Struct mmtk::util::heap::accounting::PageAccounting

pub struct PageAccounting {
    reserved: AtomicUsize,
    committed: AtomicUsize,
}

The struct is used for page usage. Both page resource and side metadata uses this struct to do page accounting.

Fields

reserved: AtomicUsize

The reserved pages. This should be incremented when we are about to allocate pages. Note this is different than quarantining address range. We do not count for quarantined memory.

committed: AtomicUsize

The committed pages. This should be incremented when we successfully allocate pages from the OS.

Implementations

impl PageAccounting

pub fn new() -> Self

pub fn reserve_and_commit(&self, pages: usize)

Inform of both reserving and committing a certain number of pages.

pub fn reserve(&self, pages: usize)

Inform of reserving a certain number of pages. Usually this is called before attempting to allocate memory.

pub fn clear_reserved(&self, pages: usize)

Inform of clearing some reserved pages. This is used when we have reserved some pages but the allocation cannot be satisfied. We can call this to clear the number of reserved pages, so later we can reserve and attempt again.

pub fn commit(&self, pages: usize)

Inform of successfully committing a certain number of pages. This is used after we have reserved pages and successfully allocated those memory.

pub fn release(&self, pages: usize)

Inform of releasing a certain number of pages. The number of pages will be deducted from both reserved and committed pages.

pub fn reset(&self)

Set both reserved and committed pages to zero. This is only used when we completely clear a space.

pub fn get_reserved_pages(&self) -> usize

pub fn get_committed_pages(&self) -> usize

Trait Implementations

impl Default for PageAccounting

fn default() -> Self

Returns the “default value” for a type.