/*
* Copyright (c) 1998, 2019, 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_PRIMS_JVMTIEXPORT_HPP
#define SHARE_PRIMS_JVMTIEXPORT_HPP
#include "jvmtifiles/jvmti.h"
#include "memory/allocation.hpp"
#include "memory/iterator.hpp"
#include "oops/oop.hpp"
#include "oops/oopsHierarchy.hpp"
#include "runtime/frame.hpp"
#include "runtime/handles.hpp"
#include "utilities/globalDefinitions.hpp"
#include "utilities/growableArray.hpp"
#include "utilities/macros.hpp"
// Must be included after jvmti.h.
#include "jvmticmlr.h"
// Forward declarations
class JvmtiEventControllerPrivate;
class JvmtiManageCapabilities;
class JvmtiEnv;
class JvmtiThreadState;
#define JVMTI_SUPPORT_FLAG(key) \
private: \
static bool _##key; \
public: \
inline static void set_##key(bool on) { \
JVMTI_ONLY(_##key = (on != 0)); \
NOT_JVMTI(report_unsupported(on)); \
} \
inline static bool key() { \
JVMTI_ONLY(return _##key); \
NOT_JVMTI(return false); \
}
// This class contains the JVMTI interface for the rest of hotspot.
//
class JvmtiExport : public AllStatic {
friend class VMStructs;
friend class CompileReplay;
private:
#if INCLUDE_JVMTI
static int _field_access_count;
static int _field_modification_count;
static bool _can_access_local_variables;
static bool _can_hotswap_or_post_breakpoint;
static bool _can_modify_any_class;
static bool _can_walk_any_space;
#endif // INCLUDE_JVMTI
JVMTI_SUPPORT_FLAG(can_get_source_debug_extension)
JVMTI_SUPPORT_FLAG(can_maintain_original_method_order)
JVMTI_SUPPORT_FLAG(can_post_interpreter_events)
JVMTI_SUPPORT_FLAG(can_post_on_exceptions)
JVMTI_SUPPORT_FLAG(can_post_breakpoint)
JVMTI_SUPPORT_FLAG(can_post_field_access)
JVMTI_SUPPORT_FLAG(can_post_field_modification)
JVMTI_SUPPORT_FLAG(can_post_method_entry)
JVMTI_SUPPORT_FLAG(can_post_method_exit)
JVMTI_SUPPORT_FLAG(can_pop_frame)
JVMTI_SUPPORT_FLAG(can_force_early_return)
JVMTI_SUPPORT_FLAG(early_vmstart_recorded)
JVMTI_SUPPORT_FLAG(can_get_owned_monitor_info) // includes can_get_owned_monitor_stack_depth_info
friend class JvmtiEventControllerPrivate; // should only modify these flags
JVMTI_SUPPORT_FLAG(should_post_single_step)
JVMTI_SUPPORT_FLAG(should_post_field_access)
JVMTI_SUPPORT_FLAG(should_post_field_modification)
JVMTI_SUPPORT_FLAG(should_post_class_load)
JVMTI_SUPPORT_FLAG(should_post_class_prepare)
JVMTI_SUPPORT_FLAG(should_post_class_unload)
JVMTI_SUPPORT_FLAG(should_post_native_method_bind)
JVMTI_SUPPORT_FLAG(should_post_compiled_method_load)
JVMTI_SUPPORT_FLAG(should_post_compiled_method_unload)
JVMTI_SUPPORT_FLAG(should_post_dynamic_code_generated)
JVMTI_SUPPORT_FLAG(should_post_monitor_contended_enter)
JVMTI_SUPPORT_FLAG(should_post_monitor_contended_entered)
JVMTI_SUPPORT_FLAG(should_post_monitor_wait)
JVMTI_SUPPORT_FLAG(should_post_monitor_waited)
JVMTI_SUPPORT_FLAG(should_post_data_dump)
JVMTI_SUPPORT_FLAG(should_post_garbage_collection_start)
JVMTI_SUPPORT_FLAG(should_post_garbage_collection_finish)
JVMTI_SUPPORT_FLAG(should_post_on_exceptions)
// ------ the below maybe don't have to be (but are for now)
// fixed conditions here ------------
// any events can be enabled
JVMTI_SUPPORT_FLAG(should_post_thread_life)
JVMTI_SUPPORT_FLAG(should_post_object_free)
JVMTI_SUPPORT_FLAG(should_post_resource_exhausted)
// we are holding objects on the heap - need to talk to GC - e.g.
// breakpoint info
JVMTI_SUPPORT_FLAG(should_clean_up_heap_objects)
JVMTI_SUPPORT_FLAG(should_post_vm_object_alloc)
JVMTI_SUPPORT_FLAG(should_post_sampled_object_alloc)
// If flag cannot be implemented, give an error if on=true
static void report_unsupported(bool on);
// these should only be called by the friend class
friend class JvmtiManageCapabilities;
inline static void set_can_modify_any_class(bool on) {
JVMTI_ONLY(_can_modify_any_class = (on != 0);)
}
inline static void set_can_access_local_variables(bool on) {
JVMTI_ONLY(_can_access_local_variables = (on != 0);)
}
inline static void set_can_hotswap_or_post_breakpoint(bool on) {
JVMTI_ONLY(_can_hotswap_or_post_breakpoint = (on != 0);)
}
inline static void set_can_walk_any_space(bool on) {
JVMTI_ONLY(_can_walk_any_space = (on != 0);)
}
enum {
JVMTI_VERSION_MASK = 0x70000000,
JVMTI_VERSION_VALUE = 0x30000000,
JVMDI_VERSION_VALUE = 0x20000000
};
static void post_field_modification(JavaThread *thread, Method* method, address location,
Klass* field_klass, Handle object, jfieldID field,
char sig_type, jvalue *value);
// posts a DynamicCodeGenerated event (internal/private implementation).
// The public post_dynamic_code_generated* functions make use of the
// internal implementation. Also called from JvmtiDeferredEvent::post()
static void post_dynamic_code_generated_internal(const char *name, const void *code_begin, const void *code_end) NOT_JVMTI_RETURN;
private:
// GenerateEvents support to allow posting of CompiledMethodLoad and
// DynamicCodeGenerated events for a given environment.
friend class JvmtiCodeBlobEvents;
static void post_compiled_method_load(JvmtiEnv* env, nmethod *nm) NOT_JVMTI_RETURN;
static void post_dynamic_code_generated(JvmtiEnv* env, const char *name, const void *code_begin,
const void *code_end) NOT_JVMTI_RETURN;
// This flag indicates whether RedefineClasses() has ever redefined
// one or more classes during the lifetime of the VM. The flag should
// only be set by the friend class and can be queried by other sub
// systems as needed to relax invariant checks.
static uint64_t _redefinition_count;
friend class VM_RedefineClasses;
inline static void increment_redefinition_count() {
JVMTI_ONLY(_redefinition_count++;)
}
// Flag to indicate if the compiler has recorded all dependencies. When the
// can_redefine_classes capability is enabled in the OnLoad phase then the compiler
// records all dependencies from startup. However if the capability is first
// enabled some time later then the dependencies recorded by the compiler
// are incomplete. This flag is used by RedefineClasses to know if the
// dependency information is complete or not.
static bool _all_dependencies_are_recorded;
public:
inline static bool has_redefined_a_class() {
JVMTI_ONLY(return _redefinition_count != 0);
NOT_JVMTI(return false);
}
// Only set in safepoint, so no memory ordering needed.
inline static uint64_t redefinition_count() {
JVMTI_ONLY(return _redefinition_count);
NOT_JVMTI(return 0);
}
inline static bool all_dependencies_are_recorded() {
return _all_dependencies_are_recorded;
}
inline static void set_all_dependencies_are_recorded(bool on) {
_all_dependencies_are_recorded = (on != 0);
}
// Add read edges to the unnamed modules of the bootstrap and app class loaders
static void add_default_read_edges(Handle h_module, TRAPS) NOT_JVMTI_RETURN;
// Add a read edge to the module
static jvmtiError add_module_reads(Handle module, Handle to_module, TRAPS);
// Updates a module to export a package
static jvmtiError add_module_exports(Handle module, Handle pkg_name, Handle to_module, TRAPS);
// Updates a module to open a package
static jvmtiError add_module_opens(Handle module, Handle pkg_name, Handle to_module, TRAPS);
// Add a used service to the module
static jvmtiError add_module_uses(Handle module, Handle service, TRAPS);
// Add a service provider to the module
static jvmtiError add_module_provides(Handle module, Handle service, Handle impl_class, TRAPS);
// let JVMTI know that the JVM_OnLoad code is running
static void enter_onload_phase() NOT_JVMTI_RETURN;
// let JVMTI know that the VM isn't up yet (and JVM_OnLoad code isn't running)
static void enter_primordial_phase() NOT_JVMTI_RETURN;
// let JVMTI know that the VM isn't up yet but JNI is live
static void enter_early_start_phase() NOT_JVMTI_RETURN;
static void enter_start_phase() NOT_JVMTI_RETURN;
// let JVMTI know that the VM is fully up and running now
static void enter_live_phase() NOT_JVMTI_RETURN;
// ------ can_* conditions (below) are set at OnLoad and never changed ------------
inline static bool can_modify_any_class() {
JVMTI_ONLY(return _can_modify_any_class);
NOT_JVMTI(return false);
}
inline static bool can_access_local_variables() {
JVMTI_ONLY(return _can_access_local_variables);
NOT_JVMTI(return false);
}
inline static bool can_hotswap_or_post_breakpoint() {
JVMTI_ONLY(return _can_hotswap_or_post_breakpoint);
NOT_JVMTI(return false);
}
inline static bool can_walk_any_space() {
JVMTI_ONLY(return _can_walk_any_space);
NOT_JVMTI(return false);
}
// field access management
static address get_field_access_count_addr() NOT_JVMTI_RETURN_(0);
// field modification management
static address get_field_modification_count_addr() NOT_JVMTI_RETURN_(0);
// -----------------
static bool is_jvmti_version(jint version) {
JVMTI_ONLY(return (version & JVMTI_VERSION_MASK) == JVMTI_VERSION_VALUE);
NOT_JVMTI(return false);
}
static bool is_jvmdi_version(jint version) {
JVMTI_ONLY(return (version & JVMTI_VERSION_MASK) == JVMDI_VERSION_VALUE);
NOT_JVMTI(return false);
}
static jint get_jvmti_interface(JavaVM *jvm, void **penv, jint version) NOT_JVMTI_RETURN_(0);
static void decode_version_values(jint version, int * major, int * minor,
int * micro) NOT_JVMTI_RETURN;
// single stepping management methods
static void at_single_stepping_point(JavaThread *thread, Method* method, address location) NOT_JVMTI_RETURN;
static void expose_single_stepping(JavaThread *thread) NOT_JVMTI_RETURN;
static bool hide_single_stepping(JavaThread *thread) NOT_JVMTI_RETURN_(false);
// Methods that notify the debugger that something interesting has happened in the VM.
static void post_early_vm_start () NOT_JVMTI_RETURN;
static void post_vm_start () NOT_JVMTI_RETURN;
static void post_vm_initialized () NOT_JVMTI_RETURN;
static void post_vm_death () NOT_JVMTI_RETURN;
static void post_single_step (JavaThread *thread, Method* method, address location) NOT_JVMTI_RETURN;
static void post_raw_breakpoint (JavaThread *thread, Method* method, address location) NOT_JVMTI_RETURN;
static void post_exception_throw (JavaThread *thread, Method* method, address location, oop exception) NOT_JVMTI_RETURN;
static void notice_unwind_due_to_exception (JavaThread *thread, Method* method, address location, oop exception, bool in_handler_frame) NOT_JVMTI_RETURN;
static oop jni_GetField_probe (JavaThread *thread, jobject jobj,
oop obj, Klass* klass, jfieldID fieldID, bool is_static)
NOT_JVMTI_RETURN_(NULL);
static oop jni_GetField_probe_nh (JavaThread *thread, jobject jobj,
oop obj, Klass* klass, jfieldID fieldID, bool is_static)
NOT_JVMTI_RETURN_(NULL);
static void post_field_access_by_jni (JavaThread *thread, oop obj,
Klass* klass, jfieldID fieldID, bool is_static) NOT_JVMTI_RETURN;
static void post_field_access (JavaThread *thread, Method* method,
address location, Klass* field_klass, Handle object, jfieldID field) NOT_JVMTI_RETURN;
static oop jni_SetField_probe (JavaThread *thread, jobject jobj,
oop obj, Klass* klass, jfieldID fieldID, bool is_static, char sig_type,
jvalue *value) NOT_JVMTI_RETURN_(NULL);
static oop jni_SetField_probe_nh (JavaThread *thread, jobject jobj,
oop obj, Klass* klass, jfieldID fieldID, bool is_static, char sig_type,
jvalue *value) NOT_JVMTI_RETURN_(NULL);
static void post_field_modification_by_jni(JavaThread *thread, oop obj,
Klass* klass, jfieldID fieldID, bool is_static, char sig_type,
jvalue *value);
static void post_raw_field_modification(JavaThread *thread, Method* method,
address location, Klass* field_klass, Handle object, jfieldID field,
char sig_type, jvalue *value) NOT_JVMTI_RETURN;
static void post_method_entry (JavaThread *thread, Method* method, frame current_frame) NOT_JVMTI_RETURN;
static void post_method_exit (JavaThread *thread, Method* method, frame current_frame) NOT_JVMTI_RETURN;
static void post_class_load (JavaThread *thread, Klass* klass) NOT_JVMTI_RETURN;
static void post_class_unload (Klass* klass) NOT_JVMTI_RETURN;
static void post_class_prepare (JavaThread *thread, Klass* klass) NOT_JVMTI_RETURN;
static void post_thread_start (JavaThread *thread) NOT_JVMTI_RETURN;
static void post_thread_end (JavaThread *thread) NOT_JVMTI_RETURN;
// Support for java.lang.instrument agent loading.
static bool _should_post_class_file_load_hook;
inline static void set_should_post_class_file_load_hook(bool on) { _should_post_class_file_load_hook = on; }
inline static bool should_post_class_file_load_hook() {
JVMTI_ONLY(return _should_post_class_file_load_hook);
NOT_JVMTI(return false;)
}
static bool is_early_phase() NOT_JVMTI_RETURN_(false);
static bool has_early_class_hook_env() NOT_JVMTI_RETURN_(false);
// Return true if the class was modified by the hook.
static bool post_class_file_load_hook(Symbol* h_name, Handle class_loader,
Handle h_protection_domain,
unsigned char **data_ptr, unsigned char **end_ptr,
JvmtiCachedClassFileData **cache_ptr) NOT_JVMTI_RETURN_(false);
static void post_native_method_bind(Method* method, address* function_ptr) NOT_JVMTI_RETURN;
static void post_compiled_method_load(nmethod *nm) NOT_JVMTI_RETURN;
static void post_dynamic_code_generated(const char *name, const void *code_begin, const void *code_end) NOT_JVMTI_RETURN;
// used to post a CompiledMethodUnload event
static void post_compiled_method_unload(jmethodID mid, const void *code_begin) NOT_JVMTI_RETURN;
// similiar to post_dynamic_code_generated except that it can be used to
// post a DynamicCodeGenerated event while holding locks in the VM. Any event
// posted using this function is recorded by the enclosing event collector
// -- JvmtiDynamicCodeEventCollector.
static void post_dynamic_code_generated_while_holding_locks(const char* name, address code_begin, address code_end) NOT_JVMTI_RETURN;
static void post_garbage_collection_finish() NOT_JVMTI_RETURN;
static void post_garbage_collection_start() NOT_JVMTI_RETURN;
static void post_data_dump() NOT_JVMTI_RETURN;
static void post_monitor_contended_enter(JavaThread *thread, ObjectMonitor *obj_mntr) NOT_JVMTI_RETURN;
static void post_monitor_contended_entered(JavaThread *thread, ObjectMonitor *obj_mntr) NOT_JVMTI_RETURN;
static void post_monitor_wait(JavaThread *thread, oop obj, jlong timeout) NOT_JVMTI_RETURN;
static void post_monitor_waited(JavaThread *thread, ObjectMonitor *obj_mntr, jboolean timed_out) NOT_JVMTI_RETURN;
static void post_object_free(JvmtiEnv* env, jlong tag) NOT_JVMTI_RETURN;
static void post_resource_exhausted(jint resource_exhausted_flags, const char* detail) NOT_JVMTI_RETURN;
static void record_vm_internal_object_allocation(oop object) NOT_JVMTI_RETURN;
// Post objects collected by vm_object_alloc_event_collector.
static void post_vm_object_alloc(JavaThread *thread, oop object) NOT_JVMTI_RETURN;
// Collects vm internal objects for later event posting.
inline static void vm_object_alloc_event_collector(oop object) {
if (should_post_vm_object_alloc()) {
record_vm_internal_object_allocation(object);
}
}
static void record_sampled_internal_object_allocation(oop object) NOT_JVMTI_RETURN;
// Post objects collected by sampled_object_alloc_event_collector.
static void post_sampled_object_alloc(JavaThread *thread, oop object) NOT_JVMTI_RETURN;
// Collects vm internal objects for later event posting.
inline static void sampled_object_alloc_event_collector(oop object) {
if (should_post_sampled_object_alloc()) {
record_sampled_internal_object_allocation(object);
}
}
inline static void post_array_size_exhausted() {
if (should_post_resource_exhausted()) {
post_resource_exhausted(JVMTI_RESOURCE_EXHAUSTED_OOM_ERROR,
"Requested array size exceeds VM limit");
}
}
static void cleanup_thread (JavaThread* thread) NOT_JVMTI_RETURN;
static void clear_detected_exception (JavaThread* thread) NOT_JVMTI_RETURN;
static void oops_do(OopClosure* f) NOT_JVMTI_RETURN;
static void weak_oops_do(BoolObjectClosure* b, OopClosure* f) NOT_JVMTI_RETURN;
static void transition_pending_onload_raw_monitors() NOT_JVMTI_RETURN;
#if INCLUDE_SERVICES
// attach support
static jint load_agent_library(const char *agent, const char *absParam, const char *options, outputStream* out) NOT_JVMTI_RETURN_(JNI_ERR);
#endif
// SetNativeMethodPrefix support
static char** get_all_native_method_prefixes(int* count_ptr) NOT_JVMTI_RETURN_(NULL);
// JavaThread lifecycle support:
static jvmtiError cv_external_thread_to_JavaThread(ThreadsList * t_list,
jthread thread,
JavaThread ** jt_pp,
oop * thread_oop_p);
static jvmtiError cv_oop_to_JavaThread(ThreadsList * t_list, oop thread_oop,
JavaThread ** jt_pp);
};
// Support class used by JvmtiDynamicCodeEventCollector and others. It
// describes a single code blob by name and address range.
class JvmtiCodeBlobDesc : public CHeapObj<mtInternal> {
private:
char _name[64];
address _code_begin;
address _code_end;
public:
JvmtiCodeBlobDesc(const char *name, address code_begin, address code_end) {
assert(name != NULL, "all code blobs must be named");
strncpy(_name, name, sizeof(_name) - 1);
_name[sizeof(_name)-1] = '\0';
_code_begin = code_begin;
_code_end = code_end;
}
char* name() { return _name; }
address code_begin() { return _code_begin; }
address code_end() { return _code_end; }
};
// JvmtiEventCollector is a helper class to setup thread for
// event collection.
class JvmtiEventCollector : public StackObj {
private:
JvmtiEventCollector* _prev; // Save previous one to support nested event collector.
bool _unset_jvmti_thread_state;
public:
JvmtiEventCollector() : _prev(NULL), _unset_jvmti_thread_state(false) {}
void setup_jvmti_thread_state(); // Set this collector in current thread, returns if success.
void unset_jvmti_thread_state(); // Reset previous collector in current thread.
virtual bool is_dynamic_code_event() { return false; }
virtual bool is_vm_object_alloc_event(){ return false; }
virtual bool is_sampled_object_alloc_event(){ return false; }
JvmtiEventCollector *get_prev() { return _prev; }
};
// A JvmtiDynamicCodeEventCollector is a helper class for the JvmtiExport
// interface. It collects "dynamic code generated" events that are posted
// while holding locks. When the event collector goes out of scope the
// events will be posted.
//
// Usage :-
//
// {
// JvmtiDynamicCodeEventCollector event_collector;
// :
// { MutexLocker ml(...)
// :
// JvmtiExport::post_dynamic_code_generated_while_holding_locks(...)
// }
// // event collector goes out of scope => post events to profiler.
// }
class JvmtiDynamicCodeEventCollector : public JvmtiEventCollector {
private:
GrowableArray<JvmtiCodeBlobDesc*>* _code_blobs; // collected code blob events
friend class JvmtiExport;
void register_stub(const char* name, address start, address end);
public:
JvmtiDynamicCodeEventCollector() NOT_JVMTI_RETURN;
~JvmtiDynamicCodeEventCollector() NOT_JVMTI_RETURN;
bool is_dynamic_code_event() { return true; }
};
// Used as a base class for object allocation collection and then posting
// the allocations to any event notification callbacks.
//
class JvmtiObjectAllocEventCollector : public JvmtiEventCollector {
protected:
GrowableArray<oop>* _allocated; // field to record collected allocated object oop.
bool _enable; // This flag is enabled in constructor if set up in the thread state
// and disabled in destructor before posting event. To avoid
// collection of objects allocated while running java code inside
// agent post_X_object_alloc() event handler.
void (*_post_callback)(JavaThread*, oop); // what callback to use when destroying the collector.
//GC support
void oops_do(OopClosure* f);
friend class JvmtiExport;
// Record allocated object oop.
inline void record_allocation(oop obj);
//GC support
static void oops_do_for_all_threads(OopClosure* f);
public:
JvmtiObjectAllocEventCollector() NOT_JVMTI_RETURN;
void generate_call_for_allocated();
bool is_enabled() { return _enable; }
void set_enabled(bool on) { _enable = on; }
};
// Used to record vm internally allocated object oops and post
// vm object alloc event for objects visible to java world.
// Constructor enables JvmtiThreadState flag and all vm allocated
// objects are recorded in a growable array. When destructor is
// called the vm object alloc event is posted for each object
// visible to java world.
// See jvm.cpp file for its usage.
//
class JvmtiVMObjectAllocEventCollector : public JvmtiObjectAllocEventCollector {
public:
JvmtiVMObjectAllocEventCollector() NOT_JVMTI_RETURN;
~JvmtiVMObjectAllocEventCollector() NOT_JVMTI_RETURN;
virtual bool is_vm_object_alloc_event() { return true; }
};
// Used to record sampled allocated object oops and post
// sampled object alloc event.
// Constructor enables JvmtiThreadState flag and all sampled allocated
// objects are recorded in a growable array. When destructor is
// called the sampled object alloc event is posted for each sampled object.
// See jvm.cpp file for its usage.
//
class JvmtiSampledObjectAllocEventCollector : public JvmtiObjectAllocEventCollector {
public:
JvmtiSampledObjectAllocEventCollector() NOT_JVMTI_RETURN;
~JvmtiSampledObjectAllocEventCollector() NOT_JVMTI_RETURN;
bool is_sampled_object_alloc_event() { return true; }
static bool object_alloc_is_safe_to_sample() NOT_JVMTI_RETURN_(false);
};
// Marker class to disable the posting of VMObjectAlloc events
// within its scope.
//
// Usage :-
//
// {
// NoJvmtiVMObjectAllocMark njm;
// :
// // VMObjAlloc event will not be posted
// JvmtiExport::vm_object_alloc_event_collector(obj);
// :
// }
class NoJvmtiVMObjectAllocMark : public StackObj {
private:
// enclosing collector if enabled, NULL otherwise
JvmtiVMObjectAllocEventCollector *_collector;
bool was_enabled() { return _collector != NULL; }
public:
NoJvmtiVMObjectAllocMark() NOT_JVMTI_RETURN;
~NoJvmtiVMObjectAllocMark() NOT_JVMTI_RETURN;
};
// Base class for reporting GC events to JVMTI.
class JvmtiGCMarker : public StackObj {
public:
JvmtiGCMarker() NOT_JVMTI_RETURN;
~JvmtiGCMarker() NOT_JVMTI_RETURN;
};
// JvmtiHideSingleStepping is a helper class for hiding
// internal single step events.
class JvmtiHideSingleStepping : public StackObj {
private:
bool _single_step_hidden;
JavaThread * _thread;
public:
JvmtiHideSingleStepping(JavaThread * thread) {
assert(thread != NULL, "sanity check");
_single_step_hidden = false;
_thread = thread;
if (JvmtiExport::should_post_single_step()) {
_single_step_hidden = JvmtiExport::hide_single_stepping(_thread);
}
}
~JvmtiHideSingleStepping() {
if (_single_step_hidden) {
JvmtiExport::expose_single_stepping(_thread);
}
}
};
#endif // SHARE_PRIMS_JVMTIEXPORT_HPP