Re: Kernel WARNING: at net/core/dev.c:1330 __netif_schedule+0x2c/0x98()

Jarek Poplawski
2008-07-25T19:33:34Z

On Fri, Jul 25, 2008 at 09:16:24PM +0200, Johannes Berg wrote:
> On Fri, 2008-07-25 at 20:36 +0200, Jarek Poplawski wrote:
> > On Fri, Jul 25, 2008 at 07:04:36PM +0200, Ingo Oeser wrote:
> > ...
> > > I'm sure as hell, I miss sth. but can't it be done by this pseudo-code:
> >
> > ...And I really doubt it can't be done like this.
>
> Umm, of course it cannot, because then we'd have to take the mutex in
> the TX path, which we cannot. We cannot have another lock in the TX
> path, what's so hard to understand about? We need to be able to lock all
> queues to lock out multiple tx paths at once in some (really) slow paths
> but not have any extra lock overhead for the tx path, especially not a
> single lock.

But this mutex doesn't have to be mutex. And it's not for the tx path,
only for "service" just like netif_tx_lock(). The fast path needs only
queue->tx_lock.

Jarek P.