Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754536AbZCLBsX (ORCPT ); Wed, 11 Mar 2009 21:48:23 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1754456AbZCLBrg (ORCPT ); Wed, 11 Mar 2009 21:47:36 -0400 Received: from cn.fujitsu.com ([222.73.24.84]:50184 "EHLO song.cn.fujitsu.com" rhost-flags-OK-FAIL-OK-OK) by vger.kernel.org with ESMTP id S1753356AbZCLBrc (ORCPT ); Wed, 11 Mar 2009 21:47:32 -0400 Message-ID: <49B869BB.7030907@cn.fujitsu.com> Date: Thu, 12 Mar 2009 09:47:39 +0800 From: Li Zefan User-Agent: Thunderbird 2.0.0.9 (X11/20071115) MIME-Version: 1.0 To: Andrew Morton CC: Paul Menage , "Serge E. Hallyn" , LKML , Linux Containers Subject: [PATCH] devcgroup: avoid using cgroup_lock Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 3138 Lines: 102 There is nothing special that has to be protected by cgroup_lock, so introduce devcgroup_mtuex for it's own use. Signed-off-by: Li Zefan --- security/device_cgroup.c | 21 +++++++++++++-------- 1 files changed, 13 insertions(+), 8 deletions(-) diff --git a/security/device_cgroup.c b/security/device_cgroup.c index 3aacd0f..5fda7df 100644 --- a/security/device_cgroup.c +++ b/security/device_cgroup.c @@ -11,6 +11,7 @@ #include #include #include +#include #define ACC_MKNOD 1 #define ACC_READ 2 @@ -21,9 +22,11 @@ #define DEV_CHAR 2 #define DEV_ALL 4 /* this represents all devices */ +static DEFINE_MUTEX(devcgroup_mutex); + /* * whitelist locking rules: - * hold cgroup_lock() for update/read. + * hold devcgroup_mutex for update/read. * hold rcu_read_lock() for read. */ @@ -67,7 +70,7 @@ static int devcgroup_can_attach(struct cgroup_subsys *ss, } /* - * called under cgroup_lock() + * called under devcgroup_mutex */ static int dev_whitelist_copy(struct list_head *dest, struct list_head *orig) { @@ -92,7 +95,7 @@ free_and_exit: /* Stupid prototype - don't bother combining existing entries */ /* - * called under cgroup_lock() + * called under devcgroup_mutex */ static int dev_whitelist_add(struct dev_cgroup *dev_cgroup, struct dev_whitelist_item *wh) @@ -130,7 +133,7 @@ static void whitelist_item_free(struct rcu_head *rcu) } /* - * called under cgroup_lock() + * called under devcgroup_mutex */ static void dev_whitelist_rm(struct dev_cgroup *dev_cgroup, struct dev_whitelist_item *wh) @@ -185,8 +188,10 @@ static struct cgroup_subsys_state *devcgroup_create(struct cgroup_subsys *ss, list_add(&wh->list, &dev_cgroup->whitelist); } else { parent_dev_cgroup = cgroup_to_devcgroup(parent_cgroup); + mutex_lock(&devcgroup_mutex); ret = dev_whitelist_copy(&dev_cgroup->whitelist, &parent_dev_cgroup->whitelist); + mutex_unlock(&devcgroup_mutex); if (ret) { kfree(dev_cgroup); return ERR_PTR(ret); @@ -273,7 +278,7 @@ static int devcgroup_seq_read(struct cgroup *cgroup, struct cftype *cft, * does the access granted to dev_cgroup c contain the access * requested in whitelist item refwh. * return 1 if yes, 0 if no. - * call with c->lock held + * call with devcgroup_mutex held */ static int may_access_whitelist(struct dev_cgroup *c, struct dev_whitelist_item *refwh) @@ -426,11 +431,11 @@ static int devcgroup_access_write(struct cgroup *cgrp, struct cftype *cft, const char *buffer) { int retval; - if (!cgroup_lock_live_group(cgrp)) - return -ENODEV; + + mutex_lock(&devcgroup_mutex); retval = devcgroup_update_access(cgroup_to_devcgroup(cgrp), cft->private, buffer); - cgroup_unlock(); + mutex_unlock(&devcgroup_mutex); return retval; } -- 1.5.4.rc3 -- 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/