Petr Machata
2023-Jan-26 17:01 UTC
[Bridge] [PATCH net-next 06/16] net: bridge: Add a tracepoint for MDB overflows
The following patch will add two more maximum MDB allowances to the global
one, mcast_hash_max, that exists today. In all these cases, attempts to add
MDB entries above the configured maximums through netlink, fail noisily and
obviously. Such visibility is missing when adding entries through the
control plane traffic, by IGMP or MLD packets.
To improve visibility in those cases, add a trace point that reports the
violation, including the relevant netdevice (be it a slave or the bridge
itself), and the MDB entry parameters:
# perf record -e bridge:br_mdb_full &
# [...]
# perf script | cut -d: -f4-
dev v2 af 2 src 192.0.2.1/:: grp 239.1.1.1/::/00:00:00:00:00:00 vid 0
dev v2 af 10 src 0.0.0.0/2001:db8:1::1 grp 0.0.0.0/ff0e::1/00:00:00:00:00:00
vid 0
dev v2 af 2 src 192.0.2.1/:: grp 239.1.1.1/::/00:00:00:00:00:00 vid 10
dev v2 af 10 src 0.0.0.0/2001:db8:1::1 grp 0.0.0.0/ff0e::1/00:00:00:00:00:00
vid 10
CC: Steven Rostedt <rostedt at goodmis.org>
CC: linux-trace-kernel at vger.kernel.org
Signed-off-by: Petr Machata <petrm at nvidia.com>
Reviewed-by: Ido Schimmel <idosch at nvidia.com>
---
include/trace/events/bridge.h | 67 +++++++++++++++++++++++++++++++++++
net/core/net-traces.c | 1 +
2 files changed, 68 insertions(+)
diff --git a/include/trace/events/bridge.h b/include/trace/events/bridge.h
index 6b200059c2c5..00d5e2dcb3ad 100644
--- a/include/trace/events/bridge.h
+++ b/include/trace/events/bridge.h
@@ -122,6 +122,73 @@ TRACE_EVENT(br_fdb_update,
__entry->flags)
);
+TRACE_EVENT(br_mdb_full,
+
+ TP_PROTO(const struct net_device *dev,
+ const struct br_ip *group),
+
+ TP_ARGS(dev, group),
+
+ TP_STRUCT__entry(
+ __string(dev, dev->name)
+ __field(int, af)
+ __field(u16, vid)
+ __array(__u8, src4, 4)
+ __array(__u8, src6, 16)
+ __array(__u8, grp4, 4)
+ __array(__u8, grp6, 16)
+ __array(__u8, grpmac, ETH_ALEN) /* For af == 0. */
+ ),
+
+ TP_fast_assign(
+ __assign_str(dev, dev->name);
+ __entry->vid = group->vid;
+
+ if (!group->proto) {
+ __entry->af = 0;
+
+ memset(__entry->src4, 0, sizeof(__entry->src4));
+ memset(__entry->src6, 0, sizeof(__entry->src6));
+ memset(__entry->grp4, 0, sizeof(__entry->grp4));
+ memset(__entry->grp6, 0, sizeof(__entry->grp6));
+ memcpy(__entry->grpmac, group->dst.mac_addr, ETH_ALEN);
+ } else if (group->proto == htons(ETH_P_IP)) {
+ __be32 *p32;
+
+ __entry->af = AF_INET;
+
+ p32 = (__be32 *) __entry->src4;
+ *p32 = group->src.ip4;
+
+ p32 = (__be32 *) __entry->grp4;
+ *p32 = group->dst.ip4;
+
+ memset(__entry->src6, 0, sizeof(__entry->src6));
+ memset(__entry->grp6, 0, sizeof(__entry->grp6));
+ memset(__entry->grpmac, 0, ETH_ALEN);
+#if IS_ENABLED(CONFIG_IPV6)
+ } else {
+ struct in6_addr *in6;
+
+ __entry->af = AF_INET6;
+
+ in6 = (struct in6_addr *)__entry->src6;
+ *in6 = group->src.ip6;
+
+ in6 = (struct in6_addr *)__entry->grp6;
+ *in6 = group->dst.ip6;
+
+ memset(__entry->src4, 0, sizeof(__entry->src4));
+ memset(__entry->grp4, 0, sizeof(__entry->grp4));
+ memset(__entry->grpmac, 0, ETH_ALEN);
+#endif
+ }
+ ),
+
+ TP_printk("dev %s af %u src %pI4/%pI6c grp %pI4/%pI6c/%pM vid %u",
+ __get_str(dev), __entry->af, __entry->src4, __entry->src6,
+ __entry->grp4, __entry->grp6, __entry->grpmac, __entry->vid)
+);
#endif /* _TRACE_BRIDGE_H */
diff --git a/net/core/net-traces.c b/net/core/net-traces.c
index ee7006bbe49b..805b7385dd8d 100644
--- a/net/core/net-traces.c
+++ b/net/core/net-traces.c
@@ -41,6 +41,7 @@ EXPORT_TRACEPOINT_SYMBOL_GPL(br_fdb_add);
EXPORT_TRACEPOINT_SYMBOL_GPL(br_fdb_external_learn_add);
EXPORT_TRACEPOINT_SYMBOL_GPL(fdb_delete);
EXPORT_TRACEPOINT_SYMBOL_GPL(br_fdb_update);
+EXPORT_TRACEPOINT_SYMBOL_GPL(br_mdb_full);
#endif
#if IS_ENABLED(CONFIG_PAGE_POOL)
--
2.39.0
Steven Rostedt
2023-Jan-26 17:53 UTC
[Bridge] [PATCH net-next 06/16] net: bridge: Add a tracepoint for MDB overflows
On Thu, 26 Jan 2023 18:01:14 +0100 Petr Machata <petrm at nvidia.com> wrote:> The following patch will add two more maximum MDB allowances to the global > one, mcast_hash_max, that exists today. In all these cases, attempts to add > MDB entries above the configured maximums through netlink, fail noisily and > obviously. Such visibility is missing when adding entries through the > control plane traffic, by IGMP or MLD packets. > > To improve visibility in those cases, add a trace point that reports the > violation, including the relevant netdevice (be it a slave or the bridge > itself), and the MDB entry parameters: > > # perf record -e bridge:br_mdb_full & > # [...] > # perf script | cut -d: -f4- > dev v2 af 2 src 192.0.2.1/:: grp 239.1.1.1/::/00:00:00:00:00:00 vid 0 > dev v2 af 10 src 0.0.0.0/2001:db8:1::1 grp 0.0.0.0/ff0e::1/00:00:00:00:00:00 vid 0 > dev v2 af 2 src 192.0.2.1/:: grp 239.1.1.1/::/00:00:00:00:00:00 vid 10 > dev v2 af 10 src 0.0.0.0/2001:db8:1::1 grp 0.0.0.0/ff0e::1/00:00:00:00:00:00 vid 10 > > CC: Steven Rostedt <rostedt at goodmis.org> > CC: linux-trace-kernel at vger.kernel.org > Signed-off-by: Petr Machata <petrm at nvidia.com> > Reviewed-by: Ido Schimmel <idosch at nvidia.com> > --- > include/trace/events/bridge.h | 67 +++++++++++++++++++++++++++++++++++ > net/core/net-traces.c | 1 + > 2 files changed, 68 insertions(+) > > diff --git a/include/trace/events/bridge.h b/include/trace/events/bridge.h > index 6b200059c2c5..00d5e2dcb3ad 100644 > --- a/include/trace/events/bridge.h > +++ b/include/trace/events/bridge.h > @@ -122,6 +122,73 @@ TRACE_EVENT(br_fdb_update, > __entry->flags) > ); > > +TRACE_EVENT(br_mdb_full, > + > + TP_PROTO(const struct net_device *dev, > + const struct br_ip *group), > + > + TP_ARGS(dev, group), > + > + TP_STRUCT__entry( > + __string(dev, dev->name) > + __field(int, af) > + __field(u16, vid) > + __array(__u8, src4, 4) > + __array(__u8, src6, 16) > + __array(__u8, grp4, 4) > + __array(__u8, grp6, 16) > + __array(__u8, grpmac, ETH_ALEN) /* For af == 0. */Instead of wasting ring buffer space, why not just have: __array(__u8, src, 16) __array(__u8, grp, 16)> + ), > + > + TP_fast_assign( > + __assign_str(dev, dev->name); > + __entry->vid = group->vid; > + > + if (!group->proto) { > + __entry->af = 0; > + > + memset(__entry->src4, 0, sizeof(__entry->src4)); > + memset(__entry->src6, 0, sizeof(__entry->src6)); > + memset(__entry->grp4, 0, sizeof(__entry->grp4)); > + memset(__entry->grp6, 0, sizeof(__entry->grp6)); > + memcpy(__entry->grpmac, group->dst.mac_addr, ETH_ALEN); > + } else if (group->proto == htons(ETH_P_IP)) { > + __be32 *p32; > + > + __entry->af = AF_INET; > + > + p32 = (__be32 *) __entry->src4; > + *p32 = group->src.ip4; > + > + p32 = (__be32 *) __entry->grp4; > + *p32 = group->dst.ip4;struct in6_addr *in6; in6 = (struct in6_addr *)__entry->src; ipv6_addr_set_v4mapped(group->src.ip4, in6); in6 = (struct in6_addr *)__entry->grp; ipv6_addr_set_v4mapped(group->grp.ip4, in6);> + > + memset(__entry->src6, 0, sizeof(__entry->src6)); > + memset(__entry->grp6, 0, sizeof(__entry->grp6)); > + memset(__entry->grpmac, 0, ETH_ALEN); > +#if IS_ENABLED(CONFIG_IPV6) > + } else { > + struct in6_addr *in6; > + > + __entry->af = AF_INET6; > + > + in6 = (struct in6_addr *)__entry->src6; > + *in6 = group->src.ip6; > + > + in6 = (struct in6_addr *)__entry->grp6; > + *in6 = group->dst.ip6; > + > + memset(__entry->src4, 0, sizeof(__entry->src4)); > + memset(__entry->grp4, 0, sizeof(__entry->grp4)); > + memset(__entry->grpmac, 0, ETH_ALEN); > +#endif > + } > + ), > + > + TP_printk("dev %s af %u src %pI4/%pI6c grp %pI4/%pI6c/%pM vid %u", > + __get_str(dev), __entry->af, __entry->src4, __entry->src6, > + __entry->grp4, __entry->grp6, __entry->grpmac, __entry->vid)And just have: TP_printk("dev %s af %u src %pI6c grp %pI6c/%pM vid %u", __get_str(dev), __entry->af, __entry->src, __entry->grp, __entry->grpmac, __entry->vid) As the %pI6c should detect that it's a ipv4 address and show that. -- Steve> +); > > #endif /* _TRACE_BRIDGE_H */ > > diff --git a/net/core/net-traces.c b/net/core/net-traces.c > index ee7006bbe49b..805b7385dd8d 100644 > --- a/net/core/net-traces.c > +++ b/net/core/net-traces.c > @@ -41,6 +41,7 @@ EXPORT_TRACEPOINT_SYMBOL_GPL(br_fdb_add); > EXPORT_TRACEPOINT_SYMBOL_GPL(br_fdb_external_learn_add); > EXPORT_TRACEPOINT_SYMBOL_GPL(fdb_delete); > EXPORT_TRACEPOINT_SYMBOL_GPL(br_fdb_update); > +EXPORT_TRACEPOINT_SYMBOL_GPL(br_mdb_full); > #endif > > #if IS_ENABLED(CONFIG_PAGE_POOL)