nr pdcp: introduce a thread to do pdcp_data_ind

Before this commit, pdcp_data_ind is done in the realtime PHY/MAC
thread, and this may have an impact on realtime performances.

Let's introduce a new thread to do the job, freeing the realtime
PHY/MAC logic.

This is not a minor change. It may have positive and/or negative
effects. To be tested carefully.

openair2/LAYER2/nr_pdcp/nr_pdcp_oai_api.c

@@ -215,6 +215,182 @@ void du_rlc_data_req(const protocol_ctxt_t *const ctxt_pP,
 /* rlc_data_req queue - end                                                 */
 /****************************************************************************/
 
+/****************************************************************************/
+/* pdcp_data_ind thread - begin                                             */
+/****************************************************************************/
+
+typedef struct {
+  protocol_ctxt_t ctxt_pP;
+  srb_flag_t      srb_flagP;
+  MBMS_flag_t     MBMS_flagP;
+  rb_id_t         rb_id;
+  sdu_size_t      sdu_buffer_size;
+  mem_block_t     *sdu_buffer;
+} pdcp_data_ind_queue_item;
+
+#define PDCP_DATA_IND_QUEUE_SIZE 10000
+
+typedef struct {
+  pdcp_data_ind_queue_item q[PDCP_DATA_IND_QUEUE_SIZE];
+  volatile int start;
+  volatile int length;
+  pthread_mutex_t m;
+  pthread_cond_t c;
+} pdcp_data_ind_queue;
+
+static pdcp_data_ind_queue pq;
+
+static void do_pdcp_data_ind(
+  const protocol_ctxt_t *const  ctxt_pP,
+  const srb_flag_t srb_flagP,
+  const MBMS_flag_t MBMS_flagP,
+  const rb_id_t rb_id,
+  const sdu_size_t sdu_buffer_size,
+  mem_block_t *const sdu_buffer)
+{
+  nr_pdcp_ue_t *ue;
+  nr_pdcp_entity_t *rb;
+  int rnti = ctxt_pP->rnti;
+
+  if (ctxt_pP->module_id != 0 ||
+      //ctxt_pP->enb_flag != 1 ||
+      ctxt_pP->instance != 0 ||
+      ctxt_pP->eNB_index != 0 ||
+      ctxt_pP->configured != 1 ||
+      ctxt_pP->brOption != 0) {
+    LOG_E(PDCP, "%s:%d:%s: fatal\n", __FILE__, __LINE__, __FUNCTION__);
+    exit(1);
+  }
+
+  if (ctxt_pP->enb_flag)
+    T(T_ENB_PDCP_UL, T_INT(ctxt_pP->module_id), T_INT(rnti),
+      T_INT(rb_id), T_INT(sdu_buffer_size));
+
+  nr_pdcp_manager_lock(nr_pdcp_ue_manager);
+  ue = nr_pdcp_manager_get_ue(nr_pdcp_ue_manager, rnti);
+
+  if (srb_flagP == 1) {
+    if (rb_id < 1 || rb_id > 2)
+      rb = NULL;
+    else
+      rb = ue->srb[rb_id - 1];
+  } else {
+    if (rb_id < 1 || rb_id > 5)
+      rb = NULL;
+    else
+      rb = ue->drb[rb_id - 1];
+  }
+
+  if (rb != NULL) {
+    rb->recv_pdu(rb, (char *)sdu_buffer->data, sdu_buffer_size);
+  } else {
+    LOG_E(PDCP, "%s:%d:%s: fatal: no RB found (rb_id %ld, srb_flag %d)\n",
+          __FILE__, __LINE__, __FUNCTION__, rb_id, srb_flagP);
+    exit(1);
+  }
+
+  nr_pdcp_manager_unlock(nr_pdcp_ue_manager);
+
+  free_mem_block(sdu_buffer, __FUNCTION__);
+}
+
+static void *pdcp_data_ind_thread(void *_)
+{
+  int i;
+
+  pthread_setname_np(pthread_self(), "PDCP data ind");
+  while (1) {
+    if (pthread_mutex_lock(&pq.m) != 0) abort();
+    while (pq.length == 0)
+      if (pthread_cond_wait(&pq.c, &pq.m) != 0) abort();
+    i = pq.start;
+    if (pthread_mutex_unlock(&pq.m) != 0) abort();
+
+    do_pdcp_data_ind(&pq.q[i].ctxt_pP,
+                     pq.q[i].srb_flagP,
+                     pq.q[i].MBMS_flagP,
+                     pq.q[i].rb_id,
+                     pq.q[i].sdu_buffer_size,
+                     pq.q[i].sdu_buffer);
+
+    if (pthread_mutex_lock(&pq.m) != 0) abort();
+
+    pq.length--;
+    pq.start = (pq.start + 1) % PDCP_DATA_IND_QUEUE_SIZE;
+
+    if (pthread_cond_signal(&pq.c) != 0) abort();
+    if (pthread_mutex_unlock(&pq.m) != 0) abort();
+  }
+}
+
+static void init_nr_pdcp_data_ind_queue(void)
+{
+  pthread_t t;
+
+  pthread_mutex_init(&pq.m, NULL);
+  pthread_cond_init(&pq.c, NULL);
+
+  if (pthread_create(&t, NULL, pdcp_data_ind_thread, NULL) != 0) {
+    LOG_E(PDCP, "%s:%d:%s: fatal\n", __FILE__, __LINE__, __FUNCTION__);
+    exit(1);
+  }
+}
+
+static void enqueue_pdcp_data_ind(
+  const protocol_ctxt_t *const  ctxt_pP,
+  const srb_flag_t srb_flagP,
+  const MBMS_flag_t MBMS_flagP,
+  const rb_id_t rb_id,
+  const sdu_size_t sdu_buffer_size,
+  mem_block_t *const sdu_buffer)
+{
+  int i;
+  int logged = 0;
+
+  if (pthread_mutex_lock(&pq.m) != 0) abort();
+  while (pq.length == PDCP_DATA_IND_QUEUE_SIZE) {
+    if (!logged) {
+      logged = 1;
+      LOG_W(PDCP, "%s: pdcp_data_ind queue is full\n", __FUNCTION__);
+    }
+    if (pthread_cond_wait(&pq.c, &pq.m) != 0) abort();
+  }
+
+  i = (pq.start + pq.length) % PDCP_DATA_IND_QUEUE_SIZE;
+  pq.length++;
+
+  pq.q[i].ctxt_pP         = *ctxt_pP;
+  pq.q[i].srb_flagP       = srb_flagP;
+  pq.q[i].MBMS_flagP      = MBMS_flagP;
+  pq.q[i].rb_id           = rb_id;
+  pq.q[i].sdu_buffer_size = sdu_buffer_size;
+  pq.q[i].sdu_buffer      = sdu_buffer;
+
+  if (pthread_cond_signal(&pq.c) != 0) abort();
+  if (pthread_mutex_unlock(&pq.m) != 0) abort();
+}
+
+boolean_t pdcp_data_ind(
+  const protocol_ctxt_t *const  ctxt_pP,
+  const srb_flag_t srb_flagP,
+  const MBMS_flag_t MBMS_flagP,
+  const rb_id_t rb_id,
+  const sdu_size_t sdu_buffer_size,
+  mem_block_t *const sdu_buffer)
+{
+  enqueue_pdcp_data_ind(ctxt_pP,
+                        srb_flagP,
+                        MBMS_flagP,
+                        rb_id,
+                        sdu_buffer_size,
+                        sdu_buffer);
+  return true;
+}
+
+/****************************************************************************/
+/* pdcp_data_ind thread - end                                               */
+/****************************************************************************/
+
 /****************************************************************************/
 /* hacks to be cleaned up at some point - begin                             */
 /****************************************************************************/
@@ -375,6 +551,7 @@ void pdcp_layer_init(void)
     init_nr_rlc_data_req_queue();
   }
 
+  init_nr_pdcp_data_ind_queue();
   nr_pdcp_init_timer_thread(nr_pdcp_ue_manager);
 }
 
@@ -639,62 +816,6 @@ srb_found:
   }
 }
 
-boolean_t pdcp_data_ind(
-  const protocol_ctxt_t *const  ctxt_pP,
-  const srb_flag_t srb_flagP,
-  const MBMS_flag_t MBMS_flagP,
-  const rb_id_t rb_id,
-  const sdu_size_t sdu_buffer_size,
-  mem_block_t *const sdu_buffer)
-{
-  nr_pdcp_ue_t *ue;
-  nr_pdcp_entity_t *rb;
-  int rnti = ctxt_pP->rnti;
-
-  if (ctxt_pP->module_id != 0 ||
-      //ctxt_pP->enb_flag != 1 ||
-      ctxt_pP->instance != 0 ||
-      ctxt_pP->eNB_index != 0 ||
-      ctxt_pP->configured != 1 ||
-      ctxt_pP->brOption != 0) {
-    LOG_E(PDCP, "%s:%d:%s: fatal\n", __FILE__, __LINE__, __FUNCTION__);
-    exit(1);
-  }
-
-  if (ctxt_pP->enb_flag)
-    T(T_ENB_PDCP_UL, T_INT(ctxt_pP->module_id), T_INT(rnti),
-      T_INT(rb_id), T_INT(sdu_buffer_size));
-
-  nr_pdcp_manager_lock(nr_pdcp_ue_manager);
-  ue = nr_pdcp_manager_get_ue(nr_pdcp_ue_manager, rnti);
-
-  if (srb_flagP == 1) {
-    if (rb_id < 1 || rb_id > 2)
-      rb = NULL;
-    else
-      rb = ue->srb[rb_id - 1];
-  } else {
-    if (rb_id < 1 || rb_id > 5)
-      rb = NULL;
-    else
-      rb = ue->drb[rb_id - 1];
-  }
-
-  if (rb != NULL) {
-    rb->recv_pdu(rb, (char *)sdu_buffer->data, sdu_buffer_size);
-  } else {
-    LOG_E(PDCP, "%s:%d:%s: fatal: no RB found (rb_id %ld, srb_flag %d)\n",
-          __FILE__, __LINE__, __FUNCTION__, rb_id, srb_flagP);
-    exit(1);
-  }
-
-  nr_pdcp_manager_unlock(nr_pdcp_ue_manager);
-
-  free_mem_block(sdu_buffer, __FUNCTION__);
-
-  return 1;
-}
-
 void pdcp_run(const protocol_ctxt_t *const  ctxt_pP)
 {
   MessageDef      *msg_p;