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_common.h" 14 #include "sanitizer_common/sanitizer_placement_new.h" 15 #include "tsan_mman.h" 16 #include "tsan_rtl.h" 17 #include "tsan_report.h" 18 #include "tsan_flags.h" 19 20 // May be overriden by front-end. 21 extern "C" void WEAK __tsan_malloc_hook(void *ptr, uptr size) { 22 (void)ptr; 23 (void)size; 24 } 25 26 extern "C" void WEAK __tsan_free_hook(void *ptr) { 27 (void)ptr; 28 } 29 30 namespace __tsan { 31 32 COMPILER_CHECK(sizeof(MBlock) == 16); 33 34 void MBlock::Lock() { 35 atomic_uintptr_t *a = reinterpret_cast<atomic_uintptr_t*>(this); 36 uptr v = atomic_load(a, memory_order_relaxed); 37 for (int iter = 0;; iter++) { 38 if (v & 1) { 39 if (iter < 10) 40 proc_yield(20); 41 else 42 internal_sched_yield(); 43 v = atomic_load(a, memory_order_relaxed); 44 continue; 45 } 46 if (atomic_compare_exchange_weak(a, &v, v | 1, memory_order_acquire)) 47 break; 48 } 49 } 50 51 void MBlock::Unlock() { 52 atomic_uintptr_t *a = reinterpret_cast<atomic_uintptr_t*>(this); 53 uptr v = atomic_load(a, memory_order_relaxed); 54 DCHECK(v & 1); 55 atomic_store(a, v & ~1, memory_order_relaxed); 56 } 57 58 struct MapUnmapCallback { 59 void OnMap(uptr p, uptr size) const { } 60 void OnUnmap(uptr p, uptr size) const { 61 // We are about to unmap a chunk of user memory. 62 // Mark the corresponding shadow memory as not needed. 63 DontNeedShadowFor(p, size); 64 } 65 }; 66 67 static char allocator_placeholder[sizeof(Allocator)] ALIGNED(64); 68 Allocator *allocator() { 69 return reinterpret_cast<Allocator*>(&allocator_placeholder); 70 } 71 72 void InitializeAllocator() { 73 allocator()->Init(); 74 } 75 76 void AllocatorThreadStart(ThreadState *thr) { 77 allocator()->InitCache(&thr->alloc_cache); 78 internal_allocator()->InitCache(&thr->internal_alloc_cache); 79 } 80 81 void AllocatorThreadFinish(ThreadState *thr) { 82 allocator()->DestroyCache(&thr->alloc_cache); 83 internal_allocator()->DestroyCache(&thr->internal_alloc_cache); 84 } 85 86 void AllocatorPrintStats() { 87 allocator()->PrintStats(); 88 } 89 90 static void SignalUnsafeCall(ThreadState *thr, uptr pc) { 91 if (!thr->in_signal_handler || !flags()->report_signal_unsafe) 92 return; 93 Context *ctx = CTX(); 94 StackTrace stack; 95 stack.ObtainCurrent(thr, pc); 96 ThreadRegistryLock l(ctx->thread_registry); 97 ScopedReport rep(ReportTypeSignalUnsafe); 98 if (!IsFiredSuppression(ctx, rep, stack)) { 99 rep.AddStack(&stack); 100 OutputReport(ctx, rep, rep.GetReport()->stacks[0]); 101 } 102 } 103 104 void *user_alloc(ThreadState *thr, uptr pc, uptr sz, uptr align) { 105 CHECK_GT(thr->in_rtl, 0); 106 if ((sz >= (1ull << 40)) || (align >= (1ull << 40))) 107 return 0; 108 void *p = allocator()->Allocate(&thr->alloc_cache, sz, align); 109 if (p == 0) 110 return 0; 111 MBlock *b = new(allocator()->GetMetaData(p)) MBlock; 112 b->Init(sz, thr->tid, CurrentStackId(thr, pc)); 113 if (CTX() && CTX()->initialized) 114 MemoryRangeImitateWrite(thr, pc, (uptr)p, sz); 115 DPrintf("#%d: alloc(%zu) = %p\n", thr->tid, sz, p); 116 SignalUnsafeCall(thr, pc); 117 return p; 118 } 119 120 void user_free(ThreadState *thr, uptr pc, void *p) { 121 CHECK_GT(thr->in_rtl, 0); 122 CHECK_NE(p, (void*)0); 123 DPrintf("#%d: free(%p)\n", thr->tid, p); 124 MBlock *b = (MBlock*)allocator()->GetMetaData(p); 125 if (b->ListHead()) { 126 MBlock::ScopedLock l(b); 127 for (SyncVar *s = b->ListHead(); s;) { 128 SyncVar *res = s; 129 s = s->next; 130 StatInc(thr, StatSyncDestroyed); 131 res->mtx.Lock(); 132 res->mtx.Unlock(); 133 DestroyAndFree(res); 134 } 135 b->ListReset(); 136 } 137 if (CTX() && CTX()->initialized && thr->in_rtl == 1) 138 MemoryRangeFreed(thr, pc, (uptr)p, b->Size()); 139 allocator()->Deallocate(&thr->alloc_cache, p); 140 SignalUnsafeCall(thr, pc); 141 } 142 143 void *user_realloc(ThreadState *thr, uptr pc, void *p, uptr sz) { 144 CHECK_GT(thr->in_rtl, 0); 145 void *p2 = 0; 146 // FIXME: Handle "shrinking" more efficiently, 147 // it seems that some software actually does this. 148 if (sz) { 149 p2 = user_alloc(thr, pc, sz); 150 if (p2 == 0) 151 return 0; 152 if (p) { 153 MBlock *b = user_mblock(thr, p); 154 CHECK_NE(b, 0); 155 internal_memcpy(p2, p, min(b->Size(), sz)); 156 } 157 } 158 if (p) 159 user_free(thr, pc, p); 160 return p2; 161 } 162 163 uptr user_alloc_usable_size(ThreadState *thr, uptr pc, void *p) { 164 CHECK_GT(thr->in_rtl, 0); 165 if (p == 0) 166 return 0; 167 MBlock *b = (MBlock*)allocator()->GetMetaData(p); 168 return b ? b->Size() : 0; 169 } 170 171 MBlock *user_mblock(ThreadState *thr, void *p) { 172 CHECK_NE(p, 0); 173 Allocator *a = allocator(); 174 void *b = a->GetBlockBegin(p); 175 if (b == 0) 176 return 0; 177 return (MBlock*)a->GetMetaData(b); 178 } 179 180 void invoke_malloc_hook(void *ptr, uptr size) { 181 Context *ctx = CTX(); 182 ThreadState *thr = cur_thread(); 183 if (ctx == 0 || !ctx->initialized || thr->in_rtl) 184 return; 185 __tsan_malloc_hook(ptr, size); 186 } 187 188 void invoke_free_hook(void *ptr) { 189 Context *ctx = CTX(); 190 ThreadState *thr = cur_thread(); 191 if (ctx == 0 || !ctx->initialized || thr->in_rtl) 192 return; 193 __tsan_free_hook(ptr); 194 } 195 196 void *internal_alloc(MBlockType typ, uptr sz) { 197 ThreadState *thr = cur_thread(); 198 CHECK_GT(thr->in_rtl, 0); 199 CHECK_LE(sz, InternalSizeClassMap::kMaxSize); 200 if (thr->nomalloc) { 201 thr->nomalloc = 0; // CHECK calls internal_malloc(). 202 CHECK(0); 203 } 204 return InternalAlloc(sz, &thr->internal_alloc_cache); 205 } 206 207 void internal_free(void *p) { 208 ThreadState *thr = cur_thread(); 209 CHECK_GT(thr->in_rtl, 0); 210 if (thr->nomalloc) { 211 thr->nomalloc = 0; // CHECK calls internal_malloc(). 212 CHECK(0); 213 } 214 InternalFree(p, &thr->internal_alloc_cache); 215 } 216 217 } // namespace __tsan 218 219 using namespace __tsan; 220 221 extern "C" { 222 uptr __tsan_get_current_allocated_bytes() { 223 u64 stats[AllocatorStatCount]; 224 allocator()->GetStats(stats); 225 u64 m = stats[AllocatorStatMalloced]; 226 u64 f = stats[AllocatorStatFreed]; 227 return m >= f ? m - f : 1; 228 } 229 230 uptr __tsan_get_heap_size() { 231 u64 stats[AllocatorStatCount]; 232 allocator()->GetStats(stats); 233 u64 m = stats[AllocatorStatMmapped]; 234 u64 f = stats[AllocatorStatUnmapped]; 235 return m >= f ? m - f : 1; 236 } 237 238 uptr __tsan_get_free_bytes() { 239 return 1; 240 } 241 242 uptr __tsan_get_unmapped_bytes() { 243 return 1; 244 } 245 246 uptr __tsan_get_estimated_allocated_size(uptr size) { 247 return size; 248 } 249 250 bool __tsan_get_ownership(void *p) { 251 return allocator()->GetBlockBegin(p) != 0; 252 } 253 254 uptr __tsan_get_allocated_size(void *p) { 255 if (p == 0) 256 return 0; 257 p = allocator()->GetBlockBegin(p); 258 if (p == 0) 259 return 0; 260 MBlock *b = (MBlock*)allocator()->GetMetaData(p); 261 return b->Size(); 262 } 263 264 void __tsan_on_thread_idle() { 265 ThreadState *thr = cur_thread(); 266 allocator()->SwallowCache(&thr->alloc_cache); 267 internal_allocator()->SwallowCache(&thr->internal_alloc_cache); 268 } 269 } // extern "C" 270
