Subject: Re: [PATCH] [-MM, FIX V3] e1000e: incorporate napi_struct changes from net-2.6.24.git

From: "Kok, Auke" <[email-masked]>
Date: Fri, 07 Sep 2007 17:30:59 -0700

Auke Kok wrote:
> This incorporates the new napi_struct changes into e1000e. Included
> bugfix for ifdown hang from Krishna Kumar for e1000.
> 
> Disabling polling is no longer needed at init time, so remove
> napi_disable() call from _probe().

david,

while testing this patch I noticed that the poll routine is now called 100% of 
the time, and since I'm not doing much different than before, I suspec that 
something in the new napi code is staying in polling mode forever? Since e1000e 
is pretty much the same code as e1000, I doubt the problem is there, but you can 
probably tell better. ideas?

Auke

> 
> Signed-off-by: Auke Kok <[email-masked]>
> ---
> 
>  drivers/net/e1000e/e1000.h  |    2 ++
>  drivers/net/e1000e/netdev.c |   39 ++++++++++++++++-----------------------
>  2 files changed, 18 insertions(+), 23 deletions(-)
> 
> diff --git a/drivers/net/e1000e/e1000.h b/drivers/net/e1000e/e1000.h
> index c57e35a..d2499bb 100644
> --- a/drivers/net/e1000e/e1000.h
> +++ b/drivers/net/e1000e/e1000.h
> @@ -187,6 +187,8 @@ struct e1000_adapter {
>  	struct e1000_ring *tx_ring /* One per active queue */
>  						____cacheline_aligned_in_smp;
>  
> +	struct napi_struct napi;
> +
>  	unsigned long tx_queue_len;
>  	unsigned int restart_queue;
>  	u32 txd_cmd;
> diff --git a/drivers/net/e1000e/netdev.c b/drivers/net/e1000e/netdev.c
> index 372da46..f8ec537 100644
> --- a/drivers/net/e1000e/netdev.c
> +++ b/drivers/net/e1000e/netdev.c
> @@ -1149,12 +1149,12 @@ static irqreturn_t e1000_intr_msi(int irq, void *data)
>  			mod_timer(&adapter->watchdog_timer, jiffies + 1);
>  	}
>  
> -	if (netif_rx_schedule_prep(netdev)) {
> +	if (netif_rx_schedule_prep(netdev, &adapter->napi)) {
>  		adapter->total_tx_bytes = 0;
>  		adapter->total_tx_packets = 0;
>  		adapter->total_rx_bytes = 0;
>  		adapter->total_rx_packets = 0;
> -		__netif_rx_schedule(netdev);
> +		__netif_rx_schedule(netdev, &adapter->napi);
>  	} else {
>  		atomic_dec(&adapter->irq_sem);
>  	}
> @@ -1212,12 +1212,12 @@ static irqreturn_t e1000_intr(int irq, void *data)
>  			mod_timer(&adapter->watchdog_timer, jiffies + 1);
>  	}
>  
> -	if (netif_rx_schedule_prep(netdev)) {
> +	if (netif_rx_schedule_prep(netdev, &adapter->napi)) {
>  		adapter->total_tx_bytes = 0;
>  		adapter->total_tx_packets = 0;
>  		adapter->total_rx_bytes = 0;
>  		adapter->total_rx_packets = 0;
> -		__netif_rx_schedule(netdev);
> +		__netif_rx_schedule(netdev, &adapter->napi);
>  	} else {
>  		atomic_dec(&adapter->irq_sem);
>  	}
> @@ -1662,10 +1662,10 @@ set_itr_now:
>   * e1000_clean - NAPI Rx polling callback
>   * @adapter: board private structure
>   **/
> -static int e1000_clean(struct net_device *poll_dev, int *budget)
> +static int e1000_clean(struct napi_struct *napi, int budget)
>  {
> -	struct e1000_adapter *adapter;
> -	int work_to_do = min(*budget, poll_dev->quota);
> +	struct e1000_adapter *adapter = container_of(napi, struct e1000_adapter, napi);
> +	struct net_device *poll_dev = adapter->netdev;
>  	int tx_cleaned = 0, work_done = 0;
>  
>  	/* Must NOT use netdev_priv macro here. */
> @@ -1684,25 +1684,20 @@ static int e1000_clean(struct net_device *poll_dev, int *budget)
>  		spin_unlock(&adapter->tx_queue_lock);
>  	}
>  
> -	adapter->clean_rx(adapter, &work_done, work_to_do);
> -	*budget -= work_done;
> -	poll_dev->quota -= work_done;
> +	adapter->clean_rx(adapter, &work_done, budget);
>  
>  	/* If no Tx and not enough Rx work done, exit the polling mode */
> -	if ((!tx_cleaned && (work_done == 0)) ||
> +	if ((tx_cleaned && (work_done < budget)) ||
>  	   !netif_running(poll_dev)) {
>  quit_polling:
>  		if (adapter->itr_setting & 3)
>  			e1000_set_itr(adapter);
> -		netif_rx_complete(poll_dev);
> -		if (test_bit(__E1000_DOWN, &adapter->state))
> -			atomic_dec(&adapter->irq_sem);
> -		else
> -			e1000_irq_enable(adapter);
> +		netif_rx_complete(poll_dev, napi);
> +		e1000_irq_enable(adapter);
>  		return 0;
>  	}
>  
> -	return 1;
> +	return work_done;
>  }
>  
>  static void e1000_vlan_rx_add_vid(struct net_device *netdev, u16 vid)
> @@ -2439,7 +2434,7 @@ int e1000e_up(struct e1000_adapter *adapter)
>  
>  	clear_bit(__E1000_DOWN, &adapter->state);
>  
> -	netif_poll_enable(adapter->netdev);
> +	napi_enable(&adapter->napi);
>  	e1000_irq_enable(adapter);
>  
>  	/* fire a link change interrupt to start the watchdog */
> @@ -2472,7 +2467,7 @@ void e1000e_down(struct e1000_adapter *adapter)
>  	e1e_flush();
>  	msleep(10);
>  
> -	netif_poll_disable(netdev);
> +	napi_disable(&adapter->napi);
>  	e1000_irq_disable(adapter);
>  
>  	del_timer_sync(&adapter->watchdog_timer);
> @@ -2605,7 +2600,7 @@ static int e1000_open(struct net_device *netdev)
>  	/* From here on the code is the same as e1000e_up() */
>  	clear_bit(__E1000_DOWN, &adapter->state);
>  
> -	netif_poll_enable(netdev);
> +	napi_enable(&adapter->napi);
>  
>  	e1000_irq_enable(adapter);
>  
> @@ -4090,8 +4085,7 @@ static int __devinit e1000_probe(struct pci_dev *pdev,
>  	e1000e_set_ethtool_ops(netdev);
>  	netdev->tx_timeout		= &e1000_tx_timeout;
>  	netdev->watchdog_timeo		= 5 * HZ;
> -	netdev->poll			= &e1000_clean;
> -	netdev->weight			= 64;
> +	netif_napi_add(netdev, &adapter->napi, e1000_clean, 64);
>  	netdev->vlan_rx_register	= e1000_vlan_rx_register;
>  	netdev->vlan_rx_add_vid		= e1000_vlan_rx_add_vid;
>  	netdev->vlan_rx_kill_vid	= e1000_vlan_rx_kill_vid;
> @@ -4260,7 +4254,6 @@ static int __devinit e1000_probe(struct pci_dev *pdev,
>  	/* tell the stack to leave us alone until e1000_open() is called */
>  	netif_carrier_off(netdev);
>  	netif_stop_queue(netdev);
> -	netif_poll_disable(netdev);
>  
>  	strcpy(netdev->name, "eth%d");
>  	err = register_netdev(netdev);
>