On Wed, Jun 13, 2018 at 09:47:44AM +0200, Thomas Hellstrom wrote: > ----- > > +The algorithm (Wait-Die vs Wound-Wait) is chosen using the _is_wait_die > +argument to DEFINE_WW_CLASS(). As a rough rule of thumb, use Wound-Wait iff you > +typically expect the number of simultaneous competing transactions to be small, > +and the rollback cost can be substantial. > + > Three different ways to acquire locks within the same w/w class. Common > definitions for methods #1 and #2: > > -static DEFINE_WW_CLASS(ww_class); > +static DEFINE_WW_CLASS(ww_class, false); Minor nit on the api here. Having a "flag" is a royal pain. You have to go and look up exactly what that "true/false" means every time you run across it in code to figure out what it means. Don't do that if at all possible. Make a new api: DEFINE_WW_CLASS_DIE(ww_class); instead that then wraps that boolean internally to switch between the different types. That way the api is "self-documenting" and we all know what is going on without having to dig through a header file. thanks, greg k-h
