[pause_proc_timer][5/n] ErtsMonitorSuspend can pause the proc timer

We add a flag to the monitor state to indicate that the proc timer is to be
stopped (or was already stopped) and take it into account while suspending
the process.

Nothing sets the new flag yet, that happens in the next commit

erts/emulator/beam/erl_monitor_link.h

@@ -735,7 +735,8 @@ struct ErtsMonitorSuspend__ {
     erts_atomic64_t state;
 };
 #define ERTS_MSUSPEND_STATE_FLG_ACTIVE ((erts_aint64_t) (((Uint64) 1) << 63))
-#define ERTS_MSUSPEND_STATE_COUNTER_MASK (~ERTS_MSUSPEND_STATE_FLG_ACTIVE)
+#define ERTS_MSUSPEND_STATE_FLG_PAUSE_TIMER ((erts_aint64_t) (((Uint64) 1) << 62))
+#define ERTS_MSUSPEND_STATE_COUNTER_MASK (((erts_aint64_t) (((Uint64) 1) << 62)) - 1)
 
 /* 
  * --- Monitor tree operations ---

erts/emulator/beam/erl_proc_sig_queue.c

@@ -4992,6 +4992,19 @@ handle_process_info(Process *c_p, ErtsSigRecvTracing *tracing,
     return ((int) reds)*4 + 8;
 }
 
+static void
+activate_suspend_monitor(Process *c_p, ErtsMonitorSuspend *msp)
+{
+    erts_aint64_t mstate;
+    int pause_proc_timer = 0;
+
+    mstate = erts_atomic64_read_bor_acqb(&msp->state,
+                                         ERTS_MSUSPEND_STATE_FLG_ACTIVE);
+    ASSERT(!(mstate & ERTS_MSUSPEND_STATE_FLG_ACTIVE));
+    pause_proc_timer = !!(mstate & ERTS_MSUSPEND_STATE_FLG_PAUSE_TIMER);
+    erts_suspend(c_p, ERTS_PROC_LOCK_MAIN, NULL, pause_proc_timer);
+}
+
 static void
 handle_suspend(Process *c_p, ErtsMonitor *mon, int *yieldp)
 {
@@ -5000,14 +5013,8 @@ handle_suspend(Process *c_p, ErtsMonitor *mon, int *yieldp)
     ASSERT(mon->type == ERTS_MON_TYPE_SUSPEND);
 
     if (!(state & ERTS_PSFLG_DIRTY_RUNNING)) {
-        ErtsMonitorSuspend *msp;
-        erts_aint64_t mstate;
-
-        msp = (ErtsMonitorSuspend *) erts_monitor_to_data(mon);
-        mstate = erts_atomic64_read_bor_acqb(&msp->state,
-                                             ERTS_MSUSPEND_STATE_FLG_ACTIVE);
-        ASSERT(!(mstate & ERTS_MSUSPEND_STATE_FLG_ACTIVE)); (void) mstate;
-        erts_suspend(c_p, ERTS_PROC_LOCK_MAIN, NULL, 0);
+        ErtsMonitorSuspend *msp = (ErtsMonitorSuspend *) erts_monitor_to_data(mon);
+        activate_suspend_monitor(c_p, msp);
         *yieldp = !0;
     }
     else {
@@ -5207,18 +5214,13 @@ erts_proc_sig_handle_pending_suspend(Process *c_p)
     psusp = (ErtsProcSigPendingSuspend *) ERTS_PROC_GET_PENDING_SUSPEND(c_p);
 
     msp = psusp->mon;
-    
+
     while (msp) {
         ErtsMonitorSuspend *next_msp = msp->next;
         msp->next = NULL;
         if (!(state & ERTS_PSFLG_EXITING)
             && erts_monitor_is_in_table(&msp->md.u.target)) {
-            erts_aint64_t mstate;
-
-            mstate = erts_atomic64_read_bor_acqb(&msp->state,
-                                                 ERTS_MSUSPEND_STATE_FLG_ACTIVE);
-            ASSERT(!(mstate & ERTS_MSUSPEND_STATE_FLG_ACTIVE)); (void) mstate;
-            erts_suspend(c_p, ERTS_PROC_LOCK_MAIN, NULL, 0);
+            activate_suspend_monitor(c_p, msp);
         }
 
         erts_monitor_release(&msp->md.u.target);