From a292ca6efbc1f259ddfb9c902367f2588e0e8b0f Mon Sep 17 00:00:00 2001 From: Jeff Kirsher Date: Thu, 12 Jan 2006 16:51:30 -0800 Subject: [PATCH] [PATCH] e1000: Added copy break code Improves small packet performance with large amounts of reassembly being done in the stack. Signed-off-by: Jeff Kirsher Signed-off-by: Jesse Brandeburg Signed-off-by: John Ronciak Signed-off-by: Jeff Garzik --- drivers/net/e1000/e1000_main.c | 59 +++++++++++++++++++++++++++------- 1 file changed, 47 insertions(+), 12 deletions(-) diff --git a/drivers/net/e1000/e1000_main.c b/drivers/net/e1000/e1000_main.c index 8207db44b7..bef4d9d6f2 100644 --- a/drivers/net/e1000/e1000_main.c +++ b/drivers/net/e1000/e1000_main.c @@ -420,7 +420,8 @@ e1000_up(struct e1000_adapter *adapter) * next_to_use != next_to_clean */ for (i = 0; i < adapter->num_rx_queues; i++) { struct e1000_rx_ring *ring = &adapter->rx_ring[i]; - adapter->alloc_rx_buf(adapter, ring, E1000_DESC_UNUSED(ring)); + adapter->alloc_rx_buf(adapter, ring, + E1000_DESC_UNUSED(ring)); } #ifdef CONFIG_PCI_MSI @@ -3567,23 +3568,26 @@ e1000_clean_rx_irq(struct e1000_adapter *adapter, uint32_t length; uint8_t last_byte; unsigned int i; - boolean_t cleaned = FALSE; int cleaned_count = 0; + boolean_t cleaned = FALSE, multi_descriptor = FALSE; i = rx_ring->next_to_clean; rx_desc = E1000_RX_DESC(*rx_ring, i); while(rx_desc->status & E1000_RXD_STAT_DD) { buffer_info = &rx_ring->buffer_info[i]; + u8 status; #ifdef CONFIG_E1000_NAPI if(*work_done >= work_to_do) break; (*work_done)++; #endif - + status = rx_desc->status; cleaned = TRUE; cleaned_count++; - pci_unmap_single(pdev, buffer_info->dma, buffer_info->length, + pci_unmap_single(pdev, + buffer_info->dma, + buffer_info->length, PCI_DMA_FROMDEVICE); skb = buffer_info->skb; @@ -3602,7 +3606,8 @@ e1000_clean_rx_irq(struct e1000_adapter *adapter, if(TBI_ACCEPT(&adapter->hw, rx_desc->status, rx_desc->errors, length, last_byte)) { spin_lock_irqsave(&adapter->stats_lock, flags); - e1000_tbi_adjust_stats(&adapter->hw, &adapter->stats, + e1000_tbi_adjust_stats(&adapter->hw, + &adapter->stats, length, skb->data); spin_unlock_irqrestore(&adapter->stats_lock, flags); @@ -3613,17 +3618,40 @@ e1000_clean_rx_irq(struct e1000_adapter *adapter, } } - /* Good Receive */ - skb_put(skb, length - ETHERNET_FCS_SIZE); + /* code added for copybreak, this should improve + * performance for small packets with large amounts + * of reassembly being done in the stack */ +#define E1000_CB_LENGTH 256 + if ((length < E1000_CB_LENGTH) && + !rx_ring->rx_skb_top && + /* or maybe (status & E1000_RXD_STAT_EOP) && */ + !multi_descriptor) { + struct sk_buff *new_skb = + dev_alloc_skb(length + NET_IP_ALIGN); + if (new_skb) { + skb_reserve(new_skb, NET_IP_ALIGN); + new_skb->dev = netdev; + memcpy(new_skb->data - NET_IP_ALIGN, + skb->data - NET_IP_ALIGN, + length + NET_IP_ALIGN); + /* save the skb in buffer_info as good */ + buffer_info->skb = skb; + skb = new_skb; + skb_put(skb, length); + } + } + + /* end copybreak code */ /* Receive Checksum Offload */ - e1000_rx_checksum(adapter, (uint32_t)(rx_desc->status) | + e1000_rx_checksum(adapter, + (uint32_t)(status) | ((uint32_t)(rx_desc->errors) << 24), rx_desc->csum, skb); skb->protocol = eth_type_trans(skb, netdev); #ifdef CONFIG_E1000_NAPI if(unlikely(adapter->vlgrp && - (rx_desc->status & E1000_RXD_STAT_VP))) { + (status & E1000_RXD_STAT_VP))) { vlan_hwaccel_receive_skb(skb, adapter->vlgrp, le16_to_cpu(rx_desc->special) & E1000_RXD_SPC_VLAN_MASK); @@ -3817,7 +3845,7 @@ next_desc: static void e1000_alloc_rx_buffers(struct e1000_adapter *adapter, struct e1000_rx_ring *rx_ring, - int cleaned_count) + int cleaned_count) { struct net_device *netdev = adapter->netdev; struct pci_dev *pdev = adapter->pdev; @@ -3830,8 +3858,14 @@ e1000_alloc_rx_buffers(struct e1000_adapter *adapter, i = rx_ring->next_to_use; buffer_info = &rx_ring->buffer_info[i]; - while(!buffer_info->skb) { - skb = dev_alloc_skb(bufsz); + while (cleaned_count--) { + if (!(skb = buffer_info->skb)) + skb = dev_alloc_skb(bufsz); + else { + skb_trim(skb, 0); + goto map_skb; + } + if(unlikely(!skb)) { /* Better luck next round */ @@ -3872,6 +3906,7 @@ e1000_alloc_rx_buffers(struct e1000_adapter *adapter, buffer_info->skb = skb; buffer_info->length = adapter->rx_buffer_len; +map_skb: buffer_info->dma = pci_map_single(pdev, skb->data, adapter->rx_buffer_len, -- 2.39.5