org.mmtk.plan.semispace

Class SSMutator

java.lang.Object

org.mmtk.plan.MutatorContext

org.mmtk.plan.SimpleMutator

org.mmtk.plan.StopTheWorldMutator

org.mmtk.plan.semispace.SSMutator

Direct Known Subclasses:

GCTraceMutator, SSGCspyMutator, UsePrimitiveWriteBarriersMutator

public class SSMutator
extends StopTheWorldMutator

This class implements per-mutator thread behavior and state for the SS plan, which implements a full-heap semi-space collector.

Specifically, this class defines SS mutator-time allocation and per-mutator thread collection semantics (flushing and restoring per-mutator allocator state).

See SS for an overview of the semi-space algorithm.

See Also:

SS, SSCollector, StopTheWorldMutator, MutatorContext

Field Summary

Fields

Modifier and Type	Field and Description
protected CopyLocal	ss Instance fields

Fields inherited from class org.mmtk.plan.MutatorContext

immortal, lgcode, log, los, nonmove, smcode

Constructor Summary

Constructors

Constructor and Description
SSMutator() Constructor

Method Summary

Modifier and Type	Method and Description
Address	alloc(int bytes, int align, int offset, int allocator, int site) Allocate memory for an object.
void	collectionPhase(short phaseId, boolean primary) Perform a per-mutator collection phase.
Allocator	getAllocatorFromSpace(Space space) Return the allocator instance associated with a space space, for this plan instance.
void	initMutator(int id) Called before the MutatorContext is used, but after the context has been fully registered and is visible to collection.
void	postAlloc(ObjectReference object, ObjectReference typeRef, int bytes, int allocator) Perform post-allocation actions.
void	show() Show the status of each of the allocators.

Methods inherited from class org.mmtk.plan.MutatorContext

addressBulkCopy, addressRead, addressTryCompareAndSwap, addressWrite, assertRemsetsFlushed, booleanBulkCopy, booleanRead, booleanWrite, byteBulkCopy, byteRead, byteWrite, charBulkCopy, charRead, charWrite, checkAllocator, deinitMutator, doubleBulkCopy, doubleRead, doubleWrite, extentBulkCopy, extentRead, extentWrite, floatBulkCopy, floatRead, floatWrite, flush, flushRememberedSets, getId, getLog, intBulkCopy, intRead, intTryCompareAndSwap, intWrite, javaLangReferenceReadBarrier, longBulkCopy, longRead, longTryCompareAndSwap, longWrite, objectReferenceBulkCopy, objectReferenceNonHeapRead, objectReferenceNonHeapWrite, objectReferenceRead, objectReferenceTryCompareAndSwap, objectReferenceWrite, offsetBulkCopy, offsetRead, offsetWrite, shortBulkCopy, shortRead, shortWrite, wordBulkCopy, wordRead, wordTryCompareAndSwap, wordWrite

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Detail

ss

protected final CopyLocal ss

Instance fields

Constructor Detail

SSMutator

public SSMutator()

Constructor

Method Detail

initMutator

public void initMutator(int id)

Called before the MutatorContext is used, but after the context has been fully registered and is visible to collection.

Overrides:

initMutator in class MutatorContext

Parameters:

id - The id of this mutator context.

alloc

public Address alloc(int bytes,
                     int align,
                     int offset,
                     int allocator,
                     int site)

Allocate memory for an object.

Overrides:

alloc in class MutatorContext

Parameters:

bytes - The number of bytes required for the object.

align - Required alignment for the object.

offset - Offset associated with the alignment.

allocator - The allocator associated with this request.

site - Allocation site

Returns:

The low address of the allocated chunk.

postAlloc

public void postAlloc(ObjectReference object,
                      ObjectReference typeRef,
                      int bytes,
                      int allocator)

Description copied from class: MutatorContext

Perform post-allocation actions. For many allocators none are required.

Overrides:

postAlloc in class MutatorContext

Parameters:

object - The newly allocated object

typeRef - the type reference for the instance being created

bytes - The size of the space to be allocated (in bytes)

allocator - The allocator number to be used for this allocation

getAllocatorFromSpace

public Allocator getAllocatorFromSpace(Space space)

Description copied from class: MutatorContext

Return the allocator instance associated with a space space, for this plan instance.

Overrides:

getAllocatorFromSpace in class MutatorContext

Parameters:

space - The space for which the allocator instance is desired.

Returns:

The allocator instance associated with this plan instance which is allocating into space, or null if no appropriate allocator can be established.

collectionPhase

public void collectionPhase(short phaseId,
                            boolean primary)

Perform a per-mutator collection phase. This is executed by one collector thread on behalf of a mutator thread.

Overrides:

collectionPhase in class SimpleMutator

Parameters:

phaseId - The unique phase identifier

primary - Should this thread be used to execute any single-threaded local operations?

show

public final void show()

Show the status of each of the allocators.