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=-10.2 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,NICE_REPLY_A, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_SANE_1 autolearn=unavailable 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 77335C64E7A for ; Tue, 1 Dec 2020 15:36:19 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 1A2B42067D for ; Tue, 1 Dec 2020 15:36:19 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2391816AbgLAPgS (ORCPT ); Tue, 1 Dec 2020 10:36:18 -0500 Received: from frasgout.his.huawei.com ([185.176.79.56]:2185 "EHLO frasgout.his.huawei.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2387672AbgLAPgR (ORCPT ); Tue, 1 Dec 2020 10:36:17 -0500 Received: from fraeml702-chm.china.huawei.com (unknown [172.18.147.207]) by frasgout.his.huawei.com (SkyGuard) with ESMTP id 4ClmMz6ZdRz67KjJ; Tue, 1 Dec 2020 23:33:35 +0800 (CST) Received: from lhreml724-chm.china.huawei.com (10.201.108.75) by fraeml702-chm.china.huawei.com (10.206.15.51) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA256_P256) id 15.1.2106.2; Tue, 1 Dec 2020 16:35:29 +0100 Received: from [10.47.7.145] (10.47.7.145) by lhreml724-chm.china.huawei.com (10.201.108.75) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.1913.5; Tue, 1 Dec 2020 15:35:28 +0000 Subject: Re: [RESEND PATCH v3 0/4] iommu/iova: Solve longterm IOVA issue To: , , CC: , , , , References: <1605608734-84416-1-git-send-email-john.garry@huawei.com> From: John Garry Message-ID: Date: Tue, 1 Dec 2020 15:35:02 +0000 User-Agent: Mozilla/5.0 (Windows NT 10.0; WOW64; rv:68.0) Gecko/20100101 Thunderbird/68.1.2 MIME-Version: 1.0 In-Reply-To: <1605608734-84416-1-git-send-email-john.garry@huawei.com> Content-Type: text/plain; charset="utf-8"; format=flowed Content-Language: en-US Content-Transfer-Encoding: 7bit X-Originating-IP: [10.47.7.145] X-ClientProxiedBy: lhreml725-chm.china.huawei.com (10.201.108.76) To lhreml724-chm.china.huawei.com (10.201.108.75) X-CFilter-Loop: Reflected Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 17/11/2020 10:25, John Garry wrote: Hi Will, Is there any chance that we can get these picked up for 5.11? We've seen this issue solved here for a long time. Or, @Robin, let me know if not happy with this since v1. BTW, patch #4 has been on the go for ~1 year now, and is a nice small optimisation from Cong, which I picked up and already had a RB tag. Thanks, John > This series contains a patch to solve the longterm IOVA issue which > leizhen originally tried to address at [0]. > > A sieved kernel log is at the following, showing periodic dumps of IOVA > sizes, per CPU and per depot bin, per IOVA size granule: > https://raw.githubusercontent.com/hisilicon/kernel-dev/topic-iommu-5.10-iova-debug-v3/aging_test > > Notice, for example, the following logs: > [13175.355584] print_iova1 cpu_total=40135 depot_total=3866 total=44001 > [83483.457858] print_iova1 cpu_total=62532 depot_total=24476 total=87008 > > Where total IOVA rcache size has grown from 44K->87K over a long time. > > Along with this patch, I included the following: > - A smaller helper to clear all IOVAs for a domain > - Change polarity of the IOVA magazine helpers > - Small optimisation from Cong Wang included, which was never applied [1]. > There was some debate of the other patches in that series, but this one > is quite straightforward. > > Differnces to v2: > - Update commit message for patch 3/4 > > Differences to v1: > - Add IOVA clearing helper > - Add patch to change polarity of mag helpers > - Avoid logically-redundant extra variable in __iova_rcache_insert() > > [0] https://lore.kernel.org/linux-iommu/20190815121104.29140-3-thunder.leizhen@huawei.com/ > [1] https://lore.kernel.org/linux-iommu/4b74d40a-22d1-af53-fcb6-5d70183705a8@huawei.com/ > > Cong Wang (1): > iommu: avoid taking iova_rbtree_lock twice > > John Garry (3): > iommu/iova: Add free_all_cpu_cached_iovas() > iommu/iova: Avoid double-negatives in magazine helpers > iommu/iova: Flush CPU rcache for when a depot fills > > drivers/iommu/iova.c | 66 +++++++++++++++++++++++++------------------- > 1 file changed, 38 insertions(+), 28 deletions(-) >