From mboxrd@z Thu Jan  1 00:00:00 1970
From: Peter Xu <peterx@redhat.com>
Subject: Re: [PATCH v3 6/6] vfio/quirks: Enable ioeventfd
 quirks to be handled by vfio directly
Date: Fri, 4 May 2018 10:17:34 +0800
Message-ID: <20180504021734.GJ29580@xz-mi>
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Cc: eric.auger@redhat.com, qemu-devel@nongnu.org, kvm@vger.kernel.org
To: Alex Williamson <alex.williamson@redhat.com>
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On Thu, May 03, 2018 at 03:45:13PM -0600, Alex Williamson wrote:
> With vfio ioeventfd support, we can program vfio-pci to perform a
> specified BAR write when an eventfd is triggered.  This allows the
> KVM ioeventfd to be wired directly to vfio-pci, entirely avoiding
> userspace handling for these events.  On the same micro-benchmark
> where the ioeventfd got us to almost 90% of performance versus
> disabling the GeForce quirks, this gets us to within 95%.
> 
> Signed-off-by: Alex Williamson <alex.williamson@redhat.com>

Reviewed-by: Peter Xu <peterx@redhat.com>

-- 
Peter Xu