diff options
| -rw-r--r-- | kernel/time/timekeeping.c | 126 |
1 files changed, 82 insertions, 44 deletions
diff --git a/kernel/time/timekeeping.c b/kernel/time/timekeeping.c index 5df2e7e556ca..f5d4d226defb 100644 --- a/kernel/time/timekeeping.c +++ b/kernel/time/timekeeping.c @@ -69,6 +69,9 @@ struct timekeeper { struct timespec total_sleep_time; /* The raw monotonic time for the CLOCK_MONOTONIC_RAW posix clock. */ struct timespec raw_time; + + /* Seqlock for all timekeeper values */ + seqlock_t lock; }; static struct timekeeper timekeeper; @@ -172,10 +175,17 @@ static inline s64 timekeeping_get_ns_raw(void) /* must hold xtime_lock */ void timekeeping_leap_insert(int leapsecond) { + unsigned long flags; + + write_seqlock_irqsave(&timekeeper.lock, flags); + timekeeper.xtime.tv_sec += leapsecond; timekeeper.wall_to_monotonic.tv_sec -= leapsecond; update_vsyscall(&timekeeper.xtime, &timekeeper.wall_to_monotonic, timekeeper.clock, timekeeper.mult); + + write_sequnlock_irqrestore(&timekeeper.lock, flags); + } /** @@ -222,7 +232,7 @@ void getnstimeofday(struct timespec *ts) WARN_ON(timekeeping_suspended); do { - seq = read_seqbegin(&xtime_lock); + seq = read_seqbegin(&timekeeper.lock); *ts = timekeeper.xtime; nsecs = timekeeping_get_ns(); @@ -230,7 +240,7 @@ void getnstimeofday(struct timespec *ts) /* If arch requires, add in gettimeoffset() */ nsecs += arch_gettimeoffset(); - } while (read_seqretry(&xtime_lock, seq)); + } while (read_seqretry(&timekeeper.lock, seq)); timespec_add_ns(ts, nsecs); } @@ -245,7 +255,7 @@ ktime_t ktime_get(void) WARN_ON(timekeeping_suspended); do { - seq = read_seqbegin(&xtime_lock); + seq = read_seqbegin(&timekeeper.lock); secs = timekeeper.xtime.tv_sec + timekeeper.wall_to_monotonic.tv_sec; nsecs = timekeeper.xtime.tv_nsec + @@ -254,7 +264,7 @@ ktime_t ktime_get(void) /* If arch requires, add in gettimeoffset() */ nsecs += arch_gettimeoffset(); - } while (read_seqretry(&xtime_lock, seq)); + } while (read_seqretry(&timekeeper.lock, seq)); /* * Use ktime_set/ktime_add_ns to create a proper ktime on * 32-bit architectures without CONFIG_KTIME_SCALAR. @@ -280,14 +290,14 @@ void ktime_get_ts(struct timespec *ts) WARN_ON(timekeeping_suspended); do { - seq = read_seqbegin(&xtime_lock); + seq = read_seqbegin(&timekeeper.lock); *ts = timekeeper.xtime; tomono = timekeeper.wall_to_monotonic; nsecs = timekeeping_get_ns(); /* If arch requires, add in gettimeoffset() */ nsecs += arch_gettimeoffset(); - } while (read_seqretry(&xtime_lock, seq)); + } while (read_seqretry(&timekeeper.lock, seq)); set_normalized_timespec(ts, ts->tv_sec + tomono.tv_sec, ts->tv_nsec + tomono.tv_nsec + nsecs); @@ -315,7 +325,7 @@ void getnstime_raw_and_real(struct timespec *ts_raw, struct timespec *ts_real) do { u32 arch_offset; - seq = read_seqbegin(&xtime_lock); + seq = read_seqbegin(&timekeeper.lock); *ts_raw = timekeeper.raw_time; *ts_real = timekeeper.xtime; @@ -328,7 +338,7 @@ void getnstime_raw_and_real(struct timespec *ts_raw, struct timespec *ts_real) nsecs_raw += arch_offset; nsecs_real += arch_offset; - } while (read_seqretry(&xtime_lock, seq)); + } while (read_seqretry(&timekeeper.lock, seq)); timespec_add_ns(ts_raw, nsecs_raw); timespec_add_ns(ts_real, nsecs_real); @@ -362,12 +372,13 @@ EXPORT_SYMBOL(do_gettimeofday); int do_settimeofday(const struct timespec *tv) { struct timespec ts_delta; - unsigned long flags; + unsigned long flags1,flags2; if ((unsigned long)tv->tv_nsec >= NSEC_PER_SEC) return -EINVAL; - write_seqlock_irqsave(&xtime_lock, flags); + write_seqlock_irqsave(&xtime_lock, flags1); + write_seqlock_irqsave(&timekeeper.lock, flags2); timekeeping_forward_now(); @@ -384,7 +395,8 @@ int do_settimeofday(const struct timespec *tv) update_vsyscall(&timekeeper.xtime, &timekeeper.wall_to_monotonic, timekeeper.clock, timekeeper.mult); - write_sequnlock_irqrestore(&xtime_lock, flags); + write_sequnlock_irqrestore(&timekeeper.lock, flags2); + write_sequnlock_irqrestore(&xtime_lock, flags1); /* signal hrtimers about time change */ clock_was_set(); @@ -403,12 +415,13 @@ EXPORT_SYMBOL(do_settimeofday); */ int timekeeping_inject_offset(struct timespec *ts) { - unsigned long flags; + unsigned long flags1,flags2; if ((unsigned long)ts->tv_nsec >= NSEC_PER_SEC) return -EINVAL; - write_seqlock_irqsave(&xtime_lock, flags); + write_seqlock_irqsave(&xtime_lock, flags1); + write_seqlock_irqsave(&timekeeper.lock, flags2); timekeeping_forward_now(); @@ -422,7 +435,8 @@ int timekeeping_inject_offset(struct timespec *ts) update_vsyscall(&timekeeper.xtime, &timekeeper.wall_to_monotonic, timekeeper.clock, timekeeper.mult); - write_sequnlock_irqrestore(&xtime_lock, flags); + write_sequnlock_irqrestore(&timekeeper.lock, flags2); + write_sequnlock_irqrestore(&xtime_lock, flags1); /* signal hrtimers about time change */ clock_was_set(); @@ -494,11 +508,11 @@ void getrawmonotonic(struct timespec *ts) s64 nsecs; do { - seq = read_seqbegin(&xtime_lock); + seq = read_seqbegin(&timekeeper.lock); nsecs = timekeeping_get_ns_raw(); *ts = timekeeper.raw_time; - } while (read_seqretry(&xtime_lock, seq)); + } while (read_seqretry(&timekeeper.lock, seq)); timespec_add_ns(ts, nsecs); } @@ -514,24 +528,30 @@ int timekeeping_valid_for_hres(void) int ret; do { - seq = read_seqbegin(&xtime_lock); + seq = read_seqbegin(&timekeeper.lock); ret = timekeeper.clock->flags & CLOCK_SOURCE_VALID_FOR_HRES; - } while (read_seqretry(&xtime_lock, seq)); + } while (read_seqretry(&timekeeper.lock, seq)); return ret; } /** * timekeeping_max_deferment - Returns max time the clocksource can be deferred - * - * Caller must observe xtime_lock via read_seqbegin/read_seqretry to - * ensure that the clocksource does not change! */ u64 timekeeping_max_deferment(void) { - return timekeeper.clock->max_idle_ns; + unsigned long seq; + u64 ret; + do { + seq = read_seqbegin(&timekeeper.lock); + + ret = timekeeper.clock->max_idle_ns; + + } while (read_seqretry(&timekeeper.lock, seq)); + + return ret; } /** @@ -576,10 +596,13 @@ void __init timekeeping_init(void) read_persistent_clock(&now); read_boot_clock(&boot); - write_seqlock_irqsave(&xtime_lock, flags); + seqlock_init(&timekeeper.lock); + write_seqlock_irqsave(&xtime_lock, flags); ntp_init(); + write_sequnlock_irqrestore(&xtime_lock, flags); + write_seqlock_irqsave(&timekeeper.lock, flags); clock = clocksource_default_clock(); if (clock->enable) clock->enable(clock); @@ -597,7 +620,7 @@ void __init timekeeping_init(void) -boot.tv_sec, -boot.tv_nsec); timekeeper.total_sleep_time.tv_sec = 0; timekeeper.total_sleep_time.tv_nsec = 0; - write_sequnlock_irqrestore(&xtime_lock, flags); + write_sequnlock_irqrestore(&timekeeper.lock, flags); } /* time in seconds when suspend began */ @@ -638,7 +661,7 @@ static void __timekeeping_inject_sleeptime(struct timespec *delta) */ void timekeeping_inject_sleeptime(struct timespec *delta) { - unsigned long flags; + unsigned long flags1,flags2; struct timespec ts; /* Make sure we don't set the clock twice */ @@ -646,7 +669,9 @@ void timekeeping_inject_sleeptime(struct timespec *delta) if (!(ts.tv_sec == 0 && ts.tv_nsec == 0)) return; - write_seqlock_irqsave(&xtime_lock, flags); + write_seqlock_irqsave(&xtime_lock, flags1); + write_seqlock_irqsave(&timekeeper.lock, flags2); + timekeeping_forward_now(); __timekeeping_inject_sleeptime(delta); @@ -656,7 +681,8 @@ void timekeeping_inject_sleeptime(struct timespec *delta) update_vsyscall(&timekeeper.xtime, &timekeeper.wall_to_monotonic, timekeeper.clock, timekeeper.mult); - write_sequnlock_irqrestore(&xtime_lock, flags); + write_sequnlock_irqrestore(&timekeeper.lock, flags2); + write_sequnlock_irqrestore(&xtime_lock, flags1); /* signal hrtimers about time change */ clock_was_set(); @@ -672,14 +698,15 @@ void timekeeping_inject_sleeptime(struct timespec *delta) */ static void timekeeping_resume(void) { - unsigned long flags; + unsigned long flags1,flags2; struct timespec ts; read_persistent_clock(&ts); clocksource_resume(); - write_seqlock_irqsave(&xtime_lock, flags); + write_seqlock_irqsave(&xtime_lock, flags1); + write_seqlock_irqsave(&timekeeper.lock, flags2); if (timespec_compare(&ts, &timekeeping_suspend_time) > 0) { ts = timespec_sub(ts, timekeeping_suspend_time); @@ -689,7 +716,8 @@ static void timekeeping_resume(void) timekeeper.clock->cycle_last = timekeeper.clock->read(timekeeper.clock); timekeeper.ntp_error = 0; timekeeping_suspended = 0; - write_sequnlock_irqrestore(&xtime_lock, flags); + write_sequnlock_irqrestore(&timekeeper.lock, flags2); + write_sequnlock_irqrestore(&xtime_lock, flags1); touch_softlockup_watchdog(); @@ -701,13 +729,14 @@ static void timekeeping_resume(void) static int timekeeping_suspend(void) { - unsigned long flags; + unsigned long flags1,flags2; struct timespec delta, delta_delta; static struct timespec old_delta; read_persistent_clock(&timekeeping_suspend_time); - write_seqlock_irqsave(&xtime_lock, flags); + write_seqlock_irqsave(&xtime_lock, flags1); + write_seqlock_irqsave(&timekeeper.lock, flags2); timekeeping_forward_now(); timekeeping_suspended = 1; @@ -730,7 +759,8 @@ static int timekeeping_suspend(void) timekeeping_suspend_time = timespec_add(timekeeping_suspend_time, delta_delta); } - write_sequnlock_irqrestore(&xtime_lock, flags); + write_sequnlock_irqrestore(&timekeeper.lock, flags2); + write_sequnlock_irqrestore(&xtime_lock, flags1); clockevents_notify(CLOCK_EVT_NOTIFY_SUSPEND, NULL); clocksource_suspend(); @@ -983,10 +1013,13 @@ static void update_wall_time(void) struct clocksource *clock; cycle_t offset; int shift = 0, maxshift; + unsigned long flags; + + write_seqlock_irqsave(&timekeeper.lock, flags); /* Make sure we're fully resumed: */ if (unlikely(timekeeping_suspended)) - return; + goto out; clock = timekeeper.clock; @@ -1067,6 +1100,10 @@ static void update_wall_time(void) /* check to see if there is a new clocksource to use */ update_vsyscall(&timekeeper.xtime, &timekeeper.wall_to_monotonic, timekeeper.clock, timekeeper.mult); + +out: + write_sequnlock_irqrestore(&timekeeper.lock, flags); + } /** @@ -1112,13 +1149,13 @@ void get_monotonic_boottime(struct timespec *ts) WARN_ON(timekeeping_suspended); do { - seq = read_seqbegin(&xtime_lock); + seq = read_seqbegin(&timekeeper.lock); *ts = timekeeper.xtime; tomono = timekeeper.wall_to_monotonic; sleep = timekeeper.total_sleep_time; nsecs = timekeeping_get_ns(); - } while (read_seqretry(&xtime_lock, seq)); + } while (read_seqretry(&timekeeper.lock, seq)); set_normalized_timespec(ts, ts->tv_sec + tomono.tv_sec + sleep.tv_sec, ts->tv_nsec + tomono.tv_nsec + sleep.tv_nsec + nsecs); @@ -1169,10 +1206,10 @@ struct timespec current_kernel_time(void) unsigned long seq; do { - seq = read_seqbegin(&xtime_lock); + seq = read_seqbegin(&timekeeper.lock); now = timekeeper.xtime; - } while (read_seqretry(&xtime_lock, seq)); + } while (read_seqretry(&timekeeper.lock, seq)); return now; } @@ -1184,11 +1221,11 @@ struct timespec get_monotonic_coarse(void) unsigned long seq; do { - seq = read_seqbegin(&xtime_lock); + seq = read_seqbegin(&timekeeper.lock); now = timekeeper.xtime; mono = timekeeper.wall_to_monotonic; - } while (read_seqretry(&xtime_lock, seq)); + } while (read_seqretry(&timekeeper.lock, seq)); set_normalized_timespec(&now, now.tv_sec + mono.tv_sec, now.tv_nsec + mono.tv_nsec); @@ -1220,11 +1257,11 @@ void get_xtime_and_monotonic_and_sleep_offset(struct timespec *xtim, unsigned long seq; do { - seq = read_seqbegin(&xtime_lock); + seq = read_seqbegin(&timekeeper.lock); *xtim = timekeeper.xtime; *wtom = timekeeper.wall_to_monotonic; *sleep = timekeeper.total_sleep_time; - } while (read_seqretry(&xtime_lock, seq)); + } while (read_seqretry(&timekeeper.lock, seq)); } /** @@ -1236,9 +1273,10 @@ ktime_t ktime_get_monotonic_offset(void) struct timespec wtom; do { - seq = read_seqbegin(&xtime_lock); + seq = read_seqbegin(&timekeeper.lock); wtom = timekeeper.wall_to_monotonic; - } while (read_seqretry(&xtime_lock, seq)); + } while (read_seqretry(&timekeeper.lock, seq)); + return timespec_to_ktime(wtom); } |