ART: Add Agent Thread API
Add support for RunAgentThread. Add test.
Bug: 31684593
Test: m test-art-host-run-test-931-agent-thread
Change-Id: I5deb213fb06eedc5ee78a340458cf0dff615d0ac
diff --git a/runtime/openjdkjvmti/ti_thread.cc b/runtime/openjdkjvmti/ti_thread.cc
index 2bcdd8c..970cc24 100644
--- a/runtime/openjdkjvmti/ti_thread.cc
+++ b/runtime/openjdkjvmti/ti_thread.cc
@@ -443,4 +443,80 @@
return ERR(NONE);
}
+struct AgentData {
+ const void* arg;
+ jvmtiStartFunction proc;
+ jthread thread;
+ JavaVM* java_vm;
+ jvmtiEnv* jvmti_env;
+ jint priority;
+};
+
+static void* AgentCallback(void* arg) {
+ std::unique_ptr<AgentData> data(reinterpret_cast<AgentData*>(arg));
+ CHECK(data->thread != nullptr);
+
+ // We already have a peer. So call our special Attach function.
+ art::Thread* self = art::Thread::Attach("JVMTI Agent thread", true, data->thread);
+ CHECK(self != nullptr);
+ // The name in Attach() is only for logging. Set the thread name. This is important so
+ // that the thread is no longer seen as starting up.
+ {
+ art::ScopedObjectAccess soa(self);
+ self->SetThreadName("JVMTI Agent thread");
+ }
+
+ // Release the peer.
+ JNIEnv* env = self->GetJniEnv();
+ env->DeleteGlobalRef(data->thread);
+ data->thread = nullptr;
+
+ // Run the agent code.
+ data->proc(data->jvmti_env, env, const_cast<void*>(data->arg));
+
+ // Detach the thread.
+ int detach_result = data->java_vm->DetachCurrentThread();
+ CHECK_EQ(detach_result, 0);
+
+ return nullptr;
+}
+
+jvmtiError ThreadUtil::RunAgentThread(jvmtiEnv* jvmti_env,
+ jthread thread,
+ jvmtiStartFunction proc,
+ const void* arg,
+ jint priority) {
+ if (priority < JVMTI_THREAD_MIN_PRIORITY || priority > JVMTI_THREAD_MAX_PRIORITY) {
+ return ERR(INVALID_PRIORITY);
+ }
+ JNIEnv* env = art::Thread::Current()->GetJniEnv();
+ if (thread == nullptr || !env->IsInstanceOf(thread, art::WellKnownClasses::java_lang_Thread)) {
+ return ERR(INVALID_THREAD);
+ }
+ if (proc == nullptr) {
+ return ERR(NULL_POINTER);
+ }
+
+ std::unique_ptr<AgentData> data(new AgentData);
+ data->arg = arg;
+ data->proc = proc;
+ // We need a global ref for Java objects, as local refs will be invalid.
+ data->thread = env->NewGlobalRef(thread);
+ data->java_vm = art::Runtime::Current()->GetJavaVM();
+ data->jvmti_env = jvmti_env;
+ data->priority = priority;
+
+ pthread_t pthread;
+ int pthread_create_result = pthread_create(&pthread,
+ nullptr,
+ &AgentCallback,
+ reinterpret_cast<void*>(data.get()));
+ if (pthread_create_result != 0) {
+ return ERR(INTERNAL);
+ }
+ data.release();
+
+ return ERR(NONE);
+}
+
} // namespace openjdkjvmti