From: Johannes Berg <johannes.berg@xxxxxxxxx> mac80211 will expire normal PS-buffered frames, but if the device rejected some frames for a sleeping station, these won't be on the ps_tx_buf queue but on the tx_filtered queue instead; this is done to avoid reordering. However, mac80211 will not expire frames from the filtered queue, let's fix that. Also add a more comments to what all this expiry is doing and how it works. Signed-off-by: Johannes Berg <johannes.berg@xxxxxxxxx> --- net/mac80211/sta_info.c | 57 +++++++++++++++++++++++++++++++++++++++++++----- net/mac80211/status.c | 5 ++++ 2 files changed, 57 insertions(+), 5 deletions(-) --- a/net/mac80211/sta_info.c 2011-09-07 14:32:37.000000000 +0200 +++ b/net/mac80211/sta_info.c 2011-09-07 14:32:38.000000000 +0200 @@ -698,6 +698,39 @@ static bool sta_info_cleanup_expire_buff unsigned long flags; struct sk_buff *skb; + /* + * First check for frames that should expire on the filtered + * queue. Frames here were rejected by the driver and are on + * a separate queue to avoid reordering with normal PS-buffered + * frames. They also aren't accounted for right now in the + * total_ps_buffered counter. + */ + for (;;) { + spin_lock_irqsave(&sta->tx_filtered.lock, flags); + skb = skb_peek(&sta->tx_filtered); + if (sta_info_buffer_expired(sta, skb)) + skb = __skb_dequeue(&sta->tx_filtered); + else + skb = NULL; + spin_unlock_irqrestore(&sta->tx_filtered.lock, flags); + + /* + * Frames are queued in order, so if this one + * hasn't expired yet we can stop testing. If + * we actually reached the end of the queue we + * also need to stop, of course. + */ + if (!skb) + break; + dev_kfree_skb(skb); + } + + /* + * Now also check the normal PS-buffered queue, this will + * only find something if the filtered queue was emptied + * since the filtered frames are all before the normal PS + * buffered frames. + */ for (;;) { spin_lock_irqsave(&sta->ps_tx_buf.lock, flags); skb = skb_peek(&sta->ps_tx_buf); @@ -707,6 +740,11 @@ static bool sta_info_cleanup_expire_buff skb = NULL; spin_unlock_irqrestore(&sta->ps_tx_buf.lock, flags); + /* + * frames are queued in order, so if this one + * hasn't expired yet (or we reached the end of + * the queue) we can stop testing + */ if (!skb) break; @@ -716,13 +754,22 @@ static bool sta_info_cleanup_expire_buff sta->sta.addr); #endif dev_kfree_skb(skb); - - /* if the queue is now empty recalc TIM bit */ - if (skb_queue_empty(&sta->ps_tx_buf)) - sta_info_recalc_tim(sta); } - return !skb_queue_empty(&sta->ps_tx_buf); + /* + * Finally, recalculate the TIM bit for this station -- it might + * now be clear because the station was too slow to retrieve its + * frames. + */ + sta_info_recalc_tim(sta); + + /* + * Return whether there are any frames still buffered, this is + * used to check whether the cleanup timer still needs to run, + * if there are no frames we don't need to rearm the timer. + */ + return !(skb_queue_empty(&sta->ps_tx_buf) && + skb_queue_empty(&sta->tx_filtered)); } static int __must_check __sta_info_destroy(struct sta_info *sta) --- a/net/mac80211/status.c 2011-09-07 14:32:37.000000000 +0200 +++ b/net/mac80211/status.c 2011-09-07 14:32:38.000000000 +0200 @@ -107,6 +107,11 @@ static void ieee80211_handle_filtered_fr skb_queue_len(&sta->tx_filtered) < STA_MAX_TX_BUFFER) { skb_queue_tail(&sta->tx_filtered, skb); sta_info_recalc_tim(sta); + + if (!timer_pending(&local->sta_cleanup)) + mod_timer(&local->sta_cleanup, + round_jiffies(jiffies + + STA_INFO_CLEANUP_INTERVAL)); return; } -- 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