Merge branch 'rickard/alloc-opt/OTP-7775'

* rickard/alloc-opt/OTP-7775:
  Fix erts_thr_progress_wakeup()

1 files changed, 23 insertions, 8 deletions

diff --git a/erts/emulator/beam/erl_thr_progress.c b/erts/emulator/beam/erl_thr_progress.c
index 9324bcde51..02f36fc75e 100644
--- a/erts/emulator/beam/erl_thr_progress.c
+++ b/erts/emulator/beam/erl_thr_progress.c
@@ -80,12 +80,12 @@
 
 #ifdef ERTS_SMP
 
-/*
- * We use a 64-bit value for thread progress. By this wrapping of
- * the thread progress will more or less never occur.
- *
- * On 32-bit systems we therefore need a double word atomic.
- */
+#define ERTS_THR_PRGR_DBG_CHK_WAKEUP_REQUEST_VALUE 0
+
+#ifdef DEBUG
+#undef ERTS_THR_PRGR_DBG_CHK_WAKEUP_REQUEST_VALUE
+#define ERTS_THR_PRGR_DBG_CHK_WAKEUP_REQUEST_VALUE 1
+#endif
 
 #define ERTS_THR_PRGR_PRINT_LEADER 0
 #define ERTS_THR_PRGR_PRINT_VAL 0
@@ -106,6 +106,13 @@
 		 |ERTS_THR_PRGR_LFLG_ACTIVE_MASK)) \
      == ERTS_THR_PRGR_LFLG_NO_LEADER)
 
+/*
+ * We use a 64-bit value for thread progress. By this wrapping of
+ * the thread progress will more or less never occur.
+ *
+ * On 32-bit systems we therefore need a double word atomic.
+ */
+
 #define read_acqb erts_thr_prgr_read_acqb__
 
 #ifdef ARCH_64
@@ -937,8 +944,10 @@ request_wakeup_managed(ErtsThrPrgrData *tpd, ErtsThrPrgrVal value)
     ASSERT(tpd->is_managed);
     ASSERT(tpd->previous.local != ERTS_THR_PRGR_VAL_WAITING);
 
-    if (has_reached_wakeup(value))
+    if (has_reached_wakeup(value)) {
 	wakeup_managed(tpd->id);
+	return;
+    }
 
     wix = ERTS_THR_PRGR_WAKEUP_IX(value);
     if (tpd->wakeup_request[wix] == value)
@@ -976,6 +985,10 @@ request_wakeup_managed(ErtsThrPrgrData *tpd, ErtsThrPrgrVal value)
     mwd = intrnl->managed.data[wix];
 
     ix = erts_atomic32_inc_read_nob(&mwd->len) - 1;
+#if ERTS_THR_PRGR_DBG_CHK_WAKEUP_REQUEST_VALUE
+    if (ix >= intrnl->managed.no)
+	erl_exit(ERTS_ABORT_EXIT, "Internal error: Too many wakeup requests\n");
+#endif
     mwd->id[ix] = tpd->id;
 
     ASSERT(!erts_thr_progress_has_reached(value));
@@ -1001,8 +1014,10 @@ request_wakeup_unmanaged(ErtsThrPrgrData *tpd, ErtsThrPrgrVal value)
      * we are writing the request.
      */
 
-    if (has_reached_wakeup(value))
+    if (has_reached_wakeup(value)) {
 	wakeup_unmanaged(tpd->id);
+	return;
+    }
 
     wix = ERTS_THR_PRGR_WAKEUP_IX(value);