lkml.org 
[lkml]   [2021]   [Apr]   [20]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
SubjectRe: [PATCH v3 2/9] context_tracking: Move guest exit vtime accounting to separate helpers
From
Date


On 16.04.21 00:20, Sean Christopherson wrote:
> From: Wanpeng Li <wanpengli@tencent.com>
>
> Provide separate vtime accounting functions for guest exit instead of
> open coding the logic within the context tracking code. This will allow
> KVM x86 to handle vtime accounting slightly differently when using
> tick-based accounting.
>
> Suggested-by: Thomas Gleixner <tglx@linutronix.de>
> Cc: Thomas Gleixner <tglx@linutronix.de>
> Cc: Michael Tokarev <mjt@tls.msk.ru>
> Cc: Christian Borntraeger <borntraeger@de.ibm.com>
> Signed-off-by: Wanpeng Li <wanpengli@tencent.com>
> Co-developed-by: Sean Christopherson <seanjc@google.com>
> Signed-off-by: Sean Christopherson <seanjc@google.com>

Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com>

> ---
> include/linux/context_tracking.h | 24 +++++++++++++++++-------
> 1 file changed, 17 insertions(+), 7 deletions(-)
>
> diff --git a/include/linux/context_tracking.h b/include/linux/context_tracking.h
> index 200d30cb3a82..7cf03a8e5708 100644
> --- a/include/linux/context_tracking.h
> +++ b/include/linux/context_tracking.h
> @@ -137,15 +137,20 @@ static __always_inline void context_tracking_guest_exit_irqoff(void)
> __context_tracking_exit(CONTEXT_GUEST);
> }
>
> -static __always_inline void guest_exit_irqoff(void)
> +static __always_inline void vtime_account_guest_exit(void)
> {
> - context_tracking_guest_exit_irqoff();
> -
> - instrumentation_begin();
> if (vtime_accounting_enabled_this_cpu())
> vtime_guest_exit(current);
> else
> current->flags &= ~PF_VCPU;
> +}
> +
> +static __always_inline void guest_exit_irqoff(void)
> +{
> + context_tracking_guest_exit_irqoff();
> +
> + instrumentation_begin();
> + vtime_account_guest_exit();
> instrumentation_end();
> }
>
> @@ -166,12 +171,17 @@ static __always_inline void guest_enter_irqoff(void)
>
> static __always_inline void context_tracking_guest_exit_irqoff(void) { }
>
> -static __always_inline void guest_exit_irqoff(void)
> +static __always_inline void vtime_account_guest_exit(void)
> {
> - instrumentation_begin();
> - /* Flush the guest cputime we spent on the guest */
> vtime_account_kernel(current);
> current->flags &= ~PF_VCPU;
> +}
> +
> +static __always_inline void guest_exit_irqoff(void)
> +{
> + instrumentation_begin();
> + /* Flush the guest cputime we spent on the guest */
> + vtime_account_guest_exit();
> instrumentation_end();
> }
> #endif /* CONFIG_VIRT_CPU_ACCOUNTING_GEN */
>

\
 
 \ /
  Last update: 2021-04-20 20:49    [W:0.482 / U:0.780 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site