Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/penberg/slab-2.6

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/penberg/slab-2.6:
  slub: Do not use 192 byte sized cache if minimum alignment is 128 byte

2 files changed, 12 insertions, 2 deletions

diff --git a/include/linux/slub_def.h b/include/linux/slub_def.h
index 71e43a1..cef6f8f 100644
--- a/include/linux/slub_def.h
+++ b/include/linux/slub_def.h
@@ -137,10 +137,12 @@ static __always_inline int kmalloc_index(size_t size)
 	if (size <= KMALLOC_MIN_SIZE)
 		return KMALLOC_SHIFT_LOW;
 
+#if KMALLOC_MIN_SIZE <= 64
 	if (size > 64 && size <= 96)
 		return 1;
 	if (size > 128 && size <= 192)
 		return 2;
+#endif
 	if (size <=          8) return 3;
 	if (size <=         16) return 4;
 	if (size <=         32) return 5;
diff --git a/mm/slub.c b/mm/slub.c
index 0987d1c..2c9a62d 100644
--- a/mm/slub.c
+++ b/mm/slub.c
@@ -2995,8 +2995,6 @@ void __init kmem_cache_init(void)
 		create_kmalloc_cache(&kmalloc_caches[1],
 				"kmalloc-96", 96, GFP_KERNEL);
 		caches++;
-	}
-	if (KMALLOC_MIN_SIZE <= 128) {
 		create_kmalloc_cache(&kmalloc_caches[2],
 				"kmalloc-192", 192, GFP_KERNEL);
 		caches++;
@@ -3026,6 +3024,16 @@ void __init kmem_cache_init(void)
 	for (i = 8; i < KMALLOC_MIN_SIZE; i += 8)
 		size_index[(i - 1) / 8] = KMALLOC_SHIFT_LOW;
 
+	if (KMALLOC_MIN_SIZE == 128) {
+		/*
+		 * The 192 byte sized cache is not used if the alignment
+		 * is 128 byte. Redirect kmalloc to use the 256 byte cache
+		 * instead.
+		 */
+		for (i = 128 + 8; i <= 192; i += 8)
+			size_index[(i - 1) / 8] = 8;
+	}
+
 	slab_state = UP;
 
 	/* Provide the correct kmalloc names now that the caches are up */