From fd8cfd3000191cb7f5b9ea8640bd46181f6b4b74 Mon Sep 17 00:00:00 2001 From: Hugh Dickins Date: Thu, 19 May 2016 17:13:00 -0700 Subject: arch: fix has_transparent_hugepage() I've just discovered that the useful-sounding has_transparent_hugepage() is actually an architecture-dependent minefield: on some arches it only builds if CONFIG_TRANSPARENT_HUGEPAGE=y, on others it's also there when not, but on some of those (arm and arm64) it then gives the wrong answer; and on mips alone it's marked __init, which would crash if called later (but so far it has not been called later). Straighten this out: make it available to all configs, with a sensible default in asm-generic/pgtable.h, removing its definitions from those arches (arc, arm, arm64, sparc, tile) which are served by the default, adding #define has_transparent_hugepage has_transparent_hugepage to those (mips, powerpc, s390, x86) which need to override the default at runtime, and removing the __init from mips (but maybe that kind of code should be avoided after init: set a static variable the first time it's called). Signed-off-by: Hugh Dickins Cc: "Kirill A. Shutemov" Cc: Andrea Arcangeli Cc: Andres Lagar-Cavilla Cc: Yang Shi Cc: Ning Qu Cc: Mel Gorman Cc: Konstantin Khlebnikov Acked-by: David S. Miller Acked-by: Vineet Gupta [arch/arc] Acked-by: Gerald Schaefer [arch/s390] Acked-by: Ingo Molnar Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- arch/s390/include/asm/pgtable.h | 1 + 1 file changed, 1 insertion(+) (limited to 'arch/s390') diff --git a/arch/s390/include/asm/pgtable.h b/arch/s390/include/asm/pgtable.h index 2f66645587a2..18d2beb89340 100644 --- a/arch/s390/include/asm/pgtable.h +++ b/arch/s390/include/asm/pgtable.h @@ -1223,6 +1223,7 @@ static inline int pmd_trans_huge(pmd_t pmd) return pmd_val(pmd) & _SEGMENT_ENTRY_LARGE; } +#define has_transparent_hugepage has_transparent_hugepage static inline int has_transparent_hugepage(void) { return MACHINE_HAS_HPAGE ? 1 : 0; -- cgit v1.2.3