score: Remove the Giant lock

Update #2555.

7 files changed, 0 insertions, 427 deletions

diff --git a/cpukit/score/Makefile.am b/cpukit/score/Makefile.am
index 0fe78dad00..7ca63417db 100644
--- a/cpukit/score/Makefile.am
+++ b/cpukit/score/Makefile.am
@@ -299,7 +299,6 @@ libscore_a_SOURCES += src/rbtreereplace.c
 libscore_a_SOURCES += src/thread.c src/threadchangepriority.c \
     src/threadclearstate.c src/threadcreateidle.c \
     src/threaddispatch.c \
-    src/threadenabledispatch.c src/threaddisabledispatch.c \
     src/threadget.c src/threadhandler.c src/threadinitialize.c \
     src/threadloadenv.c \
     src/threadrestart.c src/threadsetpriority.c \
@@ -315,10 +314,6 @@ libscore_a_SOURCES += src/threadtimeout.c
 libscore_a_SOURCES += src/threadwaitgetid.c
 libscore_a_SOURCES += src/threadyield.c
 
-if HAS_SMP
-libscore_a_SOURCES += src/threaddispatchdisablelevel.c
-endif
-
 ## THREADQ_C_FILES
 libscore_a_SOURCES += src/threadq.c \
     src/threadqenqueue.c \
diff --git a/cpukit/score/include/rtems/score/percpu.h b/cpukit/score/include/rtems/score/percpu.h
index ea69cd6c2b..55f799ed1c 100644
--- a/cpukit/score/include/rtems/score/percpu.h
+++ b/cpukit/score/include/rtems/score/percpu.h
@@ -393,12 +393,6 @@ typedef struct Per_CPU_Control {
     #endif
 
     /**
-     * @brief Context for the Giant lock acquire and release pair of this
-     * processor.
-     */
-    SMP_lock_Context Giant_lock_context;
-
-    /**
      * @brief Bit field for SMP messages.
      *
      * This bit field is not protected locks.  Atomic operations are used to
diff --git a/cpukit/score/include/rtems/score/threaddispatch.h b/cpukit/score/include/rtems/score/threaddispatch.h
index be3883ffbc..573d1be2b3 100644
--- a/cpukit/score/include/rtems/score/threaddispatch.h
+++ b/cpukit/score/include/rtems/score/threaddispatch.h
@@ -86,122 +86,6 @@ RTEMS_INLINE_ROUTINE void _Thread_Dispatch_initialization( void )
   _Thread_Dispatch_disable_level = 1;
 }
 
-#if defined(RTEMS_SMP)
-  /**
-   * @brief Acquires the giant lock.
-   *
-   * The giant lock is a recursive SMP lock protecting nearly all operating
-   * system services.
-   *
-   * This lock is implicitly acquired in
-   * _Thread_Dispatch_increment_disable_level().
-   *
-   * Thread dispatching must be disabled before the Giant lock can be acquired
-   * and must no be enabled while owning the Giant lock.  The thread dispatch
-   * disable level is not altered by this function.
-   *
-   * @param[in] cpu_self The current processor.
-   */
-  void _Giant_Acquire( Per_CPU_Control *cpu_self );
-
-  /**
-   * @brief Releases the giant lock.
-   *
-   * This lock is implicitly released in
-   * _Thread_Dispatch_decrement_disable_level().
-   *
-   * The thread dispatch disable level is not altered by this function.
-   *
-   * @param[in] cpu_self The current processor.
-   */
-  void _Giant_Release( Per_CPU_Control *cpu_self );
-
-  /**
-   * @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_shutdown().
-   *
-   * @param[in] cpu_self The current processor.
-   */
-  void _Giant_Drop( Per_CPU_Control *cpu_self );
-
-  /**
-   *  @brief Increments the thread dispatch level.
-   *
-   * This rountine increments the thread dispatch level
-   */
-  uint32_t _Thread_Dispatch_increment_disable_level(void);
-
-  /**
-   *  @brief Decrements the thread dispatch level.
-   *
-   * This routine decrements the thread dispatch level.
-   */
-  uint32_t _Thread_Dispatch_decrement_disable_level(void);
-#else /* RTEMS_SMP */
-  /**
-   * @brief Increase thread dispatch disable level.
-   *
-   * This rountine increments the thread dispatch level
-   */
-  RTEMS_INLINE_ROUTINE uint32_t _Thread_Dispatch_increment_disable_level(void)
-  {
-    uint32_t disable_level = _Thread_Dispatch_disable_level;
-#if defined( RTEMS_PROFILING )
-    ISR_Level level;
-
-    _ISR_Local_disable( level );
-    _Profiling_Thread_dispatch_disable( _Per_CPU_Get(), disable_level );
-#endif
-
-    ++disable_level;
-    _Thread_Dispatch_disable_level = disable_level;
-
-#if defined( RTEMS_PROFILING )
-    _ISR_Local_enable( level );
-#endif
-
-    return disable_level;
-  }
-
-  /**
-   * @brief Decrease thread dispatch disable level.
-   *
-   * This routine decrements the thread dispatch level.
-   */
-  RTEMS_INLINE_ROUTINE uint32_t _Thread_Dispatch_decrement_disable_level(void)
-  {
-    uint32_t disable_level = _Thread_Dispatch_disable_level;
-#if defined( RTEMS_PROFILING )
-    ISR_Level level;
-
-    _ISR_Local_disable( level );
-#endif
-
-    --disable_level;
-    _Thread_Dispatch_disable_level = disable_level;
-
-#if defined( RTEMS_PROFILING )
-    _Profiling_Thread_dispatch_enable( _Per_CPU_Get(), disable_level );
-    _ISR_Local_enable( level );
-#endif
-
-    return disable_level;
-  }
-
-  RTEMS_INLINE_ROUTINE void _Giant_Acquire( Per_CPU_Control *cpu_self )
-  {
-    (void) cpu_self;
-  }
-
-  RTEMS_INLINE_ROUTINE void _Giant_Release( Per_CPU_Control *cpu_self )
-  {
-    (void) cpu_self;
-  }
-#endif /* RTEMS_SMP */
-
 /**
  * @brief Performs a thread dispatch if necessary.
  *
@@ -240,8 +124,6 @@ void _Thread_Do_dispatch( Per_CPU_Control *cpu_self, ISR_Level level );
  * @brief Disables thread dispatching inside a critical section (interrupts
  * disabled) with the current processor.
  *
- * This function does not acquire the Giant lock.
- *
  * @param[in] cpu_self The current processor.
  * @param[in] lock_context The lock context of the corresponding
  * _ISR_lock_ISR_disable() that started the critical section.
@@ -270,8 +152,6 @@ RTEMS_INLINE_ROUTINE Per_CPU_Control *_Thread_Dispatch_disable_with_CPU(
  * @brief Disables thread dispatching inside a critical section (interrupts
  * disabled).
  *
- * This function does not acquire the Giant lock.
- *
  * @param[in] lock_context The lock context of the corresponding
  * _ISR_lock_ISR_disable() that started the critical section.
  *
@@ -287,8 +167,6 @@ RTEMS_INLINE_ROUTINE Per_CPU_Control *_Thread_Dispatch_disable_critical(
 /**
  * @brief Disables thread dispatching.
  *
- * This function does not acquire the Giant lock.
- *
  * @return The current processor.
  */
 RTEMS_INLINE_ROUTINE Per_CPU_Control *_Thread_Dispatch_disable( void )
@@ -314,8 +192,6 @@ RTEMS_INLINE_ROUTINE Per_CPU_Control *_Thread_Dispatch_disable( void )
  *
  * May perfrom a thread dispatch if necessary as a side-effect.
  *
- * This function does not release the Giant lock.
- *
  * @param[in] cpu_self The current processor.
  */
 RTEMS_INLINE_ROUTINE void _Thread_Dispatch_enable( Per_CPU_Control *cpu_self )
@@ -343,8 +219,6 @@ RTEMS_INLINE_ROUTINE void _Thread_Dispatch_enable( Per_CPU_Control *cpu_self )
 /**
  * @brief Unnests thread dispatching.
  *
- * This function does not release the Giant lock.
- *
  * @param[in] cpu_self The current processor.
  */
 RTEMS_INLINE_ROUTINE void _Thread_Dispatch_unnest( Per_CPU_Control *cpu_self )
@@ -352,55 +226,6 @@ RTEMS_INLINE_ROUTINE void _Thread_Dispatch_unnest( Per_CPU_Control *cpu_self )
   --cpu_self->thread_dispatch_disable_level;
 }
 
-/**
- * @brief Disables thread dispatching and acquires the Giant lock.
- */
-#if defined ( __THREAD_DO_NOT_INLINE_DISABLE_DISPATCH__ )
-void _Thread_Disable_dispatch( void );
-#else
-RTEMS_INLINE_ROUTINE void _Thread_Disable_dispatch( void )
-{
-  _Thread_Dispatch_increment_disable_level();
-  RTEMS_COMPILER_MEMORY_BARRIER();
-}
-#endif
-
-RTEMS_INLINE_ROUTINE void _Thread_Enable_dispatch_body( void )
-{
-  Per_CPU_Control *cpu_self = _Per_CPU_Get();
-
-  _Giant_Release( cpu_self );
-  _Thread_Dispatch_enable( cpu_self );
-}
-
-/**
- * @brief Enables thread dispatching and releases the Giant lock.
- *
- * May perfrom a thread dispatch if necessary as a side-effect.
- */
-#if defined ( __THREAD_DO_NOT_INLINE_ENABLE_DISPATCH__ )
-  void _Thread_Enable_dispatch( void );
-#else
-  /* inlining of enable dispatching must be true */
-  RTEMS_INLINE_ROUTINE void _Thread_Enable_dispatch( void )
-  {
-    RTEMS_COMPILER_MEMORY_BARRIER();
-    _Thread_Enable_dispatch_body();
-  }
-#endif
-
-/**
- * @brief Enables thread dispatching and releases the Giant lock.
- *
- * @warning A thread dispatch is not performed as a side-effect.  Use this
- * function with
- */
-RTEMS_INLINE_ROUTINE void _Thread_Unnest_dispatch( void )
-{
-  RTEMS_COMPILER_MEMORY_BARRIER();
-  _Thread_Dispatch_decrement_disable_level();
-}
-
 /** @} */
 
 #ifdef __cplusplus
diff --git a/cpukit/score/src/smp.c b/cpukit/score/src/smp.c
index 85256b044c..e26de42e68 100644
--- a/cpukit/score/src/smp.c
+++ b/cpukit/score/src/smp.c
@@ -21,7 +21,6 @@
 #include <rtems/score/smpimpl.h>
 #include <rtems/score/assert.h>
 #include <rtems/score/schedulerimpl.h>
-#include <rtems/score/threaddispatch.h>
 #include <rtems/score/threadimpl.h>
 #include <rtems/config.h>
 
@@ -162,14 +161,6 @@ void _SMP_Request_shutdown( void )
   Per_CPU_Control *self_cpu = _Per_CPU_Get();
 
   _Per_CPU_State_change( self_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_cpu );
 }
 
 void _SMP_Send_message( uint32_t cpu_index, unsigned long message )
diff --git a/cpukit/score/src/threaddisabledispatch.c b/cpukit/score/src/threaddisabledispatch.c
deleted file mode 100644
index 8746cd07f6..0000000000
--- a/cpukit/score/src/threaddisabledispatch.c
+++ /dev/null
@@ -1,60 +0,0 @@
-/**
- * @file
- *
- * @brief Disaable Thread Dispatching
- * @ingroup ScoreThread
- */
-
-/*
- *
- *
- *  COPYRIGHT (c) 1989-2011.
- *  On-Line Applications Research Corporation (OAR).
- *
- *  The license and distribution terms for this file may be
- *  found in the file LICENSE in this distribution or at
- *  http://www.rtems.org/license/LICENSE.
- */
-
-#if HAVE_CONFIG_H
-#include "config.h"
-#endif
-
-#include <rtems/system.h>
-#include <rtems/score/sysstate.h>
-#include <rtems/score/thread.h>
-#include <rtems/score/threaddispatch.h>
-
-#if defined ( __THREAD_DO_NOT_INLINE_DISABLE_DISPATCH__ )
-void _Thread_Disable_dispatch( void )
-{
-  /*
-   *  This check is very brutal to system performance but is very helpful
-   *  at finding blown stack problems.  If you have a stack problem and
-   *  need help finding it, then uncomment this code.  Every system
-   *  call will check the stack and since mutexes are used frequently
-   *  in most systems, you might get lucky.
-   */
-  #if defined(RTEMS_HEAVY_STACK_DEBUG)
-    if (_System_state_Is_up(_System_state_Get()) && (_ISR_Nest_level == 0)) {
-      if ( rtems_stack_checker_is_blown() ) {
-	printk( "Stack blown!!\n" );
-	rtems_fatal_error_occurred( 99 );
-      }
-    }
-  #endif
-
-  _Thread_Dispatch_increment_disable_level();
-  RTEMS_COMPILER_MEMORY_BARRIER();
-
-  /*
-   * This check is even more brutal than the other one.  This enables
-   * malloc heap integrity checking upon entry to every system call.
-   */
-  #if defined(RTEMS_HEAVY_MALLOC_DEBUG)
-    if ( _Thread_Dispatch_get_disable_level() == 1 ) {
-      _Heap_Walk( RTEMS_Malloc_Heap,99, false );
-    }
-  #endif
-}
-#endif
diff --git a/cpukit/score/src/threaddispatchdisablelevel.c b/cpukit/score/src/threaddispatchdisablelevel.c
deleted file mode 100644
index 75b12bd358..0000000000
--- a/cpukit/score/src/threaddispatchdisablelevel.c
+++ /dev/null
@@ -1,140 +0,0 @@
-/**
- * @file
- *
- * @brief Thread Dispatch Disable Functions
- *
- * @ingroup ScoreThread
- */
-
-/*
- *  COPYRIGHT (c) 1989-2011.
- *  On-Line Applications Research Corporation (OAR).
- *
- *  The license and distribution terms for this file may be
- *  found in the file LICENSE in this distribution or at
- *  http://www.rtems.org/license/LICENSE.
- */
-
-#include <rtems/score/threaddispatch.h>
-#include <rtems/score/assert.h>
-#include <rtems/score/profiling.h>
-#include <rtems/score/sysstate.h>
-
-#define NO_OWNER_CPU NULL
-
-typedef struct {
-  SMP_lock_Control lock;
-  Per_CPU_Control *owner_cpu;
-  uint32_t nest_level;
-} Giant_Control;
-
-static Giant_Control _Giant = {
-  .lock = SMP_LOCK_INITIALIZER("Giant"),
-  .owner_cpu = NO_OWNER_CPU,
-  .nest_level = 0
-};
-
-static void _Giant_Do_acquire( Per_CPU_Control *cpu_self )
-{
-  Giant_Control *giant = &_Giant;
-
-  if ( giant->owner_cpu != cpu_self ) {
-    _SMP_lock_Acquire( &giant->lock, &cpu_self->Giant_lock_context );
-    giant->owner_cpu = cpu_self;
-    giant->nest_level = 1;
-  } else {
-    ++giant->nest_level;
-  }
-}
-
-static void _Giant_Do_release( Per_CPU_Control *cpu_self )
-{
-  Giant_Control *giant = &_Giant;
-
-  --giant->nest_level;
-  if ( giant->nest_level == 0 ) {
-    giant->owner_cpu = NO_OWNER_CPU;
-    _SMP_lock_Release( &giant->lock, &cpu_self->Giant_lock_context );
-  }
-}
-
-void _Giant_Drop( Per_CPU_Control *cpu_self )
-{
-  Giant_Control *giant = &_Giant;
-
-  _Assert( _ISR_Get_level() != 0 );
-
-  if ( giant->owner_cpu == cpu_self ) {
-    giant->nest_level = 0;
-    giant->owner_cpu = NO_OWNER_CPU;
-    _SMP_lock_Release( &giant->lock, &cpu_self->Giant_lock_context );
-  }
-}
-
-uint32_t _Thread_Dispatch_increment_disable_level( void )
-{
-  ISR_Level isr_level;
-  uint32_t disable_level;
-  Per_CPU_Control *cpu_self;
-
-  _ISR_Local_disable( isr_level );
-
-  /*
-   * We must obtain the processor after interrupts are disabled to prevent
-   * thread migration.
-   */
-  cpu_self = _Per_CPU_Get();
-
-  _Giant_Do_acquire( cpu_self );
-
-  disable_level = cpu_self->thread_dispatch_disable_level;
-  _Profiling_Thread_dispatch_disable( cpu_self, disable_level );
-  ++disable_level;
-  cpu_self->thread_dispatch_disable_level = disable_level;
-
-  _ISR_Local_enable( isr_level );
-
-  return disable_level;
-}
-
-uint32_t _Thread_Dispatch_decrement_disable_level( void )
-{
-  ISR_Level isr_level;
-  uint32_t disable_level;
-  Per_CPU_Control *cpu_self;
-
-  _ISR_Local_disable( isr_level );
-
-  cpu_self = _Per_CPU_Get();
-  disable_level = cpu_self->thread_dispatch_disable_level;
-  _Assert( disable_level > 0);
-  --disable_level;
-  cpu_self->thread_dispatch_disable_level = disable_level;
-
-  _Giant_Do_release( cpu_self );
-
-  _Profiling_Thread_dispatch_enable( cpu_self, disable_level );
-  _ISR_Local_enable( isr_level );
-
-  return disable_level;
-}
-
-void _Giant_Acquire( Per_CPU_Control *cpu_self )
-{
-  ISR_Level isr_level;
-
-  _ISR_Local_disable( isr_level );
-  _Assert( _Thread_Dispatch_disable_level != 0 );
-  _Giant_Do_acquire( cpu_self );
-  _ISR_Local_enable( isr_level );
-}
-
-void _Giant_Release( Per_CPU_Control *cpu_self )
-{
-  ISR_Level isr_level;
-
-  _ISR_Local_disable( isr_level );
-  _Assert( _Thread_Dispatch_disable_level != 0 );
-  _Giant_Do_release( cpu_self );
-  _ISR_Local_enable( isr_level );
-}
diff --git a/cpukit/score/src/threadenabledispatch.c b/cpukit/score/src/threadenabledispatch.c
deleted file mode 100644
index baf58a06d2..0000000000
--- a/cpukit/score/src/threadenabledispatch.c
+++ /dev/null
@@ -1,32 +0,0 @@
-/**
- * @file
- *
- * @brief Enable Dispatching of Threads
- *
- * @ingroup ScoreThread
- */
-
-/*
- *   _Thread_Enable_dispatch
- *
- *
- *  COPYRIGHT (c) 1989-2011.
- *  On-Line Applications Research Corporation (OAR).
- *
- *  The license and distribution terms for this file may be
- *  found in the file LICENSE in this distribution or at
- *  http://www.rtems.org/license/LICENSE.
- */
-
-#if HAVE_CONFIG_H
-#include "config.h"
-#endif
-
-#include <rtems/score/threaddispatch.h>
-
-#if defined (__THREAD_DO_NOT_INLINE_ENABLE_DISPATCH__ )
-void _Thread_Enable_dispatch( void )
-{
-  _Thread_Enable_dispatch_body();
-}
-#endif