On Fri, Jul 16, 2021 at 02:02:50PM -0400, Waiman Long wrote: > On 7/14/21 9:54 AM, Frederic Weisbecker wrote: > > The fact that "isolcpus=" behaviour can't be modified at runtime is an > > eternal source of discussion and debate opposing a useful feature against > > a terrible interface. > > > > I've long since tried to figure out a proper way to control this at > > runtime using cpusets, which isn't easy as a boot time single cpumask > > is difficult to map to a hierarchy of cpusets that can even overlap. > > I have a cpuset patch that allow disabling of load balancing in a cgroup-v2 > setting: > > https://lore.kernel.org/lkml/20210621184924.27493-1-longman@xxxxxxxxxx/ > > The idea of cpuset partition is that there will be no overlap of cpus in > different partitions. So there will be no confusion whether a cpu is > load-balanced or not. Oh ok I missed that, time for me to check your patchset. Thanks! > > > > > The idea here is to map the boot-set isolation behaviour to any cpuset > > directory whose cpumask is a subset of "isolcpus=". I let you browse > > for details on the last patch. > > > > Note this is still WIP and half-baked, but I figured it's important to > > validate the interface early. > > Using different cpumasks for different isolated properties is the easy part. > The hard part is to make different subsystems to change their behavior as > the isolation masks change dynamically at run time. Currently, they check > the housekeeping cpumask only at boot time or when certain events happen. > > Cheers, > Longman > >
