Re: [this_cpu_xx V4 00/20] Introduce per cpu atomic operations and avoid per cpu address arithmetic

[Ingo Molnar <mingo@elte.hu>]

* Tejun Heo <tj@kernel.org> wrote:

> Hello,
> 
> cl@linux-foundation.org wrote:
> > V3->V4:
> > - Fix various macro definitions.
> > - Provider experimental percpu based fastpath that does not disable
> >   interrupts for SLUB.
> 
> The series looks very good to me. [...]

Seconded, very nice series!

One final step/cleanup seems to be missing from it: it should replace 
current uses of percpu_op() [percpu_read(), etc.] in the x86 tree and 
elsewhere with the new this_cpu_*() primitives. this_cpu_*() is using 
per_cpu_from_op/per_cpu_to_op directly, we dont need those percpu_op() 
variants anymore.

There should also be a kernel image size comparison done for that step, 
to make sure all the new primitives are optimized to the max on the 
instruction level.

> [...] percpu#for-next now has ia64 bits included and the legacy 
> allocator is gone there so it can carry this series.  Sans the last 
> one, they seem they can be stable and incremental from now on, right?  
> Shall I include this series into the percpu tree?

I'd definitely recommend doing that - it should be tested early and wide 
for v2.6.33, and together with other percpu bits.

	Ingo