On Wed, 20 Nov 2024 00:13:13 GMT, William Kemper <wkem...@openjdk.org> wrote:
>> src/hotspot/share/gc/shenandoah/shenandoahBarrierSet.inline.hpp line 420:
>>
>>> 418: }
>>> 419: int gc_state = _heap->gc_state();
>>> 420: if ((gc_state & ShenandoahHeap::YOUNG_MARKING) != 0) {
>>
>> It is not very clear this works fine with single-gen mode. Does `MARKING`
>> imply `YOUNG_MARKING` in single-gen mode? I think we better make it
>> abundantly clear with `is_generational()` checks.
>
> Yes, in single gen mode we set `MARKING` and `YOUNG_MARKING` together. See
> https://github.com/openjdk/shenandoah/blob/master/src/hotspot/share/gc/shenandoah/shenandoahGlobalGeneration.cpp#L81
We should really either predicate it on generational mode (we already poll it a
few lines below) and check for `MARKING` specifically, or assert it.
-------------
PR Review Comment: https://git.openjdk.org/jdk/pull/21273#discussion_r1852659199
