Display function name in status-line

Which Function Mode should help you :

WhichFuncMode (also known as WhichFunctionMode) is a minor mode, that when activated displays the current function name in the mode line. It works under certain major modes, like CcMode or PerlMode.

To activate this minor mode : M-x which-function-mode RET

An interesting effect of this mode is by middle-clicking on the current function name : it can narrow the display to the current function.

OK... I found it: the mode is built in and can be globally activated by:

(which-function-mode 1)

Change colors and add major modes (e.g. org-mode is not enabled by default) with:

M-x customize-group and selecting which-func