diff options
| -rw-r--r-- | fs/kernfs/dir.c | 27 | ||||
| -rw-r--r-- | include/linux/kernfs.h | 4 |
2 files changed, 18 insertions, 13 deletions
diff --git a/fs/kernfs/dir.c b/fs/kernfs/dir.c index ed62de6cdf8f..510b5062ef30 100644 --- a/fs/kernfs/dir.c +++ b/fs/kernfs/dir.c @@ -8,7 +8,6 @@ * This file is released under the GPLv2. */ -#include <linux/sched.h> #include <linux/fs.h> #include <linux/namei.h> #include <linux/idr.h> @@ -152,7 +151,6 @@ struct kernfs_node *kernfs_get_active(struct kernfs_node *kn) */ void kernfs_put_active(struct kernfs_node *kn) { - struct kernfs_root *root = kernfs_root(kn); int v; if (unlikely(!kn)) @@ -164,7 +162,11 @@ void kernfs_put_active(struct kernfs_node *kn) if (likely(v != KN_DEACTIVATED_BIAS)) return; - wake_up_all(&root->deactivate_waitq); + /* + * atomic_dec_return() is a mb(), we'll always see the updated + * kn->u.completion. + */ + complete(kn->u.completion); } /** @@ -175,22 +177,26 @@ void kernfs_put_active(struct kernfs_node *kn) */ static void kernfs_deactivate(struct kernfs_node *kn) { - struct kernfs_root *root = kernfs_root(kn); + DECLARE_COMPLETION_ONSTACK(wait); + int v; BUG_ON(!(kn->flags & KERNFS_REMOVED)); if (!(kernfs_type(kn) & KERNFS_ACTIVE_REF)) return; - rwsem_acquire(&kn->dep_map, 0, 0, _RET_IP_); + kn->u.completion = (void *)&wait; - atomic_add(KN_DEACTIVATED_BIAS, &kn->active); + rwsem_acquire(&kn->dep_map, 0, 0, _RET_IP_); + /* atomic_add_return() is a mb(), put_active() will always see + * the updated kn->u.completion. + */ + v = atomic_add_return(KN_DEACTIVATED_BIAS, &kn->active); - if (atomic_read(&kn->active) != KN_DEACTIVATED_BIAS) + if (v != KN_DEACTIVATED_BIAS) { lock_contended(&kn->dep_map, _RET_IP_); - - wait_event(root->deactivate_waitq, - atomic_read(&kn->active) == KN_DEACTIVATED_BIAS); + wait_for_completion(&wait); + } lock_acquired(&kn->dep_map, _RET_IP_); rwsem_release(&kn->dep_map, 1, _RET_IP_); @@ -607,7 +613,6 @@ struct kernfs_root *kernfs_create_root(struct kernfs_dir_ops *kdops, void *priv) root->dir_ops = kdops; root->kn = kn; - init_waitqueue_head(&root->deactivate_waitq); return root; } diff --git a/include/linux/kernfs.h b/include/linux/kernfs.h index 232f1a632383..d2c439db4efa 100644 --- a/include/linux/kernfs.h +++ b/include/linux/kernfs.h @@ -15,7 +15,7 @@ #include <linux/lockdep.h> #include <linux/rbtree.h> #include <linux/atomic.h> -#include <linux/wait.h> +#include <linux/completion.h> struct file; struct iattr; @@ -91,6 +91,7 @@ struct kernfs_node { struct rb_node rb; union { + struct completion *completion; struct kernfs_node *removed_list; } u; @@ -131,7 +132,6 @@ struct kernfs_root { /* private fields, do not use outside kernfs proper */ struct ida ino_ida; struct kernfs_dir_ops *dir_ops; - wait_queue_head_t deactivate_waitq; }; struct kernfs_open_file { |