From 09285af75d1682d8642607941ca6034ea1b159eb Mon Sep 17 00:00:00 2001 From: Lai Jiangshan Date: Wed, 12 Dec 2012 13:52:04 -0800 Subject: [PATCH] memory_hotplug: allow online/offline memory to result movable node Now, memory management can handle movable node or nodes which don't have any normal memory, so we can dynamic configure and add movable node by: online a ZONE_MOVABLE memory from a previous offline node offline the last normal memory which result a non-normal-memory-node movable-node is very important for power-saving, hardware partitioning and high-available-system(hardware fault management). Signed-off-by: Lai Jiangshan Tested-by: Yasuaki Ishimatsu Signed-off-by: Wen Congyang Cc: Jiang Liu Cc: KOSAKI Motohiro Cc: Minchan Kim Cc: Mel Gorman Cc: David Rientjes Cc: Yinghai Lu Cc: Rusty Russell Cc: Greg KH Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- mm/memory_hotplug.c | 16 ++++++++++++++++ 1 file changed, 16 insertions(+) diff --git a/mm/memory_hotplug.c b/mm/memory_hotplug.c index eca4aac1a83b..c6cd8b515424 100644 --- a/mm/memory_hotplug.c +++ b/mm/memory_hotplug.c @@ -581,11 +581,19 @@ static int online_pages_range(unsigned long start_pfn, unsigned long nr_pages, return 0; } +#ifdef CONFIG_MOVABLE_NODE +/* when CONFIG_MOVABLE_NODE, we allow online node don't have normal memory */ +static bool can_online_high_movable(struct zone *zone) +{ + return true; +} +#else /* #ifdef CONFIG_MOVABLE_NODE */ /* ensure every online node has NORMAL memory */ static bool can_online_high_movable(struct zone *zone) { return node_state(zone_to_nid(zone), N_NORMAL_MEMORY); } +#endif /* #ifdef CONFIG_MOVABLE_NODE */ /* check which state of node_states will be changed when online memory */ static void node_states_check_changes_online(unsigned long nr_pages, @@ -1093,6 +1101,13 @@ check_pages_isolated(unsigned long start_pfn, unsigned long end_pfn) return offlined; } +#ifdef CONFIG_MOVABLE_NODE +/* when CONFIG_MOVABLE_NODE, we allow online node don't have normal memory */ +static bool can_offline_normal(struct zone *zone, unsigned long nr_pages) +{ + return true; +} +#else /* #ifdef CONFIG_MOVABLE_NODE */ /* ensure the node has NORMAL memory if it is still online */ static bool can_offline_normal(struct zone *zone, unsigned long nr_pages) { @@ -1116,6 +1131,7 @@ static bool can_offline_normal(struct zone *zone, unsigned long nr_pages) */ return present_pages == 0; } +#endif /* #ifdef CONFIG_MOVABLE_NODE */ /* check which state of node_states will be changed when offline memory */ static void node_states_check_changes_offline(unsigned long nr_pages, -- 2.20.1