1 //===-- tsan_rtl.h ----------------------------------------------*- C++ -*-===//
2 //
3 //                     The LLVM Compiler Infrastructure
4 //
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
7 //
8 //===----------------------------------------------------------------------===//
9 //
10 // This file is a part of ThreadSanitizer (TSan), a race detector.
11 //
12 // Main internal TSan header file.
13 //
14 // Ground rules:
15 //   - C++ run-time should not be used (static CTORs, RTTI, exceptions, static
16 //     function-scope locals)
17 //   - All functions/classes/etc reside in namespace __tsan, except for those
18 //     declared in tsan_interface.h.
19 //   - Platform-specific files should be used instead of ifdefs (*).
20 //   - No system headers included in header files (*).
21 //   - Platform specific headres included only into platform-specific files (*).
22 //
23 //  (*) Except when inlining is critical for performance.
24 //===----------------------------------------------------------------------===//
25 
26 #ifndef TSAN_RTL_H
27 #define TSAN_RTL_H
28 
29 #include "sanitizer_common/sanitizer_allocator.h"
30 #include "sanitizer_common/sanitizer_allocator_internal.h"
31 #include "sanitizer_common/sanitizer_asm.h"
32 #include "sanitizer_common/sanitizer_common.h"
33 #include "sanitizer_common/sanitizer_deadlock_detector_interface.h"
34 #include "sanitizer_common/sanitizer_libignore.h"
35 #include "sanitizer_common/sanitizer_suppressions.h"
36 #include "sanitizer_common/sanitizer_thread_registry.h"
37 #include "sanitizer_common/sanitizer_vector.h"
38 #include "tsan_clock.h"
39 #include "tsan_defs.h"
40 #include "tsan_flags.h"
41 #include "tsan_mman.h"
42 #include "tsan_sync.h"
43 #include "tsan_trace.h"
44 #include "tsan_report.h"
45 #include "tsan_platform.h"
46 #include "tsan_mutexset.h"
47 #include "tsan_ignoreset.h"
48 #include "tsan_stack_trace.h"
49 
50 #if SANITIZER_WORDSIZE != 64
51 # error "ThreadSanitizer is supported only on 64-bit platforms"
52 #endif
53 
54 namespace __tsan {
55 
56 #if !SANITIZER_GO
57 struct MapUnmapCallback;
58 #if defined(__mips64) || defined(__aarch64__) || defined(__powerpc__)
59 static const uptr kAllocatorRegionSizeLog = 20;
60 static const uptr kAllocatorNumRegions =
61     SANITIZER_MMAP_RANGE_SIZE >> kAllocatorRegionSizeLog;
62 using ByteMap = TwoLevelByteMap<(kAllocatorNumRegions >> 12), 1 << 12,
63                                 LocalAddressSpaceView, MapUnmapCallback>;
64 struct AP32 {
65   static const uptr kSpaceBeg = 0;
66   static const u64 kSpaceSize = SANITIZER_MMAP_RANGE_SIZE;
67   static const uptr kMetadataSize = 0;
68   typedef __sanitizer::CompactSizeClassMap SizeClassMap;
69   static const uptr kRegionSizeLog = kAllocatorRegionSizeLog;
70   using AddressSpaceView = LocalAddressSpaceView;
71   using ByteMap = __tsan::ByteMap;
72   typedef __tsan::MapUnmapCallback MapUnmapCallback;
73   static const uptr kFlags = 0;
74 };
75 typedef SizeClassAllocator32<AP32> PrimaryAllocator;
76 #else
77 struct AP64 {  // Allocator64 parameters. Deliberately using a short name.
78   static const uptr kSpaceBeg = Mapping::kHeapMemBeg;
79   static const uptr kSpaceSize = Mapping::kHeapMemEnd - Mapping::kHeapMemBeg;
80   static const uptr kMetadataSize = 0;
81   typedef DefaultSizeClassMap SizeClassMap;
82   typedef __tsan::MapUnmapCallback MapUnmapCallback;
83   static const uptr kFlags = 0;
84   using AddressSpaceView = LocalAddressSpaceView;
85 };
86 typedef SizeClassAllocator64<AP64> PrimaryAllocator;
87 #endif
88 typedef SizeClassAllocatorLocalCache<PrimaryAllocator> AllocatorCache;
89 typedef LargeMmapAllocator<MapUnmapCallback> SecondaryAllocator;
90 typedef CombinedAllocator<PrimaryAllocator, AllocatorCache,
91     SecondaryAllocator> Allocator;
92 Allocator *allocator();
93 #endif
94 
95 void TsanCheckFailed(const char *file, int line, const char *cond,
96                      u64 v1, u64 v2);
97 
98 const u64 kShadowRodata = (u64)-1;  // .rodata shadow marker
99 
100 // FastState (from most significant bit):
101 //   ignore          : 1
102 //   tid             : kTidBits
103 //   unused          : -
104 //   history_size    : 3
105 //   epoch           : kClkBits
106 class FastState {
107  public:
FastState(u64 tid,u64 epoch)108   FastState(u64 tid, u64 epoch) {
109     x_ = tid << kTidShift;
110     x_ |= epoch;
111     DCHECK_EQ(tid, this->tid());
112     DCHECK_EQ(epoch, this->epoch());
113     DCHECK_EQ(GetIgnoreBit(), false);
114   }
115 
FastState(u64 x)116   explicit FastState(u64 x)
117       : x_(x) {
118   }
119 
raw()120   u64 raw() const {
121     return x_;
122   }
123 
tid()124   u64 tid() const {
125     u64 res = (x_ & ~kIgnoreBit) >> kTidShift;
126     return res;
127   }
128 
TidWithIgnore()129   u64 TidWithIgnore() const {
130     u64 res = x_ >> kTidShift;
131     return res;
132   }
133 
epoch()134   u64 epoch() const {
135     u64 res = x_ & ((1ull << kClkBits) - 1);
136     return res;
137   }
138 
IncrementEpoch()139   void IncrementEpoch() {
140     u64 old_epoch = epoch();
141     x_ += 1;
142     DCHECK_EQ(old_epoch + 1, epoch());
143     (void)old_epoch;
144   }
145 
SetIgnoreBit()146   void SetIgnoreBit() { x_ |= kIgnoreBit; }
ClearIgnoreBit()147   void ClearIgnoreBit() { x_ &= ~kIgnoreBit; }
GetIgnoreBit()148   bool GetIgnoreBit() const { return (s64)x_ < 0; }
149 
SetHistorySize(int hs)150   void SetHistorySize(int hs) {
151     CHECK_GE(hs, 0);
152     CHECK_LE(hs, 7);
153     x_ = (x_ & ~(kHistoryMask << kHistoryShift)) | (u64(hs) << kHistoryShift);
154   }
155 
156   ALWAYS_INLINE
GetHistorySize()157   int GetHistorySize() const {
158     return (int)((x_ >> kHistoryShift) & kHistoryMask);
159   }
160 
ClearHistorySize()161   void ClearHistorySize() {
162     SetHistorySize(0);
163   }
164 
165   ALWAYS_INLINE
GetTracePos()166   u64 GetTracePos() const {
167     const int hs = GetHistorySize();
168     // When hs == 0, the trace consists of 2 parts.
169     const u64 mask = (1ull << (kTracePartSizeBits + hs + 1)) - 1;
170     return epoch() & mask;
171   }
172 
173  private:
174   friend class Shadow;
175   static const int kTidShift = 64 - kTidBits - 1;
176   static const u64 kIgnoreBit = 1ull << 63;
177   static const u64 kFreedBit = 1ull << 63;
178   static const u64 kHistoryShift = kClkBits;
179   static const u64 kHistoryMask = 7;
180   u64 x_;
181 };
182 
183 // Shadow (from most significant bit):
184 //   freed           : 1
185 //   tid             : kTidBits
186 //   is_atomic       : 1
187 //   is_read         : 1
188 //   size_log        : 2
189 //   addr0           : 3
190 //   epoch           : kClkBits
191 class Shadow : public FastState {
192  public:
Shadow(u64 x)193   explicit Shadow(u64 x)
194       : FastState(x) {
195   }
196 
Shadow(const FastState & s)197   explicit Shadow(const FastState &s)
198       : FastState(s.x_) {
199     ClearHistorySize();
200   }
201 
SetAddr0AndSizeLog(u64 addr0,unsigned kAccessSizeLog)202   void SetAddr0AndSizeLog(u64 addr0, unsigned kAccessSizeLog) {
203     DCHECK_EQ((x_ >> kClkBits) & 31, 0);
204     DCHECK_LE(addr0, 7);
205     DCHECK_LE(kAccessSizeLog, 3);
206     x_ |= ((kAccessSizeLog << 3) | addr0) << kClkBits;
207     DCHECK_EQ(kAccessSizeLog, size_log());
208     DCHECK_EQ(addr0, this->addr0());
209   }
210 
SetWrite(unsigned kAccessIsWrite)211   void SetWrite(unsigned kAccessIsWrite) {
212     DCHECK_EQ(x_ & kReadBit, 0);
213     if (!kAccessIsWrite)
214       x_ |= kReadBit;
215     DCHECK_EQ(kAccessIsWrite, IsWrite());
216   }
217 
SetAtomic(bool kIsAtomic)218   void SetAtomic(bool kIsAtomic) {
219     DCHECK(!IsAtomic());
220     if (kIsAtomic)
221       x_ |= kAtomicBit;
222     DCHECK_EQ(IsAtomic(), kIsAtomic);
223   }
224 
IsAtomic()225   bool IsAtomic() const {
226     return x_ & kAtomicBit;
227   }
228 
IsZero()229   bool IsZero() const {
230     return x_ == 0;
231   }
232 
TidsAreEqual(const Shadow s1,const Shadow s2)233   static inline bool TidsAreEqual(const Shadow s1, const Shadow s2) {
234     u64 shifted_xor = (s1.x_ ^ s2.x_) >> kTidShift;
235     DCHECK_EQ(shifted_xor == 0, s1.TidWithIgnore() == s2.TidWithIgnore());
236     return shifted_xor == 0;
237   }
238 
239   static ALWAYS_INLINE
Addr0AndSizeAreEqual(const Shadow s1,const Shadow s2)240   bool Addr0AndSizeAreEqual(const Shadow s1, const Shadow s2) {
241     u64 masked_xor = ((s1.x_ ^ s2.x_) >> kClkBits) & 31;
242     return masked_xor == 0;
243   }
244 
TwoRangesIntersect(Shadow s1,Shadow s2,unsigned kS2AccessSize)245   static ALWAYS_INLINE bool TwoRangesIntersect(Shadow s1, Shadow s2,
246       unsigned kS2AccessSize) {
247     bool res = false;
248     u64 diff = s1.addr0() - s2.addr0();
249     if ((s64)diff < 0) {  // s1.addr0 < s2.addr0  // NOLINT
250       // if (s1.addr0() + size1) > s2.addr0()) return true;
251       if (s1.size() > -diff)
252         res = true;
253     } else {
254       // if (s2.addr0() + kS2AccessSize > s1.addr0()) return true;
255       if (kS2AccessSize > diff)
256         res = true;
257     }
258     DCHECK_EQ(res, TwoRangesIntersectSlow(s1, s2));
259     DCHECK_EQ(res, TwoRangesIntersectSlow(s2, s1));
260     return res;
261   }
262 
addr0()263   u64 ALWAYS_INLINE addr0() const { return (x_ >> kClkBits) & 7; }
size()264   u64 ALWAYS_INLINE size() const { return 1ull << size_log(); }
IsWrite()265   bool ALWAYS_INLINE IsWrite() const { return !IsRead(); }
IsRead()266   bool ALWAYS_INLINE IsRead() const { return x_ & kReadBit; }
267 
268   // The idea behind the freed bit is as follows.
269   // When the memory is freed (or otherwise unaccessible) we write to the shadow
270   // values with tid/epoch related to the free and the freed bit set.
271   // During memory accesses processing the freed bit is considered
272   // as msb of tid. So any access races with shadow with freed bit set
273   // (it is as if write from a thread with which we never synchronized before).
274   // This allows us to detect accesses to freed memory w/o additional
275   // overheads in memory access processing and at the same time restore
276   // tid/epoch of free.
MarkAsFreed()277   void MarkAsFreed() {
278      x_ |= kFreedBit;
279   }
280 
IsFreed()281   bool IsFreed() const {
282     return x_ & kFreedBit;
283   }
284 
GetFreedAndReset()285   bool GetFreedAndReset() {
286     bool res = x_ & kFreedBit;
287     x_ &= ~kFreedBit;
288     return res;
289   }
290 
IsBothReadsOrAtomic(bool kIsWrite,bool kIsAtomic)291   bool ALWAYS_INLINE IsBothReadsOrAtomic(bool kIsWrite, bool kIsAtomic) const {
292     bool v = x_ & ((u64(kIsWrite ^ 1) << kReadShift)
293         | (u64(kIsAtomic) << kAtomicShift));
294     DCHECK_EQ(v, (!IsWrite() && !kIsWrite) || (IsAtomic() && kIsAtomic));
295     return v;
296   }
297 
IsRWNotWeaker(bool kIsWrite,bool kIsAtomic)298   bool ALWAYS_INLINE IsRWNotWeaker(bool kIsWrite, bool kIsAtomic) const {
299     bool v = ((x_ >> kReadShift) & 3)
300         <= u64((kIsWrite ^ 1) | (kIsAtomic << 1));
301     DCHECK_EQ(v, (IsAtomic() < kIsAtomic) ||
302         (IsAtomic() == kIsAtomic && !IsWrite() <= !kIsWrite));
303     return v;
304   }
305 
IsRWWeakerOrEqual(bool kIsWrite,bool kIsAtomic)306   bool ALWAYS_INLINE IsRWWeakerOrEqual(bool kIsWrite, bool kIsAtomic) const {
307     bool v = ((x_ >> kReadShift) & 3)
308         >= u64((kIsWrite ^ 1) | (kIsAtomic << 1));
309     DCHECK_EQ(v, (IsAtomic() > kIsAtomic) ||
310         (IsAtomic() == kIsAtomic && !IsWrite() >= !kIsWrite));
311     return v;
312   }
313 
314  private:
315   static const u64 kReadShift   = 5 + kClkBits;
316   static const u64 kReadBit     = 1ull << kReadShift;
317   static const u64 kAtomicShift = 6 + kClkBits;
318   static const u64 kAtomicBit   = 1ull << kAtomicShift;
319 
size_log()320   u64 size_log() const { return (x_ >> (3 + kClkBits)) & 3; }
321 
TwoRangesIntersectSlow(const Shadow s1,const Shadow s2)322   static bool TwoRangesIntersectSlow(const Shadow s1, const Shadow s2) {
323     if (s1.addr0() == s2.addr0()) return true;
324     if (s1.addr0() < s2.addr0() && s1.addr0() + s1.size() > s2.addr0())
325       return true;
326     if (s2.addr0() < s1.addr0() && s2.addr0() + s2.size() > s1.addr0())
327       return true;
328     return false;
329   }
330 };
331 
332 struct ThreadSignalContext;
333 
334 struct JmpBuf {
335   uptr sp;
336   uptr mangled_sp;
337   int int_signal_send;
338   bool in_blocking_func;
339   uptr in_signal_handler;
340   uptr *shadow_stack_pos;
341 };
342 
343 // A Processor represents a physical thread, or a P for Go.
344 // It is used to store internal resources like allocate cache, and does not
345 // participate in race-detection logic (invisible to end user).
346 // In C++ it is tied to an OS thread just like ThreadState, however ideally
347 // it should be tied to a CPU (this way we will have fewer allocator caches).
348 // In Go it is tied to a P, so there are significantly fewer Processor's than
349 // ThreadState's (which are tied to Gs).
350 // A ThreadState must be wired with a Processor to handle events.
351 struct Processor {
352   ThreadState *thr; // currently wired thread, or nullptr
353 #if !SANITIZER_GO
354   AllocatorCache alloc_cache;
355   InternalAllocatorCache internal_alloc_cache;
356 #endif
357   DenseSlabAllocCache block_cache;
358   DenseSlabAllocCache sync_cache;
359   DenseSlabAllocCache clock_cache;
360   DDPhysicalThread *dd_pt;
361 };
362 
363 #if !SANITIZER_GO
364 // ScopedGlobalProcessor temporary setups a global processor for the current
365 // thread, if it does not have one. Intended for interceptors that can run
366 // at the very thread end, when we already destroyed the thread processor.
367 struct ScopedGlobalProcessor {
368   ScopedGlobalProcessor();
369   ~ScopedGlobalProcessor();
370 };
371 #endif
372 
373 // This struct is stored in TLS.
374 struct ThreadState {
375   FastState fast_state;
376   // Synch epoch represents the threads's epoch before the last synchronization
377   // action. It allows to reduce number of shadow state updates.
378   // For example, fast_synch_epoch=100, last write to addr X was at epoch=150,
379   // if we are processing write to X from the same thread at epoch=200,
380   // we do nothing, because both writes happen in the same 'synch epoch'.
381   // That is, if another memory access does not race with the former write,
382   // it does not race with the latter as well.
383   // QUESTION: can we can squeeze this into ThreadState::Fast?
384   // E.g. ThreadState::Fast is a 44-bit, 32 are taken by synch_epoch and 12 are
385   // taken by epoch between synchs.
386   // This way we can save one load from tls.
387   u64 fast_synch_epoch;
388   // This is a slow path flag. On fast path, fast_state.GetIgnoreBit() is read.
389   // We do not distinguish beteween ignoring reads and writes
390   // for better performance.
391   int ignore_reads_and_writes;
392   int ignore_sync;
393   int suppress_reports;
394   // Go does not support ignores.
395 #if !SANITIZER_GO
396   IgnoreSet mop_ignore_set;
397   IgnoreSet sync_ignore_set;
398 #endif
399   // C/C++ uses fixed size shadow stack embed into Trace.
400   // Go uses malloc-allocated shadow stack with dynamic size.
401   uptr *shadow_stack;
402   uptr *shadow_stack_end;
403   uptr *shadow_stack_pos;
404   u64 *racy_shadow_addr;
405   u64 racy_state[2];
406   MutexSet mset;
407   ThreadClock clock;
408 #if !SANITIZER_GO
409   Vector<JmpBuf> jmp_bufs;
410   int ignore_interceptors;
411 #endif
412 #if TSAN_COLLECT_STATS
413   u64 stat[StatCnt];
414 #endif
415   const int tid;
416   const int unique_id;
417   bool in_symbolizer;
418   bool in_ignored_lib;
419   bool is_inited;
420   bool is_dead;
421   bool is_freeing;
422   bool is_vptr_access;
423   const uptr stk_addr;
424   const uptr stk_size;
425   const uptr tls_addr;
426   const uptr tls_size;
427   ThreadContext *tctx;
428 
429 #if SANITIZER_DEBUG && !SANITIZER_GO
430   InternalDeadlockDetector internal_deadlock_detector;
431 #endif
432   DDLogicalThread *dd_lt;
433 
434   // Current wired Processor, or nullptr. Required to handle any events.
435   Processor *proc1;
436 #if !SANITIZER_GO
procThreadState437   Processor *proc() { return proc1; }
438 #else
439   Processor *proc();
440 #endif
441 
442   atomic_uintptr_t in_signal_handler;
443   ThreadSignalContext *signal_ctx;
444 
445 #if !SANITIZER_GO
446   u32 last_sleep_stack_id;
447   ThreadClock last_sleep_clock;
448 #endif
449 
450   // Set in regions of runtime that must be signal-safe and fork-safe.
451   // If set, malloc must not be called.
452   int nomalloc;
453 
454   const ReportDesc *current_report;
455 
456   explicit ThreadState(Context *ctx, int tid, int unique_id, u64 epoch,
457                        unsigned reuse_count,
458                        uptr stk_addr, uptr stk_size,
459                        uptr tls_addr, uptr tls_size);
460 };
461 
462 #if !SANITIZER_GO
463 #if SANITIZER_MAC || SANITIZER_ANDROID
464 ThreadState *cur_thread();
465 void cur_thread_finalize();
466 #else
467 __attribute__((tls_model("initial-exec")))
468 extern THREADLOCAL char cur_thread_placeholder[];
cur_thread()469 INLINE ThreadState *cur_thread() {
470   return reinterpret_cast<ThreadState *>(&cur_thread_placeholder);
471 }
cur_thread_finalize()472 INLINE void cur_thread_finalize() { }
473 #endif  // SANITIZER_MAC || SANITIZER_ANDROID
474 #endif  // SANITIZER_GO
475 
476 class ThreadContext : public ThreadContextBase {
477  public:
478   explicit ThreadContext(int tid);
479   ~ThreadContext();
480   ThreadState *thr;
481   u32 creation_stack_id;
482   SyncClock sync;
483   // Epoch at which the thread had started.
484   // If we see an event from the thread stamped by an older epoch,
485   // the event is from a dead thread that shared tid with this thread.
486   u64 epoch0;
487   u64 epoch1;
488 
489   // Override superclass callbacks.
490   void OnDead() override;
491   void OnJoined(void *arg) override;
492   void OnFinished() override;
493   void OnStarted(void *arg) override;
494   void OnCreated(void *arg) override;
495   void OnReset() override;
496   void OnDetached(void *arg) override;
497 };
498 
499 struct RacyStacks {
500   MD5Hash hash[2];
501   bool operator==(const RacyStacks &other) const {
502     if (hash[0] == other.hash[0] && hash[1] == other.hash[1])
503       return true;
504     if (hash[0] == other.hash[1] && hash[1] == other.hash[0])
505       return true;
506     return false;
507   }
508 };
509 
510 struct RacyAddress {
511   uptr addr_min;
512   uptr addr_max;
513 };
514 
515 struct FiredSuppression {
516   ReportType type;
517   uptr pc_or_addr;
518   Suppression *supp;
519 };
520 
521 struct Context {
522   Context();
523 
524   bool initialized;
525 #if !SANITIZER_GO
526   bool after_multithreaded_fork;
527 #endif
528 
529   MetaMap metamap;
530 
531   Mutex report_mtx;
532   int nreported;
533   int nmissed_expected;
534   atomic_uint64_t last_symbolize_time_ns;
535 
536   void *background_thread;
537   atomic_uint32_t stop_background_thread;
538 
539   ThreadRegistry *thread_registry;
540 
541   Mutex racy_mtx;
542   Vector<RacyStacks> racy_stacks;
543   Vector<RacyAddress> racy_addresses;
544   // Number of fired suppressions may be large enough.
545   Mutex fired_suppressions_mtx;
546   InternalMmapVector<FiredSuppression> fired_suppressions;
547   DDetector *dd;
548 
549   ClockAlloc clock_alloc;
550 
551   Flags flags;
552 
553   u64 stat[StatCnt];
554   u64 int_alloc_cnt[MBlockTypeCount];
555   u64 int_alloc_siz[MBlockTypeCount];
556 };
557 
558 extern Context *ctx;  // The one and the only global runtime context.
559 
flags()560 ALWAYS_INLINE Flags *flags() {
561   return &ctx->flags;
562 }
563 
564 struct ScopedIgnoreInterceptors {
ScopedIgnoreInterceptorsScopedIgnoreInterceptors565   ScopedIgnoreInterceptors() {
566 #if !SANITIZER_GO
567     cur_thread()->ignore_interceptors++;
568 #endif
569   }
570 
~ScopedIgnoreInterceptorsScopedIgnoreInterceptors571   ~ScopedIgnoreInterceptors() {
572 #if !SANITIZER_GO
573     cur_thread()->ignore_interceptors--;
574 #endif
575   }
576 };
577 
578 const char *GetObjectTypeFromTag(uptr tag);
579 const char *GetReportHeaderFromTag(uptr tag);
580 uptr TagFromShadowStackFrame(uptr pc);
581 
582 class ScopedReportBase {
583  public:
584   void AddMemoryAccess(uptr addr, uptr external_tag, Shadow s, StackTrace stack,
585                        const MutexSet *mset);
586   void AddStack(StackTrace stack, bool suppressable = false);
587   void AddThread(const ThreadContext *tctx, bool suppressable = false);
588   void AddThread(int unique_tid, bool suppressable = false);
589   void AddUniqueTid(int unique_tid);
590   void AddMutex(const SyncVar *s);
591   u64 AddMutex(u64 id);
592   void AddLocation(uptr addr, uptr size);
593   void AddSleep(u32 stack_id);
594   void SetCount(int count);
595 
596   const ReportDesc *GetReport() const;
597 
598  protected:
599   ScopedReportBase(ReportType typ, uptr tag);
600   ~ScopedReportBase();
601 
602  private:
603   ReportDesc *rep_;
604   // Symbolizer makes lots of intercepted calls. If we try to process them,
605   // at best it will cause deadlocks on internal mutexes.
606   ScopedIgnoreInterceptors ignore_interceptors_;
607 
608   void AddDeadMutex(u64 id);
609 
610   ScopedReportBase(const ScopedReportBase &) = delete;
611   void operator=(const ScopedReportBase &) = delete;
612 };
613 
614 class ScopedReport : public ScopedReportBase {
615  public:
616   explicit ScopedReport(ReportType typ, uptr tag = kExternalTagNone);
617   ~ScopedReport();
618 
619  private:
620   ScopedErrorReportLock lock_;
621 };
622 
623 ThreadContext *IsThreadStackOrTls(uptr addr, bool *is_stack);
624 void RestoreStack(int tid, const u64 epoch, VarSizeStackTrace *stk,
625                   MutexSet *mset, uptr *tag = nullptr);
626 
627 // The stack could look like:
628 //   <start> | <main> | <foo> | tag | <bar>
629 // This will extract the tag and keep:
630 //   <start> | <main> | <foo> | <bar>
631 template<typename StackTraceTy>
632 void ExtractTagFromStack(StackTraceTy *stack, uptr *tag = nullptr) {
633   if (stack->size < 2) return;
634   uptr possible_tag_pc = stack->trace[stack->size - 2];
635   uptr possible_tag = TagFromShadowStackFrame(possible_tag_pc);
636   if (possible_tag == kExternalTagNone) return;
637   stack->trace_buffer[stack->size - 2] = stack->trace_buffer[stack->size - 1];
638   stack->size -= 1;
639   if (tag) *tag = possible_tag;
640 }
641 
642 template<typename StackTraceTy>
643 void ObtainCurrentStack(ThreadState *thr, uptr toppc, StackTraceTy *stack,
644                         uptr *tag = nullptr) {
645   uptr size = thr->shadow_stack_pos - thr->shadow_stack;
646   uptr start = 0;
647   if (size + !!toppc > kStackTraceMax) {
648     start = size + !!toppc - kStackTraceMax;
649     size = kStackTraceMax - !!toppc;
650   }
651   stack->Init(&thr->shadow_stack[start], size, toppc);
652   ExtractTagFromStack(stack, tag);
653 }
654 
655 #define GET_STACK_TRACE_FATAL(thr, pc) \
656   VarSizeStackTrace stack; \
657   ObtainCurrentStack(thr, pc, &stack); \
658   stack.ReverseOrder();
659 
660 #if TSAN_COLLECT_STATS
661 void StatAggregate(u64 *dst, u64 *src);
662 void StatOutput(u64 *stat);
663 #endif
664 
665 void ALWAYS_INLINE StatInc(ThreadState *thr, StatType typ, u64 n = 1) {
666 #if TSAN_COLLECT_STATS
667   thr->stat[typ] += n;
668 #endif
669 }
StatSet(ThreadState * thr,StatType typ,u64 n)670 void ALWAYS_INLINE StatSet(ThreadState *thr, StatType typ, u64 n) {
671 #if TSAN_COLLECT_STATS
672   thr->stat[typ] = n;
673 #endif
674 }
675 
676 void MapShadow(uptr addr, uptr size);
677 void MapThreadTrace(uptr addr, uptr size, const char *name);
678 void DontNeedShadowFor(uptr addr, uptr size);
679 void InitializeShadowMemory();
680 void InitializeInterceptors();
681 void InitializeLibIgnore();
682 void InitializeDynamicAnnotations();
683 
684 void ForkBefore(ThreadState *thr, uptr pc);
685 void ForkParentAfter(ThreadState *thr, uptr pc);
686 void ForkChildAfter(ThreadState *thr, uptr pc);
687 
688 void ReportRace(ThreadState *thr);
689 bool OutputReport(ThreadState *thr, const ScopedReport &srep);
690 bool IsFiredSuppression(Context *ctx, ReportType type, StackTrace trace);
691 bool IsExpectedReport(uptr addr, uptr size);
692 void PrintMatchedBenignRaces();
693 
694 #if defined(TSAN_DEBUG_OUTPUT) && TSAN_DEBUG_OUTPUT >= 1
695 # define DPrintf Printf
696 #else
697 # define DPrintf(...)
698 #endif
699 
700 #if defined(TSAN_DEBUG_OUTPUT) && TSAN_DEBUG_OUTPUT >= 2
701 # define DPrintf2 Printf
702 #else
703 # define DPrintf2(...)
704 #endif
705 
706 u32 CurrentStackId(ThreadState *thr, uptr pc);
707 ReportStack *SymbolizeStackId(u32 stack_id);
708 void PrintCurrentStack(ThreadState *thr, uptr pc);
709 void PrintCurrentStackSlow(uptr pc);  // uses libunwind
710 
711 void Initialize(ThreadState *thr);
712 void MaybeSpawnBackgroundThread();
713 int Finalize(ThreadState *thr);
714 
715 void OnUserAlloc(ThreadState *thr, uptr pc, uptr p, uptr sz, bool write);
716 void OnUserFree(ThreadState *thr, uptr pc, uptr p, bool write);
717 
718 void MemoryAccess(ThreadState *thr, uptr pc, uptr addr,
719     int kAccessSizeLog, bool kAccessIsWrite, bool kIsAtomic);
720 void MemoryAccessImpl(ThreadState *thr, uptr addr,
721     int kAccessSizeLog, bool kAccessIsWrite, bool kIsAtomic,
722     u64 *shadow_mem, Shadow cur);
723 void MemoryAccessRange(ThreadState *thr, uptr pc, uptr addr,
724     uptr size, bool is_write);
725 void MemoryAccessRangeStep(ThreadState *thr, uptr pc, uptr addr,
726     uptr size, uptr step, bool is_write);
727 void UnalignedMemoryAccess(ThreadState *thr, uptr pc, uptr addr,
728     int size, bool kAccessIsWrite, bool kIsAtomic);
729 
730 const int kSizeLog1 = 0;
731 const int kSizeLog2 = 1;
732 const int kSizeLog4 = 2;
733 const int kSizeLog8 = 3;
734 
MemoryRead(ThreadState * thr,uptr pc,uptr addr,int kAccessSizeLog)735 void ALWAYS_INLINE MemoryRead(ThreadState *thr, uptr pc,
736                                      uptr addr, int kAccessSizeLog) {
737   MemoryAccess(thr, pc, addr, kAccessSizeLog, false, false);
738 }
739 
MemoryWrite(ThreadState * thr,uptr pc,uptr addr,int kAccessSizeLog)740 void ALWAYS_INLINE MemoryWrite(ThreadState *thr, uptr pc,
741                                       uptr addr, int kAccessSizeLog) {
742   MemoryAccess(thr, pc, addr, kAccessSizeLog, true, false);
743 }
744 
MemoryReadAtomic(ThreadState * thr,uptr pc,uptr addr,int kAccessSizeLog)745 void ALWAYS_INLINE MemoryReadAtomic(ThreadState *thr, uptr pc,
746                                            uptr addr, int kAccessSizeLog) {
747   MemoryAccess(thr, pc, addr, kAccessSizeLog, false, true);
748 }
749 
MemoryWriteAtomic(ThreadState * thr,uptr pc,uptr addr,int kAccessSizeLog)750 void ALWAYS_INLINE MemoryWriteAtomic(ThreadState *thr, uptr pc,
751                                             uptr addr, int kAccessSizeLog) {
752   MemoryAccess(thr, pc, addr, kAccessSizeLog, true, true);
753 }
754 
755 void MemoryResetRange(ThreadState *thr, uptr pc, uptr addr, uptr size);
756 void MemoryRangeFreed(ThreadState *thr, uptr pc, uptr addr, uptr size);
757 void MemoryRangeImitateWrite(ThreadState *thr, uptr pc, uptr addr, uptr size);
758 
759 void ThreadIgnoreBegin(ThreadState *thr, uptr pc, bool save_stack = true);
760 void ThreadIgnoreEnd(ThreadState *thr, uptr pc);
761 void ThreadIgnoreSyncBegin(ThreadState *thr, uptr pc, bool save_stack = true);
762 void ThreadIgnoreSyncEnd(ThreadState *thr, uptr pc);
763 
764 void FuncEntry(ThreadState *thr, uptr pc);
765 void FuncExit(ThreadState *thr);
766 
767 int ThreadCreate(ThreadState *thr, uptr pc, uptr uid, bool detached);
768 void ThreadStart(ThreadState *thr, int tid, tid_t os_id, bool workerthread);
769 void ThreadFinish(ThreadState *thr);
770 int ThreadTid(ThreadState *thr, uptr pc, uptr uid);
771 void ThreadJoin(ThreadState *thr, uptr pc, int tid);
772 void ThreadDetach(ThreadState *thr, uptr pc, int tid);
773 void ThreadFinalize(ThreadState *thr);
774 void ThreadSetName(ThreadState *thr, const char *name);
775 int ThreadCount(ThreadState *thr);
776 void ProcessPendingSignals(ThreadState *thr);
777 void ThreadNotJoined(ThreadState *thr, uptr pc, int tid, uptr uid);
778 
779 Processor *ProcCreate();
780 void ProcDestroy(Processor *proc);
781 void ProcWire(Processor *proc, ThreadState *thr);
782 void ProcUnwire(Processor *proc, ThreadState *thr);
783 
784 // Note: the parameter is called flagz, because flags is already taken
785 // by the global function that returns flags.
786 void MutexCreate(ThreadState *thr, uptr pc, uptr addr, u32 flagz = 0);
787 void MutexDestroy(ThreadState *thr, uptr pc, uptr addr, u32 flagz = 0);
788 void MutexPreLock(ThreadState *thr, uptr pc, uptr addr, u32 flagz = 0);
789 void MutexPostLock(ThreadState *thr, uptr pc, uptr addr, u32 flagz = 0,
790     int rec = 1);
791 int  MutexUnlock(ThreadState *thr, uptr pc, uptr addr, u32 flagz = 0);
792 void MutexPreReadLock(ThreadState *thr, uptr pc, uptr addr, u32 flagz = 0);
793 void MutexPostReadLock(ThreadState *thr, uptr pc, uptr addr, u32 flagz = 0);
794 void MutexReadUnlock(ThreadState *thr, uptr pc, uptr addr);
795 void MutexReadOrWriteUnlock(ThreadState *thr, uptr pc, uptr addr);
796 void MutexRepair(ThreadState *thr, uptr pc, uptr addr);  // call on EOWNERDEAD
797 void MutexInvalidAccess(ThreadState *thr, uptr pc, uptr addr);
798 
799 void Acquire(ThreadState *thr, uptr pc, uptr addr);
800 // AcquireGlobal synchronizes the current thread with all other threads.
801 // In terms of happens-before relation, it draws a HB edge from all threads
802 // (where they happen to execute right now) to the current thread. We use it to
803 // handle Go finalizers. Namely, finalizer goroutine executes AcquireGlobal
804 // right before executing finalizers. This provides a coarse, but simple
805 // approximation of the actual required synchronization.
806 void AcquireGlobal(ThreadState *thr, uptr pc);
807 void Release(ThreadState *thr, uptr pc, uptr addr);
808 void ReleaseStore(ThreadState *thr, uptr pc, uptr addr);
809 void AfterSleep(ThreadState *thr, uptr pc);
810 void AcquireImpl(ThreadState *thr, uptr pc, SyncClock *c);
811 void ReleaseImpl(ThreadState *thr, uptr pc, SyncClock *c);
812 void ReleaseStoreImpl(ThreadState *thr, uptr pc, SyncClock *c);
813 void AcquireReleaseImpl(ThreadState *thr, uptr pc, SyncClock *c);
814 
815 // The hacky call uses custom calling convention and an assembly thunk.
816 // It is considerably faster that a normal call for the caller
817 // if it is not executed (it is intended for slow paths from hot functions).
818 // The trick is that the call preserves all registers and the compiler
819 // does not treat it as a call.
820 // If it does not work for you, use normal call.
821 #if !SANITIZER_DEBUG && defined(__x86_64__) && !SANITIZER_MAC
822 // The caller may not create the stack frame for itself at all,
823 // so we create a reserve stack frame for it (1024b must be enough).
824 #define HACKY_CALL(f) \
825   __asm__ __volatile__("sub $1024, %%rsp;" \
826                        CFI_INL_ADJUST_CFA_OFFSET(1024) \
827                        ".hidden " #f "_thunk;" \
828                        "call " #f "_thunk;" \
829                        "add $1024, %%rsp;" \
830                        CFI_INL_ADJUST_CFA_OFFSET(-1024) \
831                        ::: "memory", "cc");
832 #else
833 #define HACKY_CALL(f) f()
834 #endif
835 
836 void TraceSwitch(ThreadState *thr);
837 uptr TraceTopPC(ThreadState *thr);
838 uptr TraceSize();
839 uptr TraceParts();
840 Trace *ThreadTrace(int tid);
841 
842 extern "C" void __tsan_trace_switch();
TraceAddEvent(ThreadState * thr,FastState fs,EventType typ,u64 addr)843 void ALWAYS_INLINE TraceAddEvent(ThreadState *thr, FastState fs,
844                                         EventType typ, u64 addr) {
845   if (!kCollectHistory)
846     return;
847   DCHECK_GE((int)typ, 0);
848   DCHECK_LE((int)typ, 7);
849   DCHECK_EQ(GetLsb(addr, kEventPCBits), addr);
850   StatInc(thr, StatEvents);
851   u64 pos = fs.GetTracePos();
852   if (UNLIKELY((pos % kTracePartSize) == 0)) {
853 #if !SANITIZER_GO
854     HACKY_CALL(__tsan_trace_switch);
855 #else
856     TraceSwitch(thr);
857 #endif
858   }
859   Event *trace = (Event*)GetThreadTrace(fs.tid());
860   Event *evp = &trace[pos];
861   Event ev = (u64)addr | ((u64)typ << kEventPCBits);
862   *evp = ev;
863 }
864 
865 #if !SANITIZER_GO
HeapEnd()866 uptr ALWAYS_INLINE HeapEnd() {
867   return HeapMemEnd() + PrimaryAllocator::AdditionalSize();
868 }
869 #endif
870 
871 }  // namespace __tsan
872 
873 #endif  // TSAN_RTL_H
874