Re: [PATCH 2/5] perf unwind: Do not look at globals

From: Jiri Olsa
Date: Tue Jan 16 2018 - 10:19:27 EST


On Tue, Jan 16, 2018 at 11:24:35AM -0300, Arnaldo Carvalho de Melo wrote:

SNIP

> Cc: Adrian Hunter <adrian.hunter@xxxxxxxxx>
> Cc: David Ahern <dsahern@xxxxxxxxx>
> Cc: Hendrick Brueckner <brueckner@xxxxxxxxxxxxxxxxxx>
> Cc: Jiri Olsa <jolsa@xxxxxxxxxx>
> Cc: Namhyung Kim <namhyung@xxxxxxxxxx>
> Cc: Thomas Richter <tmricht@xxxxxxxxxxxxxxxxxx>
> Cc: Wang Nan <wangnan0@xxxxxxxxxx>
> Link: https://lkml.kernel.org/n/tip-skbth8ufepbtw8xar7gdsb6l@xxxxxxxxxxxxxx
> Signed-off-by: Arnaldo Carvalho de Melo <acme@xxxxxxxxxx>
> ---
> tools/perf/util/unwind-libunwind-local.c | 9 ---------
> 1 file changed, 9 deletions(-)
>
> diff --git a/tools/perf/util/unwind-libunwind-local.c b/tools/perf/util/unwind-libunwind-local.c
> index 7a42f703e858..02dc5a9d8f72 100644
> --- a/tools/perf/util/unwind-libunwind-local.c
> +++ b/tools/perf/util/unwind-libunwind-local.c
> @@ -631,9 +631,6 @@ static unw_accessors_t accessors = {
>
> static int _unwind__prepare_access(struct thread *thread)
> {
> - if (callchain_param.record_mode != CALLCHAIN_DWARF)
> - return 0;
> -

this would create thread->addr_space also for data without
dwarf callchains data, so I think we need to keep it

it should get set in apply_config_terms which calls parse_callchain_record
once it detects some 'call-graph' term setup.. something's probably wrong
there?

jirka

> thread->addr_space = unw_create_addr_space(&accessors, 0);
> if (!thread->addr_space) {
> pr_err("unwind: Can't create unwind address space.\n");
> @@ -646,17 +643,11 @@ static int _unwind__prepare_access(struct thread *thread)
>
> static void _unwind__flush_access(struct thread *thread)
> {
> - if (callchain_param.record_mode != CALLCHAIN_DWARF)
> - return;
> -
> unw_flush_cache(thread->addr_space, 0, 0);
> }
>
> static void _unwind__finish_access(struct thread *thread)
> {
> - if (callchain_param.record_mode != CALLCHAIN_DWARF)
> - return;
> -
> unw_destroy_addr_space(thread->addr_space);
> }
>
> --
> 2.14.3
>