Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751231AbdFDUBt (ORCPT ); Sun, 4 Jun 2017 16:01:49 -0400 Received: from mail-pf0-f182.google.com ([209.85.192.182]:33272 "EHLO mail-pf0-f182.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751180AbdFDUBm (ORCPT ); Sun, 4 Jun 2017 16:01:42 -0400 From: Yu Zhao To: Johannes Weiner , Michal Hocko , Vladimir Davydov Cc: cgroups@vger.kernel.org, linux-mm@kvack.org, linux-kernel@vger.kernel.org, Yu Zhao Subject: [PATCH v2] swap: cond_resched in swap_cgroup_prepare() Date: Sun, 4 Jun 2017 13:01:09 -0700 Message-Id: <20170604200109.17606-1-yuzhao@google.com> X-Mailer: git-send-email 2.13.0.506.g27d5fe0cd-goog In-Reply-To: <20170601195635.20744-1-yuzhao@google.com> References: <20170601195635.20744-1-yuzhao@google.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 902 Lines: 33 Saw need_resched() warnings when swapping on large swapfile (TBs) because continuously allocating many pages in swap_cgroup_prepare() took too long. We already cond_resched when freeing page in swap_cgroup_swapoff(). Do the same for the page allocation. Signed-off-by: Yu Zhao Acked-by: Michal Hocko Acked-by: Vladimir Davydov --- Changelog since v1: * clarify the problem in the commit message mm/swap_cgroup.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/mm/swap_cgroup.c b/mm/swap_cgroup.c index ac6318a064d3..3405b4ee1757 100644 --- a/mm/swap_cgroup.c +++ b/mm/swap_cgroup.c @@ -48,6 +48,9 @@ static int swap_cgroup_prepare(int type) if (!page) goto not_enough_page; ctrl->map[idx] = page; + + if (!(idx % SWAP_CLUSTER_MAX)) + cond_resched(); } return 0; not_enough_page: -- 2.13.0.506.g27d5fe0cd-goog