On 2013/7/30 2:28, Tejun Heo wrote: > Hello, > > On Mon, Jul 29, 2013 at 03:07:48PM +0800, Li Zefan wrote: >> @@ -4590,6 +4599,9 @@ static void cgroup_offline_fn(struct work_struct *work) >> /* delete this cgroup from parent->children */ >> list_del_rcu(&cgrp->sibling); >> >> + if (cgrp->id) >> + idr_remove(&cgrp->root->cgroup_idr, cgrp->id); >> + > > Yeap, if we're gonna allow lookups, removal should happen here but can > we please add short comment explaining why that is? sure > Also, do we want to clear cgrp->id? > Set cgrp->id to 0? No, 0 is a valid id. The if is here because at first I called idr_alloc() very late in cgroup_create(), so cgroup_offline_fn() can be called while cgrp->id hasn't been initialized. Now I can remove this check. -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@xxxxxxxxx. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: <a href=mailto:"dont@xxxxxxxxx";> email@xxxxxxxxx </a>