Merge pull request #6735 from smlng/tests/xtimer_now64_cont

tests: enhance xtimer_now64_continuity

tests/xtimer_now64_continuity/Makefile

@@ -1,6 +1,7 @@
 APPLICATION = xtimer_now64_continuity
 include ../Makefile.tests_common
 
+USEMODULE += fmt
 USEMODULE += xtimer
 
 include $(RIOTBASE)/Makefile.include

tests/xtimer_now64_continuity/README.md

@@ -1,5 +1,6 @@
 Description
 ===========
 
-This test measures the difference of two consecutive calls to xtimer_now64() 10k times.
-Should the difference be larger then 1000us, the test fails, otherwise it succeeds.
+This test measures the difference of two consecutive calls to xtimer_now64()
+100k times. If the max or average difference is larger than 1000us the test
+fails, otherwise it succeeds.

tests/xtimer_now64_continuity/main.c

@@ -1,5 +1,6 @@
 /*
  * Copyright (C) 2015 Kaspar Schleiser <kaspar@schleiser.de>
+ *               2017 HAW Hamburg
  *
  * This file is subject to the terms and conditions of the GNU Lesser
  * General Public License v2.1. See the file LICENSE in the top level
@@ -14,35 +15,50 @@
  * @brief       xtimer_now64 continuity test application
  *
  * @author      Kaspar Schleiser <kaspar@schleiser.de>
+ * @author      Sebastian Meiling <s@mlng.net>
  *
  * @}
  */
 
-#include <stdio.h>
 #include <stdint.h>
 
 #include "xtimer.h"
+#include "fmt.h"
 
-#define ITERATIONS (100000LU)
-#define MAXDIFF 1000
+#define ITERATIONS  (100000LU)
+#define MAXDIFF     (1000U)
 
 int main(void)
 {
     uint32_t n = ITERATIONS;
-    uint64_t before = _xtimer_now64();
-
+    uint64_t diff_min = UINT64_MAX;
+    uint64_t diff_max = 0;
+    uint64_t diff_sum = 0;
+    xtimer_ticks64_t before = xtimer_now64();
+    print_str("[START]\n");
     while(--n) {
-        uint64_t now = _xtimer_now64();
-        if ((now-before) > MAXDIFF) {
-            puts("TEST FAILED.");
-            break;
+        xtimer_ticks64_t now = xtimer_now64();
+        xtimer_ticks64_t diff = xtimer_diff64(now, before);
+        if (diff.ticks64 > diff_max) {
+            diff_max = diff.ticks64;
+        }
+        if (diff.ticks64 < diff_min) {
+            diff_min = diff.ticks64;
         }
+        diff_sum += diff.ticks64;
         before = now;
     }
-
-    if (!n) {
-        puts("TEST SUCCESSFUL.");
+    print_str("[RESULTS] min=");
+    print_u64_dec(diff_min);
+    print_str(", avg=");
+    print_u64_dec(diff_sum/ITERATIONS);
+    print_str(", max=");
+    print_u64_dec(diff_max);
+    print_str("\n");
+    if ((diff_max > MAXDIFF) || (diff_sum/ITERATIONS > MAXDIFF)) {
+        print_str("[FAILURE]\n");
+        return 1;
     }
-
+    print_str("[SUCCESS]\n");
     return 0;
 }