usdt:$MMTK:mmtk:gc_start {
    if (@stats_enabled) {
        @gc_start_nsecs = nsecs;
    }
}

usdt:$MMTK:mmtk:gc_end {
    if (@stats_enabled) {
        @post_closure_time += nsecs - @post_closure_nsecs;
    }
}

usdt:$MMTK:mmtk:bucket_opened {
    if (@stats_enabled) {
        $ns = nsecs;
        // Please check enum WorkBucketStage for the numerical values of stages
        // Closure is 2 when vo_bit is not set
        if (arg0 == 2) {
            @closure_nsecs = $ns;
            @pre_closure_time += $ns - @gc_start_nsecs;
        }
        // Release is 14 when vo_bit is not set
        if (arg0 == 14) {
            @post_closure_nsecs = $ns;
            @closure_time += $ns - @closure_nsecs;
        }
    }
}