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Message-ID: <1403646374.4587.178.camel@pasglop>
Subject: Re: [PATCH] vfio: Fix endianness handling for emulated BARs
From: Benjamin Herrenschmidt <benh@kernel.crashing.org>
To: Alexander Graf <agraf@suse.de>
Cc: Alexey Kardashevskiy <aik@ozlabs.ru>,
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Date: Wed, 25 Jun 2014 07:46:14 +1000
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On Tue, 2014-06-24 at 12:41 +0200, Alexander Graf wrote:
> Is there actually any difference in generated code with this patch 
> applied and without? I would hope that iowrite..() is inlined and 
> cancels out the cpu_to_le..() calls that are also inlined?

No, the former uses byteswapping asm, the compiler can't "cancel" it
out, but the overhead of the additional byteswap might not be
measurable.

Cheers,
Ben.