On Mon, Mar 23, 2009 at 01:37:49AM -0700, David Miller wrote: > From: Eric Dumazet <dada1@xxxxxxxxxxxxx> > Date: Mon, 23 Mar 2009 09:32:39 +0100 > > > I dont understand, doesnt it defeat the ticket spinlock thing and fairness ? > > > > Thread doing __qdisc_run() already owns the __QDISC_STATE_RUNNING bit. > > Right. > > Remember, the way this is designed is that if there is a busy > cpu taking packets out of the queue and putting them into the > device then other cpus will simply add to the queue and immediately > return. But this "busy cpu" can't take packets out of the queue when it's waiting on the contended spinlock. Anyway, it's only for testing, and I didn't say it has to be right. Jarek P. -- To unsubscribe from this list: send the line "unsubscribe linux-rt-users" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
