static void _Scheduler_default_Tick_for_executing(
Scheduler_Control *scheduler,
Thread_Control *executing
)
{
#ifdef __RTEMS_USE_TICKS_FOR_STATISTICS__
/*
* Increment the number of ticks this thread has been executing
*/
executing->cpu_time_used++;
#endif
/*
* If the thread is not preemptible or is not ready, then
* just return.
*/
if ( !executing->is_preemptible )
return;
if ( !_States_Is_ready( executing->current_state ) )
return;
/*
* The cpu budget algorithm determines what happens next.
*/
switch ( executing->budget_algorithm ) {
case THREAD_CPU_BUDGET_ALGORITHM_NONE:
break;
case THREAD_CPU_BUDGET_ALGORITHM_RESET_TIMESLICE:
#if defined(RTEMS_SCORE_THREAD_ENABLE_EXHAUST_TIMESLICE)
case THREAD_CPU_BUDGET_ALGORITHM_EXHAUST_TIMESLICE:
#endif
if ( (int)(--executing->cpu_time_budget) <= 0 ) {
/*
* A yield performs the ready chain mechanics needed when
* resetting a timeslice. If no other thread's are ready
* at the priority of the currently executing thread, then the
* executing thread's timeslice is reset. Otherwise, the
* currently executing thread is placed at the rear of the
* FIFO for this priority and a new heir is selected.
*/
_Scheduler_Yield( scheduler, executing );
executing->cpu_time_budget =
rtems_configuration_get_ticks_per_timeslice();
}
break;
#if defined(RTEMS_SCORE_THREAD_ENABLE_SCHEDULER_CALLOUT)
case THREAD_CPU_BUDGET_ALGORITHM_CALLOUT:
if ( --executing->cpu_time_budget == 0 )
(*executing->budget_callout)( executing );
break;
#endif
}
}
/* Clock_exit --
* This shuts down the timer if it was enabled and removes it
* from the MCF5206E interrupt mask.
*
* PARAMETERS:
* none
*
* RETURNS:
* none
*/
void
Clock_exit(void)
{
if (rtems_configuration_get_ticks_per_timeslice()) {
uint32_t icr;
/* disable all timer1 interrupts */
icr = g_intctrl_regs->icr1;
icr = icr & ~(MCF5272_ICR1_TMR1_MASK | MCF5272_ICR1_TMR1_PI);
icr |= (MCF5272_ICR1_TMR1_IPL(0) | MCF5272_ICR1_TMR1_PI);
g_intctrl_regs->icr1 = icr;
/* reset timer1 */
g_timer_regs->tmr1 = MCF5272_TMR_CLK_STOP;
/* clear pending */
g_timer_regs->ter1 = MCF5272_TER_REF | MCF5272_TER_CAP;
}
}
/* Install_clock --
* This initialises timer1 with the BSP timeslice config value
* as a reference and sets up the interrupt handler for clock ticks.
*
* PARAMETERS:
* clock_isr - clock interrupt handler routine
*
* RETURNS:
* none.
*/
static void
Install_clock(rtems_isr_entry clock_isr)
{
uint32_t icr;
Clock_driver_ticks = 0;
if (rtems_configuration_get_ticks_per_timeslice()) {
/* Register the interrupt handler */
set_vector(clock_isr, BSP_INTVEC_TMR1, 1);
/* Reset timer 1 */
g_timer_regs->tmr1 = MCF5272_TMR_RST;
g_timer_regs->tmr1 = MCF5272_TMR_CLK_STOP;
g_timer_regs->tmr1 = MCF5272_TMR_RST;
g_timer_regs->tcn1 = 0; /* reset counter */
g_timer_regs->ter1 = MCF5272_TER_REF | MCF5272_TER_CAP;
/* Set Timer 1 prescaler so that it counts in microseconds */
g_timer_regs->tmr1 = (
((((BSP_SYSTEM_FREQUENCY / 1000000) - 1) << MCF5272_TMR_PS_SHIFT) |
MCF5272_TMR_CE_DISABLE |
MCF5272_TMR_ORI |
MCF5272_TMR_FRR |
MCF5272_TMR_CLK_MSTR |
MCF5272_TMR_RST));
/* Set the timer timeout value from the BSP config */
g_timer_regs->trr1 = rtems_configuration_get_microseconds_per_tick() - 1;
/* Feed system frequency to the timer */
g_timer_regs->tmr1 |= MCF5272_TMR_CLK_MSTR;
/* Configure timer1 interrupts */
icr = g_intctrl_regs->icr1;
icr = icr & ~(MCF5272_ICR1_TMR1_MASK | MCF5272_ICR1_TMR1_PI);
icr |= (MCF5272_ICR1_TMR1_IPL(BSP_INTLVL_TMR1) | MCF5272_ICR1_TMR1_PI);
g_intctrl_regs->icr1 = icr;
/* Register the driver exit procedure so we can shutdown */
atexit(Clock_exit);
}
}
int sched_rr_get_interval(
pid_t pid,
struct timespec *interval
)
{
/*
* Only supported for the "calling process" (i.e. this node).
*/
if ( pid && pid != getpid() )
rtems_set_errno_and_return_minus_one( ESRCH );
if ( !interval )
rtems_set_errno_and_return_minus_one( EINVAL );
_Timespec_From_ticks(
rtems_configuration_get_ticks_per_timeslice(),
interval
);
return 0;
}
bool _Thread_Initialize(
Thread_Information *information,
Thread_Control *the_thread,
const Scheduler_Control *scheduler,
void *stack_area,
size_t stack_size,
bool is_fp,
Priority_Control priority,
bool is_preemptible,
Thread_CPU_budget_algorithms budget_algorithm,
Thread_CPU_budget_algorithm_callout budget_callout,
uint32_t isr_level,
Objects_Name name
)
{
uintptr_t tls_size = _TLS_Get_size();
size_t actual_stack_size = 0;
void *stack = NULL;
#if ( CPU_HARDWARE_FP == TRUE ) || ( CPU_SOFTWARE_FP == TRUE )
void *fp_area = NULL;
#endif
bool extension_status;
size_t i;
bool scheduler_node_initialized = false;
Per_CPU_Control *cpu = _Per_CPU_Get_by_index( 0 );
#if defined( RTEMS_SMP )
if ( rtems_configuration_is_smp_enabled() && !is_preemptible ) {
return false;
}
#endif
memset(
&the_thread->current_state,
0,
information->Objects.size - offsetof( Thread_Control, current_state )
);
for ( i = 0 ; i < _Thread_Control_add_on_count ; ++i ) {
const Thread_Control_add_on *add_on = &_Thread_Control_add_ons[ i ];
*(void **) ( (char *) the_thread + add_on->destination_offset ) =
(char *) the_thread + add_on->source_offset;
}
/*
* Allocate and Initialize the stack for this thread.
*/
#if !defined(RTEMS_SCORE_THREAD_ENABLE_USER_PROVIDED_STACK_VIA_API)
actual_stack_size = _Thread_Stack_Allocate( the_thread, stack_size );
if ( !actual_stack_size || actual_stack_size < stack_size )
return false; /* stack allocation failed */
stack = the_thread->Start.stack;
#else
if ( !stack_area ) {
actual_stack_size = _Thread_Stack_Allocate( the_thread, stack_size );
if ( !actual_stack_size || actual_stack_size < stack_size )
return false; /* stack allocation failed */
stack = the_thread->Start.stack;
the_thread->Start.core_allocated_stack = true;
} else {
stack = stack_area;
actual_stack_size = stack_size;
the_thread->Start.core_allocated_stack = false;
}
#endif
_Stack_Initialize(
&the_thread->Start.Initial_stack,
stack,
actual_stack_size
);
/* Thread-local storage (TLS) area allocation */
if ( tls_size > 0 ) {
uintptr_t tls_align = _TLS_Heap_align_up( (uintptr_t) _TLS_Alignment );
uintptr_t tls_alloc = _TLS_Get_allocation_size( tls_size, tls_align );
the_thread->Start.tls_area =
_Workspace_Allocate_aligned( tls_alloc, tls_align );
if ( the_thread->Start.tls_area == NULL ) {
goto failed;
}
}
/*
* Allocate the floating point area for this thread
*/
#if ( CPU_HARDWARE_FP == TRUE ) || ( CPU_SOFTWARE_FP == TRUE )
if ( is_fp ) {
fp_area = _Workspace_Allocate( CONTEXT_FP_SIZE );
if ( !fp_area )
goto failed;
fp_area = _Context_Fp_start( fp_area, 0 );
}
the_thread->fp_context = fp_area;
the_thread->Start.fp_context = fp_area;
#endif
/*
* Get thread queue heads
*/
the_thread->Wait.spare_heads = _Freechain_Get(
&information->Free_thread_queue_heads,
_Workspace_Allocate,
_Objects_Extend_size( &information->Objects ),
THREAD_QUEUE_HEADS_SIZE( _Scheduler_Count )
);
if ( the_thread->Wait.spare_heads == NULL ) {
goto failed;
}
_Thread_queue_Heads_initialize( the_thread->Wait.spare_heads );
/*
* General initialization
*/
the_thread->is_fp = is_fp;
the_thread->Start.isr_level = isr_level;
the_thread->Start.is_preemptible = is_preemptible;
the_thread->Start.budget_algorithm = budget_algorithm;
the_thread->Start.budget_callout = budget_callout;
_Thread_Timer_initialize( &the_thread->Timer, cpu );
switch ( budget_algorithm ) {
case THREAD_CPU_BUDGET_ALGORITHM_NONE:
case THREAD_CPU_BUDGET_ALGORITHM_RESET_TIMESLICE:
break;
#if defined(RTEMS_SCORE_THREAD_ENABLE_EXHAUST_TIMESLICE)
case THREAD_CPU_BUDGET_ALGORITHM_EXHAUST_TIMESLICE:
the_thread->cpu_time_budget =
rtems_configuration_get_ticks_per_timeslice();
break;
#endif
#if defined(RTEMS_SCORE_THREAD_ENABLE_SCHEDULER_CALLOUT)
case THREAD_CPU_BUDGET_ALGORITHM_CALLOUT:
break;
#endif
}
#if defined(RTEMS_SMP)
RTEMS_STATIC_ASSERT( THREAD_SCHEDULER_BLOCKED == 0, Scheduler_state );
the_thread->Scheduler.own_control = scheduler;
the_thread->Scheduler.control = scheduler;
the_thread->Scheduler.own_node = the_thread->Scheduler.node;
_Resource_Node_initialize( &the_thread->Resource_node );
the_thread->Lock.current = &the_thread->Lock.Default;
_SMP_ticket_lock_Initialize( &the_thread->Lock.Default );
_SMP_lock_Stats_initialize( &the_thread->Lock.Stats, "Thread Lock" );
_SMP_lock_Stats_initialize( &the_thread->Potpourri_stats, "Thread Potpourri" );
#endif
_Thread_Debug_set_real_processor( the_thread, cpu );
/* Initialize the CPU for the non-SMP schedulers */
_Thread_Set_CPU( the_thread, cpu );
_Thread_queue_Initialize( &the_thread->Join_queue );
the_thread->current_state = STATES_DORMANT;
the_thread->Wait.operations = &_Thread_queue_Operations_default;
the_thread->current_priority = priority;
the_thread->real_priority = priority;
the_thread->Start.initial_priority = priority;
RTEMS_STATIC_ASSERT( THREAD_WAIT_FLAGS_INITIAL == 0, Wait_flags );
_Scheduler_Node_initialize( scheduler, the_thread );
scheduler_node_initialized = true;
_Scheduler_Update_priority( the_thread, priority );
/* POSIX Keys */
_RBTree_Initialize_empty( &the_thread->Keys.Key_value_pairs );
_ISR_lock_Initialize( &the_thread->Keys.Lock, "POSIX Key Value Pairs" );
_Thread_Action_control_initialize( &the_thread->Post_switch_actions );
RTEMS_STATIC_ASSERT( THREAD_LIFE_NORMAL == 0, Life_state );
/*
* Open the object
*/
_Objects_Open( &information->Objects, &the_thread->Object, name );
/*
* We assume the Allocator Mutex is locked and dispatching is
* enabled when we get here. We want to be able to run the
* user extensions with dispatching enabled. The Allocator
* Mutex provides sufficient protection to let the user extensions
* run safely.
*/
extension_status = _User_extensions_Thread_create( the_thread );
if ( extension_status )
return true;
failed:
if ( scheduler_node_initialized ) {
_Scheduler_Node_destroy( scheduler, the_thread );
}
_Workspace_Free( the_thread->Start.tls_area );
_Freechain_Put(
&information->Free_thread_queue_heads,
the_thread->Wait.spare_heads
);
#if ( CPU_HARDWARE_FP == TRUE ) || ( CPU_SOFTWARE_FP == TRUE )
_Workspace_Free( fp_area );
#endif
_Thread_Stack_Free( the_thread );
return false;
}
bool _Thread_Initialize(
Objects_Information *information,
Thread_Control *the_thread,
const Scheduler_Control *scheduler,
void *stack_area,
size_t stack_size,
bool is_fp,
Priority_Control priority,
bool is_preemptible,
Thread_CPU_budget_algorithms budget_algorithm,
Thread_CPU_budget_algorithm_callout budget_callout,
uint32_t isr_level,
Objects_Name name
)
{
uintptr_t tls_size = _TLS_Get_size();
size_t actual_stack_size = 0;
void *stack = NULL;
#if ( CPU_HARDWARE_FP == TRUE ) || ( CPU_SOFTWARE_FP == TRUE )
void *fp_area = NULL;
#endif
bool extension_status;
size_t i;
bool scheduler_node_initialized = false;
Per_CPU_Control *cpu = _Per_CPU_Get_by_index( 0 );
#if defined( RTEMS_SMP )
if ( rtems_configuration_is_smp_enabled() && !is_preemptible ) {
return false;
}
#endif
for ( i = 0 ; i < _Thread_Control_add_on_count ; ++i ) {
const Thread_Control_add_on *add_on = &_Thread_Control_add_ons[ i ];
*(void **) ( (char *) the_thread + add_on->destination_offset ) =
(char *) the_thread + add_on->source_offset;
}
/*
* Initialize the Ada self pointer
*/
#if __RTEMS_ADA__
the_thread->rtems_ada_self = NULL;
#endif
the_thread->Start.tls_area = NULL;
/*
* Allocate and Initialize the stack for this thread.
*/
#if !defined(RTEMS_SCORE_THREAD_ENABLE_USER_PROVIDED_STACK_VIA_API)
actual_stack_size = _Thread_Stack_Allocate( the_thread, stack_size );
if ( !actual_stack_size || actual_stack_size < stack_size )
return false; /* stack allocation failed */
stack = the_thread->Start.stack;
#else
if ( !stack_area ) {
actual_stack_size = _Thread_Stack_Allocate( the_thread, stack_size );
if ( !actual_stack_size || actual_stack_size < stack_size )
return false; /* stack allocation failed */
stack = the_thread->Start.stack;
the_thread->Start.core_allocated_stack = true;
} else {
stack = stack_area;
actual_stack_size = stack_size;
the_thread->Start.core_allocated_stack = false;
}
#endif
_Stack_Initialize(
&the_thread->Start.Initial_stack,
stack,
actual_stack_size
);
/* Thread-local storage (TLS) area allocation */
if ( tls_size > 0 ) {
uintptr_t tls_align = _TLS_Heap_align_up( (uintptr_t) _TLS_Alignment );
uintptr_t tls_alloc = _TLS_Get_allocation_size( tls_size, tls_align );
the_thread->Start.tls_area =
_Workspace_Allocate_aligned( tls_alloc, tls_align );
if ( the_thread->Start.tls_area == NULL ) {
goto failed;
}
}
/*
* Allocate the floating point area for this thread
*/
#if ( CPU_HARDWARE_FP == TRUE ) || ( CPU_SOFTWARE_FP == TRUE )
if ( is_fp ) {
fp_area = _Workspace_Allocate( CONTEXT_FP_SIZE );
if ( !fp_area )
goto failed;
fp_area = _Context_Fp_start( fp_area, 0 );
}
the_thread->fp_context = fp_area;
the_thread->Start.fp_context = fp_area;
#endif
/*
* Initialize the thread timer
*/
_Watchdog_Initialize( &the_thread->Timer, NULL, 0, NULL );
#ifdef __RTEMS_STRICT_ORDER_MUTEX__
/* Initialize the head of chain of held mutexes */
_Chain_Initialize_empty(&the_thread->lock_mutex);
#endif
/*
* Clear the extensions area so extension users can determine
* if they are linked to the thread. An extension user may
* create the extension long after tasks have been created
* so they cannot rely on the thread create user extension
* call. The object index starts with one, so the first extension context is
* unused.
*/
for ( i = 1 ; i <= rtems_configuration_get_maximum_extensions() ; ++i )
the_thread->extensions[ i ] = NULL;
/*
* General initialization
*/
the_thread->Start.isr_level = isr_level;
the_thread->Start.is_preemptible = is_preemptible;
the_thread->Start.budget_algorithm = budget_algorithm;
the_thread->Start.budget_callout = budget_callout;
switch ( budget_algorithm ) {
case THREAD_CPU_BUDGET_ALGORITHM_NONE:
case THREAD_CPU_BUDGET_ALGORITHM_RESET_TIMESLICE:
break;
#if defined(RTEMS_SCORE_THREAD_ENABLE_EXHAUST_TIMESLICE)
case THREAD_CPU_BUDGET_ALGORITHM_EXHAUST_TIMESLICE:
the_thread->cpu_time_budget =
rtems_configuration_get_ticks_per_timeslice();
break;
#endif
#if defined(RTEMS_SCORE_THREAD_ENABLE_SCHEDULER_CALLOUT)
case THREAD_CPU_BUDGET_ALGORITHM_CALLOUT:
break;
#endif
}
#if defined(RTEMS_SMP)
the_thread->Scheduler.state = THREAD_SCHEDULER_BLOCKED;
the_thread->Scheduler.own_control = scheduler;
the_thread->Scheduler.control = scheduler;
the_thread->Scheduler.own_node = the_thread->Scheduler.node;
_Resource_Node_initialize( &the_thread->Resource_node );
_CPU_Context_Set_is_executing( &the_thread->Registers, false );
#endif
_Thread_Debug_set_real_processor( the_thread, cpu );
/* Initialize the CPU for the non-SMP schedulers */
_Thread_Set_CPU( the_thread, cpu );
the_thread->current_state = STATES_DORMANT;
the_thread->Wait.queue = NULL;
the_thread->resource_count = 0;
the_thread->real_priority = priority;
the_thread->Start.initial_priority = priority;
_Scheduler_Node_initialize( scheduler, the_thread );
scheduler_node_initialized = true;
_Thread_Set_priority( the_thread, priority );
/*
* Initialize the CPU usage statistics
*/
#ifndef __RTEMS_USE_TICKS_FOR_STATISTICS__
_Timestamp_Set_to_zero( &the_thread->cpu_time_used );
#else
the_thread->cpu_time_used = 0;
#endif
/*
* initialize thread's key vaule node chain
*/
_Chain_Initialize_empty( &the_thread->Key_Chain );
_Thread_Action_control_initialize( &the_thread->Post_switch_actions );
_Thread_Action_initialize(
&the_thread->Life.Action,
_Thread_Life_action_handler
);
the_thread->Life.state = THREAD_LIFE_NORMAL;
the_thread->Life.terminator = NULL;
/*
* Open the object
*/
_Objects_Open( information, &the_thread->Object, name );
/*
* We assume the Allocator Mutex is locked and dispatching is
* enabled when we get here. We want to be able to run the
* user extensions with dispatching enabled. The Allocator
* Mutex provides sufficient protection to let the user extensions
* run safely.
*/
extension_status = _User_extensions_Thread_create( the_thread );
if ( extension_status )
return true;
failed:
if ( scheduler_node_initialized ) {
_Scheduler_Node_destroy( scheduler, the_thread );
}
_Workspace_Free( the_thread->Start.tls_area );
#if ( CPU_HARDWARE_FP == TRUE ) || ( CPU_SOFTWARE_FP == TRUE )
_Workspace_Free( fp_area );
#endif
_Thread_Stack_Free( the_thread );
return false;
}
int pthread_setschedparam(
pthread_t thread,
int policy,
struct sched_param *param
)
{
Thread_Control *the_thread;
Per_CPU_Control *cpu_self;
POSIX_API_Control *api;
Thread_CPU_budget_algorithms budget_algorithm;
Thread_CPU_budget_algorithm_callout budget_callout;
int eno;
Priority_Control unused;
ISR_lock_Context lock_context;
Priority_Control new_priority;
/*
* Check all the parameters
*/
if ( param == NULL ) {
return EINVAL;
}
eno = _POSIX_Thread_Translate_sched_param(
policy,
param,
&budget_algorithm,
&budget_callout
);
if ( eno != 0 ) {
return eno;
}
the_thread = _Thread_Get_interrupt_disable( thread, &lock_context );
if ( the_thread == NULL ) {
return ESRCH;
}
/*
* Actually change the scheduling policy and parameters
*/
cpu_self = _Thread_Dispatch_disable_critical( &lock_context );
_Thread_State_acquire_critical( the_thread, &lock_context );
api = the_thread->API_Extensions[ THREAD_API_POSIX ];
if ( api->schedpolicy == SCHED_SPORADIC ) {
_Watchdog_Per_CPU_remove_relative( &api->Sporadic_timer );
}
api->schedpolicy = policy;
api->schedparam = *param;
api->Attributes.schedpolicy = policy;
api->Attributes.schedparam = *param;
the_thread->budget_algorithm = budget_algorithm;
the_thread->budget_callout = budget_callout;
switch ( policy ) {
case SCHED_OTHER:
case SCHED_FIFO:
case SCHED_RR:
the_thread->cpu_time_budget =
rtems_configuration_get_ticks_per_timeslice();
new_priority = _POSIX_Priority_To_core( api->schedparam.sched_priority );
break;
case SCHED_SPORADIC:
api->ss_high_priority = api->schedparam.sched_priority;
break;
}
_Thread_State_release( the_thread, &lock_context );
switch ( policy ) {
case SCHED_OTHER:
case SCHED_FIFO:
case SCHED_RR:
_Thread_Set_priority( the_thread, new_priority, &unused, true );
break;
case SCHED_SPORADIC:
_POSIX_Threads_Sporadic_budget_TSR( &api->Sporadic_timer );
break;
}
_Thread_Dispatch_enable( cpu_self );
return 0;
}
void _Thread_Dispatch( void )
{
Per_CPU_Control *cpu_self;
Thread_Control *executing;
ISR_Level level;
#if defined( RTEMS_SMP )
/*
* On SMP the complete context switch must be atomic with respect to one
* processor. See also _Thread_Handler() since _Context_switch() may branch
* to this function.
*/
_ISR_Disable_without_giant( level );
#endif
cpu_self = _Per_CPU_Get();
_Assert( cpu_self->thread_dispatch_disable_level == 0 );
_Profiling_Thread_dispatch_disable( cpu_self, 0 );
cpu_self->thread_dispatch_disable_level = 1;
/*
* Now determine if we need to perform a dispatch on the current CPU.
*/
executing = cpu_self->executing;
#if !defined( RTEMS_SMP )
_ISR_Disable( level );
#endif
#if defined( RTEMS_SMP )
if ( cpu_self->dispatch_necessary ) {
#else
while ( cpu_self->dispatch_necessary ) {
#endif
Thread_Control *heir = _Thread_Get_heir_and_make_it_executing( cpu_self );
/*
* When the heir and executing are the same, then we are being
* requested to do the post switch dispatching. This is normally
* done to dispatch signals.
*/
if ( heir == executing )
goto post_switch;
/*
* Since heir and executing are not the same, we need to do a real
* context switch.
*/
#if __RTEMS_ADA__
executing->rtems_ada_self = rtems_ada_self;
rtems_ada_self = heir->rtems_ada_self;
#endif
if ( heir->budget_algorithm == THREAD_CPU_BUDGET_ALGORITHM_RESET_TIMESLICE )
heir->cpu_time_budget = rtems_configuration_get_ticks_per_timeslice();
#if !defined( RTEMS_SMP )
_ISR_Enable( level );
#endif
#ifndef __RTEMS_USE_TICKS_FOR_STATISTICS__
_Thread_Update_cpu_time_used(
executing,
&cpu_self->time_of_last_context_switch
);
#else
{
_TOD_Get_uptime( &cpu_self->time_of_last_context_switch );
heir->cpu_time_used++;
}
#endif
#if !defined(__DYNAMIC_REENT__)
/*
* Switch libc's task specific data.
*/
if ( _Thread_libc_reent ) {
executing->libc_reent = *_Thread_libc_reent;
*_Thread_libc_reent = heir->libc_reent;
}
#endif
_User_extensions_Thread_switch( executing, heir );
/*
* If the CPU has hardware floating point, then we must address saving
* and restoring it as part of the context switch.
*
* The second conditional compilation section selects the algorithm used
* to context switch between floating point tasks. The deferred algorithm
* can be significantly better in a system with few floating point tasks
* because it reduces the total number of save and restore FP context
* operations. However, this algorithm can not be used on all CPUs due
* to unpredictable use of FP registers by some compilers for integer
* operations.
*/
#if ( CPU_HARDWARE_FP == TRUE ) || ( CPU_SOFTWARE_FP == TRUE )
#if ( CPU_USE_DEFERRED_FP_SWITCH != TRUE )
if ( executing->fp_context != NULL )
_Context_Save_fp( &executing->fp_context );
#endif
#endif
_Context_Switch( &executing->Registers, &heir->Registers );
#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 );
_Context_Restore_fp( &executing->fp_context );
_Thread_Allocated_fp = executing;
}
#else
if ( executing->fp_context != NULL )
_Context_Restore_fp( &executing->fp_context );
#endif
#endif
/*
* We have to obtain this value again after the context switch since the
* heir thread may have migrated from another processor. Values from the
* stack or non-volatile registers reflect the old execution environment.
*/
cpu_self = _Per_CPU_Get();
_Thread_Debug_set_real_processor( executing, cpu_self );
#if !defined( RTEMS_SMP )
_ISR_Disable( level );
#endif
}
post_switch:
_Assert( cpu_self->thread_dispatch_disable_level == 1 );
cpu_self->thread_dispatch_disable_level = 0;
_Profiling_Thread_dispatch_enable( cpu_self, 0 );
_ISR_Enable_without_giant( level );
_Thread_Run_post_switch_actions( executing );
}
int pthread_setschedparam(
pthread_t thread,
int policy,
struct sched_param *param
)
{
Thread_Control *the_thread;
POSIX_API_Control *api;
Thread_CPU_budget_algorithms budget_algorithm;
Thread_CPU_budget_algorithm_callout budget_callout;
Objects_Locations location;
int rc;
/*
* Check all the parameters
*/
if ( !param )
return EINVAL;
rc = _POSIX_Thread_Translate_sched_param(
policy,
param,
&budget_algorithm,
&budget_callout
);
if ( rc )
return rc;
/*
* Actually change the scheduling policy and parameters
*/
the_thread = _Thread_Get( thread, &location );
switch ( location ) {
case OBJECTS_LOCAL:
api = the_thread->API_Extensions[ THREAD_API_POSIX ];
if ( api->schedpolicy == SCHED_SPORADIC )
(void) _Watchdog_Remove( &api->Sporadic_timer );
api->schedpolicy = policy;
api->schedparam = *param;
api->Attributes.schedpolicy = policy;
api->Attributes.schedparam = *param;
the_thread->budget_algorithm = budget_algorithm;
the_thread->budget_callout = budget_callout;
switch ( api->schedpolicy ) {
case SCHED_OTHER:
case SCHED_FIFO:
case SCHED_RR:
the_thread->cpu_time_budget =
rtems_configuration_get_ticks_per_timeslice();
the_thread->real_priority =
_POSIX_Priority_To_core( api->schedparam.sched_priority );
_Thread_Change_priority(
the_thread,
the_thread->real_priority,
true
);
break;
case SCHED_SPORADIC:
api->ss_high_priority = api->schedparam.sched_priority;
_Watchdog_Remove( &api->Sporadic_timer );
_POSIX_Threads_Sporadic_budget_TSR( 0, the_thread );
break;
}
_Objects_Put( &the_thread->Object );
return 0;
#if defined(RTEMS_MULTIPROCESSING)
case OBJECTS_REMOTE:
#endif
case OBJECTS_ERROR:
break;
}
return ESRCH;
}
void _Thread_Do_dispatch( Per_CPU_Control *cpu_self, ISR_Level level )
{
Thread_Control *executing;
_Assert( cpu_self->thread_dispatch_disable_level == 1 );
executing = cpu_self->executing;
do {
Thread_Control *heir = _Thread_Get_heir_and_make_it_executing( cpu_self );
/*
* When the heir and executing are the same, then we are being
* requested to do the post switch dispatching. This is normally
* done to dispatch signals.
*/
if ( heir == executing )
goto post_switch;
/*
* Since heir and executing are not the same, we need to do a real
* context switch.
*/
#if __RTEMS_ADA__
executing->rtems_ada_self = rtems_ada_self;
rtems_ada_self = heir->rtems_ada_self;
#endif
if ( heir->budget_algorithm == THREAD_CPU_BUDGET_ALGORITHM_RESET_TIMESLICE )
heir->cpu_time_budget = rtems_configuration_get_ticks_per_timeslice();
/*
* On SMP the complete context switch must be atomic with respect to one
* processor. See also _Thread_Handler() since _Context_switch() may branch
* to this function.
*/
#if !defined( RTEMS_SMP )
_ISR_Enable( level );
#endif
#ifndef __RTEMS_USE_TICKS_FOR_STATISTICS__
_Thread_Update_cpu_time_used(
executing,
&cpu_self->time_of_last_context_switch
);
#else
{
_TOD_Get_uptime( &cpu_self->time_of_last_context_switch );
heir->cpu_time_used++;
}
#endif
#if !defined(__DYNAMIC_REENT__)
/*
* Switch libc's task specific data.
*/
if ( _Thread_libc_reent ) {
executing->libc_reent = *_Thread_libc_reent;
*_Thread_libc_reent = heir->libc_reent;
}
#endif
_User_extensions_Thread_switch( executing, heir );
_Thread_Save_fp( executing );
_Context_Switch( &executing->Registers, &heir->Registers );
_Thread_Restore_fp( executing );
/*
* We have to obtain this value again after the context switch since the
* heir thread may have migrated from another processor. Values from the
* stack or non-volatile registers reflect the old execution environment.
*/
cpu_self = _Per_CPU_Get();
_Thread_Debug_set_real_processor( executing, cpu_self );
#if !defined( RTEMS_SMP )
_ISR_Disable( level );
#endif
} while (
#if defined( RTEMS_SMP )
false
#else
cpu_self->dispatch_necessary
#endif
);
post_switch:
_Assert( cpu_self->thread_dispatch_disable_level == 1 );
cpu_self->thread_dispatch_disable_level = 0;
_Profiling_Thread_dispatch_enable( cpu_self, 0 );
_ISR_Enable_without_giant( level );
_Thread_Run_post_switch_actions( executing );
}
rtems_status_code rtems_task_mode(
rtems_mode mode_set,
rtems_mode mask,
rtems_mode *previous_mode_set
)
{
Thread_Control *executing;
RTEMS_API_Control *api;
ASR_Information *asr;
bool preempt_enabled;
bool needs_asr_dispatching;
rtems_mode old_mode;
if ( !previous_mode_set )
return RTEMS_INVALID_ADDRESS;
executing = _Thread_Get_executing();
api = executing->API_Extensions[ THREAD_API_RTEMS ];
asr = &api->Signal;
old_mode = (executing->is_preemptible) ? RTEMS_PREEMPT : RTEMS_NO_PREEMPT;
if ( executing->budget_algorithm == THREAD_CPU_BUDGET_ALGORITHM_NONE )
old_mode |= RTEMS_NO_TIMESLICE;
else
old_mode |= RTEMS_TIMESLICE;
old_mode |= (asr->is_enabled) ? RTEMS_ASR : RTEMS_NO_ASR;
old_mode |= _ISR_Get_level();
*previous_mode_set = old_mode;
/*
* These are generic thread scheduling characteristics.
*/
preempt_enabled = false;
if ( mask & RTEMS_PREEMPT_MASK ) {
#if defined( RTEMS_SMP )
if ( rtems_configuration_is_smp_enabled() &&
!_Modes_Is_preempt( mode_set ) ) {
return RTEMS_NOT_IMPLEMENTED;
}
#endif
bool is_preempt_enabled = _Modes_Is_preempt( mode_set );
preempt_enabled = !executing->is_preemptible && is_preempt_enabled;
executing->is_preemptible = is_preempt_enabled;
}
if ( mask & RTEMS_TIMESLICE_MASK ) {
if ( _Modes_Is_timeslice(mode_set) ) {
executing->budget_algorithm = THREAD_CPU_BUDGET_ALGORITHM_RESET_TIMESLICE;
executing->cpu_time_budget =
rtems_configuration_get_ticks_per_timeslice();
} else
executing->budget_algorithm = THREAD_CPU_BUDGET_ALGORITHM_NONE;
}
/*
* Set the new interrupt level
*/
if ( mask & RTEMS_INTERRUPT_MASK )
_Modes_Set_interrupt_level( mode_set );
/*
* This is specific to the RTEMS API
*/
needs_asr_dispatching = false;
if ( mask & RTEMS_ASR_MASK ) {
bool is_asr_enabled = !_Modes_Is_asr_disabled( mode_set );
if ( is_asr_enabled != asr->is_enabled ) {
asr->is_enabled = is_asr_enabled;
_ASR_Swap_signals( asr );
if ( _ASR_Are_signals_pending( asr ) ) {
needs_asr_dispatching = true;
_Thread_Add_post_switch_action(
executing,
&api->Signal_action,
_Signal_Action_handler
);
}
}
}
if ( preempt_enabled || needs_asr_dispatching ) {
Per_CPU_Control *cpu_self;
ISR_lock_Context lock_context;
cpu_self = _Thread_Dispatch_disable();
_Scheduler_Acquire( executing, &lock_context );
_Scheduler_Schedule( executing );
_Scheduler_Release( executing, &lock_context );
_Thread_Dispatch_enable( cpu_self );
}
return RTEMS_SUCCESSFUL;
}
static int _POSIX_Set_sched_param(
Thread_Control *the_thread,
int policy,
struct sched_param *param,
Thread_CPU_budget_algorithms budget_algorithm,
Thread_CPU_budget_algorithm_callout budget_callout,
Thread_queue_Context *queue_context
)
{
const Scheduler_Control *scheduler;
POSIX_API_Control *api;
int normal_prio;
int low_prio;
bool valid;
Priority_Control core_normal_prio;
Priority_Control core_low_prio;
normal_prio = param->sched_priority;
scheduler = _Thread_Scheduler_get_home( the_thread );
core_normal_prio = _POSIX_Priority_To_core( scheduler, normal_prio, &valid );
if ( !valid ) {
return EINVAL;
}
if ( policy == SCHED_SPORADIC ) {
low_prio = param->sched_ss_low_priority;
} else {
low_prio = normal_prio;
}
core_low_prio = _POSIX_Priority_To_core( scheduler, low_prio, &valid );
if ( !valid ) {
return EINVAL;
}
api = the_thread->API_Extensions[ THREAD_API_POSIX ];
_Watchdog_Per_CPU_remove_monotonic( &api->Sporadic.Timer );
_Priority_Node_set_priority( &the_thread->Real_priority, core_normal_prio );
if ( _Priority_Node_is_active( &api->Sporadic.Low_priority ) ) {
_Thread_Priority_add(
the_thread,
&the_thread->Real_priority,
queue_context
);
_Thread_Priority_remove(
the_thread,
&api->Sporadic.Low_priority,
queue_context
);
_Priority_Node_set_inactive( &api->Sporadic.Low_priority );
} else {
_Thread_Priority_changed(
the_thread,
&the_thread->Real_priority,
false,
queue_context
);
}
the_thread->budget_algorithm = budget_algorithm;
the_thread->budget_callout = budget_callout;
_Priority_Node_set_priority( &api->Sporadic.Low_priority, core_low_prio );
api->Sporadic.sched_ss_repl_period = param->sched_ss_repl_period;
api->Sporadic.sched_ss_init_budget = param->sched_ss_init_budget;
api->Sporadic.sched_ss_max_repl = param->sched_ss_max_repl;
if ( policy == SCHED_SPORADIC ) {
_POSIX_Threads_Sporadic_timer_insert( the_thread, api );
} else {
the_thread->cpu_time_budget =
rtems_configuration_get_ticks_per_timeslice();
}
return 0;
}
