summaryrefslogtreecommitdiffstats
path: root/tools/perf/util/s390-cpumsf.c
blob: 08073a4d59a40cd958c51afe5dc7b86e10502051 (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
// SPDX-License-Identifier: GPL-2.0
/*
 * Copyright IBM Corp. 2018
 * Auxtrace support for s390 CPU-Measurement Sampling Facility
 *
 * Author(s):  Thomas Richter <tmricht@linux.ibm.com>
 *
 * Auxiliary traces are collected during 'perf record' using rbd000 event.
 * Several PERF_RECORD_XXX are generated during recording:
 *
 * PERF_RECORD_AUX:
 *	Records that new data landed in the AUX buffer part.
 * PERF_RECORD_AUXTRACE:
 *	Defines auxtrace data. Followed by the actual data. The contents of
 *	the auxtrace data is dependent on the event and the CPU.
 *	This record is generated by perf record command. For details
 *	see Documentation/perf.data-file-format.txt.
 * PERF_RECORD_AUXTRACE_INFO:
 *	Defines a table of contains for PERF_RECORD_AUXTRACE records. This
 *	record is generated during 'perf record' command. Each record contains up
 *	to 256 entries describing offset and size of the AUXTRACE data in the
 *	perf.data file.
 * PERF_RECORD_AUXTRACE_ERROR:
 *	Indicates an error during AUXTRACE collection such as buffer overflow.
 * PERF_RECORD_FINISHED_ROUND:
 *	Perf events are not necessarily in time stamp order, as they can be
 *	collected in parallel on different CPUs. If the events should be
 *	processed in time order they need to be sorted first.
 *	Perf report guarantees that there is no reordering over a
 *	PERF_RECORD_FINISHED_ROUND boundary event. All perf records with a
 *	time stamp lower than this record are processed (and displayed) before
 *	the succeeding perf record are processed.
 *
 * These records are evaluated during perf report command.
 *
 * 1. PERF_RECORD_AUXTRACE_INFO is used to set up the infrastructure for
 * auxiliary trace data processing. See s390_cpumsf_process_auxtrace_info()
 * below.
 * Auxiliary trace data is collected per CPU. To merge the data into the report
 * an auxtrace_queue is created for each CPU. It is assumed that the auxtrace
 * data is in ascending order.
 *
 * Each queue has a double linked list of auxtrace_buffers. This list contains
 * the offset and size of a CPU's auxtrace data. During auxtrace processing
 * the data portion is mmap()'ed.
 *
 * To sort the queues in chronological order, all queue access is controlled
 * by the auxtrace_heap. This is basicly a stack, each stack element has two
 * entries, the queue number and a time stamp. However the stack is sorted by
 * the time stamps. The highest time stamp is at the bottom the lowest
 * (nearest) time stamp is at the top. That sort order is maintained at all
 * times!
 *
 * After the auxtrace infrastructure has been setup, the auxtrace queues are
 * filled with data (offset/size pairs) and the auxtrace_heap is populated.
 *
 * 2. PERF_RECORD_XXX processing triggers access to the auxtrace_queues.
 * Each record is handled by s390_cpumsf_process_event(). The time stamp of
 * the perf record is compared with the time stamp located on the auxtrace_heap
 * top element. If that time stamp is lower than the time stamp from the
 * record sample, the auxtrace queues will be processed. As auxtrace queues
 * control many auxtrace_buffers and each buffer can be quite large, the
 * auxtrace buffer might be processed only partially. In this case the
 * position in the auxtrace_buffer of that queue is remembered and the time
 * stamp of the last processed entry of the auxtrace_buffer replaces the
 * current auxtrace_heap top.
 *
 * 3. Auxtrace_queues might run of out data and are feeded by the
 * PERF_RECORD_AUXTRACE handling, see s390_cpumsf_process_auxtrace_event().
 *
 * Event Generation
 * Each sampling-data entry in the auxilary trace data generates a perf sample.
 * This sample is filled
 * with data from the auxtrace such as PID/TID, instruction address, CPU state,
 * etc. This sample is processed with perf_session__deliver_synth_event() to
 * be included into the GUI.
 *
 * 4. PERF_RECORD_FINISHED_ROUND event is used to process all the remaining
 * auxiliary traces entries until the time stamp of this record is reached
 * auxtrace_heap top. This is triggered by ordered_event->deliver().
 *
 *
 * Perf event processing.
 * Event processing of PERF_RECORD_XXX entries relies on time stamp entries.
 * This is the function call sequence:
 *
 * __cmd_report()
 * |
 * perf_session__process_events()
 * |
 * __perf_session__process_events()
 * |
 * perf_session__process_event()
 * |  This functions splits the PERF_RECORD_XXX records.
 * |  - Those generated by perf record command (type number equal or higher
 * |    than PERF_RECORD_USER_TYPE_START) are handled by
 * |    perf_session__process_user_event(see below)
 * |  - Those generated by the kernel are handled by
 * |    perf_evlist__parse_sample_timestamp()
 * |
 * perf_evlist__parse_sample_timestamp()
 * |  Extract time stamp from sample data.
 * |
 * perf_session__queue_event()
 * |  If timestamp is positive the sample is entered into an ordered_event
 * |  list, sort order is the timestamp. The event processing is deferred until
 * |  later (see perf_session__process_user_event()).
 * |  Other timestamps (0 or -1) are handled immediately by
 * |  perf_session__deliver_event(). These are events generated at start up
 * |  of command perf record. They create PERF_RECORD_COMM and PERF_RECORD_MMAP*
 * |  records. They are needed to create a list of running processes and its
 * |  memory mappings and layout. They are needed at the beginning to enable
 * |  command perf report to create process trees and memory mappings.
 * |
 * perf_session__deliver_event()
 * |  Delivers a PERF_RECORD_XXX entry for handling.
 * |
 * auxtrace__process_event()
 * |  The timestamp of the PERF_RECORD_XXX entry is taken to correlate with
 * |  time stamps from the auxiliary trace buffers. This enables
 * |  synchronization between auxiliary trace data and the events on the
 * |  perf.data file.
 * |
 * machine__deliver_event()
 * |  Handles the PERF_RECORD_XXX event. This depends on the record type.
 *    It might update the process tree, update a process memory map or enter
 *    a sample with IP and call back chain data into GUI data pool.
 *
 *
 * Deferred processing determined by perf_session__process_user_event() is
 * finally processed when a PERF_RECORD_FINISHED_ROUND is encountered. These
 * are generated during command perf record.
 * The timestamp of PERF_RECORD_FINISHED_ROUND event is taken to process all
 * PERF_RECORD_XXX entries stored in the ordered_event list. This list was
 * built up while reading the perf.data file.
 * Each event is now processed by calling perf_session__deliver_event().
 * This enables time synchronization between the data in the perf.data file and
 * the data in the auxiliary trace buffers.
 */

#include <endian.h>
#include <errno.h>
#include <byteswap.h>
#include <inttypes.h>
#include <linux/kernel.h>
#include <linux/types.h>
#include <linux/bitops.h>
#include <linux/log2.h>

#include <sys/stat.h>
#include <sys/types.h>

#include "cpumap.h"
#include "color.h"
#include "evsel.h"
#include "evlist.h"
#include "machine.h"
#include "session.h"
#include "util.h"
#include "thread.h"
#include "debug.h"
#include "auxtrace.h"
#include "s390-cpumsf.h"
#include "s390-cpumsf-kernel.h"
#include "config.h"

struct s390_cpumsf {
	struct auxtrace		auxtrace;
	struct auxtrace_queues	queues;
	struct auxtrace_heap	heap;
	struct perf_session	*session;
	struct machine		*machine;
	u32			auxtrace_type;
	u32			pmu_type;
	u16			machine_type;
	bool			data_queued;
	bool			use_logfile;
	char			*logdir;
};

struct s390_cpumsf_queue {
	struct s390_cpumsf	*sf;
	unsigned int		queue_nr;
	struct auxtrace_buffer	*buffer;
	int			cpu;
	FILE			*logfile;
};

/* Display s390 CPU measurement facility basic-sampling data entry */
static bool s390_cpumsf_basic_show(const char *color, size_t pos,
				   struct hws_basic_entry *basic)
{
	if (basic->def != 1) {
		pr_err("Invalid AUX trace basic entry [%#08zx]\n", pos);
		return false;
	}
	color_fprintf(stdout, color, "    [%#08zx] Basic   Def:%04x Inst:%#04x"
		      " %c%c%c%c AS:%d ASN:%#04x IA:%#018llx\n"
		      "\t\tCL:%d HPP:%#018llx GPP:%#018llx\n",
		      pos, basic->def, basic->U,
		      basic->T ? 'T' : ' ',
		      basic->W ? 'W' : ' ',
		      basic->P ? 'P' : ' ',
		      basic->I ? 'I' : ' ',
		      basic->AS, basic->prim_asn, basic->ia, basic->CL,
		      basic->hpp, basic->gpp);
	return true;
}

/* Display s390 CPU measurement facility diagnostic-sampling data entry */
static bool s390_cpumsf_diag_show(const char *color, size_t pos,
				  struct hws_diag_entry *diag)
{
	if (diag->def < S390_CPUMSF_DIAG_DEF_FIRST) {
		pr_err("Invalid AUX trace diagnostic entry [%#08zx]\n", pos);
		return false;
	}
	color_fprintf(stdout, color, "    [%#08zx] Diag    Def:%04x %c\n",
		      pos, diag->def, diag->I ? 'I' : ' ');
	return true;
}

/* Return TOD timestamp contained in an trailer entry */
static unsigned long long trailer_timestamp(struct hws_trailer_entry *te)
{
	/* te->t set: TOD in STCKE format, bytes 8-15
	 * to->t not set: TOD in STCK format, bytes 0-7
	 */
	unsigned long long ts;

	memcpy(&ts, &te->timestamp[te->t], sizeof(ts));
	return ts;
}

/* Display s390 CPU measurement facility trailer entry */
static bool s390_cpumsf_trailer_show(const char *color, size_t pos,
				     struct hws_trailer_entry *te)
{
	if (te->bsdes != sizeof(struct hws_basic_entry)) {
		pr_err("Invalid AUX trace trailer entry [%#08zx]\n", pos);
		return false;
	}
	color_fprintf(stdout, color, "    [%#08zx] Trailer %c%c%c bsdes:%d"
		      " dsdes:%d Overflow:%lld Time:%#llx\n"
		      "\t\tC:%d TOD:%#lx 1:%#llx 2:%#llx\n",
		      pos,
		      te->f ? 'F' : ' ',
		      te->a ? 'A' : ' ',
		      te->t ? 'T' : ' ',
		      te->bsdes, te->dsdes, te->overflow,
		      trailer_timestamp(te), te->clock_base, te->progusage2,
		      te->progusage[0], te->progusage[1]);
	return true;
}

/* Test a sample data block. It must be 4KB or a multiple thereof in size and
 * 4KB page aligned. Each sample data page has a trailer entry at the
 * end which contains the sample entry data sizes.
 *
 * Return true if the sample data block passes the checks and set the
 * basic set entry size and diagnostic set entry size.
 *
 * Return false on failure.
 *
 * Note: Old hardware does not set the basic or diagnostic entry sizes
 * in the trailer entry. Use the type number instead.
 */
static bool s390_cpumsf_validate(int machine_type,
				 unsigned char *buf, size_t len,
				 unsigned short *bsdes,
				 unsigned short *dsdes)
{
	struct hws_basic_entry *basic = (struct hws_basic_entry *)buf;
	struct hws_trailer_entry *te;

	*dsdes = *bsdes = 0;
	if (len & (S390_CPUMSF_PAGESZ - 1))	/* Illegal size */
		return false;
	if (basic->def != 1)		/* No basic set entry, must be first */
		return false;
	/* Check for trailer entry at end of SDB */
	te = (struct hws_trailer_entry *)(buf + S390_CPUMSF_PAGESZ
					      - sizeof(*te));
	*bsdes = te->bsdes;
	*dsdes = te->dsdes;
	if (!te->bsdes && !te->dsdes) {
		/* Very old hardware, use CPUID */
		switch (machine_type) {
		case 2097:
		case 2098:
			*dsdes = 64;
			*bsdes = 32;
			break;
		case 2817:
		case 2818:
			*dsdes = 74;
			*bsdes = 32;
			break;
		case 2827:
		case 2828:
			*dsdes = 85;
			*bsdes = 32;
			break;
		case 2964:
		case 2965:
			*dsdes = 112;
			*bsdes = 32;
			break;
		default:
			/* Illegal trailer entry */
			return false;
		}
	}
	return true;
}

/* Return true if there is room for another entry */
static bool s390_cpumsf_reached_trailer(size_t entry_sz, size_t pos)
{
	size_t payload = S390_CPUMSF_PAGESZ - sizeof(struct hws_trailer_entry);

	if (payload - (pos & (S390_CPUMSF_PAGESZ - 1)) < entry_sz)
		return false;
	return true;
}

/* Dump an auxiliary buffer. These buffers are multiple of
 * 4KB SDB pages.
 */
static void s390_cpumsf_dump(struct s390_cpumsf *sf,
			     unsigned char *buf, size_t len)
{
	const char *color = PERF_COLOR_BLUE;
	struct hws_basic_entry *basic;
	struct hws_diag_entry *diag;
	unsigned short bsdes, dsdes;
	size_t pos = 0;

	color_fprintf(stdout, color,
		      ". ... s390 AUX data: size %zu bytes\n",
		      len);

	if (!s390_cpumsf_validate(sf->machine_type, buf, len, &bsdes,
				  &dsdes)) {
		pr_err("Invalid AUX trace data block size:%zu"
		       " (type:%d bsdes:%hd dsdes:%hd)\n",
		       len, sf->machine_type, bsdes, dsdes);
		return;
	}

	/* s390 kernel always returns 4KB blocks fully occupied,
	 * no partially filled SDBs.
	 */
	while (pos < len) {
		/* Handle Basic entry */
		basic = (struct hws_basic_entry *)(buf + pos);
		if (s390_cpumsf_basic_show(color, pos, basic))
			pos += bsdes;
		else
			return;

		/* Handle Diagnostic entry */
		diag = (struct hws_diag_entry *)(buf + pos);
		if (s390_cpumsf_diag_show(color, pos, diag))
			pos += dsdes;
		else
			return;

		/* Check for trailer entry */
		if (!s390_cpumsf_reached_trailer(bsdes + dsdes, pos)) {
			/* Show trailer entry */
			struct hws_trailer_entry te;

			pos = (pos + S390_CPUMSF_PAGESZ)
			       & ~(S390_CPUMSF_PAGESZ - 1);
			pos -= sizeof(te);
			memcpy(&te, buf + pos, sizeof(te));
			/* Set descriptor sizes in case of old hardware
			 * where these values are not set.
			 */
			te.bsdes = bsdes;
			te.dsdes = dsdes;
			if (s390_cpumsf_trailer_show(color, pos, &te))
				pos += sizeof(te);
			else
				return;
		}
	}
}

static void s390_cpumsf_dump_event(struct s390_cpumsf *sf, unsigned char *buf,
				   size_t len)
{
	printf(".\n");
	s390_cpumsf_dump(sf, buf, len);
}

#define	S390_LPP_PID_MASK	0xffffffff

static bool s390_cpumsf_make_event(size_t pos,
				   struct hws_basic_entry *basic,
				   struct s390_cpumsf_queue *sfq)
{
	struct perf_sample sample = {
				.ip = basic->ia,
				.pid = basic->hpp & S390_LPP_PID_MASK,
				.tid = basic->hpp & S390_LPP_PID_MASK,
				.cpumode = PERF_RECORD_MISC_CPUMODE_UNKNOWN,
				.cpu = sfq->cpu,
				.period = 1
			    };
	union perf_event event;

	memset(&event, 0, sizeof(event));
	if (basic->CL == 1)	/* Native LPAR mode */
		sample.cpumode = basic->P ? PERF_RECORD_MISC_USER
					  : PERF_RECORD_MISC_KERNEL;
	else if (basic->CL == 2)	/* Guest kernel/user space */
		sample.cpumode = basic->P ? PERF_RECORD_MISC_GUEST_USER
					  : PERF_RECORD_MISC_GUEST_KERNEL;
	else if (basic->gpp || basic->prim_asn != 0xffff)
		/* Use heuristics on old hardware */
		sample.cpumode = basic->P ? PERF_RECORD_MISC_GUEST_USER
					  : PERF_RECORD_MISC_GUEST_KERNEL;
	else
		sample.cpumode = basic->P ? PERF_RECORD_MISC_USER
					  : PERF_RECORD_MISC_KERNEL;

	event.sample.header.type = PERF_RECORD_SAMPLE;
	event.sample.header.misc = sample.cpumode;
	event.sample.header.size = sizeof(struct perf_event_header);

	pr_debug4("%s pos:%#zx ip:%#" PRIx64 " P:%d CL:%d pid:%d.%d cpumode:%d cpu:%d\n",
		 __func__, pos, sample.ip, basic->P, basic->CL, sample.pid,
		 sample.tid, sample.cpumode, sample.cpu);
	if (perf_session__deliver_synth_event(sfq->sf->session, &event,
					      &sample)) {
		pr_err("s390 Auxiliary Trace: failed to deliver event\n");
		return false;
	}
	return true;
}

static unsigned long long get_trailer_time(const unsigned char *buf)
{
	struct hws_trailer_entry *te;
	unsigned long long aux_time;

	te = (struct hws_trailer_entry *)(buf + S390_CPUMSF_PAGESZ
					      - sizeof(*te));

	if (!te->clock_base)	/* TOD_CLOCK_BASE value missing */
		return 0;

	/* Correct calculation to convert time stamp in trailer entry to
	 * nano seconds (taken from arch/s390 function tod_to_ns()).
	 * TOD_CLOCK_BASE is stored in trailer entry member progusage2.
	 */
	aux_time = trailer_timestamp(te) - te->progusage2;
	aux_time = (aux_time >> 9) * 125 + (((aux_time & 0x1ff) * 125) >> 9);
	return aux_time;
}

/* Process the data samples of a single queue. The first parameter is a
 * pointer to the queue, the second parameter is the time stamp. This
 * is the time stamp:
 * - of the event that triggered this processing.
 * - or the time stamp when the last proccesing of this queue stopped.
 *   In this case it stopped at a 4KB page boundary and record the
 *   position on where to continue processing on the next invocation
 *   (see buffer->use_data and buffer->use_size).
 *
 * When this function returns the second parameter is updated to
 * reflect the time stamp of the last processed auxiliary data entry
 * (taken from the trailer entry of that page). The caller uses this
 * returned time stamp to record the last processed entry in this
 * queue.
 *
 * The function returns:
 * 0:  Processing successful. The second parameter returns the
 *     time stamp from the trailer entry until which position
 *     processing took place. Subsequent calls resume from this
 *     position.
 * <0: An error occurred during processing. The second parameter
 *     returns the maximum time stamp.
 * >0: Done on this queue. The second parameter returns the
 *     maximum time stamp.
 */
static int s390_cpumsf_samples(struct s390_cpumsf_queue *sfq, u64 *ts)
{
	struct s390_cpumsf *sf = sfq->sf;
	unsigned char *buf = sfq->buffer->use_data;
	size_t len = sfq->buffer->use_size;
	struct hws_basic_entry *basic;
	unsigned short bsdes, dsdes;
	size_t pos = 0;
	int err = 1;
	u64 aux_ts;

	if (!s390_cpumsf_validate(sf->machine_type, buf, len, &bsdes,
				  &dsdes)) {
		*ts = ~0ULL;
		return -1;
	}

	/* Get trailer entry time stamp and check if entries in
	 * this auxiliary page are ready for processing. If the
	 * time stamp of the first entry is too high, whole buffer
	 * can be skipped. In this case return time stamp.
	 */
	aux_ts = get_trailer_time(buf);
	if (!aux_ts) {
		pr_err("[%#08" PRIx64 "] Invalid AUX trailer entry TOD clock base\n",
		       (s64)sfq->buffer->data_offset);
		aux_ts = ~0ULL;
		goto out;
	}
	if (aux_ts > *ts) {
		*ts = aux_ts;
		return 0;
	}

	while (pos < len) {
		/* Handle Basic entry */
		basic = (struct hws_basic_entry *)(buf + pos);
		if (s390_cpumsf_make_event(pos, basic, sfq))
			pos += bsdes;
		else {
			err = -EBADF;
			goto out;
		}

		pos += dsdes;	/* Skip diagnositic entry */

		/* Check for trailer entry */
		if (!s390_cpumsf_reached_trailer(bsdes + dsdes, pos)) {
			pos = (pos + S390_CPUMSF_PAGESZ)
			       & ~(S390_CPUMSF_PAGESZ - 1);
			/* Check existence of next page */
			if (pos >= len)
				break;
			aux_ts = get_trailer_time(buf + pos);
			if (!aux_ts) {
				aux_ts = ~0ULL;
				goto out;
			}
			if (aux_ts > *ts) {
				*ts = aux_ts;
				sfq->buffer->use_data += pos;
				sfq->buffer->use_size -= pos;
				return 0;
			}
		}
	}
out:
	*ts = aux_ts;
	sfq->buffer->use_size = 0;
	sfq->buffer->use_data = NULL;
	return err;	/* Buffer completely scanned or error */
}

/* Run the s390 auxiliary trace decoder.
 * Select the queue buffer to operate on, the caller already selected
 * the proper queue, depending on second parameter 'ts'.
 * This is the time stamp until which the auxiliary entries should
 * be processed. This value is updated by called functions and
 * returned to the caller.
 *
 * Resume processing in the current buffer. If there is no buffer
 * get a new buffer from the queue and setup start position for
 * processing.
 * When a buffer is completely processed remove it from the queue
 * before returning.
 *
 * This function returns
 * 1: When the queue is empty. Second parameter will be set to
 *    maximum time stamp.
 * 0: Normal processing done.
 * <0: Error during queue buffer setup. This causes the caller
 *     to stop processing completely.
 */
static int s390_cpumsf_run_decoder(struct s390_cpumsf_queue *sfq,
				   u64 *ts)
{

	struct auxtrace_buffer *buffer;
	struct auxtrace_queue *queue;
	int err;

	queue = &sfq->sf->queues.queue_array[sfq->queue_nr];

	/* Get buffer and last position in buffer to resume
	 * decoding the auxiliary entries. One buffer might be large
	 * and decoding might stop in between. This depends on the time
	 * stamp of the trailer entry in each page of the auxiliary
	 * data and the time stamp of the event triggering the decoding.
	 */
	if (sfq->buffer == NULL) {
		sfq->buffer = buffer = auxtrace_buffer__next(queue,
							     sfq->buffer);
		if (!buffer) {
			*ts = ~0ULL;
			return 1;	/* Processing done on this queue */
		}
		/* Start with a new buffer on this queue */
		if (buffer->data) {
			buffer->use_size = buffer->size;
			buffer->use_data = buffer->data;
		}
		if (sfq->logfile) {	/* Write into log file */
			size_t rc = fwrite(buffer->data, buffer->size, 1,
					   sfq->logfile);
			if (rc != 1)
				pr_err("Failed to write auxiliary data\n");
		}
	} else
		buffer = sfq->buffer;

	if (!buffer->data) {
		int fd = perf_data__fd(sfq->sf->session->data);

		buffer->data = auxtrace_buffer__get_data(buffer, fd);
		if (!buffer->data)
			return -ENOMEM;
		buffer->use_size = buffer->size;
		buffer->use_data = buffer->data;

		if (sfq->logfile) {	/* Write into log file */
			size_t rc = fwrite(buffer->data, buffer->size, 1,
					   sfq->logfile);
			if (rc != 1)
				pr_err("Failed to write auxiliary data\n");
		}
	}
	pr_debug4("%s queue_nr:%d buffer:%" PRId64 " offset:%#" PRIx64 " size:%#zx rest:%#zx\n",
		  __func__, sfq->queue_nr, buffer->buffer_nr, buffer->offset,
		  buffer->size, buffer->use_size);
	err = s390_cpumsf_samples(sfq, ts);

	/* If non-zero, there is either an error (err < 0) or the buffer is
	 * completely done (err > 0). The error is unrecoverable, usually
	 * some descriptors could not be read successfully, so continue with
	 * the next buffer.
	 * In both cases the parameter 'ts' has been updated.
	 */
	if (err) {
		sfq->buffer = NULL;
		list_del(&buffer->list);
		auxtrace_buffer__free(buffer);
		if (err > 0)		/* Buffer done, no error */
			err = 0;
	}
	return err;
}

static struct s390_cpumsf_queue *
s390_cpumsf_alloc_queue(struct s390_cpumsf *sf, unsigned int queue_nr)
{
	struct s390_cpumsf_queue *sfq;

	sfq = zalloc(sizeof(struct s390_cpumsf_queue));
	if (sfq == NULL)
		return NULL;

	sfq->sf = sf;
	sfq->queue_nr = queue_nr;
	sfq->cpu = -1;
	if (sf->use_logfile) {
		char *name;
		int rc;

		rc = (sf->logdir)
			? asprintf(&name, "%s/aux.smp.%02x",
				 sf->logdir, queue_nr)
			: asprintf(&name, "aux.smp.%02x", queue_nr);
		if (rc > 0)
			sfq->logfile = fopen(name, "w");
		if (sfq->logfile == NULL) {
			pr_err("Failed to open auxiliary log file %s,"
			       "continue...\n", name);
			sf->use_logfile = false;
		}
		free(name);
	}
	return sfq;
}

static int s390_cpumsf_setup_queue(struct s390_cpumsf *sf,
				   struct auxtrace_queue *queue,
				   unsigned int queue_nr, u64 ts)
{
	struct s390_cpumsf_queue *sfq = queue->priv;

	if (list_empty(&queue->head))
		return 0;

	if (sfq == NULL) {
		sfq = s390_cpumsf_alloc_queue(sf, queue_nr);
		if (!sfq)
			return -ENOMEM;
		queue->priv = sfq;

		if (queue->cpu != -1)
			sfq->cpu = queue->cpu;
	}
	return auxtrace_heap__add(&sf->heap, queue_nr, ts);
}

static int s390_cpumsf_setup_queues(struct s390_cpumsf *sf, u64 ts)
{
	unsigned int i;
	int ret = 0;

	for (i = 0; i < sf->queues.nr_queues; i++) {
		ret = s390_cpumsf_setup_queue(sf, &sf->queues.queue_array[i],
					      i, ts);
		if (ret)
			break;
	}
	return ret;
}

static int s390_cpumsf_update_queues(struct s390_cpumsf *sf, u64 ts)
{
	if (!sf->queues.new_data)
		return 0;

	sf->queues.new_data = false;
	return s390_cpumsf_setup_queues(sf, ts);
}

static int s390_cpumsf_process_queues(struct s390_cpumsf *sf, u64 timestamp)
{
	unsigned int queue_nr;
	u64 ts;
	int ret;

	while (1) {
		struct auxtrace_queue *queue;
		struct s390_cpumsf_queue *sfq;

		if (!sf->heap.heap_cnt)
			return 0;

		if (sf->heap.heap_array[0].ordinal >= timestamp)
			return 0;

		queue_nr = sf->heap.heap_array[0].queue_nr;
		queue = &sf->queues.queue_array[queue_nr];
		sfq = queue->priv;

		auxtrace_heap__pop(&sf->heap);
		if (sf->heap.heap_cnt) {
			ts = sf->heap.heap_array[0].ordinal + 1;
			if (ts > timestamp)
				ts = timestamp;
		} else {
			ts = timestamp;
		}

		ret = s390_cpumsf_run_decoder(sfq, &ts);
		if (ret < 0) {
			auxtrace_heap__add(&sf->heap, queue_nr, ts);
			return ret;
		}
		if (!ret) {
			ret = auxtrace_heap__add(&sf->heap, queue_nr, ts);
			if (ret < 0)
				return ret;
		}
	}
	return 0;
}

static int s390_cpumsf_synth_error(struct s390_cpumsf *sf, int code, int cpu,
				   pid_t pid, pid_t tid, u64 ip)
{
	char msg[MAX_AUXTRACE_ERROR_MSG];
	union perf_event event;
	int err;

	strncpy(msg, "Lost Auxiliary Trace Buffer", sizeof(msg) - 1);
	auxtrace_synth_error(&event.auxtrace_error, PERF_AUXTRACE_ERROR_ITRACE,
			     code, cpu, pid, tid, ip, msg);

	err = perf_session__deliver_synth_event(sf->session, &event, NULL);
	if (err)
		pr_err("s390 Auxiliary Trace: failed to deliver error event,"
			"error %d\n", err);
	return err;
}

static int s390_cpumsf_lost(struct s390_cpumsf *sf, struct perf_sample *sample)
{
	return s390_cpumsf_synth_error(sf, 1, sample->cpu,
				       sample->pid, sample->tid, 0);
}

static int
s390_cpumsf_process_event(struct perf_session *session __maybe_unused,
			  union perf_event *event,
			  struct perf_sample *sample,
			  struct perf_tool *tool)
{
	struct s390_cpumsf *sf = container_of(session->auxtrace,
					      struct s390_cpumsf,
					      auxtrace);
	u64 timestamp = sample->time;
	int err = 0;

	if (dump_trace)
		return 0;

	if (!tool->ordered_events) {
		pr_err("s390 Auxiliary Trace requires ordered events\n");
		return -EINVAL;
	}

	if (event->header.type == PERF_RECORD_AUX &&
	    event->aux.flags & PERF_AUX_FLAG_TRUNCATED)
		return s390_cpumsf_lost(sf, sample);

	if (timestamp) {
		err = s390_cpumsf_update_queues(sf, timestamp);
		if (!err)
			err = s390_cpumsf_process_queues(sf, timestamp);
	}
	return err;
}

struct s390_cpumsf_synth {
	struct perf_tool cpumsf_tool;
	struct perf_session *session;
};

static int
s390_cpumsf_process_auxtrace_event(struct perf_session *session,
				   union perf_event *event __maybe_unused,
				   struct perf_tool *tool __maybe_unused)
{
	struct s390_cpumsf *sf = container_of(session->auxtrace,
					      struct s390_cpumsf,
					      auxtrace);

	int fd = perf_data__fd(session->data);
	struct auxtrace_buffer *buffer;
	off_t data_offset;
	int err;

	if (sf->data_queued)
		return 0;

	if (perf_data__is_pipe(session->data)) {
		data_offset = 0;
	} else {
		data_offset = lseek(fd, 0, SEEK_CUR);
		if (data_offset == -1)
			return -errno;
	}

	err = auxtrace_queues__add_event(&sf->queues, session, event,
					 data_offset, &buffer);
	if (err)
		return err;

	/* Dump here after copying piped trace out of the pipe */
	if (dump_trace) {
		if (auxtrace_buffer__get_data(buffer, fd)) {
			s390_cpumsf_dump_event(sf, buffer->data,
					       buffer->size);
			auxtrace_buffer__put_data(buffer);
		}
	}
	return 0;
}

static void s390_cpumsf_free_events(struct perf_session *session __maybe_unused)
{
}

static int s390_cpumsf_flush(struct perf_session *session __maybe_unused,
			     struct perf_tool *tool __maybe_unused)
{
	return 0;
}

static void s390_cpumsf_free_queues(struct perf_session *session)
{
	struct s390_cpumsf *sf = container_of(session->auxtrace,
					      struct s390_cpumsf,
					      auxtrace);
	struct auxtrace_queues *queues = &sf->queues;
	unsigned int i;

	for (i = 0; i < queues->nr_queues; i++) {
		struct s390_cpumsf_queue *sfq = (struct s390_cpumsf_queue *)
						queues->queue_array[i].priv;

		if (sfq != NULL && sfq->logfile) {
			fclose(sfq->logfile);
			sfq->logfile = NULL;
		}
		zfree(&queues->queue_array[i].priv);
	}
	auxtrace_queues__free(queues);
}

static void s390_cpumsf_free(struct perf_session *session)
{
	struct s390_cpumsf *sf = container_of(session->auxtrace,
					      struct s390_cpumsf,
					      auxtrace);

	auxtrace_heap__free(&sf->heap);
	s390_cpumsf_free_queues(session);
	session->auxtrace = NULL;
	free(sf->logdir);
	free(sf);
}

static int s390_cpumsf_get_type(const char *cpuid)
{
	int ret, family = 0;

	ret = sscanf(cpuid, "%*[^,],%u", &family);
	return (ret == 1) ? family : 0;
}

/* Check itrace options set on perf report command.
 * Return true, if none are set or all options specified can be
 * handled on s390 (currently only option 'd' for logging.
 * Return false otherwise.
 */
static bool check_auxtrace_itrace(struct itrace_synth_opts *itops)
{
	bool ison = false;

	if (!itops || !itops->set)
		return true;
	ison = itops->inject || itops->instructions || itops->branches ||
		itops->transactions || itops->ptwrites ||
		itops->pwr_events || itops->errors ||
		itops->dont_decode || itops->calls || itops->returns ||
		itops->callchain || itops->thread_stack ||
		itops->last_branch;
	if (!ison)
		return true;
	pr_err("Unsupported --itrace options specified\n");
	return false;
}

/* Check for AUXTRACE dump directory if it is needed.
 * On failure print an error message but continue.
 * Return 0 on wrong keyword in config file and 1 otherwise.
 */
static int s390_cpumsf__config(const char *var, const char *value, void *cb)
{
	struct s390_cpumsf *sf = cb;
	struct stat stbuf;
	int rc;

	if (strcmp(var, "auxtrace.dumpdir"))
		return 0;
	sf->logdir = strdup(value);
	if (sf->logdir == NULL) {
		pr_err("Failed to find auxtrace log directory %s,"
		       " continue with current directory...\n", value);
		return 1;
	}
	rc = stat(sf->logdir, &stbuf);
	if (rc == -1 || !S_ISDIR(stbuf.st_mode)) {
		pr_err("Missing auxtrace log directory %s,"
		       " continue with current directory...\n", value);
		free(sf->logdir);
		sf->logdir = NULL;
	}
	return 1;
}

int s390_cpumsf_process_auxtrace_info(union perf_event *event,
				      struct perf_session *session)
{
	struct auxtrace_info_event *auxtrace_info = &event->auxtrace_info;
	struct s390_cpumsf *sf;
	int err;

	if (auxtrace_info->header.size < sizeof(struct auxtrace_info_event))
		return -EINVAL;

	sf = zalloc(sizeof(struct s390_cpumsf));
	if (sf == NULL)
		return -ENOMEM;

	if (!check_auxtrace_itrace(session->itrace_synth_opts)) {
		err = -EINVAL;
		goto err_free;
	}
	sf->use_logfile = session->itrace_synth_opts->log;
	if (sf->use_logfile)
		perf_config(s390_cpumsf__config, sf);

	err = auxtrace_queues__init(&sf->queues);
	if (err)
		goto err_free;

	sf->session = session;
	sf->machine = &session->machines.host; /* No kvm support */
	sf->auxtrace_type = auxtrace_info->type;
	sf->pmu_type = PERF_TYPE_RAW;
	sf->machine_type = s390_cpumsf_get_type(session->evlist->env->cpuid);

	sf->auxtrace.process_event = s390_cpumsf_process_event;
	sf->auxtrace.process_auxtrace_event = s390_cpumsf_process_auxtrace_event;
	sf->auxtrace.flush_events = s390_cpumsf_flush;
	sf->auxtrace.free_events = s390_cpumsf_free_events;
	sf->auxtrace.free = s390_cpumsf_free;
	session->auxtrace = &sf->auxtrace;

	if (dump_trace)
		return 0;

	err = auxtrace_queues__process_index(&sf->queues, session);
	if (err)
		goto err_free_queues;

	if (sf->queues.populated)
		sf->data_queued = true;

	return 0;

err_free_queues:
	auxtrace_queues__free(&sf->queues);
	session->auxtrace = NULL;
err_free:
	free(sf->logdir);
	free(sf);
	return err;
}
OpenPOWER on IntegriCloud