On 2020/7/12 下午10:49, Zhu Lingshan wrote:
This patch introduce a set of functions for setup/unsetup
and update irq offloading respectively by register/unregister
and re-register the irq_bypass_producer.
Signed-off-by: Zhu Lingshan <lingshan.zhu@xxxxxxxxx>
---
drivers/vhost/vdpa.c | 69 ++++++++++++++++++++++++++++++++++++++++++++++++++++
1 file changed, 69 insertions(+)
diff --git a/drivers/vhost/vdpa.c b/drivers/vhost/vdpa.c
index 2fcc422..92683e4 100644
--- a/drivers/vhost/vdpa.c
+++ b/drivers/vhost/vdpa.c
@@ -115,6 +115,63 @@ static irqreturn_t vhost_vdpa_config_cb(void *private)
return IRQ_HANDLED;
}
+static void vhost_vdpa_setup_vq_irq(struct vdpa_device *dev, int qid, int irq)
+{
+ struct vhost_vdpa *v = vdpa_get_drvdata(dev);
+ struct vhost_virtqueue *vq = &v->vqs[qid];
+ int ret;
+
+ vq_err(vq, "setup irq bypass for vq %d with irq = %d\n", qid, irq);
+ spin_lock(&vq->call_ctx.ctx_lock);
+ if (!vq->call_ctx.ctx)
+ return;
+
+ vq->call_ctx.producer.token = vq->call_ctx.ctx;
+ vq->call_ctx.producer.irq = irq;
+ ret = irq_bypass_register_producer(&vq->call_ctx.producer);
+ spin_unlock(&vq->call_ctx.ctx_lock);
+
+ if (unlikely(ret))
+ vq_err(vq,
+ "irq bypass producer (token %p registration fails: %d\n",
+ vq->call_ctx.producer.token, ret);
Not sure this deserves a vq_err(), irq will be relayed through eventfd
if irq bypass manager can't work.
+}
+
+static void vhost_vdpa_unsetup_vq_irq(struct vdpa_device *dev, int qid)
+{
+ struct vhost_vdpa *v = vdpa_get_drvdata(dev);
+ struct vhost_virtqueue *vq = &v->vqs[qid];
+
+ spin_lock(&vq->call_ctx.ctx_lock);
+ irq_bypass_unregister_producer(&vq->call_ctx.producer);
+ spin_unlock(&vq->call_ctx.ctx_lock);
+
+ vq_err(vq, "unsetup irq bypass for vq %d\n", qid);
Why call vq_err() here?
+}
+
+static void vhost_vdpa_update_vq_irq(struct vhost_virtqueue *vq)
+{
+ struct eventfd_ctx *ctx;
+ void *token;
+
+ spin_lock(&vq->call_ctx.ctx_lock);
+ ctx = vq->call_ctx.ctx;
+ token = vq->call_ctx.producer.token;
+ if (ctx == token)
+ return;
Need do unlock here.
+
+ if (!ctx && token)
+ irq_bypass_unregister_producer(&vq->call_ctx.producer);
+
+ if (ctx && ctx != token) {
+ irq_bypass_unregister_producer(&vq->call_ctx.producer);
+ vq->call_ctx.producer.token = ctx;
+ irq_bypass_register_producer(&vq->call_ctx.producer);
+ }
+
+ spin_unlock(&vq->call_ctx.ctx_lock);
This should be rare so I'd use simple codes just do unregister and register.
+}
+
static void vhost_vdpa_reset(struct vhost_vdpa *v)
{
struct vdpa_device *vdpa = v->vdpa;
@@ -332,6 +389,7 @@ static long vhost_vdpa_set_config_call(struct vhost_vdpa *v, u32 __user *argp)
return 0;
}
+
Unnecessary change.
static long vhost_vdpa_vring_ioctl(struct vhost_vdpa *v, unsigned int cmd,
void __user *argp)
{
@@ -390,6 +448,16 @@ static long vhost_vdpa_vring_ioctl(struct vhost_vdpa *v, unsigned int cmd,
cb.private = NULL;
}
ops->set_vq_cb(vdpa, idx, &cb);
+#ifdef CONFIG_HAVE_KVM_IRQ_BYPASS
+ /*
+ * if it has a non-zero irq, means there is a
+ * previsouly registered irq_bypass_producer,
+ * we should update it when ctx (its token)
+ * changes.
+ */
+ if (vq->call_ctx.producer.irq)
+ vhost_vdpa_update_vq_irq(vq);
+#endif
break;
case VHOST_SET_VRING_NUM:
@@ -741,6 +809,7 @@ static int vhost_vdpa_open(struct inode *inode, struct file *filep)
vqs[i] = &v->vqs[i];
vqs[i]->handle_kick = handle_vq_kick;
}
+
Unnecessary change.
Thanks
vhost_dev_init(dev, vqs, nvqs, 0, 0, 0, false,
vhost_vdpa_process_iotlb_msg);
