bfb055459670289b14ac184e8a241b07159cdd16
[safe/jmp/linux-2.6] / tools / perf / util / symbol.c
1 #include "util.h"
2 #include "../perf.h"
3 #include "sort.h"
4 #include "string.h"
5 #include "symbol.h"
6 #include "thread.h"
7
8 #include "debug.h"
9
10 #include <asm/bug.h>
11 #include <libelf.h>
12 #include <gelf.h>
13 #include <elf.h>
14 #include <limits.h>
15 #include <sys/utsname.h>
16
17 #ifndef NT_GNU_BUILD_ID
18 #define NT_GNU_BUILD_ID 3
19 #endif
20
21 enum dso_origin {
22         DSO__ORIG_KERNEL = 0,
23         DSO__ORIG_JAVA_JIT,
24         DSO__ORIG_BUILD_ID_CACHE,
25         DSO__ORIG_FEDORA,
26         DSO__ORIG_UBUNTU,
27         DSO__ORIG_BUILDID,
28         DSO__ORIG_DSO,
29         DSO__ORIG_KMODULE,
30         DSO__ORIG_NOT_FOUND,
31 };
32
33 static void dsos__add(struct list_head *head, struct dso *dso);
34 static struct map *map__new2(u64 start, struct dso *dso, enum map_type type);
35 static int dso__load_kernel_sym(struct dso *self, struct map *map,
36                                 symbol_filter_t filter);
37 static int vmlinux_path__nr_entries;
38 static char **vmlinux_path;
39
40 struct symbol_conf symbol_conf = {
41         .exclude_other    = true,
42         .use_modules      = true,
43         .try_vmlinux_path = true,
44 };
45
46 bool dso__loaded(const struct dso *self, enum map_type type)
47 {
48         return self->loaded & (1 << type);
49 }
50
51 bool dso__sorted_by_name(const struct dso *self, enum map_type type)
52 {
53         return self->sorted_by_name & (1 << type);
54 }
55
56 static void dso__set_sorted_by_name(struct dso *self, enum map_type type)
57 {
58         self->sorted_by_name |= (1 << type);
59 }
60
61 bool symbol_type__is_a(char symbol_type, enum map_type map_type)
62 {
63         switch (map_type) {
64         case MAP__FUNCTION:
65                 return symbol_type == 'T' || symbol_type == 'W';
66         case MAP__VARIABLE:
67                 return symbol_type == 'D' || symbol_type == 'd';
68         default:
69                 return false;
70         }
71 }
72
73 static void symbols__fixup_end(struct rb_root *self)
74 {
75         struct rb_node *nd, *prevnd = rb_first(self);
76         struct symbol *curr, *prev;
77
78         if (prevnd == NULL)
79                 return;
80
81         curr = rb_entry(prevnd, struct symbol, rb_node);
82
83         for (nd = rb_next(prevnd); nd; nd = rb_next(nd)) {
84                 prev = curr;
85                 curr = rb_entry(nd, struct symbol, rb_node);
86
87                 if (prev->end == prev->start)
88                         prev->end = curr->start - 1;
89         }
90
91         /* Last entry */
92         if (curr->end == curr->start)
93                 curr->end = roundup(curr->start, 4096);
94 }
95
96 static void __map_groups__fixup_end(struct map_groups *self, enum map_type type)
97 {
98         struct map *prev, *curr;
99         struct rb_node *nd, *prevnd = rb_first(&self->maps[type]);
100
101         if (prevnd == NULL)
102                 return;
103
104         curr = rb_entry(prevnd, struct map, rb_node);
105
106         for (nd = rb_next(prevnd); nd; nd = rb_next(nd)) {
107                 prev = curr;
108                 curr = rb_entry(nd, struct map, rb_node);
109                 prev->end = curr->start - 1;
110         }
111
112         /*
113          * We still haven't the actual symbols, so guess the
114          * last map final address.
115          */
116         curr->end = ~0UL;
117 }
118
119 static void map_groups__fixup_end(struct map_groups *self)
120 {
121         int i;
122         for (i = 0; i < MAP__NR_TYPES; ++i)
123                 __map_groups__fixup_end(self, i);
124 }
125
126 static struct symbol *symbol__new(u64 start, u64 len, const char *name)
127 {
128         size_t namelen = strlen(name) + 1;
129         struct symbol *self = zalloc(symbol_conf.priv_size +
130                                      sizeof(*self) + namelen);
131         if (self == NULL)
132                 return NULL;
133
134         if (symbol_conf.priv_size)
135                 self = ((void *)self) + symbol_conf.priv_size;
136
137         self->start = start;
138         self->end   = len ? start + len - 1 : start;
139
140         pr_debug3("%s: %s %#Lx-%#Lx\n", __func__, name, start, self->end);
141
142         memcpy(self->name, name, namelen);
143
144         return self;
145 }
146
147 static void symbol__delete(struct symbol *self)
148 {
149         free(((void *)self) - symbol_conf.priv_size);
150 }
151
152 static size_t symbol__fprintf(struct symbol *self, FILE *fp)
153 {
154         return fprintf(fp, " %llx-%llx %s\n",
155                        self->start, self->end, self->name);
156 }
157
158 void dso__set_long_name(struct dso *self, char *name)
159 {
160         if (name == NULL)
161                 return;
162         self->long_name = name;
163         self->long_name_len = strlen(name);
164 }
165
166 static void dso__set_basename(struct dso *self)
167 {
168         self->short_name = basename(self->long_name);
169 }
170
171 struct dso *dso__new(const char *name)
172 {
173         struct dso *self = zalloc(sizeof(*self) + strlen(name) + 1);
174
175         if (self != NULL) {
176                 int i;
177                 strcpy(self->name, name);
178                 dso__set_long_name(self, self->name);
179                 self->short_name = self->name;
180                 for (i = 0; i < MAP__NR_TYPES; ++i)
181                         self->symbols[i] = self->symbol_names[i] = RB_ROOT;
182                 self->slen_calculated = 0;
183                 self->origin = DSO__ORIG_NOT_FOUND;
184                 self->loaded = 0;
185                 self->sorted_by_name = 0;
186                 self->has_build_id = 0;
187         }
188
189         return self;
190 }
191
192 static void symbols__delete(struct rb_root *self)
193 {
194         struct symbol *pos;
195         struct rb_node *next = rb_first(self);
196
197         while (next) {
198                 pos = rb_entry(next, struct symbol, rb_node);
199                 next = rb_next(&pos->rb_node);
200                 rb_erase(&pos->rb_node, self);
201                 symbol__delete(pos);
202         }
203 }
204
205 void dso__delete(struct dso *self)
206 {
207         int i;
208         for (i = 0; i < MAP__NR_TYPES; ++i)
209                 symbols__delete(&self->symbols[i]);
210         if (self->long_name != self->name)
211                 free(self->long_name);
212         free(self);
213 }
214
215 void dso__set_build_id(struct dso *self, void *build_id)
216 {
217         memcpy(self->build_id, build_id, sizeof(self->build_id));
218         self->has_build_id = 1;
219 }
220
221 static void symbols__insert(struct rb_root *self, struct symbol *sym)
222 {
223         struct rb_node **p = &self->rb_node;
224         struct rb_node *parent = NULL;
225         const u64 ip = sym->start;
226         struct symbol *s;
227
228         while (*p != NULL) {
229                 parent = *p;
230                 s = rb_entry(parent, struct symbol, rb_node);
231                 if (ip < s->start)
232                         p = &(*p)->rb_left;
233                 else
234                         p = &(*p)->rb_right;
235         }
236         rb_link_node(&sym->rb_node, parent, p);
237         rb_insert_color(&sym->rb_node, self);
238 }
239
240 static struct symbol *symbols__find(struct rb_root *self, u64 ip)
241 {
242         struct rb_node *n;
243
244         if (self == NULL)
245                 return NULL;
246
247         n = self->rb_node;
248
249         while (n) {
250                 struct symbol *s = rb_entry(n, struct symbol, rb_node);
251
252                 if (ip < s->start)
253                         n = n->rb_left;
254                 else if (ip > s->end)
255                         n = n->rb_right;
256                 else
257                         return s;
258         }
259
260         return NULL;
261 }
262
263 struct symbol_name_rb_node {
264         struct rb_node  rb_node;
265         struct symbol   sym;
266 };
267
268 static void symbols__insert_by_name(struct rb_root *self, struct symbol *sym)
269 {
270         struct rb_node **p = &self->rb_node;
271         struct rb_node *parent = NULL;
272         struct symbol_name_rb_node *symn = ((void *)sym) - sizeof(*parent), *s;
273
274         while (*p != NULL) {
275                 parent = *p;
276                 s = rb_entry(parent, struct symbol_name_rb_node, rb_node);
277                 if (strcmp(sym->name, s->sym.name) < 0)
278                         p = &(*p)->rb_left;
279                 else
280                         p = &(*p)->rb_right;
281         }
282         rb_link_node(&symn->rb_node, parent, p);
283         rb_insert_color(&symn->rb_node, self);
284 }
285
286 static void symbols__sort_by_name(struct rb_root *self, struct rb_root *source)
287 {
288         struct rb_node *nd;
289
290         for (nd = rb_first(source); nd; nd = rb_next(nd)) {
291                 struct symbol *pos = rb_entry(nd, struct symbol, rb_node);
292                 symbols__insert_by_name(self, pos);
293         }
294 }
295
296 static struct symbol *symbols__find_by_name(struct rb_root *self, const char *name)
297 {
298         struct rb_node *n;
299
300         if (self == NULL)
301                 return NULL;
302
303         n = self->rb_node;
304
305         while (n) {
306                 struct symbol_name_rb_node *s;
307                 int cmp;
308
309                 s = rb_entry(n, struct symbol_name_rb_node, rb_node);
310                 cmp = strcmp(name, s->sym.name);
311
312                 if (cmp < 0)
313                         n = n->rb_left;
314                 else if (cmp > 0)
315                         n = n->rb_right;
316                 else
317                         return &s->sym;
318         }
319
320         return NULL;
321 }
322
323 struct symbol *dso__find_symbol(struct dso *self,
324                                 enum map_type type, u64 addr)
325 {
326         return symbols__find(&self->symbols[type], addr);
327 }
328
329 struct symbol *dso__find_symbol_by_name(struct dso *self, enum map_type type,
330                                         const char *name)
331 {
332         return symbols__find_by_name(&self->symbol_names[type], name);
333 }
334
335 void dso__sort_by_name(struct dso *self, enum map_type type)
336 {
337         dso__set_sorted_by_name(self, type);
338         return symbols__sort_by_name(&self->symbol_names[type],
339                                      &self->symbols[type]);
340 }
341
342 int build_id__sprintf(const u8 *self, int len, char *bf)
343 {
344         char *bid = bf;
345         const u8 *raw = self;
346         int i;
347
348         for (i = 0; i < len; ++i) {
349                 sprintf(bid, "%02x", *raw);
350                 ++raw;
351                 bid += 2;
352         }
353
354         return raw - self;
355 }
356
357 size_t dso__fprintf_buildid(struct dso *self, FILE *fp)
358 {
359         char sbuild_id[BUILD_ID_SIZE * 2 + 1];
360
361         build_id__sprintf(self->build_id, sizeof(self->build_id), sbuild_id);
362         return fprintf(fp, "%s", sbuild_id);
363 }
364
365 size_t dso__fprintf(struct dso *self, enum map_type type, FILE *fp)
366 {
367         struct rb_node *nd;
368         size_t ret = fprintf(fp, "dso: %s (", self->short_name);
369
370         ret += dso__fprintf_buildid(self, fp);
371         ret += fprintf(fp, ")\n");
372         for (nd = rb_first(&self->symbols[type]); nd; nd = rb_next(nd)) {
373                 struct symbol *pos = rb_entry(nd, struct symbol, rb_node);
374                 ret += symbol__fprintf(pos, fp);
375         }
376
377         return ret;
378 }
379
380 int kallsyms__parse(const char *filename, void *arg,
381                     int (*process_symbol)(void *arg, const char *name,
382                                                      char type, u64 start))
383 {
384         char *line = NULL;
385         size_t n;
386         int err = 0;
387         FILE *file = fopen(filename, "r");
388
389         if (file == NULL)
390                 goto out_failure;
391
392         while (!feof(file)) {
393                 u64 start;
394                 int line_len, len;
395                 char symbol_type;
396                 char *symbol_name;
397
398                 line_len = getline(&line, &n, file);
399                 if (line_len < 0)
400                         break;
401
402                 if (!line)
403                         goto out_failure;
404
405                 line[--line_len] = '\0'; /* \n */
406
407                 len = hex2u64(line, &start);
408
409                 len++;
410                 if (len + 2 >= line_len)
411                         continue;
412
413                 symbol_type = toupper(line[len]);
414                 symbol_name = line + len + 2;
415
416                 err = process_symbol(arg, symbol_name, symbol_type, start);
417                 if (err)
418                         break;
419         }
420
421         free(line);
422         fclose(file);
423         return err;
424
425 out_failure:
426         return -1;
427 }
428
429 struct process_kallsyms_args {
430         struct map *map;
431         struct dso *dso;
432 };
433
434 static int map__process_kallsym_symbol(void *arg, const char *name,
435                                        char type, u64 start)
436 {
437         struct symbol *sym;
438         struct process_kallsyms_args *a = arg;
439         struct rb_root *root = &a->dso->symbols[a->map->type];
440
441         if (!symbol_type__is_a(type, a->map->type))
442                 return 0;
443
444         /*
445          * Will fix up the end later, when we have all symbols sorted.
446          */
447         sym = symbol__new(start, 0, name);
448
449         if (sym == NULL)
450                 return -ENOMEM;
451         /*
452          * We will pass the symbols to the filter later, in
453          * map__split_kallsyms, when we have split the maps per module
454          */
455         symbols__insert(root, sym);
456         return 0;
457 }
458
459 /*
460  * Loads the function entries in /proc/kallsyms into kernel_map->dso,
461  * so that we can in the next step set the symbol ->end address and then
462  * call kernel_maps__split_kallsyms.
463  */
464 static int dso__load_all_kallsyms(struct dso *self, const char *filename,
465                                   struct map *map)
466 {
467         struct process_kallsyms_args args = { .map = map, .dso = self, };
468         return kallsyms__parse(filename, &args, map__process_kallsym_symbol);
469 }
470
471 /*
472  * Split the symbols into maps, making sure there are no overlaps, i.e. the
473  * kernel range is broken in several maps, named [kernel].N, as we don't have
474  * the original ELF section names vmlinux have.
475  */
476 static int dso__split_kallsyms(struct dso *self, struct map *map,
477                                symbol_filter_t filter)
478 {
479         struct map_groups *kmaps = map__kmap(map)->kmaps;
480         struct map *curr_map = map;
481         struct symbol *pos;
482         int count = 0;
483         struct rb_root *root = &self->symbols[map->type];
484         struct rb_node *next = rb_first(root);
485         int kernel_range = 0;
486
487         while (next) {
488                 char *module;
489
490                 pos = rb_entry(next, struct symbol, rb_node);
491                 next = rb_next(&pos->rb_node);
492
493                 module = strchr(pos->name, '\t');
494                 if (module) {
495                         if (!symbol_conf.use_modules)
496                                 goto discard_symbol;
497
498                         *module++ = '\0';
499
500                         if (strcmp(curr_map->dso->short_name, module)) {
501                                 curr_map = map_groups__find_by_name(kmaps, map->type, module);
502                                 if (curr_map == NULL) {
503                                         pr_debug("/proc/{kallsyms,modules} "
504                                                  "inconsistency while looking "
505                                                  "for \"%s\" module!\n", module);
506                                         return -1;
507                                 }
508
509                                 if (curr_map->dso->loaded)
510                                         goto discard_symbol;
511                         }
512                         /*
513                          * So that we look just like we get from .ko files,
514                          * i.e. not prelinked, relative to map->start.
515                          */
516                         pos->start = curr_map->map_ip(curr_map, pos->start);
517                         pos->end   = curr_map->map_ip(curr_map, pos->end);
518                 } else if (curr_map != map) {
519                         char dso_name[PATH_MAX];
520                         struct dso *dso;
521
522                         snprintf(dso_name, sizeof(dso_name), "[kernel].%d",
523                                  kernel_range++);
524
525                         dso = dso__new(dso_name);
526                         if (dso == NULL)
527                                 return -1;
528
529                         curr_map = map__new2(pos->start, dso, map->type);
530                         if (map == NULL) {
531                                 dso__delete(dso);
532                                 return -1;
533                         }
534
535                         curr_map->map_ip = curr_map->unmap_ip = identity__map_ip;
536                         map_groups__insert(kmaps, curr_map);
537                         ++kernel_range;
538                 }
539
540                 if (filter && filter(curr_map, pos)) {
541 discard_symbol:         rb_erase(&pos->rb_node, root);
542                         symbol__delete(pos);
543                 } else {
544                         if (curr_map != map) {
545                                 rb_erase(&pos->rb_node, root);
546                                 symbols__insert(&curr_map->dso->symbols[curr_map->type], pos);
547                         }
548                         count++;
549                 }
550         }
551
552         return count;
553 }
554
555 int dso__load_kallsyms(struct dso *self, const char *filename,
556                        struct map *map, symbol_filter_t filter)
557 {
558         if (dso__load_all_kallsyms(self, filename, map) < 0)
559                 return -1;
560
561         symbols__fixup_end(&self->symbols[map->type]);
562         self->origin = DSO__ORIG_KERNEL;
563
564         return dso__split_kallsyms(self, map, filter);
565 }
566
567 static int dso__load_perf_map(struct dso *self, struct map *map,
568                               symbol_filter_t filter)
569 {
570         char *line = NULL;
571         size_t n;
572         FILE *file;
573         int nr_syms = 0;
574
575         file = fopen(self->long_name, "r");
576         if (file == NULL)
577                 goto out_failure;
578
579         while (!feof(file)) {
580                 u64 start, size;
581                 struct symbol *sym;
582                 int line_len, len;
583
584                 line_len = getline(&line, &n, file);
585                 if (line_len < 0)
586                         break;
587
588                 if (!line)
589                         goto out_failure;
590
591                 line[--line_len] = '\0'; /* \n */
592
593                 len = hex2u64(line, &start);
594
595                 len++;
596                 if (len + 2 >= line_len)
597                         continue;
598
599                 len += hex2u64(line + len, &size);
600
601                 len++;
602                 if (len + 2 >= line_len)
603                         continue;
604
605                 sym = symbol__new(start, size, line + len);
606
607                 if (sym == NULL)
608                         goto out_delete_line;
609
610                 if (filter && filter(map, sym))
611                         symbol__delete(sym);
612                 else {
613                         symbols__insert(&self->symbols[map->type], sym);
614                         nr_syms++;
615                 }
616         }
617
618         free(line);
619         fclose(file);
620
621         return nr_syms;
622
623 out_delete_line:
624         free(line);
625 out_failure:
626         return -1;
627 }
628
629 /**
630  * elf_symtab__for_each_symbol - iterate thru all the symbols
631  *
632  * @self: struct elf_symtab instance to iterate
633  * @idx: uint32_t idx
634  * @sym: GElf_Sym iterator
635  */
636 #define elf_symtab__for_each_symbol(syms, nr_syms, idx, sym) \
637         for (idx = 0, gelf_getsym(syms, idx, &sym);\
638              idx < nr_syms; \
639              idx++, gelf_getsym(syms, idx, &sym))
640
641 static inline uint8_t elf_sym__type(const GElf_Sym *sym)
642 {
643         return GELF_ST_TYPE(sym->st_info);
644 }
645
646 static inline int elf_sym__is_function(const GElf_Sym *sym)
647 {
648         return elf_sym__type(sym) == STT_FUNC &&
649                sym->st_name != 0 &&
650                sym->st_shndx != SHN_UNDEF;
651 }
652
653 static inline bool elf_sym__is_object(const GElf_Sym *sym)
654 {
655         return elf_sym__type(sym) == STT_OBJECT &&
656                 sym->st_name != 0 &&
657                 sym->st_shndx != SHN_UNDEF;
658 }
659
660 static inline int elf_sym__is_label(const GElf_Sym *sym)
661 {
662         return elf_sym__type(sym) == STT_NOTYPE &&
663                 sym->st_name != 0 &&
664                 sym->st_shndx != SHN_UNDEF &&
665                 sym->st_shndx != SHN_ABS;
666 }
667
668 static inline const char *elf_sec__name(const GElf_Shdr *shdr,
669                                         const Elf_Data *secstrs)
670 {
671         return secstrs->d_buf + shdr->sh_name;
672 }
673
674 static inline int elf_sec__is_text(const GElf_Shdr *shdr,
675                                         const Elf_Data *secstrs)
676 {
677         return strstr(elf_sec__name(shdr, secstrs), "text") != NULL;
678 }
679
680 static inline bool elf_sec__is_data(const GElf_Shdr *shdr,
681                                     const Elf_Data *secstrs)
682 {
683         return strstr(elf_sec__name(shdr, secstrs), "data") != NULL;
684 }
685
686 static inline const char *elf_sym__name(const GElf_Sym *sym,
687                                         const Elf_Data *symstrs)
688 {
689         return symstrs->d_buf + sym->st_name;
690 }
691
692 static Elf_Scn *elf_section_by_name(Elf *elf, GElf_Ehdr *ep,
693                                     GElf_Shdr *shp, const char *name,
694                                     size_t *idx)
695 {
696         Elf_Scn *sec = NULL;
697         size_t cnt = 1;
698
699         while ((sec = elf_nextscn(elf, sec)) != NULL) {
700                 char *str;
701
702                 gelf_getshdr(sec, shp);
703                 str = elf_strptr(elf, ep->e_shstrndx, shp->sh_name);
704                 if (!strcmp(name, str)) {
705                         if (idx)
706                                 *idx = cnt;
707                         break;
708                 }
709                 ++cnt;
710         }
711
712         return sec;
713 }
714
715 #define elf_section__for_each_rel(reldata, pos, pos_mem, idx, nr_entries) \
716         for (idx = 0, pos = gelf_getrel(reldata, 0, &pos_mem); \
717              idx < nr_entries; \
718              ++idx, pos = gelf_getrel(reldata, idx, &pos_mem))
719
720 #define elf_section__for_each_rela(reldata, pos, pos_mem, idx, nr_entries) \
721         for (idx = 0, pos = gelf_getrela(reldata, 0, &pos_mem); \
722              idx < nr_entries; \
723              ++idx, pos = gelf_getrela(reldata, idx, &pos_mem))
724
725 /*
726  * We need to check if we have a .dynsym, so that we can handle the
727  * .plt, synthesizing its symbols, that aren't on the symtabs (be it
728  * .dynsym or .symtab).
729  * And always look at the original dso, not at debuginfo packages, that
730  * have the PLT data stripped out (shdr_rel_plt.sh_type == SHT_NOBITS).
731  */
732 static int dso__synthesize_plt_symbols(struct  dso *self, struct map *map,
733                                        symbol_filter_t filter)
734 {
735         uint32_t nr_rel_entries, idx;
736         GElf_Sym sym;
737         u64 plt_offset;
738         GElf_Shdr shdr_plt;
739         struct symbol *f;
740         GElf_Shdr shdr_rel_plt, shdr_dynsym;
741         Elf_Data *reldata, *syms, *symstrs;
742         Elf_Scn *scn_plt_rel, *scn_symstrs, *scn_dynsym;
743         size_t dynsym_idx;
744         GElf_Ehdr ehdr;
745         char sympltname[1024];
746         Elf *elf;
747         int nr = 0, symidx, fd, err = 0;
748
749         fd = open(self->long_name, O_RDONLY);
750         if (fd < 0)
751                 goto out;
752
753         elf = elf_begin(fd, PERF_ELF_C_READ_MMAP, NULL);
754         if (elf == NULL)
755                 goto out_close;
756
757         if (gelf_getehdr(elf, &ehdr) == NULL)
758                 goto out_elf_end;
759
760         scn_dynsym = elf_section_by_name(elf, &ehdr, &shdr_dynsym,
761                                          ".dynsym", &dynsym_idx);
762         if (scn_dynsym == NULL)
763                 goto out_elf_end;
764
765         scn_plt_rel = elf_section_by_name(elf, &ehdr, &shdr_rel_plt,
766                                           ".rela.plt", NULL);
767         if (scn_plt_rel == NULL) {
768                 scn_plt_rel = elf_section_by_name(elf, &ehdr, &shdr_rel_plt,
769                                                   ".rel.plt", NULL);
770                 if (scn_plt_rel == NULL)
771                         goto out_elf_end;
772         }
773
774         err = -1;
775
776         if (shdr_rel_plt.sh_link != dynsym_idx)
777                 goto out_elf_end;
778
779         if (elf_section_by_name(elf, &ehdr, &shdr_plt, ".plt", NULL) == NULL)
780                 goto out_elf_end;
781
782         /*
783          * Fetch the relocation section to find the idxes to the GOT
784          * and the symbols in the .dynsym they refer to.
785          */
786         reldata = elf_getdata(scn_plt_rel, NULL);
787         if (reldata == NULL)
788                 goto out_elf_end;
789
790         syms = elf_getdata(scn_dynsym, NULL);
791         if (syms == NULL)
792                 goto out_elf_end;
793
794         scn_symstrs = elf_getscn(elf, shdr_dynsym.sh_link);
795         if (scn_symstrs == NULL)
796                 goto out_elf_end;
797
798         symstrs = elf_getdata(scn_symstrs, NULL);
799         if (symstrs == NULL)
800                 goto out_elf_end;
801
802         nr_rel_entries = shdr_rel_plt.sh_size / shdr_rel_plt.sh_entsize;
803         plt_offset = shdr_plt.sh_offset;
804
805         if (shdr_rel_plt.sh_type == SHT_RELA) {
806                 GElf_Rela pos_mem, *pos;
807
808                 elf_section__for_each_rela(reldata, pos, pos_mem, idx,
809                                            nr_rel_entries) {
810                         symidx = GELF_R_SYM(pos->r_info);
811                         plt_offset += shdr_plt.sh_entsize;
812                         gelf_getsym(syms, symidx, &sym);
813                         snprintf(sympltname, sizeof(sympltname),
814                                  "%s@plt", elf_sym__name(&sym, symstrs));
815
816                         f = symbol__new(plt_offset, shdr_plt.sh_entsize,
817                                         sympltname);
818                         if (!f)
819                                 goto out_elf_end;
820
821                         if (filter && filter(map, f))
822                                 symbol__delete(f);
823                         else {
824                                 symbols__insert(&self->symbols[map->type], f);
825                                 ++nr;
826                         }
827                 }
828         } else if (shdr_rel_plt.sh_type == SHT_REL) {
829                 GElf_Rel pos_mem, *pos;
830                 elf_section__for_each_rel(reldata, pos, pos_mem, idx,
831                                           nr_rel_entries) {
832                         symidx = GELF_R_SYM(pos->r_info);
833                         plt_offset += shdr_plt.sh_entsize;
834                         gelf_getsym(syms, symidx, &sym);
835                         snprintf(sympltname, sizeof(sympltname),
836                                  "%s@plt", elf_sym__name(&sym, symstrs));
837
838                         f = symbol__new(plt_offset, shdr_plt.sh_entsize,
839                                         sympltname);
840                         if (!f)
841                                 goto out_elf_end;
842
843                         if (filter && filter(map, f))
844                                 symbol__delete(f);
845                         else {
846                                 symbols__insert(&self->symbols[map->type], f);
847                                 ++nr;
848                         }
849                 }
850         }
851
852         err = 0;
853 out_elf_end:
854         elf_end(elf);
855 out_close:
856         close(fd);
857
858         if (err == 0)
859                 return nr;
860 out:
861         pr_warning("%s: problems reading %s PLT info.\n",
862                    __func__, self->long_name);
863         return 0;
864 }
865
866 static bool elf_sym__is_a(GElf_Sym *self, enum map_type type)
867 {
868         switch (type) {
869         case MAP__FUNCTION:
870                 return elf_sym__is_function(self);
871         case MAP__VARIABLE:
872                 return elf_sym__is_object(self);
873         default:
874                 return false;
875         }
876 }
877
878 static bool elf_sec__is_a(GElf_Shdr *self, Elf_Data *secstrs, enum map_type type)
879 {
880         switch (type) {
881         case MAP__FUNCTION:
882                 return elf_sec__is_text(self, secstrs);
883         case MAP__VARIABLE:
884                 return elf_sec__is_data(self, secstrs);
885         default:
886                 return false;
887         }
888 }
889
890 static int dso__load_sym(struct dso *self, struct map *map, const char *name,
891                          int fd, symbol_filter_t filter, int kmodule)
892 {
893         struct kmap *kmap = self->kernel ? map__kmap(map) : NULL;
894         struct map *curr_map = map;
895         struct dso *curr_dso = self;
896         size_t dso_name_len = strlen(self->short_name);
897         Elf_Data *symstrs, *secstrs;
898         uint32_t nr_syms;
899         int err = -1;
900         uint32_t idx;
901         GElf_Ehdr ehdr;
902         GElf_Shdr shdr;
903         Elf_Data *syms;
904         GElf_Sym sym;
905         Elf_Scn *sec, *sec_strndx;
906         Elf *elf;
907         int nr = 0;
908
909         elf = elf_begin(fd, PERF_ELF_C_READ_MMAP, NULL);
910         if (elf == NULL) {
911                 pr_err("%s: cannot read %s ELF file.\n", __func__, name);
912                 goto out_close;
913         }
914
915         if (gelf_getehdr(elf, &ehdr) == NULL) {
916                 pr_err("%s: cannot get elf header.\n", __func__);
917                 goto out_elf_end;
918         }
919
920         sec = elf_section_by_name(elf, &ehdr, &shdr, ".symtab", NULL);
921         if (sec == NULL) {
922                 sec = elf_section_by_name(elf, &ehdr, &shdr, ".dynsym", NULL);
923                 if (sec == NULL)
924                         goto out_elf_end;
925         }
926
927         syms = elf_getdata(sec, NULL);
928         if (syms == NULL)
929                 goto out_elf_end;
930
931         sec = elf_getscn(elf, shdr.sh_link);
932         if (sec == NULL)
933                 goto out_elf_end;
934
935         symstrs = elf_getdata(sec, NULL);
936         if (symstrs == NULL)
937                 goto out_elf_end;
938
939         sec_strndx = elf_getscn(elf, ehdr.e_shstrndx);
940         if (sec_strndx == NULL)
941                 goto out_elf_end;
942
943         secstrs = elf_getdata(sec_strndx, NULL);
944         if (secstrs == NULL)
945                 goto out_elf_end;
946
947         nr_syms = shdr.sh_size / shdr.sh_entsize;
948
949         memset(&sym, 0, sizeof(sym));
950         if (!self->kernel) {
951                 self->adjust_symbols = (ehdr.e_type == ET_EXEC ||
952                                 elf_section_by_name(elf, &ehdr, &shdr,
953                                                      ".gnu.prelink_undo",
954                                                      NULL) != NULL);
955         } else self->adjust_symbols = 0;
956
957         elf_symtab__for_each_symbol(syms, nr_syms, idx, sym) {
958                 struct symbol *f;
959                 const char *elf_name = elf_sym__name(&sym, symstrs);
960                 char *demangled = NULL;
961                 int is_label = elf_sym__is_label(&sym);
962                 const char *section_name;
963
964                 if (kmap && kmap->ref_reloc_sym && kmap->ref_reloc_sym->name &&
965                     strcmp(elf_name, kmap->ref_reloc_sym->name) == 0)
966                         kmap->ref_reloc_sym->unrelocated_addr = sym.st_value;
967
968                 if (!is_label && !elf_sym__is_a(&sym, map->type))
969                         continue;
970
971                 sec = elf_getscn(elf, sym.st_shndx);
972                 if (!sec)
973                         goto out_elf_end;
974
975                 gelf_getshdr(sec, &shdr);
976
977                 if (is_label && !elf_sec__is_a(&shdr, secstrs, map->type))
978                         continue;
979
980                 section_name = elf_sec__name(&shdr, secstrs);
981
982                 if (self->kernel || kmodule) {
983                         char dso_name[PATH_MAX];
984
985                         if (strcmp(section_name,
986                                    curr_dso->short_name + dso_name_len) == 0)
987                                 goto new_symbol;
988
989                         if (strcmp(section_name, ".text") == 0) {
990                                 curr_map = map;
991                                 curr_dso = self;
992                                 goto new_symbol;
993                         }
994
995                         snprintf(dso_name, sizeof(dso_name),
996                                  "%s%s", self->short_name, section_name);
997
998                         curr_map = map_groups__find_by_name(kmap->kmaps, map->type, dso_name);
999                         if (curr_map == NULL) {
1000                                 u64 start = sym.st_value;
1001
1002                                 if (kmodule)
1003                                         start += map->start + shdr.sh_offset;
1004
1005                                 curr_dso = dso__new(dso_name);
1006                                 if (curr_dso == NULL)
1007                                         goto out_elf_end;
1008                                 curr_map = map__new2(start, curr_dso,
1009                                                      map->type);
1010                                 if (curr_map == NULL) {
1011                                         dso__delete(curr_dso);
1012                                         goto out_elf_end;
1013                                 }
1014                                 curr_map->map_ip = identity__map_ip;
1015                                 curr_map->unmap_ip = identity__map_ip;
1016                                 curr_dso->origin = DSO__ORIG_KERNEL;
1017                                 map_groups__insert(kmap->kmaps, curr_map);
1018                                 dsos__add(&dsos__kernel, curr_dso);
1019                                 dso__set_loaded(curr_dso, map->type);
1020                         } else
1021                                 curr_dso = curr_map->dso;
1022
1023                         goto new_symbol;
1024                 }
1025
1026                 if (curr_dso->adjust_symbols) {
1027                         pr_debug2("adjusting symbol: st_value: %Lx sh_addr: "
1028                                   "%Lx sh_offset: %Lx\n", (u64)sym.st_value,
1029                                   (u64)shdr.sh_addr, (u64)shdr.sh_offset);
1030                         sym.st_value -= shdr.sh_addr - shdr.sh_offset;
1031                 }
1032                 /*
1033                  * We need to figure out if the object was created from C++ sources
1034                  * DWARF DW_compile_unit has this, but we don't always have access
1035                  * to it...
1036                  */
1037                 demangled = bfd_demangle(NULL, elf_name, DMGL_PARAMS | DMGL_ANSI);
1038                 if (demangled != NULL)
1039                         elf_name = demangled;
1040 new_symbol:
1041                 f = symbol__new(sym.st_value, sym.st_size, elf_name);
1042                 free(demangled);
1043                 if (!f)
1044                         goto out_elf_end;
1045
1046                 if (filter && filter(curr_map, f))
1047                         symbol__delete(f);
1048                 else {
1049                         symbols__insert(&curr_dso->symbols[curr_map->type], f);
1050                         nr++;
1051                 }
1052         }
1053
1054         /*
1055          * For misannotated, zeroed, ASM function sizes.
1056          */
1057         if (nr > 0) {
1058                 symbols__fixup_end(&self->symbols[map->type]);
1059                 if (kmap) {
1060                         /*
1061                          * We need to fixup this here too because we create new
1062                          * maps here, for things like vsyscall sections.
1063                          */
1064                         __map_groups__fixup_end(kmap->kmaps, map->type);
1065                 }
1066         }
1067         err = nr;
1068 out_elf_end:
1069         elf_end(elf);
1070 out_close:
1071         return err;
1072 }
1073
1074 static bool dso__build_id_equal(const struct dso *self, u8 *build_id)
1075 {
1076         return memcmp(self->build_id, build_id, sizeof(self->build_id)) == 0;
1077 }
1078
1079 static bool __dsos__read_build_ids(struct list_head *head, bool with_hits)
1080 {
1081         bool have_build_id = false;
1082         struct dso *pos;
1083
1084         list_for_each_entry(pos, head, node) {
1085                 if (with_hits && !pos->hit)
1086                         continue;
1087                 if (filename__read_build_id(pos->long_name, pos->build_id,
1088                                             sizeof(pos->build_id)) > 0) {
1089                         have_build_id     = true;
1090                         pos->has_build_id = true;
1091                 }
1092         }
1093
1094         return have_build_id;
1095 }
1096
1097 bool dsos__read_build_ids(bool with_hits)
1098 {
1099         bool kbuildids = __dsos__read_build_ids(&dsos__kernel, with_hits),
1100              ubuildids = __dsos__read_build_ids(&dsos__user, with_hits);
1101         return kbuildids || ubuildids;
1102 }
1103
1104 /*
1105  * Align offset to 4 bytes as needed for note name and descriptor data.
1106  */
1107 #define NOTE_ALIGN(n) (((n) + 3) & -4U)
1108
1109 int filename__read_build_id(const char *filename, void *bf, size_t size)
1110 {
1111         int fd, err = -1;
1112         GElf_Ehdr ehdr;
1113         GElf_Shdr shdr;
1114         Elf_Data *data;
1115         Elf_Scn *sec;
1116         Elf_Kind ek;
1117         void *ptr;
1118         Elf *elf;
1119
1120         if (size < BUILD_ID_SIZE)
1121                 goto out;
1122
1123         fd = open(filename, O_RDONLY);
1124         if (fd < 0)
1125                 goto out;
1126
1127         elf = elf_begin(fd, PERF_ELF_C_READ_MMAP, NULL);
1128         if (elf == NULL) {
1129                 pr_debug2("%s: cannot read %s ELF file.\n", __func__, filename);
1130                 goto out_close;
1131         }
1132
1133         ek = elf_kind(elf);
1134         if (ek != ELF_K_ELF)
1135                 goto out_elf_end;
1136
1137         if (gelf_getehdr(elf, &ehdr) == NULL) {
1138                 pr_err("%s: cannot get elf header.\n", __func__);
1139                 goto out_elf_end;
1140         }
1141
1142         sec = elf_section_by_name(elf, &ehdr, &shdr,
1143                                   ".note.gnu.build-id", NULL);
1144         if (sec == NULL) {
1145                 sec = elf_section_by_name(elf, &ehdr, &shdr,
1146                                           ".notes", NULL);
1147                 if (sec == NULL)
1148                         goto out_elf_end;
1149         }
1150
1151         data = elf_getdata(sec, NULL);
1152         if (data == NULL)
1153                 goto out_elf_end;
1154
1155         ptr = data->d_buf;
1156         while (ptr < (data->d_buf + data->d_size)) {
1157                 GElf_Nhdr *nhdr = ptr;
1158                 int namesz = NOTE_ALIGN(nhdr->n_namesz),
1159                     descsz = NOTE_ALIGN(nhdr->n_descsz);
1160                 const char *name;
1161
1162                 ptr += sizeof(*nhdr);
1163                 name = ptr;
1164                 ptr += namesz;
1165                 if (nhdr->n_type == NT_GNU_BUILD_ID &&
1166                     nhdr->n_namesz == sizeof("GNU")) {
1167                         if (memcmp(name, "GNU", sizeof("GNU")) == 0) {
1168                                 memcpy(bf, ptr, BUILD_ID_SIZE);
1169                                 err = BUILD_ID_SIZE;
1170                                 break;
1171                         }
1172                 }
1173                 ptr += descsz;
1174         }
1175 out_elf_end:
1176         elf_end(elf);
1177 out_close:
1178         close(fd);
1179 out:
1180         return err;
1181 }
1182
1183 int sysfs__read_build_id(const char *filename, void *build_id, size_t size)
1184 {
1185         int fd, err = -1;
1186
1187         if (size < BUILD_ID_SIZE)
1188                 goto out;
1189
1190         fd = open(filename, O_RDONLY);
1191         if (fd < 0)
1192                 goto out;
1193
1194         while (1) {
1195                 char bf[BUFSIZ];
1196                 GElf_Nhdr nhdr;
1197                 int namesz, descsz;
1198
1199                 if (read(fd, &nhdr, sizeof(nhdr)) != sizeof(nhdr))
1200                         break;
1201
1202                 namesz = NOTE_ALIGN(nhdr.n_namesz);
1203                 descsz = NOTE_ALIGN(nhdr.n_descsz);
1204                 if (nhdr.n_type == NT_GNU_BUILD_ID &&
1205                     nhdr.n_namesz == sizeof("GNU")) {
1206                         if (read(fd, bf, namesz) != namesz)
1207                                 break;
1208                         if (memcmp(bf, "GNU", sizeof("GNU")) == 0) {
1209                                 if (read(fd, build_id,
1210                                     BUILD_ID_SIZE) == BUILD_ID_SIZE) {
1211                                         err = 0;
1212                                         break;
1213                                 }
1214                         } else if (read(fd, bf, descsz) != descsz)
1215                                 break;
1216                 } else {
1217                         int n = namesz + descsz;
1218                         if (read(fd, bf, n) != n)
1219                                 break;
1220                 }
1221         }
1222         close(fd);
1223 out:
1224         return err;
1225 }
1226
1227 char dso__symtab_origin(const struct dso *self)
1228 {
1229         static const char origin[] = {
1230                 [DSO__ORIG_KERNEL] =   'k',
1231                 [DSO__ORIG_JAVA_JIT] = 'j',
1232                 [DSO__ORIG_BUILD_ID_CACHE] = 'B',
1233                 [DSO__ORIG_FEDORA] =   'f',
1234                 [DSO__ORIG_UBUNTU] =   'u',
1235                 [DSO__ORIG_BUILDID] =  'b',
1236                 [DSO__ORIG_DSO] =      'd',
1237                 [DSO__ORIG_KMODULE] =  'K',
1238         };
1239
1240         if (self == NULL || self->origin == DSO__ORIG_NOT_FOUND)
1241                 return '!';
1242         return origin[self->origin];
1243 }
1244
1245 int dso__load(struct dso *self, struct map *map, symbol_filter_t filter)
1246 {
1247         int size = PATH_MAX;
1248         char *name;
1249         u8 build_id[BUILD_ID_SIZE];
1250         char build_id_hex[BUILD_ID_SIZE * 2 + 1];
1251         int ret = -1;
1252         int fd;
1253
1254         dso__set_loaded(self, map->type);
1255
1256         if (self->kernel)
1257                 return dso__load_kernel_sym(self, map, filter);
1258
1259         name = malloc(size);
1260         if (!name)
1261                 return -1;
1262
1263         self->adjust_symbols = 0;
1264
1265         if (strncmp(self->name, "/tmp/perf-", 10) == 0) {
1266                 ret = dso__load_perf_map(self, map, filter);
1267                 self->origin = ret > 0 ? DSO__ORIG_JAVA_JIT :
1268                                          DSO__ORIG_NOT_FOUND;
1269                 return ret;
1270         }
1271
1272         self->origin = DSO__ORIG_BUILD_ID_CACHE;
1273
1274         if (self->has_build_id) {
1275                 build_id__sprintf(self->build_id, sizeof(self->build_id),
1276                                   build_id_hex);
1277                 snprintf(name, size, "%s/%s/.build-id/%.2s/%s",
1278                          getenv("HOME"), DEBUG_CACHE_DIR,
1279                          build_id_hex, build_id_hex + 2);
1280                 goto open_file;
1281         }
1282 more:
1283         do {
1284                 self->origin++;
1285                 switch (self->origin) {
1286                 case DSO__ORIG_FEDORA:
1287                         snprintf(name, size, "/usr/lib/debug%s.debug",
1288                                  self->long_name);
1289                         break;
1290                 case DSO__ORIG_UBUNTU:
1291                         snprintf(name, size, "/usr/lib/debug%s",
1292                                  self->long_name);
1293                         break;
1294                 case DSO__ORIG_BUILDID:
1295                         if (filename__read_build_id(self->long_name, build_id,
1296                                                     sizeof(build_id))) {
1297                                 build_id__sprintf(build_id, sizeof(build_id),
1298                                                   build_id_hex);
1299                                 snprintf(name, size,
1300                                          "/usr/lib/debug/.build-id/%.2s/%s.debug",
1301                                         build_id_hex, build_id_hex + 2);
1302                                 if (self->has_build_id)
1303                                         goto compare_build_id;
1304                                 break;
1305                         }
1306                         self->origin++;
1307                         /* Fall thru */
1308                 case DSO__ORIG_DSO:
1309                         snprintf(name, size, "%s", self->long_name);
1310                         break;
1311
1312                 default:
1313                         goto out;
1314                 }
1315
1316                 if (self->has_build_id) {
1317                         if (filename__read_build_id(name, build_id,
1318                                                     sizeof(build_id)) < 0)
1319                                 goto more;
1320 compare_build_id:
1321                         if (!dso__build_id_equal(self, build_id))
1322                                 goto more;
1323                 }
1324 open_file:
1325                 fd = open(name, O_RDONLY);
1326         } while (fd < 0);
1327
1328         ret = dso__load_sym(self, map, name, fd, filter, 0);
1329         close(fd);
1330
1331         /*
1332          * Some people seem to have debuginfo files _WITHOUT_ debug info!?!?
1333          */
1334         if (!ret)
1335                 goto more;
1336
1337         if (ret > 0) {
1338                 int nr_plt = dso__synthesize_plt_symbols(self, map, filter);
1339                 if (nr_plt > 0)
1340                         ret += nr_plt;
1341         }
1342 out:
1343         free(name);
1344         if (ret < 0 && strstr(self->name, " (deleted)") != NULL)
1345                 return 0;
1346         return ret;
1347 }
1348
1349 struct map *map_groups__find_by_name(struct map_groups *self,
1350                                      enum map_type type, const char *name)
1351 {
1352         struct rb_node *nd;
1353
1354         for (nd = rb_first(&self->maps[type]); nd; nd = rb_next(nd)) {
1355                 struct map *map = rb_entry(nd, struct map, rb_node);
1356
1357                 if (map->dso && strcmp(map->dso->short_name, name) == 0)
1358                         return map;
1359         }
1360
1361         return NULL;
1362 }
1363
1364 static int dso__kernel_module_get_build_id(struct dso *self)
1365 {
1366         char filename[PATH_MAX];
1367         /*
1368          * kernel module short names are of the form "[module]" and
1369          * we need just "module" here.
1370          */
1371         const char *name = self->short_name + 1;
1372
1373         snprintf(filename, sizeof(filename),
1374                  "/sys/module/%.*s/notes/.note.gnu.build-id",
1375                  (int)strlen(name - 1), name);
1376
1377         if (sysfs__read_build_id(filename, self->build_id,
1378                                  sizeof(self->build_id)) == 0)
1379                 self->has_build_id = true;
1380
1381         return 0;
1382 }
1383
1384 static int map_groups__set_modules_path_dir(struct map_groups *self, char *dirname)
1385 {
1386         struct dirent *dent;
1387         DIR *dir = opendir(dirname);
1388
1389         if (!dir) {
1390                 pr_debug("%s: cannot open %s dir\n", __func__, dirname);
1391                 return -1;
1392         }
1393
1394         while ((dent = readdir(dir)) != NULL) {
1395                 char path[PATH_MAX];
1396
1397                 if (dent->d_type == DT_DIR) {
1398                         if (!strcmp(dent->d_name, ".") ||
1399                             !strcmp(dent->d_name, ".."))
1400                                 continue;
1401
1402                         snprintf(path, sizeof(path), "%s/%s",
1403                                  dirname, dent->d_name);
1404                         if (map_groups__set_modules_path_dir(self, path) < 0)
1405                                 goto failure;
1406                 } else {
1407                         char *dot = strrchr(dent->d_name, '.'),
1408                              dso_name[PATH_MAX];
1409                         struct map *map;
1410                         char *long_name;
1411
1412                         if (dot == NULL || strcmp(dot, ".ko"))
1413                                 continue;
1414                         snprintf(dso_name, sizeof(dso_name), "[%.*s]",
1415                                  (int)(dot - dent->d_name), dent->d_name);
1416
1417                         strxfrchar(dso_name, '-', '_');
1418                         map = map_groups__find_by_name(self, MAP__FUNCTION, dso_name);
1419                         if (map == NULL)
1420                                 continue;
1421
1422                         snprintf(path, sizeof(path), "%s/%s",
1423                                  dirname, dent->d_name);
1424
1425                         long_name = strdup(path);
1426                         if (long_name == NULL)
1427                                 goto failure;
1428                         dso__set_long_name(map->dso, long_name);
1429                         dso__kernel_module_get_build_id(map->dso);
1430                 }
1431         }
1432
1433         return 0;
1434 failure:
1435         closedir(dir);
1436         return -1;
1437 }
1438
1439 static int map_groups__set_modules_path(struct map_groups *self)
1440 {
1441         struct utsname uts;
1442         char modules_path[PATH_MAX];
1443
1444         if (uname(&uts) < 0)
1445                 return -1;
1446
1447         snprintf(modules_path, sizeof(modules_path), "/lib/modules/%s/kernel",
1448                  uts.release);
1449
1450         return map_groups__set_modules_path_dir(self, modules_path);
1451 }
1452
1453 /*
1454  * Constructor variant for modules (where we know from /proc/modules where
1455  * they are loaded) and for vmlinux, where only after we load all the
1456  * symbols we'll know where it starts and ends.
1457  */
1458 static struct map *map__new2(u64 start, struct dso *dso, enum map_type type)
1459 {
1460         struct map *self = zalloc(sizeof(*self) +
1461                                   (dso->kernel ? sizeof(struct kmap) : 0));
1462         if (self != NULL) {
1463                 /*
1464                  * ->end will be filled after we load all the symbols
1465                  */
1466                 map__init(self, type, start, 0, 0, dso);
1467         }
1468
1469         return self;
1470 }
1471
1472 struct map *map_groups__new_module(struct map_groups *self, u64 start,
1473                                    const char *filename)
1474 {
1475         struct map *map;
1476         struct dso *dso = __dsos__findnew(&dsos__kernel, filename);
1477
1478         if (dso == NULL)
1479                 return NULL;
1480
1481         map = map__new2(start, dso, MAP__FUNCTION);
1482         if (map == NULL)
1483                 return NULL;
1484
1485         dso->origin = DSO__ORIG_KMODULE;
1486         map_groups__insert(self, map);
1487         return map;
1488 }
1489
1490 static int map_groups__create_modules(struct map_groups *self)
1491 {
1492         char *line = NULL;
1493         size_t n;
1494         FILE *file = fopen("/proc/modules", "r");
1495         struct map *map;
1496
1497         if (file == NULL)
1498                 return -1;
1499
1500         while (!feof(file)) {
1501                 char name[PATH_MAX];
1502                 u64 start;
1503                 char *sep;
1504                 int line_len;
1505
1506                 line_len = getline(&line, &n, file);
1507                 if (line_len < 0)
1508                         break;
1509
1510                 if (!line)
1511                         goto out_failure;
1512
1513                 line[--line_len] = '\0'; /* \n */
1514
1515                 sep = strrchr(line, 'x');
1516                 if (sep == NULL)
1517                         continue;
1518
1519                 hex2u64(sep + 1, &start);
1520
1521                 sep = strchr(line, ' ');
1522                 if (sep == NULL)
1523                         continue;
1524
1525                 *sep = '\0';
1526
1527                 snprintf(name, sizeof(name), "[%s]", line);
1528                 map = map_groups__new_module(self, start, name);
1529                 if (map == NULL)
1530                         goto out_delete_line;
1531                 dso__kernel_module_get_build_id(map->dso);
1532         }
1533
1534         free(line);
1535         fclose(file);
1536
1537         return map_groups__set_modules_path(self);
1538
1539 out_delete_line:
1540         free(line);
1541 out_failure:
1542         return -1;
1543 }
1544
1545 static int dso__load_vmlinux(struct dso *self, struct map *map,
1546                              const char *vmlinux, symbol_filter_t filter)
1547 {
1548         int err = -1, fd;
1549
1550         if (self->has_build_id) {
1551                 u8 build_id[BUILD_ID_SIZE];
1552
1553                 if (filename__read_build_id(vmlinux, build_id,
1554                                             sizeof(build_id)) < 0) {
1555                         pr_debug("No build_id in %s, ignoring it\n", vmlinux);
1556                         return -1;
1557                 }
1558                 if (!dso__build_id_equal(self, build_id)) {
1559                         char expected_build_id[BUILD_ID_SIZE * 2 + 1],
1560                              vmlinux_build_id[BUILD_ID_SIZE * 2 + 1];
1561
1562                         build_id__sprintf(self->build_id,
1563                                           sizeof(self->build_id),
1564                                           expected_build_id);
1565                         build_id__sprintf(build_id, sizeof(build_id),
1566                                           vmlinux_build_id);
1567                         pr_debug("build_id in %s is %s while expected is %s, "
1568                                  "ignoring it\n", vmlinux, vmlinux_build_id,
1569                                  expected_build_id);
1570                         return -1;
1571                 }
1572         }
1573
1574         fd = open(vmlinux, O_RDONLY);
1575         if (fd < 0)
1576                 return -1;
1577
1578         dso__set_loaded(self, map->type);
1579         err = dso__load_sym(self, map, vmlinux, fd, filter, 0);
1580         close(fd);
1581
1582         return err;
1583 }
1584
1585 int dso__load_vmlinux_path(struct dso *self, struct map *map,
1586                            symbol_filter_t filter)
1587 {
1588         int i, err = 0;
1589
1590         pr_debug("Looking at the vmlinux_path (%d entries long)\n",
1591                  vmlinux_path__nr_entries);
1592
1593         for (i = 0; i < vmlinux_path__nr_entries; ++i) {
1594                 err = dso__load_vmlinux(self, map, vmlinux_path[i], filter);
1595                 if (err > 0) {
1596                         pr_debug("Using %s for symbols\n", vmlinux_path[i]);
1597                         dso__set_long_name(self, strdup(vmlinux_path[i]));
1598                         break;
1599                 }
1600         }
1601
1602         return err;
1603 }
1604
1605 static int dso__load_kernel_sym(struct dso *self, struct map *map,
1606                                 symbol_filter_t filter)
1607 {
1608         int err;
1609         const char *kallsyms_filename = NULL;
1610         char *kallsyms_allocated_filename = NULL;
1611         /*
1612          * Step 1: if the user specified a vmlinux filename, use it and only
1613          * it, reporting errors to the user if it cannot be used.
1614          *
1615          * For instance, try to analyse an ARM perf.data file _without_ a
1616          * build-id, or if the user specifies the wrong path to the right
1617          * vmlinux file, obviously we can't fallback to another vmlinux (a
1618          * x86_86 one, on the machine where analysis is being performed, say),
1619          * or worse, /proc/kallsyms.
1620          *
1621          * If the specified file _has_ a build-id and there is a build-id
1622          * section in the perf.data file, we will still do the expected
1623          * validation in dso__load_vmlinux and will bail out if they don't
1624          * match.
1625          */
1626         if (symbol_conf.vmlinux_name != NULL) {
1627                 err = dso__load_vmlinux(self, map,
1628                                         symbol_conf.vmlinux_name, filter);
1629                 goto out_try_fixup;
1630         }
1631
1632         if (vmlinux_path != NULL) {
1633                 err = dso__load_vmlinux_path(self, map, filter);
1634                 if (err > 0)
1635                         goto out_fixup;
1636         }
1637
1638         /*
1639          * Say the kernel DSO was created when processing the build-id header table,
1640          * we have a build-id, so check if it is the same as the running kernel,
1641          * using it if it is.
1642          */
1643         if (self->has_build_id) {
1644                 u8 kallsyms_build_id[BUILD_ID_SIZE];
1645                 char sbuild_id[BUILD_ID_SIZE * 2 + 1];
1646
1647                 if (sysfs__read_build_id("/sys/kernel/notes", kallsyms_build_id,
1648                                          sizeof(kallsyms_build_id)) == 0) {
1649                         if (dso__build_id_equal(self, kallsyms_build_id)) {
1650                                 kallsyms_filename = "/proc/kallsyms";
1651                                 goto do_kallsyms;
1652                         }
1653                 }
1654                 /*
1655                  * Now look if we have it on the build-id cache in
1656                  * $HOME/.debug/[kernel.kallsyms].
1657                  */
1658                 build_id__sprintf(self->build_id, sizeof(self->build_id),
1659                                   sbuild_id);
1660
1661                 if (asprintf(&kallsyms_allocated_filename,
1662                              "%s/.debug/[kernel.kallsyms]/%s",
1663                              getenv("HOME"), sbuild_id) == -1)
1664                         return -1;
1665
1666                 kallsyms_filename = kallsyms_allocated_filename;
1667
1668                 if (access(kallsyms_filename, F_OK)) {
1669                         free(kallsyms_allocated_filename);
1670                         return -1;
1671                 }
1672         } else {
1673                 /*
1674                  * Last resort, if we don't have a build-id and couldn't find
1675                  * any vmlinux file, try the running kernel kallsyms table.
1676                  */
1677                 kallsyms_filename = "/proc/kallsyms";
1678         }
1679
1680 do_kallsyms:
1681         err = dso__load_kallsyms(self, kallsyms_filename, map, filter);
1682         free(kallsyms_allocated_filename);
1683
1684 out_try_fixup:
1685         if (err > 0) {
1686 out_fixup:
1687                 if (kallsyms_filename != NULL)
1688                         dso__set_long_name(self, strdup("[kernel.kallsyms]"));
1689                 map__fixup_start(map);
1690                 map__fixup_end(map);
1691         }
1692
1693         return err;
1694 }
1695
1696 LIST_HEAD(dsos__user);
1697 LIST_HEAD(dsos__kernel);
1698
1699 static void dsos__add(struct list_head *head, struct dso *dso)
1700 {
1701         list_add_tail(&dso->node, head);
1702 }
1703
1704 static struct dso *dsos__find(struct list_head *head, const char *name)
1705 {
1706         struct dso *pos;
1707
1708         list_for_each_entry(pos, head, node)
1709                 if (strcmp(pos->long_name, name) == 0)
1710                         return pos;
1711         return NULL;
1712 }
1713
1714 struct dso *__dsos__findnew(struct list_head *head, const char *name)
1715 {
1716         struct dso *dso = dsos__find(head, name);
1717
1718         if (!dso) {
1719                 dso = dso__new(name);
1720                 if (dso != NULL) {
1721                         dsos__add(head, dso);
1722                         dso__set_basename(dso);
1723                 }
1724         }
1725
1726         return dso;
1727 }
1728
1729 static void __dsos__fprintf(struct list_head *head, FILE *fp)
1730 {
1731         struct dso *pos;
1732
1733         list_for_each_entry(pos, head, node) {
1734                 int i;
1735                 for (i = 0; i < MAP__NR_TYPES; ++i)
1736                         dso__fprintf(pos, i, fp);
1737         }
1738 }
1739
1740 void dsos__fprintf(FILE *fp)
1741 {
1742         __dsos__fprintf(&dsos__kernel, fp);
1743         __dsos__fprintf(&dsos__user, fp);
1744 }
1745
1746 static size_t __dsos__fprintf_buildid(struct list_head *head, FILE *fp,
1747                                       bool with_hits)
1748 {
1749         struct dso *pos;
1750         size_t ret = 0;
1751
1752         list_for_each_entry(pos, head, node) {
1753                 if (with_hits && !pos->hit)
1754                         continue;
1755                 ret += dso__fprintf_buildid(pos, fp);
1756                 ret += fprintf(fp, " %s\n", pos->long_name);
1757         }
1758         return ret;
1759 }
1760
1761 size_t dsos__fprintf_buildid(FILE *fp, bool with_hits)
1762 {
1763         return (__dsos__fprintf_buildid(&dsos__kernel, fp, with_hits) +
1764                 __dsos__fprintf_buildid(&dsos__user, fp, with_hits));
1765 }
1766
1767 struct dso *dso__new_kernel(const char *name)
1768 {
1769         struct dso *self = dso__new(name ?: "[kernel.kallsyms]");
1770
1771         if (self != NULL) {
1772                 self->short_name = "[kernel]";
1773                 self->kernel     = 1;
1774         }
1775
1776         return self;
1777 }
1778
1779 void dso__read_running_kernel_build_id(struct dso *self)
1780 {
1781         if (sysfs__read_build_id("/sys/kernel/notes", self->build_id,
1782                                  sizeof(self->build_id)) == 0)
1783                 self->has_build_id = true;
1784 }
1785
1786 static struct dso *dsos__create_kernel(const char *vmlinux)
1787 {
1788         struct dso *kernel = dso__new_kernel(vmlinux);
1789
1790         if (kernel != NULL) {
1791                 dso__read_running_kernel_build_id(kernel);
1792                 dsos__add(&dsos__kernel, kernel);
1793         }
1794
1795         return kernel;
1796 }
1797
1798 int __map_groups__create_kernel_maps(struct map_groups *self,
1799                                      struct map *vmlinux_maps[MAP__NR_TYPES],
1800                                      struct dso *kernel)
1801 {
1802         enum map_type type;
1803
1804         for (type = 0; type < MAP__NR_TYPES; ++type) {
1805                 struct kmap *kmap;
1806
1807                 vmlinux_maps[type] = map__new2(0, kernel, type);
1808                 if (vmlinux_maps[type] == NULL)
1809                         return -1;
1810
1811                 vmlinux_maps[type]->map_ip =
1812                         vmlinux_maps[type]->unmap_ip = identity__map_ip;
1813
1814                 kmap = map__kmap(vmlinux_maps[type]);
1815                 kmap->kmaps = self;
1816                 map_groups__insert(self, vmlinux_maps[type]);
1817         }
1818
1819         return 0;
1820 }
1821
1822 static void vmlinux_path__exit(void)
1823 {
1824         while (--vmlinux_path__nr_entries >= 0) {
1825                 free(vmlinux_path[vmlinux_path__nr_entries]);
1826                 vmlinux_path[vmlinux_path__nr_entries] = NULL;
1827         }
1828
1829         free(vmlinux_path);
1830         vmlinux_path = NULL;
1831 }
1832
1833 static int vmlinux_path__init(void)
1834 {
1835         struct utsname uts;
1836         char bf[PATH_MAX];
1837
1838         if (uname(&uts) < 0)
1839                 return -1;
1840
1841         vmlinux_path = malloc(sizeof(char *) * 5);
1842         if (vmlinux_path == NULL)
1843                 return -1;
1844
1845         vmlinux_path[vmlinux_path__nr_entries] = strdup("vmlinux");
1846         if (vmlinux_path[vmlinux_path__nr_entries] == NULL)
1847                 goto out_fail;
1848         ++vmlinux_path__nr_entries;
1849         vmlinux_path[vmlinux_path__nr_entries] = strdup("/boot/vmlinux");
1850         if (vmlinux_path[vmlinux_path__nr_entries] == NULL)
1851                 goto out_fail;
1852         ++vmlinux_path__nr_entries;
1853         snprintf(bf, sizeof(bf), "/boot/vmlinux-%s", uts.release);
1854         vmlinux_path[vmlinux_path__nr_entries] = strdup(bf);
1855         if (vmlinux_path[vmlinux_path__nr_entries] == NULL)
1856                 goto out_fail;
1857         ++vmlinux_path__nr_entries;
1858         snprintf(bf, sizeof(bf), "/lib/modules/%s/build/vmlinux", uts.release);
1859         vmlinux_path[vmlinux_path__nr_entries] = strdup(bf);
1860         if (vmlinux_path[vmlinux_path__nr_entries] == NULL)
1861                 goto out_fail;
1862         ++vmlinux_path__nr_entries;
1863         snprintf(bf, sizeof(bf), "/usr/lib/debug/lib/modules/%s/vmlinux",
1864                  uts.release);
1865         vmlinux_path[vmlinux_path__nr_entries] = strdup(bf);
1866         if (vmlinux_path[vmlinux_path__nr_entries] == NULL)
1867                 goto out_fail;
1868         ++vmlinux_path__nr_entries;
1869
1870         return 0;
1871
1872 out_fail:
1873         vmlinux_path__exit();
1874         return -1;
1875 }
1876
1877 static int setup_list(struct strlist **list, const char *list_str,
1878                       const char *list_name)
1879 {
1880         if (list_str == NULL)
1881                 return 0;
1882
1883         *list = strlist__new(true, list_str);
1884         if (!*list) {
1885                 pr_err("problems parsing %s list\n", list_name);
1886                 return -1;
1887         }
1888         return 0;
1889 }
1890
1891 int symbol__init(void)
1892 {
1893         elf_version(EV_CURRENT);
1894         if (symbol_conf.sort_by_name)
1895                 symbol_conf.priv_size += (sizeof(struct symbol_name_rb_node) -
1896                                           sizeof(struct symbol));
1897
1898         if (symbol_conf.try_vmlinux_path && vmlinux_path__init() < 0)
1899                 return -1;
1900
1901         if (symbol_conf.field_sep && *symbol_conf.field_sep == '.') {
1902                 pr_err("'.' is the only non valid --field-separator argument\n");
1903                 return -1;
1904         }
1905
1906         if (setup_list(&symbol_conf.dso_list,
1907                        symbol_conf.dso_list_str, "dso") < 0)
1908                 return -1;
1909
1910         if (setup_list(&symbol_conf.comm_list,
1911                        symbol_conf.comm_list_str, "comm") < 0)
1912                 goto out_free_dso_list;
1913
1914         if (setup_list(&symbol_conf.sym_list,
1915                        symbol_conf.sym_list_str, "symbol") < 0)
1916                 goto out_free_comm_list;
1917
1918         return 0;
1919
1920 out_free_dso_list:
1921         strlist__delete(symbol_conf.dso_list);
1922 out_free_comm_list:
1923         strlist__delete(symbol_conf.comm_list);
1924         return -1;
1925 }
1926
1927 int map_groups__create_kernel_maps(struct map_groups *self,
1928                                    struct map *vmlinux_maps[MAP__NR_TYPES])
1929 {
1930         struct dso *kernel = dsos__create_kernel(symbol_conf.vmlinux_name);
1931
1932         if (kernel == NULL)
1933                 return -1;
1934
1935         if (__map_groups__create_kernel_maps(self, vmlinux_maps, kernel) < 0)
1936                 return -1;
1937
1938         if (symbol_conf.use_modules && map_groups__create_modules(self) < 0)
1939                 return -1;
1940         /*
1941          * Now that we have all the maps created, just set the ->end of them:
1942          */
1943         map_groups__fixup_end(self);
1944         return 0;
1945 }