Re: [PATCH RESEND 0/8] hugetlb: add demote/split page functionality

[Andrew Morton]

On Mon, 16 Aug 2021 17:17:50 -0700 Mike Kravetz <mike.kravetz@xxxxxxxxxx> wrote:

> > 
> > And how does one know the operation has completed so the sysfs files
> > can be reloaded for another operation?
> > 
> 
> When the write to the file is complete, the operation has completed.
> Not exactly sure what you mean by reloading the sysfs files for
> another operation?

If userspace wishes to perform another demote operation, it must wait
for the preceding one to complete.

Presumably if thread A is blocked in a write to `demote' and thread B
concurrently tries to perform a demotion, thread B will be blocked as
well?  Was this tested?

Lots of things are to be added to changelogs & documentation, methinks.