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Merge branch 'locking-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel...
[cris-mirror.git] / tools / perf / util / dso.c
blob36ef45b2e89d53b674374fcf30325b49b0a34bfc
1 // SPDX-License-Identifier: GPL-2.0
2 #include <asm/bug.h>
3 #include <linux/kernel.h>
4 #include <sys/time.h>
5 #include <sys/resource.h>
6 #include <sys/types.h>
7 #include <sys/stat.h>
8 #include <unistd.h>
9 #include <errno.h>
10 #include <fcntl.h>
11 #include "compress.h"
12 #include "path.h"
13 #include "symbol.h"
14 #include "srcline.h"
15 #include "dso.h"
16 #include "machine.h"
17 #include "auxtrace.h"
18 #include "util.h"
19 #include "debug.h"
20 #include "string2.h"
21 #include "vdso.h"
22
23 static const char * const debuglink_paths[] = {
24 "%.0s%s",
25 "%s/%s",
26 "%s/.debug/%s",
27 "/usr/lib/debug%s/%s"
28 };
29
30 char dso__symtab_origin(const struct dso *dso)
31 {
32 static const char origin[] = {
33 [DSO_BINARY_TYPE__KALLSYMS] = 'k',
34 [DSO_BINARY_TYPE__VMLINUX] = 'v',
35 [DSO_BINARY_TYPE__JAVA_JIT] = 'j',
36 [DSO_BINARY_TYPE__DEBUGLINK] = 'l',
37 [DSO_BINARY_TYPE__BUILD_ID_CACHE] = 'B',
38 [DSO_BINARY_TYPE__BUILD_ID_CACHE_DEBUGINFO] = 'D',
39 [DSO_BINARY_TYPE__FEDORA_DEBUGINFO] = 'f',
40 [DSO_BINARY_TYPE__UBUNTU_DEBUGINFO] = 'u',
41 [DSO_BINARY_TYPE__OPENEMBEDDED_DEBUGINFO] = 'o',
42 [DSO_BINARY_TYPE__BUILDID_DEBUGINFO] = 'b',
43 [DSO_BINARY_TYPE__SYSTEM_PATH_DSO] = 'd',
44 [DSO_BINARY_TYPE__SYSTEM_PATH_KMODULE] = 'K',
45 [DSO_BINARY_TYPE__SYSTEM_PATH_KMODULE_COMP] = 'm',
46 [DSO_BINARY_TYPE__GUEST_KALLSYMS] = 'g',
47 [DSO_BINARY_TYPE__GUEST_KMODULE] = 'G',
48 [DSO_BINARY_TYPE__GUEST_KMODULE_COMP] = 'M',
49 [DSO_BINARY_TYPE__GUEST_VMLINUX] = 'V',
50 };
51
52 if (dso == NULL || dso->symtab_type == DSO_BINARY_TYPE__NOT_FOUND)
53 return '!';
54 return origin[dso->symtab_type];
55 }
56
57 int dso__read_binary_type_filename(const struct dso *dso,
58 enum dso_binary_type type,
59 char *root_dir, char *filename, size_t size)
60 {
61 char build_id_hex[SBUILD_ID_SIZE];
62 int ret = 0;
63 size_t len;
64
65 switch (type) {
66 case DSO_BINARY_TYPE__DEBUGLINK:
67 {
68 const char *last_slash;
69 char dso_dir[PATH_MAX];
70 char symfile[PATH_MAX];
71 unsigned int i;
72
73 len = __symbol__join_symfs(filename, size, dso->long_name);
74 last_slash = filename + len;
75 while (last_slash != filename && *last_slash != '/')
76 last_slash--;
77
78 strncpy(dso_dir, filename, last_slash - filename);
79 dso_dir[last_slash-filename] = '\0';
80
81 if (!is_regular_file(filename)) {
82 ret = -1;
83 break;
84 }
85
86 ret = filename__read_debuglink(filename, symfile, PATH_MAX);
87 if (ret)
88 break;
89
90 /* Check predefined locations where debug file might reside */
91 ret = -1;
92 for (i = 0; i < ARRAY_SIZE(debuglink_paths); i++) {
93 snprintf(filename, size,
94 debuglink_paths[i], dso_dir, symfile);
95 if (is_regular_file(filename)) {
96 ret = 0;
97 break;
98 }
99 }
100
101 break;
102 }
103 case DSO_BINARY_TYPE__BUILD_ID_CACHE:
104 if (dso__build_id_filename(dso, filename, size, false) == NULL)
105 ret = -1;
106 break;
107
108 case DSO_BINARY_TYPE__BUILD_ID_CACHE_DEBUGINFO:
109 if (dso__build_id_filename(dso, filename, size, true) == NULL)
110 ret = -1;
111 break;
112
113 case DSO_BINARY_TYPE__FEDORA_DEBUGINFO:
114 len = __symbol__join_symfs(filename, size, "/usr/lib/debug");
115 snprintf(filename + len, size - len, "%s.debug", dso->long_name);
116 break;
117
118 case DSO_BINARY_TYPE__UBUNTU_DEBUGINFO:
119 len = __symbol__join_symfs(filename, size, "/usr/lib/debug");
120 snprintf(filename + len, size - len, "%s", dso->long_name);
121 break;
122
123 case DSO_BINARY_TYPE__OPENEMBEDDED_DEBUGINFO:
124 {
125 const char *last_slash;
126 size_t dir_size;
127
128 last_slash = dso->long_name + dso->long_name_len;
129 while (last_slash != dso->long_name && *last_slash != '/')
130 last_slash--;
131
132 len = __symbol__join_symfs(filename, size, "");
133 dir_size = last_slash - dso->long_name + 2;
134 if (dir_size > (size - len)) {
135 ret = -1;
136 break;
137 }
138 len += scnprintf(filename + len, dir_size, "%s", dso->long_name);
139 len += scnprintf(filename + len , size - len, ".debug%s",
140 last_slash);
141 break;
142 }
143
144 case DSO_BINARY_TYPE__BUILDID_DEBUGINFO:
145 if (!dso->has_build_id) {
146 ret = -1;
147 break;
148 }
149
150 build_id__sprintf(dso->build_id,
151 sizeof(dso->build_id),
152 build_id_hex);
153 len = __symbol__join_symfs(filename, size, "/usr/lib/debug/.build-id/");
154 snprintf(filename + len, size - len, "%.2s/%s.debug",
155 build_id_hex, build_id_hex + 2);
156 break;
157
158 case DSO_BINARY_TYPE__VMLINUX:
159 case DSO_BINARY_TYPE__GUEST_VMLINUX:
160 case DSO_BINARY_TYPE__SYSTEM_PATH_DSO:
161 __symbol__join_symfs(filename, size, dso->long_name);
162 break;
163
164 case DSO_BINARY_TYPE__GUEST_KMODULE:
165 case DSO_BINARY_TYPE__GUEST_KMODULE_COMP:
166 path__join3(filename, size, symbol_conf.symfs,
167 root_dir, dso->long_name);
168 break;
169
170 case DSO_BINARY_TYPE__SYSTEM_PATH_KMODULE:
171 case DSO_BINARY_TYPE__SYSTEM_PATH_KMODULE_COMP:
172 __symbol__join_symfs(filename, size, dso->long_name);
173 break;
174
175 case DSO_BINARY_TYPE__KCORE:
176 case DSO_BINARY_TYPE__GUEST_KCORE:
177 snprintf(filename, size, "%s", dso->long_name);
178 break;
179
180 default:
181 case DSO_BINARY_TYPE__KALLSYMS:
182 case DSO_BINARY_TYPE__GUEST_KALLSYMS:
183 case DSO_BINARY_TYPE__JAVA_JIT:
184 case DSO_BINARY_TYPE__NOT_FOUND:
185 ret = -1;
186 break;
187 }
188
189 return ret;
190 }
191
192 static const struct {
193 const char *fmt;
194 int (*decompress)(const char *input, int output);
195 } compressions[] = {
196 #ifdef HAVE_ZLIB_SUPPORT
197 { "gz", gzip_decompress_to_file },
198 #endif
199 #ifdef HAVE_LZMA_SUPPORT
200 { "xz", lzma_decompress_to_file },
201 #endif
202 { NULL, NULL },
203 };
204
205 bool is_supported_compression(const char *ext)
206 {
207 unsigned i;
208
209 for (i = 0; compressions[i].fmt; i++) {
210 if (!strcmp(ext, compressions[i].fmt))
211 return true;
212 }
213 return false;
214 }
215
216 bool is_kernel_module(const char *pathname, int cpumode)
217 {
218 struct kmod_path m;
219 int mode = cpumode & PERF_RECORD_MISC_CPUMODE_MASK;
220
221 WARN_ONCE(mode != cpumode,
222 "Internal error: passing unmasked cpumode (%x) to is_kernel_module",
223 cpumode);
224
225 switch (mode) {
226 case PERF_RECORD_MISC_USER:
227 case PERF_RECORD_MISC_HYPERVISOR:
228 case PERF_RECORD_MISC_GUEST_USER:
229 return false;
230 /* Treat PERF_RECORD_MISC_CPUMODE_UNKNOWN as kernel */
231 default:
232 if (kmod_path__parse(&m, pathname)) {
233 pr_err("Failed to check whether %s is a kernel module or not. Assume it is.",
234 pathname);
235 return true;
236 }
237 }
238
239 return m.kmod;
240 }
241
242 bool decompress_to_file(const char *ext, const char *filename, int output_fd)
243 {
244 unsigned i;
245
246 for (i = 0; compressions[i].fmt; i++) {
247 if (!strcmp(ext, compressions[i].fmt))
248 return !compressions[i].decompress(filename,
249 output_fd);
250 }
251 return false;
252 }
253
254 bool dso__needs_decompress(struct dso *dso)
255 {
256 return dso->symtab_type == DSO_BINARY_TYPE__SYSTEM_PATH_KMODULE_COMP ||
257 dso->symtab_type == DSO_BINARY_TYPE__GUEST_KMODULE_COMP;
258 }
259
260 static int decompress_kmodule(struct dso *dso, const char *name, char *tmpbuf)
261 {
262 int fd = -1;
263 struct kmod_path m;
264
265 if (!dso__needs_decompress(dso))
266 return -1;
267
268 if (kmod_path__parse_ext(&m, dso->long_name))
269 return -1;
270
271 if (!m.comp)
272 goto out;
273
274 fd = mkstemp(tmpbuf);
275 if (fd < 0) {
276 dso->load_errno = errno;
277 goto out;
278 }
279
280 if (!decompress_to_file(m.ext, name, fd)) {
281 dso->load_errno = DSO_LOAD_ERRNO__DECOMPRESSION_FAILURE;
282 close(fd);
283 fd = -1;
284 }
285
286 out:
287 free(m.ext);
288 return fd;
289 }
290
291 int dso__decompress_kmodule_fd(struct dso *dso, const char *name)
292 {
293 char tmpbuf[] = KMOD_DECOMP_NAME;
294 int fd;
295
296 fd = decompress_kmodule(dso, name, tmpbuf);
297 unlink(tmpbuf);
298 return fd;
299 }
300
301 int dso__decompress_kmodule_path(struct dso *dso, const char *name,
302 char *pathname, size_t len)
303 {
304 char tmpbuf[] = KMOD_DECOMP_NAME;
305 int fd;
306
307 fd = decompress_kmodule(dso, name, tmpbuf);
308 if (fd < 0) {
309 unlink(tmpbuf);
310 return -1;
311 }
312
313 strncpy(pathname, tmpbuf, len);
314 close(fd);
315 return 0;
316 }
317
318 /*
319 * Parses kernel module specified in @path and updates
320 * @m argument like:
321 *
322 * @comp - true if @path contains supported compression suffix,
323 * false otherwise
324 * @kmod - true if @path contains '.ko' suffix in right position,
325 * false otherwise
326 * @name - if (@alloc_name && @kmod) is true, it contains strdup-ed base name
327 * of the kernel module without suffixes, otherwise strudup-ed
328 * base name of @path
329 * @ext - if (@alloc_ext && @comp) is true, it contains strdup-ed string
330 * the compression suffix
331 *
332 * Returns 0 if there's no strdup error, -ENOMEM otherwise.
333 */
334 int __kmod_path__parse(struct kmod_path *m, const char *path,
335 bool alloc_name, bool alloc_ext)
336 {
337 const char *name = strrchr(path, '/');
338 const char *ext = strrchr(path, '.');
339 bool is_simple_name = false;
340
341 memset(m, 0x0, sizeof(*m));
342 name = name ? name + 1 : path;
343
344 /*
345 * '.' is also a valid character for module name. For example:
346 * [aaa.bbb] is a valid module name. '[' should have higher
347 * priority than '.ko' suffix.
348 *
349 * The kernel names are from machine__mmap_name. Such
350 * name should belong to kernel itself, not kernel module.
351 */
352 if (name[0] == '[') {
353 is_simple_name = true;
354 if ((strncmp(name, "[kernel.kallsyms]", 17) == 0) ||
355 (strncmp(name, "[guest.kernel.kallsyms", 22) == 0) ||
356 (strncmp(name, "[vdso]", 6) == 0) ||
357 (strncmp(name, "[vsyscall]", 10) == 0)) {
358 m->kmod = false;
359
360 } else
361 m->kmod = true;
362 }
363
364 /* No extension, just return name. */
365 if ((ext == NULL) || is_simple_name) {
366 if (alloc_name) {
367 m->name = strdup(name);
368 return m->name ? 0 : -ENOMEM;
369 }
370 return 0;
371 }
372
373 if (is_supported_compression(ext + 1)) {
374 m->comp = true;
375 ext -= 3;
376 }
377
378 /* Check .ko extension only if there's enough name left. */
379 if (ext > name)
380 m->kmod = !strncmp(ext, ".ko", 3);
381
382 if (alloc_name) {
383 if (m->kmod) {
384 if (asprintf(&m->name, "[%.*s]", (int) (ext - name), name) == -1)
385 return -ENOMEM;
386 } else {
387 if (asprintf(&m->name, "%s", name) == -1)
388 return -ENOMEM;
389 }
390
391 strxfrchar(m->name, '-', '_');
392 }
393
394 if (alloc_ext && m->comp) {
395 m->ext = strdup(ext + 4);
396 if (!m->ext) {
397 free((void *) m->name);
398 return -ENOMEM;
399 }
400 }
401
402 return 0;
403 }
404
405 void dso__set_module_info(struct dso *dso, struct kmod_path *m,
406 struct machine *machine)
407 {
408 if (machine__is_host(machine))
409 dso->symtab_type = DSO_BINARY_TYPE__SYSTEM_PATH_KMODULE;
410 else
411 dso->symtab_type = DSO_BINARY_TYPE__GUEST_KMODULE;
412
413 /* _KMODULE_COMP should be next to _KMODULE */
414 if (m->kmod && m->comp)
415 dso->symtab_type++;
416
417 dso__set_short_name(dso, strdup(m->name), true);
418 }
419
420 /*
421 * Global list of open DSOs and the counter.
422 */
423 static LIST_HEAD(dso__data_open);
424 static long dso__data_open_cnt;
425 static pthread_mutex_t dso__data_open_lock = PTHREAD_MUTEX_INITIALIZER;
426
427 static void dso__list_add(struct dso *dso)
428 {
429 list_add_tail(&dso->data.open_entry, &dso__data_open);
430 dso__data_open_cnt++;
431 }
432
433 static void dso__list_del(struct dso *dso)
434 {
435 list_del(&dso->data.open_entry);
436 WARN_ONCE(dso__data_open_cnt <= 0,
437 "DSO data fd counter out of bounds.");
438 dso__data_open_cnt--;
439 }
440
441 static void close_first_dso(void);
442
443 static int do_open(char *name)
444 {
445 int fd;
446 char sbuf[STRERR_BUFSIZE];
447
448 do {
449 fd = open(name, O_RDONLY|O_CLOEXEC);
450 if (fd >= 0)
451 return fd;
452
453 pr_debug("dso open failed: %s\n",
454 str_error_r(errno, sbuf, sizeof(sbuf)));
455 if (!dso__data_open_cnt || errno != EMFILE)
456 break;
457
458 close_first_dso();
459 } while (1);
460
461 return -1;
462 }
463
464 static int __open_dso(struct dso *dso, struct machine *machine)
465 {
466 int fd = -EINVAL;
467 char *root_dir = (char *)"";
468 char *name = malloc(PATH_MAX);
469
470 if (!name)
471 return -ENOMEM;
472
473 if (machine)
474 root_dir = machine->root_dir;
475
476 if (dso__read_binary_type_filename(dso, dso->binary_type,
477 root_dir, name, PATH_MAX))
478 goto out;
479
480 if (!is_regular_file(name))
481 goto out;
482
483 if (dso__needs_decompress(dso)) {
484 char newpath[KMOD_DECOMP_LEN];
485 size_t len = sizeof(newpath);
486
487 if (dso__decompress_kmodule_path(dso, name, newpath, len) < 0) {
488 fd = -dso->load_errno;
489 goto out;
490 }
491
492 strcpy(name, newpath);
493 }
494
495 fd = do_open(name);
496
497 if (dso__needs_decompress(dso))
498 unlink(name);
499
500 out:
501 free(name);
502 return fd;
503 }
504
505 static void check_data_close(void);
506
507 /**
508 * dso_close - Open DSO data file
509 * @dso: dso object
510 *
511 * Open @dso's data file descriptor and updates
512 * list/count of open DSO objects.
513 */
514 static int open_dso(struct dso *dso, struct machine *machine)
515 {
516 int fd;
517 struct nscookie nsc;
518
519 if (dso->binary_type != DSO_BINARY_TYPE__BUILD_ID_CACHE)
520 nsinfo__mountns_enter(dso->nsinfo, &nsc);
521 fd = __open_dso(dso, machine);
522 if (dso->binary_type != DSO_BINARY_TYPE__BUILD_ID_CACHE)
523 nsinfo__mountns_exit(&nsc);
524
525 if (fd >= 0) {
526 dso__list_add(dso);
527 /*
528 * Check if we crossed the allowed number
529 * of opened DSOs and close one if needed.
530 */
531 check_data_close();
532 }
533
534 return fd;
535 }
536
537 static void close_data_fd(struct dso *dso)
538 {
539 if (dso->data.fd >= 0) {
540 close(dso->data.fd);
541 dso->data.fd = -1;
542 dso->data.file_size = 0;
543 dso__list_del(dso);
544 }
545 }
546
547 /**
548 * dso_close - Close DSO data file
549 * @dso: dso object
550 *
551 * Close @dso's data file descriptor and updates
552 * list/count of open DSO objects.
553 */
554 static void close_dso(struct dso *dso)
555 {
556 close_data_fd(dso);
557 }
558
559 static void close_first_dso(void)
560 {
561 struct dso *dso;
562
563 dso = list_first_entry(&dso__data_open, struct dso, data.open_entry);
564 close_dso(dso);
565 }
566
567 static rlim_t get_fd_limit(void)
568 {
569 struct rlimit l;
570 rlim_t limit = 0;
571
572 /* Allow half of the current open fd limit. */
573 if (getrlimit(RLIMIT_NOFILE, &l) == 0) {
574 if (l.rlim_cur == RLIM_INFINITY)
575 limit = l.rlim_cur;
576 else
577 limit = l.rlim_cur / 2;
578 } else {
579 pr_err("failed to get fd limit\n");
580 limit = 1;
581 }
582
583 return limit;
584 }
585
586 static rlim_t fd_limit;
587
588 /*
589 * Used only by tests/dso-data.c to reset the environment
590 * for tests. I dont expect we should change this during
591 * standard runtime.
592 */
593 void reset_fd_limit(void)
594 {
595 fd_limit = 0;
596 }
597
598 static bool may_cache_fd(void)
599 {
600 if (!fd_limit)
601 fd_limit = get_fd_limit();
602
603 if (fd_limit == RLIM_INFINITY)
604 return true;
605
606 return fd_limit > (rlim_t) dso__data_open_cnt;
607 }
608
609 /*
610 * Check and close LRU dso if we crossed allowed limit
611 * for opened dso file descriptors. The limit is half
612 * of the RLIMIT_NOFILE files opened.
613 */
614 static void check_data_close(void)
615 {
616 bool cache_fd = may_cache_fd();
617
618 if (!cache_fd)
619 close_first_dso();
620 }
621
622 /**
623 * dso__data_close - Close DSO data file
624 * @dso: dso object
625 *
626 * External interface to close @dso's data file descriptor.
627 */
628 void dso__data_close(struct dso *dso)
629 {
630 pthread_mutex_lock(&dso__data_open_lock);
631 close_dso(dso);
632 pthread_mutex_unlock(&dso__data_open_lock);
633 }
634
635 static void try_to_open_dso(struct dso *dso, struct machine *machine)
636 {
637 enum dso_binary_type binary_type_data[] = {
638 DSO_BINARY_TYPE__BUILD_ID_CACHE,
639 DSO_BINARY_TYPE__SYSTEM_PATH_DSO,
640 DSO_BINARY_TYPE__NOT_FOUND,
641 };
642 int i = 0;
643
644 if (dso->data.fd >= 0)
645 return;
646
647 if (dso->binary_type != DSO_BINARY_TYPE__NOT_FOUND) {
648 dso->data.fd = open_dso(dso, machine);
649 goto out;
650 }
651
652 do {
653 dso->binary_type = binary_type_data[i++];
654
655 dso->data.fd = open_dso(dso, machine);
656 if (dso->data.fd >= 0)
657 goto out;
658
659 } while (dso->binary_type != DSO_BINARY_TYPE__NOT_FOUND);
660 out:
661 if (dso->data.fd >= 0)
662 dso->data.status = DSO_DATA_STATUS_OK;
663 else
664 dso->data.status = DSO_DATA_STATUS_ERROR;
665 }
666
667 /**
668 * dso__data_get_fd - Get dso's data file descriptor
669 * @dso: dso object
670 * @machine: machine object
671 *
672 * External interface to find dso's file, open it and
673 * returns file descriptor. It should be paired with
674 * dso__data_put_fd() if it returns non-negative value.
675 */
676 int dso__data_get_fd(struct dso *dso, struct machine *machine)
677 {
678 if (dso->data.status == DSO_DATA_STATUS_ERROR)
679 return -1;
680
681 if (pthread_mutex_lock(&dso__data_open_lock) < 0)
682 return -1;
683
684 try_to_open_dso(dso, machine);
685
686 if (dso->data.fd < 0)
687 pthread_mutex_unlock(&dso__data_open_lock);
688
689 return dso->data.fd;
690 }
691
692 void dso__data_put_fd(struct dso *dso __maybe_unused)
693 {
694 pthread_mutex_unlock(&dso__data_open_lock);
695 }
696
697 bool dso__data_status_seen(struct dso *dso, enum dso_data_status_seen by)
698 {
699 u32 flag = 1 << by;
700
701 if (dso->data.status_seen & flag)
702 return true;
703
704 dso->data.status_seen |= flag;
705
706 return false;
707 }
708
709 static void
710 dso_cache__free(struct dso *dso)
711 {
712 struct rb_root *root = &dso->data.cache;
713 struct rb_node *next = rb_first(root);
714
715 pthread_mutex_lock(&dso->lock);
716 while (next) {
717 struct dso_cache *cache;
718
719 cache = rb_entry(next, struct dso_cache, rb_node);
720 next = rb_next(&cache->rb_node);
721 rb_erase(&cache->rb_node, root);
722 free(cache);
723 }
724 pthread_mutex_unlock(&dso->lock);
725 }
726
727 static struct dso_cache *dso_cache__find(struct dso *dso, u64 offset)
728 {
729 const struct rb_root *root = &dso->data.cache;
730 struct rb_node * const *p = &root->rb_node;
731 const struct rb_node *parent = NULL;
732 struct dso_cache *cache;
733
734 while (*p != NULL) {
735 u64 end;
736
737 parent = *p;
738 cache = rb_entry(parent, struct dso_cache, rb_node);
739 end = cache->offset + DSO__DATA_CACHE_SIZE;
740
741 if (offset < cache->offset)
742 p = &(*p)->rb_left;
743 else if (offset >= end)
744 p = &(*p)->rb_right;
745 else
746 return cache;
747 }
748
749 return NULL;
750 }
751
752 static struct dso_cache *
753 dso_cache__insert(struct dso *dso, struct dso_cache *new)
754 {
755 struct rb_root *root = &dso->data.cache;
756 struct rb_node **p = &root->rb_node;
757 struct rb_node *parent = NULL;
758 struct dso_cache *cache;
759 u64 offset = new->offset;
760
761 pthread_mutex_lock(&dso->lock);
762 while (*p != NULL) {
763 u64 end;
764
765 parent = *p;
766 cache = rb_entry(parent, struct dso_cache, rb_node);
767 end = cache->offset + DSO__DATA_CACHE_SIZE;
768
769 if (offset < cache->offset)
770 p = &(*p)->rb_left;
771 else if (offset >= end)
772 p = &(*p)->rb_right;
773 else
774 goto out;
775 }
776
777 rb_link_node(&new->rb_node, parent, p);
778 rb_insert_color(&new->rb_node, root);
779
780 cache = NULL;
781 out:
782 pthread_mutex_unlock(&dso->lock);
783 return cache;
784 }
785
786 static ssize_t
787 dso_cache__memcpy(struct dso_cache *cache, u64 offset,
788 u8 *data, u64 size)
789 {
790 u64 cache_offset = offset - cache->offset;
791 u64 cache_size = min(cache->size - cache_offset, size);
792
793 memcpy(data, cache->data + cache_offset, cache_size);
794 return cache_size;
795 }
796
797 static ssize_t
798 dso_cache__read(struct dso *dso, struct machine *machine,
799 u64 offset, u8 *data, ssize_t size)
800 {
801 struct dso_cache *cache;
802 struct dso_cache *old;
803 ssize_t ret;
804
805 do {
806 u64 cache_offset;
807
808 cache = zalloc(sizeof(*cache) + DSO__DATA_CACHE_SIZE);
809 if (!cache)
810 return -ENOMEM;
811
812 pthread_mutex_lock(&dso__data_open_lock);
813
814 /*
815 * dso->data.fd might be closed if other thread opened another
816 * file (dso) due to open file limit (RLIMIT_NOFILE).
817 */
818 try_to_open_dso(dso, machine);
819
820 if (dso->data.fd < 0) {
821 ret = -errno;
822 dso->data.status = DSO_DATA_STATUS_ERROR;
823 break;
824 }
825
826 cache_offset = offset & DSO__DATA_CACHE_MASK;
827
828 ret = pread(dso->data.fd, cache->data, DSO__DATA_CACHE_SIZE, cache_offset);
829 if (ret <= 0)
830 break;
831
832 cache->offset = cache_offset;
833 cache->size = ret;
834 } while (0);
835
836 pthread_mutex_unlock(&dso__data_open_lock);
837
838 if (ret > 0) {
839 old = dso_cache__insert(dso, cache);
840 if (old) {
841 /* we lose the race */
842 free(cache);
843 cache = old;
844 }
845
846 ret = dso_cache__memcpy(cache, offset, data, size);
847 }
848
849 if (ret <= 0)
850 free(cache);
851
852 return ret;
853 }
854
855 static ssize_t dso_cache_read(struct dso *dso, struct machine *machine,
856 u64 offset, u8 *data, ssize_t size)
857 {
858 struct dso_cache *cache;
859
860 cache = dso_cache__find(dso, offset);
861 if (cache)
862 return dso_cache__memcpy(cache, offset, data, size);
863 else
864 return dso_cache__read(dso, machine, offset, data, size);
865 }
866
867 /*
868 * Reads and caches dso data DSO__DATA_CACHE_SIZE size chunks
869 * in the rb_tree. Any read to already cached data is served
870 * by cached data.
871 */
872 static ssize_t cached_read(struct dso *dso, struct machine *machine,
873 u64 offset, u8 *data, ssize_t size)
874 {
875 ssize_t r = 0;
876 u8 *p = data;
877
878 do {
879 ssize_t ret;
880
881 ret = dso_cache_read(dso, machine, offset, p, size);
882 if (ret < 0)
883 return ret;
884
885 /* Reached EOF, return what we have. */
886 if (!ret)
887 break;
888
889 BUG_ON(ret > size);
890
891 r += ret;
892 p += ret;
893 offset += ret;
894 size -= ret;
895
896 } while (size);
897
898 return r;
899 }
900
901 static int data_file_size(struct dso *dso, struct machine *machine)
902 {
903 int ret = 0;
904 struct stat st;
905 char sbuf[STRERR_BUFSIZE];
906
907 if (dso->data.file_size)
908 return 0;
909
910 if (dso->data.status == DSO_DATA_STATUS_ERROR)
911 return -1;
912
913 pthread_mutex_lock(&dso__data_open_lock);
914
915 /*
916 * dso->data.fd might be closed if other thread opened another
917 * file (dso) due to open file limit (RLIMIT_NOFILE).
918 */
919 try_to_open_dso(dso, machine);
920
921 if (dso->data.fd < 0) {
922 ret = -errno;
923 dso->data.status = DSO_DATA_STATUS_ERROR;
924 goto out;
925 }
926
927 if (fstat(dso->data.fd, &st) < 0) {
928 ret = -errno;
929 pr_err("dso cache fstat failed: %s\n",
930 str_error_r(errno, sbuf, sizeof(sbuf)));
931 dso->data.status = DSO_DATA_STATUS_ERROR;
932 goto out;
933 }
934 dso->data.file_size = st.st_size;
935
936 out:
937 pthread_mutex_unlock(&dso__data_open_lock);
938 return ret;
939 }
940
941 /**
942 * dso__data_size - Return dso data size
943 * @dso: dso object
944 * @machine: machine object
945 *
946 * Return: dso data size
947 */
948 off_t dso__data_size(struct dso *dso, struct machine *machine)
949 {
950 if (data_file_size(dso, machine))
951 return -1;
952
953 /* For now just estimate dso data size is close to file size */
954 return dso->data.file_size;
955 }
956
957 static ssize_t data_read_offset(struct dso *dso, struct machine *machine,
958 u64 offset, u8 *data, ssize_t size)
959 {
960 if (data_file_size(dso, machine))
961 return -1;
962
963 /* Check the offset sanity. */
964 if (offset > dso->data.file_size)
965 return -1;
966
967 if (offset + size < offset)
968 return -1;
969
970 return cached_read(dso, machine, offset, data, size);
971 }
972
973 /**
974 * dso__data_read_offset - Read data from dso file offset
975 * @dso: dso object
976 * @machine: machine object
977 * @offset: file offset
978 * @data: buffer to store data
979 * @size: size of the @data buffer
980 *
981 * External interface to read data from dso file offset. Open
982 * dso data file and use cached_read to get the data.
983 */
984 ssize_t dso__data_read_offset(struct dso *dso, struct machine *machine,
985 u64 offset, u8 *data, ssize_t size)
986 {
987 if (dso->data.status == DSO_DATA_STATUS_ERROR)
988 return -1;
989
990 return data_read_offset(dso, machine, offset, data, size);
991 }
992
993 /**
994 * dso__data_read_addr - Read data from dso address
995 * @dso: dso object
996 * @machine: machine object
997 * @add: virtual memory address
998 * @data: buffer to store data
999 * @size: size of the @data buffer
1000 *
1001 * External interface to read data from dso address.
1002 */
1003 ssize_t dso__data_read_addr(struct dso *dso, struct map *map,
1004 struct machine *machine, u64 addr,
1005 u8 *data, ssize_t size)
1006 {
1007 u64 offset = map->map_ip(map, addr);
1008 return dso__data_read_offset(dso, machine, offset, data, size);
1009 }
1010
1011 struct map *dso__new_map(const char *name)
1012 {
1013 struct map *map = NULL;
1014 struct dso *dso = dso__new(name);
1015
1016 if (dso)
1017 map = map__new2(0, dso, MAP__FUNCTION);
1018
1019 return map;
1020 }
1021
1022 struct dso *machine__findnew_kernel(struct machine *machine, const char *name,
1023 const char *short_name, int dso_type)
1024 {
1025 /*
1026 * The kernel dso could be created by build_id processing.
1027 */
1028 struct dso *dso = machine__findnew_dso(machine, name);
1029
1030 /*
1031 * We need to run this in all cases, since during the build_id
1032 * processing we had no idea this was the kernel dso.
1033 */
1034 if (dso != NULL) {
1035 dso__set_short_name(dso, short_name, false);
1036 dso->kernel = dso_type;
1037 }
1038
1039 return dso;
1040 }
1041
1042 /*
1043 * Find a matching entry and/or link current entry to RB tree.
1044 * Either one of the dso or name parameter must be non-NULL or the
1045 * function will not work.
1046 */
1047 static struct dso *__dso__findlink_by_longname(struct rb_root *root,
1048 struct dso *dso, const char *name)
1049 {
1050 struct rb_node **p = &root->rb_node;
1051 struct rb_node *parent = NULL;
1052
1053 if (!name)
1054 name = dso->long_name;
1055 /*
1056 * Find node with the matching name
1057 */
1058 while (*p) {
1059 struct dso *this = rb_entry(*p, struct dso, rb_node);
1060 int rc = strcmp(name, this->long_name);
1061
1062 parent = *p;
1063 if (rc == 0) {
1064 /*
1065 * In case the new DSO is a duplicate of an existing
1066 * one, print a one-time warning & put the new entry
1067 * at the end of the list of duplicates.
1068 */
1069 if (!dso || (dso == this))
1070 return this; /* Find matching dso */
1071 /*
1072 * The core kernel DSOs may have duplicated long name.
1073 * In this case, the short name should be different.
1074 * Comparing the short names to differentiate the DSOs.
1075 */
1076 rc = strcmp(dso->short_name, this->short_name);
1077 if (rc == 0) {
1078 pr_err("Duplicated dso name: %s\n", name);
1079 return NULL;
1080 }
1081 }
1082 if (rc < 0)
1083 p = &parent->rb_left;
1084 else
1085 p = &parent->rb_right;
1086 }
1087 if (dso) {
1088 /* Add new node and rebalance tree */
1089 rb_link_node(&dso->rb_node, parent, p);
1090 rb_insert_color(&dso->rb_node, root);
1091 dso->root = root;
1092 }
1093 return NULL;
1094 }
1095
1096 static inline struct dso *__dso__find_by_longname(struct rb_root *root,
1097 const char *name)
1098 {
1099 return __dso__findlink_by_longname(root, NULL, name);
1100 }
1101
1102 void dso__set_long_name(struct dso *dso, const char *name, bool name_allocated)
1103 {
1104 struct rb_root *root = dso->root;
1105
1106 if (name == NULL)
1107 return;
1108
1109 if (dso->long_name_allocated)
1110 free((char *)dso->long_name);
1111
1112 if (root) {
1113 rb_erase(&dso->rb_node, root);
1114 /*
1115 * __dso__findlink_by_longname() isn't guaranteed to add it
1116 * back, so a clean removal is required here.
1117 */
1118 RB_CLEAR_NODE(&dso->rb_node);
1119 dso->root = NULL;
1120 }
1121
1122 dso->long_name = name;
1123 dso->long_name_len = strlen(name);
1124 dso->long_name_allocated = name_allocated;
1125
1126 if (root)
1127 __dso__findlink_by_longname(root, dso, NULL);
1128 }
1129
1130 void dso__set_short_name(struct dso *dso, const char *name, bool name_allocated)
1131 {
1132 if (name == NULL)
1133 return;
1134
1135 if (dso->short_name_allocated)
1136 free((char *)dso->short_name);
1137
1138 dso->short_name = name;
1139 dso->short_name_len = strlen(name);
1140 dso->short_name_allocated = name_allocated;
1141 }
1142
1143 static void dso__set_basename(struct dso *dso)
1144 {
1145 /*
1146 * basename() may modify path buffer, so we must pass
1147 * a copy.
1148 */
1149 char *base, *lname = strdup(dso->long_name);
1150
1151 if (!lname)
1152 return;
1153
1154 /*
1155 * basename() may return a pointer to internal
1156 * storage which is reused in subsequent calls
1157 * so copy the result.
1158 */
1159 base = strdup(basename(lname));
1160
1161 free(lname);
1162
1163 if (!base)
1164 return;
1165
1166 dso__set_short_name(dso, base, true);
1167 }
1168
1169 int dso__name_len(const struct dso *dso)
1170 {
1171 if (!dso)
1172 return strlen("[unknown]");
1173 if (verbose > 0)
1174 return dso->long_name_len;
1175
1176 return dso->short_name_len;
1177 }
1178
1179 bool dso__loaded(const struct dso *dso, enum map_type type)
1180 {
1181 return dso->loaded & (1 << type);
1182 }
1183
1184 bool dso__sorted_by_name(const struct dso *dso, enum map_type type)
1185 {
1186 return dso->sorted_by_name & (1 << type);
1187 }
1188
1189 void dso__set_sorted_by_name(struct dso *dso, enum map_type type)
1190 {
1191 dso->sorted_by_name |= (1 << type);
1192 }
1193
1194 struct dso *dso__new(const char *name)
1195 {
1196 struct dso *dso = calloc(1, sizeof(*dso) + strlen(name) + 1);
1197
1198 if (dso != NULL) {
1199 int i;
1200 strcpy(dso->name, name);
1201 dso__set_long_name(dso, dso->name, false);
1202 dso__set_short_name(dso, dso->name, false);
1203 for (i = 0; i < MAP__NR_TYPES; ++i)
1204 dso->symbols[i] = dso->symbol_names[i] = RB_ROOT;
1205 dso->data.cache = RB_ROOT;
1206 dso->inlined_nodes = RB_ROOT;
1207 dso->srclines = RB_ROOT;
1208 dso->data.fd = -1;
1209 dso->data.status = DSO_DATA_STATUS_UNKNOWN;
1210 dso->symtab_type = DSO_BINARY_TYPE__NOT_FOUND;
1211 dso->binary_type = DSO_BINARY_TYPE__NOT_FOUND;
1212 dso->is_64_bit = (sizeof(void *) == 8);
1213 dso->loaded = 0;
1214 dso->rel = 0;
1215 dso->sorted_by_name = 0;
1216 dso->has_build_id = 0;
1217 dso->has_srcline = 1;
1218 dso->a2l_fails = 1;
1219 dso->kernel = DSO_TYPE_USER;
1220 dso->needs_swap = DSO_SWAP__UNSET;
1221 RB_CLEAR_NODE(&dso->rb_node);
1222 dso->root = NULL;
1223 INIT_LIST_HEAD(&dso->node);
1224 INIT_LIST_HEAD(&dso->data.open_entry);
1225 pthread_mutex_init(&dso->lock, NULL);
1226 refcount_set(&dso->refcnt, 1);
1227 }
1228
1229 return dso;
1230 }
1231
1232 void dso__delete(struct dso *dso)
1233 {
1234 int i;
1235
1236 if (!RB_EMPTY_NODE(&dso->rb_node))
1237 pr_err("DSO %s is still in rbtree when being deleted!\n",
1238 dso->long_name);
1239
1240 /* free inlines first, as they reference symbols */
1241 inlines__tree_delete(&dso->inlined_nodes);
1242 srcline__tree_delete(&dso->srclines);
1243 for (i = 0; i < MAP__NR_TYPES; ++i)
1244 symbols__delete(&dso->symbols[i]);
1245
1246 if (dso->short_name_allocated) {
1247 zfree((char **)&dso->short_name);
1248 dso->short_name_allocated = false;
1249 }
1250
1251 if (dso->long_name_allocated) {
1252 zfree((char **)&dso->long_name);
1253 dso->long_name_allocated = false;
1254 }
1255
1256 dso__data_close(dso);
1257 auxtrace_cache__free(dso->auxtrace_cache);
1258 dso_cache__free(dso);
1259 dso__free_a2l(dso);
1260 zfree(&dso->symsrc_filename);
1261 nsinfo__zput(dso->nsinfo);
1262 pthread_mutex_destroy(&dso->lock);
1263 free(dso);
1264 }
1265
1266 struct dso *dso__get(struct dso *dso)
1267 {
1268 if (dso)
1269 refcount_inc(&dso->refcnt);
1270 return dso;
1271 }
1272
1273 void dso__put(struct dso *dso)
1274 {
1275 if (dso && refcount_dec_and_test(&dso->refcnt))
1276 dso__delete(dso);
1277 }
1278
1279 void dso__set_build_id(struct dso *dso, void *build_id)
1280 {
1281 memcpy(dso->build_id, build_id, sizeof(dso->build_id));
1282 dso->has_build_id = 1;
1283 }
1284
1285 bool dso__build_id_equal(const struct dso *dso, u8 *build_id)
1286 {
1287 return memcmp(dso->build_id, build_id, sizeof(dso->build_id)) == 0;
1288 }
1289
1290 void dso__read_running_kernel_build_id(struct dso *dso, struct machine *machine)
1291 {
1292 char path[PATH_MAX];
1293
1294 if (machine__is_default_guest(machine))
1295 return;
1296 sprintf(path, "%s/sys/kernel/notes", machine->root_dir);
1297 if (sysfs__read_build_id(path, dso->build_id,
1298 sizeof(dso->build_id)) == 0)
1299 dso->has_build_id = true;
1300 }
1301
1302 int dso__kernel_module_get_build_id(struct dso *dso,
1303 const char *root_dir)
1304 {
1305 char filename[PATH_MAX];
1306 /*
1307 * kernel module short names are of the form "[module]" and
1308 * we need just "module" here.
1309 */
1310 const char *name = dso->short_name + 1;
1311
1312 snprintf(filename, sizeof(filename),
1313 "%s/sys/module/%.*s/notes/.note.gnu.build-id",
1314 root_dir, (int)strlen(name) - 1, name);
1315
1316 if (sysfs__read_build_id(filename, dso->build_id,
1317 sizeof(dso->build_id)) == 0)
1318 dso->has_build_id = true;
1319
1320 return 0;
1321 }
1322
1323 bool __dsos__read_build_ids(struct list_head *head, bool with_hits)
1324 {
1325 bool have_build_id = false;
1326 struct dso *pos;
1327 struct nscookie nsc;
1328
1329 list_for_each_entry(pos, head, node) {
1330 if (with_hits && !pos->hit && !dso__is_vdso(pos))
1331 continue;
1332 if (pos->has_build_id) {
1333 have_build_id = true;
1334 continue;
1335 }
1336 nsinfo__mountns_enter(pos->nsinfo, &nsc);
1337 if (filename__read_build_id(pos->long_name, pos->build_id,
1338 sizeof(pos->build_id)) > 0) {
1339 have_build_id = true;
1340 pos->has_build_id = true;
1341 }
1342 nsinfo__mountns_exit(&nsc);
1343 }
1344
1345 return have_build_id;
1346 }
1347
1348 void __dsos__add(struct dsos *dsos, struct dso *dso)
1349 {
1350 list_add_tail(&dso->node, &dsos->head);
1351 __dso__findlink_by_longname(&dsos->root, dso, NULL);
1352 /*
1353 * It is now in the linked list, grab a reference, then garbage collect
1354 * this when needing memory, by looking at LRU dso instances in the
1355 * list with atomic_read(&dso->refcnt) == 1, i.e. no references
1356 * anywhere besides the one for the list, do, under a lock for the
1357 * list: remove it from the list, then a dso__put(), that probably will
1358 * be the last and will then call dso__delete(), end of life.
1359 *
1360 * That, or at the end of the 'struct machine' lifetime, when all
1361 * 'struct dso' instances will be removed from the list, in
1362 * dsos__exit(), if they have no other reference from some other data
1363 * structure.
1364 *
1365 * E.g.: after processing a 'perf.data' file and storing references
1366 * to objects instantiated while processing events, we will have
1367 * references to the 'thread', 'map', 'dso' structs all from 'struct
1368 * hist_entry' instances, but we may not need anything not referenced,
1369 * so we might as well call machines__exit()/machines__delete() and
1370 * garbage collect it.
1371 */
1372 dso__get(dso);
1373 }
1374
1375 void dsos__add(struct dsos *dsos, struct dso *dso)
1376 {
1377 down_write(&dsos->lock);
1378 __dsos__add(dsos, dso);
1379 up_write(&dsos->lock);
1380 }
1381
1382 struct dso *__dsos__find(struct dsos *dsos, const char *name, bool cmp_short)
1383 {
1384 struct dso *pos;
1385
1386 if (cmp_short) {
1387 list_for_each_entry(pos, &dsos->head, node)
1388 if (strcmp(pos->short_name, name) == 0)
1389 return pos;
1390 return NULL;
1391 }
1392 return __dso__find_by_longname(&dsos->root, name);
1393 }
1394
1395 struct dso *dsos__find(struct dsos *dsos, const char *name, bool cmp_short)
1396 {
1397 struct dso *dso;
1398 down_read(&dsos->lock);
1399 dso = __dsos__find(dsos, name, cmp_short);
1400 up_read(&dsos->lock);
1401 return dso;
1402 }
1403
1404 struct dso *__dsos__addnew(struct dsos *dsos, const char *name)
1405 {
1406 struct dso *dso = dso__new(name);
1407
1408 if (dso != NULL) {
1409 __dsos__add(dsos, dso);
1410 dso__set_basename(dso);
1411 /* Put dso here because __dsos_add already got it */
1412 dso__put(dso);
1413 }
1414 return dso;
1415 }
1416
1417 struct dso *__dsos__findnew(struct dsos *dsos, const char *name)
1418 {
1419 struct dso *dso = __dsos__find(dsos, name, false);
1420
1421 return dso ? dso : __dsos__addnew(dsos, name);
1422 }
1423
1424 struct dso *dsos__findnew(struct dsos *dsos, const char *name)
1425 {
1426 struct dso *dso;
1427 down_write(&dsos->lock);
1428 dso = dso__get(__dsos__findnew(dsos, name));
1429 up_write(&dsos->lock);
1430 return dso;
1431 }
1432
1433 size_t __dsos__fprintf_buildid(struct list_head *head, FILE *fp,
1434 bool (skip)(struct dso *dso, int parm), int parm)
1435 {
1436 struct dso *pos;
1437 size_t ret = 0;
1438
1439 list_for_each_entry(pos, head, node) {
1440 if (skip && skip(pos, parm))
1441 continue;
1442 ret += dso__fprintf_buildid(pos, fp);
1443 ret += fprintf(fp, " %s\n", pos->long_name);
1444 }
1445 return ret;
1446 }
1447
1448 size_t __dsos__fprintf(struct list_head *head, FILE *fp)
1449 {
1450 struct dso *pos;
1451 size_t ret = 0;
1452
1453 list_for_each_entry(pos, head, node) {
1454 int i;
1455 for (i = 0; i < MAP__NR_TYPES; ++i)
1456 ret += dso__fprintf(pos, i, fp);
1457 }
1458
1459 return ret;
1460 }
1461
1462 size_t dso__fprintf_buildid(struct dso *dso, FILE *fp)
1463 {
1464 char sbuild_id[SBUILD_ID_SIZE];
1465
1466 build_id__sprintf(dso->build_id, sizeof(dso->build_id), sbuild_id);
1467 return fprintf(fp, "%s", sbuild_id);
1468 }
1469
1470 size_t dso__fprintf(struct dso *dso, enum map_type type, FILE *fp)
1471 {
1472 struct rb_node *nd;
1473 size_t ret = fprintf(fp, "dso: %s (", dso->short_name);
1474
1475 if (dso->short_name != dso->long_name)
1476 ret += fprintf(fp, "%s, ", dso->long_name);
1477 ret += fprintf(fp, "%s, %sloaded, ", map_type__name[type],
1478 dso__loaded(dso, type) ? "" : "NOT ");
1479 ret += dso__fprintf_buildid(dso, fp);
1480 ret += fprintf(fp, ")\n");
1481 for (nd = rb_first(&dso->symbols[type]); nd; nd = rb_next(nd)) {
1482 struct symbol *pos = rb_entry(nd, struct symbol, rb_node);
1483 ret += symbol__fprintf(pos, fp);
1484 }
1485
1486 return ret;
1487 }
1488
1489 enum dso_type dso__type(struct dso *dso, struct machine *machine)
1490 {
1491 int fd;
1492 enum dso_type type = DSO__TYPE_UNKNOWN;
1493
1494 fd = dso__data_get_fd(dso, machine);
1495 if (fd >= 0) {
1496 type = dso__type_fd(fd);
1497 dso__data_put_fd(dso);
1498 }
1499
1500 return type;
1501 }
1502
1503 int dso__strerror_load(struct dso *dso, char *buf, size_t buflen)
1504 {
1505 int idx, errnum = dso->load_errno;
1506 /*
1507 * This must have a same ordering as the enum dso_load_errno.
1508 */
1509 static const char *dso_load__error_str[] = {
1510 "Internal tools/perf/ library error",
1511 "Invalid ELF file",
1512 "Can not read build id",
1513 "Mismatching build id",
1514 "Decompression failure",
1515 };
1516
1517 BUG_ON(buflen == 0);
1518
1519 if (errnum >= 0) {
1520 const char *err = str_error_r(errnum, buf, buflen);
1521
1522 if (err != buf)
1523 scnprintf(buf, buflen, "%s", err);
1524
1525 return 0;
1526 }
1527
1528 if (errnum < __DSO_LOAD_ERRNO__START || errnum >= __DSO_LOAD_ERRNO__END)
1529 return -1;
1530
1531 idx = errnum - __DSO_LOAD_ERRNO__START;
1532 scnprintf(buf, buflen, "%s", dso_load__error_str[idx]);
1533 return 0;
1534 }
CRIS linux kernel tree