kernel-ark/kernel/time
john stultz 17c38b7490 Cache xtime every call to update_wall_time
This avoids xtime lag seen with dynticks, because while 'xtime' itself
is still not updated often, we keep a 'xtime_cache' variable around that
contains the approximate real-time that _is_ updated each time we do a
'update_wall_time()', and is thus never off by more than one tick.

IOW, this restores the original semantics for 'xtime' users, as long as
you use the proper abstraction functions (ie 'current_kernel_time()' or
'get_seconds()' depending on whether you want a timespec or just the
seconds field).

[ Updated Patch.  As penance for my sins I've also yanked another #ifdef
  that was added to avoid the xtime lag w/ hrtimers.  ]

Signed-off-by: John Stultz <johnstul@us.ibm.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-07-25 10:17:44 -07:00
..
clockevents.c
clocksource.c
jiffies.c
Kconfig
Makefile
ntp.c NTP: move the cmos update code into ntp.c 2007-07-21 17:49:15 -07:00
tick-broadcast.c
tick-common.c
tick-internal.h
tick-oneshot.c highres: improve debug output 2007-07-21 17:49:15 -07:00
tick-sched.c
timekeeping.c Cache xtime every call to update_wall_time 2007-07-25 10:17:44 -07:00
timer_list.c
timer_stats.c