Messages in this thread |  | | | Subject | Re: [PATCH 03/11] mm: mmzone: introduce zone_pfn_same_memmap() | | Date | Mon, 12 Dec 2011 15:35:03 +0100 | | From | "Michal Nazarewicz" <> |
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> On Fri, Nov 18, 2011 at 05:43:10PM +0100, Marek Szyprowski wrote: >> From: Michal Nazarewicz <mina86@mina86.com> >> diff --git a/mm/compaction.c b/mm/compaction.c >> index 6afae0e..09c9702 100644 >> --- a/mm/compaction.c >> +++ b/mm/compaction.c >> @@ -111,7 +111,10 @@ skip: >> >> next: >> pfn += isolated; >> - page += isolated; >> + if (zone_pfn_same_memmap(pfn - isolated, pfn)) >> + page += isolated; >> + else >> + page = pfn_to_page(pfn); >> }
On Mon, 12 Dec 2011 15:19:53 +0100, Mel Gorman <mel@csn.ul.ie> wrote: > Is this necessary? > > We are isolating pages, the largest of which is a MAX_ORDER_NR_PAGES > page. [...]
This is not true for CMA.
> That said, everywhere else managed to avoid checks like this by always > scanning in units of pageblocks. Maybe this should be structured > the same way to guarantee pfn_valid is called at least per pageblock > (even though only once per MAX_ORDER_NR_PAGES is necessary).
I'll look into that.
-- Best regards, _ _ .o. | Liege of Serenely Enlightened Majesty of o' \,=./ `o ..o | Computer Science, Michał “mina86” Nazarewicz (o o) ooo +----<email/xmpp: mpn@google.com>--------------ooO--(_)--Ooo-- -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
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