Re: [PATCH 7/9] perf tools: Pass build_id object to dso__build_id_equal

[Ian Rogers]

On Wed, Sep 30, 2020 at 10:15 AM Jiri Olsa <jolsa@xxxxxxxxxx> wrote:
>
> Passing build_id object to dso__build_id_equal, so we can
> properly check build id with different size than sha1.
>
> Signed-off-by: Jiri Olsa <jolsa@xxxxxxxxxx>

Acked-by: Ian Rogers <irogers@xxxxxxxxxx>

Thanks,
Ian

> ---
>  tools/perf/util/dso.c        | 5 +++--
>  tools/perf/util/dso.h        | 2 +-
>  tools/perf/util/symbol-elf.c | 8 ++++++--
>  tools/perf/util/symbol.c     | 2 +-
>  4 files changed, 11 insertions(+), 6 deletions(-)
>
> diff --git a/tools/perf/util/dso.c b/tools/perf/util/dso.c
> index 4415ce83150b..ca965845b35e 100644
> --- a/tools/perf/util/dso.c
> +++ b/tools/perf/util/dso.c
> @@ -1332,9 +1332,10 @@ void dso__set_build_id(struct dso *dso, struct build_id *bid)
>         dso->has_build_id = 1;
>  }
>
> -bool dso__build_id_equal(const struct dso *dso, u8 *build_id)
> +bool dso__build_id_equal(const struct dso *dso, struct build_id *bid)
>  {
> -       return memcmp(dso->bid.data, build_id, sizeof(dso->bid.data)) == 0;
> +       return dso->bid.size == bid->size &&
> +              memcmp(dso->bid.data, bid->data, dso->bid.size) == 0;
>  }
>
>  void dso__read_running_kernel_build_id(struct dso *dso, struct machine *machine)
> diff --git a/tools/perf/util/dso.h b/tools/perf/util/dso.h
> index 5a5678dbdaa5..f926c96bf230 100644
> --- a/tools/perf/util/dso.h
> +++ b/tools/perf/util/dso.h
> @@ -261,7 +261,7 @@ void dso__set_sorted_by_name(struct dso *dso);
>  void dso__sort_by_name(struct dso *dso);
>
>  void dso__set_build_id(struct dso *dso, struct build_id *bid);
> -bool dso__build_id_equal(const struct dso *dso, u8 *build_id);
> +bool dso__build_id_equal(const struct dso *dso, struct build_id *bid);
>  void dso__read_running_kernel_build_id(struct dso *dso,
>                                        struct machine *machine);
>  int dso__kernel_module_get_build_id(struct dso *dso, const char *root_dir);
> diff --git a/tools/perf/util/symbol-elf.c b/tools/perf/util/symbol-elf.c
> index 97a55f162ea5..44dd86a4f25f 100644
> --- a/tools/perf/util/symbol-elf.c
> +++ b/tools/perf/util/symbol-elf.c
> @@ -834,13 +834,17 @@ int symsrc__init(struct symsrc *ss, struct dso *dso, const char *name,
>         /* Always reject images with a mismatched build-id: */
>         if (dso->has_build_id && !symbol_conf.ignore_vmlinux_buildid) {
>                 u8 build_id[BUILD_ID_SIZE];
> +               struct build_id bid;
> +               int size;
>
> -               if (elf_read_build_id(elf, build_id, BUILD_ID_SIZE) < 0) {
> +               size = elf_read_build_id(elf, build_id, BUILD_ID_SIZE);
> +               if (size <= 0) {
>                         dso->load_errno = DSO_LOAD_ERRNO__CANNOT_READ_BUILDID;
>                         goto out_elf_end;
>                 }
>
> -               if (!dso__build_id_equal(dso, build_id)) {
> +               build_id__init(&bid, build_id, size);
> +               if (!dso__build_id_equal(dso, &bid)) {
>                         pr_debug("%s: build id mismatch for %s.\n", __func__, name);
>                         dso->load_errno = DSO_LOAD_ERRNO__MISMATCHING_BUILDID;
>                         goto out_elf_end;
> diff --git a/tools/perf/util/symbol.c b/tools/perf/util/symbol.c
> index 976632d0baa0..6138866665df 100644
> --- a/tools/perf/util/symbol.c
> +++ b/tools/perf/util/symbol.c
> @@ -2136,7 +2136,7 @@ static char *dso__find_kallsyms(struct dso *dso, struct map *map)
>         }
>
>         if (sysfs__read_build_id("/sys/kernel/notes", &bid) == 0)
> -               is_host = dso__build_id_equal(dso, bid.data);
> +               is_host = dso__build_id_equal(dso, &bid);
>
>         /* Try a fast path for /proc/kallsyms if possible */
>         if (is_host) {
> --
> 2.26.2
>