From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-lf1-f69.google.com (mail-lf1-f69.google.com [209.85.167.69]) by kanga.kvack.org (Postfix) with ESMTP id B9A2A6B0006 for ; Thu, 1 Nov 2018 13:37:56 -0400 (EDT) Received: by mail-lf1-f69.google.com with SMTP id h69so2620565lfg.10 for ; Thu, 01 Nov 2018 10:37:56 -0700 (PDT) Received: from forwardcorp1j.cmail.yandex.net (forwardcorp1j.cmail.yandex.net. [5.255.227.105]) by mx.google.com with ESMTPS id i140-v6si26316206lfg.118.2018.11.01.10.37.54 for (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Thu, 01 Nov 2018 10:37:54 -0700 (PDT) Subject: [PATCH RFC] mm: do not start node_reclaim for page order > MAX_ORDER From: Konstantin Khlebnikov Date: Thu, 01 Nov 2018 20:37:52 +0300 Message-ID: <154109387197.925352.10499549042420271600.stgit@buzz> MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit Sender: owner-linux-mm@kvack.org List-ID: To: linux-mm@kvack.org, Andrew Morton , Michal Hocko , linux-kernel@vger.kernel.org Page allocator has check in __alloc_pages_slowpath() but nowdays there is earlier entry point into reclimer without such check: get_page_from_freelist() -> node_reclaim(). Signed-off-by: Konstantin Khlebnikov --- mm/vmscan.c | 6 ++++++ 1 file changed, 6 insertions(+) diff --git a/mm/vmscan.c b/mm/vmscan.c index 62ac0c488624..52f672420f0b 100644 --- a/mm/vmscan.c +++ b/mm/vmscan.c @@ -4117,6 +4117,12 @@ int node_reclaim(struct pglist_data *pgdat, gfp_t gfp_mask, unsigned int order) { int ret; + /* + * Do not scan if allocation will never succeed. + */ + if (order >= MAX_ORDER) + return NODE_RECLAIM_NOSCAN; + /* * Node reclaim reclaims unmapped file backed pages and * slab pages if we are over the defined limits.