8336401: Remove the option onjcmd from the jdwp agent

Reviewed-by: cjplummer, mbaesken

src/hotspot/share/services/diagnosticCommand.cpp

@@ -52,7 +52,6 @@
 #include "runtime/fieldDescriptor.inline.hpp"
 #include "runtime/flags/jvmFlag.hpp"
 #include "runtime/handles.inline.hpp"
-#include "runtime/interfaceSupport.inline.hpp"
 #include "runtime/javaCalls.hpp"
 #include "runtime/jniHandles.hpp"
 #include "runtime/os.hpp"
@@ -160,11 +159,6 @@ void DCmd::register_dcmds(){
  DCmdFactory::register_DCmdFactory(new DCmdFactoryImpl<JMXStopRemoteDCmd>(jmx_agent_export_flags, true,false));
  DCmdFactory::register_DCmdFactory(new DCmdFactoryImpl<JMXStatusDCmd>(jmx_agent_export_flags, true,false));
 
- // Debug on cmd (only makes sense with JVMTI since the agentlib needs it).
-#if INCLUDE_JVMTI
- DCmdFactory::register_DCmdFactory(new DCmdFactoryImpl<DebugOnCmdStartDCmd>(full_export, true, true));
-#endif // INCLUDE_JVMTI
-
 #if INCLUDE_CDS
  DCmdFactory::register_DCmdFactory(new DCmdFactoryImpl<DumpSharedArchiveDCmd>(full_export, true, false));
 #endif // INCLUDE_CDS
@@ -1058,45 +1052,6 @@ void DumpSharedArchiveDCmd::execute(DCmdSource source, TRAPS) {
 }
 #endif // INCLUDE_CDS
 
-#if INCLUDE_JVMTI
-extern "C" typedef char const* (JNICALL *debugInit_startDebuggingViaCommandPtr)(JNIEnv* env, jthread thread, char const** transport_name,
- char const** address, jboolean* first_start);
-static debugInit_startDebuggingViaCommandPtr dvc_start_ptr = nullptr;
-
-void DebugOnCmdStartDCmd::execute(DCmdSource source, TRAPS) {
- char const* transport = nullptr;
- char const* addr = nullptr;
- jboolean is_first_start = JNI_FALSE;
- JavaThread* thread = THREAD;
- jthread jt = JNIHandles::make_local(thread->threadObj());
- ThreadToNativeFromVM ttn(thread);
- const char *error = "Could not find jdwp agent.";
-
- if (!dvc_start_ptr) {
- JvmtiAgentList::Iterator it = JvmtiAgentList::agents();
- while (it.has_next()) {
- JvmtiAgent* agent = it.next();
- if ((strcmp("jdwp", agent->name()) == 0) && (dvc_start_ptr == nullptr)) {
- char const* func = "debugInit_startDebuggingViaCommand";
- dvc_start_ptr = (debugInit_startDebuggingViaCommandPtr) os::find_agent_function(agent, false, &func, 1);
- }
- }
- }
-
- if (dvc_start_ptr) {
- error = dvc_start_ptr(thread->jni_environment(), jt, &transport, &addr, &is_first_start);
- }
-
- if (error != nullptr) {
- output()->print_cr("Debugging has not been started: %s", error);
- } else {
- output()->print_cr(is_first_start ? "Debugging has been started." : "Debugging is already active.");
- output()->print_cr("Transport : %s", transport ? transport : "#unknown");
- output()->print_cr("Address : %s", addr ? addr : "#unknown");
- }
-}
-#endif // INCLUDE_JVMTI
-
 ThreadDumpToFileDCmd::ThreadDumpToFileDCmd(outputStream* output, bool heap) :
  DCmdWithParser(output, heap),
  _overwrite("-overwrite", "May overwrite existing file", "BOOLEAN", false, "false"),

src/hotspot/share/services/diagnosticCommand.hpp

@@ -886,27 +886,6 @@ class ClassesDCmd : public DCmdWithParser {
  virtual void execute(DCmdSource source, TRAPS);
 };
 
-#if INCLUDE_JVMTI
-class DebugOnCmdStartDCmd : public DCmd {
-public:
- DebugOnCmdStartDCmd(outputStream* output, bool heap) : DCmd(output, heap) {}
- static const char* name() {
- return "VM.start_java_debugging";
- }
- static const char* description() {
- return "Starts up the Java debugging if the jdwp agentlib was enabled with the option onjcmd=y.";
- }
- static const char* impact() {
- return "High: Switches the VM into Java debug mode.";
- }
- static const JavaPermission permission() {
- JavaPermission p = { "java.lang.management.ManagementPermission", "control", nullptr };
- return p;
- }
- virtual void execute(DCmdSource source, TRAPS);
-};
-#endif // INCLUDE_JVMTI
-
 class EventLogDCmd : public DCmdWithParser {
 protected:
  DCmdArgument<char*> _log;

src/jdk.jdwp.agent/share/native/libjdwp/debugInit.c

@@ -81,9 +81,6 @@ static unsigned logflags = 0; /* Log flags */
 
 static char *names; /* strings derived from OnLoad options */
 
-static jboolean allowStartViaJcmd = JNI_FALSE; /* if true we allow the debugging to be started via a jcmd */
-static jboolean startedViaJcmd = JNI_FALSE; /* if false, we have not yet started debugging via a jcmd */
-
 /*
  * Elements of the transports bag
  */
@@ -983,7 +980,6 @@ parseOptions(char *options)
  int length;
  char *str;
  char *errmsg;
- jboolean onJcmd = JNI_FALSE;
 
  /* Set defaults */
  gdata->assertOn = DEFAULT_ASSERT_ON;
@@ -1231,10 +1227,6 @@ parseOptions(char *options)
  if ( !get_boolean(&str, &useStandardAlloc) ) {
  goto syntax_error;
  }
- } else if (strcmp(buf, "onjcmd") == 0) {
- if (!get_boolean(&str, &onJcmd)) {
- goto syntax_error;
- }
  } else {
  goto syntax_error;
  }
@@ -1285,20 +1277,6 @@ parseOptions(char *options)
  }
  }
 
- if (onJcmd) {
- if (launchOnInit != NULL) {
- errmsg = "Cannot combine onjcmd and launch suboptions";
- goto bad_option_with_errmsg;
- }
- if (!isServer) {
- errmsg = "Can only use onjcmd with server=y";
- goto bad_option_with_errmsg;
- }
- suspendOnInit = JNI_FALSE;
- initOnStartup = JNI_FALSE;
- allowStartViaJcmd = JNI_TRUE;
- }
-
  return JNI_TRUE;
 
 syntax_error:
@@ -1367,45 +1345,3 @@ debugInit_exit(jvmtiError error, const char *msg)
  // Last chance to die, this kills the entire process.
  forceExit(EXIT_JVMTI_ERROR);
 }
-
-static jboolean getFirstTransport(void *item, void *arg)
-{
- TransportSpec** store = arg;
- *store = item;
-
- return JNI_FALSE; /* Want the first */
-}
-
-/* Call to start up debugging. */
-JNIEXPORT char const* JNICALL debugInit_startDebuggingViaCommand(JNIEnv* env, jthread thread, char const** transport_name,
- char const** address, jboolean* first_start) {
- jboolean is_first_start = JNI_FALSE;
- TransportSpec* spec = NULL;
-
- if (!vmInitialized) {
- return "Not yet initialized. Try again later.";
- }
-
- if (!allowStartViaJcmd) {
- return "Starting debugging via jcmd was not enabled via the onjcmd option of the jdwp agent.";
- }
-
- if (!startedViaJcmd) {
- startedViaJcmd = JNI_TRUE;
- is_first_start = JNI_TRUE;
- initialize(env, thread, EI_VM_INIT, NULL);
- }
-
- bagEnumerateOver(transports, getFirstTransport, &spec);
-
- if ((spec != NULL) && (transport_name != NULL) && (address != NULL)) {
- *transport_name = spec->name;
- *address = spec->address;
- }
-
- if (first_start != NULL) {
- *first_start = is_first_start;
- }
-
- return NULL;
-}

test/jdk/jdk/jfr/event/runtime/TestAgentEvent.java

@@ -65,7 +65,7 @@
  * jdk.jfr.event.runtime.TestAgentEvent
  * testJavaDynamic
  *
- * @run main/othervm -XX:+UnlockExperimentalVMOptions -XX:-UseFastUnorderedTimeStamps -agentlib:jdwp=transport=dt_socket,server=y,address=any,onjcmd=y
+ * @run main/othervm -XX:+UnlockExperimentalVMOptions -XX:-UseFastUnorderedTimeStamps -agentlib:jdwp=transport=dt_socket,server=y,suspend=n,address=0
  * jdk.jfr.event.runtime.TestAgentEvent
  * testNativeStatic
  */
@@ -122,7 +122,7 @@ private static void testNativeStatic() throws Throwable {
  RecordedEvent e = events.get(1);
  System.out.println(e);
  Events.assertField(e, "name").equal("jdwp");
- Events.assertField(e, "options").equal("transport=dt_socket,server=y,address=any,onjcmd=y");
+ Events.assertField(e, "options").equal("transport=dt_socket,server=y,suspend=n,address=0");
  Events.assertField(e, "dynamic").equal(false);
  Instant initializationTime = e.getInstant("initializationTime");
  if (initializationTime.isAfter(interval.getStartTime())) {