From 9d800df12d31734a6853915e9d2deb5d6747985f Mon Sep 17 00:00:00 2001 From: Tejun Heo Date: Wed, 14 May 2014 09:15:00 -0400 Subject: [PATCH] cgroup: rename cgroup->dummy_css to ->self and move it to the top cgroup->dummy_css is used as the placeholder css when performing css oriended operations on the cgroup. We're gonna shift more cgroup management to this css. Let's rename it to ->self and move it to the top. This is pure rename and field relocation. Signed-off-by: Tejun Heo Acked-by: Li Zefan --- include/linux/cgroup.h | 6 +++--- kernel/cgroup.c | 20 ++++++++++---------- 2 files changed, 13 insertions(+), 13 deletions(-) diff --git a/include/linux/cgroup.h b/include/linux/cgroup.h index aa7353deaaf3..164851e388e7 100644 --- a/include/linux/cgroup.h +++ b/include/linux/cgroup.h @@ -143,6 +143,9 @@ enum { }; struct cgroup { + /* self css with NULL ->ss, points back to this cgroup */ + struct cgroup_subsys_state self; + unsigned long flags; /* "unsigned long" so bitops work */ /* @@ -224,9 +227,6 @@ struct cgroup { struct list_head pidlists; struct mutex pidlist_mutex; - /* dummy css with NULL ->ss, points back to this cgroup */ - struct cgroup_subsys_state dummy_css; - /* For css percpu_ref killing and RCU-protected deletion */ struct rcu_head rcu_head; struct work_struct destroy_work; diff --git a/kernel/cgroup.c b/kernel/cgroup.c index f36fd9c15b3a..b57a949ae4bc 100644 --- a/kernel/cgroup.c +++ b/kernel/cgroup.c @@ -220,7 +220,7 @@ static void cgroup_idr_remove(struct idr *idr, int id) /** * cgroup_css - obtain a cgroup's css for the specified subsystem * @cgrp: the cgroup of interest - * @ss: the subsystem of interest (%NULL returns the dummy_css) + * @ss: the subsystem of interest (%NULL returns @cgrp->self) * * Return @cgrp's css (cgroup_subsys_state) associated with @ss. This * function must be called either under cgroup_mutex or rcu_read_lock() and @@ -235,13 +235,13 @@ static struct cgroup_subsys_state *cgroup_css(struct cgroup *cgrp, return rcu_dereference_check(cgrp->subsys[ss->id], lockdep_is_held(&cgroup_mutex)); else - return &cgrp->dummy_css; + return &cgrp->self; } /** * cgroup_e_css - obtain a cgroup's effective css for the specified subsystem * @cgrp: the cgroup of interest - * @ss: the subsystem of interest (%NULL returns the dummy_css) + * @ss: the subsystem of interest (%NULL returns @cgrp->self) * * Similar to cgroup_css() but returns the effctive css, which is defined * as the matching css of the nearest ancestor including self which has @ss @@ -254,7 +254,7 @@ static struct cgroup_subsys_state *cgroup_e_css(struct cgroup *cgrp, lockdep_assert_held(&cgroup_mutex); if (!ss) - return &cgrp->dummy_css; + return &cgrp->self; if (!(cgrp->root->subsys_mask & (1 << ss->id))) return NULL; @@ -288,7 +288,7 @@ struct cgroup_subsys_state *of_css(struct kernfs_open_file *of) if (cft->ss) return rcu_dereference_raw(cgrp->subsys[cft->ss->id]); else - return &cgrp->dummy_css; + return &cgrp->self; } EXPORT_SYMBOL_GPL(of_css); @@ -1551,7 +1551,7 @@ static void init_cgroup_housekeeping(struct cgroup *cgrp) INIT_LIST_HEAD(&cgrp->release_list); INIT_LIST_HEAD(&cgrp->pidlists); mutex_init(&cgrp->pidlist_mutex); - cgrp->dummy_css.cgroup = cgrp; + cgrp->self.cgroup = cgrp; for_each_subsys(ss, ssid) INIT_LIST_HEAD(&cgrp->e_csets[ssid]); @@ -3454,7 +3454,7 @@ int cgroup_transfer_tasks(struct cgroup *to, struct cgroup *from) * ->can_attach() fails. */ do { - css_task_iter_start(&from->dummy_css, &it); + css_task_iter_start(&from->self, &it); task = css_task_iter_next(&it); if (task) get_task_struct(task); @@ -3719,7 +3719,7 @@ static int pidlist_array_load(struct cgroup *cgrp, enum cgroup_filetype type, if (!array) return -ENOMEM; /* now, populate the array */ - css_task_iter_start(&cgrp->dummy_css, &it); + css_task_iter_start(&cgrp->self, &it); while ((tsk = css_task_iter_next(&it))) { if (unlikely(n == length)) break; @@ -3793,7 +3793,7 @@ int cgroupstats_build(struct cgroupstats *stats, struct dentry *dentry) } rcu_read_unlock(); - css_task_iter_start(&cgrp->dummy_css, &it); + css_task_iter_start(&cgrp->self, &it); while ((tsk = css_task_iter_next(&it))) { switch (tsk->state) { case TASK_RUNNING: @@ -4274,7 +4274,7 @@ static int cgroup_mkdir(struct kernfs_node *parent_kn, const char *name, init_cgroup_housekeeping(cgrp); cgrp->parent = parent; - cgrp->dummy_css.parent = &parent->dummy_css; + cgrp->self.parent = &parent->self; cgrp->root = root; if (notify_on_release(parent)) -- 2.20.1