xref: /openbmc/linux/tools/perf/util/jitdump.c (revision 11a163f2)
1 // SPDX-License-Identifier: GPL-2.0
2 #include <sys/sysmacros.h>
3 #include <sys/types.h>
4 #include <errno.h>
5 #include <libgen.h>
6 #include <stdio.h>
7 #include <stdlib.h>
8 #include <string.h>
9 #include <fcntl.h>
10 #include <unistd.h>
11 #include <inttypes.h>
12 #include <byteswap.h>
13 #include <sys/stat.h>
14 #include <sys/mman.h>
15 #include <linux/stringify.h>
16 
17 #include "build-id.h"
18 #include "event.h"
19 #include "debug.h"
20 #include "evlist.h"
21 #include "symbol.h"
22 #include <elf.h>
23 
24 #include "tsc.h"
25 #include "session.h"
26 #include "jit.h"
27 #include "jitdump.h"
28 #include "genelf.h"
29 #include "thread.h"
30 
31 #include <linux/ctype.h>
32 #include <linux/zalloc.h>
33 
34 struct jit_buf_desc {
35 	struct perf_data *output;
36 	struct perf_session *session;
37 	struct machine *machine;
38 	union jr_entry   *entry;
39 	void             *buf;
40 	uint64_t	 sample_type;
41 	size_t           bufsize;
42 	FILE             *in;
43 	bool		 needs_bswap; /* handles cross-endianness */
44 	bool		 use_arch_timestamp;
45 	void		 *debug_data;
46 	void		 *unwinding_data;
47 	uint64_t	 unwinding_size;
48 	uint64_t	 unwinding_mapped_size;
49 	uint64_t         eh_frame_hdr_size;
50 	size_t		 nr_debug_entries;
51 	uint32_t         code_load_count;
52 	u64		 bytes_written;
53 	struct rb_root   code_root;
54 	char		 dir[PATH_MAX];
55 };
56 
57 struct debug_line_info {
58 	unsigned long vma;
59 	unsigned int lineno;
60 	/* The filename format is unspecified, absolute path, relative etc. */
61 	char const filename[];
62 };
63 
64 struct jit_tool {
65 	struct perf_tool tool;
66 	struct perf_data	output;
67 	struct perf_data	input;
68 	u64 bytes_written;
69 };
70 
71 #define hmax(a, b) ((a) > (b) ? (a) : (b))
72 #define get_jit_tool(t) (container_of(tool, struct jit_tool, tool))
73 
74 static int
75 jit_emit_elf(char *filename,
76 	     const char *sym,
77 	     uint64_t code_addr,
78 	     const void *code,
79 	     int csize,
80 	     void *debug,
81 	     int nr_debug_entries,
82 	     void *unwinding,
83 	     uint32_t unwinding_header_size,
84 	     uint32_t unwinding_size)
85 {
86 	int ret, fd;
87 
88 	if (verbose > 0)
89 		fprintf(stderr, "write ELF image %s\n", filename);
90 
91 	fd = open(filename, O_CREAT|O_TRUNC|O_WRONLY, 0644);
92 	if (fd == -1) {
93 		pr_warning("cannot create jit ELF %s: %s\n", filename, strerror(errno));
94 		return -1;
95 	}
96 
97 	ret = jit_write_elf(fd, code_addr, sym, (const void *)code, csize, debug, nr_debug_entries,
98 			    unwinding, unwinding_header_size, unwinding_size);
99 
100         close(fd);
101 
102         if (ret)
103                 unlink(filename);
104 
105 	return ret;
106 }
107 
108 static void
109 jit_close(struct jit_buf_desc *jd)
110 {
111 	if (!(jd && jd->in))
112 		return;
113 	funlockfile(jd->in);
114 	fclose(jd->in);
115 	jd->in = NULL;
116 }
117 
118 static int
119 jit_validate_events(struct perf_session *session)
120 {
121 	struct evsel *evsel;
122 
123 	/*
124 	 * check that all events use CLOCK_MONOTONIC
125 	 */
126 	evlist__for_each_entry(session->evlist, evsel) {
127 		if (evsel->core.attr.use_clockid == 0 || evsel->core.attr.clockid != CLOCK_MONOTONIC)
128 			return -1;
129 	}
130 	return 0;
131 }
132 
133 static int
134 jit_open(struct jit_buf_desc *jd, const char *name)
135 {
136 	struct jitheader header;
137 	struct jr_prefix *prefix;
138 	ssize_t bs, bsz = 0;
139 	void *n, *buf = NULL;
140 	int ret, retval = -1;
141 
142 	jd->in = fopen(name, "r");
143 	if (!jd->in)
144 		return -1;
145 
146 	bsz = hmax(sizeof(header), sizeof(*prefix));
147 
148 	buf = malloc(bsz);
149 	if (!buf)
150 		goto error;
151 
152 	/*
153 	 * protect from writer modifying the file while we are reading it
154 	 */
155 	flockfile(jd->in);
156 
157 	ret = fread(buf, sizeof(header), 1, jd->in);
158 	if (ret != 1)
159 		goto error;
160 
161 	memcpy(&header, buf, sizeof(header));
162 
163 	if (header.magic != JITHEADER_MAGIC) {
164 		if (header.magic != JITHEADER_MAGIC_SW)
165 			goto error;
166 		jd->needs_bswap = true;
167 	}
168 
169 	if (jd->needs_bswap) {
170 		header.version    = bswap_32(header.version);
171 		header.total_size = bswap_32(header.total_size);
172 		header.pid	  = bswap_32(header.pid);
173 		header.elf_mach   = bswap_32(header.elf_mach);
174 		header.timestamp  = bswap_64(header.timestamp);
175 		header.flags      = bswap_64(header.flags);
176 	}
177 
178 	jd->use_arch_timestamp = header.flags & JITDUMP_FLAGS_ARCH_TIMESTAMP;
179 
180 	if (verbose > 2)
181 		pr_debug("version=%u\nhdr.size=%u\nts=0x%llx\npid=%d\nelf_mach=%d\nuse_arch_timestamp=%d\n",
182 			header.version,
183 			header.total_size,
184 			(unsigned long long)header.timestamp,
185 			header.pid,
186 			header.elf_mach,
187 			jd->use_arch_timestamp);
188 
189 	if (header.version > JITHEADER_VERSION) {
190 		pr_err("wrong jitdump version %u, expected " __stringify(JITHEADER_VERSION),
191 			header.version);
192 		goto error;
193 	}
194 
195 	if (header.flags & JITDUMP_FLAGS_RESERVED) {
196 		pr_err("jitdump file contains invalid or unsupported flags 0x%llx\n",
197 		       (unsigned long long)header.flags & JITDUMP_FLAGS_RESERVED);
198 		goto error;
199 	}
200 
201 	if (jd->use_arch_timestamp && !jd->session->time_conv.time_mult) {
202 		pr_err("jitdump file uses arch timestamps but there is no timestamp conversion\n");
203 		goto error;
204 	}
205 
206 	/*
207 	 * validate event is using the correct clockid
208 	 */
209 	if (!jd->use_arch_timestamp && jit_validate_events(jd->session)) {
210 		pr_err("error, jitted code must be sampled with perf record -k 1\n");
211 		goto error;
212 	}
213 
214 	bs = header.total_size - sizeof(header);
215 
216 	if (bs > bsz) {
217 		n = realloc(buf, bs);
218 		if (!n)
219 			goto error;
220 		bsz = bs;
221 		buf = n;
222 		/* read extra we do not know about */
223 		ret = fread(buf, bs - bsz, 1, jd->in);
224 		if (ret != 1)
225 			goto error;
226 	}
227 	/*
228 	 * keep dirname for generating files and mmap records
229 	 */
230 	strcpy(jd->dir, name);
231 	dirname(jd->dir);
232 
233 	return 0;
234 error:
235 	funlockfile(jd->in);
236 	fclose(jd->in);
237 	return retval;
238 }
239 
240 static union jr_entry *
241 jit_get_next_entry(struct jit_buf_desc *jd)
242 {
243 	struct jr_prefix *prefix;
244 	union jr_entry *jr;
245 	void *addr;
246 	size_t bs, size;
247 	int id, ret;
248 
249 	if (!(jd && jd->in))
250 		return NULL;
251 
252 	if (jd->buf == NULL) {
253 		size_t sz = getpagesize();
254 		if (sz < sizeof(*prefix))
255 			sz = sizeof(*prefix);
256 
257 		jd->buf = malloc(sz);
258 		if (jd->buf == NULL)
259 			return NULL;
260 
261 		jd->bufsize = sz;
262 	}
263 
264 	prefix = jd->buf;
265 
266 	/*
267 	 * file is still locked at this point
268 	 */
269 	ret = fread(prefix, sizeof(*prefix), 1, jd->in);
270 	if (ret  != 1)
271 		return NULL;
272 
273 	if (jd->needs_bswap) {
274 		prefix->id   	   = bswap_32(prefix->id);
275 		prefix->total_size = bswap_32(prefix->total_size);
276 		prefix->timestamp  = bswap_64(prefix->timestamp);
277 	}
278 	id   = prefix->id;
279 	size = prefix->total_size;
280 
281 	bs = (size_t)size;
282 	if (bs < sizeof(*prefix))
283 		return NULL;
284 
285 	if (id >= JIT_CODE_MAX) {
286 		pr_warning("next_entry: unknown record type %d, skipping\n", id);
287 	}
288 	if (bs > jd->bufsize) {
289 		void *n;
290 		n = realloc(jd->buf, bs);
291 		if (!n)
292 			return NULL;
293 		jd->buf = n;
294 		jd->bufsize = bs;
295 	}
296 
297 	addr = ((void *)jd->buf) + sizeof(*prefix);
298 
299 	ret = fread(addr, bs - sizeof(*prefix), 1, jd->in);
300 	if (ret != 1)
301 		return NULL;
302 
303 	jr = (union jr_entry *)jd->buf;
304 
305 	switch(id) {
306 	case JIT_CODE_DEBUG_INFO:
307 		if (jd->needs_bswap) {
308 			uint64_t n;
309 			jr->info.code_addr = bswap_64(jr->info.code_addr);
310 			jr->info.nr_entry  = bswap_64(jr->info.nr_entry);
311 			for (n = 0 ; n < jr->info.nr_entry; n++) {
312 				jr->info.entries[n].addr    = bswap_64(jr->info.entries[n].addr);
313 				jr->info.entries[n].lineno  = bswap_32(jr->info.entries[n].lineno);
314 				jr->info.entries[n].discrim = bswap_32(jr->info.entries[n].discrim);
315 			}
316 		}
317 		break;
318 	case JIT_CODE_UNWINDING_INFO:
319 		if (jd->needs_bswap) {
320 			jr->unwinding.unwinding_size = bswap_64(jr->unwinding.unwinding_size);
321 			jr->unwinding.eh_frame_hdr_size = bswap_64(jr->unwinding.eh_frame_hdr_size);
322 			jr->unwinding.mapped_size = bswap_64(jr->unwinding.mapped_size);
323 		}
324 		break;
325 	case JIT_CODE_CLOSE:
326 		break;
327 	case JIT_CODE_LOAD:
328 		if (jd->needs_bswap) {
329 			jr->load.pid       = bswap_32(jr->load.pid);
330 			jr->load.tid       = bswap_32(jr->load.tid);
331 			jr->load.vma       = bswap_64(jr->load.vma);
332 			jr->load.code_addr = bswap_64(jr->load.code_addr);
333 			jr->load.code_size = bswap_64(jr->load.code_size);
334 			jr->load.code_index= bswap_64(jr->load.code_index);
335 		}
336 		jd->code_load_count++;
337 		break;
338 	case JIT_CODE_MOVE:
339 		if (jd->needs_bswap) {
340 			jr->move.pid           = bswap_32(jr->move.pid);
341 			jr->move.tid           = bswap_32(jr->move.tid);
342 			jr->move.vma           = bswap_64(jr->move.vma);
343 			jr->move.old_code_addr = bswap_64(jr->move.old_code_addr);
344 			jr->move.new_code_addr = bswap_64(jr->move.new_code_addr);
345 			jr->move.code_size     = bswap_64(jr->move.code_size);
346 			jr->move.code_index    = bswap_64(jr->move.code_index);
347 		}
348 		break;
349 	case JIT_CODE_MAX:
350 	default:
351 		/* skip unknown record (we have read them) */
352 		break;
353 	}
354 	return jr;
355 }
356 
357 static int
358 jit_inject_event(struct jit_buf_desc *jd, union perf_event *event)
359 {
360 	ssize_t size;
361 
362 	size = perf_data__write(jd->output, event, event->header.size);
363 	if (size < 0)
364 		return -1;
365 
366 	jd->bytes_written += size;
367 	return 0;
368 }
369 
370 static uint64_t convert_timestamp(struct jit_buf_desc *jd, uint64_t timestamp)
371 {
372 	struct perf_tsc_conversion tc;
373 
374 	if (!jd->use_arch_timestamp)
375 		return timestamp;
376 
377 	tc.time_shift	       = jd->session->time_conv.time_shift;
378 	tc.time_mult	       = jd->session->time_conv.time_mult;
379 	tc.time_zero	       = jd->session->time_conv.time_zero;
380 	tc.time_cycles	       = jd->session->time_conv.time_cycles;
381 	tc.time_mask	       = jd->session->time_conv.time_mask;
382 	tc.cap_user_time_zero  = jd->session->time_conv.cap_user_time_zero;
383 	tc.cap_user_time_short = jd->session->time_conv.cap_user_time_short;
384 
385 	if (!tc.cap_user_time_zero)
386 		return 0;
387 
388 	return tsc_to_perf_time(timestamp, &tc);
389 }
390 
391 static int jit_repipe_code_load(struct jit_buf_desc *jd, union jr_entry *jr)
392 {
393 	struct perf_sample sample;
394 	union perf_event *event;
395 	struct perf_tool *tool = jd->session->tool;
396 	uint64_t code, addr;
397 	uintptr_t uaddr;
398 	char *filename;
399 	struct stat st;
400 	size_t size;
401 	u16 idr_size;
402 	const char *sym;
403 	uint64_t count;
404 	int ret, csize, usize;
405 	pid_t pid, tid;
406 	struct {
407 		u32 pid, tid;
408 		u64 time;
409 	} *id;
410 
411 	pid   = jr->load.pid;
412 	tid   = jr->load.tid;
413 	csize = jr->load.code_size;
414 	usize = jd->unwinding_mapped_size;
415 	addr  = jr->load.code_addr;
416 	sym   = (void *)((unsigned long)jr + sizeof(jr->load));
417 	code  = (unsigned long)jr + jr->load.p.total_size - csize;
418 	count = jr->load.code_index;
419 	idr_size = jd->machine->id_hdr_size;
420 
421 	event = calloc(1, sizeof(*event) + idr_size);
422 	if (!event)
423 		return -1;
424 
425 	filename = event->mmap2.filename;
426 	size = snprintf(filename, PATH_MAX, "%s/jitted-%d-%" PRIu64 ".so",
427 			jd->dir,
428 			pid,
429 			count);
430 
431 	size++; /* for \0 */
432 
433 	size = PERF_ALIGN(size, sizeof(u64));
434 	uaddr = (uintptr_t)code;
435 	ret = jit_emit_elf(filename, sym, addr, (const void *)uaddr, csize, jd->debug_data, jd->nr_debug_entries,
436 			   jd->unwinding_data, jd->eh_frame_hdr_size, jd->unwinding_size);
437 
438 	if (jd->debug_data && jd->nr_debug_entries) {
439 		zfree(&jd->debug_data);
440 		jd->nr_debug_entries = 0;
441 	}
442 
443 	if (jd->unwinding_data && jd->eh_frame_hdr_size) {
444 		zfree(&jd->unwinding_data);
445 		jd->eh_frame_hdr_size = 0;
446 		jd->unwinding_mapped_size = 0;
447 		jd->unwinding_size = 0;
448 	}
449 
450 	if (ret) {
451 		free(event);
452 		return -1;
453 	}
454 	if (stat(filename, &st))
455 		memset(&st, 0, sizeof(st));
456 
457 	event->mmap2.header.type = PERF_RECORD_MMAP2;
458 	event->mmap2.header.misc = PERF_RECORD_MISC_USER;
459 	event->mmap2.header.size = (sizeof(event->mmap2) -
460 			(sizeof(event->mmap2.filename) - size) + idr_size);
461 
462 	event->mmap2.pgoff = GEN_ELF_TEXT_OFFSET;
463 	event->mmap2.start = addr;
464 	event->mmap2.len   = usize ? ALIGN_8(csize) + usize : csize;
465 	event->mmap2.pid   = pid;
466 	event->mmap2.tid   = tid;
467 	event->mmap2.ino   = st.st_ino;
468 	event->mmap2.maj   = major(st.st_dev);
469 	event->mmap2.min   = minor(st.st_dev);
470 	event->mmap2.prot  = st.st_mode;
471 	event->mmap2.flags = MAP_SHARED;
472 	event->mmap2.ino_generation = 1;
473 
474 	id = (void *)((unsigned long)event + event->mmap.header.size - idr_size);
475 	if (jd->sample_type & PERF_SAMPLE_TID) {
476 		id->pid  = pid;
477 		id->tid  = tid;
478 	}
479 	if (jd->sample_type & PERF_SAMPLE_TIME)
480 		id->time = convert_timestamp(jd, jr->load.p.timestamp);
481 
482 	/*
483 	 * create pseudo sample to induce dso hit increment
484 	 * use first address as sample address
485 	 */
486 	memset(&sample, 0, sizeof(sample));
487 	sample.cpumode = PERF_RECORD_MISC_USER;
488 	sample.pid  = pid;
489 	sample.tid  = tid;
490 	sample.time = id->time;
491 	sample.ip   = addr;
492 
493 	ret = perf_event__process_mmap2(tool, event, &sample, jd->machine);
494 	if (ret)
495 		return ret;
496 
497 	ret = jit_inject_event(jd, event);
498 	/*
499 	 * mark dso as use to generate buildid in the header
500 	 */
501 	if (!ret)
502 		build_id__mark_dso_hit(tool, event, &sample, NULL, jd->machine);
503 
504 	return ret;
505 }
506 
507 static int jit_repipe_code_move(struct jit_buf_desc *jd, union jr_entry *jr)
508 {
509 	struct perf_sample sample;
510 	union perf_event *event;
511 	struct perf_tool *tool = jd->session->tool;
512 	char *filename;
513 	size_t size;
514 	struct stat st;
515 	int usize;
516 	u16 idr_size;
517 	int ret;
518 	pid_t pid, tid;
519 	struct {
520 		u32 pid, tid;
521 		u64 time;
522 	} *id;
523 
524 	pid = jr->move.pid;
525 	tid =  jr->move.tid;
526 	usize = jd->unwinding_mapped_size;
527 	idr_size = jd->machine->id_hdr_size;
528 
529 	/*
530 	 * +16 to account for sample_id_all (hack)
531 	 */
532 	event = calloc(1, sizeof(*event) + 16);
533 	if (!event)
534 		return -1;
535 
536 	filename = event->mmap2.filename;
537 	size = snprintf(filename, PATH_MAX, "%s/jitted-%d-%" PRIu64 ".so",
538 	         jd->dir,
539 	         pid,
540 		 jr->move.code_index);
541 
542 	size++; /* for \0 */
543 
544 	if (stat(filename, &st))
545 		memset(&st, 0, sizeof(st));
546 
547 	size = PERF_ALIGN(size, sizeof(u64));
548 
549 	event->mmap2.header.type = PERF_RECORD_MMAP2;
550 	event->mmap2.header.misc = PERF_RECORD_MISC_USER;
551 	event->mmap2.header.size = (sizeof(event->mmap2) -
552 			(sizeof(event->mmap2.filename) - size) + idr_size);
553 	event->mmap2.pgoff = GEN_ELF_TEXT_OFFSET;
554 	event->mmap2.start = jr->move.new_code_addr;
555 	event->mmap2.len   = usize ? ALIGN_8(jr->move.code_size) + usize
556 				   : jr->move.code_size;
557 	event->mmap2.pid   = pid;
558 	event->mmap2.tid   = tid;
559 	event->mmap2.ino   = st.st_ino;
560 	event->mmap2.maj   = major(st.st_dev);
561 	event->mmap2.min   = minor(st.st_dev);
562 	event->mmap2.prot  = st.st_mode;
563 	event->mmap2.flags = MAP_SHARED;
564 	event->mmap2.ino_generation = 1;
565 
566 	id = (void *)((unsigned long)event + event->mmap.header.size - idr_size);
567 	if (jd->sample_type & PERF_SAMPLE_TID) {
568 		id->pid  = pid;
569 		id->tid  = tid;
570 	}
571 	if (jd->sample_type & PERF_SAMPLE_TIME)
572 		id->time = convert_timestamp(jd, jr->load.p.timestamp);
573 
574 	/*
575 	 * create pseudo sample to induce dso hit increment
576 	 * use first address as sample address
577 	 */
578 	memset(&sample, 0, sizeof(sample));
579 	sample.cpumode = PERF_RECORD_MISC_USER;
580 	sample.pid  = pid;
581 	sample.tid  = tid;
582 	sample.time = id->time;
583 	sample.ip   = jr->move.new_code_addr;
584 
585 	ret = perf_event__process_mmap2(tool, event, &sample, jd->machine);
586 	if (ret)
587 		return ret;
588 
589 	ret = jit_inject_event(jd, event);
590 	if (!ret)
591 		build_id__mark_dso_hit(tool, event, &sample, NULL, jd->machine);
592 
593 	return ret;
594 }
595 
596 static int jit_repipe_debug_info(struct jit_buf_desc *jd, union jr_entry *jr)
597 {
598 	void *data;
599 	size_t sz;
600 
601 	if (!(jd && jr))
602 		return -1;
603 
604 	sz  = jr->prefix.total_size - sizeof(jr->info);
605 	data = malloc(sz);
606 	if (!data)
607 		return -1;
608 
609 	memcpy(data, &jr->info.entries, sz);
610 
611 	jd->debug_data       = data;
612 
613 	/*
614 	 * we must use nr_entry instead of size here because
615 	 * we cannot distinguish actual entry from padding otherwise
616 	 */
617 	jd->nr_debug_entries = jr->info.nr_entry;
618 
619 	return 0;
620 }
621 
622 static int
623 jit_repipe_unwinding_info(struct jit_buf_desc *jd, union jr_entry *jr)
624 {
625 	void *unwinding_data;
626 	uint32_t unwinding_data_size;
627 
628 	if (!(jd && jr))
629 		return -1;
630 
631 	unwinding_data_size  = jr->prefix.total_size - sizeof(jr->unwinding);
632 	unwinding_data = malloc(unwinding_data_size);
633 	if (!unwinding_data)
634 		return -1;
635 
636 	memcpy(unwinding_data, &jr->unwinding.unwinding_data,
637 	       unwinding_data_size);
638 
639 	jd->eh_frame_hdr_size = jr->unwinding.eh_frame_hdr_size;
640 	jd->unwinding_size = jr->unwinding.unwinding_size;
641 	jd->unwinding_mapped_size = jr->unwinding.mapped_size;
642 	jd->unwinding_data = unwinding_data;
643 
644 	return 0;
645 }
646 
647 static int
648 jit_process_dump(struct jit_buf_desc *jd)
649 {
650 	union jr_entry *jr;
651 	int ret = 0;
652 
653 	while ((jr = jit_get_next_entry(jd))) {
654 		switch(jr->prefix.id) {
655 		case JIT_CODE_LOAD:
656 			ret = jit_repipe_code_load(jd, jr);
657 			break;
658 		case JIT_CODE_MOVE:
659 			ret = jit_repipe_code_move(jd, jr);
660 			break;
661 		case JIT_CODE_DEBUG_INFO:
662 			ret = jit_repipe_debug_info(jd, jr);
663 			break;
664 		case JIT_CODE_UNWINDING_INFO:
665 			ret = jit_repipe_unwinding_info(jd, jr);
666 			break;
667 		default:
668 			ret = 0;
669 			continue;
670 		}
671 	}
672 	return ret;
673 }
674 
675 static int
676 jit_inject(struct jit_buf_desc *jd, char *path)
677 {
678 	int ret;
679 
680 	if (verbose > 0)
681 		fprintf(stderr, "injecting: %s\n", path);
682 
683 	ret = jit_open(jd, path);
684 	if (ret)
685 		return -1;
686 
687 	ret = jit_process_dump(jd);
688 
689 	jit_close(jd);
690 
691 	if (verbose > 0)
692 		fprintf(stderr, "injected: %s (%d)\n", path, ret);
693 
694 	return 0;
695 }
696 
697 /*
698  * File must be with pattern .../jit-XXXX.dump
699  * where XXXX is the PID of the process which did the mmap()
700  * as captured in the RECORD_MMAP record
701  */
702 static int
703 jit_detect(char *mmap_name, pid_t pid)
704  {
705 	char *p;
706 	char *end = NULL;
707 	pid_t pid2;
708 
709 	if (verbose > 2)
710 		fprintf(stderr, "jit marker trying : %s\n", mmap_name);
711 	/*
712 	 * get file name
713 	 */
714 	p = strrchr(mmap_name, '/');
715 	if (!p)
716 		return -1;
717 
718 	/*
719 	 * match prefix
720 	 */
721 	if (strncmp(p, "/jit-", 5))
722 		return -1;
723 
724 	/*
725 	 * skip prefix
726 	 */
727 	p += 5;
728 
729 	/*
730 	 * must be followed by a pid
731 	 */
732 	if (!isdigit(*p))
733 		return -1;
734 
735 	pid2 = (int)strtol(p, &end, 10);
736 	if (!end)
737 		return -1;
738 
739 	/*
740 	 * pid does not match mmap pid
741 	 * pid==0 in system-wide mode (synthesized)
742 	 */
743 	if (pid && pid2 != pid)
744 		return -1;
745 	/*
746 	 * validate suffix
747 	 */
748 	if (strcmp(end, ".dump"))
749 		return -1;
750 
751 	if (verbose > 0)
752 		fprintf(stderr, "jit marker found: %s\n", mmap_name);
753 
754 	return 0;
755 }
756 
757 static void jit_add_pid(struct machine *machine, pid_t pid)
758 {
759 	struct thread *thread = machine__findnew_thread(machine, pid, pid);
760 
761 	if (!thread) {
762 		pr_err("%s: thread %d not found or created\n", __func__, pid);
763 		return;
764 	}
765 
766 	thread->priv = (void *)1;
767 }
768 
769 static bool jit_has_pid(struct machine *machine, pid_t pid)
770 {
771 	struct thread *thread = machine__find_thread(machine, pid, pid);
772 
773 	if (!thread)
774 		return 0;
775 
776 	return (bool)thread->priv;
777 }
778 
779 int
780 jit_process(struct perf_session *session,
781 	    struct perf_data *output,
782 	    struct machine *machine,
783 	    char *filename,
784 	    pid_t pid,
785 	    u64 *nbytes)
786 {
787 	struct evsel *first;
788 	struct jit_buf_desc jd;
789 	int ret;
790 
791 	/*
792 	 * first, detect marker mmap (i.e., the jitdump mmap)
793 	 */
794 	if (jit_detect(filename, pid)) {
795 		// Strip //anon* mmaps if we processed a jitdump for this pid
796 		if (jit_has_pid(machine, pid) && (strncmp(filename, "//anon", 6) == 0))
797 			return 1;
798 
799 		return 0;
800 	}
801 
802 	memset(&jd, 0, sizeof(jd));
803 
804 	jd.session = session;
805 	jd.output  = output;
806 	jd.machine = machine;
807 
808 	/*
809 	 * track sample_type to compute id_all layout
810 	 * perf sets the same sample type to all events as of now
811 	 */
812 	first = evlist__first(session->evlist);
813 	jd.sample_type = first->core.attr.sample_type;
814 
815 	*nbytes = 0;
816 
817 	ret = jit_inject(&jd, filename);
818 	if (!ret) {
819 		jit_add_pid(machine, pid);
820 		*nbytes = jd.bytes_written;
821 		ret = 1;
822 	}
823 
824 	return ret;
825 }
826