mm/slub.c: wrap kmem_cache->cpu_partial in config CONFIG_SLUB_CPU_PARTIAL

kmem_cache->cpu_partial is just used when CONFIG_SLUB_CPU_PARTIAL is
set, so wrap it with config CONFIG_SLUB_CPU_PARTIAL will save some space
on 32bit arch.

This patch wraps kmem_cache->cpu_partial in config CONFIG_SLUB_CPU_PARTIAL
and wraps its sysfs too.

Link: http://lkml.kernel.org/r/20170502144533.10729-4-richard.weiyang@gmail.com
Signed-off-by: Wei Yang <richard.weiyang@gmail.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>
This commit is contained in:
Wei Yang 2017-07-06 15:36:34 -07:00 committed by Linus Torvalds
parent a93cf07bc3
commit e6d0e1dcf5
2 changed files with 51 additions and 31 deletions

View File

@ -86,7 +86,9 @@ struct kmem_cache {
int size; /* The size of an object including meta data */
int object_size; /* The size of an object without meta data */
int offset; /* Free pointer offset. */
#ifdef CONFIG_SLUB_CPU_PARTIAL
int cpu_partial; /* Number of per cpu partial objects to keep around */
#endif
struct kmem_cache_order_objects oo;
/* Allocation and freeing of slabs */
@ -131,6 +133,17 @@ struct kmem_cache {
struct kmem_cache_node *node[MAX_NUMNODES];
};
#ifdef CONFIG_SLUB_CPU_PARTIAL
#define slub_cpu_partial(s) ((s)->cpu_partial)
#define slub_set_cpu_partial(s, n) \
({ \
slub_cpu_partial(s) = (n); \
})
#else
#define slub_cpu_partial(s) (0)
#define slub_set_cpu_partial(s, n)
#endif // CONFIG_SLUB_CPU_PARTIAL
#ifdef CONFIG_SYSFS
#define SLAB_SUPPORTS_SYSFS
void sysfs_slab_release(struct kmem_cache *);

View File

@ -1829,7 +1829,7 @@ static void *get_partial_node(struct kmem_cache *s, struct kmem_cache_node *n,
stat(s, CPU_PARTIAL_NODE);
}
if (!kmem_cache_has_cpu_partial(s)
|| available > s->cpu_partial / 2)
|| available > slub_cpu_partial(s) / 2)
break;
}
@ -3404,6 +3404,39 @@ static void set_min_partial(struct kmem_cache *s, unsigned long min)
s->min_partial = min;
}
static void set_cpu_partial(struct kmem_cache *s)
{
#ifdef CONFIG_SLUB_CPU_PARTIAL
/*
* cpu_partial determined the maximum number of objects kept in the
* per cpu partial lists of a processor.
*
* Per cpu partial lists mainly contain slabs that just have one
* object freed. If they are used for allocation then they can be
* filled up again with minimal effort. The slab will never hit the
* per node partial lists and therefore no locking will be required.
*
* This setting also determines
*
* A) The number of objects from per cpu partial slabs dumped to the
* per node list when we reach the limit.
* B) The number of objects in cpu partial slabs to extract from the
* per node list when we run out of per cpu objects. We only fetch
* 50% to keep some capacity around for frees.
*/
if (!kmem_cache_has_cpu_partial(s))
s->cpu_partial = 0;
else if (s->size >= PAGE_SIZE)
s->cpu_partial = 2;
else if (s->size >= 1024)
s->cpu_partial = 6;
else if (s->size >= 256)
s->cpu_partial = 13;
else
s->cpu_partial = 30;
#endif
}
/*
* calculate_sizes() determines the order and the distribution of data within
* a slab object.
@ -3562,33 +3595,7 @@ static int kmem_cache_open(struct kmem_cache *s, unsigned long flags)
*/
set_min_partial(s, ilog2(s->size) / 2);
/*
* cpu_partial determined the maximum number of objects kept in the
* per cpu partial lists of a processor.
*
* Per cpu partial lists mainly contain slabs that just have one
* object freed. If they are used for allocation then they can be
* filled up again with minimal effort. The slab will never hit the
* per node partial lists and therefore no locking will be required.
*
* This setting also determines
*
* A) The number of objects from per cpu partial slabs dumped to the
* per node list when we reach the limit.
* B) The number of objects in cpu partial slabs to extract from the
* per node list when we run out of per cpu objects. We only fetch
* 50% to keep some capacity around for frees.
*/
if (!kmem_cache_has_cpu_partial(s))
s->cpu_partial = 0;
else if (s->size >= PAGE_SIZE)
s->cpu_partial = 2;
else if (s->size >= 1024)
s->cpu_partial = 6;
else if (s->size >= 256)
s->cpu_partial = 13;
else
s->cpu_partial = 30;
set_cpu_partial(s);
#ifdef CONFIG_NUMA
s->remote_node_defrag_ratio = 1000;
@ -3975,7 +3982,7 @@ void __kmemcg_cache_deactivate(struct kmem_cache *s)
* Disable empty slabs caching. Used to avoid pinning offline
* memory cgroups by kmem pages that can be freed.
*/
s->cpu_partial = 0;
slub_set_cpu_partial(s, 0);
s->min_partial = 0;
/*
@ -4915,7 +4922,7 @@ SLAB_ATTR(min_partial);
static ssize_t cpu_partial_show(struct kmem_cache *s, char *buf)
{
return sprintf(buf, "%u\n", s->cpu_partial);
return sprintf(buf, "%u\n", slub_cpu_partial(s));
}
static ssize_t cpu_partial_store(struct kmem_cache *s, const char *buf,
@ -4930,7 +4937,7 @@ static ssize_t cpu_partial_store(struct kmem_cache *s, const char *buf,
if (objects && !kmem_cache_has_cpu_partial(s))
return -EINVAL;
s->cpu_partial = objects;
slub_set_cpu_partial(s, objects);
flush_all(s);
return length;
}