/*****************************************************************************
* sched/group_leave.c
*
* Copyright (C) 2013 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,
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*
*****************************************************************************/
/*****************************************************************************
* Included Files
*****************************************************************************/
#include <nuttx/config.h>
#include <sched.h>
#include <assert.h>
#include <errno.h>
#include <debug.h>
#include "os_internal.h"
#ifdef HAVE_TASK_GROUP
/*****************************************************************************
* Pre-processor Definitions
*****************************************************************************/
/*****************************************************************************
* Private Types
*****************************************************************************/
/*****************************************************************************
* Private Data
*****************************************************************************/
/*****************************************************************************
* Private Functions
*****************************************************************************/
/*****************************************************************************
* Public Functions
*****************************************************************************/
/*****************************************************************************
* Name: group_leave
*
* Description:
* Release a reference on a group. This function is called when a task or
* thread exits. It decrements the reference count on the group. If the
* reference count decrements to zero, then it frees the group and all of
* resources contained in the group.
*
* Parameters:
* tcb - The TCB of the task that is exiting.
*
* Return Value:
* None.
*
* Assumptions:
* Called during task deletion in a safe context. No special precautions
* are required here.
*
*****************************************************************************/
void group_leave(FAR _TCB *tcb)
{
FAR struct task_group_s *group;
DEBUGASSERT(tcb);
/* Make sure that we have a group */
group = tcb->group;
if (group)
{
/* Would the reference count decrement to zero? */
if (group->tg_crefs > 1)
{
/* No.. just decrement the reference count and return */
group->tg_crefs--;
}
else
{
/* Yes.. Release all of the resource contained within the group */
/* Free all un-reaped child exit status */
task_removechildren(tcb);
/* Release the group container itself */
sched_free(group);
}
tcb->group = NULL;
}
}
#endif /* HAVE_TASK_GROUP */
