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=-15.2 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,NICE_REPLY_A,SPF_HELO_NONE,SPF_PASS,UNPARSEABLE_RELAY, URIBL_BLOCKED,USER_AGENT_SANE_1 autolearn=unavailable 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 E8B04C433FE for ; Sat, 12 Dec 2020 03:59:52 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 9DB8822D72 for ; Sat, 12 Dec 2020 03:59:52 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2438042AbgLLDxp (ORCPT ); Fri, 11 Dec 2020 22:53:45 -0500 Received: from out30-42.freemail.mail.aliyun.com ([115.124.30.42]:50688 "EHLO out30-42.freemail.mail.aliyun.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2405302AbgLLDxe (ORCPT ); Fri, 11 Dec 2020 22:53:34 -0500 X-Alimail-AntiSpam: AC=PASS;BC=-1|-1;BR=01201311R211e4;CH=green;DM=||false|;DS=||;FP=0|-1|-1|-1|0|-1|-1|-1;HT=alimailimapcm10staff010182156082;MF=alex.shi@linux.alibaba.com;NM=1;PH=DS;RN=3;SR=0;TI=SMTPD_---0UIIQwq4_1607745170; Received: from IT-FVFX43SYHV2H.lan(mailfrom:alex.shi@linux.alibaba.com fp:SMTPD_---0UIIQwq4_1607745170) by smtp.aliyun-inc.com(127.0.0.1); Sat, 12 Dec 2020 11:52:51 +0800 Subject: Re: [PATCH] mm/mmap: replace if (cond) BUG() with BUG_ON() From: Alex Shi Cc: Andrew Morton , linux-mm@kvack.org, linux-kernel@vger.kernel.org References: <1607743586-80303-1-git-send-email-alex.shi@linux.alibaba.com> <1607743586-80303-2-git-send-email-alex.shi@linux.alibaba.com> Message-ID: Date: Sat, 12 Dec 2020 11:52:50 +0800 User-Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10.0; rv:68.0) Gecko/20100101 Thunderbird/68.12.0 MIME-Version: 1.0 In-Reply-To: <1607743586-80303-2-git-send-email-alex.shi@linux.alibaba.com> Content-Type: text/plain; charset=gbk Content-Transfer-Encoding: 7bit To: unlisted-recipients:; (no To-header on input) Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org I'm very sorry, a typo here. the patch should be updated: >From ed4fa1c6d5bed5766c5f0c35af0c597855d7be06 Mon Sep 17 00:00:00 2001 From: Alex Shi Date: Fri, 11 Dec 2020 21:26:46 +0800 Subject: [PATCH] mm/mmap: replace if (cond) BUG() with BUG_ON() coccinelle reports some warnings: WARNING: Use BUG_ON instead of if condition followed by BUG. It could be fixed by BUG_ON(). Reported-by: abaci@linux.alibaba.com Signed-off-by: Alex Shi Cc: Andrew Morton Cc: linux-mm@kvack.org Cc: linux-kernel@vger.kernel.org --- mm/mmap.c | 22 ++++++++-------------- 1 file changed, 8 insertions(+), 14 deletions(-) diff --git a/mm/mmap.c b/mm/mmap.c index 8144fc3c5a78..107fa91bb59f 100644 --- a/mm/mmap.c +++ b/mm/mmap.c @@ -712,9 +712,8 @@ static void __insert_vm_struct(struct mm_struct *mm, struct vm_area_struct *vma) struct vm_area_struct *prev; struct rb_node **rb_link, *rb_parent; - if (find_vma_links(mm, vma->vm_start, vma->vm_end, - &prev, &rb_link, &rb_parent)) - BUG(); + BUG_ON(find_vma_links(mm, vma->vm_start, vma->vm_end, + &prev, &rb_link, &rb_parent)); __vma_link(mm, vma, prev, rb_link, rb_parent); mm->map_count++; } @@ -3585,9 +3584,8 @@ static void vm_lock_anon_vma(struct mm_struct *mm, struct anon_vma *anon_vma) * can't change from under us thanks to the * anon_vma->root->rwsem. */ - if (__test_and_set_bit(0, (unsigned long *) - &anon_vma->root->rb_root.rb_root.rb_node)) - BUG(); + BUG_ON(__test_and_set_bit(0, (unsigned long *) + &anon_vma->root->rb_root.rb_root.rb_node)); } } @@ -3603,8 +3601,7 @@ static void vm_lock_mapping(struct mm_struct *mm, struct address_space *mapping) * mm_all_locks_mutex, there may be other cpus * changing other bitflags in parallel to us. */ - if (test_and_set_bit(AS_MM_ALL_LOCKS, &mapping->flags)) - BUG(); + BUG_ON(test_and_set_bit(AS_MM_ALL_LOCKS, &mapping->flags)); down_write_nest_lock(&mapping->i_mmap_rwsem, &mm->mmap_lock); } } @@ -3701,9 +3698,8 @@ static void vm_unlock_anon_vma(struct anon_vma *anon_vma) * can't change from under us until we release the * anon_vma->root->rwsem. */ - if (!__test_and_clear_bit(0, (unsigned long *) - &anon_vma->root->rb_root.rb_root.rb_node)) - BUG(); + BUG_ON(!__test_and_clear_bit(0, (unsigned long *) + &anon_vma->root->rb_root.rb_root.rb_node)); anon_vma_unlock_write(anon_vma); } } @@ -3716,9 +3712,7 @@ static void vm_unlock_mapping(struct address_space *mapping) * because we hold the mm_all_locks_mutex. */ i_mmap_unlock_write(mapping); - if (!test_and_clear_bit(AS_MM_ALL_LOCKS, - &mapping->flags)) - BUG(); + BUG_ON(!test_and_clear_bit(AS_MM_ALL_LOCKS, &mapping->flags)); } } -- 2.29.GIT