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 
35 struct 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 
59 struct debug_line_info {
60 	unsigned long vma;
61 	unsigned int lineno;
62 	/* The filename format is unspecified, absolute path, relative etc. */
63 	char const filename[];
64 };
65 
66 struct jit_tool {
67 	struct perf_tool tool;
68 	struct perf_data	output;
69 	struct perf_data	input;
70 	u64 bytes_written;
71 };
72 
73 #define hmax(a, b) ((a) > (b) ? (a) : (b))
74 #define get_jit_tool(t) (container_of(tool, struct jit_tool, tool))
75 
76 static int
jit_emit_elf(struct jit_buf_desc * jd,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)77 jit_emit_elf(struct jit_buf_desc *jd,
78 	     char *filename,
79 	     const char *sym,
80 	     uint64_t code_addr,
81 	     const void *code,
82 	     int csize,
83 	     void *debug,
84 	     int nr_debug_entries,
85 	     void *unwinding,
86 	     uint32_t unwinding_header_size,
87 	     uint32_t unwinding_size)
88 {
89 	int ret, fd, saved_errno;
90 	struct nscookie nsc;
91 
92 	if (verbose > 0)
93 		fprintf(stderr, "write ELF image %s\n", filename);
94 
95 	nsinfo__mountns_enter(jd->nsi, &nsc);
96 	fd = open(filename, O_CREAT|O_TRUNC|O_WRONLY, 0644);
97 	saved_errno = errno;
98 	nsinfo__mountns_exit(&nsc);
99 	if (fd == -1) {
100 		pr_warning("cannot create jit ELF %s: %s\n", filename, strerror(saved_errno));
101 		return -1;
102 	}
103 
104 	ret = jit_write_elf(fd, code_addr, sym, (const void *)code, csize, debug, nr_debug_entries,
105 			    unwinding, unwinding_header_size, unwinding_size);
106 
107         close(fd);
108 
109 	if (ret) {
110 		nsinfo__mountns_enter(jd->nsi, &nsc);
111 		unlink(filename);
112 		nsinfo__mountns_exit(&nsc);
113 	}
114 
115 	return ret;
116 }
117 
118 static void
jit_close(struct jit_buf_desc * jd)119 jit_close(struct jit_buf_desc *jd)
120 {
121 	if (!(jd && jd->in))
122 		return;
123 	funlockfile(jd->in);
124 	fclose(jd->in);
125 	jd->in = NULL;
126 }
127 
128 static int
jit_validate_events(struct perf_session * session)129 jit_validate_events(struct perf_session *session)
130 {
131 	struct evsel *evsel;
132 
133 	/*
134 	 * check that all events use CLOCK_MONOTONIC
135 	 */
136 	evlist__for_each_entry(session->evlist, evsel) {
137 		if (evsel->core.attr.use_clockid == 0 || evsel->core.attr.clockid != CLOCK_MONOTONIC)
138 			return -1;
139 	}
140 	return 0;
141 }
142 
143 static int
jit_open(struct jit_buf_desc * jd,const char * name)144 jit_open(struct jit_buf_desc *jd, const char *name)
145 {
146 	struct jitheader header;
147 	struct nscookie nsc;
148 	struct jr_prefix *prefix;
149 	ssize_t bs, bsz = 0;
150 	void *n, *buf = NULL;
151 	int ret, retval = -1;
152 
153 	nsinfo__mountns_enter(jd->nsi, &nsc);
154 	jd->in = fopen(name, "r");
155 	nsinfo__mountns_exit(&nsc);
156 	if (!jd->in)
157 		return -1;
158 
159 	bsz = hmax(sizeof(header), sizeof(*prefix));
160 
161 	buf = malloc(bsz);
162 	if (!buf)
163 		goto error;
164 
165 	/*
166 	 * protect from writer modifying the file while we are reading it
167 	 */
168 	flockfile(jd->in);
169 
170 	ret = fread(buf, sizeof(header), 1, jd->in);
171 	if (ret != 1)
172 		goto error;
173 
174 	memcpy(&header, buf, sizeof(header));
175 
176 	if (header.magic != JITHEADER_MAGIC) {
177 		if (header.magic != JITHEADER_MAGIC_SW)
178 			goto error;
179 		jd->needs_bswap = true;
180 	}
181 
182 	if (jd->needs_bswap) {
183 		header.version    = bswap_32(header.version);
184 		header.total_size = bswap_32(header.total_size);
185 		header.pid	  = bswap_32(header.pid);
186 		header.elf_mach   = bswap_32(header.elf_mach);
187 		header.timestamp  = bswap_64(header.timestamp);
188 		header.flags      = bswap_64(header.flags);
189 	}
190 
191 	jd->use_arch_timestamp = header.flags & JITDUMP_FLAGS_ARCH_TIMESTAMP;
192 
193 	if (verbose > 2)
194 		pr_debug("version=%u\nhdr.size=%u\nts=0x%llx\npid=%d\nelf_mach=%d\nuse_arch_timestamp=%d\n",
195 			header.version,
196 			header.total_size,
197 			(unsigned long long)header.timestamp,
198 			header.pid,
199 			header.elf_mach,
200 			jd->use_arch_timestamp);
201 
202 	if (header.version > JITHEADER_VERSION) {
203 		pr_err("wrong jitdump version %u, expected " __stringify(JITHEADER_VERSION),
204 			header.version);
205 		goto error;
206 	}
207 
208 	if (header.flags & JITDUMP_FLAGS_RESERVED) {
209 		pr_err("jitdump file contains invalid or unsupported flags 0x%llx\n",
210 		       (unsigned long long)header.flags & JITDUMP_FLAGS_RESERVED);
211 		goto error;
212 	}
213 
214 	if (jd->use_arch_timestamp && !jd->session->time_conv.time_mult) {
215 		pr_err("jitdump file uses arch timestamps but there is no timestamp conversion\n");
216 		goto error;
217 	}
218 
219 	/*
220 	 * validate event is using the correct clockid
221 	 */
222 	if (!jd->use_arch_timestamp && jit_validate_events(jd->session)) {
223 		pr_err("error, jitted code must be sampled with perf record -k 1\n");
224 		goto error;
225 	}
226 
227 	bs = header.total_size - sizeof(header);
228 
229 	if (bs > bsz) {
230 		n = realloc(buf, bs);
231 		if (!n)
232 			goto error;
233 		bsz = bs;
234 		buf = n;
235 		/* read extra we do not know about */
236 		ret = fread(buf, bs - bsz, 1, jd->in);
237 		if (ret != 1)
238 			goto error;
239 	}
240 	/*
241 	 * keep dirname for generating files and mmap records
242 	 */
243 	strcpy(jd->dir, name);
244 	dirname(jd->dir);
245 
246 	return 0;
247 error:
248 	funlockfile(jd->in);
249 	fclose(jd->in);
250 	return retval;
251 }
252 
253 static union jr_entry *
jit_get_next_entry(struct jit_buf_desc * jd)254 jit_get_next_entry(struct jit_buf_desc *jd)
255 {
256 	struct jr_prefix *prefix;
257 	union jr_entry *jr;
258 	void *addr;
259 	size_t bs, size;
260 	int id, ret;
261 
262 	if (!(jd && jd->in))
263 		return NULL;
264 
265 	if (jd->buf == NULL) {
266 		size_t sz = getpagesize();
267 		if (sz < sizeof(*prefix))
268 			sz = sizeof(*prefix);
269 
270 		jd->buf = malloc(sz);
271 		if (jd->buf == NULL)
272 			return NULL;
273 
274 		jd->bufsize = sz;
275 	}
276 
277 	prefix = jd->buf;
278 
279 	/*
280 	 * file is still locked at this point
281 	 */
282 	ret = fread(prefix, sizeof(*prefix), 1, jd->in);
283 	if (ret  != 1)
284 		return NULL;
285 
286 	if (jd->needs_bswap) {
287 		prefix->id   	   = bswap_32(prefix->id);
288 		prefix->total_size = bswap_32(prefix->total_size);
289 		prefix->timestamp  = bswap_64(prefix->timestamp);
290 	}
291 	id   = prefix->id;
292 	size = prefix->total_size;
293 
294 	bs = (size_t)size;
295 	if (bs < sizeof(*prefix))
296 		return NULL;
297 
298 	if (id >= JIT_CODE_MAX) {
299 		pr_warning("next_entry: unknown record type %d, skipping\n", id);
300 	}
301 	if (bs > jd->bufsize) {
302 		void *n;
303 		n = realloc(jd->buf, bs);
304 		if (!n)
305 			return NULL;
306 		jd->buf = n;
307 		jd->bufsize = bs;
308 	}
309 
310 	addr = ((void *)jd->buf) + sizeof(*prefix);
311 
312 	ret = fread(addr, bs - sizeof(*prefix), 1, jd->in);
313 	if (ret != 1)
314 		return NULL;
315 
316 	jr = (union jr_entry *)jd->buf;
317 
318 	switch(id) {
319 	case JIT_CODE_DEBUG_INFO:
320 		if (jd->needs_bswap) {
321 			uint64_t n;
322 			jr->info.code_addr = bswap_64(jr->info.code_addr);
323 			jr->info.nr_entry  = bswap_64(jr->info.nr_entry);
324 			for (n = 0 ; n < jr->info.nr_entry; n++) {
325 				jr->info.entries[n].addr    = bswap_64(jr->info.entries[n].addr);
326 				jr->info.entries[n].lineno  = bswap_32(jr->info.entries[n].lineno);
327 				jr->info.entries[n].discrim = bswap_32(jr->info.entries[n].discrim);
328 			}
329 		}
330 		break;
331 	case JIT_CODE_UNWINDING_INFO:
332 		if (jd->needs_bswap) {
333 			jr->unwinding.unwinding_size = bswap_64(jr->unwinding.unwinding_size);
334 			jr->unwinding.eh_frame_hdr_size = bswap_64(jr->unwinding.eh_frame_hdr_size);
335 			jr->unwinding.mapped_size = bswap_64(jr->unwinding.mapped_size);
336 		}
337 		break;
338 	case JIT_CODE_CLOSE:
339 		break;
340 	case JIT_CODE_LOAD:
341 		if (jd->needs_bswap) {
342 			jr->load.pid       = bswap_32(jr->load.pid);
343 			jr->load.tid       = bswap_32(jr->load.tid);
344 			jr->load.vma       = bswap_64(jr->load.vma);
345 			jr->load.code_addr = bswap_64(jr->load.code_addr);
346 			jr->load.code_size = bswap_64(jr->load.code_size);
347 			jr->load.code_index= bswap_64(jr->load.code_index);
348 		}
349 		jd->code_load_count++;
350 		break;
351 	case JIT_CODE_MOVE:
352 		if (jd->needs_bswap) {
353 			jr->move.pid           = bswap_32(jr->move.pid);
354 			jr->move.tid           = bswap_32(jr->move.tid);
355 			jr->move.vma           = bswap_64(jr->move.vma);
356 			jr->move.old_code_addr = bswap_64(jr->move.old_code_addr);
357 			jr->move.new_code_addr = bswap_64(jr->move.new_code_addr);
358 			jr->move.code_size     = bswap_64(jr->move.code_size);
359 			jr->move.code_index    = bswap_64(jr->move.code_index);
360 		}
361 		break;
362 	case JIT_CODE_MAX:
363 	default:
364 		/* skip unknown record (we have read them) */
365 		break;
366 	}
367 	return jr;
368 }
369 
370 static int
jit_inject_event(struct jit_buf_desc * jd,union perf_event * event)371 jit_inject_event(struct jit_buf_desc *jd, union perf_event *event)
372 {
373 	ssize_t size;
374 
375 	size = perf_data__write(jd->output, event, event->header.size);
376 	if (size < 0)
377 		return -1;
378 
379 	jd->bytes_written += size;
380 	return 0;
381 }
382 
jr_entry_pid(struct jit_buf_desc * jd,union jr_entry * jr)383 static pid_t jr_entry_pid(struct jit_buf_desc *jd, union jr_entry *jr)
384 {
385 	if (jd->nsi && nsinfo__in_pidns(jd->nsi))
386 		return nsinfo__tgid(jd->nsi);
387 	return jr->load.pid;
388 }
389 
jr_entry_tid(struct jit_buf_desc * jd,union jr_entry * jr)390 static pid_t jr_entry_tid(struct jit_buf_desc *jd, union jr_entry *jr)
391 {
392 	if (jd->nsi && nsinfo__in_pidns(jd->nsi))
393 		return nsinfo__pid(jd->nsi);
394 	return jr->load.tid;
395 }
396 
convert_timestamp(struct jit_buf_desc * jd,uint64_t timestamp)397 static uint64_t convert_timestamp(struct jit_buf_desc *jd, uint64_t timestamp)
398 {
399 	struct perf_tsc_conversion tc = { .time_shift = 0, };
400 	struct perf_record_time_conv *time_conv = &jd->session->time_conv;
401 
402 	if (!jd->use_arch_timestamp)
403 		return timestamp;
404 
405 	tc.time_shift = time_conv->time_shift;
406 	tc.time_mult  = time_conv->time_mult;
407 	tc.time_zero  = time_conv->time_zero;
408 
409 	/*
410 	 * The event TIME_CONV was extended for the fields from "time_cycles"
411 	 * when supported cap_user_time_short, for backward compatibility,
412 	 * checks the event size and assigns these extended fields if these
413 	 * fields are contained in the event.
414 	 */
415 	if (event_contains(*time_conv, time_cycles)) {
416 		tc.time_cycles	       = time_conv->time_cycles;
417 		tc.time_mask	       = time_conv->time_mask;
418 		tc.cap_user_time_zero  = time_conv->cap_user_time_zero;
419 		tc.cap_user_time_short = time_conv->cap_user_time_short;
420 
421 		if (!tc.cap_user_time_zero)
422 			return 0;
423 	}
424 
425 	return tsc_to_perf_time(timestamp, &tc);
426 }
427 
jit_repipe_code_load(struct jit_buf_desc * jd,union jr_entry * jr)428 static int jit_repipe_code_load(struct jit_buf_desc *jd, union jr_entry *jr)
429 {
430 	struct perf_sample sample;
431 	union perf_event *event;
432 	struct perf_tool *tool = jd->session->tool;
433 	uint64_t code, addr;
434 	uintptr_t uaddr;
435 	char *filename;
436 	struct stat st;
437 	size_t size;
438 	u16 idr_size;
439 	const char *sym;
440 	uint64_t count;
441 	int ret, csize, usize;
442 	pid_t nspid, pid, tid;
443 	struct {
444 		u32 pid, tid;
445 		u64 time;
446 	} *id;
447 
448 	nspid = jr->load.pid;
449 	pid   = jr_entry_pid(jd, jr);
450 	tid   = jr_entry_tid(jd, jr);
451 	csize = jr->load.code_size;
452 	usize = jd->unwinding_mapped_size;
453 	addr  = jr->load.code_addr;
454 	sym   = (void *)((unsigned long)jr + sizeof(jr->load));
455 	code  = (unsigned long)jr + jr->load.p.total_size - csize;
456 	count = jr->load.code_index;
457 	idr_size = jd->machine->id_hdr_size;
458 
459 	event = calloc(1, sizeof(*event) + idr_size);
460 	if (!event)
461 		return -1;
462 
463 	filename = event->mmap2.filename;
464 	size = snprintf(filename, PATH_MAX, "%s/jitted-%d-%" PRIu64 ".so",
465 			jd->dir,
466 			nspid,
467 			count);
468 
469 	size++; /* for \0 */
470 
471 	size = PERF_ALIGN(size, sizeof(u64));
472 	uaddr = (uintptr_t)code;
473 	ret = jit_emit_elf(jd, filename, sym, addr, (const void *)uaddr, csize, jd->debug_data, jd->nr_debug_entries,
474 			   jd->unwinding_data, jd->eh_frame_hdr_size, jd->unwinding_size);
475 
476 	if (jd->debug_data && jd->nr_debug_entries) {
477 		zfree(&jd->debug_data);
478 		jd->nr_debug_entries = 0;
479 	}
480 
481 	if (jd->unwinding_data && jd->eh_frame_hdr_size) {
482 		zfree(&jd->unwinding_data);
483 		jd->eh_frame_hdr_size = 0;
484 		jd->unwinding_mapped_size = 0;
485 		jd->unwinding_size = 0;
486 	}
487 
488 	if (ret) {
489 		free(event);
490 		return -1;
491 	}
492 	if (nsinfo__stat(filename, &st, jd->nsi))
493 		memset(&st, 0, sizeof(st));
494 
495 	event->mmap2.header.type = PERF_RECORD_MMAP2;
496 	event->mmap2.header.misc = PERF_RECORD_MISC_USER;
497 	event->mmap2.header.size = (sizeof(event->mmap2) -
498 			(sizeof(event->mmap2.filename) - size) + idr_size);
499 
500 	event->mmap2.pgoff = GEN_ELF_TEXT_OFFSET;
501 	event->mmap2.start = addr;
502 	event->mmap2.len   = usize ? ALIGN_8(csize) + usize : csize;
503 	event->mmap2.pid   = pid;
504 	event->mmap2.tid   = tid;
505 	event->mmap2.ino   = st.st_ino;
506 	event->mmap2.maj   = major(st.st_dev);
507 	event->mmap2.min   = minor(st.st_dev);
508 	event->mmap2.prot  = st.st_mode;
509 	event->mmap2.flags = MAP_SHARED;
510 	event->mmap2.ino_generation = 1;
511 
512 	id = (void *)((unsigned long)event + event->mmap.header.size - idr_size);
513 	if (jd->sample_type & PERF_SAMPLE_TID) {
514 		id->pid  = pid;
515 		id->tid  = tid;
516 	}
517 	if (jd->sample_type & PERF_SAMPLE_TIME)
518 		id->time = convert_timestamp(jd, jr->load.p.timestamp);
519 
520 	/*
521 	 * create pseudo sample to induce dso hit increment
522 	 * use first address as sample address
523 	 */
524 	memset(&sample, 0, sizeof(sample));
525 	sample.cpumode = PERF_RECORD_MISC_USER;
526 	sample.pid  = pid;
527 	sample.tid  = tid;
528 	sample.time = id->time;
529 	sample.ip   = addr;
530 
531 	ret = perf_event__process_mmap2(tool, event, &sample, jd->machine);
532 	if (ret)
533 		return ret;
534 
535 	ret = jit_inject_event(jd, event);
536 	/*
537 	 * mark dso as use to generate buildid in the header
538 	 */
539 	if (!ret)
540 		build_id__mark_dso_hit(tool, event, &sample, NULL, jd->machine);
541 
542 	return ret;
543 }
544 
jit_repipe_code_move(struct jit_buf_desc * jd,union jr_entry * jr)545 static int jit_repipe_code_move(struct jit_buf_desc *jd, union jr_entry *jr)
546 {
547 	struct perf_sample sample;
548 	union perf_event *event;
549 	struct perf_tool *tool = jd->session->tool;
550 	char *filename;
551 	size_t size;
552 	struct stat st;
553 	int usize;
554 	u16 idr_size;
555 	int ret;
556 	pid_t nspid, pid, tid;
557 	struct {
558 		u32 pid, tid;
559 		u64 time;
560 	} *id;
561 
562 	nspid = jr->load.pid;
563 	pid   = jr_entry_pid(jd, jr);
564 	tid   = jr_entry_tid(jd, jr);
565 	usize = jd->unwinding_mapped_size;
566 	idr_size = jd->machine->id_hdr_size;
567 
568 	/*
569 	 * +16 to account for sample_id_all (hack)
570 	 */
571 	event = calloc(1, sizeof(*event) + 16);
572 	if (!event)
573 		return -1;
574 
575 	filename = event->mmap2.filename;
576 	size = snprintf(filename, PATH_MAX, "%s/jitted-%d-%" PRIu64 ".so",
577 	         jd->dir,
578 		 nspid,
579 		 jr->move.code_index);
580 
581 	size++; /* for \0 */
582 
583 	if (nsinfo__stat(filename, &st, jd->nsi))
584 		memset(&st, 0, sizeof(st));
585 
586 	size = PERF_ALIGN(size, sizeof(u64));
587 
588 	event->mmap2.header.type = PERF_RECORD_MMAP2;
589 	event->mmap2.header.misc = PERF_RECORD_MISC_USER;
590 	event->mmap2.header.size = (sizeof(event->mmap2) -
591 			(sizeof(event->mmap2.filename) - size) + idr_size);
592 	event->mmap2.pgoff = GEN_ELF_TEXT_OFFSET;
593 	event->mmap2.start = jr->move.new_code_addr;
594 	event->mmap2.len   = usize ? ALIGN_8(jr->move.code_size) + usize
595 				   : jr->move.code_size;
596 	event->mmap2.pid   = pid;
597 	event->mmap2.tid   = tid;
598 	event->mmap2.ino   = st.st_ino;
599 	event->mmap2.maj   = major(st.st_dev);
600 	event->mmap2.min   = minor(st.st_dev);
601 	event->mmap2.prot  = st.st_mode;
602 	event->mmap2.flags = MAP_SHARED;
603 	event->mmap2.ino_generation = 1;
604 
605 	id = (void *)((unsigned long)event + event->mmap.header.size - idr_size);
606 	if (jd->sample_type & PERF_SAMPLE_TID) {
607 		id->pid  = pid;
608 		id->tid  = tid;
609 	}
610 	if (jd->sample_type & PERF_SAMPLE_TIME)
611 		id->time = convert_timestamp(jd, jr->load.p.timestamp);
612 
613 	/*
614 	 * create pseudo sample to induce dso hit increment
615 	 * use first address as sample address
616 	 */
617 	memset(&sample, 0, sizeof(sample));
618 	sample.cpumode = PERF_RECORD_MISC_USER;
619 	sample.pid  = pid;
620 	sample.tid  = tid;
621 	sample.time = id->time;
622 	sample.ip   = jr->move.new_code_addr;
623 
624 	ret = perf_event__process_mmap2(tool, event, &sample, jd->machine);
625 	if (ret)
626 		return ret;
627 
628 	ret = jit_inject_event(jd, event);
629 	if (!ret)
630 		build_id__mark_dso_hit(tool, event, &sample, NULL, jd->machine);
631 
632 	return ret;
633 }
634 
jit_repipe_debug_info(struct jit_buf_desc * jd,union jr_entry * jr)635 static int jit_repipe_debug_info(struct jit_buf_desc *jd, union jr_entry *jr)
636 {
637 	void *data;
638 	size_t sz;
639 
640 	if (!(jd && jr))
641 		return -1;
642 
643 	sz  = jr->prefix.total_size - sizeof(jr->info);
644 	data = malloc(sz);
645 	if (!data)
646 		return -1;
647 
648 	memcpy(data, &jr->info.entries, sz);
649 
650 	jd->debug_data       = data;
651 
652 	/*
653 	 * we must use nr_entry instead of size here because
654 	 * we cannot distinguish actual entry from padding otherwise
655 	 */
656 	jd->nr_debug_entries = jr->info.nr_entry;
657 
658 	return 0;
659 }
660 
661 static int
jit_repipe_unwinding_info(struct jit_buf_desc * jd,union jr_entry * jr)662 jit_repipe_unwinding_info(struct jit_buf_desc *jd, union jr_entry *jr)
663 {
664 	void *unwinding_data;
665 	uint32_t unwinding_data_size;
666 
667 	if (!(jd && jr))
668 		return -1;
669 
670 	unwinding_data_size  = jr->prefix.total_size - sizeof(jr->unwinding);
671 	unwinding_data = malloc(unwinding_data_size);
672 	if (!unwinding_data)
673 		return -1;
674 
675 	memcpy(unwinding_data, &jr->unwinding.unwinding_data,
676 	       unwinding_data_size);
677 
678 	jd->eh_frame_hdr_size = jr->unwinding.eh_frame_hdr_size;
679 	jd->unwinding_size = jr->unwinding.unwinding_size;
680 	jd->unwinding_mapped_size = jr->unwinding.mapped_size;
681 	jd->unwinding_data = unwinding_data;
682 
683 	return 0;
684 }
685 
686 static int
jit_process_dump(struct jit_buf_desc * jd)687 jit_process_dump(struct jit_buf_desc *jd)
688 {
689 	union jr_entry *jr;
690 	int ret = 0;
691 
692 	while ((jr = jit_get_next_entry(jd))) {
693 		switch(jr->prefix.id) {
694 		case JIT_CODE_LOAD:
695 			ret = jit_repipe_code_load(jd, jr);
696 			break;
697 		case JIT_CODE_MOVE:
698 			ret = jit_repipe_code_move(jd, jr);
699 			break;
700 		case JIT_CODE_DEBUG_INFO:
701 			ret = jit_repipe_debug_info(jd, jr);
702 			break;
703 		case JIT_CODE_UNWINDING_INFO:
704 			ret = jit_repipe_unwinding_info(jd, jr);
705 			break;
706 		default:
707 			ret = 0;
708 			continue;
709 		}
710 	}
711 	return ret;
712 }
713 
714 static int
jit_inject(struct jit_buf_desc * jd,char * path)715 jit_inject(struct jit_buf_desc *jd, char *path)
716 {
717 	int ret;
718 
719 	if (verbose > 0)
720 		fprintf(stderr, "injecting: %s\n", path);
721 
722 	ret = jit_open(jd, path);
723 	if (ret)
724 		return -1;
725 
726 	ret = jit_process_dump(jd);
727 
728 	jit_close(jd);
729 
730 	if (verbose > 0)
731 		fprintf(stderr, "injected: %s (%d)\n", path, ret);
732 
733 	return 0;
734 }
735 
736 /*
737  * File must be with pattern .../jit-XXXX.dump
738  * where XXXX is the PID of the process which did the mmap()
739  * as captured in the RECORD_MMAP record
740  */
741 static int
jit_detect(char * mmap_name,pid_t pid,struct nsinfo * nsi)742 jit_detect(char *mmap_name, pid_t pid, struct nsinfo *nsi)
743  {
744 	char *p;
745 	char *end = NULL;
746 	pid_t pid2;
747 
748 	if (verbose > 2)
749 		fprintf(stderr, "jit marker trying : %s\n", mmap_name);
750 	/*
751 	 * get file name
752 	 */
753 	p = strrchr(mmap_name, '/');
754 	if (!p)
755 		return -1;
756 
757 	/*
758 	 * match prefix
759 	 */
760 	if (strncmp(p, "/jit-", 5))
761 		return -1;
762 
763 	/*
764 	 * skip prefix
765 	 */
766 	p += 5;
767 
768 	/*
769 	 * must be followed by a pid
770 	 */
771 	if (!isdigit(*p))
772 		return -1;
773 
774 	pid2 = (int)strtol(p, &end, 10);
775 	if (!end)
776 		return -1;
777 
778 	/*
779 	 * pid does not match mmap pid
780 	 * pid==0 in system-wide mode (synthesized)
781 	 */
782 	if (pid && pid2 != nsinfo__nstgid(nsi))
783 		return -1;
784 	/*
785 	 * validate suffix
786 	 */
787 	if (strcmp(end, ".dump"))
788 		return -1;
789 
790 	if (verbose > 0)
791 		fprintf(stderr, "jit marker found: %s\n", mmap_name);
792 
793 	return 0;
794 }
795 
jit_add_pid(struct machine * machine,pid_t pid)796 static void jit_add_pid(struct machine *machine, pid_t pid)
797 {
798 	struct thread *thread = machine__findnew_thread(machine, pid, pid);
799 
800 	if (!thread) {
801 		pr_err("%s: thread %d not found or created\n", __func__, pid);
802 		return;
803 	}
804 
805 	thread->priv = (void *)1;
806 }
807 
jit_has_pid(struct machine * machine,pid_t pid)808 static bool jit_has_pid(struct machine *machine, pid_t pid)
809 {
810 	struct thread *thread = machine__find_thread(machine, pid, pid);
811 
812 	if (!thread)
813 		return 0;
814 
815 	return (bool)thread->priv;
816 }
817 
818 int
jit_process(struct perf_session * session,struct perf_data * output,struct machine * machine,char * filename,pid_t pid,pid_t tid,u64 * nbytes)819 jit_process(struct perf_session *session,
820 	    struct perf_data *output,
821 	    struct machine *machine,
822 	    char *filename,
823 	    pid_t pid,
824 	    pid_t tid,
825 	    u64 *nbytes)
826 {
827 	struct thread *thread;
828 	struct nsinfo *nsi;
829 	struct evsel *first;
830 	struct jit_buf_desc jd;
831 	int ret;
832 
833 	thread = machine__findnew_thread(machine, pid, tid);
834 	if (thread == NULL) {
835 		pr_err("problem processing JIT mmap event, skipping it.\n");
836 		return 0;
837 	}
838 
839 	nsi = nsinfo__get(thread->nsinfo);
840 	thread__put(thread);
841 
842 	/*
843 	 * first, detect marker mmap (i.e., the jitdump mmap)
844 	 */
845 	if (jit_detect(filename, pid, nsi)) {
846 		nsinfo__put(nsi);
847 
848 		// Strip //anon* mmaps if we processed a jitdump for this pid
849 		if (jit_has_pid(machine, pid) && (strncmp(filename, "//anon", 6) == 0))
850 			return 1;
851 
852 		return 0;
853 	}
854 
855 	memset(&jd, 0, sizeof(jd));
856 
857 	jd.session = session;
858 	jd.output  = output;
859 	jd.machine = machine;
860 	jd.nsi = nsi;
861 
862 	/*
863 	 * track sample_type to compute id_all layout
864 	 * perf sets the same sample type to all events as of now
865 	 */
866 	first = evlist__first(session->evlist);
867 	jd.sample_type = first->core.attr.sample_type;
868 
869 	*nbytes = 0;
870 
871 	ret = jit_inject(&jd, filename);
872 	if (!ret) {
873 		jit_add_pid(machine, pid);
874 		*nbytes = jd.bytes_written;
875 		ret = 1;
876 	}
877 
878 	nsinfo__put(jd.nsi);
879 
880 	return ret;
881 }
882