gem5  v21.1.0.2
Public Member Functions | Private Member Functions | Private Attributes | List of all members
gem5::memory::PhysicalMemory Class Reference

The physical memory encapsulates all memories in the system and provides basic functionality for accessing those memories without going through the memory system and interconnect. More...

#include <physical.hh>

Inheritance diagram for gem5::memory::PhysicalMemory:
gem5::Serializable

Public Member Functions

 PhysicalMemory (const std::string &_name, const std::vector< AbstractMemory * > &_memories, bool mmap_using_noreserve, const std::string &shared_backstore)
 Create a physical memory object, wrapping a number of memories. More...
 
 ~PhysicalMemory ()
 Unmap all the backing store we have used. More...
 
const std::string name () const
 Return the name for debugging and for creation of sections for checkpointing. More...
 
bool isMemAddr (Addr addr) const
 Check if a physical address is within a range of a memory that is part of the global address map. More...
 
AddrRangeList getConfAddrRanges () const
 Get the memory ranges for all memories that are to be reported to the configuration table. More...
 
uint64_t totalSize () const
 Get the total physical memory size. More...
 
std::vector< BackingStoreEntrygetBackingStore () const
 Get the pointers to the backing store for external host access. More...
 
void access (PacketPtr pkt)
 Perform an untimed memory access and update all the state (e.g. More...
 
void functionalAccess (PacketPtr pkt)
 Perform an untimed memory read or write without changing anything but the memory itself. More...
 
void serialize (CheckpointOut &cp) const override
 Serialize all the memories in the system. More...
 
void serializeStore (CheckpointOut &cp, unsigned int store_id, AddrRange range, uint8_t *pmem) const
 Serialize a specific store. More...
 
void unserialize (CheckpointIn &cp) override
 Unserialize the memories in the system. More...
 
void unserializeStore (CheckpointIn &cp)
 Unserialize a specific backing store, identified by a section. More...
 
- Public Member Functions inherited from gem5::Serializable
 Serializable ()
 
virtual ~Serializable ()
 
void serializeSection (CheckpointOut &cp, const char *name) const
 Serialize an object into a new section. More...
 
void serializeSection (CheckpointOut &cp, const std::string &name) const
 
void unserializeSection (CheckpointIn &cp, const char *name)
 Unserialize an a child object. More...
 
void unserializeSection (CheckpointIn &cp, const std::string &name)
 

Private Member Functions

 PhysicalMemory (const PhysicalMemory &)
 
PhysicalMemoryoperator= (const PhysicalMemory &)
 
void createBackingStore (AddrRange range, const std::vector< AbstractMemory * > &_memories, bool conf_table_reported, bool in_addr_map, bool kvm_map)
 Create the memory region providing the backing store for a given address range that corresponds to a set of memories in the simulated system. More...
 

Private Attributes

std::string _name
 
AddrRangeMap< AbstractMemory *, 1 > addrMap
 
std::vector< AbstractMemory * > memories
 
uint64_t size
 
const bool mmapUsingNoReserve
 
const std::string sharedBackstore
 
std::vector< BackingStoreEntrybackingStore
 

Additional Inherited Members

- Static Public Member Functions inherited from gem5::Serializable
static const std::string & currentSection ()
 Gets the fully-qualified name of the active section. More...
 
static void generateCheckpointOut (const std::string &cpt_dir, std::ofstream &outstream)
 Generate a checkpoint file so that the serialization can be routed to it. More...
 

Detailed Description

The physical memory encapsulates all memories in the system and provides basic functionality for accessing those memories without going through the memory system and interconnect.

The physical memory is also responsible for providing the host system backingstore used by the memories in the simulated guest system. When the system is created, the physical memory allocates the backing store based on the address ranges that are populated in the system, and does so independent of how those map to actual memory controllers. Thus, the physical memory completely abstracts the mapping of the backing store of the host system and the address mapping in the guest system. This enables us to arbitrarily change the number of memory controllers, and their address mapping, as long as the ranges stay the same.

Definition at line 122 of file physical.hh.

Constructor & Destructor Documentation

◆ PhysicalMemory() [1/2]

gem5::memory::PhysicalMemory::PhysicalMemory ( const PhysicalMemory )
private

◆ PhysicalMemory() [2/2]

gem5::memory::PhysicalMemory::PhysicalMemory ( const std::string &  _name,
const std::vector< AbstractMemory * > &  _memories,
bool  mmap_using_noreserve,
const std::string &  shared_backstore 
)

Create a physical memory object, wrapping a number of memories.

Definition at line 77 of file physical.cc.

References addrMap, gem5::ArmISA::c, createBackingStore(), DPRINTF, gem5::ArmISA::f, fatal, fatal_if, gem5::ArmISA::m, memories, gem5::MipsISA::r, size, and warn.

◆ ~PhysicalMemory()

gem5::memory::PhysicalMemory::~PhysicalMemory ( )

Unmap all the backing store we have used.

Definition at line 248 of file physical.cc.

References backingStore, and gem5::ArmISA::s.

Member Function Documentation

◆ access()

void gem5::memory::PhysicalMemory::access ( PacketPtr  pkt)

Perform an untimed memory access and update all the state (e.g.

locked addresses) and statistics accordingly. The packet is turned into a response if required.

Parameters
pktPacket performing the access

Definition at line 298 of file physical.cc.

References addrMap, gem5::Packet::getAddrRange(), gem5::Packet::isRequest(), and gem5::ArmISA::m.

◆ createBackingStore()

void gem5::memory::PhysicalMemory::createBackingStore ( AddrRange  range,
const std::vector< AbstractMemory * > &  _memories,
bool  conf_table_reported,
bool  in_addr_map,
bool  kvm_map 
)
private

Create the memory region providing the backing store for a given address range that corresponds to a set of memories in the simulated system.

Parameters
rangeThe address range covered
memoriesThe memories this range maps to
kvm_mapShould KVM map this memory for the guest

Definition at line 190 of file physical.cc.

References backingStore, DPRINTF, fatal, gem5::AddrRange::interleaved(), gem5::ArmISA::m, mmapUsingNoReserve, panic, panic_if, sharedBackstore, gem5::AddrRange::size(), and gem5::AddrRange::to_string().

Referenced by PhysicalMemory().

◆ functionalAccess()

void gem5::memory::PhysicalMemory::functionalAccess ( PacketPtr  pkt)

Perform an untimed memory read or write without changing anything but the memory itself.

No stats are affected by this access. In addition to normal accesses this also facilitates print requests.

Parameters
pktPacket performing the access

Definition at line 307 of file physical.cc.

References addrMap, gem5::Packet::getAddrRange(), gem5::Packet::isRequest(), and gem5::ArmISA::m.

◆ getBackingStore()

std::vector<BackingStoreEntry> gem5::memory::PhysicalMemory::getBackingStore ( ) const
inline

Get the pointers to the backing store for external host access.

Note that memory in the guest should be accessed using access() or functionalAccess(). This interface is primarily intended for CPU models using hardware virtualization. Note that memories that are null are not present, and that the backing store may also contain memories that are not part of the OS-visible global address map and thus are allowed to overlap.

Returns
Pointers to the memory backing store

Definition at line 227 of file physical.hh.

References backingStore.

Referenced by gem5::KvmVM::delayedStartup().

◆ getConfAddrRanges()

AddrRangeList gem5::memory::PhysicalMemory::getConfAddrRanges ( ) const

Get the memory ranges for all memories that are to be reported to the configuration table.

The ranges are merged before they are returned such that any interleaved ranges appear as a single range.

Returns
All configuration table memory ranges

Definition at line 262 of file physical.cc.

References addrMap, and gem5::MipsISA::r.

Referenced by gem5::ArmSemihosting::gatherHeapInfo(), gem5::ArmISA::FsLinux::initState(), and gem5::System::System().

◆ isMemAddr()

bool gem5::memory::PhysicalMemory::isMemAddr ( Addr  addr) const

Check if a physical address is within a range of a memory that is part of the global address map.

Parameters
addrA physical address
Returns
Whether the address corresponds to a memory

Definition at line 256 of file physical.cc.

References gem5::X86ISA::addr, and addrMap.

Referenced by gem5::System::isMemAddr().

◆ name()

const std::string gem5::memory::PhysicalMemory::name ( ) const
inline

Return the name for debugging and for creation of sections for checkpointing.

Definition at line 187 of file physical.hh.

References _name.

Referenced by serializeStore().

◆ operator=()

PhysicalMemory& gem5::memory::PhysicalMemory::operator= ( const PhysicalMemory )
private

◆ serialize()

void gem5::memory::PhysicalMemory::serialize ( CheckpointOut cp) const
overridevirtual

Serialize all the memories in the system.

This is independent of the logical memory layout, and the serialization only sees the contigous backing store, independent of how this maps to logical memories in the guest system.

Parameters
osstream to serialize to

Implements gem5::Serializable.

Definition at line 316 of file physical.cc.

References backingStore, gem5::csprintf(), gem5::MipsISA::l, gem5::RiscvISA::locked_addrs, gem5::ArmISA::m, memories, gem5::ArmISA::s, SERIALIZE_CONTAINER, SERIALIZE_SCALAR, and serializeStore().

◆ serializeStore()

void gem5::memory::PhysicalMemory::serializeStore ( CheckpointOut cp,
unsigned int  store_id,
AddrRange  range,
uint8_t *  pmem 
) const

Serialize a specific store.

Parameters
store_idUnique identifier of this backing store
rangeThe address range of this backing store
pmemThe host pointer to this backing store

Definition at line 346 of file physical.cc.

References gem5::CheckpointIn::dir(), DPRINTF, fatal, name(), SERIALIZE_SCALAR, gem5::AddrRange::size(), and sc_dt::to_string().

Referenced by serialize().

◆ totalSize()

uint64_t gem5::memory::PhysicalMemory::totalSize ( ) const
inline

Get the total physical memory size.

Returns
The sum of all memory sizes

Definition at line 213 of file physical.hh.

References size.

◆ unserialize()

void gem5::memory::PhysicalMemory::unserialize ( CheckpointIn cp)
overridevirtual

Unserialize the memories in the system.

As with the serialization, this action is independent of how the address ranges are mapped to logical memories in the guest system.

Implements gem5::Serializable.

Definition at line 393 of file physical.cc.

References addrMap, gem5::csprintf(), gem5::ArmISA::i, gem5::ArmISA::m, UNSERIALIZE_CONTAINER, UNSERIALIZE_SCALAR, and unserializeStore().

◆ unserializeStore()

void gem5::memory::PhysicalMemory::unserializeStore ( CheckpointIn cp)

Unserialize a specific backing store, identified by a section.

Definition at line 418 of file physical.cc.

References backingStore, DPRINTF, fatal, gem5::CheckpointIn::getCptDir(), gem5::AddrRange::size(), UNSERIALIZE_SCALAR, and gem5::RiscvISA::x.

Referenced by unserialize().

Member Data Documentation

◆ _name

std::string gem5::memory::PhysicalMemory::_name
private

Definition at line 128 of file physical.hh.

Referenced by name().

◆ addrMap

AddrRangeMap<AbstractMemory*, 1> gem5::memory::PhysicalMemory::addrMap
private

◆ backingStore

std::vector<BackingStoreEntry> gem5::memory::PhysicalMemory::backingStore
private

◆ memories

std::vector<AbstractMemory*> gem5::memory::PhysicalMemory::memories
private

Definition at line 134 of file physical.hh.

Referenced by PhysicalMemory(), and serialize().

◆ mmapUsingNoReserve

const bool gem5::memory::PhysicalMemory::mmapUsingNoReserve
private

Definition at line 140 of file physical.hh.

Referenced by createBackingStore().

◆ sharedBackstore

const std::string gem5::memory::PhysicalMemory::sharedBackstore
private

Definition at line 142 of file physical.hh.

Referenced by createBackingStore().

◆ size

uint64_t gem5::memory::PhysicalMemory::size
private

Definition at line 137 of file physical.hh.

Referenced by PhysicalMemory(), and totalSize().


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

Generated on Tue Sep 21 2021 12:31:29 for gem5 by doxygen 1.8.17