From f8ab1807a9c9aa14478920e64d1c9d3685aae26f Mon Sep 17 00:00:00 2001 From: Vlad Buslov Date: Fri, 15 May 2020 14:40:11 +0300 Subject: [PATCH] net: sched: introduce terse dump flag Add new TCA_DUMP_FLAGS attribute and use it in cls API to request terse filter output from classifiers with TCA_DUMP_FLAGS_TERSE flag. This option is intended to be used to improve performance of TC filter dump when userland only needs to obtain stats and not the whole classifier/action data. Extend struct tcf_proto_ops with new terse_dump() callback that must be defined by supporting classifier implementations. Support of the options in specific classifiers and actions is implemented in following patches in the series. Signed-off-by: Vlad Buslov Reviewed-by: Jiri Pirko Signed-off-by: David S. Miller --- include/net/sch_generic.h | 4 ++++ include/uapi/linux/rtnetlink.h | 6 ++++++ net/sched/cls_api.c | 39 +++++++++++++++++++++++++++------- 3 files changed, 41 insertions(+), 8 deletions(-) diff --git a/include/net/sch_generic.h b/include/net/sch_generic.h index ab87a8b86a32..c510b03b9751 100644 --- a/include/net/sch_generic.h +++ b/include/net/sch_generic.h @@ -330,6 +330,10 @@ struct tcf_proto_ops { int (*dump)(struct net*, struct tcf_proto*, void *, struct sk_buff *skb, struct tcmsg*, bool); + int (*terse_dump)(struct net *net, + struct tcf_proto *tp, void *fh, + struct sk_buff *skb, + struct tcmsg *t, bool rtnl_held); int (*tmplt_dump)(struct sk_buff *skb, struct net *net, void *tmplt_priv); diff --git a/include/uapi/linux/rtnetlink.h b/include/uapi/linux/rtnetlink.h index 4a8c5b745157..073e71ef6bdd 100644 --- a/include/uapi/linux/rtnetlink.h +++ b/include/uapi/linux/rtnetlink.h @@ -609,11 +609,17 @@ enum { TCA_HW_OFFLOAD, TCA_INGRESS_BLOCK, TCA_EGRESS_BLOCK, + TCA_DUMP_FLAGS, __TCA_MAX }; #define TCA_MAX (__TCA_MAX - 1) +#define TCA_DUMP_FLAGS_TERSE (1 << 0) /* Means that in dump user gets only basic + * data necessary to identify the objects + * (handle, cookie, etc.) and stats. + */ + #define TCA_RTA(r) ((struct rtattr*)(((char*)(r)) + NLMSG_ALIGN(sizeof(struct tcmsg)))) #define TCA_PAYLOAD(n) NLMSG_PAYLOAD(n,sizeof(struct tcmsg)) diff --git a/net/sched/cls_api.c b/net/sched/cls_api.c index 299b963c796e..cb2c10e0fee5 100644 --- a/net/sched/cls_api.c +++ b/net/sched/cls_api.c @@ -1851,7 +1851,7 @@ static int tcf_fill_node(struct net *net, struct sk_buff *skb, struct tcf_proto *tp, struct tcf_block *block, struct Qdisc *q, u32 parent, void *fh, u32 portid, u32 seq, u16 flags, int event, - bool rtnl_held) + bool terse_dump, bool rtnl_held) { struct tcmsg *tcm; struct nlmsghdr *nlh; @@ -1878,6 +1878,14 @@ static int tcf_fill_node(struct net *net, struct sk_buff *skb, goto nla_put_failure; if (!fh) { tcm->tcm_handle = 0; + } else if (terse_dump) { + if (tp->ops->terse_dump) { + if (tp->ops->terse_dump(net, tp, fh, skb, tcm, + rtnl_held) < 0) + goto nla_put_failure; + } else { + goto cls_op_not_supp; + } } else { if (tp->ops->dump && tp->ops->dump(net, tp, fh, skb, tcm, rtnl_held) < 0) @@ -1888,6 +1896,7 @@ static int tcf_fill_node(struct net *net, struct sk_buff *skb, out_nlmsg_trim: nla_put_failure: +cls_op_not_supp: nlmsg_trim(skb, b); return -1; } @@ -1908,7 +1917,7 @@ static int tfilter_notify(struct net *net, struct sk_buff *oskb, if (tcf_fill_node(net, skb, tp, block, q, parent, fh, portid, n->nlmsg_seq, n->nlmsg_flags, event, - rtnl_held) <= 0) { + false, rtnl_held) <= 0) { kfree_skb(skb); return -EINVAL; } @@ -1940,7 +1949,7 @@ static int tfilter_del_notify(struct net *net, struct sk_buff *oskb, if (tcf_fill_node(net, skb, tp, block, q, parent, fh, portid, n->nlmsg_seq, n->nlmsg_flags, RTM_DELTFILTER, - rtnl_held) <= 0) { + false, rtnl_held) <= 0) { NL_SET_ERR_MSG(extack, "Failed to build del event notification"); kfree_skb(skb); return -EINVAL; @@ -2501,6 +2510,7 @@ struct tcf_dump_args { struct tcf_block *block; struct Qdisc *q; u32 parent; + bool terse_dump; }; static int tcf_node_dump(struct tcf_proto *tp, void *n, struct tcf_walker *arg) @@ -2511,12 +2521,12 @@ static int tcf_node_dump(struct tcf_proto *tp, void *n, struct tcf_walker *arg) return tcf_fill_node(net, a->skb, tp, a->block, a->q, a->parent, n, NETLINK_CB(a->cb->skb).portid, a->cb->nlh->nlmsg_seq, NLM_F_MULTI, - RTM_NEWTFILTER, true); + RTM_NEWTFILTER, a->terse_dump, true); } static bool tcf_chain_dump(struct tcf_chain *chain, struct Qdisc *q, u32 parent, struct sk_buff *skb, struct netlink_callback *cb, - long index_start, long *p_index) + long index_start, long *p_index, bool terse) { struct net *net = sock_net(skb->sk); struct tcf_block *block = chain->block; @@ -2545,7 +2555,7 @@ static bool tcf_chain_dump(struct tcf_chain *chain, struct Qdisc *q, u32 parent, if (tcf_fill_node(net, skb, tp, block, q, parent, NULL, NETLINK_CB(cb->skb).portid, cb->nlh->nlmsg_seq, NLM_F_MULTI, - RTM_NEWTFILTER, true) <= 0) + RTM_NEWTFILTER, false, true) <= 0) goto errout; cb->args[1] = 1; } @@ -2561,6 +2571,7 @@ static bool tcf_chain_dump(struct tcf_chain *chain, struct Qdisc *q, u32 parent, arg.w.skip = cb->args[1] - 1; arg.w.count = 0; arg.w.cookie = cb->args[2]; + arg.terse_dump = terse; tp->ops->walk(tp, &arg.w, true); cb->args[2] = arg.w.cookie; cb->args[1] = arg.w.count + 1; @@ -2574,6 +2585,10 @@ errout: return false; } +static const struct nla_policy tcf_tfilter_dump_policy[TCA_MAX + 1] = { + [TCA_DUMP_FLAGS] = NLA_POLICY_BITFIELD32(TCA_DUMP_FLAGS_TERSE), +}; + /* called with RTNL */ static int tc_dump_tfilter(struct sk_buff *skb, struct netlink_callback *cb) { @@ -2583,6 +2598,7 @@ static int tc_dump_tfilter(struct sk_buff *skb, struct netlink_callback *cb) struct Qdisc *q = NULL; struct tcf_block *block; struct tcmsg *tcm = nlmsg_data(cb->nlh); + bool terse_dump = false; long index_start; long index; u32 parent; @@ -2592,10 +2608,17 @@ static int tc_dump_tfilter(struct sk_buff *skb, struct netlink_callback *cb) return skb->len; err = nlmsg_parse_deprecated(cb->nlh, sizeof(*tcm), tca, TCA_MAX, - NULL, cb->extack); + tcf_tfilter_dump_policy, cb->extack); if (err) return err; + if (tca[TCA_DUMP_FLAGS]) { + struct nla_bitfield32 flags = + nla_get_bitfield32(tca[TCA_DUMP_FLAGS]); + + terse_dump = flags.value & TCA_DUMP_FLAGS_TERSE; + } + if (tcm->tcm_ifindex == TCM_IFINDEX_MAGIC_BLOCK) { block = tcf_block_refcnt_get(net, tcm->tcm_block_index); if (!block) @@ -2653,7 +2676,7 @@ static int tc_dump_tfilter(struct sk_buff *skb, struct netlink_callback *cb) nla_get_u32(tca[TCA_CHAIN]) != chain->index) continue; if (!tcf_chain_dump(chain, q, parent, skb, cb, - index_start, &index)) { + index_start, &index, terse_dump)) { tcf_chain_put(chain); err = -EMSGSIZE; break;