9 releases

0.5.3 Jan 9, 2023
0.5.2 Jan 5, 2023
0.5.1 Dec 17, 2022
0.5.0 Nov 15, 2022
0.3.1 Aug 27, 2022

#293 in Embedded development

31 downloads per month
Used in safe_drive

Custom license

52KB
1K SLoC

memac: Memory allocator using slab and buddy allocators

Usage

First of all, allocate 64KiB aligned memory regions for slab and buddy allocators.

#![feature(start)]

use memac;
use libc::{posix_memalign, c_void};

#[global_allocator]
static mut ALLOC: memac::Allocator<memac::budyy::Buddy32M> = memac::Allocator::new();

fn main() {
    println!("Hello, world!");
}

const HEAP_SIZE: usize = 32 * 1024 * 1024; // 32MiB

#[start]
fn start(_argc: isize, _argv: *const *const u8) -> isize {
    // initialize memory
    unsafe {
        // allocate memory
        let mut ptr: *mut c_void = std::ptr::null_mut();
        if posix_memalign(&mut ptr, memac::ALIGNMENT, HEAP_SIZE) != 0 {
            panic!("posix_memalign");
        }
        ALLOC.init(ptr as usize, HEAP_SIZE);
    }

    main();
    0
}
[dependencies]
libc = "0.2"
memac = "0.5"

memac::Allocator<memac::budyy::Buddy32M> means that the slab allocator uses the buddy allocator to allocate slabs. If a requested size is greater than (65512 - 8) bytes, the buddy allocator is used to allocate memory.

memac::Allocator<memac::pager::PageManager> means that the allocator uses the page manager to allocate slabs. If a requested size is greater than (65512 - 8) bytes, the page manager is used to allocate memory. If a requested size is greater that 64K bytes, the allocation will fail.

Dependencies

~0–29MB
~360K SLoC