RFR 8251118: BiasedLocking::preserve_marks should not have a HandleMark

[Daniel D. Daugherty]

On 8/11/20 2:11 PM, Patricio Chilano wrote:
> Hi all,
>
> Please review the following small fix which involves removing the 
> added HandleMark in BiasedLocking::preserve_marks():
>
> Bug: https://bugs.openjdk.java.net/browse/JDK-8251118
> Webrev: http://cr.openjdk.java.net/~pchilanomate/8251118/v1/webrev/

src/hotspot/share/runtime/biasedLocking.cpp
     No comments.

As mentioned by Harold, adding a new test case to:

     test/hotspot/jtreg/runtime/7158988/FieldMonitor.java

that enables '-XX:+UseBiasedLocking' is a good idea.

Also, Coleen added this note to your bug report:

> Also in the patch for JDK-8249192 
> <https://bugs.openjdk.java.net/browse/JDK-8249192>, vframe.hpp 
> shouldn't include
> handles.inline.hpp (only cpp and inline.hpp files can include
> inline.hpp). It doesn't look like it needs handles.inline.hpp,
> only handles.hpp. 

Were you planning on resolving that left over in this bug?

Dan


>
> I've inspected the callers of BiasedLocking::preserve_marks() and they 
> all have an assert that the current thread is the VMThread. Since the 
> VMThread creates a HandleMark object before executing a VM operation 
> the extra HandleMark added in 8249192 is not needed.
> I've run tiers1-3 in mach5 with -XX:+UseBiasedLocking and without the 
> patch I get several crashes in BiasedLocking::restore_marks(). With 
> the patch tests completed successfully.
>
> Thanks,
> Patricio
>