mac80211: add an intermediate software queue implementation

This allows drivers to request per-vif and per-sta-tid queues from which
they can pull frames. This makes it easier to keep the hardware queues
short, and to improve fairness between clients and vifs.

The task of scheduling packet transmission is left up to the driver -
queueing is controlled by mac80211. Drivers can only dequeue packets by
calling ieee80211_tx_dequeue. This makes it possible to add active queue
management later without changing drivers using this code.

This can also be used as a starting point to implement A-MSDU
aggregation in a way that does not add artificially induced latency.

Signed-off-by: Felix Fietkau <nbd@openwrt.org>
[resolved minor context conflict, minor changes, endian annotations]
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

1 files changed, 2 insertions, 0 deletions

diff --git a/net/mac80211/sta_info.h b/net/mac80211/sta_info.h
index 97f25b9..691d8a1 100644
--- a/net/mac80211/sta_info.h
+++ b/net/mac80211/sta_info.h
@@ -275,6 +275,7 @@ struct sta_ampdu_mlme {
  *	entered power saving state, these are also delivered to
  *	the station when it leaves powersave or polls for frames
  * @driver_buffered_tids: bitmap of TIDs the driver has data buffered on
+ * @txq_buffered_tids: bitmap of TIDs that mac80211 has txq data buffered on
  * @rx_packets: Number of MSDUs received from this STA
  * @rx_bytes: Number of bytes received from this STA
  * @last_rx: time (in jiffies) when last frame was received from this STA
@@ -369,6 +370,7 @@ struct sta_info {
 	struct sk_buff_head ps_tx_buf[IEEE80211_NUM_ACS];
 	struct sk_buff_head tx_filtered[IEEE80211_NUM_ACS];
 	unsigned long driver_buffered_tids;
+	unsigned long txq_buffered_tids;
 
 	/* Updated from RX path only, no locking requirements */
 	unsigned long rx_packets;