On Mon, Feb 22, 2010 at 01:07:32PM -0500, Vivek Goyal wrote: > > > > +unsigned long mem_cgroup_dirty_bytes(void) > > > > +{ > > > > + struct mem_cgroup *memcg; > > > > + unsigned long dirty_bytes; > > > > + > > > > + if (mem_cgroup_disabled()) > > > > + return vm_dirty_bytes; > > > > + > > > > + rcu_read_lock(); > > > > + memcg = mem_cgroup_from_task(current); > > > > + if (memcg == NULL) > > > > + dirty_bytes = vm_dirty_bytes; > > > > + else > > > > + dirty_bytes = get_dirty_bytes(memcg); > > > > + rcu_read_unlock(); > > > > > > The rcu_read_lock() isn't protecting anything here. > > > > Right! > > Are we not protecting "memcg" pointer using rcu here? Vivek, you are right: mem_cgroup_from_task() -> task_subsys_state() -> rcu_dereference() So, this *must* be RCU protected. Thanks! -Andrea _______________________________________________ Containers mailing list Containers@xxxxxxxxxxxxxxxxxxxxxxxxxx https://lists.linux-foundation.org/mailman/listinfo/containers