Commit 8598351e authored by Vlastimil Babka's avatar Vlastimil Babka
Browse files

mm/slab: move and refactor __kmem_cache_alias() 



Move __kmem_cache_alias() to slab_common.c since it's called by
__kmem_cache_create_args() and calls find_mergeable() that both
are in this file. We can remove two slab.h declarations and make
them static. Instead declare sysfs_slab_alias() from slub.c so
that __kmem_cache_alias() can keep calling it.

Add args parameter to __kmem_cache_alias() and find_mergeable() instead
of align and ctor. With that we can also move the checks for usersize
and sheaf_capacity there from __kmem_cache_create_args() and make the
result more symmetric with slab_unmergeable().

No functional changes intended.

Reviewed-by: default avatarHarry Yoo <harry.yoo@oracle.com>
Reviewed-by: default avatarSuren Baghdasaryan <surenb@google.com>
Reviewed-by: default avatarLiam R. Howlett <Liam.Howlett@oracle.com>
Signed-off-by: default avatarVlastimil Babka <vbabka@suse.cz>
parent b26e52c5

mm/slab.h

+3 −5
Original line number Diff line number Diff line
@@ -281,9 +281,12 @@ struct kmem_cache { 
#define SLAB_SUPPORTS_SYSFS 1

void sysfs_slab_unlink(struct kmem_cache *s);

void sysfs_slab_release(struct kmem_cache *s);

int sysfs_slab_alias(struct kmem_cache *s, const char *name);

#else

static inline void sysfs_slab_unlink(struct kmem_cache *s) { }

static inline void sysfs_slab_release(struct kmem_cache *s) { }

static inline int sysfs_slab_alias(struct kmem_cache *s, const char *name)

							{ return 0; }

#endif



void *fixup_red_left(struct kmem_cache *s, void *p);
@@ -400,11 +403,6 @@ extern void create_boot_cache(struct kmem_cache *, const char *name, 
			unsigned int useroffset, unsigned int usersize);



int slab_unmergeable(struct kmem_cache *s);

struct kmem_cache *find_mergeable(unsigned size, unsigned align,

		slab_flags_t flags, const char *name, void (*ctor)(void *));

struct kmem_cache *

__kmem_cache_alias(const char *name, unsigned int size, unsigned int align,

		   slab_flags_t flags, void (*ctor)(void *));



slab_flags_t kmem_cache_flags(slab_flags_t flags, const char *name);

mm/slab_common.c

+37 −7
Original line number Diff line number Diff line
@@ -174,15 +174,22 @@ int slab_unmergeable(struct kmem_cache *s) 
	return 0;

}



struct kmem_cache *find_mergeable(unsigned int size, unsigned int align,

		slab_flags_t flags, const char *name, void (*ctor)(void *))

static struct kmem_cache *find_mergeable(unsigned int size, slab_flags_t flags,

		const char *name, struct kmem_cache_args *args)

{

	struct kmem_cache *s;

	unsigned int align;



	if (slab_nomerge)

		return NULL;



	if (ctor)

	if (args->ctor)

		return NULL;



	if (IS_ENABLED(CONFIG_HARDENED_USERCOPY) && args->usersize)

		return NULL;



	if (args->sheaf_capacity)

		return NULL;



	flags = kmem_cache_flags(flags, name);
@@ -191,7 +198,7 @@ struct kmem_cache *find_mergeable(unsigned int size, unsigned int align, 
		return NULL;



	size = ALIGN(size, sizeof(void *));

	align = calculate_alignment(flags, align, size);

	align = calculate_alignment(flags, args->align, size);

	size = ALIGN(size, align);



	list_for_each_entry_reverse(s, &slab_caches, list) {
@@ -252,6 +259,31 @@ static struct kmem_cache *create_cache(const char *name, 
	return ERR_PTR(err);

}



static struct kmem_cache *

__kmem_cache_alias(const char *name, unsigned int size, slab_flags_t flags,

		   struct kmem_cache_args *args)

{

	struct kmem_cache *s;



	s = find_mergeable(size, flags, name, args);

	if (s) {

		if (sysfs_slab_alias(s, name))

			pr_err("SLUB: Unable to add cache alias %s to sysfs\n",

			       name);



		s->refcount++;



		/*

		 * Adjust the object sizes so that we clear

		 * the complete object on kzalloc.

		 */

		s->object_size = max(s->object_size, size);

		s->inuse = max(s->inuse, ALIGN(size, sizeof(void *)));

	}



	return s;

}



/**

 * __kmem_cache_create_args - Create a kmem cache.

 * @name: A string which is used in /proc/slabinfo to identify this cache.
@@ -323,9 +355,7 @@ struct kmem_cache *__kmem_cache_create_args(const char *name, 
		    object_size - args->usersize < args->useroffset))

		args->usersize = args->useroffset = 0;



	if (!args->usersize && !args->sheaf_capacity)

		s = __kmem_cache_alias(name, object_size, args->align, flags,

				       args->ctor);

	s = __kmem_cache_alias(name, object_size, flags, args);

	if (s)

		goto out_unlock;

mm/slub.c

+1 −29
Original line number Diff line number Diff line
@@ -350,11 +350,8 @@ enum track_item { TRACK_ALLOC, TRACK_FREE }; 


#ifdef SLAB_SUPPORTS_SYSFS

static int sysfs_slab_add(struct kmem_cache *);

static int sysfs_slab_alias(struct kmem_cache *, const char *);

#else

static inline int sysfs_slab_add(struct kmem_cache *s) { return 0; }

static inline int sysfs_slab_alias(struct kmem_cache *s, const char *p)

							{ return 0; }

#endif



#if defined(CONFIG_DEBUG_FS) && defined(CONFIG_SLUB_DEBUG)
@@ -8580,31 +8577,6 @@ void __init kmem_cache_init_late(void) 
	WARN_ON(!flushwq);

}



struct kmem_cache *

__kmem_cache_alias(const char *name, unsigned int size, unsigned int align,

		   slab_flags_t flags, void (*ctor)(void *))

{

	struct kmem_cache *s;



	s = find_mergeable(size, align, flags, name, ctor);

	if (s) {

		if (sysfs_slab_alias(s, name))

			pr_err("SLUB: Unable to add cache alias %s to sysfs\n",

			       name);



		s->refcount++;



		/*

		 * Adjust the object sizes so that we clear

		 * the complete object on kzalloc.

		 */

		s->object_size = max(s->object_size, size);

		s->inuse = max(s->inuse, ALIGN(size, sizeof(void *)));

	}



	return s;

}



int do_kmem_cache_create(struct kmem_cache *s, const char *name,

			 unsigned int size, struct kmem_cache_args *args,

			 slab_flags_t flags)
@@ -9837,7 +9809,7 @@ struct saved_alias { 


static struct saved_alias *alias_list;



static int sysfs_slab_alias(struct kmem_cache *s, const char *name)

int sysfs_slab_alias(struct kmem_cache *s, const char *name)

{

	struct saved_alias *al;