| Message ID | 20210519114757.6143-1-xuanzhuo@linux.alibaba.com (mailing list archive) |
|---|---|
| State | Changes Requested |
| Delegated to: | Netdev Maintainers |
| Headers | show |
| Series | virtio: Introduce a new kick interface virtqueue_kick_try() | expand |
| Context | Check | Description |
|---|---|---|
| netdev/tree_selection | success | Not a local patch |
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
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);
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); > >
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);
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(-)