incubator-nuttx/sched/pthread/pthread_getschedparam.c

131 lines
4.8 KiB
C

/****************************************************************************
* sched/pthread/pthread_getschedparam.c
*
* Copyright (C) 2007, 2008, 2015, 2018 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 <nuttx/config.h>
#include <sys/types.h>
#include <pthread.h>
#include <sched.h>
#include <errno.h>
#include <debug.h>
#include <nuttx/sched.h>
#include "pthread/pthread.h"
/****************************************************************************
* 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.
*
* Input 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.
*
* Returned 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;
sinfo("Thread ID=%d policy=0x%p param=0x%p\n", thread, policy, param);
if (policy == NULL || param == NULL)
{
ret = EINVAL;
}
else
{
/* Get the scheduler parameters of the thread. */
ret = nxsched_getparam((pid_t)thread, param);
if (ret < 0)
{
ret = -ret;
}
else
{
/* Get the scheduler policy. */
ret = nxsched_getscheduler((pid_t)thread);
if (ret < 0)
{
ret = -ret;
}
else
{
*policy = ret;
ret = OK;
}
}
}
sinfo("Returning %d\n", ret);
return ret;
}