Function num_levels_needed

kernel/src/memory/frame_allocator.rs:42–51

Calculate the number of bitmap levels needed Bitmaps are in chunks of 32, so each level multiplies the maximum number of frames by 32.

(num_frames: u64)

/// Bitmaps are in chunks of 32, so each level multiplies the maximum
/// number of frames by 32.
fn num_levels_needed(num_frames: u64) -> usize {
    let mut max_frames = 32;
    let mut levels = 1;

    while num_frames > max_frames {
        levels += 1;
        max_frames *= 32;
    }
    levels
}

#[test_case]
fn test_num_levels_needed() {