sched: Simplify ->cpu_power initialization

The code in update_group_power() does what init_sched_groups_power()
does and more, so remove the special init_ code and call the generic
code instead.

Also move the sd->span_weight initialization because
update_group_power() needs it.

Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Nick Piggin <npiggin@kernel.dk>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Link: http://lkml.kernel.org/r/20110407122941.875856012@chello.nl
Signed-off-by: Ingo Molnar <mingo@elte.hu>

1 files changed, 5 insertions, 39 deletions

diff --git a/kernel/sched.c b/kernel/sched.c
index d3e183c85f49..50d5fd33e8d5 100644
--- a/kernel/sched.c
+++ b/kernel/sched.c
@@ -6679,9 +6679,6 @@ cpu_attach_domain(struct sched_domain *sd, struct root_domain *rd, int cpu)
         struct rq *rq = cpu_rq(cpu);
         struct sched_domain *tmp;
 
-        for (tmp = sd; tmp; tmp = tmp->parent)
-                tmp->span_weight = cpumask_weight(sched_domain_span(tmp));
-
         /* Remove the sched domains which do not contribute to scheduling. */
         for (tmp = sd; tmp; ) {
                 struct sched_domain *parent = tmp->parent;
@@ -7159,11 +7156,6 @@ static void free_sched_groups(const struct cpumask *cpu_map,
  */
 static void init_sched_groups_power(int cpu, struct sched_domain *sd)
 {
-        struct sched_domain *child;
-        struct sched_group *group;
-        long power;
-        int weight;
-
         WARN_ON(!sd || !sd->groups);
 
         if (cpu != group_first_cpu(sd->groups))
@@ -7171,36 +7163,7 @@ static void init_sched_groups_power(int cpu, struct sched_domain *sd)
 
         sd->groups->group_weight = cpumask_weight(sched_group_cpus(sd->groups));
 
-        child = sd->child;
-
-        sd->groups->cpu_power = 0;
-
-        if (!child) {
-                power = SCHED_LOAD_SCALE;
-                weight = cpumask_weight(sched_domain_span(sd));
-                /*
-                 * SMT siblings share the power of a single core.
-                 * Usually multiple threads get a better yield out of
-                 * that one core than a single thread would have,
-                 * reflect that in sd->smt_gain.
-                 */
-                if ((sd->flags & SD_SHARE_CPUPOWER) && weight > 1) {
-                        power *= sd->smt_gain;
-                        power /= weight;
-                        power >>= SCHED_LOAD_SHIFT;
-                }
-                sd->groups->cpu_power += power;
-                return;
-        }
-
-        /*
-         * Add cpu_power of each child group to this groups cpu_power.
-         */
-        group = child->groups;
-        do {
-                sd->groups->cpu_power += group->cpu_power;
-                group = group->next;
-        } while (group != child->groups);
+        update_group_power(sd, cpu);
 }
 
 /*
@@ -7507,7 +7470,7 @@ static int __build_sched_domains(const struct cpumask *cpu_map,
 {
         enum s_alloc alloc_state = sa_none;
         struct s_data d;
-        struct sched_domain *sd;
+        struct sched_domain *sd, *tmp;
         int i;
 #ifdef CONFIG_NUMA
         d.sd_allnodes = 0;
@@ -7530,6 +7493,9 @@ static int __build_sched_domains(const struct cpumask *cpu_map,
                 sd = __build_book_sched_domain(&d, cpu_map, attr, sd, i);
                 sd = __build_mc_sched_domain(&d, cpu_map, attr, sd, i);
                 sd = __build_smt_sched_domain(&d, cpu_map, attr, sd, i);
+
+                for (tmp = sd; tmp; tmp = tmp->parent)
+                        tmp->span_weight = cpumask_weight(sched_domain_span(tmp));
         }
 
         for_each_cpu(i, cpu_map) {