> > ms granularity seems very coarse grained for this. Surely > > at some point of spinning you can afford a ktime_get? But ok. > We are reading time when we are at the head of the (main) queue, but > don’t have the lock yet. Not sure about the latency of ktime_get(), but > anything reasonably fast but not necessarily precise should work.
Actually cpu_clock / sched_clock (see my other email). These should be fast without corner cases and also monotonic. > > > Could you turn that into a moduleparm which can be changed at runtime? > > Would be strange to have to reboot just to play with this parameter > Yes, good suggestion, thanks. > > > This would also make the code a lot shorter I guess. > So you don’t think we need the command-line parameter, just the module_param? module_params can be changed at the command line too, so yes. -Andi
