UnixPlatformMemory.h

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// Copyright Epic Games, Inc. All Rights Reserved.
 
/*=============================================================================================
    UnixPlatformMemory.h: Unix platform memory functions
==============================================================================================*/
 
#pragma once
 
#include "CoreTypes.h"
#include "GenericPlatform/GenericPlatformMemory.h"
#include "HAL/PlatformCrt.h"
 
#include <malloc.h>
 
class FString;
 
#ifndef COMPILE_FORK_PAGE_PROTECTOR
    #define COMPILE_FORK_PAGE_PROTECTOR 0
#endif
 
struct FPlatformMemoryStats : public FGenericPlatformMemoryStats
{};
 
struct FExtendedPlatformMemoryStats
{
    SIZE_T Shared_Clean;
 
    SIZE_T Shared_Dirty;
 
    SIZE_T Private_Clean;
 
    SIZE_T Private_Dirty;
 
    SIZE_T KSM_Process_Profit;
 
    bool bIs_KSM_Enabled;
};
 
struct FUnixPlatformMemory : public FGenericPlatformMemory
{
    struct FUnixSharedMemoryRegion : public FSharedMemoryRegion
    {
        int GetFileDescriptor() const { return Fd; }
 
        bool NeedsToUnlinkRegion() const { return bCreatedThisRegion; }
 
        FUnixSharedMemoryRegion(const FString& InName, uint32 InAccessMode, void* InAddress, SIZE_T InSize, int InFd, bool bInCreatedThisRegion)
            :   FSharedMemoryRegion(InName, InAccessMode, InAddress, InSize)
            ,   Fd(InFd)
            ,   bCreatedThisRegion(bInCreatedThisRegion)
        {}
 
    protected:
 
        int             Fd;
 
        bool            bCreatedThisRegion;
    };
 
    //~ Begin FGenericPlatformMemory Interface
    static CORE_API void Init();
    static CORE_API class FMalloc* BaseAllocator();
    static CORE_API FPlatformMemoryStats GetStats();
    static CORE_API FExtendedPlatformMemoryStats GetExtendedStats();
    static CORE_API const FPlatformMemoryConstants& GetConstants();
    static CORE_API bool PageProtect(void* const Ptr, const SIZE_T Size, const bool bCanRead, const bool bCanWrite);
    static CORE_API void* BinnedAllocFromOS(SIZE_T Size);
    static CORE_API void BinnedFreeToOS(void* Ptr, SIZE_T Size);
 
    static CORE_API bool GetForkedPageAllocationInfo(TArray<FForkedPageAllocation>& OutPageAllocationInfos);
 
    class FPlatformVirtualMemoryBlock : public FBasicVirtualMemoryBlock
    {
    public:
 
        FPlatformVirtualMemoryBlock()
        {
        }
 
        FPlatformVirtualMemoryBlock(void *InPtr, uint32 InVMSizeDivVirtualSizeAlignment)
            : FBasicVirtualMemoryBlock(InPtr, InVMSizeDivVirtualSizeAlignment)
        {
        }
        FPlatformVirtualMemoryBlock(const FPlatformVirtualMemoryBlock& Other) = default;
        FPlatformVirtualMemoryBlock& operator=(const FPlatformVirtualMemoryBlock& Other) = default;
 
        CORE_API void Commit(size_t InOffset, size_t InSize);
        CORE_API void Decommit(size_t InOffset, size_t InSize);
        CORE_API void FreeVirtual();
 
        UE_FORCEINLINE_HINT void CommitByPtr(void *InPtr, size_t InSize)
        {
            Commit(size_t(((uint8*)InPtr) - ((uint8*)Ptr)), InSize);
        }
 
        UE_FORCEINLINE_HINT void DecommitByPtr(void *InPtr, size_t InSize)
        {
            Decommit(size_t(((uint8*)InPtr) - ((uint8*)Ptr)), InSize);
        }
 
        UE_FORCEINLINE_HINT void Commit()
        {
            Commit(0, GetActualSize());
        }
 
        UE_FORCEINLINE_HINT void Decommit()
        {
            Decommit(0, GetActualSize());
        }
 
        UE_FORCEINLINE_HINT size_t GetActualSize() const
        {
            return VMSizeDivVirtualSizeAlignment * GetVirtualSizeAlignment();
        }
 
        static CORE_API FPlatformVirtualMemoryBlock AllocateVirtual(size_t Size, size_t InAlignment = FPlatformVirtualMemoryBlock::GetVirtualSizeAlignment());
        static CORE_API size_t GetCommitAlignment();
        static CORE_API size_t GetVirtualSizeAlignment();
    };
 
    static CORE_API FSharedMemoryRegion * MapNamedSharedMemoryRegion(const FString& InName, bool bCreate, uint32 AccessMode, SIZE_T Size);
    static CORE_API bool UnmapNamedSharedMemoryRegion(FSharedMemoryRegion * MemoryRegion);
    static CORE_API bool GetLLMAllocFunctions(void*(*&OutAllocFunction)(size_t), void(*&OutFreeFunction)(void*, size_t), int32& OutAlignment);
    [[noreturn]] static CORE_API void OnOutOfMemory(uint64 Size, uint32 Alignment);
    //~ End FGenericPlatformMemory Interface
 
    static CORE_API bool HasForkPageProtectorEnabled();
 
    static CORE_API bool CanOverallocateVirtualMemory();
};
 
typedef FUnixPlatformMemory FPlatformMemory;