On Mon, Feb 25, 2008 at 11:51 AM, Johannes Berg <johannes@xxxxxxxxxxxxxxxx> wrote: > > > > With iwlwifi, however, there is a possibility that it invokes > > > ieee80211_tx_status() on one CPU while mac80211's tasklet is processing > > > another TX status that was submitted with ieee80211_tx_status_irqsafe(). > > > Tomas, I think you mentioned that the TX status processing can't > > > actually ever call the non-irqsafe version, can we remove that call to > > > be sure? :) > > > > Actually alike athk also iwlwifi driver calls tx_status from a tasklet > > therfore the irqsafe can be removed. I've tested that it worked so far > > Ok, fine too. Just the mixing is actually bad because of locking. There'll be a patch for it. > > > However we added start_tx_ba_cb(_irqsafe) callback to get around AMPDU > > queues reordering > > In this case we have to use both handlers so I wonder where we have > > problem here as the same mechanism as tx_status is used. > > I think the AMPDU stuff has its own spinlock around the fields it > accesses in those things. The thing with the tx status etc. is that it > uses no locking to update a few sta_info fields. If we added locking > around those accesses, mixing the two irqsafe/non-irqsafe versions would > be acceptable, but I don't see much point in that. Great. > > > In general I'm missing some asynchronous mechanism that driver can > > notify mac80211 about it's state. > > Except BA states there is for example netif_carrier_off/on > > functionality in the driver level. It would be very useful for early > > notification of disconnection. A disconnection can happen due to > > device resume or internal recoverable error. In this cases I would > > expect mac to try associate again upon such trigger. > > I guess that's just missing. You can stop the queues but you can't tell > mac80211 that you reset the hw. If there is no objection we will introduce some notification mechanism...suggestions are welcome as well. Thanks Tomas > johannes > - 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
