Subject: Re: [PATCH net-next v2] net: sysfs: Do not create sysfs for non BQL device

From: Stephen Hemminger <[email-masked]>
Date: Fri, 16 Feb 2024 09:29:05 -0800

On Fri, 16 Feb 2024 01:41:52 -0800
Breno Leitao <[email-masked]> wrote:

> +static bool netdev_uses_bql(const struct net_device *dev)
> +{
> +	if (dev->features & NETIF_F_LLTX ||
> +	    dev->priv_flags & IFF_NO_QUEUE)
> +		return false;
> +
> +	return IS_ENABLED(CONFIG_BQL);
> +}

Various compilers will warn about missing parens in that expression.
It is valid but mixing & and || can be bug trap.

	if ((dev->features & NETIF_F_LLTX) || (dev->priv_flags & IFF_NO_QUEUE))
		return false;

Not all drivers will be using bql, it requires driver to have that code.
So really it means driver could be using BQL.
Not sure if there is a way to find out if driver has the required BQL bits.