CSIT-1139: Implement parallel test execution

The implementation of parallel test execution in VPP Test Framework.
- VPPTestCase test methods are grouped together
- tests are running in separate processes
- VPP instances spawned by tests are assigned to different cores
- output from these processes is redirected through pipes and printed
out testcase by testcase
- TEST_JOBS env var is used to specify the number of parallel processes
- improved test summary
- a bit of code cleanup

Change-Id: I9ca93904d9fe2c3daf980500c64a8611838ae28c
Signed-off-by: juraj.linkes <juraj.linkes@pantheon.tech>
diff --git a/test/Makefile b/test/Makefile
index 8af94f9..0338062 100644
--- a/test/Makefile
+++ b/test/Makefile
@@ -21,6 +21,12 @@
 FORCE_FOREGROUND=1
 else ifeq ($(DEBUG),core)
 FORCE_FOREGROUND=1
+else ifeq ($(STEP),yes)
+FORCE_FOREGROUND=1
+else ifeq ($(STEP),y)
+FORCE_FOREGROUND=1
+else ifeq ($(STEP),1)
+FORCE_FOREGROUND=1
 else
 FORCE_FOREGROUND=0
 endif
@@ -121,8 +127,25 @@
 SANITY_RUN_VPP_CMD=source $(PYTHON_VENV_PATH)/bin/activate && python sanity_run_vpp.py
 endif
 
+ifndef TEST_JOBS
+PARALLEL_ILLEGAL=0
+else ifeq ($(FORCE_FOREGROUND),0)
+PARALLEL_ILLEGAL=0
+else ifeq ($(TEST_JOBS),auto)
+PARALLEL_ILLEGAL=0
+else ifeq ($(TEST_JOBS),1)
+PARALLEL_ILLEGAL=0
+else
+PARALLEL_ILLEGAL=1
+endif
+
 sanity: verify-no-running-vpp
 	@sys_req/dev_shm_size.sh
+	@bash -c "test $(PARALLEL_ILLEGAL) -eq 0 ||\
+	    (echo \"*******************************************************************\" &&\
+		 echo \"* Sanity check failed, TEST_JOBS is not 1 or 'auto' and DEBUG, STEP or PROFILE is set\" &&\
+	         echo \"*******************************************************************\" &&\
+		 false)"
 	@bash -c "$(SANITY_IMPORT_VPP_PAPI_CMD) ||\
 		(echo \"*******************************************************************\" &&\
 		 echo \"* Sanity check failed, cannot import vpp_papi\" &&\
@@ -236,18 +259,19 @@
 	@echo ""
 	@echo "Arguments controlling test runs:"
 	@echo " V=[0|1|2]            - set test verbosity level"
+	@echo " TEST_JOBS=[<n>|auto] - use <n> parallel processes for test execution or automatic discovery of maximum acceptable processes (default: 1)"
 	@echo " CACHE_OUTPUT=[0|1]   - cache VPP stdout/stderr and log as one block after test finishes (default: 1)"
 	@echo " FAILFAST=[0|1]       - fail fast if 1, complete all tests if 0"
-	@echo " TIMEOUT=<timeout>    - fail test suite if any single test takes longer than <timeout> (in seconds) to finish"
+	@echo " TIMEOUT=<timeout>    - fail test suite if any single test takes longer than <timeout> (in seconds) to finish (default: 600)"
 	@echo " RETRIES=<n>          - retry failed tests <n> times"
 	@echo " DEBUG=<type>         - set VPP debugging kind"
 	@echo "    DEBUG=core        - detect coredump and load it in gdb on crash"
-	@echo "    DEBUG=gdb         - allow easy debugging by printing VPP PID "
-	@echo "                        and waiting for user input before running "
+	@echo "    DEBUG=gdb         - allow easy debugging by printing VPP PID"
+	@echo "                        and waiting for user input before running"
 	@echo "                        and tearing down a testcase"
-	@echo "    DEBUG=gdbserver   - run gdb inside a gdb server, otherwise "
+	@echo "    DEBUG=gdbserver   - run gdb inside a gdb server, otherwise"
 	@echo "                        same as above"
-	@echo " STEP=[yes|no]        - ease debugging by stepping through a testcase "
+	@echo " STEP=[yes|no]        - ease debugging by stepping through a testcase"
 	@echo " SANITY=[yes|no]      - perform sanity import of vpp-api/sanity vpp run before running tests (default: yes)"
 	@echo " EXTENDED_TESTS=[1|y] - run extended tests"
 	@echo " TEST=<filter>        - filter the set of tests:"