cgroup: rename CGRP_REMOVED to CGRP_DEAD

We will add another flag indicating that the cgroup is in the process
of being killed.  REMOVING / REMOVED is more difficult to distinguish
and cgroup_is_removing()/cgroup_is_removed() are a bit awkward.  Also,
later percpu_ref usage will involve "kill"ing the refcnt.

 s/CGRP_REMOVED/CGRP_DEAD/
 s/cgroup_is_removed()/cgroup_is_dead()

This patch is purely cosmetic.

Signed-off-by: Tejun Heo <tj@kernel.org>
Acked-by: Li Zefan <lizefan@huawei.com>

diff --git a/include/linux/cgroup.h b/include/linux/cgroup.h
index a494636..c86a93a 100644 (file)
--- a/include/linux/cgroup.h
+++ b/include/linux/cgroup.h
@@ -143,7 +143,7 @@ static inline void css_put(struct cgroup_subsys_state *css)
 /* bits in struct cgroup flags field */
 enum {
        /* Control Group is dead */
-       CGRP_REMOVED,
+       CGRP_DEAD,
        /*
         * Control Group has previously had a child cgroup or a task,
         * but no longer (only if CGRP_NOTIFY_ON_RELEASE is set)

diff --git a/kernel/cgroup.c b/kernel/cgroup.c
index d86a847..84efb34 100644 (file)
--- a/kernel/cgroup.c
+++ b/kernel/cgroup.c
@@ -226,9 +226,9 @@ static int css_refcnt(struct cgroup_subsys_state *css)
 }
 
 /* convenient tests for these bits */
-static inline bool cgroup_is_removed(const struct cgroup *cgrp)
+static inline bool cgroup_is_dead(const struct cgroup *cgrp)
 {
-       return test_bit(CGRP_REMOVED, &cgrp->flags);
+       return test_bit(CGRP_DEAD, &cgrp->flags);
 }
 
 /**
@@ -300,7 +300,7 @@ static inline struct cftype *__d_cft(struct dentry *dentry)
 static bool cgroup_lock_live_group(struct cgroup *cgrp)
 {
        mutex_lock(&cgroup_mutex);
-       if (cgroup_is_removed(cgrp)) {
+       if (cgroup_is_dead(cgrp)) {
                mutex_unlock(&cgroup_mutex);
                return false;
        }
@@ -892,7 +892,7 @@ static void cgroup_diput(struct dentry *dentry, struct inode *inode)
        if (S_ISDIR(inode->i_mode)) {
                struct cgroup *cgrp = dentry->d_fsdata;
 
-               BUG_ON(!(cgroup_is_removed(cgrp)));
+               BUG_ON(!(cgroup_is_dead(cgrp)));
                call_rcu(&cgrp->rcu_head, cgroup_free_rcu);
        } else {
                struct cfent *cfe = __d_cfe(dentry);
@@ -2363,7 +2363,7 @@ static ssize_t cgroup_file_write(struct file *file, const char __user *buf,
        struct cftype *cft = __d_cft(file->f_dentry);
        struct cgroup *cgrp = __d_cgrp(file->f_dentry->d_parent);
 
-       if (cgroup_is_removed(cgrp))
+       if (cgroup_is_dead(cgrp))
                return -ENODEV;
        if (cft->write)
                return cft->write(cgrp, cft, file, buf, nbytes, ppos);
@@ -2408,7 +2408,7 @@ static ssize_t cgroup_file_read(struct file *file, char __user *buf,
        struct cftype *cft = __d_cft(file->f_dentry);
        struct cgroup *cgrp = __d_cgrp(file->f_dentry->d_parent);
 
-       if (cgroup_is_removed(cgrp))
+       if (cgroup_is_dead(cgrp))
                return -ENODEV;
 
        if (cft->read)
@@ -2831,7 +2831,7 @@ static void cgroup_cfts_commit(struct cgroup_subsys *ss,
 
                mutex_lock(&inode->i_mutex);
                mutex_lock(&cgroup_mutex);
-               if (!cgroup_is_removed(cgrp))
+               if (!cgroup_is_dead(cgrp))
                        cgroup_addrm_files(cgrp, ss, cfts, is_add);
                mutex_unlock(&cgroup_mutex);
                mutex_unlock(&inode->i_mutex);
@@ -2999,14 +2999,14 @@ struct cgroup *cgroup_next_sibling(struct cgroup *pos)
        /*
         * @pos could already have been removed.  Once a cgroup is removed,
         * its ->sibling.next is no longer updated when its next sibling
-        * changes.  As CGRP_REMOVED is set on removal which is fully
+        * changes.  As CGRP_DEAD is set on removal which is fully
         * serialized, if we see it unasserted, it's guaranteed that the
         * next sibling hasn't finished its grace period even if it's
         * already removed, and thus safe to dereference from this RCU
         * critical section.  If ->sibling.next is inaccessible,
-        * cgroup_is_removed() is guaranteed to be visible as %true here.
+        * cgroup_is_dead() is guaranteed to be visible as %true here.
         */
-       if (likely(!cgroup_is_removed(pos))) {
+       if (likely(!cgroup_is_dead(pos))) {
                next = list_entry_rcu(pos->sibling.next, struct cgroup, sibling);
                if (&next->sibling != &pos->parent->children)
                        return next;
@@ -4383,7 +4383,7 @@ static int cgroup_destroy_locked(struct cgroup *cgrp)
         * attempts fail thus maintaining the removal conditions verified
         * above.
         *
-        * Note that CGRP_REMVOED clearing is depended upon by
+        * Note that CGRP_DEAD assertion is depended upon by
         * cgroup_next_sibling() to resume iteration after dropping RCU
         * read lock.  See cgroup_next_sibling() for details.
         */
@@ -4393,7 +4393,7 @@ static int cgroup_destroy_locked(struct cgroup *cgrp)
                WARN_ON(atomic_read(&css->refcnt) < 0);
                atomic_add(CSS_DEACT_BIAS, &css->refcnt);
        }
-       set_bit(CGRP_REMOVED, &cgrp->flags);
+       set_bit(CGRP_DEAD, &cgrp->flags);
 
        /* tell subsystems to initate destruction */
        for_each_subsys(cgrp->root, ss)
@@ -5063,7 +5063,7 @@ static void check_for_release(struct cgroup *cgrp)
                int need_schedule_work = 0;
 
                raw_spin_lock(&release_list_lock);
-               if (!cgroup_is_removed(cgrp) &&
+               if (!cgroup_is_dead(cgrp) &&
                    list_empty(&cgrp->release_list)) {
                        list_add(&cgrp->release_list, &release_list);
                        need_schedule_work = 1;
@@ -5209,9 +5209,7 @@ __setup("cgroup_disable=", cgroup_disable);
  * Functons for CSS ID.
  */
 
-/*
- *To get ID other than 0, this should be called when !cgroup_is_removed().
- */
+/* to get ID other than 0, this should be called when !cgroup_is_dead() */
 unsigned short css_id(struct cgroup_subsys_state *css)
 {
        struct css_id *cssid;