Mercurial > jdk8-mips64-public > hotspot / file revision

 /*

  * Copyright (c) 2003, 2012, 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.

  *

  */

 #include "precompiled.hpp"

 #include "jvmtifiles/jvmtiEnv.hpp"

 #include "memory/gcLocker.hpp"

 #include "memory/resourceArea.hpp"

 #include "prims/jvmtiEventController.inline.hpp"

 #include "prims/jvmtiImpl.hpp"

 #include "prims/jvmtiThreadState.inline.hpp"

 #include "runtime/vframe.hpp"

 // marker for when the stack depth has been reset and is now unknown.

 // any negative number would work but small ones might obscure an

 // underrun error.

 static const int UNKNOWN_STACK_DEPTH = -99;

 ///////////////////////////////////////////////////////////////

 //

 // class JvmtiThreadState

 //

 // Instances of JvmtiThreadState hang off of each thread.

 // Thread local storage for JVMTI.

 //

 JvmtiThreadState *JvmtiThreadState::_head = NULL;

 JvmtiThreadState::JvmtiThreadState(JavaThread* thread)

   : _thread_event_enable() {

   assert(JvmtiThreadState_lock->is_locked(), "sanity check");

   _thread               = thread;

   _exception_detected   = false;

   _exception_caught     = false;

   _debuggable           = true;

   _hide_single_stepping = false;

   _hide_level           = 0;

   _pending_step_for_popframe = false;

   _class_being_redefined = NULL;

   _class_load_kind = jvmti_class_load_kind_load;

   _head_env_thread_state = NULL;

   _dynamic_code_event_collector = NULL;

   _vm_object_alloc_event_collector = NULL;

   _the_class_for_redefinition_verification = NULL;

   _scratch_class_for_redefinition_verification = NULL;

   // JVMTI ForceEarlyReturn support

   _pending_step_for_earlyret = false;

   _earlyret_state = earlyret_inactive;

   _earlyret_tos = ilgl;

   _earlyret_value.j = 0L;

   _earlyret_oop = NULL;

   // add all the JvmtiEnvThreadState to the new JvmtiThreadState

   {

     JvmtiEnvIterator it;

     for (JvmtiEnvBase* env = it.first(); env != NULL; env = it.next(env)) {

       if (env->is_valid()) {

         add_env(env);

       }

     }

   }

   // link us into the list

   {

     // The thread state list manipulation code must not have safepoints.

     // See periodic_clean_up().

     debug_only(No_Safepoint_Verifier nosafepoint;)

     _prev = NULL;

     _next = _head;

     if (_head != NULL) {

       _head->_prev = this;

     }

     _head = this;

   }

   // set this as the state for the thread

   thread->set_jvmti_thread_state(this);

 }

 JvmtiThreadState::~JvmtiThreadState()   {

   assert(JvmtiThreadState_lock->is_locked(), "sanity check");

   // clear this as the state for the thread

   get_thread()->set_jvmti_thread_state(NULL);

   // zap our env thread states

   {

     JvmtiEnvBase::entering_dying_thread_env_iteration();

     JvmtiEnvThreadStateIterator it(this);

     for (JvmtiEnvThreadState* ets = it.first(); ets != NULL; ) {

       JvmtiEnvThreadState* zap = ets;

       ets = it.next(ets);

       delete zap;

     }

     JvmtiEnvBase::leaving_dying_thread_env_iteration();

   }

   // remove us from the list

   {

     // The thread state list manipulation code must not have safepoints.

     // See periodic_clean_up().

     debug_only(No_Safepoint_Verifier nosafepoint;)

     if (_prev == NULL) {

       assert(_head == this, "sanity check");

       _head = _next;

     } else {

       assert(_head != this, "sanity check");

       _prev->_next = _next;

     }

     if (_next != NULL) {

       _next->_prev = _prev;

     }

     _next = NULL;

     _prev = NULL;

   }

 }

 void

 JvmtiThreadState::periodic_clean_up() {

   assert(SafepointSynchronize::is_at_safepoint(), "at safepoint");

   // This iteration is initialized with "_head" instead of "JvmtiThreadState::first()"

   // because the latter requires the JvmtiThreadState_lock.

   // This iteration is safe at a safepoint as well, see the No_Safepoint_Verifier

   // asserts at all list manipulation sites.

   for (JvmtiThreadState *state = _head; state != NULL; state = state->next()) {

     // For each environment thread state corresponding to an invalid environment

     // unlink it from the list and deallocate it.

     JvmtiEnvThreadStateIterator it(state);

     JvmtiEnvThreadState* previous_ets = NULL;

     JvmtiEnvThreadState* ets = it.first();

     while (ets != NULL) {

       if (ets->get_env()->is_valid()) {

         previous_ets = ets;

         ets = it.next(ets);

       } else {

         // This one isn't valid, remove it from the list and deallocate it

         JvmtiEnvThreadState* defunct_ets = ets;

         ets = ets->next();

         if (previous_ets == NULL) {

           assert(state->head_env_thread_state() == defunct_ets, "sanity check");

           state->set_head_env_thread_state(ets);

         } else {

           previous_ets->set_next(ets);

         }

         delete defunct_ets;

       }

     }

   }

 }

 void JvmtiThreadState::add_env(JvmtiEnvBase *env) {

   assert(JvmtiThreadState_lock->is_locked(), "sanity check");

   JvmtiEnvThreadState *new_ets = new JvmtiEnvThreadState(_thread, env);

   // add this environment thread state to the end of the list (order is important)

   {

     // list deallocation (which occurs at a safepoint) cannot occur simultaneously

     debug_only(No_Safepoint_Verifier nosafepoint;)

     JvmtiEnvThreadStateIterator it(this);

     JvmtiEnvThreadState* previous_ets = NULL;

     for (JvmtiEnvThreadState* ets = it.first(); ets != NULL; ets = it.next(ets)) {

       previous_ets = ets;

     }

     if (previous_ets == NULL) {

       set_head_env_thread_state(new_ets);

     } else {

       previous_ets->set_next(new_ets);

     }

   }

 }

 void JvmtiThreadState::enter_interp_only_mode() {

   assert(_thread->get_interp_only_mode() == 0, "entering interp only when mode not zero");

   _thread->increment_interp_only_mode();

 }

 void JvmtiThreadState::leave_interp_only_mode() {

   assert(_thread->get_interp_only_mode() == 1, "leaving interp only when mode not one");

   _thread->decrement_interp_only_mode();

 }

 // Helper routine used in several places

 int JvmtiThreadState::count_frames() {

 #ifdef ASSERT

   uint32_t debug_bits = 0;

 #endif

   assert(SafepointSynchronize::is_at_safepoint() ||

          JvmtiEnv::is_thread_fully_suspended(get_thread(), false, &debug_bits),

          "at safepoint or must be suspended");

   if (!get_thread()->has_last_Java_frame()) return 0;  // no Java frames

   ResourceMark rm;

   RegisterMap reg_map(get_thread());

   javaVFrame *jvf = get_thread()->last_java_vframe(&reg_map);

   int n = 0;

   // tty->print_cr("CSD: counting frames on %s ...",

   //               JvmtiTrace::safe_get_thread_name(get_thread()));

   while (jvf != NULL) {

     Method* method = jvf->method();

     // tty->print_cr("CSD: frame - method %s.%s - loc %d",

     //               method->klass_name()->as_C_string(),

     //               method->name()->as_C_string(),

     //               jvf->bci() );

     jvf = jvf->java_sender();

     n++;

   }

   // tty->print_cr("CSD: frame count: %d", n);

   return n;

 }

 void JvmtiThreadState::invalidate_cur_stack_depth() {

   Thread *cur = Thread::current();

   uint32_t debug_bits = 0;

   // The caller can be the VMThread at a safepoint, the current thread

   // or the target thread must be suspended.

   guarantee((cur->is_VM_thread() && SafepointSynchronize::is_at_safepoint()) ||

     (JavaThread *)cur == get_thread() ||

     JvmtiEnv::is_thread_fully_suspended(get_thread(), false, &debug_bits),

     "sanity check");

   _cur_stack_depth = UNKNOWN_STACK_DEPTH;

 }

 void JvmtiThreadState::incr_cur_stack_depth() {

   guarantee(JavaThread::current() == get_thread(), "must be current thread");

   if (!is_interp_only_mode()) {

     _cur_stack_depth = UNKNOWN_STACK_DEPTH;

   }

   if (_cur_stack_depth != UNKNOWN_STACK_DEPTH) {

     ++_cur_stack_depth;

   }

 }

 void JvmtiThreadState::decr_cur_stack_depth() {

   guarantee(JavaThread::current() == get_thread(), "must be current thread");

   if (!is_interp_only_mode()) {

     _cur_stack_depth = UNKNOWN_STACK_DEPTH;

   }

   if (_cur_stack_depth != UNKNOWN_STACK_DEPTH) {

     --_cur_stack_depth;

     assert(_cur_stack_depth >= 0, "incr/decr_cur_stack_depth mismatch");

   }

 }

 int JvmtiThreadState::cur_stack_depth() {

   uint32_t debug_bits = 0;

   guarantee(JavaThread::current() == get_thread() ||

     JvmtiEnv::is_thread_fully_suspended(get_thread(), false, &debug_bits),

     "must be current thread or suspended");

   if (!is_interp_only_mode() || _cur_stack_depth == UNKNOWN_STACK_DEPTH) {

     _cur_stack_depth = count_frames();

   } else {

     // heavy weight assert

     assert(_cur_stack_depth == count_frames(),

            "cur_stack_depth out of sync");

   }

   return _cur_stack_depth;

 }

 bool JvmtiThreadState::may_be_walked() {

   return (get_thread()->is_being_ext_suspended() || (JavaThread::current() == get_thread()));

 }

 void JvmtiThreadState::process_pending_step_for_popframe() {

   // We are single stepping as the last part of the PopFrame() dance

   // so we have some house keeping to do.

   JavaThread *thr = get_thread();

   if (thr->popframe_condition() != JavaThread::popframe_inactive) {

     // If the popframe_condition field is not popframe_inactive, then

     // we missed all of the popframe_field cleanup points:

     //

     // - unpack_frames() was not called (nothing to deopt)

     // - remove_activation_preserving_args_entry() was not called

     //   (did not get suspended in a call_vm() family call and did

     //   not complete a call_vm() family call on the way here)

     thr->clear_popframe_condition();

   }

   // clearing the flag indicates we are done with the PopFrame() dance

   clr_pending_step_for_popframe();

   // If exception was thrown in this frame, need to reset jvmti thread state.

   // Single stepping may not get enabled correctly by the agent since

   // exception state is passed in MethodExit event which may be sent at some

   // time in the future. JDWP agent ignores MethodExit events if caused by

   // an exception.

   //

   if (is_exception_detected()) {

     clear_exception_detected();

   }

   // If step is pending for popframe then it may not be

   // a repeat step. The new_bci and method_id is same as current_bci

   // and current method_id after pop and step for recursive calls.

   // Force the step by clearing the last location.

   JvmtiEnvThreadStateIterator it(this);

   for (JvmtiEnvThreadState* ets = it.first(); ets != NULL; ets = it.next(ets)) {

     ets->clear_current_location();

   }

 }

 // Class:     JvmtiThreadState

 // Function:  update_for_pop_top_frame

 // Description:

 //   This function removes any frame pop notification request for

 //   the top frame and invalidates both the current stack depth and

 //   all cached frameIDs.

 //

 // Called by: PopFrame

 //

 void JvmtiThreadState::update_for_pop_top_frame() {

   if (is_interp_only_mode()) {

     // remove any frame pop notification request for the top frame

     // in any environment

     int popframe_number = cur_stack_depth();

     {

       JvmtiEnvThreadStateIterator it(this);

       for (JvmtiEnvThreadState* ets = it.first(); ets != NULL; ets = it.next(ets)) {

         if (ets->is_frame_pop(popframe_number)) {

           ets->clear_frame_pop(popframe_number);

         }

       }

     }

     // force stack depth to be recalculated

     invalidate_cur_stack_depth();

   } else {

     assert(!is_enabled(JVMTI_EVENT_FRAME_POP), "Must have no framepops set");

   }

 }

 void JvmtiThreadState::process_pending_step_for_earlyret() {

   // We are single stepping as the last part of the ForceEarlyReturn

   // dance so we have some house keeping to do.

   if (is_earlyret_pending()) {

     // If the earlyret_state field is not earlyret_inactive, then

     // we missed all of the earlyret_field cleanup points:

     //

     // - remove_activation() was not called

     //   (did not get suspended in a call_vm() family call and did

     //   not complete a call_vm() family call on the way here)

     //

     // One legitimate way for us to miss all the cleanup points is

     // if we got here right after handling a compiled return. If that

     // is the case, then we consider our return from compiled code to

     // complete the ForceEarlyReturn request and we clear the condition.

     clr_earlyret_pending();

     set_earlyret_oop(NULL);

     clr_earlyret_value();

   }

   // clearing the flag indicates we are done with

   // the ForceEarlyReturn() dance

   clr_pending_step_for_earlyret();

   // If exception was thrown in this frame, need to reset jvmti thread state.

   // Single stepping may not get enabled correctly by the agent since

   // exception state is passed in MethodExit event which may be sent at some

   // time in the future. JDWP agent ignores MethodExit events if caused by

   // an exception.

   //

   if (is_exception_detected()) {

     clear_exception_detected();

   }

   // If step is pending for earlyret then it may not be a repeat step.

   // The new_bci and method_id is same as current_bci and current

   // method_id after earlyret and step for recursive calls.

   // Force the step by clearing the last location.

   JvmtiEnvThreadStateIterator it(this);

   for (JvmtiEnvThreadState* ets = it.first(); ets != NULL; ets = it.next(ets)) {

     ets->clear_current_location();

   }

 }

 void JvmtiThreadState::oops_do(OopClosure* f) {

   f->do_oop((oop*) &_earlyret_oop);

 }