Index: lib/sanitizer_common/sanitizer_thread_registry.h =================================================================== --- lib/sanitizer_common/sanitizer_thread_registry.h +++ lib/sanitizer_common/sanitizer_thread_registry.h @@ -50,6 +50,8 @@ u32 parent_tid; ThreadContextBase *next; // For storing thread contexts in a list. + atomic_uint32_t thread_destroyed; // To address race of Joined vs Finished + void SetName(const char *new_name); void SetDead(); @@ -60,6 +62,9 @@ u32 _parent_tid, void *arg); void Reset(); + void SetDestroyed(); + bool GetDestroyed(); + // The following methods may be overriden by subclasses. // Some of them take opaque arg that may be optionally be used // by subclasses. Index: lib/sanitizer_common/sanitizer_thread_registry.cc =================================================================== --- lib/sanitizer_common/sanitizer_thread_registry.cc +++ lib/sanitizer_common/sanitizer_thread_registry.cc @@ -21,6 +21,7 @@ status(ThreadStatusInvalid), detached(false), workerthread(false), parent_tid(0), next(0) { name[0] = '\0'; + atomic_store(&thread_destroyed, 0, memory_order_release); } ThreadContextBase::~ThreadContextBase() { @@ -44,6 +45,14 @@ OnDead(); } +void ThreadContextBase::SetDestroyed() { + atomic_store(&thread_destroyed, 1, memory_order_release); +} + +bool ThreadContextBase::GetDestroyed() { + return !!atomic_load(&thread_destroyed, memory_order_acquire); +} + void ThreadContextBase::SetJoined(void *arg) { // FIXME(dvyukov): print message and continue (it's user error). CHECK_EQ(false, detached); @@ -85,6 +94,7 @@ void ThreadContextBase::Reset() { status = ThreadStatusInvalid; SetName(0); + atomic_store(&thread_destroyed, 0, memory_order_release); OnReset(); } @@ -243,16 +253,25 @@ } void ThreadRegistry::JoinThread(u32 tid, void *arg) { - BlockingMutexLock l(&mtx_); - CHECK_LT(tid, n_contexts_); - ThreadContextBase *tctx = threads_[tid]; - CHECK_NE(tctx, 0); - if (tctx->status == ThreadStatusInvalid) { - Report("%s: Join of non-existent thread\n", SanitizerToolName); - return; - } - tctx->SetJoined(arg); - QuarantinePush(tctx); + bool destroyed = false; + do { + { + BlockingMutexLock l(&mtx_); + CHECK_LT(tid, n_contexts_); + ThreadContextBase *tctx = threads_[tid]; + CHECK_NE(tctx, 0); + if (tctx->status == ThreadStatusInvalid) { + Report("%s: Join of non-existent thread\n", SanitizerToolName); + return; + } + if ((destroyed = tctx->GetDestroyed())) { + tctx->SetJoined(arg); + QuarantinePush(tctx); + } + } + if (!destroyed) + internal_sched_yield(); + } while (!destroyed); } // Normally this is called when the thread is about to exit. If @@ -281,6 +300,7 @@ tctx->SetDead(); QuarantinePush(tctx); } + tctx->SetDestroyed(); } void ThreadRegistry::StartThread(u32 tid, tid_t os_id, bool workerthread,