diff mbox series

[v2,2/2] vdpa/mlx5: retry VAR allocation during vDPA restart

Message ID 20211015150545.1673312-2-xuemingl@nvidia.com (mailing list archive)
State Accepted, archived
Delegated to: Maxime Coquelin
Headers show
Series [v2,1/2] vdpa/mlx5: workaround FW first completion in start | expand

Checks

Context Check Description
ci/iol-aarch64-compile-testing success Testing PASS
ci/intel-Testing success Testing PASS
ci/Intel-compilation success Compilation OK
ci/iol-aarch64-unit-testing success Testing PASS
ci/iol-mellanox-Performance success Performance Testing PASS
ci/iol-x86_64-compile-testing success Testing PASS
ci/iol-x86_64-unit-testing success Testing PASS
ci/iol-intel-Performance success Performance Testing PASS
ci/iol-intel-Functional success Functional Testing PASS
ci/iol-broadcom-Performance success Performance Testing PASS
ci/iol-broadcom-Functional success Functional Testing PASS
ci/github-robot: build success github build: passed
ci/checkpatch success coding style OK

Commit Message

Xueming(Steven) Li Oct. 15, 2021, 3:05 p.m. UTC
VAR is the device memory space for the virtio queues doorbells, qemu
could mmap it to directly to speed up doorbell push.

On a busy system, Qemu takes time to release VAR resources during driver
shutdown. If vdpa restarted quickly, the VAR allocation failed with
error 28 since the VAR is singleton resource per device.

This patch adds retry mechanism for VAR allocation.

Fixes: 4cae722c1b06 ("vdpa/mlx5: move virtual doorbell alloc to probe")
Cc: stable@dpdk.org

Signed-off-by: Xueming Li <xuemingl@nvidia.com>
Reviewed-by: Matan Azrad <matan@nvidia.com>
---
 drivers/vdpa/mlx5/mlx5_vdpa.c | 9 ++++++++-
 1 file changed, 8 insertions(+), 1 deletion(-)

Comments

Maxime Coquelin Oct. 21, 2021, 9:40 a.m. UTC | #1
On 10/15/21 17:05, Xueming Li wrote:
> VAR is the device memory space for the virtio queues doorbells, qemu
> could mmap it to directly to speed up doorbell push.
> 
> On a busy system, Qemu takes time to release VAR resources during driver
> shutdown. If vdpa restarted quickly, the VAR allocation failed with
> error 28 since the VAR is singleton resource per device.
> 
> This patch adds retry mechanism for VAR allocation.
> 
> Fixes: 4cae722c1b06 ("vdpa/mlx5: move virtual doorbell alloc to probe")
> Cc: stable@dpdk.org
> 
> Signed-off-by: Xueming Li <xuemingl@nvidia.com>
> Reviewed-by: Matan Azrad <matan@nvidia.com>
> ---
>   drivers/vdpa/mlx5/mlx5_vdpa.c | 9 ++++++++-
>   1 file changed, 8 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/vdpa/mlx5/mlx5_vdpa.c b/drivers/vdpa/mlx5/mlx5_vdpa.c
> index 6d17d7a6f3e..991739e9840 100644
> --- a/drivers/vdpa/mlx5/mlx5_vdpa.c
> +++ b/drivers/vdpa/mlx5/mlx5_vdpa.c
> @@ -693,7 +693,14 @@ mlx5_vdpa_dev_probe(struct rte_device *dev)
>   	if (attr.num_lag_ports == 0)
>   		priv->num_lag_ports = 1;
>   	priv->ctx = ctx;
> -	priv->var = mlx5_glue->dv_alloc_var(ctx, 0);
> +	for (retry = 0; retry < 7; retry++) {
> +		priv->var = mlx5_glue->dv_alloc_var(ctx, 0);
> +		if (priv->var != NULL)
> +			break;
> +		DRV_LOG(WARNING, "Failed to allocate VAR, retry %d.\n", retry);
> +		/* Wait Qemu release VAR during vdpa restart, 0.1 sec based. */
> +		usleep(100000U << retry);
> +	}
>   	if (!priv->var) {
>   		DRV_LOG(ERR, "Failed to allocate VAR %u.", errno);
>   		goto error;
> 

Reviewed-by: Maxime Coquelin <maxime.coquelin@redhat.com>

Thanks,
Maxime
Maxime Coquelin Oct. 21, 2021, 12:27 p.m. UTC | #2
On 10/15/21 17:05, Xueming Li wrote:
> VAR is the device memory space for the virtio queues doorbells, qemu
> could mmap it to directly to speed up doorbell push.
> 
> On a busy system, Qemu takes time to release VAR resources during driver
> shutdown. If vdpa restarted quickly, the VAR allocation failed with
> error 28 since the VAR is singleton resource per device.
> 
> This patch adds retry mechanism for VAR allocation.
> 
> Fixes: 4cae722c1b06 ("vdpa/mlx5: move virtual doorbell alloc to probe")
> Cc: stable@dpdk.org
> 
> Signed-off-by: Xueming Li <xuemingl@nvidia.com>
> Reviewed-by: Matan Azrad <matan@nvidia.com>
> ---
>   drivers/vdpa/mlx5/mlx5_vdpa.c | 9 ++++++++-
>   1 file changed, 8 insertions(+), 1 deletion(-)


Applied to dpdk-next-virtio/main.

Thanks,
Maxime
diff mbox series

Patch

diff --git a/drivers/vdpa/mlx5/mlx5_vdpa.c b/drivers/vdpa/mlx5/mlx5_vdpa.c
index 6d17d7a6f3e..991739e9840 100644
--- a/drivers/vdpa/mlx5/mlx5_vdpa.c
+++ b/drivers/vdpa/mlx5/mlx5_vdpa.c
@@ -693,7 +693,14 @@  mlx5_vdpa_dev_probe(struct rte_device *dev)
 	if (attr.num_lag_ports == 0)
 		priv->num_lag_ports = 1;
 	priv->ctx = ctx;
-	priv->var = mlx5_glue->dv_alloc_var(ctx, 0);
+	for (retry = 0; retry < 7; retry++) {
+		priv->var = mlx5_glue->dv_alloc_var(ctx, 0);
+		if (priv->var != NULL)
+			break;
+		DRV_LOG(WARNING, "Failed to allocate VAR, retry %d.\n", retry);
+		/* Wait Qemu release VAR during vdpa restart, 0.1 sec based. */
+		usleep(100000U << retry);
+	}
 	if (!priv->var) {
 		DRV_LOG(ERR, "Failed to allocate VAR %u.", errno);
 		goto error;