Defer unloader JNI libraries of boot classpath as late as possible.
Also don't try to lock at this point.
A lock would run a checkpoint on threads that are dying, and this can
lead to crashes, eg:
https://build.chromium.org/p/client.art/builders/host-x86-cms/builds/4412/steps/test%20debuggable/logs/stdio
+*** *** *** *** *** *** *** *** *** *** *** *** *** *** *** ***
+Fatal signal 11 (SIGSEGV), code 1 (SEGV_MAPERR) fault addr (nil)
+OS: Linux 4.4.0-78-generic (x86_64)
+Cmdline: <unset>
+Thread: 10797 "Shutdown thread"
+Registers:
+ eax: 0x00000000 ebx: 0xf739c104 ecx: 0xf739f794 edx: 0x00000001
+ edi: 0x00000000 esi: 0x56748c54 ebp: 0xffd2bd18 esp: 0xffd2bcc0
+ eip: 0xf6c18c8c eflags: 0x00010246 [ PF ZF IF ]
+ cs: 0x00000023 ds: 0x0000002b es: 0x0000002b fs: 0x0000006b
+ gs: 0x00000063 ss: 0x0000002b
+Backtrace:
+ #00 pc 001ffc8c /b/build/slave/host-x86-cms/build/out/host/linux-x86/lib/libartd.so (art::Thread::CheckEmptyCheckpointFromMutex()+428)
+ art::Thread::ReadFlag(art::ThreadFlag) const
+ art/runtime/thread.h:1089
+ art::Thread::CheckEmptyCheckpointFromMutex()
+ art/runtime/thread-inl.h:94
+ #01 pc 001fb40e /b/build/slave/host-x86-cms/build/out/host/linux-x86/lib/libartd.so (art::Mutex::ExclusiveLock(art::Thread*)+462)
+ art::Mutex::ExclusiveLock(art::Thread*)
+ art/runtime/base/mutex.cc:382
+ #02 pc 0064d9b7 /b/build/slave/host-x86-cms/build/out/host/linux-x86/lib/libartd.so (art::Libraries::UnloadBootNativeLibraries(_JavaVM*)+103)
+ MutexLock
+ art/runtime/base/mutex.h:431
+ art::Libraries::UnloadBootNativeLibraries(_JavaVM*)
+ art/runtime/jni/java_vm_ext.cc:230
Test: 004-ThreadStress
Change-Id: I7f9b69590983ff4e3276a0ad1ef5c7453d692b04
2 files changed
