mm,page_alloc: drop unnecessary checks from pfn_range_valid_contig

pfn_range_valid_contig() bails out when it finds an in-use page or a
hugetlb page, among other things.  We can drop the in-use page check since
__alloc_contig_pages can migrate away those pages, and the hugetlb page
check can go too since isolate_migratepages_range is now capable of
dealing with hugetlb pages.  Either way, those checks are racy so let the
end function handle it when the time comes.

Link: https://lkml.kernel.org/r/[email protected]
Signed-off-by: Oscar Salvador <[email protected]>
Suggested-by: David Hildenbrand <[email protected]>
Reviewed-by: David Hildenbrand <[email protected]>
Acked-by: Mike Kravetz <[email protected]>
Acked-by: Michal Hocko <[email protected]>
Cc: Muchun Song <[email protected]>
Cc: Vlastimil Babka <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>

1 files changed, 0 insertions, 6 deletions

diff --git a/mm/page_alloc.c b/mm/page_alloc.c
index 656f86a98554..80fa6e0f9ed9 100644
--- a/mm/page_alloc.c
+++ b/mm/page_alloc.c
@@ -8898,12 +8898,6 @@ static bool pfn_range_valid_contig(struct zone *z, unsigned long start_pfn,
 
 		if (PageReserved(page))
 			return false;
-
-		if (page_count(page) > 0)
-			return false;
-
-		if (PageHuge(page))
-			return false;
 	}
 	return true;
 }