From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-io0-f197.google.com (mail-io0-f197.google.com [209.85.223.197]) by kanga.kvack.org (Postfix) with ESMTP id 0B38F6B0038 for ; Tue, 20 Sep 2016 02:57:37 -0400 (EDT) Received: by mail-io0-f197.google.com with SMTP id 92so31358366iom.2 for ; Mon, 19 Sep 2016 23:57:37 -0700 (PDT) Received: from szxga01-in.huawei.com (szxga01-in.huawei.com. [58.251.152.64]) by mx.google.com with ESMTPS id v88si33297389iov.139.2016.09.19.23.57.35 for (version=TLS1 cipher=AES128-SHA bits=128/128); Mon, 19 Sep 2016 23:57:36 -0700 (PDT) From: zhongjiang Subject: [PATCH] mm,ksm: add __GFP_HIGH to the allocation in alloc_stable_node() Date: Tue, 20 Sep 2016 14:54:44 +0800 Message-ID: <1474354484-58233-1-git-send-email-zhongjiang@huawei.com> MIME-Version: 1.0 Content-Type: text/plain Sender: owner-linux-mm@kvack.org List-ID: To: hughd@google.com, akpm@linux-foundation.org, mhocko@suse.cz, vbabka@suse.cz, rientjes@google.com Cc: linux-mm@kvack.org From: zhong jiang Accoding to HUgh's suggestion, alloc_stable_node() with GFP_KERNEL will cause the hungtask, despite less possiblity. At present, if alloc_stable_node allocate fails, two break_cow may want to allocate a couple of pages, and the issue will come up when free memory is under pressure. we fix it by adding the __GFP_HIGH to GFP. because it grant access to some of meory reserves. it will make progess to make it allocation successful at the utmost. Suggested-by: Hugh Dickins Signed-off-by: zhong jiang --- mm/ksm.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/mm/ksm.c b/mm/ksm.c index 5048083..42bf16e 100644 --- a/mm/ksm.c +++ b/mm/ksm.c @@ -299,7 +299,7 @@ static inline void free_rmap_item(struct rmap_item *rmap_item) static inline struct stable_node *alloc_stable_node(void) { - return kmem_cache_alloc(stable_node_cache, GFP_KERNEL); + return kmem_cache_alloc(stable_node_cache, GFP_KERNEL | __GFP_HIGH); } static inline void free_stable_node(struct stable_node *stable_node) -- 1.8.3.1 -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: email@kvack.org