kern: perform rescheduling on dispatch re-enable (closes #1169)

libraries/libmesosphere/include/mesosphere/kern_k_scheduler.hpp

@@ -48,6 +48,7 @@ namespace ams::kern {
         private:
             friend class KScopedSchedulerLock;
             friend class KScopedSchedulerLockAndSleep;
+            friend class KScopedDisableDispatch;
         private:
             SchedulingState state;
             bool is_active;
@@ -161,8 +162,9 @@ namespace ams::kern {
             }
 
             ALWAYS_INLINE void ScheduleOnInterrupt() {
-                KScopedDisableDispatch dd;
+                GetCurrentThread().DisableDispatch();
                 this->Schedule();
+                GetCurrentThread().EnableDispatch();
             }
 
             void RescheduleOtherCores(u64 cores_needing_scheduling);

libraries/libmesosphere/include/mesosphere/kern_k_thread.hpp

@@ -559,20 +559,7 @@ namespace ams::kern {
                 GetCurrentThread().DisableDispatch();
             }
 
-            ALWAYS_INLINE ~KScopedDisableDispatch() {
-                GetCurrentThread().EnableDispatch();
-            }
-    };
-
-    class KScopedEnableDispatch {
-        public:
-            explicit ALWAYS_INLINE KScopedEnableDispatch() {
-                GetCurrentThread().EnableDispatch();
-            }
-
-            ALWAYS_INLINE ~KScopedEnableDispatch() {
-                GetCurrentThread().DisableDispatch();
-            }
+            ~KScopedDisableDispatch();
     };
 
     ALWAYS_INLINE KExceptionContext *GetExceptionContext(KThread *thread) {