RFR(xs): 8150619: Improve thread based logging introduced with 8149036

[Coleen Phillimore]

Hi I think David should sponsor this once he's happy all the nits are out.
Thank you for adding the test.  Does this output come out for every 
platform?  Sometimes there's a race with threads exiting and not getting 
the 'exiting' log messages.  We've had trouble with reliability of the 
tests we've added and have had to dial back the messages we look for.  
Do you have windows systems to run this on?
Thanks,
Coleen

On 2/25/16 8:19 AM, Thomas Stüfe wrote:
> Hi all,
>
> please review and sponsor this tiny addition to 8149036. These are some
> tiny cleanups which could not be added to the original change anymore
> because it was already pushed.
>
> bug: https://bugs.openjdk.java.net/browse/JDK-8150619
> webrev:
> http://cr.openjdk.java.net/~stuefe/webrevs/8150619-addon-to-thread-logging/webrev.00/webrev/index.html
>
> Original mail thread for 8149036:
> http://mail.openjdk.java.net/pipermail/hotspot-runtime-dev/2016-February/018099.html
>
> The change unifies the logging messages for all platforms and all log sites
> as much as possible.
>
> Please note: "tid" always refers to whatever os::current_thread_id()
> returns. This may be a pthread_t (AIX, BSD), a kernel thread id or similar
> (Mac, Linux, Solaris), or a windows thread id. Beside printing the "tid", I
> print out additional thread ids where it may be interesting, especially at
> thread start and attach. On AIX, I print the kernel thread id, on
> Linux/Mac, the pthread id.
>
> There are some instances where I have only one and not the other:
> - after a call to pthread_create(), I only have the pthread id of the
> newborn thread, not the kernel thread id, so this is all I can print.
> - in shared code, all I have or all I can print without making the code to
> complicated is the "tid"
>
> Finally, the change adds a jtreg test to logging, to test the new logging
> switches.
>
> Thanks & Kind Regards, Thomas