Commit 735d381f authored by Jiri Pirko's avatar Jiri Pirko Committed by David S. Miller
Browse files

team: remove synchronize_rcu() called during port disable 



Check the unlikely case of team->en_port_count == 0 before modulo
operation.

Signed-off-by: default avatarJiri Pirko <jiri@resnulli.us>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent d80b35be

drivers/net/team/team.c

+5 −15
Original line number Diff line number Diff line
@@ -525,31 +525,26 @@ static void team_set_no_mode(struct team *team) 
	team->mode = &__team_no_mode;

}



static void __team_adjust_ops(struct team *team, int en_port_count)

static void team_adjust_ops(struct team *team)

{

	/*

	 * To avoid checks in rx/tx skb paths, ensure here that non-null and

	 * correct ops are always set.

	 */



	if (!en_port_count || !team_is_mode_set(team) ||

	if (!team->en_port_count || !team_is_mode_set(team) ||

	    !team->mode->ops->transmit)

		team->ops.transmit = team_dummy_transmit;

	else

		team->ops.transmit = team->mode->ops->transmit;



	if (!en_port_count || !team_is_mode_set(team) ||

	if (!team->en_port_count || !team_is_mode_set(team) ||

	    !team->mode->ops->receive)

		team->ops.receive = team_dummy_receive;

	else

		team->ops.receive = team->mode->ops->receive;

}



static void team_adjust_ops(struct team *team)

{

	__team_adjust_ops(team, team->en_port_count);

}



/*

 * We can benefit from the fact that it's ensured no port is present

 * at the time of mode change. Therefore no packets are in fly so there's no
@@ -877,14 +872,9 @@ static void team_port_disable(struct team *team, 
	hlist_del_rcu(&port->hlist);

	__reconstruct_port_hlist(team, port->index);

	port->index = -1;

	team_queue_override_port_del(team, port);

	__team_adjust_ops(team, team->en_port_count - 1);

	/*

	 * Wait until readers see adjusted ops. This ensures that

	 * readers never see team->en_port_count == 0

	 */

	synchronize_rcu();

	team->en_port_count--;

	team_queue_override_port_del(team, port);

	team_adjust_ops(team);

}



#define TEAM_VLAN_FEATURES (NETIF_F_ALL_CSUM | NETIF_F_SG | \

drivers/net/team/team_mode_loadbalance.c

+1 −2
Original line number Diff line number Diff line
@@ -112,9 +112,8 @@ static struct team_port *lb_hash_select_tx_port(struct team *team, 
						struct sk_buff *skb,

						unsigned char hash)

{

	int port_index;

	int port_index = team_num_to_port_index(team, hash);



	port_index = hash % team->en_port_count;

	return team_get_port_by_index_rcu(team, port_index);

}

drivers/net/team/team_mode_roundrobin.c

+2 −1
Original line number Diff line number Diff line
@@ -30,7 +30,8 @@ static bool rr_transmit(struct team *team, struct sk_buff *skb) 
	struct team_port *port;

	int port_index;



	port_index = rr_priv(team)->sent_packets++ % team->en_port_count;

	port_index = team_num_to_port_index(team,

					    rr_priv(team)->sent_packets++);

	port = team_get_port_by_index_rcu(team, port_index);

	port = team_get_first_port_txable_rcu(team, port);

	if (unlikely(!port))

include/linux/if_team.h

+10 −0
Original line number Diff line number Diff line
@@ -229,6 +229,16 @@ static inline struct team_port *team_get_port_by_index(struct team *team, 
			return port;

	return NULL;

}



static inline int team_num_to_port_index(struct team *team, int num)

{

	int en_port_count = ACCESS_ONCE(team->en_port_count);



	if (unlikely(!en_port_count))

		return 0;

	return num % en_port_count;

}



static inline struct team_port *team_get_port_by_index_rcu(struct team *team,

							   int port_index)

{