[dpdk-stable] [PATCH v2] net/mlx5: fix link status query

[Shahaf Shuler]

: Tuesday, January 31, 2017 6:17 PM, Ferruh Yigit:
> On 1/31/2017 11:45 AM, Shahaf Shuler wrote:
> > Trying to query the link status through new kernel ioctl API
> > ETHTOOL_GLINKSETTINGS was always failing due to kernel bug.
> > The bug was fixed on version 4.9
> > this patch uses the legacy ioctl API for lower kernels.
> >
> > Fixes: 188408719888 ("net/mlx5: fix support for newer link speeds")
> > CC: stable at dpdk.org
> >
> > Signed-off-by: Shahaf Shuler <shahafs at mellanox.com>
> > ---
> 
> <...>
> 
> > @@ -707,7 +708,7 @@ struct priv *
> >  static int
> >  mlx5_link_update_unlocked_gs(struct rte_eth_dev *dev, int
> > wait_to_complete)  { -#ifdef ETHTOOL_GLINKSETTINGS
> > +#if KERNEL_VERSION(4, 9, 0) <= LINUX_VERSION_CODE
> 
> Mostly it is not good idea to do kernel version check in the .c file.
> 
> It is possible to move this comparison to the .h file, and set a feature
> macro based on comparison result, like HAVE_ETHTOOL_GLINKSETTINGS,
> and
> use this macro in the .c file.
> 
> This makes .c code easier to understand. And the abstraction in the
> header file lets you update the comparison in the future without
> changing the code itself.
> 
> But it is your call, do you prefer to continue with this one?

This is a good suggestion. 
Adrien, Nélio what do you think?

> 
> >  	struct priv *priv = mlx5_get_priv(dev);
> >  	struct ethtool_link_settings edata = {
> >  		.cmd = ETHTOOL_GLINKSETTINGS,
> <...>