RFR 8189208: Cleanup ancient argument processing code

[gerard ziemski]

Thank you Claes, Harold, David for your reviews!


On 5/1/19 5:27 PM, David Holmes wrote:
> Hi Gerard,
>
> Mostly looks good - a couple of comments below.
>
> On 2/05/2019 1:45 am, gerard ziemski wrote:
>> Hi all,
>>
>> Please review this fix, which:
>>
>> #1 removes overriding of “UseLinuxPosixThreadCPUClocks” to different 
>> default values in older JDKs
>> #2 removes checks for “supports_thread_park_blocker” and all of the 
>> supporting code
>
> src/hotspot/share/include/jvm.h
>
> -     unsigned int reserved2;
> +     unsigned int reserved2 : 2;
>
> This change seems wrong to me. reserved2 is a full size int (I don't 
> know why this struct has been laid out this way but it has). To handle 
> the deleted _thread_park_blocker field you can either:
>
> a) don't delete it but rename it to unused_slot; or
> b) change the following "unsigned int : 29;" to "unsigned int : 30;" 
> to take up the extra bit.

Fixed.


>
> Also note that the entire comment block from line 1284 can be deleted.
>
> As a follow up we should also remove all the post_vm_init_hook_enabled 
> code and pending_list_uses_discovered_field code.

Since I had to put in the above fix, I decided to also remove 
"post_vm_init_hook_enabled" and "pending_list_uses_discovered_field" 
code as you pointed out.


> Or more generally cleanup all the legacy code in JDK_Version that was 
> there to allow different JDKs to run on different versions of hotspot 
> (eg dll_lookup of JDK_GetVersionInfo0).

I will handle that in a followup 
https://bugs.openjdk.java.net/browse/JDK-8223261


>
> Minor nit in threadService.cpp
>
>     // Support for JSR-166 locks
> !   if (_thread_status == java_lang_Thread::PARKED ||
> !          _thread_status == java_lang_Thread::PARKED_TIMED) {
>
> Please fix the indent so _thread_status line up. (The original code 
> wasn't correctly indented.)

Fixed, following the existing style.

New webrev: http://cr.openjdk.java.net/~gziemski/8189208_rev2


Cheers

>> Bug: https://bugs.openjdk.java.net/browse/JDK-8189208
>> Web rev: http://cr.openjdk.java.net/~gziemski/8189208_rev1
>> Tested with Mach5 tier1,2,3, another Mach5 tier1,2,3,4,5 in progress…