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From f85163c82300f68eb73002d1b0e1a92288ff41fe Mon Sep 17 00:00:00 2001
From: Rohit <rohit.kr@samsung.com>
Date: Wed, 15 Oct 2014 17:40:41 +0530
Subject: [PATCH 43/54] Security: smack: replace kzalloc with kmem_cache for
inode_smack
The patch use kmem_cache to allocate/free inode_smack since they are
alloced in high volumes making it a perfect case for kmem_cache.
As per analysis, 24 bytes of memory is wasted per allocation due
to internal fragmentation. With kmem_cache, this can be avoided.
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
>From above data, we found that 719952 bytes(~700 KB) of memory is
saved on allocation of 29998 smack inodes.
Signed-off-by: Rohit <rohit.kr@samsung.com>
---
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 2f62a68..b3978ea 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);
+static 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;
}
@@ -4266,10 +4267,16 @@ 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");
--
2.1.4
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