xref: /linux/tools/perf/util/symbol.c (revision af901ca181d92aac3a7dc265144a9081a86d8f39)
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