Remove recursion from MAC layer ARMmbed#2 (ARMmbed#1830)

Use event to report data request failure to avoid recursion. In case
of event sending fails then call error handler directly.

Author: Arto Kinnunen

source/MAC/IEEE802_15_4/mac_defines.h

@@ -136,6 +136,11 @@ typedef struct mac_tx_status_t {
     uint8_t retry;
 } mac_tx_status_t;
 
+typedef struct mac_mcps_data_conf_fail_s {
+    uint8_t msduHandle;     /**< Handle associated with MSDU */
+    uint8_t status;         /**< Status of the failing MSDU transmission */
+} mac_mcps_data_conf_fail_t;
+
 typedef struct protocol_interface_rf_mac_setup {
     int8_t mac_interface_id;
     bool macUpState;
@@ -231,6 +236,7 @@ typedef struct protocol_interface_rf_mac_setup {
     uint8_t max_ED;
     uint16_t mlme_ED_counter;
     mac_tx_status_t mac_tx_status;
+    mac_mcps_data_conf_fail_t mac_mcps_data_conf_fail;
     struct cca_structure_s *cca_structure;
     /* MAC Security components */
     struct mlme_device_descriptor_s *device_description_table;

source/MAC/IEEE802_15_4/mac_mcps_sap.c

@@ -70,6 +70,7 @@ static void mac_set_active_event(protocol_interface_rf_mac_setup_s *rf_mac_setup
 static void mac_clear_active_event(protocol_interface_rf_mac_setup_s *rf_mac_setup, uint8_t event_type);
 static bool mac_read_active_event(protocol_interface_rf_mac_setup_s *rf_mac_setup, uint8_t event_type);
 static int8_t mcps_pd_data_cca_trig(protocol_interface_rf_mac_setup_s *rf_ptr, mac_pre_build_frame_t *buffer);
+static void mac_pd_data_confirm_failure_handle(protocol_interface_rf_mac_setup_s *rf_mac_setup);
 
 static int8_t mac_tasklet_event_handler = -1;
 
@@ -362,13 +363,14 @@ void mcps_sap_data_req_handler_ext(protocol_interface_rf_mac_setup_s *rf_mac_set
 
     verify_status:
     if (status != MLME_SUCCESS){
-        mcps_data_conf_t confirm;
-        memset(&confirm, 0, sizeof(mcps_data_conf_t));
-        confirm.msduHandle = data_req->msduHandle;
-        confirm.status = status;
         tr_debug("DATA REQ Fail %u", status);
+        rf_mac_setup->mac_mcps_data_conf_fail.msduHandle = data_req->msduHandle;
+        rf_mac_setup->mac_mcps_data_conf_fail.status = status;
         mcps_sap_prebuild_frame_buffer_free(buffer);
-        mcps_data_confirm_cb(rf_mac_setup, &confirm, NULL);
+        if (mcps_sap_pd_confirm_failure(rf_mac_setup) != 0) {
+            // event sending failed, calling handler directly
+            mac_pd_data_confirm_failure_handle(rf_mac_setup);
+        }
     }
 }
 
@@ -1093,7 +1095,6 @@ void mac_mcps_trig_buffer_from_queue(protocol_interface_rf_mac_setup_s *rf_mac_s
     }
 }
 
-
 static int8_t mac_ack_sap_rx_handler(mac_pre_parsed_frame_t *buf, protocol_interface_rf_mac_setup_s *rf_mac_setup)
 {
     //allocate Data ind primitiv and parse packet to that
@@ -1144,6 +1145,14 @@ static void mac_pd_data_confirm_handle(protocol_interface_rf_mac_setup_s *rf_mac
     mac_mcps_trig_buffer_from_queue(rf_mac_setup);
 }
 
+static void mac_pd_data_confirm_failure_handle(protocol_interface_rf_mac_setup_s *rf_mac_setup)
+{
+    mcps_data_conf_t mcps_data_conf;
+    memset(&mcps_data_conf, 0, sizeof(mcps_data_conf_t));
+    mcps_data_conf.msduHandle = rf_mac_setup->mac_mcps_data_conf_fail.msduHandle;
+    mcps_data_conf.status = rf_mac_setup->mac_mcps_data_conf_fail.status;
+    mcps_data_confirm_cb(rf_mac_setup, &mcps_data_conf, NULL);
+}
 
 static void mac_pd_data_ack_handler(mac_pre_parsed_frame_t *buf)
 {
@@ -1187,6 +1196,10 @@ static void mac_mcps_sap_data_tasklet(arm_event_s *event)
             mac_pd_data_confirm_handle((protocol_interface_rf_mac_setup_s*)event->data_ptr);
             break;
 
+        case MCPS_SAP_DATA_CNF_FAIL_EVENT:
+            mac_pd_data_confirm_failure_handle((protocol_interface_rf_mac_setup_s*)event->data_ptr);
+            break;
+
         case MCPS_SAP_DATA_ACK_CNF_EVENT:
             mac_pd_data_ack_handler((mac_pre_parsed_frame_t*)event->data_ptr);
             break;
@@ -1907,7 +1920,14 @@ void mcps_sap_pd_req_queue_write(protocol_interface_rf_mac_setup_s *rf_mac_setup
         if (mcps_pd_data_request(rf_mac_setup, buffer) != 0) {
             rf_mac_setup->mac_tx_result = MAC_TX_PRECOND_FAIL;
             rf_mac_setup->macTxRequestAck = false;
-            mcps_sap_pd_confirm(rf_mac_setup);
+            if (mcps_sap_pd_confirm(rf_mac_setup) != 0) {
+                // can't send event, try calling error handler directly
+                rf_mac_setup->mac_mcps_data_conf_fail.msduHandle = buffer->msduHandle;
+                rf_mac_setup->mac_mcps_data_conf_fail.status = buffer->status;
+                mcps_sap_prebuild_frame_buffer_free(buffer);
+                rf_mac_setup->active_pd_data_request = NULL;
+                mac_pd_data_confirm_failure_handle(rf_mac_setup);
+            }
         }
 
         return;
@@ -2087,10 +2107,10 @@ int8_t mcps_sap_pd_ind(mac_pre_parsed_frame_t *buffer)
     return eventOS_event_send(&event);
 }
 
-void mcps_sap_pd_confirm(void *mac_ptr)
+int8_t mcps_sap_pd_confirm(void *mac_ptr)
 {
     if (mac_tasklet_event_handler < 0  || !mac_ptr) {
-        return;
+        return -2;
     }
     arm_event_s event = {
         .receiver = mac_tasklet_event_handler,
@@ -2101,8 +2121,24 @@ void mcps_sap_pd_confirm(void *mac_ptr)
         .priority = ARM_LIB_HIGH_PRIORITY_EVENT,
     };
 
-    eventOS_event_send(&event);
+    return eventOS_event_send(&event);
+}
 
+int8_t mcps_sap_pd_confirm_failure(void *mac_ptr)
+{
+    if (mac_tasklet_event_handler < 0  || !mac_ptr) {
+        return -2;
+    }
+    arm_event_s event = {
+        .receiver = mac_tasklet_event_handler,
+        .sender = 0,
+        .event_id = 0,
+        .data_ptr = mac_ptr,
+        .event_type = MCPS_SAP_DATA_CNF_FAIL_EVENT,
+        .priority = ARM_LIB_HIGH_PRIORITY_EVENT,
+    };
+
+    return eventOS_event_send(&event);
 }
 
 void mcps_sap_pd_ack(void *ack_ptr)

source/MAC/IEEE802_15_4/mac_mcps_sap.h

@@ -48,14 +48,14 @@ typedef enum {
 #define MAC_PD_DATA_MEDIUM_PRIORITY 1    //Indirect Data which is polled
 #define MAC_PD_DATA_HIGH_PRIOTITY   2    //Beacon request Beacon response
 
-#define MCPS_SAP_DATA_IND_EVENT 1
-#define MCPS_SAP_DATA_CNF_EVENT 2
-#define MAC_MLME_EVENT_HANDLER  3
-#define MAC_MCPS_INDIRECT_TIMER_CB 4
-#define MAC_MLME_SCAN_CONFIRM_HANDLER 5
-#define MAC_SAP_TRIG_TX 6
-#define MCPS_SAP_DATA_ACK_CNF_EVENT 7
-
+#define MCPS_SAP_DATA_IND_EVENT         1
+#define MCPS_SAP_DATA_CNF_EVENT         2
+#define MCPS_SAP_DATA_CNF_FAIL_EVENT    3
+#define MAC_MLME_EVENT_HANDLER          4
+#define MAC_MCPS_INDIRECT_TIMER_CB      5
+#define MAC_MLME_SCAN_CONFIRM_HANDLER   6
+#define MAC_SAP_TRIG_TX                 7
+#define MCPS_SAP_DATA_ACK_CNF_EVENT     8
 
 /**
  * @brief struct mac_aux_security_header_t MAC auxiliarity security header structure
@@ -180,7 +180,9 @@ int8_t mcps_sap_pd_ind(mac_pre_parsed_frame_t *buffer);
 /**
  * MAC MCPS SAP layer data confirmation event trig
  */
-void mcps_sap_pd_confirm(void *mac_ptr);
+int8_t mcps_sap_pd_confirm(void *mac_ptr);
+
+int8_t mcps_sap_pd_confirm_failure(void *mac_ptr);
 
 void mcps_sap_pd_ack(void *ack_ptr);
 

test/nanostack/unittest/mac/mac_mcps_sap/test_mac_mcps_sap.c

@@ -2463,8 +2463,7 @@ bool test_mcps_sap_data_req_handler()
     nsdynmemlib_stub.returnCounter = 1;
     data_req.msduHandle = msdu_handle++;
     mcps_sap_data_req_handler(rf_mac_setup, &data_req);
-    /* async callback is not called, active_pd_data_request available in rf_mac_setup */
-    if (!rf_mac_setup->active_pd_data_request || data_confirm_valid) {
+    if (rf_mac_setup->active_pd_data_request || !data_confirm_valid) {
         return false;
     }
 
@@ -2477,8 +2476,7 @@ bool test_mcps_sap_data_req_handler()
     data_req.TxAckReq = true;
     mcps_sap_data_req_handler(rf_mac_setup, &data_req);
     data_req.msduHandle = msdu_handle++;
-    /* async callback is not called, active_pd_data_request available in rf_mac_setup */
-    if (!rf_mac_setup->active_pd_data_request || data_confirm_valid) {
+    if (rf_mac_setup->active_pd_data_request || !data_confirm_valid) {
         return false;
     }
 

test/nanostack/unittest/stub/mac_mcps_sap_stub.c

@@ -115,8 +115,14 @@ int8_t mcps_sap_pd_ind(mac_pre_parsed_frame_t *buffer)
     return mac_mcps_sap_stub.int8_value;
 }
 
-void mcps_sap_pd_confirm(void *mac_ptr)
+int8_t mcps_sap_pd_confirm(void *mac_ptr)
 {
+    return 0;
+}
+
+int8_t mcps_sap_pd_confirm_failure(void *mac_ptr)
+{
+    return 0;
 }
 
 void mcps_sap_pd_ack(void *ack_ptr)