vlib: packet tracer support for pkt thread handoffs

Type: feature

Change-Id: Ia3d9a47679202c2a47cd3746b50e86c6b8627ef6
Signed-off-by: Dave Barach <dave@barachs.net>

5 files changed, 536 insertions, 0 deletions

diff --git a/src/examples/handoffdemo/CMakeLists.txt b/src/examples/handoffdemo/CMakeLists.txt
new file mode 100644
index 00000000000..12bda6cffff
--- /dev/null
+++ b/src/examples/handoffdemo/CMakeLists.txt
@@ -0,0 +1,20 @@
+
+# Copyright (c) <current-year> <your-organization>
+# 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.
+
+add_vpp_plugin(handoffdemo
+  SOURCES
+  handoffdemo.c
+  node.c
+  handoffdemo.h
+)
diff --git a/src/examples/handoffdemo/README.md b/src/examples/handoffdemo/README.md
new file mode 100644
index 00000000000..3787731c73f
--- /dev/null
+++ b/src/examples/handoffdemo/README.md
@@ -0,0 +1,186 @@
+# Handoff queue demo plugin
+
+This plugin provides a simplified example of how to hand off
+packets between threads. I used it to debug packet-tracer handoff
+tracing support.
+
+# Packet generator input script
+
+```
+ packet-generator new {
+    name x
+    limit 5
+    size 128-128
+    interface local0
+    node handoffdemo-1
+    data {
+        incrementing 30
+    }
+ }
+```
+# Start vpp with 2 worker threads
+
+The demo plugin hands packets from worker 1 to worker 2.
+
+# Enable tracing, and start the packet generator
+
+```
+  trace add pg-input 100
+  packet-generator enable
+```
+
+# Sample Run
+
+```
+  DBGvpp# ex /tmp/pg_input_script
+  DBGvpp# pa en
+  DBGvpp# sh err
+   Count                    Node                  Reason
+         5              handoffdemo-1             packets handed off processed
+         5              handoffdemo-2             completed packets
+  DBGvpp# show run
+  Thread 1 vpp_wk_0 (lcore 0)
+  Time 133.9, average vectors/node 5.00, last 128 main loops 0.00 per node 0.00
+    vector rates in 3.7331e-2, out 0.0000e0, drop 0.0000e0, punt 0.0000e0
+               Name                 State         Calls          Vectors        Suspends         Clocks       Vectors/Call
+  handoffdemo-1                    active                  1               5               0          4.76e3            5.00
+  pg-input                        disabled                 2               5               0          5.58e4            2.50
+  unix-epoll-input                 polling             22760               0               0          2.14e7            0.00
+  ---------------
+  Thread 2 vpp_wk_1 (lcore 2)
+  Time 133.9, average vectors/node 5.00, last 128 main loops 0.00 per node 0.00
+    vector rates in 0.0000e0, out 0.0000e0, drop 3.7331e-2, punt 0.0000e0
+               Name                 State         Calls          Vectors        Suspends         Clocks       Vectors/Call
+  drop                             active                  1               5               0          1.35e4            5.00
+  error-drop                       active                  1               5               0          2.52e4            5.00
+  handoffdemo-2                    active                  1               5               0          2.56e4            5.00
+  unix-epoll-input                 polling             22406               0               0          2.18e7            0.00
+```
+
+Enable the packet tracer and run it again...
+
+```
+  DBGvpp# trace add pg-input 100
+  DBGvpp# pa en
+  DBGvpp# sh trace
+  sh trace
+  ------------------- Start of thread 0 vpp_main -------------------
+  No packets in trace buffer
+  ------------------- Start of thread 1 vpp_wk_0 -------------------
+  Packet 1
+
+  00:06:50:520688: pg-input
+    stream x, 128 bytes, 0 sw_if_index
+    current data 0, length 128, buffer-pool 0, ref-count 1, trace handle 0x1000000
+    00000000: 000102030405060708090a0b0c0d0e0f101112131415161718191a1b1c1d0000
+    00000020: 0000000000000000000000000000000000000000000000000000000000000000
+    00000040: 0000000000000000000000000000000000000000000000000000000000000000
+    00000060: 0000000000000000000000000000000000000000000000000000000000000000
+  00:06:50:520762: handoffdemo-1
+    HANDOFFDEMO: current thread 1
+
+  Packet 2
+
+  00:06:50:520688: pg-input
+    stream x, 128 bytes, 0 sw_if_index
+    current data 0, length 128, buffer-pool 0, ref-count 1, trace handle 0x1000001
+    00000000: 000102030405060708090a0b0c0d0e0f101112131415161718191a1b1c1d0000
+    00000020: 0000000000000000000000000000000000000000000000000000000000000000
+    00000040: 0000000000000000000000000000000000000000000000000000000000000000
+    00000060: 0000000000000000000000000000000000000000000000000000000000000000
+  00:06:50:520762: handoffdemo-1
+    HANDOFFDEMO: current thread 1
+
+  Packet 3
+
+  00:06:50:520688: pg-input
+    stream x, 128 bytes, 0 sw_if_index
+    current data 0, length 128, buffer-pool 0, ref-count 1, trace handle 0x1000002
+    00000000: 000102030405060708090a0b0c0d0e0f101112131415161718191a1b1c1d0000
+    00000020: 0000000000000000000000000000000000000000000000000000000000000000
+    00000040: 0000000000000000000000000000000000000000000000000000000000000000
+    00000060: 0000000000000000000000000000000000000000000000000000000000000000
+  00:06:50:520762: handoffdemo-1
+    HANDOFFDEMO: current thread 1
+
+  Packet 4
+
+  00:06:50:520688: pg-input
+    stream x, 128 bytes, 0 sw_if_index
+    current data 0, length 128, buffer-pool 0, ref-count 1, trace handle 0x1000003
+    00000000: 000102030405060708090a0b0c0d0e0f101112131415161718191a1b1c1d0000
+    00000020: 0000000000000000000000000000000000000000000000000000000000000000
+    00000040: 0000000000000000000000000000000000000000000000000000000000000000
+    00000060: 0000000000000000000000000000000000000000000000000000000000000000
+  00:06:50:520762: handoffdemo-1
+    HANDOFFDEMO: current thread 1
+
+  Packet 5
+
+  00:06:50:520688: pg-input
+    stream x, 128 bytes, 0 sw_if_index
+    current data 0, length 128, buffer-pool 0, ref-count 1, trace handle 0x1000004
+    00000000: 000102030405060708090a0b0c0d0e0f101112131415161718191a1b1c1d0000
+    00000020: 0000000000000000000000000000000000000000000000000000000000000000
+    00000040: 0000000000000000000000000000000000000000000000000000000000000000
+    00000060: 0000000000000000000000000000000000000000000000000000000000000000
+  00:06:50:520762: handoffdemo-1
+    HANDOFFDEMO: current thread 1
+
+  ------------------- Start of thread 2 vpp_wk_1 -------------------
+  Packet 1
+
+  00:06:50:520796: handoff_trace
+    HANDED-OFF: from thread 1 trace index 0
+  00:06:50:520796: handoffdemo-2
+    HANDOFFDEMO: current thread 2
+  00:06:50:520867: error-drop
+    rx:local0
+  00:06:50:520914: drop
+    handoffdemo-2: completed packets
+
+  Packet 2
+
+  00:06:50:520796: handoff_trace
+    HANDED-OFF: from thread 1 trace index 1
+  00:06:50:520796: handoffdemo-2
+    HANDOFFDEMO: current thread 2
+  00:06:50:520867: error-drop
+    rx:local0
+  00:06:50:520914: drop
+    handoffdemo-2: completed packets
+
+  Packet 3
+
+  00:06:50:520796: handoff_trace
+    HANDED-OFF: from thread 1 trace index 2
+  00:06:50:520796: handoffdemo-2
+    HANDOFFDEMO: current thread 2
+  00:06:50:520867: error-drop
+    rx:local0
+  00:06:50:520914: drop
+    handoffdemo-2: completed packets
+
+  Packet 4
+
+  00:06:50:520796: handoff_trace
+    HANDED-OFF: from thread 1 trace index 3
+  00:06:50:520796: handoffdemo-2
+    HANDOFFDEMO: current thread 2
+  00:06:50:520867: error-drop
+    rx:local0
+  00:06:50:520914: drop
+    handoffdemo-2: completed packets
+
+  Packet 5
+
+  00:06:50:520796: handoff_trace
+    HANDED-OFF: from thread 1 trace index 4
+  00:06:50:520796: handoffdemo-2
+    HANDOFFDEMO: current thread 2
+  00:06:50:520867: error-drop
+    rx:local0
+  00:06:50:520914: drop
+    handoffdemo-2: completed packets
+ DBGvpp#
+```
diff --git a/src/examples/handoffdemo/handoffdemo.c b/src/examples/handoffdemo/handoffdemo.c
new file mode 100644
index 00000000000..a1dad44d28d
--- /dev/null
+++ b/src/examples/handoffdemo/handoffdemo.c
@@ -0,0 +1,39 @@
+/*
+ * handoffdemo.c - skeleton vpp engine plug-in
+ *
+ * Copyright (c) <current-year> <your-organization>
+ * 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.
+ */
+
+#include <vnet/vnet.h>
+#include <vnet/plugin/plugin.h>
+#include <vpp/app/version.h>
+#include <handoffdemo/handoffdemo.h>
+
+handoffdemo_main_t handoffdemo_main;
+
+/* *INDENT-OFF* */
+VLIB_PLUGIN_REGISTER () =
+{
+  .version = VPP_BUILD_VER,
+  .description = "handoff demo plugin",
+};
+/* *INDENT-ON* */
+
+/*
+ * fd.io coding-style-patch-verification: ON
+ *
+ * Local Variables:
+ * eval: (c-set-style "gnu")
+ * End:
+ */
diff --git a/src/examples/handoffdemo/handoffdemo.h b/src/examples/handoffdemo/handoffdemo.h
new file mode 100644
index 00000000000..558311fe29e
--- /dev/null
+++ b/src/examples/handoffdemo/handoffdemo.h
@@ -0,0 +1,50 @@
+
+/*
+ * handoffdemo.h - skeleton vpp engine plug-in header file
+ *
+ * Copyright (c) <current-year> <your-organization>
+ * 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_handoffdemo_h__
+#define __included_handoffdemo_h__
+
+#include <vnet/vnet.h>
+#include <vnet/ip/ip.h>
+#include <vnet/ethernet/ethernet.h>
+
+#include <vppinfra/hash.h>
+#include <vppinfra/error.h>
+
+typedef struct
+{
+  u32 frame_queue_index;
+
+
+  /* convenience */
+  vlib_main_t *vlib_main;
+  vnet_main_t *vnet_main;
+} handoffdemo_main_t;
+
+extern handoffdemo_main_t handoffdemo_main;
+
+extern vlib_node_registration_t handoffdemo_node_1, handoffdemo_node_2;
+
+#endif /* __included_handoffdemo_h__ */
+
+/*
+ * fd.io coding-style-patch-verification: ON
+ *
+ * Local Variables:
+ * eval: (c-set-style "gnu")
+ * End:
+ */
diff --git a/src/examples/handoffdemo/node.c b/src/examples/handoffdemo/node.c
new file mode 100644
index 00000000000..2177ccb9d14
--- /dev/null
+++ b/src/examples/handoffdemo/node.c
@@ -0,0 +1,241 @@
+/*
+ * node.c - skeleton vpp engine plug-in dual-loop node skeleton
+ *
+ * Copyright (c) <current-year> <your-organization>
+ * 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.
+ */
+#include <vlib/vlib.h>
+#include <vnet/vnet.h>
+#include <vnet/pg/pg.h>
+#include <vppinfra/error.h>
+#include <handoffdemo/handoffdemo.h>
+
+typedef struct
+{
+  int current_thread;
+} handoffdemo_trace_t;
+
+/* packet trace format function */
+static u8 *
+format_handoffdemo_trace (u8 * s, va_list * args)
+{
+  CLIB_UNUSED (vlib_main_t * vm) = va_arg (*args, vlib_main_t *);
+  CLIB_UNUSED (vlib_node_t * node) = va_arg (*args, vlib_node_t *);
+  handoffdemo_trace_t *t = va_arg (*args, handoffdemo_trace_t *);
+
+  s = format (s, "HANDOFFDEMO: current thread %d", t->current_thread);
+
+  return s;
+}
+
+vlib_node_registration_t handoffdemo_node;
+
+#define foreach_handoffdemo_error                       \
+_(HANDED_OFF, "packets handed off processed")           \
+_(CONGESTION_DROP, "handoff queue congestion drops")    \
+_(COMPLETE, "completed packets")
+
+typedef enum
+{
+#define _(sym,str) HANDOFFDEMO_ERROR_##sym,
+  foreach_handoffdemo_error
+#undef _
+    HANDOFFDEMO_N_ERROR,
+} handoffdemo_error_t;
+
+static char *handoffdemo_error_strings[] = {
+#define _(sym,string) string,
+  foreach_handoffdemo_error
+#undef _
+};
+
+typedef enum
+{
+  HANDOFFDEMO_NEXT_DROP,
+  HANDOFFDEMO_N_NEXT,
+} handoffdemo_next_t;
+
+always_inline uword
+handoffdemo_inline (vlib_main_t * vm,
+		    vlib_node_runtime_t * node, vlib_frame_t * frame,
+		    int which, int is_trace)
+{
+  handoffdemo_main_t *hmp = &handoffdemo_main;
+  u32 n_left_from, *from;
+  u32 error0 = node->errors[HANDOFFDEMO_ERROR_COMPLETE];
+  vlib_buffer_t *bufs[VLIB_FRAME_SIZE], **b;
+  u16 thread_indices[VLIB_FRAME_SIZE];
+  u16 nexts[VLIB_FRAME_SIZE], *next;
+  u32 n_enq;
+  int i;
+
+  from = vlib_frame_vector_args (frame);
+  n_left_from = frame->n_vectors;
+
+  vlib_get_buffers (vm, from, bufs, n_left_from);
+  next = nexts;
+  b = bufs;
+
+  /* First thread */
+  if (which == 1)
+    {
+      for (i = 0; i < frame->n_vectors; i++)
+	{
+	  /* Pick a thread to handle this packet */
+	  thread_indices[i] = 2;
+
+	  if (is_trace && (b[0]->flags & VLIB_BUFFER_IS_TRACED))
+	    {
+	      handoffdemo_trace_t *t = vlib_add_trace (vm, node, b[0],
+						       sizeof (*t));
+	      t->current_thread = vm->thread_index;
+	    }
+
+	  b += 1;
+	  next += 1;
+	  n_left_from -= 1;
+	}
+
+      /* Enqueue buffers to threads */
+      n_enq =
+	vlib_buffer_enqueue_to_thread (vm, hmp->frame_queue_index,
+				       from, thread_indices, frame->n_vectors,
+				       1 /* drop on congestion */ );
+      if (n_enq < frame->n_vectors)
+	vlib_node_increment_counter (vm, node->node_index,
+				     HANDOFFDEMO_ERROR_CONGESTION_DROP,
+				     frame->n_vectors - n_enq);
+      vlib_node_increment_counter (vm, node->node_index,
+				   HANDOFFDEMO_ERROR_HANDED_OFF, n_enq);
+      return frame->n_vectors;
+    }
+  else				/* Second thread */
+    {
+      u32 *from;
+
+      from = vlib_frame_vector_args (frame);
+      n_left_from = frame->n_vectors;
+
+      vlib_get_buffers (vm, from, bufs, n_left_from);
+      next = nexts;
+      b = bufs;
+
+      while (n_left_from > 0)
+	{
+	  if (is_trace && (b[0]->flags & VLIB_BUFFER_IS_TRACED))
+	    {
+	      handoffdemo_trace_t *t = vlib_add_trace (vm, node, b[0],
+						       sizeof (*t));
+	      t->current_thread = vm->thread_index;
+	    }
+
+	  next[0] = HANDOFFDEMO_NEXT_DROP;
+	  b[0]->error = error0;
+	  next++;
+	  b++;
+	  n_left_from--;
+	}
+
+      vlib_buffer_enqueue_to_next (vm, node, from, (u16 *) nexts,
+				   frame->n_vectors);
+    }
+
+  return frame->n_vectors;
+}
+
+static uword
+handoffdemo_node_1_fn (vlib_main_t * vm,
+		       vlib_node_runtime_t * node, vlib_frame_t * frame)
+{
+  if (PREDICT_FALSE (node->flags & VLIB_NODE_FLAG_TRACE))
+    return handoffdemo_inline (vm, node, frame, 1 /* which */ ,
+			       1 /* is_trace */ );
+  else
+    return handoffdemo_inline (vm, node, frame, 1 /* which */ ,
+			       0 /* is_trace */ );
+}
+
+/* *INDENT-OFF* */
+VLIB_REGISTER_NODE (handoffdemo_node_1) =
+{
+  .name = "handoffdemo-1",
+  .function = handoffdemo_node_1_fn,
+  .vector_size = sizeof (u32),
+  .format_trace = format_handoffdemo_trace,
+  .type = VLIB_NODE_TYPE_INTERNAL,
+
+  .n_errors = ARRAY_LEN(handoffdemo_error_strings),
+  .error_strings = handoffdemo_error_strings,
+
+  .n_next_nodes = HANDOFFDEMO_N_NEXT,
+
+  /* edit / add dispositions here */
+  .next_nodes = {
+        [HANDOFFDEMO_NEXT_DROP] = "error-drop",
+  },
+};
+/* *INDENT-ON* */
+
+uword
+handoffdemo_node_2_fn (vlib_main_t * vm,
+		       vlib_node_runtime_t * node, vlib_frame_t * frame)
+{
+  if (PREDICT_FALSE (node->flags & VLIB_NODE_FLAG_TRACE))
+    return handoffdemo_inline (vm, node, frame, 2 /* which */ ,
+			       1 /* is_trace */ );
+  else
+    return handoffdemo_inline (vm, node, frame, 2 /* which */ ,
+			       0 /* is_trace */ );
+}
+
+/* *INDENT-OFF* */
+VLIB_REGISTER_NODE (handoffdemo_node_2) =
+{
+  .name = "handoffdemo-2",
+  .function = handoffdemo_node_2_fn,
+  .vector_size = sizeof (u32),
+  .format_trace = format_handoffdemo_trace,
+  .type = VLIB_NODE_TYPE_INTERNAL,
+
+  .n_errors = ARRAY_LEN(handoffdemo_error_strings),
+  .error_strings = handoffdemo_error_strings,
+
+  .n_next_nodes = HANDOFFDEMO_N_NEXT,
+
+  /* edit / add dispositions here */
+  .next_nodes = {
+        [HANDOFFDEMO_NEXT_DROP] = "error-drop",
+  },
+};
+/* *INDENT-ON* */
+
+static clib_error_t *
+handoffdemo_node_init (vlib_main_t * vm)
+{
+  handoffdemo_main_t *hmp = &handoffdemo_main;
+
+  hmp->frame_queue_index = vlib_frame_queue_main_init
+    (handoffdemo_node_2.index, 16);
+
+  return 0;
+}
+
+VLIB_INIT_FUNCTION (handoffdemo_node_init);
+
+/*
+ * fd.io coding-style-patch-verification: ON
+ *
+ * Local Variables:
+ * eval: (c-set-style "gnu")
+ * End:
+ */