[SPARC64]: Use SPARSEMEM_STATIC

Decrease the SECTION_SIZE_BITS --> MAX_PHYSADDR_BITS
range a little bit.

The cost of going to SPARSEMEM_STATIC becomes 8K of BSS space, and in
return we save a pointer dereferences on every page struct lookup.
Even better we hit the main kernel image for the base address which is
in a hugepage locked TLB entry.

Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/arch/sparc64/Kconfig b/arch/sparc64/Kconfig
index 51c87fdd998c3a1de4038ada10d9200f4ef15d96..590a41b864b9227cfda9bf4dbe24daceeede71b7 100644 (file)
--- a/arch/sparc64/Kconfig
+++ b/arch/sparc64/Kconfig
@@ -220,6 +220,7 @@ config ARCH_SPARSEMEM_ENABLE
 
 config ARCH_SPARSEMEM_DEFAULT
        def_bool y
+       select SPARSEMEM_STATIC
 
 config LARGE_ALLOCS
        def_bool y

diff --git a/include/asm-sparc64/sparsemem.h b/include/asm-sparc64/sparsemem.h
index ed5c9d8541e226f8fc5a8d79790e05d5a5360b26..411e0e255cf30778fd4ebf6843d8082b3867a0df 100644 (file)
--- a/include/asm-sparc64/sparsemem.h
+++ b/include/asm-sparc64/sparsemem.h
@@ -3,9 +3,9 @@
 
 #ifdef __KERNEL__
 
-#define SECTION_SIZE_BITS       26
-#define MAX_PHYSADDR_BITS       42
-#define MAX_PHYSMEM_BITS        42
+#define SECTION_SIZE_BITS       31
+#define MAX_PHYSADDR_BITS       41
+#define MAX_PHYSMEM_BITS        41
 
 #endif /* !(__KERNEL__) */