arm: wire frequency-invariant accounting support up to the task sched…

…uler

Commit dfbca41 ("sched: Optimize freq invariant accounting")
changed the wiring which now has to be done by associating
arch_scale_freq_capacity with the actual implementation provided
by the architecture.

Define arch_scale_freq_capacity to use the arch_topology "driver"
function topology_get_freq_scale() for the task scheduler's
frequency-invariant accounting instead of the default
arch_scale_freq_capacity() in kernel/sched/sched.h.

Signed-off-by: Dietmar Eggemann <dietmar.eggemann@arm.com>
Acked-by: Vincent Guittot <vincent.guittot@linaro.org>
Acked-by: Russell King <rmk+kernel@armlinux.org.uk>
Tested-by: Juri Lelli <juri.lelli@arm.com>
Reviewed-by: Juri Lelli <juri.lelli@arm.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

arch/arm/include/asm/topology.h

@@ -24,6 +24,11 @@ void init_cpu_topology(void);
 void store_cpu_topology(unsigned int cpuid);
 const struct cpumask *cpu_coregroup_mask(int cpu);
 
+#include <linux/arch_topology.h>
+
+/* Replace task scheduler's default frequency-invariant accounting */
+#define arch_scale_freq_capacity topology_get_freq_scale
+
 #else
 
 static inline void init_cpu_topology(void) { }