1 /*
2 * Copyright (c) 2021, Red Hat, Inc. 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 */
24
25 #include "precompiled.hpp"
26
27 #include "compiler/oopMap.hpp"
28 #include "gc/shared/workerThread.hpp"
29 #include "gc/shenandoah/shenandoahClosures.inline.hpp"
30 #include "gc/shenandoah/shenandoahGC.hpp"
31 #include "gc/shenandoah/shenandoahHeap.hpp"
32 #include "gc/shenandoah/shenandoahPhaseTimings.hpp"
33 #include "gc/shenandoah/shenandoahRootProcessor.inline.hpp"
34 #include "gc/shenandoah/shenandoahUtils.hpp"
35
36 const char* ShenandoahGC::degen_point_to_string(ShenandoahDegenPoint point) {
37 switch(point) {
38 case _degenerated_unset:
39 return "<UNSET>";
40 case _degenerated_outside_cycle:
41 return "Outside of Cycle";
42 case _degenerated_roots:
43 return "Roots";
44 case _degenerated_mark:
45 return "Mark";
46 case _degenerated_evac:
47 return "Evacuation";
48 case _degenerated_updaterefs:
49 return "Update References";
50 default:
51 ShouldNotReachHere();
52 return "ERROR";
53 }
54 }
55
56 class ShenandoahUpdateRootsTask : public WorkerTask {
57 private:
58 ShenandoahRootUpdater* _root_updater;
59 bool _check_alive;
60 public:
61 ShenandoahUpdateRootsTask(ShenandoahRootUpdater* root_updater, bool check_alive) :
62 WorkerTask("Shenandoah Update Roots"),
63 _root_updater(root_updater),
64 _check_alive(check_alive){
65 }
66
67 void work(uint worker_id) {
68 assert(ShenandoahSafepoint::is_at_shenandoah_safepoint(), "Must be at a safepoint");
69 ShenandoahParallelWorkerSession worker_session(worker_id);
70
71 ShenandoahNonConcUpdateRefsClosure cl;
72 if (_check_alive) {
73 ShenandoahForwardedIsAliveClosure is_alive;
74 _root_updater->roots_do<ShenandoahForwardedIsAliveClosure, ShenandoahNonConcUpdateRefsClosure>(worker_id, &is_alive, &cl);
75 } else {
76 AlwaysTrueClosure always_true;
77 _root_updater->roots_do<AlwaysTrueClosure, ShenandoahNonConcUpdateRefsClosure>(worker_id, &always_true, &cl);
78 }
79 }
80 };
81
82 void ShenandoahGC::update_roots(bool full_gc) {
83 assert(ShenandoahSafepoint::is_at_shenandoah_safepoint(), "Must be at a safepoint");
84 assert(ShenandoahHeap::heap()->is_full_gc_in_progress() ||
85 ShenandoahHeap::heap()->is_degenerated_gc_in_progress(),
86 "Only for degenerated GC and full GC");
87
88 bool check_alive = !full_gc;
89 ShenandoahPhaseTimings::Phase p = full_gc ?
90 ShenandoahPhaseTimings::full_gc_update_roots :
91 ShenandoahPhaseTimings::degen_gc_update_roots;
92
93 ShenandoahGCPhase phase(p);
94 #if COMPILER2_OR_JVMCI
95 DerivedPointerTable::clear();
96 #endif
97
98 ShenandoahHeap* const heap = ShenandoahHeap::heap();
99 WorkerThreads* workers = heap->workers();
100 uint nworkers = workers->active_workers();
101
102 ShenandoahRootUpdater root_updater(nworkers, p);
103 ShenandoahUpdateRootsTask update_roots(&root_updater, check_alive);
104 workers->run_task(&update_roots);
105
106 #if COMPILER2_OR_JVMCI
107 DerivedPointerTable::update_pointers();
108 #endif
109 }