arm64/sve: Skip flushing Z registers with 128 bit vectors

When the SVE vector length is 128 bits then there are no bits in the Z
registers which are not shared with the V registers so we can skip them
when zeroing state not shared with FPSIMD, this results in a minor
performance improvement.

Signed-off-by: Mark Brown <>
Reviewed-by: Dave Martin <>
Acked-by: Catalin Marinas <>
Signed-off-by: Will Deacon <>
3 files changed