< prev index next >

src/hotspot/share/jfr/recorder/checkpoint/types/traceid/jfrTraceIdEpoch.cpp

Print this page

 1 /*
 2  * Copyright (c) 2016, 2019, 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  */
24 
25 #include "precompiled.hpp"
26 #include "jfr/recorder/checkpoint/types/traceid/jfrTraceIdEpoch.hpp"
27 #include "runtime/safepoint.hpp"
28 

29 JfrSignal JfrTraceIdEpoch::_tag_state;
30 bool JfrTraceIdEpoch::_epoch_state = false;
31 bool JfrTraceIdEpoch::_synchronizing = false;
32 
33 void JfrTraceIdEpoch::begin_epoch_shift() {
34   assert(SafepointSynchronize::is_at_safepoint(), "invariant");
35   _synchronizing = true;
36   OrderAccess::fence();
37 }
38 
39 void JfrTraceIdEpoch::end_epoch_shift() {
40   assert(SafepointSynchronize::is_at_safepoint(), "invariant");
41   assert(_synchronizing, "invariant");
42   _epoch_state = !_epoch_state;





43   OrderAccess::storestore();
44   _synchronizing = false;
45 }
46 

 1 /*
 2  * Copyright (c) 2016, 2020, 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  */
24 
25 #include "precompiled.hpp"
26 #include "jfr/recorder/checkpoint/types/traceid/jfrTraceIdEpoch.hpp"
27 #include "runtime/safepoint.hpp"
28 
29 u2 JfrTraceIdEpoch::_generation = 0;
30 JfrSignal JfrTraceIdEpoch::_tag_state;
31 bool JfrTraceIdEpoch::_epoch_state = false;
32 bool JfrTraceIdEpoch::_synchronizing = false;
33 
34 void JfrTraceIdEpoch::begin_epoch_shift() {
35   assert(SafepointSynchronize::is_at_safepoint(), "invariant");
36   _synchronizing = true;
37   OrderAccess::fence();
38 }
39 
40 void JfrTraceIdEpoch::end_epoch_shift() {
41   assert(SafepointSynchronize::is_at_safepoint(), "invariant");
42   assert(_synchronizing, "invariant");
43   _epoch_state = !_epoch_state;
44   ++_generation;
45   if (0 == _generation) {
46     ++_generation;
47   }
48   assert(_generation != 0, "invariant");
49   OrderAccess::storestore();
50   _synchronizing = false;
51 }
52 
< prev index next >