From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-qt0-f200.google.com (mail-qt0-f200.google.com [209.85.216.200]) by kanga.kvack.org (Postfix) with ESMTP id 64A616B0253 for ; Tue, 24 Jan 2017 02:49:18 -0500 (EST) Received: by mail-qt0-f200.google.com with SMTP id t56so141269588qte.3 for ; Mon, 23 Jan 2017 23:49:18 -0800 (PST) Received: from mail-qt0-x244.google.com (mail-qt0-x244.google.com. [2607:f8b0:400d:c0d::244]) by mx.google.com with ESMTPS id o37si12610407qtf.38.2017.01.23.23.49.17 for (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Mon, 23 Jan 2017 23:49:17 -0800 (PST) Received: by mail-qt0-x244.google.com with SMTP id f4so23189655qte.2 for ; Mon, 23 Jan 2017 23:49:17 -0800 (PST) From: Jia He Subject: [PATCH RFC 1/3] mm/hugetlb: split alloc_fresh_huge_page_node into fast and slow path Date: Tue, 24 Jan 2017 15:49:02 +0800 Message-Id: <1485244144-13487-2-git-send-email-hejianet@gmail.com> In-Reply-To: <1485244144-13487-1-git-send-email-hejianet@gmail.com> References: <1485244144-13487-1-git-send-email-hejianet@gmail.com> Sender: owner-linux-mm@kvack.org List-ID: To: linux-mm@kvack.org, linux-kernel@vger.kernel.org Cc: Andrew Morton , Naoya Horiguchi , Michal Hocko , Mike Kravetz , "Aneesh Kumar K.V" , Gerald Schaefer , zhong jiang , "Kirill A. Shutemov" , Vaishali Thakkar , Johannes Weiner , Mel Gorman , Vlastimil Babka , Minchan Kim , Rik van Riel , Jia He This patch split alloc_fresh_huge_page_node into 2 parts: - fast path without __GFP_REPEAT flag - slow path with __GFP_REPEAT flag Thus, if there is a server with uneven numa memory layout: available: 7 nodes (0-6) node 0 cpus: 0 1 2 3 4 5 6 7 node 0 size: 6603 MB node 0 free: 91 MB node 1 cpus: node 1 size: 12527 MB node 1 free: 157 MB node 2 cpus: node 2 size: 15087 MB node 2 free: 189 MB node 3 cpus: node 3 size: 16111 MB node 3 free: 205 MB node 4 cpus: 8 9 10 11 12 13 14 15 node 4 size: 24815 MB node 4 free: 310 MB node 5 cpus: node 5 size: 4095 MB node 5 free: 61 MB node 6 cpus: node 6 size: 22750 MB node 6 free: 283 MB node distances: node 0 1 2 3 4 5 6 0: 10 20 40 40 40 40 40 1: 20 10 40 40 40 40 40 2: 40 40 10 20 40 40 40 3: 40 40 20 10 40 40 40 4: 40 40 40 40 10 20 40 5: 40 40 40 40 20 10 40 6: 40 40 40 40 40 40 10 In this case node 5 has less memory and we will alloc the hugepages from these nodes one by one. After this patch, we will not trigger too early direct memory/kswap reclaim for node 5 if there are enough memory in other nodes. Signed-off-by: Jia He --- mm/hugetlb.c | 9 +++++++++ 1 file changed, 9 insertions(+) diff --git a/mm/hugetlb.c b/mm/hugetlb.c index c7025c1..f2415ce 100644 --- a/mm/hugetlb.c +++ b/mm/hugetlb.c @@ -1364,10 +1364,19 @@ static struct page *alloc_fresh_huge_page_node(struct hstate *h, int nid) { struct page *page; + /* fast path without __GFP_REPEAT */ page = __alloc_pages_node(nid, htlb_alloc_mask(h)|__GFP_COMP|__GFP_THISNODE| __GFP_REPEAT|__GFP_NOWARN, huge_page_order(h)); + + /* slow path with __GFP_REPEAT*/ + if (!page) + page = __alloc_pages_node(nid, + htlb_alloc_mask(h)|__GFP_COMP|__GFP_THISNODE| + __GFP_NOWARN, + huge_page_order(h)); + if (page) { prep_new_huge_page(h, page, nid); } -- 2.5.5 -- 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