RFR(XS): 8204136: jtreg: Fix failing RTM test RTMSpinLoopCount

[Gustavo Romero]

Hi,

Could the following change be reviewed please?

webrev: http://cr.openjdk.java.net/~gromero/8204136/v1
bug   : https://bugs.openjdk.java.net/browse/JDK-8204136

It throttles down RTMSpinLoopCount deltas in TestRTMSpinLoopCount to avoid
a test timeout. Using current RTMSpinLoopCount values mostly makes the last
tries fail (RTMSpinLoopCount = 1_000_000 or 10_000_000). The proposed
increment is to make the next RTMSpinLoopCount value 10x greater than the
previous one.

Currently RTMSpinLoopCount can fail (error) sometimes due to timeout.
(Please see: http://cr.openjdk.java.net/~gromero/misc/moog_spincountloop_timeout.log)

The JVM behavior seems correct and indeed high RTMSpinLoopCount values
like 10_000_000 should take a long time to complete (> 2 minutes).

Thank you.


Best regards,
Gustavo