From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1034538AbdEYGsv (ORCPT ); Thu, 25 May 2017 02:48:51 -0400 Received: from mga06.intel.com ([134.134.136.31]:36317 "EHLO mga06.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1165235AbdEYGrJ (ORCPT ); Thu, 25 May 2017 02:47:09 -0400 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.38,390,1491289200"; d="scan'208";a="972848791" From: "Huang, Ying" To: Andrew Morton Cc: linux-mm@kvack.org, linux-kernel@vger.kernel.org, Huang Ying , Johannes Weiner , Minchan Kim , Michal Hocko , Andrea Arcangeli , "Kirill A . Shutemov" Subject: [PATCH -mm 09/13] memcg, THP, swap: Support move mem cgroup charge for THP swapped out Date: Thu, 25 May 2017 14:46:31 +0800 Message-Id: <20170525064635.2832-10-ying.huang@intel.com> X-Mailer: git-send-email 2.11.0 In-Reply-To: <20170525064635.2832-1-ying.huang@intel.com> References: <20170525064635.2832-1-ying.huang@intel.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Huang Ying PTE mapped THP (Transparent Huge Page) will be ignored when moving memory cgroup charge. But for THP which is in the swap cache, the memory cgroup charge for the swap of a tail-page may be moved in current implementation. That isn't correct, because the swap charge for all sub-pages of a THP should be moved together. Following the processing of the PTE mapped THP, the mem cgroup charge moving for the swap entry for a tail-page of a THP is ignored too. Signed-off-by: "Huang, Ying" Cc: Johannes Weiner Cc: Minchan Kim Cc: Michal Hocko Cc: Andrea Arcangeli Cc: "Kirill A . Shutemov" --- mm/memcontrol.c | 7 +++++-- 1 file changed, 5 insertions(+), 2 deletions(-) diff --git a/mm/memcontrol.c b/mm/memcontrol.c index c131f7e5ecd1..1f36bb61a6de 100644 --- a/mm/memcontrol.c +++ b/mm/memcontrol.c @@ -4606,8 +4606,11 @@ static enum mc_target_type get_mctgt_type(struct vm_area_struct *vma, if (!ret || !target) put_page(page); } - /* There is a swap entry and a page doesn't exist or isn't charged */ - if (ent.val && !ret && + /* + * There is a swap entry and a page doesn't exist or isn't charged. + * But we cannot move a tail-page in a THP. + */ + if (ent.val && !ret && (!page || !PageTransCompound(page)) && mem_cgroup_id(mc.from) == lookup_swap_cgroup_id(ent)) { ret = MC_TARGET_SWAP; if (target) -- 2.11.0