From 320a6a1289a6254ea3768f115536ec57de344767 Mon Sep 17 00:00:00 2001 From: Li Zefan Date: Thu, 24 Jan 2013 14:31:27 +0800 Subject: [PATCH] cgroup: remove duplicate RCU free on struct cgroup When destroying a cgroup, though in cgroup_diput() we've called synchronize_rcu(), we then still have to free it via call_rcu(). The story is, long ago to fix a race between reading /proc/sched_debug and freeing cgroup, the code was changed to utilize call_rcu(). See commit 33ae40136ee28f1ceddb1f69bc791189a0e1d956 ("cgroups: make cgroup_path() RCU-safe") As we've fixed cpu cgroup that cpu_cgroup_offline_css() is used to unregister a task_group so there won't be concurrent access to this task_group after synchronize_rcu() in diput(). Now we can just kfree(cgrp). Signed-off-by: Li Zefan Signed-off-by: Tejun Heo --- kernel/cgroup.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/kernel/cgroup.c b/kernel/cgroup.c index a04932281bc9b..af993919aa041 100644 --- a/kernel/cgroup.c +++ b/kernel/cgroup.c @@ -892,7 +892,7 @@ static void cgroup_diput(struct dentry *dentry, struct inode *inode) simple_xattrs_free(&cgrp->xattrs); ida_simple_remove(&cgrp->root->cgroup_ida, cgrp->id); - kfree_rcu(cgrp, rcu_head); + kfree(cgrp); } else { struct cfent *cfe = __d_cfe(dentry); struct cgroup *cgrp = dentry->d_parent->d_fsdata; -- 2.39.5