Re: [dpdk-dev] [PATCH] vhost: Fix retrieval of numa information in PMD

[Tetsuya Mukawa <mukawa@igel.co.jp>]

On 2016/04/06 1:09, Ciara Loftus wrote:
> After some testing, it was found that retrieving numa information
> about a vhost device via a call to get_mempolicy is more
> accurate when performed during the new_device callback versus
> the vring_state_changed callback, in particular upon initial boot
> of the VM.  Performing this check during new_device is also
> potentially more efficient as this callback is only triggered once
> during device initialisation, compared with vring_state_changed
> which may be called multiple times depending on the number of
> queues assigned to the device.
>
> Reorganise the code to perform this check and assign the correct
> socket_id to the device during the new_device callback.
>
> Signed-off-by: Ciara Loftus <ciara.loftus@intel.com>
> ---
>  drivers/net/vhost/rte_eth_vhost.c | 28 ++++++++++++++--------------
>  1 file changed, 14 insertions(+), 14 deletions(-)
>
> diff --git a/drivers/net/vhost/rte_eth_vhost.c b/drivers/net/vhost/rte_eth_vhost.c
> index 4cc6bec..b1eb082 100644
> --- a/drivers/net/vhost/rte_eth_vhost.c
> +++ b/drivers/net/vhost/rte_eth_vhost.c
>

Hi,

I appreciate fixing it.
Just one worry is that state changed event may be occurred before new
device event.
The users should not call rte_eth_dev_socket_id() until new device event
comes, even if they catch queue state events.
Otherwise, they will get wrong socket id to call
rte_eth_rx/tx_queue_setup().

So how about commenting it in 'rte_eth_vhost.h'?

Thanks,
Tetsuya