From: Tejun Heo <tj@kernel.org>
To: Andrea Righi <arighi@nvidia.com>
Cc: David Vernet <void@manifault.com>,
linux-kernel@vger.kernel.org, kernel-team@meta.com,
sched-ext@meta.com, Changwoo Min <multics69@gmail.com>
Subject: Re: [PATCH sched_ext/for-6.13 1/2] sched_ext: Avoid live-locking bypass mode switching
Date: Tue, 5 Nov 2024 14:26:38 -1000 [thread overview]
Message-ID: <Zyq3vmLP4R2WjnmB@slm.duckdns.org> (raw)
In-Reply-To: <Zyqw9rI-hbxhMqv_@gpd3>
Hello,
On Wed, Nov 06, 2024 at 12:57:42AM +0100, Andrea Righi wrote:
...
> Do you think there's any benefit using the idle injection framework here
> instead of this cpu_relax() loop? At the end we're trying to throttle
> the scx scheduler from hammering a DSQ until the scheduler is kicked
> out, so we may just inject real idle cycles?
That involves switching to the dedicated task and so on, right? When this is
needed, we can't even trust whether the system is going to make forward
progress within the scheduler. I don't think it'd be a good idea to call out
to something more complicated. Also, from forward-progress-guaranteeing
point of view, cpu_relax() is as good as anything else and this shouldn't be
active long enough for power consumption to be a factor.
Thanks.
--
tejun
next prev parent reply other threads:[~2024-11-06 0:26 UTC|newest]
Thread overview: 14+ messages / expand[flat|nested] mbox.gz Atom feed top
2024-11-05 21:48 [PATCH sched_ext/for-6.13 1/2] sched_ext: Avoid live-locking bypass mode switching Tejun Heo
2024-11-05 21:49 ` [PATCH sched_ext/for-6.13 2/2] sched_ext: Enable the ops breather and eject BPF scheduler on softlockup Tejun Heo
2024-11-06 21:32 ` Doug Anderson
2024-11-06 22:08 ` Tejun Heo
2024-11-06 23:02 ` Doug Anderson
2024-11-06 23:07 ` Tejun Heo
2024-11-06 23:20 ` Doug Anderson
2024-11-07 19:31 ` Tejun Heo
2024-11-08 20:38 ` Tejun Heo
2024-11-05 22:03 ` [PATCH sched_ext/for-6.13 1/2] sched_ext: Avoid live-locking bypass mode switching David Vernet
2024-11-05 23:02 ` Tejun Heo
2024-11-05 23:57 ` Andrea Righi
2024-11-06 0:26 ` Tejun Heo [this message]
2024-11-06 0:33 ` Andrea Righi
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