Re: [PATCH 4/6] virtio_net: allow specifying context for rx

2017-03-30 Thread Cornelia Huck 
On Thu, 30 Mar 2017 17:31:37 +0300
"Michael S. Tsirkin"  wrote:

> On Thu, Mar 30, 2017 at 09:26:51AM +0200, Cornelia Huck wrote:
> > On Wed, 29 Mar 2017 23:48:54 +0300
> > "Michael S. Tsirkin"  wrote:
> > 
> > > With mergeable buffers we never use s/g for rx,
> > > so allow specifying context in that case.
> > > 
> > > Signed-off-by: Michael S. Tsirkin 
> > > ---
> > >  drivers/net/virtio_net.c | 15 ++-
> > >  1 file changed, 14 insertions(+), 1 deletion(-)
> > > 
> > > diff --git a/drivers/net/virtio_net.c b/drivers/net/virtio_net.c
> > > index 6802169..340f737 100644
> > > --- a/drivers/net/virtio_net.c
> > > +++ b/drivers/net/virtio_net.c
> > > @@ -2044,6 +2044,7 @@ static int virtnet_find_vqs(struct virtnet_info *vi)
> > >   int ret = -ENOMEM;
> > >   int i, total_vqs;
> > >   const char **names;
> > > + const bool *ctx;
> > >  
> > >   /* We expect 1 RX virtqueue followed by 1 TX virtqueue, followed by
> > >* possible N-1 RX/TX queue pairs used in multiqueue mode, followed by
> > > @@ -2062,6 +2063,13 @@ static int virtnet_find_vqs(struct virtnet_info 
> > > *vi)
> > >   names = kmalloc(total_vqs * sizeof(*names), GFP_KERNEL);
> > >   if (!names)
> > >   goto err_names;
> > > + if (vi->mergeable_rx_bufs) {
> > > + ctx = kzalloc(total_vqs * sizeof(*ctx), GFP_KERNEL);
> > > + if (!ctx)
> > > + goto err_ctx;
> > > + } else {
> > > + ctx = NULL;
> > > + }
> > >  
> > >   /* Parameters for control virtqueue, if any */
> > >   if (vi->has_cvq) {
> > > @@ -2077,9 +2085,12 @@ static int virtnet_find_vqs(struct virtnet_info 
> > > *vi)
> > >   sprintf(vi->sq[i].name, "output.%d", i);
> > >   names[rxq2vq(i)] = vi->rq[i].name;
> > >   names[txq2vq(i)] = vi->sq[i].name;
> > > + if (ctx)
> > > + ctx[rxq2vq(i)] = true;
> > >   }
> > >  
> > > - ret = virtio_find_vqs(vi->vdev, total_vqs, vqs, callbacks, names, NULL);
> > > + ret = vi->vdev->config->find_vqs(vi->vdev, total_vqs, vqs, callbacks,
> > > +  names, ctx, NULL);
> > 
> > virtio_find_vqs_ctx()? (Needs to be exported, obviously.)
> 
> I guess I can do that but there's a single user ATM.
> Do you think it's worth doing right now, or wait until
> it gets more users?

Given that you introduce it in patch 2, I'd just make it an exported
function from the start. (It also looks nicer IMO.)

Re: [PATCH 4/6] virtio_net: allow specifying context for rx

2017-03-30 Thread Michael S. Tsirkin 
On Thu, Mar 30, 2017 at 09:26:51AM +0200, Cornelia Huck wrote:
> On Wed, 29 Mar 2017 23:48:54 +0300
> "Michael S. Tsirkin"  wrote:
> 
> > With mergeable buffers we never use s/g for rx,
> > so allow specifying context in that case.
> > 
> > Signed-off-by: Michael S. Tsirkin 
> > ---
> >  drivers/net/virtio_net.c | 15 ++-
> >  1 file changed, 14 insertions(+), 1 deletion(-)
> > 
> > diff --git a/drivers/net/virtio_net.c b/drivers/net/virtio_net.c
> > index 6802169..340f737 100644
> > --- a/drivers/net/virtio_net.c
> > +++ b/drivers/net/virtio_net.c
> > @@ -2044,6 +2044,7 @@ static int virtnet_find_vqs(struct virtnet_info *vi)
> > int ret = -ENOMEM;
> > int i, total_vqs;
> > const char **names;
> > +   const bool *ctx;
> >  
> > /* We expect 1 RX virtqueue followed by 1 TX virtqueue, followed by
> >  * possible N-1 RX/TX queue pairs used in multiqueue mode, followed by
> > @@ -2062,6 +2063,13 @@ static int virtnet_find_vqs(struct virtnet_info *vi)
> > names = kmalloc(total_vqs * sizeof(*names), GFP_KERNEL);
> > if (!names)
> > goto err_names;
> > +   if (vi->mergeable_rx_bufs) {
> > +   ctx = kzalloc(total_vqs * sizeof(*ctx), GFP_KERNEL);
> > +   if (!ctx)
> > +   goto err_ctx;
> > +   } else {
> > +   ctx = NULL;
> > +   }
> >  
> > /* Parameters for control virtqueue, if any */
> > if (vi->has_cvq) {
> > @@ -2077,9 +2085,12 @@ static int virtnet_find_vqs(struct virtnet_info *vi)
> > sprintf(vi->sq[i].name, "output.%d", i);
> > names[rxq2vq(i)] = vi->rq[i].name;
> > names[txq2vq(i)] = vi->sq[i].name;
> > +   if (ctx)
> > +   ctx[rxq2vq(i)] = true;
> > }
> >  
> > -   ret = virtio_find_vqs(vi->vdev, total_vqs, vqs, callbacks, names, NULL);
> > +   ret = vi->vdev->config->find_vqs(vi->vdev, total_vqs, vqs, callbacks,
> > +names, ctx, NULL);
> 
> virtio_find_vqs_ctx()? (Needs to be exported, obviously.)

I guess I can do that but there's a single user ATM.
Do you think it's worth doing right now, or wait until
it gets more users?


> > if (ret)
> > goto err_find;
> >  
> > @@ -2101,6 +2112,8 @@ static int virtnet_find_vqs(struct virtnet_info *vi)
> > return 0;
> >  
> >  err_find:
> > +   kfree(ctx);
> > +err_ctx:
> > kfree(names);
> >  err_names:
> > kfree(callbacks);

Re: [PATCH 4/6] virtio_net: allow specifying context for rx

2017-03-30 Thread Cornelia Huck 
On Wed, 29 Mar 2017 23:48:54 +0300
"Michael S. Tsirkin"  wrote:

> With mergeable buffers we never use s/g for rx,
> so allow specifying context in that case.
> 
> Signed-off-by: Michael S. Tsirkin 
> ---
>  drivers/net/virtio_net.c | 15 ++-
>  1 file changed, 14 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/net/virtio_net.c b/drivers/net/virtio_net.c
> index 6802169..340f737 100644
> --- a/drivers/net/virtio_net.c
> +++ b/drivers/net/virtio_net.c
> @@ -2044,6 +2044,7 @@ static int virtnet_find_vqs(struct virtnet_info *vi)
>   int ret = -ENOMEM;
>   int i, total_vqs;
>   const char **names;
> + const bool *ctx;
>  
>   /* We expect 1 RX virtqueue followed by 1 TX virtqueue, followed by
>* possible N-1 RX/TX queue pairs used in multiqueue mode, followed by
> @@ -2062,6 +2063,13 @@ static int virtnet_find_vqs(struct virtnet_info *vi)
>   names = kmalloc(total_vqs * sizeof(*names), GFP_KERNEL);
>   if (!names)
>   goto err_names;
> + if (vi->mergeable_rx_bufs) {
> + ctx = kzalloc(total_vqs * sizeof(*ctx), GFP_KERNEL);
> + if (!ctx)
> + goto err_ctx;
> + } else {
> + ctx = NULL;
> + }
>  
>   /* Parameters for control virtqueue, if any */
>   if (vi->has_cvq) {
> @@ -2077,9 +2085,12 @@ static int virtnet_find_vqs(struct virtnet_info *vi)
>   sprintf(vi->sq[i].name, "output.%d", i);
>   names[rxq2vq(i)] = vi->rq[i].name;
>   names[txq2vq(i)] = vi->sq[i].name;
> + if (ctx)
> + ctx[rxq2vq(i)] = true;
>   }
>  
> - ret = virtio_find_vqs(vi->vdev, total_vqs, vqs, callbacks, names, NULL);
> + ret = vi->vdev->config->find_vqs(vi->vdev, total_vqs, vqs, callbacks,
> +  names, ctx, NULL);

virtio_find_vqs_ctx()? (Needs to be exported, obviously.)

>   if (ret)
>   goto err_find;
>  
> @@ -2101,6 +2112,8 @@ static int virtnet_find_vqs(struct virtnet_info *vi)
>   return 0;
>  
>  err_find:
> + kfree(ctx);
> +err_ctx:
>   kfree(names);
>  err_names:
>   kfree(callbacks);

[PATCH 4/6] virtio_net: allow specifying context for rx

2017-03-29 Thread Michael S. Tsirkin 
With mergeable buffers we never use s/g for rx,
so allow specifying context in that case.

Signed-off-by: Michael S. Tsirkin 
---
 drivers/net/virtio_net.c | 15 ++-
 1 file changed, 14 insertions(+), 1 deletion(-)

diff --git a/drivers/net/virtio_net.c b/drivers/net/virtio_net.c
index 6802169..340f737 100644
--- a/drivers/net/virtio_net.c
+++ b/drivers/net/virtio_net.c
@@ -2044,6 +2044,7 @@ static int virtnet_find_vqs(struct virtnet_info *vi)
int ret = -ENOMEM;
int i, total_vqs;
const char **names;
+   const bool *ctx;
 
/* We expect 1 RX virtqueue followed by 1 TX virtqueue, followed by
 * possible N-1 RX/TX queue pairs used in multiqueue mode, followed by
@@ -2062,6 +2063,13 @@ static int virtnet_find_vqs(struct virtnet_info *vi)
names = kmalloc(total_vqs * sizeof(*names), GFP_KERNEL);
if (!names)
goto err_names;
+   if (vi->mergeable_rx_bufs) {
+   ctx = kzalloc(total_vqs * sizeof(*ctx), GFP_KERNEL);
+   if (!ctx)
+   goto err_ctx;
+   } else {
+   ctx = NULL;
+   }
 
/* Parameters for control virtqueue, if any */
if (vi->has_cvq) {
@@ -2077,9 +2085,12 @@ static int virtnet_find_vqs(struct virtnet_info *vi)
sprintf(vi->sq[i].name, "output.%d", i);
names[rxq2vq(i)] = vi->rq[i].name;
names[txq2vq(i)] = vi->sq[i].name;
+   if (ctx)
+   ctx[rxq2vq(i)] = true;
}
 
-   ret = virtio_find_vqs(vi->vdev, total_vqs, vqs, callbacks, names, NULL);
+   ret = vi->vdev->config->find_vqs(vi->vdev, total_vqs, vqs, callbacks,
+names, ctx, NULL);
if (ret)
goto err_find;
 
@@ -2101,6 +2112,8 @@ static int virtnet_find_vqs(struct virtnet_info *vi)
return 0;
 
 err_find:
+   kfree(ctx);
+err_ctx:
kfree(names);
 err_names:
kfree(callbacks);
-- 
MST