SLUB only fucus on the nodes which has normal memory, so ignore the other node's hot-adding and hot-removing. Aka: if some memroy of a node(which has no onlined memory) is online, but this new memory onlined is not normal memory(HIGH memory example), we should not allocate kmem_cache_node for SLUB. And if the last normal memory is offlined, but the node still has memroy, we should remove kmem_cache_node for that node.(current code delay it when all of the memory is offlined) so we only do something when marg->status_change_nid_normal > 0. marg->status_change_nid is not suitable here. The same problem doesn't exsit in SLAB, because SLAB allocates kmem_list3 for every node even the node don't have normal memory, SLAB tolerates kmem_list3 on alien nodes. SLUB only fucus on the nodes which has normal memory, it don't tolerates alien kmem_cache_node, the patch makes SLUB become self-compatible and avoid WARN and BUG in a rare condition. CC: David Rientjes <rientjes@xxxxxxxxxx> Cc: Minchan Kim <minchan.kim@xxxxxxxxx> CC: KOSAKI Motohiro <kosaki.motohiro@xxxxxxxxxxxxxx> CC: Yasuaki Ishimatsu <isimatu.yasuaki@xxxxxxxxxxxxxx> CC: Rob Landley <rob@xxxxxxxxxxx> CC: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> CC: Jiang Liu <jiang.liu@xxxxxxxxxx> CC: Kay Sievers <kay.sievers@xxxxxxxx> CC: Greg Kroah-Hartman <gregkh@xxxxxxx> CC: Mel Gorman <mgorman@xxxxxxx> CC: 'FNST-Wen Congyang' <wency@xxxxxxxxxxxxxx> CC: linux-doc@xxxxxxxxxxxxxxx CC: linux-kernel@xxxxxxxxxxxxxxx CC: linux-mm@xxxxxxxxx Signed-off-by: Lai Jiangshan <laijs@xxxxxxxxxxxxxx> --- mm/slub.c | 4 ++-- 1 files changed, 2 insertions(+), 2 deletions(-) diff --git a/mm/slub.c b/mm/slub.c index a0d6984..487f0bd 100644 --- a/mm/slub.c +++ b/mm/slub.c @@ -3573,7 +3573,7 @@ static void slab_mem_offline_callback(void *arg) struct memory_notify *marg = arg; int offline_node; - offline_node = marg->status_change_nid; + offline_node = marg->status_change_nid_normal; /* * If the node still has available memory. we need kmem_cache_node @@ -3606,7 +3606,7 @@ static int slab_mem_going_online_callback(void *arg) struct kmem_cache_node *n; struct kmem_cache *s; struct memory_notify *marg = arg; - int nid = marg->status_change_nid; + int nid = marg->status_change_nid_normal; int ret = 0; /* -- 1.7.4.4 -- To unsubscribe from this list: send the line "unsubscribe linux-doc" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
