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Date:   Mon, 7 Sep 2020 12:02:24 +0100
From:   Qais Yousef <qais.yousef@arm.com>
To:     Phil Auld <pauld@redhat.com>
Cc:     Dietmar Eggemann <dietmar.eggemann@arm.com>,
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        vincent.guittot@linaro.org, linux-kernel@vger.kernel.org,
        valentin.schneider@arm.com
Subject: Re: [PATCH v2] sched/debug: Add new tracepoint to track cpu_capacity
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On 09/02/20 09:54, Phil Auld wrote:
> > 
> > I think this decoupling is not necessary. The natural place for those
> > scheduler trace_event based on trace_points extension files is
> > kernel/sched/ and here the internal sched.h can just be included.
> > 
> > If someone really wants to build this as an out-of-tree module there is
> > an easy way to make kernel/sched/sched.h visible.
> >
> 
> It's not so much that we really _want_ to do this in an external module.
> But we aren't adding more trace events and my (limited) knowledge of
> BPF let me to the conclusion that its raw tracepoint functionality
> requires full events.  I didn't see any other way to do it.

I did have a patch that allowed that. It might be worth trying to upstream it.
It just required a new macro which could be problematic.

https://github.com/qais-yousef/linux/commit/fb9fea29edb8af327e6b2bf3bc41469a8e66df8b

With the above I could attach using bpf::RAW_TRACEPOINT mechanism.

Cheers

--
Qais Yousef