nuttx/sched/semaphore/sem_waitirq.c
Alin Jerpelea eb9030c891 sched: migrate to SPDX identifier
Most tools used for compliance and SBOM generation use SPDX identifiers
This change brings us a step closer to an easy SBOM generation.

Signed-off-by: Alin Jerpelea <alin.jerpelea@sony.com>
2024-09-12 01:10:14 +08:00

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);
}
}