[PATCH] ARM: formalize an IPI for CPU wake-ups

[Russell King - ARM Linux]

On Mon, Jun 11, 2012 at 02:40:24PM -0400, Nicolas Pitre wrote:
> On Mon, 11 Jun 2012, Russell King - ARM Linux wrote:
> 
> > On Mon, Jun 11, 2012 at 01:18:28PM -0400, Nicolas Pitre wrote:
> > > And that message certainly has to go as it may be triggered multiple 
> > > times per second in some use cases here.
> > 
> > That, I interpret, as an attempt to use CPU hotplugging for power
> > saving.
> > 
> > No.  Do not do that.  Under any circumstances.  Not only is the CPU
> > hotplugging code racy in places, it also totally destroys the ability
> > to have threads bound to CPUs, or even interrupts to CPUs.
> 
> [ more comments ommitted ]
> 
> Russell, let me suggest you take the time to read this:
> 
> 	http://lwn.net/Articles/481055/
> 
> then let's restart this conversation if you please.

Same comments apply for exactly the reasons I stated.