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time: Clean up CLOCK_MONOTONIC_RAW time handling

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Now that we fixed the sub-ns handling for CLOCK_MONOTONIC_RAW,
remove the duplicitive tk->raw_time.tv_nsec, which can be
stored in tk->tkr_raw.xtime_nsec (similarly to how its handled
for monotonic time).

Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Miroslav Lichvar <mlichvar@redhat.com>
Cc: Richard Cochran <richardcochran@gmail.com>
Cc: Prarit Bhargava <prarit@redhat.com>
Cc: Stephen Boyd <stephen.boyd@linaro.org>
Cc: Kevin Brodsky <kevin.brodsky@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Daniel Mentz <danielmentz@google.com>
Tested-by: Daniel Mentz <danielmentz@google.com>
Signed-off-by: John Stultz <john.stultz@linaro.org>
This commit is contained in:
John Stultz 2017-05-22 17:20:20 -07:00
parent 8e6cec1c7c
commit fc6eead7c1
3 changed files with 29 additions and 26 deletions
repo.diff.show_diff_stats Download patch file Download diff file Expand all files Collapse all files

6
arch/arm64/kernel/vdso.c
View file

@ -220,10 +220,8 @@ void update_vsyscall(struct timekeeper *tk)
if (!use_syscall) {
/* tkr_mono.cycle_last == tkr_raw.cycle_last */
vdso_data->cs_cycle_last = tk->tkr_mono.cycle_last;
vdso_data->raw_time_sec = tk->raw_time.tv_sec;
vdso_data->raw_time_nsec = (tk->raw_time.tv_nsec <<
tk->tkr_raw.shift) +
tk->tkr_raw.xtime_nsec;
vdso_data->raw_time_sec = tk->raw_sec;
vdso_data->raw_time_nsec = tk->tkr_raw.xtime_nsec;
vdso_data->xtime_clock_sec = tk->xtime_sec;
vdso_data->xtime_clock_nsec = tk->tkr_mono.xtime_nsec;
vdso_data->cs_mono_mult = tk->tkr_mono.mult;

4
include/linux/timekeeper_internal.h
View file

@ -51,7 +51,7 @@ struct tk_read_base {
* @clock_was_set_seq: The sequence number of clock was set events
* @cs_was_changed_seq: The sequence number of clocksource change events
* @next_leap_ktime: CLOCK_MONOTONIC time value of a pending leap-second
* @raw_time: Monotonic raw base time in timespec64 format
* @raw_sec: CLOCK_MONOTONIC_RAW time in seconds
* @cycle_interval: Number of clock cycles in one NTP interval
* @xtime_interval: Number of clock shifted nano seconds in one NTP
* interval.
@ -93,7 +93,7 @@ struct timekeeper {
unsigned int clock_was_set_seq;
u8 cs_was_changed_seq;
ktime_t next_leap_ktime;
struct timespec64 raw_time;
u64 raw_sec;
/* The following members are for timekeeping internal use */
u64 cycle_interval;

45
kernel/time/timekeeping.c
View file

@ -72,6 +72,10 @@ static inline void tk_normalize_xtime(struct timekeeper *tk)
tk->tkr_mono.xtime_nsec -= (u64)NSEC_PER_SEC << tk->tkr_mono.shift;
tk->xtime_sec++;
}
while (tk->tkr_raw.xtime_nsec >= ((u64)NSEC_PER_SEC << tk->tkr_raw.shift)) {
tk->tkr_raw.xtime_nsec -= (u64)NSEC_PER_SEC << tk->tkr_raw.shift;
tk->raw_sec++;
}
}
static inline struct timespec64 tk_xtime(struct timekeeper *tk)
@ -285,12 +289,14 @@ static void tk_setup_internals(struct timekeeper *tk, struct clocksource *clock)
/* if changing clocks, convert xtime_nsec shift units */
if (old_clock) {
int shift_change = clock->shift - old_clock->shift;
if (shift_change < 0)
if (shift_change < 0) {
tk->tkr_mono.xtime_nsec >>= -shift_change;
else
tk->tkr_raw.xtime_nsec >>= -shift_change;
} else {
tk->tkr_mono.xtime_nsec <<= shift_change;
tk->tkr_raw.xtime_nsec <<= shift_change;
}
}
tk->tkr_raw.xtime_nsec = 0;
tk->tkr_mono.shift = clock->shift;
tk->tkr_raw.shift = clock->shift;
@ -619,9 +625,6 @@ static inline void tk_update_ktime_data(struct timekeeper *tk)
nsec = (u32) tk->wall_to_monotonic.tv_nsec;
tk->tkr_mono.base = ns_to_ktime(seconds * NSEC_PER_SEC + nsec);
/* Update the monotonic raw base */
tk->tkr_raw.base = timespec64_to_ktime(tk->raw_time);
/*
* The sum of the nanoseconds portions of xtime and
* wall_to_monotonic can be greater/equal one second. Take
@ -631,6 +634,11 @@ static inline void tk_update_ktime_data(struct timekeeper *tk)
if (nsec >= NSEC_PER_SEC)
seconds++;
tk->ktime_sec = seconds;
/* Update the monotonic raw base */
seconds = tk->raw_sec;
nsec = (u32)(tk->tkr_raw.xtime_nsec >> tk->tkr_raw.shift);
tk->tkr_raw.base = ns_to_ktime(seconds * NSEC_PER_SEC + nsec);
}
/* must hold timekeeper_lock */
@ -672,7 +680,6 @@ static void timekeeping_update(struct timekeeper *tk, unsigned int action)
static void timekeeping_forward_now(struct timekeeper *tk)
{
u64 cycle_now, delta;
u64 nsec;
cycle_now = tk_clock_read(&tk->tkr_mono);
delta = clocksource_delta(cycle_now, tk->tkr_mono.cycle_last, tk->tkr_mono.mask);
@ -684,10 +691,13 @@ static void timekeeping_forward_now(struct timekeeper *tk)
/* If arch requires, add in get_arch_timeoffset() */
tk->tkr_mono.xtime_nsec += (u64)arch_gettimeoffset() << tk->tkr_mono.shift;
tk_normalize_xtime(tk);
nsec = clocksource_cyc2ns(delta, tk->tkr_raw.mult, tk->tkr_raw.shift);
timespec64_add_ns(&tk->raw_time, nsec);
tk->tkr_raw.xtime_nsec += delta * tk->tkr_raw.mult;
/* If arch requires, add in get_arch_timeoffset() */
tk->tkr_raw.xtime_nsec += (u64)arch_gettimeoffset() << tk->tkr_raw.shift;
tk_normalize_xtime(tk);
}
/**
@ -1373,19 +1383,18 @@ int timekeeping_notify(struct clocksource *clock)
void getrawmonotonic64(struct timespec64 *ts)
{
struct timekeeper *tk = &tk_core.timekeeper;
struct timespec64 ts64;
unsigned long seq;
u64 nsecs;
do {
seq = read_seqcount_begin(&tk_core.seq);
ts->tv_sec = tk->raw_sec;
nsecs = timekeeping_get_ns(&tk->tkr_raw);
ts64 = tk->raw_time;
} while (read_seqcount_retry(&tk_core.seq, seq));
timespec64_add_ns(&ts64, nsecs);
*ts = ts64;
ts->tv_nsec = 0;
timespec64_add_ns(ts, nsecs);
}
EXPORT_SYMBOL(getrawmonotonic64);
@ -1509,8 +1518,7 @@ void __init timekeeping_init(void)
tk_setup_internals(tk, clock);
tk_set_xtime(tk, &now);
tk->raw_time.tv_sec = 0;
tk->raw_time.tv_nsec = 0;
tk->raw_sec = 0;
if (boot.tv_sec == 0 && boot.tv_nsec == 0)
boot = tk_xtime(tk);
@ -2011,15 +2019,12 @@ static u64 logarithmic_accumulation(struct timekeeper *tk, u64 offset,
*clock_set |= accumulate_nsecs_to_secs(tk);
/* Accumulate raw time */
tk->tkr_raw.xtime_nsec += (u64)tk->raw_time.tv_nsec << tk->tkr_raw.shift;
tk->tkr_raw.xtime_nsec += tk->raw_interval << shift;
snsec_per_sec = (u64)NSEC_PER_SEC << tk->tkr_raw.shift;
while (tk->tkr_raw.xtime_nsec >= snsec_per_sec) {
tk->tkr_raw.xtime_nsec -= snsec_per_sec;
tk->raw_time.tv_sec++;
tk->raw_sec++;
}
tk->raw_time.tv_nsec = tk->tkr_raw.xtime_nsec >> tk->tkr_raw.shift;
tk->tkr_raw.xtime_nsec -= (u64)tk->raw_time.tv_nsec << tk->tkr_raw.shift;
/* Accumulate error between NTP and clock interval */
tk->ntp_error += tk->ntp_tick << shift;