diff options
Diffstat (limited to 'tools/perf/util/symbol.c')
-rw-r--r-- | tools/perf/util/symbol.c | 407 |
1 files changed, 337 insertions, 70 deletions
diff --git a/tools/perf/util/symbol.c b/tools/perf/util/symbol.c index 86e1437..16ddca2 100644 --- a/tools/perf/util/symbol.c +++ b/tools/perf/util/symbol.c @@ -7,8 +7,23 @@ #include <gelf.h> #include <elf.h> +#ifndef NO_DEMANGLE +#include <bfd.h> +#else +static inline +char *bfd_demangle(void __used *v, const char __used *c, int __used i) +{ + return NULL; +} +#endif + const char *sym_hist_filter; +#ifndef DMGL_PARAMS +#define DMGL_PARAMS (1 << 0) /* Include function args */ +#define DMGL_ANSI (1 << 1) /* Include const, volatile, etc */ +#endif + static struct symbol *symbol__new(u64 start, u64 len, const char *name, unsigned int priv_size, u64 obj_start, int verbose) @@ -35,7 +50,7 @@ static struct symbol *symbol__new(u64 start, u64 len, self = ((void *)self) + priv_size; } self->start = start; - self->end = start + len - 1; + self->end = len ? start + len - 1 : start; memcpy(self->name, name, namelen); return self; @@ -48,8 +63,12 @@ static void symbol__delete(struct symbol *self, unsigned int priv_size) static size_t symbol__fprintf(struct symbol *self, FILE *fp) { - return fprintf(fp, " %llx-%llx %s\n", + if (!self->module) + return fprintf(fp, " %llx-%llx %s\n", self->start, self->end, self->name); + else + return fprintf(fp, " %llx-%llx %s \t[%s]\n", + self->start, self->end, self->name, self->module->name); } struct dso *dso__new(const char *name, unsigned int sym_priv_size) @@ -61,6 +80,7 @@ struct dso *dso__new(const char *name, unsigned int sym_priv_size) self->syms = RB_ROOT; self->sym_priv_size = sym_priv_size; self->find_symbol = dso__find_symbol; + self->slen_calculated = 0; } return self; @@ -146,6 +166,7 @@ static int dso__load_kallsyms(struct dso *self, symbol_filter_t filter, int verb char *line = NULL; size_t n; FILE *file = fopen("/proc/kallsyms", "r"); + int count = 0; if (file == NULL) goto out_failure; @@ -188,8 +209,10 @@ static int dso__load_kallsyms(struct dso *self, symbol_filter_t filter, int verb if (filter && filter(self, sym)) symbol__delete(sym, self->sym_priv_size); - else + else { dso__insert_symbol(self, sym); + count++; + } } /* @@ -212,7 +235,7 @@ static int dso__load_kallsyms(struct dso *self, symbol_filter_t filter, int verb free(line); fclose(file); - return 0; + return count; out_delete_line: free(line); @@ -307,6 +330,26 @@ static inline int elf_sym__is_function(const GElf_Sym *sym) sym->st_size != 0; } +static inline int elf_sym__is_label(const GElf_Sym *sym) +{ + return elf_sym__type(sym) == STT_NOTYPE && + sym->st_name != 0 && + sym->st_shndx != SHN_UNDEF && + sym->st_shndx != SHN_ABS; +} + +static inline const char *elf_sec__name(const GElf_Shdr *shdr, + const Elf_Data *secstrs) +{ + return secstrs->d_buf + shdr->sh_name; +} + +static inline int elf_sec__is_text(const GElf_Shdr *shdr, + const Elf_Data *secstrs) +{ + return strstr(elf_sec__name(shdr, secstrs), "text") != NULL; +} + static inline const char *elf_sym__name(const GElf_Sym *sym, const Elf_Data *symstrs) { @@ -346,36 +389,61 @@ static Elf_Scn *elf_section_by_name(Elf *elf, GElf_Ehdr *ep, idx < nr_entries; \ ++idx, pos = gelf_getrela(reldata, idx, &pos_mem)) -static int dso__synthesize_plt_symbols(struct dso *self, Elf *elf, - GElf_Ehdr *ehdr, Elf_Scn *scn_dynsym, - GElf_Shdr *shdr_dynsym, - size_t dynsym_idx, int verbose) +/* + * We need to check if we have a .dynsym, so that we can handle the + * .plt, synthesizing its symbols, that aren't on the symtabs (be it + * .dynsym or .symtab). + * And always look at the original dso, not at debuginfo packages, that + * have the PLT data stripped out (shdr_rel_plt.sh_type == SHT_NOBITS). + */ +static int dso__synthesize_plt_symbols(struct dso *self, int verbose) { uint32_t nr_rel_entries, idx; GElf_Sym sym; u64 plt_offset; GElf_Shdr shdr_plt; struct symbol *f; - GElf_Shdr shdr_rel_plt; + GElf_Shdr shdr_rel_plt, shdr_dynsym; Elf_Data *reldata, *syms, *symstrs; - Elf_Scn *scn_plt_rel, *scn_symstrs; + Elf_Scn *scn_plt_rel, *scn_symstrs, *scn_dynsym; + size_t dynsym_idx; + GElf_Ehdr ehdr; char sympltname[1024]; - int nr = 0, symidx; + Elf *elf; + int nr = 0, symidx, fd, err = 0; + + fd = open(self->name, O_RDONLY); + if (fd < 0) + goto out; + + elf = elf_begin(fd, ELF_C_READ_MMAP, NULL); + if (elf == NULL) + goto out_close; + + if (gelf_getehdr(elf, &ehdr) == NULL) + goto out_elf_end; + + scn_dynsym = elf_section_by_name(elf, &ehdr, &shdr_dynsym, + ".dynsym", &dynsym_idx); + if (scn_dynsym == NULL) + goto out_elf_end; - scn_plt_rel = elf_section_by_name(elf, ehdr, &shdr_rel_plt, + scn_plt_rel = elf_section_by_name(elf, &ehdr, &shdr_rel_plt, ".rela.plt", NULL); if (scn_plt_rel == NULL) { - scn_plt_rel = elf_section_by_name(elf, ehdr, &shdr_rel_plt, + scn_plt_rel = elf_section_by_name(elf, &ehdr, &shdr_rel_plt, ".rel.plt", NULL); if (scn_plt_rel == NULL) - return 0; + goto out_elf_end; } + err = -1; + if (shdr_rel_plt.sh_link != dynsym_idx) - return 0; + goto out_elf_end; - if (elf_section_by_name(elf, ehdr, &shdr_plt, ".plt", NULL) == NULL) - return 0; + if (elf_section_by_name(elf, &ehdr, &shdr_plt, ".plt", NULL) == NULL) + goto out_elf_end; /* * Fetch the relocation section to find the indexes to the GOT @@ -383,19 +451,19 @@ static int dso__synthesize_plt_symbols(struct dso *self, Elf *elf, */ reldata = elf_getdata(scn_plt_rel, NULL); if (reldata == NULL) - return -1; + goto out_elf_end; syms = elf_getdata(scn_dynsym, NULL); if (syms == NULL) - return -1; + goto out_elf_end; - scn_symstrs = elf_getscn(elf, shdr_dynsym->sh_link); + scn_symstrs = elf_getscn(elf, shdr_dynsym.sh_link); if (scn_symstrs == NULL) - return -1; + goto out_elf_end; symstrs = elf_getdata(scn_symstrs, NULL); if (symstrs == NULL) - return -1; + goto out_elf_end; nr_rel_entries = shdr_rel_plt.sh_size / shdr_rel_plt.sh_entsize; plt_offset = shdr_plt.sh_offset; @@ -414,7 +482,7 @@ static int dso__synthesize_plt_symbols(struct dso *self, Elf *elf, f = symbol__new(plt_offset, shdr_plt.sh_entsize, sympltname, self->sym_priv_size, 0, verbose); if (!f) - return -1; + goto out_elf_end; dso__insert_symbol(self, f); ++nr; @@ -432,25 +500,31 @@ static int dso__synthesize_plt_symbols(struct dso *self, Elf *elf, f = symbol__new(plt_offset, shdr_plt.sh_entsize, sympltname, self->sym_priv_size, 0, verbose); if (!f) - return -1; + goto out_elf_end; dso__insert_symbol(self, f); ++nr; } - } else { - /* - * TODO: There are still one more shdr_rel_plt.sh_type - * I have to investigate, but probably should be ignored. - */ } - return nr; + err = 0; +out_elf_end: + elf_end(elf); +out_close: + close(fd); + + if (err == 0) + return nr; +out: + fprintf(stderr, "%s: problems reading %s PLT info.\n", + __func__, self->name); + return 0; } static int dso__load_sym(struct dso *self, int fd, const char *name, - symbol_filter_t filter, int verbose) + symbol_filter_t filter, int verbose, struct module *mod) { - Elf_Data *symstrs; + Elf_Data *symstrs, *secstrs; uint32_t nr_syms; int err = -1; uint32_t index; @@ -458,10 +532,9 @@ static int dso__load_sym(struct dso *self, int fd, const char *name, GElf_Shdr shdr; Elf_Data *syms; GElf_Sym sym; - Elf_Scn *sec, *sec_dynsym; + Elf_Scn *sec, *sec_strndx; Elf *elf; - size_t dynsym_idx; - int nr = 0; + int nr = 0, kernel = !strcmp("[kernel]", self->name); elf = elf_begin(fd, ELF_C_READ_MMAP, NULL); if (elf == NULL) { @@ -477,32 +550,11 @@ static int dso__load_sym(struct dso *self, int fd, const char *name, goto out_elf_end; } - /* - * We need to check if we have a .dynsym, so that we can handle the - * .plt, synthesizing its symbols, that aren't on the symtabs (be it - * .dynsym or .symtab) - */ - sec_dynsym = elf_section_by_name(elf, &ehdr, &shdr, - ".dynsym", &dynsym_idx); - if (sec_dynsym != NULL) { - nr = dso__synthesize_plt_symbols(self, elf, &ehdr, - sec_dynsym, &shdr, - dynsym_idx, verbose); - if (nr < 0) - goto out_elf_end; - } - - /* - * But if we have a full .symtab (that is a superset of .dynsym) we - * should add the symbols not in the .dynsyn - */ sec = elf_section_by_name(elf, &ehdr, &shdr, ".symtab", NULL); if (sec == NULL) { - if (sec_dynsym == NULL) + sec = elf_section_by_name(elf, &ehdr, &shdr, ".dynsym", NULL); + if (sec == NULL) goto out_elf_end; - - sec = sec_dynsym; - gelf_getshdr(sec, &shdr); } syms = elf_getdata(sec, NULL); @@ -517,15 +569,34 @@ static int dso__load_sym(struct dso *self, int fd, const char *name, if (symstrs == NULL) goto out_elf_end; + sec_strndx = elf_getscn(elf, ehdr.e_shstrndx); + if (sec_strndx == NULL) + goto out_elf_end; + + secstrs = elf_getdata(sec_strndx, NULL); + if (secstrs == NULL) + goto out_elf_end; + nr_syms = shdr.sh_size / shdr.sh_entsize; memset(&sym, 0, sizeof(sym)); + if (!kernel) { + self->adjust_symbols = (ehdr.e_type == ET_EXEC || + elf_section_by_name(elf, &ehdr, &shdr, + ".gnu.prelink_undo", + NULL) != NULL); + } else self->adjust_symbols = 0; elf_symtab__for_each_symbol(syms, nr_syms, index, sym) { struct symbol *f; + const char *name; + char *demangled; u64 obj_start; + struct section *section = NULL; + int is_label = elf_sym__is_label(&sym); + const char *section_name; - if (!elf_sym__is_function(&sym)) + if (!is_label && !elf_sym__is_function(&sym)) continue; sec = elf_getscn(elf, sym.st_shndx); @@ -533,19 +604,51 @@ static int dso__load_sym(struct dso *self, int fd, const char *name, goto out_elf_end; gelf_getshdr(sec, &shdr); + + if (is_label && !elf_sec__is_text(&shdr, secstrs)) + continue; + + section_name = elf_sec__name(&shdr, secstrs); obj_start = sym.st_value; - sym.st_value -= shdr.sh_addr - shdr.sh_offset; + if (self->adjust_symbols) { + if (verbose >= 2) + printf("adjusting symbol: st_value: %Lx sh_addr: %Lx sh_offset: %Lx\n", + (u64)sym.st_value, (u64)shdr.sh_addr, (u64)shdr.sh_offset); + + sym.st_value -= shdr.sh_addr - shdr.sh_offset; + } - f = symbol__new(sym.st_value, sym.st_size, - elf_sym__name(&sym, symstrs), + if (mod) { + section = mod->sections->find_section(mod->sections, section_name); + if (section) + sym.st_value += section->vma; + else { + fprintf(stderr, "dso__load_sym() module %s lookup of %s failed\n", + mod->name, section_name); + goto out_elf_end; + } + } + /* + * We need to figure out if the object was created from C++ sources + * DWARF DW_compile_unit has this, but we don't always have access + * to it... + */ + name = elf_sym__name(&sym, symstrs); + demangled = bfd_demangle(NULL, name, DMGL_PARAMS | DMGL_ANSI); + if (demangled != NULL) + name = demangled; + + f = symbol__new(sym.st_value, sym.st_size, name, self->sym_priv_size, obj_start, verbose); + free(demangled); if (!f) goto out_elf_end; if (filter && filter(self, f)) symbol__delete(f, self->sym_priv_size); else { + f->module = mod; dso__insert_symbol(self, f); nr++; } @@ -558,10 +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; @@ -569,6 +731,8 @@ int dso__load(struct dso *self, symbol_filter_t filter, int verbose) if (!name) return -1; + self->adjust_symbols = 0; + if (strncmp(self->name, "/tmp/perf-", 10) == 0) return dso__load_perf_map(self, filter, verbose); @@ -581,7 +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; @@ -593,7 +768,7 @@ more: fd = open(name, O_RDONLY); } while (fd < 0); - ret = dso__load_sym(self, fd, name, filter, verbose); + ret = dso__load_sym(self, fd, name, filter, verbose, NULL); close(fd); /* @@ -602,11 +777,96 @@ more: if (!ret) goto more; + if (ret > 0) { + int nr_plt = dso__synthesize_plt_symbols(self, verbose); + if (nr_plt > 0) + ret += nr_plt; + } out: free(name); return ret; } +static int dso__load_module(struct dso *self, struct mod_dso *mods, const char *name, + symbol_filter_t filter, int verbose) +{ + struct module *mod = mod_dso__find_module(mods, name); + int err = 0, fd; + + if (mod == NULL || !mod->active) + return err; + + fd = open(mod->path, O_RDONLY); + + if (fd < 0) + return err; + + err = dso__load_sym(self, fd, name, filter, verbose, mod); + close(fd); + + return err; +} + +int dso__load_modules(struct dso *self, symbol_filter_t filter, int verbose) +{ + struct mod_dso *mods = mod_dso__new_dso("modules"); + struct module *pos; + struct rb_node *next; + int err; + + err = mod_dso__load_modules(mods); + + if (err <= 0) + return err; + + /* + * Iterate over modules, and load active symbols. + */ + next = rb_first(&mods->mods); + while (next) { + pos = rb_entry(next, struct module, rb_node); + err = dso__load_module(self, mods, pos->name, filter, verbose); + + if (err < 0) + break; + + next = rb_next(&pos->rb_node); + } + + if (err < 0) { + mod_dso__delete_modules(mods); + mod_dso__delete_self(mods); + } + + return err; +} + +static inline void dso__fill_symbol_holes(struct dso *self) +{ + struct symbol *prev = NULL; + struct rb_node *nd; + + for (nd = rb_last(&self->syms); nd; nd = rb_prev(nd)) { + struct symbol *pos = rb_entry(nd, struct symbol, rb_node); + + if (prev) { + u64 hole = 0; + int alias = pos->start == prev->start; + + if (!alias) + hole = prev->start - pos->end - 1; + + if (hole || alias) { + if (alias) + pos->end = prev->end; + else if (hole) + pos->end = prev->start - 1; + } + } + prev = pos; + } +} + static int dso__load_vmlinux(struct dso *self, const char *vmlinux, symbol_filter_t filter, int verbose) { @@ -615,21 +875,28 @@ static int dso__load_vmlinux(struct dso *self, const char *vmlinux, if (fd < 0) return -1; - err = dso__load_sym(self, fd, vmlinux, filter, verbose); + err = dso__load_sym(self, fd, vmlinux, filter, verbose, NULL); + + if (err > 0) + dso__fill_symbol_holes(self); + close(fd); return err; } int dso__load_kernel(struct dso *self, const char *vmlinux, - symbol_filter_t filter, int verbose) + symbol_filter_t filter, int verbose, int modules) { int err = -1; - if (vmlinux) + if (vmlinux) { err = dso__load_vmlinux(self, vmlinux, filter, verbose); + if (err > 0 && modules) + err = dso__load_modules(self, filter, verbose); + } - if (err) + if (err <= 0) err = dso__load_kallsyms(self, filter, verbose); return err; |