Re: [PATCH 07/10] bootmem: add free_bootmem_late

[Chris Wright <chrisw@sous-sol.org>]

* Pekka Enberg (penberg@cs.helsinki.fi) wrote:
> On Mon, Nov 9, 2009 at 10:13 PM, Pekka Enberg <penberg@cs.helsinki.fi> wrote:
> >>        for (cursor = start; cursor < end; cursor += BITS_PER_LONG) {
> >> -               unsigned long idx, vec;
> >> +               unsigned long vec;
> >>
> >> -               idx = cursor - start;
> >> -               vec = ~map[idx / BITS_PER_LONG];
> >> +               if (map) {
> >> +                       unsigned long idx = cursor - start;
> >> +                       vec = ~map[idx / BITS_PER_LONG];
> >> +               } else {
> >> +                       if (end - cursor >= BITS_PER_LONG)
> >> +                               vec = ~0UL;
> >
> > Why do we need the above?
> 
> OK, I figured that out. I'm not sure why you want to play tricks with
> "vec" when you could just add a new helper that calls
> __free_pages_bootmem() for the full contiguous page range.

I did it this way since it's simple enough and allows for high-order
frees (these will nearly all be high-order) and keeps the same core
code exercised in each path.  You can't do a higher order free
w/ __free_pages_bootmem() w/out conforming to its requirements.
I don't care either way.

thanks,
-chris