RE: [PATCH v2 2/2] virtio-pci: check name when counting MSI-X vectors

2020-01-05 Thread Wang, Wei W
On Saturday, January 4, 2020 2:41 AM, Daniel Verkamp wrote:
> Subject: [PATCH v2 2/2] virtio-pci: check name when counting MSI-X vectors
> 
> VQs without a name specified are not valid; they are skipped in the later loop
> that assigns MSI-X vectors to queues, but the per_vq_vectors loop above that
> counts the required number of vectors previously still counted any queue with 
> a
> non-NULL callback as needing a vector.
> 
> Add a check to the per_vq_vectors loop so that vectors with no name are not
> counted to make the two loops consistent.  This prevents over-counting
> unnecessary vectors (e.g. for features which were not negotiated with the
> device).
> 
> Cc: sta...@vger.kernel.org
> Fixes: 86a559787e6f ("virtio-balloon: VIRTIO_BALLOON_F_FREE_PAGE_HINT")
> Reviewed-by: Cornelia Huck 
> Signed-off-by: Daniel Verkamp 
> ---
> 
> v1:
> https://lists.linuxfoundation.org/pipermail/virtualization/2019-December/0448
> 28.html
> 
>  drivers/virtio/virtio_pci_common.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/drivers/virtio/virtio_pci_common.c
> b/drivers/virtio/virtio_pci_common.c
> index f2862f66c2ac..222d630c41fc 100644
> --- a/drivers/virtio/virtio_pci_common.c
> +++ b/drivers/virtio/virtio_pci_common.c
> @@ -294,7 +294,7 @@ static int vp_find_vqs_msix(struct virtio_device *vdev,
> unsigned nvqs,
>   /* Best option: one for change interrupt, one per vq. */
>   nvectors = 1;
>   for (i = 0; i < nvqs; ++i)
> - if (callbacks[i])
> + if (names[i] && callbacks[i])
>   ++nvectors;
>   } else {
>   /* Second best: one for change, shared for all vqs. */
> --
> 2.24.1.735.g03f4e72817-goog

Reviewed-by: Wang, Wei W 

Best,
Wei
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[PATCH v2 2/2] virtio-pci: check name when counting MSI-X vectors

2020-01-03 Thread Daniel Verkamp
VQs without a name specified are not valid; they are skipped in the
later loop that assigns MSI-X vectors to queues, but the per_vq_vectors
loop above that counts the required number of vectors previously still
counted any queue with a non-NULL callback as needing a vector.

Add a check to the per_vq_vectors loop so that vectors with no name are
not counted to make the two loops consistent.  This prevents
over-counting unnecessary vectors (e.g. for features which were not
negotiated with the device).

Cc: sta...@vger.kernel.org
Fixes: 86a559787e6f ("virtio-balloon: VIRTIO_BALLOON_F_FREE_PAGE_HINT")
Reviewed-by: Cornelia Huck 
Signed-off-by: Daniel Verkamp 
---

v1:
https://lists.linuxfoundation.org/pipermail/virtualization/2019-December/044828.html

 drivers/virtio/virtio_pci_common.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/virtio/virtio_pci_common.c 
b/drivers/virtio/virtio_pci_common.c
index f2862f66c2ac..222d630c41fc 100644
--- a/drivers/virtio/virtio_pci_common.c
+++ b/drivers/virtio/virtio_pci_common.c
@@ -294,7 +294,7 @@ static int vp_find_vqs_msix(struct virtio_device *vdev, 
unsigned nvqs,
/* Best option: one for change interrupt, one per vq. */
nvectors = 1;
for (i = 0; i < nvqs; ++i)
-   if (callbacks[i])
+   if (names[i] && callbacks[i])
++nvectors;
} else {
/* Second best: one for change, shared for all vqs. */
-- 
2.24.1.735.g03f4e72817-goog

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