--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/hotspot/src/share/vm/runtime/synchronizer.hpp Sat Dec 01 00:00:00 2007 +0000
@@ -0,0 +1,216 @@
+/*
+ * Copyright 1998-2007 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.
+ *
+ */
+
+class BasicLock VALUE_OBJ_CLASS_SPEC {
+ friend class VMStructs;
+ private:
+ volatile markOop _displaced_header;
+ public:
+ markOop displaced_header() const { return _displaced_header; }
+ void set_displaced_header(markOop header) { _displaced_header = header; }
+
+ void print_on(outputStream* st) const;
+
+ // move a basic lock (used during deoptimization
+ void move_to(oop obj, BasicLock* dest);
+
+ static int displaced_header_offset_in_bytes() { return offset_of(BasicLock, _displaced_header); }
+};
+
+// A BasicObjectLock associates a specific Java object with a BasicLock.
+// It is currently embedded in an interpreter frame.
+
+// Because some machines have alignment restrictions on the control stack,
+// the actual space allocated by the interpreter may include padding words
+// after the end of the BasicObjectLock. Also, in order to guarantee
+// alignment of the embedded BasicLock objects on such machines, we
+// put the embedded BasicLock at the beginning of the struct.
+
+class BasicObjectLock VALUE_OBJ_CLASS_SPEC {
+ friend class VMStructs;
+ private:
+ BasicLock _lock; // the lock, must be double word aligned
+ oop _obj; // object holds the lock;
+
+ public:
+ // Manipulation
+ oop obj() const { return _obj; }
+ void set_obj(oop obj) { _obj = obj; }
+ BasicLock* lock() { return &_lock; }
+
+ // Note: Use frame::interpreter_frame_monitor_size() for the size of BasicObjectLocks
+ // in interpreter activation frames since it includes machine-specific padding.
+ static int size() { return sizeof(BasicObjectLock)/wordSize; }
+
+ // GC support
+ void oops_do(OopClosure* f) { f->do_oop(&_obj); }
+
+ static int obj_offset_in_bytes() { return offset_of(BasicObjectLock, _obj); }
+ static int lock_offset_in_bytes() { return offset_of(BasicObjectLock, _lock); }
+};
+
+class ObjectMonitor;
+
+class ObjectSynchronizer : AllStatic {
+ friend class VMStructs;
+ public:
+ typedef enum {
+ owner_self,
+ owner_none,
+ owner_other
+ } LockOwnership;
+ // exit must be implemented non-blocking, since the compiler cannot easily handle
+ // deoptimization at monitor exit. Hence, it does not take a Handle argument.
+
+ // This is full version of monitor enter and exit. I choose not
+ // to use enter() and exit() in order to make sure user be ware
+ // of the performance and semantics difference. They are normally
+ // used by ObjectLocker etc. The interpreter and compiler use
+ // assembly copies of these routines. Please keep them synchornized.
+ //
+ // attempt_rebias flag is used by UseBiasedLocking implementation
+ static void fast_enter (Handle obj, BasicLock* lock, bool attempt_rebias, TRAPS);
+ static void fast_exit (oop obj, BasicLock* lock, Thread* THREAD);
+
+ // WARNING: They are ONLY used to handle the slow cases. They should
+ // only be used when the fast cases failed. Use of these functions
+ // without previous fast case check may cause fatal error.
+ static void slow_enter (Handle obj, BasicLock* lock, TRAPS);
+ static void slow_exit (oop obj, BasicLock* lock, Thread* THREAD);
+
+ // Used only to handle jni locks or other unmatched monitor enter/exit
+ // Internally they will use heavy weight monitor.
+ static void jni_enter (Handle obj, TRAPS);
+ static bool jni_try_enter(Handle obj, Thread* THREAD); // Implements Unsafe.tryMonitorEnter
+ static void jni_exit (oop obj, Thread* THREAD);
+
+ // Handle all interpreter, compiler and jni cases
+ static void wait (Handle obj, jlong millis, TRAPS);
+ static void notify (Handle obj, TRAPS);
+ static void notifyall (Handle obj, TRAPS);
+
+ // Special internal-use-only method for use by JVM infrastructure
+ // that needs to wait() on a java-level object but that can't risk
+ // throwing unexpected InterruptedExecutionExceptions.
+ static void waitUninterruptibly (Handle obj, jlong Millis, Thread * THREAD) ;
+
+ // used by classloading to free classloader object lock,
+ // wait on an internal lock, and reclaim original lock
+ // with original recursion count
+ static intptr_t complete_exit (Handle obj, TRAPS);
+ static void reenter (Handle obj, intptr_t recursion, TRAPS);
+
+ // thread-specific and global objectMonitor free list accessors
+ static ObjectMonitor * omAlloc (Thread * Self) ;
+ static void omRelease (Thread * Self, ObjectMonitor * m) ;
+ static void omFlush (Thread * Self) ;
+
+ // Inflate light weight monitor to heavy weight monitor
+ static ObjectMonitor* inflate(Thread * Self, oop obj);
+ // This version is only for internal use
+ static ObjectMonitor* inflate_helper(oop obj);
+
+ // Returns the identity hash value for an oop
+ // NOTE: It may cause monitor inflation
+ static intptr_t identity_hash_value_for(Handle obj);
+ static intptr_t FastHashCode (Thread * Self, oop obj) ;
+
+ // java.lang.Thread support
+ static bool current_thread_holds_lock(JavaThread* thread, Handle h_obj);
+ static LockOwnership query_lock_ownership(JavaThread * self, Handle h_obj);
+
+ static JavaThread* get_lock_owner(Handle h_obj, bool doLock);
+
+ // JNI detach support
+ static void release_monitors_owned_by_thread(TRAPS);
+ static void monitors_iterate(MonitorClosure* m);
+
+ // GC: we current use aggressive monitor deflation policy
+ // Basically we deflate all monitors that are not busy.
+ // An adaptive profile-based deflation policy could be used if needed
+ static void deflate_idle_monitors();
+ static void oops_do(OopClosure* f);
+
+ // debugging
+ static void trace_locking(Handle obj, bool is_compiled, bool is_method, bool is_locking) PRODUCT_RETURN;
+ static void verify() PRODUCT_RETURN;
+ static int verify_objmon_isinpool(ObjectMonitor *addr) PRODUCT_RETURN0;
+
+ private:
+ enum { _BLOCKSIZE = 128 };
+ static ObjectMonitor* gBlockList;
+ static ObjectMonitor * volatile gFreeList;
+
+ public:
+ static void Initialize () ;
+ static PerfCounter * _sync_ContendedLockAttempts ;
+ static PerfCounter * _sync_FutileWakeups ;
+ static PerfCounter * _sync_Parks ;
+ static PerfCounter * _sync_EmptyNotifications ;
+ static PerfCounter * _sync_Notifications ;
+ static PerfCounter * _sync_SlowEnter ;
+ static PerfCounter * _sync_SlowExit ;
+ static PerfCounter * _sync_SlowNotify ;
+ static PerfCounter * _sync_SlowNotifyAll ;
+ static PerfCounter * _sync_FailedSpins ;
+ static PerfCounter * _sync_SuccessfulSpins ;
+ static PerfCounter * _sync_PrivateA ;
+ static PerfCounter * _sync_PrivateB ;
+ static PerfCounter * _sync_MonInCirculation ;
+ static PerfCounter * _sync_MonScavenged ;
+ static PerfCounter * _sync_Inflations ;
+ static PerfCounter * _sync_Deflations ;
+ static PerfLongVariable * _sync_MonExtant ;
+
+ public:
+ static void RegisterSpinCallback (int (*)(intptr_t, int), intptr_t) ;
+
+};
+
+// ObjectLocker enforced balanced locking and can never thrown an
+// IllegalMonitorStateException. However, a pending exception may
+// have to pass through, and we must also be able to deal with
+// asynchronous exceptions. The caller is responsible for checking
+// the threads pending exception if needed.
+// doLock was added to support classloading with UnsyncloadClass which
+// requires flag based choice of locking the classloader lock.
+class ObjectLocker : public StackObj {
+ private:
+ Thread* _thread;
+ Handle _obj;
+ BasicLock _lock;
+ bool _dolock; // default true
+ public:
+ ObjectLocker(Handle obj, Thread* thread, bool doLock = true);
+ ~ObjectLocker();
+
+ // Monitor behavior
+ void wait (TRAPS) { ObjectSynchronizer::wait (_obj, 0, CHECK); } // wait forever
+ void notify_all(TRAPS) { ObjectSynchronizer::notifyall(_obj, CHECK); }
+ void waitUninterruptibly (TRAPS) { ObjectSynchronizer::waitUninterruptibly (_obj, 0, CHECK);}
+ // complete_exit gives up lock completely, returning recursion count
+ // reenter reclaims lock with original recursion count
+ intptr_t complete_exit(TRAPS) { return ObjectSynchronizer::complete_exit(_obj, CHECK_0); }
+ void reenter(intptr_t recursion, TRAPS) { ObjectSynchronizer::reenter(_obj, recursion, CHECK); }
+};