On Mon, Nov 23 2020 at 17:58, Alex Belits wrote: > From: Yuri Norov <ynorov@xxxxxxxxxxx> > > For nohz_full CPUs the desirable behavior is to receive interrupts > generated by tick_nohz_full_kick_cpu(). But for hard isolation it's > obviously not desirable because it breaks isolation. > > This patch adds check for it. git grep 'This patch' Documentation/process/ > */ > void tick_nohz_full_kick_cpu(int cpu) > { > - if (!tick_nohz_full_cpu(cpu)) > + smp_rmb(); Undocumented smp_rmb() ... > + if (!tick_nohz_full_cpu(cpu) || task_isolation_on_cpu(cpu)) > return; I still have to see a convincing argument why task isolation is special and not just a straight forward extension of NOHZ full cpu isolation. It's not special as much as you want it to be special. Thanks, tglx