From: Lai Jiangshan <laijs@xxxxxxxxxxxxxx> 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 <laijs@xxxxxxxxxxxxxx> --- mm/memory_hotplug.c | 16 ++++++++++++++++ 1 file changed, 16 insertions(+) diff --git a/mm/memory_hotplug.c b/mm/memory_hotplug.c index d07c66f..4aceb03 100644 --- a/mm/memory_hotplug.c +++ b/mm/memory_hotplug.c @@ -589,11 +589,19 @@ 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, @@ -1097,6 +1105,13 @@ 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) { @@ -1120,6 +1135,7 @@ 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, -- 1.8.0 -- 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