aoqi@0: /*
aoqi@0:  * Copyright (c) 2003, 2013, Oracle and/or its affiliates. All rights reserved.
aoqi@0:  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
aoqi@0:  *
aoqi@0:  * This code is free software; you can redistribute it and/or modify it
aoqi@0:  * under the terms of the GNU General Public License version 2 only, as
aoqi@0:  * published by the Free Software Foundation.
aoqi@0:  *
aoqi@0:  * This code is distributed in the hope that it will be useful, but WITHOUT
aoqi@0:  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
aoqi@0:  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
aoqi@0:  * version 2 for more details (a copy is included in the LICENSE file that
aoqi@0:  * accompanied this code).
aoqi@0:  *
aoqi@0:  * You should have received a copy of the GNU General Public License version
aoqi@0:  * 2 along with this work; if not, write to the Free Software Foundation,
aoqi@0:  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
aoqi@0:  *
aoqi@0:  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
aoqi@0:  * or visit www.oracle.com if you need additional information or have any
aoqi@0:  * questions.
aoqi@0:  *
aoqi@0:  */
aoqi@0: 
aoqi@0: #include "precompiled.hpp"
aoqi@0: #include "classfile/systemDictionary.hpp"
aoqi@0: #include "jvmtifiles/jvmtiEnv.hpp"
aoqi@0: #include "oops/objArrayKlass.hpp"
aoqi@0: #include "oops/objArrayOop.hpp"
aoqi@0: #include "prims/jvmtiEnvBase.hpp"
aoqi@0: #include "prims/jvmtiEventController.inline.hpp"
aoqi@0: #include "prims/jvmtiExtensions.hpp"
aoqi@0: #include "prims/jvmtiImpl.hpp"
aoqi@0: #include "prims/jvmtiManageCapabilities.hpp"
aoqi@0: #include "prims/jvmtiTagMap.hpp"
aoqi@0: #include "prims/jvmtiThreadState.inline.hpp"
aoqi@0: #include "runtime/biasedLocking.hpp"
aoqi@0: #include "runtime/deoptimization.hpp"
aoqi@0: #include "runtime/interfaceSupport.hpp"
aoqi@0: #include "runtime/jfieldIDWorkaround.hpp"
aoqi@0: #include "runtime/objectMonitor.hpp"
aoqi@0: #include "runtime/objectMonitor.inline.hpp"
aoqi@0: #include "runtime/signature.hpp"
aoqi@0: #include "runtime/vframe.hpp"
aoqi@0: #include "runtime/vframe_hp.hpp"
aoqi@0: #include "runtime/vmThread.hpp"
aoqi@0: #include "runtime/vm_operations.hpp"
aoqi@0: 
aoqi@0: ///////////////////////////////////////////////////////////////
aoqi@0: //
aoqi@0: // JvmtiEnvBase
aoqi@0: //
aoqi@0: 
aoqi@0: JvmtiEnvBase* JvmtiEnvBase::_head_environment = NULL;
aoqi@0: 
aoqi@0: bool JvmtiEnvBase::_globally_initialized = false;
aoqi@0: volatile bool JvmtiEnvBase::_needs_clean_up = false;
aoqi@0: 
aoqi@0: jvmtiPhase JvmtiEnvBase::_phase = JVMTI_PHASE_PRIMORDIAL;
aoqi@0: 
aoqi@0: volatile int JvmtiEnvBase::_dying_thread_env_iteration_count = 0;
aoqi@0: 
aoqi@0: extern jvmtiInterface_1_ jvmti_Interface;
aoqi@0: extern jvmtiInterface_1_ jvmtiTrace_Interface;
aoqi@0: 
aoqi@0: 
aoqi@0: // perform initializations that must occur before any JVMTI environments
aoqi@0: // are released but which should only be initialized once (no matter
aoqi@0: // how many environments are created).
aoqi@0: void
aoqi@0: JvmtiEnvBase::globally_initialize() {
aoqi@0:   assert(Threads::number_of_threads() == 0 || JvmtiThreadState_lock->is_locked(), "sanity check");
aoqi@0:   assert(_globally_initialized == false, "bad call");
aoqi@0: 
aoqi@0:   JvmtiManageCapabilities::initialize();
aoqi@0: 
aoqi@0:   // register extension functions and events
aoqi@0:   JvmtiExtensions::register_extensions();
aoqi@0: 
aoqi@0: #ifdef JVMTI_TRACE
aoqi@0:   JvmtiTrace::initialize();
aoqi@0: #endif
aoqi@0: 
aoqi@0:   _globally_initialized = true;
aoqi@0: }
aoqi@0: 
aoqi@0: 
aoqi@0: void
aoqi@0: JvmtiEnvBase::initialize() {
aoqi@0:   assert(Threads::number_of_threads() == 0 || JvmtiThreadState_lock->is_locked(), "sanity check");
aoqi@0: 
aoqi@0:   // Add this environment to the end of the environment list (order is important)
aoqi@0:   {
aoqi@0:     // This block of code must not contain any safepoints, as list deallocation
aoqi@0:     // (which occurs at a safepoint) cannot occur simultaneously with this list
aoqi@0:     // addition.  Note: No_Safepoint_Verifier cannot, currently, be used before
aoqi@0:     // threads exist.
aoqi@0:     JvmtiEnvIterator it;
aoqi@0:     JvmtiEnvBase *previous_env = NULL;
aoqi@0:     for (JvmtiEnvBase* env = it.first(); env != NULL; env = it.next(env)) {
aoqi@0:       previous_env = env;
aoqi@0:     }
aoqi@0:     if (previous_env == NULL) {
aoqi@0:       _head_environment = this;
aoqi@0:     } else {
aoqi@0:       previous_env->set_next_environment(this);
aoqi@0:     }
aoqi@0:   }
aoqi@0: 
aoqi@0:   if (_globally_initialized == false) {
aoqi@0:     globally_initialize();
aoqi@0:   }
aoqi@0: }
aoqi@0: 
aoqi@0: 
aoqi@0: bool
aoqi@0: JvmtiEnvBase::is_valid() {
aoqi@0:   jint value = 0;
aoqi@0: 
aoqi@0:   // This object might not be a JvmtiEnvBase so we can't assume
aoqi@0:   // the _magic field is properly aligned. Get the value in a safe
aoqi@0:   // way and then check against JVMTI_MAGIC.
aoqi@0: 
aoqi@0:   switch (sizeof(_magic)) {
aoqi@0:   case 2:
aoqi@0:     value = Bytes::get_native_u2((address)&_magic);
aoqi@0:     break;
aoqi@0: 
aoqi@0:   case 4:
aoqi@0:     value = Bytes::get_native_u4((address)&_magic);
aoqi@0:     break;
aoqi@0: 
aoqi@0:   case 8:
aoqi@0:     value = Bytes::get_native_u8((address)&_magic);
aoqi@0:     break;
aoqi@0: 
aoqi@0:   default:
aoqi@0:     guarantee(false, "_magic field is an unexpected size");
aoqi@0:   }
aoqi@0: 
aoqi@0:   return value == JVMTI_MAGIC;
aoqi@0: }
aoqi@0: 
aoqi@0: 
aoqi@0: bool
aoqi@0: JvmtiEnvBase::use_version_1_0_semantics() {
aoqi@0:   int major, minor, micro;
aoqi@0: 
aoqi@0:   JvmtiExport::decode_version_values(_version, &major, &minor, &micro);
aoqi@0:   return major == 1 && minor == 0;  // micro version doesn't matter here
aoqi@0: }
aoqi@0: 
aoqi@0: 
aoqi@0: bool
aoqi@0: JvmtiEnvBase::use_version_1_1_semantics() {
aoqi@0:   int major, minor, micro;
aoqi@0: 
aoqi@0:   JvmtiExport::decode_version_values(_version, &major, &minor, &micro);
aoqi@0:   return major == 1 && minor == 1;  // micro version doesn't matter here
aoqi@0: }
aoqi@0: 
aoqi@0: bool
aoqi@0: JvmtiEnvBase::use_version_1_2_semantics() {
aoqi@0:   int major, minor, micro;
aoqi@0: 
aoqi@0:   JvmtiExport::decode_version_values(_version, &major, &minor, &micro);
aoqi@0:   return major == 1 && minor == 2;  // micro version doesn't matter here
aoqi@0: }
aoqi@0: 
aoqi@0: 
aoqi@0: JvmtiEnvBase::JvmtiEnvBase(jint version) : _env_event_enable() {
aoqi@0:   _version = version;
aoqi@0:   _env_local_storage = NULL;
aoqi@0:   _tag_map = NULL;
aoqi@0:   _native_method_prefix_count = 0;
aoqi@0:   _native_method_prefixes = NULL;
aoqi@0:   _next = NULL;
aoqi@0:   _class_file_load_hook_ever_enabled = false;
aoqi@0: 
aoqi@0:   // Moot since ClassFileLoadHook not yet enabled.
aoqi@0:   // But "true" will give a more predictable ClassFileLoadHook behavior
aoqi@0:   // for environment creation during ClassFileLoadHook.
aoqi@0:   _is_retransformable = true;
aoqi@0: 
aoqi@0:   // all callbacks initially NULL
aoqi@0:   memset(&_event_callbacks,0,sizeof(jvmtiEventCallbacks));
aoqi@0: 
aoqi@0:   // all capabilities initially off
aoqi@0:   memset(&_current_capabilities, 0, sizeof(_current_capabilities));
aoqi@0: 
aoqi@0:   // all prohibited capabilities initially off
aoqi@0:   memset(&_prohibited_capabilities, 0, sizeof(_prohibited_capabilities));
aoqi@0: 
aoqi@0:   _magic = JVMTI_MAGIC;
aoqi@0: 
aoqi@0:   JvmtiEventController::env_initialize((JvmtiEnv*)this);
aoqi@0: 
aoqi@0: #ifdef JVMTI_TRACE
aoqi@0:   _jvmti_external.functions = TraceJVMTI != NULL ? &jvmtiTrace_Interface : &jvmti_Interface;
aoqi@0: #else
aoqi@0:   _jvmti_external.functions = &jvmti_Interface;
aoqi@0: #endif
aoqi@0: }
aoqi@0: 
aoqi@0: 
aoqi@0: void
aoqi@0: JvmtiEnvBase::dispose() {
aoqi@0: 
aoqi@0: #ifdef JVMTI_TRACE
aoqi@0:   JvmtiTrace::shutdown();
aoqi@0: #endif
aoqi@0: 
aoqi@0:   // Dispose of event info and let the event controller call us back
aoqi@0:   // in a locked state (env_dispose, below)
aoqi@0:   JvmtiEventController::env_dispose(this);
aoqi@0: }
aoqi@0: 
aoqi@0: void
aoqi@0: JvmtiEnvBase::env_dispose() {
aoqi@0:   assert(Threads::number_of_threads() == 0 || JvmtiThreadState_lock->is_locked(), "sanity check");
aoqi@0: 
aoqi@0:   // We have been entered with all events disabled on this environment.
aoqi@0:   // A race to re-enable events (by setting callbacks) is prevented by
aoqi@0:   // checking for a valid environment when setting callbacks (while
aoqi@0:   // holding the JvmtiThreadState_lock).
aoqi@0: 
aoqi@0:   // Mark as invalid.
aoqi@0:   _magic = DISPOSED_MAGIC;
aoqi@0: 
aoqi@0:   // Relinquish all capabilities.
aoqi@0:   jvmtiCapabilities *caps = get_capabilities();
aoqi@0:   JvmtiManageCapabilities::relinquish_capabilities(caps, caps, caps);
aoqi@0: 
aoqi@0:   // Same situation as with events (see above)
aoqi@0:   set_native_method_prefixes(0, NULL);
aoqi@0: 
aoqi@0:   JvmtiTagMap* tag_map_to_deallocate = _tag_map;
aoqi@0:   set_tag_map(NULL);
aoqi@0:   // A tag map can be big, deallocate it now
aoqi@0:   if (tag_map_to_deallocate != NULL) {
aoqi@0:     delete tag_map_to_deallocate;
aoqi@0:   }
aoqi@0: 
aoqi@0:   _needs_clean_up = true;
aoqi@0: }
aoqi@0: 
aoqi@0: 
aoqi@0: JvmtiEnvBase::~JvmtiEnvBase() {
aoqi@0:   assert(SafepointSynchronize::is_at_safepoint(), "sanity check");
aoqi@0: 
aoqi@0:   // There is a small window of time during which the tag map of a
aoqi@0:   // disposed environment could have been reallocated.
aoqi@0:   // Make sure it is gone.
aoqi@0:   JvmtiTagMap* tag_map_to_deallocate = _tag_map;
aoqi@0:   set_tag_map(NULL);
aoqi@0:   // A tag map can be big, deallocate it now
aoqi@0:   if (tag_map_to_deallocate != NULL) {
aoqi@0:     delete tag_map_to_deallocate;
aoqi@0:   }
aoqi@0: 
aoqi@0:   _magic = BAD_MAGIC;
aoqi@0: }
aoqi@0: 
aoqi@0: 
aoqi@0: void
aoqi@0: JvmtiEnvBase::periodic_clean_up() {
aoqi@0:   assert(SafepointSynchronize::is_at_safepoint(), "sanity check");
aoqi@0: 
aoqi@0:   // JvmtiEnvBase reference is saved in JvmtiEnvThreadState. So
aoqi@0:   // clean up JvmtiThreadState before deleting JvmtiEnv pointer.
aoqi@0:   JvmtiThreadState::periodic_clean_up();
aoqi@0: 
aoqi@0:   // Unlink all invalid environments from the list of environments
aoqi@0:   // and deallocate them
aoqi@0:   JvmtiEnvIterator it;
aoqi@0:   JvmtiEnvBase* previous_env = NULL;
aoqi@0:   JvmtiEnvBase* env = it.first();
aoqi@0:   while (env != NULL) {
aoqi@0:     if (env->is_valid()) {
aoqi@0:       previous_env = env;
aoqi@0:       env = it.next(env);
aoqi@0:     } else {
aoqi@0:       // This one isn't valid, remove it from the list and deallocate it
aoqi@0:       JvmtiEnvBase* defunct_env = env;
aoqi@0:       env = it.next(env);
aoqi@0:       if (previous_env == NULL) {
aoqi@0:         _head_environment = env;
aoqi@0:       } else {
aoqi@0:         previous_env->set_next_environment(env);
aoqi@0:       }
aoqi@0:       delete defunct_env;
aoqi@0:     }
aoqi@0:   }
aoqi@0: 
aoqi@0: }
aoqi@0: 
aoqi@0: 
aoqi@0: void
aoqi@0: JvmtiEnvBase::check_for_periodic_clean_up() {
aoqi@0:   assert(SafepointSynchronize::is_at_safepoint(), "sanity check");
aoqi@0: 
aoqi@0:   class ThreadInsideIterationClosure: public ThreadClosure {
aoqi@0:    private:
aoqi@0:     bool _inside;
aoqi@0:    public:
aoqi@0:     ThreadInsideIterationClosure() : _inside(false) {};
aoqi@0: 
aoqi@0:     void do_thread(Thread* thread) {
aoqi@0:       _inside |= thread->is_inside_jvmti_env_iteration();
aoqi@0:     }
aoqi@0: 
aoqi@0:     bool is_inside_jvmti_env_iteration() {
aoqi@0:       return _inside;
aoqi@0:     }
aoqi@0:   };
aoqi@0: 
aoqi@0:   if (_needs_clean_up) {
aoqi@0:     // Check if we are currently iterating environment,
aoqi@0:     // deallocation should not occur if we are
aoqi@0:     ThreadInsideIterationClosure tiic;
aoqi@0:     Threads::threads_do(&tiic);
aoqi@0:     if (!tiic.is_inside_jvmti_env_iteration() &&
aoqi@0:              !is_inside_dying_thread_env_iteration()) {
aoqi@0:       _needs_clean_up = false;
aoqi@0:       JvmtiEnvBase::periodic_clean_up();
aoqi@0:     }
aoqi@0:   }
aoqi@0: }
aoqi@0: 
aoqi@0: 
aoqi@0: void
aoqi@0: JvmtiEnvBase::record_first_time_class_file_load_hook_enabled() {
aoqi@0:   assert(Threads::number_of_threads() == 0 || JvmtiThreadState_lock->is_locked(),
aoqi@0:          "sanity check");
aoqi@0: 
aoqi@0:   if (!_class_file_load_hook_ever_enabled) {
aoqi@0:     _class_file_load_hook_ever_enabled = true;
aoqi@0: 
aoqi@0:     if (get_capabilities()->can_retransform_classes) {
aoqi@0:       _is_retransformable = true;
aoqi@0:     } else {
aoqi@0:       _is_retransformable = false;
aoqi@0: 
aoqi@0:       // cannot add retransform capability after ClassFileLoadHook has been enabled
aoqi@0:       get_prohibited_capabilities()->can_retransform_classes = 1;
aoqi@0:     }
aoqi@0:   }
aoqi@0: }
aoqi@0: 
aoqi@0: 
aoqi@0: void
aoqi@0: JvmtiEnvBase::record_class_file_load_hook_enabled() {
aoqi@0:   if (!_class_file_load_hook_ever_enabled) {
aoqi@0:     if (Threads::number_of_threads() == 0) {
aoqi@0:       record_first_time_class_file_load_hook_enabled();
aoqi@0:     } else {
aoqi@0:       MutexLocker mu(JvmtiThreadState_lock);
aoqi@0:       record_first_time_class_file_load_hook_enabled();
aoqi@0:     }
aoqi@0:   }
aoqi@0: }
aoqi@0: 
aoqi@0: 
aoqi@0: jvmtiError
aoqi@0: JvmtiEnvBase::set_native_method_prefixes(jint prefix_count, char** prefixes) {
aoqi@0:   assert(Threads::number_of_threads() == 0 || JvmtiThreadState_lock->is_locked(),
aoqi@0:          "sanity check");
aoqi@0: 
aoqi@0:   int old_prefix_count = get_native_method_prefix_count();
aoqi@0:   char **old_prefixes = get_native_method_prefixes();
aoqi@0: 
aoqi@0:   // allocate and install the new prefixex
aoqi@0:   if (prefix_count == 0 || !is_valid()) {
aoqi@0:     _native_method_prefix_count = 0;
aoqi@0:     _native_method_prefixes = NULL;
aoqi@0:   } else {
aoqi@0:     // there are prefixes, allocate an array to hold them, and fill it
aoqi@0:     char** new_prefixes = (char**)os::malloc((prefix_count) * sizeof(char*), mtInternal);
aoqi@0:     if (new_prefixes == NULL) {
aoqi@0:       return JVMTI_ERROR_OUT_OF_MEMORY;
aoqi@0:     }
aoqi@0:     for (int i = 0; i < prefix_count; i++) {
aoqi@0:       char* prefix = prefixes[i];
aoqi@0:       if (prefix == NULL) {
aoqi@0:         for (int j = 0; j < (i-1); j++) {
aoqi@0:           os::free(new_prefixes[j]);
aoqi@0:         }
aoqi@0:         os::free(new_prefixes);
aoqi@0:         return JVMTI_ERROR_NULL_POINTER;
aoqi@0:       }
aoqi@0:       prefix = os::strdup(prefixes[i]);
aoqi@0:       if (prefix == NULL) {
aoqi@0:         for (int j = 0; j < (i-1); j++) {
aoqi@0:           os::free(new_prefixes[j]);
aoqi@0:         }
aoqi@0:         os::free(new_prefixes);
aoqi@0:         return JVMTI_ERROR_OUT_OF_MEMORY;
aoqi@0:       }
aoqi@0:       new_prefixes[i] = prefix;
aoqi@0:     }
aoqi@0:     _native_method_prefix_count = prefix_count;
aoqi@0:     _native_method_prefixes = new_prefixes;
aoqi@0:   }
aoqi@0: 
aoqi@0:   // now that we know the new prefixes have been successfully installed we can
aoqi@0:   // safely remove the old ones
aoqi@0:   if (old_prefix_count != 0) {
aoqi@0:     for (int i = 0; i < old_prefix_count; i++) {
aoqi@0:       os::free(old_prefixes[i]);
aoqi@0:     }
aoqi@0:     os::free(old_prefixes);
aoqi@0:   }
aoqi@0: 
aoqi@0:   return JVMTI_ERROR_NONE;
aoqi@0: }
aoqi@0: 
aoqi@0: 
aoqi@0: // Collect all the prefixes which have been set in any JVM TI environments
aoqi@0: // by the SetNativeMethodPrefix(es) functions.  Be sure to maintain the
aoqi@0: // order of environments and the order of prefixes within each environment.
aoqi@0: // Return in a resource allocated array.
aoqi@0: char**
aoqi@0: JvmtiEnvBase::get_all_native_method_prefixes(int* count_ptr) {
aoqi@0:   assert(Threads::number_of_threads() == 0 ||
aoqi@0:          SafepointSynchronize::is_at_safepoint() ||
aoqi@0:          JvmtiThreadState_lock->is_locked(),
aoqi@0:          "sanity check");
aoqi@0: 
aoqi@0:   int total_count = 0;
aoqi@0:   GrowableArray<char*>* prefix_array =new GrowableArray<char*>(5);
aoqi@0: 
aoqi@0:   JvmtiEnvIterator it;
aoqi@0:   for (JvmtiEnvBase* env = it.first(); env != NULL; env = it.next(env)) {
aoqi@0:     int prefix_count = env->get_native_method_prefix_count();
aoqi@0:     char** prefixes = env->get_native_method_prefixes();
aoqi@0:     for (int j = 0; j < prefix_count; j++) {
aoqi@0:       // retrieve a prefix and so that it is safe against asynchronous changes
aoqi@0:       // copy it into the resource area
aoqi@0:       char* prefix = prefixes[j];
aoqi@0:       char* prefix_copy = NEW_RESOURCE_ARRAY(char, strlen(prefix)+1);
aoqi@0:       strcpy(prefix_copy, prefix);
aoqi@0:       prefix_array->at_put_grow(total_count++, prefix_copy);
aoqi@0:     }
aoqi@0:   }
aoqi@0: 
aoqi@0:   char** all_prefixes = NEW_RESOURCE_ARRAY(char*, total_count);
aoqi@0:   char** p = all_prefixes;
aoqi@0:   for (int i = 0; i < total_count; ++i) {
aoqi@0:     *p++ = prefix_array->at(i);
aoqi@0:   }
aoqi@0:   *count_ptr = total_count;
aoqi@0:   return all_prefixes;
aoqi@0: }
aoqi@0: 
aoqi@0: void
aoqi@0: JvmtiEnvBase::set_event_callbacks(const jvmtiEventCallbacks* callbacks,
aoqi@0:                                                jint size_of_callbacks) {
aoqi@0:   assert(Threads::number_of_threads() == 0 || JvmtiThreadState_lock->is_locked(), "sanity check");
aoqi@0: 
aoqi@0:   size_t byte_cnt = sizeof(jvmtiEventCallbacks);
aoqi@0: 
aoqi@0:   // clear in either case to be sure we got any gap between sizes
aoqi@0:   memset(&_event_callbacks, 0, byte_cnt);
aoqi@0: 
aoqi@0:   // Now that JvmtiThreadState_lock is held, prevent a possible race condition where events
aoqi@0:   // are re-enabled by a call to set event callbacks where the DisposeEnvironment
aoqi@0:   // occurs after the boiler-plate environment check and before the lock is acquired.
aoqi@0:   if (callbacks != NULL && is_valid()) {
aoqi@0:     if (size_of_callbacks < (jint)byte_cnt) {
aoqi@0:       byte_cnt = size_of_callbacks;
aoqi@0:     }
aoqi@0:     memcpy(&_event_callbacks, callbacks, byte_cnt);
aoqi@0:   }
aoqi@0: }
aoqi@0: 
aoqi@0: // Called from JVMTI entry points which perform stack walking. If the
aoqi@0: // associated JavaThread is the current thread, then wait_for_suspend
aoqi@0: // is not used. Otherwise, it determines if we should wait for the
aoqi@0: // "other" thread to complete external suspension. (NOTE: in future
aoqi@0: // releases the suspension mechanism should be reimplemented so this
aoqi@0: // is not necessary.)
aoqi@0: //
aoqi@0: bool
aoqi@0: JvmtiEnvBase::is_thread_fully_suspended(JavaThread* thr, bool wait_for_suspend, uint32_t *bits) {
aoqi@0:   // "other" threads require special handling
aoqi@0:   if (thr != JavaThread::current()) {
aoqi@0:     if (wait_for_suspend) {
aoqi@0:       // We are allowed to wait for the external suspend to complete
aoqi@0:       // so give the other thread a chance to get suspended.
aoqi@0:       if (!thr->wait_for_ext_suspend_completion(SuspendRetryCount,
aoqi@0:           SuspendRetryDelay, bits)) {
aoqi@0:         // didn't make it so let the caller know
aoqi@0:         return false;
aoqi@0:       }
aoqi@0:     }
aoqi@0:     // We aren't allowed to wait for the external suspend to complete
aoqi@0:     // so if the other thread isn't externally suspended we need to
aoqi@0:     // let the caller know.
aoqi@0:     else if (!thr->is_ext_suspend_completed_with_lock(bits)) {
aoqi@0:       return false;
aoqi@0:     }
aoqi@0:   }
aoqi@0: 
aoqi@0:   return true;
aoqi@0: }
aoqi@0: 
aoqi@0: 
aoqi@0: // In the fullness of time, all users of the method should instead
aoqi@0: // directly use allocate, besides being cleaner and faster, this will
aoqi@0: // mean much better out of memory handling
aoqi@0: unsigned char *
aoqi@0: JvmtiEnvBase::jvmtiMalloc(jlong size) {
aoqi@0:   unsigned char* mem;
aoqi@0:   jvmtiError result = allocate(size, &mem);
aoqi@0:   assert(result == JVMTI_ERROR_NONE, "Allocate failed");
aoqi@0:   return mem;
aoqi@0: }
aoqi@0: 
aoqi@0: 
aoqi@0: //
aoqi@0: // Threads
aoqi@0: //
aoqi@0: 
aoqi@0: jobject *
aoqi@0: JvmtiEnvBase::new_jobjectArray(int length, Handle *handles) {
aoqi@0:   if (length == 0) {
aoqi@0:     return NULL;
aoqi@0:   }
aoqi@0: 
aoqi@0:   jobject *objArray = (jobject *) jvmtiMalloc(sizeof(jobject) * length);
aoqi@0:   NULL_CHECK(objArray, NULL);
aoqi@0: 
aoqi@0:   for (int i=0; i<length; i++) {
aoqi@0:     objArray[i] = jni_reference(handles[i]);
aoqi@0:   }
aoqi@0:   return objArray;
aoqi@0: }
aoqi@0: 
aoqi@0: jthread *
aoqi@0: JvmtiEnvBase::new_jthreadArray(int length, Handle *handles) {
aoqi@0:   return (jthread *) new_jobjectArray(length,handles);
aoqi@0: }
aoqi@0: 
aoqi@0: jthreadGroup *
aoqi@0: JvmtiEnvBase::new_jthreadGroupArray(int length, Handle *handles) {
aoqi@0:   return (jthreadGroup *) new_jobjectArray(length,handles);
aoqi@0: }
aoqi@0: 
aoqi@0: 
aoqi@0: JavaThread *
aoqi@0: JvmtiEnvBase::get_JavaThread(jthread jni_thread) {
aoqi@0:   oop t = JNIHandles::resolve_external_guard(jni_thread);
aoqi@0:   if (t == NULL || !t->is_a(SystemDictionary::Thread_klass())) {
aoqi@0:     return NULL;
aoqi@0:   }
aoqi@0:   // The following returns NULL if the thread has not yet run or is in
aoqi@0:   // process of exiting
aoqi@0:   return java_lang_Thread::thread(t);
aoqi@0: }
aoqi@0: 
aoqi@0: 
aoqi@0: // return the vframe on the specified thread and depth, NULL if no such frame
aoqi@0: vframe*
aoqi@0: JvmtiEnvBase::vframeFor(JavaThread* java_thread, jint depth) {
aoqi@0:   if (!java_thread->has_last_Java_frame()) {
aoqi@0:     return NULL;
aoqi@0:   }
aoqi@0:   RegisterMap reg_map(java_thread);
aoqi@0:   vframe *vf = java_thread->last_java_vframe(&reg_map);
aoqi@0:   int d = 0;
aoqi@0:   while ((vf != NULL) && (d < depth)) {
aoqi@0:     vf = vf->java_sender();
aoqi@0:     d++;
aoqi@0:   }
aoqi@0:   return vf;
aoqi@0: }
aoqi@0: 
aoqi@0: 
aoqi@0: //
aoqi@0: // utilities: JNI objects
aoqi@0: //
aoqi@0: 
aoqi@0: 
aoqi@0: jclass
aoqi@0: JvmtiEnvBase::get_jni_class_non_null(Klass* k) {
aoqi@0:   assert(k != NULL, "k != NULL");
aoqi@0:   return (jclass)jni_reference(k->java_mirror());
aoqi@0: }
aoqi@0: 
aoqi@0: //
aoqi@0: // Field Information
aoqi@0: //
aoqi@0: 
aoqi@0: bool
aoqi@0: JvmtiEnvBase::get_field_descriptor(Klass* k, jfieldID field, fieldDescriptor* fd) {
aoqi@0:   if (!jfieldIDWorkaround::is_valid_jfieldID(k, field)) {
aoqi@0:     return false;
aoqi@0:   }
aoqi@0:   bool found = false;
aoqi@0:   if (jfieldIDWorkaround::is_static_jfieldID(field)) {
aoqi@0:     JNIid* id = jfieldIDWorkaround::from_static_jfieldID(field);
aoqi@0:     found = id->find_local_field(fd);
aoqi@0:   } else {
aoqi@0:     // Non-static field. The fieldID is really the offset of the field within the object.
aoqi@0:     int offset = jfieldIDWorkaround::from_instance_jfieldID(k, field);
aoqi@0:     found = InstanceKlass::cast(k)->find_field_from_offset(offset, false, fd);
aoqi@0:   }
aoqi@0:   return found;
aoqi@0: }
aoqi@0: 
aoqi@0: //
aoqi@0: // Object Monitor Information
aoqi@0: //
aoqi@0: 
aoqi@0: //
aoqi@0: // Count the number of objects for a lightweight monitor. The hobj
aoqi@0: // parameter is object that owns the monitor so this routine will
aoqi@0: // count the number of times the same object was locked by frames
aoqi@0: // in java_thread.
aoqi@0: //
aoqi@0: jint
aoqi@0: JvmtiEnvBase::count_locked_objects(JavaThread *java_thread, Handle hobj) {
aoqi@0:   jint ret = 0;
aoqi@0:   if (!java_thread->has_last_Java_frame()) {
aoqi@0:     return ret;  // no Java frames so no monitors
aoqi@0:   }
aoqi@0: 
aoqi@0:   ResourceMark rm;
aoqi@0:   HandleMark   hm;
aoqi@0:   RegisterMap  reg_map(java_thread);
aoqi@0: 
aoqi@0:   for(javaVFrame *jvf=java_thread->last_java_vframe(&reg_map); jvf != NULL;
aoqi@0:                                                  jvf = jvf->java_sender()) {
aoqi@0:     GrowableArray<MonitorInfo*>* mons = jvf->monitors();
aoqi@0:     if (!mons->is_empty()) {
aoqi@0:       for (int i = 0; i < mons->length(); i++) {
aoqi@0:         MonitorInfo *mi = mons->at(i);
aoqi@0:         if (mi->owner_is_scalar_replaced()) continue;
aoqi@0: 
aoqi@0:         // see if owner of the monitor is our object
aoqi@0:         if (mi->owner() != NULL && mi->owner() == hobj()) {
aoqi@0:           ret++;
aoqi@0:         }
aoqi@0:       }
aoqi@0:     }
aoqi@0:   }
aoqi@0:   return ret;
aoqi@0: }
aoqi@0: 
aoqi@0: 
aoqi@0: 
aoqi@0: jvmtiError
aoqi@0: JvmtiEnvBase::get_current_contended_monitor(JavaThread *calling_thread, JavaThread *java_thread, jobject *monitor_ptr) {
aoqi@0: #ifdef ASSERT
aoqi@0:   uint32_t debug_bits = 0;
aoqi@0: #endif
aoqi@0:   assert((SafepointSynchronize::is_at_safepoint() ||
aoqi@0:           is_thread_fully_suspended(java_thread, false, &debug_bits)),
aoqi@0:          "at safepoint or target thread is suspended");
aoqi@0:   oop obj = NULL;
aoqi@0:   ObjectMonitor *mon = java_thread->current_waiting_monitor();
aoqi@0:   if (mon == NULL) {
aoqi@0:     // thread is not doing an Object.wait() call
aoqi@0:     mon = java_thread->current_pending_monitor();
aoqi@0:     if (mon != NULL) {
aoqi@0:       // The thread is trying to enter() or raw_enter() an ObjectMonitor.
aoqi@0:       obj = (oop)mon->object();
aoqi@0:       // If obj == NULL, then ObjectMonitor is raw which doesn't count
aoqi@0:       // as contended for this API
aoqi@0:     }
aoqi@0:     // implied else: no contended ObjectMonitor
aoqi@0:   } else {
aoqi@0:     // thread is doing an Object.wait() call
aoqi@0:     obj = (oop)mon->object();
aoqi@0:     assert(obj != NULL, "Object.wait() should have an object");
aoqi@0:   }
aoqi@0: 
aoqi@0:   if (obj == NULL) {
aoqi@0:     *monitor_ptr = NULL;
aoqi@0:   } else {
aoqi@0:     HandleMark hm;
aoqi@0:     Handle     hobj(obj);
aoqi@0:     *monitor_ptr = jni_reference(calling_thread, hobj);
aoqi@0:   }
aoqi@0:   return JVMTI_ERROR_NONE;
aoqi@0: }
aoqi@0: 
aoqi@0: 
aoqi@0: jvmtiError
aoqi@0: JvmtiEnvBase::get_owned_monitors(JavaThread *calling_thread, JavaThread* java_thread,
aoqi@0:                                  GrowableArray<jvmtiMonitorStackDepthInfo*> *owned_monitors_list) {
aoqi@0:   jvmtiError err = JVMTI_ERROR_NONE;
aoqi@0: #ifdef ASSERT
aoqi@0:   uint32_t debug_bits = 0;
aoqi@0: #endif
aoqi@0:   assert((SafepointSynchronize::is_at_safepoint() ||
aoqi@0:           is_thread_fully_suspended(java_thread, false, &debug_bits)),
aoqi@0:          "at safepoint or target thread is suspended");
aoqi@0: 
aoqi@0:   if (java_thread->has_last_Java_frame()) {
aoqi@0:     ResourceMark rm;
aoqi@0:     HandleMark   hm;
aoqi@0:     RegisterMap  reg_map(java_thread);
aoqi@0: 
aoqi@0:     int depth = 0;
aoqi@0:     for (javaVFrame *jvf = java_thread->last_java_vframe(&reg_map); jvf != NULL;
aoqi@0:          jvf = jvf->java_sender()) {
aoqi@0:       if (depth++ < MaxJavaStackTraceDepth) {  // check for stack too deep
aoqi@0:         // add locked objects for this frame into list
aoqi@0:         err = get_locked_objects_in_frame(calling_thread, java_thread, jvf, owned_monitors_list, depth-1);
aoqi@0:         if (err != JVMTI_ERROR_NONE) {
aoqi@0:           return err;
aoqi@0:         }
aoqi@0:       }
aoqi@0:     }
aoqi@0:   }
aoqi@0: 
aoqi@0:   // Get off stack monitors. (e.g. acquired via jni MonitorEnter).
aoqi@0:   JvmtiMonitorClosure jmc(java_thread, calling_thread, owned_monitors_list, this);
aoqi@0:   ObjectSynchronizer::monitors_iterate(&jmc);
aoqi@0:   err = jmc.error();
aoqi@0: 
aoqi@0:   return err;
aoqi@0: }
aoqi@0: 
aoqi@0: // Save JNI local handles for any objects that this frame owns.
aoqi@0: jvmtiError
aoqi@0: JvmtiEnvBase::get_locked_objects_in_frame(JavaThread* calling_thread, JavaThread* java_thread,
aoqi@0:                                  javaVFrame *jvf, GrowableArray<jvmtiMonitorStackDepthInfo*>* owned_monitors_list, int stack_depth) {
aoqi@0:   jvmtiError err = JVMTI_ERROR_NONE;
aoqi@0:   ResourceMark rm;
aoqi@0: 
aoqi@0:   GrowableArray<MonitorInfo*>* mons = jvf->monitors();
aoqi@0:   if (mons->is_empty()) {
aoqi@0:     return err;  // this javaVFrame holds no monitors
aoqi@0:   }
aoqi@0: 
aoqi@0:   HandleMark hm;
aoqi@0:   oop wait_obj = NULL;
aoqi@0:   {
aoqi@0:     // save object of current wait() call (if any) for later comparison
aoqi@0:     ObjectMonitor *mon = java_thread->current_waiting_monitor();
aoqi@0:     if (mon != NULL) {
aoqi@0:       wait_obj = (oop)mon->object();
aoqi@0:     }
aoqi@0:   }
aoqi@0:   oop pending_obj = NULL;
aoqi@0:   {
aoqi@0:     // save object of current enter() call (if any) for later comparison
aoqi@0:     ObjectMonitor *mon = java_thread->current_pending_monitor();
aoqi@0:     if (mon != NULL) {
aoqi@0:       pending_obj = (oop)mon->object();
aoqi@0:     }
aoqi@0:   }
aoqi@0: 
aoqi@0:   for (int i = 0; i < mons->length(); i++) {
aoqi@0:     MonitorInfo *mi = mons->at(i);
aoqi@0: 
aoqi@0:     if (mi->owner_is_scalar_replaced()) continue;
aoqi@0: 
aoqi@0:     oop obj = mi->owner();
aoqi@0:     if (obj == NULL) {
aoqi@0:       // this monitor doesn't have an owning object so skip it
aoqi@0:       continue;
aoqi@0:     }
aoqi@0: 
aoqi@0:     if (wait_obj == obj) {
aoqi@0:       // the thread is waiting on this monitor so it isn't really owned
aoqi@0:       continue;
aoqi@0:     }
aoqi@0: 
aoqi@0:     if (pending_obj == obj) {
aoqi@0:       // the thread is pending on this monitor so it isn't really owned
aoqi@0:       continue;
aoqi@0:     }
aoqi@0: 
aoqi@0:     if (owned_monitors_list->length() > 0) {
aoqi@0:       // Our list has at least one object on it so we have to check
aoqi@0:       // for recursive object locking
aoqi@0:       bool found = false;
aoqi@0:       for (int j = 0; j < owned_monitors_list->length(); j++) {
aoqi@0:         jobject jobj = ((jvmtiMonitorStackDepthInfo*)owned_monitors_list->at(j))->monitor;
aoqi@0:         oop check = JNIHandles::resolve(jobj);
aoqi@0:         if (check == obj) {
aoqi@0:           found = true;  // we found the object
aoqi@0:           break;
aoqi@0:         }
aoqi@0:       }
aoqi@0: 
aoqi@0:       if (found) {
aoqi@0:         // already have this object so don't include it
aoqi@0:         continue;
aoqi@0:       }
aoqi@0:     }
aoqi@0: 
aoqi@0:     // add the owning object to our list
aoqi@0:     jvmtiMonitorStackDepthInfo *jmsdi;
aoqi@0:     err = allocate(sizeof(jvmtiMonitorStackDepthInfo), (unsigned char **)&jmsdi);
aoqi@0:     if (err != JVMTI_ERROR_NONE) {
aoqi@0:         return err;
aoqi@0:     }
aoqi@0:     Handle hobj(obj);
aoqi@0:     jmsdi->monitor = jni_reference(calling_thread, hobj);
aoqi@0:     jmsdi->stack_depth = stack_depth;
aoqi@0:     owned_monitors_list->append(jmsdi);
aoqi@0:   }
aoqi@0: 
aoqi@0:   return err;
aoqi@0: }
aoqi@0: 
aoqi@0: jvmtiError
aoqi@0: JvmtiEnvBase::get_stack_trace(JavaThread *java_thread,
aoqi@0:                               jint start_depth, jint max_count,
aoqi@0:                               jvmtiFrameInfo* frame_buffer, jint* count_ptr) {
aoqi@0: #ifdef ASSERT
aoqi@0:   uint32_t debug_bits = 0;
aoqi@0: #endif
aoqi@0:   assert((SafepointSynchronize::is_at_safepoint() ||
aoqi@0:           is_thread_fully_suspended(java_thread, false, &debug_bits)),
aoqi@0:          "at safepoint or target thread is suspended");
aoqi@0:   int count = 0;
aoqi@0:   if (java_thread->has_last_Java_frame()) {
aoqi@0:     RegisterMap reg_map(java_thread);
aoqi@0:     Thread* current_thread = Thread::current();
aoqi@0:     ResourceMark rm(current_thread);
aoqi@0:     javaVFrame *jvf = java_thread->last_java_vframe(&reg_map);
aoqi@0:     HandleMark hm(current_thread);
aoqi@0:     if (start_depth != 0) {
aoqi@0:       if (start_depth > 0) {
aoqi@0:         for (int j = 0; j < start_depth && jvf != NULL; j++) {
aoqi@0:           jvf = jvf->java_sender();
aoqi@0:         }
aoqi@0:         if (jvf == NULL) {
aoqi@0:           // start_depth is deeper than the stack depth
aoqi@0:           return JVMTI_ERROR_ILLEGAL_ARGUMENT;
aoqi@0:         }
aoqi@0:       } else { // start_depth < 0
aoqi@0:         // we are referencing the starting depth based on the oldest
aoqi@0:         // part of the stack.
aoqi@0:         // optimize to limit the number of times that java_sender() is called
aoqi@0:         javaVFrame *jvf_cursor = jvf;
aoqi@0:         javaVFrame *jvf_prev = NULL;
aoqi@0:         javaVFrame *jvf_prev_prev;
aoqi@0:         int j = 0;
aoqi@0:         while (jvf_cursor != NULL) {
aoqi@0:           jvf_prev_prev = jvf_prev;
aoqi@0:           jvf_prev = jvf_cursor;
aoqi@0:           for (j = 0; j > start_depth && jvf_cursor != NULL; j--) {
aoqi@0:             jvf_cursor = jvf_cursor->java_sender();
aoqi@0:           }
aoqi@0:         }
aoqi@0:         if (j == start_depth) {
aoqi@0:           // previous pointer is exactly where we want to start
aoqi@0:           jvf = jvf_prev;
aoqi@0:         } else {
aoqi@0:           // we need to back up further to get to the right place
aoqi@0:           if (jvf_prev_prev == NULL) {
aoqi@0:             // the -start_depth is greater than the stack depth
aoqi@0:             return JVMTI_ERROR_ILLEGAL_ARGUMENT;
aoqi@0:           }
aoqi@0:           // j now is the number of frames on the stack starting with
aoqi@0:           // jvf_prev, we start from jvf_prev_prev and move older on
aoqi@0:           // the stack that many, the result is -start_depth frames
aoqi@0:           // remaining.
aoqi@0:           jvf = jvf_prev_prev;
aoqi@0:           for (; j < 0; j++) {
aoqi@0:             jvf = jvf->java_sender();
aoqi@0:           }
aoqi@0:         }
aoqi@0:       }
aoqi@0:     }
aoqi@0:     for (; count < max_count && jvf != NULL; count++) {
aoqi@0:       frame_buffer[count].method = jvf->method()->jmethod_id();
aoqi@0:       frame_buffer[count].location = (jvf->method()->is_native() ? -1 : jvf->bci());
aoqi@0:       jvf = jvf->java_sender();
aoqi@0:     }
aoqi@0:   } else {
aoqi@0:     if (start_depth != 0) {
aoqi@0:       // no frames and there is a starting depth
aoqi@0:       return JVMTI_ERROR_ILLEGAL_ARGUMENT;
aoqi@0:     }
aoqi@0:   }
aoqi@0:   *count_ptr = count;
aoqi@0:   return JVMTI_ERROR_NONE;
aoqi@0: }
aoqi@0: 
aoqi@0: jvmtiError
aoqi@0: JvmtiEnvBase::get_frame_count(JvmtiThreadState *state, jint *count_ptr) {
aoqi@0:   assert((state != NULL),
aoqi@0:          "JavaThread should create JvmtiThreadState before calling this method");
aoqi@0:   *count_ptr = state->count_frames();
aoqi@0:   return JVMTI_ERROR_NONE;
aoqi@0: }
aoqi@0: 
aoqi@0: jvmtiError
aoqi@0: JvmtiEnvBase::get_frame_location(JavaThread *java_thread, jint depth,
aoqi@0:                                  jmethodID* method_ptr, jlocation* location_ptr) {
aoqi@0: #ifdef ASSERT
aoqi@0:   uint32_t debug_bits = 0;
aoqi@0: #endif
aoqi@0:   assert((SafepointSynchronize::is_at_safepoint() ||
aoqi@0:           is_thread_fully_suspended(java_thread, false, &debug_bits)),
aoqi@0:          "at safepoint or target thread is suspended");
aoqi@0:   Thread* current_thread = Thread::current();
aoqi@0:   ResourceMark rm(current_thread);
aoqi@0: 
aoqi@0:   vframe *vf = vframeFor(java_thread, depth);
aoqi@0:   if (vf == NULL) {
aoqi@0:     return JVMTI_ERROR_NO_MORE_FRAMES;
aoqi@0:   }
aoqi@0: 
aoqi@0:   // vframeFor should return a java frame. If it doesn't
aoqi@0:   // it means we've got an internal error and we return the
aoqi@0:   // error in product mode. In debug mode we will instead
aoqi@0:   // attempt to cast the vframe to a javaVFrame and will
aoqi@0:   // cause an assertion/crash to allow further diagnosis.
aoqi@0: #ifdef PRODUCT
aoqi@0:   if (!vf->is_java_frame()) {
aoqi@0:     return JVMTI_ERROR_INTERNAL;
aoqi@0:   }
aoqi@0: #endif
aoqi@0: 
aoqi@0:   HandleMark hm(current_thread);
aoqi@0:   javaVFrame *jvf = javaVFrame::cast(vf);
aoqi@0:   Method* method = jvf->method();
aoqi@0:   if (method->is_native()) {
aoqi@0:     *location_ptr = -1;
aoqi@0:   } else {
aoqi@0:     *location_ptr = jvf->bci();
aoqi@0:   }
aoqi@0:   *method_ptr = method->jmethod_id();
aoqi@0: 
aoqi@0:   return JVMTI_ERROR_NONE;
aoqi@0: }
aoqi@0: 
aoqi@0: 
aoqi@0: jvmtiError
aoqi@0: JvmtiEnvBase::get_object_monitor_usage(JavaThread* calling_thread, jobject object, jvmtiMonitorUsage* info_ptr) {
aoqi@0:   HandleMark hm;
aoqi@0:   Handle hobj;
aoqi@0: 
aoqi@0:   bool at_safepoint = SafepointSynchronize::is_at_safepoint();
aoqi@0: 
aoqi@0:   // Check arguments
aoqi@0:   {
aoqi@0:     oop mirror = JNIHandles::resolve_external_guard(object);
aoqi@0:     NULL_CHECK(mirror, JVMTI_ERROR_INVALID_OBJECT);
aoqi@0:     NULL_CHECK(info_ptr, JVMTI_ERROR_NULL_POINTER);
aoqi@0: 
aoqi@0:     hobj = Handle(mirror);
aoqi@0:   }
aoqi@0: 
aoqi@0:   JavaThread *owning_thread = NULL;
aoqi@0:   ObjectMonitor *mon = NULL;
aoqi@0:   jvmtiMonitorUsage ret = {
aoqi@0:       NULL, 0, 0, NULL, 0, NULL
aoqi@0:   };
aoqi@0: 
aoqi@0:   uint32_t debug_bits = 0;
aoqi@0:   // first derive the object's owner and entry_count (if any)
aoqi@0:   {
aoqi@0:     // Revoke any biases before querying the mark word
aoqi@0:     if (SafepointSynchronize::is_at_safepoint()) {
aoqi@0:       BiasedLocking::revoke_at_safepoint(hobj);
aoqi@0:     } else {
aoqi@0:       BiasedLocking::revoke_and_rebias(hobj, false, calling_thread);
aoqi@0:     }
aoqi@0: 
aoqi@0:     address owner = NULL;
aoqi@0:     {
aoqi@0:       markOop mark = hobj()->mark();
aoqi@0: 
aoqi@0:       if (!mark->has_monitor()) {
aoqi@0:         // this object has a lightweight monitor
aoqi@0: 
aoqi@0:         if (mark->has_locker()) {
aoqi@0:           owner = (address)mark->locker(); // save the address of the Lock word
aoqi@0:         }
aoqi@0:         // implied else: no owner
aoqi@0:       } else {
aoqi@0:         // this object has a heavyweight monitor
aoqi@0:         mon = mark->monitor();
aoqi@0: 
aoqi@0:         // The owner field of a heavyweight monitor may be NULL for no
aoqi@0:         // owner, a JavaThread * or it may still be the address of the
aoqi@0:         // Lock word in a JavaThread's stack. A monitor can be inflated
aoqi@0:         // by a non-owning JavaThread, but only the owning JavaThread
aoqi@0:         // can change the owner field from the Lock word to the
aoqi@0:         // JavaThread * and it may not have done that yet.
aoqi@0:         owner = (address)mon->owner();
aoqi@0:       }
aoqi@0:     }
aoqi@0: 
aoqi@0:     if (owner != NULL) {
aoqi@0:       // This monitor is owned so we have to find the owning JavaThread.
aoqi@0:       // Since owning_thread_from_monitor_owner() grabs a lock, GC can
aoqi@0:       // move our object at this point. However, our owner value is safe
aoqi@0:       // since it is either the Lock word on a stack or a JavaThread *.
aoqi@0:       owning_thread = Threads::owning_thread_from_monitor_owner(owner, !at_safepoint);
aoqi@0:       // Cannot assume (owning_thread != NULL) here because this function
aoqi@0:       // may not have been called at a safepoint and the owning_thread
aoqi@0:       // might not be suspended.
aoqi@0:       if (owning_thread != NULL) {
aoqi@0:         // The monitor's owner either has to be the current thread, at safepoint
aoqi@0:         // or it has to be suspended. Any of these conditions will prevent both
aoqi@0:         // contending and waiting threads from modifying the state of
aoqi@0:         // the monitor.
aoqi@0:         if (!at_safepoint && !JvmtiEnv::is_thread_fully_suspended(owning_thread, true, &debug_bits)) {
aoqi@0:           // Don't worry! This return of JVMTI_ERROR_THREAD_NOT_SUSPENDED
aoqi@0:           // will not make it back to the JVM/TI agent. The error code will
aoqi@0:           // get intercepted in JvmtiEnv::GetObjectMonitorUsage() which
aoqi@0:           // will retry the call via a VM_GetObjectMonitorUsage VM op.
aoqi@0:           return JVMTI_ERROR_THREAD_NOT_SUSPENDED;
aoqi@0:         }
aoqi@0:         HandleMark hm;
aoqi@0:         Handle     th(owning_thread->threadObj());
aoqi@0:         ret.owner = (jthread)jni_reference(calling_thread, th);
aoqi@0:       }
aoqi@0:       // implied else: no owner
aoqi@0:     }
aoqi@0: 
aoqi@0:     if (owning_thread != NULL) {  // monitor is owned
aoqi@0:       if ((address)owning_thread == owner) {
aoqi@0:         // the owner field is the JavaThread *
aoqi@0:         assert(mon != NULL,
aoqi@0:           "must have heavyweight monitor with JavaThread * owner");
aoqi@0:         ret.entry_count = mon->recursions() + 1;
aoqi@0:       } else {
aoqi@0:         // The owner field is the Lock word on the JavaThread's stack
aoqi@0:         // so the recursions field is not valid. We have to count the
aoqi@0:         // number of recursive monitor entries the hard way. We pass
aoqi@0:         // a handle to survive any GCs along the way.
aoqi@0:         ResourceMark rm;
aoqi@0:         ret.entry_count = count_locked_objects(owning_thread, hobj);
aoqi@0:       }
aoqi@0:     }
aoqi@0:     // implied else: entry_count == 0
aoqi@0:   }
aoqi@0: 
aoqi@0:   int nWant,nWait;
aoqi@0:   if (mon != NULL) {
aoqi@0:     // this object has a heavyweight monitor
aoqi@0:     nWant = mon->contentions(); // # of threads contending for monitor
aoqi@0:     nWait = mon->waiters();     // # of threads in Object.wait()
aoqi@0:     ret.waiter_count = nWant + nWait;
aoqi@0:     ret.notify_waiter_count = nWait;
aoqi@0:   } else {
aoqi@0:     // this object has a lightweight monitor
aoqi@0:     ret.waiter_count = 0;
aoqi@0:     ret.notify_waiter_count = 0;
aoqi@0:   }
aoqi@0: 
aoqi@0:   // Allocate memory for heavyweight and lightweight monitor.
aoqi@0:   jvmtiError err;
aoqi@0:   err = allocate(ret.waiter_count * sizeof(jthread *), (unsigned char**)&ret.waiters);
aoqi@0:   if (err != JVMTI_ERROR_NONE) {
aoqi@0:     return err;
aoqi@0:   }
aoqi@0:   err = allocate(ret.notify_waiter_count * sizeof(jthread *),
aoqi@0:                  (unsigned char**)&ret.notify_waiters);
aoqi@0:   if (err != JVMTI_ERROR_NONE) {
aoqi@0:     deallocate((unsigned char*)ret.waiters);
aoqi@0:     return err;
aoqi@0:   }
aoqi@0: 
aoqi@0:   // now derive the rest of the fields
aoqi@0:   if (mon != NULL) {
aoqi@0:     // this object has a heavyweight monitor
aoqi@0: 
aoqi@0:     // Number of waiters may actually be less than the waiter count.
aoqi@0:     // So NULL out memory so that unused memory will be NULL.
aoqi@0:     memset(ret.waiters, 0, ret.waiter_count * sizeof(jthread *));
aoqi@0:     memset(ret.notify_waiters, 0, ret.notify_waiter_count * sizeof(jthread *));
aoqi@0: 
aoqi@0:     if (ret.waiter_count > 0) {
aoqi@0:       // we have contending and/or waiting threads
aoqi@0:       HandleMark hm;
aoqi@0:       if (nWant > 0) {
aoqi@0:         // we have contending threads
aoqi@0:         ResourceMark rm;
aoqi@0:         // get_pending_threads returns only java thread so we do not need to
aoqi@0:         // check for  non java threads.
aoqi@0:         GrowableArray<JavaThread*>* wantList = Threads::get_pending_threads(
aoqi@0:           nWant, (address)mon, !at_safepoint);
aoqi@0:         if (wantList->length() < nWant) {
aoqi@0:           // robustness: the pending list has gotten smaller
aoqi@0:           nWant = wantList->length();
aoqi@0:         }
aoqi@0:         for (int i = 0; i < nWant; i++) {
aoqi@0:           JavaThread *pending_thread = wantList->at(i);
aoqi@0:           // If the monitor has no owner, then a non-suspended contending
aoqi@0:           // thread could potentially change the state of the monitor by
aoqi@0:           // entering it. The JVM/TI spec doesn't allow this.
aoqi@0:           if (owning_thread == NULL && !at_safepoint &
aoqi@0:               !JvmtiEnv::is_thread_fully_suspended(pending_thread, true, &debug_bits)) {
aoqi@0:             if (ret.owner != NULL) {
aoqi@0:               destroy_jni_reference(calling_thread, ret.owner);
aoqi@0:             }
aoqi@0:             for (int j = 0; j < i; j++) {
aoqi@0:               destroy_jni_reference(calling_thread, ret.waiters[j]);
aoqi@0:             }
aoqi@0:             deallocate((unsigned char*)ret.waiters);
aoqi@0:             deallocate((unsigned char*)ret.notify_waiters);
aoqi@0:             return JVMTI_ERROR_THREAD_NOT_SUSPENDED;
aoqi@0:           }
aoqi@0:           Handle th(pending_thread->threadObj());
aoqi@0:           ret.waiters[i] = (jthread)jni_reference(calling_thread, th);
aoqi@0:         }
aoqi@0:       }
aoqi@0:       if (nWait > 0) {
aoqi@0:         // we have threads in Object.wait()
aoqi@0:         int offset = nWant;  // add after any contending threads
aoqi@0:         ObjectWaiter *waiter = mon->first_waiter();
aoqi@0:         for (int i = 0, j = 0; i < nWait; i++) {
aoqi@0:           if (waiter == NULL) {
aoqi@0:             // robustness: the waiting list has gotten smaller
aoqi@0:             nWait = j;
aoqi@0:             break;
aoqi@0:           }
aoqi@0:           Thread *t = mon->thread_of_waiter(waiter);
aoqi@0:           if (t != NULL && t->is_Java_thread()) {
aoqi@0:             JavaThread *wjava_thread = (JavaThread *)t;
aoqi@0:             // If the thread was found on the ObjectWaiter list, then
aoqi@0:             // it has not been notified. This thread can't change the
aoqi@0:             // state of the monitor so it doesn't need to be suspended.
aoqi@0:             Handle th(wjava_thread->threadObj());
aoqi@0:             ret.waiters[offset + j] = (jthread)jni_reference(calling_thread, th);
aoqi@0:             ret.notify_waiters[j++] = (jthread)jni_reference(calling_thread, th);
aoqi@0:           }
aoqi@0:           waiter = mon->next_waiter(waiter);
aoqi@0:         }
aoqi@0:       }
aoqi@0:     }
aoqi@0: 
aoqi@0:     // Adjust count. nWant and nWait count values may be less than original.
aoqi@0:     ret.waiter_count = nWant + nWait;
aoqi@0:     ret.notify_waiter_count = nWait;
aoqi@0:   } else {
aoqi@0:     // this object has a lightweight monitor and we have nothing more
aoqi@0:     // to do here because the defaults are just fine.
aoqi@0:   }
aoqi@0: 
aoqi@0:   // we don't update return parameter unless everything worked
aoqi@0:   *info_ptr = ret;
aoqi@0: 
aoqi@0:   return JVMTI_ERROR_NONE;
aoqi@0: }
aoqi@0: 
aoqi@0: ResourceTracker::ResourceTracker(JvmtiEnv* env) {
aoqi@0:   _env = env;
aoqi@0:   _allocations = new (ResourceObj::C_HEAP, mtInternal) GrowableArray<unsigned char*>(20, true);
aoqi@0:   _failed = false;
aoqi@0: }
aoqi@0: ResourceTracker::~ResourceTracker() {
aoqi@0:   if (_failed) {
aoqi@0:     for (int i=0; i<_allocations->length(); i++) {
aoqi@0:       _env->deallocate(_allocations->at(i));
aoqi@0:     }
aoqi@0:   }
aoqi@0:   delete _allocations;
aoqi@0: }
aoqi@0: 
aoqi@0: jvmtiError ResourceTracker::allocate(jlong size, unsigned char** mem_ptr) {
aoqi@0:   unsigned char *ptr;
aoqi@0:   jvmtiError err = _env->allocate(size, &ptr);
aoqi@0:   if (err == JVMTI_ERROR_NONE) {
aoqi@0:     _allocations->append(ptr);
aoqi@0:     *mem_ptr = ptr;
aoqi@0:   } else {
aoqi@0:     *mem_ptr = NULL;
aoqi@0:     _failed = true;
aoqi@0:   }
aoqi@0:   return err;
aoqi@0:  }
aoqi@0: 
aoqi@0: unsigned char* ResourceTracker::allocate(jlong size) {
aoqi@0:   unsigned char* ptr;
aoqi@0:   allocate(size, &ptr);
aoqi@0:   return ptr;
aoqi@0: }
aoqi@0: 
aoqi@0: char* ResourceTracker::strdup(const char* str) {
aoqi@0:   char *dup_str = (char*)allocate(strlen(str)+1);
aoqi@0:   if (dup_str != NULL) {
aoqi@0:     strcpy(dup_str, str);
aoqi@0:   }
aoqi@0:   return dup_str;
aoqi@0: }
aoqi@0: 
aoqi@0: struct StackInfoNode {
aoqi@0:   struct StackInfoNode *next;
aoqi@0:   jvmtiStackInfo info;
aoqi@0: };
aoqi@0: 
aoqi@0: // Create a jvmtiStackInfo inside a linked list node and create a
aoqi@0: // buffer for the frame information, both allocated as resource objects.
aoqi@0: // Fill in both the jvmtiStackInfo and the jvmtiFrameInfo.
aoqi@0: // Note that either or both of thr and thread_oop
aoqi@0: // may be null if the thread is new or has exited.
aoqi@0: void
aoqi@0: VM_GetMultipleStackTraces::fill_frames(jthread jt, JavaThread *thr, oop thread_oop) {
aoqi@0:   assert(SafepointSynchronize::is_at_safepoint(), "must be at safepoint");
aoqi@0: 
aoqi@0:   jint state = 0;
aoqi@0:   struct StackInfoNode *node = NEW_RESOURCE_OBJ(struct StackInfoNode);
aoqi@0:   jvmtiStackInfo *infop = &(node->info);
aoqi@0:   node->next = head();
aoqi@0:   set_head(node);
aoqi@0:   infop->frame_count = 0;
aoqi@0:   infop->thread = jt;
aoqi@0: 
aoqi@0:   if (thread_oop != NULL) {
aoqi@0:     // get most state bits
aoqi@0:     state = (jint)java_lang_Thread::get_thread_status(thread_oop);
aoqi@0:   }
aoqi@0: 
aoqi@0:   if (thr != NULL) {    // add more state bits if there is a JavaThead to query
aoqi@0:     // same as is_being_ext_suspended() but without locking
aoqi@0:     if (thr->is_ext_suspended() || thr->is_external_suspend()) {
aoqi@0:       state |= JVMTI_THREAD_STATE_SUSPENDED;
aoqi@0:     }
aoqi@0:     JavaThreadState jts = thr->thread_state();
aoqi@0:     if (jts == _thread_in_native) {
aoqi@0:       state |= JVMTI_THREAD_STATE_IN_NATIVE;
aoqi@0:     }
aoqi@0:     OSThread* osThread = thr->osthread();
aoqi@0:     if (osThread != NULL && osThread->interrupted()) {
aoqi@0:       state |= JVMTI_THREAD_STATE_INTERRUPTED;
aoqi@0:     }
aoqi@0:   }
aoqi@0:   infop->state = state;
aoqi@0: 
aoqi@0:   if (thr != NULL || (state & JVMTI_THREAD_STATE_ALIVE) != 0) {
aoqi@0:     infop->frame_buffer = NEW_RESOURCE_ARRAY(jvmtiFrameInfo, max_frame_count());
aoqi@0:     env()->get_stack_trace(thr, 0, max_frame_count(),
aoqi@0:                            infop->frame_buffer, &(infop->frame_count));
aoqi@0:   } else {
aoqi@0:     infop->frame_buffer = NULL;
aoqi@0:     infop->frame_count = 0;
aoqi@0:   }
aoqi@0:   _frame_count_total += infop->frame_count;
aoqi@0: }
aoqi@0: 
aoqi@0: // Based on the stack information in the linked list, allocate memory
aoqi@0: // block to return and fill it from the info in the linked list.
aoqi@0: void
aoqi@0: VM_GetMultipleStackTraces::allocate_and_fill_stacks(jint thread_count) {
aoqi@0:   // do I need to worry about alignment issues?
aoqi@0:   jlong alloc_size =  thread_count       * sizeof(jvmtiStackInfo)
aoqi@0:                     + _frame_count_total * sizeof(jvmtiFrameInfo);
aoqi@0:   env()->allocate(alloc_size, (unsigned char **)&_stack_info);
aoqi@0: 
aoqi@0:   // pointers to move through the newly allocated space as it is filled in
aoqi@0:   jvmtiStackInfo *si = _stack_info + thread_count;      // bottom of stack info
aoqi@0:   jvmtiFrameInfo *fi = (jvmtiFrameInfo *)si;            // is the top of frame info
aoqi@0: 
aoqi@0:   // copy information in resource area into allocated buffer
aoqi@0:   // insert stack info backwards since linked list is backwards
aoqi@0:   // insert frame info forwards
aoqi@0:   // walk the StackInfoNodes
aoqi@0:   for (struct StackInfoNode *sin = head(); sin != NULL; sin = sin->next) {
aoqi@0:     jint frame_count = sin->info.frame_count;
aoqi@0:     size_t frames_size = frame_count * sizeof(jvmtiFrameInfo);
aoqi@0:     --si;
aoqi@0:     memcpy(si, &(sin->info), sizeof(jvmtiStackInfo));
aoqi@0:     if (frames_size == 0) {
aoqi@0:       si->frame_buffer = NULL;
aoqi@0:     } else {
aoqi@0:       memcpy(fi, sin->info.frame_buffer, frames_size);
aoqi@0:       si->frame_buffer = fi;  // point to the new allocated copy of the frames
aoqi@0:       fi += frame_count;
aoqi@0:     }
aoqi@0:   }
aoqi@0:   assert(si == _stack_info, "the last copied stack info must be the first record");
aoqi@0:   assert((unsigned char *)fi == ((unsigned char *)_stack_info) + alloc_size,
aoqi@0:          "the last copied frame info must be the last record");
aoqi@0: }
aoqi@0: 
aoqi@0: 
aoqi@0: void
aoqi@0: VM_GetThreadListStackTraces::doit() {
aoqi@0:   assert(SafepointSynchronize::is_at_safepoint(), "must be at safepoint");
aoqi@0: 
aoqi@0:   ResourceMark rm;
aoqi@0:   for (int i = 0; i < _thread_count; ++i) {
aoqi@0:     jthread jt = _thread_list[i];
aoqi@0:     oop thread_oop = JNIHandles::resolve_external_guard(jt);
aoqi@0:     if (thread_oop == NULL || !thread_oop->is_a(SystemDictionary::Thread_klass())) {
aoqi@0:       set_result(JVMTI_ERROR_INVALID_THREAD);
aoqi@0:       return;
aoqi@0:     }
aoqi@0:     fill_frames(jt, java_lang_Thread::thread(thread_oop), thread_oop);
aoqi@0:   }
aoqi@0:   allocate_and_fill_stacks(_thread_count);
aoqi@0: }
aoqi@0: 
aoqi@0: void
aoqi@0: VM_GetAllStackTraces::doit() {
aoqi@0:   assert(SafepointSynchronize::is_at_safepoint(), "must be at safepoint");
aoqi@0: 
aoqi@0:   ResourceMark rm;
aoqi@0:   _final_thread_count = 0;
aoqi@0:   for (JavaThread *jt = Threads::first(); jt != NULL; jt = jt->next()) {
aoqi@0:     oop thread_oop = jt->threadObj();
aoqi@0:     if (thread_oop != NULL &&
aoqi@0:         !jt->is_exiting() &&
aoqi@0:         java_lang_Thread::is_alive(thread_oop) &&
aoqi@0:         !jt->is_hidden_from_external_view()) {
aoqi@0:       ++_final_thread_count;
aoqi@0:       // Handle block of the calling thread is used to create local refs.
aoqi@0:       fill_frames((jthread)JNIHandles::make_local(_calling_thread, thread_oop),
aoqi@0:                   jt, thread_oop);
aoqi@0:     }
aoqi@0:   }
aoqi@0:   allocate_and_fill_stacks(_final_thread_count);
aoqi@0: }
aoqi@0: 
aoqi@0: // Verifies that the top frame is a java frame in an expected state.
aoqi@0: // Deoptimizes frame if needed.
aoqi@0: // Checks that the frame method signature matches the return type (tos).
aoqi@0: // HandleMark must be defined in the caller only.
aoqi@0: // It is to keep a ret_ob_h handle alive after return to the caller.
aoqi@0: jvmtiError
aoqi@0: JvmtiEnvBase::check_top_frame(JavaThread* current_thread, JavaThread* java_thread,
aoqi@0:                               jvalue value, TosState tos, Handle* ret_ob_h) {
aoqi@0:   ResourceMark rm(current_thread);
aoqi@0: 
aoqi@0:   vframe *vf = vframeFor(java_thread, 0);
aoqi@0:   NULL_CHECK(vf, JVMTI_ERROR_NO_MORE_FRAMES);
aoqi@0: 
aoqi@0:   javaVFrame *jvf = (javaVFrame*) vf;
aoqi@0:   if (!vf->is_java_frame() || jvf->method()->is_native()) {
aoqi@0:     return JVMTI_ERROR_OPAQUE_FRAME;
aoqi@0:   }
aoqi@0: 
aoqi@0:   // If the frame is a compiled one, need to deoptimize it.
aoqi@0:   if (vf->is_compiled_frame()) {
aoqi@0:     if (!vf->fr().can_be_deoptimized()) {
aoqi@0:       return JVMTI_ERROR_OPAQUE_FRAME;
aoqi@0:     }
aoqi@0:     Deoptimization::deoptimize_frame(java_thread, jvf->fr().id());
aoqi@0:   }
aoqi@0: 
aoqi@0:   // Get information about method return type
aoqi@0:   Symbol* signature = jvf->method()->signature();
aoqi@0: 
aoqi@0:   ResultTypeFinder rtf(signature);
aoqi@0:   TosState fr_tos = as_TosState(rtf.type());
aoqi@0:   if (fr_tos != tos) {
aoqi@0:     if (tos != itos || (fr_tos != btos && fr_tos != ctos && fr_tos != stos)) {
aoqi@0:       return JVMTI_ERROR_TYPE_MISMATCH;
aoqi@0:     }
aoqi@0:   }
aoqi@0: 
aoqi@0:   // Check that the jobject class matches the return type signature.
aoqi@0:   jobject jobj = value.l;
aoqi@0:   if (tos == atos && jobj != NULL) { // NULL reference is allowed
aoqi@0:     Handle ob_h = Handle(current_thread, JNIHandles::resolve_external_guard(jobj));
aoqi@0:     NULL_CHECK(ob_h, JVMTI_ERROR_INVALID_OBJECT);
aoqi@0:     KlassHandle ob_kh = KlassHandle(current_thread, ob_h()->klass());
aoqi@0:     NULL_CHECK(ob_kh, JVMTI_ERROR_INVALID_OBJECT);
aoqi@0: 
aoqi@0:     // Method return type signature.
aoqi@0:     char* ty_sign = 1 + strchr(signature->as_C_string(), ')');
aoqi@0: 
aoqi@0:     if (!VM_GetOrSetLocal::is_assignable(ty_sign, ob_kh(), current_thread)) {
aoqi@0:       return JVMTI_ERROR_TYPE_MISMATCH;
aoqi@0:     }
aoqi@0:     *ret_ob_h = ob_h;
aoqi@0:   }
aoqi@0:   return JVMTI_ERROR_NONE;
aoqi@0: } /* end check_top_frame */
aoqi@0: 
aoqi@0: 
aoqi@0: // ForceEarlyReturn<type> follows the PopFrame approach in many aspects.
aoqi@0: // Main difference is on the last stage in the interpreter.
aoqi@0: // The PopFrame stops method execution to continue execution
aoqi@0: // from the same method call instruction.
aoqi@0: // The ForceEarlyReturn forces return from method so the execution
aoqi@0: // continues at the bytecode following the method call.
aoqi@0: 
aoqi@0: // Threads_lock NOT held, java_thread not protected by lock
aoqi@0: // java_thread - pre-checked
aoqi@0: 
aoqi@0: jvmtiError
aoqi@0: JvmtiEnvBase::force_early_return(JavaThread* java_thread, jvalue value, TosState tos) {
aoqi@0:   JavaThread* current_thread = JavaThread::current();
aoqi@0:   HandleMark   hm(current_thread);
aoqi@0:   uint32_t debug_bits = 0;
aoqi@0: 
aoqi@0:   // retrieve or create the state
aoqi@0:   JvmtiThreadState* state = JvmtiThreadState::state_for(java_thread);
aoqi@0:   if (state == NULL) {
aoqi@0:     return JVMTI_ERROR_THREAD_NOT_ALIVE;
aoqi@0:   }
aoqi@0: 
aoqi@0:   // Check if java_thread is fully suspended
aoqi@0:   if (!is_thread_fully_suspended(java_thread,
aoqi@0:                                  true /* wait for suspend completion */,
aoqi@0:                                  &debug_bits)) {
aoqi@0:     return JVMTI_ERROR_THREAD_NOT_SUSPENDED;
aoqi@0:   }
aoqi@0: 
aoqi@0:   // Check to see if a ForceEarlyReturn was already in progress
aoqi@0:   if (state->is_earlyret_pending()) {
aoqi@0:     // Probably possible for JVMTI clients to trigger this, but the
aoqi@0:     // JPDA backend shouldn't allow this to happen
aoqi@0:     return JVMTI_ERROR_INTERNAL;
aoqi@0:   }
aoqi@0:   {
aoqi@0:     // The same as for PopFrame. Workaround bug:
aoqi@0:     //  4812902: popFrame hangs if the method is waiting at a synchronize
aoqi@0:     // Catch this condition and return an error to avoid hanging.
aoqi@0:     // Now JVMTI spec allows an implementation to bail out with an opaque
aoqi@0:     // frame error.
aoqi@0:     OSThread* osThread = java_thread->osthread();
aoqi@0:     if (osThread->get_state() == MONITOR_WAIT) {
aoqi@0:       return JVMTI_ERROR_OPAQUE_FRAME;
aoqi@0:     }
aoqi@0:   }
aoqi@0:   Handle ret_ob_h = Handle();
aoqi@0:   jvmtiError err = check_top_frame(current_thread, java_thread, value, tos, &ret_ob_h);
aoqi@0:   if (err != JVMTI_ERROR_NONE) {
aoqi@0:     return err;
aoqi@0:   }
aoqi@0:   assert(tos != atos || value.l == NULL || ret_ob_h() != NULL,
aoqi@0:          "return object oop must not be NULL if jobject is not NULL");
aoqi@0: 
aoqi@0:   // Update the thread state to reflect that the top frame must be
aoqi@0:   // forced to return.
aoqi@0:   // The current frame will be returned later when the suspended
aoqi@0:   // thread is resumed and right before returning from VM to Java.
aoqi@0:   // (see call_VM_base() in assembler_<cpu>.cpp).
aoqi@0: 
aoqi@0:   state->set_earlyret_pending();
aoqi@0:   state->set_earlyret_oop(ret_ob_h());
aoqi@0:   state->set_earlyret_value(value, tos);
aoqi@0: 
aoqi@0:   // Set pending step flag for this early return.
aoqi@0:   // It is cleared when next step event is posted.
aoqi@0:   state->set_pending_step_for_earlyret();
aoqi@0: 
aoqi@0:   return JVMTI_ERROR_NONE;
aoqi@0: } /* end force_early_return */
aoqi@0: 
aoqi@0: void
aoqi@0: JvmtiMonitorClosure::do_monitor(ObjectMonitor* mon) {
aoqi@0:   if ( _error != JVMTI_ERROR_NONE) {
aoqi@0:     // Error occurred in previous iteration so no need to add
aoqi@0:     // to the list.
aoqi@0:     return;
aoqi@0:   }
aoqi@0:   if (mon->owner() == _java_thread ) {
aoqi@0:     // Filter out on stack monitors collected during stack walk.
aoqi@0:     oop obj = (oop)mon->object();
aoqi@0:     bool found = false;
aoqi@0:     for (int j = 0; j < _owned_monitors_list->length(); j++) {
aoqi@0:       jobject jobj = ((jvmtiMonitorStackDepthInfo*)_owned_monitors_list->at(j))->monitor;
aoqi@0:       oop check = JNIHandles::resolve(jobj);
aoqi@0:       if (check == obj) {
aoqi@0:         // On stack monitor already collected during the stack walk.
aoqi@0:         found = true;
aoqi@0:         break;
aoqi@0:       }
aoqi@0:     }
aoqi@0:     if (found == false) {
aoqi@0:       // This is off stack monitor (e.g. acquired via jni MonitorEnter).
aoqi@0:       jvmtiError err;
aoqi@0:       jvmtiMonitorStackDepthInfo *jmsdi;
aoqi@0:       err = _env->allocate(sizeof(jvmtiMonitorStackDepthInfo), (unsigned char **)&jmsdi);
aoqi@0:       if (err != JVMTI_ERROR_NONE) {
aoqi@0:         _error = err;
aoqi@0:         return;
aoqi@0:       }
aoqi@0:       Handle hobj(obj);
aoqi@0:       jmsdi->monitor = _env->jni_reference(_calling_thread, hobj);
aoqi@0:       // stack depth is unknown for this monitor.
aoqi@0:       jmsdi->stack_depth = -1;
aoqi@0:       _owned_monitors_list->append(jmsdi);
aoqi@0:     }
aoqi@0:   }
aoqi@0: }