path: root/init
diff options
authorMel Gorman <>2014-10-09 15:26:33 -0700
committerLinus Torvalds <>2014-10-09 22:25:52 -0400
commit6a33979d5bd7521497121c5ae4435d7003115a0f (patch)
treef010f2441b1942f0153b999fa987196e68a30272 /init
parented2f240094f900833ac06f533ab8bbcf0a1e8199 (diff)
mm: remove misleading ARCH_USES_NUMA_PROT_NONE
ARCH_USES_NUMA_PROT_NONE was defined for architectures that implemented _PAGE_NUMA using _PROT_NONE. This saved using an additional PTE bit and relied on the fact that PROT_NONE vmas were skipped by the NUMA hinting fault scanner. This was found to be conceptually confusing with a lot of implicit assumptions and it was asked that an alternative be found. Commit c46a7c81 "x86: define _PAGE_NUMA by reusing software bits on the PMD and PTE levels" redefined _PAGE_NUMA on x86 to be one of the swap PTE bits and shrunk the maximum possible swap size but it did not go far enough. There are no architectures that reuse _PROT_NONE as _PROT_NUMA but the relics still exist. This patch removes ARCH_USES_NUMA_PROT_NONE and removes some unnecessary duplication in powerpc vs the generic implementation by defining the types the core NUMA helpers expected to exist from x86 with their ppc64 equivalent. This necessitated that a PTE bit mask be created that identified the bits that distinguish present from NUMA pte entries but it is expected this will only differ between arches based on _PAGE_PROTNONE. The naming for the generic helpers was taken from x86 originally but ppc64 has types that are equivalent for the purposes of the helper so they are mapped instead of duplicating code. Signed-off-by: Mel Gorman <> Cc: Hugh Dickins <> Cc: "Kirill A. Shutemov" <> Cc: Rik van Riel <> Cc: Johannes Weiner <> Cc: Cyrill Gorcunov <> Reviewed-by: Aneesh Kumar K.V <> Signed-off-by: Andrew Morton <> Signed-off-by: Linus Torvalds <>
Diffstat (limited to 'init')
1 files changed, 0 insertions, 11 deletions
diff --git a/init/Kconfig b/init/Kconfig
index e25a82a291a6..d2355812ba48 100644
--- a/init/Kconfig
+++ b/init/Kconfig
@@ -889,17 +889,6 @@ config ARCH_SUPPORTS_INT128
-# For architectures that are willing to define _PAGE_NUMA as _PAGE_PROTNONE
- bool
- bool
- default y
- depends on NUMA_BALANCING
bool "Automatically enable NUMA aware memory/task placement"
default y