sched: Update the cpu_power sum during load-balance
In order to prepare for a more dynamic cpu_power, update the
group sum while walking the sched domains during load-balance.
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Tested-by: Andreas Herrmann <andreas.herrmann3@amd.com>
Acked-by: Andreas Herrmann <andreas.herrmann3@amd.com>
Acked-by: Gautham R Shenoy <ego@in.ibm.com>
Cc: Balbir Singh <balbir@in.ibm.com>
LKML-Reference: <20090901083825.985050292@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
diff --git a/kernel/sched.c b/kernel/sched.c
index 9d64cec..ecb4a47 100644
--- a/kernel/sched.c
+++ b/kernel/sched.c
@@ -3699,6 +3699,28 @@
}
#endif /* CONFIG_SCHED_MC || CONFIG_SCHED_SMT */
+static void update_sched_power(struct sched_domain *sd)
+{
+ struct sched_domain *child = sd->child;
+ struct sched_group *group, *sdg = sd->groups;
+ unsigned long power = sdg->__cpu_power;
+
+ if (!child) {
+ /* compute cpu power for this cpu */
+ return;
+ }
+
+ sdg->__cpu_power = 0;
+
+ group = child->groups;
+ do {
+ sdg->__cpu_power += group->__cpu_power;
+ group = group->next;
+ } while (group != child->groups);
+
+ if (power != sdg->__cpu_power)
+ sdg->reciprocal_cpu_power = reciprocal_value(sdg->__cpu_power);
+}
/**
* update_sg_lb_stats - Update sched_group's statistics for load balancing.
@@ -3712,7 +3734,8 @@
* @balance: Should we balance.
* @sgs: variable to hold the statistics for this group.
*/
-static inline void update_sg_lb_stats(struct sched_group *group, int this_cpu,
+static inline void update_sg_lb_stats(struct sched_domain *sd,
+ struct sched_group *group, int this_cpu,
enum cpu_idle_type idle, int load_idx, int *sd_idle,
int local_group, const struct cpumask *cpus,
int *balance, struct sg_lb_stats *sgs)
@@ -3723,8 +3746,11 @@
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_sched_power(sd);
+ }
/* Tally up the load of all CPUs in the group */
sum_avg_load_per_task = avg_load_per_task = 0;
@@ -3828,7 +3854,7 @@
local_group = cpumask_test_cpu(this_cpu,
sched_group_cpus(group));
memset(&sgs, 0, sizeof(sgs));
- update_sg_lb_stats(group, this_cpu, idle, load_idx, sd_idle,
+ update_sg_lb_stats(sd, group, this_cpu, idle, load_idx, sd_idle,
local_group, cpus, balance, &sgs);
if (local_group && balance && !(*balance))
@@ -3863,7 +3889,6 @@
update_sd_power_savings_stats(group, sds, local_group, &sgs);
group = group->next;
} while (group != sd->groups);
-
}
/**