2014-10-15 05:39:25

by Rohit

Subject: [PATCH 1/1] Security : smack : Use kmem_cache for allocation and freeing of inode_smack

From: Rohit <[email protected]>

Use kmem_cache to allocate/free inode_smack since they are
alloced in high volumes making it a perfect case for kmem_cache.

Accounting of memory allocation is below :
total slack net count-alloc/free caller
Before (with kzalloc)
1919872 719952 1919872 29998/0 new_inode_smack+0x14
After (with kmem_cache)
1201680 0 1201680 30042/0 new_inode_smack+0x18

Signed-off-by: Rohit <[email protected]>
---
security/smack/smack_lsm.c | 13 ++++++++++---
1 file changed, 10 insertions(+), 3 deletions(-)

diff --git a/security/smack/smack_lsm.c b/security/smack/smack_lsm.c
index d515ec2..58a5c92 100644
--- a/security/smack/smack_lsm.c
+++ b/security/smack/smack_lsm.c
@@ -53,6 +53,7 @@
#define SMK_SENDING 2

LIST_HEAD(smk_ipv6_port_list);
+struct kmem_cache *smack_inode_cache;

#ifdef CONFIG_SECURITY_SMACK_BRINGUP
static void smk_bu_mode(int mode, char *s)
@@ -240,7 +241,7 @@ struct inode_smack *new_inode_smack(struct smack_known *skp)
{
struct inode_smack *isp;

- isp = kzalloc(sizeof(struct inode_smack), GFP_NOFS);
+ isp = kmem_cache_zalloc(smack_inode_cache, GFP_NOFS);
if (isp == NULL)
return NULL;

@@ -767,7 +768,7 @@ static int smack_inode_alloc_security(struct inode *inode)
*/
static void smack_inode_free_security(struct inode *inode)
{
- kfree(inode->i_security);
+ kmem_cache_free(smack_inode_cache, inode->i_security);
inode->i_security = NULL;
}

@@ -4264,10 +4265,16 @@ static __init int smack_init(void)
if (!security_module_enable(&smack_ops))
return 0;

+ smack_inode_cache = KMEM_CACHE(inode_smack, 0);
+ if (!smack_inode_cache)
+ return -ENOMEM;
+
tsp = new_task_smack(&smack_known_floor, &smack_known_floor,
GFP_KERNEL);
- if (tsp == NULL)
+ if (tsp == NULL) {
+ kmem_cache_destroy(smack_inode_cache);
return -ENOMEM;
+ }

printk(KERN_INFO "Smack: Initializing.\n");

--
1.7.9.5

2014-10-15 05:43:39

by Andrew Morton

Subject: Re: [PATCH 1/1] Security : smack : Use kmem_cache for allocation and freeing of inode_smack

On Wed, 15 Oct 2014 11:26:16 +0530 Rohit Kumar <[email protected]> wrote:

> From: Rohit <[email protected]>
>
> Use kmem_cache to allocate/free inode_smack since they are
> alloced in high volumes making it a perfect case for kmem_cache.
>
> Accounting of memory allocation is below :
> total slack net count-alloc/free caller
> Before (with kzalloc)
> 1919872 719952 1919872 29998/0 new_inode_smack+0x14
> After (with kmem_cache)
> 1201680 0 1201680 30042/0 new_inode_smack+0x18
>
> ...
>
> --- a/security/smack/smack_lsm.c
> +++ b/security/smack/smack_lsm.c
> @@ -53,6 +53,7 @@
> #define SMK_SENDING 2
>
> LIST_HEAD(smk_ipv6_port_list);
> +struct kmem_cache *smack_inode_cache;

static.