1 //===-- tsd.h ---------------------------------------------------*- C++ -*-===// 2 // 3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. 4 // See https://llvm.org/LICENSE.txt for license information. 5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception 6 // 7 //===----------------------------------------------------------------------===// 8 9 #ifndef SCUDO_TSD_H_ 10 #define SCUDO_TSD_H_ 11 12 #include "atomic_helpers.h" 13 #include "common.h" 14 #include "mutex.h" 15 16 #include <limits.h> // for PTHREAD_DESTRUCTOR_ITERATIONS 17 #include <pthread.h> 18 19 // With some build setups, this might still not be defined. 20 #ifndef PTHREAD_DESTRUCTOR_ITERATIONS 21 #define PTHREAD_DESTRUCTOR_ITERATIONS 4 22 #endif 23 24 namespace scudo { 25 26 template <class Allocator> struct alignas(SCUDO_CACHE_LINE_SIZE) TSD { 27 typename Allocator::CacheT Cache; 28 typename Allocator::QuarantineCacheT QuarantineCache; 29 using ThisT = TSD<Allocator>; 30 u8 DestructorIterations = 0; 31 32 void init(Allocator *Instance) { 33 DCHECK_EQ(DestructorIterations, 0U); 34 DCHECK(isAligned(reinterpret_cast<uptr>(this), alignof(ThisT))); 35 Instance->initCache(&Cache); 36 DestructorIterations = PTHREAD_DESTRUCTOR_ITERATIONS; 37 } 38 39 void commitBack(Allocator *Instance) { Instance->commitBack(this); } 40 41 inline bool tryLock() { 42 if (Mutex.tryLock()) { 43 atomic_store_relaxed(&Precedence, 0); 44 return true; 45 } 46 if (atomic_load_relaxed(&Precedence) == 0) 47 atomic_store_relaxed( 48 &Precedence, 49 static_cast<uptr>(getMonotonicTime() >> FIRST_32_SECOND_64(16, 0))); 50 return false; 51 } 52 inline void lock() { 53 atomic_store_relaxed(&Precedence, 0); 54 Mutex.lock(); 55 } 56 inline void unlock() { Mutex.unlock(); } 57 inline uptr getPrecedence() { return atomic_load_relaxed(&Precedence); } 58 59 private: 60 HybridMutex Mutex; 61 atomic_uptr Precedence = {}; 62 }; 63 64 } // namespace scudo 65 66 #endif // SCUDO_TSD_H_ 67