mm/slab_common.c: make calculate_alignment() static

calculate_alignment() function is only used inside slab_common.c.  So
make it static and let the compiler do more optimizations.

After this patch there's a small improvement in text and data size.

  $ gcc --version
    gcc (GCC) 7.2.1 20171128

Before:
  text	   data	    bss	    dec	     hex	filename
  9890457  3828702  1212364 14931523 e3d643	vmlinux

After:
  text	   data	    bss	    dec	     hex	filename
  9890437  3828670  1212364 14931471 e3d60f	vmlinux

Also I fixed a style problem reported by checkpatch.

  WARNING: Missing a blank line after declarations
  #53: FILE: mm/slab_common.c:286:
  +		unsigned long ralign = cache_line_size();
  +		while (size <= ralign / 2)

Link: http://lkml.kernel.org/r/20171210080132.406-1-bhlee.kernel@gmail.com
Signed-off-by: Byongho Lee <bhlee.kernel@gmail.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Cc: 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>

diff --git a/mm/slab.h b/mm/slab.h
index ad657ffa44e5db782c08ba53a71a6ccbc2089800..e8e2095a61853a62cffc646d8d45939c6efbd4b8 100644 (file)
--- a/mm/slab.h
+++ b/mm/slab.h
@@ -78,9 +78,6 @@ extern const struct kmalloc_info_struct {
        unsigned long size;
 } kmalloc_info[];
 
-unsigned long calculate_alignment(slab_flags_t flags,
-               unsigned long align, unsigned long size);
-
 #ifndef CONFIG_SLOB
 /* Kmalloc array related functions */
 void setup_kmalloc_cache_index_table(void);

diff --git a/mm/slab_common.c b/mm/slab_common.c
index c8cb36774ba1802c925c0b65609a15d7241d5aee..deeddf95cdcf158141bd942c86fe5f424a738d38 100644 (file)
--- a/mm/slab_common.c
+++ b/mm/slab_common.c
@@ -267,6 +267,35 @@ static inline void memcg_unlink_cache(struct kmem_cache *s)
 }
 #endif /* CONFIG_MEMCG && !CONFIG_SLOB */
 
+/*
+ * Figure out what the alignment of the objects will be given a set of
+ * flags, a user specified alignment and the size of the objects.
+ */
+static unsigned long calculate_alignment(unsigned long flags,
+               unsigned long align, unsigned long size)
+{
+       /*
+        * If the user wants hardware cache aligned objects then follow that
+        * suggestion if the object is sufficiently large.
+        *
+        * The hardware cache alignment cannot override the specified
+        * alignment though. If that is greater then use it.
+        */
+       if (flags & SLAB_HWCACHE_ALIGN) {
+               unsigned long ralign;
+
+               ralign = cache_line_size();
+               while (size <= ralign / 2)
+                       ralign /= 2;
+               align = max(align, ralign);
+       }
+
+       if (align < ARCH_SLAB_MINALIGN)
+               align = ARCH_SLAB_MINALIGN;
+
+       return ALIGN(align, sizeof(void *));
+}
+
 /*
  * Find a mergeable slab cache
  */
@@ -337,33 +366,6 @@ struct kmem_cache *find_mergeable(size_t size, size_t align,
        return NULL;
 }
 
-/*
- * Figure out what the alignment of the objects will be given a set of
- * flags, a user specified alignment and the size of the objects.
- */
-unsigned long calculate_alignment(slab_flags_t flags,
-               unsigned long align, unsigned long size)
-{
-       /*
-        * If the user wants hardware cache aligned objects then follow that
-        * suggestion if the object is sufficiently large.
-        *
-        * The hardware cache alignment cannot override the specified
-        * alignment though. If that is greater then use it.
-        */
-       if (flags & SLAB_HWCACHE_ALIGN) {
-               unsigned long ralign = cache_line_size();
-               while (size <= ralign / 2)
-                       ralign /= 2;
-               align = max(align, ralign);
-       }
-
-       if (align < ARCH_SLAB_MINALIGN)
-               align = ARCH_SLAB_MINALIGN;
-
-       return ALIGN(align, sizeof(void *));
-}
-
 static struct kmem_cache *create_cache(const char *name,
                size_t object_size, size_t size, size_t align,
                slab_flags_t flags, void (*ctor)(void *),