On Fri, 31 May 2024 14:24:56 GMT, Doug Lea <d...@openjdk.org> wrote: >> src/java.base/share/classes/java/util/concurrent/ForkJoinPool.java line 2024: >> >>> 2022: } >>> 2023: if (pb == (pb = b)) // base >>> unchanged >>> 2024: Thread.onSpinWait(); >> >> @DougLea Doesn't this mean that we'll always onSpinWait at least once here >> (since pb is initialized to -1 and not written until this check) > > No, almost the opposite: it only spinWaits if base is apparently stuck, > except (harmlessly) every 4B encounters when it happens to be -1. (The value > -1 works best here since base starts at 0 and is simpler than other ways of > checking for stalls.)
@DougLea You're right, I've seen too many of these consistency-checks to have my brain read "!=" automatically. Sorry for the noise :) ------------- PR Review Comment: https://git.openjdk.org/jdk/pull/19131#discussion_r1622520678
