> Right. I missed that. I think we can use the page passed to rescue_unmovable_pageblock.
> We make sure it's valid in isolate_freepages. So how about this?
>
> barrios@bbox:~/linux-2.6$ git diff
> diff --git a/mm/compaction.c b/mm/compaction.c
> index 4ac338a..7459ab5 100644
> --- a/mm/compaction.c
> +++ b/mm/compaction.c
> @@ -368,11 +368,11 @@ isolate_migratepages_range(struct zone *zone, struct compact_control *cc,
> static bool rescue_unmovable_pageblock(struct page *page)
> {
> unsigned long pfn, start_pfn, end_pfn;
> - struct page *start_page, *end_page;
> + struct page *start_page, *end_page, *cursor_page;
>
> pfn = page_to_pfn(page);
> start_pfn = pfn & ~(pageblock_nr_pages - 1);
> - end_pfn = start_pfn + pageblock_nr_pages;
> + end_pfn = start_pfn + pageblock_nr_pages - 1;
>
> start_page = pfn_to_page(start_pfn);
> end_page = pfn_to_page(end_pfn);
> @@ -381,19 +381,19 @@ static bool rescue_unmovable_pageblock(struct page *page)
> if (page_zone(start_page) != page_zone(end_page))
> return false;
>
> - for (page = start_page, pfn = start_pfn; page < end_page; pfn++,
> - page++) {
> + for (cursor_page = start_page, pfn = start_pfn; cursor_page <= end_page; pfn++,
> + cursor_page++) {
> if (!pfn_valid_within(pfn))
> continue;
I guess page_zone() should be used after pfn_valid_within(). Why can
we assume invalid
pfn return correct zone?
> - if (PageBuddy(page)) {
> - int order = page_order(page);
> + if (PageBuddy(cursor_page)) {
> + int order = page_order(cursor_page);
>
> pfn += (1 << order) - 1;
> - page += (1 << order) - 1;
> + cursor_page += (1 << order) - 1;
>
> continue;
> - } else if (page_count(page) == 0 || PageLRU(page))
> + } else if (page_count(cursor_page) == 0 || PageLRU(cursor_page))
> continue;
>
> return false;
--
To unsubscribe, send a message with 'unsubscribe linux-mm' in
the body to majordomo@xxxxxxxxx. For more info on Linux MM,
see: http://www.linux-mm.org/ .
Fight unfair telecom internet charges in Canada: sign http://stopthemeter.ca/
Don't email: <a href