From: Andrei Vagin Date: Tue, 12 Nov 2019 01:26:58 +0000 (+0000) Subject: posix-clocks: Introduce clock_get_ktime() callback X-Git-Tag: v5.6-rc1~177^2~35 X-Git-Url: https://asedeno.scripts.mit.edu/gitweb/?a=commitdiff_plain;h=9c71a2e8a757bc6aee256bc97c6fb711144b0a0f;p=linux.git 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 Co-developed-by: Dmitry Safonov Signed-off-by: Andrei Vagin Signed-off-by: Dmitry Safonov Signed-off-by: Thomas Gleixner Link: https://lore.kernel.org/r/20191112012724.250792-10-dima@arista.com --- 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) { @@ -677,6 +677,22 @@ static int alarm_clock_get_timespec(clockid_t which_clock, struct timespec64 *tp return 0; } +/** + * 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, diff --git a/kernel/time/posix-timers.c b/kernel/time/posix-timers.c index 68d4690cc225..a1f6b968c5d8 100644 --- a/kernel/time/posix-timers.c +++ b/kernel/time/posix-timers.c @@ -171,6 +171,11 @@ static int posix_get_realtime_timespec(clockid_t which_clock, struct timespec64 return 0; } +static ktime_t posix_get_realtime_ktime(clockid_t which_clock) +{ + return ktime_get_real(); +} + /* Set clock_realtime */ static int posix_clock_realtime_set(const clockid_t which_clock, const struct timespec64 *tp) @@ -193,6 +198,11 @@ static int posix_get_monotonic_timespec(clockid_t which_clock, struct timespec64 return 0; } +static ktime_t posix_get_monotonic_ktime(clockid_t which_clock) +{ + return ktime_get(); +} + /* * Get monotonic-raw time for posix timers */ @@ -228,12 +238,22 @@ static int posix_get_boottime_timespec(const clockid_t which_clock, struct times return 0; } +static ktime_t posix_get_boottime_ktime(const clockid_t which_clock) +{ + return ktime_get_boottime(); +} + static int posix_get_tai_timespec(clockid_t which_clock, struct timespec64 *tp) { ktime_get_clocktai_ts64(tp); return 0; } +static ktime_t posix_get_tai_ktime(clockid_t which_clock) +{ + return ktime_get_clocktai(); +} + static int posix_get_hrtimer_res(clockid_t which_clock, struct timespec64 *tp) { tp->tv_sec = 0; @@ -781,7 +801,7 @@ static void common_hrtimer_arm(struct k_itimer *timr, ktime_t expires, * Posix magic: Relative CLOCK_REALTIME timers are not affected by * clock modifications, so they become CLOCK_MONOTONIC based under the * hood. See hrtimer_init(). Update timr->kclock, so the generic - * functions which use timr->kclock->clock_get_timespec() work. + * functions which use timr->kclock->clock_get_*() work. * * Note: it_clock stays unmodified, because the next timer_set() might * use ABSTIME, so it needs to switch back. @@ -1262,6 +1282,7 @@ SYSCALL_DEFINE4(clock_nanosleep_time32, clockid_t, which_clock, int, flags, static const struct k_clock clock_realtime = { .clock_getres = posix_get_hrtimer_res, .clock_get_timespec = posix_get_realtime_timespec, + .clock_get_ktime = posix_get_realtime_ktime, .clock_set = posix_clock_realtime_set, .clock_adj = posix_clock_realtime_adj, .nsleep = common_nsleep, @@ -1280,6 +1301,7 @@ static const struct k_clock clock_realtime = { static const struct k_clock clock_monotonic = { .clock_getres = posix_get_hrtimer_res, .clock_get_timespec = posix_get_monotonic_timespec, + .clock_get_ktime = posix_get_monotonic_ktime, .nsleep = common_nsleep, .timer_create = common_timer_create, .timer_set = common_timer_set, @@ -1310,6 +1332,7 @@ static const struct k_clock clock_monotonic_coarse = { static const struct k_clock clock_tai = { .clock_getres = posix_get_hrtimer_res, + .clock_get_ktime = posix_get_tai_ktime, .clock_get_timespec = posix_get_tai_timespec, .nsleep = common_nsleep, .timer_create = common_timer_create, @@ -1326,6 +1349,7 @@ static const struct k_clock clock_tai = { static const struct k_clock clock_boottime = { .clock_getres = posix_get_hrtimer_res, + .clock_get_ktime = posix_get_boottime_ktime, .clock_get_timespec = posix_get_boottime_timespec, .nsleep = common_nsleep, .timer_create = common_timer_create, diff --git a/kernel/time/posix-timers.h b/kernel/time/posix-timers.h index 070611b2c253..f32a2ebba9b8 100644 --- a/kernel/time/posix-timers.h +++ b/kernel/time/posix-timers.h @@ -6,8 +6,11 @@ struct k_clock { struct timespec64 *tp); int (*clock_set)(const clockid_t which_clock, const struct timespec64 *tp); + /* Returns the clock value in the current time namespace. */ int (*clock_get_timespec)(const clockid_t which_clock, struct timespec64 *tp); + /* Returns the clock value in the root time namespace. */ + ktime_t (*clock_get_ktime)(const clockid_t which_clock); int (*clock_adj)(const clockid_t which_clock, struct __kernel_timex *tx); int (*timer_create)(struct k_itimer *timer); int (*nsleep)(const clockid_t which_clock, int flags,