jdk8-mips64-public/hotspot: src/share/vm/gc_implementation/shared/concurrentGCThread.hpp@b2ef234911c9 (annotated)

src/share/vm/gc_implementation/shared/concurrentGCThread.hpp@b2ef234911c9 (annotated)

src/share/vm/gc_implementation/shared/concurrentGCThread.hpp

Thu, 20 Sep 2012 09:52:56 -0700

author: johnc
date: Thu, 20 Sep 2012 09:52:56 -0700
changeset 4067: b2ef234911c9
parent 2964: 2a241e764894
child 4542: db9981fd3124
permissions: -rw-r--r--

7190666: G1: assert(_unused == 0) failed: Inconsistency in PLAB stats
Summary: Reset the fields in ParGCAllocBuffer, that are used for accumulating values for the ResizePLAB sensors in PLABStats, to zero after flushing the values to the PLABStats fields. Flush PLABStats values only when retiring the final allocation buffers prior to disposing of a G1ParScanThreadState object, rather than when retiring every allocation buffer.
Reviewed-by: jwilhelm, jmasa, ysr

 /*
  * Copyright (c) 2001, 2010, Oracle and/or its affiliates. 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 Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
  * or visit www.oracle.com if you need additional information or have any
  * questions.
  *
  */
 #ifndef SHARE_VM_GC_IMPLEMENTATION_SHARED_CONCURRENTGCTHREAD_HPP
 #define SHARE_VM_GC_IMPLEMENTATION_SHARED_CONCURRENTGCTHREAD_HPP
 #ifndef SERIALGC
 #include "runtime/thread.hpp"
 #endif
 class VoidClosure;
 // A SuspendibleThreadSet is (obviously) a set of threads that can be
 // suspended.  A thread can join and later leave the set, and periodically
 // yield.  If some thread (not in the set) requests, via suspend_all, that
 // the threads be suspended, then the requesting thread is blocked until
 // all the threads in the set have yielded or left the set.  (Threads may
 // not enter the set when an attempted suspension is in progress.)  The
 // suspending thread later calls resume_all, allowing the suspended threads
 // to continue.
 class SuspendibleThreadSet {
   Monitor* _m;
   int      _async;
   bool     _async_stop;
   int      _async_stopped;
   bool     _initialized;
   double   _suspend_all_start;
   void initialize_work();
  public:
   SuspendibleThreadSet() : _initialized(false) {}
   // Add the current thread to the set.  May block if a suspension
   // is in progress.
   void join();
   // Removes the current thread from the set.
   void leave();
   // Returns "true" iff an suspension is in progress.
   bool should_yield() { return _async_stop; }
   // Suspends the current thread if a suspension is in progress (for
   // the duration of the suspension.)
   void yield(const char* id);
   // Return when all threads in the set are suspended.
   void suspend_all();
   // Allow suspended threads to resume.
   void resume_all();
   // Redundant initializations okay.
   void initialize() {
     // Double-check dirty read idiom.
     if (!_initialized) initialize_work();
   }
 };
 class ConcurrentGCThread: public NamedThread {
   friend class VMStructs;
 protected:
   bool _should_terminate;
   bool _has_terminated;
   enum CGC_flag_type {
     CGC_nil           = 0x0,
     CGC_dont_suspend  = 0x1,
     CGC_CGC_safepoint = 0x2,
     CGC_VM_safepoint  = 0x4
   };
   static int _CGC_flag;
   static bool CGC_flag_is_set(int b)       { return (_CGC_flag & b) != 0; }
   static int set_CGC_flag(int b)           { return _CGC_flag |= b; }
   static int reset_CGC_flag(int b)         { return _CGC_flag &= ~b; }
   // All instances share this one set.
   static SuspendibleThreadSet _sts;
   // Create and start the thread (setting it's priority high.)
   void create_and_start();
   // Do initialization steps in the thread: record stack base and size,
   // init thread local storage, set JNI handle block.
   void initialize_in_thread();
   // Wait until Universe::is_fully_initialized();
   void wait_for_universe_init();
   // Record that the current thread is terminating, and will do more
   // concurrent work.
   void terminate();
 public:
   // Constructor
   ConcurrentGCThread();
   ~ConcurrentGCThread() {} // Exists to call NamedThread destructor.
   // Tester
   bool is_ConcurrentGC_thread() const          { return true;       }
   static void safepoint_synchronize();
   static void safepoint_desynchronize();
   // All overridings should probably do _sts::yield, but we allow
   // overriding for distinguished debugging messages.  Default is to do
   // nothing.
   virtual void yield() {}
   bool should_yield() { return _sts.should_yield(); }
   // they are prefixed by sts since there are already yield() and
   // should_yield() (non-static) methods in this class and it was an
   // easy way to differentiate them.
   static void stsYield(const char* id);
   static bool stsShouldYield();
   static void stsJoin();
   static void stsLeave();
 };
 // The SurrogateLockerThread is used by concurrent GC threads for
 // manipulating Java monitors, in particular, currently for
 // manipulating the pending_list_lock. XXX
 class SurrogateLockerThread: public JavaThread {
   friend class VMStructs;
  public:
   enum SLT_msg_type {
     empty = 0,           // no message
     acquirePLL,          // acquire pending list lock
     releaseAndNotifyPLL  // notify and release pending list lock
   };
  private:
   // the following are shared with the CMSThread
   SLT_msg_type  _buffer;  // communication buffer
   Monitor       _monitor; // monitor controlling buffer
   BasicLock     _basicLock; // used for PLL locking
  public:
   static SurrogateLockerThread* make(TRAPS);
   SurrogateLockerThread();
   bool is_hidden_from_external_view() const     { return true; }
   void loop(); // main method
   void manipulatePLL(SLT_msg_type msg);
 };
 #endif // SHARE_VM_GC_IMPLEMENTATION_SHARED_CONCURRENTGCTHREAD_HPP

Mercurial > jdk8-mips64-public > hotspot / annotate

src/share/vm/gc_implementation/shared/concurrentGCThread.hpp@b2ef234911c9 (annotated)

src/share/vm/gc_implementation/shared/concurrentGCThread.hpp