From mboxrd@z Thu Jan 1 00:00:00 1970 From: Tejun Heo Subject: [PATCH 04/16] cgroup: factor out cgroup_create() out of cgroup_mkdir() Date: Wed, 24 Feb 2016 17:02:36 -0500 Message-ID: <1456351368-786-5-git-send-email-tj@kernel.org> References: <1456351368-786-1-git-send-email-tj@kernel.org> Return-path: DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20120113; h=sender:from:to:cc:subject:date:message-id:in-reply-to:references; bh=sXPhMgZC/2b5JBmGyTQJ5pQhqLePICdy1tZLsHR2WXg=; b=cQU/VfTZaUCKIp0ujzLmBnGrJK5gnFYO5yncRpVHXW26KXggyIxWSbU4HO1Rzm6/51 9ag3cmtEgCa3gyecY3sEp+U6FMifMIcI6Bfrk5OVNSunskDgxu8IEGe7gTTUIsWFdDAH AN7CRzuNEBmHAf3S4r+O/R3RciWzzDV1GfPXZ3JxulWL8vZu9+BTXAYRUklAIJyZJRBr jWvalJRWIpxKtziJ6ctr/796T4uPPOQcHPRoXoEAd3DCIB3h+cA9MIEgCdpg+fOu3zgj CIIKoQukabvoCmDF4jesy+JHWDJpxOPj0vjwaIue7Tkt4sWAg4dNUuhvUAWreGi67t9d kLeQ== In-Reply-To: <1456351368-786-1-git-send-email-tj@kernel.org> Sender: linux-kernel-owner@vger.kernel.org List-ID: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: lizefan@huawei.com, hannes@cmpxchg.org Cc: cgroups@vger.kernel.org, linux-kernel@vger.kernel.org, kernel-team@fb.com, Tejun Heo We're in the process of refactoring cgroup and css management paths to separate them out to eventually allow cgroups which aren't visible through cgroup fs. This patch factors out cgroup_create() out of cgroup_mkdir(). cgroup_create() contains all internal object creation and initialization. cgroup_mkdir() uses cgroup_create() to create the internal cgroup and adds interface directory and file creation. This patch doesn't cause any behavior differences. Signed-off-by: Tejun Heo --- kernel/cgroup.c | 72 ++++++++++++++++++++++++++++++++++----------------------- 1 file changed, 43 insertions(+), 29 deletions(-) diff --git a/kernel/cgroup.c b/kernel/cgroup.c index 204f78a..070c078 100644 --- a/kernel/cgroup.c +++ b/kernel/cgroup.c @@ -4884,33 +4884,19 @@ static struct cgroup_subsys_state *css_create(struct cgroup *cgrp, return ERR_PTR(err); } -static int cgroup_mkdir(struct kernfs_node *parent_kn, const char *name, - umode_t mode) +static struct cgroup *cgroup_create(struct cgroup *parent) { - struct cgroup *parent, *cgrp, *tcgrp; - struct cgroup_root *root; + struct cgroup_root *root = parent->root; struct cgroup_subsys *ss; - struct kernfs_node *kn; - int level, ssid, ret; - - /* Do not accept '\n' to prevent making /proc//cgroup unparsable. - */ - if (strchr(name, '\n')) - return -EINVAL; - - parent = cgroup_kn_lock_live(parent_kn); - if (!parent) - return -ENODEV; - root = parent->root; - level = parent->level + 1; + struct cgroup *cgrp, *tcgrp; + int level = parent->level + 1; + int ssid, ret; /* allocate the cgroup and its ID, 0 is reserved for the root */ cgrp = kzalloc(sizeof(*cgrp) + sizeof(cgrp->ancestor_ids[0]) * (level + 1), GFP_KERNEL); - if (!cgrp) { - ret = -ENOMEM; - goto out_unlock; - } + if (!cgrp) + return ERR_PTR(-ENOMEM); ret = percpu_ref_init(&cgrp->self.refcnt, css_release, 0, GFP_KERNEL); if (ret) @@ -4974,6 +4960,40 @@ static int cgroup_mkdir(struct kernfs_node *parent_kn, const char *name, cgroup_refresh_subtree_ss_mask(cgrp); } + return cgrp; + +out_cancel_ref: + percpu_ref_exit(&cgrp->self.refcnt); +out_free_cgrp: + kfree(cgrp); + return ERR_PTR(ret); +out_destroy: + cgroup_destroy_locked(cgrp); + return ERR_PTR(ret); +} + +static int cgroup_mkdir(struct kernfs_node *parent_kn, const char *name, + umode_t mode) +{ + struct cgroup *parent, *cgrp; + struct cgroup_subsys *ss; + struct kernfs_node *kn; + int ssid, ret; + + /* do not accept '\n' to prevent making /proc//cgroup unparsable */ + if (strchr(name, '\n')) + return -EINVAL; + + parent = cgroup_kn_lock_live(parent_kn); + if (!parent) + return -ENODEV; + + cgrp = cgroup_create(parent); + if (IS_ERR(cgrp)) { + ret = PTR_ERR(cgrp); + goto out_unlock; + } + /* create the directory */ kn = kernfs_create_dir(parent->kn, name, mode, cgrp); if (IS_ERR(kn)) { @@ -5008,17 +5028,11 @@ static int cgroup_mkdir(struct kernfs_node *parent_kn, const char *name, ret = 0; goto out_unlock; -out_cancel_ref: - percpu_ref_exit(&cgrp->self.refcnt); -out_free_cgrp: - kfree(cgrp); +out_destroy: + cgroup_destroy_locked(cgrp); out_unlock: cgroup_kn_unlock(parent_kn); return ret; - -out_destroy: - cgroup_destroy_locked(cgrp); - goto out_unlock; } /* -- 2.5.0