[PATCH] skge: Rx buffer optimization

Optimize the receive buffer management code to replenish the
buffers immediately (like tg3).

Signed-off-by: Stephen Hemmminger <shemminger@osdl.org>
This commit is contained in:
Stephen Hemminger 2005-06-27 11:33:15 -07:00 committed by Jeff Garzik
parent d25f5a6774
commit 19a33d4e6b
2 changed files with 164 additions and 104 deletions

View file

@ -49,6 +49,8 @@
#define DEFAULT_RX_RING_SIZE 512
#define MAX_TX_RING_SIZE 1024
#define MAX_RX_RING_SIZE 4096
#define RX_COPY_THRESHOLD 128
#define RX_BUF_SIZE 1536
#define PHY_RETRIES 1000
#define ETH_JUMBO_MTU 9000
#define TX_WATCHDOG (5 * HZ)
@ -746,6 +748,7 @@ static int skge_ring_alloc(struct skge_ring *ring, void *vaddr, u64 base)
for (i = 0, e = ring->start, d = vaddr; i < ring->count; i++, e++, d++) {
e->desc = d;
e->skb = NULL;
if (i == ring->count - 1) {
e->next = ring->start;
d->next_offset = base;
@ -759,24 +762,23 @@ static int skge_ring_alloc(struct skge_ring *ring, void *vaddr, u64 base)
return 0;
}
/* Setup buffer for receiving */
static inline int skge_rx_alloc(struct skge_port *skge,
struct skge_element *e)
static struct sk_buff *skge_rx_alloc(struct net_device *dev, unsigned int size)
{
unsigned long bufsize = skge->netdev->mtu + ETH_HLEN; /* VLAN? */
struct skge_rx_desc *rd = e->desc;
struct sk_buff *skb;
u64 map;
struct sk_buff *skb = dev_alloc_skb(size);
skb = dev_alloc_skb(bufsize + NET_IP_ALIGN);
if (unlikely(!skb)) {
printk(KERN_DEBUG PFX "%s: out of memory for receive\n",
skge->netdev->name);
return -ENOMEM;
if (likely(skb)) {
skb->dev = dev;
skb_reserve(skb, NET_IP_ALIGN);
}
return skb;
}
skb->dev = skge->netdev;
skb_reserve(skb, NET_IP_ALIGN);
/* Allocate and setup a new buffer for receiving */
static void skge_rx_setup(struct skge_port *skge, struct skge_element *e,
struct sk_buff *skb, unsigned int bufsize)
{
struct skge_rx_desc *rd = e->desc;
u64 map;
map = pci_map_single(skge->hw->pdev, skb->data, bufsize,
PCI_DMA_FROMDEVICE);
@ -794,55 +796,69 @@ static inline int skge_rx_alloc(struct skge_port *skge,
rd->control = BMU_OWN | BMU_STF | BMU_IRQ_EOF | BMU_TCP_CHECK | bufsize;
pci_unmap_addr_set(e, mapaddr, map);
pci_unmap_len_set(e, maplen, bufsize);
return 0;
}
/* Free all unused buffers in receive ring, assumes receiver stopped */
/* Resume receiving using existing skb,
* Note: DMA address is not changed by chip.
* MTU not changed while receiver active.
*/
static void skge_rx_reuse(struct skge_element *e, unsigned int size)
{
struct skge_rx_desc *rd = e->desc;
rd->csum2 = 0;
rd->csum2_start = ETH_HLEN;
wmb();
rd->control = BMU_OWN | BMU_STF | BMU_IRQ_EOF | BMU_TCP_CHECK | size;
}
/* Free all buffers in receive ring, assumes receiver stopped */
static void skge_rx_clean(struct skge_port *skge)
{
struct skge_hw *hw = skge->hw;
struct skge_ring *ring = &skge->rx_ring;
struct skge_element *e;
for (e = ring->to_clean; e != ring->to_use; e = e->next) {
e = ring->start;
do {
struct skge_rx_desc *rd = e->desc;
rd->control = 0;
pci_unmap_single(hw->pdev,
pci_unmap_addr(e, mapaddr),
pci_unmap_len(e, maplen),
PCI_DMA_FROMDEVICE);
dev_kfree_skb(e->skb);
e->skb = NULL;
}
ring->to_clean = e;
if (e->skb) {
pci_unmap_single(hw->pdev,
pci_unmap_addr(e, mapaddr),
pci_unmap_len(e, maplen),
PCI_DMA_FROMDEVICE);
dev_kfree_skb(e->skb);
e->skb = NULL;
}
} while ((e = e->next) != ring->start);
}
/* Allocate buffers for receive ring
* For receive: to_use is refill location
* to_clean is next received frame.
*
* if (to_use == to_clean)
* then ring all frames in ring need buffers
* if (to_use->next == to_clean)
* then ring all frames in ring have buffers
* For receive: to_clean is next received frame.
*/
static int skge_rx_fill(struct skge_port *skge)
{
struct skge_ring *ring = &skge->rx_ring;
struct skge_element *e;
int ret = 0;
unsigned int bufsize = skge->rx_buf_size;
for (e = ring->to_use; e->next != ring->to_clean; e = e->next) {
if (skge_rx_alloc(skge, e)) {
ret = 1;
break;
}
e = ring->start;
do {
struct sk_buff *skb = skge_rx_alloc(skge->netdev, bufsize);
}
ring->to_use = e;
if (!skb)
return -ENOMEM;
return ret;
skge_rx_setup(skge, e, skb, bufsize);
} while ( (e = e->next) != ring->start);
ring->to_clean = ring->start;
return 0;
}
static void skge_link_up(struct skge_port *skge)
@ -2048,6 +2064,12 @@ static int skge_up(struct net_device *dev)
if (netif_msg_ifup(skge))
printk(KERN_INFO PFX "%s: enabling interface\n", dev->name);
if (dev->mtu > RX_BUF_SIZE)
skge->rx_buf_size = dev->mtu + ETH_HLEN + NET_IP_ALIGN;
else
skge->rx_buf_size = RX_BUF_SIZE;
rx_size = skge->rx_ring.count * sizeof(struct skge_rx_desc);
tx_size = skge->tx_ring.count * sizeof(struct skge_tx_desc);
skge->mem_size = tx_size + rx_size;
@ -2060,7 +2082,8 @@ static int skge_up(struct net_device *dev)
if ((err = skge_ring_alloc(&skge->rx_ring, skge->mem, skge->dma)))
goto free_pci_mem;
if (skge_rx_fill(skge))
err = skge_rx_fill(skge);
if (err)
goto free_rx_ring;
if ((err = skge_ring_alloc(&skge->tx_ring, skge->mem + rx_size,
@ -2284,6 +2307,7 @@ static int skge_xmit_frame(struct sk_buff *skb, struct net_device *dev)
static inline void skge_tx_free(struct skge_hw *hw, struct skge_element *e)
{
/* This ring element can be skb or fragment */
if (e->skb) {
pci_unmap_single(hw->pdev,
pci_unmap_addr(e, mapaddr),
@ -2328,16 +2352,17 @@ static void skge_tx_timeout(struct net_device *dev)
static int skge_change_mtu(struct net_device *dev, int new_mtu)
{
int err = 0;
int running = netif_running(dev);
if (new_mtu < ETH_ZLEN || new_mtu > ETH_JUMBO_MTU)
return -EINVAL;
dev->mtu = new_mtu;
if (netif_running(dev)) {
if (running)
skge_down(dev);
dev->mtu = new_mtu;
if (running)
skge_up(dev);
}
return err;
}
@ -2436,28 +2461,76 @@ static void skge_rx_error(struct skge_port *skge, int slot,
printk(KERN_DEBUG PFX "%s: rx err, slot %d control 0x%x status 0x%x\n",
skge->netdev->name, slot, control, status);
if ((control & (BMU_EOF|BMU_STF)) != (BMU_STF|BMU_EOF)
|| (control & BMU_BBC) > skge->netdev->mtu + VLAN_ETH_HLEN)
if ((control & (BMU_EOF|BMU_STF)) != (BMU_STF|BMU_EOF))
skge->net_stats.rx_length_errors++;
else {
if (skge->hw->chip_id == CHIP_ID_GENESIS) {
if (status & (XMR_FS_RUNT|XMR_FS_LNG_ERR))
skge->net_stats.rx_length_errors++;
if (status & XMR_FS_FRA_ERR)
skge->net_stats.rx_frame_errors++;
if (status & XMR_FS_FCS_ERR)
skge->net_stats.rx_crc_errors++;
} else {
if (status & (GMR_FS_LONG_ERR|GMR_FS_UN_SIZE))
skge->net_stats.rx_length_errors++;
if (status & GMR_FS_FRAGMENT)
skge->net_stats.rx_frame_errors++;
if (status & GMR_FS_CRC_ERR)
skge->net_stats.rx_crc_errors++;
}
else if (skge->hw->chip_id == CHIP_ID_GENESIS) {
if (status & (XMR_FS_RUNT|XMR_FS_LNG_ERR))
skge->net_stats.rx_length_errors++;
if (status & XMR_FS_FRA_ERR)
skge->net_stats.rx_frame_errors++;
if (status & XMR_FS_FCS_ERR)
skge->net_stats.rx_crc_errors++;
} else {
if (status & (GMR_FS_LONG_ERR|GMR_FS_UN_SIZE))
skge->net_stats.rx_length_errors++;
if (status & GMR_FS_FRAGMENT)
skge->net_stats.rx_frame_errors++;
if (status & GMR_FS_CRC_ERR)
skge->net_stats.rx_crc_errors++;
}
}
/* Get receive buffer from descriptor.
* Handles copy of small buffers and reallocation failures
*/
static inline struct sk_buff *skge_rx_get(struct skge_port *skge,
struct skge_element *e,
unsigned int len)
{
struct sk_buff *nskb, *skb;
if (len < RX_COPY_THRESHOLD) {
nskb = skge_rx_alloc(skge->netdev, len + NET_IP_ALIGN);
if (unlikely(!nskb))
return NULL;
pci_dma_sync_single_for_cpu(skge->hw->pdev,
pci_unmap_addr(e, mapaddr),
len, PCI_DMA_FROMDEVICE);
memcpy(nskb->data, e->skb->data, len);
pci_dma_sync_single_for_device(skge->hw->pdev,
pci_unmap_addr(e, mapaddr),
len, PCI_DMA_FROMDEVICE);
if (skge->rx_csum) {
struct skge_rx_desc *rd = e->desc;
nskb->csum = le16_to_cpu(rd->csum2);
nskb->ip_summed = CHECKSUM_HW;
}
skge_rx_reuse(e, skge->rx_buf_size);
return nskb;
} else {
nskb = skge_rx_alloc(skge->netdev, skge->rx_buf_size);
if (unlikely(!nskb))
return NULL;
pci_unmap_single(skge->hw->pdev,
pci_unmap_addr(e, mapaddr),
pci_unmap_len(e, maplen),
PCI_DMA_FROMDEVICE);
skb = e->skb;
if (skge->rx_csum) {
struct skge_rx_desc *rd = e->desc;
skb->csum = le16_to_cpu(rd->csum2);
skb->ip_summed = CHECKSUM_HW;
}
skge_rx_setup(skge, e, nskb, skge->rx_buf_size);
return skb;
}
}
static int skge_poll(struct net_device *dev, int *budget)
{
struct skge_port *skge = netdev_priv(dev);
@ -2466,14 +2539,12 @@ static int skge_poll(struct net_device *dev, int *budget)
struct skge_element *e;
unsigned int to_do = min(dev->quota, *budget);
unsigned int work_done = 0;
int done;
pr_debug("skge_poll\n");
for (e = ring->to_clean; e != ring->to_use && work_done < to_do;
e = e->next) {
for (e = ring->to_clean; work_done < to_do; e = e->next) {
struct skge_rx_desc *rd = e->desc;
struct sk_buff *skb = e->skb;
struct sk_buff *skb;
u32 control, len, status;
rmb();
@ -2482,19 +2553,12 @@ static int skge_poll(struct net_device *dev, int *budget)
break;
len = control & BMU_BBC;
e->skb = NULL;
pci_unmap_single(hw->pdev,
pci_unmap_addr(e, mapaddr),
pci_unmap_len(e, maplen),
PCI_DMA_FROMDEVICE);
status = rd->status;
if ((control & (BMU_EOF|BMU_STF)) != (BMU_STF|BMU_EOF)
|| len > dev->mtu + VLAN_ETH_HLEN
|| bad_phy_status(hw, status)) {
if (unlikely((control & (BMU_EOF|BMU_STF)) != (BMU_STF|BMU_EOF)
|| bad_phy_status(hw, status))) {
skge_rx_error(skge, e - ring->start, control, status);
dev_kfree_skb(skb);
skge_rx_reuse(e, skge->rx_buf_size);
continue;
}
@ -2502,42 +2566,37 @@ static int skge_poll(struct net_device *dev, int *budget)
printk(KERN_DEBUG PFX "%s: rx slot %td status 0x%x len %d\n",
dev->name, e - ring->start, rd->status, len);
skb_put(skb, len);
skb->protocol = eth_type_trans(skb, dev);
skb = skge_rx_get(skge, e, len);
if (likely(skb)) {
skb_put(skb, len);
skb->protocol = eth_type_trans(skb, dev);
if (skge->rx_csum) {
skb->csum = le16_to_cpu(rd->csum2);
skb->ip_summed = CHECKSUM_HW;
}
dev->last_rx = jiffies;
netif_receive_skb(skb);
dev->last_rx = jiffies;
netif_receive_skb(skb);
++work_done;
++work_done;
} else
skge_rx_reuse(e, skge->rx_buf_size);
}
ring->to_clean = e;
*budget -= work_done;
dev->quota -= work_done;
done = work_done < to_do;
if (skge_rx_fill(skge))
done = 0;
/* restart receiver */
wmb();
skge_write8(hw, Q_ADDR(rxqaddr[skge->port], Q_CSR),
CSR_START | CSR_IRQ_CL_F);
if (done) {
local_irq_disable();
__netif_rx_complete(dev);
hw->intr_mask |= portirqmask[skge->port];
skge_write32(hw, B0_IMSK, hw->intr_mask);
local_irq_enable();
}
*budget -= work_done;
dev->quota -= work_done;
return !done;
if (work_done >= to_do)
return 1; /* not done */
local_irq_disable();
__netif_rx_complete(dev);
hw->intr_mask |= portirqmask[skge->port];
skge_write32(hw, B0_IMSK, hw->intr_mask);
local_irq_enable();
return 0;
}
static inline void skge_tx_intr(struct net_device *dev)

View file

@ -2503,6 +2503,7 @@ struct skge_port {
void *mem; /* PCI memory for rings */
dma_addr_t dma;
unsigned long mem_size;
unsigned int rx_buf_size;
struct timer_list led_blink;
};