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 Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by smtp.lore.kernel.org (Postfix) with ESMTP id 6202AC433F5 for ; Sat, 8 Oct 2022 12:21:31 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 547EF6B0072; Sat, 8 Oct 2022 08:21:30 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 4F7046B0073; Sat, 8 Oct 2022 08:21:30 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 3BEEA6B0074; Sat, 8 Oct 2022 08:21:30 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0017.hostedemail.com [216.40.44.17]) by kanga.kvack.org (Postfix) with ESMTP id 28C9C6B0072 for ; Sat, 8 Oct 2022 08:21:30 -0400 (EDT) Received: from smtpin04.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay02.hostedemail.com (Postfix) with ESMTP id F2653120C40 for ; Sat, 8 Oct 2022 12:21:29 +0000 (UTC) X-FDA: 79997692698.04.FE52C59 Received: from szxga02-in.huawei.com (szxga02-in.huawei.com [45.249.212.188]) by imf16.hostedemail.com (Postfix) with ESMTP id 34437180010 for ; Sat, 8 Oct 2022 12:21:25 +0000 (UTC) Received: from canpemm500002.china.huawei.com (unknown [172.30.72.54]) by szxga02-in.huawei.com (SkyGuard) with ESMTP id 4Ml4191YLFzVhvd; Sat, 8 Oct 2022 20:17:01 +0800 (CST) Received: from [10.174.151.185] (10.174.151.185) by canpemm500002.china.huawei.com (7.192.104.244) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2375.31; Sat, 8 Oct 2022 20:21:21 +0800 Subject: Re: [PATCH 1/1] mm/mmap_lock: Remove unnecessary 'NULL' values from Pointer To: XU pengfei CC: , , Andrew Morton References: <20221008093942.3982-1-xupengfei@nfschina.com> From: Miaohe Lin Message-ID: <45e6ce25-f0b6-4461-b88d-5b6bb78cabba@huawei.com> Date: Sat, 8 Oct 2022 20:21:21 +0800 User-Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:78.0) Gecko/20100101 Thunderbird/78.6.0 MIME-Version: 1.0 In-Reply-To: <20221008093942.3982-1-xupengfei@nfschina.com> Content-Type: text/plain; charset="utf-8" Content-Language: en-US Content-Transfer-Encoding: 7bit X-Originating-IP: [10.174.151.185] X-ClientProxiedBy: dggems706-chm.china.huawei.com (10.3.19.183) To canpemm500002.china.huawei.com (7.192.104.244) X-CFilter-Loop: Reflected ARC-Seal: i=1; s=arc-20220608; d=hostedemail.com; t=1665231689; a=rsa-sha256; cv=none; b=KvsdZieDR6FdGedESdg8hBIsvEXd5/htuVsY7fLhnE6K0n8O+XhU3FV8c59mpESVxp+cLn 2xBV31R+4fazgVmY1o/NDuC3qNVVBvYuFsLSM+fZJVgkOX+2pSuT+CUaSA5Xp6HdI6g/YC ahTR/ERYYTzRMMGIh+/E5Ml68wBav/A= ARC-Authentication-Results: i=1; imf16.hostedemail.com; dkim=none; dmarc=pass (policy=quarantine) header.from=huawei.com; spf=pass (imf16.hostedemail.com: domain of linmiaohe@huawei.com designates 45.249.212.188 as permitted sender) smtp.mailfrom=linmiaohe@huawei.com ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1665231689; h=from:from:sender:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=d9OwRu2Q3EhkQzcU3A0HNk4bT09RxkDelXCkhE9KYzQ=; b=nX339d9v3DVaErNLjU5hEK51a5cWNBrr+M7Slb47QzC5x3xYU0KhI/aEfV7tTSrRXW7Zao P9OqbbeQ3X7JHUBA87IK55SsMLcSwBcykRMvHDz/I3Cnecb7qP/6P/v8schz7lsk2F59If CVq60pF06MBV1Tnoo40FAFdQ0dF1HfE= X-Stat-Signature: a33fouwrrnw47ixfc5xngjhfyk5xp4fz X-Rspamd-Queue-Id: 34437180010 Authentication-Results: imf16.hostedemail.com; dkim=none; dmarc=pass (policy=quarantine) header.from=huawei.com; spf=pass (imf16.hostedemail.com: domain of linmiaohe@huawei.com designates 45.249.212.188 as permitted sender) smtp.mailfrom=linmiaohe@huawei.com X-Rspam-User: X-Rspamd-Server: rspam02 X-HE-Tag: 1665231685-378512 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: On 2022/10/8 17:39, XU pengfei wrote: > Pointer variables allocate memory first, and then judge. There is no > need to initialize the assignment. > > Signed-off-by: XU pengfei > --- > mm/mmap_lock.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/mm/mmap_lock.c b/mm/mmap_lock.c > index 1854850b4b89..65a57731aa15 100644 > --- a/mm/mmap_lock.c > +++ b/mm/mmap_lock.c > @@ -198,7 +198,7 @@ void trace_mmap_lock_unreg(void) > */ > static const char *get_mm_memcg_path(struct mm_struct *mm) > { > - char *buf = NULL; > + char *buf; > struct mem_cgroup *memcg = get_mem_cgroup_from_mm(mm); > > if (memcg == NULL) It seems if memcg == NULL, the code will go to out and return uninitialized @buf? Thanks, Miaohe Lin