jdk8-mips64-public/hotspot: src/share/vm/gc_implementation/g1/g1CollectedHeap.inline.hpp@e7d0505c8a30 (annotated)

src/share/vm/gc_implementation/g1/g1CollectedHeap.inline.hpp@e7d0505c8a30 (annotated)

src/share/vm/gc_implementation/g1/g1CollectedHeap.inline.hpp

Fri, 10 Oct 2014 15:51:58 +0200

author: tschatzl
date: Fri, 10 Oct 2014 15:51:58 +0200
changeset 7257: e7d0505c8a30
parent 7159: e5668dcf12e9
child 7535: 7ae4e26cb1e0
child 7651: c132be0fb74d
permissions: -rw-r--r--

8059758: Footprint regressions with JDK-8038423
Summary: Changes in JDK-8038423 always initialize (zero out) virtual memory used for auxiliary data structures. This causes a footprint regression for G1 in startup benchmarks. This is because they do not touch that memory at all, so the operating system does not actually commit these pages. The fix is to, if the initialization value of the data structures matches the default value of just committed memory (=0), do not do anything.
Reviewed-by: jwilhelm, brutisso

 /*
  * Copyright (c) 2001, 2014, 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_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/g1AllocRegion.inline.hpp"
 #include "gc_implementation/g1/g1CollectorPolicy.hpp"
 #include "gc_implementation/g1/g1SATBCardTableModRefBS.hpp"
 #include "gc_implementation/g1/heapRegionManager.inline.hpp"
 #include "gc_implementation/g1/heapRegionSet.inline.hpp"
 #include "runtime/orderAccess.inline.hpp"
 #include "utilities/taskqueue.hpp"
 // Inline functions for G1CollectedHeap
 inline AllocationContextStats& G1CollectedHeap::allocation_context_stats() {
   return _allocation_context_stats;
 }
 // Return the region with the given index. It assumes the index is valid.
 inline HeapRegion* G1CollectedHeap::region_at(uint index) const { return _hrm.at(index); }
 inline uint G1CollectedHeap::addr_to_region(HeapWord* addr) const {
   assert(is_in_reserved(addr),
          err_msg("Cannot calculate region index for address "PTR_FORMAT" that is outside of the heap ["PTR_FORMAT", "PTR_FORMAT")",
                  p2i(addr), p2i(_reserved.start()), p2i(_reserved.end())));
   return (uint)(pointer_delta(addr, _reserved.start(), sizeof(uint8_t)) >> HeapRegion::LogOfHRGrainBytes);
 }
 inline HeapWord* G1CollectedHeap::bottom_addr_for_region(uint index) const {
   return _hrm.reserved().start() + index * HeapRegion::GrainWords;
 }
 template <class T>
 inline HeapRegion* G1CollectedHeap::heap_region_containing_raw(const T addr) const {
   assert(addr != NULL, "invariant");
   assert(is_in_g1_reserved((const void*) addr),
       err_msg("Address "PTR_FORMAT" is outside of the heap ranging from ["PTR_FORMAT" to "PTR_FORMAT")",
           p2i((void*)addr), p2i(g1_reserved().start()), p2i(g1_reserved().end())));
   return _hrm.addr_to_region((HeapWord*) addr);
 }
 template <class T>
 inline HeapRegion* G1CollectedHeap::heap_region_containing(const T addr) const {
   HeapRegion* hr = heap_region_containing_raw(addr);
   if (hr->continuesHumongous()) {
     return hr->humongous_start_region();
   }
   return hr;
 }
 inline void G1CollectedHeap::reset_gc_time_stamp() {
   _gc_time_stamp = 0;
   OrderAccess::fence();
   // Clear the cached CSet starting regions and time stamps.
   // Their validity is dependent on the GC timestamp.
   clear_cset_start_regions();
 }
 inline void G1CollectedHeap::increment_gc_time_stamp() {
   ++_gc_time_stamp;
   OrderAccess::fence();
 }
 inline void G1CollectedHeap::old_set_remove(HeapRegion* hr) {
   _old_set.remove(hr);
 }
 inline bool G1CollectedHeap::obj_in_cs(oop obj) {
   HeapRegion* r = _hrm.addr_to_region((HeapWord*) obj);
   return r != NULL && r->in_collection_set();
 }
 inline HeapWord* G1CollectedHeap::attempt_allocation(size_t word_size,
                                                      unsigned int* gc_count_before_ret,
                                                      int* gclocker_retry_count_ret) {
   assert_heap_not_locked_and_not_at_safepoint();
   assert(!isHumongous(word_size), "attempt_allocation() should not "
          "be called for humongous allocation requests");
   AllocationContext_t context = AllocationContext::current();
   HeapWord* result = _allocator->mutator_alloc_region(context)->attempt_allocation(word_size,
                                                                                    false /* bot_updates */);
   if (result == NULL) {
     result = attempt_allocation_slow(word_size,
                                      context,
                                      gc_count_before_ret,
                                      gclocker_retry_count_ret);
   }
   assert_heap_not_locked();
   if (result != NULL) {
     dirty_young_block(result, word_size);
   }
   return result;
 }
 inline HeapWord* G1CollectedHeap::survivor_attempt_allocation(size_t word_size,
                                                               AllocationContext_t context) {
   assert(!isHumongous(word_size),
          "we should not be seeing humongous-size allocations in this path");
   HeapWord* result = _allocator->survivor_gc_alloc_region(context)->attempt_allocation(word_size,
                                                                                        false /* bot_updates */);
   if (result == NULL) {
     MutexLockerEx x(FreeList_lock, Mutex::_no_safepoint_check_flag);
     result = _allocator->survivor_gc_alloc_region(context)->attempt_allocation_locked(word_size,
                                                                                       false /* bot_updates */);
   }
   if (result != NULL) {
     dirty_young_block(result, word_size);
   }
   return result;
 }
 inline HeapWord* G1CollectedHeap::old_attempt_allocation(size_t word_size,
                                                          AllocationContext_t context) {
   assert(!isHumongous(word_size),
          "we should not be seeing humongous-size allocations in this path");
   HeapWord* result = _allocator->old_gc_alloc_region(context)->attempt_allocation(word_size,
                                                                                   true /* bot_updates */);
   if (result == NULL) {
     MutexLockerEx x(FreeList_lock, Mutex::_no_safepoint_check_flag);
     result = _allocator->old_gc_alloc_region(context)->attempt_allocation_locked(word_size,
                                                                                  true /* bot_updates */);
   }
   return result;
 }
 // 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(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);
   g1_barrier_set()->g1_mark_as_young(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);
 }
 // This is a fast test on whether a reference points into the
 // collection set or not. Assume that the reference
 // points into the heap.
 inline bool G1CollectedHeap::is_in_cset(oop obj) {
   bool ret = _in_cset_fast_test.is_in_cset((HeapWord*)obj);
   // let's make sure the result is consistent with what the slower
   // test returns
   assert( ret || !obj_in_cs(obj), "sanity");
   assert(!ret ||  obj_in_cs(obj), "sanity");
   return ret;
 }
 bool G1CollectedHeap::is_in_cset_or_humongous(const oop obj) {
   return _in_cset_fast_test.is_in_cset_or_humongous((HeapWord*)obj);
 }
 G1CollectedHeap::in_cset_state_t G1CollectedHeap::in_cset_state(const oop obj) {
   return _in_cset_fast_test.at((HeapWord*)obj);
 }
 void G1CollectedHeap::register_humongous_region_with_in_cset_fast_test(uint index) {
   _in_cset_fast_test.set_humongous(index);
 }
 #ifndef PRODUCT
 // Support for G1EvacuationFailureALot
 inline bool
 G1CollectedHeap::evacuation_failure_alot_for_gc_type(bool gcs_are_young,
                                                      bool during_initial_mark,
                                                      bool during_marking) {
   bool res = false;
   if (during_marking) {
     res |= G1EvacuationFailureALotDuringConcMark;
   }
   if (during_initial_mark) {
     res |= G1EvacuationFailureALotDuringInitialMark;
   }
   if (gcs_are_young) {
     res |= G1EvacuationFailureALotDuringYoungGC;
   } else {
     // GCs are mixed
     res |= G1EvacuationFailureALotDuringMixedGC;
   }
   return res;
 }
 inline void
 G1CollectedHeap::set_evacuation_failure_alot_for_current_gc() {
   if (G1EvacuationFailureALot) {
     // Note we can't assert that _evacuation_failure_alot_for_current_gc
     // is clear here. It may have been set during a previous GC but that GC
     // did not copy enough objects (i.e. G1EvacuationFailureALotCount) to
     // trigger an evacuation failure and clear the flags and and counts.
     // Check if we have gone over the interval.
     const size_t gc_num = total_collections();
     const size_t elapsed_gcs = gc_num - _evacuation_failure_alot_gc_number;
     _evacuation_failure_alot_for_current_gc = (elapsed_gcs >= G1EvacuationFailureALotInterval);
     // Now check if G1EvacuationFailureALot is enabled for the current GC type.
     const bool gcs_are_young = g1_policy()->gcs_are_young();
     const bool during_im = g1_policy()->during_initial_mark_pause();
     const bool during_marking = mark_in_progress();
     _evacuation_failure_alot_for_current_gc &=
       evacuation_failure_alot_for_gc_type(gcs_are_young,
                                           during_im,
                                           during_marking);
   }
 }
 inline bool G1CollectedHeap::evacuation_should_fail() {
   if (!G1EvacuationFailureALot || !_evacuation_failure_alot_for_current_gc) {
     return false;
   }
   // G1EvacuationFailureALot is in effect for current GC
   // Access to _evacuation_failure_alot_count is not atomic;
   // the value does not have to be exact.
   if (++_evacuation_failure_alot_count < G1EvacuationFailureALotCount) {
     return false;
   }
   _evacuation_failure_alot_count = 0;
   return true;
 }
 inline void G1CollectedHeap::reset_evacuation_should_fail() {
   if (G1EvacuationFailureALot) {
     _evacuation_failure_alot_gc_number = total_collections();
     _evacuation_failure_alot_count = 0;
     _evacuation_failure_alot_for_current_gc = false;
   }
 }
 #endif  // #ifndef PRODUCT
 inline bool G1CollectedHeap::is_in_young(const oop obj) {
   if (obj == NULL) {
     return false;
   }
   return heap_region_containing(obj)->is_young();
 }
 // We don't need barriers for initializing stores to objects
 // in the young gen: for the SATB pre-barrier, there is no
 // pre-value that needs to be remembered; for the remembered-set
 // update logging post-barrier, we don't maintain remembered set
 // information for young gen objects.
 inline bool G1CollectedHeap::can_elide_initializing_store_barrier(oop new_obj) {
   return is_in_young(new_obj);
 }
 inline bool G1CollectedHeap::is_obj_dead(const oop obj) const {
   if (obj == NULL) {
     return false;
   }
   return is_obj_dead(obj, heap_region_containing(obj));
 }
 inline bool G1CollectedHeap::is_obj_ill(const oop obj) const {
   if (obj == NULL) {
     return false;
   }
   return is_obj_ill(obj, heap_region_containing(obj));
 }
 inline void G1CollectedHeap::set_humongous_is_live(oop obj) {
   uint region = addr_to_region((HeapWord*)obj);
   // We not only set the "live" flag in the humongous_is_live table, but also
   // reset the entry in the _in_cset_fast_test table so that subsequent references
   // to the same humongous object do not go into the slow path again.
   // This is racy, as multiple threads may at the same time enter here, but this
   // is benign.
   // During collection we only ever set the "live" flag, and only ever clear the
   // entry in the in_cset_fast_table.
   // We only ever evaluate the contents of these tables (in the VM thread) after
   // having synchronized the worker threads with the VM thread, or in the same
   // thread (i.e. within the VM thread).
   if (!_humongous_is_live.is_live(region)) {
     _humongous_is_live.set_live(region);
     _in_cset_fast_test.clear_humongous(region);
   }
 }
 #endif // SHARE_VM_GC_IMPLEMENTATION_G1_G1COLLECTEDHEAP_INLINE_HPP

Mercurial > jdk8-mips64-public > hotspot / annotate

src/share/vm/gc_implementation/g1/g1CollectedHeap.inline.hpp@e7d0505c8a30 (annotated)

src/share/vm/gc_implementation/g1/g1CollectedHeap.inline.hpp