[PATCH -next] bnx2: Use netif_carrier_off() to prevent timeout.

[PATCH -next] bnx2: Use netif_carrier_off() to prevent timeout.

[Michael Chan]

Based on original patch from Stanislaw Gruszka <sgruszka@redhat.com>.

Using netif_carrier_off() is better than updating all the ->trans_start
on all the tx queues.

netif_carrier_off() needs to be called after bnx2_disable_int_sync()
to guarantee no race conditions with the serdes timers that can
modify the carrier state.

If the chip or phy is reset, carrier will turn back on when we get the
link interrupt.  If there is no reset, we need to turn carrier back on
in bnx2_netif_start().  Again, the phy_lock prevents race conditions with
the serdes timers.

Signed-off-by: Michael Chan <mchan@broadcom.com>
Signed-off-by: Matt Carlson <mcarlson@broadcom.com>
---
 drivers/net/bnx2.c |   14 +++++---------
 1 files changed, 5 insertions(+), 9 deletions(-)

diff --git a/drivers/net/bnx2.c b/drivers/net/bnx2.c
index ab0068c..188e356 100644
--- a/drivers/net/bnx2.c
+++ b/drivers/net/bnx2.c
@@ -656,19 +656,11 @@ bnx2_netif_stop(struct bnx2 *bp, bool stop_cnic)
 	if (stop_cnic)
 		bnx2_cnic_stop(bp);
 	if (netif_running(bp->dev)) {
-		int i;
-
 		bnx2_napi_disable(bp);
 		netif_tx_disable(bp->dev);
-		/* prevent tx timeout */
-		for (i = 0; i <  bp->dev->num_tx_queues; i++) {
-			struct netdev_queue *txq;
-
-			txq = netdev_get_tx_queue(bp->dev, i);
-			txq->trans_start = jiffies;
-		}
 	}
 	bnx2_disable_int_sync(bp);
+	netif_carrier_off(bp->dev);	/* prevent tx timeout */
 }
 
 static void
@@ -677,6 +669,10 @@ bnx2_netif_start(struct bnx2 *bp, bool start_cnic)
 	if (atomic_dec_and_test(&bp->intr_sem)) {
 		if (netif_running(bp->dev)) {
 			netif_tx_wake_all_queues(bp->dev);
+			spin_lock_bh(&bp->phy_lock);
+			if (bp->link_up)
+				netif_carrier_on(bp->dev);
+			spin_unlock_bh(&bp->phy_lock);
 			bnx2_napi_enable(bp);
 			bnx2_enable_int(bp);
 			if (start_cnic)
-- 
1.6.4.GIT

Re: [PATCH -next] bnx2: Use netif_carrier_off() to prevent timeout.

[David Miller]

From: "Michael Chan" <mchan@broadcom.com>
Date: Thu, 13 May 2010 07:48:35 -0700

> Based on original patch from Stanislaw Gruszka <sgruszka@redhat.com>.
> 
> Using netif_carrier_off() is better than updating all the ->trans_start
> on all the tx queues.
> 
> netif_carrier_off() needs to be called after bnx2_disable_int_sync()
> to guarantee no race conditions with the serdes timers that can
> modify the carrier state.
> 
> If the chip or phy is reset, carrier will turn back on when we get the
> link interrupt.  If there is no reset, we need to turn carrier back on
> in bnx2_netif_start().  Again, the phy_lock prevents race conditions with
> the serdes timers.
> 
> Signed-off-by: Michael Chan <mchan@broadcom.com>
> Signed-off-by: Matt Carlson <mcarlson@broadcom.com>

Applied, thanks.