1.1 --- a/src/share/vm/jfr/instrumentation/jfrJvmtiAgent.cpp Sun Jun 07 18:57:54 2020 +0100
1.2 +++ b/src/share/vm/jfr/instrumentation/jfrJvmtiAgent.cpp Fri Jun 12 02:59:56 2020 +0100
1.3 @@ -1,5 +1,5 @@
1.4 /*
1.5 - * Copyright (c) 2016, 2018, Oracle and/or its affiliates. All rights reserved.
1.6 + * Copyright (c) 2016, 2019, Oracle and/or its affiliates. All rights reserved.
1.7 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
1.8 *
1.9 * This code is free software; you can redistribute it and/or modify it
1.10 @@ -31,7 +31,9 @@
1.11 #include "jfr/recorder/service/jfrOptionSet.hpp"
1.12 #include "jfr/support/jfrEventClass.hpp"
1.13 #include "memory/resourceArea.hpp"
1.14 +#include "prims/jvmtiEnvBase.hpp"
1.15 #include "prims/jvmtiExport.hpp"
1.16 +#include "prims/jvmtiUtil.hpp"
1.17 #include "runtime/interfaceSupport.hpp"
1.18 #include "runtime/thread.inline.hpp"
1.19 #include "utilities/exceptions.hpp"
1.20 @@ -51,19 +53,17 @@
1.21 }
1.22 }
1.23
1.24 -static jvmtiError set_event_notification_mode(jvmtiEventMode mode,
1.25 - jvmtiEvent event,
1.26 - jthread event_thread,
1.27 - ...) {
1.28 - if (jfr_jvmti_env == NULL) {
1.29 - return JVMTI_ERROR_NONE;
1.30 - }
1.31 +static bool set_event_notification_mode(jvmtiEventMode mode,
1.32 + jvmtiEvent event,
1.33 + jthread event_thread,
1.34 + ...) {
1.35 + assert(jfr_jvmti_env != NULL, "invariant");
1.36 const jvmtiError jvmti_ret_code = jfr_jvmti_env->SetEventNotificationMode(mode, event, event_thread);
1.37 check_jvmti_error(jfr_jvmti_env, jvmti_ret_code, "SetEventNotificationMode");
1.38 - return jvmti_ret_code;
1.39 + return jvmti_ret_code == JVMTI_ERROR_NONE;
1.40 }
1.41
1.42 -static jvmtiError update_class_file_load_hook_event(jvmtiEventMode mode) {
1.43 +static bool update_class_file_load_hook_event(jvmtiEventMode mode) {
1.44 return set_event_notification_mode(mode, JVMTI_EVENT_CLASS_FILE_LOAD_HOOK, NULL);
1.45 }
1.46
1.47 @@ -116,12 +116,23 @@
1.48 return classes;
1.49 }
1.50
1.51 -static void log_and_throw(TRAPS) {
1.52 +// caller needs ResourceMark
1.53 +static void log_and_throw(jvmtiError error, TRAPS) {
1.54 if (!HAS_PENDING_EXCEPTION) {
1.55 DEBUG_ONLY(JfrJavaSupport::check_java_thread_in_native(THREAD));
1.56 ThreadInVMfromNative tvmfn((JavaThread*)THREAD);
1.57 - if (true) tty->print_cr("JfrJvmtiAgent::retransformClasses failed");
1.58 - JfrJavaSupport::throw_class_format_error("JfrJvmtiAgent::retransformClasses failed", THREAD);
1.59 + const char base_error_msg[] = "JfrJvmtiAgent::retransformClasses failed: ";
1.60 + size_t length = sizeof base_error_msg; // includes terminating null
1.61 + const char* const jvmti_error_name = JvmtiUtil::error_name(error);
1.62 + assert(jvmti_error_name != NULL, "invariant");
1.63 + length += strlen(jvmti_error_name);
1.64 + char* error_msg = NEW_RESOURCE_ARRAY(char, length);
1.65 + jio_snprintf(error_msg, length, "%s%s", base_error_msg, jvmti_error_name);
1.66 + if (JVMTI_ERROR_INVALID_CLASS_FORMAT == error) {
1.67 + JfrJavaSupport::throw_class_format_error(error_msg, THREAD);
1.68 + } else {
1.69 + JfrJavaSupport::throw_runtime_exception(error_msg, THREAD);
1.70 + }
1.71 }
1.72 }
1.73
1.74 @@ -136,12 +147,15 @@
1.75 }
1.76 }
1.77
1.78 +static bool is_valid_jvmti_phase() {
1.79 + return JvmtiEnvBase::get_phase() == JVMTI_PHASE_LIVE;
1.80 +}
1.81 +
1.82 void JfrJvmtiAgent::retransform_classes(JNIEnv* env, jobjectArray classes_array, TRAPS) {
1.83 assert(env != NULL, "invariant");
1.84 + assert(classes_array != NULL, "invariant");
1.85 + assert(is_valid_jvmti_phase(), "invariant");
1.86 DEBUG_ONLY(JfrJavaSupport::check_java_thread_in_native(THREAD));
1.87 - if (classes_array == NULL) {
1.88 - return;
1.89 - }
1.90 const jint classes_count = env->GetArrayLength(classes_array);
1.91 if (classes_count <= 0) {
1.92 return;
1.93 @@ -152,27 +166,27 @@
1.94 for (jint i = 0; i < classes_count; i++) {
1.95 jclass clz = (jclass)env->GetObjectArrayElement(classes_array, i);
1.96 check_exception_and_log(env, THREAD);
1.97 -
1.98 + classes[i] = clz;
1.99 + }
1.100 + {
1.101 // inspecting the oop/klass requires a thread transition
1.102 - {
1.103 - ThreadInVMfromNative transition((JavaThread*)THREAD);
1.104 - if (JdkJfrEvent::is_a(clz)) {
1.105 - // should have been tagged already
1.106 - assert(JdkJfrEvent::is_subklass(clz), "invariant");
1.107 - } else {
1.108 + ThreadInVMfromNative transition((JavaThread*)THREAD);
1.109 + for (jint i = 0; i < classes_count; ++i) {
1.110 + jclass clz = classes[i];
1.111 + if (!JdkJfrEvent::is_a(clz)) {
1.112 // outside the event hierarchy
1.113 JdkJfrEvent::tag_as_host(clz);
1.114 }
1.115 }
1.116 -
1.117 - classes[i] = clz;
1.118 }
1.119 - if (jfr_jvmti_env->RetransformClasses(classes_count, classes) != JVMTI_ERROR_NONE) {
1.120 - log_and_throw(THREAD);
1.121 + DEBUG_ONLY(JfrJavaSupport::check_java_thread_in_native(THREAD));
1.122 + const jvmtiError result = jfr_jvmti_env->RetransformClasses(classes_count, classes);
1.123 + if (result != JVMTI_ERROR_NONE) {
1.124 + log_and_throw(result, THREAD);
1.125 }
1.126 }
1.127
1.128 -static jvmtiError register_callbacks(JavaThread* jt) {
1.129 +static bool register_callbacks(JavaThread* jt) {
1.130 assert(jfr_jvmti_env != NULL, "invariant");
1.131 DEBUG_ONLY(JfrJavaSupport::check_java_thread_in_native(jt));
1.132 jvmtiEventCallbacks callbacks;
1.133 @@ -181,10 +195,10 @@
1.134 callbacks.ClassFileLoadHook = jfr_on_class_file_load_hook;
1.135 const jvmtiError jvmti_ret_code = jfr_jvmti_env->SetEventCallbacks(&callbacks, sizeof(callbacks));
1.136 check_jvmti_error(jfr_jvmti_env, jvmti_ret_code, "SetEventCallbacks");
1.137 - return jvmti_ret_code;
1.138 + return jvmti_ret_code == JVMTI_ERROR_NONE;
1.139 }
1.140
1.141 -static jvmtiError register_capabilities(JavaThread* jt) {
1.142 +static bool register_capabilities(JavaThread* jt) {
1.143 assert(jfr_jvmti_env != NULL, "invariant");
1.144 DEBUG_ONLY(JfrJavaSupport::check_java_thread_in_native(jt));
1.145 jvmtiCapabilities capabilities;
1.146 @@ -194,7 +208,7 @@
1.147 capabilities.can_retransform_any_class = 1;
1.148 const jvmtiError jvmti_ret_code = jfr_jvmti_env->AddCapabilities(&capabilities);
1.149 check_jvmti_error(jfr_jvmti_env, jvmti_ret_code, "Add Capabilities");
1.150 - return jvmti_ret_code;
1.151 + return jvmti_ret_code == JVMTI_ERROR_NONE;
1.152 }
1.153
1.154 static jint create_jvmti_env(JavaThread* jt) {
1.155 @@ -205,16 +219,14 @@
1.156 return vm->GetEnv((void **)&jfr_jvmti_env, JVMTI_VERSION);
1.157 }
1.158
1.159 -static jvmtiError unregister_callbacks(JavaThread* jt) {
1.160 - if (jfr_jvmti_env == NULL) {
1.161 - return JVMTI_ERROR_NONE;
1.162 - }
1.163 +static bool unregister_callbacks(JavaThread* jt) {
1.164 + assert(jfr_jvmti_env != NULL, "invariant");
1.165 jvmtiEventCallbacks callbacks;
1.166 /* Set empty callbacks */
1.167 memset(&callbacks, 0, sizeof(callbacks));
1.168 const jvmtiError jvmti_ret_code = jfr_jvmti_env->SetEventCallbacks(&callbacks, sizeof(callbacks));
1.169 check_jvmti_error(jfr_jvmti_env, jvmti_ret_code, "SetEventCallbacks");
1.170 - return jvmti_ret_code;
1.171 + return jvmti_ret_code == JVMTI_ERROR_NONE;
1.172 }
1.173
1.174 JfrJvmtiAgent::JfrJvmtiAgent() {}
1.175 @@ -222,20 +234,17 @@
1.176 JfrJvmtiAgent::~JfrJvmtiAgent() {
1.177 JavaThread* jt = current_java_thread();
1.178 DEBUG_ONLY(JfrJavaSupport::check_java_thread_in_vm(jt));
1.179 - ThreadToNativeFromVM transition(jt);
1.180 - update_class_file_load_hook_event(JVMTI_DISABLE);
1.181 - unregister_callbacks(jt);
1.182 if (jfr_jvmti_env != NULL) {
1.183 + ThreadToNativeFromVM transition(jt);
1.184 + update_class_file_load_hook_event(JVMTI_DISABLE);
1.185 + unregister_callbacks(jt);
1.186 jfr_jvmti_env->DisposeEnvironment();
1.187 jfr_jvmti_env = NULL;
1.188 }
1.189 - agent = NULL;
1.190 }
1.191
1.192 -static bool initialize() {
1.193 - JavaThread* const jt = current_java_thread();
1.194 +static bool initialize(JavaThread* jt) {
1.195 assert(jt != NULL, "invariant");
1.196 - assert(jt->thread_state() == _thread_in_vm, "invariant");
1.197 DEBUG_ONLY(JfrJavaSupport::check_java_thread_in_vm(jt));
1.198 ThreadToNativeFromVM transition(jt);
1.199 if (create_jvmti_env(jt) != JNI_OK) {
1.200 @@ -243,25 +252,38 @@
1.201 return false;
1.202 }
1.203 assert(jfr_jvmti_env != NULL, "invariant");
1.204 - if (register_capabilities(jt) != JVMTI_ERROR_NONE) {
1.205 + if (!register_capabilities(jt)) {
1.206 return false;
1.207 }
1.208 - if (register_callbacks(jt) != JVMTI_ERROR_NONE) {
1.209 + if (!register_callbacks(jt)) {
1.210 return false;
1.211 }
1.212 - if (update_class_file_load_hook_event(JVMTI_ENABLE) != JVMTI_ERROR_NONE) {
1.213 - return false;
1.214 + return update_class_file_load_hook_event(JVMTI_ENABLE);
1.215 +}
1.216 +
1.217 +static void log_and_throw_illegal_state_exception(TRAPS) {
1.218 + DEBUG_ONLY(JfrJavaSupport::check_java_thread_in_vm(THREAD));
1.219 + const char* const illegal_state_msg = "An attempt was made to start JFR too early in the VM initialization sequence.";
1.220 + if (true) {
1.221 + tty->print_cr("%s\n", illegal_state_msg);
1.222 + tty->print_cr("JFR uses JVMTI RetransformClasses and requires the JVMTI state to have entered JVMTI_PHASE_LIVE.\n");
1.223 + tty->print_cr("Please initialize JFR in response to event JVMTI_EVENT_VM_INIT instead of JVMTI_EVENT_VM_START.\n");
1.224 }
1.225 - return true;
1.226 + JfrJavaSupport::throw_illegal_state_exception(illegal_state_msg, THREAD);
1.227 }
1.228
1.229 bool JfrJvmtiAgent::create() {
1.230 - assert(jfr_jvmti_env == NULL, "invariant");
1.231 + assert(agent == NULL, "invariant");
1.232 + JavaThread* const jt = current_java_thread();
1.233 + if (!is_valid_jvmti_phase()) {
1.234 + log_and_throw_illegal_state_exception(jt);
1.235 + return false;
1.236 + }
1.237 agent = new JfrJvmtiAgent();
1.238 if (agent == NULL) {
1.239 return false;
1.240 }
1.241 - if (!initialize()) {
1.242 + if (!initialize(jt)) {
1.243 delete agent;
1.244 agent = NULL;
1.245 return false;
1.246 @@ -275,4 +297,3 @@
1.247 agent = NULL;
1.248 }
1.249 }
1.250 -
