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charset=us-ascii Content-Disposition: inline In-Reply-To: <9629f060-28f4-4743-9e60-688cba039f87@arm.com> On 13/02/25 13:38, Christian Loehle wrote: > On 2/13/25 13:33, Juri Lelli wrote: ... > > Not sure I get what your worry is, sorry. In my understanding when the > > last cpu of a policy/cluster gets offlined the corresponding sugov > > kthread gets stopped as well (sugov_exit)? > > > > The other way round. > We may have sugov kthread of cluster [6,7] affined to CPU1. Is it > guaranteed that we cannot offline CPU1 (while CPU6 or CPU7 are still > online)? Uhu, is this a sane/desired setup? Anyway, I would say that if CPU1 is offlined sugov[6,7] will need to be migrated someplace else. > Or without the affinity: > cluster [6,7] with isolcpu=6 (i.e. sugov kthread of that cluster can > only run on CPU7). Is offlining of CPU6 then prevented (as long as > CPU7 is online)? > I don't see how. > Anyway we probably want to change isolcpu and affinity to merely be > a suggestion for the sugov DL case. Fundamentally it belongs to what > is run on that CPU anyway. I would tend to agree.