  We discuss a method based on Killing symmetries and Komar conserved charges
to generalize Smarr mass formula for arbitrary dimensional charged, rotating
spacetime. We derive a local identity defined at the event horizon of the
rotating black hole in Einstein-Maxwell gravity which reproduces the
generalized Smarr formula as a by-product. The advantages of this new identity
are the following: (i) unlike Smarr formula, which is non-local, this identity
is purely local and hence a switchover between horizon and infinity is
unnecessary and (ii) the new identity could be mapped with the recent
investigations on emergent gravity.
