You are permitted, as a month to month tenant, to terminate the tenancy by giving at least 7 days written notice before the next rent payment is due.
If you wish to force the maintenance then you have a couple of options.
First, you can sue the landlord for breaching the tenancy by not providing maintenance to correct an issue, not you r fault, which makes the space unusable..
You can also, if the smell is traced to the restaurant, file a suit against the restaurant for nuisance and be awarded damages for the loss of the use and enjoyment of the leased premises.
You are not required to have an attorney to pursue either of these options, but, if you go to court, it is strongly recommended. If you need assistance finding local counsel try Martindale Hubble (site rules prohibit us from referring specific attorneys) . Many attorneys themselves use this site to locate attorneys outside their jurisdiction or expertise:
It is a huge worldwide database searchable by location and specialty. The attorneys are all peer rated. So, they represent the top of the profession.