There is no need to update exp_start several times for the same worker

src/sched_policies/deque_modeling_policy_data_aware.c

@@ -389,6 +389,13 @@ static int _dm_push_task(struct starpu_task *task, unsigned prio, unsigned sched
 		unsigned memory_node = starpu_worker_get_memory_node(worker);
 		enum starpu_perf_archtype perf_arch = starpu_worker_get_perf_archtype(worker);
 
+		/* Sometimes workers didn't take the tasks as early as we expected */
+		_STARPU_PTHREAD_MUTEX_LOCK(sched_mutex);
+		fifo->exp_start = STARPU_MAX(fifo->exp_start, starpu_timing_now());
+		fifo->exp_end = fifo->exp_start + fifo->exp_len;
+		_STARPU_PTHREAD_MUTEX_UNLOCK(sched_mutex);
+
+
 		for (nimpl = 0; nimpl < STARPU_MAXIMPLEMENTATIONS; nimpl++)
 		{
 			if (!starpu_worker_can_execute_task(worker, task, nimpl))
@@ -403,13 +410,6 @@ static int _dm_push_task(struct starpu_task *task, unsigned prio, unsigned sched
 			starpu_pthread_cond_t *sched_cond;
 			starpu_worker_get_sched_condition(worker, &sched_mutex, &sched_cond);
 
-			/* Sometimes workers didn't take the tasks as early as we expected */
-			_STARPU_PTHREAD_MUTEX_LOCK(sched_mutex);
-			fifo->exp_start = STARPU_MAX(fifo->exp_start, starpu_timing_now());
-			fifo->exp_end = fifo->exp_start + fifo->exp_len;
-			_STARPU_PTHREAD_MUTEX_UNLOCK(sched_mutex);
-
-
 			double local_length = starpu_task_expected_length(task, perf_arch, nimpl);
 			double local_penalty = starpu_task_expected_data_transfer_time(memory_node, task);
 			double ntasks_end = fifo->ntasks / starpu_worker_get_relative_speedup(perf_arch);
@@ -510,6 +510,10 @@ static void compute_all_performance_predictions(struct starpu_task *task,
 		enum starpu_perf_archtype perf_arch = starpu_worker_get_perf_archtype(worker);
 		unsigned memory_node = starpu_worker_get_memory_node(worker);
 
+		_STARPU_PTHREAD_MUTEX_LOCK(sched_mutex);
+		fifo->exp_start = STARPU_MAX(fifo->exp_start, starpu_timing_now());
+		_STARPU_PTHREAD_MUTEX_UNLOCK(sched_mutex);
+
 		for(nimpl  = 0; nimpl < STARPU_MAXIMPLEMENTATIONS; nimpl++)
 	 	{
 			if (!starpu_worker_can_execute_task(worker, task, nimpl))
@@ -524,9 +528,6 @@ static void compute_all_performance_predictions(struct starpu_task *task,
 			starpu_worker_get_sched_condition(worker, &sched_mutex, &sched_cond);
 
 			STARPU_ASSERT_MSG(fifo != NULL, "worker %d ctx %d\n", worker, sched_ctx_id);
-			_STARPU_PTHREAD_MUTEX_LOCK(sched_mutex);
-			fifo->exp_start = STARPU_MAX(fifo->exp_start, starpu_timing_now());
-			_STARPU_PTHREAD_MUTEX_UNLOCK(sched_mutex);
 			exp_end[worker_ctx][nimpl] = fifo->exp_start + fifo->exp_len;
 			if (exp_end[worker_ctx][nimpl] > max_exp_end)
 				max_exp_end = exp_end[worker_ctx][nimpl];