softirq argument

Hi all As an experiment, i am trying to use softirq instead of using tasklet in my driver code. I was passing the driver's structure pointer to the tasklet. The "open_softirq" takes only the function pointer as argument. Since we can't pass any argument to the softirq, is there any workaround that is possible to make the structure pointer accessible to softirq? I just need to do this for taking measurements. Thanks, mugunthan