Hi Richard, Unfortunately we have no plan for this activity. I’m not familiar with the problem so can’t estimate the time required to implement the functionality. Is this blocking you? As workaround I can prepare simple barriers implementation enough to run SerialGC.
With best regards, Sergey > On 28 Nov 2022, at 13:03, Reingruber, Richard <richard.reingru...@sap.com> > wrote: > > Dear ARM32 Maintainers, Boris, Sergey, [1] > > ARM32 does not implement nmethod entry barriers (see > https://bugs.openjdk.org/browse/JDK-8291302). > > This is actually a defect because nmethod entry barriers are a G1 requirement > where they are needed during concurrent marking to keep alive nmethod oop > constants as they are all weak oops[2]. > > I'd like to do a clean-up which removes redundant stackwalks from the G1 > remark pause[3]. With nmethod entry barriers they are not necessary as they > do the same keep alive for oop constants of nmethods found on stack. Without > nmethod barriers (ARM32) these stackwalks are not sufficient though as every > nmethod that is called during concurrent marking needs to do the keep alive > for SATB. > > Could you share your plans regarding the implementation of nmethod entry > barriers? How would you like me to handle ARM32 in the intended clean-up? > > Thanks, > Richard. > > [1] found you on https://wiki.openjdk.org/display/HotSpot/Ports > [2] https://bugs.openjdk.org/browse/JDK-8288970 > [3] https://github.com/openjdk/jdk/pull/11314