---
cpukit/score/include/rtems/score/threaddispatch.h | 12 ++++++++++++
cpukit/score/src/smp.c | 8 ++++++++
cpukit/score/src/threaddispatchdisablelevel.c | 13 +++++++++++++
3 files changed, 33 insertions(+), 0 deletions(-)
diff --git a/cpukit/score/include/rtems/score/threaddispatch.h
b/cpukit/score/include/rtems/score/threaddispatch.h
index 2211662..4c2ecb0 100644
--- a/cpukit/score/include/rtems/score/threaddispatch.h
+++ b/cpukit/score/include/rtems/score/threaddispatch.h
@@ -109,6 +109,18 @@ RTEMS_INLINE_ROUTINE void _Thread_Dispatch_initialization(
void )
void _Giant_Release( void );
/**
+ * @brief Releases the giant lock completely if held by the executing
processor.
+ *
+ * The thread dispatch disable level is not altered by this function.
+ *
+ * The only use case for this operation is in
+ * _SMP_Request_processors_to_shutdown().
+ *
+ * @param[in] self_cpu The current processor index.
+ */
+ void _Giant_Drop( uint32_t self_cpu );
+
+ /**
* @brief Sets thread dispatch level to the value passed in.
*
* This routine sets thread dispatch level to the
diff --git a/cpukit/score/src/smp.c b/cpukit/score/src/smp.c
index 445a56a..41787e3 100644
--- a/cpukit/score/src/smp.c
+++ b/cpukit/score/src/smp.c
@@ -115,6 +115,14 @@ void _SMP_Request_processors_to_shutdown( void )
_Per_CPU_Change_state( per_cpu, PER_CPU_STATE_SHUTDOWN );
}
}
+
+ /*
+ * We have to drop the Giant lock here in order to give other processors the
+ * opportunity to receive the inter-processor interrupts issued previously.
+ * In case the executing thread still holds SMP locks, then other processors
+ * already waiting for this SMP lock will spin forever.
+ */
+ _Giant_Drop( self );
}
void _SMP_Send_message( uint32_t cpu, uint32_t message )
diff --git a/cpukit/score/src/threaddispatchdisablelevel.c
b/cpukit/score/src/threaddispatchdisablelevel.c
index a3dec99..ec5ac81 100644
--- a/cpukit/score/src/threaddispatchdisablelevel.c
+++ b/cpukit/score/src/threaddispatchdisablelevel.c
@@ -57,6 +57,19 @@ static void _Giant_Do_release( void )
}
}
+void _Giant_Drop( uint32_t self_cpu )
+{
+ Giant_Control *giant = &_Giant;
+
+ _Assert( _ISR_Get_level() != 0 );
+
+ if ( giant->owner_cpu == self_cpu ) {
+ giant->nest_level = 0;
+ giant->owner_cpu = NO_OWNER_CPU;
+ _SMP_lock_Release( &giant->lock );
+ }
+}
+
uint32_t _Thread_Dispatch_increment_disable_level( void )
{
ISR_Level isr_level;
--
1.7.7
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