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 PASSED 0
46 #define FAILED 2
47
48 #define TEST_CLASS "GetOwnedMonitorInfoTest"
49
50 static volatile jboolean event_has_posted = JNI_FALSE;
51 static volatile jint status = PASSED;
52
53 static jint Agent_Initialize(JavaVM *jvm, char *options, void *reserved);
54
55 static void ShowErrorMessage(jvmtiEnv *jvmti, jvmtiError errCode, const char *message) {
56 char *errMsg;
57 jvmtiError result;
58
59 result = (*jvmti)->GetErrorName(jvmti, errCode, &errMsg);
60 if (result == JVMTI_ERROR_NONE) {
61 fprintf(stderr, "%s: %s (%d)\n", message, errMsg, errCode);
62 (*jvmti)->Deallocate(jvmti, (unsigned char *)errMsg);
63 } else {
64 fprintf(stderr, "%s (%d)\n", message, errCode);
65 }
66 }
67
68 static jboolean CheckLockObject(JNIEnv *env, jobject monitor) {
69 jclass testClass;
70
71 testClass = (*env)->FindClass(env, TEST_CLASS);
72 if (testClass == NULL) {
73 fprintf(stderr, "MonitorContendedEnter: " TEST_CLASS " not found\n");
74 status = FAILED;
75 event_has_posted = JNI_TRUE;
76 return JNI_FALSE;
77 }
78
79 return (*env)->IsInstanceOf(env, monitor, testClass);
80 }
81
82 JNIEXPORT void JNICALL
83 MonitorContendedEnter(jvmtiEnv *jvmti, JNIEnv *env, jthread thread, jobject monitor) {
84 jvmtiError err;
85 jvmtiThreadInfo threadInfo;
86 jint monitorCount;
87 jobject *ownedMonitors;
88
89 if (CheckLockObject(env, monitor) == JNI_FALSE) {
90 return;
91 }
92
93 err = (*jvmti)->GetThreadInfo(jvmti, thread, &threadInfo);
94 if (err != JVMTI_ERROR_NONE) {
95 ShowErrorMessage(jvmti, err,
96 "MonitorContendedEnter: error in JVMTI GetThreadInfo");
97 status = FAILED;
98 event_has_posted = JNI_TRUE;
99 return;
100 }
101 err = (*jvmti)->GetOwnedMonitorInfo(jvmti, thread, &monitorCount, &ownedMonitors);
102 if (err != JVMTI_ERROR_NONE) {
103 ShowErrorMessage(jvmti, err,
104 "MonitorContendedEnter: error in JVMTI GetOwnedMonitorInfo");
105 status = FAILED;
106 event_has_posted = JNI_TRUE;
107 return;
108 }
109
110 printf("MonitorContendedEnter: %s owns %d monitor(s)\n",
111 threadInfo.name, monitorCount);
112
113 (*jvmti)->Deallocate(jvmti, (unsigned char *)ownedMonitors);
114 (*jvmti)->Deallocate(jvmti, (unsigned char *)threadInfo.name);
115
116 if (monitorCount != 0) {
117 fprintf(stderr, "MonitorContendedEnter: FAIL: monitorCount should be zero.\n");
118 status = FAILED;
119 }
120
121 event_has_posted = JNI_TRUE;
122 }
123
124 JNIEXPORT void JNICALL
125 MonitorContendedEntered(jvmtiEnv *jvmti, JNIEnv *env, jthread thread, jobject monitor) {
126 jvmtiError err;
127 jvmtiThreadInfo threadInfo;
128 jint monitorCount;
129 jobject *ownedMonitors;
130
131 if (CheckLockObject(env, monitor) == JNI_FALSE) {
132 return;
133 }
134
135 err = (*jvmti)->GetThreadInfo(jvmti, thread, &threadInfo);
136 if (err != JVMTI_ERROR_NONE) {
137 ShowErrorMessage(jvmti, err,
138 "MonitorContendedEntered: error in JVMTI GetThreadInfo");
139 status = FAILED;
140 return;
141 }
142 err = (*jvmti)->GetOwnedMonitorInfo(jvmti, thread, &monitorCount, &ownedMonitors);
143 if (err != JVMTI_ERROR_NONE) {
144 ShowErrorMessage(jvmti, err,
145 "MonitorContendedEntered: error in JVMTI GetOwnedMonitorInfo");
146 status = FAILED;
147 return;
148 }
149
150 printf("MonitorContendedEntered: %s owns %d monitor(s)\n",
151 threadInfo.name, monitorCount);
152
153 (*jvmti)->Deallocate(jvmti, (unsigned char *)ownedMonitors);
154 (*jvmti)->Deallocate(jvmti, (unsigned char *)threadInfo.name);
155
156 if (monitorCount != 1) {
157 fprintf(stderr, "MonitorContendedEnter: FAIL: monitorCount should be one.\n");
158 status = FAILED;
159 }
160 }
161
162 JNIEXPORT jint JNICALL
163 Agent_OnLoad(JavaVM *jvm, char *options, void *reserved) {
164 return Agent_Initialize(jvm, options, reserved);
165 }
166
167 JNIEXPORT jint JNICALL
168 Agent_OnAttach(JavaVM *jvm, char *options, void *reserved) {
169 return Agent_Initialize(jvm, options, reserved);
170 }
171
172 JNIEXPORT jint JNICALL
173 JNI_OnLoad(JavaVM *jvm, void *reserved) {
174 return JNI_VERSION_1_8;
175 }
176
177 static
178 jint Agent_Initialize(JavaVM *jvm, char *options, void *reserved) {
179 jint res;
180 jvmtiError err;
181 jvmtiEnv *jvmti;
182 jvmtiCapabilities caps;
183 jvmtiEventCallbacks callbacks;
184
185 printf("Agent_OnLoad started\n");
186
187 res = JNI_ENV_PTR(jvm)->GetEnv(JNI_ENV_ARG(jvm, (void **) &jvmti),
188 JVMTI_VERSION_1);
189 if (res != JNI_OK || jvmti == NULL) {
190 fprintf(stderr, "Error: wrong result of a valid call to GetEnv!\n");
191 return JNI_ERR;
192 }
193
194 err = (*jvmti)->GetPotentialCapabilities(jvmti, &caps);
195 if (err != JVMTI_ERROR_NONE) {
196 ShowErrorMessage(jvmti, err,
197 "Agent_OnLoad: error in JVMTI GetPotentialCapabilities");
198 return JNI_ERR;
199 }
200
201 err = (*jvmti)->AddCapabilities(jvmti, &caps);
202 if (err != JVMTI_ERROR_NONE) {
203 ShowErrorMessage(jvmti, err,
204 "Agent_OnLoad: error in JVMTI AddCapabilities");
205 return JNI_ERR;
206 }
207
208 err = (*jvmti)->GetCapabilities(jvmti, &caps);
209 if (err != JVMTI_ERROR_NONE) {
210 ShowErrorMessage(jvmti, err,
211 "Agent_OnLoad: error in JVMTI GetCapabilities");
212 return JNI_ERR;
213 }
214
215 if (!caps.can_generate_monitor_events) {
216 fprintf(stderr, "Warning: Monitor events are not implemented\n");
217 return JNI_ERR;
218 }
219 if (!caps.can_get_owned_monitor_info) {
220 fprintf(stderr, "Warning: GetOwnedMonitorInfo is not implemented\n");
221 return JNI_ERR;
222 }
223
224 callbacks.MonitorContendedEnter = &MonitorContendedEnter;
225 callbacks.MonitorContendedEntered = &MonitorContendedEntered;
226
227 err = (*jvmti)->SetEventCallbacks(jvmti, &callbacks, sizeof(jvmtiEventCallbacks));
228 if (err != JVMTI_ERROR_NONE) {
229 ShowErrorMessage(jvmti, err,
230 "Agent_OnLoad: error in JVMTI SetEventCallbacks");
231 return JNI_ERR;
232 }
233
234 err = (*jvmti)->SetEventNotificationMode(jvmti, JVMTI_ENABLE,
235 JVMTI_EVENT_MONITOR_CONTENDED_ENTER, NULL);
236 if (err != JVMTI_ERROR_NONE) {
237 ShowErrorMessage(jvmti, err,
238 "Agent_OnLoad: error in JVMTI SetEventNotificationMode #1");
239 return JNI_ERR;
240 }
241 err = (*jvmti)->SetEventNotificationMode(jvmti, JVMTI_ENABLE,
242 JVMTI_EVENT_MONITOR_CONTENDED_ENTERED, NULL);
243 if (err != JVMTI_ERROR_NONE) {
244 ShowErrorMessage(jvmti, err,
245 "Agent_OnLoad: error in JVMTI SetEventNotificationMode #2");
246 return JNI_ERR;
247 }
248 printf("Agent_OnLoad finished\n");
249 return JNI_OK;
250 }
251
252 JNIEXPORT jint JNICALL
253 Java_GetOwnedMonitorInfoTest_check(JNIEnv *env, jclass cls) {
254 return status;
255 }
256
257 JNIEXPORT jboolean JNICALL
258 Java_GetOwnedMonitorInfoTest_hasEventPosted(JNIEnv *env, jclass cls) {
259 return event_has_posted;
260 }
261
262 #ifdef __cplusplus
263 }
264 #endif