Messages in this thread Patch in this message | | | Subject | Re: [PATCH 3/3] reuse __free_pages_exact() in __alloc_pages_exact() | Date | Tue, 12 Apr 2011 17:57:23 +0200 | From | "Michal Nazarewicz" <> |
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On Tue, 12 Apr 2011 17:24:24 +0200, Dave Hansen <dave@linux.vnet.ibm.com> wrote:
> On Tue, 2011-04-12 at 12:29 +0200, Michal Nazarewicz wrote: >> On Tue, 12 Apr 2011 00:03:48 +0200, Dave Hansen >> <dave@linux.vnet.ibm.com> >> wrote: >> > diff -puN mm/page_alloc.c~reuse-free-exact mm/page_alloc.c >> > --- linux-2.6.git/mm/page_alloc.c~reuse-free-exact 2011-04-11 >> > 15:01:17.701822598 -0700 >> > +++ linux-2.6.git-dave/mm/page_alloc.c 2011-04-11 15:01:17.713822594 >> > -0700 >> > @@ -2338,14 +2338,11 @@ struct page *__alloc_pages_exact(gfp_t g >> > page = alloc_pages(gfp_mask, order); >> > if (page) { >> > - struct page *alloc_end = page + (1 << order); >> > - struct page *used = page + nr_pages; >> > + struct page *unused_start = page + nr_pages; >> > + int nr_unused = (1 << order) - nr_pages; >> >> How about unsigned long? > > Personally, I'd rather leave this up to the poor sucker that tries to > set MAX_ORDER to 33. If someone did that, we'd end up with kernels that > couldn't even boot on systems with less than 16GB of RAM since the > (required) flatmem mem_map[] would take up ~14.3GB. They couldn't > handle memory holes and couldn't be NUMA-aware, either.
I was thinking more about the fact that the int will get converted anyway when calling __free_pages_exact() and it makes no sense for number of pages to be negative. Just a suggestion, no strong feelings.
-- Best regards, _ _ .o. | Liege of Serenely Enlightened Majesty of o' \,=./ `o ..o | Computer Science, Michal "mina86" Nazarewicz (o o) ooo +-----<email/xmpp: mnazarewicz@google.com>-----ooO--(_)--Ooo--
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