RFR(m): 8221734: Deoptimize with handshakes

[Robbin Ehn]

Hi Patricio,

On 2019-05-20 19:14, Patricio Chilano wrote:
> Hi Robbin,
> 
> Changes to biased locking look good! Thanks for the change.

Thanks, great!

> 
> nit:
> --- a/src/hotspot/share/runtime/deoptimization.cpp
> +++ b/src/hotspot/share/runtime/deoptimization.cpp
> @@ -1318,3 +1318,2 @@
>       oop obj = (objects_to_revoke->at(i))();
> -   markOop mark = obj->mark();
> BiasedLocking::revoke_own_locks_in_handshake(objects_to_revoke->at(i), thread);
> 

Thanks, I'll fix this locally. Crossing fingers I do not need a v5 :)

/Robbin

> 
> Thanks!
> 
> Patricio
> 
> On 5/20/19 5:04 AM, Robbin Ehn wrote:
>> Hi all, please see this update v4.
>>
>> I have fixed the simplification Patricio talked about and David's nit.
>>
>> The interesting part is now the full diff of bias locking cpp file:
>> http://cr.openjdk.java.net/~rehn/8221734/v4/webrev/src/hotspot/share/runtime/biasedLocking.cpp.sdiff.html 
>>
>> It's very clean.
>>
>> Full:
>> http://cr.openjdk.java.net/~rehn/8221734/v4/
>> Inc:
>> http://cr.openjdk.java.net/~rehn/8221734/v4/inc/
>>
>> I have seen no issues in T1-7, KS and other assorted testing.
>>
>> Thanks, Robbin
>>
>>
>> On 2019-04-25 14:05, Robbin Ehn wrote:
>>> Hi all, please review.
>>>
>>> Let's deopt with handshakes.
>>> Removed VM op Deoptimize, instead we handshake.
>>> Locks needs to be inflate since we are not in a safepoint.
>>>
>>> Goes on top of:
>>> https://mail.openjdk.java.net/pipermail/hotspot-compiler-dev/2019-April/033491.html 
>>>
>>>
>>> Code:
>>> http://cr.openjdk.java.net/~rehn/8221734/v1/webrev/index.html
>>> Issue:
>>> https://bugs.openjdk.java.net/browse/JDK-8221734
>>>
>>> Passes t1-7 and multiple t1-5 runs.
>>>
>>> A few startup benchmark see a small speedup.
>>>
>>> Thanks, Robbin
>