On Fri 10-12-21 16:22:01, Sebastian Andrzej Siewior wrote: [...] I am sorry but I didn't get to read and digest the rest of the message yet. Let me just point out this > The problematic part here is mem_cgroup_tree_per_node::lock which can > not be acquired with disabled interrupts on PREEMPT_RT. The "locking > scope" is not always clear to me. Also, if it is _just_ the counter, > then we might solve this differently. I do not think you should be losing sleep over soft limit reclaim. This is certainly not something to be used for RT workloads and rather than touching that code I think it makes some sense to simply disallow soft limit with RT enabled (i.e. do not allow to set any soft limit). -- Michal Hocko SUSE Labs
