From mboxrd@z Thu Jan  1 00:00:00 1970
From: Bart Van Assche <bvanassche@acm.org>
Subject: Re: [PATCH 1/2] vhost: Reduce vhost_work_flush() wakeup latency
Date: Wed, 14 Aug 2013 17:22:36 +0200
Message-ID: <520BA0BC.6080202@acm.org>
References: <520B2B47.9040002@acm.org> <520B2B88.6020307@acm.org> <20130814113739.GE5430@redhat.com>
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Cc: Asias He <asias@redhat.com>, kvm-devel <kvm@vger.kernel.org>
To: "Michael S. Tsirkin" <mst@redhat.com>
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On 08/14/13 13:37, Michael S. Tsirkin wrote:
> On Wed, Aug 14, 2013 at 09:02:32AM +0200, Bart Van Assche wrote:
>> If the TIF_NEED_RESCHED task flag is set, wake up any vhost_work_flush()
>> waiters before rescheduling instead of after rescheduling.
>>
>> Signed-off-by: Bart Van Assche <bvanassche@acm.org>
>> Cc: Michael S. Tsirkin <mst@redhat.com>
>> Cc: Asias He <asias@redhat.com>
>
> Why exactly? It's not like flush needs to be extra fast ...

I'm not worried about how fast a flush is processed either. But I think 
this patch is a nice cleanup of the vhost_worker() function. It 
eliminates the uninitialized_var() construct and moves the assignment of 
"done_seq" below the read of "queue_seq".

Bart.