]> git.baikalelectronics.ru Git - kernel.git/commit
KVM: x86: limit difference between kvmclock updates
authorMarcelo Tosatti <mtosatti@redhat.com>
Thu, 9 May 2013 23:21:41 +0000 (20:21 -0300)
committerGleb Natapov <gleb@redhat.com>
Wed, 15 May 2013 17:36:09 +0000 (20:36 +0300)
commita6cffff09aa8ca078ad2a7002ca3b70146cf0376
treec9b86974498fb39210c355171c01afbae513bb59
parent669d155a66d9d1192dc5eecd75302e625c64982a
KVM: x86: limit difference between kvmclock updates

kvmclock updates which are isolated to a given vcpu, such as vcpu->cpu
migration, should not allow system_timestamp from the rest of the vcpus
to remain static. Otherwise ntp frequency correction applies to one
vcpu's system_timestamp but not the others.

So in those cases, request a kvmclock update for all vcpus. The worst
case for a remote vcpu to update its kvmclock is then bounded by maximum
nohz sleep latency.

Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Gleb Natapov <gleb@redhat.com>
arch/x86/kvm/x86.c
include/linux/kvm_host.h