selinux: Use kmem_cache for hashtab_node

During random test as own device to check slub account,
we found some slack memory from hashtab_node(kmalloc-64).
By using kzalloc(), middle of test result like below:
allocated size 240768
request size 45144
slack size 195624
allocation count 3762

So, we want to use kmem_cache_zalloc() and that
can reduce memory size 52byte(slack size/alloc count) per each struct.

Signed-off-by: Kyeongdon Kim <kyeongdon.kim@lge.com>
Signed-off-by: Paul Moore <paul@paul-moore.com>
This commit is contained in:
Kyeongdon Kim 2017-09-06 18:50:19 +09:00 committed by Paul Moore
parent 2bd6bf03f4
commit 7c620ece12
3 changed files with 23 additions and 2 deletions

View File

@ -9,6 +9,8 @@
#include <linux/sched.h>
#include "hashtab.h"
static struct kmem_cache *hashtab_node_cachep;
struct hashtab *hashtab_create(u32 (*hash_value)(struct hashtab *h, const void *key),
int (*keycmp)(struct hashtab *h, const void *key1, const void *key2),
u32 size)
@ -57,7 +59,7 @@ int hashtab_insert(struct hashtab *h, void *key, void *datum)
if (cur && (h->keycmp(h, key, cur->key) == 0))
return -EEXIST;
newnode = kzalloc(sizeof(*newnode), GFP_KERNEL);
newnode = kmem_cache_zalloc(hashtab_node_cachep, GFP_KERNEL);
if (!newnode)
return -ENOMEM;
newnode->key = key;
@ -106,7 +108,7 @@ void hashtab_destroy(struct hashtab *h)
while (cur) {
temp = cur;
cur = cur->next;
kfree(temp);
kmem_cache_free(hashtab_node_cachep, temp);
}
h->htable[i] = NULL;
}
@ -166,3 +168,14 @@ void hashtab_stat(struct hashtab *h, struct hashtab_info *info)
info->slots_used = slots_used;
info->max_chain_len = max_chain_len;
}
void hashtab_cache_init(void)
{
hashtab_node_cachep = kmem_cache_create("hashtab_node",
sizeof(struct hashtab_node),
0, SLAB_PANIC, NULL);
}
void hashtab_cache_destroy(void)
{
kmem_cache_destroy(hashtab_node_cachep);
}

View File

@ -84,4 +84,8 @@ int hashtab_map(struct hashtab *h,
/* Fill info with some hash table statistics */
void hashtab_stat(struct hashtab *h, struct hashtab_info *info);
/* Use kmem_cache for hashtab_node */
void hashtab_cache_init(void);
void hashtab_cache_destroy(void);
#endif /* _SS_HASHTAB_H */

View File

@ -2060,10 +2060,12 @@ int security_load_policy(void *data, size_t len)
if (!ss_initialized) {
avtab_cache_init();
ebitmap_cache_init();
hashtab_cache_init();
rc = policydb_read(&policydb, fp);
if (rc) {
avtab_cache_destroy();
ebitmap_cache_destroy();
hashtab_cache_destroy();
goto out;
}
@ -2075,6 +2077,7 @@ int security_load_policy(void *data, size_t len)
policydb_destroy(&policydb);
avtab_cache_destroy();
ebitmap_cache_destroy();
hashtab_cache_destroy();
goto out;
}
@ -2083,6 +2086,7 @@ int security_load_policy(void *data, size_t len)
policydb_destroy(&policydb);
avtab_cache_destroy();
ebitmap_cache_destroy();
hashtab_cache_destroy();
goto out;
}