From d3d9e484b2ca502c87156b69fa6b8f8fd5fa18a0 Mon Sep 17 00:00:00 2001 From: Auke Kok Date: Fri, 14 Jul 2006 16:14:23 -0700 Subject: [PATCH] e1000: Redo netpoll fix to address community concerns The original suggested fix for netpoll was found to be racy on SMP kernels. While it is highly unlikely that this race would ever be seen in the real world due to current netpoll usage models, we implemented this updated fix to address concerns. Signed-off-by: Mitch Williams Signed-off-by: Auke Kok --- drivers/net/e1000/e1000_main.c | 37 ++++++++++++++-------------------- 1 file changed, 15 insertions(+), 22 deletions(-) diff --git a/drivers/net/e1000/e1000_main.c b/drivers/net/e1000/e1000_main.c index 6d3d41934503..1c6bcad5b910 100644 --- a/drivers/net/e1000/e1000_main.c +++ b/drivers/net/e1000/e1000_main.c @@ -3387,8 +3387,8 @@ e1000_intr(int irq, void *data, struct pt_regs *regs) E1000_WRITE_REG(hw, IMC, ~0); E1000_WRITE_FLUSH(hw); } - if (likely(netif_rx_schedule_prep(&adapter->polling_netdev[0]))) - __netif_rx_schedule(&adapter->polling_netdev[0]); + if (likely(netif_rx_schedule_prep(netdev))) + __netif_rx_schedule(netdev); else e1000_irq_enable(adapter); #else @@ -3431,34 +3431,26 @@ e1000_clean(struct net_device *poll_dev, int *budget) { struct e1000_adapter *adapter; int work_to_do = min(*budget, poll_dev->quota); - int tx_cleaned = 0, i = 0, work_done = 0; + int tx_cleaned = 0, work_done = 0; /* Must NOT use netdev_priv macro here. */ adapter = poll_dev->priv; /* Keep link state information with original netdev */ - if (!netif_carrier_ok(adapter->netdev)) + if (!netif_carrier_ok(poll_dev)) goto quit_polling; - while (poll_dev != &adapter->polling_netdev[i]) { - i++; - BUG_ON(i == adapter->num_rx_queues); + /* e1000_clean is called per-cpu. This lock protects + * tx_ring[0] from being cleaned by multiple cpus + * simultaneously. A failure obtaining the lock means + * tx_ring[0] is currently being cleaned anyway. */ + if (spin_trylock(&adapter->tx_queue_lock)) { + tx_cleaned = e1000_clean_tx_irq(adapter, + &adapter->tx_ring[0]); + spin_unlock(&adapter->tx_queue_lock); } - if (likely(adapter->num_tx_queues == 1)) { - /* e1000_clean is called per-cpu. This lock protects - * tx_ring[0] from being cleaned by multiple cpus - * simultaneously. A failure obtaining the lock means - * tx_ring[0] is currently being cleaned anyway. */ - if (spin_trylock(&adapter->tx_queue_lock)) { - tx_cleaned = e1000_clean_tx_irq(adapter, - &adapter->tx_ring[0]); - spin_unlock(&adapter->tx_queue_lock); - } - } else - tx_cleaned = e1000_clean_tx_irq(adapter, &adapter->tx_ring[i]); - - adapter->clean_rx(adapter, &adapter->rx_ring[i], + adapter->clean_rx(adapter, &adapter->rx_ring[0], &work_done, work_to_do); *budget -= work_done; @@ -3466,7 +3458,7 @@ e1000_clean(struct net_device *poll_dev, int *budget) /* If no Tx and not enough Rx work done, exit the polling mode */ if ((!tx_cleaned && (work_done == 0)) || - !netif_running(adapter->netdev)) { + !netif_running(poll_dev)) { quit_polling: netif_rx_complete(poll_dev); e1000_irq_enable(adapter); @@ -4752,6 +4744,7 @@ static void e1000_netpoll(struct net_device *netdev) { struct e1000_adapter *adapter = netdev_priv(netdev); + disable_irq(adapter->pdev->irq); e1000_intr(adapter->pdev->irq, netdev, NULL); e1000_clean_tx_irq(adapter, adapter->tx_ring);