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Diffstat (limited to 'contrib/compiler-rt/lib/tsan/rtl/tsan_rtl.cc')
| -rw-r--r-- | contrib/compiler-rt/lib/tsan/rtl/tsan_rtl.cc | 1020 |
1 files changed, 1020 insertions, 0 deletions
diff --git a/contrib/compiler-rt/lib/tsan/rtl/tsan_rtl.cc b/contrib/compiler-rt/lib/tsan/rtl/tsan_rtl.cc new file mode 100644 index 0000000..7cb7008 --- /dev/null +++ b/contrib/compiler-rt/lib/tsan/rtl/tsan_rtl.cc @@ -0,0 +1,1020 @@ +//===-- tsan_rtl.cc -------------------------------------------------------===// +// +// The LLVM Compiler Infrastructure +// +// This file is distributed under the University of Illinois Open Source +// License. See LICENSE.TXT for details. +// +//===----------------------------------------------------------------------===// +// +// This file is a part of ThreadSanitizer (TSan), a race detector. +// +// Main file (entry points) for the TSan run-time. +//===----------------------------------------------------------------------===// + +#include "sanitizer_common/sanitizer_atomic.h" +#include "sanitizer_common/sanitizer_common.h" +#include "sanitizer_common/sanitizer_libc.h" +#include "sanitizer_common/sanitizer_stackdepot.h" +#include "sanitizer_common/sanitizer_placement_new.h" +#include "sanitizer_common/sanitizer_symbolizer.h" +#include "tsan_defs.h" +#include "tsan_platform.h" +#include "tsan_rtl.h" +#include "tsan_mman.h" +#include "tsan_suppressions.h" +#include "tsan_symbolize.h" + +#ifdef __SSE3__ +// <emmintrin.h> transitively includes <stdlib.h>, +// and it's prohibited to include std headers into tsan runtime. +// So we do this dirty trick. +#define _MM_MALLOC_H_INCLUDED +#define __MM_MALLOC_H +#include <emmintrin.h> +typedef __m128i m128; +#endif + +volatile int __tsan_resumed = 0; + +extern "C" void __tsan_resume() { + __tsan_resumed = 1; +} + +namespace __tsan { + +#ifndef SANITIZER_GO +THREADLOCAL char cur_thread_placeholder[sizeof(ThreadState)] ALIGNED(64); +#endif +static char ctx_placeholder[sizeof(Context)] ALIGNED(64); +Context *ctx; + +// Can be overriden by a front-end. +#ifdef TSAN_EXTERNAL_HOOKS +bool OnFinalize(bool failed); +void OnInitialize(); +#else +SANITIZER_INTERFACE_ATTRIBUTE +bool WEAK OnFinalize(bool failed) { + return failed; +} +SANITIZER_INTERFACE_ATTRIBUTE +void WEAK OnInitialize() {} +#endif + +static char thread_registry_placeholder[sizeof(ThreadRegistry)]; + +static ThreadContextBase *CreateThreadContext(u32 tid) { + // Map thread trace when context is created. + MapThreadTrace(GetThreadTrace(tid), TraceSize() * sizeof(Event)); + MapThreadTrace(GetThreadTraceHeader(tid), sizeof(Trace)); + new(ThreadTrace(tid)) Trace(); + void *mem = internal_alloc(MBlockThreadContex, sizeof(ThreadContext)); + return new(mem) ThreadContext(tid); +} + +#ifndef SANITIZER_GO +static const u32 kThreadQuarantineSize = 16; +#else +static const u32 kThreadQuarantineSize = 64; +#endif + +Context::Context() + : initialized() + , report_mtx(MutexTypeReport, StatMtxReport) + , nreported() + , nmissed_expected() + , thread_registry(new(thread_registry_placeholder) ThreadRegistry( + CreateThreadContext, kMaxTid, kThreadQuarantineSize, kMaxTidReuse)) + , racy_stacks(MBlockRacyStacks) + , racy_addresses(MBlockRacyAddresses) + , fired_suppressions(8) { +} + +// The objects are allocated in TLS, so one may rely on zero-initialization. +ThreadState::ThreadState(Context *ctx, int tid, int unique_id, u64 epoch, + unsigned reuse_count, + uptr stk_addr, uptr stk_size, + uptr tls_addr, uptr tls_size) + : fast_state(tid, epoch) + // Do not touch these, rely on zero initialization, + // they may be accessed before the ctor. + // , ignore_reads_and_writes() + // , ignore_interceptors() + , clock(tid, reuse_count) +#ifndef SANITIZER_GO + , jmp_bufs(MBlockJmpBuf) +#endif + , tid(tid) + , unique_id(unique_id) + , stk_addr(stk_addr) + , stk_size(stk_size) + , tls_addr(tls_addr) + , tls_size(tls_size) +#ifndef SANITIZER_GO + , last_sleep_clock(tid) +#endif +{ +} + +static void MemoryProfiler(Context *ctx, fd_t fd, int i) { + uptr n_threads; + uptr n_running_threads; + ctx->thread_registry->GetNumberOfThreads(&n_threads, &n_running_threads); + InternalScopedBuffer<char> buf(4096); + WriteMemoryProfile(buf.data(), buf.size(), n_threads, n_running_threads); + internal_write(fd, buf.data(), internal_strlen(buf.data())); +} + +static void BackgroundThread(void *arg) { +#ifndef SANITIZER_GO + // This is a non-initialized non-user thread, nothing to see here. + // We don't use ScopedIgnoreInterceptors, because we want ignores to be + // enabled even when the thread function exits (e.g. during pthread thread + // shutdown code). + cur_thread()->ignore_interceptors++; +#endif + const u64 kMs2Ns = 1000 * 1000; + + fd_t mprof_fd = kInvalidFd; + if (flags()->profile_memory && flags()->profile_memory[0]) { + if (internal_strcmp(flags()->profile_memory, "stdout") == 0) { + mprof_fd = 1; + } else if (internal_strcmp(flags()->profile_memory, "stderr") == 0) { + mprof_fd = 2; + } else { + InternalScopedString filename(kMaxPathLength); + filename.append("%s.%d", flags()->profile_memory, (int)internal_getpid()); + uptr openrv = OpenFile(filename.data(), true); + if (internal_iserror(openrv)) { + Printf("ThreadSanitizer: failed to open memory profile file '%s'\n", + &filename[0]); + } else { + mprof_fd = openrv; + } + } + } + + u64 last_flush = NanoTime(); + uptr last_rss = 0; + for (int i = 0; + atomic_load(&ctx->stop_background_thread, memory_order_relaxed) == 0; + i++) { + SleepForMillis(100); + u64 now = NanoTime(); + + // Flush memory if requested. + if (flags()->flush_memory_ms > 0) { + if (last_flush + flags()->flush_memory_ms * kMs2Ns < now) { + VPrintf(1, "ThreadSanitizer: periodic memory flush\n"); + FlushShadowMemory(); + last_flush = NanoTime(); + } + } + // GetRSS can be expensive on huge programs, so don't do it every 100ms. + if (flags()->memory_limit_mb > 0) { + uptr rss = GetRSS(); + uptr limit = uptr(flags()->memory_limit_mb) << 20; + VPrintf(1, "ThreadSanitizer: memory flush check" + " RSS=%llu LAST=%llu LIMIT=%llu\n", + (u64)rss >> 20, (u64)last_rss >> 20, (u64)limit >> 20); + if (2 * rss > limit + last_rss) { + VPrintf(1, "ThreadSanitizer: flushing memory due to RSS\n"); + FlushShadowMemory(); + rss = GetRSS(); + VPrintf(1, "ThreadSanitizer: memory flushed RSS=%llu\n", (u64)rss>>20); + } + last_rss = rss; + } + + // Write memory profile if requested. + if (mprof_fd != kInvalidFd) + MemoryProfiler(ctx, mprof_fd, i); + +#ifndef SANITIZER_GO + // Flush symbolizer cache if requested. + if (flags()->flush_symbolizer_ms > 0) { + u64 last = atomic_load(&ctx->last_symbolize_time_ns, + memory_order_relaxed); + if (last != 0 && last + flags()->flush_symbolizer_ms * kMs2Ns < now) { + Lock l(&ctx->report_mtx); + SpinMutexLock l2(&CommonSanitizerReportMutex); + SymbolizeFlush(); + atomic_store(&ctx->last_symbolize_time_ns, 0, memory_order_relaxed); + } + } +#endif + } +} + +static void StartBackgroundThread() { + ctx->background_thread = internal_start_thread(&BackgroundThread, 0); +} + +#ifndef SANITIZER_GO +static void StopBackgroundThread() { + atomic_store(&ctx->stop_background_thread, 1, memory_order_relaxed); + internal_join_thread(ctx->background_thread); + ctx->background_thread = 0; +} +#endif + +void DontNeedShadowFor(uptr addr, uptr size) { + uptr shadow_beg = MemToShadow(addr); + uptr shadow_end = MemToShadow(addr + size); + FlushUnneededShadowMemory(shadow_beg, shadow_end - shadow_beg); +} + +void MapShadow(uptr addr, uptr size) { + // Global data is not 64K aligned, but there are no adjacent mappings, + // so we can get away with unaligned mapping. + // CHECK_EQ(addr, addr & ~((64 << 10) - 1)); // windows wants 64K alignment + MmapFixedNoReserve(MemToShadow(addr), size * kShadowMultiplier); + + // Meta shadow is 2:1, so tread carefully. + static bool data_mapped = false; + static uptr mapped_meta_end = 0; + uptr meta_begin = (uptr)MemToMeta(addr); + uptr meta_end = (uptr)MemToMeta(addr + size); + meta_begin = RoundDownTo(meta_begin, 64 << 10); + meta_end = RoundUpTo(meta_end, 64 << 10); + if (!data_mapped) { + // First call maps data+bss. + data_mapped = true; + MmapFixedNoReserve(meta_begin, meta_end - meta_begin); + } else { + // Mapping continous heap. + // Windows wants 64K alignment. + meta_begin = RoundDownTo(meta_begin, 64 << 10); + meta_end = RoundUpTo(meta_end, 64 << 10); + if (meta_end <= mapped_meta_end) + return; + if (meta_begin < mapped_meta_end) + meta_begin = mapped_meta_end; + MmapFixedNoReserve(meta_begin, meta_end - meta_begin); + mapped_meta_end = meta_end; + } + VPrintf(2, "mapped meta shadow for (%p-%p) at (%p-%p)\n", + addr, addr+size, meta_begin, meta_end); +} + +void MapThreadTrace(uptr addr, uptr size) { + DPrintf("#0: Mapping trace at %p-%p(0x%zx)\n", addr, addr + size, size); + CHECK_GE(addr, kTraceMemBeg); + CHECK_LE(addr + size, kTraceMemEnd); + CHECK_EQ(addr, addr & ~((64 << 10) - 1)); // windows wants 64K alignment + uptr addr1 = (uptr)MmapFixedNoReserve(addr, size); + if (addr1 != addr) { + Printf("FATAL: ThreadSanitizer can not mmap thread trace (%p/%p->%p)\n", + addr, size, addr1); + Die(); + } +} + +static void CheckShadowMapping() { + for (uptr i = 0; i < ARRAY_SIZE(UserRegions); i += 2) { + const uptr beg = UserRegions[i]; + const uptr end = UserRegions[i + 1]; + VPrintf(3, "checking shadow region %p-%p\n", beg, end); + for (uptr p0 = beg; p0 <= end; p0 += (end - beg) / 4) { + for (int x = -1; x <= 1; x++) { + const uptr p = p0 + x; + if (p < beg || p >= end) + continue; + const uptr s = MemToShadow(p); + VPrintf(3, " checking pointer %p -> %p\n", p, s); + CHECK(IsAppMem(p)); + CHECK(IsShadowMem(s)); + CHECK_EQ(p & ~(kShadowCell - 1), ShadowToMem(s)); + const uptr m = (uptr)MemToMeta(p); + CHECK(IsMetaMem(m)); + } + } + } +} + +void Initialize(ThreadState *thr) { + // Thread safe because done before all threads exist. + static bool is_initialized = false; + if (is_initialized) + return; + is_initialized = true; + // We are not ready to handle interceptors yet. + ScopedIgnoreInterceptors ignore; + SanitizerToolName = "ThreadSanitizer"; + // Install tool-specific callbacks in sanitizer_common. + SetCheckFailedCallback(TsanCheckFailed); + + ctx = new(ctx_placeholder) Context; + const char *options = GetEnv(kTsanOptionsEnv); + InitializeFlags(&ctx->flags, options); +#ifndef SANITIZER_GO + InitializeAllocator(); +#endif + InitializeInterceptors(); + CheckShadowMapping(); + InitializePlatform(); + InitializeMutex(); + InitializeDynamicAnnotations(); +#ifndef SANITIZER_GO + InitializeShadowMemory(); +#endif + // Setup correct file descriptor for error reports. + __sanitizer_set_report_path(common_flags()->log_path); + InitializeSuppressions(); +#ifndef SANITIZER_GO + InitializeLibIgnore(); + Symbolizer::GetOrInit()->AddHooks(EnterSymbolizer, ExitSymbolizer); +#endif + StartBackgroundThread(); +#ifndef SANITIZER_GO + SetSandboxingCallback(StopBackgroundThread); +#endif + if (common_flags()->detect_deadlocks) + ctx->dd = DDetector::Create(flags()); + + VPrintf(1, "***** Running under ThreadSanitizer v2 (pid %d) *****\n", + (int)internal_getpid()); + + // Initialize thread 0. + int tid = ThreadCreate(thr, 0, 0, true); + CHECK_EQ(tid, 0); + ThreadStart(thr, tid, internal_getpid()); + ctx->initialized = true; + + if (flags()->stop_on_start) { + Printf("ThreadSanitizer is suspended at startup (pid %d)." + " Call __tsan_resume().\n", + (int)internal_getpid()); + while (__tsan_resumed == 0) {} + } + + OnInitialize(); +} + +int Finalize(ThreadState *thr) { + bool failed = false; + + if (flags()->atexit_sleep_ms > 0 && ThreadCount(thr) > 1) + SleepForMillis(flags()->atexit_sleep_ms); + + // Wait for pending reports. + ctx->report_mtx.Lock(); + CommonSanitizerReportMutex.Lock(); + CommonSanitizerReportMutex.Unlock(); + ctx->report_mtx.Unlock(); + +#ifndef SANITIZER_GO + if (common_flags()->verbosity) + AllocatorPrintStats(); +#endif + + ThreadFinalize(thr); + + if (ctx->nreported) { + failed = true; +#ifndef SANITIZER_GO + Printf("ThreadSanitizer: reported %d warnings\n", ctx->nreported); +#else + Printf("Found %d data race(s)\n", ctx->nreported); +#endif + } + + if (ctx->nmissed_expected) { + failed = true; + Printf("ThreadSanitizer: missed %d expected races\n", + ctx->nmissed_expected); + } + + if (common_flags()->print_suppressions) + PrintMatchedSuppressions(); +#ifndef SANITIZER_GO + if (flags()->print_benign) + PrintMatchedBenignRaces(); +#endif + + failed = OnFinalize(failed); + + StatAggregate(ctx->stat, thr->stat); + StatOutput(ctx->stat); + return failed ? flags()->exitcode : 0; +} + +#ifndef SANITIZER_GO +void ForkBefore(ThreadState *thr, uptr pc) { + ctx->thread_registry->Lock(); + ctx->report_mtx.Lock(); +} + +void ForkParentAfter(ThreadState *thr, uptr pc) { + ctx->report_mtx.Unlock(); + ctx->thread_registry->Unlock(); +} + +void ForkChildAfter(ThreadState *thr, uptr pc) { + ctx->report_mtx.Unlock(); + ctx->thread_registry->Unlock(); + + uptr nthread = 0; + ctx->thread_registry->GetNumberOfThreads(0, 0, &nthread /* alive threads */); + VPrintf(1, "ThreadSanitizer: forked new process with pid %d," + " parent had %d threads\n", (int)internal_getpid(), (int)nthread); + if (nthread == 1) { + internal_start_thread(&BackgroundThread, 0); + } else { + // We've just forked a multi-threaded process. We cannot reasonably function + // after that (some mutexes may be locked before fork). So just enable + // ignores for everything in the hope that we will exec soon. + ctx->after_multithreaded_fork = true; + thr->ignore_interceptors++; + ThreadIgnoreBegin(thr, pc); + ThreadIgnoreSyncBegin(thr, pc); + } +} +#endif + +#ifdef SANITIZER_GO +NOINLINE +void GrowShadowStack(ThreadState *thr) { + const int sz = thr->shadow_stack_end - thr->shadow_stack; + const int newsz = 2 * sz; + uptr *newstack = (uptr*)internal_alloc(MBlockShadowStack, + newsz * sizeof(uptr)); + internal_memcpy(newstack, thr->shadow_stack, sz * sizeof(uptr)); + internal_free(thr->shadow_stack); + thr->shadow_stack = newstack; + thr->shadow_stack_pos = newstack + sz; + thr->shadow_stack_end = newstack + newsz; +} +#endif + +u32 CurrentStackId(ThreadState *thr, uptr pc) { + if (thr->shadow_stack_pos == 0) // May happen during bootstrap. + return 0; + if (pc != 0) { +#ifndef SANITIZER_GO + DCHECK_LT(thr->shadow_stack_pos, thr->shadow_stack_end); +#else + if (thr->shadow_stack_pos == thr->shadow_stack_end) + GrowShadowStack(thr); +#endif + thr->shadow_stack_pos[0] = pc; + thr->shadow_stack_pos++; + } + u32 id = StackDepotPut( + StackTrace(thr->shadow_stack, thr->shadow_stack_pos - thr->shadow_stack)); + if (pc != 0) + thr->shadow_stack_pos--; + return id; +} + +void TraceSwitch(ThreadState *thr) { + thr->nomalloc++; + Trace *thr_trace = ThreadTrace(thr->tid); + Lock l(&thr_trace->mtx); + unsigned trace = (thr->fast_state.epoch() / kTracePartSize) % TraceParts(); + TraceHeader *hdr = &thr_trace->headers[trace]; + hdr->epoch0 = thr->fast_state.epoch(); + ObtainCurrentStack(thr, 0, &hdr->stack0); + hdr->mset0 = thr->mset; + thr->nomalloc--; +} + +Trace *ThreadTrace(int tid) { + return (Trace*)GetThreadTraceHeader(tid); +} + +uptr TraceTopPC(ThreadState *thr) { + Event *events = (Event*)GetThreadTrace(thr->tid); + uptr pc = events[thr->fast_state.GetTracePos()]; + return pc; +} + +uptr TraceSize() { + return (uptr)(1ull << (kTracePartSizeBits + flags()->history_size + 1)); +} + +uptr TraceParts() { + return TraceSize() / kTracePartSize; +} + +#ifndef SANITIZER_GO +extern "C" void __tsan_trace_switch() { + TraceSwitch(cur_thread()); +} + +extern "C" void __tsan_report_race() { + ReportRace(cur_thread()); +} +#endif + +ALWAYS_INLINE +Shadow LoadShadow(u64 *p) { + u64 raw = atomic_load((atomic_uint64_t*)p, memory_order_relaxed); + return Shadow(raw); +} + +ALWAYS_INLINE +void StoreShadow(u64 *sp, u64 s) { + atomic_store((atomic_uint64_t*)sp, s, memory_order_relaxed); +} + +ALWAYS_INLINE +void StoreIfNotYetStored(u64 *sp, u64 *s) { + StoreShadow(sp, *s); + *s = 0; +} + +ALWAYS_INLINE +void HandleRace(ThreadState *thr, u64 *shadow_mem, + Shadow cur, Shadow old) { + thr->racy_state[0] = cur.raw(); + thr->racy_state[1] = old.raw(); + thr->racy_shadow_addr = shadow_mem; +#ifndef SANITIZER_GO + HACKY_CALL(__tsan_report_race); +#else + ReportRace(thr); +#endif +} + +static inline bool HappensBefore(Shadow old, ThreadState *thr) { + return thr->clock.get(old.TidWithIgnore()) >= old.epoch(); +} + +ALWAYS_INLINE +void MemoryAccessImpl1(ThreadState *thr, uptr addr, + int kAccessSizeLog, bool kAccessIsWrite, bool kIsAtomic, + u64 *shadow_mem, Shadow cur) { + StatInc(thr, StatMop); + StatInc(thr, kAccessIsWrite ? StatMopWrite : StatMopRead); + StatInc(thr, (StatType)(StatMop1 + kAccessSizeLog)); + + // This potentially can live in an MMX/SSE scratch register. + // The required intrinsics are: + // __m128i _mm_move_epi64(__m128i*); + // _mm_storel_epi64(u64*, __m128i); + u64 store_word = cur.raw(); + + // scan all the shadow values and dispatch to 4 categories: + // same, replace, candidate and race (see comments below). + // we consider only 3 cases regarding access sizes: + // equal, intersect and not intersect. initially I considered + // larger and smaller as well, it allowed to replace some + // 'candidates' with 'same' or 'replace', but I think + // it's just not worth it (performance- and complexity-wise). + + Shadow old(0); + if (kShadowCnt == 1) { + int idx = 0; +#include "tsan_update_shadow_word_inl.h" + } else if (kShadowCnt == 2) { + int idx = 0; +#include "tsan_update_shadow_word_inl.h" + idx = 1; +#include "tsan_update_shadow_word_inl.h" + } else if (kShadowCnt == 4) { + int idx = 0; +#include "tsan_update_shadow_word_inl.h" + idx = 1; +#include "tsan_update_shadow_word_inl.h" + idx = 2; +#include "tsan_update_shadow_word_inl.h" + idx = 3; +#include "tsan_update_shadow_word_inl.h" + } else if (kShadowCnt == 8) { + int idx = 0; +#include "tsan_update_shadow_word_inl.h" + idx = 1; +#include "tsan_update_shadow_word_inl.h" + idx = 2; +#include "tsan_update_shadow_word_inl.h" + idx = 3; +#include "tsan_update_shadow_word_inl.h" + idx = 4; +#include "tsan_update_shadow_word_inl.h" + idx = 5; +#include "tsan_update_shadow_word_inl.h" + idx = 6; +#include "tsan_update_shadow_word_inl.h" + idx = 7; +#include "tsan_update_shadow_word_inl.h" + } else { + CHECK(false); + } + + // we did not find any races and had already stored + // the current access info, so we are done + if (LIKELY(store_word == 0)) + return; + // choose a random candidate slot and replace it + StoreShadow(shadow_mem + (cur.epoch() % kShadowCnt), store_word); + StatInc(thr, StatShadowReplace); + return; + RACE: + HandleRace(thr, shadow_mem, cur, old); + return; +} + +void UnalignedMemoryAccess(ThreadState *thr, uptr pc, uptr addr, + int size, bool kAccessIsWrite, bool kIsAtomic) { + while (size) { + int size1 = 1; + int kAccessSizeLog = kSizeLog1; + if (size >= 8 && (addr & ~7) == ((addr + 7) & ~7)) { + size1 = 8; + kAccessSizeLog = kSizeLog8; + } else if (size >= 4 && (addr & ~7) == ((addr + 3) & ~7)) { + size1 = 4; + kAccessSizeLog = kSizeLog4; + } else if (size >= 2 && (addr & ~7) == ((addr + 1) & ~7)) { + size1 = 2; + kAccessSizeLog = kSizeLog2; + } + MemoryAccess(thr, pc, addr, kAccessSizeLog, kAccessIsWrite, kIsAtomic); + addr += size1; + size -= size1; + } +} + +ALWAYS_INLINE +bool ContainsSameAccessSlow(u64 *s, u64 a, u64 sync_epoch, bool is_write) { + Shadow cur(a); + for (uptr i = 0; i < kShadowCnt; i++) { + Shadow old(LoadShadow(&s[i])); + if (Shadow::Addr0AndSizeAreEqual(cur, old) && + old.TidWithIgnore() == cur.TidWithIgnore() && + old.epoch() > sync_epoch && + old.IsAtomic() == cur.IsAtomic() && + old.IsRead() <= cur.IsRead()) + return true; + } + return false; +} + +#if defined(__SSE3__) && TSAN_SHADOW_COUNT == 4 +#define SHUF(v0, v1, i0, i1, i2, i3) _mm_castps_si128(_mm_shuffle_ps( \ + _mm_castsi128_ps(v0), _mm_castsi128_ps(v1), \ + (i0)*1 + (i1)*4 + (i2)*16 + (i3)*64)) +ALWAYS_INLINE +bool ContainsSameAccessFast(u64 *s, u64 a, u64 sync_epoch, bool is_write) { + // This is an optimized version of ContainsSameAccessSlow. + // load current access into access[0:63] + const m128 access = _mm_cvtsi64_si128(a); + // duplicate high part of access in addr0: + // addr0[0:31] = access[32:63] + // addr0[32:63] = access[32:63] + // addr0[64:95] = access[32:63] + // addr0[96:127] = access[32:63] + const m128 addr0 = SHUF(access, access, 1, 1, 1, 1); + // load 4 shadow slots + const m128 shadow0 = _mm_load_si128((__m128i*)s); + const m128 shadow1 = _mm_load_si128((__m128i*)s + 1); + // load high parts of 4 shadow slots into addr_vect: + // addr_vect[0:31] = shadow0[32:63] + // addr_vect[32:63] = shadow0[96:127] + // addr_vect[64:95] = shadow1[32:63] + // addr_vect[96:127] = shadow1[96:127] + m128 addr_vect = SHUF(shadow0, shadow1, 1, 3, 1, 3); + if (!is_write) { + // set IsRead bit in addr_vect + const m128 rw_mask1 = _mm_cvtsi64_si128(1<<15); + const m128 rw_mask = SHUF(rw_mask1, rw_mask1, 0, 0, 0, 0); + addr_vect = _mm_or_si128(addr_vect, rw_mask); + } + // addr0 == addr_vect? + const m128 addr_res = _mm_cmpeq_epi32(addr0, addr_vect); + // epoch1[0:63] = sync_epoch + const m128 epoch1 = _mm_cvtsi64_si128(sync_epoch); + // epoch[0:31] = sync_epoch[0:31] + // epoch[32:63] = sync_epoch[0:31] + // epoch[64:95] = sync_epoch[0:31] + // epoch[96:127] = sync_epoch[0:31] + const m128 epoch = SHUF(epoch1, epoch1, 0, 0, 0, 0); + // load low parts of shadow cell epochs into epoch_vect: + // epoch_vect[0:31] = shadow0[0:31] + // epoch_vect[32:63] = shadow0[64:95] + // epoch_vect[64:95] = shadow1[0:31] + // epoch_vect[96:127] = shadow1[64:95] + const m128 epoch_vect = SHUF(shadow0, shadow1, 0, 2, 0, 2); + // epoch_vect >= sync_epoch? + const m128 epoch_res = _mm_cmpgt_epi32(epoch_vect, epoch); + // addr_res & epoch_res + const m128 res = _mm_and_si128(addr_res, epoch_res); + // mask[0] = res[7] + // mask[1] = res[15] + // ... + // mask[15] = res[127] + const int mask = _mm_movemask_epi8(res); + return mask != 0; +} +#endif + +ALWAYS_INLINE +bool ContainsSameAccess(u64 *s, u64 a, u64 sync_epoch, bool is_write) { +#if defined(__SSE3__) && TSAN_SHADOW_COUNT == 4 + bool res = ContainsSameAccessFast(s, a, sync_epoch, is_write); + // NOTE: this check can fail if the shadow is concurrently mutated + // by other threads. + DCHECK_EQ(res, ContainsSameAccessSlow(s, a, sync_epoch, is_write)); + return res; +#else + return ContainsSameAccessSlow(s, a, sync_epoch, is_write); +#endif +} + +ALWAYS_INLINE USED +void MemoryAccess(ThreadState *thr, uptr pc, uptr addr, + int kAccessSizeLog, bool kAccessIsWrite, bool kIsAtomic) { + u64 *shadow_mem = (u64*)MemToShadow(addr); + DPrintf2("#%d: MemoryAccess: @%p %p size=%d" + " is_write=%d shadow_mem=%p {%zx, %zx, %zx, %zx}\n", + (int)thr->fast_state.tid(), (void*)pc, (void*)addr, + (int)(1 << kAccessSizeLog), kAccessIsWrite, shadow_mem, + (uptr)shadow_mem[0], (uptr)shadow_mem[1], + (uptr)shadow_mem[2], (uptr)shadow_mem[3]); +#if TSAN_DEBUG + if (!IsAppMem(addr)) { + Printf("Access to non app mem %zx\n", addr); + DCHECK(IsAppMem(addr)); + } + if (!IsShadowMem((uptr)shadow_mem)) { + Printf("Bad shadow addr %p (%zx)\n", shadow_mem, addr); + DCHECK(IsShadowMem((uptr)shadow_mem)); + } +#endif + + if (kCppMode && *shadow_mem == kShadowRodata) { + // Access to .rodata section, no races here. + // Measurements show that it can be 10-20% of all memory accesses. + StatInc(thr, StatMop); + StatInc(thr, kAccessIsWrite ? StatMopWrite : StatMopRead); + StatInc(thr, (StatType)(StatMop1 + kAccessSizeLog)); + StatInc(thr, StatMopRodata); + return; + } + + FastState fast_state = thr->fast_state; + if (fast_state.GetIgnoreBit()) { + StatInc(thr, StatMop); + StatInc(thr, kAccessIsWrite ? StatMopWrite : StatMopRead); + StatInc(thr, (StatType)(StatMop1 + kAccessSizeLog)); + StatInc(thr, StatMopIgnored); + return; + } + + Shadow cur(fast_state); + cur.SetAddr0AndSizeLog(addr & 7, kAccessSizeLog); + cur.SetWrite(kAccessIsWrite); + cur.SetAtomic(kIsAtomic); + + if (LIKELY(ContainsSameAccess(shadow_mem, cur.raw(), + thr->fast_synch_epoch, kAccessIsWrite))) { + StatInc(thr, StatMop); + StatInc(thr, kAccessIsWrite ? StatMopWrite : StatMopRead); + StatInc(thr, (StatType)(StatMop1 + kAccessSizeLog)); + StatInc(thr, StatMopSame); + return; + } + + if (kCollectHistory) { + fast_state.IncrementEpoch(); + thr->fast_state = fast_state; + TraceAddEvent(thr, fast_state, EventTypeMop, pc); + cur.IncrementEpoch(); + } + + MemoryAccessImpl1(thr, addr, kAccessSizeLog, kAccessIsWrite, kIsAtomic, + shadow_mem, cur); +} + +// Called by MemoryAccessRange in tsan_rtl_thread.cc +ALWAYS_INLINE USED +void MemoryAccessImpl(ThreadState *thr, uptr addr, + int kAccessSizeLog, bool kAccessIsWrite, bool kIsAtomic, + u64 *shadow_mem, Shadow cur) { + if (LIKELY(ContainsSameAccess(shadow_mem, cur.raw(), + thr->fast_synch_epoch, kAccessIsWrite))) { + StatInc(thr, StatMop); + StatInc(thr, kAccessIsWrite ? StatMopWrite : StatMopRead); + StatInc(thr, (StatType)(StatMop1 + kAccessSizeLog)); + StatInc(thr, StatMopSame); + return; + } + + MemoryAccessImpl1(thr, addr, kAccessSizeLog, kAccessIsWrite, kIsAtomic, + shadow_mem, cur); +} + +static void MemoryRangeSet(ThreadState *thr, uptr pc, uptr addr, uptr size, + u64 val) { + (void)thr; + (void)pc; + if (size == 0) + return; + // FIXME: fix me. + uptr offset = addr % kShadowCell; + if (offset) { + offset = kShadowCell - offset; + if (size <= offset) + return; + addr += offset; + size -= offset; + } + DCHECK_EQ(addr % 8, 0); + // If a user passes some insane arguments (memset(0)), + // let it just crash as usual. + if (!IsAppMem(addr) || !IsAppMem(addr + size - 1)) + return; + // Don't want to touch lots of shadow memory. + // If a program maps 10MB stack, there is no need reset the whole range. + size = (size + (kShadowCell - 1)) & ~(kShadowCell - 1); + // UnmapOrDie/MmapFixedNoReserve does not work on Windows, + // so we do it only for C/C++. + if (kGoMode || size < common_flags()->clear_shadow_mmap_threshold) { + u64 *p = (u64*)MemToShadow(addr); + CHECK(IsShadowMem((uptr)p)); + CHECK(IsShadowMem((uptr)(p + size * kShadowCnt / kShadowCell - 1))); + // FIXME: may overwrite a part outside the region + for (uptr i = 0; i < size / kShadowCell * kShadowCnt;) { + p[i++] = val; + for (uptr j = 1; j < kShadowCnt; j++) + p[i++] = 0; + } + } else { + // The region is big, reset only beginning and end. + const uptr kPageSize = 4096; + u64 *begin = (u64*)MemToShadow(addr); + u64 *end = begin + size / kShadowCell * kShadowCnt; + u64 *p = begin; + // Set at least first kPageSize/2 to page boundary. + while ((p < begin + kPageSize / kShadowSize / 2) || ((uptr)p % kPageSize)) { + *p++ = val; + for (uptr j = 1; j < kShadowCnt; j++) + *p++ = 0; + } + // Reset middle part. + u64 *p1 = p; + p = RoundDown(end, kPageSize); + UnmapOrDie((void*)p1, (uptr)p - (uptr)p1); + MmapFixedNoReserve((uptr)p1, (uptr)p - (uptr)p1); + // Set the ending. + while (p < end) { + *p++ = val; + for (uptr j = 1; j < kShadowCnt; j++) + *p++ = 0; + } + } +} + +void MemoryResetRange(ThreadState *thr, uptr pc, uptr addr, uptr size) { + MemoryRangeSet(thr, pc, addr, size, 0); +} + +void MemoryRangeFreed(ThreadState *thr, uptr pc, uptr addr, uptr size) { + // Processing more than 1k (4k of shadow) is expensive, + // can cause excessive memory consumption (user does not necessary touch + // the whole range) and most likely unnecessary. + if (size > 1024) + size = 1024; + CHECK_EQ(thr->is_freeing, false); + thr->is_freeing = true; + MemoryAccessRange(thr, pc, addr, size, true); + thr->is_freeing = false; + if (kCollectHistory) { + thr->fast_state.IncrementEpoch(); + TraceAddEvent(thr, thr->fast_state, EventTypeMop, pc); + } + Shadow s(thr->fast_state); + s.ClearIgnoreBit(); + s.MarkAsFreed(); + s.SetWrite(true); + s.SetAddr0AndSizeLog(0, 3); + MemoryRangeSet(thr, pc, addr, size, s.raw()); +} + +void MemoryRangeImitateWrite(ThreadState *thr, uptr pc, uptr addr, uptr size) { + if (kCollectHistory) { + thr->fast_state.IncrementEpoch(); + TraceAddEvent(thr, thr->fast_state, EventTypeMop, pc); + } + Shadow s(thr->fast_state); + s.ClearIgnoreBit(); + s.SetWrite(true); + s.SetAddr0AndSizeLog(0, 3); + MemoryRangeSet(thr, pc, addr, size, s.raw()); +} + +ALWAYS_INLINE USED +void FuncEntry(ThreadState *thr, uptr pc) { + StatInc(thr, StatFuncEnter); + DPrintf2("#%d: FuncEntry %p\n", (int)thr->fast_state.tid(), (void*)pc); + if (kCollectHistory) { + thr->fast_state.IncrementEpoch(); + TraceAddEvent(thr, thr->fast_state, EventTypeFuncEnter, pc); + } + + // Shadow stack maintenance can be replaced with + // stack unwinding during trace switch (which presumably must be faster). + DCHECK_GE(thr->shadow_stack_pos, thr->shadow_stack); +#ifndef SANITIZER_GO + DCHECK_LT(thr->shadow_stack_pos, thr->shadow_stack_end); +#else + if (thr->shadow_stack_pos == thr->shadow_stack_end) + GrowShadowStack(thr); +#endif + thr->shadow_stack_pos[0] = pc; + thr->shadow_stack_pos++; +} + +ALWAYS_INLINE USED +void FuncExit(ThreadState *thr) { + StatInc(thr, StatFuncExit); + DPrintf2("#%d: FuncExit\n", (int)thr->fast_state.tid()); + if (kCollectHistory) { + thr->fast_state.IncrementEpoch(); + TraceAddEvent(thr, thr->fast_state, EventTypeFuncExit, 0); + } + + DCHECK_GT(thr->shadow_stack_pos, thr->shadow_stack); +#ifndef SANITIZER_GO + DCHECK_LT(thr->shadow_stack_pos, thr->shadow_stack_end); +#endif + thr->shadow_stack_pos--; +} + +void ThreadIgnoreBegin(ThreadState *thr, uptr pc) { + DPrintf("#%d: ThreadIgnoreBegin\n", thr->tid); + thr->ignore_reads_and_writes++; + CHECK_GT(thr->ignore_reads_and_writes, 0); + thr->fast_state.SetIgnoreBit(); +#ifndef SANITIZER_GO + if (!ctx->after_multithreaded_fork) + thr->mop_ignore_set.Add(CurrentStackId(thr, pc)); +#endif +} + +void ThreadIgnoreEnd(ThreadState *thr, uptr pc) { + DPrintf("#%d: ThreadIgnoreEnd\n", thr->tid); + thr->ignore_reads_and_writes--; + CHECK_GE(thr->ignore_reads_and_writes, 0); + if (thr->ignore_reads_and_writes == 0) { + thr->fast_state.ClearIgnoreBit(); +#ifndef SANITIZER_GO + thr->mop_ignore_set.Reset(); +#endif + } +} + +void ThreadIgnoreSyncBegin(ThreadState *thr, uptr pc) { + DPrintf("#%d: ThreadIgnoreSyncBegin\n", thr->tid); + thr->ignore_sync++; + CHECK_GT(thr->ignore_sync, 0); +#ifndef SANITIZER_GO + if (!ctx->after_multithreaded_fork) + thr->sync_ignore_set.Add(CurrentStackId(thr, pc)); +#endif +} + +void ThreadIgnoreSyncEnd(ThreadState *thr, uptr pc) { + DPrintf("#%d: ThreadIgnoreSyncEnd\n", thr->tid); + thr->ignore_sync--; + CHECK_GE(thr->ignore_sync, 0); +#ifndef SANITIZER_GO + if (thr->ignore_sync == 0) + thr->sync_ignore_set.Reset(); +#endif +} + +bool MD5Hash::operator==(const MD5Hash &other) const { + return hash[0] == other.hash[0] && hash[1] == other.hash[1]; +} + +#if TSAN_DEBUG +void build_consistency_debug() {} +#else +void build_consistency_release() {} +#endif + +#if TSAN_COLLECT_STATS +void build_consistency_stats() {} +#else +void build_consistency_nostats() {} +#endif + +#if TSAN_SHADOW_COUNT == 1 +void build_consistency_shadow1() {} +#elif TSAN_SHADOW_COUNT == 2 +void build_consistency_shadow2() {} +#elif TSAN_SHADOW_COUNT == 4 +void build_consistency_shadow4() {} +#else +void build_consistency_shadow8() {} +#endif + +} // namespace __tsan + +#ifndef SANITIZER_GO +// Must be included in this file to make sure everything is inlined. +#include "tsan_interface_inl.h" +#endif |
