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author | Thomas Gleixner <tglx@linutronix.de> | 2018-03-01 17:33:32 +0100 |
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committer | Ingo Molnar <mingo@kernel.org> | 2018-03-13 07:34:21 +0100 |
commit | 72199320d49dbafa1a99f94f1cd60dc90035c154 (patch) | |
tree | ca7a4e1337c8f56b404e4d7af0de73115fee88ce /kernel/time | |
parent | 78b98e3c5a66d569a53b8f57b6a698f912794a43 (diff) | |
download | linux-stable-72199320d49dbafa1a99f94f1cd60dc90035c154.tar.gz linux-stable-72199320d49dbafa1a99f94f1cd60dc90035c154.tar.bz2 linux-stable-72199320d49dbafa1a99f94f1cd60dc90035c154.zip |
timekeeping: Add the new CLOCK_MONOTONIC_ACTIVE clock
The planned change to unify the behaviour of the MONOTONIC and BOOTTIME
clocks vs. suspend removes the ability to retrieve the active
non-suspended time of a system.
Provide a new CLOCK_MONOTONIC_ACTIVE clock which returns the active
non-suspended time of the system via clock_gettime().
This preserves the old behaviour of CLOCK_MONOTONIC before the
BOOTTIME/MONOTONIC unification.
This new clock also allows applications to detect programmatically that
the MONOTONIC and BOOTTIME clocks are identical.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Cc: John Stultz <john.stultz@linaro.org>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Kevin Easton <kevin@guarana.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mark Salyzyn <salyzyn@android.com>
Cc: Michael Kerrisk <mtk.manpages@gmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Petr Mladek <pmladek@suse.com>
Cc: Prarit Bhargava <prarit@redhat.com>
Cc: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Link: http://lkml.kernel.org/r/20180301165149.965235774@linutronix.de
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Diffstat (limited to 'kernel/time')
-rw-r--r-- | kernel/time/posix-stubs.c | 2 | ||||
-rw-r--r-- | kernel/time/posix-timers.c | 13 | ||||
-rw-r--r-- | kernel/time/timekeeping.c | 36 |
3 files changed, 51 insertions, 0 deletions
diff --git a/kernel/time/posix-stubs.c b/kernel/time/posix-stubs.c index b258bee13b02..6259dbc0191a 100644 --- a/kernel/time/posix-stubs.c +++ b/kernel/time/posix-stubs.c @@ -73,6 +73,8 @@ int do_clock_gettime(clockid_t which_clock, struct timespec64 *tp) case CLOCK_BOOTTIME: get_monotonic_boottime64(tp); break; + case CLOCK_MONOTONIC_ACTIVE: + ktime_get_active_ts64(tp); default: return -EINVAL; } diff --git a/kernel/time/posix-timers.c b/kernel/time/posix-timers.c index 75043046914e..556fe02a47a4 100644 --- a/kernel/time/posix-timers.c +++ b/kernel/time/posix-timers.c @@ -263,6 +263,13 @@ static int posix_get_tai(clockid_t which_clock, struct timespec64 *tp) return 0; } +static int posix_get_monotonic_active(clockid_t which_clock, + struct timespec64 *tp) +{ + ktime_get_active_ts64(tp); + return 0; +} + static int posix_get_hrtimer_res(clockid_t which_clock, struct timespec64 *tp) { tp->tv_sec = 0; @@ -1330,6 +1337,11 @@ static const struct k_clock clock_boottime = { .timer_arm = common_hrtimer_arm, }; +static const struct k_clock clock_monotonic_active = { + .clock_getres = posix_get_hrtimer_res, + .clock_get = posix_get_monotonic_active, +}; + static const struct k_clock * const posix_clocks[] = { [CLOCK_REALTIME] = &clock_realtime, [CLOCK_MONOTONIC] = &clock_monotonic, @@ -1342,6 +1354,7 @@ static const struct k_clock * const posix_clocks[] = { [CLOCK_REALTIME_ALARM] = &alarm_clock, [CLOCK_BOOTTIME_ALARM] = &alarm_clock, [CLOCK_TAI] = &clock_tai, + [CLOCK_MONOTONIC_ACTIVE] = &clock_monotonic_active, }; static const struct k_clock *clockid_to_kclock(const clockid_t id) diff --git a/kernel/time/timekeeping.c b/kernel/time/timekeeping.c index e11760121cb2..a2b7f583e64e 100644 --- a/kernel/time/timekeeping.c +++ b/kernel/time/timekeeping.c @@ -139,6 +139,9 @@ static void tk_set_wall_to_mono(struct timekeeper *tk, struct timespec64 wtm) static inline void tk_update_sleep_time(struct timekeeper *tk, ktime_t delta) { tk->offs_boot = ktime_add(tk->offs_boot, delta); + + /* Accumulate time spent in suspend */ + tk->time_suspended += delta; } /* @@ -887,6 +890,39 @@ void ktime_get_ts64(struct timespec64 *ts) EXPORT_SYMBOL_GPL(ktime_get_ts64); /** + * ktime_get_active_ts64 - Get the active non-suspended monotonic clock + * @ts: pointer to timespec variable + * + * The function calculates the monotonic clock from the realtime clock and + * the wall_to_monotonic offset, subtracts the accumulated suspend time and + * stores the result in normalized timespec64 format in the variable + * pointed to by @ts. + */ +void ktime_get_active_ts64(struct timespec64 *ts) +{ + struct timekeeper *tk = &tk_core.timekeeper; + struct timespec64 tomono, tsusp; + u64 nsec, nssusp; + unsigned int seq; + + WARN_ON(timekeeping_suspended); + + do { + seq = read_seqcount_begin(&tk_core.seq); + ts->tv_sec = tk->xtime_sec; + nsec = timekeeping_get_ns(&tk->tkr_mono); + tomono = tk->wall_to_monotonic; + nssusp = tk->time_suspended; + } while (read_seqcount_retry(&tk_core.seq, seq)); + + ts->tv_sec += tomono.tv_sec; + ts->tv_nsec = 0; + timespec64_add_ns(ts, nsec + tomono.tv_nsec); + tsusp = ns_to_timespec64(nssusp); + *ts = timespec64_sub(*ts, tsusp); +} + +/** * ktime_get_seconds - Get the seconds portion of CLOCK_MONOTONIC * * Returns the seconds portion of CLOCK_MONOTONIC with a single non |