Subject: Re: [REGRESSION] 2.6.24-rc7: e1000: Detected Tx Unit Hang

From: Badalian Vyacheslav <[email-masked]>
Date: Mon, 21 Jan 2008 09:54:43 +0300

Hello. Its work, thanks for resend it!
Sorry, i understand that patch 53e52c729cc169db82a6105fac7a166e10c2ec36 
("[NET]: Make ->poll() breakout consistent in Intel ethernet drivers.") 
have regression and rollback it, i not see your patch.
Sorry again.

Thanks!
> From: Badalian Vyacheslav <[email-masked]>
> Date: Wed, 16 Jan 2008 12:02:28 +0300
>
>   
>> Also have regression after apply patch.
>>     
>
> BTW, if you are using the e1000e driver then this initial
> patch will not work.
>
> My more recent patch posting for this problem, will.
>
> I include it again below for you:
>
> [NET]: Fix TX timeout regression in Intel drivers.
>
> This fixes a regression added by changeset
> 53e52c729cc169db82a6105fac7a166e10c2ec36 ("[NET]: Make ->poll()
> breakout consistent in Intel ethernet drivers.")
>
> As pointed out by Jesse Brandeburg, for three of the drivers edited
> above there is breakout logic in the *_clean_tx_irq() code to prevent
> running TX reclaim forever.  If this occurs, we have to elide NAPI
> poll completion or else those TX events will never be serviced.
>
> Signed-off-by: David S. Miller <[email-masked]>
>
> diff --git a/drivers/net/e1000/e1000_main.c b/drivers/net/e1000/e1000_main.c
> index 13d57b0..0c9a6f7 100644
> --- a/drivers/net/e1000/e1000_main.c
> +++ b/drivers/net/e1000/e1000_main.c
> @@ -3919,7 +3919,7 @@ e1000_clean(struct napi_struct *napi, int budget)
>  {
>  	struct e1000_adapter *adapter = container_of(napi, struct e1000_adapter, napi);
>  	struct net_device *poll_dev = adapter->netdev;
> -	int work_done = 0;
> +	int tx_cleaned = 0, work_done = 0;
>  
>  	/* Must NOT use netdev_priv macro here. */
>  	adapter = poll_dev->priv;
> @@ -3929,14 +3929,17 @@ e1000_clean(struct napi_struct *napi, int budget)
>  	 * simultaneously.  A failure obtaining the lock means
>  	 * tx_ring[0] is currently being cleaned anyway. */
>  	if (spin_trylock(&adapter->tx_queue_lock)) {
> -		e1000_clean_tx_irq(adapter,
> -				   &adapter->tx_ring[0]);
> +		tx_cleaned = e1000_clean_tx_irq(adapter,
> +						&adapter->tx_ring[0]);
>  		spin_unlock(&adapter->tx_queue_lock);
>  	}
>  
>  	adapter->clean_rx(adapter, &adapter->rx_ring[0],
>  	                  &work_done, budget);
>  
> +	if (tx_cleaned)
> +		work_done = budget;
> +
>  	/* If budget not fully consumed, exit the polling mode */
>  	if (work_done < budget) {
>  		if (likely(adapter->itr_setting & 3))
> diff --git a/drivers/net/e1000e/netdev.c b/drivers/net/e1000e/netdev.c
> index 4a6fc74..2ab3bfb 100644
> --- a/drivers/net/e1000e/netdev.c
> +++ b/drivers/net/e1000e/netdev.c
> @@ -1384,7 +1384,7 @@ static int e1000_clean(struct napi_struct *napi, int budget)
>  {
>  	struct e1000_adapter *adapter = container_of(napi, struct e1000_adapter, napi);
>  	struct net_device *poll_dev = adapter->netdev;
> -	int work_done = 0;
> +	int tx_cleaned = 0, work_done = 0;
>  
>  	/* Must NOT use netdev_priv macro here. */
>  	adapter = poll_dev->priv;
> @@ -1394,12 +1394,15 @@ static int e1000_clean(struct napi_struct *napi, int budget)
>  	 * simultaneously.  A failure obtaining the lock means
>  	 * tx_ring is currently being cleaned anyway. */
>  	if (spin_trylock(&adapter->tx_queue_lock)) {
> -		e1000_clean_tx_irq(adapter);
> +		tx_cleaned = e1000_clean_tx_irq(adapter);
>  		spin_unlock(&adapter->tx_queue_lock);
>  	}
>  
>  	adapter->clean_rx(adapter, &work_done, budget);
>  
> +	if (tx_cleaned)
> +		work_done = budget;
> +
>  	/* If budget not fully consumed, exit the polling mode */
>  	if (work_done < budget) {
>  		if (adapter->itr_setting & 3)
> diff --git a/drivers/net/ixgbe/ixgbe_main.c b/drivers/net/ixgbe/ixgbe_main.c
> index a564916..de3f45e 100644
> --- a/drivers/net/ixgbe/ixgbe_main.c
> +++ b/drivers/net/ixgbe/ixgbe_main.c
> @@ -1468,13 +1468,16 @@ static int ixgbe_clean(struct napi_struct *napi, int budget)
>  	struct ixgbe_adapter *adapter = container_of(napi,
>  					struct ixgbe_adapter, napi);
>  	struct net_device *netdev = adapter->netdev;
> -	int work_done = 0;
> +	int tx_cleaned = 0, work_done = 0;
>  
>  	/* In non-MSIX case, there is no multi-Tx/Rx queue */
> -	ixgbe_clean_tx_irq(adapter, adapter->tx_ring);
> +	tx_cleaned = ixgbe_clean_tx_irq(adapter, adapter->tx_ring);
>  	ixgbe_clean_rx_irq(adapter, &adapter->rx_ring[0], &work_done,
>  			   budget);
>  
> +	if (tx_cleaned)
> +		work_done = budget;
> +
>  	/* If budget not fully consumed, exit the polling mode */
>  	if (work_done < budget) {
>  		netif_rx_complete(netdev, napi);
>
>