We want to be able to keep more spaces available in our queue for
processing incoming IPv6 multicast traffic (adding (S,G) entries) - this
lets us learn more groups faster, rather than dropping them at this stage.
Signed-off-by: Brodie Greenfield <brodie.greenfi...@alliedtelesis.co.nz>
---
Documentation/networking/ip-sysctl.txt | 8 ++++++++
include/net/netns/ipv6.h | 1 +
net/ipv6/af_inet6.c | 1 +
net/ipv6/ip6mr.c | 4 +++-
net/ipv6/sysctl_net_ipv6.c | 7 +++++++
5 files changed, 20 insertions(+), 1 deletion(-)
diff --git a/Documentation/networking/ip-sysctl.txt
b/Documentation/networking/ip-sysctl.txt
index 02f77e932adf..68eada3ca915 100644
--- a/Documentation/networking/ip-sysctl.txt
+++ b/Documentation/networking/ip-sysctl.txt
@@ -1481,6 +1481,14 @@ skip_notify_on_dev_down - BOOLEAN
on userspace caches to track link events and evict routes.
Default: false (generate message)
+ip6_mr_cache_queue_length - INTEGER
+ Limit the number of multicast packets we can have in the queue to be
+ resolved.
+ Bear in mind that when an unresolved multicast packet is received,
+ there is an O(n) traversal of the queue. This should be considered
+ if increasing.
+ Default: 10
+
IPv6 Fragmentation:
ip6frag_high_thresh - INTEGER
diff --git a/include/net/netns/ipv6.h b/include/net/netns/ipv6.h
index ef1ed529f33c..84b58424c799 100644
--- a/include/net/netns/ipv6.h
+++ b/include/net/netns/ipv6.h
@@ -46,6 +46,7 @@ struct netns_sysctl_ipv6 {
int max_hbh_opts_len;
int seg6_flowlabel;
bool skip_notify_on_dev_down;
+ unsigned int ip6_mr_cache_queue_length;
};
struct netns_ipv6 {
diff --git a/net/ipv6/af_inet6.c b/net/ipv6/af_inet6.c
index d99753b5e39b..6551bb63e5a2 100644
--- a/net/ipv6/af_inet6.c
+++ b/net/ipv6/af_inet6.c
@@ -856,6 +856,7 @@ static int __net_init inet6_net_init(struct net *net)
net->ipv6.sysctl.max_hbh_opts_cnt = IP6_DEFAULT_MAX_HBH_OPTS_CNT;
net->ipv6.sysctl.max_dst_opts_len = IP6_DEFAULT_MAX_DST_OPTS_LEN;
net->ipv6.sysctl.max_hbh_opts_len = IP6_DEFAULT_MAX_HBH_OPTS_LEN;
+ net->ipv6.sysctl.ip6_mr_cache_queue_length = 10;
atomic_set(&net->ipv6.fib6_sernum, 1);
err = ipv6_init_mibs(net);
diff --git a/net/ipv6/ip6mr.c b/net/ipv6/ip6mr.c
index cc01aa3f2b5e..bb445871437e 100644
--- a/net/ipv6/ip6mr.c
+++ b/net/ipv6/ip6mr.c
@@ -1135,6 +1135,7 @@ static int ip6mr_cache_report(struct mr_table *mrt,
struct sk_buff *pkt,
static int ip6mr_cache_unresolved(struct mr_table *mrt, mifi_t mifi,
struct sk_buff *skb, struct net_device *dev)
{
+ struct net *net = dev_net(dev);
struct mfc6_cache *c;
bool found = false;
int err;
@@ -1153,7 +1154,8 @@ static int ip6mr_cache_unresolved(struct mr_table *mrt,
mifi_t mifi,
* Create a new entry if allowable
*/
- if (atomic_read(&mrt->cache_resolve_queue_len) >= 10 ||
+ if (atomic_read(&mrt->cache_resolve_queue_len) >=
+ net->ipv6.sysctl.ip6_mr_cache_queue_length ||
(c = ip6mr_cache_alloc_unres()) == NULL) {
spin_unlock_bh(&mfc_unres_lock);
diff --git a/net/ipv6/sysctl_net_ipv6.c b/net/ipv6/sysctl_net_ipv6.c
index e15cd37024fd..a27299d4cc34 100644
--- a/net/ipv6/sysctl_net_ipv6.c
+++ b/net/ipv6/sysctl_net_ipv6.c
@@ -159,6 +159,13 @@ static struct ctl_table ipv6_table_template[] = {
.mode = 0644,
.proc_handler = proc_dointvec
},
+ {
+ .procname = "ip6_mr_cache_queue_length",
+ .data =
&init_net.ipv6.sysctl.ip6_mr_cache_queue_length,
+ .maxlen = sizeof(int),
+ .mode = 0644,
+ .proc_handler = proc_dointvec
+ },
{ }
};
--
2.21.0
