|
|
/****************************************************************************
* pthread_schedsetprio.c
*
* Copyright (C) 2007, 2009 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 <sched.h>
#include <errno.h>
#include <nuttx/arch.h>
#include "os_internal.h"
/****************************************************************************
* Definitions
****************************************************************************/
/****************************************************************************
* Private Type Declarations
****************************************************************************/
/****************************************************************************
* Global Variables
****************************************************************************/
/****************************************************************************
* Private Variables
****************************************************************************/
/****************************************************************************
* Private Function Prototypes
****************************************************************************/
/****************************************************************************
* Private Functions
****************************************************************************/
/****************************************************************************
* Public Functions
****************************************************************************/
/****************************************************************************
* Name: pthread_setsetprio
*
* Description:
* The pthread_setschedprio() function sets the scheduling priority for the
* thread whose thread ID is given by 'thread' to the value given by 'prio'.
* If the thread_setschedprio() function fails, the scheduling priority
* of the target thread will not be changed.
*
* Inputs:
* thread - the thread ID of the task to reprioritize.
* prio - The new thread priority. The range of valid priority numbers is
* from SCHED_PRIORITY_MIN through SCHED_PRIORITY_MAX.
*
* Return Value:
* OK if successful, otherwise an error number. This function can
* fail for the following reasons:
*
* EINVAL - prio is out of range.
* ESRCH - thread ID does not correspond to any thread.
*
* Assumptions:
*
****************************************************************************/
int pthread_setschedprio(pthread_t thread, int prio)
{
struct sched_param param;
int ret;
/* Set the errno to some non-zero value (failsafe) */
errno = EINVAL;
/* Call sched_setparam() to change the priority */
param.sched_priority = prio;
ret = sched_setparam((pid_t)thread, ¶m);
if (ret != OK)
{
/* If sched_setparam() fails, return the errno */
ret = errno;
}
return ret;
}
|
