Merge "Add heuristic data race detection to sp<>" (04abdc61) · Commits · e / os / android_system_core

libutils/Android.bp

+1 −0

Original line number	Diff line number	Diff line
		@@ -45,6 +45,7 @@ cc_library {
		"StopWatch.cpp",
		"String8.cpp",
		"String16.cpp",
		"StrongPointer.cpp",
		"SystemClock.cpp",
		"Threads.cpp",
		"Timers.cpp",

libutils/StrongPointer.cpp

0 → 100644

+24 −0

Original line number	Diff line number	Diff line
		/*
		* Copyright (C) 2017 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.
		*/

		#define LOG_TAG "sp"

		#include <log/log.h>

		namespace android {

		void sp_report_race() { LOG_ALWAYS_FATAL("sp<> assignment detected data race"); }
		}

libutils/include/utils/StrongPointer.h

+26 −20

Original line number	Diff line number	Diff line
		@@ -108,6 +108,9 @@ private:
		T* m_ptr;
		};

		// For code size reasons, we do not want this inlined or templated.
		void sp_report_race();

		#undef COMPARE

		// ---------------------------------------------------------------------------
		@@ -161,19 +164,21 @@ sp<T>::~sp() {

		template<typename T>
		sp<T>& sp<T>::operator =(const sp<T>& other) {
		// Force m_ptr to be read twice, to heuristically check for data races.
		T* oldPtr(const_cast<T volatile*>(&m_ptr));
		T* otherPtr(other.m_ptr);
		if (otherPtr)
		otherPtr->incStrong(this);
		if (m_ptr)
		m_ptr->decStrong(this);
		if (otherPtr) otherPtr->incStrong(this);
		if (oldPtr) oldPtr->decStrong(this);
		if (oldPtr != const_cast<T volatile*>(&m_ptr)) sp_report_race();
		m_ptr = otherPtr;
		return *this;
		}

		template<typename T>
		sp<T>& sp<T>::operator =(sp<T>&& other) {
		if (m_ptr)
		m_ptr->decStrong(this);
		T* oldPtr(const_cast<T volatile*>(&m_ptr));
		if (oldPtr) oldPtr->decStrong(this);
		if (oldPtr != const_cast<T volatile*>(&m_ptr)) sp_report_race();
		m_ptr = other.m_ptr;
		other.m_ptr = nullptr;
		return *this;
		@@ -181,29 +186,30 @@ sp<T>& sp<T>::operator =(sp<T>&& other) {

		template<typename T>
		sp<T>& sp<T>::operator =(T* other) {
		if (other)
		other->incStrong(this);
		if (m_ptr)
		m_ptr->decStrong(this);
		T* oldPtr(const_cast<T volatile*>(&m_ptr));
		if (other) other->incStrong(this);
		if (oldPtr) oldPtr->decStrong(this);
		if (oldPtr != const_cast<T volatile*>(&m_ptr)) sp_report_race();
		m_ptr = other;
		return *this;
		}

		template<typename T> template<typename U>
		sp<T>& sp<T>::operator =(const sp<U>& other) {
		T* oldPtr(const_cast<T volatile*>(&m_ptr));
		T* otherPtr(other.m_ptr);
		if (otherPtr)
		otherPtr->incStrong(this);
		if (m_ptr)
		m_ptr->decStrong(this);
		if (otherPtr) otherPtr->incStrong(this);
		if (oldPtr) oldPtr->decStrong(this);
		if (oldPtr != const_cast<T volatile*>(&m_ptr)) sp_report_race();
		m_ptr = otherPtr;
		return *this;
		}

		template<typename T> template<typename U>
		sp<T>& sp<T>::operator =(sp<U>&& other) {
		if (m_ptr)
		m_ptr->decStrong(this);
		T* oldPtr(const_cast<T volatile*>(&m_ptr));
		if (m_ptr) m_ptr->decStrong(this);
		if (oldPtr != const_cast<T volatile*>(&m_ptr)) sp_report_race();
		m_ptr = other.m_ptr;
		other.m_ptr = nullptr;
		return *this;
		@@ -211,10 +217,10 @@ sp<T>& sp<T>::operator =(sp<U>&& other) {

		template<typename T> template<typename U>
		sp<T>& sp<T>::operator =(U* other) {
		if (other)
		(static_cast<T*>(other))->incStrong(this);
		if (m_ptr)
		m_ptr->decStrong(this);
		T* oldPtr(const_cast<T volatile*>(&m_ptr));
		if (other) (static_cast<T*>(other))->incStrong(this);
		if (oldPtr) oldPtr->decStrong(this);
		if (oldPtr != const_cast<T volatile*>(&m_ptr)) sp_report_race();
		m_ptr = other;
		return *this;
		}