clockevents: Make minimum delay adjustments configurable
authorMartin Schwidefsky <schwidefsky@de.ibm.com>
Tue, 23 Aug 2011 13:29:42 +0000 (15:29 +0200)
committerThomas Gleixner <tglx@linutronix.de>
Thu, 8 Sep 2011 09:10:56 +0000 (11:10 +0200)
commitd1748302f70be7469809809283fe164156a34231
treec81137f4126f2fe1451c28441415c1cd0fa0f7cd
parent29c158e81c733ac7d6a75c5ee929f34fb9f92983
clockevents: Make minimum delay adjustments configurable

The automatic increase of the min_delta_ns of a clockevents device
should be done in the clockevents code as the minimum delay is an
attribute of the clockevents device.

In addition not all architectures want the automatic adjustment, on a
massively virtualized system it can happen that the programming of a
clock event fails several times in a row because the virtual cpu has
been rescheduled quickly enough. In that case the minimum delay will
erroneously be increased with no way back. The new config symbol
GENERIC_CLOCKEVENTS_MIN_ADJUST is used to enable the automatic
adjustment. The config option is selected only for x86.

Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: john stultz <johnstul@us.ibm.com>
Link: http://lkml.kernel.org/r/20110823133142.494157493@de.ibm.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
arch/x86/Kconfig
include/linux/clockchips.h
kernel/time/Kconfig
kernel/time/clockevents.c
kernel/time/tick-broadcast.c
kernel/time/tick-common.c
kernel/time/tick-internal.h
kernel/time/tick-oneshot.c