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References: <20180206203048.11096-1-rkagan@virtuozzo.com>
	<20180206203048.11096-26-rkagan@virtuozzo.com>
From: Paolo Bonzini <pbonzini@redhat.com>
Message-ID: <61ab4454-9aa3-7291-8b54-bcaee1f74bf0@redhat.com>
Date: Wed, 7 Feb 2018 12:11:50 +0100
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Subject: Re: [Qemu-devel] [RFC PATCH 25/34] scsi: add Hyper-V/VMBus SCSI
 controller
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To: 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>, "Denis V. Lunev" <den@openvz.org>, si-wei liu <si-wei.liu@oracle.com>, Vitaly Kuznetsov <vkuznets@redhat.com>, Cathy Avery <cavery@redhat.com>

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