From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1163462AbdEXLVB (ORCPT ); Wed, 24 May 2017 07:21:01 -0400 Received: from mx0a-001b2d01.pphosted.com ([148.163.156.1]:59484 "EHLO mx0a-001b2d01.pphosted.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1757719AbdEXLUQ (ORCPT ); Wed, 24 May 2017 07:20:16 -0400 From: Laurent Dufour To: linux-mm@kvack.org Cc: Davidlohr Bueso , akpm@linux-foundation.org, Jan Kara , "Kirill A . Shutemov" , Michal Hocko , Peter Zijlstra , Mel Gorman , Andi Kleen , haren@linux.vnet.ibm.com, aneesh.kumar@linux.vnet.ibm.com, khandual@linux.vnet.ibm.com, paulmck@linux.vnet.ibm.com, linux-kernel@vger.kernel.org Subject: [RFC v2 02/10] mm: Remove nest locking operation with mmap_sem Date: Wed, 24 May 2017 13:19:53 +0200 X-Mailer: git-send-email 2.7.4 In-Reply-To: <1495624801-8063-1-git-send-email-ldufour@linux.vnet.ibm.com> References: <1495624801-8063-1-git-send-email-ldufour@linux.vnet.ibm.com> X-TM-AS-GCONF: 00 x-cbid: 17052411-0008-0000-0000-000004532C66 X-IBM-AV-DETECTION: SAVI=unused REMOTE=unused XFE=unused x-cbparentid: 17052411-0009-0000-0000-00001DCE41CC Message-Id: <1495624801-8063-3-git-send-email-ldufour@linux.vnet.ibm.com> X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10432:,, definitions=2017-05-24_08:,, signatures=0 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 spamscore=0 suspectscore=1 malwarescore=0 phishscore=0 adultscore=0 bulkscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.0.1-1703280000 definitions=main-1705240054 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org The range locking framework doesn't yet provide nest locking operation. Once the range locking API while provide nested operation support, this patch will have to be reviewed. Signed-off-by: Laurent Dufour --- mm/mmap.c | 8 ++++++++ 1 file changed, 8 insertions(+) diff --git a/mm/mmap.c b/mm/mmap.c index f82741e199c0..87c8625ae91d 100644 --- a/mm/mmap.c +++ b/mm/mmap.c @@ -3284,7 +3284,11 @@ static void vm_lock_anon_vma(struct mm_struct *mm, struct anon_vma *anon_vma) * The LSB of head.next can't change from under us * because we hold the mm_all_locks_mutex. */ +#ifndef CONFIG_MEM_RANGE_LOCK down_write_nest_lock(&anon_vma->root->rwsem, &mm->mmap_sem); +#else + down_write(&anon_vma->root->rwsem); +#endif /* * We can safely modify head.next after taking the * anon_vma->root->rwsem. If some other vma in this mm shares @@ -3314,7 +3318,11 @@ static void vm_lock_mapping(struct mm_struct *mm, struct address_space *mapping) */ if (test_and_set_bit(AS_MM_ALL_LOCKS, &mapping->flags)) BUG(); +#ifndef CONFIG_MEM_RANGE_LOCK down_write_nest_lock(&mapping->i_mmap_rwsem, &mm->mmap_sem); +#else + down_write(&mapping->i_mmap_rwsem); +#endif } } -- 2.7.4