Re: [PATCH] [request for inclusion] Realtime LSM

Arjan van de Ven
2005-01-07T14:27:46Z

On Fri, Jan 07, 2005 at 09:16:50AM -0500, Paul Davis wrote:
> >On Fri, Jan 07, 2005 at 07:56:02AM -0500, Paul Davis wrote:
> >> 2) this is *not* only about scheduling. Realtime tasks need
> >> mlockall() and/or mlock as well. even the man page for mlock
> >> recognizes this, yet almost all the discussion here has focused on
> >> scheduling.
> >
> >RLIMIT_MEMLOCK is your friend.
>
> rlimit_memlock limits the *amount* of memory that mlock() can be used
> on, not whether mlock can be used. at least, thats my understanding of
> the POSIX design for this. the man page and the source code for mlock
> support make that reasonably clear.

eh no. It defaults to zero, but if you increase it for a specific user, that
user is allowed to mlock more.

>
> Fine, we'll continue to tell people to use "realtime" LSM for audio
> work. The people this really affects probably won't use vanilla
> kernels anyway.

that is so not a constructive way to make progress.
The realtime LSM is the wrong concept. It's a hack to work around other
design issues with linux. *THAT* is what makes it wrong. Not the fact that
it wouldn't work (I believe it works, I don't think anyone doubts that
much). If you are unwilling to even discuss fixing the underlying design
issues then I'm scared that this issue will never come to any workable
solution.