--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/src/share/vm/gc_implementation/parallelScavenge/psOldGen.cpp	Sat Dec 01 00:00:00 2007 +0000
@@ -0,0 +1,464 @@
+/*
+ * Copyright 2001-2007 Sun Microsystems, Inc.  All Rights Reserved.
+ * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
+ *
+ * This code is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 only, as
+ * published by the Free Software Foundation.
+ *
+ * This code is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
+ * version 2 for more details (a copy is included in the LICENSE file that
+ * accompanied this code).
+ *
+ * You should have received a copy of the GNU General Public License version
+ * 2 along with this work; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
+ * CA 95054 USA or visit www.sun.com if you need additional information or
+ * have any questions.
+ *
+ */
+
+# include "incls/_precompiled.incl"
+# include "incls/_psOldGen.cpp.incl"
+
+inline const char* PSOldGen::select_name() {
+  return UseParallelOldGC ? "ParOldGen" : "PSOldGen";
+}
+
+PSOldGen::PSOldGen(ReservedSpace rs, size_t alignment,
+                   size_t initial_size, size_t min_size, size_t max_size,
+                   const char* perf_data_name, int level):
+  _name(select_name()), _init_gen_size(initial_size), _min_gen_size(min_size),
+  _max_gen_size(max_size)
+{
+  initialize(rs, alignment, perf_data_name, level);
+}
+
+PSOldGen::PSOldGen(size_t initial_size,
+                   size_t min_size, size_t max_size,
+                   const char* perf_data_name, int level):
+  _name(select_name()), _init_gen_size(initial_size), _min_gen_size(min_size),
+  _max_gen_size(max_size)
+{}
+
+void PSOldGen::initialize(ReservedSpace rs, size_t alignment,
+                          const char* perf_data_name, int level) {
+  initialize_virtual_space(rs, alignment);
+  initialize_work(perf_data_name, level);
+  // The old gen can grow to gen_size_limit().  _reserve reflects only
+  // the current maximum that can be committed.
+  assert(_reserved.byte_size() <= gen_size_limit(), "Consistency check");
+}
+
+void PSOldGen::initialize_virtual_space(ReservedSpace rs, size_t alignment) {
+
+  _virtual_space = new PSVirtualSpace(rs, alignment);
+  if (!_virtual_space->expand_by(_init_gen_size)) {
+    vm_exit_during_initialization("Could not reserve enough space for "
+                                  "object heap");
+  }
+}
+
+void PSOldGen::initialize_work(const char* perf_data_name, int level) {
+  //
+  // Basic memory initialization
+  //
+
+  MemRegion limit_reserved((HeapWord*)virtual_space()->low_boundary(),
+    heap_word_size(_max_gen_size));
+  assert(limit_reserved.byte_size() == _max_gen_size,
+    "word vs bytes confusion");
+  //
+  // Object start stuff
+  //
+
+  start_array()->initialize(limit_reserved);
+
+  _reserved = MemRegion((HeapWord*)virtual_space()->low_boundary(),
+                        (HeapWord*)virtual_space()->high_boundary());
+
+  //
+  // Card table stuff
+  //
+
+  MemRegion cmr((HeapWord*)virtual_space()->low(),
+                (HeapWord*)virtual_space()->high());
+  Universe::heap()->barrier_set()->resize_covered_region(cmr);
+
+  CardTableModRefBS* _ct = (CardTableModRefBS*)Universe::heap()->barrier_set();
+  assert (_ct->kind() == BarrierSet::CardTableModRef, "Sanity");
+
+  // Verify that the start and end of this generation is the start of a card.
+  // If this wasn't true, a single card could span more than one generation,
+  // which would cause problems when we commit/uncommit memory, and when we
+  // clear and dirty cards.
+  guarantee(_ct->is_card_aligned(_reserved.start()), "generation must be card aligned");
+  if (_reserved.end() != Universe::heap()->reserved_region().end()) {
+    // Don't check at the very end of the heap as we'll assert that we're probing off
+    // the end if we try.
+    guarantee(_ct->is_card_aligned(_reserved.end()), "generation must be card aligned");
+  }
+
+  //
+  // ObjectSpace stuff
+  //
+
+  _object_space = new MutableSpace();
+
+  if (_object_space == NULL)
+    vm_exit_during_initialization("Could not allocate an old gen space");
+
+  object_space()->initialize(cmr, true);
+
+  _object_mark_sweep = new PSMarkSweepDecorator(_object_space, start_array(), MarkSweepDeadRatio);
+
+  if (_object_mark_sweep == NULL)
+    vm_exit_during_initialization("Could not complete allocation of old generation");
+
+  // Update the start_array
+  start_array()->set_covered_region(cmr);
+
+  // Generation Counters, generation 'level', 1 subspace
+  _gen_counters = new PSGenerationCounters(perf_data_name, level, 1,
+                                           virtual_space());
+  _space_counters = new SpaceCounters(perf_data_name, 0,
+                                      virtual_space()->reserved_size(),
+                                      _object_space, _gen_counters);
+}
+
+// Assume that the generation has been allocated if its
+// reserved size is not 0.
+bool  PSOldGen::is_allocated() {
+  return virtual_space()->reserved_size() != 0;
+}
+
+void PSOldGen::precompact() {
+  ParallelScavengeHeap* heap = (ParallelScavengeHeap*)Universe::heap();
+  assert(heap->kind() == CollectedHeap::ParallelScavengeHeap, "Sanity");
+
+  // Reset start array first.
+  debug_only(if (!UseParallelOldGC || !VerifyParallelOldWithMarkSweep) {)
+  start_array()->reset();
+  debug_only(})
+
+  object_mark_sweep()->precompact();
+
+  // Now compact the young gen
+  heap->young_gen()->precompact();
+}
+
+void PSOldGen::adjust_pointers() {
+  object_mark_sweep()->adjust_pointers();
+}
+
+void PSOldGen::compact() {
+  object_mark_sweep()->compact(ZapUnusedHeapArea);
+}
+
+void PSOldGen::move_and_update(ParCompactionManager* cm) {
+  PSParallelCompact::move_and_update(cm, PSParallelCompact::old_space_id);
+}
+
+size_t PSOldGen::contiguous_available() const {
+  return object_space()->free_in_bytes() + virtual_space()->uncommitted_size();
+}
+
+// Allocation. We report all successful allocations to the size policy
+// Note that the perm gen does not use this method, and should not!
+HeapWord* PSOldGen::allocate(size_t word_size, bool is_tlab) {
+  assert_locked_or_safepoint(Heap_lock);
+  HeapWord* res = allocate_noexpand(word_size, is_tlab);
+
+  if (res == NULL) {
+    res = expand_and_allocate(word_size, is_tlab);
+  }
+
+  // Allocations in the old generation need to be reported
+  if (res != NULL) {
+    ParallelScavengeHeap* heap = (ParallelScavengeHeap*)Universe::heap();
+    heap->size_policy()->tenured_allocation(word_size);
+  }
+
+  return res;
+}
+
+HeapWord* PSOldGen::expand_and_allocate(size_t word_size, bool is_tlab) {
+  assert(!is_tlab, "TLAB's are not supported in PSOldGen");
+  expand(word_size*HeapWordSize);
+  if (GCExpandToAllocateDelayMillis > 0) {
+    os::sleep(Thread::current(), GCExpandToAllocateDelayMillis, false);
+  }
+  return allocate_noexpand(word_size, is_tlab);
+}
+
+HeapWord* PSOldGen::expand_and_cas_allocate(size_t word_size) {
+  expand(word_size*HeapWordSize);
+  if (GCExpandToAllocateDelayMillis > 0) {
+    os::sleep(Thread::current(), GCExpandToAllocateDelayMillis, false);
+  }
+  return cas_allocate_noexpand(word_size);
+}
+
+void PSOldGen::expand(size_t bytes) {
+  MutexLocker x(ExpandHeap_lock);
+  const size_t alignment = virtual_space()->alignment();
+  size_t aligned_bytes  = align_size_up(bytes, alignment);
+  size_t aligned_expand_bytes = align_size_up(MinHeapDeltaBytes, alignment);
+
+  bool success = false;
+  if (aligned_expand_bytes > aligned_bytes) {
+    success = expand_by(aligned_expand_bytes);
+  }
+  if (!success) {
+    success = expand_by(aligned_bytes);
+  }
+  if (!success) {
+    success = expand_to_reserved();
+  }
+
+  if (GC_locker::is_active()) {
+    if (PrintGC && Verbose) {
+      gclog_or_tty->print_cr("Garbage collection disabled, expanded heap instead");
+    }
+  }
+}
+
+bool PSOldGen::expand_by(size_t bytes) {
+  assert_lock_strong(ExpandHeap_lock);
+  assert_locked_or_safepoint(Heap_lock);
+  bool result = virtual_space()->expand_by(bytes);
+  if (result) {
+    post_resize();
+    if (UsePerfData) {
+      _space_counters->update_capacity();
+      _gen_counters->update_all();
+    }
+  }
+
+  if (result && Verbose && PrintGC) {
+    size_t new_mem_size = virtual_space()->committed_size();
+    size_t old_mem_size = new_mem_size - bytes;
+    gclog_or_tty->print_cr("Expanding %s from " SIZE_FORMAT "K by "
+                                       SIZE_FORMAT "K to "
+                                       SIZE_FORMAT "K",
+                    name(), old_mem_size/K, bytes/K, new_mem_size/K);
+  }
+
+  return result;
+}
+
+bool PSOldGen::expand_to_reserved() {
+  assert_lock_strong(ExpandHeap_lock);
+  assert_locked_or_safepoint(Heap_lock);
+
+  bool result = true;
+  const size_t remaining_bytes = virtual_space()->uncommitted_size();
+  if (remaining_bytes > 0) {
+    result = expand_by(remaining_bytes);
+    DEBUG_ONLY(if (!result) warning("grow to reserve failed"));
+  }
+  return result;
+}
+
+void PSOldGen::shrink(size_t bytes) {
+  assert_lock_strong(ExpandHeap_lock);
+  assert_locked_or_safepoint(Heap_lock);
+
+  size_t size = align_size_down(bytes, virtual_space()->alignment());
+  if (size > 0) {
+    assert_lock_strong(ExpandHeap_lock);
+    virtual_space()->shrink_by(bytes);
+    post_resize();
+
+    if (Verbose && PrintGC) {
+      size_t new_mem_size = virtual_space()->committed_size();
+      size_t old_mem_size = new_mem_size + bytes;
+      gclog_or_tty->print_cr("Shrinking %s from " SIZE_FORMAT "K by "
+                                         SIZE_FORMAT "K to "
+                                         SIZE_FORMAT "K",
+                      name(), old_mem_size/K, bytes/K, new_mem_size/K);
+    }
+  }
+}
+
+void PSOldGen::resize(size_t desired_free_space) {
+  const size_t alignment = virtual_space()->alignment();
+  const size_t size_before = virtual_space()->committed_size();
+  size_t new_size = used_in_bytes() + desired_free_space;
+  if (new_size < used_in_bytes()) {
+    // Overflowed the addition.
+    new_size = gen_size_limit();
+  }
+  // Adjust according to our min and max
+  new_size = MAX2(MIN2(new_size, gen_size_limit()), min_gen_size());
+
+  assert(gen_size_limit() >= reserved().byte_size(), "max new size problem?");
+  new_size = align_size_up(new_size, alignment);
+
+  const size_t current_size = capacity_in_bytes();
+
+  if (PrintAdaptiveSizePolicy && Verbose) {
+    gclog_or_tty->print_cr("AdaptiveSizePolicy::old generation size: "
+      "desired free: " SIZE_FORMAT " used: " SIZE_FORMAT
+      " new size: " SIZE_FORMAT " current size " SIZE_FORMAT
+      " gen limits: " SIZE_FORMAT " / " SIZE_FORMAT,
+      desired_free_space, used_in_bytes(), new_size, current_size,
+      gen_size_limit(), min_gen_size());
+  }
+
+  if (new_size == current_size) {
+    // No change requested
+    return;
+  }
+  if (new_size > current_size) {
+    size_t change_bytes = new_size - current_size;
+    expand(change_bytes);
+  } else {
+    size_t change_bytes = current_size - new_size;
+    // shrink doesn't grab this lock, expand does. Is that right?
+    MutexLocker x(ExpandHeap_lock);
+    shrink(change_bytes);
+  }
+
+  if (PrintAdaptiveSizePolicy) {
+    ParallelScavengeHeap* heap = (ParallelScavengeHeap*)Universe::heap();
+    assert(heap->kind() == CollectedHeap::ParallelScavengeHeap, "Sanity");
+    gclog_or_tty->print_cr("AdaptiveSizePolicy::old generation size: "
+                  "collection: %d "
+                  "(" SIZE_FORMAT ") -> (" SIZE_FORMAT ") ",
+                  heap->total_collections(),
+                  size_before, virtual_space()->committed_size());
+  }
+}
+
+// NOTE! We need to be careful about resizing. During a GC, multiple
+// allocators may be active during heap expansion. If we allow the
+// heap resizing to become visible before we have correctly resized
+// all heap related data structures, we may cause program failures.
+void PSOldGen::post_resize() {
+  // First construct a memregion representing the new size
+  MemRegion new_memregion((HeapWord*)virtual_space()->low(),
+    (HeapWord*)virtual_space()->high());
+  size_t new_word_size = new_memregion.word_size();
+
+  start_array()->set_covered_region(new_memregion);
+  Universe::heap()->barrier_set()->resize_covered_region(new_memregion);
+
+  // Did we expand?
+  HeapWord* const virtual_space_high = (HeapWord*) virtual_space()->high();
+  if (object_space()->end() < virtual_space_high) {
+    // We need to mangle the newly expanded area. The memregion spans
+    // end -> new_end, we assume that top -> end is already mangled.
+    // This cannot be safely tested for, as allocation may be taking
+    // place.
+    MemRegion mangle_region(object_space()->end(), virtual_space_high);
+    object_space()->mangle_region(mangle_region);
+  }
+
+  // ALWAYS do this last!!
+  object_space()->set_end(virtual_space_high);
+
+  assert(new_word_size == heap_word_size(object_space()->capacity_in_bytes()),
+    "Sanity");
+}
+
+size_t PSOldGen::gen_size_limit() {
+  return _max_gen_size;
+}
+
+void PSOldGen::reset_after_change() {
+  ShouldNotReachHere();
+  return;
+}
+
+size_t PSOldGen::available_for_expansion() {
+  ShouldNotReachHere();
+  return 0;
+}
+
+size_t PSOldGen::available_for_contraction() {
+  ShouldNotReachHere();
+  return 0;
+}
+
+void PSOldGen::print() const { print_on(tty);}
+void PSOldGen::print_on(outputStream* st) const {
+  st->print(" %-15s", name());
+  if (PrintGCDetails && Verbose) {
+    st->print(" total " SIZE_FORMAT ", used " SIZE_FORMAT,
+                capacity_in_bytes(), used_in_bytes());
+  } else {
+    st->print(" total " SIZE_FORMAT "K, used " SIZE_FORMAT "K",
+                capacity_in_bytes()/K, used_in_bytes()/K);
+  }
+  st->print_cr(" [" INTPTR_FORMAT ", " INTPTR_FORMAT ", " INTPTR_FORMAT ")",
+                virtual_space()->low_boundary(),
+                virtual_space()->high(),
+                virtual_space()->high_boundary());
+
+  st->print("  object"); object_space()->print_on(st);
+}
+
+void PSOldGen::print_used_change(size_t prev_used) const {
+  gclog_or_tty->print(" [%s:", name());
+  gclog_or_tty->print(" "  SIZE_FORMAT "K"
+                      "->" SIZE_FORMAT "K"
+                      "("  SIZE_FORMAT "K)",
+                      prev_used / K, used_in_bytes() / K,
+                      capacity_in_bytes() / K);
+  gclog_or_tty->print("]");
+}
+
+void PSOldGen::update_counters() {
+  if (UsePerfData) {
+    _space_counters->update_all();
+    _gen_counters->update_all();
+  }
+}
+
+#ifndef PRODUCT
+
+void PSOldGen::space_invariants() {
+  assert(object_space()->end() == (HeapWord*) virtual_space()->high(),
+    "Space invariant");
+  assert(object_space()->bottom() == (HeapWord*) virtual_space()->low(),
+    "Space invariant");
+  assert(virtual_space()->low_boundary() <= virtual_space()->low(),
+    "Space invariant");
+  assert(virtual_space()->high_boundary() >= virtual_space()->high(),
+    "Space invariant");
+  assert(virtual_space()->low_boundary() == (char*) _reserved.start(),
+    "Space invariant");
+  assert(virtual_space()->high_boundary() == (char*) _reserved.end(),
+    "Space invariant");
+  assert(virtual_space()->committed_size() <= virtual_space()->reserved_size(),
+    "Space invariant");
+}
+#endif
+
+void PSOldGen::verify(bool allow_dirty) {
+  object_space()->verify(allow_dirty);
+}
+class VerifyObjectStartArrayClosure : public ObjectClosure {
+  PSOldGen* _gen;
+  ObjectStartArray* _start_array;
+
+ public:
+  VerifyObjectStartArrayClosure(PSOldGen* gen, ObjectStartArray* start_array) :
+    _gen(gen), _start_array(start_array) { }
+
+  virtual void do_object(oop obj) {
+    HeapWord* test_addr = (HeapWord*)obj + 1;
+    guarantee(_start_array->object_start(test_addr) == (HeapWord*)obj, "ObjectStartArray cannot find start of object");
+    guarantee(_start_array->is_block_allocated((HeapWord*)obj), "ObjectStartArray missing block allocation");
+  }
+};
+
+void PSOldGen::verify_object_start_array() {
+  VerifyObjectStartArrayClosure check( this, &_start_array );
+  object_iterate(&check);
+}