In general, Bergevin's not into giving long term deals to older players. Petry will be 34 on Dec. 9th of the first year of his new contract.
He made an exception to get Weber, and that appears to be about to backfire.
But Petry is a good skater. Maybe he'll make an exception. If he decides he doesn't want to re-sign him, I expect him to trade him before he hits the open market, as he did with Pacioretty. I have a feeling if he does get traded it will be the summer before he becomes a UFA.
Hopefully Juulsen, Brook, and Fleury will all be showing good things already by next year, and he won't feel obliged to gamble on giving him a long term deal into his later 30's.