From: Ingo Molnar <mingo@kernel.org>
To: yang.yang29@zte.com.cn
Cc: surenb@google.com, peterz@infradead.org, hannes@cmpxchg.org,
mingo@redhat.com, linux-kernel@vger.kernel.org,
juri.lelli@redhat.com
Subject: Re: [PATCH linux-next 2/3] sched/psi: Avoid update triggers and rtpoll_total when it is unnecessary
Date: Mon, 9 Oct 2023 14:52:02 +0200 [thread overview]
Message-ID: <ZSP3cuEsgwWcIKRw@gmail.com> (raw)
In-Reply-To: <202310092030430136422@zte.com.cn>
* yang.yang29@zte.com.cn <yang.yang29@zte.com.cn> wrote:
> From: Yang Yang <yang.yang29@zte.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 had not changed. This will help to slightly reduce
> unnecessary computations of psi.
>
> And update group->rtpoll_next_update after called update_triggers() and
> update rtpoll_total. This will prevent bugs if update_triggers() uses
> group->rtpoll_next_update in the future, and it makes more sense
> to set the next update time after we finished the current update.
> if (now >= group->rtpoll_next_update) {
> - update_triggers(group, now, &update_total, PSI_POLL);
> - group->rtpoll_next_update = now + group->rtpoll_min_period;
> - if (update_total)
> + if (changed_states & group->rtpoll_states) {
> + update_triggers(group, now, &update_total, PSI_POLL);
> memcpy(group->rtpoll_total, group->total[PSI_POLL],
> sizeof(group->rtpoll_total));
> + }
> + group->rtpoll_next_update = now + group->rtpoll_min_period;
So please also split out the second change into a separate patch as well,
as it's an unrelated patch to the state-change optimization.
We have a "one conceptual change per patch" rule for most things.
Thanks,
Ingo
next prev parent reply other threads:[~2023-10-09 12:52 UTC|newest]
Thread overview: 38+ messages / expand[flat|nested] mbox.gz Atom feed top
2023-09-13 12:44 [PATCH linux-next] sched/psi: Avoid update triggers and rtpoll_total when it is unnecessary yang.yang29
2023-09-13 23:01 ` Suren Baghdasaryan
2023-09-14 2:02 ` yang.yang29
2023-09-14 5:53 ` yang.yang29
2023-09-14 9:10 ` yang.yang29
2023-09-27 0:14 ` Suren Baghdasaryan
2023-09-27 1:56 ` yang.yang29
2023-09-30 22:32 ` Suren Baghdasaryan
2023-10-07 6:21 ` [PATCH linux-next v2] " yang.yang29
2023-10-09 10:49 ` Ingo Molnar
2023-10-09 12:19 ` [PATCH linux-next 0/3] sched/psi: Optimize the process of updating triggers and rtpoll_total yang.yang29
2023-10-09 12:24 ` [PATCH linux-next 1/3] sched/psi: Change update_triggers() to a void function yang.yang29
2023-10-09 12:48 ` Ingo Molnar
2023-10-09 12:59 ` [tip: sched/core] sched/psi: Change update_triggers() to a 'void' function tip-bot2 for Yang Yang
2023-10-09 12:30 ` [PATCH linux-next 2/3] sched/psi: Avoid update triggers and rtpoll_total when it is unnecessary yang.yang29
2023-10-09 12:52 ` Ingo Molnar [this message]
2023-10-09 17:42 ` Suren Baghdasaryan
2023-10-10 2:12 ` yang.yang29
2023-10-10 3:05 ` [PATCH linux-next v2 0/4] sched/psi: Optimize the process of updating triggers and rtpoll_total yang.yang29
2023-10-10 3:09 ` [PATCH linux-next v2 1/4] sched/psi: Change update_triggers() to a 'void' function yang.yang29
2023-10-10 7:38 ` Ingo Molnar
2023-10-10 8:31 ` [PATCH linux-next v3 0/4] sched/psi: Optimize the process of updating triggers and rtpoll_total yang.yang29
2023-10-10 8:36 ` [PATCH linux-next v3 1/4] sched/psi: Change update_triggers() to a 'void' function yang.yang29
2023-10-19 16:01 ` Suren Baghdasaryan
2023-10-10 8:41 ` [PATCH linux-next v3 2/4] sched/psi: Avoid update triggers and rtpoll_total when it is unnecessary yang.yang29
2023-10-11 21:15 ` Ingo Molnar
2023-10-12 2:13 ` yang.yang29
2023-10-19 16:04 ` Suren Baghdasaryan
2023-10-11 21:20 ` [tip: sched/core] sched/psi: Avoid updating PSI triggers and ->rtpoll_total when there are no state changes tip-bot2 for Yang Yang
2023-10-10 8:42 ` [PATCH linux-next v3 3/4] sched/psi: update rtpoll_next_update after update triggers and rtpoll_total yang.yang29
2023-10-19 16:07 ` Suren Baghdasaryan
2023-10-10 8:45 ` [PATCH linux-next v3 4/4] sched/psi: Delete the function parameter update_total of update_triggers() yang.yang29
2023-10-11 21:20 ` [tip: sched/core] sched/psi: Delete the 'update_total' function parameter from update_triggers() tip-bot2 for Yang Yang
2023-10-19 16:09 ` [PATCH linux-next v3 4/4] sched/psi: Delete the function parameter update_total of update_triggers() Suren Baghdasaryan
2023-10-10 3:20 ` [PATCH linux-next v2 2/4] sched/psi: Avoid update triggers and rtpoll_total when it is unnecessary yang.yang29
2023-10-10 3:24 ` [PATCH linux-next v2 3/4] sched/psi: update rtpoll_next_update after update triggers and rtpoll_total yang.yang29
2023-10-10 3:28 ` [PATCH linux-next v2 4/4] sched/psi: Delete the function parameter update_total of update_triggers() yang.yang29
2023-10-09 12:37 ` [PATCH linux-next 3/3] " yang.yang29
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