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Date: Fri, 27 May 2016 08:36:02 +0800
From: Fam Zheng <famz@redhat.com>
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Subject: Re: [Qemu-devel] [PATCH V2] block/io: optimize bdrv_co_pwritev for
 small requests
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To: Paolo Bonzini <pbonzini@redhat.com>
Cc: Peter Lieven <pl@kamp.de>, kwolf@redhat.com, qemu-block@nongnu.org, qemu-devel@nongnu.org, stefanha@redhat.com, mreitz@redhat.com

On Thu, 05/26 11:20, Paolo Bonzini wrote:
> 
> 
> On 26/05/2016 10:30, Fam Zheng wrote:
> >> > 
> >> > This doesn't look too wrong...  Should the right sequence of events be
> >> > head/after_head or head/after_tail?  It's probably simplest to just emit
> >> > all four events.
> > I've no idea. (That's why I leaned towards fixing the test case).
> 
> Well, fixing the testcase means knowing what events should be emitted.
> 
> QEMU with Peter's patch emits head/after_head.  If the right one is
> head/after_tail, _both QEMU and the testcase_ need to be adjusted.  Your
> patch keeps the backwards-compatible route.

Yes, I mean I was not very convinced in tweaking the events at all: each pair
of them has been emitted around bdrv_aligned_preadv(), and the new branch
doesn't do it anymore. So I don't see a reason to add events here.

Fam