unqueue_matching: Add max_depth argument

Look only at the last `max_depth` items on the queue, at most.

openair2/PHY_INTERFACE/phy_stub_UE.c

@@ -1084,8 +1084,14 @@ int memcpy_dl_config_req(L1_rxtx_proc_t *proc,
             req->sfn_sf >> 4, req->sfn_sf & 15);
       return 0;
     }
-    dlsch_pdu_indicies_t wanted = {num_dlsch_pdu_indicies, dlsch_pdu_indicies};
-    nfapi_tx_req_pdu_list_t *matched = unqueue_matching(&tx_req_pdu_queue, match_dl_config_req, &wanted);
+    dlsch_pdu_indicies_t wanted =
+    {
+      num_dlsch_pdu_indicies,
+      dlsch_pdu_indicies,
+    };
+    nfapi_tx_req_pdu_list_t *matched =
+      unqueue_matching(&tx_req_pdu_queue, /*max_depth=*/ 2,
+                       match_dl_config_req, &wanted);
     if (!matched)
     {
       LOG_W(MAC, "Could not unqueue_matching\n");

openair2/PHY_INTERFACE/queue.c

@@ -113,7 +113,7 @@ void *unqueue(queue_t *q)
     return item;
 }
 
-void *unqueue_matching(queue_t *q, queue_matcher_t *matcher, void *wanted)
+void *unqueue_matching(queue_t *q, size_t max_depth, queue_matcher_t *matcher, void *wanted)
 {
     if (pthread_mutex_lock(&q->mutex) != 0)
     {
@@ -125,6 +125,12 @@ void *unqueue_matching(queue_t *q, queue_matcher_t *matcher, void *wanted)
     size_t endi = q->write_index;
     for (size_t i = 0; i < q->num_items; i++)
     {
+        if (max_depth == 0)
+        {
+            break;
+        }
+        --max_depth;
+
         endi = (endi + MAX_QUEUE_SIZE - 1) % MAX_QUEUE_SIZE;
         void *candidate = q->items[endi];
         if (matcher(wanted, candidate))

openair2/PHY_INTERFACE/queue.h

@@ -55,7 +55,8 @@ void *unqueue(queue_t *q);
 
 typedef bool queue_matcher_t(void *wanted, void *candidate);
 
-/* Unqueue the most recently queued item for watch `matcher(wanted, candidate)`
+/* Unqueue the most recently queued item for which `matcher(wanted, candidate)`
    returns true where `candidate` is an item currently on the queue.
+   Look only at the last `max_depth` items on the queue, at most.
    Returns the candidate item, or NULL if none matches */
-void *unqueue_matching(queue_t *q, queue_matcher_t *matcher, void *wanted);
+void *unqueue_matching(queue_t *q, size_t max_depth, queue_matcher_t *matcher, void *wanted);

openair2/PHY_INTERFACE/queue_test.c

@@ -128,7 +128,7 @@ int main(void)
     init_queue(&queue);
 
     // empty queue
-    p = unqueue_matching(&queue, matcher, &thing1);
+    p = unqueue_matching(&queue, MAX_QUEUE_SIZE, matcher, &thing1);
     EQUAL(p, NULL);
     EQUAL(queue.num_items, 0);
 
@@ -136,14 +136,19 @@ int main(void)
     if (!put_queue(&queue, &thing1))
         FAIL;
     EQUAL(queue.num_items, 1);
-    p = unqueue_matching(&queue, matcher, &thing2);
+    p = unqueue_matching(&queue, MAX_QUEUE_SIZE, matcher, &thing2);
     EQUAL(p, NULL);
     EQUAL(queue.num_items, 1);
-    p = unqueue_matching(&queue, matcher, &thing1);
+
+    p = unqueue_matching(&queue, /*max_queue=*/ 0, matcher, &thing1);
+    EQUAL(p, NULL);
+    EQUAL(queue.num_items, 1);
+
+    p = unqueue_matching(&queue, /*max_queue=*/ 1, matcher, &thing1);
     EQUAL(p, &thing1);
     EQUAL(queue.num_items, 0);
 
-    // fill the queue then remove every other item
+    // more max_queue values
     for (int i = 0; i < MAX_QUEUE_SIZE; ++i)
     {
         if (!put_queue(&queue, &things[i]))
@@ -151,15 +156,35 @@ int main(void)
             FAIL;
         }
     }
-    p = unqueue_matching(&queue, matcher, &thing1);
+    p = unqueue_matching(&queue, /*max_queue=*/ 0, matcher, &things[MAX_QUEUE_SIZE - 1]);
+    EQUAL(p, NULL);
+    p = unqueue_matching(&queue, /*max_queue=*/ 1, matcher, &things[MAX_QUEUE_SIZE - 1]);
+    EQUAL(p, &things[MAX_QUEUE_SIZE - 1]);
+    EQUAL(queue.num_items, MAX_QUEUE_SIZE - 1);
+    p = unqueue_matching(&queue, /*max_queue=*/ MAX_QUEUE_SIZE - 2, matcher, &things[0]);
+    EQUAL(p, NULL);
+    p = unqueue_matching(&queue, /*max_queue=*/ MAX_QUEUE_SIZE - 1, matcher, &things[0]);
+    EQUAL(p, &things[0]);
+    EQUAL(queue.num_items, MAX_QUEUE_SIZE - 2);
+
+    // fill the queue then remove every other item
+    init_queue(&queue);
+    for (int i = 0; i < MAX_QUEUE_SIZE; ++i)
+    {
+        if (!put_queue(&queue, &things[i]))
+        {
+            FAIL;
+        }
+    }
+    p = unqueue_matching(&queue, MAX_QUEUE_SIZE, matcher, &thing1);
     EQUAL(p, NULL);
     for (int i = MAX_QUEUE_SIZE - 1; i >= 0; i -= 2)
     {
-        p = unqueue_matching(&queue, matcher, &things[i]);
+        p = unqueue_matching(&queue, MAX_QUEUE_SIZE, matcher, &things[i]);
         EQUAL(p, &things[i]);
     }
     EQUAL(queue.num_items, MAX_QUEUE_SIZE / 2);
-    p = unqueue_matching(&queue, matcher, &thing1);
+    p = unqueue_matching(&queue, MAX_QUEUE_SIZE, matcher, &thing1);
     EQUAL(p, NULL);
     for (int i = 0; i < MAX_QUEUE_SIZE; i += 2)
     {
@@ -176,15 +201,15 @@ int main(void)
             FAIL;
         }
     }
-    p = unqueue_matching(&queue, matcher, &thing1);
+    p = unqueue_matching(&queue, MAX_QUEUE_SIZE, matcher, &thing1);
     EQUAL(p, NULL);
     for (int i = 0; i < MAX_QUEUE_SIZE; i += 3)
     {
-        p = unqueue_matching(&queue, matcher, &things[i]);
+        p = unqueue_matching(&queue, MAX_QUEUE_SIZE, matcher, &things[i]);
         EQUAL(p, &things[i]);
     }
     EQUAL(queue.num_items, MAX_QUEUE_SIZE * 2 / 3);
-    p = unqueue_matching(&queue, matcher, &thing1);
+    p = unqueue_matching(&queue, MAX_QUEUE_SIZE, matcher, &thing1);
     EQUAL(p, NULL);
     for (int i = 0; i < MAX_QUEUE_SIZE; ++i)
     {