mm/compaction: use correct list in move_freelist_{head}/{tail}

Patch series "Fixes and cleanups to compaction", v3.

This is a series to do fix and clean up to compaction.
Patch 1-2 fix and clean up freepage list operation.
Patch 3-4 fix and clean up isolation of freepages
Patch 7 factor code to check if compaction is needed for allocation order.

More details can be found in respective patches. 


This patch (of 6):

The freepage is chained with buddy_list in freelist head. Use buddy_list
instead of lru to correct the list operation.

Link: https://lkml.kernel.org/r/20230901155141.249860-1-shikemeng@huaweicloud.com
Link: https://lkml.kernel.org/r/20230901155141.249860-2-shikemeng@huaweicloud.comSigned-off-by: Kemeng Shi <shikemeng@huaweicloud.com>
Reviewed-by: Baolin Wang <baolin.wang@linux.alibaba.com>
Acked-by: Mel Gorman <mgorman@techsingularity.net>
Cc: David Hildenbrand <david@redhat.com>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

mm/compaction.c

@@ -1395,8 +1395,8 @@ move_freelist_head(struct list_head *freelist, struct page *freepage)
 {
 	LIST_HEAD(sublist);
 
-	if (!list_is_last(freelist, &freepage->lru)) {
-		list_cut_before(&sublist, freelist, &freepage->lru);
+	if (!list_is_last(freelist, &freepage->buddy_list)) {
+		list_cut_before(&sublist, freelist, &freepage->buddy_list);
 		list_splice_tail(&sublist, freelist);
 	}
 }
@@ -1412,8 +1412,8 @@ move_freelist_tail(struct list_head *freelist, struct page *freepage)
 {
 	LIST_HEAD(sublist);
 
-	if (!list_is_first(freelist, &freepage->lru)) {
-		list_cut_position(&sublist, freelist, &freepage->lru);
+	if (!list_is_first(freelist, &freepage->buddy_list)) {
+		list_cut_position(&sublist, freelist, &freepage->buddy_list);
 		list_splice_tail(&sublist, freelist);
 	}
 }