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ixbge: remove TX lock and redo TX accounting.

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This ports Herbert Xu's "maybe_stop_tx" code and removes the tx_lock
which is not needed.

Signed-off-by: Ayyappan Veeraiyan <ayyappan.veeraiyan@intel.com>
Signed-off-by: Auke Kok <auke-jan.h.kok@intel.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
This commit is contained in:
Ayyappan Veeraiyan 2008-02-01 15:58:49 -08:00 committed by Jeff Garzik
parent d4f80882ee
commit e092be60b2
2 changed files with 76 additions and 36 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

2
drivers/net/ixgbe/ixgbe.h
View File

@ -136,8 +136,6 @@ struct ixgbe_ring {
u16 head;
u16 tail;
/* To protect race between sender and clean_tx_irq */
spinlock_t tx_lock;
struct ixgbe_queue_stats stats;

110
drivers/net/ixgbe/ixgbe_main.c
View File

@ -165,6 +165,15 @@ static inline bool ixgbe_check_tx_hang(struct ixgbe_adapter *adapter,
return false;
}
#define IXGBE_MAX_TXD_PWR 14
#define IXGBE_MAX_DATA_PER_TXD (1 << IXGBE_MAX_TXD_PWR)
/* Tx Descriptors needed, worst case */
#define TXD_USE_COUNT(S) (((S) >> IXGBE_MAX_TXD_PWR) + \
(((S) & (IXGBE_MAX_DATA_PER_TXD - 1)) ? 1 : 0))
#define DESC_NEEDED (TXD_USE_COUNT(IXGBE_MAX_DATA_PER_TXD) /* skb->data */ + \
MAX_SKB_FRAGS * TXD_USE_COUNT(PAGE_SIZE) + 1) /* for context */
/**
* ixgbe_clean_tx_irq - Reclaim resources after transmit completes
* @adapter: board private structure
@ -177,18 +186,34 @@ static bool ixgbe_clean_tx_irq(struct ixgbe_adapter *adapter,
struct ixgbe_tx_buffer *tx_buffer_info;
unsigned int i, eop;
bool cleaned = false;
int count = 0;
unsigned int total_tx_bytes = 0, total_tx_packets = 0;
i = tx_ring->next_to_clean;
eop = tx_ring->tx_buffer_info[i].next_to_watch;
eop_desc = IXGBE_TX_DESC_ADV(*tx_ring, eop);
while (eop_desc->wb.status & cpu_to_le32(IXGBE_TXD_STAT_DD)) {
for (cleaned = false; !cleaned;) {
cleaned = false;
while (!cleaned) {
tx_desc = IXGBE_TX_DESC_ADV(*tx_ring, i);
tx_buffer_info = &tx_ring->tx_buffer_info[i];
cleaned = (i == eop);
tx_ring->stats.bytes += tx_buffer_info->length;
if (cleaned) {
struct sk_buff *skb = tx_buffer_info->skb;
#ifdef NETIF_F_TSO
unsigned int segs, bytecount;
segs = skb_shinfo(skb)->gso_segs ?: 1;
/* multiply data chunks by size of headers */
bytecount = ((segs - 1) * skb_headlen(skb)) +
skb->len;
total_tx_packets += segs;
total_tx_bytes += bytecount;
#else
total_tx_packets++;
total_tx_bytes += skb->len;
#endif
}
ixgbe_unmap_and_free_tx_resource(adapter,
tx_buffer_info);
tx_desc->wb.status = 0;
@ -204,29 +229,34 @@ static bool ixgbe_clean_tx_irq(struct ixgbe_adapter *adapter,
eop_desc = IXGBE_TX_DESC_ADV(*tx_ring, eop);
/* weight of a sort for tx, avoid endless transmit cleanup */
if (count++ >= tx_ring->work_limit)
if (total_tx_packets >= tx_ring->work_limit)
break;
}
tx_ring->next_to_clean = i;
#define TX_WAKE_THRESHOLD 32
spin_lock(&tx_ring->tx_lock);
if (cleaned && netif_carrier_ok(netdev) &&
(IXGBE_DESC_UNUSED(tx_ring) >= TX_WAKE_THRESHOLD) &&
!test_bit(__IXGBE_DOWN, &adapter->state))
netif_wake_queue(netdev);
spin_unlock(&tx_ring->tx_lock);
#define TX_WAKE_THRESHOLD (DESC_NEEDED * 2)
if (total_tx_packets && netif_carrier_ok(netdev) &&
(IXGBE_DESC_UNUSED(tx_ring) >= TX_WAKE_THRESHOLD)) {
/* Make sure that anybody stopping the queue after this
* sees the new next_to_clean.
*/
smp_mb();
if (netif_queue_stopped(netdev) &&
!test_bit(__IXGBE_DOWN, &adapter->state)) {
netif_wake_queue(netdev);
adapter->restart_queue++;
}
}
if (adapter->detect_tx_hung)
if (ixgbe_check_tx_hang(adapter, tx_ring, eop, eop_desc))
netif_stop_queue(netdev);
if (count >= tx_ring->work_limit)
if (total_tx_packets >= tx_ring->work_limit)
IXGBE_WRITE_REG(&adapter->hw, IXGBE_EICS, tx_ring->eims_value);
cleaned = total_tx_packets ? true : false;
return cleaned;
}
@ -1646,7 +1676,6 @@ int ixgbe_setup_tx_resources(struct ixgbe_adapter *adapter,
txdr->next_to_use = 0;
txdr->next_to_clean = 0;
txdr->work_limit = txdr->count;
spin_lock_init(&txdr->tx_lock);
return 0;
}
@ -2086,15 +2115,6 @@ static void ixgbe_watchdog(unsigned long data)
round_jiffies(jiffies + 2 * HZ));
}
#define IXGBE_MAX_TXD_PWR 14
#define IXGBE_MAX_DATA_PER_TXD (1 << IXGBE_MAX_TXD_PWR)
/* Tx Descriptors needed, worst case */
#define TXD_USE_COUNT(S) (((S) >> IXGBE_MAX_TXD_PWR) + \
(((S) & (IXGBE_MAX_DATA_PER_TXD - 1)) ? 1 : 0))
#define DESC_NEEDED (TXD_USE_COUNT(IXGBE_MAX_DATA_PER_TXD) /* skb->data */ + \
MAX_SKB_FRAGS * TXD_USE_COUNT(PAGE_SIZE) + 1) /* for context */
static int ixgbe_tso(struct ixgbe_adapter *adapter,
struct ixgbe_ring *tx_ring, struct sk_buff *skb,
u32 tx_flags, u8 *hdr_len)
@ -2366,6 +2386,37 @@ static void ixgbe_tx_queue(struct ixgbe_adapter *adapter,
writel(i, adapter->hw.hw_addr + tx_ring->tail);
}
static int __ixgbe_maybe_stop_tx(struct net_device *netdev,
struct ixgbe_ring *tx_ring, int size)
{
struct ixgbe_adapter *adapter = netdev_priv(netdev);
netif_stop_queue(netdev);
/* Herbert's original patch had:
* smp_mb__after_netif_stop_queue();
* but since that doesn't exist yet, just open code it. */
smp_mb();
/* We need to check again in a case another CPU has just
* made room available. */
if (likely(IXGBE_DESC_UNUSED(tx_ring) < size))
return -EBUSY;
/* A reprieve! - use start_queue because it doesn't call schedule */
netif_wake_queue(netdev);
++adapter->restart_queue;
return 0;
}
static int ixgbe_maybe_stop_tx(struct net_device *netdev,
struct ixgbe_ring *tx_ring, int size)
{
if (likely(IXGBE_DESC_UNUSED(tx_ring) >= size))
return 0;
return __ixgbe_maybe_stop_tx(netdev, tx_ring, size);
}
static int ixgbe_xmit_frame(struct sk_buff *skb, struct net_device *netdev)
{
struct ixgbe_adapter *adapter = netdev_priv(netdev);
@ -2373,7 +2424,6 @@ static int ixgbe_xmit_frame(struct sk_buff *skb, struct net_device *netdev)
unsigned int len = skb->len;
unsigned int first;
unsigned int tx_flags = 0;
unsigned long flags = 0;
u8 hdr_len;
int tso;
unsigned int mss = 0;
@ -2399,14 +2449,10 @@ static int ixgbe_xmit_frame(struct sk_buff *skb, struct net_device *netdev)
for (f = 0; f < nr_frags; f++)
count += TXD_USE_COUNT(skb_shinfo(skb)->frags[f].size);
spin_lock_irqsave(&tx_ring->tx_lock, flags);
if (IXGBE_DESC_UNUSED(tx_ring) < (count + 2)) {
if (ixgbe_maybe_stop_tx(netdev, tx_ring, count)) {
adapter->tx_busy++;
netif_stop_queue(netdev);
spin_unlock_irqrestore(&tx_ring->tx_lock, flags);
return NETDEV_TX_BUSY;
}
spin_unlock_irqrestore(&tx_ring->tx_lock, flags);
if (adapter->vlgrp && vlan_tx_tag_present(skb)) {
tx_flags |= IXGBE_TX_FLAGS_VLAN;
tx_flags |= (vlan_tx_tag_get(skb) << IXGBE_TX_FLAGS_VLAN_SHIFT);
@ -2433,11 +2479,7 @@ static int ixgbe_xmit_frame(struct sk_buff *skb, struct net_device *netdev)
netdev->trans_start = jiffies;
spin_lock_irqsave(&tx_ring->tx_lock, flags);
/* Make sure there is space in the ring for the next send. */
if (IXGBE_DESC_UNUSED(tx_ring) < DESC_NEEDED)
netif_stop_queue(netdev);
spin_unlock_irqrestore(&tx_ring->tx_lock, flags);
ixgbe_maybe_stop_tx(netdev, tx_ring, DESC_NEEDED);
return NETDEV_TX_OK;
}