1 //===-- tsan_sync.h ---------------------------------------------*- C++ -*-===// 2 // 3 // This file is distributed under the University of Illinois Open Source 4 // License. See LICENSE.TXT for details. 5 // 6 //===----------------------------------------------------------------------===// 7 // 8 // This file is a part of ThreadSanitizer (TSan), a race detector. 9 // 10 //===----------------------------------------------------------------------===// 11 #ifndef TSAN_SYNC_H 12 #define TSAN_SYNC_H 13 14 #include "sanitizer_common/sanitizer_atomic.h" 15 #include "sanitizer_common/sanitizer_common.h" 16 #include "sanitizer_common/sanitizer_deadlock_detector_interface.h" 17 #include "tsan_defs.h" 18 #include "tsan_clock.h" 19 #include "tsan_mutex.h" 20 #include "tsan_dense_alloc.h" 21 22 namespace __tsan { 23 24 struct SyncVar { 25 SyncVar(); 26 27 static const int kInvalidTid = -1; 28 29 uptr addr; // overwritten by DenseSlabAlloc freelist 30 Mutex mtx; 31 u64 uid; // Globally unique id. 32 u32 creation_stack_id; 33 int owner_tid; // Set only by exclusive owners. 34 u64 last_lock; 35 int recursion; 36 bool is_rw; 37 bool is_recursive; 38 bool is_broken; 39 bool is_linker_init; 40 u32 next; // in MetaMap 41 DDMutex dd; 42 SyncClock read_clock; // Used for rw mutexes only. 43 // The clock is placed last, so that it is situated on a different cache line 44 // with the mtx. This reduces contention for hot sync objects. 45 SyncClock clock; 46 47 void Init(ThreadState *thr, uptr pc, uptr addr, u64 uid); 48 void Reset(ThreadState *thr); 49 50 u64 GetId() const { 51 // 47 lsb is addr, then 14 bits is low part of uid, then 3 zero bits. 52 return GetLsb((u64)addr | (uid << 47), 61); 53 } 54 bool CheckId(u64 uid) const { 55 CHECK_EQ(uid, GetLsb(uid, 14)); 56 return GetLsb(this->uid, 14) == uid; 57 } 58 static uptr SplitId(u64 id, u64 *uid) { 59 *uid = id >> 47; 60 return (uptr)GetLsb(id, 47); 61 } 62 }; 63 64 /* MetaMap allows to map arbitrary user pointers onto various descriptors. 65 Currently it maps pointers to heap block descriptors and sync var descs. 66 It uses 1/2 direct shadow, see tsan_platform.h. 67 */ 68 class MetaMap { 69 public: 70 MetaMap(); 71 72 void AllocBlock(ThreadState *thr, uptr pc, uptr p, uptr sz); 73 uptr FreeBlock(ThreadState *thr, uptr pc, uptr p); 74 void FreeRange(ThreadState *thr, uptr pc, uptr p, uptr sz); 75 MBlock* GetBlock(uptr p); 76 77 SyncVar* GetOrCreateAndLock(ThreadState *thr, uptr pc, 78 uptr addr, bool write_lock); 79 SyncVar* GetIfExistsAndLock(uptr addr); 80 81 void MoveMemory(uptr src, uptr dst, uptr sz); 82 83 void OnThreadIdle(ThreadState *thr); 84 85 private: 86 static const u32 kFlagMask = 3 << 30; 87 static const u32 kFlagBlock = 1 << 30; 88 static const u32 kFlagSync = 2 << 30; 89 typedef DenseSlabAlloc<MBlock, 1<<16, 1<<12> BlockAlloc; 90 typedef DenseSlabAlloc<SyncVar, 1<<16, 1<<10> SyncAlloc; 91 BlockAlloc block_alloc_; 92 SyncAlloc sync_alloc_; 93 atomic_uint64_t uid_gen_; 94 95 SyncVar* GetAndLock(ThreadState *thr, uptr pc, uptr addr, bool write_lock, 96 bool create); 97 }; 98 99 } // namespace __tsan 100 101 #endif // TSAN_SYNC_H 102