Re: [PATCH] perf tools: Synthesize GROUP_DESC feature in pipe mode

[Stephane Eranian]

Hi Jiri,
On Thu, Jul 12, 2018 at 6:52 AM Jiri Olsa <jolsa@xxxxxxxxxx> wrote:
>
> Stephan reported, that pipe mode does not carry the group
> information and thus the piped report won't display the
> grouped output for following command:
>
Thanks for fixing this quickly.
I think we should have more testing on the pipe mode, in general.

>   # perf record -e '{cycles,instructions,branches}' -a sleep 4 | perf report
>
> It has no idea about the group setup, so it will display
> events separately:
>
>   # Overhead  Command          Shared Object             ...
>   # ........  ...............  .......................
>   #
>        6.71%  swapper          [kernel.kallsyms]
>        2.28%  offlineimap      libpython2.7.so.1.0
>        0.78%  perf             [kernel.kallsyms]
>   ...
>
> Fixing GROUP_DESC feature record to be synthesized in pipe mode,
> so the report output is grouped if there's group defined in record:
>
>   #                 Overhead  Command          Shared    ...
>   # ........................  ...............  .......
>   #
>        7.57%   0.16%   0.30%  swapper          [kernel
>        1.87%   3.15%   2.46%  offlineimap      libpyth
>        1.33%   0.00%   0.00%  perf             [kernel
>   ...
>
> Cc: David Carrillo-Cisneros <davidcc@xxxxxxxxxx>
> Reported-by: Stephane Eranian <eranian@xxxxxxxxxx>
> Link: http://lkml.kernel.org/n/tip-ybqyh8ac4g173iy3xt4pxnlo@xxxxxxxxxxxxxx
> Signed-off-by: Jiri Olsa <jolsa@xxxxxxxxxx>
> ---
>  tools/perf/util/header.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/tools/perf/util/header.c b/tools/perf/util/header.c
> index 59fcc790c865..af9aaf28f976 100644
> --- a/tools/perf/util/header.c
> +++ b/tools/perf/util/header.c
> @@ -2587,7 +2587,7 @@ static const struct feature_ops feat_ops[HEADER_LAST_FEATURE] = {
>         FEAT_OPR(NUMA_TOPOLOGY, numa_topology,  true),
>         FEAT_OPN(BRANCH_STACK,  branch_stack,   false),
>         FEAT_OPR(PMU_MAPPINGS,  pmu_mappings,   false),
> -       FEAT_OPN(GROUP_DESC,    group_desc,     false),
> +       FEAT_OPR(GROUP_DESC,    group_desc,     false),
>         FEAT_OPN(AUXTRACE,      auxtrace,       false),
>         FEAT_OPN(STAT,          stat,           false),
>         FEAT_OPN(CACHE,         cache,          true),
> --
> 2.17.1
>