a-foundation-benchmark/src/main/java/com/ajjpj/afoundation/concurrent/jdk/j9new/ForkJoinPool.java
final boolean tryExternalUnpush(ForkJoinTask<?> task) {
        WorkQueue[] ws; WorkQueue w; ForkJoinTask<?>[] a; int m, s;
        int r = ThreadLocalRandomHelper.getProbe();
        if ((ws = workQueues) != null && (m = ws.length - 1) >= 0 &&
            (w = ws[m & r & SQMASK]) != null &&
            (a = w.array) != null && (s = w.top) != w.base) {
            long j = (((a.length - 1) & (s - 1)) << ASHIFT) + ABASE;
            if (U.compareAndSwapInt(w, QLOCK, 0, 1)) {
                if (w.top == s && w.array == a &&
                    U.getObject(a, j) == task &&
                    U.compareAndSwapObject(a, j, task, null)) {
                    U.putOrderedInt(w, QTOP, s - 1);
                    U.putOrderedInt(w, QLOCK, 0);
                    return true;
                }
                U.compareAndSwapInt(w, QLOCK, 1, 0);
            }
        }
        return false;
    }
final boolean tryExternalUnpush(ForkJoinTask<?> task) {
        WorkQueue[] ws; WorkQueue w; ForkJoinTask<?>[] a; int m, s;
        int r = ThreadLocalRandomHelper.getProbe();
        if ((ws = workQueues) != null && (m = ws.length - 1) >= 0 &&
            (w = ws[m & r & SQMASK]) != null &&
            (a = w.array) != null && (s = w.top) != w.base) {
            long j = (((a.length - 1) & (s - 1)) << ASHIFT) + ABASE;
            if (U.compareAndSwapInt(w, QLOCK, 0, 1)) {
                if (w.top == s && w.array == a &&
                    U.getObject(a, j) == task &&
                    U.compareAndSwapObject(a, j, task, null)) {
                    U.putOrderedInt(w, QTOP, s - 1);
                    U.putOrderedInt(w, QLOCK, 0);
                    return true;
                }
                U.compareAndSwapInt(w, QLOCK, 1, 0);
            }
        }
        return false;
    }
Performs tryUnpush for an external submitter: Finds queue,
locks if apparently non-empty, validates upon locking, and
adjusts top. Each check can fail but rarely does.