[dpdk-dev] [PATCH] net/vmxnet3: fix queue size changes

[Jan Blunck]

On Mon, Mar 13, 2017 at 11:41 PM, Charles (Chas) Williams
<ciwillia at brocade.com> wrote:
> If the user reconfigures the queues size, then the previosly allocated
> memzone may potentially be too small.  Instead, always free the old
> memzone and allocate a new one.
>
> Fixes: dfaff37fc46d ("vmxnet3: import new vmxnet3 poll mode driver implementation")
>
> Signed-off-by: Chas Williams <ciwillia at brocade.com>
> ---
>  drivers/net/vmxnet3/vmxnet3_rxtx.c | 6 +++---
>  1 file changed, 3 insertions(+), 3 deletions(-)
>
> diff --git a/drivers/net/vmxnet3/vmxnet3_rxtx.c b/drivers/net/vmxnet3/vmxnet3_rxtx.c
> index 6649c3f..104e040 100644
> --- a/drivers/net/vmxnet3/vmxnet3_rxtx.c
> +++ b/drivers/net/vmxnet3/vmxnet3_rxtx.c
> @@ -893,8 +893,8 @@ vmxnet3_recv_pkts(void *rx_queue, struct rte_mbuf **rx_pkts, uint16_t nb_pkts)
>
>  /*
>   * Create memzone for device rings. malloc can't be used as the physical address is
> - * needed. If the memzone is already created, then this function returns a ptr
> - * to the old one.
> + * needed. If the memzone already exists, we free it since it may have been created
> + * with a different size.
>   */
>  static const struct rte_memzone *
>  ring_dma_zone_reserve(struct rte_eth_dev *dev, const char *ring_name,
> @@ -909,7 +909,7 @@ ring_dma_zone_reserve(struct rte_eth_dev *dev, const char *ring_name,
>
>         mz = rte_memzone_lookup(z_name);
>         if (mz)
> -               return mz;
> +               rte_memzone_free(mz);
>
>         return rte_memzone_reserve_aligned(z_name, ring_size,
>                                            socket_id, 0, VMXNET3_RING_BA_ALIGN);

Chas,

Thanks for hunting this one down. Wouldn't the rte_memzone_free()
better fit into vmxnet3_cmd_ring_release() ?

Also the ring_dma_zone_reserve() could get replaced by
rte_eth_dma_zone_reserve() (see also
http://dpdk.org/dev/patchwork/patch/21432/).