From mboxrd@z Thu Jan  1 00:00:00 1970
From: Christian Borntraeger <borntraeger@de.ibm.com>
Subject: Re: [PATCH 1/3v2] kvm-s390: Implement the directed yield (diag 9c)
 hypervisor call for KVM
Date: Tue, 24 Apr 2012 17:47:34 +0200
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Cc: Marcelo Tossati <mtosatti@redhat.com>,
	Carsten Otte <cotte@de.ibm.com>,
	Alexander Graf <agraf@suse.de>,
	Jens Freimann <jfrei@linux.vnet.ibm.com>,
	Cornelia Huck <cornelia.huck@de.ibm.com>,
	Heiko Carstens <heiko.carstens@de.ibm.com>,
	Martin Schwidefsky <schwidefsky@de.ibm.com>,
	Heinz Graalfs <graalfs@linux.vnet.ibm.com>,
	KVM <kvm@vger.kernel.org>, Konstantin Weitz <WEITZKON@de.ibm.com>
To: Avi Kivity <avi@redhat.com>
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> I think the code will me more readable, and less obvious that is was
> copied from kvm_vcpu_on_spin(), if you put all the processing outside
> the loop, except for matching the vpu itself.
> 
> So the code reads
> 
>    find a vcpu
>    obtain the task
>    do the yield
> 
> instead of looking like you're doing the processing for every vcpu.  The
> loop is just a slow lookup which might some day be replaced by a table
> lookup.

Ok. We might also have a kvm_vcpu_on_spin_directed in common code,
Would you prefer that? 

Christian