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authorMauro Carvalho Chehab <mchehab@redhat.com>2012-04-19 09:23:28 -0300
committerMauro Carvalho Chehab <mchehab@redhat.com>2012-04-19 09:23:28 -0300
commitd5aeee8cb28317ef608ecac421abc4d986d585d2 (patch)
tree70ec8ed8891f26e5c58152ffca9924ea1c58fe3a /kernel/time/ntp.c
parent32898a145404acbebe3256709e012c2830a2043b (diff)
parente816b57a337ea3b755de72bec38c10c864f23015 (diff)
Merge tag 'v3.4-rc3' into staging/for_v3.5
* tag 'v3.4-rc3': (3755 commits) Linux 3.4-rc3 x86-32: fix up strncpy_from_user() sign error ARM: 7386/1: jump_label: fixup for rename to static_key ARM: 7384/1: ThumbEE: Disable userspace TEEHBR access for !CONFIG_ARM_THUMBEE ARM: 7382/1: mm: truncate memory banks to fit in 4GB space for classic MMU ARM: 7359/2: smp_twd: Only wait for reprogramming on active cpus PCI: Fix regression in pci_restore_state(), v3 SCSI: Fix error handling when no ULD is attached ARM: OMAP: clock: cleanup CPUfreq leftovers, fix build errors ARM: dts: remove blank interrupt-parent properties ARM: EXYNOS: Fix Kconfig dependencies for device tree enabled machine files do not export kernel's NULL #define to userspace ARM: EXYNOS: Remove broken config values for touchscren for NURI board ARM: EXYNOS: set fix xusbxti clock for NURI and Universal210 boards ARM: EXYNOS: fix regulator name for NURI board ARM: SAMSUNG: make SAMSUNG_PM_DEBUG select DEBUG_LL cpufreq: OMAP: fix build errors: depends on ARCH_OMAP2PLUS sparc64: Eliminate obsolete __handle_softirq() function sparc64: Fix bootup crash on sun4v. ARM: msm: Fix section mismatches in proc_comm.c ...
Diffstat (limited to 'kernel/time/ntp.c')
-rw-r--r--kernel/time/ntp.c134
1 files changed, 42 insertions, 92 deletions
diff --git a/kernel/time/ntp.c b/kernel/time/ntp.c
index 6e039b144daf..f03fd83b170b 100644
--- a/kernel/time/ntp.c
+++ b/kernel/time/ntp.c
@@ -34,8 +34,6 @@ unsigned long tick_nsec;
static 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)
@@ -381,70 +379,63 @@ u64 ntp_tick_length(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;
- unsigned long flags;
+ s64 delta;
int leap = 0;
+ unsigned long flags;
spin_lock_irqsave(&ntp_lock, flags);
+
+ /*
+ * 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:
- leap = -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 (secs % 86400 == 0) {
+ leap = -1;
+ time_state = TIME_OOP;
+ printk(KERN_NOTICE
+ "Clock: inserting leap second 23:59:60 UTC\n");
+ }
break;
case TIME_DEL:
- leap = 1;
- time_tai--;
- time_state = TIME_WAIT;
- printk(KERN_NOTICE
- "Clock: deleting leap second 23:59:59 UTC\n");
+ 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;
}
- spin_unlock_irqrestore(&ntp_lock, flags);
- /*
- * We have to call this outside of the ntp_lock to keep
- * the proper locking hierarchy
- */
- if (leap)
- timekeeping_leap_insert(leap);
-
- 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;
- unsigned long flags;
-
- spin_lock_irqsave(&ntp_lock, flags);
/* Bump the maxerror field */
time_maxerror += MAXFREQ / NSEC_PER_USEC;
@@ -481,15 +472,17 @@ void second_overflow(void)
tick_length += (s64)(time_adjust * NSEC_PER_USEC / NTP_INTERVAL_FREQ)
<< NTP_SCALE_SHIFT;
time_adjust = 0;
+
+
+
out:
spin_unlock_irqrestore(&ntp_lock, flags);
+
+ return leap;
}
#ifdef CONFIG_GENERIC_CMOS_UPDATE
-/* Disable the cmos update - used by virtualization and embedded */
-int no_sync_cmos_clock __read_mostly;
-
static void sync_cmos_clock(struct work_struct *work);
static DECLARE_DELAYED_WORK(sync_cmos_work, sync_cmos_clock);
@@ -536,35 +529,13 @@ static void sync_cmos_clock(struct work_struct *work)
static void notify_cmos_timer(void)
{
- if (!no_sync_cmos_clock)
- schedule_delayed_work(&sync_cmos_work, 0);
+ schedule_delayed_work(&sync_cmos_work, 0);
}
#else
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:
@@ -589,22 +560,6 @@ 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
@@ -686,9 +641,6 @@ 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) {
@@ -1010,6 +962,4 @@ __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;
}