Re: alloc_pages_bulk

[Andrew Morton <akpm@zip.com.au>]

"Martin J. Bligh" wrote:
> 
> >>                 min += z->pages_min;
> >>                 if (z->free_pages > min) {
> >> -                       page = rmqueue(z, order);
> >> +                       page = rmqueue(z, order, count, pages);
> >
> > This won't compile because your rmqueue() no longer returns a
> > page pointer.
> 
> Arse. Will fix that in a second.

No rush.  Need to write some code which uses the interface
first...

> > d) Look at pages_min versus count before allocating any pages.  If
> >    the allocation of `count' pagess would cause ->free_pages to fall
> >    below min, then go run some reclaim _first_, and then go grab a
> >    number of pages.  That number is min(count, nr_pages_we_just_reclaimed).
> >    So the caller may see a partial result.
> >
> > I think d), yes?
> 
> I was under the impression I was already doing that by this bit at the
> start of the loop:
> 
> -       min = 1UL << order;
> +       min = count << order;
> 
> Is that sufficient already (obviously my returns from rmqueue are total crap,
> but other than that ... ;-))

Ah.  That'll work.

-
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