RFR(L): 8193257: PPC64, s390 implementation for Thread-local handshakes

[Lindenmaier, Goetz]

Hi Martin, 

I had a look at your change.

I see you enabled it per default?

macroAssembler_ppc/s390.cpp: 
MacroAssembler::safepoint_poll()
Could you add some comment that says what this is doing?
As it's not doing a safepoint_poll ... its just preparing it, right?
Maybe also "slow_target" should be "do_safepoint".
  
templateInterpreterGenerator_ppc.cpp:
Why do you change memory ordering from release() to lwsync()?

sharedRuntime_ppc/s390.cpp
If I understand right you skip the safepoint instruction.
Why that? Could you please document that this differs 
from the other platforms here?

Best regards,
  Goetz.

> -----Original Message-----
> From: Doerr, Martin
> Sent: Freitag, 8. Dezember 2017 17:17
> To: hotspot-dev developers (hotspot-dev at openjdk.java.net) <hotspot-
> dev at openjdk.java.net>; Lindenmaier, Goetz
> <goetz.lindenmaier at sap.com>; Schmidt, Lutz <lutz.schmidt at sap.com>
> Subject: RFR(L): 8193257: PPC64, s390 implementation for Thread-local
> handshakes
> 
> Hi,
> 
> 
> 
> I've implemented Thread-local handshakes on PPC64 and s390.
> 
> 
> 
> We may improve it by using SIGTRAP-based polling on these 2 platforms in
> the future (which requires changes in shared code).
> 
> For now, I just implemented it like on the other platforms without further
> improvements.
> 
> 
> 
> Webrev is here:
> 
> http://cr.openjdk.java.net/~mdoerr/8193257_PPC64_s390_Thread-
> local_hs/webrev.00/
> 
> 
> 
> Please review.
> 
> 
> 
> Best regards,
> 
> Martin
> 
>