diff --git a/include/haproxy/task-t.h b/include/haproxy/task-t.h
index 5debef652..62252e748 100644
--- a/include/haproxy/task-t.h
+++ b/include/haproxy/task-t.h
@@ -56,7 +56,8 @@
                            TASK_WOKEN_RES)
 
 #define TASK_F_TASKLET    0x00008000  /* nature of this task: 0=task 1=tasklet */
-/* unused: 0x10000..0x80000000 */
+#define TASK_F_USR1       0x00010000  /* preserved user flag 1, application-specific, def:0 */
+/* unused: 0x20000..0x80000000 */
 
 
 enum {
diff --git a/src/task.c b/src/task.c
index a99d30ab6..bc8ecf4cf 100644
--- a/src/task.c
+++ b/src/task.c
@@ -487,7 +487,7 @@ unsigned int run_tasks_from_lists(unsigned int budgets[])
 
 		budgets[queue]--;
 		t = (struct task *)LIST_ELEM(tl_queues[queue].n, struct tasklet *, list);
-		state = t->state & (TASK_SHARED_WQ|TASK_SELF_WAKING|TASK_HEAVY|TASK_F_TASKLET|TASK_KILLED);
+		state = t->state & (TASK_SHARED_WQ|TASK_SELF_WAKING|TASK_HEAVY|TASK_F_TASKLET|TASK_KILLED|TASK_F_USR1);
 
 		ti->flags &= ~TI_FL_STUCK; // this thread is still running
 		activity[tid].ctxsw++;
@@ -533,7 +533,7 @@ unsigned int run_tasks_from_lists(unsigned int budgets[])
 
 		LIST_DEL_INIT(&((struct tasklet *)t)->list);
 		__ha_barrier_store();
-		state = _HA_ATOMIC_XCHG(&t->state, state | TASK_RUNNING);
+		state = _HA_ATOMIC_XCHG(&t->state, state|TASK_RUNNING|TASK_F_USR1);
 		__ha_barrier_atomic_store();
 
 		/* OK then this is a regular task */