From ba53e6b4878e07411826312c59bfe49561594b6e Mon Sep 17 00:00:00 2001 From: Dhananjay Phadke Date: Mon, 17 Mar 2008 19:59:50 -0700 Subject: netxen: remove low level tx lock o eliminate tx lock in netxen adapter struct, instead pound on netdev tx lock appropriately. o remove old "concurrent transmit" code that unnecessarily drops and reacquires tx lock in hard_xmit_frame(), this is already serialized the netdev xmit lock. o reduce scope of tx lock in tx cleanup. tx cleanup operates on different section of the ring than transmitting cpus and is guarded by producer and consumer indices. This fixes a race caused by rx softirq preemption on realtime kernels. Signed-off-by: Dhananjay Phadke Tested-by: Vernon Mauery Signed-off-by: Jeff Garzik --- drivers/net/netxen/netxen_nic_init.c | 89 ++++++++---------------------------- 1 file changed, 18 insertions(+), 71 deletions(-) (limited to 'drivers/net/netxen/netxen_nic_init.c') diff --git a/drivers/net/netxen/netxen_nic_init.c b/drivers/net/netxen/netxen_nic_init.c index 64fc18d4afb..fe646187aa8 100644 --- a/drivers/net/netxen/netxen_nic_init.c +++ b/drivers/net/netxen/netxen_nic_init.c @@ -1197,96 +1197,50 @@ u32 netxen_process_rcv_ring(struct netxen_adapter *adapter, int ctxid, int max) /* Process Command status ring */ int netxen_process_cmd_ring(struct netxen_adapter *adapter) { - u32 last_consumer; - u32 consumer; - int count1 = 0; - int count2 = 0; + u32 last_consumer, consumer; + int count = 0, i; struct netxen_cmd_buffer *buffer; - struct pci_dev *pdev; + struct pci_dev *pdev = adapter->pdev; + struct net_device *netdev = adapter->netdev; struct netxen_skb_frag *frag; - u32 i; - int done; + int done = 0; - spin_lock(&adapter->tx_lock); last_consumer = adapter->last_cmd_consumer; - DPRINTK(INFO, "procesing xmit complete\n"); - /* we assume in this case that there is only one port and that is - * port #1...changes need to be done in firmware to indicate port - * number as part of the descriptor. This way we will be able to get - * the netdev which is associated with that device. - */ - consumer = le32_to_cpu(*(adapter->cmd_consumer)); - if (last_consumer == consumer) { /* Ring is empty */ - DPRINTK(INFO, "last_consumer %d == consumer %d\n", - last_consumer, consumer); - spin_unlock(&adapter->tx_lock); - return 1; - } - - adapter->proc_cmd_buf_counter++; - /* - * Not needed - does not seem to be used anywhere. - * adapter->cmd_consumer = consumer; - */ - spin_unlock(&adapter->tx_lock); - while ((last_consumer != consumer) && (count1 < MAX_STATUS_HANDLE)) { + while (last_consumer != consumer) { buffer = &adapter->cmd_buf_arr[last_consumer]; - pdev = adapter->pdev; if (buffer->skb) { frag = &buffer->frag_array[0]; pci_unmap_single(pdev, frag->dma, frag->length, PCI_DMA_TODEVICE); frag->dma = 0ULL; for (i = 1; i < buffer->frag_count; i++) { - DPRINTK(INFO, "getting fragment no %d\n", i); frag++; /* Get the next frag */ pci_unmap_page(pdev, frag->dma, frag->length, PCI_DMA_TODEVICE); frag->dma = 0ULL; } - adapter->stats.skbfreed++; + adapter->stats.xmitfinished++; dev_kfree_skb_any(buffer->skb); buffer->skb = NULL; - } else if (adapter->proc_cmd_buf_counter == 1) { - adapter->stats.txnullskb++; - } - if (unlikely(netif_queue_stopped(adapter->netdev) - && netif_carrier_ok(adapter->netdev)) - && ((jiffies - adapter->netdev->trans_start) > - adapter->netdev->watchdog_timeo)) { - SCHEDULE_WORK(&adapter->tx_timeout_task); } last_consumer = get_next_index(last_consumer, adapter->max_tx_desc_count); - count1++; + if (++count >= MAX_STATUS_HANDLE) + break; } - count2 = 0; - spin_lock(&adapter->tx_lock); - if ((--adapter->proc_cmd_buf_counter) == 0) { + if (count) { adapter->last_cmd_consumer = last_consumer; - while ((adapter->last_cmd_consumer != consumer) - && (count2 < MAX_STATUS_HANDLE)) { - buffer = - &adapter->cmd_buf_arr[adapter->last_cmd_consumer]; - count2++; - if (buffer->skb) - break; - else - adapter->last_cmd_consumer = - get_next_index(adapter->last_cmd_consumer, - adapter->max_tx_desc_count); - } - } - if (count1 || count2) { - if (netif_queue_stopped(adapter->netdev) - && (adapter->flags & NETXEN_NETDEV_STATUS)) { - netif_wake_queue(adapter->netdev); - adapter->flags &= ~NETXEN_NETDEV_STATUS; + smp_mb(); + if (netif_queue_stopped(netdev) && netif_running(netdev)) { + netif_tx_lock(netdev); + netif_wake_queue(netdev); + smp_mb(); + netif_tx_unlock(netdev); } } /* @@ -1302,16 +1256,9 @@ int netxen_process_cmd_ring(struct netxen_adapter *adapter) * There is still a possible race condition and the host could miss an * interrupt. The card has to take care of this. */ - if (adapter->last_cmd_consumer == consumer && - (((adapter->cmd_producer + 1) % - adapter->max_tx_desc_count) == adapter->last_cmd_consumer)) { - consumer = le32_to_cpu(*(adapter->cmd_consumer)); - } - done = (adapter->last_cmd_consumer == consumer); + consumer = le32_to_cpu(*(adapter->cmd_consumer)); + done = (last_consumer == consumer); - spin_unlock(&adapter->tx_lock); - DPRINTK(INFO, "last consumer is %d in %s\n", last_consumer, - __FUNCTION__); return (done); } -- cgit v1.2.3-70-g09d2