sched: Replace direct semaphore value access with nxsem_get_value

Signed-off-by: Jukka Laitinen <jukka.laitinen@tii.ae>

Author: jlaitine

sched/signal/sig_default.c

@@ -303,6 +303,8 @@ static void nxsig_stop_task(int signo)
 
   if ((group->tg_waitflags & WUNTRACED) != 0)
     {
+      int semvalue;
+
       /* Return zero for exit status (we are not exiting, however) */
 
       if (group->tg_statloc != NULL)
@@ -319,11 +321,13 @@ static void nxsig_stop_task(int signo)
 
       /* Wakeup any tasks waiting for this task to exit or stop. */
 
-      while (group->tg_exitsem.semcount < 0)
+      nxsem_get_value(&group->tg_exitsem, &semvalue);
+      while (semvalue < 0)
         {
           /* Wake up the thread */
 
           nxsem_post(&group->tg_exitsem);
+          nxsem_get_value(&group->tg_exitsem, &semvalue);
         }
     }
 #endif

sched/task/task_exithook.c

@@ -315,6 +315,7 @@ static inline void nxtask_signalparent(FAR struct tcb_s *ctcb, int status)
 static inline void nxtask_exitwakeup(FAR struct tcb_s *tcb, int status)
 {
   FAR struct task_group_s *group = tcb->group;
+  int semvalue;
 
   /* Have we already left the group? */
 
@@ -360,11 +361,13 @@ static inline void nxtask_exitwakeup(FAR struct tcb_s *tcb, int status)
           group->tg_statloc   = NULL;
           group->tg_waitflags = 0;
 
-          while (group->tg_exitsem.semcount < 0)
+          nxsem_get_value(&group->tg_exitsem, &semvalue);
+          while (semvalue < 0)
             {
               /* Wake up the thread */
 
               nxsem_post(&group->tg_exitsem);
+              nxsem_get_value(&group->tg_exitsem, &semvalue);
             }
         }
     }