src/share/vm/gc_implementation/g1/g1OopClosures.inline.hpp

Mon, 07 Jul 2014 10:12:40 +0200

author
stefank
date
Mon, 07 Jul 2014 10:12:40 +0200
changeset 6992
2c6ef90f030a
parent 6937
b0c374311c4e
child 7010
a3953c777565
permissions
-rw-r--r--

8049421: G1 Class Unloading after completing a concurrent mark cycle
Reviewed-by: tschatzl, ehelin, brutisso, coleenp, roland, iveresov
Contributed-by: stefan.karlsson@oracle.com, mikael.gerdin@oracle.com

     1 /*
     2  * Copyright (c) 2001, 2014, Oracle and/or its affiliates. All rights reserved.
     3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
     4  *
     5  * This code is free software; you can redistribute it and/or modify it
     6  * under the terms of the GNU General Public License version 2 only, as
     7  * published by the Free Software Foundation.
     8  *
     9  * This code is distributed in the hope that it will be useful, but WITHOUT
    10  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
    11  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
    12  * version 2 for more details (a copy is included in the LICENSE file that
    13  * accompanied this code).
    14  *
    15  * You should have received a copy of the GNU General Public License version
    16  * 2 along with this work; if not, write to the Free Software Foundation,
    17  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
    18  *
    19  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
    20  * or visit www.oracle.com if you need additional information or have any
    21  * questions.
    22  *
    23  */
    25 #ifndef SHARE_VM_GC_IMPLEMENTATION_G1_G1OOPCLOSURES_INLINE_HPP
    26 #define SHARE_VM_GC_IMPLEMENTATION_G1_G1OOPCLOSURES_INLINE_HPP
    28 #include "gc_implementation/g1/concurrentMark.inline.hpp"
    29 #include "gc_implementation/g1/g1CollectedHeap.hpp"
    30 #include "gc_implementation/g1/g1OopClosures.hpp"
    31 #include "gc_implementation/g1/g1ParScanThreadState.inline.hpp"
    32 #include "gc_implementation/g1/g1RemSet.hpp"
    33 #include "gc_implementation/g1/g1RemSet.inline.hpp"
    34 #include "gc_implementation/g1/heapRegionRemSet.hpp"
    35 #include "memory/iterator.inline.hpp"
    36 #include "runtime/prefetch.inline.hpp"
    38 /*
    39  * This really ought to be an inline function, but apparently the C++
    40  * compiler sometimes sees fit to ignore inline declarations.  Sigh.
    41  */
    43 template <class T>
    44 inline void FilterIntoCSClosure::do_oop_nv(T* p) {
    45   T heap_oop = oopDesc::load_heap_oop(p);
    46   if (!oopDesc::is_null(heap_oop) &&
    47       _g1->obj_in_cs(oopDesc::decode_heap_oop_not_null(heap_oop))) {
    48     _oc->do_oop(p);
    49   }
    50 }
    52 template <class T>
    53 inline void FilterOutOfRegionClosure::do_oop_nv(T* p) {
    54   T heap_oop = oopDesc::load_heap_oop(p);
    55   if (!oopDesc::is_null(heap_oop)) {
    56     HeapWord* obj_hw = (HeapWord*)oopDesc::decode_heap_oop_not_null(heap_oop);
    57     if (obj_hw < _r_bottom || obj_hw >= _r_end) {
    58       _oc->do_oop(p);
    59     }
    60   }
    61 }
    63 // This closure is applied to the fields of the objects that have just been copied.
    64 template <class T>
    65 inline void G1ParScanClosure::do_oop_nv(T* p) {
    66   T heap_oop = oopDesc::load_heap_oop(p);
    68   if (!oopDesc::is_null(heap_oop)) {
    69     oop obj = oopDesc::decode_heap_oop_not_null(heap_oop);
    70     if (_g1->in_cset_fast_test(obj)) {
    71       // We're not going to even bother checking whether the object is
    72       // already forwarded or not, as this usually causes an immediate
    73       // stall. We'll try to prefetch the object (for write, given that
    74       // we might need to install the forwarding reference) and we'll
    75       // get back to it when pop it from the queue
    76       Prefetch::write(obj->mark_addr(), 0);
    77       Prefetch::read(obj->mark_addr(), (HeapWordSize*2));
    79       // slightly paranoid test; I'm trying to catch potential
    80       // problems before we go into push_on_queue to know where the
    81       // problem is coming from
    82       assert((obj == oopDesc::load_decode_heap_oop(p)) ||
    83              (obj->is_forwarded() &&
    84                  obj->forwardee() == oopDesc::load_decode_heap_oop(p)),
    85              "p should still be pointing to obj or to its forwardee");
    87       _par_scan_state->push_on_queue(p);
    88     } else {
    89       _par_scan_state->update_rs(_from, p, _worker_id);
    90     }
    91   }
    92 }
    94 template <class T>
    95 inline void G1ParPushHeapRSClosure::do_oop_nv(T* p) {
    96   T heap_oop = oopDesc::load_heap_oop(p);
    98   if (!oopDesc::is_null(heap_oop)) {
    99     oop obj = oopDesc::decode_heap_oop_not_null(heap_oop);
   100     if (_g1->in_cset_fast_test(obj)) {
   101       Prefetch::write(obj->mark_addr(), 0);
   102       Prefetch::read(obj->mark_addr(), (HeapWordSize*2));
   104       // Place on the references queue
   105       _par_scan_state->push_on_queue(p);
   106     }
   107   }
   108 }
   110 template <class T>
   111 inline void G1CMOopClosure::do_oop_nv(T* p) {
   112   oop obj = oopDesc::load_decode_heap_oop(p);
   113   if (_cm->verbose_high()) {
   114     gclog_or_tty->print_cr("[%u] we're looking at location "
   115                            "*"PTR_FORMAT" = "PTR_FORMAT,
   116                            _task->worker_id(), p2i(p), p2i((void*) obj));
   117   }
   118   _task->deal_with_reference(obj);
   119 }
   121 template <class T>
   122 inline void G1RootRegionScanClosure::do_oop_nv(T* p) {
   123   T heap_oop = oopDesc::load_heap_oop(p);
   124   if (!oopDesc::is_null(heap_oop)) {
   125     oop obj = oopDesc::decode_heap_oop_not_null(heap_oop);
   126     HeapRegion* hr = _g1h->heap_region_containing((HeapWord*) obj);
   127     if (hr != NULL) {
   128       _cm->grayRoot(obj, obj->size(), _worker_id, hr);
   129     }
   130   }
   131 }
   133 template <class T>
   134 inline void G1Mux2Closure::do_oop_nv(T* p) {
   135   // Apply first closure; then apply the second.
   136   _c1->do_oop(p);
   137   _c2->do_oop(p);
   138 }
   140 template <class T>
   141 inline void G1TriggerClosure::do_oop_nv(T* p) {
   142   // Record that this closure was actually applied (triggered).
   143   _triggered = true;
   144 }
   146 template <class T>
   147 inline void G1InvokeIfNotTriggeredClosure::do_oop_nv(T* p) {
   148   if (!_trigger_cl->triggered()) {
   149     _oop_cl->do_oop(p);
   150   }
   151 }
   153 template <class T>
   154 inline void G1UpdateRSOrPushRefOopClosure::do_oop_nv(T* p) {
   155   oop obj = oopDesc::load_decode_heap_oop(p);
   156 #ifdef ASSERT
   157   // can't do because of races
   158   // assert(obj == NULL || obj->is_oop(), "expected an oop");
   160   // Do the safe subset of is_oop
   161   if (obj != NULL) {
   162 #ifdef CHECK_UNHANDLED_OOPS
   163     oopDesc* o = obj.obj();
   164 #else
   165     oopDesc* o = obj;
   166 #endif // CHECK_UNHANDLED_OOPS
   167     assert((intptr_t)o % MinObjAlignmentInBytes == 0, "not oop aligned");
   168     assert(Universe::heap()->is_in_reserved(obj), "must be in heap");
   169   }
   170 #endif // ASSERT
   172   assert(_from != NULL, "from region must be non-NULL");
   173   assert(_from->is_in_reserved(p), "p is not in from");
   175   HeapRegion* to = _g1->heap_region_containing(obj);
   176   if (to != NULL && _from != to) {
   177     // The _record_refs_into_cset flag is true during the RSet
   178     // updating part of an evacuation pause. It is false at all
   179     // other times:
   180     //  * rebuilding the rembered sets after a full GC
   181     //  * during concurrent refinement.
   182     //  * updating the remembered sets of regions in the collection
   183     //    set in the event of an evacuation failure (when deferred
   184     //    updates are enabled).
   186     if (_record_refs_into_cset && to->in_collection_set()) {
   187       // We are recording references that point into the collection
   188       // set and this particular reference does exactly that...
   189       // If the referenced object has already been forwarded
   190       // to itself, we are handling an evacuation failure and
   191       // we have already visited/tried to copy this object
   192       // there is no need to retry.
   193       if (!self_forwarded(obj)) {
   194         assert(_push_ref_cl != NULL, "should not be null");
   195         // Push the reference in the refs queue of the G1ParScanThreadState
   196         // instance for this worker thread.
   197         _push_ref_cl->do_oop(p);
   198       }
   200       // Deferred updates to the CSet are either discarded (in the normal case),
   201       // or processed (if an evacuation failure occurs) at the end
   202       // of the collection.
   203       // See G1RemSet::cleanup_after_oops_into_collection_set_do().
   204       return;
   205     }
   207     // We either don't care about pushing references that point into the
   208     // collection set (i.e. we're not during an evacuation pause) _or_
   209     // the reference doesn't point into the collection set. Either way
   210     // we add the reference directly to the RSet of the region containing
   211     // the referenced object.
   212     assert(to->rem_set() != NULL, "Need per-region 'into' remsets.");
   213     to->rem_set()->add_reference(p, _worker_i);
   214   }
   215 }
   217 #endif // SHARE_VM_GC_IMPLEMENTATION_G1_G1OOPCLOSURES_INLINE_HPP

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