diff -r 4ebc2e2fb97c -r 71c04702a3d5 src/hotspot/share/prims/jvmtiImpl.hpp --- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/src/hotspot/share/prims/jvmtiImpl.hpp Tue Sep 12 19:03:39 2017 +0200 @@ -0,0 +1,534 @@ +/* + * Copyright (c) 1999, 2017, 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_PRIMS_JVMTIIMPL_HPP +#define SHARE_VM_PRIMS_JVMTIIMPL_HPP + +#include "classfile/systemDictionary.hpp" +#include "jvmtifiles/jvmti.h" +#include "oops/objArrayOop.hpp" +#include "prims/jvmtiEnvThreadState.hpp" +#include "prims/jvmtiEventController.hpp" +#include "prims/jvmtiTrace.hpp" +#include "prims/jvmtiUtil.hpp" +#include "runtime/stackValueCollection.hpp" +#include "runtime/vm_operations.hpp" +#include "utilities/ostream.hpp" + +// +// Forward Declarations +// + +class JvmtiBreakpoint; +class JvmtiBreakpoints; + + +/////////////////////////////////////////////////////////////// +// +// class GrowableCache, GrowableElement +// Used by : JvmtiBreakpointCache +// Used by JVMTI methods: none directly. +// +// GrowableCache is a permanent CHeap growable array of +// +// 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 ~GrowableElement() {} + 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; + virtual void metadata_do(void f(Metadata*)) =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 *_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); + // walk metadata to preserve for RedefineClasses + void metadata_do(void f(Metadata*)); + // update the cache after a full gc + 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 metadata_do(void f(Metadata*)) { _cache.metadata_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 (Method::*method_action)(int _bci); + +class JvmtiBreakpoint : public GrowableElement { +private: + Method* _method; + int _bci; + Bytecodes::Code _orig_bytecode; + oop _class_holder; // keeps _method memory from being deallocated + +public: + JvmtiBreakpoint(); + JvmtiBreakpoint(Method* m_method, jlocation location); + bool equals(JvmtiBreakpoint& bp); + bool lessThan(JvmtiBreakpoint &bp); + void copy(JvmtiBreakpoint& bp); + bool is_valid(); + address getBcp() const; + void each_method_version_do(method_action meth_act); + void set(); + void clear(); + void print_on(outputStream* out) const; + + Method* 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) { + // Mark the method loader as live so the Method* class loader doesn't get + // unloaded and Method* memory reclaimed. + f->do_oop(&_class_holder); + } + void metadata_do(void f(Metadata*)) { + // walk metadata to preserve for RedefineClasses + f(_method); + } + + GrowableElement *clone() { + JvmtiBreakpoint *bp = new JvmtiBreakpoint(); + bp->copy(*this); + return bp; + } +}; + + +/////////////////////////////////////////////////////////////// +// +// 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); + + static void do_element(GrowableElement *e); + +public: + JvmtiBreakpoints(void listener_fun(void *, address *)); + ~JvmtiBreakpoints(); + + int length(); + void oops_do(OopClosure* f); + void metadata_do(void f(Metadata*)); + void print(); + + int set(JvmtiBreakpoint& bp); + int clear(JvmtiBreakpoint& bp); + void clearall_in_class_at_safepoint(Klass* klass); + void gc_epilogue(); +}; + + +/////////////////////////////////////////////////////////////// +// +// 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 metadata_do(void f(Metadata*)) NOT_JVMTI_RETURN; + 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 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 }; + + VM_ChangeBreakpoints(int operation, JvmtiBreakpoint *bp) { + JvmtiBreakpoints& current_bps = JvmtiCurrentBreakpoints::get_jvmti_breakpoints(); + _breakpoints = ¤t_bps; + _bp = bp; + _operation = operation; + assert(bp != NULL, "bp != NULL"); + } + + VMOp_Type type() const { return VMOp_ChangeBreakpoints; } + void doit(); + void oops_do(OopClosure* f); + void metadata_do(void f(Metadata*)); +}; + + +/////////////////////////////////////////////////////////////// +// 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 { + protected: + JavaThread* _thread; + JavaThread* _calling_thread; + jint _depth; + jint _index; + BasicType _type; + jvalue _value; + javaVFrame* _jvf; + bool _set; + + // It is possible to get the receiver out of a non-static native wrapper + // frame. Use VM_GetReceiver to do this. + virtual bool getting_receiver() const { return false; } + + 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 VM_GetReceiver : public VM_GetOrSetLocal { + protected: + virtual bool getting_receiver() const { return true; } + + public: + VM_GetReceiver(JavaThread* thread, JavaThread* calling_thread, jint depth); + const char* name() const { return "get receiver"; } +}; + + +/////////////////////////////////////////////////////////////// +// +// 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(); +}; + + +/** + * When a thread (such as the compiler thread or VM thread) cannot post a + * JVMTI event itself because the event needs to be posted from a Java + * thread, then it can defer the event to the Service thread for posting. + * The information needed to post the event is encapsulated into this class + * and then enqueued onto the JvmtiDeferredEventQueue, where the Service + * thread will pick it up and post it. + * + * This is currently only used for posting compiled-method-load and unload + * events, which we don't want posted from the compiler thread. + */ +class JvmtiDeferredEvent VALUE_OBJ_CLASS_SPEC { + friend class JvmtiDeferredEventQueue; + private: + typedef enum { + TYPE_NONE, + TYPE_COMPILED_METHOD_LOAD, + TYPE_COMPILED_METHOD_UNLOAD, + TYPE_DYNAMIC_CODE_GENERATED + } Type; + + Type _type; + union { + nmethod* compiled_method_load; + struct { + nmethod* nm; + jmethodID method_id; + const void* code_begin; + } compiled_method_unload; + struct { + const char* name; + const void* code_begin; + const void* code_end; + } dynamic_code_generated; + } _event_data; + + JvmtiDeferredEvent(Type t) : _type(t) {} + + public: + + JvmtiDeferredEvent() : _type(TYPE_NONE) {} + + // Factory methods + static JvmtiDeferredEvent compiled_method_load_event(nmethod* nm) + NOT_JVMTI_RETURN_(JvmtiDeferredEvent()); + static JvmtiDeferredEvent compiled_method_unload_event(nmethod* nm, + jmethodID id, const void* code) NOT_JVMTI_RETURN_(JvmtiDeferredEvent()); + static JvmtiDeferredEvent dynamic_code_generated_event( + const char* name, const void* begin, const void* end) + NOT_JVMTI_RETURN_(JvmtiDeferredEvent()); + + // Actually posts the event. + void post() NOT_JVMTI_RETURN; +}; + +/** + * Events enqueued on this queue wake up the Service thread which dequeues + * and posts the events. The Service_lock is required to be held + * when operating on the queue. + */ +class JvmtiDeferredEventQueue : AllStatic { + friend class JvmtiDeferredEvent; + private: + class QueueNode : public CHeapObj { + private: + JvmtiDeferredEvent _event; + QueueNode* _next; + + public: + QueueNode(const JvmtiDeferredEvent& event) + : _event(event), _next(NULL) {} + + const JvmtiDeferredEvent& event() const { return _event; } + QueueNode* next() const { return _next; } + + void set_next(QueueNode* next) { _next = next; } + }; + + static QueueNode* _queue_head; // Hold Service_lock to access + static QueueNode* _queue_tail; // Hold Service_lock to access + + public: + // Must be holding Service_lock when calling these + static bool has_events() NOT_JVMTI_RETURN_(false); + static void enqueue(const JvmtiDeferredEvent& event) NOT_JVMTI_RETURN; + static JvmtiDeferredEvent dequeue() NOT_JVMTI_RETURN_(JvmtiDeferredEvent()); +}; + +// Utility macro that checks for NULL pointers: +#define NULL_CHECK(X, Y) if ((X) == NULL) { return (Y); } + +#endif // SHARE_VM_PRIMS_JVMTIIMPL_HPP