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/****************************************************************************
* arch/x86/src/common/up_releasestack.c
*
* Copyright (C) 2011, 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,
* 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 <sched.h>
#include <debug.h>
#include <nuttx/arch.h>
#include <nuttx/kmalloc.h>
#include "up_internal.h"
/****************************************************************************
* Private Types
****************************************************************************/
/****************************************************************************
* Private Function Prototypes
****************************************************************************/
/****************************************************************************
* Global Functions
****************************************************************************/
/****************************************************************************
* Name: up_release_stack
*
* Description:
* A task has been stopped. Free all stack related resources retained in
* the defunct TCB.
*
* Input Parmeters
* - dtcb: The TCB containing information about the stack to be released
* - ttype: The thread type. This may be one of following (defined in
* include/nuttx/sched.h):
*
* TCB_FLAG_TTYPE_TASK Normal user task
* TCB_FLAG_TTYPE_PTHREAD User pthread
* TCB_FLAG_TTYPE_KERNEL Kernel thread
*
* This thread type is normally available in the flags field of the TCB,
* however, there are certain error recovery contexts where the TCB may
* not be fully initialized when up_release_stack is called.
*
* If CONFIG_BUILD_KERNEL is defined, then this thread type may affect
* how the stack is freed. For example, kernel thread stacks may have
* been allocated from protected kernel memory. Stacks for user tasks
* and threads must have come from memory that is accessible to user
* code.
*
* Returned Value:
* None
*
****************************************************************************/
void up_release_stack(FAR struct tcb_s *dtcb, uint8_t ttype)
{
/* Is there a stack allocated? */
if (dtcb->stack_alloc_ptr)
{
#if defined(CONFIG_BUILD_KERNEL) && defined(CONFIG_MM_KERNEL_HEAP)
/* Use the kernel allocator if this is a kernel thread */
if (ttype == TCB_FLAG_TTYPE_KERNEL)
{
sched_kfree(dtcb->stack_alloc_ptr);
}
else
#endif
{
/* Use the user-space allocator if this is a task or pthread */
sched_ufree(dtcb->stack_alloc_ptr);
}
/* Mark the stack freed */
dtcb->stack_alloc_ptr = NULL;
}
/* The size of the allocated stack is now zero */
dtcb->adj_stack_size = 0;
}
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