8357650: ThreadSnapshot to take snapshot of thread for thread dumps

Co-authored-by: Alan Bateman <[email protected]>
Co-authored-by: Alex Menkov <[email protected]>
Reviewed-by: sspitsyn, kevinw

Author: Alex Menkov

src/hotspot/share/classfile/javaClasses.cpp

@@ -1872,7 +1872,7 @@ ByteSize java_lang_Thread::thread_id_offset() {
 }
 
 oop java_lang_Thread::park_blocker(oop java_thread) {
-  return java_thread->obj_field(_park_blocker_offset);
+  return java_thread->obj_field_access<MO_RELAXED>(_park_blocker_offset);
 }
 
 oop java_lang_Thread::async_get_stack_trace(oop java_thread, TRAPS) {

src/hotspot/share/classfile/vmSymbols.hpp

@@ -742,6 +742,12 @@ class SerializeClosure;
   template(jdk_internal_vm_ThreadDumper,           "jdk/internal/vm/ThreadDumper")                                \
   template(dumpThreads_name,                       "dumpThreads")                                                 \
   template(dumpThreadsToJson_name,                 "dumpThreadsToJson")                                           \
+  template(jdk_internal_vm_ThreadSnapshot,         "jdk/internal/vm/ThreadSnapshot")                              \
+  template(jdk_internal_vm_ThreadLock,             "jdk/internal/vm/ThreadSnapshot$ThreadLock")                   \
+  template(jdk_internal_vm_ThreadLock_signature,   "Ljdk/internal/vm/ThreadSnapshot$ThreadLock;")                 \
+  template(jdk_internal_vm_ThreadLock_array,       "[Ljdk/internal/vm/ThreadSnapshot$ThreadLock;")                \
+  template(java_lang_StackTraceElement_of_name,    "of")                                                          \
+  template(java_lang_StackTraceElement_of_signature, "([Ljava/lang/StackTraceElement;)[Ljava/lang/StackTraceElement;") \
                                                                                                                   \
   /* jcmd Thread.vthread_scheduler and Thread.vthread_pollers */                                                  \
   template(jdk_internal_vm_JcmdVThreadCommands,    "jdk/internal/vm/JcmdVThreadCommands")                         \

src/hotspot/share/include/jvm.h

@@ -301,6 +301,9 @@ JVM_HoldsLock(JNIEnv *env, jclass threadClass, jobject obj);
 JNIEXPORT jobject JNICALL
 JVM_GetStackTrace(JNIEnv *env, jobject thread);
 
+JNIEXPORT jobject JNICALL
+JVM_CreateThreadSnapshot(JNIEnv* env, jobject thread);
+
 JNIEXPORT jobjectArray JNICALL
 JVM_GetAllThreads(JNIEnv *env, jclass dummy);
 

src/hotspot/share/prims/jvm.cpp

@@ -2961,6 +2961,15 @@ JVM_ENTRY(jobject, JVM_GetStackTrace(JNIEnv *env, jobject jthread))
   return JNIHandles::make_local(THREAD, trace);
 JVM_END
 
+JVM_ENTRY(jobject, JVM_CreateThreadSnapshot(JNIEnv* env, jobject jthread))
+#if INCLUDE_JVMTI
+  oop snapshot = ThreadSnapshotFactory::get_thread_snapshot(jthread, THREAD);
+  return JNIHandles::make_local(THREAD, snapshot);
+#else
+  return nullptr;
+#endif
+JVM_END
+
 JVM_ENTRY(void, JVM_SetNativeThreadName(JNIEnv* env, jobject jthread, jstring name))
   // We don't use a ThreadsListHandle here because the current thread
   // must be alive.

src/hotspot/share/prims/jvmtiThreadState.hpp

@@ -77,7 +77,7 @@ class JvmtiEnvThreadStateIterator : public StackObj {
 //
 // Virtual Thread Mount State Transition (VTMS transition) mechanism
 //
-class JvmtiVTMSTransitionDisabler {
+class JvmtiVTMSTransitionDisabler : public AnyObj {
  private:
   static volatile int _VTMS_transition_disable_for_one_count; // transitions for one virtual thread are disabled while it is positive
   static volatile int _VTMS_transition_disable_for_all_count; // transitions for all virtual threads are disabled while it is positive

src/hotspot/share/services/diagnosticCommand.cpp

@@ -127,7 +127,9 @@ void DCmd::register_dcmds(){
   DCmdFactory::register_DCmdFactory(new DCmdFactoryImpl<JVMTIDataDumpDCmd>(full_export, true, false));
 #endif // INCLUDE_JVMTI
   DCmdFactory::register_DCmdFactory(new DCmdFactoryImpl<ThreadDumpDCmd>(full_export, true, false));
+#if INCLUDE_JVMTI
   DCmdFactory::register_DCmdFactory(new DCmdFactoryImpl<ThreadDumpToFileDCmd>(full_export, true, false));
+#endif // INCLUDE_JVMTI
   DCmdFactory::register_DCmdFactory(new DCmdFactoryImpl<VThreadSchedulerDCmd>(full_export, true, false));
   DCmdFactory::register_DCmdFactory(new DCmdFactoryImpl<VThreadPollersDCmd>(full_export, true, false));
   DCmdFactory::register_DCmdFactory(new DCmdFactoryImpl<ClassLoaderStatsDCmd>(full_export, true, false));