/****************************************************************************
* pthread_getschedparam.c
*
* Copyright (C) 2007, 2008 Gregory Nutt. All rights reserved.
* Author: Gregory Nutt <gnutt@nuttx.org>
*
* 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 NuttX 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 <sys/types.h>
#include <pthread.h>
#include <sched.h>
#include <errno.h>
#include <debug.h>
#include "pthread_internal.h"
/****************************************************************************
* Definitions
****************************************************************************/
/****************************************************************************
* Private Type Declarations
****************************************************************************/
/****************************************************************************
* Global Variables
****************************************************************************/
/****************************************************************************
* Private Variables
****************************************************************************/
/****************************************************************************
* Private Functions
****************************************************************************/
/****************************************************************************
* Public Functions
*****************************************************************************/
/****************************************************************************
* Name: pthread_getschedparam
*
* Description:
* The pthread_getschedparam() functions will get the scheduling policy and
* parameters of threads. For SCHED_FIFO and SCHED_RR, the only required
* member of the sched_param structure is the priority sched_priority.
*
* The pthread_getschedparam() function will retrieve the scheduling
* policy and scheduling parameters for the thread whose thread ID is
* given by 'thread' and will store those values in 'policy' and 'param',
* respectively. The priority value returned from pthread_getschedparam()
* will be the value specified by the most recent pthread_setschedparam(),
* pthread_setschedprio(), or pthread_create() call affecting the target
* thread. It will not reflect any temporary adjustments to its priority
* (such as might result of any priority inheritance, for example).
*
* The policy parameter may have the value SCHED_FIFO, or SCHED_RR
* (SCHED_OTHER and SCHED_SPORADIC, in particular, are not supported).
* The SCHED_FIFO and SCHED_RR policies will have a single scheduling
* parameter, sched_priority.
*
* Parameters:
* thread - The ID of thread whose scheduling parameters will be queried.
* policy - The location to store the thread's scheduling policy.
* param - The location to store the thread's priority.
*
* Return Value:
* 0 if successful. Otherwise, the error code ESRCH if the value specified
* by thread does not refer to an existing thread.
*
* Assumptions:
*
****************************************************************************/
int pthread_getschedparam(pthread_t thread, FAR int *policy,
FAR struct sched_param *param)
{
int ret;
sdbg("Thread ID=%d policy=0x%p param=0x%p\n", thread, policy, param);
if (!policy || !param)
{
ret = EINVAL;
}
else
{
/* Get the schedparams of the thread. */
ret = sched_getparam((pid_t)thread, param);
if (ret != OK)
{
ret = EINVAL;
}
/* Return the policy. */
*policy = sched_getscheduler((pid_t)thread);
if (*policy == ERROR)
{
ret = get_errno();
}
}
sdbg("Returning %d\n", ret);
return ret;
}
