jdk8-mips64-public/hotspot: src/share/vm/gc_implementation/g1/heapRegion.inline.hpp@64bf7c8270cb (annotated)

src/share/vm/gc_implementation/g1/heapRegion.inline.hpp@64bf7c8270cb (annotated)

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

Mon, 12 Mar 2012 14:59:00 -0700

author: johnc
date: Mon, 12 Mar 2012 14:59:00 -0700
changeset 3666: 64bf7c8270cb
parent 3464: eff609af17d7
child 3731: 8a2e5a6a19a4
permissions: -rw-r--r--

7147724: G1: hang in SurrogateLockerThread::manipulatePLL
Summary: Attempting to initiate a marking cycle when allocating a humongous object can, if a marking cycle is successfully initiated by another thread, result in the allocating thread spinning until the marking cycle is complete. Eliminate a deadlock between the main ConcurrentMarkThread, the SurrogateLocker thread, the VM thread, and a mutator thread waiting on the SecondaryFreeList_lock (while free regions are going to become available) by not manipulating the pending list lock during the prologue and epilogue of the cleanup pause.
Reviewed-by: brutisso, jcoomes, tonyp

 /*
  * Copyright (c) 2001, 2012, 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
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 #ifndef SHARE_VM_GC_IMPLEMENTATION_G1_HEAPREGION_INLINE_HPP
 #define SHARE_VM_GC_IMPLEMENTATION_G1_HEAPREGION_INLINE_HPP
 inline HeapWord* G1OffsetTableContigSpace::allocate(size_t size) {
   HeapWord* res = ContiguousSpace::allocate(size);
   if (res != NULL) {
     _offsets.alloc_block(res, size);
   }
   return res;
 }
 // Because of the requirement of keeping "_offsets" up to date with the
 // allocations, we sequentialize these with a lock.  Therefore, best if
 // this is used for larger LAB allocations only.
 inline HeapWord* G1OffsetTableContigSpace::par_allocate(size_t size) {
   MutexLocker x(&_par_alloc_lock);
   // Given that we take the lock no need to use par_allocate() here.
   HeapWord* res = ContiguousSpace::allocate(size);
   if (res != NULL) {
     _offsets.alloc_block(res, size);
   }
   return res;
 }
 inline HeapWord* G1OffsetTableContigSpace::block_start(const void* p) {
   return _offsets.block_start(p);
 }
 inline HeapWord*
 G1OffsetTableContigSpace::block_start_const(const void* p) const {
   return _offsets.block_start_const(p);
 }
 inline void HeapRegion::note_start_of_marking() {
   init_top_at_conc_mark_count();
   _next_marked_bytes = 0;
   _next_top_at_mark_start = top();
 }
 inline void HeapRegion::note_end_of_marking() {
   _prev_top_at_mark_start = _next_top_at_mark_start;
   _prev_marked_bytes = _next_marked_bytes;
   _next_marked_bytes = 0;
   assert(_prev_marked_bytes <=
          (size_t) pointer_delta(prev_top_at_mark_start(), bottom()) *
          HeapWordSize, "invariant");
 }
 inline void HeapRegion::note_start_of_copying(bool during_initial_mark) {
   if (is_survivor()) {
     // This is how we always allocate survivors.
     assert(_next_top_at_mark_start == bottom(), "invariant");
   } else {
     if (during_initial_mark) {
       // During initial-mark we'll explicitly mark any objects on old
       // regions that are pointed to by roots. Given that explicit
       // marks only make sense under NTAMS it'd be nice if we could
       // check that condition if we wanted to. Given that we don't
       // know where the top of this region will end up, we simply set
       // NTAMS to the end of the region so all marks will be below
       // NTAMS. We'll set it to the actual top when we retire this region.
       _next_top_at_mark_start = end();
     } else {
       // We could have re-used this old region as to-space over a
       // couple of GCs since the start of the concurrent marking
       // cycle. This means that [bottom,NTAMS) will contain objects
       // copied up to and including initial-mark and [NTAMS, top)
       // will contain objects copied during the concurrent marking cycle.
       assert(top() >= _next_top_at_mark_start, "invariant");
     }
   }
 }
 inline void HeapRegion::note_end_of_copying(bool during_initial_mark) {
   if (is_survivor()) {
     // This is how we always allocate survivors.
     assert(_next_top_at_mark_start == bottom(), "invariant");
   } else {
     if (during_initial_mark) {
       // See the comment for note_start_of_copying() for the details
       // on this.
       assert(_next_top_at_mark_start == end(), "pre-condition");
       _next_top_at_mark_start = top();
     } else {
       // See the comment for note_start_of_copying() for the details
       // on this.
       assert(top() >= _next_top_at_mark_start, "invariant");
     }
   }
 }
 #endif // SHARE_VM_GC_IMPLEMENTATION_G1_HEAPREGION_INLINE_HPP

Mercurial > jdk8-mips64-public > hotspot / annotate

src/share/vm/gc_implementation/g1/heapRegion.inline.hpp@64bf7c8270cb (annotated)

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