build openjdk with fsanitizer=thread

[Jie He]

Oh, I misunderstand the race object, 
but _owner also appears to be protected by the member var _lock within class Mutex.

-----Original Message-----
From: Dmitry Vyukov <dvyukov at google.com> 
Sent: Wednesday, February 26, 2020 9:56 PM
To: Jie He <Jie.He at arm.com>
Cc: Arthur Eubanks <aeubanks at google.com>; tsan-dev at openjdk.java.net; nd <nd at arm.com>; thread-sanitizer <thread-sanitizer at googlegroups.com>
Subject: Re: build openjdk with fsanitizer=thread

On Wed, Feb 26, 2020 at 2:46 PM Jie He <Jie.He at arm.com> wrote:
>
> Is this case you mentioned "_owned_by_self"
>
> >     #0 Mutex::owned_by_self() const /home/wave/workspace/jdk_master/src/hotspot/share/runtime/mutex.cpp:301:10 (libjvm.so+0x1925966)
> >     #1 assert_lock_strong(Mutex const*) /home/wave/workspace/jdk_master/src/hotspot/share/runtime/mutexLocker.cpp:187:13 (libjvm.so+0x19272fa)
> >     #2 MutexLocker::~MutexLocker() /home/wave/workspace/jdk_master/src/hotspot/share/runtime/mutexLocker.hpp:237:7 (libjvm.so+0x33da8a)
> >     #3 G1YoungRemSetSamplingThread::stop_service() /home/wave/workspace/jdk_master/src/hotspot/share/gc/g1/g1YoungRemSetSamplingThread.cpp:129:1 (libjvm.so+0x10c50e0)
> >     #4 ConcurrentGCThread::stop() /home/wave/workspace/jdk_master/src/hotspot/share/gc/shared/concurrentGCThread.cpp:65:3 (libjvm.so+0xc9fa11)
> >     #5 G1CollectedHeap::stop() /home/wave/workspace/jdk_master/src/hotspot/share/gc/g1/g1CollectedHeap.cpp:1867:31 (libjvm.so+0xfae058)
> >     #6 before_exit(JavaThread*) /home/wave/workspace/jdk_master/src/hotspot/share/runtime/java.cpp:461:21 (libjvm.so+0x1215b84)
> >     #7 Threads::destroy_vm() /home/wave/workspace/jdk_master/src/hotspot/share/runtime/thread.cpp:4418:3 (libjvm.so+0x1e326ee)
> >     #8 jni_DestroyJavaVM_inner(JavaVM_*) /home/wave/workspace/jdk_master/src/hotspot/share/prims/jni.cpp:3989:7 (libjvm.so+0x137a5eb)
> >     #9 jni_DestroyJavaVM /home/wave/workspace/jdk_master/src/hotspot/share/prims/jni.cpp:4007:14 (libjvm.so+0x137a3ef)
> >     #10 JavaMain
>
> Seems thread::current() is a TLS variable, refer to the code:
>
> inline Thread* Thread::current_or_null() { #ifndef 
> USE_LIBRARY_BASED_TLS_ONLY
>   return _thr_current;
> #else
>   if (ThreadLocalStorage::is_initialized()) {
>     return ThreadLocalStorage::thread();
>   }
>   return NULL;
> #endif
> }

The race is on Mutex::owner_ based on the fact that another thread does a write, and on allocation stack, and the race just seems to be visible in the code and is a common race.