summaryrefslogtreecommitdiff
diff options
context:
space:
mode:
authorEric Dumazet <edumazet@google.com>2012-05-14 09:26:06 +0000
committerDavid S. Miller <davem@davemloft.net>2012-05-15 13:41:43 -0400
commit3ab77bf271e6a41512e366dfa5110edb981ed1d3 (patch)
treed3ff26916d49bba577ea29fc58fe4f3319366056
parent4e6304b8420aba5311ba21fd68dab2924ae4d91a (diff)
pch_gbe: fix transmit races
Andy reported pch_gbe triggered "NETDEV WATCHDOG" errors. May 11 11:06:09 kontron kernel: WARNING: at net/sched/sch_generic.c:261 dev_watchdog+0x1ec/0x200() (Not tainted) May 11 11:06:09 kontron kernel: Hardware name: N/A May 11 11:06:09 kontron kernel: NETDEV WATCHDOG: eth0 (pch_gbe): transmit queue 0 timed out It seems pch_gbe has a racy tx path (races with TX completion path) Remove tx_queue_lock lock since it has no purpose, we must use tx_lock instead. Signed-off-by: Eric Dumazet <edumazet@google.com> Reported-by: Andy Cress <andy.cress@us.kontron.com> Tested-by: Andy Cress <andy.cress@us.kontron.com> Signed-off-by: David S. Miller <davem@davemloft.net>
-rw-r--r--drivers/net/ethernet/oki-semi/pch_gbe/pch_gbe.h2
-rw-r--r--drivers/net/ethernet/oki-semi/pch_gbe/pch_gbe_main.c25
2 files changed, 11 insertions, 16 deletions
diff --git a/drivers/net/ethernet/oki-semi/pch_gbe/pch_gbe.h b/drivers/net/ethernet/oki-semi/pch_gbe/pch_gbe.h
index dd14915f54bb..ba781747d174 100644
--- a/drivers/net/ethernet/oki-semi/pch_gbe/pch_gbe.h
+++ b/drivers/net/ethernet/oki-semi/pch_gbe/pch_gbe.h
@@ -584,7 +584,6 @@ struct pch_gbe_hw_stats {
/**
* struct pch_gbe_adapter - board specific private data structure
* @stats_lock: Spinlock structure for status
- * @tx_queue_lock: Spinlock structure for transmit
* @ethtool_lock: Spinlock structure for ethtool
* @irq_sem: Semaphore for interrupt
* @netdev: Pointer of network device structure
@@ -609,7 +608,6 @@ struct pch_gbe_hw_stats {
struct pch_gbe_adapter {
spinlock_t stats_lock;
- spinlock_t tx_queue_lock;
spinlock_t ethtool_lock;
atomic_t irq_sem;
struct net_device *netdev;
diff --git a/drivers/net/ethernet/oki-semi/pch_gbe/pch_gbe_main.c b/drivers/net/ethernet/oki-semi/pch_gbe/pch_gbe_main.c
index 8035e5ff6e06..1e38d502a062 100644
--- a/drivers/net/ethernet/oki-semi/pch_gbe/pch_gbe_main.c
+++ b/drivers/net/ethernet/oki-semi/pch_gbe/pch_gbe_main.c
@@ -640,14 +640,11 @@ static void pch_gbe_mac_set_pause_packet(struct pch_gbe_hw *hw)
*/
static int pch_gbe_alloc_queues(struct pch_gbe_adapter *adapter)
{
- int size;
-
- size = (int)sizeof(struct pch_gbe_tx_ring);
- adapter->tx_ring = kzalloc(size, GFP_KERNEL);
+ adapter->tx_ring = kzalloc(sizeof(*adapter->tx_ring), GFP_KERNEL);
if (!adapter->tx_ring)
return -ENOMEM;
- size = (int)sizeof(struct pch_gbe_rx_ring);
- adapter->rx_ring = kzalloc(size, GFP_KERNEL);
+
+ adapter->rx_ring = kzalloc(sizeof(*adapter->rx_ring), GFP_KERNEL);
if (!adapter->rx_ring) {
kfree(adapter->tx_ring);
return -ENOMEM;
@@ -1162,7 +1159,6 @@ static void pch_gbe_tx_queue(struct pch_gbe_adapter *adapter,
struct sk_buff *tmp_skb;
unsigned int frame_ctrl;
unsigned int ring_num;
- unsigned long flags;
/*-- Set frame control --*/
frame_ctrl = 0;
@@ -1211,14 +1207,14 @@ static void pch_gbe_tx_queue(struct pch_gbe_adapter *adapter,
}
}
}
- spin_lock_irqsave(&tx_ring->tx_lock, flags);
+
ring_num = tx_ring->next_to_use;
if (unlikely((ring_num + 1) == tx_ring->count))
tx_ring->next_to_use = 0;
else
tx_ring->next_to_use = ring_num + 1;
- spin_unlock_irqrestore(&tx_ring->tx_lock, flags);
+
buffer_info = &tx_ring->buffer_info[ring_num];
tmp_skb = buffer_info->skb;
@@ -1518,7 +1514,7 @@ pch_gbe_alloc_rx_buffers_pool(struct pch_gbe_adapter *adapter,
&rx_ring->rx_buff_pool_logic,
GFP_KERNEL);
if (!rx_ring->rx_buff_pool) {
- pr_err("Unable to allocate memory for the receive poll buffer\n");
+ pr_err("Unable to allocate memory for the receive pool buffer\n");
return -ENOMEM;
}
memset(rx_ring->rx_buff_pool, 0, size);
@@ -1637,15 +1633,17 @@ pch_gbe_clean_tx(struct pch_gbe_adapter *adapter,
pr_debug("called pch_gbe_unmap_and_free_tx_resource() %d count\n",
cleaned_count);
/* Recover from running out of Tx resources in xmit_frame */
+ spin_lock(&tx_ring->tx_lock);
if (unlikely(cleaned && (netif_queue_stopped(adapter->netdev)))) {
netif_wake_queue(adapter->netdev);
adapter->stats.tx_restart_count++;
pr_debug("Tx wake queue\n");
}
- spin_lock(&adapter->tx_queue_lock);
+
tx_ring->next_to_clean = i;
- spin_unlock(&adapter->tx_queue_lock);
+
pr_debug("next_to_clean : %d\n", tx_ring->next_to_clean);
+ spin_unlock(&tx_ring->tx_lock);
return cleaned;
}
@@ -2037,7 +2035,6 @@ static int pch_gbe_sw_init(struct pch_gbe_adapter *adapter)
return -ENOMEM;
}
spin_lock_init(&adapter->hw.miim_lock);
- spin_lock_init(&adapter->tx_queue_lock);
spin_lock_init(&adapter->stats_lock);
spin_lock_init(&adapter->ethtool_lock);
atomic_set(&adapter->irq_sem, 0);
@@ -2142,10 +2139,10 @@ static int pch_gbe_xmit_frame(struct sk_buff *skb, struct net_device *netdev)
tx_ring->next_to_use, tx_ring->next_to_clean);
return NETDEV_TX_BUSY;
}
- spin_unlock_irqrestore(&tx_ring->tx_lock, flags);
/* CRC,ITAG no support */
pch_gbe_tx_queue(adapter, tx_ring, skb);
+ spin_unlock_irqrestore(&tx_ring->tx_lock, flags);
return NETDEV_TX_OK;
}