On Thu, Feb 20, 2025 at 10:14:45AM -0800, JP Kobryn wrote: > On 2/20/25 9:59 AM, Yosry Ahmed wrote: > > On Thu, Feb 20, 2025 at 09:53:33AM -0800, Shakeel Butt wrote: > > > On Thu, Feb 20, 2025 at 05:26:04PM +0000, Yosry Ahmed wrote: > > > > > > > > Another question is, does it make sense to keep BPF flushing in the > > > > "self" css with base stats flushing for now? IIUC BPF flushing is not > > > > very popular now anyway, and doing so will remove the need to support > > > > flushing and updating things that are not css's. Just food for thought. > > > > > > > > > > Oh if this simplifies the code, I would say go for it. > > > > I think we wouldn't need cgroup_rstat_ops and some of the refactoring > > may not be needed. It will also reduce the memory overhead, and keep it > > constant regardless of using BPF which is nice. > > Yes, this is true. cgroup_rstat_ops was only added to allow cgroup_bpf > to make use of rstat. If the bpf flushing remains tied to > cgroup_subsys_state::self, then the ops interface and supporting code > can be removed. Probably stating the obvious but the trade-off would be > that if bpf cgroups are in use, they would account for some extra > overhead while flushing the base stats. Is Google making use of bpf- > based cgroups? Ironically I don't know, but I don't expect the BPF flushing to be expensive enough to affect this. If someone has the use case that loads enough BPF programs to cause a noticeable impact, we can address it then. This series will still be an improvement anyway.
