Re: [PATCH] netpoll: fix TX queue overflow in trapped mode

[Sergei Shtylyov <sshtylyov@ru.mvista.com>]

On Saturday 28 April 2007 22:12, you wrote:
> CONFIG_NETPOLL_TRAP causes the TX queue controls to be completely bypassed
> in the netpoll's "trapped" mode which easily causes overflows in the
> drivers with short TX queues (most notably, in 8139too with its 4-deep
> queue).  So, make this option more sensible by making it only bypass the TX
> softirq wakeup.

   Dammit!  Finally forgot to add acks earned so far:

> Signed-off-by: Sergei Shtylyov <sshtylyov@ru.mvista.com>
Acked-by: Jeff Garzik <jgarzik@pobox.com>
Acked-by: Matt Mackall <mpm@selenic.com>

> ---
> Split this part form the initial patch as request by Matt Mackall.
>
>  include/linux/netdevice.h |    8 +++-----
>  2 files changed, 3 insertions(+), 10 deletions(-)
>
> Index: linux-2.6/include/linux/netdevice.h
> ===================================================================
> --- linux-2.6.orig/include/linux/netdevice.h
> +++ linux-2.6/include/linux/netdevice.h
> @@ -647,8 +647,10 @@ static inline void netif_start_queue(str
>  static inline void netif_wake_queue(struct net_device *dev)
>  {
>  #ifdef CONFIG_NETPOLL_TRAP
> -	if (netpoll_trap())
> +	if (netpoll_trap()) {
> +		clear_bit(__LINK_STATE_XOFF, &dev->state);
>  		return;
> +	}
>  #endif
>  	if (test_and_clear_bit(__LINK_STATE_XOFF, &dev->state))
>  		__netif_schedule(dev);
> @@ -656,10 +658,6 @@ static inline void netif_wake_queue(stru
>
>  static inline void netif_stop_queue(struct net_device *dev)
>  {
> -#ifdef CONFIG_NETPOLL_TRAP
> -	if (netpoll_trap())
> -		return;
> -#endif
>  	set_bit(__LINK_STATE_XOFF, &dev->state);
>  }