From: Keir Fraser <keir@xen.org>
Date: Fri, 17 Dec 2010 10:08:41 +0000 (+0000)
Subject: xen/netback: Re-factor net_tx_action_dealloc() slightly
X-Git-Url: http://xenbits.xensource.com/gitweb?a=commitdiff_plain;h=456eb7a570b349e76f338041eba94463bd702a61;p=legacy%2Flinux-2.6.18-xen.git

xen/netback: Re-factor net_tx_action_dealloc() slightly

There is no need for processing of the pending_inuse list to be within
the dealloc_prod/cons loop.

Signed-off-by: Paul Durrant <paul.durrant@citrix.com>
Signed-off-by: Jan Beulich <jbeulich@novell.com>
---

diff --git a/drivers/xen/netback/netback.c b/drivers/xen/netback/netback.c
index 34d8d1df..154c7fbe 100644
--- a/drivers/xen/netback/netback.c
+++ b/drivers/xen/netback/netback.c
@@ -915,7 +915,6 @@ inline static void net_tx_action_dealloc(void)
 	u16 pending_idx;
 	PEND_RING_IDX dc, dp;
 	netif_t *netif;
-	int ret;
 	LIST_HEAD(list);
 
 	dc = dealloc_cons;
@@ -950,11 +949,17 @@ inline static void net_tx_action_dealloc(void)
 			gop++;
 		}
 
-		if (netbk_copy_skb_mode != NETBK_DELAYED_COPY_SKB ||
-		    list_empty(&pending_inuse_head))
-			break;
+	} while (dp != dealloc_prod);
+
+	dealloc_cons = dc;
+
+	if (HYPERVISOR_grant_table_op(GNTTABOP_unmap_grant_ref,
+				      tx_unmap_ops, gop - tx_unmap_ops))
+		BUG();
 
-		/* Copy any entries that have been pending for too long. */
+	/* Copy any entries that have been pending for too long. */
+	if (netbk_copy_skb_mode == NETBK_DELAYED_COPY_SKB &&
+	    !list_empty(&pending_inuse_head)) {
 		list_for_each_entry_safe(inuse, n, &pending_inuse_head, list) {
 			if (time_after(inuse->alloc_time + HZ / 2, jiffies))
 				break;
@@ -976,13 +981,7 @@ inline static void net_tx_action_dealloc(void)
 
 			break;
 		}
-	} while (dp != dealloc_prod);
-
-	dealloc_cons = dc;
-
-	ret = HYPERVISOR_grant_table_op(
-		GNTTABOP_unmap_grant_ref, tx_unmap_ops, gop - tx_unmap_ops);
-	BUG_ON(ret);
+	}
 
 	list_for_each_entry_safe(inuse, n, &list, list) {
 		pending_idx = inuse - pending_inuse;