RFR (S): JDK-8057910: G1: BOT verification should not pass top

[Bengt Rutisson]

Thanks StefanK and Thomas for the quick reviews!

I'll push this directly now to get cleaner tests this night.

Thanks,
Bengt

On 2014-09-09 14:32, Thomas Schatzl wrote:
> Hi,
>
> On Tue, 2014-09-09 at 14:13 +0200, Bengt Rutisson wrote:
>> Hi all,
>>
>> Can I have a couple of reviews for this fix?
>>
>> http://cr.openjdk.java.net/~brutisso/8057910/webrev.00/
>>
>> https://bugs.openjdk.java.net/browse/JDK-8057910
>>
>>
>> After the fix for JDK-8025564 the BOT verification may pass the end for
>> the reserved space. The reason is this code in G1BlockOffsetArray::verify():
>>
>>     size_t start_card = _array->index_for(gsp()->bottom());
>>     size_t end_card = _array->index_for(gsp()->top());
>>
>> The end_card should not be based on top() but on "top() - 1" to make
>> sure we are inside the heap region and thus inside the reserved space.
>>
>> Testing:
>> - Ad hoc aurora tests simulating nightly testing. The current bug failed
>> a lot in the nightly testing.
>> - JPRT
>    looks good.
>
> Thomas
>
>