Excerpts from Christophe Leroy's message of December 20, 2020 9:37 pm:
>
>
> Le 20/12/2020 à 00:48, Nicholas Piggin a écrit :
>> This allows the function to be entirely noped if hash support is
>> compiled out (not possible yet).
>>
>> Signed-off-by: Nicholas Piggin <npig...@gmail.com>
>> ---
>> arch/powerpc/include/asm/book3s/pgtable.h | 11 ++++++++++-
>> arch/powerpc/mm/book3s32/mmu.c | 4 ++--
>> arch/powerpc/mm/book3s64/hash_utils.c | 7 ++-----
>> 3 files changed, 14 insertions(+), 8 deletions(-)
>>
>> diff --git a/arch/powerpc/include/asm/book3s/pgtable.h
>> b/arch/powerpc/include/asm/book3s/pgtable.h
>> index 0e1263455d73..914e9fc7b069 100644
>> --- a/arch/powerpc/include/asm/book3s/pgtable.h
>> +++ b/arch/powerpc/include/asm/book3s/pgtable.h
>> @@ -35,7 +35,16 @@ extern pgprot_t phys_mem_access_prot(struct file *file,
>> unsigned long pfn,
>> * corresponding HPTE into the hash table ahead of time, instead of
>> * waiting for the inevitable extra hash-table miss exception.
>> */
>> -void update_mmu_cache(struct vm_area_struct *vma, unsigned long address,
>> pte_t *ptep);
>> +void hash__update_mmu_cache(struct vm_area_struct *vma, unsigned long
>> address, pte_t *ptep);
>> +
>> +static inline void update_mmu_cache(struct vm_area_struct *vma, unsigned
>> long address, pte_t *ptep)
>> +{
>> +#ifdef CONFIG_PPC64
>
> You shouldn't need that ifdef. radix_enabled() is always defined.
True, thanks.
>> + if (radix_enabled())
>> + return;
>> +#endif
>> + hash__update_mmu_cache(vma, address, ptep);
>> +}
>>
>> #endif /* __ASSEMBLY__ */
>> #endif
>> diff --git a/arch/powerpc/mm/book3s32/mmu.c b/arch/powerpc/mm/book3s32/mmu.c
>> index 859e5bd603ac..c5a570ca37ff 100644
>> --- a/arch/powerpc/mm/book3s32/mmu.c
>> +++ b/arch/powerpc/mm/book3s32/mmu.c
>> @@ -325,8 +325,8 @@ static void hash_preload(struct mm_struct *mm, unsigned
>> long ea)
>> *
>> * This must always be called with the pte lock held.
>> */
>> -void update_mmu_cache(struct vm_area_struct *vma, unsigned long address,
>> - pte_t *ptep)
>> +void hash__update_mmu_cache(struct vm_area_struct *vma, unsigned long
>> address,
>> + pte_t *ptep)
>
> Now the limit is 100 chars per line. This should fit on a single line I think.
I never quite know what to do here. The Linux limit is 100 but 80 is
still preferred AFAIK (e.g., don't make lots of lines beyond 80), but
80-100 can be used in some cases when splitting the line doesn't improve
readability on 80 colums.
This does (slightly) improve readability.
Thanks,
Nick
>
>> {
>> if (!mmu_has_feature(MMU_FTR_HPTE_TABLE))
>> return;
>> diff --git a/arch/powerpc/mm/book3s64/hash_utils.c
>> b/arch/powerpc/mm/book3s64/hash_utils.c
>> index 73b06adb6eeb..d52a3dee7cf2 100644
>> --- a/arch/powerpc/mm/book3s64/hash_utils.c
>> +++ b/arch/powerpc/mm/book3s64/hash_utils.c
>> @@ -1667,8 +1667,8 @@ static void hash_preload(struct mm_struct *mm, pte_t
>> *ptep, unsigned long ea,
>> *
>> * This must always be called with the pte lock held.
>> */
>> -void update_mmu_cache(struct vm_area_struct *vma, unsigned long address,
>> - pte_t *ptep)
>> +void hash__update_mmu_cache(struct vm_area_struct *vma, unsigned long
>> address,
>> + pte_t *ptep)
>
> Now the limit is 100 chars per line. This should fit on a single line I think.
>
>> {
>> /*
>> * We don't need to worry about _PAGE_PRESENT here because we are
>> @@ -1677,9 +1677,6 @@ void update_mmu_cache(struct vm_area_struct *vma,
>> unsigned long address,
>> unsigned long trap;
>> bool is_exec;
>>
>> - if (radix_enabled())
>> - return;
>> -
>> /* We only want HPTEs for linux PTEs that have _PAGE_ACCESSED set */
>> if (!pte_young(*ptep) || address >= TASK_SIZE)
>> return;
>>
>
