hotspot/src/share/vm/gc_implementation/shared/vmGCOperations.hpp
changeset 1 489c9b5090e2
child 386 7f121b1192f2
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/hotspot/src/share/vm/gc_implementation/shared/vmGCOperations.hpp	Sat Dec 01 00:00:00 2007 +0000
@@ -0,0 +1,168 @@
+/*
+ * Copyright 2005-2006 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.
+ *
+ */
+
+// The following class hierarchy represents
+// a set of operations (VM_Operation) related to GC.
+//
+//  VM_Operation
+//      VM_GC_Operation
+//          VM_GC_HeapInspection
+//          VM_GenCollectForAllocation
+//          VM_GenCollectFull
+//          VM_GenCollectFullConcurrent
+//          VM_ParallelGCFailedAllocation
+//          VM_ParallelGCFailedPermanentAllocation
+//          VM_ParallelGCSystemGC
+//  VM_GC_Operation
+//   - implements methods common to all classes in the hierarchy:
+//     prevents multiple gc requests and manages lock on heap;
+//
+//  VM_GC_HeapInspection
+//   - prints class histogram on SIGBREAK if PrintClassHistogram
+//     is specified; and also the attach "inspectheap" operation
+//
+//  VM_GenCollectForAllocation
+//  VM_ParallelGCFailedAllocation
+//  VM_ParallelGCFailedPermanentAllocation
+//   - this operation is invoked when allocation is failed;
+//     operation performs garbage collection and tries to
+//     allocate afterwards;
+//
+//  VM_GenCollectFull
+//  VM_GenCollectFullConcurrent
+//  VM_ParallelGCSystemGC
+//   - these operations preform full collection of heaps of
+//     different kind
+//
+
+class VM_GC_Operation: public VM_Operation {
+ protected:
+  BasicLock     _pending_list_basic_lock; // for refs pending list notification (PLL)
+  unsigned int  _gc_count_before;         // gc count before acquiring PLL
+  unsigned int  _full_gc_count_before;    // full gc count before acquiring PLL
+  bool          _full;                    // whether a "full" collection
+  bool          _prologue_succeeded;      // whether doit_prologue succeeded
+  GCCause::Cause _gc_cause;                // the putative cause for this gc op
+  bool          _gc_locked;               // will be set if gc was locked
+
+  virtual bool skip_operation() const;
+
+  // java.lang.ref.Reference support
+  void acquire_pending_list_lock();
+  void release_and_notify_pending_list_lock();
+
+ public:
+  VM_GC_Operation(unsigned int gc_count_before,
+                  unsigned int full_gc_count_before = 0,
+                  bool full = false) {
+    _full = full;
+    _prologue_succeeded = false;
+    _gc_count_before    = gc_count_before;
+
+    // A subclass constructor will likely overwrite the following
+    _gc_cause           = GCCause::_no_cause_specified;
+
+    _gc_locked = false;
+
+    if (full) {
+      _full_gc_count_before = full_gc_count_before;
+    }
+  }
+  ~VM_GC_Operation() {}
+
+  // Acquire the reference synchronization lock
+  virtual bool doit_prologue();
+  // Do notifyAll (if needed) and release held lock
+  virtual void doit_epilogue();
+
+  virtual bool allow_nested_vm_operations() const  { return true; }
+  bool prologue_succeeded() const { return _prologue_succeeded; }
+
+  void set_gc_locked() { _gc_locked = true; }
+  bool gc_locked() const  { return _gc_locked; }
+
+  static void notify_gc_begin(bool full = false);
+  static void notify_gc_end();
+};
+
+
+class VM_GC_HeapInspection: public VM_GC_Operation {
+ private:
+  outputStream* _out;
+  bool _full_gc;
+ public:
+  VM_GC_HeapInspection(outputStream* out, bool request_full_gc) :
+    VM_GC_Operation(0 /* total collections,      dummy, ignored */,
+                    0 /* total full collections, dummy, ignored */,
+                    request_full_gc) {
+    _out = out;
+    _full_gc = request_full_gc;
+  }
+
+  ~VM_GC_HeapInspection() {}
+  virtual VMOp_Type type() const { return VMOp_GC_HeapInspection; }
+  virtual bool skip_operation() const;
+  virtual bool doit_prologue();
+  virtual void doit();
+};
+
+
+class VM_GenCollectForAllocation: public VM_GC_Operation {
+ private:
+  HeapWord*   _res;
+  size_t      _size;                       // size of object to be allocated.
+  bool        _tlab;                       // alloc is of a tlab.
+ public:
+  VM_GenCollectForAllocation(size_t size,
+                             bool tlab,
+                             unsigned int gc_count_before)
+    : VM_GC_Operation(gc_count_before),
+      _size(size),
+      _tlab(tlab) {
+    _res = NULL;
+  }
+  ~VM_GenCollectForAllocation()  {}
+  virtual VMOp_Type type() const { return VMOp_GenCollectForAllocation; }
+  virtual void doit();
+  HeapWord* result() const       { return _res; }
+};
+
+
+// VM operation to invoke a collection of the heap as a
+// GenCollectedHeap heap.
+class VM_GenCollectFull: public VM_GC_Operation {
+ private:
+  int _max_level;
+ public:
+  VM_GenCollectFull(unsigned int gc_count_before,
+                    unsigned int full_gc_count_before,
+                    GCCause::Cause gc_cause,
+                      int max_level)
+    : VM_GC_Operation(gc_count_before, full_gc_count_before, true /* full */),
+      _max_level(max_level)
+  { _gc_cause = gc_cause; }
+  ~VM_GenCollectFull() {}
+  virtual VMOp_Type type() const { return VMOp_GenCollectFull; }
+  virtual void doit();
+};