The operation order of cgroup creation is about to change and
cgroup_create_dir() is more of a hindrance than a proper abstraction.
Open-code it by moving the parent nlink adjustment next to self nlink
adjustment in cgroup_create_file() and the rest to cgroup_create().
This patch doesn't introduce any behavior change.
Signed-off-by: Tejun Heo <t...@kernel.org>
---
kernel/cgroup.c | 30 +++++-------------------------
1 file changed, 5 insertions(+), 25 deletions(-)
diff --git a/kernel/cgroup.c b/kernel/cgroup.c
index ed0e177..b042673 100644
--- a/kernel/cgroup.c
+++ b/kernel/cgroup.c
@@ -2652,6 +2652,7 @@ static int cgroup_create_file(struct dentry *dentry,
umode_t mode,
/* start off with i_nlink == 2 (for "." entry) */
inc_nlink(inode);
+ inc_nlink(dentry->d_parent->d_inode);
/* start with the directory inode held, so that we can
* populate it without racing with another mkdir */
@@ -2666,30 +2667,6 @@ static int cgroup_create_file(struct dentry *dentry,
umode_t mode,
return 0;
}
-/*
- * cgroup_create_dir - create a directory for an object.
- * @cgrp: the cgroup we create the directory for. It must have a valid
- * ->parent field. And we are going to fill its ->dentry field.
- * @dentry: dentry of the new cgroup
- * @mode: mode to set on new directory.
- */
-static int cgroup_create_dir(struct cgroup *cgrp, struct dentry *dentry,
- umode_t mode)
-{
- struct dentry *parent;
- int error = 0;
-
- parent = cgrp->parent->dentry;
- error = cgroup_create_file(dentry, S_IFDIR | mode, cgrp->root->sb);
- if (!error) {
- dentry->d_fsdata = cgrp;
- inc_nlink(parent->d_inode);
- rcu_assign_pointer(cgrp->dentry, dentry);
- }
-
- return error;
-}
-
/**
* cgroup_file_mode - deduce file mode of a control file
* @cft: the control file in question
@@ -4138,10 +4115,13 @@ static long cgroup_create(struct cgroup *parent, struct
dentry *dentry,
list_add_tail_rcu(&cgrp->sibling, &cgrp->parent->children);
root->number_of_cgroups++;
- err = cgroup_create_dir(cgrp, dentry, mode);
+ err = cgroup_create_file(dentry, S_IFDIR | mode, sb);
if (err < 0)
goto err_remove;
+ dentry->d_fsdata = cgrp;
+ rcu_assign_pointer(cgrp->dentry, dentry);
+
for_each_subsys(root, ss) {
/* each css holds a ref to the cgroup's dentry */
dget(dentry);
--
1.7.11.7
--
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