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=-12.9 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS, UNPARSEABLE_RELAY,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 91C36C433E1 for ; Tue, 18 Aug 2020 15:56:21 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 66F9D20829 for ; Tue, 18 Aug 2020 15:56:21 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=oracle.com header.i=@oracle.com header.b="Q3h4vJ3O" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728361AbgHRP4N (ORCPT ); Tue, 18 Aug 2020 11:56:13 -0400 Received: from userp2130.oracle.com ([156.151.31.86]:40640 "EHLO userp2130.oracle.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728191AbgHRPr1 (ORCPT ); Tue, 18 Aug 2020 11:47:27 -0400 Received: from pps.filterd (userp2130.oracle.com [127.0.0.1]) by userp2130.oracle.com (8.16.0.42/8.16.0.42) with SMTP id 07IFSQTD006892; Tue, 18 Aug 2020 15:47:24 GMT DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=oracle.com; h=from : to : cc : subject : date : message-id : mime-version : content-transfer-encoding; s=corp-2020-01-29; bh=F6Oi0mM4LViFiJsPNqjBUOhmIWktb+jsw3EHBlvgXMg=; b=Q3h4vJ3Oco+MRw0Vn0W3t9xOSix3PSEVPcy+sv2EnucTq/Ab1+dUu2Up3SEqh48aFxwn MahDLpZahUM525g9IXSsbSOp/NA4R3PfemCzgvYNUNztm2GfBL8m9p8RCO0cKmhZ/7Ll QMm/h2ngvvGe+jLqzMB93fEv/78HkFdUFxhEy5XART1aVA1mqajUv/95ptoki2GJjIGg o8gwaAjYeVTSXWy2olXiBMD9uKuSpHYvNHH+AWp+wDbEBYQRRY0Uz82QvkCsNAjZvtke aqXLNgGqkFRg0yZpNKYqH1Fx6kiFDvE9yiU79vi39T88RiIdO3HmEXtIUd2D6I11T72D qw== Received: from aserp3020.oracle.com (aserp3020.oracle.com [141.146.126.70]) by userp2130.oracle.com with ESMTP id 32x74r5q5y-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=FAIL); Tue, 18 Aug 2020 15:47:24 +0000 Received: from pps.filterd (aserp3020.oracle.com [127.0.0.1]) by aserp3020.oracle.com (8.16.0.42/8.16.0.42) with SMTP id 07IFY09d027332; Tue, 18 Aug 2020 15:47:23 GMT Received: from aserv0121.oracle.com (aserv0121.oracle.com [141.146.126.235]) by aserp3020.oracle.com with ESMTP id 32xsm35pey-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Tue, 18 Aug 2020 15:47:23 +0000 Received: from abhmp0001.oracle.com (abhmp0001.oracle.com [141.146.116.7]) by aserv0121.oracle.com (8.14.4/8.13.8) with ESMTP id 07IFlMxo032678; Tue, 18 Aug 2020 15:47:22 GMT Received: from revolver.jebus.ca (/23.233.25.87) by default (Oracle Beehive Gateway v4.0) with ESMTP ; Tue, 18 Aug 2020 08:47:22 -0700 From: "Liam R. Howlett" To: Andrew Morton Cc: linux-mm@kvack.org, linux-kernel@vger.kernel.org, Liam.Howlett@Oracle.com Subject: [PATCH 1/2] mm/mmap: Add inline vma_next() for readability of mmap code Date: Tue, 18 Aug 2020 11:47:06 -0400 Message-Id: <20200818154707.2515169-1-Liam.Howlett@Oracle.com> X-Mailer: git-send-email 2.28.0 MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Proofpoint-Virus-Version: vendor=nai engine=6000 definitions=9716 signatures=668679 X-Proofpoint-Spam-Details: rule=notspam policy=default score=0 adultscore=0 suspectscore=0 malwarescore=0 mlxscore=0 phishscore=0 spamscore=0 mlxlogscore=999 bulkscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-2006250000 definitions=main-2008180112 X-Proofpoint-Virus-Version: vendor=nai engine=6000 definitions=9716 signatures=668679 X-Proofpoint-Spam-Details: rule=notspam policy=default score=0 impostorscore=0 mlxlogscore=999 priorityscore=1501 phishscore=0 spamscore=0 mlxscore=0 adultscore=0 suspectscore=0 lowpriorityscore=0 bulkscore=0 malwarescore=0 clxscore=1011 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-2006250000 definitions=main-2008180112 Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org There are three places that the next vma is required which uses the same block of code. Replace the block with a function and add comments on what happens in the case where NULL is encountered. Signed-off-by: Liam R. Howlett --- mm/mmap.c | 26 ++++++++++++++++++++------ 1 file changed, 20 insertions(+), 6 deletions(-) diff --git a/mm/mmap.c b/mm/mmap.c index 40248d84ad5fb..6026353035966 100644 --- a/mm/mmap.c +++ b/mm/mmap.c @@ -560,6 +560,23 @@ static int find_vma_links(struct mm_struct *mm, unsigned long addr, return 0; } +/* + * vma_next() - Get the next VMA. + * @mm: The mm_struct. + * @vma: The current vma. + * + * If @vma is NULL, return the first vma in the mm. + * + * Returns: The next VMA after @vma. + */ +static inline struct vm_area_struct *vma_next(struct mm_struct *mm, + struct vm_area_struct *vma) +{ + if (!vma) + return mm->mmap; + + return vma->vm_next; +} static unsigned long count_vma_pages_range(struct mm_struct *mm, unsigned long addr, unsigned long end) { @@ -1131,10 +1148,7 @@ struct vm_area_struct *vma_merge(struct mm_struct *mm, if (vm_flags & VM_SPECIAL) return NULL; - if (prev) - next = prev->vm_next; - else - next = mm->mmap; + next = vma_next(mm, prev); area = next; if (area && area->vm_end == end) /* cases 6, 7, 8 */ next = next->vm_next; @@ -2625,7 +2639,7 @@ static void unmap_region(struct mm_struct *mm, struct vm_area_struct *vma, struct vm_area_struct *prev, unsigned long start, unsigned long end) { - struct vm_area_struct *next = prev ? prev->vm_next : mm->mmap; + struct vm_area_struct *next = vma_next(mm, prev); struct mmu_gather tlb; lru_add_drain(); @@ -2824,7 +2838,7 @@ int __do_munmap(struct mm_struct *mm, unsigned long start, size_t len, if (error) return error; } - vma = prev ? prev->vm_next : mm->mmap; + vma = vma_next(mm, prev); if (unlikely(uf)) { /* -- 2.28.0