diff options
| author | Tejun Heo <tj@kernel.org> | 2014-02-03 14:02:55 -0500 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2014-02-07 15:42:40 -0800 |
| commit | abd54f028ec30976d6e797e7474ec91d96186a0c (patch) | |
| tree | 3fc9f5240ec0dfdcb210499878e08a18a678157f /include/linux/kernfs.h | |
| parent | a6607930b6cd829fc7f680b48a937d827e0bb931 (diff) | |
kernfs: replace kernfs_node->u.completion with kernfs_root->deactivate_waitq
kernfs_node->u.completion is used to notify deactivation completion
from kernfs_put_active() to kernfs_deactivate(). We now allow
multiple racing removals of the same node and the current removal
scheme is no longer correct - kernfs_remove() invocation may return
before the node is properly deactivated if it races against another
removal. The removal path will be restructured to address the issue.
To help such restructure which requires supporting multiple waiters,
this patch replaces kernfs_node->u.completion with
kernfs_root->deactivate_waitq. This makes deactivation event
notifications share a per-root waitqueue_head; however, the wait path
is quite cold and this will also allow shaving one pointer off
kernfs_node.
v2: Refreshed on top of ("kernfs: make kernfs_deactivate() honor
KERNFS_LOCKDEP flag").
Signed-off-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'include/linux/kernfs.h')
| -rw-r--r-- | include/linux/kernfs.h | 4 |
1 files changed, 2 insertions, 2 deletions
diff --git a/include/linux/kernfs.h b/include/linux/kernfs.h index 5be9f0228a3b..295a3bf642ba 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/completion.h> +#include <linux/wait.h> struct file; struct dentry; @@ -92,7 +92,6 @@ struct kernfs_node { struct rb_node rb; union { - struct completion *completion; struct kernfs_node *removed_list; } u; @@ -133,6 +132,7 @@ 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 { |