RFR: 8284950: CgroupV1 detection code should consider memory.swappiness [v7]

[xpbob]

> set memory.swappiness to 0,swap space will not be used 
> determine the value of memory.swappiness
> https://www.kernel.org/doc/Documentation/cgroup-v1/memory.txt
> 
> 
>     Memory Limit: 50.00M
>     Memory Soft Limit: Unlimited
>     Memory & Swap Limit: 100.00M
>     Maximum Processes Limit: 4194305 
> 
> =>
> 
>     Memory Limit: 50.00M
>     Memory Soft Limit: Unlimited
>     Memory & Swap Limit: 50.00M
>     Maximum Processes Limit: 4194305

xpbob has updated the pull request incrementally with three additional commits since the last revision:

 - add test
 - add test
 - add cgroup v1 test

-------------

Changes:
  - all: https://git.openjdk.java.net/jdk/pull/8285/files
  - new: https://git.openjdk.java.net/jdk/pull/8285/files/9dd1bbf3..8c46be1c

Webrevs:
 - full: https://webrevs.openjdk.java.net/?repo=jdk&pr=8285&range=06
 - incr: https://webrevs.openjdk.java.net/?repo=jdk&pr=8285&range=05-06

  Stats: 305 lines in 4 files changed: 268 ins; 36 del; 1 mod
  Patch: https://git.openjdk.java.net/jdk/pull/8285.diff
  Fetch: git fetch https://git.openjdk.java.net/jdk pull/8285/head:pull/8285

PR: https://git.openjdk.java.net/jdk/pull/8285