pg: fix the buffer deletion

Type: fix

Signed-off-by: Mohsin Kazmi <sykazmi@cisco.com>
Change-Id: I8f0a67706399dad1e5296aafd1cfa92958b2fe82

2 files changed, 134 insertions, 11 deletions

diff --git a/src/vnet/pg/pg.h b/src/vnet/pg/pg.h
index 5e99d9af9f6..5e63b58caf6 100644
--- a/src/vnet/pg/pg.h
+++ b/src/vnet/pg/pg.h
@@ -182,14 +182,38 @@ typedef struct pg_stream_t
 } pg_stream_t;
 
 always_inline void
-pg_buffer_index_free (pg_buffer_index_t * bi)
+pg_free_buffers (pg_buffer_index_t *bi)
 {
   vlib_main_t *vm = vlib_get_main ();
-  word n_alloc;
-  vec_free (bi->edits);
-  n_alloc = clib_fifo_elts (bi->buffer_fifo);
-  vlib_buffer_free (vm, bi->buffer_fifo, n_alloc);
-  clib_fifo_free (bi->buffer_fifo);
+  uword n_elts, head, len;
+
+  if (!bi || !bi->buffer_fifo)
+    return;
+
+  n_elts = clib_fifo_elts (bi->buffer_fifo);
+  if (n_elts)
+    {
+      len = clib_fifo_len (bi->buffer_fifo);
+      head = clib_fifo_head_index (bi->buffer_fifo);
+
+      if (head + n_elts <= len)
+	vlib_buffer_free (vm, &bi->buffer_fifo[head], n_elts);
+      else
+	{
+	  vlib_buffer_free (vm, &bi->buffer_fifo[head], len - head);
+	  vlib_buffer_free (vm, bi->buffer_fifo, n_elts - (len - head));
+	}
+    }
+}
+
+always_inline void
+pg_buffer_index_free (pg_buffer_index_t *bi)
+{
+  if (bi)
+    {
+      vec_free (bi->edits);
+      clib_fifo_free (bi->buffer_fifo);
+    }
 }
 
 always_inline void
@@ -220,11 +244,16 @@ pg_stream_free (pg_stream_t * s)
   vec_free (s->replay_packet_templates);
   vec_free (s->replay_packet_timestamps);
 
-  {
-    pg_buffer_index_t *bi;
-    vec_foreach (bi, s->buffer_indices) pg_buffer_index_free (bi);
-    vec_free (s->buffer_indices);
-  }
+  if (s->buffer_indices)
+    {
+      pg_buffer_index_t *bi;
+      // We only need to free the buffers from the first array, as the buffers
+      // are chained when packet-generator enable is issued.
+      pg_free_buffers (s->buffer_indices);
+      vec_foreach (bi, s->buffer_indices)
+	pg_buffer_index_free (bi);
+      vec_free (s->buffer_indices);
+    }
 }
 
 always_inline int
diff --git a/test/test_pg_stream.py b/test/test_pg_stream.py
new file mode 100644
index 00000000000..6c01d3b7b16
--- /dev/null
+++ b/test/test_pg_stream.py
@@ -0,0 +1,94 @@
+#!/usr/bin/env python3
+
+import unittest
+
+from scapy.packet import Raw
+from scapy.layers.l2 import Ether
+from scapy.layers.inet import IP, UDP
+from scapy.layers.inet6 import IPv6
+
+from framework import VppTestCase
+from asfframework import VppTestRunner
+
+
+class TestPgStream(VppTestCase):
+    """PG Stream Test Case"""
+
+    def __init__(self, *args):
+        VppTestCase.__init__(self, *args)
+
+    def setUp(self):
+        super(TestPgStream, self).setUp()
+
+        # Create 3 pg interfaces - one each for ethernet, IPv4, and IPv6.
+        self.create_pg_interfaces(range(0, 1))
+        self.pg_interfaces += self.create_pg_ip4_interfaces(range(1, 2))
+        self.pg_interfaces += self.create_pg_ip6_interfaces(range(2, 3))
+
+        for i in self.pg_interfaces:
+            i.admin_up()
+
+        for i in [self.pg0, self.pg1]:
+            i.config_ip4()
+
+        for i in [self.pg0, self.pg2]:
+            i.config_ip6()
+
+        self.pg0.resolve_arp()
+        self.pg0.resolve_ndp()
+
+    def tearDown(self):
+        super(TestPgStream, self).tearDown()
+        for i in self.pg_interfaces:
+            i.unconfig_ip4()
+            i.admin_down()
+            i.remove_vpp_config()
+
+    def pg_stream(self, count=100, rate=1e6, packet_size=700):
+        rate = str(rate)
+        packet_size = str(packet_size)
+        count = str(count)
+
+        cmds = [
+            "packet-generator new {{\n"
+            "  name pg0-stream\n"
+            "  limit {count}\n"
+            "  node ethernet-input\n"
+            "  source pg0\n"
+            "  rate {rate}\n"
+            "  size {packet_size}+{packet_size}\n"
+            "  data {{\n"
+            "    IP4: {src_mac} -> 00:02:03:04:05:06\n"
+            "    UDP: 192.168.20.20 -> 192.168.10.100\n"
+            "    UDP: 1234 -> 4321\n"
+            "    incrementing 100\n"
+            "  }}\n"
+            "}}\n".format(
+                count=count,
+                rate=rate,
+                packet_size=packet_size,
+                src_mac=self.pg0.local_mac,
+            ),
+            "packet-generator enable",
+            "packet-generator disable",
+            "packet-generator delete pg0-stream",
+        ]
+
+        for cmd in cmds:
+            r = self.vapi.cli_return_response(cmd)
+            if r.retval != 0:
+                if hasattr(r, "reply"):
+                    self.logger.info(cmd + " FAIL reply " + r.reply)
+                else:
+                    self.logger.info(cmd + " FAIL retval " + str(r.retval))
+
+    def test_pg_stream(self):
+        """PG Stream testing"""
+        self.pg_stream(rate=100, packet_size=64)
+        self.pg_stream(count=1000, rate=1000)
+        self.pg_stream(count=100000, rate=10000, packet_size=1500)
+        self.pg_stream(packet_size=4000)
+
+
+if __name__ == "__main__":
+    unittest.main(testRunner=VppTestRunner)