[PATCH 3/3] powerpc/mm/radix: Flush page walk cache when freeing page table

[Aneesh Kumar K.V]

Benjamin Herrenschmidt <benh at kernel.crashing.org> writes:

> On Thu, 2016-06-02 at 15:16 +0530, Aneesh Kumar K.V wrote:
>> 
>> 
>> +/*
>> + * flush the page walk cache for the address
>> + */
>> +void flush_tlb_pgtable(struct mmu_gather *tlb, unsigned long address)
>> +{
>> +       struct mm_struct *mm = tlb->mm;
>> +       /*
>> +        * flush the page table walk cache on freeing page table. We already
>> +        * have marked the upper/higher level page table entry none by now.
>> +        * So it is safe to flush PWC here.
>> +        */
>> +       if (!radix_enabled())
>> +               return;
>> +       radix__flush_tlb_mm_pwc(mm);
>
> That means that on hash, we pay the price of a useless function call
> and return. Shouldn't we put the radix_enabled() test in the caller
> instead ?
>

I wil convert that to static inline.

-aneesh