2005-08-17 Andrew Sinclair <Andrew.Sinclair@elprotech.com>

	PR 807/rtems
	* rtems/src/timerfireafter.c, rtems/src/timerserverfireafter.c,
	score/src/watchdoginsert.c: Tighten critical section checks on an ISR
	using the same timer being inserted by a lower priority ISR or
	interupt task.

5 files changed, 74 insertions, 6 deletions

diff --git a/cpukit/rtems/ChangeLog b/cpukit/rtems/ChangeLog
index fde6efd0f5..7cfb6f3fc7 100644
--- a/cpukit/rtems/ChangeLog
+++ b/cpukit/rtems/ChangeLog
@@ -1,3 +1,11 @@
+2005-08-17	Andrew Sinclair <Andrew.Sinclair@elprotech.com>
+
+	PR 807/rtems
+	* rtems/src/timerfireafter.c, rtems/src/timerserverfireafter.c,
+	score/src/watchdoginsert.c: Tighten critical section checks on an ISR
+	using the same timer being inserted by a lower priority ISR or
+	interupt task.
+
 2005-05-13      Jennifer Averett <jennifer.averett@oarcorp.com>
 
         PR 786/rtems
diff --git a/cpukit/rtems/src/timerfireafter.c b/cpukit/rtems/src/timerfireafter.c
index 7b4660c82b..76b426b107 100644
--- a/cpukit/rtems/src/timerfireafter.c
+++ b/cpukit/rtems/src/timerfireafter.c
@@ -47,6 +47,7 @@ rtems_status_code rtems_timer_fire_after(
 {
   Timer_Control      *the_timer;
   Objects_Locations   location;
+  ISR_Level           level;
 
   if ( ticks == 0 )
     return RTEMS_INVALID_NUMBER;
@@ -64,8 +65,29 @@ rtems_status_code rtems_timer_fire_after(
 
     case OBJECTS_LOCAL:
       (void) _Watchdog_Remove( &the_timer->Ticker );
-      the_timer->the_class = TIMER_INTERVAL;
-      _Watchdog_Initialize( &the_timer->Ticker, routine, id, user_data );
+
+      _ISR_Disable( level );
+
+        /*
+         *  Check to see if the watchdog has just been inserted by a
+         *  higher priority interrupt.  If so, abandon this insert.
+         */
+
+        if ( the_timer->Ticker.state != WATCHDOG_INACTIVE ) {
+          _ISR_Enable( level );
+          return RTEMS_SUCCESSFUL;
+        }
+
+        /*
+         *  OK.  Now we now the timer was not rescheduled by an interrupt
+         *  so we can atomically initialize it as in use.
+         */
+
+        the_timer->the_class = TIMER_INTERVAL;
+        _Watchdog_Initialize( &the_timer->Ticker, routine, id, user_data );
+      _ISR_Enable( level );
+
+
       _Watchdog_Insert_ticks( &the_timer->Ticker, ticks );
       _Thread_Enable_dispatch();
       return RTEMS_SUCCESSFUL;
diff --git a/cpukit/rtems/src/timerserverfireafter.c b/cpukit/rtems/src/timerserverfireafter.c
index 0074ea4c0c..eff74b49cc 100644
--- a/cpukit/rtems/src/timerserverfireafter.c
+++ b/cpukit/rtems/src/timerserverfireafter.c
@@ -48,6 +48,7 @@ rtems_status_code rtems_timer_server_fire_after(
 {
   Timer_Control        *the_timer;
   Objects_Locations     location;
+  ISR_Level             level;
   extern Chain_Control  _Timer_Ticks_chain;
 
   if ( !_Timer_Server )
@@ -69,9 +70,28 @@ rtems_status_code rtems_timer_server_fire_after(
 
     case OBJECTS_LOCAL:
       (void) _Watchdog_Remove( &the_timer->Ticker );
-      the_timer->the_class = TIMER_INTERVAL_ON_TASK;
-      _Watchdog_Initialize( &the_timer->Ticker, routine, id, user_data );
-      the_timer->Ticker.initial = ticks;
+
+      _ISR_Disable( level );
+
+        /*
+         *  Check to see if the watchdog has just been inserted by a
+         *  higher priority interrupt.  If so, abandon this insert.
+         */
+
+        if ( the_timer->Ticker.state != WATCHDOG_INACTIVE ) {
+          _ISR_Enable( level );
+          return RTEMS_SUCCESSFUL;
+        }
+
+        /*
+         *  OK.  Now we now the timer was not rescheduled by an interrupt
+         *  so we can atomically initialize it as in use.
+         */
+
+        the_timer->the_class = TIMER_INTERVAL_ON_TASK;
+        _Watchdog_Initialize( &the_timer->Ticker, routine, id, user_data );
+        the_timer->Ticker.initial = ticks;
+      _ISR_Enable( level );
 
       _Timer_Server_stop_ticks_timer();
       _Timer_Server_process_ticks_chain();
diff --git a/cpukit/score/ChangeLog b/cpukit/score/ChangeLog
index f1fe0f362c..19ada3cc3e 100644
--- a/cpukit/score/ChangeLog
+++ b/cpukit/score/ChangeLog
@@ -1,3 +1,11 @@
+2005-08-17	Andrew Sinclair <Andrew.Sinclair@elprotech.com>
+
+	PR 807/rtems
+	* rtems/src/timerfireafter.c, rtems/src/timerserverfireafter.c,
+	score/src/watchdoginsert.c: Tighten critical section checks on an ISR
+	using the same timer being inserted by a lower priority ISR or
+	interupt task.
+
 2005-05-13      Jennifer Averett <jennifer.averett@oarcorp.com>
 
         PR 786/rtems    
diff --git a/cpukit/score/src/watchdoginsert.c b/cpukit/score/src/watchdoginsert.c
index 4e921e28c8..5dfea56a46 100644
--- a/cpukit/score/src/watchdoginsert.c
+++ b/cpukit/score/src/watchdoginsert.c
@@ -36,10 +36,20 @@ void _Watchdog_Insert(
   
 
   insert_isr_nest_level   = _ISR_Nest_level;
-  the_watchdog->state = WATCHDOG_BEING_INSERTED;
 
   _ISR_Disable( level );
 
+  /*
+   *  Check to see if the watchdog has just been inserted by a
+   *  higher priority interrupt.  If so, abandon this insert.
+   */
+
+  if ( the_watchdog->state != WATCHDOG_INACTIVE ) {
+    _ISR_Enable( level );
+    return;
+  }
+
+  the_watchdog->state = WATCHDOG_BEING_INSERTED;
   _Watchdog_Sync_count++;
 
 restart: