From 82644459c592a28a3eab682f9b88d81019ddfe8b Mon Sep 17 00:00:00 2001 From: Thomas Gleixner Date: Sat, 21 Jul 2007 04:37:37 -0700 Subject: [PATCH] NTP: move the cmos update code into ntp.c 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. [akpm@linux-foundation.org: build fixes] Signed-off-by: Thomas Gleixner Cc: Chris Wright Cc: Ingo Molnar Cc: john stultz Cc: David Miller Cc: Roman Zippel Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- 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 | 3 +++ kernel/time/ntp.c | 59 +++++++++++++++++++++++++++++++++++++++++++--- 7 files changed, 71 insertions(+), 103 deletions(-) diff --git a/arch/i386/Kconfig b/arch/i386/Kconfig index 7a11b90..361aca8 100644 --- a/arch/i386/Kconfig +++ b/arch/i386/Kconfig @@ -18,6 +18,10 @@ config GENERIC_TIME bool default y +config GENERIC_CMOS_UPDATE + bool + default y + config CLOCKSOURCE_WATCHDOG bool default y diff --git a/arch/i386/kernel/time.c b/arch/i386/kernel/time.c index a665df6..19a6c67 100644 --- a/arch/i386/kernel/time.c +++ b/arch/i386/kernel/time.c @@ -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); diff --git a/arch/sparc64/Kconfig b/arch/sparc64/Kconfig index f1cc556..33dabf5 100644 --- a/arch/sparc64/Kconfig +++ b/arch/sparc64/Kconfig @@ -23,6 +23,10 @@ config GENERIC_TIME bool default y +config GENERIC_CMOS_UPDATE + bool + default y + config GENERIC_CLOCKEVENTS bool default y diff --git a/arch/sparc64/kernel/time.c b/arch/sparc64/kernel/time.c index 87c10a7..49063ca 100644 --- a/arch/sparc64/kernel/time.c +++ b/arch/sparc64/kernel/time.c @@ -403,58 +403,9 @@ static struct sparc64_tick_ops hbtick_operations __read_mostly = { 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). */ diff --git a/include/asm-i386/timer.h b/include/asm-i386/timer.h index 51a713e..b371667 100644 --- a/include/asm-i386/timer.h +++ b/include/asm-i386/timer.h @@ -11,7 +11,6 @@ unsigned long native_calculate_cpu_khz(void); extern int timer_ack; extern int no_timer_check; -extern int no_sync_cmos_clock; extern int recalibrate_cpu_khz(void); #ifndef CONFIG_PARAVIRT diff --git a/include/linux/time.h b/include/linux/time.h index ec3b0ce..e6aea51 100644 --- a/include/linux/time.h +++ b/include/linux/time.h @@ -4,6 +4,7 @@ #include #ifdef __KERNEL__ +# include # include #endif @@ -94,6 +95,8 @@ 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) diff --git a/kernel/time/ntp.c b/kernel/time/ntp.c index b5e3525..cd91237 100644 --- a/kernel/time/ntp.c +++ b/kernel/time/ntp.c @@ -10,6 +10,7 @@ #include #include +#include #include #include #include @@ -175,12 +176,64 @@ 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) +{ + 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) { - return; + 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. */ @@ -345,6 +398,6 @@ leave: if ((time_status & (STA_UNSYNC|STA_CLOCKERR)) != 0) txc->stbcnt = 0; write_sequnlock_irq(&xtime_lock); do_gettimeofday(&txc->time); - notify_arch_cmos_timer(); + notify_cmos_timer(); return(result); } -- 2.7.4