On Thu, Jun 12, 2014 at 02:32:13PM +0800, Li Zefan wrote: > @@ -1677,6 +1679,22 @@ static struct dentry *cgroup_mount(struct file_system_type *fs_type, > goto out_unlock; > } > > + /* > + * If some subsystems have been bound to existing cgroup hierarchies, > + * but those hierachies are being destroyed, let's wait a little bit > + * and retry. > + */ > + for_each_subsys(ss, i) { > + if (!(opts.subsys_mask & (1 << i))) > + continue; > + if (!percpu_ref_alive(&ss->root->cgrp.self.refcnt)) { Can't we just do tryget_live() instead and then put before retrying? It's not exactly a hot path and the operations are dirt cheap anyway. Thanks. -- tejun -- To unsubscribe from this list: send the line "unsubscribe cgroups" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html