jdk-sandbox: comparison src/hotspot/share/jfr/instrumentation/jfrJvmtiAgent.cpp

equal deleted inserted replaced

-:4c2557ab304e
+:127ca611f19b
 /*
-* Copyright (c) 2016, 2018, Oracle and/or its affiliates. All rights reserved.
+* Copyright (c) 2016, 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.
 #include "jfr/recorder/checkpoint/types/traceid/jfrTraceId.inline.hpp"
 #include "jfr/recorder/service/jfrOptionSet.hpp"
 #include "jfr/support/jfrEventClass.hpp"
 #include "logging/log.hpp"
 #include "memory/resourceArea.hpp"
+#include "prims/jvmtiEnvBase.hpp"
 #include "prims/jvmtiExport.hpp"
+#include "prims/jvmtiUtil.hpp"
 #include "runtime/interfaceSupport.inline.hpp"
 #include "runtime/thread.inline.hpp"
 #include "utilities/exceptions.hpp"
 static const size_t ERROR_MSG_BUFFER_SIZE = 256;
 NULL == errnum_str ? "Unknown" : errnum_str,
 NULL == str ? "" : str);
 }
 }
-static jvmtiError set_event_notification_mode(jvmtiEventMode mode,
+static bool set_event_notification_mode(jvmtiEventMode mode,
 jvmtiEvent event,
 jthread event_thread,
 ...) {
-if (jfr_jvmti_env == NULL) {
+assert(jfr_jvmti_env != NULL, "invariant");
-return JVMTI_ERROR_NONE;
-}
 const jvmtiError jvmti_ret_code = jfr_jvmti_env->SetEventNotificationMode(mode, event, event_thread);
 check_jvmti_error(jfr_jvmti_env, jvmti_ret_code, "SetEventNotificationMode");
-return jvmti_ret_code;
+return jvmti_ret_code == JVMTI_ERROR_NONE;
 }
-static jvmtiError update_class_file_load_hook_event(jvmtiEventMode mode) {
+static bool update_class_file_load_hook_event(jvmtiEventMode mode) {
 return set_event_notification_mode(mode, JVMTI_EVENT_CLASS_FILE_LOAD_HOOK, NULL);
 }
 static JavaThread* current_java_thread() {
 Thread* this_thread = Thread::current();
 JfrJavaSupport::throw_out_of_memory_error(error_buffer, CHECK_NULL);
 }
 return classes;
 }
-static void log_and_throw(TRAPS) {
+// caller needs ResourceMark
+static void log_and_throw(jvmtiError error, TRAPS) {
 if (!HAS_PENDING_EXCEPTION) {
 DEBUG_ONLY(JfrJavaSupport::check_java_thread_in_native(THREAD));
 ThreadInVMfromNative tvmfn((JavaThread*)THREAD);
-log_error(jfr, system)("JfrJvmtiAgent::retransformClasses failed");
+const char base_error_msg[] = "JfrJvmtiAgent::retransformClasses failed: ";
-JfrJavaSupport::throw_class_format_error("JfrJvmtiAgent::retransformClasses failed", THREAD);
+size_t length = sizeof base_error_msg; // includes terminating null
+const char* const jvmti_error_name = JvmtiUtil::error_name(error);
+assert(jvmti_error_name != NULL, "invariant");
+length += strlen(jvmti_error_name);
+char* error_msg = NEW_RESOURCE_ARRAY(char, length);
+jio_snprintf(error_msg, length, "%s%s", base_error_msg, jvmti_error_name);
+if (JVMTI_ERROR_INVALID_CLASS_FORMAT == error) {
+JfrJavaSupport::throw_class_format_error(error_msg, THREAD);
+} else {
+JfrJavaSupport::throw_runtime_exception(error_msg, THREAD);
+}
 }
 }
 static void check_exception_and_log(JNIEnv* env, TRAPS) {
 assert(env != NULL, "invariant");
 log_error(jfr, system)("GetObjectArrayElement threw an exception");
 return;
 }
 }
+static bool is_valid_jvmti_phase() {
+return JvmtiEnvBase::get_phase() == JVMTI_PHASE_LIVE;
+}
 void JfrJvmtiAgent::retransform_classes(JNIEnv* env, jobjectArray classes_array, TRAPS) {
 assert(env != NULL, "invariant");
+assert(classes_array != NULL, "invariant");
+assert(is_valid_jvmti_phase(), "invariant");
 DEBUG_ONLY(JfrJavaSupport::check_java_thread_in_native(THREAD));
-if (classes_array == NULL) {
-return;
-}
 const jint classes_count = env->GetArrayLength(classes_array);
 if (classes_count <= 0) {
 return;
 }
 ResourceMark rm(THREAD);
 jclass* const classes = create_classes_array(classes_count, CHECK);
 assert(classes != NULL, "invariant");
 for (jint i = 0; i < classes_count; i++) {
 jclass clz = (jclass)env->GetObjectArrayElement(classes_array, i);
 check_exception_and_log(env, THREAD);
+classes[i] = clz;
+}
+{
 // inspecting the oop/klass requires a thread transition
-{
+ThreadInVMfromNative transition((JavaThread*)THREAD);
-ThreadInVMfromNative transition((JavaThread*)THREAD);
+for (jint i = 0; i < classes_count; ++i) {
-if (JdkJfrEvent::is_a(clz)) {
+jclass clz = classes[i];
-// should have been tagged already
+if (!JdkJfrEvent::is_a(clz)) {
-assert(JdkJfrEvent::is_subklass(clz), "invariant");
-} else {
 // outside the event hierarchy
 JdkJfrEvent::tag_as_host(clz);
 }
 }
+}
-classes[i] = clz;
+DEBUG_ONLY(JfrJavaSupport::check_java_thread_in_native(THREAD));
-}
+const jvmtiError result = jfr_jvmti_env->RetransformClasses(classes_count, classes);
-if (jfr_jvmti_env->RetransformClasses(classes_count, classes) != JVMTI_ERROR_NONE) {
+if (result != JVMTI_ERROR_NONE) {
-log_and_throw(THREAD);
+log_and_throw(result, THREAD);
 }
 }
-static jvmtiError register_callbacks(JavaThread* jt) {
+static bool register_callbacks(JavaThread* jt) {
 assert(jfr_jvmti_env != NULL, "invariant");
 DEBUG_ONLY(JfrJavaSupport::check_java_thread_in_native(jt));
 jvmtiEventCallbacks callbacks;
 /* Set callbacks */
 memset(&callbacks, 0, sizeof(callbacks));
 callbacks.ClassFileLoadHook = jfr_on_class_file_load_hook;
 const jvmtiError jvmti_ret_code = jfr_jvmti_env->SetEventCallbacks(&callbacks, sizeof(callbacks));
 check_jvmti_error(jfr_jvmti_env, jvmti_ret_code, "SetEventCallbacks");
-return jvmti_ret_code;
+return jvmti_ret_code == JVMTI_ERROR_NONE;
 }
-static jvmtiError register_capabilities(JavaThread* jt) {
+static bool register_capabilities(JavaThread* jt) {
 assert(jfr_jvmti_env != NULL, "invariant");
 DEBUG_ONLY(JfrJavaSupport::check_java_thread_in_native(jt));
 jvmtiCapabilities capabilities;
 /* Add JVMTI capabilities */
 (void)memset(&capabilities, 0, sizeof(capabilities));
 capabilities.can_retransform_classes = 1;
 capabilities.can_retransform_any_class = 1;
 const jvmtiError jvmti_ret_code = jfr_jvmti_env->AddCapabilities(&capabilities);
 check_jvmti_error(jfr_jvmti_env, jvmti_ret_code, "Add Capabilities");
-return jvmti_ret_code;
+return jvmti_ret_code == JVMTI_ERROR_NONE;
 }
 static jint create_jvmti_env(JavaThread* jt) {
 assert(jfr_jvmti_env == NULL, "invariant");
 DEBUG_ONLY(JfrJavaSupport::check_java_thread_in_native(jt));
 extern struct JavaVM_ main_vm;
 JavaVM* vm = &main_vm;
 return vm->GetEnv((void **)&jfr_jvmti_env, JVMTI_VERSION);
 }
-static jvmtiError unregister_callbacks(JavaThread* jt) {
+static bool unregister_callbacks(JavaThread* jt) {
-if (jfr_jvmti_env == NULL) {
+assert(jfr_jvmti_env != NULL, "invariant");
-return JVMTI_ERROR_NONE;
-}
 jvmtiEventCallbacks callbacks;
 /* Set empty callbacks */
 memset(&callbacks, 0, sizeof(callbacks));
 const jvmtiError jvmti_ret_code = jfr_jvmti_env->SetEventCallbacks(&callbacks, sizeof(callbacks));
 check_jvmti_error(jfr_jvmti_env, jvmti_ret_code, "SetEventCallbacks");
-return jvmti_ret_code;
+return jvmti_ret_code == JVMTI_ERROR_NONE;
 }
 JfrJvmtiAgent::JfrJvmtiAgent() {}
 JfrJvmtiAgent::~JfrJvmtiAgent() {
 JavaThread* jt = current_java_thread();
 DEBUG_ONLY(JfrJavaSupport::check_java_thread_in_vm(jt));
-ThreadToNativeFromVM transition(jt);
-update_class_file_load_hook_event(JVMTI_DISABLE);
-unregister_callbacks(jt);
 if (jfr_jvmti_env != NULL) {
+ThreadToNativeFromVM transition(jt);
+update_class_file_load_hook_event(JVMTI_DISABLE);
+unregister_callbacks(jt);
 jfr_jvmti_env->DisposeEnvironment();
 jfr_jvmti_env = NULL;
 }
-agent = NULL;
+}
-}
+static bool initialize(JavaThread* jt) {
-static bool initialize() {
-JavaThread* const jt = current_java_thread();
 assert(jt != NULL, "invariant");
-assert(jt->thread_state() == _thread_in_vm, "invariant");
 DEBUG_ONLY(JfrJavaSupport::check_java_thread_in_vm(jt));
 ThreadToNativeFromVM transition(jt);
 if (create_jvmti_env(jt) != JNI_OK) {
 assert(jfr_jvmti_env == NULL, "invariant");
 return false;
 }
 assert(jfr_jvmti_env != NULL, "invariant");
-if (register_capabilities(jt) != JVMTI_ERROR_NONE) {
+if (!register_capabilities(jt)) {
 return false;
 }
-if (register_callbacks(jt) != JVMTI_ERROR_NONE) {
+if (!register_callbacks(jt)) {
 return false;
 }
-if (update_class_file_load_hook_event(JVMTI_ENABLE) != JVMTI_ERROR_NONE) {
+return update_class_file_load_hook_event(JVMTI_ENABLE);
-return false;
+}
-}
-return true;
+static void log_and_throw_illegal_state_exception(TRAPS) {
+DEBUG_ONLY(JfrJavaSupport::check_java_thread_in_vm(THREAD));
+const char* const illegal_state_msg = "An attempt was made to start JFR too early in the VM initialization sequence.";
+log_error(jfr, system)(illegal_state_msg);
+log_error(jfr, system)("JFR uses JVMTI RetransformClasses and requires the JVMTI state to have entered JVMTI_PHASE_LIVE.");
+log_error(jfr, system)("Please initialize JFR in response to event JVMTI_EVENT_VM_INIT instead of JVMTI_EVENT_VM_START.");
+JfrJavaSupport::throw_illegal_state_exception(illegal_state_msg, THREAD);
 }
 bool JfrJvmtiAgent::create() {
-assert(jfr_jvmti_env == NULL, "invariant");
+assert(agent == NULL, "invariant");
+JavaThread* const jt = current_java_thread();
+if (!is_valid_jvmti_phase()) {
+log_and_throw_illegal_state_exception(jt);
+return false;
+}
 agent = new JfrJvmtiAgent();
 if (agent == NULL) {
 return false;
 }
-if (!initialize()) {
+if (!initialize(jt)) {
 delete agent;
 agent = NULL;
 return false;
 }
 return true;
 if (agent != NULL) {
 delete agent;
 agent = NULL;
 }
 }

changeset 59259	127ca611f19b
parent 50113	caf115bb98ad