time: Avoid timespec in udelay_test

udelay_test_single() uses ktime_get_ts() to get two timespec values
and calculate the difference between them, while udelay_test_show()
uses the same to printk() the current monotonic time.

Both of these are y2038 safe on all machines, but we want to
get rid of struct timespec anyway, so this converts the code to
use ktime_get_ns() and ktime_get_ts64() respectively.

Cc: Prarit Bhargava <prarit@redhat.com>
Cc: Richard Cochran <richardcochran@gmail.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: John Stultz <john.stultz@linaro.org>

diff --git a/kernel/time/test_udelay.c b/kernel/time/test_udelay.c
index e622ba365a131a445bbfce4c4df860ad50afae48..b0928ab3270fb6d7666c6309eeb5f9dca014b91e 100644 (file)
--- a/kernel/time/test_udelay.c
+++ b/kernel/time/test_udelay.c
@@ -43,13 +43,13 @@ static int udelay_test_single(struct seq_file *s, int usecs, uint32_t iters)
        int allowed_error_ns = usecs * 5;
 
        for (i = 0; i < iters; ++i) {
-               struct timespec ts1, ts2;
+               s64 kt1, kt2;
                int time_passed;
 
-               ktime_get_ts(&ts1);
+               kt1 = ktime_get_ns();
                udelay(usecs);
-               ktime_get_ts(&ts2);
-               time_passed = timespec_to_ns(&ts2) - timespec_to_ns(&ts1);
+               kt2 = ktime_get_ns();
+               time_passed = kt2 - kt1;
 
                if (i == 0 || time_passed < min)
                        min = time_passed;
@@ -87,11 +87,11 @@ static int udelay_test_show(struct seq_file *s, void *v)
        if (usecs > 0 && iters > 0) {
                return udelay_test_single(s, usecs, iters);
        } else if (usecs == 0) {
-               struct timespec ts;
+               struct timespec64 ts;
 
-               ktime_get_ts(&ts);
-               seq_printf(s, "udelay() test (lpj=%ld kt=%ld.%09ld)\n",
-                               loops_per_jiffy, ts.tv_sec, ts.tv_nsec);
+               ktime_get_ts64(&ts);
+               seq_printf(s, "udelay() test (lpj=%ld kt=%lld.%09ld)\n",
+                               loops_per_jiffy, (s64)ts.tv_sec, ts.tv_nsec);
                seq_puts(s, "usage:\n");
                seq_puts(s, "echo USECS [ITERS] > " DEBUGFS_FILENAME "\n");
                seq_puts(s, "cat " DEBUGFS_FILENAME "\n");