* [PATCH] virtio: Introduce a new kick interface virtqueue_kick_try()
@ 2021-05-19 11:47 Xuan Zhuo
2021-05-19 12:44 ` Michael S. Tsirkin
2021-05-31 6:34 ` Jason Wang
0 siblings, 2 replies; 4+ messages in thread
From: Xuan Zhuo @ 2021-05-19 11:47 UTC (permalink / raw)
To: virtualization
Cc: Michael S. Tsirkin, Jason Wang, David S. Miller, Jakub Kicinski,
netdev
Unlike virtqueue_kick(), virtqueue_kick_try() returns true only when the
kick is successful. In virtio-net, we want to count the number of kicks.
So we need an interface that can perceive whether the kick is actually
executed.
Signed-off-by: Xuan Zhuo <xuanzhuo@linux.alibaba.com>
---
drivers/net/virtio_net.c | 8 ++++----
drivers/virtio/virtio_ring.c | 20 ++++++++++++++++++++
include/linux/virtio.h | 2 ++
3 files changed, 26 insertions(+), 4 deletions(-)
diff --git a/drivers/net/virtio_net.c b/drivers/net/virtio_net.c
index 9b6a4a875c55..167697030cb6 100644
--- a/drivers/net/virtio_net.c
+++ b/drivers/net/virtio_net.c
@@ -617,7 +617,7 @@ static int virtnet_xdp_xmit(struct net_device *dev,
ret = nxmit;
if (flags & XDP_XMIT_FLUSH) {
- if (virtqueue_kick_prepare(sq->vq) && virtqueue_notify(sq->vq))
+ if (virtqueue_kick_try(sq->vq))
kicks = 1;
}
out:
@@ -1325,7 +1325,7 @@ static bool try_fill_recv(struct virtnet_info *vi, struct receive_queue *rq,
if (err)
break;
} while (rq->vq->num_free);
- if (virtqueue_kick_prepare(rq->vq) && virtqueue_notify(rq->vq)) {
+ if (virtqueue_kick_try(rq->vq)) {
unsigned long flags;
flags = u64_stats_update_begin_irqsave(&rq->stats.syncp);
@@ -1533,7 +1533,7 @@ static int virtnet_poll(struct napi_struct *napi, int budget)
if (xdp_xmit & VIRTIO_XDP_TX) {
sq = virtnet_xdp_get_sq(vi);
- if (virtqueue_kick_prepare(sq->vq) && virtqueue_notify(sq->vq)) {
+ if (virtqueue_kick_try(sq->vq)) {
u64_stats_update_begin(&sq->stats.syncp);
sq->stats.kicks++;
u64_stats_update_end(&sq->stats.syncp);
@@ -1710,7 +1710,7 @@ static netdev_tx_t start_xmit(struct sk_buff *skb, struct net_device *dev)
}
if (kick || netif_xmit_stopped(txq)) {
- if (virtqueue_kick_prepare(sq->vq) && virtqueue_notify(sq->vq)) {
+ if (virtqueue_kick_try(sq->vq)) {
u64_stats_update_begin(&sq->stats.syncp);
sq->stats.kicks++;
u64_stats_update_end(&sq->stats.syncp);
diff --git a/drivers/virtio/virtio_ring.c b/drivers/virtio/virtio_ring.c
index 71e16b53e9c1..1462be756875 100644
--- a/drivers/virtio/virtio_ring.c
+++ b/drivers/virtio/virtio_ring.c
@@ -1874,6 +1874,26 @@ bool virtqueue_kick(struct virtqueue *vq)
}
EXPORT_SYMBOL_GPL(virtqueue_kick);
+/**
+ * virtqueue_kick_try - try update after add_buf
+ * @vq: the struct virtqueue
+ *
+ * After one or more virtqueue_add_* calls, invoke this to kick
+ * the other side.
+ *
+ * Caller must ensure we don't call this with other virtqueue
+ * operations at the same time (except where noted).
+ *
+ * Returns true if kick success, otherwise false.
+ */
+bool virtqueue_kick_try(struct virtqueue *vq)
+{
+ if (virtqueue_kick_prepare(vq) && virtqueue_notify(vq))
+ return true;
+ return false;
+}
+EXPORT_SYMBOL_GPL(virtqueue_kick_try);
+
/**
* virtqueue_get_buf - get the next used buffer
* @_vq: the struct virtqueue we're talking about.
diff --git a/include/linux/virtio.h b/include/linux/virtio.h
index b1894e0323fa..45cd6a0af24d 100644
--- a/include/linux/virtio.h
+++ b/include/linux/virtio.h
@@ -59,6 +59,8 @@ int virtqueue_add_sgs(struct virtqueue *vq,
bool virtqueue_kick(struct virtqueue *vq);
+bool virtqueue_kick_try(struct virtqueue *vq);
+
bool virtqueue_kick_prepare(struct virtqueue *vq);
bool virtqueue_notify(struct virtqueue *vq);
--
2.31.0
^ permalink raw reply related [flat|nested] 4+ messages in thread
* Re: [PATCH] virtio: Introduce a new kick interface virtqueue_kick_try()
2021-05-19 11:47 [PATCH] virtio: Introduce a new kick interface virtqueue_kick_try() Xuan Zhuo
@ 2021-05-19 12:44 ` Michael S. Tsirkin
2021-05-31 6:34 ` Jason Wang
1 sibling, 0 replies; 4+ messages in thread
From: Michael S. Tsirkin @ 2021-05-19 12:44 UTC (permalink / raw)
To: Xuan Zhuo
Cc: virtualization, Jason Wang, David S. Miller, Jakub Kicinski,
netdev
On Wed, May 19, 2021 at 07:47:57PM +0800, Xuan Zhuo wrote:
> Unlike virtqueue_kick(), virtqueue_kick_try() returns true only when the
> kick is successful. In virtio-net, we want to count the number of kicks.
> So we need an interface that can perceive whether the kick is actually
> executed.
>
> Signed-off-by: Xuan Zhuo <xuanzhuo@linux.alibaba.com>
> ---
> drivers/net/virtio_net.c | 8 ++++----
> drivers/virtio/virtio_ring.c | 20 ++++++++++++++++++++
> include/linux/virtio.h | 2 ++
> 3 files changed, 26 insertions(+), 4 deletions(-)
>
> diff --git a/drivers/net/virtio_net.c b/drivers/net/virtio_net.c
> index 9b6a4a875c55..167697030cb6 100644
> --- a/drivers/net/virtio_net.c
> +++ b/drivers/net/virtio_net.c
> @@ -617,7 +617,7 @@ static int virtnet_xdp_xmit(struct net_device *dev,
> ret = nxmit;
>
> if (flags & XDP_XMIT_FLUSH) {
> - if (virtqueue_kick_prepare(sq->vq) && virtqueue_notify(sq->vq))
> + if (virtqueue_kick_try(sq->vq))
> kicks = 1;
> }
> out:
> @@ -1325,7 +1325,7 @@ static bool try_fill_recv(struct virtnet_info *vi, struct receive_queue *rq,
> if (err)
> break;
> } while (rq->vq->num_free);
> - if (virtqueue_kick_prepare(rq->vq) && virtqueue_notify(rq->vq)) {
> + if (virtqueue_kick_try(rq->vq)) {
> unsigned long flags;
>
> flags = u64_stats_update_begin_irqsave(&rq->stats.syncp);
> @@ -1533,7 +1533,7 @@ static int virtnet_poll(struct napi_struct *napi, int budget)
>
> if (xdp_xmit & VIRTIO_XDP_TX) {
> sq = virtnet_xdp_get_sq(vi);
> - if (virtqueue_kick_prepare(sq->vq) && virtqueue_notify(sq->vq)) {
> + if (virtqueue_kick_try(sq->vq)) {
> u64_stats_update_begin(&sq->stats.syncp);
> sq->stats.kicks++;
> u64_stats_update_end(&sq->stats.syncp);
> @@ -1710,7 +1710,7 @@ static netdev_tx_t start_xmit(struct sk_buff *skb, struct net_device *dev)
> }
>
> if (kick || netif_xmit_stopped(txq)) {
> - if (virtqueue_kick_prepare(sq->vq) && virtqueue_notify(sq->vq)) {
> + if (virtqueue_kick_try(sq->vq)) {
> u64_stats_update_begin(&sq->stats.syncp);
> sq->stats.kicks++;
> u64_stats_update_end(&sq->stats.syncp);
> diff --git a/drivers/virtio/virtio_ring.c b/drivers/virtio/virtio_ring.c
> index 71e16b53e9c1..1462be756875 100644
> --- a/drivers/virtio/virtio_ring.c
> +++ b/drivers/virtio/virtio_ring.c
> @@ -1874,6 +1874,26 @@ bool virtqueue_kick(struct virtqueue *vq)
> }
> EXPORT_SYMBOL_GPL(virtqueue_kick);
>
> +/**
> + * virtqueue_kick_try - try update after add_buf
> + * @vq: the struct virtqueue
> + *
> + * After one or more virtqueue_add_* calls, invoke this to kick
> + * the other side.
> + *
> + * Caller must ensure we don't call this with other virtqueue
> + * operations at the same time (except where noted).
> + *
> + * Returns true if kick success, otherwise false.
so what is the difference between this and virtqueue_kick
which says
* Returns false if kick failed, otherwise true.
> + */
> +bool virtqueue_kick_try(struct virtqueue *vq)
> +{
> + if (virtqueue_kick_prepare(vq) && virtqueue_notify(vq))
> + return true;
> + return false;
> +}
> +EXPORT_SYMBOL_GPL(virtqueue_kick_try);
> +
> /**
> * virtqueue_get_buf - get the next used buffer
> * @_vq: the struct virtqueue we're talking about.
> diff --git a/include/linux/virtio.h b/include/linux/virtio.h
> index b1894e0323fa..45cd6a0af24d 100644
> --- a/include/linux/virtio.h
> +++ b/include/linux/virtio.h
> @@ -59,6 +59,8 @@ int virtqueue_add_sgs(struct virtqueue *vq,
>
> bool virtqueue_kick(struct virtqueue *vq);
>
> +bool virtqueue_kick_try(struct virtqueue *vq);
> +
> bool virtqueue_kick_prepare(struct virtqueue *vq);
>
> bool virtqueue_notify(struct virtqueue *vq);
> --
> 2.31.0
^ permalink raw reply [flat|nested] 4+ messages in thread
* Re: [PATCH] virtio: Introduce a new kick interface virtqueue_kick_try()
2021-05-19 11:47 [PATCH] virtio: Introduce a new kick interface virtqueue_kick_try() Xuan Zhuo
2021-05-19 12:44 ` Michael S. Tsirkin
@ 2021-05-31 6:34 ` Jason Wang
[not found] ` <1634631199.0198228-1-xuanzhuo@linux.alibaba.com>
1 sibling, 1 reply; 4+ messages in thread
From: Jason Wang @ 2021-05-31 6:34 UTC (permalink / raw)
To: Xuan Zhuo, virtualization
Cc: Michael S. Tsirkin, David S. Miller, Jakub Kicinski, netdev
在 2021/5/19 下午7:47, Xuan Zhuo 写道:
> Unlike virtqueue_kick(), virtqueue_kick_try() returns true only when the
> kick is successful. In virtio-net, we want to count the number of kicks.
> So we need an interface that can perceive whether the kick is actually
> executed.
>
> Signed-off-by: Xuan Zhuo <xuanzhuo@linux.alibaba.com>
Acked-by: Jason Wang <jasowang@redhat.com>
Thanks
> ---
> drivers/net/virtio_net.c | 8 ++++----
> drivers/virtio/virtio_ring.c | 20 ++++++++++++++++++++
> include/linux/virtio.h | 2 ++
> 3 files changed, 26 insertions(+), 4 deletions(-)
>
> diff --git a/drivers/net/virtio_net.c b/drivers/net/virtio_net.c
> index 9b6a4a875c55..167697030cb6 100644
> --- a/drivers/net/virtio_net.c
> +++ b/drivers/net/virtio_net.c
> @@ -617,7 +617,7 @@ static int virtnet_xdp_xmit(struct net_device *dev,
> ret = nxmit;
>
> if (flags & XDP_XMIT_FLUSH) {
> - if (virtqueue_kick_prepare(sq->vq) && virtqueue_notify(sq->vq))
> + if (virtqueue_kick_try(sq->vq))
> kicks = 1;
> }
> out:
> @@ -1325,7 +1325,7 @@ static bool try_fill_recv(struct virtnet_info *vi, struct receive_queue *rq,
> if (err)
> break;
> } while (rq->vq->num_free);
> - if (virtqueue_kick_prepare(rq->vq) && virtqueue_notify(rq->vq)) {
> + if (virtqueue_kick_try(rq->vq)) {
> unsigned long flags;
>
> flags = u64_stats_update_begin_irqsave(&rq->stats.syncp);
> @@ -1533,7 +1533,7 @@ static int virtnet_poll(struct napi_struct *napi, int budget)
>
> if (xdp_xmit & VIRTIO_XDP_TX) {
> sq = virtnet_xdp_get_sq(vi);
> - if (virtqueue_kick_prepare(sq->vq) && virtqueue_notify(sq->vq)) {
> + if (virtqueue_kick_try(sq->vq)) {
> u64_stats_update_begin(&sq->stats.syncp);
> sq->stats.kicks++;
> u64_stats_update_end(&sq->stats.syncp);
> @@ -1710,7 +1710,7 @@ static netdev_tx_t start_xmit(struct sk_buff *skb, struct net_device *dev)
> }
>
> if (kick || netif_xmit_stopped(txq)) {
> - if (virtqueue_kick_prepare(sq->vq) && virtqueue_notify(sq->vq)) {
> + if (virtqueue_kick_try(sq->vq)) {
> u64_stats_update_begin(&sq->stats.syncp);
> sq->stats.kicks++;
> u64_stats_update_end(&sq->stats.syncp);
> diff --git a/drivers/virtio/virtio_ring.c b/drivers/virtio/virtio_ring.c
> index 71e16b53e9c1..1462be756875 100644
> --- a/drivers/virtio/virtio_ring.c
> +++ b/drivers/virtio/virtio_ring.c
> @@ -1874,6 +1874,26 @@ bool virtqueue_kick(struct virtqueue *vq)
> }
> EXPORT_SYMBOL_GPL(virtqueue_kick);
>
> +/**
> + * virtqueue_kick_try - try update after add_buf
> + * @vq: the struct virtqueue
> + *
> + * After one or more virtqueue_add_* calls, invoke this to kick
> + * the other side.
> + *
> + * Caller must ensure we don't call this with other virtqueue
> + * operations at the same time (except where noted).
> + *
> + * Returns true if kick success, otherwise false.
> + */
> +bool virtqueue_kick_try(struct virtqueue *vq)
> +{
> + if (virtqueue_kick_prepare(vq) && virtqueue_notify(vq))
> + return true;
> + return false;
> +}
> +EXPORT_SYMBOL_GPL(virtqueue_kick_try);
> +
> /**
> * virtqueue_get_buf - get the next used buffer
> * @_vq: the struct virtqueue we're talking about.
> diff --git a/include/linux/virtio.h b/include/linux/virtio.h
> index b1894e0323fa..45cd6a0af24d 100644
> --- a/include/linux/virtio.h
> +++ b/include/linux/virtio.h
> @@ -59,6 +59,8 @@ int virtqueue_add_sgs(struct virtqueue *vq,
>
> bool virtqueue_kick(struct virtqueue *vq);
>
> +bool virtqueue_kick_try(struct virtqueue *vq);
> +
> bool virtqueue_kick_prepare(struct virtqueue *vq);
>
> bool virtqueue_notify(struct virtqueue *vq);
^ permalink raw reply [flat|nested] 4+ messages in thread
* Re: [PATCH] virtio: Introduce a new kick interface virtqueue_kick_try()
[not found] ` <1634631199.0198228-1-xuanzhuo@linux.alibaba.com>
@ 2021-10-19 10:37 ` Michael S. Tsirkin
0 siblings, 0 replies; 4+ messages in thread
From: Michael S. Tsirkin @ 2021-10-19 10:37 UTC (permalink / raw)
To: Xuan Zhuo
Cc: Jason Wang, David S. Miller, Jakub Kicinski, netdev,
virtualization
On Tue, Oct 19, 2021 at 04:13:19PM +0800, Xuan Zhuo wrote:
> On Mon, 31 May 2021 14:34:16 +0800, Jason Wang <jasowang@redhat.com> wrote:
> >
> > ÔÚ 2021/5/19 ÏÂÎç7:47, Xuan Zhuo дµÀ:
> > > Unlike virtqueue_kick(), virtqueue_kick_try() returns true only when the
> > > kick is successful. In virtio-net, we want to count the number of kicks.
> > > So we need an interface that can perceive whether the kick is actually
> > > executed.
> > >
> > > Signed-off-by: Xuan Zhuo <xuanzhuo@linux.alibaba.com>
> >
> >
> > Acked-by: Jason Wang <jasowang@redhat.com>
>
> Hi, this patch seems to have not been merged, is there something wrong with me?
>
> Thanks.
The commit log does not make it clear, but this is just
code refactoring. Pls make it clearer in the log.
Also, if we add a new API like this as a cleanup,
it needs to be documented much better.
> >
> > Thanks
> >
> >
> > > ---
> > > drivers/net/virtio_net.c | 8 ++++----
> > > drivers/virtio/virtio_ring.c | 20 ++++++++++++++++++++
> > > include/linux/virtio.h | 2 ++
> > > 3 files changed, 26 insertions(+), 4 deletions(-)
> > >
> > > diff --git a/drivers/net/virtio_net.c b/drivers/net/virtio_net.c
> > > index 9b6a4a875c55..167697030cb6 100644
> > > --- a/drivers/net/virtio_net.c
> > > +++ b/drivers/net/virtio_net.c
> > > @@ -617,7 +617,7 @@ static int virtnet_xdp_xmit(struct net_device *dev,
> > > ret = nxmit;
> > >
> > > if (flags & XDP_XMIT_FLUSH) {
> > > - if (virtqueue_kick_prepare(sq->vq) && virtqueue_notify(sq->vq))
> > > + if (virtqueue_kick_try(sq->vq))
> > > kicks = 1;
> > > }
> > > out:
> > > @@ -1325,7 +1325,7 @@ static bool try_fill_recv(struct virtnet_info *vi, struct receive_queue *rq,
> > > if (err)
> > > break;
> > > } while (rq->vq->num_free);
> > > - if (virtqueue_kick_prepare(rq->vq) && virtqueue_notify(rq->vq)) {
> > > + if (virtqueue_kick_try(rq->vq)) {
> > > unsigned long flags;
> > >
> > > flags = u64_stats_update_begin_irqsave(&rq->stats.syncp);
> > > @@ -1533,7 +1533,7 @@ static int virtnet_poll(struct napi_struct *napi, int budget)
> > >
> > > if (xdp_xmit & VIRTIO_XDP_TX) {
> > > sq = virtnet_xdp_get_sq(vi);
> > > - if (virtqueue_kick_prepare(sq->vq) && virtqueue_notify(sq->vq)) {
> > > + if (virtqueue_kick_try(sq->vq)) {
> > > u64_stats_update_begin(&sq->stats.syncp);
> > > sq->stats.kicks++;
> > > u64_stats_update_end(&sq->stats.syncp);
> > > @@ -1710,7 +1710,7 @@ static netdev_tx_t start_xmit(struct sk_buff *skb, struct net_device *dev)
> > > }
> > >
> > > if (kick || netif_xmit_stopped(txq)) {
> > > - if (virtqueue_kick_prepare(sq->vq) && virtqueue_notify(sq->vq)) {
> > > + if (virtqueue_kick_try(sq->vq)) {
> > > u64_stats_update_begin(&sq->stats.syncp);
> > > sq->stats.kicks++;
> > > u64_stats_update_end(&sq->stats.syncp);
> > > diff --git a/drivers/virtio/virtio_ring.c b/drivers/virtio/virtio_ring.c
> > > index 71e16b53e9c1..1462be756875 100644
> > > --- a/drivers/virtio/virtio_ring.c
> > > +++ b/drivers/virtio/virtio_ring.c
> > > @@ -1874,6 +1874,26 @@ bool virtqueue_kick(struct virtqueue *vq)
> > > }
> > > EXPORT_SYMBOL_GPL(virtqueue_kick);
> > >
> > > +/**
> > > + * virtqueue_kick_try - try update after add_buf
> > > + * @vq: the struct virtqueue
> > > + *
> > > + * After one or more virtqueue_add_* calls, invoke this to kick
> > > + * the other side.
> > > + *
> > > + * Caller must ensure we don't call this with other virtqueue
> > > + * operations at the same time (except where noted).
> > > + *
> > > + * Returns true if kick success, otherwise false.
on a successful kick?
> > > + */
I don't really understand what this is doing, the comment
doesn't seem to explain. Try implies it might fail to update.
virtqueue_kick seems to be documented the same:
* Returns false if kick failed, otherwise true.
> > > +bool virtqueue_kick_try(struct virtqueue *vq)
> > > +{
> > > + if (virtqueue_kick_prepare(vq) && virtqueue_notify(vq))
> > > + return true;
> > > + return false;
> > > +}
> > > +EXPORT_SYMBOL_GPL(virtqueue_kick_try);
> > > +
> > > /**
> > > * virtqueue_get_buf - get the next used buffer
> > > * @_vq: the struct virtqueue we're talking about.
> > > diff --git a/include/linux/virtio.h b/include/linux/virtio.h
> > > index b1894e0323fa..45cd6a0af24d 100644
> > > --- a/include/linux/virtio.h
> > > +++ b/include/linux/virtio.h
> > > @@ -59,6 +59,8 @@ int virtqueue_add_sgs(struct virtqueue *vq,
> > >
> > > bool virtqueue_kick(struct virtqueue *vq);
> > >
> > > +bool virtqueue_kick_try(struct virtqueue *vq);
> > > +
> > > bool virtqueue_kick_prepare(struct virtqueue *vq);
> > >
> > > bool virtqueue_notify(struct virtqueue *vq);
> >
^ permalink raw reply [flat|nested] 4+ messages in thread
end of thread, other threads:[~2021-10-19 10:37 UTC | newest]
Thread overview: 4+ messages (download: mbox.gz follow: Atom feed
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2021-05-19 11:47 [PATCH] virtio: Introduce a new kick interface virtqueue_kick_try() Xuan Zhuo
2021-05-19 12:44 ` Michael S. Tsirkin
2021-05-31 6:34 ` Jason Wang
[not found] ` <1634631199.0198228-1-xuanzhuo@linux.alibaba.com>
2021-10-19 10:37 ` Michael S. Tsirkin
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