/**
* Notify that the concurrent phase has completed successfully. This must only be called by a
* single thread after it has determined that the phase has been completed successfully.
*/
public static void notifyConcurrentPhaseComplete() {
if (Options.verbose.getValue() >= 2) {
Log.write("< Concurrent phase ");
Log.write(getName(concurrentPhaseId));
Log.writeln(" complete >");
}
/* Concurrent phase is complete*/
concurrentPhaseId = 0;
/* Remove it from the stack */
popScheduledPhase();
/* Pop the next phase off the stack */
int nextScheduledPhase = getNextPhase();
if (nextScheduledPhase > 0) {
short schedule = getSchedule(nextScheduledPhase);
/* A concurrent phase, lets wake up and do it all again */
if (schedule == SCHEDULE_CONCURRENT) {
concurrentPhaseId = getPhaseId(nextScheduledPhase);
scheduleConcurrentWorkers();
return;
}
/* Push phase back on and resume atomic collection */
pushScheduledPhase(nextScheduledPhase);
VM.collection.triggerAsyncCollection(Collection.INTERNAL_PHASE_GC_TRIGGER);
}
}
@Inline
private boolean acquireRecyclableBlockAddressOrder() {
if (recyclableExhausted) {
if (VM.VERIFY_ASSERTIONS && Options.verbose.getValue() >= 9) {
Log.writeln("[no recyclable available]");
}
return false;
}
int markState = 0;
boolean usable = false;
while (!usable) {
Address next = recyclableBlock.plus(BYTES_IN_BLOCK);
if (recyclableBlock.isZero() || ImmixSpace.isRecycleAllocChunkAligned(next)) {
recyclableBlock = space.acquireReusableBlocks();
if (recyclableBlock.isZero()) {
recyclableExhausted = true;
if (VM.VERIFY_ASSERTIONS && Options.verbose.getValue() >= 9) {
Log.writeln("[recyclable exhausted]");
}
line = LINES_IN_BLOCK;
return false;
}
} else {
recyclableBlock = next;
}
markState = Block.getBlockMarkState(recyclableBlock);
usable = (markState > 0 && markState <= ImmixSpace.getReusuableMarkStateThreshold(copy));
if (copy && Block.isDefragSource(recyclableBlock)) usable = false;
}
if (VM.VERIFY_ASSERTIONS) VM.assertions._assert(!Block.isUnused(recyclableBlock));
Block.setBlockAsReused(recyclableBlock);
lineUseCount += (LINES_IN_BLOCK - markState);
return true; // found something good
}
/** Notify that the concurrent phase has not finished, and must be re-attempted. */
public static void notifyConcurrentPhaseIncomplete() {
if (Options.verbose.getValue() >= 2) {
Log.write("< Concurrent phase ");
Log.write(getName(concurrentPhaseId));
Log.writeln(" incomplete >");
}
scheduleConcurrentWorkers();
}
/**
* This method logs a message with preprended thread id, if the verbosity level is greater or
* equal to the passed level.
*
* @param minVerbose The required verbosity level
* @param message The message to display
*/
@Inline
protected final void logMessage(int minVerbose, String message) {
if (Options.verbose.getValue() >= minVerbose) {
Log.prependThreadId();
Log.write(" ");
Log.writeln(message);
}
}
/**
* Log a message from within 'poll'
*
* @param space
* @param message
*/
private void logPoll(Space space, String message) {
if (Options.verbose.getValue() >= 3) {
Log.write(" [POLL] ");
Log.write(space.getName());
Log.write(": ");
Log.writeln(message);
}
}
/**
* Send the data and summary for this stream.
*
* @param event The event
* @param numTiles The number of tiles to send (which may be less than maxTileNum)
*/
public void send(int event, int numTiles) {
if (DEBUG) {
Log.write("sending ");
Log.write(numTiles);
Log.writeln(" int values");
}
serverSpace.stream(streamId, numTiles);
for (int index = 0; index < numTiles; index++) serverSpace.streamIntValue(data[index]);
serverSpace.streamEnd();
sendSummary();
}
/**
* The VM is about to exit. Perform any clean up operations.
*
* @param value The exit value
*/
@Interruptible
public void notifyExit(int value) {
if (Options.harnessAll.getValue()) harnessEnd();
if (Options.verbose.getValue() == 1) {
Log.write("[End ");
totalTime.printTotalSecs();
Log.writeln(" s]");
} else if (Options.verbose.getValue() == 2) {
Log.write("[End ");
totalTime.printTotalMillis();
Log.writeln(" ms]");
}
if (Options.verboseTiming.getValue()) printDetailedTiming(true);
}
/**
* Is the specified object live?
*
* @param object The object.
* @return True if the object is live.
*/
@Inline
public boolean isLive(ObjectReference object) {
Space space = Space.getSpaceForObject(object);
if (space == Plan.loSpace) return Plan.loSpace.isLive(object);
else if (space == Plan.ploSpace) return Plan.ploSpace.isLive(object);
else if (Plan.USE_CODE_SPACE && space == Plan.smallCodeSpace)
return Plan.smallCodeSpace.isLive(object);
else if (Plan.USE_CODE_SPACE && space == Plan.largeCodeSpace)
return Plan.largeCodeSpace.isLive(object);
else if (space == null) {
if (VM.VERIFY_ASSERTIONS) {
Log.write("space failure: ");
Log.writeln(object);
}
}
return true;
}
/**
* Notify that the current thread believes that a concurrent collection phase is complete.
*
* @return True if this was the last thread.
*/
public static boolean completeConcurrentPhase() {
boolean result = false;
concurrentWorkersLock.acquire();
if (VM.VERIFY_ASSERTIONS) VM.assertions._assert(allowConcurrentWorkersActive);
concurrentWorkersActive--;
if (concurrentWorkersActive == 0) {
allowConcurrentWorkersActive = false;
result = true;
}
if (Options.verbose.getValue() >= 3) {
Log.write("< Concurrent worker ");
Log.write(concurrentWorkersActive);
Log.write(" completed phase ");
Log.write(getName(concurrentPhaseId));
Log.writeln(" >");
}
concurrentWorkersLock.release();
return result;
}
/**
* Perform some concurrent collection work.
*
* @param phaseId The unique phase identifier
*/
@Unpreemptible
public void concurrentCollectionPhase(short phaseId) {
if (phaseId == Concurrent.CONCURRENT_CLOSURE) {
if (VM.VERIFY_ASSERTIONS) {
VM.assertions._assert(!Plan.gcInProgress());
}
TraceLocal trace = getCurrentTrace();
while (!trace.incrementalTrace(100)) {
if (group.isAborted()) {
trace.flush();
break;
}
}
if (rendezvous() == 0) {
continueCollecting = false;
if (!group.isAborted()) {
/* We are responsible for ensuring termination. */
if (Options.verbose.getValue() >= 2) Log.writeln("< requesting mutator flush >");
VM.collection.requestMutatorFlush();
if (Options.verbose.getValue() >= 2) Log.writeln("< mutators flushed >");
if (concurrentTraceComplete()) {
continueCollecting = Phase.notifyConcurrentPhaseComplete();
} else {
continueCollecting = true;
Phase.notifyConcurrentPhaseIncomplete();
}
}
}
rendezvous();
return;
}
Log.write("Concurrent phase ");
Log.write(Phase.getName(phaseId));
Log.writeln(" not handled.");
VM.assertions.fail("Concurrent phase not handled!");
}
/**
* Trace a reference during GC. This involves determining which collection policy applies and
* calling the appropriate <code>trace</code> method.
*
* @param target The object the interior edge points within.
* @param slot The location of the interior edge.
* @param root True if this is a root edge.
*/
public final void processInteriorEdge(ObjectReference target, Address slot, boolean root) {
Address interiorRef = slot.loadAddress();
Offset offset = interiorRef.diff(target.toAddress());
ObjectReference newTarget = traceObject(target, root);
if (VM.VERIFY_ASSERTIONS) {
if (offset.sLT(Offset.zero()) || offset.sGT(Offset.fromIntSignExtend(1 << 24))) {
// There is probably no object this large
Log.writeln("ERROR: Suspiciously large delta to interior pointer");
Log.write(" object base = ");
Log.writeln(target);
Log.write(" interior reference = ");
Log.writeln(interiorRef);
Log.write(" delta = ");
Log.writeln(offset);
VM.assertions._assert(false);
}
}
slot.store(newTarget.toAddress().plus(offset));
}
/** Attempt to begin execution of a concurrent collection phase. */
public static boolean startConcurrentPhase() {
boolean result = false;
concurrentWorkersLock.acquire();
if (concurrentPhaseActive()) {
if (allowConcurrentWorkersActive) {
concurrentWorkersActive++;
result = true;
}
VM.activePlan.collector().clearResetConcurrentWork();
}
if (Options.verbose.getValue() >= 2) {
if (result) {
Log.write("< Concurrent worker ");
Log.write(concurrentWorkersActive - 1);
Log.write(" started phase ");
Log.write(getName(concurrentPhaseId));
Log.writeln(" >");
} else {
Log.writeln("< worker failed in attempt to start phase >");
}
}
concurrentWorkersLock.release();
return result;
}
/** Process the phase stack. This method is called by multiple threads. */
private static boolean processPhaseStack(boolean resume) {
int order = VM.collection.rendezvous(1001);
final boolean primary = order == 1;
boolean log = Options.verbose.getValue() >= 6;
boolean logDetails = Options.verbose.getValue() >= 7;
if (primary && resume) {
if (VM.VERIFY_ASSERTIONS) VM.assertions._assert(!Phase.isPhaseStackEmpty());
if (VM.VERIFY_ASSERTIONS) VM.assertions._assert(!Plan.gcInProgress());
Plan.setGCStatus(Plan.GC_PROPER);
}
/* In order to reduce the need for synchronization, we keep an odd or even
* counter for the number of phases processed. As each phase has a single
* rendezvous it is only possible to be out by one so the odd or even counter
* protects us. */
boolean isEvenPhase = true;
if (primary) {
/* First phase will be even, so we say we are odd here so that the next phase set is even*/
setNextPhase(false, getNextPhase(), false);
}
/* Make sure everyone sees the first phase */
VM.collection.rendezvous(1002);
/* Global and Collector instances used in phases */
Plan plan = VM.activePlan.global();
CollectorContext collector = VM.activePlan.collector();
/* The main phase execution loop */
int scheduledPhase;
while ((scheduledPhase = getCurrentPhase(isEvenPhase)) > 0) {
short schedule = getSchedule(scheduledPhase);
short phaseId = getPhaseId(scheduledPhase);
Phase p = getPhase(phaseId);
/* Start the timer(s) */
if (primary) {
if (resume) {
resumeComplexTimers();
}
if (p.timer != null) p.timer.start();
if (startComplexTimer > 0) {
Phase.getPhase(startComplexTimer).timer.start();
startComplexTimer = 0;
}
}
if (log) {
Log.write("Execute ");
p.logPhase();
}
/* Execute a single simple scheduled phase */
switch (schedule) {
/* Global phase */
case SCHEDULE_GLOBAL:
{
if (logDetails) Log.writeln(" as Global...");
if (primary) plan.collectionPhase(phaseId);
break;
}
/* Collector phase */
case SCHEDULE_COLLECTOR:
{
if (logDetails) Log.writeln(" as Collector...");
collector.collectionPhase(phaseId, primary);
break;
}
/* Mutator phase */
case SCHEDULE_MUTATOR:
{
if (logDetails) Log.writeln(" as Mutator...");
/* Iterate through all mutator contexts */
MutatorContext mutator;
while ((mutator = VM.activePlan.getNextMutator()) != null) {
mutator.collectionPhase(phaseId, primary);
}
break;
}
/* Concurrent phase */
case SCHEDULE_CONCURRENT:
{
/* We are yielding to a concurrent collection phase */
if (logDetails) Log.writeln(" as Concurrent, yielding...");
if (primary) {
concurrentPhaseId = phaseId;
scheduleConcurrentWorkers();
/* Concurrent phase, we need to stop gc */
Plan.setGCStatus(Plan.NOT_IN_GC);
}
VM.collection.rendezvous(1003);
if (primary) {
pauseComplexTimers();
}
return false;
}
default:
{
/* getNextPhase has done the wrong thing */
VM.assertions.fail("Invalid schedule in Phase.processPhaseStack");
break;
}
}
if (primary) {
/* Set the next phase by processing the stack */
int next = getNextPhase();
boolean needsResetRendezvous =
(next > 0) && (schedule == SCHEDULE_MUTATOR && getSchedule(next) == SCHEDULE_MUTATOR);
setNextPhase(isEvenPhase, next, needsResetRendezvous);
}
/* Sync point after execution of a phase */
VM.collection.rendezvous(1004);
/* Mutator phase reset */
if (primary && schedule == SCHEDULE_MUTATOR) {
VM.activePlan.resetMutatorIterator();
}
/* At this point, in the case of consecutive phases with mutator
* scheduling, we have to double-synchronize to ensure all
* collector threads see the reset mutator counter. */
if (needsMutatorResetRendezvous(isEvenPhase)) {
VM.collection.rendezvous(1005);
}
/* Stop the timer(s) */
if (primary) {
if (p.timer != null) p.timer.stop();
if (stopComplexTimer > 0) {
Phase.getPhase(stopComplexTimer).timer.stop();
stopComplexTimer = 0;
}
}
/* Flip the even / odd phase sense */
isEvenPhase = !isEvenPhase;
resume = false;
}
/* Phase stack exhausted so we return true */
return true;
}
public final void printUsedPages() {
Log.write("reserved = ");
Log.write(Conversions.pagesToMBytes(getPagesReserved()));
Log.write(" MB (");
Log.write(getPagesReserved());
Log.write(" pgs)");
Log.write(" total = ");
Log.write(Conversions.pagesToMBytes(getTotalPages()));
Log.write(" MB (");
Log.write(getTotalPages());
Log.write(" pgs)");
Log.writeln();
}
/** Print out statistics at the end of a GC */
public final void printPostStats() {
if ((Options.verbose.getValue() == 1) || (Options.verbose.getValue() == 2)) {
Log.write("-> ");
Log.writeDec(Conversions.pagesToBytes(getPagesUsed()).toWord().rshl(10));
Log.write("KB ");
if (Options.verbose.getValue() == 1) {
totalTime.printLast();
Log.writeln(" ms]");
} else {
Log.write("End ");
totalTime.printTotal();
Log.writeln(" ms]");
}
}
if (Options.verbose.getValue() > 2) {
Log.write(" After Collection: ");
Space.printUsageMB();
if (Options.verbose.getValue() >= 4) {
Log.write(" ");
Space.printUsagePages();
}
if (Options.verbose.getValue() >= 5) {
Space.printVMMap();
}
Log.write(" ");
printUsedPages();
Log.write(" Collection time: ");
totalTime.printLast();
Log.writeln(" ms");
}
}
/** Print out statistics at the start of a GC */
public void printPreStats() {
if ((Options.verbose.getValue() == 1) || (Options.verbose.getValue() == 2)) {
Log.write("[GC ");
Log.write(Stats.gcCount());
if (Options.verbose.getValue() == 1) {
Log.write(" Start ");
Plan.totalTime.printTotalSecs();
Log.write(" s");
} else {
Log.write(" Start ");
Plan.totalTime.printTotalMillis();
Log.write(" ms");
}
Log.write(" ");
Log.write(Conversions.pagesToKBytes(getPagesUsed()));
Log.write("KB ");
Log.flush();
}
if (Options.verbose.getValue() > 2) {
Log.write("Collection ");
Log.write(Stats.gcCount());
Log.write(": ");
printUsedPages();
Log.write(" Before Collection: ");
Space.printUsageMB();
if (Options.verbose.getValue() >= 4) {
Log.write(" ");
Space.printUsagePages();
}
if (Options.verbose.getValue() >= 5) {
Space.printVMMap();
}
}
}
/**
* Print pre-collection statistics. In this class we prefix the output indicating whether the
* collection was full heap or not.
*/
public void printPreStats() {
if ((Options.verbose.getValue() >= 1) && (gcFullHeap)) Log.write("[Full heap]");
super.printPreStats();
}
private boolean acquireRecyclableLines(int bytes, int align, int offset) {
while (line < LINES_IN_BLOCK || acquireRecyclableBlock()) {
line = space.getNextAvailableLine(markTable, line);
if (line < LINES_IN_BLOCK) {
int endLine = space.getNextUnavailableLine(markTable, line);
cursor = recyclableBlock.plus(Extent.fromIntSignExtend(line << LOG_BYTES_IN_LINE));
limit = recyclableBlock.plus(Extent.fromIntSignExtend(endLine << LOG_BYTES_IN_LINE));
if (SANITY_CHECK_LINE_MARKS) {
Address tmp = cursor;
while (tmp.LT(limit)) {
if (tmp.loadByte() != (byte) 0) {
Log.write("cursor: ");
Log.writeln(cursor);
Log.write(" limit: ");
Log.writeln(limit);
Log.write("current: ");
Log.write(tmp);
Log.write(" value: ");
Log.write(tmp.loadByte());
Log.write(" line: ");
Log.write(line);
Log.write("endline: ");
Log.write(endLine);
Log.write(" chunk: ");
Log.write(Chunk.align(cursor));
Log.write(" hw: ");
Log.write(Chunk.getHighWater(Chunk.align(cursor)));
Log.writeln(" values: ");
Address tmp2 = cursor;
while (tmp2.LT(limit)) {
Log.write(tmp2.loadByte());
Log.write(" ");
}
Log.writeln();
}
VM.assertions._assert(tmp.loadByte() == (byte) 0);
tmp = tmp.plus(1);
}
}
if (VM.VERIFY_ASSERTIONS && bytes <= BYTES_IN_LINE) {
Address start = alignAllocationNoFill(cursor, align, offset);
Address end = start.plus(bytes);
VM.assertions._assert(end.LE(limit));
}
VM.memory.zero(cursor, limit.diff(cursor).toWord().toExtent());
if (VM.VERIFY_ASSERTIONS && Options.verbose.getValue() >= 9) {
Log.write("Z[");
Log.write(cursor);
Log.write("->");
Log.write(limit);
Log.writeln("]");
}
line = endLine;
if (VM.VERIFY_ASSERTIONS && copy) VM.assertions._assert(!Block.isDefragSource(cursor));
return true;
}
}
return false;
}
/** Print out the status of the allocator (for debugging) */
public final void show() {
Log.write("cursor = ");
Log.write(cursor);
Log.write(" limit = ");
Log.writeln(limit);
}