slab: introduce alien_cache
Currently, we use array_cache for alien_cache. Although they are mostly similar, there is one difference, that is, need for spinlock. We don't need spinlock for array_cache itself, but to use array_cache for alien_cache, array_cache structure should have spinlock. This is needless overhead, so removing it would be better. This patch prepare it by introducing alien_cache and using it. In the following patch, we remove spinlock in array_cache. Signed-off-by: Joonsoo Kim <iamjoonsoo.kim@lge.com> Acked-by: Christoph Lameter <cl@linux.com> Cc: Pekka Enberg <penberg@kernel.org> Cc: David Rientjes <rientjes@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit is contained in:
Joonsoo Kim
Linus Torvalds
parent
1fe00d50a9
commit
c8522a3a58
106
mm/slab.c
106
mm/slab.c
@ -203,6 +203,11 @@ struct array_cache {
|
||||
*/
|
||||
};
|
||||
|
||||
struct alien_cache {
|
||||
spinlock_t lock;
|
||||
struct array_cache ac;
|
||||
};
|
||||
|
||||
#define SLAB_OBJ_PFMEMALLOC 1
|
||||
static inline bool is_obj_pfmemalloc(void *objp)
|
||||
{
|
||||
@ -491,7 +496,7 @@ static void slab_set_lock_classes(struct kmem_cache *cachep,
|
||||
struct lock_class_key *l3_key, struct lock_class_key *alc_key,
|
||||
struct kmem_cache_node *n)
|
||||
{
|
||||
struct array_cache **alc;
|
||||
struct alien_cache **alc;
|
||||
int r;
|
||||
|
||||
lockdep_set_class(&n->list_lock, l3_key);
|
||||
@ -507,7 +512,7 @@ static void slab_set_lock_classes(struct kmem_cache *cachep,
|
||||
return;
|
||||
for_each_node(r) {
|
||||
if (alc[r])
|
||||
lockdep_set_class(&alc[r]->lock, alc_key);
|
||||
lockdep_set_class(&(alc[r]->ac.lock), alc_key);
|
||||
}
|
||||
}
|
||||
|
||||
@ -965,12 +970,13 @@ static int transfer_objects(struct array_cache *to,
|
||||
#define drain_alien_cache(cachep, alien) do { } while (0)
|
||||
#define reap_alien(cachep, n) do { } while (0)
|
||||
|
||||
static inline struct array_cache **alloc_alien_cache(int node, int limit, gfp_t gfp)
|
||||
static inline struct alien_cache **alloc_alien_cache(int node,
|
||||
int limit, gfp_t gfp)
|
||||
{
|
||||
return (struct array_cache **)BAD_ALIEN_MAGIC;
|
||||
return (struct alien_cache **)BAD_ALIEN_MAGIC;
|
||||
}
|
||||
|
||||
static inline void free_alien_cache(struct array_cache **ac_ptr)
|
||||
static inline void free_alien_cache(struct alien_cache **ac_ptr)
|
||||
{
|
||||
}
|
||||
|
||||
@ -996,40 +1002,52 @@ static inline void *____cache_alloc_node(struct kmem_cache *cachep,
|
||||
static void *____cache_alloc_node(struct kmem_cache *, gfp_t, int);
|
||||
static void *alternate_node_alloc(struct kmem_cache *, gfp_t);
|
||||
|
||||
static struct array_cache **alloc_alien_cache(int node, int limit, gfp_t gfp)
|
||||
static struct alien_cache *__alloc_alien_cache(int node, int entries,
|
||||
int batch, gfp_t gfp)
|
||||
{
|
||||
struct array_cache **ac_ptr;
|
||||
int memsize = sizeof(void *) * entries + sizeof(struct alien_cache);
|
||||
struct alien_cache *alc = NULL;
|
||||
|
||||
alc = kmalloc_node(memsize, gfp, node);
|
||||
init_arraycache(&alc->ac, entries, batch);
|
||||
return alc;
|
||||
}
|
||||
|
||||
static struct alien_cache **alloc_alien_cache(int node, int limit, gfp_t gfp)
|
||||
{
|
||||
struct alien_cache **alc_ptr;
|
||||
int memsize = sizeof(void *) * nr_node_ids;
|
||||
int i;
|
||||
|
||||
if (limit > 1)
|
||||
limit = 12;
|
||||
ac_ptr = kzalloc_node(memsize, gfp, node);
|
||||
if (ac_ptr) {
|
||||
for_each_node(i) {
|
||||
if (i == node || !node_online(i))
|
||||
continue;
|
||||
ac_ptr[i] = alloc_arraycache(node, limit, 0xbaadf00d, gfp);
|
||||
if (!ac_ptr[i]) {
|
||||
for (i--; i >= 0; i--)
|
||||
kfree(ac_ptr[i]);
|
||||
kfree(ac_ptr);
|
||||
return NULL;
|
||||
}
|
||||
alc_ptr = kzalloc_node(memsize, gfp, node);
|
||||
if (!alc_ptr)
|
||||
return NULL;
|
||||
|
||||
for_each_node(i) {
|
||||
if (i == node || !node_online(i))
|
||||
continue;
|
||||
alc_ptr[i] = __alloc_alien_cache(node, limit, 0xbaadf00d, gfp);
|
||||
if (!alc_ptr[i]) {
|
||||
for (i--; i >= 0; i--)
|
||||
kfree(alc_ptr[i]);
|
||||
kfree(alc_ptr);
|
||||
return NULL;
|
||||
}
|
||||
}
|
||||
return ac_ptr;
|
||||
return alc_ptr;
|
||||
}
|
||||
|
||||
static void free_alien_cache(struct array_cache **ac_ptr)
|
||||
static void free_alien_cache(struct alien_cache **alc_ptr)
|
||||
{
|
||||
int i;
|
||||
|
||||
if (!ac_ptr)
|
||||
if (!alc_ptr)
|
||||
return;
|
||||
for_each_node(i)
|
||||
kfree(ac_ptr[i]);
|
||||
kfree(ac_ptr);
|
||||
kfree(alc_ptr[i]);
|
||||
kfree(alc_ptr);
|
||||
}
|
||||
|
||||
static void __drain_alien_cache(struct kmem_cache *cachep,
|
||||
@ -1063,25 +1081,31 @@ static void reap_alien(struct kmem_cache *cachep, struct kmem_cache_node *n)
|
||||
int node = __this_cpu_read(slab_reap_node);
|
||||
|
||||
if (n->alien) {
|
||||
struct array_cache *ac = n->alien[node];
|
||||
struct alien_cache *alc = n->alien[node];
|
||||
struct array_cache *ac;
|
||||
|
||||
if (ac && ac->avail && spin_trylock_irq(&ac->lock)) {
|
||||
__drain_alien_cache(cachep, ac, node);
|
||||
spin_unlock_irq(&ac->lock);
|
||||
if (alc) {
|
||||
ac = &alc->ac;
|
||||
if (ac->avail && spin_trylock_irq(&ac->lock)) {
|
||||
__drain_alien_cache(cachep, ac, node);
|
||||
spin_unlock_irq(&ac->lock);
|
||||
}
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
static void drain_alien_cache(struct kmem_cache *cachep,
|
||||
struct array_cache **alien)
|
||||
struct alien_cache **alien)
|
||||
{
|
||||
int i = 0;
|
||||
struct alien_cache *alc;
|
||||
struct array_cache *ac;
|
||||
unsigned long flags;
|
||||
|
||||
for_each_online_node(i) {
|
||||
ac = alien[i];
|
||||
if (ac) {
|
||||
alc = alien[i];
|
||||
if (alc) {
|
||||
ac = &alc->ac;
|
||||
spin_lock_irqsave(&ac->lock, flags);
|
||||
__drain_alien_cache(cachep, ac, i);
|
||||
spin_unlock_irqrestore(&ac->lock, flags);
|
||||
@ -1093,7 +1117,8 @@ static inline int cache_free_alien(struct kmem_cache *cachep, void *objp)
|
||||
{
|
||||
int nodeid = page_to_nid(virt_to_page(objp));
|
||||
struct kmem_cache_node *n;
|
||||
struct array_cache *alien = NULL;
|
||||
struct alien_cache *alien = NULL;
|
||||
struct array_cache *ac;
|
||||
int node;
|
||||
LIST_HEAD(list);
|
||||
|
||||
@ -1110,13 +1135,14 @@ static inline int cache_free_alien(struct kmem_cache *cachep, void *objp)
|
||||
STATS_INC_NODEFREES(cachep);
|
||||
if (n->alien && n->alien[nodeid]) {
|
||||
alien = n->alien[nodeid];
|
||||
spin_lock(&alien->lock);
|
||||
if (unlikely(alien->avail == alien->limit)) {
|
||||
ac = &alien->ac;
|
||||
spin_lock(&ac->lock);
|
||||
if (unlikely(ac->avail == ac->limit)) {
|
||||
STATS_INC_ACOVERFLOW(cachep);
|
||||
__drain_alien_cache(cachep, alien, nodeid);
|
||||
__drain_alien_cache(cachep, ac, nodeid);
|
||||
}
|
||||
ac_put_obj(cachep, alien, objp);
|
||||
spin_unlock(&alien->lock);
|
||||
ac_put_obj(cachep, ac, objp);
|
||||
spin_unlock(&ac->lock);
|
||||
} else {
|
||||
n = get_node(cachep, nodeid);
|
||||
spin_lock(&n->list_lock);
|
||||
@ -1191,7 +1217,7 @@ static void cpuup_canceled(long cpu)
|
||||
list_for_each_entry(cachep, &slab_caches, list) {
|
||||
struct array_cache *nc;
|
||||
struct array_cache *shared;
|
||||
struct array_cache **alien;
|
||||
struct alien_cache **alien;
|
||||
LIST_HEAD(list);
|
||||
|
||||
/* cpu is dead; no one can alloc from it. */
|
||||
@ -1272,7 +1298,7 @@ static int cpuup_prepare(long cpu)
|
||||
list_for_each_entry(cachep, &slab_caches, list) {
|
||||
struct array_cache *nc;
|
||||
struct array_cache *shared = NULL;
|
||||
struct array_cache **alien = NULL;
|
||||
struct alien_cache **alien = NULL;
|
||||
|
||||
nc = alloc_arraycache(node, cachep->limit,
|
||||
cachep->batchcount, GFP_KERNEL);
|
||||
@ -3762,7 +3788,7 @@ static int alloc_kmem_cache_node(struct kmem_cache *cachep, gfp_t gfp)
|
||||
int node;
|
||||
struct kmem_cache_node *n;
|
||||
struct array_cache *new_shared;
|
||||
struct array_cache **new_alien = NULL;
|
||||
struct alien_cache **new_alien = NULL;
|
||||
|
||||
for_each_online_node(node) {
|
||||
|
||||
|
||||
@ -276,7 +276,7 @@ struct kmem_cache_node {
|
||||
unsigned int free_limit;
|
||||
unsigned int colour_next; /* Per-node cache coloring */
|
||||
struct array_cache *shared; /* shared per node */
|
||||
struct array_cache **alien; /* on other nodes */
|
||||
struct alien_cache **alien; /* on other nodes */
|
||||
unsigned long next_reap; /* updated without locking */
|
||||
int free_touched; /* updated without locking */
|
||||
#endif
|
||||
|
||||
Loading…
Reference in New Issue
Block a user