From mboxrd@z Thu Jan  1 00:00:00 1970
From: Jarek Poplawski <jarkao2@gmail.com>
Subject: Re: [Bug #14925] sky2 panic under load
Date: Mon, 11 Jan 2010 23:31:26 +0100
Message-ID: <20100111223126.GA3369@del.dom.local>
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Cc: Mike McCormack <mikem@ring3k.org>,
	"Berck E. Nash" <flyboy@gmail.com>,
	"Rafael J. Wysocki" <rjw@sisk.pl>, netdev@vger.kernel.org
To: Stephen Hemminger <shemminger@vyatta.com>
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On Mon, Jan 11, 2010 at 08:45:04AM -0800, Stephen Hemminger wrote:
> On Mon, 11 Jan 2010 23:03:41 +0900
> Mike McCormack <mikem@ring3k.org> wrote:
> 
> > Perhaps only sky2_tx_done should wake the queue?
> > Does the patch below fix the problem too?
> > 
> > thanks,
> > 
> > Mike
> 
> The idea is good, but what if transmit queue was full (stopped),
> and TX FIFO gets stuck.  Then Transmit timeout happens and
> the reset logic clears the queue.  What will start the queue?
> 
> Something like this:
> -----------------------------------------------------------
> 
> 
> 
> --- a/drivers/net/sky2.c	2010-01-11 08:36:42.617426300 -0800
> +++ b/drivers/net/sky2.c	2010-01-11 08:42:51.295237661 -0800
> @@ -1843,9 +1843,6 @@ static void sky2_tx_complete(struct sky2
>  
>  	sky2->tx_cons = idx;
>  	smp_mb();
> -
> -	if (tx_avail(sky2) > MAX_SKB_TX_LE + 4)
> -		netif_wake_queue(dev);
>  }
>  
>  static void sky2_tx_reset(struct sky2_hw *hw, unsigned port)
> @@ -2416,8 +2413,12 @@ static inline void sky2_tx_done(struct n
>  {
>  	struct sky2_port *sky2 = netdev_priv(dev);
>  
> -	if (netif_running(dev))
> +	if (netif_running(dev) && netif_device_present(dev)) {
>  		sky2_tx_complete(sky2, last);
> +
> +		if (tx_avail(sky2) > MAX_SKB_TX_LE + 4)
> +			netif_wake_queue(dev);
> +	}
>  }
>  
>  static inline void sky2_skb_rx(const struct sky2_port *sky2,
> @@ -3197,6 +3198,7 @@ static int sky2_reattach(struct net_devi
>  		} else {
>  			netif_device_attach(dev);
>  			sky2_set_multicast(dev);
> +			netif_start_queue(dev);

Why netif_device_attach() is not enough?

Jarek P.