From mboxrd@z Thu Jan  1 00:00:00 1970
From: Namhyung Kim <namhyung@kernel.org>
Subject: Re: [PATCHSET 0/9] perf: Improve cgroup profiling (v3)
Date: Tue, 24 Dec 2019 09:40:04 +0900
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To: Vince Weaver <vincent.weaver@maine.edu>
Cc: Ingo Molnar <mingo@kernel.org>, Peter Zijlstra <a.p.zijlstra@chello.nl>, Arnaldo Carvalho de Melo <acme@kernel.org>, Jiri Olsa <jolsa@redhat.com>, Alexander Shishkin <alexander.shishkin@linux.intel.com>, Mark Rutland <mark.rutland@arm.com>, Stephane Eranian <eranian@google.com>, LKML <linux-kernel@vger.kernel.org>, linux-perf-users <linux-perf-users@vger.kernel.org>, Tejun Heo <tj@kernel.org>, Li Zefan <lizefan@huawei.com>, Johannes Weiner <hannes@cmpxchg.org>, Adrian Hunter <adrian.hunter@intel.com>
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Hi Vince,

On Tue, Dec 24, 2019 at 2:35 AM Vince Weaver <vincent.weaver@maine.edu> wrote:
>
> On Mon, 23 Dec 2019, Namhyung Kim wrote:
>
> > This work is to improve cgroup profiling in perf.  Currently it only
> > supports profiling tasks in a specific cgroup and there's no way to
> > identify which cgroup the current sample belongs to.  So I added
> > PERF_SAMPLE_CGROUP to add cgroup id into each sample.  It's a 64-bit
> > integer having file handle of the cgroup.  And kernel also generates
> > PERF_RECORD_CGROUP event for new groups to correlate the cgroup id and
> > cgroup name (path in the cgroup filesystem).  The cgroup id can be
> > read from userspace by name_to_handle_at() system call so it can
> > synthesize the CGROUP event for existing groups.
>
> so is there a patch to the manpage that describes this new behavior in
> perf_event_open()?

Not yet.  I'll cook a patch once it's merged to the Linus' tree.

Thanks
Namhyung