Abort when aux work runs on a dirty scheduler

While the system will keep working, the aux work will never run
and the affected scheduler never goes to sleep. OTP-15446 is a
good example of this.

As this error easily flies under the radar it's best to make it
immediately visible. The assertions we had in debug builds were
clearly not enough to catch all sources of this problem.

1 files changed, 13 insertions, 10 deletions

diff --git a/erts/emulator/beam/erl_process.c b/erts/emulator/beam/erl_process.c
index a21acb9a57..1dde9800f8 100644
--- a/erts/emulator/beam/erl_process.c
+++ b/erts/emulator/beam/erl_process.c
@@ -3284,7 +3284,12 @@ scheduler_wait(int *fcalls, ErtsSchedulerData *esdp, ErtsRunQueue *rq)
         ErtsMonotonicTime current_time = 0;
 
         aux_work = erts_atomic32_read_acqb(&ssi->aux_work);
-        if (aux_work && !ERTS_SCHEDULER_IS_DIRTY(esdp)) {
+
+        if (aux_work && ERTS_SCHEDULER_IS_DIRTY(esdp)) {
+            ERTS_INTERNAL_ERROR("Executing aux work on a dirty scheduler.");
+        }
+
+        if (aux_work) {
             if (!thr_prgr_active) {
                 erts_thr_progress_active(esdp, thr_prgr_active = 1);
                 sched_wall_time_change(esdp, 1);
@@ -3296,16 +3301,14 @@ scheduler_wait(int *fcalls, ErtsSchedulerData *esdp, ErtsRunQueue *rq)
         }
 
         if (aux_work) {
-            if (!ERTS_SCHEDULER_IS_DIRTY(esdp)) {
-                flgs = erts_atomic32_read_acqb(&ssi->flags);
-                current_time = erts_get_monotonic_time(esdp);
-                if (current_time >= erts_next_timeout_time(esdp->next_tmo_ref)) {
-                    if (!thr_prgr_active) {
-                        erts_thr_progress_active(esdp, thr_prgr_active = 1);
-                        sched_wall_time_change(esdp, 1);
-                    }
-                    erts_bump_timers(esdp->timer_wheel, current_time);
+            flgs = erts_atomic32_read_acqb(&ssi->flags);
+            current_time = erts_get_monotonic_time(esdp);
+            if (current_time >= erts_next_timeout_time(esdp->next_tmo_ref)) {
+                if (!thr_prgr_active) {
+                    erts_thr_progress_active(esdp, thr_prgr_active = 1);
+                    sched_wall_time_change(esdp, 1);
                 }
+                erts_bump_timers(esdp->timer_wheel, current_time);
             }
         }
         else {