Re: [PATCH 3/5] metag: smp: don't spin waiting for CPU to start

[Thomas Gleixner]

On Mon, 1 Jul 2013, James Hogan wrote:
> Use a completion to block until a secondary CPU has started up, like ARM
> do, instead of a loop of udelays.
> 
> On Meta, SMP is really SMT, with each "CPU" being a different hardware
> thread on the same Meta processor core, so as well as being more
> efficient and latency friendly, using a completion prevents the bogomips
> of the secondary CPU from being drastically skewed every time by the
> execution of the tight in-cache udelay loop on the other CPU.

The least of our worries is the correctness of bogomips. But if that
patch makes bogomips less bogus while fixing a real issue, please add
my
 
Acked-by: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
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