nuttx/sched/sched/sched_getaffinity.c
Alin Jerpelea 8935ac4cc3 sched: Author Gregory Nutt: update licenses to Apache
Gregory Nutt has submitted the SGA and we can mograte the licenses
to Apache.

Signed-off-by: Alin Jerpelea <alin.jerpelea@sony.com>
2021-02-09 01:21:53 -08:00

140 lines
4.4 KiB
C

/****************************************************************************
* sched/sched/sched_getaffinity.c
*
* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright ownership. The
* ASF licenses this file to you under the Apache License, Version 2.0 (the
* "License"); you may not use this file except in compliance with the
* License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
* WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
* License for the specific language governing permissions and limitations
* under the License.
*
****************************************************************************/
/****************************************************************************
* Included Files
****************************************************************************/
#include <nuttx/config.h>
#include <sys/types.h>
#include <sched.h>
#include <assert.h>
#include <errno.h>
#include <nuttx/sched.h>
#include "sched/sched.h"
/****************************************************************************
* Public Functions
****************************************************************************/
/****************************************************************************
* Name: nxsched_get_affinity
*
* Description:
* nxsched_get_affinity() writes the affinity mask of the thread whose ID
* is pid into the cpu_set_t pointed to by mask. The cpusetsize
* argument specifies the size (in bytes) of mask. If pid is zero, then
* the mask of the calling thread is returned.
*
* nxsched_get_affinity() is identical to the function sched_getaffinity(),
* differing only in its return value: This function does not modify the
* errno variable.
*
* This is a non-standard, internal OS function and is not intended for
* use by application logic. Applications should use the standard
* sched_getparam().
*
* Input Parameters:
* pid - The ID of thread whose affinity set will be retrieved.
* cpusetsize - Size of mask. MUST be sizeofcpu_set_t().
* mask - The location to return the thread's new affinity set.
*
* Returned Value:
* Zero (OK) if successful. Otherwise, a negated errno value is returned:
*
* ESRCH The task whose ID is pid could not be found.
*
****************************************************************************/
int nxsched_get_affinity(pid_t pid, size_t cpusetsize, FAR cpu_set_t *mask)
{
FAR struct tcb_s *tcb;
int ret;
DEBUGASSERT(cpusetsize == sizeof(cpu_set_t) && mask != NULL);
/* Verify that the PID corresponds to a real task */
sched_lock();
if (pid == 0)
{
tcb = this_task();
}
else
{
tcb = nxsched_get_tcb(pid);
}
if (tcb == NULL)
{
ret = -ESRCH;
}
else
{
/* Return the affinity mask from the TCB. */
*mask = tcb->affinity;
ret = OK;
}
sched_unlock();
return ret;
}
/****************************************************************************
* Name: sched_getaffinity
*
* Description:
* sched_getaffinity() writes the affinity mask of the thread whose ID
* is pid into the cpu_set_t pointed to by mask. The cpusetsize
* argument specifies the size (in bytes) of mask. If pid is zero, then
* the mask of the calling thread is returned.
*
* This function is a simply wrapper around nxsched_get_affinity() that
* sets the errno value in the event of an error.
*
* Input Parameters:
* pid - The ID of thread whose affinity set will be retrieved.
* cpusetsize - Size of mask. MUST be sizeofcpu_set_t().
* mask - The location to return the thread's new affinity set.
*
* Returned Value:
* 0 if successful. Otherwise, ERROR (-1) is returned, and errno is
* set appropriately:
*
* ESRCH The task whose ID is pid could not be found.
*
****************************************************************************/
int sched_getaffinity(pid_t pid, size_t cpusetsize, FAR cpu_set_t *mask)
{
int ret = nxsched_get_affinity(pid, cpusetsize, mask);
if (ret < 0)
{
set_errno(-ret);
ret = ERROR;
}
return ret;
}