libsanitizer/tsan/tsan_sync.h

   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 // These need to match __tsan_mutex_* flags defined in tsan_interface.h.
  25 // See documentation there as well.
  26 enum MutexFlags {
  27   MutexFlagLinkerInit          = 1 << 0, // __tsan_mutex_linker_init
  28   MutexFlagWriteReentrant      = 1 << 1, // __tsan_mutex_write_reentrant
  29   MutexFlagReadReentrant       = 1 << 2, // __tsan_mutex_read_reentrant
  30   MutexFlagReadLock            = 1 << 3, // __tsan_mutex_read_lock
  31   MutexFlagTryLock             = 1 << 4, // __tsan_mutex_try_lock
  32   MutexFlagTryLockFailed       = 1 << 5, // __tsan_mutex_try_lock_failed
  33   MutexFlagRecursiveLock       = 1 << 6, // __tsan_mutex_recursive_lock
  34   MutexFlagRecursiveUnlock     = 1 << 7, // __tsan_mutex_recursive_unlock
  35
  36   // The following flags are runtime private.
  37   // Mutex API misuse was detected, so don't report any more.
  38   MutexFlagBroken              = 1 << 30,
  39   // We did not intercept pre lock event, so handle it on post lock.
  40   MutexFlagDoPreLockOnPostLock = 1 << 29,
  41   // Must list all mutex creation flags.
  42   MutexCreationFlagMask        = MutexFlagLinkerInit |
  43                                  MutexFlagWriteReentrant |
  44                                  MutexFlagReadReentrant,
  45 };
  46
  47 struct SyncVar {
  48   SyncVar();
  49
  50   static const int kInvalidTid = -1;
  51
  52   uptr addr;  // overwritten by DenseSlabAlloc freelist
  53   Mutex mtx;
  54   u64 uid;  // Globally unique id.
  55   u32 creation_stack_id;
  56   int owner_tid;  // Set only by exclusive owners.
  57   u64 last_lock;
  58   int recursion;
  59   atomic_uint32_t flags;
  60   u32 next;  // in MetaMap
  61   DDMutex dd;
  62   SyncClock read_clock;  // Used for rw mutexes only.
  63   // The clock is placed last, so that it is situated on a different cache line
  64   // with the mtx. This reduces contention for hot sync objects.
  65   SyncClock clock;
  66
  67   void Init(ThreadState *thr, uptr pc, uptr addr, u64 uid);
  68   void Reset(Processor *proc);
  69
  70   u64 GetId() const {
  71     // 48 lsb is addr, then 14 bits is low part of uid, then 2 zero bits.
  72     return GetLsb((u64)addr | (uid << 48), 60);
  73   }
  74   bool CheckId(u64 uid) const {
  75     CHECK_EQ(uid, GetLsb(uid, 14));
  76     return GetLsb(this->uid, 14) == uid;
  77   }
  78   static uptr SplitId(u64 id, u64 *uid) {
  79     *uid = id >> 48;
  80     return (uptr)GetLsb(id, 48);
  81   }
  82
  83   bool IsFlagSet(u32 f) const {
  84     return atomic_load_relaxed(&flags) & f;
  85   }
  86
  87   void SetFlags(u32 f) {
  88     atomic_store_relaxed(&flags, atomic_load_relaxed(&flags) | f);
  89   }
  90
  91   void UpdateFlags(u32 flagz) {
  92     // Filter out operation flags.
  93     if (!(flagz & MutexCreationFlagMask))
  94       return;
  95     u32 current = atomic_load_relaxed(&flags);
  96     if (current & MutexCreationFlagMask)
  97       return;
  98     // Note: this can be called from MutexPostReadLock which holds only read
  99     // lock on the SyncVar.
 100     atomic_store_relaxed(&flags, current | (flagz & MutexCreationFlagMask));
 101   }
 102 };
 103
 104 /* MetaMap allows to map arbitrary user pointers onto various descriptors.
 105    Currently it maps pointers to heap block descriptors and sync var descs.
 106    It uses 1/2 direct shadow, see tsan_platform.h.
 107 */
 108 class MetaMap {
 109  public:
 110   MetaMap();
 111
 112   void AllocBlock(ThreadState *thr, uptr pc, uptr p, uptr sz);
 113   uptr FreeBlock(Processor *proc, uptr p);
 114   bool FreeRange(Processor *proc, uptr p, uptr sz);
 115   void ResetRange(Processor *proc, uptr p, uptr sz);
 116   MBlock* GetBlock(uptr p);
 117
 118   SyncVar* GetOrCreateAndLock(ThreadState *thr, uptr pc,
 119                               uptr addr, bool write_lock);
 120   SyncVar* GetIfExistsAndLock(uptr addr, bool write_lock);
 121
 122   void MoveMemory(uptr src, uptr dst, uptr sz);
 123
 124   void OnProcIdle(Processor *proc);
 125
 126  private:
 127   static const u32 kFlagMask  = 3u << 30;
 128   static const u32 kFlagBlock = 1u << 30;
 129   static const u32 kFlagSync  = 2u << 30;
 130   typedef DenseSlabAlloc<MBlock, 1<<16, 1<<12> BlockAlloc;
 131   typedef DenseSlabAlloc<SyncVar, 1<<16, 1<<10> SyncAlloc;
 132   BlockAlloc block_alloc_;
 133   SyncAlloc sync_alloc_;
 134   atomic_uint64_t uid_gen_;
 135
 136   SyncVar* GetAndLock(ThreadState *thr, uptr pc, uptr addr, bool write_lock,
 137                       bool create);
 138 };
 139
 140 }  // namespace __tsan
 141
 142 #endif  // TSAN_SYNC_H