hotspot/src/share/vm/runtime/handles.cpp
changeset 1 489c9b5090e2
child 5547 f4b087cbb361
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/hotspot/src/share/vm/runtime/handles.cpp	Sat Dec 01 00:00:00 2007 +0000
@@ -0,0 +1,185 @@
+/*
+ * Copyright 1997-2003 Sun Microsystems, Inc.  All Rights Reserved.
+ * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
+ *
+ * This code is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 only, as
+ * published by the Free Software Foundation.
+ *
+ * This code is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
+ * version 2 for more details (a copy is included in the LICENSE file that
+ * accompanied this code).
+ *
+ * You should have received a copy of the GNU General Public License version
+ * 2 along with this work; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
+ * CA 95054 USA or visit www.sun.com if you need additional information or
+ * have any questions.
+ *
+ */
+
+# include "incls/_precompiled.incl"
+# include "incls/_handles.cpp.incl"
+
+#ifdef ASSERT
+oop* HandleArea::allocate_handle(oop obj) {
+  assert(_handle_mark_nesting > 1, "memory leak: allocating handle outside HandleMark");
+  assert(_no_handle_mark_nesting == 0, "allocating handle inside NoHandleMark");
+  assert(SharedSkipVerify || obj->is_oop(), "sanity check");
+  return real_allocate_handle(obj);
+}
+
+Handle::Handle(Thread* thread, oop obj) {
+  assert(thread == Thread::current(), "sanity check");
+  if (obj == NULL) {
+    _handle = NULL;
+  } else {
+    _handle = thread->handle_area()->allocate_handle(obj);
+  }
+}
+
+#endif
+
+static uintx chunk_oops_do(OopClosure* f, Chunk* chunk, char* chunk_top) {
+  oop* bottom = (oop*) chunk->bottom();
+  oop* top    = (oop*) chunk_top;
+  uintx handles_visited = top - bottom;
+  assert(top >= bottom && top <= (oop*) chunk->top(), "just checking");
+  // during GC phase 3, a handle may be a forward pointer that
+  // is not yet valid, so loosen the assertion
+  while (bottom < top) {
+//    assert((*bottom)->is_oop(), "handle should point to oop");
+      assert(Universe::heap()->is_in(*bottom), "handle should be valid heap address");
+    f->do_oop(bottom++);
+  }
+  return handles_visited;
+}
+
+// Used for debugging handle allocation.
+NOT_PRODUCT(jint _nof_handlemarks  = 0;)
+
+void HandleArea::oops_do(OopClosure* f) {
+  uintx handles_visited = 0;
+  // First handle the current chunk. It is filled to the high water mark.
+  handles_visited += chunk_oops_do(f, _chunk, _hwm);
+  // Then handle all previous chunks. They are completely filled.
+  Chunk* k = _first;
+  while(k != _chunk) {
+    handles_visited += chunk_oops_do(f, k, k->top());
+    k = k->next();
+  }
+
+  // The thread local handle areas should not get very large
+  if (TraceHandleAllocation && handles_visited > TotalHandleAllocationLimit) {
+#ifdef ASSERT
+    warning("%d: Visited in HandleMark : %d",
+      _nof_handlemarks, handles_visited);
+#else
+    warning("Visited in HandleMark : %d", handles_visited);
+#endif
+  }
+  if (_prev != NULL) _prev->oops_do(f);
+}
+
+void HandleMark::initialize(Thread* thread) {
+  _thread = thread;
+  // Save area
+  _area  = thread->handle_area();
+  // Save current top
+  _chunk = _area->_chunk;
+  _hwm   = _area->_hwm;
+  _max   = _area->_max;
+  NOT_PRODUCT(_size_in_bytes = _area->_size_in_bytes;)
+  debug_only(_area->_handle_mark_nesting++);
+  assert(_area->_handle_mark_nesting > 0, "must stack allocate HandleMarks");
+  debug_only(Atomic::inc(&_nof_handlemarks);)
+
+  // Link this in the thread
+  set_previous_handle_mark(thread->last_handle_mark());
+  thread->set_last_handle_mark(this);
+}
+
+
+HandleMark::~HandleMark() {
+  HandleArea* area = _area;   // help compilers with poor alias analysis
+  assert(area == _thread->handle_area(), "sanity check");
+  assert(area->_handle_mark_nesting > 0, "must stack allocate HandleMarks" );
+  debug_only(area->_handle_mark_nesting--);
+
+  // Debug code to trace the number of handles allocated per mark/
+#ifdef ASSERT
+  if (TraceHandleAllocation) {
+    size_t handles = 0;
+    Chunk *c = _chunk->next();
+    if (c == NULL) {
+      handles = area->_hwm - _hwm; // no new chunk allocated
+    } else {
+      handles = _max - _hwm;      // add rest in first chunk
+      while(c != NULL) {
+        handles += c->length();
+        c = c->next();
+      }
+      handles -= area->_max - area->_hwm; // adjust for last trunk not full
+    }
+    handles /= sizeof(void *); // Adjust for size of a handle
+    if (handles > HandleAllocationLimit) {
+      // Note: _nof_handlemarks is only set in debug mode
+      warning("%d: Allocated in HandleMark : %d", _nof_handlemarks, handles);
+    }
+  }
+#endif
+
+  // Delete later chunks
+  if( _chunk->next() ) {
+    _chunk->next_chop();
+  }
+  // Roll back arena to saved top markers
+  area->_chunk = _chunk;
+  area->_hwm = _hwm;
+  area->_max = _max;
+  NOT_PRODUCT(area->set_size_in_bytes(_size_in_bytes);)
+#ifdef ASSERT
+  // clear out first chunk (to detect allocation bugs)
+  if (ZapVMHandleArea) {
+    memset(_hwm, badHandleValue, _max - _hwm);
+  }
+  Atomic::dec(&_nof_handlemarks);
+#endif
+
+  // Unlink this from the thread
+  _thread->set_last_handle_mark(previous_handle_mark());
+}
+
+#ifdef ASSERT
+
+NoHandleMark::NoHandleMark() {
+  HandleArea* area = Thread::current()->handle_area();
+  area->_no_handle_mark_nesting++;
+  assert(area->_no_handle_mark_nesting > 0, "must stack allocate NoHandleMark" );
+}
+
+
+NoHandleMark::~NoHandleMark() {
+  HandleArea* area = Thread::current()->handle_area();
+  assert(area->_no_handle_mark_nesting > 0, "must stack allocate NoHandleMark" );
+  area->_no_handle_mark_nesting--;
+}
+
+
+ResetNoHandleMark::ResetNoHandleMark() {
+  HandleArea* area = Thread::current()->handle_area();
+  _no_handle_mark_nesting = area->_no_handle_mark_nesting;
+  area->_no_handle_mark_nesting = 0;
+}
+
+
+ResetNoHandleMark::~ResetNoHandleMark() {
+  HandleArea* area = Thread::current()->handle_area();
+  area->_no_handle_mark_nesting = _no_handle_mark_nesting;
+}
+
+#endif