iwlwifi: mvm: support dqa queue inactivation upon timeout

Support marking queues as inactive upon a timeout expiring,
and allow inactive queues to be re-assigned to other RA/TIDs
if no other queue is free.

This is done by keeping a timestamp of the latest frame TXed
for every RA/TID, and then going over the queues currently in
use when a new queue is needed, inactivating all those that
are inactive.

Signed-off-by: Liad Kaufman <liad.kaufman@intel.com>
Signed-off-by: Luca Coelho <luciano.coelho@intel.com>

1 files changed, 165 insertions, 1 deletions

diff --git a/drivers/net/wireless/intel/iwlwifi/mvm/utils.c b/drivers/net/wireless/intel/iwlwifi/mvm/utils.c
index 161b99efd63d..a0cb5ca4c9b9 100644
--- a/drivers/net/wireless/intel/iwlwifi/mvm/utils.c
+++ b/drivers/net/wireless/intel/iwlwifi/mvm/utils.c
@@ -579,17 +579,29 @@ void iwl_mvm_dump_nic_error_log(struct iwl_mvm *mvm)
 		iwl_mvm_dump_umac_error_log(mvm);
 }
 
-int iwl_mvm_find_free_queue(struct iwl_mvm *mvm, u8 minq, u8 maxq)
+int iwl_mvm_find_free_queue(struct iwl_mvm *mvm, u8 sta_id, u8 minq, u8 maxq)
 {
 	int i;
 
 	lockdep_assert_held(&mvm->queue_info_lock);
 
+	/* Start by looking for a free queue */
 	for (i = minq; i <= maxq; i++)
 		if (mvm->queue_info[i].hw_queue_refcount == 0 &&
 		    mvm->queue_info[i].status == IWL_MVM_QUEUE_FREE)
 			return i;
 
+	/*
+	 * If no free queue found - settle for an inactive one to reconfigure
+	 * Make sure that the inactive queue either already belongs to this STA,
+	 * or that if it belongs to another one - it isn't the reserved queue
+	 */
+	for (i = minq; i <= maxq; i++)
+		if (mvm->queue_info[i].status == IWL_MVM_QUEUE_INACTIVE &&
+		    (sta_id == mvm->queue_info[i].ra_sta_id ||
+		     !mvm->queue_info[i].reserved))
+			return i;
+
 	return -ENOSPC;
 }
 
@@ -650,6 +662,7 @@ void iwl_mvm_enable_txq(struct iwl_mvm *mvm, int queue, int mac80211_queue,
 	else
 		mvm->queue_info[queue].ra_sta_id = cfg->sta_id;
 	mvm->queue_info[queue].tid_bitmap |= BIT(cfg->tid);
+	mvm->queue_info[queue].ra_sta_id = cfg->sta_id;
 
 	IWL_DEBUG_TX_QUEUES(mvm,
 			    "Enabling TXQ #%d refcount=%d (mac80211 map:0x%x)\n",
@@ -752,6 +765,9 @@ void iwl_mvm_disable_txq(struct iwl_mvm *mvm, int queue, int mac80211_queue,
 	mvm->queue_info[queue].tid_bitmap = 0;
 	mvm->queue_info[queue].hw_queue_to_mac80211 = 0;
 
+	/* Regardless if this is a reserved TXQ for a STA - mark it as false */
+	mvm->queue_info[queue].reserved = false;
+
 	spin_unlock_bh(&mvm->queue_info_lock);
 
 	iwl_trans_txq_disable(mvm->trans, queue, false);
@@ -1039,6 +1055,154 @@ out:
 	ieee80211_connection_loss(vif);
 }
 
+/*
+ * Remove inactive TIDs of a given queue.
+ * If all queue TIDs are inactive - mark the queue as inactive
+ * If only some the queue TIDs are inactive - unmap them from the queue
+ */
+static void iwl_mvm_remove_inactive_tids(struct iwl_mvm *mvm,
+					 struct iwl_mvm_sta *mvmsta, int queue,
+					 unsigned long tid_bitmap)
+{
+	int tid;
+
+	lockdep_assert_held(&mvmsta->lock);
+	lockdep_assert_held(&mvm->queue_info_lock);
+
+	/* Go over all non-active TIDs, incl. IWL_MAX_TID_COUNT (for mgmt) */
+	for_each_set_bit(tid, &tid_bitmap, IWL_MAX_TID_COUNT + 1) {
+		/* If some TFDs are still queued - don't mark TID as inactive */
+		if (iwl_mvm_tid_queued(&mvmsta->tid_data[tid]))
+			tid_bitmap &= ~BIT(tid);
+	}
+
+	/* If all TIDs in the queue are inactive - mark queue as inactive. */
+	if (tid_bitmap == mvm->queue_info[queue].tid_bitmap) {
+		mvm->queue_info[queue].status = IWL_MVM_QUEUE_INACTIVE;
+
+		for_each_set_bit(tid, &tid_bitmap, IWL_MAX_TID_COUNT + 1)
+			mvmsta->tid_data[tid].is_tid_active = false;
+
+		IWL_DEBUG_TX_QUEUES(mvm, "Queue %d marked as inactive\n",
+				    queue);
+		return;
+	}
+
+	/*
+	 * If we are here, this is a shared queue and not all TIDs timed-out.
+	 * Remove the ones that did.
+	 */
+	for_each_set_bit(tid, &tid_bitmap, IWL_MAX_TID_COUNT + 1) {
+		int mac_queue = mvmsta->vif->hw_queue[tid_to_mac80211_ac[tid]];
+
+		mvmsta->tid_data[tid].txq_id = IEEE80211_INVAL_HW_QUEUE;
+		mvm->queue_info[queue].hw_queue_to_mac80211 &= ~BIT(mac_queue);
+		mvm->queue_info[queue].hw_queue_refcount--;
+		mvm->queue_info[queue].tid_bitmap &= ~BIT(tid);
+		mvmsta->tid_data[tid].is_tid_active = false;
+
+		IWL_DEBUG_TX_QUEUES(mvm,
+				    "Removing inactive TID %d from shared Q:%d\n",
+				    tid, queue);
+	}
+
+	IWL_DEBUG_TX_QUEUES(mvm,
+			    "TXQ #%d left with tid bitmap 0x%x\n", queue,
+			    mvm->queue_info[queue].tid_bitmap);
+
+	/*
+	 * There may be different TIDs with the same mac queues, so make
+	 * sure all TIDs have existing corresponding mac queues enabled
+	 */
+	tid_bitmap = mvm->queue_info[queue].tid_bitmap;
+	for_each_set_bit(tid, &tid_bitmap, IWL_MAX_TID_COUNT + 1) {
+		mvm->queue_info[queue].hw_queue_to_mac80211 |=
+			BIT(mvmsta->vif->hw_queue[tid_to_mac80211_ac[tid]]);
+	}
+
+	/* TODO: if queue was shared - need to re-enable AGGs */
+}
+
+void iwl_mvm_inactivity_check(struct iwl_mvm *mvm)
+{
+	unsigned long timeout_queues_map = 0;
+	unsigned long now = jiffies;
+	int i;
+
+	spin_lock_bh(&mvm->queue_info_lock);
+	for (i = 0; i < IWL_MAX_HW_QUEUES; i++)
+		if (mvm->queue_info[i].hw_queue_refcount > 0)
+			timeout_queues_map |= BIT(i);
+	spin_unlock_bh(&mvm->queue_info_lock);
+
+	rcu_read_lock();
+
+	/*
+	 * If a queue time outs - mark it as INACTIVE (don't remove right away
+	 * if we don't have to.) This is an optimization in case traffic comes
+	 * later, and we don't HAVE to use a currently-inactive queue
+	 */
+	for_each_set_bit(i, &timeout_queues_map, IWL_MAX_HW_QUEUES) {
+		struct ieee80211_sta *sta;
+		struct iwl_mvm_sta *mvmsta;
+		u8 sta_id;
+		int tid;
+		unsigned long inactive_tid_bitmap = 0;
+		unsigned long queue_tid_bitmap;
+
+		spin_lock_bh(&mvm->queue_info_lock);
+		queue_tid_bitmap = mvm->queue_info[i].tid_bitmap;
+
+		/* If TXQ isn't in active use anyway - nothing to do here... */
+		if (mvm->queue_info[i].status != IWL_MVM_QUEUE_READY) {
+			spin_unlock_bh(&mvm->queue_info_lock);
+			continue;
+		}
+
+		/* Check to see if there are inactive TIDs on this queue */
+		for_each_set_bit(tid, &queue_tid_bitmap,
+				 IWL_MAX_TID_COUNT + 1) {
+			if (time_after(mvm->queue_info[i].last_frame_time[tid] +
+				       IWL_MVM_DQA_QUEUE_TIMEOUT, now))
+				continue;
+
+			inactive_tid_bitmap |= BIT(tid);
+		}
+		spin_unlock_bh(&mvm->queue_info_lock);
+
+		/* If all TIDs are active - finish check on this queue */
+		if (!inactive_tid_bitmap)
+			continue;
+
+		/*
+		 * If we are here - the queue hadn't been served recently and is
+		 * in use
+		 */
+
+		sta_id = mvm->queue_info[i].ra_sta_id;
+		sta = rcu_dereference(mvm->fw_id_to_mac_id[sta_id]);
+
+		/*
+		 * If the STA doesn't exist anymore, it isn't an error. It could
+		 * be that it was removed since getting the queues, and in this
+		 * case it should've inactivated its queues anyway.
+		 */
+		if (IS_ERR_OR_NULL(sta))
+			continue;
+
+		mvmsta = iwl_mvm_sta_from_mac80211(sta);
+
+		spin_lock_bh(&mvmsta->lock);
+		spin_lock(&mvm->queue_info_lock);
+		iwl_mvm_remove_inactive_tids(mvm, mvmsta, i,
+					     inactive_tid_bitmap);
+		spin_unlock(&mvm->queue_info_lock);
+		spin_unlock_bh(&mvmsta->lock);
+	}
+
+	rcu_read_unlock();
+}
+
 int iwl_mvm_send_lqm_cmd(struct ieee80211_vif *vif,
 			 enum iwl_lqm_cmd_operatrions operation,
 			 u32 duration, u32 timeout)