jdk8-mips64-public/hotspot: src/share/vm/gc_implementation/g1/g1SATBCardTableModRefBS.cpp@7df07d855c8e (annotated)

src/share/vm/gc_implementation/g1/g1SATBCardTableModRefBS.cpp@7df07d855c8e (annotated)

src/share/vm/gc_implementation/g1/g1SATBCardTableModRefBS.cpp

Mon, 21 Jul 2014 09:59:46 +0200

author: tschatzl
date: Mon, 21 Jul 2014 09:59:46 +0200
changeset 7007: 7df07d855c8e
parent 6989: e5035defa3c4
child 7051: 1f1d373cd044
permissions: -rw-r--r--

8048085: Aborting marking just before remark results in useless additional clearing of the next mark bitmap
Summary: Skip clearing the next bitmap if we just recently aborted since the full GC already clears this bitmap.
Reviewed-by: brutisso

 /*
  * Copyright (c) 2001, 2013, 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.
  *
  */
 #include "precompiled.hpp"
 #include "gc_implementation/g1/g1SATBCardTableModRefBS.hpp"
 #include "gc_implementation/g1/heapRegion.hpp"
 #include "gc_implementation/g1/satbQueue.hpp"
 #include "runtime/mutexLocker.hpp"
 #include "runtime/orderAccess.inline.hpp"
 #include "runtime/thread.inline.hpp"
 G1SATBCardTableModRefBS::G1SATBCardTableModRefBS(MemRegion whole_heap,
                                                  int max_covered_regions) :
     CardTableModRefBSForCTRS(whole_heap, max_covered_regions)
 {
   _kind = G1SATBCT;
 }
 void G1SATBCardTableModRefBS::enqueue(oop pre_val) {
   // Nulls should have been already filtered.
   assert(pre_val->is_oop(true), "Error");
   if (!JavaThread::satb_mark_queue_set().is_active()) return;
   Thread* thr = Thread::current();
   if (thr->is_Java_thread()) {
     JavaThread* jt = (JavaThread*)thr;
     jt->satb_mark_queue().enqueue(pre_val);
   } else {
     MutexLockerEx x(Shared_SATB_Q_lock, Mutex::_no_safepoint_check_flag);
     JavaThread::satb_mark_queue_set().shared_satb_queue()->enqueue(pre_val);
   }
 }
 template <class T> void
 G1SATBCardTableModRefBS::write_ref_array_pre_work(T* dst, int count) {
   if (!JavaThread::satb_mark_queue_set().is_active()) return;
   T* elem_ptr = dst;
   for (int i = 0; i < count; i++, elem_ptr++) {
     T heap_oop = oopDesc::load_heap_oop(elem_ptr);
     if (!oopDesc::is_null(heap_oop)) {
       enqueue(oopDesc::decode_heap_oop_not_null(heap_oop));
     }
   }
 }
 void G1SATBCardTableModRefBS::write_ref_array_pre(oop* dst, int count, bool dest_uninitialized) {
   if (!dest_uninitialized) {
     write_ref_array_pre_work(dst, count);
   }
 }
 void G1SATBCardTableModRefBS::write_ref_array_pre(narrowOop* dst, int count, bool dest_uninitialized) {
   if (!dest_uninitialized) {
     write_ref_array_pre_work(dst, count);
   }
 }
 bool G1SATBCardTableModRefBS::mark_card_deferred(size_t card_index) {
   jbyte val = _byte_map[card_index];
   // It's already processed
   if ((val & (clean_card_mask_val() | deferred_card_val())) == deferred_card_val()) {
     return false;
   }
   if  (val == g1_young_gen) {
     // the card is for a young gen region. We don't need to keep track of all pointers into young
     return false;
   }
   // Cached bit can be installed either on a clean card or on a claimed card.
   jbyte new_val = val;
   if (val == clean_card_val()) {
     new_val = (jbyte)deferred_card_val();
   } else {
     if (val & claimed_card_val()) {
       new_val = val | (jbyte)deferred_card_val();
     }
   }
   if (new_val != val) {
     Atomic::cmpxchg(new_val, &_byte_map[card_index], val);
   }
   return true;
 }
 void G1SATBCardTableModRefBS::g1_mark_as_young(const MemRegion& mr) {
   jbyte *const first = byte_for(mr.start());
   jbyte *const last = byte_after(mr.last());
   // Below we may use an explicit loop instead of memset() because on
   // certain platforms memset() can give concurrent readers phantom zeros.
   if (UseMemSetInBOT) {
     memset(first, g1_young_gen, last - first);
   } else {
     for (jbyte* i = first; i < last; i++) {
       *i = g1_young_gen;
     }
   }
 }
 #ifndef PRODUCT
 void G1SATBCardTableModRefBS::verify_g1_young_region(MemRegion mr) {
   verify_region(mr, g1_young_gen,  true);
 }
 #endif
 G1SATBCardTableLoggingModRefBS::
 G1SATBCardTableLoggingModRefBS(MemRegion whole_heap,
                                int max_covered_regions) :
   G1SATBCardTableModRefBS(whole_heap, max_covered_regions),
   _dcqs(JavaThread::dirty_card_queue_set())
 {
   _kind = G1SATBCTLogging;
 }
 void
 G1SATBCardTableLoggingModRefBS::write_ref_field_work(void* field,
                                                      oop new_val,
                                                      bool release) {
   volatile jbyte* byte = byte_for(field);
   if (*byte == g1_young_gen) {
     return;
   }
   OrderAccess::storeload();
   if (*byte != dirty_card) {
     *byte = dirty_card;
     Thread* thr = Thread::current();
     if (thr->is_Java_thread()) {
       JavaThread* jt = (JavaThread*)thr;
       jt->dirty_card_queue().enqueue(byte);
     } else {
       MutexLockerEx x(Shared_DirtyCardQ_lock,
                       Mutex::_no_safepoint_check_flag);
       _dcqs.shared_dirty_card_queue()->enqueue(byte);
     }
   }
 }
 void
 G1SATBCardTableLoggingModRefBS::write_ref_field_static(void* field,
                                                        oop new_val) {
   uintptr_t field_uint = (uintptr_t)field;
   uintptr_t new_val_uint = cast_from_oop<uintptr_t>(new_val);
   uintptr_t comb = field_uint ^ new_val_uint;
   comb = comb >> HeapRegion::LogOfHRGrainBytes;
   if (comb == 0) return;
   if (new_val == NULL) return;
   // Otherwise, log it.
   G1SATBCardTableLoggingModRefBS* g1_bs =
     (G1SATBCardTableLoggingModRefBS*)Universe::heap()->barrier_set();
   g1_bs->write_ref_field_work(field, new_val);
 }
 void
 G1SATBCardTableLoggingModRefBS::invalidate(MemRegion mr, bool whole_heap) {
   volatile jbyte* byte = byte_for(mr.start());
   jbyte* last_byte = byte_for(mr.last());
   Thread* thr = Thread::current();
   if (whole_heap) {
     while (byte <= last_byte) {
       *byte = dirty_card;
       byte++;
     }
   } else {
     // skip all consecutive young cards
     for (; byte <= last_byte && *byte == g1_young_gen; byte++);
     if (byte <= last_byte) {
       OrderAccess::storeload();
       // Enqueue if necessary.
       if (thr->is_Java_thread()) {
         JavaThread* jt = (JavaThread*)thr;
         for (; byte <= last_byte; byte++) {
           if (*byte == g1_young_gen) {
             continue;
           }
           if (*byte != dirty_card) {
             *byte = dirty_card;
             jt->dirty_card_queue().enqueue(byte);
           }
         }
       } else {
         MutexLockerEx x(Shared_DirtyCardQ_lock,
                         Mutex::_no_safepoint_check_flag);
         for (; byte <= last_byte; byte++) {
           if (*byte == g1_young_gen) {
             continue;
           }
           if (*byte != dirty_card) {
             *byte = dirty_card;
             _dcqs.shared_dirty_card_queue()->enqueue(byte);
           }
         }
       }
     }
   }
 }

Mercurial > jdk8-mips64-public > hotspot / annotate

src/share/vm/gc_implementation/g1/g1SATBCardTableModRefBS.cpp@7df07d855c8e (annotated)

src/share/vm/gc_implementation/g1/g1SATBCardTableModRefBS.cpp