On Sat, Dec 01, 2018 at 08:34:06AM +0800, Huang, Ying wrote: > Daniel Jordan <daniel.m.jordan@xxxxxxxxxx> writes: > > What do you think? > > I think that swapoff() which is the main user of try_to_unuse() isn't a > common operation in practical. So it's not necessary to make it more > complex for this. Ok, probably not worth the surgery on try_to_unuse, even if swapoff can be expensive when it does happen. > In alloc_hugepage_direct_gfpmask(), the only information provided by vma > is: vma->flags & VM_HUGEPAGE. Because we have no vma available, I think > it is OK to just assume that the flag is cleared. That is, rely on > system-wide THP settings only. > > What do you think about this proposal? Sounds like a good compromise. So alloc_hugepage_direct_gfpmask will learn to make 'vma' optional? Slightly concerned that future callers that should be passing vma's might not and open a way to ignore vma huge page hints, but probably not a big deal in practice.
