Re: [PATCH 12/14] sched: make dl_bw a sub-quota of rt_bw

From: Ingo Molnar
Date: Tue Oct 15 2013 - 09:11:43 EST



* Peter Zijlstra <peterz@xxxxxxxxxxxxx> wrote:

> On Tue, Oct 15, 2013 at 02:25:22PM +0200, Ingo Molnar wrote:
> >
> > Really, please make it _symmetric_ ...
> >
> > Single core systems are becoming a historic curiosity, should we
> > should justify every piece of extra complexity we add for them.
> >
> > So I'd rather see obvious SMP code where the UP case works fine too,
> > and _then_ maybe check a separate patch that adds the UP optimization,
> > with (object size) numbers proving that it's worth it, etc.
>
> That's a slightly larger task than it appears; the core scheduler code
> they rely on with smp doesn't exist on up.
>
> We can do this but we need to do it scheduler wide.

The scheduler has over 800 #ifdefs or similar preprocessor directives:

comet:~/tip> git grep '^#' kernel/sched/ | grep -v include | wc -l
855

I'd like to see this simplified a bit, _especially_ before we add new
complexity ...

Thanks,

Ingo
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/