[tulip] race condition leading to hung tx queue in .92, .93

[Chris Friesen]

Donald Becker wrote:
> 
> On Fri, 15 Feb 2002, Chris Friesen wrote:

> > The fix is to change this code to the following:
> >
> >         if ( ! tp->tx_full)
> >                 netif_unpause_tx_queue(dev);
> >         else {
> >                 netif_stop_tx_queue(dev);
> >
> >                 /* handle case of tulip_interrupt() running under our feet */
> >                 if ( ! tp->tx_full)
> >                         netif_start_tx_queue(dev);
> >         }
> 
> Correct, although the preferred call is
>    netif_resume_tx_queue(dev)
> The
>    netif_start_tx_queue(dev);
> call currently does the same thing, but is intended to be used when the
> interface is first started.

The reason that I used netif_start_tx_queue() was that we're using
netif_stop_tx_queue() to stop it.  If we use netif_resume_tx_queue(), we'll be
left with dev->start set to zero.

I don't know if this is a problem, but it seems to me that we should use
matching sleep/wake routines, so either stop/start or pause/resume.


-- 
Chris Friesen                    | MailStop: 043/33/F10  
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