Insert at the head of RunQ, to execute timer first.

Author: winlinvip

common.h

@@ -299,6 +299,7 @@ extern _st_eventsys_t *_st_eventsys;
 #define _ST_DEL_IOQ(_pq)    ST_REMOVE_LINK(&_pq.links)
 
 #define _ST_ADD_RUNQ(_thr)  ST_APPEND_LINK(&(_thr)->links, &_ST_RUNQ)
+#define _ST_INSERT_RUNQ(_thr)  ST_INSERT_LINK(&(_thr)->links, &_ST_RUNQ)
 #define _ST_DEL_RUNQ(_thr)  ST_REMOVE_LINK(&(_thr)->links)
 
 #define _ST_ADD_SLEEPQ(_thr, _timeout)  _st_add_sleep_q(_thr, _timeout)

sched.c

@@ -548,7 +548,8 @@ void _st_vp_check_clock(void)
         /* Make thread runnable */
         ST_ASSERT(!(thread->flags & _ST_FL_IDLE_THREAD));
         thread->state = _ST_ST_RUNNABLE;
-        _ST_ADD_RUNQ(thread);
+        // Insert at the head of RunQ, to execute timer first.
+        _ST_INSERT_RUNQ(thread);
     }
 }