linux-kernel-test/arch/x86
Salman Qazi 4cecf6d401 sched, x86: Avoid unnecessary overflow in sched_clock
(Added the missing signed-off-by line)

In hundreds of days, the __cycles_2_ns calculation in sched_clock
has an overflow.  cyc * per_cpu(cyc2ns, cpu) exceeds 64 bits, causing
the final value to become zero.  We can solve this without losing
any precision.

We can decompose TSC into quotient and remainder of division by the
scale factor, and then use this to convert TSC into nanoseconds.

Signed-off-by: Salman Qazi <sqazi@google.com>
Acked-by: John Stultz <johnstul@us.ibm.com>
Reviewed-by: Paul Turner <pjt@google.com>
Cc: stable@kernel.org
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/20111115221121.7262.88871.stgit@dungbeetle.mtv.corp.google.com
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2011-11-16 19:51:25 +01:00
..
boot doc: fix broken references 2011-09-27 18:08:04 +02:00
configs iommu: Rename the DMAR and INTR_REMAP config options 2011-09-21 10:22:03 +02:00
crypto Merge branch 'modsplit-Oct31_2011' of git://git.kernel.org/pub/scm/linux/kernel/git/paulg/linux 2011-11-06 19:44:47 -08:00
ia32 Cross Memory Attach 2011-10-31 17:30:44 -07:00
include/asm sched, x86: Avoid unnecessary overflow in sched_clock 2011-11-16 19:51:25 +01:00
kernel Merge branch 'upstream/jump-label-noearly' of git://git.kernel.org/pub/scm/linux/kernel/git/jeremy/xen 2011-11-06 20:20:46 -08:00
kvm Merge branch 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/joro/iommu 2011-10-30 15:46:19 -07:00
lguest lguest: add export.h to lguest files for THIS_MODULE/EXPORT_SYMBOL 2011-10-31 19:32:13 -04:00
lib x86: Fix insn decoder for longer instruction 2011-10-10 09:05:51 +02:00
math-emu
mm thp: share get_huge_page_tail() 2011-11-02 16:06:58 -07:00
net
oprofile Merge branch 'perf-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2011-10-26 17:03:38 +02:00
pci x86: Fix files explicitly requiring export.h for EXPORT_SYMBOL/THIS_MODULE 2011-10-31 19:30:35 -04:00
platform bma023: Add SFI translation for this device 2011-11-11 23:58:58 -02:00
power x86: Fix files explicitly requiring export.h for EXPORT_SYMBOL/THIS_MODULE 2011-10-31 19:30:35 -04:00
tools
um Merge branch 'trivial' of git://git.kernel.org/pub/scm/linux/kernel/git/mmarek/kbuild 2011-11-06 18:54:53 -08:00
vdso Merge branch 'x86-cpu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2011-10-28 05:03:12 -07:00
video x86: fix up files really needing to include module.h 2011-10-31 19:30:36 -04:00
xen Merge branch 'upstream/xen-settime' of git://git.kernel.org/pub/scm/linux/kernel/git/jeremy/xen 2011-11-06 20:15:05 -08:00
.gitignore
Kbuild
Kconfig Merge branch 'trivial' of git://git.kernel.org/pub/scm/linux/kernel/git/mmarek/kbuild 2011-11-06 18:54:53 -08:00
Kconfig.cpu
Kconfig.debug doc: fix broken references 2011-09-27 18:08:04 +02:00
Makefile
Makefile_32.cpu
Makefile.um um: take arch/um/sys-x86 to arch/x86/um 2011-11-02 14:15:05 +01:00