1 /*
2  * Copyright (c) 2019, 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
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23  */
24 
25 #include "precompiled.hpp"
26 
27 #include "gc/shenandoah/shenandoahBarrierSetNMethod.hpp"
28 #include "gc/shenandoah/shenandoahClosures.inline.hpp"
29 #include "gc/shenandoah/shenandoahCodeRoots.hpp"
30 #include "gc/shenandoah/shenandoahHeap.inline.hpp"
31 #include "gc/shenandoah/shenandoahLock.hpp"
32 #include "gc/shenandoah/shenandoahNMethod.inline.hpp"
33 #include "gc/shenandoah/shenandoahThreadLocalData.hpp"
34 #include "memory/iterator.hpp"
35 #include "memory/resourceArea.hpp"
36 
nmethod_entry_barrier(nmethod * nm)37 bool ShenandoahBarrierSetNMethod::nmethod_entry_barrier(nmethod* nm) {
38   ShenandoahReentrantLock* lock = ShenandoahNMethod::lock_for_nmethod(nm);
39   assert(lock != NULL, "Must be");
40   ShenandoahReentrantLocker locker(lock);
41 
42   if (!is_armed(nm)) {
43     // Some other thread got here first and healed the oops
44     // and disarmed the nmethod.
45     return true;
46   }
47 
48   if (nm->is_unloading()) {
49     // We don't need to take the lock when unlinking nmethods from
50     // the Method, because it is only concurrently unlinked by
51     // the entry barrier, which acquires the per nmethod lock.
52     nm->unlink_from_method();
53 
54     // We can end up calling nmethods that are unloading
55     // since we clear compiled ICs lazily. Returning false
56     // will re-resovle the call and update the compiled IC.
57     return false;
58   }
59 
60   // Heal oops and disarm
61   ShenandoahNMethod::heal_nmethod(nm);
62   ShenandoahNMethod::disarm_nmethod(nm);
63   return true;
64 }
65 
disarmed_value() const66 int ShenandoahBarrierSetNMethod::disarmed_value() const {
67   return ShenandoahCodeRoots::disarmed_value();
68 }
69 
thread_disarmed_offset() const70 ByteSize ShenandoahBarrierSetNMethod::thread_disarmed_offset() const {
71   return ShenandoahThreadLocalData::disarmed_value_offset();
72 }
73 
disarmed_value_address() const74 int* ShenandoahBarrierSetNMethod::disarmed_value_address() const {
75   return ShenandoahCodeRoots::disarmed_value_address();
76 }
77