Re: [PATCH v5] perf stat: Enable BPF counter with --for-each-cgroup

[Song Liu]

> On Jul 1, 2021, at 2:12 PM, Namhyung Kim <namhyung@xxxxxxxxxx> wrote:
> 
> Recently bperf was added to use BPF to count perf events for various
> purposes.  This is an extension for the approach and targetting to
> cgroup usages.
> 
> Unlike the other bperf, it doesn't share the events with other
> processes but it'd reduce unnecessary events (and the overhead of
> multiplexing) for each monitored cgroup within the perf session.
> 
> When --for-each-cgroup is used with --bpf-counters, it will open
> cgroup-switches event per cpu internally and attach the new BPF
> program to read given perf_events and to aggregate the results for
> cgroups.  It's only called when task is switched to a task in a
> different cgroup.
> 
> Cc: Song Liu <songliubraving@xxxxxx>
> Signed-off-by: Namhyung Kim <namhyung@xxxxxxxxxx>

Acked-by: Song Liu <songliubraving@xxxxxx>