134 lines
4.0 KiB
C
134 lines
4.0 KiB
C
/****************************************************************************
|
|
* sched/semaphore/sem_waitirq.c
|
|
*
|
|
* SPDX-License-Identifier: Apache-2.0
|
|
*
|
|
* 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 <sched.h>
|
|
#include <assert.h>
|
|
#include <errno.h>
|
|
|
|
#include <nuttx/addrenv.h>
|
|
#include <nuttx/irq.h>
|
|
#include <nuttx/arch.h>
|
|
|
|
#include "sched/sched.h"
|
|
#include "semaphore/semaphore.h"
|
|
|
|
/****************************************************************************
|
|
* Public Functions
|
|
****************************************************************************/
|
|
|
|
/****************************************************************************
|
|
* Name: nxsem_wait_irq
|
|
*
|
|
* Description:
|
|
* This function is called when either:
|
|
*
|
|
* 1. A signal is received by a task that is waiting on a semaphore.
|
|
* According to the POSIX spec, "...the calling thread shall not return
|
|
* from the call to [nxsem_wait] until it either locks the semaphore or
|
|
* the call is interrupted by a signal."
|
|
* 2. From logic associated with sem_timedwait(). This function is called
|
|
* when the timeout elapses without receiving the semaphore.
|
|
*
|
|
* Note: this function should used within critical_section
|
|
*
|
|
* Input Parameters:
|
|
* wtcb - A pointer to the TCB of the task that is waiting on a
|
|
* semphaphore, but has received a signal or timeout instead.
|
|
* errcode - EINTR if the semaphore wait was awakened by a signal;
|
|
* ETIMEDOUT if awakened by a timeout
|
|
*
|
|
* Returned Value:
|
|
* None
|
|
*
|
|
* Assumptions:
|
|
*
|
|
****************************************************************************/
|
|
|
|
void nxsem_wait_irq(FAR struct tcb_s *wtcb, int errcode)
|
|
{
|
|
FAR struct tcb_s *rtcb = this_task();
|
|
FAR sem_t *sem = wtcb->waitobj;
|
|
|
|
#ifdef CONFIG_ARCH_ADDRENV
|
|
FAR struct addrenv_s *oldenv;
|
|
|
|
if (wtcb->addrenv_own)
|
|
{
|
|
addrenv_select(wtcb->addrenv_own, &oldenv);
|
|
}
|
|
#endif
|
|
|
|
/* It is possible that an interrupt/context switch beat us to the punch
|
|
* and already changed the task's state.
|
|
*/
|
|
|
|
DEBUGASSERT(sem != NULL && sem->semcount < 0);
|
|
|
|
/* Restore the correct priority of all threads that hold references
|
|
* to this semaphore.
|
|
*/
|
|
|
|
nxsem_canceled(wtcb, sem);
|
|
|
|
/* And increment the count on the semaphore. This releases the count
|
|
* that was taken by sem_post(). This count decremented the semaphore
|
|
* count to negative and caused the thread to be blocked in the first
|
|
* place.
|
|
*/
|
|
|
|
sem->semcount++;
|
|
|
|
/* Remove task from waiting list */
|
|
|
|
dq_rem((FAR dq_entry_t *)wtcb, SEM_WAITLIST(sem));
|
|
|
|
#ifdef CONFIG_ARCH_ADDRENV
|
|
if (wtcb->addrenv_own)
|
|
{
|
|
addrenv_restore(oldenv);
|
|
}
|
|
#endif
|
|
|
|
/* Indicate that the wait is over. */
|
|
|
|
wtcb->waitobj = NULL;
|
|
|
|
/* Mark the errno value for the thread. */
|
|
|
|
wtcb->errcode = errcode;
|
|
|
|
/* Add the task to ready-to-run task list and
|
|
* perform the context switch if one is needed
|
|
*/
|
|
|
|
if (nxsched_add_readytorun(wtcb))
|
|
{
|
|
up_switch_context(wtcb, rtcb);
|
|
}
|
|
}
|