[POWERPC] Don't use SLAB/SLUB for PTE pages

The SLUB allocator relies on struct page fields first_page and slab,
overwritten by ptl when SPLIT_PTLOCK: so the SLUB allocator cannot then
be used for the lowest level of pagetable pages.  This was obstructing
SLUB on PowerPC, which uses kmem_caches for its pagetables.  So convert
its pte level to use normal gfp pages (whereas pmd, pud and 64k-page pgd
want partpages, so continue to use kmem_caches for pmd, pud and pgd).

Signed-off-by: Hugh Dickins <hugh@veritas.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>

1 files changed, 0 insertions, 13 deletions

diff --git a/arch/powerpc/Kconfig b/arch/powerpc/Kconfig
index ecd459dd1baf..ccc5410af996 100644
--- a/arch/powerpc/Kconfig
+++ b/arch/powerpc/Kconfig
@@ -120,19 +120,6 @@ config GENERIC_BUG
 config SYS_SUPPORTS_APM_EMULATION
         bool
 
-#
-# Powerpc uses the slab allocator to manage its ptes and the
-# page structs of ptes are used for splitting the page table
-# lock for configurations supporting more than SPLIT_PTLOCK_CPUS.
-#
-# In that special configuration the page structs of slabs are modified.
-# This setting disables the selection of SLUB as a slab allocator.
-#
-config ARCH_USES_SLAB_PAGE_STRUCT
-        bool
-        default y
-        depends on SPLIT_PTLOCK_CPUS <= NR_CPUS
-
 config DEFAULT_UIMAGE
         bool
         help