diff options
| author | Andrei Vagin <avagin@gmail.com> | 2019-11-12 04:26:58 +0300 |
|---|---|---|
| committer | Thomas Gleixner <tglx@linutronix.de> | 2020-01-14 14:20:51 +0300 |
| commit | 9c71a2e8a757bc6aee256bc97c6fb711144b0a0f (patch) | |
| tree | a0a11da36b1c82409506d496dc7b779b9d8bce27 /kernel/time/alarmtimer.c | |
| parent | 2f58bf909abf9670fa4e848b433dc12ba4c2a44e (diff) | |
| download | linux-9c71a2e8a757bc6aee256bc97c6fb711144b0a0f.tar.xz | |
posix-clocks: Introduce clock_get_ktime() callback
The callsite in common_timer_get() has already a comment:
/*
* The timespec64 based conversion is suboptimal, but it's not
* worth to implement yet another callback.
*/
kc->clock_get(timr->it_clock, &ts64);
now = timespec64_to_ktime(ts64);
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()
That adds a valid reason to finally implement a separate callback which
returns the time in ktime_t format.
Suggested-by: Thomas Gleixner <tglx@linutronix.de>
Co-developed-by: Dmitry Safonov <dima@arista.com>
Signed-off-by: Andrei Vagin <avagin@gmail.com>
Signed-off-by: Dmitry Safonov <dima@arista.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/r/20191112012724.250792-10-dima@arista.com
Diffstat (limited to 'kernel/time/alarmtimer.c')
| -rw-r--r-- | kernel/time/alarmtimer.c | 19 |
1 files changed, 18 insertions, 1 deletions
diff --git a/kernel/time/alarmtimer.c b/kernel/time/alarmtimer.c index 357be1fe6e1f..4d8c90546635 100644 --- a/kernel/time/alarmtimer.c +++ b/kernel/time/alarmtimer.c @@ -663,7 +663,7 @@ static int alarm_clock_getres(const clockid_t which_clock, struct timespec64 *tp * @which_clock: clockid * @tp: timespec to fill. * - * Provides the underlying alarm base time. + * Provides the underlying alarm base time in a tasks time namespace. */ static int alarm_clock_get_timespec(clockid_t which_clock, struct timespec64 *tp) { @@ -678,6 +678,22 @@ static int alarm_clock_get_timespec(clockid_t which_clock, struct timespec64 *tp } /** + * alarm_clock_get_ktime - posix clock_get_ktime interface + * @which_clock: clockid + * + * Provides the underlying alarm base time in the root namespace. + */ +static ktime_t alarm_clock_get_ktime(clockid_t which_clock) +{ + struct alarm_base *base = &alarm_bases[clock2alarm(which_clock)]; + + if (!alarmtimer_get_rtcdev()) + return -EINVAL; + + return base->get_ktime(); +} + +/** * alarm_timer_create - posix timer_create interface * @new_timer: k_itimer pointer to manage * @@ -840,6 +856,7 @@ static int alarm_timer_nsleep(const clockid_t which_clock, int flags, const struct k_clock alarm_clock = { .clock_getres = alarm_clock_getres, + .clock_get_ktime = alarm_clock_get_ktime, .clock_get_timespec = alarm_clock_get_timespec, .timer_create = alarm_timer_create, .timer_set = common_timer_set, |