Commit 692ae74a authored by Byongho Lee's avatar Byongho Lee Committed by Linus Torvalds
Browse files

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: default avatarByongho Lee <bhlee.kernel@gmail.com>
Acked-by: default avatarMichal 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: default avatarAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
parent d984187e

mm/slab.h

+0 −3
Original line number Diff line number Diff line
@@ -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);

mm/slab_common.c

+29 −27
Original line number Diff line number Diff line
@@ -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 *),

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