IP Multicast FIB (mfib)

 - IPv[46] mfib tables with support for (*,G/m), (*,G) and (S,G) exact and longest prefix match
 - Replication represented via a new replicate DPO.
 - RPF configuration and data-plane checking
 - data-plane signals sent to listening control planes.

The functions of multicast forwarding entries differ from their unicast conterparts, so we introduce a new mfib_table_t and mfib_entry_t objects. However, we re-use the fib_path_list to resolve and build the entry's output list. the fib_path_list provides the service to construct a replicate DPO for multicast.

'make tests' is added to with two new suites; TEST=mfib, this is invocation of the CLI command 'test mfib' which deals with many path add/remove, flag set/unset scenarios, TEST=ip-mcast, data-plane forwarding tests.

Updated applications to use the new MIFB functions;
  - IPv6 NS/RA.
  - DHCPv6
 unit tests for these are undated accordingly.

Change-Id: I49ec37b01f1b170335a5697541c8fd30e6d3a961
Signed-off-by: Neale Ranns <nranns@cisco.com>

1 files changed, 143 insertions, 0 deletions

diff --git a/src/vnet/dpo/replicate_dpo.h b/src/vnet/dpo/replicate_dpo.h
new file mode 100644
index 00000000000..a564739c9f2
--- /dev/null
+++ b/src/vnet/dpo/replicate_dpo.h
@@ -0,0 +1,143 @@
+/*
+ * Copyright (c) 2016 Cisco and/or its affiliates.
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at:
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+/**
+ * @brief
+ *
+ */
+
+#ifndef __REPLICATE_DPO_H__
+#define __REPLICATE_DPO_H__
+
+#include <vlib/vlib.h>
+#include <vnet/ip/lookup.h>
+#include <vnet/dpo/dpo.h>
+#include <vnet/dpo/load_balance.h>
+#include <vnet/fib/fib_types.h>
+
+/**
+ * replicate main
+ */
+typedef struct replicate_main_t_
+{
+    vlib_combined_counter_main_t repm_counters;
+} replicate_main_t;
+
+extern replicate_main_t replicate_main;
+
+/**
+ * The number of buckets that a load-balance object can have and still
+ * fit in one cache-line
+ */
+#define REP_NUM_INLINE_BUCKETS 4
+
+/**
+ * The FIB DPO provieds;
+ *  - load-balancing over the next DPOs in the chain/graph
+ *  - per-route counters
+ */
+typedef struct replicate_t_ {
+    /**
+     * number of buckets in the load-balance. always a power of 2.
+     */
+    u16 rep_n_buckets;
+
+   /**
+     * The protocol of packets that traverse this REP.
+     * need in combination with the flow hash config to determine how to hash.
+     * u8.
+     */
+    dpo_proto_t rep_proto;
+
+    /**
+     * The number of locks, which is approximately the number of users,
+     * of this load-balance.
+     * Load-balance objects of via-entries are heavily shared by recursives,
+     * so the lock count is a u32.
+     */
+    u32 rep_locks;
+
+    /**
+     * Vector of buckets containing the next DPOs, sized as repo_num
+     */
+    dpo_id_t *rep_buckets;
+
+    /**
+     * The rest of the cache line is used for buckets. In the common case
+     * where there there are less than 4 buckets, then the buckets are
+     * on the same cachlie and we save ourselves a pointer dereferance in 
+     * the data-path.
+     */
+    dpo_id_t rep_buckets_inline[REP_NUM_INLINE_BUCKETS];
+} replicate_t;
+
+STATIC_ASSERT(sizeof(replicate_t) <= CLIB_CACHE_LINE_BYTES,
+	      "A replicate object size exceeds one cachline");
+
+/**
+ * Flags controlling load-balance formatting/display
+ */
+typedef enum replicate_format_flags_t_ {
+    REPLICATE_FORMAT_NONE,
+    REPLICATE_FORMAT_DETAIL = (1 << 0),
+} replicate_format_flags_t;
+
+extern index_t replicate_create(u32 num_buckets,
+                                dpo_proto_t rep_proto);
+extern void replicate_multipath_update(
+    const dpo_id_t *dpo,
+    load_balance_path_t *next_hops);
+
+extern void replicate_set_bucket(index_t repi,
+				    u32 bucket,
+				    const dpo_id_t *next);
+
+extern u8* format_replicate(u8 * s, va_list * args);
+
+extern const dpo_id_t *replicate_get_bucket(index_t repi,
+					       u32 bucket);
+extern int replicate_is_drop(const dpo_id_t *dpo);
+
+/**
+ * The encapsulation breakages are for fast DP access
+ */
+extern replicate_t *replicate_pool;
+static inline replicate_t*
+replicate_get (index_t repi)
+{
+    return (pool_elt_at_index(replicate_pool, repi));
+}
+
+#define REP_HAS_INLINE_BUCKETS(_rep)		\
+    ((_rep)->rep_n_buckets <= REP_NUM_INLINE_BUCKETS)
+
+static inline const dpo_id_t *
+replicate_get_bucket_i (const replicate_t *rep,
+			   u32 bucket)
+{
+    ASSERT(bucket < rep->rep_n_buckets);
+
+    if (PREDICT_TRUE(REP_HAS_INLINE_BUCKETS(rep)))
+    {
+	return (&rep->rep_buckets_inline[bucket]);
+    }
+    else
+    {
+	return (&rep->rep_buckets[bucket]);
+    }
+}
+
+extern void replicate_module_init(void);
+
+#endif