Re: [PATCH v9 06/24] mm: make pte_unmap_same compatible with SPF

From: David Rientjes
Date: Wed Mar 28 2018 - 06:20:32 EST


On Wed, 28 Mar 2018, Laurent Dufour wrote:

> >> @@ -2913,7 +2921,8 @@ int do_swap_page(struct vm_fault *vmf)
> >> int exclusive = 0;
> >> int ret = 0;
> >
> > Initialization is now unneeded.
>
> I'm sorry, what "initialization" are you talking about here ?
>

The initialization of the ret variable.

@@ -2913,7 +2921,8 @@ int do_swap_page(struct vm_fault *vmf)
int exclusive = 0;
int ret = 0;

- if (!pte_unmap_same(vma->vm_mm, vmf->pmd, vmf->pte, vmf->orig_pte))
+ ret = pte_unmap_same(vmf);
+ if (ret)
goto out;

entry = pte_to_swp_entry(vmf->orig_pte);

"ret" is immediately set to the return value of pte_unmap_same(), so there
is no need to initialize it to 0.