On 2020/7/15 下午4:56, Zhu, Lingshan wrote:
On 7/15/2020 4:51 PM, Jason Wang wrote:
On 2020/7/13 下午5:47, Zhu, Lingshan wrote:
On 7/13/2020 4:22 PM, Jason Wang wrote:
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.
OK, I see vq_err() will eventfd_signal err_ctx than just print a
message, will remove all vq_err().
+}
+
+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.
sure!
+
+ 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.
do you mean remove "if (ctx && ctx != token)"? I think this could be
useful, we should only update it when ctx!=NULL and ctx!= existing
token.
I meant something like:
unregister();
vq->call_ctx.producer.token = ctx;
register();
This is what we are doing now, or I must missed somethig:
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);
}
It just unregister and register.
I meant there's probably no need for the check and another check and
unregister before. The whole function is as simple as I suggested above.
Thanks
Thanks,
BR
Zhu Lingshan
