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VILLASnode/common/include/villas/memory.hpp
Steffen Vogel 6c582cbf91 Make project REUSE compliant
Signed-off-by: Steffen Vogel <steffen.vogel@opal-rt.com>
2024-02-29 18:58:07 +01:00

345 lines
8.6 KiB
C++

/* Memory management.
*
* Author: Daniel Krebs <github@daniel-krebs.net>
* SPDX-FileCopyrightText: 2014-2023 Institute for Automation of Complex Power Systems, RWTH Aachen University
* SPDX-License-Identifier: Apache-2.0
*/
#pragma once
#include <string>
#include <unistd.h>
#include <villas/log.hpp>
#include <villas/memory_manager.hpp>
namespace villas {
// Basic memory block backed by an address space in the memory graph
//
// This is a generic representation of a chunk of memory in the system. It can
// reside anywhere and represent different types of memory.
class MemoryBlock {
public:
using deallocator_fn = std::function<void(MemoryBlock*)>;
using Ptr = std::shared_ptr<MemoryBlock>;
using UniquePtr = std::unique_ptr<MemoryBlock, deallocator_fn>;
// cppcheck-suppress passedByValue
MemoryBlock(size_t offset, size_t size, MemoryManager::AddressSpaceId addrSpaceId) :
offset(offset), size(size), addrSpaceId(addrSpaceId) {}
MemoryManager::AddressSpaceId getAddrSpaceId() const
{
return addrSpaceId;
}
size_t getSize() const
{
return size;
}
size_t getOffset() const
{
return offset;
}
protected:
size_t offset; // Offset (or address) inside address space
size_t size; // Size in bytes of this block
MemoryManager::AddressSpaceId addrSpaceId; // Identifier in memory graph
};
// Wrapper for a MemoryBlock to access the underlying memory directly
//
// The underlying memory block has to be accessible for the current process,
// that means it has to be mapped accordingly and registered to the global
// memory graph.
// Furthermore, this wrapper can be owning the memory block when initialized
// with a moved unique pointer. Otherwise, it just stores a reference to the
// memory block and it's the users responsibility to take care that the memory
// block is valid.
template<typename T>
class MemoryAccessor {
public:
using Type = T;
// Take ownership of the MemoryBlock
MemoryAccessor(std::unique_ptr<MemoryBlock, MemoryBlock::deallocator_fn> mem) :
translation(MemoryManager::get().getTranslationFromProcess(mem->getAddrSpaceId())),
memoryBlock(std::move(mem))
{ }
// Just act as an accessor, do not take ownership of MemoryBlock
MemoryAccessor(const MemoryBlock &mem) :
translation(MemoryManager::get().getTranslationFromProcess(mem.getAddrSpaceId()))
{ }
MemoryAccessor(const MemoryTranslation &translation) :
translation(translation)
{ }
T & operator*() const
{
return *reinterpret_cast<T*>(translation.getLocalAddr(0));
}
T & operator[](size_t idx) const
{
const size_t offset = sizeof(T) * idx;
return *reinterpret_cast<T*>(translation.getLocalAddr(offset));
}
T* operator&() const
{
return reinterpret_cast<T*>(translation.getLocalAddr(0));
}
T* operator->() const
{
return reinterpret_cast<T*>(translation.getLocalAddr(0));
}
const MemoryBlock&
getMemoryBlock() const
{
if (not memoryBlock) throw std::bad_alloc(); else return *memoryBlock;
}
private:
// Cached memory translation for fast access
MemoryTranslation translation;
// Take the unique pointer in case user wants this class to have ownership
std::unique_ptr<MemoryBlock, MemoryBlock::deallocator_fn> memoryBlock;
};
// Base memory allocator
//
// Note the usage of CRTP idiom here to access methods of derived allocators.
// The concept is explained here at [1].
//
// [1] https://en.wikipedia.org/wiki/Curiously_recurring_template_pattern
template<typename DerivedAllocator>
class BaseAllocator {
public:
// memoryAddrSpaceId: memory that is managed by this allocator
BaseAllocator(MemoryManager::AddressSpaceId memoryAddrSpaceId) :
memoryAddrSpaceId(memoryAddrSpaceId)
{
// CRTP
derivedAlloc = static_cast<DerivedAllocator*>(this);
std::string loggerName = fmt::format("memory:", derivedAlloc->getName());
logger = logging.get(loggerName);
// Default deallocation callback
free = [&](MemoryBlock* mem) {
logger->warn("no free callback defined for addr space {}, not freeing",
mem->getAddrSpaceId());
removeMemoryBlock(*mem);
};
}
BaseAllocator(std::unique_ptr<MemoryBlock, MemoryBlock::deallocator_fn> mem) :
BaseAllocator(mem->getAddrSpaceId())
{
// cppcheck-suppress useInitializationList
memoryBlock = std::move(mem);
derivedAlloc = nullptr;
}
virtual
std::unique_ptr<MemoryBlock, MemoryBlock::deallocator_fn>
allocateBlock(size_t size) = 0;
template<typename T>
MemoryAccessor<T>
allocate(size_t num)
{
if (num == 0) {
// Doesn't make sense to allocate an empty block
logger->error("Trying to allocate empty memory");
throw std::bad_alloc();
}
const size_t size = num * sizeof(T);
auto mem = allocateBlock(size);
// Check if the allocated memory is really accessible by writing to the
// allocated memory and reading back. Exponentially increase offset to
// speed up testing.
MemoryAccessor<volatile uint8_t> byteAccessor(*mem);
size_t idx = 0;
for (int i = 0; idx < mem->getSize(); i++, idx = (1 << i)) {
auto val = static_cast<uint8_t>(i);
byteAccessor[idx] = val;
if (byteAccessor[idx] != val) {
logger->error("Cannot access allocated memory");
throw std::bad_alloc();
}
}
return MemoryAccessor<T>(std::move(mem));
}
protected:
void insertMemoryBlock(const MemoryBlock &mem)
{
auto & mm = MemoryManager::get();
mm.createMapping(mem.getOffset(), 0, mem.getSize(),
derivedAlloc->getName(),
memoryAddrSpaceId,
mem.getAddrSpaceId());
}
void removeMemoryBlock(const MemoryBlock &mem)
{
// This will also remove any mapping to and from the memory block
auto & mm = MemoryManager::get();
mm.removeAddressSpace(mem.getAddrSpaceId());
}
MemoryManager::AddressSpaceId getAddrSpaceId() const
{
return memoryAddrSpaceId;
}
MemoryBlock::deallocator_fn free;
Logger logger;
// Optional, if allocator should own the memory block
std::unique_ptr<MemoryBlock, MemoryBlock::deallocator_fn> memoryBlock;
private:
MemoryManager::AddressSpaceId memoryAddrSpaceId;
DerivedAllocator* derivedAlloc;
};
// Linear memory allocator
//
// This is the simplest kind of allocator. The idea is to keep a pointer at the
// first memory address of your memory chunk and move it every time an
// allocation is done. Due to its simplicity, this allocator doesn't allow
// specific positions of memory to be freed. Usually, all memory is freed
// together.
class LinearAllocator : public BaseAllocator<LinearAllocator> {
public:
LinearAllocator(MemoryManager::AddressSpaceId memoryAddrSpaceId,
size_t memorySize,
size_t internalOffset = 0);
LinearAllocator(std::unique_ptr<MemoryBlock, MemoryBlock::deallocator_fn> mem) :
LinearAllocator(mem->getAddrSpaceId(), mem->getSize())
{
memoryBlock = std::move(mem);
}
size_t getAvailableMemory() const
{
return memorySize - nextFreeAddress;
}
size_t getSize() const
{
return memorySize;
}
std::string getName() const;
std::unique_ptr<MemoryBlock, MemoryBlock::deallocator_fn>
allocateBlock(size_t size);
private:
static constexpr
size_t alignBytes = sizeof(uintptr_t);
static constexpr
size_t alignMask = alignBytes - 1;
size_t getAlignmentPadding(uintptr_t addr) const
{
return (alignBytes - (addr & alignMask)) & alignMask;
}
size_t nextFreeAddress; // Next chunk will be allocated here
size_t memorySize; // Total size of managed memory
size_t internalOffset; // Offset in address space (usually 0)
size_t allocationCount; // Number of individual allocations present
};
// Wrapper around mmap() to create villas memory blocks
//
// This class simply wraps around mmap() and munmap() to allocate memory in the
// host memory via the OS.
class HostRam {
public:
class HostRamAllocator : public BaseAllocator<HostRamAllocator> {
public:
HostRamAllocator();
std::string getName() const
{
return "HostRamAlloc";
}
std::unique_ptr<MemoryBlock, MemoryBlock::deallocator_fn>
allocateBlock(size_t size);
};
static
HostRamAllocator& getAllocator()
{
return allocator;
}
private:
static
HostRamAllocator allocator;
};
class HostDmaRam {
public:
class HostDmaRamAllocator : public LinearAllocator {
public:
HostDmaRamAllocator(int num);
virtual
~HostDmaRamAllocator();
std::string getName() const
{
return getUdmaBufName(num);
}
private:
int num;
};
static
HostDmaRamAllocator&
getAllocator(int num = 0);
private:
static
std::map<int, std::unique_ptr<HostDmaRamAllocator>> allocators;
static
std::string
getUdmaBufName(int num);
static
std::string
getUdmaBufBasePath(int num);
static
size_t
getUdmaBufBufSize(int num);
static
uintptr_t
getUdmaBufPhysAddr(int num);
};
} // namespace villas