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Subject: Re: [RFC] perf arm-spe: Track task context switch for cpu-mode events
To:     Namhyung Kim <namhyung@kernel.org>
Cc:     Leo Yan <leo.yan@linaro.org>, James Clark <james.clark@arm.com>,
        Arnaldo Carvalho de Melo <acme@kernel.org>,
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From:   German Gomez <german.gomez@arm.com>
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Date:   Mon, 11 Oct 2021 14:58:40 +0100
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Hi Namhyung,

On 09/10/2021 01:12, Namhyung Kim wrote:

> Hi German,
>
> On Fri, Oct 8, 2021 at 4:08 AM German Gomez <german.gomez@arm.com> wrote:
>
> [...]
>
> I think we should use context-switch even for kernel samples, but
> only if the context packets are not available.
>
> Thanks,
> Namhyung

I think I agree with that you say. If --switch-events is not enabled by
default like you mention, an user could opt-in to using the fallback if
there's no better option for kernel tracing yet.

@Leo, what are your thoughts on this? Perhaps adding a warning message
to tell the user to please enable context packets, otherwise the results
will have workload-dependant inaccuracies, could be a good enough
compromise?

Thanks,
German