[prev in list] [next in list] [prev in thread] [next in thread] 

List:       openjdk-hotspot-runtime-dev
Subject:    RFR(XXS): 8165018: Missing memory barrier for PPC64 in Unsafe_GetObjectVolatile
From:       "Doerr, Martin" <martin.doerr () sap ! com>
Date:       2016-08-30 10:51:27
Message-ID: ab13a573b75f451c83ff92e230613706 () DEWDFE13DE14 ! global ! corp ! sap
[Download RAW message or body]

Hi,

we found that a memory barrier for PPC64 is missing in the current Unsafe i=
mplementation. get_volatile already contains the memory barrier for "suppor=
t_IRIW_for_not_multiple_copy_atomic_cpu". The same is needed in Unsafe_GetO=
bjectVolatile.

Here's my webrev:
http://cr.openjdk.java.net/~mdoerr/8165018_UnsafePPC64/webrev.00/

And while looking at it I wonder why Unsafe_GetObjectVolatile does not cont=
ain a G1 barrier like Unsafe_GetObject. Is it not possible to use the Volat=
ile version to access the referent field of a Reference?

Please review. As it is shared code, I will need a sponsor, please.

Best regards,
Martin

[prev in list] [next in list] [prev in thread] [next in thread]