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Diffstat (limited to 'kernel/cgroup.c')
-rw-r--r--kernel/cgroup.c36
1 files changed, 18 insertions, 18 deletions
diff --git a/kernel/cgroup.c b/kernel/cgroup.c
index 72fcd3069a9..b303dfc7dce 100644
--- a/kernel/cgroup.c
+++ b/kernel/cgroup.c
@@ -255,12 +255,17 @@ int cgroup_lock_is_held(void)
EXPORT_SYMBOL_GPL(cgroup_lock_is_held);
+static int css_unbias_refcnt(int refcnt)
+{
+ return refcnt >= 0 ? refcnt : refcnt - CSS_DEACT_BIAS;
+}
+
/* the current nr of refs, always >= 0 whether @css is deactivated or not */
static int css_refcnt(struct cgroup_subsys_state *css)
{
int v = atomic_read(&css->refcnt);
- return v >= 0 ? v : v - CSS_DEACT_BIAS;
+ return css_unbias_refcnt(v);
}
/* convenient tests for these bits */
@@ -896,13 +901,10 @@ static void cgroup_diput(struct dentry *dentry, struct inode *inode)
mutex_unlock(&cgroup_mutex);
/*
- * We want to drop the active superblock reference from the
- * cgroup creation after all the dentry refs are gone -
- * kill_sb gets mighty unhappy otherwise. Mark
- * dentry->d_fsdata with cgroup_diput() to tell
- * cgroup_d_release() to call deactivate_super().
+ * Drop the active superblock reference that we took when we
+ * created the cgroup
*/
- dentry->d_fsdata = cgroup_diput;
+ deactivate_super(cgrp->root->sb);
/*
* if we're getting rid of the cgroup, refcount should ensure
@@ -928,13 +930,6 @@ static int cgroup_delete(const struct dentry *d)
return 1;
}
-static void cgroup_d_release(struct dentry *dentry)
-{
- /* did cgroup_diput() tell me to deactivate super? */
- if (dentry->d_fsdata == cgroup_diput)
- deactivate_super(dentry->d_sb);
-}
-
static void remove_dir(struct dentry *d)
{
struct dentry *parent = dget(d->d_parent);
@@ -1542,7 +1537,6 @@ static int cgroup_get_rootdir(struct super_block *sb)
static const struct dentry_operations cgroup_dops = {
.d_iput = cgroup_diput,
.d_delete = cgroup_delete,
- .d_release = cgroup_d_release,
};
struct inode *inode =
@@ -3889,8 +3883,12 @@ static void css_dput_fn(struct work_struct *work)
{
struct cgroup_subsys_state *css =
container_of(work, struct cgroup_subsys_state, dput_work);
+ struct dentry *dentry = css->cgroup->dentry;
+ struct super_block *sb = dentry->d_sb;
- dput(css->cgroup->dentry);
+ atomic_inc(&sb->s_active);
+ dput(dentry);
+ deactivate_super(sb);
}
static void init_cgroup_css(struct cgroup_subsys_state *css,
@@ -4982,10 +4980,12 @@ EXPORT_SYMBOL_GPL(__css_tryget);
void __css_put(struct cgroup_subsys_state *css)
{
struct cgroup *cgrp = css->cgroup;
+ int v;
rcu_read_lock();
- atomic_dec(&css->refcnt);
- switch (css_refcnt(css)) {
+ v = css_unbias_refcnt(atomic_dec_return(&css->refcnt));
+
+ switch (v) {
case 1:
if (notify_on_release(cgrp)) {
set_bit(CGRP_RELEASABLE, &cgrp->flags);