[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]
Message-ID: <ZSPayGSz6HQBp+3W@gmail.com>
Date: Mon, 9 Oct 2023 12:49:44 +0200
From: Ingo Molnar <mingo@...nel.org>
To: yang.yang29@....com.cn
Cc: surenb@...gle.com, peterz@...radead.org, hannes@...xchg.org,
mingo@...hat.com, linux-kernel@...r.kernel.org,
juri.lelli@...hat.com
Subject: Re: [PATCH linux-next v2] sched/psi: Avoid update triggers and
rtpoll_total when it is unnecessary
* yang.yang29@....com.cn <yang.yang29@....com.cn> wrote:
> From: Yang Yang <yang.yang29@....com.cn>
>
> When psimon wakes up and there are no state changes for rtpoll_states,
> it's unnecessary to update triggers and rtpoll_total because the pressures
> being monitored by user have not changed. This will help to slightly reduce
> unnecessary computations of psi.
>
> There are also some minor related optimizations, please see below.
>
> The parameter update_total in update_triggers() is useless now. Since if
> changed_states & group->rtpoll_states is true, new_stall in update_triggers()
> will be true, then update_total should also be true. We have no need for
> update_total to help judgment whether to update rtpoll_total, so delete
> update_total.
>
> Update_triggers() always return now + group->rtpoll_min_period, and the
> return value is only used by psi_rtpoll_work(), so change update_triggers()
> to a void function, let group->rtpoll_next_update = now +
> group->rtpoll_min_period directly.
Yeah, so please split this up into 3 patches: one change per patch, even
if each patch is relatively small.
Thanks,
Ingo
Powered by blists - more mailing lists