From 7b738b55b2ec0e95a5030037c45b3c312e385789 Mon Sep 17 00:00:00 2001 From: Eric Dumazet Date: Sat, 9 Oct 2010 02:17:01 +0000 Subject: sundance: get_stats proper locking sundance get_stats() should not be run concurrently, add a lock to avoid potential losses. Note: Remove unused rx_lock field Signed-off-by: Eric Dumazet Signed-off-by: David S. Miller --- drivers/net/sundance.c | 10 ++++++---- 1 file changed, 6 insertions(+), 4 deletions(-) diff --git a/drivers/net/sundance.c b/drivers/net/sundance.c index 27d69aaba486..4283cc52a8c9 100644 --- a/drivers/net/sundance.c +++ b/drivers/net/sundance.c @@ -365,7 +365,6 @@ struct netdev_private { struct timer_list timer; /* Media monitoring timer. */ /* Frequently used values: keep some adjacent for cache effect. */ spinlock_t lock; - spinlock_t rx_lock; /* Group with Tx control cache line. */ int msg_enable; int chip_id; unsigned int cur_rx, dirty_rx; /* Producer/consumer ring indices */ @@ -390,6 +389,7 @@ struct netdev_private { unsigned char phys[MII_CNT]; /* MII device addresses, only first one used. */ struct pci_dev *pci_dev; void __iomem *base; + spinlock_t statlock; }; /* The station address location in the EEPROM. */ @@ -514,6 +514,7 @@ static int __devinit sundance_probe1 (struct pci_dev *pdev, np->chip_id = chip_idx; np->msg_enable = (1 << debug) - 1; spin_lock_init(&np->lock); + spin_lock_init(&np->statlock); tasklet_init(&np->rx_tasklet, rx_poll, (unsigned long)dev); tasklet_init(&np->tx_tasklet, tx_poll, (unsigned long)dev); @@ -1486,10 +1487,9 @@ static struct net_device_stats *get_stats(struct net_device *dev) struct netdev_private *np = netdev_priv(dev); void __iomem *ioaddr = np->base; int i; + unsigned long flags; - /* We should lock this segment of code for SMP eventually, although - the vulnerability window is very small and statistics are - non-critical. */ + spin_lock_irqsave(&np->statlock, flags); /* The chip only need report frame silently dropped. */ dev->stats.rx_missed_errors += ioread8(ioaddr + RxMissed); dev->stats.tx_packets += ioread16(ioaddr + TxFramesOK); @@ -1506,6 +1506,8 @@ static struct net_device_stats *get_stats(struct net_device *dev) dev->stats.rx_bytes += ioread16(ioaddr + RxOctetsLow); dev->stats.rx_bytes += ioread16(ioaddr + RxOctetsHigh) << 16; + spin_unlock_irqrestore(&np->statlock, flags); + return &dev->stats; } -- cgit v1.2.3