score: Optimize watchdog tickle

Avoid unnecessary lock acquire/release operations.  Get realtime via
timecounter only if necessary.

Update #3264.

1 files changed, 22 insertions, 2 deletions

diff --git a/cpukit/score/src/coretodset.c b/cpukit/score/src/coretodset.c
index fa6407cfaf..787c263643 100644
--- a/cpukit/score/src/coretodset.c
+++ b/cpukit/score/src/coretodset.c
@@ -41,9 +41,29 @@ void _TOD_Set(
   cpu_count = _SMP_Get_processor_count();
 
   for ( cpu_index = 0 ; cpu_index < cpu_count ; ++cpu_index ) {
-    Per_CPU_Control *cpu = _Per_CPU_Get_by_index( cpu_index );
+    Per_CPU_Control  *cpu;
+    Watchdog_Header  *header;
+    ISR_lock_Context  lock_context;
+    Watchdog_Control *first;
 
-    _Watchdog_Per_CPU_tickle_realtime( cpu, tod_as_ticks );
+    cpu = _Per_CPU_Get_by_index( cpu_index );
+    header = &cpu->Watchdog.Header[ PER_CPU_WATCHDOG_REALTIME ];
+
+    _ISR_lock_ISR_disable_and_acquire( &cpu->Watchdog.Lock, &lock_context );
+
+    first = _Watchdog_Header_first( header );
+
+    if ( first != NULL ) {
+      _Watchdog_Tickle(
+        header,
+        first,
+        tod_as_ticks,
+        &cpu->Watchdog.Lock,
+        &lock_context
+      );
+    }
+
+    _ISR_lock_Release_and_ISR_enable( &cpu->Watchdog.Lock, &lock_context );
   }
 
   _TOD.is_set = true;