RFR(xs): 8221517: G1: Reserved page size for heap can be wrong

[sangheon.kim at oracle.com]

Hi all,

Can I have some reviews for the patch which fixes wrong G1 heap page 
size issue?

The page size which is used to decide G1 heap mapper comes from 
preferred page size or heap alignment. However, if it came from heap 
alignment, we have to limit to actual large page size if it is larger 
than large page size.

I added a new jtreg test to check this problem. It relies on the error 
message when printed if reserving memory with large page fails.
Unfortunately, Solaris has a bug that the error message is printed even 
in success. To address this problem I filed 'JDK-8221526: Solaris: large 
page reservation failure message is printed even in success.' and the 
test is excluded on Solaris.

CR: https://bugs.openjdk.java.net/browse/JDK-8221517
webrev: http://cr.openjdk.java.net/~sangheki/8221517/webrev.0
Testing: hs-tier1 ~ 5

Thanks,
Sangheon