Rihanna arrives at the 54th annual Grammy Awards in Los Angeles. (AP Photo/Chris Pizzello).Nicki Minaj performs during the 54th annual Grammy Awards (AP Photo/Matt Sayles).LL Cool J speaks onstage during the 54th annual Grammy Awards (AP Photo/Matt Sayles).Alicia Keys performs during the 54th annual Grammy Awards (AP Photo/Matt Sayles)Glen Campbell, The Band Perry and Blake Shelton perform onstage during the 54th annual Grammy Awards (AP Photo/Matt Sayles)Dave Grohl and the Foo Fighters perform during the 54th annual Grammy Awards (AP Photo/Matt Sayles)Dave Grohl and the Foo Fighters perform during the 54th annual Grammy Awards (AP Photo/Matt Sayles).Chris Brown performs at the 54th annual Grammy Awards (AP Photo/Chris Pizzello).Paris Hilton takes a photo from the audience during the 54th annual Grammy Awards (AP Photo/Chris Pizzello).Rusty Anderson, left, and Paul McCartney perform during the 54th annual Grammy Awards (AP Photo/Matt Sayles)Paul McCartney during the 54th annual Grammy Awards (AP Photo/Matt Sayles).

Nicki Minaj, right, and guest arrive at the 54th annual Grammy Awards (AP Photo/Chris Pizzello)Bruce Springsteen performs with Steven Van Zandt and Patti Scialfa at the 54th annual Grammy Awards (AP Photo/Matt Sayles).Bruce Springsteen performs during the 54th annual Grammy Awards (AP Photo/Matt Sayles).Katy Perry performs during the 54th annual Grammy Awards (AP Photo/Matt Sayles).Katy Perry performs during the 54th annual Grammy Awards (AP Photo/Matt Sayles).Adam Levine from the band Maroon 5 performs during the 54th annual Grammy Awards (AP Photo/Matt Sayles).Jennifer Hudson performs "I Will Always Love You" during the In Memoriam portion of the 54th annual Grammy Awards (AP Photo/Matt Sayles).Lady Gaga stands in the audience during the 54th annual Grammy Awards (AP Photo/Matt Sayles).Dave Grohl, left, and the band Foo Fighters accept the award for best rock performance for "Walk" during the 54th annual Grammy Awards (AP Photo/Matt Sayles).Dave Grohl, of Foo Fighters, accepts the award for hard rock metal performance during the 54th annual Grammy Awards (AP Photo/Matt Sayles).Adele accepts the award for record of the year for "Rolling in the Deep" during the 54th annual Grammy Awards (AP Photo/Matt Sayles).

Neil Portnow, president of the National Academy of Recording Arts and Sciences, arrives (AP Photo/Chris Pizzello).Adele poses backstage with her six awards at the 54th annual Grammy Awards (AP Photo/Mark J. Terrill).Justin Vernon, of Bon Iver, poses backstage with the award for best alternative music album for "Bon Iver" at the 54th annual Grammy Awards (AP Photo/Mark J. Terrill).Ryan Tedder poses backstage with the award for album of the year for "21" at the 54th annual Grammy Awards (AP Photo/Mark J. Terrill).Ryan Tedder poses backstage with the award for album of the year for "21" at the 54th annual Grammy Awards (AP Photo/Mark J. Terrill).

Wiz Khalifa, left, and Amber Rose arrive (AP Photo/Chris Pizzello).

Taylor Swift, left, and Neil Patrick Harris arrive (AP Photo/Chris Pizzello).

Rihanna performs during the 54th annual Grammy Awards (AP Photo/Matt Sayles).

Rihanna, left, and Chris Martin of the band Coldplay perform during the 54th annual Grammy Awards (AP Photo/Matt Sayles).

Joy Williams, left, and John Paul White, of musical group The Civil Wars, perform during the 54th annual Grammy Awards (AP Photo/Matt Sayles).

Nicki Minaj performs during the 54th annual Grammy Awards(AP Photo/Matt Sayles).

Nicki Minaj performs during the 54th annual Grammy Awards (AP Photo/Matt Sayles).

LL Cool J speaks onstage during the 54th annual Grammy Awards (AP Photo/Matt Sayles).

Alicia Keys performs during the 54th annual Grammy Awards (AP Photo/Matt Sayles)

Glen Campbell, The Band Perry and Blake Shelton perform onstage during the 54th annual Grammy Awards (AP Photo/Matt Sayles)

Dave Grohl and the Foo Fighters perform during the 54th annual Grammy Awards (AP Photo/Matt Sayles)

Dave Grohl and the Foo Fighters perform during the 54th annual Grammy Awards (AP Photo/Matt Sayles).

Chris Brown performs at the 54th annual Grammy Awards (AP Photo/Chris Pizzello).

Paris Hilton takes a photo from the audience during the 54th annual Grammy Awards (AP Photo/Chris Pizzello).

Rusty Anderson, left, and Paul McCartney perform during the 54th annual Grammy Awards (AP Photo/Matt Sayles)

Paul McCartney during the 54th annual Grammy Awards (AP Photo/Matt Sayles).

Bruce Springsteen performs with Steven Van Zandt and Patti Scialfa at the 54th annual Grammy Awards (AP Photo/Matt Sayles).