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=-7.0 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_PASS,URIBL_BLOCKED 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 26A7EC43444 for ; Sat, 29 Dec 2018 10:02:29 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id E31802145D for ; Sat, 29 Dec 2018 10:02:28 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=messagingengine.com header.i=@messagingengine.com header.b="KaWkSNJM" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729222AbeL2KC2 (ORCPT ); Sat, 29 Dec 2018 05:02:28 -0500 Received: from out1-smtp.messagingengine.com ([66.111.4.25]:48319 "EHLO out1-smtp.messagingengine.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726737AbeL2KC1 (ORCPT ); Sat, 29 Dec 2018 05:02:27 -0500 Received: from compute4.internal (compute4.nyi.internal [10.202.2.44]) by mailout.nyi.internal (Postfix) with ESMTP id 6F1CA21CCA; Sat, 29 Dec 2018 05:02:24 -0500 (EST) Received: from mailfrontend1 ([10.202.2.162]) by compute4.internal (MEProxy); Sat, 29 Dec 2018 05:02:24 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d= messagingengine.com; h=cc:content-transfer-encoding:content-type :date:from:in-reply-to:message-id:mime-version:references :subject:to:x-me-proxy:x-me-proxy:x-me-sender:x-me-sender :x-sasl-enc; s=fm1; bh=G6Xp2/+N8BFhpfIvek7LJpWLo8ioC8eE7s6mAK/Uk To=; b=KaWkSNJMRSs3YiXBdZxUNH69HZC+jvcQ60vrZz9MDjM1Wc1x5HhPrvhxO V3pUbcpw8mLvf3iruUr08kwnPLsTg8OKOLVHxxdt3xoNk2YndhegZmMffc/pULIK njvkWv41M0FL2XS03pBX2SCMyKnYk2PAHMz6S3iBcz2sjF2MvBjizk6UvHN7bk/O FXHrHUaUBU8zK7SCKAs22c0ZCJmYAOFEVornxLrICeEKZL8QMYLrCiNkp8l1QA2l DIVIrpAa9O7DZSn+jzbg6ng+0DaYgoYl017yoRXCngrIDx8DDfN7ebeOIS523WTE n6LUduQftvAC7V0nhs6CTDGIXP+dw== X-ME-Sender: X-ME-Proxy-Cause: gggruggvucftvghtrhhoucdtuddrgedtledrtdekgdduudculddtuddrgedtkedrtddtmd cutefuodetggdotefrodftvfcurfhrohhfihhlvgemucfhrghsthforghilhdpqfhuthen uceurghilhhouhhtmecufedttdenucenucfjughrpefuvfhfhffkffgfgggjtgfgsehtje ertddtfeejnecuhfhrohhmpefrvghkkhgrucfgnhgsvghrghcuoehpvghnsggvrhhgsehi khhirdhfiheqnecukfhppeekledrvdejrdeffedrudejfeenucfrrghrrghmpehmrghilh hfrhhomhepphgvnhgsvghrghesihhkihdrfhhinecuvehluhhsthgvrhfuihiivgeptd X-ME-Proxy: Received: from Pekka-MacBook.local (89-27-33-173.bb.dnainternet.fi [89.27.33.173]) by mail.messagingengine.com (Postfix) with ESMTPA id 21578E459A; Sat, 29 Dec 2018 05:02:19 -0500 (EST) Subject: Re: [PATCH] mm/slub.c: freelist is ensured to be NULL when new_slab() fails To: Peng Wang , cl@linux.com, penberg@kernel.org, rientjes@google.com, iamjoonsoo.kim@lge.com, akpm@linux-foundation.org Cc: linux-mm@kvack.org, linux-kernel@vger.kernel.org References: <20181229062512.30469-1-rocking@whu.edu.cn> From: Pekka Enberg Message-ID: <56ee5ac0-0785-cf2a-c1b4-95d4df2d11f1@iki.fi> Date: Sat, 29 Dec 2018 12:02:14 +0200 User-Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10.12; rv:60.0) Gecko/20100101 Thunderbird/60.3.3 MIME-Version: 1.0 In-Reply-To: <20181229062512.30469-1-rocking@whu.edu.cn> Content-Type: text/plain; charset=utf-8; format=flowed Content-Language: en-US Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 29/12/2018 8.25, Peng Wang wrote: > new_slab_objects() will return immediately if freelist is not NULL. > > if (freelist) > return freelist; > > One more assignment operation could be avoided. > > Signed-off-by: Peng Wang Reviewed-by: Pekka Enberg > --- > mm/slub.c | 3 +-- > 1 file changed, 1 insertion(+), 2 deletions(-) > > diff --git a/mm/slub.c b/mm/slub.c > index 36c0befeebd8..cf2ef4ababff 100644 > --- a/mm/slub.c > +++ b/mm/slub.c > @@ -2463,8 +2463,7 @@ static inline void *new_slab_objects(struct kmem_cache *s, gfp_t flags, > stat(s, ALLOC_SLAB); > c->page = page; > *pc = c; > - } else > - freelist = NULL; > + } > > return freelist; > } >