From nobody Mon Apr 27 04:32:35 2026 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 1ED10C43334 for ; Fri, 17 Jun 2022 08:38:54 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1381017AbiFQIiw (ORCPT ); Fri, 17 Jun 2022 04:38:52 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:50556 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1380352AbiFQIio (ORCPT ); Fri, 17 Jun 2022 04:38:44 -0400 Received: from mail-pf1-x42c.google.com (mail-pf1-x42c.google.com [IPv6:2607:f8b0:4864:20::42c]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 1A52369298 for ; Fri, 17 Jun 2022 01:38:39 -0700 (PDT) Received: by mail-pf1-x42c.google.com with SMTP id u37so3622370pfg.3 for ; Fri, 17 Jun 2022 01:38:39 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20210112; h=from:to:cc:subject:date:message-id:mime-version :content-transfer-encoding; bh=Ak/3+BuQZPayyHcZgGcyHRrIZ/8v8tKL6L3S32n4JYk=; b=EpUGberfrYQ9nVCS5lYRWlTyhUO4ZoVu1Da8yhexf+xots8csRHJG8I1O0kr08bTiK UyFMjNP3Dpv1TrfycA7YM55pgJMT7wBkAZWSPbpZZh212nLXRV8GCL8cAqyMdlhwSs3P qRbPWlbxQoZzLBe1qsPs/XMlyF3ctrxxvHAjSWOyZppO0eF8dF+BKJvl/BzCayYqwIxE FxCC0GhNlmzjz1yAfrzAHSsWIoCjmgRI0TNH2LToGN2YpsvIQoBL0AT1g7YiU6fPjXJ1 SqbJCO1d5IYbC21C8UykgyOC6MQQx2pbL8Ol+aZYiPfm2tfaWGyYkC7O181ltBe1UADg d95Q== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:from:to:cc:subject:date:message-id:mime-version :content-transfer-encoding; bh=Ak/3+BuQZPayyHcZgGcyHRrIZ/8v8tKL6L3S32n4JYk=; b=tRXvfxWekPrXHwaiqVPPRJ98BEvjF9ndSj9IyUU1PkqlP36sRyI378/SvsLZn0Be6h ri9ajPaV0svH5bgg/YT0sntxljEeTfex/qa4uS59St0cYqF+vRmTBN4CN189vacWsNyY fA/NlwlekNgLTSfXheDyU4vOsJB7luNqjQ57m2yiXFet4H6s7t2oEEDSs8GazQjbpMBP s2Ykz9o8X2RrXQKeQy51D2exJUFIObNCkVCX42c+tA610aas8SoyuPWyK3wkNlYqY8z2 +BmnSNOg9MF93nhWrPtMDdOSJe33UCJoTF5A4KdqyppeWWDTgBJfa9seKhoZ/riqSyHU 4dnw== X-Gm-Message-State: AJIora+VJzf1Fd/B8gpncM2rTsOqGfeg9A4OrD/qyGp1VJGW5qlAgKIb 2y4IMC5YsBsduT4WZzfedPigZaAf/BuJewch3pM= X-Google-Smtp-Source: AGRyM1sML4mzdm2IzfHLLLIFa1pM+mhWo+dk8gDIqG/7wtIC5Vr0Pb47JfVpwWQ8v4Ta/5cP6D8P9A== X-Received: by 2002:a62:7cca:0:b0:4fd:e594:fac0 with SMTP id x193-20020a627cca000000b004fde594fac0mr8931045pfc.79.1655455118327; Fri, 17 Jun 2022 01:38:38 -0700 (PDT) Received: from localhost.localdomain ([139.177.225.254]) by smtp.gmail.com with ESMTPSA id z14-20020a170902ccce00b001635b86a790sm2988179ple.44.2022.06.17.01.38.36 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Fri, 17 Jun 2022 01:38:37 -0700 (PDT) From: wuchi To: gregkh@linuxfoundation.org, rafael@kernel.org Cc: linux-kernel@vger.kernel.org Subject: [PATCH] lib/kobject: Simplify checking of parameters in kobj_ns_type_register. Date: Fri, 17 Jun 2022 16:38:32 +0800 Message-Id: <20220617083832.85287-1-wuchi.zero@gmail.com> X-Mailer: git-send-email 2.32.0 (Apple Git-132) MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Type: text/plain; charset="utf-8" 1. Merge checking of following code: if (type >=3D KOBJ_NS_TYPES) ... if (type <=3D KOBJ_NS_TYPE_NONE) 2. Move the checking of parameters out of critical section, there is no need to check that with spinlock. Signed-off-by: wuchi --- lib/kobject.c | 14 ++++---------- 1 file changed, 4 insertions(+), 10 deletions(-) diff --git a/lib/kobject.c b/lib/kobject.c index 5f0e71ab292c..6a8b009682b8 100644 --- a/lib/kobject.c +++ b/lib/kobject.c @@ -996,19 +996,13 @@ static const struct kobj_ns_type_operations *kobj_ns_= ops_tbl[KOBJ_NS_TYPES]; int kobj_ns_type_register(const struct kobj_ns_type_operations *ops) { enum kobj_ns_type type =3D ops->type; - int error; - - spin_lock(&kobj_ns_type_lock); + int error =3D -EBUSY; =20 - error =3D -EINVAL; - if (type >=3D KOBJ_NS_TYPES) - goto out; + if (unlikely(type >=3D KOBJ_NS_TYPES || type <=3D KOBJ_NS_TYPE_NONE)) + return -EINVAL; =20 - error =3D -EINVAL; - if (type <=3D KOBJ_NS_TYPE_NONE) - goto out; + spin_lock(&kobj_ns_type_lock); =20 - error =3D -EBUSY; if (kobj_ns_ops_tbl[type]) goto out; =20 --=20 2.20.1