[patch -mm 13/28] NTP: Move the cmos update code into ntp.c

Thomas Gleixner
2007-06-23T13:26:24Z

[-- Attachment #1: ntp-make-cmos-update-generic.patch --]
[-- Type: text/plain, Size: 9147 bytes --]

i386 and sparc64 have the identical code to update the cmos clock.
Move it into kernel/time/ntp.c as there are other architectures
coming along with the same requirements.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Chris Wright <chrisw@sous-sol.org>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: john stultz <johnstul@us.ibm.com>
Cc: David Miller <davem@davemloft.net>

---
arch/i386/Kconfig | 4 +++
arch/i386/kernel/time.c | 50 +-------------------------------------
arch/sparc64/Kconfig | 4 +++
arch/sparc64/kernel/time.c | 53 +---------------------------------------
include/asm-i386/timer.h | 1
include/linux/time.h | 2 +
kernel/time/ntp.c | 59 ++++++++++++++++++++++++++++++++++++++++++---
7 files changed, 70 insertions(+), 103 deletions(-)

Index: linux-2.6.22-rc4-mm/arch/i386/Kconfig
===================================================================
--- linux-2.6.22-rc4-mm.orig/arch/i386/Kconfig 2007-06-23 14:38:57.000000000 +0200
+++ linux-2.6.22-rc4-mm/arch/i386/Kconfig 2007-06-23 14:38:59.000000000 +0200
@@ -18,6 +18,10 @@ config GENERIC_TIME
bool
default y

+config GENERIC_CMOS_UPDATE
+ bool
+ default y
+
config CLOCKSOURCE_WATCHDOG
bool
default y
Index: linux-2.6.22-rc4-mm/arch/i386/kernel/time.c
===================================================================
--- linux-2.6.22-rc4-mm.orig/arch/i386/kernel/time.c 2007-06-23 14:38:55.000000000 +0200
+++ linux-2.6.22-rc4-mm/arch/i386/kernel/time.c 2007-06-23 14:38:59.000000000 +0200
@@ -207,55 +207,9 @@ unsigned long read_persistent_clock(void
return retval;
}

-static void sync_cmos_clock(unsigned long dummy);
-
-static DEFINE_TIMER(sync_cmos_timer, sync_cmos_clock, 0, 0);
-int no_sync_cmos_clock;
-
-static void sync_cmos_clock(unsigned long dummy)
-{
- struct timeval now, next;
- int fail = 1;
-
- /*
- * If we have an externally synchronized Linux clock, then update
- * CMOS clock accordingly every ~11 minutes. Set_rtc_mmss() has to be
- * called as close as possible to 500 ms before the new second starts.
- * This code is run on a timer. If the clock is set, that timer
- * may not expire at the correct time. Thus, we adjust...
- */
- if (!ntp_synced())
- /*
- * Not synced, exit, do not restart a timer (if one is
- * running, let it run out).
- */
- return;
-
- do_gettimeofday(&now);
- if (now.tv_usec >= USEC_AFTER - ((unsigned) TICK_SIZE) / 2 &&
- now.tv_usec <= USEC_BEFORE + ((unsigned) TICK_SIZE) / 2)
- fail = set_rtc_mmss(now.tv_sec);
-
- next.tv_usec = USEC_AFTER - now.tv_usec;
- if (next.tv_usec <= 0)
- next.tv_usec += USEC_PER_SEC;
-
- if (!fail)
- next.tv_sec = 659;
- else
- next.tv_sec = 0;
-
- if (next.tv_usec >= USEC_PER_SEC) {
- next.tv_sec++;
- next.tv_usec -= USEC_PER_SEC;
- }
- mod_timer(&sync_cmos_timer, jiffies + timeval_to_jiffies(&next));
-}
-
-void notify_arch_cmos_timer(void)
+int update_persistent_clock(struct timespec now)
{
- if (!no_sync_cmos_clock)
- mod_timer(&sync_cmos_timer, jiffies + 1);
+ return set_rtc_mmss(now.tv_sec);
}

extern void (*late_time_init)(void);
Index: linux-2.6.22-rc4-mm/arch/sparc64/kernel/time.c
===================================================================
--- linux-2.6.22-rc4-mm.orig/arch/sparc64/kernel/time.c 2007-06-23 14:38:58.000000000 +0200
+++ linux-2.6.22-rc4-mm/arch/sparc64/kernel/time.c 2007-06-23 14:38:59.000000000 +0200
@@ -403,58 +403,9 @@ static struct sparc64_tick_ops hbtick_op

static unsigned long timer_ticks_per_nsec_quotient __read_mostly;

-#define TICK_SIZE (tick_nsec / 1000)
-
-#define USEC_AFTER 500000
-#define USEC_BEFORE 500000
-
-static void sync_cmos_clock(unsigned long dummy);
-
-static DEFINE_TIMER(sync_cmos_timer, sync_cmos_clock, 0, 0);
-
-static void sync_cmos_clock(unsigned long dummy)
-{
- struct timeval now, next;
- int fail = 1;
-
- /*
- * If we have an externally synchronized Linux clock, then update
- * CMOS clock accordingly every ~11 minutes. Set_rtc_mmss() has to be
- * called as close as possible to 500 ms before the new second starts.
- * This code is run on a timer. If the clock is set, that timer
- * may not expire at the correct time. Thus, we adjust...
- */
- if (!ntp_synced())
- /*
- * Not synced, exit, do not restart a timer (if one is
- * running, let it run out).
- */
- return;
-
- do_gettimeofday(&now);
- if (now.tv_usec >= USEC_AFTER - ((unsigned) TICK_SIZE) / 2 &&
- now.tv_usec <= USEC_BEFORE + ((unsigned) TICK_SIZE) / 2)
- fail = set_rtc_mmss(now.tv_sec);
-
- next.tv_usec = USEC_AFTER - now.tv_usec;
- if (next.tv_usec <= 0)
- next.tv_usec += USEC_PER_SEC;
-
- if (!fail)
- next.tv_sec = 659;
- else
- next.tv_sec = 0;
-
- if (next.tv_usec >= USEC_PER_SEC) {
- next.tv_sec++;
- next.tv_usec -= USEC_PER_SEC;
- }
- mod_timer(&sync_cmos_timer, jiffies + timeval_to_jiffies(&next));
-}
-
-void notify_arch_cmos_timer(void)
+int update_persistent_clock(struct timespec now)
{
- mod_timer(&sync_cmos_timer, jiffies + 1);
+ return set_rtc_mmss(now.tv_sec);
}

/* Kick start a stopped clock (procedure from the Sun NVRAM/hostid FAQ). */
Index: linux-2.6.22-rc4-mm/include/linux/time.h
===================================================================
--- linux-2.6.22-rc4-mm.orig/include/linux/time.h 2007-06-23 14:38:55.000000000 +0200
+++ linux-2.6.22-rc4-mm/include/linux/time.h 2007-06-23 14:38:59.000000000 +0200
@@ -93,6 +93,8 @@ extern struct timespec wall_to_monotonic
extern seqlock_t xtime_lock __attribute__((weak));

extern unsigned long read_persistent_clock(void);
+extern int update_persistent_clock(struct timespec now);
+extern int no_sync_cmos_clock __read_mostly;
void timekeeping_init(void);

static inline unsigned long get_seconds(void)
Index: linux-2.6.22-rc4-mm/kernel/time/ntp.c
===================================================================
--- linux-2.6.22-rc4-mm.orig/kernel/time/ntp.c 2007-06-23 14:38:55.000000000 +0200
+++ linux-2.6.22-rc4-mm/kernel/time/ntp.c 2007-06-23 14:38:59.000000000 +0200
@@ -10,6 +10,7 @@

#include <linux/mm.h>
#include <linux/time.h>
+#include <linux/timer.h>
#include <linux/timex.h>
#include <linux/jiffies.h>
#include <linux/hrtimer.h>
@@ -187,12 +188,64 @@ u64 current_tick_length(void)
return tick_length;
}

+#ifdef CONFIG_GENERIC_CMOS_UPDATE

-void __attribute__ ((weak)) notify_arch_cmos_timer(void)
+/* Disable the cmos update - used by virtualization and embedded */
+int no_sync_cmos_clock __read_mostly;
+
+static void sync_cmos_clock(unsigned long dummy);
+
+static DEFINE_TIMER(sync_cmos_timer, sync_cmos_clock, 0, 0);
+
+static void sync_cmos_clock(unsigned long dummy)
{
- return;
+ struct timespec now, next;
+ int fail = 1;
+
+ /*
+ * If we have an externally synchronized Linux clock, then update
+ * CMOS clock accordingly every ~11 minutes. Set_rtc_mmss() has to be
+ * called as close as possible to 500 ms before the new second starts.
+ * This code is run on a timer. If the clock is set, that timer
+ * may not expire at the correct time. Thus, we adjust...
+ */
+ if (!ntp_synced())
+ /*
+ * Not synced, exit, do not restart a timer (if one is
+ * running, let it run out).
+ */
+ return;
+
+ getnstimeofday(&now);
+ if (abs(xtime.tv_nsec - (NSEC_PER_SEC / 2)) <= tick_nsec / 2)
+ fail = update_persistent_clock(now);
+
+ next.tv_nsec = (NSEC_PER_SEC / 2) - now.tv_nsec;
+ if (next.tv_nsec <= 0)
+ next.tv_nsec += NSEC_PER_SEC;
+
+ if (!fail)
+ next.tv_sec = 659;
+ else
+ next.tv_sec = 0;
+
+ if (next.tv_nsec >= NSEC_PER_SEC) {
+ next.tv_sec++;
+ next.tv_nsec -= NSEC_PER_SEC;
+ }
+ mod_timer(&sync_cmos_timer, jiffies + timespec_to_jiffies(&next));
}

+static void notify_cmos_timer(void)
+{
+ if (no_sync_cmos_clock)
+ mod_timer(&sync_cmos_timer, jiffies + 1);
+}
+
+#else
+static inline void notify_cmos_timer(void) { }
+#endif
+
/* adjtimex mainly allows reading (and writing, if superuser) of
* kernel time-keeping variables. used by xntpd.
*/
@@ -357,6 +410,6 @@ leave: if ((time_status & (STA_UNSYNC|ST
txc->stbcnt = 0;
write_sequnlock_irq(&xtime_lock);
do_gettimeofday(&txc->time);
- notify_arch_cmos_timer();
+ notify_cmos_timer();
return(result);
}
Index: linux-2.6.22-rc4-mm/arch/sparc64/Kconfig
===================================================================
--- linux-2.6.22-rc4-mm.orig/arch/sparc64/Kconfig 2007-06-23 14:38:55.000000000 +0200
+++ linux-2.6.22-rc4-mm/arch/sparc64/Kconfig 2007-06-23 14:38:59.000000000 +0200
@@ -23,6 +23,10 @@ config GENERIC_TIME
bool
default y

+config GENERIC_CMOS_UPDATE
+ bool
+ default y
+
config GENERIC_CLOCKEVENTS
bool
default y
Index: linux-2.6.22-rc4-mm/include/asm-i386/timer.h
===================================================================
--- linux-2.6.22-rc4-mm.orig/include/asm-i386/timer.h 2007-06-23 14:38:55.000000000 +0200
+++ linux-2.6.22-rc4-mm/include/asm-i386/timer.h 2007-06-23 14:38:59.000000000 +0200
@@ -12,7 +12,6 @@ unsigned long native_calculate_cpu_khz(v

extern int timer_ack;
extern int no_timer_check;
-extern int no_sync_cmos_clock;
extern int recalibrate_cpu_khz(void);

#ifndef CONFIG_PARAVIRT

--