GSN-EDF & Core: improve debug TRACE'ing for NP sectionswip-bbb

1 files changed, 5 insertions, 1 deletions

diff --git a/include/litmus/litmus.h b/include/litmus/litmus.h
index 28fb7b331cf3..31ac72eddef7 100644
--- a/include/litmus/litmus.h
+++ b/include/litmus/litmus.h
@@ -178,6 +178,7 @@ static inline int take_np(struct task_struct *t)
 static inline int request_exit_np_atomic(struct task_struct *t)
 {
         union np_flag old, new;
+        int ok;
 
         if (tsk_rt(t)->ctrl_page) {
                 old.raw = tsk_rt(t)->ctrl_page->sched.raw;
@@ -186,17 +187,20 @@ static inline int request_exit_np_atomic(struct task_struct *t)
                         return 0;
                 } else if (old.np.preempt) {
                         /* already set, nothing for us to do */
+                        TRACE_TASK(t, "not setting np.preempt flag again\n");
                         return 1;
                 } else {
                         /* non preemptive and flag not set */
                         new.raw = old.raw;
                         new.np.preempt = 1;
                         /* if we get old back, then we atomically set the flag */
-                        return cmpxchg(&tsk_rt(t)->ctrl_page->sched.raw, old.raw, new.raw) == old.raw;
+                        ok = cmpxchg(&tsk_rt(t)->ctrl_page->sched.raw, old.raw, new.raw) == old.raw;
                         /* If we raced with a concurrent change, then so be
                          * it. Deliver it by IPI.  We don't want an unbounded
                          * retry loop here since tasks might exploit that to
                          * keep the kernel busy indefinitely. */
+                        TRACE_TASK(t,  "request_exit_np => %d\n", ok);
+                        return ok;
                 }
         } else
                 return 0;