/****************************************************************************
* sched/sched_garbage.c
*
* Copyright (C) 2009, 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 <nuttx/kmalloc.h>
#include "os_internal.h"
/****************************************************************************
* Pre-processor Definitions
****************************************************************************/
/****************************************************************************
* Private Type Declarations
****************************************************************************/
/****************************************************************************
* Public Variables
****************************************************************************/
/****************************************************************************
* Private Variables
****************************************************************************/
/****************************************************************************
* Private Functions
****************************************************************************/
/****************************************************************************
* Name: sched_kucleanup
*
* Description:
* Clean-up deferred de-allocations of user memory
*
* Input parameters:
* None
*
* Returned Value:
* None
*
****************************************************************************/
static inline void sched_kucleanup(void)
{
irqstate_t flags;
FAR void *address;
/* Test if the delayed deallocation queue is empty. No special protection
* is needed because this is an atomic test.
*/
while (g_delayed_kufree.head)
{
/* Remove the first delayed deallocation. This is not atomic and so
* we must disable interrupts around the queue operation.
*/
flags = irqsave();
address = (FAR void*)sq_remfirst((FAR sq_queue_t*)&g_delayed_kufree);
irqrestore(flags);
/* The address should always be non-NULL since that was checked in the
* 'while' condition above.
*/
if (address)
{
/* Return the memory to the user heap */
kufree(address);
}
}
}
/****************************************************************************
* Name: sched_kcleanup
*
* Description:
* Clean-up deferred de-allocations of kernel memory
*
* Input parameters:
* None
*
* Returned Value:
* None
*
****************************************************************************/
#if defined(CONFIG_NUTTX_KERNEL) && defined(CONFIG_MM_KERNEL_HEAP)
static inline void sched_kcleanup(void)
{
irqstate_t flags;
FAR void *address;
/* Test if the delayed deallocation queue is empty. No special protection
* is needed because this is an atomic test.
*/
while (g_delayed_kfree.head)
{
/* Remove the first delayed deallocation. This is not atomic and so
* we must disable interrupts around the queue operation.
*/
flags = irqsave();
address = (FAR void*)sq_remfirst((FAR sq_queue_t*)&g_delayed_kfree);
irqrestore(flags);
/* The address should always be non-NULL since that was checked in the
* 'while' condition above.
*/
if (address)
{
/* Return the memory to the kernel heap */
kfree(address);
}
}
}
#else
# define sched_kcleanup()
#endif
/****************************************************************************
* Public Functions
****************************************************************************/
/****************************************************************************
* Name: sched_garbagecollection
*
* Description:
* Clean-up memory de-allocations that we queued because they could not
* be freed in that execution context (for example, if the memory was freed
* from an interrupt handler).
*
* This logic may be called from the worker thread (see work_thread.c).
* If, however, CONFIG_SCHED_WORKQUEUE is not defined, then this logic will
* be called from the IDLE thread. It is less optimal for the garbage
* collection to be called from the IDLE thread because it runs at a very
* low priority and could cause false memory out conditions.
*
* Input parameters:
* None
*
* Returned Value:
* None
*
****************************************************************************/
void sched_garbagecollection(void)
{
/* Handle deferred deallocations for the kernel heap */
sched_kcleanup();
/* Handle deferred dealloctions for the user heap */
sched_kucleanup();
}
