nuttx/mm/mm_heap/mm_lock.c
Alin Jerpelea 339457dda3 mm: 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>
2024-09-13 08:49:05 +08:00

120 lines
3.6 KiB
C

/****************************************************************************
* mm/mm_heap/mm_lock.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 <unistd.h>
#include <errno.h>
#include <assert.h>
#include <debug.h>
#include <nuttx/arch.h>
#include <nuttx/mm/mm.h>
#include "mm_heap/mm.h"
/****************************************************************************
* Public Functions
****************************************************************************/
/****************************************************************************
* Name: mm_lock
*
* Description:
* Take the MM mutex. This may be called from the OS in certain conditions
* when it is impossible to wait on a mutex:
* 1.The idle process performs the memory corruption check.
* 2.The task/thread free the memory in the exiting process.
*
* Input Parameters:
* heap - heap instance want to take mutex
*
* Returned Value:
* 0 if the lock can be taken, otherwise negative errno.
*
****************************************************************************/
int mm_lock(FAR struct mm_heap_s *heap)
{
#if defined(CONFIG_BUILD_FLAT) || defined(__KERNEL__)
/* Check current environment */
if (up_interrupt_context())
{
# if !defined(CONFIG_SMP)
/* Check the mutex value, if held by someone, then return false.
* Or, touch the heap internal data directly.
*/
return nxmutex_is_locked(&heap->mm_lock) ? -EAGAIN : 0;
# else
/* Can't take mutex in SMP interrupt handler */
return -EAGAIN;
# endif
}
#endif
/* _SCHED_GETTID() returns the task ID of the task at the head of the
* ready-to-run task list. mm_lock() may be called during context
* switches. There are certain situations during context switching when
* the OS data structures are in flux and then can't be freed immediately
* (e.g. the running thread stack).
*
* This is handled by _SCHED_GETTID() to return the special value -ESRCH
* to indicate this special situation.
*/
if (_SCHED_GETTID() < 0)
{
return -ESRCH;
}
else
{
return nxmutex_lock(&heap->mm_lock);
}
}
/****************************************************************************
* Name: mm_unlock
*
* Description:
* Release the MM mutex when it is not longer needed.
*
****************************************************************************/
void mm_unlock(FAR struct mm_heap_s *heap)
{
#if defined(CONFIG_BUILD_FLAT) || defined(__KERNEL__)
if (up_interrupt_context())
{
return;
}
#endif
DEBUGVERIFY(nxmutex_unlock(&heap->mm_lock));
}