Re: [PATCH] printk: use this_cpu_{read|write} api onprintk_pending

[Christoph Lameter]

On Fri, 26 Nov 2010, Eric Dumazet wrote:

> Le vendredi 26 novembre 2010 Ã 11:11 -0600, Christoph Lameter a Ãcrit :
>
> > I thought sanity tests do not apply for performance testing scenarios?
> >
>
> CONFIG_DEBUG_PREEMPT

You really enable that option for performance testing?

> > smp_processor_id() is usually a simple per cpu data access and very fast.
> >
>
> Sure, but when its already in a register, its better to use the
> register ;)

Well that increases register pressure in the caller. There may be no need
to handle the current processor number in the caller.