[openib-general] Re: [PATCH]: was Re: LLTX and netif_stop_queue

[Andi Kleen]

On Wed, Jan 26, 2005 at 11:22:27PM -0800, David S. Miller wrote:
> On Thu, 27 Jan 2005 08:16:45 +0100
> Andi Kleen <ak at suse.de> wrote:
> 
> > > Yes, that's the idea.
> > 
> > per CPU only works in preemptive kernel if you have preemption
> > disabled all the time. Do you? 
> > 
> > Seems not likely to me.
> 
> BH is disabled in these code paths (specifically we're talking
> about ->hard_start_xmit()), as that is where the recursion
> check goes.

Hmm, but hard_start_xmit is allowed to enable preemption again, isn't it?

An safer alternative may be to change the cpu mask of the current process
temporarily.

-Andi