6361589: Print out stack trace for target thread of GC crash

Summary: If GC crashed with java thread involved, print out the java stack trace in error report
Reviewed-by: never, ysr, coleenp, dholmes

src/share/vm/runtime/frame.cpp

@@ -1190,9 +1190,19 @@ void frame::oops_entry_do(OopClosure* f, const RegisterMap* map) {
 
 
 void frame::oops_do_internal(OopClosure* f, CodeBlobClosure* cf, RegisterMap* map, bool use_interpreter_oop_map_cache) {
-         if (is_interpreted_frame())    { oops_interpreted_do(f, map, use_interpreter_oop_map_cache);
-  } else if (is_entry_frame())          { oops_entry_do      (f, map);
-  } else if (CodeCache::contains(pc())) { oops_code_blob_do  (f, cf, map);
+#ifndef PRODUCT
+  // simulate GC crash here to dump java thread in error report
+  if (CrashGCForDumpingJavaThread) {
+    char *t = NULL;
+    *t = 'c';
+  }
+#endif
+  if (is_interpreted_frame()) {
+    oops_interpreted_do(f, map, use_interpreter_oop_map_cache);
+  } else if (is_entry_frame()) {
+    oops_entry_do(f, map);
+  } else if (CodeCache::contains(pc())) {
+    oops_code_blob_do(f, cf, map);
   } else {
     ShouldNotReachHere();
   }

src/share/vm/runtime/globals.hpp

@@ -2554,6 +2554,9 @@ class CommandLineFlags {
           "Include miscellaneous runtime verifications in nmethod code; "   \
           "default off because it disturbs nmethod size heuristics")        \
                                                                             \
+  notproduct(bool, CrashGCForDumpingJavaThread, false,                      \
+          "Manually make GC thread crash then dump java stack trace;  "     \
+          "Test only")                                                      \
                                                                             \
   /* compilation */                                                         \
   product(bool, UseCompiler, true,                                          \

src/share/vm/runtime/thread.cpp

@@ -991,6 +991,7 @@ void JavaThread::allocate_threadObj(Handle thread_group, char* thread_name, bool
 // uniquely named instances should derive from this.
 NamedThread::NamedThread() : Thread() {
   _name = NULL;
+  _processed_thread = NULL;
 }
 
 NamedThread::~NamedThread() {
@@ -2333,6 +2334,27 @@ void JavaThread::gc_prologue() {
   frames_do(frame_gc_prologue);
 }
 
+// If the caller is a NamedThread, then remember, in the current scope,
+// the given JavaThread in its _processed_thread field.
+class RememberProcessedThread: public StackObj {
+  NamedThread* _cur_thr;
+public:
+  RememberProcessedThread(JavaThread* jthr) {
+    Thread* thread = Thread::current();
+    if (thread->is_Named_thread()) {
+      _cur_thr = (NamedThread *)thread;
+      _cur_thr->set_processed_thread(jthr);
+    } else {
+      _cur_thr = NULL;
+    }
+  }
+
+  ~RememberProcessedThread() {
+    if (_cur_thr) {
+      _cur_thr->set_processed_thread(NULL);
+    }
+  }
+};
 
 void JavaThread::oops_do(OopClosure* f, CodeBlobClosure* cf) {
   // Flush deferred store-barriers, if any, associated with
@@ -2349,6 +2371,8 @@ void JavaThread::oops_do(OopClosure* f, CodeBlobClosure* cf) {
           (has_last_Java_frame() && java_call_counter() > 0), "wrong java_sp info!");
 
   if (has_last_Java_frame()) {
+    // Record JavaThread to GC thread
+    RememberProcessedThread rpt(this);
 
     // Traverse the privileged stack
     if (_privileged_stack_top != NULL) {

src/share/vm/runtime/thread.hpp

@@ -48,7 +48,12 @@ class IdealGraphPrinter;
 
 // Class hierarchy
 // - Thread
-//   - VMThread
+//   - NamedThread
+//     - VMThread
+//     - ConcurrentGCThread
+//     - WorkerThread
+//       - GangWorker
+//       - GCTaskThread
 //   - JavaThread
 //   - WatcherThread
 
@@ -249,6 +254,7 @@ class Thread: public ThreadShadow {
   virtual bool is_GC_task_thread() const             { return false; }
   virtual bool is_Watcher_thread() const             { return false; }
   virtual bool is_ConcurrentGC_thread() const        { return false; }
+  virtual bool is_Named_thread() const               { return false; }
 
   virtual char* name() const { return (char*)"Unknown thread"; }
 
@@ -568,12 +574,18 @@ class NamedThread: public Thread {
   };
  private:
   char* _name;
+  // log JavaThread being processed by oops_do
+  JavaThread* _processed_thread;
+
  public:
   NamedThread();
   ~NamedThread();
   // May only be called once per thread.
   void set_name(const char* format, ...);
+  virtual bool is_Named_thread() const { return true; }
   virtual char* name() const { return _name == NULL ? (char*)"Unknown Thread" : _name; }
+  JavaThread *processed_thread() { return _processed_thread; }
+  void set_processed_thread(JavaThread *thread) { _processed_thread = thread; }
 };
 
 // Worker threads are named and have an id of an assigned work.

src/share/vm/runtime/vmStructs.cpp

@@ -666,6 +666,7 @@ static inline uint64_t cast_uint64_t(size_t x)
   nonstatic_field(Thread,                      _current_pending_monitor_is_from_java,         bool)                                  \
   nonstatic_field(Thread,                      _current_waiting_monitor,                      ObjectMonitor*)                        \
   nonstatic_field(NamedThread,                 _name,                                         char*)                                 \
+  nonstatic_field(NamedThread,                 _processed_thread,                             JavaThread*)                           \
   nonstatic_field(JavaThread,                  _next,                                         JavaThread*)                           \
   nonstatic_field(JavaThread,                  _threadObj,                                    oop)                                   \
   nonstatic_field(JavaThread,                  _anchor,                                       JavaFrameAnchor)                       \

src/share/vm/runtime/vmThread.cpp

@@ -204,8 +204,8 @@ void VMThread::create() {
 }
 
 
-VMThread::VMThread() : Thread() {
-  // nothing to do
+VMThread::VMThread() : NamedThread() {
+  set_name("VM Thread");
 }
 
 void VMThread::destroy() {

src/share/vm/runtime/vmThread.hpp

@@ -83,7 +83,7 @@ class VMOperationQueue : public CHeapObj {
 // like scavenge, garbage_collect etc.
 //
 
-class VMThread: public Thread {
+class VMThread: public NamedThread {
  private:
   static ThreadPriority _current_priority;
 
@@ -101,8 +101,6 @@ class VMThread: public Thread {
   bool is_VM_thread() const                      { return true; }
   bool is_GC_thread() const                      { return true; }
 
-  char* name() const { return (char*)"VM Thread"; }
-
   // The ever running loop for the VMThread
   void loop();
 

src/share/vm/utilities/vmError.cpp

@@ -502,6 +502,23 @@ void VMError::report(outputStream* st) {
 #endif // ZERO
      }
 
+  STEP(135, "(printing target Java thread stack)" )
+
+     // printing Java thread stack trace if it is involved in GC crash
+     if (_verbose && (_thread->is_Named_thread())) {
+       JavaThread*  jt = ((NamedThread *)_thread)->processed_thread();
+       if (jt != NULL) {
+         st->print_cr("JavaThread " PTR_FORMAT " (nid = " UINTX_FORMAT ") was being processed", jt, jt->osthread()->thread_id());
+         if (jt->has_last_Java_frame()) {
+           st->print_cr("Java frames: (J=compiled Java code, j=interpreted, Vv=VM code)");
+           for(StackFrameStream sfs(jt); !sfs.is_done(); sfs.next()) {
+             sfs.current()->print_on_error(st, buf, sizeof(buf), true);
+             st->cr();
+           }
+         }
+       }
+     }
+
   STEP(140, "(printing VM operation)" )
 
      if (_verbose && _thread && _thread->is_VM_thread()) {