From: Mike Christie <michael.chris...@oracle.com> The next patch allows userspace to create multiple workers per device, so this patch replaces the vhost_worker pointer with an xarray so we can store mupltiple workers and look them up.
Signed-off-by: Mike Christie <michael.chris...@oracle.com> Message-Id: <20230626232307.97930-15-michael.chris...@oracle.com> Signed-off-by: Michael S. Tsirkin <m...@redhat.com> -------- Also rework vhost_work_queue() to use any worker. We are not going to add patches that rework all its usages. (cherry picked from ms commit 1cdaafa1b8b4) https://virtuozzo.atlassian.net/browse/PSBM-152375 Signed-off-by: Andrey Zhadchenko <andrey.zhadche...@virtuozzo.com> --- drivers/vhost/vhost.c | 66 +++++++++++++++++++++++++++++++++++-------- drivers/vhost/vhost.h | 3 +- 2 files changed, 56 insertions(+), 13 deletions(-) diff --git a/drivers/vhost/vhost.c b/drivers/vhost/vhost.c index c48df967d625..719b1784a32b 100644 --- a/drivers/vhost/vhost.c +++ b/drivers/vhost/vhost.c @@ -257,7 +257,14 @@ static bool vhost_worker_queue(struct vhost_worker *worker, bool vhost_work_queue(struct vhost_dev *dev, struct vhost_work *work) { - return vhost_worker_queue(dev->worker, work); + XA_STATE(xas, &dev->worker_xa, 0); + struct vhost_worker *worker; + + worker = xas_find(&xas, UINT_MAX); + if (!worker) + return false; + + return vhost_worker_queue(worker, work); } EXPORT_SYMBOL_GPL(vhost_work_queue); @@ -286,7 +293,11 @@ EXPORT_SYMBOL_GPL(vhost_vq_flush); void vhost_dev_flush(struct vhost_dev *dev) { - vhost_worker_flush(dev->worker); + struct vhost_worker *worker; + unsigned long i; + + xa_for_each(&dev->worker_xa, i, worker) + vhost_worker_flush(worker); } EXPORT_SYMBOL_GPL(vhost_dev_flush); @@ -501,7 +512,6 @@ void vhost_dev_init(struct vhost_dev *dev, dev->umem = NULL; dev->iotlb = NULL; dev->mm = NULL; - dev->worker = NULL; dev->iov_limit = iov_limit; dev->weight = weight; dev->byte_weight = byte_weight; @@ -511,6 +521,7 @@ void vhost_dev_init(struct vhost_dev *dev, INIT_LIST_HEAD(&dev->read_list); INIT_LIST_HEAD(&dev->pending_list); spin_lock_init(&dev->iotlb_lock); + xa_init_flags(&dev->worker_xa, XA_FLAGS_ALLOC); for (i = 0; i < dev->nvqs; ++i) { @@ -598,37 +609,61 @@ static void vhost_detach_mm(struct vhost_dev *dev) dev->mm = NULL; } -static void vhost_worker_free(struct vhost_dev *dev) +static void vhost_worker_destroy(struct vhost_dev *dev, + struct vhost_worker *worker) { - struct vhost_worker *worker = dev->worker; - if (!worker) return; - dev->worker = NULL; WARN_ON(!llist_empty(&worker->work_list)); + xa_erase(&dev->worker_xa, worker->id); kthread_stop(worker->task); kfree(worker); } +static void vhost_workers_free(struct vhost_dev *dev) +{ + struct vhost_worker *worker; + unsigned long i; + + if (!dev->use_worker) + return; + + for (i = 0; i < dev->nvqs; i++) + dev->vqs[i]->worker = NULL; + /* + * Free the default worker we created and cleanup workers userspace + * created but couldn't clean up (it forgot or crashed). + */ + xa_for_each(&dev->worker_xa, i, worker) + vhost_worker_destroy(dev, worker); + xa_destroy(&dev->worker_xa); +} + static struct vhost_worker *vhost_worker_create(struct vhost_dev *dev) { struct vhost_worker *worker; struct task_struct *task; int ret; + u32 id; worker = kzalloc(sizeof(*worker), GFP_KERNEL_ACCOUNT); if (!worker) return NULL; - 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 = xa_alloc(&dev->worker_xa, &id, worker, xa_limit_32b, GFP_KERNEL); + if (ret < 0) goto free_worker; + worker->id = id; + + task = kthread_create(vhost_worker, worker, "vhost-%d-%d", + current->pid, worker->id); + if (IS_ERR(task)) + goto erase_xa; worker->task = task; wake_up_process(task); /* avoid contributing to loadavg */ @@ -641,9 +676,10 @@ static struct vhost_worker *vhost_worker_create(struct vhost_dev *dev) stop_worker: kthread_stop(worker->task); +erase_xa: + xa_erase(&dev->worker_xa, id); free_worker: kfree(worker); - dev->worker = NULL; return NULL; } @@ -699,6 +735,12 @@ long vhost_dev_set_owner(struct vhost_dev *dev) goto err_worker; } + /* + * vsock can already try to queue so make sure the worker + * is setup before vhost_vq_work_queue sees vq->worker is set. + */ + smp_wmb(); + for (i = 0; i < dev->nvqs; i++) dev->vqs[i]->worker = worker; } @@ -799,7 +841,7 @@ void vhost_dev_cleanup(struct vhost_dev *dev) dev->iotlb = NULL; vhost_clear_msg(dev); wake_up_interruptible_poll(&dev->wait, EPOLLIN | EPOLLRDNORM); - vhost_worker_free(dev); + vhost_workers_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 6155cf5033c7..b40c041f2edb 100644 --- a/drivers/vhost/vhost.h +++ b/drivers/vhost/vhost.h @@ -30,6 +30,7 @@ struct vhost_worker { struct llist_head work_list; struct vhost_dev *dev; u64 kcov_handle; + u32 id; }; /* Poll a file (eventfd or socket) */ @@ -160,7 +161,6 @@ struct vhost_dev { struct vhost_virtqueue **vqs; int nvqs; struct eventfd_ctx *log_ctx; - struct vhost_worker *worker; struct vhost_iotlb *umem; struct vhost_iotlb *iotlb; spinlock_t iotlb_lock; @@ -170,6 +170,7 @@ struct vhost_dev { int iov_limit; int weight; int byte_weight; + struct xarray worker_xa; bool use_worker; int (*msg_handler)(struct vhost_dev *dev, u32 asid, struct vhost_iotlb_msg *msg); -- 2.39.3 _______________________________________________ Devel mailing list Devel@openvz.org https://lists.openvz.org/mailman/listinfo/devel
