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=-5.2 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, USER_AGENT_SANE_1 autolearn=no 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 B0A85C2D0A8 for ; Tue, 29 Sep 2020 01:21:24 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 6515F2083B for ; Tue, 29 Sep 2020 01:21:24 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="dB5AkSvg" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727077AbgI2BVV (ORCPT ); Mon, 28 Sep 2020 21:21:21 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:56132 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725272AbgI2BVV (ORCPT ); Mon, 28 Sep 2020 21:21:21 -0400 Received: from mail-pg1-x544.google.com (mail-pg1-x544.google.com [IPv6:2607:f8b0:4864:20::544]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id E8544C061755; Mon, 28 Sep 2020 18:21:20 -0700 (PDT) Received: by mail-pg1-x544.google.com with SMTP id y14so2447046pgf.12; Mon, 28 Sep 2020 18:21:20 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=date:from:to:cc:subject:message-id:references:mime-version :content-disposition:in-reply-to:user-agent; bh=LJ2EaLyywMeQ220DXk/3m8ij2UCaXBFliElieIvVcWo=; b=dB5AkSvgSsuC4jqhJi1Du6fOX/N7Xqa7co1RAVRI7k5jGv6Bykuo2tOZ/hkkel3qzY CTS8a/Oal7MbkDg+kiT/tRhuH74Nl3g/7dKHJijJyXGtbC8AlTGjsR/d9vYzi2kf/nR1 4oizg3sYkVtgATl4O58g0KvM7Gi3/4ZWup+Dxtczp0wmPtnV6YAR/bIsw1Er0jVGTujr NNzOmFB+JjELoSImcu53H6HFX6UmQpQGSgK396wSboSVx3JwNZhGUL6f5QLWlLhJ7BnP +5ITYJYN8klNUwbH3449wW7mMwZp0FIU8cp32Es6bcaZnfwrQWbNiFOcq4eUzNCZ4vzR wOgA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:from:to:cc:subject:message-id:references :mime-version:content-disposition:in-reply-to:user-agent; bh=LJ2EaLyywMeQ220DXk/3m8ij2UCaXBFliElieIvVcWo=; b=P0ViIyE0a9OKkXP4akBguDBhzAoXS+l+4pwXMv7AvMMF4747k6LyB/9qQiS1REfsO/ VW234KOQo4TClX05ShRyNMH3xlaA/CW0uvXlhvmtREXA4zC9xft1PjEB4k5REnFnZV3R JLeZoxU7y9Fx1cqZOl9QkHTMizuh7ur1mq9K6dQTRdCUuZLUpVVNKUPAjSO5PkJS/k13 2usqoDXBwvJi5OPfQt/vDr4T3U587XVvlGEI8mmDyumnpeMShBEqpSXOHJIVLBxzQrIj EDJ0IW5d/nk1xS1kUhWfROxPutSx31bMGMndtCWwxve5I3cWIgXWLLS+xFJ8LZiG9/+M Yxhg== X-Gm-Message-State: AOAM530IQQ71Pq+LSCSDWyR5ux7UAAdQU2WNAzjXvkqAU3vvFzljZy8F eTruV20cK2tklYrxbULYOSg= X-Google-Smtp-Source: ABdhPJyImG3w8frEfpcUQx/Q4jWtb4RC9mBhFFjza2RqlH0U2v8tnaw3/b8ogIZGHZf/614y9A889w== X-Received: by 2002:a17:902:b685:b029:d2:1e62:4cbe with SMTP id c5-20020a170902b685b02900d21e624cbemr2075538pls.58.1601342477766; Mon, 28 Sep 2020 18:21:17 -0700 (PDT) Received: from Asurada-Nvidia (thunderhill.nvidia.com. [216.228.112.22]) by smtp.gmail.com with ESMTPSA id d25sm2589760pgl.23.2020.09.28.18.21.17 (version=TLS1_2 cipher=ECDHE-ECDSA-CHACHA20-POLY1305 bits=256/256); Mon, 28 Sep 2020 18:21:17 -0700 (PDT) Date: Mon, 28 Sep 2020 18:15:57 -0700 From: Nicolin Chen To: Dmitry Osipenko Cc: thierry.reding@gmail.com, joro@8bytes.org, vdumpa@nvidia.com, jonathanh@nvidia.com, linux-tegra@vger.kernel.org, iommu@lists.linux-foundation.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH v2 2/2] iommu/tegra-smmu: Expend mutex protection range Message-ID: <20200929011557.GA905@Asurada-Nvidia> References: <20200928235901.28337-1-nicoleotsuka@gmail.com> <20200928235901.28337-3-nicoleotsuka@gmail.com> <692b51fa-7a3e-dee7-b628-7cb2d2dc188d@gmail.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <692b51fa-7a3e-dee7-b628-7cb2d2dc188d@gmail.com> User-Agent: Mutt/1.9.4 (2018-02-28) Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, Sep 29, 2020 at 03:17:58AM +0300, Dmitry Osipenko wrote: > ... > > static bool tegra_smmu_capable(enum iommu_cap cap) > > @@ -420,17 +413,21 @@ static int tegra_smmu_as_prepare(struct tegra_smmu *smmu, > > struct tegra_smmu_as *as) > > { > > u32 value; > > - int err; > > + int err = 0; > > + > > + mutex_lock(&smmu->lock); > > > > if (as->use_count > 0) { > > as->use_count++; > > - return 0; > > + goto err_unlock; > > This looks a bit odd because it's not a error condition. Perhaps should > be better to "goto bump_usecount"? > > Or make it similar to tegra_smmu_as_unprepare()? Hmm...I think it's simple to just make it "goto unlock" then.