How can I get "Completed" benchmarks?

In the Rails log, at the end of each request, I see stuff like:

Completed 200 OK in 921ms (Views: 1.0ms | ActiveRecord: 1.5ms)

How can I get to those elapsed times from my controller? I want to
record them, report them, analyze them, and stuff like that.

I found Controller#view_runtime (1.0ms in the example) and
Controller#db_runtime (1.5ms), but I can't find the total (921ms).

I've found a blog about getting such info from Mongrel, but I don't
think I'm using Mongrel (WeBrick in dev, Nginx in production, is there
still a mongrel in the house?) -- and SOMEBODY sure is collecting these
numbers, 'cause there they are in the logs!