We would want to use number of page table level to define mm_struct.
Let's expose it as CONFIG_PGTABLE_LEVELS.
Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: "David S. Miller" <davem@davemloft.net>
Tested-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
 config ARCH_SUPPORTS_DEBUG_PAGEALLOC
        def_bool y if SPARC64
 
+config PGTABLE_LEVELS
+       default 4 if 64BIT
+       default 3
+
 source "init/Kconfig"
 
 source "kernel/Kconfig.freezer"