From mboxrd@z Thu Jan 1 00:00:00 1970 From: Yuanhan Liu Subject: Re: [PATCH v7] vhost: support virtqueue interrupt/notification suppression Date: Tue, 9 Jan 2018 20:58:58 +0800 Message-ID: <20180109125858.GI29540@yliu-mob> References: <1514310190-140916-1-git-send-email-junjie.j.chen@intel.com> <1515495828-190409-1-git-send-email-junjie.j.chen@intel.com> <2DBBFF226F7CF64BAFCA79B681719D953A3220A3@shsmsx102.ccr.corp.intel.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: "Chen, Junjie J" , "maxime.coquelin@redhat.com" , "Wang, Xiao W" , "Bie, Tiwei" , "dev@dpdk.org" To: "Yao, Lei A" Return-path: Received: from out3-smtp.messagingengine.com (out3-smtp.messagingengine.com [66.111.4.27]) by dpdk.org (Postfix) with ESMTP id ECE1F1B01E for ; Tue, 9 Jan 2018 13:59:05 +0100 (CET) Content-Disposition: inline In-Reply-To: <2DBBFF226F7CF64BAFCA79B681719D953A3220A3@shsmsx102.ccr.corp.intel.com> List-Id: DPDK patches and discussions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: dev-bounces@dpdk.org Sender: "dev" On Tue, Jan 09, 2018 at 07:34:17AM +0000, Yao, Lei A wrote: > > > > -----Original Message----- > > From: Chen, Junjie J > > Sent: Tuesday, January 9, 2018 7:04 PM > > To: yliu@fridaylinux.org; maxime.coquelin@redhat.com; Wang, Xiao W > > ; Bie, Tiwei ; Yao, Lei A > > > > Cc: dev@dpdk.org; Chen, Junjie J > > Subject: [PATCH v7] vhost: support virtqueue interrupt/notification > > suppression > > > > The driver can suppress interrupt when VIRTIO_F_EVENT_IDX feature bit is > > negotiated. The driver set vring flags to 0, and MAY use used_event in > > available ring to advise device interrupt util reach an index specified > > by used_event. The device ignore the lower bit of vring flags, and send > > an interrupt when index reach used_event. > > > > The device can suppress notification in a manner analogous to the ways > > driver suppress interrupt. The device manipulates flags or avail_event in > > the used ring in the same way the driver manipulates flags or used_event in > > available ring. > > > > Signed-off-by: Junjie Chen > Tested-by: Lei Yao Applied to dpdk-next-virtio. Thanks. --yliu > VM2VM Iperf test has been executed with virtio-net driver after apply this patch. > No performance drop. > CPU: Intel(R) Xeon(R) CPU E5-2699 v4 @ 2.20GHz > Host OS: Ubuntu 16.04 > Guest OS: Ubuntu 16.04 > Kernel: 4.4.0