From e82b9b0727ff6d665fff2d326162b460dded554d Mon Sep 17 00:00:00 2001 From: Jason Wang Date: Fri, 17 May 2019 00:29:49 -0400 Subject: vhost: introduce vhost_exceeds_weight() We used to have vhost_exceeds_weight() for vhost-net to: - prevent vhost kthread from hogging the cpu - balance the time spent between TX and RX This function could be useful for vsock and scsi as well. So move it to vhost.c. Device must specify a weight which counts the number of requests, or it can also specific a byte_weight which counts the number of bytes that has been processed. Signed-off-by: Jason Wang Reviewed-by: Stefan Hajnoczi Signed-off-by: Michael S. Tsirkin --- drivers/vhost/vhost.c | 20 +++++++++++++++++++- 1 file changed, 19 insertions(+), 1 deletion(-) (limited to 'drivers/vhost/vhost.c') diff --git a/drivers/vhost/vhost.c b/drivers/vhost/vhost.c index 1e3ed41ae1f3..3f3eac4bcc58 100644 --- a/drivers/vhost/vhost.c +++ b/drivers/vhost/vhost.c @@ -413,8 +413,24 @@ static void vhost_dev_free_iovecs(struct vhost_dev *dev) vhost_vq_free_iovecs(dev->vqs[i]); } +bool vhost_exceeds_weight(struct vhost_virtqueue *vq, + int pkts, int total_len) +{ + struct vhost_dev *dev = vq->dev; + + if ((dev->byte_weight && total_len >= dev->byte_weight) || + pkts >= dev->weight) { + vhost_poll_queue(&vq->poll); + return true; + } + + return false; +} +EXPORT_SYMBOL_GPL(vhost_exceeds_weight); + void vhost_dev_init(struct vhost_dev *dev, - struct vhost_virtqueue **vqs, int nvqs, int iov_limit) + struct vhost_virtqueue **vqs, int nvqs, + int iov_limit, int weight, int byte_weight) { struct vhost_virtqueue *vq; int i; @@ -428,6 +444,8 @@ void vhost_dev_init(struct vhost_dev *dev, dev->mm = NULL; dev->worker = NULL; dev->iov_limit = iov_limit; + dev->weight = weight; + dev->byte_weight = byte_weight; init_llist_head(&dev->work_list); init_waitqueue_head(&dev->wait); INIT_LIST_HEAD(&dev->read_list); -- cgit v1.2.3