sched: Fix the place where group powers are updated
Gautham R Shenoy [Wed, 20 Jan 2010 20:02:44 +0000 (14:02 -0600)]
We want to update the sched_group_powers when balance_cpu == this_cpu.

Currently the group powers are updated only if the balance_cpu is the
first CPU in the local group. But balance_cpu = this_cpu could also be
the first idle cpu in the group. Hence fix the place where the group
powers are updated.

Signed-off-by: Gautham R Shenoy <ego@in.ibm.com>
Signed-off-by: Joel Schopp <jschopp@austin.ibm.com>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
LKML-Reference: <1264017764.5717.127.camel@jschopp-laptop>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

kernel/sched_fair.c

index 0b482f5..22231cc 100644 (file)
@@ -2418,11 +2418,8 @@ static inline void update_sg_lb_stats(struct sched_domain *sd,
        unsigned long sum_avg_load_per_task;
        unsigned long avg_load_per_task;
 
-       if (local_group) {
+       if (local_group)
                balance_cpu = group_first_cpu(group);
-               if (balance_cpu == this_cpu)
-                       update_group_power(sd, this_cpu);
-       }
 
        /* Tally up the load of all CPUs in the group */
        sum_avg_load_per_task = avg_load_per_task = 0;
@@ -2470,6 +2467,8 @@ static inline void update_sg_lb_stats(struct sched_domain *sd,
                return;
        }
 
+       update_group_power(sd, this_cpu);
+
        /* Adjust by relative CPU power of the group */
        sgs->avg_load = (sgs->group_load * SCHED_LOAD_SCALE) / group->cpu_power;