From mboxrd@z Thu Jan 1 00:00:00 1970 From: Zhu Yanjun Subject: [PATCH for kernel 3.4.x 1/1] net: neighbour: Add mcast_resolicit to configure the number of multicast resolicitations in PROBE state Date: Tue, 24 Mar 2015 17:45:55 +0800 Message-ID: <1427190355-1216-2-git-send-email-Yanjun.Zhu@windriver.com> References: <1427190355-1216-1-git-send-email-Yanjun.Zhu@windriver.com> Mime-Version: 1.0 Content-Type: text/plain To: , , , , , Return-path: Received: from mail1.windriver.com ([147.11.146.13]:44596 "EHLO mail1.windriver.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752042AbbCXJpr (ORCPT ); Tue, 24 Mar 2015 05:45:47 -0400 In-Reply-To: <1427190355-1216-1-git-send-email-Yanjun.Zhu@windriver.com> Sender: netdev-owner@vger.kernel.org List-ID: We send unicast neighbor (ARP or NDP) solicitations ucast_probes times in PROBE state. Zhu Yanjun reported that some implementation does not reply against them and the entry will become FAILED, which is undesirable. We had been dealt with such nodes by sending multicast probes mcast_ solicit times after unicast probes in PROBE state. In 2003, I made a change not to send them to improve compatibility with IPv6 NDP. Let's introduce per-protocol per-interface sysctl knob "mcast_ reprobe" to configure the number of multicast (re)solicitation for reconfirmation in PROBE state. The default is 0, since we have been doing so for 10+ years. Reported-by: Zhu Yanjun CC: Ulf Samuelsson Signed-off-by: YOSHIFUJI Hideaki Signed-off-by: YOSHIFUJI Hideaki [Zhu Yanjun: since kernel 3.4.x is different from mainline kernel(kernel 4.0-rcX). This patch is modified a lot.] Signed-off-by: Zhu Yanjun --- include/linux/neighbour.h | 1 + include/net/neighbour.h | 1 + net/core/neighbour.c | 20 +++++++++++++++++--- 3 files changed, 19 insertions(+), 3 deletions(-) diff --git a/include/linux/neighbour.h b/include/linux/neighbour.h index b188f68..6945f4f 100644 --- a/include/linux/neighbour.h +++ b/include/linux/neighbour.h @@ -112,6 +112,7 @@ enum { NDTPA_APP_PROBES, /* u32 */ NDTPA_UCAST_PROBES, /* u32 */ NDTPA_MCAST_PROBES, /* u32 */ + NDTPA_MCAST_REPROBES, /* u32 */ NDTPA_ANYCAST_DELAY, /* u64, msecs */ NDTPA_PROXY_DELAY, /* u64, msecs */ NDTPA_PROXY_QLEN, /* u32 */ diff --git a/include/net/neighbour.h b/include/net/neighbour.h index 34c996f..a2d9407 100644 --- a/include/net/neighbour.h +++ b/include/net/neighbour.h @@ -63,6 +63,7 @@ struct neigh_parms { int ucast_probes; int app_probes; int mcast_probes; + int mcast_reprobes; int anycast_delay; int proxy_delay; int proxy_qlen; diff --git a/net/core/neighbour.c b/net/core/neighbour.c index ebd4b21..eb573cf 100644 --- a/net/core/neighbour.c +++ b/net/core/neighbour.c @@ -843,9 +843,9 @@ next_elt: static __inline__ int neigh_max_probes(struct neighbour *n) { struct neigh_parms *p = n->parms; - return (n->nud_state & NUD_PROBE) ? - p->ucast_probes : - p->ucast_probes + p->app_probes + p->mcast_probes; + + return p->ucast_probes + p->app_probes + + (n->nud_state & NUD_PROBE) ? p->mcast_reprobes : p->mcast_probes; } static void neigh_invalidate(struct neighbour *neigh) @@ -982,6 +982,7 @@ int __neigh_event_send(struct neighbour *neigh, struct sk_buff *skb) goto out_unlock_bh; if (!(neigh->nud_state & (NUD_STALE | NUD_INCOMPLETE))) { + /* We are in (NUD_NONE | NUD_FAILED) */ if (neigh->parms->mcast_probes + neigh->parms->app_probes) { unsigned long next, now = jiffies; @@ -1783,6 +1784,7 @@ static int neightbl_fill_parms(struct sk_buff *skb, struct neigh_parms *parms) NLA_PUT_U32(skb, NDTPA_APP_PROBES, parms->app_probes); NLA_PUT_U32(skb, NDTPA_UCAST_PROBES, parms->ucast_probes); NLA_PUT_U32(skb, NDTPA_MCAST_PROBES, parms->mcast_probes); + NLA_PUT_U32(skb, NDTPA_MCAST_REPROBES, parms->mcast_reprobes); NLA_PUT_MSECS(skb, NDTPA_REACHABLE_TIME, parms->reachable_time); NLA_PUT_MSECS(skb, NDTPA_BASE_REACHABLE_TIME, parms->base_reachable_time); @@ -1932,6 +1934,7 @@ static const struct nla_policy nl_ntbl_parm_policy[NDTPA_MAX+1] = { [NDTPA_APP_PROBES] = { .type = NLA_U32 }, [NDTPA_UCAST_PROBES] = { .type = NLA_U32 }, [NDTPA_MCAST_PROBES] = { .type = NLA_U32 }, + [NDTPA_MCAST_REPROBES] = { .type = NLA_U32 }, [NDTPA_BASE_REACHABLE_TIME] = { .type = NLA_U64 }, [NDTPA_GC_STALETIME] = { .type = NLA_U64 }, [NDTPA_DELAY_PROBE_TIME] = { .type = NLA_U64 }, @@ -2023,6 +2026,9 @@ static int neightbl_set(struct sk_buff *skb, struct nlmsghdr *nlh, void *arg) case NDTPA_MCAST_PROBES: p->mcast_probes = nla_get_u32(tbp[i]); break; + case NDTPA_MCAST_REPROBES: + p->mcast_reprobes = nla_get_u32(tbp[i]); + break; case NDTPA_BASE_REACHABLE_TIME: p->base_reachable_time = nla_get_msecs(tbp[i]); break; @@ -2773,6 +2779,7 @@ enum { NEIGH_VAR_MCAST_PROBE, NEIGH_VAR_UCAST_PROBE, NEIGH_VAR_APP_PROBE, + NEIGH_VAR_MCAST_REPROBE, NEIGH_VAR_RETRANS_TIME, NEIGH_VAR_BASE_REACHABLE_TIME, NEIGH_VAR_DELAY_PROBE_TIME, @@ -2804,6 +2811,12 @@ static struct neigh_sysctl_table { .mode = 0644, .proc_handler = proc_dointvec, }, + [NEIGH_VAR_MCAST_REPROBE] = { + .procname = "mcast_resolicit", + .maxlen = sizeof(int), + .mode = 0644, + .proc_handler = proc_dointvec, + }, [NEIGH_VAR_UCAST_PROBE] = { .procname = "ucast_solicit", .maxlen = sizeof(int), @@ -2940,6 +2953,7 @@ int neigh_sysctl_register(struct net_device *dev, struct neigh_parms *p, goto err; t->neigh_vars[NEIGH_VAR_MCAST_PROBE].data = &p->mcast_probes; + t->neigh_vars[NEIGH_VAR_MCAST_REPROBE].data = &p->mcast_reprobes; t->neigh_vars[NEIGH_VAR_UCAST_PROBE].data = &p->ucast_probes; t->neigh_vars[NEIGH_VAR_APP_PROBE].data = &p->app_probes; t->neigh_vars[NEIGH_VAR_RETRANS_TIME].data = &p->retrans_time; -- 1.9.1