Re: [PATCH 4/4] nohz: New option to force all CPUs in full dynticksrange

From: Paul Gortmaker
Date: Tue Apr 09 2013 - 09:22:48 EST


On 13-04-08 10:57 AM, Christoph Lameter wrote:
> I think we could simplify things quite a bit if we either
>
> 1. Add any cpus specified with nohz_full/extended=xxx to
> rcu_nocb. No check is then necessary anymore.
>
> or
>
> 2. Avoid the setting of cpus entirely? If full nohz mode is desired
> then pick one cpu (f.e. the first one or the one that is used for xtime
> updates) and then make all other cpus nohz. Set the affinity mask for the
> rcuoXXX threads to that cpu.

I can imagine people with multi socket systems wanting to have
a system partitioned with one "normal" core per physical socket,
for timekeeping, RCU threads, etc, but #2 would prevent that.

Paul.
--
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/