On Sat, 2018-04-21 at 22:55 +0800, jianchao.wang wrote: > So we have a __deadline as below: > > deadline gen state > > ______________|____|_| > > \___ __/ > V > granularity > > and even we usually have a 30~60s timeout, > but we should support a 1s granularity at least. > How to decide the granularity ? Your diagram shows that the uppermost bits are used for the deadline. What I proposed is to use the lower 32 bits for the deadline such that we again have a resolution of 1/HZ. Bart.