Green’s Dictionary of Slang

what’s going on? phr.

a common greeting.

1957		H. Simmons Corner Boy 78: Hey, man [...] What’s going?
1974		(con. 1960s) R. Price Wanderers 19: ‘Hey, Richie!’ ‘Hey, babe, what’s goin’ on?’.
1999		Indep. Rev. 10 Aug. 7: The hair-gelled bucks who never get beyond [...] ‘Hey pal, what’s going on?’ in their conversations.
2002		‘Touré’ Portable Promised Land (ms.) 158: We Words (My Favorite Things) [...] Where ya at? What de deal? What’s goin on? What’s the dilly-o?