net: trans_start cleanups

Now that core network takes care of trans_start updates, dont do it
in drivers themselves, if possible. Drivers can avoid one cache miss
(on dev->trans_start) in their start_xmit() handler.

Exceptions are NETIF_F_LLTX drivers

Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

7 files changed, 3 insertions, 12 deletions

diff --git a/drivers/net/wan/dscc4.c b/drivers/net/wan/dscc4.c
index a4859f7..d45b08d 100644
--- a/drivers/net/wan/dscc4.c
+++ b/drivers/net/wan/dscc4.c
@@ -1175,8 +1175,6 @@ static netdev_tx_t dscc4_start_xmit(struct sk_buff *skb,
 	spin_unlock(&dpriv->lock);
 #endif
 
-	dev->trans_start = jiffies;
-
 	if (debug > 2)
 		dscc4_tx_print(dev, dpriv, "Xmit");
 	/* To be cleaned(unsigned int)/optimized. Later, ok ? */
diff --git a/drivers/net/wan/hd64570.c b/drivers/net/wan/hd64570.c
index 4dde2ea..a3ea27c 100644
--- a/drivers/net/wan/hd64570.c
+++ b/drivers/net/wan/hd64570.c
@@ -658,7 +658,6 @@ static netdev_tx_t sca_xmit(struct sk_buff *skb, struct net_device *dev)
 #endif
 	writew(len, &desc->len);
 	writeb(ST_TX_EOM, &desc->stat);
-	dev->trans_start = jiffies;
 
 	port->txin = next_desc(port, port->txin, 1);
 	sca_outw(desc_offset(port, port->txin, 1),
diff --git a/drivers/net/wan/hd64572.c b/drivers/net/wan/hd64572.c
index aad9ed4..ea476cb 100644
--- a/drivers/net/wan/hd64572.c
+++ b/drivers/net/wan/hd64572.c
@@ -585,7 +585,6 @@ static netdev_tx_t sca_xmit(struct sk_buff *skb, struct net_device *dev)
 
 	writew(len, &desc->len);
 	writeb(ST_TX_EOM, &desc->stat);
-	dev->trans_start = jiffies;
 
 	port->txin = (port->txin + 1) % card->tx_ring_buffers;
 	sca_outl(desc_offset(port, port->txin, 1),
diff --git a/drivers/net/wan/ixp4xx_hss.c b/drivers/net/wan/ixp4xx_hss.c
index 0c2cdde..88e3630 100644
--- a/drivers/net/wan/ixp4xx_hss.c
+++ b/drivers/net/wan/ixp4xx_hss.c
@@ -891,7 +891,6 @@ static int hss_hdlc_xmit(struct sk_buff *skb, struct net_device *dev)
 
 	wmb();
 	queue_put_desc(queue_ids[port->id].tx, tx_desc_phys(port, n), desc);
-	dev->trans_start = jiffies;
 
 	if (qmgr_stat_below_low_watermark(txreadyq)) { /* empty */
 #if DEBUG_TX
diff --git a/drivers/net/wan/lmc/lmc_main.c b/drivers/net/wan/lmc/lmc_main.c
index b278503..e2c6f7f 100644
--- a/drivers/net/wan/lmc/lmc_main.c
+++ b/drivers/net/wan/lmc/lmc_main.c
@@ -1506,8 +1506,6 @@ static netdev_tx_t lmc_start_xmit(struct sk_buff *skb,
     /* send now! */
     LMC_CSR_WRITE (sc, csr_txpoll, 0);
 
-    dev->trans_start = jiffies;
-
     spin_unlock_irqrestore(&sc->lmc_lock, flags);
 
     lmc_trace(dev, "lmc_start_xmit_out");
@@ -2103,7 +2101,7 @@ static void lmc_driver_timeout(struct net_device *dev)
     printk("%s: Xmitter busy|\n", dev->name);
 
     sc->extra_stats.tx_tbusy_calls++;
-    if (jiffies - dev->trans_start < TX_TIMEOUT)
+    if (jiffies - dev_trans_start(dev) < TX_TIMEOUT)
 	    goto bug_out;
 
     /*
@@ -2135,7 +2133,7 @@ static void lmc_driver_timeout(struct net_device *dev)
     sc->lmc_device->stats.tx_errors++;
     sc->extra_stats.tx_ProcTimeout++; /* -baz */
 
-    dev->trans_start = jiffies;
+    dev->trans_start = jiffies; /* prevent tx timeout */
 
 bug_out:
 
diff --git a/drivers/net/wan/pc300_drv.c b/drivers/net/wan/pc300_drv.c
index 17502d8..c6aa66e 100644
--- a/drivers/net/wan/pc300_drv.c
+++ b/drivers/net/wan/pc300_drv.c
@@ -1790,7 +1790,7 @@ static void cpc_tx_timeout(struct net_device *dev)
 			   cpc_readb(card->hw.falcbase + card->hw.cpld_reg2) &
 			   ~(CPLD_REG2_FALC_LED1 << (2 * ch)));
 	}
-	dev->trans_start = jiffies;
+	dev->trans_start = jiffies; /* prevent tx timeout */
 	CPC_UNLOCK(card, flags);
 	netif_wake_queue(dev);
 }
@@ -1849,7 +1849,6 @@ static int cpc_queue_xmit(struct sk_buff *skb, struct net_device *dev)
 	if (d->trace_on) {
 		cpc_trace(dev, skb, 'T');
 	}
-	dev->trans_start = jiffies;
 
 	/* Start transmission */
 	CPC_LOCK(card, flags);
diff --git a/drivers/net/wan/wanxl.c b/drivers/net/wan/wanxl.c
index 541c700..db73a7b 100644
--- a/drivers/net/wan/wanxl.c
+++ b/drivers/net/wan/wanxl.c
@@ -298,7 +298,6 @@ static netdev_tx_t wanxl_xmit(struct sk_buff *skb, struct net_device *dev)
 	desc->stat = PACKET_FULL;
 	writel(1 << (DOORBELL_TO_CARD_TX_0 + port->node),
 	       port->card->plx + PLX_DOORBELL_TO_CARD);
-	dev->trans_start = jiffies;
 
 	port->tx_out = (port->tx_out + 1) % TX_BUFFERS;