From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751889AbdG2VQQ (ORCPT ); Sat, 29 Jul 2017 17:16:16 -0400 Received: from shards.monkeyblade.net ([184.105.139.130]:42018 "EHLO shards.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751530AbdG2VQO (ORCPT ); Sat, 29 Jul 2017 17:16:14 -0400 Date: Sat, 29 Jul 2017 14:16:13 -0700 (PDT) Message-Id: <20170729.141613.128128727353289484.davem@davemloft.net> To: jasowang@redhat.com Cc: mst@redhat.com, kvm@vger.kernel.org, virtualization@lists.linux-foundation.org, netdev@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH V2 net] Revert "vhost: cache used event for better performance" From: David Miller In-Reply-To: <1501125725-24529-1-git-send-email-jasowang@redhat.com> References: <1501125725-24529-1-git-send-email-jasowang@redhat.com> X-Mailer: Mew version 6.7 on Emacs 25.2 / Mule 6.0 (HANACHIRUSATO) Mime-Version: 1.0 Content-Type: Text/Plain; charset=us-ascii Content-Transfer-Encoding: 7bit X-Greylist: Sender succeeded SMTP AUTH, not delayed by milter-greylist-4.5.12 (shards.monkeyblade.net [149.20.54.216]); Sat, 29 Jul 2017 14:16:14 -0700 (PDT) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Jason Wang Date: Thu, 27 Jul 2017 11:22:05 +0800 > 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. The assumption was that guest won't move > the event idx back, but this could happen in fact when 16 bit index > wraps around after 64K entries. > > Signed-off-by: Jason Wang Applied, thanks.