[PATCH v3 4/5] powerpc/mm: restore top-down allocation when using movable_node

[Reza Arbab]

At boot, the movable_node option sets bottom-up memblock allocation.

This reduces the chance that, in the window before movable memory has
been identified, an allocation for the kernel might come from a movable
node. By going bottom-up, early allocations will most likely come from
the same node as the kernel image, which is necessarily in a nonmovable
node.

Then, once any known hotplug memory has been marked, allocation can be
reset back to top-down. On x86, this is done in numa_init(). This patch
does the same on power, in numa initmem_init().

Signed-off-by: Reza Arbab <arbab@xxxxxxxxxxxxxxxxxx>
---
 arch/powerpc/mm/numa.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/arch/powerpc/mm/numa.c b/arch/powerpc/mm/numa.c
index d7ac419..fdf1e69 100644
--- a/arch/powerpc/mm/numa.c
+++ b/arch/powerpc/mm/numa.c
@@ -945,6 +945,9 @@ void __init initmem_init(void)
 	max_low_pfn = memblock_end_of_DRAM() >> PAGE_SHIFT;
 	max_pfn = max_low_pfn;
 
+	/* bottom-up allocation may have been set by movable_node */
+	memblock_set_bottom_up(false);
+
 	if (parse_numa_properties())
 		setup_nonnuma();
 	else
-- 
1.8.3.1