sched/semaphore/spinlock.c: spin_trylock handle memory barrier and instrumentation correctly.

include/nuttx/spinlock.h

@@ -208,7 +208,31 @@ void spin_lock_wo_note(FAR volatile spinlock_t *lock);
  *
  ****************************************************************************/
 
-#define spin_trylock(l) up_testset(l)
+spinlock_t spin_trylock(FAR volatile spinlock_t *lock);
+
+/****************************************************************************
+ * Name: spin_trylock_wo_note
+ *
+ * Description:
+ *   Try once to lock the spinlock.  Do not wait if the spinlock is already
+ *   locked.
+ *
+ *   This implementation is the same as the above spin_trylock() except that
+ *   it does not perform instrumentation logic.
+ *
+ * Input Parameters:
+ *   lock - A reference to the spinlock object to lock.
+ *
+ * Returned Value:
+ *   SP_LOCKED   - Failure, the spinlock was already locked
+ *   SP_UNLOCKED - Success, the spinlock was successfully locked
+ *
+ * Assumptions:
+ *   Not running at the interrupt level.
+ *
+ ****************************************************************************/
+
+spinlock_t spin_trylock_wo_note(FAR volatile spinlock_t *lock);
 
 /****************************************************************************
  * Name: spin_unlock

sched/irq/irq_csection.c

@@ -134,7 +134,7 @@ static inline bool irq_waitlock(int cpu)
    * for the deadlock condition.
    */
 
-  while (spin_trylock(&g_cpu_irqlock) == SP_LOCKED)
+  while (spin_trylock_wo_note(&g_cpu_irqlock) == SP_LOCKED)
     {
       /* Is a pause request pending? */
 
@@ -152,8 +152,6 @@ static inline bool irq_waitlock(int cpu)
 
           return false;
         }
-
-      SP_DSB();
     }
 
   /* We have g_cpu_irqlock! */
@@ -164,7 +162,6 @@ static inline bool irq_waitlock(int cpu)
   sched_note_spinlocked(tcb, &g_cpu_irqlock);
 #endif
 
-  SP_DMB();
   return true;
 }
 #endif

sched/semaphore/spinlock.c

@@ -131,6 +131,87 @@ void spin_lock_wo_note(FAR volatile spinlock_t *lock)
   SP_DMB();
 }
 
+/****************************************************************************
+ * Name: spin_trylock
+ *
+ * Description:
+ *   Try once to lock the spinlock.  Do not wait if the spinlock is already
+ *   locked.
+ *
+ * Input Parameters:
+ *   lock - A reference to the spinlock object to lock.
+ *
+ * Returned Value:
+ *   SP_LOCKED   - Failure, the spinlock was already locked
+ *   SP_UNLOCKED - Success, the spinlock was successfully locked
+ *
+ * Assumptions:
+ *   Not running at the interrupt level.
+ *
+ ****************************************************************************/
+
+spinlock_t spin_trylock(FAR volatile spinlock_t *lock)
+{
+#ifdef CONFIG_SCHED_INSTRUMENTATION_SPINLOCKS
+  /* Notify that we are waiting for a spinlock */
+
+  sched_note_spinlock(this_task(), lock);
+#endif
+
+  if (up_testset(lock) == SP_LOCKED)
+    {
+#ifdef CONFIG_SCHED_INSTRUMENTATION_SPINLOCKS
+      /* Notify that we abort for a spinlock */
+
+      sched_note_spinabort(this_task(), &lock);
+#endif
+      SP_DSB();
+      return SP_LOCKED;
+    }
+
+#ifdef CONFIG_SCHED_INSTRUMENTATION_SPINLOCKS
+  /* Notify that we have the spinlock */
+
+  sched_note_spinlocked(this_task(), lock);
+#endif
+  SP_DMB();
+  return SP_UNLOCKED;
+}
+
+/****************************************************************************
+ * Name: spin_trylock_wo_note
+ *
+ * Description:
+ *   Try once to lock the spinlock.  Do not wait if the spinlock is already
+ *   locked.
+ *
+ *   This implementation is the same as the above spin_trylock() except that
+ *   it does not perform instrumentation logic.
+ *
+ * Input Parameters:
+ *   lock - A reference to the spinlock object to lock.
+ *
+ * Returned Value:
+ *   SP_LOCKED   - Failure, the spinlock was already locked
+ *   SP_UNLOCKED - Success, the spinlock was successfully locked
+ *
+ * Assumptions:
+ *   Not running at the interrupt level.
+ *
+ ****************************************************************************/
+
+spinlock_t spin_trylock_wo_note(FAR volatile spinlock_t *lock)
+{
+  if (up_testset(lock) == SP_LOCKED)
+    {
+      SP_DSB();
+      return SP_LOCKED;
+    }
+
+  SP_DMB();
+  return SP_UNLOCKED;
+}
+
 /****************************************************************************
  * Name: spin_unlock
  *