[rtems commit] rtems: Avoid Giant lock in rtems_signal_catch()

[Sebastian Huber]

Module:    rtems
Branch:    master
Commit:    92dee4ab9cf806553d0cdaeb4968d25ced4a8b3a
Changeset: http://git.rtems.org/rtems/commit/?id=92dee4ab9cf806553d0cdaeb4968d25ced4a8b3a

Author:    Sebastian Huber <sebastian.huber at embedded-brains.de>
Date:      Thu Mar 17 06:51:56 2016 +0100

rtems: Avoid Giant lock in rtems_signal_catch()

Update #2555.

---

 cpukit/rtems/include/rtems/rtems/asrimpl.h | 28 ++++++++++++++++++++++------
 cpukit/rtems/src/signalcatch.c             | 11 ++++++-----
 2 files changed, 28 insertions(+), 11 deletions(-)

diff --git a/cpukit/rtems/include/rtems/rtems/asrimpl.h b/cpukit/rtems/include/rtems/rtems/asrimpl.h
index bcfb69a..7c1c648 100644
--- a/cpukit/rtems/include/rtems/rtems/asrimpl.h
+++ b/cpukit/rtems/include/rtems/rtems/asrimpl.h
@@ -59,6 +59,22 @@ RTEMS_INLINE_ROUTINE void _ASR_Destroy( ASR_Information *asr )
   _ISR_lock_Destroy( &asr->Lock );
 }
 
+RTEMS_INLINE_ROUTINE void _ASR_Acquire(
+  ASR_Information  *asr,
+  ISR_lock_Context *lock_context
+)
+{
+  _ISR_lock_ISR_disable_and_acquire( &asr->Lock, lock_context );
+}
+
+RTEMS_INLINE_ROUTINE void _ASR_Release(
+  ASR_Information  *asr,
+  ISR_lock_Context *lock_context
+)
+{
+  _ISR_lock_Release_and_ISR_enable( &asr->Lock, lock_context );
+}
+
 /**
  *  @brief ASR_Swap_signals
  *
@@ -73,11 +89,11 @@ RTEMS_INLINE_ROUTINE void _ASR_Swap_signals (
   rtems_signal_set _signals;
   ISR_lock_Context lock_context;
 
-  _ISR_lock_ISR_disable_and_acquire( &asr->Lock, &lock_context );
+  _ASR_Acquire( asr, &lock_context );
     _signals             = asr->signals_pending;
     asr->signals_pending = asr->signals_posted;
     asr->signals_posted  = _signals;
-  _ISR_lock_Release_and_ISR_enable( &asr->Lock, &lock_context );
+  _ASR_Release( asr, &lock_context );
 }
 
 /**
@@ -122,9 +138,9 @@ RTEMS_INLINE_ROUTINE void _ASR_Post_signals(
 {
   ISR_lock_Context lock_context;
 
-  _ISR_lock_ISR_disable_and_acquire( &asr->Lock, &lock_context );
+  _ASR_Acquire( asr, &lock_context );
     *signal_set |= signals;
-  _ISR_lock_Release_and_ISR_enable( &asr->Lock, &lock_context );
+  _ASR_Release( asr, &lock_context );
 }
 
 RTEMS_INLINE_ROUTINE rtems_signal_set _ASR_Get_posted_signals(
@@ -134,10 +150,10 @@ RTEMS_INLINE_ROUTINE rtems_signal_set _ASR_Get_posted_signals(
   rtems_signal_set signal_set;
   ISR_lock_Context lock_context;
 
-  _ISR_lock_ISR_disable_and_acquire( &asr->Lock, &lock_context );
+  _ASR_Acquire( asr, &lock_context );
     signal_set = asr->signals_posted;
     asr->signals_posted = 0;
-  _ISR_lock_Release_and_ISR_enable( &asr->Lock, &lock_context );
+  _ASR_Release( asr, &lock_context );
 
   return signal_set;
 }
diff --git a/cpukit/rtems/src/signalcatch.c b/cpukit/rtems/src/signalcatch.c
index f0c62f7..7bf298d 100644
--- a/cpukit/rtems/src/signalcatch.c
+++ b/cpukit/rtems/src/signalcatch.c
@@ -72,21 +72,22 @@ rtems_status_code rtems_signal_catch(
   Thread_Control     *executing;
   RTEMS_API_Control  *api;
   ASR_Information    *asr;
+  ISR_lock_Context    lock_context;
 
   executing = _Thread_Get_executing();
   api = (RTEMS_API_Control*)executing->API_Extensions[ THREAD_API_RTEMS ];
   asr = &api->Signal;
 
-  _Thread_Disable_dispatch(); /* cannot reschedule while */
-                              /*   the thread is inconsistent */
+  _ASR_Acquire( asr, &lock_context );
 
   if ( !_ASR_Is_null_handler( asr_handler ) ) {
     asr->mode_set = mode_set;
     asr->handler = asr_handler;
-  }
-  else
+  } else {
     _ASR_Initialize( asr );
-  _Thread_Enable_dispatch();
+  }
+
+  _ASR_Release( asr, &lock_context );
   return RTEMS_SUCCESSFUL;
 }