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Diffstat (limited to 'lib/scudo/scudo_tsd_exclusive.cpp')
-rw-r--r-- | lib/scudo/scudo_tsd_exclusive.cpp | 68 |
1 files changed, 68 insertions, 0 deletions
diff --git a/lib/scudo/scudo_tsd_exclusive.cpp b/lib/scudo/scudo_tsd_exclusive.cpp new file mode 100644 index 000000000..1084dfac9 --- /dev/null +++ b/lib/scudo/scudo_tsd_exclusive.cpp @@ -0,0 +1,68 @@ +//===-- scudo_tsd_exclusive.cpp ---------------------------------*- C++ -*-===// +// +// The LLVM Compiler Infrastructure +// +// This file is distributed under the University of Illinois Open Source +// License. See LICENSE.TXT for details. +// +//===----------------------------------------------------------------------===// +/// +/// Scudo exclusive TSD implementation. +/// +//===----------------------------------------------------------------------===// + +#include "scudo_tsd.h" + +#if SCUDO_TSD_EXCLUSIVE + +namespace __scudo { + +static pthread_once_t GlobalInitialized = PTHREAD_ONCE_INIT; +static pthread_key_t PThreadKey; + +__attribute__((tls_model("initial-exec"))) +THREADLOCAL ThreadState ScudoThreadState = ThreadNotInitialized; +__attribute__((tls_model("initial-exec"))) +THREADLOCAL ScudoTSD TSD; + +// Fallback TSD for when the thread isn't initialized yet or is torn down. It +// can be shared between multiple threads and as such must be locked. +ScudoTSD FallbackTSD; + +static void teardownThread(void *Ptr) { + uptr I = reinterpret_cast<uptr>(Ptr); + // The glibc POSIX thread-local-storage deallocation routine calls user + // provided destructors in a loop of PTHREAD_DESTRUCTOR_ITERATIONS. + // We want to be called last since other destructors might call free and the + // like, so we wait until PTHREAD_DESTRUCTOR_ITERATIONS before draining the + // quarantine and swallowing the cache. + if (I > 1) { + // If pthread_setspecific fails, we will go ahead with the teardown. + if (LIKELY(pthread_setspecific(PThreadKey, + reinterpret_cast<void *>(I - 1)) == 0)) + return; + } + TSD.commitBack(); + ScudoThreadState = ThreadTornDown; +} + + +static void initOnce() { + CHECK_EQ(pthread_key_create(&PThreadKey, teardownThread), 0); + initScudo(); + FallbackTSD.init(/*Shared=*/true); +} + +void initThread(bool MinimalInit) { + CHECK_EQ(pthread_once(&GlobalInitialized, initOnce), 0); + if (UNLIKELY(MinimalInit)) + return; + CHECK_EQ(pthread_setspecific(PThreadKey, reinterpret_cast<void *>( + GetPthreadDestructorIterations())), 0); + TSD.init(/*Shared=*/false); + ScudoThreadState = ThreadInitialized; +} + +} // namespace __scudo + +#endif // SCUDO_TSD_EXCLUSIVE |