[PATCH v4 03/25] time/hrtimer:Introduce hrtimer_get_res64() with timespec64 type

[Baolin Wang <baolin.wang@linaro.org>]

This patch introduces hrtimer_get_res64() function to get the timer
resolution with timespec64 type, and moves the hrtimer_get_res()
function into include/linux/hrtimer.h as a 'static inline' helper that
just calls hrtimer_get_res64.

It is ready for 2038 year when getting the timer resolution by hrtimer_get_res64()
function with timespec64 type, and it is convenient to remove the old
hrtimer_get_res() function in hrtimer.h file.

Signed-off-by: Baolin Wang <baolin.wang@linaro.org>
---
 include/linux/hrtimer.h |   16 +++++++++++++++-
 kernel/time/hrtimer.c   |   10 +++++-----
 2 files changed, 20 insertions(+), 6 deletions(-)

diff --git a/include/linux/hrtimer.h b/include/linux/hrtimer.h
index 05f6df1..17e9294 100644
--- a/include/linux/hrtimer.h
+++ b/include/linux/hrtimer.h
@@ -383,7 +383,21 @@ static inline int hrtimer_restart(struct hrtimer *timer)
 
 /* Query timers: */
 extern ktime_t hrtimer_get_remaining(const struct hrtimer *timer);
-extern int hrtimer_get_res(const clockid_t which_clock, struct timespec *tp);
+extern int hrtimer_get_res64(const clockid_t which_clock,
+			     struct timespec64 *tp);
+
+static inline int hrtimer_get_res(const clockid_t which_clock,
+				  struct timespec *tp)
+{
+	struct timespec64 ts64;
+	int ret;
+
+	ret = hrtimer_get_res64(which_clock, &ts64);
+	if (!ret)
+		*tp = timespec64_to_timespec(ts64);
+
+	return ret;
+}
 
 extern ktime_t hrtimer_get_next_event(void);
 
diff --git a/kernel/time/hrtimer.c b/kernel/time/hrtimer.c
index bee0c1f..508d936 100644
--- a/kernel/time/hrtimer.c
+++ b/kernel/time/hrtimer.c
@@ -1175,24 +1175,24 @@ void hrtimer_init(struct hrtimer *timer, clockid_t clock_id,
 EXPORT_SYMBOL_GPL(hrtimer_init);
 
 /**
- * hrtimer_get_res - get the timer resolution for a clock
+ * hrtimer_get_res64 - get the timer resolution for a clock
  * @which_clock: which clock to query
- * @tp:		 pointer to timespec variable to store the resolution
+ * @tp:		 pointer to timespec64 variable to store the resolution
  *
  * Store the resolution of the clock selected by @which_clock in the
  * variable pointed to by @tp.
  */
-int hrtimer_get_res(const clockid_t which_clock, struct timespec *tp)
+int hrtimer_get_res64(const clockid_t which_clock, struct timespec64 *tp)
 {
 	struct hrtimer_cpu_base *cpu_base;
 	int base = hrtimer_clockid_to_base(which_clock);
 
 	cpu_base = raw_cpu_ptr(&hrtimer_bases);
-	*tp = ktime_to_timespec(cpu_base->clock_base[base].resolution);
+	*tp = ktime_to_timespec64(cpu_base->clock_base[base].resolution);
 
 	return 0;
 }
-EXPORT_SYMBOL_GPL(hrtimer_get_res);
+EXPORT_SYMBOL_GPL(hrtimer_get_res64);
 
 static void __run_hrtimer(struct hrtimer *timer, ktime_t *now)
 {
-- 
1.7.9.5