From mboxrd@z Thu Jan  1 00:00:00 1970
From: Rusty Russell <rusty@rustcorp.com.au>
Subject: Re: [PATCH] virtio-blk: Disable callback in virtblk_done()
Date: Fri, 28 Sep 2012 15:38:56 +0930
Message-ID: <87fw623chz.fsf@rustcorp.com.au>
References: <1348540577-7474-1-git-send-email-asias@redhat.com>
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To: Asias He <asias@redhat.com>
Cc: virtualization@lists.linux-foundation.org, kvm@vger.kernel.org, "Michael S. Tsirkin" <mst@redhat.com>
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Asias He <asias@redhat.com> writes:
>> I forgot about the cool hack which MST put in to defer event updates
>> using disable_cb/enable_cb.
>
> Hmm, are you talking about virtqueue_enable_cb_delayed()?

Just the fact that virtqueue_disable_cb() prevents updates of
used_index, and then we do the update in virtqueue_enable_cb().

Cheers,
Rusty.