diff options
| -rw-r--r-- | include/sanitizer/common_interface_defs.h | 2 | ||||
| -rw-r--r-- | lib/asan/asan_rtl.cc | 4 | ||||
| -rw-r--r-- | lib/sanitizer_common/sanitizer_coverage.cc | 43 | ||||
| -rw-r--r-- | lib/sanitizer_common/sanitizer_internal_defs.h | 1 |
4 files changed, 32 insertions, 18 deletions
diff --git a/include/sanitizer/common_interface_defs.h b/include/sanitizer/common_interface_defs.h index 368791473..798f0c52f 100644 --- a/include/sanitizer/common_interface_defs.h +++ b/include/sanitizer/common_interface_defs.h @@ -47,6 +47,8 @@ extern "C" { void __sanitizer_unaligned_store32(void *p, uint32_t x); void __sanitizer_unaligned_store64(void *p, uint64_t x); + // Initialize coverage. + void __sanitizer_cov_init(); // Record and dump coverage info. void __sanitizer_cov_dump(); diff --git a/lib/asan/asan_rtl.cc b/lib/asan/asan_rtl.cc index be3b90500..f10047a0d 100644 --- a/lib/asan/asan_rtl.cc +++ b/lib/asan/asan_rtl.cc @@ -664,8 +664,10 @@ static void AsanInitInternal() { if (flags()->atexit) Atexit(asan_atexit); - if (flags()->coverage) + if (flags()->coverage) { + __sanitizer_cov_init(); Atexit(__sanitizer_cov_dump); + } // interceptors InitTlsSize(); diff --git a/lib/sanitizer_common/sanitizer_coverage.cc b/lib/sanitizer_common/sanitizer_coverage.cc index c305bed34..f516cea64 100644 --- a/lib/sanitizer_common/sanitizer_coverage.cc +++ b/lib/sanitizer_common/sanitizer_coverage.cc @@ -40,23 +40,31 @@ #include "sanitizer_stacktrace.h" #include "sanitizer_flags.h" -struct CovData { - BlockingMutex mu; - InternalMmapVector<uptr> v; - atomic_uint32_t guard; -}; +atomic_uint32_t dump_once_guard; // Ensure that CovDump runs only once. -static uptr cov_data_placeholder[(sizeof(CovData) / sizeof(uptr)) + 1]; -COMPILER_CHECK(sizeof(cov_data_placeholder) >= sizeof(CovData)); -static CovData *cov_data = reinterpret_cast<CovData*>(cov_data_placeholder); +// pc_array is the array containing the covered PCs. +// To make the pc_array thread- and AS- safe it has to be large enough. +// 128M counters "ought to be enough for anybody" (4M on 32-bit). +// pc_array is allocated with MmapNoReserveOrDie and so it uses only as +// much RAM as it really needs. +static const uptr kPcArraySize = FIRST_32_SECOND_64(1 << 22, 1 << 27); +static uptr *pc_array; +static atomic_uintptr_t pc_array_index; namespace __sanitizer { // Simply add the pc into the vector under lock. If the function is called more // than once for a given PC it will be inserted multiple times, which is fine. static void CovAdd(uptr pc) { - BlockingMutexLock lock(&cov_data->mu); - cov_data->v.push_back(pc); + if (!pc_array) return; + uptr idx = atomic_fetch_add(&pc_array_index, 1, memory_order_relaxed); + CHECK_LT(idx, kPcArraySize); + pc_array[idx] = pc; +} + +void CovInit() { + pc_array = reinterpret_cast<uptr *>( + MmapNoReserveOrDie(sizeof(uptr) * kPcArraySize, "CovInit")); } static inline bool CompareLess(const uptr &a, const uptr &b) { @@ -66,13 +74,13 @@ static inline bool CompareLess(const uptr &a, const uptr &b) { // Dump the coverage on disk. void CovDump() { #if !SANITIZER_WINDOWS - if (atomic_fetch_add(&cov_data->guard, 1, memory_order_relaxed) != 0) return; - BlockingMutexLock lock(&cov_data->mu); - InternalMmapVector<uptr> &v = cov_data->v; - InternalSort(&v, v.size(), CompareLess); - InternalMmapVector<u32> offsets(v.size()); - const uptr *vb = v.data(); - const uptr *ve = vb + v.size(); + if (atomic_fetch_add(&dump_once_guard, 1, memory_order_relaxed)) + return; + uptr size = atomic_load(&pc_array_index, memory_order_relaxed); + InternalSort(&pc_array, size, CompareLess); + InternalMmapVector<u32> offsets(size); + const uptr *vb = pc_array; + const uptr *ve = vb + size; MemoryMappingLayout proc_maps(/*cache_enabled*/false); uptr mb, me, off, prot; InternalScopedBuffer<char> module(4096); @@ -116,4 +124,5 @@ SANITIZER_INTERFACE_ATTRIBUTE void __sanitizer_cov() { CovAdd(StackTrace::GetPreviousInstructionPc(GET_CALLER_PC())); } SANITIZER_INTERFACE_ATTRIBUTE void __sanitizer_cov_dump() { CovDump(); } +SANITIZER_INTERFACE_ATTRIBUTE void __sanitizer_cov_init() { CovInit(); } } // extern "C" diff --git a/lib/sanitizer_common/sanitizer_internal_defs.h b/lib/sanitizer_common/sanitizer_internal_defs.h index b0ced9377..6c3cf4e03 100644 --- a/lib/sanitizer_common/sanitizer_internal_defs.h +++ b/lib/sanitizer_common/sanitizer_internal_defs.h @@ -104,6 +104,7 @@ extern "C" { void __sanitizer_report_error_summary(const char *error_summary); SANITIZER_INTERFACE_ATTRIBUTE void __sanitizer_cov_dump(); + SANITIZER_INTERFACE_ATTRIBUTE void __sanitizer_cov_init(); SANITIZER_INTERFACE_ATTRIBUTE void __sanitizer_cov(); SANITIZER_INTERFACE_ATTRIBUTE void __sanitizer_annotate_contiguous_container(const void *beg, |