diff options
| -rw-r--r-- | tools/perf/util/symbol.c | 76 |
1 files changed, 73 insertions, 3 deletions
diff --git a/tools/perf/util/symbol.c b/tools/perf/util/symbol.c index 0580b94785e..16ddca20294 100644 --- a/tools/perf/util/symbol.c +++ b/tools/perf/util/symbol.c @@ -661,10 +661,69 @@ out_close: return err; } +#define BUILD_ID_SIZE 128 + +static char *dso__read_build_id(struct dso *self, int verbose) +{ + int i; + GElf_Ehdr ehdr; + GElf_Shdr shdr; + Elf_Data *build_id_data; + Elf_Scn *sec; + char *build_id = NULL, *bid; + unsigned char *raw; + Elf *elf; + int fd = open(self->name, O_RDONLY); + + if (fd < 0) + goto out; + + elf = elf_begin(fd, ELF_C_READ_MMAP, NULL); + if (elf == NULL) { + if (verbose) + fprintf(stderr, "%s: cannot read %s ELF file.\n", + __func__, self->name); + goto out_close; + } + + if (gelf_getehdr(elf, &ehdr) == NULL) { + if (verbose) + fprintf(stderr, "%s: cannot get elf header.\n", __func__); + goto out_elf_end; + } + + sec = elf_section_by_name(elf, &ehdr, &shdr, ".note.gnu.build-id", NULL); + if (sec == NULL) + goto out_elf_end; + + build_id_data = elf_getdata(sec, NULL); + if (build_id_data == NULL) + goto out_elf_end; + build_id = malloc(BUILD_ID_SIZE); + if (build_id == NULL) + goto out_elf_end; + raw = build_id_data->d_buf + 16; + bid = build_id; + + for (i = 0; i < 20; ++i) { + sprintf(bid, "%02x", *raw); + ++raw; + bid += 2; + } + if (verbose) + printf("%s(%s): %s\n", __func__, self->name, build_id); +out_elf_end: + elf_end(elf); +out_close: + close(fd); +out: + return build_id; +} + int dso__load(struct dso *self, symbol_filter_t filter, int verbose) { - int size = strlen(self->name) + sizeof("/usr/lib/debug%s.debug"); - char *name = malloc(size); + int size = PATH_MAX; + char *name = malloc(size), *build_id = NULL; int variant = 0; int ret = -1; int fd; @@ -686,7 +745,18 @@ more: case 1: /* Ubuntu */ snprintf(name, size, "/usr/lib/debug%s", self->name); break; - case 2: /* Sane people */ + case 2: + build_id = dso__read_build_id(self, verbose); + if (build_id != NULL) { + snprintf(name, size, + "/usr/lib/debug/.build-id/%.2s/%s.debug", + build_id, build_id + 2); + free(build_id); + break; + } + variant++; + /* Fall thru */ + case 3: /* Sane people */ snprintf(name, size, "%s", self->name); break; |