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    Subject[patch 09/15] introduce struct timekeeper
    From: Martin Schwidefsky <schwidefsky@de.ibm.com>

    Add struct timekeeper to keep the internal values timekeeping.c needs
    in regard to the currently selected clock source. This moves the
    timekeeping intervals, xtime_nsec and the ntp error value from
    struct clocksource to struct timekeeper. The raw_time is removed from
    the clocksource as well. It gets treated like xtime as a global variable.
    Eventually xtime raw_time should be moved to struct timekeeper.

    Cc: Ingo Molnar <mingo@elte.hu>
    Cc: Thomas Gleixner <tglx@linutronix.de>
    Cc: john stultz <johnstul@us.ibm.com>
    Cc: Daniel Walker <dwalker@fifo99.com>
    Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
    ---
    arch/s390/kernel/time.c | 1
    include/linux/clocksource.h | 54 ----------
    kernel/time/clocksource.c | 6 -
    kernel/time/timekeeping.c | 233 +++++++++++++++++++++++++++++---------------
    4 files changed, 162 insertions(+), 132 deletions(-)

    Index: linux-2.6/arch/s390/kernel/time.c
    ===================================================================
    --- linux-2.6.orig/arch/s390/kernel/time.c
    +++ linux-2.6/arch/s390/kernel/time.c
    @@ -280,7 +280,6 @@ void __init time_init(void)
    now = get_clock();
    tod_to_timeval(now - TOD_UNIX_EPOCH, &xtime);
    clocksource_tod.cycle_last = now;
    - clocksource_tod.raw_time = xtime;
    tod_to_timeval(sched_clock_base_cc - TOD_UNIX_EPOCH, &ts);
    set_normalized_timespec(&wall_to_monotonic, -ts.tv_sec, -ts.tv_nsec);
    write_sequnlock_irqrestore(&xtime_lock, flags);
    Index: linux-2.6/include/linux/clocksource.h
    ===================================================================
    --- linux-2.6.orig/include/linux/clocksource.h
    +++ linux-2.6/include/linux/clocksource.h
    @@ -155,8 +155,6 @@ extern u64 timecounter_cyc2time(struct t
    * @flags: flags describing special properties
    * @vread: vsyscall based read
    * @resume: resume function for the clocksource, if necessary
    - * @cycle_interval: Used internally by timekeeping core, please ignore.
    - * @xtime_interval: Used internally by timekeeping core, please ignore.
    */
    struct clocksource {
    /*
    @@ -182,19 +180,12 @@ struct clocksource {
    #define CLKSRC_FSYS_MMIO_SET(mmio, addr) do { } while (0)
    #endif

    - /* timekeeping specific data, ignore */
    - cycle_t cycle_interval;
    - u64 xtime_interval;
    - u32 raw_interval;
    /*
    * Second part is written at each timer interrupt
    * Keep it in a different cache line to dirty no
    * more than one cache line.
    */
    cycle_t cycle_last ____cacheline_aligned_in_smp;
    - u64 xtime_nsec;
    - s64 error;
    - struct timespec raw_time;

    #ifdef CONFIG_CLOCKSOURCE_WATCHDOG
    /* Watchdog related data, used by the framework */
    @@ -203,8 +194,6 @@ struct clocksource {
    #endif
    };

    -extern struct clocksource *clock; /* current clocksource */
    -
    /*
    * Clock source flags bits::
    */
    @@ -270,50 +259,15 @@ static inline u32 clocksource_hz2mult(u3
    }

    /**
    - * cyc2ns - converts clocksource cycles to nanoseconds
    - * @cs: Pointer to clocksource
    - * @cycles: Cycles
    + * clocksource_cyc2ns - converts clocksource cycles to nanoseconds
    *
    - * Uses the clocksource and ntp ajdustment to convert cycle_ts to nanoseconds.
    + * Converts cycles to nanoseconds, using the given mult and shift.
    *
    * XXX - This could use some mult_lxl_ll() asm optimization
    */
    -static inline s64 cyc2ns(struct clocksource *cs, cycle_t cycles)
    -{
    - u64 ret = (u64)cycles;
    - ret = (ret * cs->mult) >> cs->shift;
    - return ret;
    -}
    -
    -/**
    - * clocksource_calculate_interval - Calculates a clocksource interval struct
    - *
    - * @c: Pointer to clocksource.
    - * @length_nsec: Desired interval length in nanoseconds.
    - *
    - * Calculates a fixed cycle/nsec interval for a given clocksource/adjustment
    - * pair and interval request.
    - *
    - * Unless you're the timekeeping code, you should not be using this!
    - */
    -static inline void clocksource_calculate_interval(struct clocksource *c,
    - unsigned long length_nsec)
    +static inline s64 clocksource_cyc2ns(cycle_t cycles, u32 mult, u32 shift)
    {
    - u64 tmp;
    -
    - /* Do the ns -> cycle conversion first, using original mult */
    - tmp = length_nsec;
    - tmp <<= c->shift;
    - tmp += c->mult_orig/2;
    - do_div(tmp, c->mult_orig);
    -
    - c->cycle_interval = (cycle_t)tmp;
    - if (c->cycle_interval == 0)
    - c->cycle_interval = 1;
    -
    - /* Go back from cycles -> shifted ns, this time use ntp adjused mult */
    - c->xtime_interval = (u64)c->cycle_interval * c->mult;
    - c->raw_interval = ((u64)c->cycle_interval * c->mult_orig) >> c->shift;
    + return ((u64) cycles * mult) >> shift;
    }


    Index: linux-2.6/kernel/time/clocksource.c
    ===================================================================
    --- linux-2.6.orig/kernel/time/clocksource.c
    +++ linux-2.6/kernel/time/clocksource.c
    @@ -177,7 +177,8 @@ static void clocksource_watchdog(unsigne
    goto out;

    wdnow = watchdog->read(watchdog);
    - wd_nsec = cyc2ns(watchdog, (wdnow - watchdog_last) & watchdog->mask);
    + wd_nsec = clocksource_cyc2ns((wdnow - watchdog_last) & watchdog->mask,
    + watchdog->mult, watchdog->shift);
    watchdog_last = wdnow;

    list_for_each_entry(cs, &watchdog_list, wd_list) {
    @@ -196,7 +197,8 @@ static void clocksource_watchdog(unsigne
    }

    /* Check the deviation from the watchdog clocksource. */
    - cs_nsec = cyc2ns(cs, (csnow - cs->wd_last) & cs->mask);
    + cs_nsec = clocksource_cyc2ns((csnow - cs->wd_last) &
    + cs->mask, cs->mult, cs->shift);
    cs->wd_last = csnow;
    if (abs(cs_nsec - wd_nsec) > WATCHDOG_THRESHOLD) {
    clocksource_unstable(cs, cs_nsec - wd_nsec);
    Index: linux-2.6/kernel/time/timekeeping.c
    ===================================================================
    --- linux-2.6.orig/kernel/time/timekeeping.c
    +++ linux-2.6/kernel/time/timekeeping.c
    @@ -19,6 +19,65 @@
    #include <linux/time.h>
    #include <linux/tick.h>

    +/* Structure holding internal timekeeping values. */
    +struct timekeeper {
    + /* Current clocksource used for timekeeping. */
    + struct clocksource *clock;
    +
    + /* Number of clock cycles in one NTP interval. */
    + cycle_t cycle_interval;
    + /* Number of clock shifted nano seconds in one NTP interval. */
    + u64 xtime_interval;
    + /* Raw nano seconds accumulated per NTP interval. */
    + u32 raw_interval;
    +
    + /* Clock shifted nano seconds remainder not stored in xtime.tv_nsec. */
    + u64 xtime_nsec;
    + /* Difference between accumulated time and NTP time in ntp
    + * shifted nano seconds. */
    + s64 ntp_error;
    +};
    +
    +struct timekeeper timekeeper;
    +
    +/**
    + * timekeeper_setup_internals - Set up internals to use clocksource clock.
    + *
    + * @clock: Pointer to clocksource.
    + *
    + * Calculates a fixed cycle/nsec interval for a given clocksource/adjustment
    + * pair and interval request.
    + *
    + * Unless you're the timekeeping code, you should not be using this!
    + */
    +static void timekeeper_setup_internals(struct clocksource *clock)
    +{
    + cycle_t interval;
    + u64 tmp;
    +
    + timekeeper.clock = clock;
    + clock->cycle_last = clock->read(clock);
    +
    + /* Do the ns -> cycle conversion first, using original mult */
    + tmp = NTP_INTERVAL_LENGTH;
    + tmp <<= clock->shift;
    + tmp += clock->mult_orig/2;
    + do_div(tmp, clock->mult_orig);
    + if (tmp == 0)
    + tmp = 1;
    +
    + interval = (cycle_t) tmp;
    + timekeeper.cycle_interval = interval;
    +
    + /* Go back from cycles -> shifted ns */
    + timekeeper.xtime_interval = (u64) interval * clock->mult;
    + timekeeper.raw_interval =
    + ((u64) interval * clock->mult_orig) >> clock->shift;
    +
    + timekeeper.xtime_nsec = 0;
    +
    + timekeeper.ntp_error = 0;
    +}

    /*
    * This read-write spinlock protects us from races in SMP while
    @@ -46,6 +105,11 @@ struct timespec xtime __attribute__ ((al
    struct timespec wall_to_monotonic __attribute__ ((aligned (16)));
    static unsigned long total_sleep_time; /* seconds */

    +/*
    + * The raw monotonic time for the CLOCK_MONOTONIC_RAW posix clock.
    + */
    +struct timespec raw_time;
    +
    /* flag for if timekeeping is suspended */
    int __read_mostly timekeeping_suspended;

    @@ -56,42 +120,42 @@ void update_xtime_cache(u64 nsec)
    timespec_add_ns(&xtime_cache, nsec);
    }

    -struct clocksource *clock;
    -
    /* must hold xtime_lock */
    void timekeeping_leap_insert(int leapsecond)
    {
    xtime.tv_sec += leapsecond;
    wall_to_monotonic.tv_sec -= leapsecond;
    - update_vsyscall(&xtime, clock);
    + update_vsyscall(&xtime, timekeeper.clock);
    }

    #ifdef CONFIG_GENERIC_TIME
    /**
    - * clocksource_forward_now - update clock to the current time
    + * timekeeping_forward_now - update clock to the current time
    *
    * Forward the current clock to update its state since the last call to
    * update_wall_time(). This is useful before significant clock changes,
    * as it avoids having to deal with this time offset explicitly.
    */
    -static void clocksource_forward_now(void)
    +static void timekeeping_forward_now(void)
    {
    cycle_t cycle_now, cycle_delta;
    + struct clocksource *clock;
    s64 nsec;

    + clock = timekeeper.clock;
    cycle_now = clock->read(clock);
    cycle_delta = (cycle_now - clock->cycle_last) & clock->mask;
    clock->cycle_last = cycle_now;

    - nsec = cyc2ns(clock, cycle_delta);
    + nsec = clocksource_cyc2ns(cycle_delta, clock->mult, clock->shift);

    /* If arch requires, add in gettimeoffset() */
    nsec += arch_gettimeoffset();

    timespec_add_ns(&xtime, nsec);

    - nsec = ((s64)cycle_delta * clock->mult_orig) >> clock->shift;
    - clock->raw_time.tv_nsec += nsec;
    + nsec = clocksource_cyc2ns(cycle_delta, clock->mult_orig, clock->shift);
    + timespec_add_ns(&raw_time, nsec);
    }

    /**
    @@ -103,6 +167,7 @@ static void clocksource_forward_now(void
    void getnstimeofday(struct timespec *ts)
    {
    cycle_t cycle_now, cycle_delta;
    + struct clocksource *clock;
    unsigned long seq;
    s64 nsecs;

    @@ -114,13 +179,15 @@ void getnstimeofday(struct timespec *ts)
    *ts = xtime;

    /* read clocksource: */
    + clock = timekeeper.clock;
    cycle_now = clock->read(clock);

    /* calculate the delta since the last update_wall_time: */
    cycle_delta = (cycle_now - clock->cycle_last) & clock->mask;

    /* convert to nanoseconds: */
    - nsecs = cyc2ns(clock, cycle_delta);
    + nsecs = clocksource_cyc2ns(cycle_delta, clock->mult,
    + clock->shift);

    /* If arch requires, add in gettimeoffset() */
    nsecs += arch_gettimeoffset();
    @@ -135,6 +202,7 @@ EXPORT_SYMBOL(getnstimeofday);
    ktime_t ktime_get(void)
    {
    cycle_t cycle_now, cycle_delta;
    + struct clocksource *clock;
    unsigned int seq;
    s64 secs, nsecs;

    @@ -146,13 +214,15 @@ ktime_t ktime_get(void)
    nsecs = xtime.tv_nsec + wall_to_monotonic.tv_nsec;

    /* read clocksource: */
    + clock = timekeeper.clock;
    cycle_now = clock->read(clock);

    /* calculate the delta since the last update_wall_time: */
    cycle_delta = (cycle_now - clock->cycle_last) & clock->mask;

    /* convert to nanoseconds: */
    - nsecs += cyc2ns(clock, cycle_delta);
    + nsecs += clocksource_cyc2ns(cycle_delta, clock->mult,
    + clock->shift);

    } while (read_seqretry(&xtime_lock, seq));
    /*
    @@ -174,6 +244,7 @@ EXPORT_SYMBOL_GPL(ktime_get);
    void ktime_get_ts(struct timespec *ts)
    {
    cycle_t cycle_now, cycle_delta;
    + struct clocksource *clock;
    struct timespec tomono;
    unsigned int seq;
    s64 nsecs;
    @@ -186,13 +257,15 @@ void ktime_get_ts(struct timespec *ts)
    tomono = wall_to_monotonic;

    /* read clocksource: */
    + clock = timekeeper.clock;
    cycle_now = clock->read(clock);

    /* calculate the delta since the last update_wall_time: */
    cycle_delta = (cycle_now - clock->cycle_last) & clock->mask;

    /* convert to nanoseconds: */
    - nsecs = cyc2ns(clock, cycle_delta);
    + nsecs = clocksource_cyc2ns(cycle_delta, clock->mult,
    + clock->shift);

    } while (read_seqretry(&xtime_lock, seq));

    @@ -233,7 +306,7 @@ int do_settimeofday(struct timespec *tv)

    write_seqlock_irqsave(&xtime_lock, flags);

    - clocksource_forward_now();
    + timekeeping_forward_now();

    ts_delta.tv_sec = tv->tv_sec - xtime.tv_sec;
    ts_delta.tv_nsec = tv->tv_nsec - xtime.tv_nsec;
    @@ -243,10 +316,10 @@ int do_settimeofday(struct timespec *tv)

    update_xtime_cache(0);

    - clock->error = 0;
    + timekeeper.ntp_error = 0;
    ntp_clear();

    - update_vsyscall(&xtime, clock);
    + update_vsyscall(&xtime, timekeeper.clock);

    write_sequnlock_irqrestore(&xtime_lock, flags);

    @@ -269,10 +342,10 @@ static void change_clocksource(void)

    new = clocksource_get_next();

    - if (!new || clock == new)
    + if (!new || timekeeper.clock == new)
    return;

    - clocksource_forward_now();
    + timekeeping_forward_now();

    if (new->enable && ! new->enable(new))
    return;
    @@ -284,9 +357,9 @@ static void change_clocksource(void)
    */
    new->mult_orig = new->mult;

    - new->raw_time = clock->raw_time;
    - old = clock;
    - clock = new;
    + old = timekeeper.clock;
    + timekeeper_setup_internals(new);
    +
    /*
    * Save mult_orig in mult so that the value can be restored
    * regardless if ->enable() updates the value of mult or not.
    @@ -295,22 +368,10 @@ static void change_clocksource(void)
    if (old->disable)
    old->disable(old);

    - clock->cycle_last = clock->read(clock);
    - clock->error = 0;
    - clock->xtime_nsec = 0;
    - clocksource_calculate_interval(clock, NTP_INTERVAL_LENGTH);
    -
    tick_clock_notify();
    -
    - /*
    - * We're holding xtime lock and waking up klogd would deadlock
    - * us on enqueue. So no printing!
    - printk(KERN_INFO "Time: %s clocksource has been installed.\n",
    - clock->name);
    - */
    }
    #else /* GENERIC_TIME */
    -static inline void clocksource_forward_now(void) { }
    +static inline void timekeeping_forward_now(void) { }
    static inline void change_clocksource(void) { }

    /**
    @@ -380,20 +441,23 @@ void getrawmonotonic(struct timespec *ts
    unsigned long seq;
    s64 nsecs;
    cycle_t cycle_now, cycle_delta;
    + struct clocksource *clock;

    do {
    seq = read_seqbegin(&xtime_lock);

    /* read clocksource: */
    + clock = timekeeper.clock;
    cycle_now = clock->read(clock);

    /* calculate the delta since the last update_wall_time: */
    cycle_delta = (cycle_now - clock->cycle_last) & clock->mask;

    /* convert to nanoseconds: */
    - nsecs = ((s64)cycle_delta * clock->mult_orig) >> clock->shift;
    + nsecs = clocksource_cyc2ns(cycle_delta, clock->mult_orig,
    + clock->shift);

    - *ts = clock->raw_time;
    + *ts = raw_time;

    } while (read_seqretry(&xtime_lock, seq));

    @@ -413,7 +477,7 @@ int timekeeping_valid_for_hres(void)
    do {
    seq = read_seqbegin(&xtime_lock);

    - ret = clock->flags & CLOCK_SOURCE_VALID_FOR_HRES;
    + ret = timekeeper.clock->flags & CLOCK_SOURCE_VALID_FOR_HRES;

    } while (read_seqretry(&xtime_lock, seq));

    @@ -439,6 +503,7 @@ unsigned long __attribute__((weak)) read
    */
    void __init timekeeping_init(void)
    {
    + struct clocksource *clock;
    unsigned long flags;
    unsigned long sec = read_persistent_clock();

    @@ -451,11 +516,13 @@ void __init timekeeping_init(void)
    clock->enable(clock);
    /* set mult_orig on enable */
    clock->mult_orig = clock->mult;
    - clocksource_calculate_interval(clock, NTP_INTERVAL_LENGTH);
    - clock->cycle_last = clock->read(clock);
    +
    + timekeeper_setup_internals(clock);

    xtime.tv_sec = sec;
    xtime.tv_nsec = 0;
    + raw_time.tv_sec = 0;
    + raw_time.tv_nsec = 0;
    set_normalized_timespec(&wall_to_monotonic,
    -xtime.tv_sec, -xtime.tv_nsec);
    update_xtime_cache(0);
    @@ -492,8 +559,8 @@ static int timekeeping_resume(struct sys
    }
    update_xtime_cache(0);
    /* re-base the last cycle value */
    - clock->cycle_last = clock->read(clock);
    - clock->error = 0;
    + timekeeper.clock->cycle_last = timekeeper.clock->read(timekeeper.clock);
    + timekeeper.ntp_error = 0;
    timekeeping_suspended = 0;
    write_sequnlock_irqrestore(&xtime_lock, flags);

    @@ -514,7 +581,7 @@ static int timekeeping_suspend(struct sy
    timekeeping_suspend_time = read_persistent_clock();

    write_seqlock_irqsave(&xtime_lock, flags);
    - clocksource_forward_now();
    + timekeeping_forward_now();
    timekeeping_suspended = 1;
    write_sequnlock_irqrestore(&xtime_lock, flags);

    @@ -549,7 +616,7 @@ device_initcall(timekeeping_init_device)
    * If the error is already larger, we look ahead even further
    * to compensate for late or lost adjustments.
    */
    -static __always_inline int clocksource_bigadjust(s64 error, s64 *interval,
    +static __always_inline int timekeeping_bigadjust(s64 error, s64 *interval,
    s64 *offset)
    {
    s64 tick_error, i;
    @@ -565,7 +632,7 @@ static __always_inline int clocksource_b
    * here. This is tuned so that an error of about 1 msec is adjusted
    * within about 1 sec (or 2^20 nsec in 2^SHIFT_HZ ticks).
    */
    - error2 = clock->error >> (NTP_SCALE_SHIFT + 22 - 2 * SHIFT_HZ);
    + error2 = timekeeper.ntp_error >> (NTP_SCALE_SHIFT + 22 - 2 * SHIFT_HZ);
    error2 = abs(error2);
    for (look_ahead = 0; error2 > 0; look_ahead++)
    error2 >>= 2;
    @@ -574,8 +641,9 @@ static __always_inline int clocksource_b
    * Now calculate the error in (1 << look_ahead) ticks, but first
    * remove the single look ahead already included in the error.
    */
    - tick_error = tick_length >> (NTP_SCALE_SHIFT - clock->shift + 1);
    - tick_error -= clock->xtime_interval >> 1;
    + tick_error = tick_length >>
    + (NTP_SCALE_SHIFT - timekeeper.clock->shift + 1);
    + tick_error -= timekeeper.xtime_interval >> 1;
    error = ((error - tick_error) >> look_ahead) + tick_error;

    /* Finally calculate the adjustment shift value. */
    @@ -600,18 +668,19 @@ static __always_inline int clocksource_b
    * this is optimized for the most common adjustments of -1,0,1,
    * for other values we can do a bit more work.
    */
    -static void clocksource_adjust(s64 offset)
    +static void timekeeping_adjust(s64 offset)
    {
    - s64 error, interval = clock->cycle_interval;
    + s64 error, interval = timekeeper.cycle_interval;
    int adj;

    - error = clock->error >> (NTP_SCALE_SHIFT - clock->shift - 1);
    + error = timekeeper.ntp_error >>
    + (NTP_SCALE_SHIFT - timekeeper.clock->shift - 1);
    if (error > interval) {
    error >>= 2;
    if (likely(error <= interval))
    adj = 1;
    else
    - adj = clocksource_bigadjust(error, &interval, &offset);
    + adj = timekeeping_bigadjust(error, &interval, &offset);
    } else if (error < -interval) {
    error >>= 2;
    if (likely(error >= -interval)) {
    @@ -619,15 +688,15 @@ static void clocksource_adjust(s64 offse
    interval = -interval;
    offset = -offset;
    } else
    - adj = clocksource_bigadjust(error, &interval, &offset);
    + adj = timekeeping_bigadjust(error, &interval, &offset);
    } else
    return;

    - clock->mult += adj;
    - clock->xtime_interval += interval;
    - clock->xtime_nsec -= offset;
    - clock->error -= (interval - offset) <<
    - (NTP_SCALE_SHIFT - clock->shift);
    + timekeeper.clock->mult += adj;
    + timekeeper.xtime_interval += interval;
    + timekeeper.xtime_nsec -= offset;
    + timekeeper.ntp_error -= (interval - offset) <<
    + (NTP_SCALE_SHIFT - timekeeper.clock->shift);
    }

    /**
    @@ -637,53 +706,57 @@ static void clocksource_adjust(s64 offse
    */
    void update_wall_time(void)
    {
    + struct clocksource *clock;
    cycle_t offset;
    + s64 nsecs;

    /* Make sure we're fully resumed: */
    if (unlikely(timekeeping_suspended))
    return;

    + clock = timekeeper.clock;
    #ifdef CONFIG_GENERIC_TIME
    offset = (clock->read(clock) - clock->cycle_last) & clock->mask;
    #else
    - offset = clock->cycle_interval;
    + offset = timekeeper.cycle_interval;
    #endif
    - clock->xtime_nsec = (s64)xtime.tv_nsec << clock->shift;
    + timekeeper.xtime_nsec = (s64)xtime.tv_nsec << clock->shift;

    /* normally this loop will run just once, however in the
    * case of lost or late ticks, it will accumulate correctly.
    */
    - while (offset >= clock->cycle_interval) {
    + while (offset >= timekeeper.cycle_interval) {
    /* accumulate one interval */
    - offset -= clock->cycle_interval;
    - clock->cycle_last += clock->cycle_interval;
    + offset -= timekeeper.cycle_interval;
    + clock->cycle_last += timekeeper.cycle_interval;

    - clock->xtime_nsec += clock->xtime_interval;
    - if (clock->xtime_nsec >= (u64)NSEC_PER_SEC << clock->shift) {
    - clock->xtime_nsec -= (u64)NSEC_PER_SEC << clock->shift;
    + timekeeper.xtime_nsec += timekeeper.xtime_interval;
    + if (timekeeper.xtime_nsec >= (u64)NSEC_PER_SEC << clock->shift) {
    + timekeeper.xtime_nsec -= (u64)NSEC_PER_SEC << clock->shift;
    xtime.tv_sec++;
    second_overflow();
    }

    - clock->raw_time.tv_nsec += clock->raw_interval;
    - if (clock->raw_time.tv_nsec >= NSEC_PER_SEC) {
    - clock->raw_time.tv_nsec -= NSEC_PER_SEC;
    - clock->raw_time.tv_sec++;
    + raw_time.tv_nsec += timekeeper.raw_interval;
    + if (raw_time.tv_nsec >= NSEC_PER_SEC) {
    + raw_time.tv_nsec -= NSEC_PER_SEC;
    + raw_time.tv_sec++;
    }

    /* accumulate error between NTP and clock interval */
    - clock->error += tick_length;
    - clock->error -= clock->xtime_interval << (NTP_SCALE_SHIFT - clock->shift);
    + timekeeper.ntp_error += tick_length;
    + timekeeper.ntp_error -= timekeeper.xtime_interval <<
    + (NTP_SCALE_SHIFT - clock->shift);
    }

    /* correct the clock when NTP error is too big */
    - clocksource_adjust(offset);
    + timekeeping_adjust(offset);

    /*
    * Since in the loop above, we accumulate any amount of time
    * in xtime_nsec over a second into xtime.tv_sec, its possible for
    * xtime_nsec to be fairly small after the loop. Further, if we're
    - * slightly speeding the clocksource up in clocksource_adjust(),
    + * slightly speeding the clocksource up in timekeeping_adjust(),
    * its possible the required corrective factor to xtime_nsec could
    * cause it to underflow.
    *
    @@ -695,24 +768,26 @@ void update_wall_time(void)
    * We'll correct this error next time through this function, when
    * xtime_nsec is not as small.
    */
    - if (unlikely((s64)clock->xtime_nsec < 0)) {
    - s64 neg = -(s64)clock->xtime_nsec;
    - clock->xtime_nsec = 0;
    - clock->error += neg << (NTP_SCALE_SHIFT - clock->shift);
    + if (unlikely((s64)timekeeper.xtime_nsec < 0)) {
    + s64 neg = -(s64)timekeeper.xtime_nsec;
    + timekeeper.xtime_nsec = 0;
    + timekeeper.ntp_error += neg << (NTP_SCALE_SHIFT - clock->shift);
    }

    /* store full nanoseconds into xtime after rounding it up and
    * add the remainder to the error difference.
    */
    - xtime.tv_nsec = ((s64)clock->xtime_nsec >> clock->shift) + 1;
    - clock->xtime_nsec -= (s64)xtime.tv_nsec << clock->shift;
    - clock->error += clock->xtime_nsec << (NTP_SCALE_SHIFT - clock->shift);
    + xtime.tv_nsec = ((s64)timekeeper.xtime_nsec >> clock->shift) + 1;
    + timekeeper.xtime_nsec -= (s64)xtime.tv_nsec << clock->shift;
    + timekeeper.ntp_error += timekeeper.xtime_nsec <<
    + (NTP_SCALE_SHIFT - clock->shift);

    - update_xtime_cache(cyc2ns(clock, offset));
    + nsecs = clocksource_cyc2ns(offset, clock->mult, clock->shift);
    + update_xtime_cache(nsecs);

    /* check to see if there is a new clocksource to use */
    change_clocksource();
    - update_vsyscall(&xtime, clock);
    + update_vsyscall(&xtime, timekeeper.clock);
    }

    /**
    --
    blue skies,
    Martin.

    "Reality continues to ruin my life." - Calvin.



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