hotspot/src/share/vm/runtime/mutexLocker.hpp
changeset 1 489c9b5090e2
child 228 69939fa91efd
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/hotspot/src/share/vm/runtime/mutexLocker.hpp	Sat Dec 01 00:00:00 2007 +0000
@@ -0,0 +1,325 @@
+/*
+ * Copyright 1997-2007 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.
+ *
+ */
+
+// Mutexes used in the VM.
+
+extern Mutex*   Patching_lock;                   // a lock used to guard code patching of compiled code
+extern Monitor* SystemDictionary_lock;           // a lock on the system dictonary
+extern Mutex*   PackageTable_lock;               // a lock on the class loader package table
+extern Mutex*   CompiledIC_lock;                 // a lock used to guard compiled IC patching and access
+extern Mutex*   InlineCacheBuffer_lock;          // a lock used to guard the InlineCacheBuffer
+extern Mutex*   VMStatistic_lock;                // a lock used to guard statistics count increment
+extern Mutex*   JNIGlobalHandle_lock;            // a lock on creating JNI global handles
+extern Mutex*   JNIHandleBlockFreeList_lock;     // a lock on the JNI handle block free list
+extern Mutex*   JNICachedItableIndex_lock;       // a lock on caching an itable index during JNI invoke
+extern Mutex*   JmethodIdCreation_lock;          // a lock on creating JNI method identifiers
+extern Mutex*   JfieldIdCreation_lock;           // a lock on creating JNI static field identifiers
+extern Monitor* JNICritical_lock;                // a lock used while entering and exiting JNI critical regions, allows GC to sometimes get in
+extern Mutex*   JvmtiThreadState_lock;           // a lock on modification of JVMTI thread data
+extern Monitor* JvmtiPendingEvent_lock;          // a lock on the JVMTI pending events list
+extern Mutex*   Heap_lock;                       // a lock on the heap
+extern Mutex*   ExpandHeap_lock;                 // a lock on expanding the heap
+extern Mutex*   AdapterHandlerLibrary_lock;      // a lock on the AdapterHandlerLibrary
+extern Mutex*   SignatureHandlerLibrary_lock;    // a lock on the SignatureHandlerLibrary
+extern Mutex*   VtableStubs_lock;                // a lock on the VtableStubs
+extern Mutex*   SymbolTable_lock;                // a lock on the symbol table
+extern Mutex*   StringTable_lock;                // a lock on the interned string table
+extern Mutex*   CodeCache_lock;                  // a lock on the CodeCache, rank is special, use MutexLockerEx
+extern Mutex*   MethodData_lock;                 // a lock on installation of method data
+extern Mutex*   RetData_lock;                    // a lock on installation of RetData inside method data
+extern Mutex*   DerivedPointerTableGC_lock;      // a lock to protect the derived pointer table
+extern Monitor* VMOperationQueue_lock;           // a lock on queue of vm_operations waiting to execute
+extern Monitor* VMOperationRequest_lock;         // a lock on Threads waiting for a vm_operation to terminate
+extern Monitor* Safepoint_lock;                  // a lock used by the safepoint abstraction
+extern Monitor* SerializePage_lock;              // a lock used when VMThread changing serialize memory page permission during safepoint
+extern Monitor* Threads_lock;                    // a lock on the Threads table of active Java threads
+                                                 // (also used by Safepoints too to block threads creation/destruction)
+extern Monitor* CGC_lock;                        // used for coordination between
+                                                 // fore- & background GC threads.
+extern Mutex*   STS_init_lock;                   // coordinate initialization of SuspendibleThreadSets.
+extern Monitor* SLT_lock;                        // used in CMS GC for acquiring PLL
+extern Monitor* iCMS_lock;                       // CMS incremental mode start/stop notification
+extern Monitor* FullGCCount_lock;                // in support of "concurrent" full gc
+                                                 // (see option ExplicitGCInvokesConcurrent)
+extern Mutex*   ParGCRareEvent_lock;             // Synchronizes various (rare) parallel GC ops.
+extern Mutex*   Compile_lock;                    // a lock held when Compilation is updating code (used to block CodeCache traversal, CHA updates, etc)
+extern Monitor* MethodCompileQueue_lock;         // a lock held when method compilations are enqueued, dequeued
+#ifdef TIERED
+extern Monitor* C1_lock;                         // a lock to ensure on single c1 compile is ever active
+#endif // TIERED
+extern Monitor* CompileThread_lock;              // a lock held by compile threads during compilation system initialization
+extern Mutex*   CompileTaskAlloc_lock;           // a lock held when CompileTasks are allocated
+extern Mutex*   CompileStatistics_lock;          // a lock held when updating compilation statistics
+extern Mutex*   MultiArray_lock;                 // a lock used to guard allocation of multi-dim arrays
+extern Monitor* Terminator_lock;                 // a lock used to guard termination of the vm
+extern Monitor* BeforeExit_lock;                 // a lock used to guard cleanups and shutdown hooks
+extern Monitor* Notify_lock;                     // a lock used to synchronize the start-up of the vm
+extern Monitor* Interrupt_lock;                  // a lock used for condition variable mediated interrupt processing
+extern Monitor* ProfileVM_lock;                  // a lock used for profiling the VMThread
+extern Mutex*   ProfilePrint_lock;               // a lock used to serialize the printing of profiles
+extern Mutex*   ExceptionCache_lock;             // a lock used to synchronize exception cache updates
+extern Mutex*   OsrList_lock;                    // a lock used to serialize access to OSR queues
+
+#ifndef PRODUCT
+extern Mutex*   FullGCALot_lock;                 // a lock to make FullGCALot MT safe
+#endif
+extern Mutex*   Debug1_lock;                     // A bunch of pre-allocated locks that can be used for tracing
+extern Mutex*   Debug2_lock;                     // down synchronization related bugs!
+extern Mutex*   Debug3_lock;
+
+extern Mutex*   RawMonitor_lock;
+extern Mutex*   PerfDataMemAlloc_lock;           // a lock on the allocator for PerfData memory for performance data
+extern Mutex*   PerfDataManager_lock;            // a long on access to PerfDataManager resources
+extern Mutex*   ParkerFreeList_lock;
+extern Mutex*   OopMapCacheAlloc_lock;           // protects allocation of oop_map caches
+
+extern Mutex*   Management_lock;                 // a lock used to serialize JVM management
+extern Monitor* LowMemory_lock;                  // a lock used for low memory detection
+
+// A MutexLocker provides mutual exclusion with respect to a given mutex
+// for the scope which contains the locker.  The lock is an OS lock, not
+// an object lock, and the two do not interoperate.  Do not use Mutex-based
+// locks to lock on Java objects, because they will not be respected if a
+// that object is locked using the Java locking mechanism.
+//
+//                NOTE WELL!!
+//
+// See orderAccess.hpp.  We assume throughout the VM that MutexLocker's
+// and friends constructors do a fence, a lock and an acquire *in that
+// order*.  And that their destructors do a release and unlock, in *that*
+// order.  If their implementations change such that these assumptions
+// are violated, a whole lot of code will break.
+
+// Print all mutexes/monitors that are currently owned by a thread; called
+// by fatal error handler.
+void print_owned_locks_on_error(outputStream* st);
+
+char *lock_name(Mutex *mutex);
+
+class MutexLocker: StackObj {
+ private:
+  Monitor * _mutex;
+ public:
+  MutexLocker(Monitor * mutex) {
+    assert(mutex->rank() != Mutex::special,
+      "Special ranked mutex should only use MutexLockerEx");
+    _mutex = mutex;
+    _mutex->lock();
+  }
+
+  // Overloaded constructor passing current thread
+  MutexLocker(Monitor * mutex, Thread *thread) {
+    assert(mutex->rank() != Mutex::special,
+      "Special ranked mutex should only use MutexLockerEx");
+    _mutex = mutex;
+    _mutex->lock(thread);
+  }
+
+  ~MutexLocker() {
+    _mutex->unlock();
+  }
+
+};
+
+// for debugging: check that we're already owning this lock (or are at a safepoint)
+#ifdef ASSERT
+void assert_locked_or_safepoint(const Monitor * lock);
+void assert_lock_strong(const Monitor * lock);
+#else
+#define assert_locked_or_safepoint(lock)
+#define assert_lock_strong(lock)
+#endif
+
+// A MutexLockerEx behaves like a MutexLocker when its constructor is
+// called with a Mutex.  Unlike a MutexLocker, its constructor can also be
+// called with NULL, in which case the MutexLockerEx is a no-op.  There
+// is also a corresponding MutexUnlockerEx.  We want to keep the
+// basic MutexLocker as fast as possible.  MutexLockerEx can also lock
+// without safepoint check.
+
+class MutexLockerEx: public StackObj {
+ private:
+  Monitor * _mutex;
+ public:
+  MutexLockerEx(Monitor * mutex, bool no_safepoint_check = !Mutex::_no_safepoint_check_flag) {
+    _mutex = mutex;
+    if (_mutex != NULL) {
+      assert(mutex->rank() > Mutex::special || no_safepoint_check,
+        "Mutexes with rank special or lower should not do safepoint checks");
+      if (no_safepoint_check)
+        _mutex->lock_without_safepoint_check();
+      else
+        _mutex->lock();
+    }
+  }
+
+  ~MutexLockerEx() {
+    if (_mutex != NULL) {
+      _mutex->unlock();
+    }
+  }
+};
+
+// A MonitorLockerEx is like a MutexLockerEx above, except it takes
+// a possibly null Monitor, and allows wait/notify as well which are
+// delegated to the underlying Monitor.
+
+class MonitorLockerEx: public MutexLockerEx {
+ private:
+  Monitor * _monitor;
+ public:
+  MonitorLockerEx(Monitor* monitor,
+                  bool no_safepoint_check = !Mutex::_no_safepoint_check_flag):
+    MutexLockerEx(monitor, no_safepoint_check),
+    _monitor(monitor) {
+    // Superclass constructor did locking
+  }
+
+  ~MonitorLockerEx() {
+    #ifdef ASSERT
+      if (_monitor != NULL) {
+        assert_lock_strong(_monitor);
+      }
+    #endif  // ASSERT
+    // Superclass destructor will do unlocking
+  }
+
+  bool wait(bool no_safepoint_check = !Mutex::_no_safepoint_check_flag,
+            long timeout = 0,
+            bool as_suspend_equivalent = !Mutex::_as_suspend_equivalent_flag) {
+    if (_monitor != NULL) {
+      return _monitor->wait(no_safepoint_check, timeout, as_suspend_equivalent);
+    }
+    return false;
+  }
+
+  bool notify_all() {
+    if (_monitor != NULL) {
+      return _monitor->notify_all();
+    }
+    return true;
+  }
+
+  bool notify() {
+    if (_monitor != NULL) {
+      return _monitor->notify();
+    }
+    return true;
+  }
+};
+
+
+
+// A GCMutexLocker is usually initialized with a mutex that is
+// automatically acquired in order to do GC.  The function that
+// synchronizes using a GCMutexLocker may be called both during and between
+// GC's.  Thus, it must acquire the mutex if GC is not in progress, but not
+// if GC is in progress (since the mutex is already held on its behalf.)
+
+class GCMutexLocker: public StackObj {
+private:
+  Monitor * _mutex;
+  bool _locked;
+public:
+  GCMutexLocker(Monitor * mutex);
+  ~GCMutexLocker() { if (_locked) _mutex->unlock(); }
+};
+
+
+
+// A MutexUnlocker temporarily exits a previously
+// entered mutex for the scope which contains the unlocker.
+
+class MutexUnlocker: StackObj {
+ private:
+  Monitor * _mutex;
+
+ public:
+  MutexUnlocker(Monitor * mutex) {
+    _mutex = mutex;
+    _mutex->unlock();
+  }
+
+  ~MutexUnlocker() {
+    _mutex->lock();
+  }
+};
+
+// A MutexUnlockerEx temporarily exits a previously
+// entered mutex for the scope which contains the unlocker.
+
+class MutexUnlockerEx: StackObj {
+ private:
+  Monitor * _mutex;
+  bool _no_safepoint_check;
+
+ public:
+  MutexUnlockerEx(Monitor * mutex, bool no_safepoint_check = !Mutex::_no_safepoint_check_flag) {
+    _mutex = mutex;
+    _no_safepoint_check = no_safepoint_check;
+    _mutex->unlock();
+  }
+
+  ~MutexUnlockerEx() {
+    if (_no_safepoint_check == Mutex::_no_safepoint_check_flag) {
+      _mutex->lock_without_safepoint_check();
+    } else {
+      _mutex->lock();
+    }
+  }
+};
+
+#ifndef PRODUCT
+//
+// A special MutexLocker that allows:
+//   - reentrant locking
+//   - locking out of order
+//
+// Only too be used for verify code, where we can relaxe out dead-lock
+// dection code a bit (unsafe, but probably ok). This code is NEVER to
+// be included in a product version.
+//
+class VerifyMutexLocker: StackObj {
+ private:
+  Monitor * _mutex;
+  bool   _reentrant;
+ public:
+  VerifyMutexLocker(Monitor * mutex) {
+    _mutex     = mutex;
+    _reentrant = mutex->owned_by_self();
+    if (!_reentrant) {
+      // We temp. diable strict safepoint checking, while we require the lock
+      FlagSetting fs(StrictSafepointChecks, false);
+      _mutex->lock();
+    }
+  }
+
+  ~VerifyMutexLocker() {
+    if (!_reentrant) {
+      _mutex->unlock();
+    }
+  }
+};
+
+#endif