src/hotspot/share/prims/jvmtiThreadState.hpp
changeset 47216 71c04702a3d5
parent 46329 53ccc37bda19
child 47580 96392e113a0a
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/src/hotspot/share/prims/jvmtiThreadState.hpp	Tue Sep 12 19:03:39 2017 +0200
@@ -0,0 +1,433 @@
+/*
+ * Copyright (c) 2003, 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_JVMTITHREADSTATE_HPP
+#define SHARE_VM_PRIMS_JVMTITHREADSTATE_HPP
+
+#include "jvmtifiles/jvmti.h"
+#include "memory/allocation.hpp"
+#include "memory/allocation.inline.hpp"
+#include "prims/jvmtiEventController.hpp"
+#include "runtime/thread.hpp"
+#include "utilities/growableArray.hpp"
+
+//
+// Forward Declarations
+//
+
+class JvmtiEnvBase;
+class JvmtiEnvThreadState;
+class JvmtiDynamicCodeEventCollector;
+
+enum JvmtiClassLoadKind {
+  jvmti_class_load_kind_load = 100,
+  jvmti_class_load_kind_retransform,
+  jvmti_class_load_kind_redefine
+};
+
+///////////////////////////////////////////////////////////////
+//
+// class JvmtiEnvThreadStateIterator
+//
+// The only safe means of iterating through the JvmtiEnvThreadStates
+// in a JvmtiThreadState.
+// Note that this iteratation includes invalid environments pending
+// deallocation -- in fact, some uses depend on this behavior.
+//
+class JvmtiEnvThreadStateIterator : public StackObj {
+ private:
+  JvmtiThreadState* state;
+ public:
+  JvmtiEnvThreadStateIterator(JvmtiThreadState* thread_state);
+  ~JvmtiEnvThreadStateIterator();
+  JvmtiEnvThreadState* first();
+  JvmtiEnvThreadState* next(JvmtiEnvThreadState* ets);
+};
+
+
+///////////////////////////////////////////////////////////////
+//
+// class JvmtiThreadState
+//
+// The Jvmti state for each thread (across all JvmtiEnv):
+// 1. Local table of enabled events.
+class JvmtiThreadState : public CHeapObj<mtInternal> {
+ private:
+  friend class JvmtiEnv;
+  JavaThread        *_thread;
+  bool              _hide_single_stepping;
+  bool              _pending_step_for_popframe;
+  bool              _pending_step_for_earlyret;
+  int               _hide_level;
+
+ public:
+  enum ExceptionState {
+    ES_CLEARED,
+    ES_DETECTED,
+    ES_CAUGHT
+  };
+
+ private:
+  ExceptionState _exception_state;
+
+  // Used to send class being redefined/retransformed and kind of transform
+  // info to the class file load hook event handler.
+  Klass*                _class_being_redefined;
+  JvmtiClassLoadKind    _class_load_kind;
+
+  // This is only valid when is_interp_only_mode() returns true
+  int               _cur_stack_depth;
+
+  JvmtiThreadEventEnable _thread_event_enable;
+
+  // for support of JvmtiEnvThreadState
+  JvmtiEnvThreadState*   _head_env_thread_state;
+
+  // doubly-linked linear list of active thread state
+  // needed in order to iterate the list without holding Threads_lock
+  static JvmtiThreadState *_head;
+  JvmtiThreadState *_next;
+  JvmtiThreadState *_prev;
+
+  // holds the current dynamic code event collector, NULL if no event collector in use
+  JvmtiDynamicCodeEventCollector* _dynamic_code_event_collector;
+  // holds the current vm object alloc event collector, NULL if no event collector in use
+  JvmtiVMObjectAllocEventCollector* _vm_object_alloc_event_collector;
+
+  // Should only be created by factory methods
+  JvmtiThreadState(JavaThread *thread);
+
+  friend class JvmtiEnvThreadStateIterator;
+  inline JvmtiEnvThreadState* head_env_thread_state();
+  inline void set_head_env_thread_state(JvmtiEnvThreadState* ets);
+
+ public:
+  ~JvmtiThreadState();
+
+  // is event_type enabled and usable for this thread in any enviroments?
+  bool is_enabled(jvmtiEvent event_type) {
+    return _thread_event_enable.is_enabled(event_type);
+  }
+
+  JvmtiThreadEventEnable *thread_event_enable() {
+    return &_thread_event_enable;
+  }
+
+  // Must only be called in situations where the state is for the current thread and
+  // the environment can not go away.  To be safe, the returned JvmtiEnvThreadState
+  // must be used in such a way as there can be no intervening safepoints.
+  inline JvmtiEnvThreadState* env_thread_state(JvmtiEnvBase *env);
+
+  static void periodic_clean_up();
+
+  void add_env(JvmtiEnvBase *env);
+
+  // Used by the interpreter for fullspeed debugging support
+  bool is_interp_only_mode()                { return _thread->is_interp_only_mode(); }
+  void enter_interp_only_mode();
+  void leave_interp_only_mode();
+
+  // access to the linked list of all JVMTI thread states
+  static JvmtiThreadState *first() {
+    assert(Threads::number_of_threads() == 0 || JvmtiThreadState_lock->is_locked(), "sanity check");
+    return _head;
+  }
+
+  JvmtiThreadState *next()                  {
+    return _next;
+  }
+
+  // Current stack depth is only valid when is_interp_only_mode() returns true.
+  // These functions should only be called at a safepoint - usually called from same thread.
+  // Returns the number of Java activations on the stack.
+  int cur_stack_depth();
+  void invalidate_cur_stack_depth();
+  void incr_cur_stack_depth();
+  void decr_cur_stack_depth();
+
+  int count_frames();
+
+  inline JavaThread *get_thread()      { return _thread;              }
+
+  inline bool is_exception_detected()  { return _exception_state == ES_DETECTED;  }
+  inline bool is_exception_caught()    { return _exception_state == ES_CAUGHT;  }
+
+  inline void set_exception_detected() { _exception_state = ES_DETECTED; }
+  inline void set_exception_caught()   { _exception_state = ES_CAUGHT; }
+
+  inline void clear_exception_state() { _exception_state = ES_CLEARED; }
+
+  // We need to save and restore exception state inside JvmtiEventMark
+  inline ExceptionState get_exception_state() { return _exception_state; }
+  inline void restore_exception_state(ExceptionState state) { _exception_state = state; }
+
+  inline void clear_hide_single_stepping() {
+    if (_hide_level > 0) {
+      _hide_level--;
+    } else {
+      assert(_hide_single_stepping, "hide_single_stepping is out of phase");
+      _hide_single_stepping = false;
+    }
+  }
+  inline bool hide_single_stepping() { return _hide_single_stepping; }
+  inline void set_hide_single_stepping() {
+    if (_hide_single_stepping) {
+      _hide_level++;
+    } else {
+      assert(_hide_level == 0, "hide_level is out of phase");
+      _hide_single_stepping = true;
+    }
+  }
+
+  // Step pending flag is set when PopFrame is called and it is cleared
+  // when step for the Pop Frame is completed.
+  // This logic is used to distinguish b/w step for pop frame and repeat step.
+  void set_pending_step_for_popframe() { _pending_step_for_popframe = true;  }
+  void clr_pending_step_for_popframe() { _pending_step_for_popframe = false; }
+  bool is_pending_step_for_popframe()  { return _pending_step_for_popframe;  }
+  void process_pending_step_for_popframe();
+
+  // Step pending flag is set when ForceEarlyReturn is called and it is cleared
+  // when step for the ForceEarlyReturn is completed.
+  // This logic is used to distinguish b/w step for early return and repeat step.
+  void set_pending_step_for_earlyret() { _pending_step_for_earlyret = true;  }
+  void clr_pending_step_for_earlyret() { _pending_step_for_earlyret = false; }
+  bool is_pending_step_for_earlyret()  { return _pending_step_for_earlyret;  }
+  void process_pending_step_for_earlyret();
+
+  // Setter and getter method is used to send redefined class info
+  // when class file load hook event is posted.
+  // It is set while loading redefined class and cleared before the
+  // class file load hook event is posted.
+  inline void set_class_being_redefined(Klass* k, JvmtiClassLoadKind kind) {
+    _class_being_redefined = k;
+    _class_load_kind = kind;
+  }
+
+  inline void clear_class_being_redefined() {
+    _class_being_redefined = NULL;
+    _class_load_kind = jvmti_class_load_kind_load;
+  }
+
+  inline Klass* get_class_being_redefined() {
+    return _class_being_redefined;
+  }
+
+  inline JvmtiClassLoadKind get_class_load_kind() {
+    return _class_load_kind;
+  }
+
+  // RedefineClasses support
+  // The bug 6214132 caused the verification to fail.
+  //
+  // Below is the detailed description of the fix approach taken:
+  // 1. What's done in RedefineClasses() before verification:
+  //  a) A reference to the class being redefined (_the_class) and a
+  //     reference to new version of the class (_scratch_class) are
+  //     saved here for use during the bytecode verification phase of
+  //     RedefineClasses. See RedefineVerifyMark for how these fields
+  //     are managed.
+  //   b) The _java_mirror field from _the_class is copied to the
+  //     _java_mirror field in _scratch_class. This means that a jclass
+  //     returned for _the_class or _scratch_class will refer to the
+  //     same Java mirror. The verifier will see the "one true mirror"
+  //     for the class being verified.
+  // 2. What is done at verification:
+  //   When the verifier makes calls into the VM to ask questions about
+  //   the class being verified, it will pass the jclass to JVM_* functions.
+  //   The jclass is always pointing to the mirror of _the_class.
+  //   ~28 JVM_* functions called by the verifier for the information
+  //   about CP entries and klass structure should check the jvmtiThreadState
+  //   info about equivalent klass versions and use it to replace a Klass*
+  //   of _the_class with a Klass* of _scratch_class. The function
+  //   class_to_verify_considering_redefinition() must be called for it.
+  //
+  //   Note again, that this redirection happens only for the verifier thread.
+  //   Other threads have very small overhead by checking the existence
+  //   of the jvmtiThreadSate and the information about klasses equivalence.
+  //   No JNI functions need to be changed, they don't reference the klass guts.
+  //   The JavaThread pointer is already available in all JVM_* functions
+  //   used by the verifier, so there is no extra performance issue with it.
+
+ private:
+  Klass* _the_class_for_redefinition_verification;
+  Klass* _scratch_class_for_redefinition_verification;
+
+ public:
+  inline void set_class_versions_map(Klass* the_class,
+                                     Klass* scratch_class) {
+    _the_class_for_redefinition_verification = the_class;
+    _scratch_class_for_redefinition_verification = scratch_class;
+  }
+
+  inline void clear_class_versions_map() { set_class_versions_map(NULL, NULL); }
+
+  static inline
+  Klass* class_to_verify_considering_redefinition(Klass* klass,
+                                                    JavaThread *thread) {
+    JvmtiThreadState *state = thread->jvmti_thread_state();
+    if (state != NULL && state->_the_class_for_redefinition_verification != NULL) {
+      if (state->_the_class_for_redefinition_verification == klass) {
+        klass = state->_scratch_class_for_redefinition_verification;
+      }
+    }
+    return klass;
+  }
+
+  // Todo: get rid of this!
+ private:
+  bool _debuggable;
+ public:
+  // Should the thread be enumerated by jvmtiInternal::GetAllThreads?
+  bool is_debuggable()                 { return _debuggable; }
+  // If a thread cannot be suspended (has no valid last_java_frame) then it gets marked !debuggable
+  void set_debuggable(bool debuggable) { _debuggable = debuggable; }
+
+ public:
+
+  bool may_be_walked();
+
+  // Thread local event collector setter and getter methods.
+  JvmtiDynamicCodeEventCollector* get_dynamic_code_event_collector() {
+    return _dynamic_code_event_collector;
+  }
+  JvmtiVMObjectAllocEventCollector* get_vm_object_alloc_event_collector() {
+    return _vm_object_alloc_event_collector;
+  }
+  void set_dynamic_code_event_collector(JvmtiDynamicCodeEventCollector* collector) {
+    _dynamic_code_event_collector = collector;
+  }
+  void set_vm_object_alloc_event_collector(JvmtiVMObjectAllocEventCollector* collector) {
+    _vm_object_alloc_event_collector = collector;
+  }
+
+
+  //
+  // Frame routines
+  //
+
+ public:
+
+  //  true when the thread was suspended with a pointer to the last Java frame.
+  bool has_last_frame()                     { return _thread->has_last_Java_frame(); }
+
+  void update_for_pop_top_frame();
+
+  // already holding JvmtiThreadState_lock - retrieve or create JvmtiThreadState
+  // Can return NULL if JavaThread is exiting.
+  inline static JvmtiThreadState *state_for_while_locked(JavaThread *thread) {
+    assert(JvmtiThreadState_lock->is_locked(), "sanity check");
+
+    JvmtiThreadState *state = thread->jvmti_thread_state();
+    if (state == NULL) {
+      if (thread->is_exiting()) {
+        // don't add a JvmtiThreadState to a thread that is exiting
+        return NULL;
+      }
+
+      state = new JvmtiThreadState(thread);
+    }
+    return state;
+  }
+
+  // retrieve or create JvmtiThreadState
+  // Can return NULL if JavaThread is exiting.
+  inline static JvmtiThreadState *state_for(JavaThread *thread) {
+    JvmtiThreadState *state = thread->jvmti_thread_state();
+    if (state == NULL) {
+      MutexLocker mu(JvmtiThreadState_lock);
+      // check again with the lock held
+      state = state_for_while_locked(thread);
+    } else {
+      CHECK_UNHANDLED_OOPS_ONLY(Thread::current()->clear_unhandled_oops());
+    }
+    return state;
+  }
+
+  // JVMTI ForceEarlyReturn support
+
+  // This is set to earlyret_pending to signal that top Java frame
+  // should be returned immediately
+ public:
+  int           _earlyret_state;
+  TosState      _earlyret_tos;
+  jvalue        _earlyret_value;
+  oop           _earlyret_oop;         // Used to return an oop result into Java code from
+                                       // ForceEarlyReturnObject, GC-preserved
+
+  // Setting and clearing earlyret_state
+  // earlyret_pending indicates that a ForceEarlyReturn() has been
+  // requested and not yet been completed.
+ public:
+  enum EarlyretState {
+    earlyret_inactive = 0,
+    earlyret_pending  = 1
+  };
+
+  void set_earlyret_pending(void) { _earlyret_state = earlyret_pending;  }
+  void clr_earlyret_pending(void) { _earlyret_state = earlyret_inactive; }
+  bool is_earlyret_pending(void)  { return (_earlyret_state == earlyret_pending);  }
+
+  TosState earlyret_tos()                            { return _earlyret_tos; }
+  oop  earlyret_oop() const                          { return _earlyret_oop; }
+  void set_earlyret_oop (oop x)                      { _earlyret_oop = x;    }
+  jvalue earlyret_value()                            { return _earlyret_value; }
+  void set_earlyret_value(jvalue val, TosState tos)  { _earlyret_tos = tos;  _earlyret_value = val;  }
+  void clr_earlyret_value()                          { _earlyret_tos = ilgl; _earlyret_value.j = 0L; }
+
+  static ByteSize earlyret_state_offset() { return byte_offset_of(JvmtiThreadState, _earlyret_state); }
+  static ByteSize earlyret_tos_offset()   { return byte_offset_of(JvmtiThreadState, _earlyret_tos); }
+  static ByteSize earlyret_oop_offset()   { return byte_offset_of(JvmtiThreadState, _earlyret_oop); }
+  static ByteSize earlyret_value_offset() { return byte_offset_of(JvmtiThreadState, _earlyret_value); }
+
+  void oops_do(OopClosure* f) NOT_JVMTI_RETURN; // GC support
+
+public:
+  void set_should_post_on_exceptions(bool val) { _thread->set_should_post_on_exceptions_flag(val ? JNI_TRUE : JNI_FALSE); }
+};
+
+class RedefineVerifyMark : public StackObj {
+ private:
+  JvmtiThreadState* _state;
+  Klass*            _scratch_class;
+  Handle            _scratch_mirror;
+
+ public:
+  RedefineVerifyMark(Klass* the_class, Klass* scratch_class,
+                     JvmtiThreadState *state) : _state(state), _scratch_class(scratch_class)
+  {
+    _state->set_class_versions_map(the_class, scratch_class);
+    _scratch_mirror = Handle(Thread::current(), _scratch_class->java_mirror());
+    _scratch_class->set_java_mirror(the_class->java_mirror());
+  }
+
+  ~RedefineVerifyMark() {
+    // Restore the scratch class's mirror, so when scratch_class is removed
+    // the correct mirror pointing to it can be cleared.
+    _scratch_class->set_java_mirror(_scratch_mirror());
+    _state->clear_class_versions_map();
+  }
+};
+
+#endif // SHARE_VM_PRIMS_JVMTITHREADSTATE_HPP