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author | Al Viro <viro@zeniv.linux.org.uk> | 2017-04-02 10:33:48 -0400 |
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committer | Al Viro <viro@zeniv.linux.org.uk> | 2017-04-02 10:33:48 -0400 |
commit | bee3f412d6fc94011850f16cddce745d529411a5 (patch) | |
tree | 01b1823a3bc0cb760129ed15f7ec027a36edc48b /drivers/net/xen-netback/interface.c | |
parent | d597580d373774b1bdab84b3d26ff0b55162b916 (diff) | |
parent | 476e75a44b56038bee9207242d4bc718f6b4de06 (diff) | |
download | lwn-bee3f412d6fc94011850f16cddce745d529411a5.tar.gz lwn-bee3f412d6fc94011850f16cddce745d529411a5.zip |
Merge branch 'parisc-4.11-3' of git://git.kernel.org/pub/scm/linux/kernel/git/deller/parisc-linux into uaccess.parisc
Diffstat (limited to 'drivers/net/xen-netback/interface.c')
-rw-r--r-- | drivers/net/xen-netback/interface.c | 26 |
1 files changed, 17 insertions, 9 deletions
diff --git a/drivers/net/xen-netback/interface.c b/drivers/net/xen-netback/interface.c index 829b26cd4549..8397f6c92451 100644 --- a/drivers/net/xen-netback/interface.c +++ b/drivers/net/xen-netback/interface.c @@ -165,13 +165,17 @@ static int xenvif_start_xmit(struct sk_buff *skb, struct net_device *dev) { struct xenvif *vif = netdev_priv(dev); struct xenvif_queue *queue = NULL; - unsigned int num_queues = vif->num_queues; + unsigned int num_queues; u16 index; struct xenvif_rx_cb *cb; BUG_ON(skb->dev != dev); - /* Drop the packet if queues are not set up */ + /* Drop the packet if queues are not set up. + * This handler should be called inside an RCU read section + * so we don't need to enter it here explicitly. + */ + num_queues = READ_ONCE(vif->num_queues); if (num_queues < 1) goto drop; @@ -222,18 +226,18 @@ static struct net_device_stats *xenvif_get_stats(struct net_device *dev) { struct xenvif *vif = netdev_priv(dev); struct xenvif_queue *queue = NULL; + unsigned int num_queues; u64 rx_bytes = 0; u64 rx_packets = 0; u64 tx_bytes = 0; u64 tx_packets = 0; unsigned int index; - spin_lock(&vif->lock); - if (vif->queues == NULL) - goto out; + rcu_read_lock(); + num_queues = READ_ONCE(vif->num_queues); /* Aggregate tx and rx stats from each queue */ - for (index = 0; index < vif->num_queues; ++index) { + for (index = 0; index < num_queues; ++index) { queue = &vif->queues[index]; rx_bytes += queue->stats.rx_bytes; rx_packets += queue->stats.rx_packets; @@ -241,8 +245,7 @@ static struct net_device_stats *xenvif_get_stats(struct net_device *dev) tx_packets += queue->stats.tx_packets; } -out: - spin_unlock(&vif->lock); + rcu_read_unlock(); vif->dev->stats.rx_bytes = rx_bytes; vif->dev->stats.rx_packets = rx_packets; @@ -378,10 +381,13 @@ static void xenvif_get_ethtool_stats(struct net_device *dev, struct ethtool_stats *stats, u64 * data) { struct xenvif *vif = netdev_priv(dev); - unsigned int num_queues = vif->num_queues; + unsigned int num_queues; int i; unsigned int queue_index; + rcu_read_lock(); + num_queues = READ_ONCE(vif->num_queues); + for (i = 0; i < ARRAY_SIZE(xenvif_stats); i++) { unsigned long accum = 0; for (queue_index = 0; queue_index < num_queues; ++queue_index) { @@ -390,6 +396,8 @@ static void xenvif_get_ethtool_stats(struct net_device *dev, } data[i] = accum; } + + rcu_read_unlock(); } static void xenvif_get_strings(struct net_device *dev, u32 stringset, u8 * data) |