jdk8-mips64-public/hotspot: src/share/vm/gc_implementation/g1/dirtyCardQueue.cpp@fa357420e7d2 (annotated)

src/share/vm/gc_implementation/g1/dirtyCardQueue.cpp@fa357420e7d2 (annotated)

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

Tue, 24 Nov 2009 15:19:30 -0800

author: johnc
date: Tue, 24 Nov 2009 15:19:30 -0800
changeset 1525: fa357420e7d2
parent 1320: 7f807f55161a
child 1546: 44f61c24ddab
permissions: -rw-r--r--

6899058: G1: Internal error in ptrQueue.cpp:201 in nightly tests
Summary: Fixes a race on the dirty card queue completed buffer list between worker thread(s) performing a flush of a deferred store barrier (enqueueing a newly completed buffer) and worker thread(s) in the RSet updating code claiming completed buffers. Removed the routine that removes elements from the completed update buffer queue using a CAS.
Reviewed-by: ysr, tonyp

 /*
  * Copyright 2001-2009 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/_dirtyCardQueue.cpp.incl"
 bool DirtyCardQueue::apply_closure(CardTableEntryClosure* cl,
                                    bool consume,
                                    size_t worker_i) {
   bool res = true;
   if (_buf != NULL) {
     res = apply_closure_to_buffer(cl, _buf, _index, _sz,
                                   consume,
                                   (int) worker_i);
     if (res && consume) _index = _sz;
   }
   return res;
 }
 bool DirtyCardQueue::apply_closure_to_buffer(CardTableEntryClosure* cl,
                                              void** buf,
                                              size_t index, size_t sz,
                                              bool consume,
                                              int worker_i) {
   if (cl == NULL) return true;
   for (size_t i = index; i < sz; i += oopSize) {
     int ind = byte_index_to_index((int)i);
     jbyte* card_ptr = (jbyte*)buf[ind];
     if (card_ptr != NULL) {
       // Set the entry to null, so we don't do it again (via the test
       // above) if we reconsider this buffer.
       if (consume) buf[ind] = NULL;
       if (!cl->do_card_ptr(card_ptr, worker_i)) return false;
     }
   }
   return true;
 }
 #ifdef _MSC_VER // the use of 'this' below gets a warning, make it go away
 #pragma warning( disable:4355 ) // 'this' : used in base member initializer list
 #endif // _MSC_VER
 DirtyCardQueueSet::DirtyCardQueueSet() :
   PtrQueueSet(true /*notify_when_complete*/),
   _closure(NULL),
   _shared_dirty_card_queue(this, true /*perm*/),
   _free_ids(NULL),
   _processed_buffers_mut(0), _processed_buffers_rs_thread(0)
 {
   _all_active = true;
 }
 // Determines how many mutator threads can process the buffers in parallel.
 size_t DirtyCardQueueSet::num_par_ids() {
   return os::processor_count();
 }
 void DirtyCardQueueSet::initialize(Monitor* cbl_mon, Mutex* fl_lock,
                                    int max_completed_queue,
                                    Mutex* lock, PtrQueueSet* fl_owner) {
   PtrQueueSet::initialize(cbl_mon, fl_lock, max_completed_queue, fl_owner);
   set_buffer_size(G1UpdateBufferSize);
   set_process_completed_threshold(G1UpdateBufferQueueProcessingThreshold);
   _shared_dirty_card_queue.set_lock(lock);
   _free_ids = new FreeIdSet((int) num_par_ids(), _cbl_mon);
 }
 void DirtyCardQueueSet::handle_zero_index_for_thread(JavaThread* t) {
   t->dirty_card_queue().handle_zero_index();
 }
 void DirtyCardQueueSet::set_closure(CardTableEntryClosure* closure) {
   _closure = closure;
 }
 void DirtyCardQueueSet::iterate_closure_all_threads(bool consume,
                                                     size_t worker_i) {
   assert(SafepointSynchronize::is_at_safepoint(), "Must be at safepoint.");
   for(JavaThread* t = Threads::first(); t; t = t->next()) {
     bool b = t->dirty_card_queue().apply_closure(_closure, consume);
     guarantee(b, "Should not be interrupted.");
   }
   bool b = shared_dirty_card_queue()->apply_closure(_closure,
                                                     consume,
                                                     worker_i);
   guarantee(b, "Should not be interrupted.");
 }
 bool DirtyCardQueueSet::mut_process_buffer(void** buf) {
   // Used to determine if we had already claimed a par_id
   // before entering this method.
   bool already_claimed = false;
   // We grab the current JavaThread.
   JavaThread* thread = JavaThread::current();
   // We get the the number of any par_id that this thread
   // might have already claimed.
   int worker_i = thread->get_claimed_par_id();
   // If worker_i is not -1 then the thread has already claimed
   // a par_id. We make note of it using the already_claimed value
   if (worker_i != -1) {
     already_claimed = true;
   } else {
     // Otherwise we need to claim a par id
     worker_i = _free_ids->claim_par_id();
     // And store the par_id value in the thread
     thread->set_claimed_par_id(worker_i);
   }
   bool b = false;
   if (worker_i != -1) {
     b = DirtyCardQueue::apply_closure_to_buffer(_closure, buf, 0,
                                                 _sz, true, worker_i);
     if (b) Atomic::inc(&_processed_buffers_mut);
     // If we had not claimed an id before entering the method
     // then we must release the id.
     if (!already_claimed) {
       // we release the id
       _free_ids->release_par_id(worker_i);
       // and set the claimed_id in the thread to -1
       thread->set_claimed_par_id(-1);
     }
   }
   return b;
 }
 DirtyCardQueueSet::CompletedBufferNode*
 DirtyCardQueueSet::get_completed_buffer(int stop_at) {
   CompletedBufferNode* nd = NULL;
   MutexLockerEx x(_cbl_mon, Mutex::_no_safepoint_check_flag);
   if ((int)_n_completed_buffers <= stop_at) {
     _process_completed = false;
     return NULL;
   }
   if (_completed_buffers_head != NULL) {
     nd = _completed_buffers_head;
     _completed_buffers_head = nd->next;
     if (_completed_buffers_head == NULL)
       _completed_buffers_tail = NULL;
     _n_completed_buffers--;
   }
   debug_only(assert_completed_buffer_list_len_correct_locked());
   return nd;
 }
 bool DirtyCardQueueSet::
 apply_closure_to_completed_buffer_helper(int worker_i,
                                          CompletedBufferNode* nd) {
   if (nd != NULL) {
     bool b =
       DirtyCardQueue::apply_closure_to_buffer(_closure, nd->buf,
                                               nd->index, _sz,
                                               true, worker_i);
     void** buf = nd->buf;
     size_t index = nd->index;
     delete nd;
     if (b) {
       deallocate_buffer(buf);
       return true;  // In normal case, go on to next buffer.
     } else {
       enqueue_complete_buffer(buf, index, true);
       return false;
     }
   } else {
     return false;
   }
 }
 bool DirtyCardQueueSet::apply_closure_to_completed_buffer(int worker_i,
                                                           int stop_at,
                                                           bool during_pause)
 {
   assert(!during_pause || stop_at == 0, "Should not leave any completed buffers during a pause");
   CompletedBufferNode* nd = get_completed_buffer(stop_at);
   bool res = apply_closure_to_completed_buffer_helper(worker_i, nd);
   if (res) Atomic::inc(&_processed_buffers_rs_thread);
   return res;
 }
 void DirtyCardQueueSet::apply_closure_to_all_completed_buffers() {
   CompletedBufferNode* nd = _completed_buffers_head;
   while (nd != NULL) {
     bool b =
       DirtyCardQueue::apply_closure_to_buffer(_closure, nd->buf, 0, _sz,
                                               false);
     guarantee(b, "Should not stop early.");
     nd = nd->next;
   }
 }
 void DirtyCardQueueSet::abandon_logs() {
   assert(SafepointSynchronize::is_at_safepoint(), "Must be at safepoint.");
   CompletedBufferNode* buffers_to_delete = NULL;
   {
     MutexLockerEx x(_cbl_mon, Mutex::_no_safepoint_check_flag);
     while (_completed_buffers_head != NULL) {
       CompletedBufferNode* nd = _completed_buffers_head;
       _completed_buffers_head = nd->next;
       nd->next = buffers_to_delete;
       buffers_to_delete = nd;
     }
     _n_completed_buffers = 0;
     _completed_buffers_tail = NULL;
     debug_only(assert_completed_buffer_list_len_correct_locked());
   }
   while (buffers_to_delete != NULL) {
     CompletedBufferNode* nd = buffers_to_delete;
     buffers_to_delete = nd->next;
     deallocate_buffer(nd->buf);
     delete nd;
   }
   // Since abandon is done only at safepoints, we can safely manipulate
   // these queues.
   for (JavaThread* t = Threads::first(); t; t = t->next()) {
     t->dirty_card_queue().reset();
   }
   shared_dirty_card_queue()->reset();
 }
 void DirtyCardQueueSet::concatenate_logs() {
   // Iterate over all the threads, if we find a partial log add it to
   // the global list of logs.  Temporarily turn off the limit on the number
   // of outstanding buffers.
   int save_max_completed_queue = _max_completed_queue;
   _max_completed_queue = max_jint;
   assert(SafepointSynchronize::is_at_safepoint(), "Must be at safepoint.");
   for (JavaThread* t = Threads::first(); t; t = t->next()) {
     DirtyCardQueue& dcq = t->dirty_card_queue();
     if (dcq.size() != 0) {
       void **buf = t->dirty_card_queue().get_buf();
       // We must NULL out the unused entries, then enqueue.
       for (size_t i = 0; i < t->dirty_card_queue().get_index(); i += oopSize) {
         buf[PtrQueue::byte_index_to_index((int)i)] = NULL;
       }
       enqueue_complete_buffer(dcq.get_buf(), dcq.get_index());
       dcq.reinitialize();
     }
   }
   if (_shared_dirty_card_queue.size() != 0) {
     enqueue_complete_buffer(_shared_dirty_card_queue.get_buf(),
                             _shared_dirty_card_queue.get_index());
     _shared_dirty_card_queue.reinitialize();
   }
   // Restore the completed buffer queue limit.
   _max_completed_queue = save_max_completed_queue;
 }

Mercurial > jdk8-mips64-public > hotspot / annotate

src/share/vm/gc_implementation/g1/dirtyCardQueue.cpp@fa357420e7d2 (annotated)

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