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Date:   Mon, 31 Jul 2023 20:06:01 +0200
From:   Peter Zijlstra <peterz@infradead.org>
To:     "Rafael J. Wysocki" <rafael@kernel.org>
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Subject: Re: [RFC][PATCH 1/3] cpuidle: Inject tick boundary state
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On Mon, Jul 31, 2023 at 07:27:27PM +0200, Rafael J. Wysocki wrote:

> BTW, note that teo records timers as "hits", because it has an idea
> about when the next timer should occur and that's because it calls
> tick_nohz_get_sleep_length().
> 
> If it doesn't call that function, it will not be able to tell the
> difference between a non-tick timer and any other wakeup, so the
> non-tick timer wakeups will then be recorded as "intercepts" which
> will skew it towards shallow states over time.  That's one of the
> reasons why I would prefer to only avoid calling
> tick_nohz_get_sleep_length() when the candidate idle state is really
> shallow.

Can be fixed using tick_nohz_get_next_hrtimer() I think. Let me try that
tomorrow.