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Subject: Re: [PATCH 8/8] KVM: PPC: Add hugepage support for IOMMU in-kernel
 handling
From: Benjamin Herrenschmidt <benh@kernel.crashing.org>
To: Alexander Graf <agraf@suse.de>
Date: Wed, 10 Jul 2013 20:39:13 +1000
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Cc: kvm@vger.kernel.org, Alexey Kardashevskiy <aik@ozlabs.ru>,
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 Alex Williamson <alex.williamson@redhat.com>,
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On Wed, 2013-07-10 at 12:33 +0200, Alexander Graf wrote:
> 
> It's not exactly obvious that you're calling it with writing == 1 :).
> Can you create a new local variable "is_write" in the calling
> function, set that to 1 before the call to get_user_pages_fast and
> pass it in instead of the 1? The compiler should easily optimize all
> of that away, but it makes the code by far easier to read.

Ugh ?

Nobody else does that .... (look at futex :-)

Ben.