From b7fc5ad235936379fae67a9f7b50bb53487a1a3a Mon Sep 17 00:00:00 2001 From: Tejun Heo Date: Tue, 13 May 2014 12:16:22 -0400 Subject: [PATCH] cgroup: remove cgroup->control_kn Now that cgroup_subtree_control_write() has access to the associated kernfs_open_file and thus the kernfs_node, there's no need to cache it in cgroup->control_kn on creation. Remove cgroup->control_kn and use @of->kn directly. Signed-off-by: Tejun Heo Acked-by: Li Zefan --- include/linux/cgroup.h | 1 - kernel/cgroup.c | 8 +++----- 2 files changed, 3 insertions(+), 6 deletions(-) diff --git a/include/linux/cgroup.h b/include/linux/cgroup.h index 08eb71ee600..aa7353deaaf 100644 --- a/include/linux/cgroup.h +++ b/include/linux/cgroup.h @@ -177,7 +177,6 @@ struct cgroup { struct cgroup *parent; /* my parent */ struct kernfs_node *kn; /* cgroup kernfs entry */ - struct kernfs_node *control_kn; /* kn for "cgroup.subtree_control" */ struct kernfs_node *populated_kn; /* kn for "cgroup.subtree_populated" */ /* diff --git a/kernel/cgroup.c b/kernel/cgroup.c index 9a48c117ebf..94d259bcd2b 100644 --- a/kernel/cgroup.c +++ b/kernel/cgroup.c @@ -2580,7 +2580,7 @@ static ssize_t cgroup_subtree_control_write(struct kernfs_open_file *of, * active_ref protection. */ cgroup_get(cgrp); - kernfs_break_active_protection(cgrp->control_kn); + kernfs_break_active_protection(of->kn); mutex_lock(&cgroup_tree_mutex); @@ -2697,7 +2697,7 @@ out_unlock: out_unlock_tree: mutex_unlock(&cgroup_tree_mutex); out_unbreak: - kernfs_unbreak_active_protection(cgrp->control_kn); + kernfs_unbreak_active_protection(of->kn); cgroup_put(cgrp); return ret ?: nbytes; @@ -2887,9 +2887,7 @@ static int cgroup_add_file(struct cgroup *cgrp, struct cftype *cft) return ret; } - if (cft->seq_show == cgroup_subtree_control_show) - cgrp->control_kn = kn; - else if (cft->seq_show == cgroup_populated_show) + if (cft->seq_show == cgroup_populated_show) cgrp->populated_kn = kn; return 0; } -- 2.41.0