Re: [PATCH v3 3/8] mm/rmap: Split try_to_munlock from try_to_unmap

From: Alistair Popple
Date: Wed Mar 03 2021 - 23:28:56 EST


On Tuesday, 2 March 2021 3:10:49 AM AEDT Jason Gunthorpe wrote:
> > + while (page_vma_mapped_walk(&pvmw)) {
> > + /*
> > + * If the page is mlock()d, we cannot swap it out.
> > + * If it's recently referenced (perhaps page_referenced
> > + * skipped over this mm) then we should reactivate it.
> > + */
> > + if (vma->vm_flags & VM_LOCKED) {
>
> And since we write the data without holding the PTLs this looks
> pointless, unless there is some other VM_LOCKED manipulation
>

Thanks. I couldn't find any other manipulation of VM_LOCKED whilst holding the
PTL so I'll remove this redundant check.

- Alistair