			= "AUXTRACE",
	[PERF_RECORD_AUXTRACE_ERROR]		= "AUXTRACE_ERROR",
};

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];
}

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

/*
 * Assumes that the first 4095 bytes of /proc/pid/stat contains
 * the comm, tgid and ppid.
 */
static int perf_event__get_comm_ids(pid_t pid, char *comm, size_t len,
				    pid_t *tgid, pid_t *ppid)
{
	char filename[PATH_MAX];
	char bf[4096];
	int fd;
	size_t size = 0, n;
	char *nl, *name, *tgids, *ppids;

	*tgid = -1;
	*ppid = -1;

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

	fd = open(filename, O_RDONLY);
	if (fd < 0) {
		pr_debug("couldn't open %s\n", filename);
		return -1;
	}

	n = read(fd, bf, sizeof(bf) - 1);
	close(fd);
	if (n <= 0) {
		pr_warning("Couldn't get COMM, tigd and ppid for pid %d\n",
			   pid);
		return -1;
	}
	bf[n] = '\0';

	name = strstr(bf, "Name:");
	tgids = strstr(bf, "Tgid:");
	ppids = strstr(bf, "PPid:");

	if (name) {
		name += 5;  /* strlen("Name:") */

		while (*name && isspace(*name))
			++name;

		nl = strchr(name, '\n');
		if (nl)
			*nl = '\0';

		size = strlen(name);
		if (size >= len)
			size = len - 1;
		memcpy(comm, name, size);
		comm[size] = '\0';
	} else {
		pr_debug("Name: string not found for pid %d\n", pid);
	}

	if (tgids) {
		tgids += 5;  /* strlen("Tgid:") */
		*tgid = atoi(tgids);
	} else {
		pr_debug("Tgid: string not found for pid %d\n", pid);
	}

	if (ppids) {
		ppids += 5;  /* strlen("PPid:") */
		*ppid = atoi(ppids);
	} else {
		pr_debug("PPid: string not found for pid %d\n", pid);
	}

	return 0;
}

static int perf_event__prepare_comm(union perf_event *event, pid_t pid,
				    struct machine *machine,
				    pid_t *tgid, pid_t *ppid)
{
	size_t size;

	*ppid = -1;

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

	if (machine__is_host(machine)) {
		if (perf_event__get_comm_ids(pid, event->comm.comm,
					     sizeof(event->comm.comm),
					     tgid, ppid) != 0) {
			return -1;
		}
	} else {
		*tgid = machine->pid;
	}

	if (*tgid < 0)
		return -1;

	event->comm.pid = *tgid;
	event->comm.header.type = PERF_RECORD_COMM;

	size = strlen(event->comm.comm) + 1;
	size = PERF_ALIGN(size, sizeof(u64));
	memset(event->comm.comm + size, 0, machine->id_hdr_size);
	event->comm.header.size = (sizeof(event->comm) -
				(sizeof(event->comm.comm) - size) +
				machine->id_hdr_size);
	event->comm.tid = pid;

	return 0;
}

static pid_t perf_event__synthesize_comm(struct perf_tool *tool,
					 union perf_event *event, pid_t pid,
					 perf_event__handler_t process,
					 struct machine *machine)
{
	pid_t tgid, ppid;

	if (perf_event__prepare_comm(event, pid, machine, &tgid, &ppid) != 0)
		return -1;

	if (process(tool, event, &synth_sample, machine) != 0)
		return -1;

	return tgid;
}

static int perf_event__synthesize_fork(struct perf_tool *tool,
				       union perf_event *event,
				       pid_t pid, pid_t tgid, pid_t ppid,
				       perf_event__handler_t process,
				       struct machine *machine)
{
	memset(&event->fork, 0, sizeof(event->fork) + machine->id_hdr_size);

	/*
	 * for main thread set parent to ppid from status file. For other
	 * threads set parent pid to main thread. ie., assume main thread
	 * spawns all threads in a process
	*/
	if (tgid == pid) {
		event->fork.ppid = ppid;
		event->fork.ptid = ppid;
	} else {
		event->fork.ppid = tgid;
		event->fork.ptid = tgid;
	}
	event->fork.pid  = tgid;
	event->fork.tid  = pid;
	event->fork.header.type = PERF_RECORD_FORK;

	event->fork.header.size = (sizeof(event->fork) + machine->id_hdr_size);

	if (process(tool, event, &synth_sample, machine) != 0)
		return -1;

	return 0;
}

int perf_event__synthesize_mmap_events(struct perf_tool *tool,
				       union perf_event *event,
				       pid_t pid, pid_t tgid,
				       perf_event__handler_t process,
				       struct machine *machine,
				       bool mmap_data,
				       unsigned int proc_map_timeout)
{
	char filename[PATH_MAX];
	FILE *fp;
	unsigned long long t;
	bool truncation = false;
	unsigned long long timeout = proc_map_timeout * 1000000ULL;
	int rc = 0;

	if (machine__is_default_guest(machine))
		return 0;

	snprintf(filename, sizeof(filename), "%s/proc/%d/maps",
		 machine->root_dir, 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_MMAP2;
	t = rdclock();

	while (1) {
		char bf[BUFSIZ];
		char prot[5];
		char execname[PATH_MAX];
		char anonstr[] = "//anon";
		unsigned int ino;
		size_t size;
		ssize_t n;

		if (fgets(bf, sizeof(bf), fp) == NULL)
			break;

		if ((rdclock() - t) > timeout) {
			pr_warning("Reading %s time out. "
				   "You may want to increase "
				   "the time limit by --proc-map-timeout\n",
				   filename);
			truncation = true;
			goto out;
		}

		/* ensure null termination since stack will be reused. */
		strcpy(execname, "");

		/* 00400000-0040c000 r-xp 00000000 fd:01 41038  /bin/cat */
		n = sscanf(bf, "%"PRIx64"-%"PRIx64" %s %"PRIx64" %x:%x %u %s\n",
		       &event->mmap2.start, &event->mmap2.len, prot,
		       &event->mmap2.pgoff, &event->mmap2.maj,
		       &event->mmap2.min,
		       &ino, execname);

		/*
 		 * Anon maps don't have the execname.
 		 */
		if (n < 7)
			continue;

		event->mmap2.ino = (u64)ino;

		/*
		 * Just like the kernel, see __perf_event_mmap in kernel/perf_event.c
		 */
		if (machine__is_host(machine))
			event->header.misc = PERF_RECORD_MISC_USER;
		else
			event->header.misc = PERF_RECORD_MISC_GUEST_USER;

		/* map protection and flags bits */
		event->mmap2.prot = 0;
		event->mmap2.flags = 0;
		if (prot[0] == 'r')
			event->mmap2.prot |= PROT_READ;
		if (prot[1] == 'w')
			event->mmap2.prot |= PROT_WRITE;
		if (prot[2] == 'x')
			event->mmap2.prot |= PROT_EXEC;

		if (prot[3] == 's')
			event->mmap2.flags |= MAP_SHARED;
		else
			event->mmap2.flags |= MAP_PRIVATE;

		if (prot[2] != 'x') {
			if (!mmap_data || prot[0] != 'r')
				continue;

			event->header.misc |= PERF_RECORD_MISC_MMAP_DATA;
		}

out:
		if (truncation)
			event->header.misc |= PERF_RECORD_MISC_PROC_MAP_PARSE_TIMEOUT;

		if (!strcmp(execname, ""))
			strcpy(execname, anonstr);

		size = strlen(execname) + 1;
		memcpy(event->mmap2.filename, execname, size);
		size = PERF_ALIGN(size, sizeof(u64));
		event->mmap2.len -= event->mmap.start;
		event->mmap2.header.size = (sizeof(event->mmap2) -
					(sizeof(event->mmap2.filename) - size));
		memset(event->mmap2.filename + size, 0, machine->id_hdr_size);
		event->mmap2.header.size += machine->id_hdr_size;
		event->mmap2.pid = tgid;
		event->mmap2.tid = pid;

		if (process(tool, event, &synth_sample, machine) != 0) {
			rc = -1;
			break;
		}

		if (truncation)
			break;
	}

	fclose(fp);
	return rc;
}

int perf_event__synthesize_modules(struct perf_tool *tool,
				   perf_event__handler_t process,
				   struct machine *machine)
{
	int rc = 0;
	struct map *pos;
	struct map_groups *kmaps = &machine->kmaps;
	struct maps *maps = &kmaps->maps[MAP__FUNCTION];
	union perf_event *event = zalloc((sizeof(event->mmap) +
					  machine->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 (pos = maps__first(maps); pos; pos = map__next(pos)) {
		size_t size;

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

		size = PERF_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, machine->id_hdr_size);
		event->mmap.header.size += machine->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);
		if (process(tool, event, &synth_sample, machine) != 0) {
			rc = -1;
			break;
		}
	}

	free(event);
	return rc;
}

static int __event__synthesize_thread(union perf_event *comm_event,
				      union perf_event *mmap_event,
				      union perf_event *fork_event,
				      pid_t pid, int full,
					  perf_event__handler_t process,
				      struct perf_tool *tool,
				      struct machine *machine,
				      bool mmap_data,
				      unsigned int proc_map_timeout)
{
	char filename[PATH_MAX];
	DIR *tasks;
	struct dirent dirent, *next;
	pid_t tgid, ppid;
	int rc = 0;

	/* special case: only send one comm event using passed in pid */
	if (!full) {
		tgid = perf_event__synthesize_comm(tool, comm_event, pid,
						   process, machine);

		if (tgid == -1)
			return -1;

		return perf_event__synthesize_mmap_events(tool, mmap_event, pid, tgid,
							  process, machine, mmap_data,
							  proc_map_timeout);
	}

	if (machine__is_default_guest(machine))
		return 0;

	snprintf(filename, sizeof(filename), "%s/proc/%d/task",
		 machine->root_dir, pid);

	tasks = opendir(filename);
	if (tasks == NULL) {
		pr_debug("couldn't open %s\n", filename);
		return 0;
	}

	while (!readdir_r(tasks, &dirent, &next) && next) {
		char *end;
		pid_t _pid;

		_pid = strtol(dirent.d_name, &end, 10);
		if (*end)
			continue;

		rc = -1;
		if (perf_event__prepare_comm(comm_event, _pid, machine,
					     &tgid, &ppid) != 0)
			break;

		if (perf_event__synthesize_fork(tool, fork_event, _pid, tgid,
						ppid, process, machine) < 0)
			break;
		/*
		 * Send the prepared comm event
		 */
		if (process(tool, comm_event, &synth_sample, machine) != 0)
			break;

		rc = 0;
		if (_pid == pid) {
			/* process the parent's maps too */
			rc = perf_event__synthesize_mmap_events(tool, mmap_event, pid, tgid,
						process, machine, mmap_data, proc_map_timeout);
			if (rc)
				break;
		}
	}

	closedir(tasks);
	return rc;
}

int perf_event__synthesize_thread_map(struct perf_tool *tool,
				      struct thread_map *threads,
				      perf_event__handler_t process,
				      struct machine *machine,
				      bool mmap_data,
				      unsigned int proc_map_timeout)
{
	union perf_event *comm_event, *mmap_event, *fork_event;
	int err = -1, thread, j;

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

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

	fork_event = malloc(sizeof(fork_event->fork) + machine->id_hdr_size);
	if (fork_event == NULL)
		goto out_free_mmap;

	err = 0;
	for (thread = 0; thread < threads->nr; ++thread) {
		if (__event__synthesize_thread(comm_event, mmap_event,
					       fork_event,
					       thread_map__pid(threads, thread), 0,
					       process, tool, machine,
					       mmap_data, proc_map_timeout)) {
			err = -1;
			break;
		}

		/*
		 * comm.pid is set to thread group id by
		 * perf_event__synthesize_comm
		 */
		if ((int) comm_event->comm.pid != thread_map__pid(threads, thread)) {
			bool need_leader = true;

			/* is thread group leader in thread_map? */
			for (j = 0; j < threads->nr; ++j) {
				if ((int) comm_event->comm.pid == thread_map__pid(threads, j)) {
					need_leader = false;
					break;
				}
			}

			/* if not, generate events for it */
			if (need_leader &&
			    __event__synthesize_thread(comm_event, mmap_event,
						       fork_event,
						       comm_event->comm.pid, 0,
						       process, tool, machine,
						       mmap_data, proc_map_timeout)) {
				err = -1;
				break;
			}
		}
	}
	free(fork_event);
out_free_mmap:
	free(mmap_event);
out_free_comm:
	free(comm_event);
out:
	return err;
}

int perf_event__synthesize_threads(struct perf_tool *tool,
				   perf_event__handler_t process,
				   struct machine *machine,
				   bool mmap_data,
				   unsigned int proc_map_timeout)
{
	DIR *proc;
	char proc_path[PATH_MAX];
	struct dirent dirent, *next;
	union perf_event *comm_event, *mmap_event, *fork_event;
	int err = -1;

	if (machine__is_default_guest(machine))
		return 0;

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

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

	fork_event = malloc(sizeof(fork_event->fork) + machine->id_hdr_size);
	if (fork_event == NULL)
		goto out_free_mmap;

	snprintf(proc_path, sizeof(proc_path), "%s/proc", machine->root_dir);
	proc = opendir(proc_path);

	if (proc == NULL)
		goto out_free_fork;

	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;
		/*
 		 * We may race with exiting thread, so don't stop just because
 		 * one thread couldn't be synthesized.
 		 */
		__event__synthesize_thread(comm_event, mmap_event, fork_event, pid,
					   1, process, tool, machine, mmap_data,
					   proc_map_timeout);
	}

	err = 0;
	closedir(proc);
out_free_fork:
	free(fork_event);
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)
{
	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;
}

u64 kallsyms__get_function_start(const char *kallsyms_filename,
				 const char *symbol_name)
{
	struct process_symbol_args args = { .name = symbol_name, };

	if (kallsyms__parse(kallsyms_filename, &args, find_symbol_cb) <= 0)
		return 0;

	return args.start;
}

int perf_event__synthesize_kernel_mmap(struct perf_tool *tool,
				       perf_event__handler_t process,
				       struct machine *machine)
{
	size_t size;
	const char *mmap_name;
	char name_buff[PATH_MAX];
	struct map *map;
	struct kmap *kmap;
	int err;
	union perf_event *event;

	if (machine->vmlinux_maps[0] == NULL)
		return -1;

	/*
	 * 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.
	 */
	event = zalloc((sizeof(event->mmap) + machine->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;
	} else {
		event->header.misc = PERF_RECORD_MISC_GUEST_KERNEL;
	}

	map = machine->vmlinux_maps[MAP__FUNCTION];
	kmap = map__kmap(map);
	size = snprintf(event->mmap.filename, sizeof(event->mmap.filename),
			"%s%s", mmap_name, kmap->ref_reloc_sym->name) + 1;
	size = PERF_ALIGN(size, sizeof(u64));
	event->mmap.header.type = PERF_RECORD_MMAP;
	event->mmap.header.size = (sizeof(event->mmap) -
			(sizeof(event->mmap.filename) - size) + machine->id_hdr_size);
	event->mmap.pgoff = kmap->ref_reloc_sym->addr;
	event->mmap.start = map->start;
	event->mmap.len   = map->end - event->mmap.start;
	event->mmap.pid   = machine->pid;

	err = process(tool, event, &synth_sample, machine);
	free(event);

	return err;
}

size_t perf_event__fprintf_comm(union perf_event *event, FILE *fp)
{
	const char *s;

	if (event->header.misc & PERF_RECORD_MISC_COMM_EXEC)
		s = " exec";
	else
		s = "";

	return fprintf(fp, "%s: %s:%d/%d\n", s, event->comm.comm, event->comm.pid, event->comm.tid);
}

int perf_event__process_comm(struct perf_tool *tool __maybe_unused,
			     union perf_event *event,
			     struct perf_sample *sample,
			     struct machine *machine)
{
	return machine__process_comm_event(machine, event, sample);
}

int perf_event__process_lost(struct perf_tool *tool __maybe_unused,
			     union perf_event *event,
			     struct perf_sample *sample,
			     struct machine *machine)
{
	return machine__process_lost_event(machine, event, sample);
}

int perf_event__process_aux(struct perf_tool *tool __maybe_unused,
			    union perf_event *event,
			    struct perf_sample *sample __maybe_unused,
			    struct machine *machine)
{
	return machine__process_aux_event(machine, event);
}

int perf_event__process_itrace_start(struct perf_tool *tool __maybe_unused,
				     union perf_event *event,
				     struct perf_sample *sample __maybe_unused,
				     struct machine *machine)
{
	return machine__process_itrace_start_event(machine, event);
}

int perf_event__process_lost_samples(struct perf_tool *tool __maybe_unused,
				     union perf_event *event,
				     struct perf_sample *sample,
				     struct machine *machine)
{
	return machine__process_lost_samples_event(machine, event, sample);
}

int perf_event__process_switch(struct perf_tool *tool __maybe_unused,
			       union perf_event *event,
			       struct perf_sample *sample __maybe_unused,
			       struct machine *machine)
{
	return machine__process_switch_event(machine, event);
}

size_t perf_event__fprintf_mmap(union perf_event *event, FILE *fp)
{
	return fprintf(fp, " %d/%d: [%#" PRIx64 "(%#" PRIx64 ") @ %#" PRIx64 "]: %c %s\n",
		       event->mmap.pid, event->mmap.tid, event->mmap.start,
		       event->mmap.len, event->mmap.pgoff,
		       (event->header.misc & PERF_RECORD_MISC_MMAP_DATA) ? 'r' : 'x',
		       event->mmap.filename);
}

size_t perf_event__fprintf_mmap2(union perf_event *event, FILE *fp)
{
	return fprintf(fp, " %d/%d: [%#" PRIx64 "(%#" PRIx64 ") @ %#" PRIx64
			   " %02x:%02x %"PRIu64" %"PRIu64"]: %c%c%c%c %s\n",
		       event->mmap2.pid, event->mmap2.tid, event->mmap2.start,
		       event->mmap2.len, event->mmap2.pgoff, event->mmap2.maj,
		       event->mmap2.min, event->mmap2.ino,
		       event->mmap2.ino_generation,
		       (event->mmap2.prot & PROT_READ) ? 'r' : '-',
		       (event->mmap2.prot & PROT_WRITE) ? 'w' : '-',
		       (event->mmap2.prot & PROT_EXEC) ? 'x' : '-',
		       (event->mmap2.flags & MAP_SHARED) ? 's' : 'p',
		       event->mmap2.filename);
}

int perf_event__process_mmap(struct perf_tool *tool __maybe_unused,
			     union perf_event *event,
			     struct perf_sample *sample,
			     struct machine *machine)
{
	return machine__process_mmap_event(machine, event, sample);
}

int perf_event__process_mmap2(struct perf_tool *tool __maybe_unused,
			     union perf_event *event,
			     struct perf_sample *sample,
			     struct machine *machine)
{
	return machine__process_mmap2_event(machine, event, sample);
}

size_t perf_event__fprintf_task(union perf_event *event, FILE *fp)
{
	return fprintf(fp, "(%d:%d):(%d:%d)\n",
		       event->fork.pid, event->fork.tid,
		       event->fork.ppid, event->fork.ptid);
}

int perf_event__process_fork(struct perf_tool *tool __maybe_unused,
			     union perf_event *event,
			     struct perf_sample *sample,
			     struct machine *machine)
{
	return machine__process_fork_event(machine, event, sample);
}

int perf_event__process_exit(struct perf_tool *tool __maybe_unused,
			     union perf_event *event,
			     struct perf_sample *sample,
			     struct machine *machine)
{
	return machine__process_exit_event(machine, event, sample);
}

size_t perf_event__fprintf_aux(union perf_event *event, FILE *fp)
{
	return fprintf(fp, " offset: %#"PRIx64" size: %#"PRIx64" flags: %#"PRIx64" [%s%s]\n",
		       event->aux.aux_offset, event->aux.aux_size,
		       event->aux.flags,
		       event->aux.flags & PERF_AUX_FLAG_TRUNCATED ? "T" : "",
		       event->aux.flags & PERF_AUX_FLAG_OVERWRITE ? "O" : "");
}

size_t perf_event__fprintf_itrace_start(union perf_event *event, FILE *fp)
{
	return fprintf(fp, " pid: %u tid: %u\n",
		       event->itrace_start.pid, event->itrace_start.tid);
}

size_t perf_event__fprintf_switch(union perf_event *event, FILE *fp)
{
	bool out = event->header.misc & PERF_RECORD_MISC_SWITCH_OUT;
	const char *in_out = out ? "OUT" : "IN ";

	if (event->header.type == PERF_RECORD_SWITCH)
		return fprintf(fp, " %s\n", in_out);

	return fprintf(fp, " %s  %s pid/tid: %5u/%-5u\n",
		       in_out, out ? "next" : "prev",
		       event->context_switch.next_prev_pid,
		       event->context_switch.next_prev_tid);
}

size_t perf_event__fprintf(union perf_event *event, FILE *fp)
{
	size_t ret = fprintf(fp, "PERF_RECORD_%s",
			     perf_event__name(event->header.type));

	switch (event->header.type) {
	case PERF_RECORD_COMM:
		ret += perf_event__fprintf_comm(event, fp);
		break;
	case PERF_RECORD_FORK:
	case PERF_RECORD_EXIT:
		ret += perf_event__fprintf_task(event, fp);
		break;
	case PERF_RECORD_MMAP:
		ret += perf_event__fprintf_mmap(event, fp);
		break;
	case PERF_RECORD_MMAP2:
		ret += perf_event__fprintf_mmap2(event, fp);
		break;
	case PERF_RECORD_AUX:
		ret += perf_event__fprintf_aux(event, fp);
		break;
	case PERF_RECORD_ITRACE_START:
		ret += perf_event__fprintf_itrace_start(event, fp);
		break;
	case PERF_RECORD_SWITCH:
	case PERF_RECORD_SWITCH_CPU_WIDE:
		ret += perf_event__fprintf_switch(event, fp);
		break;
	default:
		ret += fprintf(fp, "\n");
	}

	return ret;
}

int perf_event__process(struct perf_tool *tool __maybe_unused,
			union perf_event *event,
			struct perf_sample *sample,
			struct machine *machine)
{
	return machine__process_event(machine, event, sample);
}

void thread__find_addr_map(struct thread *thread, u8 cpumode,
			   enum map_type type, u64 addr,
			   struct addr_location *al)
{
	struct map_groups *mg = thread->mg;
	struct machine *machine = mg->machine;
	bool load_map = false;

	al->machine = machine;
	al->thread = thread;
	al->addr = addr;
	al->cpumode = cpumode;
	al->filtered = 0;

	if (machine == NULL) {
		al->map = NULL;
		return;
	}

	if (cpumode == PERF_RECORD_MISC_KERNEL && perf_host) {
		al->level = 'k';
		mg = &machine->kmaps;
		load_map = true;
	} else if (cpumode == PERF_RECORD_MISC_USER && perf_host) {
		al->level = '.';
	} else if (cpumode == PERF_RECORD_MISC_GUEST_KERNEL && perf_guest) {
		al->level = 'g';
		mg = &machine->kmaps;
		load_map = true;
	} else 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 |= (1 << HIST_FILTER__GUEST);
		if ((cpumode == PERF_RECORD_MISC_USER ||
			cpumode == PERF_RECORD_MISC_KERNEL) &&
			!perf_host)
			al->filtered |= (1 << HIST_FILTER__HOST);

		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 (cpumode == PERF_RECORD_MISC_USER && machine &&
		    mg != &machine->kmaps &&
		    machine__kernel_ip(machine, al->addr)) {
			mg = &machine->kmaps;
			load_map = true;
			goto try_again;
		}
	} else {
		/*
		 * Kernel maps might be changed when loading symbols so loading
		 * must be done prior to using kernel maps.
		 */
		if (load_map)
			map__load(al->map, machine->symbol_filter);
		al->addr = al->map->map_ip(al->map, al->addr);
	}
}

void thread__find_addr_location(struct thread *thread,
				u8 cpumode, enum map_type type, u64 addr,
				struct addr_location *al)
{
	thread__find_addr_map(thread, cpumode, type, addr, al);
	if (al->map != NULL)
		al->sym = map__find_symbol(al->map, al->addr,
					   thread->mg->machine->symbol_filter);
	else
		al->sym = NULL;
}

/*
 * Callers need to drop the reference to al->thread, obtained in
 * machine__findnew_thread()
 */
int perf_event__preprocess_sample(const union perf_event *event,
				  struct machine *machine,
				  struct addr_location *al,
				  struct perf_sample *sample)
{
	u8 cpumode = event->header.misc & PERF_RECORD_MISC_CPUMODE_MASK;
	struct thread *thread = machine__findnew_thread(machine, sample->pid,
							sample->tid);

	if (thread == NULL)
		return -1;

	dump_printf(" ... thread: %s:%d\n", thread__comm_str(thread), thread->tid);
	/*
	 * Have we already created the kernel maps for this 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 &&
	    machine->vmlinux_maps[MAP__FUNCTION] == NULL)
		machine__create_kernel_maps(machine);

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

	if (thread__is_filtered(thread))
		al->filtered |= (1 << HIST_FILTER__THREAD);

	al->sym = NULL;
	al->cpu = sample->cpu;

	if (al->map) {
		struct dso *dso = al->map->dso;

		if (symbol_conf.dso_list &&
		    (!dso || !(strlist__has_entry(symbol_conf.dso_list,
						  dso->short_name) ||
			       (dso->short_name != dso->long_name &&
				strlist__has_entry(symbol_conf.dso_list,
						   dso->long_name))))) {
			al->filtered |= (1 << HIST_FILTER__DSO);
		}

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

	if (symbol_conf.sym_list &&
		(!al->sym || !strlist__has_entry(symbol_conf.sym_list,
						al->sym->name))) {
		al->filtered |= (1 << HIST_FILTER__SYMBOL);
	}

	return 0;
}

/*
 * The preprocess_sample method will return with reference counts for the
 * in it, when done using (and perhaps getting ref counts if needing to
 * keep a pointer to one of those entries) it must be paired with
 * addr_location__put(), so that the refcounts can be decremented.
 */
void addr_location__put(struct addr_location *al)
{
	thread__zput(al->thread);
}

bool is_bts_event(struct perf_event_attr *attr)
{
	return attr->type == PERF_TYPE_HARDWARE &&
	       (attr->config & PERF_COUNT_HW_BRANCH_INSTRUCTIONS) &&
	       attr->sample_period == 1;
}

bool sample_addr_correlates_sym(struct perf_event_attr *attr)
{
	if (attr->type == PERF_TYPE_SOFTWARE &&
	    (attr->config == PERF_COUNT_SW_PAGE_FAULTS ||
	     attr->config == PERF_COUNT_SW_PAGE_FAULTS_MIN ||
	     attr->config == PERF_COUNT_SW_PAGE_FAULTS_MAJ))
		return true;

	if (is_bts_event(attr))
		return true;

	return false;
}

void perf_event__preprocess_sample_addr(union perf_event *event,
					struct perf_sample *sample,
					struct thread *thread,
					struct addr_location *al)
{
	u8 cpumode = event->header.misc & PERF_RECORD_MISC_CPUMODE_MASK;

	thread__find_addr_map(thread, cpumode, MAP__FUNCTION, sample->addr, al);
	if (!al->map)
		thread__find_addr_map(thread, cpumode, MAP__VARIABLE,
				      sample->addr, al);

	al->cpu = sample->cpu;
	al->sym = NULL;

	if (al->map)
		al->sym = map__find_symbol(al->map, al->addr, NULL);
}
OpenPOWER on IntegriCloud