Re: [mm-unstable v4 5/5] mm: memcg: restore subtree stats flushing

[Waiman Long]

On 12/1/23 20:57, Bagas Sanjaya wrote:
> > -void mem_cgroup_flush_stats(void)
> > +/*
> > + * mem_cgroup_flush_stats - flush the stats of a memory cgroup subtree
> > + * @memcg: root of the subtree to flush
> > + *
> > + * Flushing is serialized by the underlying global rstat lock. There is also a
> > + * minimum amount of work to be done even if there are no stat updates to flush.
> > + * Hence, we only flush the stats if the updates delta exceeds a threshold. This
> > + * avoids unnecessary work and contention on the underlying lock.
> > + */
> What is global rstat lock?

It is the cgroup_rstat_lock in kernel/cgroup/rstat.c.

Cheers,
Longman