Re: [dpdk-dev] [PATCH v2] vhost: fix interrupt suppression for the split ring

2019-03-20 Thread Maxime Coquelin 




On 3/17/19 7:38 AM, Jiayu Hu wrote:

The VIRTIO_RING_F_EVENT_IDX feature of split ring might
be broken, as the value of signalled_used is invalid
after live migration, start up and virtio driver reload.
This patch fixes it by using signalled_used_valid.

In addition, this patch makes the VIRTIO_RING_F_EVENT_IDX
implementation of split ring match kernel backend to suppress
more interrupts.

Fixes: e37ff954405a ("vhost: support virtqueue interrupt/notification 
suppression")
Cc:sta...@dpdk.org

Signed-off-by: Jiayu Hu
---
change in v2:
- fix virtio-net driver reload

  lib/librte_vhost/vhost.h  | 12 
  lib/librte_vhost/vhost_user.c |  2 ++
  2 files changed, 10 insertions(+), 4 deletions(-)



Applied to dpdk-next-virtio/master branch.

Thanks,
Maxime

Re: [dpdk-dev] [PATCH v2] vhost: fix interrupt suppression for the split ring

2019-03-19 Thread Tiwei Bie 
On Sun, Mar 17, 2019 at 02:38:32PM +0800, Jiayu Hu wrote:
> The VIRTIO_RING_F_EVENT_IDX feature of split ring might
> be broken, as the value of signalled_used is invalid
> after live migration, start up and virtio driver reload.
> This patch fixes it by using signalled_used_valid.
> 
> In addition, this patch makes the VIRTIO_RING_F_EVENT_IDX
> implementation of split ring match kernel backend to suppress
> more interrupts.
> 
> Fixes: e37ff954405a ("vhost: support virtqueue interrupt/notification 
> suppression")
> Cc: sta...@dpdk.org
> 
> Signed-off-by: Jiayu Hu 
> ---
> change in v2:
> - fix virtio-net driver reload
> 
>  lib/librte_vhost/vhost.h  | 12 
>  lib/librte_vhost/vhost_user.c |  2 ++
>  2 files changed, 10 insertions(+), 4 deletions(-)

Reviewed-by: Tiwei Bie

Re: [dpdk-dev] [PATCH v2] vhost: fix interrupt suppression for the split ring

2019-03-19 Thread Wang, Yinan 
Test-by: Wang, Yinan 

Best Wishes,
Yinan

> -Original Message-
> From: Hu, Jiayu
> Sent: 2019年3月17日 14:39
> To: dev@dpdk.org
> Cc: Bie, Tiwei ; maxime.coque...@redhat.com; Wang,
> Yinan ; Hu, Jiayu ;
> sta...@dpdk.org
> Subject: [PATCH v2] vhost: fix interrupt suppression for the split ring
> 
> The VIRTIO_RING_F_EVENT_IDX feature of split ring might be broken, as the
> value of signalled_used is invalid after live migration, start up and virtio 
> driver
> reload.
> This patch fixes it by using signalled_used_valid.
> 
> In addition, this patch makes the VIRTIO_RING_F_EVENT_IDX implementation
> of split ring match kernel backend to suppress more interrupts.
> 
> Fixes: e37ff954405a ("vhost: support virtqueue interrupt/notification
> suppression")
> Cc: sta...@dpdk.org
> 
> Signed-off-by: Jiayu Hu 
> ---
> change in v2:
> - fix virtio-net driver reload
> 
>  lib/librte_vhost/vhost.h  | 12 
>  lib/librte_vhost/vhost_user.c |  2 ++
>  2 files changed, 10 insertions(+), 4 deletions(-)
> 
> diff --git a/lib/librte_vhost/vhost.h b/lib/librte_vhost/vhost.h index
> f008ec4..e9138df 100644
> --- a/lib/librte_vhost/vhost.h
> +++ b/lib/librte_vhost/vhost.h
> @@ -633,16 +633,20 @@ vhost_vring_call_split(struct virtio_net *dev, struct
> vhost_virtqueue *vq)
>   if (dev->features & (1ULL << VIRTIO_RING_F_EVENT_IDX)) {
>   uint16_t old = vq->signalled_used;
>   uint16_t new = vq->last_used_idx;
> + bool signalled_used_valid = vq->signalled_used_valid;
> +
> + vq->signalled_used = new;
> + vq->signalled_used_valid = true;
> 
>   VHOST_LOG_DEBUG(VHOST_DATA, "%s: used_event_idx=%d,
> old=%d, new=%d\n",
>   __func__,
>   vhost_used_event(vq),
>   old, new);
> - if (vhost_need_event(vhost_used_event(vq), new, old)
> - && (vq->callfd >= 0)) {
> - vq->signalled_used = vq->last_used_idx;
> +
> + if ((vhost_need_event(vhost_used_event(vq), new, old) &&
> + (vq->callfd >= 0)) ||
> + unlikely(!signalled_used_valid))
>   eventfd_write(vq->callfd, (eventfd_t) 1);
> - }
>   } else {
>   /* Kick the guest if necessary. */
>   if (!(vq->avail->flags & VRING_AVAIL_F_NO_INTERRUPT) diff --git
> a/lib/librte_vhost/vhost_user.c b/lib/librte_vhost/vhost_user.c index
> 36c0c67..01a8d80 100644
> --- a/lib/librte_vhost/vhost_user.c
> +++ b/lib/librte_vhost/vhost_user.c
> @@ -1298,6 +1298,8 @@ vhost_user_get_vring_base(struct virtio_net
> **pdev,
> 
>   vq->callfd = VIRTIO_UNINITIALIZED_EVENTFD;
> 
> + vq->signalled_used_valid = false;
> +
>   if (dev->dequeue_zero_copy)
>   free_zmbufs(vq);
>   if (vq_is_packed(dev)) {
> --
> 2.7.4

[dpdk-dev] [PATCH v2] vhost: fix interrupt suppression for the split ring

2019-03-16 Thread Jiayu Hu 
The VIRTIO_RING_F_EVENT_IDX feature of split ring might
be broken, as the value of signalled_used is invalid
after live migration, start up and virtio driver reload.
This patch fixes it by using signalled_used_valid.

In addition, this patch makes the VIRTIO_RING_F_EVENT_IDX
implementation of split ring match kernel backend to suppress
more interrupts.

Fixes: e37ff954405a ("vhost: support virtqueue interrupt/notification 
suppression")
Cc: sta...@dpdk.org

Signed-off-by: Jiayu Hu 
---
change in v2:
- fix virtio-net driver reload

 lib/librte_vhost/vhost.h  | 12 
 lib/librte_vhost/vhost_user.c |  2 ++
 2 files changed, 10 insertions(+), 4 deletions(-)

diff --git a/lib/librte_vhost/vhost.h b/lib/librte_vhost/vhost.h
index f008ec4..e9138df 100644
--- a/lib/librte_vhost/vhost.h
+++ b/lib/librte_vhost/vhost.h
@@ -633,16 +633,20 @@ vhost_vring_call_split(struct virtio_net *dev, struct 
vhost_virtqueue *vq)
if (dev->features & (1ULL << VIRTIO_RING_F_EVENT_IDX)) {
uint16_t old = vq->signalled_used;
uint16_t new = vq->last_used_idx;
+   bool signalled_used_valid = vq->signalled_used_valid;
+
+   vq->signalled_used = new;
+   vq->signalled_used_valid = true;
 
VHOST_LOG_DEBUG(VHOST_DATA, "%s: used_event_idx=%d, old=%d, 
new=%d\n",
__func__,
vhost_used_event(vq),
old, new);
-   if (vhost_need_event(vhost_used_event(vq), new, old)
-   && (vq->callfd >= 0)) {
-   vq->signalled_used = vq->last_used_idx;
+
+   if ((vhost_need_event(vhost_used_event(vq), new, old) &&
+   (vq->callfd >= 0)) ||
+   unlikely(!signalled_used_valid))
eventfd_write(vq->callfd, (eventfd_t) 1);
-   }
} else {
/* Kick the guest if necessary. */
if (!(vq->avail->flags & VRING_AVAIL_F_NO_INTERRUPT)
diff --git a/lib/librte_vhost/vhost_user.c b/lib/librte_vhost/vhost_user.c
index 36c0c67..01a8d80 100644
--- a/lib/librte_vhost/vhost_user.c
+++ b/lib/librte_vhost/vhost_user.c
@@ -1298,6 +1298,8 @@ vhost_user_get_vring_base(struct virtio_net **pdev,
 
vq->callfd = VIRTIO_UNINITIALIZED_EVENTFD;
 
+   vq->signalled_used_valid = false;
+
if (dev->dequeue_zero_copy)
free_zmbufs(vq);
if (vq_is_packed(dev)) {
-- 
2.7.4