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Linux/tools/perf/util/symbol.c

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  1 #include "util.h"
  2 #include "../perf.h"
  3 #include "string.h"
  4 #include "symbol.h"
  5 
  6 #include "debug.h"
  7 
  8 #include <libelf.h>
  9 #include <gelf.h>
 10 #include <elf.h>
 11 
 12 const char *sym_hist_filter;
 13 
 14 enum dso_origin {
 15         DSO__ORIG_KERNEL = 0,
 16         DSO__ORIG_JAVA_JIT,
 17         DSO__ORIG_FEDORA,
 18         DSO__ORIG_UBUNTU,
 19         DSO__ORIG_BUILDID,
 20         DSO__ORIG_DSO,
 21         DSO__ORIG_NOT_FOUND,
 22 };
 23 
 24 static struct symbol *symbol__new(u64 start, u64 len,
 25                                   const char *name, unsigned int priv_size,
 26                                   u64 obj_start, int v)
 27 {
 28         size_t namelen = strlen(name) + 1;
 29         struct symbol *self = calloc(1, priv_size + sizeof(*self) + namelen);
 30 
 31         if (!self)
 32                 return NULL;
 33 
 34         if (v >= 2)
 35                 printf("new symbol: %016Lx [%08lx]: %s, hist: %p, obj_start: %p\n",
 36                         (u64)start, (unsigned long)len, name, self->hist, (void *)(unsigned long)obj_start);
 37 
 38         self->obj_start= obj_start;
 39         self->hist = NULL;
 40         self->hist_sum = 0;
 41 
 42         if (sym_hist_filter && !strcmp(name, sym_hist_filter))
 43                 self->hist = calloc(sizeof(u64), len);
 44 
 45         if (priv_size) {
 46                 memset(self, 0, priv_size);
 47                 self = ((void *)self) + priv_size;
 48         }
 49         self->start = start;
 50         self->end   = len ? start + len - 1 : start;
 51         memcpy(self->name, name, namelen);
 52 
 53         return self;
 54 }
 55 
 56 static void symbol__delete(struct symbol *self, unsigned int priv_size)
 57 {
 58         free(((void *)self) - priv_size);
 59 }
 60 
 61 static size_t symbol__fprintf(struct symbol *self, FILE *fp)
 62 {
 63         if (!self->module)
 64                 return fprintf(fp, " %llx-%llx %s\n",
 65                        self->start, self->end, self->name);
 66         else
 67                 return fprintf(fp, " %llx-%llx %s \t[%s]\n",
 68                        self->start, self->end, self->name, self->module->name);
 69 }
 70 
 71 struct dso *dso__new(const char *name, unsigned int sym_priv_size)
 72 {
 73         struct dso *self = malloc(sizeof(*self) + strlen(name) + 1);
 74 
 75         if (self != NULL) {
 76                 strcpy(self->name, name);
 77                 self->syms = RB_ROOT;
 78                 self->sym_priv_size = sym_priv_size;
 79                 self->find_symbol = dso__find_symbol;
 80                 self->slen_calculated = 0;
 81                 self->origin = DSO__ORIG_NOT_FOUND;
 82         }
 83 
 84         return self;
 85 }
 86 
 87 static void dso__delete_symbols(struct dso *self)
 88 {
 89         struct symbol *pos;
 90         struct rb_node *next = rb_first(&self->syms);
 91 
 92         while (next) {
 93                 pos = rb_entry(next, struct symbol, rb_node);
 94                 next = rb_next(&pos->rb_node);
 95                 rb_erase(&pos->rb_node, &self->syms);
 96                 symbol__delete(pos, self->sym_priv_size);
 97         }
 98 }
 99 
100 void dso__delete(struct dso *self)
101 {
102         dso__delete_symbols(self);
103         free(self);
104 }
105 
106 static void dso__insert_symbol(struct dso *self, struct symbol *sym)
107 {
108         struct rb_node **p = &self->syms.rb_node;
109         struct rb_node *parent = NULL;
110         const u64 ip = sym->start;
111         struct symbol *s;
112 
113         while (*p != NULL) {
114                 parent = *p;
115                 s = rb_entry(parent, struct symbol, rb_node);
116                 if (ip < s->start)
117                         p = &(*p)->rb_left;
118                 else
119                         p = &(*p)->rb_right;
120         }
121         rb_link_node(&sym->rb_node, parent, p);
122         rb_insert_color(&sym->rb_node, &self->syms);
123 }
124 
125 struct symbol *dso__find_symbol(struct dso *self, u64 ip)
126 {
127         struct rb_node *n;
128 
129         if (self == NULL)
130                 return NULL;
131 
132         n = self->syms.rb_node;
133 
134         while (n) {
135                 struct symbol *s = rb_entry(n, struct symbol, rb_node);
136 
137                 if (ip < s->start)
138                         n = n->rb_left;
139                 else if (ip > s->end)
140                         n = n->rb_right;
141                 else
142                         return s;
143         }
144 
145         return NULL;
146 }
147 
148 size_t dso__fprintf(struct dso *self, FILE *fp)
149 {
150         size_t ret = fprintf(fp, "dso: %s\n", self->name);
151 
152         struct rb_node *nd;
153         for (nd = rb_first(&self->syms); nd; nd = rb_next(nd)) {
154                 struct symbol *pos = rb_entry(nd, struct symbol, rb_node);
155                 ret += symbol__fprintf(pos, fp);
156         }
157 
158         return ret;
159 }
160 
161 static int dso__load_kallsyms(struct dso *self, symbol_filter_t filter, int v)
162 {
163         struct rb_node *nd, *prevnd;
164         char *line = NULL;
165         size_t n;
166         FILE *file = fopen("/proc/kallsyms", "r");
167         int count = 0;
168 
169         if (file == NULL)
170                 goto out_failure;
171 
172         while (!feof(file)) {
173                 u64 start;
174                 struct symbol *sym;
175                 int line_len, len;
176                 char symbol_type;
177 
178                 line_len = getline(&line, &n, file);
179                 if (line_len < 0)
180                         break;
181 
182                 if (!line)
183                         goto out_failure;
184 
185                 line[--line_len] = '\0'; /* \n */
186 
187                 len = hex2u64(line, &start);
188 
189                 len++;
190                 if (len + 2 >= line_len)
191                         continue;
192 
193                 symbol_type = toupper(line[len]);
194                 /*
195                  * We're interested only in code ('T'ext)
196                  */
197                 if (symbol_type != 'T' && symbol_type != 'W')
198                         continue;
199                 /*
200                  * Well fix up the end later, when we have all sorted.
201                  */
202                 sym = symbol__new(start, 0xdead, line + len + 2,
203                                   self->sym_priv_size, 0, v);
204 
205                 if (sym == NULL)
206                         goto out_delete_line;
207 
208                 if (filter && filter(self, sym))
209                         symbol__delete(sym, self->sym_priv_size);
210                 else {
211                         dso__insert_symbol(self, sym);
212                         count++;
213                 }
214         }
215 
216         /*
217          * Now that we have all sorted out, just set the ->end of all
218          * symbols
219          */
220         prevnd = rb_first(&self->syms);
221 
222         if (prevnd == NULL)
223                 goto out_delete_line;
224 
225         for (nd = rb_next(prevnd); nd; nd = rb_next(nd)) {
226                 struct symbol *prev = rb_entry(prevnd, struct symbol, rb_node),
227                               *curr = rb_entry(nd, struct symbol, rb_node);
228 
229                 prev->end = curr->start - 1;
230                 prevnd = nd;
231         }
232 
233         free(line);
234         fclose(file);
235 
236         return count;
237 
238 out_delete_line:
239         free(line);
240 out_failure:
241         return -1;
242 }
243 
244 static int dso__load_perf_map(struct dso *self, symbol_filter_t filter, int v)
245 {
246         char *line = NULL;
247         size_t n;
248         FILE *file;
249         int nr_syms = 0;
250 
251         file = fopen(self->name, "r");
252         if (file == NULL)
253                 goto out_failure;
254 
255         while (!feof(file)) {
256                 u64 start, size;
257                 struct symbol *sym;
258                 int line_len, len;
259 
260                 line_len = getline(&line, &n, file);
261                 if (line_len < 0)
262                         break;
263 
264                 if (!line)
265                         goto out_failure;
266 
267                 line[--line_len] = '\0'; /* \n */
268 
269                 len = hex2u64(line, &start);
270 
271                 len++;
272                 if (len + 2 >= line_len)
273                         continue;
274 
275                 len += hex2u64(line + len, &size);
276 
277                 len++;
278                 if (len + 2 >= line_len)
279                         continue;
280 
281                 sym = symbol__new(start, size, line + len,
282                                   self->sym_priv_size, start, v);
283 
284                 if (sym == NULL)
285                         goto out_delete_line;
286 
287                 if (filter && filter(self, sym))
288                         symbol__delete(sym, self->sym_priv_size);
289                 else {
290                         dso__insert_symbol(self, sym);
291                         nr_syms++;
292                 }
293         }
294 
295         free(line);
296         fclose(file);
297 
298         return nr_syms;
299 
300 out_delete_line:
301         free(line);
302 out_failure:
303         return -1;
304 }
305 
306 /**
307  * elf_symtab__for_each_symbol - iterate thru all the symbols
308  *
309  * @self: struct elf_symtab instance to iterate
310  * @idx: uint32_t idx
311  * @sym: GElf_Sym iterator
312  */
313 #define elf_symtab__for_each_symbol(syms, nr_syms, idx, sym) \
314         for (idx = 0, gelf_getsym(syms, idx, &sym);\
315              idx < nr_syms; \
316              idx++, gelf_getsym(syms, idx, &sym))
317 
318 static inline uint8_t elf_sym__type(const GElf_Sym *sym)
319 {
320         return GELF_ST_TYPE(sym->st_info);
321 }
322 
323 static inline int elf_sym__is_function(const GElf_Sym *sym)
324 {
325         return elf_sym__type(sym) == STT_FUNC &&
326                sym->st_name != 0 &&
327                sym->st_shndx != SHN_UNDEF;
328 }
329 
330 static inline int elf_sym__is_label(const GElf_Sym *sym)
331 {
332         return elf_sym__type(sym) == STT_NOTYPE &&
333                 sym->st_name != 0 &&
334                 sym->st_shndx != SHN_UNDEF &&
335                 sym->st_shndx != SHN_ABS;
336 }
337 
338 static inline const char *elf_sec__name(const GElf_Shdr *shdr,
339                                         const Elf_Data *secstrs)
340 {
341         return secstrs->d_buf + shdr->sh_name;
342 }
343 
344 static inline int elf_sec__is_text(const GElf_Shdr *shdr,
345                                         const Elf_Data *secstrs)
346 {
347         return strstr(elf_sec__name(shdr, secstrs), "text") != NULL;
348 }
349 
350 static inline const char *elf_sym__name(const GElf_Sym *sym,
351                                         const Elf_Data *symstrs)
352 {
353         return symstrs->d_buf + sym->st_name;
354 }
355 
356 static Elf_Scn *elf_section_by_name(Elf *elf, GElf_Ehdr *ep,
357                                     GElf_Shdr *shp, const char *name,
358                                     size_t *idx)
359 {
360         Elf_Scn *sec = NULL;
361         size_t cnt = 1;
362 
363         while ((sec = elf_nextscn(elf, sec)) != NULL) {
364                 char *str;
365 
366                 gelf_getshdr(sec, shp);
367                 str = elf_strptr(elf, ep->e_shstrndx, shp->sh_name);
368                 if (!strcmp(name, str)) {
369                         if (idx)
370                                 *idx = cnt;
371                         break;
372                 }
373                 ++cnt;
374         }
375 
376         return sec;
377 }
378 
379 #define elf_section__for_each_rel(reldata, pos, pos_mem, idx, nr_entries) \
380         for (idx = 0, pos = gelf_getrel(reldata, 0, &pos_mem); \
381              idx < nr_entries; \
382              ++idx, pos = gelf_getrel(reldata, idx, &pos_mem))
383 
384 #define elf_section__for_each_rela(reldata, pos, pos_mem, idx, nr_entries) \
385         for (idx = 0, pos = gelf_getrela(reldata, 0, &pos_mem); \
386              idx < nr_entries; \
387              ++idx, pos = gelf_getrela(reldata, idx, &pos_mem))
388 
389 /*
390  * We need to check if we have a .dynsym, so that we can handle the
391  * .plt, synthesizing its symbols, that aren't on the symtabs (be it
392  * .dynsym or .symtab).
393  * And always look at the original dso, not at debuginfo packages, that
394  * have the PLT data stripped out (shdr_rel_plt.sh_type == SHT_NOBITS).
395  */
396 static int dso__synthesize_plt_symbols(struct  dso *self, int v)
397 {
398         uint32_t nr_rel_entries, idx;
399         GElf_Sym sym;
400         u64 plt_offset;
401         GElf_Shdr shdr_plt;
402         struct symbol *f;
403         GElf_Shdr shdr_rel_plt, shdr_dynsym;
404         Elf_Data *reldata, *syms, *symstrs;
405         Elf_Scn *scn_plt_rel, *scn_symstrs, *scn_dynsym;
406         size_t dynsym_idx;
407         GElf_Ehdr ehdr;
408         char sympltname[1024];
409         Elf *elf;
410         int nr = 0, symidx, fd, err = 0;
411 
412         fd = open(self->name, O_RDONLY);
413         if (fd < 0)
414                 goto out;
415 
416         elf = elf_begin(fd, PERF_ELF_C_READ_MMAP, NULL);
417         if (elf == NULL)
418                 goto out_close;
419 
420         if (gelf_getehdr(elf, &ehdr) == NULL)
421                 goto out_elf_end;
422 
423         scn_dynsym = elf_section_by_name(elf, &ehdr, &shdr_dynsym,
424                                          ".dynsym", &dynsym_idx);
425         if (scn_dynsym == NULL)
426                 goto out_elf_end;
427 
428         scn_plt_rel = elf_section_by_name(elf, &ehdr, &shdr_rel_plt,
429                                           ".rela.plt", NULL);
430         if (scn_plt_rel == NULL) {
431                 scn_plt_rel = elf_section_by_name(elf, &ehdr, &shdr_rel_plt,
432                                                   ".rel.plt", NULL);
433                 if (scn_plt_rel == NULL)
434                         goto out_elf_end;
435         }
436 
437         err = -1;
438 
439         if (shdr_rel_plt.sh_link != dynsym_idx)
440                 goto out_elf_end;
441 
442         if (elf_section_by_name(elf, &ehdr, &shdr_plt, ".plt", NULL) == NULL)
443                 goto out_elf_end;
444 
445         /*
446          * Fetch the relocation section to find the idxes to the GOT
447          * and the symbols in the .dynsym they refer to.
448          */
449         reldata = elf_getdata(scn_plt_rel, NULL);
450         if (reldata == NULL)
451                 goto out_elf_end;
452 
453         syms = elf_getdata(scn_dynsym, NULL);
454         if (syms == NULL)
455                 goto out_elf_end;
456 
457         scn_symstrs = elf_getscn(elf, shdr_dynsym.sh_link);
458         if (scn_symstrs == NULL)
459                 goto out_elf_end;
460 
461         symstrs = elf_getdata(scn_symstrs, NULL);
462         if (symstrs == NULL)
463                 goto out_elf_end;
464 
465         nr_rel_entries = shdr_rel_plt.sh_size / shdr_rel_plt.sh_entsize;
466         plt_offset = shdr_plt.sh_offset;
467 
468         if (shdr_rel_plt.sh_type == SHT_RELA) {
469                 GElf_Rela pos_mem, *pos;
470 
471                 elf_section__for_each_rela(reldata, pos, pos_mem, idx,
472                                            nr_rel_entries) {
473                         symidx = GELF_R_SYM(pos->r_info);
474                         plt_offset += shdr_plt.sh_entsize;
475                         gelf_getsym(syms, symidx, &sym);
476                         snprintf(sympltname, sizeof(sympltname),
477                                  "%s@plt", elf_sym__name(&sym, symstrs));
478 
479                         f = symbol__new(plt_offset, shdr_plt.sh_entsize,
480                                         sympltname, self->sym_priv_size, 0, v);
481                         if (!f)
482                                 goto out_elf_end;
483 
484                         dso__insert_symbol(self, f);
485                         ++nr;
486                 }
487         } else if (shdr_rel_plt.sh_type == SHT_REL) {
488                 GElf_Rel pos_mem, *pos;
489                 elf_section__for_each_rel(reldata, pos, pos_mem, idx,
490                                           nr_rel_entries) {
491                         symidx = GELF_R_SYM(pos->r_info);
492                         plt_offset += shdr_plt.sh_entsize;
493                         gelf_getsym(syms, symidx, &sym);
494                         snprintf(sympltname, sizeof(sympltname),
495                                  "%s@plt", elf_sym__name(&sym, symstrs));
496 
497                         f = symbol__new(plt_offset, shdr_plt.sh_entsize,
498                                         sympltname, self->sym_priv_size, 0, v);
499                         if (!f)
500                                 goto out_elf_end;
501 
502                         dso__insert_symbol(self, f);
503                         ++nr;
504                 }
505         }
506 
507         err = 0;
508 out_elf_end:
509         elf_end(elf);
510 out_close:
511         close(fd);
512 
513         if (err == 0)
514                 return nr;
515 out:
516         fprintf(stderr, "%s: problems reading %s PLT info.\n",
517                 __func__, self->name);
518         return 0;
519 }
520 
521 static int dso__load_sym(struct dso *self, int fd, const char *name,
522                          symbol_filter_t filter, int v, struct module *mod)
523 {
524         Elf_Data *symstrs, *secstrs;
525         uint32_t nr_syms;
526         int err = -1;
527         uint32_t idx;
528         GElf_Ehdr ehdr;
529         GElf_Shdr shdr;
530         Elf_Data *syms;
531         GElf_Sym sym;
532         Elf_Scn *sec, *sec_strndx;
533         Elf *elf;
534         int nr = 0, kernel = !strcmp("[kernel]", self->name);
535 
536         elf = elf_begin(fd, PERF_ELF_C_READ_MMAP, NULL);
537         if (elf == NULL) {
538                 if (v)
539                         fprintf(stderr, "%s: cannot read %s ELF file.\n",
540                                 __func__, name);
541                 goto out_close;
542         }
543 
544         if (gelf_getehdr(elf, &ehdr) == NULL) {
545                 if (v)
546                         fprintf(stderr, "%s: cannot get elf header.\n", __func__);
547                 goto out_elf_end;
548         }
549 
550         sec = elf_section_by_name(elf, &ehdr, &shdr, ".symtab", NULL);
551         if (sec == NULL) {
552                 sec = elf_section_by_name(elf, &ehdr, &shdr, ".dynsym", NULL);
553                 if (sec == NULL)
554                         goto out_elf_end;
555         }
556 
557         syms = elf_getdata(sec, NULL);
558         if (syms == NULL)
559                 goto out_elf_end;
560 
561         sec = elf_getscn(elf, shdr.sh_link);
562         if (sec == NULL)
563                 goto out_elf_end;
564 
565         symstrs = elf_getdata(sec, NULL);
566         if (symstrs == NULL)
567                 goto out_elf_end;
568 
569         sec_strndx = elf_getscn(elf, ehdr.e_shstrndx);
570         if (sec_strndx == NULL)
571                 goto out_elf_end;
572 
573         secstrs = elf_getdata(sec_strndx, NULL);
574         if (secstrs == NULL)
575                 goto out_elf_end;
576 
577         nr_syms = shdr.sh_size / shdr.sh_entsize;
578 
579         memset(&sym, 0, sizeof(sym));
580         if (!kernel) {
581                 self->adjust_symbols = (ehdr.e_type == ET_EXEC ||
582                                 elf_section_by_name(elf, &ehdr, &shdr,
583                                                      ".gnu.prelink_undo",
584                                                      NULL) != NULL);
585         } else self->adjust_symbols = 0;
586 
587         elf_symtab__for_each_symbol(syms, nr_syms, idx, sym) {
588                 struct symbol *f;
589                 const char *elf_name;
590                 char *demangled;
591                 u64 obj_start;
592                 struct section *section = NULL;
593                 int is_label = elf_sym__is_label(&sym);
594                 const char *section_name;
595 
596                 if (!is_label && !elf_sym__is_function(&sym))
597                         continue;
598 
599                 sec = elf_getscn(elf, sym.st_shndx);
600                 if (!sec)
601                         goto out_elf_end;
602 
603                 gelf_getshdr(sec, &shdr);
604 
605                 if (is_label && !elf_sec__is_text(&shdr, secstrs))
606                         continue;
607 
608                 section_name = elf_sec__name(&shdr, secstrs);
609                 obj_start = sym.st_value;
610 
611                 if (self->adjust_symbols) {
612                         if (v >= 2)
613                                 printf("adjusting symbol: st_value: %Lx sh_addr: %Lx sh_offset: %Lx\n",
614                                         (u64)sym.st_value, (u64)shdr.sh_addr, (u64)shdr.sh_offset);
615 
616                         sym.st_value -= shdr.sh_addr - shdr.sh_offset;
617                 }
618 
619                 if (mod) {
620                         section = mod->sections->find_section(mod->sections, section_name);
621                         if (section)
622                                 sym.st_value += section->vma;
623                         else {
624                                 fprintf(stderr, "dso__load_sym() module %s lookup of %s failed\n",
625                                         mod->name, section_name);
626                                 goto out_elf_end;
627                         }
628                 }
629                 /*
630                  * We need to figure out if the object was created from C++ sources
631                  * DWARF DW_compile_unit has this, but we don't always have access
632                  * to it...
633                  */
634                 elf_name = elf_sym__name(&sym, symstrs);
635                 demangled = bfd_demangle(NULL, elf_name, DMGL_PARAMS | DMGL_ANSI);
636                 if (demangled != NULL)
637                         elf_name = demangled;
638 
639                 f = symbol__new(sym.st_value, sym.st_size, elf_name,
640                                 self->sym_priv_size, obj_start, v);
641                 free(demangled);
642                 if (!f)
643                         goto out_elf_end;
644 
645                 if (filter && filter(self, f))
646                         symbol__delete(f, self->sym_priv_size);
647                 else {
648                         f->module = mod;
649                         dso__insert_symbol(self, f);
650                         nr++;
651                 }
652         }
653 
654         err = nr;
655 out_elf_end:
656         elf_end(elf);
657 out_close:
658         return err;
659 }
660 
661 #define BUILD_ID_SIZE 128
662 
663 static char *dso__read_build_id(struct dso *self, int v)
664 {
665         int i;
666         GElf_Ehdr ehdr;
667         GElf_Shdr shdr;
668         Elf_Data *build_id_data;
669         Elf_Scn *sec;
670         char *build_id = NULL, *bid;
671         unsigned char *raw;
672         Elf *elf;
673         int fd = open(self->name, O_RDONLY);
674 
675         if (fd < 0)
676                 goto out;
677 
678         elf = elf_begin(fd, PERF_ELF_C_READ_MMAP, NULL);
679         if (elf == NULL) {
680                 if (v)
681                         fprintf(stderr, "%s: cannot read %s ELF file.\n",
682                                 __func__, self->name);
683                 goto out_close;
684         }
685 
686         if (gelf_getehdr(elf, &ehdr) == NULL) {
687                 if (v)
688                         fprintf(stderr, "%s: cannot get elf header.\n", __func__);
689                 goto out_elf_end;
690         }
691 
692         sec = elf_section_by_name(elf, &ehdr, &shdr, ".note.gnu.build-id", NULL);
693         if (sec == NULL)
694                 goto out_elf_end;
695 
696         build_id_data = elf_getdata(sec, NULL);
697         if (build_id_data == NULL)
698                 goto out_elf_end;
699         build_id = malloc(BUILD_ID_SIZE);
700         if (build_id == NULL)
701                 goto out_elf_end;
702         raw = build_id_data->d_buf + 16;
703         bid = build_id;
704 
705         for (i = 0; i < 20; ++i) {
706                 sprintf(bid, "%02x", *raw);
707                 ++raw;
708                 bid += 2;
709         }
710         if (v >= 2)
711                 printf("%s(%s): %s\n", __func__, self->name, build_id);
712 out_elf_end:
713         elf_end(elf);
714 out_close:
715         close(fd);
716 out:
717         return build_id;
718 }
719 
720 char dso__symtab_origin(const struct dso *self)
721 {
722         static const char origin[] = {
723                 [DSO__ORIG_KERNEL] =   'k',
724                 [DSO__ORIG_JAVA_JIT] = 'j',
725                 [DSO__ORIG_FEDORA] =   'f',
726                 [DSO__ORIG_UBUNTU] =   'u',
727                 [DSO__ORIG_BUILDID] =  'b',
728                 [DSO__ORIG_DSO] =      'd',
729         };
730 
731         if (self == NULL || self->origin == DSO__ORIG_NOT_FOUND)
732                 return '!';
733         return origin[self->origin];
734 }
735 
736 int dso__load(struct dso *self, symbol_filter_t filter, int v)
737 {
738         int size = PATH_MAX;
739         char *name = malloc(size), *build_id = NULL;
740         int ret = -1;
741         int fd;
742 
743         if (!name)
744                 return -1;
745 
746         self->adjust_symbols = 0;
747 
748         if (strncmp(self->name, "/tmp/perf-", 10) == 0) {
749                 ret = dso__load_perf_map(self, filter, v);
750                 self->origin = ret > 0 ? DSO__ORIG_JAVA_JIT :
751                                          DSO__ORIG_NOT_FOUND;
752                 return ret;
753         }
754 
755         self->origin = DSO__ORIG_FEDORA - 1;
756 
757 more:
758         do {
759                 self->origin++;
760                 switch (self->origin) {
761                 case DSO__ORIG_FEDORA:
762                         snprintf(name, size, "/usr/lib/debug%s.debug", self->name);
763                         break;
764                 case DSO__ORIG_UBUNTU:
765                         snprintf(name, size, "/usr/lib/debug%s", self->name);
766                         break;
767                 case DSO__ORIG_BUILDID:
768                         build_id = dso__read_build_id(self, v);
769                         if (build_id != NULL) {
770                                 snprintf(name, size,
771                                          "/usr/lib/debug/.build-id/%.2s/%s.debug",
772                                         build_id, build_id + 2);
773                                 free(build_id);
774                                 break;
775                         }
776                         self->origin++;
777                         /* Fall thru */
778                 case DSO__ORIG_DSO:
779                         snprintf(name, size, "%s", self->name);
780                         break;
781 
782                 default:
783                         goto out;
784                 }
785 
786                 fd = open(name, O_RDONLY);
787         } while (fd < 0);
788 
789         ret = dso__load_sym(self, fd, name, filter, v, NULL);
790         close(fd);
791 
792         /*
793          * Some people seem to have debuginfo files _WITHOUT_ debug info!?!?
794          */
795         if (!ret)
796                 goto more;
797 
798         if (ret > 0) {
799                 int nr_plt = dso__synthesize_plt_symbols(self, v);
800                 if (nr_plt > 0)
801                         ret += nr_plt;
802         }
803 out:
804         free(name);
805         if (ret < 0 && strstr(self->name, " (deleted)") != NULL)
806                 return 0;
807         return ret;
808 }
809 
810 static int dso__load_module(struct dso *self, struct mod_dso *mods, const char *name,
811                              symbol_filter_t filter, int v)
812 {
813         struct module *mod = mod_dso__find_module(mods, name);
814         int err = 0, fd;
815 
816         if (mod == NULL || !mod->active)
817                 return err;
818 
819         fd = open(mod->path, O_RDONLY);
820 
821         if (fd < 0)
822                 return err;
823 
824         err = dso__load_sym(self, fd, name, filter, v, mod);
825         close(fd);
826 
827         return err;
828 }
829 
830 int dso__load_modules(struct dso *self, symbol_filter_t filter, int v)
831 {
832         struct mod_dso *mods = mod_dso__new_dso("modules");
833         struct module *pos;
834         struct rb_node *next;
835         int err, count = 0;
836 
837         err = mod_dso__load_modules(mods);
838 
839         if (err <= 0)
840                 return err;
841 
842         /*
843          * Iterate over modules, and load active symbols.
844          */
845         next = rb_first(&mods->mods);
846         while (next) {
847                 pos = rb_entry(next, struct module, rb_node);
848                 err = dso__load_module(self, mods, pos->name, filter, v);
849 
850                 if (err < 0)
851                         break;
852 
853                 next = rb_next(&pos->rb_node);
854                 count += err;
855         }
856 
857         if (err < 0) {
858                 mod_dso__delete_modules(mods);
859                 mod_dso__delete_self(mods);
860                 return err;
861         }
862 
863         return count;
864 }
865 
866 static inline void dso__fill_symbol_holes(struct dso *self)
867 {
868         struct symbol *prev = NULL;
869         struct rb_node *nd;
870 
871         for (nd = rb_last(&self->syms); nd; nd = rb_prev(nd)) {
872                 struct symbol *pos = rb_entry(nd, struct symbol, rb_node);
873 
874                 if (prev) {
875                         u64 hole = 0;
876                         int alias = pos->start == prev->start;
877 
878                         if (!alias)
879                                 hole = prev->start - pos->end - 1;
880 
881                         if (hole || alias) {
882                                 if (alias)
883                                         pos->end = prev->end;
884                                 else if (hole)
885                                         pos->end = prev->start - 1;
886                         }
887                 }
888                 prev = pos;
889         }
890 }
891 
892 static int dso__load_vmlinux(struct dso *self, const char *vmlinux,
893                              symbol_filter_t filter, int v)
894 {
895         int err, fd = open(vmlinux, O_RDONLY);
896 
897         if (fd < 0)
898                 return -1;
899 
900         err = dso__load_sym(self, fd, vmlinux, filter, v, NULL);
901 
902         if (err > 0)
903                 dso__fill_symbol_holes(self);
904 
905         close(fd);
906 
907         return err;
908 }
909 
910 int dso__load_kernel(struct dso *self, const char *vmlinux,
911                      symbol_filter_t filter, int v, int use_modules)
912 {
913         int err = -1;
914 
915         if (vmlinux) {
916                 err = dso__load_vmlinux(self, vmlinux, filter, v);
917                 if (err > 0 && use_modules) {
918                         int syms = dso__load_modules(self, filter, v);
919 
920                         if (syms < 0) {
921                                 fprintf(stderr, "dso__load_modules failed!\n");
922                                 return syms;
923                         }
924                         err += syms;
925                 }
926         }
927 
928         if (err <= 0)
929                 err = dso__load_kallsyms(self, filter, v);
930 
931         if (err > 0)
932                 self->origin = DSO__ORIG_KERNEL;
933 
934         return err;
935 }
936 
937 LIST_HEAD(dsos);
938 struct dso      *kernel_dso;
939 struct dso      *vdso;
940 struct dso      *hypervisor_dso;
941 
942 const char      *vmlinux_name = "vmlinux";
943 int             modules;
944 
945 static void dsos__add(struct dso *dso)
946 {
947         list_add_tail(&dso->node, &dsos);
948 }
949 
950 static struct dso *dsos__find(const char *name)
951 {
952         struct dso *pos;
953 
954         list_for_each_entry(pos, &dsos, node)
955                 if (strcmp(pos->name, name) == 0)
956                         return pos;
957         return NULL;
958 }
959 
960 struct dso *dsos__findnew(const char *name)
961 {
962         struct dso *dso = dsos__find(name);
963         int nr;
964 
965         if (dso)
966                 return dso;
967 
968         dso = dso__new(name, 0);
969         if (!dso)
970                 goto out_delete_dso;
971 
972         nr = dso__load(dso, NULL, verbose);
973         if (nr < 0) {
974                 eprintf("Failed to open: %s\n", name);
975                 goto out_delete_dso;
976         }
977         if (!nr)
978                 eprintf("No symbols found in: %s, maybe install a debug package?\n", name);
979 
980         dsos__add(dso);
981 
982         return dso;
983 
984 out_delete_dso:
985         dso__delete(dso);
986         return NULL;
987 }
988 
989 void dsos__fprintf(FILE *fp)
990 {
991         struct dso *pos;
992 
993         list_for_each_entry(pos, &dsos, node)
994                 dso__fprintf(pos, fp);
995 }
996 
997 static struct symbol *vdso__find_symbol(struct dso *dso, u64 ip)
998 {
999         return dso__find_symbol(dso, ip);
1000 }
1001 
1002 int load_kernel(void)
1003 {
1004         int err;
1005 
1006         kernel_dso = dso__new("[kernel]", 0);
1007         if (!kernel_dso)
1008                 return -1;
1009 
1010         err = dso__load_kernel(kernel_dso, vmlinux_name, NULL, verbose, modules);
1011         if (err <= 0) {
1012                 dso__delete(kernel_dso);
1013                 kernel_dso = NULL;
1014         } else
1015                 dsos__add(kernel_dso);
1016 
1017         vdso = dso__new("[vdso]", 0);
1018         if (!vdso)
1019                 return -1;
1020 
1021         vdso->find_symbol = vdso__find_symbol;
1022 
1023         dsos__add(vdso);
1024 
1025         hypervisor_dso = dso__new("[hypervisor]", 0);
1026         if (!hypervisor_dso)
1027                 return -1;
1028         dsos__add(hypervisor_dso);
1029 
1030         return err;
1031 }
1032 
1033 
1034 void symbol__init(void)
1035 {
1036         elf_version(EV_CURRENT);
1037 }
1038 

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