Commit 838d992b authored by Marc Zyngier's avatar Marc Zyngier
Browse files

KVM: arm64: Convert kvm_mpidr_index() to bitmap_gather() 



Linux 6.9 has introduced new bitmap manipulation helpers, with
bitmap_gather() being of special interest, as it does exactly
what kvm_mpidr_index() is already doing.

Make the latter a wrapper around the former.

Reviewed-by: default avatarOliver Upton <oliver.upton@linux.dev>
Link: https://lore.kernel.org/r/20240502154247.3012042-1-maz@kernel.org


Signed-off-by: default avatarMarc Zyngier <maz@kernel.org>
parent 03b3d00a

arch/arm64/include/asm/kvm_host.h

+3 −13
Original line number Diff line number Diff line
@@ -220,20 +220,10 @@ struct kvm_mpidr_data { 


static inline u16 kvm_mpidr_index(struct kvm_mpidr_data *data, u64 mpidr)

{

	unsigned long mask = data->mpidr_mask;

	u64 aff = mpidr & MPIDR_HWID_BITMASK;

	int nbits, bit, bit_idx = 0;

	u16 index = 0;

	unsigned long index = 0, mask = data->mpidr_mask;

	unsigned long aff = mpidr & MPIDR_HWID_BITMASK;



	/*

	 * If this looks like RISC-V's BEXT or x86's PEXT

	 * instructions, it isn't by accident.

	 */

	nbits = fls(mask);

	for_each_set_bit(bit, &mask, nbits) {

		index |= (aff & BIT(bit)) >> (bit - bit_idx);

		bit_idx++;

	}

	bitmap_gather(&index, &aff, &mask, fls(mask));



	return index;

}