ieee802154: Improves notification freeing functionality

Each notification now has a number of clients.  When the last client calls free, the notification is freed back to the pool

wireless/ieee802154/mac802154.c

@@ -636,8 +636,8 @@ static void mac802154_purge_worker(FAR void *arg)
         /* Free the IOB, the notification, and the tx descriptor */
 
         iob_free(txdesc->frame);
-        ((FAR struct mac802154_notif_s *)txdesc->conf)->flink = priv->notif_free;
+        mac802154_notif_free_locked(priv,
-        priv->notif_free = ((FAR struct mac802154_notif_s *)txdesc->conf);
+          (FAR struct ieee802154_notif_s *)txdesc->conf);
         mac802154_txdesc_free(priv, txdesc);
         priv->beaconupdate = true;
 
@@ -760,7 +760,6 @@ static void mac802154_txdone_worker(FAR void *arg)
     (FAR struct ieee802154_privmac_s *)arg;
   FAR struct ieee802154_txdesc_s *txdesc;
   FAR struct ieee802154_notif_s *notif;
-  FAR struct mac802154_notif_s *privnotif;
 
   /* Get exclusive access to the driver structure.  We don't care about any
    * signals so don't allow interruptions
@@ -781,8 +780,7 @@ static void mac802154_txdone_worker(FAR void *arg)
        * notification structure to make it easier to use.
        */
 
-      privnotif = (FAR struct mac802154_notif_s *)txdesc->conf;
+      notif =(FAR struct ieee802154_notif_s *)txdesc->conf;
-      notif = &privnotif->pub;
 
       switch(txdesc->frametype)
         {
@@ -857,14 +855,7 @@ static void mac802154_txdone_worker(FAR void *arg)
                     break;
 
                   default:
-                    /* We can deallocate the data conf notification as it is no
+                    mac802154_notif_free_locked(priv, notif);
-                     * longer needed. We can't use the public function here
-                     * since we already have the MAC locked.
-                     */
-
-                    privnotif->flink = priv->notif_free;
-                    priv->notif_free = privnotif;
-                    priv->nnotif     = 0;
                     break;
                 }
             }
@@ -872,13 +863,7 @@ static void mac802154_txdone_worker(FAR void *arg)
 
           default:
             {
-              /* We can deallocate the data conf notification as it is no longer
+              mac802154_notif_free_locked(priv, notif);
-               * needed. We can't use the public function here since we already
-               * have the MAC locked.
-               */
-
-              privnotif->flink = priv->notif_free;
-              priv->notif_free = privnotif;
             }
             break;
         }

wireless/ieee802154/mac802154.h

@@ -368,7 +368,7 @@ int mac802154_resp_orphan(MACHANDLE mac,
  *
  ****************************************************************************/
 
-int mac802154_notif_free(MACHANDLE mac,
+void mac802154_notif_free(MACHANDLE mac,
                           FAR struct ieee802154_notif_s *notif);
 
 #undef EXTERN

wireless/ieee802154/mac802154_assoc.c

@@ -402,10 +402,9 @@ void mac802154_txdone_assocreq(FAR struct ieee802154_privmac_s *priv,
                                FAR struct ieee802154_txdesc_s *txdesc)
 {
   enum ieee802154_status_e status;
-  FAR struct mac802154_notif_s *privnotif =
-    (FAR struct mac802154_notif_s *)txdesc->conf;
-  FAR struct ieee802154_notif_s *notif = &privnotif->pub;
   FAR struct ieee802154_txdesc_s *respdesc;
+  FAR struct ieee802154_notif_s *notif =
+    (FAR struct ieee802154_notif_s *)txdesc->conf;
 
   if(txdesc->conf->status != IEEE802154_STATUS_SUCCESS)
     {
@@ -497,13 +496,9 @@ void mac802154_txdone_assocreq(FAR struct ieee802154_privmac_s *priv,
             (priv->resp_waittime*IEEE802154_BASE_SUPERFRAME_DURATION));
         }
 
-      /* We can deallocate the data conf notification as it is no longer
+      /* Deallocate the data conf notification as it is no longer needed. */
-       * needed. We can't use the public function here since we already
-       * have the MAC locked.
-       */
 
-      privnotif->flink = priv->notif_free;
+      mac802154_notif_free_locked(priv, notif);
-      priv->notif_free = privnotif;
     }
 }
 
@@ -524,9 +519,8 @@ void mac802154_txdone_datareq_assoc(FAR struct ieee802154_privmac_s *priv,
                                     FAR struct ieee802154_txdesc_s *txdesc)
 {
   enum ieee802154_status_e status;
-  FAR struct mac802154_notif_s *privnotif =
+  FAR struct ieee802154_notif_s *notif =
-    (FAR struct mac802154_notif_s *)txdesc->conf;
+    (FAR struct ieee802154_notif_s *)txdesc->conf;
-  FAR struct ieee802154_notif_s *notif = &privnotif->pub;
 
   /* If the data request failed to be sent, notify the next layer
    * that the association has failed.
@@ -595,14 +589,9 @@ void mac802154_txdone_datareq_assoc(FAR struct ieee802154_privmac_s *priv,
       mac802154_timerstart(priv, priv->max_frame_waittime,
                            mac802154_assoctimeout);
 
-      /* We can deallocate the data conf notification as it is no longer
+      /* Deallocate the data conf notification as it is no longer needed. */
-       * needed. We can't use the public function here since we already
-       * have the MAC locked.
-       */
 
-      privnotif->flink = priv->notif_free;
+      mac802154_notif_free_locked(priv, notif);
-      priv->notif_free = privnotif;
-      mac802154_givesem(&priv->notif_sem);
     }
 }
 

wireless/ieee802154/mac802154_notif.c

@@ -69,44 +69,22 @@
  *
  ****************************************************************************/
 
-int mac802154_notif_free(MACHANDLE mac,
+void mac802154_notif_free(MACHANDLE mac, FAR struct ieee802154_notif_s *notif)
-                         FAR struct ieee802154_notif_s *notif)
 {
   FAR struct ieee802154_privmac_s *priv =
     (FAR struct ieee802154_privmac_s *)mac;
-  FAR struct mac802154_notif_s *privnotif =
-    (FAR struct mac802154_notif_s *)notif;
 
-  /* Get exclusive access to the MAC */
+  /* Lock the MAC */
 
   mac802154_takesem(&priv->exclsem, false);
 
-  /* We know how many clients have registered for notifications.  Each must
+  /* Call the internal helper function to free the notification */
-   * call mac802154_notif_free() before we can release the notification
-   * resource.
-   */
 
-  if (priv->nnotif < 2)
+  mac802154_notif_free_locked(priv, notif);
-    {
-      /* This is the free from the last notification */
 
-      privnotif->flink = priv->notif_free;
+  /* Unlock the MAC */
-      priv->notif_free = privnotif;
-      priv->nnotif     = 0;
-
-      mac802154_givesem(&priv->notif_sem);
-    }
-  else
-    {
-      /* More calls are expected.  Decrement the count of expected calls
-       * and preserve the notification resources.
-       */
-
-      priv->nnotif--;
-    }
 
   mac802154_givesem(&priv->exclsem);
-  return -ENOTTY;
 }
 
 /****************************************************************************
@@ -184,9 +162,9 @@ int mac802154_notif_alloc(FAR struct ieee802154_privmac_s *priv,
 
   if (ret == OK)
     {
-      privnotif        = priv->notif_free;
+      privnotif         = priv->notif_free;
-      priv->notif_free = privnotif->flink;
+      priv->notif_free  = privnotif->flink;
-      priv->nnotif     = 0;
+      privnotif->nclients = 0;
     }
   else
     {
@@ -220,9 +198,9 @@ int mac802154_notif_alloc(FAR struct ieee802154_privmac_s *priv,
 
       /* We can now safely unlink the next free structure from the free list */
 
-      privnotif        = priv->notif_free;
+      privnotif           = priv->notif_free;
-      priv->notif_free = privnotif->flink;
+      priv->notif_free    = privnotif->flink;
-      priv->nnotif     = 0;
+      privnotif->nclients = 0;
     }
 
   *notif = (FAR struct ieee802154_notif_s *)privnotif;
@@ -230,6 +208,49 @@ int mac802154_notif_alloc(FAR struct ieee802154_privmac_s *priv,
   return OK;
 }
 
+/****************************************************************************
+ * Name: mac802154_notif_free_locked
+ *
+ * Description:
+ *   When the MAC calls the registered callback, it passes a reference
+ *   to a mac802154_notify_s structure.  This structure needs to be freed
+ *   after the callback handler is done using it.
+ *
+ *   Internal version that already has MAC locked
+ *
+ ****************************************************************************/
+
+void mac802154_notif_free_locked(FAR struct ieee802154_privmac_s * priv,
+                                 FAR struct ieee802154_notif_s *notif)
+{
+  FAR struct mac802154_notif_s *privnotif =
+    (FAR struct mac802154_notif_s *)notif;
+
+  /* We know how many clients have registered for notifications.  Each must
+   * call mac802154_notif_free() before we can release the notification
+   * resource.
+   */
+
+  if (privnotif->nclients < 2)
+    {
+      /* This is the free from the last notification */
+
+      privnotif->flink    = priv->notif_free;
+      priv->notif_free    = privnotif;
+      privnotif->nclients = 0;
+
+      mac802154_givesem(&priv->notif_sem);
+    }
+  else
+    {
+      /* More calls are expected.  Decrement the count of expected calls
+       * and preserve the notification resources.
+       */
+
+      privnotif->nclients--;
+    }
+}
+
 /****************************************************************************
  * Name: mac802154_notify
  *
@@ -242,12 +263,13 @@ void mac802154_notify(FAR struct ieee802154_privmac_s *priv,
                       FAR struct ieee802154_notif_s *notif)
 {
   FAR struct mac802154_maccb_s *cb;
+  FAR struct mac802154_notif_s *privnotif = (FAR struct mac802154_notif_s *)notif;
 
   /* Set the notification count so that the notification resources will be
    * preserved until the final notification.
    */
 
-  priv->nnotif = priv->nclients;
+  privnotif->nclients = priv->nclients;
 
   /* Try to notify every registered MAC client */
 

wireless/ieee802154/mac802154_notif.h

@@ -65,6 +65,7 @@ struct mac802154_notif_s
 {
   struct ieee802154_notif_s pub;        /* Publically visible structure */
   FAR struct mac802154_notif_s *flink;  /* Supports a singly linked list */
+  uint8_t nclients;
 };
 
 /****************************************************************************
@@ -82,4 +83,7 @@ int mac802154_notif_alloc(FAR struct ieee802154_privmac_s *priv,
 void mac802154_notify(FAR struct ieee802154_privmac_s *priv,
                       FAR struct ieee802154_notif_s *notif);
 
+void mac802154_notif_free_locked(FAR struct ieee802154_privmac_s * priv,
+                                 FAR struct ieee802154_notif_s *notif);
+
 #endif /* __WIRELESS_IEEE802154__MAC802154_NOTIF_H */

wireless/ieee802154/mac802154_poll.c

@@ -188,9 +188,8 @@ void mac802154_txdone_datareq_poll(FAR struct ieee802154_privmac_s *priv,
                                    FAR struct ieee802154_txdesc_s *txdesc)
 {
   enum ieee802154_status_e status;
-  FAR struct mac802154_notif_s *privnotif =
+  FAR struct ieee802154_notif_s *notif =
-    (FAR struct mac802154_notif_s *)txdesc->conf;
+    (FAR struct ieee802154_notif_s *)txdesc->conf;
-  FAR struct ieee802154_notif_s *notif = &privnotif->pub;
 
   /* If the data request failed to be sent, notify the next layer
    * that the poll has failed.
@@ -245,13 +244,9 @@ void mac802154_txdone_datareq_poll(FAR struct ieee802154_privmac_s *priv,
       mac802154_timerstart(priv, priv->max_frame_waittime,
                            mac802154_polltimeout);
 
-      /* We can deallocate the data conf notification as it is no longer
+      /* Deallocate the data conf notification as it is no longer needed. */
-       * needed. We can't use the public function here since we already
-       * have the MAC locked.
-       */
 
-      privnotif->flink = priv->notif_free;
+      mac802154_notif_free_locked(priv, notif);
-      priv->notif_free = privnotif;
     }
 }