mm/slab_common: support the slub_debug boot option on specific object size

The slub_debug=PU,kmalloc-xx cannot work because in the
create_kmalloc_caches() the s->name is created after the
create_kmalloc_cache() is called.  The name is NULL in the
create_kmalloc_cache() so the kmem_cache_flags() would not set the
slub_debug flags to the s->flags.  The fix here set up a kmalloc_names
string array for the initialization purpose and delete the dynamic name
creation of kmalloc_caches.

[akpm@linux-foundation.org: s/kmalloc_names/kmalloc_info/, tweak comment text]
Signed-off-by: Gavin Guo <gavin.guo@canonical.com>
Acked-by: Christoph Lameter <cl@linux.com>
Cc: Pekka Enberg <penberg@kernel.org>
Cc: David Rientjes <rientjes@google.com>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

1 files changed, 22 insertions, 0 deletions

diff --git a/include/linux/slab.h b/include/linux/slab.h
index ffd24c830151..96f0ea506b5c 100644
--- a/include/linux/slab.h
+++ b/include/linux/slab.h
@@ -153,8 +153,30 @@ size_t ksize(const void *);
 #define ARCH_KMALLOC_MINALIGN ARCH_DMA_MINALIGN
 #define KMALLOC_MIN_SIZE ARCH_DMA_MINALIGN
 #define KMALLOC_SHIFT_LOW ilog2(ARCH_DMA_MINALIGN)
+/*
+ * The KMALLOC_LOOP_LOW is the definition for the for loop index start number
+ * to create the kmalloc_caches object in create_kmalloc_caches(). The first
+ * and the second are 96 and 192. You can see that in the kmalloc_index(), if
+ * the KMALLOC_MIN_SIZE <= 32, then return 1 (96). If KMALLOC_MIN_SIZE <= 64,
+ * then return 2 (192). If the KMALLOC_MIN_SIZE is bigger than 64, we don't
+ * need to initialize 96 and 192. Go directly to start the KMALLOC_SHIFT_LOW.
+ */
+#if KMALLOC_MIN_SIZE <= 32
+#define KMALLOC_LOOP_LOW 1
+#elif KMALLOC_MIN_SIZE <= 64
+#define KMALLOC_LOOP_LOW 2
+#else
+#define KMALLOC_LOOP_LOW KMALLOC_SHIFT_LOW
+#endif
+
 #else
 #define ARCH_KMALLOC_MINALIGN __alignof__(unsigned long long)
+/*
+ * The KMALLOC_MIN_SIZE of slub/slab/slob is 2^3/2^5/2^3. So, even slab is used.
+ * The KMALLOC_MIN_SIZE <= 32. The kmalloc-96 and kmalloc-192 should also be
+ * initialized.
+ */
+#define KMALLOC_LOOP_LOW 1
 #endif
 
 /*