On Sat, Apr 13, 2019 at 01:22:50PM -0400, Waiman Long wrote: > +/* > + * The typical HZ value is either 250 or 1000. So set the minimum waiting > + * time to 4ms in the wait queue before initiating the handoff protocol. > + */ > +#define RWSEM_WAIT_TIMEOUT (HZ/250)
That seems equally unfortunate. For HZ=100 that results in 0ms, and for HZ=300 that results in 3 1/3-rd ms. (and this is not considering Alpha,ARM and MIPS, who all have various other 'creative' HZ values) In general aiming for sub 10ms timing using jiffies seems 'optimistic'.
