From mboxrd@z Thu Jan 1 00:00:00 1970 From: "Michael S. Tsirkin" Subject: Re: [PATCH net-next 7/8] vhost_net: try batch dequing from skb array Date: Thu, 30 Mar 2017 00:47:33 +0300 Message-ID: <20170330004654-mutt-send-email-mst@kernel.org> References: <1490069087-4783-1-git-send-email-jasowang@redhat.com> <1490069087-4783-8-git-send-email-jasowang@redhat.com> <20170322155111-mutt-send-email-mst@kernel.org> <674632255.8752546.1490784387956.JavaMail.zimbra@redhat.com> Mime-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: base64 Return-path: Content-Disposition: inline In-Reply-To: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: virtualization-bounces@lists.linux-foundation.org Errors-To: virtualization-bounces@lists.linux-foundation.org To: Jason Wang Cc: Pankaj Gupta , netdev@vger.kernel.org, linux-kernel@vger.kernel.org, kvm@vger.kernel.org, virtualization@lists.linux-foundation.org List-Id: virtualization@lists.linuxfoundation.org T24gV2VkLCBNYXIgMjksIDIwMTcgYXQgMDY6NTM6MjdQTSArMDgwMCwgSmFzb24gV2FuZyB3cm90 ZToKPiAKPiAKPiBPbiAyMDE35bm0MDPmnIgyOeaXpSAxODo0NiwgUGFua2FqIEd1cHRhIHdyb3Rl Ogo+ID4gSGkgSmFzb24sCj4gPiAKPiA+ID4gT24gMjAxN+W5tDAz5pyIMjPml6UgMTM6MzQsIEph c29uIFdhbmcgd3JvdGU6Cj4gPiA+ID4gCj4gPiA+ID4gPiA+ICt7Cj4gPiA+ID4gPiA+ICsgICAg aWYgKHJ2cS0+cmggIT0gcnZxLT5ydCkKPiA+ID4gPiA+ID4gKyAgICAgICAgZ290byBvdXQ7Cj4g PiA+ID4gPiA+ICsKPiA+ID4gPiA+ID4gKyAgICBydnEtPnJoID0gcnZxLT5ydCA9IDA7Cj4gPiA+ ID4gPiA+ICsgICAgcnZxLT5ydCA9IHNrYl9hcnJheV9jb25zdW1lX2JhdGNoZWRfYmgocnZxLT5y eF9hcnJheSwgcnZxLT5yeHEsCj4gPiA+ID4gPiA+ICsgICAgICAgICAgICAgICAgICAgICAgICBW SE9TVF9SWF9CQVRDSCk7Cj4gPiA+ID4gPiBBIGNvbW1lbnQgZXhwbGFpbmluZyB3aHkgaXMgaXMg LWJoIHdvdWxkIGJlIGhlbHBmdWwuCj4gPiA+ID4gT2suCj4gPiA+ID4gCj4gPiA+ID4gVGhhbmtz Cj4gPiA+IFJldGhpbmsgYWJvdXQgdGhpcy4gSXQgbG9va3MgbGlrZSAtYmggaXMgbm90IG5lZWRl ZCBpbiB0aGlzIGNhc2Ugc2luY2UKPiA+ID4gbm8gY29uc3VtZXIgcnVuIGluIGJoLgo+ID4gSW4g dGhhdCBjYXNlIGRvIHdlIG5lZWQgb3RoZXIgdmFyaWFudHMgb2YgInB0cl9yaW5nX2NvbnN1bWVf YmF0Y2hlZF8qKCkiIGZ1bmN0aW9ucy4KPiA+IEFyZSB3ZSBwbGFubmluZyB0byB1c2UgdGhlbSBp biBmdXR1cmU/Cj4gCj4gSSB0aGluayB3ZSdkIGJldHRlciBrZWVwIHRoZW0sIHNpbmNlIGl0IHNl cnZlcyBhcyBoZWxwZXJzLiBZb3UgY2FuIHNlZSB0aGF0Cj4gbm90IGFsbCB0aGUgaGVscGVycyBp biBwdHJfcmluZyBoYXMgcmVhbCB1c2VycywgYnV0IHRoZXkgd2VyZSBwcmVwYXJlZCBmb3IKPiB0 aGUgZnV0dXJlIHVzZS4KPiAKPiBUaGFua3MKCk1ha2VzIHNlbnNlIGZvciBiYXNpYyBidWlsZGlu ZyBibG9ja3MgYnV0IEknbSBub3Qgc3VyZSB3ZQpuZWVkIHRvIGRvIGl0IGZvciBhbGwgQVBJcy4K Cgo+ID4gCj4gPiA+IFRoYW5rcwo+ID4gPiAKX19fX19fX19fX19fX19fX19fX19fX19fX19fX19f X19fX19fX19fX19fX19fX18KVmlydHVhbGl6YXRpb24gbWFpbGluZyBsaXN0ClZpcnR1YWxpemF0 aW9uQGxpc3RzLmxpbnV4LWZvdW5kYXRpb24ub3JnCmh0dHBzOi8vbGlzdHMubGludXhmb3VuZGF0 aW9uLm9yZy9tYWlsbWFuL2xpc3RpbmZvL3ZpcnR1YWxpemF0aW9u From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932852AbdC2Vrv (ORCPT ); Wed, 29 Mar 2017 17:47:51 -0400 Received: from mx1.redhat.com ([209.132.183.28]:35996 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932201AbdC2Vrf (ORCPT ); Wed, 29 Mar 2017 17:47:35 -0400 DMARC-Filter: OpenDMARC Filter v1.3.2 mx1.redhat.com A7F1D8047D Authentication-Results: ext-mx04.extmail.prod.ext.phx2.redhat.com; dmarc=none (p=none dis=none) header.from=redhat.com Authentication-Results: ext-mx04.extmail.prod.ext.phx2.redhat.com; spf=pass smtp.mailfrom=mst@redhat.com DKIM-Filter: OpenDKIM Filter v2.11.0 mx1.redhat.com A7F1D8047D Date: Thu, 30 Mar 2017 00:47:33 +0300 From: "Michael S. Tsirkin" To: Jason Wang Cc: Pankaj Gupta , kvm@vger.kernel.org, virtualization@lists.linux-foundation.org, netdev@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH net-next 7/8] vhost_net: try batch dequing from skb array Message-ID: <20170330004654-mutt-send-email-mst@kernel.org> References: <1490069087-4783-1-git-send-email-jasowang@redhat.com> <1490069087-4783-8-git-send-email-jasowang@redhat.com> <20170322155111-mutt-send-email-mst@kernel.org> <674632255.8752546.1490784387956.JavaMail.zimbra@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.28]); Wed, 29 Mar 2017 21:47:34 +0000 (UTC) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, Mar 29, 2017 at 06:53:27PM +0800, Jason Wang wrote: > > > On 2017年03月29日 18:46, Pankaj Gupta wrote: > > Hi Jason, > > > > > On 2017年03月23日 13:34, Jason Wang wrote: > > > > > > > > > > +{ > > > > > > + if (rvq->rh != rvq->rt) > > > > > > + goto out; > > > > > > + > > > > > > + rvq->rh = rvq->rt = 0; > > > > > > + rvq->rt = skb_array_consume_batched_bh(rvq->rx_array, rvq->rxq, > > > > > > + VHOST_RX_BATCH); > > > > > A comment explaining why is is -bh would be helpful. > > > > Ok. > > > > > > > > Thanks > > > Rethink about this. It looks like -bh is not needed in this case since > > > no consumer run in bh. > > In that case do we need other variants of "ptr_ring_consume_batched_*()" functions. > > Are we planning to use them in future? > > I think we'd better keep them, since it serves as helpers. You can see that > not all the helpers in ptr_ring has real users, but they were prepared for > the future use. > > Thanks Makes sense for basic building blocks but I'm not sure we need to do it for all APIs. > > > > > Thanks > > >