MemCache Class Reference

A cache for physical memory indexed by page number. More...

#include <memcache.h>

Inheritance diagram for MemCache:

Classes
struct	Buffers
	Cache MMIO registers and pending writes to them. More...
struct	CacheEntry

Public Types
enum	Type {   TYPE_R = 1u << 0, TYPE_W = 1u << 1, TYPE_RMW = TYPE_R | TYPE_W, TYPE_U = 1u << 2,   TYPE_RES = 1u << 3, TYPE_X = 1u << 4 }

Public Member Functions
CacheEntry *	get (unsigned long phys1, unsigned long phys2, unsigned len, Type type)
	Get an entry from the cache or fetch one from memory.
void	invalidate (bool writeback)
	Invalidate the cache, thus writeback the buffers.
	MemCache (DBus< MessageMem > &mem, DBus< MessageMemRegion > &memregion)

Public Attributes
bool	debug
CacheEntry	_values [ASSOZ]
unsigned	_newest

Protected Attributes
DBus< MessageMem > &	_mem
DBus< MessageMemRegion > &	_memregion
unsigned	_fault
unsigned	_error_code
unsigned	_debug_fault_line
unsigned	_mtr_in
unsigned	_mtr_read
unsigned	_mtr_out

Private Types
enum	{ SIZE = 64, ASSOZ = 6, BUFFERS = 6, BUFFER_SIZE = 16 + 4 }

Private Member Functions
unsigned	slot (unsigned phys)
void	buffer_io (bool read, unsigned index)
void	invalidate_dirty ()
	Invalidate the oldest dirty entry in the list.

Private Attributes
struct {
CacheEntry   _values [ASSOZ]
unsigned   _newest
}	_sets [SIZE]
MemCache::Buffers	_buffers [BUFFERS]
unsigned	_newest_buffer
unsigned	_oldest_write
unsigned	_newest_write

Detailed Description

A cache for physical memory indexed by page number.

Member Enumeration Documentation

anonymous enum

private

Enumerator:

SIZE
ASSOZ
BUFFERS
BUFFER_SIZE

enum MemCache::Type

Enumerator:

TYPE_R
TYPE_W
TYPE_RMW
TYPE_U
TYPE_RES
TYPE_X

Constructor & Destructor Documentation

MemCache::MemCache ( DBus< MessageMem > &  mem, DBus< MessageMemRegion > &  memregion  )

inline

Member Function Documentation

void MemCache::buffer_io ( bool  read, unsigned  index  )

inlineprivate

CacheEntry* MemCache::get ( unsigned long  phys1, unsigned long  phys2, unsigned  len, Type  type  )

inline

Get an entry from the cache or fetch one from memory.

What should we do if two different pages are referenced?

We could fallback to dword mode but there is this strange corner case where somebody does an locked operation crossing two non-adjunct pages, where we have to map the two pages into an 8k region and unmap them later on....

Invalidate a dirty entry, as we entry points to the last used buffer it must be the oldest write.

void MemCache::invalidate ( bool  writeback )

inline

Invalidate the cache, thus writeback the buffers.

void MemCache::invalidate_dirty ( )

inlineprivate

Invalidate the oldest dirty entry in the list.

unsigned MemCache::slot ( unsigned  phys )

inlineprivate

Member Data Documentation

MemCache::Buffers MemCache::_buffers[BUFFERS]

private

unsigned MemCache::_debug_fault_line

protected

unsigned MemCache::_error_code

protected

unsigned MemCache::_fault

protected

DBus<MessageMem>& MemCache::_mem

protected

DBus<MessageMemRegion>& MemCache::_memregion

protected

unsigned MemCache::_mtr_in

protected

unsigned MemCache::_mtr_out

protected

unsigned MemCache::_mtr_read

protected

unsigned MemCache::_newest

unsigned MemCache::_newest_buffer

private

unsigned MemCache::_newest_write

private

unsigned MemCache::_oldest_write

private

struct { ... } MemCache::_sets[SIZE]

CacheEntry MemCache::_values[ASSOZ]

bool MemCache::debug

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

• vancouver/executor/memcache.h