Commit-ID: 8e0cf965f95edd41df11cca50b92b4cb6ea8d80a Gitweb: http://git.kernel.org/tip/8e0cf965f95edd41df11cca50b92b4cb6ea8d80a Author: Adrian Hunter <adrian.hun...@intel.com> AuthorDate: Wed, 7 Aug 2013 14:38:51 +0300 Committer: Arnaldo Carvalho de Melo <a...@redhat.com> CommitDate: Wed, 7 Aug 2013 17:35:33 -0300
perf symbols: Add support for reading from /proc/kcore In the absence of vmlinux, perf tools uses kallsyms for symbols. If the user has access, now also map to /proc/kcore. The dso data_type is now set to either DSO_BINARY_TYPE__KCORE or DSO_BINARY_TYPE__GUEST_KCORE as approprite. This patch breaks the "vmlinux symtab matches kallsyms" test. That is fixed in a following patch. Signed-off-by: Adrian Hunter <adrian.hun...@intel.com> Cc: David Ahern <dsah...@gmail.com> Cc: Frederic Weisbecker <fweis...@gmail.com> Cc: Ingo Molnar <mi...@kernel.org> Cc: Jiri Olsa <jo...@redhat.com> Cc: Mike Galbraith <efa...@gmx.de> Cc: Namhyung Kim <namhy...@gmail.com> Cc: Paul Mackerras <pau...@samba.org> Cc: Peter Zijlstra <pet...@infradead.org> Cc: Stephane Eranian <eran...@google.com> Link: http://lkml.kernel.org/r/1375875537-4509-8-git-send-email-adrian.hun...@intel.com Signed-off-by: Arnaldo Carvalho de Melo <a...@redhat.com> --- tools/perf/util/dso.c | 5 + tools/perf/util/dso.h | 8 ++ tools/perf/util/machine.c | 16 +++ tools/perf/util/map.c | 18 ++++ tools/perf/util/map.h | 13 +++ tools/perf/util/symbol-elf.c | 51 +++++++++ tools/perf/util/symbol-minimal.c | 7 ++ tools/perf/util/symbol.c | 227 ++++++++++++++++++++++++++++++++++++++- tools/perf/util/symbol.h | 5 + 9 files changed, 347 insertions(+), 3 deletions(-) diff --git a/tools/perf/util/dso.c b/tools/perf/util/dso.c index 1955804..e3c1ff8 100644 --- a/tools/perf/util/dso.c +++ b/tools/perf/util/dso.c @@ -95,6 +95,11 @@ int dso__binary_type_file(struct dso *dso, enum dso_binary_type type, dso->long_name); break; + case DSO_BINARY_TYPE__KCORE: + case DSO_BINARY_TYPE__GUEST_KCORE: + snprintf(file, size, "%s", dso->long_name); + break; + default: case DSO_BINARY_TYPE__KALLSYMS: case DSO_BINARY_TYPE__GUEST_KALLSYMS: diff --git a/tools/perf/util/dso.h b/tools/perf/util/dso.h index 735a837..b793053 100644 --- a/tools/perf/util/dso.h +++ b/tools/perf/util/dso.h @@ -21,6 +21,8 @@ enum dso_binary_type { DSO_BINARY_TYPE__SYSTEM_PATH_DSO, DSO_BINARY_TYPE__GUEST_KMODULE, DSO_BINARY_TYPE__SYSTEM_PATH_KMODULE, + DSO_BINARY_TYPE__KCORE, + DSO_BINARY_TYPE__GUEST_KCORE, DSO_BINARY_TYPE__NOT_FOUND, }; @@ -155,4 +157,10 @@ static inline bool dso__is_vmlinux(struct dso *dso) dso->data_type == DSO_BINARY_TYPE__GUEST_VMLINUX; } +static inline bool dso__is_kcore(struct dso *dso) +{ + return dso->data_type == DSO_BINARY_TYPE__KCORE || + dso->data_type == DSO_BINARY_TYPE__GUEST_KCORE; +} + #endif /* __PERF_DSO */ diff --git a/tools/perf/util/machine.c b/tools/perf/util/machine.c index dc35dcf..ef3b49c 100644 --- a/tools/perf/util/machine.c +++ b/tools/perf/util/machine.c @@ -856,6 +856,18 @@ static void machine__set_kernel_mmap_len(struct machine *machine, } } +static bool machine__uses_kcore(struct machine *machine) +{ + struct dso *dso; + + list_for_each_entry(dso, &machine->kernel_dsos, node) { + if (dso__is_kcore(dso)) + return true; + } + + return false; +} + static int machine__process_kernel_mmap_event(struct machine *machine, union perf_event *event) { @@ -864,6 +876,10 @@ static int machine__process_kernel_mmap_event(struct machine *machine, enum dso_kernel_type kernel_type; bool is_kernel_mmap; + /* If we have maps from kcore then we do not need or want any others */ + if (machine__uses_kcore(machine)) + return 0; + machine__mmap_name(machine, kmmap_prefix, sizeof(kmmap_prefix)); if (machine__is_host(machine)) kernel_type = DSO_TYPE_KERNEL; diff --git a/tools/perf/util/map.c b/tools/perf/util/map.c index 4d599fe..9e8304c 100644 --- a/tools/perf/util/map.c +++ b/tools/perf/util/map.c @@ -555,3 +555,21 @@ struct map *maps__find(struct rb_root *maps, u64 ip) return NULL; } + +struct map *maps__first(struct rb_root *maps) +{ + struct rb_node *first = rb_first(maps); + + if (first) + return rb_entry(first, struct map, rb_node); + return NULL; +} + +struct map *maps__next(struct map *map) +{ + struct rb_node *next = rb_next(&map->rb_node); + + if (next) + return rb_entry(next, struct map, rb_node); + return NULL; +} diff --git a/tools/perf/util/map.h b/tools/perf/util/map.h index a887f2c..2cc93cb 100644 --- a/tools/perf/util/map.h +++ b/tools/perf/util/map.h @@ -112,6 +112,8 @@ size_t __map_groups__fprintf_maps(struct map_groups *mg, void maps__insert(struct rb_root *maps, struct map *map); void maps__remove(struct rb_root *maps, struct map *map); struct map *maps__find(struct rb_root *maps, u64 addr); +struct map *maps__first(struct rb_root *maps); +struct map *maps__next(struct map *map); void map_groups__init(struct map_groups *mg); void map_groups__exit(struct map_groups *mg); int map_groups__clone(struct map_groups *mg, @@ -139,6 +141,17 @@ static inline struct map *map_groups__find(struct map_groups *mg, return maps__find(&mg->maps[type], addr); } +static inline struct map *map_groups__first(struct map_groups *mg, + enum map_type type) +{ + return maps__first(&mg->maps[type]); +} + +static inline struct map *map_groups__next(struct map *map) +{ + return maps__next(map); +} + struct symbol *map_groups__find_symbol(struct map_groups *mg, enum map_type type, u64 addr, struct map **mapp, diff --git a/tools/perf/util/symbol-elf.c b/tools/perf/util/symbol-elf.c index 3eaa7b4..a7b9ab5 100644 --- a/tools/perf/util/symbol-elf.c +++ b/tools/perf/util/symbol-elf.c @@ -951,6 +951,57 @@ out_elf_end: return err; } +static int elf_read_maps(Elf *elf, bool exe, mapfn_t mapfn, void *data) +{ + GElf_Phdr phdr; + size_t i, phdrnum; + int err; + u64 sz; + + if (elf_getphdrnum(elf, &phdrnum)) + return -1; + + for (i = 0; i < phdrnum; i++) { + if (gelf_getphdr(elf, i, &phdr) == NULL) + return -1; + if (phdr.p_type != PT_LOAD) + continue; + if (exe) { + if (!(phdr.p_flags & PF_X)) + continue; + } else { + if (!(phdr.p_flags & PF_R)) + continue; + } + sz = min(phdr.p_memsz, phdr.p_filesz); + if (!sz) + continue; + err = mapfn(phdr.p_vaddr, sz, phdr.p_offset, data); + if (err) + return err; + } + return 0; +} + +int file__read_maps(int fd, bool exe, mapfn_t mapfn, void *data, + bool *is_64_bit) +{ + int err; + Elf *elf; + + elf = elf_begin(fd, PERF_ELF_C_READ_MMAP, NULL); + if (elf == NULL) + return -1; + + if (is_64_bit) + *is_64_bit = (gelf_getclass(elf) == ELFCLASS64); + + err = elf_read_maps(elf, exe, mapfn, data); + + elf_end(elf); + return err; +} + void symbol__elf_init(void) { elf_version(EV_CURRENT); diff --git a/tools/perf/util/symbol-minimal.c b/tools/perf/util/symbol-minimal.c index a7390cd..3a802c3 100644 --- a/tools/perf/util/symbol-minimal.c +++ b/tools/perf/util/symbol-minimal.c @@ -301,6 +301,13 @@ int dso__load_sym(struct dso *dso, struct map *map __maybe_unused, return 0; } +int file__read_maps(int fd __maybe_unused, bool exe __maybe_unused, + mapfn_t mapfn __maybe_unused, void *data __maybe_unused, + bool *is_64_bit __maybe_unused) +{ + return -1; +} + void symbol__elf_init(void) { } diff --git a/tools/perf/util/symbol.c b/tools/perf/util/symbol.c index b9056a8..77f3b95 100644 --- a/tools/perf/util/symbol.c +++ b/tools/perf/util/symbol.c @@ -327,6 +327,16 @@ static struct symbol *symbols__find(struct rb_root *symbols, u64 ip) return NULL; } +static struct symbol *symbols__first(struct rb_root *symbols) +{ + struct rb_node *n = rb_first(symbols); + + if (n) + return rb_entry(n, struct symbol, rb_node); + + return NULL; +} + struct symbol_name_rb_node { struct rb_node rb_node; struct symbol sym; @@ -397,6 +407,11 @@ struct symbol *dso__find_symbol(struct dso *dso, return symbols__find(&dso->symbols[type], addr); } +struct symbol *dso__first_symbol(struct dso *dso, enum map_type type) +{ + return symbols__first(&dso->symbols[type]); +} + struct symbol *dso__find_symbol_by_name(struct dso *dso, enum map_type type, const char *name) { @@ -533,6 +548,53 @@ static int dso__load_all_kallsyms(struct dso *dso, const char *filename, return kallsyms__parse(filename, &args, map__process_kallsym_symbol); } +static int dso__split_kallsyms_for_kcore(struct dso *dso, struct map *map, + symbol_filter_t filter) +{ + struct map_groups *kmaps = map__kmap(map)->kmaps; + struct map *curr_map; + struct symbol *pos; + int count = 0, moved = 0; + struct rb_root *root = &dso->symbols[map->type]; + struct rb_node *next = rb_first(root); + + while (next) { + char *module; + + pos = rb_entry(next, struct symbol, rb_node); + next = rb_next(&pos->rb_node); + + module = strchr(pos->name, '\t'); + if (module) + *module = '\0'; + + curr_map = map_groups__find(kmaps, map->type, pos->start); + + if (!curr_map || (filter && filter(curr_map, pos))) { + rb_erase(&pos->rb_node, root); + symbol__delete(pos); + } else { + pos->start -= curr_map->start - curr_map->pgoff; + if (pos->end) + pos->end -= curr_map->start - curr_map->pgoff; + if (curr_map != map) { + rb_erase(&pos->rb_node, root); + symbols__insert( + &curr_map->dso->symbols[curr_map->type], + pos); + ++moved; + } else { + ++count; + } + } + } + + /* Symbols have been adjusted */ + dso->adjust_symbols = 1; + + return count + moved; +} + /* * Split the symbols into maps, making sure there are no overlaps, i.e. the * kernel range is broken in several maps, named [kernel].N, as we don't have @@ -674,6 +736,161 @@ bool symbol__restricted_filename(const char *filename, return restricted; } +struct kcore_mapfn_data { + struct dso *dso; + enum map_type type; + struct list_head maps; +}; + +static int kcore_mapfn(u64 start, u64 len, u64 pgoff, void *data) +{ + struct kcore_mapfn_data *md = data; + struct map *map; + + map = map__new2(start, md->dso, md->type); + if (map == NULL) + return -ENOMEM; + + map->end = map->start + len; + map->pgoff = pgoff; + + list_add(&map->node, &md->maps); + + return 0; +} + +/* + * If kallsyms is referenced by name then we look for kcore in the same + * directory. + */ +static bool kcore_filename_from_kallsyms_filename(char *kcore_filename, + const char *kallsyms_filename) +{ + char *name; + + strcpy(kcore_filename, kallsyms_filename); + name = strrchr(kcore_filename, '/'); + if (!name) + return false; + + if (!strcmp(name, "/kallsyms")) { + strcpy(name, "/kcore"); + return true; + } + + return false; +} + +static int dso__load_kcore(struct dso *dso, struct map *map, + const char *kallsyms_filename) +{ + struct map_groups *kmaps = map__kmap(map)->kmaps; + struct machine *machine = kmaps->machine; + struct kcore_mapfn_data md; + struct map *old_map, *new_map, *replacement_map = NULL; + bool is_64_bit; + int err, fd; + char kcore_filename[PATH_MAX]; + struct symbol *sym; + + /* This function requires that the map is the kernel map */ + if (map != machine->vmlinux_maps[map->type]) + return -EINVAL; + + if (!kcore_filename_from_kallsyms_filename(kcore_filename, + kallsyms_filename)) + return -EINVAL; + + md.dso = dso; + md.type = map->type; + INIT_LIST_HEAD(&md.maps); + + fd = open(kcore_filename, O_RDONLY); + if (fd < 0) + return -EINVAL; + + /* Read new maps into temporary lists */ + err = file__read_maps(fd, md.type == MAP__FUNCTION, kcore_mapfn, &md, + &is_64_bit); + if (err) + goto out_err; + + if (list_empty(&md.maps)) { + err = -EINVAL; + goto out_err; + } + + /* Remove old maps */ + old_map = map_groups__first(kmaps, map->type); + while (old_map) { + struct map *next = map_groups__next(old_map); + + if (old_map != map) + map_groups__remove(kmaps, old_map); + old_map = next; + } + + /* Find the kernel map using the first symbol */ + sym = dso__first_symbol(dso, map->type); + list_for_each_entry(new_map, &md.maps, node) { + if (sym && sym->start >= new_map->start && + sym->start < new_map->end) { + replacement_map = new_map; + break; + } + } + + if (!replacement_map) + replacement_map = list_entry(md.maps.next, struct map, node); + + /* Add new maps */ + while (!list_empty(&md.maps)) { + new_map = list_entry(md.maps.next, struct map, node); + list_del(&new_map->node); + if (new_map == replacement_map) { + map->start = new_map->start; + map->end = new_map->end; + map->pgoff = new_map->pgoff; + map->map_ip = new_map->map_ip; + map->unmap_ip = new_map->unmap_ip; + map__delete(new_map); + /* Ensure maps are correctly ordered */ + map_groups__remove(kmaps, map); + map_groups__insert(kmaps, map); + } else { + map_groups__insert(kmaps, new_map); + } + } + + /* + * Set the data type and long name so that kcore can be read via + * dso__data_read_addr(). + */ + if (dso->kernel == DSO_TYPE_GUEST_KERNEL) + dso->data_type = DSO_BINARY_TYPE__GUEST_KCORE; + else + dso->data_type = DSO_BINARY_TYPE__KCORE; + dso__set_long_name(dso, strdup(kcore_filename)); + + close(fd); + + if (map->type == MAP__FUNCTION) + pr_debug("Using %s for kernel object code\n", kcore_filename); + else + pr_debug("Using %s for kernel data\n", kcore_filename); + + return 0; + +out_err: + while (!list_empty(&md.maps)) { + map = list_entry(md.maps.next, struct map, node); + list_del(&map->node); + map__delete(map); + } + close(fd); + return -EINVAL; +} + int dso__load_kallsyms(struct dso *dso, const char *filename, struct map *map, symbol_filter_t filter) { @@ -691,7 +908,10 @@ int dso__load_kallsyms(struct dso *dso, const char *filename, else dso->symtab_type = DSO_BINARY_TYPE__KALLSYMS; - return dso__split_kallsyms(dso, map, filter); + if (!dso__load_kcore(dso, map, filename)) + return dso__split_kallsyms_for_kcore(dso, map, filter); + else + return dso__split_kallsyms(dso, map, filter); } static int dso__load_perf_map(struct dso *dso, struct map *map, @@ -1065,7 +1285,7 @@ do_kallsyms: pr_debug("Using %s for symbols\n", kallsyms_filename); free(kallsyms_allocated_filename); - if (err > 0) { + if (err > 0 && !dso__is_kcore(dso)) { dso__set_long_name(dso, strdup("[kernel.kallsyms]")); map__fixup_start(map); map__fixup_end(map); @@ -1109,8 +1329,9 @@ static int dso__load_guest_kernel_sym(struct dso *dso, struct map *map, } err = dso__load_kallsyms(dso, kallsyms_filename, map, filter); - if (err > 0) { + if (err > 0) pr_debug("Using %s for symbols\n", kallsyms_filename); + if (err > 0 && !dso__is_kcore(dso)) { machine__mmap_name(machine, path, sizeof(path)); dso__set_long_name(dso, strdup(path)); map__fixup_start(map); diff --git a/tools/perf/util/symbol.h b/tools/perf/util/symbol.h index 5f720dc..fd5b70e 100644 --- a/tools/perf/util/symbol.h +++ b/tools/perf/util/symbol.h @@ -215,6 +215,7 @@ struct symbol *dso__find_symbol(struct dso *dso, enum map_type type, u64 addr); struct symbol *dso__find_symbol_by_name(struct dso *dso, enum map_type type, const char *name); +struct symbol *dso__first_symbol(struct dso *dso, enum map_type type); int filename__read_build_id(const char *filename, void *bf, size_t size); int sysfs__read_build_id(const char *filename, void *bf, size_t size); @@ -247,4 +248,8 @@ void symbols__fixup_duplicate(struct rb_root *symbols); void symbols__fixup_end(struct rb_root *symbols); void __map_groups__fixup_end(struct map_groups *mg, enum map_type type); +typedef int (*mapfn_t)(u64 start, u64 len, u64 pgoff, void *data); +int file__read_maps(int fd, bool exe, mapfn_t mapfn, void *data, + bool *is_64_bit); + #endif /* __PERF_SYMBOL */ -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
