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,URIBL_BLOCKED,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 54C7CC432C0 for ; Thu, 21 Nov 2019 00:14:35 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 295E720885 for ; Thu, 21 Nov 2019 00:14:35 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="PmTUpgmc" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726784AbfKUAOd (ORCPT ); Wed, 20 Nov 2019 19:14:33 -0500 Received: from mail-pf1-f195.google.com ([209.85.210.195]:32924 "EHLO mail-pf1-f195.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726568AbfKUAO2 (ORCPT ); Wed, 20 Nov 2019 19:14:28 -0500 Received: by mail-pf1-f195.google.com with SMTP id c184so667052pfb.0 for ; Wed, 20 Nov 2019 16:14:27 -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=udQXwBqwVUeF6xC6dQa8BSO4hgjarlIB0Nc7lZHwUEA=; b=PmTUpgmcsZD3GF/gHlUVnQ7Wd6qGzBXJRebg41O5KVp5B4SGj1iQoNT6vrG16K1vWv PMW+ss1KwBjjxcowPxX0G5tfmjwtDcoxYWSqXxGzroRbZ7+ReUh5wNat1j67hfHawzPy l5xUJpSiqCwH+BdW8gVIEMDYEv6S6X4xCId+oIOFcRvlf50SDCGE9o58neccf4tXAnEs Sz62fIvYg0WHp4Ade1Vfm0ToGQ26feG2MYMWjgmrAn+xJweDd/aN43V5GrGNfAS+ga9X VrjormozWMpTexqanVuLBV1MtPIsvqzloBjV4DEdsDLZT2uNeWG32eNAsY1glpl9Humz gGKA== 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=udQXwBqwVUeF6xC6dQa8BSO4hgjarlIB0Nc7lZHwUEA=; b=MDb2fdDv184WU+NP6o4S/MFWg0XIpf1M6Mt1QHvqnZHtQlPkSLOhfKfeIN/O1rxv3b uMXb/cL1AeE4eqS0Na3EPCz5Ubz6QZOdQeUeXnky9uC35g4wqal9jsHxrcXGkVGYNzT9 VZkWhA2ztP4fSdkeEYF1n8x82GC7aqssAB4oK8wFIbrB3Oa3YFnVgI1yhZ6YYfwrjwFQ zd2rq2w+a3jc2BH69gLlOv3WNeuE2J+EzZT6IsBaxHgpj6exigZzOytc630fC6yhlHdK 7IB3XyY4XnpqDahiBd+8q5BY7144HYjUiz5SS1LnVo24QUopUUSvQ01AL5liSj395Duq g0gA== X-Gm-Message-State: APjAAAWsaF3Oy/mQVJlyieLYk7BlCryPdue/KNN99aDvngC9O+Jzba5g 74fOED4I1s2VA1oiO3wEdXL9iYV97Bs= X-Google-Smtp-Source: APXvYqx70jN/lPvZpOJJEJjwiAVrjv2LEdf58Rsl9gZ8a1GGPTbJPowBV+wmAhPAjJGY0xKjB0p9Ag== X-Received: by 2002:a63:5551:: with SMTP id f17mr6048190pgm.287.1574295267007; Wed, 20 Nov 2019 16:14:27 -0800 (PST) Received: from tw-172-25-31-76.office.twttr.net ([8.25.197.24]) by smtp.gmail.com with ESMTPSA id r4sm565981pfl.61.2019.11.20.16.14.26 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 20 Nov 2019 16:14:26 -0800 (PST) From: Cong Wang To: iommu@lists.linux-foundation.org Cc: linux-kernel@vger.kernel.org, joro@8bytes.org, Cong Wang Subject: [PATCH 3/3] iommu: avoid taking iova_rbtree_lock twice Date: Wed, 20 Nov 2019 16:13:48 -0800 Message-Id: <20191121001348.27230-4-xiyou.wangcong@gmail.com> X-Mailer: git-send-email 2.21.0 In-Reply-To: <20191121001348.27230-1-xiyou.wangcong@gmail.com> References: <20191121001348.27230-1-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 b82c6f1cbfc2..ba6bd33f2b16 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