diff options
authorJiang Liu <jiang.liu@huawei.com>2013-03-19 12:36:58 +0100
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>2013-04-05 10:16:47 -0700
commitd9e61dba0c73294e9e6761f290dce2049f06bfac (patch)
parent16df76518569ae25da4c3750ad4bab65ef2aa900 (diff)
mm/hotplug: correctly add new zone to all other nodes' zone lists
commit 08dff7b7d629807dbb1f398c68dd9cd58dd657a1 upstream. When online_pages() is called to add new memory to an empty zone, it rebuilds all zone lists by calling build_all_zonelists(). But there's a bug which prevents the new zone to be added to other nodes' zone lists. online_pages() { build_all_zonelists() ..... node_set_state(zone_to_nid(zone), N_HIGH_MEMORY) } Here the node of the zone is put into N_HIGH_MEMORY state after calling build_all_zonelists(), but build_all_zonelists() only adds zones from nodes in N_HIGH_MEMORY state to the fallback zone lists. build_all_zonelists() ->__build_all_zonelists() ->build_zonelists() ->find_next_best_node() ->for_each_node_state(n, N_HIGH_MEMORY) So memory in the new zone will never be used by other nodes, and it may cause strange behavor when system is under memory pressure. So put node into N_HIGH_MEMORY state before calling build_all_zonelists(). Signed-off-by: Jianguo Wu <wujianguo@huawei.com> Signed-off-by: Jiang Liu <liuj97@gmail.com> Cc: Mel Gorman <mgorman@suse.de> Cc: Michal Hocko <mhocko@suse.cz> Cc: Minchan Kim <minchan@kernel.org> Cc: Rusty Russell <rusty@rustcorp.com.au> Cc: Yinghai Lu <yinghai@kernel.org> Cc: Tony Luck <tony.luck@intel.com> Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Cc: David Rientjes <rientjes@google.com> Cc: Keping Chen <chenkeping@huawei.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Jiri Slaby <jslaby@suse.cz> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
1 files changed, 8 insertions, 7 deletions
diff --git a/mm/memory_hotplug.c b/mm/memory_hotplug.c
index e0a3e51d5191..a739dd1de1a8 100644
--- a/mm/memory_hotplug.c
+++ b/mm/memory_hotplug.c
@@ -453,19 +453,20 @@ int __ref online_pages(unsigned long pfn, unsigned long nr_pages)
zone->present_pages += onlined_pages;
zone->zone_pgdat->node_present_pages += onlined_pages;
- if (need_zonelists_rebuild)
- build_all_zonelists(zone);
- else
- zone_pcp_update(zone);
+ if (onlined_pages) {
+ node_set_state(zone_to_nid(zone), N_HIGH_MEMORY);
+ if (need_zonelists_rebuild)
+ build_all_zonelists(zone);
+ else
+ zone_pcp_update(zone);
+ }
- if (onlined_pages) {
+ if (onlined_pages)
- node_set_state(zone_to_nid(zone), N_HIGH_MEMORY);
- }
vm_total_pages = nr_free_pagecache_pages();