arm64: NUMA: Kconfig: Increase NODES_SHIFT to 4

The current arm64 default config limits max NUMA nodes available on
system to 4 (NODES_SHIFT = 2). Today's arm64 systems can reach or
exceed 16 NUMA nodes. To accomodate current hardware and to fit
NODES_SHIFT within page flags on arm64, increase NODES_SHIFT to 4.

Signed-off-by: Vanshidhar Konda <vanshikonda@os.amperecomputing.com>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Link: https://lore.kernel.org/r/20201020173409.1266576-1-vanshikonda@os.amperecomputing.com/
Link: https://lore.kernel.org/r/20201030173050.1182876-1-vanshikonda@os.amperecomputing.com
Signed-off-by: Will Deacon <will@kernel.org>

diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig
index 1d466ad..1515f6f 100644 (file)
--- a/arch/arm64/Kconfig
+++ b/arch/arm64/Kconfig
@@ -1002,7 +1002,7 @@ config NUMA
 config NODES_SHIFT
        int "Maximum NUMA Nodes (as a power of 2)"
        range 1 10
-       default "2"
+       default "4"
        depends on NEED_MULTIPLE_NODES
        help
          Specify the maximum number of NUMA Nodes available on the target