Re: [RFC PATCH 2/2] perf: Filter events based on perf-namespace

[Aravinda Prasad]

On Monday 27 June 2016 09:20 PM, Peter Zijlstra wrote:
> On Tue, Jun 14, 2016 at 10:19:51PM +0530, Aravinda Prasad wrote:
>> Whenever perf tool is executed inside a container, this
>> patch restricts the events to the perf-namespace in which
>> the perf tool is executing.
>>
>> This patch is based on the existing support available
>> for tracing with cgroups.
>>
>> TODO:
>>     - Avoid code duplication.
> 
> Can't you, at perf_event_open() time, convert a per-cpu event into a
> per-cpu-per-cgroup event for these namespace thingies?
> 
> That seems to immediately and completely remove all that duplication.

Sorry for the delay in the response.

I was looking into a way how a per-cpu event can be converted to
per-cpu-per-cgroup event at perf_event_open() but could not figure out
how to do this conversion. The cgroup event expects the fd of the cgroup
directory in cgroupfs and in this case we don't have any fd passed in.
Not sure if I am missing anything.

-- 
Regards,
Aravinda