From mboxrd@z Thu Jan 1 00:00:00 1970 From: Wanpeng Li Subject: Re: [PATCH] mm/hugetlb_cgroup: Add list_del to remove unused page from hugepage_activelist when hugepage migration Date: Wed, 11 Jul 2012 17:17:14 +0800 Message-ID: <20120711091648.GA10841@kernel> References: <1341978718-6423-1-git-send-email-liwp.linux@gmail.com> <87wr2aitpk.fsf@skywalker.in.ibm.com> Reply-To: Wanpeng Li Mime-Version: 1.0 Return-path: DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20120113; h=date:from:to:cc:subject:message-id:reply-to:references:mime-version :content-type:content-disposition:in-reply-to:user-agent; bh=/WMhxa/qGO2KZJiU3Jq9GPMAxR82cVipc2Is9bfvbC8=; b=iySwFTU4C3450uE2tdsVF9pq6qP/IrCyKNgBKa/Lodoz5jvHuTeNge6cxW2TagQl+t HKyJeCgbQG30zNGwoACHtdhARA7mGwZKY7YstM8rdROtU8Cok3Eh/rKNDWO3m6Q4DxxT sirQJDdyHC9y5xIBA075NXA+51PPPSlnearm5mV4gQrDI4+omCg9EtrrFf6WktAS1fu3 q6RUhjWzzsb0DsUrI+JOfwZMI3k6gsCtrrafiEdXvlxEINs3p2FGYKN0I3yd5A4atK1g FicjkrODqLmrG6fOJhk83SlRS+YbeWtg1t+4bU3TDR4Tli6B6UavbPBDYpyb0M4bzcM6 07sg== Content-Disposition: inline In-Reply-To: <87wr2aitpk.fsf-6yE53ggjAfyqSkle7U1LjlaTQe2KTcn/@public.gmane.org> Sender: cgroups-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org List-ID: Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: "Aneesh Kumar K.V" Cc: Andrew Morton , Li Zefan , Tejun Heo , cgroups-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, Wanpeng Li 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