Loading...

XML

Word

Printable

The issues that caused the BACKOUT were solved with ~~JDK-8300915~~.
See also https://mail.openjdk.org/pipermail/hotspot-gc-dev/2023-January/041194.html
--
The stackwalks to keep alive oops of nmethods found on stack during G1 remark seem redundant as nmethod entry barriers do the job already: https://github.com/openjdk/jdk/blob/f26bd4e0e8b68de297a9ff93526cd7fac8668320/src/hotspot/share/gc/shared/barrierSetNMethod.cpp#L85

Objects in the constant pool of a nmethod are weakly referenced. So G1 requires nmethod entry barriers to conservatively keep alive the constant objects for SATB during concurrent marking (see https://bugs.openjdk.org/browse/JDK-8288970).

clones

JDK-8297487 G1 Remark: no need to keep alive oop constants of nmethods on stack

is blocked by

JDK-8300915 G1: incomplete SATB because nmethod entry barriers don't get armed

relates to

JDK-8299956 [BACKOUT] 8297487: G1 Remark: no need to keep alive oop constants of nmethods on stack

JDK-8288970 G1 does not keep weak nmethod oops alive

JDK-8290025 Remove the Sweeper

links to

Commit openjdk/jdk/2009dc2b

Review openjdk/jdk/12561

(2 links to)