The differences between nested and !nested will become larger in
later changes so split them out for readability.
Signed-off-by: NNicholas Piggin <npiggin@gmail.com>
Reviewed-by: NFabiano Rosas <farosas@linux.ibm.com>
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20220303053315.1056880-5-npiggin@gmail.com