iwlwifi: mvm: clean up iteration in iwl_mvm_inactivity_check()

There's no need to build a bitmap first and then iterate,
just do the iteration with the right locking directly.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: Luca Coelho <luciano.coelho@intel.com>

diff --git a/drivers/net/wireless/intel/iwlwifi/mvm/sta.c b/drivers/net/wireless/intel/iwlwifi/mvm/sta.c
index ce03f97..5b6ec7d 100644 (file)
--- a/drivers/net/wireless/intel/iwlwifi/mvm/sta.c
+++ b/drivers/net/wireless/intel/iwlwifi/mvm/sta.c
@@ -1353,7 +1353,6 @@ static void iwl_mvm_remove_inactive_tids(struct iwl_mvm *mvm,
 
 static void iwl_mvm_inactivity_check(struct iwl_mvm *mvm)
 {
-       unsigned long timeout_queues_map = 0;
        unsigned long now = jiffies;
        int i;
 
@@ -1361,22 +1360,18 @@ static void iwl_mvm_inactivity_check(struct iwl_mvm *mvm)
                return;
 
        spin_lock_bh(&mvm->queue_info_lock);
-       /* skip the CMD queue */
-       BUILD_BUG_ON(IWL_MVM_DQA_CMD_QUEUE != 0);
-       for (i = 1; i < IWL_MAX_HW_QUEUES; i++) {
-               if (mvm->queue_info[i].tid_bitmap)
-                       timeout_queues_map |= BIT(i);
-       }
-       spin_unlock_bh(&mvm->queue_info_lock);
 
        rcu_read_lock();
 
+       /* we skip the CMD queue below by starting at 1 */
+       BUILD_BUG_ON(IWL_MVM_DQA_CMD_QUEUE != 0);
+
        /*
         * If a queue times out - 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) {
+       for (i = 1; i < IWL_MAX_HW_QUEUES; i++) {
                struct ieee80211_sta *sta;
                struct iwl_mvm_sta *mvmsta;
                u8 sta_id;
@@ -1384,15 +1379,14 @@ static void iwl_mvm_inactivity_check(struct iwl_mvm *mvm)
                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 (!queue_tid_bitmap)
+                       continue;
 
                /* If TXQ isn't in active use anyway - nothing to do here... */
                if (mvm->queue_info[i].status != IWL_MVM_QUEUE_READY &&
-                   mvm->queue_info[i].status != IWL_MVM_QUEUE_SHARED) {
-                       spin_unlock_bh(&mvm->queue_info_lock);
+                   mvm->queue_info[i].status != IWL_MVM_QUEUE_SHARED)
                        continue;
-               }
 
                /* Check to see if there are inactive TIDs on this queue */
                for_each_set_bit(tid, &queue_tid_bitmap,
@@ -1403,7 +1397,6 @@ static void iwl_mvm_inactivity_check(struct iwl_mvm *mvm)
 
                        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)
@@ -1427,15 +1420,20 @@ static void iwl_mvm_inactivity_check(struct iwl_mvm *mvm)
 
                mvmsta = iwl_mvm_sta_from_mac80211(sta);
 
-               spin_lock_bh(&mvmsta->lock);
+               /* this isn't so nice, but works OK due to the way we loop */
+               spin_unlock(&mvm->queue_info_lock);
+
+               /* and we need this locking order */
+               spin_lock(&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);
+               /* only unlock sta lock - we still need the queue info lock */
+               spin_unlock(&mvmsta->lock);
        }
 
        rcu_read_unlock();
+       spin_unlock_bh(&mvm->queue_info_lock);
 }
 
 static inline u8 iwl_mvm_tid_to_ac_queue(int tid)