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 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