Commit f8eb145e authored by Tejun Heo's avatar Tejun Heo Committed by Greg Kroah-Hartman
Browse files

kernfs: Factor out kernfs_activate_one() 



Factor out kernfs_activate_one() from kernfs_activate() and reorder
operations so that KERNFS_ACTIVATED now simply indicates whether activation
was attempted on the node ignoring whether activation took place. As the
flag doesn't have a reader, the refactoring and reordering shouldn't cause
any behavior difference.

Tested-by: default avatarChengming Zhou <zhouchengming@bytedance.com>
Reviewed-by: default avatarChengming Zhou <zhouchengming@bytedance.com>
Signed-off-by: default avatarTejun Heo <tj@kernel.org>
Link: https://lore.kernel.org/r/20220828050440.734579-8-tj@kernel.org


Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
parent c2549174

fs/kernfs/dir.c

+17 −10
Original line number Diff line number Diff line
@@ -1305,6 +1305,21 @@ static struct kernfs_node *kernfs_next_descendant_post(struct kernfs_node *pos, 
	return pos->parent;

}



static void kernfs_activate_one(struct kernfs_node *kn)

{

	lockdep_assert_held_write(&kernfs_root(kn)->kernfs_rwsem);



	kn->flags |= KERNFS_ACTIVATED;



	if (kernfs_active(kn) || (kn->flags & KERNFS_REMOVING))

		return;



	WARN_ON_ONCE(kn->parent && RB_EMPTY_NODE(&kn->rb));

	WARN_ON_ONCE(atomic_read(&kn->active) != KN_DEACTIVATED_BIAS);



	atomic_sub(KN_DEACTIVATED_BIAS, &kn->active);

}



/**

 * kernfs_activate - activate a node which started deactivated

 * @kn: kernfs_node whose subtree is to be activated
@@ -1326,16 +1341,8 @@ void kernfs_activate(struct kernfs_node *kn) 
	down_write(&root->kernfs_rwsem);



	pos = NULL;

	while ((pos = kernfs_next_descendant_post(pos, kn))) {

		if (kernfs_active(pos) || (pos->flags & KERNFS_REMOVING))

			continue;



		WARN_ON_ONCE(pos->parent && RB_EMPTY_NODE(&pos->rb));

		WARN_ON_ONCE(atomic_read(&pos->active) != KN_DEACTIVATED_BIAS);



		atomic_sub(KN_DEACTIVATED_BIAS, &pos->active);

		pos->flags |= KERNFS_ACTIVATED;

	}

	while ((pos = kernfs_next_descendant_post(pos, kn)))

		kernfs_activate_one(pos);



	up_write(&root->kernfs_rwsem);

}