From patchwork Sat Oct 17 23:14:06 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Andrew Morton X-Patchwork-Id: 11843099 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 66E0014B5 for ; Sat, 17 Oct 2020 23:14:10 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id 2914B208E4 for ; Sat, 17 Oct 2020 23:14:10 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=kernel.org header.i=@kernel.org header.b="qxWpwbQ7" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 2914B208E4 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=linux-foundation.org Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id 1D2946B007B; Sat, 17 Oct 2020 19:14:09 -0400 (EDT) Delivered-To: linux-mm-outgoing@kvack.org Received: by kanga.kvack.org (Postfix, from userid 40) id 1813A6B007D; Sat, 17 Oct 2020 19:14:09 -0400 (EDT) X-Original-To: int-list-linux-mm@kvack.org X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 0C0406B007E; Sat, 17 Oct 2020 19:14:09 -0400 (EDT) X-Original-To: linux-mm@kvack.org X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0115.hostedemail.com [216.40.44.115]) by kanga.kvack.org (Postfix) with ESMTP id D0C146B007B for ; Sat, 17 Oct 2020 19:14:08 -0400 (EDT) Received: from smtpin22.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay04.hostedemail.com (Postfix) with ESMTP id 77E191EE6 for ; Sat, 17 Oct 2020 23:14:08 +0000 (UTC) X-FDA: 77382972576.22.glue45_601108927229 Received: from filter.hostedemail.com (10.5.16.251.rfc1918.com [10.5.16.251]) by smtpin22.hostedemail.com (Postfix) with ESMTP id 3849D18038E60 for ; Sat, 17 Oct 2020 23:14:08 +0000 (UTC) X-Spam-Summary: 1,0,0,d0412edb6cea0cd2,d41d8cd98f00b204,akpm@linux-foundation.org,,RULES_HIT:41:355:379:800:960:967:973:988:989:1260:1263:1345:1359:1381:1431:1437:1534:1542:1711:1730:1747:1777:1792:2393:2525:2559:2563:2682:2685:2859:2902:2933:2937:2939:2942:2945:2947:2951:2954:3022:3138:3139:3140:3141:3142:3353:3865:3866:3868:3870:3871:3874:3934:3936:3938:3941:3944:3947:3950:3953:3956:3959:4250:4321:5007:6261:6653:7576:8599:9025:9545:10004:10913:11026:11658:11914:12043:12048:12291:12296:12297:12438:12517:12519:12555:12679:12783:12986:13141:13161:13229:13230:13846:14096:14181:14721:14849:21080:21324:21451:21627:21939:21990:30012:30054:30064,0,RBL:198.145.29.99:@linux-foundation.org:.lbl8.mailshell.net-62.2.0.100 64.100.201.201;04y8h8jxm1pywk9kkn674roey1npnycnxenh3pbiw6qwo8qx8wrquep73brys3x.td8qdo8ptcmp45mpui14dt3rbrpqceufb5rkzbzrx5hobkptrdq89momn7adsi6.a-lbl8.mailshell.net-223.238.255.100,CacheIP:none,Bayesian:0.5,0.5,0.5,Netcheck:none,DomainCache:0,MSF:not bulk,SPF:fp,MSBL:0, DNSBL:ne X-HE-Tag: glue45_601108927229 X-Filterd-Recvd-Size: 3552 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by imf38.hostedemail.com (Postfix) with ESMTP for ; Sat, 17 Oct 2020 23:14:07 +0000 (UTC) Received: from localhost.localdomain (c-73-231-172-41.hsd1.ca.comcast.net [73.231.172.41]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id BE74E208E4; Sat, 17 Oct 2020 23:14:06 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1602976447; bh=0XHlP719nJRI+EVhTk6Cs4CWAHZk5C5nuGJnmRbAUzc=; h=Date:From:To:Subject:In-Reply-To:From; b=qxWpwbQ7s3Rx+Oj/Muw0KEc6BkAGTcTYZ9KHfbYn2OXtPiat+HMTdtNtqYd2xrchi m9vv+e3TspkL4JyynwycGUPXd0oNiTclqj6qGPXGKO+YTySUbyebM4QLW8jPArIU4L yljpKWaCnjpW+DLQYAS2n/jSjEoIr1+ZJsVNCIeQ= Date: Sat, 17 Oct 2020 16:14:06 -0700 From: Andrew Morton To: akpm@linux-foundation.org, Liam.Howlett@Oracle.com, linux-mm@kvack.org, mm-commits@vger.kernel.org, torvalds@linux-foundation.org Subject: [patch 10/40] mm/mmap: add inline vma_next() for readability of mmap code Message-ID: <20201017231406.Fm-sT8ouL%akpm@linux-foundation.org> In-Reply-To: <20201017161314.88890b87fae7446ccc13c902@linux-foundation.org> User-Agent: s-nail v14.8.16 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: From: "Liam R. Howlett" Subject: mm/mmap: add inline vma_next() for readability of mmap code 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. Link: http://lkml.kernel.org/r/20200818154707.2515169-1-Liam.Howlett@Oracle.com Signed-off-by: Liam R. Howlett Reviewed-by: Andrew Morton Signed-off-by: Andrew Morton --- mm/mmap.c | 26 ++++++++++++++++++++------ 1 file changed, 20 insertions(+), 6 deletions(-) --- a/mm/mmap.c~mm-mmap-add-inline-vma_next-for-readability-of-mmap-code +++ a/mm/mmap.c @@ -558,6 +558,23 @@ static int find_vma_links(struct mm_stru 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) { @@ -1128,10 +1145,7 @@ struct vm_area_struct *vma_merge(struct 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; @@ -2632,7 +2646,7 @@ static void unmap_region(struct mm_struc 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(); @@ -2831,7 +2845,7 @@ int __do_munmap(struct mm_struct *mm, un if (error) return error; } - vma = prev ? prev->vm_next : mm->mmap; + vma = vma_next(mm, prev); if (unlikely(uf)) { /*