Re: [dpdk-dev] [PATCH 1/3] vdpa/mlx5: manage virtqs by array

[Matan Azrad <matan@mellanox.com>]

Hi Maxime

From: Maxime Coquelin
> On 3/31/20 1:12 PM, Matan Azrad wrote:
> > As a preparation to listen the virtqs status before the device is
> > configured, manage the virtqs structures in array instead of list.
> >
> > Signed-off-by: Matan Azrad <matan@mellanox.com>
> > Acked-by: Viacheslav Ovsiienko <viacheslavo@mellanox.com>
> > ---
> >  drivers/vdpa/mlx5/mlx5_vdpa.c       | 43 ++++++++++++++++----------------
> --
> >  drivers/vdpa/mlx5/mlx5_vdpa.h       |  2 +-
> >  drivers/vdpa/mlx5/mlx5_vdpa_lm.c    | 43 ++++++++++++++++--------------
> ----
> >  drivers/vdpa/mlx5/mlx5_vdpa_steer.c | 18 +++++++--------
> > drivers/vdpa/mlx5/mlx5_vdpa_virtq.c | 46
> > +++++++++++++++----------------------
> >  5 files changed, 68 insertions(+), 84 deletions(-)
> >
> > diff --git a/drivers/vdpa/mlx5/mlx5_vdpa.c
> > b/drivers/vdpa/mlx5/mlx5_vdpa.c index f10647b..b22f074 100644
> > --- a/drivers/vdpa/mlx5/mlx5_vdpa.c
> > +++ b/drivers/vdpa/mlx5/mlx5_vdpa.c
> > @@ -116,20 +116,18 @@
> >  {
> >  	int did = rte_vhost_get_vdpa_device_id(vid);
> >  	struct mlx5_vdpa_priv *priv =
> mlx5_vdpa_find_priv_resource_by_did(did);
> > -	struct mlx5_vdpa_virtq *virtq = NULL;
> >
> >  	if (priv == NULL) {
> >  		DRV_LOG(ERR, "Invalid device id: %d.", did);
> >  		return -EINVAL;
> >  	}
> > -	SLIST_FOREACH(virtq, &priv->virtq_list, next)
> > -		if (virtq->index == vring)
> > -			break;
> > -	if (!virtq) {
> > +	if (!priv->configured || vring >= RTE_MIN((int)priv->nr_virtqs,
> > +	    (int)priv->caps.max_num_virtio_queues * 2) ||
> > +	    !priv->virtqs[vring].virtq) {
> >  		DRV_LOG(ERR, "Invalid or unconfigured vring id: %d.", vring);
> >  		return -EINVAL;
> >  	}
> > -	return mlx5_vdpa_virtq_enable(virtq, state);
> > +	return mlx5_vdpa_virtq_enable(&priv->virtqs[vring], state);
> >  }
> >
> >  static int
> > @@ -482,28 +480,28 @@
> >  		rte_errno = ENODEV;
> >  		return -rte_errno;
> >  	}
> > -	priv = rte_zmalloc("mlx5 vDPA device private", sizeof(*priv),
> > -			   RTE_CACHE_LINE_SIZE);
> > -	if (!priv) {
> > -		DRV_LOG(ERR, "Failed to allocate private memory.");
> > -		rte_errno = ENOMEM;
> > -		goto error;
> > -	}
> >  	ret = mlx5_devx_cmd_query_hca_attr(ctx, &attr);
> >  	if (ret) {
> >  		DRV_LOG(ERR, "Unable to read HCA capabilities.");
> >  		rte_errno = ENOTSUP;
> >  		goto error;
> > -	} else {
> > -		if (!attr.vdpa.valid || !attr.vdpa.max_num_virtio_queues) {
> > -			DRV_LOG(ERR, "Not enough capabilities to support
> vdpa,"
> > -				" maybe old FW/OFED version?");
> > -			rte_errno = ENOTSUP;
> > -			goto error;
> > -		}
> > -		priv->caps = attr.vdpa;
> > -		priv->log_max_rqt_size = attr.log_max_rqt_size;
> > +	} else if (!attr.vdpa.valid || !attr.vdpa.max_num_virtio_queues) {
> > +		DRV_LOG(ERR, "Not enough capabilities to support vdpa,
> maybe "
> > +			"old FW/OFED version?");
> > +		rte_errno = ENOTSUP;
> > +		goto error;
> > +	}
> > +	priv = rte_zmalloc("mlx5 vDPA device private", sizeof(*priv) +
> > +			   sizeof(struct mlx5_vdpa_virtq) *
> > +			   attr.vdpa.max_num_virtio_queues * 2,
> > +			   RTE_CACHE_LINE_SIZE);
> > +	if (!priv) {
> > +		DRV_LOG(ERR, "Failed to allocate private memory.");
> > +		rte_errno = ENOMEM;
> > +		goto error;
> >  	}
> > +	priv->caps = attr.vdpa;
> > +	priv->log_max_rqt_size = attr.log_max_rqt_size;
> >  	priv->ctx = ctx;
> >  	priv->dev_addr.pci_addr = pci_dev->addr;
> >  	priv->dev_addr.type = PCI_ADDR;
> > @@ -519,7 +517,6 @@
> >  		goto error;
> >  	}
> >  	SLIST_INIT(&priv->mr_list);
> > -	SLIST_INIT(&priv->virtq_list);
> >  	pthread_mutex_lock(&priv_list_lock);
> >  	TAILQ_INSERT_TAIL(&priv_list, priv, next);
> >  	pthread_mutex_unlock(&priv_list_lock);
> > diff --git a/drivers/vdpa/mlx5/mlx5_vdpa.h
> > b/drivers/vdpa/mlx5/mlx5_vdpa.h index 75af410..baec106 100644
> > --- a/drivers/vdpa/mlx5/mlx5_vdpa.h
> > +++ b/drivers/vdpa/mlx5/mlx5_vdpa.h
> > @@ -120,11 +120,11 @@ struct mlx5_vdpa_priv {
> >  	uint16_t nr_virtqs;
> >  	uint64_t features; /* Negotiated features. */
> >  	uint16_t log_max_rqt_size;
> > -	SLIST_HEAD(virtq_list, mlx5_vdpa_virtq) virtq_list;
> >  	struct mlx5_vdpa_steer steer;
> >  	struct mlx5dv_var *var;
> >  	void *virtq_db_addr;
> >  	SLIST_HEAD(mr_list, mlx5_vdpa_query_mr) mr_list;
> > +	struct mlx5_vdpa_virtq virtqs[];
> >  };
> >
> >  /**
> > diff --git a/drivers/vdpa/mlx5/mlx5_vdpa_lm.c
> > b/drivers/vdpa/mlx5/mlx5_vdpa_lm.c
> > index 4457760..77f2eda 100644
> > --- a/drivers/vdpa/mlx5/mlx5_vdpa_lm.c
> > +++ b/drivers/vdpa/mlx5/mlx5_vdpa_lm.c
> > @@ -15,13 +15,12 @@
> >  		.type =
> MLX5_VIRTQ_MODIFY_TYPE_DIRTY_BITMAP_DUMP_ENABLE,
> >  		.dirty_bitmap_dump_enable = enable,
> >  	};
> > -	struct mlx5_vdpa_virtq *virtq;
> > +	int i;
> >
> > -	SLIST_FOREACH(virtq, &priv->virtq_list, next) {
> > -		attr.queue_index = virtq->index;
> > -		if (mlx5_devx_cmd_modify_virtq(virtq->virtq, &attr)) {
> > -			DRV_LOG(ERR, "Failed to modify virtq %d logging.",
> > -				virtq->index);
> > +	for (i = 0; i < priv->nr_virtqs; ++i) {
> > +		attr.queue_index = i;
> > +		if (mlx5_devx_cmd_modify_virtq(priv->virtqs[i].virtq, &attr))
> {
> > +			DRV_LOG(ERR, "Failed to modify virtq %d logging.",
> i);
> >  			return -1;
> >  		}
> >  	}
> > @@ -47,7 +46,7 @@
> >  		.dirty_bitmap_size = log_size,
> >  	};
> >  	struct mlx5_vdpa_query_mr *mr = rte_malloc(__func__,
> sizeof(*mr), 0);
> > -	struct mlx5_vdpa_virtq *virtq;
> > +	int i;
> >
> >  	if (!mr) {
> >  		DRV_LOG(ERR, "Failed to allocate mem for lm mr."); @@ -
> 67,11 +66,10
> > @@
> >  		goto err;
> >  	}
> >  	attr.dirty_bitmap_mkey = mr->mkey->id;
> > -	SLIST_FOREACH(virtq, &priv->virtq_list, next) {
> > -		attr.queue_index = virtq->index;
> > -		if (mlx5_devx_cmd_modify_virtq(virtq->virtq, &attr)) {
> > -			DRV_LOG(ERR, "Failed to modify virtq %d for lm.",
> > -				virtq->index);
> > +	for (i = 0; i < priv->nr_virtqs; ++i) {
> > +		attr.queue_index = i;
> > +		if (mlx5_devx_cmd_modify_virtq(priv->virtqs[i].virtq, &attr))
> {
> > +			DRV_LOG(ERR, "Failed to modify virtq %d for lm.", i);
> >  			goto err;
> >  		}
> >  	}
> > @@ -94,9 +92,9 @@
> >  mlx5_vdpa_lm_log(struct mlx5_vdpa_priv *priv)  {
> >  	struct mlx5_devx_virtq_attr attr = {0};
> > -	struct mlx5_vdpa_virtq *virtq;
> >  	uint64_t features;
> >  	int ret = rte_vhost_get_negotiated_features(priv->vid, &features);
> > +	int i;
> >
> >  	if (ret) {
> >  		DRV_LOG(ERR, "Failed to get negotiated features."); @@ -
> 104,27
> > +102,26 @@
> >  	}
> >  	if (!RTE_VHOST_NEED_LOG(features))
> >  		return 0;
> > -	SLIST_FOREACH(virtq, &priv->virtq_list, next) {
> > -		ret = mlx5_vdpa_virtq_modify(virtq, 0);
> > +	for (i = 0; i < priv->nr_virtqs; ++i) {
> > +		ret = mlx5_vdpa_virtq_modify(&priv->virtqs[i], 0);
> >  		if (ret)
> >  			return -1;
> > -		if (mlx5_devx_cmd_query_virtq(virtq->virtq, &attr)) {
> > -			DRV_LOG(ERR, "Failed to query virtq %d.", virtq-
> >index);
> > +		if (mlx5_devx_cmd_query_virtq(priv->virtqs[i].virtq, &attr)) {
> > +			DRV_LOG(ERR, "Failed to query virtq %d.", i);
> >  			return -1;
> >  		}
> >  		DRV_LOG(INFO, "Query vid %d vring %d:
> hw_available_idx=%d, "
> > -			"hw_used_index=%d", priv->vid, virtq->index,
> > +			"hw_used_index=%d", priv->vid, i,
> >  			attr.hw_available_index, attr.hw_used_index);
> > -		ret = rte_vhost_set_vring_base(priv->vid, virtq->index,
> > +		ret = rte_vhost_set_vring_base(priv->vid, i,
> >  					       attr.hw_available_index,
> >  					       attr.hw_used_index);
> >  		if (ret) {
> > -			DRV_LOG(ERR, "Failed to set virtq %d base.",
> > -				virtq->index);
> > +			DRV_LOG(ERR, "Failed to set virtq %d base.", i);
> >  			return -1;
> >  		}
> > -		rte_vhost_log_used_vring(priv->vid, virtq->index, 0,
> > -				       MLX5_VDPA_USED_RING_LEN(virtq-
> >vq_size));
> > +		rte_vhost_log_used_vring(priv->vid, i, 0,
> > +			      MLX5_VDPA_USED_RING_LEN(priv-
> >virtqs[i].vq_size));
> >  	}
> >  	return 0;
> >  }
> > diff --git a/drivers/vdpa/mlx5/mlx5_vdpa_steer.c
> > b/drivers/vdpa/mlx5/mlx5_vdpa_steer.c
> > index 9c11452..96ffc21 100644
> > --- a/drivers/vdpa/mlx5/mlx5_vdpa_steer.c
> > +++ b/drivers/vdpa/mlx5/mlx5_vdpa_steer.c
> > @@ -76,13 +76,13 @@
> >  static int
> >  mlx5_vdpa_rqt_prepare(struct mlx5_vdpa_priv *priv)  {
> > -	struct mlx5_vdpa_virtq *virtq;
> > +	int i;
> >  	uint32_t rqt_n = RTE_MIN(MLX5_VDPA_DEFAULT_RQT_SIZE,
> >  				 1 << priv->log_max_rqt_size);
> >  	struct mlx5_devx_rqt_attr *attr = rte_zmalloc(__func__,
> sizeof(*attr)
> >  						      + rqt_n *
> >  						      sizeof(uint32_t), 0);
> > -	uint32_t i = 0, j;
> > +	uint32_t k = 0, j;
> >  	int ret = 0;
> >
> >  	if (!attr) {
> > @@ -90,15 +90,15 @@
> >  		rte_errno = ENOMEM;
> >  		return -ENOMEM;
> >  	}
> > -	SLIST_FOREACH(virtq, &priv->virtq_list, next) {
> > -		if (is_virtq_recvq(virtq->index, priv->nr_virtqs) &&
> > -		    virtq->enable) {
> > -			attr->rq_list[i] = virtq->virtq->id;
> > -			i++;
> > +	for (i = 0; i < priv->nr_virtqs; i++) {
> > +		if (is_virtq_recvq(i, priv->nr_virtqs) &&
> > +		    priv->virtqs[i].enable) {
> > +			attr->rq_list[k] = priv->virtqs[i].virtq->id;
> > +			k++;
> >  		}
> >  	}
> > -	for (j = 0; i != rqt_n; ++i, ++j)
> > -		attr->rq_list[i] = attr->rq_list[j];
> > +	for (j = 0; k != rqt_n; ++k, ++j)
> > +		attr->rq_list[k] = attr->rq_list[j];
> >  	attr->rq_type = MLX5_INLINE_Q_TYPE_VIRTQ;
> >  	attr->rqt_max_size = rqt_n;
> >  	attr->rqt_actual_size = rqt_n;
> > diff --git a/drivers/vdpa/mlx5/mlx5_vdpa_virtq.c
> > b/drivers/vdpa/mlx5/mlx5_vdpa_virtq.c
> > index 8bebb92..3575272 100644
> > --- a/drivers/vdpa/mlx5/mlx5_vdpa_virtq.c
> > +++ b/drivers/vdpa/mlx5/mlx5_vdpa_virtq.c
> > @@ -59,12 +59,9 @@
> >  				usleep(MLX5_VDPA_INTR_RETRIES_USEC);
> >  			}
> >  		}
> > -		virtq->intr_handle.fd = -1;
> >  	}
> > -	if (virtq->virtq) {
> > +	if (virtq->virtq)
> >  		claim_zero(mlx5_devx_cmd_destroy(virtq->virtq));
> > -		virtq->virtq = NULL;
> > -	}
> >  	for (i = 0; i < RTE_DIM(virtq->umems); ++i) {
> >  		if (virtq->umems[i].obj)
> >  			claim_zero(mlx5_glue->devx_umem_dereg
> > @@ -72,27 +69,20 @@
> >  		if (virtq->umems[i].buf)
> >  			rte_free(virtq->umems[i].buf);
> >  	}
> > -	memset(&virtq->umems, 0, sizeof(virtq->umems));
> >  	if (virtq->eqp.fw_qp)
> >  		mlx5_vdpa_event_qp_destroy(&virtq->eqp);
> > +	memset(virtq, 0, sizeof(*virtq));
> > +	virtq->intr_handle.fd = -1;
> >  	return 0;
> >  }
> >
> >  void
> >  mlx5_vdpa_virtqs_release(struct mlx5_vdpa_priv *priv)  {
> > -	struct mlx5_vdpa_virtq *entry;
> > -	struct mlx5_vdpa_virtq *next;
> > +	int i;
> >
> > -	entry = SLIST_FIRST(&priv->virtq_list);
> > -	while (entry) {
> > -		next = SLIST_NEXT(entry, next);
> > -		mlx5_vdpa_virtq_unset(entry);
> > -		SLIST_REMOVE(&priv->virtq_list, entry, mlx5_vdpa_virtq,
> next);
> > -		rte_free(entry);
> > -		entry = next;
> > -	}
> > -	SLIST_INIT(&priv->virtq_list);
> > +	for (i = 0; i < priv->nr_virtqs; i++)
> > +		mlx5_vdpa_virtq_unset(&priv->virtqs[i]);
> >  	if (priv->tis) {
> >  		claim_zero(mlx5_devx_cmd_destroy(priv->tis));
> >  		priv->tis = NULL;
> > @@ -106,6 +96,7 @@
> >  		priv->virtq_db_addr = NULL;
> >  	}
> >  	priv->features = 0;
> > +	priv->nr_virtqs = 0;
> >  }
> >
> >  int
> > @@ -140,9 +131,9 @@
> >  }
> >
> >  static int
> > -mlx5_vdpa_virtq_setup(struct mlx5_vdpa_priv *priv,
> > -		      struct mlx5_vdpa_virtq *virtq, int index)
> > +mlx5_vdpa_virtq_setup(struct mlx5_vdpa_priv *priv, int index)
> >  {
> > +	struct mlx5_vdpa_virtq *virtq = &priv->virtqs[index];
> >  	struct rte_vhost_vring vq;
> >  	struct mlx5_devx_virtq_attr attr = {0};
> >  	uint64_t gpa;
> > @@ -340,7 +331,6 @@
> >  mlx5_vdpa_virtqs_prepare(struct mlx5_vdpa_priv *priv)  {
> >  	struct mlx5_devx_tis_attr tis_attr = {0};
> > -	struct mlx5_vdpa_virtq *virtq;
> >  	uint32_t i;
> >  	uint16_t nr_vring = rte_vhost_get_vring_num(priv->vid);
> >  	int ret = rte_vhost_get_negotiated_features(priv->vid,
> > &priv->features); @@ -349,6 +339,12 @@
> >  		DRV_LOG(ERR, "Failed to configure negotiated features.");
> >  		return -1;
> >  	}
> > +	if (nr_vring > priv->caps.max_num_virtio_queues * 2) {
> > +		DRV_LOG(ERR, "Do not support more than %d virtqs(%d).",
> > +			(int)priv->caps.max_num_virtio_queues * 2,
> > +			(int)nr_vring);
> > +		return -E2BIG;
> 
> All returns in thid function are either -1 or 0 except this one, so it looks
> inconsistent.
You can find the consistent in negative values for error.
If you insist and this is your only concern here, I agree to change to -1.
Can it be done in integration? 

> 
> > +	}
> >  	/* Always map the entire page. */
> >  	priv->virtq_db_addr = mmap(NULL, priv->var->length, PROT_READ |
> >  				   PROT_WRITE, MAP_SHARED, priv->ctx-
> >cmd_fd, @@ -372,16 +368,10
> > @@
> >  		DRV_LOG(ERR, "Failed to create TIS.");
> >  		goto error;
> >  	}
> > -	for (i = 0; i < nr_vring; i++) {
> > -		virtq = rte_zmalloc(__func__, sizeof(*virtq), 0);
> > -		if (!virtq || mlx5_vdpa_virtq_setup(priv, virtq, i)) {
> > -			if (virtq)
> > -				rte_free(virtq);
> > -			goto error;
> > -		}
> > -		SLIST_INSERT_HEAD(&priv->virtq_list, virtq, next);
> > -	}
> >  	priv->nr_virtqs = nr_vring;
> > +	for (i = 0; i < nr_vring; i++)
> > +		if (mlx5_vdpa_virtq_setup(priv, i))
> > +			goto error;
> >  	return 0;
> >  error:
> >  	mlx5_vdpa_virtqs_release(priv);
> >