duke@435: /*
xdono@772:  * Copyright 2001-2008 Sun Microsystems, Inc.  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:  *
duke@435:  * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
duke@435:  * CA 95054 USA or visit www.sun.com if you need additional information or
duke@435:  * have any questions.
duke@435:  *
duke@435:  */
duke@435: 
duke@435: # include "incls/_precompiled.incl"
duke@435: # include "incls/_psOldGen.cpp.incl"
duke@435: 
duke@435: inline const char* PSOldGen::select_name() {
duke@435:   return UseParallelOldGC ? "ParOldGen" : "PSOldGen";
duke@435: }
duke@435: 
duke@435: PSOldGen::PSOldGen(ReservedSpace rs, size_t alignment,
duke@435:                    size_t initial_size, size_t min_size, size_t max_size,
duke@435:                    const char* perf_data_name, int level):
duke@435:   _name(select_name()), _init_gen_size(initial_size), _min_gen_size(min_size),
duke@435:   _max_gen_size(max_size)
duke@435: {
duke@435:   initialize(rs, alignment, perf_data_name, level);
duke@435: }
duke@435: 
duke@435: PSOldGen::PSOldGen(size_t initial_size,
duke@435:                    size_t min_size, size_t max_size,
duke@435:                    const char* perf_data_name, int level):
duke@435:   _name(select_name()), _init_gen_size(initial_size), _min_gen_size(min_size),
duke@435:   _max_gen_size(max_size)
duke@435: {}
duke@435: 
duke@435: void PSOldGen::initialize(ReservedSpace rs, size_t alignment,
duke@435:                           const char* perf_data_name, int level) {
duke@435:   initialize_virtual_space(rs, alignment);
duke@435:   initialize_work(perf_data_name, level);
duke@435:   // The old gen can grow to gen_size_limit().  _reserve reflects only
duke@435:   // the current maximum that can be committed.
duke@435:   assert(_reserved.byte_size() <= gen_size_limit(), "Consistency check");
duke@435: }
duke@435: 
duke@435: void PSOldGen::initialize_virtual_space(ReservedSpace rs, size_t alignment) {
duke@435: 
duke@435:   _virtual_space = new PSVirtualSpace(rs, alignment);
duke@435:   if (!_virtual_space->expand_by(_init_gen_size)) {
duke@435:     vm_exit_during_initialization("Could not reserve enough space for "
duke@435:                                   "object heap");
duke@435:   }
duke@435: }
duke@435: 
duke@435: void PSOldGen::initialize_work(const char* perf_data_name, int level) {
duke@435:   //
duke@435:   // Basic memory initialization
duke@435:   //
duke@435: 
duke@435:   MemRegion limit_reserved((HeapWord*)virtual_space()->low_boundary(),
duke@435:     heap_word_size(_max_gen_size));
duke@435:   assert(limit_reserved.byte_size() == _max_gen_size,
duke@435:     "word vs bytes confusion");
duke@435:   //
duke@435:   // Object start stuff
duke@435:   //
duke@435: 
duke@435:   start_array()->initialize(limit_reserved);
duke@435: 
duke@435:   _reserved = MemRegion((HeapWord*)virtual_space()->low_boundary(),
duke@435:                         (HeapWord*)virtual_space()->high_boundary());
duke@435: 
duke@435:   //
duke@435:   // Card table stuff
duke@435:   //
duke@435: 
duke@435:   MemRegion cmr((HeapWord*)virtual_space()->low(),
duke@435:                 (HeapWord*)virtual_space()->high());
jmasa@698:   if (ZapUnusedHeapArea) {
jmasa@698:     // Mangle newly committed space immediately rather than
jmasa@698:     // waiting for the initialization of the space even though
jmasa@698:     // mangling is related to spaces.  Doing it here eliminates
jmasa@698:     // the need to carry along information that a complete mangling
jmasa@698:     // (bottom to end) needs to be done.
jmasa@698:     SpaceMangler::mangle_region(cmr);
jmasa@698:   }
jmasa@698: 
duke@435:   Universe::heap()->barrier_set()->resize_covered_region(cmr);
duke@435: 
duke@435:   CardTableModRefBS* _ct = (CardTableModRefBS*)Universe::heap()->barrier_set();
duke@435:   assert (_ct->kind() == BarrierSet::CardTableModRef, "Sanity");
duke@435: 
duke@435:   // Verify that the start and end of this generation is the start of a card.
duke@435:   // If this wasn't true, a single card could span more than one generation,
duke@435:   // which would cause problems when we commit/uncommit memory, and when we
duke@435:   // clear and dirty cards.
duke@435:   guarantee(_ct->is_card_aligned(_reserved.start()), "generation must be card aligned");
duke@435:   if (_reserved.end() != Universe::heap()->reserved_region().end()) {
duke@435:     // Don't check at the very end of the heap as we'll assert that we're probing off
duke@435:     // the end if we try.
duke@435:     guarantee(_ct->is_card_aligned(_reserved.end()), "generation must be card aligned");
duke@435:   }
duke@435: 
duke@435:   //
duke@435:   // ObjectSpace stuff
duke@435:   //
duke@435: 
duke@435:   _object_space = new MutableSpace();
duke@435: 
duke@435:   if (_object_space == NULL)
duke@435:     vm_exit_during_initialization("Could not allocate an old gen space");
duke@435: 
jmasa@698:   object_space()->initialize(cmr,
jmasa@698:                              SpaceDecorator::Clear,
jmasa@698:                              SpaceDecorator::Mangle);
duke@435: 
duke@435:   _object_mark_sweep = new PSMarkSweepDecorator(_object_space, start_array(), MarkSweepDeadRatio);
duke@435: 
duke@435:   if (_object_mark_sweep == NULL)
duke@435:     vm_exit_during_initialization("Could not complete allocation of old generation");
duke@435: 
duke@435:   // Update the start_array
duke@435:   start_array()->set_covered_region(cmr);
duke@435: 
duke@435:   // Generation Counters, generation 'level', 1 subspace
duke@435:   _gen_counters = new PSGenerationCounters(perf_data_name, level, 1,
duke@435:                                            virtual_space());
duke@435:   _space_counters = new SpaceCounters(perf_data_name, 0,
duke@435:                                       virtual_space()->reserved_size(),
duke@435:                                       _object_space, _gen_counters);
duke@435: }
duke@435: 
duke@435: // Assume that the generation has been allocated if its
duke@435: // reserved size is not 0.
duke@435: bool  PSOldGen::is_allocated() {
duke@435:   return virtual_space()->reserved_size() != 0;
duke@435: }
duke@435: 
duke@435: void PSOldGen::precompact() {
duke@435:   ParallelScavengeHeap* heap = (ParallelScavengeHeap*)Universe::heap();
duke@435:   assert(heap->kind() == CollectedHeap::ParallelScavengeHeap, "Sanity");
duke@435: 
duke@435:   // Reset start array first.
duke@435:   start_array()->reset();
duke@435: 
duke@435:   object_mark_sweep()->precompact();
duke@435: 
duke@435:   // Now compact the young gen
duke@435:   heap->young_gen()->precompact();
duke@435: }
duke@435: 
duke@435: void PSOldGen::adjust_pointers() {
duke@435:   object_mark_sweep()->adjust_pointers();
duke@435: }
duke@435: 
duke@435: void PSOldGen::compact() {
duke@435:   object_mark_sweep()->compact(ZapUnusedHeapArea);
duke@435: }
duke@435: 
duke@435: void PSOldGen::move_and_update(ParCompactionManager* cm) {
duke@435:   PSParallelCompact::move_and_update(cm, PSParallelCompact::old_space_id);
duke@435: }
duke@435: 
duke@435: size_t PSOldGen::contiguous_available() const {
duke@435:   return object_space()->free_in_bytes() + virtual_space()->uncommitted_size();
duke@435: }
duke@435: 
duke@435: // Allocation. We report all successful allocations to the size policy
duke@435: // Note that the perm gen does not use this method, and should not!
duke@435: HeapWord* PSOldGen::allocate(size_t word_size, bool is_tlab) {
duke@435:   assert_locked_or_safepoint(Heap_lock);
duke@435:   HeapWord* res = allocate_noexpand(word_size, is_tlab);
duke@435: 
duke@435:   if (res == NULL) {
duke@435:     res = expand_and_allocate(word_size, is_tlab);
duke@435:   }
duke@435: 
duke@435:   // Allocations in the old generation need to be reported
duke@435:   if (res != NULL) {
duke@435:     ParallelScavengeHeap* heap = (ParallelScavengeHeap*)Universe::heap();
duke@435:     heap->size_policy()->tenured_allocation(word_size);
duke@435:   }
duke@435: 
duke@435:   return res;
duke@435: }
duke@435: 
duke@435: HeapWord* PSOldGen::expand_and_allocate(size_t word_size, bool is_tlab) {
duke@435:   assert(!is_tlab, "TLAB's are not supported in PSOldGen");
duke@435:   expand(word_size*HeapWordSize);
duke@435:   if (GCExpandToAllocateDelayMillis > 0) {
duke@435:     os::sleep(Thread::current(), GCExpandToAllocateDelayMillis, false);
duke@435:   }
duke@435:   return allocate_noexpand(word_size, is_tlab);
duke@435: }
duke@435: 
duke@435: HeapWord* PSOldGen::expand_and_cas_allocate(size_t word_size) {
duke@435:   expand(word_size*HeapWordSize);
duke@435:   if (GCExpandToAllocateDelayMillis > 0) {
duke@435:     os::sleep(Thread::current(), GCExpandToAllocateDelayMillis, false);
duke@435:   }
duke@435:   return cas_allocate_noexpand(word_size);
duke@435: }
duke@435: 
duke@435: void PSOldGen::expand(size_t bytes) {
jmasa@706:   if (bytes == 0) {
jmasa@706:     return;
jmasa@706:   }
duke@435:   MutexLocker x(ExpandHeap_lock);
duke@435:   const size_t alignment = virtual_space()->alignment();
duke@435:   size_t aligned_bytes  = align_size_up(bytes, alignment);
duke@435:   size_t aligned_expand_bytes = align_size_up(MinHeapDeltaBytes, alignment);
jmasa@706:   if (aligned_bytes == 0){
jmasa@706:     // The alignment caused the number of bytes to wrap.  An expand_by(0) will
jmasa@706:     // return true with the implication that and expansion was done when it
jmasa@706:     // was not.  A call to expand implies a best effort to expand by "bytes"
jmasa@706:     // but not a guarantee.  Align down to give a best effort.  This is likely
jmasa@706:     // the most that the generation can expand since it has some capacity to
jmasa@706:     // start with.
jmasa@706:     aligned_bytes = align_size_down(bytes, alignment);
jmasa@706:   }
duke@435: 
duke@435:   bool success = false;
duke@435:   if (aligned_expand_bytes > aligned_bytes) {
duke@435:     success = expand_by(aligned_expand_bytes);
duke@435:   }
duke@435:   if (!success) {
duke@435:     success = expand_by(aligned_bytes);
duke@435:   }
duke@435:   if (!success) {
duke@435:     success = expand_to_reserved();
duke@435:   }
duke@435: 
jmasa@706:   if (PrintGC && Verbose) {
jmasa@706:     if (success && GC_locker::is_active()) {
duke@435:       gclog_or_tty->print_cr("Garbage collection disabled, expanded heap instead");
duke@435:     }
duke@435:   }
duke@435: }
duke@435: 
duke@435: bool PSOldGen::expand_by(size_t bytes) {
duke@435:   assert_lock_strong(ExpandHeap_lock);
duke@435:   assert_locked_or_safepoint(Heap_lock);
jmasa@706:   if (bytes == 0) {
jmasa@706:     return true;  // That's what virtual_space()->expand_by(0) would return
jmasa@706:   }
duke@435:   bool result = virtual_space()->expand_by(bytes);
duke@435:   if (result) {
jmasa@698:     if (ZapUnusedHeapArea) {
jmasa@698:       // We need to mangle the newly expanded area. The memregion spans
jmasa@698:       // end -> new_end, we assume that top -> end is already mangled.
jmasa@698:       // Do the mangling before post_resize() is called because
jmasa@698:       // the space is available for allocation after post_resize();
jmasa@698:       HeapWord* const virtual_space_high = (HeapWord*) virtual_space()->high();
jmasa@698:       assert(object_space()->end() < virtual_space_high,
jmasa@698:         "Should be true before post_resize()");
jmasa@698:       MemRegion mangle_region(object_space()->end(), virtual_space_high);
jmasa@698:       // Note that the object space has not yet been updated to
jmasa@698:       // coincede with the new underlying virtual space.
jmasa@698:       SpaceMangler::mangle_region(mangle_region);
jmasa@698:     }
duke@435:     post_resize();
duke@435:     if (UsePerfData) {
duke@435:       _space_counters->update_capacity();
duke@435:       _gen_counters->update_all();
duke@435:     }
duke@435:   }
duke@435: 
duke@435:   if (result && Verbose && PrintGC) {
duke@435:     size_t new_mem_size = virtual_space()->committed_size();
duke@435:     size_t old_mem_size = new_mem_size - bytes;
duke@435:     gclog_or_tty->print_cr("Expanding %s from " SIZE_FORMAT "K by "
duke@435:                                        SIZE_FORMAT "K to "
duke@435:                                        SIZE_FORMAT "K",
duke@435:                     name(), old_mem_size/K, bytes/K, new_mem_size/K);
duke@435:   }
duke@435: 
duke@435:   return result;
duke@435: }
duke@435: 
duke@435: bool PSOldGen::expand_to_reserved() {
duke@435:   assert_lock_strong(ExpandHeap_lock);
duke@435:   assert_locked_or_safepoint(Heap_lock);
duke@435: 
duke@435:   bool result = true;
duke@435:   const size_t remaining_bytes = virtual_space()->uncommitted_size();
duke@435:   if (remaining_bytes > 0) {
duke@435:     result = expand_by(remaining_bytes);
duke@435:     DEBUG_ONLY(if (!result) warning("grow to reserve failed"));
duke@435:   }
duke@435:   return result;
duke@435: }
duke@435: 
duke@435: void PSOldGen::shrink(size_t bytes) {
duke@435:   assert_lock_strong(ExpandHeap_lock);
duke@435:   assert_locked_or_safepoint(Heap_lock);
duke@435: 
duke@435:   size_t size = align_size_down(bytes, virtual_space()->alignment());
duke@435:   if (size > 0) {
duke@435:     assert_lock_strong(ExpandHeap_lock);
duke@435:     virtual_space()->shrink_by(bytes);
duke@435:     post_resize();
duke@435: 
duke@435:     if (Verbose && PrintGC) {
duke@435:       size_t new_mem_size = virtual_space()->committed_size();
duke@435:       size_t old_mem_size = new_mem_size + bytes;
duke@435:       gclog_or_tty->print_cr("Shrinking %s from " SIZE_FORMAT "K by "
duke@435:                                          SIZE_FORMAT "K to "
duke@435:                                          SIZE_FORMAT "K",
duke@435:                       name(), old_mem_size/K, bytes/K, new_mem_size/K);
duke@435:     }
duke@435:   }
duke@435: }
duke@435: 
duke@435: void PSOldGen::resize(size_t desired_free_space) {
duke@435:   const size_t alignment = virtual_space()->alignment();
duke@435:   const size_t size_before = virtual_space()->committed_size();
duke@435:   size_t new_size = used_in_bytes() + desired_free_space;
duke@435:   if (new_size < used_in_bytes()) {
duke@435:     // Overflowed the addition.
duke@435:     new_size = gen_size_limit();
duke@435:   }
duke@435:   // Adjust according to our min and max
duke@435:   new_size = MAX2(MIN2(new_size, gen_size_limit()), min_gen_size());
duke@435: 
duke@435:   assert(gen_size_limit() >= reserved().byte_size(), "max new size problem?");
duke@435:   new_size = align_size_up(new_size, alignment);
duke@435: 
duke@435:   const size_t current_size = capacity_in_bytes();
duke@435: 
duke@435:   if (PrintAdaptiveSizePolicy && Verbose) {
duke@435:     gclog_or_tty->print_cr("AdaptiveSizePolicy::old generation size: "
duke@435:       "desired free: " SIZE_FORMAT " used: " SIZE_FORMAT
duke@435:       " new size: " SIZE_FORMAT " current size " SIZE_FORMAT
duke@435:       " gen limits: " SIZE_FORMAT " / " SIZE_FORMAT,
duke@435:       desired_free_space, used_in_bytes(), new_size, current_size,
duke@435:       gen_size_limit(), min_gen_size());
duke@435:   }
duke@435: 
duke@435:   if (new_size == current_size) {
duke@435:     // No change requested
duke@435:     return;
duke@435:   }
duke@435:   if (new_size > current_size) {
duke@435:     size_t change_bytes = new_size - current_size;
duke@435:     expand(change_bytes);
duke@435:   } else {
duke@435:     size_t change_bytes = current_size - new_size;
duke@435:     // shrink doesn't grab this lock, expand does. Is that right?
duke@435:     MutexLocker x(ExpandHeap_lock);
duke@435:     shrink(change_bytes);
duke@435:   }
duke@435: 
duke@435:   if (PrintAdaptiveSizePolicy) {
duke@435:     ParallelScavengeHeap* heap = (ParallelScavengeHeap*)Universe::heap();
duke@435:     assert(heap->kind() == CollectedHeap::ParallelScavengeHeap, "Sanity");
duke@435:     gclog_or_tty->print_cr("AdaptiveSizePolicy::old generation size: "
duke@435:                   "collection: %d "
duke@435:                   "(" SIZE_FORMAT ") -> (" SIZE_FORMAT ") ",
duke@435:                   heap->total_collections(),
duke@435:                   size_before, virtual_space()->committed_size());
duke@435:   }
duke@435: }
duke@435: 
duke@435: // NOTE! We need to be careful about resizing. During a GC, multiple
duke@435: // allocators may be active during heap expansion. If we allow the
duke@435: // heap resizing to become visible before we have correctly resized
duke@435: // all heap related data structures, we may cause program failures.
duke@435: void PSOldGen::post_resize() {
duke@435:   // First construct a memregion representing the new size
duke@435:   MemRegion new_memregion((HeapWord*)virtual_space()->low(),
duke@435:     (HeapWord*)virtual_space()->high());
duke@435:   size_t new_word_size = new_memregion.word_size();
duke@435: 
duke@435:   start_array()->set_covered_region(new_memregion);
duke@435:   Universe::heap()->barrier_set()->resize_covered_region(new_memregion);
duke@435: 
duke@435:   HeapWord* const virtual_space_high = (HeapWord*) virtual_space()->high();
duke@435: 
duke@435:   // ALWAYS do this last!!
duke@435:   object_space()->set_end(virtual_space_high);
duke@435: 
duke@435:   assert(new_word_size == heap_word_size(object_space()->capacity_in_bytes()),
duke@435:     "Sanity");
duke@435: }
duke@435: 
duke@435: size_t PSOldGen::gen_size_limit() {
duke@435:   return _max_gen_size;
duke@435: }
duke@435: 
duke@435: void PSOldGen::reset_after_change() {
duke@435:   ShouldNotReachHere();
duke@435:   return;
duke@435: }
duke@435: 
duke@435: size_t PSOldGen::available_for_expansion() {
duke@435:   ShouldNotReachHere();
duke@435:   return 0;
duke@435: }
duke@435: 
duke@435: size_t PSOldGen::available_for_contraction() {
duke@435:   ShouldNotReachHere();
duke@435:   return 0;
duke@435: }
duke@435: 
duke@435: void PSOldGen::print() const { print_on(tty);}
duke@435: void PSOldGen::print_on(outputStream* st) const {
duke@435:   st->print(" %-15s", name());
duke@435:   if (PrintGCDetails && Verbose) {
duke@435:     st->print(" total " SIZE_FORMAT ", used " SIZE_FORMAT,
duke@435:                 capacity_in_bytes(), used_in_bytes());
duke@435:   } else {
duke@435:     st->print(" total " SIZE_FORMAT "K, used " SIZE_FORMAT "K",
duke@435:                 capacity_in_bytes()/K, used_in_bytes()/K);
duke@435:   }
duke@435:   st->print_cr(" [" INTPTR_FORMAT ", " INTPTR_FORMAT ", " INTPTR_FORMAT ")",
duke@435:                 virtual_space()->low_boundary(),
duke@435:                 virtual_space()->high(),
duke@435:                 virtual_space()->high_boundary());
duke@435: 
duke@435:   st->print("  object"); object_space()->print_on(st);
duke@435: }
duke@435: 
duke@435: void PSOldGen::print_used_change(size_t prev_used) const {
duke@435:   gclog_or_tty->print(" [%s:", name());
duke@435:   gclog_or_tty->print(" "  SIZE_FORMAT "K"
duke@435:                       "->" SIZE_FORMAT "K"
duke@435:                       "("  SIZE_FORMAT "K)",
duke@435:                       prev_used / K, used_in_bytes() / K,
duke@435:                       capacity_in_bytes() / K);
duke@435:   gclog_or_tty->print("]");
duke@435: }
duke@435: 
duke@435: void PSOldGen::update_counters() {
duke@435:   if (UsePerfData) {
duke@435:     _space_counters->update_all();
duke@435:     _gen_counters->update_all();
duke@435:   }
duke@435: }
duke@435: 
duke@435: #ifndef PRODUCT
duke@435: 
duke@435: void PSOldGen::space_invariants() {
duke@435:   assert(object_space()->end() == (HeapWord*) virtual_space()->high(),
duke@435:     "Space invariant");
duke@435:   assert(object_space()->bottom() == (HeapWord*) virtual_space()->low(),
duke@435:     "Space invariant");
duke@435:   assert(virtual_space()->low_boundary() <= virtual_space()->low(),
duke@435:     "Space invariant");
duke@435:   assert(virtual_space()->high_boundary() >= virtual_space()->high(),
duke@435:     "Space invariant");
duke@435:   assert(virtual_space()->low_boundary() == (char*) _reserved.start(),
duke@435:     "Space invariant");
duke@435:   assert(virtual_space()->high_boundary() == (char*) _reserved.end(),
duke@435:     "Space invariant");
duke@435:   assert(virtual_space()->committed_size() <= virtual_space()->reserved_size(),
duke@435:     "Space invariant");
duke@435: }
duke@435: #endif
duke@435: 
duke@435: void PSOldGen::verify(bool allow_dirty) {
duke@435:   object_space()->verify(allow_dirty);
duke@435: }
duke@435: class VerifyObjectStartArrayClosure : public ObjectClosure {
duke@435:   PSOldGen* _gen;
duke@435:   ObjectStartArray* _start_array;
duke@435: 
duke@435:  public:
duke@435:   VerifyObjectStartArrayClosure(PSOldGen* gen, ObjectStartArray* start_array) :
duke@435:     _gen(gen), _start_array(start_array) { }
duke@435: 
duke@435:   virtual void do_object(oop obj) {
duke@435:     HeapWord* test_addr = (HeapWord*)obj + 1;
duke@435:     guarantee(_start_array->object_start(test_addr) == (HeapWord*)obj, "ObjectStartArray cannot find start of object");
duke@435:     guarantee(_start_array->is_block_allocated((HeapWord*)obj), "ObjectStartArray missing block allocation");
duke@435:   }
duke@435: };
duke@435: 
duke@435: void PSOldGen::verify_object_start_array() {
duke@435:   VerifyObjectStartArrayClosure check( this, &_start_array );
duke@435:   object_iterate(&check);
duke@435: }
jmasa@698: 
jmasa@698: #ifndef PRODUCT
jmasa@698: void PSOldGen::record_spaces_top() {
jmasa@698:   assert(ZapUnusedHeapArea, "Not mangling unused space");
jmasa@698:   object_space()->set_top_for_allocations();
jmasa@698: }
jmasa@698: #endif