[PATCH v3 04/12] sched: Allow all archs to set the power_orig

From: Vincent Guittot
Date: Mon Jun 30 2014 - 12:10:05 EST


power_orig is only changed for system with a SMT sched_domain level in order to
reflect the lower capacity of CPUs. Heterogenous system also have to reflect an
original capacity that is different from the default value.

Create a more generic function arch_scale_cpu_power that can be also used by
non SMT platform to set power_orig.

The weak behavior of arch_scale_cpu_power is the previous SMT one in order to
keep backward compatibility in the use of power_orig.

Signed-off-by: Vincent Guittot <vincent.guittot@xxxxxxxxxx>
---
kernel/sched/fair.c | 24 ++++++++++++++++--------
1 file changed, 16 insertions(+), 8 deletions(-)

diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c
index 148b277..f0bba5f 100644
--- a/kernel/sched/fair.c
+++ b/kernel/sched/fair.c
@@ -5614,6 +5614,20 @@ unsigned long __weak arch_scale_smt_capacity(struct sched_domain *sd, int cpu)
return default_scale_smt_capacity(sd, cpu);
}

+unsigned long __weak arch_scale_cpu_capacity(struct sched_domain *sd, int cpu)
+{
+ unsigned long weight = sd->span_weight;
+
+ if ((sd->flags & SD_SHARE_CPUCAPACITY) && weight > 1) {
+ if (sched_feat(ARCH_CAPACITY))
+ return arch_scale_smt_capacity(sd, cpu);
+ else
+ return default_scale_smt_capacity(sd, cpu);
+ }
+
+ return SCHED_CAPACITY_SCALE;
+}
+
static unsigned long scale_rt_capacity(int cpu)
{
struct rq *rq = cpu_rq(cpu);
@@ -5650,18 +5664,12 @@ static unsigned long scale_rt_capacity(int cpu)

static void update_cpu_capacity(struct sched_domain *sd, int cpu)
{
- unsigned long weight = sd->span_weight;
unsigned long capacity = SCHED_CAPACITY_SCALE;
struct sched_group *sdg = sd->groups;

- if ((sd->flags & SD_SHARE_CPUCAPACITY) && weight > 1) {
- if (sched_feat(ARCH_CAPACITY))
- capacity *= arch_scale_smt_capacity(sd, cpu);
- else
- capacity *= default_scale_smt_capacity(sd, cpu);
+ capacity *= arch_scale_cpu_capacity(sd, cpu);

- capacity >>= SCHED_CAPACITY_SHIFT;
- }
+ capacity >>= SCHED_CAPACITY_SHIFT;

sdg->sgc->capacity_orig = capacity;

--
1.9.1

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