Tive Ethernet: Fix some race conditions in the driver that become apparent when debug is enabled

arch/arm/src/tiva/tm4c_ethernet.c

@@ -726,6 +726,10 @@ static void tiva_poll_expiry(int argc, uint32_t arg, ...);
 
 static int  tiva_ifup(struct net_driver_s *dev);
 static int  tiva_ifdown(struct net_driver_s *dev);
+static inline void tiva_txavail_process(FAR struct tiva_ethmac_s *priv);
+#ifdef CONFIG_NET_NOINTS
+static void tiva_txavail_work(FAR void *arg);
+#endif
 static int  tiva_txavail(struct net_driver_s *dev);
 #ifdef CONFIG_NET_IGMP
 static int  tiva_addmac(struct net_driver_s *dev, FAR const uint8_t *mac);
@@ -1820,7 +1824,7 @@ static void tiva_receive(FAR struct tiva_ethmac_s *priv)
 
 static void tiva_freeframe(FAR struct tiva_ethmac_s *priv)
 {
-  struct emac_txdesc_s *txdesc;
+  FAR struct emac_txdesc_s *txdesc;
   int i;
 
   nvdbg("txhead: %p txtail: %p inflight: %d\n",
@@ -1916,11 +1920,15 @@ static void tiva_freeframe(FAR struct tiva_ethmac_s *priv)
 
 static void tiva_txdone(FAR struct tiva_ethmac_s *priv)
 {
+  FAR struct net_driver_s *dev  = &priv->dev;
+
   DEBUGASSERT(priv->txtail != NULL);
 
   /* Scan the TX descriptor change, returning buffers to free list */
 
   tiva_freeframe(priv);
+  dev->d_buf = NULL;
+  dev->d_len = 0;
 
   /* If no further xmits are pending, then cancel the TX timeout */
 
@@ -2501,6 +2509,65 @@ static int tiva_ifdown(struct net_driver_s *dev)
   return OK;
 }
 
+/****************************************************************************
+ * Function: tiva_txavail_process
+ *
+ * Description:
+ *   Perform an out-of-cycle poll.
+ *
+ * Parameters:
+ *   priv - Reference to the NuttX driver state structure
+ *
+ * Returned Value:
+ *   None
+ *
+ * Assumptions:
+ *   Called in normal user mode
+ *
+ ****************************************************************************/
+
+static inline void tiva_txavail_process(FAR struct tiva_ethmac_s *priv)
+{
+  nvdbg("ifup: %d\n", priv->ifup);
+
+  /* Ignore the notification if the interface is not yet up */
+
+  if (priv->ifup)
+    {
+      /* Poll uIP for new XMIT data */
+
+      tiva_dopoll(priv);
+    }
+}
+
+/****************************************************************************
+ * Function: tiva_txavail_work
+ *
+ * Description:
+ *   Perform an out-of-cycle poll on the worker thread.
+ *
+ * Parameters:
+ *   arg  - Reference to the NuttX driver state structure (cast to void*)
+ *
+ * Returned Value:
+ *   None
+ *
+ * Assumptions:
+ *   Called on the higher priority worker thread.
+ *
+ ****************************************************************************/
+
+#ifdef CONFIG_NET_NOINTS
+static void tiva_txavail_work(FAR void *arg)
+{
+  FAR struct tiva_ethmac_s *priv = (FAR struct tiva_ethmac_s *)arg;
+
+  /* Perform the poll */
+
+  tiva_txavail_process(priv);
+}
+#endif
+
 /****************************************************************************
  * Function: tiva_txavail
  *
@@ -2523,9 +2590,22 @@ static int tiva_ifdown(struct net_driver_s *dev)
 static int tiva_txavail(struct net_driver_s *dev)
 {
   FAR struct tiva_ethmac_s *priv = (FAR struct tiva_ethmac_s *)dev->d_private;
-  irqstate_t flags;
 
-  nvdbg("ifup: %d\n", priv->ifup);
+#ifdef CONFIG_NET_NOINTS
+  /* Is our single work structure available?  It may not be if there are
+   * pending interrupt actions and we will have to ignore the Tx
+   * availability action.
+   */
+
+  if (work_available(&priv->work))
+    {
+      /* Schedule to serialize the poll on the worker thread. */
+
+      work_queue(HPWORK, &priv->work, tiva_txavail_work, priv, 0);
+    }
+
+#else
+  irqstate_t flags;
 
   /* Disable interrupts because this function may be called from interrupt
    * level processing.
@@ -2533,16 +2613,12 @@ static int tiva_txavail(struct net_driver_s *dev)
 
   flags = irqsave();
 
-  /* Ignore the notification if the interface is not yet up */
+  /* Perform the out-of-cycle poll now */
-
-  if (priv->ifup)
-    {
-      /* Poll uIP for new XMIT data */
-
-      tiva_dopoll(priv);
-    }
 
+  tiva_txavail_process(priv);
   irqrestore(flags);
+#endif
+
   return OK;
 }
 

drivers/net/skeleton.c

@@ -155,12 +155,16 @@ static void skel_poll_expiry(int argc, uint32_t arg, ...);
 
 /* NuttX callback functions */
 
-static int skel_ifup(struct net_driver_s *dev);
+static int skel_ifup(FAR struct net_driver_s *dev);
-static int skel_ifdown(struct net_driver_s *dev);
+static int skel_ifdown(FAR struct net_driver_s *dev);
-static int skel_txavail(struct net_driver_s *dev);
+static inline int skel_txavail_process(FAR struct skel_driver_s *skel);
+#ifdef CONFIG_NET_NOINTS
+static void skel_txavail_work(FAR void *arg);
+#endif
+static int skel_txavail(FAR struct net_driver_s *dev);
 #ifdef CONFIG_NET_IGMP
-static int skel_addmac(struct net_driver_s *dev, FAR const uint8_t *mac);
+static int skel_addmac(FAR struct net_driver_s *dev, FAR const uint8_t *mac);
-static int skel_rmmac(struct net_driver_s *dev, FAR const uint8_t *mac);
+static int skel_rmmac(FAR struct net_driver_s *dev, FAR const uint8_t *mac);
 #endif
 
 /****************************************************************************
@@ -826,6 +830,67 @@ static int skel_ifdown(struct net_driver_s *dev)
   return OK;
 }
 
+/****************************************************************************
+ * Function: skel_txavail_process
+ *
+ * Description:
+ *   Perform an out-of-cycle poll.
+ *
+ * Parameters:
+ *   dev  - Reference to the NuttX driver state structure
+ *
+ * Returned Value:
+ *   None
+ *
+ * Assumptions:
+ *   Called in normal user mode
+ *
+ ****************************************************************************/
+
+static int inline skel_txavail_process(FAR struct skel_driver_s *skel)
+{
+  /* Ignore the notification if the interface is not yet up */
+
+  if (skel->sk_bifup)
+    {
+      /* Check if there is room in the hardware to hold another outgoing packet. */
+
+      /* If so, then poll uIP for new XMIT data */
+
+      (void)devif_poll(&skel->sk_dev, skel_txpoll);
+    }
+
+  return OK;
+}
+
+/****************************************************************************
+ * Function: skel_txavail_work
+ *
+ * Description:
+ *   Perform an out-of-cycle poll on the worker thread.
+ *
+ * Parameters:
+ *   arg  - Reference to the NuttX driver state structure (cast to void*)
+ *
+ * Returned Value:
+ *   None
+ *
+ * Assumptions:
+ *   Called on the higher priority worker thread.
+ *
+ ****************************************************************************/
+
+#ifdef CONFIG_NET_NOINTS
+static void skel_txavail_work(FAR void *arg)
+{
+  FAR struct skel_driver_s *skel = (FAR struct skel_driver_s *)arg;
+
+  /* Perform the poll */
+
+  skel_txavail_process(skel);
+}
+#endif
+
 /****************************************************************************
  * Function: skel_txavail
  *
@@ -848,6 +913,21 @@ static int skel_ifdown(struct net_driver_s *dev)
 static int skel_txavail(struct net_driver_s *dev)
 {
   FAR struct skel_driver_s *skel = (FAR struct skel_driver_s *)dev->d_private;
+
+#ifdef CONFIG_NET_NOINTS
+  /* Is our single work structure available?  It may not be if there are
+   * pending interrupt actions and we will have to ignore the Tx
+   * availability action.
+   */
+
+  if (work_available(&skel->sk_work))
+    {
+      /* Schedule to serialize the poll on the worker thread. */
+
+      work_queue(HPWORK, &skel->sk_work, skel_txavail_work, skel, 0);
+    }
+
+#else
   irqstate_t flags;
 
   /* Disable interrupts because this function may be called from interrupt
@@ -856,18 +936,12 @@ static int skel_txavail(struct net_driver_s *dev)
 
   flags = irqsave();
 
-  /* Ignore the notification if the interface is not yet up */
+  /* Perform the out-of-cycle poll now */
-
-  if (skel->sk_bifup)
-    {
-      /* Check if there is room in the hardware to hold another outgoing packet. */
-
-      /* If so, then poll uIP for new XMIT data */
-
-      (void)devif_poll(&skel->sk_dev, skel_txpoll);
-    }
 
+  skel_poll_process(skel);
   irqrestore(flags);
+#endif
+
   return OK;
 }