powerpc/mm/slice: Remove intermediate bitmap copy (326691ad) · Commits · 戴 / test

bitmap_or() and bitmap_andnot() can work properly with dst identical to src1 or src2. There is no need of an intermediate result bitmap that is copied back to dst in a second step. Signed-off-by:

Christophe Leroy <christophe.leroy@c-s.fr> Reviewed-by:

Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com> Reviewed-by:

Nicholas Piggin <npiggin@gmail.com> Signed-off-by:

Michael Ellerman <mpe@ellerman.id.au>

arch/powerpc/mm/slice.c

+4 −8

Original line number	Diff line number	Diff line
		@@ -388,21 +388,17 @@ static unsigned long slice_find_area(struct mm_struct *mm, unsigned long len,

		static inline void slice_or_mask(struct slice_mask dst, struct slice_mask src)
		{
		DECLARE_BITMAP(result, SLICE_NUM_HIGH);

		dst->low_slices \|= src->low_slices;
		bitmap_or(result, dst->high_slices, src->high_slices, SLICE_NUM_HIGH);
		bitmap_copy(dst->high_slices, result, SLICE_NUM_HIGH);
		bitmap_or(dst->high_slices, dst->high_slices, src->high_slices,
		SLICE_NUM_HIGH);
		}

		static inline void slice_andnot_mask(struct slice_mask dst, struct slice_mask src)
		{
		DECLARE_BITMAP(result, SLICE_NUM_HIGH);

		dst->low_slices &= ~src->low_slices;

		bitmap_andnot(result, dst->high_slices, src->high_slices, SLICE_NUM_HIGH);
		bitmap_copy(dst->high_slices, result, SLICE_NUM_HIGH);
		bitmap_andnot(dst->high_slices, dst->high_slices, src->high_slices,
		SLICE_NUM_HIGH);
		}

		#ifdef CONFIG_PPC_64K_PAGES

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