diff options
| -rw-r--r-- | drivers/vhost/vhost.c | 80 | ||||
| -rw-r--r-- | include/linux/cgroup.h | 11 | ||||
| -rw-r--r-- | kernel/cgroup.c | 9 |
3 files changed, 73 insertions, 27 deletions
diff --git a/drivers/vhost/vhost.c b/drivers/vhost/vhost.c index 4b99117f3ecd..c579dcc9200c 100644 --- a/drivers/vhost/vhost.c +++ b/drivers/vhost/vhost.c @@ -60,22 +60,25 @@ static int vhost_poll_wakeup(wait_queue_t *wait, unsigned mode, int sync, return 0; } +static void vhost_work_init(struct vhost_work *work, vhost_work_fn_t fn) +{ + INIT_LIST_HEAD(&work->node); + work->fn = fn; + init_waitqueue_head(&work->done); + work->flushing = 0; + work->queue_seq = work->done_seq = 0; +} + /* Init poll structure */ void vhost_poll_init(struct vhost_poll *poll, vhost_work_fn_t fn, unsigned long mask, struct vhost_dev *dev) { - struct vhost_work *work = &poll->work; - init_waitqueue_func_entry(&poll->wait, vhost_poll_wakeup); init_poll_funcptr(&poll->table, vhost_poll_func); poll->mask = mask; poll->dev = dev; - INIT_LIST_HEAD(&work->node); - work->fn = fn; - init_waitqueue_head(&work->done); - work->flushing = 0; - work->queue_seq = work->done_seq = 0; + vhost_work_init(&poll->work, fn); } /* Start polling a file. We add ourselves to file's wait queue. The caller must @@ -95,35 +98,38 @@ void vhost_poll_stop(struct vhost_poll *poll) remove_wait_queue(poll->wqh, &poll->wait); } -/* Flush any work that has been scheduled. When calling this, don't hold any - * locks that are also used by the callback. */ -void vhost_poll_flush(struct vhost_poll *poll) +static void vhost_work_flush(struct vhost_dev *dev, struct vhost_work *work) { - struct vhost_work *work = &poll->work; unsigned seq; int left; int flushing; - spin_lock_irq(&poll->dev->work_lock); + spin_lock_irq(&dev->work_lock); seq = work->queue_seq; work->flushing++; - spin_unlock_irq(&poll->dev->work_lock); + spin_unlock_irq(&dev->work_lock); wait_event(work->done, ({ - spin_lock_irq(&poll->dev->work_lock); + spin_lock_irq(&dev->work_lock); left = seq - work->done_seq <= 0; - spin_unlock_irq(&poll->dev->work_lock); + spin_unlock_irq(&dev->work_lock); left; })); - spin_lock_irq(&poll->dev->work_lock); + spin_lock_irq(&dev->work_lock); flushing = --work->flushing; - spin_unlock_irq(&poll->dev->work_lock); + spin_unlock_irq(&dev->work_lock); BUG_ON(flushing < 0); } -void vhost_poll_queue(struct vhost_poll *poll) +/* Flush any work that has been scheduled. When calling this, don't hold any + * locks that are also used by the callback. */ +void vhost_poll_flush(struct vhost_poll *poll) +{ + vhost_work_flush(poll->dev, &poll->work); +} + +static inline void vhost_work_queue(struct vhost_dev *dev, + struct vhost_work *work) { - struct vhost_dev *dev = poll->dev; - struct vhost_work *work = &poll->work; unsigned long flags; spin_lock_irqsave(&dev->work_lock, flags); @@ -135,6 +141,11 @@ void vhost_poll_queue(struct vhost_poll *poll) spin_unlock_irqrestore(&dev->work_lock, flags); } +void vhost_poll_queue(struct vhost_poll *poll) +{ + vhost_work_queue(poll->dev, &poll->work); +} + static void vhost_vq_reset(struct vhost_dev *dev, struct vhost_virtqueue *vq) { @@ -236,6 +247,29 @@ long vhost_dev_check_owner(struct vhost_dev *dev) return dev->mm == current->mm ? 0 : -EPERM; } +struct vhost_attach_cgroups_struct { + struct vhost_work work; + struct task_struct *owner; + int ret; +}; + +static void vhost_attach_cgroups_work(struct vhost_work *work) +{ + struct vhost_attach_cgroups_struct *s; + s = container_of(work, struct vhost_attach_cgroups_struct, work); + s->ret = cgroup_attach_task_all(s->owner, current); +} + +static int vhost_attach_cgroups(struct vhost_dev *dev) +{ + struct vhost_attach_cgroups_struct attach; + attach.owner = current; + vhost_work_init(&attach.work, vhost_attach_cgroups_work); + vhost_work_queue(dev, &attach.work); + vhost_work_flush(dev, &attach.work); + return attach.ret; +} + /* Caller should have device mutex */ static long vhost_dev_set_owner(struct vhost_dev *dev) { @@ -255,14 +289,16 @@ static long vhost_dev_set_owner(struct vhost_dev *dev) } dev->worker = worker; - err = cgroup_attach_task_current_cg(worker); + wake_up_process(worker); /* avoid contributing to loadavg */ + + err = vhost_attach_cgroups(dev); if (err) goto err_cgroup; - wake_up_process(worker); /* avoid contributing to loadavg */ return 0; err_cgroup: kthread_stop(worker); + dev->worker = NULL; err_worker: if (dev->mm) mmput(dev->mm); diff --git a/include/linux/cgroup.h b/include/linux/cgroup.h index ed3e92e41c6e..5a53d8f039a2 100644 --- a/include/linux/cgroup.h +++ b/include/linux/cgroup.h @@ -578,7 +578,11 @@ struct task_struct *cgroup_iter_next(struct cgroup *cgrp, void cgroup_iter_end(struct cgroup *cgrp, struct cgroup_iter *it); int cgroup_scan_tasks(struct cgroup_scanner *scan); int cgroup_attach_task(struct cgroup *, struct task_struct *); -int cgroup_attach_task_current_cg(struct task_struct *); +int cgroup_attach_task_all(struct task_struct *from, struct task_struct *); +static inline int cgroup_attach_task_current_cg(struct task_struct *tsk) +{ + return cgroup_attach_task_all(current, tsk); +} /* * CSS ID is ID for cgroup_subsys_state structs under subsys. This only works @@ -636,6 +640,11 @@ static inline int cgroupstats_build(struct cgroupstats *stats, } /* No cgroups - nothing to do */ +static inline int cgroup_attach_task_all(struct task_struct *from, + struct task_struct *t) +{ + return 0; +} static inline int cgroup_attach_task_current_cg(struct task_struct *t) { return 0; diff --git a/kernel/cgroup.c b/kernel/cgroup.c index 192f88c5b0f9..ed19afd9e3fe 100644 --- a/kernel/cgroup.c +++ b/kernel/cgroup.c @@ -1791,10 +1791,11 @@ out: } /** - * cgroup_attach_task_current_cg - attach task 'tsk' to current task's cgroup + * cgroup_attach_task_all - attach task 'tsk' to all cgroups of task 'from' + * @from: attach to all cgroups of a given task * @tsk: the task to be attached */ -int cgroup_attach_task_current_cg(struct task_struct *tsk) +int cgroup_attach_task_all(struct task_struct *from, struct task_struct *tsk) { struct cgroupfs_root *root; struct cgroup *cur_cg; @@ -1802,7 +1803,7 @@ int cgroup_attach_task_current_cg(struct task_struct *tsk) cgroup_lock(); for_each_active_root(root) { - cur_cg = task_cgroup_from_root(current, root); + cur_cg = task_cgroup_from_root(from, root); retval = cgroup_attach_task(cur_cg, tsk); if (retval) break; @@ -1811,7 +1812,7 @@ int cgroup_attach_task_current_cg(struct task_struct *tsk) return retval; } -EXPORT_SYMBOL_GPL(cgroup_attach_task_current_cg); +EXPORT_SYMBOL_GPL(cgroup_attach_task_all); /* * Attach task with pid 'pid' to cgroup 'cgrp'. Call with cgroup_mutex |