X-Git-Url: http://git.cascardo.info/?a=blobdiff_plain;f=mm%2Fpage_alloc.c;h=c988d324e3f63f25aca5db4a735a2f7d137ec2de;hb=8348faf91f56371d4bada6fc5915e19580a15ffe;hp=a2214c64ed3cd04dceaed7a579f593852e458df1;hpb=3b495e4bf34b5e4ad2658e08694493e6068e2e5d;p=cascardo%2Flinux.git

diff --git a/mm/page_alloc.c b/mm/page_alloc.c
index a2214c64ed3c..c988d324e3f6 100644
--- a/mm/page_alloc.c
+++ b/mm/page_alloc.c
@@ -2489,9 +2489,14 @@ int __isolate_free_page(struct page *page, unsigned int order)
 	mt = get_pageblock_migratetype(page);
 
 	if (!is_migrate_isolate(mt)) {
-		/* Obey watermarks as if the page was being allocated */
-		watermark = low_wmark_pages(zone) + (1 << order);
-		if (!zone_watermark_ok(zone, 0, watermark, 0, 0))
+		/*
+		 * Obey watermarks as if the page was being allocated. We can
+		 * emulate a high-order watermark check with a raised order-0
+		 * watermark, because we already know our high-order page
+		 * exists.
+		 */
+		watermark = min_wmark_pages(zone) + (1UL << order);
+		if (!zone_watermark_ok(zone, 0, watermark, 0, ALLOC_CMA))
 			return 0;
 
 		__mod_zone_freepage_state(zone, -(1UL << order), mt);