She's a true professional!

Katy Perry didn't let her breakup with John Mayer stop her from premiering her new movie Katy Perry Prismatic World Tour last night in downtown L.A., and the singer was greeted by hoards of fans clamoring to get pics and autographs with the pop star.

The chart topper recently split with her Georgia-born beau, but she doesn't seem that upset about it. The womanizing musician and the "Fireworks" songstress previously broke up because of their hectic schedules, but this time around the notorious lothario is simply over it! There was a "lack of emotional interest on his end" and he was telling friends he "fell out of love with Perry but will always love her," a source dished to E! Online.

She's better off without her d-bag former lover anyways!