linux-kernel - Re: [PATCH 0/4] sched/fair: Manage lag and run to parity with different slices

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [day] [month] [year] [list]

Message-ID: <20250617092208.GQ1613376@noisy.programming.kicks-ass.net>
Date: Tue, 17 Jun 2025 11:22:08 +0200
From: Peter Zijlstra <peterz@...radead.org>
To: Vincent Guittot <vincent.guittot@...aro.org>
Cc: mingo@...hat.com, juri.lelli@...hat.com, dietmar.eggemann@....com,
	rostedt@...dmis.org, bsegall@...gle.com, mgorman@...e.de,
	vschneid@...hat.com, linux-kernel@...r.kernel.org
Subject: Re: [PATCH 0/4] sched/fair: Manage lag and run to parity with
 different slices

On Fri, Jun 13, 2025 at 04:05:10PM +0200, Vincent Guittot wrote:
> Vincent Guittot (3):
>   sched/fair: Use protect_slice() instead of direct comparison
>   sched/fair: Limit run to parity to the min slice of enqueued entities
>   sched/fair: Improve NO_RUN_TO_PARITY

Ah. I wrote these here patches and then totally forgot about them :/.
They take a different approach.

The approach I took was to move decision to stick with curr after pick,
instead of before it. That way we can evaluate the tree at the time of
preemption.



View attachment "peterz-sched-fair-fix-delayed-requeue.patch" of type "text/x-diff" (818 bytes)

View attachment "peterz-sched-fair-fix-preempt-short.patch" of type "text/x-diff" (2298 bytes)

View attachment "peterz-sched-fair-fix-preempt-short-2.patch" of type "text/x-diff" (1020 bytes)