/**
* @file
*
* @brief Function sets scheduling policy and parameters of the thread
* @ingroup POSIXAPI
*/
/*
* 13.5.2 Dynamic Thread Scheduling Parameters Access,
* P1003.1c/Draft 10, p. 124
*/
/* COPYRIGHT (c) 1989-2014.
* 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 <pthread.h>
#include <errno.h>
#include <rtems/posix/pthreadimpl.h>
#include <rtems/posix/priorityimpl.h>
#include <rtems/score/threadimpl.h>
#include <rtems/score/schedulerimpl.h>
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 low_prio;
int high_prio;
bool valid;
Priority_Control core_normal_prio;
Priority_Control core_low_prio;
if ( policy == SCHED_SPORADIC ) {
low_prio = param->sched_ss_low_priority;
high_prio = param->sched_priority;
} else {
low_prio = param->sched_priority;
high_prio = low_prio;
}
scheduler = _Thread_Scheduler_get_home( the_thread );
core_normal_prio = _POSIX_Priority_To_core( scheduler, low_prio, &valid );
if ( !valid ) {
return EINVAL;
}
core_low_prio = _POSIX_Priority_To_core( scheduler, high_prio, &valid );
if ( !valid ) {
return EINVAL;
}
api = the_thread->API_Extensions[ THREAD_API_POSIX ];
_Watchdog_Per_CPU_remove_relative( &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
);
}
api->schedpolicy = policy;
api->schedparam = *param;
the_thread->budget_algorithm = budget_algorithm;
the_thread->budget_callout = budget_callout;
if ( policy == SCHED_SPORADIC ) {
_Priority_Node_set_priority( &api->Sporadic.Low_priority, core_low_prio );
_POSIX_Threads_Sporadic_timer_insert( the_thread, api );
} else {
the_thread->cpu_time_budget =
rtems_configuration_get_ticks_per_timeslice();
}
return 0;
}
int pthread_setschedparam(
pthread_t thread,
int policy,
struct sched_param *param
)
{
Thread_CPU_budget_algorithms budget_algorithm;
Thread_CPU_budget_algorithm_callout budget_callout;
Thread_Control *the_thread;
Per_CPU_Control *cpu_self;
Thread_queue_Context queue_context;
int error;
if ( param == NULL ) {
return EINVAL;
}
error = _POSIX_Thread_Translate_sched_param(
policy,
param,
&budget_algorithm,
&budget_callout
);
if ( error != 0 ) {
return error;
}
_Thread_queue_Context_initialize( &queue_context );
_Thread_queue_Context_clear_priority_updates( &queue_context );
the_thread = _Thread_Get( thread, &queue_context.Lock_context.Lock_context );
if ( the_thread == NULL ) {
return ESRCH;
}
_Thread_Wait_acquire_critical( the_thread, &queue_context );
error = _POSIX_Set_sched_param(
the_thread,
policy,
param,
budget_algorithm,
budget_callout,
&queue_context
);
cpu_self = _Thread_queue_Dispatch_disable( &queue_context );
_Thread_Wait_release( the_thread, &queue_context );
_Thread_Priority_update( &queue_context );
_Thread_Dispatch_enable( cpu_self );
return error;
}