Re: [RFC PATCH 4/8] mm: Provide mm_struct and address to huge_ptep_get()

[Christophe Leroy <christophe.leroy@csgroup.eu>]

Le 25/03/2024 à 17:35, Jason Gunthorpe a écrit :
> On Mon, Mar 25, 2024 at 03:55:57PM +0100, Christophe Leroy wrote:
> 
>>   arch/arm64/include/asm/hugetlb.h |  2 +-
>>   fs/hugetlbfs/inode.c             |  2 +-
>>   fs/proc/task_mmu.c               |  8 +++---
>>   fs/userfaultfd.c                 |  2 +-
>>   include/asm-generic/hugetlb.h    |  2 +-
>>   include/linux/swapops.h          |  2 +-
>>   mm/damon/vaddr.c                 |  6 ++---
>>   mm/gup.c                         |  2 +-
>>   mm/hmm.c                         |  2 +-
>>   mm/hugetlb.c                     | 46 ++++++++++++++++----------------
>>   mm/memory-failure.c              |  2 +-
>>   mm/mempolicy.c                   |  2 +-
>>   mm/migrate.c                     |  4 +--
>>   mm/mincore.c                     |  2 +-
>>   mm/userfaultfd.c                 |  2 +-
>>   15 files changed, 43 insertions(+), 43 deletions(-)
>>
>> diff --git a/arch/qarm64/include/asm/hugetlb.h b/arch/arm64/include/asm/hugetlb.h
>> index 2ddc33d93b13..1af39a74e791 100644
>> --- a/arch/arm64/include/asm/hugetlb.h
>> +++ b/arch/arm64/include/asm/hugetlb.h
>> @@ -46,7 +46,7 @@ extern pte_t huge_ptep_clear_flush(struct vm_area_struct *vma,
>>   extern void huge_pte_clear(struct mm_struct *mm, unsigned long addr,
>>   			   pte_t *ptep, unsigned long sz);
>>   #define __HAVE_ARCH_HUGE_PTEP_GET
>> -extern pte_t huge_ptep_get(pte_t *ptep);
>> +extern pte_t huge_ptep_get(struct mm_struct *mm, unsigned long addr, pte_t *ptep);
> 
> The header changed but not the implementation? This will need to do
> riscv and s390 too.

It is now fixed.

> 
> Though, really, I think the right path is to work toward removing
> huge_ptep_get() from the arch code..
> 
> riscv and arm are doing the same thing - propogating dirty/young bits
> from the contig PTEs to the results. The core code can do this, maybe
> with a ARCH #define opt in.
> 
> s390.. Ouchy - is this because hugetlb wants to pretend that every
> level is encoded as a PTE so it takes the PGD and recodes the flags to
> the PTE layout??
> 
> Jason