From a5bca2152036de826595723437c5cbe8f6c13983 Mon Sep 17 00:00:00 2001 From: Tejun Heo Date: Thu, 3 Mar 2016 09:57:58 -0500 Subject: [PATCH] cgroup: factor out cgroup_create() out of cgroup_mkdir() 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 Acked-by: Zefan Li --- kernel/cgroup.c | 72 +++++++++++++++++++++++++++++-------------------- 1 file changed, 43 insertions(+), 29 deletions(-) diff --git a/kernel/cgroup.c b/kernel/cgroup.c index a6d484a667aa..e1b3d0fead05 100644 --- a/kernel/cgroup.c +++ b/kernel/cgroup.c @@ -4888,33 +4888,19 @@ err_free_css: 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) @@ -4978,6 +4964,40 @@ 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)) { @@ -5012,17 +5032,11 @@ 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; } /*