From mboxrd@z Thu Jan 1 00:00:00 1970 From: Joerg Roedel Subject: Re: [PATCH] iommu/iova: Separate atomic variables to improve performance Date: Thu, 11 Apr 2019 15:43:12 +0200 Message-ID: <20190411134312.GC4518@8bytes.org> References: <1554280521-18375-1-git-send-email-zhangshaokun@hisilicon.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: Content-Disposition: inline In-Reply-To: <1554280521-18375-1-git-send-email-zhangshaokun@hisilicon.com> Sender: linux-kernel-owner@vger.kernel.org To: Shaokun Zhang Cc: iommu@lists.linux-foundation.org, linux-kernel@vger.kernel.org, Jinyu Qi List-Id: iommu@lists.linux-foundation.org On Wed, Apr 03, 2019 at 04:35:21PM +0800, Shaokun Zhang wrote: > From: Jinyu Qi > > In struct iova_domain, there are three atomic variables, the former two > are about TLB flush counters which use atomic_add operation, anoter is > used to flush timer that use cmpxhg operation. > These variables are in the same cache line, so it will cause some > performance loss under the condition that many cores call queue_iova > function, Let's isolate the two type atomic variables to different > cache line to reduce cache line conflict. > > Cc: Joerg Roedel > Signed-off-by: Jinyu Qi > --- > include/linux/iova.h | 16 ++++++++-------- > 1 file changed, 8 insertions(+), 8 deletions(-) Applied, thanks. From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-5.5 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_PASS,URIBL_BLOCKED,USER_AGENT_MUTT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 30B69C10F13 for ; Thu, 11 Apr 2019 13:44:04 +0000 (UTC) Received: from mail.linuxfoundation.org (mail.linuxfoundation.org [140.211.169.12]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 0675D2133D for ; Thu, 11 Apr 2019 13:44:03 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 0675D2133D Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=8bytes.org Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=iommu-bounces@lists.linux-foundation.org Received: from mail.linux-foundation.org (localhost [127.0.0.1]) by mail.linuxfoundation.org (Postfix) with ESMTP id C644427C9; Thu, 11 Apr 2019 13:44:03 +0000 (UTC) Received: from smtp1.linuxfoundation.org (smtp1.linux-foundation.org [172.17.192.35]) by mail.linuxfoundation.org (Postfix) with ESMTPS id 6228225F0 for ; Thu, 11 Apr 2019 13:43:16 +0000 (UTC) X-Greylist: from auto-whitelisted by SQLgrey-1.7.6 Received: from theia.8bytes.org (8bytes.org [81.169.241.247]) by smtp1.linuxfoundation.org (Postfix) with ESMTPS id BA195F4 for ; Thu, 11 Apr 2019 13:43:15 +0000 (UTC) Received: by theia.8bytes.org (Postfix, from userid 1000) id A327A42D; Thu, 11 Apr 2019 15:43:13 +0200 (CEST) Date: Thu, 11 Apr 2019 15:43:12 +0200 From: Joerg Roedel To: Shaokun Zhang Subject: Re: [PATCH] iommu/iova: Separate atomic variables to improve performance Message-ID: <20190411134312.GC4518@8bytes.org> References: <1554280521-18375-1-git-send-email-zhangshaokun@hisilicon.com> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <1554280521-18375-1-git-send-email-zhangshaokun@hisilicon.com> User-Agent: Mutt/1.10.1 (2018-07-13) Cc: Jinyu Qi , iommu@lists.linux-foundation.org, linux-kernel@vger.kernel.org X-BeenThere: iommu@lists.linux-foundation.org X-Mailman-Version: 2.1.12 Precedence: list List-Id: Development issues for Linux IOMMU support List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: 7bit Sender: iommu-bounces@lists.linux-foundation.org Errors-To: iommu-bounces@lists.linux-foundation.org Message-ID: <20190411134312.MGyhXQA2ToUdOIZmMGEt7hpA8PBcHKQAEoVWUB7Vzgw@z> On Wed, Apr 03, 2019 at 04:35:21PM +0800, Shaokun Zhang wrote: > From: Jinyu Qi > > In struct iova_domain, there are three atomic variables, the former two > are about TLB flush counters which use atomic_add operation, anoter is > used to flush timer that use cmpxhg operation. > These variables are in the same cache line, so it will cause some > performance loss under the condition that many cores call queue_iova > function, Let's isolate the two type atomic variables to different > cache line to reduce cache line conflict. > > Cc: Joerg Roedel > Signed-off-by: Jinyu Qi > --- > include/linux/iova.h | 16 ++++++++-------- > 1 file changed, 8 insertions(+), 8 deletions(-) Applied, thanks. _______________________________________________ iommu mailing list iommu@lists.linux-foundation.org https://lists.linuxfoundation.org/mailman/listinfo/iommu