From 231e97e2b8ec9a1556ced5d8a89cda03a480b179 Mon Sep 17 00:00:00 2001 From: Li Zhong Date: Wed, 28 Sep 2016 15:22:38 -0700 Subject: [PATCH] mem-hotplug: use nodes that contain memory as mask in new_node_page() 9bb627be47a5 ("mem-hotplug: don't clear the only node in new_node_page()") prevents allocating from an empty nodemask, but as David points out, it is still wrong. As node_online_map may include memoryless nodes, only allocating from these nodes is meaningless. This patch uses node_states[N_MEMORY] mask to prevent the above case. Fixes: 9bb627be47a5 ("mem-hotplug: don't clear the only node in new_node_page()") Fixes: 394e31d2ceb4 ("mem-hotplug: alloc new page from a nearest neighbor node when mem-offline") Link: http://lkml.kernel.org/r/1474447117.28370.6.camel@TP420 Signed-off-by: Li Zhong Suggested-by: David Rientjes Acked-by: Vlastimil Babka Cc: Michal Hocko Cc: John Allen Cc: Xishi Qiu Cc: Joonsoo Kim Cc: Naoya Horiguchi Cc: Tetsuo Handa Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- mm/memory_hotplug.c | 10 +++++----- 1 file changed, 5 insertions(+), 5 deletions(-) diff --git a/mm/memory_hotplug.c b/mm/memory_hotplug.c index b58906b6215c..9d29ba0f7192 100644 --- a/mm/memory_hotplug.c +++ b/mm/memory_hotplug.c @@ -1555,8 +1555,8 @@ static struct page *new_node_page(struct page *page, unsigned long private, { gfp_t gfp_mask = GFP_USER | __GFP_MOVABLE; int nid = page_to_nid(page); - nodemask_t nmask = node_online_map; - struct page *new_page; + nodemask_t nmask = node_states[N_MEMORY]; + struct page *new_page = NULL; /* * TODO: allocate a destination hugepage from a nearest neighbor node, @@ -1567,14 +1567,14 @@ static struct page *new_node_page(struct page *page, unsigned long private, return alloc_huge_page_node(page_hstate(compound_head(page)), next_node_in(nid, nmask)); - if (nid != next_node_in(nid, nmask)) - node_clear(nid, nmask); + node_clear(nid, nmask); if (PageHighMem(page) || (zone_idx(page_zone(page)) == ZONE_MOVABLE)) gfp_mask |= __GFP_HIGHMEM; - new_page = __alloc_pages_nodemask(gfp_mask, 0, + if (!nodes_empty(nmask)) + new_page = __alloc_pages_nodemask(gfp_mask, 0, node_zonelist(nid, gfp_mask), &nmask); if (!new_page) new_page = __alloc_pages(gfp_mask, 0, -- 2.20.1