File
src/hotspot/share/prims/jvmtiImpl.cpp
has several methods which might be used to trace jvmti events.

JvmtiSuspendControl::print() fails with crash because it don't have resource mark.


diff -r 4364524f8cac src/hotspot/share/prims/jvmtiImpl.cpp
--- a/src/hotspot/share/prims/jvmtiImpl.cpp Fri Aug 30 09:38:40 2019 +0800
+++ b/src/hotspot/share/prims/jvmtiImpl.cpp Wed Sep 11 00:35:57 2019 +0000
@@ -881,6 +881,7 @@

 void JvmtiSuspendControl::print() {
 #ifndef PRODUCT
+ ResourceMark rm;
   LogStreamHandle(Trace, jvmti) log_stream;
   log_stream.print("Suspended Threads: [");
   for (JavaThreadIteratorWithHandle jtiwh; JavaThread *thread = jtiwh.next(); ) {

Complete method is

void JvmtiSuspendControl::print() {
#ifndef PRODUCT
  LogStreamHandle(Trace, jvmti) log_stream;
  log_stream.print("Suspended Threads: [");
  for (JavaThreadIteratorWithHandle jtiwh; JavaThread *thread = jtiwh.next(); ) {
#ifdef JVMTI_TRACE
    const char *name = JvmtiTrace::safe_get_thread_name(thread);
#else
    const char *name = "";
#endif /*JVMTI_TRACE */
    log_stream.print("%s(%c ", name, thread->is_being_ext_suspended() ? 'S' : '_');
    if (!thread->has_last_Java_frame()) {
      log_stream.print("no stack");
    }
    log_stream.print(") ");
  }
  log_stream.print_cr("]");
#endif
}