[dpdk-dev] [PATCH] test/test: allow taking extra arguments from environment

[Bruce Richardson <bruce.richardson@intel.com>]

When running unit tests automatically, either via script, from meson,
or otherwise, the same set of options may be used for each run, for
example to set a standard coremask to be used for all tests.

To facilitate this, this patch adds support for the test binary taking
additional EAL parameters from the environment and appending them to the
argc/argv list passed to eal init. This allows parameter modification
without having to edit test scripts etc.

There are now two environment variables which can be used for running
tests:
 * DPDK_TEST - (added previously) passes the test name to be run
               automatically rather than running the app interactively.
               Used by "meson test" when running tests individually or
               as part of a suite.

 * DPDK_TEST_PARAMS - new parameter to specify the commandline arguments
               to use with the test binary. For example to run a test,
               or tests, on only 16 lcores, and to skip pci scan we can
               set this to "-l 0-15 --no-pci".

Signed-off-by: Bruce Richardson <bruce.richardson@intel.com>
---
 doc/guides/rel_notes/release_18_11.rst |  8 ++++++
 test/test/test.c                       | 34 +++++++++++++++++++++++++-
 2 files changed, 41 insertions(+), 1 deletion(-)

diff --git a/doc/guides/rel_notes/release_18_11.rst b/doc/guides/rel_notes/release_18_11.rst
index 436b20e2b..b5ac61e55 100644
--- a/doc/guides/rel_notes/release_18_11.rst
+++ b/doc/guides/rel_notes/release_18_11.rst
@@ -159,6 +159,14 @@ New Features
   this application doesn't need to launch dedicated worker threads for vhost
   enqueue/dequeue operations.
 
+* **Allow Unit Test Binary to take Parameters from the environment**
+
+  The unit test "test", or "dpdk-test", binary is often called from scripts,
+  which can make passing additional parameters, such as a coremask, to it more
+  awkward. Support has been added to the application to allow it to take
+  additional command-line parameter values from the "DPDK_TEST_PARAMS"
+  environment variable to make this application easier to use.
+
 
 API Changes
 -----------
diff --git a/test/test/test.c b/test/test/test.c
index 44dfe20ef..d49700d7f 100644
--- a/test/test/test.c
+++ b/test/test/test.c
@@ -75,15 +75,47 @@ do_recursive_call(void)
 
 int last_test_result;
 
+#define MAX_EXTRA_ARGS 32
+
 int
 main(int argc, char **argv)
 {
 #ifdef RTE_LIBRTE_CMDLINE
 	struct cmdline *cl;
 #endif
+	char *extra_args;
 	int ret;
 
-	ret = rte_eal_init(argc, argv);
+	extra_args = getenv("DPDK_TEST_PARAMS");
+	if (extra_args != NULL && strlen(extra_args) > 0) {
+		char **all_argv;
+		char *eargv[MAX_EXTRA_ARGS];
+		int all_argc;
+		int eargc;
+		int i;
+
+		RTE_LOG(INFO, APP, "Using additional DPDK_TEST_PARAMS: '%s'\n",
+				extra_args);
+		eargc = rte_strsplit(extra_args, strlen(extra_args),
+				eargv, MAX_EXTRA_ARGS, ' ');
+
+		/* merge argc/argv and the environment args */
+		all_argc = argc + eargc;
+		all_argv = malloc(sizeof(*all_argv) * (all_argc + 1));
+		if (all_argv == NULL)
+			return -1;
+
+		for (i = 0; i < argc; i++)
+			all_argv[i] = argv[i];
+		for (i = 0; i < eargc; i++)
+			all_argv[argc + i] = eargv[i];
+		all_argv[all_argc] = NULL;
+
+		/* call eal_init with combined args */
+		ret = rte_eal_init(all_argc, all_argv);
+		free(all_argv);
+	} else
+		ret = rte_eal_init(argc, argv);
 	if (ret < 0)
 		return -1;
 
-- 
2.17.2