duke@435: /*
sla@5237:  * Copyright (c) 2002, 2013, Oracle and/or its affiliates. All rights reserved.
duke@435:  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
duke@435:  *
duke@435:  * This code is free software; you can redistribute it and/or modify it
duke@435:  * under the terms of the GNU General Public License version 2 only, as
duke@435:  * published by the Free Software Foundation.
duke@435:  *
duke@435:  * This code is distributed in the hope that it will be useful, but WITHOUT
duke@435:  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
duke@435:  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
duke@435:  * version 2 for more details (a copy is included in the LICENSE file that
duke@435:  * accompanied this code).
duke@435:  *
duke@435:  * You should have received a copy of the GNU General Public License version
duke@435:  * 2 along with this work; if not, write to the Free Software Foundation,
duke@435:  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
duke@435:  *
trims@1907:  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
trims@1907:  * or visit www.oracle.com if you need additional information or have any
trims@1907:  * questions.
duke@435:  *
duke@435:  */
duke@435: 
stefank@2314: #include "precompiled.hpp"
stefank@2314: #include "gc_implementation/parallelScavenge/parallelScavengeHeap.hpp"
stefank@2314: #include "gc_implementation/parallelScavenge/psOldGen.hpp"
stefank@2314: #include "gc_implementation/parallelScavenge/psPromotionManager.inline.hpp"
stefank@2314: #include "gc_implementation/parallelScavenge/psScavenge.inline.hpp"
sla@5237: #include "gc_implementation/shared/gcTrace.hpp"
stefank@2314: #include "gc_implementation/shared/mutableSpace.hpp"
stefank@5515: #include "memory/allocation.inline.hpp"
stefank@2314: #include "memory/memRegion.hpp"
stefank@5515: #include "memory/padded.inline.hpp"
stefank@2314: #include "oops/oop.inline.hpp"
stefank@2314: #include "oops/oop.psgc.inline.hpp"
duke@435: 
stefank@5515: PaddedEnd<PSPromotionManager>* PSPromotionManager::_manager_array = NULL;
stefank@5515: OopStarTaskQueueSet*           PSPromotionManager::_stack_array_depth = NULL;
stefank@5515: PSOldGen*                      PSPromotionManager::_old_gen = NULL;
stefank@5515: MutableSpace*                  PSPromotionManager::_young_space = NULL;
duke@435: 
duke@435: void PSPromotionManager::initialize() {
duke@435:   ParallelScavengeHeap* heap = (ParallelScavengeHeap*)Universe::heap();
duke@435:   assert(heap->kind() == CollectedHeap::ParallelScavengeHeap, "Sanity");
duke@435: 
duke@435:   _old_gen = heap->old_gen();
duke@435:   _young_space = heap->young_gen()->to_space();
duke@435: 
stefank@5515:   // To prevent false sharing, we pad the PSPromotionManagers
stefank@5515:   // and make sure that the first instance starts at a cache line.
duke@435:   assert(_manager_array == NULL, "Attempt to initialize twice");
stefank@5515:   _manager_array = PaddedArray<PSPromotionManager, mtGC>::create_unfreeable(ParallelGCThreads + 1);
duke@435:   guarantee(_manager_array != NULL, "Could not initialize promotion manager");
duke@435: 
tonyp@2061:   _stack_array_depth = new OopStarTaskQueueSet(ParallelGCThreads);
sla@5237:   guarantee(_stack_array_depth != NULL, "Could not initialize promotion manager");
duke@435: 
duke@435:   // Create and register the PSPromotionManager(s) for the worker threads.
duke@435:   for(uint i=0; i<ParallelGCThreads; i++) {
stefank@5515:     stack_array_depth()->register_queue(i, _manager_array[i].claimed_stack_depth());
duke@435:   }
duke@435:   // The VMThread gets its own PSPromotionManager, which is not available
duke@435:   // for work stealing.
duke@435: }
duke@435: 
duke@435: PSPromotionManager* PSPromotionManager::gc_thread_promotion_manager(int index) {
duke@435:   assert(index >= 0 && index < (int)ParallelGCThreads, "index out of range");
duke@435:   assert(_manager_array != NULL, "Sanity");
stefank@5515:   return &_manager_array[index];
duke@435: }
duke@435: 
duke@435: PSPromotionManager* PSPromotionManager::vm_thread_promotion_manager() {
duke@435:   assert(_manager_array != NULL, "Sanity");
stefank@5515:   return &_manager_array[ParallelGCThreads];
duke@435: }
duke@435: 
duke@435: void PSPromotionManager::pre_scavenge() {
duke@435:   ParallelScavengeHeap* heap = (ParallelScavengeHeap*)Universe::heap();
duke@435:   assert(heap->kind() == CollectedHeap::ParallelScavengeHeap, "Sanity");
duke@435: 
duke@435:   _young_space = heap->young_gen()->to_space();
duke@435: 
duke@435:   for(uint i=0; i<ParallelGCThreads+1; i++) {
duke@435:     manager_array(i)->reset();
duke@435:   }
duke@435: }
duke@435: 
sla@5237: bool PSPromotionManager::post_scavenge(YoungGCTracer& gc_tracer) {
sla@5237:   bool promotion_failure_occurred = false;
sla@5237: 
jcoomes@2020:   TASKQUEUE_STATS_ONLY(if (PrintGCDetails && ParallelGCVerbose) print_stats());
jcoomes@1993:   for (uint i = 0; i < ParallelGCThreads + 1; i++) {
duke@435:     PSPromotionManager* manager = manager_array(i);
tonyp@2061:     assert(manager->claimed_stack_depth()->is_empty(), "should be empty");
sla@5237:     if (manager->_promotion_failed_info.has_failed()) {
sla@5237:       gc_tracer.report_promotion_failed(manager->_promotion_failed_info);
sla@5237:       promotion_failure_occurred = true;
sla@5237:     }
duke@435:     manager->flush_labs();
duke@435:   }
sla@5237:   return promotion_failure_occurred;
duke@435: }
duke@435: 
jcoomes@2020: #if TASKQUEUE_STATS
duke@435: void
jcoomes@2020: PSPromotionManager::print_taskqueue_stats(uint i) const {
jcoomes@2020:   tty->print("%3u ", i);
tonyp@2061:   _claimed_stack_depth.stats.print();
jcoomes@2020:   tty->cr();
duke@435: }
duke@435: 
duke@435: void
jcoomes@2020: PSPromotionManager::print_local_stats(uint i) const {
jcoomes@2020:   #define FMT " " SIZE_FORMAT_W(10)
jcoomes@2020:   tty->print_cr("%3u" FMT FMT FMT FMT, i, _masked_pushes, _masked_steals,
jcoomes@2020:                 _arrays_chunked, _array_chunks_processed);
jcoomes@2020:   #undef FMT
jcoomes@2020: }
jcoomes@2020: 
jcoomes@2020: static const char* const pm_stats_hdr[] = {
jcoomes@2020:   "    --------masked-------     arrays      array",
jcoomes@2020:   "thr       push      steal    chunked     chunks",
jcoomes@2020:   "--- ---------- ---------- ---------- ----------"
jcoomes@2020: };
jcoomes@2020: 
jcoomes@2020: void
duke@435: PSPromotionManager::print_stats() {
tonyp@2061:   tty->print_cr("== GC Tasks Stats, GC %3d",
duke@435:                 Universe::heap()->total_collections());
duke@435: 
jcoomes@2020:   tty->print("thr "); TaskQueueStats::print_header(1); tty->cr();
jcoomes@2020:   tty->print("--- "); TaskQueueStats::print_header(2); tty->cr();
jcoomes@2020:   for (uint i = 0; i < ParallelGCThreads + 1; ++i) {
jcoomes@2020:     manager_array(i)->print_taskqueue_stats(i);
jcoomes@2020:   }
jcoomes@2020: 
jcoomes@2020:   const uint hlines = sizeof(pm_stats_hdr) / sizeof(pm_stats_hdr[0]);
jcoomes@2020:   for (uint i = 0; i < hlines; ++i) tty->print_cr(pm_stats_hdr[i]);
jcoomes@2020:   for (uint i = 0; i < ParallelGCThreads + 1; ++i) {
jcoomes@2020:     manager_array(i)->print_local_stats(i);
duke@435:   }
duke@435: }
duke@435: 
jcoomes@2020: void
jcoomes@2020: PSPromotionManager::reset_stats() {
tonyp@2061:   claimed_stack_depth()->stats.reset();
jcoomes@2020:   _masked_pushes = _masked_steals = 0;
jcoomes@2020:   _arrays_chunked = _array_chunks_processed = 0;
jcoomes@2020: }
jcoomes@2020: #endif // TASKQUEUE_STATS
duke@435: 
duke@435: PSPromotionManager::PSPromotionManager() {
duke@435:   ParallelScavengeHeap* heap = (ParallelScavengeHeap*)Universe::heap();
duke@435:   assert(heap->kind() == CollectedHeap::ParallelScavengeHeap, "Sanity");
duke@435: 
duke@435:   // We set the old lab's start array.
duke@435:   _old_lab.set_start_array(old_gen()->start_array());
duke@435: 
duke@435:   uint queue_size;
tonyp@2061:   claimed_stack_depth()->initialize();
tonyp@2061:   queue_size = claimed_stack_depth()->max_elems();
duke@435: 
duke@435:   _totally_drain = (ParallelGCThreads == 1) || (GCDrainStackTargetSize == 0);
duke@435:   if (_totally_drain) {
duke@435:     _target_stack_size = 0;
duke@435:   } else {
duke@435:     // don't let the target stack size to be more than 1/4 of the entries
duke@435:     _target_stack_size = (uint) MIN2((uint) GCDrainStackTargetSize,
duke@435:                                      (uint) (queue_size / 4));
duke@435:   }
duke@435: 
duke@435:   _array_chunk_size = ParGCArrayScanChunk;
duke@435:   // let's choose 1.5x the chunk size
duke@435:   _min_array_size_for_chunking = 3 * _array_chunk_size / 2;
duke@435: 
duke@435:   reset();
duke@435: }
duke@435: 
duke@435: void PSPromotionManager::reset() {
jcoomes@1993:   assert(stacks_empty(), "reset of non-empty stack");
duke@435: 
duke@435:   // We need to get an assert in here to make sure the labs are always flushed.
duke@435: 
duke@435:   ParallelScavengeHeap* heap = (ParallelScavengeHeap*)Universe::heap();
duke@435:   assert(heap->kind() == CollectedHeap::ParallelScavengeHeap, "Sanity");
duke@435: 
duke@435:   // Do not prefill the LAB's, save heap wastage!
duke@435:   HeapWord* lab_base = young_space()->top();
duke@435:   _young_lab.initialize(MemRegion(lab_base, (size_t)0));
duke@435:   _young_gen_is_full = false;
duke@435: 
duke@435:   lab_base = old_gen()->object_space()->top();
duke@435:   _old_lab.initialize(MemRegion(lab_base, (size_t)0));
duke@435:   _old_gen_is_full = false;
duke@435: 
sla@5237:   _promotion_failed_info.reset();
sla@5237: 
jcoomes@2020:   TASKQUEUE_STATS_ONLY(reset_stats());
duke@435: }
duke@435: 
coleenp@548: 
duke@435: void PSPromotionManager::drain_stacks_depth(bool totally_drain) {
duke@435:   totally_drain = totally_drain || _totally_drain;
duke@435: 
duke@435: #ifdef ASSERT
duke@435:   ParallelScavengeHeap* heap = (ParallelScavengeHeap*)Universe::heap();
duke@435:   assert(heap->kind() == CollectedHeap::ParallelScavengeHeap, "Sanity");
duke@435:   MutableSpace* to_space = heap->young_gen()->to_space();
duke@435:   MutableSpace* old_space = heap->old_gen()->object_space();
duke@435: #endif /* ASSERT */
duke@435: 
jcoomes@1993:   OopStarTaskQueue* const tq = claimed_stack_depth();
duke@435:   do {
coleenp@548:     StarTask p;
duke@435: 
duke@435:     // Drain overflow stack first, so other threads can steal from
duke@435:     // claimed stack while we work.
jcoomes@1993:     while (tq->pop_overflow(p)) {
jcoomes@1993:       process_popped_location_depth(p);
duke@435:     }
duke@435: 
duke@435:     if (totally_drain) {
jcoomes@1993:       while (tq->pop_local(p)) {
duke@435:         process_popped_location_depth(p);
duke@435:       }
duke@435:     } else {
jcoomes@1993:       while (tq->size() > _target_stack_size && tq->pop_local(p)) {
duke@435:         process_popped_location_depth(p);
duke@435:       }
duke@435:     }
jcoomes@1993:   } while (totally_drain && !tq->taskqueue_empty() || !tq->overflow_empty());
duke@435: 
jcoomes@1993:   assert(!totally_drain || tq->taskqueue_empty(), "Sanity");
jcoomes@1993:   assert(totally_drain || tq->size() <= _target_stack_size, "Sanity");
jcoomes@1993:   assert(tq->overflow_empty(), "Sanity");
duke@435: }
duke@435: 
duke@435: void PSPromotionManager::flush_labs() {
jcoomes@1993:   assert(stacks_empty(), "Attempt to flush lab with live stack");
duke@435: 
duke@435:   // If either promotion lab fills up, we can flush the
duke@435:   // lab but not refill it, so check first.
duke@435:   assert(!_young_lab.is_flushed() || _young_gen_is_full, "Sanity");
duke@435:   if (!_young_lab.is_flushed())
duke@435:     _young_lab.flush();
duke@435: 
duke@435:   assert(!_old_lab.is_flushed() || _old_gen_is_full, "Sanity");
duke@435:   if (!_old_lab.is_flushed())
duke@435:     _old_lab.flush();
duke@435: 
duke@435:   // Let PSScavenge know if we overflowed
duke@435:   if (_young_gen_is_full) {
duke@435:     PSScavenge::set_survivor_overflow(true);
duke@435:   }
duke@435: }
duke@435: 
coleenp@548: template <class T> void PSPromotionManager::process_array_chunk_work(
coleenp@548:                                                  oop obj,
coleenp@548:                                                  int start, int end) {
jwilhelm@2648:   assert(start <= end, "invariant");
coleenp@548:   T* const base      = (T*)objArrayOop(obj)->base();
coleenp@548:   T* p               = base + start;
coleenp@548:   T* const chunk_end = base + end;
coleenp@548:   while (p < chunk_end) {
coleenp@548:     if (PSScavenge::should_scavenge(p)) {
coleenp@548:       claim_or_forward_depth(p);
coleenp@548:     }
coleenp@548:     ++p;
coleenp@548:   }
coleenp@548: }
coleenp@548: 
duke@435: void PSPromotionManager::process_array_chunk(oop old) {
duke@435:   assert(PSChunkLargeArrays, "invariant");
duke@435:   assert(old->is_objArray(), "invariant");
duke@435:   assert(old->is_forwarded(), "invariant");
duke@435: 
jcoomes@2020:   TASKQUEUE_STATS_ONLY(++_array_chunks_processed);
duke@435: 
duke@435:   oop const obj = old->forwardee();
duke@435: 
duke@435:   int start;
duke@435:   int const end = arrayOop(old)->length();
duke@435:   if (end > (int) _min_array_size_for_chunking) {
duke@435:     // we'll chunk more
duke@435:     start = end - _array_chunk_size;
duke@435:     assert(start > 0, "invariant");
duke@435:     arrayOop(old)->set_length(start);
duke@435:     push_depth(mask_chunked_array_oop(old));
jcoomes@2020:     TASKQUEUE_STATS_ONLY(++_masked_pushes);
duke@435:   } else {
duke@435:     // this is the final chunk for this array
duke@435:     start = 0;
duke@435:     int const actual_length = arrayOop(obj)->length();
duke@435:     arrayOop(old)->set_length(actual_length);
duke@435:   }
duke@435: 
coleenp@548:   if (UseCompressedOops) {
coleenp@548:     process_array_chunk_work<narrowOop>(obj, start, end);
coleenp@548:   } else {
coleenp@548:     process_array_chunk_work<oop>(obj, start, end);
duke@435:   }
duke@435: }
duke@435: 
duke@435: oop PSPromotionManager::oop_promotion_failed(oop obj, markOop obj_mark) {
duke@435:   assert(_old_gen_is_full || PromotionFailureALot, "Sanity");
duke@435: 
duke@435:   // Attempt to CAS in the header.
duke@435:   // This tests if the header is still the same as when
duke@435:   // this started.  If it is the same (i.e., no forwarding
duke@435:   // pointer has been installed), then this thread owns
duke@435:   // it.
duke@435:   if (obj->cas_forward_to(obj, obj_mark)) {
duke@435:     // We won any races, we "own" this object.
duke@435:     assert(obj == obj->forwardee(), "Sanity");
duke@435: 
sla@5237:     _promotion_failed_info.register_copy_failure(obj->size());
sla@5237: 
tonyp@2061:     obj->push_contents(this);
duke@435: 
duke@435:     // Save the mark if needed
duke@435:     PSScavenge::oop_promotion_failed(obj, obj_mark);
duke@435:   }  else {
duke@435:     // We lost, someone else "owns" this object
duke@435:     guarantee(obj->is_forwarded(), "Object must be forwarded if the cas failed.");
duke@435: 
duke@435:     // No unallocation to worry about.
duke@435:     obj = obj->forwardee();
duke@435:   }
duke@435: 
coleenp@4037: #ifndef PRODUCT
duke@435:   if (TraceScavenge) {
duke@435:     gclog_or_tty->print_cr("{%s %s 0x%x (%d)}",
duke@435:                            "promotion-failure",
coleenp@4037:                            obj->klass()->internal_name(),
hseigel@5784:                            (void *)obj, obj->size());
duke@435: 
duke@435:   }
duke@435: #endif
duke@435: 
duke@435:   return obj;
duke@435: }