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References: <20180206203048.11096-1-rkagan@virtuozzo.com>
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	<61ab4454-9aa3-7291-8b54-bcaee1f74bf0@redhat.com>
From: "Denis V. Lunev" <den@openvz.org>
Message-ID: <901f124d-b256-158e-4870-2bac25fbce71@openvz.org>
Date: Wed, 7 Feb 2018 14:25:05 +0300
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Subject: Re: [Qemu-devel] [RFC PATCH 25/34] scsi: add Hyper-V/VMBus SCSI
 controller
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To: Paolo Bonzini <pbonzini@redhat.com>, Roman Kagan <rkagan@virtuozzo.com>, qemu-devel@nongnu.org
Cc: Ben Warren <ben@skyportsystems.com>, Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>, Krish Sadhukhan <krish.sadhukhan@oracle.com>, "Marcos E. Matsunaga" <Marcos.Matsunaga@oracle.com>, Jan Dakinevich <jan.dakinevich@virtuozzo.com>, Vadim Rozenfeld <vrozenfe@redhat.com>, si-wei liu <si-wei.liu@oracle.com>, Vitaly Kuznetsov <vkuznets@redhat.com>, Cathy Avery <cavery@redhat.com>

On 02/07/2018 02:11 PM, Paolo Bonzini wrote:
> On 06/02/2018 21:30, Roman Kagan wrote:
>> +    blk_io_plug(d->conf.blk);
>> +    if (scsi_req_enqueue(sreq)) {
>> +        scsi_req_continue(sreq);
>> +    }
>> +    blk_io_unplug(d->conf.blk);
> Is plug/unplug really useful?
>
> Paolo
good point. here - no. plug/unplug should be moved to upper
layer, where we process all requests. Plug/Unplug should
cover all currently available bits.

Den