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 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
69 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)70 jit_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
111 static void
jit_close(struct jit_buf_desc * jd)112 jit_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
121 static int
jit_validate_events(struct perf_session * session)122 jit_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
136 static int
jit_open(struct jit_buf_desc * jd,const char * name)137 jit_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
239 return 0;
240 error:
241 funlockfile(jd->in);
242 fclose(jd->in);
243 return retval;
244 }
245
246 static union jr_entry *
jit_get_next_entry(struct jit_buf_desc * jd)247 jit_get_next_entry(struct jit_buf_desc *jd)
248 {
249 struct jr_prefix *prefix;
250 union jr_entry *jr;
251 void *addr;
252 size_t bs, size;
253 int id, ret;
254
255 if (!(jd && jd->in))
256 return NULL;
257
258 if (jd->buf == NULL) {
259 size_t sz = getpagesize();
260 if (sz < sizeof(*prefix))
261 sz = sizeof(*prefix);
262
263 jd->buf = malloc(sz);
264 if (jd->buf == NULL)
265 return NULL;
266
267 jd->bufsize = sz;
268 }
269
270 prefix = jd->buf;
271
272 /*
273 * file is still locked at this point
274 */
275 ret = fread(prefix, sizeof(*prefix), 1, jd->in);
276 if (ret != 1)
277 return NULL;
278
279 if (jd->needs_bswap) {
280 prefix->id = bswap_32(prefix->id);
281 prefix->total_size = bswap_32(prefix->total_size);
282 prefix->timestamp = bswap_64(prefix->timestamp);
283 }
284 id = prefix->id;
285 size = prefix->total_size;
286
287 bs = (size_t)size;
288 if (bs < sizeof(*prefix))
289 return NULL;
290
291 if (id >= JIT_CODE_MAX) {
292 pr_warning("next_entry: unknown record type %d, skipping\n", id);
293 }
294 if (bs > jd->bufsize) {
295 void *n;
296 n = realloc(jd->buf, bs);
297 if (!n)
298 return NULL;
299 jd->buf = n;
300 jd->bufsize = bs;
301 }
302
303 addr = ((void *)jd->buf) + sizeof(*prefix);
304
305 ret = fread(addr, bs - sizeof(*prefix), 1, jd->in);
306 if (ret != 1)
307 return NULL;
308
309 jr = (union jr_entry *)jd->buf;
310
311 switch(id) {
312 case JIT_CODE_DEBUG_INFO:
313 if (jd->needs_bswap) {
314 uint64_t n;
315 jr->info.code_addr = bswap_64(jr->info.code_addr);
316 jr->info.nr_entry = bswap_64(jr->info.nr_entry);
317 for (n = 0 ; n < jr->info.nr_entry; n++) {
318 jr->info.entries[n].addr = bswap_64(jr->info.entries[n].addr);
319 jr->info.entries[n].lineno = bswap_32(jr->info.entries[n].lineno);
320 jr->info.entries[n].discrim = bswap_32(jr->info.entries[n].discrim);
321 }
322 }
323 break;
324 case JIT_CODE_UNWINDING_INFO:
325 if (jd->needs_bswap) {
326 jr->unwinding.unwinding_size = bswap_64(jr->unwinding.unwinding_size);
327 jr->unwinding.eh_frame_hdr_size = bswap_64(jr->unwinding.eh_frame_hdr_size);
328 jr->unwinding.mapped_size = bswap_64(jr->unwinding.mapped_size);
329 }
330 break;
331 case JIT_CODE_CLOSE:
332 break;
333 case JIT_CODE_LOAD:
334 if (jd->needs_bswap) {
335 jr->load.pid = bswap_32(jr->load.pid);
336 jr->load.tid = bswap_32(jr->load.tid);
337 jr->load.vma = bswap_64(jr->load.vma);
338 jr->load.code_addr = bswap_64(jr->load.code_addr);
339 jr->load.code_size = bswap_64(jr->load.code_size);
340 jr->load.code_index= bswap_64(jr->load.code_index);
341 }
342 jd->code_load_count++;
343 break;
344 case JIT_CODE_MOVE:
345 if (jd->needs_bswap) {
346 jr->move.pid = bswap_32(jr->move.pid);
347 jr->move.tid = bswap_32(jr->move.tid);
348 jr->move.vma = bswap_64(jr->move.vma);
349 jr->move.old_code_addr = bswap_64(jr->move.old_code_addr);
350 jr->move.new_code_addr = bswap_64(jr->move.new_code_addr);
351 jr->move.code_size = bswap_64(jr->move.code_size);
352 jr->move.code_index = bswap_64(jr->move.code_index);
353 }
354 break;
355 case JIT_CODE_MAX:
356 default:
357 /* skip unknown record (we have read them) */
358 break;
359 }
360 return jr;
361 }
362
363 static int
jit_inject_event(struct jit_buf_desc * jd,union perf_event * event)364 jit_inject_event(struct jit_buf_desc *jd, union perf_event *event)
365 {
366 ssize_t size;
367
368 size = perf_data__write(jd->output, event, event->header.size);
369 if (size < 0)
370 return -1;
371
372 jd->bytes_written += size;
373 return 0;
374 }
375
jr_entry_pid(struct jit_buf_desc * jd,union jr_entry * jr)376 static pid_t jr_entry_pid(struct jit_buf_desc *jd, union jr_entry *jr)
377 {
378 if (jd->nsi && nsinfo__in_pidns(jd->nsi))
379 return nsinfo__tgid(jd->nsi);
380 return jr->load.pid;
381 }
382
jr_entry_tid(struct jit_buf_desc * jd,union jr_entry * jr)383 static pid_t jr_entry_tid(struct jit_buf_desc *jd, union jr_entry *jr)
384 {
385 if (jd->nsi && nsinfo__in_pidns(jd->nsi))
386 return nsinfo__pid(jd->nsi);
387 return jr->load.tid;
388 }
389
convert_timestamp(struct jit_buf_desc * jd,uint64_t timestamp)390 static uint64_t convert_timestamp(struct jit_buf_desc *jd, uint64_t timestamp)
391 {
392 struct perf_tsc_conversion tc = { .time_shift = 0, };
393 struct perf_record_time_conv *time_conv = &jd->session->time_conv;
394
395 if (!jd->use_arch_timestamp)
396 return timestamp;
397
398 tc.time_shift = time_conv->time_shift;
399 tc.time_mult = time_conv->time_mult;
400 tc.time_zero = time_conv->time_zero;
401
402 /*
403 * The event TIME_CONV was extended for the fields from "time_cycles"
404 * when supported cap_user_time_short, for backward compatibility,
405 * checks the event size and assigns these extended fields if these
406 * fields are contained in the event.
407 */
408 if (event_contains(*time_conv, time_cycles)) {
409 tc.time_cycles = time_conv->time_cycles;
410 tc.time_mask = time_conv->time_mask;
411 tc.cap_user_time_zero = time_conv->cap_user_time_zero;
412 tc.cap_user_time_short = time_conv->cap_user_time_short;
413
414 if (!tc.cap_user_time_zero)
415 return 0;
416 }
417
418 return tsc_to_perf_time(timestamp, &tc);
419 }
420
jit_repipe_code_load(struct jit_buf_desc * jd,union jr_entry * jr)421 static int jit_repipe_code_load(struct jit_buf_desc *jd, union jr_entry *jr)
422 {
423 struct perf_sample sample;
424 union perf_event *event;
425 struct perf_tool *tool = jd->session->tool;
426 uint64_t code, addr;
427 uintptr_t uaddr;
428 char *filename;
429 struct stat st;
430 size_t size;
431 u16 idr_size;
432 const char *sym;
433 uint64_t count;
434 int ret, csize, usize;
435 pid_t nspid, pid, tid;
436 struct {
437 u32 pid, tid;
438 u64 time;
439 } *id;
440
441 nspid = jr->load.pid;
442 pid = jr_entry_pid(jd, jr);
443 tid = jr_entry_tid(jd, jr);
444 csize = jr->load.code_size;
445 usize = jd->unwinding_mapped_size;
446 addr = jr->load.code_addr;
447 sym = (void *)((unsigned long)jr + sizeof(jr->load));
448 code = (unsigned long)jr + jr->load.p.total_size - csize;
449 count = jr->load.code_index;
450 idr_size = jd->machine->id_hdr_size;
451
452 event = calloc(1, sizeof(*event) + idr_size);
453 if (!event)
454 return -1;
455
456 filename = event->mmap2.filename;
457 size = snprintf(filename, PATH_MAX, "%s/jitted-%d-%" PRIu64 ".so",
458 jd->dir,
459 nspid,
460 count);
461
462 size++; /* for \0 */
463
464 size = PERF_ALIGN(size, sizeof(u64));
465 uaddr = (uintptr_t)code;
466 ret = jit_emit_elf(jd, filename, sym, addr, (const void *)uaddr, csize, jd->debug_data, jd->nr_debug_entries,
467 jd->unwinding_data, jd->eh_frame_hdr_size, jd->unwinding_size);
468
469 if (jd->debug_data && jd->nr_debug_entries) {
470 zfree(&jd->debug_data);
471 jd->nr_debug_entries = 0;
472 }
473
474 if (jd->unwinding_data && jd->eh_frame_hdr_size) {
475 zfree(&jd->unwinding_data);
476 jd->eh_frame_hdr_size = 0;
477 jd->unwinding_mapped_size = 0;
478 jd->unwinding_size = 0;
479 }
480
481 if (ret) {
482 free(event);
483 return -1;
484 }
485 if (nsinfo__stat(filename, &st, jd->nsi))
486 memset(&st, 0, sizeof(st));
487
488 event->mmap2.header.type = PERF_RECORD_MMAP2;
489 event->mmap2.header.misc = PERF_RECORD_MISC_USER;
490 event->mmap2.header.size = (sizeof(event->mmap2) -
491 (sizeof(event->mmap2.filename) - size) + idr_size);
492
493 event->mmap2.pgoff = GEN_ELF_TEXT_OFFSET;
494 event->mmap2.start = addr;
495 event->mmap2.len = usize ? ALIGN_8(csize) + usize : csize;
496 event->mmap2.pid = pid;
497 event->mmap2.tid = tid;
498 event->mmap2.ino = st.st_ino;
499 event->mmap2.maj = major(st.st_dev);
500 event->mmap2.min = minor(st.st_dev);
501 event->mmap2.prot = st.st_mode;
502 event->mmap2.flags = MAP_SHARED;
503 event->mmap2.ino_generation = 1;
504
505 id = (void *)((unsigned long)event + event->mmap.header.size - idr_size);
506 if (jd->sample_type & PERF_SAMPLE_TID) {
507 id->pid = pid;
508 id->tid = tid;
509 }
510 if (jd->sample_type & PERF_SAMPLE_TIME)
511 id->time = convert_timestamp(jd, jr->load.p.timestamp);
512
513 /*
514 * create pseudo sample to induce dso hit increment
515 * use first address as sample address
516 */
517 memset(&sample, 0, sizeof(sample));
518 sample.cpumode = PERF_RECORD_MISC_USER;
519 sample.pid = pid;
520 sample.tid = tid;
521 sample.time = id->time;
522 sample.ip = addr;
523
524 ret = perf_event__process_mmap2(tool, event, &sample, jd->machine);
525 if (ret)
526 return ret;
527
528 ret = jit_inject_event(jd, event);
529 /*
530 * mark dso as use to generate buildid in the header
531 */
532 if (!ret)
533 build_id__mark_dso_hit(tool, event, &sample, NULL, jd->machine);
534
535 return ret;
536 }
537
jit_repipe_code_move(struct jit_buf_desc * jd,union jr_entry * jr)538 static int jit_repipe_code_move(struct jit_buf_desc *jd, union jr_entry *jr)
539 {
540 struct perf_sample sample;
541 union perf_event *event;
542 struct perf_tool *tool = jd->session->tool;
543 char *filename;
544 size_t size;
545 struct stat st;
546 int usize;
547 u16 idr_size;
548 int ret;
549 pid_t nspid, pid, tid;
550 struct {
551 u32 pid, tid;
552 u64 time;
553 } *id;
554
555 nspid = jr->load.pid;
556 pid = jr_entry_pid(jd, jr);
557 tid = jr_entry_tid(jd, jr);
558 usize = jd->unwinding_mapped_size;
559 idr_size = jd->machine->id_hdr_size;
560
561 /*
562 * +16 to account for sample_id_all (hack)
563 */
564 event = calloc(1, sizeof(*event) + 16);
565 if (!event)
566 return -1;
567
568 filename = event->mmap2.filename;
569 size = snprintf(filename, PATH_MAX, "%s/jitted-%d-%" PRIu64 ".so",
570 jd->dir,
571 nspid,
572 jr->move.code_index);
573
574 size++; /* for \0 */
575
576 if (nsinfo__stat(filename, &st, jd->nsi))
577 memset(&st, 0, sizeof(st));
578
579 size = PERF_ALIGN(size, sizeof(u64));
580
581 event->mmap2.header.type = PERF_RECORD_MMAP2;
582 event->mmap2.header.misc = PERF_RECORD_MISC_USER;
583 event->mmap2.header.size = (sizeof(event->mmap2) -
584 (sizeof(event->mmap2.filename) - size) + idr_size);
585 event->mmap2.pgoff = GEN_ELF_TEXT_OFFSET;
586 event->mmap2.start = jr->move.new_code_addr;
587 event->mmap2.len = usize ? ALIGN_8(jr->move.code_size) + usize
588 : jr->move.code_size;
589 event->mmap2.pid = pid;
590 event->mmap2.tid = tid;
591 event->mmap2.ino = st.st_ino;
592 event->mmap2.maj = major(st.st_dev);
593 event->mmap2.min = minor(st.st_dev);
594 event->mmap2.prot = st.st_mode;
595 event->mmap2.flags = MAP_SHARED;
596 event->mmap2.ino_generation = 1;
597
598 id = (void *)((unsigned long)event + event->mmap.header.size - idr_size);
599 if (jd->sample_type & PERF_SAMPLE_TID) {
600 id->pid = pid;
601 id->tid = tid;
602 }
603 if (jd->sample_type & PERF_SAMPLE_TIME)
604 id->time = convert_timestamp(jd, jr->load.p.timestamp);
605
606 /*
607 * create pseudo sample to induce dso hit increment
608 * use first address as sample address
609 */
610 memset(&sample, 0, sizeof(sample));
611 sample.cpumode = PERF_RECORD_MISC_USER;
612 sample.pid = pid;
613 sample.tid = tid;
614 sample.time = id->time;
615 sample.ip = jr->move.new_code_addr;
616
617 ret = perf_event__process_mmap2(tool, event, &sample, jd->machine);
618 if (ret)
619 return ret;
620
621 ret = jit_inject_event(jd, event);
622 if (!ret)
623 build_id__mark_dso_hit(tool, event, &sample, NULL, jd->machine);
624
625 return ret;
626 }
627
jit_repipe_debug_info(struct jit_buf_desc * jd,union jr_entry * jr)628 static int jit_repipe_debug_info(struct jit_buf_desc *jd, union jr_entry *jr)
629 {
630 void *data;
631 size_t sz;
632
633 if (!(jd && jr))
634 return -1;
635
636 sz = jr->prefix.total_size - sizeof(jr->info);
637 data = malloc(sz);
638 if (!data)
639 return -1;
640
641 memcpy(data, &jr->info.entries, sz);
642
643 jd->debug_data = data;
644
645 /*
646 * we must use nr_entry instead of size here because
647 * we cannot distinguish actual entry from padding otherwise
648 */
649 jd->nr_debug_entries = jr->info.nr_entry;
650
651 return 0;
652 }
653
654 static int
jit_repipe_unwinding_info(struct jit_buf_desc * jd,union jr_entry * jr)655 jit_repipe_unwinding_info(struct jit_buf_desc *jd, union jr_entry *jr)
656 {
657 void *unwinding_data;
658 uint32_t unwinding_data_size;
659
660 if (!(jd && jr))
661 return -1;
662
663 unwinding_data_size = jr->prefix.total_size - sizeof(jr->unwinding);
664 unwinding_data = malloc(unwinding_data_size);
665 if (!unwinding_data)
666 return -1;
667
668 memcpy(unwinding_data, &jr->unwinding.unwinding_data,
669 unwinding_data_size);
670
671 jd->eh_frame_hdr_size = jr->unwinding.eh_frame_hdr_size;
672 jd->unwinding_size = jr->unwinding.unwinding_size;
673 jd->unwinding_mapped_size = jr->unwinding.mapped_size;
674 jd->unwinding_data = unwinding_data;
675
676 return 0;
677 }
678
679 static int
jit_process_dump(struct jit_buf_desc * jd)680 jit_process_dump(struct jit_buf_desc *jd)
681 {
682 union jr_entry *jr;
683 int ret = 0;
684
685 while ((jr = jit_get_next_entry(jd))) {
686 switch(jr->prefix.id) {
687 case JIT_CODE_LOAD:
688 ret = jit_repipe_code_load(jd, jr);
689 break;
690 case JIT_CODE_MOVE:
691 ret = jit_repipe_code_move(jd, jr);
692 break;
693 case JIT_CODE_DEBUG_INFO:
694 ret = jit_repipe_debug_info(jd, jr);
695 break;
696 case JIT_CODE_UNWINDING_INFO:
697 ret = jit_repipe_unwinding_info(jd, jr);
698 break;
699 default:
700 ret = 0;
701 continue;
702 }
703 }
704 return ret;
705 }
706
707 static int
jit_inject(struct jit_buf_desc * jd,char * path)708 jit_inject(struct jit_buf_desc *jd, char *path)
709 {
710 int ret;
711
712 if (verbose > 0)
713 fprintf(stderr, "injecting: %s\n", path);
714
715 ret = jit_open(jd, path);
716 if (ret)
717 return -1;
718
719 ret = jit_process_dump(jd);
720
721 jit_close(jd);
722
723 if (verbose > 0)
724 fprintf(stderr, "injected: %s (%d)\n", path, ret);
725
726 return 0;
727 }
728
729 /*
730 * File must be with pattern .../jit-XXXX.dump
731 * where XXXX is the PID of the process which did the mmap()
732 * as captured in the RECORD_MMAP record
733 */
734 static int
jit_detect(char * mmap_name,pid_t pid,struct nsinfo * nsi)735 jit_detect(char *mmap_name, pid_t pid, struct nsinfo *nsi)
736 {
737 char *p;
738 char *end = NULL;
739 pid_t pid2;
740
741 if (verbose > 2)
742 fprintf(stderr, "jit marker trying : %s\n", mmap_name);
743 /*
744 * get file name
745 */
746 p = strrchr(mmap_name, '/');
747 if (!p)
748 return -1;
749
750 /*
751 * match prefix
752 */
753 if (strncmp(p, "/jit-", 5))
754 return -1;
755
756 /*
757 * skip prefix
758 */
759 p += 5;
760
761 /*
762 * must be followed by a pid
763 */
764 if (!isdigit(*p))
765 return -1;
766
767 pid2 = (int)strtol(p, &end, 10);
768 if (!end)
769 return -1;
770
771 /*
772 * pid does not match mmap pid
773 * pid==0 in system-wide mode (synthesized)
774 */
775 if (pid && pid2 != nsinfo__nstgid(nsi))
776 return -1;
777 /*
778 * validate suffix
779 */
780 if (strcmp(end, ".dump"))
781 return -1;
782
783 if (verbose > 0)
784 fprintf(stderr, "jit marker found: %s\n", mmap_name);
785
786 return 0;
787 }
788
jit_add_pid(struct machine * machine,pid_t pid)789 static void jit_add_pid(struct machine *machine, pid_t pid)
790 {
791 struct thread *thread = machine__findnew_thread(machine, pid, pid);
792
793 if (!thread) {
794 pr_err("%s: thread %d not found or created\n", __func__, pid);
795 return;
796 }
797
798 thread->priv = (void *)1;
799 }
800
jit_has_pid(struct machine * machine,pid_t pid)801 static bool jit_has_pid(struct machine *machine, pid_t pid)
802 {
803 struct thread *thread = machine__find_thread(machine, pid, pid);
804
805 if (!thread)
806 return 0;
807
808 return (bool)thread->priv;
809 }
810
811 int
jit_process(struct perf_session * session,struct perf_data * output,struct machine * machine,char * filename,pid_t pid,pid_t tid,u64 * nbytes)812 jit_process(struct perf_session *session,
813 struct perf_data *output,
814 struct machine *machine,
815 char *filename,
816 pid_t pid,
817 pid_t tid,
818 u64 *nbytes)
819 {
820 struct thread *thread;
821 struct nsinfo *nsi;
822 struct evsel *first;
823 struct jit_buf_desc jd;
824 int ret;
825
826 thread = machine__findnew_thread(machine, pid, tid);
827 if (thread == NULL) {
828 pr_err("problem processing JIT mmap event, skipping it.\n");
829 return 0;
830 }
831
832 nsi = nsinfo__get(thread->nsinfo);
833 thread__put(thread);
834
835 /*
836 * first, detect marker mmap (i.e., the jitdump mmap)
837 */
838 if (jit_detect(filename, pid, nsi)) {
839 nsinfo__put(nsi);
840
841 /*
842 * Strip //anon*, [anon:* and /memfd:* mmaps if we processed a jitdump for this pid
843 */
844 if (jit_has_pid(machine, pid) &&
845 ((strncmp(filename, "//anon", 6) == 0) ||
846 (strncmp(filename, "[anon:", 6) == 0) ||
847 (strncmp(filename, "/memfd:", 7) == 0)))
848 return 1;
849
850 return 0;
851 }
852
853 memset(&jd, 0, sizeof(jd));
854
855 jd.session = session;
856 jd.output = output;
857 jd.machine = machine;
858 jd.nsi = nsi;
859
860 /*
861 * track sample_type to compute id_all layout
862 * perf sets the same sample type to all events as of now
863 */
864 first = evlist__first(session->evlist);
865 jd.sample_type = first->core.attr.sample_type;
866
867 *nbytes = 0;
868
869 ret = jit_inject(&jd, filename);
870 if (!ret) {
871 jit_add_pid(machine, pid);
872 *nbytes = jd.bytes_written;
873 ret = 1;
874 }
875
876 nsinfo__put(jd.nsi);
877
878 return ret;
879 }
880