summaryrefslogtreecommitdiff
path: root/tools/perf/util/jitdump.c
blob: eda28d3570bc0deff3fd4237149db54986d204ed (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
// SPDX-License-Identifier: GPL-2.0
#include <sys/sysmacros.h>
#include <sys/types.h>
#include <errno.h>
#include <libgen.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <fcntl.h>
#include <unistd.h>
#include <inttypes.h>
#include <byteswap.h>
#include <sys/stat.h>
#include <sys/mman.h>
#include <linux/stringify.h>

#include "util.h"
#include "event.h"
#include "debug.h"
#include "evlist.h"
#include "symbol.h"
#include <elf.h>

#include "tsc.h"
#include "session.h"
#include "jit.h"
#include "jitdump.h"
#include "genelf.h"
#include "../builtin.h"

#include "sane_ctype.h"

struct jit_buf_desc {
	struct perf_data *output;
	struct perf_session *session;
	struct machine *machine;
	union jr_entry   *entry;
	void             *buf;
	uint64_t	 sample_type;
	size_t           bufsize;
	FILE             *in;
	bool		 needs_bswap; /* handles cross-endianness */
	bool		 use_arch_timestamp;
	void		 *debug_data;
	void		 *unwinding_data;
	uint64_t	 unwinding_size;
	uint64_t	 unwinding_mapped_size;
	uint64_t         eh_frame_hdr_size;
	size_t		 nr_debug_entries;
	uint32_t         code_load_count;
	u64		 bytes_written;
	struct rb_root   code_root;
	char		 dir[PATH_MAX];
};

struct debug_line_info {
	unsigned long vma;
	unsigned int lineno;
	/* The filename format is unspecified, absolute path, relative etc. */
	char const filename[0];
};

struct jit_tool {
	struct perf_tool tool;
	struct perf_data	output;
	struct perf_data	input;
	u64 bytes_written;
};

#define hmax(a, b) ((a) > (b) ? (a) : (b))
#define get_jit_tool(t) (container_of(tool, struct jit_tool, tool))

static int
jit_emit_elf(char *filename,
	     const char *sym,
	     uint64_t code_addr,
	     const void *code,
	     int csize,
	     void *debug,
	     int nr_debug_entries,
	     void *unwinding,
	     uint32_t unwinding_header_size,
	     uint32_t unwinding_size)
{
	int ret, fd;

	if (verbose > 0)
		fprintf(stderr, "write ELF image %s\n", filename);

	fd = open(filename, O_CREAT|O_TRUNC|O_WRONLY, 0644);
	if (fd == -1) {
		pr_warning("cannot create jit ELF %s: %s\n", filename, strerror(errno));
		return -1;
	}

	ret = jit_write_elf(fd, code_addr, sym, (const void *)code, csize, debug, nr_debug_entries,
			    unwinding, unwinding_header_size, unwinding_size);

        close(fd);

        if (ret)
                unlink(filename);

	return ret;
}

static void
jit_close(struct jit_buf_desc *jd)
{
	if (!(jd && jd->in))
		return;
	funlockfile(jd->in);
	fclose(jd->in);
	jd->in = NULL;
}

static int
jit_validate_events(struct perf_session *session)
{
	struct perf_evsel *evsel;

	/*
	 * check that all events use CLOCK_MONOTONIC
	 */
	evlist__for_each_entry(session->evlist, evsel) {
		if (evsel->attr.use_clockid == 0 || evsel->attr.clockid != CLOCK_MONOTONIC)
			return -1;
	}
	return 0;
}

static int
jit_open(struct jit_buf_desc *jd, const char *name)
{
	struct jitheader header;
	struct jr_prefix *prefix;
	ssize_t bs, bsz = 0;
	void *n, *buf = NULL;
	int ret, retval = -1;

	jd->in = fopen(name, "r");
	if (!jd->in)
		return -1;

	bsz = hmax(sizeof(header), sizeof(*prefix));

	buf = malloc(bsz);
	if (!buf)
		goto error;

	/*
	 * protect from writer modifying the file while we are reading it
	 */
	flockfile(jd->in);

	ret = fread(buf, sizeof(header), 1, jd->in);
	if (ret != 1)
		goto error;

	memcpy(&header, buf, sizeof(header));

	if (header.magic != JITHEADER_MAGIC) {
		if (header.magic != JITHEADER_MAGIC_SW)
			goto error;
		jd->needs_bswap = true;
	}

	if (jd->needs_bswap) {
		header.version    = bswap_32(header.version);
		header.total_size = bswap_32(header.total_size);
		header.pid	  = bswap_32(header.pid);
		header.elf_mach   = bswap_32(header.elf_mach);
		header.timestamp  = bswap_64(header.timestamp);
		header.flags      = bswap_64(header.flags);
	}

	jd->use_arch_timestamp = header.flags & JITDUMP_FLAGS_ARCH_TIMESTAMP;

	if (verbose > 2)
		pr_debug("version=%u\nhdr.size=%u\nts=0x%llx\npid=%d\nelf_mach=%d\nuse_arch_timestamp=%d\n",
			header.version,
			header.total_size,
			(unsigned long long)header.timestamp,
			header.pid,
			header.elf_mach,
			jd->use_arch_timestamp);

	if (header.version > JITHEADER_VERSION) {
		pr_err("wrong jitdump version %u, expected " __stringify(JITHEADER_VERSION),
			header.version);
		goto error;
	}

	if (header.flags & JITDUMP_FLAGS_RESERVED) {
		pr_err("jitdump file contains invalid or unsupported flags 0x%llx\n",
		       (unsigned long long)header.flags & JITDUMP_FLAGS_RESERVED);
		goto error;
	}

	if (jd->use_arch_timestamp && !jd->session->time_conv.time_mult) {
		pr_err("jitdump file uses arch timestamps but there is no timestamp conversion\n");
		goto error;
	}

	/*
	 * validate event is using the correct clockid
	 */
	if (!jd->use_arch_timestamp && jit_validate_events(jd->session)) {
		pr_err("error, jitted code must be sampled with perf record -k 1\n");
		goto error;
	}

	bs = header.total_size - sizeof(header);

	if (bs > bsz) {
		n = realloc(buf, bs);
		if (!n)
			goto error;
		bsz = bs;
		buf = n;
		/* read extra we do not know about */
		ret = fread(buf, bs - bsz, 1, jd->in);
		if (ret != 1)
			goto error;
	}
	/*
	 * keep dirname for generating files and mmap records
	 */
	strcpy(jd->dir, name);
	dirname(jd->dir);

	return 0;
error:
	funlockfile(jd->in);
	fclose(jd->in);
	return retval;
}

static union jr_entry *
jit_get_next_entry(struct jit_buf_desc *jd)
{
	struct jr_prefix *prefix;
	union jr_entry *jr;
	void *addr;
	size_t bs, size;
	int id, ret;

	if (!(jd && jd->in))
		return NULL;

	if (jd->buf == NULL) {
		size_t sz = getpagesize();
		if (sz < sizeof(*prefix))
			sz = sizeof(*prefix);

		jd->buf = malloc(sz);
		if (jd->buf == NULL)
			return NULL;

		jd->bufsize = sz;
	}

	prefix = jd->buf;

	/*
	 * file is still locked at this point
	 */
	ret = fread(prefix, sizeof(*prefix), 1, jd->in);
	if (ret  != 1)
		return NULL;

	if (jd->needs_bswap) {
		prefix->id   	   = bswap_32(prefix->id);
		prefix->total_size = bswap_32(prefix->total_size);
		prefix->timestamp  = bswap_64(prefix->timestamp);
	}
	id   = prefix->id;
	size = prefix->total_size;

	bs = (size_t)size;
	if (bs < sizeof(*prefix))
		return NULL;

	if (id >= JIT_CODE_MAX) {
		pr_warning("next_entry: unknown record type %d, skipping\n", id);
	}
	if (bs > jd->bufsize) {
		void *n;
		n = realloc(jd->buf, bs);
		if (!n)
			return NULL;
		jd->buf = n;
		jd->bufsize = bs;
	}

	addr = ((void *)jd->buf) + sizeof(*prefix);

	ret = fread(addr, bs - sizeof(*prefix), 1, jd->in);
	if (ret != 1)
		return NULL;

	jr = (union jr_entry *)jd->buf;

	switch(id) {
	case JIT_CODE_DEBUG_INFO:
		if (jd->needs_bswap) {
			uint64_t n;
			jr->info.code_addr = bswap_64(jr->info.code_addr);
			jr->info.nr_entry  = bswap_64(jr->info.nr_entry);
			for (n = 0 ; n < jr->info.nr_entry; n++) {
				jr->info.entries[n].addr    = bswap_64(jr->info.entries[n].addr);
				jr->info.entries[n].lineno  = bswap_32(jr->info.entries[n].lineno);
				jr->info.entries[n].discrim = bswap_32(jr->info.entries[n].discrim);
			}
		}
		break;
	case JIT_CODE_UNWINDING_INFO:
		if (jd->needs_bswap) {
			jr->unwinding.unwinding_size = bswap_64(jr->unwinding.unwinding_size);
			jr->unwinding.eh_frame_hdr_size = bswap_64(jr->unwinding.eh_frame_hdr_size);
			jr->unwinding.mapped_size = bswap_64(jr->unwinding.mapped_size);
		}
		break;
	case JIT_CODE_CLOSE:
		break;
	case JIT_CODE_LOAD:
		if (jd->needs_bswap) {
			jr->load.pid       = bswap_32(jr->load.pid);
			jr->load.tid       = bswap_32(jr->load.tid);
			jr->load.vma       = bswap_64(jr->load.vma);
			jr->load.code_addr = bswap_64(jr->load.code_addr);
			jr->load.code_size = bswap_64(jr->load.code_size);
			jr->load.code_index= bswap_64(jr->load.code_index);
		}
		jd->code_load_count++;
		break;
	case JIT_CODE_MOVE:
		if (jd->needs_bswap) {
			jr->move.pid           = bswap_32(jr->move.pid);
			jr->move.tid           = bswap_32(jr->move.tid);
			jr->move.vma           = bswap_64(jr->move.vma);
			jr->move.old_code_addr = bswap_64(jr->move.old_code_addr);
			jr->move.new_code_addr = bswap_64(jr->move.new_code_addr);
			jr->move.code_size     = bswap_64(jr->move.code_size);
			jr->move.code_index    = bswap_64(jr->move.code_index);
		}
		break;
	case JIT_CODE_MAX:
	default:
		/* skip unknown record (we have read them) */
		break;
	}
	return jr;
}

static int
jit_inject_event(struct jit_buf_desc *jd, union perf_event *event)
{
	ssize_t size;

	size = perf_data__write(jd->output, event, event->header.size);
	if (size < 0)
		return -1;

	jd->bytes_written += size;
	return 0;
}

static uint64_t convert_timestamp(struct jit_buf_desc *jd, uint64_t timestamp)
{
	struct perf_tsc_conversion tc;

	if (!jd->use_arch_timestamp)
		return timestamp;

	tc.time_shift = jd->session->time_conv.time_shift;
	tc.time_mult  = jd->session->time_conv.time_mult;
	tc.time_zero  = jd->session->time_conv.time_zero;

	if (!tc.time_mult)
		return 0;

	return tsc_to_perf_time(timestamp, &tc);
}

static int jit_repipe_code_load(struct jit_buf_desc *jd, union jr_entry *jr)
{
	struct perf_sample sample;
	union perf_event *event;
	struct perf_tool *tool = jd->session->tool;
	uint64_t code, addr;
	uintptr_t uaddr;
	char *filename;
	struct stat st;
	size_t size;
	u16 idr_size;
	const char *sym;
	uint32_t count;
	int ret, csize, usize;
	pid_t pid, tid;
	struct {
		u32 pid, tid;
		u64 time;
	} *id;

	pid   = jr->load.pid;
	tid   = jr->load.tid;
	csize = jr->load.code_size;
	usize = jd->unwinding_mapped_size;
	addr  = jr->load.code_addr;
	sym   = (void *)((unsigned long)jr + sizeof(jr->load));
	code  = (unsigned long)jr + jr->load.p.total_size - csize;
	count = jr->load.code_index;
	idr_size = jd->machine->id_hdr_size;

	event = calloc(1, sizeof(*event) + idr_size);
	if (!event)
		return -1;

	filename = event->mmap2.filename;
	size = snprintf(filename, PATH_MAX, "%s/jitted-%d-%u.so",
			jd->dir,
			pid,
			count);

	size++; /* for \0 */

	size = PERF_ALIGN(size, sizeof(u64));
	uaddr = (uintptr_t)code;
	ret = jit_emit_elf(filename, sym, addr, (const void *)uaddr, csize, jd->debug_data, jd->nr_debug_entries,
			   jd->unwinding_data, jd->eh_frame_hdr_size, jd->unwinding_size);

	if (jd->debug_data && jd->nr_debug_entries) {
		free(jd->debug_data);
		jd->debug_data = NULL;
		jd->nr_debug_entries = 0;
	}

	if (jd->unwinding_data && jd->eh_frame_hdr_size) {
		free(jd->unwinding_data);
		jd->unwinding_data = NULL;
		jd->eh_frame_hdr_size = 0;
		jd->unwinding_mapped_size = 0;
		jd->unwinding_size = 0;
	}

	if (ret) {
		free(event);
		return -1;
	}
	if (stat(filename, &st))
		memset(&st, 0, sizeof(st));

	event->mmap2.header.type = PERF_RECORD_MMAP2;
	event->mmap2.header.misc = PERF_RECORD_MISC_USER;
	event->mmap2.header.size = (sizeof(event->mmap2) -
			(sizeof(event->mmap2.filename) - size) + idr_size);

	event->mmap2.pgoff = GEN_ELF_TEXT_OFFSET;
	event->mmap2.start = addr;
	event->mmap2.len   = usize ? ALIGN_8(csize) + usize : csize;
	event->mmap2.pid   = pid;
	event->mmap2.tid   = tid;
	event->mmap2.ino   = st.st_ino;
	event->mmap2.maj   = major(st.st_dev);
	event->mmap2.min   = minor(st.st_dev);
	event->mmap2.prot  = st.st_mode;
	event->mmap2.flags = MAP_SHARED;
	event->mmap2.ino_generation = 1;

	id = (void *)((unsigned long)event + event->mmap.header.size - idr_size);
	if (jd->sample_type & PERF_SAMPLE_TID) {
		id->pid  = pid;
		id->tid  = tid;
	}
	if (jd->sample_type & PERF_SAMPLE_TIME)
		id->time = convert_timestamp(jd, jr->load.p.timestamp);

	/*
	 * create pseudo sample to induce dso hit increment
	 * use first address as sample address
	 */
	memset(&sample, 0, sizeof(sample));
	sample.cpumode = PERF_RECORD_MISC_USER;
	sample.pid  = pid;
	sample.tid  = tid;
	sample.time = id->time;
	sample.ip   = addr;

	ret = perf_event__process_mmap2(tool, event, &sample, jd->machine);
	if (ret)
		return ret;

	ret = jit_inject_event(jd, event);
	/*
	 * mark dso as use to generate buildid in the header
	 */
	if (!ret)
		build_id__mark_dso_hit(tool, event, &sample, NULL, jd->machine);

	return ret;
}

static int jit_repipe_code_move(struct jit_buf_desc *jd, union jr_entry *jr)
{
	struct perf_sample sample;
	union perf_event *event;
	struct perf_tool *tool = jd->session->tool;
	char *filename;
	size_t size;
	struct stat st;
	int usize;
	u16 idr_size;
	int ret;
	pid_t pid, tid;
	struct {
		u32 pid, tid;
		u64 time;
	} *id;

	pid = jr->move.pid;
	tid =  jr->move.tid;
	usize = jd->unwinding_mapped_size;
	idr_size = jd->machine->id_hdr_size;

	/*
	 * +16 to account for sample_id_all (hack)
	 */
	event = calloc(1, sizeof(*event) + 16);
	if (!event)
		return -1;

	filename = event->mmap2.filename;
	size = snprintf(filename, PATH_MAX, "%s/jitted-%d-%"PRIu64,
	         jd->dir,
	         pid,
		 jr->move.code_index);

	size++; /* for \0 */

	if (stat(filename, &st))
		memset(&st, 0, sizeof(st));

	size = PERF_ALIGN(size, sizeof(u64));

	event->mmap2.header.type = PERF_RECORD_MMAP2;
	event->mmap2.header.misc = PERF_RECORD_MISC_USER;
	event->mmap2.header.size = (sizeof(event->mmap2) -
			(sizeof(event->mmap2.filename) - size) + idr_size);
	event->mmap2.pgoff = GEN_ELF_TEXT_OFFSET;
	event->mmap2.start = jr->move.new_code_addr;
	event->mmap2.len   = usize ? ALIGN_8(jr->move.code_size) + usize
				   : jr->move.code_size;
	event->mmap2.pid   = pid;
	event->mmap2.tid   = tid;
	event->mmap2.ino   = st.st_ino;
	event->mmap2.maj   = major(st.st_dev);
	event->mmap2.min   = minor(st.st_dev);
	event->mmap2.prot  = st.st_mode;
	event->mmap2.flags = MAP_SHARED;
	event->mmap2.ino_generation = 1;

	id = (void *)((unsigned long)event + event->mmap.header.size - idr_size);
	if (jd->sample_type & PERF_SAMPLE_TID) {
		id->pid  = pid;
		id->tid  = tid;
	}
	if (jd->sample_type & PERF_SAMPLE_TIME)
		id->time = convert_timestamp(jd, jr->load.p.timestamp);

	/*
	 * create pseudo sample to induce dso hit increment
	 * use first address as sample address
	 */
	memset(&sample, 0, sizeof(sample));
	sample.cpumode = PERF_RECORD_MISC_USER;
	sample.pid  = pid;
	sample.tid  = tid;
	sample.time = id->time;
	sample.ip   = jr->move.new_code_addr;

	ret = perf_event__process_mmap2(tool, event, &sample, jd->machine);
	if (ret)
		return ret;

	ret = jit_inject_event(jd, event);
	if (!ret)
		build_id__mark_dso_hit(tool, event, &sample, NULL, jd->machine);

	return ret;
}

static int jit_repipe_debug_info(struct jit_buf_desc *jd, union jr_entry *jr)
{
	void *data;
	size_t sz;

	if (!(jd && jr))
		return -1;

	sz  = jr->prefix.total_size - sizeof(jr->info);
	data = malloc(sz);
	if (!data)
		return -1;

	memcpy(data, &jr->info.entries, sz);

	jd->debug_data       = data;

	/*
	 * we must use nr_entry instead of size here because
	 * we cannot distinguish actual entry from padding otherwise
	 */
	jd->nr_debug_entries = jr->info.nr_entry;

	return 0;
}

static int
jit_repipe_unwinding_info(struct jit_buf_desc *jd, union jr_entry *jr)
{
	void *unwinding_data;
	uint32_t unwinding_data_size;

	if (!(jd && jr))
		return -1;

	unwinding_data_size  = jr->prefix.total_size - sizeof(jr->unwinding);
	unwinding_data = malloc(unwinding_data_size);
	if (!unwinding_data)
		return -1;

	memcpy(unwinding_data, &jr->unwinding.unwinding_data,
	       unwinding_data_size);

	jd->eh_frame_hdr_size = jr->unwinding.eh_frame_hdr_size;
	jd->unwinding_size = jr->unwinding.unwinding_size;
	jd->unwinding_mapped_size = jr->unwinding.mapped_size;
	jd->unwinding_data = unwinding_data;

	return 0;
}

static int
jit_process_dump(struct jit_buf_desc *jd)
{
	union jr_entry *jr;
	int ret = 0;

	while ((jr = jit_get_next_entry(jd))) {
		switch(jr->prefix.id) {
		case JIT_CODE_LOAD:
			ret = jit_repipe_code_load(jd, jr);
			break;
		case JIT_CODE_MOVE:
			ret = jit_repipe_code_move(jd, jr);
			break;
		case JIT_CODE_DEBUG_INFO:
			ret = jit_repipe_debug_info(jd, jr);
			break;
		case JIT_CODE_UNWINDING_INFO:
			ret = jit_repipe_unwinding_info(jd, jr);
			break;
		default:
			ret = 0;
			continue;
		}
	}
	return ret;
}

static int
jit_inject(struct jit_buf_desc *jd, char *path)
{
	int ret;

	if (verbose > 0)
		fprintf(stderr, "injecting: %s\n", path);

	ret = jit_open(jd, path);
	if (ret)
		return -1;

	ret = jit_process_dump(jd);

	jit_close(jd);

	if (verbose > 0)
		fprintf(stderr, "injected: %s (%d)\n", path, ret);

	return 0;
}

/*
 * File must be with pattern .../jit-XXXX.dump
 * where XXXX is the PID of the process which did the mmap()
 * as captured in the RECORD_MMAP record
 */
static int
jit_detect(char *mmap_name, pid_t pid)
 {
	char *p;
	char *end = NULL;
	pid_t pid2;

	if (verbose > 2)
		fprintf(stderr, "jit marker trying : %s\n", mmap_name);
	/*
	 * get file name
	 */
	p = strrchr(mmap_name, '/');
	if (!p)
		return -1;

	/*
	 * match prefix
	 */
	if (strncmp(p, "/jit-", 5))
		return -1;

	/*
	 * skip prefix
	 */
	p += 5;

	/*
	 * must be followed by a pid
	 */
	if (!isdigit(*p))
		return -1;

	pid2 = (int)strtol(p, &end, 10);
	if (!end)
		return -1;

	/*
	 * pid does not match mmap pid
	 * pid==0 in system-wide mode (synthesized)
	 */
	if (pid && pid2 != pid)
		return -1;
	/*
	 * validate suffix
	 */
	if (strcmp(end, ".dump"))
		return -1;

	if (verbose > 0)
		fprintf(stderr, "jit marker found: %s\n", mmap_name);

	return 0;
}

int
jit_process(struct perf_session *session,
	    struct perf_data *output,
	    struct machine *machine,
	    char *filename,
	    pid_t pid,
	    u64 *nbytes)
{
	struct perf_evsel *first;
	struct jit_buf_desc jd;
	int ret;

	/*
	 * first, detect marker mmap (i.e., the jitdump mmap)
	 */
	if (jit_detect(filename, pid))
		return 0;

	memset(&jd, 0, sizeof(jd));

	jd.session = session;
	jd.output  = output;
	jd.machine = machine;

	/*
	 * track sample_type to compute id_all layout
	 * perf sets the same sample type to all events as of now
	 */
	first = perf_evlist__first(session->evlist);
	jd.sample_type = first->attr.sample_type;

	*nbytes = 0;

	ret = jit_inject(&jd, filename);
	if (!ret) {
		*nbytes = jd.bytes_written;
		ret = 1;
	}

	return ret;
}