Re: [dpdk-dev] [PATCH 2/4] net/mlx5: add reference counter for DV/DR structures

[Shahaf Shuler <shahafs@mellanox.com>]

Tuesday, April 2, 2019 9:23 AM, Viacheslav Ovsiienko:
> Subject: [PATCH 2/4] net/mlx5: add reference counter for DV/DR structures

Same comment about the title. 

> 
> This patch introduces the reference counter for DV/DR flow engine
> structure, which we are going to share between master and representors in
> E-Switch configurations over multiport Infiniband device.
> 
> Signed-off-by: Viacheslav Ovsiienko <viacheslavo@mellanox.com>
> ---
>  drivers/net/mlx5/mlx5.c | 26 ++++++++++++++++++++++++--
> drivers/net/mlx5/mlx5.h |  4 ++++
>  2 files changed, 28 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/net/mlx5/mlx5.c b/drivers/net/mlx5/mlx5.c index
> 9de122d..79e0c17 100644
> --- a/drivers/net/mlx5/mlx5.c
> +++ b/drivers/net/mlx5/mlx5.c
> @@ -299,7 +299,8 @@ struct mlx5_dev_spawn_data {  #ifdef
> HAVE_MLX5DV_DR
>  /**
>   * Initialize DV/DR related data within private structure.
> - * This is preparation step for the data sharing.
> + * Routine checks the reference counter and does actual
> + * resources creation/iniialization only if counter is zero.
>   *
>   * @param[in] priv
>   *   Pointer to the private device data structure.
> @@ -314,6 +315,14 @@ struct mlx5_dev_spawn_data {
>  	int err = 0;
>  	void *ns;
> 
> +	assert(sh);
> +	if (sh->dv_refcnt) {
> +		/* Shared DV/DR structures is already initialized. */
> +		sh->dv_refcnt++;
> +		priv->dv_shared = 1;
> +		return 0;
> +	}
> +	/* Reference counter is zero, we should initialize structures. */
>  	ns = mlx5dv_dr_create_ns(sh->ctx,
> MLX5DV_DR_NS_DOMAIN_INGRESS_BYPASS);
>  	if (!ns) {
>  		DRV_LOG(ERR, "ingress mlx5dv_dr_create_ns failed"); @@ -
> 328,6 +337,8 @@ struct mlx5_dev_spawn_data {
>  		goto error;
>  	}
>  	priv->tx_ns = ns;
> +	sh->dv_refcnt++;
> +	priv->dv_shared = 1;
>  	return 0;
> 
>  error:
> @@ -352,6 +363,16 @@ struct mlx5_dev_spawn_data {  static void
> mlx5_free_shared_dv(struct mlx5_priv *priv)  {
> +	struct mlx5_ibv_shared *sh;
> +
> +	if (!priv->dv_shared)
> +		return;
> +	priv->dv_shared = 0;
> +	sh = priv->sh;
> +	assert(sh);
> +	assert(sh->dv_refcnt);
> +	if (sh->dv_refcnt && --sh->dv_refcnt)
> +		return;
>  	if (priv->rx_ns) {
>  		mlx5dv_dr_destroy_ns(priv->rx_ns);
>  		priv->rx_ns = NULL;
> @@ -1491,7 +1512,8 @@ struct mlx5_dev_spawn_data {
>  error:
>  	if (priv) {
>  #ifdef HAVE_MLX5DV_DR
> -		mlx5_free_shared_dv(priv);
> +		if (priv->sh)
> +			mlx5_free_shared_dv(priv);
>  #endif
>  		if (priv->nl_socket_route >= 0)
>  			close(priv->nl_socket_route);
> diff --git a/drivers/net/mlx5/mlx5.h b/drivers/net/mlx5/mlx5.h index
> a3d5f8e..56a2c61 100644
> --- a/drivers/net/mlx5/mlx5.h
> +++ b/drivers/net/mlx5/mlx5.h
> @@ -213,6 +213,9 @@ struct mlx5_ibv_shared {
>  	char ibdev_name[IBV_SYSFS_NAME_MAX]; /* IB device name. */
>  	char ibdev_path[IBV_SYSFS_PATH_MAX]; /* IB device path for
> secondary */
>  	struct ibv_device_attr_ex device_attr; /* Device properties. */
> +	/* Shared DV/DR flow data section. */
> +	uint32_t dv_refcnt; /* DV/DR data reference counter. */
> +	/* Shared interrupt handler section. */
>  	pthread_mutex_t intr_mutex; /* Interrupt config mutex. */
>  	uint32_t intr_cnt; /* Interrupt handler reference counter. */
>  	struct rte_intr_handle intr_handle; /* Interrupt handler for device.
> */ @@ -244,6 +247,7 @@ struct mlx5_priv {
>  	unsigned int isolated:1; /* Whether isolated mode is enabled. */
>  	unsigned int representor:1; /* Device is a port representor. */
>  	unsigned int master:1; /* Device is a E-Switch master. */
> +	unsigned int dv_shared:1; /* DV/DR data is shared. */

Why this flags is needed? Aren't we always going to share? 


>  	uint16_t domain_id; /* Switch domain identifier. */
>  	uint16_t vport_id; /* Associated VF vport index (if any). */
>  	int32_t representor_id; /* Port representor identifier. */
> --
> 1.8.3.1