1 /*
2 * Copyright (c) 2017, 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 #include <stdio.h>
25 #include <string.h>
26 #include "jvmti.h"
27 #include "jni.h"
28
29 #ifdef __cplusplus
30 extern "C" {
31 #endif
32
33 #ifndef JNI_ENV_ARG
34
35 #ifdef __cplusplus
36 #define JNI_ENV_ARG(x, y) y
37 #define JNI_ENV_PTR(x) x
38 #else
39 #define JNI_ENV_ARG(x,y) x, y
40 #define JNI_ENV_PTR(x) (*x)
41 #endif
42
43 #endif
44
45 #define TranslateError(err) "JVMTI error"
46
47 #define PASSED 0
48 #define FAILED 2
49
50 static jint status = PASSED;
51
52 static jint Agent_Initialize(JavaVM *jvm, char *options, void *reserved);
53
54 JNIEXPORT void JNICALL
55 MonitorContendedEnter(jvmtiEnv *jvmti, JNIEnv *env, jthread thread, jobject monitor) {
56 jvmtiThreadInfo threadInfo;
57 jint monitorCount;
58 jobject *ownedMonitors;
59
60 (*jvmti)->GetThreadInfo(jvmti, thread, &threadInfo);
61 (*jvmti)->GetOwnedMonitorInfo(jvmti, thread, &monitorCount, &ownedMonitors);
62
63 printf("MonitorContendedEnter: %s owns %d monitor(s)\n",
64 threadInfo.name, monitorCount);
65
66 (*jvmti)->Deallocate(jvmti, (unsigned char *)ownedMonitors);
67 (*jvmti)->Deallocate(jvmti, (unsigned char *)threadInfo.name);
68
69 if (monitorCount != 0) {
70 status = FAILED;
71 }
72 }
73
74 JNIEXPORT void JNICALL
75 MonitorContendedEntered(jvmtiEnv *jvmti, JNIEnv *env, jthread thread, jobject monitor) {
76 jvmtiThreadInfo threadInfo;
77 jint monitorCount;
78 jobject *ownedMonitors;
79
80 (*jvmti)->GetThreadInfo(jvmti, thread, &threadInfo);
81 (*jvmti)->GetOwnedMonitorInfo(jvmti, thread, &monitorCount, &ownedMonitors);
82
83 printf("MonitorContendedEntered: %s owns %d monitor(s)\n",
84 threadInfo.name, monitorCount);
85
86 (*jvmti)->Deallocate(jvmti, (unsigned char *)ownedMonitors);
87 (*jvmti)->Deallocate(jvmti, (unsigned char *)threadInfo.name);
88
89 if (monitorCount != 1) {
90 status = FAILED;
91 }
92 }
93
94 JNIEXPORT jint JNICALL
95 Agent_OnLoad(JavaVM *jvm, char *options, void *reserved) {
96 return Agent_Initialize(jvm, options, reserved);
97 }
98
99 JNIEXPORT jint JNICALL
100 Agent_OnAttach(JavaVM *jvm, char *options, void *reserved) {
101 return Agent_Initialize(jvm, options, reserved);
102 }
103
104 JNIEXPORT jint JNICALL
105 JNI_OnLoad(JavaVM *jvm, void *reserved) {
106 return JNI_VERSION_1_8;
107 }
108
109 static
110 jint Agent_Initialize(JavaVM *jvm, char *options, void *reserved) {
111 jint res;
112 jvmtiError err;
113 jvmtiEnv *jvmti;
114 jvmtiCapabilities caps;
115 jvmtiEventCallbacks callbacks;
116
117 printf("Agent_OnLoad started\n");
118
119 res = JNI_ENV_PTR(jvm)->GetEnv(JNI_ENV_ARG(jvm, (void **) &jvmti),
120 JVMTI_VERSION_1);
121 if (res != JNI_OK || jvmti == NULL) {
122 printf(" Error: wrong result of a valid call to GetEnv!\n");
123 return JNI_ERR;
124 }
125
126 err = (*jvmti)->GetPotentialCapabilities(jvmti, &caps);
127 if (err != JVMTI_ERROR_NONE) {
128 printf("Agent_OnLoad: error in JVMTI GetPotentialCapabilities: %d\n", err);
129 return JNI_ERR;
130 }
131
132 err = (*jvmti)->AddCapabilities(jvmti, &caps);
133 if (err != JVMTI_ERROR_NONE) {
134 printf("Agent_OnLoad: error in JVMTI AddCapabilities: %d\n", err);
135 }
136
137 err = (*jvmti)->GetCapabilities(jvmti, &caps);
138 if (err != JVMTI_ERROR_NONE) {
139 printf("Agent_OnLoad: error in JVMTI GetCapabilities: %d\n", err);
140 return JNI_ERR;
141 }
142
143 if (!caps.can_generate_monitor_events) {
144 printf("Warning: Monitor events are not implemented\n");
145 }
146 if (!caps.can_get_owned_monitor_info) {
147 printf("Warning: GetOwnedMonitorInfo is not implemented\n");
148 }
149
150 callbacks.MonitorContendedEnter = &MonitorContendedEnter;
151 callbacks.MonitorContendedEntered = &MonitorContendedEntered;
152
153 err = (*jvmti)->SetEventCallbacks(jvmti, &callbacks, sizeof(jvmtiEventCallbacks));
154 if (err != JVMTI_ERROR_NONE) {
155 printf("Agent_OnLoad: error in JVMTI SetEventCallbacks: %d\n", err);
156 }
157
158 err = (*jvmti)->SetEventNotificationMode(jvmti, JVMTI_ENABLE,
159 JVMTI_EVENT_MONITOR_CONTENDED_ENTER, NULL);
160 if (err != JVMTI_ERROR_NONE) {
161 printf("Agent_OnLoad: error in JVMTI SetEventNotificationMode #1: %d\n", err);
162 }
163 err = (*jvmti)->SetEventNotificationMode(jvmti, JVMTI_ENABLE,
164 JVMTI_EVENT_MONITOR_CONTENDED_ENTERED, NULL);
165 if (err != JVMTI_ERROR_NONE) {
166 printf("Agent_OnLoad: error in JVMTI SetEventNotificationMode #2: %d\n", err);
167 }
168 printf("Agent_OnLoad finished\n");
169 return JNI_OK;
170 }
171
172 JNIEXPORT jint JNICALL
173 Java_GetOwnedMonitorInfoTest_check(JNIEnv *env, jclass cls) {
174 return status;
175 }
176
177 #ifdef __cplusplus
178 }
179 #endif