[PATCH v4 09/12] powerpc/mm: replace batch->active with in_lazy_mmu_mode()

[Kevin Brodsky]

On 03/11/2025 16:05, David Hildenbrand wrote:
> On 29.10.25 11:09, Kevin Brodsky wrote:
>> A per-CPU batch struct is activated when entering lazy MMU mode; its
>> lifetime is the same as the lazy MMU section (it is deactivated when
>> leaving the mode). Preemption is disabled in that interval to ensure
>> that the per-CPU reference remains valid.
>>
>> The generic lazy_mmu layer now tracks whether a task is in lazy MMU
>> mode. We can therefore use the generic helper in_lazy_mmu_mode()
>> to tell whether a batch struct is active instead of tracking it
>> explicitly.
>>
>> Signed-off-by: Kevin Brodsky <kevin.brodsky at arm.com>
>> ---
>
> I suspect you were not able to test this on real HW. Some help from
> the ppc folks would be appreciated.

Indeed, it would be nice to get some testing on ppc HW that actually
uses lazy MMU (!radix_enabled()).

>
> LGTM, but the interaction with pause/resume adds a bit of complication
> on top.

Does it? This series doesn't change when arch_enter() and arch_leave()
are called, batch->active and in_lazy_mmu_mode() should coincide. 

- Kevin