mm/slub: create kmalloc 96 and 192 caches regardless cache size order

For SLAB the kmalloc caches needed to be created in ascending sizes in
order. However, the constraint is not necessary anymore because SLAB has
been removed and SLUB doesn't need to comply with the constraint. Thus,
kmalloc 96 and 192 caches can be created after the other size kmalloc
caches are created instead of checking every time to find their order to
be created. Also, this change could prevent engineers from being confused
by the removed constraint.

Signed-off-by: Hyunmin Lee <hyunminlr@gmail.com>
Co-developed-by: Jeungwoo Yoo <casionwoo@gmail.com>
Signed-off-by: Jeungwoo Yoo <casionwoo@gmail.com>
Co-developed-by: Sangyun Kim <sangyun.kim@snu.ac.kr>
Signed-off-by: Sangyun Kim <sangyun.kim@snu.ac.kr>
Cc: Hyeonggon Yoo <42.hyeyoo@gmail.com>
Cc: Gwan-gyeong Mun <gwan-gyeong.mun@intel.com>
Reviewed-by: Christoph Lameter <cl@linux.com>
Acked-by: David Rientjes <rientjes@google.com>
Signed-off-by: Vlastimil Babka <vbabka@suse.cz>

mm/slab_common.c

@@ -916,21 +916,16 @@ void __init create_kmalloc_caches(void)
 	 * Including KMALLOC_CGROUP if CONFIG_MEMCG_KMEM defined
 	 */
 	for (type = KMALLOC_NORMAL; type < NR_KMALLOC_TYPES; type++) {
+		/* Caches that are NOT of the two-to-the-power-of size. */
+		if (KMALLOC_MIN_SIZE <= 32 && !kmalloc_caches[type][1])
+			new_kmalloc_cache(1, type);
+		if (KMALLOC_MIN_SIZE <= 64 && !kmalloc_caches[type][2])
+			new_kmalloc_cache(2, type);
+
+		/* Caches that are of the two-to-the-power-of size. */
 		for (i = KMALLOC_SHIFT_LOW; i <= KMALLOC_SHIFT_HIGH; i++) {
 			if (!kmalloc_caches[type][i])
 				new_kmalloc_cache(i, type);
-
-			/*
-			 * Caches that are not of the two-to-the-power-of size.
-			 * These have to be created immediately after the
-			 * earlier power of two caches
-			 */
-			if (KMALLOC_MIN_SIZE <= 32 && i == 6 &&
-					!kmalloc_caches[type][1])
-				new_kmalloc_cache(1, type);
-			if (KMALLOC_MIN_SIZE <= 64 && i == 7 &&
-					!kmalloc_caches[type][2])
-				new_kmalloc_cache(2, type);
 		}
 	}
 #ifdef CONFIG_RANDOM_KMALLOC_CACHES