Commit 82b31898 authored by Vladimir Oltean's avatar Vladimir Oltean Committed by David S. Miller
Browse files

net: dsa: introduce helpers for iterating through ports using dp 



Since the DSA conversion from the ds->ports array into the dst->ports
list, the DSA API has encouraged driver writers, as well as the core
itself, to write inefficient code.

Currently, code that wants to filter by a specific type of port when
iterating, like {!unused, user, cpu, dsa}, uses the dsa_is_*_port helper.
Under the hood, this uses dsa_to_port which iterates again through
dst->ports. But the driver iterates through the port list already, so
the complexity is quadratic for the typical case of a single-switch
tree.

This patch introduces some iteration helpers where the iterator is
already a struct dsa_port *dp, so that the other variant of the
filtering functions, dsa_port_is_{unused,user,cpu_dsa}, can be used
directly on the iterator. This eliminates the second lookup.

These functions can be used both by the core and by drivers.

Signed-off-by: default avatarVladimir Oltean <vladimir.oltean@nxp.com>
Reviewed-by: default avatarFlorian Fainelli <f.fainelli@gmail.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent dedb0809

include/net/dsa.h

+28 −0
Original line number Diff line number Diff line
@@ -474,6 +474,34 @@ static inline bool dsa_is_user_port(struct dsa_switch *ds, int p) 
	return dsa_to_port(ds, p)->type == DSA_PORT_TYPE_USER;

}



#define dsa_tree_for_each_user_port(_dp, _dst) \

	list_for_each_entry((_dp), &(_dst)->ports, list) \

		if (dsa_port_is_user((_dp)))



#define dsa_switch_for_each_port(_dp, _ds) \

	list_for_each_entry((_dp), &(_ds)->dst->ports, list) \

		if ((_dp)->ds == (_ds))



#define dsa_switch_for_each_port_safe(_dp, _next, _ds) \

	list_for_each_entry_safe((_dp), (_next), &(_ds)->dst->ports, list) \

		if ((_dp)->ds == (_ds))



#define dsa_switch_for_each_port_continue_reverse(_dp, _ds) \

	list_for_each_entry_continue_reverse((_dp), &(_ds)->dst->ports, list) \

		if ((_dp)->ds == (_ds))



#define dsa_switch_for_each_available_port(_dp, _ds) \

	dsa_switch_for_each_port((_dp), (_ds)) \

		if (!dsa_port_is_unused((_dp)))



#define dsa_switch_for_each_user_port(_dp, _ds) \

	dsa_switch_for_each_port((_dp), (_ds)) \

		if (dsa_port_is_user((_dp)))



#define dsa_switch_for_each_cpu_port(_dp, _ds) \

	dsa_switch_for_each_port((_dp), (_ds)) \

		if (dsa_port_is_cpu((_dp)))



static inline u32 dsa_user_ports(struct dsa_switch *ds)

{

	u32 mask = 0;