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References: <1643093818-19835-1-git-send-email-huangzhaoyang@gmail.com> <YfAL55Xydar/jKrl@cmpxchg.org>
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From:   Suren Baghdasaryan <surenb@google.com>
Date:   Wed, 26 Jan 2022 08:44:10 -0800
Message-ID: <CAJuCfpEGUH0SDwP9EJ-uA52R7j3pcVXa+gJX3=QtEhJQ5ig6KA@mail.gmail.com>
Subject: Re: [PATCHv4] psi: fix possible trigger missing in the window
To:     Johannes Weiner <hannes@cmpxchg.org>
Cc:     Huangzhaoyang <huangzhaoyang@gmail.com>,
        Peter Zijlstra <peterz@infradead.org>,
        Zhaoyang Huang <zhaoyang.huang@unisoc.com>,
        Ingo Molnar <mingo@redhat.com>, linux-mm <linux-mm@kvack.org>,
        LKML <linux-kernel@vger.kernel.org>
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On Tue, Jan 25, 2022 at 6:40 AM Johannes Weiner <hannes@cmpxchg.org> wrote:
>
> On Tue, Jan 25, 2022 at 02:56:58PM +0800, Huangzhaoyang wrote:
> > From: Zhaoyang Huang <zhaoyang.huang@unisoc.com>
> >
> > When a new threshold breaching stall happens after a psi event was
> > generated and within the window duration, the new event is not
> > generated because the events are rate-limited to one per window. If
> > after that no new stall is recorded then the event will not be
> > generated even after rate-limiting duration has passed. This is
> > happening because with no new stall, window_update will not be called
> > even though threshold was previously breached. To fix this, record
> > threshold breaching occurrence and generate the event once window
> > duration is passed.
> >
> > Suggested-by: Suren Baghdasaryan <surenb@google.com>
> > Signed-off-by: Zhaoyang Huang <zhaoyang.huang@unisoc.com>
>
> Acked-by: Johannes Weiner <hannes@cmpxchg.org>

Looks good. Thanks!

Acked-by: Suren Baghdasaryan <surenb@google.com>