/*
* Copyright (C) 2016 The Android Open Source Project
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
#ifndef ART_RUNTIME_OPENJDKJVMTI_EVENTS_H_
#define ART_RUNTIME_OPENJDKJVMTI_EVENTS_H_
#include <bitset>
#include <vector>
#include "base/logging.h"
#include "jvmti.h"
#include "thread.h"
namespace openjdkjvmti {
struct ArtJvmTiEnv;
class JvmtiAllocationListener;
class JvmtiGcPauseListener;
// an enum for ArtEvents. This differs from the JVMTI events only in that we distinguish between
// retransformation capable and incapable loading
enum class ArtJvmtiEvent {
kMinEventTypeVal = JVMTI_MIN_EVENT_TYPE_VAL,
kVmInit = JVMTI_EVENT_VM_INIT,
kVmDeath = JVMTI_EVENT_VM_DEATH,
kThreadStart = JVMTI_EVENT_THREAD_START,
kThreadEnd = JVMTI_EVENT_THREAD_END,
kClassFileLoadHookNonRetransformable = JVMTI_EVENT_CLASS_FILE_LOAD_HOOK,
kClassLoad = JVMTI_EVENT_CLASS_LOAD,
kClassPrepare = JVMTI_EVENT_CLASS_PREPARE,
kVmStart = JVMTI_EVENT_VM_START,
kException = JVMTI_EVENT_EXCEPTION,
kExceptionCatch = JVMTI_EVENT_EXCEPTION_CATCH,
kSingleStep = JVMTI_EVENT_SINGLE_STEP,
kFramePop = JVMTI_EVENT_FRAME_POP,
kBreakpoint = JVMTI_EVENT_BREAKPOINT,
kFieldAccess = JVMTI_EVENT_FIELD_ACCESS,
kFieldModification = JVMTI_EVENT_FIELD_MODIFICATION,
kMethodEntry = JVMTI_EVENT_METHOD_ENTRY,
kMethodExit = JVMTI_EVENT_METHOD_EXIT,
kNativeMethodBind = JVMTI_EVENT_NATIVE_METHOD_BIND,
kCompiledMethodLoad = JVMTI_EVENT_COMPILED_METHOD_LOAD,
kCompiledMethodUnload = JVMTI_EVENT_COMPILED_METHOD_UNLOAD,
kDynamicCodeGenerated = JVMTI_EVENT_DYNAMIC_CODE_GENERATED,
kDataDumpRequest = JVMTI_EVENT_DATA_DUMP_REQUEST,
kMonitorWait = JVMTI_EVENT_MONITOR_WAIT,
kMonitorWaited = JVMTI_EVENT_MONITOR_WAITED,
kMonitorContendedEnter = JVMTI_EVENT_MONITOR_CONTENDED_ENTER,
kMonitorContendedEntered = JVMTI_EVENT_MONITOR_CONTENDED_ENTERED,
kResourceExhausted = JVMTI_EVENT_RESOURCE_EXHAUSTED,
kGarbageCollectionStart = JVMTI_EVENT_GARBAGE_COLLECTION_START,
kGarbageCollectionFinish = JVMTI_EVENT_GARBAGE_COLLECTION_FINISH,
kObjectFree = JVMTI_EVENT_OBJECT_FREE,
kVmObjectAlloc = JVMTI_EVENT_VM_OBJECT_ALLOC,
kClassFileLoadHookRetransformable = JVMTI_MAX_EVENT_TYPE_VAL + 1,
kMaxEventTypeVal = kClassFileLoadHookRetransformable,
};
// Convert a jvmtiEvent into a ArtJvmtiEvent
ALWAYS_INLINE static inline ArtJvmtiEvent GetArtJvmtiEvent(ArtJvmTiEnv* env, jvmtiEvent e);
static inline jvmtiEvent GetJvmtiEvent(ArtJvmtiEvent e) {
if (UNLIKELY(e == ArtJvmtiEvent::kClassFileLoadHookRetransformable)) {
return JVMTI_EVENT_CLASS_FILE_LOAD_HOOK;
} else {
return static_cast<jvmtiEvent>(e);
}
}
struct EventMask {
static constexpr size_t kEventsSize =
static_cast<size_t>(ArtJvmtiEvent::kMaxEventTypeVal) -
static_cast<size_t>(ArtJvmtiEvent::kMinEventTypeVal) + 1;
std::bitset<kEventsSize> bit_set;
static bool EventIsInRange(ArtJvmtiEvent event) {
return event >= ArtJvmtiEvent::kMinEventTypeVal && event <= ArtJvmtiEvent::kMaxEventTypeVal;
}
void Set(ArtJvmtiEvent event, bool value = true) {
DCHECK(EventIsInRange(event));
bit_set.set(static_cast<size_t>(event) - static_cast<size_t>(ArtJvmtiEvent::kMinEventTypeVal),
value);
}
bool Test(ArtJvmtiEvent event) const {
DCHECK(EventIsInRange(event));
return bit_set.test(
static_cast<size_t>(event) - static_cast<size_t>(ArtJvmtiEvent::kMinEventTypeVal));
}
};
struct EventMasks {
// The globally enabled events.
EventMask global_event_mask;
// The per-thread enabled events.
// It is not enough to store a Thread pointer, as these may be reused. Use the pointer and the
// thread id.
// Note: We could just use the tid like tracing does.
using UniqueThread = std::pair<art::Thread*, uint32_t>;
// TODO: Native thread objects are immovable, so we can use them as keys in an (unordered) map,
// if necessary.
std::vector<std::pair<UniqueThread, EventMask>> thread_event_masks;
// A union of the per-thread events, for fast-pathing.
EventMask unioned_thread_event_mask;
EventMask& GetEventMask(art::Thread* thread);
EventMask* GetEventMaskOrNull(art::Thread* thread);
void EnableEvent(art::Thread* thread, ArtJvmtiEvent event);
void DisableEvent(art::Thread* thread, ArtJvmtiEvent event);
bool IsEnabledAnywhere(ArtJvmtiEvent event);
// Make any changes to event masks needed for the given capability changes. If caps_added is true
// then caps is all the newly set capabilities of the jvmtiEnv. If it is false then caps is the
// set of all capabilities that were removed from the jvmtiEnv.
void HandleChangedCapabilities(const jvmtiCapabilities& caps, bool caps_added);
};
// Helper class for event handling.
class EventHandler {
public:
EventHandler();
~EventHandler();
// Register an env. It is assumed that this happens on env creation, that is, no events are
// enabled, yet.
void RegisterArtJvmTiEnv(ArtJvmTiEnv* env);
// Remove an env.
void RemoveArtJvmTiEnv(ArtJvmTiEnv* env);
bool IsEventEnabledAnywhere(ArtJvmtiEvent event) const {
if (!EventMask::EventIsInRange(event)) {
return false;
}
return global_mask.Test(event);
}
jvmtiError SetEvent(ArtJvmTiEnv* env,
art::Thread* thread,
ArtJvmtiEvent event,
jvmtiEventMode mode);
// Dispatch event to all registered environments.
template <ArtJvmtiEvent kEvent, typename ...Args>
ALWAYS_INLINE
inline void DispatchEvent(art::Thread* thread, Args... args) const;
// Dispatch event to the given environment, only.
template <ArtJvmtiEvent kEvent, typename ...Args>
ALWAYS_INLINE
inline void DispatchEvent(ArtJvmTiEnv* env, art::Thread* thread, Args... args) const;
// Tell the event handler capabilities were added/lost so it can adjust the sent events.If
// caps_added is true then caps is all the newly set capabilities of the jvmtiEnv. If it is false
// then caps is the set of all capabilities that were removed from the jvmtiEnv.
ALWAYS_INLINE
inline void HandleChangedCapabilities(ArtJvmTiEnv* env,
const jvmtiCapabilities& caps,
bool added);
private:
template <ArtJvmtiEvent kEvent>
ALWAYS_INLINE
static inline bool ShouldDispatch(ArtJvmTiEnv* env, art::Thread* thread);
ALWAYS_INLINE
inline bool NeedsEventUpdate(ArtJvmTiEnv* env,
const jvmtiCapabilities& caps,
bool added);
// Recalculates the event mask for the given event.
ALWAYS_INLINE
inline void RecalculateGlobalEventMask(ArtJvmtiEvent event);
template <ArtJvmtiEvent kEvent>
ALWAYS_INLINE inline void DispatchClassFileLoadHookEvent(art::Thread* thread,
JNIEnv* jnienv,
jclass class_being_redefined,
jobject loader,
const char* name,
jobject protection_domain,
jint class_data_len,
const unsigned char* class_data,
jint* new_class_data_len,
unsigned char** new_class_data) const;
void HandleEventType(ArtJvmtiEvent event, bool enable);
// List of all JvmTiEnv objects that have been created, in their creation order.
// NB Some elements might be null representing envs that have been deleted. They should be skipped
// anytime this list is used.
std::vector<ArtJvmTiEnv*> envs;
// A union of all enabled events, anywhere.
EventMask global_mask;
std::unique_ptr<JvmtiAllocationListener> alloc_listener_;
std::unique_ptr<JvmtiGcPauseListener> gc_pause_listener_;
};
} // namespace openjdkjvmti
#endif // ART_RUNTIME_OPENJDKJVMTI_EVENTS_H_