From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752839AbeBFSUM (ORCPT ); Tue, 6 Feb 2018 13:20:12 -0500 Received: from userp2120.oracle.com ([156.151.31.85]:50304 "EHLO userp2120.oracle.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752702AbeBFSUE (ORCPT ); Tue, 6 Feb 2018 13:20:04 -0500 Subject: Re: [RFC PATCH v1 13/13] mm: splice local lists onto the front of the LRU To: Laurent Dufour , linux-mm@kvack.org, linux-kernel@vger.kernel.org Cc: aaron.lu@intel.com, ak@linux.intel.com, akpm@linux-foundation.org, Dave.Dice@oracle.com, dave@stgolabs.net, khandual@linux.vnet.ibm.com, mgorman@suse.de, mhocko@kernel.org, pasha.tatashin@oracle.com, steven.sistare@oracle.com, yossi.lev@oracle.com References: <20180131230413.27653-1-daniel.m.jordan@oracle.com> <20180131230413.27653-14-daniel.m.jordan@oracle.com> <765238a2-8970-e05d-4fe3-cdcb796aa399@linux.vnet.ibm.com> From: Daniel Jordan Organization: Oracle Corporation Message-ID: Date: Tue, 6 Feb 2018 13:18:53 -0500 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:52.0) Gecko/20100101 Thunderbird/52.6.0 MIME-Version: 1.0 In-Reply-To: <765238a2-8970-e05d-4fe3-cdcb796aa399@linux.vnet.ibm.com> Content-Type: text/plain; charset=utf-8; format=flowed Content-Language: en-US Content-Transfer-Encoding: 7bit X-Proofpoint-Virus-Version: vendor=nai engine=5900 definitions=8796 signatures=668662 X-Proofpoint-Spam-Details: rule=notspam policy=default score=0 suspectscore=0 malwarescore=0 phishscore=0 bulkscore=0 spamscore=0 mlxscore=0 mlxlogscore=999 adultscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.0.1-1711220000 definitions=main-1802060231 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 02/02/2018 10:22 AM, Laurent Dufour wrote: > On 01/02/2018 00:04, daniel.m.jordan@oracle.com wrote: ...snip... >> diff --git a/mm/memcontrol.c b/mm/memcontrol.c >> index 99a54df760e3..6911626f29b2 100644 >> --- a/mm/memcontrol.c >> +++ b/mm/memcontrol.c >> @@ -2077,6 +2077,7 @@ static void lock_page_lru(struct page *page, int *isolated) >> >> lruvec = mem_cgroup_page_lruvec(page, zone->zone_pgdat); >> ClearPageLRU(page); >> + smp_rmb(); /* Pairs with smp_wmb in __pagevec_lru_add */ > > Why not include the call to smp_rmb() in del_page_from_lru_list() instead > of spreading smp_rmb() before calls to del_page_from_lru_list() ? Yes, this is what I should have done. The memory barriers came from another patch I squashed in and I didn't look back to see how obvious the encapsulation was.