From mboxrd@z Thu Jan  1 00:00:00 1970
From: Avi Kivity <avi@redhat.com>
Subject: Re: KVM: guest: only batch user pte updates
Date: Wed, 11 Feb 2009 13:56:04 +0200
Message-ID: <4992BCD4.7040505@redhat.com>
References: <20090210214532.GA4082@amt.cnet> <4991FD0D.1070108@goop.org> <20090210224141.GA4471@amt.cnet> <49920A68.5030408@goop.org>
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Cc: Marcelo Tosatti <mtosatti@redhat.com>,
	kvm-devel <kvm@vger.kernel.org>,
	Rusty Russell <rusty@rustcorp.com.au>,
	Zachary Amsden <zach@vmware.com>
To: Jeremy Fitzhardinge <jeremy@goop.org>
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Jeremy Fitzhardinge wrote:
>>
>> Yes. It seems however that only set_pte_at/pte_update/_defer are
>> used under significatly long lazy mmu sections (long as in number of
>> updates). Is it worthwhile to bother (and risk) batching kernel pte 
>> updates ?
>>   
>
> Well, that depends on how expensive each update is.  For something 
> like kunmap atomic, I think combining the clear+tlb flush probably is 
> worthwhile.

I agree, kmap_atomic() is fairly common.

-- 
error compiling committee.c: too many arguments to function