aboutsummaryrefslogtreecommitdiffstats
path: root/net/core
diff options
context:
space:
mode:
authorMatt Mackall <mpm@selenic.com>2005-08-11 22:27:43 -0400
committerDavid S. Miller <davem@davemloft.net>2005-08-11 22:27:43 -0400
commit53fb95d3c14290fd6ee808b221e35493f096246f (patch)
tree146c31c79bbc66d8fde3afa5ae37a04b63041eba /net/core
parent2652076507b662fc88ba16c27b59c7bdd9ccd956 (diff)
[NETPOLL]: fix initialization/NAPI race
This fixes a race during initialization with the NAPI softirq processing by using an RCU approach. This race was discovered when refill_skbs() was added to the setup code. Signed-off-by: Matt Mackall <mpm@selenic.com> Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'net/core')
-rw-r--r--net/core/dev.c9
-rw-r--r--net/core/netpoll.c3
2 files changed, 8 insertions, 4 deletions
diff --git a/net/core/dev.c b/net/core/dev.c
index 52a3bf7ae177..faf59b02c4bf 100644
--- a/net/core/dev.c
+++ b/net/core/dev.c
@@ -1696,7 +1696,8 @@ static void net_rx_action(struct softirq_action *h)
1696 struct softnet_data *queue = &__get_cpu_var(softnet_data); 1696 struct softnet_data *queue = &__get_cpu_var(softnet_data);
1697 unsigned long start_time = jiffies; 1697 unsigned long start_time = jiffies;
1698 int budget = netdev_budget; 1698 int budget = netdev_budget;
1699 1699 void *have;
1700
1700 local_irq_disable(); 1701 local_irq_disable();
1701 1702
1702 while (!list_empty(&queue->poll_list)) { 1703 while (!list_empty(&queue->poll_list)) {
@@ -1709,10 +1710,10 @@ static void net_rx_action(struct softirq_action *h)
1709 1710
1710 dev = list_entry(queue->poll_list.next, 1711 dev = list_entry(queue->poll_list.next,
1711 struct net_device, poll_list); 1712 struct net_device, poll_list);
1712 netpoll_poll_lock(dev); 1713 have = netpoll_poll_lock(dev);
1713 1714
1714 if (dev->quota <= 0 || dev->poll(dev, &budget)) { 1715 if (dev->quota <= 0 || dev->poll(dev, &budget)) {
1715 netpoll_poll_unlock(dev); 1716 netpoll_poll_unlock(have);
1716 local_irq_disable(); 1717 local_irq_disable();
1717 list_del(&dev->poll_list); 1718 list_del(&dev->poll_list);
1718 list_add_tail(&dev->poll_list, &queue->poll_list); 1719 list_add_tail(&dev->poll_list, &queue->poll_list);
@@ -1721,7 +1722,7 @@ static void net_rx_action(struct softirq_action *h)
1721 else 1722 else
1722 dev->quota = dev->weight; 1723 dev->quota = dev->weight;
1723 } else { 1724 } else {
1724 netpoll_poll_unlock(dev); 1725 netpoll_poll_unlock(have);
1725 dev_put(dev); 1726 dev_put(dev);
1726 local_irq_disable(); 1727 local_irq_disable();
1727 } 1728 }
diff --git a/net/core/netpoll.c b/net/core/netpoll.c
index c02a08da6d42..996787bca17f 100644
--- a/net/core/netpoll.c
+++ b/net/core/netpoll.c
@@ -732,6 +732,9 @@ int netpoll_setup(struct netpoll *np)
732 /* last thing to do is link it to the net device structure */ 732 /* last thing to do is link it to the net device structure */
733 ndev->npinfo = npinfo; 733 ndev->npinfo = npinfo;
734 734
735 /* avoid racing with NAPI reading npinfo */
736 synchronize_rcu();
737
735 return 0; 738 return 0;
736 739
737 release: 740 release: