MemoryPool.h

/*
 * Copyright (c) 2008-2014, Pedigree Developers
 *
 * Please see the CONTRIB file in the root of the source tree for a full
 * list of contributors.
 *
 * Permission to use, copy, modify, and distribute this software for any
 * purpose with or without fee is hereby granted, provided that the above
 * copyright notice and this permission notice appear in all copies.
 *
 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
 * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
 */

#ifndef _UTILITY_MEMORY_POOL
#define _UTILITY_MEMORY_POOL

#include "pedigree/kernel/compiler.h"
#include "pedigree/kernel/processor/types.h"
#ifdef THREADS
#include "pedigree/kernel/process/ConditionVariable.h"
#include "pedigree/kernel/process/Mutex.h"
#endif
#include "pedigree/kernel/process/MemoryPressureManager.h"
#include "pedigree/kernel/processor/MemoryRegion.h"
#include "pedigree/kernel/utilities/ExtensibleBitmap.h"
#include "pedigree/kernel/utilities/String.h"

class MemoryPool;

class MemoryPoolPressureHandler : public MemoryPressureHandler
{
  public:
    MemoryPoolPressureHandler(MemoryPool *pool);
    virtual ~MemoryPoolPressureHandler();

    virtual const String getMemoryPressureDescription();

    virtual bool compact();

  private:
    MemoryPool *m_Pool;
};

class EXPORTED_PUBLIC MemoryPool
{
  public:
    MemoryPool();
    MemoryPool(const char *poolName);
    virtual ~MemoryPool();

    bool initialise(size_t poolSize, size_t bufferSize = 1024);

    inline bool initialised()
    {
        return m_bInitialised;
    }

    uintptr_t allocate();

    uintptr_t allocateNow();

    void free(uintptr_t buffer);

    bool trim();

  private:
#ifdef THREADS
    ConditionVariable m_Condition;
    Mutex m_Lock;
#endif

    size_t m_BufferSize;

    size_t m_BufferCount;

#ifndef STANDALONE_MEMPOOL
    MemoryRegion m_Pool;
#endif

    bool m_bInitialised;

    ExtensibleBitmap m_AllocBitmap;

#ifndef STANDALONE_MEMPOOL
    MemoryPoolPressureHandler m_PressureHandler;
#endif

    uintptr_t allocateDoer(bool canBlock);
};

#endif