Commit 9eb43e76 authored by Eric Dumazet's avatar Eric Dumazet Committed by David S. Miller
Browse files

ipv4: Introduce IN_DEV_NET_ROUTE_LOCALNET 



performance profiles show a high cost in the IN_DEV_ROUTE_LOCALNET()
call done in ip_route_input_slow(), because of multiple dereferences,
even if cache lines are clean and available in cpu caches.

Since we already have the 'net' pointer, introduce
IN_DEV_NET_ROUTE_LOCALNET() macro avoiding two dereferences
(dev_net(in_dev->dev))

Also change the tests to use IN_DEV_NET_ROUTE_LOCALNET() only if saddr
or/and daddr are loopback addresse.

Signed-off-by: default avatarEric Dumazet <edumazet@google.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent 40384999

include/linux/inetdevice.h

+9 −2
Original line number Original line Diff line number Diff line
@@ -104,9 +104,14 @@ static inline void ipv4_devconf_setall(struct in_device *in_dev) 
#define IN_DEV_ANDCONF(in_dev, attr) \

#define IN_DEV_ANDCONF(in_dev, attr) \

	(IPV4_DEVCONF_ALL(dev_net(in_dev->dev), attr) && \

	(IPV4_DEVCONF_ALL(dev_net(in_dev->dev), attr) && \

	 IN_DEV_CONF_GET((in_dev), attr))

	 IN_DEV_CONF_GET((in_dev), attr))

#define IN_DEV_ORCONF(in_dev, attr) \



	(IPV4_DEVCONF_ALL(dev_net(in_dev->dev), attr) || \

#define IN_DEV_NET_ORCONF(in_dev, net, attr) \

	(IPV4_DEVCONF_ALL(net, attr) || \

	 IN_DEV_CONF_GET((in_dev), attr))

	 IN_DEV_CONF_GET((in_dev), attr))



#define IN_DEV_ORCONF(in_dev, attr) \

	IN_DEV_NET_ORCONF(in_dev, dev_net(in_dev->dev), attr)



#define IN_DEV_MAXCONF(in_dev, attr) \

#define IN_DEV_MAXCONF(in_dev, attr) \

	(max(IPV4_DEVCONF_ALL(dev_net(in_dev->dev), attr), \

	(max(IPV4_DEVCONF_ALL(dev_net(in_dev->dev), attr), \

	     IN_DEV_CONF_GET((in_dev), attr)))

	     IN_DEV_CONF_GET((in_dev), attr)))
@@ -133,6 +138,8 @@ static inline void ipv4_devconf_setall(struct in_device *in_dev) 
					IN_DEV_ORCONF((in_dev), \

					IN_DEV_ORCONF((in_dev), \

						      PROMOTE_SECONDARIES)

						      PROMOTE_SECONDARIES)

#define IN_DEV_ROUTE_LOCALNET(in_dev)	IN_DEV_ORCONF(in_dev, ROUTE_LOCALNET)

#define IN_DEV_ROUTE_LOCALNET(in_dev)	IN_DEV_ORCONF(in_dev, ROUTE_LOCALNET)

#define IN_DEV_NET_ROUTE_LOCALNET(in_dev, net)	\

	IN_DEV_NET_ORCONF(in_dev, net, ROUTE_LOCALNET)





#define IN_DEV_RX_REDIRECTS(in_dev) \

#define IN_DEV_RX_REDIRECTS(in_dev) \

	((IN_DEV_FORWARD(in_dev) && \

	((IN_DEV_FORWARD(in_dev) && \

net/ipv4/route.c

+7 −4
Original line number Original line Diff line number Diff line
@@ -1587,11 +1587,14 @@ static int ip_route_input_slow(struct sk_buff *skb, __be32 daddr, __be32 saddr, 
	if (ipv4_is_zeronet(daddr))

	if (ipv4_is_zeronet(daddr))

		goto martian_destination;

		goto martian_destination;





	if (likely(!IN_DEV_ROUTE_LOCALNET(in_dev))) {

	/* Following code try to avoid calling IN_DEV_NET_ROUTE_LOCALNET(),

		if (ipv4_is_loopback(daddr))

	 * and call it once if daddr or/and saddr are loopback addresses

	 */

	if (ipv4_is_loopback(daddr)) {

		if (!IN_DEV_NET_ROUTE_LOCALNET(in_dev, net))

			goto martian_destination;

			goto martian_destination;



	} else if (ipv4_is_loopback(saddr)) {

		if (ipv4_is_loopback(saddr))

		if (!IN_DEV_NET_ROUTE_LOCALNET(in_dev, net))

			goto martian_source;

			goto martian_source;

	}

	}

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