Re: [PATCH 4/6] x86/cpufreq: use cpumask_copy instead of =

Yinghai Lu
2009-06-09T08:15:02Z

Rusty Russell wrote:
> On Sun, 7 Jun 2009 07:23:52 am Yinghai Lu wrote:
>
>> so later could use nr_cpumask_bits in cpumask_size when MAXSMP is used
>>
>
> I have a (more ambitious) patch for this in my queue, which weans it off this
> entirely:
>
> Subject: cpumask: avoid playing with cpus_allowed in powernow-k8.c
> From: Rusty Russell <rusty@rustcorp.com.au>
>
> It's generally a very bad idea to mug some process's cpumask: it could
> legitimately and reasonably be changed by root, which could break us
> (if done before our code) or them (if we restore the wrong value).
>
> I use work_on_cpu, which is slightly less efficient than the old code,
> but the code is complex enough that using smp_call_function_single()
> is not trivial.
>

will be in .31?

YH