On Wednesday 06/12 at 11:47 +0200, Felix Fietkau wrote: > On 2013-06-12 10:00 AM, Calvin Owens wrote: > > Copying the rate table should be done in an RCU read-side critical > > section. > I think this approach is wrong. The sta entry is also under RCU > protection (no locking for read access in that part of the code. > In a normal driver tx path, no extra rcu_read_lock/rcu_read_unlock is > needed. Only if the driver does some scheduling outside of the tx > function (which ath9k does), this RCU warning appears. > > How about this change instead: > --- > --- a/drivers/net/wireless/ath/ath9k/xmit.c > +++ b/drivers/net/wireless/ath/ath9k/xmit.c > @@ -1570,6 +1570,8 @@ void ath_txq_schedule(struct ath_softc * > txq->axq_ampdu_depth >= ATH_AGGR_MIN_QDEPTH) > return; > > + rcu_read_lock(); > + > ac = list_first_entry(&txq->axq_acq, struct ath_atx_ac, list); > last_ac = list_entry(txq->axq_acq.prev, struct ath_atx_ac, list); > > @@ -1608,8 +1610,10 @@ void ath_txq_schedule(struct ath_softc * > > if (ac == last_ac || > txq->axq_ampdu_depth >= ATH_AGGR_MIN_QDEPTH) > - return; > + break; > } > + > + rcu_read_unlock(); > } > > /***********/ > Yep, that stops the RCU warning for me. Tested-by: Calvin Owens <jcalvinowens@xxxxxxxxx> -- 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
