From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751635AbdGZL4S (ORCPT ); Wed, 26 Jul 2017 07:56:18 -0400 Received: from mx1.redhat.com ([209.132.183.28]:32437 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751031AbdGZL4R (ORCPT ); Wed, 26 Jul 2017 07:56:17 -0400 DMARC-Filter: OpenDMARC Filter v1.3.2 mx1.redhat.com 2F9D87DCC4 Authentication-Results: ext-mx03.extmail.prod.ext.phx2.redhat.com; dmarc=none (p=none dis=none) header.from=redhat.com Authentication-Results: ext-mx03.extmail.prod.ext.phx2.redhat.com; spf=pass smtp.mailfrom=jasowang@redhat.com Subject: Re: [PATCH net] Revert "vhost: cache used event for better performance" To: Christian Borntraeger , mst@redhat.com Cc: virtualization@lists.linux-foundation.org, kvm@vger.kernel.org, netdev@vger.kernel.org, linux-kernel@vger.kernel.org References: <1501056197-3368-1-git-send-email-jasowang@redhat.com> From: Jason Wang Message-ID: Date: Wed, 26 Jul 2017 19:56:09 +0800 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:52.0) Gecko/20100101 Thunderbird/52.2.1 MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: 8bit Content-Language: en-US X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.27]); Wed, 26 Jul 2017 11:56:17 +0000 (UTC) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 2017年07月26日 18:53, Christian Borntraeger wrote: > On 07/26/2017 10:03 AM, Jason Wang wrote: >> This reverts commit 809ecb9bca6a9424ccd392d67e368160f8b76c92. Since it >> was reported to break vhost_net. We want to cache used event and use >> it to check for notification. We try to valid cached used event by >> checking whether or not it was ahead of new, but this is not correct >> all the time, it could be stale and there's no way to know about this. >> >> Signed-off-by: Jason Wang > This would then qualify for stable ? > Yes it is. Thanks