incubator-nuttx/sched/semaphore/sem_timeout.c

84 lines
2.5 KiB
C

/****************************************************************************
* sched/semaphore/sem_timeout.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 <errno.h>
#include <nuttx/sched.h>
#include <nuttx/wdog.h>
#include <nuttx/irq.h>
#include "semaphore/semaphore.h"
/****************************************************************************
* Public Functions
****************************************************************************/
/****************************************************************************
* Name: nxsem_timeout
*
* Description:
* This function is called if the timeout elapses before before a
* semaphore is acquired.
*
* Input Parameters:
* arg - The argument that was provided when the timeout was configured.
*
* Returned Value:
* None
*
* Assumptions:
* - Called from the context of the timer interrupt handler.
*
****************************************************************************/
void nxsem_timeout(wdparm_t arg)
{
FAR struct tcb_s *wtcb = (FAR struct tcb_s *)(uintptr_t)arg;
irqstate_t flags;
/* Disable interrupts to avoid race conditions */
flags = enter_critical_section();
/* It is also possible that an interrupt/context switch beat us to the
* punch and already changed the task's state.
*/
if (wtcb->task_state == TSTATE_WAIT_SEM)
{
/* Cancel the semaphore wait */
nxsem_wait_irq(wtcb, ETIMEDOUT);
}
/* Interrupts may now be enabled. */
leave_critical_section(flags);
}