On Tue, May 28, 2002 at 11:36:23PM -0700, Terry Lambert wrote: > Poul-Henning Kamp wrote: > > In message <[EMAIL PROTECTED]>, Peter Wemm writes: > > >As you said, _sleeping_ is the problem. M_WAITOK means "you may sleep if > > >you like". ie: it is a time bomb waiting for the right low memory condition > > >which will then explode with a 100% authentic crash or lock up. > > > > > >Pretend it said M_SLEEPOK instead of M_WAITOK. > > > > Uhm, I'm actually seeing the opposite behaviour as well: after I > > changed the md(4) driver to use M_NOWAIT I still see malloc/zalloc > > sleeping... > > I'm with Poul on this one, Peter: M_WAITOK doesn't mean what > you think it means: it's doesn't mean tsleep may be called, > and M_NOWAIT doesn't mean tsleep() _won't_ be called, in > practice.
With the same amount of time you spent typing up this Email, you could have checked the code and seen that M_WAITOK _does_ mean that tsleep may be called and that, in effect, M_NOWAIT means that tsleep will not be called. If we have cases where tsleep is called and are M_NOWAIT, then that's not good. M_NOWAIT means: "only allowed to block on a mutex." > It's either incredibly badly named, or it's incredibly badly > implemented -- I would argue the latter, actually, since even > if it's completely orthogonal, you're screwed because it means > you have two call conversion systems, without a WITNESS > intersection to detect deadly embraces. 8-(. > > -- Terry -- Bosko Milekic [EMAIL PROTECTED] [EMAIL PROTECTED] To Unsubscribe: send mail to [EMAIL PROTECTED] with "unsubscribe freebsd-current" in the body of the message
