From mboxrd@z Thu Jan  1 00:00:00 1970
From: Marc Zyngier <marc.zyngier@arm.com>
Subject: Re: [RFC PATCH] arm64: KVM: remove fpsimd save/restore from the world
 switch
Date: Fri, 10 Apr 2015 11:08:38 +0100
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To: Peter Maydell <peter.maydell@linaro.org>
Cc: Paolo Bonzini <pbonzini@redhat.com>, "kvm@vger.kernel.org" <kvm@vger.kernel.org>, "linux-arm-kernel@lists.infradead.org" <linux-arm-kernel@lists.infradead.org>, "kvmarm@lists.cs.columbia.edu" <kvmarm@lists.cs.columbia.edu>
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On 10/04/15 11:01, Peter Maydell wrote:
> On 10 April 2015 at 10:11, Marc Zyngier <marc.zyngier@arm.com> wrote:
>> I did some experimentations on arm64 a long while ago (see the
>> kvm-arm64/lazy-fp branch in my tree), and it wasn't that great,
>> apparently because aarch64 userspace tends to be much more FP happy than
>> aarch32, but I'm not completely sure about it.
> 
> Was that with the buggy version of the toolchain that had
> incorrect costs and so was much more inclined to spill
> integer values into the FPU than it should have been?
> It might be worth retesting with a freshly compiled
> userspace some day...

It definitely was with a very old toolchain and an even older userspace.
I'll respin the branch when I get some thime.

Thanks,

	M.
-- 
Jazz is not dead. It just smells funny...