Re: [PATCH 3/4] mm/memory: convert do_shared_fault() to folios

[Sidhartha Kumar]

On 7/3/23 4:31 PM, Matthew Wilcox wrote:
> On Sun, Jul 02, 2023 at 10:58:49PM -0700, Sidhartha Kumar wrote:
> > Saves three implicit calls to compound_head().
> >
> > Signed-off-by: Sidhartha Kumar <sidhartha.kumar@xxxxxxxxxx>
> > ---
> >   mm/memory.c | 9 +++++----
> >   1 file changed, 5 insertions(+), 4 deletions(-)
> >
> > diff --git a/mm/memory.c b/mm/memory.c
> > index 93480e846ace6..33bf13431974c 100644
> > --- a/mm/memory.c
> > +++ b/mm/memory.c
> > @@ -4594,6 +4594,7 @@ static vm_fault_t do_shared_fault(struct vm_fault *vmf)
> >   {
> >   	struct vm_area_struct *vma = vmf->vma;
> >   	vm_fault_t ret, tmp;
> > +	struct folio *folio = page_folio(vmf->page);
>
> You can't call page_folio() until after __do_fault().  Did you test this
> series?

I thought it would be straightforward enough without testing but I 
didn't realize the initialization in __do_fault(). I will test and 
incorporate the other suggestions for a v2.

Thanks
> >   	ret = __do_fault(vmf);
> >   	if (unlikely(ret & (VM_FAULT_ERROR | VM_FAULT_NOPAGE | VM_FAULT_RETRY)))