1 /* 2 * Copyright (C) 2008 The Android Open Source Project 3 * 4 * Licensed under the Apache License, Version 2.0 (the "License"); 5 * you may not use this file except in compliance with the License. 6 * You may obtain a copy of the License at 7 * 8 * http://www.apache.org/licenses/LICENSE-2.0 9 * 10 * Unless required by applicable law or agreed to in writing, software 11 * distributed under the License is distributed on an "AS IS" BASIS, 12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 13 * See the License for the specific language governing permissions and 14 * limitations under the License. 15 */ 16 17 #include "java_lang_Thread.h" 18 19 #include "common_throws.h" 20 #include "debugger.h" 21 #include "jni_internal.h" 22 #include "monitor.h" 23 #include "mirror/object.h" 24 #include "scoped_fast_native_object_access.h" 25 #include "scoped_thread_state_change.h" 26 #include "ScopedUtfChars.h" 27 #include "thread.h" 28 #include "thread_list.h" 29 #include "verify_object-inl.h" 30 31 namespace art { 32 33 static jobject Thread_currentThread(JNIEnv* env, jclass) { 34 ScopedFastNativeObjectAccess soa(env); 35 return soa.AddLocalReference<jobject>(soa.Self()->GetPeer()); 36 } 37 38 static jboolean Thread_interrupted(JNIEnv* env, jclass) { 39 return static_cast<JNIEnvExt*>(env)->self->Interrupted() ? JNI_TRUE : JNI_FALSE; 40 } 41 42 static jboolean Thread_isInterrupted(JNIEnv* env, jobject java_thread) { 43 ScopedFastNativeObjectAccess soa(env); 44 MutexLock mu(soa.Self(), *Locks::thread_list_lock_); 45 Thread* thread = Thread::FromManagedThread(soa, java_thread); 46 return (thread != nullptr) ? thread->IsInterrupted() : JNI_FALSE; 47 } 48 49 static void Thread_nativeCreate(JNIEnv* env, jclass, jobject java_thread, jlong stack_size, 50 jboolean daemon) { 51 Thread::CreateNativeThread(env, java_thread, stack_size, daemon == JNI_TRUE); 52 } 53 54 static jint Thread_nativeGetStatus(JNIEnv* env, jobject java_thread, jboolean has_been_started) { 55 // Ordinals from Java's Thread.State. 56 const jint kJavaNew = 0; 57 const jint kJavaRunnable = 1; 58 const jint kJavaBlocked = 2; 59 const jint kJavaWaiting = 3; 60 const jint kJavaTimedWaiting = 4; 61 const jint kJavaTerminated = 5; 62 63 ScopedObjectAccess soa(env); 64 ThreadState internal_thread_state = (has_been_started ? kTerminated : kStarting); 65 MutexLock mu(soa.Self(), *Locks::thread_list_lock_); 66 Thread* thread = Thread::FromManagedThread(soa, java_thread); 67 if (thread != nullptr) { 68 internal_thread_state = thread->GetState(); 69 } 70 switch (internal_thread_state) { 71 case kTerminated: return kJavaTerminated; 72 case kRunnable: return kJavaRunnable; 73 case kTimedWaiting: return kJavaTimedWaiting; 74 case kSleeping: return kJavaTimedWaiting; 75 case kBlocked: return kJavaBlocked; 76 case kWaiting: return kJavaWaiting; 77 case kStarting: return kJavaNew; 78 case kNative: return kJavaRunnable; 79 case kWaitingForGcToComplete: return kJavaWaiting; 80 case kWaitingPerformingGc: return kJavaWaiting; 81 case kWaitingForCheckPointsToRun: return kJavaWaiting; 82 case kWaitingForDebuggerSend: return kJavaWaiting; 83 case kWaitingForDebuggerToAttach: return kJavaWaiting; 84 case kWaitingInMainDebuggerLoop: return kJavaWaiting; 85 case kWaitingForDebuggerSuspension: return kJavaWaiting; 86 case kWaitingForDeoptimization: return kJavaWaiting; 87 case kWaitingForGetObjectsAllocated: return kJavaWaiting; 88 case kWaitingForJniOnLoad: return kJavaWaiting; 89 case kWaitingForSignalCatcherOutput: return kJavaWaiting; 90 case kWaitingInMainSignalCatcherLoop: return kJavaWaiting; 91 case kWaitingForMethodTracingStart: return kJavaWaiting; 92 case kWaitingForVisitObjects: return kJavaWaiting; 93 case kSuspended: return kJavaRunnable; 94 // Don't add a 'default' here so the compiler can spot incompatible enum changes. 95 } 96 LOG(ERROR) << "Unexpected thread state: " << internal_thread_state; 97 return -1; // Unreachable. 98 } 99 100 static jboolean Thread_nativeHoldsLock(JNIEnv* env, jobject java_thread, jobject java_object) { 101 ScopedObjectAccess soa(env); 102 mirror::Object* object = soa.Decode<mirror::Object*>(java_object); 103 if (object == nullptr) { 104 ThrowNullPointerException("object == null"); 105 return JNI_FALSE; 106 } 107 MutexLock mu(soa.Self(), *Locks::thread_list_lock_); 108 Thread* thread = Thread::FromManagedThread(soa, java_thread); 109 return thread->HoldsLock(object); 110 } 111 112 static void Thread_nativeInterrupt(JNIEnv* env, jobject java_thread) { 113 ScopedFastNativeObjectAccess soa(env); 114 MutexLock mu(soa.Self(), *Locks::thread_list_lock_); 115 Thread* thread = Thread::FromManagedThread(soa, java_thread); 116 if (thread != nullptr) { 117 thread->Interrupt(soa.Self()); 118 } 119 } 120 121 static void Thread_nativeSetName(JNIEnv* env, jobject peer, jstring java_name) { 122 ScopedUtfChars name(env, java_name); 123 { 124 ScopedObjectAccess soa(env); 125 if (soa.Decode<mirror::Object*>(peer) == soa.Self()->GetPeer()) { 126 soa.Self()->SetThreadName(name.c_str()); 127 return; 128 } 129 } 130 // Suspend thread to avoid it from killing itself while we set its name. We don't just hold the 131 // thread list lock to avoid this, as setting the thread name causes mutator to lock/unlock 132 // in the DDMS send code. 133 ThreadList* thread_list = Runtime::Current()->GetThreadList(); 134 bool timed_out; 135 // Take suspend thread lock to avoid races with threads trying to suspend this one. 136 Thread* thread = thread_list->SuspendThreadByPeer(peer, true, false, &timed_out); 137 if (thread != nullptr) { 138 { 139 ScopedObjectAccess soa(env); 140 thread->SetThreadName(name.c_str()); 141 } 142 thread_list->Resume(thread, false); 143 } else if (timed_out) { 144 LOG(ERROR) << "Trying to set thread name to '" << name.c_str() << "' failed as the thread " 145 "failed to suspend within a generous timeout."; 146 } 147 } 148 149 /* 150 * Alter the priority of the specified thread. "new_priority" will range 151 * from Thread.MIN_PRIORITY to Thread.MAX_PRIORITY (1-10), with "normal" 152 * threads at Thread.NORM_PRIORITY (5). 153 */ 154 static void Thread_nativeSetPriority(JNIEnv* env, jobject java_thread, jint new_priority) { 155 ScopedObjectAccess soa(env); 156 MutexLock mu(soa.Self(), *Locks::thread_list_lock_); 157 Thread* thread = Thread::FromManagedThread(soa, java_thread); 158 if (thread != nullptr) { 159 thread->SetNativePriority(new_priority); 160 } 161 } 162 163 static void Thread_sleep(JNIEnv* env, jclass, jobject java_lock, jlong ms, jint ns) { 164 ScopedFastNativeObjectAccess soa(env); 165 mirror::Object* lock = soa.Decode<mirror::Object*>(java_lock); 166 Monitor::Wait(Thread::Current(), lock, ms, ns, true, kSleeping); 167 } 168 169 /* 170 * Causes the thread to temporarily pause and allow other threads to execute. 171 * 172 * The exact behavior is poorly defined. Some discussion here: 173 * http://www.cs.umd.edu/~pugh/java/memoryModel/archive/0944.html 174 */ 175 static void Thread_yield(JNIEnv*, jobject) { 176 sched_yield(); 177 } 178 179 static JNINativeMethod gMethods[] = { 180 NATIVE_METHOD(Thread, currentThread, "!()Ljava/lang/Thread;"), 181 NATIVE_METHOD(Thread, interrupted, "!()Z"), 182 NATIVE_METHOD(Thread, isInterrupted, "!()Z"), 183 NATIVE_METHOD(Thread, nativeCreate, "(Ljava/lang/Thread;JZ)V"), 184 NATIVE_METHOD(Thread, nativeGetStatus, "(Z)I"), 185 NATIVE_METHOD(Thread, nativeHoldsLock, "(Ljava/lang/Object;)Z"), 186 NATIVE_METHOD(Thread, nativeInterrupt, "!()V"), 187 NATIVE_METHOD(Thread, nativeSetName, "(Ljava/lang/String;)V"), 188 NATIVE_METHOD(Thread, nativeSetPriority, "(I)V"), 189 NATIVE_METHOD(Thread, sleep, "!(Ljava/lang/Object;JI)V"), 190 NATIVE_METHOD(Thread, yield, "()V"), 191 }; 192 193 void register_java_lang_Thread(JNIEnv* env) { 194 REGISTER_NATIVE_METHODS("java/lang/Thread"); 195 } 196 197 } // namespace art 198
