mlx4_en: Fix a kernel panic when waking tx queue

When the transmit queue gets full we enable interrupts for TX completions
There was a race that we handled the TX queue both from the interrupt context
and from the transmit function. Using "spin_trylock_irq()" ensures this
doesn't happen.

Signed-off-by: Yevgeny Petrilin <yevgenyp@mellanox.co.il>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Yevgeny Petrilin 2009-05-25 20:57:21 +00:00 committed by David S. Miller
parent e8573758d5
commit 465440d272

View file

@ -426,7 +426,7 @@ void mlx4_en_poll_tx_cq(unsigned long data)
INC_PERF_COUNTER(priv->pstats.tx_poll);
if (!spin_trylock(&ring->comp_lock)) {
if (!spin_trylock_irq(&ring->comp_lock)) {
mod_timer(&cq->timer, jiffies + MLX4_EN_TX_POLL_TIMEOUT);
return;
}
@ -439,7 +439,7 @@ void mlx4_en_poll_tx_cq(unsigned long data)
if (inflight && priv->port_up)
mod_timer(&cq->timer, jiffies + MLX4_EN_TX_POLL_TIMEOUT);
spin_unlock(&ring->comp_lock);
spin_unlock_irq(&ring->comp_lock);
}
static struct mlx4_en_tx_desc *mlx4_en_bounce_to_desc(struct mlx4_en_priv *priv,
@ -482,9 +482,9 @@ static inline void mlx4_en_xmit_poll(struct mlx4_en_priv *priv, int tx_ind)
/* Poll the CQ every mlx4_en_TX_MODER_POLL packets */
if ((++ring->poll_cnt & (MLX4_EN_TX_POLL_MODER - 1)) == 0)
if (spin_trylock(&ring->comp_lock)) {
if (spin_trylock_irq(&ring->comp_lock)) {
mlx4_en_process_tx_cq(priv->dev, cq);
spin_unlock(&ring->comp_lock);
spin_unlock_irq(&ring->comp_lock);
}
}