diff options
Diffstat (limited to 'kernel/cgroup.c')
| -rw-r--r-- | kernel/cgroup.c | 28 |
1 files changed, 8 insertions, 20 deletions
diff --git a/kernel/cgroup.c b/kernel/cgroup.c index 4936d8886b4..82288088f6a 100644 --- a/kernel/cgroup.c +++ b/kernel/cgroup.c @@ -1850,14 +1850,12 @@ static int cgroup_task_migrate(struct cgroup *cgrp, struct cgroup *oldcgrp, struct css_set *newcg; /* - * get old css_set. We are synchronized through threadgroup_lock() - * against PF_EXITING setting such that we can't race against - * cgroup_exit() changing the css_set to init_css_set and dropping the - * old one. + * We are synchronized through threadgroup_lock() against PF_EXITING + * setting such that we can't race against cgroup_exit() changing the + * css_set to init_css_set and dropping the old one. */ WARN_ON_ONCE(tsk->flags & PF_EXITING); oldcg = tsk->cgroups; - get_css_set(oldcg); /* locate or allocate a new css_set for this task. */ if (guarantee) { @@ -1872,12 +1870,9 @@ static int cgroup_task_migrate(struct cgroup *cgrp, struct cgroup *oldcgrp, might_sleep(); /* find_css_set will give us newcg already referenced. */ newcg = find_css_set(oldcg, cgrp); - if (!newcg) { - put_css_set(oldcg); + if (!newcg) return -ENOMEM; - } } - put_css_set(oldcg); task_lock(tsk); rcu_assign_pointer(tsk->cgroups, newcg); @@ -2186,18 +2181,11 @@ int cgroup_attach_proc(struct cgroup *cgrp, struct task_struct *leader) * init_css_set. */ oldcg = tc->task->cgroups; - get_css_set(oldcg); - /* see if the new one for us is already in the list? */ - if (css_set_check_fetched(cgrp, tc->task, oldcg, &newcg_list)) { - /* was already there, nothing to do. */ - put_css_set(oldcg); - } else { - /* we don't already have it. get new one. */ - retval = css_set_prefetch(cgrp, oldcg, &newcg_list); - put_css_set(oldcg); - if (retval) + + /* if we don't already have it in the list get a new one */ + if (!css_set_check_fetched(cgrp, tc->task, oldcg, &newcg_list)) + if (retval = css_set_prefetch(cgrp, oldcg, &newcg_list)) goto out_list_teardown; - } } /* |