1 files changed, 107 insertions, 0 deletions

diff --git a/tools/testing/selftests/timers/change_skew.c b/tools/testing/selftests/timers/change_skew.c
new file mode 100644
index 000000000000..cb1968977c04
--- /dev/null
+++ b/tools/testing/selftests/timers/change_skew.c
@@ -0,0 +1,107 @@
+/* ADJ_FREQ Skew change test
+ *              by: john stultz (johnstul@us.ibm.com)
+ *              (C) Copyright IBM 2012
+ *              Licensed under the GPLv2
+ *
+ *  NOTE: This is a meta-test which cranks the ADJ_FREQ knob and
+ *  then uses other tests to detect problems. Thus this test requires
+ *  that the raw_skew, inconsistency-check and nanosleep tests be
+ *  present in the same directory it is run from.
+ *
+ *  To build:
+ *      $ gcc change_skew.c -o change_skew -lrt
+ *
+ *   This program is free software: you can redistribute it and/or modify
+ *   it under the terms of the GNU General Public License as published by
+ *   the Free Software Foundation, either version 2 of the License, or
+ *   (at your option) any later version.
+ *
+ *   This program is distributed in the hope that it will be useful,
+ *   but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *   GNU General Public License for more details.
+ */
+
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <sys/time.h>
+#include <sys/timex.h>
+#include <time.h>
+#ifdef KTEST
+#include "../kselftest.h"
+#else
+static inline int ksft_exit_pass(void)
+{
+        exit(0);
+}
+static inline int ksft_exit_fail(void)
+{
+        exit(1);
+}
+#endif
+
+#define NSEC_PER_SEC 1000000000LL
+
+
+int change_skew_test(int ppm)
+{
+        struct timex tx;
+        int ret;
+
+        tx.modes = ADJ_FREQUENCY;
+        tx.freq = ppm << 16;
+
+        ret = adjtimex(&tx);
+        if (ret < 0) {
+                printf("Error adjusting freq\n");
+                return ret;
+        }
+
+        ret = system("./raw_skew");
+        ret |= system("./inconsistency-check");
+        ret |= system("./nanosleep");
+
+        return ret;
+}
+
+
+int main(int argv, char **argc)
+{
+        struct timex tx;
+        int i, ret;
+
+        int ppm[5] = {0, 250, 500, -250, -500};
+
+        /* Kill ntpd */
+        ret = system("killall -9 ntpd");
+
+        /* Make sure there's no offset adjustment going on */
+        tx.modes = ADJ_OFFSET;
+        tx.offset = 0;
+        ret = adjtimex(&tx);
+
+        if (ret < 0) {
+                printf("Maybe you're not running as root?\n");
+                return -1;
+        }
+
+        for (i = 0; i < 5; i++) {
+                printf("Using %i ppm adjustment\n", ppm[i]);
+                ret = change_skew_test(ppm[i]);
+                if (ret)
+                        break;
+        }
+
+        /* Set things back */
+        tx.modes = ADJ_FREQUENCY;
+        tx.offset = 0;
+        adjtimex(&tx);
+
+        if (ret) {
+                printf("[FAIL]");
+                return ksft_exit_fail();
+        }
+        printf("[OK]");
+        return ksft_exit_pass();
+}