diff --git a/include/ke/sched.h b/include/ke/sched.h
index 9005de2..32856e4 100644
--- a/include/ke/sched.h
+++ b/include/ke/sched.h
@@ -61,8 +61,8 @@ extern const char *PsPrioClassesNames[];
 // Re-scheduling and preemption
 // XXX atomic operations
 //
-#define PsRequestReSched()     (++KeCurCPU->needReSched)
-#define PsDisablePreemption()  (++KeCurCPU->preemptCount)
+#define PsRequestReSched()     do { ++KeCurCPU->needReSched; } while (0)
+#define PsDisablePreemption()  do { ++KeCurCPU->preemptCount; } while (0)
 #define PsEnablePreemption()   do { assert(KeCurCPU->preemptCount > 0); \
                                     --KeCurCPU->preemptCount; } while(0)