function::uaddr — User space address of current running task
uaddr:long()
Returns the address in userspace that the current
task was at when the probe occurred. When the current running task
isn't a user space thread, or the address cannot be found, zero
is returned. Can be used to see where the current task is combined
with usymname or usymdata. Often the task will be in the VDSO
where it entered the kernel.