[foreign+linkToNative] RFR: 8230202: Fix failure of foreign/pthread/Threads.java with linkToNative

[Nick Gasson]

Hi,

Bug: https://bugs.openjdk.java.net/browse/JDK-8230202
Webrev: http://cr.openjdk.java.net/~ngasson/foreign/8230202/webrev.0/

This patch applies the fix for 8226250 (callback from native threads) to
linkToNative.

In the upcall stub `__ get_thread(...)' calls Thread::current() but that
assumes the calling thread is already attached to the VM. Moved the
existing logic to handle attaching to the VM as a daemon in this case
out of the four upcall implementations into a static method in
UniversalUpcallHandler. We can then call this from the linkToNative
upcall stub.

Also fixed a potential race in Threads.java between the native thread
starting and the VM exiting after main() returns.

The new calls to in_bytes() are unrelated: just fixing the debug build.

--

I'm wondering what the status of linkToNative is at that the moment? Is 
there a list of missing features/bugs that need to be fixed before it 
can replace the JNI-based fastpath?

Thanks,
Nick