On Fri, Jul 26, 2019 at 08:30:48PM +0200, Thomas Gleixner wrote: > The following series brings the bulk of PREEMPT_RT specific changes for the > (hr)timer code: > > - Handle timer deletion correctly under RT to avoid priority inversion > and life locks > > This mechanism might be useful for VMs as well when a vCPU > executing a timer callback gets scheduled out and on another vCPU > del_timer_sync() or hrtimer_cancel() is invoked. > > The mitigation would only work when paravirt spinlocks are > enabled. I've not implemented that, as I don't know whether this is a > real world issue. I just noticed that it is basically the same > problem. Adding it would be trivial. > > - Prepare for moving most hrtimer callbacks into softirq context and mark > timers which need to expire in hard interrupt context even on RT so > they don't get moved. >
Acked-by: Peter Zijlstra (Intel) <[email protected]>
