X-Git-Url: http://plrg.eecs.uci.edu/git/?a=blobdiff_plain;f=mm%2Fzsmalloc.c;h=c1ea19478119f21afa1a3a2d27537c251f6c152d;hb=f8d4d71d8d22b39043c524e1d9f007bcd54bd2fa;hp=fc083996e40a6a1c7fb4116b1aecd3f40fab32c7;hpb=bddaf79195c4b9bae86b494fb6cfe855f8415afb;p=firefly-linux-kernel-4.4.55.git

diff --git a/mm/zsmalloc.c b/mm/zsmalloc.c
index fc083996e40a..c1ea19478119 100644
--- a/mm/zsmalloc.c
+++ b/mm/zsmalloc.c
@@ -1732,10 +1732,13 @@ static struct page *isolate_source_page(struct size_class *class)
 static unsigned long zs_can_compact(struct size_class *class)
 {
 	unsigned long obj_wasted;
+	unsigned long obj_allocated = zs_stat_get(class, OBJ_ALLOCATED);
+	unsigned long obj_used = zs_stat_get(class, OBJ_USED);
 
-	obj_wasted = zs_stat_get(class, OBJ_ALLOCATED) -
-		zs_stat_get(class, OBJ_USED);
+	if (obj_allocated <= obj_used)
+		return 0;
 
+	obj_wasted = obj_allocated - obj_used;
 	obj_wasted /= get_maxobj_per_zspage(class->size,
 			class->pages_per_zspage);