1 files changed, 11 insertions, 35 deletions

diff --git a/mm/shuffle.c b/mm/shuffle.c
index 44406d9977c7..9b5cd4b004b0 100644
--- a/mm/shuffle.c
+++ b/mm/shuffle.c
@@ -10,33 +10,11 @@
 #include "shuffle.h"
 
 DEFINE_STATIC_KEY_FALSE(page_alloc_shuffle_key);
-static unsigned long shuffle_state __ro_after_init;
-
-/*
- * Depending on the architecture, module parameter parsing may run
- * before, or after the cache detection. SHUFFLE_FORCE_DISABLE prevents,
- * or reverts the enabling of the shuffle implementation. SHUFFLE_ENABLE
- * attempts to turn on the implementation, but aborts if it finds
- * SHUFFLE_FORCE_DISABLE already set.
- */
-__meminit void page_alloc_shuffle(enum mm_shuffle_ctl ctl)
-{
-	if (ctl == SHUFFLE_FORCE_DISABLE)
-		set_bit(SHUFFLE_FORCE_DISABLE, &shuffle_state);
-
-	if (test_bit(SHUFFLE_FORCE_DISABLE, &shuffle_state)) {
-		if (test_and_clear_bit(SHUFFLE_ENABLE, &shuffle_state))
-			static_branch_disable(&page_alloc_shuffle_key);
-	} else if (ctl == SHUFFLE_ENABLE
-			&& !test_and_set_bit(SHUFFLE_ENABLE, &shuffle_state))
-		static_branch_enable(&page_alloc_shuffle_key);
-}
 
 static bool shuffle_param;
 static int shuffle_show(char *buffer, const struct kernel_param *kp)
 {
-	return sprintf(buffer, "%c\n", test_bit(SHUFFLE_ENABLE, &shuffle_state)
-			? 'Y' : 'N');
+	return sprintf(buffer, "%c\n", shuffle_param ? 'Y' : 'N');
 }
 
 static __meminit int shuffle_store(const char *val,
@@ -47,9 +25,7 @@ static __meminit int shuffle_store(const char *val,
 	if (rc < 0)
 		return rc;
 	if (shuffle_param)
-		page_alloc_shuffle(SHUFFLE_ENABLE);
-	else
-		page_alloc_shuffle(SHUFFLE_FORCE_DISABLE);
+		static_branch_enable(&page_alloc_shuffle_key);
 	return 0;
 }
 module_param_call(shuffle, shuffle_store, shuffle_show, &shuffle_param, 0400);
@@ -58,25 +34,25 @@ module_param_call(shuffle, shuffle_store, shuffle_show, &shuffle_param, 0400);
  * For two pages to be swapped in the shuffle, they must be free (on a
  * 'free_area' lru), have the same order, and have the same migratetype.
  */
-static struct page * __meminit shuffle_valid_page(unsigned long pfn, int order)
+static struct page * __meminit shuffle_valid_page(struct zone *zone,
+						  unsigned long pfn, int order)
 {
-	struct page *page;
+	struct page *page = pfn_to_online_page(pfn);
 
 	/*
 	 * Given we're dealing with randomly selected pfns in a zone we
 	 * need to ask questions like...
 	 */
 
-	/* ...is the pfn even in the memmap? */
-	if (!pfn_valid_within(pfn))
+	/* ... is the page managed by the buddy? */
+	if (!page)
 		return NULL;
 
-	/* ...is the pfn in a present section or a hole? */
-	if (!pfn_in_present_section(pfn))
+	/* ... is the page assigned to the same zone? */
+	if (page_zone(page) != zone)
 		return NULL;
 
 	/* ...is the page free and currently on a free_area list? */
-	page = pfn_to_page(pfn);
 	if (!PageBuddy(page))
 		return NULL;
 
@@ -123,7 +99,7 @@ void __meminit __shuffle_zone(struct zone *z)
 		 * page_j randomly selected in the span @zone_start_pfn to
 		 * @spanned_pages.
 		 */
-		page_i = shuffle_valid_page(i, order);
+		page_i = shuffle_valid_page(z, i, order);
 		if (!page_i)
 			continue;
 
@@ -137,7 +113,7 @@ void __meminit __shuffle_zone(struct zone *z)
 			j = z->zone_start_pfn +
 				ALIGN_DOWN(get_random_long() % z->spanned_pages,
 						order_pages);
-			page_j = shuffle_valid_page(j, order);
+			page_j = shuffle_valid_page(z, j, order);
 			if (page_j && page_j != page_i)
 				break;
 		}