[PATCH v6 2/3] percpu: add PERCPU_ATOM_SIZE for a generic percpu area setup

[Christoph Lameter]

On Mon, 2 Nov 2015, Catalin Marinas wrote:

> I haven't looked at the patch 3/3 in detail but I'm pretty sure I'll NAK
> the approach (and the definition of PERCPU_ATOM_SIZE), therefore
> rendering this patch unnecessary. IIUC, this is used to enforce some
> alignment of the per-CPU IRQ stack to be able to check whether the
> current stack is process or IRQ on exception entry. But there are other,
> less intrusive ways to achieve the same (e.g. x86).

The percpu allocator allows the specification of alignment requirements.