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 "namespaces.h"
22#include "symbol.h"
23#include <elf.h>
24
25#include "tsc.h"
26#include "session.h"
27#include "jit.h"
28#include "jitdump.h"
29#include "genelf.h"
30#include "thread.h"
31
32#include <linux/ctype.h>
33#include <linux/zalloc.h>
34
35struct jit_buf_desc {
36	struct perf_data *output;
37	struct perf_session *session;
38	struct machine *machine;
39	struct nsinfo  *nsi;
40	union jr_entry   *entry;
41	void             *buf;
42	uint64_t	 sample_type;
43	size_t           bufsize;
44	FILE             *in;
45	bool		 needs_bswap; /* handles cross-endianness */
46	bool		 use_arch_timestamp;
47	void		 *debug_data;
48	void		 *unwinding_data;
49	uint64_t	 unwinding_size;
50	uint64_t	 unwinding_mapped_size;
51	uint64_t         eh_frame_hdr_size;
52	size_t		 nr_debug_entries;
53	uint32_t         code_load_count;
54	u64		 bytes_written;
55	struct rb_root   code_root;
56	char		 dir[PATH_MAX];
57};
58
59struct jit_tool {
60	struct perf_tool tool;
61	struct perf_data	output;
62	struct perf_data	input;
63	u64 bytes_written;
64};
65
66#define hmax(a, b) ((a) > (b) ? (a) : (b))
67#define get_jit_tool(t) (container_of(tool, struct jit_tool, tool))
68
69static int
70jit_emit_elf(struct jit_buf_desc *jd,
71	     char *filename,
72	     const char *sym,
73	     uint64_t code_addr,
74	     const void *code,
75	     int csize,
76	     void *debug,
77	     int nr_debug_entries,
78	     void *unwinding,
79	     uint32_t unwinding_header_size,
80	     uint32_t unwinding_size)
81{
82	int ret, fd, saved_errno;
83	struct nscookie nsc;
84
85	if (verbose > 0)
86		fprintf(stderr, "write ELF image %s\n", filename);
87
88	nsinfo__mountns_enter(jd->nsi, &nsc);
89	fd = open(filename, O_CREAT|O_TRUNC|O_WRONLY, 0644);
90	saved_errno = errno;
91	nsinfo__mountns_exit(&nsc);
92	if (fd == -1) {
93		pr_warning("cannot create jit ELF %s: %s\n", filename, strerror(saved_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		nsinfo__mountns_enter(jd->nsi, &nsc);
104		unlink(filename);
105		nsinfo__mountns_exit(&nsc);
106	}
107
108	return ret;
109}
110
111static void
112jit_close(struct jit_buf_desc *jd)
113{
114	if (!(jd && jd->in))
115		return;
116	funlockfile(jd->in);
117	fclose(jd->in);
118	jd->in = NULL;
119}
120
121static int
122jit_validate_events(struct perf_session *session)
123{
124	struct evsel *evsel;
125
126	/*
127	 * check that all events use CLOCK_MONOTONIC
128	 */
129	evlist__for_each_entry(session->evlist, evsel) {
130		if (evsel->core.attr.use_clockid == 0 || evsel->core.attr.clockid != CLOCK_MONOTONIC)
131			return -1;
132	}
133	return 0;
134}
135
136static int
137jit_open(struct jit_buf_desc *jd, const char *name)
138{
139	struct jitheader header;
140	struct nscookie nsc;
141	struct jr_prefix *prefix;
142	ssize_t bs, bsz = 0;
143	void *n, *buf = NULL;
144	int ret, retval = -1;
145
146	nsinfo__mountns_enter(jd->nsi, &nsc);
147	jd->in = fopen(name, "r");
148	nsinfo__mountns_exit(&nsc);
149	if (!jd->in)
150		return -1;
151
152	bsz = hmax(sizeof(header), sizeof(*prefix));
153
154	buf = malloc(bsz);
155	if (!buf)
156		goto error;
157
158	/*
159	 * protect from writer modifying the file while we are reading it
160	 */
161	flockfile(jd->in);
162
163	ret = fread(buf, sizeof(header), 1, jd->in);
164	if (ret != 1)
165		goto error;
166
167	memcpy(&header, buf, sizeof(header));
168
169	if (header.magic != JITHEADER_MAGIC) {
170		if (header.magic != JITHEADER_MAGIC_SW)
171			goto error;
172		jd->needs_bswap = true;
173	}
174
175	if (jd->needs_bswap) {
176		header.version    = bswap_32(header.version);
177		header.total_size = bswap_32(header.total_size);
178		header.pid	  = bswap_32(header.pid);
179		header.elf_mach   = bswap_32(header.elf_mach);
180		header.timestamp  = bswap_64(header.timestamp);
181		header.flags      = bswap_64(header.flags);
182	}
183
184	jd->use_arch_timestamp = header.flags & JITDUMP_FLAGS_ARCH_TIMESTAMP;
185
186	if (verbose > 2)
187		pr_debug("version=%u\nhdr.size=%u\nts=0x%llx\npid=%d\nelf_mach=%d\nuse_arch_timestamp=%d\n",
188			header.version,
189			header.total_size,
190			(unsigned long long)header.timestamp,
191			header.pid,
192			header.elf_mach,
193			jd->use_arch_timestamp);
194
195	if (header.version > JITHEADER_VERSION) {
196		pr_err("wrong jitdump version %u, expected " __stringify(JITHEADER_VERSION),
197			header.version);
198		goto error;
199	}
200
201	if (header.flags & JITDUMP_FLAGS_RESERVED) {
202		pr_err("jitdump file contains invalid or unsupported flags 0x%llx\n",
203		       (unsigned long long)header.flags & JITDUMP_FLAGS_RESERVED);
204		goto error;
205	}
206
207	if (jd->use_arch_timestamp && !jd->session->time_conv.time_mult) {
208		pr_err("jitdump file uses arch timestamps but there is no timestamp conversion\n");
209		goto error;
210	}
211
212	/*
213	 * validate event is using the correct clockid
214	 */
215	if (!jd->use_arch_timestamp && jit_validate_events(jd->session)) {
216		pr_err("error, jitted code must be sampled with perf record -k 1\n");
217		goto error;
218	}
219
220	bs = header.total_size - sizeof(header);
221
222	if (bs > bsz) {
223		n = realloc(buf, bs);
224		if (!n)
225			goto error;
226		bsz = bs;
227		buf = n;
228		/* read extra we do not know about */
229		ret = fread(buf, bs - bsz, 1, jd->in);
230		if (ret != 1)
231			goto error;
232	}
233	/*
234	 * keep dirname for generating files and mmap records
235	 */
236	strcpy(jd->dir, name);
237	dirname(jd->dir);
238	free(buf);
239
240	return 0;
241error:
242	free(buf);
243	funlockfile(jd->in);
244	fclose(jd->in);
245	return retval;
246}
247
248static union jr_entry *
249jit_get_next_entry(struct jit_buf_desc *jd)
250{
251	struct jr_prefix *prefix;
252	union jr_entry *jr;
253	void *addr;
254	size_t bs, size;
255	int id, ret;
256
257	if (!(jd && jd->in))
258		return NULL;
259
260	if (jd->buf == NULL) {
261		size_t sz = getpagesize();
262		if (sz < sizeof(*prefix))
263			sz = sizeof(*prefix);
264
265		jd->buf = malloc(sz);
266		if (jd->buf == NULL)
267			return NULL;
268
269		jd->bufsize = sz;
270	}
271
272	prefix = jd->buf;
273
274	/*
275	 * file is still locked at this point
276	 */
277	ret = fread(prefix, sizeof(*prefix), 1, jd->in);
278	if (ret  != 1)
279		return NULL;
280
281	if (jd->needs_bswap) {
282		prefix->id   	   = bswap_32(prefix->id);
283		prefix->total_size = bswap_32(prefix->total_size);
284		prefix->timestamp  = bswap_64(prefix->timestamp);
285	}
286	id   = prefix->id;
287	size = prefix->total_size;
288
289	bs = (size_t)size;
290	if (bs < sizeof(*prefix))
291		return NULL;
292
293	if (id >= JIT_CODE_MAX) {
294		pr_warning("next_entry: unknown record type %d, skipping\n", id);
295	}
296	if (bs > jd->bufsize) {
297		void *n;
298		n = realloc(jd->buf, bs);
299		if (!n)
300			return NULL;
301		jd->buf = n;
302		jd->bufsize = bs;
303	}
304
305	addr = ((void *)jd->buf) + sizeof(*prefix);
306
307	ret = fread(addr, bs - sizeof(*prefix), 1, jd->in);
308	if (ret != 1)
309		return NULL;
310
311	jr = (union jr_entry *)jd->buf;
312
313	switch(id) {
314	case JIT_CODE_DEBUG_INFO:
315		if (jd->needs_bswap) {
316			uint64_t n;
317			jr->info.code_addr = bswap_64(jr->info.code_addr);
318			jr->info.nr_entry  = bswap_64(jr->info.nr_entry);
319			for (n = 0 ; n < jr->info.nr_entry; n++) {
320				jr->info.entries[n].addr    = bswap_64(jr->info.entries[n].addr);
321				jr->info.entries[n].lineno  = bswap_32(jr->info.entries[n].lineno);
322				jr->info.entries[n].discrim = bswap_32(jr->info.entries[n].discrim);
323			}
324		}
325		break;
326	case JIT_CODE_UNWINDING_INFO:
327		if (jd->needs_bswap) {
328			jr->unwinding.unwinding_size = bswap_64(jr->unwinding.unwinding_size);
329			jr->unwinding.eh_frame_hdr_size = bswap_64(jr->unwinding.eh_frame_hdr_size);
330			jr->unwinding.mapped_size = bswap_64(jr->unwinding.mapped_size);
331		}
332		break;
333	case JIT_CODE_CLOSE:
334		break;
335	case JIT_CODE_LOAD:
336		if (jd->needs_bswap) {
337			jr->load.pid       = bswap_32(jr->load.pid);
338			jr->load.tid       = bswap_32(jr->load.tid);
339			jr->load.vma       = bswap_64(jr->load.vma);
340			jr->load.code_addr = bswap_64(jr->load.code_addr);
341			jr->load.code_size = bswap_64(jr->load.code_size);
342			jr->load.code_index= bswap_64(jr->load.code_index);
343		}
344		jd->code_load_count++;
345		break;
346	case JIT_CODE_MOVE:
347		if (jd->needs_bswap) {
348			jr->move.pid           = bswap_32(jr->move.pid);
349			jr->move.tid           = bswap_32(jr->move.tid);
350			jr->move.vma           = bswap_64(jr->move.vma);
351			jr->move.old_code_addr = bswap_64(jr->move.old_code_addr);
352			jr->move.new_code_addr = bswap_64(jr->move.new_code_addr);
353			jr->move.code_size     = bswap_64(jr->move.code_size);
354			jr->move.code_index    = bswap_64(jr->move.code_index);
355		}
356		break;
357	case JIT_CODE_MAX:
358	default:
359		/* skip unknown record (we have read them) */
360		break;
361	}
362	return jr;
363}
364
365static int
366jit_inject_event(struct jit_buf_desc *jd, union perf_event *event)
367{
368	ssize_t size;
369
370	size = perf_data__write(jd->output, event, event->header.size);
371	if (size < 0)
372		return -1;
373
374	jd->bytes_written += size;
375	return 0;
376}
377
378static pid_t jr_entry_pid(struct jit_buf_desc *jd, union jr_entry *jr)
379{
380	if (jd->nsi && nsinfo__in_pidns(jd->nsi))
381		return nsinfo__tgid(jd->nsi);
382	return jr->load.pid;
383}
384
385static pid_t jr_entry_tid(struct jit_buf_desc *jd, union jr_entry *jr)
386{
387	if (jd->nsi && nsinfo__in_pidns(jd->nsi))
388		return nsinfo__pid(jd->nsi);
389	return jr->load.tid;
390}
391
392static uint64_t convert_timestamp(struct jit_buf_desc *jd, uint64_t timestamp)
393{
394	struct perf_tsc_conversion tc = { .time_shift = 0, };
395	struct perf_record_time_conv *time_conv = &jd->session->time_conv;
396
397	if (!jd->use_arch_timestamp)
398		return timestamp;
399
400	tc.time_shift = time_conv->time_shift;
401	tc.time_mult  = time_conv->time_mult;
402	tc.time_zero  = time_conv->time_zero;
403
404	/*
405	 * The event TIME_CONV was extended for the fields from "time_cycles"
406	 * when supported cap_user_time_short, for backward compatibility,
407	 * checks the event size and assigns these extended fields if these
408	 * fields are contained in the event.
409	 */
410	if (event_contains(*time_conv, time_cycles)) {
411		tc.time_cycles	       = time_conv->time_cycles;
412		tc.time_mask	       = time_conv->time_mask;
413		tc.cap_user_time_zero  = time_conv->cap_user_time_zero;
414		tc.cap_user_time_short = time_conv->cap_user_time_short;
415
416		if (!tc.cap_user_time_zero)
417			return 0;
418	}
419
420	return tsc_to_perf_time(timestamp, &tc);
421}
422
423static int jit_repipe_code_load(struct jit_buf_desc *jd, union jr_entry *jr)
424{
425	struct perf_sample sample;
426	union perf_event *event;
427	struct perf_tool *tool = jd->session->tool;
428	uint64_t code, addr;
429	uintptr_t uaddr;
430	char *filename;
431	struct stat st;
432	size_t size;
433	u16 idr_size;
434	const char *sym;
435	uint64_t count;
436	int ret, csize, usize;
437	pid_t nspid, pid, tid;
438	struct {
439		u32 pid, tid;
440		u64 time;
441	} *id;
442
443	nspid = jr->load.pid;
444	pid   = jr_entry_pid(jd, jr);
445	tid   = jr_entry_tid(jd, jr);
446	csize = jr->load.code_size;
447	usize = jd->unwinding_mapped_size;
448	addr  = jr->load.code_addr;
449	sym   = (void *)((unsigned long)jr + sizeof(jr->load));
450	code  = (unsigned long)jr + jr->load.p.total_size - csize;
451	count = jr->load.code_index;
452	idr_size = jd->machine->id_hdr_size;
453
454	event = calloc(1, sizeof(*event) + idr_size);
455	if (!event)
456		return -1;
457
458	filename = event->mmap2.filename;
459	size = snprintf(filename, PATH_MAX, "%s/jitted-%d-%" PRIu64 ".so",
460			jd->dir,
461			nspid,
462			count);
463
464	size++; /* for \0 */
465
466	size = PERF_ALIGN(size, sizeof(u64));
467	uaddr = (uintptr_t)code;
468	ret = jit_emit_elf(jd, filename, sym, addr, (const void *)uaddr, csize, jd->debug_data, jd->nr_debug_entries,
469			   jd->unwinding_data, jd->eh_frame_hdr_size, jd->unwinding_size);
470
471	if (jd->debug_data && jd->nr_debug_entries) {
472		zfree(&jd->debug_data);
473		jd->nr_debug_entries = 0;
474	}
475
476	if (jd->unwinding_data && jd->eh_frame_hdr_size) {
477		zfree(&jd->unwinding_data);
478		jd->eh_frame_hdr_size = 0;
479		jd->unwinding_mapped_size = 0;
480		jd->unwinding_size = 0;
481	}
482
483	if (ret) {
484		free(event);
485		return -1;
486	}
487	if (nsinfo__stat(filename, &st, jd->nsi))
488		memset(&st, 0, sizeof(st));
489
490	event->mmap2.header.type = PERF_RECORD_MMAP2;
491	event->mmap2.header.misc = PERF_RECORD_MISC_USER;
492	event->mmap2.header.size = (sizeof(event->mmap2) -
493			(sizeof(event->mmap2.filename) - size) + idr_size);
494
495	event->mmap2.pgoff = GEN_ELF_TEXT_OFFSET;
496	event->mmap2.start = addr;
497	event->mmap2.len   = usize ? ALIGN_8(csize) + usize : csize;
498	event->mmap2.pid   = pid;
499	event->mmap2.tid   = tid;
500	event->mmap2.ino   = st.st_ino;
501	event->mmap2.maj   = major(st.st_dev);
502	event->mmap2.min   = minor(st.st_dev);
503	event->mmap2.prot  = st.st_mode;
504	event->mmap2.flags = MAP_SHARED;
505	event->mmap2.ino_generation = 1;
506
507	id = (void *)((unsigned long)event + event->mmap.header.size - idr_size);
508	if (jd->sample_type & PERF_SAMPLE_TID) {
509		id->pid  = pid;
510		id->tid  = tid;
511	}
512	if (jd->sample_type & PERF_SAMPLE_TIME)
513		id->time = convert_timestamp(jd, jr->load.p.timestamp);
514
515	/*
516	 * create pseudo sample to induce dso hit increment
517	 * use first address as sample address
518	 */
519	memset(&sample, 0, sizeof(sample));
520	sample.cpumode = PERF_RECORD_MISC_USER;
521	sample.pid  = pid;
522	sample.tid  = tid;
523	sample.time = id->time;
524	sample.ip   = addr;
525
526	ret = perf_event__process_mmap2(tool, event, &sample, jd->machine);
527	if (ret)
528		goto out;
529
530	ret = jit_inject_event(jd, event);
531	/*
532	 * mark dso as use to generate buildid in the header
533	 */
534	if (!ret)
535		build_id__mark_dso_hit(tool, event, &sample, NULL, jd->machine);
536
537out:
538	free(event);
539	return ret;
540}
541
542static int jit_repipe_code_move(struct jit_buf_desc *jd, union jr_entry *jr)
543{
544	struct perf_sample sample;
545	union perf_event *event;
546	struct perf_tool *tool = jd->session->tool;
547	char *filename;
548	size_t size;
549	struct stat st;
550	int usize;
551	u16 idr_size;
552	int ret;
553	pid_t nspid, pid, tid;
554	struct {
555		u32 pid, tid;
556		u64 time;
557	} *id;
558
559	nspid = jr->load.pid;
560	pid   = jr_entry_pid(jd, jr);
561	tid   = jr_entry_tid(jd, jr);
562	usize = jd->unwinding_mapped_size;
563	idr_size = jd->machine->id_hdr_size;
564
565	/*
566	 * +16 to account for sample_id_all (hack)
567	 */
568	event = calloc(1, sizeof(*event) + 16);
569	if (!event)
570		return -1;
571
572	filename = event->mmap2.filename;
573	size = snprintf(filename, PATH_MAX, "%s/jitted-%d-%" PRIu64 ".so",
574	         jd->dir,
575		 nspid,
576		 jr->move.code_index);
577
578	size++; /* for \0 */
579
580	if (nsinfo__stat(filename, &st, jd->nsi))
581		memset(&st, 0, sizeof(st));
582
583	size = PERF_ALIGN(size, sizeof(u64));
584
585	event->mmap2.header.type = PERF_RECORD_MMAP2;
586	event->mmap2.header.misc = PERF_RECORD_MISC_USER;
587	event->mmap2.header.size = (sizeof(event->mmap2) -
588			(sizeof(event->mmap2.filename) - size) + idr_size);
589	event->mmap2.pgoff = GEN_ELF_TEXT_OFFSET;
590	event->mmap2.start = jr->move.new_code_addr;
591	event->mmap2.len   = usize ? ALIGN_8(jr->move.code_size) + usize
592				   : jr->move.code_size;
593	event->mmap2.pid   = pid;
594	event->mmap2.tid   = tid;
595	event->mmap2.ino   = st.st_ino;
596	event->mmap2.maj   = major(st.st_dev);
597	event->mmap2.min   = minor(st.st_dev);
598	event->mmap2.prot  = st.st_mode;
599	event->mmap2.flags = MAP_SHARED;
600	event->mmap2.ino_generation = 1;
601
602	id = (void *)((unsigned long)event + event->mmap.header.size - idr_size);
603	if (jd->sample_type & PERF_SAMPLE_TID) {
604		id->pid  = pid;
605		id->tid  = tid;
606	}
607	if (jd->sample_type & PERF_SAMPLE_TIME)
608		id->time = convert_timestamp(jd, jr->load.p.timestamp);
609
610	/*
611	 * create pseudo sample to induce dso hit increment
612	 * use first address as sample address
613	 */
614	memset(&sample, 0, sizeof(sample));
615	sample.cpumode = PERF_RECORD_MISC_USER;
616	sample.pid  = pid;
617	sample.tid  = tid;
618	sample.time = id->time;
619	sample.ip   = jr->move.new_code_addr;
620
621	ret = perf_event__process_mmap2(tool, event, &sample, jd->machine);
622	if (ret)
623		return ret;
624
625	ret = jit_inject_event(jd, event);
626	if (!ret)
627		build_id__mark_dso_hit(tool, event, &sample, NULL, jd->machine);
628
629	return ret;
630}
631
632static int jit_repipe_debug_info(struct jit_buf_desc *jd, union jr_entry *jr)
633{
634	void *data;
635	size_t sz;
636
637	if (!(jd && jr))
638		return -1;
639
640	sz  = jr->prefix.total_size - sizeof(jr->info);
641	data = malloc(sz);
642	if (!data)
643		return -1;
644
645	memcpy(data, &jr->info.entries, sz);
646
647	jd->debug_data       = data;
648
649	/*
650	 * we must use nr_entry instead of size here because
651	 * we cannot distinguish actual entry from padding otherwise
652	 */
653	jd->nr_debug_entries = jr->info.nr_entry;
654
655	return 0;
656}
657
658static int
659jit_repipe_unwinding_info(struct jit_buf_desc *jd, union jr_entry *jr)
660{
661	void *unwinding_data;
662	uint32_t unwinding_data_size;
663
664	if (!(jd && jr))
665		return -1;
666
667	unwinding_data_size  = jr->prefix.total_size - sizeof(jr->unwinding);
668	unwinding_data = malloc(unwinding_data_size);
669	if (!unwinding_data)
670		return -1;
671
672	memcpy(unwinding_data, &jr->unwinding.unwinding_data,
673	       unwinding_data_size);
674
675	jd->eh_frame_hdr_size = jr->unwinding.eh_frame_hdr_size;
676	jd->unwinding_size = jr->unwinding.unwinding_size;
677	jd->unwinding_mapped_size = jr->unwinding.mapped_size;
678	free(jd->unwinding_data);
679	jd->unwinding_data = unwinding_data;
680
681	return 0;
682}
683
684static int
685jit_process_dump(struct jit_buf_desc *jd)
686{
687	union jr_entry *jr;
688	int ret = 0;
689
690	while ((jr = jit_get_next_entry(jd))) {
691		switch(jr->prefix.id) {
692		case JIT_CODE_LOAD:
693			ret = jit_repipe_code_load(jd, jr);
694			break;
695		case JIT_CODE_MOVE:
696			ret = jit_repipe_code_move(jd, jr);
697			break;
698		case JIT_CODE_DEBUG_INFO:
699			ret = jit_repipe_debug_info(jd, jr);
700			break;
701		case JIT_CODE_UNWINDING_INFO:
702			ret = jit_repipe_unwinding_info(jd, jr);
703			break;
704		default:
705			ret = 0;
706			continue;
707		}
708	}
709	return ret;
710}
711
712static int
713jit_inject(struct jit_buf_desc *jd, char *path)
714{
715	int ret;
716
717	if (verbose > 0)
718		fprintf(stderr, "injecting: %s\n", path);
719
720	ret = jit_open(jd, path);
721	if (ret)
722		return -1;
723
724	ret = jit_process_dump(jd);
725
726	jit_close(jd);
727
728	if (verbose > 0)
729		fprintf(stderr, "injected: %s (%d)\n", path, ret);
730
731	return 0;
732}
733
734/*
735 * File must be with pattern .../jit-XXXX.dump
736 * where XXXX is the PID of the process which did the mmap()
737 * as captured in the RECORD_MMAP record
738 */
739static int
740jit_detect(char *mmap_name, pid_t pid, struct nsinfo *nsi)
741 {
742	char *p;
743	char *end = NULL;
744	pid_t pid2;
745
746	if (verbose > 2)
747		fprintf(stderr, "jit marker trying : %s\n", mmap_name);
748	/*
749	 * get file name
750	 */
751	p = strrchr(mmap_name, '/');
752	if (!p)
753		return -1;
754
755	/*
756	 * match prefix
757	 */
758	if (strncmp(p, "/jit-", 5))
759		return -1;
760
761	/*
762	 * skip prefix
763	 */
764	p += 5;
765
766	/*
767	 * must be followed by a pid
768	 */
769	if (!isdigit(*p))
770		return -1;
771
772	pid2 = (int)strtol(p, &end, 10);
773	if (!end)
774		return -1;
775
776	/*
777	 * pid does not match mmap pid
778	 * pid==0 in system-wide mode (synthesized)
779	 */
780	if (pid && pid2 != nsinfo__nstgid(nsi))
781		return -1;
782	/*
783	 * validate suffix
784	 */
785	if (strcmp(end, ".dump"))
786		return -1;
787
788	if (verbose > 0)
789		fprintf(stderr, "jit marker found: %s\n", mmap_name);
790
791	return 0;
792}
793
794static void jit_add_pid(struct machine *machine, pid_t pid)
795{
796	struct thread *thread = machine__findnew_thread(machine, pid, pid);
797
798	if (!thread) {
799		pr_err("%s: thread %d not found or created\n", __func__, pid);
800		return;
801	}
802
803	thread__set_priv(thread, (void *)true);
804	thread__put(thread);
805}
806
807static bool jit_has_pid(struct machine *machine, pid_t pid)
808{
809	struct thread *thread = machine__find_thread(machine, pid, pid);
810	void *priv;
811
812	if (!thread)
813		return false;
814
815	priv = thread__priv(thread);
816	thread__put(thread);
817	return (bool)priv;
818}
819
820int
821jit_process(struct perf_session *session,
822	    struct perf_data *output,
823	    struct machine *machine,
824	    char *filename,
825	    pid_t pid,
826	    pid_t tid,
827	    u64 *nbytes)
828{
829	struct thread *thread;
830	struct nsinfo *nsi;
831	struct evsel *first;
832	struct jit_buf_desc jd;
833	int ret;
834
835	thread = machine__findnew_thread(machine, pid, tid);
836	if (thread == NULL) {
837		pr_err("problem processing JIT mmap event, skipping it.\n");
838		return 0;
839	}
840
841	nsi = nsinfo__get(thread__nsinfo(thread));
842	thread__put(thread);
843
844	/*
845	 * first, detect marker mmap (i.e., the jitdump mmap)
846	 */
847	if (jit_detect(filename, pid, nsi)) {
848		nsinfo__put(nsi);
849
850		/*
851		 * Strip //anon*, [anon:* and /memfd:* mmaps if we processed a jitdump for this pid
852		 */
853		if (jit_has_pid(machine, pid) &&
854			((strncmp(filename, "//anon", 6) == 0) ||
855			 (strncmp(filename, "[anon:", 6) == 0) ||
856			 (strncmp(filename, "/memfd:", 7) == 0)))
857			return 1;
858
859		return 0;
860	}
861
862	memset(&jd, 0, sizeof(jd));
863
864	jd.session = session;
865	jd.output  = output;
866	jd.machine = machine;
867	jd.nsi = nsi;
868
869	/*
870	 * track sample_type to compute id_all layout
871	 * perf sets the same sample type to all events as of now
872	 */
873	first = evlist__first(session->evlist);
874	jd.sample_type = first->core.attr.sample_type;
875
876	*nbytes = 0;
877
878	ret = jit_inject(&jd, filename);
879	if (!ret) {
880		jit_add_pid(machine, pid);
881		*nbytes = jd.bytes_written;
882		ret = 1;
883	}
884
885	nsinfo__put(jd.nsi);
886	free(jd.buf);
887
888	return ret;
889}
890