/*
* 16.1.2 Thread Creation, P1003.1c/Draft 10, p. 144
*
* COPYRIGHT (c) 1989-1999.
* 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.OARcorp.com/rtems/license.html.
*
* $Id$
*/
#if HAVE_CONFIG_H
#include "config.h"
#endif
#include <pthread.h>
#include <errno.h>
#include <rtems/system.h>
#include <rtems/score/thread.h>
#include <rtems/posix/pthread.h>
#include <rtems/posix/priority.h>
#include <rtems/posix/time.h>
int pthread_create(
pthread_t *thread,
const pthread_attr_t *attr,
void *(*start_routine)( void * ),
void *arg
)
{
const pthread_attr_t *the_attr;
Priority_Control core_priority;
Thread_CPU_budget_algorithms budget_algorithm;
Thread_CPU_budget_algorithm_callout budget_callout;
boolean is_fp;
boolean status;
Thread_Control *the_thread;
POSIX_API_Control *api;
int schedpolicy = SCHED_RR;
struct sched_param schedparam;
the_attr = (attr) ? attr : &_POSIX_Threads_Default_attributes;
if ( !the_attr->is_initialized )
return EINVAL;
/*
* Core Thread Initialize insures we get the minimum amount of
* stack space if it is allowed to allocate it itself.
*/
if ( the_attr->stackaddr && !_Stack_Is_enough( the_attr->stacksize ) )
return EINVAL;
#if 0
int cputime_clock_allowed; /* see time.h */
POSIX_NOT_IMPLEMENTED();
#endif
/*
* P1003.1c/Draft 10, p. 121.
*
* If inheritsched is set to PTHREAD_INHERIT_SCHED, then this thread
* inherits scheduling attributes from the creating thread. If it is
* PTHREAD_EXPLICIT_SCHED, then scheduling parameters come from the
* attributes structure.
*/
switch ( the_attr->inheritsched ) {
case PTHREAD_INHERIT_SCHED:
api = _Thread_Executing->API_Extensions[ THREAD_API_POSIX ];
schedpolicy = api->schedpolicy;
schedparam = api->schedparam;
break;
case PTHREAD_EXPLICIT_SCHED:
schedpolicy = the_attr->schedpolicy;
schedparam = the_attr->schedparam;
break;
default:
return EINVAL;
}
/*
* Check the contentionscope since rtems only supports PROCESS wide
* contention (i.e. no system wide contention).
*/
if ( the_attr->contentionscope != PTHREAD_SCOPE_PROCESS )
return ENOTSUP;
/*
* Interpret the scheduling parameters.
*/
if ( !_POSIX_Priority_Is_valid( schedparam.sched_priority ) )
return EINVAL;
core_priority = _POSIX_Priority_To_core( schedparam.sched_priority );
/*
* Set the core scheduling policy information.
*/
budget_callout = NULL;
budget_algorithm = THREAD_CPU_BUDGET_ALGORITHM_NONE;
switch ( schedpolicy ) {
case SCHED_OTHER:
budget_algorithm = THREAD_CPU_BUDGET_ALGORITHM_RESET_TIMESLICE;
break;
case SCHED_FIFO:
budget_algorithm = THREAD_CPU_BUDGET_ALGORITHM_NONE;
break;
case SCHED_RR:
budget_algorithm = THREAD_CPU_BUDGET_ALGORITHM_EXHAUST_TIMESLICE;
break;
case SCHED_SPORADIC:
budget_algorithm = THREAD_CPU_BUDGET_ALGORITHM_CALLOUT;
budget_callout = _POSIX_Threads_Sporadic_budget_callout;
if ( _POSIX_Timespec_to_interval( &schedparam.ss_replenish_period ) <
_POSIX_Timespec_to_interval( &schedparam.ss_initial_budget ) )
return EINVAL;
if ( !_POSIX_Priority_Is_valid( schedparam.ss_low_priority ) )
return EINVAL;
break;
default:
return EINVAL;
}
/*
* Currently all POSIX threads are floating point if the hardware
* supports it.
*/
#if ( CPU_HARDWARE_FP == TRUE ) || ( CPU_SOFTWARE_FP == TRUE )
is_fp = TRUE;
#else
is_fp = FALSE;
#endif
/*
* Disable dispatch for protection
*/
_Thread_Disable_dispatch();
/*
* Allocate the thread control block.
*
* NOTE: Global threads are not currently supported.
*/
the_thread = _POSIX_Threads_Allocate();
if ( !the_thread ) {
_Thread_Enable_dispatch();
return EAGAIN;
}
/*
* Initialize the core thread for this task.
*/
status = _Thread_Initialize(
&_POSIX_Threads_Information,
the_thread,
the_attr->stackaddr,
the_attr->stacksize,
is_fp,
core_priority,
TRUE, /* preemptible */
budget_algorithm,
budget_callout,
0, /* isr level */
NULL /* posix threads don't have a name */
);
if ( !status ) {
_POSIX_Threads_Free( the_thread );
_Thread_Enable_dispatch();
return EAGAIN;
}
/*
* finish initializing the per API structure
*/
api = the_thread->API_Extensions[ THREAD_API_POSIX ];
api->Attributes = *the_attr;
api->detachstate = the_attr->detachstate;
api->schedpolicy = schedpolicy;
api->schedparam = schedparam;
/*
* This insures we evaluate the process-wide signals pending when we
* first run.
*
* NOTE: Since the thread starts with all unblocked, this is necessary.
*/
the_thread->do_post_task_switch_extension = TRUE;
/*
* POSIX threads are allocated and started in one operation.
*/
status = _Thread_Start(
the_thread,
THREAD_START_POINTER,
start_routine,
arg,
0 /* unused */
);
if ( schedpolicy == SCHED_SPORADIC ) {
_Watchdog_Insert_ticks(
&api->Sporadic_timer,
_POSIX_Timespec_to_interval( &api->schedparam.ss_replenish_period )
);
}
/*
* _Thread_Start only fails if the thread was in the incorrect state
*/
if ( !status ) {
_POSIX_Threads_Free( the_thread );
_Thread_Enable_dispatch();
return EINVAL;
}
/*
* Return the id and indicate we successfully created the thread
*/
*thread = the_thread->Object.id;
_Thread_Enable_dispatch();
return 0;
}
