incubator-nuttx/sched/sched/sched_suspend.c

108 lines
3.7 KiB
C

/****************************************************************************
* sched/sched/sched_suspend.c
*
* Copyright (C) 2018 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 <assert.h>
#include <nuttx/irq.h>
#include <nuttx/sched.h>
#include <nuttx/arch.h>
#include "sched/sched.h"
/****************************************************************************
* Public Functions
****************************************************************************/
/****************************************************************************
* Name: sched_suspend
*
* Description:
* Suspend/pause the specified thread. This is normally calling indirectly
* via group_suspendchildren();
*
****************************************************************************/
void sched_suspend(FAR struct tcb_s *tcb)
{
irqstate_t flags;
DEBUGASSERT(tcb != NULL);
flags = enter_critical_section();
/* Check the current state of the task */
if (tcb->task_state >= FIRST_BLOCKED_STATE &&
tcb->task_state <= LAST_BLOCKED_STATE)
{
/* Remove the TCB from the the blocked task list. */
sched_removeblocked(tcb);
/* Set the errno value to EINTR. The task will be restarted in the
* running or runnable state and will appear to have awakened from
* the block state by a signal.
*/
tcb->pterrno = EINTR;
/* Move the TCB to the g_stoppedtasks list. */
sched_addblocked(tcb, TSTATE_TASK_STOPPED);
}
else
{
/* The task was running or runnable before being stopped. Simply
* block it in the stopped state. If tcb refers to this task, then
* this action will block this task.
* Before doing that make sure this is not the idle task,
* descheduling that isn't going to end well.
*/
DEBUGASSERT(NULL != tcb->flink);
up_block_task(tcb, TSTATE_TASK_STOPPED);
}
leave_critical_section(flags);
}