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authorJohn Stultz <john.stultz@linaro.org>2011-02-15 10:45:16 -0800
committerJohn Stultz <john.stultz@linaro.org>2011-02-21 12:53:08 -0800
commit70a08cca1227dc31c784ec930099a4417a06e7d0 (patch)
treed813ae86435a3104b66d18ee746d0f3ecc73a14a
parent314ac37150011ebb398f522db528d2dbcc611189 (diff)
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>
-rw-r--r--include/linux/hrtimer.h1
-rw-r--r--include/linux/time.h1
-rw-r--r--kernel/hrtimer.c16
3 files changed, 14 insertions, 4 deletions
diff --git a/include/linux/hrtimer.h b/include/linux/hrtimer.h
index 7a9e7ee0f35c..6bc1804bfbfa 100644
--- a/include/linux/hrtimer.h
+++ b/include/linux/hrtimer.h
@@ -151,6 +151,7 @@ struct hrtimer_clock_base {
enum hrtimer_base_type {
HRTIMER_BASE_REALTIME,
HRTIMER_BASE_MONOTONIC,
+ HRTIMER_BASE_BOOTTIME,
HRTIMER_MAX_CLOCK_BASES,
};
diff --git a/include/linux/time.h b/include/linux/time.h
index 02d48fb30b41..454a26205787 100644
--- a/include/linux/time.h
+++ b/include/linux/time.h
@@ -293,6 +293,7 @@ struct itimerval {
#define CLOCK_MONOTONIC_RAW 4
#define CLOCK_REALTIME_COARSE 5
#define CLOCK_MONOTONIC_COARSE 6
+#define CLOCK_BOOTTIME 7
/*
* The IDs of various hardware clocks:
diff --git a/kernel/hrtimer.c b/kernel/hrtimer.c
index e8bf3ad99063..4c53af18734b 100644
--- a/kernel/hrtimer.c
+++ b/kernel/hrtimer.c
@@ -73,6 +73,11 @@ DEFINE_PER_CPU(struct hrtimer_cpu_base, hrtimer_bases) =
.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 inline int hrtimer_clockid_to_base(clockid_t clock_id)
*/
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 @@ static int hrtimer_switch_to_hres(void)
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 @@ void __init hrtimers_init(void)
{
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());