test: add procfs error message for multi-process launch

Currently, if there is no procfs mounted, test application will
fail to run any multiprocess-related autotests (EAL flags etc.)
without a clear explanation as to why this happens.

Add a check specifically for that condition, as well as add a
general stringified error message to rte_panic.

Signed-off-by: Anatoly Burakov <anatoly.burakov@intel.com>

diff --git a/app/test/process.h b/app/test/process.h
index 513bc94..128ce41 100644 (file)
--- a/app/test/process.h
+++ b/app/test/process.h
@@ -5,12 +5,16 @@
 #ifndef _PROCESS_H_
 #define _PROCESS_H_
 
+#include <errno.h>  /* errno */
 #include <limits.h> /* PATH_MAX */
 #include <libgen.h> /* basename et al */
 #include <stdlib.h> /* NULL */
+#include <string.h> /* strerror */
 #include <unistd.h> /* readlink */
 #include <sys/wait.h>
 
+#include <rte_string_fns.h> /* strlcpy */
+
 #ifdef RTE_EXEC_ENV_FREEBSD
 #define self "curproc"
 #define exe "file"
@@ -67,8 +71,15 @@ process_dup(const char *const argv[], int numargs, const char *env_value)
                /* set the environment variable */
                if (setenv(RECURSIVE_ENV_VAR, env_value, 1) != 0)
                        rte_panic("Cannot export environment variable\n");
-               if (execv("/proc/" self "/" exe, argv_cpy) < 0)
-                       rte_panic("Cannot exec\n");
+
+               strlcpy(path, "/proc/" self "/" exe, sizeof(path));
+               if (execv(path, argv_cpy) < 0) {
+                       if (errno == ENOENT) {
+                               printf("Could not find '%s', is procfs mounted?\n",
+                                               path);
+                       }
+                       rte_panic("Cannot exec: %s\n", strerror(errno));
+               }
        }
        /* parent process does a wait */
 #ifdef RTE_LIBRTE_PDUMP