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Subject[patch 2/8] rtc: mc146818: Reduce spinlock section in mc146818_set_time()
No need to hold the lock and disable interrupts for doing math.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
---
drivers/rtc/rtc-mc146818-lib.c | 6 ++----
1 file changed, 2 insertions(+), 4 deletions(-)

--- a/drivers/rtc/rtc-mc146818-lib.c
+++ b/drivers/rtc/rtc-mc146818-lib.c
@@ -135,7 +135,6 @@ int mc146818_set_time(struct rtc_time *t
if (yrs > 255) /* They are unsigned */
return -EINVAL;

- spin_lock_irqsave(&rtc_lock, flags);
#ifdef CONFIG_MACH_DECSTATION
real_yrs = yrs;
leap_yr = ((!((yrs + 1900) % 4) && ((yrs + 1900) % 100)) ||
@@ -164,10 +163,8 @@ int mc146818_set_time(struct rtc_time *t
/* These limits and adjustments are independent of
* whether the chip is in binary mode or not.
*/
- if (yrs > 169) {
- spin_unlock_irqrestore(&rtc_lock, flags);
+ if (yrs > 169)
return -EINVAL;
- }

if (yrs >= 100)
yrs -= 100;
@@ -183,6 +180,7 @@ int mc146818_set_time(struct rtc_time *t
century = bin2bcd(century);
}

+ spin_lock_irqsave(&rtc_lock, flags);
save_control = CMOS_READ(RTC_CONTROL);
CMOS_WRITE((save_control|RTC_SET), RTC_CONTROL);
save_freq_select = CMOS_READ(RTC_FREQ_SELECT);
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