timers: Add CLOCK_BOOTTIME hrtimer base
CLOCK_MONOTONIC stops while the system is in suspend. This is because
to applications system suspend is invisible. However, there is a
growing set of applications that are wanting to be suspend-aware,
but do not want to deal with the complications of CLOCK_REALTIME
(which might jump around if settimeofday is called).
For these applications, I propose a new clockid: CLOCK_BOOTTIME.
CLOCK_BOOTTIME is idential to CLOCK_MONOTONIC, except it also
includes any time spent in suspend.
This patch add hrtimer base for CLOCK_BOOTTIME, using
get_monotonic_boottime/ktime_get_boottime, to allow
in kernel users to set timers against.
CC: Jamie Lokier <jamie@shareable.org>
CC: Thomas Gleixner <tglx@linutronix.de>
CC: Alexander Shishkin <virtuoso@slind.org>
CC: Arve Hjønnevåg <arve@android.com>
Signed-off-by: John Stultz <john.stultz@linaro.org>
diff --git a/kernel/hrtimer.c b/kernel/hrtimer.c
index e8bf3ad..4c53af1 100644
--- a/kernel/hrtimer.c
+++ b/kernel/hrtimer.c
@@ -73,6 +73,11 @@
.get_time = &ktime_get,
.resolution = KTIME_LOW_RES,
},
+ {
+ .index = CLOCK_BOOTTIME,
+ .get_time = &ktime_get_boottime,
+ .resolution = KTIME_LOW_RES,
+ },
}
};
@@ -90,16 +95,17 @@
*/
static void hrtimer_get_softirq_time(struct hrtimer_cpu_base *base)
{
- ktime_t xtim, tomono;
+ ktime_t xtim, mono, boot;
struct timespec xts, tom, slp;
get_xtime_and_monotonic_and_sleep_offset(&xts, &tom, &slp);
xtim = timespec_to_ktime(xts);
- tomono = timespec_to_ktime(tom);
+ mono = ktime_add(xtim, timespec_to_ktime(tom));
+ boot = ktime_add(mono, timespec_to_ktime(slp));
base->clock_base[HRTIMER_BASE_REALTIME].softirq_time = xtim;
- base->clock_base[HRTIMER_BASE_MONOTONIC].softirq_time =
- ktime_add(xtim, tomono);
+ base->clock_base[HRTIMER_BASE_MONOTONIC].softirq_time = mono;
+ base->clock_base[HRTIMER_BASE_BOOTTIME].softirq_time = boot;
}
/*
@@ -727,6 +733,7 @@
base->hres_active = 1;
base->clock_base[HRTIMER_BASE_REALTIME].resolution = KTIME_HIGH_RES;
base->clock_base[HRTIMER_BASE_MONOTONIC].resolution = KTIME_HIGH_RES;
+ base->clock_base[HRTIMER_BASE_BOOTTIME].resolution = KTIME_HIGH_RES;
tick_setup_sched_timer();
@@ -1719,6 +1726,7 @@
{
hrtimer_clock_to_base_table[CLOCK_REALTIME] = HRTIMER_BASE_REALTIME;
hrtimer_clock_to_base_table[CLOCK_MONOTONIC] = HRTIMER_BASE_MONOTONIC;
+ hrtimer_clock_to_base_table[CLOCK_BOOTTIME] = HRTIMER_BASE_BOOTTIME;
hrtimer_cpu_notify(&hrtimers_nb, (unsigned long)CPU_UP_PREPARE,
(void *)(long)smp_processor_id());