Re: [patch 3/3] sched: move sched_avg_update() to update_cpu_load()

[Peter Zijlstra <peterz@infradead.org>]

On Thu, 2010-08-19 at 17:51 -0700, Suresh Siddha wrote:
> 
> From: Suresh Siddha <suresh.b.siddha@intel.com>
> Subject: sched: move sched_avg_update() to update_cpu_load()
> 
> Currently sched_avg_update() (which updates rt_avg stats in the rq) is getting
> called from scale_rt_power() (in the load balance context) which doesn't take
> rq->lock.
> 
> Fix it by moving the sched_avg_update() to more appropriate update_cpu_load()
> where the CFS load gets updated aswell.
> 
> Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com>
> ---
>  kernel/sched.c      |    3 ++-
>  kernel/sched_fair.c |    2 --
>  2 files changed, 2 insertions(+), 3 deletions(-)
> 
> Index: tree/kernel/sched_fair.c
> ===================================================================
> --- tree.orig/kernel/sched_fair.c
> +++ tree/kernel/sched_fair.c
> @@ -2268,8 +2268,6 @@ unsigned long scale_rt_power(int cpu)
>         struct rq *rq = cpu_rq(cpu);
>         u64 total, available;
>  
> -       sched_avg_update(rq);
> -
>         total = sched_avg_period() + (rq->clock - rq->age_stamp);
>         available = total - rq->rt_avg;
>  
> Index: tree/kernel/sched.c
> ===================================================================
> --- tree.orig/kernel/sched.c
> +++ tree/kernel/sched.c
> @@ -3182,6 +3182,8 @@ static void update_cpu_load(struct rq *t
>  
>                 this_rq->cpu_load[i] = (old_load * (scale - 1) + new_load) >> i;
>         }
> +
> +       sched_avg_update(this_rq);
>  }
>  
>  static void update_cpu_load_active(struct rq *this_rq) 

breaks CONFIG_SMP=n builds..

  CC      kernel/sched.o
/usr/src/linux-2.6/kernel/sched.c: In function ‘update_cpu_load’:
/usr/src/linux-2.6/kernel/sched.c:3186: error: implicit declaration of function ‘sched_avg_update’  CC      kernel/sched.o
/usr/src/linux-2.6/kernel/sched.c: In function ‘update_cpu_load’:
/usr/src/linux-2.6/kernel/sched.c:3186: error: implicit declaration of function ‘sched_avg_update’