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=-9.6 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT 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 ED8D7C33C8C for ; Fri, 29 Nov 2019 00:49:23 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id C2DF42176D for ; Fri, 29 Nov 2019 00:49:23 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="uv7cRYLr" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726764AbfK2AtX (ORCPT ); Thu, 28 Nov 2019 19:49:23 -0500 Received: from mail-pf1-f196.google.com ([209.85.210.196]:40772 "EHLO mail-pf1-f196.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726657AbfK2AtW (ORCPT ); Thu, 28 Nov 2019 19:49:22 -0500 Received: by mail-pf1-f196.google.com with SMTP id i187so9658036pfc.7 for ; Thu, 28 Nov 2019 16:49:22 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=from:to:cc:subject:date:message-id:in-reply-to:references :mime-version:content-transfer-encoding; bh=DpznRcuYAqspUUeo19X/byGcrul93mEcWyqODmZkSA8=; b=uv7cRYLrhvi/aOD4vOaTCjHBCFan3ldiAvc4IyTrphTn6qsfNGu9KJgLDPplUhhsNE 9rhYnafXvB2m+I68G52zwym3HOaI+9O3+crzu1sv+pykaitf0cs43RAKQwEY8ycEOZMA lX9jfVgIKz5YpPqOq0kuGSZTgXt2BDYcNcQVqSdiNt9xPdl0h1F1CphV+H8DfmXXCS1w TekYSCJVPgrsCgAi2pb8FqBfPsImxxi6ruIsbwJp1sGaeKZUZigQ3XzGPxvmmKodf41p LYSifRjh2RmQrwJmhHJIab+BDFz7f2MnCsz9zMT+0ZvxulqF5SNeaidw9uHSeZ8kixWP ZJQg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references:mime-version:content-transfer-encoding; bh=DpznRcuYAqspUUeo19X/byGcrul93mEcWyqODmZkSA8=; b=pLaD6e7A0c5s3URlTeWuRtM4jpCzBTgX5SJ7BPQHojtikXhMIlMrTHDzyLXdeVFhFz 5GnIrZQEPrLMj7U0UxirEDjaW+ML2C5QqD81biHJ5/k0hyKKOMT8Ho6fnKbuF1rkH8zl 3CYqDdTJp4LSYBt1sEMEd8oAoKEnc2FEwLtYNUciv6ft/O8qIfrQAiW0OmkLm9W32tjL 8+lM3/0ltoiOx6h+4oKSNlTkzuLCMBOl+6sqQr5ZKkVuy9YLpJjLuEcQE6xT3ju7qsTK HNIAny6hSTc3eVHJjlJScdUyUd0yRp2sjDH+uFwPQlYU8HkJINGLSVZFfiRR4RboY2Oz AyvA== X-Gm-Message-State: APjAAAVSHxxcXtffzTDrjOuGLut1Rn60zx4Hx5xDIlGj3V+7PNOlnedA gY2O5r12K96qwsdUUxt1BAg= X-Google-Smtp-Source: APXvYqxhJpBu3a7f3trFLsAjKcUtittnlOzHQt84mLjfEE/MmzfgbT5/Xbz5tchacpJvSgs10fMTqA== X-Received: by 2002:a63:5725:: with SMTP id l37mr14326615pgb.247.1574988561727; Thu, 28 Nov 2019 16:49:21 -0800 (PST) Received: from tw-172-25-31-76.office.twttr.net ([8.25.197.24]) by smtp.gmail.com with ESMTPSA id 64sm22418202pfe.147.2019.11.28.16.49.20 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 28 Nov 2019 16:49:21 -0800 (PST) From: Cong Wang To: iommu@lists.linux-foundation.org Cc: linux-kernel@vger.kernel.org, joro@8bytes.org, Cong Wang Subject: [Patch v2 3/3] iommu: avoid taking iova_rbtree_lock twice Date: Thu, 28 Nov 2019 16:48:55 -0800 Message-Id: <20191129004855.18506-4-xiyou.wangcong@gmail.com> X-Mailer: git-send-email 2.21.0 In-Reply-To: <20191129004855.18506-1-xiyou.wangcong@gmail.com> References: <20191129004855.18506-1-xiyou.wangcong@gmail.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Both find_iova() and __free_iova() take iova_rbtree_lock, there is no reason to take and release it twice inside free_iova(). Fold them into the critical section by calling the unlock versions instead. Cc: Joerg Roedel Signed-off-by: Cong Wang --- drivers/iommu/iova.c | 8 ++++++-- 1 file changed, 6 insertions(+), 2 deletions(-) diff --git a/drivers/iommu/iova.c b/drivers/iommu/iova.c index 184d4c0e20b5..f46f8f794678 100644 --- a/drivers/iommu/iova.c +++ b/drivers/iommu/iova.c @@ -390,10 +390,14 @@ EXPORT_SYMBOL_GPL(__free_iova); void free_iova(struct iova_domain *iovad, unsigned long pfn) { - struct iova *iova = find_iova(iovad, pfn); + unsigned long flags; + struct iova *iova; + spin_lock_irqsave(&iovad->iova_rbtree_lock, flags); + iova = private_find_iova(iovad, pfn); if (iova) - __free_iova(iovad, iova); + private_free_iova(iovad, iova); + spin_unlock_irqrestore(&iovad->iova_rbtree_lock, flags); } EXPORT_SYMBOL_GPL(free_iova); -- 2.21.0