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Subject: Re: [PATCH 6/6] KVM: perform a wake_up in kvm_make_all_cpus_request
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References: <20170406202056.18379-1-rkrcmar@redhat.com>
 <20170406202056.18379-7-rkrcmar@redhat.com>
Cc: Christoffer Dall <cdall@linaro.org>, Andrew Jones <drjones@redhat.com>,
        Marc Zyngier <marc.zyngier@arm.com>,
        Christian Borntraeger <borntraeger@de.ibm.com>,
        Cornelia Huck <cornelia.huck@de.ibm.com>,
        James Hogan <james.hogan@imgtec.com>,
        Paul Mackerras <paulus@ozlabs.org>
From: Paolo Bonzini <pbonzini@redhat.com>
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Date: Tue, 11 Apr 2017 13:37:54 +0800
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On 07/04/2017 04:20, Radim Krčmář wrote:
> I think that most requests do not need the wake up, so we would flip the
> bit then.

True.  I may need a bit more convincing, but let's see the patches:

- point against: on the other hand no wakeup is a bug, possibly hard to
find, while an extra wakeup is just annoying.

- point in favor: the same argument (multiplied by 9000) would apply to
a wait flag in the request number, but it would be obviously stupid to
add a no_wait flag to all requests except the couple that need it.

Thanks,

Paolo