[PATCH 2/6] s390/ctcm: Put struct qllc on stack.

[Sebastian Andrzej Siewior <bigeasy@xxxxxxxxxxxxx>]

The size of struct qllc is 2 byte. The memory for is allocated, initialized,
used and deallocated a few lines later.

It is more efficient to avoid the allocation/free dance and keeping the
variable on stack. Especially since the compiler is smart enough to not
allocate the memory on stack but assign the values directly.

Rename `qllcptr' to `qllc' and use it on stack.

Signed-off-by: Sebastian Andrzej Siewior <bigeasy@xxxxxxxxxxxxx>
---
 drivers/s390/net/ctcm_mpc.c | 24 ++++++------------------
 1 file changed, 6 insertions(+), 18 deletions(-)

diff --git a/drivers/s390/net/ctcm_mpc.c b/drivers/s390/net/ctcm_mpc.c
index 04a51cc89e74c..4ff51af44d338 100644
--- a/drivers/s390/net/ctcm_mpc.c
+++ b/drivers/s390/net/ctcm_mpc.c
@@ -2049,11 +2049,10 @@ static void mpc_action_rcvd_xid7(fsm_instance *fsm, int event, void *arg)
  */
 static int mpc_send_qllc_discontact(struct net_device *dev)
 {
-	__u32	new_len	= 0;
 	struct sk_buff   *skb;
-	struct qllc      *qllcptr;
 	struct ctcm_priv *priv = dev->ml_priv;
 	struct mpc_group *grp = priv->mpcg;
+	struct qllc	qllc;
 
 	CTCM_PR_DEBUG("%s: GROUP STATE: %s\n",
 		__func__, mpcg_state_names[grp->saved_state]);
@@ -2080,31 +2079,20 @@ static int mpc_send_qllc_discontact(struct net_device *dev)
 	case MPCG_STATE_FLOWC:
 	case MPCG_STATE_READY:
 		grp->send_qllc_disc = 2;
-		new_len = sizeof(struct qllc);
-		qllcptr = kzalloc(new_len, gfp_type() | GFP_DMA);
-		if (qllcptr == NULL) {
-			CTCM_DBF_TEXT_(MPC_ERROR, CTC_DBF_ERROR,
-				"%s(%s): qllcptr allocation error",
-						CTCM_FUNTAIL, dev->name);
-			return -ENOMEM;
-		}
-
-		qllcptr->qllc_address = 0xcc;
-		qllcptr->qllc_commands = 0x03;
-
-		skb = __dev_alloc_skb(new_len, GFP_ATOMIC);
 
+		skb = __dev_alloc_skb(sizeof(struct qllc), GFP_ATOMIC);
 		if (skb == NULL) {
 			CTCM_DBF_TEXT_(MPC_ERROR, CTC_DBF_ERROR,
 				"%s(%s): skb allocation error",
 						CTCM_FUNTAIL, dev->name);
 			priv->stats.rx_dropped++;
-			kfree(qllcptr);
 			return -ENOMEM;
 		}
 
-		skb_put_data(skb, qllcptr, new_len);
-		kfree(qllcptr);
+		qllc.qllc_address = 0xcc;
+		qllc.qllc_commands = 0x03;
+
+		skb_put_data(skb, &qllc, sizeof(struct qllc));
 
 		if (skb_headroom(skb) < 4) {
 			CTCM_DBF_TEXT_(MPC_ERROR, CTC_DBF_ERROR,
-- 
2.29.2