On Tue, 23 Dec 2025 17:06:30 GMT, Serguei Spitsyn <[email protected]> wrote:
> Please, review a simple fix for a jdk 26 regression: > [JDK-8364343](https://bugs.openjdk.org/browse/JDK-8364343). It will be pushed > to 27 first and then back ported to 26. > This issue impacts JVM TI scalability. The > [JDK-8364343](https://bugs.openjdk.org/browse/JDK-8364343) replaced the > overloaded ctor `MountUnmountDisabler(jthread thread)` with > `MountUnmountDisabler(oop thread_oop)`. This caused the most common JVM TI > pattern `MountUnmountDisabler disabler(thread)` (where thread is a jthread) > to be resolved to `MountUnmountDisabler(bool exclusive)`. It makes the > instantiated `MountUnmountDisabler` to disable `mount/unmount` transitions > for all virtual thread instead of the specific one. This problem was > identified with a minor tracing. > > The fix restores the original ctor `MountUnmountDisabler(jthread thread)`. > > Testing: > - TBD: run mach5 tiers 1-6 src/hotspot/share/runtime/mountUnmountDisabler.hpp line 59: > 57: > 58: public: > 59: MountUnmountDisabler(bool exlusive = false); In passing, exlusive -> exclusive ------------- PR Review Comment: https://git.openjdk.org/jdk/pull/28965#discussion_r2644936219
