Added ETX to rpl_possible_better_candidate

ETX may be 0 when it is new neighbour and then etx is optimistic 128.

Change-Id: Ic5ed0d453d04a16ead9d040217cd132b5d35e366

Author: Juha Heiskanen

source/6LoWPAN/ws/ws_bootstrap.c

@@ -2147,10 +2147,17 @@ static bool ws_rpl_new_parent_callback(uint8_t *ll_parent_address, void *handle,
     }
 
     uint8_t replacing[16];
-    uint8_t mac64[8];
+    uint8_t mac64[10];
     bool replace_ok = false;
     bool create_ok = false;
     llc_neighbour_req_t neigh_buffer;
+
+    //Discover neigh ready here for possible ETX validate
+    memcpy(mac64, ll_parent_address + 8, 8);
+    mac64[0] ^= 2;
+
+    ws_bootstrap_neighbor_info_request(cur, mac64, &neigh_buffer, false);
+
     if (rpl_control_candidate_list_size(cur, instance) < cur->ws_info->rpl_parent_candidate_max) {
         //Not reach max value yet accept then all go to create neigh table
         goto neigh_create;
@@ -2161,20 +2168,22 @@ static bool ws_rpl_new_parent_callback(uint8_t *ll_parent_address, void *handle,
         return false;
     }
 
-    // if not yet probed, return false
-    memcpy(mac64, replacing + 8, 8);
-    mac64[0] ^= 2;
+    // +2 Is for PAN ID space
+    memcpy(mac64 + 2, replacing + 8, 8);
+    mac64[2] ^= 2;
 
-    if (ws_bootstrap_neighbor_info_request(cur, mac64, &neigh_buffer, false)) {
-        //Verify that we have proped min 1 time
-        etx_storage_t *etx_entry = etx_storage_entry_get(cur->id, neigh_buffer.neighbor->index);
-        if (etx_entry && etx_entry->etx_samples == 0) {
-            return false;
-        }
+    if (ws_etx_read(cur, ADDR_802_15_4_LONG, mac64) == 0xffff) {
+        //Not proped yet because ETX is 0xffff
+        return false;
+    }
+
+    uint16_t etx = 0;
+    if (neigh_buffer.neighbor) {
+        etx = etx_local_etx_read(cur->id, neigh_buffer.neighbor->index);
     }
 
     // Accept now only better one's when max candidates slected and max candidate list size is reached
-    if (!rpl_possible_better_candidate(cur, instance, replacing, candidate_rank)) {
+    if (!rpl_possible_better_candidate(cur, instance, replacing, candidate_rank, etx)) {
         return false;
     }
     //TODO if replacing has poor ETX, put it in blacklist as "poor ETX" to prevent reselection
@@ -2183,14 +2192,16 @@ static bool ws_rpl_new_parent_callback(uint8_t *ll_parent_address, void *handle,
 
 neigh_create:
 
-    memcpy(mac64, ll_parent_address + 8, 8);
-    mac64[0] ^= 2;
-    if (ws_bootstrap_neighbor_info_request(cur, mac64, &neigh_buffer, false)) {
+
+    if (neigh_buffer.neighbor) {
+        //Use Already discovered entry
         create_ok = true;
         goto neigh_create_ok;
     }
 
-    //Discover Multicast temporary entry
+    //Discover Multicast temporary entry for create neighbour table entry for new candidate
+    memcpy(mac64, ll_parent_address + 8, 8);
+    mac64[0] ^= 2;
     ws_neighbor_temp_class_t *entry = ws_llc_get_multicast_temp_entry(cur, mac64);
     if (!entry) {
         return false;

source/RPL/rpl_control.c

@@ -272,7 +272,7 @@ bool rpl_control_probe_parent_candidate(protocol_interface_info_entry_t *interfa
     return false;
 }
 
-bool rpl_possible_better_candidate(struct protocol_interface_info_entry *interface, rpl_instance_t *rpl_instance, const uint8_t ll_addr[16], uint16_t candidate_rank)
+bool rpl_possible_better_candidate(struct protocol_interface_info_entry *interface, rpl_instance_t *rpl_instance, const uint8_t ll_addr[16], uint16_t candidate_rank, uint16_t etx)
 {
     if (!interface->rpl_domain) {
         return false;
@@ -283,7 +283,7 @@ bool rpl_possible_better_candidate(struct protocol_interface_info_entry *interfa
         return false;
     }
 
-    return rpl_instance_possible_better_candidate(rpl_instance, neighbour, candidate_rank);
+    return rpl_instance_possible_better_candidate(rpl_instance, neighbour, candidate_rank, etx);
 
 }
 
@@ -1847,9 +1847,8 @@ void rpl_control_print(route_print_fn_t *print_fn)
     unsigned s = s_full % 60;
     unsigned h = m / 60;
     m %= 60;
-    print_fn("Time %02u:%02u:%02u.%u (%u.%u)", h, m, s, t, s_full, t);
     // %zu doesn't work on some Mbed toolchains
-    print_fn("RPL memory usage %" PRIu32, (uint32_t) rpl_alloc_total);
+    print_fn("Time %02u:%02u:%02u.%u (%u.%u) RPL memory usage %" PRIu32, h, m, s, t, s_full, t, (uint32_t) rpl_alloc_total);
     ns_list_foreach(rpl_domain_t, domain, &rpl_domains) {
         rpl_domain_print(domain, print_fn);
     }

source/RPL/rpl_control.h

@@ -155,7 +155,7 @@ void rpl_control_unpublish_address(rpl_domain_t *domain, const uint8_t addr[16])
 bool rpl_control_is_dodag_parent(struct protocol_interface_info_entry *interface, const uint8_t ll_addr[16]);
 bool rpl_control_is_dodag_parent_candidate(struct protocol_interface_info_entry *interface, const uint8_t ll_addr[16], uint16_t candidate_cmp_limiter);
 bool rpl_control_probe_parent_candidate(struct protocol_interface_info_entry *interface, const uint8_t ll_addr[16]);
-bool rpl_possible_better_candidate(struct protocol_interface_info_entry *interface, struct rpl_instance *rpl_instance, const uint8_t ll_addr[16], uint16_t candidate_rank);
+bool rpl_possible_better_candidate(struct protocol_interface_info_entry *interface, struct rpl_instance *rpl_instance, const uint8_t ll_addr[16], uint16_t candidate_rank, uint16_t etx);
 uint16_t rpl_control_parent_candidate_list_size(struct protocol_interface_info_entry *interface, bool parent_list);
 uint16_t rpl_control_candidate_list_size(struct protocol_interface_info_entry *interface, struct rpl_instance *rpl_instance);
 void rpl_control_neighbor_delete(struct protocol_interface_info_entry *interface, const uint8_t ll_addr[16]);

source/RPL/rpl_mrhof.c

@@ -45,7 +45,7 @@
 static void rpl_mrhof_parent_selection(rpl_instance_t *instance);
 static uint16_t rpl_mrhof_path_cost_through_neighbour(const rpl_neighbour_t *neighbour);
 static bool rpl_mrhof_neighbour_acceptable(const rpl_instance_t *instance, const rpl_neighbour_t *neighbour);
-static bool rpl_mrhof_possible_better_candidate(const rpl_instance_t *instance, const rpl_neighbour_t *existing, uint16_t rank);
+static bool rpl_mrhof_possible_better_candidate(const rpl_instance_t *instance, const rpl_neighbour_t *existing, uint16_t rank, uint16_t etx);
 
 static rpl_objective_t rpl_mrhof = {
     .ocp = RPL_OCP_MRHOF,
@@ -96,7 +96,7 @@ static bool rpl_mrhof_neighbour_acceptable(const rpl_instance_t *instance, const
     return rpl_mrhof_link_metric_to_neighbour(neighbour) <= rpl_policy_mrhof_max_link_metric(instance->domain);
 }
 
-static bool rpl_mrhof_possible_better_candidate(const rpl_instance_t *instance, const rpl_neighbour_t *existing, uint16_t rank)
+static bool rpl_mrhof_possible_better_candidate(const rpl_instance_t *instance, const rpl_neighbour_t *existing, uint16_t rank, uint16_t etx)
 {
     uint16_t existing_path = rpl_mrhof_path_cost_through_neighbour(existing);
     // Optimistically assume we could get a perfect link to this new person
@@ -105,7 +105,15 @@ static bool rpl_mrhof_possible_better_candidate(const rpl_instance_t *instance,
     // Think: could actually use rpl_mrhof_etx here to get an existing ETX estimate
     // (except that gives infinite if no current link, would want a variant that checks
     // blacklist records for remembered poor ETX)
-    uint16_t potential_path_with_hysteresis = rpl_rank_add(rank, 128 + rpl_policy_mrhof_parent_switch_threshold(instance->domain));
+    uint16_t threshold = rpl_policy_mrhof_parent_switch_threshold(instance->domain);
+    if (etx == 0) {
+        etx = 128;
+    } else if (etx >= (0xffff - threshold)) {
+        return false;
+    }
+
+    etx += threshold;
+    uint16_t potential_path_with_hysteresis = rpl_rank_add(rank, etx);
     return potential_path_with_hysteresis <= existing_path;
 }
 

source/RPL/rpl_objective.h

@@ -33,7 +33,7 @@ typedef struct rpl_objective {
     bool (*neighbour_acceptable)(const struct rpl_instance *, const struct rpl_neighbour *);
     /* Could someone with specified rank be a significantly better candidate than the existing one? */
     /* (In future, this API could be extended to pass a metric pointer as well as rank) */
-    bool (*possible_better_candidate)(const struct rpl_instance *, const struct rpl_neighbour *existing, uint16_t rank);
+    bool (*possible_better_candidate)(const struct rpl_instance *, const struct rpl_neighbour *existing, uint16_t rank, uint16_t etx);
     ns_list_link_t link;
 } rpl_objective_t;
 

source/RPL/rpl_of0.c

@@ -42,7 +42,7 @@
 static void rpl_of0_parent_selection(rpl_instance_t *instance);
 static uint16_t rpl_of0_rank_through_neighbour(const rpl_neighbour_t *neighbour);
 static bool rpl_of0_neighbour_acceptable(const rpl_instance_t *instance, const rpl_neighbour_t *neighbour);
-static bool rpl_of0_possible_better_candidate(const rpl_instance_t *instance, const rpl_neighbour_t *existing, uint16_t rank);
+static bool rpl_of0_possible_better_candidate(const rpl_instance_t *instance, const rpl_neighbour_t *existing, uint16_t rank, uint16_t etx);
 
 static rpl_objective_t rpl_of0 = {
     .ocp = RPL_OCP_OF0,
@@ -117,8 +117,9 @@ static uint16_t rpl_of0_rank_through_neighbour(const rpl_neighbour_t *neighbour)
     return rpl_rank_add(neighbour->rank, rpl_of0_rank_increase(neighbour));
 }
 
-static bool rpl_of0_possible_better_candidate(const rpl_instance_t *instance, const rpl_neighbour_t *existing, uint16_t rank)
+static bool rpl_of0_possible_better_candidate(const rpl_instance_t *instance, const rpl_neighbour_t *existing, uint16_t rank, uint16_t etx)
 {
+    (void)etx;
     uint16_t existing_path = rpl_of0_rank_through_neighbour(existing);
     uint16_t potential_path_with_hysteresis = rpl_rank_add(rank, 2 * rpl_policy_of0_rank_factor(instance->domain) * existing->dodag_version->dodag->config.min_hop_rank_increase);
     return potential_path_with_hysteresis <= existing_path;

source/RPL/rpl_upward.c

@@ -290,9 +290,9 @@ uint16_t rpl_instance_candidate_rank(const rpl_neighbour_t *candidate)
     return candidate->rank;
 }
 
-bool rpl_instance_possible_better_candidate(const rpl_instance_t *instance, rpl_neighbour_t *replacing, uint16_t candidate_rank)
+bool rpl_instance_possible_better_candidate(const rpl_instance_t *instance, rpl_neighbour_t *replacing, uint16_t candidate_rank, uint16_t etx)
 {
-    return instance->of->possible_better_candidate(instance, replacing, candidate_rank);
+    return instance->of->possible_better_candidate(instance, replacing, candidate_rank, etx);
 }
 
 /* If we're a member of a DODAG Version matching the predicate in this instance,

source/RPL/rpl_upward.h

@@ -70,7 +70,7 @@ bool rpl_instance_am_root(const rpl_instance_t *instance);
 uint8_t rpl_instance_mop(const rpl_instance_t *instance);
 rpl_dodag_version_t *rpl_instance_current_dodag_version(const rpl_instance_t *instance);
 rpl_neighbour_t *rpl_instance_preferred_parent(const rpl_instance_t *instance);
-bool rpl_instance_possible_better_candidate(const rpl_instance_t *instance, rpl_neighbour_t *replacing, uint16_t candidate_rank);
+bool rpl_instance_possible_better_candidate(const rpl_instance_t *instance, rpl_neighbour_t *replacing, uint16_t candidate_rank, uint16_t etx);
 rpl_dodag_version_t *rpl_instance_predicate_match(rpl_instance_t *instance, uint8_t pred, uint8_t instance_id, const uint8_t *dodagid, uint8_t version_num);
 void rpl_instance_inconsistency(rpl_instance_t *instance);
 void rpl_instance_consistent_rx(rpl_instance_t *instance);

test/nanostack/unittest/stub/rpl_control_stub.c

@@ -269,7 +269,7 @@ bool rpl_control_probe_parent_candidate(protocol_interface_info_entry_t *interfa
     return false;
 }
 
-bool rpl_possible_better_candidate(struct protocol_interface_info_entry *interface, struct rpl_instance *rpl_instance, const uint8_t ll_addr[16], uint16_t candidate_rank)
+bool rpl_possible_better_candidate(struct protocol_interface_info_entry *interface, struct rpl_instance *rpl_instance, const uint8_t ll_addr[16], uint16_t candidate_rank, uint16_t etx)
 {
     return true;
 }

test/nanostack/unittest/stub/rpl_upward_stub.c

@@ -503,4 +503,9 @@ uint16_t rpl_instance_candidate_rank(const rpl_neighbour_t *candidate)
     return 0xffff;
 }
 
+bool rpl_instance_possible_better_candidate(const rpl_instance_t *instance, rpl_neighbour_t *replacing, uint16_t candidate_rank, uint16_t etx)
+{
+    return false;
+}
+
 #endif /* HAVE_RPL */