scheduler: refactor round-robin loop
authorBrian Norris <banorris@uci.edu>
Sat, 16 Feb 2013 02:22:49 +0000 (18:22 -0800)
committerBrian Norris <banorris@uci.edu>
Sat, 16 Feb 2013 02:36:11 +0000 (18:36 -0800)
This is the same computation, represented more clearly as a for loop
which, if it reaches the completion condition, means that it did not
find an enabled thread.

schedule.cc

index 6d7b63d..e874903 100644 (file)
@@ -190,22 +190,21 @@ Thread * Scheduler::select_next_thread()
                thread_id_t tid = int_to_id(i);
                if (n->has_priority(tid)) {
                        DEBUG("Node (tid %d) has priority\n", i);
-                       //Have a thread with priority
                        if (enabled[i] != THREAD_DISABLED)
                                have_enabled_thread_with_priority = true;
                }
        }
 
-       while (true) {
-               curr_thread_index = (curr_thread_index + 1) % enabled_len;
+       for (int i = 0; i < enabled_len; i++) {
+               curr_thread_index = (old_curr_thread + i + 1) % enabled_len;
                thread_id_t curr_tid = int_to_id(curr_thread_index);
                if (enabled[curr_thread_index] == THREAD_ENABLED &&
                                (!have_enabled_thread_with_priority || n->has_priority(curr_tid))) {
                        return model->get_thread(curr_tid);
                }
-               if (curr_thread_index == old_curr_thread)
-                       return NULL;
        }
+       /* No thread was enabled */
+       return NULL;
 }
 
 /**