--- libaitsched/inc/aitsched.h	2026/05/19 15:53:56	1.35
+++ libaitsched/inc/aitsched.h	2026/05/20 04:04:10	1.35.2.3
@@ -3,7 +3,7 @@
 *  by Michael Pounov <misho@openbsd-bg.org>
 *
 * $Author: misho $
-* $Id: aitsched.h,v 1.35 2026/05/19 15:53:56 misho Exp $
+* $Id: aitsched.h,v 1.35.2.3 2026/05/20 04:04:10 misho Exp $
 *
 **************************************************************************
 The ELWIX and AITNET software is distributed under the following
@@ -57,8 +57,15 @@ SUCH DAMAGE.
 #ifdef EVFILT_LIO
 #include <aio.h>
 #endif
+#ifdef ATOMIC_SUPPORT
+#ifndef __cplusplus
+        #include <stdatomic.h>
+#else
+        #include <atomic>
+        #define _Atomic(X) std::atomic<X>
+#endif
+#endif
 
-
 /* criteria type */
 #define CRITERIA_ANY	0
 #define CRITERIA_CALL	1
@@ -165,9 +172,15 @@ typedef void *(*sched_task_func_t)(sched_task_t * /* c
 #define SCHED_TASK_DEFINE(x)	void *(x)(sched_task_t*)
 
 /* task lock helpers */
-#define TASK_LOCK(x)		((x)->task_lock = 42)
-#define TASK_UNLOCK(x)		((x)->task_lock ^= (x)->task_lock)
-#define TASK_ISLOCKED(x)	((x)->task_lock)
+#ifdef ATOMIC_SUPPORT
+	#define TASK_LOCK(x)		atomic_store_explicit(&(x)->task_lock, 42, memory_order_release)
+	#define TASK_UNLOCK(x)		atomic_store_explicit(&(x)->task_lock, 0, memory_order_release)
+	#define TASK_ISLOCKED(x)	atomic_load_explicit(&(x)->task_lock, memory_order_acquire)
+#else
+	#define TASK_LOCK(x)		((x)->task_lock = 42)
+	#define TASK_UNLOCK(x)		((x)->task_lock ^= (x)->task_lock)
+	#define TASK_ISLOCKED(x)	((x)->task_lock)
+#endif
 
 /* task & queue */
 struct sched_Task {
@@ -175,7 +188,11 @@ struct sched_Task {
 #define TASK_ID(x)	((struct sched_Task*) (x)->task_id)
 	sched_task_type_t		task_type;
 #define TASK_TYPE(x)	(x)->task_type
+#ifdef ATOMIC_SUPPORT
+	atomic_int			task_lock;
+#else
 	volatile int			task_lock;
+#endif
 
 	sched_root_task_t		*task_root;
 #define TASK_ROOT(x)	(x)->task_root