  Given an L-space knot we show that its Upsilon function is the Legendre
transform of a counting function equivalent to the d-invariants of its large
surgeries. The unknotting obstruction obtained for the Upsilon function is, in
the case of L-space knots, contained in the d-invariants of large surgeries.
Generalizations apply for connected sums of L-space knots, which imply that the
slice obstruction provided by Upsilon on the subgroup of concordance generated
by L-space knots is no finer than that provided by the d-invariants.
