From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754641Ab2GKJRq (ORCPT ); Wed, 11 Jul 2012 05:17:46 -0400 Received: from mail-pb0-f46.google.com ([209.85.160.46]:50509 "EHLO mail-pb0-f46.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751835Ab2GKJRo (ORCPT ); Wed, 11 Jul 2012 05:17:44 -0400 Date: Wed, 11 Jul 2012 17:17:14 +0800 From: Wanpeng Li To: "Aneesh Kumar K.V" Cc: Andrew Morton , Li Zefan , Tejun Heo , cgroups@vger.kernel.org, linux-kernel@vger.kernel.org, Wanpeng Li Subject: Re: [PATCH] mm/hugetlb_cgroup: Add list_del to remove unused page from hugepage_activelist when hugepage migration Message-ID: <20120711091648.GA10841@kernel> Reply-To: Wanpeng Li References: <1341978718-6423-1-git-send-email-liwp.linux@gmail.com> <87wr2aitpk.fsf@skywalker.in.ibm.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <87wr2aitpk.fsf@skywalker.in.ibm.com> User-Agent: Mutt/1.5.21 (2010-09-15) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, Jul 11, 2012 at 02:02:23PM +0530, Aneesh Kumar K.V wrote: >Wanpeng Li writes: > >> From: Wanpeng Li >> >> hugepage_activelist is used to track currently used HugeTLB pages. >> We can find the in-use HugeTLB pages to support HugeTLB cgroup >> removal. Don't keep unused page in hugetlb_activelist too long. >> Otherwise, on cgroup removal we should update the unused page's >> charge to parent count. To reduce this overhead, remove unused page >> from hugepage_activelist immediately. >> >> Signed-off-by: Wanpeng Li >> --- >> mm/hugetlb_cgroup.c | 1 + >> 1 files changed, 1 insertions(+), 0 deletions(-) >> >> diff --git a/mm/hugetlb_cgroup.c b/mm/hugetlb_cgroup.c >> index b834e8d..d819d66 100644 >> --- a/mm/hugetlb_cgroup.c >> +++ b/mm/hugetlb_cgroup.c >> @@ -398,6 +398,7 @@ void hugetlb_cgroup_migrate(struct page *oldhpage, struct page *newhpage) >> spin_lock(&hugetlb_lock); >> h_cg = hugetlb_cgroup_from_page(oldhpage); >> set_hugetlb_cgroup(oldhpage, NULL); >> + list_del(&oldhpage->lru); >> >> /* move the h_cg details to new cgroup */ >> set_hugetlb_cgroup(newhpage, h_cg); > >put_page on the oldhpage will do that. If we do list_del here >free_huge_page() will have error list_move(). I don't know if move the page to other lists when migration in order to reduce overhead I mentioned make sense. :-) Regards, Wanpeng Li > >-aneesh