Commit 28f6288e authored by Xie Yongji's avatar Xie Yongji Committed by Michael S. Tsirkin
Browse files

vduse: Support set_vq_affinity callback 



Since virtio-vdpa bus driver already support interrupt
affinity spreading mechanism, let's implement the
set_vq_affinity callback to bring it to vduse device.
After we get the virtqueue's affinity, we can spread
IRQs between CPUs in the affinity mask, in a round-robin
manner, to run the irq callback.

Signed-off-by: default avatarXie Yongji <xieyongji@bytedance.com>
Message-Id: <20230323053043.35-6-xieyongji@bytedance.com>
Signed-off-by: default avatarMichael S. Tsirkin <mst@redhat.com>
Acked-by: default avatarJason Wang <jasowang@redhat.com>
parent 78885597

drivers/vdpa/vdpa_user/vduse_dev.c

+54 −7
Original line number Diff line number Diff line
@@ -41,6 +41,8 @@ 
#define VDUSE_IOVA_SIZE (128 * 1024 * 1024)

#define VDUSE_MSG_DEFAULT_TIMEOUT 30



#define IRQ_UNBOUND -1



struct vduse_virtqueue {

	u16 index;

	u16 num_max;
@@ -57,6 +59,8 @@ struct vduse_virtqueue { 
	struct vdpa_callback cb;

	struct work_struct inject;

	struct work_struct kick;

	int irq_effective_cpu;

	struct cpumask irq_affinity;

};



struct vduse_dev;
@@ -128,6 +132,7 @@ static struct class *vduse_class; 
static struct cdev vduse_ctrl_cdev;

static struct cdev vduse_cdev;

static struct workqueue_struct *vduse_irq_wq;

static struct workqueue_struct *vduse_irq_bound_wq;



static u32 allowed_device_id[] = {

	VIRTIO_ID_BLOCK,
@@ -708,6 +713,15 @@ static u32 vduse_vdpa_get_generation(struct vdpa_device *vdpa) 
	return dev->generation;

}



static int vduse_vdpa_set_vq_affinity(struct vdpa_device *vdpa, u16 idx,

				      const struct cpumask *cpu_mask)

{

	struct vduse_dev *dev = vdpa_to_vduse(vdpa);



	cpumask_copy(&dev->vqs[idx]->irq_affinity, cpu_mask);

	return 0;

}



static int vduse_vdpa_set_map(struct vdpa_device *vdpa,

				unsigned int asid,

				struct vhost_iotlb *iotlb)
@@ -758,6 +772,7 @@ static const struct vdpa_config_ops vduse_vdpa_config_ops = { 
	.get_config		= vduse_vdpa_get_config,

	.set_config		= vduse_vdpa_set_config,

	.get_generation		= vduse_vdpa_get_generation,

	.set_vq_affinity	= vduse_vdpa_set_vq_affinity,

	.reset			= vduse_vdpa_reset,

	.set_map		= vduse_vdpa_set_map,

	.free			= vduse_vdpa_free,
@@ -917,7 +932,8 @@ static void vduse_vq_irq_inject(struct work_struct *work) 
}



static int vduse_dev_queue_irq_work(struct vduse_dev *dev,

				    struct work_struct *irq_work)

				    struct work_struct *irq_work,

				    int irq_effective_cpu)

{

	int ret = -EINVAL;
@@ -926,7 +942,11 @@ static int vduse_dev_queue_irq_work(struct vduse_dev *dev, 
		goto unlock;



	ret = 0;

	if (irq_effective_cpu == IRQ_UNBOUND)

		queue_work(vduse_irq_wq, irq_work);

	else

		queue_work_on(irq_effective_cpu,

			      vduse_irq_bound_wq, irq_work);

unlock:

	up_read(&dev->rwsem);
@@ -1029,6 +1049,22 @@ static int vduse_dev_reg_umem(struct vduse_dev *dev, 
	return ret;

}



static void vduse_vq_update_effective_cpu(struct vduse_virtqueue *vq)

{

	int curr_cpu = vq->irq_effective_cpu;



	while (true) {

		curr_cpu = cpumask_next(curr_cpu, &vq->irq_affinity);

		if (cpu_online(curr_cpu))

			break;



		if (curr_cpu >= nr_cpu_ids)

			curr_cpu = IRQ_UNBOUND;

	}



	vq->irq_effective_cpu = curr_cpu;

}



static long vduse_dev_ioctl(struct file *file, unsigned int cmd,

			    unsigned long arg)

{
@@ -1111,7 +1147,7 @@ static long vduse_dev_ioctl(struct file *file, unsigned int cmd, 
		break;

	}

	case VDUSE_DEV_INJECT_CONFIG_IRQ:

		ret = vduse_dev_queue_irq_work(dev, &dev->inject);

		ret = vduse_dev_queue_irq_work(dev, &dev->inject, IRQ_UNBOUND);

		break;

	case VDUSE_VQ_SETUP: {

		struct vduse_vq_config config;
@@ -1198,7 +1234,10 @@ static long vduse_dev_ioctl(struct file *file, unsigned int cmd, 
			break;



		index = array_index_nospec(index, dev->vq_num);

		ret = vduse_dev_queue_irq_work(dev, &dev->vqs[index]->inject);



		vduse_vq_update_effective_cpu(dev->vqs[index]);

		ret = vduse_dev_queue_irq_work(dev, &dev->vqs[index]->inject,

					dev->vqs[index]->irq_effective_cpu);

		break;

	}

	case VDUSE_IOTLB_REG_UMEM: {
@@ -1367,10 +1406,12 @@ static int vduse_dev_init_vqs(struct vduse_dev *dev, u32 vq_align, u32 vq_num) 
			goto err;



		dev->vqs[i]->index = i;

		dev->vqs[i]->irq_effective_cpu = IRQ_UNBOUND;

		INIT_WORK(&dev->vqs[i]->inject, vduse_vq_irq_inject);

		INIT_WORK(&dev->vqs[i]->kick, vduse_vq_kick_work);

		spin_lock_init(&dev->vqs[i]->kick_lock);

		spin_lock_init(&dev->vqs[i]->irq_lock);

		cpumask_setall(&dev->vqs[i]->irq_affinity);

	}



	return 0;
@@ -1858,12 +1899,15 @@ static int vduse_init(void) 
	if (ret)

		goto err_cdev;



	ret = -ENOMEM;

	vduse_irq_wq = alloc_workqueue("vduse-irq",

				WQ_HIGHPRI | WQ_SYSFS | WQ_UNBOUND, 0);

	if (!vduse_irq_wq) {

		ret = -ENOMEM;

	if (!vduse_irq_wq)

		goto err_wq;

	}



	vduse_irq_bound_wq = alloc_workqueue("vduse-irq-bound", WQ_HIGHPRI, 0);

	if (!vduse_irq_bound_wq)

		goto err_bound_wq;



	ret = vduse_domain_init();

	if (ret)
@@ -1877,6 +1921,8 @@ static int vduse_init(void) 
err_mgmtdev:

	vduse_domain_exit();

err_domain:

	destroy_workqueue(vduse_irq_bound_wq);

err_bound_wq:

	destroy_workqueue(vduse_irq_wq);

err_wq:

	cdev_del(&vduse_cdev);
@@ -1896,6 +1942,7 @@ static void vduse_exit(void) 
{

	vduse_mgmtdev_exit();

	vduse_domain_exit();

	destroy_workqueue(vduse_irq_bound_wq);

	destroy_workqueue(vduse_irq_wq);

	cdev_del(&vduse_cdev);

	device_destroy(vduse_class, vduse_major);