# HG changeset patch
# User zgu
# Date 1342703750 14400
# Node ID 58a04a45a549a359c1830154017b59cf87f9898b
# Parent  d5bc62fcfac757695724b27e5c5ee4dc17d9d997# Parent  04a9b3789683264847f9f4cb7a20765c53c2b3bf
Merge

diff -r 04a9b3789683 -r 58a04a45a549 src/share/vm/services/memRecorder.cpp
--- a/src/share/vm/services/memRecorder.cpp	Mon Jul 16 14:05:34 2012 -0400
+++ b/src/share/vm/services/memRecorder.cpp	Thu Jul 19 09:15:50 2012 -0400
@@ -45,11 +45,11 @@
 }
 
 
-debug_only(volatile jint MemRecorder::_instance_count = 0;)
+volatile jint MemRecorder::_instance_count = 0;
 
 MemRecorder::MemRecorder() {
   assert(MemTracker::is_on(), "Native memory tracking is off");
-  debug_only(Atomic::inc(&_instance_count);)
+  Atomic::inc(&_instance_count);
   debug_only(set_generation();)
 
   if (MemTracker::track_callsite()) {
@@ -83,9 +83,7 @@
     delete _next;
   }
 
-#ifdef ASSERT
   Atomic::dec(&_instance_count);
-#endif
 }
 
 // Sorting order:
diff -r 04a9b3789683 -r 58a04a45a549 src/share/vm/services/memRecorder.hpp
--- a/src/share/vm/services/memRecorder.hpp	Mon Jul 16 14:05:34 2012 -0400
+++ b/src/share/vm/services/memRecorder.hpp	Thu Jul 19 09:15:50 2012 -0400
@@ -249,9 +249,9 @@
 
   SequencedRecordIterator pointer_itr();
 
- public:
+ protected:
   // number of MemRecorder instance
-  debug_only(static volatile jint _instance_count;)
+  static volatile jint _instance_count;
 
  private:
   // sorting function, sort records into following order
diff -r 04a9b3789683 -r 58a04a45a549 src/share/vm/services/memSnapshot.cpp
--- a/src/share/vm/services/memSnapshot.cpp	Mon Jul 16 14:05:34 2012 -0400
+++ b/src/share/vm/services/memSnapshot.cpp	Thu Jul 19 09:15:50 2012 -0400
@@ -173,7 +173,7 @@
     _staging_area = new (std::nothrow)MemPointerArrayImpl<SeqMemPointerRecord>();
   }
 
-  _lock = new (std::nothrow) Mutex(Monitor::native, "memSnapshotLock");
+  _lock = new (std::nothrow) Mutex(Monitor::max_nonleaf - 1, "memSnapshotLock");
   NOT_PRODUCT(_untracked_count = 0;)
 }
 
diff -r 04a9b3789683 -r 58a04a45a549 src/share/vm/services/memTrackWorker.hpp
--- a/src/share/vm/services/memTrackWorker.hpp	Mon Jul 16 14:05:34 2012 -0400
+++ b/src/share/vm/services/memTrackWorker.hpp	Thu Jul 19 09:15:50 2012 -0400
@@ -67,7 +67,7 @@
   NOT_PRODUCT(int _last_gen_in_use;)
 
   inline int generations_in_use() const {
-    return (_tail <= _head ? (_head - _tail + 1) : (MAX_GENERATIONS - (_tail - _head) + 1));
+    return (_tail >= _head ? (_tail - _head + 1) : (MAX_GENERATIONS - (_head - _tail) + 1));
   }
 };
 
diff -r 04a9b3789683 -r 58a04a45a549 src/share/vm/services/memTracker.cpp
--- a/src/share/vm/services/memTracker.cpp	Mon Jul 16 14:05:34 2012 -0400
+++ b/src/share/vm/services/memTracker.cpp	Thu Jul 19 09:15:50 2012 -0400
@@ -54,7 +54,7 @@
 MemRecorder*                    MemTracker::_global_recorder = NULL;
 MemSnapshot*                    MemTracker::_snapshot = NULL;
 MemBaseline                     MemTracker::_baseline;
-Mutex                           MemTracker::_query_lock(Monitor::native, "NMT_queryLock");
+Mutex*                          MemTracker::_query_lock = NULL;
 volatile MemRecorder*           MemTracker::_merge_pending_queue = NULL;
 volatile MemRecorder*           MemTracker::_pooled_recorders = NULL;
 MemTrackWorker*                 MemTracker::_worker_thread = NULL;
@@ -89,6 +89,12 @@
       return;
     }
 
+    _query_lock = new (std::nothrow) Mutex(Monitor::max_nonleaf, "NMT_queryLock");
+    if (_query_lock == NULL) {
+      shutdown(NMT_out_of_memory);
+      return;
+    }
+
     debug_only(_main_thread_tid = os::current_thread_id();)
     _state = NMT_bootstrapping_single_thread;
     NMT_track_callsite = (_tracking_level == NMT_detail && can_walk_stack());
@@ -164,7 +170,7 @@
   {
     // shared baseline and snapshot are the only objects needed to
     // create query results
-    MutexLockerEx locker(&_query_lock, true);
+    MutexLockerEx locker(_query_lock, true);
     // cleanup baseline data and snapshot
     _baseline.clear();
     delete _snapshot;
@@ -351,15 +357,17 @@
     }
 
     if (thread != NULL) {
-      // for a JavaThread, if it is running in native state, we need to transition it to
-      // VM state, so it can stop at safepoint. JavaThread running in VM state does not
-      // need lock to write records.
       if (thread->is_Java_thread() && ((JavaThread*)thread)->is_safepoint_visible()) {
-        if (((JavaThread*)thread)->thread_state() == _thread_in_native) {
-          ThreadInVMfromNative trans((JavaThread*)thread);
-          create_record_in_recorder(addr, flags, size, pc, thread);
+        JavaThread*      java_thread = static_cast<JavaThread*>(thread);
+        JavaThreadState  state = java_thread->thread_state();
+        if (SafepointSynchronize::safepoint_safe(java_thread, state)) {
+          // JavaThreads that are safepoint safe, can run through safepoint,
+          // so ThreadCritical is needed to ensure no threads at safepoint create
+          // new records while the records are being gathered and the sequence number is changing
+          ThreadCritical tc;
+          create_record_in_recorder(addr, flags, size, pc, java_thread);
         } else {
-          create_record_in_recorder(addr, flags, size, pc, thread);
+          create_record_in_recorder(addr, flags, size, pc, java_thread);
         }
       } else {
         // other threads, such as worker and watcher threads, etc. need to
@@ -384,10 +392,9 @@
 // write a record to proper recorder. No lock can be taken from this method
 // down.
 void MemTracker::create_record_in_recorder(address addr, MEMFLAGS flags,
-    size_t size, address pc, Thread* thread) {
-    assert(thread == NULL || thread->is_Java_thread(), "wrong thread");
+    size_t size, address pc, JavaThread* thread) {
 
-    MemRecorder* rc = get_thread_recorder((JavaThread*)thread);
+    MemRecorder* rc = get_thread_recorder(thread);
     if (rc != NULL) {
       rc->record(addr, flags, size, pc);
     }
@@ -454,17 +461,18 @@
       }
     }
     _sync_point_skip_count = 0;
-    // walk all JavaThreads to collect recorders
-    SyncThreadRecorderClosure stc;
-    Threads::threads_do(&stc);
-
-    _thread_count = stc.get_thread_count();
-    MemRecorder* pending_recorders = get_pending_recorders();
-
     {
       // This method is running at safepoint, with ThreadCritical lock,
       // it should guarantee that NMT is fully sync-ed.
       ThreadCritical tc;
+
+      // walk all JavaThreads to collect recorders
+      SyncThreadRecorderClosure stc;
+      Threads::threads_do(&stc);
+
+      _thread_count = stc.get_thread_count();
+      MemRecorder* pending_recorders = get_pending_recorders();
+
       if (_global_recorder != NULL) {
         _global_recorder->set_next(pending_recorders);
         pending_recorders = _global_recorder;
@@ -480,8 +488,6 @@
 
   // now, it is the time to shut whole things off
   if (_state == NMT_final_shutdown) {
-    _tracking_level = NMT_off;
-
     // walk all JavaThreads to delete all recorders
     SyncThreadRecorderClosure stc;
     Threads::threads_do(&stc);
@@ -493,8 +499,16 @@
         _global_recorder = NULL;
       }
     }
-
-    _state = NMT_shutdown;
+    MemRecorder* pending_recorders = get_pending_recorders();
+    if (pending_recorders != NULL) {
+      delete pending_recorders;
+    }
+    // try at a later sync point to ensure MemRecorder instance drops to zero to
+    // completely shutdown NMT
+    if (MemRecorder::_instance_count == 0) {
+      _state = NMT_shutdown;
+      _tracking_level = NMT_off;
+    }
   }
 }
 
@@ -528,7 +542,7 @@
 
 // baseline current memory snapshot
 bool MemTracker::baseline() {
-  MutexLockerEx lock(&_query_lock, true);
+  MutexLockerEx lock(_query_lock, true);
   MemSnapshot* snapshot = get_snapshot();
   if (snapshot != NULL) {
     return _baseline.baseline(*snapshot, false);
@@ -539,7 +553,7 @@
 // print memory usage from current snapshot
 bool MemTracker::print_memory_usage(BaselineOutputer& out, size_t unit, bool summary_only) {
   MemBaseline  baseline;
-  MutexLockerEx lock(&_query_lock, true);
+  MutexLockerEx lock(_query_lock, true);
   MemSnapshot* snapshot = get_snapshot();
   if (snapshot != NULL && baseline.baseline(*snapshot, summary_only)) {
     BaselineReporter reporter(out, unit);
@@ -551,7 +565,7 @@
 
 // compare memory usage between current snapshot and baseline
 bool MemTracker::compare_memory_usage(BaselineOutputer& out, size_t unit, bool summary_only) {
-  MutexLockerEx lock(&_query_lock, true);
+  MutexLockerEx lock(_query_lock, true);
   if (_baseline.baselined()) {
     MemBaseline baseline;
     MemSnapshot* snapshot = get_snapshot();
diff -r 04a9b3789683 -r 58a04a45a549 src/share/vm/services/memTracker.hpp
--- a/src/share/vm/services/memTracker.hpp	Mon Jul 16 14:05:34 2012 -0400
+++ b/src/share/vm/services/memTracker.hpp	Thu Jul 19 09:15:50 2012 -0400
@@ -126,6 +126,8 @@
         return "Native memory tracking has been shutdown by user";
       case NMT_normal:
         return "Native memory tracking has been shutdown due to process exiting";
+      case NMT_out_of_memory:
+        return "Native memory tracking has been shutdown due to out of native memory";
       case NMT_initialization:
         return "Native memory tracking failed to initialize";
       case NMT_error_reporting:
@@ -326,7 +328,7 @@
   static void create_memory_record(address addr, MEMFLAGS type,
                    size_t size, address pc, Thread* thread);
   static void create_record_in_recorder(address addr, MEMFLAGS type,
-                   size_t size, address pc, Thread* thread);
+                   size_t size, address pc, JavaThread* thread);
 
  private:
   // global memory snapshot
@@ -336,7 +338,7 @@
   static MemBaseline      _baseline;
 
   // query lock
-  static Mutex            _query_lock;
+  static Mutex*           _query_lock;
 
   // a thread can start to allocate memory before it is attached
   // to VM 'Thread', those memory activities are recorded here.