Hi Waiman. On Wed, Nov 26, 2025 at 02:43:50PM -0500, Waiman Long <[email protected]> wrote: > Modification to cpumasks are all serialized by the cpuset_mutex. If you are > referring to 2 or more tasks doing parallel updates to various cpuset > control files of sibling cpusets, the results can actually vary depending on > the actual serialization results of those operations.
I meant the latter when the difference in results when concurrent tasks do the update (e.g. two containers start in parallel), I don't see an issue with the race wrt consistency of in-kernel data. We're on the same page here. > One difference between cpuset.cpus and cpuset.cpus.exclusive is the fact > that operations on cpuset.cpus.exclusive can fail if the result is not > exclusive WRT sibling cpusets, but becoming a valid partition is guaranteed > unless none of the exclusive CPUs are passed down from the parent. The use > of cpuset.cpus.exclusive is required for creating remote partition. > > OTOH, changes to cpuset.cpus will never fail, but becoming a valid partition > root is not guaranteed and is limited to the creation of local partition > only. > > Does that answer your question? It does help my understanding. Do you envision that remote and local partitions should be used together (in one subtree)? Thanks, Michal
signature.asc
Description: PGP signature
