view src/share/vm/gc_implementation/g1/g1CollectedHeap.inline.hpp @ 2035:0fa27f37d4d4

6977804: G1: remove the zero-filling thread Summary: This changeset removes the zero-filling thread from G1 and collapses the two free region lists we had before (the "free" and "unclean" lists) into one. The new free list uses the new heap region sets / lists abstractions that we'll ultimately use it to keep track of all regions in the heap. A heap region set was also introduced for the humongous regions. Finally, this change increases the concurrency between the thread that completes freeing regions (after a cleanup pause) and the rest of the system (before we'd have to wait for said thread to complete before allocating a new region). The changest also includes a lot of refactoring and code simplification. Reviewed-by: jcoomes, johnc
author tonyp
date Wed, 19 Jan 2011 19:30:42 -0500
parents 7e37af9d69ef
children
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/*
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 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
 *
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 * 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.
 *
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#ifndef SHARE_VM_GC_IMPLEMENTATION_G1_G1COLLECTEDHEAP_INLINE_HPP
#define SHARE_VM_GC_IMPLEMENTATION_G1_G1COLLECTEDHEAP_INLINE_HPP

#include "gc_implementation/g1/concurrentMark.hpp"
#include "gc_implementation/g1/g1CollectedHeap.hpp"
#include "gc_implementation/g1/g1CollectorPolicy.hpp"
#include "gc_implementation/g1/heapRegionSeq.inline.hpp"
#include "utilities/taskqueue.hpp"

// Inline functions for G1CollectedHeap

inline HeapRegion*
G1CollectedHeap::heap_region_containing(const void* addr) const {
  HeapRegion* hr = _hrs->addr_to_region(addr);
  // hr can be null if addr in perm_gen
  if (hr != NULL && hr->continuesHumongous()) {
    hr = hr->humongous_start_region();
  }
  return hr;
}

inline HeapRegion*
G1CollectedHeap::heap_region_containing_raw(const void* addr) const {
  assert(_g1_reserved.contains(addr), "invariant");
  size_t index = pointer_delta(addr, _g1_reserved.start(), 1)
                                        >> HeapRegion::LogOfHRGrainBytes;

  HeapRegion* res = _hrs->at(index);
  assert(res == _hrs->addr_to_region(addr), "sanity");
  return res;
}

inline bool G1CollectedHeap::obj_in_cs(oop obj) {
  HeapRegion* r = _hrs->addr_to_region(obj);
  return r != NULL && r->in_collection_set();
}

// See the comment in the .hpp file about the locking protocol and
// assumptions of this method (and other related ones).
inline HeapWord*
G1CollectedHeap::allocate_from_cur_alloc_region(HeapRegion* cur_alloc_region,
                                                size_t word_size,
                                                bool with_heap_lock) {
  assert_not_at_safepoint();
  assert(with_heap_lock == Heap_lock->owned_by_self(),
         "with_heap_lock and Heap_lock->owned_by_self() should be a tautology");
  assert(cur_alloc_region != NULL, "pre-condition of the method");
  assert(cur_alloc_region->is_young(),
         "we only support young current alloc regions");
  assert(!isHumongous(word_size), "allocate_from_cur_alloc_region() "
         "should not be used for humongous allocations");
  assert(!cur_alloc_region->isHumongous(), "Catch a regression of this bug.");

  assert(!cur_alloc_region->is_empty(),
         err_msg("region ["PTR_FORMAT","PTR_FORMAT"] should not be empty",
                 cur_alloc_region->bottom(), cur_alloc_region->end()));
  HeapWord* result = cur_alloc_region->par_allocate_no_bot_updates(word_size);
  if (result != NULL) {
    assert(is_in(result), "result should be in the heap");

    if (with_heap_lock) {
      Heap_lock->unlock();
    }
    assert_heap_not_locked();
    // Do the dirtying after we release the Heap_lock.
    dirty_young_block(result, word_size);
    return result;
  }

  if (with_heap_lock) {
    assert_heap_locked();
  } else {
    assert_heap_not_locked();
  }
  return NULL;
}

// See the comment in the .hpp file about the locking protocol and
// assumptions of this method (and other related ones).
inline HeapWord*
G1CollectedHeap::attempt_allocation(size_t word_size) {
  assert_heap_not_locked_and_not_at_safepoint();
  assert(!isHumongous(word_size), "attempt_allocation() should not be called "
         "for humongous allocation requests");

  HeapRegion* cur_alloc_region = _cur_alloc_region;
  if (cur_alloc_region != NULL) {
    HeapWord* result = allocate_from_cur_alloc_region(cur_alloc_region,
                                                   word_size,
                                                   false /* with_heap_lock */);
    assert_heap_not_locked();
    if (result != NULL) {
      return result;
    }
  }

  // Our attempt to allocate lock-free failed as the current
  // allocation region is either NULL or full. So, we'll now take the
  // Heap_lock and retry.
  Heap_lock->lock();

  HeapWord* result = attempt_allocation_locked(word_size);
  if (result != NULL) {
    assert_heap_not_locked();
    return result;
  }

  assert_heap_locked();
  return NULL;
}

inline void
G1CollectedHeap::retire_cur_alloc_region_common(HeapRegion* cur_alloc_region) {
  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(),
         "we only support young current alloc regions");

  // The region is guaranteed to be young
  g1_policy()->add_region_to_incremental_cset_lhs(cur_alloc_region);
  _summary_bytes_used += cur_alloc_region->used();
  _cur_alloc_region = NULL;
}

inline HeapWord*
G1CollectedHeap::attempt_allocation_locked(size_t word_size) {
  assert_heap_locked_and_not_at_safepoint();
  assert(!isHumongous(word_size), "attempt_allocation_locked() "
         "should not be called for humongous allocation requests");

  // First, reread the current alloc region and retry the allocation
  // in case somebody replaced it while we were waiting to get the
  // Heap_lock.
  HeapRegion* cur_alloc_region = _cur_alloc_region;
  if (cur_alloc_region != NULL) {
    HeapWord* result = allocate_from_cur_alloc_region(
                                                  cur_alloc_region, word_size,
                                                  true /* with_heap_lock */);
    if (result != NULL) {
      assert_heap_not_locked();
      return result;
    }

    // We failed to allocate out of the current alloc region, so let's
    // retire it before getting a new one.
    retire_cur_alloc_region(cur_alloc_region);
  }

  assert_heap_locked();
  // Try to get a new region and allocate out of it
  HeapWord* result = replace_cur_alloc_region_and_allocate(word_size,
                                                     false, /* at_safepoint */
                                                     true,  /* do_dirtying */
                                                     false  /* can_expand */);
  if (result != NULL) {
    assert_heap_not_locked();
    return result;
  }

  assert_heap_locked();
  return NULL;
}

// It dirties the cards that cover the block so that so that the post
// write barrier never queues anything when updating objects on this
// block. It is assumed (and in fact we assert) that the block
// belongs to a young region.
inline void
G1CollectedHeap::dirty_young_block(HeapWord* start, size_t word_size) {
  assert_heap_not_locked();

  // Assign the containing region to containing_hr so that we don't
  // have to keep calling heap_region_containing_raw() in the
  // asserts below.
  DEBUG_ONLY(HeapRegion* containing_hr = heap_region_containing_raw(start);)
  assert(containing_hr != NULL && start != NULL && word_size > 0,
         "pre-condition");
  assert(containing_hr->is_in(start), "it should contain start");
  assert(containing_hr->is_young(), "it should be young");
  assert(!containing_hr->isHumongous(), "it should not be humongous");

  HeapWord* end = start + word_size;
  assert(containing_hr->is_in(end - 1), "it should also contain end - 1");

  MemRegion mr(start, end);
  ((CardTableModRefBS*)_g1h->barrier_set())->dirty(mr);
}

inline RefToScanQueue* G1CollectedHeap::task_queue(int i) const {
  return _task_queues->queue(i);
}

inline  bool G1CollectedHeap::isMarkedPrev(oop obj) const {
  return _cm->prevMarkBitMap()->isMarked((HeapWord *)obj);
}

inline bool G1CollectedHeap::isMarkedNext(oop obj) const {
  return _cm->nextMarkBitMap()->isMarked((HeapWord *)obj);
}

#endif // SHARE_VM_GC_IMPLEMENTATION_G1_G1COLLECTEDHEAP_INLINE_HPP