1 files changed, 87 insertions, 19 deletions

diff --git a/src/vnet/ip/ip4_mtrie.h b/src/vnet/ip/ip4_mtrie.h
index 128195d3a52..be262c2c84d 100644
--- a/src/vnet/ip/ip4_mtrie.h
+++ b/src/vnet/ip/ip4_mtrie.h
@@ -47,16 +47,43 @@
 
 /* ip4 fib leafs: 4 ply 8-8-8-8 mtrie.
    1 + 2*adj_index for terminal leaves.
-   0 + 2*next_ply_index for non-terminals.
+   0 + 2*next_ply_index for non-terminals, i.e. PLYs
    1 => empty (adjacency index of zero is special miss adjacency). */
 typedef u32 ip4_fib_mtrie_leaf_t;
 
 #define IP4_FIB_MTRIE_LEAF_EMPTY (1 + 2*0)
 
 /**
+ * @brief the 16 way stride that is the top PLY of the mtrie
+ * We do not maintain the count of 'real' leaves in this PLY, since
+ * it is never removed. The FIB will destroy the mtrie and the ply once
+ * the FIB is destroyed.
+ */
+#define PLY_16_SIZE (1<<16)
+typedef struct ip4_fib_mtrie_16_ply_t_
+{
+  /**
+   * The leaves/slots/buckets to be filed with leafs
+   */
+  union
+  {
+    ip4_fib_mtrie_leaf_t leaves[PLY_16_SIZE];
+
+#ifdef CLIB_HAVE_VEC128
+    u32x4 leaves_as_u32x4[PLY_16_SIZE / 4];
+#endif
+  };
+
+  /**
+   * Prefix length for terminal leaves.
+   */
+  u8 dst_address_bits_of_leaves[PLY_16_SIZE];
+} ip4_fib_mtrie_16_ply_t;
+
+/**
  * @brief One ply of the 4 ply mtrie fib.
  */
-typedef struct
+typedef struct ip4_fib_mtrie_8_ply_t_
 {
   /**
    * The leaves/slots/buckets to be filed with leafs
@@ -90,34 +117,72 @@ typedef struct
   /* Pad to cache line boundary. */
   u8 pad[CLIB_CACHE_LINE_BYTES - 2 * sizeof (i32)];
 }
-ip4_fib_mtrie_ply_t;
+ip4_fib_mtrie_8_ply_t;
 
-STATIC_ASSERT (0 == sizeof (ip4_fib_mtrie_ply_t) % CLIB_CACHE_LINE_BYTES,
+STATIC_ASSERT (0 == sizeof (ip4_fib_mtrie_8_ply_t) % CLIB_CACHE_LINE_BYTES,
 	       "IP4 Mtrie ply cache line");
 
+/**
+ * @brief The mutiway-TRIE.
+ * There is no data associated with the mtrie apart from the top PLY
+ */
 typedef struct
 {
-  /* Pool of plies.  Index zero is root ply. */
-  ip4_fib_mtrie_ply_t *ply_pool;
+  /**
+   * Embed the PLY with the mtrie struct. This means that the Data-plane
+   * 'get me the mtrie' returns the first ply, and not an indirect 'pointer'
+   * to it. therefore no cachline misses in the data-path.
+   */
+  ip4_fib_mtrie_16_ply_t root_ply;
 } ip4_fib_mtrie_t;
 
-void ip4_fib_mtrie_init (ip4_fib_mtrie_t * m);
+/**
+ * @brief Initialise an mtrie
+ */
+void ip4_mtrie_init (ip4_fib_mtrie_t * m);
 
-struct ip4_fib_t;
+/**
+ * @brief Free an mtrie, It must be emty when free'd
+ */
+void ip4_mtrie_free (ip4_fib_mtrie_t * m);
 
-void ip4_fib_mtrie_add_del_route (struct ip4_fib_t *f,
-				  ip4_address_t dst_address,
-				  u32 dst_address_length,
-				  u32 adj_index, u32 is_del);
+/**
+ * @brief Add a route/rntry to the mtrie
+ */
+void ip4_fib_mtrie_route_add (ip4_fib_mtrie_t * m,
+			      const ip4_address_t * dst_address,
+			      u32 dst_address_length, u32 adj_index);
+/**
+ * @brief remove a route/rntry to the mtrie
+ */
+void ip4_fib_mtrie_route_del (ip4_fib_mtrie_t * m,
+			      const ip4_address_t * dst_address,
+			      u32 dst_address_length,
+			      u32 adj_index,
+			      u32 cover_address_length, u32 cover_adj_index);
 
+/**
+ * @brief Format/display the contents of the mtrie
+ */
 format_function_t format_ip4_fib_mtrie;
 
+/**
+ * @brief A global pool of 8bit stride plys
+ */
+extern ip4_fib_mtrie_8_ply_t *ip4_ply_pool;
+
+/**
+ * Is the leaf terminal (i.e. an LB index) or non-terminak (i.e. a PLY index)
+ */
 always_inline u32
 ip4_fib_mtrie_leaf_is_terminal (ip4_fib_mtrie_leaf_t n)
 {
   return n & 1;
 }
 
+/**
+ * From the stored slot value extract the LB index value
+ */
 always_inline u32
 ip4_fib_mtrie_leaf_get_adj_index (ip4_fib_mtrie_leaf_t n)
 {
@@ -125,35 +190,38 @@ ip4_fib_mtrie_leaf_get_adj_index (ip4_fib_mtrie_leaf_t n)
   return n >> 1;
 }
 
-/* Lookup step.  Processes 1 byte of 4 byte ip4 address. */
+/**
+ * @brief Lookup step.  Processes 1 byte of 4 byte ip4 address.
+ */
 always_inline ip4_fib_mtrie_leaf_t
 ip4_fib_mtrie_lookup_step (const ip4_fib_mtrie_t * m,
 			   ip4_fib_mtrie_leaf_t current_leaf,
 			   const ip4_address_t * dst_address,
 			   u32 dst_address_byte_index)
 {
-  ip4_fib_mtrie_ply_t *ply;
+  ip4_fib_mtrie_8_ply_t *ply;
+
   uword current_is_terminal = ip4_fib_mtrie_leaf_is_terminal (current_leaf);
 
   if (!current_is_terminal)
     {
-      ply = m->ply_pool + (current_leaf >> 1);
+      ply = ip4_ply_pool + (current_leaf >> 1);
       return (ply->leaves[dst_address->as_u8[dst_address_byte_index]]);
     }
 
   return current_leaf;
 }
 
-/* Lookup step.  Processes 1 byte of 4 byte ip4 address. */
+/**
+ * @brief Lookup step number 1.  Processes 2 bytes of 4 byte ip4 address.
+ */
 always_inline ip4_fib_mtrie_leaf_t
 ip4_fib_mtrie_lookup_step_one (const ip4_fib_mtrie_t * m,
 			       const ip4_address_t * dst_address)
 {
   ip4_fib_mtrie_leaf_t next_leaf;
-  ip4_fib_mtrie_ply_t *ply;
 
-  ply = m->ply_pool;
-  next_leaf = ply->leaves[dst_address->as_u8[0]];
+  next_leaf = m->root_ply.leaves[dst_address->as_u16[0]];
 
   return next_leaf;
 }