Merge branch 'timers-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull timer fixes from Ingo Molnar:
 "One regression fix, and a couple of cleanups that clean up the code
  flow in areas that had high-profile bugs recently."

* 'timers-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  time: Remove all direct references to timekeeper
  time: Clean up offs_real/wall_to_mono and offs_boot/total_sleep_time updates
  time: Clean up stray newlines
  time/jiffies: Rename ACTHZ to SHIFTED_HZ
  time/jiffies: Allow CLOCK_TICK_RATE to be undefined
  time: Fix casting issue in tk_set_xtime and tk_xtime_add
This commit is contained in:
Linus Torvalds 2012-08-03 10:58:57 -07:00
commit ddc5057c1c
5 changed files with 226 additions and 183 deletions

View File

@ -39,9 +39,6 @@
# error Invalid value of HZ.
#endif
/* LATCH is used in the interval timer and ftape setup. */
#define LATCH ((CLOCK_TICK_RATE + HZ/2) / HZ) /* For divider */
/* Suppose we want to divide two numbers NOM and DEN: NOM/DEN, then we can
* improve accuracy by shifting LSH bits, hence calculating:
* (NOM << LSH) / DEN
@ -54,18 +51,30 @@
#define SH_DIV(NOM,DEN,LSH) ( (((NOM) / (DEN)) << (LSH)) \
+ ((((NOM) % (DEN)) << (LSH)) + (DEN) / 2) / (DEN))
/* HZ is the requested value. ACTHZ is actual HZ ("<< 8" is for accuracy) */
#define ACTHZ (SH_DIV (CLOCK_TICK_RATE, LATCH, 8))
#ifdef CLOCK_TICK_RATE
/* LATCH is used in the interval timer and ftape setup. */
# define LATCH ((CLOCK_TICK_RATE + HZ/2) / HZ) /* For divider */
/* TICK_NSEC is the time between ticks in nsec assuming real ACTHZ */
#define TICK_NSEC (SH_DIV (1000000UL * 1000, ACTHZ, 8))
/*
* HZ is the requested value. However the CLOCK_TICK_RATE may not allow
* for exactly HZ. So SHIFTED_HZ is high res HZ ("<< 8" is for accuracy)
*/
# define SHIFTED_HZ (SH_DIV(CLOCK_TICK_RATE, LATCH, 8))
#else
# define SHIFTED_HZ (HZ << 8)
#endif
/* TICK_NSEC is the time between ticks in nsec assuming SHIFTED_HZ */
#define TICK_NSEC (SH_DIV(1000000UL * 1000, SHIFTED_HZ, 8))
/* TICK_USEC is the time between ticks in usec assuming fake USER_HZ */
#define TICK_USEC ((1000000UL + USER_HZ/2) / USER_HZ)
/* TICK_USEC_TO_NSEC is the time between ticks in nsec assuming real ACTHZ and */
/* a value TUSEC for TICK_USEC (can be set bij adjtimex) */
#define TICK_USEC_TO_NSEC(TUSEC) (SH_DIV (TUSEC * USER_HZ * 1000, ACTHZ, 8))
/*
* TICK_USEC_TO_NSEC is the time between ticks in nsec assuming SHIFTED_HZ and
* a value TUSEC for TICK_USEC (can be set bij adjtimex)
*/
#define TICK_USEC_TO_NSEC(TUSEC) (SH_DIV(TUSEC * USER_HZ * 1000, SHIFTED_HZ, 8))
/* some arch's have a small-data section that can be accessed register-relative
* but that can only take up to, say, 4-byte variables. jiffies being part of

View File

@ -232,7 +232,7 @@ struct timex {
* estimated error = NTP dispersion.
*/
extern unsigned long tick_usec; /* USER_HZ period (usec) */
extern unsigned long tick_nsec; /* ACTHZ period (nsec) */
extern unsigned long tick_nsec; /* SHIFTED_HZ period (nsec) */
extern void ntp_init(void);
extern void ntp_clear(void);

View File

@ -37,7 +37,7 @@
* requested HZ value. It is also not recommended
* for "tick-less" systems.
*/
#define NSEC_PER_JIFFY ((u32)((((u64)NSEC_PER_SEC)<<8)/ACTHZ))
#define NSEC_PER_JIFFY ((u32)((((u64)NSEC_PER_SEC)<<8)/SHIFTED_HZ))
/* Since jiffies uses a simple NSEC_PER_JIFFY multiplier
* conversion, the .shift value could be zero. However

View File

@ -28,7 +28,7 @@ DEFINE_SPINLOCK(ntp_lock);
/* USER_HZ period (usecs): */
unsigned long tick_usec = TICK_USEC;
/* ACTHZ period (nsecs): */
/* SHIFTED_HZ period (nsecs): */
unsigned long tick_nsec;
static u64 tick_length;

View File

@ -65,14 +65,14 @@ struct timekeeper {
* used instead.
*/
struct timespec wall_to_monotonic;
/* time spent in suspend */
struct timespec total_sleep_time;
/* The raw monotonic time for the CLOCK_MONOTONIC_RAW posix clock. */
struct timespec raw_time;
/* Offset clock monotonic -> clock realtime */
ktime_t offs_real;
/* time spent in suspend */
struct timespec total_sleep_time;
/* Offset clock monotonic -> clock boottime */
ktime_t offs_boot;
/* The raw monotonic time for the CLOCK_MONOTONIC_RAW posix clock. */
struct timespec raw_time;
/* Seqlock for all timekeeper values */
seqlock_t lock;
};
@ -108,13 +108,38 @@ static struct timespec tk_xtime(struct timekeeper *tk)
static void tk_set_xtime(struct timekeeper *tk, const struct timespec *ts)
{
tk->xtime_sec = ts->tv_sec;
tk->xtime_nsec = ts->tv_nsec << tk->shift;
tk->xtime_nsec = (u64)ts->tv_nsec << tk->shift;
}
static void tk_xtime_add(struct timekeeper *tk, const struct timespec *ts)
{
tk->xtime_sec += ts->tv_sec;
tk->xtime_nsec += ts->tv_nsec << tk->shift;
tk->xtime_nsec += (u64)ts->tv_nsec << tk->shift;
}
static void tk_set_wall_to_mono(struct timekeeper *tk, struct timespec wtm)
{
struct timespec tmp;
/*
* Verify consistency of: offset_real = -wall_to_monotonic
* before modifying anything
*/
set_normalized_timespec(&tmp, -tk->wall_to_monotonic.tv_sec,
-tk->wall_to_monotonic.tv_nsec);
WARN_ON_ONCE(tk->offs_real.tv64 != timespec_to_ktime(tmp).tv64);
tk->wall_to_monotonic = wtm;
set_normalized_timespec(&tmp, -wtm.tv_sec, -wtm.tv_nsec);
tk->offs_real = timespec_to_ktime(tmp);
}
static void tk_set_sleep_time(struct timekeeper *tk, struct timespec t)
{
/* Verify consistency before modifying */
WARN_ON_ONCE(tk->offs_boot.tv64 != timespec_to_ktime(tk->total_sleep_time).tv64);
tk->total_sleep_time = t;
tk->offs_boot = timespec_to_ktime(t);
}
/**
@ -217,14 +242,6 @@ static inline s64 timekeeping_get_ns_raw(struct timekeeper *tk)
return nsec + arch_gettimeoffset();
}
static void update_rt_offset(struct timekeeper *tk)
{
struct timespec tmp, *wtm = &tk->wall_to_monotonic;
set_normalized_timespec(&tmp, -wtm->tv_sec, -wtm->tv_nsec);
tk->offs_real = timespec_to_ktime(tmp);
}
/* must hold write on timekeeper.lock */
static void timekeeping_update(struct timekeeper *tk, bool clearntp)
{
@ -234,12 +251,10 @@ static void timekeeping_update(struct timekeeper *tk, bool clearntp)
tk->ntp_error = 0;
ntp_clear();
}
update_rt_offset(tk);
xt = tk_xtime(tk);
update_vsyscall(&xt, &tk->wall_to_monotonic, tk->clock, tk->mult);
}
/**
* timekeeping_forward_now - update clock to the current time
*
@ -277,18 +292,19 @@ static void timekeeping_forward_now(struct timekeeper *tk)
*/
void getnstimeofday(struct timespec *ts)
{
struct timekeeper *tk = &timekeeper;
unsigned long seq;
s64 nsecs = 0;
WARN_ON(timekeeping_suspended);
do {
seq = read_seqbegin(&timekeeper.lock);
seq = read_seqbegin(&tk->lock);
ts->tv_sec = timekeeper.xtime_sec;
ts->tv_nsec = timekeeping_get_ns(&timekeeper);
ts->tv_sec = tk->xtime_sec;
ts->tv_nsec = timekeeping_get_ns(tk);
} while (read_seqretry(&timekeeper.lock, seq));
} while (read_seqretry(&tk->lock, seq));
timespec_add_ns(ts, nsecs);
}
@ -296,19 +312,18 @@ EXPORT_SYMBOL(getnstimeofday);
ktime_t ktime_get(void)
{
struct timekeeper *tk = &timekeeper;
unsigned int seq;
s64 secs, nsecs;
WARN_ON(timekeeping_suspended);
do {
seq = read_seqbegin(&timekeeper.lock);
secs = timekeeper.xtime_sec +
timekeeper.wall_to_monotonic.tv_sec;
nsecs = timekeeping_get_ns(&timekeeper) +
timekeeper.wall_to_monotonic.tv_nsec;
seq = read_seqbegin(&tk->lock);
secs = tk->xtime_sec + tk->wall_to_monotonic.tv_sec;
nsecs = timekeeping_get_ns(tk) + tk->wall_to_monotonic.tv_nsec;
} while (read_seqretry(&timekeeper.lock, seq));
} while (read_seqretry(&tk->lock, seq));
/*
* Use ktime_set/ktime_add_ns to create a proper ktime on
* 32-bit architectures without CONFIG_KTIME_SCALAR.
@ -327,18 +342,19 @@ EXPORT_SYMBOL_GPL(ktime_get);
*/
void ktime_get_ts(struct timespec *ts)
{
struct timekeeper *tk = &timekeeper;
struct timespec tomono;
unsigned int seq;
WARN_ON(timekeeping_suspended);
do {
seq = read_seqbegin(&timekeeper.lock);
ts->tv_sec = timekeeper.xtime_sec;
ts->tv_nsec = timekeeping_get_ns(&timekeeper);
tomono = timekeeper.wall_to_monotonic;
seq = read_seqbegin(&tk->lock);
ts->tv_sec = tk->xtime_sec;
ts->tv_nsec = timekeeping_get_ns(tk);
tomono = tk->wall_to_monotonic;
} while (read_seqretry(&timekeeper.lock, seq));
} while (read_seqretry(&tk->lock, seq));
set_normalized_timespec(ts, ts->tv_sec + tomono.tv_sec,
ts->tv_nsec + tomono.tv_nsec);
@ -358,22 +374,23 @@ EXPORT_SYMBOL_GPL(ktime_get_ts);
*/
void getnstime_raw_and_real(struct timespec *ts_raw, struct timespec *ts_real)
{
struct timekeeper *tk = &timekeeper;
unsigned long seq;
s64 nsecs_raw, nsecs_real;
WARN_ON_ONCE(timekeeping_suspended);
do {
seq = read_seqbegin(&timekeeper.lock);
seq = read_seqbegin(&tk->lock);
*ts_raw = timekeeper.raw_time;
ts_real->tv_sec = timekeeper.xtime_sec;
*ts_raw = tk->raw_time;
ts_real->tv_sec = tk->xtime_sec;
ts_real->tv_nsec = 0;
nsecs_raw = timekeeping_get_ns_raw(&timekeeper);
nsecs_real = timekeeping_get_ns(&timekeeper);
nsecs_raw = timekeeping_get_ns_raw(tk);
nsecs_real = timekeeping_get_ns(tk);
} while (read_seqretry(&timekeeper.lock, seq));
} while (read_seqretry(&tk->lock, seq));
timespec_add_ns(ts_raw, nsecs_raw);
timespec_add_ns(ts_real, nsecs_real);
@ -406,28 +423,28 @@ EXPORT_SYMBOL(do_gettimeofday);
*/
int do_settimeofday(const struct timespec *tv)
{
struct timekeeper *tk = &timekeeper;
struct timespec ts_delta, xt;
unsigned long flags;
if ((unsigned long)tv->tv_nsec >= NSEC_PER_SEC)
return -EINVAL;
write_seqlock_irqsave(&timekeeper.lock, flags);
write_seqlock_irqsave(&tk->lock, flags);
timekeeping_forward_now(&timekeeper);
timekeeping_forward_now(tk);
xt = tk_xtime(&timekeeper);
xt = tk_xtime(tk);
ts_delta.tv_sec = tv->tv_sec - xt.tv_sec;
ts_delta.tv_nsec = tv->tv_nsec - xt.tv_nsec;
timekeeper.wall_to_monotonic =
timespec_sub(timekeeper.wall_to_monotonic, ts_delta);
tk_set_wall_to_mono(tk, timespec_sub(tk->wall_to_monotonic, ts_delta));
tk_set_xtime(&timekeeper, tv);
tk_set_xtime(tk, tv);
timekeeping_update(&timekeeper, true);
timekeeping_update(tk, true);
write_sequnlock_irqrestore(&timekeeper.lock, flags);
write_sequnlock_irqrestore(&tk->lock, flags);
/* signal hrtimers about time change */
clock_was_set();
@ -436,7 +453,6 @@ int do_settimeofday(const struct timespec *tv)
}
EXPORT_SYMBOL(do_settimeofday);
/**
* timekeeping_inject_offset - Adds or subtracts from the current time.
* @tv: pointer to the timespec variable containing the offset
@ -445,23 +461,23 @@ EXPORT_SYMBOL(do_settimeofday);
*/
int timekeeping_inject_offset(struct timespec *ts)
{
struct timekeeper *tk = &timekeeper;
unsigned long flags;
if ((unsigned long)ts->tv_nsec >= NSEC_PER_SEC)
return -EINVAL;
write_seqlock_irqsave(&timekeeper.lock, flags);
write_seqlock_irqsave(&tk->lock, flags);
timekeeping_forward_now(&timekeeper);
timekeeping_forward_now(tk);
tk_xtime_add(&timekeeper, ts);
timekeeper.wall_to_monotonic =
timespec_sub(timekeeper.wall_to_monotonic, *ts);
tk_xtime_add(tk, ts);
tk_set_wall_to_mono(tk, timespec_sub(tk->wall_to_monotonic, *ts));
timekeeping_update(&timekeeper, true);
timekeeping_update(tk, true);
write_sequnlock_irqrestore(&timekeeper.lock, flags);
write_sequnlock_irqrestore(&tk->lock, flags);
/* signal hrtimers about time change */
clock_was_set();
@ -477,23 +493,24 @@ EXPORT_SYMBOL(timekeeping_inject_offset);
*/
static int change_clocksource(void *data)
{
struct timekeeper *tk = &timekeeper;
struct clocksource *new, *old;
unsigned long flags;
new = (struct clocksource *) data;
write_seqlock_irqsave(&timekeeper.lock, flags);
write_seqlock_irqsave(&tk->lock, flags);
timekeeping_forward_now(&timekeeper);
timekeeping_forward_now(tk);
if (!new->enable || new->enable(new) == 0) {
old = timekeeper.clock;
tk_setup_internals(&timekeeper, new);
old = tk->clock;
tk_setup_internals(tk, new);
if (old->disable)
old->disable(old);
}
timekeeping_update(&timekeeper, true);
timekeeping_update(tk, true);
write_sequnlock_irqrestore(&timekeeper.lock, flags);
write_sequnlock_irqrestore(&tk->lock, flags);
return 0;
}
@ -507,7 +524,9 @@ static int change_clocksource(void *data)
*/
void timekeeping_notify(struct clocksource *clock)
{
if (timekeeper.clock == clock)
struct timekeeper *tk = &timekeeper;
if (tk->clock == clock)
return;
stop_machine(change_clocksource, clock, NULL);
tick_clock_notify();
@ -536,35 +555,36 @@ EXPORT_SYMBOL_GPL(ktime_get_real);
*/
void getrawmonotonic(struct timespec *ts)
{
struct timekeeper *tk = &timekeeper;
unsigned long seq;
s64 nsecs;
do {
seq = read_seqbegin(&timekeeper.lock);
nsecs = timekeeping_get_ns_raw(&timekeeper);
*ts = timekeeper.raw_time;
seq = read_seqbegin(&tk->lock);
nsecs = timekeeping_get_ns_raw(tk);
*ts = tk->raw_time;
} while (read_seqretry(&timekeeper.lock, seq));
} while (read_seqretry(&tk->lock, seq));
timespec_add_ns(ts, nsecs);
}
EXPORT_SYMBOL(getrawmonotonic);
/**
* timekeeping_valid_for_hres - Check if timekeeping is suitable for hres
*/
int timekeeping_valid_for_hres(void)
{
struct timekeeper *tk = &timekeeper;
unsigned long seq;
int ret;
do {
seq = read_seqbegin(&timekeeper.lock);
seq = read_seqbegin(&tk->lock);
ret = timekeeper.clock->flags & CLOCK_SOURCE_VALID_FOR_HRES;
ret = tk->clock->flags & CLOCK_SOURCE_VALID_FOR_HRES;
} while (read_seqretry(&timekeeper.lock, seq));
} while (read_seqretry(&tk->lock, seq));
return ret;
}
@ -574,15 +594,16 @@ int timekeeping_valid_for_hres(void)
*/
u64 timekeeping_max_deferment(void)
{
struct timekeeper *tk = &timekeeper;
unsigned long seq;
u64 ret;
do {
seq = read_seqbegin(&timekeeper.lock);
seq = read_seqbegin(&tk->lock);
ret = timekeeper.clock->max_idle_ns;
ret = tk->clock->max_idle_ns;
} while (read_seqretry(&timekeeper.lock, seq));
} while (read_seqretry(&tk->lock, seq));
return ret;
}
@ -622,46 +643,43 @@ void __attribute__((weak)) read_boot_clock(struct timespec *ts)
*/
void __init timekeeping_init(void)
{
struct timekeeper *tk = &timekeeper;
struct clocksource *clock;
unsigned long flags;
struct timespec now, boot;
struct timespec now, boot, tmp;
read_persistent_clock(&now);
read_boot_clock(&boot);
seqlock_init(&timekeeper.lock);
seqlock_init(&tk->lock);
ntp_init();
write_seqlock_irqsave(&timekeeper.lock, flags);
write_seqlock_irqsave(&tk->lock, flags);
clock = clocksource_default_clock();
if (clock->enable)
clock->enable(clock);
tk_setup_internals(&timekeeper, clock);
tk_setup_internals(tk, clock);
tk_set_xtime(&timekeeper, &now);
timekeeper.raw_time.tv_sec = 0;
timekeeper.raw_time.tv_nsec = 0;
tk_set_xtime(tk, &now);
tk->raw_time.tv_sec = 0;
tk->raw_time.tv_nsec = 0;
if (boot.tv_sec == 0 && boot.tv_nsec == 0)
boot = tk_xtime(&timekeeper);
boot = tk_xtime(tk);
set_normalized_timespec(&timekeeper.wall_to_monotonic,
-boot.tv_sec, -boot.tv_nsec);
update_rt_offset(&timekeeper);
timekeeper.total_sleep_time.tv_sec = 0;
timekeeper.total_sleep_time.tv_nsec = 0;
write_sequnlock_irqrestore(&timekeeper.lock, flags);
set_normalized_timespec(&tmp, -boot.tv_sec, -boot.tv_nsec);
tk_set_wall_to_mono(tk, tmp);
tmp.tv_sec = 0;
tmp.tv_nsec = 0;
tk_set_sleep_time(tk, tmp);
write_sequnlock_irqrestore(&tk->lock, flags);
}
/* time in seconds when suspend began */
static struct timespec timekeeping_suspend_time;
static void update_sleep_time(struct timespec t)
{
timekeeper.total_sleep_time = t;
timekeeper.offs_boot = timespec_to_ktime(t);
}
/**
* __timekeeping_inject_sleeptime - Internal function to add sleep interval
* @delta: pointer to a timespec delta value
@ -677,13 +695,11 @@ static void __timekeeping_inject_sleeptime(struct timekeeper *tk,
"sleep delta value!\n");
return;
}
tk_xtime_add(tk, delta);
tk->wall_to_monotonic = timespec_sub(tk->wall_to_monotonic, *delta);
update_sleep_time(timespec_add(tk->total_sleep_time, *delta));
tk_set_wall_to_mono(tk, timespec_sub(tk->wall_to_monotonic, *delta));
tk_set_sleep_time(tk, timespec_add(tk->total_sleep_time, *delta));
}
/**
* timekeeping_inject_sleeptime - Adds suspend interval to timeekeeping values
* @delta: pointer to a timespec delta value
@ -696,6 +712,7 @@ static void __timekeeping_inject_sleeptime(struct timekeeper *tk,
*/
void timekeeping_inject_sleeptime(struct timespec *delta)
{
struct timekeeper *tk = &timekeeper;
unsigned long flags;
struct timespec ts;
@ -704,21 +721,20 @@ void timekeeping_inject_sleeptime(struct timespec *delta)
if (!(ts.tv_sec == 0 && ts.tv_nsec == 0))
return;
write_seqlock_irqsave(&timekeeper.lock, flags);
write_seqlock_irqsave(&tk->lock, flags);
timekeeping_forward_now(&timekeeper);
timekeeping_forward_now(tk);
__timekeeping_inject_sleeptime(&timekeeper, delta);
__timekeeping_inject_sleeptime(tk, delta);
timekeeping_update(&timekeeper, true);
timekeeping_update(tk, true);
write_sequnlock_irqrestore(&timekeeper.lock, flags);
write_sequnlock_irqrestore(&tk->lock, flags);
/* signal hrtimers about time change */
clock_was_set();
}
/**
* timekeeping_resume - Resumes the generic timekeeping subsystem.
*
@ -728,6 +744,7 @@ void timekeeping_inject_sleeptime(struct timespec *delta)
*/
static void timekeeping_resume(void)
{
struct timekeeper *tk = &timekeeper;
unsigned long flags;
struct timespec ts;
@ -735,18 +752,18 @@ static void timekeeping_resume(void)
clocksource_resume();
write_seqlock_irqsave(&timekeeper.lock, flags);
write_seqlock_irqsave(&tk->lock, flags);
if (timespec_compare(&ts, &timekeeping_suspend_time) > 0) {
ts = timespec_sub(ts, timekeeping_suspend_time);
__timekeeping_inject_sleeptime(&timekeeper, &ts);
__timekeeping_inject_sleeptime(tk, &ts);
}
/* re-base the last cycle value */
timekeeper.clock->cycle_last = timekeeper.clock->read(timekeeper.clock);
timekeeper.ntp_error = 0;
tk->clock->cycle_last = tk->clock->read(tk->clock);
tk->ntp_error = 0;
timekeeping_suspended = 0;
timekeeping_update(&timekeeper, false);
write_sequnlock_irqrestore(&timekeeper.lock, flags);
timekeeping_update(tk, false);
write_sequnlock_irqrestore(&tk->lock, flags);
touch_softlockup_watchdog();
@ -758,14 +775,15 @@ static void timekeeping_resume(void)
static int timekeeping_suspend(void)
{
struct timekeeper *tk = &timekeeper;
unsigned long flags;
struct timespec delta, delta_delta;
static struct timespec old_delta;
read_persistent_clock(&timekeeping_suspend_time);
write_seqlock_irqsave(&timekeeper.lock, flags);
timekeeping_forward_now(&timekeeper);
write_seqlock_irqsave(&tk->lock, flags);
timekeeping_forward_now(tk);
timekeeping_suspended = 1;
/*
@ -774,7 +792,7 @@ static int timekeeping_suspend(void)
* try to compensate so the difference in system time
* and persistent_clock time stays close to constant.
*/
delta = timespec_sub(tk_xtime(&timekeeper), timekeeping_suspend_time);
delta = timespec_sub(tk_xtime(tk), timekeeping_suspend_time);
delta_delta = timespec_sub(delta, old_delta);
if (abs(delta_delta.tv_sec) >= 2) {
/*
@ -787,7 +805,7 @@ static int timekeeping_suspend(void)
timekeeping_suspend_time =
timespec_add(timekeeping_suspend_time, delta_delta);
}
write_sequnlock_irqrestore(&timekeeper.lock, flags);
write_sequnlock_irqrestore(&tk->lock, flags);
clockevents_notify(CLOCK_EVT_NOTIFY_SUSPEND, NULL);
clocksource_suspend();
@ -898,7 +916,7 @@ static void timekeeping_adjust(struct timekeeper *tk, s64 offset)
* the error. This causes the likely below to be unlikely.
*
* The proper fix is to avoid rounding up by using
* the high precision timekeeper.xtime_nsec instead of
* the high precision tk->xtime_nsec instead of
* xtime.tv_nsec everywhere. Fixing this will take some
* time.
*/
@ -1003,7 +1021,6 @@ static void timekeeping_adjust(struct timekeeper *tk, s64 offset)
}
/**
* accumulate_nsecs_to_secs - Accumulates nsecs into secs
*
@ -1024,15 +1041,21 @@ static inline void accumulate_nsecs_to_secs(struct timekeeper *tk)
/* Figure out if its a leap sec and apply if needed */
leap = second_overflow(tk->xtime_sec);
tk->xtime_sec += leap;
tk->wall_to_monotonic.tv_sec -= leap;
if (leap)
clock_was_set_delayed();
if (unlikely(leap)) {
struct timespec ts;
tk->xtime_sec += leap;
ts.tv_sec = leap;
ts.tv_nsec = 0;
tk_set_wall_to_mono(tk,
timespec_sub(tk->wall_to_monotonic, ts));
clock_was_set_delayed();
}
}
}
/**
* logarithmic_accumulation - shifted accumulation of cycles
*
@ -1076,7 +1099,6 @@ static cycle_t logarithmic_accumulation(struct timekeeper *tk, cycle_t offset,
return offset;
}
/**
* update_wall_time - Uses the current clocksource to increment the wall time
*
@ -1084,21 +1106,22 @@ static cycle_t logarithmic_accumulation(struct timekeeper *tk, cycle_t offset,
static void update_wall_time(void)
{
struct clocksource *clock;
struct timekeeper *tk = &timekeeper;
cycle_t offset;
int shift = 0, maxshift;
unsigned long flags;
s64 remainder;
write_seqlock_irqsave(&timekeeper.lock, flags);
write_seqlock_irqsave(&tk->lock, flags);
/* Make sure we're fully resumed: */
if (unlikely(timekeeping_suspended))
goto out;
clock = timekeeper.clock;
clock = tk->clock;
#ifdef CONFIG_ARCH_USES_GETTIMEOFFSET
offset = timekeeper.cycle_interval;
offset = tk->cycle_interval;
#else
offset = (clock->read(clock) - clock->cycle_last) & clock->mask;
#endif
@ -1111,19 +1134,19 @@ static void update_wall_time(void)
* chunk in one go, and then try to consume the next smaller
* doubled multiple.
*/
shift = ilog2(offset) - ilog2(timekeeper.cycle_interval);
shift = ilog2(offset) - ilog2(tk->cycle_interval);
shift = max(0, shift);
/* Bound shift to one less than what overflows tick_length */
maxshift = (64 - (ilog2(ntp_tick_length())+1)) - 1;
shift = min(shift, maxshift);
while (offset >= timekeeper.cycle_interval) {
offset = logarithmic_accumulation(&timekeeper, offset, shift);
if(offset < timekeeper.cycle_interval<<shift)
while (offset >= tk->cycle_interval) {
offset = logarithmic_accumulation(tk, offset, shift);
if (offset < tk->cycle_interval<<shift)
shift--;
}
/* correct the clock when NTP error is too big */
timekeeping_adjust(&timekeeper, offset);
timekeeping_adjust(tk, offset);
/*
@ -1135,21 +1158,21 @@ static void update_wall_time(void)
* the vsyscall implementations are converted to use xtime_nsec
* (shifted nanoseconds), this can be killed.
*/
remainder = timekeeper.xtime_nsec & ((1 << timekeeper.shift) - 1);
timekeeper.xtime_nsec -= remainder;
timekeeper.xtime_nsec += 1 << timekeeper.shift;
timekeeper.ntp_error += remainder << timekeeper.ntp_error_shift;
remainder = tk->xtime_nsec & ((1 << tk->shift) - 1);
tk->xtime_nsec -= remainder;
tk->xtime_nsec += 1 << tk->shift;
tk->ntp_error += remainder << tk->ntp_error_shift;
/*
* Finally, make sure that after the rounding
* xtime_nsec isn't larger than NSEC_PER_SEC
*/
accumulate_nsecs_to_secs(&timekeeper);
accumulate_nsecs_to_secs(tk);
timekeeping_update(&timekeeper, false);
timekeeping_update(tk, false);
out:
write_sequnlock_irqrestore(&timekeeper.lock, flags);
write_sequnlock_irqrestore(&tk->lock, flags);
}
@ -1166,18 +1189,18 @@ out:
*/
void getboottime(struct timespec *ts)
{
struct timekeeper *tk = &timekeeper;
struct timespec boottime = {
.tv_sec = timekeeper.wall_to_monotonic.tv_sec +
timekeeper.total_sleep_time.tv_sec,
.tv_nsec = timekeeper.wall_to_monotonic.tv_nsec +
timekeeper.total_sleep_time.tv_nsec
.tv_sec = tk->wall_to_monotonic.tv_sec +
tk->total_sleep_time.tv_sec,
.tv_nsec = tk->wall_to_monotonic.tv_nsec +
tk->total_sleep_time.tv_nsec
};
set_normalized_timespec(ts, -boottime.tv_sec, -boottime.tv_nsec);
}
EXPORT_SYMBOL_GPL(getboottime);
/**
* get_monotonic_boottime - Returns monotonic time since boot
* @ts: pointer to the timespec to be set
@ -1189,19 +1212,20 @@ EXPORT_SYMBOL_GPL(getboottime);
*/
void get_monotonic_boottime(struct timespec *ts)
{
struct timekeeper *tk = &timekeeper;
struct timespec tomono, sleep;
unsigned int seq;
WARN_ON(timekeeping_suspended);
do {
seq = read_seqbegin(&timekeeper.lock);
ts->tv_sec = timekeeper.xtime_sec;
ts->tv_nsec = timekeeping_get_ns(&timekeeper);
tomono = timekeeper.wall_to_monotonic;
sleep = timekeeper.total_sleep_time;
seq = read_seqbegin(&tk->lock);
ts->tv_sec = tk->xtime_sec;
ts->tv_nsec = timekeeping_get_ns(tk);
tomono = tk->wall_to_monotonic;
sleep = tk->total_sleep_time;
} while (read_seqretry(&timekeeper.lock, seq));
} while (read_seqretry(&tk->lock, seq));
set_normalized_timespec(ts, ts->tv_sec + tomono.tv_sec + sleep.tv_sec,
ts->tv_nsec + tomono.tv_nsec + sleep.tv_nsec);
@ -1231,31 +1255,38 @@ EXPORT_SYMBOL_GPL(ktime_get_boottime);
*/
void monotonic_to_bootbased(struct timespec *ts)
{
*ts = timespec_add(*ts, timekeeper.total_sleep_time);
struct timekeeper *tk = &timekeeper;
*ts = timespec_add(*ts, tk->total_sleep_time);
}
EXPORT_SYMBOL_GPL(monotonic_to_bootbased);
unsigned long get_seconds(void)
{
return timekeeper.xtime_sec;
struct timekeeper *tk = &timekeeper;
return tk->xtime_sec;
}
EXPORT_SYMBOL(get_seconds);
struct timespec __current_kernel_time(void)
{
return tk_xtime(&timekeeper);
struct timekeeper *tk = &timekeeper;
return tk_xtime(tk);
}
struct timespec current_kernel_time(void)
{
struct timekeeper *tk = &timekeeper;
struct timespec now;
unsigned long seq;
do {
seq = read_seqbegin(&timekeeper.lock);
seq = read_seqbegin(&tk->lock);
now = tk_xtime(&timekeeper);
} while (read_seqretry(&timekeeper.lock, seq));
now = tk_xtime(tk);
} while (read_seqretry(&tk->lock, seq));
return now;
}
@ -1263,15 +1294,16 @@ EXPORT_SYMBOL(current_kernel_time);
struct timespec get_monotonic_coarse(void)
{
struct timekeeper *tk = &timekeeper;
struct timespec now, mono;
unsigned long seq;
do {
seq = read_seqbegin(&timekeeper.lock);
seq = read_seqbegin(&tk->lock);
now = tk_xtime(&timekeeper);
mono = timekeeper.wall_to_monotonic;
} while (read_seqretry(&timekeeper.lock, seq));
now = tk_xtime(tk);
mono = tk->wall_to_monotonic;
} while (read_seqretry(&tk->lock, seq));
set_normalized_timespec(&now, now.tv_sec + mono.tv_sec,
now.tv_nsec + mono.tv_nsec);
@ -1300,14 +1332,15 @@ void do_timer(unsigned long ticks)
void get_xtime_and_monotonic_and_sleep_offset(struct timespec *xtim,
struct timespec *wtom, struct timespec *sleep)
{
struct timekeeper *tk = &timekeeper;
unsigned long seq;
do {
seq = read_seqbegin(&timekeeper.lock);
*xtim = tk_xtime(&timekeeper);
*wtom = timekeeper.wall_to_monotonic;
*sleep = timekeeper.total_sleep_time;
} while (read_seqretry(&timekeeper.lock, seq));
seq = read_seqbegin(&tk->lock);
*xtim = tk_xtime(tk);
*wtom = tk->wall_to_monotonic;
*sleep = tk->total_sleep_time;
} while (read_seqretry(&tk->lock, seq));
}
#ifdef CONFIG_HIGH_RES_TIMERS
@ -1321,19 +1354,20 @@ void get_xtime_and_monotonic_and_sleep_offset(struct timespec *xtim,
*/
ktime_t ktime_get_update_offsets(ktime_t *offs_real, ktime_t *offs_boot)
{
struct timekeeper *tk = &timekeeper;
ktime_t now;
unsigned int seq;
u64 secs, nsecs;
do {
seq = read_seqbegin(&timekeeper.lock);
seq = read_seqbegin(&tk->lock);
secs = timekeeper.xtime_sec;
nsecs = timekeeping_get_ns(&timekeeper);
secs = tk->xtime_sec;
nsecs = timekeeping_get_ns(tk);
*offs_real = timekeeper.offs_real;
*offs_boot = timekeeper.offs_boot;
} while (read_seqretry(&timekeeper.lock, seq));
*offs_real = tk->offs_real;
*offs_boot = tk->offs_boot;
} while (read_seqretry(&tk->lock, seq));
now = ktime_add_ns(ktime_set(secs, 0), nsecs);
now = ktime_sub(now, *offs_real);
@ -1346,19 +1380,19 @@ ktime_t ktime_get_update_offsets(ktime_t *offs_real, ktime_t *offs_boot)
*/
ktime_t ktime_get_monotonic_offset(void)
{
struct timekeeper *tk = &timekeeper;
unsigned long seq;
struct timespec wtom;
do {
seq = read_seqbegin(&timekeeper.lock);
wtom = timekeeper.wall_to_monotonic;
} while (read_seqretry(&timekeeper.lock, seq));
seq = read_seqbegin(&tk->lock);
wtom = tk->wall_to_monotonic;
} while (read_seqretry(&tk->lock, seq));
return timespec_to_ktime(wtom);
}
EXPORT_SYMBOL_GPL(ktime_get_monotonic_offset);
/**
* xtime_update() - advances the timekeeping infrastructure
* @ticks: number of ticks, that have elapsed since the last call.