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 097B3C3F68F for ; Wed, 18 Dec 2019 04:40:31 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id CFB2520715 for ; Wed, 18 Dec 2019 04:40:30 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="fSA6/OU6" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726699AbfLREk3 (ORCPT ); Tue, 17 Dec 2019 23:40:29 -0500 Received: from mail-pf1-f196.google.com ([209.85.210.196]:41569 "EHLO mail-pf1-f196.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726613AbfLREkV (ORCPT ); Tue, 17 Dec 2019 23:40:21 -0500 Received: by mail-pf1-f196.google.com with SMTP id w62so488907pfw.8 for ; Tue, 17 Dec 2019 20:40:21 -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=buvyJgIJY0R4gHfuaJpwEN38gwzHGwHEA+PtuFw57xs=; b=fSA6/OU6RZ4QSFkEveLrXMk7xfGo5Yml/4SapAlwGdyCNgt6hZvHpVJXueStFSsHRU E8cFUeFs80hq2ijU88iVgMzJbyAijs5ff9wE+NkkPiF2iJ9XGAthOz03SFgeQWN93Knc sxUokcCF+H9YitQqotepfn0/Z+vKvmrvDGp4PEfaS7oVzHaxx05dJjcuH1bLCw0F3GqB lBkVZB4XUJaRNgt7fr2Hd2Q8sbpoGUwVLYsgo6nGcVoUf+zHKWshZZBBA+L+Wcw3OsUZ B1eLZ2zD8Fs8xMcZ7wPwo4dThIhjfnksWJgczgKpxlIh5m6nPrk12rGDUrhJgCbdp9tY aWLg== 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=buvyJgIJY0R4gHfuaJpwEN38gwzHGwHEA+PtuFw57xs=; b=IkfY01iVJ7ZmLkyiNSE1JPsqH2NwOsUCynbNvq18tmSKUDBr06ucJp4Dahjo0RXr/n VFrV1XdUt5gmB1d6VFxnSh9OlZAfqCkCdlfrflvU2VxZCz26STKQzi/rrNjTDD7GIcQ+ n+uD0fILEAAHvuG5ITNbeK8MBreIka9U+eIpcC78XDLNt2lbv4wsJ06NOa86bErzatc5 LKhqNXGQjAgTFuQihX8djKBw5MmQsInPoP+hTAotx1DdRk5WEd1k8NB92EoSq+5H0hZy xCUHIZGA4tZmj8xkyRM/DHLYLfR6T7TMUcqvi9y7ncMmH9q/6AMYLJzCuR/+Nubavxwx IpEA== X-Gm-Message-State: APjAAAVBFxqN1Mlb6vd4uhHycpbrBc47p+zIHmpA0StJ0mk3fr7+lHJY 2I5h9aArInZG3DBlPdTIc6E= X-Google-Smtp-Source: APXvYqzYkNMV1tAM39yw129obSP47Du+yTcT5HVPg0cGDvNIcUAUzXmE7cRKZdrBA9z1l687aXPNXA== X-Received: by 2002:a62:8205:: with SMTP id w5mr831686pfd.136.1576644020754; Tue, 17 Dec 2019 20:40:20 -0800 (PST) Received: from tw-172-25-31-76.office.twttr.net ([8.25.197.24]) by smtp.gmail.com with ESMTPSA id j21sm781105pfe.175.2019.12.17.20.40.19 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 17 Dec 2019 20:40:20 -0800 (PST) From: Cong Wang To: iommu@lists.linux-foundation.org Cc: robin.murphy@arm.com, linux-kernel@vger.kernel.org, joro@8bytes.org, Cong Wang , John Garry Subject: [Patch v3 3/3] iommu: avoid taking iova_rbtree_lock twice Date: Tue, 17 Dec 2019 20:39:51 -0800 Message-Id: <20191218043951.10534-4-xiyou.wangcong@gmail.com> X-Mailer: git-send-email 2.21.0 In-Reply-To: <20191218043951.10534-1-xiyou.wangcong@gmail.com> References: <20191218043951.10534-1-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 one critical section by calling the unlock versions instead. Cc: Joerg Roedel Cc: John Garry 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