#pragma once
/*
* Copyright (C) 2024 Brett Terpstra
*
* This program is free software: you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation, either version 3 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program. If not, see .
*/
#ifndef BLT_MMAP_H
#define BLT_MMAP_H
#include
#include
#include
// size of 2mb in bytes
inline constexpr blt::size_t BLT_2MB_SIZE = 2048 * 1024;
inline constexpr blt::size_t BLT_1GB_SIZE = 1048576 * 1024;
namespace blt
{
enum class huge_page_t : blt::u64
{
BLT_2MB_PAGE,
BLT_1GB_PAGE
};
class bad_alloc_t : public std::exception
{
public:
bad_alloc_t() = default;
explicit bad_alloc_t(std::string_view str): str(str)
{}
explicit bad_alloc_t(std::string str): str(std::move(str))
{}
[[nodiscard]] const char* what() const noexcept override
{
return str.c_str();
}
private:
std::string str;
};
/**
* Logging function used for handling mmap errors. call after a failed mmap call.
*/
std::string handle_mmap_error();
inline static constexpr blt::size_t align_size_to(blt::size_t size, blt::size_t align)
{
const blt::size_t MASK = ~(align - 1);
return (size & MASK) + align;
}
void* allocate_huge_pages(huge_page_t page_type, blt::size_t bytes);
void mmap_free(void* ptr, blt::size_t bytes);
class mmap_huge_allocator
{
public:
void* allocate(blt::size_t bytes, huge_page_t page_type) // NOLINT
{
return allocate_huge_pages(page_type, bytes);
}
void deallocate(void* ptr, blt::size_t bytes) // NOLINT
{
mmap_free(ptr, bytes);
}
};
class aligned_huge_allocator
{
public:
void* allocate(blt::size_t bytes) // NOLINT
{
return std::aligned_alloc(BLT_2MB_SIZE, bytes);
}
void deallocate(void* ptr, blt::size_t) // NOLINT
{
std::free(ptr);
}
};
}
#endif //BLT_MMAP_H