Re: [RFC PATCH net-next 2/4] net: dsa: remove the "dsa_to_port in a loop" antipattern from the core

[Florian Fainelli <f.fainelli@gmail.com>]

On 8/9/2021 12:03 PM, Vladimir Oltean wrote:
> Ever since Vivien's conversion of the ds->ports array into a dst->ports
> list, and the introduction of dsa_to_port, iterations through the ports
> of a switch became quadratic whenever dsa_to_port was needed.
> 
> dsa_to_port can either be called directly, or indirectly through the
> dsa_is_{user,cpu,dsa,unused}_port helpers.
> 
> Introduce a basic switch port iterator macro, dsa_switch_for_each_port,
> that works with the iterator variable being a struct dsa_port *dp
> directly, and not an int i. It is an expensive variable to go from i to
> dp, but cheap to go from dp to i.
> 
> This macro iterates through the entire ds->dst->ports list and filters
> by the ports belonging just to the switch provided as argument.
> 
> While at it, provide some more flavors of that macro which filter for
> specific types of ports: at the moment just user ports and CPU ports.
> 
> Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>

Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
-- 
Florian