Remove unnecessary file

device/linux-sharp-shl22/update_cgroup.patch

-diff --git a/kernel/cgroup.c b/kernel/cgroup.c
-index 2f0d7542..a2c812ec 100644
---- a/kernel/cgroup.c
-+++ b/kernel/cgroup.c
-@@ -385,10 +385,18 @@ static void free_css_set_work(struct work_struct *work)
- 		struct cgroup *cgrp = link->cgrp;
- 		list_del(&link->cg_link_list);
- 		list_del(&link->cgrp_link_list);
-+
-+		/*
-+		 * We may not be holding cgroup_mutex, and if cgrp->count is
-+		 * dropped to 0 the cgroup can be destroyed at any time, hence
-+		 * rcu_read_lock is used to keep it alive.
-+		 */
-+		rcu_read_lock();
- 		if (atomic_dec_and_test(&cgrp->count)) {
- 			check_for_release(cgrp);
- 			cgroup_wakeup_rmdir_waiter(cgrp);
- 		}
-+		rcu_read_unlock();
- 		kfree(link);
- 	}
- 	write_unlock(&css_set_lock);
-@@ -1871,9 +1879,8 @@ static void cgroup_task_migrate(struct cgroup *cgrp, struct cgroup *oldcgrp,
- 	 * trading it for newcg is protected by cgroup_mutex, we're safe to drop
- 	 * it here; it will be freed under RCU.
- 	 */
--	put_css_set(oldcg);
--
- 	set_bit(CGRP_RELEASABLE, &oldcgrp->flags);
-+	put_css_set(oldcg);
- }
- 
- /**
-@@ -2023,7 +2030,7 @@ static int cgroup_attach_proc(struct cgroup *cgrp, struct task_struct *leader)
- 	if (!group)
- 		return -ENOMEM;
- 	/* pre-allocate to guarantee space while iterating in rcu read-side. */
--	retval = flex_array_prealloc(group, 0, group_size - 1, GFP_KERNEL);
-+	retval = flex_array_prealloc(group, 0, group_size, GFP_KERNEL);
- 	if (retval)
- 		goto out_free_group_list;
- 
-@@ -2606,9 +2613,7 @@ static int cgroup_create_dir(struct cgroup *cgrp, struct dentry *dentry,
- 		dentry->d_fsdata = cgrp;
- 		inc_nlink(parent->d_inode);
- 		rcu_assign_pointer(cgrp->dentry, dentry);
--		dget(dentry);
- 	}
--	dput(dentry);
- 
- 	return error;
- }
-@@ -3508,6 +3513,7 @@ static int cgroup_write_event_control(struct cgroup *cgrp, struct cftype *cft,
- 				      const char *buffer)
- {
- 	struct cgroup_event *event = NULL;
-+	struct cgroup *cgrp_cfile;
- 	unsigned int efd, cfd;
- 	struct file *efile = NULL;
- 	struct file *cfile = NULL;
-@@ -3563,6 +3569,16 @@ static int cgroup_write_event_control(struct cgroup *cgrp, struct cftype *cft,
- 		goto fail;
- 	}
- 
-+	/*
-+	 * The file to be monitored must be in the same cgroup as
-+	 * cgroup.event_control is.
-+	 */
-+	cgrp_cfile = __d_cgrp(cfile->f_dentry->d_parent);
-+	if (cgrp_cfile != cgrp) {
-+		ret = -EINVAL;
-+		goto fail;
-+	}
-+
- 	if (!event->cft->register_event || !event->cft->unregister_event) {
- 		ret = -EINVAL;
- 		goto fail;
-@@ -4516,31 +4532,20 @@ static const struct file_operations proc_cgroupstats_operations = {
-  *
-  * A pointer to the shared css_set was automatically copied in
-  * fork.c by dup_task_struct().  However, we ignore that copy, since
-- * it was not made under the protection of RCU, cgroup_mutex or
-- * threadgroup_change_begin(), so it might no longer be a valid
-- * cgroup pointer.  cgroup_attach_task() might have already changed
-- * current->cgroups, allowing the previously referenced cgroup
-- * group to be removed and freed.
-- *
-- * Outside the pointer validity we also need to process the css_set
-- * inheritance between threadgoup_change_begin() and
-- * threadgoup_change_end(), this way there is no leak in any process
-- * wide migration performed by cgroup_attach_proc() that could otherwise
-- * miss a thread because it is too early or too late in the fork stage.
-+ * it was not made under the protection of RCU or cgroup_mutex, so
-+ * might no longer be a valid cgroup pointer.  cgroup_attach_task() might
-+ * have already changed current->cgroups, allowing the previously
-+ * referenced cgroup group to be removed and freed.
-  *
-  * At the point that cgroup_fork() is called, 'current' is the parent
-  * task, and the passed argument 'child' points to the child task.
-  */
- void cgroup_fork(struct task_struct *child)
- {
--	/*
--	 * We don't need to task_lock() current because current->cgroups
--	 * can't be changed concurrently here. The parent obviously hasn't
--	 * exited and called cgroup_exit(), and we are synchronized against
--	 * cgroup migration through threadgroup_change_begin().
--	 */
-+	task_lock(current);
- 	child->cgroups = current->cgroups;
- 	get_css_set(child->cgroups);
-+	task_unlock(current);
- 	INIT_LIST_HEAD(&child->cg_list);
- }
- 
-@@ -4593,19 +4598,10 @@ void cgroup_post_fork(struct task_struct *child)
- 	 */
- 	if (use_task_css_set_links) {
- 		write_lock(&css_set_lock);
--		if (list_empty(&child->cg_list)) {
--			/*
--			 * It's safe to use child->cgroups without task_lock()
--			 * here because we are protected through
--			 * threadgroup_change_begin() against concurrent
--			 * css_set change in cgroup_task_migrate(). Also
--			 * the task can't exit at that point until
--			 * wake_up_new_task() is called, so we are protected
--			 * against cgroup_exit() setting child->cgroup to
--			 * init_css_set.
--			 */
-+		task_lock(child);
-+		if (list_empty(&child->cg_list))
- 			list_add(&child->cg_list, &child->cgroups->tasks);
--		}
-+		task_unlock(child);
- 		write_unlock(&css_set_lock);
- 	}
- }