Commit b2c8599f authored by Jakub Kicinski's avatar Jakub Kicinski
Browse files

Merge branch 'netdev-support-dumping-a-single-netdev-in-qstats' 

Jakub Kicinski says:

====================
netdev: support dumping a single netdev in qstats

I was writing a test for page pool which depended on qstats,
and got tired of having to filter dumps in user space.
Add support for dumping stats for a single netdev.

To get there we first need to add full support for extack
in dumps (and fix a dump error handling bug in YNL, sent
separately to the net tree).
====================

Link: https://lore.kernel.org/r/20240420023543.3300306-1-kuba@kernel.org


Signed-off-by: default avatarJakub Kicinski <kuba@kernel.org>
parents 1af2dfac 23710925

Documentation/netlink/specs/netdev.yaml

+1 −0
Original line number Diff line number Diff line
@@ -486,6 +486,7 @@ operations: 
      dump:

        request:

          attributes:

            - ifindex

            - scope

        reply:

          attributes:

net/core/netdev-genl-gen.c

+1 −0
Original line number Diff line number Diff line
@@ -70,6 +70,7 @@ static const struct nla_policy netdev_napi_get_dump_nl_policy[NETDEV_A_NAPI_IFIN 


/* NETDEV_CMD_QSTATS_GET - dump */

static const struct nla_policy netdev_qstats_get_nl_policy[NETDEV_A_QSTATS_SCOPE + 1] = {

	[NETDEV_A_QSTATS_IFINDEX] = NLA_POLICY_MIN(NLA_U32, 1),

	[NETDEV_A_QSTATS_SCOPE] = NLA_POLICY_MASK(NLA_UINT, 0x1),

};

net/core/netdev-genl.c

+39 −13
Original line number Diff line number Diff line
@@ -639,6 +639,24 @@ netdev_nl_stats_by_netdev(struct net_device *netdev, struct sk_buff *rsp, 
	return -EMSGSIZE;

}



static int

netdev_nl_qstats_get_dump_one(struct net_device *netdev, unsigned int scope,

			      struct sk_buff *skb, const struct genl_info *info,

			      struct netdev_nl_dump_ctx *ctx)

{

	if (!netdev->stat_ops)

		return 0;



	switch (scope) {

	case 0:

		return netdev_nl_stats_by_netdev(netdev, skb, info);

	case NETDEV_QSTATS_SCOPE_QUEUE:

		return netdev_nl_stats_by_queue(netdev, skb, info, ctx);

	}



	return -EINVAL;	/* Should not happen, per netlink policy */

}



int netdev_nl_qstats_get_dumpit(struct sk_buff *skb,

				struct netlink_callback *cb)

{
@@ -646,6 +664,7 @@ int netdev_nl_qstats_get_dumpit(struct sk_buff *skb, 
	const struct genl_info *info = genl_info_dump(cb);

	struct net *net = sock_net(skb->sk);

	struct net_device *netdev;

	unsigned int ifindex;

	unsigned int scope;

	int err = 0;
@@ -653,22 +672,29 @@ int netdev_nl_qstats_get_dumpit(struct sk_buff *skb, 
	if (info->attrs[NETDEV_A_QSTATS_SCOPE])

		scope = nla_get_uint(info->attrs[NETDEV_A_QSTATS_SCOPE]);



	rtnl_lock();

	for_each_netdev_dump(net, netdev, ctx->ifindex) {

		if (!netdev->stat_ops)

			continue;

	ifindex = 0;

	if (info->attrs[NETDEV_A_QSTATS_IFINDEX])

		ifindex = nla_get_u32(info->attrs[NETDEV_A_QSTATS_IFINDEX]);



		switch (scope) {

		case 0:

			err = netdev_nl_stats_by_netdev(netdev, skb, info);

			break;

		case NETDEV_QSTATS_SCOPE_QUEUE:

			err = netdev_nl_stats_by_queue(netdev, skb, info, ctx);

			break;

	rtnl_lock();

	if (ifindex) {

		netdev = __dev_get_by_index(net, ifindex);

		if (netdev && netdev->stat_ops) {

			err = netdev_nl_qstats_get_dump_one(netdev, scope, skb,

							    info, ctx);

		} else {

			NL_SET_BAD_ATTR(info->extack,

					info->attrs[NETDEV_A_QSTATS_IFINDEX]);

			err = netdev ? -EOPNOTSUPP : -ENODEV;

		}

	} else {

		for_each_netdev_dump(net, netdev, ctx->ifindex) {

			err = netdev_nl_qstats_get_dump_one(netdev, scope, skb,

							    info, ctx);

			if (err < 0)

				break;

		}

	}

	rtnl_unlock();



	return err;

net/netlink/af_netlink.c

+70 −65
Original line number Diff line number Diff line
@@ -2165,6 +2165,69 @@ __nlmsg_put(struct sk_buff *skb, u32 portid, u32 seq, int type, int len, int fla 
}

EXPORT_SYMBOL(__nlmsg_put);



static size_t

netlink_ack_tlv_len(struct netlink_sock *nlk, int err,

		    const struct netlink_ext_ack *extack)

{

	size_t tlvlen;



	if (!extack || !test_bit(NETLINK_F_EXT_ACK, &nlk->flags))

		return 0;



	tlvlen = 0;

	if (extack->_msg)

		tlvlen += nla_total_size(strlen(extack->_msg) + 1);

	if (extack->cookie_len)

		tlvlen += nla_total_size(extack->cookie_len);



	/* Following attributes are only reported as error (not warning) */

	if (!err)

		return tlvlen;



	if (extack->bad_attr)

		tlvlen += nla_total_size(sizeof(u32));

	if (extack->policy)

		tlvlen += netlink_policy_dump_attr_size_estimate(extack->policy);

	if (extack->miss_type)

		tlvlen += nla_total_size(sizeof(u32));

	if (extack->miss_nest)

		tlvlen += nla_total_size(sizeof(u32));



	return tlvlen;

}



static void

netlink_ack_tlv_fill(struct sk_buff *in_skb, struct sk_buff *skb,

		     const struct nlmsghdr *nlh, int err,

		     const struct netlink_ext_ack *extack)

{

	if (extack->_msg)

		WARN_ON(nla_put_string(skb, NLMSGERR_ATTR_MSG, extack->_msg));

	if (extack->cookie_len)

		WARN_ON(nla_put(skb, NLMSGERR_ATTR_COOKIE,

				extack->cookie_len, extack->cookie));



	if (!err)

		return;



	if (extack->bad_attr &&

	    !WARN_ON((u8 *)extack->bad_attr < in_skb->data ||

		     (u8 *)extack->bad_attr >= in_skb->data + in_skb->len))

		WARN_ON(nla_put_u32(skb, NLMSGERR_ATTR_OFFS,

				    (u8 *)extack->bad_attr - (const u8 *)nlh));

	if (extack->policy)

		netlink_policy_dump_write_attr(skb, extack->policy,

					       NLMSGERR_ATTR_POLICY);

	if (extack->miss_type)

		WARN_ON(nla_put_u32(skb, NLMSGERR_ATTR_MISS_TYPE,

				    extack->miss_type));

	if (extack->miss_nest &&

	    !WARN_ON((u8 *)extack->miss_nest < in_skb->data ||

		     (u8 *)extack->miss_nest > in_skb->data + in_skb->len))

		WARN_ON(nla_put_u32(skb, NLMSGERR_ATTR_MISS_NEST,

				    (u8 *)extack->miss_nest - (const u8 *)nlh));

}



/*

 * It looks a bit ugly.

 * It would be better to create kernel thread.
@@ -2175,6 +2238,7 @@ static int netlink_dump_done(struct netlink_sock *nlk, struct sk_buff *skb, 
			     struct netlink_ext_ack *extack)

{

	struct nlmsghdr *nlh;

	size_t extack_len;



	nlh = nlmsg_put_answer(skb, cb, NLMSG_DONE, sizeof(nlk->dump_done_errno),

			       NLM_F_MULTI | cb->answer_flags);
@@ -2184,11 +2248,15 @@ static int netlink_dump_done(struct netlink_sock *nlk, struct sk_buff *skb, 
	nl_dump_check_consistent(cb, nlh);

	memcpy(nlmsg_data(nlh), &nlk->dump_done_errno, sizeof(nlk->dump_done_errno));



	if (extack->_msg && test_bit(NETLINK_F_EXT_ACK, &nlk->flags)) {

	extack_len = netlink_ack_tlv_len(nlk, nlk->dump_done_errno, extack);

	if (extack_len) {

		nlh->nlmsg_flags |= NLM_F_ACK_TLVS;

		if (!nla_put_string(skb, NLMSGERR_ATTR_MSG, extack->_msg))

		if (skb_tailroom(skb) >= extack_len) {

			netlink_ack_tlv_fill(cb->skb, skb, cb->nlh,

					     nlk->dump_done_errno, extack);

			nlmsg_end(skb, nlh);

		}

	}



	return 0;

}
@@ -2406,69 +2474,6 @@ int __netlink_dump_start(struct sock *ssk, struct sk_buff *skb, 
}

EXPORT_SYMBOL(__netlink_dump_start);



static size_t

netlink_ack_tlv_len(struct netlink_sock *nlk, int err,

		    const struct netlink_ext_ack *extack)

{

	size_t tlvlen;



	if (!extack || !test_bit(NETLINK_F_EXT_ACK, &nlk->flags))

		return 0;



	tlvlen = 0;

	if (extack->_msg)

		tlvlen += nla_total_size(strlen(extack->_msg) + 1);

	if (extack->cookie_len)

		tlvlen += nla_total_size(extack->cookie_len);



	/* Following attributes are only reported as error (not warning) */

	if (!err)

		return tlvlen;



	if (extack->bad_attr)

		tlvlen += nla_total_size(sizeof(u32));

	if (extack->policy)

		tlvlen += netlink_policy_dump_attr_size_estimate(extack->policy);

	if (extack->miss_type)

		tlvlen += nla_total_size(sizeof(u32));

	if (extack->miss_nest)

		tlvlen += nla_total_size(sizeof(u32));



	return tlvlen;

}



static void

netlink_ack_tlv_fill(struct sk_buff *in_skb, struct sk_buff *skb,

		     struct nlmsghdr *nlh, int err,

		     const struct netlink_ext_ack *extack)

{

	if (extack->_msg)

		WARN_ON(nla_put_string(skb, NLMSGERR_ATTR_MSG, extack->_msg));

	if (extack->cookie_len)

		WARN_ON(nla_put(skb, NLMSGERR_ATTR_COOKIE,

				extack->cookie_len, extack->cookie));



	if (!err)

		return;



	if (extack->bad_attr &&

	    !WARN_ON((u8 *)extack->bad_attr < in_skb->data ||

		     (u8 *)extack->bad_attr >= in_skb->data + in_skb->len))

		WARN_ON(nla_put_u32(skb, NLMSGERR_ATTR_OFFS,

				    (u8 *)extack->bad_attr - (u8 *)nlh));

	if (extack->policy)

		netlink_policy_dump_write_attr(skb, extack->policy,

					       NLMSGERR_ATTR_POLICY);

	if (extack->miss_type)

		WARN_ON(nla_put_u32(skb, NLMSGERR_ATTR_MISS_TYPE,

				    extack->miss_type));

	if (extack->miss_nest &&

	    !WARN_ON((u8 *)extack->miss_nest < in_skb->data ||

		     (u8 *)extack->miss_nest > in_skb->data + in_skb->len))

		WARN_ON(nla_put_u32(skb, NLMSGERR_ATTR_MISS_NEST,

				    (u8 *)extack->miss_nest - (u8 *)nlh));

}



void netlink_ack(struct sk_buff *in_skb, struct nlmsghdr *nlh, int err,

		 const struct netlink_ext_ack *extack)

{

tools/testing/selftests/drivers/net/stats.py

+59 −3
Original line number Diff line number Diff line 
#!/usr/bin/env python3

# SPDX-License-Identifier: GPL-2.0



from lib.py import ksft_run, ksft_exit

from lib.py import ksft_in, ksft_true, KsftSkipEx, KsftXfailEx

from lib.py import ksft_run, ksft_exit, ksft_pr

from lib.py import ksft_ge, ksft_eq, ksft_in, ksft_true, ksft_raises, KsftSkipEx, KsftXfailEx

from lib.py import EthtoolFamily, NetdevFamily, RtnlFamily, NlError

from lib.py import NetDrvEnv
@@ -77,9 +77,65 @@ def pkt_byte_sum(cfg) -> None: 
            raise Exception("Qstats are lower, fetched later")





def qstat_by_ifindex(cfg) -> None:

    global netfam

    global rtnl



    # Construct a map ifindex -> [dump, by-index, dump]

    ifindexes = {}

    stats = netfam.qstats_get({}, dump=True)

    for entry in stats:

        ifindexes[entry['ifindex']] = [entry, None, None]



    for ifindex in ifindexes.keys():

        entry = netfam.qstats_get({"ifindex": ifindex}, dump=True)

        ksft_eq(len(entry), 1)

        ifindexes[entry[0]['ifindex']][1] = entry[0]



    stats = netfam.qstats_get({}, dump=True)

    for entry in stats:

        ifindexes[entry['ifindex']][2] = entry



    if len(ifindexes) == 0:

        raise KsftSkipEx("No ifindex supports qstats")



    # Now make sure the stats match/make sense

    for ifindex, triple in ifindexes.items():

        all_keys = triple[0].keys() | triple[1].keys() | triple[2].keys()



        for key in all_keys:

            ksft_ge(triple[1][key], triple[0][key], comment="bad key: " + key)

            ksft_ge(triple[2][key], triple[1][key], comment="bad key: " + key)



    # Test invalid dumps

    # 0 is invalid

    with ksft_raises(NlError) as cm:

        netfam.qstats_get({"ifindex": 0}, dump=True)

    ksft_eq(cm.exception.nl_msg.error, -34)

    ksft_eq(cm.exception.nl_msg.extack['bad-attr'], '.ifindex')



    # loopback has no stats

    with ksft_raises(NlError) as cm:

        netfam.qstats_get({"ifindex": 1}, dump=True)

    ksft_eq(cm.exception.nl_msg.error, -95)

    ksft_eq(cm.exception.nl_msg.extack['bad-attr'], '.ifindex')



    # Try to get stats for lowest unused ifindex but not 0

    devs = rtnl.getlink({}, dump=True)

    all_ifindexes = set([dev["ifi-index"] for dev in devs])

    lowest = 2

    while lowest in all_ifindexes:

        lowest += 1



    with ksft_raises(NlError) as cm:

        netfam.qstats_get({"ifindex": lowest}, dump=True)

    ksft_eq(cm.exception.nl_msg.error, -19)

    ksft_eq(cm.exception.nl_msg.extack['bad-attr'], '.ifindex')





def main() -> None:

    with NetDrvEnv(__file__) as cfg:

        ksft_run([check_pause, check_fec, pkt_byte_sum],

        ksft_run([check_pause, check_fec, pkt_byte_sum, qstat_by_ifindex],

                 args=(cfg, ))

    ksft_exit()