Many commonly used functions like getifaddrs() invoke RTM_GETLINK to dump the interface information, and do not need the the AF_INET6 statististics that are always returned by default from rtnl_fill_ifinfo().
Computing the statistics can be an expensive operation that impacts scaling, so it is desirable to avoid this if the information is not needed. This patch adds a the RTEXT_FILTER_SKIP_STATS extended info flag that can be passed with netlink_request() to avoid statistics computation for the ifinfo path. Signed-off-by: Sowmini Varadhan <sowmini.varad...@oracle.com> --- v2: David Miller comments: pass u32 ext_filter_mask down. include/net/rtnetlink.h | 3 ++- include/uapi/linux/rtnetlink.h | 1 + net/core/rtnetlink.c | 2 +- net/ipv4/devinet.c | 3 ++- net/ipv6/addrconf.c | 13 +++++++++---- 5 files changed, 15 insertions(+), 7 deletions(-) diff --git a/include/net/rtnetlink.h b/include/net/rtnetlink.h index 18fdb98..aff6ceb 100644 --- a/include/net/rtnetlink.h +++ b/include/net/rtnetlink.h @@ -122,7 +122,8 @@ struct rtnl_af_ops { int family; int (*fill_link_af)(struct sk_buff *skb, - const struct net_device *dev); + const struct net_device *dev, + u32 ext_filter_mask); size_t (*get_link_af_size)(const struct net_device *dev); int (*validate_link_af)(const struct net_device *dev, diff --git a/include/uapi/linux/rtnetlink.h b/include/uapi/linux/rtnetlink.h index 7020247..434227f 100644 --- a/include/uapi/linux/rtnetlink.h +++ b/include/uapi/linux/rtnetlink.h @@ -666,6 +666,7 @@ struct tcamsg { #define RTEXT_FILTER_VF (1 << 0) #define RTEXT_FILTER_BRVLAN (1 << 1) #define RTEXT_FILTER_BRVLAN_COMPRESSED (1 << 2) +#define RTEXT_FILTER_SKIP_STATS (1 << 3) /* End of information exported to user level */ diff --git a/net/core/rtnetlink.c b/net/core/rtnetlink.c index a466821..e545229 100644 --- a/net/core/rtnetlink.c +++ b/net/core/rtnetlink.c @@ -1272,7 +1272,7 @@ static int rtnl_fill_ifinfo(struct sk_buff *skb, struct net_device *dev, if (!(af = nla_nest_start(skb, af_ops->family))) goto nla_put_failure; - err = af_ops->fill_link_af(skb, dev); + err = af_ops->fill_link_af(skb, dev, ext_filter_mask); /* * Caller may return ENODATA to indicate that there diff --git a/net/ipv4/devinet.c b/net/ipv4/devinet.c index 2d9cb17..7350084 100644 --- a/net/ipv4/devinet.c +++ b/net/ipv4/devinet.c @@ -1654,7 +1654,8 @@ static size_t inet_get_link_af_size(const struct net_device *dev) return nla_total_size(IPV4_DEVCONF_MAX * 4); /* IFLA_INET_CONF */ } -static int inet_fill_link_af(struct sk_buff *skb, const struct net_device *dev) +static int inet_fill_link_af(struct sk_buff *skb, const struct net_device *dev, + u32 ext_filter_mask) { struct in_device *in_dev = rcu_dereference_rtnl(dev->ip_ptr); struct nlattr *nla; diff --git a/net/ipv6/addrconf.c b/net/ipv6/addrconf.c index 99c0f2b..9acbb09 100644 --- a/net/ipv6/addrconf.c +++ b/net/ipv6/addrconf.c @@ -4760,7 +4760,8 @@ static void snmp6_fill_stats(u64 *stats, struct inet6_dev *idev, int attrtype, } } -static int inet6_fill_ifla6_attrs(struct sk_buff *skb, struct inet6_dev *idev) +static int inet6_fill_ifla6_attrs(struct sk_buff *skb, struct inet6_dev *idev, + u32 ext_filter_mask) { struct nlattr *nla; struct ifla_cacheinfo ci; @@ -4780,6 +4781,9 @@ static int inet6_fill_ifla6_attrs(struct sk_buff *skb, struct inet6_dev *idev) /* XXX - MC not implemented */ + if (!!(ext_filter_mask & RTEXT_FILTER_SKIP_STATS)) + return 0; + nla = nla_reserve(skb, IFLA_INET6_STATS, IPSTATS_MIB_MAX * sizeof(u64)); if (!nla) goto nla_put_failure; @@ -4815,14 +4819,15 @@ static size_t inet6_get_link_af_size(const struct net_device *dev) return inet6_ifla6_size(); } -static int inet6_fill_link_af(struct sk_buff *skb, const struct net_device *dev) +static int inet6_fill_link_af(struct sk_buff *skb, const struct net_device *dev, + u32 ext_filter_mask) { struct inet6_dev *idev = __in6_dev_get(dev); if (!idev) return -ENODATA; - if (inet6_fill_ifla6_attrs(skb, idev) < 0) + if (inet6_fill_ifla6_attrs(skb, idev, ext_filter_mask) < 0) return -EMSGSIZE; return 0; @@ -4977,7 +4982,7 @@ static int inet6_fill_ifinfo(struct sk_buff *skb, struct inet6_dev *idev, if (!protoinfo) goto nla_put_failure; - if (inet6_fill_ifla6_attrs(skb, idev) < 0) + if (inet6_fill_ifla6_attrs(skb, idev, 0) < 0) goto nla_put_failure; nla_nest_end(skb, protoinfo); -- 1.7.1 -- To unsubscribe from this list: send the line "unsubscribe netdev" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html