#include <GenericPlatformMallocCrash.h>

Inheritance diagram for FGenericPlatformMallocCrash:

Public Types
enum	{ LARGE_MEMORYPOOL_SIZE = 2 * 1024 * 1024 , REQUIRED_ALIGNMENT = 16 , NUM_POOLS = 14 , MAX_NUM_ALLOCS_IN_POOL = 2048 , MEM_TAG = 0xfe , MEM_WIPETAG = 0xcd }

Public Member Functions
	FGenericPlatformMallocCrash (FMalloc *MainMalloc)

virtual	~FGenericPlatformMallocCrash ()

void	SetAsGMalloc ()

virtual void *	Malloc (SIZE_T Size, uint32 Alignment) override

virtual void *	Realloc (void *Ptr, SIZE_T NewSize, uint32 Alignment) override

virtual void	Free (void *) override

virtual bool	GetAllocationSize (void *Original, SIZE_T &SizeOut) override

virtual bool	IsInternallyThreadSafe () const override

virtual bool	ValidateHeap () override

virtual const TCHAR *	GetDescriptiveName () override

CORE_API void	PrintPoolsUsage ()

Public Member Functions inherited from FMalloc
virtual CORE_API void *	TryMalloc (SIZE_T Count, uint32 Alignment=DEFAULT_ALIGNMENT)

virtual CORE_API void *	TryRealloc (void *Original, SIZE_T Count, uint32 Alignment=DEFAULT_ALIGNMENT)

virtual CORE_API void *	MallocZeroed (SIZE_T Count, uint32 Alignment=DEFAULT_ALIGNMENT)

virtual CORE_API void *	TryMallocZeroed (SIZE_T Count, uint32 Alignment=DEFAULT_ALIGNMENT)

virtual SIZE_T	QuantizeSize (SIZE_T Count, uint32 Alignment)

virtual void	Trim (bool bTrimThreadCaches)

virtual void	SetupTLSCachesOnCurrentThread ()

virtual void	MarkTLSCachesAsUsedOnCurrentThread ()

virtual void	MarkTLSCachesAsUnusedOnCurrentThread ()

virtual void	ClearAndDisableTLSCachesOnCurrentThread ()

virtual CORE_API void	InitializeStatsMetadata ()

virtual CORE_API void	UpdateStats ()

virtual CORE_API void	GetAllocatorStats (FGenericMemoryStats &out_Stats)

virtual void	DumpAllocatorStats (class FOutputDevice &Ar)

virtual void	OnMallocInitialized ()

virtual void	OnPreFork ()

virtual void	OnPostFork ()

virtual uint64	GetImmediatelyFreeableCachedMemorySize () const

virtual uint64	GetTotalFreeCachedMemorySize () const

Public Member Functions inherited from FUseSystemMallocForNew
CORE_API void *	operator new (size_t Size)

CORE_API void	operator delete (void *Ptr)

void *	operator new[] (size_t Size)

void	operator delete[] (void *Ptr)

Public Member Functions inherited from FExec
virtual CORE_API	~FExec ()

virtual CORE_API bool	Exec (UWorld InWorld, const TCHAR Cmd, FOutputDevice &Ar)

Static Public Member Functions
static CORE_API FGenericPlatformMallocCrash &	Get (FMalloc *MainMalloc=nullptr)

static bool	IsActive ()

Protected Member Functions
bool	CheckThreadForAllocation () const

bool	CheckThreadForFree () const

bool	IsPtrInLargePool (void *Ptr) const

bool	IsPtrInSmallPool (void *Ptr) const

const FPoolDesc &	GetPoolDesc (uint32 Index) const

uint32	CalculateSmallPoolTotalSize () const

uint32	CalculateBookkeepingPoolTotalSize () const

void	InitializeSmallPools ()

FMallocCrashPool *	ChoosePoolForSize (uint32 AllocationSize) const

FMallocCrashPool *	FindPoolForAlloc (void *Ptr) const

uint8 *	AllocateFromBookkeeping (uint32 AllocationSize)

uint8 *	AllocateFromSmallPool (uint32 AllocationSize)

uint64	GetAllocationSize (void *Original)

Protected Member Functions inherited from FExec
virtual bool	Exec_Runtime (UWorld InWorld, const TCHAR Cmd, FOutputDevice &Ar)

virtual bool	Exec_Dev (UWorld InWorld, const TCHAR Cmd, FOutputDevice &Ar)

virtual bool	Exec_Editor (UWorld InWorld, const TCHAR Cmd, FOutputDevice &Ar)

Static Protected Member Functions
static uint32	SafePageSize ()

Protected Attributes
FCriticalSection	InternalLock

int32	CrashedThreadId = 0

uint8 *	LargeMemoryPool = nullptr

uint32	LargeMemoryPoolOffset = 0

uint8 *	SmallMemoryPool = nullptr

uint32	SmallMemoryPoolOffset = 0

uint32	SmallMemoryPoolSize = 0

uint8 *	BookkeepingPool = nullptr

uint32	BookkeepingPoolOffset = 0

uint32	BookkeepingPoolSize = 0

FMalloc *	PreviousMalloc = nullptr

Friends
struct	FPoolDesc

struct	FMallocCrashPool

Additional Inherited Members
Static Public Attributes inherited from FMalloc
static CORE_API TAtomic< uint64 >	MaxSingleAlloc

Detailed Description

Simple pooled memory allocator that uses preallocated memory. Instance of this class replaces GMalloc after a crash, so we can use dynamic memory allocation even if the app crashes due to OOM.

Member Enumeration Documentation

◆ anonymous enum

anonymous enum

Enumerator
LARGE_MEMORYPOOL_SIZE
REQUIRED_ALIGNMENT
NUM_POOLS
MAX_NUM_ALLOCS_IN_POOL
MEM_TAG
MEM_WIPETAG

Constructor & Destructor Documentation

◆ FGenericPlatformMallocCrash()

FGenericPlatformMallocCrash::FGenericPlatformMallocCrash ( FMalloc * MainMalloc )

◆ ~FGenericPlatformMallocCrash()

FGenericPlatformMallocCrash::~FGenericPlatformMallocCrash ( )

virtual

Member Function Documentation

◆ AllocateFromBookkeeping()

uint8 * FGenericPlatformMallocCrash::AllocateFromBookkeeping ( uint32 AllocationSize )

protected

◆ AllocateFromSmallPool()

uint8 * FGenericPlatformMallocCrash::AllocateFromSmallPool ( uint32 AllocationSize )

protected

◆ CalculateBookkeepingPoolTotalSize()

uint32 FGenericPlatformMallocCrash::CalculateBookkeepingPoolTotalSize ( ) const

protected

◆ CalculateSmallPoolTotalSize()

uint32 FGenericPlatformMallocCrash::CalculateSmallPoolTotalSize ( ) const

protected

◆ CheckThreadForAllocation()

PRAGMA_DISABLE_UNREACHABLE_CODE_WARNINGS bool FGenericPlatformMallocCrash::CheckThreadForAllocation ( ) const

protected

Whether it is safe to call crash malloc's methods.

◆ CheckThreadForFree()

bool FGenericPlatformMallocCrash::CheckThreadForFree ( ) const

protected

◆ ChoosePoolForSize()

FMallocCrashPool * FGenericPlatformMallocCrash::ChoosePoolForSize ( uint32 AllocationSize ) const

protected

◆ FindPoolForAlloc()

FMallocCrashPool * FGenericPlatformMallocCrash::FindPoolForAlloc ( void * Ptr ) const

protected

◆ Free()

void FGenericPlatformMallocCrash::Free ( void * Original )

overridevirtual

Free

Implements FMalloc.

◆ Get()

FGenericPlatformMallocCrash & FGenericPlatformMallocCrash::Get ( FMalloc * MainMalloc = nullptr )

static

Creates a new instance.

◆ GetAllocationSize() [1/2]

uint64 FGenericPlatformMallocCrash::GetAllocationSize ( void * Original )

protected

◆ GetAllocationSize() [2/2]

bool FGenericPlatformMallocCrash::GetAllocationSize	(	void *	Original,
		SIZE_T &	SizeOut
	)

overridevirtual

If possible determine the size of the memory allocated at the given address

Parameters

Original	- Pointer to memory we are checking the size of
SizeOut	- If possible, this value is set to the size of the passed in pointer

Returns: true if succeeded

Reimplemented from FMalloc.

◆ GetDescriptiveName()

virtual const TCHAR * FGenericPlatformMallocCrash::GetDescriptiveName ( )

inlineoverridevirtual

Gets descriptive name for logging purposes.

Returns: pointer to human-readable malloc name

Reimplemented from FMalloc.

◆ GetPoolDesc()

const FPoolDesc & FGenericPlatformMallocCrash::GetPoolDesc ( uint32 Index ) const

protected

Generated by the FGenericPlatformMallocCrash::PrintPoolsUsage.

◆ InitializeSmallPools()

void FGenericPlatformMallocCrash::InitializeSmallPools ( )

protected

◆ IsActive()

bool FGenericPlatformMallocCrash::IsActive ( )

static

◆ IsInternallyThreadSafe()

virtual bool FGenericPlatformMallocCrash::IsInternallyThreadSafe ( ) const

inlineoverridevirtual

Returns if the allocator is guaranteed to be thread-safe and therefore doesn't need a unnecessary thread-safety wrapper around it.

Reimplemented from FMalloc.

◆ IsPtrInLargePool()

PRAGMA_RESTORE_UNREACHABLE_CODE_WARNINGS bool FGenericPlatformMallocCrash::IsPtrInLargePool ( void * Ptr ) const

protected

◆ IsPtrInSmallPool()

bool FGenericPlatformMallocCrash::IsPtrInSmallPool ( void * Ptr ) const

protected

◆ Malloc()

void * FGenericPlatformMallocCrash::Malloc	(	SIZE_T	Count,
		uint32	Alignment
	)

overridevirtual

Malloc

Implements FMalloc.

◆ PrintPoolsUsage()

void FGenericPlatformMallocCrash::PrintPoolsUsage ( )

◆ Realloc()

void * FGenericPlatformMallocCrash::Realloc	(	void *	Original,
		SIZE_T	Count,
		uint32	Alignment
	)

overridevirtual

Realloc

Implements FMalloc.

◆ SafePageSize()

uint32 FGenericPlatformMallocCrash::SafePageSize ( )

staticprotected

Returns: page size, if page size is not initialized, returns 64k.

◆ SetAsGMalloc()

void FGenericPlatformMallocCrash::SetAsGMalloc ( )

Sets as GMalloc. This method locks to the thread that crashed. Any next calls to this method or GMalloc from other threads will dead-lock those threads, but this is ok, because we are shutting down. This also fixes a lot of potential issues of using dynamic allocation during crash dumping.

Warning: This is not super safe, may interfere with other allocations, ie. replacing vtable during running the code from the previous malloc will probably crash other threads.

◆ ValidateHeap()

virtual bool FGenericPlatformMallocCrash::ValidateHeap ( )

inlineoverridevirtual

Validates the allocator's heap

Reimplemented from FMalloc.

Friends And Related Symbol Documentation

◆ FMallocCrashPool

friend struct FMallocCrashPool

friend

◆ FPoolDesc

friend struct FPoolDesc

friend

Member Data Documentation

◆ BookkeepingPool

uint8* FGenericPlatformMallocCrash::BookkeepingPool = nullptr

protected

Preallocated memory pool for bookkeeping.

◆ BookkeepingPoolOffset

uint32 FGenericPlatformMallocCrash::BookkeepingPoolOffset = 0

protected

Current position in the bookkeeping pool.

◆ BookkeepingPoolSize

uint32 FGenericPlatformMallocCrash::BookkeepingPoolSize = 0

protected

◆ CrashedThreadId

int32 FGenericPlatformMallocCrash::CrashedThreadId = 0

protected

The id of the thread that crashed.

◆ InternalLock

FCriticalSection FGenericPlatformMallocCrash::InternalLock

protected

Used to lock crash malloc to one thread.

◆ LargeMemoryPool

uint8* FGenericPlatformMallocCrash::LargeMemoryPool = nullptr

protected

Preallocated memory pool for large allocations.

◆ LargeMemoryPoolOffset

uint32 FGenericPlatformMallocCrash::LargeMemoryPoolOffset = 0

protected

Current position in the large memory pool.

◆ PreviousMalloc

FMalloc* FGenericPlatformMallocCrash::PreviousMalloc = nullptr

protected

Previously used malloc.

◆ SmallMemoryPool

uint8* FGenericPlatformMallocCrash::SmallMemoryPool = nullptr

protected

Preallocated memory pool for small allocations.

◆ SmallMemoryPoolOffset

uint32 FGenericPlatformMallocCrash::SmallMemoryPoolOffset = 0

protected

Current position in the small memory pool.

◆ SmallMemoryPoolSize

uint32 FGenericPlatformMallocCrash::SmallMemoryPoolSize = 0

protected

The documentation for this struct was generated from the following files:

Engine/Source/Runtime/Core/Public/GenericPlatform/GenericPlatformMallocCrash.h
Engine/Source/Runtime/Core/Private/GenericPlatform/GenericPlatformMallocCrash.cpp

Public Types

Public Member Functions

Static Public Member Functions

Protected Member Functions

Static Protected Member Functions

Protected Attributes

Friends

Additional Inherited Members

Detailed Description

Member Enumeration Documentation

◆ anonymous enum

Constructor & Destructor Documentation

◆ FGenericPlatformMallocCrash()

◆ ~FGenericPlatformMallocCrash()

Member Function Documentation

◆ AllocateFromBookkeeping()

◆ AllocateFromSmallPool()

◆ CalculateBookkeepingPoolTotalSize()

◆ CalculateSmallPoolTotalSize()

◆ CheckThreadForAllocation()

◆ CheckThreadForFree()

◆ ChoosePoolForSize()

◆ FindPoolForAlloc()

◆ Free()

◆ Get()

◆ GetAllocationSize() [1/2]

◆ GetAllocationSize() [2/2]

◆ GetDescriptiveName()

◆ GetPoolDesc()

◆ InitializeSmallPools()

◆ IsActive()

◆ IsInternallyThreadSafe()

◆ IsPtrInLargePool()

◆ IsPtrInSmallPool()

◆ Malloc()

◆ PrintPoolsUsage()

◆ Realloc()

◆ SafePageSize()

◆ SetAsGMalloc()

◆ ValidateHeap()

Friends And Related Symbol Documentation

◆ FMallocCrashPool

◆ FPoolDesc

Member Data Documentation

◆ BookkeepingPool

◆ BookkeepingPoolOffset

◆ BookkeepingPoolSize

◆ CrashedThreadId

◆ InternalLock

◆ LargeMemoryPool

◆ LargeMemoryPoolOffset

◆ PreviousMalloc

◆ SmallMemoryPool

◆ SmallMemoryPoolOffset

◆ SmallMemoryPoolSize