'Reservoir Dogs' -- REUNITED ... Mr. Brown, Mr. White and Mr. Orange

"Reservoir Dogs" stars Harvey Keitel and Tim Roth reunited with co-star/director Quentin Tarantino last night in France -- and not one person was shot.

It was all for an award being given to Q.T. at the Lumiere Film Festival in Lyon ... where both Keitel and Roth gave speeches during the presentation.

Last year was the 20th anniversary of "Dogs" ... and the movie is widely considered one of the best independent films of all time.

It's unclear if they were discussing the appropriate tipping amount.