mm: select HAVE_MOVE_PMD on x86 for faster mremap

Moving page-tables at the PMD-level on x86 is known to be safe.  Enable
this option so that we can do fast mremap when possible.

Link: http://lkml.kernel.org/r/[email protected]
Signed-off-by: Joel Fernandes (Google) <[email protected]>
Suggested-by: Kirill A. Shutemov <[email protected]>
Acked-by: Kirill A. Shutemov <[email protected]>
Cc: Julia Lawall <[email protected]>
Cc: Michal Hocko <[email protected]>
Cc: William Kucharski <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>

diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig
index e260460210e17a6009097542d15b8797e596b1d6..6185d4f332965e32b2229547c626269dd5bb9b16 100644 (file)
--- a/arch/x86/Kconfig
+++ b/arch/x86/Kconfig
@@ -172,6 +172,7 @@ config X86
        select HAVE_MEMBLOCK_NODE_MAP
        select HAVE_MIXED_BREAKPOINTS_REGS
        select HAVE_MOD_ARCH_SPECIFIC
+       select HAVE_MOVE_PMD
        select HAVE_NMI
        select HAVE_OPROFILE
        select HAVE_OPTPROBES