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ntp: rename TICK_LENGTH_SHIFT to NTP_SCALE_SHIFT
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As TICK_LENGTH_SHIFT is used for more than just the tick length, the name
isn't quite approriate anymore, so this renames it to NTP_SCALE_SHIFT.

Signed-off-by: Roman Zippel <zippel@linux-m68k.org>
Cc: john stultz <johnstul@us.ibm.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Roman Zippel authored and Linus Torvalds committed May 1, 2008
1 parent 153b5d0 commit 7fc5c78
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Showing 4 changed files with 20 additions and 20 deletions.
2 changes: 1 addition & 1 deletion arch/powerpc/kernel/time.c
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Original file line number Diff line number Diff line change
Expand Up @@ -149,7 +149,7 @@ EXPORT_SYMBOL(tb_ticks_per_sec); /* for cputime_t conversions */
u64 tb_to_xs;
unsigned tb_to_us;

#define TICKLEN_SCALE TICK_LENGTH_SHIFT
#define TICKLEN_SCALE NTP_SCALE_SHIFT
u64 last_tick_len; /* units are ns / 2^TICKLEN_SCALE */
u64 ticklen_to_xs; /* 0.64 fraction */

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8 changes: 4 additions & 4 deletions include/linux/timex.h
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Original file line number Diff line number Diff line change
Expand Up @@ -81,14 +81,14 @@
* offset and maximum frequency tolerance.
*/
#define SHIFT_USEC 16 /* frequency offset scale (shift) */
#define PPM_SCALE (NSEC_PER_USEC << (TICK_LENGTH_SHIFT - SHIFT_USEC))
#define PPM_SCALE (NSEC_PER_USEC << (NTP_SCALE_SHIFT - SHIFT_USEC))
#define PPM_SCALE_INV_SHIFT 20
#define PPM_SCALE_INV ((1ll << (PPM_SCALE_INV_SHIFT + TICK_LENGTH_SHIFT)) / \
#define PPM_SCALE_INV ((1ll << (PPM_SCALE_INV_SHIFT + NTP_SCALE_SHIFT)) / \
PPM_SCALE + 1)

#define MAXPHASE 500000000l /* max phase error (ns) */
#define MAXFREQ 500000 /* max frequency error (ns/s) */
#define MAXFREQ_SCALED ((s64)MAXFREQ << TICK_LENGTH_SHIFT)
#define MAXFREQ_SCALED ((s64)MAXFREQ << NTP_SCALE_SHIFT)
#define MINSEC 256 /* min interval between updates (s) */
#define MAXSEC 2048 /* max interval between updates (s) */
#define NTP_PHASE_LIMIT ((MAXPHASE / NSEC_PER_USEC) << 5) /* beyond max. dispersion */
Expand Down Expand Up @@ -230,7 +230,7 @@ static inline int ntp_synced(void)
__x < 0 ? -(-__x >> __s) : __x >> __s; \
})

#define TICK_LENGTH_SHIFT 32
#define NTP_SCALE_SHIFT 32

#ifdef CONFIG_NO_HZ
#define NTP_INTERVAL_FREQ (2)
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20 changes: 10 additions & 10 deletions kernel/time/ntp.c
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Original file line number Diff line number Diff line change
Expand Up @@ -27,7 +27,7 @@ static u64 tick_length, tick_length_base;

#define MAX_TICKADJ 500 /* microsecs */
#define MAX_TICKADJ_SCALED (((u64)(MAX_TICKADJ * NSEC_PER_USEC) << \
TICK_LENGTH_SHIFT) / NTP_INTERVAL_FREQ)
NTP_SCALE_SHIFT) / NTP_INTERVAL_FREQ)

/*
* phase-lock loop variables
Expand All @@ -48,13 +48,13 @@ static long ntp_tick_adj;
static void ntp_update_frequency(void)
{
u64 second_length = (u64)(tick_usec * NSEC_PER_USEC * USER_HZ)
<< TICK_LENGTH_SHIFT;
second_length += (s64)ntp_tick_adj << TICK_LENGTH_SHIFT;
<< NTP_SCALE_SHIFT;
second_length += (s64)ntp_tick_adj << NTP_SCALE_SHIFT;
second_length += time_freq;

tick_length_base = second_length;

tick_nsec = div_u64(second_length, HZ) >> TICK_LENGTH_SHIFT;
tick_nsec = div_u64(second_length, HZ) >> NTP_SCALE_SHIFT;
tick_length_base = div_u64(tick_length_base, NTP_INTERVAL_FREQ);
}

Expand Down Expand Up @@ -86,18 +86,18 @@ static void ntp_update_offset(long offset)
time_reftime = xtime.tv_sec;

freq_adj = (s64)offset * mtemp;
freq_adj <<= TICK_LENGTH_SHIFT - 2 * (SHIFT_PLL + 2 + time_constant);
freq_adj <<= NTP_SCALE_SHIFT - 2 * (SHIFT_PLL + 2 + time_constant);
time_status &= ~STA_MODE;
if (mtemp >= MINSEC && (time_status & STA_FLL || mtemp > MAXSEC)) {
freq_adj += div_s64((s64)offset << (TICK_LENGTH_SHIFT - SHIFT_FLL),
freq_adj += div_s64((s64)offset << (NTP_SCALE_SHIFT - SHIFT_FLL),
mtemp);
time_status |= STA_MODE;
}
freq_adj += time_freq;
freq_adj = min(freq_adj, MAXFREQ_SCALED);
time_freq = max(freq_adj, -MAXFREQ_SCALED);

time_offset = div_s64((s64)offset << TICK_LENGTH_SHIFT, NTP_INTERVAL_FREQ);
time_offset = div_s64((s64)offset << NTP_SCALE_SHIFT, NTP_INTERVAL_FREQ);
}

/**
Expand Down Expand Up @@ -197,7 +197,7 @@ void second_overflow(void)
tick_length -= MAX_TICKADJ_SCALED;
} else {
tick_length += (s64)(time_adjust * NSEC_PER_USEC /
NTP_INTERVAL_FREQ) << TICK_LENGTH_SHIFT;
NTP_INTERVAL_FREQ) << NTP_SCALE_SHIFT;
time_adjust = 0;
}
}
Expand Down Expand Up @@ -369,13 +369,13 @@ int do_adjtimex(struct timex *txc)
txc->offset = save_adjust;
else {
txc->offset = shift_right(time_offset * NTP_INTERVAL_FREQ,
TICK_LENGTH_SHIFT);
NTP_SCALE_SHIFT);
if (!(time_status & STA_NANO))
txc->offset /= NSEC_PER_USEC;
}
txc->freq = shift_right((s32)(time_freq >> PPM_SCALE_INV_SHIFT) *
(s64)PPM_SCALE_INV,
TICK_LENGTH_SHIFT);
NTP_SCALE_SHIFT);
txc->maxerror = time_maxerror;
txc->esterror = time_esterror;
txc->status = time_status;
Expand Down
10 changes: 5 additions & 5 deletions kernel/time/timekeeping.c
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Original file line number Diff line number Diff line change
Expand Up @@ -371,7 +371,7 @@ static __always_inline int clocksource_bigadjust(s64 error, s64 *interval,
* 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 >> (TICK_LENGTH_SHIFT + 22 - 2 * SHIFT_HZ);
error2 = clock->error >> (NTP_SCALE_SHIFT + 22 - 2 * SHIFT_HZ);
error2 = abs(error2);
for (look_ahead = 0; error2 > 0; look_ahead++)
error2 >>= 2;
Expand All @@ -381,7 +381,7 @@ static __always_inline int clocksource_bigadjust(s64 error, s64 *interval,
* remove the single look ahead already included in the error.
*/
tick_error = current_tick_length() >>
(TICK_LENGTH_SHIFT - clock->shift + 1);
(NTP_SCALE_SHIFT - clock->shift + 1);
tick_error -= clock->xtime_interval >> 1;
error = ((error - tick_error) >> look_ahead) + tick_error;

Expand Down Expand Up @@ -412,7 +412,7 @@ static void clocksource_adjust(s64 offset)
s64 error, interval = clock->cycle_interval;
int adj;

error = clock->error >> (TICK_LENGTH_SHIFT - clock->shift - 1);
error = clock->error >> (NTP_SCALE_SHIFT - clock->shift - 1);
if (error > interval) {
error >>= 2;
if (likely(error <= interval))
Expand All @@ -434,7 +434,7 @@ static void clocksource_adjust(s64 offset)
clock->xtime_interval += interval;
clock->xtime_nsec -= offset;
clock->error -= (interval - offset) <<
(TICK_LENGTH_SHIFT - clock->shift);
(NTP_SCALE_SHIFT - clock->shift);
}

/**
Expand Down Expand Up @@ -474,7 +474,7 @@ void update_wall_time(void)

/* accumulate error between NTP and clock interval */
clock->error += current_tick_length();
clock->error -= clock->xtime_interval << (TICK_LENGTH_SHIFT - clock->shift);
clock->error -= clock->xtime_interval << (NTP_SCALE_SHIFT - clock->shift);
}

/* correct the clock when NTP error is too big */
Expand Down

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