Re: [PATCH 2/3] iwlwifi: mvm: start mac queues when deferred tx frames are purged

[Kalle Valo]

Luca Coelho  writes:

> From: Avraham Stern 
>
> Under DQA, when tx is deferred because a queue needs to be allocated,
> the mac queue for that TID is stopped until the new stream is added.
> If at this point the station that this stream belongs to is removed,
> all the deferred tx frames are purged, but the mac queue is not
> restarted. As a result, all following tx on this queue will not be
> transmitted.
>
> Fix this by starting the relevant mac queues when the deferred tx
> frames are purged.
>
> Fixes: 24afba7690e4 ("iwlwifi: mvm: support bss dynamic alloc/dealloc of 
> queues")
> Signed-off-by: Avraham Stern 
> Signed-off-by: Luca Coelho 

The commit log is not really explaining the bug from user's point of
view.

-- 
Kalle Valo

[PATCH 2/3] iwlwifi: mvm: start mac queues when deferred tx frames are purged

[Luca Coelho]

From: Avraham Stern 

Under DQA, when tx is deferred because a queue needs to be allocated,
the mac queue for that TID is stopped until the new stream is added.
If at this point the station that this stream belongs to is removed,
all the deferred tx frames are purged, but the mac queue is not
restarted. As a result, all following tx on this queue will not be
transmitted.

Fix this by starting the relevant mac queues when the deferred tx
frames are purged.

Fixes: 24afba7690e4 ("iwlwifi: mvm: support bss dynamic alloc/dealloc of 
queues")
Signed-off-by: Avraham Stern 
Signed-off-by: Luca Coelho 
---
 drivers/net/wireless/intel/iwlwifi/mvm/mac80211.c | 12 +++-
 1 file changed, 11 insertions(+), 1 deletion(-)

diff --git a/drivers/net/wireless/intel/iwlwifi/mvm/mac80211.c 
b/drivers/net/wireless/intel/iwlwifi/mvm/mac80211.c
index c7b1e58e3384..ce901be5fba8 100644
--- a/drivers/net/wireless/intel/iwlwifi/mvm/mac80211.c
+++ b/drivers/net/wireless/intel/iwlwifi/mvm/mac80211.c
@@ -2597,8 +2597,18 @@ static void iwl_mvm_purge_deferred_tx_frames(struct 
iwl_mvm *mvm,
spin_lock_bh(_sta->lock);
for (i = 0; i <= IWL_MAX_TID_COUNT; i++) {
tid_data = _sta->tid_data[i];
-   while ((skb = __skb_dequeue(_data->deferred_tx_frames)))
+
+   while ((skb = __skb_dequeue(_data->deferred_tx_frames))) {
+   struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
+
+   /*
+* The first deferred frame should've stopped the MAC
+* queues, so we should never get a second deferred
+* frame for the RA/TID.
+*/
+   iwl_mvm_start_mac_queues(mvm, info->hw_queue);
ieee80211_free_txskb(mvm->hw, skb);
+   }
}
spin_unlock_bh(_sta->lock);
 }
-- 
2.13.2