Struct mmtk::policy::sft_map::sparse_chunk_map::SFTSparseChunkMap

pub struct SFTSparseChunkMap {
    sft: Vec<SFTRefStorage>,
}

The chunk map is a sparse table. It has one entry for each chunk in the address space we may use.

Fields

sft: Vec<SFTRefStorage>

Implementations

impl SFTSparseChunkMap

pub fn new() -> Self

fn log_update( &self, space: &(dyn SFT + Sync + 'static), start: Address, bytes: usize )

fn trace_sft_map(&self)

fn print_sft_map(&self) -> String

fn set(&self, chunk: usize, sft: &(dyn SFT + Sync + 'static))

Trait Implementations

impl SFTMap for SFTSparseChunkMap

unsafe fn update( &self, space: *const dyn SFT + Sync + 'static, start: Address, bytes: usize )

Update SFT map for the given address range. It should be used when we acquire new memory and use it as part of a space. For example, the cases include:

1. when a space grows, 2. when initializing a contiguous space, 3. when ensure_mapped() is called on a space.

fn has_sft_entry(&self, addr: Address) -> bool

Check if the address has an SFT entry in the map (including an empty SFT entry). This is mostly a bound check to make sure that we won’t have an index-out-of-bound error. For the sake of performance, the implementation of other methods in this trait (such as get_unchecked(), update() and clear()) does not need to do this check implicitly. Instead, they assume the address has a valid entry in the SFT. If an address could be arbitary, they should call this method as a pre-check before they call those methods in the trait. We also provide a method get_checked() which includes this check, and will return an empty SFT if the address is out of bound.

fn get_side_metadata(&self) -> Option<&SideMetadataSpec>

Get the side metadata spec this SFT map uses.

fn get_checked(&self, address: Address) -> &dyn SFT

Get SFT for the address. The address can be arbitrary. For out-of-bound access, an empty SFT will be returned. We only provide the checked version for get(), as it may be used to query arbitrary objects and addresses. Other methods like update/clear/etc are mostly used inside MMTk, and in most cases, we know that they are within our space address range.

unsafe fn get_unchecked(&self, address: Address) -> &dyn SFT

Get SFT for the address. The address must have a valid SFT entry in the table (e.g. from an object reference, or from an address that is known to be in our spaces). Otherwise, use get_checked().

unsafe fn clear(&self, chunk_start: Address)

Clear SFT for the address. The address must have a valid SFT entry in the table.

fn notify_space_creation(&mut self, _space: *const dyn SFT + Sync + 'static)

Notify the SFT map for space creation. DenseChunkMap needs to create an entry for the space.

unsafe fn eager_initialize( &mut self, space: *const dyn SFT + Sync + 'static, start: Address, bytes: usize )

Eagerly initialize the SFT table. For most implementations, it could be the same as update(). However, we need this as a seprate method for SFTDenseChunkMap, as it needs to map side metadata first before setting the table.

impl Sync for SFTSparseChunkMap