Mercurial > jdk8-mips64-public > hotspot / file revision

 /*

  * 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.

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  */

 #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));

     }

   }

 }

 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);

           }

         }

       }

     }

   }

 }