net: Rearrange loop in net_rx_action
authorHerbert Xu <herbert@gondor.apana.org.au>
Sat, 20 Dec 2014 20:16:25 +0000 (07:16 +1100)
committerDavid S. Miller <davem@davemloft.net>
Wed, 24 Dec 2014 04:20:21 +0000 (23:20 -0500)
This patch rearranges the loop in net_rx_action to reduce the
amount of jumping back and forth when reading the code.

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
net/core/dev.c

index b85eba9dfd88a52335fa5bb69e4a36833dfcdbaf..c97ae6fec040f493655f7c039f810b2bc5461b62 100644 (file)
@@ -4631,9 +4631,15 @@ static void net_rx_action(struct softirq_action *h)
        list_splice_init(&sd->poll_list, &list);
        local_irq_enable();
 
-       while (!list_empty(&list)) {
+       for (;;) {
                struct napi_struct *n;
 
+               if (list_empty(&list)) {
+                       if (!sd_has_rps_ipi_waiting(sd) && list_empty(&repoll))
+                               return;
+                       break;
+               }
+
                n = list_first_entry(&list, struct napi_struct, poll_list);
                budget -= napi_poll(n, &repoll);
 
@@ -4641,15 +4647,13 @@ static void net_rx_action(struct softirq_action *h)
                 * Allow this to run for 2 jiffies since which will allow
                 * an average latency of 1.5/HZ.
                 */
-               if (unlikely(budget <= 0 || time_after_eq(jiffies, time_limit)))
-                       goto softnet_break;
+               if (unlikely(budget <= 0 ||
+                            time_after_eq(jiffies, time_limit))) {
+                       sd->time_squeeze++;
+                       break;
+               }
        }
 
-       if (!sd_has_rps_ipi_waiting(sd) &&
-           list_empty(&list) &&
-           list_empty(&repoll))
-               return;
-out:
        local_irq_disable();
 
        list_splice_tail_init(&sd->poll_list, &list);
@@ -4659,12 +4663,6 @@ out:
                __raise_softirq_irqoff(NET_RX_SOFTIRQ);
 
        net_rps_action_and_irq_enable(sd);
-
-       return;
-
-softnet_break:
-       sd->time_squeeze++;
-       goto out;
 }
 
 struct netdev_adjacent {