[PATCHv8 08/34] alarmtimer: Provide get_timespec() callback

Dmitry Safonov
2019-11-12T01:26:57Z

From: Andrei Vagin <avagin@gmail.com>

The upcoming support for time namespaces requires to have access to:
- The time in a task's time namespace for sys_clock_gettime()
- The time in the root name space for common_timer_get()

Wire up alarm bases with get_timespec().

Suggested-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Andrei Vagin <avagin@gmail.com>
Co-developed-by: Dmitry Safonov <dima@arista.com>
Signed-off-by: Dmitry Safonov <dima@arista.com>
---
kernel/time/alarmtimer.c | 7 ++++++-
1 file changed, 6 insertions(+), 1 deletion(-)

diff --git a/kernel/time/alarmtimer.c b/kernel/time/alarmtimer.c
index 22b6f9b133b2..357be1fe6e1f 100644
--- a/kernel/time/alarmtimer.c
+++ b/kernel/time/alarmtimer.c
@@ -37,12 +37,14 @@
* @lock: Lock for syncrhonized access to the base
* @timerqueue: Timerqueue head managing the list of events
* @get_ktime: Function to read the time correlating to the base
+ * @get_timespec: Function to read the namespace time correlating to the base
* @base_clockid: clockid for the base
*/
static struct alarm_base {
spinlock_t lock;
struct timerqueue_head timerqueue;
ktime_t (*get_ktime)(void);
+ void (*get_timespec)(struct timespec64 *tp);
clockid_t base_clockid;
} alarm_bases[ALARM_NUMTYPE];

@@ -670,7 +672,8 @@ static int alarm_clock_get_timespec(clockid_t which_clock, struct timespec64 *tp
if (!alarmtimer_get_rtcdev())
return -EINVAL;

- *tp = ktime_to_timespec64(base->get_ktime());
+ base->get_timespec(tp);
+
return 0;
}

@@ -883,8 +886,10 @@ static int __init alarmtimer_init(void)
/* Initialize alarm bases */
alarm_bases[ALARM_REALTIME].base_clockid = CLOCK_REALTIME;
alarm_bases[ALARM_REALTIME].get_ktime = &ktime_get_real;
+ alarm_bases[ALARM_REALTIME].get_timespec = ktime_get_real_ts64,
alarm_bases[ALARM_BOOTTIME].base_clockid = CLOCK_BOOTTIME;
alarm_bases[ALARM_BOOTTIME].get_ktime = &ktime_get_boottime;
+ alarm_bases[ALARM_BOOTTIME].get_timespec = ktime_get_boottime_ts64;
for (i = 0; i < ALARM_NUMTYPE; i++) {
timerqueue_init_head(&alarm_bases[i].timerqueue);
spin_lock_init(&alarm_bases[i].lock);
--
2.24.0