Diddy called out DJ Whoo Kid in a big/funny/kinda serious way for going all Benedict Arnold on the vodka front.

Diddy was hosting a pool party at Hard Rock in Vegas Saturday when he came face-to-face with Whoo who was chugging the clear stuff, but not the right kind .. i.e., Ciroc.

Whoo was guzzling Belvedere, which kind of amused Diddy ... we think. As we reported, Diddy made more loot than any entertainer last year, so Whoo clearly knew what's up and traded bottles.