From mboxrd@z Thu Jan  1 00:00:00 1970
From: Andi Kleen <andi@firstfloor.org>
Subject: Re: [RFC PATCH 3/3] KVM: MMU: Optimize guest page table walk
Date: Thu, 28 Apr 2011 19:46:00 -0700
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Cc: Takuya Yoshikawa <takuya.yoshikawa@gmail.com>, mtosatti@redhat.com,
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To: Avi Kivity <avi@redhat.com>
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Avi Kivity <avi@redhat.com> writes:
>
> Good optimization.  copy_from_user() really isn't optimized for short
> buffers, I expect much of the improvement comes from that.

Actually it is equivalent to get_user for the lenghts supported by
get_user, assuming you pass in a constant length. You probably do not.

-Andi

-- 
ak@linux.intel.com -- Speaking for myself only