Re: [net-next PATCH 1/2] igbvf: add new driver to support 82576 virtual functions

[Andrew Morton <akpm@linux-foundation.org>]

On Wed, 18 Mar 2009 08:22:46 -0700 Alexander Duyck <alexander.h.duyck@intel.com> wrote:

> >>>> +static int igbvf_set_ringparam(struct net_device *netdev,
> >>>> +                               struct ethtool_ringparam *ring)
> >>>> +{
> >>>> +     struct igbvf_adapter *adapter = netdev_priv(netdev);
> >>>> +     struct igbvf_ring *tx_ring, *tx_old;
> >>>> +     struct igbvf_ring *rx_ring, *rx_old;
> >>>> +     int err;
> >>>> +
> >>>> +     if ((ring->rx_mini_pending) || (ring->rx_jumbo_pending))
> >>>> +             return -EINVAL;
> >>>> +
> >>>> +     while (test_and_set_bit(__IGBVF_RESETTING, &adapter->state))
> >>>> +             msleep(1);
> >>> No timeout needed here?  Interrupts might not be working, for example..
> >> This bit isn't set in interrupt context.  This is always used out of 
> >> interrupt context and is just to prevent multiple setting changes at the 
> >> same time.
> > 
> > Oh.  Can't use plain old mutex_lock()?
> 
> We have one or two spots that actually check to see if the bit is set 
> and just report a warning instead of actually waiting on the bit to clear.

mutex_is_locked()?