--- a/hotspot/src/cpu/x86/vm/globals_x86.hpp Wed Jan 19 19:24:34 2011 -0800
+++ b/hotspot/src/cpu/x86/vm/globals_x86.hpp Thu Jan 20 13:57:12 2011 -0800
@@ -62,7 +62,7 @@
// due to lack of optimization caused by C++ compiler bugs
define_pd_global(intx, StackShadowPages, SOLARIS_ONLY(20) NOT_SOLARIS(6) DEBUG_ONLY(+2));
#else
-define_pd_global(intx, StackShadowPages, 3 DEBUG_ONLY(+1));
+define_pd_global(intx, StackShadowPages, 3 DEBUG_ONLY(+5));
#endif // AMD64
define_pd_global(intx, PreInflateSpin, 10);
--- a/hotspot/src/share/vm/gc_implementation/g1/concurrentMark.cpp Wed Jan 19 19:24:34 2011 -0800
+++ b/hotspot/src/share/vm/gc_implementation/g1/concurrentMark.cpp Thu Jan 20 13:57:12 2011 -0800
@@ -1,5 +1,5 @@
/*
- * Copyright (c) 2001, 2010, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2001, 2011, 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
@@ -458,6 +458,7 @@
_marking_task_overhead(1.0),
_cleanup_sleep_factor(0.0),
_cleanup_task_overhead(1.0),
+ _cleanup_list("Cleanup List"),
_region_bm(max_regions, false /* in_resource_area*/),
_card_bm((rs.size() + CardTableModRefBS::card_size - 1) >>
CardTableModRefBS::card_shift,
@@ -521,12 +522,6 @@
SATBMarkQueueSet& satb_qs = JavaThread::satb_mark_queue_set();
satb_qs.set_buffer_size(G1SATBBufferSize);
- int size = (int) MAX2(ParallelGCThreads, (size_t)1);
- _par_cleanup_thread_state = NEW_C_HEAP_ARRAY(ParCleanupThreadState*, size);
- for (int i = 0 ; i < size; i++) {
- _par_cleanup_thread_state[i] = new ParCleanupThreadState;
- }
-
_tasks = NEW_C_HEAP_ARRAY(CMTask*, _max_task_num);
_accum_task_vtime = NEW_C_HEAP_ARRAY(double, _max_task_num);
@@ -711,11 +706,6 @@
}
ConcurrentMark::~ConcurrentMark() {
- int size = (int) MAX2(ParallelGCThreads, (size_t)1);
- for (int i = 0; i < size; i++) delete _par_cleanup_thread_state[i];
- FREE_C_HEAP_ARRAY(ParCleanupThreadState*,
- _par_cleanup_thread_state);
-
for (int i = 0; i < (int) _max_task_num; ++i) {
delete _task_queues->queue(i);
delete _tasks[i];
@@ -1171,12 +1161,12 @@
if (G1TraceMarkStackOverflow)
gclog_or_tty->print_cr("\nRemark led to restart for overflow.");
} else {
+ SATBMarkQueueSet& satb_mq_set = JavaThread::satb_mark_queue_set();
// We're done with marking.
// This is the end of the marking cycle, we're expected all
// threads to have SATB queues with active set to true.
- JavaThread::satb_mark_queue_set().set_active_all_threads(
- false, /* new active value */
- true /* expected_active */);
+ satb_mq_set.set_active_all_threads(false, /* new active value */
+ true /* expected_active */);
if (VerifyDuringGC) {
HandleMark hm; // handle scope
@@ -1510,21 +1500,20 @@
size_t _max_live_bytes;
size_t _regions_claimed;
size_t _freed_bytes;
- size_t _cleared_h_regions;
- size_t _freed_regions;
- UncleanRegionList* _unclean_region_list;
+ FreeRegionList _local_cleanup_list;
+ HumongousRegionSet _humongous_proxy_set;
double _claimed_region_time;
double _max_region_time;
public:
G1NoteEndOfConcMarkClosure(G1CollectedHeap* g1,
- UncleanRegionList* list,
int worker_num);
size_t freed_bytes() { return _freed_bytes; }
- size_t cleared_h_regions() { return _cleared_h_regions; }
- size_t freed_regions() { return _freed_regions; }
- UncleanRegionList* unclean_region_list() {
- return _unclean_region_list;
+ FreeRegionList* local_cleanup_list() {
+ return &_local_cleanup_list;
+ }
+ HumongousRegionSet* humongous_proxy_set() {
+ return &_humongous_proxy_set;
}
bool doHeapRegion(HeapRegion *r);
@@ -1537,25 +1526,22 @@
class G1ParNoteEndTask: public AbstractGangTask {
friend class G1NoteEndOfConcMarkClosure;
+
protected:
G1CollectedHeap* _g1h;
size_t _max_live_bytes;
size_t _freed_bytes;
- ConcurrentMark::ParCleanupThreadState** _par_cleanup_thread_state;
+ FreeRegionList* _cleanup_list;
+
public:
G1ParNoteEndTask(G1CollectedHeap* g1h,
- ConcurrentMark::ParCleanupThreadState**
- par_cleanup_thread_state) :
+ FreeRegionList* cleanup_list) :
AbstractGangTask("G1 note end"), _g1h(g1h),
- _max_live_bytes(0), _freed_bytes(0),
- _par_cleanup_thread_state(par_cleanup_thread_state)
- {}
+ _max_live_bytes(0), _freed_bytes(0), _cleanup_list(cleanup_list) { }
void work(int i) {
double start = os::elapsedTime();
- G1NoteEndOfConcMarkClosure g1_note_end(_g1h,
- &_par_cleanup_thread_state[i]->list,
- i);
+ G1NoteEndOfConcMarkClosure g1_note_end(_g1h, i);
if (G1CollectedHeap::use_parallel_gc_threads()) {
_g1h->heap_region_par_iterate_chunked(&g1_note_end, i,
HeapRegion::NoteEndClaimValue);
@@ -1564,14 +1550,18 @@
}
assert(g1_note_end.complete(), "Shouldn't have yielded!");
- // Now finish up freeing the current thread's regions.
- _g1h->finish_free_region_work(g1_note_end.freed_bytes(),
- g1_note_end.cleared_h_regions(),
- 0, NULL);
+ // Now update the lists
+ _g1h->update_sets_after_freeing_regions(g1_note_end.freed_bytes(),
+ NULL /* free_list */,
+ g1_note_end.humongous_proxy_set(),
+ true /* par */);
{
MutexLockerEx x(ParGCRareEvent_lock, Mutex::_no_safepoint_check_flag);
_max_live_bytes += g1_note_end.max_live_bytes();
_freed_bytes += g1_note_end.freed_bytes();
+
+ _cleanup_list->add_as_tail(g1_note_end.local_cleanup_list());
+ assert(g1_note_end.local_cleanup_list()->is_empty(), "post-condition");
}
double end = os::elapsedTime();
if (G1PrintParCleanupStats) {
@@ -1612,30 +1602,28 @@
G1NoteEndOfConcMarkClosure::
G1NoteEndOfConcMarkClosure(G1CollectedHeap* g1,
- UncleanRegionList* list,
int worker_num)
: _g1(g1), _worker_num(worker_num),
_max_live_bytes(0), _regions_claimed(0),
- _freed_bytes(0), _cleared_h_regions(0), _freed_regions(0),
+ _freed_bytes(0),
_claimed_region_time(0.0), _max_region_time(0.0),
- _unclean_region_list(list)
-{}
-
-bool G1NoteEndOfConcMarkClosure::doHeapRegion(HeapRegion *r) {
+ _local_cleanup_list("Local Cleanup List"),
+ _humongous_proxy_set("Local Cleanup Humongous Proxy Set") { }
+
+bool G1NoteEndOfConcMarkClosure::doHeapRegion(HeapRegion *hr) {
// We use a claim value of zero here because all regions
// were claimed with value 1 in the FinalCount task.
- r->reset_gc_time_stamp();
- if (!r->continuesHumongous()) {
+ hr->reset_gc_time_stamp();
+ if (!hr->continuesHumongous()) {
double start = os::elapsedTime();
_regions_claimed++;
- r->note_end_of_marking();
- _max_live_bytes += r->max_live_bytes();
- _g1->free_region_if_totally_empty_work(r,
- _freed_bytes,
- _cleared_h_regions,
- _freed_regions,
- _unclean_region_list,
- true /*par*/);
+ hr->note_end_of_marking();
+ _max_live_bytes += hr->max_live_bytes();
+ _g1->free_region_if_totally_empty(hr,
+ &_freed_bytes,
+ &_local_cleanup_list,
+ &_humongous_proxy_set,
+ true /* par */);
double region_time = (os::elapsedTime() - start);
_claimed_region_time += region_time;
if (region_time > _max_region_time) _max_region_time = region_time;
@@ -1655,6 +1643,8 @@
return;
}
+ g1h->verify_region_sets_optional();
+
if (VerifyDuringGC) {
HandleMark hm; // handle scope
gclog_or_tty->print(" VerifyDuringGC:(before)");
@@ -1719,7 +1709,7 @@
// 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);
+ G1ParNoteEndTask g1_par_note_end_task(g1h, &_cleanup_list);
if (G1CollectedHeap::use_parallel_gc_threads()) {
int n_workers = g1h->workers()->total_workers();
g1h->set_par_threads(n_workers);
@@ -1731,9 +1721,14 @@
} else {
g1_par_note_end_task.work(0);
}
- g1h->set_unclean_regions_coming(true);
+
+ if (!cleanup_list_is_empty()) {
+ // The cleanup list is not empty, so we'll have to process it
+ // concurrently. Notify anyone else that might be wanting free
+ // regions that there will be more free regions coming soon.
+ g1h->set_free_regions_coming();
+ }
double note_end_end = os::elapsedTime();
- // Tell the mutators that there might be unclean regions coming...
if (G1PrintParCleanupStats) {
gclog_or_tty->print_cr(" note end of marking: %8.3f ms.",
(note_end_end - note_end_start)*1000.0);
@@ -1799,33 +1794,63 @@
/* silent */ false,
/* prev marking */ true);
}
+
+ g1h->verify_region_sets_optional();
}
void ConcurrentMark::completeCleanup() {
- // A full collection intervened.
if (has_aborted()) return;
- int first = 0;
- int last = (int)MAX2(ParallelGCThreads, (size_t)1);
- for (int t = 0; t < last; t++) {
- UncleanRegionList* list = &_par_cleanup_thread_state[t]->list;
- assert(list->well_formed(), "Inv");
- HeapRegion* hd = list->hd();
- while (hd != NULL) {
- // Now finish up the other stuff.
- hd->rem_set()->clear();
- HeapRegion* next_hd = hd->next_from_unclean_list();
- (void)list->pop();
- assert(list->hd() == next_hd, "how not?");
- _g1h->put_region_on_unclean_list(hd);
- if (!hd->isHumongous()) {
- // Add this to the _free_regions count by 1.
- _g1h->finish_free_region_work(0, 0, 1, NULL);
+ G1CollectedHeap* g1h = G1CollectedHeap::heap();
+
+ _cleanup_list.verify_optional();
+ FreeRegionList local_free_list("Local Cleanup List");
+
+ if (G1ConcRegionFreeingVerbose) {
+ gclog_or_tty->print_cr("G1ConcRegionFreeing [complete cleanup] : "
+ "cleanup list has "SIZE_FORMAT" entries",
+ _cleanup_list.length());
+ }
+
+ // Noone else should be accessing the _cleanup_list at this point,
+ // so it's not necessary to take any locks
+ while (!_cleanup_list.is_empty()) {
+ HeapRegion* hr = _cleanup_list.remove_head();
+ assert(hr != NULL, "the list was not empty");
+ hr->rem_set()->clear();
+ local_free_list.add_as_tail(hr);
+
+ // Instead of adding one region at a time to the secondary_free_list,
+ // we accumulate them in the local list and move them a few at a
+ // time. This also cuts down on the number of notify_all() calls
+ // we do during this process. We'll also append the local list when
+ // _cleanup_list is empty (which means we just removed the last
+ // region from the _cleanup_list).
+ if ((local_free_list.length() % G1SecondaryFreeListAppendLength == 0) ||
+ _cleanup_list.is_empty()) {
+ if (G1ConcRegionFreeingVerbose) {
+ gclog_or_tty->print_cr("G1ConcRegionFreeing [complete cleanup] : "
+ "appending "SIZE_FORMAT" entries to the "
+ "secondary_free_list, clean list still has "
+ SIZE_FORMAT" entries",
+ local_free_list.length(),
+ _cleanup_list.length());
}
- hd = list->hd();
- assert(hd == next_hd, "how not?");
+
+ {
+ MutexLockerEx x(SecondaryFreeList_lock, Mutex::_no_safepoint_check_flag);
+ g1h->secondary_free_list_add_as_tail(&local_free_list);
+ SecondaryFreeList_lock->notify_all();
+ }
+
+ if (G1StressConcRegionFreeing) {
+ for (uintx i = 0; i < G1StressConcRegionFreeingDelayMillis; ++i) {
+ os::sleep(Thread::current(), (jlong) 1, false);
+ }
+ }
}
}
+ assert(local_free_list.is_empty(), "post-condition");
}
bool G1CMIsAliveClosure::do_object_b(oop obj) {
@@ -2897,9 +2922,9 @@
virtual void do_oop( oop* p) { do_oop_work(p); }
template <class T> void do_oop_work(T* p) {
- assert(_g1h->is_in_g1_reserved((HeapWord*) p), "invariant");
- assert(!_g1h->heap_region_containing((HeapWord*) p)->is_on_free_list(),
- "invariant");
+ assert( _g1h->is_in_g1_reserved((HeapWord*) p), "invariant");
+ assert(!_g1h->is_on_free_list(
+ _g1h->heap_region_containing((HeapWord*) p)), "invariant");
oop obj = oopDesc::load_decode_heap_oop(p);
if (_cm->verbose_high())
@@ -3119,8 +3144,8 @@
void CMTask::push(oop obj) {
HeapWord* objAddr = (HeapWord*) obj;
assert(_g1h->is_in_g1_reserved(objAddr), "invariant");
- assert(!_g1h->heap_region_containing(objAddr)->is_on_free_list(),
- "invariant");
+ assert(!_g1h->is_on_free_list(
+ _g1h->heap_region_containing((HeapWord*) objAddr)), "invariant");
assert(!_g1h->is_obj_ill(obj), "invariant");
assert(_nextMarkBitMap->isMarked(objAddr), "invariant");
@@ -3365,8 +3390,8 @@
(void*) obj);
assert(_g1h->is_in_g1_reserved((HeapWord*) obj), "invariant" );
- assert(!_g1h->heap_region_containing(obj)->is_on_free_list(),
- "invariant");
+ assert(!_g1h->is_on_free_list(
+ _g1h->heap_region_containing((HeapWord*) obj)), "invariant");
scan_object(obj);
--- a/hotspot/src/share/vm/gc_implementation/g1/concurrentMark.hpp Wed Jan 19 19:24:34 2011 -0800
+++ b/hotspot/src/share/vm/gc_implementation/g1/concurrentMark.hpp Thu Jan 20 13:57:12 2011 -0800
@@ -1,5 +1,5 @@
/*
- * Copyright (c) 2001, 2010, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2001, 2011, 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
@@ -25,7 +25,7 @@
#ifndef SHARE_VM_GC_IMPLEMENTATION_G1_CONCURRENTMARK_HPP
#define SHARE_VM_GC_IMPLEMENTATION_G1_CONCURRENTMARK_HPP
-#include "gc_implementation/g1/heapRegion.hpp"
+#include "gc_implementation/g1/heapRegionSets.hpp"
#include "utilities/taskqueue.hpp"
class G1CollectedHeap;
@@ -369,13 +369,7 @@
double _cleanup_sleep_factor;
double _cleanup_task_overhead;
- // Stuff related to age cohort processing.
- struct ParCleanupThreadState {
- char _pre[64];
- UncleanRegionList list;
- char _post[64];
- };
- ParCleanupThreadState** _par_cleanup_thread_state;
+ FreeRegionList _cleanup_list;
// CMS marking support structures
CMBitMap _markBitMap1;
@@ -484,6 +478,10 @@
// prints all gathered CM-related statistics
void print_stats();
+ bool cleanup_list_is_empty() {
+ return _cleanup_list.is_empty();
+ }
+
// accessor methods
size_t parallel_marking_threads() { return _parallel_marking_threads; }
double sleep_factor() { return _sleep_factor; }
--- a/hotspot/src/share/vm/gc_implementation/g1/concurrentMarkThread.cpp Wed Jan 19 19:24:34 2011 -0800
+++ b/hotspot/src/share/vm/gc_implementation/g1/concurrentMarkThread.cpp Thu Jan 20 13:57:12 2011 -0800
@@ -1,5 +1,5 @@
/*
- * Copyright (c) 2001, 2010, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2001, 2011, 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
@@ -95,8 +95,8 @@
_vtime_start = os::elapsedVTime();
wait_for_universe_init();
- G1CollectedHeap* g1 = G1CollectedHeap::heap();
- G1CollectorPolicy* g1_policy = g1->g1_policy();
+ G1CollectedHeap* g1h = G1CollectedHeap::heap();
+ G1CollectorPolicy* g1_policy = g1h->g1_policy();
G1MMUTracker *mmu_tracker = g1_policy->mmu_tracker();
Thread *current_thread = Thread::current();
@@ -119,7 +119,7 @@
if (!g1_policy->in_young_gc_mode()) {
// this ensures the flag is not set if we bail out of the marking
// cycle; normally the flag is cleared immediately after cleanup
- g1->set_marking_complete();
+ g1h->set_marking_complete();
if (g1_policy->adaptive_young_list_length()) {
double now = os::elapsedTime();
@@ -228,10 +228,20 @@
VM_CGC_Operation op(&cl_cl, verbose_str);
VMThread::execute(&op);
} else {
- G1CollectedHeap::heap()->set_marking_complete();
+ g1h->set_marking_complete();
}
- if (!cm()->has_aborted()) {
+ // Check if cleanup set the free_regions_coming flag. If it
+ // hasn't, we can just skip the next step.
+ if (g1h->free_regions_coming()) {
+ // The following will finish freeing up any regions that we
+ // found to be empty during cleanup. We'll do this part
+ // without joining the suspendible set. If an evacuation pause
+ // takes places, then we would carry on freeing regions in
+ // case they are needed by the pause. If a Full GC takes
+ // places, it would wait for us to process the regions
+ // reclaimed by cleanup.
+
double cleanup_start_sec = os::elapsedTime();
if (PrintGC) {
gclog_or_tty->date_stamp(PrintGCDateStamps);
@@ -240,23 +250,22 @@
}
// Now do the remainder of the cleanup operation.
- _sts.join();
_cm->completeCleanup();
- if (!cm()->has_aborted()) {
- g1_policy->record_concurrent_mark_cleanup_completed();
+ g1_policy->record_concurrent_mark_cleanup_completed();
- double cleanup_end_sec = os::elapsedTime();
- if (PrintGC) {
- gclog_or_tty->date_stamp(PrintGCDateStamps);
- gclog_or_tty->stamp(PrintGCTimeStamps);
- gclog_or_tty->print_cr("[GC concurrent-cleanup-end, %1.7lf]",
- cleanup_end_sec - cleanup_start_sec);
- }
+ double cleanup_end_sec = os::elapsedTime();
+ if (PrintGC) {
+ gclog_or_tty->date_stamp(PrintGCDateStamps);
+ gclog_or_tty->stamp(PrintGCTimeStamps);
+ gclog_or_tty->print_cr("[GC concurrent-cleanup-end, %1.7lf]",
+ cleanup_end_sec - cleanup_start_sec);
}
- _sts.leave();
+
+ // We're done: no more free regions coming.
+ g1h->reset_free_regions_coming();
}
- // We're done: no more unclean regions coming.
- G1CollectedHeap::heap()->set_unclean_regions_coming(false);
+ guarantee(cm()->cleanup_list_is_empty(),
+ "at this point there should be no regions on the cleanup list");
if (cm()->has_aborted()) {
if (PrintGC) {
@@ -278,7 +287,7 @@
// Java thread is waiting for a full GC to happen (e.g., it
// called System.gc() with +ExplicitGCInvokesConcurrent).
_sts.join();
- g1->increment_full_collections_completed(true /* concurrent */);
+ g1h->increment_full_collections_completed(true /* concurrent */);
_sts.leave();
}
assert(_should_terminate, "just checking");
--- a/hotspot/src/share/vm/gc_implementation/g1/concurrentZFThread.cpp Wed Jan 19 19:24:34 2011 -0800
+++ /dev/null Thu Jan 01 00:00:00 1970 +0000
@@ -1,194 +0,0 @@
-/*
- * 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
- * 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 Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
- * or visit www.oracle.com if you need additional information or have any
- * questions.
- *
- */
-
-#include "precompiled.hpp"
-#include "gc_implementation/g1/concurrentZFThread.hpp"
-#include "gc_implementation/g1/g1CollectedHeap.inline.hpp"
-#include "gc_implementation/g1/heapRegion.hpp"
-#include "memory/space.inline.hpp"
-#include "runtime/mutexLocker.hpp"
-#include "utilities/copy.hpp"
-
-// ======= Concurrent Zero-Fill Thread ========
-
-// The CM thread is created when the G1 garbage collector is used
-
-int ConcurrentZFThread::_region_allocs = 0;
-int ConcurrentZFThread::_sync_zfs = 0;
-int ConcurrentZFThread::_zf_waits = 0;
-int ConcurrentZFThread::_regions_filled = 0;
-
-ConcurrentZFThread::ConcurrentZFThread() :
- ConcurrentGCThread()
-{
- create_and_start();
-}
-
-void ConcurrentZFThread::wait_for_ZF_completed(HeapRegion* hr) {
- assert(ZF_mon->owned_by_self(), "Precondition.");
- note_zf_wait();
- while (hr->zero_fill_state() == HeapRegion::ZeroFilling) {
- ZF_mon->wait(Mutex::_no_safepoint_check_flag);
- }
-}
-
-void ConcurrentZFThread::processHeapRegion(HeapRegion* hr) {
- assert(!Universe::heap()->is_gc_active(),
- "This should not happen during GC.");
- assert(hr != NULL, "Precondition");
- // These are unlocked reads, but if this test is successful, then no
- // other thread will attempt this zero filling. Only a GC thread can
- // modify the ZF state of a region whose state is zero-filling, and this
- // should only happen while the ZF thread is locking out GC.
- if (hr->zero_fill_state() == HeapRegion::ZeroFilling
- && hr->zero_filler() == Thread::current()) {
- assert(hr->top() == hr->bottom(), "better be empty!");
- assert(!hr->isHumongous(), "Only free regions on unclean list.");
- Copy::fill_to_words(hr->bottom(), hr->capacity()/HeapWordSize);
- note_region_filled();
- }
-}
-
-void ConcurrentZFThread::run() {
- initialize_in_thread();
- Thread* thr_self = Thread::current();
- _vtime_start = os::elapsedVTime();
- wait_for_universe_init();
-
- G1CollectedHeap* g1 = G1CollectedHeap::heap();
- _sts.join();
- while (!_should_terminate) {
- _sts.leave();
-
- {
- MutexLockerEx x(ZF_mon, Mutex::_no_safepoint_check_flag);
-
- // This local variable will hold a region being zero-filled. This
- // region will neither be on the unclean or zero-filled lists, and
- // will not be available for allocation; thus, we might have an
- // allocation fail, causing a full GC, because of this, but this is a
- // price we will pay. (In future, we might want to make the fact
- // that there's a region being zero-filled apparent to the G1 heap,
- // which could then wait for it in this extreme case...)
- HeapRegion* to_fill;
-
- while (!g1->should_zf()
- || (to_fill = g1->pop_unclean_region_list_locked()) == NULL)
- ZF_mon->wait(Mutex::_no_safepoint_check_flag);
- while (to_fill->zero_fill_state() == HeapRegion::ZeroFilling)
- ZF_mon->wait(Mutex::_no_safepoint_check_flag);
-
- // So now to_fill is non-NULL and is not ZeroFilling. It might be
- // Allocated or ZeroFilled. (The latter could happen if this thread
- // starts the zero-filling of a region, but a GC intervenes and
- // pushes new regions needing on the front of the filling on the
- // front of the list.)
-
- switch (to_fill->zero_fill_state()) {
- case HeapRegion::Allocated:
- to_fill = NULL;
- break;
-
- case HeapRegion::NotZeroFilled:
- to_fill->set_zero_fill_in_progress(thr_self);
-
- ZF_mon->unlock();
- _sts.join();
- processHeapRegion(to_fill);
- _sts.leave();
- ZF_mon->lock_without_safepoint_check();
-
- if (to_fill->zero_fill_state() == HeapRegion::ZeroFilling
- && to_fill->zero_filler() == thr_self) {
- to_fill->set_zero_fill_complete();
- (void)g1->put_free_region_on_list_locked(to_fill);
- }
- break;
-
- case HeapRegion::ZeroFilled:
- (void)g1->put_free_region_on_list_locked(to_fill);
- break;
-
- case HeapRegion::ZeroFilling:
- ShouldNotReachHere();
- break;
- }
- }
- _vtime_accum = (os::elapsedVTime() - _vtime_start);
- _sts.join();
- }
- _sts.leave();
-
- assert(_should_terminate, "just checking");
- terminate();
-}
-
-bool ConcurrentZFThread::offer_yield() {
- if (_sts.should_yield()) {
- _sts.yield("Concurrent ZF");
- return true;
- } else {
- return false;
- }
-}
-
-void ConcurrentZFThread::stop() {
- // it is ok to take late safepoints here, if needed
- MutexLockerEx mu(Terminator_lock);
- _should_terminate = true;
- while (!_has_terminated) {
- Terminator_lock->wait();
- }
-}
-
-void ConcurrentZFThread::print() const {
- print_on(tty);
-}
-
-void ConcurrentZFThread::print_on(outputStream* st) const {
- st->print("\"G1 Concurrent Zero-Fill Thread\" ");
- Thread::print_on(st);
- st->cr();
-}
-
-
-double ConcurrentZFThread::_vtime_accum;
-
-void ConcurrentZFThread::print_summary_info() {
- gclog_or_tty->print("\nConcurrent Zero-Filling:\n");
- gclog_or_tty->print(" Filled %d regions, used %5.2fs.\n",
- _regions_filled,
- vtime_accum());
- gclog_or_tty->print(" Of %d region allocs, %d (%5.2f%%) required sync ZF,\n",
- _region_allocs, _sync_zfs,
- (_region_allocs > 0 ?
- (float)_sync_zfs/(float)_region_allocs*100.0 :
- 0.0));
- gclog_or_tty->print(" and %d (%5.2f%%) required a ZF wait.\n",
- _zf_waits,
- (_region_allocs > 0 ?
- (float)_zf_waits/(float)_region_allocs*100.0 :
- 0.0));
-
-}
--- a/hotspot/src/share/vm/gc_implementation/g1/concurrentZFThread.hpp Wed Jan 19 19:24:34 2011 -0800
+++ /dev/null Thu Jan 01 00:00:00 1970 +0000
@@ -1,91 +0,0 @@
-/*
- * 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
- * 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 Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
- * or visit www.oracle.com if you need additional information or have any
- * questions.
- *
- */
-
-#ifndef SHARE_VM_GC_IMPLEMENTATION_G1_CONCURRENTZFTHREAD_HPP
-#define SHARE_VM_GC_IMPLEMENTATION_G1_CONCURRENTZFTHREAD_HPP
-
-#include "gc_implementation/shared/concurrentGCThread.hpp"
-
-// The Concurrent ZF Thread. Performs concurrent zero-filling.
-
-class ConcurrentZFThread: public ConcurrentGCThread {
- friend class VMStructs;
- friend class ZeroFillRegionClosure;
-
- private:
-
- // Zero fill the heap region.
- void processHeapRegion(HeapRegion* r);
-
- // Stats
- // Allocation (protected by heap lock).
- static int _region_allocs; // Number of regions allocated
- static int _sync_zfs; // Synchronous zero-fills +
- static int _zf_waits; // Wait for conc zero-fill completion.
-
- // Number of regions CFZ thread fills.
- static int _regions_filled;
-
- double _vtime_start; // Initial virtual time.
-
- // These are static because the "print_summary_info" method is, and
- // it currently assumes there is only one ZF thread. We'll change when
- // we need to.
- static double _vtime_accum; // Initial virtual time.
- static double vtime_accum() { return _vtime_accum; }
-
- // Offer yield for GC. Returns true if yield occurred.
- bool offer_yield();
-
- public:
- // Constructor
- ConcurrentZFThread();
-
- // Main loop.
- virtual void run();
-
- // Printing
- void print_on(outputStream* st) const;
- void print() const;
-
- // Waits until "r" has been zero-filled. Requires caller to hold the
- // ZF_mon.
- static void wait_for_ZF_completed(HeapRegion* r);
-
- // Get or clear the current unclean region. Should be done
- // while holding the ZF_needed_mon lock.
-
- // shutdown
- void stop();
-
- // Stats
- static void note_region_alloc() {_region_allocs++; }
- static void note_sync_zfs() { _sync_zfs++; }
- static void note_zf_wait() { _zf_waits++; }
- static void note_region_filled() { _regions_filled++; }
-
- static void print_summary_info();
-};
-
-#endif // SHARE_VM_GC_IMPLEMENTATION_G1_CONCURRENTZFTHREAD_HPP
--- a/hotspot/src/share/vm/gc_implementation/g1/g1CollectedHeap.cpp Wed Jan 19 19:24:34 2011 -0800
+++ b/hotspot/src/share/vm/gc_implementation/g1/g1CollectedHeap.cpp Thu Jan 20 13:57:12 2011 -0800
@@ -28,7 +28,6 @@
#include "gc_implementation/g1/concurrentG1Refine.hpp"
#include "gc_implementation/g1/concurrentG1RefineThread.hpp"
#include "gc_implementation/g1/concurrentMarkThread.inline.hpp"
-#include "gc_implementation/g1/concurrentZFThread.hpp"
#include "gc_implementation/g1/g1CollectedHeap.inline.hpp"
#include "gc_implementation/g1/g1CollectorPolicy.hpp"
#include "gc_implementation/g1/g1MarkSweep.hpp"
@@ -425,11 +424,9 @@
void G1CollectedHeap::stop_conc_gc_threads() {
_cg1r->stop();
- _czft->stop();
_cmThread->stop();
}
-
void G1CollectedHeap::check_ct_logs_at_safepoint() {
DirtyCardQueueSet& dcqs = JavaThread::dirty_card_queue_set();
CardTableModRefBS* ct_bs = (CardTableModRefBS*)barrier_set();
@@ -481,49 +478,92 @@
// Private methods.
-// Finds a HeapRegion that can be used to allocate a given size of block.
-
-
-HeapRegion* G1CollectedHeap::newAllocRegion_work(size_t word_size,
- bool do_expand,
- bool zero_filled) {
- ConcurrentZFThread::note_region_alloc();
- HeapRegion* res = alloc_free_region_from_lists(zero_filled);
+HeapRegion*
+G1CollectedHeap::new_region_try_secondary_free_list(size_t word_size) {
+ MutexLockerEx x(SecondaryFreeList_lock, Mutex::_no_safepoint_check_flag);
+ while (!_secondary_free_list.is_empty() || free_regions_coming()) {
+ if (!_secondary_free_list.is_empty()) {
+ if (G1ConcRegionFreeingVerbose) {
+ gclog_or_tty->print_cr("G1ConcRegionFreeing [region alloc] : "
+ "secondary_free_list has "SIZE_FORMAT" entries",
+ _secondary_free_list.length());
+ }
+ // It looks as if there are free regions available on the
+ // secondary_free_list. Let's move them to the free_list and try
+ // again to allocate from it.
+ append_secondary_free_list();
+
+ assert(!_free_list.is_empty(), "if the secondary_free_list was not "
+ "empty we should have moved at least one entry to the free_list");
+ HeapRegion* res = _free_list.remove_head();
+ if (G1ConcRegionFreeingVerbose) {
+ gclog_or_tty->print_cr("G1ConcRegionFreeing [region alloc] : "
+ "allocated "HR_FORMAT" from secondary_free_list",
+ HR_FORMAT_PARAMS(res));
+ }
+ return res;
+ }
+
+ // Wait here until we get notifed either when (a) there are no
+ // more free regions coming or (b) some regions have been moved on
+ // the secondary_free_list.
+ SecondaryFreeList_lock->wait(Mutex::_no_safepoint_check_flag);
+ }
+
+ if (G1ConcRegionFreeingVerbose) {
+ gclog_or_tty->print_cr("G1ConcRegionFreeing [region alloc] : "
+ "could not allocate from secondary_free_list");
+ }
+ return NULL;
+}
+
+HeapRegion* G1CollectedHeap::new_region_work(size_t word_size,
+ bool do_expand) {
+ assert(!isHumongous(word_size) ||
+ word_size <= (size_t) HeapRegion::GrainWords,
+ "the only time we use this to allocate a humongous region is "
+ "when we are allocating a single humongous region");
+
+ HeapRegion* res;
+ if (G1StressConcRegionFreeing) {
+ if (!_secondary_free_list.is_empty()) {
+ if (G1ConcRegionFreeingVerbose) {
+ gclog_or_tty->print_cr("G1ConcRegionFreeing [region alloc] : "
+ "forced to look at the secondary_free_list");
+ }
+ res = new_region_try_secondary_free_list(word_size);
+ if (res != NULL) {
+ return res;
+ }
+ }
+ }
+ res = _free_list.remove_head_or_null();
+ if (res == NULL) {
+ if (G1ConcRegionFreeingVerbose) {
+ gclog_or_tty->print_cr("G1ConcRegionFreeing [region alloc] : "
+ "res == NULL, trying the secondary_free_list");
+ }
+ res = new_region_try_secondary_free_list(word_size);
+ }
if (res == NULL && do_expand) {
expand(word_size * HeapWordSize);
- res = alloc_free_region_from_lists(zero_filled);
- assert(res == NULL ||
- (!res->isHumongous() &&
- (!zero_filled ||
- res->zero_fill_state() == HeapRegion::Allocated)),
- "Alloc Regions must be zero filled (and non-H)");
+ res = _free_list.remove_head_or_null();
}
if (res != NULL) {
- if (res->is_empty()) {
- _free_regions--;
- }
- assert(!res->isHumongous() &&
- (!zero_filled || res->zero_fill_state() == HeapRegion::Allocated),
- err_msg("Non-young alloc Regions must be zero filled (and non-H):"
- " res->isHumongous()=%d, zero_filled=%d, res->zero_fill_state()=%d",
- res->isHumongous(), zero_filled, res->zero_fill_state()));
- assert(!res->is_on_unclean_list(),
- "Alloc Regions must not be on the unclean list");
if (G1PrintHeapRegions) {
- gclog_or_tty->print_cr("new alloc region %d:["PTR_FORMAT", "PTR_FORMAT"], "
- "top "PTR_FORMAT,
- res->hrs_index(), res->bottom(), res->end(), res->top());
+ gclog_or_tty->print_cr("new alloc region %d:["PTR_FORMAT","PTR_FORMAT"], "
+ "top "PTR_FORMAT, res->hrs_index(),
+ res->bottom(), res->end(), res->top());
}
}
return res;
}
-HeapRegion* G1CollectedHeap::newAllocRegionWithExpansion(int purpose,
- size_t word_size,
- bool zero_filled) {
+HeapRegion* G1CollectedHeap::new_gc_alloc_region(int purpose,
+ size_t word_size) {
HeapRegion* alloc_region = NULL;
if (_gc_alloc_region_counts[purpose] < g1_policy()->max_regions(purpose)) {
- alloc_region = newAllocRegion_work(word_size, true, zero_filled);
+ alloc_region = new_region_work(word_size, true /* do_expand */);
if (purpose == GCAllocForSurvived && alloc_region != NULL) {
alloc_region->set_survivor();
}
@@ -534,82 +574,188 @@
return alloc_region;
}
+int G1CollectedHeap::humongous_obj_allocate_find_first(size_t num_regions,
+ size_t word_size) {
+ int first = -1;
+ if (num_regions == 1) {
+ // Only one region to allocate, no need to go through the slower
+ // path. The caller will attempt the expasion if this fails, so
+ // let's not try to expand here too.
+ HeapRegion* hr = new_region_work(word_size, false /* do_expand */);
+ if (hr != NULL) {
+ first = hr->hrs_index();
+ } else {
+ first = -1;
+ }
+ } else {
+ // We can't allocate humongous regions while cleanupComplete() is
+ // running, since some of the regions we find to be empty might not
+ // yet be added to the free list and it is not straightforward to
+ // know which list they are on so that we can remove them. Note
+ // that we only need to do this if we need to allocate more than
+ // one region to satisfy the current humongous allocation
+ // request. If we are only allocating one region we use the common
+ // region allocation code (see above).
+ wait_while_free_regions_coming();
+ append_secondary_free_list_if_not_empty();
+
+ if (free_regions() >= num_regions) {
+ first = _hrs->find_contiguous(num_regions);
+ if (first != -1) {
+ for (int i = first; i < first + (int) num_regions; ++i) {
+ HeapRegion* hr = _hrs->at(i);
+ assert(hr->is_empty(), "sanity");
+ assert(is_on_free_list(hr), "sanity");
+ hr->set_pending_removal(true);
+ }
+ _free_list.remove_all_pending(num_regions);
+ }
+ }
+ }
+ return first;
+}
+
// If could fit into free regions w/o expansion, try.
// Otherwise, if can expand, do so.
// Otherwise, if using ex regions might help, try with ex given back.
HeapWord* G1CollectedHeap::humongous_obj_allocate(size_t word_size) {
- assert_heap_locked_or_at_safepoint();
- assert(regions_accounted_for(), "Region leakage!");
-
- // We can't allocate humongous regions while cleanupComplete is
- // running, since some of the regions we find to be empty might not
- // yet be added to the unclean list. If we're already at a
- // safepoint, this call is unnecessary, not to mention wrong.
- if (!SafepointSynchronize::is_at_safepoint()) {
- wait_for_cleanup_complete();
- }
+ assert_heap_locked_or_at_safepoint(true /* should_be_vm_thread */);
+
+ verify_region_sets_optional();
size_t num_regions =
round_to(word_size, HeapRegion::GrainWords) / HeapRegion::GrainWords;
-
- // Special case if < one region???
-
- // Remember the ft size.
size_t x_size = expansion_regions();
-
- HeapWord* res = NULL;
- bool eliminated_allocated_from_lists = false;
-
- // Can the allocation potentially fit in the free regions?
- if (free_regions() >= num_regions) {
- res = _hrs->obj_allocate(word_size);
- }
- if (res == NULL) {
- // Try expansion.
- size_t fs = _hrs->free_suffix();
+ size_t fs = _hrs->free_suffix();
+ int first = humongous_obj_allocate_find_first(num_regions, word_size);
+ if (first == -1) {
+ // The only thing we can do now is attempt expansion.
if (fs + x_size >= num_regions) {
expand((num_regions - fs) * HeapRegion::GrainBytes);
- res = _hrs->obj_allocate(word_size);
- assert(res != NULL, "This should have worked.");
- } else {
- // Expansion won't help. Are there enough free regions if we get rid
- // of reservations?
- size_t avail = free_regions();
- if (avail >= num_regions) {
- res = _hrs->obj_allocate(word_size);
- if (res != NULL) {
- remove_allocated_regions_from_lists();
- eliminated_allocated_from_lists = true;
- }
+ first = humongous_obj_allocate_find_first(num_regions, word_size);
+ assert(first != -1, "this should have worked");
+ }
+ }
+
+ if (first != -1) {
+ // Index of last region in the series + 1.
+ int last = first + (int) num_regions;
+
+ // We need to initialize the region(s) we just discovered. This is
+ // a bit tricky given that it can happen concurrently with
+ // refinement threads refining cards on these regions and
+ // potentially wanting to refine the BOT as they are scanning
+ // those cards (this can happen shortly after a cleanup; see CR
+ // 6991377). So we have to set up the region(s) carefully and in
+ // a specific order.
+
+ // The word size sum of all the regions we will allocate.
+ size_t word_size_sum = num_regions * HeapRegion::GrainWords;
+ assert(word_size <= word_size_sum, "sanity");
+
+ // This will be the "starts humongous" region.
+ HeapRegion* first_hr = _hrs->at(first);
+ // The header of the new object will be placed at the bottom of
+ // the first region.
+ HeapWord* new_obj = first_hr->bottom();
+ // This will be the new end of the first region in the series that
+ // should also match the end of the last region in the seriers.
+ HeapWord* new_end = new_obj + word_size_sum;
+ // This will be the new top of the first region that will reflect
+ // this allocation.
+ HeapWord* new_top = new_obj + word_size;
+
+ // First, we need to zero the header of the space that we will be
+ // allocating. When we update top further down, some refinement
+ // threads might try to scan the region. By zeroing the header we
+ // ensure that any thread that will try to scan the region will
+ // come across the zero klass word and bail out.
+ //
+ // NOTE: It would not have been correct to have used
+ // CollectedHeap::fill_with_object() and make the space look like
+ // an int array. The thread that is doing the allocation will
+ // later update the object header to a potentially different array
+ // type and, for a very short period of time, the klass and length
+ // fields will be inconsistent. This could cause a refinement
+ // thread to calculate the object size incorrectly.
+ Copy::fill_to_words(new_obj, oopDesc::header_size(), 0);
+
+ // We will set up the first region as "starts humongous". This
+ // will also update the BOT covering all the regions to reflect
+ // that there is a single object that starts at the bottom of the
+ // first region.
+ first_hr->set_startsHumongous(new_top, new_end);
+
+ // Then, if there are any, we will set up the "continues
+ // humongous" regions.
+ HeapRegion* hr = NULL;
+ for (int i = first + 1; i < last; ++i) {
+ hr = _hrs->at(i);
+ hr->set_continuesHumongous(first_hr);
+ }
+ // If we have "continues humongous" regions (hr != NULL), then the
+ // end of the last one should match new_end.
+ assert(hr == NULL || hr->end() == new_end, "sanity");
+
+ // Up to this point no concurrent thread would have been able to
+ // do any scanning on any region in this series. All the top
+ // fields still point to bottom, so the intersection between
+ // [bottom,top] and [card_start,card_end] will be empty. Before we
+ // update the top fields, we'll do a storestore to make sure that
+ // no thread sees the update to top before the zeroing of the
+ // object header and the BOT initialization.
+ OrderAccess::storestore();
+
+ // Now that the BOT and the object header have been initialized,
+ // we can update top of the "starts humongous" region.
+ assert(first_hr->bottom() < new_top && new_top <= first_hr->end(),
+ "new_top should be in this region");
+ first_hr->set_top(new_top);
+
+ // Now, we will update the top fields of the "continues humongous"
+ // regions. The reason we need to do this is that, otherwise,
+ // these regions would look empty and this will confuse parts of
+ // G1. For example, the code that looks for a consecutive number
+ // of empty regions will consider them empty and try to
+ // re-allocate them. We can extend is_empty() to also include
+ // !continuesHumongous(), but it is easier to just update the top
+ // fields here. The way we set top for all regions (i.e., top ==
+ // end for all regions but the last one, top == new_top for the
+ // last one) is actually used when we will free up the humongous
+ // region in free_humongous_region().
+ hr = NULL;
+ for (int i = first + 1; i < last; ++i) {
+ hr = _hrs->at(i);
+ if ((i + 1) == last) {
+ // last continues humongous region
+ assert(hr->bottom() < new_top && new_top <= hr->end(),
+ "new_top should fall on this region");
+ hr->set_top(new_top);
+ } else {
+ // not last one
+ assert(new_top > hr->end(), "new_top should be above this region");
+ hr->set_top(hr->end());
}
}
- }
- if (res != NULL) {
- // Increment by the number of regions allocated.
- // FIXME: Assumes regions all of size GrainBytes.
-#ifndef PRODUCT
- mr_bs()->verify_clean_region(MemRegion(res, res + num_regions *
- HeapRegion::GrainWords));
-#endif
- if (!eliminated_allocated_from_lists)
- remove_allocated_regions_from_lists();
- _summary_bytes_used += word_size * HeapWordSize;
- _free_regions -= num_regions;
- _num_humongous_regions += (int) num_regions;
- }
- assert(regions_accounted_for(), "Region Leakage");
- return res;
+ // If we have continues humongous regions (hr != NULL), then the
+ // end of the last one should match new_end and its top should
+ // match new_top.
+ assert(hr == NULL ||
+ (hr->end() == new_end && hr->top() == new_top), "sanity");
+
+ assert(first_hr->used() == word_size * HeapWordSize, "invariant");
+ _summary_bytes_used += first_hr->used();
+ _humongous_set.add(first_hr);
+
+ return new_obj;
+ }
+
+ verify_region_sets_optional();
+ return NULL;
}
void
G1CollectedHeap::retire_cur_alloc_region(HeapRegion* cur_alloc_region) {
- // The cleanup operation might update _summary_bytes_used
- // concurrently with this method. So, right now, if we don't wait
- // for it to complete, updates to _summary_bytes_used might get
- // lost. This will be resolved in the near future when the operation
- // of the free region list is revamped as part of CR 6977804.
- wait_for_cleanup_complete();
-
// Other threads might still be trying to allocate using CASes out
// of the region we are retiring, as they can do so without holding
// the Heap_lock. So we first have to make sure that noone else can
@@ -654,7 +800,7 @@
bool at_safepoint,
bool do_dirtying,
bool can_expand) {
- assert_heap_locked_or_at_safepoint();
+ assert_heap_locked_or_at_safepoint(true /* should_be_vm_thread */);
assert(_cur_alloc_region == NULL,
"replace_cur_alloc_region_and_allocate() should only be called "
"after retiring the previous current alloc region");
@@ -665,25 +811,12 @@
"we are not allowed to expand the young gen");
if (can_expand || !g1_policy()->is_young_list_full()) {
- if (!at_safepoint) {
- // The cleanup operation might update _summary_bytes_used
- // concurrently with this method. So, right now, if we don't
- // wait for it to complete, updates to _summary_bytes_used might
- // get lost. This will be resolved in the near future when the
- // operation of the free region list is revamped as part of
- // CR 6977804. If we're already at a safepoint, this call is
- // unnecessary, not to mention wrong.
- wait_for_cleanup_complete();
- }
-
- HeapRegion* new_cur_alloc_region = newAllocRegion(word_size,
- false /* zero_filled */);
+ HeapRegion* new_cur_alloc_region = new_alloc_region(word_size);
if (new_cur_alloc_region != NULL) {
assert(new_cur_alloc_region->is_empty(),
"the newly-allocated region should be empty, "
"as right now we only allocate new regions out of the free list");
g1_policy()->update_region_num(true /* next_is_young */);
- _summary_bytes_used -= new_cur_alloc_region->used();
set_region_short_lived_locked(new_cur_alloc_region);
assert(!new_cur_alloc_region->isHumongous(),
@@ -733,7 +866,7 @@
assert(_cur_alloc_region == NULL, "we failed to allocate a new current "
"alloc region, it should still be NULL");
- assert_heap_locked_or_at_safepoint();
+ assert_heap_locked_or_at_safepoint(true /* should_be_vm_thread */);
return NULL;
}
@@ -745,6 +878,10 @@
assert(!isHumongous(word_size), "attempt_allocation_slow() should not be "
"used for humongous allocations");
+ // We should only reach here when we were unable to allocate
+ // otherwise. So, we should have not active current alloc region.
+ assert(_cur_alloc_region == NULL, "current alloc region should be NULL");
+
// We will loop while succeeded is false, which means that we tried
// to do a collection, but the VM op did not succeed. So, when we
// exit the loop, either one of the allocation attempts was
@@ -756,30 +893,6 @@
// Every time we go round the loop we should be holding the Heap_lock.
assert_heap_locked();
- {
- // We may have concurrent cleanup working at the time. Wait for
- // it to complete. In the future we would probably want to make
- // the concurrent cleanup truly concurrent by decoupling it from
- // the allocation. This will happen in the near future as part
- // of CR 6977804 which will revamp the operation of the free
- // region list. The fact that wait_for_cleanup_complete() will
- // do a wait() means that we'll give up the Heap_lock. So, it's
- // possible that when we exit wait_for_cleanup_complete() we
- // might be able to allocate successfully (since somebody else
- // might have done a collection meanwhile). So, we'll attempt to
- // allocate again, just in case. When we make cleanup truly
- // concurrent with allocation, we should remove this allocation
- // attempt as it's redundant (we only reach here after an
- // allocation attempt has been unsuccessful).
- wait_for_cleanup_complete();
-
- HeapWord* result = attempt_allocation_locked(word_size);
- if (result != NULL) {
- assert_heap_not_locked();
- return result;
- }
- }
-
if (GC_locker::is_active_and_needs_gc()) {
// We are locked out of GC because of the GC locker. We can
// allocate a new region only if we can expand the young gen.
@@ -894,7 +1007,7 @@
// allocation paths that attempt to allocate a humongous object
// should eventually reach here. Currently, the only paths are from
// mem_allocate() and attempt_allocation_at_safepoint().
- assert_heap_locked_or_at_safepoint();
+ assert_heap_locked_or_at_safepoint(true /* should_be_vm_thread */);
assert(isHumongous(word_size), "attempt_allocation_humongous() "
"should only be used for humongous allocations");
assert(SafepointSynchronize::is_at_safepoint() == at_safepoint,
@@ -971,13 +1084,13 @@
}
}
- assert_heap_locked_or_at_safepoint();
+ assert_heap_locked_or_at_safepoint(true /* should_be_vm_thread */);
return NULL;
}
HeapWord* G1CollectedHeap::attempt_allocation_at_safepoint(size_t word_size,
bool expect_null_cur_alloc_region) {
- assert_at_safepoint();
+ assert_at_safepoint(true /* should_be_vm_thread */);
assert(_cur_alloc_region == NULL || !expect_null_cur_alloc_region,
err_msg("the current alloc region was unexpectedly found "
"to be non-NULL, cur alloc region: "PTR_FORMAT" "
@@ -1131,22 +1244,18 @@
}
void G1CollectedHeap::abandon_cur_alloc_region() {
- if (_cur_alloc_region != NULL) {
- // We're finished with the _cur_alloc_region.
- if (_cur_alloc_region->is_empty()) {
- _free_regions++;
- free_region(_cur_alloc_region);
- } else {
- // As we're builing (at least the young portion) of the collection
- // set incrementally we'll add the current allocation region to
- // the collection set here.
- if (_cur_alloc_region->is_young()) {
- g1_policy()->add_region_to_incremental_cset_lhs(_cur_alloc_region);
- }
- _summary_bytes_used += _cur_alloc_region->used();
- }
- _cur_alloc_region = NULL;
- }
+ assert_at_safepoint(true /* should_be_vm_thread */);
+
+ HeapRegion* cur_alloc_region = _cur_alloc_region;
+ if (cur_alloc_region != NULL) {
+ assert(!cur_alloc_region->is_empty(),
+ "the current alloc region can never be empty");
+ assert(cur_alloc_region->is_young(),
+ "the current alloc region should be young");
+
+ retire_cur_alloc_region_common(cur_alloc_region);
+ }
+ assert(_cur_alloc_region == NULL, "post-condition");
}
void G1CollectedHeap::abandon_gc_alloc_regions() {
@@ -1227,6 +1336,8 @@
bool G1CollectedHeap::do_collection(bool explicit_gc,
bool clear_all_soft_refs,
size_t word_size) {
+ assert_at_safepoint(true /* should_be_vm_thread */);
+
if (GC_locker::check_active_before_gc()) {
return false;
}
@@ -1238,8 +1349,7 @@
Universe::print_heap_before_gc();
}
- assert(SafepointSynchronize::is_at_safepoint(), "should be at safepoint");
- assert(Thread::current() == VMThread::vm_thread(), "should be in vm thread");
+ verify_region_sets_optional();
const bool do_clear_all_soft_refs = clear_all_soft_refs ||
collector_policy()->should_clear_all_soft_refs();
@@ -1262,6 +1372,9 @@
double start = os::elapsedTime();
g1_policy()->record_full_collection_start();
+ wait_while_free_regions_coming();
+ append_secondary_free_list_if_not_empty();
+
gc_prologue(true);
increment_total_collections(true /* full gc */);
@@ -1274,7 +1387,6 @@
gclog_or_tty->print(" VerifyBeforeGC:");
Universe::verify(true);
}
- assert(regions_accounted_for(), "Region leakage!");
COMPILER2_PRESENT(DerivedPointerTable::clear());
@@ -1298,7 +1410,6 @@
assert(_cur_alloc_region == NULL, "Invariant.");
g1_rem_set()->cleanupHRRS();
tear_down_region_lists();
- set_used_regions_to_need_zero_fill();
// We may have added regions to the current incremental collection
// set between the last GC or pause and now. We need to clear the
@@ -1333,9 +1444,7 @@
HandleMark hm; // Discard invalid handles created during gc
G1MarkSweep::invoke_at_safepoint(ref_processor(), do_clear_all_soft_refs);
}
- // Because freeing humongous regions may have added some unclean
- // regions, it is necessary to tear down again before rebuilding.
- tear_down_region_lists();
+ assert(free_regions() == 0, "we should not have added any free regions");
rebuild_region_lists();
_summary_bytes_used = recalculate_used();
@@ -1417,7 +1526,6 @@
JavaThread::dirty_card_queue_set().abandon_logs();
assert(!G1DeferredRSUpdate
|| (G1DeferredRSUpdate && (dirty_card_queue_set().completed_buffers_num() == 0)), "Should not be any");
- assert(regions_accounted_for(), "Region leakage!");
}
if (g1_policy()->in_young_gc_mode()) {
@@ -1431,6 +1539,8 @@
// Update the number of full collections that have been completed.
increment_full_collections_completed(false /* concurrent */);
+ verify_region_sets_optional();
+
if (PrintHeapAtGC) {
Universe::print_heap_after_gc();
}
@@ -1571,10 +1681,7 @@
HeapWord*
G1CollectedHeap::satisfy_failed_allocation(size_t word_size,
bool* succeeded) {
- assert(SafepointSynchronize::is_at_safepoint(),
- "satisfy_failed_allocation() should only be called at a safepoint");
- assert(Thread::current()->is_VM_thread(),
- "satisfy_failed_allocation() should only be called by the VM thread");
+ assert_at_safepoint(true /* should_be_vm_thread */);
*succeeded = true;
// Let's attempt the allocation first.
@@ -1646,53 +1753,22 @@
// allocated block, or else "NULL".
HeapWord* G1CollectedHeap::expand_and_allocate(size_t word_size) {
- assert(SafepointSynchronize::is_at_safepoint(),
- "expand_and_allocate() should only be called at a safepoint");
- assert(Thread::current()->is_VM_thread(),
- "expand_and_allocate() should only be called by the VM thread");
+ assert_at_safepoint(true /* should_be_vm_thread */);
+
+ verify_region_sets_optional();
size_t expand_bytes = word_size * HeapWordSize;
if (expand_bytes < MinHeapDeltaBytes) {
expand_bytes = MinHeapDeltaBytes;
}
expand(expand_bytes);
- assert(regions_accounted_for(), "Region leakage!");
+
+ verify_region_sets_optional();
return attempt_allocation_at_safepoint(word_size,
false /* expect_null_cur_alloc_region */);
}
-size_t G1CollectedHeap::free_region_if_totally_empty(HeapRegion* hr) {
- size_t pre_used = 0;
- size_t cleared_h_regions = 0;
- size_t freed_regions = 0;
- UncleanRegionList local_list;
- free_region_if_totally_empty_work(hr, pre_used, cleared_h_regions,
- freed_regions, &local_list);
-
- finish_free_region_work(pre_used, cleared_h_regions, freed_regions,
- &local_list);
- return pre_used;
-}
-
-void
-G1CollectedHeap::free_region_if_totally_empty_work(HeapRegion* hr,
- size_t& pre_used,
- size_t& cleared_h,
- size_t& freed_regions,
- UncleanRegionList* list,
- bool par) {
- assert(!hr->continuesHumongous(), "should have filtered these out");
- size_t res = 0;
- if (hr->used() > 0 && hr->garbage_bytes() == hr->used() &&
- !hr->is_young()) {
- if (G1PolicyVerbose > 0)
- gclog_or_tty->print_cr("Freeing empty region "PTR_FORMAT "(" SIZE_FORMAT " bytes)"
- " during cleanup", hr, hr->used());
- free_region_work(hr, pre_used, cleared_h, freed_regions, list, par);
- }
-}
-
// FIXME: both this and shrink could probably be more efficient by
// doing one "VirtualSpace::expand_by" call rather than several.
void G1CollectedHeap::expand(size_t expand_bytes) {
@@ -1725,19 +1801,7 @@
// Add it to the HeapRegionSeq.
_hrs->insert(hr);
- // Set the zero-fill state, according to whether it's already
- // zeroed.
- {
- MutexLockerEx x(ZF_mon, Mutex::_no_safepoint_check_flag);
- if (is_zeroed) {
- hr->set_zero_fill_complete();
- put_free_region_on_list_locked(hr);
- } else {
- hr->set_zero_fill_needed();
- put_region_on_unclean_list_locked(hr);
- }
- }
- _free_regions++;
+ _free_list.add_as_tail(hr);
// And we used up an expansion region to create it.
_expansion_regions--;
// Tell the cardtable about it.
@@ -1746,6 +1810,7 @@
_bot_shared->resize(_g1_committed.word_size());
}
}
+
if (Verbose && PrintGC) {
size_t new_mem_size = _g1_storage.committed_size();
gclog_or_tty->print_cr("Expanding garbage-first heap from %ldK by %ldK to %ldK",
@@ -1770,7 +1835,6 @@
assert(mr.start() == (HeapWord*)_g1_storage.high(), "Bad shrink!");
_g1_committed.set_end(mr.start());
- _free_regions -= num_regions_deleted;
_expansion_regions += num_regions_deleted;
// Tell the cardtable about it.
@@ -1790,10 +1854,17 @@
}
void G1CollectedHeap::shrink(size_t shrink_bytes) {
+ verify_region_sets_optional();
+
release_gc_alloc_regions(true /* totally */);
+ // Instead of tearing down / rebuilding the free lists here, we
+ // could instead use the remove_all_pending() method on free_list to
+ // remove only the ones that we need to remove.
tear_down_region_lists(); // We will rebuild them in a moment.
shrink_helper(shrink_bytes);
rebuild_region_lists();
+
+ verify_region_sets_optional();
}
// Public methods.
@@ -1812,18 +1883,17 @@
_ref_processor(NULL),
_process_strong_tasks(new SubTasksDone(G1H_PS_NumElements)),
_bot_shared(NULL),
- _par_alloc_during_gc_lock(Mutex::leaf, "par alloc during GC lock"),
_objs_with_preserved_marks(NULL), _preserved_marks_of_objs(NULL),
_evac_failure_scan_stack(NULL) ,
_mark_in_progress(false),
- _cg1r(NULL), _czft(NULL), _summary_bytes_used(0),
+ _cg1r(NULL), _summary_bytes_used(0),
_cur_alloc_region(NULL),
_refine_cte_cl(NULL),
- _free_region_list(NULL), _free_region_list_size(0),
- _free_regions(0),
_full_collection(false),
- _unclean_region_list(),
- _unclean_regions_coming(false),
+ _free_list("Master Free List"),
+ _secondary_free_list("Secondary Free List"),
+ _humongous_set("Master Humongous Set"),
+ _free_regions_coming(false),
_young_list(new YoungList(this)),
_gc_time_stamp(0),
_surviving_young_words(NULL),
@@ -1944,8 +2014,6 @@
_expansion_regions = max_byte_size/HeapRegion::GrainBytes;
- _num_humongous_regions = 0;
-
// Create the gen rem set (and barrier set) for the entire reserved region.
_rem_set = collector_policy()->create_rem_set(_reserved, 2);
set_barrier_set(rem_set()->bs());
@@ -1990,6 +2058,8 @@
guarantee((size_t) HeapRegion::CardsPerRegion < max_cards_per_region,
"too many cards per region");
+ HeapRegionSet::set_unrealistically_long_length(max_regions() + 1);
+
_bot_shared = new G1BlockOffsetSharedArray(_reserved,
heap_word_size(init_byte_size));
@@ -2014,11 +2084,6 @@
_cm = new ConcurrentMark(heap_rs, (int) max_regions());
_cmThread = _cm->cmThread();
- // ...and the concurrent zero-fill thread, if necessary.
- if (G1ConcZeroFill) {
- _czft = new ConcurrentZFThread();
- }
-
// Initialize the from_card cache structure of HeapRegionRemSet.
HeapRegionRemSet::init_heap(max_regions());
@@ -2192,7 +2257,7 @@
#endif // PRODUCT
size_t G1CollectedHeap::unsafe_max_alloc() {
- if (_free_regions > 0) return HeapRegion::GrainBytes;
+ if (free_regions() > 0) return HeapRegion::GrainBytes;
// otherwise, is there space in the current allocation region?
// We need to store the current allocation region in a local variable
@@ -2272,8 +2337,7 @@
}
void G1CollectedHeap::collect_as_vm_thread(GCCause::Cause cause) {
- assert(Thread::current()->is_VM_thread(), "Precondition#1");
- assert(Heap_lock->is_locked(), "Precondition#2");
+ assert_at_safepoint(true /* should_be_vm_thread */);
GCCauseSetter gcs(this, cause);
switch (cause) {
case GCCause::_heap_inspection:
@@ -2296,12 +2360,6 @@
{
MutexLocker ml(Heap_lock);
- // Don't want to do a GC until cleanup is completed. This
- // limitation will be removed in the near future when the
- // operation of the free region list is revamped as part of
- // CR 6977804.
- wait_for_cleanup_complete();
-
// Read the GC count while holding the Heap_lock
gc_count_before = SharedHeap::heap()->total_collections();
full_gc_count_before = SharedHeap::heap()->total_full_collections();
@@ -2680,10 +2738,6 @@
}
}
-bool G1CollectedHeap::allocs_are_zero_filled() {
- return false;
-}
-
size_t G1CollectedHeap::large_typearray_limit() {
// FIXME
return HeapRegion::GrainBytes/HeapWordSize;
@@ -2698,7 +2752,6 @@
return 0;
}
-
void G1CollectedHeap::prepare_for_verify() {
if (SafepointSynchronize::is_at_safepoint() || ! UseTLAB) {
ensure_parsability(false);
@@ -2909,7 +2962,9 @@
&rootsCl);
bool failures = rootsCl.failures();
rem_set()->invalidate(perm_gen()->used_region(), false);
- if (!silent) { gclog_or_tty->print("heapRegions "); }
+ if (!silent) { gclog_or_tty->print("HeapRegionSets "); }
+ verify_region_sets();
+ if (!silent) { gclog_or_tty->print("HeapRegions "); }
if (GCParallelVerificationEnabled && ParallelGCThreads > 1) {
assert(check_heap_region_claim_values(HeapRegion::InitialClaimValue),
"sanity check");
@@ -2937,7 +2992,7 @@
failures = true;
}
}
- if (!silent) gclog_or_tty->print("remset ");
+ if (!silent) gclog_or_tty->print("RemSet ");
rem_set()->verify();
if (failures) {
@@ -3008,15 +3063,10 @@
if (G1CollectedHeap::use_parallel_gc_threads()) {
workers()->print_worker_threads_on(st);
}
-
_cmThread->print_on(st);
st->cr();
-
_cm->print_worker_threads_on(st);
-
_cg1r->print_worker_threads_on(st);
-
- _czft->print_on(st);
st->cr();
}
@@ -3026,7 +3076,6 @@
}
tc->do_thread(_cmThread);
_cg1r->threads_do(tc);
- tc->do_thread(_czft);
}
void G1CollectedHeap::print_tracing_info() const {
@@ -3042,15 +3091,10 @@
if (G1SummarizeConcMark) {
concurrent_mark()->print_summary_info();
}
- if (G1SummarizeZFStats) {
- ConcurrentZFThread::print_summary_info();
- }
g1_policy()->print_yg_surv_rate_info();
-
SpecializationStats::print();
}
-
int G1CollectedHeap::addr_to_arena_id(void* addr) const {
HeapRegion* hr = heap_region_containing(addr);
if (hr == NULL) {
@@ -3249,6 +3293,9 @@
bool
G1CollectedHeap::do_collection_pause_at_safepoint(double target_pause_time_ms) {
+ assert_at_safepoint(true /* should_be_vm_thread */);
+ guarantee(!is_gc_active(), "collection is not reentrant");
+
if (GC_locker::check_active_before_gc()) {
return false;
}
@@ -3260,6 +3307,8 @@
Universe::print_heap_before_gc();
}
+ verify_region_sets_optional();
+
{
// This call will decide whether this pause is an initial-mark
// pause. If it is, during_initial_mark_pause() will return true
@@ -3290,10 +3339,16 @@
TraceMemoryManagerStats tms(false /* fullGC */);
- assert(SafepointSynchronize::is_at_safepoint(), "should be at safepoint");
- assert(Thread::current() == VMThread::vm_thread(), "should be in vm thread");
- guarantee(!is_gc_active(), "collection is not reentrant");
- assert(regions_accounted_for(), "Region leakage!");
+ // If there are any free regions available on the secondary_free_list
+ // make sure we append them to the free_list. However, we don't
+ // have to wait for the rest of the cleanup operation to
+ // finish. If it's still going on that's OK. If we run out of
+ // regions, the region allocation code will check the
+ // secondary_free_list and potentially wait if more free regions
+ // are coming (see new_region_try_secondary_free_list()).
+ if (!G1StressConcRegionFreeing) {
+ append_secondary_free_list_if_not_empty();
+ }
increment_gc_time_stamp();
@@ -3373,8 +3428,6 @@
// progress, this will be zero.
_cm->set_oops_do_bound();
- assert(regions_accounted_for(), "Region leakage.");
-
if (mark_in_progress())
concurrent_mark()->newCSet();
@@ -3470,8 +3523,6 @@
g1_policy()->record_pause_time_ms(pause_time_ms);
g1_policy()->record_collection_pause_end();
- assert(regions_accounted_for(), "Region leakage.");
-
MemoryService::track_memory_usage();
if (VerifyAfterGC && total_collections() >= VerifyGCStartAt) {
@@ -3502,8 +3553,6 @@
gc_epilogue(false);
}
- assert(verify_region_lists(), "Bad region lists.");
-
if (ExitAfterGCNum > 0 && total_collections() == ExitAfterGCNum) {
gclog_or_tty->print_cr("Stopping after GC #%d", ExitAfterGCNum);
print_tracing_info();
@@ -3511,6 +3560,8 @@
}
}
+ verify_region_sets_optional();
+
TASKQUEUE_STATS_ONLY(if (ParallelGCVerbose) print_taskqueue_stats());
TASKQUEUE_STATS_ONLY(reset_taskqueue_stats());
@@ -3617,7 +3668,7 @@
void G1CollectedHeap::push_gc_alloc_region(HeapRegion* hr) {
assert(Thread::current()->is_VM_thread() ||
- par_alloc_during_gc_lock()->owned_by_self(), "Precondition");
+ FreeList_lock->owned_by_self(), "Precondition");
assert(!hr->is_gc_alloc_region() && !hr->in_collection_set(),
"Precondition.");
hr->set_is_gc_alloc_region(true);
@@ -3639,7 +3690,7 @@
#endif // G1_DEBUG
void G1CollectedHeap::forget_alloc_region_list() {
- assert(Thread::current()->is_VM_thread(), "Precondition");
+ assert_at_safepoint(true /* should_be_vm_thread */);
while (_gc_alloc_region_list != NULL) {
HeapRegion* r = _gc_alloc_region_list;
assert(r->is_gc_alloc_region(), "Invariant.");
@@ -3659,9 +3710,6 @@
_young_list->add_survivor_region(r);
}
}
- if (r->is_empty()) {
- ++_free_regions;
- }
}
#ifdef G1_DEBUG
FindGCAllocRegion fa;
@@ -3714,7 +3762,7 @@
if (alloc_region == NULL) {
// we will get a new GC alloc region
- alloc_region = newAllocRegionWithExpansion(ap, 0);
+ alloc_region = new_gc_alloc_region(ap, 0);
} else {
// the region was retained from the last collection
++_gc_alloc_region_counts[ap];
@@ -3769,11 +3817,9 @@
set_gc_alloc_region(ap, NULL);
if (r->is_empty()) {
- // we didn't actually allocate anything in it; let's just put
- // it on the free list
- MutexLockerEx x(ZF_mon, Mutex::_no_safepoint_check_flag);
- r->set_zero_fill_complete();
- put_free_region_on_list_locked(r);
+ // We didn't actually allocate anything in it; let's just put
+ // it back on the free list.
+ _free_list.add_as_tail(r);
} else if (_retain_gc_alloc_region[ap] && !totally) {
// retain it so that we can use it at the beginning of the next GC
_retained_gc_alloc_regions[ap] = r;
@@ -4128,8 +4174,6 @@
HeapWord* block = alloc_region->par_allocate(word_size);
if (block == NULL) {
- MutexLockerEx x(par_alloc_during_gc_lock(),
- Mutex::_no_safepoint_check_flag);
block = allocate_during_gc_slow(purpose, alloc_region, true, word_size);
}
return block;
@@ -4158,6 +4202,12 @@
err_msg("we should not be seeing humongous allocation requests "
"during GC, word_size = "SIZE_FORMAT, word_size));
+ // We need to make sure we serialize calls to this method. Given
+ // that the FreeList_lock guards accesses to the free_list anyway,
+ // and we need to potentially remove a region from it, we'll use it
+ // to protect the whole call.
+ MutexLockerEx x(FreeList_lock, Mutex::_no_safepoint_check_flag);
+
HeapWord* block = NULL;
// In the parallel case, a previous thread to obtain the lock may have
// already assigned a new gc_alloc_region.
@@ -4203,7 +4253,7 @@
}
// Now allocate a new region for allocation.
- alloc_region = newAllocRegionWithExpansion(purpose, word_size, false /*zero_filled*/);
+ alloc_region = new_gc_alloc_region(purpose, word_size);
// let the caller handle alloc failure
if (alloc_region != NULL) {
@@ -4211,9 +4261,6 @@
assert(check_gc_alloc_regions(), "alloc regions messed up");
assert(alloc_region->saved_mark_at_top(),
"Mark should have been saved already.");
- // We used to assert that the region was zero-filled here, but no
- // longer.
-
// This must be done last: once it's installed, other regions may
// allocate in it (without holding the lock.)
set_gc_alloc_region(purpose, alloc_region);
@@ -4878,91 +4925,91 @@
COMPILER2_PRESENT(DerivedPointerTable::update_pointers());
}
-void G1CollectedHeap::free_region(HeapRegion* hr) {
- size_t pre_used = 0;
- size_t cleared_h_regions = 0;
- size_t freed_regions = 0;
- UncleanRegionList local_list;
-
- HeapWord* start = hr->bottom();
- HeapWord* end = hr->prev_top_at_mark_start();
- size_t used_bytes = hr->used();
- size_t live_bytes = hr->max_live_bytes();
- if (used_bytes > 0) {
- guarantee( live_bytes <= used_bytes, "invariant" );
- } else {
- guarantee( live_bytes == 0, "invariant" );
- }
-
- size_t garbage_bytes = used_bytes - live_bytes;
- if (garbage_bytes > 0)
- g1_policy()->decrease_known_garbage_bytes(garbage_bytes);
-
- free_region_work(hr, pre_used, cleared_h_regions, freed_regions,
- &local_list);
- finish_free_region_work(pre_used, cleared_h_regions, freed_regions,
- &local_list);
-}
-
-void
-G1CollectedHeap::free_region_work(HeapRegion* hr,
- size_t& pre_used,
- size_t& cleared_h_regions,
- size_t& freed_regions,
- UncleanRegionList* list,
- bool par) {
- pre_used += hr->used();
- if (hr->isHumongous()) {
- assert(hr->startsHumongous(),
- "Only the start of a humongous region should be freed.");
- int ind = _hrs->find(hr);
- assert(ind != -1, "Should have an index.");
- // Clear the start region.
- hr->hr_clear(par, true /*clear_space*/);
- list->insert_before_head(hr);
- cleared_h_regions++;
- freed_regions++;
- // Clear any continued regions.
- ind++;
- while ((size_t)ind < n_regions()) {
- HeapRegion* hrc = _hrs->at(ind);
- if (!hrc->continuesHumongous()) break;
- // Otherwise, does continue the H region.
- assert(hrc->humongous_start_region() == hr, "Huh?");
- hrc->hr_clear(par, true /*clear_space*/);
- cleared_h_regions++;
- freed_regions++;
- list->insert_before_head(hrc);
- ind++;
+void G1CollectedHeap::free_region_if_totally_empty(HeapRegion* hr,
+ size_t* pre_used,
+ FreeRegionList* free_list,
+ HumongousRegionSet* humongous_proxy_set,
+ bool par) {
+ if (hr->used() > 0 && hr->max_live_bytes() == 0 && !hr->is_young()) {
+ if (hr->isHumongous()) {
+ assert(hr->startsHumongous(), "we should only see starts humongous");
+ free_humongous_region(hr, pre_used, free_list, humongous_proxy_set, par);
+ } else {
+ free_region(hr, pre_used, free_list, par);
}
- } else {
- hr->hr_clear(par, true /*clear_space*/);
- list->insert_before_head(hr);
- freed_regions++;
- // If we're using clear2, this should not be enabled.
- // assert(!hr->in_cohort(), "Can't be both free and in a cohort.");
}
}
-void G1CollectedHeap::finish_free_region_work(size_t pre_used,
- size_t cleared_h_regions,
- size_t freed_regions,
- UncleanRegionList* list) {
- if (list != NULL && list->sz() > 0) {
- prepend_region_list_on_unclean_list(list);
- }
- // Acquire a lock, if we're parallel, to update possibly-shared
- // variables.
- Mutex* lock = (n_par_threads() > 0) ? ParGCRareEvent_lock : NULL;
- {
+void G1CollectedHeap::free_region(HeapRegion* hr,
+ size_t* pre_used,
+ FreeRegionList* free_list,
+ bool par) {
+ assert(!hr->isHumongous(), "this is only for non-humongous regions");
+ assert(!hr->is_empty(), "the region should not be empty");
+ assert(free_list != NULL, "pre-condition");
+
+ *pre_used += hr->used();
+ hr->hr_clear(par, true /* clear_space */);
+ free_list->add_as_tail(hr);
+}
+
+void G1CollectedHeap::free_humongous_region(HeapRegion* hr,
+ size_t* pre_used,
+ FreeRegionList* free_list,
+ HumongousRegionSet* humongous_proxy_set,
+ bool par) {
+ assert(hr->startsHumongous(), "this is only for starts humongous regions");
+ assert(free_list != NULL, "pre-condition");
+ assert(humongous_proxy_set != NULL, "pre-condition");
+
+ size_t hr_used = hr->used();
+ size_t hr_capacity = hr->capacity();
+ size_t hr_pre_used = 0;
+ _humongous_set.remove_with_proxy(hr, humongous_proxy_set);
+ hr->set_notHumongous();
+ free_region(hr, &hr_pre_used, free_list, par);
+
+ int i = hr->hrs_index() + 1;
+ size_t num = 1;
+ while ((size_t) i < n_regions()) {
+ HeapRegion* curr_hr = _hrs->at(i);
+ if (!curr_hr->continuesHumongous()) {
+ break;
+ }
+ curr_hr->set_notHumongous();
+ free_region(curr_hr, &hr_pre_used, free_list, par);
+ num += 1;
+ i += 1;
+ }
+ assert(hr_pre_used == hr_used,
+ err_msg("hr_pre_used: "SIZE_FORMAT" and hr_used: "SIZE_FORMAT" "
+ "should be the same", hr_pre_used, hr_used));
+ *pre_used += hr_pre_used;
+}
+
+void G1CollectedHeap::update_sets_after_freeing_regions(size_t pre_used,
+ FreeRegionList* free_list,
+ HumongousRegionSet* humongous_proxy_set,
+ bool par) {
+ if (pre_used > 0) {
+ Mutex* lock = (par) ? ParGCRareEvent_lock : NULL;
MutexLockerEx x(lock, Mutex::_no_safepoint_check_flag);
+ assert(_summary_bytes_used >= pre_used,
+ err_msg("invariant: _summary_bytes_used: "SIZE_FORMAT" "
+ "should be >= pre_used: "SIZE_FORMAT,
+ _summary_bytes_used, pre_used));
_summary_bytes_used -= pre_used;
- _num_humongous_regions -= (int) cleared_h_regions;
- _free_regions += freed_regions;
+ }
+ if (free_list != NULL && !free_list->is_empty()) {
+ MutexLockerEx x(FreeList_lock, Mutex::_no_safepoint_check_flag);
+ _free_list.add_as_tail(free_list);
+ }
+ if (humongous_proxy_set != NULL && !humongous_proxy_set->is_empty()) {
+ MutexLockerEx x(OldSets_lock, Mutex::_no_safepoint_check_flag);
+ _humongous_set.update_from_proxy(humongous_proxy_set);
}
}
-
void G1CollectedHeap::dirtyCardsForYoungRegions(CardTableModRefBS* ct_bs, HeapRegion* list) {
while (list != NULL) {
guarantee( list->is_young(), "invariant" );
@@ -5085,6 +5132,9 @@
}
void G1CollectedHeap::free_collection_set(HeapRegion* cs_head) {
+ size_t pre_used = 0;
+ FreeRegionList local_free_list("Local List for CSet Freeing");
+
double young_time_ms = 0.0;
double non_young_time_ms = 0.0;
@@ -5103,6 +5153,8 @@
size_t rs_lengths = 0;
while (cur != NULL) {
+ assert(!is_on_free_list(cur), "sanity");
+
if (non_young) {
if (cur->is_young()) {
double end_sec = os::elapsedTime();
@@ -5113,14 +5165,12 @@
non_young = false;
}
} else {
- if (!cur->is_on_free_list()) {
- double end_sec = os::elapsedTime();
- double elapsed_ms = (end_sec - start_sec) * 1000.0;
- young_time_ms += elapsed_ms;
-
- start_sec = os::elapsedTime();
- non_young = true;
- }
+ double end_sec = os::elapsedTime();
+ double elapsed_ms = (end_sec - start_sec) * 1000.0;
+ young_time_ms += elapsed_ms;
+
+ start_sec = os::elapsedTime();
+ non_young = true;
}
rs_lengths += cur->rem_set()->occupied();
@@ -5153,9 +5203,8 @@
if (!cur->evacuation_failed()) {
// And the region is empty.
- assert(!cur->is_empty(),
- "Should not have empty regions in a CS.");
- free_region(cur);
+ assert(!cur->is_empty(), "Should not have empty regions in a CS.");
+ free_region(cur, &pre_used, &local_free_list, false /* par */);
} else {
cur->uninstall_surv_rate_group();
if (cur->is_young())
@@ -5176,6 +5225,9 @@
else
young_time_ms += elapsed_ms;
+ update_sets_after_freeing_regions(pre_used, &local_free_list,
+ NULL /* humongous_proxy_set */,
+ false /* par */);
policy->record_young_free_cset_time_ms(young_time_ms);
policy->record_non_young_free_cset_time_ms(non_young_time_ms);
}
@@ -5201,291 +5253,53 @@
}
}
-HeapRegion*
-G1CollectedHeap::alloc_region_from_unclean_list_locked(bool zero_filled) {
- assert(ZF_mon->owned_by_self(), "Precondition");
- HeapRegion* res = pop_unclean_region_list_locked();
- if (res != NULL) {
- assert(!res->continuesHumongous() &&
- res->zero_fill_state() != HeapRegion::Allocated,
- "Only free regions on unclean list.");
- if (zero_filled) {
- res->ensure_zero_filled_locked();
- res->set_zero_fill_allocated();
- }
- }
- return res;
-}
-
-HeapRegion* G1CollectedHeap::alloc_region_from_unclean_list(bool zero_filled) {
- MutexLockerEx zx(ZF_mon, Mutex::_no_safepoint_check_flag);
- return alloc_region_from_unclean_list_locked(zero_filled);
+void G1CollectedHeap::set_free_regions_coming() {
+ if (G1ConcRegionFreeingVerbose) {
+ gclog_or_tty->print_cr("G1ConcRegionFreeing [cm thread] : "
+ "setting free regions coming");
+ }
+
+ assert(!free_regions_coming(), "pre-condition");
+ _free_regions_coming = true;
}
-void G1CollectedHeap::put_region_on_unclean_list(HeapRegion* r) {
- MutexLockerEx x(ZF_mon, Mutex::_no_safepoint_check_flag);
- put_region_on_unclean_list_locked(r);
- if (should_zf()) ZF_mon->notify_all(); // Wake up ZF thread.
-}
-
-void G1CollectedHeap::set_unclean_regions_coming(bool b) {
- MutexLockerEx x(Cleanup_mon);
- set_unclean_regions_coming_locked(b);
-}
-
-void G1CollectedHeap::set_unclean_regions_coming_locked(bool b) {
- assert(Cleanup_mon->owned_by_self(), "Precondition");
- _unclean_regions_coming = b;
- // Wake up mutator threads that might be waiting for completeCleanup to
- // finish.
- if (!b) Cleanup_mon->notify_all();
-}
-
-void G1CollectedHeap::wait_for_cleanup_complete() {
- assert_not_at_safepoint();
- MutexLockerEx x(Cleanup_mon);
- wait_for_cleanup_complete_locked();
-}
-
-void G1CollectedHeap::wait_for_cleanup_complete_locked() {
- assert(Cleanup_mon->owned_by_self(), "precondition");
- while (_unclean_regions_coming) {
- Cleanup_mon->wait();
+void G1CollectedHeap::reset_free_regions_coming() {
+ {
+ assert(free_regions_coming(), "pre-condition");
+ MutexLockerEx x(SecondaryFreeList_lock, Mutex::_no_safepoint_check_flag);
+ _free_regions_coming = false;
+ SecondaryFreeList_lock->notify_all();
+ }
+
+ if (G1ConcRegionFreeingVerbose) {
+ gclog_or_tty->print_cr("G1ConcRegionFreeing [cm thread] : "
+ "reset free regions coming");
}
}
-void
-G1CollectedHeap::put_region_on_unclean_list_locked(HeapRegion* r) {
- assert(ZF_mon->owned_by_self(), "precondition.");
-#ifdef ASSERT
- if (r->is_gc_alloc_region()) {
- ResourceMark rm;
- stringStream region_str;
- print_on(®ion_str);
- assert(!r->is_gc_alloc_region(), err_msg("Unexpected GC allocation region: %s",
- region_str.as_string()));
- }
-#endif
- _unclean_region_list.insert_before_head(r);
-}
-
-void
-G1CollectedHeap::prepend_region_list_on_unclean_list(UncleanRegionList* list) {
- MutexLockerEx x(ZF_mon, Mutex::_no_safepoint_check_flag);
- prepend_region_list_on_unclean_list_locked(list);
- if (should_zf()) ZF_mon->notify_all(); // Wake up ZF thread.
-}
-
-void
-G1CollectedHeap::
-prepend_region_list_on_unclean_list_locked(UncleanRegionList* list) {
- assert(ZF_mon->owned_by_self(), "precondition.");
- _unclean_region_list.prepend_list(list);
-}
-
-HeapRegion* G1CollectedHeap::pop_unclean_region_list_locked() {
- assert(ZF_mon->owned_by_self(), "precondition.");
- HeapRegion* res = _unclean_region_list.pop();
- if (res != NULL) {
- // Inform ZF thread that there's a new unclean head.
- if (_unclean_region_list.hd() != NULL && should_zf())
- ZF_mon->notify_all();
- }
- return res;
-}
-
-HeapRegion* G1CollectedHeap::peek_unclean_region_list_locked() {
- assert(ZF_mon->owned_by_self(), "precondition.");
- return _unclean_region_list.hd();
-}
-
-
-bool G1CollectedHeap::move_cleaned_region_to_free_list_locked() {
- assert(ZF_mon->owned_by_self(), "Precondition");
- HeapRegion* r = peek_unclean_region_list_locked();
- if (r != NULL && r->zero_fill_state() == HeapRegion::ZeroFilled) {
- // Result of below must be equal to "r", since we hold the lock.
- (void)pop_unclean_region_list_locked();
- put_free_region_on_list_locked(r);
- return true;
- } else {
- return false;
- }
-}
-
-bool G1CollectedHeap::move_cleaned_region_to_free_list() {
- MutexLockerEx x(ZF_mon, Mutex::_no_safepoint_check_flag);
- return move_cleaned_region_to_free_list_locked();
-}
-
-
-void G1CollectedHeap::put_free_region_on_list_locked(HeapRegion* r) {
- assert(ZF_mon->owned_by_self(), "precondition.");
- assert(_free_region_list_size == free_region_list_length(), "Inv");
- assert(r->zero_fill_state() == HeapRegion::ZeroFilled,
- "Regions on free list must be zero filled");
- assert(!r->isHumongous(), "Must not be humongous.");
- assert(r->is_empty(), "Better be empty");
- assert(!r->is_on_free_list(),
- "Better not already be on free list");
- assert(!r->is_on_unclean_list(),
- "Better not already be on unclean list");
- r->set_on_free_list(true);
- r->set_next_on_free_list(_free_region_list);
- _free_region_list = r;
- _free_region_list_size++;
- assert(_free_region_list_size == free_region_list_length(), "Inv");
-}
-
-void G1CollectedHeap::put_free_region_on_list(HeapRegion* r) {
- MutexLockerEx x(ZF_mon, Mutex::_no_safepoint_check_flag);
- put_free_region_on_list_locked(r);
-}
-
-HeapRegion* G1CollectedHeap::pop_free_region_list_locked() {
- assert(ZF_mon->owned_by_self(), "precondition.");
- assert(_free_region_list_size == free_region_list_length(), "Inv");
- HeapRegion* res = _free_region_list;
- if (res != NULL) {
- _free_region_list = res->next_from_free_list();
- _free_region_list_size--;
- res->set_on_free_list(false);
- res->set_next_on_free_list(NULL);
- assert(_free_region_list_size == free_region_list_length(), "Inv");
- }
- return res;
-}
-
-
-HeapRegion* G1CollectedHeap::alloc_free_region_from_lists(bool zero_filled) {
- // By self, or on behalf of self.
- assert(Heap_lock->is_locked(), "Precondition");
- HeapRegion* res = NULL;
- bool first = true;
- while (res == NULL) {
- if (zero_filled || !first) {
- MutexLockerEx x(ZF_mon, Mutex::_no_safepoint_check_flag);
- res = pop_free_region_list_locked();
- if (res != NULL) {
- assert(!res->zero_fill_is_allocated(),
- "No allocated regions on free list.");
- res->set_zero_fill_allocated();
- } else if (!first) {
- break; // We tried both, time to return NULL.
- }
- }
-
- if (res == NULL) {
- res = alloc_region_from_unclean_list(zero_filled);
- }
- assert(res == NULL ||
- !zero_filled ||
- res->zero_fill_is_allocated(),
- "We must have allocated the region we're returning");
- first = false;
- }
- return res;
-}
-
-void G1CollectedHeap::remove_allocated_regions_from_lists() {
- MutexLockerEx x(ZF_mon, Mutex::_no_safepoint_check_flag);
- {
- HeapRegion* prev = NULL;
- HeapRegion* cur = _unclean_region_list.hd();
- while (cur != NULL) {
- HeapRegion* next = cur->next_from_unclean_list();
- if (cur->zero_fill_is_allocated()) {
- // Remove from the list.
- if (prev == NULL) {
- (void)_unclean_region_list.pop();
- } else {
- _unclean_region_list.delete_after(prev);
- }
- cur->set_on_unclean_list(false);
- cur->set_next_on_unclean_list(NULL);
- } else {
- prev = cur;
- }
- cur = next;
- }
- assert(_unclean_region_list.sz() == unclean_region_list_length(),
- "Inv");
+void G1CollectedHeap::wait_while_free_regions_coming() {
+ // Most of the time we won't have to wait, so let's do a quick test
+ // first before we take the lock.
+ if (!free_regions_coming()) {
+ return;
+ }
+
+ if (G1ConcRegionFreeingVerbose) {
+ gclog_or_tty->print_cr("G1ConcRegionFreeing [other] : "
+ "waiting for free regions");
}
{
- HeapRegion* prev = NULL;
- HeapRegion* cur = _free_region_list;
- while (cur != NULL) {
- HeapRegion* next = cur->next_from_free_list();
- if (cur->zero_fill_is_allocated()) {
- // Remove from the list.
- if (prev == NULL) {
- _free_region_list = cur->next_from_free_list();
- } else {
- prev->set_next_on_free_list(cur->next_from_free_list());
- }
- cur->set_on_free_list(false);
- cur->set_next_on_free_list(NULL);
- _free_region_list_size--;
- } else {
- prev = cur;
- }
- cur = next;
+ MutexLockerEx x(SecondaryFreeList_lock, Mutex::_no_safepoint_check_flag);
+ while (free_regions_coming()) {
+ SecondaryFreeList_lock->wait(Mutex::_no_safepoint_check_flag);
}
- assert(_free_region_list_size == free_region_list_length(), "Inv");
- }
-}
-
-bool G1CollectedHeap::verify_region_lists() {
- MutexLockerEx x(ZF_mon, Mutex::_no_safepoint_check_flag);
- return verify_region_lists_locked();
-}
-
-bool G1CollectedHeap::verify_region_lists_locked() {
- HeapRegion* unclean = _unclean_region_list.hd();
- while (unclean != NULL) {
- guarantee(unclean->is_on_unclean_list(), "Well, it is!");
- guarantee(!unclean->is_on_free_list(), "Well, it shouldn't be!");
- guarantee(unclean->zero_fill_state() != HeapRegion::Allocated,
- "Everything else is possible.");
- unclean = unclean->next_from_unclean_list();
- }
- guarantee(_unclean_region_list.sz() == unclean_region_list_length(), "Inv");
-
- HeapRegion* free_r = _free_region_list;
- while (free_r != NULL) {
- assert(free_r->is_on_free_list(), "Well, it is!");
- assert(!free_r->is_on_unclean_list(), "Well, it shouldn't be!");
- switch (free_r->zero_fill_state()) {
- case HeapRegion::NotZeroFilled:
- case HeapRegion::ZeroFilling:
- guarantee(false, "Should not be on free list.");
- break;
- default:
- // Everything else is possible.
- break;
- }
- free_r = free_r->next_from_free_list();
- }
- guarantee(_free_region_list_size == free_region_list_length(), "Inv");
- // If we didn't do an assertion...
- return true;
-}
-
-size_t G1CollectedHeap::free_region_list_length() {
- assert(ZF_mon->owned_by_self(), "precondition.");
- size_t len = 0;
- HeapRegion* cur = _free_region_list;
- while (cur != NULL) {
- len++;
- cur = cur->next_from_free_list();
- }
- return len;
-}
-
-size_t G1CollectedHeap::unclean_region_list_length() {
- assert(ZF_mon->owned_by_self(), "precondition.");
- return _unclean_region_list.length();
+ }
+
+ if (G1ConcRegionFreeingVerbose) {
+ gclog_or_tty->print_cr("G1ConcRegionFreeing [other] : "
+ "done waiting for free regions");
+ }
}
size_t G1CollectedHeap::n_regions() {
@@ -5498,55 +5312,6 @@
HeapRegion::GrainBytes;
}
-size_t G1CollectedHeap::free_regions() {
- /* Possibly-expensive assert.
- assert(_free_regions == count_free_regions(),
- "_free_regions is off.");
- */
- return _free_regions;
-}
-
-bool G1CollectedHeap::should_zf() {
- return _free_region_list_size < (size_t) G1ConcZFMaxRegions;
-}
-
-class RegionCounter: public HeapRegionClosure {
- size_t _n;
-public:
- RegionCounter() : _n(0) {}
- bool doHeapRegion(HeapRegion* r) {
- if (r->is_empty()) {
- assert(!r->isHumongous(), "H regions should not be empty.");
- _n++;
- }
- return false;
- }
- int res() { return (int) _n; }
-};
-
-size_t G1CollectedHeap::count_free_regions() {
- RegionCounter rc;
- heap_region_iterate(&rc);
- size_t n = rc.res();
- if (_cur_alloc_region != NULL && _cur_alloc_region->is_empty())
- n--;
- return n;
-}
-
-size_t G1CollectedHeap::count_free_regions_list() {
- size_t n = 0;
- size_t o = 0;
- ZF_mon->lock_without_safepoint_check();
- HeapRegion* cur = _free_region_list;
- while (cur != NULL) {
- cur = cur->next_from_free_list();
- n++;
- }
- size_t m = unclean_region_list_length();
- ZF_mon->unlock();
- return n + m;
-}
-
void G1CollectedHeap::set_region_short_lived_locked(HeapRegion* hr) {
assert(heap_lock_held_for_gc(),
"the heap lock should already be held by or for this thread");
@@ -5618,28 +5383,19 @@
}
}
-
// Done at the start of full GC.
void G1CollectedHeap::tear_down_region_lists() {
- MutexLockerEx x(ZF_mon, Mutex::_no_safepoint_check_flag);
- while (pop_unclean_region_list_locked() != NULL) ;
- assert(_unclean_region_list.hd() == NULL && _unclean_region_list.sz() == 0,
- "Postconditions of loop.");
- while (pop_free_region_list_locked() != NULL) ;
- assert(_free_region_list == NULL, "Postcondition of loop.");
- if (_free_region_list_size != 0) {
- gclog_or_tty->print_cr("Size is %d.", _free_region_list_size);
- print_on(gclog_or_tty, true /* extended */);
- }
- assert(_free_region_list_size == 0, "Postconditions of loop.");
+ _free_list.remove_all();
}
-
class RegionResetter: public HeapRegionClosure {
- G1CollectedHeap* _g1;
- int _n;
+ G1CollectedHeap* _g1h;
+ FreeRegionList _local_free_list;
+
public:
- RegionResetter() : _g1(G1CollectedHeap::heap()), _n(0) {}
+ RegionResetter() : _g1h(G1CollectedHeap::heap()),
+ _local_free_list("Local Free List for RegionResetter") { }
+
bool doHeapRegion(HeapRegion* r) {
if (r->continuesHumongous()) return false;
if (r->top() > r->bottom()) {
@@ -5647,152 +5403,32 @@
Copy::fill_to_words(r->top(),
pointer_delta(r->end(), r->top()));
}
- r->set_zero_fill_allocated();
} else {
assert(r->is_empty(), "tautology");
- _n++;
- switch (r->zero_fill_state()) {
- case HeapRegion::NotZeroFilled:
- case HeapRegion::ZeroFilling:
- _g1->put_region_on_unclean_list_locked(r);
- break;
- case HeapRegion::Allocated:
- r->set_zero_fill_complete();
- // no break; go on to put on free list.
- case HeapRegion::ZeroFilled:
- _g1->put_free_region_on_list_locked(r);
- break;
- }
+ _local_free_list.add_as_tail(r);
}
return false;
}
- int getFreeRegionCount() {return _n;}
+ void update_free_lists() {
+ _g1h->update_sets_after_freeing_regions(0, &_local_free_list, NULL,
+ false /* par */);
+ }
};
// Done at the end of full GC.
void G1CollectedHeap::rebuild_region_lists() {
- MutexLockerEx x(ZF_mon, Mutex::_no_safepoint_check_flag);
// This needs to go at the end of the full GC.
RegionResetter rs;
heap_region_iterate(&rs);
- _free_regions = rs.getFreeRegionCount();
- // Tell the ZF thread it may have work to do.
- if (should_zf()) ZF_mon->notify_all();
-}
-
-class UsedRegionsNeedZeroFillSetter: public HeapRegionClosure {
- G1CollectedHeap* _g1;
- int _n;
-public:
- UsedRegionsNeedZeroFillSetter() : _g1(G1CollectedHeap::heap()), _n(0) {}
- bool doHeapRegion(HeapRegion* r) {
- if (r->continuesHumongous()) return false;
- if (r->top() > r->bottom()) {
- // There are assertions in "set_zero_fill_needed()" below that
- // require top() == bottom(), so this is technically illegal.
- // We'll skirt the law here, by making that true temporarily.
- DEBUG_ONLY(HeapWord* save_top = r->top();
- r->set_top(r->bottom()));
- r->set_zero_fill_needed();
- DEBUG_ONLY(r->set_top(save_top));
- }
- return false;
- }
-};
-
-// Done at the start of full GC.
-void G1CollectedHeap::set_used_regions_to_need_zero_fill() {
- MutexLockerEx x(ZF_mon, Mutex::_no_safepoint_check_flag);
- // This needs to go at the end of the full GC.
- UsedRegionsNeedZeroFillSetter rs;
- heap_region_iterate(&rs);
+ rs.update_free_lists();
}
void G1CollectedHeap::set_refine_cte_cl_concurrency(bool concurrent) {
_refine_cte_cl->set_concurrent(concurrent);
}
-#ifndef PRODUCT
-
-class PrintHeapRegionClosure: public HeapRegionClosure {
-public:
- bool doHeapRegion(HeapRegion *r) {
- gclog_or_tty->print("Region: "PTR_FORMAT":", r);
- if (r != NULL) {
- if (r->is_on_free_list())
- gclog_or_tty->print("Free ");
- if (r->is_young())
- gclog_or_tty->print("Young ");
- if (r->isHumongous())
- gclog_or_tty->print("Is Humongous ");
- r->print();
- }
- return false;
- }
-};
-
-class SortHeapRegionClosure : public HeapRegionClosure {
- size_t young_regions,free_regions, unclean_regions;
- size_t hum_regions, count;
- size_t unaccounted, cur_unclean, cur_alloc;
- size_t total_free;
- HeapRegion* cur;
-public:
- SortHeapRegionClosure(HeapRegion *_cur) : cur(_cur), young_regions(0),
- free_regions(0), unclean_regions(0),
- hum_regions(0),
- count(0), unaccounted(0),
- cur_alloc(0), total_free(0)
- {}
- bool doHeapRegion(HeapRegion *r) {
- count++;
- if (r->is_on_free_list()) free_regions++;
- else if (r->is_on_unclean_list()) unclean_regions++;
- else if (r->isHumongous()) hum_regions++;
- else if (r->is_young()) young_regions++;
- else if (r == cur) cur_alloc++;
- else unaccounted++;
- return false;
- }
- void print() {
- total_free = free_regions + unclean_regions;
- gclog_or_tty->print("%d regions\n", count);
- gclog_or_tty->print("%d free: free_list = %d unclean = %d\n",
- total_free, free_regions, unclean_regions);
- gclog_or_tty->print("%d humongous %d young\n",
- hum_regions, young_regions);
- gclog_or_tty->print("%d cur_alloc\n", cur_alloc);
- gclog_or_tty->print("UHOH unaccounted = %d\n", unaccounted);
- }
-};
-
-void G1CollectedHeap::print_region_counts() {
- SortHeapRegionClosure sc(_cur_alloc_region);
- PrintHeapRegionClosure cl;
- heap_region_iterate(&cl);
- heap_region_iterate(&sc);
- sc.print();
- print_region_accounting_info();
-};
-
-bool G1CollectedHeap::regions_accounted_for() {
- // TODO: regions accounting for young/survivor/tenured
- return true;
-}
-
-bool G1CollectedHeap::print_region_accounting_info() {
- gclog_or_tty->print_cr("Free regions: %d (count: %d count list %d) (clean: %d unclean: %d).",
- free_regions(),
- count_free_regions(), count_free_regions_list(),
- _free_region_list_size, _unclean_region_list.sz());
- gclog_or_tty->print_cr("cur_alloc: %d.",
- (_cur_alloc_region == NULL ? 0 : 1));
- gclog_or_tty->print_cr("H regions: %d.", _num_humongous_regions);
-
- // TODO: check regions accounting for young/survivor/tenured
- return true;
-}
+#ifdef ASSERT
bool G1CollectedHeap::is_in_closed_subset(const void* p) const {
HeapRegion* hr = heap_region_containing(p);
@@ -5802,8 +5438,84 @@
return hr->is_in(p);
}
}
-#endif // !PRODUCT
-
-void G1CollectedHeap::g1_unimplemented() {
- // Unimplemented();
+#endif // ASSERT
+
+class VerifyRegionListsClosure : public HeapRegionClosure {
+private:
+ HumongousRegionSet* _humongous_set;
+ FreeRegionList* _free_list;
+ size_t _region_count;
+
+public:
+ VerifyRegionListsClosure(HumongousRegionSet* humongous_set,
+ FreeRegionList* free_list) :
+ _humongous_set(humongous_set), _free_list(free_list),
+ _region_count(0) { }
+
+ size_t region_count() { return _region_count; }
+
+ bool doHeapRegion(HeapRegion* hr) {
+ _region_count += 1;
+
+ if (hr->continuesHumongous()) {
+ return false;
+ }
+
+ if (hr->is_young()) {
+ // TODO
+ } else if (hr->startsHumongous()) {
+ _humongous_set->verify_next_region(hr);
+ } else if (hr->is_empty()) {
+ _free_list->verify_next_region(hr);
+ }
+ return false;
+ }
+};
+
+void G1CollectedHeap::verify_region_sets() {
+ assert_heap_locked_or_at_safepoint(true /* should_be_vm_thread */);
+
+ // First, check the explicit lists.
+ _free_list.verify();
+ {
+ // Given that a concurrent operation might be adding regions to
+ // the secondary free list we have to take the lock before
+ // verifying it.
+ MutexLockerEx x(SecondaryFreeList_lock, Mutex::_no_safepoint_check_flag);
+ _secondary_free_list.verify();
+ }
+ _humongous_set.verify();
+
+ // If a concurrent region freeing operation is in progress it will
+ // be difficult to correctly attributed any free regions we come
+ // across to the correct free list given that they might belong to
+ // one of several (free_list, secondary_free_list, any local lists,
+ // etc.). So, if that's the case we will skip the rest of the
+ // verification operation. Alternatively, waiting for the concurrent
+ // operation to complete will have a non-trivial effect on the GC's
+ // operation (no concurrent operation will last longer than the
+ // interval between two calls to verification) and it might hide
+ // any issues that we would like to catch during testing.
+ if (free_regions_coming()) {
+ return;
+ }
+
+ {
+ MutexLockerEx x(SecondaryFreeList_lock, Mutex::_no_safepoint_check_flag);
+ // Make sure we append the secondary_free_list on the free_list so
+ // that all free regions we will come across can be safely
+ // attributed to the free_list.
+ append_secondary_free_list();
+ }
+
+ // Finally, make sure that the region accounting in the lists is
+ // consistent with what we see in the heap.
+ _humongous_set.verify_start();
+ _free_list.verify_start();
+
+ VerifyRegionListsClosure cl(&_humongous_set, &_free_list);
+ heap_region_iterate(&cl);
+
+ _humongous_set.verify_end();
+ _free_list.verify_end();
}
--- a/hotspot/src/share/vm/gc_implementation/g1/g1CollectedHeap.hpp Wed Jan 19 19:24:34 2011 -0800
+++ b/hotspot/src/share/vm/gc_implementation/g1/g1CollectedHeap.hpp Thu Jan 20 13:57:12 2011 -0800
@@ -27,7 +27,7 @@
#include "gc_implementation/g1/concurrentMark.hpp"
#include "gc_implementation/g1/g1RemSet.hpp"
-#include "gc_implementation/g1/heapRegion.hpp"
+#include "gc_implementation/g1/heapRegionSets.hpp"
#include "gc_implementation/parNew/parGCAllocBuffer.hpp"
#include "memory/barrierSet.hpp"
#include "memory/memRegion.hpp"
@@ -66,8 +66,7 @@
enum G1GCThreadGroups {
G1CRGroup = 0,
G1ZFGroup = 1,
- G1CMGroup = 2,
- G1CLGroup = 3
+ G1CMGroup = 2
};
enum GCAllocPurpose {
@@ -155,6 +154,7 @@
friend class RefineCardTableEntryClosure;
friend class G1PrepareCompactClosure;
friend class RegionSorter;
+ friend class RegionResetter;
friend class CountRCClosure;
friend class EvacPopObjClosure;
friend class G1ParCleanupCTTask;
@@ -178,17 +178,20 @@
// The maximum part of _g1_storage that has ever been committed.
MemRegion _g1_max_committed;
- // The number of regions that are completely free.
- size_t _free_regions;
+ // The master free list. It will satisfy all new region allocations.
+ MasterFreeRegionList _free_list;
+
+ // The secondary free list which contains regions that have been
+ // freed up during the cleanup process. This will be appended to the
+ // master free list when appropriate.
+ SecondaryFreeRegionList _secondary_free_list;
+
+ // It keeps track of the humongous regions.
+ MasterHumongousRegionSet _humongous_set;
// The number of regions we could create by expansion.
size_t _expansion_regions;
- // Return the number of free regions in the heap (by direct counting.)
- size_t count_free_regions();
- // Return the number of free regions on the free and unclean lists.
- size_t count_free_regions_list();
-
// The block offset table for the G1 heap.
G1BlockOffsetSharedArray* _bot_shared;
@@ -196,9 +199,6 @@
// lists, before and after full GC.
void tear_down_region_lists();
void rebuild_region_lists();
- // This sets all non-empty regions to need zero-fill (which they will if
- // they are empty after full collection.)
- void set_used_regions_to_need_zero_fill();
// The sequence of all heap regions in the heap.
HeapRegionSeq* _hrs;
@@ -231,7 +231,7 @@
// Determines PLAB size for a particular allocation purpose.
static size_t desired_plab_sz(GCAllocPurpose purpose);
- // When called by par thread, require par_alloc_during_gc_lock() to be held.
+ // When called by par thread, requires the FreeList_lock to be held.
void push_gc_alloc_region(HeapRegion* hr);
// This should only be called single-threaded. Undeclares all GC alloc
@@ -294,10 +294,11 @@
// line number, file, etc.
#define heap_locking_asserts_err_msg(__extra_message) \
- err_msg("%s : Heap_lock %slocked, %sat a safepoint", \
+ err_msg("%s : Heap_lock locked: %s, at safepoint: %s, is VM thread: %s", \
(__extra_message), \
- (!Heap_lock->owned_by_self()) ? "NOT " : "", \
- (!SafepointSynchronize::is_at_safepoint()) ? "NOT " : "")
+ BOOL_TO_STR(Heap_lock->owned_by_self()), \
+ BOOL_TO_STR(SafepointSynchronize::is_at_safepoint()), \
+ BOOL_TO_STR(Thread::current()->is_VM_thread()))
#define assert_heap_locked() \
do { \
@@ -305,10 +306,11 @@
heap_locking_asserts_err_msg("should be holding the Heap_lock")); \
} while (0)
-#define assert_heap_locked_or_at_safepoint() \
+#define assert_heap_locked_or_at_safepoint(__should_be_vm_thread) \
do { \
assert(Heap_lock->owned_by_self() || \
- SafepointSynchronize::is_at_safepoint(), \
+ (SafepointSynchronize::is_at_safepoint() && \
+ ((__should_be_vm_thread) == Thread::current()->is_VM_thread())), \
heap_locking_asserts_err_msg("should be holding the Heap_lock or " \
"should be at a safepoint")); \
} while (0)
@@ -335,9 +337,10 @@
"should not be at a safepoint")); \
} while (0)
-#define assert_at_safepoint() \
+#define assert_at_safepoint(__should_be_vm_thread) \
do { \
- assert(SafepointSynchronize::is_at_safepoint(), \
+ assert(SafepointSynchronize::is_at_safepoint() && \
+ ((__should_be_vm_thread) == Thread::current()->is_VM_thread()), \
heap_locking_asserts_err_msg("should be at a safepoint")); \
} while (0)
@@ -362,31 +365,41 @@
// The current policy object for the collector.
G1CollectorPolicy* _g1_policy;
- // Parallel allocation lock to protect the current allocation region.
- Mutex _par_alloc_during_gc_lock;
- Mutex* par_alloc_during_gc_lock() { return &_par_alloc_during_gc_lock; }
+ // This is the second level of trying to allocate a new region. If
+ // new_region_work didn't find a region in the free_list, this call
+ // will check whether there's anything available in the
+ // secondary_free_list and/or wait for more regions to appear in that
+ // list, if _free_regions_coming is set.
+ HeapRegion* new_region_try_secondary_free_list(size_t word_size);
- // If possible/desirable, allocate a new HeapRegion for normal object
- // allocation sufficient for an allocation of the given "word_size".
- // If "do_expand" is true, will attempt to expand the heap if necessary
- // to to satisfy the request. If "zero_filled" is true, requires a
- // zero-filled region.
- // (Returning NULL will trigger a GC.)
- virtual HeapRegion* newAllocRegion_work(size_t word_size,
- bool do_expand,
- bool zero_filled);
+ // It will try to allocate a single non-humongous HeapRegion
+ // sufficient for an allocation of the given word_size. If
+ // do_expand is true, it will attempt to expand the heap if
+ // necessary to satisfy the allocation request. Note that word_size
+ // is only used to make sure that we expand sufficiently but, given
+ // that the allocation request is assumed not to be humongous,
+ // having word_size is not strictly necessary (expanding by a single
+ // region will always be sufficient). But let's keep that parameter
+ // in case we need it in the future.
+ HeapRegion* new_region_work(size_t word_size, bool do_expand);
- virtual HeapRegion* newAllocRegion(size_t word_size,
- bool zero_filled = true) {
- return newAllocRegion_work(word_size, false, zero_filled);
+ // It will try to allocate a new region to be used for allocation by
+ // mutator threads. It will not try to expand the heap if not region
+ // is available.
+ HeapRegion* new_alloc_region(size_t word_size) {
+ return new_region_work(word_size, false /* do_expand */);
}
- virtual HeapRegion* newAllocRegionWithExpansion(int purpose,
- size_t word_size,
- bool zero_filled = true);
+
+ // It will try to allocate a new region to be used for allocation by
+ // a GC thread. It will try to expand the heap if no region is
+ // available.
+ HeapRegion* new_gc_alloc_region(int purpose, size_t word_size);
+
+ int humongous_obj_allocate_find_first(size_t num_regions, size_t word_size);
// Attempt to allocate an object of the given (very large) "word_size".
// Returns "NULL" on failure.
- virtual HeapWord* humongous_obj_allocate(size_t word_size);
+ HeapWord* humongous_obj_allocate(size_t word_size);
// The following two methods, allocate_new_tlab() and
// mem_allocate(), are the two main entry points from the runtime
@@ -760,20 +773,29 @@
// Invoke "save_marks" on all heap regions.
void save_marks();
- // Free a heap region.
- void free_region(HeapRegion* hr);
- // A component of "free_region", exposed for 'batching'.
- // All the params after "hr" are out params: the used bytes of the freed
- // region(s), the number of H regions cleared, the number of regions
- // freed, and pointers to the head and tail of a list of freed contig
- // regions, linked throught the "next_on_unclean_list" field.
- void free_region_work(HeapRegion* hr,
- size_t& pre_used,
- size_t& cleared_h,
- size_t& freed_regions,
- UncleanRegionList* list,
- bool par = false);
+ // It frees a non-humongous region by initializing its contents and
+ // adding it to the free list that's passed as a parameter (this is
+ // usually a local list which will be appended to the master free
+ // list later). The used bytes of freed regions are accumulated in
+ // pre_used. If par is true, the region's RSet will not be freed
+ // up. The assumption is that this will be done later.
+ void free_region(HeapRegion* hr,
+ size_t* pre_used,
+ FreeRegionList* free_list,
+ bool par);
+ // It frees a humongous region by collapsing it into individual
+ // regions and calling free_region() for each of them. The freed
+ // regions will be added to the free list that's passed as a parameter
+ // (this is usually a local list which will be appended to the
+ // master free list later). The used bytes of freed regions are
+ // accumulated in pre_used. If par is true, the region's RSet will
+ // not be freed up. The assumption is that this will be done later.
+ void free_humongous_region(HeapRegion* hr,
+ size_t* pre_used,
+ FreeRegionList* free_list,
+ HumongousRegionSet* humongous_proxy_set,
+ bool par);
// The concurrent marker (and the thread it runs in.)
ConcurrentMark* _cm;
@@ -783,9 +805,6 @@
// The concurrent refiner.
ConcurrentG1Refine* _cg1r;
- // The concurrent zero-fill thread.
- ConcurrentZFThread* _czft;
-
// The parallel task queues
RefToScanQueueSet *_task_queues;
@@ -877,9 +896,7 @@
SubTasksDone* _process_strong_tasks;
- // List of regions which require zero filling.
- UncleanRegionList _unclean_region_list;
- bool _unclean_regions_coming;
+ volatile bool _free_regions_coming;
public:
@@ -1002,71 +1019,64 @@
size_t max_regions();
// The number of regions that are completely free.
- size_t free_regions();
+ size_t free_regions() {
+ return _free_list.length();
+ }
// The number of regions that are not completely free.
size_t used_regions() { return n_regions() - free_regions(); }
- // True iff the ZF thread should run.
- bool should_zf();
-
// The number of regions available for "regular" expansion.
size_t expansion_regions() { return _expansion_regions; }
-#ifndef PRODUCT
- bool regions_accounted_for();
- bool print_region_accounting_info();
- void print_region_counts();
-#endif
-
- HeapRegion* alloc_region_from_unclean_list(bool zero_filled);
- HeapRegion* alloc_region_from_unclean_list_locked(bool zero_filled);
-
- void put_region_on_unclean_list(HeapRegion* r);
- void put_region_on_unclean_list_locked(HeapRegion* r);
+ // verify_region_sets() performs verification over the region
+ // lists. It will be compiled in the product code to be used when
+ // necessary (i.e., during heap verification).
+ void verify_region_sets();
- void prepend_region_list_on_unclean_list(UncleanRegionList* list);
- void prepend_region_list_on_unclean_list_locked(UncleanRegionList* list);
+ // verify_region_sets_optional() is planted in the code for
+ // list verification in non-product builds (and it can be enabled in
+ // product builds by definning HEAP_REGION_SET_FORCE_VERIFY to be 1).
+#if HEAP_REGION_SET_FORCE_VERIFY
+ void verify_region_sets_optional() {
+ verify_region_sets();
+ }
+#else // HEAP_REGION_SET_FORCE_VERIFY
+ void verify_region_sets_optional() { }
+#endif // HEAP_REGION_SET_FORCE_VERIFY
- void set_unclean_regions_coming(bool b);
- void set_unclean_regions_coming_locked(bool b);
- // Wait for cleanup to be complete.
- void wait_for_cleanup_complete();
- // Like above, but assumes that the calling thread owns the Heap_lock.
- void wait_for_cleanup_complete_locked();
-
- // Return the head of the unclean list.
- HeapRegion* peek_unclean_region_list_locked();
- // Remove and return the head of the unclean list.
- HeapRegion* pop_unclean_region_list_locked();
+#ifdef ASSERT
+ bool is_on_free_list(HeapRegion* hr) {
+ return hr->containing_set() == &_free_list;
+ }
- // List of regions which are zero filled and ready for allocation.
- HeapRegion* _free_region_list;
- // Number of elements on the free list.
- size_t _free_region_list_size;
+ bool is_on_humongous_set(HeapRegion* hr) {
+ return hr->containing_set() == &_humongous_set;
+}
+#endif // ASSERT
- // If the head of the unclean list is ZeroFilled, move it to the free
- // list.
- bool move_cleaned_region_to_free_list_locked();
- bool move_cleaned_region_to_free_list();
+ // Wrapper for the region list operations that can be called from
+ // methods outside this class.
- void put_free_region_on_list_locked(HeapRegion* r);
- void put_free_region_on_list(HeapRegion* r);
+ void secondary_free_list_add_as_tail(FreeRegionList* list) {
+ _secondary_free_list.add_as_tail(list);
+ }
- // Remove and return the head element of the free list.
- HeapRegion* pop_free_region_list_locked();
+ void append_secondary_free_list() {
+ _free_list.add_as_tail(&_secondary_free_list);
+ }
- // If "zero_filled" is true, we first try the free list, then we try the
- // unclean list, zero-filling the result. If "zero_filled" is false, we
- // first try the unclean list, then the zero-filled list.
- HeapRegion* alloc_free_region_from_lists(bool zero_filled);
+ void append_secondary_free_list_if_not_empty() {
+ if (!_secondary_free_list.is_empty()) {
+ MutexLockerEx x(SecondaryFreeList_lock, Mutex::_no_safepoint_check_flag);
+ append_secondary_free_list();
+ }
+ }
- // Verify the integrity of the region lists.
- void remove_allocated_regions_from_lists();
- bool verify_region_lists();
- bool verify_region_lists_locked();
- size_t unclean_region_list_length();
- size_t free_region_list_length();
+ void set_free_regions_coming();
+ void reset_free_regions_coming();
+ bool free_regions_coming() { return _free_regions_coming; }
+ void wait_while_free_regions_coming();
// Perform a collection of the heap; intended for use in implementing
// "System.gc". This probably implies as full a collection as the
@@ -1085,23 +1095,24 @@
// True iff a evacuation has failed in the most-recent collection.
bool evacuation_failed() { return _evacuation_failed; }
- // Free a region if it is totally full of garbage. Returns the number of
- // bytes freed (0 ==> didn't free it).
- size_t free_region_if_totally_empty(HeapRegion *hr);
- void free_region_if_totally_empty_work(HeapRegion *hr,
- size_t& pre_used,
- size_t& cleared_h_regions,
- size_t& freed_regions,
- UncleanRegionList* list,
- bool par = false);
+ // It will free a region if it has allocated objects in it that are
+ // all dead. It calls either free_region() or
+ // free_humongous_region() depending on the type of the region that
+ // is passed to it.
+ void free_region_if_totally_empty(HeapRegion* hr,
+ size_t* pre_used,
+ FreeRegionList* free_list,
+ HumongousRegionSet* humongous_proxy_set,
+ bool par);
- // If we've done free region work that yields the given changes, update
- // the relevant global variables.
- void finish_free_region_work(size_t pre_used,
- size_t cleared_h_regions,
- size_t freed_regions,
- UncleanRegionList* list);
-
+ // It appends the free list to the master free list and updates the
+ // master humongous list according to the contents of the proxy
+ // list. It also adjusts the total used bytes according to pre_used
+ // (if par is true, it will do so by taking the ParGCRareEvent_lock).
+ void update_sets_after_freeing_regions(size_t pre_used,
+ FreeRegionList* free_list,
+ HumongousRegionSet* humongous_proxy_set,
+ bool par);
// Returns "TRUE" iff "p" points into the allocated area of the heap.
virtual bool is_in(const void* p) const;
@@ -1314,8 +1325,6 @@
return true;
}
- virtual bool allocs_are_zero_filled();
-
// The boundary between a "large" and "small" array of primitives, in
// words.
virtual size_t large_typearray_limit();
@@ -1546,13 +1555,6 @@
protected:
size_t _max_heap_capacity;
-
-public:
- // Temporary: call to mark things unimplemented for the G1 heap (e.g.,
- // MemoryService). In productization, we can make this assert false
- // to catch such places (as well as searching for calls to this...)
- static void g1_unimplemented();
-
};
#define use_local_bitmaps 1
--- a/hotspot/src/share/vm/gc_implementation/g1/g1CollectedHeap.inline.hpp Wed Jan 19 19:24:34 2011 -0800
+++ b/hotspot/src/share/vm/gc_implementation/g1/g1CollectedHeap.inline.hpp Thu Jan 20 13:57:12 2011 -0800
@@ -28,7 +28,7 @@
#include "gc_implementation/g1/concurrentMark.hpp"
#include "gc_implementation/g1/g1CollectedHeap.hpp"
#include "gc_implementation/g1/g1CollectorPolicy.hpp"
-#include "gc_implementation/g1/heapRegionSeq.hpp"
+#include "gc_implementation/g1/heapRegionSeq.inline.hpp"
#include "utilities/taskqueue.hpp"
// Inline functions for G1CollectedHeap
@@ -135,7 +135,7 @@
inline void
G1CollectedHeap::retire_cur_alloc_region_common(HeapRegion* cur_alloc_region) {
- assert_heap_locked_or_at_safepoint();
+ assert_heap_locked_or_at_safepoint(true /* should_be_vm_thread */);
assert(cur_alloc_region != NULL && cur_alloc_region == _cur_alloc_region,
"pre-condition of the call");
assert(cur_alloc_region->is_young(),
--- a/hotspot/src/share/vm/gc_implementation/g1/g1CollectorPolicy.cpp Wed Jan 19 19:24:34 2011 -0800
+++ b/hotspot/src/share/vm/gc_implementation/g1/g1CollectorPolicy.cpp Thu Jan 20 13:57:12 2011 -0800
@@ -1,5 +1,5 @@
/*
- * Copyright (c) 2001, 2010, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2001, 2011, 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
@@ -2875,8 +2875,6 @@
// Adjust for expansion and slop.
max_live_bytes = max_live_bytes + expansion_bytes;
- assert(_g1->regions_accounted_for(), "Region leakage!");
-
HeapRegion* hr;
if (in_young_gc_mode()) {
double young_start_time_sec = os::elapsedTime();
--- a/hotspot/src/share/vm/gc_implementation/g1/g1MarkSweep.cpp Wed Jan 19 19:24:34 2011 -0800
+++ b/hotspot/src/share/vm/gc_implementation/g1/g1MarkSweep.cpp Thu Jan 20 13:57:12 2011 -0800
@@ -1,5 +1,5 @@
/*
- * Copyright (c) 2001, 2010, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2001, 2011, 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
@@ -181,26 +181,46 @@
}
class G1PrepareCompactClosure: public HeapRegionClosure {
+ G1CollectedHeap* _g1h;
ModRefBarrierSet* _mrbs;
CompactPoint _cp;
+ size_t _pre_used;
+ FreeRegionList _free_list;
+ HumongousRegionSet _humongous_proxy_set;
void free_humongous_region(HeapRegion* hr) {
- HeapWord* bot = hr->bottom();
HeapWord* end = hr->end();
assert(hr->startsHumongous(),
"Only the start of a humongous region should be freed.");
- G1CollectedHeap::heap()->free_region(hr);
+ _g1h->free_humongous_region(hr, &_pre_used, &_free_list,
+ &_humongous_proxy_set, false /* par */);
+ // Do we also need to do this for the continues humongous regions
+ // we just collapsed?
hr->prepare_for_compaction(&_cp);
// Also clear the part of the card table that will be unused after
// compaction.
- _mrbs->clear(MemRegion(hr->compaction_top(), hr->end()));
+ _mrbs->clear(MemRegion(hr->compaction_top(), end));
}
public:
- G1PrepareCompactClosure(CompactibleSpace* cs) :
+ G1PrepareCompactClosure(CompactibleSpace* cs)
+ : _g1h(G1CollectedHeap::heap()),
+ _mrbs(G1CollectedHeap::heap()->mr_bs()),
_cp(NULL, cs, cs->initialize_threshold()),
- _mrbs(G1CollectedHeap::heap()->mr_bs())
- {}
+ _pre_used(0),
+ _free_list("Local Free List for G1MarkSweep"),
+ _humongous_proxy_set("G1MarkSweep Humongous Proxy Set") { }
+
+ void update_sets() {
+ // We'll recalculate total used bytes and recreate the free list
+ // at the end of the GC, so no point in updating those values here.
+ _g1h->update_sets_after_freeing_regions(0, /* pre_used */
+ NULL, /* free_list */
+ &_humongous_proxy_set,
+ false /* par */);
+ _free_list.remove_all();
+ }
+
bool doHeapRegion(HeapRegion* hr) {
if (hr->isHumongous()) {
if (hr->startsHumongous()) {
@@ -266,6 +286,7 @@
G1PrepareCompactClosure blk(sp);
g1h->heap_region_iterate(&blk);
+ blk.update_sets();
CompactPoint perm_cp(pg, NULL, NULL);
pg->prepare_for_compaction(&perm_cp);
--- a/hotspot/src/share/vm/gc_implementation/g1/g1_globals.hpp Wed Jan 19 19:24:34 2011 -0800
+++ b/hotspot/src/share/vm/gc_implementation/g1/g1_globals.hpp Thu Jan 20 13:57:12 2011 -0800
@@ -1,5 +1,5 @@
/*
- * Copyright (c) 2001, 2010, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2001, 2011, 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
@@ -75,21 +75,12 @@
"(0 means do not periodically generate this info); " \
"it also requires -XX:+G1SummarizeRSetStats") \
\
- diagnostic(bool, G1SummarizeZFStats, false, \
- "Summarize zero-filling info") \
- \
diagnostic(bool, G1TraceConcRefinement, false, \
"Trace G1 concurrent refinement") \
\
product(intx, G1MarkRegionStackSize, 1024 * 1024, \
"Size of the region stack for concurrent marking.") \
\
- develop(bool, G1ConcZeroFill, true, \
- "If true, run concurrent zero-filling thread") \
- \
- develop(intx, G1ConcZFMaxRegions, 1, \
- "Stop zero-filling when # of zf'd regions reaches") \
- \
develop(bool, G1SATBBarrierPrintNullPreVals, false, \
"If true, count frac of ptr writes with null pre-vals.") \
\
@@ -99,6 +90,13 @@
develop(intx, G1SATBProcessCompletedThreshold, 20, \
"Number of completed buffers that triggers log processing.") \
\
+ product(uintx, G1SATBBufferEnqueueingThresholdPercent, 60, \
+ "Before enqueueing them, each mutator thread tries to do some " \
+ "filtering on the SATB buffers it generates. If post-filtering " \
+ "the percentage of retained entries is over this threshold " \
+ "the buffer will be enqueued for processing. A value of 0 " \
+ "specifies that mutator threads should not do such filtering.") \
+ \
develop(intx, G1ExtraRegionSurvRate, 33, \
"If the young survival rate is S, and there's room left in " \
"to-space, we will allow regions whose survival rate is up to " \
@@ -282,7 +280,20 @@
"Size of a work unit of cards claimed by a worker thread" \
"during RSet scanning.") \
\
- develop(bool, ReduceInitialCardMarksForG1, false, \
+ develop(uintx, G1SecondaryFreeListAppendLength, 5, \
+ "The number of regions we will add to the secondary free list " \
+ "at every append operation") \
+ \
+ develop(bool, G1ConcRegionFreeingVerbose, false, \
+ "Enables verboseness during concurrent region freeing") \
+ \
+ develop(bool, G1StressConcRegionFreeing, false, \
+ "It stresses the concurrent region freeing operation") \
+ \
+ develop(uintx, G1StressConcRegionFreeingDelayMillis, 0, \
+ "Artificial delay during concurrent region freeing") \
+ \
+ develop(bool, ReduceInitialCardMarksForG1, false, \
"When ReduceInitialCardMarks is true, this flag setting " \
" controls whether G1 allows the RICM optimization")
--- a/hotspot/src/share/vm/gc_implementation/g1/heapRegion.cpp Wed Jan 19 19:24:34 2011 -0800
+++ b/hotspot/src/share/vm/gc_implementation/g1/heapRegion.cpp Thu Jan 20 13:57:12 2011 -0800
@@ -23,7 +23,6 @@
*/
#include "precompiled.hpp"
-#include "gc_implementation/g1/concurrentZFThread.hpp"
#include "gc_implementation/g1/g1BlockOffsetTable.inline.hpp"
#include "gc_implementation/g1/g1CollectedHeap.inline.hpp"
#include "gc_implementation/g1/g1OopClosures.inline.hpp"
@@ -348,22 +347,20 @@
}
void HeapRegion::hr_clear(bool par, bool clear_space) {
- _humongous_type = NotHumongous;
- _humongous_start_region = NULL;
+ assert(_humongous_type == NotHumongous,
+ "we should have already filtered out humongous regions");
+ assert(_humongous_start_region == NULL,
+ "we should have already filtered out humongous regions");
+ assert(_end == _orig_end,
+ "we should have already filtered out humongous regions");
+
_in_collection_set = false;
_is_gc_alloc_region = false;
- // Age stuff (if parallel, this will be done separately, since it needs
- // to be sequential).
- G1CollectedHeap* g1h = G1CollectedHeap::heap();
-
set_young_index_in_cset(-1);
uninstall_surv_rate_group();
set_young_type(NotYoung);
- // In case it had been the start of a humongous sequence, reset its end.
- set_end(_orig_end);
-
if (!par) {
// If this is parallel, this will be done later.
HeapRegionRemSet* hrrs = rem_set();
@@ -387,6 +384,7 @@
// </PREDICTION>
void HeapRegion::set_startsHumongous(HeapWord* new_top, HeapWord* new_end) {
+ assert(!isHumongous(), "sanity / pre-condition");
assert(end() == _orig_end,
"Should be normal before the humongous object allocation");
assert(top() == bottom(), "should be empty");
@@ -400,6 +398,7 @@
}
void HeapRegion::set_continuesHumongous(HeapRegion* first_hr) {
+ assert(!isHumongous(), "sanity / pre-condition");
assert(end() == _orig_end,
"Should be normal before the humongous object allocation");
assert(top() == bottom(), "should be empty");
@@ -409,6 +408,26 @@
_humongous_start_region = first_hr;
}
+void HeapRegion::set_notHumongous() {
+ assert(isHumongous(), "pre-condition");
+
+ if (startsHumongous()) {
+ assert(top() <= end(), "pre-condition");
+ set_end(_orig_end);
+ if (top() > end()) {
+ // at least one "continues humongous" region after it
+ set_top(end());
+ }
+ } else {
+ // continues humongous
+ assert(end() == _orig_end, "sanity");
+ }
+
+ assert(capacity() == (size_t) HeapRegion::GrainBytes, "pre-condition");
+ _humongous_type = NotHumongous;
+ _humongous_start_region = NULL;
+}
+
bool HeapRegion::claimHeapRegion(jint claimValue) {
jint current = _claimed;
if (current != claimValue) {
@@ -443,15 +462,6 @@
return low;
}
-void HeapRegion::set_next_on_unclean_list(HeapRegion* r) {
- assert(r == NULL || r->is_on_unclean_list(), "Malformed unclean list.");
- _next_in_special_set = r;
-}
-
-void HeapRegion::set_on_unclean_list(bool b) {
- _is_on_unclean_list = b;
-}
-
void HeapRegion::initialize(MemRegion mr, bool clear_space, bool mangle_space) {
G1OffsetTableContigSpace::initialize(mr, false, mangle_space);
hr_clear(false/*par*/, clear_space);
@@ -469,15 +479,16 @@
_hrs_index(-1),
_humongous_type(NotHumongous), _humongous_start_region(NULL),
_in_collection_set(false), _is_gc_alloc_region(false),
- _is_on_free_list(false), _is_on_unclean_list(false),
_next_in_special_set(NULL), _orig_end(NULL),
_claimed(InitialClaimValue), _evacuation_failed(false),
_prev_marked_bytes(0), _next_marked_bytes(0), _sort_index(-1),
_young_type(NotYoung), _next_young_region(NULL),
- _next_dirty_cards_region(NULL),
- _young_index_in_cset(-1), _surv_rate_group(NULL), _age_index(-1),
- _rem_set(NULL), _zfs(NotZeroFilled),
- _recorded_rs_length(0), _predicted_elapsed_time_ms(0),
+ _next_dirty_cards_region(NULL), _next(NULL), _pending_removal(false),
+#ifdef ASSERT
+ _containing_set(NULL),
+#endif // ASSERT
+ _young_index_in_cset(-1), _surv_rate_group(NULL), _age_index(-1),
+ _rem_set(NULL), _recorded_rs_length(0), _predicted_elapsed_time_ms(0),
_predicted_bytes_to_copy(0)
{
_orig_end = mr.end();
@@ -552,86 +563,6 @@
oops_in_mr_iterate(MemRegion(bottom(), saved_mark_word()), cl);
}
-#ifdef DEBUG
-HeapWord* HeapRegion::allocate(size_t size) {
- jint state = zero_fill_state();
- assert(!G1CollectedHeap::heap()->allocs_are_zero_filled() ||
- zero_fill_is_allocated(),
- "When ZF is on, only alloc in ZF'd regions");
- return G1OffsetTableContigSpace::allocate(size);
-}
-#endif
-
-void HeapRegion::set_zero_fill_state_work(ZeroFillState zfs) {
- assert(ZF_mon->owned_by_self() ||
- Universe::heap()->is_gc_active(),
- "Must hold the lock or be a full GC to modify.");
-#ifdef ASSERT
- if (top() != bottom() && zfs != Allocated) {
- ResourceMark rm;
- stringStream region_str;
- print_on(®ion_str);
- assert(top() == bottom() || zfs == Allocated,
- err_msg("Region must be empty, or we must be setting it to allocated. "
- "_zfs=%d, zfs=%d, region: %s", _zfs, zfs, region_str.as_string()));
- }
-#endif
- _zfs = zfs;
-}
-
-void HeapRegion::set_zero_fill_complete() {
- set_zero_fill_state_work(ZeroFilled);
- if (ZF_mon->owned_by_self()) {
- ZF_mon->notify_all();
- }
-}
-
-
-void HeapRegion::ensure_zero_filled() {
- MutexLockerEx x(ZF_mon, Mutex::_no_safepoint_check_flag);
- ensure_zero_filled_locked();
-}
-
-void HeapRegion::ensure_zero_filled_locked() {
- assert(ZF_mon->owned_by_self(), "Precondition");
- bool should_ignore_zf = SafepointSynchronize::is_at_safepoint();
- assert(should_ignore_zf || Heap_lock->is_locked(),
- "Either we're in a GC or we're allocating a region.");
- switch (zero_fill_state()) {
- case HeapRegion::NotZeroFilled:
- set_zero_fill_in_progress(Thread::current());
- {
- ZF_mon->unlock();
- Copy::fill_to_words(bottom(), capacity()/HeapWordSize);
- ZF_mon->lock_without_safepoint_check();
- }
- // A trap.
- guarantee(zero_fill_state() == HeapRegion::ZeroFilling
- && zero_filler() == Thread::current(),
- "AHA! Tell Dave D if you see this...");
- set_zero_fill_complete();
- // gclog_or_tty->print_cr("Did sync ZF.");
- ConcurrentZFThread::note_sync_zfs();
- break;
- case HeapRegion::ZeroFilling:
- if (should_ignore_zf) {
- // We can "break" the lock and take over the work.
- Copy::fill_to_words(bottom(), capacity()/HeapWordSize);
- set_zero_fill_complete();
- ConcurrentZFThread::note_sync_zfs();
- break;
- } else {
- ConcurrentZFThread::wait_for_ZF_completed(this);
- }
- case HeapRegion::ZeroFilled:
- // Nothing to do.
- break;
- case HeapRegion::Allocated:
- guarantee(false, "Should not call on allocated regions.");
- }
- assert(zero_fill_state() == HeapRegion::ZeroFilled, "Post");
-}
-
HeapWord*
HeapRegion::object_iterate_mem_careful(MemRegion mr,
ObjectClosure* cl) {
@@ -1010,67 +941,3 @@
_offsets.set_space(this);
initialize(mr, !is_zeroed, SpaceDecorator::Mangle);
}
-
-size_t RegionList::length() {
- size_t len = 0;
- HeapRegion* cur = hd();
- DEBUG_ONLY(HeapRegion* last = NULL);
- while (cur != NULL) {
- len++;
- DEBUG_ONLY(last = cur);
- cur = get_next(cur);
- }
- assert(last == tl(), "Invariant");
- return len;
-}
-
-void RegionList::insert_before_head(HeapRegion* r) {
- assert(well_formed(), "Inv");
- set_next(r, hd());
- _hd = r;
- _sz++;
- if (tl() == NULL) _tl = r;
- assert(well_formed(), "Inv");
-}
-
-void RegionList::prepend_list(RegionList* new_list) {
- assert(well_formed(), "Precondition");
- assert(new_list->well_formed(), "Precondition");
- HeapRegion* new_tl = new_list->tl();
- if (new_tl != NULL) {
- set_next(new_tl, hd());
- _hd = new_list->hd();
- _sz += new_list->sz();
- if (tl() == NULL) _tl = new_list->tl();
- } else {
- assert(new_list->hd() == NULL && new_list->sz() == 0, "Inv");
- }
- assert(well_formed(), "Inv");
-}
-
-void RegionList::delete_after(HeapRegion* r) {
- assert(well_formed(), "Precondition");
- HeapRegion* next = get_next(r);
- assert(r != NULL, "Precondition");
- HeapRegion* next_tl = get_next(next);
- set_next(r, next_tl);
- dec_sz();
- if (next == tl()) {
- assert(next_tl == NULL, "Inv");
- _tl = r;
- }
- assert(well_formed(), "Inv");
-}
-
-HeapRegion* RegionList::pop() {
- assert(well_formed(), "Inv");
- HeapRegion* res = hd();
- if (res != NULL) {
- _hd = get_next(res);
- _sz--;
- set_next(res, NULL);
- if (sz() == 0) _tl = NULL;
- }
- assert(well_formed(), "Inv");
- return res;
-}
--- a/hotspot/src/share/vm/gc_implementation/g1/heapRegion.hpp Wed Jan 19 19:24:34 2011 -0800
+++ b/hotspot/src/share/vm/gc_implementation/g1/heapRegion.hpp Thu Jan 20 13:57:12 2011 -0800
@@ -50,6 +50,11 @@
class HeapRegionRemSet;
class HeapRegionRemSetIterator;
class HeapRegion;
+class HeapRegionSetBase;
+
+#define HR_FORMAT "%d:["PTR_FORMAT","PTR_FORMAT","PTR_FORMAT"]"
+#define HR_FORMAT_PARAMS(__hr) (__hr)->hrs_index(), (__hr)->bottom(), \
+ (__hr)->top(), (__hr)->end()
// A dirty card to oop closure for heap regions. It
// knows how to get the G1 heap and how to use the bitmap
@@ -227,12 +232,6 @@
// True iff the region is in current collection_set.
bool _in_collection_set;
- // True iff the region is on the unclean list, waiting to be zero filled.
- bool _is_on_unclean_list;
-
- // True iff the region is on the free list, ready for allocation.
- bool _is_on_free_list;
-
// Is this or has it been an allocation region in the current collection
// pause.
bool _is_gc_alloc_region;
@@ -254,6 +253,13 @@
// Next region whose cards need cleaning
HeapRegion* _next_dirty_cards_region;
+ // Fields used by the HeapRegionSetBase class and subclasses.
+ HeapRegion* _next;
+#ifdef ASSERT
+ HeapRegionSetBase* _containing_set;
+#endif // ASSERT
+ bool _pending_removal;
+
// For parallel heapRegion traversal.
jint _claimed;
@@ -305,10 +311,6 @@
_top_at_conc_mark_count = bot;
}
- jint _zfs; // A member of ZeroFillState. Protected by ZF_lock.
- Thread* _zero_filler; // If _zfs is ZeroFilling, the thread that (last)
- // made it so.
-
void set_young_type(YoungType new_type) {
//assert(_young_type != new_type, "setting the same type" );
// TODO: add more assertions here
@@ -362,16 +364,6 @@
RebuildRSClaimValue = 5
};
- // Concurrent refinement requires contiguous heap regions (in which TLABs
- // might be allocated) to be zero-filled. Each region therefore has a
- // zero-fill-state.
- enum ZeroFillState {
- NotZeroFilled,
- ZeroFilling,
- ZeroFilled,
- Allocated
- };
-
inline HeapWord* par_allocate_no_bot_updates(size_t word_size) {
assert(is_young(), "we can only skip BOT updates on young regions");
return ContiguousSpace::par_allocate(word_size);
@@ -456,6 +448,9 @@
// which this region will be part of.
void set_continuesHumongous(HeapRegion* first_hr);
+ // Unsets the humongous-related fields on the region.
+ void set_notHumongous();
+
// If the region has a remembered set, return a pointer to it.
HeapRegionRemSet* rem_set() const {
return _rem_set;
@@ -502,45 +497,56 @@
_next_in_special_set = r;
}
- bool is_on_free_list() {
- return _is_on_free_list;
- }
+ // Methods used by the HeapRegionSetBase class and subclasses.
- void set_on_free_list(bool b) {
- _is_on_free_list = b;
- }
+ // Getter and setter for the next field used to link regions into
+ // linked lists.
+ HeapRegion* next() { return _next; }
+
+ void set_next(HeapRegion* next) { _next = next; }
- HeapRegion* next_from_free_list() {
- assert(is_on_free_list(),
- "Should only invoke on free space.");
- assert(_next_in_special_set == NULL ||
- _next_in_special_set->is_on_free_list(),
- "Malformed Free List.");
- return _next_in_special_set;
- }
+ // Every region added to a set is tagged with a reference to that
+ // set. This is used for doing consistency checking to make sure that
+ // the contents of a set are as they should be and it's only
+ // available in non-product builds.
+#ifdef ASSERT
+ void set_containing_set(HeapRegionSetBase* containing_set) {
+ assert((containing_set == NULL && _containing_set != NULL) ||
+ (containing_set != NULL && _containing_set == NULL),
+ err_msg("containing_set: "PTR_FORMAT" "
+ "_containing_set: "PTR_FORMAT,
+ containing_set, _containing_set));
+
+ _containing_set = containing_set;
+}
- void set_next_on_free_list(HeapRegion* r) {
- assert(r == NULL || r->is_on_free_list(), "Malformed free list.");
- _next_in_special_set = r;
- }
+ HeapRegionSetBase* containing_set() { return _containing_set; }
+#else // ASSERT
+ void set_containing_set(HeapRegionSetBase* containing_set) { }
- bool is_on_unclean_list() {
- return _is_on_unclean_list;
- }
+ // containing_set() is only used in asserts so there's not reason
+ // to provide a dummy version of it.
+#endif // ASSERT
- void set_on_unclean_list(bool b);
+ // If we want to remove regions from a list in bulk we can simply tag
+ // them with the pending_removal tag and call the
+ // remove_all_pending() method on the list.
- HeapRegion* next_from_unclean_list() {
- assert(is_on_unclean_list(),
- "Should only invoke on unclean space.");
- assert(_next_in_special_set == NULL ||
- _next_in_special_set->is_on_unclean_list(),
- "Malformed unclean List.");
- return _next_in_special_set;
+ bool pending_removal() { return _pending_removal; }
+
+ void set_pending_removal(bool pending_removal) {
+ // We can only set pending_removal to true, if it's false and the
+ // region belongs to a set.
+ assert(!pending_removal ||
+ (!_pending_removal && containing_set() != NULL), "pre-condition");
+ // We can only set pending_removal to false, if it's true and the
+ // region does not belong to a set.
+ assert( pending_removal ||
+ ( _pending_removal && containing_set() == NULL), "pre-condition");
+
+ _pending_removal = pending_removal;
}
- void set_next_on_unclean_list(HeapRegion* r);
-
HeapRegion* get_next_young_region() { return _next_young_region; }
void set_next_young_region(HeapRegion* hr) {
_next_young_region = hr;
@@ -559,11 +565,6 @@
void initialize(MemRegion mr, bool clear_space, bool mangle_space);
- // Ensure that "this" is zero-filled.
- void ensure_zero_filled();
- // This one requires that the calling thread holds ZF_mon.
- void ensure_zero_filled_locked();
-
// Get the start of the unmarked area in this region.
HeapWord* prev_top_at_mark_start() const { return _prev_top_at_mark_start; }
HeapWord* next_top_at_mark_start() const { return _next_top_at_mark_start; }
@@ -798,36 +799,6 @@
// "end" of the region if there is no such block.
HeapWord* next_block_start_careful(HeapWord* addr);
- // Returns the zero-fill-state of the current region.
- ZeroFillState zero_fill_state() { return (ZeroFillState)_zfs; }
- bool zero_fill_is_allocated() { return _zfs == Allocated; }
- Thread* zero_filler() { return _zero_filler; }
-
- // Indicate that the contents of the region are unknown, and therefore
- // might require zero-filling.
- void set_zero_fill_needed() {
- set_zero_fill_state_work(NotZeroFilled);
- }
- void set_zero_fill_in_progress(Thread* t) {
- set_zero_fill_state_work(ZeroFilling);
- _zero_filler = t;
- }
- void set_zero_fill_complete();
- void set_zero_fill_allocated() {
- set_zero_fill_state_work(Allocated);
- }
-
- void set_zero_fill_state_work(ZeroFillState zfs);
-
- // This is called when a full collection shrinks the heap.
- // We want to set the heap region to a value which says
- // it is no longer part of the heap. For now, we'll let "NotZF" fill
- // that role.
- void reset_zero_fill() {
- set_zero_fill_state_work(NotZeroFilled);
- _zero_filler = NULL;
- }
-
size_t recorded_rs_length() const { return _recorded_rs_length; }
double predicted_elapsed_time_ms() const { return _predicted_elapsed_time_ms; }
size_t predicted_bytes_to_copy() const { return _predicted_bytes_to_copy; }
@@ -866,10 +837,6 @@
// Override; it uses the "prev" marking information
virtual void verify(bool allow_dirty) const;
-
-#ifdef DEBUG
- HeapWord* allocate(size_t size);
-#endif
};
// HeapRegionClosure is used for iterating over regions.
@@ -892,113 +859,6 @@
bool complete() { return _complete; }
};
-// A linked lists of heap regions. It leaves the "next" field
-// unspecified; that's up to subtypes.
-class RegionList VALUE_OBJ_CLASS_SPEC {
-protected:
- virtual HeapRegion* get_next(HeapRegion* chr) = 0;
- virtual void set_next(HeapRegion* chr,
- HeapRegion* new_next) = 0;
-
- HeapRegion* _hd;
- HeapRegion* _tl;
- size_t _sz;
-
- // Protected constructor because this type is only meaningful
- // when the _get/_set next functions are defined.
- RegionList() : _hd(NULL), _tl(NULL), _sz(0) {}
-public:
- void reset() {
- _hd = NULL;
- _tl = NULL;
- _sz = 0;
- }
- HeapRegion* hd() { return _hd; }
- HeapRegion* tl() { return _tl; }
- size_t sz() { return _sz; }
- size_t length();
-
- bool well_formed() {
- return
- ((hd() == NULL && tl() == NULL && sz() == 0)
- || (hd() != NULL && tl() != NULL && sz() > 0))
- && (sz() == length());
- }
- virtual void insert_before_head(HeapRegion* r);
- void prepend_list(RegionList* new_list);
- virtual HeapRegion* pop();
- void dec_sz() { _sz--; }
- // Requires that "r" is an element of the list, and is not the tail.
- void delete_after(HeapRegion* r);
-};
-
-class EmptyNonHRegionList: public RegionList {
-protected:
- // Protected constructor because this type is only meaningful
- // when the _get/_set next functions are defined.
- EmptyNonHRegionList() : RegionList() {}
-
-public:
- void insert_before_head(HeapRegion* r) {
- // assert(r->is_empty(), "Better be empty");
- assert(!r->isHumongous(), "Better not be humongous.");
- RegionList::insert_before_head(r);
- }
- void prepend_list(EmptyNonHRegionList* new_list) {
- // assert(new_list->hd() == NULL || new_list->hd()->is_empty(),
- // "Better be empty");
- assert(new_list->hd() == NULL || !new_list->hd()->isHumongous(),
- "Better not be humongous.");
- // assert(new_list->tl() == NULL || new_list->tl()->is_empty(),
- // "Better be empty");
- assert(new_list->tl() == NULL || !new_list->tl()->isHumongous(),
- "Better not be humongous.");
- RegionList::prepend_list(new_list);
- }
-};
-
-class UncleanRegionList: public EmptyNonHRegionList {
-public:
- HeapRegion* get_next(HeapRegion* hr) {
- return hr->next_from_unclean_list();
- }
- void set_next(HeapRegion* hr, HeapRegion* new_next) {
- hr->set_next_on_unclean_list(new_next);
- }
-
- UncleanRegionList() : EmptyNonHRegionList() {}
-
- void insert_before_head(HeapRegion* r) {
- assert(!r->is_on_free_list(),
- "Better not already be on free list");
- assert(!r->is_on_unclean_list(),
- "Better not already be on unclean list");
- r->set_zero_fill_needed();
- r->set_on_unclean_list(true);
- EmptyNonHRegionList::insert_before_head(r);
- }
- void prepend_list(UncleanRegionList* new_list) {
- assert(new_list->tl() == NULL || !new_list->tl()->is_on_free_list(),
- "Better not already be on free list");
- assert(new_list->tl() == NULL || new_list->tl()->is_on_unclean_list(),
- "Better already be marked as on unclean list");
- assert(new_list->hd() == NULL || !new_list->hd()->is_on_free_list(),
- "Better not already be on free list");
- assert(new_list->hd() == NULL || new_list->hd()->is_on_unclean_list(),
- "Better already be marked as on unclean list");
- EmptyNonHRegionList::prepend_list(new_list);
- }
- HeapRegion* pop() {
- HeapRegion* res = RegionList::pop();
- if (res != NULL) res->set_on_unclean_list(false);
- return res;
- }
-};
-
-// Local Variables: ***
-// c-indentation-style: gnu ***
-// End: ***
-
#endif // SERIALGC
#endif // SHARE_VM_GC_IMPLEMENTATION_G1_HEAPREGION_HPP
--- a/hotspot/src/share/vm/gc_implementation/g1/heapRegionSeq.cpp Wed Jan 19 19:24:34 2011 -0800
+++ b/hotspot/src/share/vm/gc_implementation/g1/heapRegionSeq.cpp Thu Jan 20 13:57:12 2011 -0800
@@ -65,152 +65,6 @@
// Private methods.
-HeapWord*
-HeapRegionSeq::alloc_obj_from_region_index(int ind, size_t word_size) {
- assert(G1CollectedHeap::isHumongous(word_size),
- "Allocation size should be humongous");
- int cur = ind;
- int first = cur;
- size_t sumSizes = 0;
- while (cur < _regions.length() && sumSizes < word_size) {
- // Loop invariant:
- // For all i in [first, cur):
- // _regions.at(i)->is_empty()
- // && _regions.at(i) is contiguous with its predecessor, if any
- // && sumSizes is the sum of the sizes of the regions in the interval
- // [first, cur)
- HeapRegion* curhr = _regions.at(cur);
- if (curhr->is_empty()
- && (first == cur
- || (_regions.at(cur-1)->end() ==
- curhr->bottom()))) {
- sumSizes += curhr->capacity() / HeapWordSize;
- } else {
- first = cur + 1;
- sumSizes = 0;
- }
- cur++;
- }
- if (sumSizes >= word_size) {
- _alloc_search_start = cur;
-
- // We need to initialize the region(s) we just discovered. This is
- // a bit tricky given that it can happen concurrently with
- // refinement threads refining cards on these regions and
- // potentially wanting to refine the BOT as they are scanning
- // those cards (this can happen shortly after a cleanup; see CR
- // 6991377). So we have to set up the region(s) carefully and in
- // a specific order.
-
- // Currently, allocs_are_zero_filled() returns false. The zero
- // filling infrastructure will be going away soon (see CR 6977804).
- // So no need to do anything else here.
- bool zf = G1CollectedHeap::heap()->allocs_are_zero_filled();
- assert(!zf, "not supported");
-
- // This will be the "starts humongous" region.
- HeapRegion* first_hr = _regions.at(first);
- {
- MutexLockerEx x(ZF_mon, Mutex::_no_safepoint_check_flag);
- first_hr->set_zero_fill_allocated();
- }
- // The header of the new object will be placed at the bottom of
- // the first region.
- HeapWord* new_obj = first_hr->bottom();
- // This will be the new end of the first region in the series that
- // should also match the end of the last region in the seriers.
- // (Note: sumSizes = "region size" x "number of regions we found").
- HeapWord* new_end = new_obj + sumSizes;
- // This will be the new top of the first region that will reflect
- // this allocation.
- HeapWord* new_top = new_obj + word_size;
-
- // First, we need to zero the header of the space that we will be
- // allocating. When we update top further down, some refinement
- // threads might try to scan the region. By zeroing the header we
- // ensure that any thread that will try to scan the region will
- // come across the zero klass word and bail out.
- //
- // NOTE: It would not have been correct to have used
- // CollectedHeap::fill_with_object() and make the space look like
- // an int array. The thread that is doing the allocation will
- // later update the object header to a potentially different array
- // type and, for a very short period of time, the klass and length
- // fields will be inconsistent. This could cause a refinement
- // thread to calculate the object size incorrectly.
- Copy::fill_to_words(new_obj, oopDesc::header_size(), 0);
-
- // We will set up the first region as "starts humongous". This
- // will also update the BOT covering all the regions to reflect
- // that there is a single object that starts at the bottom of the
- // first region.
- first_hr->set_startsHumongous(new_top, new_end);
-
- // Then, if there are any, we will set up the "continues
- // humongous" regions.
- HeapRegion* hr = NULL;
- for (int i = first + 1; i < cur; ++i) {
- hr = _regions.at(i);
- {
- MutexLockerEx x(ZF_mon, Mutex::_no_safepoint_check_flag);
- hr->set_zero_fill_allocated();
- }
- hr->set_continuesHumongous(first_hr);
- }
- // If we have "continues humongous" regions (hr != NULL), then the
- // end of the last one should match new_end.
- assert(hr == NULL || hr->end() == new_end, "sanity");
-
- // Up to this point no concurrent thread would have been able to
- // do any scanning on any region in this series. All the top
- // fields still point to bottom, so the intersection between
- // [bottom,top] and [card_start,card_end] will be empty. Before we
- // update the top fields, we'll do a storestore to make sure that
- // no thread sees the update to top before the zeroing of the
- // object header and the BOT initialization.
- OrderAccess::storestore();
-
- // Now that the BOT and the object header have been initialized,
- // we can update top of the "starts humongous" region.
- assert(first_hr->bottom() < new_top && new_top <= first_hr->end(),
- "new_top should be in this region");
- first_hr->set_top(new_top);
-
- // Now, we will update the top fields of the "continues humongous"
- // regions. The reason we need to do this is that, otherwise,
- // these regions would look empty and this will confuse parts of
- // G1. For example, the code that looks for a consecutive number
- // of empty regions will consider them empty and try to
- // re-allocate them. We can extend is_empty() to also include
- // !continuesHumongous(), but it is easier to just update the top
- // fields here.
- hr = NULL;
- for (int i = first + 1; i < cur; ++i) {
- hr = _regions.at(i);
- if ((i + 1) == cur) {
- // last continues humongous region
- assert(hr->bottom() < new_top && new_top <= hr->end(),
- "new_top should fall on this region");
- hr->set_top(new_top);
- } else {
- // not last one
- assert(new_top > hr->end(), "new_top should be above this region");
- hr->set_top(hr->end());
- }
- }
- // If we have continues humongous regions (hr != NULL), then the
- // end of the last one should match new_end and its top should
- // match new_top.
- assert(hr == NULL ||
- (hr->end() == new_end && hr->top() == new_top), "sanity");
-
- return new_obj;
- } else {
- // If we started from the beginning, we want to know why we can't alloc.
- return NULL;
- }
-}
-
void HeapRegionSeq::print_empty_runs() {
int empty_run = 0;
int n_empty = 0;
@@ -284,13 +138,67 @@
return res;
}
-HeapWord* HeapRegionSeq::obj_allocate(size_t word_size) {
- int cur = _alloc_search_start;
- // Make sure "cur" is a valid index.
- assert(cur >= 0, "Invariant.");
- HeapWord* res = alloc_obj_from_region_index(cur, word_size);
- if (res == NULL)
- res = alloc_obj_from_region_index(0, word_size);
+int HeapRegionSeq::find_contiguous_from(int from, size_t num) {
+ assert(num > 1, "pre-condition");
+ assert(0 <= from && from <= _regions.length(),
+ err_msg("from: %d should be valid and <= than %d",
+ from, _regions.length()));
+
+ int curr = from;
+ int first = -1;
+ size_t num_so_far = 0;
+ while (curr < _regions.length() && num_so_far < num) {
+ HeapRegion* curr_hr = _regions.at(curr);
+ if (curr_hr->is_empty()) {
+ if (first == -1) {
+ first = curr;
+ num_so_far = 1;
+ } else {
+ num_so_far += 1;
+ }
+ } else {
+ first = -1;
+ num_so_far = 0;
+ }
+ curr += 1;
+ }
+
+ assert(num_so_far <= num, "post-condition");
+ if (num_so_far == num) {
+ // we find enough space for the humongous object
+ assert(from <= first && first < _regions.length(), "post-condition");
+ assert(first < curr && (curr - first) == (int) num, "post-condition");
+ for (int i = first; i < first + (int) num; ++i) {
+ assert(_regions.at(i)->is_empty(), "post-condition");
+ }
+ return first;
+ } else {
+ // we failed to find enough space for the humongous object
+ return -1;
+ }
+}
+
+int HeapRegionSeq::find_contiguous(size_t num) {
+ assert(num > 1, "otherwise we should not be calling this");
+ assert(0 <= _alloc_search_start && _alloc_search_start <= _regions.length(),
+ err_msg("_alloc_search_start: %d should be valid and <= than %d",
+ _alloc_search_start, _regions.length()));
+
+ int start = _alloc_search_start;
+ int res = find_contiguous_from(start, num);
+ if (res == -1 && start != 0) {
+ // Try starting from the beginning. If _alloc_search_start was 0,
+ // no point in doing this again.
+ res = find_contiguous_from(0, num);
+ }
+ if (res != -1) {
+ assert(0 <= res && res < _regions.length(),
+ err_msg("res: %d should be valid", res));
+ _alloc_search_start = res + (int) num;
+ }
+ assert(0 < _alloc_search_start && _alloc_search_start <= _regions.length(),
+ err_msg("_alloc_search_start: %d should be valid",
+ _alloc_search_start));
return res;
}
@@ -376,6 +284,10 @@
MemRegion HeapRegionSeq::shrink_by(size_t shrink_bytes,
size_t& num_regions_deleted) {
+ // Reset this in case it's currently pointing into the regions that
+ // we just removed.
+ _alloc_search_start = 0;
+
assert(shrink_bytes % os::vm_page_size() == 0, "unaligned");
assert(shrink_bytes % HeapRegion::GrainBytes == 0, "unaligned");
@@ -395,7 +307,6 @@
}
assert(cur == _regions.top(), "Should be top");
if (!cur->is_empty()) break;
- cur->reset_zero_fill();
shrink_bytes -= cur->capacity();
num_regions_deleted++;
_regions.pop();
@@ -410,7 +321,6 @@
return MemRegion(last_start, end);
}
-
class PrintHeapRegionClosure : public HeapRegionClosure {
public:
bool doHeapRegion(HeapRegion* r) {
--- a/hotspot/src/share/vm/gc_implementation/g1/heapRegionSeq.hpp Wed Jan 19 19:24:34 2011 -0800
+++ b/hotspot/src/share/vm/gc_implementation/g1/heapRegionSeq.hpp Thu Jan 20 13:57:12 2011 -0800
@@ -1,5 +1,5 @@
/*
- * Copyright (c) 2001, 2010, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2001, 2011, 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
@@ -41,9 +41,9 @@
// (For efficiency only; private to obj_allocate after initialization.)
int _alloc_search_start;
- // Attempts to allocate a block of the (assumed humongous) word_size,
- // starting at the region "ind".
- HeapWord* alloc_obj_from_region_index(int ind, size_t word_size);
+ // Finds a contiguous set of empty regions of length num, starting
+ // from a given index.
+ int find_contiguous_from(int from, size_t num);
// Currently, we're choosing collection sets in a round-robin fashion,
// starting here.
@@ -76,11 +76,8 @@
// that are available for allocation.
size_t free_suffix();
- // Requires "word_size" to be humongous (in the technical sense). If
- // possible, allocates a contiguous subsequence of the heap regions to
- // satisfy the allocation, and returns the address of the beginning of
- // that sequence, otherwise returns NULL.
- HeapWord* obj_allocate(size_t word_size);
+ // Finds a contiguous set of empty regions of length num.
+ int find_contiguous(size_t num);
// Apply the "doHeapRegion" method of "blk" to all regions in "this",
// in address order, terminating the iteration early
@@ -106,7 +103,7 @@
// If "addr" falls within a region in the sequence, return that region,
// or else NULL.
- HeapRegion* addr_to_region(const void* addr);
+ inline HeapRegion* addr_to_region(const void* addr);
void print();
--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/hotspot/src/share/vm/gc_implementation/g1/heapRegionSet.cpp Thu Jan 20 13:57:12 2011 -0800
@@ -0,0 +1,438 @@
+/*
+ * Copyright (c) 2011, 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
+ * 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 Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
+ * or visit www.oracle.com if you need additional information or have any
+ * questions.
+ *
+ */
+
+#include "precompiled.hpp"
+#include "gc_implementation/g1/heapRegionSet.inline.hpp"
+
+size_t HeapRegionSetBase::_unrealistically_long_length = 0;
+
+//////////////////// HeapRegionSetBase ////////////////////
+
+void HeapRegionSetBase::set_unrealistically_long_length(size_t len) {
+ guarantee(_unrealistically_long_length == 0, "should only be set once");
+ _unrealistically_long_length = len;
+}
+
+size_t HeapRegionSetBase::calculate_region_num(HeapRegion* hr) {
+ assert(hr->startsHumongous(), "pre-condition");
+ assert(hr->capacity() % HeapRegion::GrainBytes == 0, "invariant");
+ size_t region_num = hr->capacity() >> HeapRegion::LogOfHRGrainBytes;
+ assert(region_num > 0, "sanity");
+ return region_num;
+}
+
+void HeapRegionSetBase::fill_in_ext_msg(hrl_ext_msg* msg, const char* message) {
+ msg->append("[%s] %s "
+ "ln: "SIZE_FORMAT" rn: "SIZE_FORMAT" "
+ "cy: "SIZE_FORMAT" ud: "SIZE_FORMAT,
+ name(), message, length(), region_num(),
+ total_capacity_bytes(), total_used_bytes());
+ fill_in_ext_msg_extra(msg);
+}
+
+bool HeapRegionSetBase::verify_region(HeapRegion* hr,
+ HeapRegionSetBase* expected_containing_set) {
+ const char* error_message = NULL;
+
+ if (!regions_humongous()) {
+ if (hr->isHumongous()) {
+ error_message = "the region should not be humongous";
+ }
+ } else {
+ if (!hr->isHumongous() || !hr->startsHumongous()) {
+ error_message = "the region should be 'starts humongous'";
+ }
+ }
+
+ if (!regions_empty()) {
+ if (hr->is_empty()) {
+ error_message = "the region should not be empty";
+ }
+ } else {
+ if (!hr->is_empty()) {
+ error_message = "the region should be empty";
+ }
+ }
+
+#ifdef ASSERT
+ // The _containing_set field is only available when ASSERT is defined.
+ if (hr->containing_set() != expected_containing_set) {
+ error_message = "inconsistent containing set found";
+ }
+#endif // ASSERT
+
+ const char* extra_error_message = verify_region_extra(hr);
+ if (extra_error_message != NULL) {
+ error_message = extra_error_message;
+ }
+
+ if (error_message != NULL) {
+ outputStream* out = tty;
+ out->cr();
+ out->print_cr("## [%s] %s", name(), error_message);
+ out->print_cr("## Offending Region: "PTR_FORMAT, hr);
+ out->print_cr(" "HR_FORMAT, HR_FORMAT_PARAMS(hr));
+#ifdef ASSERT
+ out->print_cr(" containing set: "PTR_FORMAT, hr->containing_set());
+#endif // ASSERT
+ out->print_cr("## Offending Region Set: "PTR_FORMAT, this);
+ print_on(out);
+ return false;
+ } else {
+ return true;
+ }
+}
+
+void HeapRegionSetBase::verify() {
+ // It's important that we also observe the MT safety protocol even
+ // for the verification calls. If we do verification without the
+ // appropriate locks and the set changes underneath our feet
+ // verification might fail and send us on a wild goose chase.
+ hrl_assert_mt_safety_ok(this);
+
+ guarantee(( is_empty() && length() == 0 && region_num() == 0 &&
+ total_used_bytes() == 0 && total_capacity_bytes() == 0) ||
+ (!is_empty() && length() >= 0 && region_num() >= 0 &&
+ total_used_bytes() >= 0 && total_capacity_bytes() >= 0),
+ hrl_ext_msg(this, "invariant"));
+
+ guarantee((!regions_humongous() && region_num() == length()) ||
+ ( regions_humongous() && region_num() >= length()),
+ hrl_ext_msg(this, "invariant"));
+
+ guarantee(!regions_empty() || total_used_bytes() == 0,
+ hrl_ext_msg(this, "invariant"));
+
+ guarantee(total_used_bytes() <= total_capacity_bytes(),
+ hrl_ext_msg(this, "invariant"));
+}
+
+void HeapRegionSetBase::verify_start() {
+ // See comment in verify() about MT safety and verification.
+ hrl_assert_mt_safety_ok(this);
+ assert(!_verify_in_progress,
+ hrl_ext_msg(this, "verification should not be in progress"));
+
+ // Do the basic verification first before we do the checks over the regions.
+ HeapRegionSetBase::verify();
+
+ _calc_length = 0;
+ _calc_region_num = 0;
+ _calc_total_capacity_bytes = 0;
+ _calc_total_used_bytes = 0;
+ _verify_in_progress = true;
+}
+
+void HeapRegionSetBase::verify_next_region(HeapRegion* hr) {
+ // See comment in verify() about MT safety and verification.
+ hrl_assert_mt_safety_ok(this);
+ assert(_verify_in_progress,
+ hrl_ext_msg(this, "verification should be in progress"));
+
+ guarantee(verify_region(hr, this), hrl_ext_msg(this, "region verification"));
+
+ _calc_length += 1;
+ if (!hr->isHumongous()) {
+ _calc_region_num += 1;
+ } else {
+ _calc_region_num += calculate_region_num(hr);
+ }
+ _calc_total_capacity_bytes += hr->capacity();
+ _calc_total_used_bytes += hr->used();
+}
+
+void HeapRegionSetBase::verify_end() {
+ // See comment in verify() about MT safety and verification.
+ hrl_assert_mt_safety_ok(this);
+ assert(_verify_in_progress,
+ hrl_ext_msg(this, "verification should be in progress"));
+
+ guarantee(length() == _calc_length,
+ hrl_err_msg("[%s] length: "SIZE_FORMAT" should be == "
+ "calc length: "SIZE_FORMAT,
+ name(), length(), _calc_length));
+
+ guarantee(region_num() == _calc_region_num,
+ hrl_err_msg("[%s] region num: "SIZE_FORMAT" should be == "
+ "calc region num: "SIZE_FORMAT,
+ name(), region_num(), _calc_region_num));
+
+ guarantee(total_capacity_bytes() == _calc_total_capacity_bytes,
+ hrl_err_msg("[%s] capacity bytes: "SIZE_FORMAT" should be == "
+ "calc capacity bytes: "SIZE_FORMAT,
+ name(),
+ total_capacity_bytes(), _calc_total_capacity_bytes));
+
+ guarantee(total_used_bytes() == _calc_total_used_bytes,
+ hrl_err_msg("[%s] used bytes: "SIZE_FORMAT" should be == "
+ "calc used bytes: "SIZE_FORMAT,
+ name(), total_used_bytes(), _calc_total_used_bytes));
+
+ _verify_in_progress = false;
+}
+
+void HeapRegionSetBase::print_on(outputStream* out, bool print_contents) {
+ out->cr();
+ out->print_cr("Set: %s ("PTR_FORMAT")", name(), this);
+ out->print_cr(" Region Assumptions");
+ out->print_cr(" humongous : %s", BOOL_TO_STR(regions_humongous()));
+ out->print_cr(" empty : %s", BOOL_TO_STR(regions_empty()));
+ out->print_cr(" Attributes");
+ out->print_cr(" length : "SIZE_FORMAT_W(14), length());
+ out->print_cr(" region num : "SIZE_FORMAT_W(14), region_num());
+ out->print_cr(" total capacity : "SIZE_FORMAT_W(14)" bytes",
+ total_capacity_bytes());
+ out->print_cr(" total used : "SIZE_FORMAT_W(14)" bytes",
+ total_used_bytes());
+}
+
+void HeapRegionSetBase::clear() {
+ _length = 0;
+ _region_num = 0;
+ _total_used_bytes = 0;
+}
+
+HeapRegionSetBase::HeapRegionSetBase(const char* name)
+ : _name(name), _verify_in_progress(false),
+ _calc_length(0), _calc_region_num(0),
+ _calc_total_capacity_bytes(0), _calc_total_used_bytes(0) { }
+
+//////////////////// HeapRegionSet ////////////////////
+
+void HeapRegionSet::update_from_proxy(HeapRegionSet* proxy_set) {
+ hrl_assert_mt_safety_ok(this);
+ hrl_assert_mt_safety_ok(proxy_set);
+ hrl_assert_sets_match(this, proxy_set);
+
+ verify_optional();
+ proxy_set->verify_optional();
+
+ if (proxy_set->is_empty()) return;
+
+ assert(proxy_set->length() <= _length,
+ hrl_err_msg("[%s] proxy set length: "SIZE_FORMAT" "
+ "should be <= length: "SIZE_FORMAT,
+ name(), proxy_set->length(), _length));
+ _length -= proxy_set->length();
+
+ assert(proxy_set->region_num() <= _region_num,
+ hrl_err_msg("[%s] proxy set region num: "SIZE_FORMAT" "
+ "should be <= region num: "SIZE_FORMAT,
+ name(), proxy_set->region_num(), _region_num));
+ _region_num -= proxy_set->region_num();
+
+ assert(proxy_set->total_used_bytes() <= _total_used_bytes,
+ hrl_err_msg("[%s] proxy set used bytes: "SIZE_FORMAT" "
+ "should be <= used bytes: "SIZE_FORMAT,
+ name(), proxy_set->total_used_bytes(),
+ _total_used_bytes));
+ _total_used_bytes -= proxy_set->total_used_bytes();
+
+ proxy_set->clear();
+
+ verify_optional();
+ proxy_set->verify_optional();
+}
+
+//////////////////// HeapRegionLinkedList ////////////////////
+
+void HeapRegionLinkedList::fill_in_ext_msg_extra(hrl_ext_msg* msg) {
+ msg->append(" hd: "PTR_FORMAT" tl: "PTR_FORMAT, head(), tail());
+}
+
+void HeapRegionLinkedList::add_as_tail(HeapRegionLinkedList* from_list) {
+ hrl_assert_mt_safety_ok(this);
+ hrl_assert_mt_safety_ok(from_list);
+
+ verify_optional();
+ from_list->verify_optional();
+
+ if (from_list->is_empty()) return;
+
+#ifdef ASSERT
+ HeapRegionLinkedListIterator iter(from_list);
+ while (iter.more_available()) {
+ HeapRegion* hr = iter.get_next();
+ // In set_containing_set() we check that we either set the value
+ // from NULL to non-NULL or vice versa to catch bugs. So, we have
+ // to NULL it first before setting it to the value.
+ hr->set_containing_set(NULL);
+ hr->set_containing_set(this);
+ }
+#endif // ASSERT
+
+ if (_tail != NULL) {
+ assert(length() > 0 && _head != NULL, hrl_ext_msg(this, "invariant"));
+ _tail->set_next(from_list->_head);
+ } else {
+ assert(length() == 0 && _head == NULL, hrl_ext_msg(this, "invariant"));
+ _head = from_list->_head;
+ }
+ _tail = from_list->_tail;
+
+ _length += from_list->length();
+ _region_num += from_list->region_num();
+ _total_used_bytes += from_list->total_used_bytes();
+ from_list->clear();
+
+ verify_optional();
+ from_list->verify_optional();
+}
+
+void HeapRegionLinkedList::remove_all() {
+ hrl_assert_mt_safety_ok(this);
+ verify_optional();
+
+ HeapRegion* curr = _head;
+ while (curr != NULL) {
+ hrl_assert_region_ok(this, curr, this);
+
+ HeapRegion* next = curr->next();
+ curr->set_next(NULL);
+ curr->set_containing_set(NULL);
+ curr = next;
+ }
+ clear();
+
+ verify_optional();
+}
+
+void HeapRegionLinkedList::remove_all_pending(size_t target_count) {
+ hrl_assert_mt_safety_ok(this);
+ assert(target_count > 1, hrl_ext_msg(this, "pre-condition"));
+ assert(!is_empty(), hrl_ext_msg(this, "pre-condition"));
+
+ verify_optional();
+ DEBUG_ONLY(size_t old_length = length();)
+
+ HeapRegion* curr = _head;
+ HeapRegion* prev = NULL;
+ size_t count = 0;
+ while (curr != NULL) {
+ hrl_assert_region_ok(this, curr, this);
+ HeapRegion* next = curr->next();
+
+ if (curr->pending_removal()) {
+ assert(count < target_count,
+ hrl_err_msg("[%s] should not come across more regions "
+ "pending for removal than target_count: "SIZE_FORMAT,
+ name(), target_count));
+
+ if (prev == NULL) {
+ assert(_head == curr, hrl_ext_msg(this, "invariant"));
+ _head = next;
+ } else {
+ assert(_head != curr, hrl_ext_msg(this, "invariant"));
+ prev->set_next(next);
+ }
+ if (next == NULL) {
+ assert(_tail == curr, hrl_ext_msg(this, "invariant"));
+ _tail = prev;
+ } else {
+ assert(_tail != curr, hrl_ext_msg(this, "invariant"));
+ }
+
+ curr->set_next(NULL);
+ remove_internal(curr);
+ curr->set_pending_removal(false);
+
+ count += 1;
+
+ // If we have come across the target number of regions we can
+ // just bail out. However, for debugging purposes, we can just
+ // carry on iterating to make sure there are not more regions
+ // tagged with pending removal.
+ DEBUG_ONLY(if (count == target_count) break;)
+ } else {
+ prev = curr;
+ }
+ curr = next;
+ }
+
+ assert(count == target_count,
+ hrl_err_msg("[%s] count: "SIZE_FORMAT" should be == "
+ "target_count: "SIZE_FORMAT, name(), count, target_count));
+ assert(length() + target_count == old_length,
+ hrl_err_msg("[%s] new length should be consistent "
+ "new length: "SIZE_FORMAT" old length: "SIZE_FORMAT" "
+ "target_count: "SIZE_FORMAT,
+ name(), length(), old_length, target_count));
+
+ verify_optional();
+}
+
+void HeapRegionLinkedList::verify() {
+ // See comment in HeapRegionSetBase::verify() about MT safety and
+ // verification.
+ hrl_assert_mt_safety_ok(this);
+
+ // This will also do the basic verification too.
+ verify_start();
+
+ HeapRegion* curr = _head;
+ HeapRegion* prev1 = NULL;
+ HeapRegion* prev0 = NULL;
+ size_t count = 0;
+ while (curr != NULL) {
+ verify_next_region(curr);
+
+ count += 1;
+ guarantee(count < _unrealistically_long_length,
+ hrl_err_msg("[%s] the calculated length: "SIZE_FORMAT" "
+ "seems very long, is there maybe a cycle? "
+ "curr: "PTR_FORMAT" prev0: "PTR_FORMAT" "
+ "prev1: "PTR_FORMAT" length: "SIZE_FORMAT,
+ name(), count, curr, prev0, prev1, length()));
+
+ prev1 = prev0;
+ prev0 = curr;
+ curr = curr->next();
+ }
+
+ guarantee(_tail == prev0, hrl_ext_msg(this, "post-condition"));
+
+ verify_end();
+}
+
+void HeapRegionLinkedList::clear() {
+ HeapRegionSetBase::clear();
+ _head = NULL;
+ _tail = NULL;
+}
+
+void HeapRegionLinkedList::print_on(outputStream* out, bool print_contents) {
+ HeapRegionSetBase::print_on(out, print_contents);
+ out->print_cr(" Linking");
+ out->print_cr(" head : "PTR_FORMAT, _head);
+ out->print_cr(" tail : "PTR_FORMAT, _tail);
+
+ if (print_contents) {
+ out->print_cr(" Contents");
+ HeapRegionLinkedListIterator iter(this);
+ while (iter.more_available()) {
+ HeapRegion* hr = iter.get_next();
+ hr->print_on(out);
+ }
+ }
+}
--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/hotspot/src/share/vm/gc_implementation/g1/heapRegionSet.hpp Thu Jan 20 13:57:12 2011 -0800
@@ -0,0 +1,346 @@
+/*
+ * copyright (c) 2011, 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
+ * 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 Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
+ * or visit www.oracle.com if you need additional information or have any
+ * questions.
+ *
+ */
+
+#ifndef SHARE_VM_GC_IMPLEMENTATION_G1_HEAPREGIONSET_HPP
+#define SHARE_VM_GC_IMPLEMENTATION_G1_HEAPREGIONSET_HPP
+
+#include "gc_implementation/g1/heapRegion.hpp"
+
+// Large buffer for some cases where the output might be larger than normal.
+#define HRL_ERR_MSG_BUFSZ 512
+typedef FormatBuffer<HRL_ERR_MSG_BUFSZ> hrl_err_msg;
+
+// Set verification will be forced either if someone defines
+// HEAP_REGION_SET_FORCE_VERIFY to be 1, or in builds in which
+// asserts are compiled in.
+#ifndef HEAP_REGION_SET_FORCE_VERIFY
+#define HEAP_REGION_SET_FORCE_VERIFY defined(ASSERT)
+#endif // HEAP_REGION_SET_FORCE_VERIFY
+
+//////////////////// HeapRegionSetBase ////////////////////
+
+// Base class for all the classes that represent heap region sets. It
+// contains the basic attributes that each set needs to maintain
+// (e.g., length, region num, used bytes sum) plus any shared
+// functionality (e.g., verification).
+
+class hrl_ext_msg;
+
+class HeapRegionSetBase VALUE_OBJ_CLASS_SPEC {
+ friend class hrl_ext_msg;
+
+protected:
+ static size_t calculate_region_num(HeapRegion* hr);
+
+ static size_t _unrealistically_long_length;
+
+ // The number of regions added to the set. If the set contains
+ // only humongous regions, this reflects only 'starts humongous'
+ // regions and does not include 'continues humongous' ones.
+ size_t _length;
+
+ // The total number of regions represented by the set. If the set
+ // does not contain humongous regions, this should be the same as
+ // _length. If the set contains only humongous regions, this will
+ // include the 'continues humongous' regions.
+ size_t _region_num;
+
+ // We don't keep track of the total capacity explicitly, we instead
+ // recalculate it based on _region_num and the heap region size.
+
+ // The sum of used bytes in the all the regions in the set.
+ size_t _total_used_bytes;
+
+ const char* _name;
+
+ bool _verify_in_progress;
+ size_t _calc_length;
+ size_t _calc_region_num;
+ size_t _calc_total_capacity_bytes;
+ size_t _calc_total_used_bytes;
+
+ // verify_region() is used to ensure that the contents of a region
+ // added to / removed from a set are consistent. Different sets
+ // make different assumptions about the regions added to them. So
+ // each set can override verify_region_extra(), which is called
+ // from verify_region(), and do any extra verification it needs to
+ // perform in that.
+ virtual const char* verify_region_extra(HeapRegion* hr) { return NULL; }
+ bool verify_region(HeapRegion* hr,
+ HeapRegionSetBase* expected_containing_set);
+
+ // Indicates whether all regions in the set should be humongous or
+ // not. Only used during verification.
+ virtual bool regions_humongous() = 0;
+
+ // Indicates whether all regions in the set should be empty or
+ // not. Only used during verification.
+ virtual bool regions_empty() = 0;
+
+ // Subclasses can optionally override this to do MT safety protocol
+ // checks. It is called in an assert from all methods that perform
+ // updates on the set (and subclasses should also call it too).
+ virtual bool check_mt_safety() { return true; }
+
+ // fill_in_ext_msg() writes the the values of the set's attributes
+ // in the custom err_msg (hrl_ext_msg). fill_in_ext_msg_extra()
+ // allows subclasses to append further information.
+ virtual void fill_in_ext_msg_extra(hrl_ext_msg* msg) { }
+ void fill_in_ext_msg(hrl_ext_msg* msg, const char* message);
+
+ // It updates the fields of the set to reflect hr being added to
+ // the set.
+ inline void update_for_addition(HeapRegion* hr);
+
+ // It updates the fields of the set to reflect hr being added to
+ // the set and tags the region appropriately.
+ inline void add_internal(HeapRegion* hr);
+
+ // It updates the fields of the set to reflect hr being removed
+ // from the set.
+ inline void update_for_removal(HeapRegion* hr);
+
+ // It updates the fields of the set to reflect hr being removed
+ // from the set and tags the region appropriately.
+ inline void remove_internal(HeapRegion* hr);
+
+ // It clears all the fields of the sets. Note: it will not iterate
+ // over the set and remove regions from it. It assumes that the
+ // caller has already done so. It will literally just clear the fields.
+ virtual void clear();
+
+ HeapRegionSetBase(const char* name);
+
+public:
+ static void set_unrealistically_long_length(size_t len);
+
+ const char* name() { return _name; }
+
+ size_t length() { return _length; }
+
+ bool is_empty() { return _length == 0; }
+
+ size_t region_num() { return _region_num; }
+
+ size_t total_capacity_bytes() {
+ return region_num() << HeapRegion::LogOfHRGrainBytes;
+ }
+
+ size_t total_used_bytes() { return _total_used_bytes; }
+
+ virtual void verify();
+ void verify_start();
+ void verify_next_region(HeapRegion* hr);
+ void verify_end();
+
+#if HEAP_REGION_SET_FORCE_VERIFY
+ void verify_optional() {
+ verify();
+ }
+#else // HEAP_REGION_SET_FORCE_VERIFY
+ void verify_optional() { }
+#endif // HEAP_REGION_SET_FORCE_VERIFY
+
+ virtual void print_on(outputStream* out, bool print_contents = false);
+};
+
+// Customized err_msg for heap region sets. Apart from a
+// assert/guarantee-specific message it also prints out the values of
+// the fields of the associated set. This can be very helpful in
+// diagnosing failures.
+
+class hrl_ext_msg : public hrl_err_msg {
+public:
+ hrl_ext_msg(HeapRegionSetBase* set, const char* message) : hrl_err_msg("") {
+ set->fill_in_ext_msg(this, message);
+ }
+};
+
+// These two macros are provided for convenience, to keep the uses of
+// these two asserts a bit more concise.
+
+#define hrl_assert_mt_safety_ok(_set_) \
+ do { \
+ assert((_set_)->check_mt_safety(), hrl_ext_msg((_set_), "MT safety")); \
+ } while (0)
+
+#define hrl_assert_region_ok(_set_, _hr_, _expected_) \
+ do { \
+ assert((_set_)->verify_region((_hr_), (_expected_)), \
+ hrl_ext_msg((_set_), "region verification")); \
+ } while (0)
+
+//////////////////// HeapRegionSet ////////////////////
+
+#define hrl_assert_sets_match(_set1_, _set2_) \
+ do { \
+ assert(((_set1_)->regions_humongous() == \
+ (_set2_)->regions_humongous()) && \
+ ((_set1_)->regions_empty() == (_set2_)->regions_empty()), \
+ hrl_err_msg("the contents of set %s and set %s should match", \
+ (_set1_)->name(), (_set2_)->name())); \
+ } while (0)
+
+// This class represents heap region sets whose members are not
+// explicitly tracked. It's helpful to group regions using such sets
+// so that we can reason about all the region groups in the heap using
+// the same interface (namely, the HeapRegionSetBase API).
+
+class HeapRegionSet : public HeapRegionSetBase {
+protected:
+ virtual const char* verify_region_extra(HeapRegion* hr) {
+ if (hr->next() != NULL) {
+ return "next() should always be NULL as we do not link the regions";
+ }
+
+ return HeapRegionSetBase::verify_region_extra(hr);
+ }
+
+ HeapRegionSet(const char* name) : HeapRegionSetBase(name) {
+ clear();
+ }
+
+public:
+ // It adds hr to the set. The region should not be a member of
+ // another set.
+ inline void add(HeapRegion* hr);
+
+ // It removes hr from the set. The region should be a member of
+ // this set.
+ inline void remove(HeapRegion* hr);
+
+ // It removes a region from the set. Instead of updating the fields
+ // of the set to reflect this removal, it accumulates the updates
+ // in proxy_set. The idea is that proxy_set is thread-local to
+ // avoid multiple threads updating the fields of the set
+ // concurrently and having to synchronize. The method
+ // update_from_proxy() will update the fields of the set from the
+ // proxy_set.
+ inline void remove_with_proxy(HeapRegion* hr, HeapRegionSet* proxy_set);
+
+ // After multiple calls to remove_with_proxy() the updates to the
+ // fields of the set are accumulated in proxy_set. This call
+ // updates the fields of the set from proxy_set.
+ void update_from_proxy(HeapRegionSet* proxy_set);
+};
+
+//////////////////// HeapRegionLinkedList ////////////////////
+
+// A set that links all the regions added to it in a singly-linked
+// list. We should try to avoid doing operations that iterate over
+// such lists in performance critical paths. Typically we should
+// add / remove one region at a time or concatenate two lists. All
+// those operations are done in constant time.
+
+class HeapRegionLinkedListIterator;
+
+class HeapRegionLinkedList : public HeapRegionSetBase {
+ friend class HeapRegionLinkedListIterator;
+
+private:
+ HeapRegion* _head;
+ HeapRegion* _tail;
+
+ // These are provided for use by the friend classes.
+ HeapRegion* head() { return _head; }
+ HeapRegion* tail() { return _tail; }
+
+protected:
+ virtual void fill_in_ext_msg_extra(hrl_ext_msg* msg);
+
+ // See the comment for HeapRegionSetBase::clear()
+ virtual void clear();
+
+ HeapRegionLinkedList(const char* name) : HeapRegionSetBase(name) {
+ clear();
+ }
+
+public:
+ // It adds hr to the list as the new tail. The region should not be
+ // a member of another set.
+ inline void add_as_tail(HeapRegion* hr);
+
+ // It removes and returns the head of the list. It assumes that the
+ // list is not empty so it will return a non-NULL value.
+ inline HeapRegion* remove_head();
+
+ // Convenience method.
+ inline HeapRegion* remove_head_or_null();
+
+ // It moves the regions from from_list to this list and empties
+ // from_list. The new regions will appear in the same order as they
+ // were in from_list and be linked in the end of this list.
+ void add_as_tail(HeapRegionLinkedList* from_list);
+
+ // It empties the list by removing all regions from it.
+ void remove_all();
+
+ // It removes all regions in the list that are pending for removal
+ // (i.e., they have been tagged with "pending_removal"). The list
+ // must not be empty, target_count should reflect the exact number
+ // of regions that are pending for removal in the list, and
+ // target_count should be > 1 (currently, we never need to remove a
+ // single region using this).
+ void remove_all_pending(size_t target_count);
+
+ virtual void verify();
+
+ virtual void print_on(outputStream* out, bool print_contents = false);
+};
+
+//////////////////// HeapRegionLinkedList ////////////////////
+
+// Iterator class that provides a convenient way to iterator over the
+// regions in a HeapRegionLinkedList instance.
+
+class HeapRegionLinkedListIterator : public StackObj {
+private:
+ HeapRegionLinkedList* _list;
+ HeapRegion* _curr;
+
+public:
+ bool more_available() {
+ return _curr != NULL;
+ }
+
+ HeapRegion* get_next() {
+ assert(more_available(),
+ "get_next() should be called when more regions are available");
+
+ // If we are going to introduce a count in the iterator we should
+ // do the "cycle" check.
+
+ HeapRegion* hr = _curr;
+ assert(_list->verify_region(hr, _list), "region verification");
+ _curr = hr->next();
+ return hr;
+ }
+
+ HeapRegionLinkedListIterator(HeapRegionLinkedList* list)
+ : _curr(NULL), _list(list) {
+ _curr = list->head();
+ }
+};
+
+#endif // SHARE_VM_GC_IMPLEMENTATION_G1_HEAPREGIONSET_HPP
--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/hotspot/src/share/vm/gc_implementation/g1/heapRegionSet.inline.hpp Thu Jan 20 13:57:12 2011 -0800
@@ -0,0 +1,159 @@
+/*
+ * copyright (c) 2011, 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
+ * 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 Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
+ * or visit www.oracle.com if you need additional information or have any
+ * questions.
+ *
+ */
+
+#ifndef SHARE_VM_GC_IMPLEMENTATION_G1_HEAPREGIONSET_INLINE_HPP
+#define SHARE_VM_GC_IMPLEMENTATION_G1_HEAPREGIONSET_INLINE_HPP
+
+#include "gc_implementation/g1/heapRegionSet.hpp"
+
+//////////////////// HeapRegionSetBase ////////////////////
+
+inline void HeapRegionSetBase::update_for_addition(HeapRegion* hr) {
+ // Assumes the caller has already verified the region.
+
+ _length += 1;
+ if (!hr->isHumongous()) {
+ _region_num += 1;
+ } else {
+ _region_num += calculate_region_num(hr);
+ }
+ _total_used_bytes += hr->used();
+}
+
+inline void HeapRegionSetBase::add_internal(HeapRegion* hr) {
+ hrl_assert_region_ok(this, hr, NULL);
+ assert(hr->next() == NULL, hrl_ext_msg(this, "should not already be linked"));
+
+ update_for_addition(hr);
+ hr->set_containing_set(this);
+}
+
+inline void HeapRegionSetBase::update_for_removal(HeapRegion* hr) {
+ // Assumes the caller has already verified the region.
+ assert(_length > 0, hrl_ext_msg(this, "pre-condition"));
+ _length -= 1;
+
+ size_t region_num_diff;
+ if (!hr->isHumongous()) {
+ region_num_diff = 1;
+ } else {
+ region_num_diff = calculate_region_num(hr);
+ }
+ assert(region_num_diff <= _region_num,
+ hrl_err_msg("[%s] region's region num: "SIZE_FORMAT" "
+ "should be <= region num: "SIZE_FORMAT,
+ name(), region_num_diff, _region_num));
+ _region_num -= region_num_diff;
+
+ size_t used_bytes = hr->used();
+ assert(used_bytes <= _total_used_bytes,
+ hrl_err_msg("[%s] region's used bytes: "SIZE_FORMAT" "
+ "should be <= used bytes: "SIZE_FORMAT,
+ name(), used_bytes, _total_used_bytes));
+ _total_used_bytes -= used_bytes;
+}
+
+inline void HeapRegionSetBase::remove_internal(HeapRegion* hr) {
+ hrl_assert_region_ok(this, hr, this);
+ assert(hr->next() == NULL, hrl_ext_msg(this, "should already be unlinked"));
+
+ hr->set_containing_set(NULL);
+ update_for_removal(hr);
+}
+
+//////////////////// HeapRegionSet ////////////////////
+
+inline void HeapRegionSet::add(HeapRegion* hr) {
+ hrl_assert_mt_safety_ok(this);
+ // add_internal() will verify the region.
+ add_internal(hr);
+}
+
+inline void HeapRegionSet::remove(HeapRegion* hr) {
+ hrl_assert_mt_safety_ok(this);
+ // remove_internal() will verify the region.
+ remove_internal(hr);
+}
+
+inline void HeapRegionSet::remove_with_proxy(HeapRegion* hr,
+ HeapRegionSet* proxy_set) {
+ // No need to fo the MT safety check here given that this method
+ // does not update the contents of the set but instead accumulates
+ // the changes in proxy_set which is assumed to be thread-local.
+ hrl_assert_sets_match(this, proxy_set);
+ hrl_assert_region_ok(this, hr, this);
+
+ hr->set_containing_set(NULL);
+ proxy_set->update_for_addition(hr);
+}
+
+//////////////////// HeapRegionLinkedList ////////////////////
+
+inline void HeapRegionLinkedList::add_as_tail(HeapRegion* hr) {
+ hrl_assert_mt_safety_ok(this);
+ assert((length() == 0 && _head == NULL && _tail == NULL) ||
+ (length() > 0 && _head != NULL && _tail != NULL),
+ hrl_ext_msg(this, "invariant"));
+ // add_internal() will verify the region.
+ add_internal(hr);
+
+ // Now link the region.
+ if (_tail != NULL) {
+ _tail->set_next(hr);
+ } else {
+ _head = hr;
+ }
+ _tail = hr;
+}
+
+inline HeapRegion* HeapRegionLinkedList::remove_head() {
+ hrl_assert_mt_safety_ok(this);
+ assert(!is_empty(), hrl_ext_msg(this, "the list should not be empty"));
+ assert(length() > 0 && _head != NULL && _tail != NULL,
+ hrl_ext_msg(this, "invariant"));
+
+ // We need to unlink it first.
+ HeapRegion* hr = _head;
+ _head = hr->next();
+ if (_head == NULL) {
+ _tail = NULL;
+ }
+ hr->set_next(NULL);
+
+ // remove_internal() will verify the region.
+ remove_internal(hr);
+ return hr;
+}
+
+inline HeapRegion* HeapRegionLinkedList::remove_head_or_null() {
+ hrl_assert_mt_safety_ok(this);
+
+ if (!is_empty()) {
+ return remove_head();
+ } else {
+ return NULL;
+ }
+}
+
+#endif // SHARE_VM_GC_IMPLEMENTATION_G1_HEAPREGIONSET_INLINE_HPP
--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/hotspot/src/share/vm/gc_implementation/g1/heapRegionSets.cpp Thu Jan 20 13:57:12 2011 -0800
@@ -0,0 +1,102 @@
+/*
+ * Copyright (c) 2011, 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
+ * 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 Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
+ * or visit www.oracle.com if you need additional information or have any
+ * questions.
+ *
+ */
+
+#include "precompiled.hpp"
+#include "gc_implementation/g1/heapRegionSets.hpp"
+
+//////////////////// FreeRegionList ////////////////////
+
+const char* FreeRegionList::verify_region_extra(HeapRegion* hr) {
+ if (hr->is_young()) {
+ return "the region should not be young";
+ }
+ // The superclass will check that the region is empty and
+ // not-humongous.
+ return HeapRegionLinkedList::verify_region_extra(hr);
+}
+
+//////////////////// MasterFreeRegionList ////////////////////
+
+bool MasterFreeRegionList::check_mt_safety() {
+ // Master Free List MT safety protocol:
+ // (a) If we're at a safepoint, operations on the master free list
+ // should be invoked by either the VM thread (which will serialize
+ // them) or by the GC workers while holding the
+ // FreeList_lock.
+ // (b) If we're not at a safepoint, operations on the master free
+ // list should be invoked while holding the Heap_lock.
+
+ guarantee((SafepointSynchronize::is_at_safepoint() &&
+ (Thread::current()->is_VM_thread() ||
+ FreeList_lock->owned_by_self())) ||
+ (!SafepointSynchronize::is_at_safepoint() &&
+ Heap_lock->owned_by_self()),
+ hrl_ext_msg(this, "master free list MT safety protocol"));
+
+ return FreeRegionList::check_mt_safety();
+}
+
+//////////////////// SecondaryFreeRegionList ////////////////////
+
+bool SecondaryFreeRegionList::check_mt_safety() {
+ // Secondary Free List MT safety protocol:
+ // Operations on the secondary free list should always be invoked
+ // while holding the SecondaryFreeList_lock.
+
+ guarantee(SecondaryFreeList_lock->owned_by_self(),
+ hrl_ext_msg(this, "secondary free list MT safety protocol"));
+
+ return FreeRegionList::check_mt_safety();
+}
+
+//////////////////// HumongousRegionSet ////////////////////
+
+const char* HumongousRegionSet::verify_region_extra(HeapRegion* hr) {
+ if (hr->is_young()) {
+ return "the region should not be young";
+ }
+ // The superclass will check that the region is not empty and
+ // humongous.
+ return HeapRegionSet::verify_region_extra(hr);
+}
+
+//////////////////// HumongousRegionSet ////////////////////
+
+bool MasterHumongousRegionSet::check_mt_safety() {
+ // Master Humongous Set MT safety protocol:
+ // (a) If we're at a safepoint, operations on the master humongous
+ // set should be invoked by either the VM thread (which will
+ // serialize them) or by the GC workers while holding the
+ // OldSets_lock.
+ // (b) If we're not at a safepoint, operations on the master
+ // humongous set should be invoked while holding the Heap_lock.
+
+ guarantee((SafepointSynchronize::is_at_safepoint() &&
+ (Thread::current()->is_VM_thread() ||
+ OldSets_lock->owned_by_self())) ||
+ (!SafepointSynchronize::is_at_safepoint() &&
+ Heap_lock->owned_by_self()),
+ hrl_ext_msg(this, "master humongous set MT safety protocol"));
+ return HumongousRegionSet::check_mt_safety();
+}
--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/hotspot/src/share/vm/gc_implementation/g1/heapRegionSets.hpp Thu Jan 20 13:57:12 2011 -0800
@@ -0,0 +1,86 @@
+/*
+ * copyright (c) 2011, 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
+ * 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 Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
+ * or visit www.oracle.com if you need additional information or have any
+ * questions.
+ *
+ */
+
+#ifndef SHARE_VM_GC_IMPLEMENTATION_G1_HEAPREGIONSETS_HPP
+#define SHARE_VM_GC_IMPLEMENTATION_G1_HEAPREGIONSETS_HPP
+
+#include "gc_implementation/g1/heapRegionSet.inline.hpp"
+
+//////////////////// FreeRegionList ////////////////////
+
+class FreeRegionList : public HeapRegionLinkedList {
+protected:
+ virtual const char* verify_region_extra(HeapRegion* hr);
+
+ virtual bool regions_humongous() { return false; }
+ virtual bool regions_empty() { return true; }
+
+public:
+ FreeRegionList(const char* name) : HeapRegionLinkedList(name) { }
+};
+
+//////////////////// MasterFreeRegionList ////////////////////
+
+class MasterFreeRegionList : public FreeRegionList {
+protected:
+ virtual bool check_mt_safety();
+
+public:
+ MasterFreeRegionList(const char* name) : FreeRegionList(name) { }
+};
+
+//////////////////// SecondaryFreeRegionList ////////////////////
+
+class SecondaryFreeRegionList : public FreeRegionList {
+protected:
+ virtual bool check_mt_safety();
+
+public:
+ SecondaryFreeRegionList(const char* name) : FreeRegionList(name) { }
+};
+
+//////////////////// HumongousRegionSet ////////////////////
+
+class HumongousRegionSet : public HeapRegionSet {
+protected:
+ virtual const char* verify_region_extra(HeapRegion* hr);
+
+ virtual bool regions_humongous() { return true; }
+ virtual bool regions_empty() { return false; }
+
+public:
+ HumongousRegionSet(const char* name) : HeapRegionSet(name) { }
+};
+
+//////////////////// MasterHumongousRegionSet ////////////////////
+
+class MasterHumongousRegionSet : public HumongousRegionSet {
+protected:
+ virtual bool check_mt_safety();
+
+public:
+ MasterHumongousRegionSet(const char* name) : HumongousRegionSet(name) { }
+};
+
+#endif // SHARE_VM_GC_IMPLEMENTATION_G1_HEAPREGIONSETS_HPP
--- a/hotspot/src/share/vm/gc_implementation/g1/ptrQueue.cpp Wed Jan 19 19:24:34 2011 -0800
+++ b/hotspot/src/share/vm/gc_implementation/g1/ptrQueue.cpp Thu Jan 20 13:57:12 2011 -0800
@@ -1,5 +1,5 @@
/*
- * Copyright (c) 2001, 2010, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2001, 2011, 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
@@ -38,8 +38,8 @@
# include "thread_windows.inline.hpp"
#endif
-PtrQueue::PtrQueue(PtrQueueSet* qset_, bool perm, bool active) :
- _qset(qset_), _buf(NULL), _index(0), _active(active),
+PtrQueue::PtrQueue(PtrQueueSet* qset, bool perm, bool active) :
+ _qset(qset), _buf(NULL), _index(0), _active(active),
_perm(perm), _lock(NULL)
{}
@@ -153,10 +153,16 @@
}
void PtrQueue::handle_zero_index() {
- assert(0 == _index, "Precondition.");
+ assert(_index == 0, "Precondition.");
+
// This thread records the full buffer and allocates a new one (while
// holding the lock if there is one).
if (_buf != NULL) {
+ if (!should_enqueue_buffer()) {
+ assert(_index > 0, "the buffer can only be re-used if it's not full");
+ return;
+ }
+
if (_lock) {
assert(_lock->owned_by_self(), "Required.");
--- a/hotspot/src/share/vm/gc_implementation/g1/ptrQueue.hpp Wed Jan 19 19:24:34 2011 -0800
+++ b/hotspot/src/share/vm/gc_implementation/g1/ptrQueue.hpp Thu Jan 20 13:57:12 2011 -0800
@@ -1,5 +1,5 @@
/*
- * Copyright (c) 2001, 2010, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2001, 2011, 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
@@ -68,7 +68,7 @@
public:
// Initialize this queue to contain a null buffer, and be part of the
// given PtrQueueSet.
- PtrQueue(PtrQueueSet*, bool perm = false, bool active = false);
+ PtrQueue(PtrQueueSet* qset, bool perm = false, bool active = false);
// Release any contained resources.
void flush();
// Calls flush() when destroyed.
@@ -85,6 +85,14 @@
else enqueue_known_active(ptr);
}
+ // This method is called when we're doing the zero index handling
+ // and gives a chance to the queues to do any pre-enqueueing
+ // processing they might want to do on the buffer. It should return
+ // true if the buffer should be enqueued, or false if enough
+ // entries were cleared from it so that it can be re-used. It should
+ // not return false if the buffer is still full (otherwise we can
+ // get into an infinite loop).
+ virtual bool should_enqueue_buffer() { return true; }
void handle_zero_index();
void locking_enqueue_completed_buffer(void** buf);
--- a/hotspot/src/share/vm/gc_implementation/g1/satbQueue.cpp Wed Jan 19 19:24:34 2011 -0800
+++ b/hotspot/src/share/vm/gc_implementation/g1/satbQueue.cpp Thu Jan 20 13:57:12 2011 -0800
@@ -1,5 +1,5 @@
/*
- * Copyright (c) 2001, 2010, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2001, 2011, 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
@@ -23,12 +23,98 @@
*/
#include "precompiled.hpp"
+#include "gc_implementation/g1/g1CollectedHeap.inline.hpp"
#include "gc_implementation/g1/satbQueue.hpp"
#include "memory/allocation.inline.hpp"
#include "memory/sharedHeap.hpp"
#include "runtime/mutexLocker.hpp"
#include "runtime/thread.hpp"
+// This method removes entries from an SATB buffer that will not be
+// useful to the concurrent marking threads. An entry is removed if it
+// satisfies one of the following conditions:
+//
+// * it points to an object outside the G1 heap (G1's concurrent
+// marking only visits objects inside the G1 heap),
+// * it points to an object that has been allocated since marking
+// started (according to SATB those objects do not need to be
+// visited during marking), or
+// * it points to an object that has already been marked (no need to
+// process it again).
+//
+// The rest of the entries will be retained and are compacted towards
+// the top of the buffer. If with this filtering we clear a large
+// enough chunk of the buffer we can re-use it (instead of enqueueing
+// it) and we can just allow the mutator to carry on executing.
+
+bool ObjPtrQueue::should_enqueue_buffer() {
+ assert(_lock == NULL || _lock->owned_by_self(),
+ "we should have taken the lock before calling this");
+
+ // A value of 0 means "don't filter SATB buffers".
+ if (G1SATBBufferEnqueueingThresholdPercent == 0) {
+ return true;
+ }
+
+ G1CollectedHeap* g1h = G1CollectedHeap::heap();
+
+ // This method should only be called if there is a non-NULL buffer
+ // that is full.
+ assert(_index == 0, "pre-condition");
+ assert(_buf != NULL, "pre-condition");
+
+ void** buf = _buf;
+ size_t sz = _sz;
+
+ // Used for sanity checking at the end of the loop.
+ debug_only(size_t entries = 0; size_t retained = 0;)
+
+ size_t i = sz;
+ size_t new_index = sz;
+
+ // Given that we are expecting _index == 0, we could have changed
+ // the loop condition to (i > 0). But we are using _index for
+ // generality.
+ while (i > _index) {
+ assert(i > 0, "we should have at least one more entry to process");
+ i -= oopSize;
+ debug_only(entries += 1;)
+ oop* p = (oop*) &buf[byte_index_to_index((int) i)];
+ oop obj = *p;
+ // NULL the entry so that unused parts of the buffer contain NULLs
+ // at the end. If we are going to retain it we will copy it to its
+ // final place. If we have retained all entries we have visited so
+ // far, we'll just end up copying it to the same place.
+ *p = NULL;
+
+ bool retain = g1h->is_obj_ill(obj);
+ if (retain) {
+ assert(new_index > 0, "we should not have already filled up the buffer");
+ new_index -= oopSize;
+ assert(new_index >= i,
+ "new_index should never be below i, as we alwaysr compact 'up'");
+ oop* new_p = (oop*) &buf[byte_index_to_index((int) new_index)];
+ assert(new_p >= p, "the destination location should never be below "
+ "the source as we always compact 'up'");
+ assert(*new_p == NULL,
+ "we should have already cleared the destination location");
+ *new_p = obj;
+ debug_only(retained += 1;)
+ }
+ }
+ size_t entries_calc = (sz - _index) / oopSize;
+ assert(entries == entries_calc, "the number of entries we counted "
+ "should match the number of entries we calculated");
+ size_t retained_calc = (sz - new_index) / oopSize;
+ assert(retained == retained_calc, "the number of retained entries we counted "
+ "should match the number of retained entries we calculated");
+ size_t perc = retained_calc * 100 / entries_calc;
+ bool should_enqueue = perc > (size_t) G1SATBBufferEnqueueingThresholdPercent;
+ _index = new_index;
+
+ return should_enqueue;
+}
+
void ObjPtrQueue::apply_closure(ObjectClosure* cl) {
if (_buf != NULL) {
apply_closure_to_buffer(cl, _buf, _index, _sz);
--- a/hotspot/src/share/vm/gc_implementation/g1/satbQueue.hpp Wed Jan 19 19:24:34 2011 -0800
+++ b/hotspot/src/share/vm/gc_implementation/g1/satbQueue.hpp Thu Jan 20 13:57:12 2011 -0800
@@ -1,5 +1,5 @@
/*
- * Copyright (c) 2001, 2010, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2001, 2011, 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
@@ -33,13 +33,18 @@
// A ptrQueue whose elements are "oops", pointers to object heads.
class ObjPtrQueue: public PtrQueue {
public:
- ObjPtrQueue(PtrQueueSet* qset_, bool perm = false) :
+ ObjPtrQueue(PtrQueueSet* qset, bool perm = false) :
// 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 */) { }
+ PtrQueue(qset, perm, false /* active */) { }
+
+ // Overrides PtrQueue::should_enqueue_buffer(). See the method's
+ // definition for more information.
+ virtual bool should_enqueue_buffer();
+
// 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/runtime/mutexLocker.cpp Wed Jan 19 19:24:34 2011 -0800
+++ b/hotspot/src/share/vm/runtime/mutexLocker.cpp Thu Jan 20 13:57:12 2011 -0800
@@ -1,5 +1,5 @@
/*
- * Copyright (c) 1997, 2010, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 1997, 2011, 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
@@ -80,8 +80,6 @@
Monitor* iCMS_lock = NULL;
Monitor* FullGCCount_lock = NULL;
Monitor* CMark_lock = NULL;
-Monitor* ZF_mon = NULL;
-Monitor* Cleanup_mon = NULL;
Mutex* CMRegionStack_lock = NULL;
Mutex* SATB_Q_FL_lock = NULL;
Monitor* SATB_Q_CBL_mon = NULL;
@@ -122,6 +120,9 @@
Mutex* PerfDataManager_lock = NULL;
Mutex* OopMapCacheAlloc_lock = NULL;
+Mutex* FreeList_lock = NULL;
+Monitor* SecondaryFreeList_lock = NULL;
+Mutex* OldSets_lock = NULL;
Mutex* MMUTracker_lock = NULL;
Mutex* HotCardCache_lock = NULL;
@@ -177,8 +178,6 @@
}
if (UseG1GC) {
def(CMark_lock , Monitor, nonleaf, true ); // coordinate concurrent mark thread
- def(ZF_mon , Monitor, leaf, true );
- def(Cleanup_mon , Monitor, nonleaf, true );
def(CMRegionStack_lock , Mutex, leaf, true );
def(SATB_Q_FL_lock , Mutex , special, true );
def(SATB_Q_CBL_mon , Monitor, nonleaf, true );
@@ -188,6 +187,9 @@
def(DirtyCardQ_CBL_mon , Monitor, nonleaf, true );
def(Shared_DirtyCardQ_lock , Mutex, nonleaf, true );
+ def(FreeList_lock , Mutex, leaf , true );
+ def(SecondaryFreeList_lock , Monitor, leaf , true );
+ def(OldSets_lock , Mutex , leaf , true );
def(MMUTracker_lock , Mutex , leaf , true );
def(HotCardCache_lock , Mutex , special , true );
def(EvacFailureStack_lock , Mutex , nonleaf , true );
--- a/hotspot/src/share/vm/runtime/mutexLocker.hpp Wed Jan 19 19:24:34 2011 -0800
+++ b/hotspot/src/share/vm/runtime/mutexLocker.hpp Thu Jan 20 13:57:12 2011 -0800
@@ -1,5 +1,5 @@
/*
- * Copyright (c) 1997, 2010, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 1997, 2011, 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
@@ -76,8 +76,6 @@
extern Monitor* iCMS_lock; // CMS incremental mode start/stop notification
extern Monitor* FullGCCount_lock; // in support of "concurrent" full gc
extern Monitor* CMark_lock; // used for concurrent mark thread coordination
-extern Monitor* ZF_mon; // used for G1 conc zero-fill.
-extern Monitor* Cleanup_mon; // used for G1 conc cleanup.
extern Mutex* CMRegionStack_lock; // used for protecting accesses to the CM region stack
extern Mutex* SATB_Q_FL_lock; // Protects SATB Q
// buffer free list.
@@ -125,6 +123,9 @@
extern Mutex* ParkerFreeList_lock;
extern Mutex* OopMapCacheAlloc_lock; // protects allocation of oop_map caches
+extern Mutex* FreeList_lock; // protects the free region list during safepoints
+extern Monitor* SecondaryFreeList_lock; // protects the secondary free region list
+extern Mutex* OldSets_lock; // protects the old region sets
extern Mutex* MMUTracker_lock; // protects the MMU
// tracker data structures
extern Mutex* HotCardCache_lock; // protects the hot card cache
--- a/hotspot/src/share/vm/utilities/debug.hpp Wed Jan 19 19:24:34 2011 -0800
+++ b/hotspot/src/share/vm/utilities/debug.hpp Thu Jan 20 13:57:12 2011 -0800
@@ -34,6 +34,7 @@
class FormatBuffer {
public:
inline FormatBuffer(const char * format, ...);
+ inline void append(const char* format, ...);
operator const char *() const { return _buf; }
private:
@@ -51,6 +52,19 @@
va_end(argp);
}
+template <size_t bufsz>
+void FormatBuffer<bufsz>::append(const char* format, ...) {
+ // Given that the constructor does a vsnprintf we can assume that
+ // _buf is already initialized.
+ size_t len = strlen(_buf);
+ char* buf_end = _buf + len;
+
+ va_list argp;
+ va_start(argp, format);
+ vsnprintf(buf_end, bufsz - len, format, argp);
+ va_end(argp);
+}
+
// Used to format messages for assert(), guarantee(), fatal(), etc.
typedef FormatBuffer<> err_msg;
--- a/hotspot/src/share/vm/utilities/globalDefinitions.hpp Wed Jan 19 19:24:34 2011 -0800
+++ b/hotspot/src/share/vm/utilities/globalDefinitions.hpp Thu Jan 20 13:57:12 2011 -0800
@@ -1,5 +1,5 @@
/*
- * Copyright (c) 1997, 2010, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 1997, 2011, 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
@@ -1179,6 +1179,8 @@
// '%d' formats to indicate a 64-bit quantity; commonly "l" (in LP64) or "ll"
// (in ILP32).
+#define BOOL_TO_STR(__b) (__b) ? "true" : "false"
+
// Format 32-bit quantities.
#define INT32_FORMAT "%d"
#define UINT32_FORMAT "%u"