selinux: Use kmem_cache for hashtab_node
diff mbox

Message ID 1504691419-26972-1-git-send-email-kyeongdon.kim@lge.com
State New
Headers show

Commit Message

Kyeongdon Kim Sept. 6, 2017, 9:50 a.m. UTC
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>
---
 security/selinux/ss/hashtab.c  | 17 +++++++++++++++--
 security/selinux/ss/hashtab.h  |  4 ++++
 security/selinux/ss/services.c |  4 ++++
 3 files changed, 23 insertions(+), 2 deletions(-)

Comments

Paul Moore Sept. 7, 2017, 11:18 p.m. UTC | #1
On Wed, Sep 6, 2017 at 5:50 AM, Kyeongdon Kim <kyeongdon.kim@lge.com> wrote:
> 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>
> ---
>  security/selinux/ss/hashtab.c  | 17 +++++++++++++++--
>  security/selinux/ss/hashtab.h  |  4 ++++
>  security/selinux/ss/services.c |  4 ++++
>  3 files changed, 23 insertions(+), 2 deletions(-)

This seems reasonale, but I'm going to refrain from merging this until
after the merge window closes.

> diff --git a/security/selinux/ss/hashtab.c b/security/selinux/ss/hashtab.c
> index 686c391..bef7577 100644
> --- a/security/selinux/ss/hashtab.c
> +++ b/security/selinux/ss/hashtab.c
> @@ -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);
> +}
> diff --git a/security/selinux/ss/hashtab.h b/security/selinux/ss/hashtab.h
> index 009fb5e..d6883d3 100644
> --- a/security/selinux/ss/hashtab.h
> +++ b/security/selinux/ss/hashtab.h
> @@ -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 */
> diff --git a/security/selinux/ss/services.c b/security/selinux/ss/services.c
> index e4a1c0d..33cfe5d 100644
> --- a/security/selinux/ss/services.c
> +++ b/security/selinux/ss/services.c
> @@ -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;
>                 }
>
> --
> 2.6.2
>
Paul Moore Sept. 20, 2017, 4:09 p.m. UTC | #2
On Thu, Sep 7, 2017 at 7:18 PM, Paul Moore <paul@paul-moore.com> wrote:
> On Wed, Sep 6, 2017 at 5:50 AM, Kyeongdon Kim <kyeongdon.kim@lge.com> wrote:
>> 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>
>> ---
>>  security/selinux/ss/hashtab.c  | 17 +++++++++++++++--
>>  security/selinux/ss/hashtab.h  |  4 ++++
>>  security/selinux/ss/services.c |  4 ++++
>>  3 files changed, 23 insertions(+), 2 deletions(-)
>
> This seems reasonale, but I'm going to refrain from merging this until
> after the merge window closes.

I just merged this into selinux/next, thanks for your patience.

Patch
diff mbox

diff --git a/security/selinux/ss/hashtab.c b/security/selinux/ss/hashtab.c
index 686c391..bef7577 100644
--- a/security/selinux/ss/hashtab.c
+++ b/security/selinux/ss/hashtab.c
@@ -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);
+}
diff --git a/security/selinux/ss/hashtab.h b/security/selinux/ss/hashtab.h
index 009fb5e..d6883d3 100644
--- a/security/selinux/ss/hashtab.h
+++ b/security/selinux/ss/hashtab.h
@@ -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 */
diff --git a/security/selinux/ss/services.c b/security/selinux/ss/services.c
index e4a1c0d..33cfe5d 100644
--- a/security/selinux/ss/services.c
+++ b/security/selinux/ss/services.c
@@ -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;
 		}