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linux/kernel/time
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Ingo Molnar e4e4e534fa sched clock: revert various sched_clock() changes 
Found an interactivity problem on a quad core test-system - simple
CPU loops would occasionally delay the system un an unacceptable way.

After much debugging with Peter Zijlstra it turned out that the problem
is caused by the string of sched_clock() changes - they caused the CPU
clock to jump backwards a bit - which confuses the scheduler arithmetics.

(which is unsigned for performance reasons)

So revert:

 # c300ba2: sched_clock: and multiplier for TSC to gtod drift
 # c0c8773: sched_clock: only update deltas with local reads.
 # af52a90: sched_clock: stop maximum check on NO HZ
 # f7cce27: sched_clock: widen the max and min time

This solves the interactivity problems.

Signed-off-by: Ingo Molnar <mingo@elte.hu>
Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Acked-by: Mike Galbraith <efault@gmx.de>
2008-07-31 17:20:29 +02:00
..
clockevents.c time: fix typo in comments 2008-02-08 09:22:29 -08:00
clocksource.c Merge branch 'cpus4096-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip 2008-07-23 18:37:44 -07:00
jiffies.c
Kconfig clockevents: Allow build w/o run-tine usage for migration purposes 2007-10-12 23:04:05 +02:00
Makefile clockevents: Allow build w/o run-tine usage for migration purposes 2007-10-12 23:04:05 +02:00
ntp.c ntp: handle leap second via timer 2008-05-01 08:03:59 -07:00
tick-broadcast.c Merge branch 'linus' into cpus4096 2008-07-16 00:29:07 +02:00
tick-common.c cpumask: change cpumask_of_cpu_ptr to use new cpumask_of_cpu 2008-07-26 16:40:33 +02:00
tick-internal.h timer: clean up tick-broadcast.c 2008-01-30 13:30:01 +01:00
tick-oneshot.c [S390] genirq/clockevents: move irq affinity prototypes/inlines to interrupt.h 2008-04-17 07:47:05 +02:00
tick-sched.c sched clock: revert various sched_clock() changes 2008-07-31 17:20:29 +02:00
timekeeping.c ntp: handle leap second via timer 2008-05-01 08:03:59 -07:00
timer_list.c kernel: use non-racy method for proc entries creation 2008-04-29 08:06:22 -07:00
timer_stats.c kernel: use non-racy method for proc entries creation 2008-04-29 08:06:22 -07:00