On 13.04.21 09:16, Wanpeng Li wrote:
> The bugzilla https://bugzilla.kernel.org/show_bug.cgi?id=209831
> reported that the guest time remains 0 when running a while true
> loop in the guest.
>
> The commit 87fa7f3e98a131 ("x86/kvm: Move context tracking where it
> belongs") moves guest_exit_irqoff() close to vmexit breaks the
> tick-based time accouting when the ticks that happen after IRQs are
> disabled are incorrectly accounted to the host/system time. This is
> because we exit the guest state too early.
>
> This patchset splits both context tracking logic and the time accounting
> logic from guest_enter/exit_irqoff(), keep context tracking around the
> actual vmentry/exit code, have the virt time specific helpers which
> can be placed at the proper spots in kvm. In addition, it will not
> break the world outside of x86.
>
> v1 -> v2:
> * split context_tracking from guest_enter/exit_irqoff
> * provide separate vtime accounting functions for consistent
> * place the virt time specific helpers at the proper splot
>
> Suggested-by: Thomas Gleixner <[email protected]>
> Cc: Thomas Gleixner <[email protected]>
> Cc: Sean Christopherson <[email protected]>
> Cc: Michael Tokarev <[email protected]>
>
> Wanpeng Li (3):
> context_tracking: Split guest_enter/exit_irqoff
> context_tracking: Provide separate vtime accounting functions
> x86/kvm: Fix vtime accounting
>
> arch/x86/kvm/svm/svm.c | 6 ++-
> arch/x86/kvm/vmx/vmx.c | 6 ++-
> arch/x86/kvm/x86.c | 1 +
> include/linux/context_tracking.h | 84 +++++++++++++++++++++++++++++++---------
> 4 files changed, 74 insertions(+), 23 deletions(-)
>
The non CONFIG_VIRT_CPU_ACCOUNTING_GEN look good.