RFR: 8269225: JFR.stop misses the written info when the filename is only specified by JFR.start

[Denghui Dong]

Hi,

Could I have a review of this small fix?

JFR.stop misses the written info when the filename is only specified by JFR.start, for example:

$jcmd 87802 JFR.start name=test filename=2.jfr
87802:
Started recording 1. No limit specified, using maxsize=250MB as default.

Use jcmd 87802 JFR.dump name=test to copy recording data to file.

$jcmd 87802 JFR.stop name=test
87802:
Stopped recording "test".


The 'JFR.stop' didn't print written info, but actually, 2.jfr was generated.

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Commit messages:
 - 8269225: JFR.stop misses the written info when the filename is only specified by JFR.start

Changes: https://git.openjdk.java.net/jdk/pull/4573/files
 Webrev: https://webrevs.openjdk.java.net/?repo=jdk&pr=4573&range=00
  Issue: https://bugs.openjdk.java.net/browse/JDK-8269225
  Stats: 6 lines in 1 file changed: 5 ins; 1 del; 0 mod
  Patch: https://git.openjdk.java.net/jdk/pull/4573.diff
  Fetch: git fetch https://git.openjdk.java.net/jdk pull/4573/head:pull/4573

PR: https://git.openjdk.java.net/jdk/pull/4573