On 02/08/2017 16:38, Denis Plotnikov wrote: > V4: > * removed "is stable" function with vague definition of stability > there is the only function which does time with cycle stamp getting > * some variables renamed > * some patches split into smaller once > * atomic64_t usage is replaced with atomic_t Thanks. This looks good from the KVM point of view. Let's see what the timekeeping guys think. Paolo > 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 (10): > timekeeper: introduce extended clocksource reading callback > timekeeper: introduce boot field in system_time_snapshot > timekeeper: use the extended reading function on snapshot acquiring > tsc: implement the extended tsc 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 parameters to store stamp data in pvclock reading > function > pvclock: add clocksource change notification on changing of tsc stable > bit > kvmclock: implement the extended reading function > > arch/x86/include/asm/kvm_host.h | 2 +- > arch/x86/include/asm/pvclock.h | 3 +- > arch/x86/kernel/kvmclock.c | 19 +++- > arch/x86/kernel/pvclock.c | 37 +++++- > arch/x86/kernel/tsc.c | 10 ++ > arch/x86/kvm/trace.h | 31 ++--- > arch/x86/kvm/x86.c | 242 ++++++++-------------------------------- > arch/x86/xen/time.c | 2 +- > include/linux/clocksource.h | 11 +- > include/linux/cs_notifier.h | 17 +++ > include/linux/timekeeping.h | 5 + > kernel/time/timekeeping.c | 68 ++++++++++- > 12 files changed, 219 insertions(+), 228 deletions(-) > create mode 100644 include/linux/cs_notifier.h >
