On Tue 27-11-18 07:50:08, William Kucharski wrote: > > > > On Nov 27, 2018, at 6:17 AM, Michal Hocko <mhocko@xxxxxxxxxx> wrote: > > > > This is only about the process wide flag to disable THP. I do not see > > how this can be alighnement related. I suspect you wanted to ask in the > > smaps patch? > > No, answered below. > > > > >> I'm having to deal with both these issues in the text page THP > >> prototype I've been working on for some time now. > > > > Could you be more specific about the issue and how the alignment comes > > into the game? The only thing I can think of is to not report VMAs > > smaller than the THP as eligible. Is this what you are looking for? > > Basically, if the faulting VA is one that cannot be mapped with a THP > due to alignment or size constraints, it may be "eligible" for THP > mapping but ultimately can't be. > > I was just double checking that this was meant to be more of a check done > before code elsewhere performs additional checks and does the actual THP > mapping, not an all-encompassing go/no go check for THP mapping. I am still not sure I follow you completely here. This just reports per-task eligibility. The system wide eligibility is reported via sysfs and the per vma eligibility is reported via /proc/<pid>/smaps. -- Michal Hocko SUSE Labs
