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/**
* @file
*
* @brief Thread Handler
* @ingroup ScoreThread
*/
/*
* COPYRIGHT (c) 1989-2012.
* 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.com/license/LICENSE.
*/
#if HAVE_CONFIG_H
#include "config.h"
#endif
#include <rtems/score/threadimpl.h>
#include <rtems/score/assert.h>
#include <rtems/score/interr.h>
#include <rtems/score/isrlevel.h>
#include <rtems/score/userextimpl.h>
/*
* Conditional magic to determine what style of C++ constructor
* initialization this target and compiler version uses.
*/
#if defined(__USE_INIT_FINI__)
#if defined(__M32R__)
#define INIT_NAME __init
#elif defined(__ARM_EABI__)
#define INIT_NAME __libc_init_array
#else
#define INIT_NAME _init
#endif
extern void INIT_NAME(void);
#define EXECUTE_GLOBAL_CONSTRUCTORS
#endif
#if defined(__USE__MAIN__)
extern void __main(void);
#define INIT_NAME __main
#define EXECUTE_GLOBAL_CONSTRUCTORS
#endif
#if defined(EXECUTE_GLOBAL_CONSTRUCTORS)
static bool _Thread_Handler_is_constructor_execution_required(
Thread_Control *executing
)
{
static bool doneConstructors;
bool doCons = false;
#if defined(RTEMS_SMP)
static SMP_lock_Control constructor_lock = SMP_LOCK_INITIALIZER;
if ( !doneConstructors ) {
_SMP_lock_Acquire( &constructor_lock );
#endif
#if defined(RTEMS_MULTIPROCESSING)
doCons = !doneConstructors
&& _Objects_Get_API( executing->Object.id ) != OBJECTS_INTERNAL_API;
if (doCons)
doneConstructors = true;
#else
(void) executing;
doCons = !doneConstructors;
doneConstructors = true;
#endif
#if defined(RTEMS_SMP)
_SMP_lock_Release( &constructor_lock );
}
#endif
return doCons;
}
#endif
void _Thread_Handler( void )
{
ISR_Level level;
Thread_Control *executing;
#if defined(EXECUTE_GLOBAL_CONSTRUCTORS)
bool doCons;
#endif
executing = _Thread_Executing;
/*
* Some CPUs need to tinker with the call frame or registers when the
* thread actually begins to execute for the first time. This is a
* hook point where the port gets a shot at doing whatever it requires.
*/
_Context_Initialization_at_thread_begin();
#if !defined(RTEMS_SMP)
/*
* have to put level into a register for those cpu's that use
* inline asm here
*/
level = executing->Start.isr_level;
_ISR_Set_level( level );
#endif
#if defined(EXECUTE_GLOBAL_CONSTRUCTORS)
doCons = _Thread_Handler_is_constructor_execution_required( executing );
#endif
/*
* Initialize the floating point context because we do not come
* through _Thread_Dispatch on our first invocation. So the normal
* code path for performing the FP context switch is not hit.
*/
#if ( CPU_HARDWARE_FP == TRUE ) || ( CPU_SOFTWARE_FP == TRUE )
#if ( CPU_USE_DEFERRED_FP_SWITCH == TRUE )
if ( (executing->fp_context != NULL) &&
!_Thread_Is_allocated_fp( executing ) ) {
if ( _Thread_Allocated_fp != NULL )
_Context_Save_fp( &_Thread_Allocated_fp->fp_context );
_Thread_Allocated_fp = executing;
}
#endif
#endif
/*
* Take care that 'begin' extensions get to complete before
* 'switch' extensions can run. This means must keep dispatch
* disabled until all 'begin' extensions complete.
*/
_User_extensions_Thread_begin( executing );
/*
* At this point, the dispatch disable level BETTER be 1.
*/
#if defined(RTEMS_SMP)
{
/*
* On SMP we enter _Thread_Handler() with interrupts disabled and
* _Thread_Dispatch() obtained the per-CPU lock for us. We have to
* release it here and set the desired interrupt level of the thread.
*/
Per_CPU_Control *per_cpu = _Per_CPU_Get();
_Assert( per_cpu->thread_dispatch_disable_level == 1 );
_Assert( _ISR_Get_level() != 0 );
per_cpu->thread_dispatch_disable_level = 0;
_Per_CPU_Release( per_cpu );
level = executing->Start.isr_level;
_ISR_Set_level( level);
/*
* The thread dispatch level changed from one to zero. Make sure we lose
* no thread dispatch necessary update.
*/
_Thread_Dispatch();
}
#else
_Thread_Enable_dispatch();
#endif
#if defined(EXECUTE_GLOBAL_CONSTRUCTORS)
/*
* _init could be a weak symbol and we SHOULD test it but it isn't
* in any configuration I know of and it generates a warning on every
* RTEMS target configuration. --joel (12 May 2007)
*/
if (doCons) /* && (volatile void *)_init) */ {
INIT_NAME ();
}
#endif
/*
* RTEMS supports multiple APIs and each API can define a different
* thread/task prototype. The following code supports invoking the
* user thread entry point using the prototype expected.
*/
if ( executing->Start.prototype == THREAD_START_NUMERIC ) {
executing->Wait.return_argument =
(*(Thread_Entry_numeric) executing->Start.entry_point)(
executing->Start.numeric_argument
);
}
#if defined(RTEMS_POSIX_API)
else if ( executing->Start.prototype == THREAD_START_POINTER ) {
executing->Wait.return_argument =
(*(Thread_Entry_pointer) executing->Start.entry_point)(
executing->Start.pointer_argument
);
}
#endif
#if defined(FUNCTIONALITY_NOT_CURRENTLY_USED_BY_ANY_API)
else if ( executing->Start.prototype == THREAD_START_BOTH_POINTER_FIRST ) {
executing->Wait.return_argument =
(*(Thread_Entry_both_pointer_first) executing->Start.entry_point)(
executing->Start.pointer_argument,
executing->Start.numeric_argument
);
}
else if ( executing->Start.prototype == THREAD_START_BOTH_NUMERIC_FIRST ) {
executing->Wait.return_argument =
(*(Thread_Entry_both_numeric_first) executing->Start.entry_point)(
executing->Start.numeric_argument,
executing->Start.pointer_argument
);
}
#endif
/*
* In the switch above, the return code from the user thread body
* was placed in return_argument. This assumed that if it returned
* anything (which is not supporting in all APIs), then it would be
* able to fit in a (void *).
*/
_User_extensions_Thread_exitted( executing );
_Internal_error_Occurred(
INTERNAL_ERROR_CORE,
true,
INTERNAL_ERROR_THREAD_EXITTED
);
}
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