mtapi_c: changed task state attribute to atomic

mtapi_network_c: signaling of task completion is now atomic

mtapi_c/src/embb_mtapi_scheduler_t.c

@@ -302,7 +302,7 @@ int embb_mtapi_scheduler_worker(void * arg) {
             node->queue_pool, task->queue);
       }
 
-      switch (task->state) {
+      switch (embb_atomic_load_int(&task->state)) {
       case MTAPI_TASK_SCHEDULED:
       /* multi-instance task, another instance might be running */
       case MTAPI_TASK_RUNNING:
@@ -398,10 +398,11 @@ mtapi_boolean_t embb_mtapi_scheduler_wait_for_task(
     node->scheduler);
 
   /* now wait and schedule new tasks if we are on a worker */
+  mtapi_task_state_t task_state = embb_atomic_load_int(&task->state);
   while (
-    (MTAPI_TASK_SCHEDULED == task->state) ||
-    (MTAPI_TASK_RUNNING == task->state) ||
-    (MTAPI_TASK_RETAINED == task->state) ) {
+    (MTAPI_TASK_SCHEDULED == task_state) ||
+    (MTAPI_TASK_RUNNING == task_state) ||
+    (MTAPI_TASK_RETAINED == task_state) ) {
     if (MTAPI_INFINITE < timeout) {
       embb_time_t current_time;
       embb_time_now(&current_time);
@@ -416,6 +417,8 @@ mtapi_boolean_t embb_mtapi_scheduler_wait_for_task(
       node->scheduler,
       node,
       context);
+
+    task_state = embb_atomic_load_int(&task->state);
   }
 
   return MTAPI_TRUE;

mtapi_c/src/embb_mtapi_task_context_t.c

@@ -187,7 +187,7 @@ mtapi_task_state_t mtapi_context_taskstate_get(
         &(task_context->thread_context->tss_id));
 
     if (local_context == task_context->thread_context) {
-      task_state = task_context->task->state;
+      task_state = embb_atomic_load_int(&task_context->task->state);
       local_status = MTAPI_SUCCESS;
     } else {
       local_status = MTAPI_ERR_CONTEXT_OUTOFCONTEXT;

mtapi_c/src/embb_mtapi_task_t.c

@@ -79,7 +79,7 @@ void embb_mtapi_task_initialize(embb_mtapi_task_t* that) {
 
   that->action.id = EMBB_MTAPI_IDPOOL_INVALID_ID;
   that->job.id = EMBB_MTAPI_IDPOOL_INVALID_ID;
-  that->state = MTAPI_TASK_ERROR;
+  embb_atomic_store_int(&that->state, MTAPI_TASK_ERROR);
   that->task_id = MTAPI_TASK_ID_NONE;
   that->group.id = EMBB_MTAPI_IDPOOL_INVALID_ID;
   that->queue.id = EMBB_MTAPI_IDPOOL_INVALID_ID;
@@ -159,7 +159,7 @@ void embb_mtapi_task_set_state(
   assert(MTAPI_NULL != that);
 
   embb_spin_lock(&that->state_lock);
-  that->state = state;
+  embb_atomic_store_int(&that->state, state);
   embb_atomic_memory_barrier();
   embb_spin_unlock(&that->state_lock);
 }

mtapi_c/src/embb_mtapi_task_t.h

@@ -66,7 +66,7 @@ struct embb_mtapi_task_struct {
 
   mtapi_action_hndl_t action;
   embb_spinlock_t state_lock;
-  volatile mtapi_task_state_t state;
+  embb_atomic_int state;
   embb_atomic_unsigned_int current_instance;
   embb_atomic_unsigned_int instances_todo;
 

mtapi_network_c/src/embb_mtapi_network.c

@@ -377,7 +377,7 @@ static int embb_mtapi_network_thread(void * args) {
               assert(err == results_size);
 
               local_task->error_code = (mtapi_status_t)task_status;
-              local_task->state = MTAPI_TASK_COMPLETED;
+              embb_atomic_store_int(&local_task->state, MTAPI_TASK_COMPLETED);
               embb_atomic_fetch_and_add_int(&local_action->num_tasks, -1);
 
               /* is task associated with a group? */
@@ -530,7 +530,7 @@ static void network_task_start(
         assert(err == send_buf->size);
 
         embb_atomic_fetch_and_add_int(&local_action->num_tasks, 1);
-        local_task->state = MTAPI_TASK_RUNNING;
+        embb_atomic_store_int(&local_task->state, MTAPI_TASK_RUNNING);
 
         embb_mtapi_network_buffer_clear(send_buf);