Hi Wladimir Lopes.
We have two sentences: All up in my face business and All up in my grill
(1) Literal Meaning: All up in my grill doesn't necessarily mean to be in someone's business.
Although it is very odd, it means there is someone in your face.
(2) Slang: Therefore, it can also be used to describe someone / something which is excessively annoying and bothering you.
That ho was all up in my grill. Tell him to get his nasty, annoying self outta my face.
Sources: (1) LOVELY, Lutishia. All Up in my Business. Page 155. Kensington Publishing; 2011.
(2) PECKHAM, Aaron. Urban Dictionary - Book 3: Freshest Street Slang Defined. Andrews McMeel Publishing; 2012.