From ba53e6b4878e07411826312c59bfe49561594b6e Mon Sep 17 00:00:00 2001 From: Dhananjay Phadke Date: Mon, 17 Mar 2008 19:59:50 -0700 Subject: [PATCH] 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.h | 14 +--- drivers/net/netxen/netxen_nic_ethtool.c | 2 - drivers/net/netxen/netxen_nic_init.c | 89 +++++------------------ drivers/net/netxen/netxen_nic_main.c | 95 ++++++------------------- 4 files changed, 43 insertions(+), 157 deletions(-) diff --git a/drivers/net/netxen/netxen_nic.h b/drivers/net/netxen/netxen_nic.h index 8b6546ccb47b..070421b9e4f9 100644 --- a/drivers/net/netxen/netxen_nic.h +++ b/drivers/net/netxen/netxen_nic.h @@ -85,7 +85,7 @@ (sizeof(struct netxen_cmd_buffer) * adapter->max_tx_desc_count) #define RCV_BUFFSIZE \ (sizeof(struct netxen_rx_buffer) * rcv_desc->max_rx_desc_count) -#define find_diff_among(a,b,range) ((a)<=(b)?((b)-(a)):((b)+(range)-(a))) +#define find_diff_among(a,b,range) ((a)<(b)?((b)-(a)):((b)+(range)-(a))) #define NETXEN_NETDEV_STATUS 0x1 #define NETXEN_RCV_PRODUCER_OFFSET 0 @@ -204,7 +204,7 @@ enum { ? RCV_DESC_LRO : \ (RCV_DESC_NORMAL))) -#define MAX_CMD_DESCRIPTORS 1024 +#define MAX_CMD_DESCRIPTORS 4096 #define MAX_RCV_DESCRIPTORS 16384 #define MAX_CMD_DESCRIPTORS_HOST (MAX_CMD_DESCRIPTORS / 4) #define MAX_RCV_DESCRIPTORS_1G (MAX_RCV_DESCRIPTORS / 4) @@ -824,9 +824,7 @@ struct netxen_adapter_stats { u64 uphcong; u64 upmcong; u64 updunno; - u64 skbfreed; u64 txdropped; - u64 txnullskb; u64 csummed; u64 no_rcv; u64 rxbytes; @@ -888,8 +886,6 @@ struct netxen_adapter { int mtu; int portnum; - spinlock_t tx_lock; - spinlock_t lock; struct work_struct watchdog_task; struct timer_list watchdog_timer; struct work_struct tx_timeout_task; @@ -898,16 +894,12 @@ struct netxen_adapter { u32 cmd_producer; __le32 *cmd_consumer; - u32 last_cmd_consumer; + u32 max_tx_desc_count; u32 max_rx_desc_count; u32 max_jumbo_rx_desc_count; u32 max_lro_rx_desc_count; - /* Num of instances active on cmd buffer ring */ - u32 proc_cmd_buf_counter; - - u32 num_threads, total_threads; /*Use to keep track of xmit threads */ u32 flags; u32 irq; diff --git a/drivers/net/netxen/netxen_nic_ethtool.c b/drivers/net/netxen/netxen_nic_ethtool.c index 7a876f4b8db2..d324ea3bc7ba 100644 --- a/drivers/net/netxen/netxen_nic_ethtool.c +++ b/drivers/net/netxen/netxen_nic_ethtool.c @@ -70,9 +70,7 @@ static const struct netxen_nic_stats netxen_nic_gstrings_stats[] = { {"uphcong", NETXEN_NIC_STAT(stats.uphcong)}, {"upmcong", NETXEN_NIC_STAT(stats.upmcong)}, {"updunno", NETXEN_NIC_STAT(stats.updunno)}, - {"skb_freed", NETXEN_NIC_STAT(stats.skbfreed)}, {"tx_dropped", NETXEN_NIC_STAT(stats.txdropped)}, - {"tx_null_skb", NETXEN_NIC_STAT(stats.txnullskb)}, {"csummed", NETXEN_NIC_STAT(stats.csummed)}, {"no_rcv", NETXEN_NIC_STAT(stats.no_rcv)}, {"rx_bytes", NETXEN_NIC_STAT(stats.rxbytes)}, diff --git a/drivers/net/netxen/netxen_nic_init.c b/drivers/net/netxen/netxen_nic_init.c index 64fc18d4afb6..fe646187aa86 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); } diff --git a/drivers/net/netxen/netxen_nic_main.c b/drivers/net/netxen/netxen_nic_main.c index 95955204ef59..dc4d593217c9 100644 --- a/drivers/net/netxen/netxen_nic_main.c +++ b/drivers/net/netxen/netxen_nic_main.c @@ -317,7 +317,6 @@ netxen_nic_probe(struct pci_dev *pdev, const struct pci_device_id *ent) adapter->ahw.pdev = pdev; adapter->ahw.pci_func = pci_func_id; - spin_lock_init(&adapter->tx_lock); /* remap phys address */ mem_base = pci_resource_start(pdev, 0); /* 0 is for BAR 0 */ @@ -533,7 +532,6 @@ netxen_nic_probe(struct pci_dev *pdev, const struct pci_device_id *ent) adapter->watchdog_timer.data = (unsigned long)adapter; INIT_WORK(&adapter->watchdog_task, netxen_watchdog_task); adapter->ahw.pdev = pdev; - adapter->proc_cmd_buf_counter = 0; adapter->ahw.revision_id = pdev->revision; /* make sure Window == 1 */ @@ -952,41 +950,17 @@ static int netxen_nic_xmit_frame(struct sk_buff *skb, struct net_device *netdev) struct netxen_skb_frag *buffrag; unsigned int i; - u32 producer = 0; + u32 producer, consumer; u32 saved_producer = 0; struct cmd_desc_type0 *hwdesc; int k; struct netxen_cmd_buffer *pbuf = NULL; - static int dropped_packet = 0; int frag_count; - u32 local_producer = 0; - u32 max_tx_desc_count = 0; - u32 last_cmd_consumer = 0; int no_of_desc; + u32 num_txd = adapter->max_tx_desc_count; - adapter->stats.xmitcalled++; frag_count = skb_shinfo(skb)->nr_frags + 1; - if (unlikely(skb->len <= 0)) { - dev_kfree_skb_any(skb); - adapter->stats.badskblen++; - return NETDEV_TX_OK; - } - - if (frag_count > MAX_BUFFERS_PER_CMD) { - printk("%s: %s netxen_nic_xmit_frame: frag_count (%d) " - "too large, can handle only %d frags\n", - netxen_nic_driver_name, netdev->name, - frag_count, MAX_BUFFERS_PER_CMD); - adapter->stats.txdropped++; - if ((++dropped_packet & 0xff) == 0xff) - printk("%s: %s droppped packets = %d\n", - netxen_nic_driver_name, netdev->name, - dropped_packet); - - return NETDEV_TX_OK; - } - /* There 4 fragments per descriptor */ no_of_desc = (frag_count + 3) >> 2; if (netdev->features & NETIF_F_TSO) { @@ -1001,27 +975,16 @@ static int netxen_nic_xmit_frame(struct sk_buff *skb, struct net_device *netdev) } } - spin_lock_bh(&adapter->tx_lock); - if (adapter->total_threads >= MAX_XMIT_PRODUCERS) { - goto out_requeue; + producer = adapter->cmd_producer; + smp_mb(); + consumer = adapter->last_cmd_consumer; + if ((no_of_desc+2) > find_diff_among(producer, consumer, num_txd)) { + netif_stop_queue(netdev); + smp_mb(); + return NETDEV_TX_BUSY; } - local_producer = adapter->cmd_producer; - k = adapter->cmd_producer; - max_tx_desc_count = adapter->max_tx_desc_count; - last_cmd_consumer = adapter->last_cmd_consumer; - if ((k + no_of_desc) >= - ((last_cmd_consumer <= k) ? last_cmd_consumer + max_tx_desc_count : - last_cmd_consumer)) { - goto out_requeue; - } - k = get_index_range(k, max_tx_desc_count, no_of_desc); - adapter->cmd_producer = k; - adapter->total_threads++; - adapter->num_threads++; - spin_unlock_bh(&adapter->tx_lock); /* Copy the descriptors into the hardware */ - producer = local_producer; saved_producer = producer; hwdesc = &hw->cmd_desc_head[producer]; memset(hwdesc, 0, sizeof(struct cmd_desc_type0)); @@ -1061,8 +1024,7 @@ static int netxen_nic_xmit_frame(struct sk_buff *skb, struct net_device *netdev) /* move to next desc. if there is a need */ if ((i & 0x3) == 0) { k = 0; - producer = get_next_index(producer, - adapter->max_tx_desc_count); + producer = get_next_index(producer, num_txd); hwdesc = &hw->cmd_desc_head[producer]; memset(hwdesc, 0, sizeof(struct cmd_desc_type0)); pbuf = &adapter->cmd_buf_arr[producer]; @@ -1080,7 +1042,6 @@ static int netxen_nic_xmit_frame(struct sk_buff *skb, struct net_device *netdev) buffrag->dma = temp_dma; buffrag->length = temp_len; - DPRINTK(INFO, "for loop. i=%d k=%d\n", i, k); switch (k) { case 0: hwdesc->buffer1_length = cpu_to_le16(temp_len); @@ -1101,7 +1062,7 @@ static int netxen_nic_xmit_frame(struct sk_buff *skb, struct net_device *netdev) } frag++; } - producer = get_next_index(producer, adapter->max_tx_desc_count); + producer = get_next_index(producer, num_txd); /* might change opcode to TX_TCP_LSO */ netxen_tso_check(adapter, &hw->cmd_desc_head[saved_producer], skb); @@ -1128,7 +1089,7 @@ static int netxen_nic_xmit_frame(struct sk_buff *skb, struct net_device *netdev) /* copy the first 64 bytes */ memcpy(((void *)hwdesc) + 2, (void *)(skb->data), first_hdr_len); - producer = get_next_index(producer, max_tx_desc_count); + producer = get_next_index(producer, num_txd); if (more_hdr) { hwdesc = &hw->cmd_desc_head[producer]; @@ -1141,35 +1102,19 @@ static int netxen_nic_xmit_frame(struct sk_buff *skb, struct net_device *netdev) hwdesc, (hdr_len - first_hdr_len)); - producer = get_next_index(producer, max_tx_desc_count); + producer = get_next_index(producer, num_txd); } } - spin_lock_bh(&adapter->tx_lock); + adapter->cmd_producer = producer; adapter->stats.txbytes += skb->len; - /* Code to update the adapter considering how many producer threads - are currently working */ - if ((--adapter->num_threads) == 0) { - /* This is the last thread */ - u32 crb_producer = adapter->cmd_producer; - netxen_nic_update_cmd_producer(adapter, crb_producer); - wmb(); - adapter->total_threads = 0; - } + netxen_nic_update_cmd_producer(adapter, adapter->cmd_producer); - adapter->stats.xmitfinished++; + adapter->stats.xmitcalled++; netdev->trans_start = jiffies; - spin_unlock_bh(&adapter->tx_lock); return NETDEV_TX_OK; - -out_requeue: - netif_stop_queue(netdev); - adapter->flags |= NETXEN_NETDEV_STATUS; - - spin_unlock_bh(&adapter->tx_lock); - return NETDEV_TX_BUSY; } static void netxen_watchdog(unsigned long v) @@ -1194,9 +1139,13 @@ static void netxen_tx_timeout_task(struct work_struct *work) printk(KERN_ERR "%s %s: transmit timeout, resetting.\n", netxen_nic_driver_name, adapter->netdev->name); - netxen_nic_close(adapter->netdev); - netxen_nic_open(adapter->netdev); + netxen_nic_disable_int(adapter); + napi_disable(&adapter->napi); + adapter->netdev->trans_start = jiffies; + + napi_enable(&adapter->napi); + netxen_nic_enable_int(adapter); netif_wake_queue(adapter->netdev); } -- GitLab