Commit 4db4e0a1 authored Nov 24, 2011 by Johannes Berg Committed by John W. Linville Nov 28, 2011

mac80211: fix TX warning



Emmanuel reported that my previous patches to enable
handing all fragments to drivers at once triggered
the warning that the SKB queue wasn't empty. This is
happening when we actually queue up some frames and
don't hand them to the driver (queues are stopped).

The reason for it is that my code that splices the
frame(s) over to the pending queue didn't re-init
the local queue, so skb_queue_empty() was false. Fix
this by using the _init versions of the splicing.

Also, convert the warning to WARN_ON_ONCE.

Reported-by: Emmanuel Grumbach <emmanuel.grumbach@intel.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Tested-by: Emmanuel Grumbach <emmanuel.grumbach@intel.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

parent 48839938

net/mac80211/tx.c

+4 −3

Original line number	Diff line number	Diff line
		@@ -1227,9 +1227,10 @@ static bool ieee80211_tx_frags(struct ieee80211_local *local,
		* queue is woken again.
		*/
		if (txpending)
		skb_queue_splice(skbs, &local->pending[q]);
		skb_queue_splice_init(skbs, &local->pending[q]);
		else
		skb_queue_splice_tail(skbs, &local->pending[q]);
		skb_queue_splice_tail_init(skbs,
		&local->pending[q]);

		spin_unlock_irqrestore(&local->queue_stop_reason_lock,
		flags);
		@@ -1301,7 +1302,7 @@ static bool __ieee80211_tx(struct ieee80211_local *local,
		ieee80211_tpt_led_trig_tx(local, fc, led_len);
		ieee80211_led_tx(local, 1);

		WARN_ON(!skb_queue_empty(skbs));
		WARN_ON_ONCE(!skb_queue_empty(skbs));

		return result;
		}

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