src/compiler-rt/lib/tsan/rtl/tsan_mman.cc

   1 //===-- tsan_mman.cc ------------------------------------------------------===//
   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 //===----------------------------------------------------------------------===//
  13 #include "sanitizer_common/sanitizer_allocator_interface.h"
  14 #include "sanitizer_common/sanitizer_common.h"
  15 #include "sanitizer_common/sanitizer_placement_new.h"
  16 #include "tsan_mman.h"
  17 #include "tsan_rtl.h"
  18 #include "tsan_report.h"
  19 #include "tsan_flags.h"
  20
  21 // May be overriden by front-end.
  22 extern "C" void WEAK __sanitizer_malloc_hook(void *ptr, uptr size) {
  23   (void)ptr;
  24   (void)size;
  25 }
  26
  27 extern "C" void WEAK __sanitizer_free_hook(void *ptr) {
  28   (void)ptr;
  29 }
  30
  31 namespace __tsan {
  32
  33 struct MapUnmapCallback {
  34   void OnMap(uptr p, uptr size) const { }
  35   void OnUnmap(uptr p, uptr size) const {
  36     // We are about to unmap a chunk of user memory.
  37     // Mark the corresponding shadow memory as not needed.
  38     DontNeedShadowFor(p, size);
  39     // Mark the corresponding meta shadow memory as not needed.
  40     // Note the block does not contain any meta info at this point
  41     // (this happens after free).
  42     const uptr kMetaRatio = kMetaShadowCell / kMetaShadowSize;
  43     const uptr kPageSize = GetPageSizeCached() * kMetaRatio;
  44     // Block came from LargeMmapAllocator, so must be large.
  45     // We rely on this in the calculations below.
  46     CHECK_GE(size, 2 * kPageSize);
  47     uptr diff = RoundUp(p, kPageSize) - p;
  48     if (diff != 0) {
  49       p += diff;
  50       size -= diff;
  51     }
  52     diff = p + size - RoundDown(p + size, kPageSize);
  53     if (diff != 0)
  54       size -= diff;
  55     FlushUnneededShadowMemory((uptr)MemToMeta(p), size / kMetaRatio);
  56   }
  57 };
  58
  59 static char allocator_placeholder[sizeof(Allocator)] ALIGNED(64);
  60 Allocator *allocator() {
  61   return reinterpret_cast<Allocator*>(&allocator_placeholder);
  62 }
  63
  64 void InitializeAllocator() {
  65   allocator()->Init(common_flags()->allocator_may_return_null);
  66 }
  67
  68 void AllocatorThreadStart(ThreadState *thr) {
  69   allocator()->InitCache(&thr->alloc_cache);
  70   internal_allocator()->InitCache(&thr->internal_alloc_cache);
  71 }
  72
  73 void AllocatorThreadFinish(ThreadState *thr) {
  74   allocator()->DestroyCache(&thr->alloc_cache);
  75   internal_allocator()->DestroyCache(&thr->internal_alloc_cache);
  76 }
  77
  78 void AllocatorPrintStats() {
  79   allocator()->PrintStats();
  80 }
  81
  82 static void SignalUnsafeCall(ThreadState *thr, uptr pc) {
  83   if (atomic_load_relaxed(&thr->in_signal_handler) == 0 ||
  84       !flags()->report_signal_unsafe)
  85     return;
  86   VarSizeStackTrace stack;
  87   ObtainCurrentStack(thr, pc, &stack);
  88   if (IsFiredSuppression(ctx, ReportTypeSignalUnsafe, stack))
  89     return;
  90   ThreadRegistryLock l(ctx->thread_registry);
  91   ScopedReport rep(ReportTypeSignalUnsafe);
  92   rep.AddStack(stack, true);
  93   OutputReport(thr, rep);
  94 }
  95
  96 void *user_alloc(ThreadState *thr, uptr pc, uptr sz, uptr align, bool signal) {
  97   if ((sz >= (1ull << 40)) || (align >= (1ull << 40)))
  98     return allocator()->ReturnNullOrDie();
  99   void *p = allocator()->Allocate(&thr->alloc_cache, sz, align);
 100   if (p == 0)
 101     return 0;
 102   if (ctx && ctx->initialized)
 103     OnUserAlloc(thr, pc, (uptr)p, sz, true);
 104   if (signal)
 105     SignalUnsafeCall(thr, pc);
 106   return p;
 107 }
 108
 109 void *user_calloc(ThreadState *thr, uptr pc, uptr size, uptr n) {
 110   if (CallocShouldReturnNullDueToOverflow(size, n))
 111     return allocator()->ReturnNullOrDie();
 112   void *p = user_alloc(thr, pc, n * size);
 113   if (p)
 114     internal_memset(p, 0, n * size);
 115   return p;
 116 }
 117
 118 void user_free(ThreadState *thr, uptr pc, void *p, bool signal) {
 119   if (ctx && ctx->initialized)
 120     OnUserFree(thr, pc, (uptr)p, true);
 121   allocator()->Deallocate(&thr->alloc_cache, p);
 122   if (signal)
 123     SignalUnsafeCall(thr, pc);
 124 }
 125
 126 void OnUserAlloc(ThreadState *thr, uptr pc, uptr p, uptr sz, bool write) {
 127   DPrintf("#%d: alloc(%zu) = %p\n", thr->tid, sz, p);
 128   ctx->metamap.AllocBlock(thr, pc, p, sz);
 129   if (write && thr->ignore_reads_and_writes == 0)
 130     MemoryRangeImitateWrite(thr, pc, (uptr)p, sz);
 131   else
 132     MemoryResetRange(thr, pc, (uptr)p, sz);
 133 }
 134
 135 void OnUserFree(ThreadState *thr, uptr pc, uptr p, bool write) {
 136   CHECK_NE(p, (void*)0);
 137   uptr sz = ctx->metamap.FreeBlock(thr, pc, p);
 138   DPrintf("#%d: free(%p, %zu)\n", thr->tid, p, sz);
 139   if (write && thr->ignore_reads_and_writes == 0)
 140     MemoryRangeFreed(thr, pc, (uptr)p, sz);
 141 }
 142
 143 void *user_realloc(ThreadState *thr, uptr pc, void *p, uptr sz) {
 144   void *p2 = 0;
 145   // FIXME: Handle "shrinking" more efficiently,
 146   // it seems that some software actually does this.
 147   if (sz) {
 148     p2 = user_alloc(thr, pc, sz);
 149     if (p2 == 0)
 150       return 0;
 151     if (p) {
 152       uptr oldsz = user_alloc_usable_size(p);
 153       internal_memcpy(p2, p, min(oldsz, sz));
 154     }
 155   }
 156   if (p)
 157     user_free(thr, pc, p);
 158   return p2;
 159 }
 160
 161 uptr user_alloc_usable_size(const void *p) {
 162   if (p == 0)
 163     return 0;
 164   MBlock *b = ctx->metamap.GetBlock((uptr)p);
 165   return b ? b->siz : 0;
 166 }
 167
 168 void invoke_malloc_hook(void *ptr, uptr size) {
 169   ThreadState *thr = cur_thread();
 170   if (ctx == 0 || !ctx->initialized || thr->ignore_interceptors)
 171     return;
 172   __sanitizer_malloc_hook(ptr, size);
 173 }
 174
 175 void invoke_free_hook(void *ptr) {
 176   ThreadState *thr = cur_thread();
 177   if (ctx == 0 || !ctx->initialized || thr->ignore_interceptors)
 178     return;
 179   __sanitizer_free_hook(ptr);
 180 }
 181
 182 void *internal_alloc(MBlockType typ, uptr sz) {
 183   ThreadState *thr = cur_thread();
 184   if (thr->nomalloc) {
 185     thr->nomalloc = 0;  // CHECK calls internal_malloc().
 186     CHECK(0);
 187   }
 188   return InternalAlloc(sz, &thr->internal_alloc_cache);
 189 }
 190
 191 void internal_free(void *p) {
 192   ThreadState *thr = cur_thread();
 193   if (thr->nomalloc) {
 194     thr->nomalloc = 0;  // CHECK calls internal_malloc().
 195     CHECK(0);
 196   }
 197   InternalFree(p, &thr->internal_alloc_cache);
 198 }
 199
 200 }  // namespace __tsan
 201
 202 using namespace __tsan;
 203
 204 extern "C" {
 205 uptr __sanitizer_get_current_allocated_bytes() {
 206   uptr stats[AllocatorStatCount];
 207   allocator()->GetStats(stats);
 208   return stats[AllocatorStatAllocated];
 209 }
 210
 211 uptr __sanitizer_get_heap_size() {
 212   uptr stats[AllocatorStatCount];
 213   allocator()->GetStats(stats);
 214   return stats[AllocatorStatMapped];
 215 }
 216
 217 uptr __sanitizer_get_free_bytes() {
 218   return 1;
 219 }
 220
 221 uptr __sanitizer_get_unmapped_bytes() {
 222   return 1;
 223 }
 224
 225 uptr __sanitizer_get_estimated_allocated_size(uptr size) {
 226   return size;
 227 }
 228
 229 int __sanitizer_get_ownership(const void *p) {
 230   return allocator()->GetBlockBegin(p) != 0;
 231 }
 232
 233 uptr __sanitizer_get_allocated_size(const void *p) {
 234   return user_alloc_usable_size(p);
 235 }
 236
 237 void __tsan_on_thread_idle() {
 238   ThreadState *thr = cur_thread();
 239   allocator()->SwallowCache(&thr->alloc_cache);
 240   internal_allocator()->SwallowCache(&thr->internal_alloc_cache);
 241   ctx->metamap.OnThreadIdle(thr);
 242 }
 243 }  // extern "C"