VPP-1024: rewrite buffer trajectory tracer

Use a proper u16 * vector to capture node indices, since vpp w/
plugins now exceeds 255 graph nodes

Change-Id: Ic48cad676fa3a6116413ddf08c083dd9660783f1
Signed-off-by: Dave Barach <dave@barachs.net>

1 files changed, 95 insertions, 0 deletions

diff --git a/src/vnet/util/trajectory.c b/src/vnet/util/trajectory.c
new file mode 100644
index 00000000000..24b51254ecd
--- /dev/null
+++ b/src/vnet/util/trajectory.c
@@ -0,0 +1,95 @@
+/*
+ * Copyright (c) 2017 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.
+ */
+
+/** \file
+ * Buffer trace trajectory utilities
+ */
+
+#include <vnet/vnet.h>
+
+/**
+ * Dump a trajectory trace, reasonably easy to call from gdb
+ */
+void
+vnet_dump_trajectory_trace (vlib_main_t * vm, u32 bi)
+{
+#if VLIB_BUFFER_TRACE_TRAJECTORY > 0
+  vlib_node_main_t *vnm = &vm->node_main;
+  vlib_buffer_t *b;
+  u16 *trace;
+  u8 i;
+
+  b = vlib_get_buffer (vm, bi);
+
+  trace = vnet_buffer2 (b)->trajectory_trace;
+
+  fformat (stderr, "Context trace for bi %d b 0x%llx, visited %d\n",
+	   bi, b, vec_len (trace));
+
+  for (i = 0; i < vec_len (trace); i++)
+    {
+      u32 node_index;
+
+      node_index = trace[i];
+
+      if (node_index > vec_len (vnm->nodes))
+	{
+	  fformat (stderr, "Skip bogus node index %d\n", node_index);
+	  continue;
+	}
+
+      fformat (stderr, "%v (%d)\n", vnm->nodes[node_index]->name, node_index);
+    }
+#else
+  fformat (stderr, "in vlib/buffers.h, "
+	   "#define VLIB_BUFFER_TRACE_TRAJECTORY 1\n");
+
+#endif
+}
+
+#if VLIB_BUFFER_TRACE_TRAJECTORY > 0
+
+void
+init_trajectory_trace (vlib_buffer_t * b)
+{
+  vec_validate (vnet_buffer2 (b)->trajectory_trace, 7);
+  _vec_len (vnet_buffer2 (b)->trajectory_trace) = 0;
+}
+
+void
+add_trajectory_trace (vlib_buffer_t * b, u32 node_index)
+{
+  vec_add1 (vnet_buffer2 (b)->trajectory_trace, (u16) node_index);
+}
+
+static clib_error_t *
+trajectory_trace_init (vlib_main_t * vm)
+{
+  vlib_buffer_trace_trajectory_cb = add_trajectory_trace;
+  vlib_buffer_trace_trajectory_init_cb = init_trajectory_trace;
+  return 0;
+}
+
+VLIB_INIT_FUNCTION (trajectory_trace_init);
+
+#endif
+
+/*
+ * fd.io coding-style-patch-verification: ON
+ *
+ * Local Variables:
+ * eval: (c-set-style "gnu")
+ * End:
+ */