[PATCH] score: Delete _Thread_BSP_context
Sebastian Huber
sebastian.huber at embedded-brains.de
Thu Feb 13 09:09:49 UTC 2014
Do not return to BSP context in the exit() shutdown path. This makes it
possible to re-use the initialization stack. It can be used for the
interrupt stack for example. On targets with a small RAM this is a
considerable benefit.
This change eliminates also some special cases and simplifies the code.
Disable thread dispatching in rtems_shutdown_executive().
Delete _Thread_Set_global_exit_status(),
_Thread_Get_global_exit_status() and _Thread_Stop_multitasking().
---
cpukit/sapi/src/exinit.c | 10 +---
cpukit/sapi/src/exshutdown.c | 18 +++---
.../score/cpu/arm/armv7m-multitasking-start-stop.c | 36 ++---------
cpukit/score/cpu/arm/rtems/score/cpu.h | 5 +-
cpukit/score/include/rtems/score/threadimpl.h | 65 +-------------------
cpukit/score/src/smp.c | 2 +-
cpukit/score/src/threadstartmultitasking.c | 27 +++------
testsuites/sptests/spsize/size.c | 3 +-
8 files changed, 29 insertions(+), 137 deletions(-)
diff --git a/cpukit/sapi/src/exinit.c b/cpukit/sapi/src/exinit.c
index 10c1559..e8b009b 100644
--- a/cpukit/sapi/src/exinit.c
+++ b/cpukit/sapi/src/exinit.c
@@ -33,7 +33,6 @@
#include <rtems/config.h>
#include <rtems/debug.h>
#include <rtems/extensionimpl.h>
-#include <rtems/fatal.h>
#include <rtems/init.h>
#include <rtems/io.h>
#include <rtems/score/sysstate.h>
@@ -215,25 +214,20 @@ void rtems_initialize_device_drivers(void)
void rtems_initialize_start_multitasking(void)
{
- uint32_t status;
-
_System_state_Set( SYSTEM_STATE_UP );
#if defined(RTEMS_SMP)
_SMP_Request_other_cores_to_perform_first_context_switch();
#endif
- _Thread_Start_multitasking( &_Thread_BSP_context );
+ _Thread_Start_multitasking();
/*******************************************************************
*******************************************************************
*******************************************************************
****** APPLICATION RUNS HERE ******
- ****** RETURNS WHEN SYSTEM IS SHUT DOWN ******
+ ****** THE FUNCTION NEVER RETURNS ******
*******************************************************************
*******************************************************************
*******************************************************************/
-
- status = _Thread_Get_global_exit_status();
- rtems_fatal( RTEMS_FATAL_SOURCE_EXIT, status );
}
diff --git a/cpukit/sapi/src/exshutdown.c b/cpukit/sapi/src/exshutdown.c
index 7a96869..7cf7d35 100644
--- a/cpukit/sapi/src/exshutdown.c
+++ b/cpukit/sapi/src/exshutdown.c
@@ -38,25 +38,25 @@ void rtems_shutdown_executive(
uint32_t result
)
{
+ _Thread_Disable_dispatch();
+
if ( _System_state_Is_up( _System_state_Get() ) ) {
#if defined(RTEMS_SMP)
_SMP_Request_other_cores_to_shutdown();
#endif
- _Thread_Set_global_exit_status( result );
_System_state_Set( SYSTEM_STATE_SHUTDOWN );
- _Thread_Stop_multitasking();
-
- /*******************************************************************
- *******************************************************************
- ****** RETURN TO RTEMS_INITIALIZE_START_MULTITASKING() ******
- ****** AND THEN TO BOOT_CARD() ******
- *******************************************************************
- *******************************************************************/
+ _Internal_error_Occurred( RTEMS_FATAL_SOURCE_EXIT, false, result );
}
_Internal_error_Occurred(
INTERNAL_ERROR_CORE,
true,
INTERNAL_ERROR_SHUTDOWN_WHEN_NOT_UP
);
+
+ /***************************************************************
+ ***************************************************************
+ * SYSTEM SHUTS DOWN!!! WE DO NOT RETURN TO THIS POINT!!! *
+ ***************************************************************
+ ***************************************************************/
}
diff --git a/cpukit/score/cpu/arm/armv7m-multitasking-start-stop.c b/cpukit/score/cpu/arm/armv7m-multitasking-start-stop.c
index f3e96e3..864bb53 100644
--- a/cpukit/score/cpu/arm/armv7m-multitasking-start-stop.c
+++ b/cpukit/score/cpu/arm/armv7m-multitasking-start-stop.c
@@ -1,14 +1,14 @@
/**
* @file
*
- * @brief ARMV7M Start and Stop Multitasking
+ * @brief ARMV7M Start Multitasking
*/
/*
- * Copyright (c) 2011 Sebastian Huber. All rights reserved.
+ * Copyright (c) 2011-2014 Sebastian Huber. All rights reserved.
*
* embedded brains GmbH
- * Obere Lagerstr. 30
+ * Dornierstr. 4
* 82178 Puchheim
* Germany
* <rtems at embedded-brains.de>
@@ -27,18 +27,14 @@
#ifdef ARM_MULTILIB_ARCH_V7M
void __attribute__((naked)) _ARMV7M_Start_multitasking(
- Context_Control *bsp,
Context_Control *heir
)
{
__asm__ volatile (
- /* Store BSP context */
- "stm r0, {r4-r11, lr}\n"
- "str sp, [r0, %[spctxoff]]\n"
/* Restore heir context */
- "ldr r2, [r1, %[spctxoff]]\n"
+ "ldr r2, [r0, %[spctxoff]]\n"
"msr psp, r2\n"
- "ldm r1, {r4-r11, lr}\n"
+ "ldm r0, {r4-r11, lr}\n"
/* Enable process stack pointer (PSP) */
"mrs r2, control\n"
"orr r2, #0x2\n"
@@ -50,26 +46,4 @@ void __attribute__((naked)) _ARMV7M_Start_multitasking(
);
}
-void __attribute__((naked)) _ARMV7M_Stop_multitasking( Context_Control *bsp )
-{
- __asm__ volatile (
- /* Disable interrupts */
- "mov r2, #0x80\n"
- "msr basepri_max, r2\n"
- /* Restore BSP context */
- "ldr r2, [r0, %[spctxoff]]\n"
- "msr msp, r2\n"
- "ldm r0, {r4-r11, lr}\n"
- /* Disable process stack pointer (PSP) */
- "mrs r2, control\n"
- "bic r2, #0x2\n"
- "msr control, r2\n"
- /* Return to BSP */
- "bx lr\n"
- :
- : [spctxoff] "J" (offsetof(Context_Control, register_sp))
- );
- __builtin_unreachable();
-}
-
#endif /* ARM_MULTILIB_ARCH_V7M */
diff --git a/cpukit/score/cpu/arm/rtems/score/cpu.h b/cpukit/score/cpu/arm/rtems/score/cpu.h
index b423dba..f56f9a6 100644
--- a/cpukit/score/cpu/arm/rtems/score/cpu.h
+++ b/cpukit/score/cpu/arm/rtems/score/cpu.h
@@ -458,11 +458,8 @@ void _CPU_Context_restore( Context_Control *new_context )
RTEMS_COMPILER_NO_RETURN_ATTRIBUTE;
#if defined(ARM_MULTILIB_ARCH_V7M)
- void _ARMV7M_Start_multitasking( Context_Control *bsp, Context_Control *heir );
- void _ARMV7M_Stop_multitasking( Context_Control *bsp )
- RTEMS_COMPILER_NO_RETURN_ATTRIBUTE;
+ void _ARMV7M_Start_multitasking( Context_Control *heir );
#define _CPU_Start_multitasking _ARMV7M_Start_multitasking
- #define _CPU_Stop_multitasking _ARMV7M_Stop_multitasking
#endif
void _CPU_Context_volatile_clobber( uintptr_t pattern );
diff --git a/cpukit/score/include/rtems/score/threadimpl.h b/cpukit/score/include/rtems/score/threadimpl.h
index 4f4fbc7..7c1d2a7 100644
--- a/cpukit/score/include/rtems/score/threadimpl.h
+++ b/cpukit/score/include/rtems/score/threadimpl.h
@@ -20,6 +20,7 @@
#define _RTEMS_SCORE_THREADIMPL_H
#include <rtems/score/thread.h>
+#include <rtems/score/interr.h>
#include <rtems/score/isr.h>
#include <rtems/score/objectimpl.h>
#include <rtems/score/statesimpl.h>
@@ -54,15 +55,6 @@ SCORE_EXTERN void *rtems_ada_self;
SCORE_EXTERN Objects_Information _Thread_Internal_information;
/**
- * The following context area contains the context of the "thread"
- * which invoked the start multitasking routine. This context is
- * restored as the last action of the stop multitasking routine. Thus
- * control of the processor can be returned to the environment
- * which initiated the system.
- */
-SCORE_EXTERN Context_Control _Thread_BSP_context;
-
-/**
* The following holds how many user extensions are in the system. This
* is used to determine how many user extension data areas to allocate
* per thread.
@@ -114,13 +106,8 @@ void _Thread_Create_idle(void);
* This routine initiates multitasking. It is invoked only as
* part of initialization and its invocation is the last act of
* the non-multitasking part of the system initialization.
- *
- *
- * - INTERRUPT LATENCY:
- * + ready chain
- * + select heir
*/
-void _Thread_Start_multitasking( Context_Control *context );
+void _Thread_Start_multitasking( void ) RTEMS_COMPILER_NO_RETURN_ATTRIBUTE;
/**
* @brief Allocate the requested stack space for the thread.
@@ -446,36 +433,6 @@ void _Thread_blocking_operation_Cancel(
);
/**
- * This routine halts multitasking and returns control to
- * the "thread" (i.e. the BSP) which initially invoked the
- * routine which initialized the system.
- */
-
-RTEMS_INLINE_ROUTINE void _Thread_Stop_multitasking( void )
-{
-#if defined(_CPU_Stop_multitasking)
- _CPU_Stop_multitasking( &_Thread_BSP_context );
-#else
- /*
- * This may look a bit of an odd but _Context_Restart_self is just
- * a very careful restore of a specific context which ensures that
- * if we were running within the same context, it would work.
- *
- * And we will not return to this thread, so there is no point of
- * saving the context.
- */
- _Context_Restart_self( &_Thread_BSP_context );
-#endif
-
- /***************************************************************
- ***************************************************************
- * SYSTEM SHUTS DOWN!!! WE DO NOT RETURN TO THIS POINT!!! *
- ***************************************************************
- ***************************************************************
- */
-}
-
-/**
* This function returns true if the_thread is the currently executing
* thread, and false otherwise.
*/
@@ -630,24 +587,6 @@ RTEMS_INLINE_ROUTINE void _Thread_Internal_free (
_Objects_Free( &_Thread_Internal_information, &the_task->Object );
}
-RTEMS_INLINE_ROUTINE void _Thread_Set_global_exit_status(
- uint32_t exit_status
-)
-{
- Thread_Control *idle = (Thread_Control *)
- _Thread_Internal_information.local_table[ 1 ];
-
- idle->Wait.return_code = exit_status;
-}
-
-RTEMS_INLINE_ROUTINE uint32_t _Thread_Get_global_exit_status( void )
-{
- const Thread_Control *idle = (const Thread_Control *)
- _Thread_Internal_information.local_table[ 1 ];
-
- return idle->Wait.return_code;
-}
-
RTEMS_INLINE_ROUTINE void _Thread_Signal_notification( Thread_Control *thread )
{
if ( _ISR_Is_in_progress() && _Thread_Is_executing( thread ) ) {
diff --git a/cpukit/score/src/smp.c b/cpukit/score/src/smp.c
index 2f8a488..df1c6d3 100644
--- a/cpukit/score/src/smp.c
+++ b/cpukit/score/src/smp.c
@@ -40,7 +40,7 @@ void rtems_smp_secondary_cpu_initialize( void )
_Per_CPU_Wait_for_state( self_cpu, PER_CPU_STATE_BEGIN_MULTITASKING );
- _Thread_Start_multitasking( NULL );
+ _Thread_Start_multitasking();
}
void rtems_smp_process_interrupt( void )
diff --git a/cpukit/score/src/threadstartmultitasking.c b/cpukit/score/src/threadstartmultitasking.c
index 52337ab..a676364 100644
--- a/cpukit/score/src/threadstartmultitasking.c
+++ b/cpukit/score/src/threadstartmultitasking.c
@@ -20,7 +20,7 @@
#include <rtems/score/threadimpl.h>
-void _Thread_Start_multitasking( Context_Control *context )
+void _Thread_Start_multitasking( void )
{
Per_CPU_Control *self_cpu = _Per_CPU_Get();
Thread_Control *heir = self_cpu->heir;
@@ -28,7 +28,13 @@ void _Thread_Start_multitasking( Context_Control *context )
#if defined(RTEMS_SMP)
_Per_CPU_Change_state( self_cpu, PER_CPU_STATE_UP );
+ /*
+ * Threads begin execution in the _Thread_Handler() function. This
+ * function will set the thread dispatch disable level to zero and calls
+ * _Per_CPU_Release().
+ */
_Per_CPU_Acquire( self_cpu );
+ self_cpu->thread_dispatch_disable_level = 1;
self_cpu->executing->is_executing = false;
heir->is_executing = true;
@@ -59,26 +65,9 @@ void _Thread_Start_multitasking( Context_Control *context )
_Context_Restore_fp( &heir->fp_context );
#endif
-#if defined(RTEMS_SMP)
- if ( context != NULL ) {
-#endif
-
#if defined(_CPU_Start_multitasking)
- _CPU_Start_multitasking( context, &heir->Registers );
+ _CPU_Start_multitasking( &heir->Registers );
#else
- _Context_Switch( context, &heir->Registers );
-#endif
-
-#if defined(RTEMS_SMP)
- } else {
- /*
- * Threads begin execution in the _Thread_Handler() function. This
- * function will set the thread dispatch disable level to zero and calls
- * _Per_CPU_Release().
- */
- self_cpu->thread_dispatch_disable_level = 1;
-
_CPU_Context_restore( &heir->Registers );
- }
#endif
}
diff --git a/testsuites/sptests/spsize/size.c b/testsuites/sptests/spsize/size.c
index f204c05..5b3cefe 100644
--- a/testsuites/sptests/spsize/size.c
+++ b/testsuites/sptests/spsize/size.c
@@ -385,8 +385,7 @@ uninitialized =
/*tasksimpl.h*/ (sizeof _RTEMS_tasks_Information) +
-/*thread.h*/ (sizeof _Thread_BSP_context) +
- (sizeof _Thread_Dispatch_disable_level) +
+/*thread.h*/ (sizeof _Thread_Dispatch_disable_level) +
(sizeof _Thread_Maximum_extensions) +
(sizeof _Thread_Ticks_per_timeslice) +
(sizeof _Thread_Executing) +
--
1.7.7
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