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diff --git a/src/vnet/l2/feat_bitmap.h b/src/vnet/l2/feat_bitmap.h
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+++ b/src/vnet/l2/feat_bitmap.h
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+/*
+ * feat_bitmap.h: bitmap for managing feature invocation
+ *
+ * Copyright (c) 2013 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.
+ */
+
+#ifndef included_vnet_l2_feat_bitmap_h
+#define included_vnet_l2_feat_bitmap_h
+
+#include <vlib/vlib.h>
+#include <vnet/vnet.h>
+
+/*
+ * The feature bitmap is a way of organizing input and output feature graph nodes.
+ * The set of features to be executed are arranged in a bitmap with one bit per
+ * feature and each bit positioned in the same order that the features should be
+ * executed. Features can be dynamically removed from the set by masking off their
+ * corresponding bits. The bitmap is stored in packet context. Each feature clears
+ * its bit and then calls feat_bitmap_get_next_node_index() to go to the next
+ * graph node.
+ */
+
+
+/* 32 features in a u32 bitmap */
+#define FEAT_MAX 32
+
+/**
+ Initialize the feature next-node indexes of a graph node.
+ Should be called by the init function of each feature graph node.
+*/
+always_inline void
+feat_bitmap_init_next_nodes (vlib_main_t * vm, u32 node_index,	/* the current graph node index  */
+			     u32 num_features,	/* number of entries in feat_names */
+			     char **feat_names,	/* array of feature graph node names */
+			     u32 * next_nodes)	/* array of 32 next indexes to init */
+{
+  u32 idx;
+
+  ASSERT (num_features <= FEAT_MAX);
+
+  for (idx = 0; idx < num_features; idx++)
+    {
+      if (vlib_get_node_by_name (vm, (u8 *) feat_names[idx]))
+	{
+	  next_nodes[idx] =
+	    vlib_node_add_named_next (vm, node_index, feat_names[idx]);
+	}
+      else
+	{			// Node may be in plugin which is not installed, use drop node
+	  next_nodes[idx] =
+	    vlib_node_add_named_next (vm, node_index, "feature-bitmap-drop");
+	}
+    }
+
+  /* All unassigned bits go to the drop node */
+  for (; idx < FEAT_MAX; idx++)
+    {
+      next_nodes[idx] = vlib_node_add_named_next (vm, node_index,
+						  "feature-bitmap-drop");
+    }
+}
+
+/**
+ Return the graph node index for the feature corresponding to the
+ first set bit in the bitmap.
+*/
+always_inline
+  u32 feat_bitmap_get_next_node_index (u32 * next_nodes, u32 bitmap)
+{
+  u32 first_bit;
+
+  count_leading_zeros (first_bit, bitmap);
+  first_bit = uword_bits - 1 - first_bit;
+  return next_nodes[first_bit];
+}
+
+#endif /* included_vnet_l2_feat_bitmap_h */
+
+/*
+ * fd.io coding-style-patch-verification: ON
+ *
+ * Local Variables:
+ * eval: (c-set-style "gnu")
+ * End:
+ */