linux-kernel - Re: [RFC][PATCH 08/10] sched/fair: Implement delayed dequeue

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

Message-ID: <b344235ed5e2af6c573ff371d3687f0fa7bc5c5e.camel@gmx.de>
Date: Sun, 28 Apr 2024 18:32:49 +0200
From: Mike Galbraith <efault@....de>
To: Peter Zijlstra <peterz@...radead.org>
Cc: K Prateek Nayak <kprateek.nayak@....com>, mingo@...hat.com, 
 juri.lelli@...hat.com, vincent.guittot@...aro.org,
 dietmar.eggemann@....com,  rostedt@...dmis.org, bsegall@...gle.com,
 mgorman@...e.de, bristot@...hat.com,  vschneid@...hat.com,
 linux-kernel@...r.kernel.org, wuyun.abel@...edance.com, 
 tglx@...utronix.de, Chen Yu <yu.c.chen@...el.com>, Oliver Sang
 <oliver.sang@...el.com>
Subject: Re: [RFC][PATCH 08/10] sched/fair: Implement delayed dequeue

On Sat, 2024-04-27 at 08:42 +0200, Mike Galbraith wrote:
> On Fri, 2024-04-26 at 18:03 +0200, Mike Galbraith wrote:
> > fwiw, tbench liked the previous version better.
>
> The culprit lies somewhere in the new PREEMPT_SHORT patch.

<squint>

Ah, moving the curr eligibility check into pick_curr() left an
ineligible curr to be seen/used further down in pick_eevdf().

found:
        if (!best || (curr && entity_before(curr, best)))
                best = curr;

Nit: PREEMPT_SHORT depending on RUN_TO_PARITY looks odd.

	-Mike