load_gen: Supporting loading of load_gen via loader.

Currently all tools are loaded via loader utility, except load_gen.
Load_gens were loaded directly through component_factory.
This patch adds support to load load_gens through loader utility.

The changes are as follows:
1. Configuration changes:The common.conf include configuration of
   directory. testcases.conf includes changes to load configuration,
   where tool is no more part of the load-configuration. The
   custom.conf has configuration of LOADGEN to be used - this configuration
   replaces the earlier 'tool' configuration parameter.
2. loader_utility_changes:  In loader.py, loadgen_loader is
   defined, which is used in new get_loadgen function.
3. component_factory changes: in create_loadgen, similar
   to other tools, the function just retuns the object of loadgen_class.
4. Renaming of Dummy load_gen: Loader fails to load properly a dummy
   loadgen due to name-clash with dummy in pkt_gen. To avoid this name clash
   dummy is renamed to dummyloadgen.
5. testcase changes: create_loadgen is now called with output of
   loader's get_loadgen_class.
6. Fixed Pylint Errors and extra-space at the end.
7. Included CLI options support for --loadgen and --list-loadgens.
   Thanks to Martin K.
8. Added the missing loadgen parameter in testcases.conf.
9. Fixed the missing comma error.
10. Added CI change in build-vsperf.sh
11. Fixed configuration reading in stress/stress.py

JIRA: VSPERF-533

Change-Id: I3fbb259618825a12fef55320a748a4f02509190b
Signed-off-by: Sridhar K. N. Rao <sridhar.rao@spirent.com>
Signed-off-by: Martin Klozik <martinx.klozik@intel.com>

2 files changed, 27 insertions, 3 deletions

diff --git a/conf/01_testcases.conf b/conf/01_testcases.conf
index df582df9..bd5ba9eb 100755
--- a/conf/01_testcases.conf
+++ b/conf/01_testcases.conf
@@ -27,9 +27,12 @@
 #                                  # ip_port.
 # "Load": dictionary               # Optional. Configures background load
 #                                  # during testcase execution.
+#                                  # The tool used to generate load is
+#                                  # defined  by LOADGEN configuration.
+#                                  # Default setting of Dummy can be found in
+#                                  # 07_loadgen.conf.
 #   Description of "Load" dictionary keys, their meanings and available values:
 #
-#   "tool": "stress"               # One of the supported load generators.
 #   "load": 0-100                  # percentage of cores which should be
 #                                  # utilized by load generator
 #                                  # e.g. load = 70%, detected cpu cores = 14 =>
@@ -331,12 +334,12 @@ PERFORMANCE_TESTS = [
         "Deployment": "p2p",
         "Description": "LTD.CPU.RFC2544.0PacketLoss",
         "Load" : {
-            "tool" : "stress-ng",
             "load" : 100,
             "reserved" : 4,
             "pattern" : "c",
         },
         "Parameters" : {
+            "LOADGEN" : "StressNg",
             "TRAFFIC" : {
                 "traffic_type" : "rfc2544_throughput",
             },
@@ -347,12 +350,12 @@ PERFORMANCE_TESTS = [
         "Deployment": "p2p",
         "Description": "LTD.Memory.RFC2544.0PacketLoss",
         "Load" : {
-            "tool" : "stress-ng",
             "load" : 50,
             "pattern" : "m",
             "load_memory" : 80,
         },
         "Parameters" : {
+            "LOADGEN" : "StressNg",
             "TRAFFIC" : {
                 "traffic_type" : "rfc2544_throughput",
             },
diff --git a/conf/07_loadgen.conf b/conf/07_loadgen.conf
new file mode 100644
index 00000000..e7349a5d
--- /dev/null
+++ b/conf/07_loadgen.conf
@@ -0,0 +1,21 @@
+# Copyright 2015 Intel Corporation.
+#
+# 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.
+
+LOADGEN_DIR = os.path.join(ROOT_DIR, 'tools/load_gen')
+
+######################################################
+# LOADGEN tool: one of DummyLoadGen, Stress, StressNg
+######################################################
+LOADGEN = "DummyLoadGen"
+######################################################