1/*
2 * Copyright (c) 2013, 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#ifndef SHARE_JFR_RECORDER_SERVICE_JFRPOSTBOX_HPP
26#define SHARE_JFR_RECORDER_SERVICE_JFRPOSTBOX_HPP
27
28#include "jfr/utilities/jfrAllocation.hpp"
29
30#define MSGBIT(e) (1<<(e))
31
32enum JFR_Msg {
33 MSG_ALL_MSGS = -1,
34 MSG_CLONE_IN_MEMORY = 0,
35 MSG_START,
36 MSG_STOP,
37 MSG_ROTATE,
38 MSG_FULLBUFFER,
39 MSG_CHECKPOINT,
40 MSG_WAKEUP,
41 MSG_SHUTDOWN,
42 MSG_VM_ERROR,
43 MSG_DEADBUFFER,
44 MSG_NO_OF_MSGS
45};
46
47/**
48 * Jfr messaging.
49 *
50 * Synchronous messages (posting thread waits for message completion):
51 *
52 * MSG_CLONE_IN_MEMORY (0) ; MSGBIT(MSG_CLONE_IN_MEMORY) == (1 << 0) == 0x1
53 * MSG_START(1) ; MSGBIT(MSG_START) == (1 << 0x1) == 0x2
54 * MSG_STOP (2) ; MSGBIT(MSG_STOP) == (1 << 0x2) == 0x4
55 * MSG_ROTATE (3) ; MSGBIT(MSG_ROTATE) == (1 << 0x3) == 0x8
56 * MSG_VM_ERROR (8) ; MSGBIT(MSG_VM_ERROR) == (1 << 8) == 0x100
57 *
58 * Asynchronous messages (posting thread returns immediately upon deposit):
59 *
60 * MSG_FULLBUFFER (4) ; MSGBIT(MSG_FULLBUFFER) == (1 << 0x4) == 0x10
61 * MSG_CHECKPOINT (5) ; MSGBIT(CHECKPOINT) == (1 << 5) == 0x20
62 * MSG_WAKEUP (6) ; MSGBIT(WAKEUP) == (1 << 6) == 0x40
63 * MSG_SHUTDOWN (7) ; MSGBIT(MSG_SHUTDOWN) == (1 << 7) == 0x80
64 * MSG_DEADBUFFER (9) ; MSGBIT(MSG_DEADBUFFER) == (1 << 9) == 0x200
65 */
66
67class JfrPostBox : public JfrCHeapObj {
68 friend class JfrRecorder;
69 public:
70 void post(JFR_Msg msg);
71
72 private:
73 uintptr_t _msg_read_serial;
74 uintptr_t _msg_handled_serial;
75 volatile int _messages;
76 bool _has_waiters;
77
78 JfrPostBox();
79 static JfrPostBox& instance();
80 static JfrPostBox* create();
81 static void destroy();
82
83 void asynchronous_post(int msg);
84 void synchronous_post(int msg);
85 void deposit(int new_messages);
86 bool is_message_processed(uintptr_t serial_id) const;
87
88 friend void recorderthread_entry(JavaThread*, Thread*);
89 // for the friend declaration above
90 bool is_empty() const;
91 int collect();
92 bool check_waiters(int messages) const;
93 void notify_waiters();
94 void notify_collection_stop();
95};
96
97#endif // SHARE_JFR_RECORDER_SERVICE_JFRPOSTBOX_HPP
98