Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1030400AbWCUOSL (ORCPT ); Tue, 21 Mar 2006 09:18:11 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1030402AbWCUOSK (ORCPT ); Tue, 21 Mar 2006 09:18:10 -0500 Received: from mail7.sea5.speakeasy.net ([69.17.117.9]:37085 "EHLO mail7.sea5.speakeasy.net") by vger.kernel.org with ESMTP id S1030400AbWCUOSJ (ORCPT ); Tue, 21 Mar 2006 09:18:09 -0500 Date: Tue, 21 Mar 2006 09:18:06 -0500 (EST) From: James Morris X-X-Sender: jmorris@excalibur.intercode To: Andrew Morton cc: linux-kernel@vger.kernel.org, Stephen Smalley Subject: [PATCH] SELinux - add slab cache for inode security struct Message-ID: MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2559 Lines: 71 This patch adds a slab cache for the SELinux inode security struct, one of which is allocated for every inode instantiated by the system. The memory savings are considerable. On 64-bit, instead of the size-128 cache, we have a slab object of 96 bytes, saving 32 bytes per object. After booting, I see about 4000 of these and then about 17,000 after a kernel compile. With this patch, we save around 530KB of kernel memory in the latter case. On 32-bit, the savings are about half of this. Please apply. Signed-off-by: James Morris Acked-by: Stephen Smalley --- security/selinux/hooks.c | 10 ++++++++-- 1 files changed, 8 insertions(+), 2 deletions(-) diff -purN -X dontdiff linux-2.6.16/security/selinux/hooks.c linux-2.6.16.w/security/selinux/hooks.c --- linux-2.6.16/security/selinux/hooks.c 2006-03-20 00:53:29.000000000 -0500 +++ linux-2.6.16.w/security/selinux/hooks.c 2006-03-20 20:14:19.000000000 -0500 @@ -117,6 +117,8 @@ static struct security_operations *secon static LIST_HEAD(superblock_security_head); static DEFINE_SPINLOCK(sb_security_lock); +static kmem_cache_t *sel_inode_cache; + /* Allocate and free functions for each kind of security blob. */ static int task_alloc_security(struct task_struct *task) @@ -146,10 +148,11 @@ static int inode_alloc_security(struct i struct task_security_struct *tsec = current->security; struct inode_security_struct *isec; - isec = kzalloc(sizeof(struct inode_security_struct), GFP_KERNEL); + isec = kmem_cache_alloc(sel_inode_cache, SLAB_KERNEL); if (!isec) return -ENOMEM; + memset(isec, 0, sizeof(*isec)); init_MUTEX(&isec->sem); INIT_LIST_HEAD(&isec->list); isec->inode = inode; @@ -172,7 +175,7 @@ static void inode_free_security(struct i spin_unlock(&sbsec->isec_lock); inode->i_security = NULL; - kfree(isec); + kmem_cache_free(sel_inode_cache, isec); } static int file_alloc_security(struct file *file) @@ -4376,6 +4379,9 @@ static __init int selinux_init(void) tsec = current->security; tsec->osid = tsec->sid = SECINITSID_KERNEL; + sel_inode_cache = kmem_cache_create("selinux_inode_security", + sizeof(struct inode_security_struct), + 0, SLAB_PANIC, NULL, NULL); avc_init(); original_ops = secondary_ops = security_ops; - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/