Understanding the role of gluons inside the proton is an important task 
for both ongoing experiments and the future EIC. In this talk, 
I will present the first lattice-QCD result including that at physical pion mass for the gluon spin/helicity contribution
 in the proton, using a chiral fermion action. 
The first lattice result for the gluon total helicity $S_G$ in 
the $\overline{\text{MS}}$ scheme 10GeV^2 will also be presented, including 
a discussion of the general strategy and difficulties in the lattice calculations. 
This work has been highlighted as Viewpoint in PRL (https://journals.aps.org/prl/issues/118/10).