From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755605AbdCKCUW (ORCPT ); Fri, 10 Mar 2017 21:20:22 -0500 Received: from smtpbguseast2.qq.com ([54.204.34.130]:35213 "EHLO smtpbguseast2.qq.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755413AbdCKCUN (ORCPT ); Fri, 10 Mar 2017 21:20:13 -0500 X-QQ-mid: esmtp11t1489198803tckb2lxow X-QQ-SSF: 01000000000000506G100300000000V X-QQ-FEAT: QLRidG4u8QzbJoFi+HPN/U7NYhMkojaC3tkGbIW4YA3nKOYMvKMzCawlB0/Ev Lydr7KL/bxv5qrHX0dd6msrkCpqerTetDiCpKAdD09E7uFdQEWGxOXDQ3e76IpvY3U2i+wn wa73nEBsTRJpR1f9ykFlVEv2HI4I0f/QaNqe7FI/hFyR8nGKJUbaqc/+9lpHlmA2XJfr9xs RA9GT0q7TZLXPUxjfaje+ZggDPk91JUi8zcMY41PLIUhzqmG/OIEg63xVQtTwWQhpDzjpqF IB5w== X-QQ-GoodBg: 0 From: Yisheng Xie To: akpm@linux-foundation.org, hannes@cmpxchg.org, mgorman@suse.de, vbabka@suse.cz, mhocko@suse.com, riel@redhat.com Cc: linux-mm@kvack.org, linux-kernel@vger.kernel.org, xieyisheng1@huawei.com Subject: [PATCH RFC] mm/vmscan: donot retry shrink zones when memcg is disabled Date: Sat, 11 Mar 2017 10:19:58 +0800 Message-Id: <1489198798-6632-1-git-send-email-ysxie@foxmail.com> X-Mailer: git-send-email 1.9.1 X-QQ-SENDSIZE: 520 Feedback-ID: esmtp:foxmail.com:bgforeign:bgforeign3 X-QQ-Bgrelay: 1 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Yisheng Xie When we enter do_try_to_free_pages, the may_thrash is always clear, and it will retry shrink zones to tap cgroup's reserves memory by setting may_thrash when the former shrink_zones reclaim nothing. However, if CONFIG_MEMCG=n, it should not do this useless retry at all, for we do not have any cgroup's reserves memory to tap, and we have already done hard work and made no progress. Signed-off-by: Yisheng Xie --- mm/vmscan.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/mm/vmscan.c b/mm/vmscan.c index bc8031e..b03ccc1 100644 --- a/mm/vmscan.c +++ b/mm/vmscan.c @@ -2808,7 +2808,7 @@ static unsigned long do_try_to_free_pages(struct zonelist *zonelist, return 1; /* Untapped cgroup reserves? Don't OOM, retry. */ - if (!sc->may_thrash) { + if (!sc->may_thrash && IS_ENABLED(CONFIG_MEMCG)) { sc->priority = initial_priority; sc->may_thrash = 1; goto retry; -- 1.9.1