Commit 4d86d4f7 authored by Peter Collingbourne's avatar Peter Collingbourne Committed by Andrew Morton
Browse files

mm: add more BUILD_BUG_ONs to gfp_migratetype() 

gfp_migratetype() also expects GFP_RECLAIMABLE and
GFP_MOVABLE|GFP_RECLAIMABLE to be shiftable into MIGRATE_* enum values, so
add some more BUILD_BUG_ONs to reflect this assumption.

Link: https://linux-review.googlesource.com/id/Iae64e2182f75c3aca776a486b71a72571d66d83e
Link: https://lkml.kernel.org/r/20220726230241.3770532-1-pcc@google.com


Signed-off-by: default avatarPeter Collingbourne <pcc@google.com>
Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
parent 24a95998

include/linux/gfp.h

+3 −0
Original line number Diff line number Diff line
@@ -18,6 +18,9 @@ static inline int gfp_migratetype(const gfp_t gfp_flags) 
	VM_WARN_ON((gfp_flags & GFP_MOVABLE_MASK) == GFP_MOVABLE_MASK);

	BUILD_BUG_ON((1UL << GFP_MOVABLE_SHIFT) != ___GFP_MOVABLE);

	BUILD_BUG_ON((___GFP_MOVABLE >> GFP_MOVABLE_SHIFT) != MIGRATE_MOVABLE);

	BUILD_BUG_ON((___GFP_RECLAIMABLE >> GFP_MOVABLE_SHIFT) != MIGRATE_RECLAIMABLE);

	BUILD_BUG_ON(((___GFP_MOVABLE | ___GFP_RECLAIMABLE) >>

		      GFP_MOVABLE_SHIFT) != MIGRATE_HIGHATOMIC);



	if (unlikely(page_group_by_mobility_disabled))

		return MIGRATE_UNMOVABLE;