/************************************************************
* pthread_create.c
*
* Copyright (C) 2007 Gregory Nutt. All rights reserved.
* Author: Gregory Nutt <spudmonkey@racsa.co.cr>
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in
* the documentation and/or other materials provided with the
* distribution.
* 3. Neither the name Gregory Nutt nor the names of its contributors may be
* used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
* FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
* COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
* BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
* OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
* AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
* ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
* POSSIBILITY OF SUCH DAMAGE.
*
************************************************************/
/************************************************************
* Included Files
************************************************************/
#include <nuttx/config.h>
#include <sys/types.h>
#include <pthread.h>
#include <sched.h>
#include <debug.h>
#include <errno.h>
#include <queue.h>
#include <nuttx/kmalloc.h>
#include <nuttx/arch.h>
#include "os_internal.h"
#include "pthread_internal.h"
/************************************************************
* Definitions
************************************************************/
/************************************************************
* Private Type Declarations
************************************************************/
/************************************************************
* Global Variables
************************************************************/
/* Default pthread attributes */
pthread_attr_t g_default_pthread_attr =
{
.stacksize = PTHREAD_STACK_DEFAULT,
.priority = PTHREAD_DEFAULT_PRIORITY,
.policy = SCHED_RR,
.inheritsched = PTHREAD_EXPLICIT_SCHED,
};
/************************************************************
* Private Variables
************************************************************/
/************************************************************
* Private Functions
************************************************************/
/************************************************************
* Function: pthread_addjoininfo
*
* Description:
* Add a join_t to the local data set.
*
* Parameters:
* pjoin
*
* Return Value:
* None or pointer to the found entry.
*
* Assumptions:
* The caller has provided protection from re-entrancy.
*
************************************************************/
static void pthread_addjoininfo(join_t *pjoin)
{
pjoin->next = NULL;
if (!g_pthread_tail)
{
g_pthread_head = pjoin;
}
else
{
g_pthread_tail->next = pjoin;
}
g_pthread_tail = pjoin;
}
/************************************************************
* Name: pthread_start
*
* Description:
* This function is the low level entry point into the
* pthread
*
* Parameters:
* None
*
************************************************************/
static void pthread_start(void)
{
_TCB *ptcb = (_TCB*)g_readytorun.head;
join_t *pjoin = (join_t*)ptcb->joininfo;
pthread_addr_t exit_status;
/* Sucessfully spawned, add the pjoin to our data set.
* Don't re-enable pre-emption until this is done.
*/
(void)pthread_takesemaphore(&g_join_semaphore);
pthread_addjoininfo(pjoin);
(void)pthread_givesemaphore(&g_join_semaphore);
/* Report to the spawner that we successfully started. */
pjoin->started = TRUE;
(void)pthread_givesemaphore(&pjoin->data_sem);
/* Pass control to the thread entry point. The argument is
* argv[1]. argv[0] (the thread name) and argv[2-4] are not made
* available to the pthread.
*/
exit_status = (*ptcb->entry.pthread)((pthread_addr_t)ptcb->argv[1]);
/* The thread has returned */
pthread_exit(exit_status);
}
/************************************************************
* Public Functions
************************************************************/
/************************************************************
* Name: pthread_create
*
* Description:
* This function creates and activates a new thread with a
* specified attributes.
*
* Input Parameters:
* thread
* attr
* startRoutine
* arg
************************************************************/
int pthread_create(pthread_t *thread, pthread_attr_t *attr,
pthread_startroutine_t startRoutine,
pthread_addr_t arg)
{
_TCB *ptcb;
join_t *pjoin;
STATUS status;
int priority;
#if CONFIG_RR_INTERVAL > 0
int policy;
#endif
pid_t pid;
/* If attributes were not supplied, use the default attributes */
if (!attr)
{
attr = &g_default_pthread_attr;
}
/* Allocate a TCB for the new task. */
ptcb = (_TCB*)kzmalloc(sizeof(_TCB));
if (!ptcb)
{
*get_errno_ptr() = ENOMEM;
return ERROR;
}
/* Associate file descriptors with the new task */
if (sched_setuppthreadfiles(ptcb) != OK)
{
sched_releasetcb(ptcb);
return ERROR;
}
/* Allocate a detachable structure to support pthread_join logic */
pjoin = (join_t*)kzmalloc(sizeof(join_t));
if (!pjoin)
{
sched_releasetcb(ptcb);
return ERROR;
}
/* Allocate the stack for the TCB */
status = up_create_stack(ptcb, attr->stacksize);
if (status != OK)
{
sched_releasetcb(ptcb);
sched_free(pjoin);
return ERROR;
}
/* Should we use the priority and scheduler specified in the
* pthread attributes? Or should we use the current thread's
* priority and scheduler?
*/
if (attr->inheritsched == PTHREAD_INHERIT_SCHED)
{
/* Get the priority of this thread. */
struct sched_param param;
status = sched_getparam(0, ¶m);
if (status == OK)
{
priority = param.sched_priority;
}
/* Get the scheduler policy for this thread */
#if CONFIG_RR_INTERVAL > 0
policy = sched_getscheduler(0);
if (policy == ERROR)
{
policy = SCHED_FIFO;
}
#endif
}
else
{
/* Use the priority and scheduler from the attributes */
priority = attr->priority;
#if CONFIG_RR_INTERVAL > 0
policy = attr->policy;
#endif
}
/* Initialize the task */
status = _task_init(ptcb, NULL, priority, pthread_start, (main_t)startRoutine,
TRUE, (char*)arg, NULL, NULL, NULL);
if (status != OK)
{
sched_releasetcb(ptcb);
sched_free(pjoin);
return ERROR;
}
/* Attach the join info to the TCB. */
ptcb->joininfo = (void*)pjoin;
/* If round robin scheduling is selected, set the appropriate flag
* in the TCB.
*/
#if CONFIG_RR_INTERVAL > 0
if (policy == SCHED_RR)
{
ptcb->flags |= TCB_FLAG_ROUND_ROBIN;
ptcb->timeslice = CONFIG_RR_INTERVAL;
}
#endif
/* Get the assigned pid before we start the task (who knows what
* could happen to ptcb after this!). Copy this ID into the join structure
* as well.
*/
pid = (int)ptcb->pid;
pjoin->thread.pid = pid;
/* Initialize the semaphores in the join structure to zero. */
status = sem_init(&pjoin->data_sem, 0, 0);
if (status == OK) status = sem_init(&pjoin->exit_sem, 0, 0);
/* Activate the task */
sched_lock();
if (status == OK)
{
status = task_activate(ptcb);
}
if (status == OK)
{
/* Wait for the task to actually get running and to register
* its join_t
*/
(void)pthread_takesemaphore(&pjoin->data_sem);
/* Return the thread information to the caller */
if (thread) thread->pid = pid;
if (!pjoin->started) status = ERROR;
sched_unlock();
(void)sem_destroy(&pjoin->data_sem);
}
else
{
sched_unlock();
dq_rem((dq_entry_t*)ptcb, &g_inactivetasks);
(void)sem_destroy(&pjoin->data_sem);
(void)sem_destroy(&pjoin->exit_sem);
sched_releasetcb(ptcb);
sched_free(pjoin);
return ERROR;
}
return OK;
}
