On Tue, Sep 21, 2021 at 04:52:17PM -0500, Mike Christie wrote: > This is just a prep patch. It moves the worker related fields to a new > vhost_worker struct and moves the code around to create some helpers that > will be used in the next patches. > > Signed-off-by: Mike Christie <[email protected]> > Reviewed-by: Stefan Hajnoczi <[email protected]>
Acked-by: Michael S. Tsirkin <[email protected]> Feel free to merge with other bits. > --- > drivers/vhost/vhost.c | 98 ++++++++++++++++++++++++++++--------------- > drivers/vhost/vhost.h | 11 +++-- > 2 files changed, 72 insertions(+), 37 deletions(-) > > diff --git a/drivers/vhost/vhost.c b/drivers/vhost/vhost.c > index 59edb5a1ffe2..c9a1f706989c 100644 > --- a/drivers/vhost/vhost.c > +++ b/drivers/vhost/vhost.c > @@ -263,8 +263,8 @@ void vhost_work_queue(struct vhost_dev *dev, struct > vhost_work *work) > * sure it was not in the list. > * test_and_set_bit() implies a memory barrier. > */ > - llist_add(&work->node, &dev->work_list); > - wake_up_process(dev->worker); > + llist_add(&work->node, &dev->worker->work_list); > + wake_up_process(dev->worker->task); > } > } > EXPORT_SYMBOL_GPL(vhost_work_queue); > @@ -272,7 +272,7 @@ EXPORT_SYMBOL_GPL(vhost_work_queue); > /* A lockless hint for busy polling code to exit the loop */ > bool vhost_has_work(struct vhost_dev *dev) > { > - return !llist_empty(&dev->work_list); > + return dev->worker && !llist_empty(&dev->worker->work_list); > } > EXPORT_SYMBOL_GPL(vhost_has_work); > > @@ -343,7 +343,8 @@ static void vhost_vq_reset(struct vhost_dev *dev, > > static int vhost_worker(void *data) > { > - struct vhost_dev *dev = data; > + struct vhost_worker *worker = data; > + struct vhost_dev *dev = worker->dev; > struct vhost_work *work, *work_next; > struct llist_node *node; > > @@ -358,7 +359,7 @@ static int vhost_worker(void *data) > break; > } > > - node = llist_del_all(&dev->work_list); > + node = llist_del_all(&worker->work_list); > if (!node) > schedule(); > > @@ -368,7 +369,7 @@ static int vhost_worker(void *data) > llist_for_each_entry_safe(work, work_next, node, node) { > clear_bit(VHOST_WORK_QUEUED, &work->flags); > __set_current_state(TASK_RUNNING); > - kcov_remote_start_common(dev->kcov_handle); > + kcov_remote_start_common(worker->kcov_handle); > work->fn(work); > kcov_remote_stop(); > if (need_resched()) > @@ -487,7 +488,6 @@ void vhost_dev_init(struct vhost_dev *dev, > dev->byte_weight = byte_weight; > dev->use_worker = use_worker; > dev->msg_handler = msg_handler; > - init_llist_head(&dev->work_list); > init_waitqueue_head(&dev->wait); > INIT_LIST_HEAD(&dev->read_list); > INIT_LIST_HEAD(&dev->pending_list); > @@ -579,10 +579,60 @@ static void vhost_detach_mm(struct vhost_dev *dev) > dev->mm = NULL; > } > > +static void vhost_worker_free(struct vhost_dev *dev) > +{ > + struct vhost_worker *worker = dev->worker; > + > + if (!worker) > + return; > + > + dev->worker = NULL; > + WARN_ON(!llist_empty(&worker->work_list)); > + kthread_stop(worker->task); > + kfree(worker); > +} > + > +static int vhost_worker_create(struct vhost_dev *dev) > +{ > + struct vhost_worker *worker; > + struct task_struct *task; > + int ret; > + > + worker = kzalloc(sizeof(*worker), GFP_KERNEL_ACCOUNT); > + if (!worker) > + return -ENOMEM; > + > + dev->worker = worker; > + worker->dev = dev; > + worker->kcov_handle = kcov_common_handle(); > + init_llist_head(&worker->work_list); > + > + task = kthread_create(vhost_worker, worker, "vhost-%d", current->pid); > + if (IS_ERR(task)) { > + ret = PTR_ERR(task); > + goto free_worker; > + } > + > + worker->task = task; > + wake_up_process(task); /* avoid contributing to loadavg */ > + > + ret = vhost_attach_cgroups(dev); > + if (ret) > + goto stop_worker; > + > + return 0; > + > +stop_worker: > + kthread_stop(worker->task); > +free_worker: > + kfree(worker); > + dev->worker = NULL; > + return ret; > +} > + > /* Caller should have device mutex */ > long vhost_dev_set_owner(struct vhost_dev *dev) > { > - struct task_struct *worker; > int err; > > /* Is there an owner already? */ > @@ -593,36 +643,21 @@ long vhost_dev_set_owner(struct vhost_dev *dev) > > vhost_attach_mm(dev); > > - dev->kcov_handle = kcov_common_handle(); > if (dev->use_worker) { > - worker = kthread_create(vhost_worker, dev, > - "vhost-%d", current->pid); > - if (IS_ERR(worker)) { > - err = PTR_ERR(worker); > - goto err_worker; > - } > - > - dev->worker = worker; > - wake_up_process(worker); /* avoid contributing to loadavg */ > - > - err = vhost_attach_cgroups(dev); > + err = vhost_worker_create(dev); > if (err) > - goto err_cgroup; > + goto err_worker; > } > > err = vhost_dev_alloc_iovecs(dev); > if (err) > - goto err_cgroup; > + goto err_iovecs; > > return 0; > -err_cgroup: > - if (dev->worker) { > - kthread_stop(dev->worker); > - dev->worker = NULL; > - } > +err_iovecs: > + vhost_worker_free(dev); > err_worker: > vhost_detach_mm(dev); > - dev->kcov_handle = 0; > err_mm: > return err; > } > @@ -712,12 +747,7 @@ void vhost_dev_cleanup(struct vhost_dev *dev) > dev->iotlb = NULL; > vhost_clear_msg(dev); > wake_up_interruptible_poll(&dev->wait, EPOLLIN | EPOLLRDNORM); > - WARN_ON(!llist_empty(&dev->work_list)); > - if (dev->worker) { > - kthread_stop(dev->worker); > - dev->worker = NULL; > - dev->kcov_handle = 0; > - } > + vhost_worker_free(dev); > vhost_detach_mm(dev); > } > EXPORT_SYMBOL_GPL(vhost_dev_cleanup); > diff --git a/drivers/vhost/vhost.h b/drivers/vhost/vhost.h > index 638bb640d6b4..102ce25e4e13 100644 > --- a/drivers/vhost/vhost.h > +++ b/drivers/vhost/vhost.h > @@ -25,6 +25,13 @@ struct vhost_work { > unsigned long flags; > }; > > +struct vhost_worker { > + struct task_struct *task; > + struct llist_head work_list; > + struct vhost_dev *dev; > + u64 kcov_handle; > +}; > + > /* Poll a file (eventfd or socket) */ > /* Note: there's nothing vhost specific about this structure. */ > struct vhost_poll { > @@ -148,8 +155,7 @@ struct vhost_dev { > struct vhost_virtqueue **vqs; > int nvqs; > struct eventfd_ctx *log_ctx; > - struct llist_head work_list; > - struct task_struct *worker; > + struct vhost_worker *worker; > struct vhost_iotlb *umem; > struct vhost_iotlb *iotlb; > spinlock_t iotlb_lock; > @@ -159,7 +165,6 @@ struct vhost_dev { > int iov_limit; > int weight; > int byte_weight; > - u64 kcov_handle; > bool use_worker; > int (*msg_handler)(struct vhost_dev *dev, > struct vhost_iotlb_msg *msg); > -- > 2.25.1 _______________________________________________ Virtualization mailing list [email protected] https://lists.linuxfoundation.org/mailman/listinfo/virtualization
