V3:
Changing the timekeeper interface for clocksource reading looks like
an overkill to achive the goal of getting cycles stamp for KVM.
Instead extend the timekeeping interface and add functions which provide
necessary data: read clocksource with cycles stamp, check whether the
clock source is stable.
Use those functions and improve existing timekeeper functionality to
replace pvclock_gtod_copy scheme in masterclock data calculation.
V2:
The main goal is to make L2 kvm-clock be stable when it's running over L1
with stable kvm-clock.
The patch series is for x86 architecture only. If the series is approved
I'll do changes for other architectures but I don't have an ability to
compile and check for every single on (help needed)
The patch series do the following:
* change timekeeper interface to get cycles stamp value from
the timekeeper
* get rid of pvclock copy in KVM by using the changed timekeeper
interface: get time and cycles right from the timekeeper
* make KVM recognize a stable kvm-clock as stable clocksource
and use the KVM masterclock in this case, which means making
L2 stable when running over stable L1 kvm-clock
Denis Plotnikov (6):
pvclock: add parameter to store cycles stamp to pvclock reading
function
KVM: x86: switch to masterclock update using timekeeper functionality
timekeeper: add clocksource change notifier
KVM: x86: remove not used pvclock_gtod_copy
pvclock: add clocksource change notification on changing of tsc stable
bit
kvmclock: add the clocksource stability querying function
arch/x86/include/asm/kvm_host.h | 2 +-
arch/x86/include/asm/pvclock.h | 2 +-
arch/x86/kernel/kvmclock.c | 26 ++++-
arch/x86/kernel/pvclock.c | 31 ++++-
arch/x86/kernel/tsc.c | 6 +
arch/x86/kvm/trace.h | 31 ++---
arch/x86/kvm/x86.c | 242 ++++++++--------------------------------
arch/x86/xen/time.c | 2 +-
include/linux/clocksource.h | 3 +
include/linux/cs_notifier.h | 17 +++
include/linux/timekeeping.h | 2 +
kernel/time/timekeeping.c | 72 +++++++++++-
12 files changed, 209 insertions(+), 227 deletions(-)
create mode 100644 include/linux/cs_notifier.h
--
2.7.4
