On 10/05/16 10:40, He Kuang wrote:
> 32-bit programs can be run on 64-bit machines, so we should choose
> unwind methods according to 'thread->map' instead of the host
> architecture.
>
> This patch adds methods to test whether a dso is 64-bit or 32-bit by
> the class info in elf.
What about using dso->is_64_bit set by dso__load_sym() ?
>
> Signed-off-by: He Kuang <heku...@huawei.com>
> ---
> tools/perf/util/symbol-elf.c | 16 +++++++++++++++
> tools/perf/util/symbol.c | 49
> ++++++++++++++++++++++++++++++++++++++++++++
> tools/perf/util/symbol.h | 2 ++
> 3 files changed, 67 insertions(+)
>
> diff --git a/tools/perf/util/symbol-elf.c b/tools/perf/util/symbol-elf.c
> index 3f9d679..9f290b9 100644
> --- a/tools/perf/util/symbol-elf.c
> +++ b/tools/perf/util/symbol-elf.c
> @@ -636,6 +636,22 @@ bool __weak elf__needs_adjust_symbols(GElf_Ehdr ehdr)
> return ehdr.e_type == ET_EXEC || ehdr.e_type == ET_REL;
> }
>
> +int elf_is_64_bit(char *name)
> +{
> + Elf *elf;
> + int fd;
> +
> + fd = open(name, O_RDONLY);
> + if (fd < 0)
> + return -1;
> +
> + elf = elf_begin(fd, PERF_ELF_C_READ_MMAP, NULL);
> + if (elf == NULL)
> + return -1;
> +
> + return (gelf_getclass(elf) == ELFCLASS64);
> +}
> +
> int symsrc__init(struct symsrc *ss, struct dso *dso, const char *name,
> enum dso_binary_type type)
> {
> diff --git a/tools/perf/util/symbol.c b/tools/perf/util/symbol.c
> index 4630751..592bf8c 100644
> --- a/tools/perf/util/symbol.c
> +++ b/tools/perf/util/symbol.c
> @@ -1395,6 +1395,55 @@ static bool dso__is_compatible_symtab_type(struct dso
> *dso, bool kmod,
> }
> }
>
> +int dso_is_64_bit(struct dso *dso, struct map *map)
> +{
> + char *name;
> + u_int i;
> + bool kmod;
> + char *root_dir = (char *) "";
> + struct machine *machine;
> +
> + if (map->groups && map->groups->machine)
> + machine = map->groups->machine;
> + else
> + machine = NULL;
> +
> + if (machine)
> + root_dir = machine->root_dir;
> +
> + name = malloc(PATH_MAX);
> + if (!name)
> + return -1;
> +
> + kmod = dso->symtab_type == DSO_BINARY_TYPE__SYSTEM_PATH_KMODULE ||
> + dso->symtab_type == DSO_BINARY_TYPE__SYSTEM_PATH_KMODULE_COMP ||
> + dso->symtab_type == DSO_BINARY_TYPE__GUEST_KMODULE ||
> + dso->symtab_type == DSO_BINARY_TYPE__GUEST_KMODULE_COMP;
> +
> + /*
> + * Iterate over candidate debug images.
> + * Keep track of "interesting" ones (those which have a symtab, dynsym,
> + * and/or opd section) for processing.
> + */
> + for (i = 0; i < DSO_BINARY_TYPE__SYMTAB_CNT; i++) {
> + enum dso_binary_type symtab_type = binary_type_symtab[i];
> +
> + if (!dso__is_compatible_symtab_type(dso, kmod, symtab_type))
> + continue;
> +
> + if (dso__read_binary_type_filename(dso, symtab_type,
> + root_dir, name, PATH_MAX))
> + continue;
> +
> + if (!is_regular_file(name))
> + continue;
> +
> + return elf_is_64_bit(name);
> + }
> +
> + return -1;
> +}
> +
> int dso__load(struct dso *dso, struct map *map, symbol_filter_t filter)
> {
> char *name;
> diff --git a/tools/perf/util/symbol.h b/tools/perf/util/symbol.h
> index 4e6910e..d33fbf4 100644
> --- a/tools/perf/util/symbol.h
> +++ b/tools/perf/util/symbol.h
> @@ -308,6 +308,8 @@ int setup_list(struct strlist **list, const char
> *list_str,
> const char *list_name);
> int setup_intlist(struct intlist **list, const char *list_str,
> const char *list_name);
> +int elf_is_64_bit(char *name);
> +int dso_is_64_bit(struct dso *dso, struct map *map);
>
> #ifdef HAVE_LIBELF_SUPPORT
> bool elf__needs_adjust_symbols(GElf_Ehdr ehdr);
>
