RTEXT_FILTER_SKIP_STATS support to avoid dumping inet/inet6 stats
Subsystems (3)
RFC PATCH 1/1 RTEXT_FILTER_SKIP_STATS support to avoid dumping inet/inet6 stats
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 comuputation for the ifinfo path.
Signed-off-by Sowmini Varadhan <[email protected]>
--- include/net/rtnetlink.h | 3 ++- include/uapi/linux/rtnetlink.h | 1 + net/core/rtnetlink.c | 3 ++- net/ipv4/devinet.c | 3 ++- net/ipv6/addrconf.c | 13 +++++++++---- 5 files changed, 16 insertions(+), 7 deletions(-)
include/net/rtnetlink.h +2 -1
@@ -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, +bool skip_af_stats);size_t (*get_link_af_size)(const struct net_device *dev); int (*validate_link_af)(const struct net_device *dev,
include/uapi/linux/rtnetlink.h +1 -0
@@ -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 */
net/core/rtnetlink.c +2 -1
@@ -1054,6 +1054,7 @@ static int rtnl_fill_ifinfo(struct sk_buff *skb, struct net_device *dev,struct nlattr *attr, *af_spec;struct rtnl_af_ops *af_ops;struct net_device *upper_dev =netdev_master_upper_dev_get (dev); +bool skip_af_stats = ((ext_filter_mask &RTEXT_FILTER_SKIP_STATS ) !=0 );ASSERT_RTNL (); nlh =nlmsg_put (skb, pid, seq, type,sizeof (*ifm), flags);
@@ -1272,7 +1273,7 @@ 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, skip_af_stats);/* * Caller may return ENODATA to indicate that there
net/ipv4/devinet.c +2 -1
@@ -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, +bool skip_af_stats) {struct in_device *in_dev =rcu_dereference_rtnl (dev->ip_ptr);struct nlattr *nla;
net/ipv6/addrconf.c +9 -4
@@ -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, +bool skip_af_stats) {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 (skip_af_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, +bool skip_af_stats) {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, skip_af_stats) <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, false) <0 ) goto nla_put_failure;nla_nest_end (skb, protoinfo);
Signature · 1 line
1.7.1
David Miller
maintainerFrom: Sowmini Varadhan <[email protected]>
Date: Thu, 10 Sep 2015 16:16:49 -0400
net/core/rtnetlink.c static int rtnl_fill_ifinfo(struct sk_buff *skb, struct net_device *dev, · line 1276
Quoted 6 lines
net/core/rtnetlink.c +1
-1@@ -1272,7 +1273,7 @@ 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, skip_af_stats);
Maybe just pass down the raw flags as 'ext_filter_mask', like we do for the rtnl_fill_ifinfo() call chain.