| /* |
| * Copyright (c) 2019, Oracle and/or its affiliates. All rights reserved. |
| * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. |
| * |
| * This code is free software; you can redistribute it and/or modify it |
| * under the terms of the GNU General Public License version 2 only, as |
| * published by the Free Software Foundation. |
| * |
| * This code is distributed in the hope that it will be useful, but WITHOUT |
| * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or |
| * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License |
| * version 2 for more details (a copy is included in the LICENSE file that |
| * accompanied this code). |
| * |
| * You should have received a copy of the GNU General Public License version |
| * 2 along with this work; if not, write to the Free Software Foundation, |
| * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. |
| * |
| * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA |
| * or visit www.oracle.com if you need additional information or have any |
| * questions. |
| */ |
| |
| #include <stdio.h> |
| #include <stdlib.h> |
| #include <string.h> |
| |
| #include "jvmti.h" |
| #include "jni.h" |
| |
| #ifdef __cplusplus |
| extern "C" { |
| #endif |
| |
| static int events; |
| static int total_events = 0; |
| |
| void JNICALL CompiledMethodLoad(jvmtiEnv* jvmti, jmethodID method, |
| jint code_size, const void* code_addr, |
| jint map_length, const jvmtiAddrLocationMap* map, |
| const void* compile_info) { |
| events++; |
| total_events++; |
| } |
| |
| // Continuously generate CompiledMethodLoad events for all currently compiled methods |
| void JNICALL GenerateEventsThread(jvmtiEnv* jvmti, JNIEnv* jni, void* arg) { |
| (*jvmti)->SetEventNotificationMode(jvmti, JVMTI_ENABLE, JVMTI_EVENT_COMPILED_METHOD_LOAD, NULL); |
| int count = 0; |
| |
| while (1) { |
| events = 0; |
| (*jvmti)->GenerateEvents(jvmti, JVMTI_EVENT_COMPILED_METHOD_LOAD); |
| if (events != 0 && ++count == 200) { |
| printf("Generated %d events\n", events); |
| count = 0; |
| } |
| } |
| } |
| |
| // As soon as VM starts, run a separate Agent thread that will generate CompiledMethodLoad events |
| void JNICALL VMInit(jvmtiEnv* jvmti, JNIEnv* jni, jthread thread) { |
| jclass thread_class = (*jni)->FindClass(jni, "java/lang/Thread"); |
| jmethodID thread_constructor = (*jni)->GetMethodID(jni, thread_class, "<init>", "()V"); |
| jthread agent_thread = (*jni)->NewObject(jni, thread_class, thread_constructor); |
| |
| (*jvmti)->RunAgentThread(jvmti, agent_thread, GenerateEventsThread, NULL, JVMTI_THREAD_NORM_PRIORITY); |
| } |
| |
| JNIEXPORT |
| jint JNICALL Agent_OnLoad(JavaVM* vm, char* options, void* reserved) { |
| jvmtiEnv* jvmti; |
| (*vm)->GetEnv(vm, (void**)&jvmti, JVMTI_VERSION_1_0); |
| |
| jvmtiCapabilities capabilities; |
| memset(&capabilities, 0, sizeof(capabilities)); |
| |
| capabilities.can_generate_compiled_method_load_events = 1; |
| (*jvmti)->AddCapabilities(jvmti, &capabilities); |
| |
| jvmtiEventCallbacks callbacks; |
| memset(&callbacks, 0, sizeof(callbacks)); |
| callbacks.VMInit = VMInit; |
| callbacks.CompiledMethodLoad = CompiledMethodLoad; |
| (*jvmti)->SetEventCallbacks(jvmti, &callbacks, sizeof(callbacks)); |
| (*jvmti)->SetEventNotificationMode(jvmti, JVMTI_ENABLE, JVMTI_EVENT_VM_INIT, NULL); |
| |
| return 0; |
| } |
| |
| #ifdef __cplusplus |
| } |
| #endif |
| |