diff options
Diffstat (limited to 'kernel/cgroup.c')
-rw-r--r-- | kernel/cgroup.c | 57 |
1 files changed, 30 insertions, 27 deletions
diff --git a/kernel/cgroup.c b/kernel/cgroup.c index 1d2b6ceea95..d9d5648f3cd 100644 --- a/kernel/cgroup.c +++ b/kernel/cgroup.c @@ -265,7 +265,7 @@ list_for_each_entry(_root, &roots, root_list) /* the list of cgroups eligible for automatic release. Protected by * release_list_lock */ static LIST_HEAD(release_list); -static DEFINE_SPINLOCK(release_list_lock); +static DEFINE_RAW_SPINLOCK(release_list_lock); static void cgroup_release_agent(struct work_struct *work); static DECLARE_WORK(release_agent_work, cgroup_release_agent); static void check_for_release(struct cgroup *cgrp); @@ -2027,7 +2027,7 @@ int cgroup_attach_proc(struct cgroup *cgrp, struct task_struct *leader) goto out_free_group_list; /* prevent changes to the threadgroup list while we take a snapshot. */ - rcu_read_lock(); + read_lock(&tasklist_lock); if (!thread_group_leader(leader)) { /* * a race with de_thread from another thread's exec() may strip @@ -2036,7 +2036,7 @@ int cgroup_attach_proc(struct cgroup *cgrp, struct task_struct *leader) * throw this task away and try again (from cgroup_procs_write); * this is "double-double-toil-and-trouble-check locking". */ - rcu_read_unlock(); + read_unlock(&tasklist_lock); retval = -EAGAIN; goto out_free_group_list; } @@ -2057,7 +2057,7 @@ int cgroup_attach_proc(struct cgroup *cgrp, struct task_struct *leader) } while_each_thread(leader, tsk); /* remember the number of threads in the array for later. */ group_size = i; - rcu_read_unlock(); + read_unlock(&tasklist_lock); /* * step 1: check that we can legitimately attach to the cgroup. @@ -2135,14 +2135,17 @@ int cgroup_attach_proc(struct cgroup *cgrp, struct task_struct *leader) oldcgrp = task_cgroup_from_root(tsk, root); if (cgrp == oldcgrp) continue; - /* attach each task to each subsystem */ - for_each_subsys(root, ss) { - if (ss->attach_task) - ss->attach_task(cgrp, tsk); - } /* if the thread is PF_EXITING, it can just get skipped. */ retval = cgroup_task_migrate(cgrp, oldcgrp, tsk, true); - BUG_ON(retval != 0 && retval != -ESRCH); + if (retval == 0) { + /* attach each task to each subsystem */ + for_each_subsys(root, ss) { + if (ss->attach_task) + ss->attach_task(cgrp, tsk); + } + } else { + BUG_ON(retval != -ESRCH); + } } /* nothing is sensitive to fork() after this point. */ @@ -4014,11 +4017,11 @@ again: finish_wait(&cgroup_rmdir_waitq, &wait); clear_bit(CGRP_WAIT_ON_RMDIR, &cgrp->flags); - spin_lock(&release_list_lock); + raw_spin_lock(&release_list_lock); set_bit(CGRP_REMOVED, &cgrp->flags); if (!list_empty(&cgrp->release_list)) list_del_init(&cgrp->release_list); - spin_unlock(&release_list_lock); + raw_spin_unlock(&release_list_lock); cgroup_lock_hierarchy(cgrp->root); /* delete this cgroup from parent->children */ @@ -4671,13 +4674,13 @@ static void check_for_release(struct cgroup *cgrp) * already queued for a userspace notification, queue * it now */ int need_schedule_work = 0; - spin_lock(&release_list_lock); + raw_spin_lock(&release_list_lock); if (!cgroup_is_removed(cgrp) && list_empty(&cgrp->release_list)) { list_add(&cgrp->release_list, &release_list); need_schedule_work = 1; } - spin_unlock(&release_list_lock); + raw_spin_unlock(&release_list_lock); if (need_schedule_work) schedule_work(&release_agent_work); } @@ -4729,7 +4732,7 @@ static void cgroup_release_agent(struct work_struct *work) { BUG_ON(work != &release_agent_work); mutex_lock(&cgroup_mutex); - spin_lock(&release_list_lock); + raw_spin_lock(&release_list_lock); while (!list_empty(&release_list)) { char *argv[3], *envp[3]; int i; @@ -4738,7 +4741,7 @@ static void cgroup_release_agent(struct work_struct *work) struct cgroup, release_list); list_del_init(&cgrp->release_list); - spin_unlock(&release_list_lock); + raw_spin_unlock(&release_list_lock); pathbuf = kmalloc(PAGE_SIZE, GFP_KERNEL); if (!pathbuf) goto continue_free; @@ -4768,9 +4771,9 @@ static void cgroup_release_agent(struct work_struct *work) continue_free: kfree(pathbuf); kfree(agentbuf); - spin_lock(&release_list_lock); + raw_spin_lock(&release_list_lock); } - spin_unlock(&release_list_lock); + raw_spin_unlock(&release_list_lock); mutex_unlock(&cgroup_mutex); } @@ -4880,9 +4883,9 @@ void free_css_id(struct cgroup_subsys *ss, struct cgroup_subsys_state *css) rcu_assign_pointer(id->css, NULL); rcu_assign_pointer(css->id, NULL); - spin_lock(&ss->id_lock); + write_lock(&ss->id_lock); idr_remove(&ss->idr, id->id); - spin_unlock(&ss->id_lock); + write_unlock(&ss->id_lock); kfree_rcu(id, rcu_head); } EXPORT_SYMBOL_GPL(free_css_id); @@ -4908,10 +4911,10 @@ static struct css_id *get_new_cssid(struct cgroup_subsys *ss, int depth) error = -ENOMEM; goto err_out; } - spin_lock(&ss->id_lock); + write_lock(&ss->id_lock); /* Don't use 0. allocates an ID of 1-65535 */ error = idr_get_new_above(&ss->idr, newid, 1, &myid); - spin_unlock(&ss->id_lock); + write_unlock(&ss->id_lock); /* Returns error when there are no free spaces for new ID.*/ if (error) { @@ -4926,9 +4929,9 @@ static struct css_id *get_new_cssid(struct cgroup_subsys *ss, int depth) return newid; remove_idr: error = -ENOSPC; - spin_lock(&ss->id_lock); + write_lock(&ss->id_lock); idr_remove(&ss->idr, myid); - spin_unlock(&ss->id_lock); + write_unlock(&ss->id_lock); err_out: kfree(newid); return ERR_PTR(error); @@ -4940,7 +4943,7 @@ static int __init_or_module cgroup_init_idr(struct cgroup_subsys *ss, { struct css_id *newid; - spin_lock_init(&ss->id_lock); + rwlock_init(&ss->id_lock); idr_init(&ss->idr); newid = get_new_cssid(ss, 0); @@ -5035,9 +5038,9 @@ css_get_next(struct cgroup_subsys *ss, int id, * scan next entry from bitmap(tree), tmpid is updated after * idr_get_next(). */ - spin_lock(&ss->id_lock); + read_lock(&ss->id_lock); tmp = idr_get_next(&ss->idr, &tmpid); - spin_unlock(&ss->id_lock); + read_unlock(&ss->id_lock); if (!tmp) break; |