RFR: Remove racy assert in ShenandoahResetNextMarkBitmapTraversalTask

[Aleksey Shipilev]

On 09/11/2018 11:21 PM, Roman Kennke wrote:
>> Seems to me ShenandoahResetNextBitmapTraversalTask should never experience trashed regions now.
>> Which means we can simplify it like below, and this will also solidify the expectation that trashed
>> regions recycling should happen before resetting the bitmaps:
>>   http://cr.openjdk.java.net/~shade/shenandoah/traversal-resetbitmaps-1.patch
>>
>> This passes tier3_gc_shenandoah on x86_64.
>>
>> -Aleksey
> 
> Good point!
> 
> The equivalent code in ShResetNextBitmapTask checks for
> is_bitmap_slice_committed(). Can this become a problem? Or is this
> something to be cleaned up there?

I wondered the same, but I think it is fine, because traversal bitmap reset variant only walks
traversal set, which is bound to be committed at that point. (I.e. traversal set never includes
uncommitted regions to begin with).

Thanks,
-Aleksey