RFR: 8062247: Allow WhiteBox test to access JVM offsets

[Yumin Qi]

Misha,

   Thanks. The state transition is needed, we are in vm state, will call 
JNI, that is native state, or the assertion will tell us that.

Yumin

On 10/28/2014 9:32 AM, Mikhailo Seledtsov wrote:
> Hi Yumin,
>
>  The code looks good to me.
> One minor comment: could you add explanation comment why we are using 
> "ThreadToNativeFromVM ttnfv(thread);"? (no need for reposting webrev).
>
> Thank you,
> Misha
>
> On 10/27/2014 9:01 PM, Yumin Qi wrote:
>> Please review
>>
>> bug: https://bugs.openjdk.java.net/browse/JDK-8062247
>> webrev: http://cr.openjdk.java.net/~minqi/8062247/webrev00/
>>
>> Summary: Internal test failed since the variable offsets changed in 
>> hotspot. The way to get offset in the test is hard-coded. To reduce 
>> the risk of future changes of hotspot offsets, the fix add a WhiteBox 
>> API function to get a map for FileMapHeaderInfo, which return the 
>> members' offsets in a Hashtable.
>>
>> Tests: JPRT, jtreg.
>>
>> Thanks
>> Yumin
>