Ipc::Mem::PageStack Class Reference

#include <PageStack.h>

Collaboration diagram for Ipc::Mem::PageStack:

Classes
class	Config
	PageStack construction and SharedMemorySize calculation parameters. More...

Public Types
typedef std::atomic< size_t >	Levels_t
typedef unsigned int	PageCount
	the number of (free and/or used) pages in a stack More...

Public Member Functions
	PageStack (const Config &)
PageCount	capacity () const
size_t	pageSize () const
PageCount	size () const
	an approximate number of free pages More...
bool	pop (PageId &page)
	sets value and returns true unless no free page numbers are found More...
void	push (PageId &page)
	makes value available as a free page number to future pop() callers More...
bool	pageIdIsValid (const PageId &page) const
size_t	sharedMemorySize () const
size_t	stackSize () const
size_t	levelsPaddingSize () const

Static Public Member Functions
static size_t	SharedMemorySize (const Config &)
	total shared memory size required to share More...
static size_t	StackSize (const PageCount capacity)
static size_t	LevelsPaddingSize (const PageCount capacity)
static PoolId	IdForMemStoreSpace ()
	stack of free cache_mem slot positions More...
static PoolId	IdForMultipurposePool ()
	multipurpose PagePool of shared memory pages More...
static PoolId	IdForSwapDirSpace (const int dirIdx)
	stack of free rock cache_dir slot numbers More...

Private Attributes
const Config	config_
std::atomic< PageCount >	size_
	a lower bound for the number of free pages (for debugging purposes) More...
IdSet	ids_
	free pages (valid with positive capacity_) More...

Detailed Description

Atomic container of "free" PageIds. Detects (some) double-free bugs. Assumptions: All page numbers are unique, positive, with a known maximum. A pushed page may not become available immediately but is never truly lost.

Definition at line 108 of file PageStack.h.

Member Typedef Documentation

Levels_t

typedef std::atomic<size_t> Ipc::Mem::PageStack::Levels_t

Definition at line 111 of file PageStack.h.

PageCount

typedef unsigned int Ipc::Mem::PageStack::PageCount

Definition at line 117 of file PageStack.h.

Constructor & Destructor Documentation

PageStack()

Ipc::Mem::PageStack::PageStack ( const Config &  config )

explicit

Definition at line 430 of file PageStack.cc.

References Ipc::Mem::PageStack::Config::capacity, config_, Ipc::Mem::PageStack::Config::createFull, ids_, Ipc::Mem::IdSet::makeFullBeforeSharing(), and size_.

Member Function Documentation

capacity()

PageCount Ipc::Mem::PageStack::capacity ( ) const

inline

Definition at line 135 of file PageStack.h.

References Ipc::Mem::PageStack::Config::capacity, and config_.

IdForMemStoreSpace()

static PoolId Ipc::Mem::PageStack::IdForMemStoreSpace ( )

inlinestatic

The following functions return PageStack IDs for the corresponding PagePool or a similar PageStack user. The exact values are unimportant, but their uniqueness and stability eases debugging.

Definition at line 167 of file PageStack.h.

Referenced by MemStoreRr::create(), and MemStore::noteFreeMapSlice().

IdForMultipurposePool()

static PoolId Ipc::Mem::PageStack::IdForMultipurposePool ( )

inlinestatic

Definition at line 169 of file PageStack.h.

Referenced by SharedMemPagesRr::create().

IdForSwapDirSpace()

static PoolId Ipc::Mem::PageStack::IdForSwapDirSpace ( const int  dirIdx )

inlinestatic

Definition at line 171 of file PageStack.h.

Referenced by Rock::SwapDirRr::create(), Rock::Rebuild::freeSlot(), and Rock::SwapDir::noteFreeMapSlice().

levelsPaddingSize()

size_t Ipc::Mem::PageStack::levelsPaddingSize ( ) const

inline

Definition at line 158 of file PageStack.h.

References Ipc::Mem::PageStack::Config::capacity, config_, and LevelsPaddingSize().

LevelsPaddingSize()

size_t Ipc::Mem::PageStack::LevelsPaddingSize ( const PageCount  capacity )

static

Returns

the number of padding bytes to align PagePool::theLevels array

Definition at line 519 of file PageStack.cc.

Referenced by levelsPaddingSize().

pageIdIsValid()

bool Ipc::Mem::PageStack::pageIdIsValid

(

const PageId &

page

)

const

Definition at line 483 of file PageStack.cc.

References Ipc::Mem::PageId::number, and Ipc::Mem::PageId::pool.

pageSize()

size_t Ipc::Mem::PageStack::pageSize ( ) const

inline

Definition at line 136 of file PageStack.h.

References config_, and Ipc::Mem::PageStack::Config::pageSize.

pop()

bool Ipc::Mem::PageStack::pop

(

PageId &

page

)

Definition at line 442 of file PageStack.cc.

References assert, debugs, Ipc::Mem::PageId::number, and Ipc::Mem::PageId::pool.

Referenced by MemStore::reserveSapForWriting().

push()

void Ipc::Mem::PageStack::push

(

PageId &

page

)

Definition at line 465 of file PageStack.cc.

References assert, debugs, and Ipc::Mem::PageId::number.

Referenced by MemStore::noteFreeMapSlice(), and MemStore::reserveSapForWriting().

sharedMemorySize()

size_t Ipc::Mem::PageStack::sharedMemorySize

(

)

const

Definition at line 490 of file PageStack.cc.

SharedMemorySize()

size_t Ipc::Mem::PageStack::SharedMemorySize ( const Config &  cfg )

static

Definition at line 496 of file PageStack.cc.

References Ipc::Mem::PageStack::Config::capacity, Ipc::Mem::PageId::maxPurpose, and Ipc::Mem::PageStack::Config::pageSize.

size()

PageCount Ipc::Mem::PageStack::size ( ) const

inline

Definition at line 138 of file PageStack.h.

References size_.

stackSize()

size_t Ipc::Mem::PageStack::stackSize

(

)

const

Definition at line 513 of file PageStack.cc.

StackSize()

size_t Ipc::Mem::PageStack::StackSize ( const PageCount  capacity )

static

shared memory size required only by PageStack, excluding shared counters and page data

Definition at line 504 of file PageStack.cc.

References Ipc::Mem::IdSet::MemorySize().

Member Data Documentation

config_

const Config Ipc::Mem::PageStack::config_

private

Definition at line 174 of file PageStack.h.

Referenced by PageStack(), capacity(), levelsPaddingSize(), and pageSize().

ids_

IdSet Ipc::Mem::PageStack::ids_

private

Definition at line 178 of file PageStack.h.

Referenced by PageStack().

size_

std::atomic<PageCount> Ipc::Mem::PageStack::size_

private

Definition at line 176 of file PageStack.h.

Referenced by PageStack(), and size().

---

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

• src/ipc/mem/PageStack.h
• src/ipc/mem/PageStack.cc