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yaml
---
r: 62368
b: refs/heads/master
c: af74522
h: refs/heads/master
v: v3
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Thomas Gleixner authored and Linus Torvalds committed Jul 22, 2007
1 parent 2e5f72d commit c4806df
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Showing 3 changed files with 14 additions and 17 deletions.
2 changes: 1 addition & 1 deletion [refs]
Original file line number Diff line number Diff line change
@@ -1,2 +1,2 @@
---
refs/heads/master: 55f93afd89fe6b9b9e12cfb2d3eb1a68e21f529e
refs/heads/master: af74522ab782c718783b9d85d6d53b8cbf0c7b17
4 changes: 4 additions & 0 deletions trunk/arch/x86_64/Kconfig
Original file line number Diff line number Diff line change
Expand Up @@ -32,6 +32,10 @@ config GENERIC_TIME_VSYSCALL
bool
default y

config GENERIC_CMOS_UPDATE
bool
default y

config ZONE_DMA32
bool
default y
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25 changes: 9 additions & 16 deletions trunk/arch/x86_64/kernel/time.c
Original file line number Diff line number Diff line change
Expand Up @@ -80,8 +80,9 @@ EXPORT_SYMBOL(profile_pc);
* sheet for details.
*/

static void set_rtc_mmss(unsigned long nowtime)
static int set_rtc_mmss(unsigned long nowtime)
{
int retval = 0;
int real_seconds, real_minutes, cmos_minutes;
unsigned char control, freq_select;

Expand Down Expand Up @@ -121,6 +122,7 @@ static void set_rtc_mmss(unsigned long nowtime)
if (abs(real_minutes - cmos_minutes) >= 30) {
printk(KERN_WARNING "time.c: can't update CMOS clock "
"from %d to %d\n", cmos_minutes, real_minutes);
retval = -1;
} else {
BIN_TO_BCD(real_seconds);
BIN_TO_BCD(real_minutes);
Expand All @@ -140,12 +142,17 @@ static void set_rtc_mmss(unsigned long nowtime)
CMOS_WRITE(freq_select, RTC_FREQ_SELECT);

spin_unlock(&rtc_lock);

return retval;
}

int update_persistent_clock(struct timespec now)
{
return set_rtc_mmss(now.tv_sec);
}

void main_timer_handler(void)
{
static unsigned long rtc_update = 0;
/*
* Here we are in the timer irq handler. We have irqs locally disabled (so we
* don't need spin_lock_irqsave()) but we don't know if the timer_bh is running
Expand Down Expand Up @@ -173,20 +180,6 @@ void main_timer_handler(void)
if (!using_apic_timer)
smp_local_timer_interrupt();

/*
* If we have an externally synchronized Linux clock, then update CMOS clock
* accordingly every ~11 minutes. set_rtc_mmss() will be called in the jiffy
* closest to exactly 500 ms before the next second. If the update fails, we
* don't care, as it'll be updated on the next turn, and the problem (time way
* off) isn't likely to go away much sooner anyway.
*/

if (ntp_synced() && xtime.tv_sec > rtc_update &&
abs(xtime.tv_nsec - 500000000) <= tick_nsec / 2) {
set_rtc_mmss(xtime.tv_sec);
rtc_update = xtime.tv_sec + 660;
}

write_sequnlock(&xtime_lock);
}

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