smp: Add and use _Assert_Owner_of_giant()

Add and use _ISR_Disable_without_giant() and
_ISR_Enable_without_giant() if RTEMS_SMP is defined.

On single processor systems the ISR disable/enable was the big hammer
which ensured system-wide mutual exclusion.  On SMP configurations this
no longer works since other processors do not care about disabled
interrupts on this processor and continue to execute freely.

On SMP in addition to ISR disable/enable an SMP lock must be used.
Currently we have only the Giant lock so we can check easily that ISR
disable/enable is used only in the right context.

3 files changed, 27 insertions, 13 deletions

diff --git a/cpukit/score/src/smp.c b/cpukit/score/src/smp.c
index 6020b94c46..2f8a488474 100644
--- a/cpukit/score/src/smp.c
+++ b/cpukit/score/src/smp.c
@@ -75,7 +75,7 @@ void rtems_smp_process_interrupt( void )
     #endif
 
     if ( ( message & RTEMS_BSP_SMP_SHUTDOWN ) != 0 ) {
-      _ISR_Disable( level );
+      _ISR_Disable_without_giant( level );
 
       _Thread_Dispatch_set_disable_level( 0 );
 
diff --git a/cpukit/score/src/threaddispatch.c b/cpukit/score/src/threaddispatch.c
index 3b5fb429cf..0c8298f15f 100644
--- a/cpukit/score/src/threaddispatch.c
+++ b/cpukit/score/src/threaddispatch.c
@@ -35,7 +35,7 @@ void _Thread_Dispatch( void )
   ISR_Level         level;
 
 #if defined( RTEMS_SMP )
-  _ISR_Disable( level );
+  _ISR_Disable_without_giant( level );
 #endif
 
   per_cpu = _Per_CPU_Get();
@@ -43,7 +43,7 @@ void _Thread_Dispatch( void )
   per_cpu->thread_dispatch_disable_level = 1;
 
 #if defined( RTEMS_SMP )
-  _ISR_Enable( level );
+  _ISR_Enable_without_giant( level );
 #endif
 
   /*
diff --git a/cpukit/score/src/threaddispatchdisablelevel.c b/cpukit/score/src/threaddispatchdisablelevel.c
index 30755349b2..a3dec9998c 100644
--- a/cpukit/score/src/threaddispatchdisablelevel.c
+++ b/cpukit/score/src/threaddispatchdisablelevel.c
@@ -17,6 +17,7 @@
 
 #include <rtems/score/threaddispatch.h>
 #include <rtems/score/assert.h>
+#include <rtems/score/sysstate.h>
 
 #define NO_OWNER_CPU 0xffffffffU
 
@@ -63,7 +64,7 @@ uint32_t _Thread_Dispatch_increment_disable_level( void )
   uint32_t disable_level;
   Per_CPU_Control *self_cpu;
 
-  _ISR_Disable( isr_level );
+  _ISR_Disable_without_giant( isr_level );
 
   /*
    * We must obtain the processor ID after interrupts are disabled to prevent
@@ -78,7 +79,7 @@ uint32_t _Thread_Dispatch_increment_disable_level( void )
   ++disable_level;
   self_cpu->thread_dispatch_disable_level = disable_level;
 
-  _ISR_Enable( isr_level );
+  _ISR_Enable_without_giant( isr_level );
 
   return disable_level;
 }
@@ -89,7 +90,7 @@ uint32_t _Thread_Dispatch_decrement_disable_level( void )
   uint32_t disable_level;
   Per_CPU_Control *self_cpu;
 
-  _ISR_Disable( isr_level );
+  _ISR_Disable_without_giant( isr_level );
 
   self_cpu = _Per_CPU_Get();
   disable_level = self_cpu->thread_dispatch_disable_level;
@@ -97,8 +98,9 @@ uint32_t _Thread_Dispatch_decrement_disable_level( void )
   self_cpu->thread_dispatch_disable_level = disable_level;
 
   _Giant_Do_release();
+  _Assert( disable_level != 0 || _Giant.owner_cpu == NO_OWNER_CPU );
 
-  _ISR_Enable( isr_level );
+  _ISR_Enable_without_giant( isr_level );
 
   return disable_level;
 }
@@ -118,9 +120,9 @@ uint32_t _Thread_Dispatch_set_disable_level(uint32_t value)
   ISR_Level isr_level;
   uint32_t disable_level;
 
-  _ISR_Disable( isr_level );
+  _ISR_Disable_without_giant( isr_level );
   disable_level = _Thread_Dispatch_disable_level;
-  _ISR_Enable( isr_level );
+  _ISR_Enable_without_giant( isr_level );
 
   /*
    * If we need the dispatch level to go higher 
@@ -147,18 +149,30 @@ void _Giant_Acquire( void )
 {
   ISR_Level isr_level;
 
-  _ISR_Disable( isr_level );
+  _ISR_Disable_without_giant( isr_level );
   _Assert( _Thread_Dispatch_disable_level != 0 );
   _Giant_Do_acquire( _SMP_Get_current_processor() );
-  _ISR_Enable( isr_level );
+  _ISR_Enable_without_giant( isr_level );
 }
 
 void _Giant_Release( void )
 {
   ISR_Level isr_level;
 
-  _ISR_Disable( isr_level );
+  _ISR_Disable_without_giant( isr_level );
   _Assert( _Thread_Dispatch_disable_level != 0 );
   _Giant_Do_release();
-  _ISR_Enable( isr_level );
+  _ISR_Enable_without_giant( isr_level );
 }
+
+#if defined( RTEMS_DEBUG )
+void _Assert_Owner_of_giant( void )
+{
+  Giant_Control *giant = &_Giant;
+
+  _Assert(
+    giant->owner_cpu == _SMP_Get_current_processor()
+      || !_System_state_Is_up( _System_state_Get() )
+  );
+}
+#endif