From: Fernand Sieber <sieberf@amazon.com>
To: <mingo@redhat.com>, <peterz@infradead.org>
Cc: <linux-kernel@vger.kernel.org>, <juri.lelli@redhat.com>,
<vincent.guittot@linaro.org>, <dietmar.eggemann@arm.com>,
<rostedt@goodmis.org>, <bsegall@google.com>, <mgorman@suse.de>,
<bristot@redhat.com>, <vschneid@redhat.com>, <dwmw@amazon.co.uk>,
<jschoenh@amazon.de>, <liuyuxua@amazon.com>, <graf@amazon.de>
Subject: [PATCH 0/4] sched/fair: Core sched wake up path improvements
Date: Mon, 22 Sep 2025 14:39:21 +0200 [thread overview]
Message-ID: <cover.1758543008.git.sieberf@amazon.com> (raw)
This patch series addresses several issues and improvements in the core
scheduling within the fair scheduler's wake-up paths. The overall result
is better task placement reducing force idle.
The main issues addressed are as follows:
Slow path:
1. Fix incorrect cookie matching logic that wrongly discards idle cores
2. Better fallback logic when no cookie matching target is found
Fast path:
3. Add cookie checks in wake affine idle to prevent force idle
4. Enhance task selection in select idle sibling to consider cookies
Fernand Sieber (4):
sched/fair: Fix cookie check on __select_idle_cpu()
sched/fair: Still look for the idlest cpu with no matching cookie
sched/fair: Add cookie checks on wake idle path
sched/fair: Add more core cookie check in wake up fast path
kernel/sched/fair.c | 49 ++++++++++++++++++++++++++++++++------------
kernel/sched/sched.h | 41 ++++++++++++++++++++----------------
2 files changed, 59 insertions(+), 31 deletions(-)
--
2.43.0
Amazon Development Centre (South Africa) (Proprietary) Limited
29 Gogosoa Street, Observatory, Cape Town, Western Cape, 7925, South Africa
Registration Number: 2004 / 034463 / 07
next reply other threads:[~2025-09-22 12:40 UTC|newest]
Thread overview: 15+ messages / expand[flat|nested] mbox.gz Atom feed top
2025-09-22 12:39 Fernand Sieber [this message]
2025-09-22 12:39 ` [PATCH 1/4] sched/fair: Fix cookie check on __select_idle_cpu() Fernand Sieber
2025-09-23 8:42 ` K Prateek Nayak
2025-09-25 6:35 ` Madadi Vineeth Reddy
2025-09-22 12:39 ` [PATCH 2/4] sched/fair: Still look for the idlest cpu with no matching cookie Fernand Sieber
2025-09-23 1:51 ` K Prateek Nayak
2025-09-23 7:32 ` Fernand Sieber
2025-09-23 7:44 ` Fernand Sieber
2025-09-22 12:39 ` [PATCH 3/4] sched/fair: Add cookie checks on wake idle path Fernand Sieber
2025-09-22 12:39 ` [PATCH 4/4] sched/fair: Add more core cookie check in wake up fast path Fernand Sieber
2025-09-23 8:55 ` K Prateek Nayak
2025-09-23 9:30 ` Fernand Sieber
2025-09-24 4:21 ` K Prateek Nayak
2025-11-05 15:34 ` [PATCH 4/4] sched/fair: Add more core cookie check in wake up Fernand Sieber
2025-11-20 10:30 ` [PATCH 4/4] sched/fair: Add more core cookie check in wake up fast path Fernand Sieber
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