[PATCH] NTB: allocate number transport entries depending on size of ring size

[PATCH] NTB: allocate number transport entries depending on size of ring size

[Dave Jiang]

Currently we only allocate a fixed default number of descriptors for the tx
and rx side. We should dynamically resize it to the number of descriptors
resides in the transport rings. We should know the number of transmit
descriptors at initializaiton. We will allocate the default number of
descriptors for receive side and allocate additional ones when we know the
actual max entries for receive.

Signed-off-by: Dave Jiang <dave.jiang@intel.com>
---
 drivers/ntb/ntb_transport.c |   20 +++++++++++++++++++-
 1 file changed, 19 insertions(+), 1 deletion(-)

diff --git a/drivers/ntb/ntb_transport.c b/drivers/ntb/ntb_transport.c
index 2ef9d913..4f7006a 100644
--- a/drivers/ntb/ntb_transport.c
+++ b/drivers/ntb/ntb_transport.c
@@ -597,9 +597,13 @@ static int ntb_transport_setup_qp_mw(struct ntb_transport_ctx *nt,
 {
 	struct ntb_transport_qp *qp = &nt->qp_vec[qp_num];
 	struct ntb_transport_mw *mw;
+	struct ntb_dev *ndev = nt->ndev;
+	struct ntb_queue_entry *entry;
 	unsigned int rx_size, num_qps_mw;
 	unsigned int mw_num, mw_count, qp_count;
 	unsigned int i;
+	unsigned int rx_entries = 0;
+	int node;
 
 	mw_count = nt->mw_count;
 	qp_count = nt->qp_count;
@@ -626,6 +630,20 @@ static int ntb_transport_setup_qp_mw(struct ntb_transport_ctx *nt,
 	qp->rx_max_entry = rx_size / qp->rx_max_frame;
 	qp->rx_index = 0;
 
+	if (qp->rx_max_entry > NTB_QP_DEF_NUM_ENTRIES)
+		rx_entries = qp->rx_max_entry - NTB_QP_DEF_NUM_ENTRIES;
+
+	node = dev_to_node(&ndev->dev);
+	for (i = 0; i < rx_entries; i++) {
+		entry = kzalloc_node(sizeof(*entry), GFP_ATOMIC, node);
+		if (!entry)
+			return -ENOMEM;
+
+		entry->qp = qp;
+		ntb_list_add(&qp->ntb_rx_q_lock, &entry->entry,
+			     &qp->rx_free_q);
+	}
+
 	qp->remote_rx_info->entry = qp->rx_max_entry - 1;
 
 	/* setup the hdr offsets with 0's */
@@ -1723,7 +1741,7 @@ ntb_transport_create_queue(void *data, struct device *client_dev,
 			     &qp->rx_free_q);
 	}
 
-	for (i = 0; i < NTB_QP_DEF_NUM_ENTRIES; i++) {
+	for (i = 0; i < qp->tx_max_entry; i++) {
 		entry = kzalloc_node(sizeof(*entry), GFP_ATOMIC, node);
 		if (!entry)
 			goto err2;

Re: [PATCH] NTB: allocate number transport entries depending on size of ring size

[Jon Mason]

On Wed, Apr 6, 2016 at 5:26 PM, Dave Jiang <dave.jiang@intel.com> wrote:
> Currently we only allocate a fixed default number of descriptors for the tx
> and rx side. We should dynamically resize it to the number of descriptors
> resides in the transport rings. We should know the number of transmit
> descriptors at initializaiton. We will allocate the default number of
> descriptors for receive side and allocate additional ones when we know the
> actual max entries for receive.
>
> Signed-off-by: Dave Jiang <dave.jiang@intel.com>
> ---
>  drivers/ntb/ntb_transport.c |   20 +++++++++++++++++++-
>  1 file changed, 19 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/ntb/ntb_transport.c b/drivers/ntb/ntb_transport.c
> index 2ef9d913..4f7006a 100644
> --- a/drivers/ntb/ntb_transport.c
> +++ b/drivers/ntb/ntb_transport.c
> @@ -597,9 +597,13 @@ static int ntb_transport_setup_qp_mw(struct ntb_transport_ctx *nt,
>  {
>         struct ntb_transport_qp *qp = &nt->qp_vec[qp_num];
>         struct ntb_transport_mw *mw;
> +       struct ntb_dev *ndev = nt->ndev;
> +       struct ntb_queue_entry *entry;
>         unsigned int rx_size, num_qps_mw;
>         unsigned int mw_num, mw_count, qp_count;
>         unsigned int i;
> +       unsigned int rx_entries = 0;
> +       int node;
>
>         mw_count = nt->mw_count;
>         qp_count = nt->qp_count;
> @@ -626,6 +630,20 @@ static int ntb_transport_setup_qp_mw(struct ntb_transport_ctx *nt,
>         qp->rx_max_entry = rx_size / qp->rx_max_frame;
>         qp->rx_index = 0;
>
> +       if (qp->rx_max_entry > NTB_QP_DEF_NUM_ENTRIES)

I would be good to have a comment here describing what/why this is
being done here.  After thinking about it, I understood why, but who
wants to think when they can read a comment :)

Aside from this, it looks good to me.

Thanks,
Jon

> +               rx_entries = qp->rx_max_entry - NTB_QP_DEF_NUM_ENTRIES;
> +
> +       node = dev_to_node(&ndev->dev);
> +       for (i = 0; i < rx_entries; i++) {
> +               entry = kzalloc_node(sizeof(*entry), GFP_ATOMIC, node);
> +               if (!entry)
> +                       return -ENOMEM;
> +
> +               entry->qp = qp;
> +               ntb_list_add(&qp->ntb_rx_q_lock, &entry->entry,
> +                            &qp->rx_free_q);
> +       }
> +
>         qp->remote_rx_info->entry = qp->rx_max_entry - 1;
>
>         /* setup the hdr offsets with 0's */
> @@ -1723,7 +1741,7 @@ ntb_transport_create_queue(void *data, struct device *client_dev,
>                              &qp->rx_free_q);
>         }
>
> -       for (i = 0; i < NTB_QP_DEF_NUM_ENTRIES; i++) {
> +       for (i = 0; i < qp->tx_max_entry; i++) {
>                 entry = kzalloc_node(sizeof(*entry), GFP_ATOMIC, node);
>                 if (!entry)
>                         goto err2;
>