From: Paolo Bonzini <pbonzini@redhat.com>
To: Dario Faggioli <dfaggioli@suse.com>,
Wanpeng Li <kernellwp@gmail.com>,
linux-kernel@vger.kernel.org, kvm@vger.kernel.org
Cc: "Radim Krčmář" <rkrcmar@redhat.com>,
"Peter Zijlstra" <peterz@infradead.org>,
"Thomas Gleixner" <tglx@linutronix.de>
Subject: Re: [PATCH] KVM: Disable wake-affine vCPU process to mitigate lock holder preemption
Date: Fri, 2 Aug 2019 10:38:53 +0200 [thread overview]
Message-ID: <36f54918-171d-cf72-818e-dc8cec7cd3b0@redhat.com> (raw)
In-Reply-To: <04700afaf68114b5ab329f5a5182e21578c15795.camel@suse.com>
On 01/08/19 14:57, Dario Faggioli wrote:
> Can't we achieve this by removing SD_WAKE_AFFINE from the relevant
> scheduling domains? By acting on
> /proc/sys/kernel/sched_domain/cpuX/domainY/flags, I mean?
>
> Of course this will impact all tasks, not only KVM vcpus. But if the
> host does KVM only anyway...
Perhaps add flags to the unified cgroups hierarchy instead. But if the
"min_cap close to max_cap" heuristics are wrong they should indeed be fixed.
Paolo
prev parent reply other threads:[~2019-08-02 8:38 UTC|newest]
Thread overview: 8+ messages / expand[flat|nested] mbox.gz Atom feed top
2019-07-30 9:33 [PATCH] KVM: Disable wake-affine vCPU process to mitigate lock holder preemption Wanpeng Li
2019-07-30 11:46 ` Paolo Bonzini
2019-08-01 12:39 ` Dario Faggioli
2019-07-30 12:09 ` Peter Zijlstra
2019-08-01 12:57 ` Dario Faggioli
2019-08-02 0:51 ` Wanpeng Li
2019-08-02 8:30 ` Christophe de Dinechin
2019-08-02 8:38 ` Paolo Bonzini [this message]
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