--- a/hotspot/make/solaris/makefiles/sparcWorks.make Fri Oct 15 09:38:20 2010 +0200
+++ b/hotspot/make/solaris/makefiles/sparcWorks.make Fri Oct 15 02:59:48 2010 -0700
@@ -51,9 +51,9 @@
VALIDATED_COMPILER_REVS := 5.8
VALIDATED_C_COMPILER_REVS := 5.8
else
- # Validated compilers for JDK7 are SS12 (5.9) or SS12 update 1 (5.10)
- VALIDATED_COMPILER_REVS := 5.9 5.10
- VALIDATED_C_COMPILER_REVS := 5.9 5.10
+ # Validated compiler for JDK7 is SS12 update 1 + patches (5.10)
+ VALIDATED_COMPILER_REVS := 5.10
+ VALIDATED_C_COMPILER_REVS := 5.10
endif
# Warning messages about not using the above validated versions
--- a/hotspot/src/share/vm/gc_implementation/concurrentMarkSweep/cmsCollectorPolicy.cpp Fri Oct 15 09:38:20 2010 +0200
+++ b/hotspot/src/share/vm/gc_implementation/concurrentMarkSweep/cmsCollectorPolicy.cpp Fri Oct 15 02:59:48 2010 -0700
@@ -1,5 +1,5 @@
/*
- * Copyright (c) 2007, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2007, 2010, Oracle and/or its affiliates. All rights reserved.
* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
*
* This code is free software; you can redistribute it and/or modify it
@@ -39,7 +39,7 @@
if (_generations == NULL)
vm_exit_during_initialization("Unable to allocate gen spec");
- if (UseParNewGC && ParallelGCThreads > 0) {
+ if (ParNewGeneration::in_use()) {
if (UseAdaptiveSizePolicy) {
_generations[0] = new GenerationSpec(Generation::ASParNew,
_initial_gen0_size, _max_gen0_size);
@@ -79,7 +79,7 @@
void ConcurrentMarkSweepPolicy::initialize_gc_policy_counters() {
// initialize the policy counters - 2 collectors, 3 generations
- if (UseParNewGC && ParallelGCThreads > 0) {
+ if (ParNewGeneration::in_use()) {
_gc_policy_counters = new GCPolicyCounters("ParNew:CMS", 2, 3);
}
else {
@@ -102,7 +102,7 @@
assert(size_policy() != NULL, "A size policy is required");
// initialize the policy counters - 2 collectors, 3 generations
- if (UseParNewGC && ParallelGCThreads > 0) {
+ if (ParNewGeneration::in_use()) {
_gc_policy_counters = new CMSGCAdaptivePolicyCounters("ParNew:CMS", 2, 3,
size_policy());
}
--- a/hotspot/src/share/vm/gc_implementation/concurrentMarkSweep/cmsPermGen.cpp Fri Oct 15 09:38:20 2010 +0200
+++ b/hotspot/src/share/vm/gc_implementation/concurrentMarkSweep/cmsPermGen.cpp Fri Oct 15 02:59:48 2010 -0700
@@ -1,5 +1,5 @@
/*
- * Copyright (c) 2007, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2007, 2010, Oracle and/or its affiliates. All rights reserved.
* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
*
* This code is free software; you can redistribute it and/or modify it
@@ -50,6 +50,18 @@
}
}
+HeapWord* CMSPermGen::request_expand_and_allocate(Generation* gen,
+ size_t size,
+ GCCause::Cause prev_cause /* ignored */) {
+ HeapWord* obj = gen->expand_and_allocate(size, false);
+ if (gen->capacity() >= _capacity_expansion_limit) {
+ set_capacity_expansion_limit(gen->capacity() + MaxPermHeapExpansion);
+ assert(((ConcurrentMarkSweepGeneration*)gen)->should_concurrent_collect(),
+ "Should kick off a collection if one not in progress");
+ }
+ return obj;
+}
+
void CMSPermGen::compute_new_size() {
_gen->compute_new_size();
}
--- a/hotspot/src/share/vm/gc_implementation/concurrentMarkSweep/cmsPermGen.hpp Fri Oct 15 09:38:20 2010 +0200
+++ b/hotspot/src/share/vm/gc_implementation/concurrentMarkSweep/cmsPermGen.hpp Fri Oct 15 02:59:48 2010 -0700
@@ -33,6 +33,10 @@
// The "generation" view.
ConcurrentMarkSweepGeneration* _gen;
+ // Override default implementation from PermGen
+ virtual HeapWord* request_expand_and_allocate(Generation* gen, size_t size,
+ GCCause::Cause prev_cause);
+
public:
CMSPermGen(ReservedSpace rs, size_t initial_byte_size,
CardTableRS* ct, FreeBlockDictionary::DictionaryChoice);
--- a/hotspot/src/share/vm/gc_implementation/concurrentMarkSweep/compactibleFreeListSpace.cpp Fri Oct 15 09:38:20 2010 +0200
+++ b/hotspot/src/share/vm/gc_implementation/concurrentMarkSweep/compactibleFreeListSpace.cpp Fri Oct 15 02:59:48 2010 -0700
@@ -124,7 +124,8 @@
checkFreeListConsistency();
// Initialize locks for parallel case.
- if (ParallelGCThreads > 0) {
+
+ if (CollectedHeap::use_parallel_gc_threads()) {
for (size_t i = IndexSetStart; i < IndexSetSize; i += IndexSetStride) {
_indexedFreeListParLocks[i] = new Mutex(Mutex::leaf - 1, // == ExpandHeap_lock - 1
"a freelist par lock",
@@ -1071,7 +1072,8 @@
// at address below "p" in finding the object that contains "p"
// and those objects (if garbage) may have been modified to hold
// live range information.
- // assert(ParallelGCThreads > 0 || _bt.block_start(p) == p, "Should be a block boundary");
+ // assert(CollectedHeap::use_parallel_gc_threads() || _bt.block_start(p) == p,
+ // "Should be a block boundary");
if (FreeChunk::indicatesFreeChunk(p)) return false;
klassOop k = oop(p)->klass_or_null();
if (k != NULL) {
@@ -2932,7 +2934,9 @@
"n_tasks calculation incorrect");
SequentialSubTasksDone* pst = conc_par_seq_tasks();
assert(!pst->valid(), "Clobbering existing data?");
- pst->set_par_threads(n_threads);
+ // Sets the condition for completion of the subtask (how many threads
+ // need to finish in order to be done).
+ pst->set_n_threads(n_threads);
pst->set_n_tasks((int)n_tasks);
}
@@ -2972,6 +2976,8 @@
"n_tasks calculation incorrect");
SequentialSubTasksDone* pst = conc_par_seq_tasks();
assert(!pst->valid(), "Clobbering existing data?");
- pst->set_par_threads(n_threads);
+ // Sets the condition for completion of the subtask (how many threads
+ // need to finish in order to be done).
+ pst->set_n_threads(n_threads);
pst->set_n_tasks((int)n_tasks);
}
--- a/hotspot/src/share/vm/gc_implementation/concurrentMarkSweep/concurrentMarkSweepGeneration.cpp Fri Oct 15 09:38:20 2010 +0200
+++ b/hotspot/src/share/vm/gc_implementation/concurrentMarkSweep/concurrentMarkSweepGeneration.cpp Fri Oct 15 02:59:48 2010 -0700
@@ -195,7 +195,7 @@
"Offset of FreeChunk::_prev within FreeChunk must match"
" that of OopDesc::_klass within OopDesc");
)
- if (ParallelGCThreads > 0) {
+ if (CollectedHeap::use_parallel_gc_threads()) {
typedef CMSParGCThreadState* CMSParGCThreadStatePtr;
_par_gc_thread_states =
NEW_C_HEAP_ARRAY(CMSParGCThreadStatePtr, ParallelGCThreads);
@@ -540,8 +540,6 @@
_is_alive_closure(_span, &_markBitMap),
_restart_addr(NULL),
_overflow_list(NULL),
- _preserved_oop_stack(NULL),
- _preserved_mark_stack(NULL),
_stats(cmsGen),
_eden_chunk_array(NULL), // may be set in ctor body
_eden_chunk_capacity(0), // -- ditto --
@@ -616,7 +614,7 @@
}
// Support for multi-threaded concurrent phases
- if (ParallelGCThreads > 0 && CMSConcurrentMTEnabled) {
+ if (CollectedHeap::use_parallel_gc_threads() && CMSConcurrentMTEnabled) {
if (FLAG_IS_DEFAULT(ConcGCThreads)) {
// just for now
FLAG_SET_DEFAULT(ConcGCThreads, (ParallelGCThreads + 3)/4);
@@ -628,6 +626,8 @@
warning("GC/CMS: _conc_workers allocation failure: "
"forcing -CMSConcurrentMTEnabled");
CMSConcurrentMTEnabled = false;
+ } else {
+ _conc_workers->initialize_workers();
}
} else {
CMSConcurrentMTEnabled = false;
@@ -936,7 +936,7 @@
// along with all the other pointers into the heap but
// compaction is expected to be a rare event with
// a heap using cms so don't do it without seeing the need.
- if (ParallelGCThreads > 0) {
+ if (CollectedHeap::use_parallel_gc_threads()) {
for (uint i = 0; i < ParallelGCThreads; i++) {
_par_gc_thread_states[i]->promo.reset();
}
@@ -2630,7 +2630,8 @@
// Should call gc_prologue_work() for all cms gens we are responsible for
bool registerClosure = _collectorState >= Marking
&& _collectorState < Sweeping;
- ModUnionClosure* muc = ParallelGCThreads > 0 ? &_modUnionClosurePar
+ ModUnionClosure* muc = CollectedHeap::use_parallel_gc_threads() ?
+ &_modUnionClosurePar
: &_modUnionClosure;
_cmsGen->gc_prologue_work(full, registerClosure, muc);
_permGen->gc_prologue_work(full, registerClosure, muc);
@@ -2731,7 +2732,7 @@
collector()->gc_epilogue(full);
// Also reset promotion tracking in par gc thread states.
- if (ParallelGCThreads > 0) {
+ if (CollectedHeap::use_parallel_gc_threads()) {
for (uint i = 0; i < ParallelGCThreads; i++) {
_par_gc_thread_states[i]->promo.stopTrackingPromotions(i);
}
@@ -3263,6 +3264,7 @@
ConcurrentMarkSweepGeneration::expand_and_allocate(size_t word_size,
bool tlab,
bool parallel) {
+ CMSSynchronousYieldRequest yr;
assert(!tlab, "Can't deal with TLAB allocation");
MutexLockerEx x(freelistLock(), Mutex::_no_safepoint_check_flag);
expand(word_size*HeapWordSize, MinHeapDeltaBytes,
@@ -3709,20 +3711,26 @@
class CMSConcMarkingTerminator: public ParallelTaskTerminator {
CMSCollector* _collector;
CMSConcMarkingTask* _task;
- bool _yield;
- protected:
+ public:
virtual void yield();
- public:
+
// "n_threads" is the number of threads to be terminated.
// "queue_set" is a set of work queues of other threads.
// "collector" is the CMS collector associated with this task terminator.
// "yield" indicates whether we need the gang as a whole to yield.
- CMSConcMarkingTerminator(int n_threads, TaskQueueSetSuper* queue_set,
- CMSCollector* collector, bool yield) :
+ CMSConcMarkingTerminator(int n_threads, TaskQueueSetSuper* queue_set, CMSCollector* collector) :
ParallelTaskTerminator(n_threads, queue_set),
- _collector(collector),
- _yield(yield) { }
-
+ _collector(collector) { }
+
+ void set_task(CMSConcMarkingTask* task) {
+ _task = task;
+ }
+};
+
+class CMSConcMarkingTerminatorTerminator: public TerminatorTerminator {
+ CMSConcMarkingTask* _task;
+ public:
+ bool should_exit_termination();
void set_task(CMSConcMarkingTask* task) {
_task = task;
}
@@ -3731,13 +3739,14 @@
// MT Concurrent Marking Task
class CMSConcMarkingTask: public YieldingFlexibleGangTask {
CMSCollector* _collector;
- YieldingFlexibleWorkGang* _workers; // the whole gang
int _n_workers; // requested/desired # workers
bool _asynch;
bool _result;
CompactibleFreeListSpace* _cms_space;
CompactibleFreeListSpace* _perm_space;
- HeapWord* _global_finger;
+ char _pad_front[64]; // padding to ...
+ HeapWord* _global_finger; // ... avoid sharing cache line
+ char _pad_back[64];
HeapWord* _restart_addr;
// Exposed here for yielding support
@@ -3745,28 +3754,30 @@
// The per thread work queues, available here for stealing
OopTaskQueueSet* _task_queues;
+
+ // Termination (and yielding) support
CMSConcMarkingTerminator _term;
+ CMSConcMarkingTerminatorTerminator _term_term;
public:
CMSConcMarkingTask(CMSCollector* collector,
CompactibleFreeListSpace* cms_space,
CompactibleFreeListSpace* perm_space,
- bool asynch, int n_workers,
+ bool asynch,
YieldingFlexibleWorkGang* workers,
OopTaskQueueSet* task_queues):
YieldingFlexibleGangTask("Concurrent marking done multi-threaded"),
_collector(collector),
_cms_space(cms_space),
_perm_space(perm_space),
- _asynch(asynch), _n_workers(n_workers), _result(true),
- _workers(workers), _task_queues(task_queues),
- _term(n_workers, task_queues, _collector, asynch),
+ _asynch(asynch), _n_workers(0), _result(true),
+ _task_queues(task_queues),
+ _term(_n_workers, task_queues, _collector),
_bit_map_lock(collector->bitMapLock())
{
- assert(n_workers <= workers->total_workers(),
- "Else termination won't work correctly today"); // XXX FIX ME!
- _requested_size = n_workers;
+ _requested_size = _n_workers;
_term.set_task(this);
+ _term_term.set_task(this);
assert(_cms_space->bottom() < _perm_space->bottom(),
"Finger incorrectly initialized below");
_restart_addr = _global_finger = _cms_space->bottom();
@@ -3781,7 +3792,16 @@
CMSConcMarkingTerminator* terminator() { return &_term; }
+ virtual void set_for_termination(int active_workers) {
+ terminator()->reset_for_reuse(active_workers);
+ }
+
void work(int i);
+ bool should_yield() {
+ return ConcurrentMarkSweepThread::should_yield()
+ && !_collector->foregroundGCIsActive()
+ && _asynch;
+ }
virtual void coordinator_yield(); // stuff done by coordinator
bool result() { return _result; }
@@ -3803,10 +3823,17 @@
void bump_global_finger(HeapWord* f);
};
+bool CMSConcMarkingTerminatorTerminator::should_exit_termination() {
+ assert(_task != NULL, "Error");
+ return _task->yielding();
+ // Note that we do not need the disjunct || _task->should_yield() above
+ // because we want terminating threads to yield only if the task
+ // is already in the midst of yielding, which happens only after at least one
+ // thread has yielded.
+}
+
void CMSConcMarkingTerminator::yield() {
- if (ConcurrentMarkSweepThread::should_yield() &&
- !_collector->foregroundGCIsActive() &&
- _yield) {
+ if (_task->should_yield()) {
_task->yield();
} else {
ParallelTaskTerminator::yield();
@@ -4031,6 +4058,7 @@
class Par_ConcMarkingClosure: public Par_KlassRememberingOopClosure {
private:
+ CMSConcMarkingTask* _task;
MemRegion _span;
CMSBitMap* _bit_map;
CMSMarkStack* _overflow_stack;
@@ -4038,11 +4066,12 @@
protected:
DO_OOP_WORK_DEFN
public:
- Par_ConcMarkingClosure(CMSCollector* collector, OopTaskQueue* work_queue,
+ Par_ConcMarkingClosure(CMSCollector* collector, CMSConcMarkingTask* task, OopTaskQueue* work_queue,
CMSBitMap* bit_map, CMSMarkStack* overflow_stack,
CMSMarkStack* revisit_stack):
Par_KlassRememberingOopClosure(collector, NULL, revisit_stack),
- _span(_collector->_span),
+ _task(task),
+ _span(collector->_span),
_work_queue(work_queue),
_bit_map(bit_map),
_overflow_stack(overflow_stack)
@@ -4051,6 +4080,11 @@
virtual void do_oop(narrowOop* p);
void trim_queue(size_t max);
void handle_stack_overflow(HeapWord* lost);
+ void do_yield_check() {
+ if (_task->should_yield()) {
+ _task->yield();
+ }
+ }
};
// Grey object scanning during work stealing phase --
@@ -4094,6 +4128,7 @@
handle_stack_overflow(addr);
}
} // Else, some other thread got there first
+ do_yield_check();
}
}
@@ -4109,6 +4144,7 @@
assert(_span.contains((HeapWord*)new_oop), "Not in span");
assert(new_oop->is_parsable(), "Should be parsable");
new_oop->oop_iterate(this); // do_oop() above
+ do_yield_check();
}
}
}
@@ -4136,7 +4172,7 @@
CMSMarkStack* ovflw = &(_collector->_markStack);
CMSMarkStack* revisit = &(_collector->_revisitStack);
int* seed = _collector->hash_seed(i);
- Par_ConcMarkingClosure cl(_collector, work_q, bm, ovflw, revisit);
+ Par_ConcMarkingClosure cl(_collector, this, work_q, bm, ovflw, revisit);
while (true) {
cl.trim_queue(0);
assert(work_q->size() == 0, "Should have been emptied above");
@@ -4149,9 +4185,11 @@
assert(obj_to_scan->is_oop(), "Should be an oop");
assert(bm->isMarked((HeapWord*)obj_to_scan), "Grey object");
obj_to_scan->oop_iterate(&cl);
- } else if (terminator()->offer_termination()) {
+ } else if (terminator()->offer_termination(&_term_term)) {
assert(work_q->size() == 0, "Impossible!");
break;
+ } else if (yielding() || should_yield()) {
+ yield();
}
}
}
@@ -4220,9 +4258,12 @@
CompactibleFreeListSpace* cms_space = _cmsGen->cmsSpace();
CompactibleFreeListSpace* perm_space = _permGen->cmsSpace();
- CMSConcMarkingTask tsk(this, cms_space, perm_space,
- asynch, num_workers /* number requested XXX */,
- conc_workers(), task_queues());
+ CMSConcMarkingTask tsk(this,
+ cms_space,
+ perm_space,
+ asynch,
+ conc_workers(),
+ task_queues());
// Since the actual number of workers we get may be different
// from the number we requested above, do we need to do anything different
@@ -4326,6 +4367,10 @@
verify_overflow_empty();
_abort_preclean = false;
if (CMSPrecleaningEnabled) {
+ // Precleaning is currently not MT but the reference processor
+ // may be set for MT. Disable it temporarily here.
+ ReferenceProcessor* rp = ref_processor();
+ ReferenceProcessorMTProcMutator z(rp, false);
_eden_chunk_index = 0;
size_t used = get_eden_used();
size_t capacity = get_eden_capacity();
@@ -4918,7 +4963,7 @@
// dirtied since the first checkpoint in this GC cycle and prior to
// the most recent young generation GC, minus those cleaned up by the
// concurrent precleaning.
- if (CMSParallelRemarkEnabled && ParallelGCThreads > 0) {
+ if (CMSParallelRemarkEnabled && CollectedHeap::use_parallel_gc_threads()) {
TraceTime t("Rescan (parallel) ", PrintGCDetails, false, gclog_or_tty);
do_remark_parallel();
} else {
@@ -5012,7 +5057,6 @@
// Parallel remark task
class CMSParRemarkTask: public AbstractGangTask {
CMSCollector* _collector;
- WorkGang* _workers;
int _n_workers;
CompactibleFreeListSpace* _cms_space;
CompactibleFreeListSpace* _perm_space;
@@ -5025,21 +5069,21 @@
CMSParRemarkTask(CMSCollector* collector,
CompactibleFreeListSpace* cms_space,
CompactibleFreeListSpace* perm_space,
- int n_workers, WorkGang* workers,
+ int n_workers, FlexibleWorkGang* workers,
OopTaskQueueSet* task_queues):
AbstractGangTask("Rescan roots and grey objects in parallel"),
_collector(collector),
_cms_space(cms_space), _perm_space(perm_space),
_n_workers(n_workers),
- _workers(workers),
_task_queues(task_queues),
- _term(workers->total_workers(), task_queues) { }
+ _term(n_workers, task_queues) { }
OopTaskQueueSet* task_queues() { return _task_queues; }
OopTaskQueue* work_queue(int i) { return task_queues()->queue(i); }
ParallelTaskTerminator* terminator() { return &_term; }
+ int n_workers() { return _n_workers; }
void work(int i);
@@ -5057,6 +5101,11 @@
void do_work_steal(int i, Par_MarkRefsIntoAndScanClosure* cl, int* seed);
};
+// work_queue(i) is passed to the closure
+// Par_MarkRefsIntoAndScanClosure. The "i" parameter
+// also is passed to do_dirty_card_rescan_tasks() and to
+// do_work_steal() to select the i-th task_queue.
+
void CMSParRemarkTask::work(int i) {
elapsedTimer _timer;
ResourceMark rm;
@@ -5128,6 +5177,7 @@
// Do the rescan tasks for each of the two spaces
// (cms_space and perm_space) in turn.
+ // "i" is passed to select the "i-th" task_queue
do_dirty_card_rescan_tasks(_cms_space, i, &par_mrias_cl);
do_dirty_card_rescan_tasks(_perm_space, i, &par_mrias_cl);
_timer.stop();
@@ -5150,6 +5200,7 @@
}
}
+// Note that parameter "i" is not used.
void
CMSParRemarkTask::do_young_space_rescan(int i,
Par_MarkRefsIntoAndScanClosure* cl, ContiguousSpace* space,
@@ -5309,8 +5360,13 @@
size_t num_from_overflow_list = MIN2((size_t)(work_q->max_elems() - work_q->size())/4,
(size_t)ParGCDesiredObjsFromOverflowList);
// Now check if there's any work in the overflow list
+ // Passing ParallelGCThreads as the third parameter, no_of_gc_threads,
+ // only affects the number of attempts made to get work from the
+ // overflow list and does not affect the number of workers. Just
+ // pass ParallelGCThreads so this behavior is unchanged.
if (_collector->par_take_from_overflow_list(num_from_overflow_list,
- work_q)) {
+ work_q,
+ ParallelGCThreads)) {
// found something in global overflow list;
// not yet ready to go stealing work from others.
// We'd like to assert(work_q->size() != 0, ...)
@@ -5367,11 +5423,12 @@
// Merge the per-thread plab arrays into the global survivor chunk
// array which will provide the partitioning of the survivor space
// for CMS rescan.
-void CMSCollector::merge_survivor_plab_arrays(ContiguousSpace* surv) {
+void CMSCollector::merge_survivor_plab_arrays(ContiguousSpace* surv,
+ int no_of_gc_threads) {
assert(_survivor_plab_array != NULL, "Error");
assert(_survivor_chunk_array != NULL, "Error");
assert(_collectorState == FinalMarking, "Error");
- for (uint j = 0; j < ParallelGCThreads; j++) {
+ for (int j = 0; j < no_of_gc_threads; j++) {
_cursor[j] = 0;
}
HeapWord* top = surv->top();
@@ -5379,7 +5436,7 @@
for (i = 0; i < _survivor_chunk_capacity; i++) { // all sca entries
HeapWord* min_val = top; // Higher than any PLAB address
uint min_tid = 0; // position of min_val this round
- for (uint j = 0; j < ParallelGCThreads; j++) {
+ for (int j = 0; j < no_of_gc_threads; j++) {
ChunkArray* cur_sca = &_survivor_plab_array[j];
if (_cursor[j] == cur_sca->end()) {
continue;
@@ -5413,7 +5470,7 @@
// Verify that we used up all the recorded entries
#ifdef ASSERT
size_t total = 0;
- for (uint j = 0; j < ParallelGCThreads; j++) {
+ for (int j = 0; j < no_of_gc_threads; j++) {
assert(_cursor[j] == _survivor_plab_array[j].end(), "Ctl pt invariant");
total += _cursor[j];
}
@@ -5448,13 +5505,15 @@
// Each valid entry in [0, _eden_chunk_index) represents a task.
size_t n_tasks = _eden_chunk_index + 1;
assert(n_tasks == 1 || _eden_chunk_array != NULL, "Error");
- pst->set_par_threads(n_threads);
+ // Sets the condition for completion of the subtask (how many threads
+ // need to finish in order to be done).
+ pst->set_n_threads(n_threads);
pst->set_n_tasks((int)n_tasks);
}
// Merge the survivor plab arrays into _survivor_chunk_array
if (_survivor_plab_array != NULL) {
- merge_survivor_plab_arrays(dng->from());
+ merge_survivor_plab_arrays(dng->from(), n_threads);
} else {
assert(_survivor_chunk_index == 0, "Error");
}
@@ -5463,7 +5522,9 @@
{
SequentialSubTasksDone* pst = dng->to()->par_seq_tasks();
assert(!pst->valid(), "Clobbering existing data?");
- pst->set_par_threads(n_threads);
+ // Sets the condition for completion of the subtask (how many threads
+ // need to finish in order to be done).
+ pst->set_n_threads(n_threads);
pst->set_n_tasks(1);
assert(pst->valid(), "Error");
}
@@ -5474,7 +5535,9 @@
assert(!pst->valid(), "Clobbering existing data?");
size_t n_tasks = _survivor_chunk_index + 1;
assert(n_tasks == 1 || _survivor_chunk_array != NULL, "Error");
- pst->set_par_threads(n_threads);
+ // Sets the condition for completion of the subtask (how many threads
+ // need to finish in order to be done).
+ pst->set_n_threads(n_threads);
pst->set_n_tasks((int)n_tasks);
assert(pst->valid(), "Error");
}
@@ -5483,7 +5546,7 @@
// Parallel version of remark
void CMSCollector::do_remark_parallel() {
GenCollectedHeap* gch = GenCollectedHeap::heap();
- WorkGang* workers = gch->workers();
+ FlexibleWorkGang* workers = gch->workers();
assert(workers != NULL, "Need parallel worker threads.");
int n_workers = workers->total_workers();
CompactibleFreeListSpace* cms_space = _cmsGen->cmsSpace();
@@ -5636,13 +5699,11 @@
////////////////////////////////////////////////////////
// Parallel Reference Processing Task Proxy Class
////////////////////////////////////////////////////////
-class CMSRefProcTaskProxy: public AbstractGangTask {
+class CMSRefProcTaskProxy: public AbstractGangTaskWOopQueues {
typedef AbstractRefProcTaskExecutor::ProcessTask ProcessTask;
CMSCollector* _collector;
CMSBitMap* _mark_bit_map;
const MemRegion _span;
- OopTaskQueueSet* _task_queues;
- ParallelTaskTerminator _term;
ProcessTask& _task;
public:
@@ -5650,24 +5711,21 @@
CMSCollector* collector,
const MemRegion& span,
CMSBitMap* mark_bit_map,
- int total_workers,
+ AbstractWorkGang* workers,
OopTaskQueueSet* task_queues):
- AbstractGangTask("Process referents by policy in parallel"),
+ AbstractGangTaskWOopQueues("Process referents by policy in parallel",
+ task_queues),
_task(task),
- _collector(collector), _span(span), _mark_bit_map(mark_bit_map),
- _task_queues(task_queues),
- _term(total_workers, task_queues)
+ _collector(collector), _span(span), _mark_bit_map(mark_bit_map)
{
assert(_collector->_span.equals(_span) && !_span.is_empty(),
"Inconsistency in _span");
}
- OopTaskQueueSet* task_queues() { return _task_queues; }
+ OopTaskQueueSet* task_queues() { return queues(); }
OopTaskQueue* work_queue(int i) { return task_queues()->queue(i); }
- ParallelTaskTerminator* terminator() { return &_term; }
-
void do_work_steal(int i,
CMSParDrainMarkingStackClosure* drain,
CMSParKeepAliveClosure* keep_alive,
@@ -5739,8 +5797,13 @@
size_t num_from_overflow_list = MIN2((size_t)(work_q->max_elems() - work_q->size())/4,
(size_t)ParGCDesiredObjsFromOverflowList);
// Now check if there's any work in the overflow list
+ // Passing ParallelGCThreads as the third parameter, no_of_gc_threads,
+ // only affects the number of attempts made to get work from the
+ // overflow list and does not affect the number of workers. Just
+ // pass ParallelGCThreads so this behavior is unchanged.
if (_collector->par_take_from_overflow_list(num_from_overflow_list,
- work_q)) {
+ work_q,
+ ParallelGCThreads)) {
// Found something in global overflow list;
// not yet ready to go stealing work from others.
// We'd like to assert(work_q->size() != 0, ...)
@@ -5773,13 +5836,12 @@
void CMSRefProcTaskExecutor::execute(ProcessTask& task)
{
GenCollectedHeap* gch = GenCollectedHeap::heap();
- WorkGang* workers = gch->workers();
+ FlexibleWorkGang* workers = gch->workers();
assert(workers != NULL, "Need parallel worker threads.");
- int n_workers = workers->total_workers();
CMSRefProcTaskProxy rp_task(task, &_collector,
_collector.ref_processor()->span(),
_collector.markBitMap(),
- n_workers, _collector.task_queues());
+ workers, _collector.task_queues());
workers->run_task(&rp_task);
}
@@ -5787,7 +5849,7 @@
{
GenCollectedHeap* gch = GenCollectedHeap::heap();
- WorkGang* workers = gch->workers();
+ FlexibleWorkGang* workers = gch->workers();
assert(workers != NULL, "Need parallel worker threads.");
CMSRefEnqueueTaskProxy enq_task(task);
workers->run_task(&enq_task);
@@ -5814,6 +5876,14 @@
{
TraceTime t("weak refs processing", PrintGCDetails, false, gclog_or_tty);
if (rp->processing_is_mt()) {
+ // Set the degree of MT here. If the discovery is done MT, there
+ // may have been a different number of threads doing the discovery
+ // and a different number of discovered lists may have Ref objects.
+ // That is OK as long as the Reference lists are balanced (see
+ // balance_all_queues() and balance_queues()).
+
+
+ rp->set_mt_degree(ParallelGCThreads);
CMSRefProcTaskExecutor task_executor(*this);
rp->process_discovered_references(&_is_alive_closure,
&cmsKeepAliveClosure,
@@ -5874,6 +5944,7 @@
rp->set_enqueuing_is_done(true);
if (rp->processing_is_mt()) {
+ rp->balance_all_queues();
CMSRefProcTaskExecutor task_executor(*this);
rp->enqueue_discovered_references(&task_executor);
} else {
@@ -8708,7 +8779,8 @@
// similar changes might be needed.
// CR 6797058 has been filed to consolidate the common code.
bool CMSCollector::par_take_from_overflow_list(size_t num,
- OopTaskQueue* work_q) {
+ OopTaskQueue* work_q,
+ int no_of_gc_threads) {
assert(work_q->size() == 0, "First empty local work queue");
assert(num < work_q->max_elems(), "Can't bite more than we can chew");
if (_overflow_list == NULL) {
@@ -8717,7 +8789,9 @@
// Grab the entire list; we'll put back a suffix
oop prefix = (oop)Atomic::xchg_ptr(BUSY, &_overflow_list);
Thread* tid = Thread::current();
- size_t CMSOverflowSpinCount = (size_t)ParallelGCThreads;
+ // Before "no_of_gc_threads" was introduced CMSOverflowSpinCount was
+ // set to ParallelGCThreads.
+ size_t CMSOverflowSpinCount = (size_t) no_of_gc_threads; // was ParallelGCThreads;
size_t sleep_time_millis = MAX2((size_t)1, num/100);
// If the list is busy, we spin for a short while,
// sleeping between attempts to get the list.
@@ -8867,23 +8941,10 @@
// failures where possible, thus, incrementally hardening the VM
// in such low resource situations.
void CMSCollector::preserve_mark_work(oop p, markOop m) {
- if (_preserved_oop_stack == NULL) {
- assert(_preserved_mark_stack == NULL,
- "bijection with preserved_oop_stack");
- // Allocate the stacks
- _preserved_oop_stack = new (ResourceObj::C_HEAP)
- GrowableArray<oop>(PreserveMarkStackSize, true);
- _preserved_mark_stack = new (ResourceObj::C_HEAP)
- GrowableArray<markOop>(PreserveMarkStackSize, true);
- if (_preserved_oop_stack == NULL || _preserved_mark_stack == NULL) {
- vm_exit_out_of_memory(2* PreserveMarkStackSize * sizeof(oop) /* punt */,
- "Preserved Mark/Oop Stack for CMS (C-heap)");
- }
- }
- _preserved_oop_stack->push(p);
- _preserved_mark_stack->push(m);
+ _preserved_oop_stack.push(p);
+ _preserved_mark_stack.push(m);
assert(m == p->mark(), "Mark word changed");
- assert(_preserved_oop_stack->length() == _preserved_mark_stack->length(),
+ assert(_preserved_oop_stack.size() == _preserved_mark_stack.size(),
"bijection");
}
@@ -8925,42 +8986,30 @@
// effect on performance so great that this will
// likely just be in the noise anyway.
void CMSCollector::restore_preserved_marks_if_any() {
- if (_preserved_oop_stack == NULL) {
- assert(_preserved_mark_stack == NULL,
- "bijection with preserved_oop_stack");
- return;
- }
-
assert(SafepointSynchronize::is_at_safepoint(),
"world should be stopped");
assert(Thread::current()->is_ConcurrentGC_thread() ||
Thread::current()->is_VM_thread(),
"should be single-threaded");
-
- int length = _preserved_oop_stack->length();
- assert(_preserved_mark_stack->length() == length, "bijection");
- for (int i = 0; i < length; i++) {
- oop p = _preserved_oop_stack->at(i);
+ assert(_preserved_oop_stack.size() == _preserved_mark_stack.size(),
+ "bijection");
+
+ while (!_preserved_oop_stack.is_empty()) {
+ oop p = _preserved_oop_stack.pop();
assert(p->is_oop(), "Should be an oop");
assert(_span.contains(p), "oop should be in _span");
assert(p->mark() == markOopDesc::prototype(),
"Set when taken from overflow list");
- markOop m = _preserved_mark_stack->at(i);
+ markOop m = _preserved_mark_stack.pop();
p->set_mark(m);
}
- _preserved_mark_stack->clear();
- _preserved_oop_stack->clear();
- assert(_preserved_mark_stack->is_empty() &&
- _preserved_oop_stack->is_empty(),
+ assert(_preserved_mark_stack.is_empty() && _preserved_oop_stack.is_empty(),
"stacks were cleared above");
}
#ifndef PRODUCT
bool CMSCollector::no_preserved_marks() const {
- return ( ( _preserved_mark_stack == NULL
- && _preserved_oop_stack == NULL)
- || ( _preserved_mark_stack->is_empty()
- && _preserved_oop_stack->is_empty()));
+ return _preserved_mark_stack.is_empty() && _preserved_oop_stack.is_empty();
}
#endif
@@ -9256,4 +9305,3 @@
true /* recordGCEndTime */,
true /* countCollection */ );
}
-
--- a/hotspot/src/share/vm/gc_implementation/concurrentMarkSweep/concurrentMarkSweepGeneration.hpp Fri Oct 15 09:38:20 2010 +0200
+++ b/hotspot/src/share/vm/gc_implementation/concurrentMarkSweep/concurrentMarkSweepGeneration.hpp Fri Oct 15 02:59:48 2010 -0700
@@ -537,8 +537,8 @@
// The following array-pair keeps track of mark words
// displaced for accomodating overflow list above.
// This code will likely be revisited under RFE#4922830.
- GrowableArray<oop>* _preserved_oop_stack;
- GrowableArray<markOop>* _preserved_mark_stack;
+ Stack<oop> _preserved_oop_stack;
+ Stack<markOop> _preserved_mark_stack;
int* _hash_seed;
@@ -729,7 +729,9 @@
// Support for marking stack overflow handling
bool take_from_overflow_list(size_t num, CMSMarkStack* to_stack);
- bool par_take_from_overflow_list(size_t num, OopTaskQueue* to_work_q);
+ bool par_take_from_overflow_list(size_t num,
+ OopTaskQueue* to_work_q,
+ int no_of_gc_threads);
void push_on_overflow_list(oop p);
void par_push_on_overflow_list(oop p);
// the following is, obviously, not, in general, "MT-stable"
@@ -768,7 +770,7 @@
void abortable_preclean(); // Preclean while looking for possible abort
void initialize_sequential_subtasks_for_young_gen_rescan(int i);
// Helper function for above; merge-sorts the per-thread plab samples
- void merge_survivor_plab_arrays(ContiguousSpace* surv);
+ void merge_survivor_plab_arrays(ContiguousSpace* surv, int no_of_gc_threads);
// Resets (i.e. clears) the per-thread plab sample vectors
void reset_survivor_plab_arrays();
--- a/hotspot/src/share/vm/gc_implementation/concurrentMarkSweep/concurrentMarkSweepThread.hpp Fri Oct 15 09:38:20 2010 +0200
+++ b/hotspot/src/share/vm/gc_implementation/concurrentMarkSweep/concurrentMarkSweepThread.hpp Fri Oct 15 02:59:48 2010 -0700
@@ -1,5 +1,5 @@
/*
- * Copyright (c) 2001, 2006, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2001, 2010, Oracle and/or its affiliates. All rights reserved.
* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
*
* This code is free software; you can redistribute it and/or modify it
@@ -123,24 +123,44 @@
// or given timeout, whichever is earlier.
void wait_on_cms_lock(long t); // milliseconds
- // The CMS thread will yield during the work portion of it's cycle
+ // The CMS thread will yield during the work portion of its cycle
// only when requested to. Both synchronous and asychronous requests
- // are provided. A synchronous request is used for young gen
- // collections and direct allocations. The requesting thread increments
- // pending_yields at the beginning of an operation, and decrements it when
- // the operation is completed. The CMS thread yields when pending_yields
- // is positive. An asynchronous request is used by iCMS in the stop_icms()
- // operation. A single yield satisfies the outstanding asynch yield requests.
- // The requesting thread increments both pending_yields and pending_decrements.
- // After yielding, the CMS thread decrements both by the amount in
- // pending_decrements.
+ // are provided:
+ // (1) A synchronous request is used for young gen collections and
+ // for direct allocations. The requesting thread increments
+ // _pending_yields at the beginning of an operation, and decrements
+ // _pending_yields when that operation is completed.
+ // In turn, the CMS thread yields when _pending_yields is positive,
+ // and continues to yield until the value reverts to 0.
+ // (2) An asynchronous request, on the other hand, is used by iCMS
+ // for the stop_icms() operation. A single yield satisfies all of
+ // the outstanding asynch yield requests, of which there may
+ // occasionally be several in close succession. To accomplish
+ // this, an asynch-requesting thread atomically increments both
+ // _pending_yields and _pending_decrements. An asynchr requesting
+ // thread does not wait and "acknowledge" completion of an operation
+ // and deregister the request, like the synchronous version described
+ // above does. In turn, after yielding, the CMS thread decrements both
+ // _pending_yields and _pending_decrements by the value seen in
+ // _pending_decrements before the decrement.
+ // NOTE: The above scheme is isomorphic to having two request counters,
+ // one for async requests and one for sync requests, and for the CMS thread
+ // to check the sum of the two counters to decide whether it should yield
+ // and to clear only the async counter when it yields. However, it turns out
+ // to be more efficient for CMS code to just check a single counter
+ // _pending_yields that holds the sum (of both sync and async requests), and
+ // a second counter _pending_decrements that only holds the async requests,
+ // for greater efficiency, since in a typical CMS run, there are many more
+ // pontential (i.e. static) yield points than there are actual
+ // (i.e. dynamic) yields because of requests, which are few and far between.
+ //
// Note that, while "_pending_yields >= _pending_decrements" is an invariant,
// we cannot easily test that invariant, since the counters are manipulated via
// atomic instructions without explicit locking and we cannot read
// the two counters atomically together: one suggestion is to
// use (for example) 16-bit counters so as to be able to read the
// two counters atomically even on 32-bit platforms. Notice that
- // the second assert in acknowledge_yield_request() does indeed
+ // the second assert in acknowledge_yield_request() below does indeed
// check a form of the above invariant, albeit indirectly.
static void increment_pending_yields() {
@@ -152,6 +172,7 @@
assert(_pending_yields >= 0, "can't be negative");
}
static void asynchronous_yield_request() {
+ assert(CMSIncrementalMode, "Currently only used w/iCMS");
increment_pending_yields();
Atomic::inc(&_pending_decrements);
assert(_pending_decrements >= 0, "can't be negative");
@@ -159,6 +180,7 @@
static void acknowledge_yield_request() {
jint decrement = _pending_decrements;
if (decrement > 0) {
+ assert(CMSIncrementalMode, "Currently only used w/iCMS");
// Order important to preserve: _pending_yields >= _pending_decrements
Atomic::add(-decrement, &_pending_decrements);
Atomic::add(-decrement, &_pending_yields);
@@ -195,7 +217,7 @@
}
}
-// For scoped increment/decrement of yield requests
+// For scoped increment/decrement of (synchronous) yield requests
class CMSSynchronousYieldRequest: public StackObj {
public:
CMSSynchronousYieldRequest() {
--- a/hotspot/src/share/vm/gc_implementation/g1/concurrentMark.cpp Fri Oct 15 09:38:20 2010 +0200
+++ b/hotspot/src/share/vm/gc_implementation/g1/concurrentMark.cpp Fri Oct 15 02:59:48 2010 -0700
@@ -1,5 +1,5 @@
/*
- * Copyright (c) 2001, 2009, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2001, 2010, Oracle and/or its affiliates. All rights reserved.
* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
*
* This code is free software; you can redistribute it and/or modify it
@@ -278,15 +278,16 @@
if (_base != NULL) FREE_C_HEAP_ARRAY(oop, _base);
}
-void CMRegionStack::push(MemRegion mr) {
+void CMRegionStack::push_lock_free(MemRegion mr) {
assert(mr.word_size() > 0, "Precondition");
while (true) {
- if (isFull()) {
+ jint index = _index;
+
+ if (index >= _capacity) {
_overflow = true;
return;
}
// Otherwise...
- jint index = _index;
jint next_index = index+1;
jint res = Atomic::cmpxchg(next_index, &_index, index);
if (res == index) {
@@ -297,19 +298,17 @@
}
}
-// Currently we do not call this at all. Normally we would call it
-// during the concurrent marking / remark phases but we now call
-// the lock-based version instead. But we might want to resurrect this
-// code in the future. So, we'll leave it here commented out.
-#if 0
-MemRegion CMRegionStack::pop() {
+// Lock-free pop of the region stack. Called during the concurrent
+// marking / remark phases. Should only be called in tandem with
+// other lock-free pops.
+MemRegion CMRegionStack::pop_lock_free() {
while (true) {
- // Otherwise...
jint index = _index;
if (index == 0) {
return MemRegion();
}
+ // Otherwise...
jint next_index = index-1;
jint res = Atomic::cmpxchg(next_index, &_index, index);
if (res == index) {
@@ -326,7 +325,11 @@
// Otherwise, we need to try again.
}
}
-#endif // 0
+
+#if 0
+// The routines that manipulate the region stack with a lock are
+// not currently used. They should be retained, however, as a
+// diagnostic aid.
void CMRegionStack::push_with_lock(MemRegion mr) {
assert(mr.word_size() > 0, "Precondition");
@@ -361,6 +364,7 @@
}
}
}
+#endif
bool CMRegionStack::invalidate_entries_into_cset() {
bool result = false;
@@ -583,10 +587,13 @@
#endif
guarantee(parallel_marking_threads() > 0, "peace of mind");
- _parallel_workers = new WorkGang("G1 Parallel Marking Threads",
- (int) parallel_marking_threads(), false, true);
- if (_parallel_workers == NULL)
+ _parallel_workers = new FlexibleWorkGang("G1 Parallel Marking Threads",
+ (int) _parallel_marking_threads, false, true);
+ if (_parallel_workers == NULL) {
vm_exit_during_initialization("Failed necessary allocation.");
+ } else {
+ _parallel_workers->initialize_workers();
+ }
}
// so that the call below can read a sensible value
@@ -645,8 +652,9 @@
// We do reset all of them, since different phases will use
// different number of active threads. So, it's easiest to have all
// of them ready.
- for (int i = 0; i < (int) _max_task_num; ++i)
+ for (int i = 0; i < (int) _max_task_num; ++i) {
_tasks[i]->reset(_nextMarkBitMap);
+ }
// we need this to make sure that the flag is on during the evac
// pause with initial mark piggy-backed
@@ -985,7 +993,7 @@
"below the finger, pushing it",
mr.start(), mr.end());
- if (!region_stack_push(mr)) {
+ if (!region_stack_push_lock_free(mr)) {
if (verbose_low())
gclog_or_tty->print_cr("[global] region stack has overflown.");
}
@@ -1451,7 +1459,7 @@
_bm, _g1h->concurrent_mark(),
_region_bm, _card_bm);
calccl.no_yield();
- if (ParallelGCThreads > 0) {
+ if (G1CollectedHeap::use_parallel_gc_threads()) {
_g1h->heap_region_par_iterate_chunked(&calccl, i,
HeapRegion::FinalCountClaimValue);
} else {
@@ -1531,7 +1539,7 @@
G1NoteEndOfConcMarkClosure g1_note_end(_g1h,
&_par_cleanup_thread_state[i]->list,
i);
- if (ParallelGCThreads > 0) {
+ if (G1CollectedHeap::use_parallel_gc_threads()) {
_g1h->heap_region_par_iterate_chunked(&g1_note_end, i,
HeapRegion::NoteEndClaimValue);
} else {
@@ -1575,7 +1583,7 @@
{}
void work(int i) {
- if (ParallelGCThreads > 0) {
+ if (G1CollectedHeap::use_parallel_gc_threads()) {
_g1rs->scrub_par(_region_bm, _card_bm, i,
HeapRegion::ScrubRemSetClaimValue);
} else {
@@ -1647,7 +1655,7 @@
// Do counting once more with the world stopped for good measure.
G1ParFinalCountTask g1_par_count_task(g1h, nextMarkBitMap(),
&_region_bm, &_card_bm);
- if (ParallelGCThreads > 0) {
+ if (G1CollectedHeap::use_parallel_gc_threads()) {
assert(g1h->check_heap_region_claim_values(
HeapRegion::InitialClaimValue),
"sanity check");
@@ -1695,7 +1703,7 @@
// Note end of marking in all heap regions.
double note_end_start = os::elapsedTime();
G1ParNoteEndTask g1_par_note_end_task(g1h, _par_cleanup_thread_state);
- if (ParallelGCThreads > 0) {
+ if (G1CollectedHeap::use_parallel_gc_threads()) {
int n_workers = g1h->workers()->total_workers();
g1h->set_par_threads(n_workers);
g1h->workers()->run_task(&g1_par_note_end_task);
@@ -1720,7 +1728,7 @@
if (G1ScrubRemSets) {
double rs_scrub_start = os::elapsedTime();
G1ParScrubRemSetTask g1_par_scrub_rs_task(g1h, &_region_bm, &_card_bm);
- if (ParallelGCThreads > 0) {
+ if (G1CollectedHeap::use_parallel_gc_threads()) {
int n_workers = g1h->workers()->total_workers();
g1h->set_par_threads(n_workers);
g1h->workers()->run_task(&g1_par_scrub_rs_task);
@@ -1934,7 +1942,7 @@
g1h->ensure_parsability(false);
- if (ParallelGCThreads > 0) {
+ if (G1CollectedHeap::use_parallel_gc_threads()) {
G1CollectedHeap::StrongRootsScope srs(g1h);
// this is remark, so we'll use up all available threads
int active_workers = ParallelGCThreads;
@@ -2330,6 +2338,39 @@
return NULL;
}
+bool ConcurrentMark::invalidate_aborted_regions_in_cset() {
+ bool result = false;
+ for (int i = 0; i < (int)_max_task_num; ++i) {
+ CMTask* the_task = _tasks[i];
+ MemRegion mr = the_task->aborted_region();
+ if (mr.start() != NULL) {
+ assert(mr.end() != NULL, "invariant");
+ assert(mr.word_size() > 0, "invariant");
+ HeapRegion* hr = _g1h->heap_region_containing(mr.start());
+ assert(hr != NULL, "invariant");
+ if (hr->in_collection_set()) {
+ // The region points into the collection set
+ the_task->set_aborted_region(MemRegion());
+ result = true;
+ }
+ }
+ }
+ return result;
+}
+
+bool ConcurrentMark::has_aborted_regions() {
+ for (int i = 0; i < (int)_max_task_num; ++i) {
+ CMTask* the_task = _tasks[i];
+ MemRegion mr = the_task->aborted_region();
+ if (mr.start() != NULL) {
+ assert(mr.end() != NULL, "invariant");
+ assert(mr.word_size() > 0, "invariant");
+ return true;
+ }
+ }
+ return false;
+}
+
void ConcurrentMark::oops_do(OopClosure* cl) {
if (_markStack.size() > 0 && verbose_low())
gclog_or_tty->print_cr("[global] scanning the global marking stack, "
@@ -2348,13 +2389,22 @@
queue->oops_do(cl);
}
- // finally, invalidate any entries that in the region stack that
+ // Invalidate any entries, that are in the region stack, that
// point into the collection set
if (_regionStack.invalidate_entries_into_cset()) {
// otherwise, any gray objects copied during the evacuation pause
// might not be visited.
assert(_should_gray_objects, "invariant");
}
+
+ // Invalidate any aborted regions, recorded in the individual CM
+ // tasks, that point into the collection set.
+ if (invalidate_aborted_regions_in_cset()) {
+ // otherwise, any gray objects copied during the evacuation pause
+ // might not be visited.
+ assert(_should_gray_objects, "invariant");
+ }
+
}
void ConcurrentMark::clear_marking_state() {
@@ -2635,7 +2685,7 @@
// irrespective whether all collection set regions are below the
// finger, if the region stack is not empty. This is expected to be
// a rare case, so I don't think it's necessary to be smarted about it.
- if (!region_stack_empty())
+ if (!region_stack_empty() || has_aborted_regions())
_should_gray_objects = true;
}
@@ -2654,8 +2704,10 @@
_nextMarkBitMap->clearAll();
// Empty mark stack
clear_marking_state();
- for (int i = 0; i < (int)_max_task_num; ++i)
+ for (int i = 0; i < (int)_max_task_num; ++i) {
_tasks[i]->clear_region_fields();
+ _tasks[i]->clear_aborted_region();
+ }
_has_aborted = true;
SATBMarkQueueSet& satb_mq_set = JavaThread::satb_mark_queue_set();
@@ -2933,6 +2985,7 @@
_nextMarkBitMap = nextMarkBitMap;
clear_region_fields();
+ clear_aborted_region();
_calls = 0;
_elapsed_time_ms = 0.0;
@@ -3369,14 +3422,14 @@
CMObjectClosure oc(this);
SATBMarkQueueSet& satb_mq_set = JavaThread::satb_mark_queue_set();
- if (ParallelGCThreads > 0)
+ if (G1CollectedHeap::use_parallel_gc_threads())
satb_mq_set.set_par_closure(_task_id, &oc);
else
satb_mq_set.set_closure(&oc);
// This keeps claiming and applying the closure to completed buffers
// until we run out of buffers or we need to abort.
- if (ParallelGCThreads > 0) {
+ if (G1CollectedHeap::use_parallel_gc_threads()) {
while (!has_aborted() &&
satb_mq_set.par_apply_closure_to_completed_buffer(_task_id)) {
if (_cm->verbose_medium())
@@ -3396,7 +3449,7 @@
if (!concurrent() && !has_aborted()) {
// We should only do this during remark.
- if (ParallelGCThreads > 0)
+ if (G1CollectedHeap::use_parallel_gc_threads())
satb_mq_set.par_iterate_closure_all_threads(_task_id);
else
satb_mq_set.iterate_closure_all_threads();
@@ -3408,7 +3461,7 @@
concurrent() ||
satb_mq_set.completed_buffers_num() == 0, "invariant");
- if (ParallelGCThreads > 0)
+ if (G1CollectedHeap::use_parallel_gc_threads())
satb_mq_set.set_par_closure(_task_id, NULL);
else
satb_mq_set.set_closure(NULL);
@@ -3425,20 +3478,32 @@
assert(_region_finger == NULL,
"it should be NULL when we're not scanning a region");
- if (!_cm->region_stack_empty()) {
+ if (!_cm->region_stack_empty() || !_aborted_region.is_empty()) {
if (_cm->verbose_low())
gclog_or_tty->print_cr("[%d] draining region stack, size = %d",
_task_id, _cm->region_stack_size());
- MemRegion mr = _cm->region_stack_pop_with_lock();
- // it returns MemRegion() if the pop fails
- statsOnly(if (mr.start() != NULL) ++_region_stack_pops );
+ MemRegion mr;
+
+ if (!_aborted_region.is_empty()) {
+ mr = _aborted_region;
+ _aborted_region = MemRegion();
+
+ if (_cm->verbose_low())
+ gclog_or_tty->print_cr("[%d] scanning aborted region [ " PTR_FORMAT ", " PTR_FORMAT " )",
+ _task_id, mr.start(), mr.end());
+ } else {
+ mr = _cm->region_stack_pop_lock_free();
+ // it returns MemRegion() if the pop fails
+ statsOnly(if (mr.start() != NULL) ++_region_stack_pops );
+ }
while (mr.start() != NULL) {
if (_cm->verbose_medium())
gclog_or_tty->print_cr("[%d] we are scanning region "
"["PTR_FORMAT", "PTR_FORMAT")",
_task_id, mr.start(), mr.end());
+
assert(mr.end() <= _cm->finger(),
"otherwise the region shouldn't be on the stack");
assert(!mr.is_empty(), "Only non-empty regions live on the region stack");
@@ -3451,7 +3516,7 @@
if (has_aborted())
mr = MemRegion();
else {
- mr = _cm->region_stack_pop_with_lock();
+ mr = _cm->region_stack_pop_lock_free();
// it returns MemRegion() if the pop fails
statsOnly(if (mr.start() != NULL) ++_region_stack_pops );
}
@@ -3465,6 +3530,10 @@
// have definitely set _region_finger to something non-null.
assert(_region_finger != NULL, "invariant");
+ // Make sure that any previously aborted region has been
+ // cleared.
+ assert(_aborted_region.is_empty(), "aborted region not cleared");
+
// The iteration was actually aborted. So now _region_finger
// points to the address of the object we last scanned. If we
// leave it there, when we restart this task, we will rescan
@@ -3477,14 +3546,14 @@
if (!newRegion.is_empty()) {
if (_cm->verbose_low()) {
- gclog_or_tty->print_cr("[%d] pushing unscanned region"
- "[" PTR_FORMAT "," PTR_FORMAT ") on region stack",
+ gclog_or_tty->print_cr("[%d] recording unscanned region"
+ "[" PTR_FORMAT "," PTR_FORMAT ") in CMTask",
_task_id,
newRegion.start(), newRegion.end());
}
- // Now push the part of the region we didn't scan on the
- // region stack to make sure a task scans it later.
- _cm->region_stack_push_with_lock(newRegion);
+ // Now record the part of the region we didn't scan to
+ // make sure this task scans it later.
+ _aborted_region = newRegion;
}
// break from while
mr = MemRegion();
@@ -3654,6 +3723,8 @@
assert(concurrent() || _cm->region_stack_empty(),
"the region stack should have been cleared before remark");
+ assert(concurrent() || !_cm->has_aborted_regions(),
+ "aborted regions should have been cleared before remark");
assert(_region_finger == NULL,
"this should be non-null only when a region is being scanned");
@@ -3943,6 +4014,7 @@
// that, if a condition is false, we can immediately find out
// which one.
guarantee(_cm->out_of_regions(), "only way to reach here");
+ guarantee(_aborted_region.is_empty(), "only way to reach here");
guarantee(_cm->region_stack_empty(), "only way to reach here");
guarantee(_cm->mark_stack_empty(), "only way to reach here");
guarantee(_task_queue->size() == 0, "only way to reach here");
@@ -4042,7 +4114,8 @@
_nextMarkBitMap(NULL), _hash_seed(17),
_task_queue(task_queue),
_task_queues(task_queues),
- _oop_closure(NULL) {
+ _oop_closure(NULL),
+ _aborted_region(MemRegion()) {
guarantee(task_queue != NULL, "invariant");
guarantee(task_queues != NULL, "invariant");
--- a/hotspot/src/share/vm/gc_implementation/g1/concurrentMark.hpp Fri Oct 15 09:38:20 2010 +0200
+++ b/hotspot/src/share/vm/gc_implementation/g1/concurrentMark.hpp Fri Oct 15 02:59:48 2010 -0700
@@ -250,21 +250,23 @@
// This is lock-free; assumes that it will only be called in parallel
// with other "push" operations (no pops).
- void push(MemRegion mr);
-
-#if 0
- // This is currently not used. See the comment in the .cpp file.
+ void push_lock_free(MemRegion mr);
// Lock-free; assumes that it will only be called in parallel
// with other "pop" operations (no pushes).
- MemRegion pop();
-#endif // 0
+ MemRegion pop_lock_free();
+
+#if 0
+ // The routines that manipulate the region stack with a lock are
+ // not currently used. They should be retained, however, as a
+ // diagnostic aid.
// These two are the implementations that use a lock. They can be
// called concurrently with each other but they should not be called
// concurrently with the lock-free versions (push() / pop()).
void push_with_lock(MemRegion mr);
MemRegion pop_with_lock();
+#endif
bool isEmpty() { return _index == 0; }
bool isFull() { return _index == _capacity; }
@@ -398,6 +400,7 @@
volatile bool _concurrent;
// set at the end of a Full GC so that marking aborts
volatile bool _has_aborted;
+
// used when remark aborts due to an overflow to indicate that
// another concurrent marking phase should start
volatile bool _restart_for_overflow;
@@ -548,23 +551,30 @@
bool mark_stack_overflow() { return _markStack.overflow(); }
bool mark_stack_empty() { return _markStack.isEmpty(); }
- // Manipulation of the region stack
- bool region_stack_push(MemRegion mr) {
+ // (Lock-free) Manipulation of the region stack
+ bool region_stack_push_lock_free(MemRegion mr) {
// Currently we only call the lock-free version during evacuation
// pauses.
assert(SafepointSynchronize::is_at_safepoint(), "world should be stopped");
- _regionStack.push(mr);
+ _regionStack.push_lock_free(mr);
if (_regionStack.overflow()) {
set_has_overflown();
return false;
}
return true;
}
+
+ // Lock-free version of region-stack pop. Should only be
+ // called in tandem with other lock-free pops.
+ MemRegion region_stack_pop_lock_free() {
+ return _regionStack.pop_lock_free();
+ }
+
#if 0
- // Currently this is not used. See the comment in the .cpp file.
- MemRegion region_stack_pop() { return _regionStack.pop(); }
-#endif // 0
+ // The routines that manipulate the region stack with a lock are
+ // not currently used. They should be retained, however, as a
+ // diagnostic aid.
bool region_stack_push_with_lock(MemRegion mr) {
// Currently we only call the lock-based version during either
@@ -579,6 +589,7 @@
}
return true;
}
+
MemRegion region_stack_pop_with_lock() {
// Currently we only call the lock-based version during either
// concurrent marking or remark.
@@ -587,11 +598,21 @@
return _regionStack.pop_with_lock();
}
+#endif
int region_stack_size() { return _regionStack.size(); }
bool region_stack_overflow() { return _regionStack.overflow(); }
bool region_stack_empty() { return _regionStack.isEmpty(); }
+ // Iterate over any regions that were aborted while draining the
+ // region stack (any such regions are saved in the corresponding
+ // CMTask) and invalidate (i.e. assign to the empty MemRegion())
+ // any regions that point into the collection set.
+ bool invalidate_aborted_regions_in_cset();
+
+ // Returns true if there are any aborted memory regions.
+ bool has_aborted_regions();
+
bool concurrent_marking_in_progress() {
return _concurrent_marking_in_progress;
}
@@ -856,6 +877,15 @@
// stack.
HeapWord* _region_finger;
+ // If we abort while scanning a region we record the remaining
+ // unscanned portion and check this field when marking restarts.
+ // This avoids having to push on the region stack while other
+ // marking threads may still be popping regions.
+ // If we were to push the unscanned portion directly to the
+ // region stack then we would need to using locking versions
+ // of the push and pop operations.
+ MemRegion _aborted_region;
+
// the number of words this task has scanned
size_t _words_scanned;
// When _words_scanned reaches this limit, the regular clock is
@@ -1012,6 +1042,15 @@
void clear_has_aborted() { _has_aborted = false; }
bool claimed() { return _claimed; }
+ // Support routines for the partially scanned region that may be
+ // recorded as a result of aborting while draining the CMRegionStack
+ MemRegion aborted_region() { return _aborted_region; }
+ void set_aborted_region(MemRegion mr)
+ { _aborted_region = mr; }
+
+ // Clears any recorded partially scanned region
+ void clear_aborted_region() { set_aborted_region(MemRegion()); }
+
void set_oop_closure(OopClosure* oop_closure) {
_oop_closure = oop_closure;
}
--- a/hotspot/src/share/vm/gc_implementation/g1/concurrentMarkThread.cpp Fri Oct 15 09:38:20 2010 +0200
+++ b/hotspot/src/share/vm/gc_implementation/g1/concurrentMarkThread.cpp Fri Oct 15 02:59:48 2010 -0700
@@ -303,9 +303,10 @@
}
void ConcurrentMarkThread::sleepBeforeNextCycle() {
- clear_in_progress();
// We join here because we don't want to do the "shouldConcurrentMark()"
// below while the world is otherwise stopped.
+ assert(!in_progress(), "should have been cleared");
+
MutexLockerEx x(CGC_lock, Mutex::_no_safepoint_check_flag);
while (!started()) {
CGC_lock->wait(Mutex::_no_safepoint_check_flag);
--- a/hotspot/src/share/vm/gc_implementation/g1/concurrentMarkThread.hpp Fri Oct 15 09:38:20 2010 +0200
+++ b/hotspot/src/share/vm/gc_implementation/g1/concurrentMarkThread.hpp Fri Oct 15 02:59:48 2010 -0700
@@ -69,12 +69,12 @@
ConcurrentMark* cm() { return _cm; }
- void set_started() { _started = true; }
- void clear_started() { _started = false; }
+ void set_started() { assert(!_in_progress, "cycle in progress"); _started = true; }
+ void clear_started() { assert(_in_progress, "must be starting a cycle"); _started = false; }
bool started() { return _started; }
- void set_in_progress() { _in_progress = true; }
- void clear_in_progress() { _in_progress = false; }
+ void set_in_progress() { assert(_started, "must be starting a cycle"); _in_progress = true; }
+ void clear_in_progress() { assert(!_started, "must not be starting a new cycle"); _in_progress = false; }
bool in_progress() { return _in_progress; }
// This flag returns true from the moment a marking cycle is
--- a/hotspot/src/share/vm/gc_implementation/g1/dirtyCardQueue.hpp Fri Oct 15 09:38:20 2010 +0200
+++ b/hotspot/src/share/vm/gc_implementation/g1/dirtyCardQueue.hpp Fri Oct 15 02:59:48 2010 -0700
@@ -37,11 +37,10 @@
class DirtyCardQueue: public PtrQueue {
public:
DirtyCardQueue(PtrQueueSet* qset_, bool perm = false) :
- PtrQueue(qset_, perm)
- {
- // Dirty card queues are always active.
- _active = true;
- }
+ // Dirty card queues are always active, so we create them with their
+ // active field set to true.
+ PtrQueue(qset_, perm, true /* active */) { }
+
// Apply the closure to all elements, and reset the index to make the
// buffer empty. If a closure application returns "false", return
// "false" immediately, halting the iteration. If "consume" is true,
--- a/hotspot/src/share/vm/gc_implementation/g1/g1CollectedHeap.cpp Fri Oct 15 09:38:20 2010 +0200
+++ b/hotspot/src/share/vm/gc_implementation/g1/g1CollectedHeap.cpp Fri Oct 15 02:59:48 2010 -0700
@@ -961,7 +961,8 @@
}
// Rebuild remembered sets of all regions.
- if (ParallelGCThreads > 0) {
+
+ if (G1CollectedHeap::use_parallel_gc_threads()) {
ParRebuildRSTask rebuild_rs_task(this);
assert(check_heap_region_claim_values(
HeapRegion::InitialClaimValue), "sanity check");
@@ -1784,6 +1785,14 @@
_full_collections_completed += 1;
+ // We need to clear the "in_progress" flag in the CM thread before
+ // we wake up any waiters (especially when ExplicitInvokesConcurrent
+ // is set) so that if a waiter requests another System.gc() it doesn't
+ // incorrectly see that a marking cyle is still in progress.
+ if (outer) {
+ _cmThread->clear_in_progress();
+ }
+
// This notify_all() will ensure that a thread that called
// System.gc() with (with ExplicitGCInvokesConcurrent set or not)
// and it's waiting for a full GC to finish will be woken up. It is
@@ -1960,7 +1969,7 @@
int worker,
jint claim_value) {
const size_t regions = n_regions();
- const size_t worker_num = (ParallelGCThreads > 0 ? ParallelGCThreads : 1);
+ const size_t worker_num = (G1CollectedHeap::use_parallel_gc_threads() ? ParallelGCThreads : 1);
// try to spread out the starting points of the workers
const size_t start_index = regions / worker_num * (size_t) worker;
@@ -2527,7 +2536,7 @@
}
void G1CollectedHeap::print_gc_threads_on(outputStream* st) const {
- if (ParallelGCThreads > 0) {
+ if (G1CollectedHeap::use_parallel_gc_threads()) {
workers()->print_worker_threads_on(st);
}
@@ -2543,7 +2552,7 @@
}
void G1CollectedHeap::gc_threads_do(ThreadClosure* tc) const {
- if (ParallelGCThreads > 0) {
+ if (G1CollectedHeap::use_parallel_gc_threads()) {
workers()->threads_do(tc);
}
tc->do_thread(_cmThread);
@@ -3083,7 +3092,7 @@
if (r != NULL) {
r_used = r->used();
- if (ParallelGCThreads > 0) {
+ if (G1CollectedHeap::use_parallel_gc_threads()) {
// need to take the lock to guard against two threads calling
// get_gc_alloc_region concurrently (very unlikely but...)
MutexLockerEx x(ParGCRareEvent_lock, Mutex::_no_safepoint_check_flag);
@@ -4182,6 +4191,8 @@
// *** Common G1 Evacuation Stuff
+// This method is run in a GC worker.
+
void
G1CollectedHeap::
g1_process_strong_roots(bool collecting_perm_gen,
@@ -4259,7 +4270,7 @@
};
void G1CollectedHeap::save_marks() {
- if (ParallelGCThreads == 0) {
+ if (!CollectedHeap::use_parallel_gc_threads()) {
SaveMarksClosure sm;
heap_region_iterate(&sm);
}
@@ -4284,7 +4295,7 @@
assert(dirty_card_queue_set().completed_buffers_num() == 0, "Should be empty");
double start_par = os::elapsedTime();
- if (ParallelGCThreads > 0) {
+ if (G1CollectedHeap::use_parallel_gc_threads()) {
// The individual threads will set their evac-failure closures.
StrongRootsScope srs(this);
if (ParallelGCVerbose) G1ParScanThreadState::print_termination_stats_hdr();
--- a/hotspot/src/share/vm/gc_implementation/g1/g1CollectedHeap.hpp Fri Oct 15 09:38:20 2010 +0200
+++ b/hotspot/src/share/vm/gc_implementation/g1/g1CollectedHeap.hpp Fri Oct 15 02:59:48 2010 -0700
@@ -656,6 +656,9 @@
bool _unclean_regions_coming;
public:
+
+ SubTasksDone* process_strong_tasks() { return _process_strong_tasks; }
+
void set_refine_cte_cl_concurrency(bool concurrent);
RefToScanQueue *task_queue(int i) const;
@@ -684,7 +687,7 @@
void set_par_threads(int t) {
SharedHeap::set_par_threads(t);
- _process_strong_tasks->set_par_threads(t);
+ _process_strong_tasks->set_n_threads(t);
}
virtual CollectedHeap::Name kind() const {
@@ -1688,8 +1691,8 @@
ref = new_ref;
}
- int refs_to_scan() { return refs()->size(); }
- int overflowed_refs_to_scan() { return refs()->overflow_stack()->length(); }
+ int refs_to_scan() { return (int)refs()->size(); }
+ int overflowed_refs_to_scan() { return (int)refs()->overflow_stack()->size(); }
template <class T> void update_rs(HeapRegion* from, T* p, int tid) {
if (G1DeferredRSUpdate) {
--- a/hotspot/src/share/vm/gc_implementation/g1/g1CollectorPolicy.cpp Fri Oct 15 09:38:20 2010 +0200
+++ b/hotspot/src/share/vm/gc_implementation/g1/g1CollectorPolicy.cpp Fri Oct 15 02:59:48 2010 -0700
@@ -72,7 +72,10 @@
// </NEW PREDICTION>
G1CollectorPolicy::G1CollectorPolicy() :
- _parallel_gc_threads((ParallelGCThreads > 0) ? ParallelGCThreads : 1),
+ _parallel_gc_threads(G1CollectedHeap::use_parallel_gc_threads()
+ ? ParallelGCThreads : 1),
+
+
_n_pauses(0),
_recent_CH_strong_roots_times_ms(new TruncatedSeq(NumPrevPausesForHeuristics)),
_recent_G1_strong_roots_times_ms(new TruncatedSeq(NumPrevPausesForHeuristics)),
@@ -1073,7 +1076,7 @@
}
double G1CollectorPolicy::avg_value (double* data) {
- if (ParallelGCThreads > 0) {
+ if (G1CollectedHeap::use_parallel_gc_threads()) {
double ret = 0.0;
for (uint i = 0; i < ParallelGCThreads; ++i)
ret += data[i];
@@ -1084,7 +1087,7 @@
}
double G1CollectorPolicy::max_value (double* data) {
- if (ParallelGCThreads > 0) {
+ if (G1CollectedHeap::use_parallel_gc_threads()) {
double ret = data[0];
for (uint i = 1; i < ParallelGCThreads; ++i)
if (data[i] > ret)
@@ -1096,7 +1099,7 @@
}
double G1CollectorPolicy::sum_of_values (double* data) {
- if (ParallelGCThreads > 0) {
+ if (G1CollectedHeap::use_parallel_gc_threads()) {
double sum = 0.0;
for (uint i = 0; i < ParallelGCThreads; i++)
sum += data[i];
@@ -1110,7 +1113,7 @@
double* data2) {
double ret = data1[0] + data2[0];
- if (ParallelGCThreads > 0) {
+ if (G1CollectedHeap::use_parallel_gc_threads()) {
for (uint i = 1; i < ParallelGCThreads; ++i) {
double data = data1[i] + data2[i];
if (data > ret)
@@ -1126,7 +1129,7 @@
void G1CollectorPolicy::record_collection_pause_end() {
double end_time_sec = os::elapsedTime();
double elapsed_ms = _last_pause_time_ms;
- bool parallel = ParallelGCThreads > 0;
+ bool parallel = G1CollectedHeap::use_parallel_gc_threads();
double evac_ms = (end_time_sec - _cur_G1_strong_roots_end_sec) * 1000.0;
size_t rs_size =
_cur_collection_pause_used_regions_at_start - collection_set_size();
@@ -1941,7 +1944,7 @@
// Further, we're now always doing parallel collection. But I'm still
// leaving this here as a placeholder for a more precise assertion later.
// (DLD, 10/05.)
- assert((true || ParallelGCThreads > 0) ||
+ assert((true || G1CollectedHeap::use_parallel_gc_threads()) ||
_g1->evacuation_failed() ||
recent_survival_rate <= 1.0, "Or bad frac");
return recent_survival_rate;
@@ -1961,7 +1964,7 @@
// Further, we're now always doing parallel collection. But I'm still
// leaving this here as a placeholder for a more precise assertion later.
// (DLD, 10/05.)
- assert((true || ParallelGCThreads > 0) ||
+ assert((true || G1CollectedHeap::use_parallel_gc_threads()) ||
last_survival_rate <= 1.0, "Or bad frac");
return last_survival_rate;
} else {
@@ -2121,7 +2124,7 @@
}
void G1CollectorPolicy::print_summary(PauseSummary* summary) const {
- bool parallel = ParallelGCThreads > 0;
+ bool parallel = G1CollectedHeap::use_parallel_gc_threads();
MainBodySummary* body_summary = summary->main_body_summary();
if (summary->get_total_seq()->num() > 0) {
print_summary_sd(0, "Evacuation Pauses", summary->get_total_seq());
@@ -2559,7 +2562,7 @@
gclog_or_tty->print_cr(" clear marked regions + work1: %8.3f ms.",
(clear_marked_end - start)*1000.0);
}
- if (ParallelGCThreads > 0) {
+ if (G1CollectedHeap::use_parallel_gc_threads()) {
const size_t OverpartitionFactor = 4;
const size_t MinWorkUnit = 8;
const size_t WorkUnit =
--- a/hotspot/src/share/vm/gc_implementation/g1/g1MarkSweep.cpp Fri Oct 15 09:38:20 2010 +0200
+++ b/hotspot/src/share/vm/gc_implementation/g1/g1MarkSweep.cpp Fri Oct 15 02:59:48 2010 -0700
@@ -101,22 +101,6 @@
GenMarkSweep::_preserved_count_max = 0;
GenMarkSweep::_preserved_marks = NULL;
GenMarkSweep::_preserved_count = 0;
- GenMarkSweep::_preserved_mark_stack = NULL;
- GenMarkSweep::_preserved_oop_stack = NULL;
-
- GenMarkSweep::_marking_stack =
- new (ResourceObj::C_HEAP) GrowableArray<oop>(4000, true);
- GenMarkSweep::_objarray_stack =
- new (ResourceObj::C_HEAP) GrowableArray<ObjArrayTask>(50, true);
-
- int size = SystemDictionary::number_of_classes() * 2;
- GenMarkSweep::_revisit_klass_stack =
- new (ResourceObj::C_HEAP) GrowableArray<Klass*>(size, true);
- // (#klass/k)^2 for k ~ 10 appears a better fit, but this will have to do
- // for now until we have a chance to work out a more optimal setting.
- GenMarkSweep::_revisit_mdo_stack =
- new (ResourceObj::C_HEAP) GrowableArray<DataLayout*>(size*2, true);
-
}
void G1MarkSweep::mark_sweep_phase1(bool& marked_for_unloading,
@@ -145,7 +129,7 @@
// Follow system dictionary roots and unload classes
bool purged_class = SystemDictionary::do_unloading(&GenMarkSweep::is_alive);
- assert(GenMarkSweep::_marking_stack->is_empty(),
+ assert(GenMarkSweep::_marking_stack.is_empty(),
"stack should be empty by now");
// Follow code cache roots (has to be done after system dictionary,
@@ -157,19 +141,19 @@
// Update subklass/sibling/implementor links of live klasses
GenMarkSweep::follow_weak_klass_links();
- assert(GenMarkSweep::_marking_stack->is_empty(),
+ assert(GenMarkSweep::_marking_stack.is_empty(),
"stack should be empty by now");
// Visit memoized MDO's and clear any unmarked weak refs
GenMarkSweep::follow_mdo_weak_refs();
- assert(GenMarkSweep::_marking_stack->is_empty(), "just drained");
+ assert(GenMarkSweep::_marking_stack.is_empty(), "just drained");
// Visit symbol and interned string tables and delete unmarked oops
SymbolTable::unlink(&GenMarkSweep::is_alive);
StringTable::unlink(&GenMarkSweep::is_alive);
- assert(GenMarkSweep::_marking_stack->is_empty(),
+ assert(GenMarkSweep::_marking_stack.is_empty(),
"stack should be empty by now");
}
--- a/hotspot/src/share/vm/gc_implementation/g1/g1RemSet.cpp Fri Oct 15 09:38:20 2010 +0200
+++ b/hotspot/src/share/vm/gc_implementation/g1/g1RemSet.cpp Fri Oct 15 02:59:48 2010 -0700
@@ -523,7 +523,7 @@
assert(!_traversal_in_progress, "Invariant between iterations.");
set_traversal(true);
if (ParallelGCThreads > 0) {
- _seq_task->set_par_threads((int)n_workers());
+ _seq_task->set_n_threads((int)n_workers());
}
guarantee( _cards_scanned == NULL, "invariant" );
_cards_scanned = NEW_C_HEAP_ARRAY(size_t, n_workers());
--- a/hotspot/src/share/vm/gc_implementation/g1/ptrQueue.hpp Fri Oct 15 09:38:20 2010 +0200
+++ b/hotspot/src/share/vm/gc_implementation/g1/ptrQueue.hpp Fri Oct 15 02:59:48 2010 -0700
@@ -89,6 +89,10 @@
return _buf == NULL ? 0 : _sz - _index;
}
+ bool is_empty() {
+ return _buf == NULL || _sz == _index;
+ }
+
// Set the "active" property of the queue to "b". An enqueue to an
// inactive thread is a no-op. Setting a queue to inactive resets its
// log to the empty state.
--- a/hotspot/src/share/vm/gc_implementation/g1/satbQueue.hpp Fri Oct 15 09:38:20 2010 +0200
+++ b/hotspot/src/share/vm/gc_implementation/g1/satbQueue.hpp Fri Oct 15 02:59:48 2010 -0700
@@ -29,7 +29,12 @@
class ObjPtrQueue: public PtrQueue {
public:
ObjPtrQueue(PtrQueueSet* qset_, bool perm = false) :
- PtrQueue(qset_, perm, qset_->is_active()) { }
+ // SATB queues are only active during marking cycles. We create
+ // them with their active field set to false. If a thread is
+ // created during a cycle and its SATB queue needs to be activated
+ // before the thread starts running, we'll need to set its active
+ // field to true. This is done in JavaThread::initialize_queues().
+ PtrQueue(qset_, perm, false /* active */) { }
// Apply the closure to all elements, and reset the index to make the
// buffer empty.
void apply_closure(ObjectClosure* cl);
--- a/hotspot/src/share/vm/gc_implementation/includeDB_gc_concurrentMarkSweep Fri Oct 15 09:38:20 2010 +0200
+++ b/hotspot/src/share/vm/gc_implementation/includeDB_gc_concurrentMarkSweep Fri Oct 15 02:59:48 2010 -0700
@@ -171,6 +171,7 @@
concurrentMarkSweepGeneration.hpp generationCounters.hpp
concurrentMarkSweepGeneration.hpp memoryService.hpp
concurrentMarkSweepGeneration.hpp mutexLocker.hpp
+concurrentMarkSweepGeneration.hpp stack.inline.hpp
concurrentMarkSweepGeneration.hpp taskqueue.hpp
concurrentMarkSweepGeneration.hpp virtualspace.hpp
concurrentMarkSweepGeneration.hpp yieldingWorkgroup.hpp
--- a/hotspot/src/share/vm/gc_implementation/includeDB_gc_parallelScavenge Fri Oct 15 09:38:20 2010 +0200
+++ b/hotspot/src/share/vm/gc_implementation/includeDB_gc_parallelScavenge Fri Oct 15 02:59:48 2010 -0700
@@ -187,9 +187,11 @@
psCompactionManager.cpp psParallelCompact.hpp
psCompactionManager.cpp psCompactionManager.hpp
psCompactionManager.cpp psOldGen.hpp
+psCompactionManager.cpp stack.inline.hpp
psCompactionManager.cpp systemDictionary.hpp
psCompactionManager.hpp allocation.hpp
+psCompactionManager.hpp stack.hpp
psCompactionManager.hpp taskqueue.hpp
psCompactionManager.inline.hpp psCompactionManager.hpp
@@ -233,12 +235,14 @@
psMarkSweep.cpp referenceProcessor.hpp
psMarkSweep.cpp safepoint.hpp
psMarkSweep.cpp spaceDecorator.hpp
+psMarkSweep.cpp stack.inline.hpp
psMarkSweep.cpp symbolTable.hpp
psMarkSweep.cpp systemDictionary.hpp
psMarkSweep.cpp vmThread.hpp
psMarkSweep.hpp markSweep.inline.hpp
psMarkSweep.hpp collectorCounters.hpp
+psMarkSweep.hpp stack.hpp
psMarkSweepDecorator.cpp liveRange.hpp
psMarkSweepDecorator.cpp markSweep.inline.hpp
@@ -280,6 +284,7 @@
psParallelCompact.cpp referencePolicy.hpp
psParallelCompact.cpp referenceProcessor.hpp
psParallelCompact.cpp safepoint.hpp
+psParallelCompact.cpp stack.inline.hpp
psParallelCompact.cpp symbolTable.hpp
psParallelCompact.cpp systemDictionary.hpp
psParallelCompact.cpp vmThread.hpp
@@ -367,6 +372,7 @@
psScavenge.cpp referenceProcessor.hpp
psScavenge.cpp resourceArea.hpp
psScavenge.cpp spaceDecorator.hpp
+psScavenge.cpp stack.inline.hpp
psScavenge.cpp threadCritical.hpp
psScavenge.cpp vmThread.hpp
psScavenge.cpp vm_operations.hpp
@@ -376,6 +382,7 @@
psScavenge.hpp collectorCounters.hpp
psScavenge.hpp oop.hpp
psScavenge.hpp psVirtualspace.hpp
+psScavenge.hpp stack.hpp
psScavenge.inline.hpp cardTableExtension.hpp
psScavenge.inline.hpp parallelScavengeHeap.hpp
--- a/hotspot/src/share/vm/gc_implementation/includeDB_gc_serial Fri Oct 15 09:38:20 2010 +0200
+++ b/hotspot/src/share/vm/gc_implementation/includeDB_gc_serial Fri Oct 15 02:59:48 2010 -0700
@@ -93,11 +93,13 @@
markSweep.hpp growableArray.hpp
markSweep.hpp markOop.hpp
markSweep.hpp oop.hpp
+markSweep.hpp stack.hpp
markSweep.hpp timer.hpp
markSweep.hpp universe.hpp
markSweep.inline.hpp collectedHeap.hpp
markSweep.inline.hpp markSweep.hpp
+markSweep.inline.hpp stack.inline.hpp
mutableSpace.hpp immutableSpace.hpp
mutableSpace.hpp memRegion.hpp
--- a/hotspot/src/share/vm/gc_implementation/parNew/parCardTableModRefBS.cpp Fri Oct 15 09:38:20 2010 +0200
+++ b/hotspot/src/share/vm/gc_implementation/parNew/parCardTableModRefBS.cpp Fri Oct 15 02:59:48 2010 -0700
@@ -1,5 +1,5 @@
/*
- * Copyright (c) 2007, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2007, 2010 Oracle and/or its affiliates. All rights reserved.
* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
*
* This code is free software; you can redistribute it and/or modify it
@@ -44,7 +44,7 @@
int n_strides = n_threads * StridesPerThread;
SequentialSubTasksDone* pst = sp->par_seq_tasks();
- pst->set_par_threads(n_threads);
+ pst->set_n_threads(n_threads);
pst->set_n_tasks(n_strides);
int stride = 0;
--- a/hotspot/src/share/vm/gc_implementation/parNew/parNewGeneration.cpp Fri Oct 15 09:38:20 2010 +0200
+++ b/hotspot/src/share/vm/gc_implementation/parNew/parNewGeneration.cpp Fri Oct 15 02:59:48 2010 -0700
@@ -34,12 +34,12 @@
Generation* old_gen_,
int thread_num_,
ObjToScanQueueSet* work_queue_set_,
- GrowableArray<oop>** overflow_stack_set_,
+ Stack<oop>* overflow_stacks_,
size_t desired_plab_sz_,
ParallelTaskTerminator& term_) :
_to_space(to_space_), _old_gen(old_gen_), _young_gen(gen_), _thread_num(thread_num_),
_work_queue(work_queue_set_->queue(thread_num_)), _to_space_full(false),
- _overflow_stack(overflow_stack_set_[thread_num_]),
+ _overflow_stack(overflow_stacks_ ? overflow_stacks_ + thread_num_ : NULL),
_ageTable(false), // false ==> not the global age table, no perf data.
_to_space_alloc_buffer(desired_plab_sz_),
_to_space_closure(gen_, this), _old_gen_closure(gen_, this),
@@ -159,11 +159,12 @@
assert(ParGCUseLocalOverflow, "Else should not call");
assert(young_gen()->overflow_list() == NULL, "Error");
ObjToScanQueue* queue = work_queue();
- GrowableArray<oop>* of_stack = overflow_stack();
- uint num_overflow_elems = of_stack->length();
- uint num_take_elems = MIN2(MIN2((queue->max_elems() - queue->size())/4,
- (juint)ParGCDesiredObjsFromOverflowList),
- num_overflow_elems);
+ Stack<oop>* const of_stack = overflow_stack();
+ const size_t num_overflow_elems = of_stack->size();
+ const size_t space_available = queue->max_elems() - queue->size();
+ const size_t num_take_elems = MIN3(space_available / 4,
+ ParGCDesiredObjsFromOverflowList,
+ num_overflow_elems);
// Transfer the most recent num_take_elems from the overflow
// stack to our work queue.
for (size_t i = 0; i != num_take_elems; i++) {
@@ -271,7 +272,7 @@
ParNewGeneration& gen,
Generation& old_gen,
ObjToScanQueueSet& queue_set,
- GrowableArray<oop>** overflow_stacks_,
+ Stack<oop>* overflow_stacks_,
size_t desired_plab_sz,
ParallelTaskTerminator& term);
@@ -302,17 +303,19 @@
ParScanThreadStateSet::ParScanThreadStateSet(
int num_threads, Space& to_space, ParNewGeneration& gen,
Generation& old_gen, ObjToScanQueueSet& queue_set,
- GrowableArray<oop>** overflow_stack_set_,
+ Stack<oop>* overflow_stacks,
size_t desired_plab_sz, ParallelTaskTerminator& term)
: ResourceArray(sizeof(ParScanThreadState), num_threads),
_gen(gen), _next_gen(old_gen), _term(term)
{
assert(num_threads > 0, "sanity check!");
+ assert(ParGCUseLocalOverflow == (overflow_stacks != NULL),
+ "overflow_stack allocation mismatch");
// Initialize states.
for (int i = 0; i < num_threads; ++i) {
new ((ParScanThreadState*)_data + i)
ParScanThreadState(&to_space, &gen, &old_gen, i, &queue_set,
- overflow_stack_set_, desired_plab_sz, term);
+ overflow_stacks, desired_plab_sz, term);
}
}
@@ -596,14 +599,11 @@
for (uint i2 = 0; i2 < ParallelGCThreads; i2++)
_task_queues->queue(i2)->initialize();
- _overflow_stacks = NEW_C_HEAP_ARRAY(GrowableArray<oop>*, ParallelGCThreads);
- guarantee(_overflow_stacks != NULL, "Overflow stack set allocation failure");
- for (uint i = 0; i < ParallelGCThreads; i++) {
- if (ParGCUseLocalOverflow) {
- _overflow_stacks[i] = new (ResourceObj::C_HEAP) GrowableArray<oop>(512, true);
- guarantee(_overflow_stacks[i] != NULL, "Overflow Stack allocation failure.");
- } else {
- _overflow_stacks[i] = NULL;
+ _overflow_stacks = NULL;
+ if (ParGCUseLocalOverflow) {
+ _overflow_stacks = NEW_C_HEAP_ARRAY(Stack<oop>, ParallelGCThreads);
+ for (size_t i = 0; i < ParallelGCThreads; ++i) {
+ new (_overflow_stacks + i) Stack<oop>();
}
}
@@ -937,12 +937,9 @@
} else {
assert(HandlePromotionFailure,
"Should only be here if promotion failure handling is on");
- if (_promo_failure_scan_stack != NULL) {
- // Can be non-null because of reference processing.
- // Free stack with its elements.
- delete _promo_failure_scan_stack;
- _promo_failure_scan_stack = NULL;
- }
+ assert(_promo_failure_scan_stack.is_empty(), "post condition");
+ _promo_failure_scan_stack.clear(true); // Clear cached segments.
+
remove_forwarding_pointers();
if (PrintGCDetails) {
gclog_or_tty->print(" (promotion failed)");
@@ -1397,8 +1394,8 @@
size_t objsFromOverflow = MIN2((size_t)(work_q->max_elems() - work_q->size())/4,
(size_t)ParGCDesiredObjsFromOverflowList);
+ assert(!UseCompressedOops, "Error");
assert(par_scan_state->overflow_stack() == NULL, "Error");
- assert(!UseCompressedOops, "Error");
if (_overflow_list == NULL) return false;
// Otherwise, there was something there; try claiming the list.
@@ -1533,3 +1530,7 @@
const char* ParNewGeneration::name() const {
return "par new generation";
}
+
+bool ParNewGeneration::in_use() {
+ return UseParNewGC && ParallelGCThreads > 0;
+}
--- a/hotspot/src/share/vm/gc_implementation/parNew/parNewGeneration.hpp Fri Oct 15 09:38:20 2010 +0200
+++ b/hotspot/src/share/vm/gc_implementation/parNew/parNewGeneration.hpp Fri Oct 15 02:59:48 2010 -0700
@@ -52,7 +52,7 @@
friend class ParScanThreadStateSet;
private:
ObjToScanQueue *_work_queue;
- GrowableArray<oop>* _overflow_stack;
+ Stack<oop>* const _overflow_stack;
ParGCAllocBuffer _to_space_alloc_buffer;
@@ -120,7 +120,7 @@
ParScanThreadState(Space* to_space_, ParNewGeneration* gen_,
Generation* old_gen_, int thread_num_,
ObjToScanQueueSet* work_queue_set_,
- GrowableArray<oop>** overflow_stack_set_,
+ Stack<oop>* overflow_stacks_,
size_t desired_plab_sz_,
ParallelTaskTerminator& term_);
@@ -144,7 +144,7 @@
void trim_queues(int max_size);
// Private overflow stack usage
- GrowableArray<oop>* overflow_stack() { return _overflow_stack; }
+ Stack<oop>* overflow_stack() { return _overflow_stack; }
bool take_from_overflow_stack();
void push_on_overflow_stack(oop p);
@@ -301,7 +301,7 @@
ObjToScanQueueSet* _task_queues;
// Per-worker-thread local overflow stacks
- GrowableArray<oop>** _overflow_stacks;
+ Stack<oop>* _overflow_stacks;
// Desired size of survivor space plab's
PLABStats _plab_stats;
@@ -350,6 +350,8 @@
delete _task_queues;
}
+ static bool in_use();
+
virtual void ref_processor_init();
virtual Generation::Name kind() { return Generation::ParNew; }
virtual const char* name() const;
--- a/hotspot/src/share/vm/gc_implementation/parallelScavenge/pcTasks.cpp Fri Oct 15 09:38:20 2010 +0200
+++ b/hotspot/src/share/vm/gc_implementation/parallelScavenge/pcTasks.cpp Fri Oct 15 02:59:48 2010 -0700
@@ -59,8 +59,6 @@
PrintGCDetails && TraceParallelOldGCTasks, true, gclog_or_tty));
ParCompactionManager* cm =
ParCompactionManager::gc_thread_compaction_manager(which);
- assert(cm->stacks_have_been_allocated(),
- "Stack space has not been allocated");
PSParallelCompact::MarkAndPushClosure mark_and_push_closure(cm);
switch (_root_type) {
@@ -119,7 +117,6 @@
// Do the real work
cm->follow_marking_stacks();
- // cm->deallocate_stacks();
}
@@ -135,8 +132,6 @@
PrintGCDetails && TraceParallelOldGCTasks, true, gclog_or_tty));
ParCompactionManager* cm =
ParCompactionManager::gc_thread_compaction_manager(which);
- assert(cm->stacks_have_been_allocated(),
- "Stack space has not been allocated");
PSParallelCompact::MarkAndPushClosure mark_and_push_closure(cm);
PSParallelCompact::FollowStackClosure follow_stack_closure(cm);
_rp_task.work(_work_id, *PSParallelCompact::is_alive_closure(),
--- a/hotspot/src/share/vm/gc_implementation/parallelScavenge/pcTasks.hpp Fri Oct 15 09:38:20 2010 +0200
+++ b/hotspot/src/share/vm/gc_implementation/parallelScavenge/pcTasks.hpp Fri Oct 15 02:59:48 2010 -0700
@@ -1,5 +1,5 @@
/*
- * Copyright (c) 2005, 2008, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2005, 2010, Oracle and/or its affiliates. All rights reserved.
* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
*
* This code is free software; you can redistribute it and/or modify it
@@ -242,7 +242,11 @@
//
class DrainStacksCompactionTask : public GCTask {
+ uint _stack_index;
+ uint stack_index() { return _stack_index; }
public:
+ DrainStacksCompactionTask(uint stack_index) : GCTask(),
+ _stack_index(stack_index) {};
char* name() { return (char *)"drain-region-task"; }
virtual void do_it(GCTaskManager* manager, uint which);
};
--- a/hotspot/src/share/vm/gc_implementation/parallelScavenge/psCompactionManager.cpp Fri Oct 15 09:38:20 2010 +0200
+++ b/hotspot/src/share/vm/gc_implementation/parallelScavenge/psCompactionManager.cpp Fri Oct 15 02:59:48 2010 -0700
@@ -46,23 +46,6 @@
marking_stack()->initialize();
_objarray_stack.initialize();
region_stack()->initialize();
-
- // Note that _revisit_klass_stack is allocated out of the
- // C heap (as opposed to out of ResourceArena).
- int size =
- (SystemDictionary::number_of_classes() * 2) * 2 / ParallelGCThreads;
- _revisit_klass_stack = new (ResourceObj::C_HEAP) GrowableArray<Klass*>(size, true);
- // From some experiments (#klass/k)^2 for k = 10 seems a better fit, but this will
- // have to do for now until we are able to investigate a more optimal setting.
- _revisit_mdo_stack = new (ResourceObj::C_HEAP) GrowableArray<DataLayout*>(size*2, true);
-}
-
-ParCompactionManager::~ParCompactionManager() {
- delete _revisit_klass_stack;
- delete _revisit_mdo_stack;
- // _manager_array and _stack_array are statics
- // shared with all instances of ParCompactionManager
- // should not be deallocated.
}
void ParCompactionManager::initialize(ParMarkBitMap* mbm) {
@@ -134,9 +117,9 @@
}
void ParCompactionManager::reset() {
- for(uint i=0; i<ParallelGCThreads+1; i++) {
- manager_array(i)->revisit_klass_stack()->clear();
- manager_array(i)->revisit_mdo_stack()->clear();
+ for(uint i = 0; i < ParallelGCThreads + 1; i++) {
+ assert(manager_array(i)->revisit_klass_stack()->is_empty(), "sanity");
+ assert(manager_array(i)->revisit_mdo_stack()->is_empty(), "sanity");
}
}
@@ -178,10 +161,3 @@
}
} while (!region_stack()->is_empty());
}
-
-#ifdef ASSERT
-bool ParCompactionManager::stacks_have_been_allocated() {
- return (revisit_klass_stack()->data_addr() != NULL &&
- revisit_mdo_stack()->data_addr() != NULL);
-}
-#endif
--- a/hotspot/src/share/vm/gc_implementation/parallelScavenge/psCompactionManager.hpp Fri Oct 15 09:38:20 2010 +0200
+++ b/hotspot/src/share/vm/gc_implementation/parallelScavenge/psCompactionManager.hpp Fri Oct 15 02:59:48 2010 -0700
@@ -80,10 +80,9 @@
// type of TaskQueue.
RegionTaskQueue _region_stack;
-#if 1 // does this happen enough to need a per thread stack?
- GrowableArray<Klass*>* _revisit_klass_stack;
- GrowableArray<DataLayout*>* _revisit_mdo_stack;
-#endif
+ Stack<Klass*> _revisit_klass_stack;
+ Stack<DataLayout*> _revisit_mdo_stack;
+
static ParMarkBitMap* _mark_bitmap;
Action _action;
@@ -113,10 +112,7 @@
inline static ParCompactionManager* manager_array(int index);
ParCompactionManager();
- ~ParCompactionManager();
- void allocate_stacks();
- void deallocate_stacks();
ParMarkBitMap* mark_bitmap() { return _mark_bitmap; }
// Take actions in preparation for a compaction.
@@ -129,11 +125,8 @@
bool should_verify_only();
bool should_reset_only();
-#if 1
- // Probably stays as a growable array
- GrowableArray<Klass*>* revisit_klass_stack() { return _revisit_klass_stack; }
- GrowableArray<DataLayout*>* revisit_mdo_stack() { return _revisit_mdo_stack; }
-#endif
+ Stack<Klass*>* revisit_klass_stack() { return &_revisit_klass_stack; }
+ Stack<DataLayout*>* revisit_mdo_stack() { return &_revisit_mdo_stack; }
// Save for later processing. Must not fail.
inline void push(oop obj) { _marking_stack.push(obj); }
@@ -162,10 +155,6 @@
// Process tasks remaining on any stack
void drain_region_stacks();
- // Debugging support
-#ifdef ASSERT
- bool stacks_have_been_allocated();
-#endif
};
inline ParCompactionManager* ParCompactionManager::manager_array(int index) {
--- a/hotspot/src/share/vm/gc_implementation/parallelScavenge/psMarkSweep.cpp Fri Oct 15 09:38:20 2010 +0200
+++ b/hotspot/src/share/vm/gc_implementation/parallelScavenge/psMarkSweep.cpp Fri Oct 15 02:59:48 2010 -0700
@@ -466,33 +466,16 @@
_preserved_count_max = pointer_delta(to_space->end(), to_space->top(), sizeof(jbyte));
// Now divide by the size of a PreservedMark
_preserved_count_max /= sizeof(PreservedMark);
-
- _preserved_mark_stack = NULL;
- _preserved_oop_stack = NULL;
-
- _marking_stack = new (ResourceObj::C_HEAP) GrowableArray<oop>(4000, true);
- _objarray_stack = new (ResourceObj::C_HEAP) GrowableArray<ObjArrayTask>(50, true);
-
- int size = SystemDictionary::number_of_classes() * 2;
- _revisit_klass_stack = new (ResourceObj::C_HEAP) GrowableArray<Klass*>(size, true);
- // (#klass/k)^2, for k ~ 10 appears a better setting, but this will have to do for
- // now until we investigate a more optimal setting.
- _revisit_mdo_stack = new (ResourceObj::C_HEAP) GrowableArray<DataLayout*>(size*2, true);
}
void PSMarkSweep::deallocate_stacks() {
- if (_preserved_oop_stack) {
- delete _preserved_mark_stack;
- _preserved_mark_stack = NULL;
- delete _preserved_oop_stack;
- _preserved_oop_stack = NULL;
- }
-
- delete _marking_stack;
- delete _objarray_stack;
- delete _revisit_klass_stack;
- delete _revisit_mdo_stack;
+ _preserved_mark_stack.clear(true);
+ _preserved_oop_stack.clear(true);
+ _marking_stack.clear();
+ _objarray_stack.clear(true);
+ _revisit_klass_stack.clear(true);
+ _revisit_mdo_stack.clear(true);
}
void PSMarkSweep::mark_sweep_phase1(bool clear_all_softrefs) {
@@ -542,17 +525,17 @@
// Update subklass/sibling/implementor links of live klasses
follow_weak_klass_links();
- assert(_marking_stack->is_empty(), "just drained");
+ assert(_marking_stack.is_empty(), "just drained");
// Visit memoized mdo's and clear unmarked weak refs
follow_mdo_weak_refs();
- assert(_marking_stack->is_empty(), "just drained");
+ assert(_marking_stack.is_empty(), "just drained");
// Visit symbol and interned string tables and delete unmarked oops
SymbolTable::unlink(is_alive_closure());
StringTable::unlink(is_alive_closure());
- assert(_marking_stack->is_empty(), "stack should be empty by now");
+ assert(_marking_stack.is_empty(), "stack should be empty by now");
}
--- a/hotspot/src/share/vm/gc_implementation/parallelScavenge/psParallelCompact.cpp Fri Oct 15 09:38:20 2010 +0200
+++ b/hotspot/src/share/vm/gc_implementation/parallelScavenge/psParallelCompact.cpp Fri Oct 15 02:59:48 2010 -0700
@@ -2170,6 +2170,16 @@
heap->update_counters();
}
+#ifdef ASSERT
+ for (size_t i = 0; i < ParallelGCThreads + 1; ++i) {
+ ParCompactionManager* const cm =
+ ParCompactionManager::manager_array(int(i));
+ assert(cm->marking_stack()->is_empty(), "should be empty");
+ assert(cm->region_stack()->is_empty(), "should be empty");
+ assert(cm->revisit_klass_stack()->is_empty(), "should be empty");
+ }
+#endif // ASSERT
+
if (VerifyAfterGC && heap->total_collections() >= VerifyGCStartAt) {
HandleMark hm; // Discard invalid handles created during verification
gclog_or_tty->print(" VerifyAfterGC:");
@@ -2449,7 +2459,7 @@
const unsigned int task_count = MAX2(parallel_gc_threads, 1U);
for (unsigned int j = 0; j < task_count; j++) {
- q->enqueue(new DrainStacksCompactionTask());
+ q->enqueue(new DrainStacksCompactionTask(j));
}
// Find all regions that are available (can be filled immediately) and
@@ -2711,21 +2721,22 @@
// All klasses on the revisit stack are marked at this point.
// Update and follow all subklass, sibling and implementor links.
if (PrintRevisitStats) {
- gclog_or_tty->print_cr("#classes in system dictionary = %d", SystemDictionary::number_of_classes());
+ gclog_or_tty->print_cr("#classes in system dictionary = %d",
+ SystemDictionary::number_of_classes());
}
for (uint i = 0; i < ParallelGCThreads + 1; i++) {
ParCompactionManager* cm = ParCompactionManager::manager_array(i);
KeepAliveClosure keep_alive_closure(cm);
- int length = cm->revisit_klass_stack()->length();
+ Stack<Klass*>* const rks = cm->revisit_klass_stack();
if (PrintRevisitStats) {
- gclog_or_tty->print_cr("Revisit klass stack[%d] length = %d", i, length);
+ gclog_or_tty->print_cr("Revisit klass stack[%u] length = " SIZE_FORMAT,
+ i, rks->size());
}
- for (int j = 0; j < length; j++) {
- cm->revisit_klass_stack()->at(j)->follow_weak_klass_links(
- is_alive_closure(),
- &keep_alive_closure);
+ while (!rks->is_empty()) {
+ Klass* const k = rks->pop();
+ k->follow_weak_klass_links(is_alive_closure(), &keep_alive_closure);
}
- // revisit_klass_stack is cleared in reset()
+
cm->follow_marking_stacks();
}
}
@@ -2744,19 +2755,20 @@
// we can visit and clear any weak references from MDO's which
// we memoized during the strong marking phase.
if (PrintRevisitStats) {
- gclog_or_tty->print_cr("#classes in system dictionary = %d", SystemDictionary::number_of_classes());
+ gclog_or_tty->print_cr("#classes in system dictionary = %d",
+ SystemDictionary::number_of_classes());
}
for (uint i = 0; i < ParallelGCThreads + 1; i++) {
ParCompactionManager* cm = ParCompactionManager::manager_array(i);
- GrowableArray<DataLayout*>* rms = cm->revisit_mdo_stack();
- int length = rms->length();
+ Stack<DataLayout*>* rms = cm->revisit_mdo_stack();
if (PrintRevisitStats) {
- gclog_or_tty->print_cr("Revisit MDO stack[%d] length = %d", i, length);
+ gclog_or_tty->print_cr("Revisit MDO stack[%u] size = " SIZE_FORMAT,
+ i, rms->size());
}
- for (int j = 0; j < length; j++) {
- rms->at(j)->follow_weak_refs(is_alive_closure());
+ while (!rms->is_empty()) {
+ rms->pop()->follow_weak_refs(is_alive_closure());
}
- // revisit_mdo_stack is cleared in reset()
+
cm->follow_marking_stacks();
}
}
--- a/hotspot/src/share/vm/gc_implementation/parallelScavenge/psPromotionManager.cpp Fri Oct 15 09:38:20 2010 +0200
+++ b/hotspot/src/share/vm/gc_implementation/parallelScavenge/psPromotionManager.cpp Fri Oct 15 02:59:48 2010 -0700
@@ -185,7 +185,6 @@
void PSPromotionManager::drain_stacks_depth(bool totally_drain) {
- assert(claimed_stack_depth()->overflow_stack() != NULL, "invariant");
totally_drain = totally_drain || _totally_drain;
#ifdef ASSERT
--- a/hotspot/src/share/vm/gc_implementation/parallelScavenge/psScavenge.cpp Fri Oct 15 09:38:20 2010 +0200
+++ b/hotspot/src/share/vm/gc_implementation/parallelScavenge/psScavenge.cpp Fri Oct 15 02:59:48 2010 -0700
@@ -34,9 +34,10 @@
int PSScavenge::_tenuring_threshold = 0;
HeapWord* PSScavenge::_young_generation_boundary = NULL;
elapsedTimer PSScavenge::_accumulated_time;
-GrowableArray<markOop>* PSScavenge::_preserved_mark_stack = NULL;
-GrowableArray<oop>* PSScavenge::_preserved_oop_stack = NULL;
+Stack<markOop> PSScavenge::_preserved_mark_stack;
+Stack<oop> PSScavenge::_preserved_oop_stack;
CollectorCounters* PSScavenge::_counters = NULL;
+bool PSScavenge::_promotion_failed = false;
// Define before use
class PSIsAliveClosure: public BoolObjectClosure {
@@ -223,6 +224,9 @@
assert(SafepointSynchronize::is_at_safepoint(), "should be at safepoint");
assert(Thread::current() == (Thread*)VMThread::vm_thread(), "should be in vm thread");
+ assert(_preserved_mark_stack.is_empty(), "should be empty");
+ assert(_preserved_oop_stack.is_empty(), "should be empty");
+
TimeStamp scavenge_entry;
TimeStamp scavenge_midpoint;
TimeStamp scavenge_exit;
@@ -636,24 +640,20 @@
young_gen->object_iterate(&unforward_closure);
if (PrintGC && Verbose) {
- gclog_or_tty->print_cr("Restoring %d marks",
- _preserved_oop_stack->length());
+ gclog_or_tty->print_cr("Restoring %d marks", _preserved_oop_stack.size());
}
// Restore any saved marks.
- for (int i=0; i < _preserved_oop_stack->length(); i++) {
- oop obj = _preserved_oop_stack->at(i);
- markOop mark = _preserved_mark_stack->at(i);
+ while (!_preserved_oop_stack.is_empty()) {
+ oop obj = _preserved_oop_stack.pop();
+ markOop mark = _preserved_mark_stack.pop();
obj->set_mark(mark);
}
- // Deallocate the preserved mark and oop stacks.
- // The stacks were allocated as CHeap objects, so
- // we must call delete to prevent mem leaks.
- delete _preserved_mark_stack;
- _preserved_mark_stack = NULL;
- delete _preserved_oop_stack;
- _preserved_oop_stack = NULL;
+ // Clear the preserved mark and oop stack caches.
+ _preserved_mark_stack.clear(true);
+ _preserved_oop_stack.clear(true);
+ _promotion_failed = false;
}
// Reset the PromotionFailureALot counters.
@@ -661,27 +661,16 @@
}
// This method is called whenever an attempt to promote an object
-// fails. Some markOops will need preserving, some will not. Note
+// fails. Some markOops will need preservation, some will not. Note
// that the entire eden is traversed after a failed promotion, with
// all forwarded headers replaced by the default markOop. This means
// it is not neccessary to preserve most markOops.
void PSScavenge::oop_promotion_failed(oop obj, markOop obj_mark) {
- if (_preserved_mark_stack == NULL) {
- ThreadCritical tc; // Lock and retest
- if (_preserved_mark_stack == NULL) {
- assert(_preserved_oop_stack == NULL, "Sanity");
- _preserved_mark_stack = new (ResourceObj::C_HEAP) GrowableArray<markOop>(40, true);
- _preserved_oop_stack = new (ResourceObj::C_HEAP) GrowableArray<oop>(40, true);
- }
- }
-
- // Because we must hold the ThreadCritical lock before using
- // the stacks, we should be safe from observing partial allocations,
- // which are also guarded by the ThreadCritical lock.
+ _promotion_failed = true;
if (obj_mark->must_be_preserved_for_promotion_failure(obj)) {
ThreadCritical tc;
- _preserved_oop_stack->push(obj);
- _preserved_mark_stack->push(obj_mark);
+ _preserved_oop_stack.push(obj);
+ _preserved_mark_stack.push(obj_mark);
}
}
--- a/hotspot/src/share/vm/gc_implementation/parallelScavenge/psScavenge.hpp Fri Oct 15 09:38:20 2010 +0200
+++ b/hotspot/src/share/vm/gc_implementation/parallelScavenge/psScavenge.hpp Fri Oct 15 02:59:48 2010 -0700
@@ -61,9 +61,10 @@
static HeapWord* _young_generation_boundary; // The lowest address possible for the young_gen.
// This is used to decide if an oop should be scavenged,
// cards should be marked, etc.
- static GrowableArray<markOop>* _preserved_mark_stack; // List of marks to be restored after failed promotion
- static GrowableArray<oop>* _preserved_oop_stack; // List of oops that need their mark restored.
+ static Stack<markOop> _preserved_mark_stack; // List of marks to be restored after failed promotion
+ static Stack<oop> _preserved_oop_stack; // List of oops that need their mark restored.
static CollectorCounters* _counters; // collector performance counters
+ static bool _promotion_failed;
static void clean_up_failed_promotion();
@@ -79,8 +80,7 @@
// Accessors
static int tenuring_threshold() { return _tenuring_threshold; }
static elapsedTimer* accumulated_time() { return &_accumulated_time; }
- static bool promotion_failed()
- { return _preserved_mark_stack != NULL; }
+ static bool promotion_failed() { return _promotion_failed; }
static int consecutive_skipped_scavenges()
{ return _consecutive_skipped_scavenges; }
--- a/hotspot/src/share/vm/gc_implementation/shared/concurrentGCThread.cpp Fri Oct 15 09:38:20 2010 +0200
+++ b/hotspot/src/share/vm/gc_implementation/shared/concurrentGCThread.cpp Fri Oct 15 02:59:48 2010 -0700
@@ -185,7 +185,7 @@
instanceKlassHandle klass (THREAD, k);
instanceHandle thread_oop = klass->allocate_instance_handle(CHECK_NULL);
- const char thread_name[] = "Surrogate Locker Thread (CMS)";
+ const char thread_name[] = "Surrogate Locker Thread (Concurrent GC)";
Handle string = java_lang_String::create_from_str(thread_name, CHECK_NULL);
// Initialize thread_oop to put it into the system threadGroup
--- a/hotspot/src/share/vm/gc_implementation/shared/markSweep.cpp Fri Oct 15 09:38:20 2010 +0200
+++ b/hotspot/src/share/vm/gc_implementation/shared/markSweep.cpp Fri Oct 15 02:59:48 2010 -0700
@@ -25,13 +25,13 @@
#include "incls/_precompiled.incl"
#include "incls/_markSweep.cpp.incl"
-GrowableArray<oop>* MarkSweep::_marking_stack = NULL;
-GrowableArray<ObjArrayTask>* MarkSweep::_objarray_stack = NULL;
-GrowableArray<Klass*>* MarkSweep::_revisit_klass_stack = NULL;
-GrowableArray<DataLayout*>* MarkSweep::_revisit_mdo_stack = NULL;
+Stack<oop> MarkSweep::_marking_stack;
+Stack<DataLayout*> MarkSweep::_revisit_mdo_stack;
+Stack<Klass*> MarkSweep::_revisit_klass_stack;
+Stack<ObjArrayTask> MarkSweep::_objarray_stack;
-GrowableArray<oop>* MarkSweep::_preserved_oop_stack = NULL;
-GrowableArray<markOop>* MarkSweep::_preserved_mark_stack= NULL;
+Stack<oop> MarkSweep::_preserved_oop_stack;
+Stack<markOop> MarkSweep::_preserved_mark_stack;
size_t MarkSweep::_preserved_count = 0;
size_t MarkSweep::_preserved_count_max = 0;
PreservedMark* MarkSweep::_preserved_marks = NULL;
@@ -58,37 +58,42 @@
#endif
void MarkSweep::revisit_weak_klass_link(Klass* k) {
- _revisit_klass_stack->push(k);
+ _revisit_klass_stack.push(k);
}
void MarkSweep::follow_weak_klass_links() {
// All klasses on the revisit stack are marked at this point.
// Update and follow all subklass, sibling and implementor links.
if (PrintRevisitStats) {
- gclog_or_tty->print_cr("#classes in system dictionary = %d", SystemDictionary::number_of_classes());
- gclog_or_tty->print_cr("Revisit klass stack length = %d", _revisit_klass_stack->length());
+ gclog_or_tty->print_cr("#classes in system dictionary = %d",
+ SystemDictionary::number_of_classes());
+ gclog_or_tty->print_cr("Revisit klass stack size = " SIZE_FORMAT,
+ _revisit_klass_stack.size());
}
- for (int i = 0; i < _revisit_klass_stack->length(); i++) {
- _revisit_klass_stack->at(i)->follow_weak_klass_links(&is_alive,&keep_alive);
+ while (!_revisit_klass_stack.is_empty()) {
+ Klass* const k = _revisit_klass_stack.pop();
+ k->follow_weak_klass_links(&is_alive, &keep_alive);
}
follow_stack();
}
void MarkSweep::revisit_mdo(DataLayout* p) {
- _revisit_mdo_stack->push(p);
+ _revisit_mdo_stack.push(p);
}
void MarkSweep::follow_mdo_weak_refs() {
// All strongly reachable oops have been marked at this point;
// we can visit and clear any weak references from MDO's which
// we memoized during the strong marking phase.
- assert(_marking_stack->is_empty(), "Marking stack should be empty");
+ assert(_marking_stack.is_empty(), "Marking stack should be empty");
if (PrintRevisitStats) {
- gclog_or_tty->print_cr("#classes in system dictionary = %d", SystemDictionary::number_of_classes());
- gclog_or_tty->print_cr("Revisit MDO stack length = %d", _revisit_mdo_stack->length());
+ gclog_or_tty->print_cr("#classes in system dictionary = %d",
+ SystemDictionary::number_of_classes());
+ gclog_or_tty->print_cr("Revisit MDO stack size = " SIZE_FORMAT,
+ _revisit_mdo_stack.size());
}
- for (int i = 0; i < _revisit_mdo_stack->length(); i++) {
- _revisit_mdo_stack->at(i)->follow_weak_refs(&is_alive);
+ while (!_revisit_mdo_stack.is_empty()) {
+ _revisit_mdo_stack.pop()->follow_weak_refs(&is_alive);
}
follow_stack();
}
@@ -106,41 +111,37 @@
void MarkSweep::follow_stack() {
do {
- while (!_marking_stack->is_empty()) {
- oop obj = _marking_stack->pop();
+ while (!_marking_stack.is_empty()) {
+ oop obj = _marking_stack.pop();
assert (obj->is_gc_marked(), "p must be marked");
obj->follow_contents();
}
// Process ObjArrays one at a time to avoid marking stack bloat.
- if (!_objarray_stack->is_empty()) {
- ObjArrayTask task = _objarray_stack->pop();
+ if (!_objarray_stack.is_empty()) {
+ ObjArrayTask task = _objarray_stack.pop();
objArrayKlass* const k = (objArrayKlass*)task.obj()->blueprint();
k->oop_follow_contents(task.obj(), task.index());
}
- } while (!_marking_stack->is_empty() || !_objarray_stack->is_empty());
+ } while (!_marking_stack.is_empty() || !_objarray_stack.is_empty());
}
MarkSweep::FollowStackClosure MarkSweep::follow_stack_closure;
void MarkSweep::FollowStackClosure::do_void() { follow_stack(); }
-// We preserve the mark which should be replaced at the end and the location that it
-// will go. Note that the object that this markOop belongs to isn't currently at that
-// address but it will be after phase4
+// We preserve the mark which should be replaced at the end and the location
+// that it will go. Note that the object that this markOop belongs to isn't
+// currently at that address but it will be after phase4
void MarkSweep::preserve_mark(oop obj, markOop mark) {
- // we try to store preserved marks in the to space of the new generation since this
- // is storage which should be available. Most of the time this should be sufficient
- // space for the marks we need to preserve but if it isn't we fall back in using
- // GrowableArrays to keep track of the overflow.
+ // We try to store preserved marks in the to space of the new generation since
+ // this is storage which should be available. Most of the time this should be
+ // sufficient space for the marks we need to preserve but if it isn't we fall
+ // back to using Stacks to keep track of the overflow.
if (_preserved_count < _preserved_count_max) {
_preserved_marks[_preserved_count++].init(obj, mark);
} else {
- if (_preserved_mark_stack == NULL) {
- _preserved_mark_stack = new (ResourceObj::C_HEAP) GrowableArray<markOop>(40, true);
- _preserved_oop_stack = new (ResourceObj::C_HEAP) GrowableArray<oop>(40, true);
- }
- _preserved_mark_stack->push(mark);
- _preserved_oop_stack->push(obj);
+ _preserved_mark_stack.push(mark);
+ _preserved_oop_stack.push(obj);
}
}
@@ -151,8 +152,7 @@
void MarkSweep::AdjustPointerClosure::do_oop(narrowOop* p) { adjust_pointer(p, _is_root); }
void MarkSweep::adjust_marks() {
- assert(_preserved_oop_stack == NULL ||
- _preserved_oop_stack->length() == _preserved_mark_stack->length(),
+ assert( _preserved_oop_stack.size() == _preserved_mark_stack.size(),
"inconsistent preserved oop stacks");
// adjust the oops we saved earlier
@@ -161,21 +161,19 @@
}
// deal with the overflow stack
- if (_preserved_oop_stack) {
- for (int i = 0; i < _preserved_oop_stack->length(); i++) {
- oop* p = _preserved_oop_stack->adr_at(i);
- adjust_pointer(p);
- }
+ StackIterator<oop> iter(_preserved_oop_stack);
+ while (!iter.is_empty()) {
+ oop* p = iter.next_addr();
+ adjust_pointer(p);
}
}
void MarkSweep::restore_marks() {
- assert(_preserved_oop_stack == NULL ||
- _preserved_oop_stack->length() == _preserved_mark_stack->length(),
+ assert(_preserved_oop_stack.size() == _preserved_mark_stack.size(),
"inconsistent preserved oop stacks");
if (PrintGC && Verbose) {
- gclog_or_tty->print_cr("Restoring %d marks", _preserved_count +
- (_preserved_oop_stack ? _preserved_oop_stack->length() : 0));
+ gclog_or_tty->print_cr("Restoring %d marks",
+ _preserved_count + _preserved_oop_stack.size());
}
// restore the marks we saved earlier
@@ -184,12 +182,10 @@
}
// deal with the overflow
- if (_preserved_oop_stack) {
- for (int i = 0; i < _preserved_oop_stack->length(); i++) {
- oop obj = _preserved_oop_stack->at(i);
- markOop mark = _preserved_mark_stack->at(i);
- obj->set_mark(mark);
- }
+ while (!_preserved_oop_stack.is_empty()) {
+ oop obj = _preserved_oop_stack.pop();
+ markOop mark = _preserved_mark_stack.pop();
+ obj->set_mark(mark);
}
}
--- a/hotspot/src/share/vm/gc_implementation/shared/markSweep.hpp Fri Oct 15 09:38:20 2010 +0200
+++ b/hotspot/src/share/vm/gc_implementation/shared/markSweep.hpp Fri Oct 15 02:59:48 2010 -0700
@@ -104,23 +104,22 @@
friend class KeepAliveClosure;
friend class VM_MarkSweep;
friend void marksweep_init();
- friend class DataLayout;
//
// Vars
//
protected:
// Traversal stacks used during phase1
- static GrowableArray<oop>* _marking_stack;
- static GrowableArray<ObjArrayTask>* _objarray_stack;
+ static Stack<oop> _marking_stack;
+ static Stack<ObjArrayTask> _objarray_stack;
// Stack for live klasses to revisit at end of marking phase
- static GrowableArray<Klass*>* _revisit_klass_stack;
+ static Stack<Klass*> _revisit_klass_stack;
// Set (stack) of MDO's to revisit at end of marking phase
- static GrowableArray<DataLayout*>* _revisit_mdo_stack;
+ static Stack<DataLayout*> _revisit_mdo_stack;
// Space for storing/restoring mark word
- static GrowableArray<markOop>* _preserved_mark_stack;
- static GrowableArray<oop>* _preserved_oop_stack;
+ static Stack<markOop> _preserved_mark_stack;
+ static Stack<oop> _preserved_oop_stack;
static size_t _preserved_count;
static size_t _preserved_count_max;
static PreservedMark* _preserved_marks;
--- a/hotspot/src/share/vm/gc_implementation/shared/markSweep.inline.hpp Fri Oct 15 09:38:20 2010 +0200
+++ b/hotspot/src/share/vm/gc_implementation/shared/markSweep.inline.hpp Fri Oct 15 02:59:48 2010 -0700
@@ -72,7 +72,7 @@
oop obj = oopDesc::decode_heap_oop_not_null(heap_oop);
if (!obj->mark()->is_marked()) {
mark_object(obj);
- _marking_stack->push(obj);
+ _marking_stack.push(obj);
}
}
}
@@ -80,7 +80,7 @@
void MarkSweep::push_objarray(oop obj, size_t index) {
ObjArrayTask task(obj, index);
assert(task.is_valid(), "bad ObjArrayTask");
- _objarray_stack->push(task);
+ _objarray_stack.push(task);
}
template <class T> inline void MarkSweep::adjust_pointer(T* p, bool isroot) {
--- a/hotspot/src/share/vm/gc_interface/collectedHeap.cpp Fri Oct 15 09:38:20 2010 +0200
+++ b/hotspot/src/share/vm/gc_interface/collectedHeap.cpp Fri Oct 15 02:59:48 2010 -0700
@@ -1,5 +1,5 @@
/*
- * Copyright (c) 2001, 2009, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2001, 2010, Oracle and/or its affiliates. All rights reserved.
* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
*
* This code is free software; you can redistribute it and/or modify it
@@ -34,7 +34,9 @@
// Memory state functions.
-CollectedHeap::CollectedHeap()
+
+CollectedHeap::CollectedHeap() : _n_par_threads(0)
+
{
const size_t max_len = size_t(arrayOopDesc::max_array_length(T_INT));
const size_t elements_per_word = HeapWordSize / sizeof(jint);
--- a/hotspot/src/share/vm/gc_interface/collectedHeap.hpp Fri Oct 15 09:38:20 2010 +0200
+++ b/hotspot/src/share/vm/gc_interface/collectedHeap.hpp Fri Oct 15 02:59:48 2010 -0700
@@ -59,6 +59,8 @@
MemRegion _reserved;
BarrierSet* _barrier_set;
bool _is_gc_active;
+ int _n_par_threads;
+
unsigned int _total_collections; // ... started
unsigned int _total_full_collections; // ... started
NOT_PRODUCT(volatile size_t _promotion_failure_alot_count;)
@@ -293,6 +295,12 @@
}
GCCause::Cause gc_cause() { return _gc_cause; }
+ // Number of threads currently working on GC tasks.
+ int n_par_threads() { return _n_par_threads; }
+
+ // May be overridden to set additional parallelism.
+ virtual void set_par_threads(int t) { _n_par_threads = t; };
+
// Preload classes into the shared portion of the heap, and then dump
// that data to a file so that it can be loaded directly by another
// VM (then terminate).
@@ -606,6 +614,14 @@
return (CIFireOOMAt > 1 && _fire_out_of_memory_count >= CIFireOOMAt);
}
#endif
+
+ public:
+ // This is a convenience method that is used in cases where
+ // the actual number of GC worker threads is not pertinent but
+ // only whether there more than 0. Use of this method helps
+ // reduce the occurrence of ParallelGCThreads to uses where the
+ // actual number may be germane.
+ static bool use_parallel_gc_threads() { return ParallelGCThreads > 0; }
};
// Class to set and reset the GC cause for a CollectedHeap.
--- a/hotspot/src/share/vm/includeDB_core Fri Oct 15 09:38:20 2010 +0200
+++ b/hotspot/src/share/vm/includeDB_core Fri Oct 15 02:59:48 2010 -0700
@@ -1437,12 +1437,14 @@
defNewGeneration.cpp referencePolicy.hpp
defNewGeneration.cpp space.inline.hpp
defNewGeneration.cpp spaceDecorator.hpp
+defNewGeneration.cpp stack.inline.hpp
defNewGeneration.cpp thread_<os_family>.inline.hpp
defNewGeneration.hpp ageTable.hpp
defNewGeneration.hpp cSpaceCounters.hpp
defNewGeneration.hpp generation.inline.hpp
defNewGeneration.hpp generationCounters.hpp
+defNewGeneration.hpp stack.hpp
defNewGeneration.inline.hpp cardTableRS.hpp
defNewGeneration.inline.hpp defNewGeneration.hpp
@@ -3461,6 +3463,7 @@
permGen.hpp generation.hpp
permGen.hpp handles.hpp
permGen.hpp iterator.hpp
+permGen.hpp mutexLocker.hpp
permGen.hpp virtualspace.hpp
placeholders.cpp fieldType.hpp
@@ -3871,6 +3874,10 @@
specialized_oop_closures.hpp atomic.hpp
+stack.hpp allocation.inline.hpp
+
+stack.inline.hpp stack.hpp
+
stackMapFrame.cpp globalDefinitions.hpp
stackMapFrame.cpp handles.inline.hpp
stackMapFrame.cpp oop.inline.hpp
@@ -4115,6 +4122,7 @@
taskqueue.cpp debug.hpp
taskqueue.cpp oop.inline.hpp
taskqueue.cpp os.hpp
+taskqueue.cpp stack.inline.hpp
taskqueue.cpp taskqueue.hpp
taskqueue.cpp thread_<os_family>.inline.hpp
@@ -4122,6 +4130,7 @@
taskqueue.hpp allocation.inline.hpp
taskqueue.hpp mutex.hpp
taskqueue.hpp orderAccess_<os_arch>.inline.hpp
+taskqueue.hpp stack.hpp
templateInterpreter.cpp interpreter.hpp
templateInterpreter.cpp interpreterGenerator.hpp
@@ -4741,6 +4750,7 @@
workgroup.cpp os.hpp
workgroup.cpp workgroup.hpp
+workgroup.hpp taskqueue.hpp
workgroup.hpp thread_<os_family>.inline.hpp
xmlstream.cpp allocation.hpp
--- a/hotspot/src/share/vm/memory/allocation.hpp Fri Oct 15 09:38:20 2010 +0200
+++ b/hotspot/src/share/vm/memory/allocation.hpp Fri Oct 15 02:59:48 2010 -0700
@@ -289,16 +289,17 @@
// One of the following macros must be used when allocating
// an array or object from an arena
-#define NEW_ARENA_ARRAY(arena, type, size)\
- (type*) arena->Amalloc((size) * sizeof(type))
+#define NEW_ARENA_ARRAY(arena, type, size) \
+ (type*) (arena)->Amalloc((size) * sizeof(type))
-#define REALLOC_ARENA_ARRAY(arena, type, old, old_size, new_size)\
- (type*) arena->Arealloc((char*)(old), (old_size) * sizeof(type), (new_size) * sizeof(type) )
+#define REALLOC_ARENA_ARRAY(arena, type, old, old_size, new_size) \
+ (type*) (arena)->Arealloc((char*)(old), (old_size) * sizeof(type), \
+ (new_size) * sizeof(type) )
-#define FREE_ARENA_ARRAY(arena, type, old, size)\
- arena->Afree((char*)(old), (size) * sizeof(type))
+#define FREE_ARENA_ARRAY(arena, type, old, size) \
+ (arena)->Afree((char*)(old), (size) * sizeof(type))
-#define NEW_ARENA_OBJ(arena, type)\
+#define NEW_ARENA_OBJ(arena, type) \
NEW_ARENA_ARRAY(arena, type, 1)
--- a/hotspot/src/share/vm/memory/defNewGeneration.cpp Fri Oct 15 09:38:20 2010 +0200
+++ b/hotspot/src/share/vm/memory/defNewGeneration.cpp Fri Oct 15 02:59:48 2010 -0700
@@ -87,9 +87,7 @@
_gch->oop_since_save_marks_iterate(_level, _scan_cur_or_nonheap,
_scan_older);
} while (!_gch->no_allocs_since_save_marks(_level));
- guarantee(_gen->promo_failure_scan_stack() == NULL
- || _gen->promo_failure_scan_stack()->length() == 0,
- "Failed to finish scan");
+ guarantee(_gen->promo_failure_scan_is_complete(), "Failed to finish scan");
}
ScanClosure::ScanClosure(DefNewGeneration* g, bool gc_barrier) :
@@ -130,9 +128,6 @@
int level,
const char* policy)
: Generation(rs, initial_size, level),
- _objs_with_preserved_marks(NULL),
- _preserved_marks_of_objs(NULL),
- _promo_failure_scan_stack(NULL),
_promo_failure_drain_in_progress(false),
_should_allocate_from_space(false)
{
@@ -604,12 +599,8 @@
} else {
assert(HandlePromotionFailure,
"Should not be here unless promotion failure handling is on");
- assert(_promo_failure_scan_stack != NULL &&
- _promo_failure_scan_stack->length() == 0, "post condition");
-
- // deallocate stack and it's elements
- delete _promo_failure_scan_stack;
- _promo_failure_scan_stack = NULL;
+ assert(_promo_failure_scan_stack.is_empty(), "post condition");
+ _promo_failure_scan_stack.clear(true); // Clear cached segments.
remove_forwarding_pointers();
if (PrintGCDetails) {
@@ -620,7 +611,7 @@
// case there can be live objects in to-space
// as a result of a partial evacuation of eden
// and from-space.
- swap_spaces(); // For the sake of uniformity wrt ParNewGeneration::collect().
+ swap_spaces(); // For uniformity wrt ParNewGeneration.
from()->set_next_compaction_space(to());
gch->set_incremental_collection_will_fail();
@@ -653,34 +644,23 @@
RemoveForwardPointerClosure rspc;
eden()->object_iterate(&rspc);
from()->object_iterate(&rspc);
+
// Now restore saved marks, if any.
- if (_objs_with_preserved_marks != NULL) {
- assert(_preserved_marks_of_objs != NULL, "Both or none.");
- assert(_objs_with_preserved_marks->length() ==
- _preserved_marks_of_objs->length(), "Both or none.");
- for (int i = 0; i < _objs_with_preserved_marks->length(); i++) {
- oop obj = _objs_with_preserved_marks->at(i);
- markOop m = _preserved_marks_of_objs->at(i);
- obj->set_mark(m);
- }
- delete _objs_with_preserved_marks;
- delete _preserved_marks_of_objs;
- _objs_with_preserved_marks = NULL;
- _preserved_marks_of_objs = NULL;
+ assert(_objs_with_preserved_marks.size() == _preserved_marks_of_objs.size(),
+ "should be the same");
+ while (!_objs_with_preserved_marks.is_empty()) {
+ oop obj = _objs_with_preserved_marks.pop();
+ markOop m = _preserved_marks_of_objs.pop();
+ obj->set_mark(m);
}
+ _objs_with_preserved_marks.clear(true);
+ _preserved_marks_of_objs.clear(true);
}
void DefNewGeneration::preserve_mark_if_necessary(oop obj, markOop m) {
if (m->must_be_preserved_for_promotion_failure(obj)) {
- if (_objs_with_preserved_marks == NULL) {
- assert(_preserved_marks_of_objs == NULL, "Both or none.");
- _objs_with_preserved_marks = new (ResourceObj::C_HEAP)
- GrowableArray<oop>(PreserveMarkStackSize, true);
- _preserved_marks_of_objs = new (ResourceObj::C_HEAP)
- GrowableArray<markOop>(PreserveMarkStackSize, true);
- }
- _objs_with_preserved_marks->push(obj);
- _preserved_marks_of_objs->push(m);
+ _objs_with_preserved_marks.push(obj);
+ _preserved_marks_of_objs.push(m);
}
}
@@ -695,7 +675,7 @@
old->forward_to(old);
_promotion_failed = true;
- push_on_promo_failure_scan_stack(old);
+ _promo_failure_scan_stack.push(old);
if (!_promo_failure_drain_in_progress) {
// prevent recursion in copy_to_survivor_space()
@@ -748,20 +728,9 @@
return obj;
}
-void DefNewGeneration::push_on_promo_failure_scan_stack(oop obj) {
- if (_promo_failure_scan_stack == NULL) {
- _promo_failure_scan_stack = new (ResourceObj::C_HEAP)
- GrowableArray<oop>(40, true);
- }
-
- _promo_failure_scan_stack->push(obj);
-}
-
void DefNewGeneration::drain_promo_failure_scan_stack() {
- assert(_promo_failure_scan_stack != NULL, "precondition");
-
- while (_promo_failure_scan_stack->length() > 0) {
- oop obj = _promo_failure_scan_stack->pop();
+ while (!_promo_failure_scan_stack.is_empty()) {
+ oop obj = _promo_failure_scan_stack.pop();
obj->oop_iterate(_promo_failure_scan_stack_closure);
}
}
--- a/hotspot/src/share/vm/memory/defNewGeneration.hpp Fri Oct 15 09:38:20 2010 +0200
+++ b/hotspot/src/share/vm/memory/defNewGeneration.hpp Fri Oct 15 02:59:48 2010 -0700
@@ -77,10 +77,10 @@
// word being overwritten with a self-forwarding-pointer.
void preserve_mark_if_necessary(oop obj, markOop m);
- // When one is non-null, so is the other. Together, they each pair is
- // an object with a preserved mark, and its mark value.
- GrowableArray<oop>* _objs_with_preserved_marks;
- GrowableArray<markOop>* _preserved_marks_of_objs;
+ // Together, these keep <object with a preserved mark, mark value> pairs.
+ // They should always contain the same number of elements.
+ Stack<oop> _objs_with_preserved_marks;
+ Stack<markOop> _preserved_marks_of_objs;
// Returns true if the collection can be safely attempted.
// If this method returns false, a collection is not
@@ -94,11 +94,7 @@
_promo_failure_scan_stack_closure = scan_stack_closure;
}
- GrowableArray<oop>* _promo_failure_scan_stack;
- GrowableArray<oop>* promo_failure_scan_stack() const {
- return _promo_failure_scan_stack;
- }
- void push_on_promo_failure_scan_stack(oop);
+ Stack<oop> _promo_failure_scan_stack;
void drain_promo_failure_scan_stack(void);
bool _promo_failure_drain_in_progress;
@@ -184,8 +180,6 @@
void do_void();
};
- class FastEvacuateFollowersClosure;
- friend class FastEvacuateFollowersClosure;
class FastEvacuateFollowersClosure: public VoidClosure {
GenCollectedHeap* _gch;
int _level;
@@ -336,6 +330,10 @@
void verify(bool allow_dirty);
+ bool promo_failure_scan_is_complete() const {
+ return _promo_failure_scan_stack.is_empty();
+ }
+
protected:
// If clear_space is true, clear the survivor spaces. Eden is
// cleared if the minimum size of eden is 0. If mangle_space
--- a/hotspot/src/share/vm/memory/genCollectedHeap.cpp Fri Oct 15 09:38:20 2010 +0200
+++ b/hotspot/src/share/vm/memory/genCollectedHeap.cpp Fri Oct 15 02:59:48 2010 -0700
@@ -676,7 +676,7 @@
void GenCollectedHeap::set_par_threads(int t) {
SharedHeap::set_par_threads(t);
- _gen_process_strong_tasks->set_par_threads(t);
+ _gen_process_strong_tasks->set_n_threads(t);
}
class AssertIsPermClosure: public OopClosure {
--- a/hotspot/src/share/vm/memory/genCollectedHeap.hpp Fri Oct 15 09:38:20 2010 +0200
+++ b/hotspot/src/share/vm/memory/genCollectedHeap.hpp Fri Oct 15 02:59:48 2010 -0700
@@ -1,5 +1,5 @@
/*
- * Copyright (c) 2000, 2009, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2000, 2010, Oracle and/or its affiliates. All rights reserved.
* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
*
* This code is free software; you can redistribute it and/or modify it
@@ -74,6 +74,7 @@
// Data structure for claiming the (potentially) parallel tasks in
// (gen-specific) strong roots processing.
SubTasksDone* _gen_process_strong_tasks;
+ SubTasksDone* gen_process_strong_tasks() { return _gen_process_strong_tasks; }
// In block contents verification, the number of header words to skip
NOT_PRODUCT(static size_t _skip_header_HeapWords;)
--- a/hotspot/src/share/vm/memory/genMarkSweep.cpp Fri Oct 15 09:38:20 2010 +0200
+++ b/hotspot/src/share/vm/memory/genMarkSweep.cpp Fri Oct 15 02:59:48 2010 -0700
@@ -161,17 +161,6 @@
_preserved_marks = (PreservedMark*)scratch;
_preserved_count = 0;
- _preserved_mark_stack = NULL;
- _preserved_oop_stack = NULL;
-
- _marking_stack = new (ResourceObj::C_HEAP) GrowableArray<oop>(4000, true);
- _objarray_stack = new (ResourceObj::C_HEAP) GrowableArray<ObjArrayTask>(50, true);
-
- int size = SystemDictionary::number_of_classes() * 2;
- _revisit_klass_stack = new (ResourceObj::C_HEAP) GrowableArray<Klass*>(size, true);
- // (#klass/k)^2 for k ~ 10 appears to be a better fit, but this will have to do for
- // now until we have had a chance to investigate a more optimal setting.
- _revisit_mdo_stack = new (ResourceObj::C_HEAP) GrowableArray<DataLayout*>(2*size, true);
#ifdef VALIDATE_MARK_SWEEP
if (ValidateMarkSweep) {
@@ -206,17 +195,12 @@
gch->release_scratch();
}
- if (_preserved_oop_stack) {
- delete _preserved_mark_stack;
- _preserved_mark_stack = NULL;
- delete _preserved_oop_stack;
- _preserved_oop_stack = NULL;
- }
-
- delete _marking_stack;
- delete _objarray_stack;
- delete _revisit_klass_stack;
- delete _revisit_mdo_stack;
+ _preserved_mark_stack.clear(true);
+ _preserved_oop_stack.clear(true);
+ _marking_stack.clear();
+ _objarray_stack.clear(true);
+ _revisit_klass_stack.clear(true);
+ _revisit_mdo_stack.clear(true);
#ifdef VALIDATE_MARK_SWEEP
if (ValidateMarkSweep) {
@@ -274,17 +258,17 @@
// Update subklass/sibling/implementor links of live klasses
follow_weak_klass_links();
- assert(_marking_stack->is_empty(), "just drained");
+ assert(_marking_stack.is_empty(), "just drained");
// Visit memoized MDO's and clear any unmarked weak refs
follow_mdo_weak_refs();
- assert(_marking_stack->is_empty(), "just drained");
+ assert(_marking_stack.is_empty(), "just drained");
// Visit symbol and interned string tables and delete unmarked oops
SymbolTable::unlink(&is_alive);
StringTable::unlink(&is_alive);
- assert(_marking_stack->is_empty(), "stack should be empty by now");
+ assert(_marking_stack.is_empty(), "stack should be empty by now");
}
--- a/hotspot/src/share/vm/memory/permGen.cpp Fri Oct 15 09:38:20 2010 +0200
+++ b/hotspot/src/share/vm/memory/permGen.cpp Fri Oct 15 02:59:48 2010 -0700
@@ -1,5 +1,5 @@
/*
- * Copyright (c) 2000, 2009, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2000, 2010, Oracle and/or its affiliates. All rights reserved.
* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
*
* This code is free software; you can redistribute it and/or modify it
@@ -25,6 +25,17 @@
#include "incls/_precompiled.incl"
#include "incls/_permGen.cpp.incl"
+HeapWord* PermGen::request_expand_and_allocate(Generation* gen, size_t size,
+ GCCause::Cause prev_cause) {
+ if (gen->capacity() < _capacity_expansion_limit ||
+ prev_cause != GCCause::_no_gc || UseG1GC) { // last disjunct is a temporary hack for G1
+ return gen->expand_and_allocate(size, false);
+ }
+ // We have reached the limit of capacity expansion where
+ // we will not expand further until a GC is done; request denied.
+ return NULL;
+}
+
HeapWord* PermGen::mem_allocate_in_gen(size_t size, Generation* gen) {
GCCause::Cause next_cause = GCCause::_permanent_generation_full;
GCCause::Cause prev_cause = GCCause::_no_gc;
@@ -37,10 +48,14 @@
if ((obj = gen->allocate(size, false)) != NULL) {
return obj;
}
- if (gen->capacity() < _capacity_expansion_limit ||
- prev_cause != GCCause::_no_gc) {
- obj = gen->expand_and_allocate(size, false);
- }
+ // Attempt to expand and allocate the requested space:
+ // specific subtypes may use specific policy to either expand
+ // or not. The default policy (see above) is to expand until
+ // _capacity_expansion_limit, and no further unless a GC is done.
+ // Concurrent collectors may decide to kick off a concurrent
+ // collection under appropriate conditions.
+ obj = request_expand_and_allocate(gen, size, prev_cause);
+
if (obj != NULL || prev_cause == GCCause::_last_ditch_collection) {
return obj;
}
@@ -119,5 +134,5 @@
if (_gen->capacity() > desired_capacity) {
_gen->shrink(_gen->capacity() - desired_capacity);
}
- _capacity_expansion_limit = _gen->capacity() + MaxPermHeapExpansion;
+ set_capacity_expansion_limit(_gen->capacity() + MaxPermHeapExpansion);
}
--- a/hotspot/src/share/vm/memory/permGen.hpp Fri Oct 15 09:38:20 2010 +0200
+++ b/hotspot/src/share/vm/memory/permGen.hpp Fri Oct 15 02:59:48 2010 -0700
@@ -1,5 +1,5 @@
/*
- * Copyright (c) 2000, 2008, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2000, 2010, Oracle and/or its affiliates. All rights reserved.
* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
*
* This code is free software; you can redistribute it and/or modify it
@@ -30,15 +30,26 @@
class GenRemSet;
class CSpaceCounters;
-// PermGen models the part of the heap
+// PermGen models the part of the heap used to allocate class meta-data.
class PermGen : public CHeapObj {
friend class VMStructs;
protected:
size_t _capacity_expansion_limit; // maximum expansion allowed without a
// full gc occurring
+ void set_capacity_expansion_limit(size_t limit) {
+ assert_locked_or_safepoint(Heap_lock);
+ _capacity_expansion_limit = limit;
+ }
HeapWord* mem_allocate_in_gen(size_t size, Generation* gen);
+ // Along with mem_allocate_in_gen() above, implements policy for
+ // "scheduling" allocation/expansion/collection of the perm gen.
+ // The virtual method request_...() below can be overridden by
+ // subtypes that want to implement a different expansion/collection
+ // policy from the default provided.
+ virtual HeapWord* request_expand_and_allocate(Generation* gen, size_t size,
+ GCCause::Cause prev_cause);
public:
enum Name {
--- a/hotspot/src/share/vm/memory/referenceProcessor.cpp Fri Oct 15 09:38:20 2010 +0200
+++ b/hotspot/src/share/vm/memory/referenceProcessor.cpp Fri Oct 15 02:59:48 2010 -0700
@@ -1,5 +1,5 @@
/*
- * Copyright (c) 2001, 2009, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2001, 2010, Oracle and/or its affiliates. All rights reserved.
* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
*
* This code is free software; you can redistribute it and/or modify it
@@ -137,16 +137,17 @@
_discovery_is_atomic = atomic_discovery;
_discovery_is_mt = mt_discovery;
_num_q = mt_degree;
- _discoveredSoftRefs = NEW_C_HEAP_ARRAY(DiscoveredList, _num_q * subclasses_of_ref);
+ _max_num_q = mt_degree;
+ _discoveredSoftRefs = NEW_C_HEAP_ARRAY(DiscoveredList, _max_num_q * subclasses_of_ref);
if (_discoveredSoftRefs == NULL) {
vm_exit_during_initialization("Could not allocated RefProc Array");
}
- _discoveredWeakRefs = &_discoveredSoftRefs[_num_q];
- _discoveredFinalRefs = &_discoveredWeakRefs[_num_q];
- _discoveredPhantomRefs = &_discoveredFinalRefs[_num_q];
+ _discoveredWeakRefs = &_discoveredSoftRefs[_max_num_q];
+ _discoveredFinalRefs = &_discoveredWeakRefs[_max_num_q];
+ _discoveredPhantomRefs = &_discoveredFinalRefs[_max_num_q];
assert(sentinel_ref() != NULL, "_sentinelRef is NULL");
// Initialized all entries to _sentinelRef
- for (int i = 0; i < _num_q * subclasses_of_ref; i++) {
+ for (int i = 0; i < _max_num_q * subclasses_of_ref; i++) {
_discoveredSoftRefs[i].set_head(sentinel_ref());
_discoveredSoftRefs[i].set_length(0);
}
@@ -159,7 +160,7 @@
#ifndef PRODUCT
void ReferenceProcessor::verify_no_references_recorded() {
guarantee(!_discovering_refs, "Discovering refs?");
- for (int i = 0; i < _num_q * subclasses_of_ref; i++) {
+ for (int i = 0; i < _max_num_q * subclasses_of_ref; i++) {
guarantee(_discoveredSoftRefs[i].empty(),
"Found non-empty discovered list");
}
@@ -167,7 +168,11 @@
#endif
void ReferenceProcessor::weak_oops_do(OopClosure* f) {
- for (int i = 0; i < _num_q * subclasses_of_ref; i++) {
+ // Should this instead be
+ // for (int i = 0; i < subclasses_of_ref; i++_ {
+ // for (int j = 0; j < _num_q; j++) {
+ // int index = i * _max_num_q + j;
+ for (int i = 0; i < _max_num_q * subclasses_of_ref; i++) {
if (UseCompressedOops) {
f->do_oop((narrowOop*)_discoveredSoftRefs[i].adr_head());
} else {
@@ -395,7 +400,15 @@
assert(work_id < (unsigned int)_ref_processor.num_q(), "Index out-of-bounds");
// Simplest first cut: static partitioning.
int index = work_id;
- for (int j = 0; j < subclasses_of_ref; j++, index += _n_queues) {
+ // The increment on "index" must correspond to the maximum number of queues
+ // (n_queues) with which that ReferenceProcessor was created. That
+ // is because of the "clever" way the discovered references lists were
+ // allocated and are indexed into. That number is ParallelGCThreads
+ // currently. Assert that.
+ assert(_n_queues == (int) ParallelGCThreads, "Different number not expected");
+ for (int j = 0;
+ j < subclasses_of_ref;
+ j++, index += _n_queues) {
_ref_processor.enqueue_discovered_reflist(
_refs_lists[index], _pending_list_addr);
_refs_lists[index].set_head(_sentinel_ref);
@@ -410,11 +423,11 @@
if (_processing_is_mt && task_executor != NULL) {
// Parallel code
RefProcEnqueueTask tsk(*this, _discoveredSoftRefs,
- pending_list_addr, sentinel_ref(), _num_q);
+ pending_list_addr, sentinel_ref(), _max_num_q);
task_executor->execute(tsk);
} else {
// Serial code: call the parent class's implementation
- for (int i = 0; i < _num_q * subclasses_of_ref; i++) {
+ for (int i = 0; i < _max_num_q * subclasses_of_ref; i++) {
enqueue_discovered_reflist(_discoveredSoftRefs[i], pending_list_addr);
_discoveredSoftRefs[i].set_head(sentinel_ref());
_discoveredSoftRefs[i].set_length(0);
@@ -614,8 +627,9 @@
complete_gc->do_void();
NOT_PRODUCT(
if (PrintGCDetails && TraceReferenceGC) {
- gclog_or_tty->print(" Dropped %d dead Refs out of %d "
- "discovered Refs by policy ", iter.removed(), iter.processed());
+ gclog_or_tty->print_cr(" Dropped %d dead Refs out of %d "
+ "discovered Refs by policy list " INTPTR_FORMAT,
+ iter.removed(), iter.processed(), (address)refs_list.head());
}
)
}
@@ -651,8 +665,9 @@
}
NOT_PRODUCT(
if (PrintGCDetails && TraceReferenceGC) {
- gclog_or_tty->print(" Dropped %d active Refs out of %d "
- "Refs in discovered list ", iter.removed(), iter.processed());
+ gclog_or_tty->print_cr(" Dropped %d active Refs out of %d "
+ "Refs in discovered list " INTPTR_FORMAT,
+ iter.removed(), iter.processed(), (address)refs_list.head());
}
)
}
@@ -689,8 +704,9 @@
complete_gc->do_void();
NOT_PRODUCT(
if (PrintGCDetails && TraceReferenceGC) {
- gclog_or_tty->print(" Dropped %d active Refs out of %d "
- "Refs in discovered list ", iter.removed(), iter.processed());
+ gclog_or_tty->print_cr(" Dropped %d active Refs out of %d "
+ "Refs in discovered list " INTPTR_FORMAT,
+ iter.removed(), iter.processed(), (address)refs_list.head());
}
)
}
@@ -704,6 +720,7 @@
BoolObjectClosure* is_alive,
OopClosure* keep_alive,
VoidClosure* complete_gc) {
+ ResourceMark rm;
DiscoveredListIterator iter(refs_list, keep_alive, is_alive);
while (iter.has_next()) {
iter.update_discovered();
@@ -743,8 +760,8 @@
void ReferenceProcessor::abandon_partial_discovery() {
// loop over the lists
- for (int i = 0; i < _num_q * subclasses_of_ref; i++) {
- if (TraceReferenceGC && PrintGCDetails && ((i % _num_q) == 0)) {
+ for (int i = 0; i < _max_num_q * subclasses_of_ref; i++) {
+ if (TraceReferenceGC && PrintGCDetails && ((i % _max_num_q) == 0)) {
gclog_or_tty->print_cr(
"\nAbandoning %s discovered list",
list_name(i));
@@ -766,7 +783,9 @@
OopClosure& keep_alive,
VoidClosure& complete_gc)
{
- _ref_processor.process_phase1(_refs_lists[i], _policy,
+ Thread* thr = Thread::current();
+ int refs_list_index = ((WorkerThread*)thr)->id();
+ _ref_processor.process_phase1(_refs_lists[refs_list_index], _policy,
&is_alive, &keep_alive, &complete_gc);
}
private:
@@ -802,6 +821,11 @@
OopClosure& keep_alive,
VoidClosure& complete_gc)
{
+ // Don't use "refs_list_index" calculated in this way because
+ // balance_queues() has moved the Ref's into the first n queues.
+ // Thread* thr = Thread::current();
+ // int refs_list_index = ((WorkerThread*)thr)->id();
+ // _ref_processor.process_phase3(_refs_lists[refs_list_index], _clear_referent,
_ref_processor.process_phase3(_refs_lists[i], _clear_referent,
&is_alive, &keep_alive, &complete_gc);
}
@@ -810,23 +834,47 @@
};
// Balances reference queues.
+// Move entries from all queues[0, 1, ..., _max_num_q-1] to
+// queues[0, 1, ..., _num_q-1] because only the first _num_q
+// corresponding to the active workers will be processed.
void ReferenceProcessor::balance_queues(DiscoveredList ref_lists[])
{
// calculate total length
size_t total_refs = 0;
- for (int i = 0; i < _num_q; ++i) {
+ if (TraceReferenceGC && PrintGCDetails) {
+ gclog_or_tty->print_cr("\nBalance ref_lists ");
+ }
+
+ for (int i = 0; i < _max_num_q; ++i) {
total_refs += ref_lists[i].length();
+ if (TraceReferenceGC && PrintGCDetails) {
+ gclog_or_tty->print("%d ", ref_lists[i].length());
+ }
+ }
+ if (TraceReferenceGC && PrintGCDetails) {
+ gclog_or_tty->print_cr(" = %d", total_refs);
}
size_t avg_refs = total_refs / _num_q + 1;
int to_idx = 0;
- for (int from_idx = 0; from_idx < _num_q; from_idx++) {
- while (ref_lists[from_idx].length() > avg_refs) {
+ for (int from_idx = 0; from_idx < _max_num_q; from_idx++) {
+ bool move_all = false;
+ if (from_idx >= _num_q) {
+ move_all = ref_lists[from_idx].length() > 0;
+ }
+ while ((ref_lists[from_idx].length() > avg_refs) ||
+ move_all) {
assert(to_idx < _num_q, "Sanity Check!");
if (ref_lists[to_idx].length() < avg_refs) {
// move superfluous refs
- size_t refs_to_move =
- MIN2(ref_lists[from_idx].length() - avg_refs,
- avg_refs - ref_lists[to_idx].length());
+ size_t refs_to_move;
+ // Move all the Ref's if the from queue will not be processed.
+ if (move_all) {
+ refs_to_move = MIN2(ref_lists[from_idx].length(),
+ avg_refs - ref_lists[to_idx].length());
+ } else {
+ refs_to_move = MIN2(ref_lists[from_idx].length() - avg_refs,
+ avg_refs - ref_lists[to_idx].length());
+ }
oop move_head = ref_lists[from_idx].head();
oop move_tail = move_head;
oop new_head = move_head;
@@ -840,11 +888,35 @@
ref_lists[to_idx].inc_length(refs_to_move);
ref_lists[from_idx].set_head(new_head);
ref_lists[from_idx].dec_length(refs_to_move);
+ if (ref_lists[from_idx].length() == 0) {
+ break;
+ }
} else {
- ++to_idx;
+ to_idx = (to_idx + 1) % _num_q;
}
}
}
+#ifdef ASSERT
+ size_t balanced_total_refs = 0;
+ for (int i = 0; i < _max_num_q; ++i) {
+ balanced_total_refs += ref_lists[i].length();
+ if (TraceReferenceGC && PrintGCDetails) {
+ gclog_or_tty->print("%d ", ref_lists[i].length());
+ }
+ }
+ if (TraceReferenceGC && PrintGCDetails) {
+ gclog_or_tty->print_cr(" = %d", balanced_total_refs);
+ gclog_or_tty->flush();
+ }
+ assert(total_refs == balanced_total_refs, "Balancing was incomplete");
+#endif
+}
+
+void ReferenceProcessor::balance_all_queues() {
+ balance_queues(_discoveredSoftRefs);
+ balance_queues(_discoveredWeakRefs);
+ balance_queues(_discoveredFinalRefs);
+ balance_queues(_discoveredPhantomRefs);
}
void
@@ -857,8 +929,17 @@
VoidClosure* complete_gc,
AbstractRefProcTaskExecutor* task_executor)
{
- bool mt = task_executor != NULL && _processing_is_mt;
- if (mt && ParallelRefProcBalancingEnabled) {
+ bool mt_processing = task_executor != NULL && _processing_is_mt;
+ // If discovery used MT and a dynamic number of GC threads, then
+ // the queues must be balanced for correctness if fewer than the
+ // maximum number of queues were used. The number of queue used
+ // during discovery may be different than the number to be used
+ // for processing so don't depend of _num_q < _max_num_q as part
+ // of the test.
+ bool must_balance = _discovery_is_mt;
+
+ if ((mt_processing && ParallelRefProcBalancingEnabled) ||
+ must_balance) {
balance_queues(refs_lists);
}
if (PrintReferenceGC && PrintGCDetails) {
@@ -875,7 +956,7 @@
// policy reasons. Keep alive the transitive closure of all
// such referents.
if (policy != NULL) {
- if (mt) {
+ if (mt_processing) {
RefProcPhase1Task phase1(*this, refs_lists, policy, true /*marks_oops_alive*/);
task_executor->execute(phase1);
} else {
@@ -891,7 +972,7 @@
// Phase 2:
// . Traverse the list and remove any refs whose referents are alive.
- if (mt) {
+ if (mt_processing) {
RefProcPhase2Task phase2(*this, refs_lists, !discovery_is_atomic() /*marks_oops_alive*/);
task_executor->execute(phase2);
} else {
@@ -902,7 +983,7 @@
// Phase 3:
// . Traverse the list and process referents as appropriate.
- if (mt) {
+ if (mt_processing) {
RefProcPhase3Task phase3(*this, refs_lists, clear_referent, true /*marks_oops_alive*/);
task_executor->execute(phase3);
} else {
@@ -915,7 +996,11 @@
void ReferenceProcessor::clean_up_discovered_references() {
// loop over the lists
- for (int i = 0; i < _num_q * subclasses_of_ref; i++) {
+ // Should this instead be
+ // for (int i = 0; i < subclasses_of_ref; i++_ {
+ // for (int j = 0; j < _num_q; j++) {
+ // int index = i * _max_num_q + j;
+ for (int i = 0; i < _max_num_q * subclasses_of_ref; i++) {
if (TraceReferenceGC && PrintGCDetails && ((i % _num_q) == 0)) {
gclog_or_tty->print_cr(
"\nScrubbing %s discovered list of Null referents",
@@ -976,7 +1061,7 @@
id = next_id();
}
}
- assert(0 <= id && id < _num_q, "Id is out-of-bounds (call Freud?)");
+ assert(0 <= id && id < _max_num_q, "Id is out-of-bounds (call Freud?)");
// Get the discovered queue to which we will add
DiscoveredList* list = NULL;
@@ -1001,6 +1086,10 @@
default:
ShouldNotReachHere();
}
+ if (TraceReferenceGC && PrintGCDetails) {
+ gclog_or_tty->print_cr("Thread %d gets list " INTPTR_FORMAT,
+ id, list);
+ }
return list;
}
@@ -1243,7 +1332,7 @@
{
TraceTime tt("Preclean SoftReferences", PrintGCDetails && PrintReferenceGC,
false, gclog_or_tty);
- for (int i = 0; i < _num_q; i++) {
+ for (int i = 0; i < _max_num_q; i++) {
if (yield->should_return()) {
return;
}
@@ -1340,15 +1429,16 @@
NOT_PRODUCT(
if (PrintGCDetails && PrintReferenceGC) {
- gclog_or_tty->print(" Dropped %d Refs out of %d "
- "Refs in discovered list ", iter.removed(), iter.processed());
+ gclog_or_tty->print_cr(" Dropped %d Refs out of %d "
+ "Refs in discovered list " INTPTR_FORMAT,
+ iter.removed(), iter.processed(), (address)refs_list.head());
}
)
}
const char* ReferenceProcessor::list_name(int i) {
- assert(i >= 0 && i <= _num_q * subclasses_of_ref, "Out of bounds index");
- int j = i / _num_q;
+ assert(i >= 0 && i <= _max_num_q * subclasses_of_ref, "Out of bounds index");
+ int j = i / _max_num_q;
switch (j) {
case 0: return "SoftRef";
case 1: return "WeakRef";
@@ -1372,7 +1462,7 @@
#ifndef PRODUCT
void ReferenceProcessor::clear_discovered_references() {
guarantee(!_discovering_refs, "Discovering refs?");
- for (int i = 0; i < _num_q * subclasses_of_ref; i++) {
+ for (int i = 0; i < _max_num_q * subclasses_of_ref; i++) {
oop obj = _discoveredSoftRefs[i].head();
while (obj != sentinel_ref()) {
oop next = java_lang_ref_Reference::discovered(obj);
--- a/hotspot/src/share/vm/memory/referenceProcessor.hpp Fri Oct 15 09:38:20 2010 +0200
+++ b/hotspot/src/share/vm/memory/referenceProcessor.hpp Fri Oct 15 02:59:48 2010 -0700
@@ -85,8 +85,10 @@
// The discovered ref lists themselves
- // The MT'ness degree of the queues below
+ // The active MT'ness degree of the queues below
int _num_q;
+ // The maximum MT'ness degree of the queues below
+ int _max_num_q;
// Arrays of lists of oops, one per thread
DiscoveredList* _discoveredSoftRefs;
DiscoveredList* _discoveredWeakRefs;
@@ -95,6 +97,7 @@
public:
int num_q() { return _num_q; }
+ void set_mt_degree(int v) { _num_q = v; }
DiscoveredList* discovered_soft_refs() { return _discoveredSoftRefs; }
static oop sentinel_ref() { return _sentinelRef; }
static oop* adr_sentinel_ref() { return &_sentinelRef; }
@@ -244,6 +247,7 @@
_bs(NULL),
_is_alive_non_header(NULL),
_num_q(0),
+ _max_num_q(0),
_processing_is_mt(false),
_next_id(0)
{}
@@ -312,6 +316,9 @@
void weak_oops_do(OopClosure* f); // weak roots
static void oops_do(OopClosure* f); // strong root(s)
+ // Balance each of the discovered lists.
+ void balance_all_queues();
+
// Discover a Reference object, using appropriate discovery criteria
bool discover_reference(oop obj, ReferenceType rt);
--- a/hotspot/src/share/vm/memory/sharedHeap.cpp Fri Oct 15 09:38:20 2010 +0200
+++ b/hotspot/src/share/vm/memory/sharedHeap.cpp Fri Oct 15 02:59:48 2010 -0700
@@ -1,5 +1,5 @@
/*
- * Copyright (c) 2000, 2009, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2000, 2010, Oracle and/or its affiliates. All rights reserved.
* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
*
* This code is free software; you can redistribute it and/or modify it
@@ -50,7 +50,8 @@
_perm_gen(NULL), _rem_set(NULL),
_strong_roots_parity(0),
_process_strong_tasks(new SubTasksDone(SH_PS_NumElements)),
- _workers(NULL), _n_par_threads(0)
+ _n_par_threads(0),
+ _workers(NULL)
{
if (_process_strong_tasks == NULL || !_process_strong_tasks->valid()) {
vm_exit_during_initialization("Failed necessary allocation.");
@@ -60,11 +61,13 @@
(UseConcMarkSweepGC && CMSParallelRemarkEnabled) ||
UseG1GC) &&
ParallelGCThreads > 0) {
- _workers = new WorkGang("Parallel GC Threads", ParallelGCThreads,
+ _workers = new FlexibleWorkGang("Parallel GC Threads", ParallelGCThreads,
/* are_GC_task_threads */true,
/* are_ConcurrentGC_threads */false);
if (_workers == NULL) {
vm_exit_during_initialization("Failed necessary allocation.");
+ } else {
+ _workers->initialize_workers();
}
}
}
@@ -77,8 +80,9 @@
}
void SharedHeap::set_par_threads(int t) {
+ assert(t == 0 || !UseSerialGC, "Cannot have parallel threads");
_n_par_threads = t;
- _process_strong_tasks->set_par_threads(t);
+ _process_strong_tasks->set_n_threads(t);
}
class AssertIsPermClosure: public OopClosure {
--- a/hotspot/src/share/vm/memory/sharedHeap.hpp Fri Oct 15 09:38:20 2010 +0200
+++ b/hotspot/src/share/vm/memory/sharedHeap.hpp Fri Oct 15 02:59:48 2010 -0700
@@ -1,5 +1,5 @@
/*
- * Copyright (c) 2000, 2009, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2000, 2010, Oracle and/or its affiliates. All rights reserved.
* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
*
* This code is free software; you can redistribute it and/or modify it
@@ -38,6 +38,7 @@
class ObjectClosure;
class SubTasksDone;
class WorkGang;
+class FlexibleWorkGang;
class CollectorPolicy;
class KlassHandle;
@@ -74,7 +75,7 @@
int _strong_roots_parity;
// If we're doing parallel GC, use this gang of threads.
- WorkGang* _workers;
+ FlexibleWorkGang* _workers;
// Number of parallel threads currently working on GC tasks.
// O indicates use sequential code; 1 means use parallel code even with
@@ -189,7 +190,7 @@
SO_CodeCache = 0x10
};
- WorkGang* workers() const { return _workers; }
+ FlexibleWorkGang* workers() const { return _workers; }
// Sets the number of parallel threads that will be doing tasks
// (such as process strong roots) subsequently.
--- a/hotspot/src/share/vm/runtime/globals.hpp Fri Oct 15 09:38:20 2010 +0200
+++ b/hotspot/src/share/vm/runtime/globals.hpp Fri Oct 15 02:59:48 2010 -0700
@@ -273,6 +273,10 @@
// UnlockExperimentalVMOptions flag, which allows the control and
// modification of the experimental flags.
//
+// Nota bene: neither diagnostic nor experimental options should be used casually,
+// and they are not supported on production loads, except under explicit
+// direction from support engineers.
+//
// manageable flags are writeable external product flags.
// They are dynamically writeable through the JDK management interface
// (com.sun.management.HotSpotDiagnosticMXBean API) and also through JConsole.
@@ -634,6 +638,9 @@
develop(bool, ZapJNIHandleArea, trueInDebug, \
"Zap freed JNI handle space with 0xFEFEFEFE") \
\
+ notproduct(bool, ZapStackSegments, trueInDebug, \
+ "Zap allocated/freed Stack segments with 0xFADFADED") \
+ \
develop(bool, ZapUnusedHeapArea, trueInDebug, \
"Zap unused heap space with 0xBAADBABE") \
\
@@ -1799,17 +1806,17 @@
develop(uintx, PromotionFailureALotInterval, 5, \
"Total collections between promotion failures alot") \
\
- develop(intx, WorkStealingSleepMillis, 1, \
+ experimental(intx, WorkStealingSleepMillis, 1, \
"Sleep time when sleep is used for yields") \
\
- develop(uintx, WorkStealingYieldsBeforeSleep, 1000, \
+ experimental(uintx, WorkStealingYieldsBeforeSleep, 1000, \
"Number of yields before a sleep is done during workstealing") \
\
- develop(uintx, WorkStealingHardSpins, 4096, \
+ experimental(uintx, WorkStealingHardSpins, 4096, \
"Number of iterations in a spin loop between checks on " \
"time out of hard spin") \
\
- develop(uintx, WorkStealingSpinToYieldRatio, 10, \
+ experimental(uintx, WorkStealingSpinToYieldRatio, 10, \
"Ratio of hard spins to calls to yield") \
\
product(uintx, PreserveMarkStackSize, 1024, \
--- a/hotspot/src/share/vm/runtime/thread.cpp Fri Oct 15 09:38:20 2010 +0200
+++ b/hotspot/src/share/vm/runtime/thread.cpp Fri Oct 15 02:59:48 2010 -0700
@@ -1645,7 +1645,29 @@
satb_mark_queue().flush();
dirty_card_queue().flush();
}
-#endif
+
+void JavaThread::initialize_queues() {
+ assert(!SafepointSynchronize::is_at_safepoint(),
+ "we should not be at a safepoint");
+
+ ObjPtrQueue& satb_queue = satb_mark_queue();
+ SATBMarkQueueSet& satb_queue_set = satb_mark_queue_set();
+ // The SATB queue should have been constructed with its active
+ // field set to false.
+ assert(!satb_queue.is_active(), "SATB queue should not be active");
+ assert(satb_queue.is_empty(), "SATB queue should be empty");
+ // If we are creating the thread during a marking cycle, we should
+ // set the active field of the SATB queue to true.
+ if (satb_queue_set.is_active()) {
+ satb_queue.set_active(true);
+ }
+
+ DirtyCardQueue& dirty_queue = dirty_card_queue();
+ // The dirty card queue should have been constructed with its
+ // active field set to true.
+ assert(dirty_queue.is_active(), "dirty card queue should be active");
+}
+#endif // !SERIALGC
void JavaThread::cleanup_failed_attach_current_thread() {
if (get_thread_profiler() != NULL) {
@@ -3627,6 +3649,10 @@
void Threads::add(JavaThread* p, bool force_daemon) {
// The threads lock must be owned at this point
assert_locked_or_safepoint(Threads_lock);
+
+ // See the comment for this method in thread.hpp for its purpose and
+ // why it is called here.
+ p->initialize_queues();
p->set_next(_thread_list);
_thread_list = p;
_number_of_threads++;
--- a/hotspot/src/share/vm/runtime/thread.hpp Fri Oct 15 09:38:20 2010 +0200
+++ b/hotspot/src/share/vm/runtime/thread.hpp Fri Oct 15 02:59:48 2010 -0700
@@ -1490,6 +1490,29 @@
}
#endif // !SERIALGC
+ // This method initializes the SATB and dirty card queues before a
+ // JavaThread is added to the Java thread list. Right now, we don't
+ // have to do anything to the dirty card queue (it should have been
+ // activated when the thread was created), but we have to activate
+ // the SATB queue if the thread is created while a marking cycle is
+ // in progress. The activation / de-activation of the SATB queues at
+ // the beginning / end of a marking cycle is done during safepoints
+ // so we have to make sure this method is called outside one to be
+ // able to safely read the active field of the SATB queue set. Right
+ // now, it is called just before the thread is added to the Java
+ // thread list in the Threads::add() method. That method is holding
+ // the Threads_lock which ensures we are outside a safepoint. We
+ // cannot do the obvious and set the active field of the SATB queue
+ // when the thread is created given that, in some cases, safepoints
+ // might happen between the JavaThread constructor being called and the
+ // thread being added to the Java thread list (an example of this is
+ // when the structure for the DestroyJavaVM thread is created).
+#ifndef SERIALGC
+ void initialize_queues();
+#else // !SERIALGC
+ void initialize_queues() { }
+#endif // !SERIALGC
+
// Machine dependent stuff
#include "incls/_thread_pd.hpp.incl"
--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/hotspot/src/share/vm/utilities/stack.hpp Fri Oct 15 02:59:48 2010 -0700
@@ -0,0 +1,204 @@
+/*
+ * Copyright 2009 Sun Microsystems, Inc. All Rights Reserved.
+ * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
+ *
+ * This code is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 only, as
+ * published by the Free Software Foundation.
+ *
+ * This code is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
+ * version 2 for more details (a copy is included in the LICENSE file that
+ * accompanied this code).
+ *
+ * You should have received a copy of the GNU General Public License version
+ * 2 along with this work; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
+ * CA 95054 USA or visit www.sun.com if you need additional information or
+ * have any questions.
+ *
+ */
+
+// Class Stack (below) grows and shrinks by linking together "segments" which
+// are allocated on demand. Segments are arrays of the element type (E) plus an
+// extra pointer-sized field to store the segment link. Recently emptied
+// segments are kept in a cache and reused.
+//
+// Notes/caveats:
+//
+// The size of an element must either evenly divide the size of a pointer or be
+// a multiple of the size of a pointer.
+//
+// Destructors are not called for elements popped off the stack, so element
+// types which rely on destructors for things like reference counting will not
+// work properly.
+//
+// Class Stack allocates segments from the C heap. However, two protected
+// virtual methods are used to alloc/free memory which subclasses can override:
+//
+// virtual void* alloc(size_t bytes);
+// virtual void free(void* addr, size_t bytes);
+//
+// The alloc() method must return storage aligned for any use. The
+// implementation in class Stack assumes that alloc() will terminate the process
+// if the allocation fails.
+
+template <class E> class StackIterator;
+
+// StackBase holds common data/methods that don't depend on the element type,
+// factored out to reduce template code duplication.
+class StackBase
+{
+public:
+ size_t segment_size() const { return _seg_size; } // Elements per segment.
+ size_t max_size() const { return _max_size; } // Max elements allowed.
+ size_t max_cache_size() const { return _max_cache_size; } // Max segments
+ // allowed in cache.
+
+ size_t cache_size() const { return _cache_size; } // Segments in the cache.
+
+protected:
+ // The ctor arguments correspond to the like-named functions above.
+ // segment_size: number of items per segment
+ // max_cache_size: maxmium number of *segments* to cache
+ // max_size: maximum number of items allowed, rounded to a multiple of
+ // the segment size (0 == unlimited)
+ inline StackBase(size_t segment_size, size_t max_cache_size, size_t max_size);
+
+ // Round max_size to a multiple of the segment size. Treat 0 as unlimited.
+ static inline size_t adjust_max_size(size_t max_size, size_t seg_size);
+
+protected:
+ const size_t _seg_size; // Number of items per segment.
+ const size_t _max_size; // Maximum number of items allowed in the stack.
+ const size_t _max_cache_size; // Maximum number of segments to cache.
+ size_t _cur_seg_size; // Number of items in the current segment.
+ size_t _full_seg_size; // Number of items in already-filled segments.
+ size_t _cache_size; // Number of segments in the cache.
+};
+
+#ifdef __GNUC__
+#define inline
+#endif // __GNUC__
+
+template <class E>
+class Stack: public StackBase
+{
+public:
+ friend class StackIterator<E>;
+
+ // segment_size: number of items per segment
+ // max_cache_size: maxmium number of *segments* to cache
+ // max_size: maximum number of items allowed, rounded to a multiple of
+ // the segment size (0 == unlimited)
+ inline Stack(size_t segment_size = default_segment_size(),
+ size_t max_cache_size = 4, size_t max_size = 0);
+ inline ~Stack() { clear(true); }
+
+ inline bool is_empty() const { return _cur_seg == NULL; }
+ inline bool is_full() const { return _full_seg_size >= max_size(); }
+
+ // Performance sensitive code should use is_empty() instead of size() == 0 and
+ // is_full() instead of size() == max_size(). Using a conditional here allows
+ // just one var to be updated when pushing/popping elements instead of two;
+ // _full_seg_size is updated only when pushing/popping segments.
+ inline size_t size() const {
+ return is_empty() ? 0 : _full_seg_size + _cur_seg_size;
+ }
+
+ inline void push(E elem);
+ inline E pop();
+
+ // Clear everything from the stack, releasing the associated memory. If
+ // clear_cache is true, also release any cached segments.
+ void clear(bool clear_cache = false);
+
+ static inline size_t default_segment_size();
+
+protected:
+ // Each segment includes space for _seg_size elements followed by a link
+ // (pointer) to the previous segment; the space is allocated as a single block
+ // of size segment_bytes(). _seg_size is rounded up if necessary so the link
+ // is properly aligned. The C struct for the layout would be:
+ //
+ // struct segment {
+ // E elements[_seg_size];
+ // E* link;
+ // };
+
+ // Round up seg_size to keep the link field aligned.
+ static inline size_t adjust_segment_size(size_t seg_size);
+
+ // Methods for allocation size and getting/setting the link.
+ inline size_t link_offset() const; // Byte offset of link field.
+ inline size_t segment_bytes() const; // Segment size in bytes.
+ inline E** link_addr(E* seg) const; // Address of the link field.
+ inline E* get_link(E* seg) const; // Extract the link from seg.
+ inline E* set_link(E* new_seg, E* old_seg); // new_seg.link = old_seg.
+
+ virtual E* alloc(size_t bytes);
+ virtual void free(E* addr, size_t bytes);
+
+ void push_segment();
+ void pop_segment();
+
+ void free_segments(E* seg); // Free all segments in the list.
+ inline void reset(bool reset_cache); // Reset all data fields.
+
+ DEBUG_ONLY(void verify(bool at_empty_transition) const;)
+ DEBUG_ONLY(void zap_segment(E* seg, bool zap_link_field) const;)
+
+private:
+ E* _cur_seg; // Current segment.
+ E* _cache; // Segment cache to avoid ping-ponging.
+};
+
+template <class E> class ResourceStack: public Stack<E>, public ResourceObj
+{
+public:
+ // If this class becomes widely used, it may make sense to save the Thread
+ // and use it when allocating segments.
+ ResourceStack(size_t segment_size = Stack<E>::default_segment_size()):
+ Stack<E>(segment_size, max_uintx)
+ { }
+
+ // Set the segment pointers to NULL so the parent dtor does not free them;
+ // that must be done by the ResourceMark code.
+ ~ResourceStack() { Stack<E>::reset(true); }
+
+protected:
+ virtual E* alloc(size_t bytes);
+ virtual void free(E* addr, size_t bytes);
+
+private:
+ void clear(bool clear_cache = false);
+};
+
+template <class E>
+class StackIterator: public StackObj
+{
+public:
+ StackIterator(Stack<E>& stack): _stack(stack) { sync(); }
+
+ Stack<E>& stack() const { return _stack; }
+
+ bool is_empty() const { return _cur_seg == NULL; }
+
+ E next() { return *next_addr(); }
+ E* next_addr();
+
+ void sync(); // Sync the iterator's state to the stack's current state.
+
+private:
+ Stack<E>& _stack;
+ size_t _cur_seg_size;
+ E* _cur_seg;
+ size_t _full_seg_size;
+};
+
+#ifdef __GNUC__
+#undef inline
+#endif // __GNUC__
--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/hotspot/src/share/vm/utilities/stack.inline.hpp Fri Oct 15 02:59:48 2010 -0700
@@ -0,0 +1,273 @@
+/*
+ * Copyright 2009 Sun Microsystems, Inc. All Rights Reserved.
+ * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
+ *
+ * This code is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 only, as
+ * published by the Free Software Foundation.
+ *
+ * This code is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
+ * version 2 for more details (a copy is included in the LICENSE file that
+ * accompanied this code).
+ *
+ * You should have received a copy of the GNU General Public License version
+ * 2 along with this work; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
+ * CA 95054 USA or visit www.sun.com if you need additional information or
+ * have any questions.
+ *
+ */
+
+StackBase::StackBase(size_t segment_size, size_t max_cache_size,
+ size_t max_size):
+ _seg_size(segment_size),
+ _max_cache_size(max_cache_size),
+ _max_size(adjust_max_size(max_size, segment_size))
+{
+ assert(_max_size % _seg_size == 0, "not a multiple");
+}
+
+size_t StackBase::adjust_max_size(size_t max_size, size_t seg_size)
+{
+ assert(seg_size > 0, "cannot be 0");
+ assert(max_size >= seg_size || max_size == 0, "max_size too small");
+ const size_t limit = max_uintx - (seg_size - 1);
+ if (max_size == 0 || max_size > limit) {
+ max_size = limit;
+ }
+ return (max_size + seg_size - 1) / seg_size * seg_size;
+}
+
+template <class E>
+Stack<E>::Stack(size_t segment_size, size_t max_cache_size, size_t max_size):
+ StackBase(adjust_segment_size(segment_size), max_cache_size, max_size)
+{
+ reset(true);
+}
+
+template <class E>
+void Stack<E>::push(E item)
+{
+ assert(!is_full(), "pushing onto a full stack");
+ if (_cur_seg_size == _seg_size) {
+ push_segment();
+ }
+ _cur_seg[_cur_seg_size] = item;
+ ++_cur_seg_size;
+}
+
+template <class E>
+E Stack<E>::pop()
+{
+ assert(!is_empty(), "popping from an empty stack");
+ if (_cur_seg_size == 1) {
+ E tmp = _cur_seg[--_cur_seg_size];
+ pop_segment();
+ return tmp;
+ }
+ return _cur_seg[--_cur_seg_size];
+}
+
+template <class E>
+void Stack<E>::clear(bool clear_cache)
+{
+ free_segments(_cur_seg);
+ if (clear_cache) free_segments(_cache);
+ reset(clear_cache);
+}
+
+template <class E>
+size_t Stack<E>::default_segment_size()
+{
+ // Number of elements that fit in 4K bytes minus the size of two pointers
+ // (link field and malloc header).
+ return (4096 - 2 * sizeof(E*)) / sizeof(E);
+}
+
+template <class E>
+size_t Stack<E>::adjust_segment_size(size_t seg_size)
+{
+ const size_t elem_sz = sizeof(E);
+ const size_t ptr_sz = sizeof(E*);
+ assert(elem_sz % ptr_sz == 0 || ptr_sz % elem_sz == 0, "bad element size");
+ if (elem_sz < ptr_sz) {
+ return align_size_up(seg_size * elem_sz, ptr_sz) / elem_sz;
+ }
+ return seg_size;
+}
+
+template <class E>
+size_t Stack<E>::link_offset() const
+{
+ return align_size_up(_seg_size * sizeof(E), sizeof(E*));
+}
+
+template <class E>
+size_t Stack<E>::segment_bytes() const
+{
+ return link_offset() + sizeof(E*);
+}
+
+template <class E>
+E** Stack<E>::link_addr(E* seg) const
+{
+ return (E**) ((char*)seg + link_offset());
+}
+
+template <class E>
+E* Stack<E>::get_link(E* seg) const
+{
+ return *link_addr(seg);
+}
+
+template <class E>
+E* Stack<E>::set_link(E* new_seg, E* old_seg)
+{
+ *link_addr(new_seg) = old_seg;
+ return new_seg;
+}
+
+template <class E>
+E* Stack<E>::alloc(size_t bytes)
+{
+ return (E*) NEW_C_HEAP_ARRAY(char, bytes);
+}
+
+template <class E>
+void Stack<E>::free(E* addr, size_t bytes)
+{
+ FREE_C_HEAP_ARRAY(char, (char*) addr);
+}
+
+template <class E>
+void Stack<E>::push_segment()
+{
+ assert(_cur_seg_size == _seg_size, "current segment is not full");
+ E* next;
+ if (_cache_size > 0) {
+ // Use a cached segment.
+ next = _cache;
+ _cache = get_link(_cache);
+ --_cache_size;
+ } else {
+ next = alloc(segment_bytes());
+ DEBUG_ONLY(zap_segment(next, true);)
+ }
+ const bool at_empty_transition = is_empty();
+ _cur_seg = set_link(next, _cur_seg);
+ _cur_seg_size = 0;
+ _full_seg_size += at_empty_transition ? 0 : _seg_size;
+ DEBUG_ONLY(verify(at_empty_transition);)
+}
+
+template <class E>
+void Stack<E>::pop_segment()
+{
+ assert(_cur_seg_size == 0, "current segment is not empty");
+ E* const prev = get_link(_cur_seg);
+ if (_cache_size < _max_cache_size) {
+ // Add the current segment to the cache.
+ DEBUG_ONLY(zap_segment(_cur_seg, false);)
+ _cache = set_link(_cur_seg, _cache);
+ ++_cache_size;
+ } else {
+ DEBUG_ONLY(zap_segment(_cur_seg, true);)
+ free(_cur_seg, segment_bytes());
+ }
+ const bool at_empty_transition = prev == NULL;
+ _cur_seg = prev;
+ _cur_seg_size = _seg_size;
+ _full_seg_size -= at_empty_transition ? 0 : _seg_size;
+ DEBUG_ONLY(verify(at_empty_transition);)
+}
+
+template <class E>
+void Stack<E>::free_segments(E* seg)
+{
+ const size_t bytes = segment_bytes();
+ while (seg != NULL) {
+ E* const prev = get_link(seg);
+ free(seg, bytes);
+ seg = prev;
+ }
+}
+
+template <class E>
+void Stack<E>::reset(bool reset_cache)
+{
+ _cur_seg_size = _seg_size; // So push() will alloc a new segment.
+ _full_seg_size = 0;
+ _cur_seg = NULL;
+ if (reset_cache) {
+ _cache_size = 0;
+ _cache = NULL;
+ }
+}
+
+#ifdef ASSERT
+template <class E>
+void Stack<E>::verify(bool at_empty_transition) const
+{
+ assert(size() <= max_size(), "stack exceeded bounds");
+ assert(cache_size() <= max_cache_size(), "cache exceeded bounds");
+ assert(_cur_seg_size <= segment_size(), "segment index exceeded bounds");
+
+ assert(_full_seg_size % _seg_size == 0, "not a multiple");
+ assert(at_empty_transition || is_empty() == (size() == 0), "mismatch");
+ assert((_cache == NULL) == (cache_size() == 0), "mismatch");
+
+ if (is_empty()) {
+ assert(_cur_seg_size == segment_size(), "sanity");
+ }
+}
+
+template <class E>
+void Stack<E>::zap_segment(E* seg, bool zap_link_field) const
+{
+ if (!ZapStackSegments) return;
+ const size_t zap_bytes = segment_bytes() - (zap_link_field ? 0 : sizeof(E*));
+ uint32_t* cur = (uint32_t*)seg;
+ const uint32_t* end = cur + zap_bytes / sizeof(uint32_t);
+ while (cur < end) {
+ *cur++ = 0xfadfaded;
+ }
+}
+#endif
+
+template <class E>
+E* ResourceStack<E>::alloc(size_t bytes)
+{
+ return (E*) resource_allocate_bytes(bytes);
+}
+
+template <class E>
+void ResourceStack<E>::free(E* addr, size_t bytes)
+{
+ resource_free_bytes((char*) addr, bytes);
+}
+
+template <class E>
+void StackIterator<E>::sync()
+{
+ _full_seg_size = _stack._full_seg_size;
+ _cur_seg_size = _stack._cur_seg_size;
+ _cur_seg = _stack._cur_seg;
+}
+
+template <class E>
+E* StackIterator<E>::next_addr()
+{
+ assert(!is_empty(), "no items left");
+ if (_cur_seg_size == 1) {
+ E* addr = _cur_seg;
+ _cur_seg = _stack.get_link(_cur_seg);
+ _cur_seg_size = _stack.segment_size();
+ _full_seg_size -= _stack.segment_size();
+ return addr;
+ }
+ return _cur_seg + --_cur_seg_size;
+}
--- a/hotspot/src/share/vm/utilities/taskqueue.cpp Fri Oct 15 09:38:20 2010 +0200
+++ b/hotspot/src/share/vm/utilities/taskqueue.cpp Fri Oct 15 02:59:48 2010 -0700
@@ -144,6 +144,7 @@
bool
ParallelTaskTerminator::offer_termination(TerminatorTerminator* terminator) {
+ assert(_n_threads > 0, "Initialization is incorrect");
assert(_offered_termination < _n_threads, "Invariant");
Atomic::inc(&_offered_termination);
@@ -255,3 +256,9 @@
_index < objArrayOop(_obj)->length();
}
#endif // ASSERT
+
+void ParallelTaskTerminator::reset_for_reuse(int n_threads) {
+ reset_for_reuse();
+ _n_threads = n_threads;
+}
+
--- a/hotspot/src/share/vm/utilities/taskqueue.hpp Fri Oct 15 09:38:20 2010 +0200
+++ b/hotspot/src/share/vm/utilities/taskqueue.hpp Fri Oct 15 02:59:48 2010 -0700
@@ -305,6 +305,12 @@
return false;
}
+// pop_local_slow() is done by the owning thread and is trying to
+// get the last task in the queue. It will compete with pop_global()
+// that will be used by other threads. The tag age is incremented
+// whenever the queue goes empty which it will do here if this thread
+// gets the last task or in pop_global() if the queue wraps (top == 0
+// and pop_global() succeeds, see pop_global()).
template<class E, unsigned int N>
bool GenericTaskQueue<E, N>::pop_local_slow(uint localBot, Age oldAge) {
// This queue was observed to contain exactly one element; either this
@@ -366,75 +372,47 @@
// OverflowTaskQueue is a TaskQueue that also includes an overflow stack for
// elements that do not fit in the TaskQueue.
//
-// Three methods from super classes are overridden:
+// This class hides two methods from super classes:
//
-// initialize() - initialize the super classes and create the overflow stack
// push() - push onto the task queue or, if that fails, onto the overflow stack
// is_empty() - return true if both the TaskQueue and overflow stack are empty
//
-// Note that size() is not overridden--it returns the number of elements in the
+// Note that size() is not hidden--it returns the number of elements in the
// TaskQueue, and does not include the size of the overflow stack. This
// simplifies replacement of GenericTaskQueues with OverflowTaskQueues.
template<class E, unsigned int N = TASKQUEUE_SIZE>
class OverflowTaskQueue: public GenericTaskQueue<E, N>
{
public:
- typedef GrowableArray<E> overflow_t;
+ typedef Stack<E> overflow_t;
typedef GenericTaskQueue<E, N> taskqueue_t;
TASKQUEUE_STATS_ONLY(using taskqueue_t::stats;)
- OverflowTaskQueue();
- ~OverflowTaskQueue();
- void initialize();
-
- inline overflow_t* overflow_stack() const { return _overflow_stack; }
-
// Push task t onto the queue or onto the overflow stack. Return true.
inline bool push(E t);
// Attempt to pop from the overflow stack; return true if anything was popped.
inline bool pop_overflow(E& t);
+ inline overflow_t* overflow_stack() { return &_overflow_stack; }
+
inline bool taskqueue_empty() const { return taskqueue_t::is_empty(); }
- inline bool overflow_empty() const { return overflow_stack()->is_empty(); }
+ inline bool overflow_empty() const { return _overflow_stack.is_empty(); }
inline bool is_empty() const {
return taskqueue_empty() && overflow_empty();
}
private:
- overflow_t* _overflow_stack;
+ overflow_t _overflow_stack;
};
template <class E, unsigned int N>
-OverflowTaskQueue<E, N>::OverflowTaskQueue()
-{
- _overflow_stack = NULL;
-}
-
-template <class E, unsigned int N>
-OverflowTaskQueue<E, N>::~OverflowTaskQueue()
-{
- if (_overflow_stack != NULL) {
- delete _overflow_stack;
- _overflow_stack = NULL;
- }
-}
-
-template <class E, unsigned int N>
-void OverflowTaskQueue<E, N>::initialize()
-{
- taskqueue_t::initialize();
- assert(_overflow_stack == NULL, "memory leak");
- _overflow_stack = new (ResourceObj::C_HEAP) GrowableArray<E>(10, true);
-}
-
-template <class E, unsigned int N>
bool OverflowTaskQueue<E, N>::push(E t)
{
if (!taskqueue_t::push(t)) {
overflow_stack()->push(t);
- TASKQUEUE_STATS_ONLY(stats.record_overflow(overflow_stack()->length()));
+ TASKQUEUE_STATS_ONLY(stats.record_overflow(overflow_stack()->size()));
}
return true;
}
@@ -637,6 +615,9 @@
// in an MT-safe manner, once the previous round of use of
// the terminator is finished.
void reset_for_reuse();
+ // Same as above but the number of parallel threads is set to the
+ // given number.
+ void reset_for_reuse(int n_threads);
#ifdef TRACESPINNING
static uint total_yields() { return _total_yields; }
@@ -782,3 +763,4 @@
typedef OverflowTaskQueue<size_t> RegionTaskQueue;
typedef GenericTaskQueueSet<RegionTaskQueue> RegionTaskQueueSet;
+
--- a/hotspot/src/share/vm/utilities/workgroup.cpp Fri Oct 15 09:38:20 2010 +0200
+++ b/hotspot/src/share/vm/utilities/workgroup.cpp Fri Oct 15 02:59:48 2010 -0700
@@ -1,5 +1,5 @@
/*
- * Copyright (c) 2001, 2007, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2001, 2010, Oracle and/or its affiliates. All rights reserved.
* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
*
* This code is free software; you can redistribute it and/or modify it
@@ -53,28 +53,52 @@
int workers,
bool are_GC_task_threads,
bool are_ConcurrentGC_threads) :
- AbstractWorkGang(name, are_GC_task_threads, are_ConcurrentGC_threads)
-{
+ AbstractWorkGang(name, are_GC_task_threads, are_ConcurrentGC_threads) {
// Save arguments.
_total_workers = workers;
+}
+
+GangWorker* WorkGang::allocate_worker(int which) {
+ GangWorker* new_worker = new GangWorker(this, which);
+ return new_worker;
+}
+
+// The current implementation will exit if the allocation
+// of any worker fails. Still, return a boolean so that
+// a future implementation can possibly do a partial
+// initialization of the workers and report such to the
+// caller.
+bool WorkGang::initialize_workers() {
if (TraceWorkGang) {
- tty->print_cr("Constructing work gang %s with %d threads", name, workers);
+ tty->print_cr("Constructing work gang %s with %d threads",
+ name(),
+ total_workers());
}
- _gang_workers = NEW_C_HEAP_ARRAY(GangWorker*, workers);
+ _gang_workers = NEW_C_HEAP_ARRAY(GangWorker*, total_workers());
if (gang_workers() == NULL) {
vm_exit_out_of_memory(0, "Cannot create GangWorker array.");
+ return false;
+ }
+ os::ThreadType worker_type;
+ if (are_ConcurrentGC_threads()) {
+ worker_type = os::cgc_thread;
+ } else {
+ worker_type = os::pgc_thread;
}
for (int worker = 0; worker < total_workers(); worker += 1) {
- GangWorker* new_worker = new GangWorker(this, worker);
+ GangWorker* new_worker = allocate_worker(worker);
assert(new_worker != NULL, "Failed to allocate GangWorker");
_gang_workers[worker] = new_worker;
- if (new_worker == NULL || !os::create_thread(new_worker, os::pgc_thread))
+ if (new_worker == NULL || !os::create_thread(new_worker, worker_type)) {
vm_exit_out_of_memory(0, "Cannot create worker GC thread. Out of system resources.");
+ return false;
+ }
if (!DisableStartThread) {
os::start_thread(new_worker);
}
}
+ return true;
}
AbstractWorkGang::~AbstractWorkGang() {
@@ -383,7 +407,7 @@
return _tasks != NULL;
}
-void SubTasksDone::set_par_threads(int t) {
+void SubTasksDone::set_n_threads(int t) {
#ifdef ASSERT
assert(_claimed == 0 || _threads_completed == _n_threads,
"should not be called while tasks are being processed!");
--- a/hotspot/src/share/vm/utilities/workgroup.hpp Fri Oct 15 09:38:20 2010 +0200
+++ b/hotspot/src/share/vm/utilities/workgroup.hpp Fri Oct 15 02:59:48 2010 -0700
@@ -1,5 +1,5 @@
/*
- * Copyright (c) 2002, 2009, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2002, 2010, Oracle and/or its affiliates. All rights reserved.
* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
*
* This code is free software; you can redistribute it and/or modify it
@@ -29,6 +29,7 @@
class YieldingFlexibleGangWorker;
class YieldingFlexibleGangTask;
class WorkData;
+class AbstractWorkGang;
// An abstract task to be worked on by a gang.
// You subclass this to supply your own work() method
@@ -38,6 +39,13 @@
// The argument tells you which member of the gang you are.
virtual void work(int i) = 0;
+ // This method configures the task for proper termination.
+ // Some tasks do not have any requirements on termination
+ // and may inherit this method that does nothing. Some
+ // tasks do some coordination on termination and override
+ // this method to implement that coordination.
+ virtual void set_for_termination(int active_workers) {};
+
// Debugging accessor for the name.
const char* name() const PRODUCT_RETURN_(return NULL;);
int counter() { return _counter; }
@@ -64,6 +72,18 @@
virtual ~AbstractGangTask() { }
};
+class AbstractGangTaskWOopQueues : public AbstractGangTask {
+ OopTaskQueueSet* _queues;
+ ParallelTaskTerminator _terminator;
+ public:
+ AbstractGangTaskWOopQueues(const char* name, OopTaskQueueSet* queues) :
+ AbstractGangTask(name), _queues(queues), _terminator(0, _queues) {}
+ ParallelTaskTerminator* terminator() { return &_terminator; }
+ virtual void set_for_termination(int active_workers) {
+ terminator()->reset_for_reuse(active_workers);
+ }
+ OopTaskQueueSet* queues() { return _queues; }
+};
// Class AbstractWorkGang:
// An abstract class representing a gang of workers.
@@ -114,6 +134,9 @@
int total_workers() const {
return _total_workers;
}
+ virtual int active_workers() const {
+ return _total_workers;
+ }
bool terminate() const {
return _terminate;
}
@@ -199,6 +222,13 @@
bool are_GC_task_threads, bool are_ConcurrentGC_threads);
// Run a task, returns when the task is done (or terminated).
virtual void run_task(AbstractGangTask* task);
+ void run_task(AbstractGangTask* task, uint no_of_parallel_workers);
+ // Allocate a worker and return a pointer to it.
+ virtual GangWorker* allocate_worker(int which);
+ // Initialize workers in the gang. Return true if initialization
+ // succeeded. The type of the worker can be overridden in a derived
+ // class with the appropriate implementation of allocate_worker().
+ bool initialize_workers();
};
// Class GangWorker:
@@ -226,6 +256,34 @@
AbstractWorkGang* gang() const { return _gang; }
};
+class FlexibleWorkGang: public WorkGang {
+ protected:
+ int _active_workers;
+ public:
+ // Constructor and destructor.
+ FlexibleWorkGang(const char* name, int workers,
+ bool are_GC_task_threads,
+ bool are_ConcurrentGC_threads) :
+ WorkGang(name, workers, are_GC_task_threads, are_ConcurrentGC_threads) {
+ _active_workers = ParallelGCThreads;
+ };
+ // Accessors for fields
+ virtual int active_workers() const { return _active_workers; }
+ void set_active_workers(int v) { _active_workers = v; }
+};
+
+// Work gangs in garbage collectors: 2009-06-10
+//
+// SharedHeap - work gang for stop-the-world parallel collection.
+// Used by
+// ParNewGeneration
+// CMSParRemarkTask
+// CMSRefProcTaskExecutor
+// G1CollectedHeap
+// G1ParFinalCountTask
+// ConcurrentMark
+// CMSCollector
+
// A class that acts as a synchronisation barrier. Workers enter
// the barrier and must wait until all other workers have entered
// before any of them may leave.
@@ -271,7 +329,7 @@
int _n_threads;
jint _threads_completed;
#ifdef ASSERT
- jint _claimed;
+ volatile jint _claimed;
#endif
// Set all tasks to unclaimed.
@@ -286,9 +344,10 @@
// True iff the object is in a valid state.
bool valid();
- // Set the number of parallel threads doing the tasks to "t". Can only
+ // Get/set the number of parallel threads doing the tasks to "t". Can only
// be called before tasks start or after they are complete.
- void set_par_threads(int t);
+ int n_threads() { return _n_threads; }
+ void set_n_threads(int t);
// Returns "false" if the task "t" is unclaimed, and ensures that task is
// claimed. The task "t" is required to be within the range of "this".
@@ -315,13 +374,17 @@
protected:
jint _n_tasks; // Total number of tasks available.
jint _n_claimed; // Number of tasks claimed.
+ // _n_threads is used to determine when a sub task is done.
+ // See comments on SubTasksDone::_n_threads
jint _n_threads; // Total number of parallel threads.
jint _n_completed; // Number of completed threads.
void clear();
public:
- SequentialSubTasksDone() { clear(); }
+ SequentialSubTasksDone() {
+ clear();
+ }
~SequentialSubTasksDone() {}
// True iff the object is in a valid state.
@@ -330,11 +393,12 @@
// number of tasks
jint n_tasks() const { return _n_tasks; }
- // Set the number of parallel threads doing the tasks to t.
+ // Get/set the number of parallel threads doing the tasks to t.
// Should be called before the task starts but it is safe
// to call this once a task is running provided that all
// threads agree on the number of threads.
- void set_par_threads(int t) { _n_threads = t; }
+ int n_threads() { return _n_threads; }
+ void set_n_threads(int t) { _n_threads = t; }
// Set the number of tasks to be claimed to t. As above,
// should be called before the tasks start but it is safe
--- a/hotspot/src/share/vm/utilities/yieldingWorkgroup.cpp Fri Oct 15 09:38:20 2010 +0200
+++ b/hotspot/src/share/vm/utilities/yieldingWorkgroup.cpp Fri Oct 15 02:59:48 2010 -0700
@@ -1,5 +1,5 @@
/*
- * Copyright (c) 2005, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2005, 2010 Oracle and/or its affiliates. All rights reserved.
* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
*
* This code is free software; you can redistribute it and/or modify it
@@ -32,29 +32,13 @@
YieldingFlexibleWorkGang::YieldingFlexibleWorkGang(
const char* name, int workers, bool are_GC_task_threads) :
- AbstractWorkGang(name, are_GC_task_threads, false) {
- // Save arguments.
- _total_workers = workers;
- assert(_total_workers > 0, "Must have more than 1 worker");
-
- _yielded_workers = 0;
+ FlexibleWorkGang(name, workers, are_GC_task_threads, false),
+ _yielded_workers(0) {}
- if (TraceWorkGang) {
- tty->print_cr("Constructing work gang %s with %d threads", name, workers);
- }
- _gang_workers = NEW_C_HEAP_ARRAY(GangWorker*, workers);
- assert(gang_workers() != NULL, "Failed to allocate gang workers");
- for (int worker = 0; worker < total_workers(); worker += 1) {
- YieldingFlexibleGangWorker* new_worker =
- new YieldingFlexibleGangWorker(this, worker);
- assert(new_worker != NULL, "Failed to allocate YieldingFlexibleGangWorker");
- _gang_workers[worker] = new_worker;
- if (new_worker == NULL || !os::create_thread(new_worker, os::pgc_thread))
- vm_exit_out_of_memory(0, "Cannot create worker GC thread. Out of system resources.");
- if (!DisableStartThread) {
- os::start_thread(new_worker);
- }
- }
+GangWorker* YieldingFlexibleWorkGang::allocate_worker(int which) {
+ YieldingFlexibleGangWorker* new_member =
+ new YieldingFlexibleGangWorker(this, which);
+ return (YieldingFlexibleGangWorker*) new_member;
}
// Run a task; returns when the task is done, or the workers yield,
@@ -142,6 +126,7 @@
_active_workers = total_workers();
}
new_task->set_actual_size(_active_workers);
+ new_task->set_for_termination(_active_workers);
assert(_started_workers == 0, "Tabula rasa non");
assert(_finished_workers == 0, "Tabula rasa non");
@@ -161,22 +146,22 @@
for (Status status = yielding_task()->status();
status != COMPLETED && status != YIELDED && status != ABORTED;
status = yielding_task()->status()) {
- assert(started_workers() <= active_workers(), "invariant");
- assert(finished_workers() <= active_workers(), "invariant");
- assert(yielded_workers() <= active_workers(), "invariant");
+ assert(started_workers() <= total_workers(), "invariant");
+ assert(finished_workers() <= total_workers(), "invariant");
+ assert(yielded_workers() <= total_workers(), "invariant");
monitor()->wait(Mutex::_no_safepoint_check_flag);
}
switch (yielding_task()->status()) {
case COMPLETED:
case ABORTED: {
- assert(finished_workers() == active_workers(), "Inconsistent status");
+ assert(finished_workers() == total_workers(), "Inconsistent status");
assert(yielded_workers() == 0, "Invariant");
reset(); // for next task; gang<->task binding released
break;
}
case YIELDED: {
assert(yielded_workers() > 0, "Invariant");
- assert(yielded_workers() + finished_workers() == active_workers(),
+ assert(yielded_workers() + finished_workers() == total_workers(),
"Inconsistent counts");
break;
}
@@ -208,7 +193,6 @@
void YieldingFlexibleWorkGang::reset() {
_started_workers = 0;
_finished_workers = 0;
- _active_workers = 0;
yielding_task()->set_gang(NULL);
_task = NULL; // unbind gang from task
}
@@ -216,7 +200,7 @@
void YieldingFlexibleWorkGang::yield() {
assert(task() != NULL, "Inconsistency; should have task binding");
MutexLockerEx ml(monitor(), Mutex::_no_safepoint_check_flag);
- assert(yielded_workers() < active_workers(), "Consistency check");
+ assert(yielded_workers() < total_workers(), "Consistency check");
if (yielding_task()->status() == ABORTING) {
// Do not yield; we need to abort as soon as possible
// XXX NOTE: This can cause a performance pathology in the
@@ -227,7 +211,7 @@
// us to return at each potential yield point.
return;
}
- if (++_yielded_workers + finished_workers() == active_workers()) {
+ if (++_yielded_workers + finished_workers() == total_workers()) {
yielding_task()->set_status(YIELDED);
monitor()->notify_all();
} else {
--- a/hotspot/src/share/vm/utilities/yieldingWorkgroup.hpp Fri Oct 15 09:38:20 2010 +0200
+++ b/hotspot/src/share/vm/utilities/yieldingWorkgroup.hpp Fri Oct 15 02:59:48 2010 -0700
@@ -1,5 +1,5 @@
/*
- * Copyright (c) 2005, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2005, 2010, Oracle and/or its affiliates. All rights reserved.
* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
*
* This code is free software; you can redistribute it and/or modify it
@@ -54,6 +54,25 @@
virtual void loop();
};
+class FlexibleGangTask: public AbstractGangTask {
+ int _actual_size; // size of gang obtained
+protected:
+ int _requested_size; // size of gang requested
+public:
+ FlexibleGangTask(const char* name): AbstractGangTask(name),
+ _requested_size(0) {}
+
+ // The abstract work method.
+ // The argument tells you which member of the gang you are.
+ virtual void work(int i) = 0;
+
+ int requested_size() const { return _requested_size; }
+ int actual_size() const { return _actual_size; }
+
+ void set_requested_size(int sz) { _requested_size = sz; }
+ void set_actual_size(int sz) { _actual_size = sz; }
+};
+
// An abstract task to be worked on by a flexible work gang,
// and where the workers will periodically yield, usually
// in response to some condition that is signalled by means
@@ -70,19 +89,15 @@
// maximum) in response to task requests at certain points.
// The last part (the flexible part) has not yet been fully
// fleshed out and is a work in progress.
-class YieldingFlexibleGangTask: public AbstractGangTask {
+class YieldingFlexibleGangTask: public FlexibleGangTask {
Status _status;
YieldingFlexibleWorkGang* _gang;
- int _actual_size; // size of gang obtained
protected:
- int _requested_size; // size of gang requested
-
// Constructor and desctructor: only construct subclasses.
- YieldingFlexibleGangTask(const char* name): AbstractGangTask(name),
+ YieldingFlexibleGangTask(const char* name): FlexibleGangTask(name),
_status(INACTIVE),
- _gang(NULL),
- _requested_size(0) { }
+ _gang(NULL) { }
virtual ~YieldingFlexibleGangTask() { }
@@ -122,24 +137,18 @@
virtual void abort();
Status status() const { return _status; }
+ bool yielding() const { return _status == YIELDING; }
bool yielded() const { return _status == YIELDED; }
bool completed() const { return _status == COMPLETED; }
bool aborted() const { return _status == ABORTED; }
bool active() const { return _status == ACTIVE; }
-
- int requested_size() const { return _requested_size; }
- int actual_size() const { return _actual_size; }
-
- void set_requested_size(int sz) { _requested_size = sz; }
- void set_actual_size(int sz) { _actual_size = sz; }
};
-
// Class YieldingWorkGang: A subclass of WorkGang.
// In particular, a YieldingWorkGang is made up of
// YieldingGangWorkers, and provides infrastructure
// supporting yielding to the "GangOverseer",
// being the thread that orchestrates the WorkGang via run_task().
-class YieldingFlexibleWorkGang: public AbstractWorkGang {
+class YieldingFlexibleWorkGang: public FlexibleWorkGang {
// Here's the public interface to this class.
public:
// Constructor and destructor.
@@ -151,6 +160,9 @@
"Incorrect cast");
return (YieldingFlexibleGangTask*)task();
}
+ // Allocate a worker and return a pointer to it.
+ GangWorker* allocate_worker(int which);
+
// Run a task; returns when the task is done, or the workers yield,
// or the task is aborted, or the work gang is terminated via stop().
// A task that has been yielded can be continued via this same interface
@@ -180,10 +192,6 @@
void abort();
private:
- // The currently active workers in this gang.
- // This is a number that is dynamically adjusted by
- // the run_task() method at each subsequent invocation,
- // using data in the YieldingFlexibleGangTask.
int _active_workers;
int _yielded_workers;
void wait_for_gang();
@@ -194,6 +202,7 @@
return _active_workers;
}
+ // Accessors for fields
int yielded_workers() const {
return _yielded_workers;
}