[crac] RFR: Add Checkpoint timeout [v2]

[KIRIYAMA Takuya]

> Java process sometimes hangs when checkpoint for some reasons.
> For example, this problems occurs if you specify certain options for CRAC_CRIU_OPTS.
> 
> 
> # export CRAC_CRIU_OPTS=-V
> # java -XX:CRaCCheckpointTo=/work/cp CRACTest
> CR: Checkpoint ...
> 
> CRACTest process is not killed and is waiting for checkpoint.
> 
> 
> # ls /work/cp
> cppath  perfdata
> 
> 
> To avoid this problem, I want to add the checkpoint timeout.
> Can I submit a pull request to this repository? I would like you to review this change.

KIRIYAMA Takuya has updated the pull request incrementally with one additional commit since the last revision:

  Add checkpoint timepout

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

Changes:
  - all: https://git.openjdk.org/crac/pull/147/files
  - new: https://git.openjdk.org/crac/pull/147/files/f8c63468..c33a2772

Webrevs:
 - full: https://webrevs.openjdk.org/?repo=crac&pr=147&range=01
 - incr: https://webrevs.openjdk.org/?repo=crac&pr=147&range=00-01

  Stats: 1 line in 1 file changed: 0 ins; 0 del; 1 mod
  Patch: https://git.openjdk.org/crac/pull/147.diff
  Fetch: git fetch https://git.openjdk.org/crac.git pull/147/head:pull/147

PR: https://git.openjdk.org/crac/pull/147