hotspot/src/share/vm/prims/jvmtiImpl.hpp
changeset 1 489c9b5090e2
child 2137 b03f1da1a3d3
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/hotspot/src/share/vm/prims/jvmtiImpl.hpp	Sat Dec 01 00:00:00 2007 +0000
@@ -0,0 +1,477 @@
+/*
+ * Copyright 1999-2007 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.
+ *
+ */
+
+//
+// Forward Declarations
+//
+
+class JvmtiRawMonitor;
+class JvmtiBreakpoint;
+class JvmtiBreakpoints;
+
+
+///////////////////////////////////////////////////////////////
+//
+// class GrowableCache, GrowableElement
+// Used by              : JvmtiBreakpointCache
+// Used by JVMTI methods: none directly.
+//
+// GrowableCache is a permanent CHeap growable array of <GrowableElement *>
+//
+// In addition, the GrowableCache maintains a NULL terminated cache array of type address
+// that's created from the element array using the function:
+//     address GrowableElement::getCacheValue().
+//
+// Whenever the GrowableArray changes size, the cache array gets recomputed into a new C_HEAP allocated
+// block of memory. Additionally, every time the cache changes its position in memory, the
+//    void (*_listener_fun)(void *this_obj, address* cache)
+// gets called with the cache's new address. This gives the user of the GrowableCache a callback
+// to update its pointer to the address cache.
+//
+
+class GrowableElement : public CHeapObj {
+public:
+  virtual address getCacheValue()          =0;
+  virtual bool equals(GrowableElement* e)  =0;
+  virtual bool lessThan(GrowableElement *e)=0;
+  virtual GrowableElement *clone()         =0;
+  virtual void oops_do(OopClosure* f)      =0;
+};
+
+class GrowableCache VALUE_OBJ_CLASS_SPEC {
+
+private:
+  // Object pointer passed into cache & listener functions.
+  void *_this_obj;
+
+  // Array of elements in the collection
+  GrowableArray<GrowableElement *> *_elements;
+
+  // Parallel array of cached values
+  address *_cache;
+
+  // Listener for changes to the _cache field.
+  // Called whenever the _cache field has it's value changed
+  // (but NOT when cached elements are recomputed).
+  void (*_listener_fun)(void *, address*);
+
+  static bool equals(void *, GrowableElement *);
+
+  // recache all elements after size change, notify listener
+  void recache();
+
+public:
+   GrowableCache();
+   ~GrowableCache();
+
+  void initialize(void *this_obj, void listener_fun(void *, address*) );
+
+  // number of elements in the collection
+  int length();
+  // get the value of the index element in the collection
+  GrowableElement* at(int index);
+  // find the index of the element, -1 if it doesn't exist
+  int find(GrowableElement* e);
+  // append a copy of the element to the end of the collection, notify listener
+  void append(GrowableElement* e);
+  // insert a copy of the element using lessthan(), notify listener
+  void insert(GrowableElement* e);
+  // remove the element at index, notify listener
+  void remove (int index);
+  // clear out all elements and release all heap space, notify listener
+  void clear();
+  // apply f to every element and update the cache
+  void oops_do(OopClosure* f);
+  void gc_epilogue();
+};
+
+
+///////////////////////////////////////////////////////////////
+//
+// class JvmtiBreakpointCache
+// Used by              : JvmtiBreakpoints
+// Used by JVMTI methods: none directly.
+// Note   : typesafe wrapper for GrowableCache of JvmtiBreakpoint
+//
+
+class JvmtiBreakpointCache : public CHeapObj {
+
+private:
+  GrowableCache _cache;
+
+public:
+  JvmtiBreakpointCache()  {}
+  ~JvmtiBreakpointCache() {}
+
+  void initialize(void *this_obj, void listener_fun(void *, address*) ) {
+    _cache.initialize(this_obj,listener_fun);
+  }
+
+  int length()                          { return _cache.length(); }
+  JvmtiBreakpoint& at(int index)        { return (JvmtiBreakpoint&) *(_cache.at(index)); }
+  int find(JvmtiBreakpoint& e)          { return _cache.find((GrowableElement *) &e); }
+  void append(JvmtiBreakpoint& e)       { _cache.append((GrowableElement *) &e); }
+  void remove (int index)               { _cache.remove(index); }
+  void clear()                          { _cache.clear(); }
+  void oops_do(OopClosure* f)           { _cache.oops_do(f); }
+  void gc_epilogue()                    { _cache.gc_epilogue(); }
+};
+
+
+///////////////////////////////////////////////////////////////
+//
+// class JvmtiBreakpoint
+// Used by              : JvmtiBreakpoints
+// Used by JVMTI methods: SetBreakpoint, ClearBreakpoint, ClearAllBreakpoints
+// Note: Extends GrowableElement for use in a GrowableCache
+//
+// A JvmtiBreakpoint describes a location (class, method, bci) to break at.
+//
+
+typedef void (methodOopDesc::*method_action)(int _bci);
+
+class JvmtiBreakpoint : public GrowableElement {
+private:
+  methodOop             _method;
+  int                   _bci;
+  Bytecodes::Code       _orig_bytecode;
+
+public:
+  JvmtiBreakpoint();
+  JvmtiBreakpoint(methodOop m_method, jlocation location);
+  bool equals(JvmtiBreakpoint& bp);
+  bool lessThan(JvmtiBreakpoint &bp);
+  void copy(JvmtiBreakpoint& bp);
+  bool is_valid();
+  address getBcp();
+  void each_method_version_do(method_action meth_act);
+  void set();
+  void clear();
+  void print();
+
+  methodOop method() { return _method; }
+
+  // GrowableElement implementation
+  address getCacheValue()         { return getBcp(); }
+  bool lessThan(GrowableElement* e) { Unimplemented(); return false; }
+  bool equals(GrowableElement* e) { return equals((JvmtiBreakpoint&) *e); }
+  void oops_do(OopClosure* f)     { f->do_oop((oop *) &_method); }
+  GrowableElement *clone()        {
+    JvmtiBreakpoint *bp = new JvmtiBreakpoint();
+    bp->copy(*this);
+    return bp;
+  }
+};
+
+
+///////////////////////////////////////////////////////////////
+//
+// class VM_ChangeBreakpoints
+// Used by              : JvmtiBreakpoints
+// Used by JVMTI methods: none directly.
+// Note: A Helper class.
+//
+// VM_ChangeBreakpoints implements a VM_Operation for ALL modifications to the JvmtiBreakpoints class.
+//
+
+class VM_ChangeBreakpoints : public VM_Operation {
+private:
+  JvmtiBreakpoints* _breakpoints;
+  int               _operation;
+  JvmtiBreakpoint*  _bp;
+
+public:
+  enum { SET_BREAKPOINT=0, CLEAR_BREAKPOINT=1, CLEAR_ALL_BREAKPOINT=2 };
+
+  VM_ChangeBreakpoints(JvmtiBreakpoints* breakpoints, int operation) {
+    _breakpoints = breakpoints;
+    _bp = NULL;
+    _operation = operation;
+    assert(breakpoints != NULL, "breakpoints != NULL");
+    assert(operation == CLEAR_ALL_BREAKPOINT, "unknown breakpoint operation");
+  }
+  VM_ChangeBreakpoints(JvmtiBreakpoints* breakpoints, int operation, JvmtiBreakpoint *bp) {
+    _breakpoints = breakpoints;
+    _bp = bp;
+    _operation = operation;
+    assert(breakpoints != NULL, "breakpoints != NULL");
+    assert(bp != NULL, "bp != NULL");
+    assert(operation == SET_BREAKPOINT || operation == CLEAR_BREAKPOINT , "unknown breakpoint operation");
+  }
+
+  VMOp_Type type() const { return VMOp_ChangeBreakpoints; }
+  void doit();
+  void oops_do(OopClosure* f);
+};
+
+
+///////////////////////////////////////////////////////////////
+//
+// class JvmtiBreakpoints
+// Used by              : JvmtiCurrentBreakpoints
+// Used by JVMTI methods: none directly
+// Note: A Helper class
+//
+// JvmtiBreakpoints is a GrowableCache of JvmtiBreakpoint.
+// All changes to the GrowableCache occur at a safepoint using VM_ChangeBreakpoints.
+//
+// Because _bps is only modified at safepoints, its possible to always use the
+// cached byte code pointers from _bps without doing any synchronization (see JvmtiCurrentBreakpoints).
+//
+// It would be possible to make JvmtiBreakpoints a static class, but I've made it
+// CHeap allocated to emphasize its similarity to JvmtiFramePops.
+//
+
+class JvmtiBreakpoints : public CHeapObj {
+private:
+
+  JvmtiBreakpointCache _bps;
+
+  // These should only be used by VM_ChangeBreakpoints
+  // to insure they only occur at safepoints.
+  // Todo: add checks for safepoint
+  friend class VM_ChangeBreakpoints;
+  void set_at_safepoint(JvmtiBreakpoint& bp);
+  void clear_at_safepoint(JvmtiBreakpoint& bp);
+  void clearall_at_safepoint();
+
+  static void do_element(GrowableElement *e);
+
+public:
+  JvmtiBreakpoints(void listener_fun(void *, address *));
+  ~JvmtiBreakpoints();
+
+  int length();
+  void oops_do(OopClosure* f);
+  void gc_epilogue();
+  void print();
+
+  int  set(JvmtiBreakpoint& bp);
+  int  clear(JvmtiBreakpoint& bp);
+  void clearall_in_class_at_safepoint(klassOop klass);
+  void clearall();
+};
+
+
+///////////////////////////////////////////////////////////////
+//
+// class JvmtiCurrentBreakpoints
+//
+// A static wrapper class for the JvmtiBreakpoints that provides:
+// 1. a fast inlined function to check if a byte code pointer is a breakpoint (is_breakpoint).
+// 2. a function for lazily creating the JvmtiBreakpoints class (this is not strictly necessary,
+//    but I'm copying the code from JvmtiThreadState which needs to lazily initialize
+//    JvmtiFramePops).
+// 3. An oops_do entry point for GC'ing the breakpoint array.
+//
+
+class JvmtiCurrentBreakpoints : public AllStatic {
+
+private:
+
+  // Current breakpoints, lazily initialized by get_jvmti_breakpoints();
+  static JvmtiBreakpoints *_jvmti_breakpoints;
+
+  // NULL terminated cache of byte-code pointers corresponding to current breakpoints.
+  // Updated only at safepoints (with listener_fun) when the cache is moved.
+  // It exists only to make is_breakpoint fast.
+  static address          *_breakpoint_list;
+  static inline void set_breakpoint_list(address *breakpoint_list) { _breakpoint_list = breakpoint_list; }
+  static inline address *get_breakpoint_list()                     { return _breakpoint_list; }
+
+  // Listener for the GrowableCache in _jvmti_breakpoints, updates _breakpoint_list.
+  static void listener_fun(void *this_obj, address *cache);
+
+public:
+  static void initialize();
+  static void destroy();
+
+  // lazily create _jvmti_breakpoints and _breakpoint_list
+  static JvmtiBreakpoints& get_jvmti_breakpoints();
+
+  // quickly test whether the bcp matches a cached breakpoint in the list
+  static inline bool is_breakpoint(address bcp);
+
+  static void oops_do(OopClosure* f);
+  static void gc_epilogue();
+};
+
+// quickly test whether the bcp matches a cached breakpoint in the list
+bool JvmtiCurrentBreakpoints::is_breakpoint(address bcp) {
+    address *bps = get_breakpoint_list();
+    if (bps == NULL) return false;
+    for ( ; (*bps) != NULL; bps++) {
+      if ((*bps) == bcp) return true;
+    }
+    return false;
+}
+
+
+///////////////////////////////////////////////////////////////
+//
+// class JvmtiRawMonitor
+//
+// Used by JVMTI methods: All RawMonitor methods (CreateRawMonitor, EnterRawMonitor, etc.)
+//
+// Wrapper for ObjectMonitor class that saves the Monitor's name
+//
+
+class JvmtiRawMonitor : public ObjectMonitor  {
+private:
+  int           _magic;
+  char *        _name;
+  // JVMTI_RM_MAGIC is set in contructor and unset in destructor.
+  enum { JVMTI_RM_MAGIC = (int)(('T' << 24) | ('I' << 16) | ('R' << 8) | 'M') };
+
+public:
+  JvmtiRawMonitor(const char *name);
+  ~JvmtiRawMonitor();
+  int            magic()   { return _magic;  }
+  const char *get_name()   { return _name; }
+  bool        is_valid()   { return _magic == JVMTI_RM_MAGIC;  }
+};
+
+// Onload pending raw monitors
+// Class is used to cache onload or onstart monitor enter
+// which will transition into real monitor when
+// VM is fully initialized.
+class JvmtiPendingMonitors : public AllStatic {
+
+private:
+  static GrowableArray<JvmtiRawMonitor*> *_monitors; // Cache raw monitor enter
+
+  inline static GrowableArray<JvmtiRawMonitor*>* monitors() { return _monitors; }
+
+  static void dispose() {
+    delete monitors();
+  }
+
+public:
+  static void enter(JvmtiRawMonitor *monitor) {
+    monitors()->append(monitor);
+  }
+
+  static int count() {
+    return monitors()->length();
+  }
+
+  static void destroy(JvmtiRawMonitor *monitor) {
+    while (monitors()->contains(monitor)) {
+      monitors()->remove(monitor);
+    }
+  }
+
+  // Return false if monitor is not found in the list.
+  static bool exit(JvmtiRawMonitor *monitor) {
+    if (monitors()->contains(monitor)) {
+      monitors()->remove(monitor);
+      return true;
+    } else {
+      return false;
+    }
+  }
+
+  static void transition_raw_monitors();
+};
+
+
+
+///////////////////////////////////////////////////////////////
+// The get/set local operations must only be done by the VM thread
+// because the interpreter version needs to access oop maps, which can
+// only safely be done by the VM thread
+//
+// I'm told that in 1.5 oop maps are now protected by a lock and
+// we could get rid of the VM op
+// However if the VM op is removed then the target thread must
+// be suspended AND a lock will be needed to prevent concurrent
+// setting of locals to the same java thread. This lock is needed
+// to prevent compiledVFrames from trying to add deferred updates
+// to the thread simultaneously.
+//
+class VM_GetOrSetLocal : public VM_Operation {
+private:
+  JavaThread* _thread;
+  JavaThread* _calling_thread;
+  jint        _depth;
+  jint        _index;
+  BasicType   _type;
+  jvalue      _value;
+  javaVFrame* _jvf;
+  bool        _set;
+
+  jvmtiError  _result;
+
+  vframe* get_vframe();
+  javaVFrame* get_java_vframe();
+  bool check_slot_type(javaVFrame* vf);
+
+public:
+  // Constructor for non-object getter
+  VM_GetOrSetLocal(JavaThread* thread, jint depth, jint index, BasicType type);
+
+  // Constructor for object or non-object setter
+  VM_GetOrSetLocal(JavaThread* thread, jint depth, jint index, BasicType type, jvalue value);
+
+  // Constructor for object getter
+  VM_GetOrSetLocal(JavaThread* thread, JavaThread* calling_thread, jint depth,
+                   int index);
+
+  VMOp_Type type() const { return VMOp_GetOrSetLocal; }
+  jvalue value()         { return _value; }
+  jvmtiError result()    { return _result; }
+
+  bool doit_prologue();
+  void doit();
+  bool allow_nested_vm_operations() const;
+  const char* name() const                       { return "get/set locals"; }
+
+  // Check that the klass is assignable to a type with the given signature.
+  static bool is_assignable(const char* ty_sign, Klass* klass, Thread* thread);
+};
+
+
+///////////////////////////////////////////////////////////////
+//
+// class JvmtiSuspendControl
+//
+// Convenience routines for suspending and resuming threads.
+//
+// All attempts by JVMTI to suspend and resume threads must go through the
+// JvmtiSuspendControl interface.
+//
+// methods return true if successful
+//
+class JvmtiSuspendControl : public AllStatic {
+public:
+  // suspend the thread, taking it to a safepoint
+  static bool suspend(JavaThread *java_thread);
+  // resume the thread
+  static bool resume(JavaThread *java_thread);
+
+  static void print();
+};
+
+// Utility macro that checks for NULL pointers:
+#define NULL_CHECK(X, Y) if ((X) == NULL) { return (Y); }