[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 <jeffrey.t.kirsher@intel.com>
Signed-off-by: Jesse Brandeburg <jesse.brandeburg@intel.com>
Signed-off-by: John Ronciak <john.ronciak@intel.com>
Signed-off-by: Jeff Garzik <jgarzik@pobox.com>
diff --git a/drivers/net/e1000/e1000_main.c b/drivers/net/e1000/e1000_main.c
index 8207db4..bef4d9d 100644
--- a/drivers/net/e1000/e1000_main.c
+++ b/drivers/net/e1000/e1000_main.c
@@ -420,7 +420,8 @@
* 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 @@
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 @@
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 @@
}
}
- /* 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 @@
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 @@
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 @@
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,