Use helper macro min and max to help simplify the code logic.  Minor
readability improvement.

Link: https://lkml.kernel.org/r/20220224121134.35068-1-linmiaohe@huawei.comSigned-off-by: Miaohe Lin <linmiaohe@huawei.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>