1 /* Copyright (C) 2017 The Android Open Source Project 2 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. 3 * 4 * This file implements interfaces from the file jvmti.h. This implementation 5 * is licensed under the same terms as the file jvmti.h. The 6 * copyright and license information for the file jvmti.h follows. 7 * 8 * Copyright (c) 2003, 2011, Oracle and/or its affiliates. All rights reserved. 9 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. 10 * 11 * This code is free software; you can redistribute it and/or modify it 12 * under the terms of the GNU General Public License version 2 only, as 13 * published by the Free Software Foundation. Oracle designates this 14 * particular file as subject to the "Classpath" exception as provided 15 * by Oracle in the LICENSE file that accompanied this code. 16 * 17 * This code is distributed in the hope that it will be useful, but WITHOUT 18 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 19 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License 20 * version 2 for more details (a copy is included in the LICENSE file that 21 * accompanied this code). 22 * 23 * You should have received a copy of the GNU General Public License version 24 * 2 along with this work; if not, write to the Free Software Foundation, 25 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. 26 * 27 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA 28 * or visit www.oracle.com if you need additional information or have any 29 * questions. 30 */ 31 32 #ifndef ART_RUNTIME_OPENJDKJVMTI_TI_THREAD_H_ 33 #define ART_RUNTIME_OPENJDKJVMTI_TI_THREAD_H_ 34 35 #include "jni.h" 36 #include "jvmti.h" 37 38 #include "base/mutex.h" 39 40 namespace art { 41 class ArtField; 42 class Thread; 43 } // namespace art 44 45 namespace openjdkjvmti { 46 47 class EventHandler; 48 49 class ThreadUtil { 50 public: 51 static void Register(EventHandler* event_handler); 52 static void Unregister(); 53 54 // To be called when it is safe to cache data. 55 static void CacheData(); 56 57 // Handle a jvmtiEnv going away. 58 static void RemoveEnvironment(jvmtiEnv* env); 59 60 static jvmtiError GetAllThreads(jvmtiEnv* env, jint* threads_count_ptr, jthread** threads_ptr); 61 62 static jvmtiError GetCurrentThread(jvmtiEnv* env, jthread* thread_ptr); 63 64 static jvmtiError GetThreadInfo(jvmtiEnv* env, jthread thread, jvmtiThreadInfo* info_ptr); 65 66 static jvmtiError GetThreadState(jvmtiEnv* env, jthread thread, jint* thread_state_ptr); 67 68 static jvmtiError SetThreadLocalStorage(jvmtiEnv* env, jthread thread, const void* data); 69 static jvmtiError GetThreadLocalStorage(jvmtiEnv* env, jthread thread, void** data_ptr); 70 71 static jvmtiError RunAgentThread(jvmtiEnv* env, 72 jthread thread, 73 jvmtiStartFunction proc, 74 const void* arg, 75 jint priority); 76 77 static jvmtiError SuspendThread(jvmtiEnv* env, jthread thread); 78 static jvmtiError ResumeThread(jvmtiEnv* env, jthread thread); 79 80 static jvmtiError SuspendThreadList(jvmtiEnv* env, 81 jint request_count, 82 const jthread* threads, 83 jvmtiError* results); 84 static jvmtiError ResumeThreadList(jvmtiEnv* env, 85 jint request_count, 86 const jthread* threads, 87 jvmtiError* results); 88 89 private: 90 // We need to make sure only one thread tries to suspend threads at a time so we can get the 91 // 'suspend-only-once' behavior the spec requires. Internally, ART considers suspension to be a 92 // counted state, allowing a single thread to be suspended multiple times by different users. This 93 // makes mapping into the JVMTI idea of thread suspension difficult. We have decided to split the 94 // difference and ensure that JVMTI tries to treat suspension as the boolean flag as much as 95 // possible with the suspend/resume methods but only do best effort. On the other hand 96 // GetThreadState will be totally accurate as much as possible. This means that calling 97 // ResumeThread on a thread that has state JVMTI_THREAD_STATE_SUSPENDED will not necessarily 98 // cause the thread to wake up if the thread is suspended for the debugger or gc or something. 99 static jvmtiError SuspendSelf(art::Thread* self) 100 REQUIRES(!art::Locks::mutator_lock_, !art::Locks::user_code_suspension_lock_); 101 static jvmtiError SuspendOther(art::Thread* self, jthread target_jthread, art::Thread* target) 102 REQUIRES(!art::Locks::mutator_lock_, !art::Locks::user_code_suspension_lock_); 103 104 static art::ArtField* context_class_loader_; 105 }; 106 107 } // namespace openjdkjvmti 108 109 #endif // ART_RUNTIME_OPENJDKJVMTI_TI_THREAD_H_ 110