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