From b891a9023bc4fc639b31c234a705e7e51104cf22 Mon Sep 17 00:00:00 2001 From: Catalin Marinas Date: Mon, 20 Oct 2008 18:15:37 +0100 Subject: smc911x: Make the driver safer on SMP This patch extends the critical regions covered by lp->lock to make it safer on SMP. The main failure point was the smc911x_hard_start_xmit function being called from different CPUs. It was tested on the ARM SMP platforms. Signed-off-by: Catalin Marinas Signed-off-by: Jeff Garzik --- drivers/net/smc911x.c | 25 ++++++++----------------- 1 file changed, 8 insertions(+), 17 deletions(-) (limited to 'drivers') diff --git a/drivers/net/smc911x.c b/drivers/net/smc911x.c index 2c78229ad04b..f59c7772f344 100644 --- a/drivers/net/smc911x.c +++ b/drivers/net/smc911x.c @@ -155,23 +155,17 @@ static void PRINT_PKT(u_char *buf, int length) /* this enables an interrupt in the interrupt mask register */ #define SMC_ENABLE_INT(lp, x) do { \ unsigned int __mask; \ - unsigned long __flags; \ - spin_lock_irqsave(&lp->lock, __flags); \ __mask = SMC_GET_INT_EN((lp)); \ __mask |= (x); \ SMC_SET_INT_EN((lp), __mask); \ - spin_unlock_irqrestore(&lp->lock, __flags); \ } while (0) /* this disables an interrupt from the interrupt mask register */ #define SMC_DISABLE_INT(lp, x) do { \ unsigned int __mask; \ - unsigned long __flags; \ - spin_lock_irqsave(&lp->lock, __flags); \ __mask = SMC_GET_INT_EN((lp)); \ __mask &= ~(x); \ SMC_SET_INT_EN((lp), __mask); \ - spin_unlock_irqrestore(&lp->lock, __flags); \ } while (0) /* @@ -279,6 +273,8 @@ static void smc911x_enable(struct net_device *dev) DBG(SMC_DEBUG_FUNC, "%s: --> %s\n", dev->name, __func__); + spin_lock_irqsave(&lp->lock, flags); + SMC_SET_MAC_ADDR(lp, dev->dev_addr); /* Enable TX */ @@ -291,12 +287,10 @@ static void smc911x_enable(struct net_device *dev) SMC_SET_FIFO_TSL(lp, 64); SMC_SET_GPT_CFG(lp, GPT_CFG_TIMER_EN_ | 10000); - spin_lock_irqsave(&lp->lock, flags); SMC_GET_MAC_CR(lp, cr); cr |= MAC_CR_TXEN_ | MAC_CR_HBDIS_; SMC_SET_MAC_CR(lp, cr); SMC_SET_TX_CFG(lp, TX_CFG_TX_ON_); - spin_unlock_irqrestore(&lp->lock, flags); /* Add 2 byte padding to start of packets */ SMC_SET_RX_CFG(lp, (2<<8) & RX_CFG_RXDOFF_); @@ -305,9 +299,7 @@ static void smc911x_enable(struct net_device *dev) if (cr & MAC_CR_RXEN_) DBG(SMC_DEBUG_RX, "%s: Receiver already enabled\n", dev->name); - spin_lock_irqsave(&lp->lock, flags); SMC_SET_MAC_CR(lp, cr | MAC_CR_RXEN_); - spin_unlock_irqrestore(&lp->lock, flags); /* Interrupt on every received packet */ SMC_SET_FIFO_RSA(lp, 0x01); @@ -323,6 +315,8 @@ static void smc911x_enable(struct net_device *dev) mask|=INT_EN_RDFO_EN_; } SMC_ENABLE_INT(lp, mask); + + spin_unlock_irqrestore(&lp->lock, flags); } /* @@ -463,7 +457,6 @@ static void smc911x_hardware_send_pkt(struct net_device *dev) struct sk_buff *skb; unsigned int cmdA, cmdB, len; unsigned char *buf; - unsigned long flags; DBG(SMC_DEBUG_FUNC | SMC_DEBUG_TX, "%s: --> %s\n", dev->name, __func__); BUG_ON(lp->pending_tx_skb == NULL); @@ -508,11 +501,9 @@ static void smc911x_hardware_send_pkt(struct net_device *dev) dev->trans_start = jiffies; dev_kfree_skb(skb); #endif - spin_lock_irqsave(&lp->lock, flags); if (!lp->tx_throttle) { netif_wake_queue(dev); } - spin_unlock_irqrestore(&lp->lock, flags); SMC_ENABLE_INT(lp, INT_EN_TDFA_EN_ | INT_EN_TSFL_EN_); } @@ -531,6 +522,8 @@ static int smc911x_hard_start_xmit(struct sk_buff *skb, struct net_device *dev) DBG(SMC_DEBUG_FUNC | SMC_DEBUG_TX, "%s: --> %s\n", dev->name, __func__); + spin_lock_irqsave(&lp->lock, flags); + BUG_ON(lp->pending_tx_skb != NULL); free = SMC_GET_TX_FIFO_INF(lp) & TX_FIFO_INF_TDFREE_; @@ -540,12 +533,10 @@ static int smc911x_hard_start_xmit(struct sk_buff *skb, struct net_device *dev) if (free <= SMC911X_TX_FIFO_LOW_THRESHOLD) { DBG(SMC_DEBUG_TX, "%s: Disabling data flow due to low FIFO space (%d)\n", dev->name, free); - spin_lock_irqsave(&lp->lock, flags); /* Reenable when at least 1 packet of size MTU present */ SMC_SET_FIFO_TDA(lp, (SMC911X_TX_FIFO_LOW_THRESHOLD)/64); lp->tx_throttle = 1; netif_stop_queue(dev); - spin_unlock_irqrestore(&lp->lock, flags); } /* Drop packets when we run out of space in TX FIFO @@ -561,6 +552,7 @@ static int smc911x_hard_start_xmit(struct sk_buff *skb, struct net_device *dev) lp->pending_tx_skb = NULL; dev->stats.tx_errors++; dev->stats.tx_dropped++; + spin_unlock_irqrestore(&lp->lock, flags); dev_kfree_skb(skb); return 0; } @@ -570,7 +562,6 @@ static int smc911x_hard_start_xmit(struct sk_buff *skb, struct net_device *dev) /* If the DMA is already running then defer this packet Tx until * the DMA IRQ starts it */ - spin_lock_irqsave(&lp->lock, flags); if (lp->txdma_active) { DBG(SMC_DEBUG_TX | SMC_DEBUG_DMA, "%s: Tx DMA running, deferring packet\n", dev->name); lp->pending_tx_skb = skb; @@ -581,11 +572,11 @@ static int smc911x_hard_start_xmit(struct sk_buff *skb, struct net_device *dev) DBG(SMC_DEBUG_TX | SMC_DEBUG_DMA, "%s: Activating Tx DMA\n", dev->name); lp->txdma_active = 1; } - spin_unlock_irqrestore(&lp->lock, flags); } #endif lp->pending_tx_skb = skb; smc911x_hardware_send_pkt(dev); + spin_unlock_irqrestore(&lp->lock, flags); return 0; } -- cgit v1.2.3