lkml.org 
[lkml]   [2005]   [Jan]   [8]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
SubjectPatch 1/3: Reduce number of get_cmos_time_calls.
From
Date
Reduce the number of calls to get_cmos_time. Since get_cmos_time waits
for the start of a new second, two consecutive calls add one full second
to the time to suspend/resume.

Signed-off-by: Nigel Cunningham <ncunningham@linuxmail.org>

diff -ruNp 911-old/arch/i386/kernel/time.c 911-new/arch/i386/kernel/time.c
--- 911-old/arch/i386/kernel/time.c 2005-01-08 19:36:46.107382632 +1100
+++ 911-new/arch/i386/kernel/time.c 2005-01-08 19:36:25.439524624 +1100
@@ -326,9 +326,11 @@ static int timer_suspend(struct sys_devi
/*
* Estimate time zone so that set_time can update the clock
*/
- clock_cmos_diff = -get_cmos_time();
+ long cmos_time = get_cmos_time();
+
+ clock_cmos_diff = -cmos_time;
clock_cmos_diff += get_seconds();
- sleep_start = get_cmos_time();
+ sleep_start = cmos_time;
return 0;
}

@@ -337,13 +339,15 @@ static int timer_resume(struct sys_devic
unsigned long flags;
unsigned long sec;
unsigned long sleep_length;
+ unsigned long cmos_time;

#ifdef CONFIG_HPET_TIMER
if (is_hpet_enabled())
hpet_reenable();
#endif
- sec = get_cmos_time() + clock_cmos_diff;
- sleep_length = (get_cmos_time() - sleep_start) * HZ;
+ cmos_time = get_cmos_time();
+ sec = cmos_time + clock_cmos_diff;
+ sleep_length = (cmos_time - sleep_start) * HZ;
write_seqlock_irqsave(&xtime_lock, flags);
xtime.tv_sec = sec;
xtime.tv_nsec = 0;

-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/

\
 
 \ /
  Last update: 2005-03-22 14:09    [W:0.097 / U:0.396 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site