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authorAndrew Dodd <atd7@cornell.edu>2013-02-16 18:41:04 -0500
committerAndrew Dodd <atd7@cornell.edu>2013-02-27 09:19:08 -0500
commitb08797f2afdfc604c3143f8725d058aeef8ddcb2 (patch)
treec59e963bd6931d4e9f9526034ab402cc551f18ae /kernel/time
parentcbfae70f1dcaf3cc6e93061179dad80caa1597fe (diff)
parent54ea5b40f067cf098cac639973c6628c6944cfb2 (diff)
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Merge remote-tracking branch 'kernelorg/linux-3.0.y' into 3_0_64
Conflicts: arch/arm/Kconfig arch/arm/include/asm/hwcap.h arch/arm/kernel/smp.c arch/arm/plat-samsung/adc.c drivers/gpu/drm/i915/i915_reg.h drivers/gpu/drm/i915/intel_drv.h drivers/mmc/core/sd.c drivers/net/tun.c drivers/net/usb/usbnet.c drivers/regulator/max8997.c drivers/usb/core/hub.c drivers/usb/host/xhci.h drivers/usb/serial/qcserial.c fs/jbd2/transaction.c include/linux/migrate.h kernel/sys.c kernel/time/timekeeping.c lib/genalloc.c mm/memory-failure.c mm/memory_hotplug.c mm/mempolicy.c mm/page_alloc.c mm/vmalloc.c mm/vmscan.c mm/vmstat.c scripts/Kbuild.include Change-Id: I91e2d85c07320c7ccfc04cf98a448e89bed6ade6
Diffstat (limited to 'kernel/time')
-rw-r--r--kernel/time/ntp.c128
-rw-r--r--kernel/time/timekeeping.c147
2 files changed, 161 insertions, 114 deletions
diff --git a/kernel/time/ntp.c b/kernel/time/ntp.c
index 4b85a7a..61fc450 100644
--- a/kernel/time/ntp.c
+++ b/kernel/time/ntp.c
@@ -31,8 +31,6 @@ unsigned long tick_nsec;
u64 tick_length;
static u64 tick_length_base;
-static struct hrtimer leap_timer;
-
#define MAX_TICKADJ 500LL /* usecs */
#define MAX_TICKADJ_SCALED \
(((MAX_TICKADJ * NSEC_PER_USEC) << NTP_SCALE_SHIFT) / NTP_INTERVAL_FREQ)
@@ -350,60 +348,64 @@ void ntp_clear(void)
}
/*
- * Leap second processing. If in leap-insert state at the end of the
- * day, the system clock is set back one second; if in leap-delete
- * state, the system clock is set ahead one second.
+ * this routine handles the overflow of the microsecond field
+ *
+ * The tricky bits of code to handle the accurate clock support
+ * were provided by Dave Mills (Mills@UDEL.EDU) of NTP fame.
+ * They were originally developed for SUN and DEC kernels.
+ * All the kudos should go to Dave for this stuff.
+ *
+ * Also handles leap second processing, and returns leap offset
*/
-static enum hrtimer_restart ntp_leap_second(struct hrtimer *timer)
+int second_overflow(unsigned long secs)
{
- enum hrtimer_restart res = HRTIMER_NORESTART;
-
- write_seqlock(&xtime_lock);
+ int leap = 0;
+ s64 delta;
+ /*
+ * Leap second processing. If in leap-insert state at the end of the
+ * day, the system clock is set back one second; if in leap-delete
+ * state, the system clock is set ahead one second.
+ */
switch (time_state) {
case TIME_OK:
+ if (time_status & STA_INS)
+ time_state = TIME_INS;
+ else if (time_status & STA_DEL)
+ time_state = TIME_DEL;
break;
case TIME_INS:
- timekeeping_leap_insert(-1);
- time_state = TIME_OOP;
- printk(KERN_NOTICE
- "Clock: inserting leap second 23:59:60 UTC\n");
- hrtimer_add_expires_ns(&leap_timer, NSEC_PER_SEC);
- res = HRTIMER_RESTART;
+ if (!(time_status & STA_INS))
+ time_state = TIME_OK;
+ else if (secs % 86400 == 0) {
+ leap = -1;
+ time_state = TIME_OOP;
+ time_tai++;
+ printk(KERN_NOTICE
+ "Clock: inserting leap second 23:59:60 UTC\n");
+ }
break;
case TIME_DEL:
- timekeeping_leap_insert(1);
- time_tai--;
- time_state = TIME_WAIT;
- printk(KERN_NOTICE
- "Clock: deleting leap second 23:59:59 UTC\n");
+ if (!(time_status & STA_DEL))
+ time_state = TIME_OK;
+ else if ((secs + 1) % 86400 == 0) {
+ leap = 1;
+ time_tai--;
+ time_state = TIME_WAIT;
+ printk(KERN_NOTICE
+ "Clock: deleting leap second 23:59:59 UTC\n");
+ }
break;
case TIME_OOP:
- time_tai++;
time_state = TIME_WAIT;
- /* fall through */
+ break;
+
case TIME_WAIT:
if (!(time_status & (STA_INS | STA_DEL)))
time_state = TIME_OK;
break;
}
- write_sequnlock(&xtime_lock);
-
- return res;
-}
-
-/*
- * this routine handles the overflow of the microsecond field
- *
- * The tricky bits of code to handle the accurate clock support
- * were provided by Dave Mills (Mills@UDEL.EDU) of NTP fame.
- * They were originally developed for SUN and DEC kernels.
- * All the kudos should go to Dave for this stuff.
- */
-void second_overflow(void)
-{
- s64 delta;
/* Bump the maxerror field */
time_maxerror += MAXFREQ / NSEC_PER_USEC;
@@ -423,23 +425,25 @@ void second_overflow(void)
pps_dec_valid();
if (!time_adjust)
- return;
+ goto out;
if (time_adjust > MAX_TICKADJ) {
time_adjust -= MAX_TICKADJ;
tick_length += MAX_TICKADJ_SCALED;
- return;
+ goto out;
}
if (time_adjust < -MAX_TICKADJ) {
time_adjust += MAX_TICKADJ;
tick_length -= MAX_TICKADJ_SCALED;
- return;
+ goto out;
}
tick_length += (s64)(time_adjust * NSEC_PER_USEC / NTP_INTERVAL_FREQ)
<< NTP_SCALE_SHIFT;
time_adjust = 0;
+out:
+ return leap;
}
#ifdef CONFIG_GENERIC_CMOS_UPDATE
@@ -501,27 +505,6 @@ static void notify_cmos_timer(void)
static inline void notify_cmos_timer(void) { }
#endif
-/*
- * Start the leap seconds timer:
- */
-static inline void ntp_start_leap_timer(struct timespec *ts)
-{
- long now = ts->tv_sec;
-
- if (time_status & STA_INS) {
- time_state = TIME_INS;
- now += 86400 - now % 86400;
- hrtimer_start(&leap_timer, ktime_set(now, 0), HRTIMER_MODE_ABS);
-
- return;
- }
-
- if (time_status & STA_DEL) {
- time_state = TIME_DEL;
- now += 86400 - (now + 1) % 86400;
- hrtimer_start(&leap_timer, ktime_set(now, 0), HRTIMER_MODE_ABS);
- }
-}
/*
* Propagate a new txc->status value into the NTP state:
@@ -546,22 +529,6 @@ static inline void process_adj_status(struct timex *txc, struct timespec *ts)
time_status &= STA_RONLY;
time_status |= txc->status & ~STA_RONLY;
- switch (time_state) {
- case TIME_OK:
- ntp_start_leap_timer(ts);
- break;
- case TIME_INS:
- case TIME_DEL:
- time_state = TIME_OK;
- ntp_start_leap_timer(ts);
- case TIME_WAIT:
- if (!(time_status & (STA_INS | STA_DEL)))
- time_state = TIME_OK;
- break;
- case TIME_OOP:
- hrtimer_restart(&leap_timer);
- break;
- }
}
/*
* Called with the xtime lock held, so we can access and modify
@@ -643,9 +610,6 @@ int do_adjtimex(struct timex *txc)
(txc->tick < 900000/USER_HZ ||
txc->tick > 1100000/USER_HZ))
return -EINVAL;
-
- if (txc->modes & ADJ_STATUS && time_state != TIME_OK)
- hrtimer_cancel(&leap_timer);
}
if (txc->modes & ADJ_SETOFFSET) {
@@ -967,6 +931,4 @@ __setup("ntp_tick_adj=", ntp_tick_adj_setup);
void __init ntp_init(void)
{
ntp_clear();
- hrtimer_init(&leap_timer, CLOCK_REALTIME, HRTIMER_MODE_ABS);
- leap_timer.function = ntp_leap_second;
}
diff --git a/kernel/time/timekeeping.c b/kernel/time/timekeeping.c
index c5406f9..e188977 100644
--- a/kernel/time/timekeeping.c
+++ b/kernel/time/timekeeping.c
@@ -167,23 +167,43 @@ static struct timespec xtime __attribute__ ((aligned (16)));
static struct timespec wall_to_monotonic __attribute__ ((aligned (16)));
static struct timespec total_sleep_time;
+/* Offset clock monotonic -> clock realtime */
+static ktime_t offs_real;
+
+/* Offset clock monotonic -> clock boottime */
+static ktime_t offs_boot;
+
/*
* The raw monotonic time for the CLOCK_MONOTONIC_RAW posix clock.
*/
static struct timespec raw_time;
-/* flag for if timekeeping is suspended */
-int __read_mostly timekeeping_suspended;
+/* must hold write on xtime_lock */
+static void update_rt_offset(void)
+{
+ struct timespec tmp, *wtm = &wall_to_monotonic;
+
+ set_normalized_timespec(&tmp, -wtm->tv_sec, -wtm->tv_nsec);
+ offs_real = timespec_to_ktime(tmp);
+}
-/* must hold xtime_lock */
-void timekeeping_leap_insert(int leapsecond)
+/* must hold write on xtime_lock */
+static void timekeeping_update(bool clearntp)
{
- xtime.tv_sec += leapsecond;
- wall_to_monotonic.tv_sec -= leapsecond;
- update_vsyscall(&xtime, &wall_to_monotonic, timekeeper.clock,
- timekeeper.mult);
+ if (clearntp) {
+ timekeeper.ntp_error = 0;
+ ntp_clear();
+ }
+ update_rt_offset();
+ update_vsyscall(&xtime, &wall_to_monotonic,
+ timekeeper.clock, timekeeper.mult);
}
+
+
+/* flag for if timekeeping is suspended */
+int __read_mostly timekeeping_suspended;
+
/**
* timekeeping_forward_now - update clock to the current time
*
@@ -368,7 +388,7 @@ int do_settimeofday(const struct timespec *tv)
struct timespec ts_delta;
unsigned long flags;
- if ((unsigned long)tv->tv_nsec >= NSEC_PER_SEC)
+ if (!timespec_valid_strict(tv))
return -EINVAL;
write_seqlock_irqsave(&xtime_lock, flags);
@@ -381,11 +401,7 @@ int do_settimeofday(const struct timespec *tv)
xtime = *tv;
- timekeeper.ntp_error = 0;
- ntp_clear();
-
- update_vsyscall(&xtime, &wall_to_monotonic, timekeeper.clock,
- timekeeper.mult);
+ timekeeping_update(true);
write_sequnlock_irqrestore(&xtime_lock, flags);
@@ -407,6 +423,8 @@ EXPORT_SYMBOL(do_settimeofday);
int timekeeping_inject_offset(struct timespec *ts)
{
unsigned long flags;
+ struct timespec tmp;
+ int ret = 0;
if ((unsigned long)ts->tv_nsec >= NSEC_PER_SEC)
return -EINVAL;
@@ -415,21 +433,24 @@ int timekeeping_inject_offset(struct timespec *ts)
timekeeping_forward_now();
+ tmp = timespec_add(xtime, *ts);
+ if (!timespec_valid_strict(&tmp)) {
+ ret = -EINVAL;
+ goto error;
+ }
+
xtime = timespec_add(xtime, *ts);
wall_to_monotonic = timespec_sub(wall_to_monotonic, *ts);
- timekeeper.ntp_error = 0;
- ntp_clear();
-
- update_vsyscall(&xtime, &wall_to_monotonic, timekeeper.clock,
- timekeeper.mult);
+error: /* even if we error out, we forwarded the time, so call update */
+ timekeeping_update(true);
write_sequnlock_irqrestore(&xtime_lock, flags);
/* signal hrtimers about time change */
clock_was_set();
- return 0;
+ return ret;
}
EXPORT_SYMBOL(timekeeping_inject_offset);
@@ -576,7 +597,20 @@ void __init timekeeping_init(void)
struct timespec now, boot;
read_persistent_clock(&now);
+ if (!timespec_valid_strict(&now)) {
+ pr_warn("WARNING: Persistent clock returned invalid value!\n"
+ " Check your CMOS/BIOS settings.\n");
+ now.tv_sec = 0;
+ now.tv_nsec = 0;
+ }
+
read_boot_clock(&boot);
+ if (!timespec_valid_strict(&boot)) {
+ pr_warn("WARNING: Boot clock returned invalid value!\n"
+ " Check your CMOS/BIOS settings.\n");
+ boot.tv_sec = 0;
+ boot.tv_nsec = 0;
+ }
write_seqlock_irqsave(&xtime_lock, flags);
@@ -597,6 +631,7 @@ void __init timekeeping_init(void)
}
set_normalized_timespec(&wall_to_monotonic,
-boot.tv_sec, -boot.tv_nsec);
+ update_rt_offset();
total_sleep_time.tv_sec = 0;
total_sleep_time.tv_nsec = 0;
write_sequnlock_irqrestore(&xtime_lock, flags);
@@ -605,6 +640,12 @@ void __init timekeeping_init(void)
/* time in seconds when suspend began */
static struct timespec timekeeping_suspend_time;
+static void update_sleep_time(struct timespec t)
+{
+ total_sleep_time = t;
+ offs_boot = timespec_to_ktime(t);
+}
+
/**
* __timekeeping_inject_sleeptime - Internal function to add sleep interval
* @delta: pointer to a timespec delta value
@@ -614,7 +655,7 @@ static struct timespec timekeeping_suspend_time;
*/
static void __timekeeping_inject_sleeptime(struct timespec *delta)
{
- if (!timespec_valid(delta)) {
+ if (!timespec_valid_strict(delta)) {
printk(KERN_WARNING "__timekeeping_inject_sleeptime: Invalid "
"sleep delta value!\n");
return;
@@ -622,7 +663,7 @@ static void __timekeeping_inject_sleeptime(struct timespec *delta)
xtime = timespec_add(xtime, *delta);
wall_to_monotonic = timespec_sub(wall_to_monotonic, *delta);
- total_sleep_time = timespec_add(total_sleep_time, *delta);
+ update_sleep_time(timespec_add(total_sleep_time, *delta));
}
@@ -651,10 +692,7 @@ void timekeeping_inject_sleeptime(struct timespec *delta)
__timekeeping_inject_sleeptime(delta);
- timekeeper.ntp_error = 0;
- ntp_clear();
- update_vsyscall(&xtime, &wall_to_monotonic, timekeeper.clock,
- timekeeper.mult);
+ timekeeping_update(true);
write_sequnlock_irqrestore(&xtime_lock, flags);
@@ -689,6 +727,7 @@ static void timekeeping_resume(void)
timekeeper.clock->cycle_last = timekeeper.clock->read(timekeeper.clock);
timekeeper.ntp_error = 0;
timekeeping_suspended = 0;
+ timekeeping_update(false);
write_sequnlock_irqrestore(&xtime_lock, flags);
touch_softlockup_watchdog();
@@ -840,9 +879,14 @@ static cycle_t logarithmic_accumulation(cycle_t offset, int shift)
timekeeper.xtime_nsec += timekeeper.xtime_interval << shift;
while (timekeeper.xtime_nsec >= nsecps) {
+ int leap;
timekeeper.xtime_nsec -= nsecps;
xtime.tv_sec++;
- second_overflow();
+ leap = second_overflow(xtime.tv_sec);
+ xtime.tv_sec += leap;
+ wall_to_monotonic.tv_sec -= leap;
+ if (leap)
+ clock_was_set_delayed();
}
/* Accumulate raw time */
@@ -887,6 +931,10 @@ static void update_wall_time(void)
#else
offset = (clock->read(clock) - clock->cycle_last) & clock->mask;
#endif
+ /* Check if there's really nothing to do */
+ if (offset < timekeeper.cycle_interval)
+ return;
+
timekeeper.xtime_nsec = (s64)xtime.tv_nsec << timekeeper.shift;
/*
@@ -948,14 +996,17 @@ static void update_wall_time(void)
* xtime.tv_nsec isn't larger then NSEC_PER_SEC
*/
if (unlikely(xtime.tv_nsec >= NSEC_PER_SEC)) {
+ int leap;
xtime.tv_nsec -= NSEC_PER_SEC;
xtime.tv_sec++;
- second_overflow();
+ leap = second_overflow(xtime.tv_sec);
+ xtime.tv_sec += leap;
+ wall_to_monotonic.tv_sec -= leap;
+ if (leap)
+ clock_was_set_delayed();
}
- /* check to see if there is a new clocksource to use */
- update_vsyscall(&xtime, &wall_to_monotonic, timekeeper.clock,
- timekeeper.mult);
+ timekeeping_update(false);
}
/**
@@ -1115,6 +1166,40 @@ void get_xtime_and_monotonic_and_sleep_offset(struct timespec *xtim,
} while (read_seqretry(&xtime_lock, seq));
}
+#ifdef CONFIG_HIGH_RES_TIMERS
+/**
+ * ktime_get_update_offsets - hrtimer helper
+ * @real: pointer to storage for monotonic -> realtime offset
+ * @_boot: pointer to storage for monotonic -> boottime offset
+ *
+ * Returns current monotonic time and updates the offsets
+ * Called from hrtimer_interupt() or retrigger_next_event()
+ */
+ktime_t ktime_get_update_offsets(ktime_t *real, ktime_t *boot)
+{
+ ktime_t now;
+ unsigned int seq;
+ u64 secs, nsecs;
+
+ do {
+ seq = read_seqbegin(&xtime_lock);
+
+ secs = xtime.tv_sec;
+ nsecs = xtime.tv_nsec;
+ nsecs += timekeeping_get_ns();
+ /* If arch requires, add in gettimeoffset() */
+ nsecs += arch_gettimeoffset();
+
+ *real = offs_real;
+ *boot = offs_boot;
+ } while (read_seqretry(&xtime_lock, seq));
+
+ now = ktime_add_ns(ktime_set(secs, 0), nsecs);
+ now = ktime_sub(now, *real);
+ return now;
+}
+#endif
+
/**
* ktime_get_monotonic_offset() - get wall_to_monotonic in ktime_t format
*/