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> > } > > > > + if (!cpu_online(cpu_of(rq))) > > + return -EBUSY; > > + > > update_rq_clock(rq); > > dl_server_stop(dl_se); > > retval = dl_server_apply_params(dl_se, runtime, period, 0); > > I was looking at Sashiko findings and wondered what to do about this as > well. I think what you are proposing should be fine, unless for some > reason one wants to tweak dl-server parameters before swithcing a CPU > on. but since hotplug it's a disruptive operation already, I would say > imposing to make such a change after CPU is online should be ok (and > simpler to get right from a bandwidth accounting pov). > > Reviewed-by: Juri Lelli If this makes sense to you, could you add it to your queue:sched/core? Otherwise it's possible to trigger the issues above by changing dl_server bandwidth for offline CPUs. Thanks, -Andrea