From 54766d4a1d3d6f84ff8fa475cd8f165c0a0000eb Mon Sep 17 00:00:00 2001 From: Tejun Heo Date: Wed, 12 Jun 2013 21:04:53 -0700 Subject: [PATCH] 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 Acked-by: Li Zefan --- include/linux/cgroup.h | 2 +- kernel/cgroup.c | 30 ++++++++++++++---------------- 2 files changed, 15 insertions(+), 17 deletions(-) diff --git a/include/linux/cgroup.h b/include/linux/cgroup.h index a494636a34da..c86a93abe83d 100644 --- 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 d86a8477d56a..84efb344fdf6 100644 --- 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; -- GitLab