Commit a5bca215 authored by Tejun Heo's avatar Tejun Heo
Browse files

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: default avatarTejun Heo <tj@kernel.org>
Acked-by: default avatarZefan Li <lizefan@huawei.com>
parent 195e9b6c

kernel/cgroup.c

+43 −29
Original line number Diff line number Diff line
@@ -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/<pid>/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/<pid>/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;

}



/*

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