On Mon, 2018-05-14 at 09:37 +0800, jianchao.wang wrote: > In addition, on a 64bit system, how do you set up the timer with a 32bit deadline ? If timeout handling occurs less than (1 << 31) / HZ seconds after a request has been submitted then a 32-bit variable is sufficient to store the deadline. If you want to verify the implementation, please have a look at the int32_t variables in blk_mq_check_expired(). Bart.