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"
 
#include <config.h>
#if THREADS
#include "pedigree/kernel/process/ConditionVariable.h"
#include "pedigree/kernel/process/Mutex.h"
#endif
#include "pedigree/kernel/process/MemoryPressureManager.h"
#include "pedigree/kernel/process/TerminationDeferral.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 char* 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();
 
#if HOSTED && PEDIGREE_HOSTED_SMOKE_TESTS
  void acquireHostedOperationLock();
  void releaseHostedOperationLock();
  void acquireHostedMappingLock();
  void releaseHostedMappingLock();
  size_t getHostedActiveOperationCount();
#endif
 
 private:
#if THREADS
  ConditionVariable m_Condition;
  ConditionVariable m_DrainCondition;
  Mutex m_Lock;
  Mutex m_MappingLock;
#endif
 
  class ActiveOperation {
   public:
    explicit ActiveOperation(MemoryPool& pool);
    ~ActiveOperation();
 
    explicit operator bool() const {
      return m_Pool != nullptr;
    }
 
   private:
    ActiveOperation(const ActiveOperation&) = delete;
    ActiveOperation& operator=(const ActiveOperation&) = delete;
 
    TerminationDeferral m_TerminationDeferral;
    MemoryPool* m_Pool;
  };
 
  bool beginOperation();
  void endOperation();
 
  size_t m_BufferSize;
 
  size_t m_BufferCount;
 
#ifndef STANDALONE_MEMPOOL
  MemoryRegion m_Pool;
#endif
 
  bool m_bInitialised;
 
  bool m_bClosing;
 
  size_t m_ActiveOperations;
 
  ExtensibleBitmap m_AllocBitmap;
 
#ifndef STANDALONE_MEMPOOL
  MemoryPoolPressureHandler m_PressureHandler;
#endif
 
  uintptr_t allocateDoer(bool canBlock);
};
 
#endif