Re: [PATCH 3 of 6 v2] xen: sched_credit: use current_on_cpu() when appropriate

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

On 12/12/12 02:52, Dario Faggioli wrote:
> Defined by the previous change, using it wherever it is appropriate
> throughout sched_credit.c makes the code easier to read.

Hmm, I hadn't read this patch when I commented about removing the macro 
from the first patch. :-)

I personally think that using vc->processor is better in that patch 
anyway; but using this macro elsewhere is probably fine.

I think from a taste point of view, I would have put this patch, with 
the new definition, as the first patch in the series, and the had the 
second patch just use it.

I'll go back and respond to Jan's comment about the macro.

  -George

>
> Signed-off-by: Dario Faggioli <dario.faggioli@citrix.com>
>
> diff --git a/xen/common/sched_credit.c b/xen/common/sched_credit.c
> --- a/xen/common/sched_credit.c
> +++ b/xen/common/sched_credit.c
> @@ -231,7 +231,7 @@ static void burn_credits(struct csched_v
>       unsigned int credits;
>   
>       /* Assert svc is current */
> -    ASSERT(svc==CSCHED_VCPU(per_cpu(schedule_data, svc->vcpu->processor).curr));
> +    ASSERT( svc == CSCHED_VCPU(current_on_cpu(svc->vcpu->processor)) );
>   
>       if ( (delta = now - svc->start_time) <= 0 )
>           return;
> @@ -249,8 +249,7 @@ DEFINE_PER_CPU(unsigned int, last_tickle
>   static inline void
>   __runq_tickle(unsigned int cpu, struct csched_vcpu *new)
>   {
> -    struct csched_vcpu * const cur =
> -        CSCHED_VCPU(per_cpu(schedule_data, cpu).curr);
> +    struct csched_vcpu * const cur = CSCHED_VCPU(current_on_cpu(cpu));
>       struct csched_private *prv = CSCHED_PRIV(per_cpu(scheduler, cpu));
>       cpumask_t mask, idle_mask;
>       int idlers_empty;
> @@ -387,7 +386,7 @@ csched_alloc_pdata(const struct schedule
>           per_cpu(schedule_data, cpu).sched_priv = spc;
>   
>       /* Start off idling... */
> -    BUG_ON(!is_idle_vcpu(per_cpu(schedule_data, cpu).curr));
> +    BUG_ON(!is_idle_vcpu(current_on_cpu(cpu)));
>       cpumask_set_cpu(cpu, prv->idlers);
>   
>       spin_unlock_irqrestore(&prv->lock, flags);
> @@ -730,7 +729,7 @@ csched_vcpu_sleep(const struct scheduler
>   
>       BUG_ON( is_idle_vcpu(vc) );
>   
> -    if ( per_cpu(schedule_data, vc->processor).curr == vc )
> +    if ( current_on_cpu(vc->processor) == vc )
>           cpu_raise_softirq(vc->processor, SCHEDULE_SOFTIRQ);
>       else if ( __vcpu_on_runq(svc) )
>           __runq_remove(svc);
> @@ -744,7 +743,7 @@ csched_vcpu_wake(const struct scheduler
>   
>       BUG_ON( is_idle_vcpu(vc) );
>   
> -    if ( unlikely(per_cpu(schedule_data, cpu).curr == vc) )
> +    if ( unlikely(current_on_cpu(cpu) == vc) )
>       {
>           SCHED_STAT_CRANK(vcpu_wake_running);
>           return;
> @@ -1213,7 +1212,7 @@ static struct csched_vcpu *
>   csched_runq_steal(int peer_cpu, int cpu, int pri)
>   {
>       const struct csched_pcpu * const peer_pcpu = CSCHED_PCPU(peer_cpu);
> -    const struct vcpu * const peer_vcpu = per_cpu(schedule_data, peer_cpu).curr;
> +    const struct vcpu * const peer_vcpu = current_on_cpu(peer_cpu);
>       struct csched_vcpu *speer;
>       struct list_head *iter;
>       struct vcpu *vc;
> @@ -1502,7 +1501,7 @@ csched_dump_pcpu(const struct scheduler
>       printk("core=%s\n", cpustr);
>   
>       /* current VCPU */
> -    svc = CSCHED_VCPU(per_cpu(schedule_data, cpu).curr);
> +    svc = CSCHED_VCPU(current_on_cpu(cpu));
>       if ( svc )
>       {
>           printk("\trun: ");