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 <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/drivers/net/sundance.c b/drivers/net/sundance.c
index 27d69aa..4283cc5 100644
--- a/drivers/net/sundance.c
+++ b/drivers/net/sundance.c
@@ -365,7 +365,6 @@
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 @@
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 @@
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 @@
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 @@
dev->stats.rx_bytes += ioread16(ioaddr + RxOctetsLow);
dev->stats.rx_bytes += ioread16(ioaddr + RxOctetsHigh) << 16;
+ spin_unlock_irqrestore(&np->statlock, flags);
+
return &dev->stats;
}