[PATCH] nfs: remove BKL from callback server

["J. Bruce Fields" <bfields@fieldses.org>]

From: J. Bruce Fields <bfields@citi.umich.edu>

The rpc server does not require that service threads take the BKL.

Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
---
 fs/nfs/callback.c |   12 ------------
 1 files changed, 0 insertions(+), 12 deletions(-)

Just noticed this while looking for something else.

If these BKL's were cut-and-pasted from lockd or older nfsd code under
the assumption that the generic rpc server code needed them: that
assumption was incorrect, and we should apply this patch.

(If there was some nfs-client-specific issue here, then ignore this
patch.)

diff --git a/fs/nfs/callback.c b/fs/nfs/callback.c
index 293fa05..e66ec5d 100644
--- a/fs/nfs/callback.c
+++ b/fs/nfs/callback.c
@@ -78,11 +78,6 @@ nfs4_callback_svc(void *vrqstp)
 
 	set_freezable();
 
-	/*
-	 * FIXME: do we really need to run this under the BKL? If so, please
-	 * add a comment about what it's intended to protect.
-	 */
-	lock_kernel();
 	while (!kthread_should_stop()) {
 		/*
 		 * Listen for a request on the socket
@@ -104,7 +99,6 @@ nfs4_callback_svc(void *vrqstp)
 		preverr = err;
 		svc_process(rqstp);
 	}
-	unlock_kernel();
 	return 0;
 }
 
@@ -160,11 +154,6 @@ nfs41_callback_svc(void *vrqstp)
 
 	set_freezable();
 
-	/*
-	 * FIXME: do we really need to run this under the BKL? If so, please
-	 * add a comment about what it's intended to protect.
-	 */
-	lock_kernel();
 	while (!kthread_should_stop()) {
 		prepare_to_wait(&serv->sv_cb_waitq, &wq, TASK_INTERRUPTIBLE);
 		spin_lock_bh(&serv->sv_cb_lock);
@@ -183,7 +172,6 @@ nfs41_callback_svc(void *vrqstp)
 		}
 		finish_wait(&serv->sv_cb_waitq, &wq);
 	}
-	unlock_kernel();
 	return 0;
 }
 
-- 
1.6.0.4