RFR (XS) 8213992: Rename and make DieOnSafepointTimeout the diagnostic option

[Aleksey Shipilev]

On 11/19/18 6:08 AM, David Holmes wrote:
>> David suggested making the option "product", but I don't like it very much: "product" option
>> suggests this is a production-grade feature and it comes with expectations of support, which is
>> interesting in itself when product feature crashes the VM. "diagnostic" keeps this mode available in
>> product builds without the attached notion of support. Users that want fail-fast VM crash can then
>> use that option on "we know what we are doing" basis.
> 
> I feel a little uncomfortable that "diagnostic" is being used as a synonym for "unsupported
> product". If you really want to fail-fast in production then you're looking for a production flag
> not a "diagnostic" one IMHO. I won't fight it but I'd like to know what others think.

Yup, let's hear it. I don't want to bikeshed this too much :)

To re-iterate: I don't really want to introduce the hard-to-retract product option. Rather, I would
like to expose the flag that we are using for debugging into release builds, so it could both used
by us for our release-mode debugging, and by power users who know what they are doing. It seems
"diagnostic" hits the spot here. Also, symmetry against other Abort* flags...

>> Fix:
>>
>> diff -r 9ad663e63da5 -r 132db6e99f77 src/hotspot/share/runtime/globals.hpp
>> --- a/src/hotspot/share/runtime/globals.hpp    Fri Nov 16 12:02:08 2018 +0100
>> +++ b/src/hotspot/share/runtime/globals.hpp    Fri Nov 16 13:35:16 2018 +0100
>> @@ -498,7 +498,7 @@
>>             "Time out and warn or fail after SafepointTimeoutDelay "          \
>>             "milliseconds if failed to reach safepoint")                      \
>>                                                                               \
>> -  develop(bool, DieOnSafepointTimeout, false,                               \
>> +  diagnostic(bool, AbortVMOnSafepointTimeout, false,                        \
>>             "Die upon failure to reach safepoint (see SafepointTimeout)")     \
> s/Die/Abort
> 
> Thanks.

Done in my local patch queue, thanks!

-Aleksey