Re: [PATCH v2 02/16] xen: sched: move up the trace record for vcpu_wake and vcpu_sleep

[George Dunlap <george.dunlap@citrix.com>]

On 16/02/16 18:11, Dario Faggioli wrote:
> vcpu_wake() and vcpu_sleep() are called before the specific
> schedulers wakeup and sleep routines (in fact, it is them
> that calls those specific routine).
> 
> Make the trace reflect that, by moving the records up. In
> fact, it is more natural and easy to find the record of
> the event (e.g., the wakeup) *before* the records of the
> actions that deals with the event itself.
> 
> Signed-off-by: Dario Faggioli <dario.faggioli@citrix.com>
> Reviewed-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>

Acked-by: George Dunlap <george.dunlap@citrix.com>

> ---
> Cc: George Dunlap <george.dunlap@citrix.com>
> ---
>  xen/common/schedule.c |   16 ++++++++++------
>  1 file changed, 10 insertions(+), 6 deletions(-)
> 
> diff --git a/xen/common/schedule.c b/xen/common/schedule.c
> index 7306d71..c87922f 100644
> --- a/xen/common/schedule.c
> +++ b/xen/common/schedule.c
> @@ -381,7 +381,11 @@ void sched_destroy_domain(struct domain *d)
>  void vcpu_sleep_nosync(struct vcpu *v)
>  {
>      unsigned long flags;
> -    spinlock_t *lock = vcpu_schedule_lock_irqsave(v, &flags);
> +    spinlock_t *lock;
> +
> +    TRACE_2D(TRC_SCHED_SLEEP, v->domain->domain_id, v->vcpu_id);
> +
> +    lock = vcpu_schedule_lock_irqsave(v, &flags);
>  
>      if ( likely(!vcpu_runnable(v)) )
>      {
> @@ -392,8 +396,6 @@ void vcpu_sleep_nosync(struct vcpu *v)
>      }
>  
>      vcpu_schedule_unlock_irqrestore(lock, flags, v);
> -
> -    TRACE_2D(TRC_SCHED_SLEEP, v->domain->domain_id, v->vcpu_id);
>  }
>  
>  void vcpu_sleep_sync(struct vcpu *v)
> @@ -409,7 +411,11 @@ void vcpu_sleep_sync(struct vcpu *v)
>  void vcpu_wake(struct vcpu *v)
>  {
>      unsigned long flags;
> -    spinlock_t *lock = vcpu_schedule_lock_irqsave(v, &flags);
> +    spinlock_t *lock;
> +
> +    TRACE_2D(TRC_SCHED_WAKE, v->domain->domain_id, v->vcpu_id);
> +
> +    lock = vcpu_schedule_lock_irqsave(v, &flags);
>  
>      if ( likely(vcpu_runnable(v)) )
>      {
> @@ -424,8 +430,6 @@ void vcpu_wake(struct vcpu *v)
>      }
>  
>      vcpu_schedule_unlock_irqrestore(lock, flags, v);
> -
> -    TRACE_2D(TRC_SCHED_WAKE, v->domain->domain_id, v->vcpu_id);
>  }
>  
>  void vcpu_unblock(struct vcpu *v)
>