On Tue, Mar 05, 2013 at 12:03:49PM +0100, Mike Belopuhov wrote: > On 5 March 2013 11:55, Mark Kettenis <mark.kette...@xs4all.nl> wrote: > >> Date: Tue, 5 Mar 2013 11:36:36 +0100 > >> From: Martin Pieuchot <mpieuc...@nolizard.org> > >> > >> The ifaddr structure contains a reference counter and two different way > >> to check it before freeing its memory: a macro IFAFREE(), and a function > >> ifafree(). > >> Because the former calls the latter when the reference counter is null, > >> and then also check for the reference counter, I see no point in keeping > >> two ways to do the same thing. > > > > Well, the point is probably that by doing the refcount check in the > > macro you avoid a function call in most cases. It's very well > > possible that this is a case of premature optimization. Almost > > certainly the case unless the macro is called in a > > performance-critical path. If it is called in a performance-critical > > path, some benchmarking should probably be done to make sure this > > doesn't impact something like packet forwarding performance in a > > negative way. > > > > to be fair, there are millions of these function calls. i highly > doubt one can measure any performance difference -- it'll all be > within error margin.
If we do IFAFREE() on a per packet basis then we do something wrong. Glancing at the diff I see no hot pathes that would matter. -- :wq Claudio
