You can not select more than 25 topics Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.

129 lines
5.0 KiB

/*
* Copyright (C) 2019 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_JNI_JNI_ID_MANAGER_H_
#define ART_RUNTIME_JNI_JNI_ID_MANAGER_H_
#include <jni.h>
#include <atomic>
#include <vector>
#include "art_field.h"
#include "art_method.h"
#include "base/mutex.h"
#include "gc_root.h"
#include "jni_id_type.h"
#include "reflective_value_visitor.h"
namespace art {
namespace mirror {
class Object;
class ClassExt;
} // namespace mirror
template<typename RT> class ReflectiveHandle;
namespace jni {
class ScopedEnableSuspendAllJniIdQueries;
class JniIdManager {
public:
template <typename T,
typename = typename std::enable_if<std::is_same_v<T, jmethodID> ||
std::is_same_v<T, jfieldID>>>
static constexpr bool IsIndexId(T val) {
return val == nullptr || reinterpret_cast<uintptr_t>(val) % 2 == 1;
}
void Init(Thread* self) REQUIRES_SHARED(Locks::mutator_lock_);
ArtMethod* DecodeMethodId(jmethodID method) REQUIRES(!Locks::jni_id_lock_);
ArtField* DecodeFieldId(jfieldID field) REQUIRES(!Locks::jni_id_lock_);
jmethodID EncodeMethodId(ReflectiveHandle<ArtMethod> method) REQUIRES(!Locks::jni_id_lock_)
REQUIRES_SHARED(Locks::mutator_lock_);
jmethodID EncodeMethodId(ArtMethod* method) REQUIRES(!Locks::jni_id_lock_)
REQUIRES_SHARED(Locks::mutator_lock_);
jfieldID EncodeFieldId(ReflectiveHandle<ArtField> field) REQUIRES(!Locks::jni_id_lock_)
REQUIRES_SHARED(Locks::mutator_lock_);
jfieldID EncodeFieldId(ArtField* field) REQUIRES(!Locks::jni_id_lock_)
REQUIRES_SHARED(Locks::mutator_lock_);
void VisitReflectiveTargets(ReflectiveValueVisitor* rvv)
REQUIRES(Locks::mutator_lock_, !Locks::jni_id_lock_);
void VisitRoots(RootVisitor* visitor) REQUIRES_SHARED(Locks::mutator_lock_);
ObjPtr<mirror::Object> GetPointerMarker() REQUIRES_SHARED(Locks::mutator_lock_);
private:
template <typename ArtType>
uintptr_t EncodeGenericId(ReflectiveHandle<ArtType> t) REQUIRES(!Locks::jni_id_lock_)
REQUIRES_SHARED(Locks::mutator_lock_);
template <typename ArtType>
ArtType* DecodeGenericId(uintptr_t input) REQUIRES(!Locks::jni_id_lock_);
template <typename ArtType> std::vector<ArtType*>& GetGenericMap()
REQUIRES(Locks::jni_id_lock_);
template <typename ArtType> uintptr_t GetNextId(JniIdType id)
REQUIRES_SHARED(Locks::mutator_lock_)
REQUIRES(Locks::jni_id_lock_);
template <typename ArtType>
size_t GetLinearSearchStartId(ReflectiveHandle<ArtType> t)
REQUIRES(Locks::jni_id_lock_)
REQUIRES_SHARED(Locks::mutator_lock_);
void StartDefer() REQUIRES(!Locks::jni_id_lock_) REQUIRES_SHARED(Locks::mutator_lock_);
void EndDefer() REQUIRES(!Locks::jni_id_lock_) REQUIRES_SHARED(Locks::mutator_lock_);
uintptr_t next_method_id_ GUARDED_BY(Locks::jni_id_lock_) = 1u;
std::vector<ArtMethod*> method_id_map_ GUARDED_BY(Locks::jni_id_lock_);
uintptr_t next_field_id_ GUARDED_BY(Locks::jni_id_lock_) = 1u;
std::vector<ArtField*> field_id_map_ GUARDED_BY(Locks::jni_id_lock_);
// If non-zero indicates that some thread is trying to allocate ids without being able to update
// the method->id mapping (due to not being able to allocate or something). In this case decode
// and encode need to do a linear scan of the lists. The ScopedEnableSuspendAllJniIdQueries struct
// will deal with fixing everything up.
size_t deferred_allocation_refcount_ GUARDED_BY(Locks::jni_id_lock_) = 0;
// min jmethodID that might not have it's method->id mapping filled in.
uintptr_t deferred_allocation_method_id_start_ GUARDED_BY(Locks::jni_id_lock_) = 0u;
// min jfieldID that might not have it's field->id mapping filled in.
uintptr_t deferred_allocation_field_id_start_ GUARDED_BY(Locks::jni_id_lock_) = 0u;
GcRoot<mirror::Object> pointer_marker_;
friend class ScopedEnableSuspendAllJniIdQueries;
// For GetPointerMarker
friend class mirror::ClassExt;
};
// A scope that will enable using the Encode/Decode JNI id functions with all threads suspended.
// This is required since normally we need to be able to allocate to encode new ids. This should
// only be used when absolutely required, for example to invoke user-callbacks during heap walking
// or similar.
class ScopedEnableSuspendAllJniIdQueries {
public:
ScopedEnableSuspendAllJniIdQueries() REQUIRES_SHARED(Locks::mutator_lock_);
~ScopedEnableSuspendAllJniIdQueries() REQUIRES_SHARED(Locks::mutator_lock_);
private:
JniIdManager* manager_;
};
} // namespace jni
} // namespace art
#endif // ART_RUNTIME_JNI_JNI_ID_MANAGER_H_