Am Freitag, 27. Februar 2009 schrieb Zhu Yi: > On Wed, 2009-02-25 at 20:39 +0800, Helmut Schaa wrote: > > Argh! Just found out why dev_activate is called such late after > > netif_carrier_on: > > > > ipw2100 calls netif_carrier_on followed by netif_wake_queue when the > > driver > > moves from associating to associated state. netif_carrier_on will then > > call linkwatch_fire_event. However the carrier_on event is not treated > > as > > urgent and as such the event is delayed (and thus dev_activate too). > > > > An event is considered urgent if the netdev is running, has a carrier > > _and_ any of the TX qdiscs changed. Since ipw2100 first calls > > carrier_on, > > the last condition is not met and thus the event is not considered > > urgent and gets delayed. > > Calling netif_wake_queue() before netif_carrier_on() is not correct in > semantics. Even it works, it looks like a workaround hack. I still think > making a sync version of netif_carrier_on is the way to go. Hmm, we could use register_netdevice_notifier to get notified when the carrier event is sent out and thus the tx queues are available. The flow in ipw2100 would then be: 1) isr_indicate_associated: - move to ASSOCIATING state - start buffering incoming frames 2) ipw2100_ex_event_work: - call carrier_on and wake_queues 3) netdevice_notification: - move to ASSOCIATED state and replay buffered frames I hope I'll find some time to try that soon. Helmut -- To unsubscribe from this list: send the line "unsubscribe linux-wireless" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
