> Greetings, > > Explicitly pin a virtual thread before acquiring the JFR string pool monitor > because migrating a carrier thread local event writer object onto another > carrier thread is impossible. > > During event commit, the thread is in a critical section because it has > loaded a carrier thread local event writer object. For virtual threads, a > contended monitor, such as a synchronized block, is a point where a thread > could become unmounted. > > A monitor guards the JFR string pool, but remounting a virtual thread onto > another carrier is impossible because of the event writer. > > Therefore, it's imperative to use explicit pin constructs to prevent > unmounting at this location. > > Testing: jdk_jfr > > Thanks > Markus
Markus Grönlund has updated the pull request incrementally with five additional commits since the last revision: - pin state conditional delivered using event writer object - Merge branch '8338417' of github.com:mgronlun/jdk into 8338417 - update test comment - hoist pinVirtualThread - 8338417 ------------- Changes: - all: https://git.openjdk.org/jdk/pull/20588/files - new: https://git.openjdk.org/jdk/pull/20588/files/2cf0c2cb..fc2a1b6e Webrevs: - full: https://webrevs.openjdk.org/?repo=jdk&pr=20588&range=04 - incr: https://webrevs.openjdk.org/?repo=jdk&pr=20588&range=03-04 Stats: 78 lines in 4 files changed: 48 ins; 11 del; 19 mod Patch: https://git.openjdk.org/jdk/pull/20588.diff Fetch: git fetch https://git.openjdk.org/jdk.git pull/20588/head:pull/20588 PR: https://git.openjdk.org/jdk/pull/20588
