diff options
| -rw-r--r-- | include/linux/cgroup.h | 3 | ||||
| -rw-r--r-- | kernel/cgroup.c | 62 |
2 files changed, 6 insertions, 59 deletions
diff --git a/include/linux/cgroup.h b/include/linux/cgroup.h index 164851e..160fcc6 100644 --- a/include/linux/cgroup.h +++ b/include/linux/cgroup.h @@ -158,9 +158,6 @@ struct cgroup { */ int id; - /* the number of attached css's */ - int nr_css; - /* * If this cgroup contains any tasks, it contributes one to * populated_cnt. All children with non-zero popuplated_cnt of diff --git a/kernel/cgroup.c b/kernel/cgroup.c index e9aa2a5..4a94b0b 100644 --- a/kernel/cgroup.c +++ b/kernel/cgroup.c @@ -178,7 +178,6 @@ static struct cftype cgroup_base_files[]; static void cgroup_put(struct cgroup *cgrp); static int rebind_subsystems(struct cgroup_root *dst_root, unsigned int ss_mask); -static void cgroup_destroy_css_killed(struct cgroup *cgrp); static int cgroup_destroy_locked(struct cgroup *cgrp); static int create_css(struct cgroup *cgrp, struct cgroup_subsys *ss); static void kill_css(struct cgroup_subsys_state *css); @@ -4169,7 +4168,6 @@ static int online_css(struct cgroup_subsys_state *css) ret = ss->css_online(css); if (!ret) { css->flags |= CSS_ONLINE; - css->cgroup->nr_css++; rcu_assign_pointer(css->cgroup->subsys[ss->id], css); } return ret; @@ -4189,7 +4187,6 @@ static void offline_css(struct cgroup_subsys_state *css) ss->css_offline(css); css->flags &= ~CSS_ONLINE; - css->cgroup->nr_css--; RCU_INIT_POINTER(css->cgroup->subsys[ss->id], NULL); wake_up_all(&css->cgroup->offline_waitq); @@ -4374,39 +4371,18 @@ out_destroy: /* * This is called when the refcnt of a css is confirmed to be killed. - * css_tryget_online() is now guaranteed to fail. + * css_tryget_online() is now guaranteed to fail. Tell the subsystem to + * initate destruction and put the css ref from kill_css(). */ static void css_killed_work_fn(struct work_struct *work) { struct cgroup_subsys_state *css = container_of(work, struct cgroup_subsys_state, destroy_work); - struct cgroup *cgrp = css->cgroup; mutex_lock(&cgroup_mutex); - - /* - * css_tryget_online() is guaranteed to fail now. Tell subsystems - * to initate destruction. - */ offline_css(css); - - /* - * If @cgrp is marked dead, it's waiting for refs of all css's to - * be disabled before proceeding to the second phase of cgroup - * destruction. If we are the last one, kick it off. - */ - if (!cgrp->nr_css && cgroup_is_dead(cgrp)) - cgroup_destroy_css_killed(cgrp); - mutex_unlock(&cgroup_mutex); - /* - * Put the css refs from kill_css(). Each css holds an extra - * reference to the cgroup's dentry and cgroup removal proceeds - * regardless of css refs. On the last put of each css, whenever - * that may be, the extra dentry ref is put so that dentry - * destruction happens only after all css's are released. - */ css_put(css); } @@ -4518,11 +4494,7 @@ static int cgroup_destroy_locked(struct cgroup *cgrp) */ set_bit(CGRP_DEAD, &cgrp->flags); - /* - * Initiate massacre of all css's. cgroup_destroy_css_killed() - * will be invoked to perform the rest of destruction once the - * percpu refs of all css's are confirmed to be killed. - */ + /* initiate massacre of all css's */ for_each_css(css, ssid, cgrp) kill_css(css); @@ -4533,15 +4505,6 @@ static int cgroup_destroy_locked(struct cgroup *cgrp) raw_spin_unlock(&release_list_lock); /* - * If @cgrp has css's attached, the second stage of cgroup - * destruction is kicked off from css_killed_work_fn() after the - * refs of all attached css's are killed. If @cgrp doesn't have - * any css, we kick it off here. - */ - if (!cgrp->nr_css) - cgroup_destroy_css_killed(cgrp); - - /* * Remove @cgrp directory along with the base files. @cgrp has an * extra ref on its kn. */ @@ -4550,25 +4513,12 @@ static int cgroup_destroy_locked(struct cgroup *cgrp) set_bit(CGRP_RELEASABLE, &cgrp->parent->flags); check_for_release(cgrp->parent); + /* put the base reference */ + cgroup_put(cgrp); + return 0; }; -/** - * cgroup_destroy_css_killed - the second step of cgroup destruction - * @cgrp: the cgroup whose csses have just finished offlining - * - * This function is invoked from a work item for a cgroup which is being - * destroyed after all css's are offlined and performs the rest of - * destruction. This is the second step of destruction described in the - * comment above cgroup_destroy_locked(). - */ -static void cgroup_destroy_css_killed(struct cgroup *cgrp) -{ - lockdep_assert_held(&cgroup_mutex); - - cgroup_put(cgrp); -} - static int cgroup_rmdir(struct kernfs_node *kn) { struct cgroup *cgrp; |
