mm/zsmalloc: use class->objs_per_zspage to get num of max objects

num of max objects in zspage is stored in each size_class now.  So there
is no need to re-calculate it.

Link: http://lkml.kernel.org/r/1467882338-4300-3-git-send-email-opensource.ganesh@gmail.comSigned-off-by: Ganesh Mahendran <opensource.ganesh@gmail.com>
Acked-by: Minchan Kim <minchan@kernel.org>
Reviewed-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

mm/zsmalloc.c

@@ -635,8 +635,7 @@ static int zs_stats_size_show(struct seq_file *s, void *v)
 		freeable = zs_can_compact(class);
 		spin_unlock(&class->lock);
 
-		objs_per_zspage = get_maxobj_per_zspage(class->size,
-				class->pages_per_zspage);
+		objs_per_zspage = class->objs_per_zspage;
 		pages_used = obj_allocated / objs_per_zspage *
 				class->pages_per_zspage;
 
@@ -1014,8 +1013,7 @@ static void __free_zspage(struct zs_pool *pool, struct size_class *class,
 
 	cache_free_zspage(pool, zspage);
 
-	zs_stat_dec(class, OBJ_ALLOCATED, get_maxobj_per_zspage(
-			class->size, class->pages_per_zspage));
+	zs_stat_dec(class, OBJ_ALLOCATED, class->objs_per_zspage);
 	atomic_long_sub(class->pages_per_zspage,
 					&pool->pages_allocated);
 }
@@ -1366,7 +1364,7 @@ static bool can_merge(struct size_class *prev, int size, int pages_per_zspage)
 	if (prev->pages_per_zspage != pages_per_zspage)
 		return false;
 
-	if (get_maxobj_per_zspage(prev->size, prev->pages_per_zspage)
+	if (prev->objs_per_zspage
 		!= get_maxobj_per_zspage(size, pages_per_zspage))
 		return false;
 
@@ -1592,8 +1590,7 @@ unsigned long zs_malloc(struct zs_pool *pool, size_t size, gfp_t gfp)
 	record_obj(handle, obj);
 	atomic_long_add(class->pages_per_zspage,
 				&pool->pages_allocated);
-	zs_stat_inc(class, OBJ_ALLOCATED, get_maxobj_per_zspage(
-			class->size, class->pages_per_zspage));
+	zs_stat_inc(class, OBJ_ALLOCATED, class->objs_per_zspage);
 
 	/* We completely set up zspage so mark them as movable */
 	SetZsPageMovable(pool, zspage);
@@ -2265,8 +2262,7 @@ static unsigned long zs_can_compact(struct size_class *class)
 		return 0;
 
 	obj_wasted = obj_allocated - obj_used;
-	obj_wasted /= get_maxobj_per_zspage(class->size,
-			class->pages_per_zspage);
+	obj_wasted /= class->objs_per_zspage;
 
 	return obj_wasted * class->pages_per_zspage;
 }
@@ -2473,8 +2469,8 @@ struct zs_pool *zs_create_pool(const char *name)
 		class->size = size;
 		class->index = i;
 		class->pages_per_zspage = pages_per_zspage;
-		class->objs_per_zspage = class->pages_per_zspage *
-						PAGE_SIZE / class->size;
+		class->objs_per_zspage = get_maxobj_per_zspage(class->size,
+							class->pages_per_zspage);
 		spin_lock_init(&class->lock);
 		pool->size_class[i] = class;
 		for (fullness = ZS_EMPTY; fullness < NR_ZS_FULLNESS;