On Mon, 20 Sep 2021 13:35:29 GMT, Coleen Phillimore <cole...@openjdk.org> wrote:
>> Partition safepoint checking and nonchecking lock ranks. The nonchecking >> locks are always lower ranked than the safepoint checking locks because they >> cannot block. >> >> This moves some leaf locks to 'nosafepoint' rank and corrects relative >> ranking. >> >> Tested with tier1-6 and built and run tier1 tests with shenandoah locally. > > Coleen Phillimore has updated the pull request incrementally with one > additional commit since the last revision: > > Remove 'safepoint' rank, now unused. src/hotspot/share/runtime/mutex.hpp line 53: > 51: special = tty + 3, > 52: oopstorage = special + 3, > 53: nosafepoint = oopstorage + 6, Maybe add a comment below `nosafepoint` like: // A thread is not allowed to safepoint while holding a mutex whose // rank is nosafepoint or lower. Also, how about renaming the generic name `lock_types` to something specific like `standard_lock_ranks`? BTW, should we (in separate RFE) add a new enum `_safepoint_check_default`, so that this parameter can be omitted depending on the rank value (unless in places where you need to override it)? For one thing, I never understood which _safepoint_check_xxx I should have used when adding a new lock. I just randomly changed it until the JVM stops crashing. ------------- PR: https://git.openjdk.java.net/jdk/pull/5550
