nfsd: use clear_and_wake_up_bit()

nfsd has two places that open-code clear_and_wake_up_bit().  One has
the required memory barriers.  The other does not.

Change both to use clear_and_wake_up_bit() so we have the barriers
without the noise.
Signed-off-by: NeilBrown <neilb@suse.de>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>

fs/nfsd/nfs4recover.c

@@ -1895,10 +1895,7 @@ nfsd4_cltrack_upcall_lock(struct nfs4_client *clp)
 static void
 nfsd4_cltrack_upcall_unlock(struct nfs4_client *clp)
 {
-	smp_mb__before_atomic();
-	clear_bit(NFSD4_CLIENT_UPCALL_LOCK, &clp->cl_flags);
-	smp_mb__after_atomic();
-	wake_up_bit(&clp->cl_flags, NFSD4_CLIENT_UPCALL_LOCK);
+	clear_and_wake_up_bit(NFSD4_CLIENT_UPCALL_LOCK, &clp->cl_flags);
 }
 
 static void

fs/nfsd/nfs4state.c

@@ -3079,8 +3079,7 @@ nfsd4_cb_getattr_release(struct nfsd4_callback *cb)
 	struct nfs4_delegation *dp =
 			container_of(ncf, struct nfs4_delegation, dl_cb_fattr);
 
-	clear_bit(CB_GETATTR_BUSY, &ncf->ncf_cb_flags);
-	wake_up_bit(&ncf->ncf_cb_flags, CB_GETATTR_BUSY);
+	clear_and_wake_up_bit(CB_GETATTR_BUSY, &ncf->ncf_cb_flags);
 	nfs4_put_stid(&dp->dl_stid);
 }