[PATCH 2/2]: Spider ethernet driver -- protect chain head

[Linas Vepstas]

On Fri, Apr 21, 2006 at 05:11:40PM -0700, Eugene Surovegin wrote:
> On Fri, Apr 21, 2006 at 06:45:51PM -0500, Linas Vepstas wrote:
> > Prevent a potential race. If two threads are both calling
> > the transmit routine, both can potentially try to grab the
> > same dma descriptor. Serialize access to the head of the
> > tx ring with spinlocks.
> 
> Two threads cannot be in spider_net_xmit() simultaneosuly because 
> hard_start_xmit entry point is already protected by net_device 
> xmit_lock, see Documentation/net/netdevices.txt

Ahh, thank you. I was wondering why I never semmed to see this
this happen in "real life".

--linas