Do not send too old packets (ARMmbed#2632)

* Do not send packets that are queued on adaptation layer over 30 seconds

* Do not allow new data request overtake existing one in MAC queue

* Revert "Do not allow new data request overtake existing one in MAC queue"

This reverts commit 5c660e0246139acd1dab99094fe3fdcf1138ad60.

* Do not send any old packets

* Return data request to adaptation layer after timeout

* Fixed missing PHY timestamp cb in unit tests

* Allow removing only normal priority buffers

* Unit tests for removing old buffers from MAC queue

* Cleaning

* Timeout value defined for all buffer priorities

* Updated unit tests

* Updated change log

CHANGELOG.md

@@ -6,6 +6,7 @@
 * Filter RPL parents based on DEVICE_MIN_SENS configuration with Threshold and Hysteresis.
 * Filter EAPOL parents based on DEVICE_MIN_SENS configuration with Threshold and Hysteresis to prevent EAPOL failures caused by bad signal levels
 * Adaptation layer removes oldest packets first when stack needs to release memory or reduce traffic
+* Use QoS specific timeout to drop old packets from TX queue to prioritize limited bandwidth.
 
 ### Changes
 * Statistics for MAC data request latencies. Separated to adaptation layer and MAC queueing delays.

source/6LoWPAN/adaptation_interface.c

@@ -120,6 +120,10 @@ typedef struct {
 #define LOWPAN_MEM_LIMIT_REMOVE_MAX 10000 // Remove when at memory limit
 #define LOWPAN_MEM_LIMIT_REMOVE_EF_MODE 20000 // Remove when out of memory and we are in EF mode
 
+#define LOWPAN_TX_BUFFER_AGE_LIMIT_LOW_PRIORITY     30 // Remove low priority packets older than limit (seconds)
+#define LOWPAN_TX_BUFFER_AGE_LIMIT_HIGH_PRIORITY    60 // Remove high priority packets older than limit (seconds)
+#define LOWPAN_TX_BUFFER_AGE_LIMIT_EF_PRIORITY      120 // Remove expedited forwarding packets older than limit (seconds)
+
 
 
 static NS_LIST_DEFINE(fragmenter_interface_list, fragmenter_interface_t, link);
@@ -1294,6 +1298,23 @@ void lowpan_adaptation_interface_slow_timer(protocol_interface_info_entry_t *cur
     }
 }
 
+static bool lowpan_adaptation_interface_check_buffer_timeout(buffer_t *buf)
+{
+    // Convert from 100ms slots to seconds
+    uint32_t buffer_age_s = (protocol_core_monotonic_time - buf->adaptation_timestamp) / 10;
+
+    if ((buf->priority == QOS_NORMAL) && (buffer_age_s > LOWPAN_TX_BUFFER_AGE_LIMIT_LOW_PRIORITY)) {
+        return true;
+    } else if ((buf->priority == QOS_HIGH) && (buffer_age_s > LOWPAN_TX_BUFFER_AGE_LIMIT_HIGH_PRIORITY)) {
+        return true;
+    } else if ((buf->priority == QOS_NETWORK_CTRL) && (buffer_age_s > LOWPAN_TX_BUFFER_AGE_LIMIT_HIGH_PRIORITY)) {
+        return true;
+    } else if ((buf->priority == QOS_EXPEDITE_FORWARD) && (buffer_age_s > LOWPAN_TX_BUFFER_AGE_LIMIT_EF_PRIORITY)) {
+        return true;
+    }
+    return false;
+}
+
 int8_t lowpan_adaptation_interface_tx(protocol_interface_info_entry_t *cur, buffer_t *buf)
 {
     bool is_room_for_new_message;
@@ -1309,13 +1330,7 @@ int8_t lowpan_adaptation_interface_tx(protocol_interface_info_entry_t *cur, buff
     if (!interface_ptr) {
         goto tx_error_handler;
     }
-    // Set TX start timestamp
-    if (!buf->adaptation_timestamp) {
-        buf->adaptation_timestamp = protocol_core_monotonic_time;
-        if (!buf->adaptation_timestamp) {
-            buf->adaptation_timestamp--;
-        }
-    }
+
     uint8_t traffic_class = buf->options.traffic_class >> IP_TCLASS_DSCP_SHIFT;
 
     if (traffic_class == IP_DSCP_EF) {
@@ -1327,6 +1342,18 @@ int8_t lowpan_adaptation_interface_tx(protocol_interface_info_entry_t *cur, buff
         buffer_priority_set(buf, QOS_HIGH);
     }
 
+    if (!buf->adaptation_timestamp) {
+        // Set TX start timestamp
+        buf->adaptation_timestamp = protocol_core_monotonic_time;
+        if (!buf->adaptation_timestamp) {
+            buf->adaptation_timestamp--;
+        }
+    } else if (lowpan_adaptation_interface_check_buffer_timeout(buf)) {
+        // Remove old buffers
+        socket_tx_buffer_event_and_free(buf, SOCKET_TX_FAIL);
+        return -1;
+    }
+
     //Update priority status
     lowpan_adaptation_priority_status_update(cur, interface_ptr, buf->priority);
 

source/MAC/IEEE802_15_4/mac_mcps_sap.c

@@ -56,6 +56,9 @@
 
 // Used to set TX time (us) with FHSS. Must be <= 65ms.
 #define MAC_TX_PROCESSING_DELAY_INITIAL 2000
+// Give up on data request after given timeout (seconds)
+#define DATA_REQUEST_TIMEOUT_NORMAL_PRIORITY_S  30
+#define DATA_REQUEST_TIMEOUT_EF_PRIORITY_S      120
 
 typedef struct {
     uint8_t address[8];
@@ -275,7 +278,7 @@ void mcps_sap_data_req_handler_ext(protocol_interface_rf_mac_setup_s *rf_mac_set
             }
             break;
         case MAC_DATA_HIGH_PRIORITY:
-            buffer->priority = MAC_PD_DATA_HIGH_PRIOTITY;
+            buffer->priority = MAC_PD_DATA_HIGH_PRIORITY;
             break;
         case MAC_DATA_MEDIUM_PRIORITY:
             buffer->priority = MAC_PD_DATA_MEDIUM_PRIORITY;
@@ -1102,6 +1105,18 @@ static void mac_mcps_asynch_finish(protocol_interface_rf_mac_setup_s *rf_mac_set
     }
 }
 
+static bool mcps_sap_check_buffer_timeout(protocol_interface_rf_mac_setup_s *rf_mac_setup, mac_pre_build_frame_t *buffer)
+{
+    // Convert from 1us slots to seconds
+    uint32_t buffer_age_s = (mac_mcps_sap_get_phy_timestamp(rf_mac_setup) - buffer->request_start_time_us) / 1000000;
+    if ((buffer->priority == MAC_PD_DATA_NORMAL_PRIORITY) && (buffer_age_s > DATA_REQUEST_TIMEOUT_NORMAL_PRIORITY_S)) {
+        return true;
+    } else if ((buffer->priority == MAC_PD_DATA_EF_PRIORITY) && (buffer_age_s > DATA_REQUEST_TIMEOUT_EF_PRIORITY_S)) {
+        return true;
+    }
+    return false;
+}
+
 void mac_mcps_trig_buffer_from_queue(protocol_interface_rf_mac_setup_s *rf_mac_setup)
 {
     if (!rf_mac_setup) {
@@ -1121,22 +1136,31 @@ void mac_mcps_trig_buffer_from_queue(protocol_interface_rf_mac_setup_s *rf_mac_s
         buffer = mcps_sap_pd_req_queue_read(rf_mac_setup, is_bc_queue, false);
 
         if (buffer) {
-            //Here
-            if (buffer->ExtendedFrameExchange) {
-                //Update here state and store peer
-                memcpy(rf_mac_setup->mac_edfe_info->PeerAddr, buffer->DstAddr, 8);
-                rf_mac_setup->mac_edfe_info->state = MAC_EDFE_FRAME_CONNECTING;
-            }
-            rf_mac_setup->active_pd_data_request = buffer;
-            if (mcps_pd_data_request(rf_mac_setup, buffer) != 0) {
+            if (mcps_sap_check_buffer_timeout(rf_mac_setup, buffer)) {
+                // Buffer is quite old. Return it to adaptation layer with timeout event.
+                rf_mac_setup->mac_tx_result = MAC_TX_TIMEOUT;
                 if (buffer->ExtendedFrameExchange) {
                     rf_mac_setup->mac_edfe_info->state = MAC_EDFE_FRAME_IDLE;
                 }
-                rf_mac_setup->active_pd_data_request = NULL;
                 mac_mcps_asynch_finish(rf_mac_setup, buffer);
                 mcps_data_confirm_handle(rf_mac_setup, buffer, NULL);
             } else {
-                return;
+                if (buffer->ExtendedFrameExchange) {
+                    //Update here state and store peer
+                    memcpy(rf_mac_setup->mac_edfe_info->PeerAddr, buffer->DstAddr, 8);
+                    rf_mac_setup->mac_edfe_info->state = MAC_EDFE_FRAME_CONNECTING;
+                }
+                rf_mac_setup->active_pd_data_request = buffer;
+                if (mcps_pd_data_request(rf_mac_setup, buffer) != 0) {
+                    if (buffer->ExtendedFrameExchange) {
+                        rf_mac_setup->mac_edfe_info->state = MAC_EDFE_FRAME_IDLE;
+                    }
+                    rf_mac_setup->active_pd_data_request = NULL;
+                    mac_mcps_asynch_finish(rf_mac_setup, buffer);
+                    mcps_data_confirm_handle(rf_mac_setup, buffer, NULL);
+                } else {
+                    return;
+                }
             }
         } else {
             return;
@@ -2437,10 +2461,16 @@ static mac_pre_build_frame_t *mcps_sap_pd_req_queue_read(protocol_interface_rf_m
 
     mac_pre_build_frame_t *buffer = queue;
     mac_pre_build_frame_t *prev = NULL;
-    // With FHSS, check TX conditions
+    /* With FHSS, read buffer out from queue if:
+     * - Buffer has timed out, OR
+     * - Buffer is asynch request, OR
+     * - Queue is flushed, OR
+     * - Blacklisting AND FHSS allows buffer to be transmitted
+     */
     if (rf_mac_setup->fhss_api) {
         while (buffer) {
-            if (buffer->asynch_request ||
+            if (mcps_sap_check_buffer_timeout(rf_mac_setup, buffer) ||
+                    buffer->asynch_request ||
                     (flush == true) ||
                     ((mcps_check_packet_blacklist(rf_mac_setup, buffer) == false) &&
                      (rf_mac_setup->fhss_api->check_tx_conditions(rf_mac_setup->fhss_api, !mac_is_ack_request_set(buffer),

source/MAC/IEEE802_15_4/mac_mcps_sap.h

@@ -48,7 +48,7 @@ typedef enum {
 
 #define MAC_PD_DATA_NORMAL_PRIORITY 0    //Normal MCPS DATA REQ
 #define MAC_PD_DATA_MEDIUM_PRIORITY 1    //Indirect Data which is polled
-#define MAC_PD_DATA_HIGH_PRIOTITY   2    //Beacon request Beacon response
+#define MAC_PD_DATA_HIGH_PRIORITY   2    //Beacon request Beacon response
 #define MAC_PD_DATA_EF_PRIORITY     3    //Expedited forwarding
 #define MAC_PD_DATA_TX_IMMEDIATELY  4    //Only for packets whose transmission was interrupted by wrong channel type. E.g. unicast on broadcast channel.
 

source/MAC/IEEE802_15_4/mac_mlme.c

@@ -1837,7 +1837,7 @@ int8_t mac_mlme_beacon_tx(protocol_interface_rf_mac_setup_s *rf_ptr)
             ptr += BEACON_OPTION_JOIN_PRIORITY_LEN;
         }*/
     }
-    buf->priority = MAC_PD_DATA_HIGH_PRIOTITY;
+    buf->priority = MAC_PD_DATA_HIGH_PRIORITY;
     mcps_sap_pd_req_queue_write(rf_ptr, buf);
     sw_mac_stats_update(rf_ptr, STAT_MAC_BEA_TX_COUNT, 0);
     return 0;

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

@@ -238,6 +238,27 @@ static  arm_device_driver_list_s *rf_client_driver_allocate()
     return driver;
 }
 
+uint32_t test_timestamp = 1000000;
+static int8_t test_rf_extension(phy_extension_type_e extension, uint8_t *buf)
+{
+    switch (extension) {
+        case PHY_EXTENSION_GET_TIMESTAMP:
+            buf[3] = test_timestamp >> 24;
+            buf[2] = test_timestamp >> 16;
+            buf[1] = test_timestamp >> 8;
+            buf[0] = test_timestamp;
+            test_timestamp += 100000;
+            break;
+        case PHY_EXTENSION_READ_LAST_ACK_PENDING_STATUS:
+            *buf = 1;
+            break;
+        case PHY_EXTENSION_READ_RX_TIME:
+            common_write_32_bit(100, buf);
+        default:
+            break;
+    }
+    return 0;
+}
 
 static protocol_interface_rf_mac_setup_s *test_mac_rf_mac_class_allocate(void)
 {
@@ -261,32 +282,11 @@ static protocol_interface_rf_mac_setup_s *test_mac_rf_mac_class_allocate(void)
     dev_driver->phy_header_length = 0;
     driver->phy_driver = dev_driver;
     rf_mac_setup->dev_driver = driver;
+    rf_mac_setup->dev_driver->phy_driver->extension = test_rf_extension;
 
     return rf_mac_setup;
 }
 
-uint32_t test_timestamp = 1000000;
-static int8_t test_rf_extension(phy_extension_type_e extension, uint8_t *buf)
-{
-    switch (extension) {
-        case PHY_EXTENSION_GET_TIMESTAMP:
-            buf[3] = test_timestamp >> 24;
-            buf[2] = test_timestamp >> 16;
-            buf[1] = test_timestamp >> 8;
-            buf[0] = test_timestamp;
-            test_timestamp += 100000;
-            break;
-        case PHY_EXTENSION_READ_LAST_ACK_PENDING_STATUS:
-            *buf = 1;
-            break;
-        case PHY_EXTENSION_READ_RX_TIME:
-            common_write_32_bit(100, buf);
-        default:
-            break;
-    }
-    return 0;
-}
-
 static int8_t test_rf_tx(uint8_t *data, uint16_t length, uint8_t tx_handle, data_protocol_e protocol)
 {
     return 0;
@@ -3046,6 +3046,93 @@ bool test_mac_mcps_trig_buffer_from_queue()
         return false;
     }
     mac_mcps_buffer_queue_free(rf_mac_setup);
+
+    // Test removing old buffers from queue
+    rf_mac_setup->fhss_api = ns_fhss_create(0, 0, 0);
+    // Add 4 buffers in queue, buf and buf2 are too old and should be removed
+    buf = tes_mac_mcps_temporary_buffer_get(0);
+    buf2 = tes_mac_mcps_temporary_buffer_get(0);
+    mac_pre_build_frame_t *buf3 = tes_mac_mcps_temporary_buffer_get(0);
+    mac_pre_build_frame_t *buf4 = tes_mac_mcps_temporary_buffer_get(0);
+    buf->request_start_time_us = test_timestamp - 32000000;
+    buf2->request_start_time_us = test_timestamp - 31000000;
+    buf3->request_start_time_us = test_timestamp - 25000000;
+    buf4->request_start_time_us = test_timestamp - 23000000;
+    rf_mac_setup->pd_data_request_queue_to_go = buf;
+    rf_mac_setup->pd_data_request_queue_to_go->next = buf2;
+    rf_mac_setup->pd_data_request_queue_to_go->next->next = buf3;
+    rf_mac_setup->pd_data_request_queue_to_go->next->next->next = buf4;
+    rf_mac_setup->unicast_queue_size = 4;
+    fhss_config_stub.bool_value = false;
+    fhss_tx_condition = true;
+    // Trig should remove first two buffers and take third as active data request
+    mac_mcps_trig_buffer_from_queue(rf_mac_setup);
+    if (rf_mac_setup->active_pd_data_request != buf3) {
+        test_mac_rf_mac_class_free(rf_mac_setup);
+        printf("Fail: Remove old buffers, wrong buffer activated\r\n");
+        return false;
+    }
+    mac_mcps_buffer_queue_free(rf_mac_setup);
+
+    // Test removing old buffers with low priority from queue
+    rf_mac_setup->fhss_api = ns_fhss_create(0, 0, 0);
+    // Add 4 buffers in queue, buf and buf2 are too old but only first one should be removed
+    buf = tes_mac_mcps_temporary_buffer_get(0);
+    buf2 = tes_mac_mcps_temporary_buffer_get(0);
+    buf3 = tes_mac_mcps_temporary_buffer_get(0);
+    buf4 = tes_mac_mcps_temporary_buffer_get(0);
+    buf->request_start_time_us = test_timestamp - 32000000;
+    buf2->request_start_time_us = test_timestamp - 31000000;
+    buf3->request_start_time_us = test_timestamp - 25000000;
+    buf4->request_start_time_us = test_timestamp - 23000000;
+    // Change buf2 priority to medium
+    buf2->priority = MAC_PD_DATA_MEDIUM_PRIORITY;
+    rf_mac_setup->pd_data_request_queue_to_go = buf;
+    rf_mac_setup->pd_data_request_queue_to_go->next = buf2;
+    rf_mac_setup->pd_data_request_queue_to_go->next->next = buf3;
+    rf_mac_setup->pd_data_request_queue_to_go->next->next->next = buf4;
+    rf_mac_setup->unicast_queue_size = 4;
+    fhss_config_stub.bool_value = false;
+    fhss_tx_condition = true;
+    // Trig should remove first buffer and take second as active data request
+    mac_mcps_trig_buffer_from_queue(rf_mac_setup);
+    if (rf_mac_setup->active_pd_data_request != buf2) {
+        test_mac_rf_mac_class_free(rf_mac_setup);
+        printf("Fail: Remove old buffers with priority, wrong buffer activated\r\n");
+        return false;
+    }
+    mac_mcps_buffer_queue_free(rf_mac_setup);
+
+    // Test removing old buffers with EF priority from queue
+    rf_mac_setup->fhss_api = ns_fhss_create(0, 0, 0);
+    // Add 4 buffers in queue, buf(normal priority) and buf2(EF priority) are too old and should be removed
+    buf = tes_mac_mcps_temporary_buffer_get(0);
+    buf2 = tes_mac_mcps_temporary_buffer_get(0);
+    buf3 = tes_mac_mcps_temporary_buffer_get(0);
+    buf4 = tes_mac_mcps_temporary_buffer_get(0);
+    buf->request_start_time_us = test_timestamp - 32000000;
+    buf2->request_start_time_us = test_timestamp - 121000000;
+    buf3->request_start_time_us = test_timestamp - 100000000;
+    buf4->request_start_time_us = test_timestamp - 23000000;
+    // Change buf2 and buf3 priority to expedited forwarding
+    buf2->priority = MAC_PD_DATA_EF_PRIORITY;
+    buf3->priority = MAC_PD_DATA_EF_PRIORITY;
+    rf_mac_setup->pd_data_request_queue_to_go = buf;
+    rf_mac_setup->pd_data_request_queue_to_go->next = buf2;
+    rf_mac_setup->pd_data_request_queue_to_go->next->next = buf3;
+    rf_mac_setup->pd_data_request_queue_to_go->next->next->next = buf4;
+    rf_mac_setup->unicast_queue_size = 4;
+    fhss_config_stub.bool_value = false;
+    fhss_tx_condition = true;
+    // Trig should remove first two buffers and take third as active data request
+    mac_mcps_trig_buffer_from_queue(rf_mac_setup);
+    if (rf_mac_setup->active_pd_data_request != buf3) {
+        test_mac_rf_mac_class_free(rf_mac_setup);
+        printf("Fail: Remove old buffers with EF priority, wrong buffer activated\r\n");
+        return false;
+    }
+    mac_mcps_buffer_queue_free(rf_mac_setup);
+
     // Free test setup struct
     test_mac_rf_mac_class_free(rf_mac_setup);
     return true;