Re: [PATCH v6 2/2] perf/x86/amd/power: Add AMD accumulated power reporting mechanism

[Huang Rui <ray.huang@amd.com>]

On Thu, Mar 03, 2016 at 06:57:53PM +0100, Thomas Gleixner wrote:
> On Fri, 4 Mar 2016, Huang Rui wrote:
> > On Thu, Mar 03, 2016 at 04:26:46PM +0100, Thomas Gleixner wrote:
> > > Why? You do a full for_each_online_cpu(i) loop after that, which does
> > > exactly the same thing, right?
> > >  
> > 
> > But looks like power_cpu_init cannot handle it if we don't take any
> > action here.
> > 
> > e. g. 
> > cpu_mask: 0000 and online mask: 1111 -> power_cpu_init(0) -> cpu_mask is still: 0000
> > 
> > topology_sibling_cpumask(0): 0011
> > target: 1 (i. e. we cannot do cpumask_set_cpu(0, &cpu_mask))
> 
> Fair enough, but then you don't need the power_cpu_init() call at all.
> 
> But your loop does not cover anything beyond the first socket. So you need a
> separate init function which does:
> 
>    for_each_online_cpu(cpu) {
>    	target = cpumask_first(topology_sibling_cpumask(cpu));
> 	if (!cpumask_test_cpu(target, cpumask))
> 	   	cpumask_set_cpu(target, cpumask);
>    }	      
> 	   	

Looks good. Thanks Thomas. Will update it.

Rui