Re: [PATCH V2] mm/mprotect: Add a cond_resched() inside change_pmd_range()

From: Michal Hocko
Date: Thu Dec 14 2017 - 06:29:34 EST


On Thu 14-12-17 16:44:26, Anshuman Khandual wrote:
> diff --git a/mm/mprotect.c b/mm/mprotect.c
> index ec39f73..43c29fa 100644
> --- a/mm/mprotect.c
> +++ b/mm/mprotect.c
> @@ -196,6 +196,7 @@ static inline unsigned long change_pmd_range(struct vm_area_struct *vma,
> this_pages = change_pte_range(vma, pmd, addr, next, newprot,
> dirty_accountable, prot_numa);
> pages += this_pages;
> + cond_resched();
> } while (pmd++, addr = next, addr != end);
>
> if (mni_start)

this is not exactly what I meant. See how change_huge_pmd does continue.
That's why I mentioned zap_pmd_range which does goto next...
--
Michal Hocko
SUSE Labs