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=-7.3 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,MENTIONS_GIT_HOSTING,SPF_HELO_NONE,SPF_PASS, USER_AGENT_SANE_1 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 B055EC4332B for ; Tue, 24 Mar 2020 09:18:30 +0000 (UTC) Received: from fraxinus.osuosl.org (smtp4.osuosl.org [140.211.166.137]) (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 7C5F720A8B for ; Tue, 24 Mar 2020 09:18:30 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 7C5F720A8B Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=huawei.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=iommu-bounces@lists.linux-foundation.org Received: from localhost (localhost [127.0.0.1]) by fraxinus.osuosl.org (Postfix) with ESMTP id 4BAF8861C9; Tue, 24 Mar 2020 09:18:30 +0000 (UTC) X-Virus-Scanned: amavisd-new at osuosl.org Received: from fraxinus.osuosl.org ([127.0.0.1]) by localhost (.osuosl.org [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id tdo1LXbTeErd; Tue, 24 Mar 2020 09:18:28 +0000 (UTC) Received: from lists.linuxfoundation.org (lf-lists.osuosl.org [140.211.9.56]) by fraxinus.osuosl.org (Postfix) with ESMTP id B7D5086155; Tue, 24 Mar 2020 09:18:28 +0000 (UTC) Received: from lf-lists.osuosl.org (localhost [127.0.0.1]) by lists.linuxfoundation.org (Postfix) with ESMTP id AC229C089F; Tue, 24 Mar 2020 09:18:28 +0000 (UTC) Received: from hemlock.osuosl.org (smtp2.osuosl.org [140.211.166.133]) by lists.linuxfoundation.org (Postfix) with ESMTP id 03A97C0177 for ; Tue, 24 Mar 2020 09:18:26 +0000 (UTC) Received: from localhost (localhost [127.0.0.1]) by hemlock.osuosl.org (Postfix) with ESMTP id E030C88928 for ; Tue, 24 Mar 2020 09:18:26 +0000 (UTC) X-Virus-Scanned: amavisd-new at osuosl.org Received: from hemlock.osuosl.org ([127.0.0.1]) by localhost (.osuosl.org [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id xbLL7vsGWi6B for ; Tue, 24 Mar 2020 09:18:25 +0000 (UTC) X-Greylist: domain auto-whitelisted by SQLgrey-1.7.6 Received: from huawei.com (lhrrgout.huawei.com [185.176.76.210]) by hemlock.osuosl.org (Postfix) with ESMTPS id C174E88927 for ; Tue, 24 Mar 2020 09:18:25 +0000 (UTC) Received: from lhreml702-cah.china.huawei.com (unknown [172.18.7.108]) by Forcepoint Email with ESMTP id DA4C5305CE469B927D24; Tue, 24 Mar 2020 09:18:22 +0000 (GMT) Received: from lhreml724-chm.china.huawei.com (10.201.108.75) by lhreml702-cah.china.huawei.com (10.201.108.43) with Microsoft SMTP Server (TLS) id 14.3.408.0; Tue, 24 Mar 2020 09:18:22 +0000 Received: from [127.0.0.1] (10.210.165.24) 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 15.1.1713.5; Tue, 24 Mar 2020 09:18:21 +0000 Subject: Re: arm-smmu-v3 high cpu usage for NVMe To: Marc Zyngier References: <20190821151749.23743-1-will@kernel.org> <20200318205313.GB8094@willie-the-truck> <20200319184349.GA1697676@myrica> <20200320111842.GD1702630@myrica> <5198fcffc8ad6233e0274ebff9e9aa5f@kernel.org> From: John Garry Message-ID: <0e00de15-596a-d342-f3cb-e19c389294e6@huawei.com> Date: Tue, 24 Mar 2020 09:18:10 +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: Content-Language: en-US X-Originating-IP: [10.210.165.24] X-ClientProxiedBy: lhreml732-chm.china.huawei.com (10.201.108.83) To lhreml724-chm.china.huawei.com (10.201.108.75) X-CFilter-Loop: Reflected Cc: Mark Rutland , Jean-Philippe Brucker , Robin Murphy , Ming Lei , iommu@lists.linux-foundation.org, Will Deacon , Julien Thierry X-BeenThere: iommu@lists.linux-foundation.org X-Mailman-Version: 2.1.15 Precedence: list List-Id: Development issues for Linux IOMMU support List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Transfer-Encoding: 7bit Content-Type: text/plain; charset="us-ascii"; Format="flowed" Errors-To: iommu-bounces@lists.linux-foundation.org Sender: "iommu" On 23/03/2020 09:16, Marc Zyngier wrote: + Julien, Mark Hi Marc, >>> Time to enable pseudo-NMIs in the PMUv3 driver... >>> >> >> Do you know if there is any plan for this? > > There was. Julien Thierry has a bunch of patches for that [1], but they > needs > reviving. > So those patches still apply cleanly (apart from the kvm patch, which I can skip, I suppose) and build, so I can try this I figure. Is there anything else which I should ensure or know about? Apart from enable CONFIG_ARM64_PSUEDO_NMI. A quickly taken perf annotate and report is at the tip here: https://github.com/hisilicon/kernel-dev/commits/private-topic-nvme-5.6-profiling >> >> In the meantime, maybe I can do some trickery by putting the >> local_irq_restore() in a separate function, outside >> arm_smmu_cmdq_issue_cmdlist(), to get a fair profile for that same >> function. > Scratch that :) > I don't see how you can improve the profiling without compromising > the locking in this case... > Cheers, John [1] https://patchwork.kernel.org/cover/11047407/ _______________________________________________ iommu mailing list iommu@lists.linux-foundation.org https://lists.linuxfoundation.org/mailman/listinfo/iommu