afs: Add some callback management tracepoints

Add a couple of tracepoints to track callback management:

 (1) afs_cb_miss - Logs when we were unable to apply a callback, either due
     to the inode being discarded or due to a competing thread applying a
     callback first.

 (2) afs_cb_break - Logs when we attempted to clear the noted callback
     promise, either due to the server explicitly breaking the callback,
     the callback promise lapsing or a local event obsoleting it.

Signed-off-by: David Howells <dhowells@redhat.com>

1 files changed, 2 insertions, 2 deletions

diff --git a/fs/afs/dir.c b/fs/afs/dir.c
index 93fd51c3bdae..e8c58c94eb61 100644
--- a/fs/afs/dir.c
+++ b/fs/afs/dir.c
@@ -1367,12 +1367,12 @@ static int afs_dir_remove_link(struct afs_vnode *dvnode, struct dentry *dentry,
 			drop_nlink(&vnode->vfs_inode);
 			if (vnode->vfs_inode.i_nlink == 0) {
 				set_bit(AFS_VNODE_DELETED, &vnode->flags);
-				__afs_break_callback(vnode);
+				__afs_break_callback(vnode, afs_cb_break_for_unlink);
 			}
 			write_sequnlock(&vnode->cb_lock);
 			ret = 0;
 		} else {
-			afs_break_callback(vnode);
+			afs_break_callback(vnode, afs_cb_break_for_unlink);
 
 			if (test_bit(AFS_VNODE_DELETED, &vnode->flags))
 				kdebug("AFS_VNODE_DELETED");